Structure to prevent the bottom of the tent fabric from getting caught in an accordion-type tent

Abstract

To prevent a hem of a tent fabric of a bellows tent from being rolled in casters or surrounding parts, etc. without being hung down regardless of a degree of spacing between gantry frames.SOLUTION: As a tent fabric hem roll-in prevention structure A attached to a bellows tent, a cantilevered plate spring 5 is fixed to be integrated with a column leg 3a, and the plate spring 5 is provided with required elasticity and a required length at least for a tip portion 5b to be able to push a slack hem 4a of a tent fabric 4 outward from a side wall 3b of an elastic tubular frame structure in either a non-elastic deformed state or in an elastically bowed state, depending on an interval between adjacent gate frames 3, 3.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a structure for preventing the bottom of a tent fabric from being caught in an accordion-type tent that has an expansion mechanism and is widely used in warehouses, workshops, etc. [Background technology]

[0002] Generally, accordion-type tents are also called expandable tent houses, and are widely used in warehouses, workshops such as painting workshops, hangars (garages), and the like. The basic structure of an accordion-type tent is a gate-shaped (also called an inverted U-shaped) frame that combines a pair of posts supporting the tent fabric on both side walls and a beam that connects the top ends of these posts to support the ceiling, creating expandable accordion-shaped side walls and ceiling.

[0003] The multiple portal frames are arranged in a row in the depth direction with their frontages aligned, the bases of the pillars of each portal frame are supported by casters so that they can be moved freely, and tent fabric is attached to the pillars and beams, allowing them to be moved as a unit.

[0004] In the accordion-type tent constructed in this manner, the length of the cylindrically extending tent house in the ridge direction can be changed like an accordion by moving each gate-shaped frame in the length direction of the row.

[0005] In addition, when the gap between each gate-shaped frame of an accordion-type tent is narrowed, the tent fabric bends like an accordion between each gate-shaped frame, and the pleated parts get into the gap between the gate-shaped frames as they gradually narrow, so the bottoms of the tent fabric covering both side walls of the tent house are easily caught between the wheels and the track surface of the casters that rotate below the column base.

[0006] To prevent the bottom of the tent fabric from getting caught in such a situation, a known method is to run a guide wire along the inner wall of the bottom of the tent fabric in advance, and use the tension to prevent the bottom from sagging and getting caught around the casters (Patent Document 1).

[0007] Also, as shown in Figure 6, there is known a structure B in which adjacent column bases 9 in the direction of movement of the portal frame are connected by rod-shaped materials 11 having hinges 10, and when the distance between the column bases 9 of each portal frame is reduced, the rod-shaped materials 11 are folded and the hinges 10 are caused to protrude so as to push the bottom of the tent fabric outward from the casters 12, thereby preventing the bottom from getting caught (Patent Document 2).

[0008] Furthermore, as shown in Figure 7, in a previous patent application, the inventors of the present application disclosed an anti-entanglement structure C in which, when the distance between adjacent portal (inverted U-shaped) frames 3 in the ridge direction narrows, a link arm 14 is provided in which the hinge 13 portion bends in a V-shape and protrudes outward from the caster 2, thereby stabilizing the posture of the base 6 and caster 2 while removing slack in the bottom hem 4a of the tent fabric (Patent Document 3). [Prior art documents] [Patent documents]

[0009] [Patent Document 1] Japanese Patent Application Publication No. 60-62380 [Patent Document 2] Japanese Patent Application Laid-Open No. 2013-133629 [Patent Document 3] Patent Publication No. 2021-67072 Summary of the Invention [Problem to be solved by the invention]

[0010] However, in the above-mentioned conventional accordion-type tent structures B and C, the extent to which the pleats at the bottom of the tent fabric are pushed outward from the rails at the hinge part is determined by the distance between adjacent portal (inverted U-shaped) frames in the ridge direction. Therefore, there are cases where the portal frames are positioned in a state where they cannot be pushed out sufficiently. For example, if the distance between the portal frames is not narrowed sufficiently while the portal frames are moving, the bottom of the tent fabric may be prone to getting caught in the tent.

[0011] Therefore, the object of this invention is to solve the above-mentioned problems and improve the structure for preventing the bottom of the tent fabric from getting caught in the accordion-type tent, so that the bottom of the tent fabric will always stay firm and will not sag, regardless of the width or narrowness of the spacing between the portal frames, and will not get caught in the casters or their surrounding areas. [Means for solving the problem]

[0012] In order to solve the above problems, the present invention provides a structure for preventing the bottom of a tent from getting caught in an accordion-type tent, which comprises an expandable cylindrical frame structure in which a plurality of portal frames each having a column base movably supported by casters are arranged in a row with the same width, and the length of the row can be changed by changing the interval between adjacent portal frames, and an accordion-foldable tent fabric covering at least the side wall surfaces of the expandable cylindrical frame structure, A cantilevered leaf spring is fixed integrally to the column base, and the leaf spring is of a length that allows it to push the loosened bottom of the tent fabric outward from the side wall surface of the expandable cylindrical frame structure when not elastically deformed, and the leaf spring has an elastic force that allows it to push out when elastically deformed in a bow shape, thereby creating a structure to prevent the bottom of the tent fabric from getting caught in the accordion-type tent.

