Contact device and electromagnetic relay

Abstract

This contact device (2) comprises a pair of fixed contacts (211), a movable contact (22), and a holder (23). The movable contact (22) contacts and separates from the pair of fixed contacts (211) in a vertical direction (Y2) orthogonal to a left-right direction (Y1). The holder (23) holds the movable contact (22). A movable shaft (24) moves the holder (23) in the vertical direction (Y2) so that the movable contact (22) comes into contact with and separates from the pair of fixed contacts (211). The holder (23) includes an upper yoke (51). The upper yoke (51) is disposed on the movable contact (22) on the side of the pair of fixed contacts (211) and covers a portion of the movable contact (22). A facing surface (A51a) of the upper yoke (51) is provided with a protruding region (A51d) that contacts and separates from a facing surface (A22a) of the movable contact (22). The protruding region (A51d) has a quadrangular shape in a plan view from the vertical direction (Y2).

Description

Contact device and electromagnetic relay

[0001] The present disclosure generally relates to contact devices and electromagnetic relays, and more particularly relates to a contact device including a pair of fixed contacts and a pair of movable contacts, and an electromagnetic relay including the contact device.

[0002] The electromagnetic switching device described in Patent Document 1 includes two fixed contacts arranged side by side left and right, a movable contact, a shaft, and a contact pressure spring. The two fixed contacts are respectively provided at the lower ends of two fixed terminal blocks. The movable contact is disposed below the two fixed contacts so as to be capable of coming into contact with and separating from the two fixed contacts. A movable contact is respectively provided at each portion facing the two fixed contacts on the upper surface of the movable contact. A shaft hole through which the shaft passes is provided in the center of the movable contact. The shaft passes through the shaft hole of the movable contact and is arranged along the vertical direction. A flange portion for preventing the shaft from coming off the shaft hole of the movable contact is provided at the upper end of the shaft. A contact pressure spring that biases the movable contact toward the upper side (the fixed contact side) is disposed below the movable contact.

[0003] In this electromagnetic switching device, when the shaft moves upward, the movable contact moves upward by the biasing force of the contact pressure spring, and the two movable contacts respectively come into contact with the two fixed contacts. Thereby, the two fixed contacts are short-circuited via the movable contact. When the shaft moves downward, the flange portion at the upper end of the shaft abuts against the upper surface of the movable contact to move the movable contact downward, and the two movable contacts are respectively separated from the two fixed contacts. Thereby, the two movable contacts are peeled off from the two fixed contacts.

[0004] Japanese Unexamined Patent Publication No. 2007-294262

[0005] Among the types of electromagnetic relays, there are some that, as described above, use an upper yoke to separate the movable contact from the fixed contact, instead of using a shaft that penetrates the axial hole of the movable contact and has a flange at its upper end to separate the movable contact from the fixed contact. In such an electromagnetic relay, the upper yoke is positioned above the movable contact so as to move up and down in conjunction with the up and down movement of the shaft. The movable contact is then separated from the two fixed contacts by the upper yoke striking the movable contact from above. The lower surface of the upper yoke is provided with a circular convex region in plan view that strikes the upper surface of the movable contact.

[0006] However, since the convex region on the underside of the fixed yoke has a circular shape in plan view, the area of ​​the convex region in plan view is relatively small. Therefore, when such a small area convex region strikes the upper surface of the movable contact, the upper surface of the movable contact gradually becomes concave over time, and this concaveness causes a problem in which the peeling performance when separating the movable contact from the fixed contact decreases.

[0007] A contact device according to one aspect of the present disclosure comprises a pair of fixed contacts arranged in the left-right direction, a movable contact that moves toward and toward the pair of fixed contacts in a vertical direction perpendicular to the left-right direction, a holder for holding the movable contact, and a movable shaft for moving the holder in the vertical direction so that the movable contact moves toward and toward the pair of fixed contacts. The holder includes an upper yoke positioned on the side of the pair of fixed contacts of the movable contact and covering a part of the movable contact, the opposing surfaces of the movable contact and the opposing surfaces of the upper yoke facing each other, a convex region is provided on the first opposing surface which is one of the opposing surfaces of the movable contact and the opposing surface of the upper yoke, the convex region contacts and separates from the second opposing surface which is the other of the opposing surfaces of the movable contact and the opposing surface of the upper yoke, and the convex region has a rectangular shape in a plan view from the vertical direction.

[0008] A contact device according to one aspect of the present disclosure comprises a pair of fixed contacts arranged in the left-right direction, a movable contact that moves toward and toward the pair of fixed contacts in a vertical direction perpendicular to the left-right direction, a holder that holds the movable contact, and a movable shaft that moves the holder in the vertical direction so that the movable contact moves toward and toward the pair of fixed contacts. The holder includes an upper yoke positioned above the movable contact, a lower yoke fixed to the lower surface of the movable contact, a contact pressure spring that biases the lower yoke toward the upper yoke, and a holder body fixed to the upper yoke that holds the movable contact and the lower yoke so that they can be displaced relative to each other in the vertical direction. The lower yoke has a pair of first magnetic pole regions positioned on both sides of the movable contact in the front-rear direction perpendicular to the left-right and vertical directions. The opposing surface of the upper yoke facing the movable contact has a pair of second magnetic pole regions facing the pair of first magnetic pole regions. A pair of convex regions is provided in one of the pair of first magnetic pole regions and the pair of second magnetic pole regions, and the pair of convex regions contact and separate from the other pair of magnetic pole regions.

[0009] An electromagnetic relay according to one aspect of the present disclosure comprises a contact device and an electromagnet device. The electromagnet device drives the movable shaft such that the movable contact moves toward and away from the pair of fixed contacts.

[0010] The contact device and electromagnetic relay according to the above-described embodiment of this disclosure have the effect of improving the peeling performance.

[0011] Figure 1 is a cross-sectional view of the electromagnetic relay according to Embodiment 1, taken along the line X1-X1 in Figure 2. Figure 2 is an external perspective view of the same electromagnetic relay. Figure 3 is a cross-sectional view of the same electromagnetic relay, taken along the line X2-X2 in Figure 2. Figure 4 is a perspective view of the main part of the contact device of the same electromagnetic relay. Figure 5 is an exploded perspective view of the main part of the contact device of the same electromagnetic relay. Figure 6 is a perspective view of the upper yoke of the same contact device. Figure 7 is an explanatory diagram illustrating the operation of the same electromagnetic relay. Figure 8 is an exploded perspective view of a part of the main part of the contact device of the electromagnetic relay according to Embodiment 2. Figure 9 is an explanatory diagram illustrating the operation of the same electromagnetic relay. Figure 10 is a perspective view of the main part of the contact device of the electromagnetic relay according to Embodiment 3. Figure 11 is a cross-sectional view of Figure 10, taken along the line X1-X1.

[0012] The electromagnetic relay 1 and contact device 2 according to the embodiment will be described below with reference to the drawings. The figures referenced in the following embodiments are schematic diagrams, and the ratios of the size and thickness of each component shown in the figures do not necessarily reflect the actual dimensional ratios.

[0013] (Embodiment 1) (1) Overview of the contact device The overview of the contact device 2 according to Embodiment 1 will be described with reference to the schematic diagrams 4 and 5 of the contact device.

[0014] The contact device 2 according to Embodiment 1 comprises a pair of fixed contacts 211 (see Figure 1), a movable contact 22, a holder 23, and a movable shaft 24 (see Figure 1). The pair of fixed contacts 211 are aligned in the left-right direction Y1. The movable contact 22 moves toward and toward the pair of fixed contacts 211 in the up-down direction Y2, which is perpendicular to the left-right direction Y1. The holder 23 holds the movable contact 22. The movable shaft 24 moves the holder 23 in the up-down direction Y2 so that the movable contact 22 moves toward and toward the pair of fixed contacts 211. The holder 23 has a covering portion (upper yoke 51). The covering portion is positioned on the side of the pair of fixed contacts 211 on the movable contact 22 and covers a part of the movable contact 22. On the movable contactor 22, a convex region A51d (see Figure 6) is provided on the first opposing surface (opposing surface A51a in the example of Figure 5) of the surface A22a facing the covering portion and the surface A51a facing the movable contactor 22 on the covering portion, which is the remaining opposing surface, the second opposing surface (for example, opposing surface A22a). The convex region A51d has a rectangular shape when viewed from the vertical direction Y2.

[0015] This configuration improves the peeling performance when separating the movable contact 22 from the pair of fixed contacts 211.

[0016] Furthermore, the upper yoke 51 functions as a covering.

[0017] (2) Components of the electromagnetic relay The electromagnetic relay 1 according to Embodiment 1 comprises a contact device 2, an electromagnet device 3, and a housing 4, as shown in Figures 1 to 3.

[0018] The components of the electromagnetic relay 1 according to this embodiment will be described below with reference to the drawings.

[0019] (2.1) Contact device The contact device 2, as shown in Figures 1 to 3, comprises a pair of fixed terminals 21, a movable contactor 22, a holder 23, a movable shaft 24, a case 25, a connecting body 26, two permanent magnets 27, and two bridging portions 28.

[0020] (2.1.1) Fixed terminals Each of the pair of fixed terminals 21 is formed of a conductive material such as copper, as shown in Figures 1 to 3. Each fixed terminal 21 has a fixed contact 211 and a terminal body 212. The shape of the terminal body 212 is cylindrical. Each fixed terminal 21 is positioned to pass through the through hole 251 of the first body 41 and the case 25. Each fixed terminal 21 is joined to the case 25 by brazing with its upper end protruding from the upper surface of the case 25 and the upper surface of the first body 41.

[0021] Each of the pair of fixed contacts 211 is attached to the lower end of the terminal body 212, as shown in Figures 1 to 3. More specifically, each fixed contact 211 is fixed to the lower end of the terminal body 212. The pair of fixed contacts 211 are arranged in the left-right direction Y1 (first direction). Each fixed contact 211 may be formed integrally with the terminal body 212.

[0022] (2.1.2) Movable Contact The movable contact 22 moves toward and toward a pair of fixed contacts 211, as shown in Figures 1 to 3. More specifically, the movable contact 22 moves toward and toward the pair of fixed contacts 211 in the vertical direction Y2 (second direction), which is perpendicular to the left-right direction Y1 (first direction). The movable contact 22 has a pair of movable contacts 221. The pair of movable contacts 221 are located at both the left and right ends of the left-right direction Y1. In other words, the pair of movable contacts 221 are the ends of the movable contact 22 in the left-right direction Y1. The pair of movable contacts 221 are formed in the vertical direction Y2, facing the pair of fixed contacts 211 with a predetermined distance between them.

[0023] The material of the movable contact 22 is a conductive material such as copper. Alternatively, the material of the movable contact 22 may be a non-magnetic material.

[0024] (2.1.3) The holder 23 has an upper yoke 51, a lower yoke 52, two side plates 53, a spring receiving portion 54, and a contact pressure spring 55.

[0025] (2.1.4) Upper Yoke The upper yoke 51 is formed in the shape of a rectangular parallelepiped, for example, as shown in Figures 1 to 3. The material of the upper yoke 51 is a magnetic material. An example of a magnetic material is electromagnetic soft iron or SPCC (Steel Plate Cold Commercial). The upper yoke 51 is placed on the upper surface of the central part of the movable contactor 22 in the left-right direction Y1. Note that the upper yoke 51 is not limited to being formed in the shape of a rectangular parallelepiped and may be formed in other shapes.

[0026] (2.1.5) Lower Yoke The lower yoke 52, as shown in Figures 1 to 3, is made of a magnetic material and is formed in a U-shape with an open top when viewed from the left-right direction Y1. The lower yoke 52 is positioned below the central part of the movable contact 22 so as to clamp the central part of the movable contact 22 from the front-rear direction Y3.

[0027] (2.1.6) Side Plates The two side plates 53 protrude upward from the spring receiving portion 54, as shown in Figure 3. The material of the two side plates 53 is, for example, metal. The two side plates 53 face each other in the front-rear direction Y3. The upper ends of the two side plates 53 are connected by an upper yoke 51. A movable contact 22 is passed between the upper yoke 51 and the spring receiving portion 54.

[0028] The upper yoke 51, located above the movable contact 22, and the lower yoke 52, located below the movable contact 22, are made of a magnetic material, while the side plate 53 is made of a non-magnetic material. As a result, when the fixed contact 211 and the movable contact 221 come into contact and current flows through the movable contact 22, a magnetic flux is formed around the movable contact 22, passing through the upper yoke 51 and the lower yoke 52 with the movable contact 22 as the center. A magnetic attractive force acts between the upper yoke 51 and the lower yoke 52, and this magnetic attractive force suppresses the electromagnetic repulsive force generated between the fixed contact 211 and the movable contact 221, thereby suppressing a decrease in contact pressure between the fixed contact 211 and the movable contact 221.

[0029] (2.1.7) Spring support portion The spring support portion 54 is located on the side of the movable contact 22 opposite to the pair of fixed contacts 211, as shown in Figures 1 to 3.

[0030] The spring support portion 54 comprises a base portion 541, a positioning portion 542, a protruding portion 543, and a partition wall 544. The partition wall 544 is formed, for example, in a cylindrical shape and extends from the base portion 541 along the axial direction of the movable shaft 24.

[0031] The spring support portion 54 is made of an insulating material. The insulating material is, for example, a synthetic resin. A disc-shaped positioning portion 542 is formed in the center of the upper surface of the base portion 541 of the spring support portion 54. The spring support portion 54 is positioned relative to the contact spring 55 by fitting the positioning portion 542 of the spring support portion 54 into the inner diameter of the lower end side of the contact spring 55.

[0032] (2.1.8) Contact pressure spring The contact pressure spring 55 shown in Figures 1 and 3 is a coil spring. The contact pressure spring 55 is positioned between the spring receiving portion 54 and the movable contact 22 with its expansion and contraction direction oriented in the vertical direction Y2. The contact pressure spring 55 applies an upward spring force to the movable contact 22.

[0033] (2.1.9) Movable shaft As shown in Figures 1 to 3, the movable shaft 24 moves the holder 23 in the vertical direction Y2 (second direction) so that the movable contact 22 moves toward and toward the pair of fixed contacts 211. In other words, the movable shaft 24 moves axially (vertical direction Y2) so that the movable contact 22 moves toward and toward the pair of fixed contacts 211. That is, the movable shaft 24 is connected to the holder 23 and moves in the vertical direction Y2 (second direction) so that the movable contact 22 moves toward and toward the pair of fixed contacts 211. The movable shaft 24 is formed in the shape of a long round rod in the vertical direction Y2. The movable core 34 of the electromagnet device 3 is connected to the lower end of the movable shaft 24. The upper end of the movable shaft 24 is connected to the spring receiving part 54. The movable shaft 24 is fixed to the movable core 34 while being inserted through the fixed core 33, the return spring 36 and the movable core 34.

[0034] (2.1.10) Case The case 25 is box-shaped with an open bottom, as shown in Figures 1 and 3. The material of the case 25 is a heat-resistant material such as ceramic. The case 25 houses a pair of fixed contacts 211 and a movable contact 22. Two through holes 251 are formed on the top surface of the case 25, aligned in the left-right direction Y1. An arc-extinguishing gas such as hydrogen is sealed inside the case 25. The inside space of the case 25 does not have to be sealed and may be connected to the external environment.

[0035] (2.1.11) Connecting Body As shown in Figures 1 and 3, the first end of the connecting body 26 is joined to the opening periphery of the case 25 by brazing. The second end of the connecting body 26 is joined to the first yoke plate 351 of the yoke 35 of the electromagnet device 3 by brazing. In this way, the connecting body 26 connects the case 25 and the yoke 35.

[0036] (2.1.12) Permanent Magnets The two permanent magnets 27 are positioned and fixed between the outer surface of the case 25 and the inner surface of the housing 4, as shown in Figure 1. The two permanent magnets 27 are aligned in the left-right direction Y1. One of the two permanent magnets 27 is positioned to the left of the movable contact 22, and the other is positioned to the right of the movable contact 22.

[0037] The two permanent magnets 27 have opposite poles facing each other. For example, the left permanent magnet 27 has its north pole pointing to the right, and the right permanent magnet 27 has its south pole pointing to the left. The two permanent magnets 27 apply a magnetic field along the left-right direction Y1 between the movable contact 22 and the fixed contact 211.

[0038] (2.1.13) The material of the two bridging sections 28 shown in Figures 2 and 3 is a magnetic material. When viewed from the vertical direction Y2, the shape of each bridging section 28 is U-shaped. One of the two bridging sections 28 is positioned in front of the movable contact 22, and the other is positioned behind the movable contact 22. The two bridging sections 28 are positioned to bridge the gap between the two permanent magnets 27. Furthermore, the two bridging sections 28 hold the two permanent magnets 27. Together with the two permanent magnets 27, the two bridging sections 28 form an annular magnetic circuit.

[0039] (2.2) Electromagnet Device Next, the electromagnet device 3 will be described in detail with reference to the drawings.

[0040] As shown in FIG. 1 and FIG. 3, the electromagnet device 3 drives a movable shaft 24 such that a movable contact 22 is brought into contact with and separated from a pair of fixed contacts 211.

[0041] The electromagnet device 3 comprises a coil 31, a coil bobbin 32, a fixed core 33, a movable core 34, a yoke 35, a return spring 36, a cylindrical member 37, and a bottom wall 38. Further, the electromagnet device 3 includes a pair of coil terminals to which both ends of the coil 31 are connected.

[0042] (2.2.1) Coil As shown in FIG. 1, ends of the coil 31 are respectively connected to a pair of terminal portions provided on a flange 321 of the coil bobbin 32, and the coil 31 is connected to the pair of coil terminals respectively via lead wires connected to the terminal portions. Each coil terminal is formed of a conductive material such as copper, and connected to the corresponding lead wire by soldering or the like.

[0043] (2.2.2) Coil Bobbin As shown in FIG. 1, the coil bobbin 32 includes two flanges 321, 322 and a cylindrical portion 323. The material of the coil bobbin 32 is, for example, synthetic resin. The cylindrical portion 323 is cylindrical. The coil 31 is wound around the cylindrical portion 323. The flange 321 extends outward in a radial direction of the cylindrical portion 323 from an upper end of the cylindrical portion 323. The flange 322 extends outward in the radial direction of the cylindrical portion 323 from a lower end of the cylindrical portion 323.

[0044] (2.2.3) Fixed Core As shown in FIG. 1 and FIG. 3, the fixed core 33 is columnar. The material of the fixed core 33 is a magnetic material. The fixed core 33 is arranged and fixed inside the coil bobbin 32. More specifically, the fixed core 33 is provided in the cylindrical member 37 accommodated in the cylindrical portion 323 of the coil bobbin 32.

[0045] (2.2.4) Movable Iron Core The movable iron core 34 is cylindrical, as shown in FIG. 1 and FIG. 3. The material of the movable iron core 34 is a magnetic material. The movable iron core 34 is disposed in the coil bobbin 32 so as to face the fixed iron core 33 in the vertical direction Y2. More specifically, the movable iron core 34 is accommodated in a cylindrical member 37. The movable iron core 34 is fixed to the movable shaft 24, and moves in the vertical direction Y2 in response to energization of the coil 31. More specifically, when the coil 31 is energized, the movable iron core 34 moves upward. On the other hand, when energization to the coil 31 is cut off, the movable iron core 34 moves downward.

[0046] (2.2.5) Yoke The yoke 35 forms at least a part of a magnetic circuit through which magnetic flux generated by the coil 31 passes when the coil 31 is energized, as shown in FIG. 1 and FIG. 3. The yoke 35 includes a first yoke plate 351, a second yoke plate 352, and two third yoke plates 353. The first yoke plate 351, the second yoke plate 352, and the two third yoke plates 353 are each formed in a plate shape.

[0047] The first yoke plate 351 is disposed between the movable contact 22 and the coil 31. The first yoke plate 351 is in contact with the upper surface of the coil bobbin 32. The shape of the first yoke plate 351 is a rectangular plate shape. An insertion hole 354 is formed in a central portion of the first yoke plate 351. The movable shaft 24 is passed through the insertion hole 354.

[0048] The second yoke plate 352 is in contact with the lower surface of the coil bobbin 32. One of the two third yoke plates 353 extends from the left end of the second yoke plate 352 to the first yoke plate 351. The other of the two third yoke plates 353 extends from the right end of the second yoke plate 352 to the first yoke plate 351.

[0049] (2.2.6) Return Spring The return spring 36 is, for example, a compression coil spring as shown in FIG. 1. A first end of the return spring 36 in the expansion / contraction direction (vertical direction Y2) is in contact with the fixed iron core 33, and a second end thereof is in contact with the movable iron core 34. The return spring 36 applies a spring force to the movable iron core 34 to move the movable iron core 34 downward.

[0050] (2.2.7) Cylindrical Member The cylindrical member 37 is formed in the shape of a bottomed cylinder, as shown in Figure 1. The cylindrical member 37 has a flange portion 371 and a cylindrical portion 372. The cylindrical portion 372 is housed in the cylindrical portion 323 of the coil bobbin 32. The flange portion 371 is formed at the upper end of the cylindrical portion 372. The flange portion 371 is located between the flange portion 321 of the coil bobbin 32 and the first joint plate 351. A fixed core 33 is provided at the upper end of the cylindrical portion 372. A movable core 34 is provided at the lower end of the cylindrical portion 372 of the cylindrical member 37.

[0051] (2.2.8) Bottom wall portion The bottom wall portion 38 holds the second joint plate 352, as shown in Figure 1. The shape of the bottom wall portion 38 is rectangular.

[0052] (2.3) Housing Next, the housing 4 will be described in detail with reference to the drawings.

[0053] As shown in Figures 1 to 3, the housing 4 has a first body 41 and a second body 42.

