Padlock-compatible emergency stop switch and safety control system including same

Abstract

To improve safety by preventing a user from forgetting to lock a padlock or reducing the risk of carelessly resetting an emergency stop state in a padlock-compatible emergency stop switch.SOLUTION: The emergency stop switch 1 coping with the padlock has through-holes 21a, 30a, and 30b for inserting the padlock 100, and detects by a circuit C2 that the respective insertion holes 21a, 30a, and 30b are aligned and the padlock 100 is to be inserted or has been inserted (that is, in an insertable state).SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a padlock-compatible emergency stop switch and a safety control system equipped with the same, and to an improvement in the structure thereof. [Background technology]

[0002] Generally, an emergency stop switch has a push button that can be pressed by an operator and contacts that are made and broken when the push button is pressed (see Figure 1 of JP 2001-35302 A). When the emergency stop switch is pressed, the contacts switch from an ON state to an OFF state, cutting off the electrical circuit of the device and bringing the device to an emergency stop.

[0003] In such emergency stop switches, in order to prevent a third party from inadvertently resetting the push button after it has been pressed, a switch with a padlock, as shown in Japanese Patent Laid-Open Publication No. 2006-49176, i.e., a padlock-compatible emergency stop switch, has been proposed.

[0004] As shown in Figures 2 and 8 of JP 2006-49176 A, the padlock-compatible emergency stop switch includes a push button (13) that can be pressed and rotated, a flange (3) disposed around the push button (13), and a contact portion (2) that turns on / off when the push button (13) is operated (see paragraphs

[0025] to

[0027] of the same publication). Two through-hole lock holes (13e) are formed on the side of the push button (13) (see paragraph

[0033] of the same publication). Meanwhile, four lock holes (31a) are formed in the side plate (31) of the flange (3) (see paragraph

[0034] of the same publication). Before the push button (13) is pressed, the through-hole lock holes (13e) and the lock holes (31a) do not completely overlap, as shown in Figure 7 (see paragraph

[0035] of the same publication).

[0005] Next, when the push button (13) is pressed, the contact portion (2) goes into the OFF state, and immediately thereafter, the rotation restriction on the push button (13) is released and the push button (13) starts to rotate, and at the end of the rotation, all of the through-holes (13e) of the push button (13) are aligned with the lock holes (31a) of the flange (3) as shown in Fig. 11 (see paragraph

[0039] of the same publication). From this state, as shown in Fig. 12, the hasp (41) of the padlock (4) is inserted into the through-holes (13e) of the push button (13) through the lock holes (31a) of the flange (3), and then protrudes out through the other lock hole (31a) of the flange (3) to lock, thereby completing the lockout (see paragraph

[0040] of the same publication). Summary of the Invention [Problem to be solved by the invention]

[0006] In the above-mentioned padlock-compatible emergency stop switch, after the through-hole lock hole (13e) of the push button (13) is aligned with the lock hole (31a) of the flange (3), whether or not to lock the through-hole lock hole (13e) and the lock hole (31a) by inserting the hasp (41) of the padlock (4) into them is left to the discretion of the operator, and even if the operator is given thorough safety training, there is a risk that the padlock may be forgotten to be locked.

[0007] Furthermore, with conventional padlock-compatible emergency stop switches, some types require the operator to further operate the push button to align the padlock insertion holes after pressing the push button to effect an emergency stop. With these types of emergency stop switches, the risk of the push button being inadvertently reset after an emergency stop differs depending on whether the push button is only pressed to effect an emergency stop or whether the push button is then further operated to align the padlock insertion holes to attach a padlock. In the former case, the push button is only pressed, so there is a high risk of the push button being inadvertently reset, but in the latter case, the push button is further operated after being pressed, so two actions (i.e., two operations) are required to reset the push button, reducing the risk of the push button being inadvertently reset.

[0008] The present invention has been made in consideration of the above-mentioned conventional circumstances, and the problem to be solved by the present invention is to improve safety by preventing forgetting to lock a padlock in a padlock-compatible emergency stop switch. Another object of the present invention is to provide a padlock-compatible emergency stop switch that can improve safety by reducing the risk of the emergency stop state being inadvertently reset. Furthermore, the present invention aims to provide a safety control system that includes such a padlock-compatible emergency stop switch and can monitor whether the padlock is attached. [Means for solving the problem]

[0009] The padlock-compatible emergency stop switch of the present invention has at least two insertion holes for inserting a padlock, and a detection means detects whether the insertion holes are aligned and the padlock is ready to be inserted or has been inserted.

[0010] According to the present invention, the detection means detects that at least two insertion holes for inserting padlocks are aligned and a padlock is ready to be inserted or that a padlock is already inserted. When the detection means detects that a padlock is inserted into each insertion hole, it can detect that a padlock has been inserted into each insertion hole, making it possible to monitor whether a padlock is attached, thereby preventing forgetting to lock a padlock and improving safety. Furthermore, when the detection means detects that the insertion holes are aligned and ready to insert a padlock, i.e., that a padlock can be inserted, it can detect that the insertion holes are aligned and ready to insert a padlock, making it possible to monitor whether the insertion holes are aligned, thereby reducing the risk of the emergency stop state being inadvertently reset and improving safety.

[0011] The padlock-compatible emergency stop switch of the present invention comprises a push button having a first insertion hole for inserting a padlock, a housing that supports the push button slidably and has a second insertion hole for inserting the padlock, and detection means that detects whether the first and second insertion holes are aligned when the push button is operated and the padlock is ready to be inserted or has been inserted.

[0012] According to the present invention, when the push button is operated, the first insertion hole for inserting a padlock on the push button side and the second insertion hole for inserting a padlock on the housing side are aligned, and the detection means detects that the padlock is ready to be inserted or that the padlock is already inserted. When the detection means detects that padlocks are inserted into the first and second insertion holes, it can detect that padlocks have been inserted into the first and second insertion holes, making it possible to monitor whether a padlock is installed, thereby preventing forgetting to lock the padlock and improving safety. Furthermore, when the detection means detects that the first and second insertion holes are aligned and ready to insert a padlock, i.e., that the padlock is ready to be inserted, it can detect that the first and second insertion holes are aligned and ready to insert a padlock, making it possible to monitor whether the first and second insertion holes are aligned, thereby reducing the risk of the emergency stop state being inadvertently reset and improving safety.

[0013] The padlock-compatible emergency stop switch of the present invention comprises a push button, an openable / closable cover having a third insertion hole for inserting a padlock and for covering the push button, a cover body having a fourth insertion hole for inserting a padlock and supporting the cover in an openable / closable or detachable manner, and a detection means for detecting that the third and fourth insertion holes are aligned and a padlock can be inserted by operating the push button or closing the cover.

[0014] According to this invention, by operating the push button or closing the cover, the detection means detects that the third insertion hole for inserting a padlock on the cover side and the fourth insertion hole for inserting a padlock on the cover main body side are aligned and ready for insertion of a padlock. This allows the detection means to detect that the third and fourth insertion holes are aligned and ready for insertion of a padlock, i.e., that a padlock is ready or available for insertion. Therefore, it becomes possible to monitor whether the third and fourth insertion holes are aligned, thereby reducing the risk of the emergency stop state being inadvertently reset and improving safety.

[0015] In the present invention, the detection means has a detection part that can take a shielding position that shields the insertion hole and an open position that opens the insertion hole, and when the shackle part of the padlock is inserted into the insertion hole, the shackle part presses the detection part, moving the insertion hole to the open position, thereby detecting that the padlock has been inserted.

[0016] In the present invention, the detection means has a detection unit that can take a shielding position that shields the insertion hole and an opening position that opens the insertion hole, and when the cover is closed, the cover presses the detection unit to move the insertion hole to the opening position, thereby detecting that the insertion holes are aligned.

[0017] In the present invention, the detection means is adapted to detect the shackle or body of the padlock when the padlock is inserted.

[0018] In the present invention, after the switch is turned off by pressing the push button, further operation of the push button transitions to a state in which the padlock can be inserted.

[0019] In the present invention, the operation after the push button is pressed is a push operation in which the push button is pressed in or a turn operation in which the push button is rotated.

