TEMPERATURE-DEPENDENT SWITCH

Abstract

A temperature-dependent switch having a temperature-dependent switching mechanism and a housing on which first and second stationary contacts are arranged. The temperature-dependent switching mechanism is configured to switch in a temperature-dependent manner between a closed state, in which the switching mechanism establishes an electrically conductive connection between the first and second stationary contacts, and an open state, in which the switching mechanism disconnects the electrically conductive connection. The switching mechanism comprises a carrier body, a spring element, a bimetallic element and a current transfer member. The current transfer member is connected to the bimetallic element by a connecting element other than the carrier body. In the closed state, the current transfer member is pressed against the first and second stationary contacts in order to establish the electrically conductive connection, and in the open state it is lifted off the first and second stationary contacts in order to disconnect the electrically conductive connection.

Claims

1. A temperature-dependent switch, comprising: a temperature-dependent switching mechanism and a housing in which the temperature-dependent switching mechanism is arranged, wherein the housing comprises a first stationary contact and a second stationary contact, wherein the temperature-dependent switching mechanism is configured to switch in a temperature-dependent manner between a closed state, in which the switching mechanism establishes an electrically conductive connection between the first stationary contact and the second stationary contact, and an open state, in which the switching mechanism disconnects the electrically conductive connection, wherein the switching mechanism comprises a carrier body movable in the housing, a spring element supporting the carrier body, a bimetallic element arranged in the carrier body and a current transfer member that is connected to the bimetallic element by a connecting element other than the carrier body, wherein, in the closed state, the current transfer member is pressed against the first stationary contact and the second stationary contact in order to establish the electrically conductive connection, and wherein, in the open state, the current transfer member is lifted off the first stationary contact and the second stationary contact in order to disconnect the electrically conductive connection.

2. The temperature-dependent switch according to claim 1, wherein, in the closed state and in the open state, the spring element exerts on the carrier body a first force acting in a first direction, wherein, in the closed state, the bimetallic element exerts on the current transfer member a second force acting in the first direction in order to press the current transfer member against the first stationary contact and the second stationary contact, and wherein, in the open state, the bimetallic element exerts on the current transfer member a third force acting in a second direction opposite to the first direction in order to lift the current transfer member off the first stationary contact and the second stationary contact.

3. The temperature-dependent switch according to claim 1, wherein the carrier body is ring-shaped or pot-shaped.

4. The temperature-dependent switch according to claim 1, wherein the carrier body comprises an electrically insulating material.

5. The temperature-dependent switch according to claim 1, wherein the carrier body at least partially surrounds a circumferential edge of the bimetallic element.

6. The temperature-dependent switch according to claim 1, wherein the carrier body at least partially surrounds a circumferential edge of the current transfer member without contacting it.

7. The temperature-dependent switch according to claim 1, wherein the current transfer member moves relative to the carrier body when the temperature-dependent switching mechanism switches between the closed state and the open state.

8. The temperature-dependent switch according to claim 1, wherein, in the open state, the spring element presses the carrier body against an inner side of the housing.

9. The temperature-dependent switch according to claim 8, wherein, in the closed state, the carrier body is spaced apart from the inner side of the housing.

10. The temperature-dependent switch according to claim 1, wherein, in the closed state, a circumferential edge of the bimetallic element is supported against a first section of the carrier body in order to press the current transfer member against the first stationary contact and the second stationary contact, and wherein, in the open state, the circumferential edge of the bimetallic element is supported against a second section of the carrier body, which is spaced apart from the first section, in order to lift the current transfer member off the first stationary contact and the second stationary contact.

11. The temperature-dependent switch according to claim 10, wherein the first section and the second section are arranged opposite to each other and on opposite sides of the bimetallic element.

12. The temperature-dependent switch according to claim 10, wherein the carrier body comprises a first carrier part body and a second carrier part body loosely arranged on the first carrier part body, wherein the first section is arranged on the first carrier part body and the second section is arranged on the second carrier part body.

