Sheet shutter

Abstract

To obtain a sheet shutter that allows the degree of wear of an engaging element to be known without measuring a thickness of the worn portion.SOLUTION: In a gear member, a plurality of engaging recesses that engage with engaging elements are formed in a circumferential direction in line. The engaging elements that approach from a tangential direction successively engage with the engaging recesses by rotation, and the engaging elements that are engaged with the engaging recesses are successively disengaged to move a sheet curtain vertically. In addition, a recess is formed in an engaging surface that contacts the engaging recess in the engaging element, which is surrounded by the contacting portion.SELECTED DRAWING: Figure 14

Description

[Technical field]

[0001] The present invention relates to a sheet shutter. [Background technology]

[0002] Patent Document 1 describes a sheet shutter having a frame composed of an upper frame and a side frame, a rotating shaft rotatably provided in the upper frame and connected to a driving means, a sheet suspended on the rotating shaft so as to be freely wound and unwound, and multiple guide blocks provided on both the left and right ends of the sheet. The guide blocks engage with guide rails in the side frames. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2016-89419 A Summary of the Invention

[0004] In conventional sheet shutters, multiple resin engaging elements (guide blocks) that engage with guide rails are provided at both ends of the sheet curtain (sheet). For example, there is a configuration in which a metal gear member is formed with multiple engaging recesses aligned in the circumferential direction for engaging with the engaging elements, and the engaging elements are moved in the circumferential direction of the gear member by rotating the metal gear member, thereby moving the sheet curtain up and down. In this configuration, when the sheet curtain is moved up and down by rotating the gear member, friction occurs between the engaging surface of the engaging element that comes into contact with the engaging recess of the gear member and the engaging recess of the gear member. This causes wear on the engaging surface of the engaging element.

[0005] Furthermore, a metal contact block is disposed on the opposite side of the gear member with the engaging element therebetween, which contacts the engaging element engaged in the engaging recess and restricts its movement when the engaging element moves radially outward of the gear member. In this configuration, when the gear member is rotated to move the sheet curtain up and down, friction occurs between the contact surface of the engaging element facing the contact block and the contact block. This causes wear on the contact surface of the engaging element.

[0006] An object of the present disclosure is to know the degree of wear of an engagement piece without measuring the thickness of the worn portion. [Means for solving the problem]

[0007] A sheet shutter according to a first aspect of the present disclosure comprises a sheet curtain to be wound up onto a winding roll, resin engaging elements attached to both ends of the sheet curtain and arranged in a row in the winding direction of the sheet curtain, and a metal gear member which has a plurality of engaging recesses arranged in a circumferential direction for engaging with the engaging elements, and which rotates to sequentially engage the engaging elements that are close to each other from the tangential direction with the engaging recesses and sequentially disengage the engaging elements that were engaged with the engaging recesses, thereby winding or unwinding the sheet curtain onto or from the winding roll and moving the sheet curtain up and down, and is characterized in that the engaging surface of the engaging elements that come into contact with the engaging recesses has a recess formed thereon that is surrounded by the contacting portion.

[0008] According to the above configuration, a recess surrounded by the contacting portion is formed on the engagement surface of the engaging element that contacts the engaging recess. Therefore, the user can know the degree of wear of the engagement surface by looking at the recess and the degree of change in the depth of the recess. In other words, the user can know the degree of wear of the engagement surface of the engaging element without measuring the thickness of the worn portion.

[0009] A sheet shutter according to a second aspect of the present disclosure is the sheet shutter according to the first aspect, characterized in that the recess is recessed in a stepped shape.

[0010] According to the above configuration, the recess is recessed in a stepped manner, so that the user can know the degree of wear of the engagement surface in stages when the first recess disappears due to wear of the engagement surface and when the second recess disappears due to wear of the engagement surface.

[0011] The sheet shutter according to a third aspect of the present disclosure is characterized in that, in the sheet shutter described in the first or second aspect, it is provided with a pair of guide rails extending in the vertical direction at both ends of the sheet curtain, supporting the engaging element so that it can move up and down, and having an opening formed therein that allows the recess formed in the engaging element to be viewed.

[0012] According to the above-mentioned configuration, the guide rail is formed with an opening through which the recess formed on the engagement surface of the engagement element can be visually observed, so that the user can know the degree of wear on the engagement surface of the engagement element without removing the engagement element from the guide rail.

[0013] A sheet shutter according to a fourth aspect of the present disclosure is a sheet shutter according to any one of the first to third aspects, characterized in that the recess forms a material mark indicating the resin material of the engaging element.

[0014] According to the above configuration, the material mark indicating the resin material of the engaging part is formed by the recessed part, which makes it possible to prevent the material mark from becoming difficult to see due to wear of the engaging surface, compared to a case in which the material mark indicating the resin material of the engaging part is formed by the protruding part.

[0015] A sheet shutter according to a fifth aspect of the present disclosure comprises a sheet curtain to be wound up on a winding roll, resin engaging elements attached to both ends of the sheet curtain and arranged in a row in the winding direction of the sheet curtain, and a gear member which rotates to sequentially engage the engaging elements approaching from the tangential direction with the engaging recesses and sequentially disengage the engaging elements that were engaged with the engaging recesses, thereby winding or unwinding the sheet curtain onto or from the winding roll, thereby moving the sheet curtain up and down, and a metal contact block which is positioned on the opposite side of the gear member with the engaging element therebetween and comes into contact with the engaging element engaged with the engaging recess when it moves radially outward of the gear member, and is characterized in that a recess surrounded by a contacting portion is formed on the contact surface of the engaging element that comes into contact with the contact block.

