Electromagnetic relay and system comprising electromagnetic relay

Abstract

An electromagnetic relay comprises a first stationary contact, a first movable contact piece, a first main coil, a magnetic body, and an auxiliary coil. The first movable contact piece includes a first movable contact that faces the first stationary contact. The first movable contact piece is movable between a first position and a second position. When the movable contact piece is at one of the first position and the second position, the first movable contact contacts the first stationary contact. When the first movable contact piece is at the other position of the first position and the second position, the movable contact is separated from the stationary contact. When the first main coil is excited, the first movable contact piece is moved from the first position to the second position. The magnetic body attracts the first movable contact piece toward the first position. When the auxiliary coil is excited, a magnetic field is generated in a direction in which the magnetic field of the magnetic body is strengthened or weakened.

Description

Electromagnetic relay and system including the electromagnetic relay

[0001] The present invention relates to an electromagnetic relay and a system including the electromagnetic relay.

[0002] In an electromagnetic relay, contacts are opened and closed by moving a movable contact piece that holds the contacts by the magnetic force from a coil. For example, in Patent Document 1, the electromagnetic relay includes a movable contact piece, a drive shaft, a coil, a fixed iron core, and a movable iron core. The movable contact piece is connected to the movable iron core via the drive shaft. The movable iron core and the fixed iron core are arranged in the coil. When the coil is energized, the movable iron core moves by the magnetic force of the coil. Thereby, the movable contact piece moves, and the contacts come into contact with or separate from each other.

[0003] Japanese Patent Application Laid-Open No. 2024-014554

[0004] In the above electromagnetic relay, even when the coil is not excited, the movable contact piece may move due to an external impact. Therefore, for example, it is conceivable to improve the shock resistance by attracting the movable contact piece in a direction opposite to the magnetic force of the coil by a magnetic body. However, when a magnetic body is provided in the electromagnetic relay, the movable contact piece is also affected by the magnetic force of the magnetic body when moving the movable contact piece by the coil. Therefore, in order to increase the magnetic force of the coil, the coil becomes larger. An object of the present invention is to improve the shock resistance in an electromagnetic relay and to miniaturize the coil.

[0005] An electromagnetic relay according to one aspect of the present invention comprises a first fixed contact, a first movable contact piece, a first main coil, a magnetic material, and an auxiliary coil. The first movable contact piece includes a first movable contact facing the first fixed contact. The first movable contact piece is movable between a first position and a second position. When the first movable contact piece is in one position between the first and second positions, the first movable contact contacts the first fixed contact. When the first movable contact piece is in the other position between the first and second positions, the first movable contact separates from the first fixed contact. When the first main coil is energized, it moves the first movable contact piece from the first position to the second position. The magnetic material attracts the first movable contact piece toward the first position. When the auxiliary coil is energized, it generates a magnetic field that strengthens or weakens the magnetic field of the magnetic material.

[0006] In the electromagnetic relay according to this embodiment, when the first movable contact piece is in the first position, the auxiliary coil generates a magnetic field in a direction that strengthens the magnetic field of the magnetic material, thereby improving shock resistance. Furthermore, since shock resistance can be ensured even if the magnetic force of the magnetic material is reduced, the influence of the magnetic material on the first movable contact piece is reduced. As a result, the first main coil can be miniaturized. Alternatively, when the first movable contact piece moves from the first position to the second position, the auxiliary coil can be used to generate a magnetic field in a direction that weakens the magnetic field of the magnetic material, thereby assisting the main coil. As a result, shock resistance can be improved by the magnetic material, and the main coil can be miniaturized.

[0007] According to the present invention, shock resistance can be improved in electromagnetic relays, and the coil can be made smaller.

[0008] This is a cross-sectional view of an electromagnetic relay according to the first embodiment. This is a cross-sectional view of an electromagnetic relay according to the first embodiment. This is a block diagram showing the control system of the electromagnetic relay according to the first embodiment. This is a table showing the control of the main coil and the auxiliary coil. This is an explanatory diagram of the operation of the electromagnetic relay according to the first embodiment. This is an explanatory diagram of the operation of an electromagnetic relay according to the first embodiment. This is an explanatory diagram of the operation of an electromagnetic relay according to the first embodiment. This is an explanatory diagram of the operation of an electromagnetic relay according to the first embodiment. This is an explanatory diagram of the operation of an electromagnetic relay according to the first embodiment. This is an explanatory diagram of the operation of an electromagnetic relay according to the first embodiment. This is an explanatory diagram of the operation of an electromagnetic relay according to the first embodiment. This is an explanatory diagram of the operation of an electromagnetic relay according to the first embodiment. This is a cross-sectional view of an electromagnetic relay according to the second embodiment. This is a cross-sectional view of an electromagnetic relay according to the second embodiment. This is a cross-sectional view of an electromagnetic relay according to the second embodiment. This is a cross-sectional view of an electromagnetic relay according to the second embodiment. This is a block diagram showing the control system of the electromagnetic relay according to the second embodiment. This is a table showing the control of the first main coil, the second main coil and the auxiliary coil. This is an explanatory diagram of the operation of an electromagnetic relay according to the second embodiment. This is an explanatory diagram of the operation of an electromagnetic relay according to the second embodiment. This is an explanatory diagram of the operation of an electromagnetic relay according to the second embodiment. This is an explanatory diagram of the operation of an electromagnetic relay according to the second embodiment. This is an explanatory diagram of the operation of an electromagnetic relay according to the second embodiment. This is an explanatory diagram of the operation of an electromagnetic relay according to the second embodiment. This is an explanatory diagram of the operation of the electromagnetic relay according to the second embodiment. This is an explanatory diagram of the operation of the electromagnetic relay according to the second embodiment. This is an explanatory diagram of the operation of the electromagnetic relay according to the second embodiment. This is an explanatory diagram of the operation of the electromagnetic relay according to the second embodiment.

