JP2013008621A - Contactor and electromagnetic switch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect open/close of a contact part in a non-contact manner.SOLUTION: A detection part 3 includes a permanent magnet 31 attached to the bottom of a movable iron core 23 and a lead switch 30 disposed below a cap 24. When the contact part 1 is open, since the movable iron core 23 is positioned under the bottom of the cap 24, the lead switch 30 is turned ON due to magnetic force of the permanent magnet 31. When the contact part 1 is close, however, since the movable iron core 23 is positioned above an opening of the cap 24, the magnetic force of the permanent magnet 31 hardly affects on the movable iron core 23; thus the lead switch 30 is turned OFF. Accordingly, the open/close of the contact part 1 is detected based on the open/close of the lead switch 30 in a non-contact manner.

Description

  The present invention relates to a contact device and an electromagnetic switch using the contact device.

  There exist some which are described in patent document 1 as a conventional contact device and an electromagnetic switch. In this conventional example, a contact portion (contact device) sealed inside a sealed container, an electromagnet device that opens and closes the contact portion in response to energization of the coil, and a driving force of the electromagnet device is transmitted to the contact portion. The transmission member is housed in the housing. The transmission member is coupled to a movable shaft fixed to the movable iron core of the electromagnet device, and transmits a magnetic force acting on the movable iron core to the movable shaft to open and close the contact portion.

  In addition, this conventional example includes an auxiliary contact (microswitch), and when the pressing portion provided on the transmission member presses the drive lever, the auxiliary contact opens and closes in conjunction with the contact portion (the microswitch is turned on / off). By turning it off, it is possible to determine the open / closed state of the contact portion.

JP 2000-276961 A (see paragraphs 0002 to 0009 and FIGS. 10 and 11)

  However, in the above conventional example, the contact type is adopted as a method for detecting the switching state of the contact portion, so that the contact device or the electromagnetic switch reaches the end of its useful life due to the influence or deterioration of the auxiliary contact. There is a high possibility that the open / closed state of the part becomes undetectable.

  The present invention has been made in view of the above problems, and an object of the present invention is to make it possible to detect the open / closed state of a contact portion in a non-contact manner.

  The contact device of the present invention includes a contact portion having a fixed contact and a movable contact, opening / closing means for opening / closing the contact portion by displacing the movable contact, a container for accommodating at least the contact portion therein, and the contact Detecting means for detecting an open / closed state of the part, wherein the open / close means includes a displacement body for displacing the movable contact, and the detection means includes a permanent magnet that is integrally displaced with the displacement body, and the container And a magnetic detection unit arranged outside.

  In this contact device, it is preferable that the detection means has a protrusion protruding in a direction away from the contact portion along a displacement direction of the displacement body, and the permanent magnet is attached to the protrusion.

  In the contact device, it is preferable that the magnetic detection unit includes a reed switch.

  In this contact device, it is preferable that the magnetic detection unit is composed of a Hall element.

  In this contact device, it is preferable that the detection means has a second permanent magnet disposed in the vicinity of the Hall element.

  The contact device of the present invention includes a contact portion having a fixed contact and a movable contact, opening / closing means for opening / closing the contact portion by displacing the movable contact, a container for accommodating at least the contact portion therein, and the contact Detecting means for detecting an open / closed state of the part, the open / close means has a displacement body made of a magnetic material for displacing the movable contact, and the detection means includes a Hall element arranged outside the container; And a permanent magnet disposed in the vicinity of the Hall element.

  The electromagnetic switch according to the present invention includes any one of the contact devices and an electromagnet that displaces the displacement body by electromagnetic force.

  The contact device and the electromagnetic switch according to the present invention have an effect that the open / close state of the contact portion can be detected in a non-contact manner.

(a), (b) is sectional drawing which abbreviate | omitted partially showing Embodiment 1. FIG. (a)-(c) is sectional drawing which abbreviate | omitted partially showing Embodiment 2. FIG. FIG. 6 is a partially omitted cross-sectional view showing a third embodiment.

