JP7468277B2 - Electromagnetic Relay - Google Patents

Description

The present invention relates to an electromagnetic relay.

In a hinge-type electromagnetic relay equipped with a hinge spring, an electromagnetic relay is known in which the hinge spring is fixed to a spool to ensure space for the coil (see Patent Document 1). A movable iron piece is connected to the hinge spring.

Japanese Patent Application Laid-Open No. 10-125200

When the hinge spring is fixed to peripheral parts made of materials other than magnetic materials, such as a spool or base, as in the electromagnetic relay disclosed in Patent Document 1, it is difficult to position the hinge spring with precision because it is subject to dimensional changes due to the environment and assembly tolerances. As a result, it is difficult to position the movable iron piece connected to the hinge spring with precision, and it is difficult to accurately position the movable iron piece relative to the attraction surface to which the movable iron piece is attracted.

The objective of the present invention is to improve the positioning accuracy of the movable iron piece connected to the hinge spring in an electromagnetic relay.

An electromagnetic relay according to one aspect of the present invention includes a movable iron piece, a drive unit, and a hinge spring. The drive unit includes a coil and a fixed iron core arranged inside the coil. The drive unit moves the movable iron piece by electromagnetic force. The hinge spring includes a connecting unit to which the movable iron piece is connected. The hinge spring is arranged in contact with the fixed iron core and is positionally restricted by the fixed iron core. The hinge spring biases the movable iron piece in a direction away from the fixed iron core.

In this electromagnetic relay, the position of the hinge spring is restricted by a fixed iron core, which is a magnetic material. Therefore, compared to when the hinge spring is fixed to a spool or base, it is less susceptible to environmental dimensional changes and assembly tolerances, and the hinge spring can be positioned with high precision. As a result, it is possible to improve the positioning precision of the movable iron piece connected to the hinge spring. This makes it possible to improve the positioning precision of the movable iron piece relative to the attraction surface to which the movable iron piece is attracted.

The hinge spring may further include a fitting portion that fits onto the outer peripheral surface of the fixed iron core. In this case, the position of the hinge spring can be regulated by the fixed iron core with a simple structure.

The drive unit may further include a spool. The spool may include a bobbin having an insertion hole into which the fixed core is inserted and around which the coil is wound. The fixed core may include a main body portion inserted into the insertion hole and a flange portion formed at an end of the main body portion and having a diameter larger than the diameter of the insertion hole. The fitting portion of the hinge spring may be sandwiched between the bobbin of the spool and the flange portion of the fixed core. In this case, the position of the hinge spring can also be regulated by the spool and the fixed core.

The drive unit may further include a spool. The spool may include a bobbin having a hole into which the fixed core is inserted and around which the coil is wound. The fixed core may include a main body portion inserted into the insertion hole and an engaging portion formed on the outer circumferential surface of the main body portion. The hinge spring may further include an engaged portion disposed inside the insertion hole and engaging with the engaging portion. In this case, the fixed core can regulate the position of the hinge spring and can prevent the hinge spring from slipping out of the bobbin insertion hole.

The engaged portion of the hinge spring may be formed to surround the outer circumferential surface of the main body of the fixed core. In this case, the hinge spring can be regulated in position by the fixed core and the hinge spring can be prevented from slipping out of the bobbin insertion hole.

The engaged portion of the hinge spring may be sandwiched between the bobbin of the spool and the main body of the fixed core. In this case, the position of the hinge spring can also be regulated by the spool and the fixed core.

The connection portion of the hinge spring may include an insertion hole into which the movable iron piece is inserted. In this case, the movable iron piece can be connected to the hinge spring with a simple structure.

The connecting portion of the hinge spring may include a connecting hole through which a portion of the movable iron piece passes. The movable iron piece may include a hook portion that is hooked onto the connecting hole. In this case, the movable iron piece can be connected to the hinge spring with a simple structure.

Either the connecting portion or the movable iron piece of the hinge spring may include a press-fit protrusion. The other of the connecting portion or the movable iron piece of the hinge spring may include a recess into which the press-fit protrusion is pressed. In this case, the movable iron piece can be connected to the hinge spring with a simple structure.

The movable iron piece may rotate around the fixed iron core or the connecting part as a fulcrum when moved by electromagnetic force. In this case, it is possible to form a thin coil, which allows the drive unit to be made more compact.

The drive unit may further include a yoke that is connected to the fixed core and surrounds at least a portion of the coil. The yoke may include an attraction surface that attracts the movable iron piece by electromagnetic force. In this case, it is possible to improve the positioning accuracy of the movable iron piece relative to the attraction surface of the yoke.

The present invention makes it possible to improve the positioning accuracy of the movable iron piece connected to the hinge spring in an electromagnetic relay.

2 is a schematic diagram showing the inside of an electromagnetic relay as viewed from the front. FIG. 2 is a schematic diagram showing the inside of an electromagnetic relay as viewed from the front. FIG. FIG. 2 is a schematic diagram of the drive unit and its periphery as viewed from the front. 13 is a schematic diagram of a fitting portion of a hinge spring as viewed from above. FIG. 4 is a cross-sectional view taken along line VV in FIG. 3. 13 is a schematic diagram of the periphery of a drive unit according to a modified example, as viewed from the front. FIG. 13 is a schematic diagram of the periphery of a drive unit according to a modified example, as viewed from the front. FIG. 13 is a schematic diagram of the periphery of a drive unit according to a modified example, as viewed from the front. FIG. 13 is a schematic diagram of the periphery of a drive unit according to a modified example, as viewed from the front. FIG. FIG. 13 is a schematic cross-sectional view of the periphery of a drive unit according to a modified example. FIG. 13 is a schematic cross-sectional view of the periphery of a drive unit according to a modified example.

Below, an embodiment of an electromagnetic relay according to one aspect of the present invention will be described with reference to the drawings. When referring to the drawings, for ease of understanding, the upper side in FIG. 1 will be referred to as "upper", the lower side as "lower", the left side as "left", the right side as "right", the front side of the page as "front", and the back side of the page as "rear". FIG. 1 is a schematic diagram of the inside of an electromagnetic relay 100 as seen from the front.

The electromagnetic relay 100 is a so-called hinge-type electromagnetic relay. The electromagnetic relay 100 includes a case 2, a contact device 3, a drive unit 4, a hinge spring 5, and a movable iron piece 6. The case 2 is generally box-shaped and is made of an insulating material such as resin. The case 2 houses the contact device 3, the drive unit 4, the hinge spring 5, and the movable iron piece 6.

The contact device 3 includes a fixed terminal 8 and a movable contact piece 9. The fixed terminal 8 and the movable contact piece 9 are plate-shaped terminals made of a conductive material such as copper. The fixed terminal 8 and the movable contact piece 9 are supported by the case 2. In this embodiment, the fixed terminal 8 and the movable contact piece 9 extend in the left-right direction.

The fixed terminal 8 includes a fixed contact 8a and an external connection portion 8b. The fixed contact 8a is disposed within the case 2. The fixed contact 8a may be separate from the fixed terminal 8 or may be integrated with the fixed terminal 8. The external connection portion 8b protrudes to the outside from the case 2 and is electrically connected to an external device (not shown).

The movable contact piece 9 is composed of an elastically deformable leaf spring. The movable contact piece 9 includes a movable contact 9a. The movable contact 9a is disposed opposite the fixed contact 8a and can come into contact with the fixed contact 8a. The movable contact 9a may be separate from the movable contact piece 9 or may be integral with the movable contact piece 9.

The drive unit 4 operates the movable iron piece 6 by electromagnetic force. The drive unit 4 is supported by the case 2. In detail, the drive unit 4 rotates the movable iron piece 6 to move the movable contact piece 9 between the open position shown in FIG. 1 and the contact position shown in FIG. 2. In the open position, the movable contact 9a and the fixed contact 8a are separated from each other. In the contact position, the movable contact 9a and the fixed contact 8a are in contact with each other.

Figure 3 is a schematic diagram of the driving unit 4 and its periphery seen from the front. The driving unit 4 includes a spool 41, a coil 42, a fixed core 43, and a yoke 44. The spool 41 includes a bobbin 41a. The bobbin 41a is cylindrical and extends in the vertical direction. The coil 42 is wound around the outer periphery of the bobbin 41a. The bobbin 41a has an insertion hole 41b into which the fixed core 43 is inserted. The insertion hole 41b is formed to penetrate the inside of the bobbin 41a in the vertical direction.

The coil 42 is wound around the bobbin 41a. When a voltage is applied to the coil 42 and it is excited, it generates an electromagnetic force that moves the movable iron piece 6.

