JPH04125231A - Paper feed device - Google Patents

Abstract

PURPOSE:To reduce the cost of a paper feed device by providing a drive source for driving an elevating means through the intermediary of a power transmission means, to the elevating means for a loading plate, and by providing a torque limiter for cutting off power transmission when the loading bed is lowered down to a paper unfeed position, to the power transmission means. CONSTITUTION:The bottom plate of a cassette on which sheets are loaded, is elevated in association with the turning of a lever 81 which is secured to a drive shaft 82 that is coupled to a motor 85 through the intermediary of a drive transmission means 84 composed of a belt 8, a pulley 87, gears 88, 89, 90, 91, 92 and a sector gear 93. A spring clutch 94 as a torque limiter is disposed between the gears 88, 89. Accordingly, the motor 85 is reversed so that lever 81 is turned in a direction in which the bottom plate is lowered, resulting in that it comes to abut against a base 96, and accordingly, the clutch 94 is slackened so as to slip, causing the lever 81 is held in a rest condition. After a predetermined time elapses, the motor 35 is stopped. Accordingly, it is possible to eliminate the necessity of a lower limit detection sensor, thereby it is possible to reduce the cost of the paper feed device.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to a paper feeding device that is provided in, for example, an electronic copying machine and supplies paper.

(Prior Art) This type of paper feeding device includes a paper feeding cassette (storage section) for storing paper, and the paper is fed from this paper feeding cassette.

The above-mentioned paper is placed on the bottom plate (placing plate) in the paper feed cassette, and this bottom plate is lifted by the lifting means, so that
It is moved to the paper feeding position and is moved to the non-paper receiving position by being lowered.

The elevating means is driven by a drive motor, and when the paper reaches the paper feeding position due to the drive of the drive motor, it is detected by an upper sensor and stopped, and copying is started. After copying is completed, the drive motor is driven in the opposite direction. By this drive, when the paper is lowered and moved to the non-sheet feeding position, it is detected by the lower sensor and the lowering is stopped.

(Problem to be solved by the invention) However, in the past, a lower sensor was required to detect the lower limit position of the paper, which increased costs, required a large space, and made controlling the drive motor troublesome. There was a problem.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a paper feeding device that can stop paper at a non-feeding position without using a lower sensor.

[Structure of the Invention] (Means for Solving the Problems) In order to solve the above-mentioned problems, the present invention provides a paper storage section for storing paper, and a holder provided in the paper storage section for placing the above-mentioned paper. a board, a lifting means for raising and lowering the mounting plate to move the paper to a paper feeding position and a non-paper feeding position, and taking out the paper moved to the paper feeding position by the lifting means and feeding it to the paper receiving section. a drive source connected to the elevating means via a power transmitting means to drive the elevating means; and a drive source provided on the power transmitting means that generates power when the placing plate is lowered to a non-sheet feeding position. A torque limiter is provided to cut off the transmission of the torque.

(Function) The driving of the drive source operates the lifting means via the torque limiter, and when the loading plate is lowered and reaches the non-paper feeding position, the torque limiter operates and power transmission is cut off. The lowering of the mounting plate is stopped.

(Example) The present invention will be described below with reference to an example shown in the drawings.

FIG. 2 shows the appearance of the entire device, and numeral 1 in the figure is the main body of the device. This device main body 1 has upper and lower storage stands 101, 1.
It is placed on the top surface of 02.

Figure 4 shows the internal configuration of the entire device.
Inside are charging, exposure, development, transfer, and peeling.

Image forming process constituent means 2 for cleaning, neutralizing, fixing, etc. are built in, and a document mounting table (hereinafter referred to as a platen glass) 3 on which a document is set is provided on the top surface of the main body 1 of the apparatus.

Further, a manual paper feed tray 10 is provided on one side of the apparatus main body 1, and a tray 12 for collecting sheets on which images have been fixed is provided on the other side.

The image forming process configuration means 2 has the following configuration. That is, a drum-shaped photoreceptor 20 as an image carrier is arranged approximately in the center of the apparatus main body 1, and around this photoreceptor 20, along the rotation direction,
Charging device 21, exposure section 22a of exposure device (optical system) 22
1 developing device 23 a s 23 b s transfer charger 25. Peeling charger 26. Cleaning devices 27 and the like are sequentially arranged.

Further, in the apparatus main body 1, paper automatically fed from the paper feed cassettes 61 to 64, which will be described later, is transferred to an image transfer section 30 between the photoreceptor 20 and the transfer charger 25.
A paper transport path 31 is formed that leads to the tray 12 provided on the left side of the apparatus main body 1 through the paper transport path 31 .

A registration roller pair 32 is arranged on the upstream side of the image transfer section 30 of the paper conveyance path 31, and a fixing device 3 consisting of a heat roller 33a and a press roller 33b is disposed on the downstream side.
3 and discharge rollers 34a and 34b are arranged.

