The application is based upon and claims the benefit of priority of Japanese Patent Application No. 2014-98936, filed on May 12, 2014, the entire contents of which are incorporated herein by reference.
The present invention generally relates to contact devices and in particular relates to a contact device such as an electromagnetic relay.
Document 1 (e.g., JP 2013-80692 A) discloses an electromagnetic relay exemplifying a conventional example. This conventional example includes a base, an electromagnetic block, an armature, a movable contact member, and a fixed contact member. The electromagnetic block, the movable contact member, and the fixed contact member are attached to the base made of synthetic resin material.
In the conventional example, when the base made of synthetic resin material is deformed in molding, a positional relationship between parts such as the electromagnetic block may be changed undesirably, and this may cause a decrease in reliability.
In view of the above insufficiency, the present invention has aimed to improve reliability.
The contact device of one aspect of the present invention includes: an armature; a driver for driving the armature; a fixed contact; a movable contact to be in contact with and separate from the fixed contact; a contact spring for holding the movable contact so as to allow movement of the movable contact; a card interconnecting the armature and the contact spring; a case being a synthetic resin molded product; and a positioning member provided as a separate part from the case. The positioning member is for determining a positional relationship between the armature, the driver, the fixed contact, the movable contact, the contact spring, and the card, and is accommodated in the case.
Hereinafter, the contact device (electromagnetic relay) of one embodiment in accordance with the present invention is described in detail with reference to attached drawings. Note that, the contact device of the present invention is not limited to the present embodiment, and may have various configurations within the technical scope of the present invention. Unless otherwise noted, the following descriptions are made based on forward and rearward, left and right, and upward and downward directions defined in
As shown in
Note that, there is a tiny flange 110 protruding inward from the almost entire periphery of an opening of the cover 11. The bottom of the body 10 is caught by the flange 110, and therefore the body 10 and the cover 11 are coupled so that separation of the body 10 and the cover 11 is prevented (see
Further, the contact device of the present embodiment includes a relay body A which is constituted by a driving block, a contact block, and a positioning member 12 and is situated in the case 1.
The driving block includes a driver 2, an armature 8, a hinge spring 9, and a card 13. The driver 2 is an electromagnet including a bobbin 21, a coil 20 formed by winding a wire around the bobbin 21, an iron core situated in a center of the bobbin 21, and a heel piece 22.
The bobbin 21 includes a barrel inside the coil 20, a first flange 210 provided to one axial end of the barrel, and a second flange 211 provided to the other axial end of the barrel. Note that, in this bobbin 21, it is preferable that the barrel and the pair of flanges 210 and 211 be formed integrally by use of insulating material such as synthetic resin.
The first flange 210 is in a flat rectangular box shape with one open bottom (right side) and one open side (lower face) (see
The heel piece 22 is in an L shape, and includes a holding piece 220 held by the second flange 211, and a main piece 221 extending from an end of the holding piece 220 to the first flange 210 which are formed integrally by use of magnetic material (see
The armature 8 includes a driving piece 80 in a band plate shape, and a supporting piece 81 which is in a flat plate shape and is wider than the driving piece 80. The driving piece 80 and the supporting piece 81 are formed integrally by use of magnetic material. The supporting piece 81 is accommodated in the first flange 210, and is fixed to a first fixing piece 90 of the hinge spring 9 (see
The driving piece 80 protrudes to an outside of the first flange 210 through the open side (lower face) of the first flange 210. Further, the driving piece 80 abuts on a front end of the main piece 221 of the heel piece 22 (see
The hinge spring 9 includes the first fixing piece 90, a second fixing piece 91, and a pair of spring pieces 92. The first fixing piece 90, the second fixing piece 91, and the pair of spring pieces 92 are formed integrally by use of a plate spring (see
When the armature 8 is driven by the driver 2, the armature 8 turns around a fulcrum defined by a part of the armature 8 in contact with the main piece 221 of the heel piece 22, in a direction (counterclockwise in
The contact block includes a fixed contact 3, a movable contact 4, a first terminal 5, a second terminal 6, and a contact spring 7.
