JPH0716436Y2 - Wire dot head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to the structure of a wire dot head.

[Conventional technology]

It will be described with reference to FIG. The conductive wire 42 is coiled along the coil frame 41. A coil terminal 43 is inserted into the coil frame up to the bottom of the terminal insertion hole of the coil frame, and the end of the conducting wire is entangled with the coil terminal portion. The coil 42 is incorporated in the yoke coil core 45-a portion. The coil terminals are soldered to the board at the board lands provided on each pattern section on the board 44. As a result, an electric current flows through the substrate pattern in response to the print signal, and a magnetic flux is generated in the coil portion for printing.

The above-described step of twisting the conductor to the coil terminal portion is usually performed by hand twisting after coiling or by a coiling machine equipped with an automatic twisting mechanism.

[Problems to be solved by the device]

However, in the above-mentioned structure, in order to surely carry out the end treatment of the conductor after the conductor is entwined with the coil terminal, the conductor must be cut manually by using a cutter or scissors. Also, when conducting a conductor with a coiling machine equipped with an automatic tangling mechanism, it is common to cut the conductor by applying a certain amount of tension to the conductor. It is very likely that the coil will be cut off with the state left on the coil terminal side. If the whisker-shaped conductor is incorporated with the conductor left, it will electrically leak to the yoke 45 in FIG. 4, resulting in so-called insulation failure and a fatal defect in the wire dot head. For this reason, the beard-like conductor wire at the barbed portion of the coil terminal must be manually corrected or discarded after a 100% screening process after the conductor wire is stripped.

Therefore, the present invention solves the problems such as 100% selection process and manual correction.
An object of the present invention is to provide a wire dot head in which a coil terminal portion for conducting a conductor wire is surely cut off at the end of the conductor wire.

[Means for Solving the Problems]

The wire dot head according to the present invention is a wire dot head that energizes a conducting wire wound around a coil frame to drive a printing wire, and a coil terminal is erected on the end surface of the coil frame, and the coil terminal is angular. An edge portion provided with an edge and a base portion having a smooth surface formed between the edge portion and the end surface of the coil frame are provided, and the end of the conductive wire wound around the coil frame is wound around the base portion. After that, it is characterized by being cut at the edge portion.

[Action]

With the coil terminal shape as described above, when the wire is completely removed from the conductor, if a certain tension or more is applied, the bush part of the coil terminal acts as if it is a blade, without leaving a mustache-shaped conductor. Conducting wire plucking and cutting can be performed.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows an embodiment of the present invention using a machine equipped with an automatic twisting mechanism. 1 is a coil frame, 1-a is a hole for inserting a coil terminal, 2 is a coiled conductor wire, 2-a is a terminating end of the conductor wire, 2-b is a conductor winding start side, 3 is a coil terminal, 3- a is a coil terminal bushing part. The coil frame is made of a plastic material that has heat resistance in consideration of the heat generation temperature when the head is used and has mechanical strength capable of covering the press-fit stress of the coil terminal. The coil terminal is pierced by the coil terminal piercing machine into the coil terminal piercing hole of the coil frame to a certain depth l. The terminal piercing machine has a die capable of piercing a coil terminal for a certain length and simultaneously performing shaving and cutting. Coiling is performed with one coil terminal side as the winding start side,
After the coiling to the coil frame is completed, the other coil terminal different from the winding start side is twisted and the lead wire is cut. On the winding start side, it is usually effective to perform wrapping around the coil terminal and lap winding to prevent loosening. It is necessary to wind the winding start side so that it does not reach the coil terminal bush to prevent the conductor wire from breaking. On the other hand, at the end portion of the conducting wire which has been coiled, at the end of the curling, the conducting wire is twisted so as to engage with the coil terminal bushing portion, and a constant tension is applied to the conducting wire. As a result, the conductor wire is cut off neatly at the angled edge portion 3-a of the coil terminal bush without leaving a beard-shaped conductor wire.

Here, the most characteristic feature of the present invention is the partial addition of the bush shape to the coil terminal in order to improve the cutability of the final portion of the conductor wire, but if the purpose is simply cutability, If the wire for the coil terminal has a rectangular cross section or a wire for the coil terminal having an edge portion, the cuttability is ensured. However, because of the usual usability as a product such as a wire dot head, it is constantly exposed to mechanical vibration due to printing operation.
From the viewpoint of ensuring long-term reliability, we do not want to use coil terminals made of wire with a square cross-section. Therefore, the conductor barb is excellent in the cross-sectional shape of the coil terminal without corners, which is sufficient to satisfy the function required for the bark itself. It will be good if given.

FIG. 2 shows a coil terminal wire 23 having a circular cross section, which is provided with a bush. An embodiment in which a wire rod 33 having a square cross section is used is shown in FIG. This is an application example in which a corner is dropped and rounded at a place where a tangle is required.

[Effect of device]

The wire dot head according to the present invention has a coil terminal having an edge portion provided with angular edges and a base portion having a smooth surface formed between the edge portion and the end surface of the coil frame. The end of the wire wound around is cut at the edge after it is wound around the base, and the surface of the base around which the wire is wound is smooth, so the wound wire does not get scratched. It is possible to prevent breakage of the conductive wire, suppress occurrence of defects such as short circuit and leak, and improve product quality. Moreover, since the edge portion acts as if it is a blade and the conductor wire is cut by simply applying a certain tension or more to the conductor wire after the winding work, automation of the work is facilitated.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention. 2 (a) and 2 (b) are a side view and a front view showing an embodiment of the coil terminal according to the present invention. 3A and 3B are a side view and a front view showing another embodiment. FIG. 4 is a sectional view showing a conventional example. 1 ... Coil frame 1-a ... Coil terminal puncturing hole 2 ... Conductor wire 2-a ... Conductor end of wire twisting 2-b ... Conductor winding start side 3 ... Coil terminal 3-a .. Edge part

Claims (1)

[Scope of utility model registration request] 1. A wire dot head for energizing a conducting wire wound around a coil frame to drive a printing wire, wherein a coil terminal is erected on an end face of the coil frame, and the coil terminal has a square edge. An edge portion provided and a base portion having a smooth surface formed between the edge portion and the end surface of the coil frame are provided, and an end of the conductive wire wound around the coil frame is wound around the base portion. After that, the wire dot head is cut at the edge portion.