Electromagnetic relays

Abstract

To enable an electromagnetic relay to operate even when a drive shaft and a movable iron core are not fixed.SOLUTION: A movable iron core is movable in movement directions including a contact direction in which a movable contact approaches a fixed contact and a separation direction in which the movable contact separates from the fixed contact. The movable iron core includes a shaft hole extending in the moving direction. The drive shaft is connected to a movable contact piece. The drive shaft is passed through the shaft hole. The drive shaft is fixed to the movable iron core. The coil generates magnetic force that moves the movable iron core in the movement direction. A stopper is connected to the drive shaft. The stopper restricts the movement of the movable iron core relative to the drive shaft in the movement direction.SELECTED DRAWING: Figure 1

Description

[Technical Field]

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

[0002] Some electromagnetic relays have a movable contact piece and a movable iron core connected via a drive shaft (see, for example, Patent Document 1). The movable iron core moves due to the magnetic force generated by the coil. The drive shaft and movable contact piece move together with the movable iron core, thereby opening and closing the contacts. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-96474 Summary of the Invention [Problem to be solved by the invention]

[0004] In the above-mentioned electromagnetic relay, the drive shaft is fixed to the movable core by a fixing means such as welding, screws, or crimping. If the fixing means is damaged by factors such as heat or impact, the movement of the movable core is no longer transmitted to the drive shaft. As a result, the contacts cannot be opened or closed. The object of the present invention is to enable the operation of the electromagnetic relay even when the fixation between the drive shaft and the movable core is damaged. [Means for solving the problem]

[0005] An electromagnetic relay according to one aspect of the present invention comprises a fixed contact, a movable contact, a movable contact piece, a movable iron core, a drive shaft, a coil, and a stopper. The movable contact faces the fixed contact. The movable contact piece is connected to the movable contact. The movable iron core is movable in a movement direction including a contact direction in which the movable contact approaches the fixed contact and a separation direction in which the movable contact moves away from the fixed contact. The movable iron core includes an axial hole extending in the movement direction. The drive shaft is connected to the movable contact piece. The drive shaft passes through the axial hole. The drive shaft is fixed to the movable iron core. The coil generates a magnetic force that moves the movable iron core in the movement direction. The stopper is connected to the drive shaft. The stopper restricts movement of the movable iron core in the movement direction relative to the drive shaft.

[0006] In the electromagnetic relay according to this aspect, when the fixation between the drive shaft and the movable core is broken, the stopper restricts movement of the movable core in the direction of movement relative to the drive shaft. Therefore, even if the fixation between the drive shaft and the movable core is broken, the drive shaft can move together with the movable core. As a result, the electromagnetic relay can operate even if the fixation between the drive shaft and the movable core is broken.

[0007] The stopper may be larger than the shaft hole. In this case, the stopper is prevented from coming off the shaft hole. As a result, the stopper restricts movement of the movable iron core in the movement direction relative to the drive shaft.

[0008] The shaft hole may include a first hole and a second hole. The first hole may extend in the movement direction. The second hole may extend in the movement direction. The second hole may be in communication with the first hole. The second hole may be larger than the first hole. The drive shaft may be passed through the first hole. A stopper may be disposed in the second hole. The stopper may be larger than the first hole. In this case, the stopper is prevented from coming off the first hole. As a result, the stopper restricts movement of the movable iron core in the movement direction relative to the drive shaft. Furthermore, because the stopper is disposed in the second hole, the space required for disposing the stopper can be reduced.

[0009] The electromagnetic relay may further include an intermediate component. The intermediate component may be separate from the stopper. The intermediate component may be sandwiched between the stopper and the movable core. In this case, damage to the stopper or the movable core can be suppressed.

[0010] The intermediate part may be made of a different material from the stopper. In this case, for example, by making the intermediate part from a material softer than the stopper and the movable iron core, damage to the stopper or the movable iron core can be suppressed.

[0011] The stopper may be formed integrally with the drive shaft, which reduces the number of assembly steps, or the stopper may be formed separately from the drive shaft, which makes it easier to manufacture the drive shaft and the stopper.

[0012] The stopper may be in contact with the movable iron core. In this case, when the fixation between the drive shaft and the movable iron core is lost, the stopper immediately restricts movement of the movable iron core in the movement direction relative to the drive shaft.

[0013] The stopper may be spaced apart from the movable core in the direction of movement. The distance between the stopper and the movable core in the direction of movement may be smaller than the range of movement of the movable core in the contact direction after the movable contact comes into contact with the fixed contact. In this case, when the fixation between the drive shaft and the movable core is lost, the stopper moves to a position where it contacts the movable core, and at that position, restricts movement of the movable core in the direction of movement relative to the drive shaft. This causes the drive shaft to move together with the movable core. Then, from the state where the movable contact comes into contact with the fixed contact, the drive shaft can be moved further in the contact direction. This ensures the contact force of the contacts.

