EP4325543A1 - Temperature-dependent switch - Google Patents

Abstract

Temperature-dependent switch (100), comprising a temperature-dependent switching mechanism (10) with a switching mechanism unit (14) and a switching mechanism housing (16), in which the switching mechanism unit (14) is arranged and captively held therein. The switch (100) further comprises a switch housing (12) in which the switching mechanism housing (16) is arranged and held captively therein. The rear derailleur housing (16) surrounds the rear derailleur unit (14) from a first housing side (24), a second housing side (26) opposite the first housing side (24) and a second housing side (26) extending between and transversely to the first and second housing sides (24, 26). Circumferential side of the housing (28) and has an opening (30) on the first side of the housing (24), through which a movable contact part (22) of the switching mechanism (10) interacts with a stationary contact part (32) arranged on the switch housing (12). The switching mechanism housing (16) has an electrically conductive base body (36) which forms at least part of the second housing side (26), this part of the second housing side (26) forming a freely accessible outside (62) of the switch (100). The switch (100) further comprises an insulator (38), which electrically insulates the base body (36) of the switching mechanism housing (16) from the switch housing (12) and is arranged inside the switch housing (12).

Description

The present invention relates to a temperature-dependent switch.

A variety of temperature-dependent switches are generally already known. An exemplary temperature-dependent switch is in the DE 10 2011 119 632 B3 disclosed.

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

The one from the DE 10 2011 119 632 B3 Known switch has a switch housing, in the interior of which a switching mechanism is arranged in a hermetically sealed manner. 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 rear derailleur is arranged clamped between the cover part and the lower part. When the switch is manufactured, the rear derailleur is initially inserted loosely into the lower part. The insulating film is then placed over the lower part and the lid part is placed on top and firmly connected to the lower part.

The temperature-dependent switching mechanism arranged in the switch housing has a spring snap-action disk, to which a movable contact part is attached, and a bimetal snap-action disk placed over the movable contact part. The spring snap disk presses the movable contact part against a stationary counter-contact, which is arranged on the inside of the switch housing on the cover part. With its outer edge, the spring snap disk is supported in the lower part of the switch housing, so that the electrical current flows from the lower part through the spring snap disk and the movable contact part into the stationary mating contact and from there into the cover part.

The temperature-dependent bimetal snap-action disk 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 made of metals or metal alloys in such bimetal snap disks is usually cohesive or positive and is achieved, for example, by rolling.

Such a bimetal snap-action disk has a first stable geometric shape at low temperatures, below the response temperature of the bimetal snap-action disk Configuration (low temperature configuration) and at high temperatures, above the response temperature of the bimetal snap disk, a second stable geometric configuration (high temperature configuration). Depending on the temperature, the bimetal snap-action disk switches from its low-temperature configuration to its high-temperature configuration in the manner of hysteresis. This process is often referred to as "snapping", which is also why it is called a "snapping disk".

If the temperature of the bimetal snap-action disk rises above the response temperature of the bimetal snap-action disk as a result of a temperature increase in the device to be protected, it snaps from its low-temperature configuration to its high-temperature configuration. As a result, the movable contact part is lifted off the stationary mating contact, so that the switch opens and the device to be protected is switched off and can no longer heat up.

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

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

With the one from the DE 10 2011 119 632 B3 In the known switch, the bimetal snap-action disk is already connected in advance (outside the switch housing) to the contact part attached to the spring snap-action disk. For this purpose, the bimetal snap disk is placed 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-action disk attached to the contact part, but the bimetal snap-action disk is also held captively on it.

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

The spring snap washer is from the DE 10 2011 119 632 B3 known switch welded or soldered to the contact part in order to produce the best possible electrical contact between these two components. However, it has been shown that the welded or soldered connection between the contact part and the spring snap-action disk can break, particularly when storing bulk goods for the switching mechanism pre-produced as a semi-finished product. Of course, such defective switches can no longer be used. The problem, however, is that defects in the rear derailleur can often only be identified after the entire switch has been assembled, since a functional test of the rear derailleur is only possible when the switch is fully assembled.

It is therefore an object of the present invention to provide a temperature-dependent switch whose switching mechanism can be pre-produced as a semi-finished product without being susceptible to damage, and with which a functional test of the switching mechanism is possible before its final installation in the switch. Furthermore, the switch should be comparatively easy to install, have a low overall height and be designed to be comparatively pressure-stable.

• ein temperaturabhängiges Schaltwerk mit einer Schaltwerkseinheit, die ein mit einer Bimetall-Schnappscheibe gekoppeltes, bewegliches Kontaktteil aufweist, und mit einem Schaltwerksgehäuse, in dem die Schaltwerkseinheit angeordnet und darin unverlierbar gehalten ist; und
• ein Schaltergehäuse, in dem das Schaltwerksgehäuse angeordnet und darin unverlierbar gehalten ist, wobei das Schaltergehäuse ein stationäres Kontaktteil aufweist, das als Gegenkontakt zu dem beweglichen Kontaktteil fungiert;

• 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 umgibt und auf der ersten Gehäuseseite eine Öffnung aufweist, durch die das bewegliche Kontaktteil vorzugsweise direkt mit dem stationären Kontaktteil zusammenwirkt,
• wobei das Schaltwerksgehäuse einen elektrisch leitfähigen Grundkörper aufweist, der zumindest einen Teil der zweiten Gehäuseseite bildet, wobei dieser Teil der zweiten Gehäuseseite eine frei zugängliche Außenseite des Schalters bildet, und
• wobei der Schalter ferner einen Isolator aufweist, der den Grundkörper des Schaltwerksgehäuses gegenüber dem Schaltergehäuse elektrisch isoliert und im Inneren des Schaltergehäuses angeordnet ist.

