SAFETY SWITCH ARRANGEMENT

Description

[0001] The invention relates to a safety switch arrangement.

[0002] Such a safety switch assembly comprises a safety switch and an actuator, whereby this safety switch assembly is used in the field of safety technology. For use in the field of safety technology, particularly in the field of personal protection, it is necessary that the safety switch assembly meets normative requirements regarding its fail-safety, thus ensuring that the safety switch assembly can perform a correspondingly safe monitoring function. Such a safety switch assembly can typically be used to secure access to a hazardous area. For example, a safety switch assembly can be used to secure the locking of a separating protective device such as a safety door as access to a hazardous area.In this case, for example, the operation of a hazardous system within the danger zone is only enabled if the safety door is locked by the safety switch assembly. The system can be enabled via a safety controller, which receives safety-relevant switching signals from the safety switch assembly.

[0003] To lock the safety door, the actuator, in the form of a latch or similar device, is brought into engagement with the safety switch when the safety door is in its closed position. The actuator is retracted into a locking position on the safety switch, for example, by retracting it into a recess in the safety switch. This locking is controlled by an RFID reader in the safety switch detecting a transponder in the actuator.

[0004] In addition to this locking mechanism, a guard locking device can be provided for the safety door. Such a guard locking device is known, for example, from WO 2016 / 058718 A1. This guard locking device features a locking pin, which is actuated by an electric motor with a planetary gear. The electric drive can move the locking pin into a locked position, in which the actuator is locked by the locking pin.

[0005] EP 3 474 303 A1 relates to an actuator for a safety switch with an actuator head mounted on a base body by means of a connecting element. The actuator head has, at least in some sections, a larger cross-section than the connecting element. The connecting element is rigid in the axial direction. The actuator head is held in a basic position by the connecting element, in which the longitudinal axis of the connecting element extends at an angle of inclination to the surface of the base body.

[0006] The actuator can be deflected transversely to its longitudinal axis. This allows automatic alignment with a locking unit provided in the safety switch.

[0007] One problem with such a safety switch arrangement is that the deflection of the actuator changes the position of the transponder relative to the RFID reader, which can result in the transponder no longer being within the reading range of the RFID reader when the actuator is in the locked position. The locking of the actuator can then no longer be controlled by reading signals from the transponder.

[0008] US 5,744,767 A relates to a radius actuator for safety switches, consisting of a holder and an actuating bracket held therein, movable against spring force between an inclined approach position and a switch actuation position. The actuating bracket is attached to one end of a support member, the other end of which extends into the holder. The actuating bracket can be pivoted relative to the support member about a pivot axis and can be secured in any possible pivot position relative to the support member. The support member is attached to a base plate with its end extending into the holder and can be pivoted relative to this base plate about a second pivot axis and can be secured in any possible pivot position relative to the base plate.

[0009] DE 197 35 859 A1 relates to a locking device, in particular a safety locking device, comprising an opening closable by a dust cover for inserting or withdrawing an actuator, which in turn interacts within the device along a displacement path with, in particular, a plunger that actuates a switch and / or a locking element. To effectively prevent contamination of the interior of the device, it is proposed that the dust cover be a closure element that is subjected to force in the direction of the displacement path of the actuator and tightly or substantially tightly closes the opening when the actuator is withdrawn.

[0010] US 2013 / 0020817 A1 relates to a locking device with a guard locking mechanism for safety doors, comprising a door part for attachment to a movable safety door and a frame part for attachment to a door counterpart. The frame part has a receptacle and the door part has an actuator that can be fed into the receptacle. The frame part further has a locking member that can be displaced between a release position, in which the actuator can be selectively released, and a blocking position, in which the actuator can be selectively secured relative to the receptacle. The actuator is received on the door part via an elastic compensating element.

[0011] US 2019 / 0112838 A1 relates to an actuator for a safety switch with an actuator head mounted on a base body by means of a connecting element. The actuator head has, at least in some sections, a larger cross-section than the connecting element. The connecting element is rigid in the axial direction. The actuator head is held in a home position by the connecting element. In this home position, the longitudinal axis of the connecting element runs at an angle to the surface of the base body.

