Electromagnetic relay

Abstract

The present disclosure provides an electromagnetic relay having high insulating properties while minimizing an increase in size and the number of components. The electromagnetic relay includes: an electromagnet having a coil, a bobbin around which the coil is wound, an iron core inserted into the bobbin, and a yoke cooperating with the iron core to form a magnetic circuit; a movable terminal having a movable contact that operates in accordance with the operation of the electromagnet; a fixed terminal having a fixed contact disposed facing the movable contact; a coil terminal attached to the bobbin and connected to the coil; an insulating member disposed between the coil and the yoke; and a base having a wall that insulates between the coil terminal and the fixed terminal.

Description

Technical Field

[0001] The present invention relates to an electromagnetic relay (relay). Background Art

[0002] An electromagnetic relay is configured to open and close contacts by passing current through a coil. Among them, there is a hinge type relay having: a yoke connected to an iron core; and an armature configured to be movable relative to the yoke.

[0003] In a relay having a coil and a yoke, a technique is known in which an insulating member is disposed between the coil and the yoke to insulate the two members. In addition, a technique is known in which a flange portion is provided on a bobbin around which a coil is wound to increase the insulation distance between the coil and an electronic component.

[0004] Prior Art Documents

[0005] Patent Documents

[0006] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2014-049315

[0007] Patent Document 2: Japanese Unexamined Patent Application Publication No. 2017-027877

[0008] Patent Document 3: Japanese Unexamined Patent Application Publication No. 2009-009710

[0009] Patent Document 4: Japanese Unexamined Patent Application Publication No. 2023-051496

[0010] Patent Document 5: Japanese Unexamined Patent Application Publication No. 2023-051497

[0011] Patent Document 6: Japanese Unexamined Patent Application Publication No. 2023-051498

[0012] In relays for low-voltage applications, the requirements regarding the electrical insulation performance between components are relatively low. However, for relays for high-voltage / high-current applications such as in-vehicle chargers for electric vehicles, high insulation performance is required. As methods for improving insulation performance, there are methods of increasing the physical distance between components or disposing insulating members between components. However, the former has the problem of increasing the size of the relay, and the latter has the problem of increasing the number of parts. Summary of the Invention

[0013] Therefore, a relay is desired that minimizes the increase in size and the number of parts and achieves high insulation.

[0014] One embodiment of the present disclosure is a relay having: an electromagnet including a coil, a bobbin around which the coil is wound, an iron core inserted into the bobbin, and a yoke that cooperates with the iron core to form a magnetic circuit; a movable terminal having a movable contact that operates with the operation of the electromagnet; a fixed terminal having a fixed contact disposed opposite to the movable contact; a coil terminal assembled to the bobbin and connected to the coil; an insulating member disposed between the coil and the yoke; and a base having a wall that insulates between the coil terminal and the fixed terminal. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is a perspective view of the electromagnetic relay of the embodiment.

[0016] Figure 2 is Figure 1 an exploded perspective view of the electromagnetic relay.

[0017] Figure 3 is a perspective view showing a structural example of the insulating member.

[0018] Figure 4 is a view when observing the insulating member of Figure 3 from another angle.

[0019] Figure 5 is a cross-sectional view taken along line A-A of Figure 3 the [object].

[0020] Figure 6 is a cross-sectional view taken along line A'-A' of Figure 1 the [object].

[0021] Figure 7 is a cross-sectional view taken along line A''-A'' of Figure 6 the [object].

[0022] Figure 8 is a view showing an example of the connection manner between the bobbin and the insulating member.

[0023] Figure 9 is a view showing an example of the riveting position of the yoke relative to the movable spring.

[0024] Figure 10 is a perspective view showing the state after combining the bobbin and the insulating member.

[0025] Figure 11 is a perspective view showing a structural example of the bobbin.

[0026] Figure 12 is a view when observing the bobbin of Figure 11 from another angle.

[0027] Figure 13 Viewed from the front-rear direction Figure 11 of the bobbin.

[0028] Figure 14 Viewed from the width direction Figure 11 of the bobbin.

[0029] Figure 15 Viewed from the height direction Figure 11 of the bobbin.

[0030] Figure 16 Is a perspective view showing a structural example of the base.

[0031] Figure 17 View of the base when viewed from the height direction.

[0032] Figure 18 Is along Figure 17 A cross-sectional view of the F-F line.

