JPS62163280A - Magnetic plug - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] 〔Technical field〕 The present invention relates to a magnetic plug.

[Background technology]

A magnetic plug generally has a structure as shown in FIGS. 8 and 9. That is, a container 3 is constructed by combining a body 1 and a cover 2 and connecting them with screws 3a.
A permanent magnet (hidden and invisible) with suction plates 5 on both left and right sides is disposed inside, and the ends of the suction plates 5 protrude from the container 3. A contact spring 4a having a contact point 4b at its tip is placed in the container 3 with its tip facing the connection hole 4 provided in the container 3. In the figure, 4C is a lead wire. In this magnetic plug, the end of the suction plate 5 is attracted to an iron piece 7a provided at the connection part 6a of an electric appliance 6 such as an electric heater, and the attraction force is used to draw the end of the suction plate 5 into the connection hole 4 of the container 3. Connect the contact 4b with the conductive rod 7
b to make an electrical connection.

However, conventional magnetic plugs are positioned simply by fitting the contact spring into a groove provided in the container, so the contact spring may wobble due to a gap being created between the groove and the contact spring. The fixed position becomes unstable and the contact pressure of the contact spring changes, or
There was a problem in that the contact pressure varied from plug to plug.

[Purpose of the invention]

The present invention was made in order to solve such problems, and an object of the present invention is to provide a magnetic plug with less change and variation in contact pressure.

[Disclosure of the invention]

In order to achieve the above object, the present invention includes a permanent magnet having suction plates on both left and right sides in a container configured by combining a body and a cover, with the ends of the suction plates protruding outside the container. The magnetic plug is stored in a state in which a contact spring having a contact point at the tip faces an opening at the tip of the container, the contact spring having a protrusion at the tip. The body and the cover are positioned by holding a rising piece on the side, the side part of the contact spring being press-fitted and the tip of the protrusion being crushed, and the body and cover are brought together and positioned. The gist of this is a magnetic plug.

The present invention will be explained in detail below.

1 to 3 show a magnetic plug according to the present invention. As shown in the figure, this magnetic plug has a body 1 that is connected with a screw 3a to form a container 3.
and a cover 2, a magnet block 8 disposed inside the container 3 and two contact springs 9. The body 1 has a recess 1a,
lb and lc are arranged side by side. The magnet block 8 has suction plates 11 arranged on both sides of the permanent magnet 100, and is arranged in the recess 1b with the tip of the suction plate 11 protruding from a hole 12 provided on the front surface of the container 1. ing. The contact spring 9 is a plate body 9 whose width direction is horizontal.
A contact point 14 is provided on the front surface of a bent piece 13 formed by vertically bending the front end of the plate 9a. The intermediate portion of the plate body 9a is bent into a “<” shape, and a terminal portion 15 to which the lead wire 4c is connected is fixed to the base portion by a tab swage 16. Standing pieces 17 are provided on both sides of the terminal portion 15, and protrusions 17a are provided at the upper ends of the rising pieces 17 on both sides. As the material for the rising piece 17, for example, Furtic is used, but the material is not limited thereto. Vertical sections a18 into which the rising pieces 17 are press-fitted are provided on both side walls of the recess 1a, and a recess (dowel relief) 19 into which the lower end of the dowel caulking 16 is inserted is provided at the bottom.

Further, on both front side walls of the recess 1a, there are provided a protrusion 1d that serves as a left-right rest for the contact spring 9, and a recess 1e that serves as a relief portion to prevent the tip of the contact spring 9 from hitting. The recess 1c is also similar to the recess 1a. At a position above the recesses 1a and lc on the ceiling surface of the cover 2, a pressing portion (pressing rib) 20 that projects downward is provided. The contact spring 9 is inserted into the recess 1a or 1c, and the rising piece 17 is press-fitted into the vertical groove 18, and the tip of the protrusion 17a of the rising piece 17 touches the holding part 20.
The body 1 and the cover 2 are brought together so as to be crushed, and are positioned and fixed. And contact point 14
is made to look out from the connection hole 4.

In this magnetic plug, the rising piece provided on the side of the contact spring is press-fitted and fixed, and the protruding tip of the rising piece is held down with a cover so as to be crushed.
Since the contact spring is pressed against the body, the contact spring does not wobble and the fixed position is stable.

Therefore, changes and variations in the contact pressure are small. In the above embodiment, the rising pieces are provided on both sides of the contact spring, but they may be provided only on one side. Both sides of the contact spring are press-fitted, but only one side may be press-fitted and fixed. Also, the rising piece is press-fitted, but
A protrusion may be provided on the side of the contact spring separately from the rising piece, and this protrusion may be press-fitted and fixed. The number of protrusions provided on the rising piece is not limited to two.

