Electromagnetic relay

Abstract

To obtain a sufficiently large magnetic flux at a contact point while suppressing an increase in size or cost of an electromagnetic relay.SOLUTION: An electromagnetic relay includes a fixed terminal, a fixed contact, a movable contact, a movable piece, and a first magnet. The fixed terminal has a plate-like shape. The fixed contact is provided on the fixed terminal. The movable contact is arranged opposite the fixed contact. The movable piece is provided with the movable contact. The movable piece is movable between a closed position and an open position. When the movable piece is in the closed position, the movable contact comes into contact with the fixed contact. When the movable piece is in the open position, the movable contact is separated from the fixed contact. The first magnet is arranged to penetrate the fixed terminal in the plate thickness direction of the fixed terminal.SELECTED DRAWING: Figure 3

Description

[Technical Field]

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

[0002] Some electromagnetic relays are equipped with a magnet to quickly extinguish an arc that occurs when the contacts are broken. For example, in the electromagnetic relay of Patent Document 1, a magnet is placed below the fixed terminal. The magnetic field of the magnet causes a Lorentz force to act on the arc, causing it to move. This allows the arc to be quickly extinguished. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2023-151054 Summary of the Invention [Problem to be solved by the invention]

[0004] In order to extinguish an arc more quickly, it is desirable to obtain a sufficiently large magnetic flux at the contacts. However, in the above-mentioned electromagnetic relay, the magnet is positioned to avoid the fixed terminal, so the distance between the magnet and the contacts is large. Therefore, to obtain a sufficiently large magnetic flux at the contacts, a larger magnet is required. In this case, the electromagnetic relay becomes larger. Alternatively, to obtain a sufficiently large magnetic flux at the contacts, a magnet with a stronger magnetic force is required. In this case, the cost of the electromagnetic relay increases. An object of the present invention is to obtain a sufficiently large magnetic flux at the contacts while suppressing an increase in the size or cost of the electromagnetic relay. [Means for solving the problem]

[0005] An electromagnetic relay according to one aspect of the present invention comprises a fixed terminal, a fixed contact, a movable contact, a movable piece, and a first magnet. The fixed terminal has a plate-like shape. The fixed contact is provided on the fixed terminal. The movable contact is arranged opposite the fixed contact. The movable piece is provided with a movable contact. The movable piece is movable between a closed position and an open position. When the movable piece is in the closed position, the movable contact comes into contact with the fixed contact. When the movable piece is in the open position, the movable contact is separated from the fixed contact. The first magnet is arranged to penetrate the fixed terminal in the plate thickness direction of the fixed terminal.

[0006] In the electromagnetic relay according to this aspect, the first magnet is disposed so as to penetrate the fixed terminal in the plate thickness direction of the fixed terminal. Therefore, the first magnet can be disposed near the contact point. This allows a sufficiently large magnetic flux to be obtained at the contact point while suppressing an increase in the size or cost of the electromagnetic relay.

[0007] The electromagnetic relay may further include a magnet case. The magnet case may be disposed around the first magnet and provide electrical insulation between the first magnet and the fixed terminal. In this case, the magnet case ensures electrical insulation between the first magnet and the fixed terminal.

[0008] The electromagnetic relay may further include a yoke disposed to the side of the magnet. The magnet case may include an opening. The first magnet may be in contact with the yoke through the opening. In this case, the first magnet being in contact with the yoke provides a sufficiently large magnetic flux at the contact point.

[0009] The fixed terminal may include a contact support portion and a magnet support portion. The contact support portion may be provided with a fixed contact. The magnet support portion may be wider than the contact support portion. The first magnet may be disposed to penetrate the magnet support portion in the plate thickness direction. In this case, the wide magnet support portion compensates for the reduction in the cross-sectional area of ​​the fixed terminal caused by the first magnet being disposed to penetrate the fixed terminal. This prevents an increase in electrical resistance due to the reduction in the cross-sectional area of ​​the fixed terminal.

[0010] The fixed terminal may include a hole extending through the fixed terminal in a thickness direction, and the first magnet may be disposed through the hole, whereby the hole allows the first magnet to be disposed through the fixed terminal.

