JPH0581914U - Permanent magnet switch - Google Patents

Abstract

(57) [Summary] [Purpose] To obtain a permanent magnet switch that is more suitable for downsizing than a reed switch and does not require an external magnetic field source and has excellent impact resistance. [Structure] Cylindrical non-magnetic metal case 1, ring-shaped soft magnetic body 3 also serving as first soft magnetic contact part 6A, and one or a plurality of pieces insulated and fixed with glass 7 inside the ring-shaped soft magnetic body. It has a structure in which a magnet body 2 having a contact function is movably incorporated in a joint body with a base portion 8 composed of a second soft magnetic contact part 6B. The annular soft magnetic body 3 is joined to the opening of the cylindrical non-magnetic metal case 1 to seal the opening, and the magnet body 2 is attached to the first and second soft magnetic contact component sides. The effect of sucking into
Improves impact resistance.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a permanent magnet switch that operates by approaching and separating a magnetic body or a permanent magnet.

[0002]

[Prior Art]

 2. Description of the Related Art Conventionally, as a switch operated by magnetic force, a reed switch in which the tip portions of a pair of magnetic leads are enclosed in a glass tube is well known. This reed switch causes the tip of one magnetic lead to become the N pole and the S pole at the tip of the other magnetic lead by an external magnetic field to generate a magnetic attraction force against the elastic force of each magnetic lead. The ends of both leads are short-circuited to switch on.

[0003]

[Problems to be solved by the device]

 The reed switch, however, has the following drawbacks. (1) Since the structure is such that the pair of leads are led out from the glass tube in mutually opposite directions, the total length of the switch becomes long, and miniaturization is difficult. (2) A permanent magnet or electromagnet is required to operate the reed switch, and in order to generate an N pole at the tip of one magnetic lead and an S pole at the tip of the other magnetic lead, a reed switch is used. There are also many restrictions such as the direction of magnetic field application. (3) Since the tips of both magnetic leads are closed by an external magnetic field against the elastic force of the magnetic leads, it is difficult to increase the opening and closing speed of the contacts, and it is difficult to turn on and off large currents. Not suitable. Also, when a large current is passed, a magnetic field is generated by the magnetic wire itself, which hinders the opening and closing of the contacts. From this point as well, it can be said that it is not suitable for carrying a large current. (4) When the reed switch is switched off, the magnetic reed may vibrate due to shock and short circuit.

On the other hand, as a miniaturized magnetic switch, a fixed contact portion is provided on one surface of a case such as resin, and a movable contact body of a magnetic body is provided in the case so as to be vertically movable, and the movable contact body is provided outside the case. Japanese Patent Application Laid-Open No. 63-29424 proposes that the fixed contact portions are turned on and off by being driven by a permanent magnet. However, it is only the magnetic movable contact that moves inside the case, and a magnetic field generation source is required outside.

In view of the above points, an object of the present invention is to provide a permanent magnet switch which is more suitable for downsizing than a reed switch, and which does not require an external magnetic field generation source and has excellent impact resistance.

[0006]

[Means for Solving the Problems]

 In order to achieve the above object, the permanent magnet switch of the present invention comprises a cylindrical non-magnetic metal case, an annular soft magnetic body also serving as a first soft magnetic contact part, and an insulator inside the annular soft magnetic body. A magnet body having a contact function is movably incorporated in a joint body with a base portion composed of one or a plurality of second soft magnetic contact parts insulated and fixed by the above-mentioned annular soft magnetic body. Has a function of joining to the opening of the cylindrical non-magnetic metal case to seal the opening and to attract the magnet body to the first and second soft magnetic contact parts.