[0009] Hereinafter, an electromagnetic relay according to an embodiment of the present invention will be described with reference to the drawings. Figures 1 and 2 are cross-sectional views of an electromagnetic relay 1 according to the first embodiment. As shown in Figure 1, the electromagnetic relay 1 comprises a housing 2, a contact block 3, a movable mechanism 4, a main coil block 5, and an auxiliary coil block 6. The contact block 3, the movable mechanism 4, the main coil block 5, and the auxiliary coil block 6 are arranged inside the housing 2.

[0010] In the following explanation, the direction in which the contact block 3 is positioned relative to the main coil block 5 is defined as upward, and the opposite direction is defined as downward. Also, in Figures 1 and 2, the direction perpendicular to the vertical direction is defined as the left-right direction. However, these directions are used for the sake of explanation and do not limit the arrangement of the electromagnetic relay 1, etc.

[0011] The contact block 3 includes a contact case 11, a right fixed terminal 12, a left fixed terminal 13, and a movable contact piece 14. The right fixed terminal 12 and the left fixed terminal 13 extend from the inside to the outside of the housing 2. The right fixed terminal 12 and the left fixed terminal 13 are made of a conductive material such as copper. The right fixed terminal 12 includes a right fixed contact 15. The left fixed terminal 13 includes a left fixed contact 16. The right fixed contact 15 and the left fixed contact 16 are located inside the contact case 11.

[0012] The movable contact piece 14 is located inside the contact case 11. The movable contact piece 14 extends in the left-right direction. The movable contact piece 14 is located below the right fixed terminal 12 and the left fixed terminal 13. The movable contact piece 14 is made of a conductive material such as copper. The movable contact piece 14 includes a right movable contact 17 and a left movable contact 18. The right movable contact 17 faces the right fixed contact 15. The left movable contact 18 faces the left fixed contact 16.

[0013] The right fixed contact 15 may be integrated with the right fixed terminal 12, or it may be separate. The left fixed contact 16 may be integrated with the left fixed terminal 13, or it may be separate. The right movable contact 17 and the left movable contact 18 may be integrated with the movable contact piece 14, or they may be separate.

[0014] The movable contact piece 14 is movable in a contact direction Z2 and a separation direction Z1. The contact direction Z2 is the direction in which the movable contacts 17 and 18 contact the fixed contacts 15 and 16. The separation direction Z1 is the direction in which the movable contacts 17 and 18 separate from the fixed contacts 15 and 16. In this embodiment, the contact direction Z2 is upward and the separation direction Z1 is downward.

[0015] The movable contact piece 14 is movable between a contact position and an open position. Figure 1 shows the electromagnetic relay 1 when the movable contact piece 14 is in the open position. As shown in Figure 1, when the movable contact piece 14 is in the open position, the movable contacts 17 and 18 are separated from the fixed contacts 15 and 16. Figure 2 shows the electromagnetic relay 1 when the movable contact piece 14 is in the contact position. As shown in Figure 2, when the movable contact piece 14 is in the contact position, the movable contacts 17 and 18 are in contact with the fixed contacts 15 and 16.

[0016] The movable mechanism 4 is connected to the movable contact piece 14. The movable mechanism 4 includes a drive shaft 21, a stopper 22, a holder 23, and a contact spring 24. The drive shaft 21 extends vertically through the movable contact piece 14. The drive shaft 21 is provided to be movable vertically. The drive shaft 21 is connected to the movable contact piece 14 so as to be relatively movable vertically.

[0017] The stopper 22 is fixed to the drive shaft 21 above the movable contact piece 14. The stopper 22 restricts the downward movement of the drive shaft 21 relative to the movable contact piece 14. The holder 23 is fixed to the drive shaft 21 below the movable contact piece 14. The contact spring 24 is positioned between the movable contact piece 14 and the holder 23. The contact spring 24 is a coil spring. The contact spring 24 biases the movable contact piece 14 in the contact direction Z2.

[0018] The main coil block 5 is located below the contact block 3. The main coil block 5 includes a main coil 31, a main spool 32, a fixed iron core 33, a movable iron core 34, a main yoke 35, and a return spring 36. The main coil 31 is wound around the main spool 32. The main coil 31 generates a magnetic force that moves the movable contact piece 14 between a contact position and a separation position. Specifically, when the main coil 31 is energized, it attracts the movable iron core 34 in the contact direction Z2.

[0019] The fixed core 33 and the movable core 34 are arranged inside the main spool 32. The movable core 34 faces the fixed core 33. The movable core 34 is positioned below the fixed core 33. The movable core 34 is fixed to the drive shaft 21. The main yoke 35 is arranged to surround the main coil 31. The return spring 36 is positioned between the movable core 34 and the fixed core 33.

[0020] The auxiliary coil block 6 is located below the main coil block 5. The auxiliary coil block 6 includes a magnetic body 41, an auxiliary spool 42, an auxiliary coil 43, and an auxiliary yoke 44. The auxiliary spool 42 is located at the bottom of the housing 2. The magnetic body 41 is located inside the auxiliary spool 42. The magnetic body 41 is located below the movable iron core 34. The magnetic body 41 is a permanent magnet. The magnetic body 41 generates a magnetic force that attracts the movable contact piece 14 toward the detached position. That is, the magnetic body 41 attracts the movable iron core 34 toward the detached direction Z1.

[0021] The auxiliary coil 43 is wound around the auxiliary spool 42. The auxiliary coil 43 is positioned below the main coil 31. The auxiliary coil 43 is positioned concentrically with the main coil 31. When the auxiliary coil 43 is energized, it generates a magnetic field that strengthens or weakens the magnetic field of the magnetic material 41. The auxiliary yoke 44 is positioned inside the auxiliary spool 42. The auxiliary yoke 44 is attached to the auxiliary spool 42. The auxiliary yoke 44 is positioned above the magnetic material 41. The auxiliary yoke 44 is in contact with the main coil 31. However, the auxiliary yoke 44 may be separated from the main coil 31.

[0022] Figure 1 shows the electromagnetic relay 1 in a state where the main coil 31 is not energized and the main coil block 5 is not energized. When the main coil block 5 is not energized and is not energized, the movable contact piece 14 is in the separated position shown in Figure 1. In this case, the right movable contact 17 is separated from the right fixed contact 15, and the left movable contact 18 is separated from the left fixed contact 16.

[0023] Figure 2 shows the electromagnetic relay 1 in a state where the main coil block 5 is energized by energizing the main coil 31. When the main coil block 5 is energized, the movable iron core 34 moves in the contact direction Z2 together with the drive shaft 21. As a result, the movable contact piece 14 moves to the contact position, and the movable contacts 17 and 18 make contact with the fixed contacts 15 and 16. After the movable contacts 17 and 18 make contact with the fixed contacts 15 and 16, the movable iron core 34 rises further until it makes contact with the fixed iron core 33. As a result, the drive shaft 21 moves further in the contact direction Z2, and the contact spring 24 is compressed by the holder 23.

[0024] Next, the control of the auxiliary coil block 6 will be described. Figure 3 is a block diagram of the control system 200 of the electromagnetic relay 1. As shown in Figure 3, the control system 200 of the electromagnetic relay 1 includes a controller 45. The controller 45 includes, for example, a microcomputer and memory. The controller 45 is connected to the main coil 31 and the auxiliary coil 43. The controller 45 controls the energization of the main coil 31 and the auxiliary coil 43.

[0025] Figure 4 is a table showing the control of the main coil 31 and the auxiliary coil 43. In Figure 4, "ON" indicates that the main coil 31 or the auxiliary coil 43 is energized and excited. "OFF" indicates that the main coil 31 or the auxiliary coil 43 is not energized and is de-energized. "Forward" indicates that the auxiliary coil 43 is energized in the forward direction. Forward direction refers to the direction of the current that generates a magnetic field in the auxiliary coil 43 in the direction that strengthens the magnetic field of the magnetic material 41. "Reverse" indicates that the auxiliary coil 43 is energized in the reverse direction. Reverse direction refers to the direction of the current that generates a magnetic field in the auxiliary coil 43 in the direction that weakens the magnetic field of the magnetic material 41.

[0026] Figure 5 shows the main coil block 5 and auxiliary coil block 6 when the main coil 31 is not energized. As shown in Figure 5, when the main coil 31 is not energized and the movable contact piece 14 is in the separated position shown in Figure 1, the controller 45 energizes the auxiliary coil 43 in the forward direction (control No. 1 in Figure 5). As a result, the attractive force in the separated direction Z1 by the magnetic material 41 and the auxiliary coil 43 is strengthened, and the auxiliary coil 43 generates a magnetic field H2 in a direction that strengthens the magnetic field H1 by the magnetic material 41. Therefore, even if an external shock is applied to the electromagnetic relay 1, contact between the movable contacts 17 and 18 and the fixed contacts 15 and 16 is suppressed. This improves the shock resistance of the electromagnetic relay 1.

[0027] Figure 6 shows the main coil block 5 and auxiliary coil block 6 when the movable contact piece 14 is moved from the open position to the contact position by energizing the main coil 31. As shown in Figure 6, when the controller 45 energizes the main coil 31 to move the movable contact piece 14 from the open position to the contact position, it energizes the auxiliary coil 43 in the opposite direction (control No. 2 in Figure 4). As a result, the auxiliary coil 43 generates a magnetic field H2 in a direction that weakens the magnetic field H1 made by the magnetic material 41. Therefore, the attractive force in the open direction Z1 by the magnetic material 41 and the auxiliary coil 43 is weakened, and the attractive force F1 in the contact direction Z2 made by the main coil 31 can be assisted by the auxiliary coil 43. This makes it possible to miniaturize the main coil 31.

[0028] Figure 7 shows the main coil block 5 and auxiliary coil block 6 just before the movable iron core 34, which has moved in the contact direction Z2, contacts the fixed iron core 33. As shown in Figure 7, the controller 45 energizes the auxiliary coil 43 in the forward direction before the movable iron core 34 contacts the fixed iron core 33 (control No. 3 in Figure 4). As a result, the auxiliary coil 43 generates a magnetic field H2 in a direction that strengthens the magnetic field H1 produced by the magnetic material 41. Therefore, the attractive force in the separation direction Z1 between the magnetic material 41 and the auxiliary coil 43 is strengthened, and the impact force when the movable iron core 34 contacts the fixed iron core 33 is mitigated. As a result, the operating noise of the electromagnetic relay 1 becomes quieter.

[0029] The controller 45 may also stop supplying power to the auxiliary coil 43 before the movable iron core 34 comes into contact with the fixed iron core 33. In this case as well, the impact force when the movable iron core 34 comes into contact with the fixed iron core 33 is mitigated.

[0030] After the movable iron core 34 makes contact with the fixed iron core 33, the controller 45 stops supplying power to the auxiliary coil 43. Alternatively, after the movable iron core 34 makes contact with the fixed iron core 33, the controller 45 may supply power to the auxiliary coil 43 in the reverse direction. This allows the contact state of the contacts to be stably maintained.

