JP2001255728A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect the proper attachment of a toner cartridge unit without electrical contact in an image forming device. SOLUTION: This image forming device possesses a developing unit 4, the toner cartridge unit 17 provided in each developing unit 4 in an attachable/ detachable and also exchangeable state, a slit disk 23 which is provided at each toner cartridge, unit 17 and is attached on the shaft of the rotary shaft 21 of a paddle, and in which slits are formed with specified intervals in a peripheral direction and slit intervals are mutually differently formed, a slit disk detection signal generating part provided corresponding to each slit disk 23 and to generate the pulse signal of the slit of the slit disk 23 that is provided with a photosensor to detect the slit of the slit disk 23 and is rotated and an IO controlling part to detect the kind of the attached toner cartridge unit 17 of the slit disk 23 from the pulse signal at the slit disk detection signal generating part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus having a toner cartridge unit.

[0002]

2. Description of the Related Art An image forming apparatus is often used as a copying machine, and in recent years, a color image forming apparatus has become widespread.

Here, a conventional color image forming apparatus will be described.

The image forming apparatus is provided with four image forming units for forming a black image, a cyan image, a magenta image and a yellow image, respectively.

Each image forming unit has a photosensitive drum as an image carrier. Around the photosensitive drum, a charger for uniformly charging the surface of the photosensitive drum, and toner is applied to the photosensitive drum by a developing roller. A developing device that supplies the electrostatic latent image to visualize the image and a first transfer roller that transfers the toner image to the intermediate transfer member are provided. A developing device having a toner supply roller is provided with a detachable and replaceable toner cartridge unit.

Above the image forming unit, a laser unit for irradiating each photosensitive drum with light according to image information is arranged. Further, below the image forming unit, an endless intermediate transfer belt that is pressed against the photosensitive drum by the first transfer roller is disposed.

Below the intermediate transfer belt, a cassette in which sheets are stored is provided. A pickup roller for picking up the sheets in the cassette one by one, a registration roller for transferring the picked-up sheet to the intermediate transfer belt at a predetermined timing, and an intermediate transfer belt are formed on the transfer path of the paper extending from the cassette. A second transfer roller for transferring the transferred toner image to the paper, a fixing device for fixing the transferred toner image to the paper, a paper discharge port for discharging the paper on which the toner image is fixed, and a paper discharge port for discharging the paper. A discharge tray in which the stacked sheets are stored is sequentially arranged.

In the image forming apparatus having the above configuration, a latent image of a black component color is first formed and visualized as a black toner image, and the black toner image is transferred to the intermediate transfer belt by the first transfer roller. Is done. While the black toner image is being transferred, the cyan toner image is visualized,
Superimposed on the black toner image. Hereinafter, image formation is similarly performed for the magenta toner image and the yellow toner image, and the superposition of the four color toner images on the intermediate transfer belt is completed.

When the color toner image is formed on the intermediate transfer belt as described above, the sheet is sent to the intermediate transfer belt by the registration roller, and the four color toner images are transferred onto the sheet by the second transfer roller. , And a full-color image is obtained.

Thereafter, the toner is heated and melted by the heating roller of the fixing device, the toner image is fixed on the paper, and the paper is discharged from the paper discharge port to the paper discharge tray, thereby completing printing.

[0011]

In the conventional image forming apparatus described above, since the toner cartridge unit is a consumable item and optional, there is a concern that a user may mistakenly mount or form an image without mounting.

In order to prevent such a risk, in a conventional image forming apparatus, a substrate is mounted in a toner cartridge unit and an ID from an EEPROM is stored.
By reading the data, the proper mounting of the toner cartridge unit was recognized.

However, it has been difficult to secure a space for mounting the substrate in the toner cartridge unit.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an image forming apparatus capable of detecting proper mounting of a toner cartridge unit without relying on electrical contact.

[0015]

In order to solve this problem, an image forming apparatus according to the present invention is provided with a photosensitive member provided corresponding to a developing color and forming an electrostatic latent image corresponding to the developing color. ,
A developing device that is provided for the photoconductor and supplies toner to the photoconductor by a developing roller to visualize the electrostatic latent image; Is provided in the toner cartridge unit, the slit cartridge is provided on the toner cartridge unit, is mounted on the axis of the rotating body and has slits formed at predetermined intervals in the circumferential direction, provided corresponding to the slit disk, A slit disc detection signal generator that generates a pulse signal corresponding to the slit of the rotating slit disc with a photo sensor that detects the slit of the slit disc, and the slit disc is attached from the pulse signal at the slit disc detection signal generator. And a detector for detecting the type of the toner cartridge unit.