[0020] The safety control system according to the present invention is equipped with the padlock-compatible emergency stop switch described above, and after an emergency stop is initiated by the emergency stop switch, entry into the danger zone in which the machine to be stopped is installed is permitted based on detection by the detection means.

[0021] According to the present invention, after an emergency stop, the vehicle is not allowed to enter the danger zone until it has been detected by the detection means, thereby improving safety. [Effects of the Invention]

[0022] As described above, according to the present invention, it is possible to prevent forgetting to lock the padlock, or to reduce the risk of the emergency stop state being inadvertently reset, thereby improving safety. [Brief explanation of the drawings]

[0023] [Figure 1] 1 is a schematic vertical cross-sectional view of a padlock-compatible emergency stop switch according to a first embodiment of the present invention; [Figure 2] 2 is a diagram for explaining the operation procedure of the emergency stop switch (FIG. 1) in chronological order. [Figure 3] 2 is a diagram for explaining the operation procedure of the emergency stop switch (FIG. 1) in chronological order. [Figure 4] 2 is a diagram for explaining the operation procedure of the emergency stop switch (FIG. 1) in chronological order. [Figure 5] 1A is a schematic longitudinal sectional view of a padlock-compatible emergency stop switch according to a second embodiment of the present invention, and FIG. 1B is a transverse sectional view taken along line BB thereof. [Figure 6] 5A and 5B are diagrams for explaining the operation procedure of the emergency stop switch (FIGS. 5A and 5B) in chronological order. [Figure 7] 5A and 5B are diagrams for explaining the operation procedure of the emergency stop switch (FIGS. 5A and 5B) in chronological order. [Figure 8] 5A and 5B are diagrams for explaining the operation procedure of the emergency stop switch (FIGS. 5A and 5B) in chronological order. [Figure 9] FIG. 10 is a schematic vertical cross-sectional view of a padlock-compatible emergency stop switch according to a third embodiment of the present invention. [Figure 10] 10 is a diagram for explaining the operation procedure of the emergency stop switch (FIG. 9) in chronological order. [Figure 11] 10 is a diagram for explaining the operation procedure of the emergency stop switch (FIG. 9) in chronological order. [Figure 12] FIG. 10 is an overall perspective view showing a specific structure of the emergency stop switch (FIG. 9). [Figure 13] FIG. 13 is an exploded view of the emergency stop switch (FIG. 12). [Figure 14] This shows the state after the padlock is attached to the emergency stop switch (Fig. 12). [Figure 15] FIG. 13 is a vertical cross-sectional view of the emergency stop switch (FIG. 12) taken along line XV-XV. [Figure 16] FIG. 10 is a schematic vertical cross-sectional view of a padlock-compatible emergency stop switch according to a fourth embodiment of the present invention. [Figure 17] 17A to 17C are diagrams for explaining the operation procedure of the emergency stop switch (FIG. 16) in chronological order. [Figure 18] 17A to 17C are diagrams for explaining the operation procedure of the emergency stop switch (FIG. 16) in chronological order. [Figure 19] 17A to 17C are diagrams for explaining the operation procedure of the emergency stop switch (FIG. 16) in chronological order. [Figure 20] 17A to 17C are diagrams for explaining the operation procedure of the emergency stop switch (FIG. 16) in chronological order. [Figure 21] FIG. 10 is a schematic vertical cross-sectional view of a padlock-compatible emergency stop switch according to a fifth embodiment of the present invention. [Figure 22] FIG. 10 is a schematic vertical cross-sectional view of a padlock-compatible emergency stop switch according to a sixth embodiment of the present invention. [Figure 23] 23 is a diagram for explaining the operation procedure of the emergency stop switch (FIG. 22) in chronological order. FIG. [Figure 24] 23 is a diagram for explaining the operation procedure of the emergency stop switch (FIG. 22) in chronological order. FIG. [Figure 25] FIG. 13 is a schematic vertical cross-sectional view of a padlock-compatible emergency stop switch according to a seventh embodiment of the present invention. [Figure 26] 26 is a diagram for explaining the operation procedure of the emergency stop switch (FIG. 25) in chronological order. [Figure 27] 26 is a diagram for explaining the operation procedure of the emergency stop switch (FIG. 25) in chronological order. [Figure 28] FIG. 13 is a schematic vertical cross-sectional view of a padlock-compatible emergency stop switch according to an eighth embodiment of the present invention. [Figure 29]28A to 28C are diagrams for explaining the operation procedure of the emergency stop switch (FIG. 28) in chronological order. [Figure 30] 28A to 28C are diagrams for explaining the operation procedure of the emergency stop switch (FIG. 28) in chronological order. [Figure 31] FIG. 13 is a schematic vertical cross-sectional view of a padlock-compatible emergency stop switch according to a ninth embodiment of the present invention. [Figure 32] FIG. 19 is a schematic vertical cross-sectional view of a padlock-compatible emergency stop switch according to a tenth embodiment of the present invention. [Figure 33] 32. FIG. 33 is a diagram for explaining the operating procedure of the emergency stop switch (FIG. 32). [Figure 34] FIG. 19 is a schematic vertical cross-sectional view of a padlock-compatible emergency stop switch according to an eleventh embodiment of the present invention. [Figure 35] 1 is a schematic block diagram of a safety control system employing a padlock-compatible emergency stop switch according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0024] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. [First Example] 1 to 4 are diagrams illustrating a padlock-compatible emergency stop switch according to a first embodiment of the present invention. FIG. 1 shows a schematic vertical cross-sectional configuration of the emergency stop switch, and FIGS. 2 to 4 show the operation procedure of the emergency stop switch in FIG. 1 in chronological order. The emergency stop switch is installed, for example, near the boundary (such as an entrance / exit) between a dangerous area where a machine is installed and a safety area outside of it in a factory (the same applies to the second to tenth embodiments below). In each figure, for ease of explanation, the left-right direction of the figure is referred to as the x-direction, the direction perpendicular to the plane of the figure is referred to as the y-direction, and the up-down direction of the figure is referred to as the z-direction. In other words, if the x and y directions are horizontal, the z-direction is vertical.

[0025] As shown in FIG. 1, a padlock-compatible emergency stop switch 1 according to this embodiment includes a push button 2 and a case (housing) 3 that slidably supports the push button 2 and accommodates a part of it.

[0026] The push button 2 has an operating unit 20 having an operating surface 20a on the front side for an operator to press, and a shaft 21 that is connected to the back side of the operating unit 20 and extends in the x direction (axial direction), with one through-hole (first insertion hole) 21a formed in the shaft 21 that extends in the z direction and opens onto the outer circumferential surface of the shaft 21. As will be described later, the through-hole 21a is a hole for inserting a padlock.

[0027] The case 3 has a cylindrical portion 30 that supports the shaft portion 21 of the push button 2 so that it can slide freely in the x direction (axial direction). The cylindrical portion 30 is formed with through holes (second insertion holes) 30a and 30b that extend in the z direction. The through holes 30a and 30b are holes for inserting padlocks, as will be described later. The center line 30a of the through hole 30a c and the center line 30b of the through hole 30b c The through holes 30a and 30b extend on the same straight line, and are arranged at positions opposite to each other when viewed from the z direction, and are aligned in the z direction. c , 30b c As shown in FIG. 1, when the push button 2 is in the initial position before being pressed, the center line 21a of the through hole 21a of the shaft 21 of the push button 2 is c It is offset, or shifted, by a certain amount in the x direction.

[0028] In this example, two (i.e., one set) opposing through holes 30a, 30b are formed in the cylindrical portion 30, but two or more sets (i.e., four or more) of these through holes may be provided. Furthermore, it is sufficient that at least one through hole on the cylindrical portion 30 side can be aligned with the through hole 21a on the push button 2 side (i.e., at least two in the entire emergency stop switch). For example, when the through hole 30a is used as the through hole on the cylindrical portion 30 side, a notch having a spatial area larger than the inner diameter of the through hole 30b may be provided in the cylindrical portion 30 at a position opposite the through hole 30a, instead of the other through hole 30b.

[0029] The case 3 has a mounting portion 31 for mounting to, for example, a panel P of a control panel (not shown) of a machine. A threaded portion (not shown) is formed on the outer periphery of the mounting portion 31, and the mounting portion 31 is inserted into a mounting hole Pa formed through the panel P, and is fastened to the panel P by a lock nut (not shown) that screws onto the threaded portion on the outer periphery of the mounting portion 31 from the back side of the panel P.

[0030] A circuit C1 having a fixed contact 32 and a circuit (detection means) C2 having a fixed contact 33 are provided inside the mounting portion 31. For convenience of illustration, elements other than the fixed contacts 32 and 33 are not shown in the circuits C1 and C2 (the same applies to the second to tenth embodiments described below). Meanwhile, an extension portion 22 extending in the x-direction from the back surface of the shaft portion 21 of the push button 2 is connected to the back surface of the shaft portion 21. A movable contact 23 is attached to the tip of the extension portion 22, and the movable contact 23 moves together with the push button 2 via the extension portion 22 and the shaft portion 21.

[0031] The operating procedure of the emergency stop switch 1 will be described with reference to FIGS. First, before the push button 2 is operated, i.e., before an emergency stop is performed, the operating surface 20a of the operating portion 20 of the push button 2 is located in the initial position (solid line position) as shown in Fig. 1. At this time, the through-hole 21a of the shaft portion 21 of the push button 2 is not aligned in the z direction with respect to the through-holes 30a, 30b of the cylindrical portion 30 of the case 3, but is offset. Also, the movable contact 23 is in contact with the fixed contact 32 of the circuit C1, and the circuit C1 is in the ON state. Meanwhile, the circuit C2 is in the OFF state. At this time, an operation permission signal is output to the machine in the danger zone, the machine is in operation, and the operator is not permitted to enter the danger zone.

[0032] Next, when the operator presses (pushes) the push button 2, the operation surface 20a of the operation unit 20 of the push button 2 moves to the emergency stop position (dashed line position) as shown in FIG. 2. The push button 2 is temporarily locked in this emergency stop position by a locking mechanism (not shown). At this time, the movable contact 23 moves away from the fixed contact 32 of the circuit C1, and the circuit C1 enters the OFF state. Meanwhile, the circuit C2 remains in the OFF state. At this time, the operation permission signal to the machine in the danger zone is turned OFF, and the machine transitions to the emergency stop state. Furthermore, the through-hole 21a of the shaft 21 of the push button 2 is not aligned in the z direction with the through-holes 30a, 30b of the cylindrical portion 30 of the case 3, and is offset, preventing the operator from entering the danger zone.

[0033] Next, when the operator further depresses (pushes) the push button 2, the operation surface 20a of the operation portion 20 of the push button 2 moves to the padlock insertion position (position indicated by the two-dot chain line) as shown in Figure 3. The push button 2 is temporarily locked at this padlock insertion position by a locking mechanism (not shown). At this time, the center line 21a of the through hole 21a of the shaft portion 21 of the push button 2 c are the center lines 30a of the through holes 30a and 30b of the cylindrical portion 30 of the case 3. c , 30b c, and through-hole 21a is aligned in the z-direction with respect to through-holes 30a, 30b. At this time, movable contact 23 contacts fixed contact 33 of circuit C2, turning circuit C2 on. This detects that through-holes 21a, 30a, 30b are aligned in a straight line (i.e., as described below, a state in which a padlock is inserted or can be inserted, i.e., a state in which a padlock can be inserted). Meanwhile, circuit C1 remains off. At this time, under an emergency stop condition of the machine in the hazardous area, circuit C2 detects that through-holes 21a, 30a, 30b are aligned and ready to insert a padlock, thereby permitting the operator to enter the hazardous area.

[0034] Next, as shown in Figure 4, at the padlock insertable position (Figure 3), the shackle portion 100a of the padlock 100 is inserted into each of the through-holes 21a, 30a, and 30b to lock the lock. At this time, the through-holes 21a, 30a, and 30b are kept aligned in a straight line, so the shackle portion 100a of the padlock 100 can be smoothly inserted into each of the through-holes 21a, 30a, and 30b.

[0035] In addition, when in the padlock insertable position, the push button 2 may not be locked at the padlock insertable position, and for example, the push button 2 may be biased toward the emergency stop position by a biasing means (not shown). In this case, the operator presses the push button 2 from the emergency stop position (FIG. 2), holds the push button 2 by hand at the padlock insertable position (FIG. 3) against the biasing force of the biasing means, and aligns the through holes 21a, 30a, 30b in a straight line, and then inserts the shackle portion 100a of the padlock 100 into each of the through holes 21a, 30a, 30b to lock the door. At this time, the shackle portion 100a of the padlock 100 is inserted into each of the through-holes 21a, 30a, 30b, maintaining the alignment of the through-holes 21a, 30a, 30b, so it can be said that the circuit C2 detects that the shackle portion 100a of the padlock 100 is inserted. In this case, the two conditions that the machine in the hazardous area is in an emergency stop state and the padlock 100 is attached are satisfied, and the operator is permitted to enter the hazardous area.

[0036] Thus, according to the first embodiment, by operating (pushing) the push button 2, the through hole (first insertion hole) 21a for inserting a padlock on the push button 2 side and the through holes (second insertion holes) 30a, 30b for inserting a padlock on the case 3 side are aligned, and the circuit C2 detects that the shackle portion 100a of the padlock 100 is in a state where it can be inserted or that the shackle portion 100a of the padlock 100 has been inserted.

[0037] When circuit C2 detects that the shackle portion 100a of the padlock 100 is inserted into each of the through holes 21a, 30a, 30b, it can detect the insertion of the padlock 100 into each of the through holes 21a, 30a, 30b, making it possible to monitor whether the padlock 100 is attached, thereby preventing forgetting to lock the padlock 100 and improving safety. Also, when circuit C2 detects that the insertion holes 21a, 30a, 30b are aligned and ready for the padlock 100 to be inserted, i.e., that the padlock 100 can be inserted, it can detect that the insertion holes 21a, 30a, 30b are aligned and ready for the padlock to be inserted, making it possible to monitor whether the insertion holes 21a, 30a, 30b are aligned and ready for the padlock to be inserted, thereby reducing the risk of the emergency stop state being inadvertently reset and improving safety.

[0038] [Second Example] Figures 5 to 8 are diagrams illustrating a padlock-compatible emergency stop switch according to a second embodiment of the present invention. Figure 5(a) is a schematic vertical cross-sectional view of the emergency stop switch, and Figure 5(b) is a schematic cross-sectional view taken along line BB. Figures 6 to 8 show the operating procedure of the emergency stop switch in Figure 5 in chronological order. In each figure, the same reference numerals as those in the first embodiment indicate the same or corresponding parts.

[0039] As shown in Figure 5(a), in the padlock-compatible emergency stop switch 1 of this embodiment, the through hole (first insertion hole) 21a for inserting a padlock formed in the shaft portion 21 of the push button 2 is composed of two through holes 21a1 and 21a2 extending in a direction diagonally intersecting the z direction and arranged parallel to each other, as shown in Figure 5(b).

[0040] 5(b), the through holes (second insertion holes) 30a, 30b for inserting padlocks formed in the cylindrical portion 30 of the case 3 are composed of through holes 30a1, 30b1 arranged in a straight line in the z direction and through holes 30a2, 30b2 arranged in a straight line in the z direction, and the through holes 30a1, 30b1 and the through holes 30a2, 30b2 are arranged parallel to each other. As shown in FIG. 5(a), in the initial position before the push button 2 is pressed, each through hole 21a (i.e., 21a1, 21a2) of the shaft portion 21 of the push button 2 is offset, i.e., misaligned, by a predetermined amount in the x direction with respect to each through hole 30a, 30b (i.e., each through hole 30a1, 30b1, 30a2, 30b2) of the cylindrical portion 30 of the case 3.

[0041] The emergency stop switch 1 is provided with a circuit C1 having a fixed contact 32 as shown in Figure 5(a), and also with a circuit C2 having a movable contact 34 that can rotate in conjunction with the rotation of the shaft portion 21 of the push button 2, and a fixed contact 35 with which the movable contact 34 can come into contact as shown in Figure 5(b).