[0016] According to the above configuration, a recess surrounded by the contacting portion is formed on the contact surface of the engaging element that contacts the contact block. Therefore, the user can know the degree of wear of the contact surface by looking at the recess and the degree of change in the depth of the recess. In other words, the user can know the degree of wear of the contact surface of the engaging element without measuring the thickness of the worn portion.

[0017] A sheet shutter according to a sixth aspect of the present disclosure is the sheet shutter according to the fifth aspect, characterized in that the recess is recessed in a stepped shape.

[0018] According to the above configuration, the recess is recessed in a stepped manner, so that the user can know the degree of wear of the contact surface in stages from when the first recess disappears due to wear of the contact surface and when the second recess disappears due to wear of the contact surface.

[0019] The sheet shutter according to a seventh aspect of the present disclosure is characterized in that, in the sheet shutter described in the fifth or sixth aspect, it is provided with a pair of guide rails extending in the vertical direction at both ends of the sheet curtain, supporting the engaging element so that it can move up and down, and having an opening formed therein that allows the recess formed in the engaging element to be viewed.

[0020] According to the above-mentioned configuration, the guide rail is formed with an opening through which the recess formed on the contact surface of the engaging element can be visually confirmed, so that the user can know the degree of wear on the contact surface of the engaging element without removing the engaging element from the guide rail.

[0021] A sheet shutter according to an eighth aspect of the present disclosure is a sheet shutter according to any one of the fifth to seventh aspects, characterized in that the recess forms a material mark indicating the resin material of the engaging element.

[0022] According to the above configuration, the material mark indicating the resin material of the engaging part is formed by the recessed part, which makes it possible to prevent the material mark from becoming difficult to see due to wear of the contact surface, compared to a case in which the material mark indicating the resin material of the engaging part is formed by the protruding part. Effect of the Invention

[0023] According to the present disclosure, the degree of wear of the engagement piece can be known without measuring the thickness of the worn portion. [Brief description of the drawings]

[0024] [Figure 1] FIG. 1 is a perspective view showing a sheet shutter according to a first embodiment of the present disclosure. [Diagram 2] FIG. 2 is a perspective view showing a main part of the sheet shutter according to the first embodiment of the present disclosure. [Diagram 3] 1 is a cross-sectional view showing a main part of a sheet shutter according to a first embodiment of the present disclosure, viewed from above. [Figure 4]1 is a perspective view showing a guide rail, a side frame, etc., provided in a sheet shutter according to a first embodiment of the present disclosure. FIG. [Diagram 5] FIG. 2 is an exploded perspective view showing a main part of the sheet shutter according to the first embodiment of the present disclosure. [Figure 6] 1 is a perspective view showing a curtain unit provided in a sheet shutter according to a first embodiment of the present disclosure. FIG. [Figure 7] 1 is a perspective view showing a curtain unit provided in a sheet shutter according to a first embodiment of the present disclosure. FIG. [Figure 8] 1A and 1B are a plan view and a side view showing an engagement element provided on a sheet shutter according to a first embodiment of the present disclosure. [Figure 9] 1 is an exploded perspective view showing a curtain unit provided in a sheet shutter according to a first embodiment of the present disclosure. FIG. [Figure 10] 12 is an enlarged cross-sectional view showing a main part of the sheet shutter according to the first embodiment of the present disclosure, in which a portion G01 in FIG. 11 is enlarged. FIG. [Figure 11] 1 is a cross-sectional view showing a main part of a sheet shutter according to a first embodiment of the present disclosure, as viewed from the side. [Figure 12] 1 is a perspective view showing an engagement element provided on a sheet shutter according to a first embodiment of the present disclosure. FIG. [Figure 13] 3A and 3B are cross-sectional views showing recesses of an engagement element provided in the sheet shutter according to the first embodiment of the present disclosure. [Figure 14] 1 is a perspective view showing an engagement element provided on a sheet shutter according to a first embodiment of the present disclosure. FIG. [Figure 15] 1 is a perspective view showing a guide rail, a side frame, etc., provided in a sheet shutter according to a first embodiment of the present disclosure. FIG. [Figure 16] 13 is a perspective view showing an engagement element provided on a sheet shutter according to a modified embodiment of the present disclosure. FIG. [Figure 17]13 is a perspective view showing an engagement element provided on a sheet shutter according to a modified embodiment of the present disclosure. FIG. [Figure 18] 11 is a cross-sectional view showing a main part of a sheet shutter according to a second embodiment of the present disclosure, viewed from above. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] First Embodiment An example of a sheet shutter according to a first embodiment of the present disclosure will be described with reference to Fig. 1 to Fig. 17. Note that, in the drawings, arrow H indicates the up-down direction (vertical direction) of the sheet shutter, arrow W indicates the width direction (horizontal direction) of the sheet shutter, and arrow L indicates the depth direction (horizontal direction) of the sheet shutter.

[0026] (Overall composition) The sheet shutter 10 is a sheet shutter that is attached to the entrance of a warehouse or the like, and as shown in Figures 1 and 2, includes a frame 12, a take-up roll 20, a curtain unit 30, a drive roll 60, and a contact block 80. The frame 12, the take-up roll 20, the curtain unit 30, the drive roll 60, and the contact block 80 are symmetrical with respect to a center line CL11 of the sheet shutter 10 in the width direction of the sheet shutter 10 (hereinafter referred to as the "shutter width direction").

[0027] [Frame 12] The frame 12 includes a pair of side frames 22 and a shutter case 18. The pair of side frames 22 each extend in the vertical direction of the sheet shutter 10 (hereinafter, the "shutter vertical direction") and are disposed on both sides of the carry-in entrance in the shutter width direction, at both ends of the curtain unit 30 in the shutter width direction.

