JPH05286191A - Form clamping device - Google Patents

Abstract

PURPOSE:To supply a section between a clamping arm and a clamping bar with a form positively by giving a locating pin with an impulse by a cam and pushing the clamping bar against a back plate before the cam is brought into contact with a lever opening the clamping arm and positioning a clamper. CONSTITUTION:Recessed sections 19 are formed on both end sides of a clamping bar 10 respectively, and locating pins 22 are mounted slidingly to bearing support plates 20 fixed to back plates 9 through bearings. The locating pins 22 are energized in the direction that they are detached from a clamper 8 by springs 23 at all times. Consequently, when the locating pins 22 are set up previously, pin pushing cams 24 installed onto the same shaft as a cam 7 push the locating pins 22 before the cam 7 collides with a lever 15, the tips of the locating pins 22 are intruded into the recessed sections 19 of the clamping bar 10, and the clamping bar 10 is pushed against the back plates 9 and the clamper 8 is positioned. Accordingly, the movement of the clamping bar 10 by the rotation of the cam 7 in the back plates 9 is prevented positively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper clamp device which is provided, for example, in a paper carrying portion of a printing device and which nips and carries cut paper.

[0002]

2. Description of the Related Art A conventional paper clamp device for a printing apparatus will be described with reference to FIGS. 4 is a side view showing a schematic mechanism of the printing apparatus, FIG. 5 is a perspective view showing the paper clamping apparatus of FIG. 4, and FIG. 6 is a sectional view taken along line VI-VI of FIG. 7 is the same as FIG. 6 showing the state in which the clamper is opened. In the figure, reference numeral 1 denotes a first pulley, which is provided coaxially with a platen (not shown) on both ends of the platen, and a pair of belts 2 are hung on the pair. A second pulley 3 extends the belt 2 with a third pulley (not shown). Reference numeral 4 is a pinch roller provided so as to be able to come into contact with and separate from the platen, 5 is a paper guide that is a supply path for the paper 6, 7 is a cam, and 8 is a clamper that is installed between the belts 2. Rotate. Reference numeral 9 denotes a back plate, which is normally provided at a position where the clamper 8 and the back plate 9 do not come into contact with each other in opposition to the passage locus of the clamper 8 closest to the cam 7 of the passage locus of the clamper 8.

Reference numeral 10 denotes a clamp bar extending in the width direction of the paper 6, both ends of which are attached to the belt 2. 11
Is a clamp arm whose base end is rotatably attached to the clamp bar 10 via a shaft 12. The paper 6 is sandwiched between the clamp arm 11 and the clamp bar 10, and the clamp arm 11 Rubber 13 is provided as a friction member at the contact portion of the paper 6. 1
Reference numeral 4 is a spring provided on the shaft 12 as a biasing means for biasing the clamp arm 11 in the closing direction, and 15 is rotatably attached to the acting portion 11a of the clamp arm 11 and one end thereof moves along the clamp bar 10. The lever is free, and the other end is pressed by the cam 7 in the direction of the arrow 16 in FIGS. 4 and 6 to act as a lever and open the clamp arm 11 as shown in FIG. 7.
A roller 17 is provided at a contact portion of the lever 15 with the clamp bar 10 for smooth movement of the lever 15 with respect to the clamp bar 10. The clamper 8 includes the clamp bar 10, clamp arm 11, and
The shaft 12, the rubber 13, the spring 14, the lever 15, and the roller 17 are formed.

In the sheet clamp device constructed as described above, the clamper 8 is provided between the back plate 9 and the cam 7.
When the other end of the lever 15 is pressed by the cam 7 in the direction indicated by the arrow 16 in FIGS. 4 and 6, the lever 15 rotates in the clockwise direction in the drawing around the acting portion 11a. To do. As a result, the roller 17 rolls on the clamp bar 10 to the left in the figure, and the lever 15 acts as a lever to lift the acting portion 11a, so that the clamp arm 11 moves against the spring 14 as shown in FIG. It will be released. In this state, when the paper 6 is inserted between the clamp bar 10 and the clamp arm 11 and then the pressing force on the lever 15 is released, the clamp arm 11 is closed by the restoring force of the spring 14 and the lever 15 moves counterclockwise. 4 and 6 by turning
It becomes the state of. Then, the sheet 6 is clamped between the clamp bar 10 and the rubber 13 by the urging force of the spring 14.

As described above, the spring 1 having a predetermined biasing force.
Since the clamp arm 11 is directly urged by 4, it is possible to reliably hold the sheet 6 with a sufficient force while keeping it flat. Further, when the clamp arm 11 is closed, the lever 15 does not exert a force on the clamp arm 11, and the lever 15 is a floating mechanism.
The load of the clamp arm 11 can be uniformly applied to the paper 6. Further, since the lever 15 works as a lever to open and close the clamp arm 11, the opening and closing is smooth. Then, to the contact portion of the lever 15 with the clamp bar 10, the roller 1
Since 7 is provided, the load at the time of operating the lever 15 can be reduced, and the opening becomes smoother.

Both ends of the clamp bar 10 are belt 2
When the other end of the lever 15 is pressed by the rotation of the cam 7, the belt 2 extends slightly, the clamp bar 10 contacts the back plate 9 and receives the pressing force, and the clamp arm 11 Ensure the opening of. Further, the clamp bar 10 is stopped from moving in the direction of the arrow 18 in FIG.
Eliminate the displacement of the insertion position of the paper 6. Spring 1 like this
Even if the urging force of 4 is increased, the support of the back plate 9 can ensure the opening of the clamp arm 11 without burdening the belt 2.

In order to reliably prevent the clamp bar 10 from moving in the direction of the arrow 18 due to the rotational component of the cam 7 of the back plate 9, the clamp bar 10 of the back plate 9 is prevented.
If the coating layer 9a made of a material having a large coefficient of friction (for example, polyurethane) is provided on the contact surface with and, the movement of the clamp bar 10 can be reliably prevented.

[0008]

Since the conventional sheet clamping device is constructed as described above, the coating layer 9a provided on the back plate 9 is used for a long time.
When it is peeled off, the clamper 8 is moved by the rotational component of the cam 7, and the clamp arm 11 and the clamp bar 10 are moved.
There was a problem that the paper 6 was not supplied during that time (paper feed error).

The present invention has been made to solve the above problems, and an object of the present invention is to provide a paper clamp device that can reliably supply paper between a clamp arm and a clamp bar.

[0010]

SUMMARY OF THE INVENTION A sheet clamp device according to the present invention includes a biasing means for biasing a clamp arm that holds a sheet to a clamp bar carried by a belt in a closing direction, and one end of the clamp bar. A lever that is movably provided along the axis of the lever and acts as a lever to open the clamp arm by pressing the other end, and a back plate that supports the pressing force of the contact lever due to the extension of the belt when the lever is pressed. , And a locate pin for pressing the clamp bar against the back plate.

[0011]

According to the present invention, before the cam contacts the lever, the locate pin is slid by the cam to press the clamp bar against the back plate to position the clamper.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a side view showing a schematic mechanism of a printing apparatus,
2 is a perspective view showing the paper clamp device of FIG. 1, and FIG. 3 is a view of FIG. 2 seen from the left. The same or corresponding parts as those of the conventional device are designated by the same reference numerals and the description thereof will be omitted. In the figure, 19 is a recess provided on each end of the clamp bar 10, 20 is a bearing support plate fixed to the back plate 9, 21 is a bearing fixed to the bearing support plate 20,
A locating pin 22 is slidably attached to the bearing 21 and is constantly urged by a spring 23 in a direction to be separated from the clamper 8. A pin pressing cam 24 is provided coaxially with the cam 7.

When the locate pin 22 is provided in this manner, the pin pressing cam 2 is provided before the cam 7 contacts the lever 15.
4 presses the locate pin 22, the tip of the locate pin 22 enters the recess 19 of the clamp bar 10, and the clamp bar 10 is pressed against the back plate 9 to position the clamper 8. Therefore, the rotational component force of the cam 7 of the back plate 9 is increased. It is possible to reliably prevent the clamp bar 10 from moving in the direction of the arrow 18 due to.

[0014]

As described above, according to the present invention, it is possible to reliably supply the paper between the clamp arm and the clamp bar.

[Brief description of drawings]

FIG. 1 is a side view showing a schematic mechanism of a printing apparatus showing an embodiment of the present invention.

FIG. 2 is a perspective view showing the paper clamp device of FIG.

FIG. 3 is a diagram of FIG. 2 viewed from the left.

FIG. 4 is a side view showing a schematic mechanism of a conventional printing apparatus.

5 is a perspective view showing the paper clamp device of FIG. 4. FIG.

6 is a cross-sectional view taken along the line VI-VI of FIG. 5, showing a state in which the clamper is closed.

FIG. 7 is the same view as FIG. 6 showing a state in which the clamper is opened.

[Explanation of symbols]

 2 belt 6 paper 7 cam 8 clamper 9 back plate 9a coating layer 10 clamp bar 11 clamp arm 15 lever 19 recess 20 bearing support plate 21 bearing 22 locate pin 23 spring 24 pin pressing cam

Claims (1)

[Claims] 1. A clamp bar carried by a belt, a clamp arm for sandwiching a sheet between the clamp bar, a biasing means for biasing the clamp arm in a closing direction, and a clamp arm for rotating the clamp arm. A lever that is movably mounted and has one end movably provided along the clamp bar and the other end that is pressed to act as a lever to open the clamp arm and normally contacts the clamp bar. A back plate that abuts against the extension of the belt to support the pressing force of the lever when the lever is pressed, and a slidable locate pin that positions the back plate by pressing the clamp bar. Paper clamp device.