(Embodiment 1)
As shown in FIG. 1A, the electromagnetic switch A1 of this embodiment includes a contact portion 1, a drive portion 2, a detection portion 3, and the like. The contact portion 1 includes two fixed contacts 10 and a movable contact (movable element) 11 that contacts and separates from the fixed contact 10. That is, when the two fixed contacts 10 and the movable contact 11 are in contact with each other, the contact portion 1 is closed and the fixed contact 10 is electrically connected, and the two fixed contacts 10 and the movable contact 11 are not in contact with each other. The contact portion 1 is opened and the fixed contact 10 is not conductive. In the following description, the vertical and horizontal directions are defined in FIG.

  The fixed contact 10 is provided at the tip (lower end) of a cylindrical fixed terminal 10A. The movable contact 11 is formed in a rectangular flat plate shape made of copper or a copper alloy, and is supported on the movable shaft 21 at the center in the longitudinal direction (left-right direction). The fixed contact 10 and the movable contact 11 are housed in a ceramic sealing container 12 formed in a box shape with an open bottom surface, and a pair of fixed terminals 10A penetrates the bottom wall of the sealing container 12. is doing.

  The drive unit 2 includes an exciting coil 20, a movable shaft 21, a fixed iron core 22, a movable iron core 23, a cap 24, yokes 25 and 26, and the like. The cap 24 is formed of a nonmagnetic material in a bottomed cylindrical shape, and the movable iron core 23 is accommodated on the bottom (lower) side of the cap 24, and the fixed iron core 22 is accommodated and fixed on the opening (upper) side. The movable shaft 21 movably passes through the fixed iron core 22, and a movable iron core 23 is fixed to the lower end portion. Although not shown, a return spring is provided between the fixed iron core 22 and the movable iron core 23 to elastically urge the movable iron core 23 in a direction away from the fixed iron core 22 (downward). A contact pressure spring (not shown) that elastically biases the movable contact 11 in a direction (upward) toward the fixed contact 10 is disposed between the fixed iron core 22 and the movable contact 11. A coil bobbin (not shown) made of an insulating material is provided outside the cap 24, and the exciting coil 20 is wound around the coil bobbin. The yokes 25 and 26 are disposed outside the exciting coil 20, and a magnetic circuit is formed by the exciting coil 20 and the yokes 25 and 26. One yoke 26 is formed in a flat plate shape and is disposed between the exciting coil 20 and the sealing container 12.

  Thus, in a state where no exciting current flows through the exciting coil 20, the movable shaft 21 and the movable contact 11 are also displaced downward when the movable core 23 elastically biased by the return spring is displaced (moved) downward. . As a result, the movable contact 11 is separated from the fixed contact 10 and the contact portion 1 is opened. On the other hand, when an exciting current flows through the exciting coil 20, the movable iron core 23 is displaced in the direction approaching the fixed iron core 22 (upward) by the electromagnetic force acting between the fixed iron core 22 and the movable iron core 23. The movable contact 11 is also displaced upward. As a result, the movable contact 11 contacts the fixed contact 10 and the contact portion 1 is closed. That is, in this embodiment, a contact device is constituted by the contact portion 1, the movable shaft 21, the sealing container 12, the cap 24, etc., and an electromagnet is constituted by the exciting coil 20 and the fixed iron core 22, and the electromagnetic force of this electromagnet. As a result, the movable iron core 23 and the movable shaft 21 are displaced in the vertical direction.

  The detection unit 3 detects the open / close state of the contact unit 1, and includes a permanent magnet 31 attached to the lower surface of the movable iron core 23 and a reed switch 30 disposed below the cap 24. That is, when the contact portion 1 is open, the reed switch 30 is turned on by the magnetic force of the permanent magnet 31 because the movable iron core 23 is located on the bottom (lower) side of the cap 24. However, when the contact portion 1 is closed, the movable iron core 23 is positioned on the opening (upper) side of the cap 24, so that the magnetic force of the permanent magnet 31 becomes difficult to turn off the reed switch 30.

  As described above, in the present embodiment, it is possible to detect the open / close state of the contact portion 1 in a non-contact manner based on the on / off of the reed switch 30 that is a magnetic detection portion. As a result, the contact device and the electromagnetic switch A1 The possibility that the detection unit 3 becomes undetectable before reaching the useful life can be reduced.

  However, in order to reduce the influence of the electromagnetic force of the electromagnet on the reed switch 30, as shown in FIG. 1 (b), the protrusion protruding in the direction away from the contact portion 1 (downward) along the displacement direction of the movable core 23 32 may be provided, and the permanent magnet 31 may be attached to the tip (lower end) of the protrusion 32. In this case, it is desirable that the reed switch 30 be disposed on the side surface of the cap 24.

(Embodiment 2)
Since the basic configuration of the contact device and the electromagnetic switch A2 of the present embodiment is the same as that of the first embodiment, the same reference numerals are given to the same components as those of the first embodiment, and illustration and description thereof are omitted as appropriate. .

  The detection unit 3 in the present embodiment has a Hall element 33 arranged below the cap 24 as shown in FIG. That is, since the output of the Hall element 33 changes according to the magnetic strength (magnetic flux density) of the permanent magnet 31 attached to the lower end of the movable core 23, the position of the permanent magnet 31 is based on the output of the Hall element 33. That is, the open / closed state of the contact portion 1 can be determined.

  However, in order to reduce the influence of the electromagnetic force of the electromagnet, a permanent magnet 31 is attached to the tip (lower end) of the protrusion 32 protruding from the lower end of the movable iron core 23 as shown in FIG. The Hall element 33 may be disposed in the front. Alternatively, as shown in FIG. 2C, the second permanent magnet 34 may be disposed in the vicinity (lower surface) of the Hall element 33. In this case, the magnetic strength (magnetic flux density) of the second permanent magnet 34 detected by the Hall element 33 changes according to the distance between the permanent magnet 31 and the Hall element 33, and as a result, the output of the Hall element 33. Therefore, the open / closed state of the contact portion 1 can be detected in a non-contact manner based on the output of the Hall element 33. In addition, this configuration has an advantage that the detection unit 3 is hardly affected by the electromagnetic force of the electromagnet.

(Embodiment 3)
Since the basic configuration of the contact device and the electromagnetic switch A3 of this embodiment is the same as that of the second embodiment, the same components as those of the second embodiment are denoted by the same reference numerals, and illustration and description thereof are omitted as appropriate. .

  As shown in FIG. 3, the detection unit 3 in the present embodiment has no permanent magnet attached to the movable iron core 23, and the permanent magnet 34 is disposed only in the vicinity (lower surface) of the Hall element 33.

  That is, the magnetic strength (magnetic flux density) of the permanent magnet 34 detected by the Hall element 33 changes according to the distance from the movable core 23, and as a result, the output of the Hall element 33 also changes. Based on the output of 33, the open / closed state of the contact portion 1 can be detected without contact. In addition, this configuration has an advantage that the detection unit 3 is hardly affected by the electromagnetic force of the electromagnet.

A1 Electromagnetic switch 1 Contact part (contact device)
2 Drive unit (opening / closing means)
3 Detection part (detection means)
10 Fixed contact
11 Moving contact
12 Sealed container (container)
20 Excitation coil (electromagnet)
21 Movable shaft (contact device)
22 Fixed iron core (electromagnet)
23 Movable iron core (displacement body)
30 Reed switch (magnetic detector)
31 Permanent magnet

Claims (7)

  A contact portion having a fixed contact and a movable contact; an opening / closing means for opening and closing the contact portion by displacing the movable contact; a container for accommodating at least the contact portion; and an open / closed state of the contact portion. Detecting means, and the opening / closing means has a displacement body for displacing the movable contact, and the detection means is a permanent magnet that is integrally displaced with the displacement body, and magnetic detection arranged outside the container. And a contact device.   2. The contact according to claim 1, wherein the detection unit has a protrusion protruding in a direction away from the contact portion along a displacement direction of the displacement body, and the permanent magnet is attached to the protrusion. apparatus.   The contact device according to claim 1, wherein the magnetic detection unit includes a reed switch.   The contact device according to claim 1, wherein the magnetic detection unit includes a Hall element.   The contact device according to claim 4, wherein the detection unit includes a second permanent magnet disposed in the vicinity of the Hall element.   A contact portion having a fixed contact and a movable contact; an opening / closing means for opening and closing the contact portion by displacing the movable contact; a container for accommodating at least the contact portion; and an open / closed state of the contact portion. Detecting means, wherein the opening / closing means has a displacement body made of a magnetic material for displacing the movable contact, and the detecting means is arranged in the vicinity of the Hall element and the Hall element arranged outside the container. A contact device comprising a permanent magnet.   An electromagnetic switch comprising: the contact device according to claim 1; and an electromagnet that displaces the displacement body by electromagnetic force.

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