Sealed relay

Abstract

In case of using multi-contacts or flat braided wires for constituting a current carrying structure of a movable part in a vacuum relay, problems tend to appear, which are enlargement of a control mechanism, complication, increased operation force and the like. The vacuum relay 1 includes an insulating cylinder 2, a first relay connecting portion 4 that is connected to one open end of the insulating cylinder 2 and has on its inner surface a first contact 3, a second relay connecting portion 5 that is arranged in the insulating cylinder 2 to face the first relay connecting portion 4, a movable member 7 that is movably arranged between the first and second relay connecting portions 4 and 5 and has a second contact that is brought into contact with the first contact when the movable member is moved toward the first relay connecting portion, and a control mechanism 8 that moves the movable member 7 in both directions to establish and break the contact between the two contacts. Between the movable member 7 and the second relay connecting portion 5, there is provided a bellows 11 through which the movable member 7 and the second relay connecting portion 5 are electrically connected.

Claims

1. A sealed relay comprising: an insulating cylinder; a first relay connecting portion connected to a first open end of the insulating cylinder to hermetically close the first open end, the first relay connecting portion having a first contact on an inner surface of the first relay connecting portion; a second relay connecting portion connected to the insulating cylinder in a manner to face the first relay connecting portion leaving a given distance therebetween, the second relay connecting portion extending through the insulating cylinder; a movable member movably arranged between the first relay connecting portion and the second relay connecting portion, the movable member having a second contact configured to contact the first contact when the movable member is moved toward the first relay connecting portion; a control mechanism configured to move the movable member in a first direction to establish the contact between the first contact and the second contact and a second direction to break the contact between the first contact and the second contact; and a bellows provided between the movable member and the second relay connecting portion to electrically connect the movable member and the second relay connecting portion, such that the first relay connecting portion and the second relay connecting portion are configured to become electrically connected through the movable member when the first contact and the second contact are in contact, wherein the bellows is of a double structure type including an inner bellows and an outer bellows, the inner bellows having a hermetically sealing function to prevent outside air from entering into a space that is defined by at least the first relay connecting portion, the insulating cylinder and the inner bellows, the outer bellows having a current carrying function to electrically connect the movable member to the second relay connecting portion, the movable member comprises a circular flange portion that carries thereon the second contact and a shaft portion extending from the circular flange portion toward the control mechanism, the shaft portion configured to be axially moved by the control mechanism, and each of the inner bellows and the outer bellows has a first end directly connected to the shaft portion of the movable member and a second end connected to the second relay connecting portion.

2. The sealed relay as claimed in claim 1, wherein the inner bellows is arranged to keep an interior of the insulating cylinder in a vacuum condition.

3. The sealed relay as claimed in claim 1, wherein the control mechanism is placed at a position opposite to the movable member with respect to the second relay connecting portion.

4. The sealed relay as claimed in claim 1, wherein contact between the first contact and second contact turns on the sealed relay, and non-contact between the first contact and second contact turns off the sealed relay.

5. The sealed relay as claimed in claim 1, wherein the control mechanism comprises an air cylinder.

6. The sealed relay as claimed in claim 1, wherein the control mechanism comprises an air cylinder configured to drive the shaft portion.

7. The sealed relay as claimed in claim 1, wherein the shaft portion has a diameter smaller than a diameter of the circular flange portion.

8. The sealed relay as claimed in claim 7, wherein the second contact is provided at a center of an upper surface of the circular flange portion of the movable member, and the shaft portion is provided at a center of a lower surface of the circular flange portion of the movable member.

9. The sealed relay as claimed in claim 7, wherein the circular flange portion of the movable member is disposed above the second relay connecting portion, and the shaft portion of the movable member is received within a receiving hole formed in the second relay connecting portion.

10. The sealed relay as claimed in claim 1, wherein the first relay connecting portion comprises a circular plate.

11. The sealed relay as claimed in claim 1, wherein the insulating cylinder is divided into a first insulated cylinder member and a second insulated cylinder member by the second relay connecting portion.

12. The sealed relay as claimed in claim 11, wherein the second relay connecting portion is sandwiched between the first insulated cylinder member and the second insulated cylinder member.

13. The sealed relay as claimed in claim 1, wherein the second relay connecting portion is connected to a second open end of the insulating cylinder.

