Actuator units and safety switches

Abstract

To provide an actuator unit capable of not only absorbing a misalignment with respect to an actuator insertion hole in an arbitrary direction intersecting the insertion direction but also improving the durability.SOLUTION: An actuator unit 3 includes an actuator 3A having a tip 30 that can be inserted into an actuator insertion hole 20, and a base portion 3B that movably supports a base end portion 34 of the actuator 3A via a ball bearing 35 in the arrow B direction intersecting the arrow A direction, which is the insertion direction of the actuator 3A with respect to the actuator insertion hole 20, and the misalignment between the tip 30 of the actuator 3A and the actuator insertion hole 20 is absorbed by the movement of the base end portion 34 of the actuator 3A via the ball bearing 35.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to an actuator unit and a safety switch equipped with the same. [Background technology]

[0002] At the entrances and exits of dangerous areas where industrial machinery such as machine tools and industrial robots are installed, safety switches that turn on / off depending on whether the door is open or closed are installed.

[0003] Generally, a safety switch comprises an actuator that is arranged on the door side, and a switch body that is arranged on the wall side, has an actuator insertion hole, and has contacts that are switched in response to the movement of an internal operating rod; when the door is closed, the actuator on the door side is inserted into the actuator insertion hole of the switch body on the wall side, and the operating rod inside the switch body moves to switch the contacts.

[0004] In such a safety switch, the actuator may become misaligned with respect to the actuator insertion hole due to rattling of the door or misalignment of the door itself, and as a result, the actuator may not be able to be smoothly inserted into the actuator insertion hole when the door is closed. Therefore, various measures have been taken to prevent such a situation from occurring.

[0005] For example, in the actuator described in JP 2017-91877 A, the operation key (2) is supported on the base (3) so as to be able to swing, and the operation key (2) after swinging is returned to a reference position by the biasing force of the torsion coil spring (41). As a result, even if there is a large rattle of the door, the operation key (2) swings when inserted, and the operation key (2) is inserted into the key insertion port (103, 104) of the switch body (see paragraphs

[0037] ,

[0038] ,

[0044] , and Figs. 1, 13 to 15 of the same publication).

[0006] In the key switch described in JP 8-138500 A, the key body (9) of the operation key (3) is slidably mounted on the support shaft portion (12) of the holder portion (8), and the key body (9) is arranged to be in a neutral sliding position by the biasing force of the elastic body (13). Therefore, even if an assembly error or misalignment occurs in the operation key (3) and the switch body (2), the operation key (3) slides when inserted, so that the operation key (3) is inserted into the key hole (6) of the switch body (2) (see paragraphs

[0009] ,

[0020] and Figs. 1 to 3 of the same publication).

[0007] In the safety switch driver described in JP 11-317132 A, the base (3) of the key (2) is attached to the holder (1) via a circular PTFE slide bearing (or roller bearing) (9) so that it can slide, and the key (2) is biased to a central position by a spring (10). By displacing the base (3) of the key (2) along the mounting surface of the slide bearing (9), misalignment between the driver and the insertion slot of the safety switch is corrected (see claim 1, paragraphs

[0011] ,

[0012] , Figures 1, 3 and 4 of the same publication). Summary of the Invention [Problem to be solved by the invention]

[0008] In the switch described in JP 2017-91877 A, when there is a positional misalignment between the operation key (2) and the key insertion port (103, 104) of the switch body (100), the operation key (2) swings when inserted into the key insertion port (103, 104) to absorb the positional misalignment. This can accommodate positional misalignment in the swing direction of the operation key (2) (i.e., within the swing plane), but cannot accommodate positional misalignment in a direction intersecting (for example, perpendicular to) the swing direction.

[0009] In the device described in JP-A-8-138500, when there is a misalignment between the key body (9) of the operation key (3) and the key hole (6) of the switch body (2), the key body (9) slides when inserted into the key hole (6) to absorb the misalignment. Therefore, it is possible to accommodate misalignment in the sliding direction of the key body (9) (i.e., within the sliding plane), but it is not possible to accommodate misalignment in a direction intersecting the sliding direction (for example, perpendicular to the sliding direction).

[0010] In contrast, in the device described in JP 11-317132 A, when there is a misalignment between the key (2) and the insertion slot of the safety switch, the key (2) moves along the mounting surface of the slide bearing (9) when the key (2) is inserted into the insertion slot, thereby absorbing the misalignment, and therefore it is possible to accommodate misalignments in any direction.

[0011] However, when the door is closed with a misalignment between the key (2) and the insertion slot of the safety switch, an excessive impact load due to the inertia of the door acts on the base (3) of the key (2), which acts directly on the PTFE slide bearing, causing the PTFE slide bearing to be damaged and resulting in a durability problem. Note that JP-A-11-317132 describes that a roller bearing may be used instead of the PTFE slide bearing, but when a roller bearing is used, the base (3) of the key (2) can only be displaced in the rolling direction of the roller bearing, so while it is possible to accommodate misalignment in the rolling direction, it is not possible to accommodate misalignment in a direction intersecting (for example perpendicular to) the rolling direction.

[0012] The present invention has been made in consideration of the above-mentioned conventional situation, and the problem which the present invention aims to solve is to provide an actuator unit which not only can absorb positional misalignment with respect to the actuator insertion hole in any direction intersecting the insertion direction, but also can improve durability. [Means for solving the problem]

[0013] The actuator unit according to the present invention includes an actuator having a tip end that can be inserted into an actuator insertion hole, and a base end of the actuator that is oriented in a direction intersecting the direction in which the actuator is inserted into the actuator insertion hole. Any and a base portion that supports the actuator via a ball bearing in a direction such that the actuator can move freely in the direction of the actuator insertion hole. In any direction It is designed to be absorbed.

[0014] According to the present invention, the base end of the actuator intersects with the insertion direction of the actuator. Any In the actuator unit, the actuator is supported on the base part via a ball bearing so as to be freely movable in the insertion direction, and any misalignment between the tip end of the actuator and the actuator insertion hole is absorbed by the movement of the base end of the actuator via the ball bearing, so that any misalignment with respect to the actuator insertion hole can be absorbed in any direction intersecting the insertion direction. Moreover, according to the present invention, since the base end of the actuator is supported via a ball bearing, even if an excessive thrust load acts on the base end of the actuator due to an excessive load acting on the tip end of the actuator when a misalignment with the actuator insertion hole occurs, the base end of the actuator can be reliably supported by the ball bearing, thereby improving the durability of the actuator unit. In addition, since rolling friction is much smaller than sliding friction, the use of a ball bearing can reduce the coefficient of friction compared to the use of a slide bearing, which can realize smooth movement of the actuator and further improve durability.

[0015] In the present invention, the base end of the actuator has a holder that rotatably holds a plurality of balls, and each ball and the holder form a ball bearing.

[0016] In the present invention, the tip end of the actuator has a convex arcuate surface or an inclined surface, so that when the tip end abuts against the edge of the opening of the actuator insertion hole due to misalignment, the base end of the actuator can move smoothly.

[0017] In the present invention, a first elastic support member that elastically supports the actuator from its outer periphery is provided on the base portion. In this case, the actuator can be returned to its original position after it has moved by the biasing force of the first elastic support member.

[0018] In the present invention, the actuator has a shaft portion extending between a distal end and a proximal end, and the base portion has an aperture through which the shaft portion passes to allow movement of the proximal end.

[0019] In the present invention, a step is formed between the shaft portion and the tip portion.

[0020] In the present invention, a first elastic support member that elastically supports the shaft of the actuator from its outer periphery is provided on the base part. In this case, the actuator can be returned to its original position after it has moved by the biasing force of the first elastic support member.

[0021] In the present invention, the first elastic support member covers the opening in the base portion.

[0022] In the present invention, the actuator has a locking hole that is locked to a locking member inside the switch body having an actuator insertion hole.

[0023] In the present invention, a second elastic support member is provided on the base portion to elastically support the base end of the actuator in the actuator insertion direction. In this case, the thrust load acting on the actuator during insertion of the actuator in the event of misalignment can be borne by the second elastic support member, improving the durability of the ball bearing.

[0024] In the present invention, an arc-shaped plate member having a concave arc-shaped surface forming the rolling surface of the ball bearing is provided on the base portion, and the arc-shaped plate member is elastically supported by the second elastic support member. In this case, since the rolling surface of the ball bearing is formed by the concave arc-shaped surface of the arc-shaped plate member, the base end of the actuator can be easily returned to its original position.

[0025] A safety switch according to the present invention comprises the actuator unit according to claim 1 and a switch body having an actuator insertion hole. Effect of the Invention

[0026] As described above, according to the present invention, misalignment between the tip end of the actuator and the actuator insertion hole can be absorbed in any direction intersecting the insertion direction of the actuator. Moreover, according to the present invention, even if an excessive load acts on the tip end of the actuator when misalignment occurs, causing an excessive thrust load to act on the actuator, the base end of the actuator can be reliably supported by the ball bearing, thereby improving the durability of the actuator unit. [Brief description of the drawings]

[0027] [Figure 1] 1 is a diagram showing a schematic configuration of a safety switch including an actuator unit and a switch main body according to an embodiment of the present invention; [Diagram 2] FIG. 2 is an overall perspective view of the actuator unit (FIG. 1). [Diagram 3] FIG. 3 is a plan view of the actuator unit (FIG. 2). [Figure 4] 4 is a bottom view taken along line IV-IV in FIG. 1 with a bottom cover removed from the actuator unit (FIG. 2). [Diagram 5] 5 is a cross-sectional view taken along line VV in FIG. 4, showing a vertical cross section of the actuator unit (FIG. 2). [Figure 6]6 is a cross-sectional view taken along line VI-VI in FIG. 5, showing a cross section of a base portion of the actuator unit (FIG. 2). [Figure 7] FIG. 2 is a diagram showing a state in which the actuator is inserted inside the switch body in the safety switch (FIG. 1). [Figure 8] 5A to 5C are views showing, in the safety switch (FIG. 1), movements of the actuator unit and the actuator in a time series manner in the case where the actuator unit is misaligned with respect to an actuator insertion hole of the switch body. [Figure 9] 5A to 5C are views showing, in the safety switch (FIG. 1), movements of the actuator unit and the actuator in a time series manner in the case where the actuator unit is misaligned with respect to an actuator insertion hole of the switch body. [Figure 10] 5A to 5C are views showing, in the safety switch (FIG. 1), movements of the actuator unit and the actuator in a time series manner in the case where the actuator unit is misaligned with respect to an actuator insertion hole of the switch body. [Figure 11] FIG. 12 is a plan view of the actuator unit (FIG. 10) and corresponds to FIG. [Figure 12] 12 is a bottom view taken along line XII-XII in FIG. 10 with a bottom cover removed from the actuator unit (FIG. 10). FIG. [Figure 13] 13 is a vertical cross-sectional view taken along line XIII-XIII in FIG. 12, showing a vertical cross-section of the actuator unit (FIG. 10). [Figure 14] 14 is a cross-sectional view taken along line XIV-XIV in FIG. 13, showing a cross section of the base portion of the actuator unit (FIG. 10). [Figure 15] FIG. 9 is a diagram showing a state in which the actuator (FIG. 8) is inserted into the switch body. [Figure 16] FIG. 16 is a cross-sectional view of an actuator unit according to a first modified example of the present invention (FIG. 18) taken along line XVI-XVI, which corresponds to FIG. 6 of the above embodiment. [Figure 17] FIG. 19 is a bottom view of the actuator unit (FIG. 18) and corresponds to FIG. 4 of the embodiment. [Figure 18] 18 is a cross-sectional view taken along line XVIII-XVIII in FIG. 17. [Figure 19] FIG. 18 shows a state after the actuator has moved when there is a positional deviation between the actuator unit (FIG. 18) and the actuator insertion hole of the switch body, and corresponds to FIG. 14 of the embodiment. [Figure 20] FIG. 27 is a cross-sectional view of an actuator unit according to a second modified example of the present invention (FIG. 22), taken along line XX-XX, and corresponding to FIG. 6 of the above embodiment. [Figure 21] FIG. 23 is a bottom view of the actuator unit (FIG. 22) and corresponds to FIG. 4 of the embodiment. [Figure 22] 22 is a cross-sectional view taken along line XXII-XXII of FIG. 21. [Figure 23] FIG. 22 shows a state after the actuator has moved when there is a positional deviation between the actuator unit (FIG. 22) and the actuator insertion hole of the switch body, and corresponds to FIG. 14 of the embodiment. [Figure 24] FIG. 27 is a cross-sectional view of an actuator unit according to a third modified example of the present invention (FIG. 26), taken along line XXIV-XXIV, and corresponds to FIG. 6 of the above embodiment. [Diagram 25] FIG. 27 is a bottom view of the actuator unit (FIG. 26) and corresponds to FIG. 4 of the embodiment. [Figure 26] 26 is a cross-sectional view taken along line XXVI-XXVI of FIG. 25. [Figure 27] 26 shows a state after the actuator has moved when there is a positional deviation between the actuator unit (FIG. 26) and the actuator insertion hole of the switch body, and corresponds to FIG. 14 of the embodiment. [Figure 28] FIG. 31 is a cross-sectional view of an actuator unit according to a fourth modified example of the present invention (FIG. 30), taken along line XXVIII-XXVIII, and corresponds to FIG. 6 of the above-described embodiment. [Figure 29] FIG. 31 is a bottom view of the actuator unit (FIG. 30), which corresponds to FIG. 4 of the embodiment. [Diagram 30] This is a cross-sectional view taken along line XXX-XXX in Figure 29. [Diagram 31] FIG. 30 shows a state after the actuator has moved when there is a positional deviation between the actuator unit (FIG. 30) and the actuator insertion hole of the switch body, and corresponds to FIG. 14 of the embodiment. [Diagram 32] FIG. 32 is a cross-sectional view of an actuator unit according to a fifth modified example of the present invention (FIG. 34) taken along line XXXII-XXXII, which corresponds to FIG. 6 of the above embodiment. [Diagram 33] FIG. 35 is a bottom view of the actuator unit (FIG. 34) and corresponds to FIG. 4 of the embodiment. [Diagram 34] This is a cross-sectional view taken along line XXXIV-XXXIV in Figure 33. [Diagram 35] 35 shows a state after the actuator has moved when the actuator unit (FIG. 34) is misaligned with respect to the actuator insertion hole of the switch body, and corresponds to FIG. 14 of the embodiment. [Diagram 36] FIG. 13 is an overall perspective view of an actuator unit according to a sixth modified example of the present invention, which corresponds to FIG. 2 of the above embodiment. [Figure 37] FIG. 37 is a vertical cross-sectional view of the actuator unit (FIG. 36) with the bottom cover removed, and corresponds to FIG. 5 of the embodiment. [Figure 38] FIG. 37 is a bottom view of the actuator unit (FIG. 36) with the bottom cover removed, and corresponds to FIG. 4 of the embodiment. [Figure 39] FIG. 37 shows a state after the actuator has moved when the actuator unit (FIG. 36) is misaligned with respect to the actuator insertion hole of the switch body, and corresponds to FIG. 13 of the embodiment. [Diagram 40]FIG. 13 is a schematic vertical sectional view of an actuator unit according to a seventh modified example of the present invention. [Diagram 41] FIG. 40 shows a state after the actuator has moved when the actuator unit (FIG. 40) is misaligned with respect to the actuator insertion hole of the switch body, and corresponds to FIG. 13 of the embodiment. [Diagram 42] FIG. 13 is a schematic vertical sectional view of an actuator unit according to an eighth modified example of the present invention. [Diagram 43] FIG. 42 shows a state after the actuator has moved when there is a positional deviation between the actuator unit (FIG. 42) and the actuator insertion hole of the switch body, and corresponds to FIG. 13 of the embodiment. [Diagram 44] FIG. 13 is a schematic vertical sectional view of an actuator unit according to a ninth modified example of the present invention. [Diagram 45] FIG. 44 shows a state after the actuator has moved when the actuator unit (FIG. 44) is misaligned with respect to the actuator insertion hole of the switch body, and corresponds to FIG. 13 of the embodiment. [Diagram 46] FIG. 23 is a diagram showing a schematic configuration of a safety switch including an actuator unit and a switch main body according to a tenth modified example of the present invention. [Figure 47] FIG. 47 is a vertical cross-sectional view of the actuator unit (FIG. 46) with the bottom cover removed, and corresponds to FIG. 5 of the embodiment. [Figure 48] 47A to 47C are views showing, in the safety switch (FIG. 46), movements of the actuator unit and the actuator in a time series manner in the case where the actuator unit is misaligned with respect to the actuator insertion hole of the switch body. [Figure 49] 47A to 47C are views showing, in the safety switch (FIG. 46), movements of the actuator unit and the actuator in a time series manner in the case where the actuator unit is misaligned with respect to the actuator insertion hole of the switch body. [Figure 50]47A to 47C are views showing, in the safety switch (FIG. 46), movements of the actuator unit and the actuator in a time series manner in the case where the actuator unit is misaligned with respect to the actuator insertion hole of the switch body. [Figure 51] FIG. 47 shows a state after the actuator has moved when the actuator unit (FIG. 47) is misaligned with respect to the actuator insertion hole of the switch body, and corresponds to FIG. 13 of the embodiment. [Figure 52] FIG. 51 is a schematic view taken along line LII in FIG. 50, and corresponds to FIG. 7 in the embodiment. [Figure 53] FIG. 17 is a bottom view of an actuator unit according to an eleventh modified example of the present invention with the bottom cover removed, showing a modified example of the base end portion in FIG. 4 of the above embodiment. [Figure 54] FIG. 12 shows an actuator unit according to a twelfth modified example of the present invention, and corresponds to FIG. 6 of the above embodiment. [Figure 55] FIG. 23 shows an actuator unit according to a thirteenth modified example of the present invention, and corresponds to FIG. 16 showing the first modified example. [Figure 56] FIG. 32 showing the actuator unit according to a fourteenth modified example of the present invention. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0028] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. 1 to 15 are diagrams for explaining an actuator unit according to one embodiment of the present invention and a safety switch equipped with the same, in which FIG. 1 is a schematic configuration diagram of the safety switch, FIG. 2 is an overall perspective view of the actuator unit, FIG. 3 is a plan view thereof, FIG. 4 is a bottom view (view taken along line IV-IV in FIG. 1) with the bottom cover removed from the actuator unit, FIG. 5 is a vertical sectional view (sectional view taken along line VV in FIG. 4) with the bottom cover removed from the actuator unit, FIG. 6 is a sectional view taken along line VI-VI in FIG. 5, and FIG. 7 is a diagram showing a state in which the actuator has been inserted into the switch body from the state shown in FIG. 1. 8 to 10 are diagrams showing the state in which the actuator unit and the actuator are inserted into the switch body when the actuator unit is misaligned with respect to the actuator insertion hole of the switch body; FIG. 11 is a plan view after the actuator has been moved; FIG. 12 is a bottom view after the actuator has been moved (view taken along line XII-XII in FIG. 10); FIG. 13 is a vertical cross-sectional view after the actuator has been moved (cross-sectional view taken along line XIII-XIII in FIG. 12); FIG. 14 is a cross-sectional view taken along line XIV-XIV in FIG. 13; and FIG. 15 is a diagram showing the state in which the actuator has been inserted into the switch body from the state shown in FIG. 8.

[0029] As shown in Fig. 1, the safety switch 1 according to this embodiment includes a switch body 2 that is disposed, for example, on a wall or a fixed door (not shown), and an actuator unit 3 that is disposed, for example, on a sliding movable door (not shown) and is provided so as to be insertable and removable from the switch body 2. Fig. 1 shows the movable door as viewed from the front, and in the figure, an arrow A indicates the insertion direction of the actuator unit 3. Note that Fig. 1 shows a state in which the movable door is in the middle of closing, and is shown in a state in which the movable door is slightly open.

[0030] The switch body 2 has one or more actuator insertion holes 20. The actuator insertion holes 20 are, for example, circular tapered holes that penetrate the wall of the switch body 2, and have a tapered surface 20a that gradually decreases in diameter from the outer surface of the wall of the switch body 2 toward the inside of the switch body 2. Lindicates the center line of the actuator insertion hole 20. Although not shown, a switchable contact is provided inside the switch body 2, and a locking member (described later) that locks onto the inserted actuator unit 3 is also provided.

[0031] The actuator unit 3 has an actuator 3A having a tip portion 30 that can be inserted into the actuator insertion hole 20 of the switch body 2, and a base portion 3B that houses the base end side of the actuator 3A. The tip portion 30 is, for example, a semispherical protrusion, and has a convex arcuate surface 30a arranged on the tip side and a flat surface 30b arranged on the rear end side, and the tip of a shaft portion 31, for example, a columnar shape extending in the axial direction, is integrally connected to the flat surface 30b. The shaft portion 31 is a member having a smaller diameter than the tip portion 30, and the flat surface 30b forms a step with respect to the tip of the shaft portion 31. In FIG. 1, the dashed line 3C L indicates the center line in the axial direction of the shaft portion 31 (i.e., the actuator 3A), and in this example, the center line 3C L is the center line 2C of the actuator insertion hole 20 of the switch body 2 L The corresponding state is shown.

[0032] 2 and 3, the base portion 3B is, for example, a box-shaped member, and includes a box-shaped base body 32 having, at one end, for example, a circular opening 32a through which the shaft portion 31 of the actuator 3A is inserted and an open other end, and a thin plate-like lid 33 that covers the opening at the other end of the base body 32. The inner diameter of the opening 32a is larger than the outer diameter of the shaft portion 31 by, for example, several millimeters to 10-odd millimeters so as to allow the shaft portion 31 to move within the opening 32a. The base body 32 is also formed with a plurality of screw insertion holes 32b into which mounting screws (not shown) for the lid body 33 and mounting screws (not shown) for mounting the actuator unit 3 to a movable door are inserted.

[0033] As shown in FIG. 4 and FIG. 5, the base end 34 of the actuator 3A is accommodated inside the base portion 3B. The base end 34 is a disk-shaped member arranged at the rear end of the shaft portion 31 and has a larger diameter than the shaft portion 31, and is integrally connected to the rear end of the shaft portion 31. That is, the shaft portion 31 extends between the tip portion 30 and the base end 34 of the actuator 3A. A plurality of (five in this example) circular holding holes 34a are formed in the rear end surface of the base end 34. The holding holes 34a are arranged at equal or approximately equal intervals on the circumference. A steel ball (i.e., a steel ball) 35, for example, is accommodated in each holding hole 34a, and each ball 35 is supported in each holding hole 34a so as to be rotatable (i.e., freely rotating). Each holding hole 34a is filled with, for example, grease as a lubricant. The bottom of each retaining hole 34a is formed, for example, in a tapered shape, and the depth of each retaining hole 34a is set so that a part of each housed ball 35 peeks out (i.e., protrudes) from the open end of each retaining hole 34a (i.e., the rear end surface of the base end portion 34) (see FIG. 5). Each retaining hole 34a and each ball 35 constitutes a ball bearing. In this case, the base end portion 34 itself constitutes the holder (i.e., the retainer) for the ball bearing.

[0034] 4 and 5 show a state where the lid 33 (FIG. 1) is removed from the base 3B. In a state where the lid 33 is attached, as shown by the dashed line in FIG. 5, each ball 35 protruding from the rear end surface of the base end 34 abuts against the inner surface of the lid 33 and is movable along the inner surface in the direction of arrow B. Here, the direction of arrow B refers to any direction perpendicular or substantially perpendicular (i.e., intersecting) to the direction of arrow A, which is the insertion direction of the actuator unit 3. That is, the direction of arrow B includes not only the direction within the plane of FIG. 5, but also all directions that form an angle to the front side and the back side with respect to the plane of the figure. To explain this with reference to FIG. 4, the base end 34 is movable in any direction within the plane of the figure, including the vertical direction, horizontal direction, and diagonal direction. As described above, the opening 32a formed on one end side of the base portion 3B is formed larger than the shaft portion 31 so as to allow movement of the shaft portion 31 within the opening 32a (Figures 2 and 3), thereby enabling movement of the base end portion 34 (and therefore movement of the actuator 3A) relative to the base portion 3B.

[0035] As shown in Fig. 5, the shaft portion 31 of the actuator 3A has a flange portion 31f that protrudes outwardly within the base portion 3B. The flange portion 31f is, for example, a disk-shaped member. The flange portion 31f is disposed at a predetermined interval from the base end portion 34. A plurality of (four in this example) wires (first elastic support members) 371, 372, 373, 374 extending in a direction perpendicular or substantially perpendicular (i.e. intersecting) to the direction of the arrow A are disposed between the flange portion 31f and the base end portion 34 (see Fig. 4). Each of the wires 371, 372, 373, 374 is formed of, for example, a high-tensile steel wire such as a piano wire, other steel wire, metal wire, or the like.

[0036] As shown in FIG. 6, the wires 371, 372 are arranged in parallel in the vertical direction of the figure so as to sandwich the shaft portion 31 from both the left and right sides of the figure, and the wires 373, 374 are arranged in parallel in the horizontal direction of the figure so as to sandwich the shaft portion 31 from both the top and bottom sides of the figure. That is, the wires 371, 372, 373, 374 are arranged in a lattice shape. The wires 371, 372 are arranged on the front side of the paper surface of FIG. 6 with respect to the wires 373, 374. The base body 32 of the base portion 3B is provided with a plurality of (eight in this example) support columns 36 each extending in a direction perpendicular to the paper surface of FIG. 6. Each of the wires 371 to 374 is sandwiched between two support columns 36 and the shaft portion 31, and elastically abuts against the outer circumferential surface of the shaft portion 31. As a result, the shaft portion 31 (and therefore the actuator 3A) is elastically supported from the outer circumferential side by the wires 371 to 374.

[0037] 5, a washer 38 is disposed between the flange portion 31f of the shaft portion 31 of the actuator 3A and the front wall portion of the base body 32 of the base portion 3B. The washer 38 is a thin-walled circular (donut-shaped) member, and has an opening 38a through which the shaft portion 31 of the actuator 3A is inserted. The inner diameter of the opening 38a is larger than the outer diameter of the shaft portion 31 and smaller than the opening 32a of the base body 32. The outer diameter of the washer 38 is also larger than the opening 32a.

[0038] Next, the effects of this embodiment will be described. When the movable door is moved in the closing direction from the state shown in Fig. 1, the actuator 3A of the actuator unit 3 moves in the direction of the arrow A, and as shown in Fig. 7, the actuator 3A passes through the actuator insertion hole 20 of the switch body 2 and is inserted into the inside of the switch body 2. During this insertion, as described above, the center line 3C of the actuator 3A L is the center line 2C of the actuator insertion hole 20 of the switch body 2 LTherefore, the tip 30 of the actuator 3A is smoothly inserted into the switch body 2 without interfering with the tapered surface 20a of the actuator insertion hole 20. Then, the locking member SR inside the switch body 2 locks the flat surface 30b that forms the step between the tip 30 and the shaft 31 of the actuator 3A. This locks the actuator 3A and prevents it from coming off. From this state, the contacts (not shown) inside the switch body 2 switch, and the operation of a machine such as a robot begins.

[0039] On the other hand, as shown in FIG. 8, the center line 3C of the shaft portion 31 (i.e., the actuator 3A) L is the center line 2C of the actuator insertion hole 20 of the switch body 2 L Let us assume that there is a positional deviation with respect to the center line 3C, and the distance of the positional deviation (i.e., the offset amount) is e. L is the center line 2C L 4, the position is shifted upward by a distance e with respect to the target position.

[0040] When the movable door is moved in the closing direction from this state, the actuator 3A of the actuator unit 3 moves in the direction of arrow A, and as shown in Fig. 9, the tip 30 of the actuator 3A abuts against the tapered surface 20a of the actuator insertion hole 20 of the switch body 2. At this time, the convex arc-shaped surface 30a of the tip 30 abuts against the tapered surface 20a, so that while the movable door is closed, the convex arc-shaped surface 30a of the tip 30 tries to move obliquely downward in the figure while sliding on the tapered surface 20a along the tapered surface 20a.

[0041] At this time, as explained using Fig. 5, each ball 35 protruding from the rear end surface of the base end 34 of the actuator 3A is movable in the direction of arrow B along the inner surface of the cover body 33, so that when a force is applied to move the tip end 30 of the actuator 3A downward while the movable door is closed, each ball 35 rolls on the inner surface of the cover body 33, so that the base end 34 moves downward along the inner surface of the cover body 33 (see Fig. 13). Note that at this time, as described above, the opening 32a formed on one end side of the base part 3B is formed larger than the shaft part 31 so as to allow the shaft part 31 to move within the opening 32a (see Figs. 2 and 3), so that the movement of the base end 34 (and therefore the movement of the actuator 3A) relative to the base part 3B is smooth.

[0042] As a result, the tip 30 of the actuator 3A moves obliquely downward in FIG. 9 along the tapered surface 20a of the actuator insertion hole 20, and as shown in FIG. 10, the tip 30 is inserted into the actuator insertion hole 20. When the movable door further moves in the closing direction from this state, the tip 30 of the actuator 3A passes through the actuator insertion hole 20 of the switch body 2 and is inserted into the inside of the switch body 2. Then, as shown in FIG. 15, the locking member SR inside the switch body 2 locks the flat surface 30b that forms the step between the tip 30 and the shaft 31 of the actuator 3A. This locks the actuator 3A and prevents it from coming off. From this state, the contacts (not shown) inside the switch body 2 are switched, and the operation of a machine such as a robot is started.

[0043] Thus, according to this embodiment, if the tip end 30 of the actuator 3A is misaligned with respect to the actuator insertion hole 20 of the switch body 2, the misalignment is absorbed by movement of the base end 34 of the actuator 3A via the ball bearing, thereby making it possible to absorb the misalignment of the actuator 3A with respect to the actuator insertion hole 20 in any direction (arrow B direction) intersecting the actuator insertion direction (arrow A direction).

