Temperature-dependent switching mechanism and temperature-dependent switch having such switching mechanism

Abstract

The invention relates to a temperature-dependent switching mechanism (10) for a temperature-dependent switch (100), comprising: a bimetallic element (12); a spring element (14); an electrically conductive contact part (16), which is arranged on the spring element (14) or is fixed to the spring element (14); and at least one retaining claw (18) provided at the spring element (14) or fixed to the spring element (14) wherein the at least one retaining claw (18) comprises a support surface (34); wherein the bimetallic element (12) is configured to quickly switch from a low temperature configuration to a high temperature configuration when a response temperature is exceeded, and wherein the bimetallic element (12) is supported on the support surface (34) in its high temperature configuration.

Description

Technical Field

[0001] The invention relates to a temperature-dependent switching mechanism for a temperature-dependent switch. The invention also relates to a temperature-dependent switch having such a temperature-dependent switching mechanism. Background Art

[0002] In principle, a large number of temperature-dependent switching mechanisms and switches having such temperature-dependent switching mechanisms are already known. Exemplary temperature-dependent switching mechanisms and switches are disclosed in DE 10 2011 119 632 B3, DE 10 2022 118 405 B3 and DE 10 2013 017232 A1.

[0003] Such temperature-dependent switches are used in a manner known in principle to monitor the temperature of a device. For this purpose, the switch is in 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 a switching mechanism arranged inside the switch.

[0004] The switch is usually electrically connected in series to the power circuit of the device to be protected via a connecting cable so that the power current of the device to be protected flows through the switch when the response temperature of the switch is lowered.

[0005] In the switch disclosed in DE 10 2011 119 632 B3, the switching mechanism is arranged inside the switch housing. The switch housing is formed by two parts. It includes a lower part, which is firmly connected to the cover part by an insulating foil, and the insulating foil is inserted between the lower part and the cover part. The temperature-dependent switching mechanism arranged in the switch housing includes a spring element and a bimetallic element, to which a movable contact part is fixed, and a bimetallic element is placed on the movable contact part. The spring element presses the movable contact part against a fixed opposing contact part arranged inside the switch housing at the cover part. The outer edge of the spring element constructed as a quick-turn spring disk is supported in the lower part of the switch housing, so that the current flows from the lower part through the quick-turn spring disk and the movable contact part into the fixed opposing contact part, and flows from the fixed opposing contact part into the cover part.

[0006] The temperature-dependent bimetallic element in the case of the switch disclosed in DE 10 2011 119 632 B3 and generally referred to as a bimetallic snap disk is a disk-shaped element which is essentially responsible for the temperature-dependent switching behavior of the switching mechanism. Such bimetallic elements are generally constructed as multilayer, active, sheet-like devices consisting of two, three or four interconnected parts with different thermal expansion coefficients. The connection of the individual metal or metal alloy layers in a bimetallic element of this type is generally a material-locked or positively locked connection and is achieved, for example, by rolling.

[0007] This bimetallic element has a first stable geometric configuration (low temperature configuration) at a low temperature below the response temperature of the bimetallic element, and has a second stable geometric configuration (high temperature configuration) at a high temperature above the response temperature of the bimetallic element. The bimetallic element switches rapidly from its low temperature configuration to its high temperature configuration in a temperature-dependent manner with hysteresis.

[0008] Therefore, if the temperature of the bimetallic element rises above the response temperature of the bimetallic element due to a temperature rise in the device to be protected, the bimetallic element snaps from its low temperature configuration to its high temperature configuration. The bimetallic element thus acts on the spring element in such a way that it lifts the movable contact part from the fixed counter-contact part, so that the switch opens and the device to be protected is turned off and can no longer be heated.

[0009] Unless a reset lock is provided, as the device to be protected cools down, the bimetallic element will snap back to its cold configuration as soon as its temperature drops below its so-called reset temperature, causing the switch to close again.

[0010] In its low temperature configuration, the bimetallic element is preferably mounted in a mechanically stress-free manner in the switch housing, wherein the bimetallic element is also not used to carry current. This has the advantage that the bimetallic element has a longer service life and the switching point (i.e. the response temperature or switching temperature of the bimetallic element) does not change even after many switching cycles.

[0011] In the case of a large number of temperature-dependent switches, the bimetallic element is therefore preferably inserted into the switch housing as a loose, separate component during the manufacture of the switch, wherein the bimetallic element is placed above the contact element fixed to the spring element, for example by means of a central through hole provided in the bimetallic element. Only by closing the switch housing can the bimetallic element be fixed in its position and its position relative to the other parts of the switching mechanism be defined. However, the production of such switches, into which the bimetallic element is inserted separately, has proven to be relatively cumbersome, since the insertion of the switch into the switch housing requires several steps. Therefore, such switches are generally difficult to produce automatically.

