JPH0354916Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field This invention relates to a print head for a dot printer, and more particularly to a holding structure for a plurality of armatures.

Purpose of the invention The purpose of this invention is to regulate the operation of a plurality of armatures arranged on a support member to a predetermined position in the retraction direction of the printing wire, and to press the outer end of each armature against the support member to a predetermined position. It is an object of the present invention to provide a print head that can reliably achieve the function of holding the print head in a supporting position with a simple structure.

Structure of the invention In order to achieve the above-mentioned object, the invention provides a printing head in which armature holding members are arranged in correspondence with a plurality of printing wire actuating armatures arranged radially on a support member. forming radial grooves while leaving partition walls on the support member;
A regulating part for regulating the operation of the armature in the direction of retraction of the printing wire is provided in the center of the holding member, and a regulating part is provided on the outer periphery of the regulating part to be latched to the supporting member when the regulating part comes into contact with the supporting member. The armature is provided with a plurality of protruding locking claws and a plurality of elastic holding portions for pressing the outer end of the armature against the support member.

Embodiment Hereinafter, an embodiment of this invention will be described in detail with reference to the drawings.

Now, the print head of the dot printer of this embodiment consists of an electromagnetic device assembly 1 and a print wire assembly 2.
and an assembly 3 for assembling both 1 and 2.

The electromagnetic device assembly 1 includes a substantially cylindrical yoke 4.
A plurality of (24 in this embodiment) electromagnetic devices 5
A plurality of slits 4b corresponding to each electromagnetic device 5 are formed at one end of the outer periphery of the yoke 4, leaving a partition wall 4a. Each electromagnetic device 5 includes a core 6 formed integrally with the yoke 4 and a coil 8 wound around the core 6 via a bobbin 7.
Both terminals of the coil 8 are respectively connected to a pair of connection pins 9 protruding from the bobbin 7. A printed circuit board 11 is fixed to the other side of the yoke 4 with an insulating plate 10 in between, and the connecting pins 9 are passed through this printed circuit board 11 and soldered. In this state, the side surface of the printed circuit board 11 is covered with the protective rubber sheet 12.

The printing wire assembly 2 includes a nose member 13 made of synthetic resin that is inserted into the electromagnetic device assembly 1, and therein eight wire guides 14, 1.
5 and 16 are arranged and fixed at a predetermined interval, and a flange-shaped support member 17 is integrally formed on the outer periphery of the base end. A plurality of holding grooves 17a are formed radially on the side surface of the support member 17, and a projection piece 17b that fits into the slit 4b of the yoke 4 is provided on the outer periphery of the support member 17 corresponding to each holding groove 17a. A supporting recess 17c is formed on the side surface of each protruding piece 17b.

In each holding groove 17a of the support member 17, armatures 18 made of plate-like members are accommodated and arranged with their wide side surfaces adjacent to each other, and a convex portion 18a is formed at one outer end of the armatures 18. is engaged with the support recess 17c on the support member 17 and is rotatably supported on the support member 17.
A support member 17 is provided at the center of one side of each armature 18.
A protrusion 19 corresponding to the core 6 of the electromagnetic device 5 is formed through the upper through hole. Further, a printing wire 21 is fixed to one side of each armature 18 so as to protrude and extend parallel to its wide side surface, and these printing wires 21 are connected to each wire guide 16, 1.
5 and 14 and extends toward the platen 20 side.

A spring 22 is provided in each holding groove 17a of the support member 17 corresponding to each armature 18, and the action of this spring 22 biases each armature 18 in the retracting direction of the printing wire 21. Then, as the electromagnetic device 5 is energized, the armature 1
8 is attracted and rotated toward the core 6 against the action of the spring 22, and the printing wire 21 is projected toward the platen 20.

Further, a holding member 23 made of synthetic resin is provided on the side of the support member 17 in correspondence with the armature 18 . As is clear from the drawing, there is a ring-shaped regulating part 24 in the center of the holding member 23 that engages with the central part of the side surface of the supporting member 17 and the side edge of each armature 18, on the right side of the supporting member 17 in FIG. Eight locking claws 2 are provided on the outer periphery of the surface and engage with the engaging portions 25 on the support member 17.
6 is formed protrudingly. The restricting portion 24 of the holding member 23 restricts the movement of the armature 18 in the printing wire retraction direction based on the action of the spring 22, so that each armature 18 is positioned and held at a predetermined position. In addition, 24 elastic holding parts 2 are provided on the outer periphery of the regulating part 24.
7 is integrally formed to protrude, and the convex portion 18a at the outer end of each armature 18 is connected to the support recess 17 of the support member 17.
c, and press them toward the armature 18.
is held at a predetermined position on the support member 17.

The assembly body 3 is an assembly member 2 made of a plate spring material.
8 and a metal lid body 29 attached to the outer surface of the assembly member 28. Three elastic legs 30 are formed protruding from the outer periphery of the assembly member 28, and the protrusions 29a on the lid body 29 engage with the inner surface of their bases, thereby connecting the assembly member 28 and the lid body 29. are combined. Further, each leg portion 30 engages with a step-shaped engaging portion 31 provided on the outer periphery of the yoke 4 of the electromagnetic device assembly 1 at a locking portion 30a formed at the tip thereof and having a substantially horizontal T-shape. The printing wire assembly 2 is sandwiched and held between the electromagnetic device assembly 1 and the printing wire assembly 2. Further, a pressing portion 32 is provided at the center of the assembly member 28, and is adapted to press the holding member 23 in the direction in which the printing wire protrudes.

Now, in this embodiment, as mentioned above, 1
On each holding member 23, there is a ring-shaped regulating part 24 for regulating the operation of each armature 18 in the printing wire retraction direction, and a plurality of ring-shaped regulating parts 24 for pressing the outer end of each armature 18 toward the supporting member 17 side. A holding portion 27 and a locking pawl 26 having elasticity are integrally provided. Therefore, the structure of the holding member 23 is extremely simple, and by simply attaching this one holding member 23 to the side surface of the supporting member 17, pressure can be applied to the base ends of a large number of armatures 18 arranged on the supporting member 17. Not only can holding and operation regulation at the tip be performed simultaneously, but also the holding member 2
3 is locked and held by the support member 17.

In addition, in this embodiment, as shown in FIG.
A plurality of positioning protrusions 33 are formed protruding from the side surface of the support member 17 so as to engage with the outer circumferential surface of the support member 17 . Thereby, the holding member 23 is attached to the supporting member 17.
The armature 18 is fixedly positioned and held at a predetermined position on the side surface of the armature 18, and each holding portion 27 of the holding member 23 is reliably held in a state of engagement with the base end portion of the armature 18.

It should be noted that this invention is not limited to the configuration of the above-mentioned embodiments, and it is also possible to embody the invention by changing the configuration of each part arbitrarily within a range that does not depart from the spirit of this invention.

Effects of the invention As detailed above, in this invention, the holding member is constructed by integrally forming the regulating part, the locking pawl, and the holding part, so that after the armature is assembled in the support member, the locking pawl is engaged with the support member. By doing so, the holding member can be easily attached to the supporting member, and handling during subsequent assembly becomes easy. By attaching the holding member as described above, it is possible to restrict the retraction direction of the printing wire in the operating range of the plurality of armatures arranged on the support member to a predetermined position, and to press the outer end of each armature against the support member. The function of holding the support at a predetermined support position can be reliably performed with a simple structure. In particular, since the regulating part contacts the support member and determines the position of the armature in the direction of retraction with respect to the support member, the return position of the armature is reliably determined, and as a result, it is possible to almost eliminate variations in the strokes of the armature and the printing wire. It has excellent effects.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of a printing head embodying this invention, FIG. 2 is a sectional view taken along line A--A in FIG. 1, and FIG. 3 is a partially exploded perspective view. 1 is an electromagnetic device assembly, 2 is a printing wire assembly,
17 is a supporting member, 18 is an armature, 21 is a printing wire, 23 is a holding member, 24 is a regulating portion, 27
is the holding part.

Claims (1)

[Claims for Utility Model Registration] In a printing head in which an armature holding member 23 is disposed in correspondence with a plurality of armatures 18 for operating printing wires arranged radially on a support member 17, the support member 17 is provided with: A radial groove 17a is formed leaving the partition wall portion, and a regulating portion 24 is provided at the center of the holding member 23 for regulating the operation of the armature 18 in the printing wire retraction direction, and on the outer periphery of the regulating portion 24, The regulating portion 24 is the support member 17
A plurality of locking claws 26 are locked to the support member 17 when the armature 18 comes into contact with the support member 17, and a plurality of elastic holding portions 27 for pressing the outer end of the armature 18 toward the support member 17 are protruded. A print head characterized by the following: