Electromagnetic relay

Abstract

In an electromagnetic relay (1), a plunger (2) advances and retreats a movable element (3) such that a fixed contact (41) and a movable contact (31) are brought into contact with each other and separated from each other. The solenoid section (5) advances and retreats the plunger (2). The solenoid section (5) has an electromagnetic coil (53), a fixed core section (51), and a movable core section (52). The fixed core section (51) has a plate section (511). The plate section (511) is disposed further toward the front side (Z1) than the electromagnetic coil (53), and is formed so as to overlap the electromagnetic coil (53) when viewed from the forward / backward direction (Z) of the plunger (2). The plate part (511) and the fixed inner side part (512) of the fixed core part (51) are integrally formed. In the fixed core part (51), a fixed curved surface (513) is formed between the outer peripheral surface of the fixed inner side part (512) and the rear side surface of the plate part (511), and the fixed curved surface (513) is curved in a state of protruding toward the plunger (2) side.

Description

Citation of Related Applications

[0001] This application is based on Japanese Patent Application No. 2022-194255 filed on December 5, 2022, and the contents thereof are incorporated herein by reference. Technical Field

[0002] The present disclosure relates to an electromagnetic relay. Background Art

[0003] For example, as disclosed in Patent Document 1, an electromagnetic relay is known in which a movable member is moved by a magnetic attractive force generated by energizing an electromagnetic coil to bring a fixed contact into contact with and separate from a movable contact of the movable member. In the electromagnetic relay described in Patent Document 1, a yoke portion provided at a position closer to the front side than the electromagnetic coil and a fixed core portion disposed inside the electromagnetic coil are separate bodies and are riveted and fixed to the fixed core portion.

[0004] Further, in the electromagnetic relay described in Patent Document 1, a gap is formed between a magnetic member composed of the fixed core portion and the above-described yoke portion and the electromagnetic coil. Thereby, other members can be disposed between the magnetic member and the electromagnetic coil, and assembly can be easily performed. Prior Art Documents Patent Documents

[0005] Patent Document 1: Japanese Patent Laid-Open No. 2010-10058 Summary of the Invention

[0006] In the electromagnetic relay described in Patent Document 1, at the connecting portion between the above-described yoke portion and the fixed core portion, the rear surface of the yoke portion intersects the outer peripheral surface of the fixed core portion at a right angle. Therefore, the distance between the connecting portion between the above-described yoke portion and the fixed core portion and the winding portion formed by winding the wire in the electromagnetic coil is likely to be long. Therefore, from the viewpoint of magnetic efficiency, there is room for improvement.

[0007] The present disclosure aims to provide an electromagnetic relay capable of improving magnetic efficiency.

[0008] An electromagnetic relay according to one aspect of the present disclosure includes: a movable member having a movable contact that contacts and separates from a fixed contact; a plunger that moves the movable member forward and backward to bring the fixed contact into contact with and separate from the movable contact; and a solenoid unit that moves the plunger forward and backward, wherein the solenoid unit includes: an electromagnetic coil including a winding portion formed by winding a wire, and forming a magnetic flux by energizing the winding portion; A fixed core including an insertion through-hole for inserting the plunger, and a part of which is disposed inside the electromagnetic coil; and A movable core disposed at a position rearward of the fixed core and fixed to the plunger, The fixed core and the movable core constitute a magnetic path of the magnetic flux formed by energizing the winding portion, The movable core moves forward and backward relative to the fixed core as the winding portion is energized, The fixed core has a plate portion disposed at a position forward of the electromagnetic coil and formed to overlap the electromagnetic coil when viewed in the advancing and retreating direction of the plunger, This plate portion is integrally formed with the fixed inner portion of the fixed core disposed inside the electromagnetic coil, A gap is formed between the electromagnetic coil and the fixed core, In the fixed core, a fixed curved surface that is curved in a state of protruding toward the plunger side is formed between the outer peripheral surface of the fixed inner portion and the rear surface of the plate portion.

[0009] In the electromagnetic relay, the fixed inner portion and the plate portion are integrally formed, and a fixed curved surface is formed between the outer peripheral surface of the fixed inner portion of the fixed core and the rear surface of the plate portion. Therefore, the connecting portion between the fixed inner portion and the plate portion is likely to approach the winding portion of the electromagnetic coil. As a result, the magnetic efficiency can be improved.

[0010] As described above, according to the above manner, an electromagnetic relay capable of improving the magnetic efficiency can be provided. In addition, the symbols in parentheses described in the claims indicate the correspondence with the specific elements described in the following embodiments, and do not limit the technical scope of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The above objects, other objects, features, and advantages of the present disclosure can be made more apparent by referring to the drawings and the following detailed description. The drawings are as follows. Figure 1 It is a cross-sectional view showing a state where the fixed contact and the movable contact of the electromagnetic relay including the winding shaft in the first embodiment are separated. Figure 2 It is a cross-sectional view showing a state where the fixed contact and the movable contact of the electromagnetic relay including the winding shaft in the first embodiment are in contact with each other. Figure 3 It is an enlarged cross-sectional view of the vicinity of the fixed curved surface in the first embodiment. Figure 4 It is a cross-sectional view showing the magnetic flux passing through the magnetic path in the first embodiment. Figure 5It is a cross-sectional view showing the case where the metal member is inserted through the recess in the first embodiment. Figure 6 It is a cross-sectional view showing the case where the metal member is plastically deformed using a stamping jig in the first embodiment. Figure 7 It is a cross-sectional view of the metal member formed with a plate-like portion in the first embodiment. Figure 8 It is a view of the metal member formed with a plate-like portion in the first embodiment as observed from the axial direction of the metal member. Figure 9 It is a view of the metal member after blanking the plate-like portion in the first embodiment. Figure 10 It is a cross-sectional view comparing the state where the fixed contact and the movable contact of the electromagnetic relay including the winding shaft are separated in the first comparative method. Figure 11 It is an enlarged cross-sectional view of the vicinity of the connecting portion between the fixed core portion and the plate portion in the first comparative method. Figure 12 It is an enlarged cross-sectional view of the vicinity of the fixed surface in the second embodiment. Figure 13 It is an enlarged cross-sectional view of the vicinity of the fixed surface in the third embodiment. Figure 14 It is an enlarged cross-sectional view of the vicinity of the fixed surface in the fourth embodiment. Detailed implementation mode

[0012] (First embodiment) Refer to Figures 1 to 9 to describe the embodiment of the electromagnetic relay. As Figure 1 , Figure 2 shown, the electromagnetic relay 1 of this mode has a movable member 3, a plunger 2, and a solenoid portion 5. The movable member 3 has a movable contact 31 that contacts and separates from the fixed contact 41. The plunger 2 moves the movable member 3 forward and backward to make the fixed contact 41 contact and separate from the movable contact 31. The solenoid portion 5 moves the plunger 2 forward and backward.

[0013] The solenoid portion 5 has an electromagnetic coil 53, a fixed core portion 51, and a movable core portion 52. The electromagnetic coil 53 has a winding portion 531 formed by winding a wire, and as Figure 4As shown, a magnetic flux φ is formed by energizing the winding portion 531. The fixed core portion 51 includes an insertion through-hole 514 through which the plunger 2 is inserted, and a part of it is disposed inside the electromagnetic coil 53. The movable core portion 52 is disposed at a position rearward of the fixed core portion 51 in the Z2 direction and is fixed to the plunger 2. The fixed core portion 51 and the movable core portion 52 constitute a magnetic path for the magnetic flux φ formed by energizing the winding portion 531. The movable core portion 52 moves forward and backward relative to the fixed core portion 51 as the winding portion 531 is energized.

[0014] The fixed core portion 51 has a plate portion 511. The plate portion 511 is disposed at a position forward of the electromagnetic coil 53 in the Z1 direction and is formed to overlap the electromagnetic coil 53 when viewed from the advancing and retreating direction Z of the plunger 2 (illustrations are omitted). The plate portion 511 and the fixed inner portion 512 of the fixed core portion 51 disposed inside the electromagnetic coil 53 are integrally formed.

[0015] In addition, a gap 11 is formed between the electromagnetic coil 53 and the fixed core portion 51. In the fixed core portion 51, a fixed curved surface 513 that is bent in a state of protruding toward the plunger 2 side is formed between the outer peripheral surface of the fixed inner portion 512 and the rear surface of the plate portion 511.

[0016] In this specification, the side where the movable core portion 52 approaches the fixed core portion 51 in the advancing and retreating direction Z of the plunger 2 is referred to as the front side Z1, and the opposite side is referred to as the rear side Z2. In addition, the radial direction refers to the radial direction of a circle centered on the winding axis C of the winding portion 531 when the electromagnetic relay 1 is viewed from the advancing and retreating direction Z (illustrations are omitted). In addition, the circumferential direction refers to the direction along the circumference of a circle centered on the winding axis C when the electromagnetic relay 1 is viewed from the advancing and retreating direction Z. In addition, in this embodiment, the winding portion 531 is formed such that the winding axis C extends along the advancing and retreating direction Z.

[0017] The electromagnetic relay 1 can be used, for example, as a system main relay or a main relay for rapid charging in an electric vehicle, a hybrid vehicle, etc. In addition, when the electromagnetic relay 1 is used as a system main relay or a main relay for rapid charging, the electromagnetic relay 1 can be used, for example, as a high-capacity relay of 400 A or less or a relay compatible with 800 V.

