JPS629106Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a paper peeling device that allows printing paper to be unwrapped around a platen by opening the lid of the printer.

In conventional printers, the paper to be printed on (hereinafter referred to as
Just call it paper. ) is wrapped around the platen and printed, the paper remains wrapped around the platen due to the holding force due to the platen's charge, the pressure applied to the platen by the print head, the deformation of the paper, etc. In some cases, a tool or the like was required to remove the wrapped paper.

This invention was developed in consideration of the above points, and provides a paper peeling device for a printer that can release paper wrapped around the platen with a rubber roller that rotates in conjunction with the opening operation of the lid.This invention will be explained below with reference to the drawings, using a thermal printer as an example.

FIG. 1 is a schematic configuration diagram showing an embodiment of this invention.
2A and 2B are enlarged perspective views and partial sectional views of the main parts, and FIGS. 3A and 3B are operation explanatory views.

In Fig. 1, 1 is a housing, 2 is a motor, 3 is a pulley, 4 is a platen, motor 2 and pulley 3,
A belt 5 is hung over the platen 4 as shown. 6 is a thermal head, and 7 is a cassette holder into which a cassette 9 containing a ribbon (printing paper) 8 is inserted, and the ribbon 8 is sandwiched between the platen 4 and the thermal head 6. 10A and 10B are ribbon driving motors. Reference numeral 11 denotes a paper feed tray, 12 a paper guide, and 13 a film attached to one end of the paper guide 12, which reliably guides the paper to a paper holding mechanism to be described later. 14 is a lid, 15 is a gear that rotates around a shaft 16 provided on the lid 14, 17 is a gear that meshes with the gear 15 and rotates around a shaft 18, and 19 meshes with the gear 17 and rotates around a shaft 20. It is a rotating gear. As shown in FIG. 2, the shaft 20 is provided with a rubber roller 21 whose outer periphery contacts the platen 4, and a one-way clutch 22 composed of a bearing that drives the rubber roller 21 and a torque limiter 23 are connected to the locking tool 26A, Can be installed with 26B. The torque limiter 23 is composed of a clutch plate 24 and a spring 25, and is a mechanism for transmitting or not transmitting the rotation of the shaft 20 to the inner cylinder of the one-way clutch 22. Reference numeral 27 denotes a response piece that is driven by the operation of an operation handle (not shown), and is attached to the side surface of the platen 4 with a holding piece 28 . Reference numeral 29 denotes a paper holding mechanism provided in a part of the outer periphery of the platen 4 cut out in the axial direction, and holds the paper together with the platen 4. Note that P indicates paper, and the paper holding mechanism 29 that supports this paper is attached so as not to protrude beyond the outer circumferential line of the cylindrical platen 4.

The friction coefficient between the platen 4 and the paper P is μ ₁ , the friction coefficient between the rubber roller 21 and the paper P is μ ₂ , and the clutch 2
If the friction coefficient between the platen ₄ and the rubber roller 21 when there is no paper P is μ 3 , and the friction coefficient between the platen 4 and the rubber roller 21 when there is no paper P is μ ₄ , then there is a relationship between the four: μ ₁ ≪μ ₂ μ ₃ ≫μ ₄ are doing.

Next, the operations of inserting paper and printing will be explained with reference to FIG.

When the paper P is placed on the paper feed table 11 as shown by the imaginary line and pressed while operating the operation handle (not shown), the paper P is guided to the bottom of the paper holding mechanism 29 by the paper guide 12 and the film 13, and The responsive piece 27 creates a gap between the paper holding mechanism 29 and the platen 4. Therefore, when the paper P is inserted into this gap and the operating force of the operating handle is released, the pressing force of the response piece 27 is also released, the paper P is held by the paper holding mechanism 29 and the platen 4, and the paper P is Insertion is complete.

