JPS59156762A - Printer head unit - Google Patents

Abstract

PURPOSE:To silence noise caused by needle driving displacements by installing pressure driving member and return driving member formed with a shape memory material which elongates and contracts thermally by specific resistance of material and allowing reciprocating motions of needle by electric transmission control. CONSTITUTION:Under a non-transmission condition, a piston 3 is pushed into a center position inside a cylinder 4 by means of a return spring 15 through an insulating sleeve 6 natural lengths of driving members 13, 14 are equal as represented A=B. When a switching element 17 is placed in ''ON'' position, a closed circuit comprising source 16-switching element 17-electrode plate 9-pressure driving member 13-piston 3-cylinder 4 is completed and heat generation by natural resistance of the pressure driving member 13 causes a relation A>B and a stroke of the piston 3 to the RH side causes the needle 1 to assume a typing action by displacement by delta under pressure. When the switching element 17 is placed in ''OFF'' position and the element 18 in ''ON'' position, the needle 1 is allowed to make a return displacement by transmission heat of the return driving member 14. Thereby, impact load can be reduced and noise silenced.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to a printer head device for use in dot printers and the like.

Technical background of the invention and its problems Conventionally, dot printers print by displacing the needle under pressure, but since an electromagnet is used to operate the needle, a pulse voltage is applied to the coil and the armature is moved. When it is adsorbed to the yoke core, the suction noise is loud and is not suitable for quiet environments.

OBJECTS OF THE INVENTION The present invention has been made in view of the above points, and an object of the present invention is to provide a printer head device that can minimize noise when driving and displacing a needle.

Summary of the Invention The present invention includes a pressurizing drive member and a return drive member made of a shape memory material that generates heat and expands and contracts due to the material's specific resistance, and utilizes the shape memory property of the material by controlling the supply of electricity to these members. By reciprocating the needle, the noise generated when driving and displacing the needle can be minimized.

Embodiment of the Invention A π-th embodiment of the present invention will be described with reference to FIGS. 1 to 5. FIG. First, Fig. 1 shows the basic configuration of the driver (2) for the needle (1) of 1.
) is connected to the piston (3). This piston (
3) slides in the left and right direction inside the cylinder (4). Here, the cylinder (4) is a stainless steel pipe, and its inner surface is mirror-finished. Also, the piston (3
) is also made of a conductive material, and the outer periphery that joins to the inner surface of the cylinder (4) is polished.

Then, cylinders (4) are installed on the left and right sides of the piston (3).
A heat-resistant insulating sleeve (51 (6)
is provided. Furthermore, insulating materials (7) + 8) are attached to both ends of the cylinder (4) as lids. Each electrode plate (9) (1
0) is provided. Here, a hole Uυ housing 4 is formed in the insulating material (8) and the electrode plate (10), into which the needle (1) can freely slide.

In the cylinder (4), there is a knife mouth pressure drive member (13) located between the piston (3) and the insulator (7), and a return drive member (13) located between the piston (3) and the insulator (8). Each member a4a is provided. Here, both moving members u3
) (14) is formed into a coil spring shape using a shape memory material that expands and contracts due to heat generation due to the specific resistance of the material. In other words, it is a wire with a wire diameter of 0.2 to 0.37 nm and made of Ti or Ni.
For example, the winding pitch is 1.0 mm.
As for the degree, the coil is wound into a spring shape and heat treated at about 45'O℃ to memorize the shape, and after the heat treatment, both ends are pressed so that the winding pitch is about 0.5 degrees. )
It has been incorporated into the system. Here, both 1 drive members u31
One end of the inner side of (14) is fixed to the piston (3) for electrical connection, and the other end is fixedly connected to each electrode plate (9) α0).

A return spring (15) is provided between the insulating sleeve (6) and the insulating material (8) to press the piston (3) at a predetermined spring constant through the insulating sleeve (6).

Here, electrically, as shown in Figure 2, the cylinder (4)
is used as a common electrode, the - side of the DC power supply σ6) is connected, the + side is connected to the electrode plates (9) and (10), and the switching element (
17) The driving member (131
The energization of the circle is controlled.

In such a configuration, multiple operations will be explained with reference to FIGS. 2(α) to (G). First, the same figure (cL) shows a non-energized state, the piston (3) is insulated, and the cylinder (4) is returned to the initial position by the return spring (151) via the sleeve (6).
It is pressed in the center of the inside. At this time, the natural lengths of the left and right driving members a and α are equal to A=B. In this way,
The initial position of the piston (3), t and thus of the needle (1) is maintained stably.

