JP2002211054A - Printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a printer which is used for a portable terminal device wherein a conveyance roller is surely held and is readily attached to or detached from the printer. SOLUTION: The cylindrical conveyance roller 10 having a reduction mechanism formed on the internal periphery thereof and a motor 4 engaged with the reduction mechanism are integrally supported to a roller frame 12 and the roller frame 12 is detachably attached to a base frame 21 having a print head 6 which is brought into contact with the conveyance roller 10 by a prescribed pressing force. A lock pawl 23 for stopping the roller frame 12 is provided to the base frame 21. As a result of the above structure, it is possible to provide the printer wherein the conveyance roller can be surely supported and the attaching or detaching of the conveyance roller can be readily executed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing apparatus which is incorporated in a printer such as a portable terminal device and performs printing while conveying a printing sheet.

[0002]

2. Description of the Related Art In recent years, printers have been increasingly used by being incorporated into portable terminal equipment and the like, and a printing device used in such printers has also been required to have easy operability and improved reliability.

In a conventional printing apparatus, a conveying roller for conveying a print sheet is connected to a motor arranged in parallel with the conveying roller via a plurality of reduction gears. It is constituted so that it may be pressed.

FIG. 5 shows such a conventional printing apparatus.
This will be described with reference to FIG.

FIG. 5 is an exploded perspective view of a conventional printing apparatus. In FIG. 5, reference numeral 1 denotes a cylindrical conveying roller having a driving gear 2 fixed at one end, and left and right shaft portions 1 A and 1 B of a frame 3. It is rotatably and detachably supported by the holding parts 3A and 3B.

A motor 4 arranged in parallel with the transport roller 1 is mounted on the frame 3, and a plurality of reduction gears 5 meshing with the driving gear 2 are rotatably mounted.

Reference numeral 6 denotes a print head. The print head 6 is pressed against the conveying roller 1 with a predetermined pressing force by a pressing means 7 such as a spring to constitute a printing apparatus.

In a state where such a printing apparatus is incorporated in a device as a printer, the conveying roller 1 projects from a lower surface of an opening / closing door (not shown) of the device in order to prevent the transport roller 1 from coming off the frame 3 upward. Provided attachments, etc.
The shafts 1A and 1B are brought into contact with each other so that they can rotate,
Built into equipment.

In the above configuration, when the motor 4 is rotated, the rotation is transmitted to the transport roller 1 via the plurality of reduction gears 5 and is brought into pressure contact with the transport roller 1 as the transport roller 1 rotates. The print sheet 8 disposed between the print head 6 and the print head 6 is conveyed, and at the same time, the print head 6 is energized.
Is configured to perform printing of characters and the like.

Further, when the printing sheet 8 is exchanged or fed, when the opening / closing door of the apparatus is opened, the above-mentioned attachments are separated from the shaft portions 1A and 1B of the transport roller 1, and the transport roller 1 is moved to the frame. 3, the print sheet 8 can be easily replaced.

[0011]

However, in the above-mentioned conventional printing apparatus, an attachment for rotatably holding the transport roller 1 on an opening / closing door of the apparatus or the like is provided in order to prevent the transport roller 1 from coming off the frame 3. When the transport roller 1 is attached to and detached from the frame 3 such as when the printing sheet 8 is replaced, a force is applied to the drive gear 2 of the transport roller 1 and the plurality of reduction gears 5 meshing therewith, and the gear is damaged. There is a problem that is easy to occur.

An object of the present invention is to solve such a conventional problem, and an object of the present invention is to provide a printing apparatus which can securely hold a transport roller and can be easily attached and detached.

[0013]

To achieve the above object, the present invention has the following arrangement.

According to the first aspect of the present invention, a cylindrical conveyance roller having a speed reduction mechanism formed on an inner periphery thereof and a motor meshing with the speed reduction mechanism are integrally supported on a roller frame, and a predetermined speed is provided on the conveyance roller. This roller frame is detachably held on a base frame equipped with a print head that is pressed against the pressing force, and a lock claw that locks the roller frame is provided on the base frame to constitute a printing device.
Since the transport roller, the reduction mechanism and the motor are integrated into the roller frame, the gear can be prevented from being damaged when the transport roller is attached and detached, and the transport roller is securely held by the lock claws, making it easy to attach and detach. Is obtained.

According to a second aspect of the present invention, in the first aspect of the present invention, the lock claw is provided with an interference portion for pressing the mounting plate during rotation or movement, and the interference portion is provided when the lock claw is released. Presses the mounting plate and eliminates pressure contact of the print head with the transport roller, so that the transport roller can be easily attached and detached when replacing a print sheet or feeding paper.

