Electromagnetic relay

Abstract

The present invention provides an electromagnetic relay that ensures stable power supply even if the contact disappears. A movable contact piece can move in an opening direction and a closing direction relative to a first fixed terminal and a second fixed terminal. The first movable contact is connected to the movable contact piece. The first movable contact is arranged relative to the first fixed contact. The second movable contact is connected to the movable contact piece. The second movable contact is arranged relative to the second fixed contact. At least one of the first fixed contact and the first movable contact has a material property different from that of at least one of the second fixed contact and the second movable contact.

Description

Technical Field

[0001] The invention relates to an electromagnetic relay. Background Art

[0002] For example, as shown in Patent Document 1, in an electromagnetic relay, there is an electromagnetic relay having a movable contact piece, a movable contact point, a fixed contact point, and a fixed terminal. The movable contact point is connected to the movable contact piece. The movable contact piece moves between an open position and a closed position. When the movable contact piece is in the open position, the movable contact point is separated from the fixed contact point. When the movable contact piece is in the closed position, the movable contact point contacts the fixed contact point. As a result, the fixed terminal and the movable contact piece are energized.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2017-50274

[0004] If an overcurrent flows through the electromagnetic relay, the contact may disappear. If the contact disappears, a gap is generated between the fixed terminal and the movable contact piece, making it difficult to stably energize the fixed terminal and the movable contact piece. Summary of the invention

[0005] An object of the present disclosure is to ensure stable energization in an electromagnetic relay even if a contact point disappears.

[0006] An electromagnetic relay according to one embodiment comprises a first fixed terminal, a first fixed contact, a second fixed terminal, a second fixed contact, a movable contact piece, a first movable contact and a second movable contact. The first fixed contact is connected to the first fixed terminal. The second fixed contact is connected to the second fixed terminal. The movable contact piece can move in an opening direction and a closing direction relative to the first fixed terminal and the second fixed terminal. The first movable contact is connected to the movable contact piece. The first movable contact is arranged relative to the first fixed contact. The second movable contact is connected to the movable contact piece. The second movable contact is arranged relative to the second fixed contact. At least one of the first fixed contact and the first movable contact has a material property different from that of at least one of the second fixed contact and the second movable contact.

[0007] In the electromagnetic relay of this aspect, even if an overcurrent flows, at least one of the first fixed contact and the first movable contact and at least one of the second fixed contact and the second movable contact can be made to disappear at different times, thereby ensuring stable current flow even if some contacts disappear.

[0008] At least one of the first fixed contact and the first movable contact may have a melting point different from that of at least one of the second fixed contact and the second movable contact. In this case, due to the difference in melting points, at least one of the first fixed contact and the first movable contact and at least one of the second fixed contact and the second movable contact can disappear at different times.

[0009] At least one of the first fixed contact and the first movable contact may have a resistance different from that of at least one of the second fixed contact and the second movable contact. In this case, due to the difference in resistance, at least one of the first fixed contact and the first movable contact and at least one of the second fixed contact and the second movable contact can disappear at different times.

[0010] At least one of the first fixed contact and the first movable contact may also include a conductive material of a different type from that of at least one of the second fixed contact and the second movable contact. In this case, due to the difference in the type of conductive material, at least one of the first fixed contact and the first movable contact and at least one of the second fixed contact and the second movable contact can disappear at different times.

[0011] The first fixed contact may be made of a first material. The second fixed contact may be made of a second material different from the first material. In this case, the time when the first fixed contact disappears can be different from the time when the second fixed contact disappears.

[0012] The first movable contact may be made of a first material. The second movable contact may be made of a second material different from the first material. In this case, the time when the first movable contact disappears can be different from the time when the second movable contact disappears.

