JPH04260542A - Paper feed device - Google Patents

Abstract

PURPOSE:To provide a paper feed device having a simple structure with which a large number of sheets can be stably fed. CONSTITUTION:The front part 15a of a bottom plate 15 in a paper cassette 1 is supported by a front support 17, and a rear part 15b thereof is supported by a rear support 19. The front support 17 is rotated in the direction of the arrow E by an urging force of a forward drawing spring 31 in the direction of the arrow D so as to elevate the front part 15a of the bottom plate 15. The rear support 19 is rotated in the direction of the arrow C by an urging force of a rearward drawing spring 23 in the direction of the arrow B so as to elevate the rear part 15b of the bottom plate 15. When a large number of sheets P are stacked thereon, the bottom plate 15 is depressed down to the lowermost position. However, as the sheets P are paid out one by one, both supports 17, 19 are rotated to elevate the bottom plate 15, entirely.

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 that supplies paper to an apparatus body such as a printer using a paper feeding cassette or the like.

0002

[Prior Art] Conventionally, a paper feed cassette that can hold a large number of sheets of paper has been used as a device for supplying paper to the main body of a printing device such as a printer. It is removably attached to a paper feed section for mounting a cassette on the main body of the machine.

[0003] The paper feed cassette is usually a box-shaped container with an open top, and a bottom plate on which paper is directly placed is attached to the inside bottom of the container. This bottom plate is located at the leading edge of the paper cassette in the paper feeding direction.
The paper is lifted upward by being biased upward by the spring member.

On the other hand, a paper feed roller, such as a half-moon roller, is attached to the paper feed section on the main body side above the leading edge side in the paper feed direction for feeding the paper from the paper feed cassette.

In other words, the conventional paper feeding device uses a spring member to urge the leading edge of the bottom plate upward to lift the leading edge of the paper upward, and in this state, rotates the half-moon roller to feed the paper. are sent into the main body in order.

[0006]

[Problems to be Solved by the Invention] However, when using the above paper feed cassette, there are the following problems.
It wasn't always suitable.

In other words, when a large amount of paper is placed in a paper cassette and a large number of sheets are to be sequentially supplied by one loading of the paper cassette, if the former paper cassette is used, the paper As the amount decreases, the leading edge of the cassette and the leading edge of the paper gradually move away from each other, making it impossible to feed the paper stably and accurately.

As a countermeasure to this problem, a device has been developed that feeds paper by lifting the entire bottom plate using a motor or the like according to the number of sheets used, in order to load and feed a large amount of paper at once. However, in this case, the device becomes complicated and other problems arise, such as the occurrence of failures and increased manufacturing costs.

The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide a paper feeding device that has a simple configuration and can load and stably supply a large amount of paper. .

0010

[Means for Solving the Problems] In order to achieve this object, the present invention places a plurality of sheets on the bottom plate of a paper feed unit that supplies sheets to the apparatus main body, and urges the bottom plate upward. In a paper feeding device that moves the paper upward by moving the paper upward and sequentially feeds the paper in the paper feeding direction using a paper feeding means, a paper feeding device is provided on the leading end side of the bottom plate in the paper feeding direction, and the leading end side is moved upward. and a rear end side urging means provided on the rear end side of the bottom plate in the paper feeding direction and urging the rear end side upward using a spring. The gist is a paper feeding device that is characterized by the following.

[0011]

[Operation] In the paper feeding device of the present invention, the leading end side of the bottom plate is urged upward by the leading end side biasing means provided on the leading end side of the bottom plate in the paper feeding direction, and the rear end side of the bottom plate in the paper feeding direction is biased upward. The rear end side of the bottom plate is urged upward by the rear end side urging means provided using a spring. As a result, the entire bottom plate is forced upward, which greatly prevents the paper placed on the bottom plate from tilting.As a result, the leading edge of the paper will not shift, allowing you to feed a large amount of paper. is carried out smoothly.

0012

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the paper feeding device of the present invention will be described below with reference to the drawings. FIG. 1 shows an example in which the paper feed cassette 1 of this embodiment is applied to a printer 3. This paper feed cassette 1 stores a large amount of paper P (for example, about 1000 sheets), and stores it in a cassette mounting section 5 at the bottom of the printer 3.
It is removably attached to.

The paper feed cassette 1, as shown in FIG.
Direction of paper feed cassette 1 removal (arrow A) across the partition wall 7
Direction) A paper storage section 9 for storing a large number of papers P is provided at the rear, and an operation chamber 11 in which various operating mechanisms are arranged is provided at the front. Note that wheels 13 are attached to the lower side edge of the paper feed cassette 1 in order to smoothly attach and detach the paper feed cassette 1 to and from the cassette mounting portion 5.

The paper storage section 9 is a box-shaped container with an open top, and a bottom plate 15 on which the paper P is directly placed is disposed at the bottom. The front part 15 of this bottom plate 15
a is supported by a front support 17, which will be described later, and is supported by a rear support 17.
5b is supported by a rear support 19, and these supports 17 and 19 allow the bottom plate 15 to move up and down.

The rear support 19 is a dogleg-shaped member attached to the outside of both side walls 21 of the paper storage section 9, and is rotatable by being pivotally supported at its center portion 19a. One end 19b of this rear support 19 extending upward is a rear tension spring 23.
The other end 19c connected to and extending rearward is connected to the side wall 21
It is pivotally supported by the rear part 15b of the bottom plate 15 through an arcuate opening 25 provided in the bottom plate 15.