[0018] As Figure 1 shown, the electromagnetic relay 1 of this embodiment has a housing 12 that houses the movable member 3, the plunger 2, and the solenoid portion 5. The housing 12 is made of an insulating material such as resin, for example.

[0019] In addition, the electromagnetic relay 1 of this embodiment has a cylindrical sealing housing 71 inside the housing 12. The rear end of the sealing housing 71 is fixed to the outer peripheral end of the plate portion 511. Inside the space surrounded by the sealing housing 71 and the plate portion 511, a movable contact 31 and a fixed contact 41 are disposed. This space is appropriately referred to as the contact arrangement space 701.

[0020] The rear end of the sealed housing 71 is fixed to the plate portion 511 in a sealed state with the plate portion 511 over the entire circumference. The sealed housing 71 is made of, for example, ceramics. In this embodiment, a sandwiching member 72 made of iron or the like is disposed between the sealed housing 71 and the plate portion 511. The sandwiching member 72 and the plate portion 511 are welded, and the sandwiching member 72 and the sealed housing 71 are brazed, thereby fixing the sealed housing 71 and the plate portion 511 and ensuring the seal between the two.

[0021] Two fixed terminals 40 that are electrically insulated from each other are fixed to the sealed housing 71. The fixed terminals 40 are inserted into through holes 711 formed in the sealed housing 71, and a part of the fixed terminals 40 is disposed inside the cylindrical sealed housing 71. The fixed terminals 40 are hermetically sealed to the sealed housing 71 by brazing. In addition, the fixed terminals 40 are also inserted into through holes formed in the housing 12. Fixed contacts 41 are provided at the rear ends of the respective fixed terminals 40. The two fixed contacts 41 face the rear side Z2 in the advancing and retreating direction Z. The fixed terminals 40 are made of a conductive material such as copper, for example.

[0022] Two movable contacts 31 are arranged so as to face the two fixed contacts 41 from the rear side Z2 in the advancing and retreating direction Z, respectively. The two movable contacts 31 are provided on the front side Z1 of a movable member 3. The movable member 3 is made of, for example, a metal plate. The shaft 21 of the plunger 2 passes through the portion of the movable member 3 between the two movable contacts 31. The movable member 3 is held by the shaft 21 via a holding member 22 that holds the movable member 3. The holding member 22 has: a base portion 27 made of resin; a cylindrical shaft support portion 26 arranged to surround a part of the shaft 21 from the outer peripheral side; and a movable yoke portion 25 disposed around the movable member 3. In this embodiment, the base portion 27, the movable member 3, the shaft support portion 26, and the movable yoke portion 25 are integrally formed by insert molding. In addition, the shaft 21 and the holding member 22 are arranged so as to be slidable relative to each other in the advancing and retreating direction Z. A contact compression spring 23 that elastically supports the holding member 22 in the advancing and retreating direction Z is provided on the outer peripheral side of the shaft 21 and on the rear side Z2 of the holding member 22. The rear end of the contact compression spring 23 abuts against a support member 24 fixed to the shaft 21. The front end of the contact compression spring 23 abuts against the rear surface of the movable yoke portion 25.

[0023] The shaft 21 is slidably inserted into an insertion hole 514 formed in the fixed core portion 51. In this embodiment, the shaft 21 is made of a non-magnetic metal and is a rod-shaped member whose longitudinal direction is the advancing and retreating direction Z. In addition, in this embodiment, the winding shaft C of the winding portion 531 is also the central axis of the shaft 21.

[0024] In addition, as Figure 4As shown, an electromagnetic coil 53 is disposed at a position closer to the rear side Z2 than the plate portion 511. The electromagnetic coil 53 has an insulating bobbin 532. The winding portion 531 is formed by winding a wire around the outer periphery of the cylindrical portion 533 of the bobbin 532. The cylindrical portion 533 is open in both directions of the advancing and retreating direction Z.

[0025] The bobbin 532 does not contact the fixed curved surface 513 of the fixed core portion 51. That is, the electromagnetic coil 53 does not contact the fixed curved surface 513. A gap 11 is formed between the electromagnetic coil 53 and the fixed curved surface 513. In addition, a gap 11 is also formed between the fixed inner portion 512 in the radial direction and the electromagnetic coil 53 and between the plate portion 511 in the advancing and retreating direction Z and the electromagnetic coil 53.

[0026] In addition, the fixed inner portion 512 of the fixed core portion 51 and the movable core portion 52 are disposed inside the cylindrical portion 533. In addition, a return spring 13 is disposed between the fixed core portion 51 and the movable core portion 52 in the advancing and retreating direction Z. The return spring 13 is composed of a helical spring and is disposed between the fixed core portion 51 and the movable core portion 52 in an elastically compressed state. That is, the return spring 13 applies a force to the movable core portion 52 in a direction to separate the movable contact 31 from the fixed contact 41.