[0042] The operating procedure of the emergency stop switch 1 will be described with reference to FIGS. First, before the push button 2 is operated, i.e., before an emergency stop is initiated, the operating surface 20a of the operating unit 20 of the push button 2 is located in the initial position (solid line position) as shown in FIG. 5(a). At this time, the through-hole 21a (i.e., through-holes 21a1 and 21a2) of the shaft 21 of the push button 2 is not aligned in the z direction with the through-holes 30a and 30b (i.e., through-holes 30a1, 30b1, 30a2, and 30b2) of the cylindrical portion 30 of the case 3, and is offset in the z direction. Furthermore, the movable contact 23 is in contact with the fixed contact 32 of the circuit C1, and the circuit C1 is in the ON state. Meanwhile, the circuit C2 is in the OFF state (see FIG. 5(b)). At this time, an operation permission signal is output to the machinery in the danger zone, and the machinery is in operation, prohibiting the operator from entering the danger zone.

[0043] Next, when the operator presses (pushes) the push button 2, the operation surface 20a of the operation unit 20 of the push button 2 moves to the emergency stop position (position indicated by the dashed line) as shown in FIG. 6(a). The push button 2 is temporarily locked in this emergency stop position by a locking mechanism (not shown). At this time, the movable contact 23 moves away from the fixed contact 32 of the circuit C1, and the circuit C1 enters the OFF state. Meanwhile, the circuit C2 remains in the OFF state (see FIG. 6(b)). At this time, the operation permission signal to the machine in the danger zone is turned OFF, and the machine transitions to the emergency stop state. Furthermore, the center lines of the through holes 21a (i.e., through holes 21a1, 21a2) in the shaft 21 of the push button 2 are positioned at the same x-direction position relative to the through holes 30a, 30b (i.e., through holes 30a1, 30b1, 30a2, 30b2) in the cylindrical portion 30 of the case 3 (see Figure 1(a)), but are not aligned in the z-direction (see Figure 1(b)), remaining offset and preventing the operator from entering the danger zone.

[0044] Next, when the operator rotates (turns) the push button 2, the center line 21a of the through hole 21a of the shaft 21 of the push button 2 becomes equal to the center line 21a of the through hole 21a of the shaft 21 of the push button 2 as shown in FIG. c However, the center lines 30a of the through holes 30a and 30b of the cylindrical portion 30 of the case 3 are c , 30b c 10B, the through-hole 21a is aligned in the z-direction with the through-holes 30a and 30b. More specifically, as shown in FIG. 10B, the through-hole 21a1 of the shaft 21 of the push button 2 is aligned in the z-direction with the through-holes 30a1 and 30b1 of the cylindrical portion 30 of the case 3, and the through-hole 21a2 of the shaft 21 of the push button 2 is aligned in the z-direction with the through-holes 30a2 and 30b2 of the cylindrical portion 30 of the case 3.

[0045] When the push button 2 is rotated, the operating surface 20a of the operating part 20 of the push button 2 is not pressed, so the x-direction position of the operating surface 20a does not change. However, by rotating the push button 2, the through hole 21a on the push button 2 side is aligned with the respective through holes 30a, 30b on the case 3 side, making it possible to insert a padlock. Therefore, in Figure 7(a), for the sake of convenience, the dotted line position is described as the padlock insertion position.

[0046] In this padlock insertion position, rotating the push button 2 rotates the movable contact 34 in conjunction with the shaft 21, bringing it into contact with the fixed contact 35, and the circuit C2 is turned on (see FIG. 7(b)). This detects that the through-holes 21a, 30a, and 30b are aligned in a straight line (more specifically, the through-hole 21a1 is aligned with the through-holes 30a1 and 30b1, and the through-hole 21a2 is aligned with the through-holes 30a2 and 30b2) (i.e., a padlock is being inserted or can be inserted, i.e., a padlock can be inserted). Meanwhile, the circuit C1 remains off. At this time, under an emergency stop condition of the machine in the hazardous area, the circuit C2 detects that the through-holes 21a, 30a, and 30b are aligned and ready for padlock insertion, allowing the operator to enter the hazardous area.

[0047] Next, as shown in Figure 8(a), the shackle portion 100a of the padlock 100 is inserted into each of the through holes 21a, 30a, and 30b to lock the lock. At this time, the insertion of the shackle portion 100a is not limited to the through holes 21a2, 30a2, and 30b2 as shown in Figure 8(b), but may also be the through holes 21a1, 30a1, and 30b1.

[0048] As described above, according to the second embodiment, by operating (turning) the push button 2, the through hole (first insertion hole) 21a for inserting a padlock on the push button 2 side and the through holes (second insertion holes) 30a, 30b for inserting a padlock on the case 3 side are aligned, and the circuit C2 detects that the shackle portion 100a of the padlock 100 is in a state where it can be inserted, that is, a state where it can be inserted or is insertable. This makes it possible to monitor whether the insertion holes 21a, 30a, 30b are aligned, which reduces the risk of the emergency stop state being inadvertently reset and improves safety.

[0049] In this second embodiment, multiple circuits C2 each having a rotatable movable contact 34 and a fixed contact 35 with which the movable contact 34 can come into contact may be provided. Generally, emergency stop switches are designed so that the push button 2 is rotated in one direction to return to its initial position when resetting from the emergency stop state (i.e., restoring the operation permission signal to the machine). Therefore, depending on the rotation position of the push button 2, the push button 2 may be upside down relative to the illustrated state (i.e., the movable contact 34 may be in a diagonal position, i.e., a point-symmetrical position, relative to the illustrated position). In this case, providing multiple circuits C2 allows the insertion of a padlock to be detected even when the push button 2 is upside down.

[0050] [Third Example] Figures 9 to 15 are diagrams illustrating a padlock-compatible emergency stop switch according to a third embodiment of the present invention. Figure 9 is a schematic vertical cross-sectional view of the emergency stop switch, Figures 10 and 11 are diagrams showing the operating procedure of the emergency stop switch in chronological order, Figures 12 to 14 are overall perspective views showing the specific structure of the emergency stop switch of Figures 9 to 11, and Figure 15 is a vertical cross-sectional view taken along line XV-XV of Figure 12. In each figure, the same reference numerals as those in the first and second embodiments indicate the same or corresponding parts.

[0051] 9, 12, 13, and 15, the emergency stop switch 1 according to the third embodiment includes, in addition to a push button 2 and a case 3, a roughly ring-shaped housing portion 5 disposed on the outer periphery of the cylindrical portion 30 of the case 3, and a ring-shaped detection portion (detection portion) 6 (only a part of which is shown in FIG. 9) supported by the housing portion 5 so as to be slidable in the axial direction (x direction). The detection portion 6 can take a retracted position where it is retracted within the housing portion 5, and an extended position where it extends and protrudes from the housing portion 5. A compression spring (not shown) may be disposed within the housing portion 5 so that the detection portion 6 is constantly biased in the protruding direction.

[0052] As shown in FIG. 9, the housing 5 is provided with a circuit (detection means) C2 having a fixed contact 51. An extension 60 extending in the x-direction from the rear surface of the detection unit 6 is connected to the rear surface of the detection unit 6. A movable contact 61 that can come into contact with the fixed contact 51 is attached to the tip of the extension 60. The movable contact 61 moves together with the push button 2 via the extension 60 and the detection unit 6. As shown in FIG. 15, the housing 5 incorporates a microswitch 50. The microswitch 50 has an actuator 50a that the ring-shaped detection unit 6 can come into contact with. When the ring-shaped detection unit 6 moves in the axial direction (x-direction), the ring-shaped detection unit 6 comes into contact with the actuator 50a, applying a pressing force to turn on the internal contacts of the microswitch 50. The movable contact 61 and fixed contact 51 in FIG. 9 correspond to the internal contacts of the microswitch 50 in FIG. 15. In Fig. 9, the contacts are arranged on the upper side of the cylindrical portion 30, but in Fig. 15, the microswitch 50 having the contacts is shown arranged on the lower side of the cylindrical portion 30. As shown in Fig. 9, the cylindrical portion 30 is attached to the panel P via a base portion 5A arranged at the axial end of the housing portion 5. Therefore, the housing portion 5 and the detection portion 6 are provided integrally with the push button 2 and the case 3 via the base portion 5A. Note that Figs. 12 to 15 show a contact portion (contact block portion) C in which the contacts of the emergency stop switch 1 are built.