This makes it possible to detect the proper mounting of the toner cartridge unit without the need for electrical contact, based on the pulse signal associated with the slit interval in the slit board of the toner cartridge unit.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention is provided for a photosensitive member provided corresponding to a developing color, on which an electrostatic latent image corresponding to the developing color is formed, and for the photosensitive member. ,
A developing device that supplies toner to a photoreceptor by a developing roller to visualize an electrostatic latent image, and a toner cartridge that is provided in a detachable and replaceable state with respect to the developing device and is filled with toner for replenishment Unit and a slit disk provided on the toner cartridge unit and mounted on the axis of the rotating body and having slits formed at predetermined intervals in the circumferential direction, and provided corresponding to the slit disk to detect the slit of the slit disk A slit disc detection signal generator for generating a pulse signal corresponding to the slit of a rotating slit disc provided with a photo sensor to rotate, and a toner cartridge unit on which the slit disc is mounted is obtained from the pulse signal at the slit disc detection signal generator. An image forming apparatus having a detection unit for detecting the type of the toner cartridge. The pulse signal according to a distance, has the effect of making it possible to detect a proper mounting of the toner cartridge unit without due to electrical contact.

According to a second aspect of the present invention, a plurality of photoconductors are provided corresponding to a development color, and a photoconductor on which an electrostatic latent image corresponding to the development color is formed; Developing devices that supply toner to the photoreceptor by a developing roller to visualize the electrostatic latent image are provided for each developing device in a detachable and replaceable state, and are filled with toner for replenishment. A toner cartridge unit, a slit disc provided in each toner cartridge unit, mounted on a shaft of a rotating body, and formed with slits formed at predetermined intervals in a circumferential direction and formed with different intervals from each other, A slot that is provided corresponding to each slit board and has a photo sensor that detects the slits of the slit board and generates pulse signals corresponding to the slits of the rotating slit board. A disc detection signal generation unit, and a detection unit that detects a type of the toner cartridge unit to which the slit disc is attached from a pulse signal in the slit disc detection signal generation unit. The difference in the pulse signal resulting from the difference in the slit interval in the slit disc has an effect that it is possible to detect the proper mounting of the toner cartridge unit without relying on electrical contact.

According to a third aspect of the present invention, there is provided an image forming apparatus according to the second aspect, wherein the plurality of slit discs have an equal interval between the respective slits and a different number of slits. The type of the toner cartridge unit provided with the predetermined slit disk can be determined based on the difference in the number of generated pulses, and the proper mounting of the toner cartridge unit can be detected without electrical contact. Having.

According to a fourth aspect of the present invention, there is provided an image forming apparatus according to the second aspect, wherein the plurality of slit discs have the same number of slits because the intervals between the slits are unequal. The type of the toner cartridge unit with the predetermined slit disk attached can be determined based on the difference between the repeated waveform patterns,
This has the effect that the proper mounting of the toner cartridge unit can be detected without using electrical contact.

According to a fifth aspect of the present invention, there is provided an image forming apparatus according to the second aspect, wherein the plurality of slit discs have an uneven interval between each slit and a different number of slits. Yes, it is possible to determine the type of toner cartridge unit with a predetermined slit disk attached based on the difference in the number of generated pulses or the repeated waveform pattern, and to detect proper mounting of the toner cartridge unit without electrical contact. Has the effect that it becomes possible.

According to a sixth aspect of the present invention, there is provided an image forming apparatus according to the third aspect, wherein two sets of photosensors are installed at mutually different positions in the rotation direction of the slit disc. In the case of mounting, there is a period in which the pulse signals obtained from the two sets of photosensors are simultaneously at the High level, so that it is possible to determine the type of the toner cartridge unit on which the slit disk is mounted and the erroneous mounting. This has the effect that the proper mounting of the toner cartridge unit can be detected without using electrical contact.

Hereinafter, an embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG. In these drawings, the same members are denoted by the same reference numerals, and duplicate description is omitted.