[0028] Furthermore, guide rails 14 extending in the vertical direction are attached to the pair of side frames 22, respectively. The pair of guide rails 14 guide the curtain unit 30 in the vertical direction so that the curtain unit 30 moves in the vertical direction.

[0029] Specifically, a cross section of the side frame 22 cut in a direction perpendicular to the longitudinal direction has a C-shape with an opening on the inside in the shutter width direction (the side approaching the center line CL11 in the shutter width direction of the sheet shutter 10) as shown in Fig. 3. Furthermore, the side frame 22 is formed with a plurality of through holes 22a penetrating in the shutter width direction at intervals in the vertical direction.

[0030] A cross section of the guide rail 14 cut in a direction perpendicular to the longitudinal direction is U-shaped with an opening on the inside in the shutter width direction, and a pair of recesses 14a into which both ends of the side frame 22 fit are formed on the outer portion of the guide rail 14 in the shutter width direction. Furthermore, a plurality of female threaded holes 14b that open on the outside in the shutter width direction are formed at intervals in the vertical direction on the outer portion of the guide rail 14 in the shutter width direction. The guide rail 14 is attached to the side frame 22 by passing a screw 82 through the through hole 22a and tightening it into the female threaded hole 14b.

[0031] Furthermore, a pair of flanges 16 are formed on the inner side of the guide rail 14 in the shutter width direction to narrow the opening width. An engagement piece 40 (described in detail later) constituting the curtain unit 30 is supported inside the guide rail 14 so as to be movable in the up and down direction.

[0032] The guide rail 14 is also formed with an opening 24a (see FIG. 4) that allows a recess 56, described later, formed in the engaging piece 40 to be viewed from the outside, and an opening 26a (see FIG. 15) that allows a recess 52, described later, formed in the engaging piece 40 to be viewed from the outside. The openings 24a and 26a formed in the guide rail 14 will be described in detail later.

[0033] 1, the shutter case 18 is disposed extending in the shutter width direction so as to connect the upper ends of the pair of side frames 22. A cross section of the shutter case 18 cut in a direction perpendicular to the longitudinal direction has a rectangular tubular shape extending from above the side frame 22 to one side (the right side in the figure) in the depth direction of the sheet shutter 10 (hereinafter, "shutter depth direction"), and the inside of the shutter case 18 is hollow.

[0034] [Winding roll 20] As shown in FIG. 2, the winding roll 20 is disposed inside the shutter case 18 at one side in the shutter depth direction.

[0035] The winding roll 20 extends in the shutter width direction, and the axial direction of the winding roll 20 is the shutter width direction. Furthermore, the winding roll 20 is rotatably supported by a frame member (not shown). The winding roll 20 is biased by a biasing member (not shown) so as to rotate in a direction in which the curtain unit 30 is wound up (hereinafter referred to as the "winding direction").

[0036] In this configuration, a force acts on the curtain unit 30 in the direction in which it is wound by the winding roll 20 .

[0037] [Curtain Unit 30] The curtain unit 30 is disposed between a pair of side frames 22 as shown in Fig. 1 in a state in which the entrance of a warehouse or the like is closed. Also, as shown in Fig. 2, the curtain unit 30 includes a sheet curtain 32 and a pair of wires 36 (see Fig. 6) provided at both end portions of the sheet curtain 32 in the shutter width direction. Furthermore, the curtain unit 30 includes a plurality of engaging pieces 40 attached to both end portions of the sheet curtain 32 in the shutter width direction and arranged side by side in the moving direction (rolling direction) of the sheet curtain 32, and screws 38 (see Fig. 6) for attaching the engaging pieces 40 to the sheet curtain 32.

[0038] -32 sheet curtains, 36 wires- The sheet curtain 32 is made of a resin material and has a rectangular shape extending in the moving direction of the sheet curtain 32. An end of the sheet curtain 32 in the moving direction is attached to the winding roll 20.

[0039] 3 and 6, both end portions of the sheet curtain 32 in the shutter width direction are folded back. Furthermore, the tip of the folded back portion is fused to the other overlapping portion of the sheet curtain 32. As a result, a hollow portion 32a is formed at the base end of the folded back portion of the sheet curtain 32.

[0040] The wire 36 is disposed in the hollow portion 32a and extends in the moving direction of the sheet curtain 32, and is provided at both end portions in the shutter width direction of the sheet curtain 32. The wire 36 is formed by twisting together a plurality of wires such as steel wires. In this manner, by disposing the wire 36 in the hollow portion 32a, the both end portions in the shutter width direction of the sheet curtain 32 bulge in the thickness direction of the sheet curtain 32 compared to other portions.

[0041] -Engagement piece 40, screw 38- The engaging elements 40 are attached to both end portions of the sheet curtain 32 in the shutter width direction, and as shown in Figures 6 and 7, a plurality of engaging elements 40 are lined up in the moving direction of the sheet curtain 32. In other words, a plurality of engaging elements 40 are lined up in the winding direction of the sheet curtain 32.

[0042] The engaging element 40 is integrally molded using a resin material (polyacetal (POM) in this embodiment). When the engaging element 40 is disposed inside the guide rail 14, as shown in Figs. 3 and 8(A) , the engaging element 40 has a rectangular shape with a U-shaped groove 42 that opens on the inside in the shutter width direction when viewed from above. Furthermore, protrusions 44 are formed on the opening ends of the grooves 42.

[0043] A gradually changing portion 42a is formed on the inner side of the groove 42 in the shutter width direction, where the opening width gradually widens toward the inside in the shutter width direction when viewed from above. Also, an elliptical circular portion 42b with a wider width is formed on the outer side of the groove 42 in the shutter width direction (the side away from the center line CL11 of the sheet shutter 10 in the shutter width direction) when viewed from above. The portions of both ends of the sheet curtain 32 in the shutter width direction that are expanded by the wire 36 are disposed in this circular portion 42b (see FIG. 3).