[0044] Moreover, according to this embodiment, because the base end 34 of the actuator 3A is supported via a ball bearing, even if an excessive thrust load acts on the base end 34 of the actuator 3A as a result of an excessive load acting on the tip end 30 of the actuator 3A when the actuator is misaligned with the actuator insertion hole 20, the base end 34 of the actuator 3A can be reliably supported by the ball bearing, thereby improving the durability of the actuator unit 3. Also, because rolling friction is much smaller than sliding friction, the use of a ball bearing can reduce the friction coefficient compared to the use of a slide bearing, thereby achieving smoother movement of the actuator 3A and further improving durability.

[0045] When the base end 34 of the actuator 3A moves downward, as shown in FIG. 13, the washer 38 also moves downward slightly in association with the downward movement of the shaft portion 31. However, even in this case, the upper region of the flange portion 31f within the opening 32a of the base body 32 is blocked by the washer 38, so that the inside of the base portion 3B is not exposed to the outside through the opening 32a.

[0046] When the tip portion 30 of the actuator 3A is inserted into the switch body 2, the tip portion 30 and the base portion 34 each move downward (see Figs. 11 and 12), and at this time, as shown in Fig. 14, the shaft portion 31 of the actuator 3A also moves downward, abutting against the lower wire 374 and elastically deforming it downward. Therefore, at this time, an elastic repulsive force due to the elastic deformation of the wire 374 acts upward on the outer circumferential surface of the shaft portion 31.

[0047] Therefore, when the movable door is opened and the tip portion 30 of the actuator 3A tries to leave the actuator insertion hole 20 of the switch body 2 as the movable door moves, the shaft portion 31 (and therefore the actuator 3A) tries to move upward due to the elastic repulsive force of the wire 374 acting on the shaft portion 31. At this time, the base end portion 34 of the actuator 3A is movable by the ball bearing, so the upward movement of the actuator 3A is performed smoothly.

[0048] In the above embodiment, an example was given of a case in which actuator 3A is misaligned upward with respect to actuator insertion hole 20, and when the misalignment is absorbed, shaft 31 of actuator 3A comes into contact with lower wire 374, elastically deforming wire 374 downward. In the case of a downward misalignment, shaft 31 comes into contact with upper wire 373, elastically deforming it upward, and in the case of a left / right misalignment, shaft 31 comes into contact with left / right wire 371 or 372, elastically deforming wire 371 or 372 to the left or right in FIG. 6.

[0049] [First Modification] 16 to 19 show a first modified example of the present invention (particularly a modified example of the first elastic support member), and in each figure, the same reference numerals as those in the above embodiment indicate the same or corresponding parts. In the above embodiment, four wires each extending linearly are used, and the wires 371, 372, 373, 374 are arranged in a lattice pattern in the vertical and horizontal directions (see Figs. 4 and 6), but in this first modified example, four torsion coil springs 37C1, 37C2, 37C3, 37C4 are used as the first elastic support member.

[0050] 16, the coil portion of torsion coil spring 37C1 is attached to support column 361 of base body 32, its fixed arm portion 371' is engaged with the inner wall surface of base body 32, and movable arm portion 371 is in elastic contact with the outer circumferential surface of shaft portion 31 (see FIG. 16). Similarly, the coil portion of torsion coil spring 37C2 is attached to support column 362, its fixed arm portion 372' is engaged with the inner wall surface of base body 32, and movable arm portion 372 is in elastic contact with the outer circumferential surface of shaft portion 31. The coil portion of torsion coil spring 37C3 is attached to support column 363, its fixed arm portion 373' is engaged with the inner wall surface of base body 32, and movable arm portion 373 is in elastic contact with the outer circumferential surface of shaft portion 31. The coil portion of the torsion coil spring 37C4 is attached to the support 364, the fixed arm portion 374' is engaged with the inner wall surface of the base body 32, and the movable arm portion 374 is in elastic contact with the outer circumferential surface of the shaft portion 31.

[0051] As a result, the movable arms 371, 372, 373, 374 of each torsion coil spring 37C1, 37C2, 37C3, 37C4 are arranged in a lattice pattern in diagonal directions and diagonal directions perpendicular or nearly perpendicular to the diagonal directions, and the shaft portion 31 (and therefore the actuator 3A) is elastically supported from the outer periphery by the movable arms 371, 372, 373, 374 of each torsion coil spring 37C1, 37C2, 37C3, 37C4.

[0052] As shown in FIG. 18, the movable arms 371, 372, 373, and 374 of the torsion coil springs 37C1, 37C2, 37C3, and 37C4 are disposed between the base end 34 of the actuator 3A and the flange portion 31f, similar to the wires 371, 372, 373, and 374 of the previous embodiment.

[0053] Even in this first modified example, if the tip end 30 of the actuator 3A is misaligned with respect to the actuator insertion hole 20 of the switch body 2 (see Figure 8 of the above embodiment), the misalignment is absorbed by movement of the base end 34 of the actuator 3A via the ball bearing (see Figures 17 and 18). Not only can the misalignment of the actuator 3A with respect to the actuator insertion hole 20 be absorbed in any direction (arrow B direction) intersecting the actuator insertion direction (arrow A direction), but since the base end 34 is supported via a ball bearing, the base end 34 can be reliably supported by the ball bearing when an excessive thrust load acts on the base end 34 when the actuator 3A is inserted.

[0054] Furthermore, when the tip 30 of the actuator 3A is inserted into the switch body 2 in a state where it is displaced upward (see FIG. 15 of the above embodiment), the tip 30 and the base end 34 move downward, causing the shaft 31 to move downward as well, and at this time, the shaft 31 comes into contact with the lower movable arms 372, 373, elastically deforming them downward (see FIG. 19). Therefore, at this time, an elastic repulsive force due to the elastic deformation of the movable arms 372, 373 acts upward on the outer circumferential surface of the shaft 31.

[0055] Therefore, when the movable door is opened and the tip portion 30 of the actuator 3A tries to leave the actuator insertion hole 20 of the switch body 2 as the movable door moves, the shaft portion 31 (and therefore the actuator 3A) tries to move upward due to the elastic repulsive force of each of the movable arms 372, 373 acting on the shaft portion 31. At this time, the base end portion 34 of the actuator 3A is movable by the ball bearing, so the upward movement of the actuator 3A is performed smoothly.

[0056] In Figure 19, an example has been described in which actuator 3A is displaced upward relative to actuator insertion hole 20, and when the displacement is absorbed, shaft 31 of actuator 3A abuts against each of the lower movable arms 372, 373, elastically deforming each of the movable arms 372, 373 downward. In the case of a downward displacement, shaft 31 abuts against each of the upper movable arms 371, 374, elastically deforming each of the movable arms 371, 374 upward, and in the case of a left-right displacement, shaft 31 abuts against each of the left and right movable arms 373, 374 or 371, 372, elastically deforming each of the movable arms 373, 374 or 371, 372 to the left or right in Figure 16.

[0057] [Second Modification] 20 to 23 show a second modified example of the present invention (particularly a modified example of the first elastic support member), and in each figure, the same reference numerals as those in the above embodiment or the first modified example indicate the same or corresponding parts. In the above embodiment, four wires each extending linearly are used, and the wires 371, 372, 373, 374 are arranged in a lattice pattern in the vertical and horizontal directions (see Figs. 4 and 6), but in this second modified example, four tension coil springs 37C1, 37C2, 37C3, 37C4 are used as the first elastic support member.

[0058] As shown in Fig. 20, the tension coil springs 37C1 and 37C3 are arranged in the up-down direction, and the tension coil springs 37C2 and 37C4 are arranged in the left-right direction, and the tension coil springs 37C1, 37C2, 37C3, and 37C4 are arranged in a cross shape on an extension line passing through the center O of the shaft portion 31 of the actuator 3A. The hook portion at one end of the tension coil spring 37C1 is engaged with the support 361 of the base main body 32, and the hook portion at the other end is engaged with the locking protrusion 31fa protruding rearward (to the right in the figure) from the rear end surface of the flange portion 31f of the actuator 3A as shown in Fig. 22 (see Fig. 20). Similarly, the hook portion at one end of the tension coil spring 37C2 is engaged with the support 362 of the base main body 32, and the hook portion at the other end is engaged with the locking protrusion 31fa of the flange portion 31f. A hook portion at one end of the tension coil spring 37C3 is engaged with the support 363 of the base body 32, and the hook portion at the other end is engaged with the locking projection 31fa of the flange portion 31f. A hook portion at one end of the tension coil spring 37C4 is engaged with the support 364 of the base body 32, and the hook portion at the other end is engaged with the locking projection 31fa of the flange portion 31f.

[0059] As a result, the shaft portion 31 (and therefore the actuator 3A) is elastically supported from the outer periphery by the tension coil springs 37C1, 37C2, 37C3, and 37C4. The tension coil springs 37C1, 37C2, 37C3, and 37C4 are disposed between the base end portion 34 of the actuator 3A and the flange portion 31f, similar to the wires 371, 372, 373, and 374 of the above embodiment, as shown in FIG.

[0060] Even in this second modified example, if the tip end 30 of the actuator 3A is misaligned with respect to the actuator insertion hole 20 of the switch body 2 (see Figure 8 of the above embodiment), the misalignment is absorbed by movement of the base end 34 of the actuator 3A via the ball bearing (see Figures 21 and 22). Not only can the misalignment of the actuator 3A with respect to the actuator insertion hole 20 be absorbed in any direction (arrow B direction) intersecting the actuator insertion direction (arrow A direction), but since the base end 34 is supported via a ball bearing, the base end 34 can be reliably supported by the ball bearing when an excessive thrust load acts on the base end 34 when the actuator 3A is inserted.

[0061] Furthermore, when the tip 30 of the actuator 3A is inserted into the switch body 2 in a state where it is displaced upward (see FIG. 15 of the above embodiment), the tip 30 and the base end 34 move downward, causing the shaft 31 to move downward as well, at which point the lower tension coil spring 37C3 is compressed and the upper and left and right tension coil springs 37C1, 37C2, 37C4 are tensilely deformed, as shown in FIG. 23. At this time, an elastic repulsive force caused by the elastic deformation of the tension coil springs 37C1, 37C2, 37C3, 37C4 acts upward on the outer periphery of the shaft 31.

