JPH0827581B2 - Image forming device - Google Patents

Description

Description: TECHNICAL FIELD [0001] The present invention relates to an image forming apparatus such as an electronic copying apparatus that facilitates adjustment of image forming operations such as image focus adjustment and image tip position adjustment.

[Technical Background of the Invention] Generally, for example, in an electronic copying apparatus, it is necessary to perform focus adjustment for each unit due to variations in focal length of lenses and variations in mounting positions of mirrors and the like.
Further, the leading edge of the image on the photoconductor drum and the leading edge of the paper often do not match due to variations in attachment of various parts, and it is necessary to adjust the leading edge position of the image. Conventionally, such as focus adjustment and image tip position adjustment,
When adjusting the image forming operation electrically, set the adjustment value using a DIP switch, etc., read it by the microcomputer, and change the position of the lens and mirror and the paper feed timing according to the read value. It was done by doing.

[Problems of background art] However, in such an adjusting method, since the DIP switch is generally mounted on a printed circuit board in which a control circuit and the like are incorporated, it is necessary to open the cover of the copying apparatus after each adjustment. Therefore, there is a problem that it is very troublesome and adjustment is difficult while performing the copying operation.

[Object of the Invention] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an image forming apparatus in which adjustment relating to an image forming operation can be performed extremely easily and accurately.

[Summary of the Invention] In order to achieve the above object, the present invention provides a storage unit for storing various initial setting data used when performing image formation, and various storage units stored in the storage unit. By changing the initial setting data, various adjustments related to image forming operations such as the amount of movement of movable parts such as lenses and mirrors, the timing of paper feed, etc. can be performed. The adjustment mode is entered by pressing the key, the contents stored in the storage means are changed, and the adjustment mode is changed from the adjustment mode to the normal mode by simultaneously pressing a plurality of keys of the numeric keypad which are different in combination from the plurality of predetermined keys. It is configured to be restored.

[Embodiment of the Invention] An embodiment of the present invention will be described below with reference to the drawings.

3 and 4 show an electronic copying apparatus as an example of the image forming apparatus according to the present invention. That is, 1
Reference numeral 2 denotes a copying apparatus main body, 2 also serves as a mounting table on which the copying apparatus main body 1 is placed, receives the paper P discharged from the discharge unit of the copying apparatus main body 1 as necessary, and multiplex or double-side the paper P This is a direction-changing and conveying device that guides the image to the copying apparatus main body 1 again in the state as it is or in the state where it is turned upside down so as to form an image. An automatic document feeder 3 is mounted on the upper surface of the copying apparatus main body 1 and automatically supplies the original O.

The copying apparatus main body 1 is constructed as shown in FIG. That is, reference numeral 4 denotes a housing, and an upper surface of the housing 4 is provided with a document table 5 on which an original O fed by the automatic document feeder 3 is placed, and a front end edge portion of the upper surface of FIG. An operation panel 6 described later is provided. In addition, a paper feed cassette is provided on the right side surface of the housing 4.
7,8,9 are installed. The cassette cover 10 of the upper sheet feeding cassette 7 serves as a manual sheet feeding table 11 for manually feeding the sheet P by hand. On the other hand, the photosensitive drum 12 is arranged in the substantially central portion of the housing 4. Around the photosensitive drum 12, a charging device 13 and an exposure optical device 1 are provided.
4. A two-color developing device 15, a transfer device 16, a peeling device 17, a cleaning device 18, and an afterimage erasing device 19, which will be described later, are sequentially arranged. In addition, a paper feed cassette is provided in the lower part of the housing 4.
The paper P supplied from the automatic paper feeder 20 having the papers 7, 8 and 9 mounted thereon, the paper P manually supplied from the manual paper feed tray 11, and the paper P guided from the direction changing / conveying device 2 are photoconductors. A paper conveyance path 23 is formed which leads to an ejection section 22 provided on the left side surface of the housing 4 via an image transfer section 21 between the drum 12 and the transfer device 16. Further, a registration roller 24 is arranged on the upstream side of the image transfer section 21 of the paper conveyance path 23, and a fixing device 25 and a paper discharge roller 26 are arranged on the downstream side.

The operation panel 6 is constructed as shown in FIG. That is, 30 is a copy key for executing a copy operation, 31
Is a preheat key for setting the copier to a preheat state, 32 is an interrupt key for setting an interrupt mode for performing interrupt copying, 33 is a total counter key to be pressed when checking the total number of copies, and 34 is Numeric keypad for setting the number of copies, 35 is a color selection key for selecting the copy color, 36 is a magnification setting key for setting the copy magnification, 37 is a magnification display lamp group for displaying the magnification set by the magnification setting key 36 , 38 are zoom keys that can continuously change the copy magnification within a predetermined range,
Reference numeral 39 is a first display portion for displaying the operating procedure and the state of the copying apparatus in text and also showing the set number of copies and magnification, 40 is a second display portion for displaying an abnormality of the copying apparatus by an illustration, 41 is a copy Manual exposure key for manually setting the density, 42 is an automatic exposure key for automatically setting the copy density,
43 is a mode setting key for setting the copy mode. By pressing this mode setting key 43, the mode display lamp 44
~ 47 lights up sequentially, and the copy mode can be switched. The mode display lamp 44 is a double copy mode display lamp. In this mode, the first copy and the second copy can be performed on the front surface of one sheet. The mode display lamp 45 is a double-sided copy mode display lamp for a single original. In this mode, the first copy and the second copy are 1 each.
It can be done on the front and back of a sheet of paper. The mode display lamp 46 is a two-sided copy mode display lamp for two originals.
In this mode, set two originals on the original table 5 and
It is possible to copy the first document on the front side of one sheet and the second document on the back side thereof. The mode display lamp 47 is a double-sided copy mode display lamp for a book.
The page can be copied on the front side of the first sheet, the second page on the front side of the second sheet, and the third page on the back side of the second sheet. Further, 48 is a main copy mode designation key, and 49 is a main copy mode display lamp. In this mode, the first page of the book can be copied on the front side of the first sheet and the second page can be copied on the front side of the second sheet.

The exposure optical device 14 is constructed as shown in FIGS. 6 and 7. That is, the back lamp is surrounded by the reflector 50 and the exposure lamp 51 that irradiates the original O on the original table 5 with light, and the first reflected light from the original O in a predetermined direction.
A first optical unit 53 which has a mirror 52 and can move along the lower surface of the document table 5, and a half of the speed of the first optical unit 53 in the same direction in synchronization with the first optical unit 53. A second optical unit 57 having a second mirror 55 and a third mirror 56 that moves at a speed and reflects the optical image reflected by the first optical unit 53 to the lens unit 54 side is provided. Further, in the subsequent stage of the lens unit 54, a third optical unit 60 having a fourth mirror 58 and a fifth mirror 59, and an optical image reflected by the third optical unit 60 are reflected to the photosensitive drum 12 side. The sixth mirror 61 is fixed. Reference numeral 62 is a dustproof glass provided between the sixth mirror and the photosensitive drum 12, and 63 is a heat ray absorbing glass provided in front of the exposure lamp 51.

Then, while the exposure lamp 51 is on, the first optical unit 53 moves along the document table 5 at the speed V, and in synchronization with this movement, the second optical unit 57 moves in the same direction at the speed V of 2 V. By moving at a speed of one-half, the original document O placed on the original document table 5 is scanned to form an image on the photosensitive drum 12 which is rotating in advance, and is uniformly charged by the charging device 13. An electrostatic latent image corresponding to the original O is formed on the photosensitive drum 12.

The electrostatic latent image thus formed is developed by facing the developing device 15, and then sent to the image transfer portion 21 facing the transfer device 16, and the developer image on the photosensitive drum 12 is It is transferred to the paper P fed through the registration rollers 24. Then, the paper P on which the image is transferred is peeled from the photoconductor drum 12 by the peeling device 17, and then the conveyance path.
The image is guided to the fixing device 25 through 23, and the image is fixed, and is discharged to the discharge unit 22 via the discharge roller 26. On the other hand, the surface of the photosensitive drum 12 after the developer image is transferred onto the paper P is
By facing the cleaning device 18, residual developer (toner)
After that, the afterimage is erased by the afterimage erasing device 19 to enable the next copying operation.

Further, as will be described later, the lens unit 54, and
The third optical unit 60 having the fourth and fifth mirrors 58 and 59 arranged at an angle of 90 degrees changes the object-image distance and the distance between the lens and the image plane in order to change the copy magnification. The structure is such that it can move as shown by arrows B and C in FIG.

Further, as shown in FIGS. 5 and 7, a first shielding member 65 also serving as a lens cover is provided in a state of covering the upper surfaces of the lens unit 54 and the third optical unit 60, and the second optical unit 57 is also provided. Is provided with a second shielding member 66 so as to partially overlap the first shielding member 65, and a cooling air passage along the document table 5 is provided on the upper surface side of the first and second shielding members 65, 66. The partition means 68 is configured to partition to form 67. The non-attachment end side of the second shield member 66 is guided on the first shield member 65 via the support means 69 composed of a roller or a sliding member, so that no special guide means is required. It has become.

In addition, the first optical unit 57, the lens unit 54,
And the lower surface side of the third optical unit 60 has the dustproof glass.
It is in a state of being covered by a partition plate 70 that holds 62 as a part thereof, and one end of this partition plate 70 is in a state of being connected to the fan casing 72 of the exhaust fan 71, so that the housing 4 is almost vertically arranged. It is in a partitioned state.

Then, as shown by the arrow D in FIG.
By the function of the cooling air conduction path 67 from the right side surface of the housing 4,
The cooling air introduced into the inside of the first shielding member 65 and the second shielding member 65
After being guided by the shielding member 66 so as to surely pass along the lower surface side of the document table 5 to the left side surface portion, it is discharged to the outside. Therefore, the exposure lamp 51 can be sufficiently cooled, overheating of the exposure lamp 51 can be prevented, the life of the exposure lamp 51 can be extended, and adverse effects of heat on other parts can be prevented as much as possible. In addition, heating is prevented over the entire area of the document table 5, and the operator does not feel uneasy. In addition, stray light as indicated by arrow E is shielded by the second shield member 66, and image defects due to stray light entering the lens unit 54 can be reliably prevented.

The first optical unit 53 and the second optical unit 57 are attached and supported as shown in FIG.
The optical unit 53 can move at a speed V, and the second optical unit 57 can move at a speed half the speed V. That is, on the mutually opposing surface sides of the rear frame 75 and the front frame 76 that are arranged side by side, the upper horizontal piece 75
The guide frames 77, 77 are mounted in parallel with a, 76a, and the first optical unit 53 and the second optical unit 53 and the second frames are mounted on the guide frames 77, 77 so that the sliders 78, ... An optical unit 57 is installed.
In this way, the first optical unit 53 and the second optical unit 57 movably provided on the guide frames 77, 77.
Is moved in a predetermined direction at a predetermined speed by the optical unit operating means 79. The optical unit operating means 79 is configured as follows. That is,
1, a drive shaft 80 is laid horizontally corresponding to one end side in the moving direction of the second optical unit 53, 57, and drive pulleys 81, 81 are attached to both ends thereof, that is, outside the frames 75, 76, respectively. ing. Further, a driven pulley 82 is rotatably provided via a support shaft 83 on the outside of the frames 75, 76 corresponding to the other ends in the moving direction of the first and second optical units 53, 57. On the other hand, both ends of the carriage 84 of the first optical unit 53 project to the outside of the frames 75 and 76, and both ends of the carriage 85 of the second optical unit 57 extend vertically along the outside surfaces of the frames 75 and 76. The pair of pulleys 86, 87, which have the folded pulley mounting portions 85a, 85b and play the role of a moving pulley, are mounted. In addition, each pulley
A midway portion of the wire 88 is suspended in a predetermined state on 81, 82, 86, 87. That is, the wire 88 having one end fixed to the fixture 90 via the spring 89 is pulled out to the driven pulley 82 side, wound around the first pulley 86 of the second optical unit 57 and folded back, and then wound around the drive pulley 81 a plurality of times. Then, the driven pulley 82 is folded and folded back to the side. Then, after the wire 88 is wound around the driven pulley 82 and wound around the second pulley 87 of the second optical unit 57 and folded back, the other end is fixed to the fixture 92 via the guide 91. Further, both ends of the carriage 84 of the first optical unit 53 are directly fixed to the wire 88.

On the other hand, the drive shaft 80 is interlocked with the stepping motor 94 via a timing belt 93 so that the drive pulleys 81, 81 around which the wire 88 is wound can be driven in the forward or reverse direction. Has become. Then, the first optical unit 53 directly fixed to the wire 88 has the speed V,
Further, the second optical unit 57, to which the pulleys 86 and 87, which play a role of a moving pulley around which the wire 88 is stretched, is attached, is configured to move at a speed half the speed V. Further, as shown in FIG. 9, the pair of pulleys 86 and 87 attached to both ends of the second optical unit 57 are provided on a line parallel to the moving direction of the second optical unit 57, that is, the wire 88.
It is attached to the support shafts 95 and 96, which are arranged independently in the direction along the tension direction of the wire, and the moment in the direction orthogonal to the tension direction of the wire 88 does not work, and it does not generate vibration for a long time. A stable support state can be maintained over the entire length. Reference numeral 97 is a connecting reinforcing member that connects the free end sides of the support shafts 95 and 96 that rotatably support the pulleys 86 and 87.

Further, as described above, in order to change the copy magnification, the lens unit 54 and the fourth unit arranged at a 90-degree angle,
It is necessary to move the third optical unit 60 including the fifth mirrors 58 and 59 by a predetermined amount, that is, when a lens having a focal length f of 210 mm is used, as shown in the table below.

In addition, the lens unit 54 and the third optical unit 60
Is mounted and supported as shown in FIG. 10, and the lens unit 54 can be moved, and the third optical unit 60 can be moved in a state in which the amount of movement is smaller than that of the lens unit 54. Is obtained. That is, a pair of screw shafts 100 and 101 are rotatably installed in parallel across the moving paths of the units 54 and 60, and slide bushes 103 attached to both ends of the carriage 102 with respect to these screw shafts 100 and 101. By externally fitting the ..., The third optical unit 60 is slidably supported. Further, at one end of the carriage 102, the screw shaft 101
The spiral housing 104 is mounted in a state of being engaged with, and the third optical unit 60 reciprocates with the screw shafts 101, 100 as a guide as the screw shaft 101 rotates forward and backward. The screw shaft 101 is configured so that the driving force of the mirror driving stepping motor 105 is transmitted through a pair of gears 106 and 107. On the other hand, one end of the carriage 108 of the lens unit 54 is held by the screw shaft 100 via slide bushes 120, 120, and the other end of the carriage 108 directly mounts a slider 121 attached to the lower surface thereof on the carriage 102 of the third optical unit 60. As a result, it is slidably supported. Further, a spiral housing 122 is attached to one end of the carriage 108 while being engaged with the screw shaft 100, and reciprocates as the screw shaft 100 rotates forward and backward. The screw shaft 100 is configured such that the driving force of the lens driving stepping motor 123 is transmitted through a pair of gears 124 and 125.

Then, the third optical unit 60 moves in a predetermined direction by a predetermined distance according to the forward / reverse rotation of the mirror driving stepping motor 105, and the lens unit 54 moves in a predetermined direction with the forward / reverse rotation of the lens driving stepping motor 123. It will move a predetermined distance. At this time, by changing the drive pulse cycle of the mirror driving stepping motor 105 and the lens driving stepping motor 123, the movement amount per unit time of the third optical unit 60, which requires less movement amount than the lens unit 54, is set. , Is set smaller than the moving amount of the lens unit 54. Then, since the third optical unit 54 has a larger change in focus and magnification with respect to the same movement amount of the lens unit 60 and the third optical unit 54, the third optical unit 54 is slowly moved so as not to have an adverse effect of inertial force, and high position accuracy is obtained. Is obtained.

The developing device 15 is configured as shown in FIGS. 11 to 17. That is, as shown in FIG. 11, it has a first developing roller 130 and a second developing roller 131.
The second developing rollers 130 and 131 are selectively driven so that, for example, black or red development can be performed.
The developing device 15 is divided into a first developing unit 132 including the first developing roller 130 and a second developing unit 133 including the second developing roller 131, and the first developing unit 132 in the upper stage is rarely used. Red developer Da is used, and the second
The developing unit 133 uses a black developer Db that is frequently used. The developers Da and Db are two-component developers composed of toner and carrier.

First developing unit 132 using the red developer Da
As shown in FIG. 13 and FIG. 14, is a first developing roller 130 and a developer magnetic brush D formed on the surface of the first developing roller 130 and the developer stirring section 135.
a'sliding contact portion with the photosensitive drum 12, that is, the developing position 136
The doctor 137, which is provided on the upstream side of the developer magnetic brush Da 'to regulate the thickness of the developer magnetic brush Da', and the developer magnetic brush Da 'on the surface of the first developing roller 130, which is provided on the downstream side of the developing position 136, are scratched. Scraper 1 leading to the dropped developer container 138
39, and the developer agitator 1 contained in the developer container 138.
40 and 140 are housed in a casing 141. The first developing roller 130 includes a magnetic roll 142,
It has a structure having a sleeve 143 externally fitted thereto. The magnetic roll 142 has five magnetic pole portions 144a to 144e.
And the first, third, and fifth magnetic pole portions 144a, 144c, and 144e are the N pole and the
The second and fourth magnetic pole portions 144b and 144d are S poles, and each magnetic pole portion 1
44a to 144e are arranged at an angle of about 50 ° to 70 °, the third magnetic pole part 144c facing the developing position has a magnetic force of 700 to 1000 gauss, and the other magnetic pole parts 144a, 144b, 144d and 144e have a magnetic force of 300 to 600 gauss. It has a distribution.

Therefore, in the first developing unit 132, the rotary sleeve 143 is rotated clockwise in the drawing for development.
In the so-called against mode, the developer brush Da ′ held on the surface of the photosensitive drum 12 is slidably contacted in the direction opposite to the flow of the image on the photosensitive drum 12, so that the photosensitive drum 12 is rotated.
The electrostatic latent image formed on 12 is developed.
By reducing the diameter of the first developing roller 130, the space from the exposure position to the transfer position is reduced as much as possible, and the copying machine is downsized.

