JP2007190819A - Printing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a printing device which is excellent in a reliability and life at a low cost. <P>SOLUTION: A comb yoke 14 consists of a layered product of two or more magnetic steel sheets. A notch-like level difference 2 is formed in a pole section 1 side of the comb yoke 14. An adhesive 3 is filled in a space 8 between the pole section 1 side formed by the level difference 2 and the inner wall of a coil bobbin 21, and the comb yoke 14 is adhered and fixed to the inner wall of the coil bobbin 21. <P>COPYRIGHT: (C)2007,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 typical printing apparatus that performs dot printing, is a printer that performs printing by reciprocating a hammer mechanism section, which is mounted with a printing hammer that performs dot printing, in the digit direction by a shuttle mechanism section.

  FIG. 6 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 comb yoke 14 that holds the printing hammer in the non-printing position extends so as to face the upper rear surface of the printing hammer (leaf spring 10), and the base end portion of the comb yoke 14 holds the printing hammer in the non-printing position. In contact with the permanent magnet 13 that generates a magnetic attractive force.

  A coil bobbin 21 is inserted into the pole portion 1 of the comb yoke 14, and a release electromagnetic coil 12 for driving a printing hammer is wound around the coil bobbin 21.

  The bending energy previously given to the leaf spring 10 is released by the release electromagnetic coil 12, and dot printing is performed on the printing paper 16 via the ink ribbon 15. 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 14 by the return of the magnetic attractive force of the permanent magnet 13.

  In the figure, 22 is a yoke base, 23 is a front yoke, 24 is a radiation fin, and 25 is a platen. The comb yoke 14, the permanent magnet 13, the yoke base 22, and the front yoke 23 constitute a magnetic circuit.

  FIG. 7 is a perspective view showing the vicinity of the tip of the comb yoke 14 in the conventional printing apparatus. As shown in the figure, the pole portion 17 of the comb yoke 14 has a tip end portion of a pole portion 17 of a laminated product after press-working electromagnetic steel plates in order to withstand the impact received when the leaf spring 10 is attracted after dot printing. Or the side part 18 near the front-end | tip part was laser-welded, and the lamination was fixed. In the figure, 19 is a welding beat portion of the tip portion 17, and 20 is a welding beat portion of the side surface portion 14.

After that, surface treatment such as nickel plating or chromium plating with higher wear resistance was performed. In order to further improve the wear resistance, as an example of performing a special surface treatment, there is an example in which a composite plating of nickel and polytetrafluoroethylene is performed (for example, see Patent Document 1 below).
JP 2002-67359 A

  However, with only fixing between layers by laser welding as described above, there is a possibility that the fixing strength between layers may vary depending on the state of the fracture surface when the electromagnetic steel sheet is pressed and the penetration state during laser welding. It is difficult to withstand the continuous operation of 1 billion times as the target life.

  Therefore, cracks and cracks are generated in the pole portion 17 that receives an impact directly from the leaf spring 10 by filling and bonding an ultraviolet curable adhesive or the like between the coil bobbin 21 and the comb yoke 14 inserted into the hollow portion thereof. In this structure, fretting wear is prevented between the laminations due to the occurrence of vibration or vibration due to impact, and between the pole portion 17 and the inner wall of the coil bobbin 21.

  For this reason, the manufacturing process is increased, the work is complicated, the production efficiency is lowered, and the cost is increased.

  An object of the present invention is to eliminate such drawbacks of the prior art, and to provide a printing device that is inexpensive, has a long life and is highly reliable.

  In order to achieve the above object, the present invention provides a plurality of leaf spring-shaped printing hammers arranged in parallel at a predetermined pitch in the girder direction, and a permanent magnet that generates a magnetic attractive force to hold the printing hammer in a non-printing position. A magnet, a pole portion extending so as to face the upper back surface of each printing hammer, a comb yoke holding each printing hammer in a non-printing position, and a coil bobbin inserted into the pole portion of the comb yoke; The present invention is intended for a printing apparatus provided with a hammer mechanism having a release electromagnetic coil wound around the coil bobbin and for driving each printing hammer.

