Safety switch arrangement

Abstract

A safety switch arrangement with a safety switch and an actuator associated with it. Moreover, a locking unit is provided for, by means of which the actuator is locked in a latched position. The safety switch has an auxiliary unlocking unit that has a mechanically actuatable actuating element. An actuation of the actuating element is implemented only with a transmission element as a positioning movement for the locking unit.

Claims

1. A safety switch arrangement (1) with a safety switch (2) and an actuator (3) associated with said safety switch arrangement, wherein the actuator is locked in a latched position by a locking unit, characterized in that the safety switch (2) has an auxiliary unlocking unit (14) that has a mechanically actuatable actuating element (15), wherein an actuation of the actuating element (15) is implemented only with a transmission element (16) as a positioning movement for the locking unit, and wherein a segment of the transmission element (16) forms a film hinge (19) that can be wound up or wound out on a shaft of the actuating element (15).

2. The safety switch arrangement (1) according to claim 1, characterized in that the locking unit is constructed to hold a blocking element (9) in a latched position, whereby the actuator (3) is locked in the latched position by means of the blocking element (9) held in the latched position.

3. The safety switch arrangement (1) according to claim 2, characterized in that the locking unit forms an electrically operating unit.

4. The safety switch arrangement (1) according to claim 2, characterized in that the locking unit is a component of the safety switch (2).

5. The safety switch arrangement (1) according to claim 2, characterized in that the position of the actuating element (15) is decoupled from the position of the blocking element (9) by the transmission element (16).

6. The safety switch arrangement (1) according to claim 1, characterized in that the transmission element (16) is a plastic injection molded part.

7. The safety switch arrangement (1) according to claim 1, characterized in that a segment of the transmission element (16) forms a push rod (18).

8. The safety switch arrangement (1) according to claim 1, characterized in that an end face of the shaft lies freely at the safety switch (2) and has an interface to insert a tool by means of which the shaft is rotatable about its longitudinal axis.

9. The safety switch arrangement (1) according to claim 1, characterized in that by winding up or winding out the film hinge (19) on the shaft, a linear motion of a push rod (18) is generated, which is transmitted to the locking unit.

10. The safety switch arrangement (1) according to claim 1, characterized in that a segment of the transmission element (16) is a spring element (20).

11. The safety switch arrangement (1) according to claim 1, characterized in that a segment of the transmission element (16) is a latching element.

12. The safety switch arrangement (1) according to claim 1, characterized in that the latched position of the actuator (3) is monitored by recording signals from a transponder in the actuator (3) into a reader unit of the safety switch (2).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention is explained below based on the drawings. The following is shown:

(2) FIG. 1A: First example of the inventive safety switch arrangement with a safety switch and an actuator wherein the actuator is locked in a latched position.

(3) FIG. 1B: Individual representation of the actuator of the safety switch arrangement in accordance with FIG. 1A.

(4) FIG. 2: Arrangement according to FIG. 1A in which the locking of the actuator is cancelled by means of an auxiliary unlocking unit.

(5) FIG. 3: Second example with a safety switch and an actuator, wherein the actuator is locked in a latched position.

(6) FIG. 4: Arrangement according to FIG. 3 in which the locking of the actuator is cancelled by means of an auxiliary unlocking unit.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(7) FIGS. 1A and 1B show schematically an exemplary embodiment of a safety switch arrangement 1 with a safety switch 2 and actuator 3.

(8) This safety switch arrangement 1 can be used, for example, to secure a safety door that serves as access to a hazard area. The actuator 3 can be arranged on the door, the safety switch 2 can be arranged on a frame bounding the door opening which is closed by the safety door.

(9) As is evident from FIGS. 1A and 1B, the actuator 3 has a core body 4 in which a connecting element 5 is mounted. The connection element 5 is formed by an elongated body, the cross section of which is at least approximately constant over its entire length.

(10) An actuator head 6 is borne on the connection element 5. In the present case, the actuator head 6 is designed to be spherically shaped, which is not compulsory, however. The actuator head 6 has a larger cross-sectional area than the connection element 5.

(11) The components of the safety switch 2 are integrated into a housing 7.

(12) On a side wall of the housing 7 of the safety switch 2, an opening 8 is provided into which a cavity in the safety switch 2 opens up, into which cavity the actuator head 6 can be inserted such that the actuator 3 is then in its latched position.

(13) To detect the latched position, a transponder (not shown) is provided within the actuator head 6. If the actuator head 6 is in the latched position, signals stored in the transponder can be read out by a reader unit integrated within the safety switch, whereby the latched position is detected.

(14) The opening 8 is circular in shape, wherein its diameter is somewhat larger than the diameter of the actuator head 6.

(15) The opening 8 is associated with a blocking element 9 that is borne on a rocker 10 that can be pivoted about a pivot axis S1.

(16) FIG. 1A shows the blocking element 9 in its latched position, in which it projects into the opening 8. When the actuator head 6 is inserted into the opening 8, the blocking element 9 is pushed downward and thereby the rocker 10 is pushed downward against the spring force of a spring 11.

(17) Once the actuator 3 has been inserted into the cavity, the rocker 10 is again pushed upward by the spring 11, such that the blocking element 9 is again moved into the latched position, in which the blocking element 9 projects into the opening 8.

(18) The safety switch 2 has a locking unit by means of which a locking of the blocking element 9 in its latched position can be effected, wherein the actuator 3 is latched in its latched position.

(19) In the present case, the locking unit consists of a hinged armature solenoid 12 and an anchor in the form of a pivoting lever 13 that is pivotable about a pivot axis S2.

(20) With the locking unit, a locking of the actuator 3 in the latched position is effected by the hinged armature solenoid 12 generating a magnetic field that holds the pivoting lever 13 in the blocked position shown in FIG. 1A, in which the free end of the rocker 10 engages in a recess 13a of the pivoting lever 13, such that the blocking element 9 is securely held in its latched position.

(21) A system, especially a system arranged inside a hazard area, is controlled using the safety switch arrangement 1. The safety switch 2 generates a release signal for releasing operation of the system only if the actuator 3 is detected in its latched position and if a locking of the actuator 3 in the latched position is effected by the locking unit.

(22) According to the invention, the safety switch 2 has an auxiliary unlocking unit 14. Using the auxiliary unlocking unit 14, the locking of the actuator can be cancelled, for example during a power failure, such that the actuator 3 can be released from its latched position.

(23) The auxiliary unlocking unit 14 has an actuating element 15 and a transmission element 16 that couples the actuating element 15 to the blocking element 9. The actuating element 15 essentially consists of a cylindrical shaft that is borne rotatably with one end face inside the housing 7. The second end face lies exposed at a wall of the housing 7. A slot 17 is worked into this face, into which slot a screwdriver can be inserted in order to rotate the shaft about its longitudinal axis.

(24) The transmission element 16 consists of a plastic injection molded part that has multiple segments that have various functionalities. A first segment forms a push rod 18 as a shear-resistant element for transmitting linear positioning movements, which in particular serve to release the blocking element 9 from the latched position. Furthermore the transmission element 16 has a film hinge 19 that can be wound up and wound out on the shaft. The film hinge 19 itself also has shear stiffness, such that it can be used to transmit protective motions onto the push rod 18.

(25) As protection against mechanical overload, the transmission element 16 has a spring element 20 as an additional segment.

(26) Finally, a segment (not shown) of the transmission element 16 forms a latching element that in an end position of the push rod 18 of the transmission element 16 is latched within a latching recess of the safety switch 2.

(27) By latching the latching element in the latching recess, the operator who actuates the actuating element 15 receives haptic feedback if the push rod 18 is in the end position shown in FIG. 2.

(28) The free end of the transmission element 16 forms a hook 21, which abuts the free end of the pivoting lever 13 of the locking unit. If the auxiliary unlocking unit 14 is not actuated, i.e., the film hinge 19 is wound out from the shaft, the hook 21 of the transmission element 16 abuts the pivoting lever 13 without appreciable contact force, such that the latter remains in its blocked position shown in FIG. 1A, in which the pivoting lever 13 effects the locking of the blocking element 9.

(29) The auxiliary unlocking of the blocking element 9 occurs in that an operator actuates the actuating element 15, i.e. using a screwdriver, rotates the shaft such that the film hinge 19 is wound up on the shaft, such that the transmission element 16 pulls the pivoting lever 13 out of its blocked position (FIG. 2). Accordingly, the rocker 10 is free and the actuator head 6 can be pulled out of the cavity of the safety switch 2, wherein once again here the blocking element 9 is pushed downward against the spring force.

(30) FIGS. 3 and 4 show another exemplary embodiment of the safety switch arrangement 1 according to the invention. The actuator 3 borne on a safety door or similar can be moved relative to the safety switch 2 by moving the safety door in the direction of motion indicated by the arrow I. FIGS. 3 and 4 show the actuator 3 in the latched position.

(31) A blocking element 9 in the form of a locking bolt is provided as a locking unit that can be displaced in the longitudinal direction of the safety switch 2 by means of a drive unit (not shown). FIG. 3 shows the locking bolt in activated locking. The locking bolt is in its latched position and protrudes beyond the face of the housing 7 of the safety switch 2 and projects into a recess 22 of the actuator 3, by means of which the latter is locked in its locked position. The locking bolts are held in the latched position by the spring force of a spring 11. The locking bolt is associated with an auxiliary unlocking unit 14, the construction of which correspondents to that of the auxiliary unlocking unit 14 in FIGS. 1 and 2, i.e. the auxiliary unlocking unit 14 has an actuating element 15 and a transmission element 16, wherein in this case the free end of the transmission element 16 is fastened to the locking bolt or can be brought to so engage.

(32) FIG. 3 shows the status when the auxiliary unlocking is not actuated.

(33) FIG. 4 shows the auxiliary unlocking that is effected by actuating the actuating element 15 and winding up the film hinge 19 onto the shaft. In so doing, the auxiliary unlocking unit 14 pulls the locking bolt back out of the locked position, against the spring force of the spring unit such that the locking bolt is inserted into the safety switch 2. The actuator 3 can then be moved out of its latched position.

(34) Naturally, the principle of auxiliary unlocking illustrated in the figures can also be applied to other designs of safety switches.

LIST OF REFERENCE NUMERALS

(35) (1) Safety switch arrangement (2) Safety switch (3) Actuator (4) Core body (5) Connection element (6) Actuator head (7) Housing (8) Opening (9) Blocking element (10) Rocker (11) Spring (12) Hinged armature solenoid (13) Pivoting lever (13a) Recess (14) Auxiliary unlocking unit (15) Actuating element (16) Transmission element (17) Slot (18) Push rod (19) Film hinge (20) Spring element (21) Hook (22) Recess S1, S2 Pivot axis I Direction of motion