[0027] In addition, a sleeve 73 that hermetically seals the return spring 13 and the movable core portion 52 is directly or indirectly fixed to the fixed core portion 51. In the present embodiment, the sleeve 73 is directly joined to the outer peripheral surface of the fixed inner portion 512. The outer peripheral surface of the fixed inner portion 512 is a surface parallel to the advancing and retreating direction Z. In addition, the material of the sleeve 73 is not particularly limited and can be, for example, stainless steel.

[0028] The sleeve 73 covers the rear end surface and the outer peripheral surface of the movable core portion 52. The sleeve 73 has a bottomed cylindrical shape. The front end portion of the sleeve 73 is disposed in the gap 11 between the electromagnetic coil 53 and the fixed inner portion 512. The front end portion of the sleeve 73 does not contact the plate portion 511 and is fixed to the fixed inner portion 512 at a position closer to the rear side Z2 than the fixed curved surface 513. The front end portion of the sleeve 73 faces the fixed curved surface 513 in the advancing and retreating direction Z.

[0029] The inner peripheral surface of the sleeve 73 and the outer peripheral surface of the fixed inner portion 512 are sealed around the entire circumference. The sleeve 73 and the outer peripheral surface of the fixed inner portion 512 are welded, for example, around the entire circumference.

[0030] Accordingly, in the space surrounded by the sleeve 73 and the fixed core 51 (hereinafter, appropriately referred to as the core arrangement space 702), the movable core 52 and the return spring 13 are hermetically sealed. However, there is a minute gap between the insertion through-hole 514 of the fixed core 51 and the outer peripheral surface of the shaft 21. Therefore, the core arrangement space 702 and the contact arrangement space 701 communicate with each other through this gap. However, both the core arrangement space 702 and the contact arrangement space 701 are hermetically sealed from other exteriors. Accordingly, the contact arrangement space 701 is hermetically sealed from the exterior. Moreover, a gas such as hydrogen or nitrogen is sealed in the contact arrangement space 701.

[0031] In addition, in this embodiment, the solenoid unit 5 has two yokes 61 and 62 disposed around the electromagnetic coil 53. By energizing the winding portion 531 of the electromagnetic coil 53, a magnetic flux φ flows in the magnetic circuit formed by the fixed core 51, the movable core 52, and the yokes 61 and 62, and the fixed core 51 and the movable core 52 are magnetized. Thereby, a magnetic attractive force is generated between the movable core 52 and the fixed core 51.

[0032] The yoke 61 is formed in a cylindrical shape and is disposed between the portion on the rear side Z2 of the electromagnetic coil 53 in the radial direction and the movable core 52. The yoke 62 has a rear side portion 621 that covers the rear side of the electromagnetic coil 53 and an outer peripheral portion 622 that covers the outer periphery of the electromagnetic coil 53 from the radial outside. The outer peripheral portion 622 extends from the outer peripheral end of the rear side portion 621 toward the front side Z1. The outer peripheral portion 622 is formed in a cylindrical shape.

[0033] In addition, the outer peripheral surface of the fixed inner portion 512 of the fixed core 51 is formed along the inner peripheral surface of the cylindrical portion 533 of the bobbin 532. The fixed inner portion 512 is disposed opposite to the movable core 52 in the forward and backward direction Z. The fixed core 51 and the movable core 52 are each made of a soft magnetic metal.

[0034] The plate portion 511 of the fixed core 51 is formed in a flat plate shape that expands radially outward from the front end portion of the fixed inner portion 512. The plate portion 511 covers the front of the electromagnetic coil 53. The plate portion 511 is provided so as to overlap the entire electromagnetic coil 53 when viewed from the forward and backward direction Z (illustration omitted). In addition, the plate portion 511 is formed at a position on the fixed core 51 that is closer to the front side Z1 than the center in the forward and backward direction Z.

[0035] When viewed from the forward and backward direction Z (illustration omitted), the plate portion 511 is formed around the fixed inner portion 512 over the entire circumference in the circumferential direction. The radially outer end portion of the plate portion 511 is located at a position closer to the radial outside than the electromagnetic coil 53. The radially outer end portion of the plate portion 511 abuts against the front end portion of the outer peripheral portion 622 of the yoke 62.

