Relay

Abstract

To provide a relay with shock resistance and easy to assemble.SOLUTION: A base 48 has a leg 80 extending a contact direction, and the leg 80 is configured to come into contact with a yoke 72 when the base 48 is assembled within a case 22. The leg 80 is arranged with a spaced above an armature 60. The space is set to a value such that, in the normal operation of armature 60, the top surface of armature 60 does not come into contact with the leg 80, but when a vehicle equipped with a relay 10 receives a strong impact and when armature 60 jumps beyond its range of motion, the upper surface of the armature 60 comes into contact with the lower surface of leg 80.SELECTED DRAWING: Figure 11

Description

Technical Field

[0001] The present invention relates to a relay.

Background Art

[0002] A relay (electromagnetic relay) is configured to open and close contacts by passing a current through a coil, and there is a hinge-shaped relay having an armature (yoke) connected to an iron core and a contact pole (armature) movably configured with respect to the armature.

[0003] In recent years, relays are increasingly being used in applications that are prone to impacts and vibrations, such as being mounted on electric vehicles. In order to prevent displacement of the armature with respect to the yoke when a large impact or vibration is applied to the relay, a technique is known in which a shaft portion is provided on one of the yoke or the armature, and a bearing for rotatably receiving the shaft portion is provided on the other, making the armature rotatable with respect to the yoke.

[0004] An assembly structure of a relay is known in which a contact holder groove opened on the side surface of an insulating substrate is formed, a fixed contact and a movable contact are inserted into the holding groove and locked and held, and then the periphery of the lead-out portion of the external terminal is sealed with an adhesive. A relay terminal block is known in which a groove for mounting components is provided on the body with an opening on the side surface, components such as terminal components are inserted through the opening and attached to the body, and a cover plate covering the opening is attached to the body.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Summary of the Invention

Problems to be Solved by the Invention

[0006] In many relays, leaf springs or coil springs are used to generate appropriate contact force and separation force for opening and closing contacts. When such a relay is used in an application that is susceptible to shock and vibration, the spring may undergo plastic deformation due to the shock, and there is a risk that appropriate contact force and separation force cannot be obtained. On the other hand, if a reinforcing member or the like for withstanding shock is provided separately, the assembly work of the relay becomes complicated and may lead to an increase in cost.

[0007] Therefore, an object of the present invention is to provide a relay that is resistant to shock and vibration and is easy to assemble.

Means for Solving the Problems

[0008] One aspect of the present disclosure is Comprising a bobbin and a core disposed on the bobbin an electromagnet, A yoke disposed on the core, an armature swingably supported on the yoke and displaced toward the core according to the on / off of the electromagnet, and a movable contact portion having a movable contact that operates in response to the operation of the electromagnet, a fixed contact portion having a fixed contact disposed opposite to the movable contact, and a case that houses the electromagnet and the movable contact portion. According to the displacement of the accompanying armature The case has a structure that opens in the contact separation direction, and the fixed contact portion constitutes a lid portion of the case, and is a relay. The displacement direction of the armature and the contact / separation direction between the fixed contact and the movable contact are different from each other, The case The has a structure that opens in the contact separation direction, and the fixed contact portion constitutes a lid portion of the case, and is a relay.

Advantages of the Invention

[0009] According to the present disclosure, by configuring the leg portion of the base to which the fixed terminal is attached to extend in the contact separation direction between the fixed contact and the movable contact and abut against the yoke, and to be disposed at a predetermined interval above the armature, in addition to improving the positioning accuracy between the fixed contact portion and the electromagnet, an effect of preventing damage, plastic deformation, etc. of each part due to shock or the like can also be obtained.

Brief Description of the Drawings

[0010]

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Embodiments for Carrying Out the Invention

[0011] FIGS. 1 and 2 are an assembled view and an exploded perspective view of a relay (electromagnetic relay) 10 according to an embodiment, respectively. The relay 10 is, for example, a relay for in-vehicle electrical equipment used in an electric vehicle. The relay 10 is a hinge-shaped relay having a fixed contact portion 14 including a fixed contact 12 (see FIG. 8), a movable contact portion 18 including a movable contact 16, an electromagnet 20 for displaceably moving the movable contact 16 relative to the fixed contact 12, and a case 22 for housing the movable contact portion 18 and the electromagnet 20. The relay 10 is mounted on a printed circuit board (not shown) using a metal collar 24 attached to the outside of the case 22 by caulking or the like.

[0012] As shown in FIG. 2, the movable contact portion 18 and the electromagnet 20 (collectively also referred to as the "main body 21" of the relay) are inserted and incorporated into the case 22 by moving them along the contact-making and breaking direction of the fixed contact 12 and the movable contact 16 (substantially the left-right direction in FIG. 2) with respect to the case 22. Therefore, the case 22 can have a structure that opens only in the contact-making and breaking direction, and for example, there is no need to have a structure in which parts divided into two in the up-down direction are combined. The fixed contact portion 14 includes a base 48 and a fixed contact 12 provided on the base 48. By inserting the fixed contact portion 14 into the case 22, the back surface of the fixed contact portion 14 constitutes the lid of the relay 10. The relay 10 is sealed by filling the boundary between the fixed contact portion 14 and the case 22 with resin or an adhesive. The case 22 can be made, for example, by resin molding. By forming the case 22 as described above, the number of parts can be reduced and the manufacturing cost can be lowered.

[0013] FIG. 3 and FIG. 4 are a perspective view and a front view, respectively, showing the inside of the case 22. The case 22 has ribs 26 and 28 for guiding and positioning the movable contact portion 18 and the electromagnet 20 at predetermined positions within the case 22. Each rib extends in the contact separation direction of the contacts and in the mounting direction of the main body 21 to the case 22.

[0014] FIG. 5 is a schematic cross-sectional view showing the positional relationship between the armature 60, the yoke 72, which are components of the electromagnet 20, and each rib when the electromagnet 20 is disposed in the case 22. The rib 26 formed on the inner bottom surface of the case 22 abuts against the lower surface of the yoke 72, supports the movable contact portion 18, and contributes to the vertical positioning of the movable contact portion 18. The rib 28 formed on the inner side surface of the case 22 has an inclined surface 29 that is inclined in the insertion direction of the main body 21, and the inclined surface 29 functions as a guide in the width direction of the yoke 72 when the main body 21 is inserted into the case 22. After the main body 21 is inserted, the rib 28 abuts against the side surface of the yoke 72 and contributes to the accurate positioning of the electromagnet 20 in the width direction with respect to the case 22.

[0015] The rib 30 formed on the upper surface within the case 22 is disposed at a vertical interval from the armature 60 and does not contact the armature 60 during normal operation. However, even if the armature 60 bounces greatly beyond the movable range when the vehicle on which the relay 10 is mounted receives a strong impact or the like, the movement of the armature 60 is suppressed by the rib 30, and it is possible to prevent a large force from acting on the contacts and a return spring described later. Therefore, by providing the rib 30, it is possible to prevent damage to each part and plastic deformation of the spring.

[0016] FIG. 6 shows the back side of the case 22, i.e., the side opposite to the opening into which the main body 21 is inserted. As shown in FIGS. 2 and 9, the electromagnet 20 has two coil terminals 78 for supplying power to the coil 68. The coil terminals 78 are inserted into a vertically long opening 41 (see FIGS. 3 and 4) formed inside the case 22 and are exposed outside the case 22 through an opening 32 formed in the back surface of the case 22. The opening 32 has a space for routing electric wires 34 and 36 respectively connected to the two coil terminals 78. After the electric wires 34 and 36 are introduced into a pocket 38 formed in the outer portion of the case 22, they are drawn out from an opening 40 of the pocket 38 that opens upward and are electrically connected to a printed circuit board (not shown) on which the relay 10 is mounted.

[0017] FIG. 7 shows a state in which after the electric wires 34 and 36 are drawn out from the opening 40, the opening 32 is filled and sealed with a resin or an adhesive 42. In this way, the back surface of the case 22 will not have the electric wires 34 and 36 or members related thereto protruding, and thus a compact relay can be constructed with respect to the contact making and breaking direction. It is preferable to provide air holes 44 in the case 22 to discharge the air expanded inside the case 22 when a thermosetting resin or an adhesive is used. The air holes 44 are preferably sealed with a resin or the like after the opening 32 is sealed.

[0018] FIG. 8 is an exploded perspective view of the fixed contact portion 14 and the movable contact portion 18. The fixed contact portion 14 has at least one (two in the illustrated example) fixed terminals 46 each having a fixed contact 12 and a frame-shaped or box-shaped base 48 to which the fixed terminals 46 are attached. A resin or an adhesive is filled between the fixed terminals 46 and the base 48 to seal the gap. The base 48 is made, for example, by resin molding. A permanent magnet 50 and a permanent magnet yoke 54 are attached to the outer surface of the base 48, and an arc extinguishing plate 52 for extinguishing an arc is inserted into the base 48, which will be described later.

[0019] The movable contact portion 18 includes a conductive plate 56 to which the movable contact 16 is attached by caulking or the like, a movable spring 58 to which the conductive plate 56 is attached, and an armature 60 to which the movable spring 58 is attached by a rivet 62 or the like.

[0020] FIG. 9 shows an exploded perspective view of the electromagnet 20 together with the case 22. The electromagnet 20 includes a bobbin 70, a core 66 disposed within the bobbin 70, a coil 68 wound around the bobbin 70, a substantially L-shaped yoke 72 to which the lower end of the core 66 is coupled, and a spring post 74 attached to the yoke 72. The bobbin 70 has a terminal port 76 into which the coil terminal 78 is inserted, and current flows through the coil 68 via the electric wires 34, 36, and the coil terminal 78. The armature 60 is supported so as to be swingable with respect to the yoke 72. As will be described later, the movable spring 58 and the spring post 74 are elastically displaceably connected to each other via a return spring 64 (see FIG. 8).

[0021] FIGS. 10 and 11 are a top view and a side view of the fixed contact portion 14 and the movable contact portion 18, respectively, and FIG. 12 is a perspective view of the base 48. The base 48 has legs 80 extending in the mounting direction of the main body to the case 22. As shown in part A of FIGS. 10 and 11, the end face of the leg 80 is configured to contact the yoke 72 when the base 48 is incorporated into the case 22. Therefore, the positional relationship in the contact separation direction of the contact between the fixed contact portion 14 and the electromagnet 20 is uniquely determined, and accurate positioning between the members within the case 22 becomes possible.

[0022] As can be seen from FIG. 13 showing the cross section taken along line B-B' in FIG. 10, the leg portion 80 is disposed above the armature 60 with a space therebetween. This space is set such that in the normal operation of the armature 60, the upper surface of the armature 60 does not contact the lower surface of the leg portion 80, but when the vehicle on which the relay 10 is mounted receives a strong impact or the like and the armature 60 bounces up beyond its movable range, the upper surface of the armature 60 comes into contact with the lower surface of the leg portion 80. Conventional relays do not include a member for suppressing large displacements due to the lifting or the like of the armature 60. Therefore, a large force is applied in the direction of stretching the return spring 64 due to the displacement of the armature 60, and there is a risk that the return spring 64 will undergo plastic deformation. In this embodiment, the movement of the armature 60 beyond its normal movable range is suppressed by the leg portion 80, the force applied to the contact points and the return spring 64 is reduced, and plastic deformation of the return spring 64 is also prevented. That is, in addition to improving the positioning accuracy between the fixed contact portion 14 and the electromagnet 20, the leg portion 80 also has a function of preventing damage, plastic deformation, etc. of each part due to impact or the like. The leg portion 80 can be integrally formed with the base 48 by resin molding or the like, and in such a case, the number of parts does not increase.

[0023] FIG. 14 is a side sectional view of the movable contact portion 18 and the electromagnet 20, FIG. 15 is a perspective view showing the structure of the spring post 74, and FIG. 16 is a perspective view showing a structural example of the movable spring 58. The return spring 64 shown in FIG. 14 is a coil spring, but it may be constituted by a leaf spring or the like. One end of the return spring 64 is engaged and held in a recess 86 formed at the base of a tip portion 84 formed substantially at the center in the width direction of the spring post 74 fixed to the yoke 72. The other end of the return spring 64 is engaged and held in a recess 94 formed at the base of a protrusion 92 formed on the movable spring 58. When the electromagnet 20 is off, the armature 60 is inclined to move away from the iron core 66 by the biasing force of the return spring 64, and the movable contact 16 is in a state separated from the fixed contact 12 (FIG. 14). On the other hand, as shown in FIG. 17, when the electromagnet 20 is on, the armature 60 is displaced toward the iron core 66 by magnetic force against the biasing force of the return spring 64, and the movable contact 16 is in a state of contacting the fixed contact 12.

[0024] If a strong impact or external force acts on the relay 10 in the separating direction of the movable contact 16 (the left-right direction in FIG. 14), the movable contact 16 and the conductive plate 56 may be greatly displaced toward the yoke 72. As a result, the movable spring 58 may be plastically deformed. In this embodiment, this problem can be prevented by extending the tip 84 of the spring post 74 to the movable contact side in the contact separating direction rather than the yoke 72. Even if the movable contact 16 is displaced toward the yoke 72 due to an impact or the like, the further displacement of the movable spring 58 is suppressed when the movable spring 58 or the conductive plate 56 abuts against the tip 84, and damage or plastic deformation of the movable spring 58 is prevented. Since the tip 84 is provided on a return spring post for attaching a return spring, it is not necessary to provide a separate member for suppressing the displacement of the movable spring, and the number of parts can be suppressed.

[0025] In the case of a relay that directly engages one end of the return spring with the yoke 72, since no member is interposed between the conductive plate and the yoke, it is impossible to prevent the large displacement of the conductive plate toward the yoke side. However, the spring post 74 according to this embodiment has a tip 84 that suppresses the displacement of the conductive plate 56 in the left-right direction in addition to the function of holding the return spring 64, and thus has a function of preventing plastic deformation of the movable spring 58 due to a large external force or the like in the contact separating direction.

[0026] When miniaturization of the relay is required, it is preferable that the distance between the yoke 72 and the conductive plate 56 be short. Therefore, in this embodiment, as shown in FIG. 9 or FIG. 14, a recess or an opening 96 is formed in the yoke 72 so that a part of the spring post 74 is disposed in the opening 96. As shown in FIG. 15, the spring post 74 has a base 87 fixed to the yoke 72, a first bent portion 88 bent in a direction extending from the base 87 into the opening 96, and a second bent portion 90 bent in a direction opposite to the bending direction of the first bent portion 88 from the first bent portion 88, and the tip 84 is provided at the second bent portion 90. By configuring such that a part of the spring post 74 is disposed in the opening 96, the distance that the spring post 74 extends from the yoke 72 toward the movable contact 16 side can be minimized, and miniaturization of the relay can be achieved. Further, since the spring post 74 has two bent portions 88 and 90 bent in opposite directions to each other, elastic deformation is possible in the contact separation direction of the contacts, and damage and plastic deformation of the spring post 74 are prevented.

[0027] When vibrations at a frequency equal to the natural frequency of the movable part of the hinge-type relay are applied to the relay, resonance of the movable part may occur. For example, when vibrations at a frequency equal to the natural frequency of the movable contact portion 18 are applied to the relay 10, resonance in the contact separation direction between the movable contact 16 and the fixed contact 12 occurs, and there is a risk that the relay 10 may malfunction, such as the movable contact 16 coming into contact with the fixed contact 12 in an unintended situation.

[0028] Therefore, in this embodiment, when the movable contact 16 is in the neutral position as shown in FIG. 14 (when the relay 10 is not operating), the distance d1 in the contact separation direction between the tip 84 and the movable spring 58 or the conductive plate 56 is set to be smaller than the distance d2 (see FIG. 14) between the fixed contact 12 and the movable contact 16. Since d1 is smaller than d2, even if the movable contact portion 18 vibrates due to resonance, the movable spring contacts the return spring post before the amplitude becomes large, and it is possible to suppress the amplitude from becoming larger. Therefore, it is possible to prevent the fixed contact 12 and the movable contact 16 from coming into contact unintentionally due to resonance. Thus, the spring post 74 having the above-described dimensional relationship can prevent malfunction of the relay during resonance of the movable part.