[0016] As a result, the rear support 19
Since it rotates in the direction of arrow C by the urging force in the direction of arrow B of No. 3, it functions to raise the rear part 15b of the bottom plate 15. Note that, since the upward movement of the other end 19c of the rear support 19 is restricted by the upper end of the opening 25, the rear portion 15b of the bottom plate 15 only rises to a certain position.

On the other hand, the operation chamber 11 described above includes a handle 27 for pulling out the paper feed cassette 1, a pair of front supports 17 that support the front portion 15a of the bottom plate 15, and a pair of front supports 17 for supporting the front portion 15a of the bottom plate 15.
A pair of locking hooks 29 are provided for locking 7, respectively.

The front support 17 has one end 17 extending upward.
b is a dogleg-shaped member that is pivotally supported, and its central portion 17
A front tension spring 31 is attached to a, and a roller 33 that comes into contact with the back side of the front portion 15a of the bottom plate 15 is attached to the other end 17c extending at the rear. As a result, the front support 17 is rotated in the direction of the arrow E by the biasing force of the front tension spring 31 in the direction of the arrow D, so that it functions to raise the front portion 15a of the bottom plate 15.

Furthermore, the locking hook 29 is used to prevent the paper P from jumping up when the paper P is placed in the paper feed cassette 1, as shown in FIG. 3(A). When the paper P is placed, it engages with a locking hole 35 provided at the end of the bottom 17d of the front support 17 to prevent the front support 17 from moving upward.

[0020] Then, when the paper feed cassette 1 is installed,
As shown in FIG. 3(B), the protrusion 29a of the locking hook 29 comes into contact with the protrusion 37 provided on the bottom 5a of the cassette mounting section 5, and the locking hook 29 is removed from the locking hole 35. The front support 17 is rotated by the biasing force of the front tension spring 31 to lift the paper P upward.

Next, the paper feeding operation of the paper feeding cassette 1 of this embodiment will be explained based on FIG. 4. First, as shown in FIG. 4A, when a large amount of paper P is placed in the paper feed cassette 1 and installed in the cassette mounting section 5, the front support 17, the rear support 19, and both supports 17 , 19 is pushed down to the lowest position.

Next, as shown in FIG. 4(B), the sheets P
is sent out by the paper feed roller 39 or the like, and as the number of sheets P placed in the paper feed cassette 1 decreases, the front support 17 and the rear support 19 are urged upward by the front tension spring 31 and the rear tension spring 23. , the entire bottom plate 15 rises.

Furthermore, as shown in FIG. 4(C), when the number of sheets P placed in the paper feed cassette 1 decreases, the front portion 15a of the bottom plate 15 tilts upward. In other words, the rear support 19
is obstructed by the opening 25 and can only rise to a predetermined position, but the front support 17 can move upwards, so that the front part 15a of the bottom plate 15 rises above the rear part 15b, so that the bottom plate 15 will be tilted to some extent.

In other words, in the paper feed cassette 1 of this embodiment, when there are many sheets of paper P to be placed, the bottom plate 15 is raised as a whole, and when there are few sheets of paper P to be placed, the bottom plate 15 is raised to a predetermined position. 15 rises and from there the front part 1 of the bottom plate 15
Only portion 5a rises and tilts.

Therefore, since the angle of inclination of the bottom plate 15 is small, the position of the leading edge of the paper P is almost the same as the initial position when a large amount of paper P is placed. As a result, the paper P to be placed
It has the advantage that the paper P can be sent out accurately and stably regardless of the amount.

Furthermore, the mechanism for driving the bottom plate 15 is simple, as it only requires a spring and a crank, rather than lifting the entire bottom plate 15 using a motor, etc., and has the advantage of being less likely to break down and reducing manufacturing costs. There is.

[0027] The present invention is not limited to the above embodiments,
It goes without saying that the invention can be implemented in various ways without departing from the gist of the invention. For example, as a configuration for lifting the rear part 15b of the bottom plate 15, the rear part 15b of the bottom plate 15 may be lifted up.
b may be simply raised using a leaf spring or a coil spring. In addition, the rear part 15b of the bottom plate 15 is similar to the front part 15a,
A spring or a crank may be used to lift it to the top.

[0028]

Effects of the Invention As is clear from the detailed description above, according to the present invention, even if the amount of paper loaded on the paper feed section changes, the position of the leading edge of the paper to be fed out does not shift significantly. It is possible to send out sheets of paper in sequence with high precision and stability. Furthermore, since the configuration is simple, there is an advantage that there are fewer failures and manufacturing costs can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing the installed state of a paper feed cassette according to an embodiment of the present invention.

FIG. 2 is a partially cutaway perspective view of the paper feed cassette of this embodiment.

FIG. 3 is an explanatory diagram showing the function of a locking hook.

FIG. 4 is an explanatory diagram showing the operation of the paper feed cassette.

[Explanation of symbols]

1...Paper cassette 15...Bottom plate
23... Rear extension spring 31... Front extension spring 17... Front support
19…back support

Claims (1)

[Claims] Claim 1: A plurality of sheets of paper are placed on the bottom plate of a paper feed unit that supplies the paper to the main body of the apparatus, and the bottom plate is urged upward to move the sheets of paper upward, and the paper is fed. In a paper feeding device that sequentially feeds paper in a direction using a feeding means,
A front end biasing means is provided on the front end side of the bottom plate in the paper feeding direction to bias the front end side upward; 1. A paper feeding device comprising: a rear end side biasing means for biasing upward using the rear end side biasing means.