[0044] Furthermore, the engaging element 40 is formed with a side surface 40a facing outward in the shutter width direction, and a through hole 46 having a circular cross section that penetrates from the side surface 40a to the circular portion 42b of the groove portion 42. An expanding diameter portion 46a whose diameter gradually expands toward the outside in the shutter width direction is formed in the outer portion of this through hole 46 in the shutter width direction. As shown in Figures 6 and 9, a screw 38 is inserted into this through hole 46 from the outside in the shutter width direction, and the tip side portion of the screw 38 is screwed into the wire 36, whereby the engaging element 40 is attached to both end portions in the shutter width direction of the sheet curtain 32 (see Figure 3).

[0045] 8(B) and 10, the engaging element 40 is formed with a contact portion 50 that comes into contact with the contact block 80, and an engaging portion 54 that engages with an engaging recess 66 of a gear member 64 provided in the driving roll 60. The shapes of the contact portion 50 and the engaging portion 54 of the engaging element 40 will be described in detail later.

[0046] 3, with the tip portion of the screw 38 screwed into the wire 36, the head of the screw 38 is disposed in the expanded diameter portion 46a of the through hole 46. As a result, the head of the screw 38 fits into the expanded diameter portion 46a of the through hole 46 and does not protrude from the side surface 40a of the engaging element 40.

[0047] [Drive roll 60] 2, the drive roll 60 is disposed inside the shutter case 18, at the other side in the shutter depth direction, and above the pair of guide rails 14. In addition, a part of the curtain unit 30 that can be wound by the winding roll 20 or that can be unwound from the winding roll 20 is wound around the drive roll 60.

[0048] The driving roll 60 extends in the shutter width direction, and the axial direction of the driving roll 60 is the shutter width direction. The driving roll 60 is rotatably supported by a frame member (not shown). The driving roll 60 includes a roll body 62 extending in the shutter width direction, and a pair of gear members 64 attached to both ends of the roll body 62 in the shutter width direction.

[0049] The gear member 64 is made of metal and has an annular shape as shown in Fig. 5, and a plurality of engaging recesses 66 for engaging with the engaging portions 54 of the engaging elements 40 are formed side by side in the circumferential direction on the outer circumferential surface of the gear member 64. Also, a flange 78 is formed on the outer portion of the gear member 64 in the shutter width direction, protruding radially outward relative to other portions.

[0050] 10, the engagement recess 66 has a pair of side planes 66a formed on both end portions in the gear circumferential direction, and a bottom surface 66b sandwiched between the pair of side planes 66a and facing outward in the radial direction of the gear member 64 (hereinafter referred to as the "gear radial direction"). The side planes 66a are flat, and the bottom surface 66b is curved and convex inward in the gear radial direction.

[0051] Further, the driving roll 60 is adapted to rotate in both positive and negative directions by the driving force of a motor (not shown).

[0052] [Contact block 80] The contact blocks 80 are made of metal, and are disposed inside the shutter case 18 at the other side in the shutter depth direction and at both end portions in the shutter width direction, as shown in Fig. 2. Specifically, the contact blocks 80 are disposed on the opposite side of the gear member 64 with the engaging piece 40 therebetween, as shown in Fig. 11.

[0053] The contact block 80 is formed in an arc shape and is attached to a frame member (not shown). The contact block 80 has an inner peripheral surface 80a facing the gear member 64 side.

[0054] In this configuration, when the engaging element 40 engaged with the engaging recess 66 of the gear member 64 moves outward in the gear radial direction, the inner circumferential surface 80a of the contact block 80 comes into contact with the contact portion 50 of the engaging element 40. This maintains the engagement between the engaging recess 66 of the gear member 64 and the engaging element 40.

[0055] (Overall structure) When the entrance of a warehouse or the like is closed by the curtain unit 30, and the driving roll 60 shown in Fig. 11 rotates in the forward direction (K01 direction shown in Fig. 11) by the rotational force transmitted from the motor, the rotating gear member 64 sequentially engages the engaging elements 40 approaching from the tangential direction (F01 in the figure) with the engaging recesses 66. Furthermore, the rotating gear member 64 sequentially disengages the engaging elements 40 that were engaged with the engaging recesses 66, and the disengaged engaging elements 40 move away in the tangential direction (F02 in the figure). The rotating gear member 64 also causes the curtain unit 30 to be taken up by the take-up roll 20 (see Fig. 2).

[0056] Then, the portion of the curtain unit 30 blocking the carrying entrance moves upward while being guided by the pair of guide rails 14 shown in Fig. 2. Specifically, the movement of the engaging members 40 of the curtain unit 30 shown in Fig. 3 in the shutter depth direction and the shutter width direction is restricted by the guide rails 14, so that the curtain unit 30 moves upward while being guided by the pair of guide rails 14. In this way, the carrying entrance of the warehouse or the like is opened by the curtain unit 30.

[0057] In contrast, when the entrance of a warehouse or the like is opened by the curtain unit 30 and the drive roll 60 shown in Figure 11 rotates in the negative direction (K02 direction shown in Figure 11) as the rotational force from the motor is transmitted, the rotating gear member 64 sequentially engages the engaging elements 40 approaching from the tangential direction (F11 in the figure) with the engaging recesses 66, causing the curtain unit 30 to be unwound from the winding roll 20 (see Figure 2).

