JPH034245A - Image forming device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention -1 The present invention supports a transfer material on a transfer material carrier that can freely come into contact with an image carrier such as a photosensitive drum and can freely rotate. The present invention relates to an image forming apparatus including a transfer device configured to transfer a toner image.

This is the sixth image forming apparatus equipped with this type of transfer device.
A color copying apparatus as shown in the figure is known.

In FIG. 6, 2 is a photosensitive drum as an image carrier;
The photosensitive drum 2 is uniformly charged by a primary charger 38, a latent image is formed by irradiating the photosensitive drum 2 with a light image 54 according to image information, and the latent image is developed with a developer by a developing device 40.
The latent image is made visible.

In the case of a color copying apparatus, the developing device 40 is a developing unit (40M) that separately stores four color developers: magenta developer, cyan developer, yellow developer, and black developer.
, 40C, 140Y, and 40B, and colors are reproduced by overlapping the above four color developers.

For this reason, a method has been proposed in which colors are visualized using four color developers on the photosensitive drum 2 and transferred to the transfer agent P, but the photosensitive drum 2 on which the toner image is formed is charged , the reproducibility of one color is poor because the development is carried out backwards.For these reasons, the transfer drum 1 as a transfer material carrier of the transfer device too is usually used as an intermediate carrier for supporting the transfer material P. , a method is adopted in which the toner image is repeatedly transferred onto the transfer material P each time a toner image is formed on the photosensitive drum 2.

The transfer drum 1 is rotated in synchronization with the photosensitive drum 2, and transfers the toner image on the photosensitive drum 2 onto a transfer material P supported on its circumferential surface. The transfer material P is supplied from the cassette 41 to the transfer drum 1. When the transfer is completed, the residual developer on the photosensitive drum 2 is removed by the cleaner 37, and the developing device 40 rotates in the direction of arrow G to replace the developing unit. development,
By repeating the transfer process four times, a color image is formed on the transfer material P on the transfer drum 1.

After the transfer has been completed, the transfer material P is separated from the transfer drum L by a static eliminator 43 and a separation claw 44, which neutralizes and releases the electrostatic attraction force on the transfer drum L, and is transported to a fixing device 46 by a transport device 45. After the image is fixed there, it is discharged to the outside of the copying rack.

Next, the transfer device 21100 and its surroundings will be explained.

As shown in FIG. 7, the photosensitive drum 2 has its rotating shaft 47.
the front and rear shaft support members 48 (only the front shaft support member is shown in the figure)
is rotatably supported in the direction of arrow H. The transfer drum 1 is rotatably supported around its central rotating shaft 6 by support plates 5.49 at the front and rear of the transfer drum 1, and is rotated in the direction of the arrow by a drive device (not shown). A swing shaft 4 is provided at one end of the drum support plate 5.49 on the photosensitive drum 2 side, and the swing shaft 4 is connected to the front and rear side plates 13.50 of the copying apparatus main body.
is engaged with the photosensitive drum 2 so as to be swingable in the normal direction of the photosensitive drum 2 (in the direction of arrow J). Also, the main body side plate 13.50
A release arm 14 having a tank moving roller 15 at its tip is attached to the release lever shaft 27 which is rotatably supported at both ends by portions 13a and 50a at a position opposite to the drum support plate 5.49. The release lever 3 is fixed to the front end of the release lever shaft 27 (on the front side of the decoration main body).

Each of the other ends of the drum support plate 5.49 has a cam follow surface 52 that contacts the tank moving roller 15 of the release arm 14, and a cam follow surface 52 that contacts when the transfer drum 1 is in the contact position t with respect to the photosensitive drum 2. A setting latch portion R1 and a contact release latch portion R2 are formed when the transfer drum l is in a position separated from the photosensitive drum 2, and the release arm 14 and the sliding roller are interlocked with the operation of the release lever 3. 15 swings to determine the position of the transfer drum 1, and the spring 51 at the lower end biases the drum support plate 5.49 downward, thereby realizing the abutting force of the transfer tram 1 against the photosensitive drum 2. There is.

A transfer sheet 58 that electrostatically attracts and supports the transfer material is wrapped between the front and rear drum flanges la and 1C of the transfer drum L, so that the front and rear drum flanges la and lc do not affect one image. is supported by a minimum number of supports 59. Therefore, there is a transfer sheet 5 inside the transfer drum 1.
The pressing sheet 57 in contact with the transfer drum 8 is tilted in the direction of rotation so that the rotation of the transfer drum 1 does not cause any disturbance, thereby maintaining the curvature of the transfer sheet 58. Also, inside the transfer drum l, there is a transfer charger 42 that moves the toner image on the photosensitive drum 2 to the transfer material on the transfer drum 1, and a charge eliminator 42 that removes and releases the electrostatic attraction force of the transfer material. 43 are included.

However, in the above-mentioned conventional example, since the transfer drum l adopts a configuration that minimizes the support column 59 as described above, the center of rotation is not located at the center of the rotation shaft 6, but is eccentric. When the contact force on the photosensitive drum 2 is released, the transfer drum 1 tries to stabilize and rotates on its own.

Therefore, when a paper jam (paper jam) occurs on the transfer drum 1, if the release lever 3 is operated to release the contact with the photosensitive drum 1, the rotation of the transfer drum 1 will cause the paper to become jammed. There were drawbacks such as deterioration and unprocessable results.

Therefore, an object of the present invention is to prevent paper jams from rotating on a transfer material carrier such as a transfer drum of a transfer device, and to easily dispose of the paper jams without deteriorating the situation. Image formation made possible! The aim is to provide A-placement.

The above object is achieved by the image forming apparatus of the present invention. To summarize, the present invention supports a transfer material on a transfer material carrier that can freely come into contact with an image carrier and can freely rotate, and transfers a toner image on the image carrier to the transfer material. When the transfer material carrier comes into contact with the image carrier and is released from contact with the image carrier, the transfer material carrier is brought into contact with the transfer material carrier and kept stationary, and the transfer material is transferred to the image carrier. Image forming characterized in that the transfer device is provided with a brake means for the transfer material carrier, which releases the contact with the transfer material carrier and enables rotation when the transfer material carrier comes into contact with the transfer material carrier. According to one aspect of the present invention, which is an apparatus, manual rotation means is provided for making it possible to manually rotate the transfer material carrier by coming into contact with the transfer material carrier when the transfer material carrier is stationary. According to one aspect, the brake means and the manual rotation means are integrally provided.

Embodiments of the present invention will now be described in detail with reference to the drawings.

1 to 3 show a transfer device in an embodiment of the image forming apparatus of the present invention.

The image forming apparatus of the present invention is characterized in that the transfer drum 1 serving as a transfer material carrier in the transfer device 21100 is provided with a brake means and a manual rotation means. Other configurations are
It is basically the same as the conventional image forming apparatus shown in FIGS. 6 to 7, and the same reference numerals in FIGS. 1 to 3 as those in FIGS. 6 to 7 indicate the same members.

In the drawings, Fig. 11(a) shows a state in which the transfer drum l is in contact with the photosensitive drum 2, and Fig. 1(b) shows a state in which the release lever 3 is operated in the direction of arrow A, and the transfer drum l is moved to the swing axis. This state is shown when the transfer drum 1 is moved in the direction of arrow B with rotation center 4 as the center of rotation, and this state is used when removing a jammed transfer material from the transfer drum 1 or when pulling the transfer drum 1 out of the apparatus.

Figure 2(a) shows an enlarged view of the brake means, and Figure 2(a) shows an enlarged view of the brake means.
b) shows a plan view of the brake means.

Furthermore, FIG. 3 shows means for manually rotating the transfer drum l.

The details of this embodiment will be explained below.

The transfer drum 1 is rotatably supported around a central rotating shaft 6 by a support plate 5 in front of the transfer drum 1 and a support plate (not shown) in the rear thereof. The drum front support plate 5 and the rear support plate hold a swing shaft 4, and when the swing shaft 4 engages with the centering plate 24, the relative position t between the transfer drum l and the photosensitive drum 2 is determined. It has become.

The release lever shaft 27, which is supported at both ends by the front side plate 13 and rear support plate (not shown) of the main body, has a release arm 14 having a sliding roller 15 at its tip, which is attached to the drum front support plate 5. The release levers 3 are attached at opposing positions, and the release lever 3 is fixed to the front end of the release lever shaft 27. Further, the other end of the release arm 14 is shaped to engage with the link shaft 17 of the link 16.

On the other hand, the drum front support plate 5 has a cam follow surface 52 with which the sliding roller 15 contacts, a contact setting latch portion R1 when the transfer drum 1 is in the contact position with the photosensitive drum 2, and a transfer drum l. Contact release latch i when it is in the position separated from the drum 2! lR2 is formed, and the release arm 14 and the sliding roller 1 are connected to the operation of the release lever 3.
5 swings, the transfer drum l swings around the swing shaft 4, and the transfer drum 1 is brought into contact with the photosensitive drum 2 at a position W (see Fig. 1).
a)) and the contact release position where it has separated from the photosensitive drum 2! !
(Fig. 1(b)).

In addition, at the bottom of the drum front support plate 5, there are
) is provided with braking means as shown in (). The braking means comprises rollers 7 with a high coefficient of friction (e.g. rubber rollers), which are connected by means of parallel pins 26 to a brake shaft 8 having a torque limiter 53 on the shaft. The end bearings (with detents) at both ends of the torque limiter 53 have a shaft 1 that swings around the brake swing shaft 11.
One ends of the pair of brake support plates 12 are engaged. An engagement shaft 9 that engages with the front side plate 13 of the main body is provided at the other end of the brake support plate 12 .

A contact spring 10 attached between the main body front side plate 13 and the brake support plate 12 allows the roller 7 to move toward the transfer drum 1,
In other words, the contact force is applied in the direction of arrow C. roller 7
, the slip torque (T2) of the torque limiter 53 (the torque below which it will not rotate) is set to be greater than the rotational torque (T2) of the transfer drum l (T
2>71), the rotation of the transfer drum 1 is prevented when the roller 7 contacts the flange la in front of the transfer drum l.

Furthermore, a manual rotation means for the transfer drum 1 as shown in FIG. 3 is provided on the upper part of the front side plate 5 of the drum. It has a swinging arm 20 that moves. Swing arm 2
At one end of 0, there is a rotating gear 22 that engages with the transfer drum lb.
is attached to the rotating shaft 23, and the knob shaft 2
It is rotatable via a knob gear 55 at the other end of the 5. A shaft 19 is provided at the other end of the swing arm 20, and the shaft 19 engages with the link 16. The link shaft 17 at the lower end of the link 16 is fitted into an elongated hole 13c formed in the front side plate 13 of the main body, and is connected to the release arm 14 described above.
is engaged. A spring 18 is coupled between the link 16 and the link shaft 17 to pull the link shaft 17 upward.

In this configuration, when removing the jammed transfer material from the transfer drum 1, the following procedure may be performed.

That is, in order to separate the transfer drum 1 from the photosensitive drum 2, the release lever 3 is operated in the direction of arrow A, as shown in FIGS.

When the release lever shaft 27 is rotated by operating the release lever 3, the release arm 14 swings, and the JM moving roller 1 at the tip of the release arm 14 swings.
When the drum front support plate 5 slides on the cam follower surface 52 and is positioned at the contact release latch portion R2, the drum front support plate 5 moves around the swing shaft 4.
swings in the direction of arrow B, and the contact of the transfer drum l with the photosensitive drum 2 is released.

On the other hand, since the engaging shaft 9 of the brake means is engaged with the main body front side plate 13 in the contact state, the roller 7 is
It is in a state away from the front 7 lunge la. As the drum front support plate 5 swings as described above, the engagement shaft 9 separates from the main body front side plate 13. Therefore, the contact spring 10
The reaction force causes the roller 7 to move toward the front flange la of the transfer drum l.
The rotation of the transfer drum l due to the eccentricity of the rotation center is prevented. Therefore, the transfer material jammed on the transfer drum 1 can be removed without aggravating the jam.

On the other hand, in order to push down the link shaft 17 of the release arm 14, the swinging arm 20 of one manual rotation means swings via the link 16, and the swinging gear 22 at the other end is connected to the transfer drum gear lb.
As a result, by manually rotating the knob shaft 25 using the knob 21, the transfer drum l, which is stationary by the brake means, can be arbitrarily rotated. Therefore, when removing the transfer material stuck on the transfer drum l, it becomes easy to remove it.

Conversely, when the release lever 3 is operated in the direction opposite to the direction of the arrow in order to bring the transfer drum l into contact with the photosensitive drum 2, the link shaft 17, which is no longer regulated by the release arm 14, is pushed upward by the reaction force of the spring 18. being pushed back. As a result, link 16
．． The rotating gear 22 is separated from the transfer drum gear lb via the swinging arm 2o. Further, when the drum front support plate 5 swings at M9 due to the movement of the release lever 3, the engagement shaft 9 of the brake means is pressed against the main body front side plate 13. As a result, the brake support plate 12 swings about the brake swing shaft 11, and the roller 7 separates from the flange la of the transfer drum l.

As described above, according to this embodiment, the rotation of the transfer drum 1 can be prevented by the braking means by simply operating the release lever 3, and the stationary transfer drum 1 can be manually rotated by the manual rotation means. be able to. Furthermore, by providing a brake means within the unit of the transfer device 100, rotation of the transfer drum 1 can be prevented even when the unit is removed from the device main body as a single unit.

Next, other embodiments of the present invention will be described.

4 and 5 show a transfer device in another embodiment of the image forming apparatus of the present invention.This embodiment is characterized in that the manual rotation means is integrally provided with the function of a brake means.

In the figures, FIG. 4(a) shows a state in which the transfer drum 1 is in contact with the photosensitive drum 2, and FIG. 4(b) shows a state in which the release lever 3 is operated in the direction of arrow A to swing the transfer drum 1. In this FIG. 4(b), which shows a state in which the centering plate 24 shown in FIG.
is removed. FIG. 5 is a detailed view of the manual rotation means which has the function of a brake means, FIG. 5(a) is an enlarged view thereof, FIG. 5(b) is a horizontal sectional view thereof, and FIG.
c) is an explanatory diagram showing the direction of rotation.

The details of this embodiment will be explained below.

The transfer drum 1 has a central rotary wheel 6 rotatably supported by a support plate 5 in front of the transfer drum 1 and a support plate (not shown) in the rear thereof. The drum front support plate 5 and the rear support plate hold a swing shaft 4, and when the swing shaft 4 engages with a centering plate 24, the relative positions of the transfer drum 1 and the photosensitive drum 2 are determined.

Further, a release arm 14 having an active roller 15 at its tip is attached to a release lever shaft 27 supported at both ends by a front side plate 13 and a rear support plate (not shown) of the device main body.
It is attached at a position opposite to the release lever shaft 2.
A release lever 3 is fixed to the front end of 7. Further, the other end of the release arm 14 is shaped to engage with the link shaft 17 of the link 16.

On the other hand, in front of the drum, the support plate 5 has a cam follower surface 52 in contact with the sliding roller 15, a contact setting latch portion R1 when the transfer drum l is in the contact position with the photosensitive drum 2, and a transfer drum l. A latch portion R2 is formed for releasing the contact when the photosensitive drum 2 is in a position separated from the photosensitive drum 2, and the release arm 14 and the $g moving roller 1 are connected to each other in conjunction with the operation of the release lever 3.
5 swings, the transfer drum l swings around the swing shaft 4, and the transfer drum l is brought into contact with the photosensitive drum 2 (see Fig. 4).
a)) and the contact released position 1 (
Position it as shown in FIG. 4(b)).

The centering plate 24 is also provided with a manual rotation means for the transfer drum l as shown in FIGS. 5(+L) to (c). The fixed support plate 34 is swingably attached to the centering plate 24 via the swing support plate 33 with stepped screws 36. A rotating gear 22 that engages with the gear 1b of the drum 1 to impart rotation thereto is attached by a parallel pin 26 so as to rotate together with the rotating shaft 29. Furthermore, drum gear lb
In order to guarantee the distance between the gear pitches of the rotating gear 22, a protruding roller 28 is attached to the rotating wheel 29 that abuts the drum 7 lange ib.A knob 21 is attached to the other end of the rotating shaft 29. It will be done.

A rotation shaft 2 is provided between the swing support plate 33 and the fixed support plate 34.
There are 30 one-way bearings with built-in one-way bearings and anti-rotation shafts, as shown in Figure 5 (C).
As shown, the knob 21 functions so that it does not rotate clockwise but can freely rotate counterclockwise. Further, a rotation bearing 32 is added to the fixed support plate 34 so as to rotate integrally with the rotation shaft 29 via a parallel pin 26.

A torque spring 31 that provides one rotation resistance is fitted between the one-way bearing 30 and the rotation bearing 32 on the rotation shaft 29. That is, due to the reaction force of the torque spring 31, a frictional force generated at the contact surface between the swing support plate 33 and the one-way bearing 30, and also at the contact surface between the fixed support plate 34 and the rotation bearing 32, generates a rotational resistance torque (T3). let

The rotating means is pulled counterclockwise by a spring 35 attached between the swing support plate 33 and the centering member 24. The centering plate 24 is provided with an opening 56 that prevents the drum gear lb from interlocking with the rotating gear 22 of the rotating means when the transfer drum 1 contacts the photosensitive drum 2.

