JPH0145064Y2 - - Google Patents

Description

[Detailed description of the invention] [Technical field to which the invention pertains] The present invention relates to an auxiliary contact device having an auxiliary contact that operates in conjunction with a movable contact of an electromagnetic contactor body.

Magnetic contactors are often used to start and stop motors that are frequently opened and closed, but in addition to movable contacts, these magnetic contactors often require auxiliary contacts, and the number of these contacts cannot be controlled. Since it differs depending on the target, it is desired that auxiliary contacts can be easily added and replaced. For this purpose, the auxiliary contact device is formed separately from the electromagnetic contactor body and is detachably attached to the electromagnetic contactor body.

[Prior art and its problems]

This type of conventional device is shown in FIGS. 1 and 2, and FIG. 1 is a side sectional view of the auxiliary contact device.
FIG. 2 is an assembled exploded view of the electromagnetic contactor body and the auxiliary contact device.

The auxiliary contact device 4 for an electromagnetic contactor includes fixed contacts 5 and 6 provided in pairs on the upper and lower sides, bridge-type movable contacts 7 and 8 provided corresponding to the fixed contacts 5 and 6, respectively. Movable contact support 9, base 10a and cover 10 that house these
Case 10 consisting of b is the main component.
Each of the fixed contacts 5 and 6 is held by being fitted into a recess formed in the base 10a of the case 10, and a fixed contact is attached to one end of each, and terminal screws 11 and 12 are provided at the other end. . Movable contacts 7, 8 with movable contacts attached to each fixed contact
is supported by a movable contact support 9 as follows. In other words, the movable contact support 9 made of insulating material is
It is placed in the empty space of the base 10a of the case 10, and a columnar projection 9a is provided on one side thereof for connection to a movable contact support in the electromagnetic contactor main body or a movable contact support in the preceding auxiliary contact device. This protrusion 9a
A hole is provided on the opposite side of the projection 9a into which a columnar projection of the movable contact support of the next stage having the same size as the projection 9a is fitted. Further, the body of the movable contact support 9 is provided with rectangular through holes for attaching the movable contacts 7 and 8. Movable contacts 7 and 8 are inserted into the lower and upper sides of this through hole, respectively, with their contacts protruding from both sides of the body, and a coil spring 13 is inserted between the two contacts 7 and 8. , 8 are compressed and inserted in order to reduce the impact when they collide with the contacts of the fixed contact. The case 10 has a window 1 for penetrating the pillar-like projection of the next stage of movable contact support.
0c and a connecting screw through hole 10d are provided. In order to additionally attach an auxiliary contact device to the electromagnetic contactor main body 1, the electromagnetic contactor main body 1 is attached as shown in FIG.
A window 1b for connecting the movable contact support in the electromagnetic contactor main body 1 and a movable contact support in the auxiliary contact device and a screw hole 1c for mounting the auxiliary contact device are provided on both sides 1a of the electromagnetic contactor body 1.

To attach the auxiliary contact device 4 to the electromagnetic contactor body 1, insert the columnar projection 9a of the movable contact support 9 of the auxiliary contact device 4 into the window 1b of the electromagnetic contactor body 1 as shown by the arrow in FIG. At the same time, the screw 14 is passed through the screw hole 10d of the auxiliary contact device 4 and screwed into the screw hole 1c of the electromagnetic contactor body 1. Note that numeral 2 is a terminal of the main contactor.

In addition, as another conventional device, an auxiliary contact device 4 is provided on both sides 1a of the electromagnetic contactor main body 1 as shown in FIG.
It is also known that a hook-shaped engagement protrusion 15 provided on the auxiliary contact device 4 engages with a window 1d provided in the auxiliary contact device 4, thereby simplifying the attachment of the auxiliary contact device 4.

By the way, in such an auxiliary contact device 4, wear powder is generated due to friction between the movable contact support 9 and the case 10, and friction between the movable contacts 7 and 8 and the movable contact support 9. There is a drawback that abrasion powder adheres to the contacts of each contact, resulting in poor contact between the contacts. In particular, since the auxiliary contact circuit is often connected to a low-voltage control power supply circuit, the influence of wear particles is large. In addition, in order to reduce the contact resistance between the fixed contact and the movable contact in an auxiliary contact device, it is necessary to apply sufficient contact pressure through a coil spring, but when a large number of auxiliary contact devices are installed, the movable contact support moves. Since the contact pressure is attenuated, there is a problem in that sufficient contact pressure cannot be obtained and the number of auxiliary contact devices that can be installed is limited.