[0029] In relays, particularly in DC relays to which a high voltage such as 400 to 800 V is applied, means for extending or extinguishing an arc to protect the contacts, specifically, a permanent magnet and an arc extinguishing plate are provided. Since these means were attached to a member separate from an arc extinguishing chamber or the like having an arc extinguishing function, they were factors increasing the component cost and the assembly man-hours.

[0030] Therefore, in this embodiment, as shown in FIGS. 8 and 18, the base 48 is formed in a frame shape or a box shape by resin molding or the like. The base 48 has a concave portion 100 on the side surface into which the permanent magnet 50 is fitted, a slot 102 into which the arc extinguishing plate 52 is inserted, and an outer surface 104 to which the permanent magnet yoke 54 is attached. The base 48 illustrated in FIGS. 8 and the like is integrally molded.

[0031] FIG. 19 shows a state in which the permanent magnet 50, the arc extinguishing plate 52, and the yoke 54 are attached to the base 48, and FIG. 20 shows a state in which the base 48 is omitted from illustration for clarity from FIG. 19. In this way, the yoke 54, the permanent magnet 50, and the arc extinguishing plate 52 can all be attached to the base 48 to which the fixed contact 12 is attached. Therefore, the base 48 also functions as an arc extinguishing chamber having high arc interruption performance, having the permanent magnet 50, the yoke 54, and the arc extinguishing plate 52 surrounding the fixed contact 12.

[0032] FIG. 21 is a side cross-sectional view of the base 48, and illustrates how the arc is extended and extinguished by the permanent magnet 50, the arc extinguishing plate 52, and the yoke 54. Due to the magnetic flux from the permanent magnet 50 and the yoke 54, the arc 106 generated between the fixed contact 12 and the movable contact 16 is extended into the arc extinguishing chamber of the base 48. The two permanent magnets 50 preferably have the same poles on the surfaces facing each other. With such an arrangement of the same poles facing each other, the arc generated between the contacts can be extended in the same direction.

[0033] FIG. 22 shows, as a comparative example, the state of the arc when the arc extinguishing plate 52 is not present. As can be seen from FIG. 21, the arc 106 is extended by the arc extinguishing plate 52 inserted into the base 48. On the other hand, in FIG. 22 where the arc extinguishing plate 52 is not provided, the arc spreads within the base 48 without being extended. In this way, by attaching all the members related to arc extinction to the base 48 where a space for arc extinction is secured, a relay with a high arc interruption ability is provided without increasing the number of parts.

[0034] This embodiment is a so-called double-break type relay. Since two fixed contacts 12 are attached to the base 48, it is preferable to arrange a permanent magnet or an arc extinguishing plate at a position as close as possible to each fixed contact. Therefore, in this embodiment, two permanent magnets 50 are attached to both side surfaces of the base 48, and two arc extinguishing plates 52 are inserted and arranged in the base 48 so as to extend up to the vicinity of the two fixed contacts 12 respectively. Also, the yoke 54 is configured to be divided into two parts vertically so that it can be attached from the vertical direction of the base 48 from the viewpoint of ease of assembly and the like, but it is not limited to this. For example, it may be configured to be divided into two parts horizontally so that it can be attached from the horizontal direction of the base 48.

[0035] FIG. 23 is an exploded perspective view of the fixed contact portion 14'. The fixed contact portion 14' is different from FIG. 8 in that a magnetic shield 110 made of a material with a high magnetic permeability such as iron is arranged at a fixed portion (the pedestal 109 of the base 48 in the illustrated example) between the two fixed contacts 12. The other components are the same as those in FIG. 8, and the same reference numerals are given and detailed description is omitted.

[0036] FIG. 24 is a view showing a state where the base 48 is not illustrated. FIG. 24 shows the permanent magnet 50, the arc extinguishing plate 52, the yoke 54, and the magnetic shield 110 arranged between the two fixed contacts 12. In this embodiment, in addition to the arc extinguishing function, the magnetic flux absorption function described below can also be obtained.

