JPH0752122Y2 - Roller contact / separation mechanism - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a contact / separation mechanism for a platen roller in a mechanism for detecting a detection object such as a paper sheet by a platen roller against a sensor such as light or magnetism.

(Prior Art) In order to press the detection object against the sensor, the third
As shown in the figure, the platen roller 12 is arranged on the sensor 11, the platen roller 12 is rotatably held by a link 14 which is rotatable around a fulcrum 13, and the link 14 is rotated by a spring 15. Biases the platen roller 12 toward the sensor 11,
A detection object 16 such as a paper sheet is supplied between the sensor 11 and the platen roller 12.

Alternatively, as shown in FIG. 4, the link 14 is connected to the plunger 19 of the solenoid 18 through the connecting link 17, and the solenoid 18 is urged to press the platen roller 12 against the sensor 11 as shown in FIG. 4B. To do. When the urging of the solenoid 18 is released, the return spring 21 causes the plunger 19 to project as shown in FIG. 4A.

Alternatively, as shown in FIG. 5, the link 14 is connected to the plunger 19 of the solenoid 18 via the spring 15, and the detection object 16 is inserted into the non-energized state as shown in FIG. 5A before the detection object 16 is inserted. After the insertion of 16 is facilitated, the solenoid 18 is urged to press the platen roller 12 against the sensor 11 with sufficient force after insertion as shown in FIG. 5B.

(Problems to be Solved by the Invention) When the platen roller 12 shown in FIG. It causes the problem of shortening the life of the. In addition, it may not be possible to pass between the sensor 11 and the platen roller 12 with a weak detection object such as paper.

Using the solenoid 18 shown in FIG. 4, the platen roller
In the case of urging 12, the pressing force was too strong to follow the change in the thickness of the detection object 16 and accurate detection could not be performed, and the passage was obstructed with a weak paper such as paper.

When the platen roller 12 is pressed against the sensor 11 by the solenoid 18 via the spring 15 shown in FIG. 5, the stroke of the plunger 19 of the solenoid 18 for contacting and separating becomes long, and the platen roller 12 is not deformed or deformed. The problem of shortening the life of the sensor 11 was only alleviated.

(Means for Solving the Problem) According to the present invention, the platen roller is rotatably held at one end of the first link rotatably provided with the intermediate portion as a fulcrum, and the other end of the first link is rotatably supported. A pin is set on. A second link is provided movably in a direction substantially at right angles to the line connecting the pin and the platen roller, and the pin is inserted into the notch of the second link. A plunger of a solenoid is connected to the second link so that the solenoid can move the second link. The first spring is connected between the pin and the second link, and the first link is rotationally biased in the direction in which the platen roller contacts the sensor. The second spring is connected to the second link and is biased in the direction of pulling out the plunger.

The second link is moved by the second spring while the solenoid is not energized, the notch end of the second link engages with the pin, the first link is rotated, and the platen roller separates from the sensor. The plunger retracts in the energized state, and the second
The link moves against the second spring and the first spring causes the first
The link rotates to press the platen roller against the sensor, the pin and the end of the notch are separated, and the platen roller is biased to the sensor only by the first spring.

(Embodiment) FIGS. 1 and 2 show an embodiment of the present invention. A first link 14 is rotatably provided around the shaft 13. First link
A platen roller 12 is rotatably held at one end of 14,
A pin 22 is set up at the other end of the first link 14. A second link 23 is provided so as to be movable substantially at right angles to the line connecting the platen roller 12 and the pin 22, and a notch 24 is formed at one end of the second link 23 in the moving direction, and the pin 22 is provided in the notch 24. Is located. A plunger 19 of a solenoid 18 is connected to the other end of the second link 23, and the solenoid 18 allows the second link 23 to move.
Will be moved. The first spring 15 is connected between the pin 22 and the cut-and-raised piece 25 of the second link 23 on the plunger 19 side.
The first link 14 is rotatably biased by 15 so that the platen roller 12 approaches the sensor 11. A second spring 26 is connected between the second link 23 and the fixed portion, and the second spring 26 biases the second link 23 in the direction in which the plunger 19 is pulled out.

When the solenoid 18 is not energized, the second spring 23 pulls the second link 23 to pull the plunger 19 as shown in FIG. 2A.
Is pulled out, the right end of the notch 24 is engaged with the pin 22 by the movement of the second link 23 to the left in the figure, the first link 14 is rotated counterclockwise, and the platen roller 12 is separated from the sensor 11. There is.

When the detection object 16 is sent to the sensor 11, the solenoid 18 is urged, the plunger 19 is attracted and the second link 23 moves to the right as shown in FIG.
The link 14 is rotated clockwise, and the platen roller 12 comes into pressure contact with the sensor 11. At this time, the movement of the second link 23 is larger than the movement of the pin 22 to the right, the pin 22 is separated from the right end of the notch 24, and the platen roller 12 is attached to the sensor 11 only by the force of the first spring 15. Energized.

As described above, according to the present invention, the platen roller 12 is separated from the sensor 11 when the detection object 16 is not supplied, and the platen roller 12 can be pressed against the sensor 11 if necessary. Moreover, since the pressure contact is performed only by the force of the first spring 15, the pressing force of the platen roller 12 that can follow the change in the thickness of the detection object 16 can be obtained. As a result, the platen roller 12 is not deformed, the sensor 11 and the platen roller 12 have a long life, and accurate detection is possible.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention, FIG. 2 is a side view showing the platen roller in a non-contact state (A) and a contact state (B), and FIGS. It is a side view which shows the outline of a mechanism.

Claims (1)

[Scope of utility model registration request] 1. A mechanism for contacting and separating a platen roller with respect to a sensor, wherein the platen roller is rotatably provided with an intermediate portion as a fulcrum, the platen roller is rotatably held at one end, and a pin is provided at the other end. And a second link having a notch in which the pin is inserted, the second link being provided so as to be movable substantially at right angles to the line connecting the pin and the platen roller. A solenoid that drives a second link in its movable direction and a plunger that is connected to the first link in a direction in which the platen roller contacts the sensor, and is connected between the pin and the second link. There is a first spring that biases the link to rotate, and a second spring that biases the second link in the direction in which the plunger is pulled out. The second link moves, the notch end of the second link engages with the pin, the first link is rotated, the platen roller is separated from the sensor, and the plunger is pushed by the solenoid in a biased state. , The second link moves against the second spring, the first link rotates by the first spring, the platen roller presses against the sensor, and the pin and the end of the notch Contact and separation mechanism for rollers that separate from each other.