JPS5859485A - Cleaning device for electronic copying machine - Google Patents

Abstract

PURPOSE:To carry a toner efficiently without damaging the surface of a photoreceptor, by providing a coil spring, whose diameter is larger than the width of the aperture part of a casing, in the casing into which the toner scraped by a blade pressed to the surface of the phtoreceptor is gathered. CONSTITUTION:A cleaner unit 6 supports a photosensitive drum 2 with its both side plates and is attachable to and detachable from a copying machine main body as one body together with the drum 2. A blade member 61 is held by a blade holding means 65 which can be turned around a supporting shaft 64, and the holding means 65 is energized counterclockwise through a pin 67, which is projected to the outside of a casing 66, by a spring 68. The outside diameter of a coil spring 20 for toner carrying of a toner carrying means 70 is made larger than the width of an aperture part 72a of a toner gathering casing 72 where this coil spring 20 is stored. Consequently, the toner is carried efficiently by the coil spring without damaging the surface of the photoreceptor.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a cleaning device for an electronic copying machine, and more particularly to a cleaning device for an electronic copying machine, and more specifically, a cleaning device for scraping off toner with a blade member pressed against the surface of a photoreceptor, collecting and conveying the toner. The present invention relates to a cleaning device.

BACKGROUND OF THE INVENTION Generally, a blade-type cleaning device reuses toner by collecting toner scraped off by a blade and returning it to a developing device. In addition, it has the advantage that the device can be made smaller than other rotating brush or paper web types, and has been adopted in many copying machines in recent years. This type of blade-type cleaning device requires a small and highly efficient mechanism for collecting the scraped toner and transporting it outside the cleaning device. For this reason, devices have been proposed or provided that utilize the conveying force associated with the rotation of a spiral shape.

However, if the spiral is formed by a rigid body,
Although the conveyance condition is relatively stable, in order to change the direction of toner conveyance, a connecting mechanism is required in the direction changing section, which has the disadvantage that toner conveyance failures and leaks are likely to occur in this connecting mechanism. It has the disadvantage of high cost. Therefore, it is conceivable to use a flexible member such as a coil spring to convey the toner to give the toner conveyance path a certain degree of freedom. When the spring is exposed to a load, the spring is likely to be partially bent and deformed, and if the cleaning device is placed close to the photoconductor, this may damage the surface of the photoconductor. Yes, it's not good.

Purpose The present invention has been made with attention to these points, and it is an efficient method that does not impair the advantages of using a coil spring for toner transport, does not cause any inconveniences such as damaging the surface of the photoconductor, It is an object of the present invention to provide a cleaning device that can transport toner.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view schematically showing the configuration of an electronic copying machine (1) equipped with a cleaning device of the present invention. 3), developing device (4), charger for transfer and weight removal (5)
), cleaner unit (6), eraser lamp (power, etc.) are arranged in this order.

The document table (8
) An original (not shown) is placed on the original placing plate (81) made of a transparent member by an exposure lamp (91) and reflecting mirrors (92) and (93) provided on the lower surface of the original table.

An optical system (9) consisting of a lens (94) etc. scans the image as the document table (8) moves and projects it onto the exposure area (E) on the rotational circumference of the photosensitive drum (2).

Copy papers (Pl) are stacked and held in a cassette (C), and are fed one by one from the top one by the rotation of the paper feed roller (10), and once stopped by the timing roller (11). , are conveyed in synchronization with the image formed on the surface of the photoreceptor drum (2), and transferred to the transfer charger (51).
), the powder image is transferred to the photoreceptor drum (2) by the electron removal charger (52), and then transferred to the conveyor belt (12).
) is conveyed to the heat roller fixing device (3), and after the image is fixed, it is discharged onto a tray (15) by a discharge roller (14).

As shown in FIG. 2 (al), the main body frame of the copying machine (1) whose outline has been explained above consists of an upper frame (lot) and a lower frame (102) so that the copy paper conveyance path can be opened.
Both frames are connected by a support plate (103), and the upper frame (1o1) is connected to the lower frame (1o1).
02), it is configured to be rotatable around a fulcrum (104).

The main purpose of this configuration is to open the passage when copy paper (P) jams in the conveyance path so that the jammed paper can be easily removed. ), the attachment and detachment of the cleaner unit (6) to and from the main body is also carried out with the upper and lower seven frames (101) and (102) open, as shown in FIG. Upper and lower frames (101), (102
) may be biased in the opening angle direction by a biasing means such as a torsion bar (130), and when closed, the upper frame (1
The closed state is locked and maintained by a hook lever (105) provided on the lower frame (102) and a pin (106) fixed to the lower frame (102). Torsion bar (130) '(7)
The shape is as shown in FIG. 2 tbl, and this type of biasing means may be provided as necessary to facilitate the opening angle operation of the upper frame (101).