[0058] Furthermore, the rotating gear member 64 sequentially disengages the engaging elements 40 that were engaged with the engaging recesses 66, and the disengaged engaging elements 40 move away in the tangential direction (F12 in the figure). The rotating gear member 64 also moves the curtain unit 30 downward. Specifically, the movement of the engaging elements 40 of the curtain unit 30 shown in FIG. 3 in the shutter depth direction and shutter width direction is restricted by the guide rails 14, so that the curtain unit 30 moves downward while being guided by the pair of guide rails 14. As a result, the entrance of a warehouse or the like is blocked by the curtain unit 30.

[0059] (Main part configuration) Next, the contact portion 50 and engagement portion 54 of the engagement element 40 and the openings 24a, 26a formed in the guide rail 14 will be described. Note that the shape of the engagement element 40 will be described using the direction in a state in which the engagement portion 54 of the engagement element 40 is engaged with the engagement recess 66 of the gear member 64. Specifically, the arrow X shown in Fig. 8(B) indicates the gear radial direction, and the arrow Y indicates the circumferential direction of the gear member 64 (hereinafter referred to as the "gear circumferential direction").

[0060] 8(B), when viewed from the shutter width direction, the engaging element 40 is symmetrical with respect to a center line CL01 that passes through the center point of the through hole 46 and extends in the gear radial direction. The engaging element 40 is formed with a pair of side surfaces 40b that face in the gear circumferential direction.

[0061] Furthermore, in the engaging element 40, a contact portion 50 that comes into contact with a contact block 80 (see FIG. 11) is formed on the outer side in the gear radial direction (the side away from the rotation center of the gear member 64) with respect to the pair of side faces 40b. Also, in the engaging element 40, an engaging portion 54 that engages with an engaging recess 66 (see FIG. 11) of the gear member 64 is formed on the inner side in the gear radial direction (the side approaching the rotation center of the gear member 64) with respect to the pair of side faces 40b.

[0062] [Contact portion 50 of engagement element 40] As shown in Figures 8(B) and 10, when viewed from the shutter width direction, the contact portion 50 of the engaging element 40 has a convex curved surface 50a formed on both end portions in the gear circumferential direction, and a contact surface 50b sandwiched between the pair of curved surfaces 50a, facing outward in the gear radial direction, and in contact with the inner surface 80a of the contact block 80 (see Figure 10).

[0063] As shown in Fig. 12, the contact surface 50b has a recess 52 surrounded by a portion that contacts the inner peripheral surface 80a (see Fig. 10) of the contact block 80. When viewed from the gear radial direction, the recess 52 has a rectangular shape extending in the shutter width direction, and is recessed in a stepped manner (see Fig. 13(A)). Specifically, a first recess 52a is formed on both sides in the shutter width direction, and a second recess 52b is formed in a central portion in the shutter width direction. In this embodiment, as an example, the depth of the recess 52a is 0.8 [mm], and the depth of the recess 52b is 1.6 [mm].

[0064] In this configuration, when the engaging element 40 engaged with the engaging recess 66 moves outward in the gear radial direction, the contact surface 50b of the contact portion 50 of the engaging element 40 comes into contact with the inner peripheral surface 80a of the contact block 80. This maintains the engaged state between the engaging portion 54 of the engaging element 40 and the engaging recess 66 of the gear member 64.

[0065] Furthermore, the contact surface 50b of the contact portion 50 is worn down due to contact with the inner circumferential surface 80a of the contact block 80. Due to this wear, the depth of the recess 52 becomes shallower compared to when the recess 52 is not worn down.

[0066] [Engagement portion 54 of engagement piece 40] 8(B) and 10, the engaging portion 54 of the engaging piece 40 is formed with a pair of first engaging surfaces 54a formed on both end portions in the gear circumferential direction, and a second engaging surface 54b sandwiched between the pair of first engaging surfaces 54a, facing inward in the gear radial direction, and in contact with a bottom surface 66b (see FIG. 10) of the engaging recess 66. The second engaging surface 54b is an example of an engaging surface.

[0067] The first engagement surface 54a has a flat shape and is inclined when viewed from the shutter width direction. Specifically, the first engagement surface 54a is inclined with respect to the center line CL01 so as to approach the center line CL01 from the outer side to the inner side in the gear radial direction. Moreover, the second engagement surface 54b has a curved shape with a convex inner side in the gear radial direction when viewed from the shutter width direction.

[0068] As shown in Fig. 14, the second engagement surface 54b has a recess 56 surrounded by a portion that contacts the bottom surface 66b (see Fig. 10) of the engagement recess 66. The recess 56 has a rectangular shape extending in the shutter width direction when viewed from the gear radial direction, and is recessed in a stepped manner (see Fig. 13(B)). Specifically, a first recess 56a is formed on both sides in the shutter width direction, and a second recess 56b is formed in a central portion in the shutter width direction. In this embodiment, as an example, the depth of the recess 56a is 0.8 [mm], and the depth of the recess 56b is 1.6 [mm].

[0069] In this configuration, as shown in Figure 10, when the engagement portion 54 of the engagement piece 40 engages with the engagement recess 66 to move the curtain unit 30 up and down, the bottom surface 66b of the engagement recess 66 comes into surface contact (hereinafter referred to as "surface contact") with the second engagement surface 54b of the engagement piece 40.

[0070] Furthermore, in a state in which the engaging portion 54 of the engaging piece 40 is engaged with the engaging recess 66 to move the curtain unit 30 up and down, one first engaging surface 54a and one side flat surface 66a of the engaging recess 66 are in surface contact with each other, and the other first engaging surface 54a and the other side flat surface 66a of the engaging recess 66 are separated from each other. In other words, a gap is formed between the other side flat surface 66a and the other first engaging surface 54a.