In order to solve this problem, it is known that a reed switch is used and the lead piece of this reed switch is connected to the terminal of the auxiliary contact. The disadvantage is that the shape of the auxiliary contact device must be changed in order to connect it to the terminal of the auxiliary contact device, and the cost increases due to the mold cost of the auxiliary contact device.

[Purpose of invention]

It is an object of the present invention to provide an auxiliary contact device for an electromagnetic contactor that eliminates the drawbacks of conventional devices, is not affected by abrasion powder, has a simple structure, and is easy to assemble.

[Key points of the idea]

The main points of the present invention are an auxiliary contact case attached to the electromagnetic contactor body, a movable rod housed in the auxiliary contact case and connected to the movable contact support of the electromagnetic contactor body and having a permanent magnet fixed thereto, and the auxiliary contact case. In an auxiliary contact device for an electromagnetic contactor, the reed switch is connected to the terminals of at least two sets of auxiliary contacts fixed to a contact case and operates according to the approach and separation of the permanent magnet, wherein the reed switch is mounted on a printed board. Attachment: An elastic contact piece for connecting the reed switch and the terminal of the auxiliary contact is attached to the printed board, and the printed board is mounted inside the auxiliary contact case. By using a reed switch, it is not affected by wear particles.
Furthermore, by attaching the reed switch and the elastic connecting piece for connecting the reed switch and the terminal of the auxiliary contact to the printed board, the structure is simple and assembly is easy.

[Example of idea]

Embodiments of the present invention will be described in detail based on the drawings. 4 and 5 show one embodiment of the present invention, FIG. 4 is a side sectional view of the auxiliary contact device, and FIG. 5 is a sectional view taken along line A-A in FIG. Components that are the same as those shown in the figures through FIG. 3 are designated by the same reference numerals.

In the figure, the auxiliary contact device 4 is shown again to be attached to the electromagnetic contactor main body, and this auxiliary contact device 4 includes an auxiliary contact case 10 consisting of a base 10a and a cover 10b, and a space 10e in the base 10a of this auxiliary contact case 10. A movable rod 91 that is housed in the housing and has a columnar projection 91a, a permanent magnet 25 fixed to the movable rod 91 (see FIG. 5), and two reed switches 2 that operate when the permanent magnet 25 approaches or separates.
3, 24, each pair of auxiliary contact terminals 21 fitted into the base 10a of the auxiliary contact case 10;
21, 22, 22 and each reed switch 2
Elastic contact pieces 33, 33 and 34, 34 electrically connect the respective lead pieces 3, 24, and a print to which each of the reed switches 23, 24 and the elastic contact pieces 33, 33, 34, 34 are attached. This is the main component of the plate 31. Contact portions 21a, 21a of the terminals 21, 21 of the auxiliary contacts
are the contact portions 33 of the elastic contact pieces 33, 33, respectively.
The contact portions 22a, 22a of the terminals 22, 22 are in elastic contact with the elastic contact pieces 3a, 33a, respectively.
It is in elastic contact with the contact portions 34a, 34a of No. 4, 34. Auxiliary contact terminals 21, 21 and 22, 2
2 may use the conventional fixed contact shown in FIG.
If necessary, surface treatment such as silver or gold plating may be applied to a and 34a. Terminal screws 11, 11 and 12 are provided at one end of the terminal of each of the auxiliary contacts, respectively.
12 is installed.