[0033] Figure 19 Is a perspective view of an electromagnetic relay composed of 1a contacts. Detailed implementation mode

[0034] Figure 1 Is a perspective view of the electromagnetic relay (relay) 10 of the implementation mode, Figure 2 Is Figure 1 Exploded perspective view. The relay 10 is used for, for example, a vehicle-mounted charger, and has a base 12 and an electromagnet 20 assembled to the base 12. The electromagnet 20 has: a bobbin (winding frame) 14; a coil 16 wound around the bobbin 14; an iron core 18 disposed inside the bobbin 14; and a substantially L-shaped yoke (magnetic yoke) 22, which is combined with one end of the iron core 18 and forms a magnetic circuit together with the iron core 18. In addition, the relay 10 has: an armature 25, which is attracted to the head, which is the other end of the iron core 18, as the electromagnet 20 operates; a movable terminal 26, which has two movable contacts 24 and moves in a direction of contacting / separating from the head of the iron core 18 corresponding to the movement of the armature 25; and two coil terminals 28, which are connected to both ends of the coil winding 16. In the illustrated example, the coil terminals 28 are assembled to the bobbin 14. In addition, the movable contact 24 is assembled near the tip of the movable spring.

[0035] Relay 10 has fixed terminals, and the fixed terminals have fixed contacts disposed opposite to the movable contact 24. Relay 10 is a so-called 1c-contact relay, and has a first fixed terminal (open terminal) 32 having two fixed open contacts 30 and a second fixed terminal (closed terminal) 36 having two fixed closed contacts 34 as the fixed terminals. In the illustrated example, the first fixed terminal 32 and the second fixed terminal 34 are respectively assembled to the coil bobbin 14. The movable contact 24 contacts the fixed normally closed contact 30 when the electromagnet 20 is off, and contacts the fixed normally open contact 34 when the electromagnet 20 is on. By each of the movable terminal 26, the open terminal 32, and the closed terminal 36 having two contacts, a relay 10 with high conduction performance is obtained. Relay 10 can be automatically assembled using an assembly machine or the like, or can be assembled by manual operation.

[0036] Relay 10 has: a cover 38 configured to be fitted to the base 12 and accommodate the above-described components together with the base 12; and an insulating member 40 configured to electrically insulate between the coil 16 and the yoke 22. To clarify the components of relay 10, Figure 1 the cover 38 is omitted in the figure. The base 12, the coil bobbin 14, the cover 38, and the insulating member 40 among the above-described components are made of an electrically insulating resin material and can be formed by injection molding, for example.

[0037] In the present embodiment, the height direction parallel to the axial direction of the iron core 18 is referred to as the z direction, the width direction perpendicular to the z direction and in which two movable contacts 24 or two fixed contacts 30 or fixed contacts 34 are arranged is referred to as the y direction, and the direction perpendicular to both the y direction and the z direction is referred to as the x direction.

[0038] Figure 3 is a perspective view showing a structural example of the insulating member 40, Figure 4 is a perspective view when observing the insulating member 40 from a direction Figure 3 different from the above, Figure 5 is a cross-sectional view along the Figure 3 A - A line in the figure. In addition, Figure 6 is a cross-sectional view along the Figure 1 A'-A' line parallel to the z direction in the figure, Figure 7 is a cross-sectional view along the Figure 6 A''-A'' line perpendicular to the z direction in the figure.

[0039] The insulating member 40 has: a wall 42 disposed between the coil 16 and the yoke 22 and extending in a substantially z direction; a fitting portion 44 provided at a lower portion of the wall 42, i.e., on a side opposite to the contact, for fitting the lower flange portion 48 of the bobbin 14; and an eaves 46 provided at an upper portion of the wall 42 to cover the upper flange portion 50 of the bobbin 14. The insulating member 40 further has a protruding portion 52 extending from the wall 42 in a substantially tangential direction of the coil 16.

[0040] The insulating member 40 is fixed to the bobbin 14 by inserting the lower flange portion 48 into the fitting portion 44 by pressing or the like. The fitting portion 44 is defined by the lower surface of the protruding portion 52 and a bottom portion 54 formed at a position spaced below the protruding portion 52. At this time, preferably, in order to smoothly fit the lower flange portion 48 into the fitting portion 44, as Figure 5 shown, the lower end 53 of the protruding portion 52 has a tapered shape that narrows in width from the right side to the left side in the direction perpendicular to the z direction in the drawing. In addition, preferably, the bottom portion 54 and the lower end 53 respectively have ribs 56 for guiding the lower flange portion 48 when it is inserted. As Figure 8 shown, the lower flange portion 48 inserted into the fitting portion 44 is clamped by the ribs 56 disposed above and below it, so that the fitting portion 44 and the lower flange portion 48 can be more reliably fixed by the ribs 56.