[0013] The structure of the present invention for preventing the bottom of the tent fabric from getting caught in, configured as described above, has the base end of a plate spring fixed integrally to the column base of the portal frame, and this plate spring has the required elasticity and length, so that whether the spring is in a state where it is not elastically deformed or in a state where it is elastically deformed in a bow shape, its entire length and elastic force can push the accordion-folded bottom of the tent fabric from the inside to the outside of the side wall surface of the expandable cylindrical frame structure.

[0014] As a result, the tent fabric covering at least the side wall surfaces of the stretchable cylindrical frame structure of the accordion-type tent can push the bottom of the tent fabric from the inside to the outside of the side wall surfaces of the stretchable cylindrical frame structure, preventing it from getting caught in the casters and surrounding areas, even when the gap between adjacent gate-type frames narrows and the fabric is loose like folds, or when such looseness is slight.

[0015] Furthermore, when the leaf spring elastically deforms in a bow shape from the base end fixed to the column base of the portal frame to the tip end, it is difficult to make elastic contact with the tent fabric near the column base close to the base end. However, by providing a fulcrum near the column base that changes the deflection angle of the leaf spring, it becomes possible to make the leaf spring elastically deform in a bow shape along the side wall surface and press it against the tent fabric even near the column base close to the base end of the leaf spring. Therefore, even near the base of the column where the action of the plate spring is difficult to fully exert, the bottom of the loosened tent fabric can be pushed out from the inside to the outside of the side wall surface of the expandable cylindrical frame structure.

[0016] Furthermore, when an accordion-type tent is in use and the spacing between the portal frames frequently narrows and widens, at least the tip of the plate spring comes into contact with and rubs against the tent fabric, easily damaging the fabric in parts; however, by having the plate spring at least at its tip end have a curved guide surface that can smoothly slide against the tent fabric, the durability of the accordion-type tent can be increased without damaging the tent fabric.

[0017] The above-mentioned plate spring can be made of a single plate spring, but it may also be made of a combination of a plurality of plate-shaped elastic materials stacked together in the shape of a leaf spring, for example. The plate-shaped elastic material may be a long plate made of a single metal such as stainless steel that has spring-like elasticity, but it may also be a composite material made of a single or multiple types of well-known plate-shaped elastic material. [Effects of the Invention]

[0018] This invention provides a structure for preventing the bottom of the tent fabric from getting caught in an accordion-type tent, in which a plate-shaped spring is fixed to the base of a portal frame structure and has the elasticity and required length to push the loose bottom of the tent fabric outward from the portal frame structure when it is not elastically deformed and when it is elastically deformed in a bow shape.This has the advantage that, regardless of the width or narrowness of the spacing between the portal frames, the bottom of the tent fabric is always tight and does not get caught in the casters or surrounding areas. [Brief explanation of the drawings]

[0019] [Figure 1] 1 is a perspective view of a bellows-type tent equipped with a structure for preventing the bottom of the tent fabric from being caught in an embodiment; [Figure 2] FIG. 1 is an enlarged perspective view showing a main part of a tent fabric bottom entanglement prevention structure according to an embodiment; [Figure 3] Enlarged cross-sectional view of the III-III line in Figure 1, viewed from the direction of the arrow. [Figure 4] An enlarged cross-sectional view of the IV-IV line in Figure 1, viewed from the direction of the arrow. [Figure 5] Enlarged cross-sectional view of the VV line cross section of Figure 1, seen from the direction of the arrow. [Figure 6] An explanatory diagram of the main part of the tent fabric entrapment prevention structure shown in Patent Document 2 [Figure 7] An explanatory diagram of the main part of the tent fabric entrapment prevention structure shown in Patent Document 3 DETAILED DESCRIPTION OF THE INVENTION

[0020] An embodiment of the present invention will be described below with reference to the accompanying drawings. 1 to 5 is a structure A for preventing the hem of a tent fabric from getting caught in an accordion-type tent, in which the accordion-type tent 1 comprises a plurality of portal frames 3, each equipped with a column base 3a movably supported by casters 2, arranged in a row with the same width, which are connected by a well-known link mechanism as necessary, and which comprises an expandable cylindrical frame structure that can change the length of the row by changing the spacing between adjacent portal frames 3, 3. The side walls and ceiling of this expandable cylindrical frame structure are covered with accordion-foldable tent fabric 4, which is attached to each portal frame 3 with strings or the like.