[0054] (2.3.1) First body The first body 41 is formed in a box shape with an opening on its bottom surface, as shown in Figure 2. The material of the first body 41 is a resin material. The upper surface 411 of the first body 41 has a partition portion 412 that divides the upper surface 411 into two parts, left and right. Each of the upper surface 411 divided by the partition portion 412 has a pair of insertion holes 413 through which the fixing terminals 21 are inserted.

[0055] (2.3.2) Second body The second body 42 is formed in a box shape with an opening on its top surface, as shown in Figure 2. The top surface 411 of the first body 41 has a partition portion 412 that divides the top surface 411 into two parts, left and right. Each of the two parts of the top surface 411 divided by the partition portion 412 has a pair of insertion holes 413 through which the fixing terminals 21 are inserted.

[0056] The second body 42 has a pair of protrusions 421. The pair of protrusions 421 are provided on the left and right side walls. Each of the pair of protrusions 421 has an insertion hole used when fixing the electromagnetic relay 1 to the mounting surface by screwing.

[0057] (2.4) The movable contactor 22 and holder 23 of the contact device 2 will be described in more detail with reference to the detailed diagrams 4 to 6 of the contact device.

[0058] As shown in Figures 4 and 5, the movable contact 22 is positioned to move closer to and further away from the pair of fixed contacts 211 (see Figure 1) in the vertical direction Y2 (second direction). The vertical direction is perpendicular to the horizontal direction Y1 (first direction) in which the pair of fixed contacts 211 (see Figure 1) are aligned. The movable contact 22 is a long, flat plate in the horizontal direction Y1. In plan view, the movable contact 22 has a shape where the length in the horizontal direction Y1 is longer than the width in the front-to-back direction Y3 when viewed from the vertical direction Y2 (for example, an oval shape). The front-to-back direction Y3 is perpendicular to the horizontal direction Y1 and the vertical direction Y2. In the examples in Figures 4 and 5, the plan view shape of the movable contact 22 is exemplified as an oval shape, but it is not limited to an oval shape and may be rectangular, for example.

[0059] The movable contact 22 has two main surfaces A22a and A22b on both sides in the thickness direction (vertical direction Y2) of the movable contact 22. Main surface A22a is the opposing surface that faces the upper yoke 51, which will be described later. Hereafter, main surface A22a may be referred to as opposing surface A22a. Main surface A22b is the main surface on the lower side of the movable contact 22 (opposite the side of the upper yoke 51).

[0060] The holder 23 holds the movable contact 22. As shown in Figures 4 and 5, the holder 23 has an upper yoke 51, a lower yoke 52, two side plates 53, a spring receiving portion 54, and a contact pressure spring 55, as described above. The two side plates 53 and the spring receiving portion 54 constitute the holder body 56. The holder body 56 is fixed to the upper yoke 51 and holds the movable contact 22 and the lower yoke 52 so that they can be displaced relative to each other in the vertical direction Y2.

[0061] The upper yoke 51 constitutes the covering portion. The covering portion is located on the upper side of the holder 23 of the movable contact 22 (i.e., on the side of the pair of fixed terminals 21 (see Figure 1)) and covers a part of the movable contact 22 (for example, the central part in the left-right direction Y1). The upper yoke 51 is, for example, rectangular in shape. In plan view, the upper yoke 51 is a rectangular shape in which the length in the front-back direction Y3 is longer than the length in the left-right direction Y1 when viewed from the up-down direction Y2. The length in the front-back direction Y3 of the upper yoke 51 is longer than the width of the movable contact 22 in the front-back direction.

[0062] The upper yoke 51 has a facing surface A51a that faces the movable contact 22. The facing surface A51a is the main surface on the lower side (movable contact 22 side) of the upper yoke 51. As shown in Figure 6, the facing surface A51a has a central region A51b and a pair of magnetic pole regions A51c. The central region A51b is the region of the facing surface A51a that faces the movable contact 22. The central region A51b is the central region of the facing surface A51a in the front-rear direction Y3. The pair of second magnetic pole regions A51c are regions that face the pair of first magnetic pole regions 522a of the lower yoke 52, which will be described later. The pair of second magnetic pole regions A51c are located on both sides of the central region A51b in the front-rear direction Y3. The pair of second magnetic pole regions A51c are the edges on both sides of the facing surface A51a in the front-rear direction Y3.

[0063] As shown in Figure 6, a convex region A51d is provided on the opposing surface A51a (more specifically, the central region A51b) of the upper yoke 51. The convex region A51d is the part where the upper yoke 51 contacts the opposing surface A22a of the movable contact 22. The plan view shape of the convex region A51d is a rectangle when viewed from the vertical direction Y2. The plan view rectangle shape of the convex region A51d is such that the length in the front-to-back direction Y3 is longer than the length in the left-to-right direction Y1.

[0064] In the example shown in Figure 6, the length of the longitudinal direction Y3 in the convex region A51d is, for example, the same as the length of the longitudinal direction on the opposing surface A22a of the movable contact 22. This makes it possible to make the distance between the point of force AP2 and the fulcrum AP1 on the opposing surface A22a of the movable contact 22 relatively large, as will be described later. Furthermore, the length of the lateral direction Y1 in the convex region A51d is smaller than the length of the lateral direction Y1 on the opposing surface A51a of the upper yoke 51. More specifically, the length of the lateral direction Y1 in the convex region A51d is limited to the center of the lateral direction Y1 on the opposing surface A51a of the upper yoke 51. This reduces the generation of a force moment around the axis of the longitudinal direction Y3 when the upper yoke 51 is struck against the opposing surface A22a of the movable contact 22, as will be described later.

[0065] Since the plan view shape of the convex region A51d is rectangular, it can have a relatively large area compared to the case where the plan view shape of the convex region A51d is circular.

[0066] The height of the convex region A51d (height from the opposing surface A51a of the upper yoke 51) is such that, as described later, when the opposing surface A51a of the upper yoke 51 is inclined with respect to the opposing surface A22a of the movable contact 22 and the convex region A51d contacts the opposing surface A22a of the movable contact 22, the portion of the opposing surface A51a of the upper yoke 51 other than the convex region A51d does not come into contact with the opposing surface A22a of the movable contact 22. Furthermore, the height of the convex region A51d (height from the opposing surface A51a of the upper yoke 51) is such that, as described later, when the opposing surface A51a of the upper yoke 51 is inclined with respect to the opposing surface A22a of the movable contact 22 and the convex region A51d contacts the opposing surface A22a of the movable contact 22, the opposing surface A51a of the upper yoke 51 does not come into contact with the pair of first magnetic pole regions A522a of the lower yoke 52.

[0067] Since the convex region A51d is a quadrilateral in plan view, it has four edges along the four sides of the quadrilateral in plan view (i.e., a pair of long side edges A51e and A51f along the front-to-back direction, and short side edges A51g and A51h along the left-to-right direction).

[0068] The lower yoke 52 is fixed to the main surface A22b of the movable contact 22 on the lower side of the movable contact 22 (opposite side from the upper yoke 51 side). The lower yoke 52 has a bottom portion A511 and a pair of side wall portions A522 (see Figure 5).

[0069] The bottom portion A511 is fixed to the main surface A22b of the movable contact 22. The bottom portion A511 is, for example, a rectangular flat plate when viewed from the vertical direction Y2. Multiple protrusions A521p are provided on the lower surface of the bottom portion A511 (the main surface opposite to the upper yoke 51 side) to position the upper end of the contact pressure spring 55.

[0070] The pair of side wall portions A522 protrude upward (towards the upper yoke 51) from both ends in the width direction (front-rear direction Y3) of the bottom portion A511. The pair of side wall portions A522 cover a portion of the sides of the movable contact 22 in the width direction (front-rear direction Y3) (the central part in the left-right direction Y1). The upper end surfaces of the pair of side wall portions A522 constitute a pair of second magnetic pole regions A51c. The pair of second magnetic pole regions A51c are arranged on both sides of the movable contact 22 in the front-rear direction Y3.

[0071] The spring support portion 54 is connected (fixed) to the upper yoke 51 with a housing space between them, and holds the movable contact 22, the lower yoke 52, and the contact pressure spring 55 in the housing space between the upper yoke 51 and the spring support portion 54. The spring support portion 54 is located on the lower side of the lower yoke 52 (i.e., on the opposite side from the upper yoke 51). As shown in Figure 5, the spring support portion 54 comprises a base portion 541, a positioning portion 542, a protruding portion 543 (see Figure 1), and a partition wall 544. The base portion 541, the positioning portion 542, the protruding portion 543, and the partition wall 544 have already been described in "(2) Components of the electromagnetic relay," so their description here is omitted.

[0072] The two side plates 53 protrude upward (towards the upper yoke 51) from the side surfaces on both sides of the spring receiving portion 54 in the front-rear direction Y3 (see Figure 5). The upper parts of the two side plates 53 are connected (fixed) to both end faces of the upper yoke 51 in the front-rear direction Y3 (see Figure 4).

[0073] The contact pressure spring 55 is positioned between the lower yoke 52 and the spring receiving portion 54 in a compressed state in the vertical direction Y2. The compression spring 55 biases the lower yoke 52 and the movable contact 22 toward the upper yoke 51.

[0074] (3) Operation of the electromagnetic relay Next, the operation of the electromagnetic relay 1 according to Embodiment 1 will be described with reference to Figures 1 and 3.

[0075] First, when the movable shaft 24 is displaced upward by the electromagnet device 3, the holder 23 connected to the movable shaft 24 is displaced upward along with the displacement of the movable shaft 24. As the holder 23 is displaced, the movable contact 22 moves upward. Then, the movable contact 22 comes into contact with the pair of fixed contacts 211, and electrical conductivity is established between the contacts.

[0076] First, in the electromagnet device 3, when no current flows through the coil 31, the movable core 34 moves downward due to the biasing force of the return spring 36. As the movable core 34 moves, the movable shaft 24 also moves downward. When the movable shaft 24 moves downward, the holder 23 also moves downward. The movable contact 22 moves downward together with the holder 23. When the movable contact 22 is moving downward, the movable contact 221 is separated from the fixed contact 211.

[0077] Next, in the electromagnet device 3, when the coil 31 is energized, the movable core 34 is attracted to the fixed core 33 and moves upward. As the movable core 34 moves, the movable shaft 24 also moves upward. As the movable shaft 24 moves upward, the holder 23 also moves upward. The movable contact 22 moves upward together with the holder 23. When the movable contact 22 is moving upward, the movable contact 221 comes into contact with the fixed contact 211, and electrical conductivity is established between the fixed contact 211 and the movable contact 221.

[0078] Subsequently, when the power supply to the coil 31 is cut off, the movable core 34 moves downward due to the biasing force of the return spring 36, and the movable shaft 24 and holder 23 also move downward along with the movement of the movable core 34. Along with the above movement of the holder 23, the movable contact 22 also moves downward, and the fixed contact 211 and the movable contact 221 are separated.

[0079] (4) Detailed Operation of Electromagnetic Relay The operation of electromagnetic relay 1 will be explained in detail with reference to Figures 1 and 6.

[0080] As described in "(3) Operation of the electromagnetic relay" above, when the movable shaft 24 is displaced upward by the electromagnet device 3 and the movable contact 22 comes into contact with the pair of fixed contacts 211, electrical conductivity is established between the pair of fixed contacts 211 and the movable contact 22. At this time, the arc generated when the fixed contacts 211 and the movable contact 22 come into contact may melt the contact material, causing the movable contact 22 to become fixed to the pair of fixed contacts 211. Then, the movable shaft 24 is further displaced upward by a certain distance AL1 by the electromagnet device 3 (see Figure 6). The certain distance AL1 is the distance between the opposing surface A51a of the upper yoke 51 and the opposing surface A22a of the movable contact 22. At this time, of the holder 23, the movable contact 22 does not displace upward because it is in contact with the pair of fixed contacts 211, and only the upper yoke 51 and the holder body 56 are displaced upward by compressing the contact pressure spring 55 in the vertical direction. This displacement causes the upper yoke 51 to be positioned at a certain distance AL1 from the opposing surface A22a of the movable contact 22 (see Figure 6).

[0081] Then, as described in "(3) Operation of the electromagnetic relay" above, when the power to the coil 31 is cut off, the movable contact 22 moves downward as the movable shaft 24 and holder 23 move downward, and the contact between the pair of fixed contacts 211 and the movable contact 22 is separated. More specifically, when the movable shaft 24 moves downward by a certain distance AL1, the upper yoke 51 and the holder body 56 of the holder 23 move downward first.

[0082] At this time, the movable shaft 24 moves downward due to the biasing force of the return spring 36, and the upper yoke 51 is struck against the opposing surface A22a of the movable contact 22 by the biasing force of the return spring 36. At this time, due to the influence of the contact pressure spring 55, the opposing surface A51a of the upper yoke 51 is struck against the opposing surface A22a of the movable contact 22 while being inclined relative to the opposing surface A22a of the movable contact 22. For example, the opposing surface A51a of the upper yoke 51 is struck against the opposing surface A22a of the movable contact 22 while being inclined in the front-rear direction relative to the opposing surface A22a of the movable contact 22.

[0083] Therefore, one of the short edges A51g and A51h on both sides of the convex region A51d of the upper yoke 51 (for example, short edge 51h) instantaneously presses with a pressing force AF1 against one edge (point of force application AP2) in the front-rear direction Y3 on the opposing surface A22a of the movable contact 22 before the other short edge 51g. This pressing force AF1 generates a moment of force AM1 around the pivot point AP1 (i.e., around the axis extending in the left-right direction Y1) on the movable contact 22.

[0084] The moment of force AM1 is the product of the distance between the fulcrum AP1 and the point of application of force AP2 and the pressing force AF1. In other words, the greater the distance between the fulcrum AP1 and the point of application of force AP2, the greater the moment of force AM1. The fulcrum AP1 is the position furthest from the point of application of force AP2 in the front-rear direction Y3 within the contact range with the fixed contact 211 on the opposing surface A22a of the movable contactor 22. In the example in Figure 6, it is assumed that the opposing surface A22a of the movable contactor 22 contacts the fixed contact 211 over the entire length of the front-rear direction Y3 on the opposing surface A22a. Therefore, the fulcrum AP1 is the position at the outermost end of the opposing surface A22a, opposite to the side of the point of application of force AP2.

[0085] Furthermore, it is assumed that the opposing surface A22a of the movable contact 22 is fixed to the fixed contact 211 by continuously contacting it. The movable contact 22 is attracted to the fixed contact 211 by the fixing force AF2. It is assumed that the fixing force AF2 is directed upward (towards the fixed contact 211) at the central position AP3 in the front-rear direction Y3 within the contact range of the opposing surface A22a of the movable contact 22 (i.e., the central position in the front-rear direction Y3 on the opposing surface A22a).

[0086] In this electromagnetic relay 1, the movable contact 22 is fixed to the fixed contact 211 by a fixing force AF2 when the terminals of the movable contact 22 and the fixed contact 211 come into contact. However, as described above, when the upper yoke 51 is struck against the movable contact 22, the upper yoke 51 generates a relatively large moment of force AM1 on the movable contact 22. This moment of force AM1 then efficiently pulls the movable contact 22 away from the fixed contact 211.

[0087] The convex region A51d is limited to the area within the range of the opposing surface A51a of the upper yoke 51. More specifically, since the upper yoke 51 is positioned in the center of the left-right direction Y1 on the opposing surface A22a of the movable contact 22, the convex region A51d is limited to the center of the left-right direction on the opposing surface A22a of the movable contact 22. For this reason, as described above, when the upper yoke 51 is struck against the opposing surface A22a of the movable contact 22, the upper yoke 51 generates almost no force moment around the axis extending in the front-rear direction Y3 on the movable contact 22. For this reason, the bias between the peeling force when peeling the movable contact 22 from the right fixed contact 211 and the peeling force when peeling the movable contact 22 from the left fixed contact 211 can be reduced. As a result, as described above, when the upper yoke 51 is struck against the opposing surface A22a of the movable contact 22, the upper yoke 51 effectively separates the movable contact 22 from the pair of fixed contacts 211.

[0088] As described above, when the movable contact 22 is pulled away from the pair of fixed contacts 211, the opposing surface A22a of the movable contact 22 becomes parallel to the opposing surface A51a of the upper yoke 51 and makes surface contact with the convex region A51d of the upper yoke 51. In this state of surface contact, the movable contact 22 is pushed down by the upper yoke 51 and moves downward. The convex region A51d is a rectangle in plan view and therefore has a relatively large area. For this reason, even when the convex region A51d makes surface contact with the opposing surface A22a of the movable contact 22 and presses, the pressure per unit area is small, so the opposing surface A22a of the movable contact 22 is hardly indented (i.e., hardly deformed) by the convex region A51d. As a result, even when the upper yoke 51 makes surface contact with the opposing surface A22a of the movable contact 22 and presses, the opposing surface A22a of the movable contact 22 hardly deforms over time. Therefore, the change in the amount of Over-Travel (OT) over time due to the deformation of the movable contact 22 can be reduced. This reduces the decrease in peeling ability due to the change in the amount of OT over time. In other words, the peeling ability can be improved.

[0089] In Embodiment 1, when the convex region A51d of the upper yoke 51 is in surface contact with the opposing surface A22a of the movable contactor 22, the opposing surface A51a of the upper yoke 51 does not come into contact with the pair of first magnetic pole regions A522a of the lower yoke 52.

[0090] (5) Compared to the contact device 2 of comparative example embodiment 1, we consider a modified contact device (hereinafter simply referred to as "modified device") which is configured similarly except that the plan view shape of the convex region A51d is circular.

[0091] In the modified example, since the convex region A51d is circular in plan view, when the convex region A51d is formed on the opposing surface A51a of the upper yoke 51 (i.e., the opposing surface that is longer in the front-rear direction Y3 than in the left-right direction Y1), the convex region A51d reaches both ends in the left-right direction Y1 on the opposing surface A51a first, and therefore cannot extend to both ends in the front-rear direction Y3 on the opposing surface A51a. For this reason, the distance between the fulcrum and the point of application of the force moment AM1 in the modified example is shorter than the distance between the fulcrum and the point of application of the force moment AM1 in Embodiment 1. For this reason, in the modified example, the force moment AM1 is smaller compared to Embodiment 1, and the movable contact 22 cannot be effectively pulled away from the pair of fixed contacts 211.

[0092] (6) The contact device 2 according to the first embodiment comprises a pair of fixed contacts 211, a movable contact 22, a holder 23, and a movable shaft 24. The pair of fixed contacts 211 are aligned in the left-right direction Y1. The movable contact 22 moves toward and toward the pair of fixed contacts 211 in the up-down direction Y2, which is perpendicular to the left-right direction Y1. The holder 23 holds the movable contact 22. The movable shaft 24 moves the holder 23 in the up-down direction Y2 so that the movable contact 22 moves toward and toward the pair of fixed contacts 211. The holder 23 has an upper yoke 51. The upper yoke 51 is positioned on the side of the pair of fixed contacts 211 on the movable contact 22 and covers a part of the movable contact 22. The first opposing surface (for example, opposing surface A51a) of the opposing surfaces A22a of the movable contactor 22 with the upper yoke 51 and A51a of the opposing surfaces A51a of the upper yoke 51 with the movable contactor 22 is provided with a convex region A51d that contacts and separates from the remaining opposing surface, the second opposing surface (for example, opposing surface A22a). The convex region A51d has a rectangular shape when viewed from the vertical direction Y2 in plan view.

[0093] With this configuration, since the convex region A51d provided on the first opposing surface (for example, opposing surface A51a) is rectangular in shape, the contact area between the convex region A51d and the second opposing surface (opposing surface A22a) can be increased compared to the case where the convex region A51d is circular. Therefore, the gradual indentation of the second opposing surface (for example, opposing surface A22a) over time due to the convex region A51d pressing against it can be reduced. As a result, the peeling performance when peeling the movable contact 22 from the pair of fixed contacts 211 can be improved.

[0094] Furthermore, because the convex region A51d is rectangular in shape, when the convex region A51d strikes the second opposing surface (for example, the opposing surface A22a), it can effectively generate a moment of force AM1 around an axis extending in the front-rear direction Y3, which is perpendicular to the left-right direction Y1 and the up-down direction Y2, on the movable contact 22. This allows the movable contact 22 to be effectively separated from the pair of fixed contacts 211. In other words, the separation performance when separating the movable contact 22 from the pair of fixed contacts 211 can be further improved.

[0095] Furthermore, in the contact device 2 according to Embodiment 1, the holder 23 includes an upper yoke 51, a lower yoke 52, a contact pressure spring 55, and a holder body 56. The upper yoke 51 constitutes a covering portion. The lower yoke 52 is fixed to the main surface A22b of the movable contact 22 on the side opposite to the upper yoke 51. The contact pressure spring 55 biases the lower yoke 52 toward the upper yoke 51. The holder body 56 is fixed to the upper yoke 51 and holds the movable contact 22 and the lower yoke 52 so that they can be displaced relative to each other in the vertical direction Y2.

[0096] With this configuration, even when the covering portion is made up of an upper yoke 51, the peeling performance when peeling the movable contact 22 from the pair of fixed contacts 211 can be improved.

[0097] Furthermore, in the contact device 2 according to Embodiment 1, the height of the convex region A51d from the first opposing surface (for example, opposing surface A51a) is such that when the opposing surface A51a of the upper yoke 51 is inclined with respect to the opposing surface A22a of the movable contactor 22 and the convex region A51d comes into contact with the second opposing surface (for example, opposing surface A22a), the portion of the first opposing surface (for example, opposing surface A51a) other than the convex region A51d does not come into contact with the second opposing surface (opposing surface A22a).

