JPH0357483Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a paper feeding device for a printer, and more particularly to a paper feeding device that can reduce manufacturing costs.

FIG. 1 is an exploded perspective view showing an example of a paper feeding device of a conventional printer. In this figure, 1 is a platen around which recording paper is wound, and 2 is a paper feed guide. This paper feed guide 2 is connected to the peripheral surface 3 of the platen 1.
Guide surface 4 and hole 5 formed in a curved shape corresponding to
The recording paper wound around the platen 1 is guided along the circumferential surface 3 of the platen 1. This paper feed guide 2 is fixed, for example, by screws, to a chassis arranged on a case forming the bottom of the printer. A small roller 6 presses the recording paper wound around the platen 1 against the platen 1, and can be inserted into the hole 5 of the paper feed guide 2. Reference numeral 7 denotes a shaft on which the small roller 6 is attached, and this shaft 7 and the small roller 6 are manufactured separately.

8 is a support member on which the shaft 7 is rotatably supported;
It has a protrusion 9. Reference numeral 10 denotes a rotating member, one end 10a of which is engaged with the protrusion 9, and is rotatable about a shaft (not shown) that is inserted into a hole 11 formed in the center. The support member 8 is this rotating member 10
It is attached so that it can swing freely. 12 is the rotating member 1
A shaft 13 is engaged with the other end 10b of the shaft 1.
This is the release lever attached to 2. 14 has one end engaged in a hole 15 formed in the rotating member 10, and the other end engaged with a chassis (not shown), and urges the rotating member 10 in the direction of the arrow 16 shown in the figure. That is, the coil spring 14 biases the small roller 6 via the support member 8 and the shaft 7 so as to press the recording paper wound around the platen 1.

In the paper feeding device configured as described above, when feeding the recording paper, the release lever 13 is in a predetermined lower position, and the recording paper wound around the platen 1 is moved to the guide surface 4 of the paper feeding guide 2. The small roller 6 is inserted into the hole 5 of the paper feed guide 2 and pressed against the platen 1 by the force of the coil spring 14. Therefore, by rotating the platen 1 in this state, a paper feeding operation can be performed.

Further, when removing recording paper from the platen 1, the release lever 13 is pulled upward from the above-mentioned state, that is, in the direction of the arrow 17, and the shaft 12 is integrally moved with the release lever 13 to release the coil spring 1.
The rotating member 10 rotates in the direction opposite to the direction of the arrow 16, and the shaft 7 and the small roller 6 are rotated through the support member 8. It is removed from the hole 5 of the paper feed guide 2, thereby allowing desired operations such as removing the recording paper.

By the way, in the conventional paper feeding device configured in this way, the small roller 6 and the shaft 7 are provided separately, and the small roller 6 is attached to the recording paper wound around the platen 1. Since the support member 8 and the rotating member 10 are required for pressing, there is a problem that the number of members increases, the number of assembly steps increases, and therefore the manufacturing cost increases. Furthermore, since the small roller 6 is attached to a shaft 7, and this shaft 7 is supported by support members 8 installed on both sides of the platen 3, the shaft 7 is warped and dimensional accuracy is not achieved. In this case, since the pressing force of each small roller 6 against the platen 3 changes (especially when feeding wide paper), the paper is not fed uniformly, resulting in so-called skew feeding.

The present invention was devised in view of the actual situation in the prior art, and its purpose is to reduce the number of parts and assembly steps, and to uniformly apply pressure of each small roller to the platen. An object of the present invention is to provide a paper feeding device for a printer.

Hereinafter, the present invention will be explained based on the drawings.

FIG. 2 is an exploded perspective view of essential parts showing an embodiment of the paper feeding device of the printer of the present invention.

In this FIG. 2, numeral 1 is a platen similar to that described above, and numeral 20 is a paper feed guide. This paper feed guide 20 is made of synthetic resin, for example, by integral molding with a case forming the bottom of the printer (not shown), and has a curved surface corresponding to the peripheral surface 3 of the platen 1 around which recording paper (not shown) is wound. It has a guide surface 21 formed into a shape. A chassis 22 (not shown) is disposed on the top surface of a case forming the bottom of the printer, and has a hole 23 through which the paper feed guide 20 can be inserted, and a cut-and-raised portion 24 . 25 is a small roller that presses the recording paper wound around the platen 1; 26 is a shaft of the small roller 25;
is constructed by integral molding, and is made of, for example, synthetic resin.

Reference numeral 27 denotes a support member that rotatably supports a shaft 26 formed integrally with the small roller 25. The support member 27 has an upper portion corresponding to the circumferential surface 3 of the platen 1, and supports the recording paper wound around the platen 1. A substantially arc-shaped guide surface 29 is formed to guide the surface, and both ends of this guide surface 29 have holes 28 into which the shafts 26 of the small rollers 25 are inserted, and projections 3 are provided on both sides of the lower part.
0, and a rectangular cylindrical portion, for example, which is not clearly shown in FIG. 2, is provided at the center of the lower part. 31
is a spring that is engaged with the cut-and-raised portion 24 of the chassis 22 mentioned above, and the spring 31 and the cut-and-raised portion 24 are housed inside the above-mentioned rectangular cylinder portion provided at the center of the lower part of the support member 27. The support member 27 is urged upward (towards the platen) by the spring 31, that is, in the direction of the arrow 32.

