Temperature-dependent switch

Abstract

A temperature-dependent switch (10) with a temperature-dependent switching mechanism (14) and a housing (12) accommodating the switching mechanism (14), on which a first stationary contact (26) and a second stationary contact (28) are arranged. The temperature-dependent switching mechanism (14) is configured to switch the switch (10) temperature-dependently between a closed position, in which the switching mechanism (14) establishes an electrically conductive connection between the first and the second stationary contact (26, 28), and an open position, in which the switching mechanism (14) breaks the electrically conductive connection. The switching mechanism (14) comprises a carrier body (44) movable in the housing (12), a spring element (46) supporting the carrier body (44), a bimetallic element (38) arranged in the carrier body (44), and a current transmission element (34).The current transfer element (34) is held securely on the bimetallic element (38) by a connecting element (36) that is separate from the carrier body (44). In the closed position, the current transfer element (34) is pressed against the first and second stationary contacts (26, 28) to establish the electrically conductive connection, and in the open position, it is lifted away from the first and second stationary contacts (26, 28) to break the electrically conductive connection.

Description

[0001] The present invention relates to a temperature-dependent switch.

[0002] The starting point for the present invention is a switch known to the applicant, which is shown in a schematic sectional view in Fig. 5 and 6 This is shown. Another exemplary temperature-dependent switch is disclosed in DE 197 08 436 A1.

[0003] Such temperature-dependent switches serve, in a manner known per se, to monitor the temperature of a device. For this purpose, the switch is brought into thermal contact with the device to be protected, for example, via one of its outer surfaces, so that the temperature of the device to be protected influences the temperature of the switching mechanism located inside the switch.

[0004] The switch is electrically connected in series to the supply circuit of the device to be protected via connecting leads using its external electrical connections, so that below a response temperature of the switch the supply current of the device to be protected flows through the switch.

[0005] A temperature-dependent switching mechanism integrated into the switch ensures temperature-dependent switching behavior. This mechanism is typically located between two electrodes / contacts, each of which is electrically connected to one of the two external terminals. The temperature-dependent switching behavior is designed such that below the switch's response temperature or the response temperature of the switching mechanism, the switch is in a closed position, in which the mechanism establishes an electrically conductive connection between the two contacts / external terminals of the switch. When the response temperature of the switching mechanism is exceeded, the switch switches to an open position, in which the electrically conductive connection between the two contacts / external terminals is broken.

[0006] In this way, the temperature-dependent switching device ensures that, in its closed position (below the switch's response temperature), it closes the power supply circuit of the protected device, and in its open position (above the switch's response temperature), it interrupts the power supply circuit. Thus, such a temperature-dependent switch ensures that an electrical device is automatically de-energized and therefore switched off in the event of unwanted overheating.

[0007] Such temperature-dependent switches therefore offer protection against overheating in electrical devices of all kinds.

[0008] The temperature-dependent switching behavior of the switch mechanism is usually primarily due to a temperature-dependent bimetallic element, which is designed to change its geometric shape depending on its temperature. When the switch's response temperature is reached and / or exceeded, this temperature-dependent bimetallic element changes its geometric shape in such a way that it moves the switch mechanism from its closed position to its open position.

[0009] Typically, this bimetallic element is a multilayered, active, sheet-like component made up of two, three, or more interconnected components with different coefficients of thermal expansion. The connection between the individual layers of metals or metal alloys in such bimetallic elements is usually either metallurgical or form-fit, achieved, for example, by rolling. The bimetallic element can also be designed as a trimetallic element, which is why the term "bimetallic element" here also extends to the latter trimetallic elements, i.e., any element made up of two or more interconnected metallic components with different coefficients of thermal expansion.

[0010] Such a bimetallic element exhibits a first stable geometric configuration (low-temperature configuration) at low temperatures, below the switch's response temperature (which corresponds to the bimetallic element's response temperature), and a second stable geometric configuration (high-temperature configuration) at high temperatures, above the bimetallic element's response temperature. The temperature-dependent bimetallic element thus switches between its low-temperature and high-temperature configurations, and vice versa, depending on the temperature, in a hysteresis-like manner.

[0011] If the temperature of the temperature-dependent bimetallic element increases beyond the response temperature of the bimetallic element as a result of a temperature increase in the device to be protected, it snaps from its low-temperature configuration to its high-temperature configuration, thus moving the switching mechanism from its closed position to its open position, thereby interrupting the current flow through the switch.

[0012] If the temperature of the switch and thus also of the temperature-dependent bimetallic element subsequently drops below a so-called return temperature of the bimetallic element as a result of the cooling of the device to be protected, the bimetallic element changes its geometric shape again from its high-temperature configuration to its low-temperature configuration, so that the switching mechanism is brought back into its closed position, so that current can flow through the switch again.

[0013] Typically, such temperature-dependent bimetallic elements are designed so that their return temperature (mentioned above) is lower than their response temperature. However, the temperature-dependent switching behavior can also be designed so that its return temperature is in the same temperature range or even exactly the same as its response temperature.

[0014] In addition to the temperature-dependent bimetallic element, an additional spring element is often used in the switching mechanisms of such temperature-dependent switches. This spring element generates, or at least contributes to generating, the mechanical closing pressure of the switching mechanism in the closed position. The spring element is a temperature-independent spring element, preferably made of metal. This spring element relieves the bimetallic element, particularly in the closed position of the switching mechanism, as the latter then has to exert less force, or even no force at all, to generate the mechanical closing pressure.

[0015] At the in Fig. 5 and 6In addition to the switch shown and the switch known from DE 197 08 436 A1, the switching mechanism further comprises a current transfer element that functions as a type of contact bridge. In the closed position, this element rests directly against both contacts of the switch to establish the electrically conductive connection between them. This has the particular advantage that the current transfer element is the only component of the switching mechanism through which current flows in the closed position. Both the bimetallic element and the spring element can be de-energized.

[0016] This has a beneficial effect on the service life of the bimetallic element and the spring element, and also enables the use of such switches in electrical devices that are operated with high currents.

[0017] The in Fig. 5 and 6The switch 100 shown has a housing 110 with a cup-shaped lower part 112, into which a temperature-dependent switching mechanism 114 is inserted. The lower part 112 is closed by a top part 116, which is held against the lower part 112 by its raised rim. The lower part 112 can be made of metal or insulating material, while the top part 116 is always made of insulating material.

[0018] The upper part 116 contains two rivets 118, 120, whose inner heads serve as stationary contacts for the switching mechanism 114. The outer heads of the two rivets 118, 120 serve as external terminals of the switch 100, to which, for example, connecting wires, terminal plates, or other connecting cables can be attached for the electrical connection of the switch 100.

[0019] The switching mechanism 114 has an annular current transfer element 122 serving as a contact bridge. This current transfer element 122 is located in the Fig. 5 The closed position of switch 100 shown is connected to the two stationary contacts 118, 120, thereby establishing an electrically conductive connection between these two stationary contacts 118, 120. In the Fig. 6 In the open position of the switch 100 shown, the current transmission element 122 is lifted off from the two stationary contacts 118, 120, so that the electrically conductive connection between these two contacts 118, 120 is separated.

[0020] The temperature-dependent switching behavior of the switch 100 is essentially caused by a disc-shaped bimetallic element 124, which is coupled to the current transmission element 122 via a carrier body 126. The carrier body 126 is supported by a spring element 128 located in the lower part 112 of the switch 100 and is pressed upwards towards the upper part 116. The spring element 128 causes in the Fig. 5 The closed position of the switch 100 shown thus determines the closing pressure with which the current transmission element 122 is pressed against the two stationary contacts 118, 120. In this closed position of the switch 100, the bimetallic element 124 is essentially free of force mounted in the support body 126.

[0021] Upon reaching the response temperature, the bimetallic element 124 snaps out of its position. Fig. 5 shown low-temperature configuration in its Fig. 6 The high-temperature configuration shown changes and opens the switch or disconnects the electrically conductive connection between the two stationary contacts 118, 120.

[0022] More precisely, the bimetallic element 124 rests with its outer edge against the spring-loaded support body 126 and comes into contact with its center on a projection formed centrally on the upper part 116 and extending from it into the interior of the switch 100, which acts as a kind of plunger 130. This causes the bimetallic element 124 to push the support body 126, together with the current transmission element 122 clamped therein, downwards against the force of the spring element 128, thereby lifting the current transmission element 122 away from the two stationary contacts 118, 120.

[0023] However, it has become apparent that this design of the switching mechanism 114 has several disadvantages. For one thing, the bimetallic element 124 must be in the open position ( Fig. 6 ) exert a comparatively high force on a permanent basis, exceeding the force of the spring element 128 to keep the switch 100 open. This can lead to safety risks, particularly as the bimetallic element 124 ages and the force it exerts decreases. Furthermore, the design of the plunger 130 on the underside of the upper part 116 also leads to several disadvantages. Firstly, it necessitates a central hole in the current transmission element 122 through which the plunger 130 protrudes. Understandably, this weakens the material of the current transmission element 122, resulting in a lower mass and ultimately lower electrical conductivity. Secondly, a hard impact of the bimetallic element 124 against the plunger 130 can damage the bimetallic element 124.Furthermore, the production of the upper part 116 with such a plunger 130 is comparatively complex compared to conventional, purely plate-shaped upper parts.

[0024] It is therefore an object of the present invention to provide a temperature-dependent switch with which the aforementioned disadvantages can be overcome. In particular, it is an object to achieve an increase in performance by increasing switching reliability and electrical conductivity, and to improve the design of the switch.

[0025] This problem is solved according to the invention by a temperature-dependent switch according to claim 1. The temperature-dependent switch according to the invention comprises a temperature-dependent switching mechanism and a housing for the switching mechanism, in which a first stationary contact and a second stationary contact are arranged. The temperature-dependent switching mechanism is configured to switch the switch, depending on the temperature, between a closed position, in which the switching mechanism establishes an electrically conductive connection between the first and the second stationary contact, and an open position, in which the switching mechanism breaks the electrically conductive connection. 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 transmission element.The current transfer element is securely held to the bimetallic element by a connecting element designed separately from the carrier body. In the closed position, this current transfer element is pressed against the first and second stationary contacts to establish the electrically conductive connection, and in the open position, it is lifted away from the first and second stationary contacts to break the electrically conductive connection.

[0026] The switch according to the invention therefore has, similar to the one in Fig. 5 and 6 The switch shown has a carrier body movable within the housing and spring-mounted by the spring element, in which the bimetallic element is arranged. Unlike the one in Fig. 5 and 6In the switch shown, however, the bimetallic element is not connected to the current transmission element via the carrier body, but rather via a connecting element designed separately from it, ensuring it is not lost.

[0027] This has the following advantages in particular: A plunger projecting inwards from the upper part of the switch housing is not required. Accordingly, the current transmission element does not need to be weakened by a comparatively large hole. The current transmission element can therefore be designed with a comparatively large mass. This, in turn, allows for greater current conductivity. The bimetallic element is no longer subjected to as much stress, since it does not strike a plunger or other object when the switch is opened. In addition, the inventive design of the switching mechanism relieves stress on the bimetallic element in the open position of the switch, since the bimetallic element does not have to press continuously against the spring element supporting the carrier body in the open position. This, in turn, increases switching reliability. The design of the housing, especially the upper part of the housing, is, compared to the one in Fig. 5 and 6 The switch shown is also simplified due to the elimination of the plunger.

[0028] The above-mentioned task is therefore completely solved.

[0029] According to one embodiment, the spring element is configured to exert a force acting in a first direction on the carrier body in both the closed and open positions, and the bimetallic element is configured to exert a force acting in a first direction on the current transmission element in the closed position to press the current transmission element against the first and second stationary contacts, and to exert a second force acting in a direction opposite to the first direction on the current transmission element in the open position to lift the current transmission element away from the first and second stationary contacts.

[0030] In the closed position of the switch, the spring element and the bimetallic element exert forces in the same direction (referred to here as the "first direction"). The spring element pushes the carrier body, and thus also the bimetallic element located within it, towards the two stationary contacts in the first direction. The bimetallic element, in turn, pushes the current-carrying element towards the two stationary contacts in the first direction. Thus, in the closed position of the switch, the spring element and the bimetallic element together generate the closing pressure.

[0031] In the open position, the force exerted by the bimetallic element on the current transfer element acts in the opposite direction to the force exerted by the spring element on the carrier body. Even in the closed position, the spring element continues to push the carrier body towards the two stationary contacts in the first direction, while the bimetallic element pushes or lifts the current transfer element away from the two stationary contacts.

[0032] In other words, when switching between the closed and open positions, the bimetallic element changes the direction of the force it exerts on the current transfer element. The spring element, on the other hand, exerts a force in the same direction (first direction) on the carrier body in both the closed and open positions.

[0033] According to a further embodiment, the carrier body is designed in an annular or cup shape. Preferably, the carrier body is rotationally symmetrical and has at least on its upper surface facing the two stationary contacts a central opening in which the bimetallic element, the current transfer element, and the connecting element linking these two are arranged. In the case of the annular design of the carrier body, this opening is designed as a through-hole.

[0034] It should be noted that "ring-shaped" in this context does not necessarily imply circular. Instead, it refers to any type of solid of revolution, whose cross-section can be of any shape.

[0035] Such a ring- or cup-shaped support body can be arranged inside the switch housing in a very space-saving manner, without increasing the overall dimensions of the switch. Furthermore, the ring- or cup-shaped support body improves the mechanical and electrical shielding of the other switchgear components.

[0036] The support body is preferably made of an electrically insulating material.

[0037] This has the advantage that the bimetallic element is electrically insulated from the spring element. Therefore, neither the bimetallic element nor the spring element carries current when the switch is closed. Furthermore, this allows the carrier body to be designed with a comparatively low mass, which in turn has a positive effect on the service life of the spring element supporting the carrier body.

[0038] On the other hand, if a higher stiffness and mass of the support body is desired, this can in principle also be produced from an electrically conductive material, e.g. metal.

[0039] It is further preferred that the support body at least partially surrounds a circumferential edge of the bimetallic element. Particularly preferably, the support body completely surrounds the circumferential edge of the bimetallic element.

[0040] The carrier body thus provides additional protection for the bimetallic element inside the switch housing.

[0041] It is further preferred that the carrier body also at least partially surrounds a circumferential edge of the current transmission element without touching the current transmission element or its circumferential edge.

[0042] Unlike the one in Fig. 5 and 6In the switch shown, the current transmission element is not clamped in the carrier body or rigidly connected to it. Instead, the circumferential edge of the current transmission element is spaced away from the carrier body. Consequently, the current transmission element can move relative to the carrier body, thus increasing its freedom of movement.

[0043] For example, it is preferred that the current transmission element moves relative to the carrier body when the temperature-dependent switching mechanism switches the switch between the closed and open positions. It is particularly preferred that the current transmission element and the carrier body move in opposite directions when switching from the closed to the open position or vice versa. This results in advantageous kinematics during switching between the closed and open positions.

[0044] According to a further embodiment, the spring element presses the support body against an inner side of the housing in the open position. In the open position, the support body rests against the inner side of the housing with one of its sides that is opposite the side of the support body where the spring element engages the support body.

[0045] The support body is thus braced against the inside of the housing. This limits the spring travel of the spring element. Furthermore, this has the advantage that the force exerted by the spring element is transferred into the housing when the derailleur is in the open position; unlike the design in [the other design], the bimetallic element does not need to be [further specified] in the open position. Fig. 5 and 6 The switch shown thus does not work against the force of the spring element to lift the current transmission element from the two stationary contacts. This has a very positive effect on the switching reliability of the switch according to the invention.

[0046] In the closed position, however, the support body is preferably spaced away from the inside of the housing.

[0047] This has the advantage that the force exerted by the spring element on the carrier body, together with the force exerted by the bimetallic element, creates the closing pressure. The spring element and the bimetallic element are mechanically connected in series in the closed position.

[0048] According to a further embodiment, the bimetallic element is designed as a bimetallic disc which, in the closed position, supports itself with its circumferential edge against a first section of the carrier body in order to press the current transfer element against the first and the second stationary contact, and which, in the open position, supports itself with its circumferential edge against a second section of the carrier body, which is spaced apart from the first section, in order to lift the current transfer element away from the first and the second stationary contact.

[0049] The bimetallic element is thus supported by its circumferential edge against the carrier body in both the closed and open positions of the switching mechanism. The bimetallic element can, for example, be designed in the shape of a circular disc. This support against the carrier body in both the closed and open positions, in turn, ensures advantageous kinematics of the switching mechanism when switching between these positions.

[0050] Preferably, the first and second sections, against which the bimetallic disc is supported with its circumferential edge, are arranged opposite each other and on opposite sides of the bimetallic disc.