[0031] Figure 8 shows the main coil block 5 and auxiliary coil block 6 when the power supply to the main coil 31 is stopped from a state where the main coil 31 is energized. As shown in Figure 8, when the controller 45 moves the movable contact piece 14 from the contact position to the separation position by stopping the power supply to the main coil 31, it energizes the auxiliary coil 43 in the forward direction (control No. 4 in Figure 4). As a result, the auxiliary coil 43 generates a magnetic field H2 in a direction that strengthens the magnetic field H1 made by the magnetic material 41. Therefore, the attractive force in the separation direction Z1 by the magnetic material 41 and the auxiliary coil 43 is strengthened, and the elastic force F2 of the return spring 36 acting on the movable iron core 34 in the separation direction Z1 can be assisted by the auxiliary coil 43.

[0032] Figure 9 shows the main coil block 5 and auxiliary coil block 6 just before the movable contact piece 14 reaches the separation position from the contact position. As shown in Figure 9, the controller 45 stops the power supply to the auxiliary coil 43 just before the movable contact piece 14 reaches the separation position (control No. 5 in Figure 4). This reduces the impact force when the movable iron core 34 or the movable mechanism 4 comes into contact with other members. As a result, the operating noise of the electromagnetic relay 1 becomes quieter.

[0033] Furthermore, the controller 45 may energize the auxiliary coil 43 in the reverse direction just before the movable contact piece 14 reaches the separated position. This causes the auxiliary coil 43 to generate a magnetic field H2 in a direction that weakens the magnetic field H1 produced by the magnetic material 41. As a result, the impact force when the movable iron core 34 or the movable mechanism 4 comes into contact with other members is mitigated.

[0034] The controller 45 may maintain forward current supply to the auxiliary coil 43 even when the main coil 31 is energized while the movable contact piece 14 is in the separated position (control No. 6 in Figure 4). As a result, as shown in Figure 10, the auxiliary coil 43 generates a magnetic field H2 in a direction that strengthens the magnetic field H1 produced by the magnetic material 41. The attractive force F3 due to the magnetic field H1 of the magnetic material 41 and the magnetic field H2 of the auxiliary coil 43 is greater than the attractive force F1 produced by the main coil 31. Therefore, even if the main coil 31 is accidentally energized while the auxiliary coil 43 is energized in the forward direction, the movable iron core 34 will not move. This prevents erroneous operation of the electromagnetic relay 1.

[0035] When the movable contact piece 14 is moved from the open position to the contact position by energizing the main coil 31, the controller 45 may energize the main coil 31 and stop energizing the auxiliary coil 43. In this case, as shown in Figure 11, no magnetic field is generated by the auxiliary coil 43, and the attractive force due to the magnetic field H1 of the magnetic material 41 acts on the movable iron core 34. Also, when the main coil 31 is energized, the attractive force F1 from the main coil 31 acts on the movable iron core 34 in the contact direction Z2. The attractive force F1 from the main coil 31 is greater than the attractive force due to the magnetic field H1 of the magnetic material 41 alone. Therefore, the movable iron core 34 moves in the contact direction Z2. As a result, as shown in Figure 2, the movable contact piece 14 moves to the contact position, and the movable contacts 17 and 18 come into contact with the fixed contacts 15 and 16. In this case as well, the main coil 31 can be made smaller compared to the case where the auxiliary coil 43 is not provided.

[0036] Next, an electromagnetic relay 100 according to the second embodiment will be described. Figure 12 is a cross-sectional view of the electromagnetic relay 100 according to the second embodiment. The electromagnetic relay 100 according to the second embodiment comprises a housing 2, a first relay 1A, a second relay 1B, and an auxiliary coil block 6. The first relay 1A, the second relay 1B, and the auxiliary coil block 6 are arranged inside the housing 2.

[0037] The first relay 1A includes a first contact block 3A, a first movable mechanism 4A, and a first main coil block 5A. The first contact block 3A includes a first contact case 11A, a first right fixed terminal 12A, a first left fixed terminal 13A, and a first movable contact piece 14A. The first right fixed terminal 12A includes a first right fixed contact 15A. The first left fixed terminal 13A includes a first left fixed contact 16A. The first movable contact piece 14A includes a first right movable contact 17A and a first left movable contact 18A.

[0038] The first movable mechanism 4A includes a first drive shaft 21A, a first stopper 22A, a first holder 23A, and a first contact spring 24A. The first main coil block 5A includes a first main coil 31A, a first main spool 32A, a first fixed iron core 33A, a first movable iron core 34A, a first main yoke 35A, and a first return spring 36A. The configuration of these first relays 1A is the same as that of the contact block 3, movable mechanism 4, and main coil block 5 in the first embodiment.

[0039] In the following description, in the first relay 1A, the direction in which the first movable contacts 17A and 18A move away from the first fixed contacts 15A and 16A is defined as the first separation direction Z1A. The direction in which the first movable contacts 17A and 18A make contact with the first fixed contacts 15A and 16A is defined as the first contact direction Z2A. In the first relay 1A, the first separation direction Z1A is downward, and the first contact direction Z2A is upward.

[0040] The second relay 1B has a configuration that is vertically symmetrical to the first relay 1A. The second relay 1B includes a second contact block 3B, a second movable mechanism 4B, and a second main coil block 5B. The second contact block 3B includes a second contact case 11B, a second right fixed terminal 12B, a second left fixed terminal 13B, and a second movable contact piece 14B. The second right fixed terminal 12B includes a second right fixed contact 15B. The second left fixed terminal 13B includes a second left fixed contact 16B. The second movable contact piece 14B includes a second right movable contact 17B and a second left movable contact 18B. The second movable mechanism 4B includes a second drive shaft 21B, a second stopper 22B, a second holder 23B, and a second contact spring 24B. The second main coil block 5B includes a second main coil 31B, a second main spool 32B, a second fixed iron core 33B, a second movable iron core 34B, a second main yoke 35B, and a second return spring 36B. The configuration of these second relays 1B is the same as that of the contact block 3, movable mechanism 4, and main coil block 5 of the first embodiment, except that they are symmetrical in the vertical direction.