〔reference〕

Note that if a contact such as a contact spring is provided as described here, there is less risk that the contact will loosen and rotate or that the temperature of the contact installation portion will rise.

Contacts are generally made by drilling a hole in a metal material (buff material) that serves as a contact spring, and then passing a wire made of silver or the like through this hole.
It is installed by caulking wire rods. However, due to variations in the crimping force during crimping, the contacts may become loose, causing the contacts to rotate or the temperature at the contact location to rise.

However, if the contacts are provided in the following manner, this problem can be prevented.

Here, a case where a contact point is provided on the above-mentioned contact spring will be described, but it is not limited to a case where a contact point is provided on the contact spring. As shown in FIG. 4, a through hole 21 is made in the rising piece 13 of the plate body 9a which becomes a contact spring.
A recess 22 is provided around 1. Next, through hole 21
Insert a contact wire made of silver or the like into the holder and caulk the wire.

Then, as shown in FIG. 5, the contact material enters the recess 22 on the back surface of the contact 14, so even if the crimping force varies somewhat, there is no risk that the contact 14 will loosen and rotate. In addition, since the contact 14 is less likely to loosen and the contact area between the back surface of the contact 14 and the plate 13 is increased, the risk of the temperature rising at the contact installation portion is greatly reduced.

In the example shown in FIG. 4, a rectangular recess is provided around the through hole 21, but the shape of the recess is not limited to this. For example, as shown in FIG. 6, a circular recess 23 may be provided around the through hole 21.

Further, the number of recesses is not particularly limited, and the installation position and the arrangement relationship between the recesses are also not particularly limited as long as they are located on the back side of the contact.

In FIGS. 5 and 6, the same numbers as in FIG. 4 indicate the same items.

If the height position of the contact spring is determined in the following manner, the range of variation in contact pressure will be reduced.

Conventionally, as shown in FIG. 8, the height position of the contact spring 4a was determined by bringing the bottom surface (straight portion) of the contact spring 4a into contact with the bottom surface of the body 1. However, in this case, since the contact area between the contact spring 4a and the body 1 is large, there is a possibility that the height position of the contact spring 4a will be influenced by the height of the bottom surface of the body 1, etc. There was a problem in that the width of pressure variation became large.

Therefore, as shown in FIG. 7, the recess 1 of the body
A or the bottom of the IC (see FIG. 1) is provided with a protrusion 24 extending in the width direction, and the bottom of the contact spring 9 is brought into contact only with the upper end of the protrusion 24, so that the contact spring 9 and the body 1 are connected to each other. Make a line contact or a very small area of contact. Then, if the height of the protrusion 24 is set accurately, the height position of the contact spring 4a can be accurately positioned, and the range of variation in contact pressure is reduced.

In FIG. 7, the same numbers as in FIGS. 1 to 3 indicate the same parts.

〔Effect of the invention〕

The magnetic plug according to the present invention includes a permanent magnet having suction plates on both left and right sides, which is housed in a container configured by combining a body and a cover, with the ends of the suction plates protruding outside the container. and a contact spring having a contact point at the tip thereof is housed with the contact point facing the opening at the tip of the container,
The contact spring has a rising piece on the side with a protrusion at the tip, and the side of the contact spring is press-fitted and fixed, and the tip of the protrusion is crushed so that the body and cover are brought together and positioned. Because of this, there are fewer changes and variations in contact pressure.

[Brief explanation of drawings]

Fig. 1 is an exploded perspective view of one embodiment of the magnetic plug according to the present invention, Figs. 2 and 3 are explanatory diagrams of the internal structure of the magnetic plug, and Figs. 4 to 6 are installation of contacts. An explanatory diagram of an example, FIG. 7 is an explanatory diagram of an example of installation of a contact spring,
FIGS. 8 and 9 are explanatory diagrams of conventional magnetic plugs. ■...Body 2...Cover 3...Container 9.
...Contact spring 10...Permanent magnet 11...Attraction plate 14...Contact 17...Rising piece 17a.
...Protrusion Agent Patent Attorney Takehiko Matsumoto Figure 2/\, Figure 4 Figure 5 Figure 6

Claims (2)

[Claims] (1) A permanent magnet with suction plates on both left and right sides is housed in a container constructed by combining a body and a cover, with the ends of the suction plates protruding outside the container, and A magnetic plug in which a contact spring having a contact point is housed with the contact point facing the opening at the tip of the container, the contact spring having a rising piece with a protrusion at the tip on the side, The side part of the spring is press-fitted and the tip of the protrusion is crushed,
A magnetic plug characterized by a body and a cover that are aligned and positioned. (2) The magnetic plug according to claim 1, wherein the side portion of the contact spring is press-fitted and fixed by a rising piece being press-fitted into a recess provided in the container.