In the present invention, since the diameter of the photosensitive drum 12 is 78 mm, the circumference from the exposure position to the transfer position is about 122 m.
There is only m. To widen the developing position, that is, the distance from the exposure position to the transfer position, the charging device 13 and the cleaning device are used.
18 must be made smaller, but it has its limits. For the above reasons, the diameter of the first developing roller 130 is 40 m.
It has already been confirmed by the present inventors that a developing device of m or less can be installed in space. Further, it has been confirmed that the heights of the first developing unit 132 and the second developing unit 133 are limited, and when the diameter of the photosensitive drum 12 is 78 mm, it must be 120 mm or less. That is, it must be thinned together with the first and second developing units 132 and 133. Therefore, most of the developers in the against mode, which are advantageous in space in the height direction, have a small number of poles, and are inexpensive, are adopted. Especially, the first installed on the top
In the developing unit 132, since the opening of the developing device faces downward, in the with mode in which the developer Da flows from the upper direction to the lower direction, problems such as spilling of the developer Da occur.
Also in this respect, the above-mentioned first developing unit 132 is advantageous in the against mode.

Further, in the first developing unit 132, the developer magnetic brush Da ′ on the rotary sleeve 143 has the developer removing means 1
It is supposed to be removed by 45. As shown in FIG. 13, the developer removing means 145 is of an extremely simple and inexpensive system in which it is removed by simply rotating the rotary sleeve 143 in the opposite direction (counterclockwise direction) to that during development. The rotating sleeve 143 reversely rotates after the copying is completed and the developer Da is conveyed in the opposite direction. Therefore, all the developer Da on the rotating sleeve 143 is transferred to the doctor 1 as shown in FIG.
Stored between 37 and scraper 139.

When the magnetic pole portion has five poles, the more the distance between the first magnetic pole portion (conveyance pole) 144a and the fifth magnetic pole portion (conveyance pole) 144e is, the more efficiently the conveyance or non-conveyance of the developer Da is controlled. Therefore, the number of poles is preferably 5 or less.

In addition, the scraper 139 has a rotating sleeve 1
An elastic thin plate member (not shown) such as Mylar (trade name) is attached in contact with 43 to further enhance the effect of preventing the developer Da from being conveyed backward. Further, the reverse rotation operation of the rotating sleeve 143, that is, the removing operation of the developer magnetic brush Da ′,
It is performed not only after the development operation (after the copying operation) but also after the careless stop of the apparatus. That is, in the event that the device is suddenly stopped due to power off, paper jam, etc., the power system is turned on, paper jam is removed, and the optical system of the exposure optical device 14 returns to the initial state. At the same time, it is reversed again. And, in the state of [copyable], that is, when ready, the rotating sleeve 14
The structure is such that the developer Da does not exist at least near the developing position 136 on 3.

The diameter of the rotating sleeve 143 is about 40 mm or less, and the width is about 230 mm.
In the case of a small size of about mm or less, as a method of controlling the conveyance and non-conveyance of the developer Da, in addition to changing the rotation direction of the rotary sleeve 143, the first magnetic pole part 144a is used. The magnetic roll 142 is placed via a drive source such as a solenoid so as to face the doctor 137 made of a non-magnetic member.
It can also be implemented by rotationally displacing.

On the other hand, the second developing unit 13 using the black developer Db
As shown in FIGS. 14 and 15, 3 includes a developing mechanism section 146 and a developer stirring section 147, a second developing roller 131, and a developer magnetic brush D formed on the surface of the developing roller 131.
Sliding contact portion of b ′ with the photosensitive drum 12, that is, the developing position 148
A doctor 149 that is provided on the upstream side with respect to the thickness of the developer magnetic brush Db ′, guides the developer Db scraped off by the doctor 149 to the developer accommodating portion 150, and the developer accommodating portion. The developer agitator 152 housed in 150 and the developer agitator 152 are housed in a casing 153. And the second
The developing roller 131 includes a magnetic roll 154 and the magnetic roll 15
Rotating sleeve 155 that is fitted onto 4 and rotates counterclockwise in the figure
It consists of and.

In the second developing unit 133, the second developing roller 131 is made larger than the first developing roller 130 in order to enable high speed development, and the rotary sleeve 155 is rotated counterclockwise in the drawing for development. In the so-called with mode, the developer magnetic brush Db 'held on the surface of the photosensitive drum 12 is slidably contacted in a direction following the flow of the image on the photosensitive drum 12, so that a sufficient developing time is secured and the photosensitive drum 12 The electrostatic latent image formed on the surface is developed in a high quality image state.

The magnetic roll 154 has six magnetic pole parts 1 which is one more than the first developing roller 130 so as to be suitable for the with mode.
56a to 156f, and second, fourth and sixth magnetic pole portions 156b, 156d, 156f
Is an N pole, and the first, third, and fifth magnetic pole portions 156a, 156c, 156e are S poles, and each magnetic pole portion 156a to 156f is arranged at an angle of about 50 ° to 60 ° and faces the developing position. The fourth magnetic pole portion 156d is 800 to 1
000 gauss, other magnetic pole parts 156a, 156b, 156c, 156e, 156f are 400
It has a magnetic pole distribution of ~ 600 gauss.

Further, in the second developing unit 133, the developer magnetic brush Db ′ on the rotary sleeve 155 has the developer removing means 1
It is supposed to be removed by 57. The developer removing means 157 is, as shown in FIGS. 14 and 15, a blade 158 made of an elastic member such as urethane rubber, and a blade moving mechanism 159 for horizontally moving the blade 158.
It is configured to prevent the developer Db from being conveyed to the developing position 148 by pressing the blade 158 against the surface of the rotating sleeve 155. The blade moving mechanism 159 has a structure in which a rack 162 provided on a slider 161 integrated with a blade holder 160 is engaged with a pinion 164 driven by a motor 163. And
By rotating the motor 163 in the forward and reverse directions, the slider 161 is moved back and forth to bring the blade 158 into contact with the surface of the photosensitive drum 12 as shown in FIG. 15, or as shown in FIG. It is designed to be separated from 12 surfaces. Further, the pressing position of the blade 158 to the photosensitive drum 12 is from the position of the doctor 149 to the second magnetic pole portion (conveying pole) 1
Exists between 56b. This is because the position of the second magnetic pole portion 156b is most efficient for scraping off the developer brush Db ', but when the distance is widened, the amount of the developer Db accumulated between the blade 158 and the doctor 149 is large. Therefore, the developer Db accumulated during the next copying may be scraped off with the rotation of the photosensitive drum 12 and stain the inside of the machine.
The pressure contact position of 158 is a position where the developer Db is less accumulated and the scraping is efficiently performed, that is, the doctor 149 and the second position.
It is set between the magnetic pole portion 156b. 166 and 167 are position detectors that detect the forward and backward positions of the slider 161, and the motor 163 is stopped by these detection signals.

Further, the blade 158 contacts the photosensitive drum 12 immediately after the rotary sleeve 155 stops as shown in FIG. 15 after the copying operation is completed, and then the rotary sleeve 155 stops for more than half a rotation and then stops. 158 is spaced from the rotating sleeve 155 as shown in FIG. Therefore, at least the developer Db at the developing position on the rotary sleeve 155 is removed. Further, the contact operation of the blade 158, that is, the removing operation of the developer magnetic brush Db ′ is performed not only after the developing operation is completed (after the copying operation) but also in the careless device as in the case of the first developing unit 132 described above. It is also done after the stop. That is, in the event that the device is suddenly stopped due to power off, paper jam, etc., the power system is turned on, paper jam is removed, and the optical system of the exposure optical device 14 returns to the initial state. At the same time, the contact operation of the blade 158 is performed again.
The developer Db does not exist at least in the vicinity of the developing position 148 on the rotary sleeve 155 in the [copyable] state, that is, when ready.

In addition, the first and second developing units 13 configured as described above
2, 133 are selectively operated by designation from a color designation unit (not shown). That is, when the red color is designated, as shown in FIG. 16, the rotary sleeve 1 of the first developing unit 132 is
The magnetic brush Da 'is formed only on 43, and when black is designated, the magnetic brush Db' is formed only on the rotary sleeve 155 of the second developing unit 133 as shown in FIG. .

When the first developing unit 132 side is designated to operate, the first developing roller 13 is operated as shown in FIG.
The rotating sleeve 143 of 0 rotates clockwise,
A developer magnetic brush Da ′ is formed on the surface of 143. Then, the electrostatic latent image previously formed on the photoconductor drum 12 is developed with the red developer Da. When the development of the electrostatic latent image is completed, the developer removing unit 145 operates and the rotating sleeve 143 reversely rotates as described above, and the next developing operation is performed with the developer Da at least at the developing position 136 removed. Prepare for At this time, the developer magnetic brush Db ′ is not formed on the rotary sleeve 155 of the second developing unit 133 either, and either of the developing units 132 and 133 is next.
Even if is specified, problems such as color mixing do not occur.

When the second developing unit 133 side is designated to operate, the rotating sleeve 155 of the second developing roller 131 rotates counterclockwise as shown in FIG.
A developer magnetic brush Db ′ is formed on the surface of 55. Then, in order to cope with high-speed copying, the electrostatic latent image previously formed on the photoconductor drum 12 whose rotation speed is controlled higher than that at the time of development by the first developing unit 132 is developed with the black developer Db. When the development of the electrostatic latent image is completed, the developer removing unit 157 operates as described above, the blade 158 is pressed against the surface of the rotating sleeve 155, and at least the developer Db at the developing position 148 is removed. Prepare for the next development operation. At this time, the first developing unit 13
The developer magnetic brush Da ′ is not formed on the second rotary sleeve 143, so that even if any one of the developing units 132 and 133 is designated next, problems such as color mixing do not occur. The process speed is increased during black copying, and the process speed is decreased during color (red) copying to improve the image quality during color copying.

Then, during black copying, that is, the second developing unit 13
When developing in 3, the peripheral speed of the photosensitive drum 12 is 223 mm / s, 35 sheets / minute, and in the case of color copying to the A4 landscape, that is, when developing in the first developing unit 132, the peripheral speed of the photosensitive drum 12 is 136 mm.
/ s, 25 / min, variable to A4 horizontal speed, first developing roller 130
The diameter is smaller than the 50 mm of the second developing roller 131, which is 38 mm, and by sufficiently securing the developing time, a high quality color image can be obtained. Furthermore, black copying, which is frequently used, enables high-speed copying.

Also, the first and second developing units configured as described above.
As shown in FIG. 18, the developer receiving / conveying unit 13 is exposed to the developer by the front cover 170 as shown in FIG.
2a and 133a are projected, and these developer receiving and conveying parts 132
Cartridge type developer replenishing devices 171 and 172 are detachably mounted in a state of being connected to a and 133a. Then, the detection signals from the developer empty detectors 173 and 174 (see FIG. 5) for detecting the developer amount (toner amount) of the developer accommodating portions 138 and 150 detect the amounts of the developer Da and Db commensurate with the consumption amount. Is appropriately supplied.

The developer replenishing device 172 on the side of the second developing unit 133 is
It is constructed as shown in FIGS. 19 to 22. That is, 175 is a container for storing the developer Da.
A transfer screw 176 that transfers the developer Db in the axial direction by being rotationally driven is accommodated in the bottom of the 75. A fitting protrusion 175a that can be inserted into and removed from a holder 177 that is connected to the developer receiving and conveying unit 133a is provided at a lower portion of one end of the container 175 located in the developer conveying direction of the conveying screw 176. Has been formed. A developer discharge port 178 for discharging the developer Db transferred by the transfer screw 176 is formed on the lower surface side of the fitting protrusion 175a.
The holder 177 is rotatably attached to the upper surface side of the developer receiving / conveying section 133a, and the holder 177 has a developer transfer shaft (toner auger) 182 of the developer receiving / conveying section 133a on its bottom surface. Correspondingly, the supply port 179 is formed. At one end of the transfer screw 176,
The holder 177 has a connecting portion 176a protruding from the end surface of the holder 177 and connected to the drive coupling 181 of the drive device 180. A lid 183 is slidably provided on the lower surface of the fitting protrusion 175a to open and close the developer discharge port 178. On the other hand, on the holder 177 side, a recess 184 that engages with the engagement protrusion 183a formed on the lid 183 is formed, and as shown in FIG. As shown in (a) and (b), the lid 183 slides to open and close the developer discharge port 178. Further, as shown in FIGS. 18 and 19, the drive device 180 includes a gear 186 integral with the coupling 181, a worm gear 187 meshing with the gear 186, and the worm gear.
It has a motor 188 for driving 187 and is attached to a movable base 190 which is slidable in the direction of arrow F in FIG. Then, the motor 188 is driven for a predetermined time by the detection signal from the developer empty detector 174, and the transfer screw 176 rotates. As a result, the developer Db in the container 175 is sent to the developer discharge port 178 side, and is sent to the replenished port 179 of the developer receiving and conveying section 133a. Next, the supply receiving port 179 of the developer receiving and conveying section 133a.
The developer Db sent to is conveyed upward in the developer accommodating portion 150 as the developer transfer shaft 182 rotates.

On the other hand, at the bottom of the developer guide 200 which surrounds the developer transfer shaft 182, the developer discharge ports 201a to 201h are provided at intervals La to Lg as shown in FIG. The developer agitating member 152 provided in the developer accommodating portion 150 is distributed over substantially the entire axial direction. The intervals La to Lg between the developer discharge ports 201a to 201h are gradually narrowed in the developer transfer direction, and the opening areas of the developer discharge ports 201a to 201h are large on the developer transfer direction side. Therefore, the developer Db is evenly distributed.

When the cartridge type developer replenishing device 172 is to be removed, such as when the developer Db has run out, first the drive device 180 is displaced rightward in the state of FIG. 19 to move the transfer screw 176. The engagement operation between the coupling portion 176a and the coupling 181 is released. Next, after the entire developer replenishing device 172 is rotationally displaced to the front side with the holder 177 as the center, the fitting protrusion 175a is pulled out from the holder 177 by pulling it toward the front side. Further, when a new developer replenishing device 172 is attached, it suffices to perform the reverse procedure described above.

On the other hand, the developer replenishing device 1 on the side of the first developing unit 132
As shown in FIG. 19 and FIG. 20, 71 has substantially the same structure as the developer replenishing device 172 on the second developing unit 133 side. That is, 210 is a container that stores the developer Da, and a transfer screw 211 that transfers the developer Da in the axial direction by being rotationally driven is stored at the bottom of the container 210. Transfer screw 2 for the above container 210
A fitting protrusion 210a that can be inserted into and removed from a holder 212 that is connected to the developer receiving and conveying unit 133a is formed in the lower part of one side end located in the developer transfer direction of 11. A developer discharge port 213 for discharging the developer Da transferred by the transfer screw 211 is formed on the lower surface side of the fitting protrusion 210a. The holder 212 includes a developer receiving / conveying unit 133.
It is in a state in which it is rotatably attached to the upper surface side of a, and a supply port 214 is formed correspondingly between the developer stirring bodies 140, 140 composed of a spiral shaft on the bottom surface thereof. ing. At one end of the transfer screw 211, there is provided a connecting portion 211a which projects from the end surface of the holder 212 and is connected to the drive coupling 216 of the drive device 215. A lid 217 is slidably provided on the lower surface side of the fitting protrusion 210a to open and close the developer discharge port 213. On the other hand, on the holder 212 side, a recess 218 that engages with the engaging protrusion 217a formed on the lid 217 is formed, and as described above with the inserting / removing operation of the fitting protrusion 210a with respect to the holder 212. Similarly, a lid body 217 slides to open and close the developer discharge port 213. Further, as shown in FIGS. 18 and 19, the drive unit 215 includes a gear 219 integral with the coupling 216, a worm gear 220 meshing with the gear 219, and a motor for driving the worm gear 220. It has 221 and is attached to a movable base 222 which is slidable in the direction of arrow G in FIG. Incidentally, 223 shown in FIG. 19 is a support member for supporting the side end surface of the container 210. Accordingly, the motor 221 is driven by the detection signal from the developer empty detector 173 described above.
Is driven for a predetermined time, and the transfer screw 211 rotates. As a result, the developer Da in the container 210 is sent to the developer discharge port 213 side and is sent to the supply target port 214 of the developer receiving and conveying section 132a. Next, the supply receiving port of the developer receiving and conveying section 132a
The developer Da sent to 214 is uniformly distributed to the developer accommodating portion 138 by the developer agitating members 140, 140 each having a spiral shaft.

Further, when the cartridge type developer replenishing device 171 is to be removed, such as when the developer Da is exhausted, first, the driving device 215 is displaced rightward in the state of FIG. 19 to move the transfer screw 211. The engagement operation between the coupling portion 211a and the coupling 216 is released. Next, after the entire developer replenishing device 171 is rotationally displaced to the front side with the holder 212 as the center, the fitting protrusion 210a is pulled out from the holder 212 by pulling it toward the front side. Further, when a new developer replenishing device 171 is attached, the reverse procedure described above may be performed.

Further, as shown in FIG. 23 and FIG. 24, a stirring blade 225 is rotatably stored in a container 175 containing the developer Db. A plurality of claws 227 that mesh with the sprocket 226 attached to the transfer screw 176 that transfers the agent Db to the developer discharge port 178 side,
... is projected. Then, the stirring blade 225 is rotated in accordance with the rotation of the transfer screw 176, and the developer Db in the container 175 is prevented from being clumped or biased to reliably supply the developer Db without leaving the developer Db. There is.

On the other hand, the container 210 containing the developer Da is also in a state in which the stirring blades are also stored, and the container 210 is stored in the same manner.
The developer Da in 210 is agitated.

Reference numeral 228 shown in FIG. 18 is a collection box for collecting the developer scraped by the cleaning device 18, and the front cover
It can be easily removed by opening 170. Reference numeral 229 is a magnet catch for holding the front cover 170 by suction.

Next, the structure of the automatic paper feeder 20 will be described with reference to FIGS. 25 to 30. As shown in FIG. 25, the paper P, ...
The paper feed cassettes 7, 8 and 9 accommodating the above are mounted on the upper surface side of the base 240 so as to be freely inserted and removed via guides (not shown). As shown in FIG. 26, these paper feed cassettes 7, 8 and 9 respectively include guides 241, 242a and 242b that regulate the rear end position and both side ends of the paper P, and a paper support plate 243 that supports the paper ejection end side. It has a configuration having. Paper support plate 2 above
43 is in a state in which it is swingably supported by engaging the opposite sheet take-out end side with a groove formed in the bottom surface of the cassette body 244. In addition, this paper support plate 243,
Through holes 245, 245 are formed, and the cassette body 2
There is an opening 246 at the position corresponding to the paper support plate 243 at the bottom of the 44.
Are formed. Further, as shown in FIG. 27, the cassette cover 10 of the uppermost paper feed cassette 7 is provided with a manual paper feed tray 11 as shown in FIG.
And a pair of guide members 247, 24 for guiding the both side end portions of the paper P to be manually fed on the upper surface thereof.
7 are provided. These guide members 247, 247 are attached to the cassette cover 10 as shown in FIG. 28 to FIG. 30, and when one of the guide members 247 is moved, the other guide member 247 moves together. Has become.