13. The temperature-dependent switch according to claim 1, wherein the connecting element comprises a rivet.

14. The temperature-dependent switch according to claim 1, wherein the housing comprises a lower part and an upper part held on the lower part, wherein the first stationary contact and the second stationary contact are arranged on the upper part, and wherein the spring element is clamped between the lower part and the carrier body.

15. The temperature-dependent switch according to claim 14, wherein the lower part and the upper part comprises an electrically insulating material.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0062] FIG. 1 a schematic sectional view of a first embodiment of the switch, wherein the temperature-dependent switching mechanism of the switch is in its closed state;

[0063] FIG. 2 a schematic sectional view of the embodiment of the switch shown in FIG. 1, wherein the temperature-dependent switching mechanism of the switch is in its open state;

[0064] FIG. 3 a schematic sectional view of a second embodiment of the switch, wherein the temperature-dependent switching mechanism of the switch is in its closed state;

[0065] FIG. 4 a schematic sectional view of the embodiment of the switch shown in FIG. 3, wherein the temperature-dependent switching mechanism of the switch is in its open state;

[0066] FIG. 5 a schematic sectional view of a switch according to the prior art, wherein the temperature-dependent switching mechanism of the switch is in its closed state; and

[0067] FIG. 6 a schematic sectional view of the switch shown in FIG. 5, wherein the temperature-dependent switching mechanism of the switch is in its open state.

DESCRIPTION OF PREFERRED EMBODIMENTS

[0068] FIGS. 1-4 show two embodiments of the temperature-dependent switch, wherein FIGS. 1 and 3 each show the closed state of the switch and FIGS. 2 and 4 each show the open state of the switch. In each case, the switch is marked in its entirety with the reference number 10.

[0069] The switch 10 comprises a housing 12 in which a temperature-dependent switching mechanism 14 is arranged.

[0070] The housing 12 comprises a substantially pot-shaped lower part 16, into which the switching mechanism 14 is inserted. The lower part 16 is closed by an upper part 18, which is held at the lower part 16 by the raised edge 20 of the latter.

[0071] While the lower part 16 can be made of any material, the upper part 18 is made of insulating material. Preferably, the upper part 18 is made of ceramic in order to comprise the greatest possible heat resistance and to have a lower risk of outgassing compared to plastic.

[0072] Two rivets 22, 24 are arranged in the upper part 18, the inner heads of which serve as stationary contacts 26, 28 for the switching mechanism 14. The rivets 22, 24 function as piercing contacts which penetrate the upper part 18 and to the top sides of which the electrical external terminals 30, 32 can be connected. For example, the external terminals 30, 32 are soldered in the form of stranded wires, connection plates or other electrical connection lines to the sections of the rivets 22, 24 that protrude upwardly from the upper part 18.

[0073] The two stationary contacts 26, 28 are assigned a current transfer member 34, which is configured as a circular disc-shaped contact bridge. The current transfer member 34 is coupled with a bimetallic element 38, which is also in the form of a circular disc, by means of a connecting element 36. The connecting element 36 is designed as a rivet, which is passed through a hole provided centrally in the current transfer member 34 and is preferably firmly connected to the current transfer member 34.

[0074] The bimetallic element 38 is held on the rivet 36 in a captive manner, but with play. The rivet 36 is passed through a hole provided centrally in the bimetallic element 38, wherein the bimetallic element 38 is held captive but with play with its inner edge 40 between the current transfer member 34 and a support shoulder 42 of enlarged diameter formed on the bottom side of the rivet 36.

[0075] In addition to the current transfer member 34, the connecting element 36 and the bimetallic element 38, the switching mechanism 14 further comprises a carrier body 44 and a spring element 46 supporting the carrier body 44. The carrier body 44 serves in particular as a support for the part of the switching mechanism 14 comprising the current transfer member 34, the connecting element 36 and the bimetallic element 38. The carrier body 44 can either be detachably mounted on the spring element 46 or fixed to the spring element 46 in a material-locking manner.

[0076] The carrier body 44 is designed as a substantially ring-shaped body of revolution which surrounds the circumferential, outer edge 48 of the bimetallic element 38. The circumferential side 50 of the carrier body 44 can rest against the inner circumferential side 52 and be guided on the latter in a sliding manner. Depending on the embodiment, however, it is also possible that the circumferential side 50 of the carrier body 44 is arranged at a distance from the inner circumferential side 52, so that the carrier body 44 then accordingly has no contact with the lower part 16 of the housing 12.

[0077] Unlike the bimetallic element 38, the current transfer member 34 has no direct contact with the carrier body 44. The circumferential edge 54 of the current transfer member 34 is spaced from the inner wall of the carrier body 44. Accordingly, the current transfer member 34 is movable relative to the carrier body 44 without collision.

[0078] The carrier body 44 is movably stored within the housing 12. In the closed state of the switching mechanism 14 shown in FIG. 1, the spring element 46 presses upwardly in the direction of an inner side 56 of the upper part 18 of the housing 12. As can be seen from FIG. 1, however, the carrier body 44 is spaced apart from this inner side 56 of the upper part 18 of the housing in the closed state of the switching mechanism 14. At the same time, the bimetallic element 38 is supported with its circumferential edge 48 against the carrier body 44 and presses, with its inner edge 40, the current transfer member 34 upwardly against the two stationary contacts 26, 28. More precisely, the bimetallic element 38 is supported with its circumferential edge 48 against a first section 60 of the carrier body 44.

[0079] In the closed state of the switching mechanism 14, the spring element 46 and the bimetallic element 38 thus jointly exert the contact pressure with which the current transfer member 34 is pressed against the two stationary contacts 26, 28. The spring element 46 and the bimetallic element 38 are connected mechanically in series in the closed state shown in FIG. 1. The force exerted by the spring element 46 on the carrier body 44 acts in the same direction 58 (upwardly) as the force exerted by the bimetallic element 38 on the current transfer member 34. This direction, indicated with an arrow 58, is referred to as the first direction in the present case.

[0080] If, starting from the situation shown in FIG. 1, in which the switching mechanism 14 is in its closed state and establishes the electrically conductive connection between the two contacts 26, 28 via the current transfer member 34, the temperature of the bimetallic element 38 rises above the response temperature, the bimetallic element 38 snaps from its convex high-temperature configuration shown in FIG. 1 to its concave low-temperature configuration shown in FIG. 2. Thereby, the bimetallic element 38 presses the connecting element 36 configured as a rivet and the current transfer member 34 firmly connected thereto downwards in the direction of the arrow 62, thereby lifting the current transfer member 34 off the contacts 26, 28 and interrupting the electrically conductive connection between the two contacts 26, 28.

[0081] The bimetallic element 38 thereby exerts a force on the connecting element 36 and the current transfer member 34, which force acts in a second direction 62 opposite to the first direction 58. With its circumferential outer edge 48, the bimetallic element 38 is supported for this purpose on a second section 64 of the carrier body 44. This second section 64 is arranged on an opposite side of the bimetallic element 38 compared to the first section 60. In the embodiment shown in FIGS. 1 and 2, the second section 64 is configured by a bead or a radially inwardly projecting, circumferential nose, which causes a cross-sectional narrowing of the inner diameter of the carrier body 44 and serves as a counter-holder for the bimetallic element 38 in the open state of the switching mechanism 14.

[0082] In the open state of the switching mechanism 14 shown in FIG. 2, the bimetallic element 38 exerts a force on the connecting element 36 and thus also indirectly on the current transfer member 34 in the second direction 62, while the spring element 46 continues to exert a force on the carrier body 44 which acts in the opposite first direction 58. As a result, although the current transfer member 34 is pulled downwardly by the contacts 26, 28 due to the high temperature configuration of the bimetallic element 38, the carrier body 44 is pushed upwardly until it rests with its top side against the inside or bottom side 56 of the upper housing part 18. Thus, in the open state of the switching mechanism 14 shown in FIG. 2, the carrier body 44 is clamped between the spring element 46 and the upper part 18 of the housing 12. The force exerted by the spring element 46 on the carrier body 44 thus does not reduce the force exerted by the bimetallic element 38 on the connecting element 36.

[0083] The carrier body 44 thus moves upwardly along the first direction 58 during the switching process, in which the switching mechanism 14 is moved from the closed state shown in FIG. 1 to the open state shown in FIG. 2 due to the temperature, while the current transfer member 34 simultaneously moves downwardly in the opposite direction 62. Switching from the closed state to the open state thus leads to a partial relief or expansion of the spring element 46.

[0084] FIGS. 3 and 4 show a second embodiment of the switch 10, which differs essentially by the embodiment of the carrier body 44. The other devices of the switch housing 12 and the switching mechanism 14 do not differ from the first embodiment shown in FIGS. 1 and 2 and are therefore not explained again.

[0085] FIG. 3 shows the closed state of switch 10. FIG. 4 shows the open state of switch 10.

[0086] In the second embodiment of the switch 10 shown in FIGS. 3 and 4, the carrier body 44 is composed of two parts. The carrier body 44 comprises a first carrier part body 66 and a second carrier part body 68. Both carrier part bodies 66, 68 are loosely connected to each other.

[0087] Both carrier part bodies 66, 68 are designed as ring-shaped bodies. The second carrier part body 68 is placed on or attached to the first carrier part body 66. The first carrier part body 66 is essentially L-shaped in cross-section. The cross-section of the second carrier part body 68 is essentially inverted L-shaped.

[0088] In the closed state shown in FIG. 3, the bimetallic element 38 is supported with its circumferential outer edge 48 on the first section 60 provided on the first support member 66. The second section 64 of the carrier body 44, on which the circumferential edge 48 of the bimetallic element 38 is supported in the closed state shown in FIG. 4, is arranged on the second carrier body 68 according to the second embodiment. Thus, the bimetallic element 38 is supported on the first carrier part body 66 in the closed state shown in FIG. 3 and on the second carrier part body 68 in the open state shown in FIG. 4.

[0089] Similar to the switch 10 according to the first embodiment, the carrier body 44 or the second carrier part body 68 is spaced apart from the inner side 56 of the upper housing part 18 in the closed state of the switching mechanism 14 and rests against this inner side 56 in the open state of the switching mechanism 14. On the one hand, the two-part configuration of the carrier body 44 has the advantage that the second section 64, which serves as a counterholder for the bimetallic element 38 in the open state of the switching mechanism 14, can be produced more easily. On the other hand, the two-part configuration of the carrier body 44 also has kinematic advantages, since the bimetallic element 38 and the spring element 46 then act on different part bodies 66, 68 of the carrier body 44 in the open state of the switching mechanism 14.

[0090] It is understood that various further modifications can be made to the switch 10 without leaving the spirit and scope of the present disclosure. For example, the housing 12 can have a different shape or a multi-part structure. The bimetallic element 38, the spring element 46, the connecting element 36 and the current transfer member 34 can also have a different shape and design than that shown in FIGS. 1-4 present.

[0091] It is to be understood that the foregoing is a description of one or more preferred exemplary embodiments of the invention. The invention is not limited to the particular embodiment(s) disclosed herein, but rather is defined solely by the claims below. Furthermore, the statements contained in the foregoing description relate to particular embodiments and are not to be construed as limitations on the scope of the invention or on the definition of terms used in the claims, except where a term or phrase is expressly defined above. Various other embodiments and various changes and modifications to the disclosed embodiment(s) will become apparent to those skilled in the art. All such other embodiments, changes, and modifications are intended to come within the scope of the appended claims.

[0092] As used in this specification and claims, the terms for example, e.g., for instance, such as, and like, and the verbs comprising, having, including, and their other verb forms, when used in conjunction with a listing of one or more components or other items, are each to be construed as open-ended, meaning that the listing is not to be considered as excluding other, additional components or items. Other terms are to be construed using their broadest reasonable meaning unless they are used in a context that requires a different interpretation.