FIG. 1 is a schematic view showing an image forming apparatus according to an embodiment of the present invention, FIG. 2 is a sectional view showing a developing unit and a toner cartridge unit mounted on the image forming apparatus shown in FIG. 1, and FIG. FIG. 4 is a partial perspective view of the developing device and the toner cartridge unit of FIG. 2, FIG. 4 is a circuit diagram showing a detection circuit of a slit disk attached to the toner cartridge unit of FIG. 2, and FIG. 5 is a slit disk attached to each toner cartridge unit FIG. 6 is an explanatory view showing an example of the slit pattern and a square wave signal Vb converted from the slit pattern. FIG. 6 shows a slit pattern of a slit board attached to each toner cartridge unit and a square wave signal Vb converted from the slit pattern.
FIG. 7 is an explanatory view showing another example of the slit pattern of the slit disk attached to each toner cartridge unit, and FIG. 8 is an explanatory view showing still another example of the square wave signal Vb converted from the slit pattern. FIG. 9 is an explanatory view showing still another example of a slit pattern of a slit board attached to each toner cartridge unit and a square wave signal Vb converted from this slit pattern. FIG. 9 is an explanatory view showing an erroneous mounting detection pattern in FIG. It is.

In the image forming apparatus 1, a black image forming unit 29 for forming a black image, a cyan image forming unit 30 for forming a cyan image, a magenta image forming unit 31 for forming a magenta image, and a yellow image are formed. The four image forming units of the yellow image forming unit 32 are arranged.

Each image forming unit 29, 30, 31, 3
2 has a photoconductor drum (photoconductor) 3 as an image carrier having a photoconductive layer on the outer peripheral surface, and around it,
A charger 14 for uniformly charging the surface of the photosensitive drum 3;
A developing device 4 for supplying toner to the photosensitive drum 3 by the developing roller 5 to visualize the electrostatic latent image and a first transfer roller 7 for transferring the toner image to the intermediate transfer member 6 are provided.

Here, a toner cartridge unit 17 is mounted on the developing device 4 having the toner supply roller 18 in a detachable and replaceable state. Then, the toner 19 in the toner cartridge unit 17 is supplied to the developing roller 5 as needed by the rotation of the toner supply roller 18.

Image forming units 29, 30, 31, 32
A laser unit 2 for irradiating each photosensitive drum 3 with light corresponding to image information is provided above the laser oscillator, a polygon mirror or a lens.

These image forming units 29, 30, 3
Below the first and second rollers 32, an endless intermediate transfer belt 6 that is supported by a plurality of rollers 33, rotates in the direction of the arrow, and is pressed against the photosensitive drum 3 by a first transfer roller 7 is disposed. . A cleaning member 15 is disposed in contact with the outer peripheral surface of the intermediate transfer belt 6 to remove residual toner on the intermediate transfer belt 6.

Below the intermediate transfer belt 6, a sheet 13
Is installed.

On the conveyance path of the paper 13 extending from the cassette 10, a pickup roller 11 for taking out the paper 13 in the cassette 10 one by one, and the paper 13 taken out by the pickup roller 11 are timed to the intermediate transfer belt 6. The resist roller 16 to be conveyed and the second to transfer the toner image formed on the intermediate transfer belt 6 to the paper 13
The transfer roller 8, a fixing device 9 for fixing the transferred toner image to the paper 13, a paper discharge port 20 for discharging the paper 13 with the toner image fixed thereon, and a sheet 13 discharged from the paper discharge port 20 are accumulated. The paper discharge trays 12 are sequentially arranged.

In the image forming apparatus configured as described above, first, a black component color latent image is formed in the black image forming unit 29 and visualized as a black toner image. The black toner image is transferred to the belt 6.

While the black toner image is being transferred to the intermediate transfer belt 6, the cyan toner image is visualized by the cyan image forming unit 30.
It is superimposed on the black toner image transferred above. Hereinafter, image formation is performed in the same manner on the magenta toner image and the yellow toner image.
The superposition of the color toner images is completed.

On the other hand, while the toner image is being formed as described above, the sheet 13 is taken out of the cassette 10 by the pickup roller 11 and stopped at the position where the end portion is sandwiched between the registration rollers 16. When the superposition of the four color toner images on the intermediate transfer belt 6 is completed, the sheet 13 is moved by the registration roller 16 to the intermediate transfer belt 6.
The toner images of four colors are collectively transferred and conveyed onto the paper 13 by the second transfer roller 8 to which the transfer bias is applied, and a full-color image is obtained.

