JP2009034937A - Printing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a printing device which is optimized by matching to a customer's demand while a product cost is being reduced. <P>SOLUTION: A wedge-shaped defected part is formed in the vicinity of the leaf spring fixing end of a front plate as the constituting component of a printing hammer, and the position of the fixing end of the front part of the leaf spring by the front plate is shifted. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a printing apparatus including a dot line printer that performs dot printing using a plurality of printing hammer groups arranged in the digit direction, and more particularly to a hammer mechanism portion thereof.

  A dot line printer, which is a representative printing apparatus that performs dot printing, is a printer that performs printing by reciprocating a hammer mechanism section, in which a printing hammer that performs dot printing is mounted, in the digit direction by a shuttle mechanism section.

FIG. 5 is an enlarged cross-sectional view of the hammer mechanism in the printing apparatus. As shown in the figure, the leaf spring-like printing hammer is configured by attaching a hammer pin 11 to the tip of the leaf spring 10. The leaf spring 10 is fixed to the front yoke 16 together with the adjusting plate 14 by caulking with the front plate 12 at the front and the rear plate 13 at the rear, and fixed to the yoke base 17 with bolts 18. ing. The adjustment plate 14 adjusts the amount of deflection of the leaf spring 10 by an adjustment screw 15.
A comb yoke 22 that holds the printing hammer in the non-printing position extends so as to face the upper back surface of the printing hammer (leaf spring 10), and the base end portion of the comb yoke 22 holds the printing hammer in the non-printing position. It is in contact with the permanent magnet 21 that generates a magnetic attractive force. The comb yoke 22 is provided with a release printing coil 20 for driving a printing hammer.

  The bending energy previously given to the leaf spring 10 is released by the release electromagnetic coil 20, and dot printing is performed on the printing paper 24 via the ink ribbon 23. Printing is sequentially performed by repeating a series of operations until the leaf spring 10 returns to the contact position (non-printing position) with the comb yoke 22 by the return of the magnetic attractive force of the permanent magnet 21.

  In general, the demand for dot line printers can be broadly divided into high-definition printing that requires relatively high dot density, such as kanji and bar code printing, and high-speed draft printing that mainly uses only alphanumeric characters ( In some cases, it is necessary to perform thinning printing by thinning out the character structure within a legible range and making the dot density relatively rough, and it is necessary to optimize the specifications of the dot line printer according to customer requirements.

  As performance required for a printing hammer, for high-definition printing with a relatively high dot density, it is generally necessary to increase the spring constant of a leaf spring in order to increase the response frequency of the printing hammer. However, if the spring constant is increased, it becomes more susceptible to the component accuracy of the component parts, so that there is a problem that high-precision component processing is required and the cost is increased.

  On the other hand, for high-speed draft printing where the dot density is relatively coarse, the response frequency of the printing hammer is generally lower than that for high-definition printing, so it is necessary to increase the spring constant of the leaf spring. No. However, due to the productivity of the component parts, there has been a problem that the cost is increased in the same way as in the case of high-definition printing by sharing with the case of high-definition printing.

  For the printing hammer, in order to stabilize the spring constant even if the spring constant of the leaf spring increases, by providing a rear plate with a groove on the rear fixed end side of the printing hammer, the fixed end of the leaf spring is ensured, There is an example in which deterioration in print quality is prevented (for example, see Patent Document 1 below).

  In addition, by making the shape of the front plate, which is the fixed end of the printing hammer, stepped, the fixed end position of the printing hammer changes depending on the operating distance of the printing hammer, and the spring constant of the leaf spring changes accordingly. There is an example in which the response speed of a hammer is obtained (see, for example, Patent Document 2 below). In this example, the fixed end position where the printing hammer contacts the front plate is changed by bringing the stepped portion of the front plate into contact with the printing hammer.

JP-A-9-70991 JP 2002-240330 A

  As described above, for high-speed draft printing where the dot density is relatively coarse, by sharing the high-definition printing with the convenience of the productivity of the components, the same as in the case of high-definition printing. There was a problem that increased costs. In addition, due to restrictions on the module configuration of the printing hammer, there is a problem that a difference in hammer characteristics due to a structural cause occurs in the printing hammer of a specific digit.

  SUMMARY OF THE INVENTION An object of the present invention is to realize a printing apparatus that eliminates the drawbacks of the prior art and reduces the product cost and is optimized according to customer requirements.

