Sheet shutter

Abstract

To provide a sheet shutter configured in such a manner of suppressing deformation of a guide rail when a sheet curtain is inflated by wind pressure, compared with a case where a guide rail is freely deformable, and of suppressing damage to the guide rail, compared with a case where metal reinforcing plates are provided for sandwiching the guide rai therebetween.SOLUTION: A sheet shutter includes: a sheet curtain that opens or closes an opening section by moving up or down; multiple engaging elements attached to both widthwise ends of the sheet curtain and arranged in a row in the vertical direction; a pair of guide rails that sandwich the sheet curtain in the widthwise direction and extend in the vertical direction, with engaged portions formed to engage with the engaging elements so that they can move in the vertical direction; elastic members made of an elastic material that are arranged to sandwich the guide rail from the thickness direction of the sheet curtain; and reinforcing members that are arranged to sandwich the guide rail from the thickness direction via the elastic members.SELECTED DRAWING: Figure 11

Description

[Technical Field]

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

[0002] Patent document 1 describes a guide rail for engaging and retaining locking bodies arranged on both sides of a sheet-like shutter curtain in a non-slip manner, and for guiding the opening and closing of the opening by the shutter curtain, the guide rail being composed of a support rail fixed to the main body and having a deep groove-shaped concave groove portion that opens on the inner side of the opening width, and a rigid rail body that can be freely fitted into the concave groove portion via a resilient mechanism and has a locking piece at its tip that prevents the locking body from falling out, and the rail body is a split type in which at least one of the locking pieces is displaceable, and when fitted within the concave groove portion it maintains a guiding position that prevents the locking body from falling out, but when it protrudes from the concave groove portion the displaceable locking piece is displaced to assume a release position to release the locking body. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2001-207756 Summary of the Invention

[0004] Conventionally, sheet shutters have been provided with multiple resin engaging elements at both ends of the sheet curtain. These engaging elements are adapted to engage with engaging portions formed on guide rails extending in the vertical direction. Specifically, a pair of guide rails are provided that extend in the vertical direction across the width of the sheet curtain, sandwiching the sheet curtain. These guide rails are made of resin, and the guide rails are formed with engaging portions into which the engaging elements provided at both ends of the sheet curtain fit. The sheet curtain moves up and down with the engaging elements provided on the sheet curtain engaged with the engaging portions of the guide rails.

[0005] Here, when wind pressure is applied to the sheet curtain while the sheet curtain is closing an opening or the like, movement of both ends of the sheet curtain is restricted, causing the sheet curtain to bulge in a curved shape.

[0006] Here, if the guide rail is deformable, when the sheet curtain expands due to wind pressure, the guide rail will be deformed, and the engagement between the engaging element on the sheet curtain and the engaged portion of the guide rail will be released.

[0007] On the other hand, if a metal reinforcing plate is provided that directly sandwiches the resin guide rail to suppress deformation of the guide rail, when the sheet curtain expands due to wind pressure, deformation of the guide rail is suppressed, but the guide rail may be damaged.

[0008] The object of the present disclosure is to suppress deformation of the guide rail when the sheet curtain is inflated by wind pressure, compared to when the guide rail is freely deformable, and to suppress damage to the guide rail, compared to when a metal reinforcing plate is arranged to directly sandwich the guide rail. [Means for solving the problem]

[0009] The sheet shutter according to the first aspect of the present disclosure is characterized by comprising a sheet curtain that moves up and down, a plurality of engaging elements attached to both widthwise ends of the sheet curtain and arranged in a row in the vertical direction, a pair of resin guide rails that sandwich the sheet curtain in the widthwise direction and extend in the vertical direction, with engaging portions formed to engage with the engaging elements so that the engaging elements can move in the vertical direction, an elastic member made of an elastic material that is arranged to sandwich the guide rail from the thickness direction of the sheet curtain, and a reinforcing member made of a metal material that is arranged to sandwich the guide rail from the thickness direction via the elastic member.

[0010] According to the above configuration, the reinforcing member made of metal sandwiches the resin guide rail via the elastic member, which suppresses deformation of the guide rail when the sheet curtain is inflated by wind pressure compared to when the guide rail is free to deform, and suppresses damage to the guide rail compared to when the metal reinforcing plate is provided so as to directly sandwich the guide rail.

[0011] 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 elastic member is formed from a rubber material which is the elastic material.