Further, a conveyor belt 35 is disposed between the peeling charger 26 and the fixing device 33.

Further, a gate 61 is provided between the paper ejection rollers 34a and 34b, and when this gate 61 is rotated upward, the paper is sent to a conveyance path 62 for double-sided copying below, and the gate 61 is rotated upward. When rotated downward, the paper is delivered to the paper ejection roller 34b.
It is designed to be sent to and discharged.

A plurality of pairs of feed rollers 63 are arranged at predetermined intervals on the conveyance path 62, and these feed rollers 63...
The paper is conveyed by. This paper is sent in an inverted state to the introduction side of the registration rollers 32 via the supply path 66.

Further, the exposure device 22 illuminates the document set on the platen glass 3 with an exposure lamp 41 as a light source surrounded by a reflector 40, and directs the reflected light from the document to a first reflection mirror 42, a second reflection mirror 42, and a second reflection mirror 42. It is guided to the lens 45 via the reflective mirror 43 and the third reflective mirror 44 in order, and then,
The light transmitted through the lens 45 is guided to the photoreceptor 20 through a fourth reflective mirror 46, a fifth reflective mirror 47, a sixth reflective mirror 48, and a slit glass 49 in this order.

The exposure lamp 41 and the first reflection mirror 42 surrounded by the reflector 40 are mounted on a first carriage (not shown) that is movable back and forth along the lower surface of the platen glass 3, and Mirror 43 and third
The reflective mirror 44 of the second carriage (not shown) moves in the same direction at half the speed of the first carriage.
The first and second carriages move from left to right in the state shown in FIG. 1 using the carriage shaft as a guide, thereby applying light to the original set on the platen glass 3. is scanned to expose an image corresponding to the original onto the photoreceptor 20 by slit exposure.

In addition, numeral 51 in the figure is an opening/closing cover for opening and closing the platen glass 3.

By the way, the above upper and lower cassette storage stands 101°102
There are paper feed cassettes 61 and 62 as paper storage units inside the
．． 63 and 64 are stored so that they can be accessed and removed at will.

The paper feed cassettes 61, 62, 63, and 64 contain sheets of paper P, P2, . P, , P4 are stored therein, and a handle 67 is provided on the front surface.

Papers P, , P2 . in the paper feed cassettes 61 , 62 , 63 , 64 . P,,P, is a bottom plate (mounting plate) that can move up and down.
It is loaded on 65.

Further, near the loaded portion of the paper feed cassettes 61, 62□63°64, there is a pickup roller 71 serving as a paper feeding means for taking out sheets one by one, and a pickup roller 71 for receiving the sheets taken out through the pickup roller 71. Separation and conveyance means 74 each consisting of a conveyance roller 72 and a separation roller 73 are provided.

Further, the separating and conveying means 74... are the guides 75...
It is connected to the communication path 76 via.

The communication path 76 is provided substantially vertically so as to pass through the bottom, upper and lower storage tables 101 and 102 of the copying machine main body 1. This communication path 76 has a guide plate 77...
and a feed roller 78...

On the other hand, as shown in FIG. 5, the paper feed cassettes 61 to 64 inserted into the cassette storage stands 101 and 102 are raised and lowered by levers 81 as raising and lowering means.

The lever 81 is fixed to a drive shaft 82, and as shown in FIG. 6, the drive shaft 82 is rotatably held by a holding frame 83.

One end of the drive shaft 82 protrudes from the holding frame 83, and a drive motor 85 serving as a drive source that rotates in forward and reverse directions is connected to this protrusion via a power transmission means 84.

The power transmission means 84 includes a drive belt 86, a pulley 87,
It is composed of a reduction gear 88, gears 89, 90°91, 92, and a fan gear 93. Further, as shown in FIG. 1, a spring clutch 94 as a torque limiter is provided between the reduction gear 88 and the gear 89.

When the drive motor 85 is driven in the forward direction and the pulley 87 is rotated in the direction indicated by the solid arrow M, the spring clutch 94 operates in the tightening direction to transmit power, and the drive motor 85 is driven in the opposite direction. When the pulley 87 rotates in the direction indicated by the dashed arrow N, it loosens and disconnects the power transmission.

As shown in FIG. 5, a sensor 95 is provided above the pickup roller 71 to detect the upper limit position (paper feeding position) of the paper.

When copying, a document is first set on the platen glass 3, and then a copy button (not shown) is turned on. As a result, the exposure lamp 41 is turned on and the first and second carriages are moved along the platen glass 3.

By this movement, light is scanned on the original, and the light reflected via this original is reflected on the first to third reflection mirrors 42 43
．． 44 to a lens 45, and further passes through this lens 45 to fourth to sixth reflecting mirrors 46, 47 .
The image is formed on the photoreceptor 20 via 48. The surface of the photoreceptor 20 is charged by a charging device 21, and the image is formed on the surface of the photoreceptor 20. An electrostatic latent image of the original is formed. This electrostatic latent image is developed by supplying developer with the developing device 23a or 23b.

On the other hand, at this time, the bottom plate 65 of the paper feed cassette 61 (-64) of the designated paper size is lifted by the lever 81, and the paper P, (-P4N) is raised to the paper feeding position and taken out by the pickup roller 74.

That is, the drive motor 85 is rotationally driven in the forward direction, and the pulley 87 is rotated in the direction shown by the solid arrow M in FIG. 6 via the belt 86. As a result, the reduction gear 88 rotates in the direction shown by the solid arrow F, and the spring clutch 9
4 is tightened to transmit power. This power is transmitted to the sector gear 93 via the gears 89, 90°91, 92, and the sector gear 93 is rotated in the direction of the solid arrow G.

This rotation of the fan gear 93 causes the lever 81 to be raised via the drive shaft 82, the bottom plate 65 is raised, and the sheets P, (-P4) are raised.

Then, paper P1 (~P4) is at the upper limit position (paper feeding position)
As shown in FIG.
) is retrieved. This removed paper P, (~P a
) are separated one by one by the separating and conveying means 37 and sent to the registration rollers 32. After the paper is aligned by the registration rollers 32, it is sent to the image transfer section 30 between the photoconductor 20 and the transfer charger 25, and then
The developer image on 0 is transferred. The paper to which this image has been transferred is peeled off from the photoreceptor 20 by the action of the peeling charger 26, and is conveyed by the conveyor belt 35. This paper is then sent to the fixing device 33, where the image is fixed.
Normally, the paper is discharged onto the discharge tray 12 via the gate 61 and the paper discharge roller 34b.

Note that during double-sided copying, the gate 61 rotates upward and the paper is sent to the conveyance path 62, and from this conveyance path 62 it is sent to the registration rollers 32 in an inverted state via the supply path 66.
Here, after being aligned, it is sent to the image transfer section 30 and the image is transferred.

The paper onto which this image has been transferred is sent to the fixing device 33 via the conveyance belt 31, where it is fixed and then ejected via the ejection roller 34b.

On the other hand, when the copying is completed, the drive motor 85 is rotated in the opposite direction, and the pulley 87 is moved via the belt 86 by the broken line arrow N.
rotated in the direction of As a result, the reduction gear 88 rotates in the direction of the broken line arrow J, and the spring clutch 94 is rotated in the direction of loosening, and the generated idle torque transmits power to the fan gear 93 via the gear 89°90.91 to the direction shown by the broken line arrow E. It is rotated in the direction shown.

As a result, when the drive shaft 82 rotates in the same direction and the lever 81 comes into contact with the base 96, the spring clutch 94 will slip any further, so the lever 81 will be in a stopped state and after a certain period of time, the drive motor 85 will stop. .

As mentioned above, after copying is completed, the paper feed cassette 61 (~
64) lowers and the paper P1 (~P4) reaches the lower limit position (non-feeding position), the spring clutch 94
slips and the lever 81 comes to a halt, so there is no need for a sensor to detect the lower limit position (non-feeding position) of paper P+ (~P4) and stop the drive motor 85 as in the past. .

Therefore, costs can be reduced, control becomes easier, and space can be saved.

[Effects of the Invention] As explained above, according to the present invention, when the placement plate on which the paper is placed in the paper storage section descends and the paper reaches the non-feeding position, the power transmission connection means Since the transmission of the paper is cut off, there is no need to use a sensor to detect the non-feeding position of the paper and stop the drive motor as in the conventional case.

Therefore, it is possible to reduce costs, facilitate control, and save space.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention; FIG. 1 is a perspective view showing a reduction gear and a spring clutch, FIG. 2 is a perspective view showing the entire device, and FIG. 3 is a state in which the paper feed cassette is pulled out. FIG. 4 is a schematic diagram showing the inside of the entire apparatus, FIG. 5 is a diagram showing the elevating mechanism of the bottom plate of the paper feed cassette, and FIG. 6 is a perspective view thereof. P1-P4...paper, 61-64...paper feed cassette (paper storage section), 65...bottom plate (placing plate), 71...
・Pickup roller (paper feeding means), 81...Shuku=
(elevating means), 84... power transmission means, 85... drive motor (drive source), 94... spring clutch (
torque limiter). Applicant's representative Patent attorney Takehiko Suzue Figure 1 Figure 12 Figure 3

Claims (1)

[Scope of Claims] A paper storage unit that stores paper; a mounting plate provided within the paper storage unit and on which the paper is placed; and a mounting plate that is moved up and down to place the paper at a paper feeding position and a non-feeding position. an elevating means for moving the paper to a paper position; a paper feeding means for taking out the paper moved to the paper feeding position by the elevating means and feeding it to a paper receiving section; and a elevating means connected to the elevating means via a power transmission means; A paper feeding device comprising: a drive source for driving the means; and a torque limiter provided on the power transmission means to cut off power transmission when the placement plate is lowered to a non-sheet feeding position.