  In order to achieve the above object, the present invention provides a plurality of leaf spring-like printing hammers arranged in parallel at a predetermined pitch in the digit direction and provided with hammer pins for dot printing at the tip, and the printing hammer is fixed, For driving the printing hammer, a front plate in front of the printing hammer and a rear plate behind the printing hammer, which are fixed ends of the spring, a permanent magnet for generating a magnetic attractive force to hold the printing hammer in a non-printing position The present invention is intended for a printing apparatus provided with a hammer mechanism having a release electromagnetic coil that is provided in each printing hammer and is supplied with a predetermined release current to cancel the magnetic field of the permanent magnet.

  The first means of the present invention is characterized in that a wedge-shaped defect portion is provided in the vicinity of the leaf spring fixing end of the front plate, and the fixing end position of the front portion of the leaf spring by the front plate is shifted. is there.

  According to the second means of the present invention, for the printing hammer of a specific digit, a wedge-shaped defect portion is provided in the vicinity of the plate spring fixed end of the front plate, and the fixed end position of the front portion of the plate spring by the front plate is shifted. It is characterized by this.

  The present invention has the above-described configuration, and can provide a printing apparatus that is optimized for customer requirements while reducing product costs.

  Next, embodiments of the present invention will be described with reference to the drawings. 1 is a partial cross-sectional view of the vicinity of a printing hammer according to the embodiment, FIGS. 2 and 3 are perspective views of a front plate and a front yoke, and FIG. 4 is a schematic configuration diagram of the printing apparatus.

  First, an overall schematic configuration of the printing apparatus will be described with reference to FIG. Both ends of the hammer mechanism portion 50 shown in FIG. 5 are slidably supported by linear motion bearings 53, 53, and are reciprocated in the digit direction by the shuttle mechanism portion 51.

  A large number of printing hammers 52 constituted by the leaf springs 10 and the hammer pins 11 shown in FIG. 5 are arranged at a predetermined pitch in the digit direction as shown in FIG. The platen 25 that receives the striking force of each printing hammer 52 is disposed with a predetermined gap so as to face the hammer mechanism 50 via the printing paper 24 and the ink ribbon 23.

  The endless ink ribbon 23 pre-tensioned by the ribbon brake 59 is wound up by a ribbon drive roller 55 via a plurality of ribbon guides 56 and returned to the ribbon cassette 54 again.

  The shuttle mechanism 51 includes a shuttle motor 57 and a crank mechanism 58 that is rotationally driven by the shuttle motor 57, and the hammer mechanism 50 is connected to a part of the crank mechanism 58.

  The configuration of the hammer mechanism 50 is the same as that shown in FIG. The printing paper 24 is sequentially fed out by a paper feeding mechanism (not shown).

  As shown in FIG. 2, the front plate 12 according to the present embodiment is formed by laminating electromagnetic steel plates, and is integrated with the front yoke 16. When the electromagnetic steel plates are progressively pressed, Can be processed in the process.

  The present embodiment is characterized in that a wedge-shaped defect portion 1 is provided in the vicinity of the leaf spring fixed end of the front plate 12, and the fixed end position of the front portion of the leaf spring by the front plate 12 is shifted.

  As shown in FIGS. 1 and 2, a wedge-shaped defect 1 having an angle β, a length c, and a width d is formed near the fixed end of the leaf spring 10 of the front plate 12. Here, in the present embodiment, the angle β is about 3 °, the length c is about 1 mm (the dimension is adjusted to the desired response frequency of the leaf spring 10 within a range where no component interference occurs), and the width d is the leaf spring. The spring width L of 10 is selected so that d> L so as not to interfere with the operation of the leaf spring 10 in the deflection direction.

  The angle β is selected so that β> α with respect to the physical maximum operating angle α of the leaf spring 10. The maximum operating angle α is an angle at which the leaf spring 10 moves forward and eventually interferes with other components, in this embodiment, the front yoke 16. In this embodiment, α is about 2 °.

  Therefore, the wedge-shaped defect portion 1 formed in the vicinity of the fixed end of the leaf spring 10 of the front plate 12 does not always come into contact with the entire operation of the leaf spring 10, and the fixed end of the front portion of the leaf spring by the front plate 12. The position can be shifted. Here, the fixed end of the leaf spring 10 before providing the wedge-shaped defect portion 1 is an e portion, and the fixed end of the leaf spring 10 after providing the wedge-shaped defect portion 1 is an f portion.

  The wedge-shaped defect portion 1 forms a front plate 12 which is integrated with the front yoke 16 and is subjected to progressive pressing as follows. In order to improve the adhesion between the laminated parts subjected to the progressive press processing, it is common to perform a re-pressing (re-caulking) process. Therefore, simultaneously with the re-pressing step, the wedge-shaped defect portion 1 can be formed on the front plate 12 without forming another step. Alternatively, if it is allowed to increase by one process, a molding process may be added and formed separately from the re-pressing process. Therefore, since the basic processing method of the front plate 12 and the front yoke 16 is not changed, the expensive progressive press die is not changed, and a relatively inexpensive re-pressing die is partially changed. And it is convenient for productivity.

  As described above, for high-speed draft printing in which the dot density is relatively coarse as compared with the case of high-definition printing, the response frequency of the printing hammer is generally reduced by the front plate 12 before the leaf spring. By shifting the fixed end position of the part in the direction of increasing the length of the leaf spring and lowering the spring constant of the leaf spring 10, it is less affected by the component accuracy of the component parts, and the product cost is expected to be reduced It is.

  As shown in FIG. 3, a wedge-shaped defective portion 2 is formed in the vicinity of the fixed end of the leaf spring 10 of the front plate 12 for the printing hammer of a specific digit, in this embodiment, the printing hammer at both ends of the module.

  As described above, when there is a difference in hammer characteristics due to a structural cause with respect to a printing hammer of a specific digit in a module, for example, magnetic circuit characteristics due to a gap between adjacent modules, such as printing hammers located at both ends of the module. If the difference in hammer characteristics occurs, the fixed end position of the front portion of the leaf spring by the front plate 12 is shifted in the direction of increasing the length of the leaf spring, thereby reducing the spring constant of the leaf spring 10. Therefore, it is possible to correct the difference in the hammer characteristics of specific digits and reduce the variation of the hammer characteristics, and to reduce the product cost.

  Front dot and front yoke, which are components of a printing hammer, in dot line printers that require high-definition printing such as kanji and bar code printing and high-speed draft printing that mainly requires only alphanumeric characters With the same basic design and processing method, it is possible to optimize the specifications of the dot line printer while reducing the product cost by changing the post-process partly to a hammer specification that meets customer requirements.

1 is a partial cross-sectional view of a printing hammer according to an embodiment of the present invention. It is a perspective view of the front plate and front yoke which concern on embodiment of this invention. It is a perspective view of the front plate and front yoke which concern on embodiment of this invention. 1 is a schematic configuration diagram of an entire printing apparatus. It is an expanded sectional view of the hammer mechanism part of the printer.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 is a wedge-shaped defect | deletion part, 2 is a wedge-shaped defect | deletion part, 10 is a leaf | plate spring, 11 is a hammer pin, 12 is a front plate, 13 is a rear plate, 14 is an adjustment plate, 15 adjustment screw, 16 is a front yoke, yoke Base 17, bolts 18 and 20 are release electromagnetic coils, 21 are permanent magnets, 22 are com yokes, 23 are ink ribbons, 24 is printing paper, 25 is a platen, 50 is a hammer mechanism, 51 is a shuttle mechanism, and 52 is A printing hammer, 53 is a linear bearing, 54 is a ribbon cassette, 55 is a ribbon drive roller, 56 is a ribbon guide, 57 is a shuttle motor, 58 is a crank mechanism, and 59 is a ribbon brake.

Claims (2)

A plurality of leaf spring-shaped printing hammers arranged in parallel at a predetermined pitch in the digit direction and provided with hammer pins that perform dot printing at the tip, and the printing hammer fixed to the front end of the printing hammer that fixes the leaf spring A front plate and a rear plate behind the printing hammer, a permanent magnet that generates a magnetic attraction force to hold the printing hammer in a non-printing position, and each printing hammer for driving the printing hammer, In a printing apparatus comprising a hammer mechanism having a release electromagnetic coil that is supplied with a release current to cancel the magnetic field of the permanent magnet,
A printing apparatus, wherein a wedge-shaped defect portion is provided near a plate spring fixed end of the front plate, and a fixed end position of a front portion of the plate spring by the front plate is shifted.   2. A printing hammer of a specific digit, wherein a wedge-shaped defect portion is provided in the vicinity of a leaf spring fixed end of the front plate, and a fixed end position of the front portion of the leaf spring by the front plate is shifted. Printing device.

Images