The fixed core 43 is disposed inside the coil 42. The lower end of the fixed core 43 is connected to the yoke 44. The fixed core 43 is fixed to the yoke 44 by crimping. The fixed core 43 is fixed to the case 2.

The fixed core 43 includes a body portion 43a and a flange portion 43b. The body portion 43a is inserted into the insertion hole 41b of the bobbin 41a. The cross-sectional shape of the body portion 43a is approximately circular. The flange portion 43b is formed at the end (here, the upper end) of the body portion 43a. The flange portion 43b is formed with a diameter larger than the diameter of the insertion hole 41b. Therefore, the flange portion 43b is disposed outside the insertion hole 41b. The cross-sectional shape of the body portion 43a may be approximately rectangular.

The yoke 44 is connected to the fixed core 43. The yoke 44 surrounds at least a portion of the coil 42. The yoke 44 is fixed to the case 2 via the fixed core 43. The yoke 44 has an L-shaped bent shape. In detail, the yoke 44 includes a connecting portion 44a, a standing portion 44b, and an adsorption surface 44c. The connecting portion 44a is arranged in contact with the lower portion of the case 2. The fixed core 43 is fixed to the connecting portion 44a. The standing portion 44b extends upward from one end of the connecting portion 44a. The standing portion 44b is arranged on the outer periphery side of the bobbin 41a and covers a portion of the coil 42. The adsorption surface 44c is formed at the upper end of the standing portion 44b. In this embodiment, the adsorption surface 44c is formed by the upper end surface of the standing portion 44b. The adsorption surface 44c is arranged facing the movable iron piece 6. The adsorption surface 44c is located below the movable iron piece 6 and is spaced apart from the movable iron piece 6 in the vertical direction.

The hinge spring 5 biases the movable iron piece 6 in a direction away from the fixed iron core 43. The hinge spring 5 biases the movable iron piece 6 in a direction away from the adsorption surface 44c. The hinge spring 5 is arranged in contact with the fixed iron core 43. The position of the hinge spring 5 is restricted by the fixed iron core 43. The hinge spring 5 has an L-shaped bent shape.

The hinge spring 5 includes a fitting portion 51 and a connecting portion 52. The fitting portion 51 fits into the outer peripheral surface of the fixed core 43. FIG. 4 is a schematic diagram of the fitting portion 51 seen from above. As shown in FIG. 4, the fitting portion 51 in this embodiment has a shape corresponding to the outer peripheral surface of the main body portion 43a of the fixed core 43, and fits into the outer peripheral surface of the main body portion 43a. The fitting portion 51 has an opening for fitting the fitting portion 51 into the main body portion 43a. By fitting the fitting portion 51 into the main body portion 43a, the position of the hinge spring 5 is restricted to the fixed core 43. The fitting portion 51 is disposed between the bobbin 41a of the spool 41 and the flange portion 43b of the fixed core 43. The fitting portion 51 is sandwiched between the bobbin 41a and the flange portion 43b, and is also restricted in position by the spool 41 and the fixed core 43. The position of the hinge spring 5 may be restricted only by the fixed core 43. For example, an engagement portion such as a groove with which the fitting portion 51 engages may be provided on the outer circumferential surface of the main body portion 43a.

The connecting portion 52 extends upward from the fitting portion 51. The connecting portion 52 is positioned so as not to overlap with the flange portion 43b in the vertical direction. The connecting portion 52 is the portion where the movable iron piece 6 is connected to the hinge spring 5.

Figure 5 is a cross-sectional view of the hinge spring 5 and the movable iron piece 6 taken along line V-V in Figure 3. The connecting part 52 includes a connecting hole 52a through which a part of the movable iron piece 6 passes. The connecting hole 52a is formed penetrating the connecting part 52 in the left-right direction. The connecting hole 52a includes a press-fit protrusion 52b for lightly press-fitting the movable iron piece 6 into the connecting hole 52a.

One end of the movable iron piece 6 is connected to the hinge spring 5. The movable iron piece 6 includes a protrusion 6a that passes through the connecting hole 52a. As shown in FIG. 5, the protrusion 6a has a recess 6b into which the press-fit protrusion 52b is press-fitted. The tip of the protrusion 6a is exposed from the connecting hole 52a. As shown in FIG. 1 and FIG. 2, the other end of the movable iron piece 6 is connected to a pressing member 21 that presses the movable contact piece 9. The pressing member 21 is made of an insulating material such as resin, and insulates the movable iron piece 6 from the movable contact piece 9.

When the movable iron piece 6 moves due to electromagnetic force, it rotates around the fixed iron core 43 as a fulcrum. In detail, the movable iron piece 6 is in contact with the upper end corner 43c of the flange 43b of the fixed iron core 43 close to the connecting portion 52. When the movable iron piece 6 is attracted to the attraction surface 44c by electromagnetic force, it rotates around the upper end corner 43c as a fulcrum in a direction approaching the attraction surface 44c. Note that the movable iron piece 6 may rotate around the connecting portion 52 as a fulcrum in a direction approaching the attraction surface 44c, and may not be in contact with the fixed iron core 43.

Next, the operation of the electromagnetic relay 100 will be described. FIG. 1 shows a state in which no voltage is applied to the coil 42. When no voltage is applied to the coil 42, the movable contact piece 9 is in the open position. That is, the elastic force of the hinge spring 5 and the movable contact piece 9 prevents the movable contact piece 9 from moving to the contact position by the pressing member 21. When a voltage is applied to the coil 42 and the coil 42 is excited, the movable iron piece 6 is attracted to the adsorption surface 44c by the electromagnetic force. As a result, the movable iron piece 6 rotates in a direction approaching the adsorption surface 44c with the upper end corner 43c as a fulcrum against the elastic force of the hinge spring 5 and the movable contact piece 9. As a result, the movable contact piece 9 is pressed by the pressing member 21 and moves to the contact position, so that the movable contact 9a contacts the fixed contact 8a. When the application of the voltage to the coil 42 is stopped, the elastic force of the hinge spring 5 and the movable contact piece 9 causes the movable iron piece 6 to rotate in a direction away from the adsorption surface 44c. This causes the movable contact piece 9 to move to the open position, and the movable contact 9a opens from the fixed contact 8a.

In the electromagnetic relay 100 described above, the position of the hinge spring 5 is restricted by the fixed iron core 43, which is a magnetic material. Therefore, compared to when the hinge spring 5 is fixed by the spool 41, case 2, etc., it is less susceptible to environmental dimensional changes and assembly tolerances, and the hinge spring 5 can be positioned with high precision. As a result, it is possible to improve the positioning precision of the movable iron piece 6 connected to the hinge spring 5. This makes it possible to improve the positioning precision of the movable iron piece 6 with respect to the attraction surface 44c to which the movable iron piece 6 is attracted.

The above describes an embodiment of an electromagnetic relay according to one aspect of the present invention, but the present invention is not limited to the above embodiment, and various modifications are possible without departing from the gist of the invention.

The shapes or arrangements of the case 2, contact device 3, drive unit 4, hinge spring 5, movable iron piece 6, and pressing member 21 may be changed. FIG. 6 is a schematic diagram of the inside of an electromagnetic relay 100 according to a modified example, viewed from the front. The pressing member 121 shown in FIG. 6 extends in the vertical direction and is connected to the movable iron piece 6 and the movable contact piece 9. In the example shown in FIG. 6, the contact device 3 is positioned lower than in the above embodiment. Because the pressing member 121 extends in the vertical direction, a sufficient insulation distance can be ensured between the contact device 3 and the movable iron piece 6.

As shown in FIG. 7, the hinge spring 5 and the movable iron piece 6 may be connected to each other by crimping. Alternatively, as shown in FIG. 8, the movable iron piece 6 may be connected to the hinge spring 5 by an insertion hole 152 into which the movable iron piece 6 is inserted. In the above embodiment, the movable iron piece 6 is pressed into the connection hole 52a, but as shown in FIG. 9, the hinge spring 5 may be formed with a hook portion 6c that is hooked into the connection hole 52a to connect the hinge spring 5 and the movable iron piece 6. The hook portion 6c has a shape with a tip bent upward.

10 and 11 are schematic cross-sectional views of the driving unit 4 and its periphery according to a modified example. In FIG. 11, only the spool 41, the coil 42, and the yoke 44 are shown in cross section for ease of explanation. As shown in FIG. 10 and FIG. 11, the hinge spring 5 may be restricted in position to the fixed core 43 by engaging the engaged portion 53 formed on the hinge spring 5 with the engaging portion 43d formed on the outer circumferential surface of the main body portion 43a of the fixed core 43. The engaging portion 43d is recessed and formed on the outer circumferential surface of the main body portion 43a. The engaged portion 53 is disposed inside the insertion hole 41b. The engaged portion 53 is sandwiched between the bobbin 41a and the main body portion 43a. As shown in FIG. 11, the engaged portion 53 may be formed to surround the outer circumferential surface of the main body portion 43a. In the example shown in FIG. 11, the engaged portion 53 is formed to surround the front side, rear side, right side, and part of the left side of the main body portion 43a. In addition, in the modified example shown in Figures 10 and 11, the flange portion 43b is omitted.

The present invention makes it possible to improve the positioning accuracy of the movable iron piece connected to the hinge spring in an electromagnetic relay.

Reference Signs List 4: Drive section 5: Hinge spring 6: Movable iron piece 6b: Recess 6c: Hook section 41: Spool 41a: Bobbin 41b: Insertion hole 42: Coil 43: Fixed iron core 43a: Main body section 43b: Flange section 43d: Engagement section 44: Yoke 44c: Attractive surface 51: Fitting section 52: Connection section 52a: Connection hole 52b: Press-fit protrusion 53: Engaged section 152: Insertion hole 100: Electromagnetic relay

Claims (9)

A movable iron piece,
A drive unit including a coil and a fixed core disposed inside the coil, the drive unit moving the movable iron piece by electromagnetic force;
a hinge spring including a connecting portion to which the movable iron piece is connected, the hinge spring being disposed in contact with the fixed iron core and being positionally restricted by the fixed iron core, and biasing the movable iron piece in a direction away from the fixed iron core;
Equipped with
The hinge spring further includes a fitting portion that fits onto an outer circumferential surface of the fixed core,
The drive portion further includes a spool.
the spool includes a bobbin around which the coil is wound, the bobbin having an insertion hole into which the fixed core is inserted,
the fixed core includes a main body portion inserted into the insertion hole, and a flange portion having a diameter larger than a diameter of the insertion hole and formed at an end of the main body portion,
The fitting portion of the hinge spring is sandwiched between the bobbin of the spool and the flange portion of the fixed core.
Electromagnetic relay. A movable iron piece,
a driving unit including a coil and a fixed core disposed inside the coil, the driving unit moving the movable iron piece by electromagnetic force;
a hinge spring including a connecting portion to which the movable iron piece is connected, the hinge spring being disposed in contact with the fixed iron core and being positionally restricted by the fixed iron core, and biasing the movable iron piece in a direction away from the fixed iron core;
Equipped with
the drive portion further includes a spool;
the spool includes a bobbin around which the coil is wound, the bobbin having an insertion hole into which the fixed core is inserted,
the fixed core includes a main body portion inserted into the insertion hole and an engagement portion formed on an outer circumferential surface of the main body portion,
The hinge spring further includes an engaged portion that is disposed inside the insertion hole and engages with the engaging portion.
Electromagnetic relay. The engaged portion of the hinge spring is formed to surround an outer circumferential surface of the main body portion of the fixed core.
3. An electromagnetic relay as claimed in claim 2 . The engaged portion of the hinge spring is sandwiched between the bobbin of the spool and the main body portion of the fixed core.
4. An electromagnetic relay according to claim 2 or 3 . The connecting portion of the hinge spring includes an insertion hole into which the movable iron piece is inserted.
5. An electromagnetic relay according to claim 1. The connection portion of the hinge spring includes a connection hole through which a portion of the movable iron piece passes,
The movable iron piece includes a hook portion that is hooked onto the connecting hole.
6. An electromagnetic relay according to claim 1. One of the connecting portion and the movable iron piece of the hinge spring includes a press-fit protrusion,
The other of the connecting portion and the movable iron piece of the hinge spring includes a recess into which the press-fit protrusion is press-fitted.
6. An electromagnetic relay according to claim 1. When the movable iron piece is moved by the electromagnetic force, the movable iron piece rotates about the fixed iron core or the connecting portion as a fulcrum.
8. An electromagnetic relay according to any one of claims 1 to 7 . the driving unit further includes a yoke coupled to the fixed core and surrounding at least a portion of the coil;
The yoke includes an attraction surface that attracts the movable iron piece by the electromagnetic force.
9. An electromagnetic relay according to any one of claims 1 to 8 .

Images