JPH0323163A - Sheet refeed mechanism for image formation device - Google Patents

Abstract

PURPOSE:To simplify the constitution and control of a sheet re-feed mechanism by transmitting the torque of a roller to a sheet re-feed roller via the slip of the first and second members when the nip pressure of the sheet re-feed roller reaches the slip start force of a torque limiter. CONSTITUTION:When a sheet re-feed roller 12 is made to start rotation with a drive means, the first member 131 of a torque limiter 13 turns via a clutch 16 and a sheet re-feed axis 14. In addition, the second member 132 also starts to turn with the rotation of the member 131, thereby causing the turn of a support frame body 15 in a clockwise direction. Consequently, a sheet re-feed roller 11 is moved from the first state to the second state, and pressed to a sheet on a front guide board 2. In addition, the nip pressure of the sheet re-feed roller 11 is thereby made to reach a slip start force set in the torque limiter 13. Then, a slip is generated between the first and second members 131 and 132. In that state, the torque of the roller 12 is transmitted to the sheet re-feed roller 11 and sheet delivery starts. According to the aforesaid construction the constitution and control of a sheet re-feed mechanism can be simplified.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a paper refeeding mechanism provided in a copying machine or other image forming apparatus capable of double-sided copying or composite copying.

2. Description of the Related Art Copying machines capable of double-sided copying and double-sided copying are equipped with an intermediate storage section for temporarily storing sheets that have been subjected to single-sided copying or primary copying. The paper stored in the intermediate storage section is re-fed to the secondary paper feeding mechanism during double-sided copying or composite copying.

For this reason, this type of copying machine is equipped with a paper refeeding mechanism. Conventional paper refeed mechanisms usually include a paper refeed roller that feeds out the paper stored in the intermediate storage section, a paper refeed roller that transports the paper fed out by the paper refeed roller one by one, and a paper refeed roller that feeds the paper stored in the intermediate storage section. A solenoid that presses the paper feed roller against the paper in the intermediate storage section and lifts it off the paper, a clutch that turns on and off the paper refeed roller, and a clutch that prevents the paper stored in the intermediate storage section from being fed out. It is made up of stotsuba, etc.

Problems to be Solved by the Invention> Therefore, in order to operate the conventional paper refeeding mechanism, each component must be driven according to a predetermined sequence, and the control thereof is complicated. Another drawback is that there are many objects to be controlled, such as solenoids.

SUMMARY OF THE INVENTION In view of the above-mentioned drawbacks of the conventional apparatus, it is an object of the present invention to provide a paper refeeding mechanism for an image forming apparatus that is simple in structure and easy to control.

Means for Solving the Problems> The present invention is a mechanism for refeeding paper in an image forming apparatus, which comprises: a refeed roller that is pressed against the paper to be refed and feeds out the paper; A refeeding roller for conveying sheets one by one fed out by the refeeding roller, a driving means for rotating the refeeding roller, a rotatable first member and a second member, and a first member. A slip mechanism is provided which connects the second member and causes the two to slip when a force difference greater than a predetermined force occurs between the two members, and the first member rotates as the refeed roller rotates. a torque limiter, one end of which is fixed to a second member of the torque limiter, and the other end of which rotatably holds a paper refeed roller;
a roller displacement means that is displaced as the second member rotates and can switch the paper refeed roller between a first state in which it floats above the paper and a second state in which it is in pressure contact with the paper; A paper refeeding mechanism for an image forming apparatus is characterized in that it includes a rotational force transmitting means for transmitting the rotational force of a paper roller to a paper refeeding roller.

Further, the present invention provides that the paper refeeding mechanism of the image forming apparatus includes:
The apparatus further includes a stopper member for preventing the paper from being fed out, and a release means for releasing the stoppage of the stopper member in conjunction with the displacement of the roller displacement means to the second state. It is.

Function> When the drive means starts rotating the paper refeeding roller, the first member of the torque limiter rotates, and as the first member rotates, the second member also rotates. Therefore, the roller displacement means moves the paper refeed roller from the first state to the second state, and the paper refeed roller is pressed against the paper.

When the nib pressure of the paper refeed roller pressed against the paper reaches the slip start force set in the torque limiter, the first member and the second member are slipped.

In this state, the rotational force of the roller is transmitted to the paper refeeding roller, so that paper feeding begins.

Embodiment> FIG. 1 is a perspective view showing the configuration of a paper refeeding mechanism of a copying machine according to an embodiment of the present invention.

