JP2673178B2 - Monostable Latching Solenoid - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Construction of the Invention] (Field of Industrial Application) The present invention relates to a small monostable latching solenoid. (Prior Art) In recent years, a turbine type gas meter 1 as shown in FIG. 5 has been proposed in order to reduce the size and performance of a gas meter. In this turbine gas meter 1, an impeller chamber 3 is formed in a casing 2, and an impeller 4 that rotates by the inflow of gas is arranged in the impeller chamber 3. Then, a small nozzle 5 and a large nozzle 6 are formed in the impeller chamber 3, a monostable latching solenoid 7 is provided for the large nozzle 6, and the plunger 8 is driven to open and close.
The amount of gas flowing into the impeller chamber 3 is switched between a large flow rate and a small flow rate so that the gas usage amount can be measured in a wide range. By the way, in the turbine gas meter 1 as described above, it is desired that the size of the monostable latching solenoid 7 for opening and closing the large nozzle 6 is small. However, when such a solenoid 7 is downsized, its suction force becomes small, the opening / closing force of the large nozzle 6 becomes weak, and accurate measurement cannot be performed. Therefore, in the conventional monostable solenoid 7, a relatively small solenoid having the shape shown in FIGS. 6 and 7 was used. In this conventional latching solenoid 7, a thin bobbin pipe 10 made of magnetic metal is provided in the center of a magnetic frame 9 having a substantially U-shaped cross section.
In the bobbin pipe 10, a fixed iron core 12 is caulked and fixed to the bottom portion 11 of the frame 9, and a plunger 8 is inserted to face the fixed iron core 12 so as to approach and separate from the fixed iron core 12. The coils 13 are wound around the bobbin pipe 10 in an orderly and multiple layers. In addition, 14 is a rare earth permanent magnet, 15 is a magnetic field line holding plate, 16 is a coil holding plate, 17 is a caulking fixing part, 18
Is a two-wire lead wire. (Problems to be Solved by the Invention) However, in such a conventional monostable latching solenoid 7, the width W _{0 of the} frame 9 and the diameter D _{0 of the} coil 13 are
The height H ₀ of the frame 9 and the length l _{0 of the} coil 13 are larger than those of, and the latching solenoid of the required suction force is required unless the conditions l ₀ / D ₀ > 1.5 H ₀ / W ₀ > 1.5 are set. It was thought that 7 could not be obtained. Therefore, in this conventional monostable latching solenoid 7, the width W _{0 of the} frame 9 is approximately 14 mm and the height H _{0 is} approximately 35 mm in order to set the attraction force when the stroke of the plunger 8 is approximately 3 mm to approximately 100 g. The coil 13 had a diameter D ₀ = about 15 mm and a length l ₀ = about 28 mm. However, in this way, the length l ₀ is increased with respect to the diameter D ₀ of the coil 13, and at the same time, the height H _{0 is} increased with respect to the width W _{0 of the} frame 9.
If the height is increased, the overall shape becomes large, and when the large nozzle 6 is opened and closed by being housed in the casing 2 of the gas meter 1, there is a problem that the gas meter 1 itself becomes large. The present invention has been made in view of such conventional problems, and the required suction force can be obtained even if the length of the coil is shortened with respect to its diameter and the height of the frame is also reduced with respect to its width. It is an object of the present invention to provide a small monostable latching solenoid that can be obtained and has a predetermined suction force. [Structure of the Invention] (Means for Solving the Problems) According to the present invention, a metal bobbin pipe is arranged in a central portion of a frame bent in a substantially U-shaped cross section, and the frame is provided in the bobbin pipe. A fixed iron core is caulked and fixed to the bottom of the bobbin pipe, and a plunger is inserted into the fixed iron core so as to be able to be moved close to and separated from the fixed iron core, and a conductor is closely wound around the outer circumference of the bobbin pipe to form a coil. Both ends are held by holding plates provided on the bobbin pipe, and permanent magnets are attached to the inner side surfaces of the opening of the frame, which face each other, and monostable latching in which magnetic force line holding plates are arranged between these permanent magnets. In the solenoid, the holding plate has a coil diameter of 1 when the coil length is 1.
Even if the conductor wire is tightly wound around the outer circumference of the bobbin pipe until it becomes, it is formed with a thickness that can hold both ends of the coil.