[0071] Furthermore, the second engagement surface 54b of the engagement portion 54 comes into contact with the bottom surface 66b of the engagement recess 66, causing wear to the second engagement surface 54b of the engagement portion 54. Due to this wear, the depth of the recess 56 becomes shallower compared to when the recess 56 is not worn.

[0072] [Opening 24a of guide rail 14] 3, a cross section of the guide rail 14 cut in a direction perpendicular to the longitudinal direction has a U-shape with an opening on the inside in the shutter width direction. The guide rail 14 has a side plate 24 arranged on one side in the shutter depth direction (upper side in the figure) relative to an engaging element 40 arranged inside, and a side plate 26 arranged on the other side in the shutter depth direction (lower side in the figure) relative to the engaging element 40 arranged inside.

[0073] 4, a U-shaped opening 24a that is open on the inside in the shutter width direction when viewed from the shutter depth direction is formed in the side plate 24 of the guide rail 14. The height of the opening 24a from the ground is, for example, 2 m to 2.5 m.

[0074] In this configuration, a user who uses the sheet shutter 10 can visually recognize the recess 56 (see FIG. 14) formed in the second engagement surface 54b from the outside through the opening 24a.

[0075] [Opening 26a of guide rail 14] 15, a U-shaped opening 26a that is open on the inside in the shutter width direction when viewed from the shutter depth direction is formed in the side plate 26 of the guide rail 14. The height of the opening 26a from the ground is, for example, 2 m or more and 2.5 m or less.

[0076] In this configuration, a user using the sheet shutter 10 can view the recess 52 (see FIG. 12) formed on the contact surface 50b from the outside through the opening 26a.

[0077] (Function of main components) Next, the operation of the main components will be described.

[0078] 2 is biased to rotate in a winding direction to wind up the curtain unit 30. Therefore, a force acts on the curtain unit 30 to wind it up by the winding roll 20. However, when the rotation of the drive roll 60 is stopped, the rotation of the winding roll 20 is restricted by a restricting means (not shown).

[0079] 11, the engaging portion 54 of the engaging element 40 of the curtain unit 30 engages with the engaging recess 66 of the gear member 64. Furthermore, when the engaging element 40 engaged with the engaging recess 66 moves outward in the gear radial direction, the contact portion 50 of the engaging element 40 comes into contact with the inner peripheral surface 80a of the contact block 80. This maintains the engaged state between the engaging portion 54 and the engaging recess 66. In other words, the state in which the entrance of the warehouse or the like is blocked by the curtain unit 30, or the state in which the entrance of the warehouse or the like is opened by the curtain unit 30, is maintained.

[0080] Here, when the entrance of a warehouse or the like is blocked by the curtain unit 30, when the drive roll 60 is rotated in the forward direction (K01 direction shown in Figure 11), the engaging member 40 engaged with the engaging recess 66 of the gear member 64 rotates in the forward direction.

[0081] As a result, the engaging elements 40 approaching from the tangential direction (F01 in the figure) of the gear member 64 sequentially engage with the engaging recesses 66. Furthermore, the engaging elements 40 that were engaged with the engaging recesses 66 are sequentially disengaged and move away in the tangential direction (F02 in the figure) of the gear member 64. As a result, the rotating gear member 64 causes the curtain unit 30 to be taken up by the take-up roll 20 (see FIG. 2).

[0082] Then, the portion of the curtain unit 30 blocking the carrying entrance moves upward while being guided by the pair of guide rails 14 (see FIG. 2). Specifically, the movement of the engaging members 40 of the curtain unit 30 in the shutter depth direction and the shutter width direction is restricted by the guide rails 14, so that the curtain unit 30 moves upward while being guided by the pair of guide rails 14. In this way, the carrying entrance of the warehouse or the like is opened by the curtain unit 30.

[0083] In contrast, when the entrance of a warehouse or the like is opened by the curtain unit 30 and the drive roll 60 is rotated in the negative direction (K02 direction shown in Figure 11), the engaging member 40 engaged with the engaging recess 66 of the gear member 64 rotates in the negative direction.

[0084] As a result, the engaging elements 40 approaching from the tangential direction (F11 in the figure) of the gear member 64 sequentially engage with the engaging recesses 66. Furthermore, the engaging elements 40 that were engaged with the engaging recesses 66 are sequentially disengaged and move away in the tangential direction (F12 in the figure) of the gear member 64. As a result, the rotating gear member 64 unwinds the curtain unit 30 from the winding roll 20 (see FIG. 2).

[0085] Then, the curtain unit 30 moves downward while being guided by the pair of guide rails 14 (see FIG. 2). Specifically, the movement of the engagement members 40 of the curtain unit 30 in the shutter depth direction and the shutter width direction is restricted by the guide rails 14, so that the curtain unit 30 moves downward while being guided by the pair of guide rails 14. In this way, the entrance of the warehouse or the like is closed by the curtain unit 30.

[0086] Here, when the rotating gear member 64 applies a moving force to the engagement member 40, friction occurs between the second engagement surface 54b of the engagement member 40 and the bottom surface 66b of the engagement recess 66. Furthermore, when the engagement member 40 moves inside the guide rail 14, friction occurs between the second engagement surface 54b of the engagement member 40 and the side plate 24 of the guide rail 14. This friction causes the second engagement surface 54b of the engagement member 40 to wear out.

[0087] A user who uses the sheet shutter 10 can visually check the recess 56 (see FIG. 14) formed on the second engagement surface 54b from the outside through the opening 24a of the side plate 24 shown in FIG. 4, thereby knowing the degree of wear of the second engagement surface 54b of the engagement piece 40. Specifically, the user can know the degree of wear of the second engagement surface 54b from the degree of change in the depth of the recess 56.