FIG. 28 shows a state in which the cassette cover 10 of the paper feed cassette 7 is viewed from the back side, and a pair of racks 249 and 249 around a pinion 248 rotatably arranged at the center in the width direction of the cassette cover 10 are provided. They are arranged symmetrically, one end of each of which meshes with the pinion 248, and the other end of which is fixed to the corresponding guide members 247, 247 via pins 250, 251. Therefore, one guide member 24
When 7 is moved in the width direction H, the other guide member 247
Interlock with this, and slide so that they approach each other or move away from each other. That is, the pinion 248 and the rack 249 constitute an interlocking unit that interlocks both guide members 247. As shown in FIG. 29, the pins 250 and 251 are inserted into the corresponding elongated guide holes 252 with a space, so that the rack 249 is guided so as to move in the width direction H. Further, guide pins 256 are further projectingly provided on the cassette cover 10 on both sides of the pinion 248 so that the rack member 249 is guided and held by the back surface of the corresponding rack 248 so as not to come out of mesh with the pinion 248. are doing. Reference numeral 257 is a guide reinforcing plate attached to the back surface of the cassette cover 10 by an appropriate means, and is provided in the width direction along the traveling path of the rack 249 which is the interlocking means. The guide reinforcing plate 257 is also formed with a long hole so as to match the long hole 252 of the cassette cover 10. Further, a pivot shaft portion 258 that rotatably supports the pinion 248 is projectingly provided on the back surface of the cassette cover 10 as shown in FIG. 30, and a rectangular plate is provided at the upper end portion of the pivot shaft 258. A braking member 259 composed of a spring is attached and fixed by a screw 260. The pair of left and right cut-and-raised tongues 259a, 259a of the braking member 259 are bent and elastically frictionally engaged with the outer peripheral edge of the pinion 248, and both ends 259b, 259b of the braking member 259 are at right angles. The guide pins 256, 256 are engaged with the notches (not shown) formed therein by being bent. Accordingly, the tongue pieces 259a, 259a of the braking member 259 slightly apply a braking action to the pinion 248 due to the rotational movement thereof, so that blind movement such as excessive rotation is prevented. For this reason,
Since the overall movement of the interlocking means is also subjected to a light braking action, it is possible to prevent the blind movement due to the inertia of each member moving during the movement operation of the guide members 247, 247 and the displacement due to vibration.

Further, the sheet supporting plates 243 of the sheet feeding cassettes 7, 8 and 9 are selectively pushed up by the rotating operation of the pushing up lever 264 of the supporting plate pushing up mechanism 263 provided in each cassette mounting portion, and the uppermost end The paper P is pressed against the take-out roller (paper feed roller) 265 with an appropriate pressing force. The support plate lifting mechanism 263 is configured as shown in FIG. That is, 266 is a shaft which is rotatably supported by a bearing (not shown), and the push-up lever 264 and the operating lever 267 are attached to the shaft 266 with their phases shifted by about 180 degrees. . Further, a spring 268 is connected to the actuating lever 267, and the lower surface of the free end portion thereof is in a state of being urged so as to always contact the peripheral surface of the eccentric cam 269. The eccentric cam 269 is a gear 270, 271, 272 that sequentially meshes.
The driving force of the motor 274 is transmitted via the gear mechanism 273 consisting of. Then, as the maximum eccentric portion of the eccentric cam 269 faces the actuating lever 267 as the motor 274 rotates, the actuating lever 267 is pushed up against the biasing force of the spring 268 (indicated by the solid line in FIG. 31). As shown in FIG. 31), the actuating lever 267 is pulled by the force of the spring 268 (the state shown by the chain double-dashed line in FIG. 31) as the minimum eccentric portions face each other. Therefore, the push-up lever 26, which has an integral relationship with the operating lever 267 and the shaft 266,
4 also rotates and is displaced to the state shown by the solid line or the chain double-dashed line in FIG. 31 with this movement.
The sheets P, ... Collected on the sheet 243 are separated from or come into contact with the take-out roller 265.

Further, as shown in FIG. 25, rollers 289 and 290 which are in rolling contact with each other are provided in the sheet take-out direction of the take-out roller 265 as separating means 288 for separating the stacked second and subsequent sheets P and preventing the take-out. Has been. These rollers 289,2
90 is configured as shown in FIG. I.e. 29
Reference numeral 1 denotes a motor, and the motor 291 is in a state of meshing with the gears 293 and 294 via the gear 292. The gear 293 is configured to interlock with the roller 289 via a shaft 295, and the gear 294 is configured to interlock with the roller 290 via a shaft 297 having a spring clutch 296 in the middle. Further, the spring clutch 296 is formed by the roller 28
It is set to slide when the contact force of 9,290 exceeds Ta. If the frictional force between the rollers 289 and 290 is Tb, it is set such that Ta> Tb.
It is designed to rotate according to 90. If the frictional force between the paper P and the paper P is Tf and the frictional force between the roller 265 and the paper P is Tr, the roller 265 is generally formed of a material having a high friction coefficient, such as Tr> Tf. Is.
Then, Ta is set so that Tr>Ta> Tf.
Then, when the sheet is on standby, the sheet P is separated from the take-out roller 265 as shown in FIG. And
At the time of paper feeding, as shown in FIG. 33 (b), after the sheet P is brought into rolling contact with the take-out roller 265 by the pushing-up operation of the push-up lever 264, the uppermost sheet P is rotated as the take-out roller 265 rotates.
Is taken out and is fed between the rollers 289 and 290 which form the separating means 288. At this time, the second and subsequent sheets of paper P adsorbed to and taken out from the uppermost sheet P are separated by the reverse rotation operation of the roller 290 as shown in FIG. 33 (c), and only the uppermost sheet P is separated. Will be taken out. This is because when the paper P enters between the rollers 289 and 290, the roller 289 returns the paper P in the arrow J direction by Tr> Tf, and the roller 290 and the paper P in the opposite direction by Tr>Ta> Tf.
When one sheet is taken out, the push-up lever 264 is lowered as shown in FIG. 33 (d), and it waits again in the state shown in FIG. 33 (a).

Further, as shown in FIG. 34, a control unit (not shown) is connected to the positions corresponding to the bottom side of the paper feeding cassettes 7, 8 and 9 and the position corresponding to the paper transport path immediately before the separating unit 288. Reflective optical sensor 300,30 as a paper detector
1 is provided. Then, the paper non-detection means 302 for determining "paper non-existence" is configured by the sum of the "paper non-existence" detection signals of both the sensors 300 and 301. Then, as shown in FIG. 34 (a), when the paper P is placed on the paper support plate 243, this can be detected when the paper support plate 243 is lowered. , Fig. 34 (b)
As shown in, when the last one separated by the roller 290 is sandwiched by the rollers 289, 290,
The sensor 300 provided at the position corresponding to the bottom side of the paper feed cassette 7 (8, 9) cannot detect this, but the sensor 301 provided at the position corresponding to the paper transport path immediately before the separating means 288. You can detect this with. Therefore, it is possible to prevent the determination of "no paper" despite the presence of the paper P. A reflection type optical sensor is used as the paper detector.
By using 300 and 301, the paper P can be detected in a non-contact state, and moreover, it is less affected by external light as compared with the case where a transmission type optical sensor is used, and there are advantages such as easy mounting.

Further, as shown in FIG. 25, the sheet P that has passed through the separating means 288 is abutted against the contact portion between the rollers 24a and 24b of the registration roller 24 that is stopped, and the inclination (skew) of the tip portion thereof.
After being corrected, it is sent to the image transfer portion 21 in synchronization with the image forming operation on the photosensitive drum 12. Further, a transfer roller 305 including rollers 305 and 306 is arranged between the uppermost separating means 288 and the registration roller 24. The take-out rollers 265, ..., the roller 305b of the transfer roller 305, and the roller 2 of the registration roller 24.
.. are configured to be driven via the power transmission system 306 shown in FIG. That is, 307 is a stepping motor, and the drive gear 308 attached to the drive shaft of the motor 307 is in a state of meshing with the gear 310 via the intermediate gear 309. The gear 310 is attached to the shaft of one roller 24a of the registration roller 24 via a one-way clutch 311. Further, a sprocket 312 is integrally attached to the intermediate gear 309, and is configured to interlock with a sprocket 315 that is integral with a driven gear 314 via a chain 313. The sprocket 315 is attached to the shaft of the roller 305b via the one-way clutch 319, and the gear 314 is attached to the shaft of the roller 305b. The driven gear 314 is in a state of meshing with the gear 318 attached to the shaft of the take-out roller 265 via the intermediate gears 316 and 317 in order.

Then, when the motor 307 rotates in the forward direction (the direction indicated by the solid line arrow), the one-way clutch 311 turns off and the one-way clutch 315.
Is turned on and the take-out roller 265 and the roller 305b are turned on.
Is driven, and power is not transmitted to the roller 24a and the roller 24a is stopped. When the motor 307 rotates in the opposite direction (the direction of the arrow indicated by the broken line), the one-way clutch 311 is turned on and the one-way clutch 315 is turned off, so that only the roller 24a is driven and the rollers 305b and 265 are connected to the one-way clutch 319. Power is not transmitted due to work and is in a stopped state. In this manner, the take-out roller 265 and one roller 24a of the registration rollers 24 are selectively rotated by the forward and reverse rotations of the pulse motor 307.

Further, in the uppermost sheet feeding cassette mounting portion, the sheets P, ... Collectively set on the manual feeding tray 11 are sequentially taken out one by one, and fed to the separating means side via the take-out roller 265. A roller 321 is provided. The manual feed roller 321 and the take-out roller 265 are configured so that they can be brought into and out of contact with the paper conveying path by a roller contacting / separating means 322 shown in FIGS. 25 and 36, and at least during manual paper feeding. 265
Is separated from the paper transport path. That is, the support shaft 265a of the take-out roller 265 is attached to and supported by the free ends of the arms 323, 323 rotatable about the support shaft 289a of the roller 289 of the separating means 288 as a fulcrum. Also, manual roller 321
Is attached to and supported by the free ends of the arms 324, 324 which are rotatable around the support shaft 265a of the take-out roller 265 as a branch. On the free ends of the arms 324, 324, hooking protrusions 324a, 324a are integrally provided in a state orthogonal to each other,
These latching protrusions 324a, 324a are attached to a lever 3 attached to a rotating member 326 that is rotatably supported by a supporting shaft 325 as a fulcrum.
It is extended above the free ends of 27,327. The rotating member 326 is constantly urged in the counterclockwise direction by the spring 328 in the state shown in FIG. 25, and the arms 324, 324 holding the support shaft 321a of the manual feed roller 321.
The latching protrusions 324a, 324a are in a lifted state. Further, a plunger 329a of a plunger type solenoid 329 is connected to the rotating member 326 via a connecting member 330, so that the rotating member 326 can be rotated against the biasing force of the spring 328. ing. Note that in FIG. 25, reference numeral 331 is a manual paper feed switch arranged on the front side of the manual feed roller 321. Further, as shown in FIG. 36, a sprocket 332 is attached to a support shaft 265a of the take-out roller 265, and a sprocket 333 is attached to a support shaft 321a of the manual feed roller 321. These are interlocked with each other via a chain 334. It is supposed to do.

Then, when the paper P is placed on the manual paper feed table 11, the manual paper feed switch 331 is turned on, and the solenoid 329 is turned on when the copy key 30 is turned on. Then, the rotating member 326 is rotationally displaced against the urging force of the spring 328, the manual feed roller 321 is lowered, and the take-out roller 265, which is a perfect circular roller, is moved away from the sheet conveyance path in conjunction with this movement. Displaces upward. Then, the paper P is the separating means 288.
Then, the solenoid 329 is turned off, the manual feed roller 321 is raised, and the take-out roller 265 is lowered accordingly. At this time, the push-up lever 264 that pushes up the paper support plate 243 of the paper feed cassette 7 is lowered, and the paper P is separated from the take-out roller 265.

Next, the structure of the fixing device 25 will be described with reference to FIG. This fixing device 25 is roughly classified into an upper roller unit 33.
6 and the lower roller unit 337. The upper roller unit 336 accommodates a heat source (not shown) inside and a heat roller 338 having a Teflon coat on its outer surface is mounted on a bracket 340 pivotally supported by a support shaft 339. It is installed. Also,
The lower roller unit 337 has a structure in which a pressure roller 341 made of a rubber roller is attached to a bracket 343 which is constantly urged upward by a compression spring 342. The bracket 343 has long holes 345, 345 through which the guide shafts 344, 344 are inserted.
It is possible to move up and down within the range of the long holes 345, 345. A movable frame 346 is provided near the free end side of the bracket 340 of the upper roller unit 336. This movable frame 346
Is a part of a frame of an upper unit which is rotatably provided so as to be separated from the lower unit with the sheet conveying path 23 of the housing 4 as a boundary. As shown in FIG. 37 (a), when the upper unit is superposed on the lower unit, the movable frame 346 is in contact with the upper surface of the bracket 340 on the free end side, and the heat roller 338 is compressed. The pressure roller 341 resists the urging force of the spring 342.
Is pressed down to make a contact pressure so that a predetermined contact pressure can be obtained. In addition, when the upper unit is separated from the lower unit to open the paper transport path 23 as needed for paper jam, inspection, etc., the movable frame is
346 is largely separated from the upper surface of the bracket 340 on the free end side, and the bracket 340 is supported by the support shaft 339 as shown in FIG. 37 (a).
With the rotation fulcrum as a fulcrum, it can be rotated and displaced up to about 95 degrees. Note that such a configuration facilitates replacement of the heat roller 338 and the pressure roller 341.

Next, the sheet P discharged from the sheet discharge unit 22 of the copying apparatus main body 1 configured as described above is received as necessary,
The direction-changing and conveying device 2 is fed again to the image forming portion of the copying apparatus main body 1 in the state as it is or in the state in which the inside and outside are reversed.
The configuration will be described with reference to FIGS. 38 to 42. As shown in FIG. 38, the direction-changing and conveying device 2 is composed of a unit independent of the copying apparatus main body 1, and also serves as a mounting table on which the copying apparatus main body 1 is detachably mounted. The direction-changing and conveying device 2 is provided in the vicinity of the discharge portion 22 of the copying apparatus main body 1 and is provided with a guide means 350 for introducing the discharged paper P as necessary, and the paper P guided by the guide means 350. A carry-in path 351 for carrying in the paper and a temporary stacking unit 352 for temporarily stacking the paper P carried in through the carry-in path 351.
Then, taking out means 353 for taking out the sheets P accumulated in the temporary accumulating section 352 one by one, and for forming a multiple image on the sheets P taken out by the taking out means 353, again without changing the leading end direction thereof, In order to form a double-sided image on the first conveyance unit 355 that leads to the sheet introduction unit 354 of the copying apparatus main body 1 and a state in which it is branched from the first conveyance unit 355, and the paper P that has been taken out by the take-out unit 353, A second conveying unit 356 which changes the conveying direction so that its rear end is the leading end and guides it again to the sheet introducing unit 354 of the copying apparatus main body 1, and a branching unit between the second conveying unit 356 and the first conveying unit 355. A sorting means 357 which is provided and selectively sorts the paper P taken out by the taking-out means 353.
And driving means 358, 359 for switching the guide means 350, the sorting means 357, etc. by a switching signal or the like by operating the mode setting key 43.

The guide means 350 includes a gate 362 rotatably provided by a support shaft 361. The gate 362 linearly conveys to the paper discharge tray 364 via the paper discharge unit 22 and the paper discharge roller 363 of the copying apparatus main body 1. The sheet P is provided at a branch point between the path 365 and the carry-in path 366 leading to the temporary stacking section 352, and is driven by the driving means 358 to selectively guide the paper P. That is, the gate 362 is constantly urged in the predetermined direction by the spring 367, and normally, the carry-in path 366 is in the “closed” state and the linear transfer path 365 is in the “open” state. A solenoid 369 is connected to the gate 362 via a connecting member 378, and if necessary, the carry-in passage 366.
Is opened and the linear conveying path 365 is closed, the gate 362 can be rotationally displaced against the biasing force of the spring 367. A first transport roller 370, a second transport roller 371, and a third transport roller 372 are arranged in the carry-in path 366, and the paper P is forcibly fed to the temporary stacking unit 352. It should be noted that, as will be described later, the third conveying roller 372 is configured so that the receiving / carrying-out position of the paper P is movable with respect to the feeding direction of the paper P, and its tip is the end in the take-out direction of the temporary stacking unit 352 regardless of the size of the paper P. It has a structure that can correspond to the take-out means 353 provided corresponding to the side.

The temporary stacking unit 352 is formed by the upper surface of the guide plate 373, and the actuator 374a of the paper detecting unit 374 faces the center of the stacking unit 352.

The take-out means 353 includes a take-out roller 377 held at a free end of an arm 376 pivotally supported by a support shaft 375,
The take-out roller 377 is arranged so as not to interfere with the stacking of the paper P by being displaced upward when the paper P is stacked on the temporary stacking unit 352. That is, on the pivotal end side of the arm 376, there is formed a protrusion 376a that comes into contact with a lever 378 that rotates using a solenoid 378 as a drive source.
When the 378 is turned on, the protrusion 376a is removed and the roller 377
As shown by the solid line in FIG. 38, it is displaced upward, and by the OFF operation, the take-out roller 377 is lowered downward by its own weight as shown by the chain double-dashed line in FIG.
It is designed to be transferred to. Further, the rollers 380a and 380b are arranged in the sheet take-out direction of the take-out means 353 configured as described above.
Conveying roller 380 consisting of
The paper P taken out from 52 is fed into the sorting means 357.

Next, the configuration of the direction changing portion of the paper P taken out from the temporary stacking unit 352 and sent through the transport roller 380 will be described with reference to FIG.
It will be described with reference to the drawings. That is, the transport roller 380
A first transport path 382 for transporting the paper P, a second transport path 384 provided with the transport rollers 383 in communication with the first transport path 382, and from the end of the first transport path 382. A third conveyance path 386 which is branched and has a conveyance roller 385;
The fourth conveyance path 387 is branched from the base end of the second conveyance path 384 so as to join the conveyance path 386.
Further, the paper P, which is provided at the branch point between the first transport path 382 and the third transport path 386 and is transported through the first transport path 382 by the transport rollers 380, is transferred to the second transport path 384 or the third transport path 386. First guide means 388 that selectively guides the second conveying path 384
And a fourth conveyance path 387 and a conveyance roller 383.
Therefore, a second guide means 389 for guiding the paper P, which has been fed back through the second transport path 384, to the fourth transport path 387 side is provided, and constitutes the sorting means 357. Further, in the second conveyance path 384, the conveyance roller 383 detects that the rear end of the paper P guided from the first conveyance path 382 to the second conveyance path 384 reaches a predetermined position, and the conveyance roller 383 conveys the paper P. A paper detection unit 390 is provided to control the paper to be conveyed in the reverse direction. By switching the first and second guide means 388 and 389, the sheet P conveyed through the first conveying path 382 can be conveyed without changing the leading end in the carrying direction, or the trailing end in the carrying direction is on the leading end side. As described above, the conveying direction is changed, the sheet is conveyed, and the sheet can be fed again to the sheet introducing section 354 of the copying apparatus main body 1. Also, the first and second guide means 388, 38 described above.
Reference numeral 9 denotes a guide member that is pivotally supported via a support shaft 391 and that is connected to a plunger 392a of a plunger type solenoid 392 via connecting members 393 and 393, respectively. It is designed to be rotationally displaced as indicated by a solid line or a two-dot chain line.

Here, for example, the operation at the time of double-sided copying of one original will be described.

(A) First, the mode setting key 43 on the operation panel 6 is operated to set the "one-sided document double-sided copy mode", and the number of copies, exposure amount (copy density), copy magnification, etc. are set by another operation. After that, the copy key 30 is pressed.

(B) The solenoid 369 of the guide means 350 is pulled, and the copied sheet P is guided to the direction changing conveyance device 2.

(C) The single-sided copied sheets P are stacked in the temporary stacking unit 352.

(D) The solenoid 396 of the guide means 350 returns.

(E) Replace the original and press the copy key 30 again.

(F) The solenoid 378 of the take-out means 353 provided in the temporary stacking unit 352 is pulled, and the take-out roller 377 descends.

(G) Take-out roller 377, conveyance roller 38 also serving as separating means
0, and the transport roller (switchback roller pair) 383 rotates.

(H) The take-out roller solenoid 378 returns at the time when the leading edge of the paper P reaches the conveyance roller 380 sufficiently, and the take-out roller 377
Rises.

(I) The conveyance roller 380 stops at the time when the leading edge of the paper P reaches the conveyance roller 383 sufficiently. However, the transport roller 380
Has a one-way clutch and is rotated by the paper P until the rear end of the paper P pulled by the transport roller 383 is separated.

(J) When the trailing edge of the paper P has passed the paper detecting means 390, the carrying roller 383 reversely rotates, the solenoid 392 of the distributing means 357 is pulled, and the carrying roller (feed roller pair) 385 rotates.

(K) When the leading edge of the paper P reaches the registration roller 24 located in front of the image transfer portion 21 of the copying apparatus main body 1, the conveyance roller
383 and 385 stop, and the paper P is registered.

(L) When the sheet P is sent to the image transfer section 21 and its rear end is sufficiently separated from the sorting means 357, the solenoid 39 of the sorting means 357
2 returns. However, the transport roller 385 has a one-way clutch and is rotated by the sheet P pulled by the registration roller 24.

(M) With the sorting means 357 still returned, the temporary stacking unit 3
The above (f)-
The operation of (l) will be repeated.

 Next, the operation at the time of double copying will be described.

(A) First, the "double copy mode" is set by operating the mode setting key 43 on the operation panel 6, and the number of copies, exposure amount (copy density), copy magnification, etc. are set by another operation, Press the copy key 30.

(B) The solenoid 369 of the guide means 350 is pulled, and the copied sheet P is guided to the direction changing conveyance device 2.

(C) The single-sided copied sheets P are stacked in the temporary stacking unit 352.

(D) The solenoid 396 of the guide means 350 returns.

(E) Replace the original and press the copy key 30 again.

(F) The solenoid 378 of the take-out means 353 provided in the temporary stacking unit 352 is pulled, and the take-out roller 377 descends.

(G) The solenoid 392 of the distributing means 357 is pulled, and the take-out roller 377, the conveying roller 380 also serving as the separating means, and the conveying roller (feeding roller pair) 385 rotate.

(H) The take-out roller solenoid 378 returns at the time when the leading edge of the paper P reaches the conveyance roller 380 sufficiently, and the take-out roller 377
Rises.

(I) The conveyance roller 380 stops at the time when the leading edge of the paper P reaches the conveyance roller 385 sufficiently. However, the transport roller 380
Has a one-way clutch, and is rotated by the paper P until the rear end of the paper P pulled by the transport roller 385 is separated.

(J) When the leading edge of the paper P reaches the registration roller 24 located in front of the image transfer section 21 of the copying apparatus main body 1, the conveyance roller
After 385 is stopped and the paper P is registered, the paper P is sent to the image transfer unit 21.

(K) With the guide means 350 still returned, the above-mentioned operations (f) to (j) are repeated until there is no one-side copied sheet P in the temporary stacking section 352.

Further, the sheet P discharged from the sheet discharge section 22 of the copying apparatus main body 1 as described above is received as needed, and the image transfer section as an image forming section of the copying apparatus main body 1 is again held in the state as it is or in the state of being turned upside down. In the direction-changing and conveying device 2 configured to form a multiplex or double-sided image on the paper P by guiding the paper to the paper 21, the passage portion of the paper P is demarcated as shown by the two-dot chain line state in FIG. On one side (lower side)
The member located at the outside (lower side) to open the paper passage.
It has a freely displaceable configuration. That is, the carry-in route
Lower guide plate 40 of guide plates 400a, 400b forming part of 366
0a, the lower roller 371a of the conveying roller 371, the guide plate 373 forming the temporary stacking unit 352, the lower guide plate 401 forming the first and second conveying paths 382, 383, the lower roller 380a of the conveying roller 380, and the conveying roller 383. The lower roller 383a is attached to a supporting frame 402 that is provided so as to be rotatable around one side of the sheet P in the conveying direction as a fulcrum, and along with the displacement operation of the supporting frame 402, the lower rollers 383a are simultaneously swept outward to open the sheet passage. It has a structure that can be displaced. Further, on the free end side of the support frame 402, holding means 403, 403 for holding the support frame 402 in a predetermined state.
By operating these holding means 403, 403, the paper conveying section can be opened, and paper jams and the like can be easily dealt with.

Further, as shown in FIG. 40 to FIG. 42, the carrying-in means for receiving the sequentially conveyed sheets P and feeding them in order to accumulate them in the temporary accumulating section 352 is movable in the conveying direction of the sheets P. . That is, the carry-in means has the driving roller 372a as the first carrying roller and the driven roller 372b as the second carrying roller.
It consists of two. The drive roller 372a has a support shaft 407 horizontally movably supported by holding bearings (bushings) 406, 406 by slits 405, 405 serving as guide portions, and the driven roller 372b is connected to the drive roller 372a. It is provided so as to be constantly in rolling contact with the drive roller 372a so as to sandwich and convey the paper P between them, and is configured to be movable integrally with the drive roller 372a. The slits 405, 405 serving as the guide portions are respectively formed in the pair of side frames 408, 408 which face each other with the sheet conveyance path sandwiched therebetween. The bearings 406 and 406 held by the slits 405 and 405 are fixed to predetermined positions according to the size of the paper P by positioning means 409 and 409 provided outside the frames 408 and 408. Further, the positioning means 409, 409 is provided in a state along the moving path of the bearings 406, 406 as shown in FIG. 41 and FIG. 42, and also has a plurality of recessed portions 41 which can be fitted with a part of the outer circumference of the bearing 406.
The lever 411 is provided as a positioning member having 0,410. The lever 411 has one end rotatably attached to the frame 408 via the shaft 412, and has a biasing member that constantly biases the recessed portion 410 on the free end side so that the recessed portion 410 fits into the bearing 406. The spring 413 is connected.

Incidentally, 414 shown in FIG. 40 and FIG. 42 is the bearing 406, 4
A movable frame which holds 06 and moves integrally with the drive roller 372a, and 415 is a leaf spring which is attached to the movable frame 414 and urges the driven roller 372b toward the drive roller 372a.

Then, when the transport roller 407 that sends the paper P to the temporary stacking unit 352 is set at a position corresponding to the size of the paper P, both levers 411 are rotated by the biasing force of the spring 413. Move the movable frame 414,
It suffices to fit the bearings 406, 406 into the predetermined recess 410. In this way, the conveyance roller 407 can be moved very easily without using a tool such as a screwdriver at a position suitable for the size of the paper P, and the paper P can be collected in the temporary stacking unit 352 in an orderly stackable state. You can

Next, the gist of the present invention will be described. As described above, it is necessary to adjust the focus for each unit due to the variation in the focal length of the lens and the variation in the mounting position of the mirror and the like. This is a lens drive stepping motor 123
By controlling the respective rotation angles of the mirror driving stepping motor 105, the positions of the lens unit 54 and the mirrors 58, 59 (third optical unit 60) are changed. In addition, the leading edge of the image on the photosensitive drum 12 and the leading edge of the paper P often do not match due to variations in attachment of various components, and it is necessary to make adjustments by changing the start timing of the registration rollers 24. is there. These adjustments are performed by the microcomputer changing the rotation angle and the start timing of each motor based on the data stored in the memory.

FIG. 2 shows an example of the control circuit. 50 in the figure
Reference numeral 1 is a microcomputer that controls the entire copying apparatus (hereinafter simply referred to as a microcomputer), and 502 is the copy key 3
0, a decoder / input / output port to which the total counter key 33, the numeric keypad 34, and the like are connected, 503 is a display control unit that controls the first display unit 39, and 504 is a nonvolatile memory that stores adjustment values and the like regarding image forming operations. Memory, 505 is an input / output port for various signals necessary for copying operation, 506, 507, 508
Is a motor drive circuit for driving and controlling the stepping motors 105, 123, 307.

The operation in such a configuration will be described. In the present embodiment, in the ready state (“copy data” on the first display unit 39)
Is displayed), an adjustment mode is set by pressing a specific key in the numeric keypad 34, for example, the “0” key and the “5” key at the same time, and the first display section 39 displays the “test mode”. . Further, items stored in the non-volatile memory 504 and rewritable in this adjustment mode include a lens position, a mirror position, an image leading end position, and the like. The non-volatile memory 504 is, for example, a RAM (random access memory), and one word is assigned to each item, so that numeric values of “00 to 15” are stored. In this state, press the "0" key in the numeric keypad 34,
Next, by pressing the copy key 30, the microcomputer 501 accesses the address (for example, address 0) corresponding to the lens position in the non-volatile memory 504, and reads the data in that address. If the read data is, for example, “10”, the microcomputer 501 displays “Lens
"0" is displayed. When it is desired to change this value, for example, to change it to "9", the "501" key in the numeric keypad 34 is pressed next, and then the total counter key 33 is pressed. Write the numerical value "9" in the address and "Lensichi 09" on the 1st display 39.
Is displayed. Also, by pressing the "1" key in the numeric keypad 34 and then the copy key 30, the microcomputer 50
1 accesses an address (for example, address 1) corresponding to the mirror position in the non-volatile memory 504 and reads the data in the address. If the read data is, for example, "11", the microcomputer 501 displays "Mirror image 1" on the first display unit 39.
"1" is displayed. When changing this value to, for example, “10”, the microcomputer 501 also pushes the “1” and “0” keys in the ten-key pad 34, and then the total counter key 33, so that the microcomputer 501 sets the nonvolatile memory 504. The number "10" is written in the address No. 1, and the first display section 39 displays "Miraiichi 10". Similarly, by pressing the “2” key in the numeric keypad 34 and then the copy key 30, the microcomputer 501 accesses the address (for example, address 2) corresponding to the image leading end position in the nonvolatile memory 504. Then, the data in the address is read out and is displayed on the first display section 39 as "sentanichi XX" (XX is a numerical value from 00 to 15). This value can be similarly changed. After the adjustment is completed in this way, the microcomputer 501 is pressed by simultaneously pressing, for example, the “0” key and the “9” key on the numeric keypad 34.
Cancels the adjustment mode and returns to the ready state again, and the copying operation becomes possible.

In this way, the adjustment value is set by the operation from the operation panel without using the DIP switch etc. as in the past.
Since the lens position, mirror position, image tip position, etc. are adjusted, it is not necessary to open the cover each time, as in the past, making adjustments extremely easy and accurate and performing copy operations. You can make adjustments while doing so, which is very convenient.

In the above embodiment, the case where the invention is applied to an electronic copying apparatus has been described, but the present invention is not limited to this, and an image forming apparatus such as an electronic printer or a facsimile machine that requires adjustment regarding an image forming operation is used. If so, it can be applied.

[Advantages of the Invention] As described in detail above, according to the present invention, it is possible to provide an image forming apparatus in which the adjustment regarding the image forming operation can be performed extremely easily and accurately.

[Brief description of drawings]

1 is a plan view of an operation panel, FIG. 2 is a block diagram showing an example of a control circuit, and FIG. 3 is an external perspective view of a copying machine. FIG. 4 is a schematic vertical sectional front view of the copying apparatus, FIG. 5 is a schematic vertical sectional front view of the copying apparatus main body, FIG. 6 is a configuration explanatory view of the exposure optical apparatus, and FIG. 7 is a cooling air conducting path. FIG. 8 is a perspective view showing the operating means of the first and second optical units of the exposure optical apparatus, FIG. 9 is an explanatory view of the configuration of the same main portion, and FIG. 10 is a lens unit and a third unit of the exposure optical apparatus. FIG. 11 is a plan view showing the operating means of the optical unit, FIG. 11 is a schematic vertical sectional front view of the two-color developing device, and FIGS. 12 and 13 are views showing different operating states of the first developing unit, FIG. 14 and FIG. Figure 15 is the second
FIGS. 16 and 17 show different operating states of the developing unit, FIGS. 16 and 17 show operating states of the developing device, FIG. 18 shows a state in which the front cover of the copying device is opened, and FIG. 19 shows developer. FIG. 20 is a schematic vertical cross-sectional front view of the replenishing device, FIG. 20 is a schematic vertical side view of the developer replenishing device, and FIG. 21 is an explanatory diagram showing the opening / closing state of the developer discharge port when the container of the developer replenishing device is detached. FIG. 22 is a schematic plan view showing the structure around the developer receiving and conveying section of the second developing unit, FIG. 23 is a schematic sectional view of the developer replenishing device, and FIG. 24 is the same as the developer replenishing device. FIG. 25 is a schematic exploded perspective view, FIG. 25 is a schematic front view of the sheet feeding device section, FIG. 26 is a perspective view showing a state in which the cover of the sheet feeding cassette is removed, and FIG. 27 is a cassette which also serves as a manual sheet feeding tray. FIG. 29 is a perspective view of the cover, and FIG. 28 is a view showing a state in which the guide member of the manual feed tray is mounted and supported. FIG. 30 is a sectional view taken along the line EE of FIG. 28, FIG. 30 is a sectional view taken along the line ROLL of FIG.
FIG. 31 is a schematic perspective view of a support plate pushing-up mechanism that pushes up the support plate of the paper feed cassette, FIG. 32 is a schematic configuration explanatory view of the separating means, and FIG. 33 is an explanatory view showing a sheet separating state of the separating means.
FIG. 34 is an explanatory view showing the arrangement state of the paper non-detector in the paper feed cassette mounting portion, FIG. 35 is an explanatory view showing the drive system of the take-out roller and the registration roller, and FIG. FIG. 37 is a schematic plan view showing the structure of the roller contacting / separating means, FIG. 37 is a schematic front view showing the structure of the fixing device, FIG. 38 is a schematic vertical sectional front view of the direction changing conveying device, and FIG. 39 is a direction changing conveyer. FIG. 40 is a front view showing the configuration of the sheet distributing unit of the apparatus, FIG. 40 is a partially cutaway front view showing the configuration of the sheet carrying-in section to the temporary stacking section of the direction changing conveying apparatus, and FIG. Similarly, FIG. 42 is a partially cutaway side view of the main part of the sheet carry-in part. 1 ... Copier body, 6 ... Operation panel, P ... Paper,
12 ... Photosensitive drum, 13 ... Charging device, 14 ... Exposure optical device, 15 ... Developing device, 16 ... Transfer device, 20 ... Automatic paper feeding device, 24 ... Registration roller, 25 ... Fixing Equipment, 30 ...
... Copy key (first input means), 33 ... Total counter key (second input means), 34 ... Numeric keypad (third input means), 39 ... First display section (display means), 54 ... Lens Unit, 58,59 …… Mirror, 105 …… Mirror driving stepping motor, 123 …… Lens driving stepping motor, 307 …… Registry roller driving stepping motor, 501 …… Microcomputer, 502 …… Decoder / input / output port , 504 ... Non-volatile memory (storage means), 507-508 ...
… Motor drive circuit.

Claims (1)

[Claims] 1. An image forming means for forming an image on an image bearing member, a normal mode in which the image forming means forms an image, and various kinds of images used when the image forming means forms an image. In an image forming apparatus capable of switching between adjustment modes for changing initial setting data, an operation panel for operating the image forming apparatus, a numeric keypad provided on the operation panel, and at least a numerical value provided on the operation panel. A storage unit having a plurality of areas for storing initial settings for the image forming unit in association with a predetermined address; The image forming apparatus is switched from the normal mode to the adjustment mode by simultaneously pressing a plurality of keys of the first combination of the ten keys. In this adjustment mode, the stored contents of the address corresponding to the first numerical value input from the numeric keypad are read out from the storage area in the storage means and displayed on the display means, and the address corresponding to the first numerical value is displayed. The content of the storage area in the storage means is updated with the second numerical value input from the ten-key pad, and thereafter,
By simultaneously pressing a plurality of keys of a second combination different from the first combination of the ten keys, the image forming apparatus is switched from the adjustment mode to the normal mode and stored in the storage means. An image forming apparatus comprising: a control unit that changes the initial setting of the image forming apparatus and returns the image forming apparatus to a state in which an image forming operation is possible.