[0013] The electromagnetic relay may also include a movable mechanism and a driving device. The movable mechanism may also support the movable contact piece in a manner that it can move in the opening direction and the closing direction. The driving device may also move the movable mechanism. The driving mechanism may also include a coil, a fixed iron core and a movable iron core. The fixed iron core may also be arranged in the coil. The movable iron core may also be opposite to the fixed iron core and connected to the movable mechanism. When the movable iron core is in contact with the fixed iron core, the first movable contact may be in contact with the first fixed contact, and the second movable contact may be in contact with the second fixed contact.

[0014] The contact tracking of the movable contact piece can also be smaller than the sum of the lengths of the first fixed contact and the first movable contact in the moving direction of the movable contact piece and / or the sum of the lengths of the second fixed contact and the second movable contact in the moving direction of the movable contact piece. In this case, the contact pressure of the contact can be increased by contact tracking. In addition, when the contact tracking and the size of the contact are in the above-mentioned relationship, if all the contacts are burned at the same time, a gap is likely to be generated between the first and second fixed terminals and the movable contact piece. However, in the electromagnetic relay of this method, even if an overcurrent flows, the time when at least one of the first fixed contact and the first movable contact and at least one of the second fixed contact and the second movable contact disappear can be different from each other. Thus, even if a part of the contacts disappear, stable power supply can be ensured.

[0015] According to the present invention, in the electromagnetic relay, stable energization can be ensured even if the contact point disappears. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a side cross-sectional view showing the electromagnetic relay in the OFF state according to the embodiment.

[0017] Figure 2 It is a side cross-sectional view showing the electromagnetic relay in a closed state.

[0018] Figure 3 This is an enlarged view of the contact device when the movable contact begins to contact the fixed contact.

[0019] Figure 4 It is an enlarged view of the contact device when the movable mechanism is in the closed position.

[0020] Figure 5 It is a side cross-sectional view showing an electromagnetic relay according to a modified example.

[0021] Description of reference numerals:

[0022] 4: driving device; 12: second fixed terminal; 10: movable mechanism; 11: first fixed terminal; 13: movable contact piece; 14: first fixed contact; 15: second fixed contact; 16: first movable contact; 17: second movable contact; 31: movable iron core; 32: coil; 33: fixed iron core. DETAILED DESCRIPTION

[0023] Hereinafter, an electromagnetic relay 1 according to an embodiment will be described with reference to the drawings. Figure 1 1 is a side cross-sectional view showing an electromagnetic relay 1 according to an embodiment. Figure 1 As shown, the electromagnetic relay 1 includes a contact device 2 , a housing 3 , and a drive device 4 .

[0024] In the following description, up, down, left, and right directions refer to Figure 1 Specifically, the direction from the drive device 4 toward the contact device 2 is defined as the upper direction. The direction from the contact device 2 toward the drive device 4 is defined as the lower direction. Figure 1 In the diagram, the direction intersecting the up-down direction is defined as the left-right direction. The direction intersecting the up-down direction and the left-right direction is defined as the front-back direction. Figure 1 However, these directions are defined for the convenience of explanation and do not limit the configuration direction of the electromagnetic relay 1.

[0025] The contact device 2 is arranged in the housing 3. The contact device 2 includes a movable mechanism 10, a first fixed terminal 11, a second fixed terminal 12, a movable contact piece 13, a first fixed contact 14, a second fixed contact 15, a first movable contact 16, and a second movable contact 17. The first fixed terminal 11 and the second fixed terminal 12 are made of a conductive material such as copper or a copper alloy. The first fixed contact 14 is connected to the first fixed terminal 11. The second fixed contact 15 is connected to the second fixed terminal 12. The first fixed contact 14 and the second fixed contact 15 are arranged to be separated from each other in the left-right direction.

[0026] The first fixed terminal 11 includes a first contact support portion 21 and a first external terminal portion 22. The first contact support portion 21 is opposite to the movable contact piece 13. The first fixed contact 14 is connected to the first contact support portion 21. The first external terminal portion 22 is connected to the first contact support portion 21. The first external terminal portion 22 protrudes outward from the housing 3.