  According to a first means of the present invention, the comb yoke is formed of a laminate of a plurality of electromagnetic steel plates, a notch-shaped step is provided on a side of the pole portion of the comb yoke, and the pole portion side surface formed by the step is provided. The space between the inner wall of the coil bobbin is filled with an adhesive such as an ultraviolet curable adhesive, and the comb yoke is bonded and fixed to the inner wall of the coil bobbin.

  According to a second means of the present invention, in the first means, the lateral width A on the base side of the pole part of the laminate constituting the comb yoke is substantially equal to the lateral width on the inner side of the coil bobbin. The notch-shaped steps are provided on both the left and right sides of the pole portion at the tip of the lowermost layer, and the width B of the intermediate layer between the uppermost layer and the lowermost layer of the laminate is narrower than the width A. By inserting the coil bobbin into the pole portion of the comb yoke, a first space is formed between the uppermost layer and the lowermost layer of the laminate and the inner wall of the coil bobbin, and the intermediate layer of the laminate and the inner wall of the coil bobbin A second space portion is formed between the first space portion and the second space portion, and the adhesive is filled from the first space portion to the second space portion. To do.

  The third means of the present invention is characterized in that, in the first means or the second means, tapered tapered surfaces are formed on both left and right side surfaces on the tip side of the pole portion.

  The comb yoke of the present invention can provide a printing apparatus that is inexpensive, has a long life, and is highly reliable, because the lamination fixing of the tip of the pole part can be performed only by bonding without a processing step such as laser welding. .

  Next, embodiments of the present invention will be described with reference to the drawings. 1 is a partial perspective view of a coil bobbin and a comb yoke equipped with an electromagnetic coil according to the embodiment, FIG. 2 is an enlarged perspective view of a main part of the comb yoke, FIG. 3 is a perspective view showing a dimensional relationship of the comb yoke, and FIG. FIG. 5 is a schematic configuration diagram of the entire printing apparatus.

  First, the overall schematic configuration of the printing apparatus will be described with reference to FIG. Both ends of the hammer mechanism 50 shown in FIG. 6 are slidably supported by linear motion bearings 53, 53, and are reciprocated in the digit direction by the shuttle mechanism 51.

  A large number of printing hammers 52 constituted by the leaf springs 10 and the hammer pins 11 shown in FIG. 6 are arranged at a predetermined pitch in the digit direction as shown in FIG. The platen 25 that receives the impact force of each printing hammer 52 is disposed with a predetermined gap so as to face the hammer mechanism 50 via the printing paper 16 and the ink ribbon 15.

  Most of the endless ink ribbon 15 is accommodated in a ribbon cassette 54, and the ink ribbon 15 pre-tensioned by a ribbon brake 59 is wound by a ribbon drive roller 55 via a plurality of ribbon guides 56. The mechanism is taken and returned to the ribbon cassette 54 again.

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

  The configuration of the hammer mechanism 50 is the same as that shown in FIG. The printing paper 16 is sequentially fed out by a paper feeding mechanism (not shown).

  As shown in FIG. 3, the comb yoke 14 is formed by punching and laminating electromagnetic steel plates such as silicon steel plates into a predetermined shape by a pressing process, and has a 10-layer structure in this embodiment. As shown in FIGS. 1 and 4, the longitudinal cross-sectional shape of the coil bobbin 21 to be inserted into the comb yoke 14 is a vertically long rectangle that is almost the same as the longitudinal cross-sectional shape of the comb yoke 14, and the release electromagnetic coil 12 is disposed on the outer periphery thereof. It is wound with a predetermined number of turns. In FIG. 4, the release electromagnetic coil 12 is not shown. As shown in FIGS. 1 and 6, the pole portion 1 of the comb yoke 14 slightly protrudes from the opening of the coil bobbin 21.