[0021] As shown in FIG. 2, the tent fabric bottom entrapment prevention structure A attached to the accordion-type tent 1 has a base end 5a of a cantilevered plate spring 5 fixed integrally with a pedestal 3a. The plate spring 5 has the required elasticity and length so that at least the tip 5b can push the loosened bottom 4a of the tent fabric 4 outward from the side wall surface 3b of the elastic cylindrical frame structure, depending on the distance between adjacent gate-shaped frames 3, 3, whether in a non-elastically deformed state or in a bow-shaped elastically deformed state.

[0022] The gate-shaped frame 3 used in the basic structure of the accordion-type tent 1 (Fig. 1) has a pair of support posts, each consisting of a pair of pillars standing upright on a base 6 together with a plate-shaped beam 3c, arranged in pairs on the left and right across the width of the tent house's frontage, with the upper ends of these support posts connected by beams made of rod-shaped material such as arches, forming a gate-shaped (also called an inverted U-shaped) frame shape, and casters 2 (Fig. 2) are attached to the underside of the base 6 that supports the support posts.

[0023] A plurality of such portal frames 3 are arranged in a row with their frontages aligned, and rails 7 are laid along the row below each of the left and right column bases 3a. The expandable cylindrical frame structure configured in this manner allows the length of the cylindrically extending tent house ridge to be changed like an accordion by moving adjacent portal frames 3 on the rails 7 to change the spacing between them.

[0024] The illustrated plate spring 5 is formed into a hairpin shape by combining two long plate-shaped elastic materials having the required width, thickness, and length, and the tip portion 5b is formed with a guide surface consisting of an R-shaped curved surface that can slide smoothly against the tent fabric. Such a plate spring 5 has its base end fixed to a plate beam 3c, which is integral with a base 6 to which a pair of column bases 3a are fixed, by bolts and nuts or, if necessary, by welding, so that it acts as a cantilever spring, and the other free end can elastically deform in a bow shape within a horizontal plane or, if necessary, within an inclined plane.

[0025] Furthermore, a rod-shaped fulcrum 8 is provided upright on the base 6 so that the deflection angle of the plate spring 5 provided near the pedestal 3a is aligned with the side wall surface 3b (Figures 2 and 3), and the free end side of the plate spring 5 bends along the side wall surface 3b near the pedestal 3a close to the base end, elastically deforming in a bow shape against the inner wall surface of the bottom 4a of the tent fabric 4, so as to be in pressure contact with as wide an area as possible.

[0026] The leaf spring 5 can be made of a well-known material having the required spring elasticity, and the required elastic force and durability can be obtained by using a long plate-shaped metal material of an appropriate thickness made of stainless steel or other stainless steels, copper, iron, etc. Elastic materials other than metals, such as rubber, resin, and wood, can also be used, either singly or integrated as a composite material.

[0027] These long plate-shaped materials can be used alone when preparing them to achieve the required elasticity and length, or multiple sheets can be stacked to achieve the required elastic force. The long plate-shaped material can be folded at the center or end into a hairpin shape with a rounded tip (R), and multiple elastic materials can be combined to form the shape shown in the figure. Other types of plate springs (not shown) can also be used, formed using long plate-shaped materials into other well-known spring shapes, such as a torsion coil type.

[0028] The plate spring 5 is formed using a long plate material whose thickness and length are adjusted according to the size of the accordion-type tent so that, whether in a state where it is not elastically deformed or in a state where it is elastically deformed in a bow shape, at least the free end side including the tip portion 5b has the required elasticity and required length to push the loosened bottom portion 4a of the tent fabric 4 into or outward from the side wall surface of the elastic cylindrical frame structure.

[0029] The plate spring 5 shown in Figure 3-5 shows a form corresponding to the case where the pitch width of the bellows of a bellows tent is, for example, about 150 cm.The plate is made of rolled steel for springs (for example, a spring steel strip with a thickness of about 0.5 to 1.0 mm) and has a long plate material with a rounded tip folded over, so that the plate has a width of about 8 cm and a length of about 50 cm.The plate is made of rolled steel for springs (for example, a spring steel strip with a thickness of about 0.5 to 1.0 mm) and has a long plate material with a rounded tip folded over, which is joined together to form a two-layer shape with a rounded tip (R) as shown.