[0041] In the following description, in the second relay 1B, the direction in which the second movable contacts 17B and 18B move away from the second fixed contacts 15B and 16B is defined as the second separation direction Z1B. The direction in which the second movable contacts 17B and 18B contact the second fixed contacts 15B and 16B is defined as the second contact direction Z2B. In the second relay 1B, the second separation direction Z1B is upward, and the second contact direction Z2B is downward.

[0042] The auxiliary coil block 6 is positioned between the first relay 1A and the second relay 1B. The auxiliary coil block 6 includes a magnetic material 41, an auxiliary spool 42, and an auxiliary coil 43. The configuration of these auxiliary coil blocks 6 is the same as that of the auxiliary coil block 6 in the first embodiment.

[0043] The magnetic body 41 and the auxiliary coil 43 are arranged between the first main coil 31A and the second main coil 31B. The magnetic body 41 and the auxiliary coil 43 are arranged between the first main yoke 35A and the second main yoke 35B. The magnetic body 41 is arranged between the first movable iron core 34A and the second movable iron core 34B. The magnetic body 41 generates a magnetic field that attracts the first movable iron core 34A in the first separation direction Z1A and attracts the second movable iron core 34B in the second separation direction Z1B.

[0044] The auxiliary coil block 6 includes a first auxiliary yoke 44A and a second auxiliary yoke 44B. The first auxiliary yoke 44A and the second auxiliary yoke 44B are arranged in the auxiliary spool 42. The first auxiliary yoke 44A is arranged above the magnetic body 41. The second auxiliary yoke 44B is arranged below the magnetic body 41.

[0045] Next, the operation of the electromagnetic relay 100 according to the second embodiment will be described. FIG. 12 shows the electromagnetic relay 100 in a state where neither the first main coil 31A nor the second main coil 31B is energized and the first main coil block 5A and the second main coil block 5B are not excited. When the first main coil block 5A is not excited, the first movable contact piece 14A is located at the first separation position shown in FIG. 12. In this case, the first right movable contact 17A is separated from the first right fixed contact 15A, and the first left movable contact 18A is separated from the first left fixed contact 16A. Also, when the second main coil block 5B is not excited, the second movable contact piece 14B is located at the second separation position shown in FIG. 12. In this case, the second right movable contact 17B is separated from the second right fixed contact 15B, and the second left movable contact 18B is separated from the second left fixed contact 16B.

[0046] Figure 13 shows the electromagnetic relay 100 in a state where the first main coil block 5A is energized by energizing the first main coil 31A. In this case, the second main coil 31B is not energized, and the second main coil block 5B is not energized. When the first main coil block 5A is energized, the first movable iron core 34A moves in the first contact direction Z2A together with the first drive shaft 21A. As a result, the first movable contact piece 14A moves to the first contact position shown in Figure 13, and the first movable contacts 17A and 18A come into contact with the first fixed contacts 15A and 16A. When the energization to the first main coil 31A is stopped, the first movable contact piece 14A returns to the first separated position shown in Figure 12 due to the elastic force of the first return spring 36A. As a result, the first movable contacts 17A and 18A separate from the first fixed contacts 15A and 16A.

[0047] Figure 14 shows the electromagnetic relay 100 in a state where the second main coil block 5B is energized by energizing the second main coil 31B. In this case, the first main coil 31A is not energized, and the first main coil block 5A is not energized. When the second main coil block 5B is energized, the second movable iron core 34B moves together with the second drive shaft 21B in the second contact direction Z2B. As a result, the second movable contact piece 14B moves to the second contact position shown in Figure 14, and the second movable contacts 17B and 18B come into contact with the second fixed contacts 15B and 16B. When the energization to the second main coil 31B is stopped, the second movable contact piece 14B returns to the second separated position shown in Figure 12 due to the elastic force of the second return spring 36B. As a result, the second movable contacts 17B and 18B separate from the second fixed contacts 15B and 16B.

[0048] Next, the control of the auxiliary coil block 6 will be described. FIG. 15 is a block diagram showing a control system 300 of the electromagnetic relay 100. FIG. 16 is a table showing the control of the first main coil 31A, the second main coil 31B, and the auxiliary coil 43. As shown in FIG. 15, the control system 300 of the electromagnetic relay 100 includes a controller 45. The configuration of the controller 45 is the same as that of the controller 45 according to the first embodiment. The controller 45 is connected to the first main coil 31A, the second main coil 31B, and the auxiliary coil 43. The controller 45 controls energization of the first main coil 31A, energization of the second main coil 31B, and energization of the auxiliary coil 43.

[0049] FIG. 17 is a diagram showing the first and second main coil blocks 5A and 5B and the auxiliary coil block 6 when neither the first main coil 31A nor the second main coil 31B is energized. As shown in FIG. 17, when the first main coil 31A and the second main coil 31B are not energized and, as shown in FIG. 12, the first movable contact piece 14A is located at the first open position and the second movable contact piece 14B is located at the second open position, the controller 45 energizes the auxiliary coil 43 in the forward direction (Control No. 1 in FIG. 16).

[0050] When the auxiliary coil 43 is energized in the forward direction, the auxiliary coil 43 generates a magnetic field H2 in a direction that strengthens the magnetic field H1 of the magnetic body 41. Therefore, an attractive force due to the magnetic field H1 of the magnetic body 41 and the magnetic field H2 of the auxiliary coil 43 acts on the first movable iron core 34A in the first opening direction Z1A. Also, an attractive force due to the magnetic field H1 of the magnetic body 41 and the magnetic field H2 of the auxiliary coil 43 acts on the second movable iron core 34B in the second opening direction Z1B. Therefore, even if an external impact is applied to the electromagnetic relay 100, in the first relay 1A, contact between the first movable contacts 17A and 18A and the first fixed contacts 15A and 16A is suppressed. Also, in the second relay 1B, contact between the second movable contacts 17B and 18B and the second fixed contacts 15B and 16B is suppressed. Thereby, the impact resistance of the electromagnetic relay 100 is improved.

[0051] Figure 18 shows the first and second main coil blocks 5A, 5B and the auxiliary coil block 6 when the first movable contact piece 14A is moved from the first open position to the first contact position by energizing the first main coil 31A. As shown in Figure 18, when the controller 45 energizes the first main coil 31A to move the first movable contact piece 14A from the first open position to the first contact position, it energizes the auxiliary coil 43 in the opposite direction (control No. 2 in Figure 16). As a result, the auxiliary coil 43 generates a magnetic field H2 in a direction that weakens the magnetic field H1 of the magnetic material 41. Therefore, the attractive force between the magnetic material 41 and the auxiliary coil 43 in the first open direction Z1A is weakened, and the attractive force F1A in the first contact direction Z2A by the first main coil 31A can be assisted by the auxiliary coil 43. As a result, the first main coil 31A can be made smaller. In addition, as in the first embodiment, when the first movable contact piece 14A is moved from the first open position to the first contact position by energizing the first main coil 31A, the controller 45 may energize the first main coil 31A and stop energizing the auxiliary coil 43.

[0052] Figure 19 shows the first and second main coil blocks 5A, 5B and the auxiliary coil block 6 just before the first movable iron core 34A, which has moved in the first contact direction Z2A, contacts the first fixed iron core 33A. As shown in Figure 19, the controller 45 energizes the auxiliary coil 43 in the forward direction before the first movable iron core 34A contacts the first fixed iron core 33A (control No. 3 in Figure 16). As a result, the auxiliary coil 43 generates a magnetic field H2 in a direction that strengthens the magnetic field H1 of the magnetic material 41. Therefore, the attractive force between the magnetic material 41 and the auxiliary coil 43 in the first separation direction Z1A is strengthened, and the impact force when the first movable iron core 34A contacts the first fixed iron core 33A is mitigated. As a result, the operating noise of the electromagnetic relay 100 becomes quieter. The controller 45 may also stop energizing the auxiliary coil 43 before the first movable iron core 34A contacts the first fixed iron core 33A.

[0053] After the first movable iron core 34A makes contact with the first fixed iron core 33A, the controller 45 stops supplying power to the auxiliary coil 43. Alternatively, after the first movable iron core 34A makes contact with the first fixed iron core 33A, the controller 45 may supply power to the auxiliary coil 43 in the reverse direction.

[0054] Figure 20 shows the first and second main coil blocks 5A, 5B and the auxiliary coil block 6 when the current to the first main coil 31A is stopped from a state where current is supplied to the first main coil 31A. As shown in Figure 20, when the controller 45 stops the current to the first main coil 31A and moves the first movable contact piece 14A from the first contact position to the first separation position, it supplies current to the auxiliary coil 43 in the forward direction (control No. 4 in Figure 16). As a result, the auxiliary coil 43 generates a magnetic field H2 in a direction that strengthens the magnetic field H1 of the magnetic material 41. Therefore, the attractive force between the magnetic material 41 and the auxiliary coil 43 in the first separation direction Z1A is strengthened, and the elastic force F2A of the first return spring 36A acting on the first movable iron core 34A in the first separation direction Z1A can be assisted by the auxiliary coil 43.

[0055] Figure 21 shows the first and second main coil blocks 5A, 5B and the auxiliary coil block 6 just before the first movable contact piece 14A reaches the first separation position from the first contact position. As shown in Figure 21, the controller 45 stops the power supply to the auxiliary coil 43 just before the first movable contact piece 14A reaches the first separation position (control No. 5 in Figure 16). This reduces the impact force when the first movable iron core 34A or the first movable mechanism 4A contacts other members. As a result, the operating noise of the electromagnetic relay 100 becomes quieter. Alternatively, the controller 45 may supply power to the auxiliary coil 43 in the reverse direction just before the first movable contact piece 14A reaches the first separation position.

[0056] Figure 22 shows the first and second main coil blocks 5A, 5B and the auxiliary coil block 6 when the second movable contact piece 14B is moved from the second separation position to the second contact position by energizing the second main coil 31B. As shown in Figure 22, when the controller 45 moves the second movable contact piece 14B from the second separation position to the second contact position by energizing the second main coil 31B, it energizes the auxiliary coil 43 in the opposite direction (control No. 6 in Figure 16). As a result, the auxiliary coil 43 generates a magnetic field H2 in a direction that weakens the magnetic field H1 of the magnetic material 41. Therefore, the attractive force between the magnetic material 41 and the auxiliary coil 43 in the second separation direction Z1B is weakened, and the attractive force F1B in the second contact direction Z2B by the second main coil 31B can be assisted by the auxiliary coil 43. As a result, the second main coil 31B can be miniaturized. In addition, as in the first embodiment, when the second movable contact piece 14B is moved from the second open position to the second contact position by energizing the second main coil 31B, the controller 45 may energize the second main coil 31B and stop energizing the auxiliary coil 43.

[0057] Figure 23 shows the first and second main coil blocks 5A, 5B and the auxiliary coil block 6 just before the second movable iron core 34B, which has moved in the second contact direction Z2B, contacts the second fixed iron core 33B. As shown in Figure 23, the controller 45 energizes the auxiliary coil 43 in the forward direction before the second movable iron core 34B contacts the second fixed iron core 33B (control No. 7 in Figure 16). As a result, the auxiliary coil 43 generates a magnetic field H2 in a direction that strengthens the magnetic field H1 of the magnetic material 41. Therefore, the attractive force between the magnetic material 41 and the auxiliary coil 43 in the second separation direction Z1B is strengthened, and the impact force when the second movable iron core 34B contacts the second fixed iron core 33B is mitigated. As a result, the operating noise of the electromagnetic relay 100 becomes quieter. Alternatively, the controller 45 may stop energizing the auxiliary coil 43 before the second movable iron core 34B contacts the second fixed iron core 33B.

[0058] After the second movable iron core 34B makes contact with the second fixed iron core 33B, the controller 45 stops supplying power to the auxiliary coil 43. Alternatively, after the second movable iron core 34B makes contact with the second fixed iron core 33B, the controller 45 may supply power to the auxiliary coil 43 in the reverse direction.

[0059] Figure 24 shows the first and second main coil blocks 5A, 5B and the auxiliary coil block 6 when the current to the second main coil 31B is stopped from a state where current is supplied to the second main coil 31B. As shown in Figure 24, when the controller 45 stops the current to the second main coil 31B and moves the second movable contact piece 14B from the second contact position to the second separation position, it supplies current to the auxiliary coil 43 in the forward direction (control No. 8 in Figure 16). As a result, the auxiliary coil 43 generates a magnetic field H2 in a direction that strengthens the magnetic field H1 of the magnetic material 41. Therefore, the attractive force between the magnetic material 41 and the auxiliary coil 43 in the second separation direction Z1B is strengthened, and the elastic force F2B of the second return spring 36B acting on the second movable iron core 34B in the second separation direction Z1B can be assisted by the auxiliary coil 43.

[0060] Figure 25 shows the first and second main coil blocks 5A, 5B and the auxiliary coil block 6 just before the second movable contact piece 14B reaches the second separation position from the second contact position. As shown in Figure 25, the controller 45 stops the power supply to the auxiliary coil 43 just before the second movable contact piece 14B reaches the second separation position (control No. 9 in Figure 16). This reduces the impact force when the second movable iron core 34B or the second movable mechanism 4B contacts other members. As a result, the operating noise of the electromagnetic relay 100 becomes quieter. Alternatively, the controller 45 may supply power to the auxiliary coil 43 in the reverse direction just before the second movable contact piece 14B reaches the second separation position.

[0061] Furthermore, the controller 45 may maintain forward current supply to the auxiliary coil 43 even when the first main coil 31A and the second main coil 31B are energized while the first movable contact piece 14A is in the first separation position and the second movable contact piece 14B is in the second separation position. As a result, as shown in Figure 26, an attractive force F3A due to the magnetic field H1 of the magnetic material 41 and the magnetic field H2 of the auxiliary coil 43 acts on the first movable iron core 34A in the first separation direction Z1A. Also, an attractive force F3B due to the magnetic field H1 of the magnetic material 41 and the magnetic field H2 of the auxiliary coil 43 acts on the second movable iron core 34B in the second separation direction Z1B.

[0062] The attractive force F3A acting on the first movable iron core 34A due to the magnetic field H1 of the magnetic material 41 and the magnetic field H2 of the auxiliary coil 43 is greater than the attractive force F1A of the first main coil 31A. Therefore, even if the first main coil 31A is mistakenly energized while the auxiliary coil 43 is energized in the forward direction, the first movable iron core 34A will not move. Similarly, the attractive force F3B acting on the second movable iron core 34B due to the magnetic field H1 of the magnetic material 41 and the magnetic field H2 of the auxiliary coil 43 is greater than the attractive force F1B of the second main coil 31B. Therefore, even if the second main coil 31B is mistakenly energized while the auxiliary coil 43 is energized in the forward direction, the second movable iron core 34B will not move. This prevents erroneous operation of the electromagnetic relay 100.

[0063] Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various modifications are possible without departing from the spirit of the invention.

[0064] The configuration of the electromagnetic relay is not limited to that of the above embodiment and may be modified. For example, the electromagnetic relay in the above embodiment is a so-called plunger type. However, the electromagnetic relay 100 is not limited to the plunger type and may be of other types, such as a hinge type. The magnetic material may be a magnetic material other than a permanent magnet.

[0065] In the first embodiment described above, the open position is the first position and the contact position is the second position. That is, the electromagnetic relay 1 according to the first embodiment is a NO (Normally Open) type relay. However, the contact position may be the first position and the open position may be the second position. That is, the electromagnetic relay 1 according to the first embodiment may be an NC (Normally Closed) type relay.

[0066] In the second embodiment described above, the first release position is the first position, the first contact position is the second position, the second release position is the third position, and the second contact position is the fourth position. That is, the electromagnetic relay 100 according to the second embodiment is a NO (Normally Open) type relay. However, the first contact position may be the first position, the first release position may be the second position, the second contact position may be the third position, and the second release position may be the fourth position. That is, the electromagnetic relay 100 according to the second embodiment may be an NC (Normally Closed) type relay.

[0067] According to the present invention, shock resistance can be improved in electromagnetic relays, and the coil can be made smaller.