  As shown in FIG. 3, the shape of the tip of the pole portion 1 of the comb yoke 14 includes the uppermost layer 5 (first layer) and the lowermost layer 7 (tenth layer) of the laminate, and the intermediate layer 6 (second layer˜ The shape is different from that of the ninth layer. That is, the uppermost layer 5 (first layer) and the lowermost layer 7 (tenth layer) have a width A on the base side of the pole portion 1 that is a minimum tolerance (an intermediate width in the IT basic tolerance) with respect to the inner width of the coil bobbin 21. In other words, the width A of the base side of the pole portion 1 is substantially equal to the width of the inner side of the coil bobbin 21 and the coil bobbin 21 is inserted into the pole portion 1 and does not wobble. Thus, the pole portion 1 is automatically arranged at the center position of the coil bobbin 21.

  Further, a notch-shaped step 2 having a width α is provided on both sides of the pole portion 1, so that the lateral width on the tip side of the pole portion 1 is (A-2α), and is narrowed (thinned) by the width α on both sides. Yes. Therefore, with respect to the uppermost layer 5 (first layer) and the lowermost layer 7 (tenth layer), the first space portion 8 (the right side of FIG. 4) having a lateral width α is provided between the side wall of the pole portion 1 and the inner surface of the coil bobbin 21. Are formed).

  On the other hand, the intermediate layer 6 (second to ninth layers) is not provided with a step 2 like the uppermost layer 5 (first layer) and the lowermost layer 7 (tenth layer), and is narrower than the lateral width A. The horizontal width B of the part 1 is set (A> B). Therefore, on the base side of the pole portion 1 of the intermediate layer 6 (second layer to ninth layer), β [= (A−B) between the first layer and the second layer and between the ninth layer and the tenth layer. / 2] between the side wall of the pole portion 1 of the intermediate layer 6 (second layer to ninth layer) and the inner surface of the coil bobbin 21, the second space portion 9 having a lateral width β (FIG. 4). Are formed respectively).

  Further, as shown in FIG. 3, the length in the longitudinal direction of the uppermost layer 5 (first layer) and the lowermost layer 7 (tenth layer) is the length of the intermediate layer 6 (second layer to ninth layer). It is designed to be slightly shorter than that, and tapered taper surfaces 4 are formed on both side surfaces of the tip.

  In the present embodiment, the number of electromagnetic steel sheets constituting the comb yoke 14 is 10, the thickness is 0.5 mm, the lateral width A is 1.4 mm, the lateral width B is 1.32 mm, the lateral width α is 0.05 mm, and the lateral width β is 0.04 mm.

  As shown in FIG. 1, a coil bobbin 21 around which an electromagnetic coil 12 is wound is inserted into the comb yoke 14. As described above, since the lateral width A of the uppermost layer 5 (first layer) and the lowermost layer 7 (tenth layer) has a minimum tolerance with respect to the lateral width inside the coil bobbin 21, the coil bobbin 21 is inserted into the pole portion 1. Thus, the pole portion 1 is automatically arranged at the center position of the coil bobbin 21. Accordingly, the first space portion 8 and the second space portion 9 formed between the pole portion 1 and the coil bobbin 21 are symmetric in size, and the first space portion 8 and the second space portion 9 are continuous. (See right cross section in FIG. 4).

  From the first space portion 8 to the second space portion 9, an ultraviolet curable adhesive is filled, and by performing a curing treatment by ultraviolet irradiation, the side surfaces of the laminated steel plates constituting the pole portion 1 are covered. Then, an adhesive filling layer 3 is formed between the pole portion 1 and the coil bobbin 21 (see the left cross section in FIG. 4). The adhesive filling layer 3 can be uniformly formed symmetrically from the structure of the comb yoke 14. In the present embodiment, an ultraviolet curable adhesive is used, but other curable adhesives such as an epoxy resin may be used.

  This structure prevents cracking and cracking at the tip of the pole part that receives direct impact from the leaf spring of the printing hammer, or fretting wear between the layers due to vibration caused by the impact, and between the pole part and the coil bobbin inner wall. can do.

  Note that the tip of the pole portion of the comb yoke is subjected to wear-resistant surface treatment, for example, chrome plating, before the coil bobbin is inserted, so as to be resistant to the impact received from the leaf spring of the printing hammer.