[0011] The fixed terminal may include a notch extending through the fixed terminal in a thickness direction, and the first magnet may be disposed through the notch, in which case the notch allows the first magnet to be disposed through the fixed terminal.

[0012] The movable piece may be movable in the vertical direction between the closed position and the open position. At least a portion of the magnet may be located between the movable contact and the fixed contact in the open position in the vertical direction. In this case, a sufficient amount of magnetic flux is ensured between the movable contact and the fixed contact in the open position.

[0013] In the vertical direction, the center of the first magnet may be located between the movable contact and the fixed contact in the open position. In this case, a sufficiently large magnetic flux is ensured between the movable contact and the fixed contact in the open position. In the vertical direction, the center of the first magnet may be located at the center between the movable contact and the fixed contact in the open position. In this case, a sufficiently large magnetic flux is ensured between the movable contact and the fixed contact in the open position.

[0014] The electromagnetic relay may further include a second magnet. The second magnet may be arranged relative to the first magnet in the magnetic flux direction of the first magnet. The first magnet and the second magnet may be arranged symmetrically with respect to the fixed contact in the magnetic flux direction. In this case, the first magnet and the second magnet ensure a sufficiently large magnetic flux at the contact. Furthermore, by arranging the first magnet so that it passes through the fixed terminal, the first magnet and the second magnet can be arranged symmetrically in positions close to the contact. [Effects of the Invention]

[0015] According to the present invention, a sufficiently large magnetic flux can be obtained at the contacts while suppressing an increase in the size or cost of the electromagnetic relay. [Brief explanation of the drawings]

[0016] [Figure 1] FIG. [Figure 2] FIG. [Figure 3] FIG. 2 is a perspective view of a first fixed terminal and a second fixed terminal. [Figure 4] FIG. 3 is an enlarged cross-sectional view of a first fixed terminal and a second fixed terminal. [Figure 5] FIG. 2 is a perspective view of a first fixed terminal. [Figure 6] FIG. 4 is a top view of the first fixed terminal. [Figure 7] FIG. 10 is a top view showing a first fixed terminal, a first magnet, and a first magnet case according to a first modified example. [Figure 8] FIG. 10 is a top view showing a contact device according to a second modified example. DETAILED DESCRIPTION OF THE INVENTION

[0017] An electromagnetic relay according to an embodiment of the present invention will be described below with reference to the drawings. Fig. 1 is a cross-sectional view of an electromagnetic relay 1. As shown in Fig. 1, the electromagnetic relay 1 includes a housing 2, a contact device 3, and a drive device 4. The housing 2 accommodates the contact device 3. The contact device 3 includes a first fixed terminal 6, a second fixed terminal 7, a movable piece 8, a movable mechanism 9, a first fixed contact 10, a second fixed contact 11, a first movable contact 12, a second movable contact 13, and a contact case 20.

[0018] In the following description, the direction in which the first fixed contact 10 and the first movable contact 12 face each other is defined as the up-down direction. The direction perpendicular to the up-down direction is defined as the lateral direction. The lateral direction includes the left-right direction and the front-rear direction. The longitudinal direction of the movable piece 8 is defined as the left-right direction. The direction perpendicular to the up-down direction and the left-right direction is defined as the front-rear direction.

[0019] The direction from the movable contacts 12, 13 toward the fixed contacts 10, 11 is defined as the upward direction. The direction from the fixed contacts 10, 11 toward the movable contacts 12, 13 is defined as the downward direction. The direction from the first fixed contact 10 toward the second fixed contact 11 is defined as the right direction. The direction from the second fixed contact 11 toward the first fixed contact 10 is defined as the left direction.

[0020] The first fixed terminal 6, the second fixed terminal 7, the movable piece 8, the first fixed contact 10, the second fixed contact 11, the first movable contact 12, and the second movable contact 13 are made of a conductive material. For example, the first fixed terminal 6, the second fixed terminal 7, and the movable piece 8 are made of a metal material known as a terminal material, such as a copper-based metal. However, the first fixed terminal 6, the second fixed terminal 7, and the movable piece 8 may be made of a different material. The first fixed contact 10, the second fixed contact 11, the first movable contact 12, and the second movable contact 13 are made of a metal material known as a contact material, such as a copper-based metal or a silver-based metal.