[0098] With this configuration, when the convex region A51d contacts the second opposing surface (for example, the opposing surface A22a) while the opposing surface A51a of the upper yoke 51 is inclined with respect to the opposing surface A22a of the movable contactor 22, a force moment AM1 around the axis extending in the vertical direction Y2 can be effectively generated.

[0099] Furthermore, in the contact device 2 according to Embodiment 1, the length of the left-right direction Y1 in the convex region A51d is smaller than the length of the left-right direction Y1 in the first opposing surface (for example, opposing surface A51a).

[0100] This configuration reduces the generation of force moments around an axis extending in the front-rear direction Y3, which is perpendicular to the left-right direction Y1 and the up-down direction Y2. Therefore, it is possible to reduce the imbalance between the force pulling the movable contact 22 away from one of the pair of fixed contacts 211 and the force pulling the movable contact 22 away from the other of the pair of fixed contacts 211. As a result, the movable contact 22 can be effectively pulled away from the pair of fixed contacts 211.

[0101] Furthermore, in the contact device 2 according to Embodiment 1, the rectangular shape of the convex region A51d is a rectangle in which the length of the front-to-back direction Y3, which is perpendicular to the left-to-right direction Y1 and the up-to-down direction Y2, is longer than the length of the left-to-right direction Y1.

[0102] This configuration allows for an even greater distance between the fulcrum AP1 and the point of application AP2 in the force moment AM1 described above. Consequently, the force moment AM1 can be made even larger. As a result, the peeling performance when separating the movable contact 22 from the pair of fixed contacts 211 can be further improved.

[0103] Furthermore, in the contact device 2 according to Embodiment 1, the convex region A51d is provided on the opposing surface A51a of the upper yoke 51. The length of the front-rear direction Y3 in the convex region A51d, which is perpendicular to the left-right direction Y1 and the up-down direction Y2, is the same as the length of the front-rear direction Y3 of the opposing surface A22a of the movable contact 22.

[0104] This configuration allows for an even greater distance between the fulcrum AP1 and the point of application AP2 in the force moment AM1 described above. Consequently, the force moment AM1 can be made even larger. As a result, the peeling performance when separating the movable contact 22 from the pair of fixed contacts 211 can be further improved.

[0105] Furthermore, in the contact device 2 according to Embodiment 1, in the front-rear direction Y3 which is perpendicular to the left-right direction Y1 and the up-down direction Y2, the convex region A51d contacts the second opposing surface (opposing surface A22a) with the opposing surface A51a of the upper yoke 51 inclined with respect to the opposing surface A22a of the movable contact element 22.

[0106] With this configuration, when the convex region A51d strikes the second opposing surface (opposing surface A22a), a moment of force AM1 can be generated in the movable contact 22 around an axis extending in the front-rear direction Y3. This improves the peeling performance when peeling the movable contact 22 from the pair of fixed contacts 211.

[0107] Furthermore, the electromagnetic relay 1 according to Embodiment 1 comprises a contact device 2 and an electromagnet device 3. The electromagnet device 3 drives a movable shaft 24 so that a movable contact 22 moves toward and away from a pair of fixed contacts 211.

[0108] This configuration makes it possible to provide an electromagnetic relay 1 that achieves the above-mentioned effects of the contact device 2.

[0109] (7) Modifications Below, modifications of Embodiment 1 will be described. The following modifications may be carried out in combination.

[0110] (7-1) Modification 1 In the contact device 2 of the electromagnetic relay 1 according to Embodiment 1, the pair of movable contacts 221 are part of the movable contact 22 and are provided integrally with the movable contact 22. However, as a modification of Embodiment 1, the pair of movable contacts may be provided separately from the movable contact 22. In such a contact device 2 as well, the movable contact provided separately from the movable contact 22 moves integrally with the movable contact 22 as the movable shaft 24 moves, and the movable contact moves toward and away from the fixed contact 211.

[0111] The contact device 2 and electromagnetic relay 1 according to the above modified example also provide the same effects as the contact device 2 and electromagnetic relay 1 according to the embodiment.

[0112] (7-2) Modification 2 In Embodiment 1, the convex region A51d is provided on the opposing surface A51a of the upper yoke 51 as an example. However, the convex region A51d may also be provided on the opposing surface A22a of the movable contact 22. In this case as well, the same effects as in Embodiment 1 are achieved. From Embodiment 1 and this Modification 2, the convex region A51d only needs to be provided on one of the opposing surfaces A22a of the movable contact 22 and A51a of the upper yoke 51.

[0113] (Embodiment 2) The contact device 2 according to Embodiment 2 differs from the contact device 2 according to Embodiment 1 in that, as shown in Figure 8, a pair of convex regions A522b and A522c are provided in a pair of first magnetic pole regions A522a, A522a of the lower yoke 52. Regarding the contact device 2 according to Embodiment 2, components similar to those in the contact device 2 according to Embodiment 1 are denoted by the same reference numerals and their descriptions are omitted.

[0114] (1) The contact device 2 according to the second embodiment of the configuration includes a pair of convex regions A522b and A522c provided in a pair of first magnetic pole regions A522a and A522a of the lower yoke 52, as shown in Figure 8, instead of the convex region A51d of the first embodiment.

[0115] The planar shape of each of the pair of convex regions A522b and A522c is, for example, a rectangle when viewed from above. In the example of Figure 8, the length Y3 in the front-to-back direction in the convex regions A522b and A522c is, for example, the same as the length Y3 in the front-to-back direction in the first magnetic pole region A522a. Also, the length Y1 in the left-to-right direction in the convex regions A522b and A522c is smaller than the length Y1 in the left-to-right direction in the first magnetic pole region A522a. More specifically, the length Y1 in the left-to-right direction in the convex regions A522b and A522c is limited to the central part of the length Y1 in the left-to-right direction in the first magnetic pole region A522a. The height of the pair of first pole regions A522a, A522a in the convex regions A522b, A522c from the pair of first pole regions A522a, A522a is such that, when the opposing surface A51a of the upper yoke 51 is inclined with respect to the pair of first pole regions A522a, A522a of the lower yoke 52, and one of the pair of convex regions A522b, A522c contacts one of the pair of second pole regions A51c of the upper yoke 51 (the pole region opposite to the pair of first pole regions A522a, A522a), the portion of the pair of first pole regions A522a, A522a other than the pair of convex regions A522b, A522c does not contact the pair of second pole regions A51c of the opposing surface A51a of the upper yoke 51.

[0116] In Embodiment 2, the convex region A51d of Embodiment 1 is not provided on the opposing surface A51a of the upper yoke 51; therefore, the opposing surface A51a is a flat surface.

[0117] In Embodiment 2, the pair of first pole regions A522a, A522a of the lower yoke 52 are positioned above the opposing surface A22a of the movable contact 22 in the vertical direction Y2. As a result, when the pair of convex regions A522b, A522c of the lower yoke 52 are in contact with the opposing surface A51a of the upper yoke 51, the opposing surface A51a of the upper yoke 51 does not come into contact with the opposing surface A22a of the movable contact 22.

[0118] (2) Operation Next, the operation of the electromagnetic relay 1 according to Embodiment 2 will be described with reference to Figures 1 and 9.

[0119] The basic operation of the electromagnetic relay 1 according to Embodiment 2 is the same as that described in "(3) Operation of the electromagnetic relay" of Embodiment 1. The following description details the operation of the electromagnetic relay 1 of Embodiment 2.

[0120] In Embodiment 2, as in Embodiment 1, with the movable contact 22 in contact with the pair of fixed contacts 211, the upper yoke 51 moves a certain distance AL2 upward from the opposing surface A22a of the movable contact 22 (see Figure 9). Then, as in Embodiment 1, when the power supply to the coil 31 is cut off in this state, the movable shaft 24 moves downward due to the biasing force of the return spring 36, and the upper yoke 51 and holder 23 move downward along with this movement.

[0121] At this time, the upper yoke 51 is struck against the pair of convex regions A522b and A522c of the lower yoke 52 by the biasing force of the return spring 36. At this time, due to the influence of the contact pressure spring 55, the opposing surface A51a of the upper yoke 51 is struck against the pair of convex regions A522b and A522c of the lower yoke 52 while being inclined relative to the pair of convex regions A522b and A522c. For example, the opposing surface A51a of the upper yoke 51 is struck against the pair of convex regions A522b and A522c while being inclined in the front-rear direction relative to the pair of convex regions A522b and A522c.

[0122] Therefore, one of the outer edges A522d and A522e of the pair of convex regions A522b and A522c of the lower yoke 52 in the front-rear direction Y3 (for example, A522e) contacts the opposing surface A51a of the upper yoke 51 before the other edge A522d, and is instantaneously pressed by a pressing force AF3 from the upper yoke 51. At this time, one edge A522e becomes the point of force AP4 that receives the pressing force AF3 from the upper yoke 51. This pressing force AF3 generates a moment of force AM2 in the lower yoke 52 around the fulcrum AP5 (i.e., around the axis extending in the left-right direction Y1).

[0123] The force moment AM2 has a magnitude equal to the product of the distance between the fulcrum AP5 and the point of application AP4 and the pressing force AF3. That is, the greater the distance between the fulcrum AP5 and the point of application AP4, the greater the force moment AM2. In Embodiment 2, since the pair of convex regions A522b and A522c are arranged on both sides of the movable contact 22 in the front-rear direction Y3, the distance between the point of application AP4 and the fulcrum AP5 is relatively large. For this reason, the force moment AM2 is relatively large.

[0124] The pivot point AP5 is the position furthest from the point of force AP4 in the front-rear direction Y3 within the contact range with the fixed contact 211 on the opposing surface A22a of the movable contact 22. In the example in Figure 9, it is assumed that the opposing surface A22a of the movable contact 22 contacts the fixed contact 211 over the entire length of the front-rear direction Y3 on the opposing surface A22a. Therefore, the pivot point AP5 is the position at the outermost end of the opposing surface A22a, opposite to the point of force AP4.

[0125] Furthermore, similar to the first embodiment, the opposing surface A22a of the movable contact 22 is fixed by continuous contact with the fixed contact 211. The movable contact 22 is attracted to the fixed contact 211 by its fixation with the fixed contact 211 (fixing force AF6). It is assumed that the fixing force AF6 is directed upward (towards the fixed contact 211) at the central position AP6 in the front-rear direction Y3 within the contact range of the opposing surface A22a of the movable contact 22 (i.e., the central position in the front-rear direction Y3 on the opposing surface A22a).

[0126] In this electromagnetic relay 1, as in the first embodiment, the movable contact 22 is fixed to the fixed contact 211 by a fixing force AF6 when the terminals of the movable contact 22 come into contact with the fixed contact 211. However, as described above, when the upper yoke 51 is struck against the pair of convex regions A522b and A522c of the lower yoke 52, a relatively large moment of force AM2 is generated in the movable contact 22 by the pair of convex regions A522b and A522c. This moment of force AM2 efficiently detaches the movable contact 22 from the pair of fixed contacts 211.