  In addition, coil bobbins tend to be deformed so that the vicinity of the center of the coil bobbin side wall is dented due to the effect of tension applied to the coil when winding, and workability when inserting the coil bobbin into the pole part of the comb yoke There is a risk of damage. In this respect, in the present embodiment, since there is a second space formed by the step β at a position corresponding to the vicinity of the center of the coil bobbin side wall, it functions to release the deformation of the coil bobbin side wall. Smooth.

  According to an experiment by the present inventors, α = 0.05 mm and β = 0.04 mm in the structure of the comb yoke, and the adhesive is sufficiently filled and fixed from the formed first space portion to the second space portion. As a result of the continuous operation of 1 billion times as the target life, the operation failure of the printing hammer does not occur, and compared with the conventional technique of laser welding the tip of the pole part, It was confirmed to have reliability.

  Therefore, according to the present invention, it is possible to omit the laser welding processing step performed in the conventional comb yoke structure, and it is possible to improve the working efficiency and reduce the product cost.

  In the above embodiment, the uppermost layer and the lowermost layer of the comb yoke are one layer, but two or more layers are also possible.

It is a partial perspective view of a coil bobbin and a comb yoke equipped with an electromagnetic coil according to an embodiment of the present invention. It is a principal part expansion perspective view of the comb yoke. It is a perspective view which shows the dimensional relationship of the comb yoke. It is sectional drawing of the coil bobbin and a comb yoke. 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. It is a partial perspective view of a comb yoke in a conventional printing apparatus.

Explanation of symbols

  1: pole portion, 2: step, 3: adhesive filling layer, 4: taper surface, 5: comb yoke uppermost layer, 6: comb yoke intermediate layer, 7: comb yoke lowermost layer, 8: first space portion, 9: second Space part, 10: leaf spring, 11: hammer pin, 12: release electromagnetic coil, 13: permanent magnet, 14: comb yoke, 15: ink ribbon, 16: printing paper, 21: coil bobbin, 22: yoke base, 23: front York: 24: Radiating fin, 25: Platen, 50: Hammer mechanism, 51: Shuttle mechanism, 52: Printing hammer, 53: Linear bearing, 54: Ribbon cassette, 55: Ribbon drive roller, 56: Ribbon guide, 57: Shuttle motor, 58: Timing belt, 59: Ribbon brake, A: Width on the base side of the pole portion of the uppermost layer and the lowermost layer, B: Width of the intermediate layer.

Claims (3)

A plurality of leaf spring-shaped printing hammers arranged in parallel at a predetermined pitch in the girder direction;
A permanent magnet that generates a magnetic attractive force to hold the printing hammer in a non-printing position;
A comb yoke having a pole portion extending to face the upper back surface of each printing hammer, and holding each printing hammer in a non-printing position;
A coil bobbin inserted in the pole part of the com yoke;
In a printing apparatus provided with a hammer mechanism having a release electromagnetic coil wound around the coil bobbin and driving each printing hammer,
The comb yoke is formed of a laminate of a plurality of electromagnetic steel plates, and a notch-shaped step is provided on a side surface of the pole portion of the comb yoke, and a space portion between the side surface of the pole portion and the inner wall of the coil bobbin formed by the step. The printing apparatus is characterized in that the comb yoke is bonded and fixed to the inner wall of the coil bobbin. The printing apparatus according to claim 1, wherein a lateral width A on the base side of the pole portion of the uppermost layer and the lowermost layer of the laminate constituting the comb yoke is substantially equal to an inner lateral width of the coil bobbin,
The notch-shaped step is provided on both the left and right sides of the pole portion tip side of the uppermost layer and the lowermost layer,
The width B of the intermediate layer between the uppermost layer and the lowermost layer of the laminate is narrower than the width A,
By inserting the coil bobbin into the pole portion of the comb yoke, a first space is formed between the uppermost layer and the lowermost layer of the laminate and the inner wall of the coil bobbin, and the intermediate layer of the laminate and the inner wall of the coil bobbin A second space is formed between the first space and the second space,
The printing apparatus, wherein the adhesive is filled from the first space portion to the second space portion.   3. The printing apparatus according to claim 1, wherein tapered surfaces are formed on both left and right side surfaces on the tip side of the pole portion.

Images