JPS5931704B2 - Paper conveyance prevention device - Google Patents

Description

[Detailed description of the invention] The present invention relates to a paper conveyance prevention device for an electronic copying machine.

In an electronic copying machine in which the document table moves in conjunction with the rotation of the photoreceptor drum and is equipped with a mechanism that operates in synchronization with the rotation of the photoreceptor drum, such as a paper feeding mechanism or paper transport mechanism. There is a two-rotation, one-copy type copying machine that uses a one-way operating cam, an operating lever, and a clutch to mechanically determine the timing for starting the operation of the above-mentioned mechanism.

First, an example of the above-mentioned copying machine will be explained with reference to FIGS. 1 and 2.

In the figure, reference numeral 1 indicates a photosensitive drum that rotates in the direction of the arrow. As shown in FIG. 2, on the shaft 2 of the photoreceptor drum 1, there is a pulley 3 for driving the document platen having the same circumference as the drum, and a one-way operating cam 4 (
A disk 5, on which a cam (hereinafter simply referred to as a cam) is fixed, is rotatably mounted integrally with the drum. Photosensitive drum 1
A document table T having a transparent document placing plate 6 is arranged above the document table.

On the document table T, both ends 8a and 8b of a driving wire 8, which is wound around the pulley 3 and wound around the intermediate pulley 9, are placed.
are fixed, and the document table 7 moves in conjunction with the photosensitive drum 1 via the same wire. Further, below the photosensitive drum 1, a paper feeding mechanism 10 and a paper conveying device 11 are respectively provided.

The paper feeding mechanism 10 includes a sheet cassette 13 containing paper 12.
It consists of a paper feed roller 15 that rotates in the direction of the arrow via a one-turn clutch 14, and a locking arm 16 that engages and disengages from the one-turn clutch 14. The locking arm 16 is fixed to a support shaft 17 that is rotatably supported by a stationary member (not shown). Further, a first operating lever 18 for operating the sheet feeding mechanism is fixedly mounted on the support shaft 17, with a free end 18a positioned on the rotation locus of the cam 4. The paper feed roller 15 is connected to a drive mechanism (not shown), and is connected to a one-turn clutch 14.
It is designed to rotate once and then stop. The paper conveyance device 11 includes a drive shaft 19 connected to a drive mechanism (not shown), a sprocket 20 fixed to this shaft, a sprocket 22 fixed to a driven shaft 21, and a chain 23 wrapped around these sprockets. and a sheet gripper 24 arranged orthogonally to the chain 23 and having both ends fixed to the chain.

The drive shaft 19 is connected to a drive mechanism via a one-turn clutch 25. The one-turn clutch 25 has a support shaft 2.
One arm end 26 of the two arm member 26 rotatably attached to 6c
a is engaged, cutting off the transmission of driving force from the drive mechanism to the drive shaft 19. The one-turn clutch 25 and the two-arm member 26 together with another mechanism (not shown) constitute a multi-turn clutch, and once the one-turn clutch 25 is released, the same clutch 25 rotates, for example, six times. Only then does the arm end 26a engage and lock with this. The pitch ratio between the sprocket and the chain is determined so that when the clutch 25 rotates six times, in other words, the sprocket 20 rotates six times, the chain 23 rotates once. At the other arm end 26b of the two-arm member 26, one end 29b of a connecting rod 29 is rotatably supported on a support shaft 27 and the other end 29a of which is connected to one end 28a of a second operating lever 28 for operating the paper transport mechanism. are connected. Second actuation lever 2
The other end 28b of the cam 8 is positioned within the rotation locus of the cam 4. Now, when a print button (not shown) is pressed, the photosensitive drum 1 rotates in the direction of the arrow, and its surface is subjected to electrophotographic processing by each copying unit (not shown).

While the document table 7 moves in the direction of the arrow in conjunction with the rotation of the photosensitive drum 1, the document image on the mounting plate 6 is irradiated onto the drum surface. As the photoreceptor drum 1 rotates, the disc 5
rotates, and the cam 4 fixed thereto moves the first actuating lever 1
8 and swings, the locking arm 16 swings clockwise, releasing the one-turn clutch 14. As a result, the paper feed roller 15 rotates once, and the paper 12 that is in contact with it is fed out as shown by a chain line 12A. The leading edge of the fed paper 12A is held by the waiting sheet gripper 2.
Sent to 4. Then, the cam 4 moves the second actuating lever 2
8 and swings clockwise, the two-arm member 26 swings counterclockwise to release the one-turn clutch 25. As a result, the chain 23 rotates in the direction indicated by the arrow, and the sheet gripper 24 grips and conveys the paper 12A. When the paper transport mechanism 11 starts operating, a toner image is formed on the surface of the photosensitive drum 1, and this toner image is transferred to the paper being transported.

After the transfer, the photosensitive drum 1 rotates one more time to clean its surface. That is, this copying machine is of a type in which the photosensitive drum rotates twice to obtain one copy. On the other hand, the document table 7 is moved forward during the first rotation of the drum 1, and during the second rotation, a control device (not shown) is activated to reverse the pulley 3, causing the document table 7 to move backward. When the photosensitive drum 1 finishes the transfer process and enters the cleaning process, the pulley 3, in other words, the disk 5, is reversed and the cam 4 engages again to swing the actuating levers 28, 18. As shown in FIG. 9, the cam 4 is designed to operate the actuating lever only during forward movement, and not to operate it during backward movement. That is, in FIG. 9, the cam 4 includes a cam plate 4a pivotally attached to a disk 5, and a shaft 4 attached to the cam plate 4a.
a spring 4c that gives a clockwise swinging habit around b;
It consists of a stopper 4d. During forward movement in the direction of arrow a, the free end of the cam plate 4a engages with the free end of the actuating lever to swing and operate it as shown by the chain line, but during backward movement as shown by arrow b. The cam 4A is the cam plate 4
Since the lever a swings counterclockwise against its habit and escapes, the operating lever cannot swing and is not operated. In the copying machine described above, the photosensitive drum 1 and the document table 7 are operationally integrated via the wire 8.

That is, when the photoreceptor drum 1 rotates, the document table 7 moves. In other words, when the document table 7 moves, the photoreceptor drum 1 moves.
will rotate. For example, when the main switch of the copying machine is turned off, when performing maintenance and inspection of the parts located below the document table, such as cleaning the optical system or replacing the light source lamp, in other words, when copying operations are not being performed. , when the document table 7 is moved in the direction of the arrow (see FIG. 1), the photosensitive drum 1 rotates in the direction of the arrow, and depending on the rotation angle, the cam 4 moves to the first or second position. 2 operating levers 18, 28
The levers collide with each other, causing these levers to swing. When the first operating lever 18 swings, the clutch 14 of the paper feed roller 15 is released, and when the main switch (not shown) is turned on, the print button is not pressed or the drum is rotated. , the paper feed roller 15 immediately starts operating,
The sheet cassette 13 sends out the soil paper 12. In the copying operation after pressing the print button, the cam 4
gives a regular paper feeding command to the first actuating lever 18, and there is a problem in that the feeding action is applied again to the paper that has already been sent out, or the next paper is sent out. The above problem occurs because the paper feed roller 15 is always in contact with the paper 12. Therefore, it is conceivable to adopt a configuration in which the paper feeding roller is separated from the paper when paper is not being fed, and the roller is brought into contact with the paper only during paper feeding, but this would complicate the configuration and cause problems such as those mentioned above. The problem remains as before. It is also conceivable to control the operation of the paper feed rollers using electrical processing to prevent the paper from being fed out inadvertently, but this poses the problem of increased costs. Also, the second
If the operating lever 28 is swung, the one-turn clutch 25 of the paper transport mechanism 11 will be released, and the rotation of the photosensitive drum 1 and the paper feeding operation of the paper feeding mechanism 10 will not be completely synchronized. Instead, it starts rotating at the same time as the main switch is turned on.

If the mechanism 11 operates in this way, the paper fed by the paper feed mechanism 10 will not be conveyed. As described above, when moving the document table without the need for conveying paper, the present invention mechanically operates the operating lever group of the mechanism that operates in synchronization with the photoreceptor drum, such as the paper feeding mechanism and the paper conveying mechanism. It is an object of the present invention to provide a paper conveyance prevention device that is controlled and placed in an inactive position.

Further, in the present invention, even if the main switch is in the on state, if the paper presence/absence detection means is emitting a paper out signal, the actuation lever group is placed in the inactive position. The present invention will be explained below with reference to illustrated embodiments.