[0021] The first fixed terminal 6 and the second fixed terminal 7 are arranged apart from each other in the left-right direction. The first fixed terminal 6 and the second fixed terminal 7 each have a plate-like shape. The first fixed terminal 6 and the second fixed terminal 7 protrude from inside the housing 2 to the outside of the housing 2. A first fixed contact 10 is connected to the first fixed terminal 6. A second fixed contact 11 is connected to the second fixed terminal 7. The first fixed contact 10 and the second fixed contact 11 are arranged in a contact case 20.

[0022] The first fixed terminal 6 includes a first contact support portion 14 and a first external terminal portion 15. The first fixed contact 10 is connected to the first contact support portion 14. The first external terminal portion 15 protrudes laterally from the housing 2. The second fixed terminal 7 includes a second contact support portion 17 and a second external terminal portion 18. The second fixed contact 11 is connected to the second contact support portion 17. The second external terminal portion 18 protrudes laterally from the housing 2. The second external terminal portion 18 protrudes from the housing 2 on the side opposite to the first external terminal portion 15.

[0023] The movable piece 8, the first movable contact 12, and the second movable contact 13 are arranged in a contact case 20. The first movable contact 12 and the second movable contact 13 are connected to the movable piece 8. The first movable contact 12 faces the first fixed contact 10. The second movable contact 13 faces the second fixed contact 11. The first movable contact 12 is arranged spaced apart from the second movable contact 13 in the left-right direction.

[0024] The movable piece 8 is movable in the vertical direction. The movable piece 8 is movable between an open position shown in Fig. 1 and a closed position shown in Fig. 2. As shown in Fig. 1, when the movable piece 8 is in the open position, the movable contacts 12 and 13 are separated from the fixed contacts 10 and 11. As shown in Fig. 2, when the movable piece 8 is in the closed position, the movable contacts 12 and 13 are in contact with the fixed contacts 10 and 11.

[0025] The movable mechanism 9 supports the movable piece 8. The movable mechanism 9 includes a drive shaft 21 and a contact spring 22. The drive shaft 21 is connected to the movable piece 8. The drive shaft 21 extends in the vertical direction and penetrates the movable piece 8 in the vertical direction. The drive shaft 21 is provided so as to be movable in the vertical direction. The contact spring 22 biases the movable piece 8 in the contact direction (upward).

[0026] As shown in Figures 1 and 2, the drive unit 4 moves the drive shaft 21 in the up and down direction. The drive unit 4 includes a coil 23, a spool 24, a movable iron core 25, a fixed iron core 26, a yoke 27, and a return spring 28. The drive unit 4 uses electromagnetic force to move the movable piece 8 between the open position and the closed position via the moving mechanism 9. The coil 23 is wound around the spool 24. The movable iron core 25 and the fixed iron core 26 are disposed within the spool 24. The movable iron core 25 is connected to the drive shaft 21. The movable iron core 25 is movable in the up and down direction. The fixed iron core 26 is disposed opposite the movable iron core 25. The return spring 28 biases the movable iron core 25 in the opening direction (downward).

[0027] In the electromagnetic relay 1, when the coil 23 is energized, the magnetic force of the coil 23 attracts the movable core 25 to the fixed core 26. As a result, the movable core 25 and the drive shaft 21 move in the contact direction (upward) against the biasing force of the return spring 28. As a result, the movable piece 8 moves to the closed position shown in Fig. 2, and the movable contacts 12 and 13 come into contact with the fixed contacts 10 and 11. After the movable contacts 12 and 13 come into contact with the fixed contacts 10 and 11, the drive shaft 21 moves further in the contact direction, compressing the contact spring 22.

[0028] When the current to the coil 23 is turned off, the movable iron core 25 and the drive shaft 21 move in the opening direction (downward) due to the biasing force of the return spring 28. As a result, the movable piece 8 moves to the open position shown in FIG. 1, and the movable contacts 12 and 13 move away from the fixed contacts 10 and 11.

[0029] The electromagnetic relay 1 according to this embodiment is equipped with a magnet for extinguishing an arc that occurs between the contacts. The structure for holding the magnet in the electromagnetic relay 1 will be described below. FIG. 3 is a perspective view of the first fixed terminal 6 and the second fixed terminal 7. FIG. 4 is an enlarged cross-sectional view of the first fixed terminal 6 and the second fixed terminal 7. FIG. 5 is a perspective view of the first fixed terminal 6. FIG. 6 is a top view of the first fixed terminal 6.

[0030] As shown in Figures 3 and 4, the electromagnetic relay 1 includes a first magnet 31, a first magnet case 32, a second magnet 33, a second magnet case 34, and a yoke 35. The first magnet 31 is arranged so as to penetrate the first fixed terminal 6 in the thickness direction of the first fixed terminal 6. In the electromagnetic relay 1 according to this embodiment, the thickness direction of the first fixed terminal 6 is the vertical direction of the electromagnetic relay 1. The first magnet 31 has a prismatic shape. The first magnet 31 has a quadrangular shape when viewed from above. The first magnet 31 has a square shape when viewed from above. However, the first magnet 31 may have a rectangular shape when viewed from above.

[0031] As shown in FIG. 4 , the first fixed terminal 6 includes a first magnet support portion 36. The first magnet support portion 36 is located between the first contact support portion 14 and the first external terminal portion 15 in the left-right direction. The first magnet support portion 36 is wider than the first contact support portion 14 in the front-rear direction. The first magnet support portion 36 is wider than the first external terminal portion 15 in the front-rear direction. The first magnet support portion 36 includes a first hole 37. The first hole 37 extends through the first magnet support portion 36 in the up-down direction. The first magnet 31 is disposed through the first hole 37. At least a portion of the first magnet 31 is disposed within the first hole 37. The first magnet 31 is disposed so as to penetrate the first magnet support portion 36 in the up-down direction.

[0032] The first magnet case 32 is disposed around the first magnet 31. The first magnet case 32 covers the first magnet 31 from the left, right, front, rear, and bottom. The first magnet case 32 is made of an insulating material such as resin or ceramic. The first magnet case 32 may be provided integrally with the contact case 20. Alternatively, the first magnet case 32 may be separate from the contact case 20.

[0033] The first magnet case 32 is arranged through the first hole 37. The first magnet case 32 passes through the first hole 37 and protrudes above the first fixed terminal 6. The first magnet case 32 passes through the first hole 37 and protrudes below the first fixed terminal 6. The first magnet case 32 is arranged between the first magnet 31 and the first fixed terminal 6. The first magnet case 32 electrically insulates the first magnet 31 from the first fixed terminal 6.

[0034] The first magnet case 32 includes a case body 38 and a terminal support portion 39. The case body 38 has a box-like shape. The case body 38 is disposed through the first hole 37. The first magnet 31 is disposed within the case body 38. The case body 38 includes an upper opening 41. The upper opening 41 opens upward. The upper opening 41 is located above the first fixed terminal 6.

[0035] The case body 38 includes a side opening 42. The side opening 42 opens to the side. Specifically, the side opening 42 opens to the left. The side opening 42 is located below the first fixed terminal 6. A portion of the first magnet 31 passes through the side opening 42 and is exposed to the outside of the first magnet case 32. The first magnet 31 passes through the side opening 42 and comes into contact with the yoke 35. The yoke 35 is made of a magnetic material.

[0036] Specifically, the yoke 35 is disposed so as to surround the sides of the first fixed contact 10, the first movable contact 12, the second fixed contact 11, and the second movable contact 13. As shown in FIG. 3 , the yoke 35 includes a front yoke portion 43, a rear yoke portion 44, a left yoke portion 45, and a right yoke portion 46. The front yoke portion 43 is disposed in front of the first fixed contact 10, the first movable contact 12, the second fixed contact 11, and the second movable contact 13. The rear yoke portion 44 is disposed behind the first fixed contact 10, the first movable contact 12, the second fixed contact 11, and the second movable contact 13. The left yoke portion 45 is disposed to the left of the first fixed contact 10 and the first movable contact 12. The right yoke portion 46 is disposed to the right of the second fixed contact 11 and the second movable contact 13. As shown in FIG. 4, the first magnet 31 passes through the side opening 42 and contacts the left yoke portion 45.