[0012] In the switch disclosed in DE 10 2011 119 632 B3, the bimetallic element is therefore connected to a contact part (outside the switch housing) which is previously fixed to a spring element. For this purpose, the bimetallic element is placed above the contact part and then the upper collar of the contact part is bent. As a result, not only is the spring element fixed to the contact part, but the bimetallic element is also retained on the contact part in a trapped manner.

[0013] Thus, the switching mechanism consisting of the bimetallic element, the spring element and the contact part can be manufactured in advance as a semi-finished product which forms a trapped unit and can be stored separately as bulk material. When manufacturing the switch, the switching mechanism can then be inserted into the switch housing as a trapped unit in just one working step. This greatly simplifies the production of the switch.

[0014] In the switch disclosed in DE 10 2011 119 632 B3, the spring element is welded or soldered to the contact part in order to achieve the best possible electrical contact between the two parts. However, it has been shown that the welded or soldered connection between the contact part and the spring element can break, in particular when the switch is stored in bulk as a semi-finished product. Of course, such a defective switch cannot be inserted again. In particular, such a defect can only be detected after the switch has been assembled, because only then can the function of the switching mechanism be tested, which is problematic.

[0015] In particular, the latter points have been improved in the switching mechanism disclosed in DE 10 2022 118 405 B3. The switching mechanism disclosed in this document comprises an additional switching mechanism housing, in which the switching mechanism unit including the bimetallic element, the spring element and the contact part is retained in a trapped manner in the additional switching mechanism housing, but with a gap. This additional switching mechanism housing not only enables the switching mechanism to be pre-produced as a semi-finished product, but also protects the fragile parts of the switching mechanism from damage, especially during storage. This also simplifies the installation of the switching mechanism in the switch. In addition, the additional switch housing has the advantage that the switching mechanism can be functionally tested before the switching mechanism is installed in the switch, because the quick-turning behavior of the bimetallic element can already be tested in the switch housing.

[0016] A similar advantageous solution is disclosed in DE 10 2013 017 232 A1. The temperature-dependent switching mechanism disclosed therein comprises an annular frame in which the bimetallic element and the spring element are retained in a trapped manner. This design can also protect the fragile components of the switching mechanism during storage. In addition, the switching mechanism can be functionally tested even before it is installed in a switch or a switching mechanism housing.

[0017] Although the latter two solutions in particular have proven to be advantageous, there is still room for further improvement. In particular, the manufacturability of the switching mechanism can be improved and its size can be further reduced. Furthermore, further simplifications and improvements should save additional costs. Summary of the invention

[0018] The object of the present invention is therefore to provide a temperature-dependent switching mechanism in which in particular the above-mentioned points are further improved. In particular, the object is to provide a temperature-dependent switching mechanism which can be pre-produced as a semi-finished product and stored as bulk material, whereby it is not easily damaged and thus does not lead to defects in the switching mechanism. However, the switching mechanism pre-produced as a semi-finished product should be as easy as possible to use in the temperature-dependent switch and should be able to be manufactured with as few working steps as possible. It should also be possible to test the function of the switching mechanism before installing it in the switch.

[0019] According to the invention, this object is achieved by a temperature-dependent switching mechanism, which has: - Bimetallic elements; - spring elements; - an electrically conductive contact part, which is arranged at the spring element or is fixed to the spring element; and - at least one retaining claw, which is arranged at the spring element or is fixed to the spring element, wherein the at least one retaining claw comprises a support surface; wherein the bimetallic element is configured to snap from a low temperature configuration to a high temperature configuration when a response temperature is exceeded, and wherein the bimetallic element is supported on the support surface in its high temperature configuration.

[0020] Therefore, the switching mechanism according to the present invention comprises one or more retaining claws, which are arranged at or fixed to the spring element and are used to retain the bimetallic element. The at least one retaining claw is not only used to retain the bimetallic element to prevent the bimetallic element from falling off the switching mechanism, but also used to protect the bimetallic element during bulk storage of the switching mechanism.

[0021] The at least one retaining claw comprises a support surface on which the bimetallic element is supported in its high temperature configuration. This has the advantage that a functional test of the switching mechanism according to the invention can be performed even before the switching mechanism according to the invention is installed in a switch. The bimetallic element can assume its two states / configurations (low temperature configuration and high temperature configuration) within the switching mechanism without the need for further parts.

[0022] Compared to the switching mechanism of the prior art mentioned at the beginning, the switching mechanism according to the invention is significantly more compact and simpler, in particular consists of fewer parts. Due to the provision of at least one retaining claw, a switching mechanism housing as proposed in DE 10 2022 118 405 B3 is no longer necessary. According to the invention, since at least one retaining claw is arranged at the spring element, for example formed integrally with the spring element, or fixed to the spring element, the switching mechanism according to the invention is also significantly smaller or more compact than the switching mechanism disclosed in DE 10 2022 118 405 B3.

[0023] According to the invention, an annular frame as proposed in DE 10 2013 017 232 A1 is also no longer necessary. Instead, at least one retaining claw is used in the switching mechanism according to the invention. Due to the support surface arranged on the retaining claw, the bimetallic element according to the invention can be supported directly on the retaining claw in its high-temperature configuration, which is also advantageous compared to the switching mechanism disclosed in DE 10 2013 017 232 A1, in which the bimetallic element is supported directly on the spring element in its high-temperature configuration. This particularly relieves the spring element, which makes the switching mechanism more durable overall.

[0024] Therefore, the above mentioned objects are fully achieved.

[0025] In a development, the bimetallic element, the spring element and the contact part form a switching mechanism unit which is held together in a trapped manner.

[0026] As a result, the individual components of the switching mechanism unit can no longer come loose from one another. On the one hand, this has the advantage that the switching mechanism can be pre-produced as a semi-finished product and can be stored more easily and more reliably as bulk material or on a conveyor belt. In addition, the switching mechanism and all its individual components can be inserted as a whole into the switch housing, which simplifies the assembly of the switch and thus makes it easier to automate.

[0027] In a further development, the bimetallic element is held in a trapped manner on the contact part and / or in a trapped manner on the spring element by means of the at least one holding claw.

[0028] This prevents the bimetallic element from being lost, in particular during storage on a belt or as bulk material. It also ensures that the bimetallic element does not fall out of the switching mechanism when the switching mechanism is installed and used in a switch. The most mechanically stable and safest way of holding the bimetallic element is achieved if the bimetallic element is trapped and held at the contact part by at least one retaining claw and is trapped and held at the spring element.

[0029] In a further development, the at least one retaining claw protrudes unilaterally from a first side of the spring element facing the bimetallic element.

[0030] In other words, the at least one retaining claw protrudes from the spring element on the same side on which the bimetallic element is arranged. The advantage of at least one retaining claw protruding on one side is that the embodiment of the switching mechanism is as space-saving as possible.

[0031] In the case of a plurality of retaining claws, these preferably all protrude on one side from the same side (first side) of the spring element.

[0032] In a further development, the at least one retaining claw protrudes from the first side of the spring element in a first direction, wherein the supporting surface is oriented transversely to the first direction and faces the spring element.

[0033] In the present case, the term "transverse" does not necessarily mean an orthogonal or perpendicular orientation. Instead, it is understood to refer to any type of orientation that is not parallel. Thus, an inclined orientation with an angle not equal to 0° also falls under the term "transverse".

[0034] According to the above improvement, the at least one retaining claw preferably includes a first portion and a second portion, the first portion protruding from the spring element and extending in a first direction, the second portion connected to the first portion, extending transversely to the first portion, and the support surface is arranged on the second portion so that the support surface faces the spring element. Particularly preferably, the at least one retaining claw has an inverted (upside down) L cross-sectional shape.

[0035] In another refinement, the at least one retaining claw comprises at least two retaining claws.

[0036] According to this improvement, the at least two retaining claws are preferably arranged at a distance from each other on the spring element. Particularly preferably, the at least two retaining claws according to this improvement are each at the same distance from the central axis of the spring element. In the case of three or more retaining claws, these retaining claws are preferably arranged evenly distributed on the spring element so that rotational symmetry around the central axis is produced.

[0037] Embodiments of multiple individual retaining claws are generally easier to manufacture and more cost-effective than a relatively large, continuous retaining claw that, for example, extends along the entire circumference of the bimetallic element or along a majority of the circumference of the bimetallic element (i.e., more than 50% of the circumference of the bimetallic element).

[0038] In a further development, the at least one retaining claw is connected integrally to the spring element or the at least one retaining claw is fixed to the spring element in a material-locked manner.

[0039] Thus, for example, the at least one retaining claw can be formed in one piece with the spring element. Alternatively, the at least one retaining claw is preferably welded or soldered to the spring element. This forms a mechanically very stable retaining claw that is inseparably connected to the spring element.

[0040] In a further development, the spring element comprises an outer edge, wherein the at least one retaining claw is spaced apart from the outer edge.

[0041] Preferably, the outer edge is a peripheral edge, from which the at least one retaining claw is spaced. Particularly preferably, the at least one retaining claw has a smaller distance from the center axis of the spring element than the outer edge of the spring element. In other words, the at least one retaining claw is preferably offset radially inwardly relative to the outer edge of the spring element, which spring element can be, for example, disc-shaped, in particular circular disc-shaped.

[0042] This has the advantage that the switching mechanism according to the invention can be very easily fixed in the switch housing of the switch when the switch is installed, since the outer edge of the spring element can be clamped between the two parts of the switch housing to fix the switching mechanism. This does not impair the function of the at least one retaining claw.

[0043] In a further development, the outer edge lies in a plane and the radial inner region of the spring element is curved.

[0044] This further simplifies the fixing of the switching mechanism in the switch housing.In addition, the curved inner region of the spring element provides the spring element with sufficient freedom of movement so that the spring element can move together with the bimetallic element during a switching operation.

[0045] In another refinement, the spring element has a first configuration when the bimetallic element is in its low temperature configuration, wherein the spring element is placed into a second configuration by the bimetallic element when the bimetallic element snaps to its high temperature configuration.

[0046] Preferably, the spring element is a snap-action spring disk, which, like the bimetallic element, has two different configurations or states. It is particularly preferred that the two configurations / states of the spring element are mechanically stable configurations / states. However, unlike the two configurations of the bimetallic element, the two configurations / states of the spring element are temperature-independent.

[0047] In a further development, the spring element together with the at least one retaining claw forms an open housing, in which the bimetallic element is arranged but can be accessed from the outside, wherein the open housing at least partially surrounds the bimetallic element from a first side, a second side and a circumferential side, the second side being opposite to the first side, and the circumferential side extending between the first side and the second side and transversely to the first side and the second side.

[0048] As a result, the bimetallic element is arranged to a certain extent enclosed in a housing formed by the spring element and the at least one retaining claw. This provides good protection for the bimetallic element, which is advantageous in particular when the switching mechanism is stored in bulk. A "housing" of this type preferably at least partially surrounds the bimetallic element from all sides, while the bimetallic element can still be accessed from the outside, which is very important for the function of the switching mechanism.

[0049] In a further development, the open housing formed by the spring element together with the at least one retaining claw comprises an opening on the second side, the inner diameter of the opening being smaller than the outer diameter of the bimetallic element measured parallel to the bimetallic element.

[0050] This ensures in a simple manner that the bimetallic element cannot be released from the at least one retaining claw. Therefore, the bimetallic element is retained at the spring element in a trapped manner.

[0051] In another refinement, the switching mechanism is rotationally symmetric about the central axis.

[0052] This also simplifies the installation of the switching mechanism, since the switching mechanism can be inserted into the switch housing of the switch in any orientation relative to its central axis. In addition, the symmetrical orientation of the switching mechanism ensures an optimal force distribution when the switch is closed.

[0053] In another refinement, the bimetallic element comprises an opening through which the contact part protrudes. The bimetallic element is preferably disc-shaped. The above-mentioned opening is preferably inserted centrally in the bimetallic element, wherein the bimetallic element is placed above the contact part through the opening.

[0054] In a further development, the spring element preferably contains an electrically conductive material.

[0055] This has the advantage that the spring element can be used as a conductive part so that the current flows through the spring element when the switch is closed. When the switch is closed, the current does not have to flow through the bimetallic element, which reduces the load on the bimetallic element and has a positive effect on the service life of the bimetallic element.

[0056] As already mentioned at the outset, the invention relates not only to a temperature-dependent switching mechanism, but also to a temperature-dependent switch in which a switching mechanism according to the invention is inserted. It should be understood that the above-mentioned refinements and the features defined in the dependent claims relate not only to the switching mechanism according to the invention, but in the same way also to the switch according to the invention.

[0057] In a development of the temperature-dependent switch, the temperature-dependent switch comprises a switch housing, the temperature-dependent switching mechanism is arranged in the switch housing, and the switch housing comprises a lower part and a cover part, wherein the spring element is clamped between the lower part and the cover part. Preferably, the outer edge of the spring element is clamped between the lower part and the cover part of the switch housing. As a result, the switch is relatively easy to install and mechanically stable.

[0058] It is to be understood that the features mentioned above and those yet to be explained below can be used not only in the combination indicated in each case but also in other combinations or on their own, without departing from the scope of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] Embodiments of the invention are shown in the drawings and are explained in more detail in the following description. The drawings show: Figure 1 is a schematic cross-sectional view of a temperature-dependent switching mechanism according to a first embodiment of the present invention, wherein the switching mechanism is in a first switching state; Figure 2 yes Figure 1 A schematic cross-sectional view of a temperature-dependent switching mechanism shown, wherein the switching mechanism is in a second switching state; Figure 3 is a schematic cross-sectional view of a temperature-dependent switching mechanism according to a second embodiment of the present invention, wherein the switching mechanism is in its first switching state; Figure 4 is a schematic plan view of a spring element that can be used in a temperature-dependent switching mechanism according to the present invention; Figure 5 is a schematic cross-sectional view of a temperature dependent switch according to an embodiment of the present invention, wherein the switch is in its low temperature state; Figure 6 yes Figure 5A schematic cross-sectional view of a temperature dependent switch is shown wherein the switch is in its high temperature state; Figure 7 is a schematic cross-sectional view of a temperature dependent switch according to another embodiment of the present invention, wherein the switch is in its low temperature state; and Figure 8 yes Figure 7 A schematic cross-sectional view of a temperature-dependent switch is shown, wherein the switch is in its high temperature state. DETAILED DESCRIPTION

[0060] Figure 1 and Figure 2 A schematic cross-sectional view of a first embodiment of a switching mechanism according to the present invention is shown. Figure 1 The low temperature state of the switching mechanism is shown. Figure 2 The high temperature state of the switching mechanism is shown. The switching mechanism is denoted in its entirety by the reference numeral 10 in each case.

[0061] The switching mechanism 10 is a temperature-dependent switching mechanism. The switching mechanism 10 has a multi-component design. The switching mechanism 10 comprises a bimetallic element 12 , a spring element 14 , an electrically conductive contact component 16 and at least one retaining claw 18 .

[0062] As the name implies, the bimetallic element 12 contains a bimetallic element. The spring element 14 and the contact member 16 are made of a conductive material, preferably a metal. Preferably, the at least one retaining claw 18 is also made of a metal. However, the at least one retaining claw 18 does not necessarily have to be made of a conductive material; the at least one retaining claw 18 may also be made of a non-conductive material.

[0063] exist Figure 1 and Figure 2 In the illustrated embodiment, the bimetallic element 12 is substantially disc-shaped. Therefore, the bimetallic element 12 is also referred to as a bimetallic disc. Due to its physical properties, the bimetallic element 12 is sometimes also referred to as a bimetal snap-action disc.

[0064] In the illustrated embodiment, the bimetallic element 12 includes a central opening 20 with which the bimetallic element 12 is placed over the contact member 16. Figure 1 and Figure 2 In the illustrated embodiment, the bimetallic element 12 is placed over the contact member 16 through its opening 20 without being securely connected to the contact member 16. In other words, the bimetallic element 12 and the contact member 16 are loosely coupled to each other at this point and are able to move relative to each other.

[0065] In the present embodiment, the contact part 16 is fixed to the spring element 14. More precisely, in this embodiment, the contact part 16 is connected to the spring element 14 in a material-locked manner. For example, the contact part 16 is welded or soldered to the spring element 14. For better centering, the contact part 16 comprises an extension 22 at its end, with which the contact part 16 is inserted into an opening 24 arranged centrally in the spring element 14. The contact part 16 comprises a collar 26 approximately in the middle, with the bottom side of which the contact part 16 lies flat on the top side of the spring element 14. The material-locked connection between the spring element 14 and the contact part 16 is preferably provided on the bottom side of the collar 26. The collar 26 provided on the contact part 16 also serves to support the bimetallic element 12 in the high-temperature configuration (see Figure 2 ), as will be explained in more detail below.

[0066] It should be noted at this point that the contact part 16 can also be connected integrally to the spring element 14, rather than being connected in a material-locked manner. In other words, the spring element 14 and the contact part 16 can be formed in one piece. In this case, the contact part 16 is preferably formed as a raised part protruding from the top side of the spring element 14.

[0067] At least one retaining claw 18 is arranged in the region of an outer edge 28 of the spring element 14. Figure 1 and Figure 2 In the embodiment shown, the at least one retaining claw is fixed to the spring element 14 in a material-locking manner, for example by welding or soldering.

[0068] At least one retaining claw 18 protrudes unilaterally from a top side 30 of the spring element 14, which in the present case is also referred to as a first side 30 of the spring element 14. The first side 30 of the spring element 14 is the side of the spring element 14 facing the bimetallic element 12.

[0069] More precisely, at least one retaining claw 18 protrudes from a first side 30 of the spring element 14 in a first direction 32 corresponding to Figure 1 and Figure 2 A support surface 34 is provided on the inner side of at least one retaining claw 18. The support surface 34 extends transversely, preferably perpendicularly to the first direction 32. In the high temperature state, the bimetallic element 12 is supported on the support surface 34 with its outer edge 36, as will be explained in more detail below (see Figure 2 ).

[0070] It can be said that the spring element together with the at least one retaining claw 18 forms a partially open housing in which the bimetallic element 12 is arranged and retained, but can be accessed from the outside. This open housing formed by the spring element 14 and the at least one retaining claw 18 surrounds a first side 38 of the bimetallic element 12, as well as an opposite second side 40 of the bimetallic element and a peripheral side 42 of the bimetallic element, the first side 38 facing the first side 30 of the spring element 14, the peripheral side 42 of the bimetallic element extending in each case at least partially transversely to the first side 38 of the bimetallic element and the second side 40 of the bimetallic element. The open housing formed by the spring element 14 together with the at least one retaining claw 18 comprises, on the side facing the second side 40 of the bimetallic element 12, an opening 44 through which the movable contact part 16 is accessible to the outside.

[0071] The inner diameter of the opening 44 is smaller than the outer diameter of the bimetallic element 12 measured parallel to the bimetallic element 12. This ensures that the bimetallic element 12 is trapped and held on the spring element 14 by the at least one holding claw 18. The bimetallic element 12, the spring element 14 and the contact part 16 thus form a switching mechanism unit that is trapped and held together.

[0072] exist Figure 1 In the low temperature state of the switching mechanism 10 shown, the bimetallic element 12 is convexly curved on its second side 40 (the top side of the bimetallic element 12 ). Figure 1 In the low temperature state shown, the radial inner region 46 of the spring element 14 is convexly curved on its first side 30 (the top side of the spring element 14). In other words, in the low temperature state of the switching mechanism 10, both the bimetallic element 12 and the radial inner region 46 of the spring element 14 are curved upward (see Figure 1 ). In this displacement position, the bimetallic element 12 rests loosely from above on the collar 26 of the contact part 16. The free outer edge 36 of the bimetallic element 12 is hardly stressed and preferably does not come into contact with the spring element 14 and / or the at least one retaining claw 18.

[0073] If, starting from this switching state of the switching mechanism 10, the temperature of the switching mechanism 10 now rises to a temperature higher than the response temperature of the bimetallic element 12, the bimetallic element 12 will Figure 1 The low temperature state shown is fast forward to Figure 2The high temperature state is shown. The second side 40 of the bimetallic element 12 (the top side of the bimetallic element 12) is now bent concavely. As a result, the bimetallic element 12 is supported with its outer edge 36 on the support surface 34, which is arranged on the at least one retaining claw 18. At the same time, the bimetallic element 12 presses the contact part 16 with its inner edge 48 in the direction of the spring element 14. In other words, both the bimetallic element 12 and the spring element 14 are bent downwards, so that not only the bimetallic element 12 is now bent concavely on its second side 40 (top side), but also the spring element 14 is now bent concavely on its first side 30 (top side).

[0074] Since at least one retaining claw 18 acts as an abutment member in the high temperature state of the switching mechanism 10, wherein the bimetallic element 12 can be supported on the at least one retaining claw 18, and the switching mechanism 10 and its devices 12, 14, 16, 18 also form a switching mechanism unit that is trapped and held together in the low temperature state, the switching mechanism 10 can also be functionally checked without other devices, and in particular, the switching mechanism 10 does not need to be installed in a temperature-dependent switch. Figure 1 and Figure 2 The switching mechanism 10 shown thus forms a separately functional, storable semi-finished product.

[0075] Figure 3 A second embodiment of a switching mechanism 10 according to the present invention is shown in a schematic cross-sectional view. The basic structure and operation mode of the switching mechanism 10 are similar to those of Figure 1 and Figure 2 The first embodiment shown does not differ. The basic design of the switching mechanism 10 is also at least similar to that of the first embodiment. However, one difference is that at least one retaining claw 18 is integrally connected to the spring element 14 or at least one retaining claw 18 is integrally formed with the spring element 14. Preferably, the spring element 14 and the at least one retaining claw 18 are formed from thin metal sheets.

[0076] Figure 3 Another difference of the second embodiment shown is that the contact part 16 is designed here as a rivet, which is connected to both the bimetallic element 12 and the spring element 14. Figure 3 In the second embodiment shown, the bimetallic element is therefore not only retained by at least one retaining claw 18 on the spring element, but also retained by the contact part 16. The support ring 50 can be arranged between the bimetallic element 12 and the spring element 14 on the contact part 16, which is designed as a rivet. However, the latter is not absolutely necessary.

[0077] Figure 4 The top view from above shows Figure 3The spring element 14 of the embodiment of the switching mechanism 10 shown. It can be seen from this that the spring element 14 is essentially disc-shaped, in which various recesses 52 are provided in order to reduce the resistance and save material. Instead of a (single) retaining claw 18 extending completely around the circumference, three retaining claws 18 are provided here, which are distributed and arranged at a certain distance from each other. More precisely, the three retaining claws are regularly distributed around the circumference of the spring element 14. It should be understood that in principle, two or more retaining claws 18 can also be provided. Similarly, only a single retaining claw 18 can also be used as an abutment for the bimetallic element 12, as long as the at least one retaining claw 18 extends over a larger part of the circumference of the spring element 14.

[0078] The at least one retaining claw 18 is preferably arranged at a distance from the outer edge 28 of the spring element 14. Adjacent to the outer edge 28, the spring element 14 preferably comprises a peripheral edge region 58 which lies in a plane, i.e. is flat or planar. The radially inner region 46 of the spring element 14 is curved. Figure 4 In the illustrated embodiment, the radially inner region 46 is formed by three radially extending webs 54 and a central region 56 .

[0079] The flat or planar outer edge region 58 of the spring element 14 offers the advantage of an attachment and fixing that is as simple as possible within the temperature-dependent switch, as will be explained in more detail below.

[0080] The spring element 14 is rotationally symmetrical about the center axis 60. Similarly, the entire switching mechanism 10 is also preferably rotationally symmetrical about the center axis 60. Therefore, the switching mechanism 10 can be inserted into the switch housing of the switch at any position rotated about the center axis 60. This simplifies the assembly of the switching mechanism 10 many times.

[0081] Figure 5 and Figure 6 A first embodiment of a temperature-dependent switch is shown in which the switching mechanism 10 according to the invention is used. Figure 5 The low temperature state of the switch is shown. Figure 6 The high temperature state of the switch is shown. In each case, the switch is designated in its entirety by reference numeral 100. The switch 100 comprises a switch housing 62, which serves as a housing for the switching mechanism 10. The switch housing 62 comprises a pot-shaped lower part 64 and a cover part 66, which is held on the lower part 64 by its bent or flanged upper edge.

[0082] exist Figure 5 and Figure 6In the embodiment shown, both the lower part 64 and the cover part 66 are made of a conductive material, preferably metal. An insulating foil 68 is arranged between the lower part 64 and the cover part 66. The insulating foil 68 provides electrical insulation between the lower part 64 and the cover part 66. The insulating foil 68 also provides a mechanical seal, which prevents liquid or impurities from entering the interior of the housing from the outside.

[0083] Since the lower part 64 and the cover part 66 are each made of a conductive material, thermal contact with the electrical device to be protected can be established through their outer surfaces. The outer surfaces can also be used for electrical connections of the switch 100. For example, the outer surface 65 of the lower part 64 can be used as a first electrical terminal of the switch 100, and the outer surface 67 of the cover part 66 can be used as a second electrical terminal of the switch 100.

[0084] The switching mechanism 10 is arranged to be clamped between the lower part 64 and the cover part 66. More precisely, the switching mechanism 10 is arranged to be clamped between the spacing ring 70 and the cover part 66. For this purpose, the outer edge region 58 of the spring element 14 rests on the spacing ring 70 and is clamped by the cover part 66 from the opposite side.

[0085] Furthermore, the switching mechanism 10 rests with its at least one retaining claw 18 against the inner circumference of the spacer ring 70. By means of the spacer ring 70, the switching mechanism 10 can thus be fixed and centered. As a result, the movable contact part 16 of the switching mechanism 10 is oriented relative to the fixed counter-contact part 72 arranged inside the lower part 64 of the switch housing 62. In the present case, the counter-contact part 72 is also referred to as a fixed contact part.

[0086] exist Figure 5 In the low temperature state of the switch 100 shown, which is also referred to as the closed state of the switch 100, the switching mechanism 10 establishes an electrically conductive connection between the lower part 64 and the cover part 66 and thereby between the two external connection surfaces 65, 67 of the switch 100. The electrically conductive contact between the two external connection surfaces 65, 67 of the switch 100 is established in particular by the spring element 14 and the movable contact part 16 interacting with the fixed contact part 72. The contact pressure between the movable contact part 16 and the fixed contact part 72 is generated by the spring element 14. In this state, the bimetallic element 12 is stored in the switching mechanism 10 in a more or less stress-free manner.

[0087] If the temperature of the device to be protected and thus the temperature of the switch 100 now rises to or above the switching temperature of the bimetallic element 12, the bimetallic element 12 switches from Figure 5 The low temperature state shown is fast forward to Figure 6Its high temperature state is shown. During this snap action, the bimetallic element 12 is supported with its outer edge 36 on the support surface 34 provided on at least one retaining claw 18 and presses the movable contact part 16 upward with its inner edge 48 together with the spring element 14. As a result, the spring element 14 is simultaneously bent upward with its center, whereby the movable contact part 16 is lifted away from the fixed contact portion 72. The circuit is thus interrupted and the switch 100 is thereby opened.

[0088] If the device to be protected and thus the switch 100 together with the bimetallic element 12 then cools down again, when the reset temperature (which is also referred to as the switching back temperature) is reached, the bimetallic element 12 snaps back to its low temperature state, e.g. Figure 5 This allows for a reversible switching behavior.

[0089] Of course, the switch 100 can also be prevented from switching back after the switch 100 has been quickly transferred to the high temperature state by a corresponding locking device. A large number of such locking devices are known from the prior art, and they are particularly used to prevent a one-time switch from switching back.

[0090] Figure 7 and Figure 8 Another embodiment of the switch 100 according to the present invention is shown, again in the low temperature state ( Figure 7 ) and the high temperature state of the switch 100 ( Figure 8 ) is shown in a schematic cross-sectional view below.

[0091] Here, the shape of the spacer ring 70' is slightly different. Figure 5 and Figure 6 A significant difference to the embodiment shown is that the counter-contact 72 is not designed as a fixed contact here, but is arranged on a counter-spring element 74. This counter-spring element 74 allows optimal compensation of manufacturing tolerances. On the other hand, in the closed state of the switch (see Figure 7 ), the contact pressure can be increased because the opposing spring element 74 resists the spring element 14 and thereby increases the force with which the two contact portions 16, 72 are pressed together. However, the switching principle is otherwise the same as previously described with reference to Figure 5 and Figure 6 The switching principle described in the illustrated embodiment remains the same.

[0092] It will be appreciated that various further modifications may be made to the switching mechanism 10 itself and to the switch housing 62 without departing from the scope of the invention. Furthermore, the shape of the at least one retaining claw shown in the present case can be varied almost at will, which is why the term "retaining claw" is to be interpreted broadly in the present case. Functionally, the at least one retaining claw 18 serves as a retainer for the bimetallic element 12, on which the bimetallic element 12 can be supported with its edge 36, in particular in the high temperature state of the switching mechanism 10.

Claims

1. A temperature-dependent switching mechanism (10) for a temperature-dependent switch (100), comprising: - bimetallic element (12); - a spring element (14); - an electrically conductive contact member (16) which is arranged at the spring element (14) or is fixed to the spring element (14); and - at least one retaining claw (18), which is arranged at the spring element (14) or is fixed to the spring element (14), wherein the at least one retaining claw (18) comprises a support surface (34); in, The bimetallic element (12) is configured to snap from a low temperature configuration to a high temperature configuration when a response temperature is exceeded, and wherein the bimetallic element (12) is supported on the support surface (34) in its high temperature configuration.

2. The temperature-dependent switching mechanism (10) according to claim 1, wherein: The bimetallic element (12), the spring element (14) and the contact component (16) form a switching mechanism unit that is trapped and held together.

3. The temperature-dependent switching mechanism (10) according to claim 1, wherein: The bimetallic element (12) is retained by the at least one retaining claw (18) on the contact component (16) and / or retained by the spring element (14) in a trapped manner.

4. The temperature-dependent switching mechanism (10) according to claim 1, wherein: The at least one retaining claw (18) protrudes unilaterally from a first side (30) of the spring element (14) facing the bimetallic element (12).

5. The temperature-dependent switching mechanism (10) according to claim 4, wherein: The at least one retaining claw (18) protrudes from the first side (30) of the spring element (14) in a first direction (32), and wherein the support surface (34) is oriented transversely to the first direction (32) and faces the spring element (14).

6. The temperature-dependent switching mechanism (10) according to claim 1, wherein: The at least one retaining claw (18) comprises at least two retaining claws.

7. The temperature-dependent switching mechanism (10) according to claim 1, wherein: The at least one retaining claw (18) comprises a single retaining claw (18) extending at least along a majority of the circumference of the spring element (14), or along the entire circumference of the spring element (14).

8. The temperature-dependent switching mechanism (10) according to claim 1, wherein: The at least one retaining claw (18) is connected integrally to the spring element (14), or the at least one retaining claw (18) is fixed to the spring element (14) in a material-locked manner.

9. The temperature-dependent switching mechanism (10) according to claim 1, wherein: The spring element (14) comprises an outer edge (28), and the at least one retaining claw (18) is spaced apart from the outer edge (28).

10. The temperature-dependent switching mechanism (10) according to claim 9, wherein: The outer edge (28) lies in a plane and the radial inner region (46) of the spring element (14) is curved.

11. The temperature-dependent switching mechanism (10) according to claim 1, wherein: The spring element (14) together with the at least one retaining claw (18) forms an open housing, in which the bimetallic element (12) is arranged but can be accessed from the outside, wherein the open housing at least partially surrounds the bimetallic element (12) from a first side (38), a second side and a circumferential side (42), the second side being opposite to the first side (38), and the circumferential side (42) extending between the first side (38) and the second side (40) and transversely to the first side (38) and the second side (40).

12. The temperature-dependent switching mechanism (10) according to claim 11, wherein: The open housing formed by the spring element (14) together with the at least one retaining claw (18) comprises an opening (44) on the second side (40), the inner diameter of the opening (44) being smaller than the outer diameter of the bimetallic element (12) measured parallel to the bimetallic element (12).

13. The temperature-dependent switching mechanism (10) according to claim 1, wherein: The switching mechanism (11) is rotationally symmetrical about a central axis (60), and wherein the bimetallic element (12) comprises a central opening (20) through which the contact part (16) protrudes.

14. A temperature-dependent switch (100) having a temperature-dependent switching mechanism according to any one of claims 1 to 13.

15. The temperature-dependent switch (100) according to claim 14, wherein The switch (100) comprises a switch housing (62), in which the temperature-dependent switching mechanism (10) is arranged, and the switch housing (62) comprises a lower part (64) and a cover part, wherein the spring element (14) is clamped between the lower part (64) and the cover part (66).

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