[0036] In addition, the fixed surface 513 is formed circumferentially around the entire circumference. In this embodiment, the fixed surface 513 is formed at a position radially inward of the winding portion 531 and at a position in front of the winding portion 531 in the Z1 direction. In addition, the fixed surface 513 is formed at a position radially inward of the outer peripheral surface of the yoke portion 61. The fixed surface 513 is formed at a position in front of the front end portion of the sleeve 73 in the Z1 direction. The fixed surface 513 is formed at a position in front of the center of the fixed core portion 51 in the Z direction (the forward and backward direction) in the Z1 direction.

[0037] In addition, the movable core portion 52 is fixed to the shaft 21 in a state where the shaft 21 of the plunger 2 is inserted through the insertion hole formed in the movable core portion 52. Therefore, the movable core portion 52 moves integrally with the shaft 21.

[0038] Next, with reference to Figure 1 , Figure 2 , the operation of the electromagnetic relay 1 of this embodiment will be described. In a state where no power is supplied to the electromagnetic coil 53, no electromagnetic attractive force is generated between the fixed core portion 51 and the movable core portion 52. Therefore, as shown in Figure 1 , the movable core portion 52 is pressed in a direction away from the fixed core portion 51, that is, backward, by the biasing force of the return spring 13. As a result, the movable member 3 mounted on the movable core portion 52 via the shaft 21 and the holding member 22 is in a state of retreating backward, and the movable contact 31 separates from the fixed contact 41.

[0039] When power is supplied to the electromagnetic coil 53 from this state, an electromagnetic attractive force is generated between the fixed core portion 51 and the movable core portion 52. As a result, as shown in Figure 2 , the movable core portion 52 advances against the restoring force of the return spring 13. Along with this, the shaft 21 and the movable member 3 advance. Then, the movable contact 31 abuts against the fixed contact 41. As a result, the electromagnetic relay 1 becomes a connected state. Thereby, current flows from one fixed terminal 40 through the movable member 3 to the other fixed terminal 40. In addition, in this embodiment, the movable core portion 52 advances until the front end portion of the movable core portion 52 abuts against the rear end portion of the fixed core portion 51. That is, the movable core portion 52 further advances from the state where the movable contact 31 abuts against the fixed contact 41. At this time, the shaft 21 fixed to the movable core portion 52 advances, but since the movable contact 31 abuts against the fixed contact 41, the movable member 3 does not advance. Therefore, the shaft 21 also advances relative to the movable member 3, and the contact pressure spring 23 is compressed and deformed. As a result, the elastic force of the contact pressure spring 23 contributes to the contact pressure between the fixed contact 41 and the movable contact 31.

[0040] In addition, if the power supply to the electromagnetic coil 53 is cut off from this Figure 2 state, the electromagnetic attractive force between the fixed core portion 51 and the movable core portion 52 disappears. As a result, the movable core portion 52 retreats due to the restoring force of the return spring 13, asFigure 1 As shown, the movable contact 31 separates from the fixed contact 41, and the electromagnetic relay 1 becomes in an off state.

[0041] In addition, when switching from the connected state to the off state, it does not become in the off state during the period when an arc is generated in the contact portion between the fixed contact 41 and the movable contact 31. Therefore, in order to break this arc, the electromagnetic relay 1 includes an arc extinguishing magnet 14. The arc extinguishing magnet 14 is disposed radially outside the contact portion. The electromagnetic relay 1 is configured such that by this arc extinguishing magnet 14, the arc generated in the contact portion is stretched in a direction orthogonal to the advancing and retreating direction Z to extinguish the arc.

[0042] Next, with reference to Figures 5 to 9 , the manufacturing method of the fixed core portion 51 will be described. As Figure 5 shown, the fixed core portion 51 is manufactured by processing a substantially cylindrical metal member 510 made of a soft magnetic metal. When manufacturing the fixed core portion 51, first, forging processing of the metal member 510 is performed. When performing the forging processing, a fixed jig 191 including a recess 192 into which a part of the metal member 510 is inserted is used. In the fixed jig 191, an opening side curved surface 193 corresponding to the shape of the fixed curved surface 513 is formed in the circumferential direction over the entire circumference between the inner circumferential surface of the recess 192 and the front end surface of the fixed jig 191. Then, as shown by the arrow M in Figure 5 , the metal member 510 is inserted into the recess 192 from the opening side of the recess 192. At this time, as shown in Figure 6 , the metal member 510 is inserted into the recess 192 in such a manner that the rear end surface of the metal member 510 abuts against the bottom surface 194 of the recess 192, but more than half of the metal member 510 projects outside the recess 192. In addition, since the inner diameter of the recess 192 is substantially the same as the outer diameter of the metal member 510, when the metal member 510 is inserted into the recess 192, the inner circumferential surface of the recess 192 and the outer circumferential surface of the metal member 510 are in a state of abutting against each other. In addition, when the metal member 510 is inserted into the recess 192, the opening side curved surface 193 bulges toward the metal member 510 side.

[0043] Next, forging processing is performed by a stamping jig 195. Specifically, as shown by the arrow P in Figure 6 , the metal member 510 is pressed from the side opposite to the fixed jig 191 by the stamping jig 195 to cause it to plastically deform. As a result, as shown in Figure 7As shown, the portion of the metal member 510 exposed outside the recess 192 is deformed into a flat plate shape to form a plate-like portion 515 that becomes a plate portion. Further, when the metal member 510 is pressed by the stamping jig 195, it plastically deforms along the opening-side curved surface 193 of the fixing jig 191. Thereby, a fixing curved surface 513 is formed on the metal member 510. Further, the portion of the metal member 510 disposed inside the recess 192 is a portion that becomes the fixed inner portion 512.

[0044] As Figure 8 shown, the plate-like portion 515 formed by forging has a disc shape. Here, in this embodiment, the plate portion 511 has a substantially rectangular shape when viewed from the advance / retreat direction Z. Therefore, by stamping, the plate-like portion 515 is blanked along the range R indicated by the dashed line in Figure 8 . Thereby, as Figure 9 shown, the plate portion 511 can be formed. Further, although detailed description is omitted, after the plate portion 511 is formed, the metal member 510 is subjected to cutting or forging to form an insertion through-hole 514 or the like, thereby manufacturing the fixing core portion 51 of this embodiment.

[0045] Next, the operation and effect of this embodiment will be described. In the electromagnetic relay 1, the fixed inner portion 512 and the plate portion 511 are integrally formed, and a fixing curved surface 513 is formed between the outer peripheral surface of the fixed inner portion 512 of the fixing core portion 51 and the rear surface of the plate portion 511. Therefore, the connecting portion 516 between the fixed inner portion 512 and the plate portion 511 can easily approach the winding portion 531 of the electromagnetic coil 53. As a result, the magnetic efficiency can be improved.

[0046] Assume that as Figure 10 、 11As shown, assume an electromagnetic relay 9 of Comparative Method 1, in which its fixed core portion 91 and plate portion 92 are separate from each other and do not have a fixed curved surface. The electromagnetic relay 9 of Comparative Method 1 rivets and fixes the plate portion 92 to the fixed core portion 91 including the fixed inner portion 911. In addition, in the electromagnetic relay 9 of Comparative Method 1, at the connecting portion 93 between the fixed core portion 91 and the plate portion 92, the surface of the rear side Z2 of the plate portion 92 is orthogonal to the outer peripheral surface of the fixed core portion 91. In the case of Comparative Method 1, compared with the electromagnetic relay 1 of this method with a fixed curved surface formed, the distance between the connecting portion 93 and the winding portion 531 is likely to become longer. Specifically, considering the assemblability and the arrangement of components such as the sleeve 73 between the electromagnetic coil 53 and the fixed core portion, it is necessary to form a gap 11 between the electromagnetic coil 53 and the fixed core portion 91 and between the electromagnetic coil 53 and the plate portion 92. Therefore, as in Comparative Method 1, when there is a gap 11 and the surface of the rear side Z2 of the plate portion 92 is orthogonal to the outer peripheral surface of the fixed core portion 91 at the connecting portion 93, the distance between the connecting portion 93 and the winding portion 531 is likely to become longer. As a result, compared with the electromagnetic relay 1 of this method, the magnetic efficiency is likely to deteriorate. Therefore, in the electromagnetic relay 1 of this method, the fixed inner portion 512 and the plate portion 511 are integrally formed, and a fixed curved surface 513 is formed on the fixed core portion 51. Thus, compared with Comparative Method 1, it is easy to make the connecting portion 516 between the fixed inner portion 512 and the plate portion 511 and the winding portion 531 approach each other. That is, even if a fixed curved surface 513 is formed on the connecting portion 516, it is not easy to affect the assemblability or the arrangement of components such as the sleeve 73. Therefore, while ensuring the assemblability and the like, the fixed core portion 51 and the winding portion 531 can be made to approach each other. As a result, while ensuring the assemblability, the magnetic efficiency can be improved. In addition, by improving the magnetic efficiency, the number of turns of the wire in the winding portion 531 can be reduced. Therefore, miniaturization of the electromagnetic coil 53 can be achieved, and further miniaturization of the electromagnetic relay 1 can be achieved.

[0047] In addition, as in Comparative Method 1, when the fixed core portion 91 and the plate portion 92 are separate, it is difficult to form a curved surface that bends in a state of protruding toward the plunger 2 side at the connecting portion 93. That is, when trying to form such a curved surface at the connecting portion 93, the shape of at least one of the fixed core portion 91 and the plate portion 92 is likely to become complicated, and the manufacturability is likely to deteriorate. On the other hand, in the electromagnetic relay 1 of this method, since the fixed inner portion 512 and the plate portion 511 are integrally formed, it is easier to form the fixed curved surface 513 compared with the case where the fixed inner portion and the plate portion are separate. As a result, both the magnetic efficiency and the manufacturability can be improved.

[0048] In addition, as Figure 11As shown, in the case of riveting and fixing the plate portion 92 to the fixed core portion 91 as in the electromagnetic relay 9 of Comparison Method 1, a gap 94 may be formed between the plate portion 92 and the fixed core portion 91. Then, since the gap 94 is formed in the magnetic path, the magnetic efficiency is liable to deteriorate. On the other hand, in the case of this method, since the fixed inner portion 512 and the plate portion 511 are integrally formed, there is no gap between the plate portion 511 and the fixed inner portion 512. Therefore, the magnetic efficiency can be improved.

[0049] In addition, in the electromagnetic relay 1 of this method, since the fixed curved surface 513 is formed, the area of the connecting portion 516 is liable to become larger in the cross section including the winding axis C as compared with Comparison Method 1. That is, the magnetic path is liable to become wider as compared with Comparison Method 1. Thereby, the magnetic efficiency can be improved.

[0050] In addition, in this method, the fixed core portion 51 can be formed by forging and stamping. Therefore, the fixed core portion 51 can be easily manufactured. As a result, the manufacturability can be improved.

[0051] In addition, in the electromagnetic relay 1 of this method, since the fixed inner portion 512 and the plate portion 511 are integrally formed, airtightness can be easily ensured. That is, in the case where a gap 94 is formed between the plate portion 92 and the fixed core portion 91 as in Comparison Method 1, gas may flow out from the contact arrangement space 701 to the space where the electromagnetic coil 53 is provided via the gap 94. Therefore, it may not be possible to sufficiently ensure the airtightness of the contact arrangement space 701. In addition, when welding is performed to close the gap 94, the manufacturability is liable to deteriorate. On the other hand, in the case of this method, since the fixed inner portion 512 and the plate portion 511 are integrally formed, it is possible to reliably prevent gas from flowing out from the contact arrangement space 701 to the space where the electromagnetic coil 53 is provided. Therefore, the airtightness of the contact arrangement space 701 can be reliably ensured, and the manufacturability can be improved.

[0052] In addition, a gap 11 is formed between the electromagnetic coil 53 and the fixed core portion 51. Thereby, even when there are dimensional deviations in the respective components, assembly can be reliably performed. Therefore, the assemblability can be ensured. In addition, by forming the gap 11 between the fixed inner portion 512 and the electromagnetic coil 53 in the radial direction, it is easy to dispose the sleeve 73 between the fixed inner portion 512 and the electromagnetic coil 53. Therefore, it is easy to form the core arrangement space 702.

[0053] As described above, according to this method, it is possible to provide the electromagnetic relay 1 that can improve the magnetic efficiency.

[0054] (Embodiment 2) As Figure 12 shown, this method is a method in which the formation range of the fixed curved surface 513 is widened with respect to Embodiment 1.

[0055] In this mode, as Figure 12 shown, in the cross-section of the winding part 531 including the winding shaft C, at least one of the first imaginary straight line L1 and the second imaginary straight line L2 passes through the fixed surface 513. Here, the first imaginary straight line L1 is a straight line that passes through the inner peripheral end of the winding part 531 and is parallel to the advancing and retreating direction Z in the cross-section of the winding part 531 including the winding shaft C. The second imaginary straight line L2 is a straight line that passes through the front end of the winding part 531 and is orthogonal to the advancing and retreating direction Z in the cross-section of the winding part 531 including the winding shaft C. In this mode, in the cross-section of the winding part 531 including the winding shaft C, the first imaginary straight line L1 passes through the fixed surface 513, and the second imaginary straight line L2 does not pass through the fixed surface 513.

[0056] The first imaginary straight line L1 passes through the inner peripheral end of the front winding part 534 which is the part of the winding part 531 that is radially opposite to the fixed inner part 512. In addition, the second imaginary straight line L2 passes through the front end of the front winding part 534. Other structures are the same as those in the first embodiment. In addition, unless otherwise specified, among the symbols used in the embodiments after the second embodiment, the symbols that are the same as those used in the previous embodiments represent the same constituent elements and the like as in the previous embodiments.

[0057] In this mode, in the cross-section of the winding part 531 including the winding shaft C, at least one of the first imaginary straight line L1 and the second imaginary straight line L2 passes through the fixed surface 513. Therefore, the distance between the connecting part 516 and the winding part 531 can be further shortened. As a result, the magnetic efficiency can be further improved. Except for this, it has the same effects as those in the first embodiment.

[0058] (Third Embodiment) As Figure 13 shown, this mode is a mode in which the formation range of the fixed surface 513 is widened relative to the second embodiment.

[0059] In this mode, as Figure 13 shown, in the cross-section including the winding shaft C, both the first imaginary straight line L1 and the second imaginary straight line L2 pass through the fixed surface 513. Other structures are the same as those in the second embodiment.

[0060] In this mode, in the cross-section including the winding shaft C, both the first imaginary straight line L1 and the second imaginary straight line L2 pass through the fixed surface 513. Therefore, the distance between the connecting part 516 and the winding part 531 can be further shortened. As a result, the magnetic efficiency can be further improved. Except for this, it has the same effects as those in the second embodiment.

[0061] (Embodiment 4) As Figure 14 shown, this embodiment is an embodiment in which the thickness of the bobbin 532 is reduced compared to Embodiment 3.

[0062] As Figure 14 shown, the thickness T1 of the cylindrical portion 533 of the bobbin 532 is thinner than the thickness T3 of the plate portion 511. The thickness T1 is 1 / 2 or less of the thickness T3. Additionally, the thickness T1 is 1 / 3 or less of the thickness T3.

[0063] In addition, the bobbin 532 has a front eave portion 535 extending radially outward from the front end of the cylindrical portion 533. The front eave portion 535 covers the winding portion 531 from the front side Z1. The front eave portion 535 is formed in a ring shape. The thickness T2 of the front eave portion 535 is thinner than the thickness T3. The thickness T2 is 1 / 2 or less of the thickness T3. Additionally, the thickness T2 is 1 / 3 or less of the thickness T3. Other structures are the same as those in Embodiment 3.

[0064] The thickness T1 is 1 / 2 or less of the thickness T3. Therefore, the fixed core portion 51 and the winding portion 531 are more easily accessible. As a result, the magnetic efficiency can be further improved.

[0065] The thickness T2 is 1 / 2 or less of the thickness T3. Therefore, the fixed core portion 51 and the winding portion 531 are more easily accessible. In addition, since the thickness T2 is relatively thin, the length of the winding portion 531 can be increased in the forward and backward direction Z. Therefore, the number of turns of the wire can be increased. As a result, the magnetic efficiency can be further improved. In addition to this, it has the same effects as those in Embodiment 3.

[0066] The present disclosure is not limited to the above-described embodiments, and can be applied to various embodiments without departing from the gist thereof.

[0067] Although the present disclosure has been described based on the embodiments, it should be understood that the present disclosure is not limited to the above-described embodiments and structures. The present disclosure also includes various modification methods and modifications within the equivalent range. In addition, various combinations and methods, and further other combinations and methods including only one element, more than one element, or less than one element thereof also belong to the scope and the scope of the idea of the present disclosure.

Claims

1. An electromagnetic relay (1), comprising: A movable member (3) having a movable contact (31) that contacts and separates from a fixed contact (41); A plunger (2) that moves the movable member forward and backward to cause the fixed contact and the movable contact to contact and separate; and A solenoid section (5) that moves the plunger forward and backward, The solenoid section having: An electromagnetic coil (53) including a winding section (531) formed by winding a wire, and forming a magnetic flux (φ) by energizing the winding section; A fixed core section (51) including an insertion through-hole (514) through which the plunger is inserted, and a part of which is disposed inside the electromagnetic coil; and A movable core section (52) disposed at a position rearward (Z2) of the fixed core section and fixed to the plunger, The fixed core section and the movable core section constitute a magnetic path of the magnetic flux formed by energizing the winding section, The movable core section moves forward and backward relative to the fixed core section as the winding section is energized, The fixed core section has a plate section (511) disposed at a position forward (Z1) of the electromagnetic coil and formed to overlap the electromagnetic coil when viewed in the advancing and retreating direction (Z) of the plunger, The plate section is integrally formed with a fixed inner section (512) of the fixed core section disposed inside the electromagnetic coil, A gap (11) is formed between the electromagnetic coil and the fixed core section, In the fixed core section, a fixed curved surface (513) that is curved in a state of protruding toward the plunger side is formed between the outer peripheral surface of the fixed inner section and the rear surface of the plate section.

2. The electromagnetic relay according to claim 1, characterized in that In a cross-section of the winding section including the winding axis (C), at least one of a first imaginary straight line (L1) passing through the inner peripheral end of the winding section and parallel to the advancing and retreating direction and a second imaginary straight line (L2) passing through the front end of the winding section and orthogonal to the advancing and retreating direction passes through the fixed curved surface.

3. The electromagnetic relay according to claim 2, characterized in that In a cross-section including the winding axis, both the first imaginary straight line and the second imaginary straight line pass through the fixed curved surface.

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