[0027] The second fixed terminal 12 includes a second contact support portion 23 and a second external terminal portion 24. The second contact support portion 23 is opposite to the movable contact piece 13. The second fixed contact 15 is connected to the second contact support portion 23. The second external terminal portion 24 is connected to the second contact support portion 23. The second external terminal portion 24 protrudes outward from the housing 3. In detail, the first external terminal portion 22 and the second external terminal portion 24 protrude upward from the housing 3.

[0028] The movable contact piece 13 is formed of a conductive material such as copper or copper alloy. The movable contact piece 13 extends in the left-right direction. The movable contact piece 13 is disposed opposite to the first contact support portion 21 of the first fixed terminal 11 and the second contact support portion 23 of the second fixed terminal 12 in the vertical direction.

[0029] The movable contact piece 13 is configured to be movable in a closing direction Z1 and an opening direction Z2. The closing direction Z1 is a direction in which the movable contact piece 13 approaches the first fixed terminal 11 and the second fixed terminal 12 ( Figure 1The disconnection direction Z2 is the direction in which the movable contact piece 13 moves away from the first fixed terminal 11 and the second fixed terminal 12 ( Figure 1 ).

[0030] The first movable contact 16 and the second movable contact 17 are connected to the movable contact piece 13. The first movable contact 16 and the second movable contact 17 are arranged to be separated in the left-right direction. The first movable contact 16 faces the first fixed contact 14 in the up-down direction. The second movable contact 17 faces the second fixed contact 15 in the up-down direction.

[0031] The movable mechanism 10 supports the movable contact piece 13. The movable mechanism 10 is configured to be movable in the closing direction Z1 and the disconnecting direction Z2 together with the movable contact piece 13. The movable mechanism 10 includes a drive shaft 19, a first holding member 25, a second holding member 26, and a contact spring 27. The drive shaft 19 extends in the up-down direction. The drive shaft 19 is connected to the movable contact piece 13. The drive shaft 19 extends downward from the movable contact piece 13. A hole 13a is provided in the movable contact piece 13. The drive shaft 19 is inserted into the hole 13a. The movable contact piece 13 can move relative to the drive shaft 19 in the closing direction Z1 and the disconnecting direction Z2.

[0032] The drive shaft 19 is arranged to be movable between a closed position and an open position. Figure 1 Indicates the drive shaft 19 in the disconnected position. Figure 1 As shown, when the drive shaft 19 is in the off position, the movable contacts 16 , 17 are separated from the fixed contacts 14 , 15 . Figure 2 The drive shaft 19 is shown in the closed position. Figure 2 As shown, when the drive shaft 19 is in the closed position, the movable contacts 16 , 17 are in contact with the fixed contacts 14 , 15 .

[0033] The first holding member 25 is fixed to the drive shaft 19. The contact spring 27 is disposed between the movable contact piece 13 and the first holding member 25. The contact spring 27 urges the movable contact piece 13 in the closing direction Z1 when the movable contacts 16 and 17 are in contact with the fixed contacts 14 and 15. The second holding member 26 is fixed to the drive shaft 19. The movable contact piece 13 is located between the second holding member 26 and the contact spring 27.

[0034] The driving device 4 moves the movable contact piece 13 by electromagnetic force. The driving device 4 moves the movable mechanism 10 in the closing direction Z1 and the opening direction Z2. Thus, the driving device 4 moves the movable contact piece 13 in the closing direction Z1 and the opening direction Z2. The driving device 4 includes a movable iron core 31, a coil 32, a fixed iron core 33, a yoke 34 and a return spring 35.

[0035] The movable iron core 31 is connected to the drive shaft 19. The movable iron core 31 is configured to be movable in the closing direction Z1 and the opening direction Z2. The coil 32 is energized to generate an electromagnetic force that moves the movable iron core 31 in the closing direction Z1. The fixed iron core 33 is arranged relative to the movable iron core 31. The return spring 35 is arranged between the movable iron core 31 and the fixed iron core 33. The return spring 35 applies force to the movable iron core 31 in the opening direction Z2.