The printed board 31 is located in the recess 10e of the base 10a.
In particular, it has a size that matches the recess in the center and is fitted into the recess for installation. 6A shows the state in which this printed board 31 is removed from the base 10a.
and FIG. 6B. As is clear from FIGS. 6A and 6B, each reed switch 2
3 and 24 are holes 31a formed in the printed board 31,
31a, and each lead piece is soldered to a conductor on the printed board 31. Each lead piece 23a of the reed switch 23 and the printed board 3
The elastic contact pieces 33, 33 are electrically connected to each lead piece 24a of the reed switch 24 through the conductor of the printed board 31, respectively. It is made of an elastic material such as phosphor bronze or stainless steel and is formed into a U-shape. Each elastic contact piece 33, 33, 3
4 and 34 have the same shape, and one elastic contact piece 33 is shown in FIGS. 7A and 7B. As is clear from FIGS. 7A and 7B, one end of the elastic contact piece 33 is extruded into a spherical shape to form a contact portion 33a, and the other end is divided into three legs, with the central leg bent inward and raised. At the same time, each leg is soldered to a printed board 31. The elastic contact piece is firmly fixed to the printed board 31 by dividing the other end of the elastic contact piece into a plurality of legs, bending the appropriate legs and attaching them to the printed board 31. The reed switch 23, 2
A magnetic pole piece 26 made of soft iron or the like is arranged between the reed switch 2 and attached to the printed board 31.
This is to obtain the switching time when opening/closing the switches 3 and 24, and its effect will be described later.

When assembling the auxiliary contact device 4, the reed switch 2
3, 24, elastic contacts 33, 33, 34, 34,
The printed board 31 to which the magnetic pole piece 26 is attached is first fitted into the recess in the center of the base 10, and then the terminals 21, 21, 22, 22 of the auxiliary contacts are respectively fitted into predetermined positions on the base 10a, As a result, the contact portions 21a, 21a, 22a of each terminal,
22a and the contact portions 33a, 33a, 3 of the elastic contact piece
4a and 34a come into contact with each other elastically due to the elasticity of the elastic contact piece. Next, the movable rod 91 having a projection 91a and a hole 91b is inserted into the recess of the base 10a, and then a cover 10b having a window 10c through which the projection 91a passes is fixed to the base 10a to be assembled. The window 10f formed in the base 10a allows the movable rod 91 of the auxiliary contact device to be attached to the rear stage.
The protrusion 91a is formed to penetrate through the protrusion 91a.
The hole 10d formed in the auxiliary contact case 10 is a coupling screw through hole for attaching the auxiliary contact device 4 to the electromagnetic contactor body.

To attach this auxiliary contact device 4 to the electromagnetic contactor main body, use the same method as shown in FIG.
b to connect it to the movable contact support in the electromagnetic contactor main body 1, and the coupling screw is passed through the hole 10d of the auxiliary contact case 10 and screwed into the screw hole 1c of the electromagnetic contactor main body 1. When installing two stages of auxiliary contact devices 4 at the same time, insert the columnar protrusion 91a of the second auxiliary contact device 4 through the window 10c of the first auxiliary contact device 4 and the hole 91b of the movable rod 91.
It is only necessary to fit the auxiliary contact device 4 into the auxiliary contact device 4 and screw it using a longer length connecting screw than when there is only one auxiliary contact device 4.

Next, the operation of the auxiliary contact device 4 will be explained.

The contacts of the reed switches 23 and 24 close when the permanent magnet 25 approaches, and open when the permanent magnet 25 separates, and when the electromagnetic contactor body is in the return state, the movable rod 91 is at the solid line position shown in FIG. Since the permanent magnet 25 fixed to the movable rod 91 faces the reed switch 24, the reed switch 24 is closed and the reed switch 24 is opened. When the electromagnetic contactor body is turned on, the movable rod 91 is pulled down by the movable contactor in the electromagnetic contactor body to the position shown by the dotted line in FIG. 5, so that the permanent magnet 25 faces the reed switch 23. This closes the reed switch 23 and opens the reed switch 24. In this manner, in this embodiment, the auxiliary contact device 4 having one normally open contact (on the reed switch 23 side) and one normally closed contact (on the lead 24 side) operates.

By the way, in general, the auxiliary contact device 4, which consists of a normally open contact and a normally closed contact, has each contact at the same time during the switching operation of the electromagnetic contactor body (switching operation from the return state to the closing state and from the closing state to the return state). It is preferable not to close it. That is, during the switching operation from the return state to the closing state, the reed switch 24 must be opened first and then the lead 23 must be closed, and during the switching operation from the closing state to the return state, the reed switch 23 must be The reed switch 24 must be opened and then closed. The time (distance) from when one reed switch opens until the other reed switch closes is usually called switching time (switching distance). In order to obtain such a switching time, a magnetic pole piece 26 is installed between the reed switches 23 and 24 in the embodiment of the present invention. If the electromagnetic contactor body is now in the return state, the permanent magnet 25 is connected to the lead 24.
The reed switch 24 is closed and the reed switch 23 is opened. When the electromagnetic contactor main body is excited and the permanent magnet 25 approaches the magnetic pole piece 26 during its switching operation, most of the magnetic flux of the permanent magnet 25 flows through the magnetic pole piece 26, thereby opening the reed switch 24. At this time, a small amount of magnetic flux flows through the reed piece of the reed switch 23, but it does not close the contact and remains open. When the permanent magnet 25 separates from the magnetic pole piece 26 and approaches the reed switch 23, the magnetic flux of the permanent magnet 25 is transferred from the magnetic pole piece 26 to the reed switch 23.
Then the reed switch 23 is closed. Even during the switching operation in which the electromagnetic contactor main body is released and the closed state shifts to the returned state, the reed switch 23 is first opened and then the reed switch 24 is closed due to the action of the magnetic pole piece 26.

[Effect of idea]

The present invention described above has the following advantages. That is, since the opening and closing of the auxiliary contact device is performed by the contacts of the reed switch enclosed in the glass tube, and the connection between the reed switch and the terminal of the auxiliary contact is performed by elastic contact between the elastic contact piece and the terminal, the movable rod and There is no adverse effect from abrasion particles caused by friction with the auxiliary contact case or dust from the outside.

Since the reed switch and the terminal of the auxiliary contact are connected through the elastic contact piece, no mechanical stress is applied to the reed switch when connecting the wire to the terminal, and the life of the reed switch can be extended.

Assembling the auxiliary contact device is facilitated by attaching the reed switch and the elastic contact piece to the printed board.

Since the coil spring for maintaining the contact pressure between the movable contact and the fixed contact of the auxiliary contact device in the conventional device is not required, a larger number of auxiliary contact devices can be installed compared to the conventional device.
It has the advantage of Further, by arranging the magnetic pole piece at the intermediate position of the reed switch, there is an advantage that a stable switching time of the auxiliary contact can be obtained.

[Brief explanation of the drawing]

Figures 1 and 2 are a side cross-sectional view of a conventional auxiliary contact device and an assembled exploded view of the electromagnetic contactor body and auxiliary contact device, respectively, and Figure 3 is a diagram showing the electromagnetic contactor body and auxiliary contact device of a different conventional device. FIGS. 4 and 5 are a side sectional view and a side sectional view of an auxiliary contact device showing one embodiment of the present invention, respectively.
The A-A sectional view, FIG. 6A, and FIG. 6B are a front view and side view of the printed board, and FIG.
7B are a side view and a front view of the elastic contact piece, respectively. 1: Magnetic contactor body, 4: Auxiliary contact device, 1
0: Auxiliary contact case, 21, 22: Auxiliary contact terminal, 23, 24: Reed switch, 25: Permanent magnet, 26: Magnetic pole piece, 31: Printed board, 33, 3
4: Elastic contact piece, 91: Movable rod.

Claims (1)

[Scope of Claim for Utility Model Registration] 1. An auxiliary contact case attached to the electromagnetic contactor body, a movable member housed within the auxiliary contact case, connected to the movable contact support of the electromagnetic contactor body, and to which a permanent magnet is fixed. In an auxiliary contact device for an electromagnetic contactor, the reed switch is connected to a rod and a terminal of at least two sets of auxiliary contacts fixed to the auxiliary contact case, and operates in accordance with approach/separation of the permanent magnet. is attached to a printed board, an elastic contact piece for connecting the reed switch and the terminal of the auxiliary contact is attached to the printed board, and the printed board is installed in an auxiliary contact case. . 2. Utility Model Registration Claim 1. The auxiliary contact device for an electromagnetic contactor, wherein the printed board is fitted into a recess formed in the auxiliary contact case. 3 Utility Model Registration Scope of Claim 1. The auxiliary contact device for an electromagnetic contactor, characterized in that a magnetic piece is attached between each reed switch of the printed board in the device according to claim 1. 4. In the device described in claim 1 of the utility model registration claim, the elastic contact piece is U-shaped and has a spherical protrusion formed at one end that contacts the terminal of the auxiliary contact, and the other end is divided into a plurality of legs and has an appropriate shape. An auxiliary contact device for an electromagnetic contactor, characterized in that each leg is bent and raised and attached to a printed board.