The magnetic path constituent members such as the frame, the plunger, and the fixed iron core are annealed. (Operation) In the monostable latching solenoid of the present invention, the magnetic path is made of a magnetic material whose magnetic resistance is reduced by annealing, and when the coil length is 1, the diameter of the coil is 1 Until it becomes a tightly wound conductor wire, a holding plate with a thickness that can hold both ends of the coil is provided, so a tightly wound coil with a large number of turns can be used. Even if the length is shortened, the required suction force can be applied, and the size can be reduced while maintaining the predetermined suction force. (Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings. 1 and 2 show one embodiment of the present invention. The frame 19 is bent and formed in a substantially U-shaped cross section, and has a thickness t ₁ of about 1.4 mm, a width W ₁ of about 18 mm, and a height H ₁ of about 2 mm.
5mm. This frame 19 is obtained by bending and forming a rolled steel plate by press forming, and by bending in a direction perpendicular to the rolling direction, generation of cracks is suppressed as much as possible, and the magnetic path cross-sectional area is widened. There is. The ratio of the width W ₁ to the height H ₁ of this frame 19 is W ₁ : H ₁ = about 1:
The frame size is 1.4, and the outer dimensions of the frame 19 are relatively small. A mounting hole 21 is formed in the center of the bottom portion 20 of the frame 19, and a fixed iron core 22 is caulked and fixed in the mounting hole 21. In this caulking work, the mounting hole 21
By crushing the caulking protrusion 23 that is inserted through to the back side, the portion of the caulking protrusion 23 is brought into complete contact with the mounting hole 21, and it is considered that there is no magnetic gap. Rare earth permanent magnets on the inner surface of the open end of the frame 19
24 is stuck. The coil portion 25 is a metal bobbin pipe with a relatively thin wall.
A coil holding plate 28 having a relatively large thickness at the expanded portion 27 at one end of 26
This coil holding plate 28 is used as one guide, and a coil holding plate 29 having a relatively large thickness is arranged at the other end of the bobbin pipe 26, and both coil holding plates 28, 29 are used as pressing members from the outside. While supporting it, rotate it to guide the bobbin pipe 26
The coil 30 is formed by winding the coil 30 in multiple layers. When the length l ₁ of the coil 30 is set to 1, the thickness of the coil holding plates 28 and 29 is set even if the conductor wire is wound around the bobbin pipe 26 until the diameter D _{1 of the} coil 30 becomes at least 1. The thickness is set so that both ends of the coil 30 can be held. The coil 30 has a diameter D ₁ = about 20 mm, a length l ₁ = about 20 mm, and l ₁ : D ₁ = about 1: 1. The coil portion 25 is inserted into the frame 19 from the opening side, and one end of the bobbin pipe 26 is fitted and assembled to the fixed iron core 22. Then, set the plunger in the bobbin pipe 26.
31 is inserted. Further, a magnetic force line holding plate 32 is assembled on one coil holding plate 28 side of the coil portion 25, and both end edges of the magnetic force line holding plate 32 are fixed to the end face of the opening of the frame 19 via permanent magnets 24. . The magnetic force line holding plate 32 holds the plunger 31 movably. The process of assembling the monostable latching solenoid having such a structure will be described below. First, a frame 19 having a substantially U-shaped cross section is formed, and a fixed iron core 22 is caulked and fixed in a mounting hole 21 of the bottom 20. This caulking process is performed accurately, and the caulking projection 23 is smashed until it comes into close contact with the mounting hole 21. Then, after this, it is annealed by being left under a temperature condition of about 210 ° C. for about 6 hours. By this annealing treatment, the magnetic resistance of the member is significantly improved and the magnetic flux density of the magnetic circuit is reduced to
Can be improved by 20%. The temperature conditions of this annealing treatment are not particularly limited to the above, and it is possible to anneal under high temperature conditions within a short time. Further, a coil holding plate 28 made of a synthetic resin having a high rigidity such as a relatively thick bakelite plate is attached to the expanded portion 27 at one end of the bobbin pipe 26 made of a relatively thin metal wall.
The same coil holding plate 29 is provided on the opposite end of the bobbin pipe 26.
Place. Then, between the coil holding plates 28, 29 on both sides, the coil 30 is constructed by winding the conductor wire around the outer circumference of the bobbin pipe 26 in multiple layers. The coil portion 25 thus obtained is assembled to the fixed iron core 22 of the frame 19 that has been annealed. Next, the rare earth permanent magnets 24, 24 are attached to the inner surface of the opening side end of the frame 19, and the magnetic force line holding plate 32 is attached so as to be in close contact with the permanent magnets 24, 24. The operation of the monostable latching solenoid having the above structure will be described below. This monostable latching solenoid is used with the circuit configuration shown in FIG. 3 and the mechanical configuration shown in FIG. Referring first to describe a magnetic circuit, the switch SW _1, SW ₂ is provided with respect to the DC power source E, the two switches SW _1, SW ₂ are connected to both ends of the coil 30. Then, the recovery spring 33 is attached to the protruding end of the plunger 31. Therefore, with the plunger 31 protruding,
When one switch SW ₁ is connected to the (+) side of the DC power supply E and the other switch SW ₂ is connected to the (−) side of the DC power supply E and the coil 30 is energized with pulsed power, 31 is attracted to the fixed iron core 22. As a result, one end of the plunger 31 is attracted to the fixed iron core 22. After this, even if the exciting current to the coil 30 is cut off, the permanent magnet 24 having a strong magnetic force, the frame 9, the fixed iron core 22, the plunger 31, and the magnetic field line holding plate 32.
The magnetic circuit formed by and holds the attracted state. Then, when the switch SW ₂ is connected to the (+) side of the DC power supply E and the switch SW ₁ is connected to the (−) side of the DC power supply E to give pulse power to the coil 30, Is reverse-excited, the reverse-excitation magnetic force of the coil 30 cancels out the magnetic force of the permanent magnet 24, and the force of the restoration spring 33 causes the plunger 31 to project to its original state. Now, for the monostable latching solenoid of the above-described embodiment that operates in this way, the suction force of a stroke of 3 mm is
The results of comparison with those of the conventional example were as follows. table. Comparative voltage condition of attractive force characteristics This example Conventional example 2.0V 85g 86g 2.5V 109g 110g 3.0V 135g 137g As is clear from the above results, in the conventional magnetic circuit, the coil diameter D ₀ and length l ₀ Although the ratio is set to l ₀ / D ₀ > 1.5, in the case of this embodiment, the same suction force as in the conventional case can be realized even if l ₁ / D ₁ = about 1.0. Since the suction force is not reduced even if the length is shortened with respect to the diameter of the coil in this way, the outer dimensions of the coil can be made smaller, and as a result, the frame can be made smaller and the latching The size of the entire solenoid can be reduced. In the above embodiment, the ratio of coil diameter to length l ₁ / D
₁ = about 1.0, but this ratio is not particularly limited as long as it is about 1.0 or less. Also, the overall size is not limited to that of the embodiment. Further, needless to say, the attraction force of the plunger can be further improved by using the electromagnetic soft iron material for the fixed iron core and the frame. [Effect of the Invention] As described above, according to the present invention, since the annealed material is used as the magnetic circuit constituent member, the magnetic resistance of the magnetic circuit is small, and accordingly, the magnetic force loss is reduced and a large plunger attraction force is obtained. Obtainable. When the length of the coil in the axial direction is set to 1, a holding plate having a thickness capable of holding both ends of the coil is provided even when the conductor wire is closely wound until the diameter of the coil becomes 1. It is possible to use a tightly wound coil with a large number of windings, and it is possible to apply a required suction force even if the length corresponding to the diameter of the coil is shortened.
The overall size can be reduced without lowering the plunger suction force. That is, the most compact coil having a diameter-to-length ratio of 1 to 1 enables the overall size reduction.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of an embodiment of the present invention, FIG. 2 is a sectional view of the above embodiment, FIG. 3 is an electric circuit diagram of the above embodiment, and FIG.
FIGS. 5A and 5B are explanatory views of the operation of the above embodiment, FIG. 5 is a schematic sectional view of a turbine gas meter, FIG. 6 is a perspective view of a conventional example, and FIG. 7 is a sectional view of the conventional example. is there. 19 …… Frame, 22 …… Fixed iron core 23 …… Caulking protrusion, 24 …… Permanent magnet 25 …… Coil part, 26 …… Bobbin pipe 28,29 …… Coil holding plate 30 …… Coil, 31 …… Plunger D ₁ …… coil diameter, l ₁ …… coil length W ₁ …… frame width, H ₁ …… frame height

Claims (1)

(57) [Claims] A metal bobbin pipe is arranged in the center of the frame bent into a substantially U-shaped cross section, and a fixed iron core is caulked and fixed to the bottom of the frame in the bobbin pipe, and a close opening is made to the fixed iron core. A plunger is inserted into the bobbin pipe in a detachable manner, and multiple conductors are closely wound around the outer circumference of the bobbin pipe to form a coil, and both ends of the coil are held by holding plates provided on the bobbin pipe, and the opening of the frame is opened. Is a monostable latching solenoid in which permanent magnets are attached to the inner surface portions of each of the two facing each other, and magnetic force line holding plates are arranged between these permanent magnets, wherein the holding plate has a coil length of 1 In such a case, even if the conductor wire is wound tightly around the outer circumference of the bobbin pipe until the coil diameter becomes 1, it is formed to have a thickness that can hold both ends of the coil. A monostable latching solenoid in which a magnetic path forming member such as an iron core is annealed. 2. The monostable latching solenoid according to claim 1, wherein both the diameter and the length of the coil are 20 mm.