JPH04333435A - Paper feeding device - Google Patents

Abstract

PURPOSE:To make a delivery roller part rotatable to a separation roller part to the pulling-out and pushing-in action of a cassette, by providing a rotation lever rotating with a first shaft as a center according to the rotation of a cam lever. CONSTITUTION:When the drive means of a paper feeding device is turning on, sheets 22 are fed with a delivery roller 16 and a separation roller 12 rotated with a drive gear 10, however a gear 29 is not rotatable because it is loosely engaged with a first shaft 11. When the sheets 22 are fed up to be supplied, the pulling-out of a cassette 3 causes a cam lever 24 to be slidably moved along a roller 23 provided on the side wall 2a of a cassette casing 2, and when a paper feeding mechanism 6 comes outside the cassette casing 2, the outer periphery of the other side arm 24b is abutted to the outer periphery of a roller 23 to begin the rotation of the cam lever 24, a gear 29 engaging with the tooth form 26 of the cam lever 24 is rotated to turn a rotation lever 28, and an arm 14 engaging via a pin 31 is rotated together, consequently a delivery roller part 8 is rotated to the first shaft 11.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper feeding device used in electrophotographic printers and the like.

0002

2. Description of the Related Art Generally, a paper feeding device used in an electrophotographic printer or the like feeds out cut sheets with a feed roller, separates the sheets one by one with a separation roller, and feeds the sheets to a printing device.

FIG. 3 is a plan view of a conventional paper feeding device.
FIG. 4 is a cross-sectional view taken along the line AA in FIG. 3. The paper feeding device 1 consists of a cassette housing 2 and a cassette 3. The cassette 3 includes a cassette frame 4, a paper stacking plate 5, and a paper feeding mechanism 6. The paper feeding mechanism 6 includes a separating roller section 7 and a feeding roller section 8.
and a gear train 9. The separation roller section 7 consists of a first shaft 11 having a drive gear 10 fixed to one end thereof and pivotally supported on the cassette frame 4 at both ends, and a separation roller provided at the center of the first shaft 11. The feeding roller section 8 is an arm 1 rotatably provided at both ends of a first shaft 11.
3 and 14, a second shaft 15 whose both ends are rotatably provided on the arms 13 and 14, and a feeding roller 16 provided at the center of the second shaft 14. The gear train 9 is rotatably supported by a first gear 17 fixed to a first shaft 11, a second gear 18 fixed to a second shaft 15, and an arm 14, and is connected to a first gear 17 and a second gear 18 fixed to a second shaft 15. It consists of a third gear 19 in mesh with each other. As shown in FIG. 4, a paper guide section 20 is provided at the upper front surface of the cassette frame 4, and a biased pad 21 is in contact with the roller surface of the separation roller 12.

When a drive means (not shown) provided on the side wall of the cassette housing 2 is turned on, the drive gear 10 rotates in the direction of arrow C as shown in FIG. Therefore, the separating roller 12 and the feeding roller 16 also rotate in the direction of arrow C in synchronization. The paper 22 stacked on the paper stacking plate 5 is fed out by a delivery roller 16, separated one by one by a separation roller 12 and a pad 21, and fed from a paper guide section 20 in the direction of arrow D. When replenishing paper 22, grip the handle 4a shown in FIG. 3 and pull out the cassette 3 in the direction of arrow E along a guide (not shown) provided in the cassette housing 2. Next, the feeding roller section 8 is rotated in the direction of arrow F with respect to the separation roller section 7, as shown in FIG. Then, the paper 22 is replenished, and the feeding roller section 8 is rotated in the direction of arrow G, so that the feeding roller 16
is brought into contact with the paper 22, and the cassette 3 is pushed in the direction of arrow H.

[0005]

[Problems to be Solved by the Invention] With conventional paper feeding devices, when an inexperienced person replenishes paper, he or she may forget to return the feeding roller section and push the cassette into the cassette housing. There was a problem in that the feeding roller part was destroyed. SUMMARY OF THE INVENTION An object of the present invention is to provide a paper feeding device in which a feeding roller section rotates relative to a separation roller section in accordance with the pulling out and pushing operations of a cassette.

[0006]

[Means for Solving the Problems] In order to achieve the above object, in the paper feeding device of the present invention, a rotation fulcrum is provided on the side wall of the cassette casing and a cassette frame, and the cassette frame is biased. A cam lever having an outer cam surface in contact with the outer periphery of the roller, and a rotating lever that is loosely fitted to the first and second shafts and rotates about the first shaft in accordance with the rotation of the cam lever. It is something that

[0007]

[Operation] According to the paper feeding device of the present invention, when the cassette is pulled out from the cassette housing, the cam lever having the dogleg-shaped cam surface is biased and comes into contact with the outer periphery of the roller. The rotation is caused by force, and the movement is transmitted to a rotation lever that is loosely fitted to the first and second shafts, and the rotation lever rotates around the first shaft together with the second shaft. Rotate. When the cassette is pushed into the cassette housing, the cassette is stored by following the above-mentioned process in reverse. Therefore,
The delivery roller section rotates relative to the separation roller section in accordance with the pulling out and pushing operations of the cassette.

[0008]

Embodiments Examples of the present invention will be described with reference to the drawings. Note that elements common to each drawing are given the same reference numerals.

FIG. 1 is a plan view of the embodiment. The difference between the present invention and the prior art is that the cam lever 24 and the cassette 3 rotate along rollers 23 provided on the side wall of the cassette housing 2.
When the cassette 3 is inserted into and taken out from the cassette housing 2, the second shaft 15, which is rotatably provided parallel to the first shaft 11, moves to the side wall of the cam lever 2.
4 rotates around the first shaft 11.