[0036] The yoke 34 is arranged so as to surround the coil 32. The yoke 34 is arranged on the magnetic path formed by the coil 32. The yoke 34 is arranged above the coil 32, on the side of the coil 32, and below the coil 32.

[0037] Next, the operation of the electromagnetic relay 1 is described. When the coil 32 is not energized, the drive device 4 is not excited. In this case, the drive shaft 19 and the movable iron core 31 are pressed in the disconnection direction Z2 by the elastic force of the return spring 35. Therefore, the drive shaft 19 is located Figure 1 In this state, the movable contact piece 13 is also pressed in the disconnection direction Z2 via the movable mechanism 10. Therefore, when the drive shaft 19 is in the disconnection position, the first movable contact 16 and the second movable contact 17 are separated from the first fixed contact 14 and the second fixed contact 15.

[0038] When the coil 32 is energized, the drive device 4 is excited. In this case, the movable iron core 31 overcomes the elastic force of the return spring 35 and moves in the closing direction Z1 by the electromagnetic force of the coil 32. As a result, the drive shaft 19 and the movable contact piece 13 move together in the closing direction Z1. Figure 2 As shown in FIG. 1 , the drive shaft 19 moves toward the closed position. As a result, when the drive shaft 19 is in the closed position, the first movable contact 16 and the second movable contact 17 contact the first fixed contact 14 and the second fixed contact 15, respectively.

[0039] Specifically, when the drive shaft 19 moves from the open position to the closed position, Figure 3 As shown in FIG. 1 , before the drive shaft 19 reaches the closed position, the first movable contact 16 and the second movable contact 17 are in contact with the first fixed contact 14 and the second fixed contact 15, respectively. As a result, the movement of the movable contact piece 13 in the closing direction Z1 is restricted. In this state, the movable iron core 31 has not yet contacted the fixed iron core 33, but is separated from the fixed iron core 33. Therefore, the movable iron core 31 can further move in the closing direction Z1. Therefore, as shown in FIG. Figure 4As shown in FIG. 1 , if the drive shaft 19 further moves in the closing direction Z1, the drive shaft 19 moves in the closing direction Z1 relative to the movable contact piece 13. As a result, the distance between the first holding member 25 and the movable contact piece 13 becomes smaller, and the contact spring 27 is compressed. Therefore, when the drive shaft 19 is in the closed position, the contact spring 27 applies force to the movable contact piece 13 in the closing direction Z1. Figure 2 As shown, when the drive shaft 19 is in the closed position, the movable iron core 31 is in contact with the fixed iron core 33. Thus, the movement of the drive shaft 19 in the closing direction Z1 is restricted.

[0040] exist Figure 4 In FIG. 1 , “A1” indicates contact tracking. Contact tracking A1 is the distance between the start contact position and the closed position. The start contact position is the position of the drive shaft 19 when the first movable contact 16 and the second movable contact 17 first contact the first fixed contact 14 and the second fixed contact 15 .

[0041] The contact point tracking A1 of the movable contact piece 13 is smaller than the sum A2 of the lengths of the first fixed contact 14 and the first movable contact 16 in the moving direction of the movable contact piece 13. The contact point tracking A1 of the movable contact piece 13 is smaller than the sum A3 of the lengths of the second fixed contact 15 and the second movable contact 17 in the moving direction of the movable contact piece 13.

[0042] When the current to the coil 32 stops and the coil 32 is demagnetized, the movable iron core 31 is pressed in the disconnection direction Z2 by the elastic force of the return spring 35. As a result, the drive shaft 19 and the movable contact piece 13 move in the disconnection direction Z2 together. Figure 1 As shown in FIG. 1 , the movable mechanism 10 moves to the OFF position. As a result, when the movable mechanism 10 is in the OFF position, the first movable contact 16 and the second movable contact 17 are separated from the first fixed contact 14 and the second fixed contact 15.

[0043] In the electromagnetic relay 1 of the present embodiment, the first fixed contact 14 and the first movable contact 16 are made of a first material. The second fixed contact 15 and the second movable contact 17 are made of a second material. The first material has material properties different from those of the second material. Specifically, the first material is a conductive material different from that of the second material. Therefore, the first fixed contact 14 and the first movable contact 16 have melting points different from those of the second fixed contact 15 and the second movable contact 17.

[0044] The first material and the second material can be selected from materials known as contact materials. For example, the first material is a conductive material such as silver, a silver alloy, a copper alloy, or a tungsten alloy. The second material is a conductive material such as silver, a silver alloy, a copper alloy, or a tungsten alloy, which is different from the first material.

[0045] In the electromagnetic relay 1 of the present embodiment described above, the first fixed contact 14 and the first movable contact 16 have material properties different from those of the second fixed contact 15 and the second movable contact 17. Therefore, even if an overcurrent flows, the first fixed contact 14 and the first movable contact 16 can be made to disappear at different times from the second fixed contact 15 and the second movable contact 17. Thus, even if a part of the contacts disappears, it is possible to suppress the generation of a gap between the fixed terminals 11, 12 and the movable contact piece 13. Thus, stable energization can be ensured between the fixed terminals 11, 12 and the movable contact piece 13.

[0046] In the electromagnetic relay 1 of the present embodiment, the contact trace A1 of the movable contact piece 13 is shorter than the sum of the lengths A2 and A3 of the fixed contacts 14 and 15 and the movable contacts 16 and 17, respectively. Therefore, if the fixed contacts 14 and 15 and the movable contacts 16 and 17 all disappear, a gap is generated between the fixed terminals 11 and 12 and the movable contact piece 13. However, in the electromagnetic relay of the present embodiment, even if an overcurrent flows, the first fixed contact 14 and the first movable contact 16 can disappear at different times from the second fixed contact 15 and the second movable contact 17. Thus, stable energization can be ensured between the fixed terminals 11 and 12 and the movable contact piece 13.

[0047] As mentioned above, although one embodiment of the present invention has been described, the present invention is not limited to the above-mentioned embodiment, and various modifications can be made without departing from the gist of the invention.

[0048] The first fixed contact 14 and the second fixed contact 15 may be made of the same material. The first movable contact 16 and the second movable contact 17 may also be made of the same material. The first fixed contact 14 and the second fixed contact 15 may be made of a material different from that of the first movable contact 16 and the second movable contact 17.

[0049] In the above-mentioned embodiment, the different material properties are melting points. However, the different material properties may also be other properties such as resistance. The different material properties may also be achieved by the type of surface treatment or the difference in materials. Alternatively, the different material properties may also be achieved by the presence or absence of surface treatment. The surface treatment may be, for example, plating or cladding.

[0050] In the above-mentioned embodiment, the movable contact piece 13 is moved in the closing direction Z1 by pushing out the drive shaft 19 from the side of the drive device 4 by the drive device 4. In addition, the movable contact piece 13 is moved in the disconnecting direction Z2 by pulling the drive shaft 19 into the side of the drive device 4 by the drive device 4. However, the movement direction of the drive shaft 19 for opening and closing the contacts may be opposite to that in the above-mentioned embodiment. That is, the movable contact piece 13 may be moved in the closing direction Z1 by pulling the drive shaft 19 into the side of the drive device 4 by the drive device 4. The movable contact piece 13 may be moved in the disconnecting direction Z2 by pushing out the drive shaft 19 from the side of the drive device 4 by the drive device 4. That is, the closing direction Z1 and the disconnecting direction Z2 may be opposite to those in the above-mentioned embodiment.

[0051] The shape or arrangement of the first fixed terminal 11, the second fixed terminal 12 or the movable contact piece 13 may also be changed. Figure 5 As shown, the first external terminal portion 22 and the second external terminal portion 24 may protrude from the housing 3 in the left-right direction. Alternatively, the first external terminal portion 22 and the second external terminal portion 24 may protrude from the housing 3 in the front-back direction. The shape or arrangement of the movable iron core 31, the coil 32, the fixed iron core 33 or the yoke 34 may also be changed. The shape or arrangement of the first fixed contact 14, the second fixed contact 15, the first movable contact 16, and the second movable contact 17 may also be changed.

[0052] The first fixed contact 14 may be separate from the first fixed terminal 11, or may be integrated. The second fixed contact 15 may be separate from the second fixed terminal 12, or may be integrated. The first movable contact 16 may be separate from the movable contact piece 13, or may be integrated. The second movable contact 17 may be separate from the movable contact piece 13, or may be integrated.

[0053] The contact point tracking A1 of the movable contact piece 13 may also be greater than the sum A2 of the lengths of the first fixed contact 14 and the first movable contact 16 in the moving direction of the movable contact piece 13. The contact point tracking A1 of the movable contact piece 13 may also be greater than the sum A3 of the lengths of the second fixed contact 15 and the second movable contact 17 in the moving direction of the movable contact piece 13. Alternatively, the contact point tracking A1 of the movable contact piece 13 may also be omitted.

[0054] Possibility of industrial application

[0055] According to the present disclosure, in the electromagnetic relay, stable energization can be ensured even if the contact point disappears.

Claims

1. An electromagnetic relay, characterized in that: have: The first fixed terminal; a first fixed contact connected to the first fixed terminal; The second fixed terminal; a second fixed contact connected to the second fixed terminal; A movable contact piece, which can move in an opening direction and a closing direction relative to the first fixed terminal and the second fixed terminal; a first movable contact connected to the movable contact piece and arranged opposite to the first fixed contact; as well as a second movable contact connected to the movable contact piece and arranged opposite to the second fixed contact; At least one of the first fixed contact and the first movable contact has a material property different from that of at least one of the second fixed contact and the second movable contact, The contact tracking of the movable contact piece is smaller than the sum of the lengths of the first fixed contact and the first movable contact in the moving direction of the movable contact piece and / or the sum of the lengths of the second fixed contact and the second movable contact in the moving direction of the movable contact piece, and the contact tracking is the distance between the starting contact position and the closing position of the contact.

2. The electromagnetic relay according to claim 1, characterized in that: At least one of the first fixed contact and the first movable contact has a melting point different from that of at least one of the second fixed contact and the second movable contact.

3. The electromagnetic relay according to claim 1 or 2, characterized in that: At least one of the first fixed contact and the first movable contact has a resistance different from that of at least one of the second fixed contact and the second movable contact.

4. The electromagnetic relay according to claim 1 or 2, characterized in that: At least one of the first fixed contact and the first movable contact includes a conductive material of a different type from that of at least one of the second fixed contact and the second movable contact.

5. The electromagnetic relay according to claim 1 or 2, characterized in that: The first fixed contact is made of a first material, The second fixed contact is made of a second material that is different from the first material.

6. The electromagnetic relay according to claim 1 or 2, characterized in that: The first movable contact is made of a first material, The second movable contact is made of a second material that is different from the first material.

7. The electromagnetic relay according to claim 1 or 2, characterized in that: Also available: a movable mechanism that supports the movable contact piece in a manner that allows movement in the opening direction and the closing direction; as well as a driving device that moves the movable mechanism, The driving device comprises: Coil; a fixed iron core disposed in the coil; and The movable iron core is opposite to the fixed iron core and connected to the movable mechanism.

8. The electromagnetic relay according to claim 7, characterized in that: In a state where the movable iron core is in contact with the fixed iron core, the first movable contact is in contact with the first fixed contact, and the second movable contact is in contact with the second fixed contact.

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