The contact spring 7 includes multiple (three in the present embodiment) plate springs 70 and an interconnection member 71 (see
The interconnection member 71 includes an attachment part 710 in a rectangular shape, an inclined part 711 protruding obliquely downward from a center of a lower end of the attachment part 710, and a connection piece 712 extending from a front end (lower end) of the inclined part 711 in parallel with the attachment part 710 (see
The attachment part 710 is situated on the attachment pieces 702 of the plate springs 70. The movable contact 4 is provided to a surface (right side) of the attachment part 710 so as to penetrate through the three attachment pieces 702 and the attachment part 710. Further, in the connection piece 712, a front end (lower end) part is wider than a remaining part. The connection piece 712 is coupled to the card 13 at the wide front end part.
Further, the contact spring 7 is connected to the second terminal 6 at a further end part (upper end of the main piece 700) of the plate spring 70 (see
The fixing piece 61 is in a rectangular flat plate shape, and the further end (upper end) of the plate spring 70 of the contact spring 7 is fixed (swaged) to the fixing piece 61. The inclined piece 62 is in a rectangular flat plate shape, and extends obliquely downward (in a left lower direction) from the lower end of the fixing piece 61. The interconnection piece 63 is in a rectangular flat plate shape, and interconnects the upper end of the terminal piece 60 and the lower end of the inclined piece 62.
The fixed contact 3 which is to be in contact with the movable contact 4 is provided to the first terminal 5. The first terminal 5 includes a terminal piece 50, an attachment piece 51, a supporting piece 52. and an interconnection piece 53, which are formed integrally by use of metal. The terminal piece 50 is in a rectangular flat plate shape, and includes a screw hole 500 penetrating through its center. A terminal screw is screwed into the screw hole 500.
The attachment piece 51 is in a rectangular flat plate shape, and the fixed contact 3 is attached to a center of the attachment piece 51. The supporting piece 52 includes: a main piece 520 having the front end connected to the terminal piece 50; and an inclined piece 521 extending obliquely upward from the upper edge of the main piece 520. The interconnection piece 53 is in a rectangular flat plate shape, and interconnects the upper end of the inclined piece 521 and the right end of the attachment piece 51.
The card 13 of the driving block is made of resilient material (e.g., a metal plate), and is fixed to each of the armature 8 and the contact spring 7.
The card 13 is in a band shape as shown in
As shown in
The bottom wall 120 is in a flat hook shape. The first longitudinal wall 121 to the fifth longitudinal wall 125 are in an almost rectangular flat plate shape, and extend in the same direction from a surface of the bottom wall 120. The first longitudinal wall 121, the second longitudinal wall 122, and the third longitudinal wall 123 are arranged in parallel with each other at intervals on a narrow part of the bottom wall 120.
Note that, a space between the first longitudinal wall 121 and the second longitudinal wall 122 is defined as a first groove 126, and a space between the second longitudinal wall 122 and the third longitudinal wall 123 is defined as a second groove 127. The fourth longitudinal wall 124 and the fifth longitudinal wall 125 are arranged in parallel with each other at an interval on an end of a broad part of the bottom wall 120. Note that, a space between the fourth longitudinal wall 124 and the fifth longitudinal wall 125 is defined as a third groove 128.
Further, with regard to the bottom wall 120, a pair of holding holes (first holding holes) 1260 are arranged in a length direction of the first groove 126 in a bottom of the first groove 126. Further, with regard to the bottom wall 120, a pair of holding holes (second holding holes) 1270 are arranged in a length direction of the second groove 127 in a bottom of the second groove 127. Furthermore, with regard to the bottom wall 120, a pair of holding holes (third holding holes) 1280 are arranged in a length direction of the third groove 128 in a bottom of the third groove 128.
Each of the pair of first holding holes 1260, the pair of second holding holes 1270, and the pair of third holding holes 1280 is a rectangular through hole penetrating through the bottom wall 120. Note that, protrusions are provided to an inner circumferential surface of each of the first holding holes 1260, the second holding holes 1270, and the third holding holes 1280.
The main piece 221 of the heel piece 22 constituting the driver 2 is inserted into the first groove 126. This main piece 221 includes a pair of protrusions. The pair of protrusions are pressed into the first holding holes 1260, and thereby the main piece 221 of the heel piece 22 is held and positioned in the first groove 126 (see
Further, the interconnection piece 53 of the first terminal 5 is inserted into the second groove 127. The interconnection piece 53 also includes a pair of protrusions 530 (see
Further, the interconnection piece 63 of the second terminal 6 is inserted into the third groove 128. The interconnection piece 63 also includes a pair of protrusions. The pair of protrusions are pressed into the third holding holes 1280, and thereby the interconnection piece 63 of the second terminal 6 is held and positioned in the third groove 128 (see
In summary, the positioning member 12 is configured to define a positional relationship between the armature 8, the driver 2, the fixed contact 3, the movable contact 4, the contact spring 7, and the card 13. Further, the driver 2, the first terminal 5, and the second terminal 6 are held by the positioning member 12 to constitute the relay body A.
There are rectangular holes 101A and 101B penetrating through left and right corners of a lower part of a bottom plate 100 of the body 10 respectively. Further, there are multiple protrusions provided to an inner circumferential surface of the left hole 101A. A rear end part of the interconnection piece 63 of the second terminal 6 is inserted into the left hole 101A. Further, a rear end part of the main piece 520 of the first terminal 5 is inserted into the right hole 101B. In short, the relay body A is accommodated in the body 10 while the rear end of the interconnection piece 63 of the second terminal 6 is supported on the body 10 (see
Further, when the relay body A is accommodated in the body 10, the coil terminals 212 of the driver 2 protrude to an outside of the body 10 through a groove 102 provided to an upper side plate of the body 10 (see
In the body 10, there is an arc extinguishing member placed inside a space surrounded by the driver 2, the armature 8, contacts (the fixed contact 3 and the movable contact 4), and the card 13. The arc extinguishing member is constituted by a permanent magnet 14 and a yoke 15. The permanent magnet 14 is in a rectangular flat plate shape, and is magnetized to have different poles in a thickness direction. In the forward and rearward direction, the yoke 15 is in an L shape. The permanent magnet 14 and the yoke 15 are accommodated in an accommodation part 104 provided to the body 10.
The accommodation part 104 is in a box shape whose outer shape is an L shape in the forward and rearward direction, and protrudes forward from the bottom plate 100 of the body 10 (see
Next, a process of assembling the contact device of the present embodiment is briefly described.
First, the fixing part 131 of the card 13 is engaged with the connection piece 712 of the contact spring 7, and thereafter the driver 2, the first terminal 5, and the second terminal 6 are held by the positioning member 12. Thereafter, the hole 130 of the card 13 is engaged with the projection 82 of the armature 8, and thereby the relay body A is assembled.
Subsequently, the relay body A is accommodated in the body 10. At this time, the rear end part of the interconnection piece 63 of the second terminal 6 is pressed into the hole 101A of the bottom plate 100 of the body 10, and thereby the relay body A is positioned and fixed to the body 10. Further, by covering the cover 11 with the body 10 from front, the case 1 is assembled. At last, the permanent magnet 14 and the yoke 15 are accommodated in the accommodation part 104 of the body 10, and thereby assembling of the contact device of the present embodiment is completed.