[0127] The pair of convex regions A522b and A522c are each limited to the range of the pair of first magnetic pole regions A522a, A522a of the lower yoke 52 (more specifically, the central part in the left-right direction Y1 within the pair of first magnetic pole regions A522a, A522a). Therefore, as described above, when the upper yoke 51 is struck against the opposing surface A22a of the movable contact 22, the upper yoke 51 generates almost no force moment around the axis extending in the front-rear direction Y3 on the movable contact 22. Therefore, the bias between the peeling force when peeling the movable contact 22 from the right fixed contact 211 and the peeling force when peeling the movable contact 22 from the left fixed contact 211 can be reduced. As a result, as described above, when the upper yoke 51 strikes the pair of convex regions A522b and A522c of the lower yoke 52, the upper yoke 51 effectively detaches the movable contact 22 from the pair of fixed contacts 211.

[0128] As described above, when the movable contact 22 is pulled away from the pair of fixed contacts 211, the pair of convex regions A522b and A522c of the lower yoke 52 become parallel to the opposing surface A51a of the upper yoke 51 and make surface contact with the opposing surface A51a. In this state of surface contact, the lower yoke 52 is pushed down by the upper yoke 51 and moves downward. Both the upper yoke 51 and the lower yoke 52 are made of magnetic material (i.e., a relatively hard material). Therefore, even when the pair of convex regions A522b and A522c of the lower yoke 52 make surface contact with the opposing surface A51a of the upper yoke 51 and press against it, the opposing surface A22a of the movable contact 22 and the pair of convex regions A522b and A522c of the lower yoke 52 hardly dent (i.e., hardly deform). As a result, even when the upper yoke 51 presses against the pair of convex regions A522b and A522c of the lower yoke 52 in surface contact, the pair of convex regions A522b and A522c of the upper yoke 51 and lower yoke 52 do not deform over time. Therefore, the change in the amount of OT (Over-Travel) over time due to the deformation of the movable contactor 22 can be reduced. This reduces the decrease in peeling ability due to the change in the amount of OT over time. In other words, the peeling ability can be improved.

[0129] In Embodiment 2, when the opposing surface A51a of the upper yoke 51 is in surface contact with the pair of convex regions A522b and A522c of the lower yoke 52, the opposing surface A51a of the upper yoke 51 does not come into contact with the opposing surface A22a of the movable contactor 22.

[0130] (3) The contact device 2 according to the second embodiment comprises a pair of fixed contacts 211, a movable contact 22, a holder 23, and a movable shaft 24. The pair of fixed contacts 211 are aligned in the left-right direction Y1. The movable contact 22 moves toward and toward the pair of fixed contacts 211 in the up-down direction Y2, which is perpendicular to the left-right direction Y1. The holder 23 holds the movable contact 22. The movable shaft 24 moves the holder 23 in the up-down direction Y2 so that the movable contact 22 moves toward and toward the pair of fixed contacts 211. The holder 23 has an upper yoke 51, a lower yoke 52, a contact pressure spring 55, and a holder body 56. The upper yoke 51 is located above the movable contact 22. The lower yoke 52 is fixed to the lower surface of the movable contact 22. The contact pressure spring 55 biases the lower yoke 52 toward the upper yoke 51. The holder body 56 is fixed to the upper yoke 51 and holds the movable contact 22 and the lower yoke 52 so that they can be displaced relative to each other in the vertical direction Y2. The lower yoke 52 has a pair of first magnetic pole regions A522a. The pair of first magnetic pole regions A522a are arranged on both sides of the movable contact 22 in the front-rear direction Y3, which is perpendicular to the left-right direction Y1 and the up-down direction Y2. The opposing surface A51a of the upper yoke 51 that faces the movable contact 22 has a pair of second magnetic pole regions A51c. The pair of second magnetic pole regions A51c face the pair of first magnetic pole regions A522a. In one of the pair of first pole regions A522a and the pair of second pole regions A51c (for example, the first pole region A522a), a pair of convex regions A522b and A522c are provided that contact and separate from the other pair of pole regions (the pair of second pole regions A51c).

[0131] In this configuration, each pair of convex regions A51d is provided in one of the pair of first magnetic pole regions A522a of the lower yoke 52 and one of the pair of second magnetic pole regions A51c of the upper yoke 51 (for example, A522a). The lower yoke 52 and upper yoke 51 are usually formed of a magnetic material (i.e., a material that is relatively harder than the material of the movable contact 22 (for example, copper, etc.)). Therefore, even if the pair of convex regions A522b and A522c press against the other pair of magnetic pole regions (for example, the pair of second magnetic pole regions A51c), the gradual recession of the other pair of magnetic pole regions (for example, the pair of second magnetic pole regions A51c) over time can be reduced. As a result, the peeling performance when peeling the movable contact 22 from the pair of fixed contacts 211 can be improved.

[0132] Furthermore, the pair of convex regions A51d are provided in one of the pair of first magnetic pole regions A522a of the lower yoke 52 and the pair of second magnetic pole regions A51c of the upper yoke 51 (for example, the pair of first magnetic pole regions A522a). Therefore, when the pair of convex regions A51d strike the other pair of magnetic pole regions (for example, the pair of second magnetic pole regions A51c), a force moment AM2 around the axis extending in the front-rear direction Y3 can be effectively generated in the movable contact 22. This allows the movable contact 22 to be effectively separated from the pair of fixed contacts 211. In other words, the separation performance when separating the movable contact 22 from the pair of fixed contacts 211 can be further improved.

[0133] Furthermore, in the contact device 2 according to Embodiment 2, the height of one pair of magnetic pole regions (for example, a pair of first magnetic pole regions A522a) in the pair of convex regions A522b and A522c is such that when the opposing surface A51a of the upper yoke 51 is inclined with respect to the pair of first magnetic pole regions A522a of the lower yoke 52, and one of the pair of convex regions A522b and A522c comes into contact with one of the other pair of magnetic pole regions (for example, a pair of second magnetic pole regions A51c), the portion of one pair of magnetic pole regions (for example, a pair of first magnetic pole regions A522a) other than the pair of convex regions A522b and A522c does not come into contact with the other pair of magnetic pole regions (for example, a pair of second magnetic pole regions A51c).

[0134] With this configuration, when the opposing surface A51a of the upper yoke 51 is inclined with respect to the pair of first magnetic pole regions A522a of the lower yoke 52, and the pair of convex regions A522b and A522c come into contact with the other pair of magnetic pole regions (the pair of second magnetic pole regions A51c), a force moment AM2 around the axis extending in the vertical direction Y2 can be effectively generated.

[0135] Furthermore, in the contact device 2 according to Embodiment 2, the length of the left-right direction Y1 in the pair of convex regions A522b and A522c is smaller than the length of the left-right direction Y1 in one of the pair of first magnetic pole regions A522a.

[0136] This configuration reduces the generation of a force moment AM2 around an axis extending in the front-rear direction Y3, which is perpendicular to the left-right direction Y1 and the up-down direction Y2. Therefore, it is possible to reduce the imbalance between the force that pulls the movable contact 22 away from one of the pair of fixed contacts 211 and the force that pulls the movable contact 22 away from the other of the pair of fixed contacts 211. As a result, the movable contact 22 can be effectively pulled away from the pair of fixed contacts 211.

[0137] Furthermore, in the contact device 2 according to Embodiment 2, in the front-rear direction Y3 which is perpendicular to the left-right direction Y1 and the up-down direction Y2, the opposing surface A51a of the upper yoke 51 is inclined relative to the pair of first magnetic pole regions A522a, and one of the pair of convex regions A522b and A522c contacts one of the other pair of magnetic pole regions (the pair of second magnetic pole regions A51c).

[0138] With this configuration, when the convex regions A522b and A522c strike the other pair of magnetic pole regions (a pair of second magnetic pole regions A51c), a moment of force AM2 can be generated in the movable contact 22 around an axis extending in the front-rear direction Y3. This improves the peeling performance when separating the movable contact 22 from the pair of fixed contacts 211.

[0139] (4) Modifications Below, modifications of Embodiment 2 will be described.

[0140] In Embodiment 2, the pair of convex regions A522b and A522c are provided in a pair of first magnetic pole regions A522a and A522a of the lower yoke 52. However, the pair of convex regions A522b and A522c may also be provided in a pair of second magnetic pole regions on the opposing surface A51a of the upper yoke 51 that are opposite to the pair of first magnetic pole regions A522a and A522a of the lower yoke 52. In this case as well, the same effects as in Embodiment 2 are achieved. From Embodiment 2 and the above modified example, the pair of convex regions A522b and A522c may be provided in one of the pair of first magnetic pole regions A522a and A522a of the lower yoke 52 and one of the pair of second magnetic pole regions on the opposing surface A51a of the upper yoke 51.

[0141] (Embodiment 3) The contact device 2 according to Embodiment 3 differs from the contact device 2 according to Embodiment 1 in that the holder 23 does not include the upper yoke 51 and the lower yoke 52, as shown in Figures 10 and 11. Regarding the contact device 2 according to Embodiment 3, components similar to those in the contact device 2 according to Embodiment 1 are denoted by the same reference numerals and their descriptions are omitted.

[0142] (1) The contact device 2 according to the configuration embodiment 3 includes a holder A50 which does not include the upper yoke 51 and lower yoke 52, as shown in Figures 10 and 11, instead of the holder 23 of embodiment 1.

[0143] More specifically, the holder A50 comprises a lower holder portion A51, an upper holder portion A52, and a contact pressure spring A53.

[0144] The lower holder portion A51 is positioned below the movable contact 22 and is connected to the upper holder portion A52 with a housing space between them. The movable contact 22 and the contact pressure spring 53 are held in this housing space between the upper holder portion A52 and the lower holder portion A51. The lower holder portion A51 is made of, for example, resin.

[0145] The lower holder portion A51 has a bottom portion A511, a spring receiving portion A512, two side wall portions A513, and a connecting portion A514.

[0146] The bottom portion A511 is, for example, a rectangular flat plate. The bottom portion A511 has main surfaces A511a and A511b on both sides in the thickness direction (vertical direction Y2). Main surface A511a is the main surface on the upper holder portion A52 side. Main surface A511b is the main surface on the opposite side from the upper holder portion A52 side.

[0147] The spring support portion A512 positions the lower end of the contact pressure spring A53. The spring support portion A512 protrudes in a columnar shape (for example, cylindrical shape) from the main surface A511a of the bottom portion A511. The spring support portion A512 can be fitted into the inner diameter portion of the lower end of the contact pressure spring A53.

[0148] The two side wall portions A513 are connected to the two side wall portions A522 of the upper holder portion A52, which will be described later. The two side wall portions A513 are, for example, flat plates and protrude upward from both ends in the front-rear direction Y3 of the bottom portion A511. The two side wall portions A513 are spaced apart from each other in the front-rear direction Y3.

[0149] The connecting portion A514 connects to the upper end of the movable shaft 24. The connecting portion A514 is, for example, cylindrical, and the upper end of the movable shaft 24 is inserted into and fixed to it.

