EP4465327A1 - Temperature-dependent switching device and temperature-dependent switch with such a switching device - Google Patents

Abstract

Temperature-dependent switching mechanism (10) for a temperature-dependent switch (100), with a temperature-dependent bimetallic snap disk (16), a temperature-independent spring snap disk (18), an electrically conductive contact part (20) on which the bimetallic snap disk (16) and the spring snap disk (18) are held captive, so that the bimetallic snap disk (16), the spring snap disk (18) and the contact part (20) form a switching mechanism unit (12) held together captively, and a switching mechanism housing (14) in which the switching mechanism unit (12) is arranged and which holds the switching mechanism unit (12) captively. The derailleur housing (14) surrounds the derailleur unit (12) from a first housing side (22), a second housing side (24) opposite the first housing side (22) and a housing peripheral side (26) running between and transversely to the first and second housing sides (22, 24). The derailleur housing (14) is designed as an at least partially open housing and has an opening (28) on the first housing side (22) through which the contact part (20) is accessible from outside the derailleur housing (14).

Description

The present invention relates to a temperature-dependent switching mechanism for a temperature-dependent switch. The present invention further relates to a temperature-dependent switch with such a temperature-dependent switching mechanism.

Temperature-dependent switches are already known in many different forms. An example of a temperature-dependent switch is shown in the DE 10 2011 119 632 B3 revealed.

Such temperature-dependent switches are used in a known manner to monitor the temperature of a device. To do this, 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 arranged inside the switch.

The switch is typically connected electrically in series via connecting cables into the supply circuit of the device to be protected, so that below the response temperature of the switch, the supply current of the device to be protected flows through the switch.

In the DE 10 2011 119 632 B3 In the known switch, the switching mechanism is arranged inside a switch housing. The switch housing is constructed in two parts. It has a lower part that is firmly connected to a cover part with an insulating film in between. The temperature-dependent switching mechanism arranged in the switch housing has a spring snap disk to which a movable contact part is attached, as well as a bimetal snap disk that is placed over the movable contact part. The spring snap disk presses the movable contact part against a stationary counter-contact that is arranged on the inside of the switch housing on the cover part. The spring snap disk is supported with its outer edge in the lower part of the switch housing, so that the electrical current from the lower part flows through the spring snap disk. and the movable contact part flows into the stationary counter contact and from there into the cover part.

The temperature-dependent bimetal snap disc is essentially responsible for the temperature-dependent switching behavior of the switch. This is usually designed as a multi-layer, active, sheet-metal component made of two, three or four interconnected components with different thermal expansion coefficients. The connection of the individual layers of metals or metal alloys in such bimetal snap discs is usually material-locking or form-locking and is achieved, for example, by rolling.

Such a bimetal snap disk has a first stable geometric configuration (low temperature configuration) at low temperatures, below the response temperature of the bimetal snap disk, and a second stable geometric configuration (high temperature configuration) at high temperatures, above the response temperature of the bimetal snap disk. The bimetal snap disk jumps from its low temperature configuration to its high temperature configuration depending on the temperature in the manner of a hysteresis.

If the temperature of the bimetal snap-action disc rises above the response temperature of the bimetal snap-action disc due to a temperature increase in the device to be protected, it snaps from its low-temperature configuration to its high-temperature configuration. The bimetal snap-action disc works against the spring snap-action disc in such a way that it lifts the moving contact part from the stationary counter-contact, so that the switch opens and the device to be protected is switched off and cannot heat up any further.

If no switch-back lock is provided, the bimetal snap-action disc snaps back into its low-temperature configuration so that the switch is closed again as soon as the temperature of the bimetal snap-action disc drops below the so-called return temperature of the bimetal snap-action disc as a result of the cooling of the device to be protected.

In its low-temperature configuration, the bimetal snap-action disk is preferably mounted in the switch housing without mechanical forces, whereby the bimetal snap-action disk is also not used to conduct the current. This has the advantage that the bimetal snap-action disk has a longer service life and that the switching point, i.e. the response temperature of the bimetal snap-action disk, does not change even after many switching cycles.

In a large number of temperature-dependent switches, the bimetal snap disc is therefore preferably inserted into the switch housing as a loose individual part during manufacture of the switch, with the bimetal snap disc being slipped over the contact part attached to the spring snap disc, for example with a central through hole provided in it. Only when the switch housing is closed is the bimetal snap disc then fixed in its position and its position relative to the other components of the switching mechanism determined. However, the production of such a switch in which the bimetal snap disc is inserted individually has proven to be relatively complicated, since several steps are necessary to insert the switch into the switch housing.

In the DE 10 2011 119 632 B3 In the known switch, the bimetal snap disc is therefore connected in advance (outside the switch housing) to the contact part attached to the spring snap disc. To do this, the bimetal snap disc is put over the contact part and then an upper collar of the contact part is folded over. As a result, not only is the spring snap disc attached to the contact part, but the bimetal snap disc is also held captive to it.

The switching mechanism, which consists of the bimetal snap disc, the spring snap disc and the contact part, can be manufactured in advance as a semi-finished product, which forms a captive unit and can be stored separately as bulk goods. When manufacturing the switch, the switching mechanism can then be inserted into the switch housing as a captive unit in just one step. This simplifies the production of the switch many times over.

The spring snap disk on the DE 10 211 119 632 B3 The known switch is welded or soldered to the contact part in order to create the best possible electrical contact between the two components. However, it has been shown that the welded and soldered connection between the contact part and the spring snap disk can break, particularly when the switchgear is stored in bulk as a semi-finished product. Such defective switches can then of course no longer be used. The particular problem is that such a defect can only be detected after the switch has been assembled, as only then is it possible to test the functionality of the switchgear.

Also in the DE 199 19 648 A1 A temperature-dependent switch is proposed whose switching mechanism can be produced in advance as a semi-finished product. In this switching mechanism too, the bimetal snap disk, the spring snap disk and the contact part form a captive unit before installation in the switch housing, which can be inserted into the switch housing as a whole during production of the switch and can be stored in advance as bulk goods. In this switching mechanism, the contact part has a jacket made of softer metal and a core made of electrically conductive, harder metal. The bimetal snap disk and the spring snap disk are plugged onto the jacket and molded into the softer metal of the jacket. However, it has been found that this type of connection often leads to the bimetal snap disk and/or the spring snap disk becoming accidentally detached from the contact part during storage of the switching mechanism.

Another possibility of pre-production of the rear derailleur as a semi-finished product is from the DE 29 17 482 A1 and the DE 10 2007 014 237 A1 The captive unit of the switching mechanism is achieved by connecting the bimetal snap disk and the spring snap disk with a rivet. Depending on the design of the switch, this rivet can also form the movable contact part of the switching mechanism. The rivet is constructed in two parts and has a rivet bolt that works together with a hollow rivet or a rivet bolt with a counterholder attached to it.

While this type of rivet connection between spring snap disc and bimetal snap disc has proven to be a mechanically long-lasting connection, However, the rivet connection leads to other disadvantages. The bimetal snap disk is usually clamped firmly to the rivet, which can lead to deformation and thus to malfunctions of the bimetal snap disk. Overall, it is therefore basically possible to store the switchgear in bulk. However, damage to the switchgear during bulk storage cannot be ruled out.

It is therefore an object of the present invention to provide a temperature-dependent switching mechanism that can be pre-produced as a semi-finished product and stored as bulk goods without being susceptible to damage that could lead to a defect in the switching mechanism. The switching mechanism pre-produced as a semi-finished product should then be as easy to use as possible in a temperature-dependent switch and enable its manufacture with as few work steps as possible. In addition, a functional test of the switching mechanism should be possible before it is installed in the switch.

• einer temperaturabhängigen Bimetall-Schnappscheibe;
• einer temperaturunabhängigen Feder-Schnappscheibe;
• einem elektrisch leitfähigen Kontaktteil, an dem die Bimetall-Schnappscheibe und die Feder-Schnappscheibe unverlierbar gehalten sind, so dass die Bimetall-Schnappscheibe, die Feder-Schnappscheibe und das Kontaktteil eine unverlierbar zusammengehaltene Schaltwerkseinheit bilden; und
• einem Schaltwerksgehäuse, in dem die Schaltwerkseinheit angeordnet ist und die Schaltwerkseinheit unverlierbar hält;

• wobei das Schaltwerksgehäuse die Schaltwerkseinheit von einer ersten Gehäuseseite, einer der ersten Gehäuseseite gegenüberliegenden zweiten Gehäuseseite und einer zwischen und quer zu der ersten und der zweiten Gehäuseseite verlaufenden Gehäuseumfangsseite zumindest teilweise umgibt, und
• wobei das Schaltwerksgehäuse als zumindest teilweise offenes Gehäuse ausgestaltet ist und auf der ersten Gehäuseseite eine Öffnung aufweist, durch die das Kontaktteil von außerhalb des Schaltwerksgehäuses zugänglich ist,
• wobei das Kontaktteil dauerhaft durch die Öffnung nach außen hindurch-ragt oder gemeinsam mit der Bimetall-Schnappscheibe und der Feder-Schnappscheibe innerhalb des Schaltwerksgehäuses derart beweglich ist, dass das Kontaktteil bei entsprechender Bewegung innerhalb des Schaltwerks-gehäuses durch die Öffnung nach außen hindurchragt, und
• wobei ein Durchmesser der Öffnung kleiner als ein parallel dazu gemessener Durchmesser der Bimetall-Schnappscheibe und kleiner als ein parallel dazu gemessener Durchmesser der Feder-Schnappscheibe ist.

This object is achieved according to the invention by a temperature-dependent switching mechanism, with:

• a temperature-dependent bimetal snap-action disk;
• a temperature-independent spring snap disk;
• an electrically conductive contact part on which the bimetallic snap-action disc and the spring snap-action disc are held captively, so that the bimetallic snap-action disc, the spring snap-action disc and the contact part form a switching unit held together captively; and
• a derailleur housing in which the derailleur unit is arranged and which holds the derailleur unit captive;

• wherein the derailleur housing at least partially surrounds the derailleur unit from a first housing side, a second housing side opposite the first housing side and a housing peripheral side extending between and transversely to the first and second housing sides, and
• wherein the derailleur housing is designed as an at least partially open housing and has an opening on the first housing side through which the contact part is accessible from outside the derailleur housing,
• wherein the contact part permanently projects outwards through the opening or is movable together with the bimetallic snap disc and the spring snap disc within the derailleur housing in such a way that the contact part projects outwards through the opening when moved accordingly within the derailleur housing, and
• wherein a diameter of the opening is smaller than a diameter of the bimetal snap-action disk measured parallel thereto and smaller than a diameter of the spring snap-action disk measured parallel thereto.

According to the invention, the derailleur therefore comprises an additional derailleur housing in which the derailleur unit, which has the bimetallic snap disc, the spring snap disc and the contact part, is held captive but with play.

Similar to the prior art cited at the beginning, the bimetallic snap-action disk, the spring snap-action disk and the contact part form a captively held together switching unit, which can be pre-produced as a semi-finished product before it is inserted into a temperature-dependent switch.

However, this derailleur unit is now also surrounded by a derailleur housing so that the fragile components of the derailleur, in particular the bimetal snap disk and the spring snap disk, are protected by the derailleur housing during bulk storage. Damage to these fragile components during bulk storage is largely ruled out as the fragile components of the derailleur are safely encapsulated in this derailleur housing.

However, the derailleur housing not only offers the advantage of safe storage of the fragile derailleur components during bulk storage, it also enables also a much simpler way of manufacturing the temperature-dependent switch in which the switching mechanism is later used.

Unlike a conventional switch housing, the additional switch housing is not a closed housing in which the switch is hermetically sealed, but a partially open housing that has an opening on the first side of the housing through which the contact part is accessible from outside the switch housing. The switch housing can therefore be inserted together with the switch housing as a unit into a simplified switch housing, which forms the final switch housing. A counter contact can be arranged on this switch housing, which interacts with the contact part of the switch that is accessible from the outside. No modification or further processing of the switch housing is necessary.

When manufacturing the temperature-dependent switch, the switching mechanism according to the invention can therefore initially be pre-produced together with the switching mechanism housing as a semi-finished product and then inserted as a whole into a switch housing. This not only simplifies the storage of the switch, but also the manufacture of the temperature-dependent switch.

Since all components of the switch are already arranged ready for use on the switchgear, which is pre-produced as a semi-finished product, the switch housing surrounding the switchgear housing only needs to have two contacts that are electrically connected to one another via the switchgear. No other complex components need to be provided on the switch housing. It is therefore also possible to insert the switchgear according to the invention directly into an external switch housing that is designed integrally with the device to be monitored and is constructed much more simply than conventional switch housings that hermetically seal the switchgear. Of course, it is also possible to insert the switchgear together with its switchgear housing into a conventional switch housing, as is the case, for example, with the DE 10 2011 119 632 B3 is known.

A further advantage of the switching mechanism according to the invention is that a functional test can be carried out before it is installed in the switch or switch housing. Due to the switch housing now provided, in which the switching mechanism unit is encapsulated, the snapping behavior of the bimetal snap disk can already be tested in the switching mechanism housing.

According to the invention, the contact part permanently projects outwards through the opening or is movable together with the bimetallic snap disc and the spring snap disc within the derailleur housing in such a way that the contact part projects outwards through the opening when there is a corresponding movement within the derailleur housing.

This guarantees easy access to the contact part from outside the derailleur housing. This simplifies the electrical connection and contacting of the derailleur in particular. The contact part is at least partially directly accessible from the outside, so that the switch housing of the switch to be ultimately manufactured only needs to have a first contact that is electrically connected to the derailleur housing and a second contact that acts as a counter contact to the contact part of the derailleur.

As already mentioned, the present invention relates not only to the temperature-dependent switching mechanism itself, but also to a temperature-dependent switch which, in addition to the temperature-dependent switching mechanism according to the invention, comprises a switch housing surrounding the switching mechanism, which has a first contact and a second contact, wherein the switching mechanism is designed to establish an electrical connection between the first and the second contact below a response temperature of the bimetallic snap disk and to interrupt the electrical connection when the response temperature is exceeded.

According to the invention, a diameter of the opening is smaller than a diameter of the bimetal snap-action disk measured parallel thereto and smaller than a diameter of the spring snap-action disk measured parallel thereto.

The derailleur unit, which has the bimetal snap disc, the spring snap disc and the contact part, is thus held in the derailleur housing in a simple manner so that it cannot be lost, but with some play. This guarantees that the derailleur unit does not accidentally come loose from the derailleur housing, even when the derailleur is stored as bulk goods.

The above task is thus completely solved.

Preferably, the second housing side and the housing peripheral side are each designed as closed housing sides and only the first housing side is designed as a partially open housing side (due to the opening provided thereon).

According to a further embodiment, the derailleur housing has a side wall forming the peripheral side of the housing, the free, upper section of which is bent over and forms the first housing side.

The derailleur can be manufactured very easily in this way by flanging the upper section of the side wall. This bent upper section of the side wall then at least partially surrounds the derailleur unit from the first housing side. However, as already mentioned, the first housing side is partially open, since the bent upper section of the side wall does not cover the entire first housing side, but leaves an opening free on it through which the contact part is accessible from outside the derailleur housing. The opening preferably forms a central part in the middle of the first housing side. A free, circumferential edge of the bent section preferably delimits the opening radially.

According to a further embodiment, the bimetal snap disk is designed to snap from a geometrically stable low-temperature configuration into a geometrically stable high-temperature configuration when a response temperature is exceeded, wherein the bimetal snap disk in its low-temperature configuration is held in place by an inner surface of the bent section and, in its high-temperature configuration, rests on the inner surface of the bent section.

The bent upper section of the side wall, which forms the first housing side of the derailleur housing, not only serves to hold the derailleur unit in the derailleur housing in a captive manner, but also functions as a support on which the bimetal snap disc rests from the inside in its high-temperature configuration. This guarantees that the derailleur and its derailleur housing can be used fully functionally even without a switch housing. The bimetal snap disc can rest on the derailleur housing itself in its high-temperature configuration, so that the contact part, which is connected to the bimetal snap disc, can move within the derailleur housing when the bimetal snap disc snaps. A functional test of the derailleur can therefore be carried out without any problems before the derailleur is installed in the switch.

The two configurations of the bimetal snap disc mentioned refer to different geometric positions of the bimetal snap disc. In the low-temperature configuration or the low-temperature position, the bimetal snap disc is preferably convexly curved on its upper side. In the high-temperature configuration or the high-temperature position, the bimetal snap disc is preferably concavely curved on its upper side.

According to a further embodiment, the derailleur housing is designed as a single piece. It therefore preferably consists of a single piece from which all sides of the housing are integrally formed. This reduces the total number of parts and thus the costs. At the same time, this contributes to a very pressure-stable construction of the derailleur. This is not only advantageous when the derailleur is stored as bulk goods, but also in the final installed state in which the derailleur is installed in the temperature-dependent switch.

According to a further embodiment, the derailleur housing has an electrically conductive material. The derailleur preferably consists of an electrically conductive material. This electrically conductive material is particularly preferably a metal.

This design makes it possible to use the switchgear housing as a current-carrying component of the temperature-dependent switch. In principle, it is also possible to use the switchgear housing itself in the temperature-dependent switch as one of the two electrical contacts. This simplifies the structure of the switch and enables a very simple electrical connection.

According to a further embodiment, the derailleur housing has a dome- or pot-shaped section which forms at least part of the second housing side. This dome- or pot-shaped section preferably forms a centrally arranged part of the second housing side.

The dome or cup-shaped section guarantees the freedom of movement of the derailleur unit located in the derailleur housing. This creates space for the contact part in a simple and space-saving manner when it moves from its low-temperature configuration to its high-temperature configuration within the derailleur housing when the bimetal snap disc snaps over.

According to a further embodiment, the derailleur housing is designed to be rotationally symmetrical about a central axis. This simplifies the installation of the derailleur together with its derailleur housing in a switch housing of the temperature-dependent switch, since the derailleur can be inserted into the temperature-dependent switch in various positions rotated around the central axis. In addition, the rotationally symmetrical design of the derailleur housing enables the force to be distributed evenly in all directions (radial directions).

According to a further embodiment, the bimetal snap-action disc has a first through hole and the spring snap-action disc has a second through hole, wherein the contact part is guided through the first through-hole and the second through-hole, wherein the contact part further comprises a support shoulder protruding radially from the base body, a first locking element which is arranged on a first side of the support shoulder, and a second locking element which is arranged on a second side of the support shoulder opposite the first side. The bimetal snap disk is arranged between the first locking element and the support shoulder and is held captive by the first locking element and the support shoulder but with play on the contact part. The spring snap disk is arranged between the second locking element and the support shoulder and is held captive by the second locking element and the support shoulder but with play on the contact part.

The locking elements can each be one or more retaining claws that protrude radially from the base body of the contact part. Alternatively, the locking elements can each have a flanged collar that extends circumferentially around the base body of the contact part. Both the retaining claws and this bent collar can form individual circumferential sections of the base body or run around the entire circumference of the base body. In this way, the two snap disks are held captive on the base body, but with play.

The locking elements for holding and locking the bimetal snap disk and the spring snap disk are preferably integrally connected to the base body of the contact part, whereby they can be produced by forming a respective part of the base body. The contact part is thus formed in one piece and the base body of the contact part is integrally connected to the support shoulder and the locking elements. Overall, a switching mechanism unit consisting of only three parts can be formed from the contact part, the bimetal snap disk and the spring snap disk, which is implemented as a captive unit.

The three-part design of the derailleur unit has the advantage of requiring as few necessary components as possible as well as the advantage of a mechanically stable and resilient design of the derailleur.

According to a further embodiment, the first through hole is arranged centrally in the bimetal snap-action disk. Likewise, the second through hole is preferably arranged centrally in the spring snap-action disk.

The bimetal snap disk and the spring snap disk are preferably each designed in the shape of a circular disk. Furthermore, the bimetal snap disk and the spring snap disk are preferably each designed to be bistable.

In this respect, "bistable" means that both snap disks each have two different, stable geometric configurations/positions, whereby the two stable configurations/positions of the bimetal snap disk are temperature-dependent and the two stable configurations/positions of the spring snap disk are temperature-independent. This means that the two snap disks remain stable in their respective positions after they have snapped from one configuration to the other, without them snapping back in an undesirable manner. The switching mechanism therefore only snaps back when the response temperature of the bimetal snap disk is exceeded and the return temperature of the bimetal snap disk is undershot. The spring snap disk snaps into its other configuration/position together with the bimetal snap disk.

It is understood that the features mentioned above and those to be explained below can be used not only in the configuration specified in each case, but also in other combinations or on their own, without departing from the scope of the present invention.

Fig. 1

eine schematische Schnittansicht des temperaturabhängigen Schaltwerks gemäß einem ersten Ausführungsbeispiel der vorliegenden Erfindung;

Fig. 2

eine schematische Schnittansicht des temperaturabhängigen Schaltwerks gemäß einem zweiten Ausführungsbeispiel der vorliegenden Erfindung;

Fig. 3

eine schematische Schnittansicht des temperaturabhängigen Schalters gemäß einem Ausführungsbeispiel der vorliegenden Erfindung, wobei sich der Schalter in seiner Tieftemperaturstellung befindet;

Fig. 4

eine schematische Schnittansicht des in Fig. 3 gezeigten temperaturabhängigen Schalters, wobei sich der Schalter in seiner Hochtemperaturstellung befindet; und

Fig. 5

eine schematische Schnittansicht eines weiteren Ausführungsbeispiels des temperaturabhängigen Schalters, wobei sich der Schalter in seiner Tieftemperaturstellung befindet.

Embodiments of the invention are shown in the drawings and are explained in more detail in the following description. They show:

Fig. 1

a schematic sectional view of the temperature-dependent switching mechanism according to a first embodiment of the present invention;

Fig. 2

a schematic sectional view of the temperature-dependent switching mechanism according to a second embodiment of the present invention;

Fig. 3

a schematic sectional view of the temperature-dependent switch according to an embodiment of the present invention, wherein the switch is in its low-temperature position;

Fig. 4

a schematic sectional view of the Fig. 3 temperature-dependent switch shown, with the switch in its high temperature position; and

Fig. 5

a schematic sectional view of another embodiment of the temperature-dependent switch, wherein the switch is in its low-temperature position.

Fig. 1-2 show two different embodiments of the switching mechanism according to the invention, each in a schematic sectional view. The switching mechanism is designated in its entirety with the reference number 10.

The derailleur 10 is a temperature-dependent derailleur. It has a functional derailleur unit 12 and a derailleur housing 14 surrounding this derailleur unit 12. The derailleur housing 14 surrounds the derailleur unit 12 from all six spatial directions, at least partially in each case. As explained in detail below, the derailleur housing 14 is, however, designed as a partially open housing, so that the derailleur unit 12 is accessible from at least one spatial direction, preferably from only one spatial direction, from outside the derailleur housing 14.

Due to the fact that the derailleur housing 14 at least partially surrounds the derailleur unit 12 from all six spatial directions, the derailleur unit 12 is held captive in the derailleur housing 14. As long as the derailleur 10 is not inserted into a temperature-dependent switch, there is preferably a certain Play between the derailleur unit 12 and the derailleur housing 14. The derailleur unit 12 is movable within the derailleur housing 14 in the low temperature position of the derailleur 10.

The switching unit 12 is constructed in three parts. The switching unit 12 has a temperature-dependent bimetal snap disk 16, a temperature-independent spring snap disk 18 and a contact part 20. The bimetal snap disk 16 and the spring snap disk 18 are held captive on the contact part 20.

The derailleur unit 12 can thus be pre-produced as a semi-finished product and then inserted as a whole into the derailleur housing 14. The derailleur 10 together with the derailleur unit 12 and the derailleur housing 14 then also form a semi-finished product for a temperature-dependent switch that is later produced from it.

Since the three components 16, 18, 20 of the switching unit 12 are captively connected to one another and the switching unit 12 is held captively in the switching housing 14, the switching unit 10 can be kept in stock as bulk material until it is installed in a temperature-dependent switch.

The switchgear housing 14 protects the fragile components of the switchgear unit 12, in particular the bimetal snap disk 16 and the spring snap disk 18, from damage during bulk storage. The introduction of the switchgear unit 12 into such a switchgear housing 14 also has the advantage that the switchgear 10 can be very easily inserted into a temperature-dependent switch to be manufactured. Due to this very simple handling of the switchgear, the assembly process of the temperature-dependent switch can be easily automated.

The derailleur housing 14 surrounds the derailleur unit 12 from a first housing side 22, a second housing side 24 opposite the first housing side 22 and a housing peripheral side 26 running between and transverse to the first and second housing sides 22, 24, each at least partially. Preferably, the Derailleur housing 14 completely surrounds the derailleur unit 12 both from the second housing side 24 and from the housing peripheral side 26. The second housing side 24 and the housing peripheral side 26 therefore preferably form closed housing sides of the derailleur housing 14. Only the first housing side 22 is a partially open housing side of the derailleur housing 14. In other words, the housing peripheral side 26 surrounds the derailleur unit 12 along the entire circumference, i.e. from a total of four spatial directions that are orthogonal to one another. Furthermore, the derailleur housing 14 also completely surrounds the derailleur unit 12 from a further spatial direction, namely from a spatial direction that is orthogonal to the second housing side 24. Only from the sixth spatial direction, which is orthogonal to the first housing side 22, does the derailleur housing 14 only partially surround the derailleur unit 12.

On the first housing side 22, the derailleur housing 14 has an opening 28 through which the contact part 20 is accessible from outside the derailleur housing 14.

According to the two Fig. 1 and 2 In the embodiments of the derailleur 10 shown, the contact part 20 protrudes permanently through the opening 28 to the outside. However, depending on the design of the height of the derailleur housing 13, this does not necessarily have to be the case. In principle, it is sufficient if the contact part 20 is accessible from the outside through the opening 28 and the derailleur unit 12 is movable within the derailleur housing 14 in such a way that the contact part 20 protrudes through the opening 28 to the outside with a corresponding movement within the derailleur housing.

A diameter D ₁ of the opening 28 is smaller than a diameter D ₂ of the bimetallic snap disk 16 and/or the spring snap disk 18 measured parallel thereto. Thus, although the contact part 20 is accessible from the outside through the opening 28, the bimetallic snap disk 16 and the spring snap disk 18 cannot become detached from the derailleur housing 14.

The derailleur housing 14 is designed in one piece and consists of an electrically conductive material, for example metal. It has a bottom wall 30 and a the bottom wall has a side wall 32 integrally connected to it. The bottom wall 30 forms the second housing side 24 of the derailleur housing 14. The side wall 32 forms the peripheral side 26 of the derailleur housing 14. A free upper section 34 of the side wall 32 is bent in the direction of a central axis 36, which forms the longitudinal axis of the contact part 20. A free, peripheral edge 38 of this bent upper section 34 delimits the opening 28 of the derailleur housing 14 in the radial direction.

In the Fig. 1 and 2 In the low temperature position of the switching mechanism 10 shown, the spring snap disk 18 rests with its outer edge on the switching mechanism housing 14. More precisely, the spring snap disk 18 rests with its outer edge on an inner side 40 of the base wall 30 facing the switching mechanism unit 12. In this position of the switching mechanism 10, the spring snap disk 18 carries the contact part 20. In this switching mechanism position, however, the bimetal snap disk 16 is mounted in the switching mechanism housing 14 with more or less no force.

The two snap disks 16, 18 are preferably designed in the shape of a circular disk and each have a centrally arranged through hole 42, 44. The through hole 42 arranged centrally in the bimetal snap disk 16 is referred to here as the first through hole. The through hole 44 arranged in the spring snap disk 18 is referred to as the second through hole.

The two snap disks 16, 18 are placed over the contact part 20 from opposite sides with their respective through holes 42, 44. The contact part 20 thus penetrates both snap disks 16, 18 at a central point.

The contact part 20 has a base body 46, which is preferably solid and made of an electrically conductive material. The base body 46 is guided through the two through holes 42, 44.

Approximately in the middle, i.e. approximately halfway up, the contact part 20 has a support shoulder 48 which projects radially from the base body 46. The two snap disks 16, 18 from opposite sides. The bimetal snap disk 16 is arranged on a first side of the support shoulder 48, which in Fig. 1 and 2 forms the top of the support shoulder 48. The spring snap disk 18 is arranged on a second side of the support shoulder 48 opposite the first side, which in Fig. 1 and 2 which forms the underside of the support shoulder 48.

Furthermore, locking elements 50, 52 are formed on the contact part 20, with the aid of which the two snap disks 16, 18 are held on the contact part 20. The two locking elements 50, 52 protrude radially from the base body 46 of the contact part 20. The first locking element 50 is arranged on the first side of the support shoulder 48. The second locking element 52 is arranged on the opposite second side of the support shoulder 48.

The bimetallic snap disk 16 is arranged between the first locking element 50 and the support shoulder 48 and is held captive on the contact part 20 due to the radial projection of the first locking element 50 and the support shoulder 48 between the first locking element 50 and the support shoulder 48.

The spring snap disk 18 is arranged between the second locking element 52 and the support shoulder 48 and is held captive on the contact part 20 due to the radial projection of the second locking element 52 and the support shoulder 48 between the second locking element 52 and the support shoulder 48.

The contact part 20 is formed in one piece together with the support shoulder 48 and the two locking elements 50, 52. The support shoulder 48 as well as the two locking elements 50, 52 are thus formed integrally with the base body 46 of the contact part 20.

In the Fig. 1 and 2 In the embodiments shown, the two locking elements 50, 52 are each designed as a circumferentially encircling collar. The circumferentially encircling collar forming the first locking element 50 protrudes radially upwards from the base body 46 of the contact part 20. The second The collar forming the locking element 52 projects radially downwards from the base body 46 of the contact part 20.

Both collars can be formed relatively easily by forming a circumferential cut notch in the contact part 20. The cut notches are formed in the contact part after the two snap disks 16, 18 with their through holes 40, 42 have been slipped over the contact part 20.

As an alternative to such collars which are produced by introducing cut notches, the two locking elements 50, 52 can also each have one or more retaining claws (not shown). Such retaining claws are also preferably designed integrally with the base body 46 of the contact part 20.

For the function of the switching mechanism 10, it is advantageous if the bimetal snap disk 16 is held on the contact part 20 with greater play than the spring snap disk 18. This guarantees sufficient free movement of the bimetal snap disk 16. At the same time, the slightly smaller play between the spring snap disk 18 and the contact part 20 enables the best possible electrical contact between these two components.

The two in Fig. 1 and 2 The embodiments of the derailleur 10 shown in FIG. 1 differ essentially in the shape of the derailleur housing 14. In the Fig. 1 In the embodiment shown, the bottom wall 30, which forms the second housing side 24 of the derailleur housing 14, is essentially plate-shaped and has a pot-like bulge 54 in a central section. In the embodiment shown in Fig. 2 In the embodiment shown, however, the bottom wall 30 is designed in an arc shape in section. The bottom wall 30 of the derailleur housing 14 thus forms a type of convex dome.

Of course, other shapes of the switch housing 14 are possible. However, it is important that the contact part 20 deviates from the position shown in Fig. 1 and 2 shown low temperature position to the high temperature position can move downwards within the derailleur housing 14. For this purpose, there must be sufficient space, in particular for the contact part 20, so that it does not collide with the base wall 30 in the high-temperature position of the derailleur 10.

In Fig. 3 and 4 an embodiment of a temperature-dependent switch in which the switching mechanism 10 according to the invention can be used is shown in a schematic sectional view. The switch is identified in its entirety with the reference number 100.

Fig. 3 shows the low temperature position of switch 100. Fig. 4 shows the high temperature position of switch 100.

The switch 100 has according to the Fig. 3 and 4 The embodiment shown has a switch housing 56 which acts as a housing for the rear derailleur 10. The rear derailleur 10 is inserted into the switch housing 56 together with its rear derailleur housing 14. The rear derailleur 10 corresponds to the Fig. 1 embodiment shown.

The switch housing 56 comprises a pot-like lower part 58 and a cover part 60 which is held to the lower part 58 by a bent or flanged edge 62.

Both the lower part 58 and the cover part 60 are in the Fig. 3 and 4 In the embodiment shown, the housing is made of an electrically conductive material, preferably metal. An insulating film 64 is arranged between the lower part 58 and the cover part 60. The insulating film 64 ensures electrical insulation of the lower part 58 from the cover part 60. The insulating film 64 also ensures a mechanical seal that prevents liquids or contaminants from entering the housing interior from the outside.

Since the base part 58 and the cover part 60 are each made of electrically conductive material, thermal contact with an electrical device to be protected can be established via their outer surfaces. The outer surfaces also serve to external electrical connection of the switch 100. For example, the outer surface 61 of the cover part 60 can function as the first electrical connection and the outer side 59 of the base part 58 can function as the second electrical connection.

On the outside of the cover part 60, as shown in Fig. 3 and 4 shown, a further insulation layer 66 may be arranged.

The derailleur 10 is clamped between the lower part 58 and the cover part 60. A spacer ring 68, against which the derailleur housing 14 rests on the circumference, serves to position the derailleur 10. It is particularly important that the contact part 20 is aligned with a counter contact 70, which is arranged on the inside of the cover part 60. This counter contact 70 is also referred to here as the first stationary contact. The inside 71 of the lower part 58 serves as the second stationary contact.

In the Fig. 3 In the low-temperature position of the switch 100 shown, the temperature-independent spring snap disk 18 is in its first configuration and the temperature-dependent bimetallic snap disk 16 is in its low-temperature configuration. The spring snap disk 18 presses the contact part 20 against the counter contact 70. The switch 100 is thus in its closed position, in which an electrically conductive connection is established between the first stationary contact 70 and the second stationary contact 71 via the contact part 20 and the spring snap disk 18. The contact pressure between the contact part 20 and the first stationary contact 70 is generated by the spring snap disk 18. In this state, the bimetallic snap disk 16 is mounted in the switchgear housing 14 with almost no force.

If the temperature of the device to be protected and thus the temperature of the switch 100 and the bimetal snap-action disk 16 arranged therein increases to the switching temperature of the bimetal snap-action disk 16 or beyond the switching temperature, the bimetal snap-action disk 16 snaps from its Fig. 3 shown, convex low-temperature position to its concave high-temperature position, which is Fig. 4 As shown, the bimetal snap disk 16 rests with its outer Edge on the first housing side 22 of the derailleur housing 14. More precisely, the bimetal snap disk 16 is supported on an inner surface 72 of the bent upper section 34 arranged inside the derailleur housing 14. As a result, the spring snap disk 18 bends downwards at the same time at its center, so that the spring snap disk 18 is released from its Fig. 3 shown, first stable geometric configuration into its Fig. 4 shown, second geometrically stable configuration snaps over.

Fig. 4 shows the high temperature position of switch 100, in which it is open. The circuit is thus interrupted.

When the device to be protected and thus the switch 100 together with the bimetal snap disk 16 cool down again, the bimetal snap disk 16 snaps back into its low temperature position when the switch-back temperature, which is also referred to as the return temperature, is reached, as is the case, for example, in Fig. 3 This allows a reversible switching behavior to be realized.

It is of course also possible for the switch 100 to be prevented from switching back once it has snapped into the high-temperature position by means of a corresponding locking device. Such locking devices, which are used in particular in one-time switches where switching back is to be prevented, are already known in large numbers from the prior art.

Fig. 5 shows a further embodiment of the switch 100 according to the invention. The switch housing 56 is in comparison to the one in Fig. 3 and 4 The switch housing 56 shown here is designed to be much simpler. It has only one contact 70, which is connected to a first electrical connection 61, and a second contact 71, which is connected to a second connection 59. The two contacts 70, 71 are designed as simple metal sheets that are connected to one another via an insulator 76. The insulator 76 electrically separates the two contacts 70, 71 from one another and at the same time provides a mechanical connection between the two contacts 70, 71.

The rear derailleur 10 is in the Fig. 5 In the embodiment shown, the switch housing 56 is only inserted between the two contacts 70, 71. However, the switch housing 56 is partially open here and, unlike in the Fig. 3 and 4 shown embodiment, not hermetically sealed.

The switch housing 56 of the switch 100 according to the Fig. 5 The embodiment shown can, for example, be integrated directly into a device to be monitored by the switch 100. The simple structure of the Fig. 5 The switch housing 56 shown is intended to illustrate in principle that the switching mechanism 10 according to the invention can also be integrated into much simpler switch housings 56 due to its structural design. The reason for this is in particular that the switching mechanism 10 is already fully functional in itself due to the switching mechanism housing 14 in which the switching mechanism unit 12 is captively mounted. If no hermetic sealing of the switch 100 is required for certain applications, only two contacts 70, 71 are required on the switch housing 56, between which the switching mechanism 10 is clamped. Other components are not necessary on the switch housing 56, apart from the electrical connections 59, 61 connected to the contacts 70, 71.

It is understood that the switching mechanism 10 according to the invention can be used in switch housings of completely different designs.

1. 1. Temperaturabhängiges Schaltwerk 10 für einen temperaturabhängigen Schalter 100, mit:
   • einer temperaturabhängigen Bimetall-Schnappscheibe 16;
   • einer temperaturunabhängigen Feder-Schnappscheibe 18;
   • einem elektrisch leitfähigen Kontaktteil 20, an dem die Bimetall-Schnappscheibe 16 und die Feder-Schnappscheibe 18 unverlierbar gehalten sind, so dass die Bimetall-Schnappscheibe 16, die Feder-Schnappscheibe 18 und das Kontaktteil 20 eine unverlierbar zusammengehaltene Schaltwerkseinheit 12 bilden; und
   • einem Schaltwerksgehäuse 14, in dem die Schaltwerkseinheit 12 angeordnet ist und das die Schaltwerkseinheit 12 unverlierbar hält;
   • wobei das Schaltwerksgehäuse 14 die Schaltwerkseinheit 12 von einer ersten Gehäuseseite 22, einer der ersten Gehäuseseite 22 gegenüberliegenden zweiten Gehäuseseite 24 und einer zwischen und quer zu der ersten und der zweiten Gehäuseseite 22, 24 verlaufenden Gehäuseumfangsseite 26 umgibt, und
   • wobei das Schaltwerksgehäuse 14 als zumindest teilweise offenes Gehäuse ausgestaltet ist und auf der ersten Gehäuseseite 22 eine Öffnung 28 aufweist, durch die das Kontaktteil 20 von außerhalb des Schaltwerksgehäuses 14 zugänglich ist.
2. 2. Temperaturabhängiges Schaltwerk gemäß Ausführungsform 1, wobei das Kontaktteil 20 dauerhaft durch die Öffnung 28 nach außen hindurchragt oder gemeinsam mit der Bimetall-Schnappscheibe 16 und der Feder-Schnappscheibe 18 innerhalb des Schaltwerksgehäuses 14 derart beweglich ist, dass das Kontaktteil 20 bei entsprechender Bewegung innerhalb des Schaltwerksgehäuses 14 durch die Öffnung 28 nach außen hindurchragt.
3. 3. Temperaturabhängiges Schaltwerk gemäß Ausführungsform 1 oder 2, wobei ein Durchmesser D₁ der Öffnung 28 kleiner als ein parallel dazu gemessener Durchmesser D₂ der Bimetall-Schnappscheibe 16 und/oder kleiner als ein parallel dazu gemessener Durchmesser D₂ der Feder-Schnappscheibe 18 ist.
4. 4. Temperaturabhängiges Schaltwerk gemäß einer der vorstehenden Ausführungsformen, wobei das Schaltwerksgehäuses 14 eine die Gehäuseumfangsseite 26 bildende Seitenwand 32 aufweist, deren freier, oberer Abschnitt 34 umgebogen ist und die erste Gehäuseseite 22 bildet.
5. 5. Temperaturabhängiges Schaltwerk gemäß Ausführungsform 4, wobei die Bimetall-Schnappscheibe 16 dazu eingerichtet ist, bei Überschreiten einer Ansprechtemperatur von einer geometrisch stabilen Tieftemperaturkonfiguration in eine geometrisch stabile Hochtemperaturkonfiguration umzuschnappen, und wobei die Bimetall-Schnappscheibe 16 in ihrer Tieftemperaturkonfiguration von einer im Inneren des Schaltwerksgehäuses 14 angeordneten Innenfläche 72 des umgebogenen Abschnitts 34 beabstandet ist und sich in ihrer Hochtemperaturkonfiguration an der Innenfläche 72 des umgebogenen Abschnitts 34 abstützt.
6. 6. Temperaturabhängiges Schaltwerk gemäß einer der vorstehenden Ausführungsformen, wobei das Schaltwerksgehäuse 14 einstückig ausgestaltet ist
7. 7. Temperaturabhängiges Schaltwerk gemäß einer der vorstehenden Ausführungsformen, wobei das Schaltwerksgehäuse 14 ein elektrisch leitfähiges Material aufweist.
8. 8. Temperaturabhängiges Schaltwerk gemäß einer der vorstehenden Ausführungsformen, wobei das Schaltwerksgehäuse 14 einen kuppel- oder topfförmigen Abschnitt 54 aufweist, der zumindest einen Teil der zweiten Gehäuseseite 24 bildet.
9. 9. Temperaturabhängiges Schaltwerk gemäß einer der vorstehenden Ausführungsformen, wobei das Schaltwerksgehäuse 14 rotationssymmetrisch um eine zentrale Achse 36 ausgestaltet ist.
10. 10. Temperaturabhängiges Schaltwerk gemäß Ausführungsform 8 und 9, wobei der kuppel- oder topfförmige Abschnitt 54 einen zentral angeordneten Teil der zweiten Gehäuseseite 24 bildet und rotationssymmetrisch um die zentrale Achse 36 ausgestaltet ist.
11. 11. Temperaturabhängiges Schaltwerk gemäß Ausführungsform 9 oder 10, wobei das Schaltwerk 10 rotationssymmetrisch um die zentrale Achse 36 ausgestaltet ist.
12. 12. Temperaturabhängiges Schaltwerk gemäß einer der vorstehenden Ausführungsformen, wobei die Bimetall-Schnappscheibe 16 ein erstes Durchgangsloch 42 und die Feder-Schnappscheibe 18 ein zweites Durchgangsloch 44 aufweist, wobei das Kontaktteil 20 durch das erste Durchgangsloch 42 und das zweite Durchgangsloch 44 hindurchgeführt ist, wobei das Kontaktteil 20 ferner eine radial abstehende Auflageschulter 48, ein erstes Arretierelement 50, das auf einer ersten Seite der Auflageschulter 48 angeordnet ist, und ein zweites Arretierelement 52, das auf einer der ersten Seite gegenüberliegenden zweiten Seite der Auflageschulter 48 angeordnet ist, aufweist, wobei die Bimetall-Schnappscheibe 16 zwischen dem ersten Arretierelement 50 und der Auflageschulter 48 angeordnet ist und von dem ersten Arretierelement 50 und der Auflageschulter 48 unverlierbar an dem Kontaktteil 20 gehalten ist, und wobei die Feder-Schnappscheibe 18 zwischen dem zweiten Arretierelement 52 und der Auflageschulter 48 angeordnet ist und von dem zweiten Arretierelement 52 und der Auflageschulter 48 unverlierbar an dem Kontaktteil 20 gehalten ist.
13. 13. Temperaturabhängiges Schaltwerk gemäß Ausführungsform 12, wobei das erste Durchgangsloch 42 zentral in der Bimetall-Schnappscheibe 16 angeordnet ist, und wobei das zweite Durchgangsloch 44 zentral in der Feder-Schnappscheibe 18 angeordnet ist.
14. 14. Temperaturabhängiges Schaltwerk gemäß einer der vorstehenden Ausführungsformen, wobei die Bimetall-Schnappscheibe 16 und die Feder-Schnappscheibe 18 jeweils kreisscheibenförmig ausgestaltet sind.
15. 15. Temperaturabhängiger Schalter 100 mit einem temperaturabhängigen Schaltwerk 10 gemäß einer der Ausführungsformen 1-14 und einem das Schaltwerk 10 umgebenden Schaltergehäuse 56, das einen ersten Kontakt 70 und einen zweiten Kontakt 71 aufweist, wobei das Schaltwerk 10 dazu eingerichtet ist, unterhalb einer Ansprechtemperatur der Bimetall-Schnappscheibe 16 eine elektrische Verbindung zwischen dem ersten und dem zweiten Kontakt 70, 71 herzustellen und bei Überschreiten der Ansprechtemperatur die elektrische Verbindung zu unterbrechen.

The following is a list of other embodiments:

1. 1. Temperature-dependent switching mechanism 10 for a temperature-dependent switch 100, with:
   • a temperature-dependent bimetal snap disk 16;
   • a temperature-independent spring snap disk 18;
   • an electrically conductive contact part 20, on which the bimetal snap-action disk 16 and the spring snap-action disk 18 are held captively, so that the bimetal snap-action disk 16, the spring snap-action disk 18 and the contact part 20 form a captively held together switching unit 12; and
   • a derailleur housing 14 in which the derailleur unit 12 is arranged and which holds the derailleur unit 12 captive;
   • wherein the derailleur housing 14 surrounds the derailleur unit 12 by a first housing side 22, a second housing side 24 opposite the first housing side 22 and a housing peripheral side 26 extending between and transverse to the first and second housing sides 22, 24, and
   • wherein the derailleur housing 14 is designed as an at least partially open housing and has an opening 28 on the first housing side 22 through which the contact part 20 is accessible from outside the derailleur housing 14.
2. 2. Temperature-dependent switching mechanism according to embodiment 1, wherein the contact part 20 permanently projects outwards through the opening 28 or is movable together with the bimetallic snap disk 16 and the spring snap disk 18 within the switching mechanism housing 14 in such a way that the contact part 20 projects outwards through the opening 28 upon corresponding movement within the switching mechanism housing 14.
3. 3. Temperature-dependent switching mechanism according to embodiment 1 or 2, wherein a diameter D ₁ of the opening 28 is smaller than a diameter D ₂ of the bimetallic snap disk 16 measured parallel thereto and/or smaller than a diameter D ₂ of the spring snap disk 18 measured parallel thereto.
4. 4. Temperature-dependent rear derailleur according to one of the preceding embodiments, wherein the rear derailleur housing 14 has a side wall 32 forming the housing peripheral side 26, the free, upper section 34 of which is bent over and forms the first housing side 22.
5. 5. Temperature-dependent switching mechanism according to embodiment 4, wherein the bimetallic snap disk 16 is designed to Response temperature from a geometrically stable low-temperature configuration to a geometrically stable high-temperature configuration, and wherein the bimetallic snap disk 16 in its low-temperature configuration is spaced from an inner surface 72 of the bent portion 34 arranged in the interior of the switchgear housing 14 and is supported on the inner surface 72 of the bent portion 34 in its high-temperature configuration.
6. 6. Temperature-dependent derailleur according to one of the preceding embodiments, wherein the derailleur housing 14 is designed in one piece
7. 7. Temperature-dependent rear derailleur according to one of the preceding embodiments, wherein the rear derailleur housing 14 comprises an electrically conductive material.
8. 8. Temperature-dependent rear derailleur according to one of the preceding embodiments, wherein the rear derailleur housing 14 has a dome- or pot-shaped portion 54 which forms at least part of the second housing side 24.
9. 9. Temperature-dependent rear derailleur according to one of the preceding embodiments, wherein the rear derailleur housing 14 is designed to be rotationally symmetrical about a central axis 36.
10. 10. Temperature-dependent switching mechanism according to embodiments 8 and 9, wherein the dome- or pot-shaped section 54 forms a centrally arranged part of the second housing side 24 and is designed rotationally symmetrical about the central axis 36.
11. 11. Temperature-dependent switching mechanism according to embodiment 9 or 10, wherein the switching mechanism 10 is designed to be rotationally symmetrical about the central axis 36.
12. 12. Temperature-dependent switching mechanism according to one of the preceding embodiments, wherein the bimetallic snap disk 16 has a first through hole 42 and the spring snap disk 18 has a second through hole 44, wherein the contact part 20 is guided through the first through hole 42 and the second through hole 44, wherein the contact part 20 further has a radially projecting support shoulder 48, a first locking element 50 which is arranged on a first side of the support shoulder 48, and a second locking element 52 which is arranged on a second side of the support shoulder 48 opposite the first side, wherein the bimetal snap disk 16 is arranged between the first locking element 50 and the support shoulder 48 and is held captive on the contact part 20 by the first locking element 50 and the support shoulder 48, and wherein the spring snap disk 18 is arranged between the second locking element 52 and the support shoulder 48 and is held by the second locking element 52 and the support shoulder 48 is held captive on the contact part 20.
13. 13. Temperature-dependent switching mechanism according to embodiment 12, wherein the first through hole 42 is arranged centrally in the bimetallic snap disk 16, and wherein the second through hole 44 is arranged centrally in the spring snap disk 18.
14. 14. Temperature-dependent switching mechanism according to one of the preceding embodiments, wherein the bimetallic snap disk 16 and the spring snap disk 18 are each designed in the shape of a circular disk.
15. 15. Temperature-dependent switch 100 with a temperature-dependent switching mechanism 10 according to one of the embodiments 1-14 and a switch housing 56 surrounding the switching mechanism 10, which has a first contact 70 and a second contact 71, wherein the switching mechanism 10 is designed to establish an electrical connection between the first and the second contact 70, 71 below a response temperature of the bimetallic snap disk 16 and to interrupt the electrical connection when the response temperature is exceeded.

Claims (13)

Temperature-dependent switching mechanism (10) for a temperature-dependent switch (100), with: - a temperature-dependent bimetallic snap-action disc (16); - a temperature-independent spring snap disc (18); - an electrically conductive contact part (20) on which the bimetallic snap-action disk (16) and the spring snap-action disk (18) are held captively, so that the bimetallic snap-action disk (16), the spring snap-action disk (18) and the contact part (20) form a switching mechanism unit (12) held together captively; and - a derailleur housing (14) in which the derailleur unit (12) is arranged and which holds the derailleur unit (12) captive; wherein the derailleur housing (14) surrounds the derailleur unit (12) from a first housing side (22), a second housing side (24) opposite the first housing side (22) and a housing peripheral side (26) running between and transversely to the first and second housing sides (22, 24), and wherein the derailleur housing (14) is designed as an at least partially open housing and has an opening (28) on the first housing side (22) through which the contact part (20) is accessible from outside the derailleur housing (14), wherein the contact part (20) permanently projects outwards through the opening (28) or is movable together with the bimetallic snap disk (16) and the spring snap disk (18) within the switching mechanism housing (14) in such a way that the contact part (20) projects outwards through the opening (28) upon corresponding movement within the switching mechanism housing (14), and wherein a diameter (D ₁ ) of the opening (28) is smaller than a diameter (D ₂ ) of the bimetallic snap disk (16) measured parallel thereto and smaller than a diameter (D ₂ ) of the spring snap disk (18) measured parallel thereto. Temperature-dependent switching mechanism according to one of the preceding claims, wherein the switching mechanism housing (14) has a side wall (32) forming the housing peripheral side (26), the free, upper section (34) of which is bent over and forms the first housing side (22). Temperature-dependent switching mechanism according to claim 2, wherein the bimetallic snap disk (16) is designed to snap from a geometrically stable low-temperature configuration into a geometrically stable high-temperature configuration when a response temperature is exceeded, and wherein the bimetallic snap disk (16) in its low-temperature configuration is spaced from an inner surface (72) of the bent section (34) arranged in the interior of the switching mechanism housing (14) and in its high-temperature configuration is supported on the inner surface (72) of the bent section (34). Temperature-dependent switching mechanism according to one of the preceding claims, wherein the switching mechanism housing (14) is designed in one piece Temperature-dependent switching mechanism according to one of the preceding claims, wherein the switching mechanism housing (14) comprises an electrically conductive material. Temperature-dependent switching mechanism according to one of the preceding claims, wherein the switching mechanism housing (14) has a dome- or pot-shaped portion (54) which forms at least part of the second housing side (24). Temperature-dependent switching mechanism according to one of the preceding claims, wherein the switching mechanism housing (14) is designed to be rotationally symmetrical about a central axis (36). Temperature-dependent switching mechanism according to claims 6 and 7, wherein the dome- or pot-shaped section (54) forms a centrally arranged part of the second housing side (24) and is designed to be rotationally symmetrical about the central axis (36). Temperature-dependent switching mechanism according to claim 7 or 8, wherein the switching mechanism (10) is designed to be rotationally symmetrical about the central axis (36). Temperature-dependent switching mechanism according to one of the preceding claims, wherein the bimetallic snap disk (16) has a first through hole (42) and the spring snap disk (18) has a second through hole (44), wherein the contact part (20) is guided through the first through hole (42) and the second through hole (44), wherein the contact part (20) further has a radially projecting support shoulder (48), a first locking element (50) which is arranged on a first side of the support shoulder (48), and a second locking element (52) which is arranged on a second side of the support shoulder (48) opposite the first side, wherein the bimetallic snap disk (16) is arranged between the first locking element (50) and the support shoulder (48) and is held captive on the contact part (20) by the first locking element (50) and the support shoulder (48), and wherein the spring snap disk (18) is arranged between the second locking element (52) and the support shoulder (48) and is held captive on the contact part (20) by the second locking element (52) and the support shoulder (48). Temperature-dependent switching mechanism according to claim 10, wherein the first through hole (42) is arranged centrally in the bimetallic snap disk (16), and wherein the second through hole (44) is arranged centrally in the spring snap disk (18). Temperature-dependent switching mechanism according to one of the preceding claims, wherein the bimetallic snap disk (16) and the spring snap disk (18) are each designed in the shape of a circular disk. Temperature-dependent switch (100) with a temperature-dependent switching mechanism (10) according to one of claims 1-12 and a switch housing (56) surrounding the switching mechanism (10) which has a first contact (70) and a second contact (71), wherein the switching mechanism (10) is designed to be below to establish an electrical connection between the first and the second contact (70, 71) at a response temperature of the bimetallic snap disk (16) and to interrupt the electrical connection when the response temperature is exceeded.

Images