Note that, there are cut-outs 111 formed in left and right side walls of the cover 11 to allow the terminal piece 50 of the first terminal 5 and the terminal piece 60 of the second terminal 6 to protrude outside (see
Next, operation of the contact device of the present embodiment is described with reference to
While no voltage is applied between the coil terminals 212, the driver 2 does not operate the armature 8. Therefore, the contact spring 7 is not pulled by the card 13, and the movable contact 4 and the fixed contact 3 face each other to form a predetermined gap therebetween. At this time, the first terminal 5 and the second terminal 6 are in a non conduction state (off-state).
In contrast, while a voltage is applied between the coil terminals 212, the driver 2 operates the armature 8, and the armature 8 rotates counterclockwise. Therefore, the contact spring 7 is pulled by the card 13 and is bent in a right direction. Therefore, the movable contact 4 is in contact with the fixed contact 3. At this time, the first terminal 5 and the second terminal 6 are in a conduction state (on-state).
Note that, when a voltage is not applied between the coil terminals 212 in the on-state, the armature 8 rotates clockwise, and the contact device returns to the off-state.
When the contact returns from the on-state to the off-state, arc discharge may occur between the movable contact 4 and the fixed contact 3. When arc discharge occurs, it is necessary to extinguish the resultant arc in order to end arc discharge in short time.
In view of this, the contact device of the present embodiment accommodates, in the accommodation part 104 of the body 10, the arc extinguishing member constituted by the permanent magnet 14 and the yoke 15. In more details, the permanent magnet 14 and the yoke 15 form a magnetic field around the fixed contact 3 and the movable contact 4, and thereby an arc is elongated by electromagnetic force caused by the magnetic field, and this results in extinguishment of the arc.
As described above, the contact device of the present embodiment positions parts such as the armature 8 and the driver 2 by use of the positioning member 12 provided as a separate part from the case 1. Even if the case 1 (especially, the body 10) is deformed in molding (e.g., due to mold shrinkage), the positional relationship between the parts is unlikely to be changed. Therefore, the contact device of the present embodiment can offer improvement of the reliability relative to the conventional example.
Further, in the contact device of the present embodiment, it is preferable that the positioning member 12 be accommodated in the case 1 so as not to be in contact with the case 1. If the positioning member 12 is separate from the case 1, the positioning member 12 can be hardly influenced by deformation of the case 1
Additionally, it is preferable that the positioning member 12 be made of synthetic resin material (e.g., PES (Poly Ether Sulfone) resin) which is hardly deformed in molding (e.g., mold shrinkage). However, such synthetic resin material is more expensive than synthetic resin material which is more easily deformed in molding.
In view of this, it is preferable that the case 1 and the positioning member 12 be made of different synthetic resin materials. If the case 1 is made of inexpensive synthetic resin material (e.g., PBT (Poly Butylene Terephthalate) resin) which is different material from the positioning member 12, the total production cost can be lowered.
Moreover, it is preferable that the case 1 include a positioning part for positioning any part whose positional relation is determined by the positioning member 12. In the contact device of the present embodiment, the second terminal 6 (the interconnection piece 63) is pressed into the hole 101A of the bottom plate 100 of the body 10 and thereby positioned. In summary, the hole 101A serves as the positioning part, and the second terminal 6 serves as a part to be positioned by the positioning part. If the case 1 is configured like above, the relay body A can be hardly influenced by deformation of the case 1.
Note that, in the contact device of the present embodiment, the positioning member 12 may include at least one of: a protrusion engaged with a recess provided to the case 1; and a recess engaged with a protrusion provided to the case 1. For example, as shown in
The recess 1220 of the second longitudinal wall 122 is engaged with the protrusion 113 of the cover 11, and the recess 1200 of the bottom wall 120 is engaged with the protrusion 105 of the body 10 (see
Note that, in the contact device, normally, noise (operation noise) occurs when the driver drives the movable contact member by use of the armature. If the electromagnetic block (driver) is directly held by the base (outer casing) as with the conventional example disclosed in document 1, vibration (impact) occurring when the armature and the movable contact member are driven by the electromagnetic block (driver) is easily transferred to the base (outer casing), and therefore there is a problem that it is difficult to reduce operation noise.