[0150] The upper holder portion A52 is positioned above the movable contact 22 and is connected to the lower holder portion A51 with a housing space between them. The movable contact 22 and the contact pressure spring 53 are held in this housing space between the upper holder portion A52 and the lower holder portion A51. The upper holder portion A52 is made of, for example, metal.

[0151] The upper holder portion A52 has a covering portion A521, a convex region A523, and two side wall portions A522.

[0152] The covering portion A521 is a covering portion that covers the upper side of the movable contact 22, and is, for example, a rectangular flat plate. The covering portion A521 covers the central part in the left-right direction Y1 on the opposing surface A22a of the movable contact 22. The covering portion A521 has an opposing surface A521a that faces the movable contact 22.

[0153] As shown in Figure 11, the convex region A523 is provided on the opposing surface A521a of the covering portion A521. The convex region A523 has the same function as the convex region A51d of Embodiment 1 and is formed in the same way as the convex region A51d of Embodiment 1. More specifically, the convex region A51d is the portion that contacts the opposing surface A22a of the movable contact 22 when the upper yoke 51 is struck against the opposing surface A22a of the movable contact 22. The plan view shape of the convex region A523 is a rectangle when viewed from the vertical direction Y2. The plan view rectangle shape of the convex region A523 is a rectangle in which the length in the front-to-back direction Y3 is longer than the length in the left-to-right direction Y1.

[0154] The two side wall portions A522 are connected to the two side wall portions A513 of the lower holder portion A51. The two side wall portions A522 are, for example, flat plates and protrude downward from both ends in the front-rear direction Y3 of the covering portion A521. The two side wall portions A522 are spaced apart in the front-rear direction Y3 and face each other. The two side wall portions A522 correspond one-to-one with the two side wall portions A513 of the lower holder portion A51 and are connected to the corresponding side walls.

[0155] The lower holder portion A51 and the upper holder portion A52 are connected to each other by the connection of their respective two side wall portions A513 and two side wall portions A522. A housing space is formed between the lower holder portion A51 and the upper holder portion A52, extending in the left-right direction. The movable contact element 22 and the contact pressure spring A53 are housed in this housing space.

[0156] The movable contact 22 of Embodiment 3 (hereinafter simply referred to as the movable contact 22) is formed similarly to the movable contact 22 of Embodiment 1, except that a positioning portion A22c for positioning the upper end of the contact pressure spring A53 is provided on the lower main surface A22b of the movable contact 22 (the main surface opposite to the opposing surface A22a) (see Figure 11).

[0157] The movable contact 22 is housed in a housing space between the lower holder portion A51 and the upper holder portion A52 so as to be able to move up and down. The movable contact 22 protrudes from the housing space in the left and right directions.

[0158] The contact pressure spring A53 of Embodiment 3 (hereinafter simply referred to as contact pressure spring A53) is configured in the same way as the contact pressure spring 55 of Embodiment 1.

[0159] The contact pressure spring A53 is positioned between the movable contact 22 and the lower yoke 52 (more specifically, between the positioning portion A22c of the movable contact 22 and the spring receiving portion A512 of the lower holder portion A51) in a compressed state in the vertical direction Y2. The contact pressure spring A53 biases the movable contact 22 toward the covering portion A521.

[0160] In Embodiment 3, as with Embodiment 1, when the covering portion A521 of the upper holder portion A52 strikes the opposing surface A22a of the movable contact 22, the convex region A523 generates a force moment around an axis extending in the left-right direction Y1, and this force moment effectively separates the movable contact 22 from the pair of fixed contacts 211.

[0161] (2) The contact device 2 according to Embodiment 3 also produces the same effects as in Embodiment 1.

[0162] (3) Modifications Below, modifications of Embodiment 3 will be described.

[0163] In Embodiment 3, the convex region A523 is provided on the second opposing surface 521a of the covering portion A521 of the holder A50. However, instead of being provided on the second opposing surface 521a of the covering portion A521, the convex region A523 may be provided on the opposing surface A22a of the movable contact 22. In this case as well, the same effects as in Embodiment 3 are achieved. That is, from Embodiment 3 and this modification, the convex region A51d only needs to be provided on one of the opposing surfaces A22a of the movable contact 22 and A521a of the covering portion A521.

[0164] (Aspects) The following aspects are disclosed in this specification.

[0165] The contact device (2) of the first embodiment comprises a pair of fixed contacts (211), a movable contact (22), a holder (23, A50), and a movable shaft (24). The pair of fixed contacts (211) are arranged in the left-right direction (Y1). The movable contact (22) moves toward and toward the pair of fixed contacts (211) in the up-down direction (Y2), which is perpendicular to the left-right direction (Y1). The holder (23, A50) holds the movable contact (22). The movable shaft (24) moves the holder (23) in the up-down direction (Y2) so that the movable contact (22) moves toward and toward the pair of fixed contacts (211). The holder (23, A50) includes a covering portion (upper yoke 51, covering portion A521). The covering portion (yoke 51 or covering portion A521) is positioned on the side of the pair of fixed contacts (211) on the movable contact (22) and covers a part of the movable contact (22). The opposing surface (A22a) of the movable contact (22) and the opposing surfaces (A51a, A521a) of the covering portion (yoke 51, covering portion A521) face each other. A convex region (A51d, A523) is provided on the first opposing surface, which is one of the opposing surfaces (A51a, A521a) of the movable contact (22) and the covering portion (yoke 51 or covering portion A521). The convex regions (A51d, A523) contact and separate from the second opposing surface, which is the other of the opposing surfaces (A51a, A521a) of the movable contactor (22) and the covering portion (yoke 51, covering portion A521). The convex regions (A51d, A523) have a rectangular shape when viewed from above (Y2).

[0166] With this configuration, since the convex regions (A51d, A523) provided on the first opposing surface are rectangular in shape, the contact area between the convex regions (A51d, A523) and the second opposing surface can be increased compared to the case where the convex regions (A51d, A523) are circular. Therefore, the gradual indentation of the second opposing surface over time due to the convex regions (A51d, A523) pressing against it can be reduced. As a result, the peeling performance when peeling the movable contact (22) from the pair of fixed contacts (211) can be improved.

[0167] Furthermore, because the convex regions (A51d, A523) are rectangular in shape, when the convex region (A51d) strikes the second opposing surface, a moment of force (AM1) can be effectively generated around an axis extending in the front-to-back direction (Y3) that is perpendicular to the left-to-right direction (Y1) and the up-to-down direction (Y2) on the movable contact (22). This allows the movable contact (22) to be effectively separated from the pair of fixed contacts (211). In other words, the separation performance when separating the movable contact (22) from the pair of fixed contacts (211) can be further improved.

[0168] In the second embodiment of the contact device (2), in the first embodiment, the holder (23) includes an upper yoke (51), a lower yoke (52), a contact pressure spring (55), and a holder body (56). The lower yoke (52) is fixed to the main surface (A22b), which is the opposite surface (A22a) of the movable contact (22). The contact pressure spring (55) biases the lower yoke (52) toward the upper yoke (51). The holder body (56) is fixed to the upper yoke (51) and holds the movable contact (22) and the lower yoke (52) so that they can be displaced relative to each other in the vertical direction (Y2).

[0169] With this configuration, even when the covering portion is the upper yoke (51), the peeling performance when peeling the movable contact (22) from the pair of fixed contacts (211) can be improved.

[0170] In the third embodiment of the contact device (2), in the second embodiment, the height of the convex region (A51d) from the first opposing surface is such that when the convex region (A51d) contacts the second opposing surface while the opposing surface (A51a) of the upper yoke (51) is inclined with respect to the opposing surface (A22a) of the movable contactor (22), the portion of the first opposing surface other than the convex region (A51d) does not come into contact with the second opposing surface.

[0171] With this configuration, when the convex region (A51d) contacts the second opposing surface while the opposing surface (A51a) of the upper yoke (51) is inclined with respect to the opposing surface (A22a) of the movable contact (22), a force moment (AM1) around an axis extending in the vertical direction (Y2) can be effectively generated.

[0172] In the fourth embodiment of the contact device (2), in any one of the first to third embodiments, the length in the left-right direction (Y1) of the convex region (A51d) is smaller than the length in the left-right direction (Y1) of the first opposing surface.

[0173] This configuration reduces the generation of force moments around an axis extending in the front-to-back direction (Y3) that is perpendicular to the left-to-right direction (Y1) and the up-to-down direction (Y2). Therefore, the imbalance between the force pulling the movable contact (22) away from one of the pair of fixed contacts (211) and the force pulling the movable contact (22) away from the other of the pair of fixed contacts (211) can be reduced. As a result, the movable contact (22) can be effectively pulled away from the pair of fixed contacts (211).

[0174] In the fifth embodiment of the contact device (2), in any one of the first to fourth embodiments, the rectangular shape of the convex region (A51d) is a rectangle in which the length in the front-to-back direction (Y3), which is perpendicular to the left-to-right direction (Y1) and the up-to-down direction (Y2), is longer than the length in the left-to-right direction (Y1).

[0175] This configuration allows for an even greater distance between the fulcrum (AP1) and the point of application of force (AP2) in the above-mentioned moment of force (AM1). Therefore, the above-mentioned moment of force (AM1) can be made even larger. As a result, the peeling performance when separating the movable contact (22) from the pair of fixed contacts (211) can be further improved.

[0176] In the sixth embodiment of the contact device (2), in any one of the first to fifth embodiments, the convex regions (A51d, A523) are provided on the opposing surfaces (A51a, A521a) of the covering portion (yoke 51, covering portion A521). The length of the convex regions (A51d, A523) in the front-to-back direction (Y3), which is perpendicular to the left-to-right direction (Y1) and the up-to-down direction (Y2), is the same as the length of the front-to-back direction (Y3) of the opposing surface (A22a) of the movable contact (22).

[0177] This configuration allows for an even greater distance between the fulcrum (AP1) and the point of application of force (AP2) in the above-mentioned moment of force (AM1). Therefore, the above-mentioned moment of force (AM1) can be made even larger. As a result, the peeling performance when separating the movable contact (22) from the pair of fixed contacts (211) can be further improved.

[0178] In the seventh embodiment of the contact device (2), in any one of the first to sixth embodiments, in the front-to-back direction (Y3) perpendicular to the left-to-right direction (Y1) and the up-to-down direction (Y2), the opposing surfaces (A51a, A521a) of the covering portion (upper yoke 51, covering portion A521) are inclined with respect to the opposing surface (A22a) of the movable contact (22), and the convex region (A51d) is in contact with the second opposing surface.

[0179] With this configuration, when the convex regions (A51d, A523) strike the second opposing surface, a moment of force (AM1) can be generated in the movable contact (22) around an axis extending in the front-rear direction (Y3). This improves the peeling performance when peeling the movable contact (22) from the pair of fixed contacts (211).

