The present invention relates to a contact device.
A contact device includes a fixed contact and a movable contact. The movable contact moves between a closed position where the movable contact contacts the fixed contact and an open position where the movable contact is separate from the fixed contact. When the movable contact separates from the fixed contact, an arc is generated between the contacts. Conventionally, as described in Japanese Laid-Open Patent Publication No. 2015-49939, there is known a contact device including an arc extinguishing member disposed in a space where the contacts are housed in order to quickly extinguish an arc. The arc extinguishing member discharges an arc extinguishing gas by utilizing heat of the arc. The arc extinguishing gas extinguishes the arc, thereby improving breakdown performance of the contact device.
In order to improve arc extinguishing performance owing to the arc extinguishing gas, it is desirable that the arc extinguishing member is disposed proximate to a gap between the fixed contact and the movable contact. However, if the arc extinguishing member is disposed proximate to the gap between the contacts, a space between the arc extinguishing member and the contacts becomes narrow. Thus, the arc is less likely to pass through the space and stays. This makes it difficult for the arc to be extinguished quickly.
An object of the present invention is to improve the arc extinguishing performance owing to the arc extinguishing gas.
A contact device according to one aspect of the present invention includes a fixed contact, a movable contact, a housing, and an arc extinguishing member. The movable contact moves between a closed position where the movable contact contacts the fixed contact and an open position where the movable contact is separate from the fixed contact. The housing houses the fixed contact and the movable contact. The arc extinguishing member is movably disposed in the housing and discharges an arc extinguishing gas. The arc extinguishing member is disposed facing a gap between the fixed contact and the movable contact when the movable contact is in the open position.
In the contact device according to the present aspect, the arc extinguishing member is movably disposed in the housing. Therefore, when the arc extinguishing gas is generated, the arc extinguishing gas causes an increase in pressure, whereby the arc extinguishing member moves. Thus, even if the arc extinguishing member is disposed proximate to the gap, a large space can be secured between the contacts and the arc extinguishing member. Accordingly, an arc extinguishing gas can be generated proximate to the gap between the contacts and an arc can easily pass through a space between the contacts and the arc extinguishing member. As a result, the arc is easily extended and quickly extinguished. Therefore, the arc extinguishing performance owing to the arc extinguishing gas can be improved.
The arc extinguishing member may be configured to move at least in a direction in which the arc extinguishing member separates from the fixed contact. In this case, the arc extinguishing member can move toward the direction in which the arc extinguishing member separates from the fixed contact due to the pressure increase caused by the arc extinguishing gas. Therefore, even if the arc extinguishing member is disposed proximate to the gap, a large space can be secured between the fixed contact and the arc extinguishing member.
The arc extinguishing member may be configured to move at least in a direction in which the arc extinguishing member separates from the movable contact. In this case, the arc extinguishing member can move toward the direction in which the arc extinguishing member separates from the movable contact due to the pressure increase caused by the arc extinguishing gas. Therefore, even if the arc extinguishing member is disposed proximate to the gap, a large space can be secured between the movable contact and the arc extinguishing member.
The arc extinguishing member may have a shape that tapers toward the gap. In this case, even if the arc extinguishing member is disposed proximate to the gap, a large space can be secured between the contacts and the arc extinguishing member. Thus, the arc extinguishing performance can be further improved.
The contact device may further include a support member that supports the arc extinguishing member such that the arc extinguishing member is movable. The support member may have a spring characteristic. In this case, the support member can support the arc extinguishing member such that the arc extinguishing member is movable owing to the spring characteristic of the support member. The support member may be a coil spring. The support member may be a leaf spring.
At least a part of the arc extinguishing member may have a spring characteristic. In this case, the arc extinguishing member can be movably provided owing to the spring characteristic of the arc extinguishing member.
In a direction from the arc extinguishing member toward the gap, a distance between a tip of the arc extinguishing member and the fixed contact may be smaller than a distance from the housing to the tip of the arc extinguishing member. In this case, the tip of the arc extinguishing member can be disposed proximate to the fixed contact. Thus, the arc extinguishing performance can be improved.
In the direction from the arc extinguishing member toward the gap, a distance between the tip of the arc extinguishing member and the movable contact may be smaller than the distance from the housing to the tip of the arc extinguishing member. In this case, the tip of the arc extinguishing member can be disposed proximate to the movable contact. Thus, the arc extinguishing performance can be improved.
Hereinafter, a relay 1a according to an embodiment will be described with reference to the drawings.
The contact device 2 includes a movable mechanism 10, a first fixed terminal 11, a second fixed terminal 12, a movable contact piece 13, a first movable contact 16, and a second movable contact 17. The first fixed terminal 11 and the second fixed terminal 12 are made from a conductive material such as copper, for example. The first fixed terminal 11 is provided with a first fixed contact 14. The second fixed terminal 12 is provided with a second fixed contact 15. The first fixed contact 14 and the second fixed contact 15 are disposed apart from each other in the left-right direction.
The first fixed terminal 11 includes a first contact support portion 21 and a first external terminal portion 22. The first fixed contact 14 is connected to the first contact support portion 21. The first external terminal portion 22 is connected to the first contact support portion 21. The first external terminal portion 22 protrudes outward from the housing 3. The second fixed terminal 12 includes a second contact support portion 23 and a second external terminal portion 24. The second fixed contact 15 is connected to the second contact support portion 23. The second external terminal portion 24 is connected to the second contact support portion 23. The second external terminal portion 24 protrudes outward from the housing 3.
In
The movable contact piece 13 is made from a conductive material such as copper, for example. The movable contact piece 13 extends in the left-right direction. In the present embodiment, the longitudinal direction of the movable contact piece 13 coincides with the left-right direction. The movable contact piece 13 is disposed facing the first fixed terminal 11 and the second fixed terminal 12 in the upper and lower direction.
The movable contact piece 13 is arranged to be movable in a contact direction Z1 and a separation direction Z2. The contact direction Z1 is a direction in which the movable contact piece 13 approaches the first fixed terminal 11 and the second fixed terminal 12 (the upper direction in
The first movable contact 16 and the second movable contact 17 are supported by the movable contact piece 13. The first movable contact 16 and the second movable contact 17 are disposed apart from each other in the left-right direction. The first movable contact 16 faces the first fixed contact 14 in the upper and lower direction. The second movable contact 17 faces the second fixed contact 15 in the upper and lower direction.
The movable mechanism 10 is disposed such as to be movable in the contact direction Z1 and the separation direction Z2 together with the movable contact piece 13. The movable mechanism 10 includes a drive shaft 19, a holder 26, and a contact spring 27. The drive shaft 19 extends in the upper and lower direction. The drive shaft 19 is connected to the movable contact piece 13. The drive shaft 19 extends toward the lower direction from the movable contact piece 13. The drive shaft 19 is connected to the movable contact piece 13 via the holder 26 and the contact spring 27. The holder 26 is attached to the movable contact piece 13 and holds the movable contact piece 13. The contact spring 27 is disposed between the holder 26 and the movable contact piece 13. The contact spring 27 urges the movable contact piece 13 toward the contact direction Z1 in a state where the movable contacts 16 and 17 contact the fixed contacts 14 and 15.
The housing 3 houses the contact device 2 and the drive device 4. The housing 3 includes a first housing 3a and a second housing 3b. The first housing 3a includes a first storage portion S1. The second housing 3b includes a second storage portion S2. The first storage portion S1 and the second storage portion S2 are partitioned by a partition wall 46. The fixed contacts 14 and 15, the movable contact piece 13, and the movable contacts 16 and 17 are disposed in the first storage portion S1. The drive device 4 is disposed in the second storage portion S2.
The first housing 3a includes a top surface 41, a first side surface 42, and a second side surface 43. The top surface 41 faces the movable contact piece 13 in a moving direction of the movable mechanism 10. The top surface 41 is disposed in the upper direction of the movable contact piece 13. The first side surface 42 and the second side surface 43 are disposed spaced apart from each other in the left-right direction. The first side surface 42 and the second side surface 43 face the movable contact piece 13 in a direction that intersects the moving direction of the movable mechanism 10. That is, the first side surface 42 and the second side surface 43 face the movable contact piece 13 in the left-right direction. The first side surface 42 and the second side surface 43 extend in the moving direction of the movable mechanism 10. The movable contact piece 13 is disposed between the first side surface 42 and the second side surface 43 in the left-right direction.
The drive device 4 operates the movable contact piece 13 by electromagnetic force. The drive device 4 moves the movable contact piece 13 in the contact direction Z1 and the separation direction Z2. The drive device 4 is disposed in the lower direction of the housing 3. The drive device 4 includes a spool 30, a movable iron core 31, a coil 32, a fixed iron core 33, a yoke 34, and a return spring 35.