However, in the contact device of the present embodiment, the positioning member 12 which is provided as a separate part from the case 1 holds parts such as the armature 8 and the driver 2. Therefore, vibration occurring when the armature 8 is driven by the driver 2 is not transferred to the case 1 directly. Hence, in contrast to a case where vibration occurring when the armature 8 is driven by the driver 2 is transferred to the case 1 directly like the conventional example, the contact device of the present embodiment can reduce operation noise.
Additionally, it is preferable that the positioning member 12 be a synthetic resin molded product. In more detail, when the positioning member 12 is made of synthetic resin material, the vibration caused by operation can be buffered, and the operation noise can be reduced.
Note that, the positioning member 12 may be made of material other than synthetic resin material, such as rubber and metal. For example, the positioning member 12 made of rubber can be higher in noise suppression properties than the positioning member 12 made of synthetic resin material. Alternatively, the operation noise in a case where the positioning member 12 is made of metal becomes higher in frequency than in a case where the positioning member 12 is made of synthetic resin material, and therefore a tone of the operation noise can be changed.
Further, it is preferable that the case 1 be configured to hold at least one of the first terminal 5 and the second terminal 6. In the contact device of the present embodiment, the case 1 (the body 10) is configured to hold the second terminal 6. Therefore, the relay body A is positioned in the case 1 and a path of transfer of the vibration to the case 1 is increased. Hence, the vibration is less likely to be transferred to the case 1, and thus the operation noise can be reduced.
Moreover, it is preferable that the case 1 be in a rectangular box shape and hold at least one of the first terminal 5 and the second terminal 6 by use of any of corners of the case. In the contact device of the present embodiment, the second terminal 6 is held at one corner (the hole 101A provided to a corner of the bottom plate 100) of the case 1 (body 10).
It is considered that vibration of the entire case 1 in a case where vibration is transferred through a corner of the bottom plate 100 may be more suppressed than in in a case where vibration is transferred through a central part of the bottom plate 100. Hence, by holding the second terminal 6 by the corner of the case 1, the operation noise can be reduced. Note that, the first terminal 5 may be held by the case 1 instead of the second terminal 6, or the first terminal 5 and the second terminal 6 may be held by the case 1.
Furthermore, it is preferable that at least one of the driver 2 and the positioning member 12 be accommodated in the case 1 so as not to be in contact with a central part of the case 1. In the contact device of the present embodiment, each of the driver 2 and the positioning member 12 is accommodated in the case 1 so as not to be in contact with the central part of the case 1. In this case, the driver 2 and the positioning member 12 are not in contact with the central part of the case 1 which may allow occurrence of relatively large noise when it transfers the vibration. Hence, the vibration is less likely to be transferred to the case 1, and thus the operation noise can be reduced.
Note that, as shown in
It is preferable that the reinforcing member 16 be constituted by a first protruding wall 160 protruding forward (upward in
When the case 1 is assembled by coupling the body 10 and the cover 11 with each other, the protrusion 1610 is engaged with the recess 1600, and the first protruding wall 160 and the second protruding wall 161 are coupled with each other, and thereby the reinforcing member 16 is formed. Alternatively, the reinforcing member may be an integral part formed by fixing the cover 11 and the accommodation part 104 to each other by a method such as bonding.
When the case 1 of the contact device of the present embodiment is configured like above, vibration of the case 1 can be suppressed and operation noise can be reduced. However, the above configuration of the reinforcing member 16 is only example, and the configuration of the reinforcing member 16 is not limited to the configuration illustrated in
As described above, the contact device of the first aspect in accordance with the present invention includes an armature 8, a driver 2, a fixed contact 3, a movable contact 4, a contact spring 7, a card 13, a case 1, and a positioning member 12. The driver 2 is for driving the armature 8. The movable contact 4 is to be in contact with and separate from the fixed contact 3. The contact spring 7 is for holding the movable contact 4 so as to allow movement of the movable contact 4. The card 13 interconnects the armature 8 and the contact spring 7. The case 1 is a synthetic resin molded product. The positioning member 12 is provided as a separate part from the case 1. The positioning member 12 is for determining a positional relationship between the armature 8, the driver 2, the fixed contact 3, the movable contact 4, the contact spring 7, and the card 13, and is accommodated in the case 1.