[0088] In the present embodiment, for example, the depth of the recess 56a is 0.8 [mm], and the depth of the recess 56b is 1.6 [mm]. Therefore, for example, when the recess 56a disappears due to wear of the second engagement surface 54b, the user can prepare a replacement curtain unit 30, and when the recess 56b disappears due to wear of the second engagement surface 54b, the user can replace the already installed curtain unit 30 with the prepared curtain unit 30.

[0089] In addition, when the rotating gear member 64 applies a moving force to the engagement member 40, friction occurs between the contact surface 50b of the engagement member 40 and the inner peripheral surface 80a of the contact block 80. Furthermore, when the engagement member 40 moves inside the guide rail 14, friction occurs between the contact surface 50b of the engagement member 40 and the side plate 26 of the guide rail 14. This friction causes wear on the contact surface 50b of the engagement member 40.

[0090] A user who uses the sheet shutter 10 can visually check the recesses 52 (see FIG. 12) formed on the contact surface 50b from the outside through the openings 26a of the side plates 26 shown in FIG. 15, thereby knowing the degree of wear on the contact surface 50b of the engagement elements 40. Specifically, the user can know the degree of wear on the contact surface 50b from the degree of change in the depth of the recesses 52.

[0091] In the present embodiment, for example, the depth of the recess 52a is 0.8 [mm], and the depth of the recess 52b is 1.6 [mm]. Therefore, for example, when the recess 52a disappears due to wear of the contact surface 50b, the user can prepare a replacement curtain unit 30, and when the recess 52b disappears due to wear of the contact surface 50b, the user can replace the curtain unit 30 that has been prepared with the curtain unit 30 that has already been installed.

[0092] (summary) As described above, in the sheet shutter 10, the second engagement surface 54b that comes into contact with the bottom surface 66b of the engagement recess 66 in the engagement piece 40 has a recess 56 surrounded by the contacting portion. Therefore, by looking at the recess 56, the user can know the degree of wear of the second engagement surface 54b from the degree of change in the depth of the recess 56. In other words, the user can know the degree of wear of the second engagement surface 54b of the engagement piece 40 without measuring the thickness of the worn portion.

[0093] In addition, in the sheet shutter 10, the recess 56 is recessed in a stepped manner. Therefore, when the first recess 56a disappears due to wear of the second engagement surface 54b, and when the second recess 56b disappears due to wear of the second engagement surface 54b, the user can know the degree of wear of the second engagement surface 54b in stages.

[0094] In addition, in the sheet shutter 10, an opening 24a is formed in the guide rail 14, which allows the recess 56 formed in the second engagement surface 54b of the engagement piece 40 to be visually observed from the outside. Therefore, the user can know the degree of wear of the second engagement surface 54b of the engagement piece 40 without removing the engagement piece 40 from the guide rail 14.

[0095] In addition, in the sheet shutter 10, a recess 52 surrounded by the contacting portion is formed on the contact surface 50b of the engaging element 40, which contacts the inner peripheral surface 80a of the contact block 80. Therefore, the user can know the degree of wear of the contact surface 50b by looking at the recess 52 and the degree of change in the depth of the recess 52. In other words, the user can know the degree of wear of the contact surface 50b of the engaging element 40 without measuring the thickness of the worn portion.

[0096] In addition, in the sheet shutter 10, the recess 52 is recessed in a stepped manner. Therefore, when the first recess 52a disappears due to wear of the contact surface 50b, and when the second recess 52b disappears due to wear of the contact surface 50b, the user can know the degree of wear of the contact surface 50b in stages.

[0097] In addition, in the sheet shutter 10, an opening 26a is formed in the guide rail 14, which allows the recess 52 formed in the contact surface 50b of the engagement piece 40 to be visually observed from the outside. Therefore, the user can know the degree of wear of the contact surface 50b of the engagement piece 40 without removing the engagement piece 40 from the guide rail 14.

[0098] <Second embodiment> Next, an example of a sheet shutter according to a second embodiment will be described with reference to Fig. 18. Note that, with regard to the second embodiment, differences from the first embodiment will be mainly described.

[0099] (Sheet Curtain 232) The portions on both ends in the shutter width direction of the sheet curtain 232 of the sheet shutter 210 according to the second embodiment are folded back as shown in Fig. 18. Furthermore, a retainer 234 having a U-shaped cross section is provided to cover the ends of the overlapping portions of the folded back sheet curtain 232. This retainer 234 is elongated and extends along the edge of the sheet curtain 232, and holds the end of the sheet curtain 232 in place.

[0100] The retainer 234 is formed with through holes (reference numerals omitted) spaced apart in the longitudinal direction and penetrating in the depth direction. Furthermore, the sheet curtain 232 is also provided with through holes (reference numerals omitted) penetrating in the depth direction at portions overlapping with the through holes of the retainer 234 in the depth direction. (engager 240) 18, the engagement piece 240 of the sheet shutter 210 is rectangular when viewed from above, with a U-shaped groove 242 that opens on the inside in the shutter width direction. A retainer 234 attached to the end of the sheet curtain 232 is disposed in the groove 242.

[0101] Further, the engaging element 240 has a stepped through hole 242 that overlaps in the depth direction with the through hole formed in the retainer 234. The through hole 242 has a small diameter portion 242a and a large diameter portion 242b that is larger in diameter than the small diameter portion 242a, and the large diameter portion 242b faces the contact surface 50b of the engaging element 240 and the second engaging surface 54b.

[0102] A silver metallic rivet 250 is provided for attaching the engaging element 240 to the sheet curtain 232. Specifically, the rivet 250 is inserted into the through-hole 242 of the engaging element 240, the through-hole of the retainer 234, and the through-hole of the sheet curtain 232 from the second engaging surface 54b side, and the contact surface 50b side of the rivet 250 is crimped, thereby attaching the engaging element 240 to the sheet curtain 232.

[0103] In this state, the flange portion 250a of the rivet 250 is disposed on the large diameter portion 242b on the second engagement surface 54b side, and is recessed by one step with respect to the second engagement surface 54b. As a result, a recess 256 is formed in the second engagement surface 54b. The surface of the flange portion 250a facing outward is painted black.

[0104] Furthermore, the crimped portion 250b of the rivet 250 is disposed on the large diameter portion 242b on the contact surface 50b side, and is recessed from the contact surface 50b by one step, thereby forming a recess 252 on the contact surface 50b. The outer surface of the crimped portion 250b is painted black.

[0105] (summary) As described above, in the sheet shutter 210, the flange portion 250a of the rivet 250 that attaches the engaging element 240 to the sheet curtain 232 and the outward surface of the crimped portion 250b are painted black. As a result, the black paint peels off due to wear, revealing the silver color of the rivet 250, and the degree of wear of the contact surface 50b and the second engaging surface 54b can be known.

[0106] Although the present invention has been described in detail with respect to a specific embodiment, it is clear to those skilled in the art that the present invention is not limited to the embodiment, and various other embodiments are possible within the scope of the present invention. For example, in the first embodiment, the recess 56 formed in the second engagement surface 54b is rectangular when viewed from the gear radial direction, but as shown in Fig. 16, the recess 156 may be used to form a material mark indicating the resin material of the engagement element 40.

[0107] In this way, by using the recess 156 to form a material mark indicating the resin material of the engaging element 40, it is possible to prevent the material mark from becoming difficult to see due to wear of the second engaging surface 54b, compared to when a material mark indicating the resin material of the engaging element is formed using a protrusion.

[0108] In addition, in the above first embodiment, the recess 52 formed on the contact surface 50b is rectangular when viewed from the gear radial direction, but as shown in FIG. 17, the recess 152 may form a material mark indicating the resin material of the engaging element 40.

[0109] In this way, by using the recess 152 to form a material mark indicating the resin material of the engaging element 40, it is possible to prevent the material mark from becoming difficult to see due to wear of the contact surface 50b, compared to when a material mark indicating the resin material of the engaging element is formed using a protrusion.

[0110] Furthermore, in the first embodiment, the recesses 52, 56 are recessed in two stages, but they may be recessed in three or more stages.

[0111] In the first embodiment, the recesses 56 are formed in the second engagement surface 54b of the engagement piece 40. However, if the first engagement surface 54a is subject to wear, recesses may be formed in the first engagement surface 54a.

[0112] Although not specifically described in the first and second embodiments, the pair of gear members 64 may be integrally formed as a single gear member extending in the shutter width direction.

[0113] Although not specifically described in the first and second embodiments, the motor that generates the driving force transmitted to the driving roll 60 may be switched between operating and non-operating using a remote control or the like. [Explanation of symbols]

[0114] 10 Sheet Shutter 14 Guide rail 20 Winding roll 24a opening 26a aperture 32 Sheet Curtain 40 Engagement element 50b Contact surface 52 Recess 54b Second engagement surface (an example of an engagement surface) 56 Recess 64 Gear parts 66 Engagement recess 80 Contact Block 152 Recess 156 Recess 210 Sheet Shutter 232 Sheet Curtain 240 Engagement element 252 Recess 256 Recess

Claims

1. A sheet curtain wound on a winding roll; A plurality of resin engaging members are attached to both ends of the sheet curtain and arranged in a direction in which the sheet curtain is rolled up; a metal gear member that rotates to sequentially engage the engaging elements approaching from the tangential direction with the engaging recesses and sequentially disengage the engaging elements that have been engaged with the engaging recesses, thereby winding or unwinding the sheet curtain onto or from the winding roll, thereby moving the sheet curtain up and down; A sheet shutter in which a recess surrounded by a contact portion is formed on an engagement surface of the engaging element that contacts the engaging recess.

2. The sheet shutter according to claim 1 , wherein the recess is recessed in a stepped shape.

3. The sheet shutter as described in claim 1, further comprising a pair of guide rails extending in the vertical direction at both ends of the sheet curtain, supporting the engaging element so that it can move up and down, and having an opening formed therein that allows the recess formed in the engaging element to be viewed.

4. The sheet shutter according to claim 1 , wherein the recess forms a material mark indicating a resin material of the engaging element.

5. A sheet curtain wound on a winding roll; A plurality of resin engaging members are attached to both ends of the sheet curtain and arranged in a direction in which the sheet curtain is rolled up; a gear member that has a plurality of engaging recesses arranged in a circumferential direction and that rotates to sequentially engage the engaging elements approaching from a tangential direction with the engaging recesses and sequentially disengage the engaging elements that have been engaged with the engaging recesses, thereby winding or unwinding the sheet curtain onto or from the winding roll and moving the sheet curtain up and down; a metal contact block that is disposed on the opposite side of the gear member with the engaging element therebetween and that comes into contact with the engaging element engaged with the engaging recess when the engaging element moves radially outward of the gear member; A sheet shutter in which a recess surrounded by a contact portion is formed on a contact surface of the engaging element that comes into contact with the contact block.

6. The sheet shutter according to claim 5 , wherein the recess is recessed in a stepped shape.

7. The sheet shutter as described in claim 5, further comprising a pair of guide rails extending in the vertical direction at both ends of the sheet curtain, supporting the engaging element so that it can move up and down, and having an opening formed therein that allows the recess formed in the engaging element to be viewed.

8. The sheet shutter according to claim 5 , wherein the recess forms a material mark indicating a resin material of the engaging element.

Images