[0068] 14: Movable contact piece, 15: Right fixed contact, 17: Right movable contact, 21: Drive shaft, 31: Main coil, 32: Main spool, 34: Movable iron core, 41: Magnetic material, 42: Auxiliary spool, 43: Auxiliary coil, 44: Auxiliary yoke, 45: Controller, 14A: First movable contact piece, 14B: Second movable contact piece, 15A: First right fixed contact, 15B: Second right fixed contact, 17A: First right movable contact, 17B: Second right movable contact, 21A: First drive shaft, 21B: Second drive shaft, 31A: First main coil, 31B: Second main coil, 32A: First main spool, 32B: Second main spool, 34A: First movable iron core, 34B: Second movable iron core

Claims

1. An electromagnetic relay comprising: a first fixed contact; a first movable contact facing the first fixed contact, which is movable between a first position and a second position, wherein the first movable contact contacts the first fixed contact at one of the first and second positions, and separates from the first fixed contact at the other of the first and second positions; a first main coil that, when energized, moves the first movable contact from the first position to the second position; a magnetic material that attracts the first movable contact toward the first position; and an auxiliary coil that, when energized, generates a magnetic field in a direction that strengthens or weakens the magnetic field of the magnetic material.

2. The electromagnetic relay according to claim 1, wherein the magnetic material is a permanent magnet.

3. The electromagnetic relay according to claim 1, further comprising an auxiliary spool around which the auxiliary coil is wound, wherein the magnetic material is disposed within the auxiliary spool.

4. The electromagnetic relay according to claim 1, further comprising: a first main spool around which the first main coil is wound; a first drive shaft connected to the first movable contact piece and extending through the first main spool; and a first movable iron core disposed within the first main spool and connected to the first drive shaft, wherein the first movable contact piece is positioned above the first main coil and the first auxiliary coil is positioned below the first movable iron core.

5. When the auxiliary coil generates a magnetic field in a direction that strengthens the magnetic field of the magnetic material, the attractive force between the magnetic material and the auxiliary coil is greater than the attractive force by the first main coil, as described in claim 1.

6. A system comprising: an electromagnetic relay according to claim 1; and a controller for controlling the auxiliary coil, wherein the controller controls the auxiliary coil to generate a magnetic field in a direction that strengthens the magnetic field of the magnetic material when the first movable contact piece is in the first position.

7. A system comprising: an electromagnetic relay according to claim 1; and a controller for controlling the auxiliary coil, wherein the controller controls the auxiliary coil such that when moving the first movable contact piece from a first position to a second position, it generates a magnetic field in a direction that weakens the magnetic field of the magnetic material.

8. A system comprising: an electromagnetic relay according to claim 1; and a controller for controlling the auxiliary coil, wherein the controller controls the auxiliary coil such that when the first movable contact piece is moved from the second position to the first position, a magnetic field is generated in a direction that strengthens the magnetic field of the magnetic material.

9. A system comprising: an electromagnetic relay according to claim 1; and a controller for controlling the auxiliary coil, wherein the electromagnetic relay further comprises: a first main spool around which the first main coil is wound; a first drive shaft connected to the first movable contact piece and extending through the first main spool; a first fixed iron core disposed within the first main spool; and a first movable iron core disposed within the first main spool and connected to the first drive shaft, wherein the first movable iron core comes into contact with the first fixed iron core as the first movable contact piece moves to the second position; and the controller controls the auxiliary coil to generate a magnetic field in a direction that weakens the magnetic field of the magnetic material before the first movable iron core comes into contact with the first fixed iron core.

10. An electromagnetic relay according to claim 1, further comprising: a second fixed contact; a second movable contact facing the second fixed contact, which is movable between a third position and a fourth position, wherein the second movable contact contacts the second fixed contact at one of the third and fourth positions and separates from the second fixed contact at the other of the third and fourth positions; and a second main coil which, when energized, moves the second movable contact from the third position to the fourth position, wherein the magnetic material is disposed between the first main coil and the second main coil, attracting the first movable contact toward the first position and attracting the second movable contact toward the third position; and the auxiliary coil is disposed between the first main coil and the second main coil.

11. The electromagnetic relay according to claim 10, further comprising: a first main spool around which the first main coil is wound; a first drive shaft connected to the first movable contact piece and extending through the first main spool; a first movable iron core disposed within the first main spool and connected to the first drive shaft; a second main spool disposed below the first main spool around which the second main coil is wound; a second drive shaft connected to the second movable contact piece and extending through the second main spool; and a second movable iron core disposed within the second main spool and connected to the second drive shaft, wherein the first movable contact piece is disposed above the first main coil, the second movable contact piece is disposed below the second main coil, and the magnetic material is disposed between the first movable iron core and the second movable iron core.

12. When the auxiliary coil generates a magnetic field in a direction that strengthens the magnetic field of the magnetic material, the attractive force between the magnetic material and the auxiliary coil is greater than the attractive force by the first main coil, and when the auxiliary coil generates a magnetic field in a direction that strengthens the magnetic field of the magnetic material, the attractive force between the magnetic material and the auxiliary coil is greater than the attractive force by the second main coil, the electromagnetic relay according to claim 10.

13. A system comprising: an electromagnetic relay according to claim 10; and a controller for controlling the auxiliary coil, wherein the controller controls the auxiliary coil to generate a magnetic field in a direction that strengthens the magnetic field of the magnetic material when the first movable contact piece is in the first position and the second movable contact piece is in the third position.

14. A system comprising: an electromagnetic relay according to claim 10; and a controller for controlling the auxiliary coil, wherein the controller controls the auxiliary coil to generate a magnetic field in a direction that weakens the magnetic field of the magnetic material when moving the first movable contact piece from a first position to a second position; and controls the auxiliary coil to generate a magnetic field in a direction that weakens the magnetic field of the magnetic material when moving the second movable contact piece from a third position to a fourth position.

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