[0014] The stopper may be positioned in the contact direction relative to the movable core. In this case, the stopper restricts movement of the movable core relative to the drive shaft in the contact direction. Therefore, even if the fixation between the drive shaft and the movable core is lost, the movable contact can be brought into contact with the fixed contact.

[0015] The stopper may be located in the opening direction relative to the movable core. In this case, the stopper restricts movement of the movable core in the opening direction relative to the drive shaft. Therefore, even if the fixation between the drive shaft and the movable core is lost, the movable contact can be opened from the fixed contact.

[0016] The stopper may be located within the movable core. In this case, the stopper restricts movement of the movable core in both the contact direction and the separation direction relative to the drive shaft. Therefore, even if the fixation between the drive shaft and the movable core is lost, the movable contact can be brought into contact with the fixed contact and can be separated from the fixed contact.

[0017] The stopper may include a first stopper and a second stopper. The first stopper may be located in the separation direction relative to the movable iron core. The second stopper may be located in the contact direction relative to the movable iron core. In this case, the first stopper restricts movement of the movable iron core in the separation direction relative to the drive shaft. The second stopper restricts movement of the movable iron core in the contact direction relative to the drive shaft. Therefore, even if the fixation between the drive shaft and the movable iron core is lost, the movable contact can be brought into contact with the fixed contact, and the movable contact can be separated from the fixed contact.

[0018] The movable core may include a slit. The slit may be in communication with the shaft hole. The slit may extend in the movement direction and in a lateral direction perpendicular to the movement direction. In this case, the drive shaft can be easily attached to the movable core through the slit.

[0019] The movable core may include a plurality of segments separated at a separation plane passing through the shaft hole. In this case, the drive shaft can be easily attached to the movable core by sandwiching the drive shaft between the segments and fixing the segments to each other. [Effects of the Invention]

[0020] According to the present invention, the electromagnetic relay can be operated even when the fixation between the drive shaft and the movable iron core is lost. [Brief explanation of the drawings]

[0021] [Figure 1] 1 is a cross-sectional view of an electromagnetic relay according to a first embodiment. [Figure 2] 1 is a cross-sectional view of an electromagnetic relay according to a first embodiment. [Figure 3] 1 is a cross-sectional view of an electromagnetic relay according to a first embodiment. [Figure 4] FIG. 4 is a cross-sectional view showing a stopper according to a first modified example of the first embodiment. [Figure 5] FIG. 10 is a cross-sectional view showing a stopper according to a second modified example of the first embodiment. [Figure 6] FIG. 10 is a cross-sectional view showing a stopper according to a third modified example of the first embodiment. [Figure 7] FIG. 10 is a cross-sectional view showing a stopper according to a fourth modified example of the first embodiment. [Figure 8] FIG. 10 is a cross-sectional view showing a stopper according to a fifth modified example of the first embodiment. [Figure 9A] FIG. 10 is a cross-sectional view showing a stopper according to a sixth modified example of the first embodiment. [Figure 9B] FIG. 10 is a cross-sectional view showing a stopper according to a sixth modified example of the first embodiment. [Figure 10A] FIG. 13 is a cross-sectional view showing a stopper according to a seventh modified example of the first embodiment. [Figure 10B] FIG. 13 is a cross-sectional view showing a stopper according to a seventh modified example of the first embodiment. [Figure 11] FIG. 10 is a cross-sectional view showing a stopper according to a second embodiment. [Figure 12] FIG. 10 is a cross-sectional view showing a stopper according to a first modified example of the second embodiment. [Figure 13] FIG. 10 is a cross-sectional view showing a stopper according to a second modified example of the second embodiment. [Figure 14] FIG. 10 is a cross-sectional view showing a stopper according to a third modified example of the second embodiment. [Figure 15] FIG. 10 is a cross-sectional view showing a stopper according to a fourth modified example of the second embodiment. [Figure 16] FIG. 10 is a cross-sectional view showing a stopper according to a fifth modified example of the second embodiment. [Figure 17] FIG. 10 is a cross-sectional view showing a stopper according to a sixth modified example of the second embodiment. [Figure 18A] FIG. 13 is a cross-sectional view showing a stopper according to a seventh modified example of the second embodiment. [Figure 18B] FIG. 13 is a cross-sectional view showing a stopper according to a seventh modified example of the second embodiment. [Figure 19A] FIG. 13 is a cross-sectional view showing a stopper according to an eighth modified example of the second embodiment. [Figure 19B] FIG. 13 is a cross-sectional view showing a stopper according to an eighth modified example of the second embodiment. [Figure 20] FIG. 13 is a cross-sectional view showing a stopper according to a ninth modified example of the second embodiment. [Figure 21] FIG. 10 is a cross-sectional view showing a stopper according to a third embodiment. [Figure 22] FIG. 11 is a cross-sectional view showing a stopper according to a first modified example of the third embodiment. [Figure 23] FIG. 11 is a cross-sectional view showing a stopper according to a second modified example of the third embodiment. [Figure 24] FIG. 11 is a cross-sectional view showing a movable core according to a third modified example of the third embodiment. [Figure 25] FIG. 11 is a cross-sectional view showing a stopper according to a fourth modified example of the third embodiment. [Figure 26] FIG. 11 is a cross-sectional view showing a movable core according to a fifth modified example of the third embodiment. [Figure 27] FIG. 10 is a cross-sectional view showing a stopper according to a fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0022] An embodiment of an electromagnetic relay 1 according to one aspect of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view of the electromagnetic relay 1 according to the first embodiment. As shown in FIG. 1, the electromagnetic relay 1 includes a case 2, a contact device 3, and a drive device 4. The case 2 is made of an insulating material such as resin. However, the case 2 may be made of other materials such as ceramic. The contact device 3 is housed within the case 2.

[0023] The contact device 3 includes a first fixed terminal 6, a second fixed terminal 7, a movable contact 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.

[0024] In the following description, the direction from the first movable contact 12 to the first fixed contact 10 is defined as the "contact direction (Z1)." The contact direction is the direction in which the movable contacts 12, 13 approach the fixed contacts 10, 11. The direction from the first fixed contact 10 to the first movable contact 12 is defined as the "separation direction (Z2)." The separation direction is the direction in which the movable contacts 12, 13 move away from the fixed contacts 10, 11. The movement directions (Z1, Z2) include the contact direction (Z1) and the separation direction (Z2).

[0025] The first fixed terminal 6, the second fixed terminal 7, the movable contact 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 conductive materials. For example, the first fixed terminal 6, the second fixed terminal 7, and the movable contact piece 8 are made of a metallic material known as a terminal material, such as phosphor bronze, beryllium copper, brass, or tough pitch copper. However, the first fixed terminal 6, the second fixed terminal 7, and the movable contact piece 8 may be made of a material different from these. 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.

[0026] The first fixed terminal 6 and the second fixed terminal 7 are arranged at an interval from each other in the horizontal direction (X1, X2). The horizontal direction (X1, X2) is a direction perpendicular to the movement direction (Z1, Z2). 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 case 2.

[0027] The movable contact piece 8, the first movable contact 12, and the second movable contact 13 are arranged in the case 2. The first movable contact 12 and the second movable contact 13 are connected to the movable contact piece 8. The first movable contact 12 faces the first fixed contact 10. The first movable contact 12 can come into contact with and separate from the first fixed contact 10. The second movable contact 13 faces the second fixed contact 11. The second movable contact 13 can come into contact with and separate from the second fixed contact 11. The first movable contact 12 is arranged at a distance from the second movable contact 13 in the lateral direction (X1, X2).

[0028] The movable contact piece 8 is movable in movement directions (Z1, Z2). That is, the movable contact piece 8 is movable in a contact direction (Z1) and a separation direction (Z2). The movable contact piece 8 is movable between a closed position and an open position. As shown in FIG. 1, when the movable contact piece 8 is in the open position, the movable contacts 12, 13 are separated from the fixed contacts 10, 11. As shown in FIG. 2, when the movable contact piece 8 is in the closed position, the movable contacts 12, 13 are in contact with the fixed contacts 10, 11.

[0029] The movable mechanism 9 supports the movable contact piece 8. The movable mechanism 9 includes a drive shaft 15 and a contact spring 16. The drive shaft 15 is connected to the movable contact piece 8. The drive shaft 15 extends in the movement direction (Z1, Z2) and penetrates the movable contact piece 8 in the movement direction (Z1, Z2). The movable contact piece 8 includes a hole 17. The hole 17 extends in the movement direction (Z1, Z2) in the movable contact piece 8. The drive shaft 15 is passed through the hole 17. The drive shaft 15 is movable in the movement direction (Z1, Z2) together with the movable contact piece 8. Furthermore, the drive shaft 15 is movable in the movement direction (Z1, Z2) relative to the movable contact piece 8.

[0030] A first holder 18 and a second holder 19 are fixed to the drive shaft 15. The movable contact piece 8 is disposed between the first holder 18 and the second holder 19. The first holder 18 and the second holder 19 are larger than the hole 17. The first holder 18 restricts movement of the drive shaft 15 in the separation direction (Z2). The contact spring 16 is disposed between the movable contact piece 8 and the second holder 19. The contact spring 16 biases the movable contact piece 8 in the contact direction (Z1).

[0031] The driving device 4 includes a coil 21, a spool 22, a movable iron core 23, a fixed iron core 24, a yoke 25, and a return spring 26. The driving device 4 uses electromagnetic force to move the movable contact piece 8 between an open position and a closed position via the moving mechanism 9. The coil 21 is wound around the spool 22. The movable iron core 23 and the fixed iron core 24 are disposed within the spool 22. The coil 21 generates a magnetic force that moves the movable iron core 23 in the movement direction.

[0032] The movable iron core 23 is connected to the drive shaft 15. The movable iron core 23 is movable in the movement directions (Z1, Z2). The fixed iron core 24 is disposed opposite the movable iron core 23. The return spring 26 biases the movable iron core 23 in the opening direction (Z2).

[0033] The movable iron core 23 includes a shaft hole 27 extending in the movement direction (Z1, Z2). The shaft hole 27 penetrates the movable iron core 23 in the movement direction (Z1, Z2). The drive shaft 15 passes through the shaft hole 27. The drive shaft 15 is fixed to the movable iron core 23 by, for example, welding. However, the drive shaft 15 may also be fixed to the movable iron core 23 by other fixing means such as screws or caulking.

[0034] A stopper 28 is connected to the drive shaft 15. The stopper 28 is connected to an end of the drive shaft 15. The stopper 28 is located in the separation direction (Z2) relative to the movable iron core 23. The stopper 28 protrudes from the drive shaft 15 in the outer diameter direction of the drive shaft 15. The stopper 28 is formed integrally with the drive shaft 15. The stopper 28 is in contact with the movable iron core 23. The outer diameter of the stopper 28 is larger than the inner diameter of the shaft hole 27. The stopper 28 restricts movement of the movable iron core 23 relative to the drive shaft 15 in the separation direction (Z2).

[0035] In the electromagnetic relay 1, when the coil 21 is energized, the movable core 23 is attracted to the fixed core 24 by the magnetic force of the magnetic field generated by the coil 21. As a result, the movable core 23 and the drive shaft 15 move in the contact direction (Z1) against the biasing force of the return spring 26. As a result, the movable contact piece 8 moves in the contact direction (Z1), and as shown in FIG. 3, the first movable contact 12 contacts the first fixed contact 10, and the second movable contact 13 contacts the second fixed contact 11. Thereafter, as the movable core 23 moves further in the contact direction (Z1), the drive shaft 15 moves in the contact direction (Z1) relative to the movable contact piece 8, as shown in FIG. 2. As a result, the contact spring 16 is compressed, ensuring a high contact force between the movable contacts 12, 13 and the fixed contacts 10, 11.

[0036] When the current to the coil 21 is turned off, the movable iron core 23 and the drive shaft 15 move in the opening direction (Z2) due to the biasing force of the return spring 26. As a result, the movable contact 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.

[0037] In the electromagnetic relay 1 according to the first embodiment described above, when the fixation between the drive shaft 15 and the movable iron core 23 is lost, the stopper 28 restricts movement of the movable iron core 23 in the separation direction (Z2) relative to the drive shaft 15. Therefore, even if the fixation between the drive shaft 15 and the movable iron core 23 is lost, the drive shaft 15 can move in the separation direction (Z2) together with the movable iron core 23. As a result, in the electromagnetic relay 1, the movable contacts 12 and 13 can be separated from the fixed contacts 10 and 11 even if the fixation between the drive shaft 15 and the movable iron core 23 is lost.

[0038] The shape of the stopper 28 is not limited to the above-described shape and may be modified. For example, Fig. 4 is a diagram showing the stopper 28 according to a first modified example of the first embodiment. As shown in Fig. 4, the stopper 28 may have a shape in which the outer shape of the stopper 28 increases in size in the contact direction (Z1).

[0039] FIG. 5 is a diagram showing a stopper 28 according to a second modification of the first embodiment. As shown in FIG. 5, the shaft hole 27 may include a first hole 31 and a second hole 32. The first hole 31 may extend in the movement direction (Z1, Z2). The second hole 32 may be located in the separation direction (Z2) relative to the first hole 31. The second hole 32 may extend in the movement direction (Z1, Z2) and communicate with the first hole 31. The inner diameter of the second hole 32 may be larger than the inner diameter of the first hole 31. The drive shaft 15 may be passed through the first hole 31. The outer diameter of the stopper 28 may be larger than the inner diameter of the first hole 31 but smaller than the inner diameter of the second hole 32. The stopper 28 may be disposed within the second hole 32.

[0040] Fig. 6 is a diagram showing a stopper 28 according to a third modified example of the first embodiment. As shown in Fig. 6, the inner diameter of the second hole 32 may increase in the separation direction (Z2). The stopper 28 may have a shape that follows the inner surface of the second hole 32. In other words, the outer shape of the stopper 28 may increase in the separation direction (Z2).

[0041] Fig. 7 is a diagram showing a stopper 28 according to a fourth modified example of the first embodiment. When the movable contact piece 8 is in the open position, the movable core 23 contacts the yoke 25. As shown in Fig. 7, the yoke 25 may include a recess 33. When the movable contact piece 8 is in the open position, the stopper 28 may be located within the recess 33. Note that when the movable contact piece 8 is in the open position, the movable core 23 may contact the case instead of the yoke 25. In this case, the recess 33 may be provided in the case.

[0042] Fig. 8 is a diagram showing a stopper 28 according to a fifth modified example of the first embodiment. As shown in Fig. 8, the electromagnetic relay 1 may further include an intermediate component 34. The intermediate component 34 may be separate from the stopper 28 and may be sandwiched between the stopper 28 and the movable iron core 23. The intermediate component 34 may be formed of a material different from that of the stopper 28. For example, the stopper may be made of metal, and the intermediate component 34 may be made of resin. Alternatively, the stopper may be made of metal, and the intermediate component 34 may be made of a metal that is softer than the stopper.

[0043] 9A and 9B are views showing a stopper 28 according to a sixth modified example of the first embodiment. FIG. 9B is a cross-sectional view taken along line AA in FIG. 9A. As shown in FIG. 9A, the stopper 28 may be separate from the drive shaft 15. The drive shaft 15 may include a recessed groove 35. The stopper 28 may be attached to the drive shaft 15 by being engaged with the recessed groove 35. As shown in FIG. 9B, the stopper 28 may include a hole 36 and a slit 37 communicating with the hole 36. The slit 37 may extend in the lateral direction (X1, X2). The stopper 28 may be attached to the drive shaft 15 in the lateral direction (X1, X2) through the slit 37.

[0044] 10A and 10B are views showing a stopper 28 according to a seventh modified example of the first embodiment. Fig. 10B is a cross-sectional view taken along line BB in Fig. 10A. As shown in Figs. 10A and 10B, the drive shaft 15 may include a hole 38 extending in the lateral direction (X1, X2). The stopper 28 may be inserted into the hole 38.

[0045] Next, an electromagnetic relay 1 according to a second embodiment will be described. Fig. 11 is a cross-sectional view showing the stopper 28 of the electromagnetic relay 1 according to the second embodiment. As shown in Fig. 11, in the electromagnetic relay 1 according to the second embodiment, the stopper 28 is positioned in the contact direction (Z1) with respect to the movable iron core 23. Other configurations of the electromagnetic relay 1 according to the second embodiment are the same as those of the electromagnetic relay 1 according to the first embodiment.

[0046] In the electromagnetic relay 1 according to the second embodiment, when the fixation between the drive shaft 15 and the movable iron core 23 is lost, the stopper 28 restricts movement of the movable iron core 23 in the contact direction (Z1) relative to the drive shaft 15. Therefore, even if the fixation between the drive shaft 15 and the movable iron core 23 is lost, the drive shaft 15 can move in the contact direction (Z1) together with the movable iron core 23. As a result, in the electromagnetic relay 1, the movable contacts 12 and 13 can be brought into contact with the fixed contacts 10 and 11 even if the fixation between the drive shaft 15 and the movable iron core 23 is lost.

[0047] The shape of the stopper 28 is not limited to the above-described shape and may be modified. For example, Fig. 12 is a diagram showing the stopper 28 according to a first modified example of the second embodiment. As shown in Fig. 12, the stopper 28 may have a shape in which the outer shape of the stopper 28 increases in the separation direction (Z2).

[0048] Fig. 13 is a view showing a stopper 28 according to a second modified example of the second embodiment. As shown in Fig. 13, the drive shaft 15 may include a first shaft 41 and a second shaft 42. The outer diameter of the first shaft 41 may be larger than the outer diameter of the second shaft 42. The second shaft 42 may be disposed within the shaft hole 27. The outer diameter of the first shaft 41 may be larger than the inner diameter of the shaft hole 27. The stopper 28 may be a step portion between the first shaft 41 and the second shaft 42.

[0049] FIG. 14 is a diagram showing a stopper 28 according to a third modified example of the second embodiment. As shown in FIG. 14, the shaft hole 27 may include a first hole 43 and a second hole 44. The first hole 43 may extend in the movement direction (Z1, Z2). The second hole 44 may be located in the contact direction (Z1) relative to the first hole 43. The second hole 44 may extend in the movement direction (Z1, Z2) and communicate with the first hole 43. The inner diameter of the second hole 44 may be larger than the inner diameter of the first hole 43. The drive shaft 15 may be passed through the first hole 43. The outer diameter of the stopper 28 may be larger than the inner diameter of the first hole 43 but smaller than the inner diameter of the second hole 44. The stopper 28 may be disposed within the second hole 44.

[0050] Fig. 15 is a diagram showing a stopper 28 according to a fourth modified example of the second embodiment. As shown in Fig. 15, the inner diameter of the second hole 44 may expand in the contact direction (Z1). The stopper 28 may have a shape that follows the inner surface of the second hole 44. In other words, the outer shape of the stopper 28 may expand in the contact direction (Z1).

[0051] 16 is a diagram showing a stopper 28 according to a fifth modified example of the second embodiment. When the movable contact piece 8 is in the closed position, the movable core 23 contacts the fixed core 24. As shown in FIG. 16, the fixed core 24 may include a recess 45. When the movable contact piece 8 is in the closed position, the stopper 28 may be located within the recess 45.

[0052] Fig. 17 is a diagram showing a stopper 28 according to a sixth modified example of the second embodiment. As shown in Fig. 17, the electromagnetic relay 1 may further include an intermediate component 46. The intermediate component 46 may be separate from the stopper 28 and may be sandwiched between the stopper 28 and the movable iron core 23. The intermediate component 46 may be formed of a material different from that of the stopper 28. For example, the stopper may be made of metal, and the intermediate component 46 may be made of resin. Alternatively, the stopper may be made of metal, and the intermediate component 46 may be made of a metal that is softer than the stopper.

[0053] 18A and 18B are views showing a stopper 28 according to a seventh modified example of the second embodiment. FIG. 18B is a cross-sectional view taken along CC in FIG. 18A. As shown in FIG. 18A, the stopper 28 may be separate from the drive shaft 15. The drive shaft 15 may include a recessed groove 47. The stopper 28 may be attached to the drive shaft 15 by being engaged with the recessed groove 47. As shown in FIG. 18B, the stopper 28 may include a hole 48 and a slit 49 communicating with the hole 48. The slit 49 may extend in the lateral direction (X1, X2). The stopper 28 may be attached to the drive shaft 15 in the lateral direction (X1, X2) through the slit 49.

[0054] 19A and 19B are views showing a stopper 28 according to an eighth modified example of the second embodiment. FIG. 19B is a cross-sectional view taken along line DD in FIG. 19A. As shown in FIGS. 19A and 19B, the drive shaft 15 may include a hole 50 extending in the lateral direction (X1, X2). The stopper 28 may be inserted into the hole 50.

[0055] FIG. 20 is a diagram showing a stopper 28 according to a ninth modification of the second embodiment. As shown in FIG. 20, the stopper 28 may be spaced apart from the movable core 23 in the contact direction (Z1). Similar to FIG. 3, FIG. 20 shows the positions of the drive shaft 15 and the movable core 23 when the movable contacts 12, 13 contact the fixed contacts 10, 11. As shown in FIG. 20, the distance D1 between the stopper 28 and the movable core 23 in the movement direction (Z1, Z2) may be smaller than the movable range D2 of the movable core 23 in the contact direction (Z1) after the movable contacts 12, 13 contact the fixed contacts 10, 11. The movable range D2 of the movable core 23 is the distance between the movable core 23 and the fixed core 24 in the movement direction (Z1, Z2).

[0056] In this case, even if the fixation between the drive shaft 15 and the movable iron core 23 is lost, the stopper 28 restricts the movement of the movable iron core 23 in the contact direction (Z1). Therefore, the drive shaft 15 moves in the contact direction (Z1) together with the movable iron core 23. At that time, the drive shaft 15 can move in the contact direction (Z1) by a distance (D2-D1) corresponding to the difference between the distance D1 between the stopper 28 and the movable iron core 23 and the movable range D2 of the movable iron core 23. As a result, the contact spring 26 is compressed, and a contact force can be obtained between the movable contacts 12, 13 and the fixed contacts 10, 11.

[0057] Next, an electromagnetic relay 1 according to a third embodiment will be described. FIG. 21 is a cross-sectional view showing the drive shaft 15 and movable core 23 of the electromagnetic relay 1 according to the third embodiment. As shown in FIG. 21, the electromagnetic relay 1 according to the third embodiment includes a first stopper 28A and a second stopper 28B. The first stopper 28A, like the stopper 28 according to the first embodiment, is positioned in the separation direction (Z2) relative to the movable core 23. The second stopper 28B, like the stopper 28 according to the second embodiment, is positioned in the contact direction (Z1) relative to the movable core 23. Other configurations of the electromagnetic relay 1 according to the third embodiment are the same as those of the electromagnetic relay 1 according to the first embodiment.

[0058] In the electromagnetic relay 1 according to the third embodiment, when the fixation between the drive shaft 15 and the movable iron core 23 is lost, the first stopper 28A restricts movement of the movable iron core 23 relative to the drive shaft 15 in the separation direction (Z2). Therefore, even if the fixation between the drive shaft 15 and the movable iron core 23 is lost, the drive shaft 15 can move in the separation direction (Z2) together with the movable iron core 23. Furthermore, when the fixation between the drive shaft 15 and the movable iron core 23 is lost, the second stopper 28B restricts movement of the movable iron core 23 relative to the drive shaft 15 in the contact direction (Z1). Therefore, even if the fixation between the drive shaft 15 and the movable iron core 23 is lost, the drive shaft 15 can move in the contact direction (Z1) together with the movable iron core 23. As a result, in the electromagnetic relay 1, the movable contacts 12, 13 and the fixed contacts 10, 11 can be opened and closed even if the fixation between the drive shaft 15 and the movable iron core 23 is lost.

[0059] The stoppers 28A, 28B are not limited to the above-described shapes and may be modified. For example, FIG. 22 is a diagram illustrating stoppers 28A, 28B according to a first modified example of the third embodiment. As shown in FIG. 22, the first stopper 28A may be separate from the drive shaft 15, and the second stopper 28B may be integral with the drive shaft 15. Alternatively, the first stopper 28A may be integral with the drive shaft 15, and the second stopper 28B may be separate from the drive shaft 15. FIG. 23 is a diagram illustrating stoppers 28A, 28B according to a second modified example of the third embodiment. As shown in FIG. 23, both the first stopper 28A and the second stopper 28B may be separate from the drive shaft 15.

[0060] FIG. 24 is a diagram showing a movable core 23 according to a third modified example of the third embodiment. FIG. 24 shows a cross section of the movable core 23 as viewed in the movement direction (Z1, Z2). As shown in FIG. 24, the movable core 23 may include a slit 51 communicating with the shaft hole 27. The slit 51 may extend in the movement direction (Z1, Z2) and the lateral direction (X1, X2). The slit 51 may penetrate the movable core 23 in the movement direction (Z1, Z2). In this case, the drive shaft 15 can be attached to the movable core 23 through the slit 51. Therefore, even if both the first stopper 28A and the second stopper 28B are integral with the drive shaft 15 as shown in FIG. 21, the drive shaft 15 can be easily attached to the movable core 23.

[0061] Fig. 25 is a diagram showing stoppers 28A, 28B according to a fourth modified example of the third embodiment. When the movable core 23 includes the slit 51 as described above, the electromagnetic relay 1 may include a guide 52 as shown in Fig. 25. The guide 52 may extend in the movement direction (Z1, Z2). The movable core 23 may be disposed within the guide 52. The guide 52 may guide the movement of the movable core 23 in the movement direction (Z1, Z2).

[0062] FIG. 26 is a diagram showing a movable core 23 according to a fifth modified example of the third embodiment. FIG. 26 shows a cross section of the movable core 23 as viewed from the movement direction (Z1, Z2). As shown in FIG. 26, the movable core 23 may include a plurality of divided bodies 23A, 23B divided at a division plane 53 passing through the shaft hole 27. The division plane 53 may pass through the center of the movable core 23. The division plane 53 may extend in the movement direction (Z1, Z2) and the lateral direction (X1, X2). The movable core 23 may include a first divided body 23A and a second divided body 23B. In this case, the drive shaft 15 is attached to the movable core 23 by sandwiching the drive shaft 15 between the first divided body 23A and the second divided body 23B and fixing the first divided body 23A and the second divided body 23B to each other. 21, even if both the first stopper 28A and the second stopper 28B are integral with the drive shaft 15, the drive shaft 15 can be easily attached to the movable iron core 23. The number of segments is not limited to two and may be more than two.

[0063] The shape of the first stopper 28A is not limited to the above-described shape and may be modified. For example, the first stopper 28A may have the shapes of the first to seventh modified examples of the first embodiment. The second stopper 28B may have the shapes of the first to ninth modified examples of the second embodiment.

[0064] Next, an electromagnetic relay 1 according to a fourth embodiment will be described. Fig. 27 is a cross-sectional view showing a stopper 28 of the electromagnetic relay 1 according to the fourth embodiment. As shown in Fig. 27, in the electromagnetic relay 1 according to the third embodiment, the stopper 28 is located inside the movable core 23. As in the fifth modified example of the third embodiment, the movable core 23 includes a plurality of divided bodies 23A, 23B divided at a dividing plane passing through the shaft hole 27.

[0065] Specifically, the movable core 23 includes a first divided body 23A and a second divided body 23B. The first divided body 23A includes a first recess 54A within the shaft hole 27. The second divided body 23B includes a second recess 54B within the shaft hole 27. The stopper 28 is disposed within the first recess 54A and the second recess 54B. The drive shaft 15 is attached to the movable core 23 by sandwiching the drive shaft 15 between the first divided body 23A and the second divided body 23B and fixing the first divided body 23A and the second divided body 23B to each other. The number of divided bodies is not limited to two and may be more than two. Other configurations of the electromagnetic relay 1 according to the fourth embodiment are the same as those of the electromagnetic relay 1 according to the first embodiment.

[0066] In the electromagnetic relay 1 according to the fourth embodiment, when the fixation between the drive shaft 15 and the movable iron core 23 is lost, the stopper 28 restricts movement of the movable iron core 23 relative to the drive shaft 15 in the separation direction (Z2). Therefore, even if the fixation between the drive shaft 15 and the movable iron core 23 is lost, the drive shaft 15 can move together with the movable iron core 23 in the separation direction (Z2). Furthermore, when the fixation between the drive shaft 15 and the movable iron core 23 is lost, the stopper 28 restricts movement of the movable iron core 23 relative to the drive shaft 15 in the contact direction (Z1). Therefore, even if the fixation between the drive shaft 15 and the movable iron core 23 is lost, the drive shaft 15 can move together with the movable iron core 23 in the contact direction (Z1). As a result, in the electromagnetic relay 1, the movable contacts 12, 13 and the fixed contacts 10, 11 can be opened and closed even if the fixation between the drive shaft 15 and the movable iron core 23 is lost.

[0067] The stopper 28 of the electromagnetic relay 1 according to the fourth embodiment is not limited to the above-described shape and may be modified. The stopper 28 may have the same shape as any of the modified examples of the first to third embodiments described above.

[0068] 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.

[0069] The structures of the contact device 3 and the drive device 4 are not limited to those in the above embodiment and may be modified. For example, the number of fixed contacts and movable contacts is not limited to two and may be more than two. The fixed contacts 10 and 11 may be integral with the fixed terminals 6 and 7. The movable contacts 12 and 13 may be integral with the movable contact piece 8. In the above embodiment, the drive shaft 15 is pushed out from the drive device 4, causing the movable contacts 12 and 13 to contact the fixed contacts 10 and 11. However, the drive shaft 15 may be pulled into the drive device 4, causing the movable contacts 12 and 13 to contact the fixed contacts 10 and 11. The lateral direction may be any direction perpendicular to the movement direction (Z1, Z2), and may be a direction different from the lateral direction (X1, X2) in the above embodiment. [Industrial Applicability]

[0070] According to the present invention, the electromagnetic relay can be operated even when the fixation between the drive shaft and the movable iron core is lost. [Explanation of symbols]

[0071] 10: First fixed contact, 12: First moving contact, 8: Moving contact piece, 15: Drive shaft, 21: Coil, 23: Moving core, 23A: First divided body, 23B: Second divided body, 27: Shaft hole, 28: Stopper, 28A: First stopper, 28B: Second stopper, 31: First hole, 32: Second hole, 34: Intermediate part, 43: First hole, 44: Second hole, 46: Intermediate part, 51: Slit

Claims

1. A fixed contact; a movable contact facing the fixed contact; a movable contact piece connected to the movable contact; a movable core that is movable in a movement direction including a contact direction in which the movable contact approaches the fixed contact and a separation direction in which the movable contact moves away from the fixed contact, and that includes an axial hole that extends in the movement direction; a drive shaft connected to the movable contact piece, passed through the shaft hole, and fixed to the movable core by welding, screws, or caulking; a coil that generates a magnetic force that moves the movable core in the movement direction; a stopper connected to the drive shaft and configured to restrict movement of the movable iron core relative to the drive shaft in the movement direction; Equipped with the stopper is disposed in the separation direction relative to the movable core, When the fixation between the drive shaft and the movable iron core is lost, the supply of current to the coil is stopped, and the stopper restricts the movement of the movable iron core relative to the drive shaft in the separation direction, so that the drive shaft moves in the separation direction together with the movable iron core, causing the movable contact to separate from the fixed contact; however, the movable iron core becomes movable in the contact direction relative to the drive shaft, so that the movable contact cannot come into contact with the fixed contact even if the supply of current to the coil is resumed. Electromagnetic relay.

2. The outer diameter of the stopper is larger than the inner diameter of the shaft hole.

2. The electromagnetic relay according to claim 1.

3. The axial hole is a first hole extending in the movement direction; a second hole extending in the movement direction, communicating with the first hole, and larger than the first hole; Including, The drive shaft is passed through the first hole, the stopper is disposed in the second hole; The outer diameter of the stopper is larger than the inner diameter of the first hole.

2. The electromagnetic relay according to claim 1.

4. The stopper is formed integrally with the drive shaft.

4. An electromagnetic relay according to claim 1.

5. The stopper is separate from the drive shaft.

4. An electromagnetic relay according to claim 1.

6. The stopper is in contact with the movable iron core.

6. An electromagnetic relay according to claim 1.

7. the stopper is spaced apart from the movable iron core in the moving direction, a distance between the stopper and the movable iron core in the movement direction is smaller than a range of movement of the movable iron core in the contact direction after the movable contact comes into contact with the fixed contact; 7. An electromagnetic relay according to claim 1.

8. the movable core includes a slit communicating with the axial hole and extending in the moving direction and a lateral direction perpendicular to the moving direction; 8. An electromagnetic relay according to claim 1.

9. the movable core includes a plurality of divided bodies divided at dividing planes passing through the axial hole, 9. An electromagnetic relay according to claim 1.

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