[0007]

[Action]

 In the permanent magnet switch of the present invention, a magnet body having a contact function is movably provided in a cylindrical non-magnetic metal case, and movement of the magnet body shorts or opens the soft magnetic contact parts attached to the case side. The switch is turned on and off. Therefore, the switch can be turned on and off by bringing a magnetic body close to the outside of the cylindrical non-magnetic metal case or moving the magnetic body close to the case away from the case, and an external magnetic field is not always necessary. Have advantages. In addition, the magnet body can maintain the switch-on state while being attracted by the magnetic force to the soft magnetic contact part itself and the annular soft magnetic body to which the contact part is insulated and fixed. Since it maintains the switch-off state, it has excellent shock resistance, and there is no risk of the state changing from on to off or from off to on due to impact. Also, one contact is provided on the annular soft magnetic body using the annular soft magnetic body that also serves as the first soft magnetic contact part, and then one or a plurality of second soft magnetic contacts are provided. Since the soft magnetic contact parts are configured by insulatingly fixing the parts inside the first soft magnetic contact part, the manufacturing is easier than when all the soft magnetic contact parts are provided inside the annular soft magnetic body. , The diameter of the ring-shaped soft magnetic material can be made smaller and a smaller diameter permanent magnet switch can be realized, or the diameter of the inner ring-shaped soft magnetic material can be increased to increase the diameter of the second soft magnetic contact part inside. By doing so, a permanent magnet switch suitable for a larger current can be realized. Further, since the annular soft magnetic body and the cylindrical non-magnetic metal case can be easily sealed and joined, the contact portion can be hermetically sealed, and a highly reliable structure can be easily realized.

[0008]

【Example】

 An embodiment of a permanent magnet switch according to the present invention will be described below with reference to the drawings.

1 and 2 show a first embodiment of the present invention. In these figures, 1 is a bottomed cylindrical non-magnetic metal case made of aluminum, nickel silver, copper, brass, stainless steel or the like, and inside the cylindrical permanent magnet 11 such as a rare earth magnet or a ferrite magnet. A magnet body 2 formed by depositing a good conductive metal material 12 such as gold, silver, nickel or copper by plating or the like is housed so as to be vertically movable. The annular soft magnetic body 3 made of iron, nickel alloy or the like has a lead / protrusion 5 integrally formed thereon, and the lead / protrusion 5 is coated with gold, silver, nickel, copper or the like to form a good conductive metal material 14A. The first soft magnetic contact part 6A is formed by depositing as a coating. Also, by depositing and forming a good conductive metal material 14B as a coating on both ends of the soft magnetic lead 4 formed of iron, nickel alloy or the like by gold, silver, nickel, copper plating or the like, the second soft It constitutes the magnetic contact part 6B. Then, the soft magnetic lead 4 is inserted into the inside of the ring-shaped soft magnetic body 3 that also serves as the first soft magnetic contact part 6A, and the glass 7 is filled inside the ring-shaped soft magnetic body 3 and is insulated in the state. The base portion 8 is formed by fixing it to the annular soft magnetic body 3. Here, the good conductive metal material 14A at the tip of the lead / protrusion 5 of the annular soft magnetic body 3 and the good conductive metal material 14B at the tip of the soft magnetic lead 4 are set to have the same height. The base portion 8 is fixed to the case 1 such that the tip portions of the first soft magnetic contact component 6A and the second soft magnetic contact component 6B face the magnet body 2. That is, the ring-shaped soft magnetic body 3 of the base portion 8 is press-fitted into the opening of the case 1 or is joined together by using press-fitting and welding to seal the case opening. Then, the insulating coating 17 is formed on the outer surface of the case 1 or an insulator is arranged.

The film forming treatment of the highly conductive metal materials 14 A and 14 B on the lead-cum-protrusion 5 and the soft magnetic lead 4 of the annular soft magnetic body 3 is usually performed after the soft magnetic lead 4 is fixed by the glass 7. The magnet body 2 has the same magnetizing direction as the moving direction of the magnet body. For example, the portion facing the soft magnetic contact parts 6A and 6B has an S pole and the opposite surface has an N pole.

In the configuration of the first embodiment described above, when the magnetic body 10 outside the case is separated from the case 1 as indicated by the solid line J in FIG. 1, the soft magnetic leads 4 that form the soft magnetic contact parts 6A and 6B. As a result of the S pole of the magnet body 2 being attracted to the body 5 of the lead / protrusion 5 and the annular soft magnetic body 3, the good conductive metal material 12 on the surface of the magnet body 2 becomes the soft magnetic contact point parts 6A, The good conductive metal materials 14A and 14B of 6B are brought into contact with each other with a constant contact pressure due to magnetic force, and as a result, the soft magnetic contact parts 6A and 6B are short-circuited by the magnet body 2 to be switched on. When the external magnetic body 10 is brought into close contact or close contact with the case 1 as shown by the phantom line K in FIG. The magnetic attraction force between the N pole of the magnet body 2 is superior, and as a result, the magnet body 2 is attracted by the external magnetic body 10 and comes into contact with the upper wall of the case to be in the switch-off state.

