EMERGENCY-STOP SWITCH AND MACHINE WITH AN EMERGENCY-STOP SWITCH

Abstract

The invention relates to an emergency stop switch, having: a switch mechanism with a manually operable switch and with a first contact element which is operatively connected to the switch, wherein the switch is configured to bring the first contact element into contact with a second contact element to trigger an emergency stop function. A cable pull mechanism with a switch tongue guided in a switch tongue guide is connected to a first end of a cable, wherein a switch tongue spring preloads the switch tongue during operation in a direction away from the cable. The cable is connected on its second end with preload to an equalizing spring during operation, wherein the first contact element is operatively connected to the switch tongue. When the preloaded cable is pulled, is guided in the switch tongue guide in the direction of the cable, opposing a spring force of the switch tongue spring, and in the process brings the first contact element into contact with the second contact element in order to trigger the emergency stop function by the cable pull mechanism.

Claims

1. An emergency stop switch, comprising: a switch mechanism with a manually operable switch and with a first contact element which is operatively connected to the switch, wherein the switch is configured, upon actuation of the switch, to bring the first contact element into contact with a second contact element to trigger an emergency stop function, and a cable pull mechanism with a switch tongue guided in a switch tongue guide, wherein the switch tongue is configured to be connected to a first end of a cable, wherein a switch tongue spring preloads the switch tongue during operation in a direction away from the cable, wherein the cable is connected on its second end with preload to an equalizing spring during operation, wherein the first contact element is operatively connected to the switch tongue in such a way that the switch tongue, when the preloaded cable is pulled, is guided in the switch tongue guide in the direction of the cable, opposing a spring force of the switch tongue spring, and in the process brings the first contact element into contact with the second contact element in order to trigger the emergency stop function by means of the cable pull mechanism.

2. The emergency stop switch according to claim 1, characterized in that the first contact element and the switch tongue are operatively connected to each other by an actuator.

3. The emergency stop switch according to claim 2, characterized in that the actuator is designed configured as an idler wheel.

4. The emergency stop switch according to claim 2, characterized in that the actuator is arranged in a recess in the switch tongue.

5. The emergency stop switch according to claim 4, characterized in that the recess has two flanks running obliquely to a longitudinal axis of the switch tongue.

6. The emergency stop switch according to claim 4, characterized in that the recess is trapezoidal.

7. The emergency stop switch according to claim 1, characterized in that the switch tongue spring is preloaded.

8. The emergency stop switch according to claim 1, characterized in that the switch tongue spring is designed as a spiral spring which is arranged concentrically around the switch tongue.

9. The emergency stop switch according to claim 1, characterized in that the switch tongue guide is formed in a switch tongue housing, and the switch tongue housing has a contact portion against which the switch tongue spring is applied.

10. The emergency stop switch according to claim 1, characterized in that the switch tongue has a support portion on which the switch tongue spring is supported.

11. The emergency stop switch according to claim 1, characterized in that the switch tongue has a guide bolt guided in a longitudinal guide of the cable pull mechanism.

12. The emergency stop switch according to claim 1, characterized in that, during operation, the equalizing spring is firmly clamped in a clamp or is configured to be firmly clamped in a clamp.

13. The emergency stop switch according to claim 1, characterized in that a first axis along which the switch mechanism acts and a second axis along which the cable pull mechanism acts are transverse to each other.

14. The emergency stop switch according to claim 1, characterized in that the switch mechanism and the cable pull mechanism are arranged in a single housing of the emergency stop switch.

15. The emergency stop switch according to claim 1, characterized in that the switch tongue has a marking for adjusting a predetermined preload of the cable, the emergency stop switch having a viewing port for reading the marking.

16. A machine comprising an emergency stop switch having a switch mechanism with a manually operable switch and with a first contact element which is operatively connected to the switch, wherein the switch is configured, upon actuation of the switch, to bring the first contact element into contact with a second contact element to trigger an emergency stop function, and a cable pull mechanism with a switch tongue guided in a switch tongue guide, wherein the switch tongue-is configured to be connected to a first end of a cable, wherein a switch tongue spring preloads the switch tongue during operation in a direction away from the cable, wherein the cable is connected on its second end with preload to an equalizing spring during operation, wherein the first contact element is operatively connected to the switch tongue in such a way that the switch tongue, when the preloaded cable is pulled, is guided in the switch tongue guide in the direction of the cable, opposing a spring force of the switch tongue spring, and in the process brings the first contact element into contact with the second contact element in order to trigger the emergency stop function by means of the cable pull mechanism, wherein the second contact element is connected to the machine in such a way that triggering the emergency stop function by means of the emergency stop switch causes the machine to stop.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Further details and advantageous embodiments of the invention can be found in the following description, on the basis of which one embodiment of the invention will be described and explained in more detail, wherein:

[0036] FIG. 1 shows an embodiment of an emergency stop switch in a partially cutaway, perspective side view; and

[0037] FIG. 2 is a sectional view of a part of the emergency stop switch of FIG. 1.