However, as shown in the same figure, the switching element (17) is
When N, power supply (16) - switching element (17) - electrode plate (
9) A closed circuit of the pressure drive member (2), the piston (3), and the cylinder (4) (common electrode) is formed, and a pulse voltage is applied to the pressure drive member α3). By applying this pulse voltage, the pressurized drive member (1 fathom) exhibits shape memory properties,
If heat is generated due to the specific resistance of the material and the natural length immediately after heat treatment, that is, the winding pitch returns to the state of about 1.0 mm, one dimension becomes A>B. As a result, the piston (3) is pushed to the right, and the needle (1) is displaced by pressure by δ with respect to the initial position shown in FIG. After such printing, when the opening/closing element (17) is turned OFF and the opening/closing element (18) is turned ON, the return drive member (1) exhibits shape memory characteristics, as shown in (-) in the figure. The piston (3) is pushed back to the left together with the return spring (151), and the needle (1) is returned to the initial position similar to that shown in the same figure (cL).

The strength of the spring is as follows: A1 is the spring constant when energizing generates heat, 42 is the spring constant when energizing is interrupted, and A is the spring constant of the return spring (15).
, when you say that. >'3>'2.

By repeating such operations, the needle (1) moves back and forth to perform a printing operation. FIG. 3 is a timing chart of energization control for the pressurizing drive member α3) and the return drive member (one force).Since ON and OFF are performed at the same time, the response speed is fast.

Here, the head of the dot printer is constructed as shown in FIGS. 4 and 5, for example.

That is, a plurality of drive bodies (2) are arranged on the circumference, and each needle (1) is sequentially guided by the needle guide μ9) C!
0)', and the tips of the needles (1) are arranged in a predetermined vertical length by the tip guide circle. Then, by controlling the energization of each drive body (2) as necessary, the necessary needles (1) can be moved to the ink ribbon (
22) to be printed on plain paper (c). In addition, (Foundation) is a cooling fin.

Therefore, according to this embodiment, the pressure driving member (13)
A return drive member (1 piece) is provided, and its shape memory characteristics are used to pressurize and return the needle (1), making it possible to reduce noise when driving and displacing the needle (compared to the conventional armature method). .

Furthermore, since the impact load is small, the life of the ink ribbon can be extended.

Next, a second embodiment of the present invention will be described in FIGS. 6 to 10.
This will be explained with the help of a diagram. In the above embodiment, a coil spring-shaped pressure drive member (13) and a return drive member (14) were used, but in this embodiment, a plate-shaped pressure drive member (251) and a return drive member CO are used. , both moving members (25
) (26) are arranged opposite to each other with their lower ends fixed in position. Here, the pressure driving member (c) is the return driving member (2).
6), and a needle (1) is fixed to the upper end thereof in the shape memory direction. Here, the needle (1) is fixed to the pressure drive member (25) by brazing or the like, but as shown in FIG. It is made so that it does not protrude from the top edge. On the other hand, the return drive member (
261 is a pressurizing drive member (2) to avoid the needle (1).
51 is also made shorter, and its shape is memorized toward the pressure driving member (25) side.

Electrically, each driving member (251 (26)
) on the side from its apex side to terminal H C)9
1 AZ wiring, and the lead wire side is connected to the terminal (28). Also, a heat-resistant insulated wire c31) is wired from the lower side of both moving members (25) Q to a common terminal (321), and a common lead wire (to) is connected to this common terminal (3).

In such a configuration, the lead wire (to) connects the terminal (
If a pulse voltage is applied to the printing nozzle (251) shown in Fig. 8 to (c), the pressure drive member (251) will generate heat in response to only the +V signal, exhibiting shape memory characteristics, and following the shape memory direction. The needle (1) is fully advanced and displaced under pressure. Therefore, the distance between the two moving members (c) becomes narrower than the initial state. Then, at the same time as the +v wound signal turns OFF, the return driving member (4) ) is applied with the -■ signal and generates heat, exhibits shape memory characteristics, and operates toward the pressure drive member Q side.For this reason, the head of the return drive member (2E9) is connected to the pressure drive member (251). This pressurizing drive member ■
51 is forcibly returned to its initial state.

For this reason, the head of the return drive member (26) is provided with a surface protection film (three layers) for insulation and wear prevention.This causes the needle (1) to return to its original position.