[0012] DE 101 57 157 A1 relates to an actuator for a locking device—with and without a guard locking mechanism—with a housing having an insertion opening for the actuator. The actuator is held by a spring-loaded plate-shaped holder, which in turn is releasably connected to a profile having a groove, for example, via a sliding block located within the groove, which in turn is a section of an area to be secured or is connected to it. In order to be able to design the actuator with a low overall height without compromising functionality, it is proposed that the actuator extend in sections within the groove of the profile.

[0013] The invention is based on the object of providing a safety switch arrangement of the type mentioned above which enables a reliable safety function.

[0014] To achieve this object, the features of claim 1 are provided. Advantageous embodiments and expedient developments of the invention are described in the dependent claims.

[0015] The invention relates to a safety switch arrangement comprising a safety switch having a reading unit and an actuator comprising a transponder and a movably mounted actuating element. The reading unit reads signals from the transponder when the transponder is within a reading range of the reading unit. The actuating element is connected to the transponder via a mechanical coupling means, so that a movement of the actuating element is transmitted to the transponder, so that in a locked position of the actuating element, the transponder lies within the reading range of the reading unit.

[0016] The safety switch assembly according to the invention is used in the field of safety technology, particularly for securing hazardous systems. In particular, the safety switch assembly can be used to secure access to a hazardous area of ​​a system, whereby access can be secured with a separating protective device such as a safety door.

[0017] The safety switch generates a release signal, particularly for the system, when the actuator's actuating element is in its locked position on the safety switch and when the transponder is within the reading range of the safety switch's reading unit. Data can then be read from the transponder using the reading unit, which allows the release signal to be generated.

[0018] The safety switch and actuator are mounted on different parts of the system. If the safety switch assembly is used to monitor a hazardous area, the actuator can be mounted on a movable guard such as a safety door, whereas the safety switch can be mounted stationary on a frame part or the like.

[0019] To release the system, the actuating element is retracted into a locking position on the safety switch. For example, the safety switch may have a recessed receptacle into which the actuating element is inserted in its locking position.

[0020] Due to assembly tolerances, the safety switch cannot be precisely aligned with the actuator. To ensure that the actuating element can still be moved into its locked position, it is movably mounted within or on the actuator. This allows the actuating element to perform compensating movements so that it can be moved into the locked position, particularly into the safety switch's receptacle.

[0021] According to the invention, the actuating element of the actuator is connected to the transponder of the actuator via a mechanical coupling means, so that a movement of the actuating element is transmitted to the transponder, i.e. the transponder carries out a movement that is the same as or corresponding to the movement of the actuating element.

[0022] This motion coupling ensures that, even in the event of a compensating movement of the actuating element, the transponder remains within the reading range of the reading unit when the actuator is in the locked position. Misalignments of the transponder relative to the reading unit during compensating movements of the actuating element are thus prevented by the motion coupling of the transponder and the actuating element using the mechanical coupling means.

[0023] This ensures that when the locking position is achieved, data from the transponder can be read by the reading unit, regardless of compensating movements of the actuating element, and the release signal is generated based on this. This ensures a high level of functional reliability of the safety switch arrangement according to the invention.

[0024] According to an advantageous embodiment, the coupling means forms a rigid connection between the transponder and the actuating element.

[0025] Advantageously, the transponder and the actuating element are firmly connected to the coupling means.

[0026] This means that a movement of the actuating element is transferred directly and immediately to the transponder by means of the coupling means, i.e. the transponder carries out the same movement as the actuating element through the coupling means.

[0027] According to a structurally advantageous embodiment, the actuator has a base body in which the coupling means is mounted in a positionally adjustable manner.

[0028] In particular, the coupling means with the transponder and the actuating element is mounted so that it can be moved and tilted.

[0029] This allows the actuating element to perform two different compensating movements. This allows for particularly effective compensation of misalignments between the safety switch and the actuator, ensuring the actuating element is safely moved into the locked position.

[0030] Advantageously, a recess is provided in a wall of the base body through which the actuating element is guided, wherein the actuating element is guided with play in the recess.

[0031] The clearance of the actuating element in the recess determines the range of motion for its compensating movements, meaning the recess limits the compensating movements. The size of the recess allows for application-specific dimensioning of the compensating movements. In particular, the sliding movement of the coupling element is limited by the size of the recess.

[0032] Advantageously, the coupling agent is mounted on springs in the base body.

[0033] The coupling agent can be tilted against the spring forces of the springs.

[0034] The tilt angle range of the actuating element can be specified by dimensioning the springs and their installation position in the base body relative to the coupling means.

[0035] In particular, the base body has two opposing walls spaced apart from each other. The recess is provided in a first wall, and the springs are mounted on the inside of a second wall.

[0036] The tilt angle range of the actuating element can then be specified by the distances between the walls in conjunction with the position of the coupling means and the springs.

[0037] According to an advantageous embodiment, the transponder is mounted in a section protruding beyond the base body.

[0038] This means that the base body does not interfere with the reading of data from the transponder. This is especially true if the base body is made of a metallic material. A base body extending into the reading area would make it impossible to read data from the transponder.

[0039] According to a first advantageous embodiment, the coupling means is formed by a plastic part.

[0040] This means that the transponder is also stored in a segment of the coupling agent made of plastic, which does not hinder, or does not significantly hinder, the reading of data from the transponder.

[0041] In this case, the coupling agent can be designed in the form of a plastic injection-molded part, which can be efficiently manufactured in freely definable shapes.

[0042] According to a second advantageous embodiment, the coupling means is formed by a sheet metal part.

[0043] The sheet metal part is in particular a stamped sheet metal part, which has a simple construction and can be manufactured cost-effectively.

[0044] In this case, the part of the sheet metal component that protrudes beyond the base body forms a recess designed to accommodate a plastic element. The transponder is located in the area of ​​the plastic element.

[0045] The sheet metal part, made of a metallic material, would hinder the reading of data from the transponder by the reading unit if it were to surround the transponder. This problem is solved by the plastic element mounted in the sheet metal part and surrounding the transponder, as this does not hinder the reading of data from the transponder.

[0046] The invention is explained below with reference to the drawings. They show: Figure 1: Schematic representation of the safety switch arrangement according to the invention with an actuator arranged remotely from a safety switch. Figure 2: Safety switch arrangement according to Figure 1 with the actuator in a locked position on the safety switch. Figure 3: First embodiment of the actuator according to the invention. Figure 4: Second embodiment of the actuator according to the invention.

[0047] The Figures 1 and 2 show schematically an embodiment of the safety switch arrangement 1 according to the invention with a safety switch 2 and an actuator 3. The safety switch arrangement 1 ensures safe operation of a system.

[0048] This safety switch assembly 1 is used, for example, to secure a safety door as access to a hazardous area. The actuator 3 can be located on the safety door, and the safety switch 2 can be arranged on a frame defining a door opening, whereby the door opening can be closed with the safety door.

[0049] The components of the safety switch 2 are integrated in a housing 4. In addition to a preferably two-channel processor structure (not shown), a reading unit 5 in the form of an RFID reader is integrated in the housing 4.

[0050] In the housing 4 there is a receptacle 6 in the form of a cavity which opens out at a side wall of the housing 4.

[0051] A transponder 7 is integrated into the actuator 3. Furthermore, the actuator 8 has an actuating element 9 protruding from a base body 8.

[0052] Figure 1shows the safety switch assembly 1 with the protective door open. Consequently, the actuator 3 is far away from the safety switch assembly 1.

[0053] Figure 2 shows the safety switch assembly 1 with the protective door closed. The actuator 3 is located close to the safety switch 2. The actuating element 9 is then retracted into its locking position, in which the actuating element 9 protrudes into the receptacle 6 of the safety switch 2. The safety switch 2 can have a guard locking device that mechanically locks the actuating element 9 in the locking position and secures it against detachment from the receptacle 6. Such a guard locking device has a suitable guard locking element (not shown) that can be moved by means of drive means.

[0054] If the actuating element 9 is positioned as in Figure 2Shown in its locked position, the transponder 7 of the actuator 3 lies within the reading range of the reading unit 5. Thus, data in the form of electromagnetic signals is read from the transponder 7 by the reading unit 5. Depending on this, the safety switch 2 generates an enable signal, which enables the operation of the system.

[0055] The safety switch arrangement 1 thus fulfills a safety function such that the operation of the system is only released when the protective door is closed.

[0056] Figure 3 shows a first embodiment of the actuator 3 according to the invention. The actuator 3 has a base body with two parallel walls 10, 11 spaced from each other, which form the top and bottom of an actuator housing.

[0057] The walls 10, 11 are connected by two tubular, hollow-cylindrical guide elements 12. Fasteners such as screws can be guided in these guide elements 12, with which the actuator 3, 8 can be attached to an object such as a safety gate.

[0058] On the inside of the second wall 11 forming a base, springs 13 are mounted which surround the guide segments 12.

[0059] A mechanical coupling element 14 is movably mounted on the springs 13. The coupling element 14 is movable in a plane parallel to the planes of the walls 10, 11. In this case, the coupling element 14 consists of a plastic part. The largest part of the coupling element 14 lies between the walls 10, 11.

[0060] The coupling means 14 forms a rigid, mechanical connection between the transponder 7 and the actuating element 9 of the actuator 3, 8. The transponder 7 (of which Figure 3 only the coil is shown) and the actuating element 9 are firmly connected to the coupling means 14. As can be seen from Figure 3 As can be seen, the transponder 7 is mounted on a section of the coupling means 14 that projects laterally beyond the base body 8a.

[0061] The longitudinal axis of the actuating element 9 runs perpendicular to the plane of the coupling means 14. In the present case, the actuating element 9 consists of a cylindrical shaft 15 and a head part 16 at the free end of the shaft 15, which is wider than the shaft 15.

[0062] When the actuating element 9 is retracted into its locking position in the receptacle 6 of the safety switch 2, a locking element can rest against or enclose the shaft 15 in a locked position. Since the head part 16 is wider than the shaft 15, the actuating element 9 is secured against detachment from the receptacle 6 by this locking element.

[0063] The actuating element 9 passes through a recess 17 in the wall 10 forming the upper side of the base body 8a, with the shaft 15 of the actuating element 9 located in the region of the recess 17. The diameter of the recess 17 is significantly larger than the diameter of the shaft 15, so that the actuating element 9 is guided in the recess 17 with play.

[0064] In order to compensate for existing assembly tolerances of the safety switch 2 and the actuator 3, the coupling means 14 and thus also the actuating element 9 can perform compensating movements.

[0065] On the one hand, the coupling means 14 can perform a displacement movement which is limited by the size of the recess 17, i.e. the coupling means 14 can be displaced until the shaft 15 of the actuating element 9 rests against the edge of the recess 17.

[0066] In addition, the coupling means 14 can perform a tilting movement in which the coupling means 14 is pressed downwards against the spring force of at least one spring 13.

[0067] These compensating movements of the coupling means 14 are transmitted directly and in the same way to the actuating element 9 and the transponder 7.

[0068] If, consequently, a compensating movement of the actuating element 9 is effected in order to insert it into the recess 17 of the safety switch 2, the transponder 7 is moved in the same way via the coupling means 14. This ensures that, even during compensating movements, the actuating element 9 of the transponder 7 of the actuator 3 is always within the reading range of the reading unit 5 when the actuating element 9 is retracted into its locked position in the receptacle 6 of the safety switch 2. This ensures that, in the locked position of the actuating element 9, data from the transponder 7 can be read by the reading unit 5, which is a prerequisite for generating an enable signal.

[0069] Since the transponder 7 is mounted in a section of the coupling means 14 that protrudes beyond the base body 8a, the base body 8a does not hinder the reading of the data from the transponder 7.

[0070] Figure 4 shows a second embodiment of the actuator 3 according to the invention. The embodiment according to Figure 4 differs from the embodiment according to Figure 3 essentially only with regard to the design of the coupling means 14 and the adjoining actuating element 9. Otherwise, the actuator 3 corresponds to Figure 4 regarding the construction and functioning of the embodiment according to Figure 3 .

[0071] The coupling means 14 in the actuator 3 according to Figure 4 from a stamped sheet metal part. The transponder 7 is mounted on a section of the coupling means 14 that protrudes laterally beyond the base body 8. This forms a recess in which a plastic element 18 is mounted. The transponder 7 is mounted in the area of ​​the plastic element 18, so that reading data is not hindered by the metallic stamped sheet metal part of the coupling means 14.

[0072] The actuating element 9, which is formed in one piece with the coupling means 14, consists of two parallel actuating element segments 19a, 19b, which are connected at their upper ends via an arc segment 20 of the sheet metal stamping.

[0073] There are holes 21 in the actuator element segments 19a, 19b. If the actuating element 9 is retracted into its locking position in the holder 6 of the safety switch 2, a locking element can be guided through these holes 21. List of reference symbols

[0074] (1)Safety switch assembly (2)Safety switch (3)Actuator (4)Housing (5)Reading unit (6)Receptacle (7)Transponder (8)Base body (9)Actuating element (10)First wall (11)Second wall (12)Guide element (13)Spring (14)Coupling means (15)Shaft (16)Head part (17)Recess (18)Plastic element (19a)Actuating element segment (19b)Actuating element segment (20)Arc segment (21)Bore

Claims

1. Safety circuit system (1) with a safety switch (2) having a reading unit (5) and an actuator (3, 8) which has a transponder (7) and a movably mounted actuating element (9), wherein signals are read from the transponder (7) by the reading unit (5) reads signals from the transponder (7) when the transponder (7) is located within a reading range of the reading unit (5), characterised in that the actuating element (9) is connected to the transponder (7) via a mechanical coupling means (14) of the actuator, so that a movement of the actuating element (9) is transmitted to the transponder (7), so that in a locking position of the actuating element (9), the transponder (7) is located within the reading range of the reading unit (5).

2. Safety circuit system (1) according to claim 1, characterised in that the coupling means (14) forms a rigid connection between the transponder (7) and the actuating element (9).

3. Safety circuit system (1) according to one of claims 1 or 2, characterised in that the transponder (7) and the actuating element (9) are fixedly connected to the coupling means (14).

4. Safety circuit system (1) according to one of claims 1-3, characterised in that, in the locked position, the actuating element (9) is retracted into a receptacle (6) of the safety switch (2).

5. Safety circuit system (1) according to one of claims 1-4, characterised in that the actuator (3, 8) has a base body (8a) in which the coupling means (14) is mounted in a positionally adjustable manner.

6. Safety circuit system (1) according to claim 5, characterised in that a recess (17) is provided in a wall (10, 11) of the base body (8a), through which the actuating element (9) is guided, wherein the actuating element (9) is guided with play in the recess (17).

7. Safety circuit system (1) according to one of claims 5 or 6, characterised in that the coupling means (14) is mounted so as to be displaceable and tiltable with the transponder (7) and the actuating element (9).

8. Safety circuit system (1) according to claims 6 and 7, characterised in that the displacement movement of the coupling means (14) is limited by the size of the recess (17).

9. Safety circuit system (1) according to any of claims 5-8, characterised in that the coupling means (14) is mounted on springs (13) in the base body (8a).

10. Safety circuit system (1) according to claim 9, characterised in that the coupling means (14) can be tilted against the spring forces of the springs (13).

11. Safety circuit system (1) according to one of claims 9-10. characterised in that the base body (8a) has two opposite walls (10, 11) extending at a distance from each other, wherein the recess (17) is provided in a first wall (10) and wherein the springs (13) are mounted on the inner side of a second wall (11).

12. Safety circuit system (1) according to one of claims 5-11, characterised in that the transponder (7) is mounted in a section of the coupling means (14) projecting beyond the base body (8a).

13. Safety circuit system (1) according to one of claims 1-12, characterised in that the coupling means (14) is formed by a plastic part.

14. Safety circuit system (1) according to one of claims 1-12, characterised in that the coupling means (14) is formed by a sheet metal part.

15. Safety circuit system (1) according to claim 14, characterised in that the part of the sheet metal part projecting beyond the base body (8a) forms a recess which is designed to receive (6) a plastic element (18), the transponder (7) being located in the region of the plastic element (18).