JPH0482743A - Printing head for dot impact printer - Google Patents

Abstract

PURPOSE:To achieve a reduction in noise with a decrease in return impact by dividing plate springs each with a slight gap between the spring and a stopper rubber into the number same as that of armatures to be formed in a shape of a petal so that both of outer and inner circumference parts of the plate springs are supported to allow a quick rising. CONSTITUTION:A stopper plate 17 is provided with slits same in number as armatures on a disc-shaped plate and given a shape of a petal in no way affecting actions of any adjacent armature 2. A rubber plate 17b is put between two spring plates 17a and 17c and both of outer and inner circumference parts of the spring plates are supported with a stopper 13 so that an action is created to absorb an impact when an armature arm 2a abuts on the stopper plates. Moreover, a gap G is provided between the stopper plate 17 and a stopper rubber 13a and hence, at the start of a printing, a return spring 5 is damped by a spring force of the stopper plate 17 to allow a quick rising of action. This reduces a return impact speed to prevent deformation and wearing thereby achieving a reduction in noise.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a print head for use in a dot impact printer.

[Conventional technology]

Conventional print heads used in dot impact printers are mainly configured to use magnetic attraction force as a means for driving the print wire, and to drive the print wire by rotational movement of an armature. This type of print head has a stopper made of metal or synthetic resin to hold the armature in a stationary position when not printing (non-printing) and to stop the rotational movement of the armature after printing. It is set up.

[Problem to be solved by the invention]

As mentioned above, the print head of conventional dot impact printers uses metal or synthetic resin as the stopper to stop the rotating movement of the armature, so when the armature collides with the stopper, It does not stop immediately, but after repeating the balun l- several times. Therefore, when high-speed printing is performed, the printing operation becomes unstable and the printing quality deteriorates. Another disadvantage is that a large amount of noise is generated due to the collision between the armature and the stopper. To deal with this, some methods use rubber as the stopper material, but this has the disadvantage that the rubber deforms or wears out due to collision with the armature, making printing operations difficult. .

Furthermore, in order to perform high-speed printing, the thickness of the armature must be made thinner to reduce weight, but if the thickness of the armature is made thinner, deformation and wear occur at the part that collides with the stopper, so it is necessary to reduce the weight of the armature. It also has the disadvantage of being difficult.

[Means to solve the problem]

The print head of the desotoinvacto printer of the present invention is
a plurality of print wires; an armature that performs printing by rotating the print wires and hitting the print surface; and a rotation of the armature located on the opposite side of the print surface with respect to the armature. A stopper for stopping the movement, a stopper comb provided on the stopper, and a leaf spring provided with a slight gap between the stopper rubber and the number of the leaf springs equal to the number of the armatures. The leaf spring is divided into two parts, and either the outer peripheral part or the inner peripheral part is connected in a circular shape to form a petal shape, and both the outer peripheral part and the inner peripheral part are supported. It has a structure in which a rubber plate is sandwiched between two spring plates. [Example] Next, an example of the present invention will be described with reference to the drawings.

FIG. 1 is a half-sectional view showing one embodiment of the present invention, FIG. 2 is an exploded perspective view showing the armature and hold spring of the embodiment of FIG. 1, and FIG. 3 is an exploded perspective view of the armature of the embodiment of FIG. 1. 4 is a sectional view showing details of the vicinity of the tip, FIG. 4 is a perspective view showing the protection sheet of the embodiment shown in FIG. 1, and FIG. 5 is a perspective view showing the stopper plate of the embodiment shown in FIG.

In FIG. 1, the printed wire 1 is connected to the armature 2.
It is fixed to the tip with brazing. The armature 2 includes an armature block 2b as shown in FIG.
The armature arm 2a is fixed to the armature fulcrum 2c (the first
(see figure) is pressed against the inner yoke 10. The armature support 6 accommodates the return steering ring 5 (
(see Fig. 3), and a petal-shaped protection sheet 18 (
(see Figure 4).

Further, the armature support 6 holds the hold spring 3 through a square hole and prevents the armature arm 2a from swinging in the thickness direction (not shown).

In FIG. 1, the brake rubber 4 is sandwiched between the armature support 6 and the frame 2, and applies a constant load to the hold spring 3. The side magnetic path 7 is connected to the armature block 2b.
enters without contacting /117 w (see Figure 2), and has an inner yoke 10 and a thickness equal to that of the inner yoke]
It is stacked on the armature support 6 together with an outer yoke 8 and a yoke 9 that are equal to or larger than 0. The yoke 9 has a shape in which a cylindrical outer wall 9a, an inner wall 9c, and a plurality of prismatic cores 9b are provided on a disc-shaped bottom plate, and a coil 11 is wound around the core 9b. ing. The stopper rubber 13a and the stopper plate 17 are attached to the stopper 13 and are arranged so that the armature 2 can rotate by a predetermined angle. The stomper plate 17 is a disc-shaped plate with the same number of slits as the armature 2 (see Fig. 5), and as shown in Fig. 3, there is a gap between two spring plates 17a and 17c. It has a so-called sandwich structure with a rubber plate 17b sandwiched therebetween, and both its outer and inner circumferential parts are supported by the striker fly 3. For this reason, armature arm 2
It has the effect of absorbing the impact when a comes into contact with it.

With this configuration, when the coil 1 is selectively energized, the coil 11 generates a magnetic force, which attracts the armature block 2b to the core 9b. Therefore, the armature 2 rotates counterclockwise about the armature fulcrum 2C, and prints are made on the paper 15 on the platen 16 via the ink phone 14 using the print wire 1 fixed to the tip thereof. When the coil 11 is de-energized, the armature arm 2a is pushed by the return spring 5 through the protection sheet 18, so it rotates clockwise, collides with the strike plate 17, and comes to rest. The speed of this series of printing operations is a function of the moment of inertia of the armature 2, the force of the return spring 5, and the rest time when it collides with the stopper plate 17. Even if the thickness of the armature arm 2a is reduced in order to reduce the moment of inertia, the protection sheet 18 is present between the armature arm 2a and the return spring 5, so that wear of the armature arm 2a is prevented. Since the protection sheet 18 has a petal-like shape having the same number of tongue-shaped portions as the armature 2, it does not affect the operation of the adjacent armature 2. Further, since a stopper plate 17 is provided between the armature arm 2a and the stopper rubber 13a, the armature arm 2a is connected to the stopper rubber 13a.
Deformation and wear due to collision with 3a are prevented. Since the stopper plate 17 is provided with the same number of slits as the armatures 2, the operation of the adjacent armatures 2 is not affected. Furthermore, since a gap G is provided between the stopper plate 17 and the stopper rubber 13a (see FIG. 3), when the printing operation starts,
The force of the return spring 5 is weakened by the spring force of the stopper plate 17, and the start-up of the operation becomes faster. In addition, during the return operation, the armature arm 2a first collides with the stopper plate 17 to bend the stopper plate 17, and then collides with the stopper rubber 13a.
The collision speed is reduced to prevent deformation and wear, and also to reduce noise. As described above, the stopper plate 17 has a so-called sandwich structure in which the rubber plate 17b is sandwiched between the two spring plates 17a and 17c, so that it quickly damps vibrations after a collision of the armature arm 2a. , to make the operation of the armature 2 stable. Although it is necessary to manufacture the gap G with high precision, since both the outer circumference and the inner circumference of the stopper plate 17 are supported by the stopper 13, the stopper plate 17
The dimensional accuracy of the gap G can be easily ensured without increasing the accuracy of the flatness of the gap G.

〔Effect of the invention〕

As explained above, the print head of the dot impact printer of the present invention includes the stopper rubber provided on the stopper and the leaf spring provided with a slight gap between the stopper rubber and the leaf spring. By using a structure in which a rubber plate is sandwiched between two spring plates, and by supporting both the outer and inner circumferential parts of the plate springs with stoppers, the rise of the armature movement at the start of printing operation can be prevented. In addition to reducing the collision speed during the return operation, deformation and wear can be prevented, and noise can also be reduced. Therefore, it is possible to obtain a print head that is capable of high-speed printing, has good print quality, and has low noise. Furthermore, since the thickness of the armature can be made thinner, the speed can be further increased.

[Brief explanation of the drawing]

FIG. 1 is a half-sectional view showing one embodiment of the present invention, FIG. 2 is an exploded perspective view showing the armature and hold spring of the embodiment of FIG. 1, and FIG. 3 is an exploded perspective view of the armature of the embodiment of FIG. 1. Details near the tip III! FIG. 4 is a perspective view showing the protection sheet of the embodiment shown in FIG. 1, and FIG. 5 is a perspective view showing the stopper plate of the embodiment shown in FIG. 1...Alint wire, 2...Armature, 2a-...Armature arm, 2b...
... Armature block, 2c ... Armature fulcrum, 3 ... Hold spring,
4...-pressure rubber, 5...-return spring, 6...-armature support,
7... Side magnetic path, 7w... Groove, 8...
...Outer yoke, 9...Yoke, 9a...
...Outer wall, 9b...Core, 9c...
Inner wall, 10--5... Inner yoke, 11...
・Coil, ]2...Head frame, Co3...
...stopper, 13a...stopper rubber 1,
14... Ink ribbon, 15 Kawayama paper, 16.
...Platen, 17...Station/Soba plate, 17a, 17c...Spring plate, 17b...
...Rubber plate, ko8...Protection sheet.

Claims (1)

[Scope of Claims] 1. A plurality of print wires, an armature that performs printing by driving the print wires through rotational motion and hitting a print surface, and a side opposite to the print surface with respect to the armature. a stopper located on the stopper for stopping rotational movement of the armature; a stopper rubber provided on the stopper; and a leaf spring provided with a slight gap between the stopper rubber and the stopper rubber. The spring is divided into the same number of armatures, and either the outer or inner circumferential portion thereof is connected in a circular shape to form a flower petal shape, and both the outer circumferential portion and the inner circumferential portion of the leaf spring are supported. A dot impact printer print head featuring 2. A plurality of print wires, an armature that performs printing by driving the print wires through rotational movement and hitting the print surface, and an armature located on the opposite side of the print surface with respect to the armature; It has a stopper for stopping the rotational movement of the armature, a stopper rubber provided on the stopper, and a leaf spring provided with a slight gap between the stopper rubber and the leaf spring. It has a structure in which a rubber plate is sandwiched between spring plates, and the plate spring is divided into the same number as the number of armatures, and either the outer circumferential part or the inner circumferential part thereof is connected in a circular shape to form a petal shape, A print head for a dot impact printer characterized by supporting both the outer and inner circumferences of a spring.