[0041] As Figure 6 and Figure 7 shown, by disposing the insulating member 40 of the present embodiment between the coil 16 and the yoke 22, the insulation distances d1 and d2 between the coil 16 and the yoke 22 or the armature 25 can be significantly extended as compared with the insulation distance d3 when it is assumed that there is no insulating member 40. In addition, as Figure 7 shown, by the insulating member 40 having the protruding portion 52, the insulation distance d7 between the coil 16 and the movable terminal 26 can be significantly extended as compared with the insulation distance d8 when it is assumed that there is no protruding portion 52.

[0042] As Figure 8 shown, alternatively, in order to make the fitting between the insulating member 40 and the bobbin 14 more firm, a concave fitting portion 71 is formed on the bobbin 14 side, and a tapered portion 58 as shown in Figure 3 and Figure 4 is formed on the bottom portion 54 of the insulating member 40.

[0043] The insulating member 40 only contacts the bobbin 14 at the fitting portion 44 and does not contact the upper flange portion 50 of the bobbin 14. Therefore, the eaves 46 of the insulating member 40 has the function of covering the upper flange portion 50 to increase the insulation distance between the coil 16 and the yoke 22, but does not contact the upper flange portion 50. For example, as Figure 5As shown, alternatively, in order to more reliably prevent the eaves 46 from contacting the upper flange portion 50, the eaves 46 have a tapered shape with a tip that tapers as it moves away from the wall 42.

[0044] Except for the fitting portion 44, the insulating member 40 does not contact the bobbin 14. Therefore, when assembling the relay 10, the insulating member 40 does not slide relative to other members except for the fitting portion 44 and the lower flange portion 48. In a relay, during the press-fitting / sliding between members during assembly, debris and the like may sometimes be generated, and sometimes obstacles may occur in the opening and closing operation of the contacts due to the debris. However, in the present embodiment, by positioning the portions where debris such as that caused by sliding may be generated away from the contacts, the amount of debris generated is suppressed, and the generated debris does not adversely affect the operation of the relay. In this way, the insulating member 40 contacts the bobbin 14 only at the lower part of the relay 10. On the other hand, the movable contact and the fixed contact are provided at the upper part of the relay 10. Therefore, even if debris is generated at the lower part of the relay, it is possible to reduce the entry of debris between the movable contact and the fixed contact provided at the upper part of the relay, which may be a main factor causing malfunction of the relay.

[0045] When winding the winding forming the coil 16 around the bobbin 14, the lower flange portion 48 or the upper flange portion 50 may sometimes warp. Therefore, if a structure in which both the lower flange portion 48 and the upper flange portion 50 are fixed to other members is adopted, the bobbin may interfere with other members during assembly, making the assembly difficult. However, in the present embodiment, a structure is adopted in which the upper flange portion 50 does not contact other members and has a gap. Therefore, even if there is warping, interference between the upper flange portion 50 and other members can be prevented.

[0046] As described above, the insulating member 40 is fitted to the bobbin 14 at the fitting portion 44. Therefore, it is desirable that the lower part of the insulating member 40 does not deform during molding. Therefore, it is desirable that the wall thickness of the portion of the insulating member 40 that forms the fitting portion 44 is constant. By making the wall thickness constant, for example, deformation during injection molding can be suppressed.

[0047] When the yoke 22 is formed by bending a metal plate, the bent yoke 22 may contact the insulating member 40. Therefore, as Figure 5 shown, it is preferable that the insulating member 40 has a retracted portion 60 to avoid contact with the portion of the yoke 22 corresponding to the inner R of the bend.

[0048] As Figure 9As illustrated by way of example, in the assembly of the relay 10, when the movable spring 62 is riveted to the yoke 22 at position 27, it is sometimes necessary to insert a jig into the back side of the yoke 22 corresponding to position 27. However, depending on the shape of the insulating member, it is sometimes difficult or impossible to insert the jig. Therefore, as Figure 3 and Figure 4 show, the insulating member 40 preferably has a recess 64 on the side where the protruding portion 52 faces the yoke 22. In Figure 7 , the insulating member 40 having the recess 64 has a substantially C-shaped form in a plan view, and a space for inserting the jig can be ensured between the insulating member 40 and the yoke 22.

[0049] As Figure 6 shows, the eaves 46 have a shape protruding in the x direction and toward the contact side (right side in Figure 6 ) so as to increase the insulation distance between the coil 16 and the yoke 22. Here, further as shown in the B portion of Figure 10 , the eaves 46 may also have an extension portion 66 that protrudes in the y direction compared to the upper flange portion 50 of the bobbin 14 within a range where it does not contact the cover 38. With the extension portion 66, the insulation distance between the coil 16 and the yoke 22 can be further extended.

[0050] The insulating member 40 preferably has a structure that prevents malfunction of the relay 10 and facilitates assembly. For example, as Figure 8 shows, preferably, the upper end surface 68 of the eaves 46 is located slightly lower than the upper end 70 of the bobbin 14 and on the side opposite to the contact in the z direction. When the upper end surface 68 extends above the upper end 70, the armature 25 may contact the upper end surface 68 during operation, resulting in malfunction of the relay 10. However, by configuring it as in Figure 8 , contact between the armature 25 and the upper end surface 68 can be prevented. In addition, the lower end surface 72 of the bottom portion 54 is preferably located slightly higher than the lower end 74 of the bobbin 14 and on the contact side in the z direction. In this way, when assembling the relay 10, contact between the yoke 22 and the lower end surface 72 can be avoided, and the assembly becomes easier.

[0051] Figure 11 is a perspective view showing a structural example of the bobbin 14, Figure 12 is a perspective view of the bobbin 14 when viewed from a direction different from Figure 11 . In addition, Figure 13 - Figure 15 are respectively the front view when viewed along the direction C parallel to the x direction, the side view when viewed along the direction D parallel to the y direction, and the bottom view when viewed along the direction E parallel to the z direction of the bobbin 14 in Figure 11 .

[0052] The bobbin 14 has: a hollow cylindrical main body portion 47 around which the coil 16 is wound; and a lower flange portion 48 and an upper flange portion 50 provided at both ends of the main body portion 47 in the long dimension direction. In the state where the relay 10 is assembled, the lower flange portion 48 is received in the base 12, the main body portion 47 extends in the z direction with respect to the base 12, and the upper flange portion 50 is disposed above the base 12 and substantially parallel to the lower flange portion 48. The lower flange portion 48 and the upper flange portion 50 are each substantially rectangular plate-like members extending from the main body portion 47 in a direction perpendicular to its substantially long dimension direction and parallel to the xy plane.

[0053] As described above, the lower flange portion 48 is fitted into the insulating member 40 by being pressed into the fitting portion 44 or the like. Therefore, the lower flange portion 48 preferably has a tapered portion 76 that facilitates insertion into the fitting portion 44. In addition, as Figure 12 and Figure 15 shown, the lower flange portion 48 of the bobbin 14 preferably has a tapered portion 78 that abuts against the tapered portion 58 for guiding, so as to easily insert the tapered portion 58 into the fitting portion 71.

[0054] The lower flange portion 48 has functions such as preventing the winding of the coil 16 from coming off, fixing the insulating member 40, and ensuring the insulation distance between the coil 16 and the yoke 22. Here, in order to further extend the insulation distance between the coil 16 and the yoke 22 and between the coil 16 and the armature 25, the lower flange portion 48 may have a stepped portion 80 that extends forward in the x direction toward the yoke 22. Similarly, the upper flange portion 50 may also have a stepped portion 82 that extends forward in the x direction toward the yoke 22. By the stepped portions 80 and 82 extending in the x direction, the insulation distances d1 and d2 as Figure 6 shown can be further extended.

[0055] In addition, as Figure 13 - Figure 14 shown, the lower flange portion 48 may also have a wall 84 for ensuring the insulation distance between the coil 16 and the yoke 22. By the wall 84, a longer insulation distance d4 between the coil 16 and the yoke 22 can be ensured compared to the case where there is no wall 84 as Figure 6 shown.

[0056] Figure 16 is a perspective view showing a structural example of the base 12, Figure 17 is a perspective view when observing the base 12 from above in the z direction, Figure 18 is along Figure 17A cross-sectional view of the F-F line in []. The base 12 has: a frame portion 86 that extends with a substantially rectangular outline when viewed from above; and a bottom portion 90 that partially encloses an opening 88 defined by the lower end of the frame portion 86. The base 12 is configured to accommodate the components of the relay 10 and fix them in a predetermined position.