The spool 30 includes a hole 301 that penetrates the spool 30 in the upper and lower direction. The movable iron core 31 is disposed in the hole 301 of the spool 30. The movable iron core 31 is provided separately from the fixed iron core 33. The movable iron core 31 is connected to the drive shaft 19. The movable iron core 31 is configured to move in the contact direction Z1 and the separation direction Z2. The coil 32 is wound around the spool 30. The coil 32 is energized to generate electromagnetic force that moves the movable iron core 31 toward the contact direction Z1.
The fixed iron core 33 is disposed in the hole 301 of the spool 30. The fixed iron core 33 is disposed facing the movable iron core 31. The return spring 35 is disposed between the movable iron core 31 and the fixed iron core 33. The return spring 35 urges the movable iron core 31 toward the separation direction Z2.
The yoke 34 is disposed to surround the coil 32. The yoke 34 is disposed on a magnetic circuit formed by the coil 32. Portions of the yoke 34 are disposed in the upper direction of the coil 32, to the sides of the coil 32, and in the lower direction of the coil 32.
Next, an operation of the relay 1a will be described. When the coil 32 is not energized, the drive device 4 is not magnetized. In this case, the drive shaft 19 is pressed toward the separation direction Z2 together with the movable iron core 31 by elastic force of the return spring 35. Therefore, the movable contact piece 13 is also pressed toward the separation direction Z2, and the movable contacts 16 and 17 are in their open positions illustrated in
When the coil 32 is energized, the drive device 4 is magnetized. In this case, electromagnetic force of the coil 32 causes the movable iron core 31 to move toward the contact direction Z1 against the elastic force of the return spring 35. As a result, both the drive shaft 19 and the movable contact piece 13 move toward the contact direction Z1, and the movable contacts 16 and 17 move to their closed positions illustrated in
When a current to the coil 32 is stopped and the coil is demagnetized, the movable iron core 31 is pressed toward the separation direction Z2 by the elastic force of the return spring 35. As a result, both the drive shaft 19 and the movable contact piece 13 move toward the separation direction Z2, and the movable contacts 16 and 17 return to the open positions illustrated in
As illustrated in
The first and second arc extinguishing members 51 and 52 may be formed of a material such as a phenol resin, a hydrogen storage metal, or a titanium hydride. Alternatively, the first and second arc extinguishing members 51 and 52 may be formed of, for example, a thermosetting resin such as an unsaturated polyester resin or a melamine resin. Alternatively, the first and second arc extinguishing members 51 and 52 may be formed of a thermoplastic resin such as a polyolefin resin, a polyamide resin, or a polyacetal resin. Alternatively, the first and second arc extinguishing members 51 and 52 may be formed of another material.
The first arc extinguishing member 51 is disposed facing a gap G1 (hereinafter referred to as a “first gap G1”) between the first fixed contact 14 and the first movable contact 16 when the movable contacts 16 and 17 are in the open positions. The first arc extinguishing member 51 has a shape that tapers toward the first gap G1. The second arc extinguishing member 52 faces a gap G2 (hereinafter referred to as a “second gap G2”) between the second fixed contact 15 and the second movable contact 17 when the movable contacts 16 and 17 are in the open positions. The second arc extinguishing member 52 has a shape that tapers toward the second gap G2.
The first arc extinguishing members 51 is connected to the first side surface 42 via the first support member 71. The second arc extinguishing member 52 is connected to the second side surface 43 via the second support member 72. The first arc extinguishing member 51 protrudes from the first side surface 42 toward the first gap G1. The second arc extinguishing member 52 protrudes from the second side surface 43 toward the second gap G2.
The first support member 71 supports the first arc extinguishing member 51 such that the first arc extinguishing member 51 is movable. The first support member 71 is connected to the first housing 3a and the first arc extinguishing member 51. Specifically, the first support member 71 is connected to the first side surface 42 and the first arc extinguishing members 51. The second support member 72 supports the second arc extinguishing member 52 such that the second arc extinguishing member 52 is movable. The second support member 72 is connected to the first housing 3a and the second arc extinguishing members 52. Specifically, the second support member 72 is connected to the second side surface 43 and the second arc extinguishing members 52. The first support member 71 is a coil spring and has a spring characteristic. The second support member 72 is a coil spring and has a spring characteristic.
The first support member 71 supports the first arc extinguishing member 51 such that a tip of the first arc extinguishing member 51 moves to separate from the first fixed contact 14 at least in the upper and lower direction. The first support member 71 supports the first arc extinguishing member 51 such that the tip of the first arc extinguishing member 51 move to separate from the first movable contact 16 at least in the upper and lower direction. The second support member 72 supports the second arc extinguishing member 52 such that a tip of the second arc extinguishing member 52 move to separate from the second fixed contact 15 at least in the upper and lower direction. The second support member 72 supports the second arc extinguishing member 52 such that the tip of the second arc extinguishing member 52 move to separate from the second movable contact 17 at least in the upper and lower direction.
Specifically, the first support member 71 supports the first arc extinguishing member 51 such that the tip of the first arc extinguishing member 51 is movable in the upper and lower direction. The first support member 71 supports the first arc extinguishing member 51 such that the tip of the first arc extinguishing member 51 is movable in the left-right direction. The first support member 71 supports the first arc extinguishing member 51 such that the tip of the first arc extinguishing member 51 is movable in the front-back direction.
The second support member 72 supports the second arc extinguishing member 52 such that the tip of the second arc extinguishing member 52 is movable in the upper and lower direction. The second support member 72 supports the second arc extinguishing member 52 such that the tip of the second arc extinguishing member 52 is movable in the left-right direction. The second support member 72 supports the second arc extinguishing member 52 such that the tip of the second arc extinguishing member 52 is movable in the front-back direction. However, a movable direction of the first arc extinguishing member 51 and the second arc extinguishing member 52 is not limited to the above-described direction and may be changed.
The base portion 62 has a larger outer shape than the tip portion 61.
Specifically, the base portion 62 has a larger area than the tip portion 61 when viewed from a direction in which the first arc extinguishing member 51 faces the first gap G1. In other words, the tip portion 61 has a smaller area than the base portion 62 when viewed from the direction in which the first arc extinguishing member 51 faces the first gap G1. The dimension of the base portion 62 in the upper and lower direction is larger than the dimension of the tip portion 61 in the upper and lower direction. In other words, the dimension of the tip portion 61 in the upper and lower direction is smaller than the dimension of the base portion 62 in the upper and lower direction.
The first arc extinguishing member 51 is disposed proximate to the first gap G1. Specifically, in a direction from the first arc extinguishing member 51 toward the first gap G1, a distance D1 between a tip of the first arc extinguishing member 51 and the first fixed contact 14 is smaller than a distance D2 from the first housing 3a (the first side surface 42) to the tip of the first arc extinguishing member 51. In the direction from the first arc extinguishing member 51 toward the first gap G1, a distance D3 between the tip of the first arc extinguishing member 51 and the first movable contact 16 is smaller than the distance D2 from the first housing 3a (the first side surface 42) to the tip of the first arc extinguishing member 51.
The tapered portion 63 includes a first tapered surface 64 and a second tapered surface 65. The first tapered surface 64 and the second tapered surface 65 are inclined such that a distance between the first tapered surface 64 and the second tapered surface 65 decreases toward the first gap G1. The first tapered surface 64 faces the first fixed contact 14. The second tapered surface 65 faces of the first movable contact 16. At least a part of the tip portion 61 is positioned between a lower end of the first fixed contact 14 and an upper end of the first movable contact 16.
The second arc extinguishing member 52 has a same structure as that of the first arc extinguishing member 51 except that the second arc extinguishing member 52 is provided substantially left-right symmetrically with respect to the first arc extinguishing member 51. Therefore, detailed description of the second arc extinguishing member 52 is omitted.
In the contact device 2 according to the present embodiment described above, the first arc extinguishing member 51 is movably supported by the first support member 71. Therefore, when the arc extinguishing gas is generated, the arc extinguishing gas causes an increase in pressure, whereby the first arc extinguishing member 51 moves. Thus, even if the first arc extinguishing member 51 is disposed proximate to the first gap G1, a large space can be secured between the first fixed contact 14 and the first arc extinguishing member 51. Alternatively, a large space can be secured between the first movable contact 16 and the first arc extinguishing member 51. Accordingly, an arc extinguishing gas can be generated proximate to the first gap G1 and an arc can easily pass through a space between the first fixed contact 14 and the first arc extinguishing member 51 or a space between the first movable contact 16 and the first arc extinguishing member 51. As a result, the arc is easily extended and quickly extinguished. Therefore, the arc extinguishing performance can be improved.
When the arc extinguishing gas is generated, pressure is instantly increased. This causes the first support member 71 to deform elastically, whereby the first arc extinguishing member 51 moves. However, after the instant pressure increase is finished, the elastic deformation of the first support member 71 is released and the first arc extinguishing member 51 returns to an original position.