DETAILED DESCRIPTION

[0038] The emergency stop switch 1 is in an operating mode in FIG. 1. The operating mode is a mode in which the emergency stop function is not triggered, and a machine equipped with the emergency stop switch 1 is being operated properly. In particular, it is supplied with current.

[0039] The emergency stop switch 1 has a housing 2. A switch mechanism 10 and a cable pull mechanism 20 are accommodated in the housing 2 of the emergency stop switch 1.

[0040] The switch mechanism 10 has a switch 11, which is designed as a mushroom button in the present exemplary embodiment. The switch 11 is rigidly connected to a first contact element 12 by means of a connecting part 13. In the present case, the first contact element 12 is designed as a round contact plate 12. The switch 11 can be actuated in the X.1 direction along the first X axis.

[0041] When the switch 11 is actuated due to an emergency, the connecting part 13 and the first contact element 12 are displaced in the direction X.1 along the first axis X. Due to the displacement of the contact plate 12, it comes into contact with a second contact element 14 of a switch unit 15, which is arranged on a side wall of the housing 2. This triggers an emergency stop function. For example, for a machine which is supplied with current, the power supply to the machine can be interrupted by executing the emergency stop function. This brings the machine to a standstill.

[0042] In order to deactivate the emergency stop function or to return to the operating mode, the switch 11 can be reset in the direction X.2 along the first X axis. This process releases the contact between the contact plate 12 and the second contact element 14, as a result of which the switch unit 15 enters the operating mode.

[0043] The cable pull mechanism 20 has a switch tongue 21 and a cable 30. The switch tongue 21 is connected to the first end of the cable 30 by means of a wire eye 29. Furthermore, the switch tongue 21 is guided in a switch tongue guide 22. In the present case, the switch tongue guide 22 is formed in a switch tongue housing 23. The switch tongue housing 23 encloses the switch tongue 21 in a portion close to the cable 30, and leaves the switch tongue 21 exposed in a portion remote from the cable 30.

[0044] A switch tongue spring 24 of the cable pull mechanism 20 is arranged concentrically around the switch tongue 21. The switch tongue spring 24 is supported against a support portion 25 of the switch tongue 21. In the present case, the switch tongue spring 24 is designed as a compression spring. In the present case, the support portion 25 is designed as a peripheral thickening of the switch tongue 21. Furthermore, the switch tongue spring 24 lies against a contact portion 26. In the present case, the contact portion 26 is formed in a switch tongue housing 23.

[0045] The cable 30 is also connected to an equalizing spring 31 at its second end. The equalizing spring 31 is clamped in a fixed clamp 32. The equalizing spring 31 preloads the cable 30. When the cable 30 is preloaded, the switch tongue spring 24 is compressed between the support portion 25 and the contact portion 26, and is thus preloaded.

[0046] The switch tongue 21 also has a trapezoidal recess 27 with two flanks F.1, F.2 (see FIG. 2). The cable pull mechanism 20 has an actuator 28 arranged in the trapezoidal recess 27 in the operating mode. The actuator 28 is mounted in a manner allowing sliding along the second Y axis. In the present case, the actuator 28 is designed as an idler wheel 28. In the present case, the idler wheel 28 is mounted on the connecting part 13 of the switch mechanism 10. A longitudinal center axis of the idler wheel 28, designed as an axis of rotation, coincides with the first axis X of the switch mechanism 10.

[0047] If the cable 30 is now pulled in any direction along the first axis X, the second axis Y or the third axis Z, which are orthogonal to each other, when the emergency stop switch 1 is in the operating mode, the switch tongue 21 is pulled along its switch tongue guide 22 in the direction Y.2 along the second axis Y, and against the spring resistance of the preloaded switch tongue spring 24. As a result, the switch tongue 21 is displaced in the direction Y.2 in relation to the idler wheel 28 and the contact plate 12. The trapezoidal recess 27 with the switch tongue 21 migrates opposite the idler wheel 28 in direction Y.2 along the second axis Y. Accordingly, the idler wheel 28 rolls up the first flank F.1 of the trapezoidal recess 27 near the free end of the switch tongue 21, and thus moves in direction X.1 along the first axis X. The idler wheel 28 also rolls on the contact plate 12 and presses it in the direction of the second contact element 14 until the contact plate 12 and the second contact element 14 contact each other. As a result, the emergency stop function is triggered by means of the cable pull mechanism 20.

[0048] If the cable 30 is now released by the operator who pulled it, the shifting tongue spring 24, which is further preloaded against the spring resistance, pushes the shifting tongue 21 back in direction Y.1 along the second axis Y until the idler wheel 28 move on the first flank F.1 and in the direction X.2 along the first axis X, to once again arrive in the center of the recess 27. The cable 30, which is again tensioned by means of the equalizing spring 31, prevents the idler wheel 28 from also moving in the direction Y.2 along the second axis Y, also over the second incline. The contact plate 12 remains on the second contact element 14, such that, despite the cable being released, the operating mode does not begin, because the idler wheel 28 is not firmly connected to the contact plate 12, and merely makes contact with it when the emergency stop function is triggered.

[0049] In order to deactivate the emergency stop function or to return to the operating mode, the switch 11 must also be reset in the direction X.2 along the first X axis. This process releases the contact between the contact plate 12 and the second contact element 14, as a result of which the switch unit 15 enters the operating mode.

[0050] In addition to triggering the emergency stop function by actuating the switch 11 and pulling the cable 30, the emergency stop switch 1 has a third option for triggering the emergency stop function. This third option is a breakage of the cable 30. The emergency stop function is activated for safety reasons in this case.

[0051] If the cable 30 breaks, the preload of the cable 30 by means of the equalizing spring 31 on the switch tongue 21 is no longer applied. As a result, the preloaded shifting tongue spring 24 is completely released, such that this preload is also released, and the shifting tongue spring 24 returns the shifting tongue 21 completely in the direction Y.1 along the second axis Y. The idler wheel 28 rolls up the second flank F.2 (see FIG. 2) of the trapezoidal recess 27 and presses the contact plate 12 against the second contact element 14, as a result of which the emergency stop function is triggered.

[0052] Then the idler wheel 28 is located in the direction Y.2 along the second axis Y behind the trapezoidal recess 27 and between the switch tongue 21 and the contact plate 12. Unlike when the cable 30 is pulled, the idler wheel 28 does not return to the recess 27 after the cable 30 has been released, since no preload is available by means of the cable 30 to accomplish this, which preload would guide the switch tongue 21 in the direction Y.2 along the second axis Y. Furthermore, the switch tongue spring 24 would also have to be overcome in order to bring the recess 27 in front of the idler wheel 28. The idler wheel 28 thus blocks the mushroom button 11 from being pulled back. For safety reasons, this prevents the emergency stop switch 1 from being unblocked if the cable 30 breaks. The broken cable 30 must be replaced in order to make the emergency stop switch 1 operational again, so that it can be put into the operating mode.

[0053] As FIG. 2 shows in the view of a longitudinal section through the switch tongue 21 together with the switch tongue housing 23 of the emergency stop switch 1 from FIG. 1, the switch tongue 21 in the present case is designed as an actuating bolt which is guided in the switch tongue guide 22 in the switch tongue housing 23. At its end opposite the trapezoidal recess 27, the switch tongue 21 is connected to the wire eye 29 for the connection to the cable 30 (see FIG. 1).

[0054] The trapezoidal recess 27 has the first flank F.1 and the second flank F.2, which are formed on the same side of the switch tongue 21. The flanks F.1, F.2 are formed obliquely in opposite directions relative to a longitudinal axis L of the switch tongue 21. Between the flanks F.1, F.2, there is a central portion of the recess 27 which is straight in the present case, and in which the idler wheel 28 is situated when the cable 30 is not pulled and has not broken.

[0055] Furthermore, the switch tongue housing 23 is formed from a first switch tongue housing part 23.1 and a second switch tongue housing part 23.2. The switch tongue 21 is fixed in the wire eye 29 near the second switch tongue housing part 23.2 by means of a locking pin 33. The first switch tongue housing part 23.1 is close to the trapezoidal recess 27, and comprises the switch tongue spring 24. The fixing of the switch tongue 21 by means of the locking pin 21 causes the second switch tongue housing part 23.2 to be moved away from the first switch tongue housing part 23.1 when the cable 30 is pulled. As a result, the switch tongue 21 can be moved along the second Y axis.

[0056] A bellows 35 is arranged between the switch tongue housing parts 23.1, 23.2, which bellows can expand and contract to follow the movement of the switch tongue 21 and to provide a seal against escaping oil from a plain bearing 34 and the switch tongue guide 22. The plain bearing 34 is formed in the present case in the first switch tongue housing part 23.1, and enables the switch tongue 21 to slide in the switch tongue guide 22.

[0057] In addition, the switch tongue 21 coaxially surrounded by the switch tongue spring 24 designed as a compression spring is provided with a sleeve 36, and is supported against the support portion 25 by means of a spring plate 37. The support portion 38 has a guide pin 38. The guide pin 38 extends in a direction Z.2 along the third axis Z. The guide pin 38 is guided in a longitudinal guide of the switch tongue housing 23, as is partially visible in FIG. 1. In the present case, the longitudinal guide is designed as an elongated recess in the switch tongue housing 23, in particular in the first switch tongue housing part 23.1. This prevents rotation of the switch tongue 21 and the cable 30.

[0058] Furthermore, the switch tongue housing 23 has a viewing port 40 for reading a marking 21 arranged on the switch tongue 21. The marking 21 is arranged at a position along the switch tongue 21 such that, when the marking 21 is in the center of the viewing hole 40, a predetermined preload of the cable 30 is set.