JPH01192582A - Mechanism for opening/closing paper presser lever - Google Patents

Abstract

PURPOSE:To hold a paper presser assembly constantly stably, by opening/closing a paper presser lever assembly holding the paper presser assembly using a motor for feeding a printing paper. CONSTITUTION:Usually, a paper presser shaft 8 is depressed down against a platen 3 by springs 9, 10 to be held stably. A gear 14 is disengaged from a gear 15 by a spring 21, whereby a lever 11 fails to act even if a platen gear 3a rotates. The electric conduction to a solenoid causes a trigger board 18 to be attracted, thereby moving the gear 14 along a guide groove 18a to a position on which it can engage with the gear 15. The drive force of a paper feed motor is transmitted to the gear 15 and a gear 16, but the gear 16 only rotates without engagement. The gear 15 rotates the lever 11 in a direction A so that a guide surface 11a comes into contact with a shaft 12, and rotates a lever 6 until a part 6a thereof comes into contact with a projected part 1a of a frame. At this time, the electric conduction to the solenoid is cut, and the paper presser shaft 8 is held stably. On the contrary, the travel in a direction B reverses the situations of the gear 15 and the gear 16.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a paper presser lever opening/closing mechanism used in a paper feeding device of a printer.

[Conventional technology]

In the conventional technique, as shown in FIG. 7, a large solenoid 102 is directly engaged with a paper presser assembly 103, 104, 105, and its suction force moves the paper presser shaft 104 to the printing paper retraction position. I was letting it happen.

[Problem to be solved by the invention]

However, in the conventional paper presser lever opening/closing mechanism, the solenoid directly opens and closes the paper presser assembly, so when the printer is turned off, the solenoid is not energized, so the printing paper set has to adjust the position of the printing paper. At the same time,
The operator had to hold the paper presser assembly at the printing paper retraction position C. Furthermore, since the paper presser assembly has to travel a long distance, the solenoid is also large and the cost is high.

Therefore, in order to solve these conventional problems, the present invention stably holds the paper presser assembly in both the position where the printing paper is pressed against the platen and the position where the printing paper is pulled in, and it is possible to use inexpensive paper. The object of the present invention is to provide a presser lever opening/closing mechanism.

[Means to solve the problem]

In order to solve the above problems, the paper presser opening/closing mechanism of the present invention has the following features:
The present invention is characterized in that a spring is provided to hold the paper presser assembly in a bistable manner, and the opening and closing of the paper presser lever assembly is performed by a motor for moving the printing paper.

[Effect]

When the power of the printer is turned off, the paper presser lever opening/closing mechanism configured as described above is disconnected from the motor means for moving the printing paper. It can be held in any stable position. Further, when the printer is in use, by energizing the solenoid, the paper presser lever assembly can be moved to one of the two stable positions by the driving force of the motor means.

〔Example〕

Embodiments of the present invention will be described below based on the drawings. 1 to 5 show a first embodiment, and FIG. 6 shows a second embodiment.

1 is a front view, FIG. 2 is a side view, and FIG. 3 is a view of the frame 17 from the back side. Paper presser levers 6.7 rotatably supported on shafts 4.5 on the frame 1.2 on both sides of the printer support both ends of the paper presser shaft 8, respectively.

The paper presser lever 6.7 is moved by a spring 9.10 to the platen 3.
The position where the paper presser shaft 8 is pressed and the paper presser lever 6
The zero wavy line portion 6a is held in a stable state at a position where it is pressed against the convex portion 1a on the frame 1 (the same applies to the frame 2). A paper feed motor (not shown) transmits driving force through its gear train, and finally rotates a gear 3a fixed to the platen 3 to move the printing paper onto the platen 3. A gear 14 is slidably held on the frame 17 by a guide groove 17a, and gears 15 and 16 are rotatably supported. A trigger plate made of metal is rotatably supported on a frame 17 by a shaft 19, and holds the gear 14 from both sides by grooves 18a. The trigger plate 16 is held by a spring 21 in a position where the gear 14 and the platen gear 3a are out of mesh according to the guide groove 17a of the frame. When the solenoid 20 fixed to the back side of the frame 17 is energized, the trigger plate 1
8, thereby causing the gear 14 and the platen gear 3a to
, mesh with the gear 15 to transmit the driving force of the paper feed motor.