[0053] The operating procedure of the emergency stop switch 1 will be described with reference to FIGS. First, before the push button 2 is operated, i.e., before an emergency stop is initiated, the operation surface 20a of the operation unit 20 of the push button 2 is located in the initial position (solid line position) as shown in FIG. 9 . At this time, the through-hole 21a of the shaft 21 of the push button 2 is not aligned in the z direction with the through-holes 30a, 30b of the cylindrical portion 30 of the case 3, but is offset. The movable contact 23 is in contact with the fixed contact 32 of the circuit C1, and the circuit C1 is in the ON state. Meanwhile, the circuit C2 is in the OFF state. At this time, the detection unit 6 is located in a shielding position, covering and shielding the through-holes 30a, 30b of the cylindrical portion 30 of the case 3 from the outer periphery (FIG. 9 shows only one of the through-holes 30a shielded). At this time, an operation permission signal is output to the machinery in the danger zone, and the machinery is in operation, prohibiting the operator from entering the danger zone.

[0054] Next, when the operator presses (pushes) the push button 2, the operation surface 20a of the operation unit 20 of the push button 2 moves to the emergency stop position (dashed line position) as shown in FIG. 10. The push button 2 is temporarily locked in this emergency stop position by a locking mechanism (not shown). At this time, the movable contact 23 moves away from the fixed contact 32 of the circuit C1, and the circuit C1 enters the OFF state. Meanwhile, the circuit C2 remains in the OFF state. At this time, the operation permission signal to the machine in the danger zone is turned OFF, and the machine transitions to the emergency stop state. At this time, the through-hole 21a of the shaft 21 of the push button 2 is aligned in the z direction with the through-holes 30a and 30b of the cylindrical portion 30 of the case 3, but the detection unit 6 is still positioned in the shielding position, shielding the through-holes 30a and 30b.

[0055] Next, as shown in FIG. 11, the operator presses the pressing surface 6a on the front side of the detector 6 with the shackle 100a of the padlock 100, moving the detector 6 to the open position where the detector 6 opens the through-hole 30a of the cylindrical portion 30 of the case 3 without blocking it. From this state, the shackle 100a of the padlock 100 is inserted into the through-hole 30a, the through-hole 21a of the shaft 21 of the push button 2, and the through-hole 30b of the cylindrical portion 30 to lock the lock. At this time, the detector 6 is retracted into the housing 5 (see FIG. 14). As a result, the movable contact 61, which moves in conjunction with the detector 6, comes into contact with the fixed contact 51 of the circuit C2, turning the circuit C2 on. This detects that the shackle 100a of the padlock 100 has been inserted into each of the through-holes 21a, 30a, and 30b. In this case, the operator is permitted to enter the danger zone if two conditions are met: the machine in the danger zone is in an emergency stop state, and the padlock 100 is installed.

[0056] According to the third embodiment, when the push button 2 is operated (pushed), the through-hole (first insertion hole) 21a for inserting a padlock on the push button 2 side is aligned with the through-holes (second insertion holes) 30a, 30b for inserting a padlock on the case 3 side, and it is possible to detect that the shackle portion 100a of the padlock 100 has been inserted into each of the through-holes 21a, 30a, 30b. This makes it possible to monitor whether the padlock 100 is attached, thereby preventing forgetting to lock the padlock 100 and improving safety. Note that in this third embodiment, the ring-shaped detector 6 may be divided circumferentially into multiple detectors 6, and each of the multiple detectors 6 may be provided with a microswitch 50 (FIG. 15) to accommodate multiple padlocks.

[0057] [Fourth Example] Figures 16 to 20 are diagrams for explaining a padlock-compatible emergency stop switch according to a fourth embodiment of the present invention. Figure 16 is a schematic vertical cross-sectional view of the emergency stop switch, and Figures 17 to 20 are diagrams showing the operation procedure of the emergency stop switch in chronological order. In each figure, the same reference numerals as those in the first to third embodiments indicate the same or corresponding parts.

[0058] In the third embodiment, the ring-shaped detector 6 is supported by the housing 5 so as to slide axially (in the x direction). However, in the emergency stop switch 1 according to the fourth embodiment, the ring-shaped detector 6 has a stay 6A extending in the z direction. The upper end of the stay 6A is rotatably attached to the housing 5 via a hinge 6p. This allows the detector 6 to be supported by the housing 5 so as to be able to swing freely. The detector 6 can be positioned in a retracted position retracted within the housing 5 and in an extended position protruding from the housing 5. A compression spring (not shown) may be provided in the housing 5 so that the detector 6 is constantly biased toward the protruding side. The front side of the detector 6 is formed with a pressing surface 6a and an inclined surface 6b, which is located above (i.e., radially inward of) the pressing surface 6a and extends at an angle relative to the pressing surface 6a.

[0059] The operating procedure of the emergency stop switch 1 will be described with reference to FIGS. First, before the push button 2 is operated, i.e., before an emergency stop is performed, the operation surface 20a of the operation unit 20 of the push button 2 is located in the initial position (solid line position) as shown in FIG. 16. At this time, the through-hole 21a of the shaft 21 of the push button 2 is not aligned in the z direction with the through-holes 30a, 30b of the cylindrical portion 30 of the case 3, but is offset. Also, the movable contact 23 is in contact with the fixed contact 32 of the circuit C1, and the circuit C1 is in the ON state. Meanwhile, the circuit C2 is in the OFF state. At this time, the detection unit 6 is located in a shielding position, covering the outer periphery of the through-hole 30b of the cylindrical portion 30 of the case 3. Also, at this time, an operation permission signal is output to the machine in the danger zone, and the machine is in operation, prohibiting the operator from entering the danger zone.

[0060] Next, when the operator presses (pushes) the push button 2, the operation surface 20a of the operation unit 20 of the push button 2 moves to the emergency stop position (dashed line position) as shown in FIG. 17. The push button 2 is temporarily locked in this emergency stop position by a locking mechanism (not shown). At this time, the movable contact 23 moves away from the fixed contact 32 of the circuit C1, and the circuit C1 enters the OFF state. Meanwhile, the circuit C2 remains in the OFF state. At this time, the operation permission signal to the machine in the danger zone is turned OFF, and the machine transitions to the emergency stop state. At this time, the through-hole 21a of the shaft 21 of the push button 2 is aligned in the z direction with the through-holes 30a and 30b of the cylindrical portion 30 of the case 3, but the detection unit 6 is still positioned in the shielding position, shielding the through-hole 30b.

[0061] Next, as shown in FIG. 18, the operator inserts the shackle portion 100a of the padlock 100 into the through-hole 30a of the cylindrical portion 30 of the case 3. At this time, the tip of the shackle portion 100a passes through the through-hole 30b of the cylindrical portion 30 of the case 3 and abuts against the inclined surface 6b on the front side of the detection unit 6, exerting a pressing force on the inclined surface 6b. Then, the detection unit 6 swings around the hinge 6p via the stay 6A, and as shown in FIG. 19, the detection unit 6 is retracted into the housing unit 5 and moved to the retracted position. At this time, the shackle portion 100a abuts against the pressing surface 6a of the detection unit 6. From this state, the padlock 100 is locked as shown in FIG. 20.

[0062] 19, the movable contact 61, which moves in conjunction with the detector 6, comes into contact with the fixed contact 51 of the circuit C2, turning the circuit C2 on. This detects that the shackle 100a of the padlock 100 has been inserted into each of the through-holes 21a, 30a, and 30b. In this case, the two conditions that the machine in the hazardous area is in an emergency stop state and that the padlock 100 is attached are met, and the operator is permitted to enter the hazardous area.

[0063] Thus, according to the fourth embodiment, when the push button 2 is operated (pushed), the through-hole (first insertion hole) 21a for inserting the padlock on the push button 2 side and the through-holes (second insertion holes) 30a, 30b for inserting the padlock on the case 3 side are aligned, and it is possible to detect that the shackle portion 100a of the padlock 100 has been inserted into each of the through-holes 21a, 30a, 30b, so it becomes possible to monitor whether the padlock 100 is attached or not, thereby preventing forgetting to lock the padlock 100 and improving safety. Furthermore, in this fourth embodiment, the ring-shaped detection portion 6 is supported so as to be able to swing freely, so that the ring-shaped detection portion 6 can be reliably pressed even when the padlock is tilted.