In the contact device of the second aspect in accordance with the present invention, realized in combination with the first aspect, the positioning member 12 is a synthetic resin molded product.
In the contact device of the third aspect in accordance with the present invention, realized in combination with the first or second aspect, the positioning member 12 is accommodated in the case 1 so as not to be in contact with the case 1.
In the contact device of the fourth aspect in accordance with the present invention, realized in combination with the second or third aspect, the case 1 and the positioning member 12 are made of different synthetic resin materials.
In the contact device of the fifth aspect in accordance with the present invention, realized in combination with any one of the first to fourth aspects, the case 1 includes a positioning part (hole 101A) for positioning any part (the second terminal 6) whose positional relation is determined by the positioning member 12.
In the contact device of the sixth aspect in accordance with the present invention, realized in combination with the first or second aspect, the positioning member 12 includes at least one of: a protrusion engaged with a recess provided to the case 1; and a recess (recess 1220, 1200) engaged with a protrusion (protrusion 113, 105) provided to the case 1.
In the contact device of the seventh aspect in accordance with the present invention, realized in combination with any one of the first to sixth aspects, the contact device further includes a first terminal 5 which holds the fixed contact 3 and is positioned by the positioning member 12, and a second terminal 6 which holds the contact spring 7 and is positioned by the positioning member 12. The case 1 holds at least one of the first terminal 5 and the second terminal 6.
In the contact device of the eighth aspect in accordance with the present invention, realized in combination with the seventh aspect, the case 1 is in a rectangular box shape, and holds at least one of the first terminal 5 and the second terminal 6 by use of any of corners of the case.
In the contact device of the ninth aspect in accordance with the present invention, realized in combination with any one of the first to eighth aspects, at least one of the driver 2 and the positioning member 12 is accommodated in the case 1 so as not to be in contact with a central part of the case 1.
In the contact device of the tenth aspect in accordance with the present invention, realized in combination with any one of the first to ninth aspects, the case 1 includes:
a pair of walls (the bottom plate 100 of the body 10 and the front wall of the cover 11) facing each other with the driver 2 and the positioning member 12 in-between; and a reinforcing member 16 interconnecting the pair of walls.
In the contact device of the eleventh aspect in accordance with the present invention, realized in combination with any one of the first to tenth aspects, the card 13 is more flexible in a direction perpendicular to a contact and separation direction of the movable contact 4 than in the contact and separation direction.
In the contact device of the twelfth aspect in accordance with the present invention, realized in combination with any one of the first to eleventh aspects, the card 13 is made of metal.
Number | Date | Country | Kind |
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2014-098936 | May 2014 | JP | national |
Number | Name | Date | Kind |
---|---|---|---|
5216397 | Matsuoka | Jun 1993 | A |
5392015 | Matsuoka | Feb 1995 | A |
20020130741 | Noguchi | Sep 2002 | A1 |
20070013467 | Mikl | Jan 2007 | A1 |
20100117769 | Kuo | May 2010 | A1 |
20130082806 | Moriyama | Apr 2013 | A1 |
Number | Date | Country |
---|---|---|
1744340 | Jan 2007 | EP |
2187418 | May 2010 | EP |
2811470 | Jan 2002 | FR |
2013-080692 | May 2013 | JP |
Entry |
---|
European Search Report dated Oct. 7, 2015 issued in European Patent Application No. 15167240.9. |
Number | Date | Country | |
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20150325399 A1 | Nov 2015 | US |