In FIGS. 3 and 5, reference numeral 30 indicates a first operating lever for operating the paper feeding mechanism, and reference numeral 31 indicates a second operating lever for operating the paper transport mechanism. In addition, the above first,
The second actuating levers 30 and 31 have the same structure except for the lengths of the main bodies, so the structure will be explained using the first actuating lever 30 as a representative. As shown in FIG. 4, the first operating lever 30 includes a main body 33 swingably mounted on a support shaft 32, and a swing arm 35 swingably mounted on a free end of the main body with a hinge 34. , and a compressible spring 36 stretched between the swing arm and the main body 33.

The swinging arm 35 is moved by the elasticity of the spring 36.
It is given a swinging habit in the direction of arrow a1, in other words, a swinging habit in the direction of approaching the disk 38 on which the cam 37 is fixed. The free ends of the swing arms 35 of the first and second operating levers 30 and 31 are positioned on the rotation locus O of the cam 37, as shown in FIG. Next, a release lever 39 is arranged at an intermediate position between the first and second operating levers 30 and 31.

The release lever 39 is swingably supported by a support shaft 40, and the two arm ends 39a, 39b correspond to the swing arms 35 of the first and second actuating levers, respectively, with a disc 38. The other end 39c of the release lever 39 is connected to an operating rod 41a of a solenoid 41 that forms part of the control means. Further, a spring 42 is applied to the lever 39, giving the lever 39 the habit of swinging clockwise about a support shaft 40. The solenoid 41 is energized when a main switch (not shown) is turned on, and when the switch is turned off, the solenoid 41 is energized by the operating rod 41a.
is pulled out by the elasticity of the spring 42 as shown in FIG.

When the solenoid 41 is inactive, the release lever 39 is swung by the action of the spring 42, as shown in FIG.
The swinging arm 35 of the second operating lever is swung against its natural behavior.

That is, the swinging arm 35 shown in FIG. 5 is evacuated and held at a so-called inoperative position away from the rotation locus of the cam 37 fixedly planted on the disk 38.

Now, as shown in FIG. 5, when the solenoid 41 is inactive (in other words, when the main switch is off) and the document table (see FIG. 1) is manually moved, the document table driving pulley 43 is moved. The disk 38 rotates, but since the swing arms 35 of the first and second actuating levers are in the inactive position, even if the cam 37 rotates as shown by the chain line 37A. Even if the lever group is moved, the lever group will not be swung. Therefore, the paper feeding mechanism and the paper transporting mechanism can be maintained in an inoperative state, thereby eliminating the above-mentioned problems in the conventional apparatus. When the main switch is turned on, the solenoid 41 is energized, the operating rod 41a is attracted as shown in FIG. 6, and the static removal lever 39 is swung counterclockwise against the elasticity of the spring 42. let

Following the swinging of the release lever 39, the swinging arms 35 of the first and second operating levers swing in the direction of the arrow due to the elasticity of the spring 36, and their free ends are placed on the rotational trajectory of the cam 37. As a result, the lever group is placed in the operating position.
When the main switch is turned off in the state shown in FIG. 6, the solenoid 41 becomes inactive and the state shown in FIG. 5 is restored. In the above explanation, the control means is composed of the solenoid 41 and the main switch of the copying machine, and when the main switch is off and the document table is moved without conveying paper, the operating lever group of the paper feeding mechanism etc. The solenoid and main switch were linked to maintain the inactive position, but
A control means is configured by a solenoid and a paper presence/absence detection means,
The lever group can also be placed in the inactive position by the detection signal from the paper presence/absence detection means. Note that the paper presence/absence detection means includes one that directly detects paper fed by a paper feeder configuration or paper transport mechanism or paper in a sheet cassette;
Alternatively, there are various methods such as indirect detection based on whether or not a seat cassette is attached, and the detection means referred to in the present invention includes all of these. An example of the means for detecting the presence or absence of paper depending on whether or not a sheet cassette is attached will be explained with reference to FIGS. ing.

