JPH0558315U - Print head for dot impact printer - Google Patents

Abstract

(57) [Abstract] [Purpose] It is possible to reduce the propagation of vibration by suppressing the variation of the compression force of the anti-vibration rubber and the parallelism between the frame member and the nose portion, and to prevent the deterioration of the print quality. To provide a print head for a dot impact printer. [Structure] A plate member 8 is adhered to a surface of a vibration-proof rubber 6 adhered to a nose portion 4, and a frame member 1 is tightened and coupled to the plate member 8 with a screw 17. As a result, the anti-vibration rubber 6 is not tightened by the screw 17,
Unaffected by variations in the tightening of the screws 17, variations in the compression force of the antivibration rubber 6 are reduced, and the parallelism between the frame member 1 and the nose portion 4 is improved. Further, since the rigid body connecting portion by the screw 17 is eliminated, the propagation of vibration is suppressed.

Description

[Detailed description of the device]

[0001]

[Industrial application]

 The present invention relates to a print head mounted on a dot impact printer used for an output device of a computer, and more particularly to a technology for preventing noise generated during its operation.

[0002]

[Prior Art]

 Conventionally, a print head for a dot impact printer using a piezoelectric element has a nose for guiding a front end of each print wire of the print unit in a print direction by a frame member in which a plurality of print units for printing a print medium are arranged. It is attached to the section with screws. The frame member and the nose portion are made of metal or other rigid body. For this reason, when the printing operation is performed, the frame material vibrates along with this operation, and this vibration may be transmitted to the nose portion, and noise may be generated from the nose portion.

As one of the means for solving this problem, for example, as disclosed in Japanese Patent Laid-Open No. 3-71855, in order to prevent or reduce noise generated from the nose part, a contact surface between the frame part material and the nose part A print head is known in which a vibration damping member is interposed between them. The vibration damping member is made of a vibration damping material such as rubber or synthetic resin, and functions to absorb and suppress the vibration of the frame member. A configuration equivalent to the vibration isolation structure shown in the publication will be described with reference to FIG. In FIG. 3, a frame member 1 is a support frame 2 to which a plurality of printing units 3 are fixed, and a nose portion 4 is for inserting a printing wire 5 of the printing unit 3 to support the frame member 1. The frame 2 and the nose portion 4 are fixed by screws 7 with a vibration-proof rubber 6 sandwiched between them.

[0004]

[Problems to be solved by the device]

 However, in this configuration, due to variations in the tightening of the plurality of screws, the compression force of the anti-vibration rubber, the parallelism between the frame member and the nose portion, and the like are likely to vary, which causes deterioration of print quality. Further, in the above fixed structure, since the support frame 2 and the nose portion 4 are rigidly coupled to each other via the screw 7, the vibration of the printing unit 3 is transmitted to the nose portion 4, and the vibration damping effect is obtained. Was reduced by that amount.

The present invention solves the above-mentioned problems, and can suppress the compression force of the anti-vibration rubber and the variation in the parallelism between the frame member and the nose portion, and reduce the propagation of vibration. An object of the present invention is to provide a print head for a dot impact printer, which is capable of preventing deterioration of print quality.

[0006]

[Means for Solving the Problems]

 In order to achieve the above object, the invention of claim 1 comprises a frame member in which a plurality of printing units for printing on a printing medium are arranged, and a nose portion for guiding the front end of each printing wire of the printing unit in the printing direction. In a print head for a dot impact printer having, the frame member and the nose portion are connected via a vibration-proof rubber, and one of the nose portion and the frame member is provided on one surface of the vibration-proof rubber. The plate member is bonded to the other surface of the anti-vibration rubber, and the other of the nose portion and the frame member is fixed to the plate member by a fastening means such as a screw.

The invention of claim 2 has a frame member in which a plurality of printing units for printing on a printing medium are arranged, and a nose portion for guiding the front end of each printing wire of the printing unit in the printing direction. In the print head for the dot impact printer described above, the frame member and the nose portion are joined together via a vibration-proof rubber, and plate members are adhered to both surfaces of the vibration-proof rubber. The frame member is fixed to the plate member, and the nose portion is fixed to the other plate member by fastening means such as screws.

[0008]

[Action]

 According to the above configuration, the frame member and the nose portion are coupled via the vibration isolating rubber, and the vibration isolating rubber is not tightened by the screws, so that it is not affected by the variation in tightening the multiple screws. , The variation in the compression force of the anti-vibration rubber is reduced, and the parallelism between the frame member and the nose portion is improved. Further, since the rigid body connecting portion due to the fastening means such as screws is eliminated, the propagation of vibration is suppressed.

[0009]

【Example】

 Hereinafter, a print head according to a first embodiment of the present invention will be described with reference to FIG. The print head mainly comprises a frame member 1 and a nose portion 4, and the frame member 1 has a disk-shaped support frame 2 on which a plurality of print units 3 are radially arranged. The printing unit 3 has a piezoelectric element 9 in which piezoelectric ceramics are laminated in a laminated shape, and a printing wire that moves forward and backward in conjunction with expansion and contraction of the piezoelectric element 9 and prints on a printing sheet via an ink ribbon (not shown). It consists of 5, etc. Further, the support frame 2 is provided with four through holes 10 through which a screw for connecting with the nose portion 4 is inserted at intervals of 90 °.

The nose portion 4 is for inserting the printing wire 5 of the printing unit 3, and on the surface side of the nose portion 4 facing the frame member 1, a disk-shaped anti-vibration rubber 6 is provided for noise prevention. It is provided by vulcanization adhesion or the like. Further, a disk-shaped plate member 8 is attached by vulcanization adhesion or the like to the surface side of the anti-vibration rubber 6 facing the frame member 1. A material such as stainless steel is used for the plate member 8, and a screw hole 11 is cut so as to face the through hole 10 of the support frame 2. Then, the support frame 2 and the plate member 8 are superposed on each other, and the through hole 10 is inserted from the rear surface of the support frame 2 (on the right side in FIG. 1) and the screw 17 is fastened to the screw hole 11, so that both are fixed. As a result, the frame member 1 and the nose portion 4 are joined together with only the antivibration rubber 6 interposed. Then, a bottomed cylindrical cover (not shown) is attached to the nose portion with the support frame 2 and the printing unit 3 in a non-contact state.

In the above print head, when a voltage is applied to the piezoelectric element 9, the piezoelectric element 9 expands in the stacking direction, and this expansion motion is expanded and transmitted to drive the print wire 5 to project. As a result, dots are printed on the opposing printing paper (not shown) via the ink ribbon. Since the anti-vibration rubber 6 is not tightened by the screws 17, this print head is not affected by the unevenness of tightening of the four screws 17, so that the unevenness of the compression force of the anti-vibration rubber 6 is reduced and The parallelism between the member 1 and the nose portion 4 is improved. Further, since the support frame 2 and the nose portion 4 are not rigidly connected to each other via the screw, the vibration of the printing unit 3 during operation is not transmitted to the nose portion 4. As a modification of this embodiment, the anti-vibration rubber 6 may be adhered to the support frame 2, and the nose portion 4 may be screwed to the plate member 8 adhered to the anti-vibration rubber 6.

Next, a print head according to the second embodiment will be described with reference to FIG. In the figure, the same reference numerals as those used above indicate the same members. The difference from the above is that the plate members 8a and 8b are attached to both sides of the antivibration rubber 6 by vulcanization adhesion or the like, and the respective plates are attached. The point is that the frame member 1 and the nose portion 4 are fastened and fixed to the members 8a and 8b with screws 17a and 17b. That is, the nose portion 4 is also provided with a through hole 12 equivalent to the through hole 10 of the support frame 2, and the plate members 8a and 8b have screw holes 11a and 11b facing the through holes 10 and 12, respectively. The frame member 1 and the nose portion 4 are fixed to the plate members 8a and 8b by inserting the screws 17a and 17b into the through holes 10 and 12 and tightening the screw holes 11a and 11b. Both of them will be joined with the anti-vibration rubber 6 interposed. Also in this embodiment, the same operational effect as the previous embodiment can be obtained.

It should be noted that although the screw holes 11a and 11b are in the same phase for easy understanding in the figure, it is advantageous to provide them at positions deviated from each other in terms of suppressing vibration. Further, as the material of the anti-vibration rubber 6, a material having a rubber hardness of about 60 degrees and a thickness of about 2 mm is used.

[0014]

[Effect of the device]

 As described above, according to the present invention, in the print head for the dot impact printer, the frame member and the nose portion of the printing unit are coupled via the vibration isolating rubber, and the vibration isolating rubber is tightened by the screw. It will not be affected by variations in tightening of fastening means such as screws. Therefore, the fluctuation of the compression force of the vibration proof rubber is reduced, and the parallelism between the frame member and the nose portion is improved. Moreover, the support frame and the nose portion are not rigidly connected by a fastening means such as a screw. As a result, the vibration of the printing unit is not transmitted to the nose portion, the propagation of the vibration can be suppressed, the noise can be reduced, and the deterioration of the printing quality can be prevented.

[Brief description of drawings]

FIG. 1 is an exploded view of a print head for a dot impact printer according to a first embodiment of the present invention.

FIG. 2 is an exploded view of a print head for a dot impact printer according to a second embodiment of the present invention.

FIG. 3 is an exploded view of a print head for a dot impact printer according to the related art.

[Explanation of symbols]

 1 Frame member 2 Support frame 3 Printing unit 4 Nose part 5 Printing wire 6 Anti-vibration rubber 7,17,17a, 17b Screw 8,8a, 8b Plate member

Claims (2)

[Scope of utility model registration request] 1. A print head for a dot impact printer having a frame member in which a plurality of print units for printing on a print medium are arranged, and a nose portion for guiding the front end of each print wire of the print unit in the print direction. The frame member and the nose portion are coupled via a vibration-proof rubber, one of the nose portion and the frame member is bonded to one surface of the vibration-proof rubber, and the plate is attached to the other surface of the vibration-proof rubber. A print head for a dot impact printer, wherein members are bonded and the other of the nose portion and the frame member is fixed to the plate member by fastening means such as screws. 2. A print head for a dot impact printer, comprising: a frame member in which a plurality of print units for printing a print medium are arranged; and a nose portion for guiding a front end of each print wire of the print unit in a print direction. The frame member and the nose portion are joined together via a vibration-proof rubber, and plate members are adhered to both surfaces of the vibration-proof rubber,
A print head for a dot impact printer, wherein the frame member is fixed to the one plate member, and the nose portion is fixed to the other plate member by fastening means such as screws.