[0062] Therefore, when the movable door is opened and the tip portion 30 of the actuator 3A tries to leave the actuator insertion hole 20 of the switch body 2 as the movable door moves, the shaft portion 31 (and therefore the actuator 3A) tries to move upward due to the elastic repulsive forces of the tension coil springs 37C1, 37C2, 37C3, and 37C4 acting on the shaft portion 31. At this time, the base end portion 34 of the actuator 3A is movable by the ball bearings, so the upward movement of the actuator 3A is performed smoothly.

[0063] 23 has been described as an example in which, due to an upward positional displacement of the actuator 3A with respect to the actuator insertion hole 20, when the positional displacement is absorbed, the lower tension coil spring 37C3 is compressively deformed and the upper and left and right tension coil springs 37C1, 37C2, and 37C4 are tensilely deformed. In the case of a downward positional displacement, the upper tension coil spring 37C1 is compressively deformed and the lower and left and right tension coil springs 37C2, 37C3, and 37C4 are tensilely deformed; in the case of a leftward positional displacement, the right tension coil spring 37C2 is compressively deformed and the upper, lower and left tension coil springs 37C1, 37C3, and 37C4 are tensilely deformed; and in the case of a rightward positional displacement, the left tension coil spring 37C4 is compressively deformed and the upper, lower and right tension coil springs 37C1, 37C2, and 37C3 are tensilely deformed.

[0064] [Third Modification] 24 to 27 show a third modified example of the present invention (particularly a modified example of the first elastic support member), and in each figure, the same reference numerals as those in the above embodiment and the first or second modified example indicate the same or corresponding parts. In the above embodiment, four wires each extending linearly are used, and wires 371, 372, 373, 374 are arranged in a lattice pattern in the vertical and horizontal directions (see Figs. 4 and 6), but in this third modified example, a single spiral spring 37C is used as the first elastic support member.

[0065] As shown in FIG. 24, one end 37Ca on the inner periphery of the spiral spring 37C is engaged with a locking recess formed in the outer periphery of the shaft portion 31 of the actuator 3A, and the other end 37Cb on the outer periphery is engaged with a locking recess formed in the inner wall surface of the base body 32 of the base portion 3B.

[0066] As a result, the shaft portion 31 (and therefore the actuator 3A) is elastically supported from the outer periphery by the spiral spring 37C. Also, as shown in Fig. 26, the spiral spring 37C is disposed between the base end portion 34 of the actuator 3A and the flange portion 31f, similar to the wires 371, 372, 373, and 374 of the above embodiment.

[0067] Even in this third modified example, if the tip end 30 of the actuator 3A is misaligned with respect to the actuator insertion hole 20 of the switch body 2 (see Figure 8 of the above embodiment), the misalignment is absorbed by movement of the base end 34 of the actuator 3A via the ball bearing (see Figures 25 and 26). Not only can the misalignment of the actuator 3A with respect to the actuator insertion hole 20 be absorbed in any direction (arrow B direction) intersecting the actuator insertion direction (arrow A direction), but since the base end 34 is supported via a ball bearing, the base end 34 can be reliably supported by the ball bearing when an excessive thrust load acts on the base end 34 when the actuator 3A is inserted.

[0068] Furthermore, when the tip 30 of the actuator 3A is inserted into the switch body 2 while being displaced upward (see Figure 15 of the above embodiment), the tip 30 and the base end 34 move downward, causing the shaft 31 to move downward as well. At this time, an elastic repulsive force caused by the elastic deformation of the spiral spring 37C acts upward on the outer peripheral surface of the shaft 31 (see Figure 27).

[0069] Therefore, when the movable door is opened and tip portion 30 of actuator 3A tries to leave actuator insertion hole 20 of switch body 2 as the movable door moves, shaft portion 31 (and therefore actuator 3A) tries to move upward due to the elastic repulsive force of spiral spring 37C acting on shaft portion 31. At this time, since base end portion 34 of actuator 3A is movable by the ball bearing, actuator 3A moves upward smoothly.

[0070] 27, the actuator 3A is displaced upward relative to the actuator insertion hole 20, and the shaft 31 of the actuator 3A elastically deforms the spiral spring 37C downward when absorbing the displacement, but in the case of a downward displacement, the shaft 31 elastically deforms the spiral spring 37C upward, and in the case of a left-right displacement, the shaft 31 elastically deforms the spiral spring 37C leftward or rightward. In the third modified example, one end of the spiral spring 37C on the inner periphery side is engaged with the shaft 31 of the actuator 3A, and the other end on the outer periphery side is engaged with the base main body 32, and when the shaft 31 tries to rotate during the movement of the actuator 3A, the spiral spring 37C is twisted and its elastic restoring force acts on the shaft 31, thereby restricting the rotation of the shaft 31.

[0071] [Fourth Modification] 28 to 31 show a fourth modified example of the present invention (particularly a modified example of the first elastic support member), and in each figure, the same reference numerals as those in the above embodiment and the first to third modified examples indicate the same or corresponding parts. In the above embodiment, four wires each extending linearly are used, and the wires 371, 372, 373, and 374 are arranged in a lattice pattern in the vertical and horizontal directions (see Figs. 4 and 6), but in this fourth modified example, four tension coil springs 37C1, 37C2, 37C3, and 37C4 are used as the first elastic support member.

[0072] 28, the tension coil springs 37C1 and 37C2 are arranged linearly in the left-right direction above the shaft portion 31 of the actuator 3A, and the tension coil springs 37C3 and 37C4 are arranged linearly in the left-right direction below the shaft portion 31, with the tension coil springs 37C1 and 37C2 arranged parallel to the tension coil springs 37C3 and 37C4. A hook portion at one end of the tension coil spring 37C1 is engaged with a support 361 of the base main body 32, and a hook portion at the other end is engaged with a locking projection 31a protruding radially outward from the shaft portion 31. Similarly, a hook portion at one end of the tension coil spring 37C2 is engaged with a support 362 of the base main body 32, and a hook portion at the other end is engaged with a locking projection 31a of the shaft portion 31. A hook portion at one end of the tension coil spring 37C3 is engaged with a support 363 of the base body 32, and the hook portion at the other end is engaged with a locking projection 31b protruding radially outward from the shaft portion 31. A hook portion at one end of the tension coil spring 37C4 is engaged with a support 364 of the base body 32, and the hook portion at the other end is engaged with a locking projection 31b of the shaft portion 31.

[0073] As a result, the shaft portion 31 (and therefore the actuator 3A) is elastically supported from the outer periphery by the tension coil springs 37C1, 37C2, 37C3, and 37C4. As shown in Fig. 30, the tension coil springs 37C1, 37C2, 37C3, and 37C4 are disposed between the base end portion 34 of the actuator 3A and the flange portion 31f, similar to the wires 371, 372, 373, and 374 of the above embodiment.

[0074] Even in this fourth modified example, if the tip end 30 of the actuator 3A is misaligned with respect to the actuator insertion hole 20 of the switch body 2 (see Figure 8 of the above embodiment), the misalignment is absorbed by movement of the base end 34 of the actuator 3A via the ball bearing (see Figures 29 and 30). Not only can the misalignment of the actuator 3A with respect to the actuator insertion hole 20 be absorbed in any direction (arrow B direction) intersecting the actuator insertion direction (arrow A direction), but since the base end 34 is supported via a ball bearing, the base end 34 can be reliably supported by the ball bearing when an excessive thrust load acts on the base end 34 when the actuator 3A is inserted.

[0075] Furthermore, when the tip 30 of the actuator 3A is inserted into the switch body 2 in an upwardly displaced state (see FIG. 15 of the above embodiment), the tip 30 and the base end 34 move downward, causing the shaft 31 to move downward as well, at which time the upper tension coil springs 37C1 and 37C2 are tensilely deformed, and the lower tension coil springs 37C3 and 37C4 are tensilely deformed (see FIG. 31). At this time, an elastic repulsive force caused by the elastic deformation of the tension coil springs 37C1, 37C2, 37C3 and 37C4 acts upward on the shaft 31 from its outer periphery.

[0076] Therefore, when the movable door is opened and the tip portion 30 of the actuator 3A tries to leave the actuator insertion hole 20 of the switch body 2 as the movable door moves, the shaft portion 31 (and therefore the actuator 3A) tries to move upward due to the elastic repulsive forces of the tension coil springs 37C1, 37C2, 37C3, and 37C4 acting on the shaft portion 31. At this time, the base end portion 34 of the actuator 3A is movable by the ball bearings, so the upward movement of the actuator 3A is performed smoothly.

[0077] In addition, in FIG. 31, an example has been described in which the actuator 3A is misaligned upward with respect to the actuator insertion hole 20, and as a result, the upper and lower tension coil springs 37C1, 37C2, 37C3, and 37C4 undergo tensile deformation when the misalignment is absorbed, but in the case of a downward misalignment, the upper and lower tension coil springs 37C1, 37C2, 37C3, and 37C4 similarly undergo tensile deformation; in the case of a leftward misalignment, the right-side tension coil springs 37C1 and 37C4 undergo compressive deformation and the left-side tension coil springs 37C2 and 37C3 undergo tensile deformation; and in the case of a rightward misalignment, the left-side tension coil springs 37C2 and 37C3 undergo compressive deformation and the right-side tension coil springs 37C1 and 37C4 undergo tensile deformation. In addition, in this fourth modified example, the tension coil springs 37C1, 37C2 are engaged with the locking projection 31a of the shaft portion 31, and the tension coil springs 37C3, 37C4 are engaged with the locking projection 31b of the shaft portion 31. When the shaft portion 31 attempts to rotate on its axis during movement of the actuator 3A, elastic restoring forces caused by the deformation of each of the tension coil springs 37C1, 37C2, 37C3, and 37C4 act on the shaft portion 31, thereby restricting the rotation of the shaft portion 31.

[0078] [Fifth Modification] 32 to 35 show a fifth modified example of the present invention (particularly a modified example of the first elastic support member), and in each figure, the same reference numerals as those in the above embodiment and the first to fourth modified examples indicate the same or corresponding parts. In the above embodiment, four wires each extending linearly are used, and the wires 371, 372, 373, 374 are arranged in a lattice pattern in the vertical and horizontal directions (see Figs. 4 and 6). In this fifth modified example, two endless rubber bands 3 are used as the first elastic support member. 7 1, 3 7 2 is used.

[0079] As shown in Fig. 32, rubber band 371 is wound around four support columns 361 of base body 32 from the outer periphery and arranged in a rectangular shape that is long in the up-down direction. Similarly, rubber band 372 is wound around four support columns 362 of base body 32 from the outer periphery and arranged in a rectangular shape that is long in the left-right direction. Rubber band 371 is disposed on the front side of the paper surface of Fig. 32 with respect to rubber band 372. Each of rubber bands 371, 372 elastically abuts against the outer periphery surface of shaft portion 31, and shaft portion 31 (and therefore actuator 3A) is elastically supported from the outer periphery by each of rubber bands 371, 372.

[0080] As shown in FIG. 34, the rubber bands 371, 372 are disposed between the base end portion 34 of the actuator 3A and the flange portion 31f, similar to the wires 371, 372, 373, 374 of the above embodiment.

[0081] Even in this fifth modified example, if the tip end 30 of the actuator 3A is misaligned with respect to the actuator insertion hole 20 of the switch body 2 (see Figure 8 of the above embodiment), the misalignment is absorbed by movement of the base end 34 of the actuator 3A via the ball bearing (see Figures 33 and 34). Not only can the misalignment of the actuator 3A with respect to the actuator insertion hole 20 be absorbed in any direction (arrow B direction) intersecting the actuator insertion direction (arrow A direction), but since the base end 34 is supported via a ball bearing, the base end 34 can be reliably supported by the ball bearing when an excessive thrust load acts on the base end 34 when the actuator 3A is inserted.

[0082] Furthermore, when the tip 30 of the actuator 3A is inserted into the switch body 2 in a state where it is displaced upward (see FIG. 15 of the above embodiment), the tip 30 and the base end 34 move downward, causing the shaft 31 to move downward as well, and at this time, the shaft 31 comes into contact with the lower span of the rubber band 372, elastically deforming it downward (see FIG. 35). Therefore, at this time, an elastic repulsive force caused by the elastic deformation of the lower span of the rubber band 372 acts upward on the outer circumferential surface of the shaft 31.

[0083] Therefore, when the movable door is opened and the tip portion 30 of the actuator 3A tries to leave the actuator insertion hole 20 of the switch body 2 as the movable door moves, the shaft portion 31 (and therefore the actuator 3A) tries to move upward due to the elastic repulsive force of the lower span of the rubber band 372 acting on the shaft portion 31. At this time, the base end portion 34 of the actuator 3A is movable by the ball bearing, so the upward movement of the actuator 3A is performed smoothly.

[0084] In Figure 35, an example has been described in which actuator 3A is misaligned upward with respect to actuator insertion hole 20, and when the misalignment is absorbed, shaft 31 of actuator 3A abuts against the lower span of rubber band 372, elastically deforming the lower span downward. In the case of a downward misalignment, shaft 31 abuts against the upper span of rubber band 372, elastically deforming the upper span upward, and in the case of a left / right misalignment, shaft 31 abuts against the left or right span of rubber band 371, elastically deforming these spans to the left or right in Figure 32.

[0085] [Sixth Modification] 36 to 39 show a sixth modified example of the present invention (particularly a modified example of the first elastic support member), and in each drawing, the same reference numerals as those in the above-described embodiment and the first to fifth modified examples indicate the same or corresponding parts. In the above-described embodiment, an example was shown in which the wires 371, 372, 373, and 374 were provided inside the base portion 3B (see FIG. 5), but in this sixth modified example, the first elastic support member is provided outside the base portion 3B.

[0086] As shown in FIG. 36 and FIG. 37, in the actuator unit 3, a rubber cover 4 is attached to the front end surface 32A and the side surface 32B of the base body 32 of the base part 3B. The cover 4 has a bellows-shaped part (first elastic support member) 40 on the front end surface 32A of the base body 32, in which a through hole 40a through which the shaft part 31 is inserted is formed in the center. The inner peripheral surface of the through hole 40a of the bellows-shaped part 40 is in close contact with the outer peripheral surface of the shaft part 31, and the shaft part 31 is elastically supported by the bellows-shaped part 40. The bellows-shaped part 40 is formed concentrically from the through hole 40a toward the outside, and is configured to apply an elastic repulsive force to the outer peripheral surface of the shaft part 31 by expanding and contracting. The bellows-shaped part 40 covers the through hole 32a formed in the front end surface 32A of the base body 32.

[0087] Even in this sixth modified example, if the tip end 30 of the actuator 3A is misaligned with respect to the actuator insertion hole 20 of the switch body 2 (see Figure 8 of the previous embodiment), the misalignment is absorbed by movement of the base end 34 of the actuator 3A via the ball bearing (see Figures 37 and 38). Not only can the misalignment of the actuator 3A with respect to the actuator insertion hole 20 be absorbed in any direction (arrow B direction) intersecting the actuator insertion direction (arrow A direction), but since the base end 34 is supported via a ball bearing, the base end 34 can be reliably supported by the ball bearing when an excessive thrust load acts on the base end 34 when the actuator 3A is inserted.

[0088] Furthermore, when the tip 30 of the actuator 3A is inserted into the switch body 2 in a state where it is displaced upward (see FIG. 15 of the above embodiment), the tip 30 and the base end 34 move downward, causing the shaft 31 to move downward as well, at which time the shaft 31 elastically deforms the bellows-like portion 40 downward (see FIG. 39). That is, in this case, the bellows-like region below the shaft 31 is compressively deformed, and the bellows-like region above the shaft 31 is tensilely deformed. Therefore, at this time, an elastic repulsive force due to the elastic deformation of the bellows-like portion 40 acts upward on the outer circumferential surface of the shaft 31.

[0089] Therefore, when the movable door is opened and the tip portion 30 of the actuator 3A tries to leave the actuator insertion hole 20 of the switch body 2 as the movable door moves, the shaft portion 31 (and therefore the actuator 3A) tries to move upward due to the elastic repulsive force of the bellows-shaped portion 40 acting on the shaft portion 31. At this time, the base end portion 34 of the actuator 3A is movable by the ball bearing, so the upward movement of the actuator 3A is performed smoothly.

[0090] In Figure 39, an example has been described in which actuator 3A is misaligned upward with respect to actuator insertion hole 20, and when the misalignment is absorbed, shaft portion 31 of actuator 3A elastically deforms bellows-shaped portion 40 downward. In the case of a downward misalignment, shaft portion 31 elastically deforms bellows-shaped portion 40 upward, and in the case of a left-right misalignment, shaft portion 31 elastically deforms bellows-shaped portion 40 to the left or right in Figure 36.

[0091] [Seventh Modification] 40 and 41 show a seventh modified example of the present invention, and in each drawing, the same reference numerals as those in the above-described embodiment and the above-described first to sixth modified examples indicate the same or corresponding parts.

[0092] As shown in FIG. 40, inside the base body 32 of the base portion 3B, an elastic structure (second elastic support portion) made of a compression spring or the like is provided behind the base end portion 34 of the actuator 3A (on the right side in the figure). Material ) 5 is provided, and a flat hard plate 39 is disposed between the elastic structure 5 and the base end 34. The balls 35 of the base end 34 abut against the front end surface of the hard plate 39, and one end of the elastic structure 5 abuts against the rear end surface. The other end of the elastic structure 5 abuts against the front end surface of the lid 33 of the base portion 3B. As a result, the base end 34 and hard plate 39 of the actuator 3A are elastically supported by the elastic structure 5 in the direction of arrow A, which is the actuator insertion direction.

[0093] Although not shown, in this seventh modified example, a first elastic support member shown in any one of the above-mentioned embodiment or the above-mentioned first to sixth modified examples is provided.

[0094] Even in this case, if the tip end 30 of the actuator 3A is misaligned with respect to the actuator insertion hole 20 of the switch body 2 (see Figure 8 of the above embodiment), the misalignment is absorbed by movement of the base end 34 of the actuator 3A via the ball bearing (see Figure 41). Not only can the misalignment of the actuator 3A with respect to the actuator insertion hole 20 be absorbed in any direction (arrow B direction) intersecting the actuator insertion direction (arrow A direction), but since the base end 34 is supported via a ball bearing, the base end 34 can be reliably supported by the ball bearing when an excessive thrust load acts on the base end 34 when the actuator 3A is inserted.

[0095] Furthermore, in this case, since the hard plate 39 on which each ball 35 of the base end 34 rolls is elastically supported in the thrust direction by the elastic structure 5, the excessive thrust load acting on the base end 34 when the actuator 3A is inserted can be more effectively absorbed by the elastic compression deformation of the elastic structure 5.

[0096] Furthermore, when the tip 30 of the actuator 3A is inserted into the switch body 2 in a misaligned state (see Figure 15 of the above embodiment), the tip 30, the base end 34 and the shaft 31 move, and an elastic repulsive force caused by the elastic deformation of the first elastic member (not shown) acts on the actuator 3A.

[0097] Therefore, when the movable door is opened and the tip end 30 of the actuator 3A tries to leave the actuator insertion hole 20 of the switch body 2 as the movable door moves, the actuator 3A tries to move due to the elastic repulsive force of the first elastic member. At this time, the base end 34 of the actuator 3A is movable by the ball bearing, so the movement of the actuator 3A is smooth.

[0098] [Eighth Modification] Figures 42 and 43 show an eighth variant of the present invention (particularly a variant of the seventh variant), and in each figure, the same symbols as those in the above-mentioned embodiment and the first to seventh variants indicate the same or corresponding parts.

[0099] As shown in FIG. 42, in the eighth modified example, an arc-shaped (or bowl-shaped / dish-plate-shaped / disc-spring-shaped) hard plate 39' is provided instead of the flat hard plate 39 in the seventh modified example. The hard plate 39' has a concave arc-shaped surface 39'a on the front end side and a convex arc-shaped surface 39'b on the rear end side. The balls 35 of the base end 34 abut against the concave arc-shaped surface 39'a, and one end of the elastic structure 5 abuts against the convex arc-shaped surface 39'b. The other end of the elastic structure 5 abuts against the front end surface of the lid 33 of the base portion 3B. As a result, the base end 34 of the actuator 3A and the hard plate 39' are elastically supported by the elastic structure 5 in the actuator insertion direction A. Although not shown, the eighth modified example also has a first elastic support member as shown in any one of the above-mentioned embodiment or the first to sixth modified examples, as in the seventh modified example.

[0100] Even in this case, if the tip end 30 of the actuator 3A is misaligned with respect to the actuator insertion hole 20 of the switch body 2 (see Figure 8 of the above embodiment), the misalignment is absorbed by movement of the base end 34 of the actuator 3A via the ball bearing (see Figure 43). Not only can the misalignment of the actuator 3A with respect to the actuator insertion hole 20 be absorbed in any direction (arrow B direction) intersecting the actuator insertion direction (arrow A direction), but since the base end 34 is supported via a ball bearing, the base end 34 can be reliably supported by the ball bearing when an excessive thrust load acts on the base end 34 when the actuator 3A is inserted.

[0101] Furthermore, in this case, the hard plate 39' on which the balls 35 of the base end 34 roll is elastically supported in the thrust direction by the elastic structure 5, so that the excessive thrust load acting on the base end 34 when the actuator 3A is inserted can be effectively absorbed by the elastic compressive deformation of the elastic structure 5. Moreover, in this case, the base end 34 moves along the concave arc-shaped surface 39'a of the hard plate 39', and the amount of compressive deformation of the elastic structure 5 becomes large on the side to which the base end 34 has moved (FIG. 43). Therefore, when the actuator 3A returns to its original position, in addition to the elastic repulsive force of the first elastic support member (not shown) acting on the actuator 3A, the elastic repulsive force of the elastic structure 5 acts on the actuator 3A via the hard plate 39', so that the actuator 3A can be smoothly returned to its original position.

[0102] [Ninth Modification] Figures 44 and 45 show a ninth variant of the present invention (particularly a variant of the first elastic support member), and in each figure, the same symbols as those in the above-mentioned embodiment and the first to eighth variants indicate the same or corresponding parts.

[0103] As shown in Fig. 44, the first elastic support member 37 according to the ninth modification is composed of a cylindrical portion 37A arranged on the inner periphery side and a protruding portion 37B protruding obliquely forward from the rear end (the right end in the figure) of the cylindrical portion 37A, and the cylindrical portion 37A and the protruding portion 37B are formed in an approximately V-shaped axial cross section. The inner periphery surface 37Aa of the cylindrical portion 37A is in close contact with the outer periphery surface of the shaft portion 31 between the base end portion 34 of the shaft portion 31 and the flange portion 31f. The outer periphery edge portion of the protruding portion 37B abuts against the inner wall surface of the base body 32. With this configuration, the shaft portion 31 (and therefore the actuator 3A) is elastically supported from the outer periphery side by the first elastic support member 37.

[0104] Even in this ninth modified example, if the tip end 30 of the actuator 3A is misaligned with respect to the actuator insertion hole 20 of the switch body 2 (see Figure 8 of the above embodiment), the misalignment is absorbed by movement of the base end 34 of the actuator 3A via the ball bearing (see Figure 45). Not only can the misalignment of the actuator 3A with respect to the actuator insertion hole 20 be absorbed in any direction (arrow B direction) intersecting the actuator insertion direction (arrow A direction), but since the base end 34 is supported via a ball bearing, the base end 34 can be reliably supported by the ball bearing when an excessive thrust load acts on the base end 34 when the actuator 3A is inserted.

[0105] Furthermore, when the tip 30 of the actuator 3A is inserted into the switch body 2 in a state where it is displaced upward (see FIG. 15 of the above embodiment), the tip 30 and the base end 34 move downward, causing the shaft 31 to also move downward, and at this time, the shaft 31 elastically deforms the protruding portion 37B in the lower region of the first elastic support member 37 (see FIG. 45). Therefore, at this time, an elastic repulsive force caused by the elastic deformation of the protruding portion 37B in the lower region of the first elastic support member 37 acts upward on the outer circumferential surface of the shaft 31.

[0106] Therefore, when the movable door is opened and the tip portion 30 of the actuator 3A tries to leave the actuator insertion hole 20 of the switch body 2 as the movable door moves, the shaft portion 31 (and therefore the actuator 3A) tries to move upward due to the elastic repulsive force of the protruding portion 37B in the lower region of the first elastic support member 37 acting on the shaft portion 31. At this time, the base end portion 34 of the actuator 3A is movable by the ball bearing, so the actuator 3A moves upward smoothly.

[0107] In Figure 45, an example has been described in which the actuator 3A is displaced upward relative to the actuator insertion hole 20, and when the displacement is absorbed, the shaft 31 of the actuator 3A elastically deforms the protrusion 37B in the lower region of the first elastic support member 37. In the case of a downward displacement, the shaft 31 elastically deforms the protrusion 37B in the upper region of the first elastic support member 37, and in the case of a left-right displacement, the shaft 31 elastically deforms the protrusion 37B in the left or right region of the first elastic support member 37 to the left or right.

[0108] [Tenth Modification] Figures 46 to 52 are diagrams for explaining a safety switch including an actuator unit and a switch body according to a tenth modified example of the present invention. Figure 46 is a schematic diagram of the safety switch (corresponding to Figure 1 in the above embodiment), Figure 47 is a vertical cross-sectional view of the actuator unit (corresponding to Figure 5 in the above embodiment), Figures 48 to 50 are diagrams showing the movement of the actuator unit and the actuator in time series when the actuator unit is misaligned with respect to the actuator insertion hole of the switch body (corresponding to Figures 8 to 10 in the above embodiment), Figure 51 is a vertical cross-sectional view of the actuator unit after the actuator has moved (corresponding to Figure 13 in the above embodiment), and Figure 52 is a diagram showing a state in which the actuator is inserted into the switch body and the locking member inside the switch body is locked to the actuator (corresponding to Figure 15 in the above embodiment). In each figure, the same reference numerals as those in the above embodiment indicate the same or corresponding parts.

[0109] In this tenth modified example, the shape of the actuator is different from that of the above-mentioned embodiment. In the above-mentioned embodiment, the shaft portion 31 of the actuator 3A has a cylindrical shape (i.e., a circular cross section) and the tip portion 30 has a hemispherical shape with a convex arc-shaped surface 30a at the tip, but in the tenth modified example, the shaft portion 31' of the actuator 3A' is plate-shaped (see Figs. 50 and 52) (i.e., a rectangular cross section) and has a rounded portion (i.e., a convex arc-shaped surface) 31'r at the corner of the flat tip portion 31'a. In addition, a rectangular locking hole 31'b, for example, is formed in the area near the tip portion 31'a of the shaft portion 31', penetrating the shaft portion 31' in the thickness direction.

[0110] 47 and 51, in this tenth modified example, the wires 371-374 in the above-described embodiment are used as the first elastic support member, but other members as shown in the above-described modified examples may be used as the first elastic support member. Also, since the shaft portion 31' of the actuator 3A' is plate-shaped, the opening 32a formed in the front end surface of the base body 32 of the base portion 3B may be rectangular rather than circular.

[0111] As shown in FIG. 46, the center line 3C of the actuator 3A' L is the center line 2C of the actuator insertion hole 20 of the switch body 2 L If they coincide with each other, then when the actuator is inserted, the tip portion 31'a of the actuator 3A' does not interfere with the tapered surface 20a of the actuator insertion hole 20, and the actuator can be smoothly inserted into the actuator insertion hole 20.

[0112] On the other hand, as shown in FIG. 48, the center line 3C of the shaft portion 31′ (i.e., the actuator 3A′) L is the center line 2C of the actuator insertion hole 20 of the switch body 2 LWhen the actuator 3A' is misaligned with respect to the actuator insertion hole 20, the rounded portion 31'r of the tip portion 31'a of the actuator 3A' abuts against the tapered surface 20a of the actuator insertion hole 20 during insertion of the actuator (see FIG. 49). As a result, while the movable door is closed, the rounded portion 31'r of the tip portion 31'a attempts to move obliquely downward as shown in the figure while sliding on the tapered surface 20a along the tapered surface 20a.

[0113] At this time, as shown in Figure 47, the balls 35 protruding from the rear end surface of the base end 34 of the actuator 3A' are movable in the direction of arrow B along the inner surface of the lid body 33, so that when a force is applied to move the tip end 31'a of the actuator 3A' downward while the movable door is closed, as shown in Figure 51, the balls 35 roll on the inner surface of the lid body 33, causing the base end 34 to move downward along the inner surface of the lid body 33. This causes the actuator 3A' to move downward relative to the base part 3B.

[0114] As a result, the rounded portion 31'r of the tip portion 31'a of the actuator 3A' moves obliquely downward in FIG. 49 along the tapered surface 20a of the actuator insertion hole 20, and as shown in FIG. 50, the actuator 3A' is inserted into the inside of the switch body 2 through the actuator insertion hole 20. Then, as shown in FIG. 52, a locking member (e.g., a cam member) SR inside the switch body 2 locks the locking hole 31'b of the shaft portion 31' of the actuator 3A'. This locks the actuator 3A' and prevents it from coming off. From this state, the contacts (not shown) inside the switch body 2 switch, and the operation of a machine such as a robot begins.

[0115] In this tenth modified example, similarly to the above embodiment, when a positional deviation occurs, the base end 34 of the actuator 3A' can move via the ball bearing to absorb the positional deviation, and can also absorb a positional deviation in any direction (arrow B direction) intersecting with the actuator insertion direction (arrow A direction). Furthermore, the ball bearing can reliably support an excessive thrust load acting on the base end 34 of the actuator 3A' when a positional deviation occurs. Furthermore, by using a ball bearing, the coefficient of friction can be reduced, further improving durability. As in the previous embodiment, the actuator 3A' returns to its original position due to the elastic repulsive force generated by the elastic deformation of the wires 371-374. However, in this tenth modification, since the shaft 31' of the actuator 3A' has a rectangular cross section, it is preferable to restrict the rotation of the shaft 31' so that the shaft 31' can be inserted into the actuator insertion hole 20 and locked into the locking hole 31'b by the locking member SR after insertion more smoothly. In this respect, the wires 371-374 clamp the shaft 31' from above, below, left and right (see the twelfth modification (FIG. 54) described later). As a mechanism for restricting the rotation of the shaft 31', the mechanism according to the third modification (FIG. 24) or the fourth modification (FIG. 28) described above may be adopted.

[0116] [Eleventh Modification] In the above embodiment, an example was shown in which the base end portion 34 of the actuator 3A holds five balls 35 (see Figs. 4 and 12), but application of the present invention is not limited to this. The number of balls 35 may be more or less than five. Fig. 53 shows an eleventh modified example of the present invention, which corresponds to Fig. 4 of the above embodiment, but Fig. 53 shows only the rear end surface of the base end portion 34.

[0117] 53, the base end 34 of the actuator 3A has five balls 35 arranged at equal or approximately equal intervals on the circumference, and one ball 35 arranged at the center or approximately the center. Various other arrangements are possible for the balls 35, and the sizes of the balls 35 do not necessarily have to be the same.

[0118] In the above embodiment, the bottom of the holding hole 34a for the ball 35 is formed in a tapered shape (see FIG. 5), but the application of the present invention is not limited to this. The bottom of the holding hole 34a may be flat. The shape of the holding hole 34a does not necessarily have to be circular, and may be elliptical / elliptical / oval, or polygonal, and further, one holding hole 34a may hold multiple balls 35.

[0119] In the above embodiment, the holding hole 34a is formed directly in the base end 34, but the application of the present invention is not limited to this. A thin-walled holding tool may be manufactured from a material with a low friction coefficient, and the holding tool may be fitted and fixed into a larger holding hole 34a, so that the ball 35 is held by the holding tool so as to be free to rotate.

[0120] In the above embodiment, the ball 35 is held at the base end 34, but the application of the present invention is not limited to this. The cover 33 may be made thick and a plurality of holding holes may be formed therein to hold the balls rotatably, and the rear end surface of the base end 34 may be made flat so that the balls come into contact with the rear end surface of the base end 34.

[0121] [Twelfth Modification] Fig. 54 shows an actuator unit according to a twelfth modified example of the present invention, and corresponds to Fig. 6 of the above embodiment. In the above embodiment, an example was shown in which the shaft 31 of the actuator 3A had a circular cross section, but the shaft 31 may have a rectangular cross section. In the example shown in Fig. 54, a shaft 31A having a square cross section is shown. As shown in the figure, wires 371-374 are in contact with the four faces of the shaft 31A, respectively, so that the rotation of the shaft 31A is restricted when the actuator 3A moves when the actuator is inserted in the event of misalignment.

[0122] [Thirteenth Modification] FIG. 55 shows an actuator unit according to a thirteenth modified example of the present invention, and corresponds to FIG. 16 of the first modified example. In the first modified example, the actuator 3 A In the example shown in Fig. 55, the shaft portion 31 has a circular cross section, but the shaft portion 31 may have a rectangular cross section. In the example shown in Fig. 55, the shaft portion 31B has a square cross section. As shown in the figure, the movable arms 371-374 of the torsion coil springs 37C1-37C4 are in contact with the four faces of the shaft portion 31B. This restricts the rotation of the shaft portion 31B when the actuator 3A moves when the actuator is inserted in the event of misalignment.

[0123] [Modification 14] Fig. 56 shows an actuator unit according to a fourteenth modification of the present invention, and corresponds to Fig. 32 of the fifth modification. In the fifth modification, the actuator 3 A In the above example, the shaft 31 has a circular cross section, but the shaft 31 may have a rectangular cross section. In the example shown in Fig. 56, a shaft 31C having a square cross section is shown. As shown in the figure, rubber bands 371, 372 are in contact with the four faces of the shaft 31C, respectively. This restricts the rotation of the shaft 31C when the actuator 3A moves when the actuator is inserted in the event of misalignment.

[0124] [Fifteenth Modification] In the tenth modified example, the actuator insertion hole 20 of the switch body 2 has a tapered surface 20a, and the corners of the tip 31'a of the actuator 3A' have a rounded portion (i.e., a convex arc-shaped surface) 31'r, but the application of the present invention is not limited to this. The actuator insertion hole 20 may have a convex arc-shaped surface, and the corners of the tip 31'a of the actuator 3A' may have a chamfered portion (i.e., an inclined surface).

[0125] [Modification 16] The tapered surface 20a (FIG. 1) provided in the actuator insertion hole 20 of the switch body 2 may be extended (not shown) to a position adjacent to the locking member SR (FIG. 7) inside the switch body 2. In this case, even if the actuator 3A is displaced in either or both the up-down direction and the left-right direction, when the actuator 3A moves along the tapered surface 20a to a position adjacent to the locking member SR, the displacement of the actuator 3A is eliminated, and this makes it possible to reliably lock the actuator 3A with the locking member SR.

[0126] [Seventeenth Modification] In the above embodiment, an example was shown in which the shaft portion 31 of the actuator 3A had a smaller diameter than the hemispherical tip portion 30, but the application of the present invention is not limited to this. The shaft portion 31 may have substantially the same diameter as the tip portion 30, and a recess or a recessed groove / circumferential groove (not shown) having a smaller diameter than the tip portion 30 and the shaft portion 31 may be formed between the tip portion 30 and the shaft portion 31, and the locking member SR may be locked in these recesses or the like. Alternatively, in the above embodiment, a large diameter portion having substantially the same diameter as the tip portion 30 and a larger diameter than the shaft portion 31 may be provided at a longitudinal intermediate position of the small diameter shaft portion 31, with a gap (functioning as a locking recess for the locking member SR) between the tip portion 30 and the small diameter shaft portion 31.

[0127] In these cases, after the tip 30 of the actuator 3A enters the inside of the switch body 2, the shaft portion 31 or the large diameter portion, which has substantially the same diameter as the tip 30, abuts against the tapered surface 20a of the actuator insertion hole 20 and enters the inside of the switch body 2 along the tapered surface 20a. Therefore, even if the actuator 3A is misaligned in either the up-down or left-right direction or both, when the actuator 3A moves to the position of the locking member SR, the misalignment of the actuator 3A is eliminated, and this makes it possible to reliably lock the actuator 3A by the locking member SR.

[0128] [Other Modifications] The above-described embodiment and each modification should be considered in all respects as merely illustrative of the present invention, and not restrictive. Those skilled in the art to which the present invention pertains may, when considering the teachings above, construct various modifications and other embodiments that incorporate the principles of the present invention without departing from the spirit and essential characteristics of the present invention, even if not expressly described herein. [Industrial Applicability]

[0129] The present invention is useful for an actuator unit and a safety switch including the actuator unit. [Explanation of symbols]

[0130] 1: Safety switch 2: Switch body 20: Actuator insertion hole 3: Actuator unit 3A, 3A': Actuator 30, 31'a: tip 30a: Convex arc surface 31, 31': Shaft 31'b: Locking hole 31'r: R section (convex arc surface) 32a: Open hole 34: Base end (holding part) 34a: Retaining hole 35: Ball 3B: Base section 371 to 374: Wire (first elastic support member) 37C1 to 37C4: Torsion coil spring / tension coil spring (first elastic support member) 371, 372: Rubber band 37C: Spiral spring (first elastic support member) 39': Arc-shaped rigid plate (arc-shaped plate member) 39'a: Concave arc surface 40: bellows-like portion (first elastic support member) 5: Elastic structure (second elastic support) SR: Locking member A: Actuator insertion direction B: Intersecting direction with actuator insertion direction [Prior art documents] [Patent documents]

[0131] [Patent Document 1] JP 2017-91877 A (see paragraphs

[0037] ,

[0038] ,

[0044] , Fig. 1, Fig. 13 to Fig. 15) [Patent Document 2] JP-A-8-138500 (see paragraphs

[0009] ,

[0020] , and Figures 1 to 3) [Patent Document 3] JP-A-11-317132 (see claim 1, paragraphs

[0011] ,

[0012] , Figs. 1, 3, and 4)

Claims

1. An actuator unit comprising: an actuator having a tip portion that can be inserted into the actuator insertion hole; a base portion that supports a base end portion of the actuator via a ball bearing so as to be freely movable in any direction intersecting an insertion direction of the actuator into the actuator insertion hole, a positional deviation between the tip end of the actuator and the actuator insertion hole is absorbed in any direction by movement of the base end of the actuator via the ball bearing; 1. An actuator unit comprising:

2. In claim 1, the base end of the actuator has a holding portion that rotatably holds a plurality of balls, and the balls and the holding portion constitute the ball bearing; 1. An actuator unit comprising:

3. In claim 1, The tip portion has a convex arcuate surface or an inclined surface.

1. An actuator unit comprising:

4. In claim 1, The base portion is provided with a first elastic support member that elastically supports the actuator from an outer periphery thereof.

1. An actuator unit comprising:

5. In claim 1, the actuator has a shaft portion extending between the tip portion and the base portion, and the base portion has an opening through which the shaft portion is inserted to allow the movement of the base portion.

1. An actuator unit comprising:

6. In claim 5, A step is formed between the shaft portion and the tip portion.

1. An actuator unit comprising:

7. In claim 5, a first elastic support member is provided on the base portion to elastically support the shaft portion of the actuator from an outer periphery thereof; 1. An actuator unit comprising:

8. In claim 7, The first elastic support member covers the opening.

1. An actuator unit comprising:

9. In claim 1, The actuator has a locking hole that is engaged with a locking member inside a switch body having the actuator insertion hole.

1. An actuator unit comprising:

10. In claim 1, a second elastic support member that elastically supports the base end of the actuator in the insertion direction of the actuator is provided on the base portion; 1. An actuator unit comprising:

11. In claim 10, a circular arc-shaped plate member having a concave circular arc surface forming a rolling surface of the ball bearing is provided on the base portion, and the circular arc-shaped plate member is elastically supported by the second elastic support member; 1. An actuator unit comprising:

12. The actuator unit according to claim 1 ; a switch body having the actuator insertion hole; With safety switch.

Images