[0037] Terminal support portion 39 protrudes laterally from case body 38. More specifically, terminal support portion 39 protrudes leftward from case body 38. Terminal support portion 39 is disposed below first fixed terminal 6 and is in contact with the lower surface of first fixed terminal 6. Terminal support portion 39 supports first fixed terminal 6 from below.

[0038] 4, at least a portion of the first magnet 31 is located between the first movable contact 12 and the first fixed contact 10 in the open position in the vertical direction. The center of the first magnet 31 is located at the center between the first movable contact 12 and the first fixed contact 10 in the open position in the vertical direction. However, the center of the first magnet 31 may be positioned offset from the center between the first movable contact 12 and the first fixed contact 10 in the open position in the vertical direction. In FIG. 4, the dashed dotted line L1 indicates the center position of the first magnet 31 and the second magnet 33.

[0039] The second magnet 33 is arranged to pass through the second fixed terminal 7 in the vertical direction. The second fixed terminal 7 includes a second magnet support portion 51. The second magnet support portion 51 includes a second hole 52. The second hole 52 extends through the second magnet support portion 51 in the vertical direction. The second magnet 33 is arranged to pass through the second hole 52. The second magnet case 34 is arranged around the second magnet 33. The second magnet case 34 is arranged to pass through the second hole 52.

[0040] The configuration of the second magnet 33 and the second magnet case 34 is similar to the configuration of the first magnet 31 and the first magnet case 32 except that they are symmetrical, so a detailed description will be omitted. As shown in Fig. 4, the right yoke portion 46 of the yoke 35 passes through a side opening 53 of the second magnet case 34 and comes into contact with the second magnet 33. The yoke 35 surrounds the first magnet 31 and the second magnet 33 from the left and right sides.

[0041] In the electromagnetic relay 1 according to the present embodiment described above, the first magnet 31 is disposed so as to penetrate the first fixed terminal 6 in the thickness direction of the first fixed terminal 6. Therefore, the first magnet 31 can be disposed near the first fixed contact 10 and the first movable contact 12. This allows a sufficiently large magnetic flux to be obtained at the first fixed contact 10 and the first movable contact 12 while suppressing an increase in size or cost of the electromagnetic relay 1. Furthermore, the second magnet 33 also provides the same effect as the first magnet 31.

[0042] 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 gist of the invention.

[0043] The structure of the drive device 4 is not limited to that of the above embodiment and may be modified. For example, the separation direction and contact direction may be opposite to those of the above embodiment. The structure of the contact device 3 is not limited to that of the above embodiment and may be modified. For example, the first fixed contact 10 may be separate from the first fixed terminal 6 or may be integrated with it. The second fixed contact 11 may be separate from the second fixed terminal 7 or may be integrated with it. The first movable contact 12 and the second movable contact 13 may be separate from the movable piece 8 or may be integrated with it.

[0044] The first fixed terminal 6 and the second fixed terminal 7 may protrude from the housing 2 in the front-rear direction, not just the left-right direction. The first fixed terminal 6 and the second fixed terminal 7 may not be linear, but may be bent in an L-shape or a U-shape. The first fixed terminal 6 may be positioned by the first magnet case 32 or the first magnet 31. The second fixed terminal 7 may be positioned by the second magnet case 34 or the second magnet 33.

[0045] The magnetic poles of the first magnet 31 may be oriented such that, for example, the right end of the first magnet 31 is a north pole and the left end is a south pole. Alternatively, the magnetic poles of the first magnet 31 may be oriented such that the left end of the first magnet 31 is a north pole and the right end is a south pole. Alternatively, the magnetic poles of the first magnet 31 may be oriented such that the front end of the first magnet 31 is a north pole and the rear end is a south pole. Alternatively, the magnetic poles of the first magnet 31 may be oriented such that the rear end of the first magnet 31 is a north pole and the front end is a south pole. The magnetic poles of the second magnet 33 are oriented in the same way as the magnetic poles of the first magnet 31.

[0046] 7 is a top view showing the first fixed terminal 6, first magnet 31, and first magnet case 32 according to a first modified example. As shown in FIG. 7, the first fixed terminal 6 may include a first cutout 47 instead of the first hole 37. The first cutout 47 may extend vertically through the first fixed terminal 6. The first magnet 31 may be disposed through the first cutout 47. Although not shown, the second magnet 33 may also be disposed through a cutout provided in the second fixed terminal 7, similar to the first magnet 31.

[0047] Fig. 8 is a top view showing a contact device 3 according to a second modification. As shown in Fig. 8, the first magnet 31 may be arranged so as to pass through the first fixed terminal 6 and the second fixed terminal 7 in the up-down direction. The first fixed terminal 6 may include a first notch 47. The second fixed terminal 7 may include a second notch 48. The first magnet 31 may be arranged so as to pass through the first notch 47 and the second notch 48 in the up-down direction.

[0048] The second magnet 33 may be disposed relative to the first magnet 31 in the magnetic flux direction of the first magnet 31. In Fig. 8, arrows A1 and A2 indicate the magnetic flux direction of the first magnet 31. The first magnet 31 and the second magnet 33 may be disposed symmetrically with respect to the fixed contacts 10 and 11 in the magnetic flux direction. [Industrial Applicability]

[0049] According to the present invention, a sufficiently large magnetic flux can be obtained at the contacts while suppressing an increase in the size or cost of the electromagnetic relay. [Explanation of symbols]

[0050] 1: electromagnetic relay, 6: first fixed terminal, 8: movable piece, 10: first fixed contact, 12: first movable contact, 14: first contact support portion, 31: first magnet, 32: first magnet case, 33: second magnet, 35: yoke, 36: first magnet support portion, 37: first hole, 42: side opening, 47: first notch

Claims

1. a fixed terminal having a plate-like shape; a fixed contact provided on the fixed terminal; a movable contact arranged opposite the fixed contact; a movable piece provided with the movable contact and movable between a closed position where the movable contact contacts the fixed contact and an open position where the movable contact is separated from the fixed contact; a first magnet disposed to penetrate the fixed terminal in a thickness direction of the fixed terminal; An electromagnetic relay comprising:

2. a magnet case disposed around the first magnet and electrically insulating the first magnet from the fixed terminal; 2. The electromagnetic relay according to claim 1.

3. a yoke disposed on the side of the magnet; the magnet case includes an opening; The first magnet passes through the opening and contacts the yoke.

3. The electromagnetic relay according to claim 2.

4. the fixed terminal includes a contact support portion on which the fixed contact is provided, and a magnet support portion that is wider than the contact support portion, The first magnet is disposed to penetrate the magnet support portion in the plate thickness direction.

2. The electromagnetic relay according to claim 1.

5. the fixed terminal includes a hole extending through the fixed terminal in the plate thickness direction; The first magnet is disposed through the hole.

2. The electromagnetic relay according to claim 1.

6. the fixed terminal includes a notch extending through the fixed terminal in the plate thickness direction, The first magnet is disposed through the notch.

2. The electromagnetic relay according to claim 1.

7. the movable piece is movable in a vertical direction between the closed position and the open position, At least a portion of the magnet is located between the movable contact and the fixed contact in the up-down direction in the open position.

2. The electromagnetic relay according to claim 1.

8. In the vertical direction, the center of the first magnet is located between the movable contact and the fixed contact in the open position.

8. An electromagnetic relay according to claim 7.

9. In the vertical direction, the center of the first magnet is located at the center between the movable contact and the fixed contact in the open position.

8. An electromagnetic relay according to claim 7.

10. a second magnet disposed in a magnetic flux direction of the first magnet relative to the first magnet; The first magnet and the second magnet are arranged symmetrically with respect to the fixed contact in the magnetic flux direction.

2. The electromagnetic relay according to claim 1.

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