14. The sealed relay as claimed in claim 1, wherein the circular flange portion of the movable member is comprised of copper alloy, and the shaft portion of the movable member is comprised of stainless steel.

15. The sealed relay as claimed in claim 1, further comprising: a housing portion configured to house the control mechanism; and a connecting member configured to connect the housing portion to the insulating cylinder.

16. The sealed relay as claimed in claim 1, wherein the circular flange portion of the movable member is comprised of a first material that is conductive, and the shaft portion of the movable member is comprised of a second material that is different from the first material.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) FIG. 1 is a sectional view of a sealed relay of the present invention, in which a left-half part from a center line CL shows a contact condition wherein first and second contacts are in contact with each other and a right-half part from the center line shows a non-contact condition wherein the first and second contacts are not in contact with each other.

(2) FIG. 2 is a sectional view of a sealed relay of the present invention, in which a movable member includes a flange portion and a shaft portion, the flange portion is constructed small in size as compared to FIG. 1, and a bellows is directly connected to the shaft portion. A left-half part from a center line CL shows a contact condition wherein first and second contacts are in contact with each other and a right-half part from the center line shows a non-contact condition wherein the first and second contacts are not in contact with each other.

EMBODIMENT OF INVENTION

(3) In the following, an embodiment of the present invention will be described with reference to FIG. 1.

(4) In FIG. 1, denoted by numeral 1 is a vacuum relay that is an example of sealed relays. The vacuum relay 1 comprises an insulating cylinder 2, a first relay connecting portion 4 that is connected to one open end of the insulating cylinder 2 and equipped at its inner surface with a first contact (electrode) 3, a second relay connecting portion 5 that is arranged in the insulating cylinder 2 in a manner to face against the first relay connecting portion 4 while leaving a given distance therebetween, a movable member 7 that is movably arranged between the first relay connecting portion 4 and the second relay connecting portion 5 and has a second contact 6 that is brought into contact with the first contact 3 when the movable member 7 is moved toward the first relay connecting portion 4 and a control mechanism 8 that moves the movable member 7 in both a direction to establish the contact between the first and second contacts 3 and 6 and the other direction to break the contact between the first and second contacts 3 and 6 selectively.

(5) Between the movable member 7 and the second relay connecting portion 5, there is disposed a retractable bellows 11.

(6) The bellows 11 is of a double structure type including an inner bellows 11a and an outer bellows 11b, and the inner bellows 11a functions to keep the interior of the insulating cylinder 2 in a vacuum condition and the outer bellows 11b functions to electrically connect the movable member 7 and the second relay connecting portion 5. (In the following, the inner bellows 11a will be referred to as a hermetic sealing bellows and the outer bellows 11b will be referred to as a current carrying bellows). If desired, the bellows 11 may be of a single structure, not the double structure, which functions to effect both the hermetic sealing and the current carrying.

(7) In the following, the insulating cylinder 2, first relay connecting portion 4, second relay connecting portion 5, control mechanism 8 and bellows 11 will be described in detail.

(8) The insulating cylinder 2 is divided into first and second cylinder members 2a and 2b, and these cylinder members are made of ceramics.

(9) The first relay connecting portion 4 is shaped into a circular plate and hermetically connected to an upper open end of the first cylinder member 2a. At a center portion of a lower surface of the first relay connecting portion 4, there is provided the first contact 3.

(10) The second relay connecting portion 5 is tightly sandwiched between the first cylinder member 2a and the second cylinder member 2b. At a center part (viz., a portion that corresponds to a center part of the insulating cylinder 2) of the second relay connecting portion 5, there is formed a shaft portion receiving hole 5a for receiving therein a shaft portion 7b of a next-mentioned movable member 7.

(11) The movable member 7 comprises a circular flange portion 7a that has at a center part of an upper surface thereof the second contact 6 and a shaft portion 7b that is provided at a center of a lower surface of the circular flange portion 7a and has a diameter smaller than that of the circular flange portion 7a. The flange portion 7a is made of a high conductive material such as copper alloy or the like.

(12) The shaft portion 7b is projected toward a lower area of the second relay connecting portion 5 through the shaft portion receiving hole 5a formed in the second relay connecting portion 5. A lower end of the shaft portion 7b is connected to the control mechanism 8 through an insulating rod 12. The shaft portion 7b is made of stainless steel or the like.

(13) The control mechanism 8 uses an air cylinder. The control mechanism 8 is installed in a control mechanism housing portion 13. An upper end of the control mechanism housing portion 13 is connected to the second cylinder member 2b through a connecting member 14.

(14) In the following, the bellows 11 will be described. As is mentioned hereinabove, the bellows 11 is of a double construction type including the hermetically sealing inner bellows 11a and the current carrying outer bellows 11b.

(15) The hermetically sealing bellows 11a is arranged at an outer circumferential side of the shaft portion 7b of the movable member 7 while surrounding the shaft portion 7b. The hermetically sealing bellows 11a has one end connected to the second relay connecting portion 5 and the other end connected to the flange portion 7a of the movable member 7.

(16) The hermetically sealing bellows 11a has a hermetically sealing performance that prevents outside air from entering the interior of the first cylinder member 2a through the shaft portion receiving hole 5a. The hermetically sealing bellows 11a is made of a hermetically sealing material.

(17) The current carrying bellows 11b is arranged around the hermetically sealing bellows 11a. Like the hermetically sealing bellows 11a, the current carrying bellows 11b has one end connected to the second relay connecting portion 5 and the other end connected to the flange portion 7a.

(18) The current carrying bellows 11b electrically connects the movable member 7 and the second relay connecting portion 5. The current carrying bellows 11b is made of electrically conductive material.

(19) In the embodiment shown in FIG. 1, the insulating cylinder 2 is divided into the first and second cylinder members 2a and 2b, and the second relay connecting portion 5 is tightly sandwiched between these two cylinder members 2a and 2b. However, if desired, a modification may be employed in which the insulating member 2 is constructed by only the first cylinder member 2a without usage of the second cylinder member 2b and the first relay connecting portion 4 is arranged at one open end of the first cylinder member 2a and the second relay connecting portion 5 is arranged at the other open end of the member 2a. In this modification, the control mechanism housing portion 13 or the connecting member 14 is made of insulating material.

(20) In the following, operation and effects of the above-mentioned vacuum relay 1 will be described. As is shown by a left-half part of FIG. 1, when the first and second contacts 3 and 6 are brought into contact with each other, an electrically connected condition is established in which the first relay connecting portion 4 and the second relay connecting portion 5 are electrically connected to each other through the movable member 7 and the current carrying bellows 11b.

(21) When the movable member 7 is pulled down toward the control mechanism 8 from its position indicated in the left-half part of FIG. 1, the first contact 3 and the second contact 6 are separated from each other as is indicated in the right-half part of FIG. 1, so that the electric connection between the first relay connecting portion 4 and the second relay connecting portion 5 is blocked.

(22) Furthermore, when the movable member 7 is moved toward the first contact 3 by the control mechanism 8, the first contact 3 and the second contact 6 are brought into contact with each other as is indicated by the left-half part of FIG. 1, so that the first relay connecting portion 4 and the second relay connecting portion 5 take an electrically connected condition.

(23) In the above-mentioned embodiment, the current carrying is made by the current carrying outer bellows 11b, and thus, the current carrying outer bellows 11b is preferably made of high conductive material such as copper alloy or the like. While the hermetically sealing bellows 11a and the shaft portion 7b of the movable member 7 may be made of low conductive material such as stainless steel or the like. Furthermore, in case wherein the flange portion 7a of the movable member 7 is constructed small in size and the bellows is directly connected to the shaft portion 7b (see vacuum relay 1 of FIG. 2), it is preferable to use a high conductive material for producing the shaft portion 7b. Furthermore, as is mentioned hereinabove, an arrangement may be employed in which the second relay connecting portion 5 is arranged at the other open end of the insulating cylinder 2 and the control mechanism housing portion 13 and the connecting member 14 are made of insulating material.

EXPLANATION OF REFERENCE NUMERALS

(24) 1 . . . sealed relay 2 . . . insulating cylinder 3 . . . first contact 4 . . . first relay connecting portion 5 . . . second relay connecting portion 6 . . . second contact 7 . . . movable member 7a . . . flange portion 7b . . . shaft portion 8 . . . control mechanism 11 . . . bellows 11a . . . inner bellows (hermetically sealing bellows) 11b . . . outer bellows (current carrying bellows)