According to the configuration of the first embodiment, not only the soft magnetic lead 4 and the lead-cum-protrusion 5 but also the body portion of the annular soft magnetic body 3 contributes to the attraction of the magnet body 2, so that it is extremely shock-resistant. A permanent magnet switch with excellent properties can be realized. Further, the soft magnetic lead 4 is fixed to the annular soft magnetic body 3 having the projection 5 serving as a lead in an insulating state with the glass 7 to form the base portion 8, and then the base portion 8 is attached to the cylindrical nonmagnetic metal case 1. It can be mounted, is easier to manufacture than the case where a glass tube is sealed like a reed switch, and there is no risk of the magnet body 2 and the contact portion being deteriorated by heat. Further, the projection 5 also serving as a lead is integrally formed on the annular soft magnetic body 3 to form a first soft magnetic contact part, and the second soft magnetic contact part is formed inside the annular soft magnetic body 3 to form a second soft magnetic contact part. By forming the pair of soft magnetic contact parts 6A and 6B by insulatingly fixing the soft magnetic lead 4 of FIG. 1, the base portion 8 is manufactured rather than fixing the two soft magnetic leads inside the annular soft magnetic body 3. And the diameter of the annular soft magnetic body 3 can be reduced, and a permanent magnet switch with a smaller diameter can be realized. Alternatively, by making the diameter of the soft magnetic lead 4 large while keeping the diameter of the annular soft magnetic material 3 unchanged, a permanent magnet switch suitable for a larger current can be configured. Furthermore, if the magnet body 2 is formed by using a rare earth magnet having a high energy product (BHmax), a permanent magnet switch that can withstand an impact of several tens of G or more can be realized.

FIG. 3 is a partially enlarged view showing a second embodiment of the present invention. In this case, it is possible to secure good integration of the highly conductive metal material 18A, 18B such as gold, silver, nickel, copper or the like by caulking or the like to the tips of the lead-cum-protrusion 5 and the soft magnetic lead 4 of the annular soft magnetic body 3. The first and second soft magnetic contact parts 6A and 6B are configured. The rest of the configuration is similar to that of the first embodiment described above.

FIG. 4 shows a third embodiment of the present invention. In this case, the magnet body 2 has a structure in which a cylindrical body 21 of a good conductive metal is connected and fixed to the good conductive metal material 12 on the surface of the cylindrical permanent magnet 11. Then, the cylindrical body 21 integral with the magnet body 2 is fitted and contacted around the tip of the good conductive metal material 14B of the second soft magnetic contact point component 6B. The rest of the configuration is similar to that of the first embodiment described above.

In each of the above embodiments, the soft magnetic lead 4 constituting the second soft magnetic contact part is one, but a plurality of soft magnetic leads 4 are arranged and fixed inside the annular soft magnetic body 3. By constructing the parts, it is possible to arrange three or more contact parts on the entire surface of the case.

In each of the embodiments, it is also possible to employ a structure in which a permanent magnet is caulked with gold, silver, nickel, copper or another good conductive metal material and fixed by press fitting or the like as a magnet body.

Further, in each of the embodiments, a non-oxidizing gas (nitrogen gas, inert gas) is filled in the joined body of the cylindrical non-magnetic metal case and the base portion or a vacuum is applied to the magnet body and the contact parts. Adopting a structure that hermetically seals the inside of the bonded body, including the tip of the, is effective in extending the contact life.

Further, although the magnetic body outside the case is used to move the magnet body inside the cylindrical non-magnetic metal case, a permanent magnet is arranged outside the case to move the magnet body inside the case. You can also

Moreover, in the first embodiment, the insulating coating 17 is provided on the outer surface of the case 1. However, either one or both of the inner surface and the outer surface is provided with the insulating coating, or the insulator is arranged. May be.