[0057] Formed in the bottom portion 90 of the base 12 are: a first hole 92 through which Figure 2 the movable terminal 26 as described in [] is inserted; a second hole 94 through which the coil terminal 28 is inserted; and a third hole 96 through which the fixed terminals 32 and 36 are inserted. In addition, the base 12 has a wall 98 for ensuring an insulation distance between the coil terminal 28 and the fixed terminals 32 and 36. The wall 98 extends upward in the z direction from the bottom portion 90 and has a substantially U shape when viewed from above. The wall 98 is adjacently disposed to the third hole 96 in a manner that does not interfere with the assembly of other components.

[0058] As Figure 6 shown, by providing the wall 98, an insulation distance d5 longer than the insulation distance d6 assumed when there is no wall 98 between the coil terminal 28 and the fixed terminal 36 can be ensured. In addition, when viewed from above, since the shape of the wall 98 is substantially U-shaped, as Figure 7 shown, a relatively long insulation distance d9 can be ensured between the coil terminal 28 and the fixed terminal 36.

[0059] The wall 98 can be integrally formed as a part of the base 12 by injection molding of resin or the like. Therefore, even if the wall 98 is provided, the number of parts of the relay 10 is not increased. In addition, there is no need to enlarge the base 12 in order to form the wall 98. Therefore, according to the present embodiment, a relay 10 is provided that can ensure a relatively long insulation distance between the coil terminal 28 and the fixed terminal 36 without being accompanied by enlargement or an increase in the number of parts.

[0060] As Figure 18 shown, the wall 98 may also have a tapered guide portion 100 that facilitates the insertion of the fixed terminal 36 when assembling the relay 10. The guide portion 100 also has a function of improving the positioning accuracy of the fixed terminal 36.

[0061] In the above example, the relay 10 having a so-called 1c contact configuration with a disconnect terminal 32 having a fixed contact has been described, but the application object of the present disclosure is not limited thereto. For example, the present disclosure can be similarly applied to a relay 10' as Figure 19 shown, which has a so-called 1a contact configuration with a rear blocking portion 104 instead of the disconnect terminal, and the rear blocking portion 104 does not have a fixed contact.

[0062] According to the present disclosure described above, it is possible to provide a relay that can suppress an increase in the number of components, achieve miniaturization of the relay, and insulate each part.

Claims

1. A relay having: The electromagnet comprises a coil, a coil frame around which the coil is wound, an iron core inserted into the coil frame, and a yoke forming a magnetic circuit together with the iron core. A movable terminal having a movable contact that moves as the electromagnet operates; A fixed terminal having a fixed contact arranged opposite to the movable contact; A coil terminal, mounted on the coil frame and connected to the coil; An insulating member, disposed between the coil and the yoke; as well as The base has a wall for insulating the coil terminal from the fixed terminal.

2. The relay according to claim 1, wherein: The insulating member has a fitting portion to be fitted with a lower flange portion of the coil bobbin, and the insulating member is in contact with the coil bobbin only at the fitting portion.

3. The relay according to claim 2, wherein: At least one of the upper flange portion and the lower flange portion of the coil bobbin has a step portion extending toward the yoke.

4. The relay according to claim 2, wherein: The insulating member has a constant thickness at a portion constituting the fitting portion.

5. The relay according to claim 1, wherein: The insulating member has a protruding portion extending in a tangential direction of the coil, and the insulating member has a recessed portion on a side of the protruding portion facing the yoke.

6. The relay according to claim 1, wherein: An upper end surface of the insulating member in the axial direction of the core is located on the side opposite to the contact point in the axial direction of the core, compared to an upper end of the coil bobbin.

7. The relay according to claim 1, wherein: A lower end surface of the insulating member in the axial direction of the core is located closer to the contact point than a lower end of the coil bobbin in the axial direction of the core.

8. The relay according to claim 1, wherein: The insulating member has a protruding portion extending in a substantially tangential direction of the coil, and a lower end of the protruding portion has a tapered shape whose width becomes narrower toward the core side in a direction perpendicular to an axial direction of the core.

9. The relay according to claim 1, wherein: The insulating member has an eave that covers an upper flange portion of the coil bobbin and does not contact the upper flange portion.

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