[0037] FIG. 25 is a diagram for explaining the relationship between the current flowing through the fixed contact 12 and the magnetic flux, and FIG. 26 shows the relationship between the current and the magnetic flux when there is no magnetic shield 110 as a comparative example. For example, when using a relay as a DC relay, the current input to one of the fixed terminals 46 in the direction of arrow 112 flows from the other fixed terminal 46 in the direction of arrow 114 via the fixed contact 12, the movable contact 16, the conductive plate 56, and the other fixed contact 12. Due to the current flowing in this way, a magnetic flux 116 perpendicular to the paper surface and from the back to the front direction is generated between the two fixed contacts 12 and the fixed terminals 46. When a large current is applied to the closed contacts of the relay, an electromagnetic repulsive force may occur between the movable contact and the fixed contact, which may cause the contacts to open or weld together.

[0038] When there is no magnetic shield 110 as shown in FIG. 26, the influence of the magnetic flux 116 extends to the range indicated by the broken line 120, for example, and a Lorentz force in the direction indicated by the arrow 122 acts on the conductive plate 56 within the range 120. Therefore, in the example of FIG. 26, a force in the contact opening direction is applied to the conductive plate 56, and there is a risk that the fixed contact 12 and the movable contact 16 may be separated by the Lorentz force.

[0039] On the other hand, when the magnetic shield 110 is provided as shown in FIG. 25, since the magnetic flux is absorbed by the magnetic shield 110, it is possible to prevent a force in the contact opening direction from being generated on the conductive plate 56 due to the influence of the magnetic flux. Therefore, according to this embodiment, a relay that is less likely to malfunction is provided, especially when a large current flows.

[0040] The magnetic shield 110 is arranged on a fixed part such as the base 48, not on the movable part of the relay 10. Although it is also possible to arrange the magnetic shield on the movable part, generally, when the weight of the movable part increases, there is a tendency that malfunction is likely to occur when an impact or the like is applied to the relay. Therefore, it is preferable to avoid arranging the magnetic shield on the movable part. In this embodiment, since the magnetic shield is arranged on the fixed part, the weight of the movable part does not increase due to the magnetic shield, and such a problem can also be prevented.

Explanation of reference numerals

[0041] 10 relay, 12 fixed contact, 14 fixed contact part, 16 movable contact, 18 movable contact part, 20 electromagnet, 22 case, 26, 28, 30 rib, 32 opening, 34, 36 wire, 38 pocket, 40 opening, 42 adhesive, 46 fixed terminal, 48 base, 50 permanent magnet, 52 arc extinguishing plate, 54 permanent magnet yoke, 56 conductive plate, 58 movable spring, 60 armature, 64 return spring, 72 yoke, 74 spring post, 78 coil terminal, 80 leg part, 84 tip part, 88, 90 bending part, 92 protrusion, 96 opening, 106, 108 arc, 109 pedestal, 110 magnetic shield

Claims

1. An electromagnet including a bobbin and a core disposed on the bobbin, a yoke disposed on the core, an armature swingably supported on the yoke and displaced toward the core according to the on / off state of the electromagnet, and a movable contact portion having a movable contact that operates according to the displacement of the armature accompanying the operation of the electromagnet, a fixed contact portion having a fixed contact disposed opposite to the movable contact, a case that houses the electromagnet and the movable contact portion, and the displacement direction of the armature and the contact / separation direction between the fixed contact and the movable contact are different from each other, the case has a structure that opens in the contact / separation direction, the fixed contact portion constitutes a lid portion of the case, a relay.

2. The relay according to claim 1, wherein the yoke has an L shape, the core is connected to one end side of the yoke, and the armature is supported on the other end side of the yoke.

3. The relay according to claim 2, wherein the movable contact portion has a movable spring attached to the armature and a conductive plate attached to one end of the movable spring, and the movable contact is attached to the conductive plate.

4. The relay according to claim 3, wherein a plurality of the movable contacts are attached to the same conductive plate, and the fixed contacts are provided in the same number as the movable contacts.

5. The relay according to claim 1, wherein a rib that extends in the housing direction of the movable contact portion into the case and abuts against the side surface of the yoke is formed on the inner surface of the case.

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