EP2806446A1 - Switching unit for mounting an actuator - Google Patents

Abstract

Described is a switching unit 10, 110 with a receiving area 20 for receiving an actuator 14. In the receiving area 20, a pivoting element 36 is arranged, which is designed so that it performs a pivotal movement in a direction of retraction in the receiving area 20 in a translational movement of the actuator 14 , A switch actuating element 38 is displaceable in an actuating direction for actuating an electrical switch element 52, 54. A propulsion coupling 42 is provided to move the switch actuator 38 in the direction of actuation. In order to obtain a switching unit and switch assembly with small dimensions and interference-proof detection even under the action of liquids, the propulsion coupling 42 is coupled to the pivot member 36 via a shaft 40, so that an adjustment of the switch actuating element 38 takes place during the pivoting movement.

Description

The invention relates to a switching unit, a switch assembly with a switching unit and a security system for a door, in particular for an elevator door.

In the context of the invention, electrical switching units are considered, which perform an electrical switching function in dependence on the position of an associated actuator. Such switching units, or switch assemblies formed of switching units and associated actuators can be used for detecting the position of two mechanical elements relative to each other, wherein the switching unit is arranged on one of the elements of the actuator and on the other element, so that in a predetermined receiving position the actuator is received in a receiving area of the switching unit and thereby a switching function is performed.

In particular, such switching units and switch assemblies can be used as a safety switch or machine switch, for example. In the form of a limit switch or door contact.

In elevator systems switching units are used as a door contact, ie as a safety switch for monitoring the closed position of doors, eg. For the cabin doors or for storey doors. The G 8120 397 shows such a safety switch with a switch housing and a control housing, in which a switch is controlled by the stroke of a moving from the control housing plunger. In the control housing, a control roller is pivotable about a shaft. To the control roller and the plunger a toggle lever is articulated so that is raised or lowered at a pivoting of the control roller, the plunger. The actuation takes place by an actuating bow, which is inserted through a slot in the control housing, comes into contact with a control wing of the control roller and pivoted on further forward sliding the control roller. A blocking wing of the control roller engages in a window of the control bar and serves to ensure the inevitability of the contact operation when pulling out the actuating bracket.

The publication WO 2012/113102 A1 describes an electrical switch with two spaced electrical contacts. An actuator is inserted through an opening in a housing and there caused by engagement with a driver, the rotation of a main shaft. As a result, a translational force is exerted on a contact holder, through which the contacts are closed. When the actuator is pulled out, engagement with the driver results in rotation in the opposite direction and separation of the contacts.

The publication DE 39 43 376 C1 describes a safety switch for protective covers. In a multi-part housing, a ratchet wheel is rotatably mounted about an axis on a shaft. The ratchet is operatively connected to the plunger of a switch via circumferentially positively driven rollers in a cam track of the ratchet wheel. Alternatively, the operative connection between plunger and ratchet wheel can also be made by means of a connecting rod. The switch with electrical contacts is housed in a closed switching space of the housing into which the plunger is guided. The plunger is sealed against the switch room by means of a seal in the region of the passage. A frame-like actuator is used for switching the switching wheel. A cross bar on the actuator engages in a slot of the switching frame.

The publication JP 08285183 A concerns a switch, for example on the door of a copier. An actuator has an elastic member and an actuator member which comes into contact with a switch. When closing the door, the actuator part is guided by guides to the switch. When the door is open, the elastic part prevents damage when exposed.

The publication DE 295 04 673 U1 relates to an actuator for a safety position switch. The actuator engages an insertion channel of the safety position switch with a key element that is resiliently pivotally attached to a mounting member.

It is an object of the invention to provide a switching unit, a switch assembly and a security system for a door in which small dimensions and yet a fail-safe detection is ensured even under the action of liquids.

This object is achieved by a switch unit according to claim 1, a switch assembly according to claim 12 and a safety system according to claim 14. Dependent claims relate to advantageous embodiments of the invention.

The switching unit according to the invention has a receiving area for receiving an actuator. The recording of the actuator is preferably carried out in the form of a translational movement of the actuator in a retraction in the receiving area. The receiving area may in principle be open to several sides, but preferred is a receiving chamber enclosed by a housing except for an insertion.

In the receiving area, a pivoting element is arranged and designed such that the receptacle of the actuator in the retraction direction leads to a pivoting movement of the pivoting element. For this purpose, the actuator applies to the pivot element and causes the pivoting movement with further retraction. While possible embodiments of the pivoting element will be described in more detail below, it is generally preferred that the pivoting element has at least one part, designed, for example, as a leg, with which the actuator comes into contact when entering the receiving space and thus effects the pivoting movement.

The switching unit further includes an electrical switch element and a switch actuating element therefor, the electrical switch element closing or interrupting an electrical contact in response to the actuation by the switch actuating element. The switch actuating element is displaceable in an actuating direction to effect the actuation of the electrical switch element.

A propulsion coupling is provided to adjust the switch actuator in the direction of actuation. In this case, the propulsion coupling is coupled to the pivoting element via a shaft, so that an adjustment of the switch actuating element takes place during the pivoting movement of the pivoting element. Thus, the inclusion of the actuator in the receiving area causes a pivoting movement of the pivot member, which is transmitted via the shaft to the drive coupling and leads to an adjustment of the switch actuating element in the actuating direction, which in turn actuates the electric Switch element is done.

Thus, the electrical switch element is mechanically coupled via said elements with the pivot member, wherein the proposed type of mechanical coupling brings a number of advantages. Thus, by the only indirect coupling of the movement of the actuator and the movement of the switch operating element a suitable adaptation of operating paths and mechanical tolerances in particular well possible. While a very accurate guidance and positioning of the switch actuating element is advantageous for a safe electrical switching operation, the movement of the actuator in the receiving area can be reliably detected despite greater mechanical tolerances. In particular, as will be explained in connection with advantageous embodiments, a Überfahrweg be ensured in which after a successful tripping of the switch operation further movement of the actuator in the retraction direction is easily possible.

For this purpose, the receiving area and the pivoting element can preferably be designed so that a first part of the movement of the actuator leads to the pivoting movement, while the actuator is taken on further movement over the first part of addition in a transit area without the pivoting element performs a further pivoting movement ,

As a further advantage, the switching unit can be constructed very compact, in particular with a small overall depth in the retraction direction. This can be achieved particularly well when the actuating direction is arranged parallel to the retraction direction, and the switch actuating element is spaced transversely to the actuating direction of the receiving area. The parallel arrangement with a coupling via the shaft then allows a very short switching unit in the retraction direction.

As a particular advantage results in the switching unit according to the invention a good sealability, which is particularly advantageous for use as a safety switch. The selected for the implementation of the movement of the actuator in a movement of the switch operating element allow a good, in particular multi-stage seal. It is particularly advantageous in this context to provide a housing, having a plurality of separate and preferably closed to the outside chambers. According to the invention, the switching unit has a propulsion chamber for receiving the propulsion coupling. The propulsion chamber is separated from the necessarily open receiving area by a wall which is penetrated only by the shaft. In this case, already by appropriate fit a first sealing function can be realized, further sealing measures can be easily additionally provided on the shaft.

More preferably, a separate switch chamber may be provided for receiving the switch element. Also between the propulsion chamber and the switch chamber is preferably a chamber wall formed with an opening for the switch actuator. Here, too, a sealing function can already be achieved by appropriate fitting, preferably an additional sealing element is provided, for example as an O-ring or particularly preferably as a bellows.

Preferably, the pivoting member is formed so that the retraction of the actuator into the receiving area leads to a pivoting movement in a first pivoting direction, and that the extension of the actuator out of the receiving area leads to a pivoting movement in a second, opposite direction. For this purpose, according to an embodiment of the invention, the pivoting element have at least one first leg for contact with the actuator in the retraction direction, and a second leg for contact with the actuator during extension. In this case, a positive reception is particularly preferably given after the retraction of the actuator and the pivoting movement of the pivoting element, so that the retraction of the actuator inevitably leads to the pivoting movement in the second pivoting direction. In preferred embodiments, said legs may protrude radially from the shaft, wherein, for example, the first and the second leg are at an angle to each other, preferably at 90 °.

In a preferred embodiment, the actuator may have a shaft which extends, for example, rod-shaped in the retraction direction, and a head which is shaped differently from the shaft and in particular may preferably have at least one step for the positive reception. For example. For example, the head may be formed as a disk or a thickening at the end of the shaft, particularly preferably a T-shaped configuration. Preferably, the pivoting element is designed to cooperate with such an actuator with shaft and head, wherein, for example, a first leg of the pivoting element is deflectable through the head for bringing about the pivoting movement in the first pivoting direction. According to a preferred embodiment, the second leg has a fork, wherein the pivoting element is arranged so that during the pivoting movement in the first pivoting direction the shaft of the actuator is received in the fork, while the fork locks the head in a form-fitting manner. This type of positive recording ensures that an extension of the actuator necessarily always has a provision of the pivoting element result.

According to one embodiment of the invention, a return spring may be provided. In this case, preferably the pivoting movement in the first pivoting direction, d. H. when retracting the actuator, against the spring force of the return spring. Accordingly, the return spring acts on the pivoting element for returning to a starting position. As a result, it is first ensured that the pivoting element remains defined in a starting position without the inclusion of an actuator. In addition, can be supported by a return spring and the extension of the actuator, the pivotal movement of the pivot member in the second, opposite pivoting direction. In this case, the return spring can preferably be mounted so that it acts on the shaft. More preferably, the spring may be provided in the propulsion chamber. In particular, a leg spring comes into question to effect the restoring force.

By the Vortriebenkplung a pivoting of the shaft is converted into an adjustment of the switch operating element, preferably in the form of a linear, translational movement. According to a first embodiment, a propulsion coupling can be formed, for example by a toothed region (eg linear toothed area comparable to a toothed rack) on the switch actuating element and a propulsion element having a toothed circumference region (for example a toothed or partial toothed wheel) which is coupled to the shaft or even is integrally formed therewith. In this case, the toothed areas are in engagement with each other, so that a rotation of the driving element causes a linear movement of the switch actuating element.

In an alternative embodiment, the propulsion coupling comprises a driver fork and a cam engaged with the dog fork. In this case, for example, the driving fork may be coupled as a driving element with the shaft, while the cam received in the fork is part of the switch actuating element or at least coupled thereto. A rotation of the drive element then causes an adjustment of the switch actuating element, preferably in the form of a translational linear movement.

The switch element has according to a development of the invention at least two electrical contacts, which are arranged at a distance from each other. A contact bridge may be provided on the switch actuating element or coupled thereto, so that in a first position of the switch actuating element, the contact bridge at a distance from at least one, preferably two of the contacts is disposed, and in a second position of the switch actuating element, the contact bridge rests against both contacts and connects them electrically. In this case, the contact bridge, for example, be resilient, so that in the second position on the one hand by the spring action, the contacts for safe electrical contact are pressed together, and on the other hand always guaranteed a safe contact even with contact erosion over the life.

The switching unit thus preferably comprises a simple mechanical switch, for example in the form of a make or break contact. Thus, no additional electrical circuit or power supply is necessary. The switch position can be evaluated by direct connection, for example, in a series circuit of several switching units.

The switch assembly according to the invention comprises a switching unit and a relative to the switching unit movably arranged actuator. In this case, the actuator may have a shaft which comprises at least one flexible region. This allows by bending a recording of the actuator and safe triggering of the switching function, even in the case of larger mechanical tolerances.

In an exemplary application of the switch assembly, this is attached as a door contact so that when opening or closing a door, the actuator is received in the receiving area. So can be reliably detected by the electrical switching function, whether the door is in the respectively monitored open or closed position.

Fig. 1

in perspektivischer Darstellung eine Schaltbaugruppe mit geöffneter Schalteinheit;

Fig. 2

die Schaltbaugruppe aus Fig. 1 in Draufsicht;

Fig. 3

eine Ansicht eines Schnitts entlang der Linie A..A in Fig. 2;

Fig. 4a, 4b

in perspektivischer Darstellung isolierte Elemente der Schaltbaugruppe aus Fig. 1 - 3 in einer ersten und einer zweiten Schaltstellung;

Fig. 5

eine zweite Ausführungsform einer Schalteinheit in perspektivischer Darstellung;

Fig. 6

die Schalteinheit aus Fig. 5 in Draufsicht;

Fig. 7

eine Ansicht des Schnitts entlang der Linie B..B in Fig. 6;

Fig. 8

in schematischer Darstellung ein Sicherheitssystem für eine Tür und

Fig. 9

in perspektivischer Darstellung eine Ausführungsform eines Betätigers mit einem flexiblen Bereich.

Hereinafter, embodiments of the invention will be described in more detail with reference to drawings. Showing:

Fig. 1

a perspective view of a switch assembly with open switching unit;

Fig. 2

the switch assembly off Fig. 1 in plan view;

Fig. 3

a view of a section along the line A..A in Fig. 2 ;

Fig. 4a, 4b

in perspective view isolated elements of the switch assembly Fig. 1-3 in a first and a second switching position;

Fig. 5

a second embodiment of a switching unit in a perspective view;

Fig. 6

the switching unit off Fig. 5 in plan view;

Fig. 7

a view of the section along the line B. B in Fig. 6 ;

Fig. 8

a schematic representation of a security system for a door and

Fig. 9

in perspective view an embodiment of an actuator with a flexible area.

Hereinafter, embodiments of switching units and switching assemblies will be explained. These can be used in particular as door contacts of the security system for a door, in particular for an elevator door. A corresponding use is in Fig. 8 shown schematically. A switch assembly 12 is formed of a switch unit 10 and a separate actuator 14. The switch unit 10 is fixedly mounted to a stationary part 16 of a hoistway, while the actuator 14 is mounted on the door 18 movable with respect to the fixed part 16.

When closing the door 18, the actuator 14 moves into a receiving area 20 of the switching unit 10, which in the illustration of Fig. 8 is not visible, but will be explained in more detail below for various embodiments. By the inclusion of the actuator 14 in the receiving area 20 of the switching unit 10, the triggering of an electrical switch, in the preferred embodiment by closing a contact, which can be queried by the electrical connection 22 of the switching unit 10 takes place. When opening the door 18, the actuator 14 moves out of the receiving area 20 and the electrical contact within the switching unit 10 is opened again. In this way, by a suitable safety circuit for the elevator system (not shown), the closed state of the door 18 are monitored.

As a requirement of such a switch assembly, especially for elevator systems, a seal of the electrical switch is important in addition to a simple and compact design. Meaning this has, for example, that in case of fire, the elevator system should continue to function despite the use of extinguishing water.

Fig. 1-3 shows a first embodiment of the switch assembly 12 with the switching unit 10 and the actuator 14. Here, a part of a housing 24, namely a top cover and a part of the front side wall, not shown for better visibility.

The housing 24 encloses the switching unit 10 and has as openings only a sealed with a pinch seal passage 26 for the electrical connection 22 and in the front side wall an inlet opening 28 for the actuator 14. Inside, the housing 24 is divided into mutually separated by side walls 31,33, each closed chambers, namely a receiving chamber 30, a propulsion chamber 32 and a switch chamber 34th

The receiving area 20 for the actuator 14 is formed within the receiving chamber 30. Arranged therein is a pivoting element 36, the shape of which, in particular, can be seen from the illustrations in FIG Fig. 4a . Fig. 4b is clearly visible. The pivoting element 36 comprises, starting from a shaft 40, a first leg (receiving leg) 36a and a second leg (forked locking leg) 36b. The pivoting element 36 is formed integrally with the shaft 40 and can by its rotatable mounting in the housing 24 between a basic position ( Fig. 1-3 . 4a ) and a triggering position ( Fig. 4b ) are pivoted.

The shaft 40 extends through an opening in an inner partition wall 31 into the propulsion chamber 32. There, a switch actuating element 38 which can be displaced longitudinally in an actuating direction in a guide is arranged, which is coupled to the shaft 40 via a propulsion coupling 42. In the illustrated first embodiment, the propulsion coupling is 42 formed by an integrally formed on the shaft 40 Mitnehmergabel 44 and provided on the switch actuating element 38 cam 46 which is received in the Mitnehmergabel 44.

Further, a leg spring 60 is provided in the propulsion chamber 32. The leg spring 60 acts on the shaft 40 in such a way that it in the direction of Fig. 1, Fig. 2 . Fig. 4a illustrated basic position of the pivot member 36 is reset for receiving the actuator 14.

The switch actuating element 38 extends, in particular from the sectional view in FIG Fig. 3 can be seen, through an opening 48 in an inner partition wall 33 to the switch chamber 34. The opening 48 is sealed to the switch actuator 38 while a seal in the form of a bellows 50.

In the switch chamber is, as in particular from the perspective views Fig. 4a . Fig. 4b can be seen, an electrical switch element comprising two electrical contacts 52. On the switch actuator 38 is also in Fig. 4a . Fig. 4b illustrated contact bridge 54 arranged.

Within the switching unit 10 of the serves in Fig. 4a . Fig. 4b separately shown in two different switching states mechanism that when a recording of the actuator 14 in the receiving space 20 of the switch closed, so the electrical contact between the contacts 52 is made, while the retraction of the actuator 14 from the receiving space 20 of the switch is opened again. The mechanism for coupling the electrical switching function to the position of the actuator 14 includes, as shown, the pivot member 36, the shaft 40, the propulsion coupling 42, the switch actuator 38, and the switch element formed from the contact bridge 54 and the electrical contacts 52.

For this purpose, the actuator 14 at its longitudinally aligned shaft 56 has a T-shaped, transversely arranged head 58. In the in Fig. 4a shown basic position of the pivot member 36, the receiving leg 36a behind the inlet opening 28 is arranged so that the head 58 of the actuator presses against movement in the retraction direction against it, and so Pivoting element 36, and thus also the integrally formed therewith axis 40 and driving fork 44 against the force of the spring 60 is pivoted.

How out Fig. 1, Fig. 2 can be seen at the bottom of the receiving chamber 30 rails for guiding provided which are comb-like manner in the embodiment shown with the receiving leg 36a of the pivot member 36 so that retraction of the actuator 14 in the receiving area 20 is only possible if the pivot member 36 is pivoted ,

By the pivoting movement of the locking leg 36b locks the head 58 of the actuator 14 in the receiving area 20. For this purpose, the locking leg 36b is fork-shaped, wherein the shaft 56 of the actuator 14 as in Fig. 4b shown in the fork.

While already the first part of the retraction of the actuator 14 causes the pivoting movement of the pivot member 36 and thus the shaft 40, within the receiving chamber 30 sufficient space behind the pivot member 36 is present so that the actuator 14 can continue to retract (so-called Überfahrweg), without this has a further influence on the switching function.

The electrical switching function is triggered by the pivoting movement of the pivoting element 36, in that the switch actuating element 38 is moved further in the longitudinal direction (actuating direction) into the switch chamber 34 via the propulsion coupling 42, as shown in FIG Fig. 4b shown the contact bridge 54 rests against the contacts 52 and so makes the electrical contact. In this case, the contact bridge 54 is resilient and selected by the Vortriebenkplung 42 predetermined path accordingly, so that due to a certain deflection of the contact bridge 54, a resilient contact with the contacts 52 is given.

When extending the actuator 14 from the in Fig. 4b shown triggering the locking leg 36b, so that a pivoting movement of the pivot member 36 and the shaft 40 in the opposite direction, supported by the spring 60. By the Vortriebkopplung 42 is thereby the switch actuator 38 in its longitudinal direction in the normal position ( Fig. 4a ), so that the contact bridge 54 from the contacts 52 triggers and the electrical contact is interrupted.

Due to the positive reception of the head 38 in the fork-shaped locking leg 36 b, the separation of the electrical contact is inevitable, d. H. even in the case that the contact bridge should be welded to the contacts 52, the connection is disconnected by the forces during extension of the actuator 14 in each case.

In this case, the switching unit 10, as in particular Fig. 2 can be seen, a relatively small space in the retraction of the actuator 14, while still the above-mentioned Überfahrweg remains ensured. Because by the coupling by means of the shaft 40, which extends transversely to the retraction, in the illustrated embodiment, the longitudinally displaceable switch actuator 38 can be arranged with its actuating direction parallel to the retraction, but spaced from the receiving space 20.

The switching unit 10 is constructed so that the electrical switch element from the contacts 52 and the contact bridge 54 is completely sealed. The switch chamber 54 is completely closed off except for the sealed cable connection 26 and the opening 48 to the drive chamber 32. The opening 48 is sealed by the bellows 50 so that movement of the switch actuating element 38 in the longitudinal direction is possible without hindrance, but at the same time the seal is completely guaranteed. In this case, the propulsion chamber 32 is already separated from the open receiving chamber 30 by the inner dividing wall 31, which is penetrated only by the shaft 40, so that a multi-stage seal is achieved. Therefore, even when exposed to spray water from the outside, the sufficient sealing of the switch chamber 34 can be ensured.

In Fig. 5 to Fig. 7 a second embodiment of a switching unit 110 is shown. The switching unit 110 largely corresponds to the switching unit 10 according to the first embodiment described above. In the following, only the differences between the embodiments will be described in more detail, whereas in both embodiments, the same elements are marked with the same reference numerals.

In the second embodiment of the switching unit 110, the propulsion coupling 42 instead of as described above with a driving fork and a cam now executed by means of a gear member 144 formed integrally with the shaft 40 and a gear portion 146 disposed on the switch operating member 38. The gear member 144 in the illustrated embodiment is formed only as a partial gear having a gear portion extending only over a part of its circumference. This is possible due to the limited range of movement predetermined by the pivoting movement anyway. The gear portion of the gear member 144 is engaged with the linear gear portion 146 of the switch operating member 38 so that even in the second embodiment of a Vortriebskopplung 42, the pivotal movement of the pivot member 36 and the shaft 40 is converted into a linear displacement of the switch actuator member 38 in the longitudinal direction. Thus, in the second embodiment of the switching unit 110 in the same manner as described above, an operation of the electrical switch 52, 54, which is triggered by the inclusion of an actuator 14 in the receiving area 20, while the retraction of the actuator 14 from the receiving area 20 inevitably to a Separation of the electrical contact leads.

An advantage of the illustrated construction according to both embodiments is the low sensitivity to tolerances in the receiving area 20. As already described, a travel distance for the actuator 14 is ensured. Due to the positive reception of the actuator 14, the function is also ensured even with considerable tolerances in the transverse direction. Here, as in Fig. 9 shown an alternative embodiment of an actuator 114 are used, which has a flexible portion 62 in its shaft 56. While the actuator 14 is otherwise made in one piece, for example, from plastic, in the region 62 at least partially deviating from the rest of the shaft, more flexible material is used, so that the shaft can bend to be received in the receiving space 20.

The above embodiments are each to be understood as examples of possible implementations of the invention. Those skilled in the art will recognize that various changes are possible. While, for example, in the embodiments shown in each case the pivoting element 36, the shaft 40 and a part 44,144 of the Vortriebkupplung 42 are integrally formed, for example. Plastic, these elements can alternatively also be formed and assembled separately. Instead of sealing by means of the bellows 50, other forms of sealing are possible, for example by means of an O-ring. While described in the Embodiments of the passage of the shaft 40 through the partition wall 31 between the receiving chamber 30 and the propulsion chamber 42 is not provided with a separate sealing element, such can be additionally provided to improve the seal.

Finally, as shown, the illustrated switching unit can also be used as a door contact for other purposes in which a monitoring of the position of the actuator 14 relative to the switching unit 10, 10 should take place, for example as a machine switch.

Claims (14)

Switching unit with a receiving area (20) for receiving an actuator (14), a pivoting element (36) arranged in the receiving area (20) and designed to pivot in a direction of movement into the receiving area (20) during a translatory movement of the actuator (14), a switch actuating element (38) which is displaceable in an actuating direction for actuating an electrical switch element (52, 54), - wherein a propulsion chamber (32) is provided for receiving a propulsion coupling (42) in order to adjust the switch actuating element (38) in the actuation direction, - wherein the propulsion chamber (32) from the receiving area (20) is separated by a wall (31) which is penetrated by a shaft (40). - And wherein the propulsion coupling (42) with the pivoting element (36) via the shaft (40) is coupled, so that during the pivoting movement, an adjustment of the switch actuating element (38). Switching unit according to claim 1, wherein the actuation direction is parallel to the retraction direction, - Wherein the switch actuating element (38) is spaced transversely to the actuating direction of the receiving area (20). Switching unit according to one of the preceding claims, in which - The receiving area (20) and the pivoting element (36) are formed so that a first portion of a movement of the actuator (14) leads to the pivoting movement, - And that in a further movement of the actuator (14) is received in a transit space without the pivot member (36) performs a further pivoting movement. Switching unit according to one of the preceding claims, in which a switch chamber (34) is provided for receiving the switch element (52, 54), - Wherein the switch chamber (34) is completed. Switching unit according to claim 4, wherein - The switch chamber (34) with the propulsion chamber (34) through a passage (48) for the switch actuator (38) is connected, wherein a seal (50) is provided on the passage. Switching unit according to one of the preceding claims, in which - The pivot member (36) has a first leg (36 a) for receiving the actuator (14), - So that the retraction of the actuator (14) into the receiving area (20) leads to a pivoting movement in a first pivoting direction, - And a second leg (36b) for receiving the actuator (14), so that the extension of the actuator (14) from the receiving area (20) out leads to a pivoting movement in a second, opposite pivoting direction. Switching unit according to one of the preceding claims, in which - The pivoting element (36) for cooperation with an actuator (14) with a shaft (56) and a head (58) is formed, - wherein the first leg (36a) is deflectable by the head (58) for bringing about the pivoting movement, - And the second leg (36 b) has a fork, wherein the pivoting element (36) is arranged so that upon pivotal movement in the first direction of the shaft (36) of the actuator (14) is received in the fork so that the fork the head (38) locks. Switching unit according to one of the preceding claims, in which - A return spring (60) is provided, so that the pivoting movement takes place against the spring force. Switching unit according to one of the preceding claims, in which the switch actuating element (38) has a toothed region (146), and a driving element (144) coupled to the shaft (40) is provided with a gearing peripheral area, - Wherein the toothed portion (146) and the Verzahnungsumfangbereich are engaged with each other, so that a rotation of the driving element (144) causes an adjustment of the switch actuating element (38). Switching unit according to one of the preceding claims, in which - The propulsion coupling (42) has a driving fork (44) which is coupled to the shaft (40), - and the switch actuating element (38) has a cam (46) which is in engagement with the driving fork (44), - So that a pivoting of the driving fork (44) causes an adjustment of the switch actuating element (38). Switching unit according to one of the preceding claims, in which the switch element has two contacts (52), and a contact bridge (54) is coupled to the switch actuating element (38), - In a first position of the switch actuating element (38) the contact bridge (54) is arranged at a distance from at least one of the contacts, and in a second position of the switch actuating element (38), the contact bridge (54) against the contacts (52) and this connects electrically. Switch assembly with - A switching unit (10,110) according to any one of the preceding claims, - And an actuator (14), with respect to the switching unit (10,110) movable is arranged for receiving in the receiving area (20) of the switching unit (10, 110). A switch assembly according to claim 12, wherein - The actuator (114) has a shaft (56) which comprises at least one flexible portion (62). Security system for a door, in particular an elevator door, with at least one switch assembly (12) according to any one of claims 12, 13, - Wherein the switch assembly (12) is mounted as a door contact so that when opening or closing the door (18) of the actuator (14) in the receiving area (20) of the switching unit (10,110) is received.

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