[0064] Fifth Example 21 is a diagram for explaining a padlock-compatible emergency stop switch according to a fifth embodiment of the present invention, showing a schematic vertical cross-sectional configuration of the emergency stop switch. In the figure, the same reference numerals as those in the third embodiment indicate the same or corresponding parts.

[0065] In the third embodiment, the cylindrical portion 30 of the case 3 is attached to the panel P via the base portion 5A of the housing portion 5 (see Figure 9), thereby showing an example in which the housing portion 5 and the detection portion 6 are integrally formed with the push button 2 and the case 3. However, in this fifth embodiment, as shown in Figure 21, the housing portion 5 does not have a base portion extending toward the cylindrical portion 30 of the case 3, and the housing portion 5 and the detection portion 6 are not integrally formed with the push button 2 and the case 3, i.e., they are formed as separate components.

[0066] The effects of the fifth embodiment are the same as those of the third embodiment, and when the push button 2 is operated (pushed), the through-hole (first insertion hole) 21a for inserting a padlock on the push button 2 side is aligned with the through-holes (second insertion holes) 30a, 30b for inserting a padlock on the case 3 side, and it is possible to detect that the shackle portion 100a of the padlock 100 has been inserted into each of the through-holes 21a, 30a, 30b. This makes it possible to monitor whether the padlock 100 is attached, thereby preventing forgetting to lock the padlock 100 and improving safety. In addition, the housing portion 5 can be retrofitted near an already installed emergency stop switch, which makes it possible to detect the insertion of a padlock without modifying the installed emergency stop switch.

[0067] [Sixth Example] Figures 22 to 24 are diagrams for explaining a padlock-compatible emergency stop switch according to a sixth embodiment of the present invention. Figure 22 is a schematic vertical cross-sectional view of the emergency stop switch, and Figures 23 and 24 are diagrams showing the operating procedure of the emergency stop switch in chronological order. In each figure, the same reference numerals as those in the first to fifth embodiments indicate the same or corresponding parts.

[0068] In the emergency stop switch 1 according to the sixth embodiment, the circuit C2 has a proximity sensor 24 provided inside the shaft 21 of the push button 2. The proximity sensor 24 is for detecting that a metal shackle of a padlock has been inserted into the through-hole 21a of the shaft 21, and is configured, for example, as an inductive proximity sensor or a capacitive proximity sensor. Note that a transmissive or reflective photoelectric sensor may be used instead of the proximity sensor 24. The proximity sensor 24 is shown in simplified form in Figures 22 to 24.

[0069] The operating procedure of the emergency stop switch 1 will be described with reference to FIGS. First, before the push button 2 is operated, i.e., before an emergency stop is performed, the operating surface 20a of the operating portion 20 of the push button 2 is located in the initial position (position indicated by the solid line) as shown in Fig. 22. At this time, the through-hole 21a of the shaft portion 21 of the push button 2 is not aligned in the z direction with the through-holes 30a, 30b of the cylindrical portion 30 of the case 3, but is offset. Also, the movable contact 23 is in contact with the fixed contact 32 of the circuit C1, and the circuit C1 is in the ON state. Meanwhile, the circuit C2 is in the OFF state. At this time, an operation permission signal is output to the machine in the danger zone, the machine is in operation, and the operator is not permitted to enter the danger zone.

[0070] Next, when the operator presses (pushes) the push button 2, the operation surface 20a of the operation unit 20 of the push button 2 moves to the emergency stop position (dashed line position) as shown in FIG. 23. The push button 2 is temporarily locked in this emergency stop position by a locking mechanism (not shown). At this time, the movable contact 23 moves away from the fixed contact 32 of the circuit C1, and the circuit C1 enters the OFF state. Meanwhile, the circuit C2 remains in the OFF state. At this time, the operation permission signal to the machine in the danger zone is turned OFF, and the machine transitions to the emergency stop state. At this time, the through-hole 21a of the shaft 21 of the push button 2 is aligned in the z direction with the through-holes 30a and 30b of the cylindrical portion 30 of the case 3.

[0071] Next, the operator inserts the shackle portion 100a of the padlock 100 into each of the through-holes 21a, 30a, and 30b to lock the door, as shown in Figure 24. At this time, the proximity sensor 24 detects the shackle portion 100a of the padlock 100 and turns on, turning on the circuit C2. This satisfies two conditions: the machine in the hazardous area is in an emergency stop state, and the padlock 100 is attached. This allows the operator to enter the hazardous area.

[0072] Thus, according to the sixth embodiment, by operating (pushing) the push button 2, the through hole (first insertion hole) 21a for inserting the padlock on the push button 2 side and the through holes (second insertion holes) 30a, 30b for inserting the padlock on the case 3 side are aligned, and it is possible to detect that the shackle portion 100a of the padlock 100 has been inserted into each of the through holes 21a, 30a, 30b. This makes it possible to monitor whether the padlock 100 is attached, thereby preventing forgetting to lock the padlock 100 and improving safety.

[0073] [Seventh Example] Figures 25 to 27 are diagrams for explaining a padlock-compatible emergency stop switch according to a seventh embodiment of the present invention. Figure 25 is a schematic vertical cross-sectional view of the emergency stop switch, and Figures 26 and 27 are diagrams showing the operating procedure of the emergency stop switch in chronological order. In each figure, the same reference numerals as those in the first to sixth embodiments indicate the same or corresponding parts.

[0074] The emergency stop switch 1 according to the seventh embodiment differs from the sixth embodiment in that a microswitch 25 is provided instead of the proximity sensor 24 of the sixth embodiment. The microswitch 25 has a contact 25a in a recess 21b that communicates with the through-hole 21a of the shaft 21 of the push button 2, and the contact 25a is provided so as to be able to appear and disappear from the through-hole 21a. The microswitch 25 is connected to the contact 25a.

[0075] The operating procedure of the emergency stop switch 1 will be described with reference to FIGS. First, before the push button 2 is operated, i.e., before an emergency stop is performed, the operation surface 20a of the operation unit 20 of the push button 2 is located in the initial position (solid line position) as shown in Figure 25. At this time, the through-hole 21a of the shaft 21 of the push button 2 is not aligned in the z direction with the through-holes 30a, 30b of the cylindrical portion 30 of the case 3, but is offset. The movable contact 23 is in contact with the fixed contact 32 of the circuit C1, and the circuit C1 is in the ON state. Meanwhile, the contactor 25a protrudes into the through-hole 21a of the shaft 21 of the push button 2, the microswitch 25 is in the OFF state, and the circuit C2 is in the OFF state. At this time, an operation permission signal is output to the machinery in the hazardous area, the machinery is in operation, and the operator is not permitted to enter the hazardous area.

[0076] Next, when the operator presses (pushes) the push button 2, the operation surface 20a of the operation unit 20 of the push button 2 moves to the emergency stop position (dashed line position) as shown in FIG. 26. The push button 2 is temporarily locked in this emergency stop position by a locking mechanism (not shown). At this time, the movable contact 23 moves away from the fixed contact 32 of the circuit C1, and the circuit C1 enters the OFF state. Meanwhile, the circuit C2 remains in the OFF state. At this time, the operation permission signal to the machine in the danger zone is turned OFF, and the machine transitions to the emergency stop state. At this time, the through-hole 21a of the shaft 21 of the push button 2 is aligned in the z direction with the through-holes 30a and 30b of the cylindrical portion 30 of the case 3.

[0077] Next, as shown in Figure 27, the operator inserts the shackle portion 100a of the padlock 100 into each of the through-holes 21a, 30a, and 30b to lock the device. When the shackle portion 100a is inserted into the through-hole 21a, the shackle portion 100a causes the contact 25a of the microswitch 25 to sink into the recess 25b. This turns on the switch 25, turning on the circuit C2. This satisfies two conditions: the machine in the hazardous area is in an emergency stop state, and the padlock 100 is installed. This allows the operator to enter the hazardous area.

[0078] Thus, according to the seventh embodiment, by operating (pushing) the push button 2, the through hole (first insertion hole) 21a for inserting the padlock on the push button 2 side and the through holes (second insertion holes) 30a, 30b for inserting the padlock on the case 3 side are aligned, and it is possible to detect that the shackle portion 100a of the padlock 100 has been inserted into each of the through holes 21a, 30a, 30b. This makes it possible to monitor whether the padlock 100 is attached, thereby preventing forgetting to lock the padlock 100 and improving safety.

