JPH0215455B2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field The present invention relates to a copying machine in which a paper feed cassette for storing a bundle of paper is inserted into a copying machine, etc., and the paper is fed one by one by a paper feeding means provided in the copying machine, etc. Related to paper feeding devices such as machines.

Prior Art Paper feeding devices for transfer paper in electrophotographic copying machines, printers, facsimile machines, etc. use paper feeding cassettes that are pivoted on a fulcrum at the bottom of the container and have a bottom plate on which a stack of paper is placed. It is inserted into a copying machine, etc., and the above-mentioned bottom plate is rotated upward by a push-up member provided on the copying machine, etc., so that the top surface of the stack of sheets is pressed into contact with the paper feed roller of the copying machine, etc., and the sheets are loaded one by one from the top. Paper feeding devices that feed paper are widely used. However, in conventional paper feeding devices of this type, the bottom plate is generally pressurized by pressing a push-up member against the bottom plate using a tension spring, and when the cassette is attached or detached, the pressure is applied by a switching lever or by pressing the side of the cassette. It was necessary to temporarily separate the pressure member from the bottom plate by using a cam provided at the bottom plate against the force of the spring. For this reason, models that release the pressing force using a switching lever transfer the force to operating the lever, which not only takes time, but also causes damage to the cassette or the main body of the copying machine, etc., if the user forgets to release the release button and tries to attach or remove the cassette. However, even with a cam provided on the side of the cassette, a considerable amount of operating force is required to attach and detach the cassette, resulting in poor operability. In addition, paper feeding pressure is generated by the load of the above-mentioned tension spring being applied between the paper and the paper feeding means, but this pressure changes depending on the displacement of the spring and the paper's own weight, so the paper stack on the bottom plate The disadvantage is that stable paper feeding pressure cannot be obtained depending on the amount of paper and paper size.

Purpose This invention solves the above-mentioned drawbacks of paper feeding devices such as copying machines that use conventional paper feeding cassettes. It is an object of the present invention to provide a paper feeding device which can be maintained, and which can smoothly and reliably perform the bottom plate driving operation and the mounting of a cassette.

Configuration The present invention will be described in detail below based on embodiments shown in the drawings.

In the embodiment shown in FIGS. 1 and 2, the bottom of the cassette container 1 has a bottom plate 2 on which a stack of sheets P is placed.
is a slit 1- provided at one point on the bottom of the container 1.
A retaining member 3 is attached to the retaining member 5 so as to be rotatably inserted into the retaining member 5 and not to come off. On the other hand, a friction pad 4 is attached to a recessed portion in the center of the front end (left end in the figure) of the bottom plate 2. A lifter 51 that rotates together with a shaft 50 is provided in the cassette insertion portion of the cassette-attached body of a copying machine (hereinafter referred to as the copying machine), and the shaft 50 rotates counterclockwise. As a result, the lifter 51 rotates through the relief holes 1-4 provided in the bottom and front wall of the cassette container 1, pushes up the bottom plate 2, and feeds the top surface of the stack of sheets P placed thereon. It is pressed against the paper roller 100.
The paper feed roller 100 rotates in the direction of the arrow in response to the paper feed signal to feed out the paper. Paper feed roller 10
0 is pivotally supported on the tip of a lever 110 that is pivotally supported on a shaft O, and is prevented from descending below a certain level by a stopper (not shown). On the axis O, there is a roller 200 that rotates in synchronization with the paper feed roller 100 in the same direction.
The separation roller pair 200 is constituted by a roller 200b, which is rotatable only in the direction of pushing the paper back toward the cassette. Lever 1
10 is provided with a protrusion 110a, and a sensor S1 is provided which is activated by the protrusion 110a when the paper feed roller 100 is pushed up to a height suitable for predetermined paper feeding.