Reference numeral 33 is a shaft having a circular cross section, for example, and is arranged so that its body 34 is engaged with the bent portion 35 of the chassis 22, and the protrusion 3 of the aforementioned support member 27.
It has a U-shaped portion 36 that engages with 0. In addition,
This U-shaped portion 36, the above-mentioned support member 27 that engages with this U-shaped portion 36, the cut and raised portion 24 provided on the chassis 22, the spring 31, and the two portions arranged on both sides of the cut and raised portion 24. Although only one set of paper feed guides 20 and the like are depicted in FIG.
There are sets. Reference numeral 37 denotes a bearing that rotatably supports a substantially central portion of the shaft 33 in the longitudinal direction as illustrated by arrows 38 and 39. This bearing 37 is attached to, for example, a rising portion 40 of the chassis 22 with a screw. 41 is a release lever, for example, the shaft 33
is engaged with the end of the

In the paper feeding device configured in this way, when feeding the recording paper, the release lever 41 is moved to the shaft 3.
The support member 27 is biased by the spring 31 and is in a predetermined upper position, and the small roller 25 supported by the support member 27 is moved toward the platen 1. The recording paper being wound around the platen 1 is pressed against the platen 1, and the shaft 33 engages with the protrusion 30 of the support member 27 and rotates in the direction of the arrow 38. Part 2
The sheet is guided along the circumferential surface 3 of the platen 1 by the guide surface 29 of the paper feed guide 7 and the guide surface 21 of the paper feed guide 20 . Therefore, by rotating the platen 1 in this state, a paper feeding operation can be performed.

Further, when removing recording paper from the platen 1, the release lever 41 is pushed downward, that is, in the direction of the arrow 42;
1, the shaft 33 rotates in the direction of arrow 39 against the spring force of the spring 31, thereby pushing down the support member 27 and the small roller 25.
A sufficient gap is formed between the small roller 25 and the platen 1, allowing desired operations such as removing the recording paper.

In one embodiment configured in this manner, the paper feed guide 20 is integrally molded into the case that forms the bottom of the printer, so the number of parts can be reduced, and the paper feed guide 20 Since no assembly work is required, the number of assembly steps can be reduced.

Further, the small roller 25 and the shaft 26 are integrally formed, so that the movement of the release lever 41 is transmitted to the support member 27 only by the rotation of one shaft 33. Therefore, from a different viewpoint than the above, the number of parts can be reduced, and therefore the number of assembly steps can be reduced.

In addition, in this embodiment, the paper feed guide 2
Separately from the guide surface 21 of 0, a guide surface 29 for guiding the recording paper is provided on the upper part of the support member 27 disposed between these paper feed guides 20, thereby realizing a good paper feed operation. be able to.

Furthermore, in this embodiment, a pair of small rollers 25 are rotatably supported at both ends of the upper surface of a support member 27 located in the middle of the paper feed guide 20, and each support member 27 is supported by a spring 31. Since the small rollers 25 are biased toward the platen 3 by the rollers, all of the small rollers 25 are uniformly pressed against the platen 3 through the paper, making it possible to feed the paper with high precision.

[Effect of idea]

As explained above, according to the present invention, the number of parts and the number of assembly steps can be kept low, and the pressing force of each small roller against the platen can be reduced by the support member that is swingably supported by the elastic member. In addition, the guide surface that guides the recording paper also swings along the circumferential surface of the platen as the support member swings, thereby better guiding and feeding the recording paper along the platen. There is an effect that can be done.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view showing an example of a conventional paper feeding device for a printer, and FIG. 2 is an exploded perspective view of essential parts showing an embodiment of the paper feeding device for a printer according to the present invention. DESCRIPTION OF SYMBOLS 1...Platen, 3...Surrounding surface, 20...Paper feed guide, 21, 29...Guiding surface, 22...Chassis, 23, 28...Hole, 24...Cut-out portion, 25
... small roller, 26 ... shaft, 27 ... support member,
30...Protrusion, 31...Spring, 33...Shaft, 36
... U-shaped part, 37 ... Bearing, 41 ... Release lever.

Claims (1)

[Scope of utility model registration request] a platen, a small roller placed to face the platen and press the recording paper wound around the platen against the platen, and a fixed guide surface integrally formed in the case along the circumferential surface of the platen. a plurality of support members installed along the axial direction of the platen, each of which rotatably supports a pair of the small rollers; an elastic member that urges the support member toward the platen; In the paper feeding device of the printer, the support member is provided with a release lever that operates to separate the support member from the platen against the biasing force of an elastic member, and the support member corresponds to the circumferential surface of the platen and is attached to the platen. a substantially arc-shaped movable guide surface that guides the wound recording paper along the circumferential surface of the platen, a support portion that rotatably supports the small roller at both ends of the guide surface, and the movable guide. one end of the elastic member is attached to the case, the other end is brought into contact with the support member, and the support member is rocked by the elastic member. A shaft is provided that has a U-shaped portion that is movably supported and urges the supporting member toward the platen, and is operated in conjunction with the release lever, and the U-shaped portion is connected to the pair of supporting members. When the shaft is engaged with each of the projections and the release lever is actuated to rotate the shaft, the support member is separated from the platen by the U-shaped portion through the projections against the elastic member. A paper feeding device for a printer that is characterized by: