Multiple-locking device for lockout system

Abstract

To provide a multiple-locking device in which the tip of a shackle can be pushed down to a closed position together with a slide plate only at the position where the tip of the shackle faces an insertion hole.SOLUTION: A slide plate 3 of a multiple-locking device 1 includes a flat plate portion 31 having a through hole 31a and a swivel tube portion 32 through which a base end 41 side of a shackle 4 is inserted. The swivel tube portion 32 has a notch 32a in the middle, and the shackle 4 is prevented from coming off by a retaining member 5 fixed to the outer periphery of the notch 32a. A downward stop protrusion 51 of the retaining member 5 protrudes from the notch 32a. On the inside of the case 2, there are formed lowering stopper steps 23c, 24c which allow the shackle 4 and the slide plate 3 to descend without coming into contact with the lowering stopper protrusion 51 when a tip 42 of the shackle 4 is in an axial rotation position facing an insertion hole 21b of the case 2, and which come into contact with the underside of the lowering stopper protrusion 51 at other rotation angle positions to prevent the shackle and the slide plate from descending.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a multiple locking device used in a lockout system that prevents the operation of a switch to start industrial equipment unless all workers remove the padlocks they have set when the equipment is shut down and maintenance and inspection work is performed by multiple workers. [Background technology]

[0002] Conventionally, an interlock device described in Patent Document 1, for example, has been known as a multiple locking device as described above. This device includes a case with multiple through holes; a slide plate with multiple through holes formed at positions corresponding to the through holes in the case, housed in the case so as to move up and down between a closed position where it is pressed down relative to the case and an open position where it is raised up; and a shackle whose base end is inserted into the case and axially fixed so as to be rotatable about its axis relative to the slide plate, and whose tip end is inserted and removed vertically through the insertion hole in the case. The shackle is hooked to a switch operating unit of the device when it is raised up together with the slide plate relative to the main body in the open position, and then pushed down together with the slide plate to the closed position. When the shackle is in the closed position where it is pressed down together with the slide plate relative to the case, the other end of the shackle is inserted into the insertion hole, and all of the through holes in the case and the slide plate are aligned. Multiple workers can individually attach padlocks to the aligned through holes. The shackle cannot be raised to the open position, and therefore the device switch cannot be operated, unless all workers remove their respective padlocks. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-41591 Summary of the Invention [Problem to be solved by the invention]

[0004] In the above-mentioned conventional multiple locking device, the shackle can move up and down together with the slide plate relative to the case even when the tip of the shackle is not facing the insertion hole. Therefore, after the shackle is hooked to the switch operating part, it can be pushed down together with the slide plate to the closed position without inserting the tip into the case. In this state, the through hole of the case and the through hole of the slide plate are aligned, so it is possible to hook the padlock into the through hole, which may cause an incorrect operation. Therefore, an object of the present invention is to provide a multiple locking device that allows the shackle to be pushed down to the closed position together with the slide plate relative to the case only when the tip of the shackle is facing the insertion hole, thereby making it impossible for the padlock to be latched in the closed position. [Means for solving the problem]

[0005] In the following description, reference will be made to the reference numerals in the accompanying drawings, but the present invention is not limited thereto. In order to solve the above problems, in the multiple locking device 1 for a lockout system of the present invention, the slide plate 3 comprises a flat plate portion 31 having a through hole 31a and a swivel tube portion 32 into which the base end 41 of the shackle 4 is inserted. The swivel tube portion 32 has a notch 32a in the middle. The shackle 4 is prevented from coming off in the axial direction by a retaining member 5 fixed to the outer periphery of the notch 32a of the swivel tube portion 32. The retaining member 5 has a downward stop projection 51 that projects from the notch 32a of the swivel tube portion 32. On the inside of the case 2, there are formed lowering stopper steps 23c, 24c which allow the shackle 4 and the slide plate 3 to descend without coming into contact with the lowering stopper protrusion 51 when the tip 42 of the shackle 4 is in an axial rotation position facing the insertion hole 21b of the case 2, and which come into contact with the underside of the lowering stopper protrusion 51 at other rotation angle positions to prevent the shackle and the slide plate from descending. [Effects of the Invention]