[0051] The bimetallic disc can thus be designed in a conventional manner, such that it snaps from a convex or concave low-temperature configuration into a correspondingly reversed concave or convex high-temperature configuration upon reaching its response temperature.

[0052] The second section, against which the bimetallic disc rests in the open position of the switch mechanism, can, for example, be designed by a radially inwardly projecting part of the carrier body that reduces the inner diameter of the carrier body section by section. This part of the carrier body can be formed, for example, by a knurled surface, a bead, or a radially inwardly projecting lug.

[0053] According to a further embodiment, the support body is designed in multiple parts and has a first support part body and a second support part body loosely resting on the first support part body, wherein the first section is arranged on the first support part body and the second section is arranged on the second support part body.

[0054] This design has the advantage that the two sections on which the bimetallic disc rests with its outer circumferential edge are easier to manufacture. This also simplifies the manufacture of the support body itself. Both support body sections are preferably ring-shaped. Furthermore, the two support body sections are preferably interlockable.

[0055] The two-part design of the carrier body also has kinematic advantages, since in the open position the spring element acts on the first carrier part body, while the bimetallic disc acts on the second carrier part body.

[0056] According to a further embodiment, the connecting element by means of which the bimetallic element is fastened to the current transmission element has a rivet. This rivet is preferably passed through an opening arranged centrally in the bimetallic element and the current transmission element. The rivet ensures a captive connection between the current transmission element and the bimetallic element, whereby the bimetallic element is held securely but with some play against the rivet. This guarantees sufficient mobility of the bimetallic element, which is particularly necessary when switching between the closed and open positions of the switching mechanism.

[0057] According to a further embodiment, the housing has a lower part and an upper part held on the lower part, wherein the first and the second stationary contact are arranged on the upper part and the spring element is clamped between the lower part and the support body.

[0058] It is understood that the phrase "the upper part is held to the lower part" refers to both active and passive holding. In other words, it can mean either that the upper part is held by the lower part or vice versa. The only important thing is that the two parts of the housing are held together.

[0059] Preferably, both the lower and upper parts are made of electrically insulating material. For example, the lower and upper parts can be made of plastic. However, it is particularly preferred that the lower and / or upper part be made of ceramic.

[0060] It is particularly advantageous if the top part, on which the two stationary contacts are located, is made of ceramic. Ceramic has a significantly higher melting point than plastic. This considerably minimizes the risk of outgassing, which in the worst case can lead to an explosion of the switch due to arcing, compared to a plastic cover. Furthermore, a ceramic top part provides improved sealing in the area of ​​the two stationary contacts. With plastic top parts, on the other hand, capillary action can easily draw solder into the switch's interior when the external connections are attached to or soldered to the stationary contacts on the top part.

[0061] It is understood that the features mentioned above and those to be explained below can be used not only in the combinations specified, but also in other combinations or on their own, without leaving the scope of the present invention.

[0062] Exemplary embodiments of the present invention are shown in the drawings and are explained in more detail in the following description. The drawings show: Fig. 1 a schematic sectional view of a first embodiment of the switch according to the invention, wherein the temperature-dependent switching mechanism of the switch is in its closed position; Fig. 2 a schematic sectional view of the in Fig. 1 Figure 1 shows an embodiment of the switch according to the invention, wherein the temperature-dependent switching mechanism of the switch is in its open position; Figure 3 shows a schematic sectional view of a second embodiment of the switch according to the invention, wherein the temperature-dependent switching mechanism of the switch is in its closed position; Figure 4 shows a schematic sectional view of the Fig. 3 The embodiment of the switch according to the invention is shown in Figure 1, wherein the temperature-dependent switching mechanism of the switch is in its open position; Figure 5 is a schematic sectional view of a switch that forms a starting point for the present invention, wherein the temperature-dependent switching mechanism of the switch is in its closed position; and Figure 6 is a schematic sectional view of the switch shown in Figure 1. Fig. 5 shown switch, wherein the temperature-dependent switching mechanism of the switch is in its open position.

[0063] Fig. 1-4 Two embodiments of the temperature-dependent switch according to the invention are shown, wherein Fig. 1 and 3 each show the closed position of the switch and Fig. 2 and 4 Each diagram shows the open position of the switch. The entire switch is marked with the reference number 10.

[0064] The switch 10 has a housing 12 in which a temperature-dependent switching mechanism 14 is arranged.

[0065] 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 a top part 18, which is held against the lower part 16 by its raised rim 20.

[0066] 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 to offer the highest possible heat resistance and to present a lower risk of outgassing compared to plastic.

[0067] 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 through-contacts that penetrate the upper part 18 and to whose upper surfaces the external electrical connections 30, 32 can be connected. For example, the external connections 30, 32, in the form of wires, terminal blocks, or other electrical connecting leads, are soldered to the sections of the rivets 22, 24 that protrude upwards from the upper part 18.

[0068] The two stationary contacts 26, 28 are associated with a current transmission element 34, which is designed as a circular contact bridge. The current transmission element 34 is coupled in a captive manner to a bimetallic element 38, which is also designed as a circular bridge, by means of a connecting element 36. The connecting element 36 is designed as a rivet that passes through a hole provided centrally in the current transmission element 34 and is preferably fixedly connected to the current transmission element 34.

[0069] The bimetallic element 38 is held securely, but with some play, on the rivet 36. The rivet 36 is passed through a hole provided centrally in the bimetallic element 38, the bimetallic element 38 being held securely, but with some play, with its inner edge 40 between the current transmission element 34 and a bearing shoulder 42 of increased diameter formed on the underside of the rivet 36.

[0070] In addition to the current transmission element 34, the connecting element 36, and the bimetallic element 38, the switching mechanism 14 also comprises a support body 44 and a spring element 46 supporting the support body 44. The support body 44 serves in particular as a carrier for the part of the switching mechanism 14 comprising the current transmission element 34, the connecting element 36, and the bimetallic element 38. The support body 44 can either be detachably mounted on the spring element 46 or be bonded to the spring element 46.

[0071] The support body 44 is designed as an essentially ring-shaped body of revolution that surrounds the circumferential outer edge 48 of the bimetallic element 38. The circumferential side 50 of the support body 44 can bear against the inner circumferential side 52 and be guided slidably on it. Depending on the embodiment, however, it is also possible for the circumferential side 50 of the support body 44 to be arranged at a distance from the inner circumferential side 52, so that the support body 44 then has no contact with the lower part 16 of the housing 12.

[0072] Unlike the bimetallic element 38, the current transfer element 34 has no direct contact with the carrier body 44. The circumferential edge 54 of the current transfer element 34 is spaced away from the inner wall of the carrier body 44. Accordingly, the current transfer element 34 is movable relative to the carrier body 44 without collision.

[0073] The support body 44 is movably mounted within the housing 12. The in Fig. 1 In the closed position of the switching mechanism 14 shown, the spring element 46 is pushed upwards towards an inner side 56 of the upper part 18 of the housing 12. As shown Fig. 1 As can be seen, the support body 44 is spaced away from the inner surface 56 of the housing upper part 18 in the closed position of the switching mechanism 14. At the same time, the bimetallic element 38, with its circumferential rim 48, bears against the support body 44 and, with its inner rim 40, presses the current transmission element 34 upwards against the two stationary contacts 26, 28. More precisely, the bimetallic element 38, with its circumferential rim 48, bears against a first section 60 of the support body 44.

[0074] In the closed position of the switching mechanism 14, the spring element 46 and the bimetallic element 38 together exert the contact pressure with which the current transmission element 34 is pressed against the two stationary contacts 26, 28. The spring element 46 and the bimetallic element 38 are located in the Fig. 1 The closed position shown is mechanically connected in series. The force exerted by the spring element 46 on the support body 44 acts in the same direction 58 (upwards) as the force exerted by the bimetallic element 38 on the current transmission element 34. This direction, indicated by an arrow 58, is referred to here as the "first direction".

[0075] Starting from the point in Fig. 1 In the situation shown, in which the switching mechanism 14 is in its closed position and establishes the electrically conductive connection between the two contacts 26, 28 via the current transmission element 34, if the temperature exceeds the response temperature of the bimetallic element 38, the bimetallic element 38 snaps from its position in Fig. 1 shown, convex high-temperature configuration in its Fig. 2 The concave low-temperature configuration shown is reversed. The bimetallic element 38 pushes the riveted connecting element 36 and the current transmission element 34 firmly connected to it downwards in the direction of arrow 62, thereby lifting the current transmission element 34 away from the contacts 26, 28 and interrupting the electrically conductive connection between the two contacts 26, 28.

[0076] The bimetallic element 38 thus exerts a force on the connecting element 36 and the current transmission element 34, acting in a second direction 62 opposite to the first direction 58. For this purpose, the bimetallic element 38 is supported by its circumferential outer edge 48 against a second section 64 of the support body 44. This second section 64 is located on the opposite side of the bimetallic element 38 compared to the first section 60. The second section 64 is in the Fig. 1 and 2 In the illustrated embodiment, the element is formed 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 position of the switching mechanism 14.

[0077] In the Fig. 2 In the open position of the switching mechanism 14 shown, the bimetallic element 38 exerts a force in the second direction 62 on the connecting element 36 and thus also indirectly on the current transmission element 34, while the spring element 46 continues to exert a force on the support body 44, acting in the opposite first direction 58. As a result, the current transmission element 34 is pulled downwards by the contacts 26, 28 due to the high-temperature configuration of the bimetallic element 38, but the support body 44 is pushed upwards until its upper surface rests against the inner or lower surface 56 of the housing upper part 18. Thus, the support body 44 is in the position shown. Fig. 2 The open position of the switching mechanism 14 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 support body 44 therefore does not reduce the force exerted by the bimetallic element 38 on the connecting element 36.

[0078] The carrier body 44 therefore moves during the switching process, in which the switching mechanism 14 is moved from its position due to temperature. Fig. 1 shown closing position in the Fig. 2 When the spring element 46 is brought into the open position shown, it moves upwards along the first direction 58, while the current transmission element 34 simultaneously moves downwards in the opposite direction 62. Switching from the closed position to the open position thus results in a partial release or expansion of the spring element 46.

[0079] Fig. 3 and 4Figure 1 shows a second embodiment of the switch 10 according to the invention, which differs essentially in the design of the carrier body 44. The remaining components of the switch housing 12 and the switching mechanism 14 do not differ from those shown in Figure 1. Fig. 1 and 2 The first embodiment shown is described and will therefore not be explained again.

[0080] Fig. 3 shows the closed position of switch 10. Fig. 4 shows the open position of switch 10.

[0081] The carrier body 44 is located in the Fig. 3 and 4 The second embodiment of the switch 10 shown is designed in two parts. The carrier body 44 has a first carrier part 66 and a second carrier part 68. Both carrier parts 66, 68 are loosely connected to each other.

[0082] Both support body sections 66 and 68 are designed as ring-shaped bodies of revolution. The second support body section 68 is placed on or attached to the first support body section 66. The first support body section 66 has a cross-section that is essentially L-shaped. The second support body section 68 has a cross-section that is essentially the inverse of an L-shape.

[0083] In the Fig. 3 In the closed position shown, the bimetallic element 38 is supported with its circumferential outer edge 48 against the first section 60 formed on the first support body 66. The second section 64 of the support body 44, against which the circumferential edge 48 of the bimetallic element 38 rests in the position shown in Fig. 4 The bimetallic element 38, which is supported in the closed position shown, is arranged on the second support body 68 according to the second embodiment. Thus, the bimetallic element 38 is supported in the position shown in Fig. 3 shown closing position on the first support body 66 and in the Fig. 4 shown opening position on the second support body 68.

[0084] Similar to the switch 10 according to the first embodiment, the support body 44, or the second support part 68, is spaced from the inner surface 56 of the housing upper part 18 in the closed position of the switching mechanism 14 and rests against this inner surface 56 in the open position of the switching mechanism 14. The two-part design of the support body 44 has the advantage that the second section 64, which serves as a counter-holder for the bimetallic element 38 in the open position of the switching mechanism 14, is easier to manufacture. Furthermore, the two-part design of the support body 44 also has kinematic advantages, since the bimetallic element 38 and the spring element 46 then engage different sub-bodies 66, 68 of the support body 44 in the open position of the switching mechanism 14.

[0085] It is understood that various further modifications can be made to the switch 10 according to the invention without departing from the scope of the present invention. For example, the housing 12 can be shaped differently or be constructed in multiple parts. The bimetallic element 38, the spring element 46, the connecting element 36, and the current transmission element 34 can also have different shapes and designs than shown in the present illustration. Fig. 1-4 shown here.

Claims

1. A temperature-dependent switch (10), having a temperature-dependent switching mechanism (14) and a housing (12) in which the switching mechanism (14) is arranged and on which a first stationary contact (26) and a second stationary contact (28) are arranged, wherein the temperature-dependent switching mechanism (14) is configured to switch the switch (10) in a temperature-dependent manner between a closed state, in which the switching mechanism (14) establishes an electrically conductive connection between the first and the second stationary contact (26, 28), and an open state, in which the switching mechanism (14) disconnects the electrically conductive connection, wherein the switching mechanism (14) comprises a spring element (46), a bimetallic element (38), and a current transfer member (34) which is held in a captive manner on the bimetallic element (38) by a connecting member (36), wherein the current transfer member (34) is pressed against the first and second stationary contacts (26, 28) in the closed state in order to establish the electrically conductive connection, and is lifted off the first and second stationary contacts (26, 28) in the open state in order to disconnect the electrically conductive connection, characterized in that: - the switching mechanism (14) comprises a carrier body (44) movable in the housing (12), - the spring element (46) supports the carrier body, - the bimetallic element (38) is arranged in the carrier body (44), and - the connecting element (36) is provided separate to the carrier body (44).

2. The temperature-dependent switch according to claim 1, wherein in the closed state and in the open state the spring element (46) is configured to exert on the carrier body (44) a force acting in a first direction, wherein in the closed state the bimetallic element (38) is configured to exert on the current transfer member (34) a force acting in the first direction in order to press the current transfer member (34) against the first and second stationary contacts (26, 28), and wherein in the open state the bimetallic element (38) is configured to exert on the current transfer member (34) a force acting in a second direction opposite to the first direction in order to lift the current transfer member (34) off the first and second stationary contacts (26, 28).

3. The temperature-dependent switch according to claim 1 or 2, wherein the carrier body (44) is ring-shaped or pot-shaped.

4. The temperature-dependent switch according to any one of claims 1-3, wherein the carrier body (44) is made of an electrically insulating material.

5. The temperature-dependent switch according to any one of claims 1-4, wherein the carrier body (44) at least partially surrounds a circumferential edge (48) of the bimetallic element (38).

6. The temperature-dependent switch according to any one of claims 1-5, wherein the carrier body (44) at least partially surrounds a circumferential edge (54) of the current transfer member (34) without touching it.

7. The temperature-dependent switch according to any one of claims 1-6, wherein the current transfer member (34) moves relative to the carrier body (44) when the temperature-dependent switching mechanism (14) switches the switch (10) between the closed state and the open state.

8. The temperature-dependent switch according to any one of claims 1-7, wherein in the open state the spring element (46) presses the carrier body (44) against an inner side (56) of the housing (12).

9. The temperature-dependent switch according to claim 8, wherein in the closed state the carrier body (44) is spaced from the inner side (56) of the housing (12).

10. The temperature-dependent switch according to any one of claims 1-9, wherein the bimetallic element (38) is configured as a bimetallic disc which, in the closed state, is supported with its circumferential edge (48) against a first section (60) of the carrier body (44) in order to press the current transfer member (34) against the first and second stationary contacts (26, 28), and which, in the open state, is supported with its circumferential edge (48) against a second section (64) of the carrier body (44), which is spaced apart from the first section (60), in order to lift the current transfer member (34) off the first and second stationary contacts (26, 28).

11. The temperature-dependent switch according to claim 10, wherein the first and second sections (60, 64) are opposite to each other and arranged on opposite sides of the bimetallic disc (38).

12. The temperature-dependent switch according to claim 10 or 11, wherein the carrier body (44) composed of several parts and comprises a first carrier part body (66) and a second carrier part body (68) loosely arranged on the first carrier part body (66), wherein the first section (60) is arranged on the first carrier part body (66) and the second section (64) is arranged on the second carrier part body (68).

13. The temperature-dependent switch according to any one of claims 1-12, wherein the connecting element (36) comprises a rivet.

14. The temperature-dependent switch according to any one of claims 1-13, wherein the housing (12) comprises a lower part (16) and an upper part (18) held on the lower part (16), wherein the first and second stationary contacts (26, 28) are arranged on the upper part (18) and the spring element (46) is clamped between the lower part (16) and the carrier body (44).

15. The temperature-dependent switch according to claim 14, wherein the lower part (16) and the upper part (18) are made of electrically insulating material.

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