[0079] [Eighth Example] Figures 28 to 30 are diagrams for explaining a padlock-compatible emergency stop switch according to an eighth embodiment of the present invention. Figure 28 is a schematic vertical cross-sectional view of the emergency stop switch, and Figures 29 and 30 are diagrams showing the operating procedure of the emergency stop switch in chronological order. In each figure, the same reference numerals as those in the first to seventh embodiments indicate the same or corresponding parts.

[0080] In the emergency stop switch 1 according to the eighth embodiment, the circuit C2 includes a proximity sensor 52 provided inside the housing 5. The proximity sensor 52 detects the padlock body (i.e., the key mechanism) when the shackle of the padlock is inserted into each of the through-holes 21a, 30a, and 30b, and is configured, for example, as an inductive proximity sensor or a capacitive proximity sensor. In FIGS. 28 to 30, the proximity sensor 52 is shown in a simplified form. Instead of the proximity sensor 52, a transmissive or reflective photoelectric sensor may be used, or a combination of an RFID (Radio Frequency Identification) tag and an antenna for detecting the tag may be used. Furthermore, the proximity sensor 52 may detect both the key mechanism and the shackle, or may detect only the shackle. For example, the proximity sensor 52 may be built into the push button 2 to detect the insertion of the shackle into each of the through-holes 21a, 30a, and 30b. In this eighth embodiment, the cylindrical portion 30 of the case 3 is attached to the panel P via the base portion 5A of the housing portion 5, so that the housing portion 5 and the proximity sensor 52 are integrally formed with the push button 2 and the case 3.

[0081] The operating procedure of the emergency stop switch 1 will be described with reference to FIGS. First, before the push button 2 is operated, i.e., before an emergency stop is performed, the operating surface 20a of the operating portion 20 of the push button 2 is located in the initial position (position indicated by the solid line) as shown in Figure 28. At this time, the through-hole 21a of the shaft portion 21 of the push button 2 is not aligned in the z direction with the through-holes 30a, 30b of the cylindrical portion 30 of the case 3, but is offset. Also, the movable contact 23 is in contact with the fixed contact 32 of the circuit C1, and the circuit C1 is in the ON state. Meanwhile, the circuit C2 is in the OFF state. At this time, an operation permission signal is output to the machine in the danger zone, the machine is in operation, and the operator is not permitted to enter the danger zone.

[0082] Next, when the operator presses (pushes) the push button 2, the operation surface 20a of the operation unit 20 of the push button 2 moves to the emergency stop position (dashed line position) as shown in FIG. 29. The push button 2 is temporarily locked in this emergency stop position by a locking mechanism (not shown). At this time, the movable contact 23 moves away from the fixed contact 32 of the circuit C1, and the circuit C1 enters the OFF state. Meanwhile, the circuit C2 remains in the OFF state. At this time, the operation permission signal to the machine in the danger zone is turned OFF, and the machine transitions to the emergency stop state. At this time, the through-hole 21a of the shaft 21 of the push button 2 is aligned in the z direction with the through-holes 30a and 30b of the cylindrical portion 30 of the case 3.

[0083] Next, the operator inserts the shackle portion 100a of the padlock 100 into each of the through-holes 21a, 30a, and 30b to lock the device, as shown in Figure 30. At this time, the proximity sensor 52 detects the main body 100A of the padlock 100 and turns on, turning on the circuit C2. This satisfies two conditions: the machine in the danger zone is in an emergency stop state, and the padlock 100 is installed. This allows the operator to enter the danger zone.

[0084] Thus, according to the eighth embodiment, by operating (pushing) the push button 2, the through hole (first insertion hole) 21a for inserting a padlock on the push button 2 side and the through holes (second insertion holes) 30a, 30b for inserting a padlock on the case 3 side are aligned, and the shackle portion 100a of the padlock 100 is inserted into each of the through holes 21a, 30a, 30b, and it can be detected that the padlock 100 has been attached.Therefore, it becomes possible to monitor whether the padlock 100 is attached, which prevents forgetting to lock the padlock 100 and improves safety.

[0085] [Ninth Example] 31 is a diagram for explaining a padlock-compatible emergency stop switch according to a ninth embodiment of the present invention, showing a schematic vertical cross-sectional configuration of the emergency stop switch. In the figure, the same reference numerals as those in the eighth embodiment indicate the same or corresponding parts.

[0086] In the eighth embodiment, the cylindrical portion 30 of the case 3 is attached to the panel P via the base portion 5A of the housing portion 5 (see Figure 28), thereby showing an example in which the housing portion 5 and the proximity sensor 52 are integrally formed with the push button 2 and the case 3. However, in this ninth embodiment, as shown in Figure 31, the housing portion 5 does not have a base portion extending toward the cylindrical portion 30 of the case 3, and the housing portion 5 and the proximity sensor 52 are not integrally formed with the push button 2 and the case 3, i.e., they are formed as separate components.

[0087] The ninth embodiment has the same effects as the eighth embodiment, in that when the push button 2 is operated (pushed) to align the through-hole (first insertion hole) 21a for inserting a padlock on the push button 2 side with the through-holes (second insertion holes) 30a, 30b for inserting a padlock on the case 3 side, the main body 100A of the padlock 100 can be detected when the shackle portion 100a of the padlock 100 is inserted into each of the through-holes 21a, 30a, 30b, so that it is possible to monitor whether the padlock 100 is attached or not, thereby preventing forgetting to lock the padlock 100 and improving safety. Furthermore, the housing portion 5 can be retrofitted near an already installed emergency stop switch, which makes it possible to detect the insertion of a padlock without modifying the installed emergency stop switch.

[0088] [Tenth Example] 32 and 33 are diagrams for explaining a padlock-compatible emergency stop switch according to a tenth embodiment of the present invention. Fig. 32 is a schematic vertical cross-sectional view of the emergency stop switch, and Fig. 33 is a diagram showing the operating procedure for the emergency stop switch. In each diagram, the same reference numerals as those in the first to ninth embodiments indicate the same or corresponding parts.

[0089] 32, the emergency stop switch 1 according to the tenth embodiment has a detection unit 6' supported on the housing unit 5 so as to be slidable in the x direction. A movable contact 61 is attached to the back side of the detection unit 6', and the movable contact 61 is arranged to be able to abut against a fixed contact 51 of the circuit C2. The cylindrical portion 30 of the case 3 is attached to the panel P via the base portion 5A of the housing unit 5, and the housing unit 5 and the detection unit 6' are provided integrally with the push button 2 and the case 3.

[0090] The emergency stop switch 1 has a cover 7 for covering the push button 2. The cover 7 is supported on a cover body 8 via a hinge portion 70 so as to be able to open and close. Note that the hinge portion 70 does not necessarily have to be provided, and the cover 7 may be provided detachably on the cover body 8. The cover 7 is provided with a bracket portion 7A having a through hole (third insertion hole) 7a for inserting a padlock. Meanwhile, the cover body 8 is provided with a bracket portion 8A having a through hole (fourth insertion hole) 8a for inserting a padlock. Each of the through holes 7a, 8a extends in the y direction. At least a portion of the through hole 8a is covered and shielded by the detection unit 6'.

[0091] The operating procedure of the emergency stop switch 1 will be described with reference to FIGS. First, before the push button 2 is operated, i.e., before an emergency stop is performed, the operating surface 20a of the operating unit 20 of the push button 2 is located in the initial position (solid line position) as shown in Figure 32. At this time, the movable contact 23 is in contact with the fixed contact 32 of the circuit C1, and the circuit C1 is in the ON state. On the other hand, the circuit C2 is in the OFF state. The detection unit 6' is located in a shielding position where it covers at least a portion of the through-hole 8a of the bracket part 8A. Also, at this time, an operation permission signal is output to the machine in the danger zone, the machine is in operation, and the operator is not permitted to enter the danger zone.

[0092] Next, when the operator presses (pushes) the push button 2, the operation surface 20a of the operation unit 20 of the push button 2 moves to the emergency stop position (dashed line position) as shown in Figure 33 (at this point, the cover 7 is not yet closed). The push button 2 is temporarily locked in this emergency stop position by a locking mechanism (not shown). At this time, the movable contact 23 moves away from the fixed contact 32 of the circuit C1, and the circuit C1 goes into the OFF state. As a result, the operation permission signal to the machine in the hazardous area is turned OFF, and the machine moves into the emergency stop state.

[0093] When the operator closes the cover 7 from this state, the bracket portion 7A of the cover 7 presses the pressing surface 6'a on the front side of the detector 6' during the closing operation of the cover 7. As shown in FIG. 33, the detector 6' is retracted into the housing portion 5, moving it to the open position where the through-hole 8a is opened, aligning the through-hole 7a of the cover 7 with the through-hole 8a of the cover body 8. At this time, the movable contact 61 contacts the fixed contact 51, turning on the circuit C2. This aligns the insertion holes 7a, 8a, indicating that a padlock is inserted or can be inserted, i.e., the padlock is insertable. From this state, the shackle portion 100a of the padlock 100 is inserted into the through-holes 7a, 8a to lock the lock.

[0094] In this case, the operator is permitted to enter the danger zone if two conditions are met: the machine in the danger zone is in an emergency stop state, and the padlock 100 is ready to be inserted.

[0095] Thus, according to the tenth embodiment, by closing the cover 7, the through hole (third insertion hole) 7a for inserting a padlock on the cover 7 side and the through hole (fourth insertion hole) 8a for inserting a padlock on the cover body 8 side are aligned, and it can be detected that the shackle portion 100a of the padlock 100 is in a state where it can be inserted. Therefore, it becomes possible to monitor whether or not the insertion holes 7a, 8a are aligned, which reduces the risk of the emergency stop state being inadvertently reset and improves safety.

[0096] [Eleventh Example] 34 is a diagram for explaining a padlock-compatible emergency stop switch according to an eleventh embodiment of the present invention, showing an emergency stop switch with a cover similar to that of the tenth embodiment. In the figure, the same reference numerals as those of the first to tenth embodiments indicate the same or corresponding parts.

[0097] In the tenth embodiment, an example was shown in which the push button 2 was maintained in the emergency stop position when the cover 7 was closed, but in the emergency stop switch 1 of this eleventh embodiment, when the cover 7 is closed from a state in which the push button 2 is positioned in the emergency stop position (dashed line position), the cover 7 presses the operating surface 20a of the operating part 20 of the push button 2, moving the operating surface 20a to a position where a padlock can be inserted (dashed line position), and as a result, the through hole 7a of the cover 7 is aligned with the through hole 8a of the cover body 8.

[0098] At this time, the movable contact 23 comes into contact with the fixed contact 33 of circuit C2, turning circuit C2 ON. This detects that the through-holes 7a, 8a are aligned and ready for insertion of a padlock, i.e., a padlock is insertable. Meanwhile, circuit C1 is OFF. At this time, under an emergency stop condition of the machine in the hazardous area, circuit C2 detects that the through-holes 7a, 8a are aligned and ready for insertion of a padlock, allowing entry into the hazardous area. Once the through-holes 7a, 8a are aligned, the shackle portion 100a of the padlock 100 is inserted into each of the through-holes 7a, 8a, and locking is performed.

[0099] [Safety Control System] FIG. 35 shows an example of a safety control system including the above-described padlock-compatible emergency stop switch 1. As shown in the figure, the safety control system 200 includes a controller 201. An emergency stop signal from circuit C1 of the emergency stop switch 1 and a detection signal from circuit C2 of the emergency stop switch 1 are input to the input side of the controller 201. An AND circuit is provided inside the controller 201, and only when both the emergency stop signal and the detection signal are input does the output side of the controller 201 output a signal permitting entry into the dangerous area. This entry permit signal unlocks, for example, an interlock (safety switch) at an entrance / exit, allowing an operator to enter the dangerous area. In this way, this safety control system makes it possible to monitor whether the padlock insertion through-holes are aligned or whether a padlock 100 is attached to the emergency stop switch 1.

[0100] [Other Modifications] The above-described embodiments should be considered in all respects as merely illustrative of the present invention, and not limiting. Those skilled in the art will be able to devise various modifications and other embodiments incorporating the principles of the present invention without departing from the spirit and essential characteristics of the present invention, even if not explicitly described herein, in light of the above teachings. For example, while the above-described embodiments illustrate examples in which circuit C2 is configured with normally open contacts, it may instead be configured with normally closed contacts. Furthermore, the microswitch may be any other switch as long as it has a contact for detection.

[0101] [Other application examples] In the above-mentioned embodiments and each of the above-mentioned modified examples, the field of manufacturing (i.e., factory automation (FA)) has been used as an example to explain the field to which the present invention is applicable, but the application of the present invention is not limited to this, and the present invention can also be applied to the fields of construction, civil engineering, catering, and food industries, as well as medical care and distribution. [Industrial Applicability]

[0102] The present invention is useful for a padlock-compatible emergency stop switch and a safety control system equipped with the same. [Explanation of symbols]

[0103] 1: Padlockable emergency stop switch 2: Push button 21a: Through hole (first insertion hole) 3: Case (Housing) 30a, 30b: through holes (second insertion holes) 6: Ring-shaped detector (detector) 6': Detection section 7: Cover 7a: Through hole (third insertion hole) 8: Cover body 8a: Through hole (fourth insertion hole) 100: Padlock 100a: Shackle part 200: Safety Control Systems C2: Circuit (detection means) [Prior art documents] [Patent documents]

[0104] [Patent Document 1] Japanese Patent Application Laid-Open No. 2001-35302 (see FIG. 1) [Patent Document 2] Japanese Patent Application Laid-Open No. 2006-49176 (see paragraphs

[0025] to

[0027] ,

[0033] to

[0035] ,

[0039] ,

[0040] and Figures 2, 7, 8, 11, and 12)

Claims

1. In padlock compatible emergency stop switches, having at least two insertion holes for inserting padlocks; The detection means detects whether the insertion holes are aligned and the padlocks are ready to be inserted or have been inserted. A padlock compatible emergency stop switch.

2. In padlock compatible emergency stop switches, a push button having a first insertion hole for inserting a padlock; a housing that slidably supports the push button and has a second insertion hole for inserting a padlock; a detection means for detecting whether the first and second insertion holes are aligned by operating the push button and a padlock is ready to be inserted or has been inserted; Padlockable emergency stop switch with

3. In padlock compatible emergency stop switches, A push button and a cover that has a third insertion hole for inserting a padlock and that can be opened and closed to cover the push button; a cover body having a fourth insertion hole for inserting a padlock and supporting the cover in an openable / closable or detachable manner; a detection means for detecting whether the third and fourth insertion holes are aligned and ready to insert a padlock by operating the push button or closing the cover; Padlockable emergency stop switch with

4. In claim 1 or 2, The detection means has a detection part that can take a blocking position that blocks the insertion hole and an open position that opens the insertion hole, and when the shackle part of the padlock is inserted into the insertion hole, the shackle part presses the detection part to move the insertion hole to the open position, thereby detecting that the padlock has been inserted. A padlock compatible emergency stop switch.

5. In claim 3, The detection means has a detection unit that can take a blocking position for blocking the insertion hole and an opening position for opening the insertion hole, and when the cover is closed, the cover presses the detection unit to move the insertion hole to the opening position, thereby detecting that the insertion hole is aligned. A padlock compatible emergency stop switch.

6. In claim 1 or 2, The detection means is adapted to detect the shackle or body of the padlock when the padlock is inserted. A padlock compatible emergency stop switch.

7. In claim 2 or 3, After the switch is turned off by operating the push button, the padlock is shifted to an inserted state by further operating the push button. A padlock compatible emergency stop switch.

8. In claim 2 or 3, The operation of the push button is a push operation of pressing the push button or a turn operation of rotating the push button. A padlock compatible emergency stop switch.

9. A padlock-compatible emergency stop switch according to any one of claims 1 to 8 is provided, After an emergency stop is performed by the emergency stop switch, entry into the danger zone in which the machine to be stopped is installed is permitted based on the detection by the detection means. A safety control system characterized by:

Images