[0006] According to the present invention, a multiple locking device can be provided in which the shackle can be pushed down to the closed position together with the slide plate relative to the case only when the tip of the shackle is facing the insertion hole, and therefore the padlock cannot be latched in a position where the tip of the shackle is not facing the insertion hole. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 2 is a perspective view of the multiple locking device of the present invention in a closed state. [Figure 2] 2 is a front view of the multiple locking device of FIG. 1 in a closed state. FIG. [Figure 3] 2 is a side view of the multiple locking device of FIG. 1 in a closed state. FIG. [Figure 4] 2 is an exploded perspective view of the multiple locking device of FIG. 1 from the front side. FIG. [Figure 5] 2 is an exploded perspective view of the multiple locking device of FIG. 1 as seen from the rear side. FIG. [Figure 6] FIG. 6 is an enlarged cross-sectional view taken along the line VI-VI in FIG. [Figure 7] FIG. 7 is an enlarged cross-sectional view taken along line VII-VII in FIG. [Figure 8] 2 is a front view of the multiple locking device of FIG. 1 in an open state. FIG. [Figure 9] FIG. 9 is an enlarged cross-sectional view taken along line IX-IX in FIG. 8. [Figure 10] 2 is a front view of the multiple locking device of FIG. 1 in an open state with the shackle rotated 180°. FIG. [Figure 11] 11 is an enlarged cross-sectional view taken along the line XI-XI in FIG. [Figure 12] 2 is a rear view of the multi-locking device in the open state of FIG. 1 with the cover removed. DETAILED DESCRIPTION OF THE INVENTION

[0008] An embodiment of the present invention will be described with reference to the drawings. The multiple locking device 1 comprises a case 2, a slide plate 3 housed therein, and a shackle 4.

[0009] The case 2 has an upper plate portion 21 having a swivel hole 21a and an insertion hole 21b, an opposing lower plate portion 22, a front plate portion 23, an opposing rear plate portion 24, and left and right side plate portions 25, 26, and has a plurality of through holes 23a, 24a formed through the front plate portion 23 and the rear plate portion 24 in the front-to-rear direction.

[0010] The case 2 is composed of a case body 27 and a case lid 28, both of which are integrally molded from synthetic resin and snap-engaged together in the front-to-rear direction to form a flat box-like body.

[0011] The case body 27 includes an upper plate portion 21, a lower plate portion 22, a front plate portion 23, and standing pieces 25a, 26a on the left and right side edges of the front plate portion.

[0012] The case cover 28 has a rear plate 24 and standing pieces 25b, 26b on the left and right side edges of the rear plate 24. The standing pieces 25b, 26b are joined to the standing pieces 25a, 26a of the case body 27 to form the left and right side plate parts 25, 26.

[0013] The slide plate 3 has a flat plate portion 31 and a swivel cylinder portion 32, and is housed in the case 2 together with the shackle 4 so as to move up and down between a closed position where it is pressed down relative to the case 2 and an open position where it is pulled up. The flat plate portion 31 has a plurality of through holes 31a at positions corresponding to the through holes 23a, 24a of the case 2. The swivel cylinder portion 32 has a notch 32a in the middle, through which the base end portion 41 of the shackle 4 is inserted.

[0014] The base end 41 side of the shackle 4 is inserted into the swivel tube portion 32 via the swivel hole 21a so as to be rotatable about the axis, and is prevented from coming off in the axial direction by a retaining member 5 fixed to the outer periphery at the notch 32a. The tip end 42 side of the shackle 4 is inserted and removed vertically through the insertion hole 21b of the case 2. When the shackle 4 is in the open position where it is pulled up together with the slide plate 3 relative to the case 2, it is hooked onto a switch operating section of the device and can then be pushed down together with the slide plate 3 to the closed position. When the tip end 42 of the shackle 4 is in a position facing the insertion hole 21b, the shackle 4 is provided with a notch 41a having a rotation-preventing flat portion perpendicular to the curved plane of the shackle 4 at a position corresponding to the notch 32a of the swivel tube portion 32.

[0015] The retaining member 5 is made of an elastic synthetic resin and is a ring-shaped body with a portion cut out, and is press-fitted into the notch 41a of the shackle 4 exposed from the notch 32a of the swivel cylinder 32, and rotates integrally with the shackle 4. The retaining member 5 is provided with a downward stop projection 51 that projects from the notch 32a of the swivel cylinder 32.

[0016] The insides of the front plate 23 and the rear plate 24 of the case 2 are provided with recesses 23b, 24b having an arc-shaped cross section that receive the swivel tube 32 of the slide plate 3 so that it can move up and down. Detachment step portions 23c, 24c are formed in the recesses 23b, 24b at positions that correspond to the lower surface of the retaining member 5. The detent protrusion 51 rotates on the detent step portions 23c, 24c. As shown in Figures 9 and 11, the detent step portions 23c, 24c are joined to each other to form a generally C-shaped abutment surface that opens toward the insertion hole 21b. 9, when the downward stop projection 51 is positioned above the open portion C, that is, when the tip 42 of the shackle 4 is positioned opposite the insertion hole 21b of the case 2, the downward stop steps 23c, 24c allow the shackle 4 and the slide plate 3 to descend, and at other rotation angle positions, the downward stop projection 51 abuts against the underside of the downward stop projection 51 to prevent the shackle 4 and the slide plate 3 from descending. For example, as shown in FIGS. 10 and 11, when the tip 42 of the shackle is positioned not opposite the insertion hole 21b of the case 2, the downward stop projection 51 of the retaining member 5 is on the downward stop projections 23c, 24c, and therefore the shackle 4 cannot be pushed down.