This object is achieved according to the invention by a temperature-dependent switch, which comprises the following components:

• a temperature-dependent switching mechanism with a switching mechanism unit which has a movable contact part coupled to a bimetal snap-action disk, and with a switching mechanism housing in which the switching mechanism unit is arranged and captively held therein; and
• a switch housing in which the switching mechanism housing is arranged and captively held therein, the switch housing having a stationary contact part which functions as a mating contact to the movable contact part;

• wherein the rear derailleur housing surrounds the rear derailleur unit by a first housing side, a second housing side opposite the first housing side and a housing peripheral side running between and transversely to the first and second housing sides and has an opening on the first housing side through which the movable contact part is preferably directly connected to the stationary contact part interacts,
• wherein the switching mechanism housing has an electrically conductive base body which forms at least part of the second housing side, this part of the second housing side forming a freely accessible outside of the switch, and
• wherein the switch further has an insulator which electrically insulates the base body of the switching mechanism housing from the switch housing and is arranged inside the switch housing.

The switch according to the invention therefore comprises a switching mechanism which has an additional switching mechanism housing in which the switching mechanism unit, which has the bimetal snap disk and the movable contact part, is captively held. The rear derailleur housing surrounds the rear derailleur unit both from a first housing side and from a second housing side opposite the first housing side, as well as from a housing peripheral side running between and across the first and second housing sides. The rear derailleur housing thus at least partially surrounds the rear derailleur unit from all six spatial directions, so that the rear derailleur cannot fall out of the rear derailleur housing.

The rear derailleur, including the rear derailleur unit and including the rear derailleur housing surrounding the rear derailleur unit, can be pre-produced as a semi-finished product before it is inserted into the switch. The rear derailleur, pre-produced as a semi-finished product, can be kept in stock as bulk goods. During this bulk storage, the fragile components of the switching mechanism, in particular the bimetal snap disk and the movable contact part, are protected by the switching mechanism housing. Damage to these fragile components during storage of bulk goods is largely impossible, since the fragile components of the rear derailleur unit are securely encapsulated in the rear derailleur housing.

However, the rear derailleur housing not only offers the advantage of safely storing the rear derailleur unit arranged therein, it also enables a much simpler way of producing the temperature-dependent switch. Unlike a conventional switch housing, the rear derailleur housing that is now additionally provided is not a closed housing in which the rear derailleur is hermetically sealed, but rather a partially open housing that has an opening on the first side of the housing through which the movable contact part of is accessible outside the rear derailleur housing. The rear derailleur, together with the rear derailleur housing, can thus be inserted as a unit into a simplified switch housing, which forms the final switch housing. A stationary contact part is arranged on this switch housing, which acts as a counter-contact to the movable contact part and interacts with the movable contact part of the rear derailleur through the opening in the rear derailleur housing. Preferably, the movable contact part interacts directly with the stationary contact part through the opening. In the low temperature position of the switch, the movable contact part touches the stationary contact part through the opening.

When producing the temperature-dependent switch, the switching mechanism according to the invention, together with its switching mechanism housing, can first be pre-produced as a semi-finished product and then inserted as a whole into the switch housing. This not only simplifies the storage of the switching mechanism, but also the production of the temperature-dependent switch many times over.

The second housing side and the housing peripheral side of the switching mechanism housing are preferably each closed housing sides, while the first housing side is only a partially closed or a partially opened housing side due to the opening mentioned.

However, since the first housing side of the rear derailleur housing is also at least partially closed and also at least partially surrounds the rear derailleur unit from this side, the rear derailleur unit is securely encapsulated in the rear derailleur housing. This opens up the possibility of carrying out a functional test of the switching mechanism with the pre-produced semi-finished product before it is installed in the switch housing.

The switching mechanism housing has an electrically conductive base body which forms at least part of the second housing side. The base body preferably forms the entire second housing side and at least part of the housing peripheral side.

When the switch is fully assembled, the electrically conductive base body formed on the second housing side of the switching mechanism housing forms a freely accessible outside of the switch. This part of the rear derailleur housing is not surrounded by the switch housing when the switch is fully assembled. This part of the switchgear housing can therefore serve as the direct electrical connection surface of the switch. A part of the outside of the switchgear housing, which is electrically insulated from the switchgear housing by means of an insulator, preferably serves as the second electrical connection.

The switching mechanism housing is therefore preferably only partially, but not completely, arranged in the switch housing. At least the second housing side of the rear derailleur housing is freely accessible from the outside.

This type of arrangement, in which the rear derailleur housing is only partially, but not completely, surrounded by the rear derailleur housing, results in a very compact Structure of the switch. In addition, the switch is designed to be extremely pressure-resistant due to the additional switch housing provided.

The above-mentioned task is therefore completely solved.

According to one embodiment, the insulator has a ring body.

This ring body can be designed in the shape of a circular ring when viewed from above. However, when viewed from above, the ring body can in principle also have a polygonal outer contour.

The term “ring body” is therefore to be understood generally. It refers to any body that has a circumferentially closed contour. For example, the outer contour viewed in the top view can also be elliptical or have any free shape. The ring body does not necessarily have to be hollow cylindrical or toroidal, although this is preferred.

The design of the insulator as a ring body has the advantage that the insulator electrically insulates the switching mechanism housing along the entire circumference from the switch housing. In addition, such an annular body can be arranged in the switch housing to save space. The ring body is also preferably designed to be solid, so that the insulator forms a mechanically stable component of the switch, which can also serve to support other components of the switch and is easy to handle during assembly of the switch.

According to a further embodiment, the insulator is attached to the base body of the rear derailleur housing.

In this embodiment, the insulator thus forms a component belonging to the switching mechanism. The insulator can therefore be connected to the base body of the switching mechanism housing before the switch is installed and can be kept in stock together with it as a semi-finished product. When installing the switch, the rear derailleur can then together with the insulator as a unit in the switch housing. This leads to a significant simplification of the assembly of the switch, in particular because an alignment and positioning of the switching mechanism housing relative to the insulator no longer has to be carried out during the switch assembly. Both components are already positioned in relation to each other in advance.

Furthermore, the attachment of the insulator to the base body of the rear derailleur housing contributes to the compact and pressure-stable structure of the switch.

According to a further embodiment, at least one holding element is formed on the base body of the switching mechanism housing, by means of which the insulator is fastened to the base body. Preferably, several such holding elements are formed on the base body of the rear derailleur housing. Particularly preferably, the at least one holding element is formed integrally on the base body.

The insulator can therefore be easily connected to the rear derailleur housing. Preferably, the at least one holding element is one or more holding claws, which can be produced by bending or flanging a free section of the base body.

According to a further embodiment, the base body of the switching mechanism housing is designed in one piece.

This one-piece design of the rear derailleur housing further contributes to the compact and pressure-stable design of the switch. In addition, this significantly simplifies the assembly of the switch and reduces the number of components of the switch.

According to a further embodiment, an outer peripheral surface of the insulator rests on an inner peripheral surface of the switch housing. Preferably, the shape of the outer peripheral surface of the insulator is adapted to the shape of the inner peripheral surface of the rear derailleur housing.

This configuration is particularly advantageous if the insulator is attached to the base body of the switching mechanism housing. Inserting the switchgear housing and the insulator attached to it then leads directly to the correct positioning and alignment of the switchgear relative to the stationary mating contact arranged on the switch housing. The movable contact part of the switching mechanism is therefore correctly positioned relative to the stationary contact part without any further measures.

According to a further embodiment, the insulator forms at least a part of the peripheral side of the rear derailleur housing and/or a part of the first housing side of the rear derailleur housing.

The insulator thus insulates the rear derailleur housing from the switch housing along the first housing side and/or the peripheral side of the rear derailleur housing.

According to a further embodiment, an inner circumferential surface of the insulator delimits the opening in the radial direction.

The opening on the first side of the rear derailleur housing is then formed by the insulator. The rear derailleur unit arranged inside the rear derailleur housing is therefore well protected. The insulator arranged on the rear derailleur housing prevents the rear derailleur unit from falling out of the rear derailleur housing, which is particularly advantageous during bulk storage of the rear derailleur, which can be pre-produced as a semi-finished product. In addition, this configuration has the advantage that the bimetal snap-action disk can be supported on the insulator in its high-temperature configuration.

A diameter of the opening is preferably smaller than a diameter of the bimetal snap disk measured parallel thereto.

The bimetal snap-action disk is therefore held securely in the rear derailleur housing and cannot come out of it even if there is a corresponding shock.

According to a further embodiment, the switching mechanism is set up to hold the switch in a low-temperature position below a response temperature of the bimetal snap-action disk, in which the switching mechanism establishes an electrical connection via the movable contact part between the base body of the switching mechanism housing and the stationary contact part arranged on the switch housing , and if the response temperature is exceeded, to move the switch to a high-temperature position in which the switching mechanism interrupts the electrical connection.

The electrical connection is interrupted in the high-temperature configuration of the switch in that the bimetal snap-action disk snaps from its low-temperature configuration to its high-temperature configuration when its response temperature is exceeded, thereby lifting the movable contact part from the stationary contact.

According to a preferred embodiment of the present invention, the bimetal snap disk is supported in its high-temperature configuration on a support surface arranged on the first housing side of the switching mechanism housing, which is formed on the base body or on the insulator. The bimetal snap disk keeps the movable contact part at a distance from the stationary contact.

Since the rear derailleur unit, as already mentioned, is encapsulated in the rear derailleur housing according to the present invention and the bimetal snap disk is supported in its high-temperature configuration on the support surface mentioned inside the rear derailleur housing, a functional check of the rear derailleur can also be carried out with the rear derailleur pre-produced as a semi-finished product carry out, i.e. before the rear derailleur is installed in the switch housing and the switch is completely assembled. The bimetal snap disk can then assume its two temperature-dependent configurations inside the rear derailleur housing.

This is not possible with conventional switches because the bimetal snap-action disk is in its position due to the lack of the now specially provided rear derailleur housing High-temperature configuration is supported on the switch housing, so that a functional check is then only possible when the switch is fully assembled.

According to a further embodiment, the switching mechanism unit further has a spring snap disk coupled to the movable contact part, which is supported in the low-temperature position of the switch on an inner surface arranged on the second housing side inside the switching mechanism housing. This inner surface is preferably an inner surface of the electrically conductive base body of the switching mechanism housing.

The additional provision of such a spring snap-action disk has the particular advantage that the bimetal snap-action disk is thereby relieved. In the low-temperature configuration of the switch, i.e. when the circuit is closed via the switch, the spring snap disk serves as a current-carrying component according to this embodiment. The bimetal snap-action disk, however, is then not a current-carrying component.

In addition, in the low-temperature position of the switch, the spring snap disk generates the closing pressure with which the movable contact part is pressed against the stationary contact part. The bimetal snap-action disk can, however, be mounted with almost no force in the low-temperature position of the switch. This has a positive effect on the service life of the bimetal snap-action disk and ensures that the switching point, i.e. the response temperature of the bimetal snap-action disk, does not change even after many switching cycles.

According to a further embodiment, the part of the second housing side of the switching mechanism housing, which forms a freely accessible outside of the switch, has an outwardly curved, dome-shaped or cup-shaped section.

This dome or cup-shaped section of the switching mechanism housing preferably protrudes at least partially from the switch housing. At this point, “curved outwards” means that the dome or pot-shaped section is from the point of view of the Switch housing is curved outwards, i.e. from the inside of the switch housing. The outside of the switch is convexly curved at this point.

This design of the rear derailleur housing makes the switch extremely pressure-stable. In addition, the dome or cup-shaped section can be used very easily as an external connection surface of the switch.

According to one embodiment, the outwardly curved, dome-shaped or cup-shaped section has a first contact surface which lies in a plane with a second contact surface arranged on the switch housing.

Preferably, the second contact surface at least partially surrounds the first contact surface. Particularly preferably, the second contact surface completely surrounds the first contact surface.

When the dome or cup-shaped section, which forms a first contact surface, is arranged in a plane with a second contact surface arranged on the switch housing, the temperature-dependent switch is also suitable for SMD (Surface Mounted Device) mounting. The switch can then be attached very easily to a flat circuit board because the electrical contact surfaces lie in a common plane.

According to a further embodiment, a circumferential space between the switching mechanism housing and the switch housing is filled with insulating compound. The insulating compound is preferably a varnish which is used to fill the space between the switching mechanism housing and the switch housing.

This seals the inside of the switch, where the rear derailleur is located, extremely well. In addition, the insulating and sealing compound ensures a mechanically stable attachment of the rear derailleur housing in the switch housing.

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

Fig. 1

eine schematische Schnittansicht des temperaturabhängigen Schalters gemäß einem ersten Ausführungsbeispiel der vorliegenden Erfindung, wobei der Schalter in seiner Tieftemperaturstellung gezeigt ist;

Fig. 2

eine schematische Schnittansicht des in Fig. 1 gezeigten Schalters, wobei der Schalter in seiner Hochtemperaturstellung gezeigt ist;

Fig. 3

eine schematische Schnittansicht des temperaturabhängigen Schalters gemäß einem zweiten Ausführungsbeispiel der vorliegenden Erfindung, wobei der Schalter in seiner Tieftemperaturstellung gezeigt ist;

Fig. 4A-4C

schematische Schnittansichten, die einzelne Bearbeitungsschritte während der Herstellung des temperaturabhängigen Schalters gemäß dem in Fig. 1 gezeigten Ausführungsbeispiel veranschaulichen; und

Fig. 5

eine schematische Draufsicht von unten auf das in dem temperaturabhängigen Schalter verwendete Schaltwerk gemäß dem in Fig. 1 gezeigten ersten Ausführungsbeispiel.

Exemplary embodiments of the invention are shown in the drawings and are explained in more detail in the following description. Show it:

Fig. 1

a schematic sectional view of the temperature-dependent switch according to a first embodiment of the present invention, the switch being shown in its low-temperature position;

Fig. 2

a schematic sectional view of the in Fig. 1 switch shown, the switch being shown in its high temperature position;

Fig. 3

a schematic sectional view of the temperature-dependent switch according to a second embodiment of the present invention, the switch being shown in its low-temperature position;

Figs. 4A-4C

schematic sectional views showing individual processing steps during the production of the temperature-dependent switch according to in Fig. 1 illustrate the exemplary embodiment shown; and

Fig. 5

a schematic top view from below of the switching mechanism used in the temperature-dependent switch according to in Fig. 1 shown first embodiment.

Fig. 1-2 show a first exemplary embodiment of the switch according to the invention, each in a schematic sectional view. The switch is marked in its entirety with the reference number 100.

The switch 100 has a temperature-dependent switching mechanism 10, which is arranged in an electrically conductive switch housing 12.

The rear derailleur 10 has a functional rear derailleur unit 14 and a rear derailleur housing 16 surrounding this rear derailleur unit 14. The rear derailleur housing 16 at least partially surrounds the rear derailleur unit 14 from all six spatial directions. However, as explained in detail below, the rear derailleur housing 16 is designed as a partially open housing, so that the rear derailleur unit 14 is accessible from at least one spatial direction, preferably from only one spatial direction, from outside the rear derailleur housing 16.

Due to the fact that the rear derailleur housing 16 at least partially surrounds the rear derailleur unit 14 from all six spatial directions, the rear derailleur unit 14 is held captively in the rear derailleur housing 16. The rear derailleur unit 14 cannot therefore be removed from the rear derailleur housing 16.

As long as the rear derailleur 10 is not installed in the switch 100 or its switch housing 12, there is preferably a certain amount of play between the rear derailleur unit 14 and the rear derailleur housing 16. In the in Fig. 1 However, in the installed state of the switch 100 shown, the switching mechanism unit 14 is firmly clamped. In the in Fig. 1 In the low temperature position of the switch 100 shown, the switching mechanism unit 14 is clamped between the switch housing 12 and the switching mechanism housing 16.

The rear derailleur unit 14 is constructed in three parts according to the present exemplary embodiment. The switching mechanism unit 14 has a temperature-dependent bimetal snap-action disk 18, a temperature-independent spring snap-action disk 20 and a movable contact part 22. The bimetal snap disk 18 and the spring snap disk 20 are held captively on the contact part 22. The rear derailleur unit 14 can thus be pre-produced as a semi-finished product and then inserted as a whole into the rear derailleur housing 16 (see Fig. 4A ).

The rear derailleur 10 together with the rear derailleur unit 14 and the rear derailleur housing 16 also form a semi-finished product for the temperature-dependent switch 100 that is later produced from it. Since both the three components 18, 20, 22 of the rear derailleur unit 14 are captively connected to one another, as is the rear derailleur unit 14 in the rear derailleur housing 16 is held captively, the switching mechanism 10 can be kept in storage as bulk material until it is installed in the temperature-dependent switch 100.

The rear derailleur housing 16 surrounds the rear derailleur unit 14 by a first housing side 24, a second housing side 26 opposite the first housing side 24 and a housing peripheral side 28 running between and transversely to the first and second housing sides 24, 26.

Preferably, the rear derailleur housing 16 completely surrounds the rear derailleur unit 14 from both the second housing side 26 and the housing peripheral side 28. The second housing side 26 and the housing peripheral side 28 therefore preferably form closed housing sides of the rear derailleur housing 16. Only the first housing side 24 is a partially open housing side of the rear derailleur housing 16.

In other words, the housing peripheral side 28 surrounds the switching mechanism unit 14 along the entire circumference, i.e. from a total of four spatial directions aligned orthogonally to one another. Furthermore, the switching mechanism housing 16 completely surrounds the switching mechanism unit 14 from a further spatial direction, namely from a spatial direction aligned orthogonally to the second housing side 26. Only from the sixth spatial direction, which is aligned orthogonally to the first housing side 24, does the rear derailleur housing 16 only partially surround the rear derailleur unit 14.

On the first housing side 24, the rear derailleur housing 14 has an opening 30 through which the movable contact part 22 is accessible from outside the rear derailleur housing 16. Through this opening 30 in the switching mechanism housing 16, the movable contact part 22 of the switching mechanism 10 interacts with a stationary contact part 32, which is arranged on an inside 34 of the switch housing 12.

A diameter D of the opening 30 is smaller than a diameter D ₂ of the bimetal snap disk 18 and/or the spring snap disk 20, measured parallel thereto. The movable contact part 22 is therefore accessible from outside the switching mechanism housing 16 through the opening 30 However, the bimetal snap-action disk 18 and the spring-action snap-action disk 20 cannot detach or emerge from the rear derailleur housing 16.

The switching mechanism housing 16 has a base body 36 which is made of an electrically conductive material, for example metal. In the exemplary embodiment shown here, this electrically conductive base body 36 forms the second housing side 26 and the housing peripheral side 28 of the switching mechanism housing 16.

An upper part of the base body 36, which forms the second housing side 26, simultaneously forms a freely accessible outside of the switch 100. The first housing side 24 and the housing peripheral side 28 are arranged completely inside the switch housing 12 and are therefore not accessible from outside the switch 100.

The first housing side 24 of the rear derailleur housing 16 is according to in Fig. 1 and 2 shown embodiment formed by an insulator 38. This can be, for example, a plastic insulator. The insulator 38 is attached to the base body 36 of the rear derailleur housing 16 on the underside of the rear derailleur housing 16. For this purpose, several retaining claws 40 are provided, which are in Fig. 1 and 2 are shown in dashed lines.

The base body 36 of the switching mechanism housing 16 is preferably designed in one piece. The retaining claws 40 are preferably integrally connected to the base body 36.

According to the in Fig. 1 and 2 In the exemplary embodiment shown, the switching mechanism housing 16 is constructed in two parts, with the base body 36 and the insulator 38 attached to it. Of course, instead of retaining claws 40, other types of retaining elements can also be used to connect the insulator 38 to the base body 36. Likewise, the base body 36 can also be glued to the insulator 38.

The insulator 38 is designed as a ring body. Its shape is preferably adapted to the shape of the rear derailleur housing 12. The insulator 38 lies on the inside 34 of the bottom of the switch housing 12 with an insulating film 42 in between. Although the insulating film 42 improves the electrical insulation and the tightness of the switch 100, it is not necessarily necessary.

With its outer peripheral surface 44, the insulator 38 rests on an inner peripheral surface 46 of the switch housing 12 (either directly or with the insulating film 42 in between). An inner circumferential surface 48 of the insulator 38 delimits the opening 30 provided on the first housing side 24 of the rear derailleur housing 16 in the radial direction.

The switch housing 16 is inserted into the switch housing 12 together with the insulator 38 during the manufacture of the switch 100. The switch housing 12 is preferably formed in one piece from an electrically conductive material, preferably metal. The switch housing 12 is designed like a pot. It has a base 50 and a side wall 52 running transversely thereto in the circumferential direction, the upper edge 54 of which is bent inwards in the direction of the central axis of the rear derailleur housing after the rear derailleur housing has been inserted in order to fix the rear derailleur housing 16 in the switch housing 12.

The space 56 between the switching mechanism housing 16 and the switch housing 12 is filled with insulating compound 58. The insulating compound 58 provides a mechanical seal that prevents external liquids or contaminants from entering the interior of the switch 100. In this way, a sealed switch housing 12 is created, in which the switching mechanism housing 16 is held captively.

Since the switching mechanism housing 12 and the base body 36 of the switching mechanism housing 16 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 for the electrical connection of the switch 100. For example, the outside 60 of the base 50 of the switch housing 12 act as a first electrical connection and the outside 62 of the part of the base body 36 of the switching mechanism housing 16 that is freely accessible from the outside on the second housing side 26 function as a second electrical connection.

The rear derailleur 10 is arranged clamped between the base body 36 of the rear derailleur housing 16 and the switch housing 12 when the switch 100 is in the assembled state. The insulator 38 ensures electrical insulation of the base body 36 of the switching mechanism housing 16 from the switch housing 12.

In this way it is ensured that an electrical contact established via the switch 100 between the switch housing 12 and the rear derailleur housing 16 can only be established via the rear derailleur 10. This electrical contact between the switch housing 12 and the rear derailleur housing 16, which is established via the switch 100, is only established by the rear derailleur 10 in the low-temperature position of the switch 100 (cf. Fig. 1 and 2 ).

In the in Fig. 1 In the low temperature position of the switch 100 shown, the temperature-independent spring snap-action disk 20 is in its first configuration and the temperature-dependent bimetal snap-action disk 18 is in its low-temperature configuration. The spring snap disk 20 presses the movable contact part 22 against the stationary contact part 32, which acts as a counter contact. The switch 100 is thus in its closed position, in which an electrically conductive connection between the outside 62 of the switching mechanism housing 16, which acts as the first switch connection acts, and the outside 60 of the switch housing 12, which functions as a second switch connection, is made via the spring snap disk 20, the movable contact part 22 and the stationary contact part 32.

The contact pressure between the movable contact part 22 and the stationary contact part 32 is generated by the spring snap disk 20. In this state, however, the bimetal snap disk 18 is mounted in the rear derailleur housing 16 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 18 arranged therein increases to the switching temperature of the bimetal snap-action disk 18 or above the switching temperature, the bimetal snap-action disk 18 snaps from its position Fig. 1 shown concave low temperature position in their in Fig. 2 shown convex high temperature position. During this snapping, the bimetal snap disk 18 is supported with its outer edge 64 on a support surface arranged on the top of the insulator 38. As a result, at the same time the spring snap disk 20 bends upwards at its center, so that the spring snap disk 20 moves away from its in Fig. 1 shown, first stable geometric configuration in their in Fig. 2 shown, second geometrically stable configuration snapped around.

Fig. 2 shows the high temperature position of the switch 100, in which it is open. The circuit is then interrupted.

When the device to be protected and thus the switch 100 together with the bimetal snap-action disk 18 then cool down again, the bimetal snap-action disk 18 snaps back into its low-temperature position when the switch-back temperature is reached, which is also referred to as the return temperature, as in, for example Fig. 1 is shown. This makes it possible to achieve reversible switching behavior.

Of course, it is also possible for the switch 100 to be prevented from switching back to the high-temperature position after it has been snapped once by a corresponding closing lock. A large number of such closing locks, which are used in particular in one-time switches in which switching back is to be prevented, are already known from the prior art.

It is also possible to equip the rear derailleur unit 14 without a spring snap washer 20. In such a case, the switching mechanism unit 14 then “only” has the bimetal snap disk 18 and the movable contact part 22. The bimetal snap disk 18 then not only ensures the switching behavior, but also simultaneously generates the contact pressure in the low-temperature position of the switch 100 the movable contact part 22 and the stationary contact part 32. The bimetal snap disk 18 is then used as a current-carrying component of the switching mechanism 10.

Fig. 3 shows a schematic sectional view of a second exemplary embodiment of the switch 100. In this regard, the differences from the switch 100 according to FIG Fig. 1 and 2 shown first embodiment explained. Since the general functionality of the in Fig. 3 Switch 100 shown does not differ from that in Fig. 1 and 2 Switch 100 shown differs, this will not be explicitly discussed again.

A difference of the in Fig. 3 Switch 100 shown according to the second exemplary embodiment of the present invention lies in its even flatter design. In particular, the rear derailleur housing 16 is designed to be even flatter here. While the part of the second housing side 26 of the rear derailleur housing 16, which forms a freely accessible outside of the switch 10, in Fig. 1 has a dome-shaped section 66, this part 68 of the rear derailleur housing 16 is according to the in Fig. 3 shown embodiment pot-shaped. This cup-shaped section 68 has a flat contact surface 70 on its upper side, which is arranged in a plane E with a second contact surface 72 arranged on the switch housing 12. These two contact surfaces 70, 72 are suitable for SMD mounting of the switch 100. The switch 100 can therefore be mounted very easily overhead, so to speak, on a flat circuit board.

The second contact surface 72, which is arranged on the surface of the switch housing 12, preferably completely surrounds the first contact surface 70 along the entire circumference of the switch 100. The first contact surface 70 is preferably circular. The second contact surface 72 is preferably designed in the shape of a circular ring.

The switch housing 16 is also inside the switch according to the in Fig. 3 second exemplary embodiment shown is designed to be flatter. The base body 36 of the switching mechanism housing 16 is in turn made in one piece from an electrically conductive material, for example made of metal. In this embodiment too, the rear derailleur unit 14 is encapsulated in the rear derailleur housing 16. The rear derailleur housing 16 at least partially surrounds the rear derailleur unit 14 from all six spatial directions. The first housing side 24 of the switching mechanism housing 16 is in turn designed as a partially open housing side which has a central opening 30 through which the movable contact part 22 interacts directly with the stationary contact part 32. In the in Fig. 1 and 3 In the low temperature position of the switch 100 shown, the movable contact part 22 touches the stationary contact part 32 through the opening 30.

The opening 30 is limited in the radial direction by the base body 36 of the rear derailleur housing 16. On the first housing side 24, the base body 36 of the rear derailleur housing 16 has a circumferential edge 74 that is folded inwards. Instead of such an edge 74, however, individual webs can also be provided which protrude radially inwards from the housing peripheral side 28.

The edge 74 or the webs mentioned serve according to the in Fig. 3 shown embodiment as a counterholder for the bimetal snap-action disk 18. The edge 74 has a support surface 63 on which the bimetal snap-action disk 18 can be supported in its high-temperature position.

Unlike the one in Fig. 1 and 2 In the first exemplary embodiment shown, the bimetal snap disk 18 is no longer supported in its high-temperature position on the insulator 38, but on the base body 36 of the switching mechanism housing 16 itself, namely on the edge 74 or the webs mentioned.

Another difference is the slightly different design of the insulator 38. The insulator 38 is also designed here as a ring body, the outer peripheral surface of which rests on the inner peripheral surface of the switch housing 12. However, the insulator 38 here has an approximately L-shaped cross section. The base body of the switching mechanism housing 16 rests on an inner peripheral shoulder 76 of the insulator 38.

According to this embodiment, too, it is preferred that the insulator 38 as part of the switching mechanism housing 16 is inserted as a common unit into the switch housing 12 when the switch 100 is manufactured. The insulator 38 is therefore preferably connected to the base body 36 of the rear derailleur housing 16 here too. This connection can be made using one or more holding elements, for example at least one holding claw. Alternatively, the insulator 38 can be glued, welded or soldered to the base body 36 of the rear derailleur housing 16.

Fig. 4A-C illustrate in a schematic manner several sequentially executed work steps in the assembly of the switch 100 according to the first exemplary embodiment.

In a first assembly step, the switching mechanism unit 14, which has the bimetal snap-action disc 19, the spring-action snap-action disc 20 and the movable contact part 20, is inserted into the base body 36 of the switching mechanism housing 16 from below. The preformed base body 36 can be designed, for example, as a deep-drawn component. In Fig. 4A the first housing side 25 is still completely open, so that the rear derailleur unit 14 can be easily inserted from below. A part of the housing peripheral side 28 as well as the second housing side 26 are designed as closed housing sides. From the housing peripheral side 28, several pre-formed retaining claws 74 protrude vertically downwards, approximately from the dashed line 78.

In a second assembly step, the insulator 38 is then pushed onto the retaining claws 40. For this purpose, the insulator 38 preferably has a plurality of through holes 8 distributed over the circumference, through which the retaining claws are inserted. The retaining claws 40 are then folded inwards, as indicated by the arrows 82, in order to fix the insulator 38 on the base body 36 of the rear derailleur housing 16. The rear derailleur 10 is now completed.

The completed switching mechanism 10, which can be stored as a semi-finished product in bulk storage, is in the upper part of Fig. 4C shown. Fig. 5 shows a top view from below of the rear derailleur 10, which in particular shows the previously mentioned type of Attachment of the insulator 38 to the base body 36 of the rear derailleur housing 16 can be seen again.

In the last assembly step, which in Fig. 4C is shown, the switch mechanism 10, pre-produced as a semi-finished product, is inserted into the switch housing 12 and the switch housing 12 is closed by folding over the upper edge 54 (see arrows 84).

As a final process step, not shown here, the insulating and sealing compound 58 is introduced into the space 56 between the switching mechanism housing 16 and the switch housing 12.

Claims (15)

Temperature-dependent switch (100), comprising: - a temperature-dependent switching mechanism (10) with a switching mechanism unit (14), which has a movable contact part (22) coupled to a bimetal snap-action disk (18), and with a switching mechanism housing (16), in which the switching mechanism unit (14) is arranged and is held captively therein; and - a switch housing (12) in which the switching mechanism housing (16) is arranged and captively held therein, the switch housing (12) having a stationary contact part (32) which acts as a mating contact to the movable contact part (22); wherein the rear derailleur housing (16) extends the rear derailleur unit (14) from a first housing side (24), a second housing side (26) opposite the first housing side (24) and one extending between and transversely to the first and second housing sides (24, 26). Surrounds the peripheral side of the housing (28) and has an opening (30) on the first side of the housing (24), through which the movable contact part (22) interacts with the stationary contact part (32), wherein the switching mechanism housing (16) has an electrically conductive base body (36) which forms at least part of the second housing side (26), this part of the second housing side (26) forming a freely accessible outside (62) of the switch (100), and wherein the switch (100) further has an insulator (38) which electrically insulates the base body (36) of the switching mechanism housing (16) from the switch housing (12) and is arranged inside the switch housing (12). Temperature dependent switch according to claim 1, wherein the insulator (38) comprises an annular body. Temperature-dependent switch according to claim 1 or 2, wherein the insulator (38) is attached to the base body (36) of the switching mechanism housing (16). Temperature-dependent switch according to claim 3, wherein at least one holding element (40) is formed on the base body (36) of the switching mechanism housing (16), by means of which the insulator (38) is fastened to the base body (36). Temperature-dependent switch according to one of the preceding claims, wherein the base body (36) of the switching mechanism housing (16) is designed in one piece. Temperature-dependent switch according to one of the preceding claims, wherein an outer peripheral surface (44) of the insulator (38) abuts an inner peripheral surface (46) of the switch housing (12). Temperature-dependent switch according to one of the preceding claims, wherein the insulator (38) forms at least part of the peripheral housing side (28) of the switching derailleur housing (16) and/or a part of the first housing side (24) of the switching derailleur housing (16). Temperature-dependent switch according to one of the preceding claims, wherein an inner peripheral surface (48) of the insulator (38) radially delimits the opening (30). Temperature-dependent switch according to one of the preceding claims, wherein a diameter (D ₁ ) of the opening (30) is smaller than a diameter (D ₂ ) of the bimetal snap-action disk (18) measured parallel thereto. Temperature-dependent switch according to one of the preceding claims, wherein the switching mechanism (10) is designed to hold the switch (100) in a low-temperature position below a response temperature of the bimetal snap-action disk (18), in which the switching mechanism (10) via the movable contact part (22) establishes an electrical connection between the base body (36) of the switching mechanism housing (16) and the stationary contact part (32) arranged on the switch housing (12), and when the response temperature is exceeded Bring the switch (100) into a high-temperature position in which the switching mechanism (10) interrupts the electrical connection. Temperature-dependent switch according to claim 10, wherein the bimetal snap disk (18) is designed to snap from a geometrically stable low-temperature configuration to a geometrically stable high-temperature configuration when the response temperature is exceeded, and wherein the bimetal snap disk (18) is in its high-temperature configuration on a on the first housing side (24) of the switching mechanism housing (16) is supported on the support surface (63) which is formed on the base body (36) or on the insulator (38), and the movable contact part (22) is at a distance from the stationary contact ( 32) holds. Temperature-dependent switch according to claim 10 or 11, wherein the switching mechanism unit (10) further has a spring snap disk (20) coupled to the movable contact part (22), which is located in the low-temperature position of the switch (100) on one on the second housing side (26 ) is supported on the inner surface arranged inside the rear derailleur housing (16). Temperature-dependent switch according to one of the preceding claims, wherein the part of the second housing side (26) of the switching mechanism housing (16), which forms a freely accessible outside (62) of the switch (100), has an outwardly curved, dome-shaped or cup-shaped section (66 , 68). Temperature-dependent switch according to claim 13, wherein the outwardly curved, dome-shaped or cup-shaped section (66, 68) has a first contact surface (70) which is in a plane (E.) with a second contact surface (72) arranged on the switch housing (12). ) lies. Temperature-dependent switch according to one of the preceding claims, wherein a circumferential space (56) between the switching mechanism housing (16) and the switch housing (12) are filled with insulating compound (58).

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