JP4877309B2 - Electromagnetic relay - Google Patents

Description

  The present invention relates to an electromagnetic relay.

  Conventionally, this type of electromagnetic relay includes an iron block around which a coil is wound and an electromagnetic block having a yoke that forms a magnetic circuit with the iron core, and a fixed contact and a fixed contact according to whether the coil is energized. A contact block having a movable contact configured to be freely contactable and separable; and an approximately rectangular box-shaped case that houses the electromagnet block and the contact block therein, and is connected to the coil of the electromagnet block from the bottom surface of the case A coil terminal, a fixed contact terminal of a contact block, a fixed contact terminal connected to the movable contact, and a movable contact terminal are provided. In the electromagnetic relay, the air around the coil warmed by the heat generated by the coil reaches the contact portion composed of the movable contact and the fixed contact having a temperature lower than that of the other portion in the case. When condensation occurs and the temperature of the contact point further decreases, there is a risk that condensation will freeze and conduction problems may occur.

Therefore, a metal plate with high thermal conductivity is penetrated to the bottom or side surface of the case, and condensation is generated on the case inner surface side of the metal plate, thereby reducing the amount of moisture contained in the air in the case, and Some attempt to prevent condensation and icing (for example, see Patent Documents 1 and 2).
JP 2003-031095 A Japanese Unexamined Patent Publication No. 64-19904

  However, in general, an electromagnetic relay is such that each terminal is inserted into a socket arranged in a panel such as a control panel, so the bottom surface of the case is in contact with the socket and close to the inner surface of the panel. The air near the bottom of the case is likely to be trapped. Therefore, the heat dissipation performance of the metal plate provided on the bottom surface of the case is lowered, and the temperature of the metal plate is difficult to decrease. Therefore, no condensation occurs on the metal plate, and there is a possibility that condensation occurs at the contact portion having a low temperature in the case.

  In general, sockets are arranged side by side in the board, and electromagnetic relays are arranged in parallel in the board by inserting each terminal into the socket. Accordingly, the side surfaces of the case and the other devices arranged in the panel other than the electromagnetic relay are close to the side surface of the case, so that air in the vicinity of the side surface of the case is easily trapped. For this reason, the heat dissipation performance of the metal plate is lowered, and the temperature of the metal plate is hardly lowered. Therefore, no condensation occurs on the metal plate, and there is a possibility that condensation occurs at the contact portion having a low temperature in the case.

  Thus, in the conventional electromagnetic relay provided with a metal plate with high thermal conductivity on the bottom or side of the case, the installation state with the terminal inserted into the socket is not considered, so the heat dissipation performance of the metal plate is If the temperature of the metal plate does not fall below the temperature of the contact part and condensation occurs at the contact part, and the temperature of the contact part further decreases, there is a risk that conduction failure may occur due to icing of the condensation. is there.

  Moreover, since the metal plate which is another part is penetrated in the case, there also existed a problem that a structure became complicated.

  The present invention has been made in view of the above reasons, and its purpose is that the structure is simple and condensation and icing occur at the contact portion in consideration of the installation state with the terminal inserted into the socket. It is providing the electromagnetic relay which can suppress this and can prevent the conduction | electrical_connection defect of a contact part.

According to the first aspect of the present invention, there is provided an electromagnet block including an iron core around which a coil is wound, a yoke that forms a magnetic circuit together with the iron core, a fixed contact, and the fixed according to whether the coil is energized or not. A contact block having a movable contact configured to be freely contactable with and disengaged from the contact; and a case housing the electromagnet block and the contact block therein; and connecting to the coil of the electromagnet block from one surface of the case Coil terminal, the fixed contact of the contact block, the fixed contact terminal connected to the movable contact, and the movable contact terminal project, and on the other surface facing the one surface, the movable contact and the fixed contact in a position facing the contact portion made of, such other surfaces thin walled portion thicker than other portions is provided in, directed to the outside of the casing in the thin portion Surface is characterized by a flat.

  According to the present invention, the installation state with the terminal inserted into the socket is taken into consideration, and even when a plurality of the terminals are arranged in parallel, there is no air around the other surface (top surface) of the case provided with the thin wall portion. Since there is no obstruction that obstructs the flow, the heat dissipation performance of the thin part can be maintained, and the temperature of the thin part is lower than the temperature of the contact part, and the moisture contained in the air in the case heated by the coil is in the thin part. By condensing on the inner surface of the case, the amount of moisture contained in the air in the case is reduced, and the occurrence of condensation and icing at the contact portion is suppressed, and conduction failure of the contact portion can be prevented.

In addition, the thin-walled portion is provided by forming the case so that the thickness of a predetermined location is thinner than the thickness of other portions when the case is formed. Structure. Furthermore, on the top surface of the case, a thin part is provided at a position that is the shortest distance from the contact part, so that moisture contained in the air around the contact part is condensed in the thin part, and condensation and icing are formed on the contact part. Generation | occurrence | production is further suppressed and the prevention effect of the conduction | electrical_connection defect of a contact part can be heightened.

  As described above, in the present invention, in consideration of the installation state with the structure being simple and the terminal being inserted into the socket, it is possible to suppress the occurrence of dew condensation and icing on the contact portion, and to conduct the contact portion. This has the effect of preventing problems.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment)
As shown in FIGS. 1 to 3, the electromagnetic relay in this embodiment houses an electromagnet block 2, an armature 3, and a contact block 4 inside a case 1 formed in a box shape from an insulating material such as resin. is doing. In the following, the direction perpendicular to the up / down / left / right direction is defined as the front / rear direction with reference to the up / down / left / right direction in FIG.

  The electromagnet block 2 includes a hollow cylindrical coil bobbin 22 around which the coil 21 is wound, an iron core 23 inserted through the inner diameter portion 22 a of the coil bobbin 22, and a yoke 24 that forms a magnetic circuit together with the iron core 23.

  The coil bobbin 22 is made of an insulating material such as a resin, and the flange portions 22b and 22c are formed at both upper and lower ends in the axial direction, and the coil 21 is wound between the flange portion 22b and the flange portion 22c.

  The iron core 23 is formed in a long cylindrical shape, and a flange portion 23a is formed at the lower end. The flange portion 23a is fitted into a circular recess 22d formed at the approximate center of the flange portion 22c of the coil bobbin 22.

  The yoke 24 is made of a magnetic material and is substantially L-shaped from one piece 24a and the other piece 24b extending downward from the right end of the one piece 24a. The one piece 24a is fitted into a recess 22e formed in the flange portion 22b of the coil bobbin 22, and an insertion hole 24c is formed. The upper end portion of the iron core 23 is inserted into the insertion hole 24c. The other piece 24 b is formed along the right end of the coil bobbin 22.

  The armature 3 is formed of a magnetic material into a long flat plate shape, and is disposed to face the flange portion 23 a of the iron core 23.

  The contact block 4 includes fixed contacts 41 and 46, a movable contact 43 configured to be able to come into and out of contact with the fixed contacts 41 and 46 according to whether the coil 21 is energized, and a movable contact plate on which the movable contact 43 is provided. 44, the fixed contacts 41 and 46 are connected to the fixed contact terminals 42 and 47, respectively, and the movable contact 43 is connected to the movable contact terminal 45 via the movable contact plate 44.

  The fixed contact terminal 42 includes a long flat plate-like terminal portion 42a that is long in the vertical direction and an extending portion 42b that extends leftward from the upper end of the terminal portion 42a, and is substantially L-shaped by a conductive material such as copper. The fixed contact 41 is provided in the vicinity of the tip of the extended portion 42b.

  The fixed contact terminal 47 is a long flat terminal portion made of a conductive material such as copper, and the fixed contact 46 is provided at a position facing the fixed contact 41 in the vertical direction.

  The movable contact plate 44 is formed in a substantially L shape with a conductive material such as copper, with a plate spring-like operating piece 44a that is long in the left-right direction and a fixed piece 44b that extends upward from the right end of the operating piece 44a. Has been. The armature 3 is fixed to the upper right side of the operating piece 44a, and a movable contact 43 is provided near the tip at a position facing the fixed contacts 41 and 46. In the electromagnetic relay of the present embodiment, the movable contact 43 contacts the fixed contact 46 when no current flows through the coil 21, and the movable contact 43 contacts the fixed contact 41 when current flows through the coil 21. A contact structure of a so-called c contact. The fixed piece 44b is provided between the other piece 24b of the yoke 24 and the movable contact terminal 45, and is fixed to the upper end side of the movable contact terminal 45 by caulking or the like.

  The movable contact terminal 45 is formed in a long plate shape that is long in the vertical direction by a conductive material such as copper.

  The case 1 includes a substantially rectangular flat base 11 and a substantially rectangular box-shaped cover 12 whose bottom surface is open and covers the base 11. The base 11 includes a terminal portion 42 a of a fixed contact terminal 42 and a terminal portion 42 a. Further, insertion holes (not shown) through which the movable contact terminal 45 and the pair of coil terminals 25 to which the tips of the coils 21 are respectively connected are inserted. The coil terminal 25 is formed in a long plate shape that is long in the vertical direction by a conductive material such as copper, and the tip of the coil 21 is wound around the upper end of the coil terminal 25 and connected by solder or the like.

  A concave portion is formed on the top surface 12a of the cover 12 facing the base 11 in the vertical direction on the upper surface at a position facing the contact portion 40 including the fixed contact 41 and the movable contact 43 in the vertical direction. Two thin portions 121 are juxtaposed in the front-rear direction. The thin portion 121 is formed so as to have the thinnest thickness in the top surface 12a of the case 1, and the upper surface is exposed in the outer space of the case 1 and the lower surface is exposed in the inner space of the case 1. Is provided. The thickness of the thin wall portion 121 is determined so that the upper surface is cooled by the outside air, and the thickness is determined so that the lower surface is cooler than the contact portion 40 in the case 1. The thickness is determined by the amount of heat generation and the size of the case 1. Further, since the thin portion 121 is formed at the same time when the cover 12 is formed with resin, it does not require a separate part such as a metal plate provided in a case of a conventional electromagnetic relay and has a simple structure. In the present embodiment, the thin portion 121 is the thinnest among the top surfaces 12 a of the case 1, but may be the thinnest among the surfaces constituting the case 1.

  In general, an electromagnetic relay is configured such that each terminal (a pair of coil terminals 25, a fixed contact terminal 42, and a movable contact terminal 45) is inserted into a socket provided in a panel such as a control panel (not shown). Is in contact with the socket and close to the inner surface of the board, and air near the bottom surface of the case 1 tends to be trapped. Furthermore, generally, since the sockets are arranged in parallel in the panel, the electromagnetic relays in which the terminal portions are inserted into the sockets are arranged in parallel, and the devices arranged on the sides of the case 1 or in the panel other than the electromagnetic relays. And the side surface of the case 1 are close to each other, and air near the side surface of the case 1 is also easily trapped.

  In the electromagnetic relay of the present embodiment having the above-described configuration, when the coil 21 is energized, the armature 23 is magnetized so that the armature 3 is attracted to the flange 23a of the iron core 23, and the armature is accordingly provided. 3, the distal end of the operating piece 44 a of the movable contact plate 44 connected to 3 is displaced upward, the movable contact 43 provided at the distal end contacts the fixed contact 41, and the space between the fixed contact terminal 42 and the movable contact terminal 45 is between Conduct.

  When the coil 21 is energized, the air in the vicinity of the coil 21 becomes hot due to the heat generated by the coil 21, and the hot air becomes a lower temperature part than the contact part 40 in the case 1 by touching the outside air. By reaching the thin portion 121, condensation occurs in the thin portion 121. As a result, the amount of moisture contained in the air in the case 1 can be reduced, and the occurrence of condensation on the contact portion 40 can be prevented. In addition, when the electromagnetic relay is installed in parallel with each terminal being inserted into a socket in the panel, the top surface 12a on which the thin portion 121 is provided is exposed upward, and the air flow is obstructed around the top surface 12a. Since there is no shield, the heat dissipation performance can be maintained, and the thin portion 121 is kept at a low temperature. Furthermore, since the thin portion 121 is formed at a position that is the shortest distance from the contact portion 40 on the top surface 12a of the cover 12, more moisture contained in the air around the contact portion 40 is condensed on the thin portion 121. As a result, the amount of moisture contained in the air in the vicinity of the contact portion 40 is reduced, and the occurrence of condensation on the contact portion 40 can be further suppressed.

  As described above, in the electromagnetic relay according to the present embodiment, the location where the thin portion 121 is formed is determined in consideration of the installation state in which the terminal is inserted into the socket. It is suppressed effectively and the conduction | electrical_connection defect of a contact part can be prevented. In addition, since a separate part is not required to provide the thin portion 121, a simple structure can be achieved.

The schematic of the AA cross section of the electromagnetic relay in embodiment of this invention is shown. The top view of the electromagnetic relay in the same as the above is shown. (A), (b) shows the cross-sectional schematic of the electromagnetic relay in the same as the above, (a) shows a BB cross section, (b) shows a CC cross section.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Case 2 Electromagnetic block 3 Armature 4 Contact block 21 Coil 23 Iron core 24 Relay 25 Coil terminal 41 Fixed contact 42 Fixed contact terminal 43 Movable contact 45 Movable contact terminal 46 Fixed contact 47 Fixed contact terminal 121 Thin part

Claims (1)

An electromagnetic block comprising an iron core around which a coil is wound, and a yoke that forms a magnetic circuit with the iron core;
A contact block comprising a fixed contact and a movable contact configured to be able to contact and separate from the fixed contact in accordance with on / off of energization of the coil;
A case for accommodating the electromagnet block and the contact block therein;
From one surface of the case, a coil terminal connected to the coil of the electromagnet block, the fixed contact of the contact block, a fixed contact terminal connected to the movable contact, and a movable contact terminal protrude from the one surface. In the opposite other surface, a position where the movable contact and the fixed contact are opposed to each other is provided with a thin portion that is thinner than other portions in the other surface . The electromagnetic relay according to claim 1 , wherein a surface directed to the outside of the case is flat .

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