[0020]

[Effect of the device]

 As described above, according to the permanent magnet switch of the present invention, the following effects can be obtained. (1) Since the contact pressure (contact pressure) between the magnet body and the soft magnetic contact parts fixed on the cylindrical non-magnetic metal case side is retained by the magnetic force, the spring parts required for conventional switches are completely unnecessary. Therefore, the structure is simple and the reliability is high. (2) The magnetic attraction force between the magnet body and the annular soft magnetic body in which the soft magnetic contact part is fixed with an insulator contributes to the increase of the contact pressure, and therefore the shock resistance is extremely excellent. Therefore, the problem of chattering does not occur. (3) Use a ring-shaped soft magnetic material having a projection that also serves as a lead as the first soft magnetic contact component, and fix the soft magnetic leads to be the second soft magnetic contact component inside in a mutually insulated state. By constructing the base part, it is possible to provide one contact on the annular soft magnetic body, rather than providing all the contacts by fixing a plurality of soft magnetic leads inside the annular soft magnetic body. In addition to facilitating the manufacture of the base portion, the diameter of the annular soft magnetic material can be reduced, and a permanent magnet switch with a smaller diameter can be realized. Also, by increasing the diameter of the soft magnetic lead while keeping the diameter of the annular soft magnetic material unchanged, a permanent magnet switch suitable for a larger current can be realized. (4) The magnet body can move and rotate in the case, and as a result, the contact position of the magnet body with respect to the contact parts fixed to the case is not always constant. This means that the contact part on the magnet side has a longer life. (5) The contact parts fixed to the case do not need elasticity and can be placed on one side of the case. Therefore, unlike the conventional reed switch, the total length does not become long and it is suitable for downsizing. (6) The magnetic body inside the case can be operated by the magnetic body outside the case, and a magnetic field generation source such as a permanent magnet or an electromagnet is not required outside. This means that it has a wider range of applications than lead switches and the like.

[Brief description of drawings]

FIG. 1 is a front sectional view showing a first embodiment of a permanent magnet switch according to the present invention.

FIG. 2 is an external view of the same.

FIG. 3 is a partially enlarged sectional view showing a second embodiment of the present invention.

FIG. 4 is a front sectional view showing a third embodiment of the present invention.

[Explanation of symbols]

 1 Cylindrical non-magnetic metal case 2 Magnet body 3 Annular soft magnetic body 4 Soft magnetic lead 5 Lead-combined protrusion 6A, 6B Soft magnetic contact part 7 Glass 8 Base part 10 Magnetic body 12A, 12B, 18A, 18B Good conductive metal material

Continued Front Page (72) Shigeo Saito Inventor, 13-1 Nihonbashi, Chuo-ku, Tokyo TDK Corporation

Claims (7)

[Scope of utility model registration request] 1. A cylindrical non-magnetic metal case, an annular soft magnetic body also serving as a first soft magnetic contact member, and one or a plurality of first and second insulating soft magnetic bodies which are insulated and fixed by an insulator. In the joint body with the base part consisting of the soft magnetic contact parts of 2,
A magnet body having a contact function is movably incorporated, and the annular soft magnetic body is joined to the opening of the cylindrical non-magnetic metal case to seal the opening, and the magnet body is A permanent magnet switch which attracts to the first and second soft magnetic contact parts. 2. A good conductive metal material is adhered or formed as a coating on at least the tip end portions of the first and second soft magnetic contact parts so as to be freely contactable with the magnet body.
Permanent magnet switch described. 3. The permanent magnet according to claim 1, wherein a good conductive metal material is adhered or adhered as a coating on at least a surface of the magnet body that is in contact with at least the first and second soft magnetic contact parts. switch. 4. The permanent magnet switch according to claim 1, wherein a non-oxidizing gas is enclosed in the joined body of the cylindrical non-magnetic metal case and the base portion. 5. The permanent magnet switch according to claim 1, wherein an insulating coating or an insulator is provided on either or both of an inner surface and an outer surface of the cylindrical non-magnetic metal case. 6. The permanent magnet switch according to claim 1, wherein the insulator fixed to the inside of the annular soft magnetic material is glass. 7. The permanent magnet switch according to claim 1, wherein the magnetizing direction of the magnet body is the same as the moving direction of the magnet body.