[0180] The eighth aspect of the contact device (2) comprises a pair of fixed contacts (211), a movable contact (22), a holder (23), and a movable shaft (24). The pair of fixed contacts (211) are arranged in the left-right direction (Y1). The movable contact (22) moves toward and toward the pair of fixed contacts (211) in the up-down direction (Y2), which is perpendicular to the left-right direction (Y1). The holder (23) holds the movable contact (22). The movable shaft (24) moves the holder (23) in the up-down direction (Y2) so that the movable contact (22) moves toward and toward the pair of fixed contacts (211). The holder (23) includes an upper yoke (51), a lower yoke (52), a contact pressure spring (55), and a holder body (56). The upper yoke (51) is positioned above the movable contact (22). The lower yoke (52) is fixed to the lower surface of the movable contact (22). A contact pressure spring (55) biases the lower yoke (52) toward the upper yoke (51). The holder body (56) is fixed to the upper yoke (51) and holds the movable contact (22) and the lower yoke (52) so that they can be displaced relative to each other in the vertical direction (Y2). The lower yoke (52) has a pair of first magnetic pole regions (A522a). The pair of first magnetic pole regions (A522a) are arranged on both sides of the movable contact (22) in the front-rear direction (Y3) which is perpendicular to the left-right direction (Y1) and the up-down direction (Y2). The opposing surface (A51a) of the upper yoke (51) that faces the movable contact (22) has a pair of second magnetic pole regions (A51c). A pair of second pole regions (A51c) face a pair of first pole regions (A522a). A pair of convex regions (A522b, A522c) are provided in one of the pair of first pole regions (A522a) and the pair of second pole regions (A51c). The pair of convex regions (A522b, A522c) are in contact with and separated from the other pair of pole regions (A522a) and the pair of second pole regions (A51c).

[0181] In this configuration, the pair of convex regions (A522b, A522c) are provided on one of the pair of first magnetic pole regions (A522a) of the lower yoke (52) and the pair of second magnetic pole regions (A51c) of the upper yoke (51). The lower yoke (52) and upper yoke (51) are usually formed of a magnetic material (i.e., a material that is relatively harder than the material of the movable contact (22) (e.g., copper)). Therefore, even if the pair of convex regions (A522b, A522c) press against the other pair of magnetic pole regions, the gradual recession of the other pair of magnetic pole regions over time can be reduced. As a result, the peeling performance when peeling the movable contact (22) from the pair of fixed contacts (211) can be improved.

[0182] Furthermore, the pair of convex regions (A522b, A522c) are provided in one of the pair of first pole regions (A522a) of the lower yoke (52) and the pair of second pole regions (A51c) of the upper yoke (51). Therefore, when the pair of convex regions (A522b, A522c) strike the other pair of pole regions, a force moment (AM2) around the axis extending in the front-rear direction (Y3) can be effectively generated on the movable contact (22). This allows the movable contact (22) to be effectively separated from the pair of fixed contacts (211). In other words, the separation performance when separating the movable contact (22) from the pair of fixed contacts (211) can be further improved.

[0183] In the ninth aspect of the contact device (2), in the eighth aspect, the height of one pair of pole regions in a pair of convex regions (A522b, A522c) is such that when the opposing surface (A51a) of the upper yoke (51) is inclined with respect to the pair of first pole regions (A522a) of the lower yoke (52), and one of the pair of convex regions (A522b, A522c) comes into contact with one of the other pair of pole regions, the portion of one pair of pole regions other than the pair of convex regions (A522b, A522c) does not come into contact with the other pair of pole regions.

[0184] With this configuration, when the opposing surface (A51a) of the upper yoke (51) 51 is inclined with respect to the pair of first magnetic pole regions (A522a) of the lower yoke (52), and the pair of convex regions (A522b, A522c) come into contact with the other pair of magnetic pole regions, a force moment (AM2) around an axis extending in the vertical direction (Y2) can be effectively generated.

[0185] In the tenth embodiment of the contact device (2), in the eighth or ninth embodiment, the length in the left-right direction (Y1) of a pair of convex regions (A522b, A522c) is smaller than the length in the left-right direction (Y1) of one of the pair of magnetic pole regions.

[0186] This configuration reduces the generation of a force moment (AM2) around an axis extending in the front-to-back direction (Y3) that is perpendicular to the left-to-right direction (Y1) and the up-to-down direction (Y2). Therefore, the imbalance between the force pulling the movable contact (22) away from one of the pair of fixed contacts (211) and the force pulling the movable contact (22) away from the other of the pair of fixed contacts (211) can be reduced. As a result, the movable contact (22) can be effectively pulled away from the pair of fixed contacts (211).

[0187] In the 11th embodiment of the contact device (2), in any one of the 8th to 10th embodiments, in the front-to-back direction (Y3) perpendicular to the left-to-right direction (Y1) and the up-to-down direction (Y2), the opposing surface (A51a) of the upper yoke (51) is inclined relative to a pair of first magnetic pole regions (A522a), and one of the pair of convex regions (A522b, A522c) is in contact with one of the other pair of magnetic pole regions.

[0188] With this configuration, when the convex regions (A522b, A522c) strike the other pair of magnetic pole regions, a force moment (AM2) can be generated in the movable contact (22) around an axis extending in the front-rear direction (Y3). This improves the peeling performance when separating the movable contact (22) from the pair of fixed contacts (211).

[0189] The electromagnetic relay (1) of the twelfth embodiment comprises a contact device (2) of any one of the first to eleventh embodiments and an electromagnet device (3). The electromagnet device (3) drives a movable shaft (24) so ​​that a movable contact (22) moves toward and away from a pair of fixed contacts (211).

[0190] This configuration provides an electromagnetic relay (1) that achieves the above-mentioned effects of the contact device (2).

[0191] 1 Electromagnetic relay 2 Contact device 3 Electromagnet device 22 Movable contact 23 Holder 24 Movable shaft 51 Upper yoke (covering part) 52 Lower yoke 55 Contact pressure spring 56 Holder body 211 Fixed contact A22a Opposing surface A22b Main surface A50 Holder A51 Lower holder part A51a Opposing surface A51c Second magnetic pole region A51d Convex region A511 Bottom A511a, A511b Main surface A52 Upper holder part A521 Covering part A521a Opposing surface A522a First magnetic pole region A522b, A522c Convex region A523 Convex region AM1, AM2 Moment AP1 Pivot AP2 Point of force Y1 Left and right direction Y2 Up and down direction Y3 Back and forth direction

Claims

1. A contact device comprising: a pair of fixed contacts arranged in the left-right direction; a movable contact that moves toward and toward the pair of fixed contacts in the up-down direction perpendicular to the left-right direction; a holder that holds the movable contact; and a movable shaft that moves the holder in the up-down direction so that the movable contact moves toward and toward the pair of fixed contacts, wherein the holder includes a covering portion that is positioned on the side of the pair of fixed contacts of the movable contact and covers a part of the movable contact; the opposing surfaces of the movable contact and the opposing surfaces of the covering portion are opposite to each other; a convex region is provided on one of the opposing surfaces of the movable contact and the opposing surfaces of the covering portion; the convex region contacts and separates from a second opposing surface which is the other of the opposing surfaces of the movable contact and the opposing surfaces of the covering portion; and the convex region has a rectangular shape when viewed from above in the up-down direction.

2. The contact device according to claim 1, wherein the holder comprises: an upper yoke constituting the covering portion; a lower yoke fixed to the main surface of the movable contact which is the opposite surface of the movable contact; a contact pressure spring that biases the lower yoke toward the upper yoke; and a holder body fixed to the upper yoke, which holds the movable contact and the lower yoke so that they can be displaced relative to each other in the vertical direction.

3. The contact device according to claim 2, wherein the height of the convex region from the first opposing surface is such that, when the convex region contacts the second opposing surface while the opposing surface of the upper yoke is inclined with respect to the opposing surface of the movable contactor, the portion of the first opposing surface other than the convex region does not come into contact with the second opposing surface.

4. The length in the left-right direction of the convex region is smaller than the length in the left-right direction of the first opposing surface, the contact device according to any one of claims 1 to 3.

5. The contact device according to any one of claims 1 to 4, wherein the rectangular shape of the convex region is a rectangle in which the length in the front-to-back direction, which is perpendicular to the left-to-right direction and the up-to-down direction, is longer than the length in the left-to-right direction.

6. The contact device according to any one of claims 1 to 5, wherein the convex region is provided on the opposing surface of the covering portion, and the length of the convex region in the front-rear direction perpendicular to the left-right direction and the up-down direction is the same length as the length of the opposing surface of the movable contact in the front-rear direction.

7. The contact device according to any one of claims 1 to 6, wherein, in the front-rear direction perpendicular to the left-right and up-down directions, the opposing surface of the covering portion is inclined with respect to the opposing surface of the movable contact, and the convex region is in contact with the second opposing surface.

8. A device comprising: a pair of fixed contacts arranged in the left-right direction; a movable contact that moves toward and toward the pair of fixed contacts in the up-down direction perpendicular to the left-right direction; a holder that holds the movable contact; and a movable shaft that moves the holder in the up-down direction so that the movable contact moves toward and toward the pair of fixed contacts, wherein the holder includes: an upper yoke positioned above the movable contact; a lower yoke fixed to the lower surface of the movable contact; a contact pressure spring that biases the lower yoke toward the upper yoke; and a holder body fixed to the upper yoke that holds the movable contact and the lower yoke so that they can be displaced relative to each other in the up-down direction, wherein the lower yoke has a pair of first magnetic pole regions positioned on both sides of the movable contact in the front-rear direction perpendicular to the left-right direction and the up-down direction; the opposing surface of the upper yoke facing the movable contact has a pair of second magnetic pole regions facing the pair of first magnetic pole regions; and a pair of convex regions are provided in one of the pair of first magnetic pole regions and the pair of second magnetic pole regions. A contact device wherein the pair of convex regions contact and separate from the other pair of magnetic pole regions among the pair of first magnetic pole regions and the pair of second magnetic pole regions.

9. The contact device according to claim 8, wherein the height of the pair of convex regions from one of the pair of magnetic pole regions is such that, when the opposing surface of the upper yoke is inclined with respect to the pair of first magnetic pole regions of the lower yoke, one of the pair of convex regions contacts one of the other pair of magnetic pole regions, and the portion of the one pair of magnetic pole regions other than the pair of convex regions does not come into contact with the other pair of magnetic pole regions.

10. The contact device according to claim 8 or 9, wherein the length in the left-right direction of the pair of convex regions is smaller than the length in the left-right direction of one of the pair of magnetic pole regions.

11. The contact device according to any one of claims 8 to 10, wherein the opposing surfaces of the upper yoke are inclined relative to the pair of first magnetic pole regions in the front-rear direction perpendicular to the left-right and up-down directions, and the pair of convex regions are in contact with the other pair of magnetic pole regions.

12. An electromagnetic relay comprising: a contact device according to any one of claims 1 to 11; and an electromagnet device that drives the movable shaft so that the movable contact moves toward and away from the pair of fixed contacts.

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