According to a third aspect of the present invention, in the first aspect of the invention, at least one of the roller frame and the base frame is fixed by a fixing member, or a guide portion for restricting the rotation of the roller frame is provided on the base frame. In the case where it is not necessary to remove the transport roller, there is an effect that unnecessary rotation of the roller frame during rotation of the transport roller can be prevented.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

The same components as those described in the section of the related art are denoted by the same reference numerals, and detailed description thereof will be omitted.

(Embodiment) FIG. 1 is a sectional view of a printing apparatus according to an embodiment of the present invention, and FIG. 2 is an exploded perspective view of the printer. In FIG. The outer peripheral surface of the large diameter portion 10A is covered with an elastic material 10B such as silicon rubber, and the small diameter portion 10C is fitted with the bearing 11 The roller frame 12 is rotatably supported.

A rotary internal gear 13 is formed on the inner periphery of the transport roller 10, and the outer side of a planetary gear 14 A rotatably supported by a carrier 15 meshes with the rotary internal gear 13. .

Reference numeral 16 denotes a fixed internal gear arranged coaxially with the rotary internal gear 13. The outer peripheral surface has a convex portion 16A sliding on the inner peripheral surface of the conveying roller 10 and a polygonal flat surface. The rotation suppressing portion 16B has an inner peripheral surface having a number of teeth different from that of the rotating internal gear 13 in the transport roller 10, and meshing with the outside of a planetary gear 14B rotatably supported by the carrier 15. A gear 16C is formed.

Reference numeral 4 denotes a motor, which is mounted on the roller frame 12 coaxially with the conveying roller 10 together with the cylindrical member 17, and a sun gear 18 fixed to the rotating shaft of the motor 4 has a central hole 15A of the carrier 15. And meshes with the inside of two planetary gears 14A and 14B rotatably supported at predetermined intervals by the carrier 15.

Reference numeral 19 denotes a regulating member having one end fixed to the roller frame 12, and a resilient member 19A at the other end having a polygonal rotation suppressing portion 16B provided on the outer peripheral surface of the fixed internal gear 16.
Is pressed.

As described above, the reduction mechanism including the rotating internal gear 13, the planetary gears 14 A and 14 B, and the fixed internal gear 16 is formed on the inner periphery of the cylindrical transport roller 10. 12 is rotatably supported, and the motor 4 in which the sun gear 18 meshing with the reduction mechanism is fixed to the rotation shaft is also fixed to the roller frame 12,
These are integrated to form a platen block 20.

Reference numeral 21 denotes a substantially U-shaped base frame having a bottom plate and side plates rising upward from both sides thereof.
0 is detachably held.

Reference numeral 6 denotes a print head. The print head 6 is mounted on the base frame 21 together with the mounting plate 22 and is pressed against the mounting plate 22 by pressing means 7 such as a spring. Is pressed with a predetermined pressing force.

Reference numeral 23 denotes a lock claw rotatably mounted on the side plate of the base frame 21. The lock claw 23 is urged in the front locking direction by a spring member 24 so that the locking portion 23A is engaged with the engaging portion 12A of the roller frame 12. Locked, the platen block 20 is held by the base frame 21 to form a printing device.

In the above-described configuration, when the motor 4 is energized to rotate the sun gear 18, the planetary gears 14A, 14B
Revolves, and a gap occurs between the rotating internal gear 13 and the fixed internal gear 16 having different numbers of teeth.

At this time, the fixed internal gear 16 is
Since the rotation is stopped by the rotation suppressing portion 16B pressed by the elastic member 19A of No. 9, the transport roller 10 provided with the rotating internal gear 13 is rotated at a reduced speed.

As shown in the external perspective view of FIG. 3, the belt-shaped print sheet 8 disposed between the print heads 6 is conveyed by the rotation of the conveyance roller 10 against which the print heads 6 are pressed, and at the same time, the print heads 6 are energized. Is performed, characters and the like are printed on the print sheet 8, and information recording is performed in the same manner as in the related art.

When the printing sheet 8 is exchanged or fed, the opening and closing door (not shown) of the apparatus is opened and the transport roller 10 is removed in the same manner as in the prior art.
There is no need to provide an attachment or the like on the lower surface of the opening / closing door, etc.
Since the reference numeral 0 is held on the base frame 21 by the lock claws 23, the transport rollers 10 can be easily attached and detached by removing the lock claws 23.

As described above, according to the present embodiment, the platen block 20 in which the transport roller 10 is integrated is held detachably on the base frame 21 by the lock claw 23, so that the transport roller 10 is securely held. And a printing device in which the transport roller 10 can be easily attached and detached when the print sheet 8 is replaced.

The rotating internal gear 13 and the planetary gear 14
A reduction mechanism comprising A, 14B and a fixed internal gear 16 is formed on the inner periphery of the cylindrical transport roller 10, and the transport roller 10 and the motor 4 are fixed to the roller frame 12 and integrally formed as a platen block 20. Has been
It is also possible to prevent the gears from being damaged due to a collision between the gears when the transport roller 10 is attached or detached.

Further, as shown in FIG.
Is provided with an interference portion 23B that presses the pressing portion 22A of the mounting plate 22 during rotation or movement. When the lock claw 23 is released, the interference portion 23B presses the mounting plate 22 so that the transport roller of the print head 6 Since there is no pressure contact with the transfer roller 10, the transfer roller 10 can be more easily attached and detached when the print sheet 8 is exchanged or fed.

In the above description, the lock claw 23 is provided only on the right side plate of the base frame 21.
Further, the present invention can be implemented even if the left and right lock claws 23 are connected by a shaft or the like and the two lock claws 23 are interlocked by one operation.

Furthermore, the lock claw 23 has been described as being biased in the front locking direction by the spring member 24. However, the spring member 24 may be provided integrally with the lock claw 23, or may be attached without using the spring member 24. It is also possible to use the urging force of the pressing means 7 for pressing the plate 22.

In the above description, the transport roller 10 is removed when the print sheet 8 is exchanged or fed, but when it is not necessary, as shown in an exploded perspective view of FIG. In addition, a guide portion 21A for restricting the rotation of the roller frame 12 by contacting the left end face of the roller frame 12 is provided on the left side plate of the base frame 21, or through holes 21B, 1
2B is provided, and a fixing member 27 such as a screw is inserted thereinto,
By fixing the base frame 21 and the roller frame 12, unnecessary rotation of the platen block 20, such as when the transport roller 10 is rotated, can be prevented.

At this time, as described above, the interference portion 2 pressing the pressing portion 22A of the mounting plate 22 against the lock claw 23 is used.
By providing the 3B, the interference portion 23B presses the mounting plate 22 when the lock claw 23 is released, and the press contact of the print head 6 with the transport roller 10 is eliminated, so that the printing sheet 8 can be easily replaced or fed. Can be done.

[0039]

As described above, according to the present invention, there is obtained an advantageous effect that it is possible to obtain a printing apparatus which can securely hold the transport roller and can be easily attached and detached.

[Brief description of the drawings]

FIG. 1 is a sectional view of a printing apparatus according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view of the same.

FIG. 3 is an external perspective view of the same.

FIG. 4 is an exploded perspective view according to another embodiment.

FIG. 5 is an exploded perspective view of a conventional printing device.

[Explanation of symbols]

 Reference Signs List 4 Motor 6 Print head 7 Pressing means 10 Conveying roller 10A Large diameter portion 10B Elastic material 10C Small diameter portion 11 Bearing 12 Roller frame 12A Engaging portion 12B, 21B Through hole 13 Rotating internal gear 14A, 14B Planetary gear 15 Carrier 15A Central hole DESCRIPTION OF SYMBOLS 16 Fixed internal gear 16A Convex part 16B Rotation suppression part 16C Internal gear part 17 Cylindrical member 18 Sun gear 19 Restriction member 19A Elastic member 20 Platen block 21 Base frame 21A Guide part 22 Mounting plate 22A Press part 23 Lock claw 23A Stop part 23B Interference part 24 Spring member 27 Fixing member

Continuing on the front page (72) Inventor Masaaki Matsui 1006 Kazuma Kadoma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. 2C058 AB05 AC07 AE02 AE03 AE04 AE09 AF31 BA08 BA09 3F049 AA10 DA14 LA07 LB01

Claims (3)

[Claims] 1. A cylindrical conveyance roller having a reduction mechanism formed of a plurality of gears formed on an inner periphery thereof, a motor having a sun gear fixed to a rotation shaft meshing with the reduction mechanism, and a rotatable conveyance roller. And a roller frame for fixing the motor coaxially with the conveying roller, and a print head for holding the roller frame detachably and pressing the mounting plate and pressing against the conveying roller with a predetermined pressing force. And a lock claw that locks the roller frame provided on the base frame. 2. The printing apparatus according to claim 1, wherein the locking claw is provided with an interference portion that presses the mounting plate during rotation or movement. 3. The printing apparatus according to claim 1, wherein at least one of the roller frame and the base frame is fixed by a fixing member, or the base frame is provided with a guide portion for regulating the rotation of the roller frame.