Thereafter, the toner is heated and melted by the heating roller of the fixing device 9 to fix the toner image on the paper 13.
The paper is discharged from the paper discharge port 20 to the paper discharge tray 12 and printing is completed.

As shown in FIG. 2, a toner cartridge unit 17 filled with toner 19 for replenishment is fixed to a rotating shaft (rotary body) 21 and agitates the toner 19 to supply the toner 19 to a toner replenishing roller. Paddle 2 to send to 18
2 are installed. When the remaining amount of toner in the developing device 4 is detected to be small by a toner remaining amount detection sensor (not shown) provided in the developing device 4, the paddle 22 attached to the rotating shaft 21 by the main body of the apparatus. Subsequently, the toner supply roller 18 is driven to rotate, and the toner 19 in the toner cartridge unit 17 is supplied to the developing device 4. As a result, the toner 19 in the developing device 4 is always maintained at a predetermined amount or more, and the toner 19 is stably supplied to the developing roller 5.

Here, as shown in FIG. 3, a slit disk 23 having slits formed at predetermined intervals in the circumferential direction is mounted on the rotating shaft 21. Therefore, the paddle 22 is rotated by the rotating shaft 21 to stir the toner 19.
Is rotated, the slit disc 23 is also rotated accordingly. In order to detect the rotation of the slit board 23, a photo sensor is provided on the apparatus main body side. In the present embodiment, the slit disc 23 is mounted on the axis of the rotary shaft 21 of the paddle 22,
It can also be mounted on other rotating bodies.

It should be noted that the slit discs 23 of the respective toner cartridge units 17 in which black toner, cyan toner, magenta toner and yellow toner are respectively stored.
, The slit patterns are different from each other (see FIGS. 5 and 6).

The detection of the rotation of the slit board 23 will be described with reference to an example in which a photo-interrupter, which is a transmission sensor, is used as a photo sensor. As the photo sensor, a transmission sensor other than the photo interrupter or various reflection sensors may be used.

In FIG. 4, the detection circuit of the slit board 23 is attached to each of the toner cartridge units 17 and a slit board detection signal generator 28 for detecting a slit pattern of the rotating slit board 23 and generating a detection signal. The memory 27 in which the slit pattern of the slit board 23 is stored, the detection signal in the slit board detection signal generation unit 28, and each slit pattern stored in the memory 27 are input, and these slit patterns and the detection signal are compared. IO for detecting the type of the toner cartridge unit 17 to which the slit board 23 is attached
And a control unit (detection unit) 26. Then, the device such as the display device 27 is controlled according to the device control signal output from the IO control unit 26.

The slit board detection signal generation section 28 is a photo interrupter 129 which is a photo sensor for detecting a slit pattern of the slit board 23, and converts a slit board detection signal from the photo interrupter 129 into a square wave signal Vb to perform IO control. And a comparator 25 for outputting to the section 26.

5 to 9, each of the slit discs 23 attached to the four toner cartridge units 17 is provided.
Rotates at substantially the same speed in the direction of arrow R with the rotation of the paddle.

As shown in the figure, the slit patterns between the slit disks 23 are different from each other. By detecting the difference between the slit patterns, the toner cartridge unit 17 to which the slit disk 23 is attached is detected. It has become.

Here, in FIGS. 5, 8 and 9, in addition to the fact that the slit intervals between the slit disks 23 are different, the intervals between the slits in each of the slit disks 23 are uniform. In FIGS. 8 and 9, the number of slits between the slit disks 23 is the same in FIGS.

In FIG. 6, in addition to the fact that the slit intervals between the slit disks 23 are different, the intervals between the slits in each of the slit disks 23 are unequal, and the number of slits between the slit disks 23 is different. Are the same.

Further, in FIG.
In addition to the different slit spacing between each other,
The intervals between the slits in each of the slit discs 23 are unequal, and the number of slits between the slit discs 23 is different.

8 and 9, slits are detected by two sets of photointerrupters 129 installed at mutually different positions in the rotation direction of the slit disk 23.

In these drawings, the positional relationship between the slit of the slit board 23 and the photo interrupter 129 is set as the operation origin, and the square wave signal V
The relationship between b and the elapsed time t on the horizontal axis is shown. Also,
(Y), (M), (C), and (K) correspond to four colors of yellow, magenta, cyan, and black, respectively. Further, in FIGS. 8 and 9, (Y1), (Y
2), (M1), (M2), (C1), (C2), (K
1) and (K2) show the distinction between the two sets of photointerrupters 129.

In the illustrated case, the slit disc 23 is rotated counterclockwise, but may be rotated clockwise.

As described above, in FIG. 5, the slit plate 23 attached to the four-color toner cartridge unit is used.
Are different in the slit interval between the slit disks 23, the intervals between the slits in each slit disk 23 are equal, and the number of slits between the slit disks 23 is different.

According to this, since the number of slits passing through the photointerrupter 129 per predetermined time is different between the slit discs 23, the number of generated pulses and the generated pulse interval of the square wave signal Vb are also different from each other. In the case shown in the figure, the number of generated pulses after the lapse of the specific time t1 is 2 pulses by the yellow slit disc 23,
4 pulses on the magenta slit plate 23, 6 pulses on the cyan slit plate 23, and 8 pulses on the black slit plate 23).

Therefore, it is possible to determine the type of the toner cartridge unit to which the slit board 23 is attached based on the difference in the number of generated pulses, and it is possible to detect the proper mounting of the toner cartridge unit without making electrical contact. Become.

In FIG. 6, the slit disc 23 attached to the four-color toner cartridge unit is
3, the intervals between the slits are different from each other, the intervals between the slits in each of the slit discs 23 are uneven,
The number of slits between the slit boards 23 is the same.

According to this, since the repetitive waveform pattern in the square wave signal Vb is different, the type of the toner cartridge unit can be determined by detecting one cycle of the signal, and without the need for electrical contact. It is possible to detect the proper mounting of the toner cartridge unit. Even when the number of generated pulses in the square wave signal Vb is one in one rotation of the slit board 23 as a repetitive waveform pattern, the type of the toner cartridge unit is determined based on the difference in the generation time of the one pulse. Thus, the proper mounting of the toner cartridge unit can be detected without using electrical contact.

In FIG. 7, the slit disc 23 attached to the four-color toner cartridge unit is
3 are different from each other, the intervals between the slits in each slit board 23 are not uniform, and the number of slits between the slit boards 23 is different.

According to this, since the number of slits passing through the photointerrupter 129 per predetermined time differs between the slit discs 23, the number of generated pulses of the square wave signal Vb also differs from each other (as shown in the figure). , The number of pulses generated in one rotation operation is 2 pulses in the yellow slit disk 23 and 2 pulses in the magenta slit disk 2.
3 for 3 pulses, cyan slit board 23 for 4 pulses, black slit board 23 for 5 pulses). The repetitive waveform pattern of the square wave signal Vb is also different. Therefore, the type of the toner cartridge unit to which the slit board 23 is attached can be determined based on the number of generated pulses or the difference in the repetitive waveform pattern, and the proper mounting of the toner cartridge unit can be detected without electrical contact. Becomes possible.

In FIG. 7, the pulse with the smallest pulse width is used as the reference pulse F in one rotation operation.

8 and 9, the slit discs 23 attached to the four color toner cartridge units have different slit intervals between the slit discs 23.
The intervals between the slits in each slit board 23 are equal, and the number of slits between the slit boards 23 is the same. Also,
Two sets of photo-interrupters 129 are provided at mutually different positions in the rotation direction of the slit board 23, and these photo-interrupters 129 detect slits.

That is, FIG. 8 shows yellow, magenta,
This is a detection waveform of the square wave signal Vb when there is no erroneous mounting in the toner cartridge units of all four colors of cyan and black. In this case, in the toner cartridge units of any colors, the square wave signals Vb (1) and Vb (2) are simultaneously set to H during the rotation operation of the slit board 23.
It does not go to the high level.

FIG. 9 shows a detection waveform of the square wave signal Vb when the magenta (M) toner cartridge unit is mounted at the cyan (C) mounting position as an example in which the erroneous mounting of the toner cartridge unit occurs. Show.

In FIG. 9, the square wave signal Vb (1) and the square wave signal Vb (2) obtained from the two sets of photointerrupters 129 (C1) and 129 (C2) are simultaneously Hi.
There is a period D during which the gh level is reached.

As described above, in the case of erroneous mounting, the square wave signals Vb (1) for the toner cartridges of all four colors are used.
And Vb (2) are simultaneously at the High level during a period D, whereby it is possible to determine the type and erroneous mounting of the toner cartridge unit to which the slit board 23 is attached, and to determine the toner cartridge without electrical contact. It is possible to detect proper mounting of the cartridge unit.

[0063]

As described above, according to the present invention, it is possible to obtain an effective effect that it is possible to detect proper mounting of the toner cartridge unit without relying on electrical contact.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an image forming apparatus according to an embodiment of the present invention;

FIG. 2 is a sectional view showing a developing unit and a toner cartridge unit mounted on the image forming apparatus of FIG. 1;

FIG. 3 is a partial perspective view of the developing device and the toner cartridge unit of FIG. 2;

FIG. 4 is a circuit diagram illustrating a detection circuit of a slit board attached to the toner cartridge unit of FIG. 2;

FIG. 5 is an explanatory diagram showing an example of a slit pattern of a slit board attached to each toner cartridge unit and a square wave signal Vb converted from the slit pattern.

FIG. 6 is an explanatory view showing another example of a slit pattern of a slit board attached to each toner cartridge unit and a square wave signal Vb converted from the slit pattern.

FIG. 7 is an explanatory view showing still another example of a slit pattern of a slit board attached to each toner cartridge unit and a square wave signal Vb converted from the slit pattern.

FIG. 8 is an explanatory diagram showing still another example of a slit pattern of a slit board attached to each toner cartridge unit and a square wave signal Vb converted from the slit pattern.

FIG. 9 is an explanatory diagram showing an erroneous mounting detection pattern in FIG. 8;

[Explanation of symbols]

 Reference Signs List 3 photoconductor drum (photoconductor) 4 developing device 5 developing roller 17 toner cartridge unit 19 toner 21 rotating shaft (rotating body) 22 paddle 23 slit board 26 IO control section (detection section) 28 slit board detection signal generation section 129 photo interrupter (Photo sensor)

Claims (6)

[Claims] A photosensitive member provided corresponding to a developing color and forming an electrostatic latent image corresponding to the developing color; and a photosensitive member provided for the photosensitive member and supplying toner to the photosensitive member by a developing roller. A developing device that visualizes the electrostatic latent image; a toner cartridge unit that is detachably and replaceably provided to the developing device and is filled with toner for replenishment; A slit disk attached on the axis of the rotating body and having slits formed at predetermined intervals in a circumferential direction; and a photosensor provided corresponding to the slit disk and detecting a slit of the slit disk. A slit disc detection signal generating unit for generating a pulse signal corresponding to the slit of the rotating slit disc, and the slit from the pulse signal in the slit disc detection signal generating unit. An image forming apparatus, comprising a detector for detecting a type of the toner cartridge unit mounted with preparative plate. 2. A plurality of photoconductors, each of which is provided in correspondence with a development color and on which an electrostatic latent image corresponding to the development color is formed, and a photoconductor provided for each of said photoconductors, wherein toner is applied to said photoconductor by a development roller. A developing unit for supplying the electrostatic latent image to visualize it, a toner cartridge unit provided in each of the developing units in a detachable and replaceable state and filled with toner for replenishment, A slit disc which is provided on the toner cartridge unit, is mounted on a shaft of a rotating body, and has slits formed at predetermined intervals in a circumferential direction and the intervals are different from each other; And a photosensor for detecting a slit of the slit disk, and generating a pulse signal corresponding to the slit of the slit disk rotating. An image forming apparatus comprising: a lit board detection signal generation section; and a detection section that detects a type of the toner cartridge unit to which the slit board is attached from the pulse signal in the slit board detection signal generation section. apparatus. 3. The image forming apparatus according to claim 2, wherein the plurality of slit discs have an equal interval between the slits and a different number of slits. 4. The image forming apparatus according to claim 2, wherein the plurality of slit discs have an equal interval between the slits and the same number of slits. 5. The image forming apparatus according to claim 2, wherein the plurality of slit discs have unequal intervals between the slits and different numbers of slits from each other. 6. An image forming apparatus according to claim 3, wherein two sets of said photosensors are installed at mutually different positions in the rotation direction of said slit disc.