[0012] According to the above configuration, the elastic member is made of a rubber material, which makes it possible to suppress a decrease in workability when attaching the elastic member compared to when a coil spring is used as the elastic member.

[0013] A sheet shutter according to a third aspect of the present disclosure is a sheet shutter according to the first or second aspect, characterized in that it is provided with a gear member that is arranged at the upper end portion of the sheet curtain, has a plurality of engaging recesses arranged circumferentially to engage with the engaging elements, and rotates to sequentially engage the engaging elements with the engaging recesses and move the sheet curtain up and down, and the elastic member and the reinforcing member are provided only at the lower end portion of the guide rail.

[0014] According to the above configuration, when wind pressure is applied to the sheet curtain, the movement of both ends of the sheet curtain is restricted, causing the sheet curtain to bulge in a curved shape. Specifically, since the lower end of the sheet curtain is a free end, the amount of bulging of the lower end of the sheet curtain is greater than the amount of bulging of the upper end of the sheet curtain.

[0015] Here, the elastic member and the reinforcing member are provided only at the lower end portion of the guide rail, which effectively suppresses deformation of the guide rail and damage to the guide rail compared to when the elastic member and the reinforcing member are provided only at the upper end portion of the guide rail.

[0016] A sheet shutter according to a fourth aspect of the present disclosure is characterized in that, in the sheet shutter described in any one of the first to third aspects, the engaged portion is concave and opens on the inside in the width direction while the engaging element is inserted therein, and a pair of flange portions protruding in opposite directions are formed at the open end of the engaged portion that is concave on the guide rail.

[0017] According to the above configuration, a pair of flanges are formed at the open end of the guide rail so as to protrude in opposing directions, thereby preventing the engaging element engaged with the engaged portion from slipping out of the engaged portion.

[0018] A sheet shutter according to a fifth aspect of the present disclosure is the sheet shutter according to the fourth aspect, wherein the pair of flange portions protrude inward in the width direction from the elastic member.

[0019] According to the above configuration, the flange portion of the guide rail protrudes inward in the width direction relative to the elastic member. Therefore, when a relatively strong wind pressure is applied to the sheet curtain, the flange portion mainly deforms, causing the engaging element to come out of the engaged portion of the guide rail. This prevents damage to the guide rail. [Effects of the Invention]

[0020] According to the present disclosure, when a sheet curtain inflates due to wind pressure, deformation of the guide rail can be suppressed compared to when the guide rail is freely deformed, and damage to the guide rail can be suppressed compared to when a metal reinforcing plate is arranged to directly sandwich the guide rail. [Brief explanation of the drawings]

[0021] [Figure 1] FIG. 1 is a perspective view showing a sheet shutter according to an embodiment of the present disclosure. [Figure 2] FIG. 2 is a perspective view showing the upper end portion of the sheet shutter according to the embodiment of the present disclosure. [Figure 3] 1 is a perspective view showing a guide rail, a side frame, etc. provided in a sheet shutter according to an embodiment of the present disclosure. FIG. [Figure 4] 1 is an enlarged perspective view showing a curtain unit and an engagement element provided in a sheet shutter according to an embodiment of the present disclosure. FIG. [Figure 5] 1 is a perspective view showing a curtain unit and an engagement element provided in a sheet shutter according to an embodiment of the present disclosure. FIG. [Figure 6] 1A and 1B are a plan view and a side view showing an engagement element provided in a sheet shutter according to an embodiment of the present disclosure. [Figure 7] 1 is an exploded perspective view showing a curtain unit provided in a sheet shutter according to an embodiment of the present disclosure. FIG. [Figure 8] 11 is an enlarged side view of a portion G01 in FIG. 10 showing engagement between an engagement element and an engagement recess in the sheet shutter according to the embodiment of the present disclosure. FIG. [Figure 9] FIG. 2 is an exploded perspective view showing a gear member, a contact block, a curtain unit, etc. of a sheet shutter according to an embodiment of the present disclosure. [Figure 10] 1 is a side view showing a gear member, a contact block, a curtain unit, etc. of a sheet shutter according to an embodiment of the present disclosure. FIG. [Figure 11] 1 is a cross-sectional view showing a guide unit and the like provided in a sheet shutter according to an embodiment of the present disclosure. [Figure 12] FIG. 10 is a cross-sectional view showing a guide unit provided in a sheet shutter according to a comparative example to the embodiment of the present disclosure. [Figure 13] FIG. 10 is a cross-sectional view showing a guide unit provided in a sheet shutter according to a comparative example to the embodiment of the present disclosure. [Figure 14] 1A and 1B are state diagrams showing a state in which no wind pressure is applied to the sheet curtain and a state in which wind pressure is applied to the sheet curtain in a sheet shutter according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0022] An example of a sheet shutter according to an embodiment of the present disclosure will be described with reference to Figures 1 to 14. Note that arrow H shown in the figures indicates the up-down direction (vertical direction) of the sheet shutter, arrow W is perpendicular to arrow H and indicates the width direction (horizontal direction) of the sheet shutter, and arrow L is perpendicular to arrows H and W and indicates the depth direction (horizontal direction) of the sheet shutter.

[0023] (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, it comprises a frame 12, a guide unit 14, a take-up roll 20, a curtain unit 30, a drive roll 60, and a contact block 80. The frame 12, the guide unit 14, the take-up roll 20, the curtain unit 30, the drive roll 60, and the contact block 80 are symmetrical in the width direction with respect to a center line CL11 of the sheet shutter 10. The entrance is an example of an opening.

[0024] [Frame 12] 1, the frame 12 includes a pair of side frames 22 and a shutter case 18. The pair of side frames 22 extend vertically and are arranged on both sides of the delivery entrance in the width direction, at both ends of the curtain unit 30 in the width direction.

[0025] 2, the cross section of the side frame 22 is C-shaped with the inside in the width direction open. In this embodiment, the inside in the width direction is the side facing the center part of the width direction of the sheet shutter 10, and the outside in the width direction is the side opposite to the side facing the center part of the width direction of the sheet shutter 10. Furthermore, a guide unit 14 extending in the vertical direction is attached to each of the pair of side frames 22.

[0026] The shutter case 18 extends in the width direction at the upper ends of the pair of side frames 22 and spans the pair of side frames 22. The cross section of the shutter case 18 is rectangular and extends in the depth direction.

[0027] [Winding roll 20] As shown in FIG. 2, the winding roll 20 is disposed inside the shutter case 18 on one side in the depth direction (the right side in the figure), and an end of the curtain unit 30 is attached to the winding roll 20.

[0028] The winding roll 20 extends in the width direction, and the axial direction of the winding roll 20 is the 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").

[0029] In this configuration, a force acts on the curtain unit 30 in the direction in which it is wound by the winding roll 20 .

[0030] [Curtain Unit 30] When the curtain unit 30 closes the entrance of a warehouse or the like, the curtain unit 30 is disposed between a pair of side frames 22 as shown in Fig. 1. The curtain unit 30 separates the interior area of ​​the warehouse or the like from the exterior area of ​​the warehouse or the like.

[0031] 3 and 4, the curtain unit 30 includes a sheet curtain 32 and a pair of wires 36 provided at both widthwise end portions of the sheet curtain 32. The curtain unit 30 further includes a plurality of engaging elements 40 attached to both widthwise end portions of the sheet curtain 32 and arranged side by side in the vertical direction (the movement direction of the curtain unit 30), and screws 38 for attaching the engaging elements 40 to the sheet curtain 32.

[0032] -32 sheet curtains, 36 wires- The sheet curtain 32 is formed in a sheet shape from a resin material, and has a rectangular shape extending in the vertical direction (movement direction) when viewed from the depth direction, as shown in Fig. 1. In other words, the thickness direction of the sheet curtain 32 is the depth direction. The end of the sheet curtain 32 in the movement direction is attached to the winding roll 20, as shown in Fig. 2.

[0033] 4 and 5, both ends of the sheet curtain 32 in the 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.

[0034] The wire 36 is disposed in the hollow portion 32a and extends in the direction of movement of the sheet curtain 32, and is provided at both ends in the 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 way, by disposing the wire 36 in the hollow portion 32a, both ends in the width direction of the sheet curtain 32 bulge in the thickness direction of the sheet curtain 32 compared to other portions.

[0035] - Engagement element 40, screw 38 - The engaging elements 40 are attached to both end portions in the width direction of the sheet curtain 32, and as shown in Figures 4 and 5, 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. The engaging elements 40 are integrally formed using a resin material (in this embodiment, polyacetal (POM)).

[0036] As shown in Figure 6(A), when viewed from above, the engaging element 40 has a rectangular shape with a U-shaped groove 42 that opens on the inner side in the width direction, and protrusions 44 are formed at the opening ends of the groove 42.

[0037] Furthermore, a gradually changing portion 42a is formed on the inner side of the width of the groove 42, where the opening width gradually widens toward the inside in the width direction when viewed from above. Also, an elliptical circular portion 42b with a wider width is formed on the outer side of the width of the groove 42, when viewed from above. Both widthwise ends of the sheet curtain 32, which is expanded by the wire 36 (see FIG. 4), are arranged in this circular portion 42b.

[0038] Furthermore, the engaging element 40 is formed with a side surface 40a facing outward in the 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. The outer portion of this through-hole 46 in the width direction is formed with an expanding diameter portion 46a whose diameter dimension gradually increases toward the outside in the width direction.

[0039] As shown in Figures 4 and 7, a screw 38 is inserted into this through hole 46 from the outside in the width direction, and the tip portion of the screw 38 is screwed into the wire 36, thereby attaching the engaging element 40 to both ends of the sheet curtain 32 in the width direction.

[0040] The screw 38 is a countersunk tapping screw, and when the tip portion of the screw 38 is screwed into the wire 36, the head of the screw 38 is positioned in the expanded diameter portion 46a of the through hole 46, as shown in Figures 4 and 7. This allows the head of the screw 38 to fit into the expanded diameter portion 46a of the through hole 46 and not protrude from the side surface 40a of the engaging element 40.

[0041] Furthermore, as shown in Figures 6(B) and 8, the engaging element 40 is formed with a contact portion 50 that contacts the contact block 80 and an engaging portion 54 that engages with an engaging recess 66 of a gear member 64 provided on the drive roll 60.

[0042] [Drive roll 60] 2, the drive roll 60 is disposed inside the shutter case 18 on the other side in the depth direction (the left side in the figure) and above the pair of side frames 22. In addition, a portion 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.

[0043] The drive roll 60 extends in the width direction, with the axial direction of the drive roll 60 being the width direction. The drive roll 60 is rotatably supported by a frame member (not shown). The drive roll 60 includes a roll body 62 extending in the width direction and a pair of gear members 64 attached to both ends of the roll body 62 in the width direction.

[0044] 9, the gear member 64 is made of metal and has an annular shape, and a plurality of engaging recesses 66 that engage with the engaging portions 54 of the engaging pieces 40 are formed side by side in the circumferential direction on the outer peripheral surface of the gear member 64. In addition, a flange 78 that protrudes radially outward relative to other portions is formed on the outer side of the gear member 64 in the width direction.

[0045] 8, the engagement recess 66 has a pair of side flat surfaces 66a formed on both end portions in the gear circumferential direction, and a bottom surface 66b sandwiched between the pair of side flat surfaces 66a and facing outward in the radial direction of the gear member 64 (hereinafter referred to as the "gear radial direction"). The side flat surfaces 66a are flat, and the bottom surface 66b is curved and convex inward in the gear radial direction.

[0046] Furthermore, the driving roll 60 is rotated in both positive and negative directions by the driving force transmitted from a motor (not shown).

[0047] [Contact block 80] The contact blocks 80 are made of metal and are arranged at the other depth side and both widthwise end sides inside the shutter case 18, as shown in Fig. 2. Specifically, the contact blocks 80 are arranged on the opposite side of the gear member 64 with the engaging element 40 sandwiched therebetween, as shown in Fig. 10.

[0048] 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.

[0049] 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.

[0050] [Guide unit 14] 11, the guide unit 14 is disposed inside the side frame 22 and attached to the side frame 22. An engaging element 40 attached to the sheet curtain 32 engages with an engaged portion 100a formed on a guide rail 100 provided on the guide unit 14 so as to be movable in the up and down direction. Details of the guide unit 14 will be described later.

[0051] (Effect of overall structure) When the entrance of a warehouse or the like is blocked by the curtain unit 30, and the drive roll 60 shown in FIG. 10 receives rotational force from the motor and rotates in the forward direction (the direction K01 shown in FIG. 10), the rotating gear member 64 sequentially engages the engaging elements 40 that approach in 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).

[0052] Then, the portion of curtain unit 30 that is blocking the entrance moves upward while being guided by a pair of guide rails 100 shown in Figure 11. This causes the entrance of the warehouse or the like to be opened by curtain unit 30.

[0053] 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 10 rotates in the negative direction (K02 direction shown in Figure 10) as rotational force is transmitted from the motor, 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 unwind from the winding roll 20 (see Figure 2).

[0054] 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. As a result, the delivery entrance of the warehouse or the like is blocked by the curtain unit 30.

[0055] (Main part configuration) Next, the guide unit 14 will be described. As shown in Fig. 11, the guide unit 14 is disposed inside the side frame 22 and attached to the side frame 22. The guide unit 14 includes a guide rail 100, a pair of elastic members 120, a reinforcing plate 130, a retainer 140, and a mounting bolt 150.

[0056] [Guide Rail 100] The guide rail 100 is made of high-density polyethylene (HDPE), a resin material, and extends in the vertical direction. As shown in FIG. 11 , the guide rail 100 is formed with a recessed engaged portion 100a that is open on the inside in the width direction. Furthermore, a pair of flanges 102 are formed at the open end of the engaged portion 100a, protruding in opposing directions to prevent the engaging element 40 engaged with the engaged portion 100a from slipping out of the engaged portion 100a. Furthermore, the guide rail 100 is formed with a pair of outer surfaces 104 that face one side or the other in the depth direction.

[0057] Meanwhile, on the outer side of the guide rail 100 in the width direction, a pair of recesses 106 into which both ends of a retainer 140 having a C-shaped cross section fit, and a storage recess 108 into which the head of a mounting bolt 150 is stored. The guide rail 100 is disposed in the entire range in the vertical direction where the side frames 22 are provided.

[0058] [Elastic member 120] The elastic members 120 are formed using a rubber material, which is an elastic material, and as shown in Figure 11, a pair of elastic members 120 are provided to sandwich the guide rail 100 from the depth direction, and the cross section of the elastic members 120 is rectangular and extends in the width direction.

[0059] Specifically, the elastic member 120 is in surface contact with the outer surface 104 of the guide rail 100. Furthermore, the flange portion 102 of the guide rail 100 protrudes inward in the width direction from the inner end portion of the elastic member 120 in the width direction. Furthermore, the outer end portion of the elastic member 120 in the width direction is located outward in the width direction from the outer end portion (bottom portion) of the engaged portion 100a in the width direction. The elastic member 120 is arranged over the entire area in the up-down direction where the guide rail 100 is provided.

[0060] [Reinforcing plate 130] The reinforcing plate 130 is formed by bending a metal sheet, and extends in the vertical direction. Furthermore, as shown in Fig. 11, the cross section of the reinforcing plate 130 is U-shaped with the inside in the width direction open, and the reinforcing plate 130 sandwiches the guide rail 100 from the depth direction via the elastic member 120. The reinforcing plate 130 is arranged over the entire area in the vertical direction where the guide rail 100 is provided.

[0061] [Retainer 140] The retainer 140 is formed by bending a sheet metal member and extends in the vertical direction. Furthermore, as shown in Fig. 11, the cross section of the retainer 140 is C-shaped with the inside in the width direction open, and as described above, both ends of the retainer 140 fit into the recesses 106 formed in the guide rail 100. The retainer 140 is disposed in the vertical direction over the entire range in which the guide rail 100 is provided.

[0062] [Mounting bolt 150] 11 , the head of the mounting bolt 150 is disposed in a storage recess 108 formed in the guide rail 100, and the threaded portion of the mounting bolt 150 is inserted into through-holes (not shown) formed in the retainer 140, the reinforcing plate 130, and the side frame 22, and is tightened into the weld nut 28 attached to the side frame 22.

[0063] (Function of main components) Next, the operation of the guide unit 14 when wind pressure is applied to the sheet curtain 32 while the curtain unit 30 (sheet curtain 32) is blocking the loading entrance of a warehouse or the like will be described in comparison with the guide units 214, 314 of the sheet shutters 210, 310 according to comparative embodiments. First, the guide unit 214 of the sheet shutter 210 according to the comparative embodiment and the guide unit 314 of the sheet shutter 310 according to the comparative embodiment will be described, focusing on the differences from the guide unit 14 of this embodiment.

[0064] [Guide unit 214] 12, the guide unit 214 does not include an elastic member 120 or a reinforcing plate 130. Therefore, the guide rail 100 of the guide unit 214 is more easily deformed than the guide rail 100 of the guide unit 14. In this manner, the guide rail 100 of the guide unit 214 is deformable. Here, in this embodiment, being deformable means that the deformation of the portion of the guide rail 100 that sandwiches the engaged portion 100a from the depth direction is not restricted by other members.

[0065] [Guide unit 314] 13, the guide unit 314 does not include an elastic member 120. Furthermore, a tip end 330a of a reinforcing plate 330 included in the guide unit 314 contacts the inner portion of the outer surface 104 of the guide rail 100 in the width direction, and the reinforcing plate 330 directly sandwiches the guide rail 100 from the depth direction without an elastic member therebetween.

[0066] [Effect when wind pressure is applied] Next, when wind pressure is applied to the sheet curtain 32 while the curtain unit 30 is blocking the loading entrance of a warehouse or the like, movement of both ends of the sheet curtain 32 in the depth direction is restricted, causing the sheet curtain 32 to expand in a curved shape, as shown by the two-dot chain line in Figure 1. Here, the movement of the upper end of the sheet curtain 32 is restricted by gear member 64 (see Figure 2), and the lower end of the sheet curtain 32 is a free end, so the amount of expansion of the lower end portion of the sheet curtain 32 is greater than the amount of expansion of the upper end portion of the sheet curtain 32.

[0067] As shown in Figures 14(A) and (B), as the sheet curtain 32 expands, a force is applied to the engaging elements 40 attached to both ends of the sheet curtain 32 shown in Figure 11 to move inward in the width direction, causing the engaging elements 40 to try to come out of the engaging portions 100a formed on the guide rail 100.

[0068] Here, a normal level of wind pressure may be applied to the sheet curtain 32, causing the sheet curtain 32 to inflate. In this case, the guide unit 214 according to the comparative embodiment shown in Fig. 12 does not include the elastic member 120 and the reinforcing plate 130, and therefore the guide rail 100 is significantly deformed as shown by the two-dot chain line in Fig. 12. This causes the engaging element 40 to come out of the engaged portion 100a of the guide rail 100.

[0069] 11, the reinforcing plates 130 sandwich the guide rail 100 via the elastic members 120, preventing the guide rail 100 from deforming significantly. This prevents the engaging elements 40 from slipping out of the engaged portions 100a of the guide rail 100.

[0070] In contrast, a relatively strong wind pressure may be applied to the sheet curtain 32, causing the sheet curtain 32 to bulge. In this case, in the guide unit 314 according to the comparative embodiment shown in Fig. 13, the reinforcing plate 330 directly clamps the guide rail 100 without an elastic member in between, so the guide rail 100 is hardly deformed. As a result, the force of the engaging elements 40 trying to come out of the engaged portions 100a of the guide rail 100 will damage the guide rail 100.

[0071] On the other hand, in the guide unit 14 according to this embodiment shown in FIG. 11 , the reinforcing plate 130 sandwiches the guide rail 100 via the elastic member 120, causing the guide rail 100 to deform slightly. This causes the engaging element 40 to come out of the engaged portion 100a of the guide rail 100. In particular, because the flange portion 102 of the guide rail 100 protrudes inward in the width direction from the elastic member 120, the flange portion 102 of the guide rail 100 is primarily deformed, as shown by the two-dot chain line in FIG. 11 . This causes the engaging element 40 to come out of the engaged portion 100a of the guide rail 100. In other words, damage to the guide rail 100 is suppressed.

[0072] (summary) As explained above, in the sheet shutter 10, when a normal level of wind pressure is applied to the sheet curtain 32, deformation of the guide rail 100 is suppressed compared to the guide unit 214 of the sheet shutter 210 according to the comparative embodiment, and therefore the engaging element 40 is prevented from coming out of the engaged portion 100a of the guide rail 100. In other words, the sheet shutter 10 has higher wind pressure resistance performance compared to the sheet shutter 210.

[0073] On the other hand, when a relatively strong wind pressure is applied to the sheet curtain 32, the guide rail 100 is deformed and the engaging elements 40 come out of the engaged portions 100a of the guide rail 100, which reduces damage to the guide rail 100, compared to the guide unit 314 of the sheet shutter 310 according to the comparative embodiment. In other words, the sheet shutter 10 has an emergency return performance compared to the sheet shutter 310.