The first arc extinguishing member 51 has a shape that tapers toward the first gap G1. Therefore, even if the arc extinguishing member 51 is disposed proximate to the first gap G1, a large space can be secured between the first fixed contact 14 and the first arc extinguishing member 51. Alternatively, a large space can be secured between the first movable contact 16 and the first arc extinguishing member 51. Thus, the arc extinguishing performance owing to the arc extinguishing gas can be further improved. The second arc extinguishing member 52 and the second support member 72 achieve the same effect as that of the first arc extinguishing member 51 and the first support member 71 as described above.
Although an embodiment of the present invention has been described so far, the present invention is not limited to the above embodiment and various modifications may be made within the scope of the invention. For example, the contact device may be used for a breaker, a switch, or the like, instead of a relay.
In the above embodiment, the drive device 4 pushes out the drive shaft 19 from the drive device 4 side so that the movable contact piece 13 moves toward the contact direction Z1. Also, the drive device 4 pulls in the drive shaft 19 toward the drive device 4 side so that the movable contact piece 13 moves toward the separation direction Z2. However, the operation direction of the drive shaft 19 for opening and closing the contacts may be opposite to that in the above embodiment. That is, the drive device 4 may pull in the drive shaft 19 toward the drive device 4 side so that the movable contact piece 13 moves toward the contact direction Z1. The drive device 4 may push out the drive shaft 19 from the drive device 4 side so that the movable contact piece 13 moves toward the separation direction Z2. That is, the contact direction Z1 and the separation direction Z2 may be opposite to those in the above embodiment.
The relay 1a described above is a so-called plunger relay, but the present invention may be applied to another type of relay, instead of the plunger relay. For example, as illustrated in
When the coil 32 is demagnetized, the armature 36 swings toward the opposite direction by elastic force of a hinge spring 38. As a result, the card 37, the movable contact piece 13, and the movable contact 16 move toward the separation direction Z2, and the movable contact 16 separates from the fixed contact 14. The arc extinguishing member 51 is disposed facing the gap G1 between the movable contact 16 and the fixed contact 14. The arc extinguishing member 51 has a shape that tapers toward the gap G1. The arc extinguishing member 51 is supported by the support portion 71 such that the arc extinguishing member 51 is movable. Accordingly, the hinged relay 1b also achieves the same effect as that of the relay 1a according to the above-described embodiment.
The shape or disposition of the first fixed terminal 11, the second fixed terminal 12, or the movable contact piece 13 may be changed. The shape or disposition of the coil 32, the spool 30, or the yoke 34 may be changed. The shape or disposition of the first fixed contact 14, the second fixed contact 15, the first movable contact 16, and the second movable contact 17 may be changed.
The first fixed contact 14 may be provided separately from or integrated with the first fixed terminal 11. The second fixed contact 15 may be provided separately from or integrated with the second fixed terminal 12. The first movable contact 16 may be provided separately from or integrated with the movable contact piece 13. The second movable contact 17 may be provided separately from or integrated with the movable contact piece 13.
The shape and/or disposition of the arc extinguishing member is not limited to that of the above-described embodiment and may be changed. For example, the arc extinguishing member may be connected to the top surface 41 via the support member, instead of the side surfaces 42 and 43 of the housing 3. Alternatively, the arc extinguishing member may be connected to the partition wall 46 via the support member.
In the above-described embodiment, the first arc extinguishing member 51 faces the first gap G1 in the left-right direction. The second arc extinguishing member 52 faces the second gap G2 in the left-right direction. However, the direction in which the arc extinguishing member and the gap face each other is not limited to the left-right direction, that is, not limited to the longitudinal direction of the movable contact piece 13. For example,
In the above-described embodiment, the first arc extinguishing member 51 and the second arc extinguishing member 52 are provided. However, the number of arc extinguishing members is not limited to two and may be less than two or more than two. For example, one of the first arc extinguishing member 51 or the second arc extinguishing member 52 may be omitted. Alternatively,
The arc extinguishing member may have another shape, instead of a trapezoidal shape. For example, the arc extinguishing member may have a pyramid shape, a truncated pyramid shape, a cone shape, or a truncated cone shape. Alternatively, as illustrated in
The support member may have another shape, instead of a coil spring. For example, as illustrated in
The first arc extinguishing member 51 may be movably provided without using the support member. For example, as illustrated in
Number | Date | Country | Kind |
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2018-215493 | Nov 2018 | JP | national |
This application is the U.S. National Phase of International Application No. PCT/JP2019/040570, filed on Oct. 16, 2019. This application claims priority to Japanese Patent Application No. 2018-215493, filed Nov. 16, 2018. The contents of those applications are incorporated by reference herein in their entireties.
Filing Document | Filing Date | Country | Kind |
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PCT/JP2019/040570 | 10/16/2019 | WO | 00 |