JPH0320351B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a paper holding device for a printer, etc., which is suitable for use in a printer that prints while feeding a long paper.

Conventionally, in this type of printer, a paper presser roller is used to prevent the recording paper from lifting off the platen when the recording paper is wound and fed around the platen. However, conventional paper press rollers are cylindrical and tend to sag or wrinkle in the center when the recording paper is fed, making it difficult to achieve complete adhesion. Therefore, when the printing method is an inkjet method, etc., there is a large factor that the printing becomes unclear. In particular, in printers that print by moving the recording paper back and forth, the recording paper tends to sag and wrinkle significantly, which is a problem in inkjet printers.

The present invention has been made in view of these points, and provides a paper holding device for printers, etc., which can effectively prevent the occurrence of sagging and wrinkles in recording paper wound around a cylinder such as a platen. The purpose is to obtain.

In the present invention, a pair of arms that can be raised and lowered are provided on a cylinder around which recording paper is wound, and a paper press roller that contacts the cylinder is moved inward from these arms in a direction perpendicular to its axis. Since the rotation angle of the paper press roller is limited to a certain range by the rotation angle regulating body, each paper press roller forms a V-shape when the recording paper is fed. Since both sides of the recording paper are pulled outward depending on the feeding direction of the recording paper, no matter which direction the recording paper moves, sagging occurs in the middle, causing lifting or wrinkles. It is designed so that there are no errors.

An embodiment of the present invention will be described based on the drawings. First, a platen 1 serving as a cylinder is rotatably provided between frames (not shown), and a recording paper 2 is wound around the platen 1. Platen 1 like this
Two guide shafts 3 are provided in parallel at the front part of the
A carriage 4 is provided on these guide shafts 3 so as to be able to reciprocate. A printing head 6 having a nozzle surface 5 facing the platen 1 is attached to such a carriage 4. As shown in FIG.

Next, a guide plate 7 is provided at the upper front part of the platen 1 in parallel with the platen 1.
Square teeth 8 are formed at equal pitches on the platen 1 side of the guide plate 7. Such a guide plate 7 is provided with two holders 10 that are formed in a U-shape and have square holes 9 that are fit into the guide plate 7.
A holding protrusion 12 having a hole 11 and protruding with a predetermined width is formed on the front side of the holding protrusion 12 . An arm 13 made of sheet metal is attached to each of the holding protrusions 12. Flanges 15 having fitting holes 14 are formed at the bases of these arms 13 on both sides of the holding protrusion 12, and are rotatably held by pins 16. Further, three clamp claws 17 that engage with the teeth 8 of the guide plate 7 are elastically provided from the intermediate portion by being separated so as to move independently. These clamp claws 17 are provided every 1/2 pitch,
Therefore, even if the pitch of tooth 8 is not made finer, it will be 1/2
The arm 13 can be positioned with the pitch. Further, a plurality of positioning notches 18 are formed on the side surface of the arm 13.

Furthermore, a block 19 is fixed to the lower end of the arm 13. A shaft 20 that passes through the block 19 together with the arm 13 and is rotatably mounted is vertically mounted on the block 19.
At the upper end of the pin 21 is a relatively long stopper.
are provided along the longitudinal direction of the arm 13,
A block body 22 is fixed to the lower end of the shaft 20. This block body 22 is provided with a horizontal shaft 23, and a paper pressing roller 24 is rotatably provided on this horizontal shaft 23.

Next, a rotation angle regulating body 2 is attached to the arm 13.
5 is installed. This rotation angle regulating body 25
A bent portion 26 for holding the arm 13 is formed in the arm 13, and an elastic leg 28 having a claw 27 that engages with and disengages from the positioning notch 18 extends from one side. Further, an opening 29 is formed in the rotation angle regulating body 25, and abutting surfaces 30, on which the pin 21 abuts, are formed on both side edges of the opening 29 to face each other.

In this configuration, the recording paper 2 is wound around the platen 1, and the paper pressing rollers 24 are joined near both side edges of the recording paper 2. At this time, arm 13
When the holder 10 is raised up, the clamp claws 17 are disengaged from the teeth 8 of the guide plate 7, thereby causing the holder 10 to reciprocate along the guide plate 7. Then, after setting the position appropriately and folding down the arm 13, the clamp claw 1
7 meshes with the recess of the tooth 8. Then, the clamp claw 17 that has not fallen into the recess engages with a relatively shallow engagement groove 31 formed in the longitudinal direction along the top surface of the teeth 8 of the guide plate 7, and the arm 13 is elastically moved. It has the effect of keeping it in place. Therefore, the paper pressing force of the paper pressing roller 24 is maintained by this holding force.

When the recording paper 2 advances in this state, the paper pressing roller 24 is inclined in the direction in which the inner portion advances in the direction of travel, and as the recording paper 2 advances in this state, the recording paper 2 is pulled in both directions. Platen 1
closely adhere to. Then, when the traveling direction of the recording paper 2 is reversed, the inclination direction of the paper pressing roller 24 is also reversed to bring the recording paper 2 into close contact with the platen 1.

During use, the width of the recording paper 2 varies; at this time, the arm 13 is raised, moved along the guide plate 7, and then brought down at an appropriate position as described above. At this time, the arm 13 is positioned by the engagement between the clamp claw 17 and the teeth 8, but even if the pitch of the teeth 8 is made coarser and the width of the clamp claw 17 is increased, at least 1/2 of the tooth 8 Positioning is possible with an accuracy of 2 pitches. Therefore, in this type of product where the lateral pressure becomes large, the clamp claw 17 having a large strength provides excellent durability.

Furthermore, the inclination of the paper pressing roller 24 has a large effect on the tensile force and rolling force on the recording paper 2, but in order to change the degree of inclination, the rotation angle regulating body 25 can be moved back and forth to control the pin 21. Adjustment is made by changing the state of contact with the contact surface 30. In addition,
When the tilt angle can be fixed, the rotation angle regulating body 2
5 and then fix the stopper that contacts the pin 21 to the arm 13.

As described above, the present invention provides a pair of arms that are movable up and down on the cylinder around which recording paper is wound, and the contact points at the tips of these arms are deviated inward and perpendicular to the axis thereof. A paper presser roller is provided that rotates in the direction in which the paper presser rolls, and the rotation angle of the paper presser roller is limited to a certain range by a rotation angle regulating body. This allows the recording paper to be closely bonded to the platen, thereby preventing sagging or wrinkles in the recording paper, and in inkjet printing machines, the nozzle surface and the surface of the recording paper are closely connected. The spacing is constant, and it has the advantage of being able to perform uniform printing.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, in which Fig. 1 is a vertical side view, Fig. 2 is an exploded perspective view, and Figs. 3 and 4 show the direction of the paper pressing roller according to the direction of travel of the recording paper. FIG. 5 is a plan view showing the relationship between the teeth of the guide plate and the clamp claw, FIG. 6 is a sectional view taken along line A-A in FIG. 5, and FIG. It is a BB sectional view in . 1...Platen (cylindrical body), 2...Recording paper, 13
... Arm, 21 ... Pin (stopper), 24
... Paper press roller, 25 ... Rotation angle regulating body, 3
0...Abutment surface.

Claims (1)

[Scope of Claims] 1. A pair of arms parallel to each other are provided in a cylindrical body around which recording paper is wound so as to be able to rise and fall freely, and a shaft with an axis directed toward the cylindrical body is attached to the tip of each arm. A block body is fixed to one end of the shaft, and a paper pressing roller which is perpendicular to the shaft and located between the pair of arms is rotatably mounted to the block body, A paper holding device for a printer or the like, characterized in that a stopper projecting from the other end of the arm is substantially orthogonal to the axis of the paper holding device, and a rotation angle regulating body that comes into contact with the stopper is provided at the tip of the arm. 2 A pair of arms parallel to each other are provided on the cylinder body around which the recording paper is wound, and a shaft whose axis is directed toward the cylinder body is rotatably attached to the tips of these arms. A block body is fixed to one end of the shaft, a paper pressing roller which is perpendicular to the shaft and located between the pair of arms is rotatably attached to the block body, and the shaft is fixed to the other end of the block body. A stopper that is substantially orthogonal to the center is protruded and provided, and a rotation angle regulating body whose facing dimension of a contact surface that contacts the stopper changes with an inclination is provided at the tip of the arm and moves back and forth along the longitudinal direction of the arm. A paper holding device for a printer, etc., characterized in that it is freely provided. 3. Claims 1 and 2, characterized in that a pair of arms that hold the paper press rollers are provided along the cylindrical body so that their positions can be freely adjusted so that the interval between the paper press rollers is adjusted. Paper holding device for printers, etc. described in Section 2.