A cover 5 is provided on the upper surface of the container except for a part of the front part. A hinge pin 6 is implanted in a hinge member 7 provided on both sides of the front end of the container, and a hole 1 provided in the side wall of the container is attached.
-3 is pivotally connected to the container 1 by fitting into the container 1;
It can be opened and closed by holding the rear end and flipping it up in the direction of the arrow. The cover 5 can be held in its open position and closed position by a click stop mechanism (not shown). A roller 8 is provided on the side surface of the end of the hinge member 7. The roller 8 is engaged with a guide pin installed inside the side plate of the container 1 through an elongated hole, and is movable in the front-rear direction within a certain range. It engages with the rear end of the slider 9, which is biased rearward. A cam 11 is attached to the front end of the slider 9, which is formed by bending a leaf spring and is elastically deformed by external force.

Near the front ends of both sides of the container 1, protrusions 1-1 extending in the front-back direction are provided, and a recess 1-2 is provided at the lower edge.
These are connected to the groove 30-1 of the guide block 30 fixed to the cassette mounting part of the copying machine, and the guide pin 3.
0-2, the cassette is set in place. When removing the cassette from the copier, lift the rear end of the cassette and remove it from the recess 1-
2 is removed from the guide pin 30-2 of the guide block, and the protrusion 1-1 moves along the groove 30-1 of the block 30. When the cassette is attached or removed, the lifter 51 is lowered as will be described later, so it can be removed without any trouble.

One end of the shaft 50 of the lifter 51 is swingably supported around a point on one side plate of the copying machine (not shown), and the other end passes through a long hole provided in the other side plate. It is swingable and rotatable around its own axis. As shown in FIG. 2, a sector gear 52 is fixed to the end of the shaft 50 that passes through the elongated hole. On the side plate of the copying machine are a drive motor 81, a worm 82 attached to its shaft, a worm gear 83 that meshes with this, a gear 84 that rotates together with this, a gear 85 that meshes with this,
A drive unit 80 is attached which rotates together with this and includes a gear 86 that can mesh with the sector gear 52.

Lifter 51 attachment part of shaft 50 and sector gear 5
2 is held between both legs of a bifurcated rocking lever 60 that is pivotally supported by a shaft 62. An arm 60a extending parallel to the shaft 50 from the side of the lever 60 is attached with a spring 64 that urges the lever 60 clockwise around the shaft 62, and a roller 61 is attached to the tip of the arm 60a. There is. Kokoro 6
1 engages with the upper surface of the cam 11 attached to the front end of the slider 9 of the inserted cassette 1, and when the cover 5 of the cassette is closed and the slider 9 is in the advanced position, the roller 61 is pushed against the cam 11. When raised, the lever 60 rotates counterclockwise by a certain angle against the spring 64, moving one end of the shaft 50 held between the legs of the lever 60 in a direction toward the cassette,
The sector gear 52 and the gear 86 of the drive unit are brought into mesh with each other. A plate spring tongue piece 63 is attached to the front edge of the lever 60 in the opposite direction to the arm 60a so as to face a micro switch 70 fixed to the copying machine. When the lever 60 is rotated counterclockwise as described above, the tongue piece 63 operates the micro switch 70 to start the motor 81 before the sector gear 52 engages with the gear 86. Furthermore, the lever 60 rotates and the sector gear 5
2 and the gear 86, the tongue piece 63 is deformed due to its elasticity, and both the tongue piece itself and the switch 70 are prevented from being damaged.

Further, a pair of a lamp L and a sensor _S2 is provided at a position where the optical path can pass through a hole provided in the inner bottom plate of the cassette 1, so as to detect the presence or absence of paper on the bottom plate.

Since this device is constructed as described above, when the cover 5 is opened and paper is placed on the bottom plate of the cassette 1, and the cover 5 is closed, the slider 9 is pushed at its rear end by the roller 8 and resists the spring 10. The roller 61 is pushed up by the spring cam 11 attached to the tip slightly protruding from the notch 1-6 of the container, and the lever 60 is rotated counterclockwise against the spring 64. Then, the tongue piece 61 first operates the micro switch 70, and when the main switch of the main body of the apparatus such as a copying machine is on, the motor 81 starts rotating. As the lever 60 continues to rotate, the sector gear 52 and the gear 85 begin to mesh. At this time, the motor 81 is already in a rotating state, so even if the tooth tips of the sector gear 52 and gear 85 touch each other, they will immediately become engaged, and at that point the lifter 5
1 starts rotating together with the shaft 50, raising the bottom plate 2. When the upper surface of the paper P placed on the bottom plate 2 hits the paper feed roller 100 and pushes it further up to a certain height, the protrusion 110a of the lever 110 activates the sensor _S1 and stops the motor 81. . Even when the motor 81 stops, the worm 82 and the worm gear 83 hold the bottom plate in that position. When the height of the stack of sheets decreases due to repeated copying, the protruding piece 110a of the lever 110 comes off the sensor _S1 , and the motor 81 rotates again in response to the signal, raising the paper feed roller 100 to a predetermined position. By repeating this, the top surface of the paper and paper feed roller 1
00 is always kept within a predetermined range, and the paper feeding pressure is always kept unchanged because it is determined by the weight of the paper feeding roller 100 and the lever.

When the paper continues to be fed and there is no more paper on the bottom plate 2, it is detected by the lamp L and the sensor _S2 , and the motor 81
and displays the paper end.

When the cover 5 of the cassette 1 is opened, the roller 8 moves backward, the slider 9 is pulled backward by the spring 10, the cam 11 and the roller 61 are disengaged, and the lever 60 is rotated clockwise by the spring 64. First, the meshing between the sector gear and the gear 86 is disengaged, and the lifter 51 and the shaft 50 lift the cassette 1 due to its own weight.
Fall to the bottom of the. Then, the tongue piece 63 is removed from the micro switch 70. As a result, even if the motor 81 is rotating (if the cover is opened with paper on the bottom plate 2), the power to the motor 81 is cut off and the motor 81 stops. As a result, paper can be easily replenished from under the cover 5, which is wide open at the rear, onto the bottom plate 2, which is separated from the paper feed roller 100 by a large distance.

When the cassette is pulled out of the copying machine in order to replace the cassette, the cam 11 at the tip of the slider 9 and the roller 61 of the lever 60 are disengaged, so the lifter 51 descends and the cassette can be pulled out and inserted. It will not affect the wear.

Next, with the power of the device body turned off, insert the cassette 1 into the device body or close the cassette top lid 5. This causes the slider 9 to move forward and the cam 11 to move toward the roller 6.
1, the drive motor 81 does not rotate even if the micro switch 70 is pressed, so the gear 8
If the tooth tips of sector gear 6 and sector gear 52 are in contact with each other, the teeth will not mesh. If you forcefully insert the cassette 1 without the teeth meshing properly, or close the top cover 5.
If an attempt is made to further close the cam 11 and the roller 61, if there is no relief in the engagement between the cam 11 and the roller 61, the parts will be deformed and damaged.

However, in the device of this embodiment, the cam 11 is made by bending a leaf spring into a predetermined cam shape.
Even if the cassette 1 is inserted or the top cover 5 is closed with the power off, if a force exceeding a predetermined force is applied to the cam 11, the cam will easily deform and escape, thereby preventing deformation and damage to the parts. can be avoided.

3 and 4 are diagrams showing another method of elastically engaging the cam with the roller, and the slider 9-1
A cam 11-1 made as a rigid member is installed at the front end of the
is rotatably supported by pin 9-2, and pin 9-2
A compression spring 9-3 provides clockwise rotational behavior between the protrusion of the slider 9-1 extending further forward, and the pin 9-1 on the upper edge of the cam 11
A stopper 11-1' formed rearward of slider 9-1 contacts the upper edge of slider 9-1 to restrict clockwise rotation.

Therefore, as described above, when the sector gear 52 and the gear 86 do not mesh, the slider 9-1
When the cam 11-1 engages with the roller 61, the lever 60 supporting the roller 61 does not rotate, so the roller 61 is not pushed up.
Cam 11-1 and roller 6 in a state of escape against -3
1 elastically engages with each other, thereby avoiding strain on each component.

In yet another embodiment shown in FIGS. 5 and 6,
There is no difference from the conventional method in that a bottom plate 501 having a friction pad 503 at the tip is rotatably attached to the bottom of the paper feed cassette 500 by a retaining member 502.

At the front end of this cassette 500 is an actuating piece 504 formed by bending a plate spring so that its cross section forms a J-shape.
is installed. This actuating piece 504 is adapted to directly push the shaft 600 by pushing a roller 602 attached to one end of the shaft 600 that fixes the bottom plate push-up member 601 when the cassette 500 is inserted. Furthermore, axis 6
A sector gear 603 is integrally fixed to 00, and meshes with a drive gear 700 driven by a motor (not shown). The shaft 600 is supported at one end (the end on the far right side in FIG. 6) so as to be able to swing around a point on a side plate (not shown) and to be able to rotate around its own axis. The end portion provided with is pivotally supported by a bearing 607 that moves along an elongated hole 650 provided in a side plate of the main body (not shown). The bearing 607 is pushed to the right in the figure by a compression coil spring 605.

Therefore, when the cassette 500 is not inserted in the predetermined position, the shaft 600 is pushed by the spring 605 and comes into contact with the right end of the elongated hole 650, and the sector gear 603 and the drive gear 700 are not engaged. do not have. When the cassette 500 is inserted into the main body of the device, the actuating piece 504 pushes the roller 602 and the sector gear 603
is pressed by the drive gear 700, and if the main switch of the device is on, the drive gear 700 rotates and meshes with these, and if the main switch is off and the teeth of both gears 600 and 700 Actuating piece 5 even when the first comrade hits and there is no meshing.
04 is elastically deformed, and the cassette can be reliably installed without putting any strain on the parts.

Effects As described above, according to the present invention, the paper feed cassette can be easily and reliably installed in a predetermined position without straining each member, regardless of whether the power switch of the main body of the device is turned on or off. Deformation and damage to parts can be prevented.

[Brief explanation of drawings]

Fig. 1 is a vertical sectional view showing an embodiment of the present invention, Fig. 2
The figure is an exploded perspective view, FIG. 3 is a side view showing another embodiment of the actuating piece that connects and disconnects the power transmission means to the shaft for rotating the cassette bottom plate, FIG. 4 is an exploded perspective view, and FIG. FIG. 6 is a longitudinal sectional view showing still another embodiment, and FIG. 6 is a perspective view thereof. 1,500...cassette, 2,501...bottom plate, 9-3...spring, 11,11-1,504...
... Actuation piece, 50,600 ... Bottom plate rotation shaft, 51,
601... Lifter (bottom plate push-up member), 52, 8
2-86,700,603...Power transmission means, 8
1... Drive source, 100... Paper feeding means, P... Sheet of paper.

Claims (1)

[Scope of Claims] 1. A paper feed cassette having a bottom plate pivotably supported on the bottom of the container so that it can rise and fall is inserted into the main body of the device with a stack of paper placed on the bottom plate, and the bottom plate circuit provided in the device is inserted into the main body of the device. In the paper feeding device that feeds sheets one sheet at a time from the top by pushing up the bottom plate with a bottom plate push-up member fixed to the moving shaft and pressing the top surface of the stack of sheets against the paper feeding member, the bottom plate rotating shaft described above is provided. a drive source for driving the drive source, a gear train for transmitting power from the drive source to a shaft for rotating the bottom plate, and for displacing the shaft for rotating the bottom plate to mesh a specific pair of adjacent gears in the gear train; A power transmission means that can be connected for power transmission by being hung or unhooked; and a power transmission means that is displaceable with respect to the main body of the device and that directly or indirectly engages and disengages from an actuating piece provided on the paper feed cassette, and that is connected to the bottom plate. engaged with a rotating shaft and displaced by engagement and disengagement of the actuating piece in response to movement when the paper feed cassette is attached to and detached from the main body of the device;
It has a bottom plate rotation shaft displacement mechanism constituted by a member that displaces the bottom plate rotation shaft, and the member constituting the bottom plate rotation shaft displacement mechanism and the actuating piece of the paper feed cassette are elastically engaged with each other. A paper feeding device characterized in that: