EP3057118B1 - Switching mechanism, fire protection switch and system - Google Patents

Description

The invention relates to a switching mechanism for a fire protection switch for switching a coupled with the fire circuit breaker circuit breaker. Furthermore, the invention relates to a fire protection switch for detecting an arc fault, which has such a switching mechanism, and a system consisting of such a fire protection switch and a coupled with the fire circuit breaker.

In electrical installation technology, the term "fire protection switch" is understood to mean a protective device for protection against a fault current caused by an arcing fault. Such arc fault protection devices are used in low-voltage networks to protect the electrical installation technology from damage due to a fault current due to a fault arc and its thermal consequences - such as cable fires.

An arc fault can occur, for example, at a defective point of an electrical line, such as a loose cable clamp, or due to a cable break. If the arc occurs electrically in series with an electrical load, the normal operating current is usually not exceeded because it is limited by the consumer. For this reason, the arc is not detected by a conventional overcurrent protection device, such as a fuse or a circuit breaker. This is particularly problematic at high operating currents as well as existing for a long time arc fault, since in these cases, there is a risk of fire due to the associated with the arc high temperatures.

To determine whether an arc is present, the fire circuit breaker the voltage profile and the current waveform over time are measured and evaluated by means of digital signal processing. In particular, the current profile has in a fault arc characteristic, high-frequency components. When evaluating, however, it should be noted that regular fluctuations in the course of the current as well as harmonics or transient current curves that occur during normal operation, such as occur when a load is switched on, do not lead to faulty tripping of the fire protection switch. For this reason, fire circuit breakers have relatively complex algorithms for monitoring the electrical installation as well as for detecting possible arcing faults.

In the (English-language) specialist literature, such devices for detecting arcing faults are referred to as "Arc Fault Detection Device" (AFDD for short). In North America, where the so-called UL standard (Underwriters laboratories, standard with 110 V mains voltage) prevails, the term "Arc Fault Circuit Interrupter" (abbreviated AFCI) is common. In the United States, arc circuit breakers are even compulsory to detect, based on predetermined criteria, whether there may be an electric arc in a circuit. For this purpose, the arc protection switches used there have their own isolating contact, which is opened in the event of the presence of an arc. The principles used in these arc circuit breakers are disclosed, for example, in US patents US 5,729,145 such as US 6,031,699 described. US2010 / 0073113 A1 discloses a circuit breaker for a fire circuit breaker according to the preamble of claim 1. in most European countries, the IEC standard (International Electrotechnical Commission, standard with a mains voltage of 230 V) mandatory prescribe arc-proof circuit breakers are not mandatory. Electrical circuits in IEC technology have hitherto mostly been protected by means of fault current circuit breakers and miniature circuit breakers. However, protection against arcing faults is not feasible with the mentioned protective switching devices.

Nevertheless, in order to realize effective protection against arcing faults, additional circuit breakers against arcing faults, so-called fire protection switches, are also being used here in Germany. In contrast to the models available on the US market, however, these fire protection switches generally do not have their own isolating contacts, but are usually used as an independent module, the so-called AFD block, with a further protective device, for example a circuit breaker (so-called LS switch ) or a combined circuit breaker / residual current circuit breaker (so-called RCCB). This combination of the two devices then forms the AFDD circuit breaker. In low-voltage electrical installation technology, such protective switching devices - i. Miniature circuit breakers, residual current circuit breakers or combination devices such as FI / LS or AFDD - also known as "DIN rail mounted devices". This term is due to the fact that in an electrical distribution manifold often a plurality of such modular devices are arranged side by side "in a row".

When combining a fire protection switch with the other protection switching device, on the one hand, an electrical connection of the two devices is required to realize a common feed. For this purpose, the fire circuit breaker usually already electrical connection means which are led out of the housing of the fire circuit breaker to be electrically connected to the terminals of the further protection switching device. On the other hand, the fire protection switch also has a mechanical coupling with the further protective switching device to transmit a generated based on a detected fault current trip signal from the fire circuit breaker to the other protection device. When the fire circuit breaker is tripped, the tripping signal is consequently sent to the further protective switching device - For example, a circuit breaker or a combined line protection / residual current circuit breaker - transmitted, which then causes by opening its switch contacts an interruption of the monitored circuit.

The transmission of this trigger signal is usually mechanically realized: via a mechanical coupling device of the fire circuit breaker a rotary or linear motion is transmitted to a mechanical element of the further protective switching device, which then causes the triggering of a switching mechanism of the further protection switching device. As a result of the triggering of the switching mechanism, the isolating contacts of the further protective switching device are opened, whereby the electrical line to be monitored is interrupted.

It should be noted, however, that for a safe triggering of the further protection switching device on the one hand, a predefined minimum value for the rotary or linear movement of the coupling device is required to ensure safe triggering of the switching mechanism of the other protection device. On the other hand, a predefined maximum value of the rotational or linear movement must not be exceeded in order to avoid damage to the coupling device or the switching mechanism of the further protective switching device.

It is therefore an object of the present invention to improve the tripping accuracy of the switching mechanism of the fire circuit breaker and thus increase the tripping safety.

This object is achieved by the switch mechanism for a fire circuit breaker, by the fire circuit breaker for detecting a fault arc, which has such a switching mechanism, as well as by the system consisting of a fire protection switch and a circuit breaker coupled to the fire circuit breaker, according to the independent claims solved. Advantageous embodiments are the subject of the dependent claims.

The switching mechanism according to the invention for a fire protection switch for switching a further protective switching device which can be coupled to the fire protection switch has a triggering device, which in turn has a tripping coil and a tripping plunger movably mounted relative thereto. Furthermore, the switching mechanism has a coupling device for coupling the fire protection switch to the further protective switching device. The coupling device in turn has an actuator element and a control element, wherein the actuator element has a first operative connection with the release tappet and a second operative connection with the control element. The active compounds are designed such that when triggering the fire circuit breaker by means of the control a switching mechanism of the further protective switching device is actuated. In this case, the actuator element and the control element are coupled to one another in such a way that, on the one hand, the control is co-actuated in the case of an actuation of the actuator element caused by the actuation plunger, but, on the other hand, the control element can also be moved independently of the actuator element.

The switching mechanism according to the invention is intended for use in a fire safety switch, which - since he has no own isolating contacts - with another protective switching device, such as a circuit breaker or a combined line protection / residual current circuit breaker, can be coupled. In this way, the isolating contacts of the further protective switching device can be used to interrupt the electrical line to be monitored in the event of an arc fault. If an arc fault is detected, the tripping coil is energized, whereby the movably mounted trigger plunger is moved from its triggering position to a tripped position. This movement of the trigger plunger is then applied to the actuator element and on transfer the control. Trigger plunger, actuator element and control thus form a mechanical chain of action. In the coupled state of the fire circuit breaker with the further protective switching device, the control element is mechanically coupled to a switching mechanism of the further protective switching device such that the switching mechanism of the further protective switching device can be actuated by the movement of the control element. A caused by the switching mechanism of the further protection switching device movement of the control - for example, due to an overload, short circuit or residual current release of the further protection switching device - is, however, possible without repercussion on the actuator, ie the control is - at least in a first direction - independently of the actuator movable ,

In this way, movement of the control in a predefined area, i.e., initiation of the fire protection switch, is accomplished. between a predefined minimum range and a predefined maximum range, adjustable, without having to take into account a "movement initiated from the outside", for example by the switching mechanism of the coupled further protective switching device. Thus, on the one hand de tripping accuracy of the switching mechanism - and thus the fire circuit breaker - significantly improved. On the other hand, damage to the coupling device or the switching mechanism of the further protective switching device can thereby be avoided.

In an advantageous further connection of the switching mechanism, the actuator element and the control element are rotatably mounted about their respective axis of rotation.

Both the actuator element and the control element are rotatably mounted about an axis of rotation assigned to them. Thus, the linear movement of the trigger plunger is converted into a rotational movement of the actuator or the control element, which can then be transferred to the coupled, further protective switching device in a simple manner.

In a further advantageous connection of the switching mechanism, the axis of rotation of the actuator element and the axis of rotation of the control element are arranged concentrically.

Due to the concentric mounting of the actuator and the control element a very space-saving arrangement of the coupling device can be realized. The term "concentric bearing" is understood to mean that the axis of rotation of the actuator element is identical to the axis of rotation of the control, i. both elements are rotatable about the same axis.

In a further advantageous connection of the switching mechanism, an effective range of the trigger plunger interacts with an active contour of the actuator element to form a contact point. The active region is formed as a flat surface, whereas the active contour is formed spherical so that the contact point at each angular position of the actuator has the same distance from the axis of rotation.

The effective range of the release plunger, which cooperates with the active contour of the actuator element to form a contact point, is formed on the end face of the plunger as a flat, flat surface. The surface normal of the effective region is oriented substantially parallel to a direction of movement of the trigger plunger. By a corresponding rounded, convex design of the active contour is achieved that the contact point, ie the point of contact of the trigger plunger with the actuator, always, ie at each angular position of the actuator, the same distance from the axis of rotation of the actuator. This makes it possible, a uniform linear movement of the trigger plunger in an equally uniform rotational movement of the actuator convert. This would not be possible with a convex design of the effective range of the trigger plunger, which cooperates with a flat shaped active contour of the actuator, since in this case the distance of the contact point to the axis of rotation would not be constant, but would migrate towards the axis of rotation with increasing rotational angle. In this way, a predefined rotation angle range of the actuator element-and thus a predefined rotation angle range of the control element-can be set reliably in all tolerance positions.

In a further advantageous connection of the switching mechanism, a rotation angle range of the actuator element is limited in a first direction by a mechanical first stop.

By the mechanical stop, a maximum value of the rotational angle range of the actuator element is realized in a simple manner in the first direction. This will also cause a triggering - i. Initiated by triggering the fire circuit breaker - rotation angle of the control limited in a predefined manner, whereby overspeeding, and thus a possible damage, the control element in the event of tripping due to a detected fault arc is effectively avoided.

In a further advantageous connection of the switching mechanism of the rotation angle range is limited in a direction opposite to the first direction of the second direction by a mechanical second stop.

In this way, the rotational angle range of the actuator element is also limited in the opposite direction to the first direction, the second direction in a simple manner. This ensures that the actuator element is always in the same predefined position when the fire protection switch is ready to be triggered. The tripping accuracy of the switching mechanism is thereby further improved.

In a further advantageous connection of the switching mechanism, a rotation of the control element in the first direction beyond the first stop is possible.

If, due to a release of the coupled with the fire circuit breaker further protective switching device, in which via the switching mechanism of the further protection switching device, a rotary motion is transmitted to the coupled control of the fire circuit breaker, a larger angle of rotation is required, this is to the - beyond the first stop also freely movable - Control transferable without action. This means that the control element can be moved beyond the first stop "from the outside", without any corresponding movement of the actuator element being connected beyond the first stop. The control element is thus freely movable beyond the first stop in the first direction.

In a further advantageous further connection, the switching mechanism has a spring element, which pushes the control element back into its starting position.

With the aid of the spring element, which acts in the second direction, the control element can, after a movement in the first direction, for example due to a triggering of the fire protection switch, be returned to its initial position, i. in its trigger-ready state, reset.

In a further advantageous connection of the switching mechanism, the control has a driver, which moves along with the movement of the control element in its initial position, the actuator.

With the help of the driver formed on the control element, the actuator element also returns to its ready-to-trigger state reset. By this coupling of the restoring movements of the control element and the actuator element can be dispensed with a separate return spring for the actuator.

The fire protection switch according to the invention for detecting an arc fault has a housing, which in turn has a front side, a front side opposite mounting side, as well as the front side and the attachment side connecting connecting sides. Furthermore, the fire circuit breaker on a switching mechanism of the type described above, which is arranged in the housing and is provided for switching a coupled with the fire circuit breaker further protective switching device, wherein a coupling device of the switching mechanism of the fire protection switch is rotatably mounted in one of the connecting sides of the housing.

The storage of the coupling device in that connection side, which is arranged adjacent to the further protective switching device to be coupled, makes it possible to trigger a trigger mechanism of the coupled with the fire circuit breaker further protective switching device on triggering the fire circuit breaker via the control of the coupling device, via the isolating contacts arranged there To cause interruption of the electrical line to be monitored. With regard to the other advantages of the fire protection switch according to the invention, reference is made to the above statements on the advantages of the switching mechanism according to the invention.

In an advantageous further connection of the fire protection switch, the mechanical first stop and / or the mechanical second stop of the switching mechanism are formed as Anformung on the housing.

The design of the mechanical first and / or second stop as Gehäuseanformung provides a simple and inexpensive way to design the attacks.

The system according to the invention has a fire protection switch of the type described above and a further protective switching device coupled to the fire protection switch. The coupling of the fire circuit breaker with the further protective switching device is realized by a positive engagement of the control element in a movably mounted receiving element of the circuit breaker, so that when triggered the fire protection switch by pressing the recording coupled to the recording switching mechanism of the further protective switching device is actuated.

With regard to the advantages of the system according to the invention, reference is made to the above statements on the advantages of the switching mechanism according to the invention and the fire protection switch according to the invention.

Figuren 1A und 1B

schematische Darstellungen des Systems aus Brandschutzschalter und weiterem Schutzschaltgerät in verschiedenen Montagezuständen;

Figuren 2A und 2B

schematische Darstellungen der Schaltmechanik des Brandschutzschalters in verschiedenen Ansichten;

Figur 3

eine schematische Detaildarstellung des Zusammenwirkens des Auslösestößels mit dem Aktuatorelement;

Figuren 4A und 4B

schematische Darstellungen der Koppeleinrichtung der Schaltmechanik in verschiedenen Montagezuständen.

In the following, an embodiment of the switching mechanism, the fire circuit breaker and the system, consisting of a fire circuit breaker and coupled to the fire circuit breaker circuit breaker, with reference to the accompanying figures. In the figures are:

Figures 1A and 1B

schematic representations of the system consisting of fire protection switch and further protective switching device in various installation states;

FIGS. 2A and 2B

schematic representations of the switching mechanism of the fire circuit breaker in different views;

FIG. 3

a schematic detail of the interaction of the release plunger with the actuator element;

FIGS. 4A and 4B

schematic representations of the coupling device of the switching mechanism in different assembly states.

In the various figures of the drawing, like parts are always provided with the same reference numerals. The description applies to all drawing figures in which the corresponding part can also be recognized.

In the Figures 1A and 1B the system of fire protection switch 1 and further protection switching device 100 is shown schematically in various assembly states. Figure 1A in this case shows the fully assembled system in which the fire protection switch 1 to another protective switching device 100, which may be formed, for example, as a circuit breaker or as a combined line protection residual current circuit breaker coupled.

FIG. 1B schematically shows the two protection devices 1 and 100 in perspective view before the final assembly or coupling. The fire protection switch 1 in this case has a housing 2, which in turn has a front side 3, a front side 3 opposite mounting side 4, and the front and the mounting side 3 and 4 connecting connecting sides 5. The further protective switching device 100 also has a housing 102, which in turn has a front side 103, a front side 103 opposite mounting side 104, and the front and the attachment side 103 and 104 connecting connecting sides 105. For manual actuation, the further protective switching device 100 has an actuating element 106, which on the front side 103 of the housing 102 of the further protective switching device 100 is arranged.

The fire protection switch 1 also has a control element 22, which is rotatably mounted in the connecting side 5 of the fire protection switch 1 facing the further protective switching device 100. The control element 22 corresponds in this case with respect to its position with a receiving element 107, which is also rotatably mounted in the fire protection switch 1 facing the connecting side 105 of the further protective switching device 100. In the in Figure 1A shown coupled state of the two devices, the control 22 of the fire protection switch 1 engages positively in the receiving element 107 of the further protection switching device 100 to transmit a mechanical release signal to a switching mechanism of the further protection switching device 100 at a tripping of the fire protection switch 1.

In the FIGS. 2A and 2B the switching mechanism of the fire protection switch 1 is shown schematically in different views. The switching mechanism is received and held in the housing 2 of the fire protection switch 1 and has a triggering device 10, which in turn has a tripping coil 11 and a trigger plunger 12 movably mounted relative thereto. If the trip coil 11 is energized, for example due to a detected by the fire circuit breaker 1 arc, a magnetic field is generated, which is the trigger plunger 12 of the in the FIGS. 2A and 2B shown trigger ready position in a triggered position against an actuator 21 pulls. The actuator element 21 is part of a coupling device 20 (see FIGS. 4A and 4B ), which serves for coupling the fire protection switch 1 to the further protective switching device 100. The actuator element 21 forms, together with the control element 22 and the spring element 25, the coupling device 20. The actuator element 21 and the control element 22 are in one Connection side 5 of the housing 2 mounted coaxially or concentrically and thus have a common axis of rotation 24.

The actuator element 21 has a first operative connection with the trigger plunger 12, as well as a second operative connection with the control element 22. These active connections are designed in such a way that when the fire protection switch 1 is triggered, for example due to a detected arc fault, the release plunger 12 is pressed to the left against the actuator element 21, whereby the actuator element 21 is rotated clockwise about its axis of rotation 24. This rotation of the actuator 21 is limited by a mechanical first stop 6, which is integrally formed on the connecting side 5 of the housing 2. Via a driver 26, which is integrally formed on the control element 22, the rotational movement of the actuator 21 is transmitted to the control element 22, which is also rotated about the rotation axis 24 in the clockwise direction. Actuator element 21 and control element 22 are thus coupled to one another in such a way that, when the actuation element 21 is actuated by the actuation plunger 12, the control element 22 is co-actuated therewith.

By the first mechanical stop 6, however, only the rotational angle range of the actuator 21, but not that of the control element 22 is limited. As a result, the control element 22 is rotatable beyond the stop 6, independently of the actuator element 21. This is important if the control element 21 from the outside - for example via the receiving element 107 of the further protective switching device 100 (see FIG. 1B ) is caused to rotate whose rotational angle range exceeds that of the actuator element. In this way, damage to the receiving element 107, the control element 22 or the actuator 21 by the mechanical separation of the control element 22 and actuator 21 can be avoided. At the same time, when the fire protection switch is triggered, the maximum angle of rotation through the first mechanical Stop 6 predetermined. The rotation angle range of the control element 22 is thus limited to the maximum angle of rotation of the actuator element 21 when the movement of the actuator element 21 is initiated by a triggering of the fire protection switch 1.

FIG. 3 schematically shows a detailed representation of the interaction of the trigger plunger 12 with the actuator 21. On its - oriented toward the actuator 21 - - front side of the trigger plunger 12 has an effective range 13, which is designed as a flat, flat surface. Correspondingly, the actuator element 21 has an active contour 23, which is formed spherically (with an approximately semicircular cross-section). If the trigger plunger 12 in the event of triggering the fire circuit breaker 1 by energizing the trip coil 11 is moved from its triggering position to the left in its triggered position, so the effective range 13 of the trigger plunger 12 with the active contour 23 of the actuator 21 forms a contact point. When the actuator element 21 rotates about the axis of rotation 24, this contact point indeed moves on the active contour 23 of the actuator element 21 in the radial direction. The distance of the contact point to the axis of rotation 24 remains, however, always the same due to the spherical shape of the active contour 23 at each angular position of the actuator 21. In this way it is ensured that a uniform linear movement of the trigger plunger 12 is converted into a uniform rotational movement of the actuator 21.

In order to return the actuator element 21 to its predefined, trigger-ready position, the switching mechanism of the fire protection switch 1 has a mechanical second stop 7, which - as well as the mechanical first stop 6 - is formed as an molding on the housing 2 of the fire protection switch 1. By the mechanical first stop 6 and the mechanical second Anschlag7 are the maximum value and the minimum value of the rotation angle range of the actuator 21 clearly defined.

To reset the control element 22 in its - shown in Figures 2A and 2B, tripping ready position - the coupling device 20, a spring element 25 which applies spring force required for the provision. The spring element 25 is presently designed as a torsion spring (see also FIGS. 4A and 4B ). It has a first end 25-1, which is supported on a formed as a molding in the housing 2 Einhängezapfen 8. A second end 25-2 of the spring element 25 is mounted on the - also designed as a pin - driver 26 of the control element 22. If the spring element 25 is wound counterclockwise, a spring force generated thereby acts on the driver 26, whereby the control element 22 is urged in the counterclockwise direction in the direction of its triggering ready position. About the driver 26 while the actuator 21 is reset in its counter-clockwise back to its trigger ready position.

In the FIGS. 4A and 4B the coupling device 20 of the switching mechanism is shown schematically in different assembly states. FIG. 4A shows the coupling device 20 in mounted design, while in FIG. 4B a corresponding exploded view of the coupling device 20 is shown schematically. The coupling device 20 essentially consists of the actuator element 21, the control element 22 and the spring element 25. As part of the assembly of the coupling device 20, the actuator element 21 and the control element 22 are inserted concentrically into one another, so that both parts have the same axis of rotation 24. Between the actuator element 21 and the control element 22, the spring element 25 is mounted before nesting, with the second end 25.2 being suspended on the driver 26.

LIST OF REFERENCE NUMBERS

1

Fire protection switch

2

casing

3

front

4

mounting side

5

Links page

6

first stop

7

second stop

8th

Einhängezapfen

10

triggering device

11

trip coil

12

Actuation tappet

13

effective range

20

coupling device

21

actuator

22

control

23

active contour

24

axis of rotation

25

spring element

25-1

first end

25-2

second end

26

takeaway

100

another protective switching device

102

casing

103

front

104

mounting side

105

Links page

106

actuator

107

receiving element

Claims (12)

1. Switching mechanism for a fire protection switch (1) for switching a further protective switching device (100) which can be coupled to the fire protection switch (1), comprising

   - a tripping device (10) which has a tripping coil (11) and also a tripping plunger (12) which is movably mounted relative to the said tripping coil,

   - a coupling device (20) for coupling to the further protective switching device (100), which coupling device has an actuator element (21) and also a control element (22),

   - wherein the actuator element (21) has a first operative connection to the tripping plunger (12) and also a second operative connection to the control element (22) in such a way that, when the fire protection switch (1) is tripped, a switching mechanism of the further protective switching device (100) can be operated by means of the control element (22),

   wherein the actuator element (21) and the control element (22) are coupled to one another in such a way

   - that, when the actuator element (21) is operated in a manner prompted by the tripping plunger (12), the control element (22) is also operated, characterized in that the control element (22) can also be moved independently of the actuator element (21).
2. Switching mechanism according to Claim 1,
   wherein the actuator element (21) and the control element (22) are mounted such that they can rotate about their respective rotation axis (24).
3. Switching mechanism according to Claim 2,
   wherein the rotation axis (24) of the actuator element (21) and the rotation axis (24) of the control element (22) are arranged concentrically.
4. Switching mechanism according to either of Claims 2 and 3,

   - in which an operative region (13) of the tripping plunger (11) interacts with an operative contour (23) of the actuator element (21) so as to form a contact point,

   - wherein the operative region (13) is in the form of a planar surface,

   - wherein the operative contour (23) is of spherical design in such a way that the contact point at each angular position of the actuator element (21) is at the same distance from the rotation axis (24).
5. Switching mechanism according to one of Claims 2 to 4,
   wherein a rotation angle range of the actuator element (21) is limited by a mechanical first stop (6) in a first direction.
6. Switching mechanism according to Claim 5,
   wherein the rotation angle range is limited by a mechanical second stop (7) in a second direction which is opposite to the first direction.
7. Switching mechanism according to either of Claims 5 and 6,
   wherein rotation of the control element (22) is possible beyond the first stop (6) in the first direction.
8. Switching mechanism according to one of the preceding claims,
   comprising a spring element (25) which forces the control element (22) back to its starting position.
9. Switching mechanism according to Claim 8,
   wherein the control element (22) has a driver (26) which, when the control element (22) moves to its starting position, also moves the actuator element (21).
10. Fire protection switch (1) for detecting a fault,

    - comprising a housing (2) which has a front side (3), a fastening side (4) which is situated opposite the front side (3), and also connecting sides (5) which connect the front side (3) and the fastening side (4),

    - comprising a switching mechanism according to one of Claims 1 to 9, which switching mechanism is arranged in the housing (2) and is intended to switch a further protective switching device (100) which can be coupled to the fire protection switch (1),

    - wherein a coupling device (20) of the switching mechanism is rotatably mounted in one of the connecting sides (5) of the housing (2).
11. Fire protection switch (1) according to Claim 10,
    wherein the mechanical first stop (6) and/or the mechanical second stop (7) of the switching mechanism are in the form of integral formations on the housing (2).
12. System having a fire protection switch (1) and also a further protective switching device (100) which is coupled to the fire protection switch (1),

    - wherein the fire protection switch (1) is designed according to either of Claims 10 and 11,

    - wherein coupling of the fire protection switch (1) to the further protective switching device (100) is realized by positive engagement of the control element (22) into a movably mounted receiving element (107) of the further protective switching device (100),

    - so that, when the fire protection switch (1) is tripped, a switching mechanism of the further protective switching device (100), which switching mechanism is coupled to the receiving element (107), is operated by operation of the receiving element (107).

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