This paper refeeding mechanism is equipped with a feed roller 1, a guide plate 2 before width adjustment, a guide plate 3 after width adjustment, and a Baba stopper 4, which constitute an intermediate storage section.

The feed reroller 1 is configured to receive driving force from a feed reroller shaft 6 via a transmission gear 7, and the feed reroller 1 and the transmission gear 7 are attached to a feed reroller mounting plate 8. The feed roller mounting plate 8 is movable by a feed roller solenoid 9. When a single-sided copy or a primary copy of paper is stored in the intermediate storage section, the feed roller solenoid 9 is turned on, the feed roller 1 is positioned downward, and the leading edge of the conveyed paper is placed at the paper stopper 4. Feed the paper until it hits.

Next, the feed roller solenoid 9 is turned off and the feed roller 1 is moved upward. Then, in order to arrange the stored paper, a guide plate 2 before width adjustment and a guide plate 3 after width adjustment are installed.
performs width adjustment operation.

As described above, the paper refeed mechanism includes a paper refeed roller 11, a paper refeed roller 12, a torque limiter 13, and a paper refeed roller 11 as a mechanism for refeeding the paper stored in the intermediate storage section. A shaft 14, a support frame 15 and a clutch 16 are provided.

The paper refeeding roller 11 is lowered in the direction of arrow A1 and assigned to the paper to be refeeded, and is used to feed out the paper.

The paper refeed roller 12 is for conveying the sheets of paper fed out by the paper refeed roller 11 one by one, and is connected to the paper refeed shaft 14.
is fixed to.

The torque limiter 13 includes a rotatable first member 131 and a second member 132, and a slip mechanism (not shown) (for example, a limiter spring, a magnet, etc.) is provided between them. is provided. The slip mechanism causes the first member 131 and the second member 132 to slip when a force difference greater than a preset force occurs between them.

The torque limiter 13 including such a slip mechanism is
Since this is a well-known member, detailed explanation thereof will be omitted here. The first member 131 of the torque limiter 13 is fixed to the paper refeed shaft 14 and rotates together with the paper refeed shaft 14 . The second member 132 of the torque limiter 13 is attached to the support frame 1
It is fixed to 5. Note that the rotational force of the paper refeed roller 12 is transmitted to the paper refeed roller 11 by a gear mechanism 17, so that the paper refeed roller is rotated.

The feature of this embodiment is that by simply switching the clutch 16 on and off, the paper refeed roller 11 is lowered in the direction of the arrow A1 and brought into pressure contact with the paper, and the paper stop collar 4 is moved in the direction of the arrow A1.
Lower in two directions, refeed roller 11 and refeed roller 12
You can refeed the paper by rotating the paper refeed roller 11.
Also, the paper stopper 4 can be returned to its original state.

Figures 2 (A), (B), and (C) show the paper refeed roller 11 and the paper refeed roller 12 when the clutch 16 (see Figure 1) is turned on.
, is a schematic side view for explaining the operations of the torque limiter 13, the paper stopper 4, and the support frame 15. FIG.

Next, the operation of the paper refeeding mechanism of this embodiment will be explained with reference to FIGS. 1 and 2.

When the clutch 16 is turned on, the paper refeed shaft 14 starts rotating clockwise, and the first member 131 of the torque limiter 13 fixed to the paper refeed shaft 14 and the paper refeed roller 12 rotate. Further, the rotation of the first torque limiter member 131 is transmitted to the second torque limiter member 132 via the slip mechanism, and the second member 132 and the support frame 15 fixed thereto rotate in the direction of arrow A1.

As a result, the paper refeed roller 11 attached to the tip of the support frame 15 changes from the first state where it is floating above the paper as shown in FIG. 2(A) to the state where it is in contact with the paper as shown in FIG. 2(B). Displaced to 2 states. And more support.

When a force is applied to rotate the shredder 15 in the direction of arrow A1, the paper refeed roller 11 is brought into pressure contact with the paper, and its nib pressure increases.

Eventually, the nip pressure of the paper refeed roller 11 increases to the torque limiter 13.
is greater than the force set in the slip mechanism.

Then, a slip occurs between the first member 131 and the second member 132 of the torque limiter 13, and no more force is applied to the second member 132 and the support frame 15 to rotate them in the direction of arrow A1. The nip pressure of the paper feed roller 11 is kept constant.

When the support frame 15 rotates, the claw 151 provided at the end of the support frame 15 pushes the protrusion 19 of the support shaft 18 to which the paver stopper 4 is fixed in the direction of arrow A2, as shown in FIG. . As a result, the vapor stopper 4 is lowered in the direction of arrow A2, allowing the paper to be fed out.

On the other hand, the paper refeed shaft 14 continues to rotate, and the rotational force of the paper refeed roller 12 is transmitted to the paper refeed roller 11 via the gear mechanism 17.
, and the paper refeed roller 11 rotates. Therefore, the sheets stacked in the paper storage section are fed out sequentially from the top by the paper refeed roller 11, and double feeding is prevented by the pad 20.
The paper is conveyed one by one by the paper refeed roller 12.

In this embodiment, since the intermediate storage section is relatively deep, a feed reroller, a feed roller solenoid 9, etc. are provided. However, if the intermediate storage section that stores paper is relatively small, these feed reroller 1 and the feed roller solenoid 9 are provided. The feed coro solenoid 9 and the like may be omitted.

Furthermore, the page stopper 4 may be controlled independently by a solenoid or the like, without being linked to the displacement operation of the paper refeeding roller 11 as in this embodiment.

Note that when the clutch 16 is turned off, the support frame 1
It is preferable that a tension spring or the like is provided to constantly bias 5 in the direction opposite to the arrow A1.

In addition, the nib pressure of the paper refeed roller 11 is controlled by the torque limiter 1.
Since the slip mechanism No. 3 corresponds to the force difference that starts slipping, the nip pressure of the paper refeed roller 11 can be adjusted to the optimum pressure by appropriately changing the set value of the slip mechanism.

Furthermore, it is preferable that the paper refeed roller 12 is attached to the paper refeed shaft 14 via a one-way clutch. By doing so, there is no need to match the conveyance speed of the paper refeed roller 12 with the conveyance speed of the conveyance roller provided on the downstream side, and the conveyance speed of the downstream side conveyance roller can be made faster than the conveyance speed of the paper refeed roller 12. It is from. This is because if the paper refeed roller 12 is equipped with a one-way clutch, if the leading edge of the paper is pulled by the downstream conveyance roller while the paper refeed roller 12 is nipping the paper, the paper refeed roller 12 This is because the paper rotates idly with respect to the paper refeed shaft 14, and no more stress than necessary is applied to the paper.

Effects of the Invention> Since the present invention is configured as described above, the configuration and control of the paper refeeding mechanism for refeeding paper can be extremely simplified.

Further, by adjusting the torque limiter, the nip pressure of the paper feed roller can be changed, and the nip pressure for feeding out the paper to be re-fed can be optimized.

4. Of the drawings! 131jli Description FIG. 1 is a perspective view showing the configuration of a paper refeeding mechanism according to an embodiment of the present invention.

FIG. 2 is an illustrative side view for explaining the operation of essential parts of the sheet refeeding mechanism according to an embodiment of the present invention.

In the figure, 4...Paper stopper, 11...Refeed roller, 12...Refeed roller, 13...Torque limiter, 131...First member, 132...Second member, 14... Paper refeed shaft, 15... Support frame, 16...
・Clutch is shown.

Claims (1)

[Claims] 1. Refeeding paper in the image forming device A mechanism for The paper is pressed against the paper to be re-fed, and the paper is fed again. a refeed roller for ejecting the paper, One sheet of paper fed out by the refeed roller A refeed roller for conveying the paper in batches, Drive for rotating the paper refeed roller means and A rotatable first member and a rotatable second member. and connecting the first member and the second member, A force difference greater than the predetermined force occurs between the two. A slip machine that causes both to slip when The first member rotates the paper refeed roller. Torque that rotates as it rotates Krimitter and One end is fixed to the second member of the torque limiter. fixed, and the other end allows the refeed roller to rotate freely. holding the second member and rotating the second member. The re-feed roller is displaced as the paper moves. The first state is floating, and the first state is when the paper is pressed against the paper. A roller that can be switched to a second state. displacement means; The rotational force of the paper refeed roller is transferred to the paper refeed roller. a rotational force transmission means for transmitting; An image forming apparatus characterized by comprising: Paper refeed mechanism. 2. Reproduction of the image forming apparatus according to claim 1 The paper feeding mechanism further includes: Stretch to prevent paper from feeding out Upper member, The roller displacement means is displaced to the second state. In conjunction with this, the stopper member is and a release means for removing the blockage. This is a characteristic feature.