JPH0952399A - Medium press apparatus for printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a flow, impression, etc., from being formed on a medium by providing an actuator for driving a medium press member to a position of operation and a spring for holding the position of operation of the medium press member and the position of retreat thereof at positions on both sides with a dead point therebetween. SOLUTION: A medium press part 2 at a top end is formed of a rubber member into a sawtooth shape. Further, an upper end of a medium press member 1 is joined to an operation part of an actuator 4 which operates the rotational movement of the medium press member 1. That is, the medium press member 1 is shifted to a position of operation by being moved in the B direction and to a position of retreat by being moved in the C direction. A spring 8 is provided, which holds the position of operation of the medium press member 1 and the position of retreat thereof at positions on both sides with a dead point therebetween. By this method, a flaw, impression, etc., can be prevented from being formed on a medium.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a medium pressing device for holding a print medium inserted in a printer.

[0002]

2. Description of the Related Art A print medium (medium) inserted in a printer
A conventional medium holding device for holding a medium has a medium holding actuator for holding and holding a medium, and a medium guide plate provided to face the medium holding actuator. Is operated so that the medium is sandwiched and held between the medium guide plate and the actuator itself or a member that operates in conjunction with the actuator.

[0003]

SUMMARY OF THE INVENTION The conventional medium pressing device for a printer as described above has a force for pressing and holding the medium,
That is, the force to pull out the held medium is constant,
There is a drawback in that it is not possible to judge the medium in the ejected state after the printing process and the medium in the retracted state in the middle of the printing process by the difference in the pulling force.

In order to make such a judgment, two kinds of medium pressing devices, that is, a medium pressing device having a strong pressing force and a medium pressing device having a weak pressing force are provided, and one of them is selected depending on the situation. Although it is possible to operate one of them, such a means causes an increase in the size of the printer and an increase in the price, so that it cannot be said to be an essential countermeasure.

Further, since the above-described conventional medium pressing device for a printer is of a type in which a medium is sandwiched and fixed between the medium pressing device and the medium guide plate, scratches or dents on the medium are caused by the pressing force of both. There is also a problem that such problems occur.

[0006]

SUMMARY OF THE INVENTION A medium holding device for a printer according to the present invention is a fan-shaped medium holding member having a tip-side medium holding portion formed of a saw-toothed rubber member, and the medium holding member is driven to an operating position. And a spring for holding the operating position and the retracted position of the medium pressing member at positions on both sides of a dead center, and further, the medium pressing member is provided at a position facing the medium pressing member. Is provided with a medium guide plate provided with a groove having a width larger than the thickness of the medium and a depth not contacting the medium pressed by the medium pressing member.

[0007]

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a front view showing an embodiment of the present invention,
2 is a sectional view taken along the line AA of FIG.

In FIG. 1, the medium pressing member 1 is rotatable around a rotation center 3, and the medium pressing portion 2 at the tip (lower end) is made of a rubber member and has a sawtooth shape. There is. The upper end of the medium pressing member 1 is connected to the operating portion of the actuator 4 to drive the rotational movement of the medium pressing member 1, and moves in the arrow B direction to move to the operating position and move in the arrow C direction. To move to the retracted position. The actuator 4 moves the medium pressing member 1 in the arrow B direction by the suction movement, and moves the medium pressing member 1 in the arrow C direction by the return movement. Medium holding member 1
A motion restricting member 5 is provided for restricting the movement in the direction of arrow C. The movement of the medium pressing member 1 in the direction of arrow B is restricted by the operation limit point of the actuator 4.
Below the rotation center 3 of the medium pressing member 1, a spring hook portion 6 is provided.
Is provided, and the other end of the tension coil spring (spring) 8 having one end locked to the spring hook 6 is locked to a fixed spring hook 7 provided obliquely above the rotation center 3. . Therefore, when the medium pressing member 1 moves in the direction of arrow B, the spring holding portion 6 moves to the right side of the line connecting the spring holding portion 7 and the rotation center 3, and when the medium pressing member 1 moves in the direction of arrow C. Moves to the left side of the line connecting the spring hook 7 and the center of rotation 3. That is, the spring 8 is provided on the right side or the left side of the dead center depending on the operating state of the medium pressing member 1.
To act stably.

Below the medium pressing member 1, a medium guide plate 9 is provided.
Is provided, and the print medium (medium) is conveyed between the print medium and the upper medium guide plate 12 provided thereon. As shown in FIG. 2, a groove 1 having a width larger than the thickness of the medium pressing member 1 is provided at a position of the medium guiding plate 9 facing the medium pressing member 1.
0 is provided. The depth of the groove 10 is equal to the depth of the medium pressing member 1
The medium 11 pressed by has a depth that does not come into contact with the bottom surface of the groove 10. Next, the operation of the medium pressing device configured as described above will be described.

In the initial state of the printer, the medium pressing member 1 is at the retracted position (the position moved in the direction of arrow C in FIG.
The position of the reference numeral 1a indicated by the chain double-dashed line), the medium pressing member 1 resists the force of the spring 8 when the medium 4 is inserted and the actuator 4 operates in the waiting state for the printing process. By rotating in the direction of arrow B, the medium pressing portion 2 deforms the medium 11 conveyed between the medium guide plate 9 and the upper medium guide plate 12 and pushes it into the groove 10. The printing operation is performed in this state, and the medium 11 is conveyed inside the printer while being partially pushed into the groove 10. However, the shape of the portion of the medium pressing portion 2 that contacts the medium 11 is sawtooth. The medium 11 is conveyed without being subjected to a great resistance because of the shape. When a part of the medium 11 is pushed into the groove 10, the width of the groove 10 larger than the thickness of the medium pressing member 1 is larger than the thickness of the medium pressing member 1, and the depth of the groove 10 is larger than that of the medium 11. Since the depth is such that it does not come into contact and the medium pressing portion 2 is formed of a rubber member,
It does not cause scratches or indentations on the medium.

When the printing operation is completed, the medium 11 is ejected. At this time, the serrated portion of the medium pressing portion 2 is the medium 1.
Since the medium 11 is brought into contact with 1 and a large frictional force is applied to the medium 11, the ejected medium 11 rotates the medium pressing member 1 in the direction of arrow C against the force of the spring 8 and moves to the position of reference numeral 1a. Move to. The medium 11 is subsequently ejected to a predetermined position.

When the ejection of the medium 11 is completed, the actuator 4 is operated again, the medium pressing member 1 is rotated in the direction of the arrow B, and the medium pressing portion 2 presses and holds the medium 11. If you try to pull out the medium 11 by hand in this state,
Since there is a large resistance force to the medium 11 due to the suction force of the actuator 4, it cannot be easily pulled out.
When the suction force of the actuator 4 is cut off, the medium pressing member 1 can be easily rotated in the arrow C direction, so that the medium 11 can be pulled out with a small force.

[0014]

As described above, the medium holding device for a printer of the present invention has a fan-shaped medium holding member in which the medium holding portion at the leading end is formed of a sawtooth rubber member, and the medium holding member is set to the operating position. An actuator that drives the medium holding member and springs that hold the operating position and the retracted position of the medium holding member at positions on both sides of the dead center are provided, and at a position facing the medium holding member, a width larger than the thickness of the medium holding member. And a medium guiding plate provided with a groove having a depth that does not come into contact with the medium pressed by the medium pressing member. There is an effect that it is possible to easily judge the medium in the retracted state based on the difference in the pulling-out force, and further there is an effect that it is possible to prevent the medium from being scratched or indented.

[Brief description of drawings]

FIG. 1 is a front view showing an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

[Explanation of symbols]

 1 Medium Pressing Member 2 Medium Pressing Part 3 Rotation Center 4 Actuator 5 Operation Restricting Member 6 Spring Hooking Part 7 Spring Hooking Part 8 Tension Coil Spring (Spring) 9 Medium Guide Plate 10 Groove 11 Medium 12 Upper Medium Guide Plate

Claims (2)

[Claims] 1. A fan-shaped medium pressing member having a saw-toothed rubber member at the tip of the medium pressing portion, an actuator for driving the medium pressing member to an operating position, and an operating position and a retracting position of the medium pressing member. A medium holding device for a printer, comprising: springs for holding and at positions on both sides of a dead point. 2. A medium guide plate provided with a groove having a width larger than the thickness of the medium pressing member and a depth not contacting the medium pressed by the medium pressing member, at a position facing the medium pressing member. A medium pressing device for a printer according to claim 1, wherein: