Electromagnetic relay

Abstract

This electromagnetic relay includes a fixed terminal, a fixed contact, a movable contact, a movable piece, a coil, a coil terminal, and solder. The fixed contact is connected to the fixed terminal. The movable contact is disposed facing the fixed contact. The movable contact is connected to the movable piece. The movable piece is movable between a closed position and an open position. When the movable piece is at the closed position, the movable contact is in contact with the fixed contact. When the movable piece is at the open position, the movable contact is separated from the fixed contact. The coil generates an electromagnetic force for moving the movable piece between the open position and the closed position. The coil includes a lead-out wire. The coil terminal includes a binding part. The lead-out wire is wound around the binding part. The binding part includes a recessed shape. The solder is attached to the binding part in the recessed shape, thereby fixing the lead-out wire to the binding part.

Description

electromagnetic relay

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

[0002] The electromagnetic relay includes a coil and a coil terminal for supplying power to the coil. For example, in the electromagnetic relay of Patent Document 1, the lead wire of the coil is wound around a entanglement portion of the coil terminal and fixed to the entanglement portion by soldering.

[0003] JP 2010-10055 A

[0004] As described above, when a coil lead wire is soldered to a coil terminal, depending on the shape of the coil terminal, heat may not be transferred easily to the coil terminal, resulting in insufficient soldering. Making the coil terminal thinner improves heat transfer, but reduces the strength of the coil terminal against the winding of the lead wire. The object of the present invention is to improve the quality of soldering to the winding portion of the coil lead wire while maintaining the strength of the winding portion of the coil terminal.

[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, a coil, a coil terminal, and solder. The fixed contact is connected to the fixed terminal. The movable contact is arranged opposite the fixed contact. The movable contact is connected to the movable piece. 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 is in contact with the fixed contact. When the movable piece is in the open position, the movable contact is separated from the fixed contact. The coil generates an electromagnetic force that moves the movable piece between the open position and the closed position. The coil includes a lead wire. The coil terminal includes a entanglement portion. The lead wire is wound around the entanglement portion. The entanglement portion includes a concave shape. The solder is attached to the entanglement portion in the concave shape to secure the lead wire to the entanglement portion.

[0006] In the electromagnetic relay according to this aspect, the concave shape of the entanglement portion reduces the volume of the entanglement portion while maintaining the thickness of the entanglement portion. This allows heat to be more easily transferred to the entanglement portion, improving the quality of soldering of the coil lead wires to the entanglement portion. Furthermore, the thickness of the entanglement portion is maintained, thereby maintaining the strength of the entanglement portion.

[0007] The entanglement portion may have a plate-like shape. The recessed shape may be recessed from the surface of the entanglement portion in the plate thickness direction. In this case, the recessed shape can be provided over a wide range of the entanglement portion. The entanglement portion may have a plate-like shape. The entanglement portion may include an end face extending in the plate thickness direction. The recessed shape may be provided on the end face. The recessed shape may include multiple depressions. In this case, the strength of the entanglement portion is improved compared to when one large depression is provided.

[0008] The recessed shape may be polygonal. The recessed shape may be circular. The recessed shape may be groove-like. The recessed shape may penetrate the entangled portion. These recessed shapes improve the heat transfer in the entangled portion and maintain the strength of the entangled portion.

[0009] According to the present invention, the quality of soldering of the coil lead wire to the twisted portion is improved while maintaining the strength of the twisted portion of the coil terminal.

[0010] 8. A perspective view of an electromagnetic relay according to an embodiment. A cross-sectional view of an electromagnetic relay. A cross-sectional view of an electromagnetic relay. A front view of an electromagnetic relay with the cover omitted. A cross-sectional view taken along V-V in FIG. 4. A perspective view of a first coil terminal. An enlarged perspective view of the first coil terminal. An enlarged front view of the first coil terminal. A cross-sectional view taken along IX-IX in FIG. 8. An enlarged front view of a first coil terminal showing a first binding portion around which a first lead wire is wound and fixed by solder. An enlarged front view of a first coil terminal according to a first modified example. An enlarged front view of a first coil terminal according to a second modified example. An enlarged front view of a first coil terminal according to a third modified example. An enlarged front view of a first coil terminal according to a fourth modified example. A cross-sectional view of a first coil terminal according to a fifth modified example.

[0011] An electromagnetic relay according to an embodiment of the present invention will now be described with reference to the drawings. Fig. 1 is a perspective view of an electromagnetic relay 1 according to an embodiment. Figs. 2 and 3 are cross-sectional views of the electromagnetic relay 1. As shown in Figs. 1 to 3, the electromagnetic relay 1 includes a housing 2, a contact device 3, and a drive device 4.

[0012] The housing 2 includes a case 2A and a cover 2B. The cover 2B is attached to the case 2A. A contact device 3 and a drive device 4 are housed within the housing 2. 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, and a second movable contact 13.

[0013] 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. The direction from the movable contacts 12, 13 toward the fixed contacts 10, 11 is defined as the contact direction (Z1). The direction from the fixed contacts 10, 11 toward the movable contacts 12, 13 is defined as the separation direction (Z2).

[0014] 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 metallic 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 metallic material known as a contact material, such as a copper-based metal or a silver-based metal.

[0015] 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 inside the housing 2.

[0016] The movable piece 8, the first movable contact 12, and the second movable contact 13 are arranged inside the housing 2. 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.

[0017] The movable piece 8 is movable in the vertical direction. The movable piece 8 is movable between an open position shown in Fig. 2 and a closed position shown in Fig. 3. As shown in Fig. 2, 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. 3, 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.

[0018] 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 (Z1).

[0019] As shown in Figures 2 and 3, 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 (Z2).

[0020] 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 (Z1) against the biasing force of the return spring 28. As a result, the movable piece 8 moves to the closed position shown in Figure 3, 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 (Z1), compressing the contact spring 22.

[0021] 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 (Z2) due to the biasing force of the return spring 28. As a result, the movable piece 8 moves to the open position shown in Figure 2, and the movable contacts 12 and 13 move away from the fixed contacts 10 and 11.

[0022] Fig. 4 is a front view of the electromagnetic relay 1 without the cover 2B. Fig. 5 is a cross-sectional view taken along line VV in Fig. 4. As shown in Figs. 4 and 5, the electromagnetic relay 1 includes a connector housing 30, a first coil terminal 31, and a second coil terminal 32. The connector housing 30 is attached to the outer surface of the case 2A.

[0023] The first coil terminal 31 and the second coil terminal 32 are formed of a conductive material. For example, the first coil terminal 31 and the second coil terminal 32 are made of a metallic material known as a terminal material, such as a copper-based metal. However, the first coil terminal 31 and the second coil terminal 32 may be made of a different material. A portion of the first coil terminal 31 and the second coil terminal 32 is disposed within the connector housing 30. The first coil terminal 31 and the second coil terminal 32 are connected to the coil 23. A current flows through the coil 23 via the first coil terminal 31 and the second coil terminal 32.

[0024] In detail, the coil 23 includes a coil body 33, a first lead wire 34, and a second lead wire 35. The coil body 33 is wound around the spool 24. The first lead wire 34 extends from the coil body 33 toward the first coil terminal 31. The first lead wire 34 is connected to the first coil terminal 31. The second lead wire 35 extends from the coil body 33 toward the second coil terminal 32. The second lead wire 35 is connected to the second coil terminal 32.

[0025] The spool 24 includes a cylindrical portion 36, a first flange portion 37, a second flange portion 38, and a terminal support portion 39. The coil body 33 is wound around the cylindrical portion 36. The first flange portion 37 and the second flange portion 38 protrude from the cylindrical portion 36 in the outer diameter direction of the spool 24. The cylindrical portion 36 is located between the first flange portion 37 and the second flange portion 38. The terminal support portion 39 is connected to the first flange portion 37. The terminal support portion 39 supports the first coil terminal 31 and the second coil terminal 32.

[0026] 6 is a perspective view of the first coil terminal 31. As shown in FIG. 6, the first coil terminal 31 includes a first terminal body 41, a first connecting portion 42, and a first entanglement portion 43. The first terminal body 41 protrudes from inside the housing 2 to the outside of the housing 2. A portion of the first terminal body 41 is disposed within the connector housing 30. The first connecting portion 42 is connected to the first terminal body 41 and the first entanglement portion 43. The first connecting portion 42 connects the first terminal body 41 and the first entanglement portion 43. The first coil terminal 31 has a bent shape between the first terminal body 41 and the first connecting portion 42.

[0027] The first lead wire 34 is wound around the first entanglement portion 43. The first coil terminal 31 has a bent shape between the first connecting portion 42 and the first entanglement portion 43. The first entanglement portion 43 has a plate-like shape. FIG. 7 is an enlarged perspective view of the first coil terminal 31. FIG. 8 is an enlarged front view of the first coil terminal 31. FIG. 9 is a cross-sectional view taken along line IX-IX in FIG. 8.

[0028] 7 to 9 , the first interlocking portion 43 includes a first surface 44 and a second surface 45. The first surface 44 and the second surface 45 are planes perpendicular to the thickness direction T1 of the first interlocking portion 43. The first surface 44 is disposed facing the first terminal body 41. The second surface 45 is located on the opposite side to the first surface 44 in the thickness direction T1.

[0029] The first entanglement portion 43 includes an upper end surface 46, a lower end surface 47, and a tip surface 48. The upper end surface 46, the lower end surface 47, and the tip surface 48 extend in the plate thickness direction T1. The first entanglement portion 43 includes a first locking portion 46A and a second locking portion 47A. The first locking portion 46A is recessed downward from the upper end surface 46. The second locking portion 47A is recessed upward from the lower end surface 47. The first locking portion 46A and the second locking portion 47A lock the first lead wire 34 wound around the first entanglement portion 43.

[0030] The first interlocking portion 43 includes a recessed shape 49. The recessed shape 49 includes a plurality of recesses 49A. Note that in the drawings, only some of the plurality of recesses 49A are denoted by reference numerals 49A, and the reference numerals for the other recesses 49A are omitted. The plurality of recesses 49A are provided on the second surface 45. The plurality of recesses 49A are provided on the second surface 45 in a range between the first locking portion 46A and the tip surface 48. The plurality of recesses 49A are recessed from the second surface 45 in the plate thickness direction T1 of the interlocking portion.

[0031] 10 is an enlarged front view of the first coil terminal 31, showing the first entanglement portion 43 around which the first lead wire 34 is wound and secured by solder 50. As shown in FIG. 10 , the solder 50 is attached to the first entanglement portion 43 at the recessed portion 49, thereby securing the first lead wire 34 to the first entanglement portion 43. Specifically, the first lead wire 34 is wound around the first entanglement portion 43 in the range between the first locking portion 46A and the second locking portion 47A. The solder 50 is attached to the first entanglement portion 43 in the range where at least a plurality of recesses 49A are provided in the first entanglement portion 43. Therefore, the solder 50 is attached to the first entanglement portion 43 so as to cover at least a portion of the plurality of recesses 49A and at least a portion of the first lead wire 34.

[0032] 5, the second coil terminal 32 has a shape symmetrical to the first coil terminal 31. The second coil terminal 32 includes a second terminal body 51, a second connecting portion 52, and a second entanglement portion 53. The second terminal body 51, the second connecting portion 52, and the second entanglement portion 53 have shapes similar to those of the first terminal body 41, the first connecting portion 42, and the first entanglement portion 43, respectively, and therefore detailed description thereof will be omitted.

[0033] In the electromagnetic relay 1 according to the present embodiment described above, the first entanglement portion 43 includes the recessed shape 49, thereby reducing the volume of the first entanglement portion 43 while maintaining the thickness of the first entanglement portion 43. This facilitates heat transfer to the first entanglement portion 43, improving the quality of the soldering 50 of the first lead wire 34 of the coil 23 to the first entanglement portion 43. Furthermore, since the thickness of the first entanglement portion 43 is maintained, the strength of the first entanglement portion 43 is maintained. Note that the second coil terminal 32 also has a shape similar to that of the first coil terminal 31, and the second coil terminal 32 also provides the same effects as the first coil terminal 31.

[0034] 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.

[0035] The configuration of the electromagnetic relay 1 is not limited to that of the above embodiment and may be changed. For example, the electromagnetic relay 1 is not limited to a so-called plunger type electromagnetic relay as in the above embodiment, but may be another type of electromagnetic relay such as a hinge type.

[0036] The first fixed contact 10 may be separate from or integrated with the first fixed terminal 6. The second fixed contact 11 may be separate from or integrated with the second fixed terminal 7. The first movable contact 12 and the second movable contact 13 may be separate from or integrated with the movable piece 8.

[0037] The connector housing 30 may be omitted. The shapes of the first coil terminal 31 and the second coil terminal 32 may be changed. For example, the first coil terminal 31 and the second coil terminal 32 are not limited to being bent, and may have a linear shape.

[0038] The recessed shapes 49 of the first coil terminal 31 and the second coil terminal 32 are not limited to those in the above embodiment and may be modified. For example, the shape of the recess 49A is not limited to a square as in the above embodiment and may be other shapes. The recess 49A may be other polygonal shapes such as a triangle, a pentagon, or a hexagon. Fig. 11 is an enlarged front view of the first coil terminal 31 according to a first modified example. As shown in Fig. 11, the recessed shape 49 may include a circular recess 49B.

[0039] The recessed shape 49 may have a groove-like shape. Fig. 12 is an enlarged front view of a first coil terminal 31 according to a second modified example. As shown in Fig. 12, the recessed shape 49 may include a plurality of groove-like depressions 49C extending parallel to each other. Fig. 13 is an enlarged front view of a first coil terminal 31 according to a third modified example. As shown in Fig. 13, the recessed shape 49 may be formed by a single depression 49D.

[0040] The recessed shape 49 is not limited to being provided on the second surface 45, and may be provided on other portions of the first entangling portion 43. For example, the recessed shape 49 may be provided on any one of the first surface 44, the upper end surface 46, the lower end surface 47, or the tip surface 48. The recessed shape 49 may be provided on more than one of the first surface 44, the upper end surface 46, the lower end surface 47, and the tip surface 48.

[0041] 14 is a front view of a first coil terminal 31 according to a fourth modified example. As shown in FIG. 14, a recess 49E may be provided in the upper end surface 46. A recess 49F may be provided in the lower end surface 47. A recess 49G may be provided in the tip surface 48. Alternatively, two or more of the recesses 49A-49G of the recessed shape 49 described above may be combined and provided in the first entangling portion 43.

[0042] The recessed shape 49 is not limited to the bottomed depression 49A as in the above embodiment. For example, Fig. 15 is a cross-sectional view of a first coil terminal 31 according to a fifth modified example. As shown in Fig. 15, the recessed shape 49 may penetrate the first entanglement portion 43. The second coil terminal 32 may also have a shape similar to that of the first coil terminal 31 according to the above modified example.

[0043] According to the present invention, the quality of soldering of the coil lead wire to the twisted portion is improved while maintaining the strength of the twisted portion of the coil terminal.

[0044] 6: First fixed terminal, 8: Movable piece, 10: Fixed contact, 12: First movable contact, 23: Coil, 31: First coil terminal, 34: First lead wire, 43: First binding portion, 46: Upper end surface, 47: Lower end surface, 48: End surface, 49A: Recess, 50: Solder

Claims

1. An electromagnetic relay comprising: a fixed terminal; a fixed contact connected to the fixed terminal; a movable contact arranged opposite the fixed contact; a movable piece to which the movable contact is connected and movable between a closed position in which the movable contact is in contact with the fixed contact and an open position in which the movable contact is separated from the fixed contact; a coil including a lead wire and generating an electromagnetic force that moves the movable piece between the open position and the closed position; a coil terminal including a entanglement portion around which the lead wire is wound, the entanglement portion having a concave shape; and solder that is attached to the entanglement portion in the concave shape to fix the lead wire to the entanglement portion.

2. An electromagnetic relay as set forth in claim 1, wherein the entanglement portion has a plate-like shape, and the concave shape is recessed from a surface of the entanglement portion in a plate thickness direction.

3. An electromagnetic relay as described in claim 1, wherein the entanglement portion has a plate-like shape, the entanglement portion includes an end face extending in a plate thickness direction, and the concave shape is provided on the end face.

4. The electromagnetic relay according to claim 1, wherein the concave shape includes a plurality of depressions.

5. The electromagnetic relay according to claim 1, wherein the concave shape has a polygonal shape.

6. The electromagnetic relay according to claim 1, wherein the concave shape has a circular shape.

7. The electromagnetic relay according to claim 1, wherein the concave shape has a groove shape.

8. The electromagnetic relay according to claim 1, wherein the concave shape penetrates the entanglement portion.

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