When printing starts, the platen 4 rotates clockwise as the motor 2 rotates while wrapping the paper P around its outer periphery, and the ribbon 8 is rotated by the motors 10A and 1.
It is driven at 0B, and printing is performed on paper P in response to input to the thermal head 6. At this time, the rubber roller 21
rotates in accordance with the rotation of the platen 4, but no rotational force is transmitted to the shaft 20 via the one-way clutch 22.

The following describes the operation of unwrapping the paper from the platen after printing is completed.

When the lid 14 is opened to take out the paper P as shown in FIG.
The gears 17 and 19 are rotated counterclockwise around the shafts 18 and 19, respectively.
Rotate around 20. As a result, the rubber roller 21 is rotated counterclockwise via the one-way clutch 22. As mentioned above, the friction coefficient μ ₁ between the platen and the paper is smaller than the friction coefficient μ ₂ between the rubber roller and the paper, so the paper P between the platen 4 and the rubber roller 21 is pushed to the platen 4 side by the rotation of the rubber roller 21. Then, the paper P slides, and the paper P is sent out together with the rubber roller 21 on the rubber roller 21 side.

Therefore, as shown in FIG. 3b, the paper P is peeled off from the platen by the opening operation of the lid 14. Note that when there is no paper P between the platen 4 and the rubber roller 21, the friction coefficient μ ₄ between the two becomes smaller than the clutch 2.
The friction coefficient μ of 4 becomes larger than ₃ , the torque limiter 23 works, and the rotation of the shaft 20 is reduced by the rubber roller 21.
will no longer be transmitted. Finally, the user operates the operating handle to release the paper P from the paper holding mechanism 29 and take out the paper P.

When the lid 14 is opened, the lid 14 and the gear 15 rotate clockwise around the shaft 16, and the gear 17 rotates counterclockwise and the gear 19 clockwise rotates around the shaft 1.
Rotate around 8 and 20. However, due to the one-way clutch 22, the rotation of the shaft 20 is controlled by the rubber roller 22.
1 is not transmitted. Therefore, the lid 14 can be closed gently and smoothly with appropriate resistance.

Although the above embodiment has been explained using a thermal printer, the present invention is not limited to a thermal printer. Further, although the one-way clutch is constructed using a bearing, it may also be constructed using a ratchet mechanism or the like. Furthermore, although the torque limiter 23 is constructed from the clutch plate 24 and the spring 25, it may be constructed from only the spring 25 or may have other constructions.

As explained above, the paper peeling device of the printer of this invention rotates the rubber roller via a one-way clutch that is linked with the opening operation of the lid to release the paper wrapped around the platen. The paper wrapped around the platen can be peeled off simply by opening the platen, making it easy to take out the paper. Further, there are advantages in that a suitable resistance can be obtained when closing the lid, and the closing operation of the lid can be performed slowly and smoothly.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing an embodiment of this invention.
2A and 2B are enlarged perspective views and partial sectional views of the main parts, and FIGS. 3A and 3B are operation explanatory views. In the figure, 1 is a housing, 4 is a platen, 6 is a thermal head, 8 is a ribbon, 14 is a lid, 15, 17, 19 are gears, 16, 18, 20 are shafts, 21 is a rubber roller, 22 is a unidirectional 23 is a torque limiter, 26A and 26B are locking devices, 29 is a paper holding mechanism, and P is paper.

Claims (1)

[Scope of utility model registration request] A platen whose friction coefficient with the printing paper is μ ₁ , a rubber roller in contact with the platen and whose friction coefficient μ ₂ with the printing paper satisfies μ ₁ < μ ₂ , and the rotation of the lid of the printer. A drive shaft for transmitting force and a unidirectional clutch mechanism for transmitting the rotational force of the drive shaft to the rubber roller loosely fitted to the drive shaft are provided, and the printing paper wrapped around the platen is A paper peeling device for a printer, characterized in that the paper peeling is performed by the rubber roller that rotates in conjunction with the opening rotational force of the lid.