Here, as the head of the dot printer, for example, the 9th
It is constructed as shown in FIGS. (351 is an insulating head body, each drive member (25) (26
) is supported (embedded) at the bottom. Since the tips of the needles (1) are arranged vertically in a straight line, the drive members e51 (4) are sequentially higher toward the rear.

Further, (36) and (37) are four-id needles, with the same needle hole spacing to prevent the tip of the needle (1) from wobbling as it reciprocates in the left-right direction in the figure. (38) is connected to the connector head body (lead wires 60 drawn out from the three recesses 6). Note that the arrow in FIG. 10 indicates the shape memory direction of the drive member (251 (26)).

Note that the present invention is not limited to application to dot printers. For example, the present invention can be applied to a printer in which ink held by an ink holding means is discharged as ink droplets into a magnetic field by pressurizing and displacing a needle, and the ink droplets are deposited on plain paper.

In short, any device that forms dots using mechanical energy based on the movement of the needle (1) can be applied.

Effects of the Invention As described above, the present invention includes a pressurizing drive member and a return drive member formed of a shape memory material that generates heat and expands and contracts due to the material's specific resistance, and controls the current supply to these members to control the return drive member. Since the needle is reciprocated using its shape memory property, the noise generated when the needle is driven and displaced can be minimized.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional side view showing the first embodiment of the present invention, and the second
Figures (cL) to (G) are longitudinal side views showing the operation, Figure 3 is a timing chart, Figure 4 is a side view of the entire head, Figure 5 is its layout, and the vJG diagram is the second diagram of the present invention. A perspective view showing the embodiment; FIG. 7 is a rear view showing an enlarged part of the embodiment;
FIG. 8 is a timing chart, FIG. 9 is a front view of the entire RAD, and FIG. 10 is a vertical side view thereof. 1 Needle, 3...Piston, 4...Cylinder, 7
~8 Insulating material, 9~10・Electrode plate, 13・Pressure drive member, 14・Return drive member, 15・Return spring, 25・Pressure 1 drive member, 26・Return drive member amount Applicant Tokyo Electrical Co., Ltd. AJ Diagram U-Diagram Procedures Amendment (Spontaneous) April 12, 1981 1 Indication of Case Patent Application No. 1983-31396 2 Title of Invention Printer Head Device 3, Person Who Makes Amendment Case Relationship with Patent applicant 4 Agent, 107 Name 7211 Patent attorney Akira Aiki 5 Date of amendment order Regarding this application, the description and drawings are amended as follows. Note 1, "Piston (3)" on page 6, line 8 in the clear text.
, therefore, the needle (1) is corrected to the piston (3) and the needle (1). 2.Amend Figure 4 in the drawings as shown in the attached sheet. The wings are also U-kombu

Claims (1)

[Scope of Claims] 1. A pressurizing drive member that pressurizes and displaces the needle and a return drive member that returns and displaces the needle are formed of a shape memory material that expands and contracts with heat due to the inherent resistance of the material. A printer head device characterized in that a needle is reciprocated by controlling energization to a pressure drive member and a return drive member. 2. A pressurizing drive member that pressurizes and displaces the needle and returns the needle to displacement. The return drive member is formed in the shape of a coiled spring from a shape memory material that heats up and expands and contracts due to the inherent resistance of the material, and is disposed between the pressurization drive member and the return drive member and is attached to one end of these members. A conductive piston is provided that is electrically connected and has the needle attached thereto, and a conductive cylinder that guides the sliding movement of the piston is provided, and the pressure drive member and the return drive are attached to both ends of the cylinder. A printer head device characterized in that an insulating material having an electrode plate in contact with the other end of the member is provided, and a shader is reciprocated by controlling the supply of electricity to the pressure driving member and the return driving member. 3. The printer head device according to claim 2, wherein the cylinder is used as a common electrode for the pressurizing drive member and the return drive member via a piston. 4 A pressure drive member that presses and displaces the needle and a return drive member that returns and displaces the needle are formed in the shape of a coil spring from a shape memory material that expands and contracts heat due to the material's specific resistance, and these pressure drive members and a return drive member, the piston having the needle attached thereto, a cylinder for guiding the sliding movement of the piston, and a return spring for maintaining the piston at an initial position within the cylinder in a non-energized state. A printer head device characterized in that the p-needle is reciprocated by controlling the supply of electricity to the pressure drive member and the return drive member.