FIG. 2 is an enlarged perspective view of the main parts of the cassette.
FIG. 3(a) shows the cassette 3 housed in the cassette housing 2, and FIG. 2(b) shows the cassette 3 pulled out from the cassette housing 2. The cam lever 24 has a generally dogleg-shaped outer shape, and one end of one arm 24a has a rotation fulcrum 25 on the side wall 4b of the cassette 4, and has a tooth shape 26 in an arc shape around the rotation fulcrum 25. . The other end of one arm 24a is connected to the side wall 4b of the cassette 4.
Due to the biasing force of the tension spring 27 provided between the cassette case 2 and the
The roller 23 is in contact with the outer peripheral surface of the roller 23 provided on the side wall 2b. A rotary lever 28 is provided between the drive gear 10 (omitted in FIG. 2) provided at one end of the first shaft 11 and the arm 14 to transmit the movement of the cam lever 24 to the paper feed mechanism 6. The rotating lever 28 has a gear 29 integrated with the one end at one end, and a U-shaped groove 30 at the other end. One end of the rotary lever 28 is rotatably provided on the first shaft 11 through the center of a gear 29, and its teeth mesh with the tooth profile 26 of the cam lever 24. Further, the groove 30 at the other end engages with a pin 31 provided on the arm 14 on both sides.

Next, the operation will be explained. As described in the prior art section, when the drive means (not shown) provided on the side wall 2a of the cassette housing 2 is turned on, the drive gear 10 rotates the feed roller 16 and the separation roller 12 to feed the paper 22. At this time, the gear 2 provided at one end of the rotating lever 28
9 is rotatable relative to the first shaft 11, that is, it is loosely fitted, so it does not rotate. When the paper 22 has been completely fed and is to be replenished, the cassette 3 is pulled out in the direction of arrow E. At this time, the cam lever 24 is attached to the side wall 2a of the cassette housing 2.
It slides along rollers 23 provided in the. Cam lever 2 is
Since it has a dogleg shape, the outer periphery of one arm 24a initially slides along the outer periphery of the roller 23, and the cam lever 24
The movement of is unchanged. When the cassette 3 is further pulled out and the paper feed mechanism 6 comes out of the cassette housing 2, the other arm 2
The outer periphery of 4b contacts the outer periphery of the roller 23, and the cam lever 24
begins to rotate in the direction of arrow I as shown in FIG. 2(b). When the cam lever 24 begins to rotate in the direction of arrow I, the gear 29 meshing with the tooth profile 26 of the cam lever 24 rotates in the J direction. When the gear 29 rotates, the rotating lever 28 integrated with the gear 29 also rotates in the direction of arrow F. When the rotary lever 28 rotates, the arm 14 engaged with the rotary lever 28 through the pin 31 also rotates, so that the feeding roller portion 8 is moved in the direction of the arrow F relative to the first shaft 11. It will rotate to. When the cassette 3 is pushed into the cassette housing 2, the cassette 3 is housed in the cassette housing 2 through the reverse process of the above-described operation.

In this embodiment, the structure of the rotating lever that transmits the movement of the cam lever to the paper feeding mechanism is integrated with the gear, but like the cam lever, a tooth profile is provided directly on the outer periphery of one end of the rotating lever. Good too.

[0013]Also, although the rotating lever and the arm are separated and engaged by a pin provided on the rotating lever and a groove provided at the end of the arm, it is not possible to integrate the rotating lever and the arm. good.

Further, although the tooth profile is used as the mechanism for transmitting the movement of the cam lever to the paper feeding mechanism, a pulley and a belt may also be used. In this case, the pivot point does not have to be one end of the cam lever.

[0015] Also, one cam lever and one rotating lever each.
They may be provided in pairs and may be provided symmetrically.

[0016]

[Effects of the Invention] Since the present invention is constructed as described above, it produces the effects described below. By rotating the rotating lever loosely fitted on the first and second shafts in accordance with the movement of the cam lever, the feeding roller section rotates around the separating roller section in accordance with the movement of inserting and removing the cassette. This eliminates the need to manually rotate the feeding roller section each time when replenishing paper. Furthermore, there is no possibility of forgetting to return the feeding roller section after replenishing paper, pushing the cassette into the cassette housing, and damaging the feeding roller section, etc.

[Brief explanation of drawings]

FIG. 1 is a plan view of an embodiment.

FIG. 2 is an enlarged perspective view of essential parts of the cassette.

FIG. 3 is a plan view of a conventional paper feeding device.

FIG. 4 is a cross-sectional view taken along the line AA in FIG. 3;

FIG. 5 is an explanatory diagram at the time of paper replenishment.

[Explanation of symbols]

2 Cassette case 3 Cassette 6 Paper feeding mechanism 7 Separation roller part 8　　　Feeding roller part 9 Gear train 11 First shaft 12 Separation roller 15 Second shaft 16 Feeding roller 23 Koro 24 Cam lever 28 Rotating lever

Claims (1)

[Claims] Claim 1: A first shaft having a separation roller and rotatably supported at both ends on a cassette frame;
In a paper feeding device in which a second shaft having a feeding roller is rotatably provided in parallel and takes a cassette into and out of a cassette housing, a roller provided on the side wall of the cassette housing and a rotation fulcrum on the cassette frame are used. and a cam lever whose outer periphery cam surface is in sliding contact with the roller and is loosely fitted to the first and second shafts, and rotates about the first shaft in accordance with the rotation of the cam lever. 1. A paper feeding device comprising a rotating lever, wherein when a cassette is inserted into or removed from a cassette housing, a second shaft rotates relative to the first shaft.