JPS6317213B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is primarily concerned with the durability of electromagnets. Electromagnets convert electric power into mechanical motion, so-called electricity.
Although it is widely used as a mechanical conversion element, there are often problems with the durability of the collision surface of the movable element and the collided surface that is collided with the movable element when a collision occurs due to the suction operation of the movable element. . Conventionally, in order to deal with this problem, durability has been improved by applying surface hardening treatments such as carburizing and quenching, plating, etc. to the impact surface and the impact surface. However, the colliding surface and the collided surface are often part of the magnetic path, and applying a relatively thick hardened layer, such as carburizing and quenching, lowers the magnetic permeability and reduces the electromagnet's attraction characteristics. It had become a drawback. Furthermore, the plating process has a disadvantage in that the plating tends to peel off due to the impact caused by collisions. In view of the above, an object of the present invention is to obtain an electromagnet with excellent durability and reliability that reduces the attraction characteristics of the electromagnet. The gist of the present invention for achieving the above object is that in an electromagnet including a movable element and a limiting member that limits the suction operation range of the movable element, the movable element and the limiting member collide. A film of a titanium compound is formed by ion plating on at least one of the collision surface of the movable element and the collision surface of the limiting member. A specific example in which the present invention is applied to a print head electromagnet of a dot matrix printer and a hammer driving electromagnet of a line printer will be described below. 1 and 2 are cross-sectional views showing a print head of a dot matrix printer and a hammer drive mechanism of a line printer, respectively. In FIG. 1, a frame 1 serves as the base frame of the print head, and is fixed to a print head carrier (not shown) for moving the print head in the print line direction (perpendicular to the paper surface). The substantially U-shaped iron core 2 is made of a magnetic material with high magnetic permeability, and is attached to the frame 1.
Fixed. A coil 3 is wound around the left leg 2a of the iron core 2. The mover 4 is made of a magnetic material having high magnetic permeability, and a film of a titanium compound, such as titanium carbide, is formed by ion plating on a collision surface 4a that collides with a magnetic spacer 8, which will be described later. Further, the movable element 4 is pivotably attached to a movable element shaft 5 fixed to the right leg portion 2b of the iron core 2. In this structure, the iron core 2 serves as a limiting member that limits the suction operation of the movable element 4. The movable spring 6 has a hook portion 2 protruding from the right leg portion 2b of the iron core 2.
A tension spring suspended between C and the end 4b of the movable element 4 biases the movable element 4 clockwise to press it against the movable element stopper 7 fixed to the frame body 1, and the movable element 4 in a standby position. The magnetic spacer 8 is made of a non-magnetic material and is fixed to the upper end of the left leg portion 2a of the iron core 2, and is arranged so that the movable element 4 quickly returns to the standby position after performing the suction operation. Other than the frame 1 and the movable element stopper 7 mentioned above, seven driving units are arranged in a circumferential manner with the printing needle contacting part 4c of the movable element 4 inside as drive units for driving the printing needle 9, which will be described later. has been done. The printing needle 9 is attached to each movable element 4 arranged in a circumferential manner.
The printing stylus contacts the printing stylus abutting portion 4c, and the three printing stylus guides 10, 11, and 12, which will be described later, form a straight line (in the left-right direction on the paper surface) at a position immediately before contacting the recording paper 16. It is composed of The first printing needle guide 10, the second printing needle guide 11, and the third printing needle guide 12 are connected to a printing needle guide base 13 fixed to the frame 1.
The printing needle 9 is configured to be guided smoothly from the movable element 4 side, which is arranged in a circumferential manner, to the recording paper 16 side, which is linearly arranged. The printing needle return spring 14 is a compression spring held between the printing needle 9 and the first printing needle guide 10. The printing needle return spring 14 is a compression spring that is held between the printing needle 9 and the first printing needle guide 10. 9 in a standby position. The cylindrical platen 15 is a printing force receiving member that receives the printing force of the printing needle 9, and both ends thereof are rotatably supported by a printer frame (not shown). A recording paper 16 is in contact with the outer periphery of the platen 15 over an appropriate arc length, and a recording paper feeding means (not shown) is provided.
It is configured to be transported intermittently by. The ink ribbon 17 is provided close to the surface of the recording paper 16 and is provided with an ink ribbon feeding means (not shown).
It is configured to run in the printing line direction by the following. The operation of the print head in the above configuration will be explained. Corresponding coil 3 according to the printing command
When the magnetization is performed, an electromagnetic force acts on the movable element 4 corresponding to the excited coil 3, and the movable element 4 swings counterclockwise against the biasing force of the movable element spring 6, and the magnetic spacer 8 The left leg 2a of the iron core 2 through
collide with Due to this swinging, the corresponding printing needle 9 is driven against the biasing force of the printing needle return spring 14,
Dots are recorded by striking the recording paper 16 through the ink ribbon 17. When the excitation to the coil 3 is cut off, the printing needle 9 returns to its standby position by the urging force of the printing needle return spring 14 and the elastic force of the recording paper 16 and the platen 15, respectively. The above-described point recording operation is repeated, and as the print head moves in the print line direction, dot matrix characters are recorded. The structure and operation of the print head of a dot matrix printer are as described above. Next, the structure and operation of the hammer drive mechanism of the line printer will be explained based on FIG. 2. In Figure 2, the approximately U-shaped iron core 1
02 is made of a magnetic material with high magnetic permeability and is fixed to a frame (not shown), and a coil 103 is wound around a lower leg portion 102a provided on the iron core 102.
The mover 104 is made of a magnetic material with high magnetic permeability, and has a collision surface 1 that collides with a limiting member 108, which will be described later.
A film of a titanium compound, that is, titanium carbide in this specific example, is formed on 04a by ion plating. Further, the movable element 104 is rotatably attached to a movable element shaft 105 fixed to the upper leg portion 102b of the iron core 102. The mover spring 106 is fixed to the frame (not shown) by biasing the mover 104 clockwise with a tension spring suspended between the frame (not shown) and the mover 104. The movable element 104 is pressed against the movable element stopper 107, and the movable element 104 is held at a standby position. Limited member 10
Reference numeral 8 denotes a member that determines the suction operation range of the movable element 104, and is fixed to a frame (not shown).
4 performs a suction operation and collides with the limiting member 108 immediately before colliding with the iron core 102. The above-mentioned iron core 102, coil 103, mover 1
04, the movable element shaft 105 and the movable element spring 106 are arranged in parallel for the required number of printing digits as a driving unit for driving a hammer 109, which will be described later. The left end of the rod-shaped hammer 109 is connected to the type drum 1, which will be described later.
The movable element abutting part 109 serves as a hammer surface 109a for printing the type 111a provided on the movable element 11, and the right end thereof abuts against the hammer abutting part 104b of the movable element 104.
b, and is supported by two parallel plate springs 110 fixed to a frame (not shown), and the parallel plate springs 11
It is configured to be pressed against the hammer contact portion 104b of the movable element 104 with an urging force of 0. A cylindrical type drum 111 is rotatably supported by a frame (not shown).
On the outer circumferential surface of 11, there are a plurality of different types of type 1.
11a is provided, and by constantly rotating the type drum 111 by a type drum driving means (not shown), different types of type characters 111a are sequentially passed in front of the hammer face 109a of the hammer 109. It is configured. A recording paper 112 is wound around the outer periphery of the type drum 111, and is configured to be intermittently conveyed by a recording paper feeding means (not shown) each time printing is completed line by line. The ink ribbon 113 is provided between the recording paper 112 and the hammer surface 109a of the hammer 109, and is configured to run in the printing line direction by an ink ribbon feeding means (not shown). Next, the action will be explained. When the coil 103 of the corresponding digit is excited by the printing command, an electromagnetic force acts on the movable element 104 corresponding to the excited coil 103.
The movable element 104 swings counterclockwise against the biasing force of the movable element spring 106 and collides with the limiting member 108 . As a result of the swinging, the corresponding hammer 109 is driven against the biasing force of the parallel plate spring 110, and prints the type 111a on the type drum 111 via the ink ribbon 113 and the recording paper 112. The shape of the type 111a on the type drum 111 is recorded on the recording paper 112 by this stamping. When the excitation to the coil 103 is cut off, the hammer 109 is activated by the parallel plate spring 11.
It returns to the standby position due to the biasing force of 0 and the resilient force of the type drum 111. In a line printer, printing is performed by performing the above recording operation line by line. The above explanation has clarified the structure and operation of the print head of a dot matrix printer and the hammer drive mechanism of a line printer, but in general, the electromagnet for the print head of a dot matrix printer has a high-speed response of 1KHz to 3KHz and a ~Billions of endurance cycles are required.
Furthermore, the electromagnets of line printers are not required to have the same high-speed response and durability as the above-mentioned dot matrix printers, but since the printing energy is greater than that of dot matrix printers, the impact when the movable element collides is large, and high durability is still required. In order to satisfy the above requirements, it is necessary to increase the durability of the components of the magnetic path without impairing their high magnetic permeability. In this specific example, both the printing head electromagnet and the hammer driving electromagnet use means of forming a film of titanium carbide on the mover, which is a component of the magnetic path, by ion plating. By using this method, the surface hardness of the mover becomes about 2000 Vickers hardness, and the thickness of the hardened layer is only 2μ.
Since it is approximately m, durability can be improved without impairing the high magnetic permeability of the mover. Note that if the limiting member is not a component of a magnetic path, the limiting member does not need to be a magnetic material, and there is a degree of freedom in selecting the material, curing method, etc., and it is not always necessary to form a film of a titanium compound by ion plating. There isn't.
Furthermore, when high-speed response is not required as in this specific example, the mover may be caused to collide directly with the iron core, and in such a case, a titanium compound film may be formed on the iron core as well by ion plating. In general, ion plating provides better adhesion to the base material than plating, allows for the deposition of highly hard materials such as titanium carbide, and allows for thinner surface hardening layers compared to carburizing and quenching. It has many advantages and can be said to be the most suitable hardening means for magnetic path components in electromagnets.

As is clear from the above explanation, the present invention is effective in improving the durability, high-speed response, and reliability of electromagnets, and is suitable for printing heads of dot matrix printers that require severe durability conditions as in this specific example. It is particularly effective when applied to an electromagnet for driving a hammer in a line printer.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a dot matrix printer print head, and FIG. 2 is a sectional view showing a hammer drive mechanism of a line printer. 2...Iron core, 4,104...Mover, 108...
...Limited parts.

Claims (1)

[Scope of Claims] 1. In an electromagnet including a movable element and a limiting member that limits the suction operation range of the movable element, a collision surface of the movable element with which the movable element and the limiting member collide; An electromagnet characterized in that a film of a titanium compound is formed on at least one of the collision surface of the limiting member by ion plating. 2. The electromagnet according to claim 1, wherein the limiting member is a component of a magnetic path. 3. The electromagnet according to claim 2, wherein the magnetic path forming member is an iron core.