[0017] The inner surface of the case body 27 and the slide plate 3 are provided with positioning means consisting of a notch 23d and a notch claw 31b that elastically engage with each other when the slide plate 3 is in the closed position and when it is in the open position.

[0018] As described above, the multiple locking device 1 is made up of five components: the case body 27, case lid 28, slide plate 3, shackle 4, and retaining member 5, and is easy to manufacture and assemble. If all five components are made from synthetic resin molded bodies, or if only the shackle 4 is made from metal, there will be no metal-to-metal contact between the components, preventing metal contamination. [Explanation of symbols]

[0019] 1. Multiple locking device 2 cases 21 Upper plate 21a Swivel hole 21b Insertion hole 22 Lower plate part 23 Front plate part 23a Through hole 23b Recess 23c Lower stopper step 23d notch 24 Rear plate part 24a through hole 25 Side plate part 25a Standing piece 25b Standing piece 26 Side plate part 26a Standing piece 26b Standing piece 27 Case body 28 Case lid 3 Slide plate 31 Flat plate part 31a Through hole 31b Notched claw 32 Swivel tube 32a Notch 4 Shackles 41 Proximal end 42 Tip 5. Anti-slip member 51 Lowering stop protrusion

Claims

1. a case having an upper plate portion, a lower plate portion opposing the upper plate portion, a front plate portion, a rear plate portion opposing the front plate portion, and left and right side plate portions, the case having a plurality of through holes formed therein that pass through the front plate portion and the rear plate portion in the front-rear direction; a slide plate having a plurality of through holes formed at positions corresponding to the through holes of the case, the slide plate being housed in the case so as to move up and down between a closed position where the slide plate is pushed down relative to the case and an open position where the slide plate is pulled up; a shackle having a base end inserted into a swivel hole in the upper plate of the case, rotatable about an axis relative to the slide plate and fixed in the axial direction, and a tip end inserted into and removed from an insertion hole in the upper plate of the case in the up-down direction; the shackle is adapted to be latched to a switch operating portion of the device at an open position where the shackle is pulled up together with the slide plate relative to the case, and then be pushed down together with the slide plate to a closed position, In a multiple locking device for a lockout system, when the slide plate together with the shackle is in a closed position where the slide plate is pressed down against the case, the other end of the shackle is inserted into the insertion hole, and all of the through holes of the case and the through holes of the slide plate are aligned so that a padlock can be latched in the through holes, The slide plate includes a flat plate portion having the through hole and a swivel tube portion through which the base end side of the shackle is inserted, The swivel tube portion has a notch in the middle, The base end side of the shackle is prevented from coming off in the axial direction by a retaining member fixed to the outer periphery of the swivel cylinder portion at a position corresponding to the notch portion, The retaining member includes a lowering stop protrusion protruding from the notch of the swivel tube portion, A multiple locking device characterized in that a lowering stop step is formed on the inside of the case, which allows the shackle and slide plate to descend without abutting on the lowering stop protrusion when the tip of the shackle is in an axial rotation position facing the insertion hole of the case, and which abuts on the underside of the lowering stop protrusion to prevent the shackle and slide plate from descending at other rotation angle positions.

2. 2. The multiple locking device according to claim 1, wherein when the slide plate together with the shackle is in an open position pulled up relative to the case, all of the through holes of the case and all of the through holes of the slide plate are misaligned, making it impossible to latch a padlock in the through holes.

3. The case is composed of a main body and a lid, both of which are integrally molded from synthetic resin and snap-engaged together in the front-rear direction to form a box-like body, The main body includes the upper plate portion, the lower plate portion, the front plate portion, and upright pieces on the left and right side edges of the front plate portion, the cover body includes the rear plate portion and left and right standing pieces that stand on left and right side edges of the rear plate portion and are joined to standing pieces of the main body to form the side plate portions, The shackle has a notch having a rotation-preventing flat surface perpendicular to the curved plane of the shackle at a position corresponding to the notch of the swivel cylinder when the tip end is in a position facing the insertion hole, the retaining member is a partially cut-out ring made of elastic synthetic resin that is press-fitted and fixed to the cut-out portion of the shackle that is exposed through the cut-out portion of the swivel cylinder portion, 2. The multiple locking device according to claim 1, wherein the multiple locking device is comprised of five members: the case body, the lid, the slide plate, the shackle, and the retaining member.

4. 2. The multiple lock device according to claim 1, wherein the inner surface of the case and the slide plate are provided with positioning means consisting of a notch and a notch pawl that elastically engage with each other when the slide plate is in the closed position and when the slide plate is in the open position.

5. 4. The multiple locking device according to claim 3, wherein all of the five members are made of synthetic resin.

6. 4. The multiple locking device according to claim 3, wherein only the shackle among the five members is made of metal, and the other four members are made of resin.

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