[0074] In other words, in the sheet shutter 10, deformation of the guide rail 100 is suppressed compared to the sheet shutter 210 in which the guide rail 100 is freely deformed, and damage to the guide rail 100 is suppressed compared to the sheet shutter 310 in which the metal reinforcing plate 330 is arranged to directly sandwich the guide rail 100.

[0075] Furthermore, in the sheet shutter 10, the elastic member 120 is made of a rubber material. Therefore, compared to when a coil spring is used as the elastic member, it is possible to suppress a decrease in workability when attaching the elastic member 120.

[0076] Furthermore, in the sheet shutter 10, the flange portion 102 of the guide rail 100 protrudes inward in the width direction from the inner end portion in the width direction of the elastic member 120. Therefore, when a relatively strong wind pressure is applied to the sheet curtain 32, the flange portion 102 of the guide rail 100 is mainly deformed, and the engaging element 40 comes out of the engaged portion 100a of the guide rail 100, compared to when the flange portion is sandwiched between reinforcing plates via the elastic member, and this makes it possible to suppress damage to the guide rail 100.

[0077] Furthermore, in the sheet shutter 10, the outer end in the width direction of the elastic member 120 is located on the outer side in the width direction relative to the outer end (bottom) in the width direction of the engaged portion 100a. Therefore, deformation of the guide rail 100 in the portion where the engaged portion 100a is formed can be suppressed compared to when the outer end in the width direction of the elastic member is located on the inner side in the width direction relative to the outer end in the width direction of the engaged portion.

[0078] Although the present disclosure has been described in detail with respect to a specific embodiment, it will be apparent to those skilled in the art that the present disclosure is not limited to such an embodiment and that various other embodiments are possible within the scope of the present disclosure. For example, in the above embodiment, the elastic member 120 and the reinforcing plate 130 are disposed over the entire area in which the guide rail 100 is provided in the vertical direction, but multiple elastic members 120 and reinforcing plates 130 may be provided at intervals in the vertical direction.

[0079] Furthermore, although not specifically described in the above embodiment, the elastic member 120 and the reinforcing plate 130 may be provided only at the lower end portion of the guide rail 100. This makes it possible to more effectively suppress deformation of the guide rail 100 and to more effectively suppress damage to the guide rail 100 than when the elastic member and the reinforcing plate are provided only at the upper end portion of the guide rail 100. Here, the lower end portion of the guide rail 100 refers to the portion below the center of the guide rail 100 in the up-down direction.

[0080] Although not specifically described in the above embodiment, the guide rail 100, the elastic member 120, and the reinforcing plate 130 may be divided into a plurality of pieces in the vertical direction.

[0081] Although not specifically described in the above embodiment, the sheet curtain 32 may receive wind pressure from either one side of the sheet curtain 32 or the other side. [Explanation of symbols]

[0082] 10 Sheet shutter 32 Sheet Curtain 40 Engagement element 64 Gear parts 66 Engagement recess 100 guide rail 100a Engaged part 102 flange 120 Elastic member 130 Reinforcing plate (an example of a reinforcing member)

Claims

1. A sheet curtain that opens or closes the opening by moving up and down; A plurality of engaging elements are attached to both ends of the sheet curtain in the width direction and are arranged in the vertical direction; a pair of guide rails that sandwich the sheet curtain in the width direction and extend in the vertical direction, the guide rails having engaged portions with which the engaging elements are engaged so as to be movable in the vertical direction; An elastic member made of an elastic material, provided to sandwich the guide rail from the thickness direction of the sheet curtain; a reinforcing member provided to sandwich the guide rail from the thickness direction via the elastic member; A sheet shutter equipped with:

2. The elastic member is formed of a rubber material, which is the elastic material. The sheet shutter according to claim 1.

3. A gear member is provided at the upper end portion of the sheet curtain, and has a plurality of engagement recesses arranged in a circumferential direction to engage with the engagement pieces, and rotates to sequentially engage the engagement pieces with the engagement recesses, thereby moving the sheet curtain up and down. The elastic member and the reinforcing member are provided only at the lower end portion of the guide rail. The sheet shutter according to claim 1.

4. The engaging portion is recessed so that the engaging element is inserted therein and the inner side in the width direction is open, A pair of flanges protruding in opposing directions are formed at an open end of the recessed engaged portion of the guide rail. The sheet shutter according to claim 1.

5. The pair of flange portions protrude inward in the width direction from the elastic member. The sheet shutter according to claim 4.

Images