Regarding this lock mechanism, the copying machine (1) is equipped with a safety mechanism as shown in FIGS. 3 and 4.

Mechanical devices such as copying machines are generally configured so that the main body side plate can be opened to inspect the inside of the machine or replace consumables, and is provided with a safety switch that turns off the power circuit, etc. by opening the side plate. The copying machine (1) also has a microswitch (S) on the upper frame (10).
W) is provided so that the switch operating piece (108a) of the operating member (108) fixed to the exterior cover (107) can go in and out of the opening (109a) of the switch cover (109), and the exterior cover (107) is closed. When the cover (109
) and activate the micro switch (SW).
The power supply circuit (not shown) can be turned on.

On the other hand, the aforementioned hook lever (105) is attached to the upper frame (
1 (H), and is biased counterclockwise in FIG. 3 by a torsion spring (110), and is fixed to the shaft (105a). The engagement with the pin (106) is released by operating the lock release plate (111). However, if you try to open the upper and lower frames while the exterior cover (j07) is closed, the operating member (10
8) and the exterior cover (107) itself, which is extremely inconvenient in terms of safety. Therefore, in the copying machine (1), when the outer cover (107) is closed, the hook lever 005) is prevented from rotating and the upper and lower frames (101) are closed.

(102) is configured so that it cannot be opened. That is, as shown in FIGS. 3 and 4, the shaft (169) is attached to the side surface of the cover (169).
A regulating plate (112) rotatably supported by the regulating plate (13) is provided, and the regulating plate actuating piece (108b) of the aforementioned actuating member (108) is provided.
) in the clockwise direction in Fig. 3, and with the exterior cover (107) closed, the hook lever L
(105) is prevented from rotating. Regulation plate (11
2) is biased counterclockwise in FIG. 3 by a torsion spring (114), and when the side plate (107) is opened, the regulation of the hook lever' (1os) is divided by 1, and the hook lever (105) and pin (106) can be disengaged. Fig. 4 111 shows a state in which the exterior cover (107) is open and the rotation restriction of the hook lever (105) by the regulation plate (112) is released, and Fig. 4 (bl) shows a state in which the side plate (107) is closed. It shows the state at the time.

To further explain Figs. 1 and 2, copying machine (1)
has a blade member (61) in the cleaner unit (6), and is configured to bring the blade member (61) into pressure contact with the surface of the photosensitive drum (2) to scrape off residual toner after transfer. Preferably, the blade member (61) is spaced apart from the photoreceptor drum (2) when the photoreceptor drum (2) is in a removable state. For this reason, copying machine (1)
has a blade approach/separation mechanism as shown below.

According to FIG. 5(a) and FIG. 6, first, the cleaner unit (
6) will be explained.

The cleaner unit (6) has both side plates (62), (6
3) to support the photoreceptor drum (2) by the side plate (62).

(63) has stepped portions (62a) and (63a), and is configured to be detachable from the photosensitive drum (2) integrally with the main body of the copying machine.

The blade member (6J) is held by a blade holding means (65) that is rotatable about a support shaft (64),
The holding means (65) is always supported by a spring (68) via a pin (67) protruding outside the casing (66).
64) in a counterclockwise direction.

The toner scraped from the surface of the photoreceptor by the blade member (61) is transferred to the toner conveying means (
70) and transported out of the unit. The toner conveyance means (70) includes a coil spring (71) for conveyance, a coil casing (72) having a cylindrical passage with a diameter slightly larger than the outer diameter of the coil spring (71), and the like. By appropriately rotating the spring (71), the toner is carried out of the unit. As shown in Figures 1 and 6, coil springs (
7]) through the hose (73) and the developing device (4).
), the toner may be returned to the inside of the container so that the toner can be reused. The cleaner unit (6) transports such toner.
This can be achieved with a continuous coil spring from within.

Both (74) and (75) are sealing films, and the film (74) is particularly thin, about 50 mm in diameter, and its tip is brought into contact with the surface of the photoreceptor drum (2). In this way, the Ashidome toner on the surface of the photoconductor does not fall off even when it comes into contact with the film (74), and the toner scraped off by the blade member (61) is transmitted along this film (74) to the coil casing (72). ) is dropped inside. The opening (72) of this coil casing (72)
In a), the inside diameter of the opening is smaller than the outer diameter of the coil spring (71). As a result, even if the coil spring (71) is twisted, the coil spring (71) can be prevented from protruding from the casing and damaging the surface of the photoreceptor or the film (74).

The blade holding means (65) includes side plates (62), (6
3), which is rotatably supported by a support shaft (64).
), the receiver is rotatably held on the base (76) with a screw (77), and the receiver is a plate (78), and the blade member (61) is sandwiched between the plate (78). Holding plate (7
9), etc., and the screw (77) is located approximately in the center of the plate (78) in the axial direction of the photoreceptor drum (2), and the holding plate (79) is secured on both sides by screws, etc. (not shown). The receiver is pressed and fixed to the plate (78).

The cleaning device for a copying machine according to the present invention has the above-described configuration, and the setting conditions of the blade member (61) will be further explained.

As shown in FIG. 5 tbl, the blade member (61) is bent to the solid line position as the photosensitive drum (2) rotates. The actual cleaning effect is determined by the relationship between the blade member (61) and the photoreceptor ram (2) in this bent state, and the pressure contact angle ( 9)), pressure contact force (F), blade member hardness CI), etc.

The contact angle (α) is the tangent line (Yl) at the contact point (1) between the blade member (61) and the photoreceptor drum (2) when the photoreceptor drum (2) rotates, and the tangent line (Yl) at the contact point (1) between the blade member (61) and the photoreceptor drum (2) when the photoreceptor drum (2) rotates, and the tangent line (Yl) between the contact point (1) and the blade member (61).
The reference position fsl in this case is a point 5 points from the tip of the blade member (61). Pressure angle (α)
(If it is too large, the uniform contact between the tip of the blade member (61) and the surface of the photoreceptor drum (2) will be poor, and if it is too small, the toner blocking force will tend to be weak. According to experiments, it was confirmed that the pressure contact angle α) is preferably in the range of 60°≦α≦80°.

In the case of the above embodiment, the pressure contact angle α) is set to 72°.

Pressure contact force (F) is applied to the contact point (1) and the blade holding means (65)
This is an apparent force within the contact point that is considered to act in a direction perpendicular to the line connecting the support shaft (64) of
) becomes small, and if it is too weak, there will be problems such as poor uniform contact. According to experiments conducted by the inventors, the contact force f
F) is the thickness of the blade ([) is 5 mm, and the protrusion amount (t) is 1
When 9mm, 5g weight/throat ≦ F ≦ 11g@/
It was confirmed that it is preferable to have it in the throat area.

In the above embodiment, the pressure contact force (F) is set to 6 g'a/-.

The hardness ([1) of the blade member (61) is JI'S
It refers to the hardness measured by durometer A specified in K 6301, etc., and as the hardness (Hl) increases, the toner blocking force, that is, the force for removing toner increases, but the uniform contact with the photoreceptor surface deteriorates. When the hardness (I) is low, the toner blocking force is poor, and there is a disadvantage that the deflection is large against a similar pressure contact force.According to experiments, the hardness (Jl) is 65 degrees ≦) -1 ≦ 78 degrees. It was confirmed that it is preferable to fall within the range of .

In the above embodiment, an angle of 73 degrees is used.

Furthermore, as is clear from the above explanation, these pressure contact angles (a
! l, pressure contact force (F), hardness 1), etc. have a correlation with each other, and an appropriate combination of values may be determined within the above-mentioned appropriate range.

Next, the blade approach and separation mechanism of the copying machine will be explained.

The blade contact/separation mechanism (200) is a cleaner unit (6)
A sliding plate (201) slidably supported on a side plate (62) of
), an L-shaped lever (202) rotatably supported by a pin (202a) on the casing (66), and a swinging end (202b) of the lever (202) and a pin (203). A push-down member (204) movably connected and slidably supported with respect to the casing (66), and a spring (205) that constantly biases the member (204) in the direction of arrow (11). Consists of etc.

Now, when the upper frame (101) of the copying machine main body is closed, the bent portion (201a) of the sliding plate (201) is formed in a part of the lower frame (102) or It comes into contact with a convex part (102a) fixedly installed on the holder and is lifted upward. (The state shown in Fig. 6.) In this state, the end (202C) of the L-shaped lever (202) that comes into contact with the step (201b) of the sliding member (201) is similarly lifted, and as a result, The mold lever (202) rotates clockwise, and the push-down member (204) is rotated by the spring (205).
) is being pulled against the urging force of Push-down member (204
The front end (204a) of the pin (204a) forms a slope-shaped cam surface, and the pin (204a) is connected to a spring (68) for pressing the blade member (61) into contact with the photoreceptor surface.
67), this cam surface (204a) is positioned so as to be able to come into contact with it. Therefore, when the upper frame (101) is opened, the cleaner unit (6) also rises,
The pushing up state of the sliding plate (201) by the convex portion (102a) of the frame (102) is released, and the spring (20
5) causes the push-down member (204,) to slide in the direction of arrow a, and the cam surface ('204a) moves forward while coming into contact with the upper part of the pin (67), thereby pushing down the pin (67). At this time,
The biasing force of the spring (20'5) is the spring (68)
Of course, it is set to be larger than the urging force of .

When the pin (67) is pushed down, the blade holding means (6
5)' rotates clockwise around the support shaft (64), and the blade portion H (6]) is separated from the surface of the photoreceptor drum (2).

Since the cleaner unit (6) and the photosensitive drum (2) can be attached and detached from the machine body when the upper frame (lot) is opened, the blade member (6) can be removed from the machine body in this state.
1) is away from the surface of the photoreceptor drum, the braided material (61) will not cause any inconvenience when the photoreceptor drum (2) is attached or removed.

In addition, the hook lever (210) shown in FIGS. 5 and 6.

(211) is for engaging and locking the cleaner unit (6) with the upper frame (101) of the main body, and the bearing boss portion (not shown) of the photosensitive drum (2) is connected to the unit side plate (211).
62), (63'), (62a), (6
3a), the receiver provided on the upper frame (101) connects the convex portion (62) on the unit (6) side to the member (not shown).
b), (63b: not shown), and then attach the hook levers (210), (211) to the frame (10
The hook lever (210), (211
) are always urged to rotate clockwise by a torsion spring (213), and are connected to each other by an operation plate (214) for unlocking. The lock is released using the hook lever (210) using the operation plate (214).
(211) counterclockwise to release the engagement with the pin (212).

FIG. 7 shows another embodiment of the blade approach and separation mechanism.

In this embodiment, the lever (211) swingably supported by the support shaft (2]0) is brought into contact with the upper part of the pin (67), and the bent portion of the lever (211) is moved by the torsion spring (212). (211a) is urged downward. On the other hand, a lever protruding from the side plate (62)
The swinging part (211b) of (211) is set so that it can come into contact with the convex part (102a) of the lower frame (102) of the main body, and when the upper and lower frames are closed, the lever (211b)
2] 1) is pushed up by this convex portion (1022).

When the upper frame (101) is lifted, the cleaner unit (6) also rises, thereby releasing the lever (2] 1 ) from being pushed up by the convex portion (102a). (211) is pushed down, thereby pushing down the pin (67) and separating the blade member (6]) from the surface of the photoreceptor drum (2).

As explained above, the present invention includes: a blade member that is pressed against the surface of the photoreceptor; a toner collecting casing that has an opening facing the photoreceptor surface to receive the toner scraped off by the blade member; This cleaning device for an electronic copying machine includes a coil spring for conveying toner, which is provided in the casing along the surface of the photoconductor and has a diameter larger than the width of the opening of the casing. It is possible to prevent disadvantages such as damage to the photoreceptor surface without sacrificing the advantages of using coil springs for conveying the photoreceptor.
Since the coil spring can be placed close to the photoreceptor surface, efficient toner conveyance can be achieved.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing the structure of the electrophotographic copying machine of the present invention, Fig. 2 (al is a sectional view showing the frame divided into upper and lower parts and its open state, Fig. 2 is a sectional view showing the torsion bar, Figure 3 is a diagram showing the frame lock and safety mechanism, Figure 4 (a) and Figure 4 tbl are side views of the main parts of Figure 3, and Figure 5
Figure ta+ is a sectional view showing the relationship between the cleaner unit and the photosensitive drum, Figure 5 tb+ is a diagram showing the setting conditions of the blade member, Figure 6 is a diagram showing the blade approach and separation mechanism, and Figure 7 is a diagram showing the setting conditions of the blade member.
The figure shows another example. 1... Copying machine, 2... Photosensitive drum. 6... Cleaner unit, 61... Blade member. 65... Blade holding means, 70... Toner conveying means. 71...Coil spring, 72...Coil casing Applicant Minolta Camera Co., Ltd.! Figure 12 (α) Ward Ward'/) Shu taste taste

Claims (1)

[Scope of Claims] 1. A toner collecting casing having a blade member that is pressed against the surface of the photoreceptor, and an opening facing the photoreceptor surface to receive the toner scraped off by the blade member; A cleaning device for an electronic copying machine, comprising: a coil spring for conveying toner, which is provided in the casing along the surface of the photoreceptor and has a diameter larger than the inside of the opening of the casing. 2. The cleaning device according to claim 1, further comprising a seal member provided along the opening of the casing and in contact with the surface of the photoreceptor so as to guide toner to the opening of the casing.