In the above configuration, when the release lever 3 is operated to release the contact of the transfer drum l with the photosensitive drum 2, the gear tb of the transfer drum 1 and the opening gear 22 are engaged, and the eccentricity of the rotation center of the transfer drum l is caused. Regulates rotation by That is, the fifth
When the transfer drum 1 attempts to rotate in the direction indicated by the arrow in FIG. 3(a), the one-way bearing 30 restricts the rotation, and the transfer drum 1 does not rotate.

Also, when the transfer drum l tries to rotate in the direction of arrow E,
There is no regulation for one-way bearing 30, but torque spring 31
The rotational resistance torque (T3) generated by
With this setting, the transfer drum l is braked and stops without rotating. However, when the knob 21 is operated, the transfer drum 1 rotates only in the direction of the arrow E due to the function of the one-way bearing 30, and the pressing sheet inside the transfer drum 1 is not affected.

When the release lever 3 is operated to bring the transfer drum 1 into contact with the photosensitive drum 2, the rotation gear 22 is disengaged from the drum gear lb, and is released from the restriction of the rotation means.

As described above, according to this embodiment, the mechanism can be simplified by providing the centering plate 24 with a rotation means that integrally has the function of a brake means.

As explained above, in the image forming apparatus δ of the present invention, when the transfer material carrier such as a transfer drum is released from contact with the image carrier such as a photosensitive drum, the transfer material carrier is removed. To the body! Since the transfer device is provided with a brake means for the transfer material carrier, which contacts the image carrier in a manner similar to the image carrier, and releases the contact with the transfer material carrier in conjunction with the transfer material carrier when the transfer material carrier comes into contact with the image carrier. Even if a paper jam or the like occurs on the transfer material carrier, it is possible to prevent deterioration in handling of the paper jam or the like due to the rotation of the transfer material carrier and prevent accidents.

In addition, by further providing a manual rotation means to the transfer device, 4
Processes such as removing jammed transfer material can be made easier, and can be easily simplified by integrating the functions of the brake means and the sliding rotation means.

[Brief explanation of the drawing]

FIGS. 1(a) and 1(b) are side views showing a transfer device in an embodiment of the image forming apparatus of the present invention, and show states in which the transfer drum is brought into contact with the photosensitive drum and when the contact is released, respectively. FIGS. 2(a) and 2(b) are a side view and a plan view, respectively, showing brake means provided in the transfer device shown in FIGS. 1(a) and (b). FIG. 3 is a plan view showing a manual rotation mechanism provided in the transfer device shown in FIGS. 1(a) and 1(b). FIGS. 4(a) and 4(b) show a transfer device in another embodiment of the image forming apparatus of the present invention, and show the states of contact and release of the transfer drum against the photosensitive drum, respectively. FIGS. 5(a), (b), and (c) are a side view, an above-water sectional view, and an explanation of the operation of the manual rotation means provided in the transfer device shown in FIGS. 4(a) and (b), respectively. It is a diagram. FIG. 6 is a configuration diagram showing a conventional image forming apparatus. 7 is a perspective view showing the vicinity of a transfer device provided in the image forming apparatus shown in FIG. 6. FIG. 1: Transfer drum 2: Photosensitive drum 3: Release lever 7: Roller 22: Rotating gear 30: One-way bearing is shown in Figure (a) Lock Figure 6

Claims (1)

[Scope of Claims] 1) A transfer material is supported on a transfer material carrier that can freely come into contact with the image carrier and can freely rotate, so that the toner image on the image carrier is transferred to the transfer material. In an image forming apparatus equipped with a transfer device, when the transfer material carrier that has been in contact with the image carrier is released from contact, the transfer material carrier is brought into contact with the transfer material carrier and kept stationary, and the An image forming apparatus characterized in that the transfer device is provided with a brake means for the transfer material carrier, which releases the transfer material carrier from contact with the transfer material carrier to enable rotation when the transfer material carrier comes into contact with the transfer material carrier. . 2) manual rotation means that comes into contact with the transfer material carrier and enables manual rotation of the transfer material carrier when the transfer material carrier is stationary;
The image forming apparatus according to claim 1, wherein the image forming apparatus is provided in the transfer device. 3) The image forming apparatus according to claim 2, wherein the brake means and the manual rotation means are integrated.