The lever 11 is provided with guide surfaces 11a and 11b of the shaft 12 fixed to the paper presser lever 6, and teeth 11c and lid that mesh with teeth 15a and 16a provided on the gear 15.16, The concentric portions of the teeth 11c and 11°d are rotatably supported on the frame 1 by screws 13.

Next, the operation will be explained in detail with reference to FIGS. 4 and 5.

Normally, the paper presser shaft 8 is stably held against the platen 3 by being pressed against the spring 9.10. The gear 14 is kept out of mesh with the gear 15 by the spring 21, and the platen gear 3a
Even if the lever 11 is rotating, the lever 11 does not perform any operation.

However, when the solenoid 20 is energized, the trigger plate 18 overcomes the spring 21 and is attracted, moving the gear 14 along the guide groove 18a to a position where it meshes with the gear 15. The driving force of the paper feed motor is transmitted to the gears 15 and 16, but since there are no teeth that mesh with the teeth lid of the gear 16 and lever, they simply rotate. However, the gear 15 has the gear 15a meshing with the toothed part 11c of the lever, and the lever 11 is
Rotate in the direction. Therefore, the guide surface 11a comes into contact with the shaft 12, and the lever 6 is rotated in the direction A until the part 6a of the paper presser lever comes into contact with the convex portion 1a of the frame. At this point, the gear 15a has no teeth and is no longer in mesh with the lever teeth 11c, and the solenoid is also turned off. Therefore, the paper presser shaft 8 is stably held again at this position. Next, FIG. 5 is a diagram showing movement in the direction B in the opposite direction.

In this case, the positions of gear 15 and gear 16 are reversed.

Next, a second embodiment is shown in FIG. In addition to the first embodiment, a lever 30 is fixed to the gear 15, and a spring 31 is attached to the lever 30. Therefore, when the driving force of the paper feed motor is not transmitted, the spring 3 is applied to the gears 15 and 16.
1 through the lever 30, and the toothed portion 15a or the toothed portion 16a is pressed against the toothed portion 11c or the toothed portion lid, respectively.
When one of the two is always in mesh with the other and the solenoid 20 is energized, the operation is more reliable than in the first embodiment.

〔Effect of the invention〕

As explained above, the paper presser lever opening/closing mechanism of the present invention utilizes the driving force of the paper feed motor, is composed of a small trigger solenoid and a plurality of gears, and is always in a position where the paper presser assembly is pressed against the platen. This has the effect of stably holding the printing paper in either position where it is pulled in and reducing costs.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing a first embodiment of the present invention. FIGS. 2 to 5 are cross-sectional views showing the first embodiment. FIG. 6 is a diagram showing a second embodiment. FIG. 7 is a sectional view showing a conventional embodiment. 1.2...Frame 3.101...Platen 6.7.103...Paper presser lever 8.104...Paper presser shaft 13a, 14.15.16...gear 17...Frame 20.102... Solenoid that's all Applicant: Seiko Epson Corporation Figure 1 Figure 2 Figure 3 Figure 5 Figure 6 Figure 7

Claims (2)

[Claims] (1) A paper presser shaft that presses the printing paper on the platen, and a pair of pivoted paper presser levers that support the paper presser shaft;
The paper presser shaft is arranged so as to be stable in two positions: a first position where the paper presser shaft presses the printing paper against the platen, and a second position where the print paper is pulled in, and the paper presser shaft presses the printing paper through the paper presser shaft. A paper presser lever assembly consisting of a first spring member that presses the paper, a motor means for moving the printing paper, a first gear that transmits the driving force of the motor means, and the paper presser lever assembly. a pivotally supported lever member having a guide portion for moving the lever member to two stable positions and having a gear portion; a gear portion that meshes only when the lever member is rotated only on one side; and the first gear. a second gear having a gear part that meshes with the second gear; a gear part that meshes with the second gear; and a third gear having a gear part that meshes only when the lever member is rotated in the other direction. , a metal member that holds the first gear, a solenoid that moves the first gear to a position where it meshes with the second gear by suctioning the metal member, and the metal member and a second spring member that engages with and holds the first gear in a position where it is out of mesh with the second gear. (2) The paper presser lever opening/closing mechanism according to item 1, further comprising a spring member that biases the second gear or the third gear in the rotational direction.