[0030] The total length of the plate spring 5 of this type in a state without elastic deformation is long enough to push the loosened bottom 4a of the tent fabric 4 from the inside to the outside of the side wall surface 3b of the elastic cylindrical frame structure, and the rounded tip 5b at the tip acts effectively as a guide surface. The guide surface of the curved tip portion 5b can be provided so as to cover not only the tip portion of the leaf spring, but also a required portion of the main body portion or the entire leaf spring.

[0031] The material of the tip portion 5b may be the same as that of the main body of the plate spring 5, or it may be formed separately from another material and attached to the tip portion 5b. For example, it may be a cap made of synthetic resin or the like, or it may be made of a material that forms a smooth surface by gluing, welding, or fitting together parts with gently curved surfaces to form a single piece that covers the required part.

[0032] As shown in Figures 3 and 4, when the distance between adjacent portal frames 3 is narrowed, the bottom 4a of the tent fabric 4 gradually loosens like pleats and tends to slip inward from the side wall surface 3b of the expandable cylindrical frame structure. However, since the elastic force of the plate spring 5 is always exerted on the bottom 4a of the tent fabric toward the outside of the side wall surface 3b of the expandable cylindrical frame structure, the bottom can always be pushed out regardless of the degree of loosening.

[0033] Furthermore, as shown in Figure 5, when the spacing between adjacent portal frames 3 narrows and the portal frames 3 come close enough to touch each other, the plate springs 5 ​​assume a position perpendicular to the side wall surfaces 3b and are no longer able to exert their elastic force on the tent fabric 4, but their overall length allows them to push the loosened bottom hem 4a of the tent fabric 4 outward from the side wall surfaces 3b of the elastic cylindrical frame structure.

[0034] Furthermore, the central portion of the leaf spring 5, from the base end 5a fixed to the column base 3a to the tip end 5b, is most susceptible to elastic deformation in a bow shape, while the portion closer to the base end 5a has a smaller amount of elastic deformation.

[0035] However, as shown in Figure 3, the angle of deflection of the plate spring 5 changes along the rod-shaped fulcrum 8, so that sufficient elastic force can be applied to the tent fabric 4 even in the area close to the base end 5a where the pushing action of the plate spring 5 is difficult to reach, and regardless of the width or narrowness of the spacing between the portal frames. Therefore, the entire length of the slackened bottom portion 4a of the tent fabric 4 can be pushed out from the inside to the outside of the side wall surface 3b of the stretchable cylindrical frame structure.

[0036] In this way, almost the entire bottom 4a of the tent fabric 4 can be pushed out from the inside to the outside of the side wall surface 3b of the stretchable cylindrical frame structure, so that it does not get caught in the casters 2 or their surrounding parts, regardless of the width or narrowness of the spacing between the gate-shaped frames. [Explanation of symbols]

[0037] 1. Accordion tent 2, 12 casters 3 Gate-type frame 3a, 9 column base 3b Side wall surface 3c Plate beam 4 Tent fabric 4a Hem 5. Leaf spring 5a Proximal end 5b Tip 6 Base 7 Rail 8 fulcrum 10, 13 Hinge 11 Bar material 14 Link arm A, B, C Tent bottom entanglement prevention structure

Claims

1. A tent fabric bottom entrapment prevention structure provided for an accordion-type tent, comprising: a stretchable cylindrical frame structure in which a plurality of portal frames each having a column base movably supported by casters are arranged in a row with the same width, and the length of the row can be changed by changing the interval between adjacent portal frames; and a accordion-foldable tent fabric covering at least the side wall surfaces of the stretchable cylindrical frame structure, A cantilevered leaf spring is fixed integrally to the column base, and the leaf spring is of a length that allows it to push the loosened bottom of the tent fabric outward from the side wall surface of the expandable cylindrical frame structure when it is not elastically deformed, and the leaf spring has an elastic force that allows it to push out the loosened bottom of the tent fabric when it is elastically deformed in a bow shape, thereby preventing the bottom of the tent fabric from getting caught in the accordion-type tent.

2. 2. The structure for preventing the bottom of the tent fabric from getting caught in an accordion-type tent as described in claim 1, wherein a fulcrum for changing the deflection angle of the plate spring is provided near the base of the column so that the plate spring elastically deforms in a bow shape along the side wall surface.

3. 3. The structure for preventing the bottom of a tent fabric from being caught in an accordion-type tent according to claim 1 or 2, wherein the leaf spring has a curved guide surface at least at the tip thereof that can smoothly slide against the tent fabric.

4. 3. The structure for preventing the bottom of a tent fabric from being caught in an accordion-type tent according to claim 2, wherein the plate spring is a plate spring formed by combining a plurality of plate-shaped elastic materials.

5. 4. The structure for preventing the bottom of a tent fabric from being caught in an accordion-type tent according to claim 3, wherein the plate spring is a plate spring formed by combining a plurality of plate-shaped elastic materials.

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