A seat cassette 4 is attached to the support shaft 45 as shown in FIG.
6 is attached to the support plate 44, the sheet placement plate 47
A push-up lever 48 that comes into contact with and raises this is fixed. This pushing up lever 48 is caused by the support shaft 45
The force is applied by a tensioning spring 50 hung on one end 49a of the set/detach lever 49, which is fixed to the holder. The other end 49b of the cassette attachment/detachment lever 49 extends from outside the copying machine to a position where it can be operated, and is adapted to be pushed down when the sheet cassette is attached or detached. Further, a lever 51 for pushing the switch is fixed to the shaft end of the support shaft 45. A paper presence/absence detection switch 52 is arranged at the tip of the lever 51. This switch 52 is composed of, for example, a normally closed switch, and the solenoid 41
(See Figures 5 and 6). and,
When the sheet cassette 46 is not installed or there is no paper in the power set, the lever 51 swings as shown by the chain line 51A in FIG. 8 to push the switch 52 and open the contact.

As the switch 52 opens, the solenoid 41 becomes non-conductive, and the release lever 39 swings to bring the swing arms 35 of the first and second operating levers into the inactive position, as shown in FIG. Rock and hold. Therefore, even if the document table is moved, the paper feeding mechanism etc. will not operate, thereby avoiding unnecessary troubles. As shown in FIG. 8, when the sheet cassette 46 containing paper 53 is installed, the lever 51 is positioned as shown by the solid line and the switch 52 is not activated.
Therefore, in this case, the first and second lever groups are
Placed in the operating position as shown. In the above, when a paper out signal is issued by the paper presence/absence detection means, the solenoid is activated (deactivated) to maintain the operating lever group of the paper feeding mechanism etc. in the inactive position. .

As explained above, when there is no need to transport paper, including when there is no paper, in other words, when no copying operation is being performed, the mechanism that operates in synchronization with the photoreceptor drum, such as the paper feed mechanism, operates. According to the present invention, in which the lever is mechanically held in the inactive position, even if the document table which is operatively integrated with the drum is moved, the paper feeding mechanism etc. will not be placed in the operating state, thereby preventing paper jams. No such problems occur at all.

Further, since the operating lever group is automatically placed in the inactive position in response to the paper out signal, inadvertent operation of the paper feeding mechanism, etc. is prevented.

[Brief explanation of drawings]

FIG. 1 is a front view showing an example of a copying machine to which the present invention is applied;
FIG. 2 is a side view of the main parts of the same as above, FIG. 3 is a front view showing one embodiment of the present invention, FIG. 4 is a perspective view showing an example of the operating lever, and FIGS. 5 and 6 are FIG. 7 is a side view showing the functions, FIG. 7 is a perspective view showing an example of the paper presence detection means, FIG. 8 is a front view showing the same function, and FIG. 9 is a front view explaining the function of the one-way operating cam. be. 1...Photosensitive drum, 6...Document stand,
10... Paper feeding mechanism, 11... Paper transport mechanism, 30, 31... Operating lever 39...
...Release lever, 41...Solenoid.

Claims (1)

[Claims] 1. A document table that moves in conjunction with the rotation of the photoreceptor drum;
A paper feeding mechanism and a paper transport mechanism operate in synchronization with the rotation of the photoreceptor drum, and the rotating photoreceptor drum is engaged with and swung, and the mechanism is engaged with and disengaged from the clutches included in each of the above-mentioned mechanisms. An electronic copying machine is provided with a group of actuating levers for controlling the operations of both mechanisms, and the actuating lever group and the photoreceptor drum are swingable between the group of actuating levers and the photoreceptor drum. and a control means for selectively swinging the release lever, and the control means swings the release lever so that the operating lever group and the A paper conveyance prevention device, characterized in that the paper feeding mechanism and the paper conveyance mechanism are maintained in an inactive position when the engagement with the photoreceptor drum is released. 2. The control means includes a solenoid that is turned on and off in conjunction with the on-off operation of the main switch of the copying machine, and when the solenoid is off, swings the release lever to close the operating lever group and the photoreceptor. The paper conveyance prevention device according to claim 1, characterized in that the device disengages from the paper conveyance prevention device. 3. The control means includes a solenoid that is turned off when the paper presence/absence detection means provided in the paper feeding mechanism or the paper conveyance mechanism emits a paper out signal, and when this solenoid is off, the release lever is turned off. 2. The paper conveyance prevention device according to claim 1, wherein the actuating lever group and the photoreceptor are disengaged by swinging.