Telescopic bracket for scaffolding construction

Abstract

To provide an extendable bracket for use in constructing scaffolding at construction sites, etc.SOLUTION: Provided is an extendable bracket for scaffolding construction in which an extendable tube that can be extended and contracted in an axial direction is constructed by slidably inserting an inner tube into an outer tube. The extendable bracket includes a guide mechanism that guides the mutual sliding movement of the outer tube and the inner tube in the axial direction while preventing the inner tube from rotating in a circumferential direction, and a locking mechanism that releasably locks and secures the inner tube so that it cannot slide. The locking mechanism (21) is configured by locking and securing bolt means (29) that is screwed through the outer tube (3) so as to be freely advanced and retractable to an outer surface of the inner tube (4), The guide mechanism (20) includes a slit (22) formed in the outer tube (3) and extending in the axial direction, and a sliding piece (23) protruding from the outer surface of the inner tube (4), and is constructed by slidably fitting the sliding piece (23) into the slit (22).SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a telescopic bracket for scaffold construction used when constructing scaffolds at construction sites and the like.

Background Art

[0002] Conventionally, for example, a telescopic bracket used for a temporary scaffold at a construction site or the like includes an outer pipe that protrudes horizontally while being detachably attached to a support column or the like of a scaffold structure, and an inner pipe that is slidably inserted into the outer pipe. Thus, a telescopic pipe that can be telescoped in the protruding direction is constituted. At that time, between the outer pipe and the inner pipe, a guide mechanism that guides axial sliding while preventing circumferential rotation, and a lock mechanism that locks and fixes the tip of a bolt means screwed in from the outer pipe to the inner pipe are provided. Incidentally, a scaffold board is mounted on the telescopic pipe to form a working floor surface.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] As shown in Patent Documents 1 and 2, in the telescopic pipe of the conventional telescopic bracket, a slit that extends long in the axial direction is formed in the inner pipe, and a bolt is screwed into a nut fixed to the lower part of the outer pipe. The bolt is inserted through the insertion hole of the outer pipe and into the inside of the inner pipe from the slit.

[0005] As a result, when the inner tube slides against the outer tube, the bolt is inserted into the slit of the inner tube from the outer tube, so the inner tube slides while being guided in the axial direction, with circumferential rotation prevented. When the inner tube is in the predetermined expanded / contracted state, tightening the bolt locks it in place as the tip of the bolt presses against the inner surface of the inner tube.

[0006] Therefore, in the conventional technology, the two mechanisms, the guide mechanism and the locking mechanism, are composed of a slit formed in the inner tube and a bolt screwed in from the outer tube. In other words, a single means combining the slit and the bolt is configured to serve both the guiding and locking functions.

[0007] However, when the telescopic tube is used in its extended state, the inner tube, which protrudes from the outer tube, has a long slit formed in it, extending from the tail end held by the outer tube to near the tip, thus reducing its strength. As a result, when subjected to a load from the mounted scaffolding board, it may bend and deform downwards. Furthermore, if the inner tube bends and deforms, it will hinder the extension and retraction of the telescopic tube.

[0008] The present invention aims to provide an expandable bracket for scaffolding construction, which has an expandable tube configured so as not to reduce the strength of the inner tube by separately configuring the guide mechanism and the locking mechanism. [Means for solving the problem]

[0009] Therefore, in order to solve the above problems, the present invention provides a means to construct an axially expandable and contractible tube comprising an outer tube fixed at its tail end to a scaffolding structure and an inner tube slidably inserted from the tip of the outer tube, a guide mechanism that guides the axial sliding of the outer tube while preventing the inner tube from rotating in the circumferential direction, and a locking mechanism that locks and fixes the inner tube so as to be unable to slide, wherein the locking mechanism is configured by locking and fixing a bolt means, which is screwed through the outer tube so as to be able to move back and forth, to the outer surface of the inner tube. The outer tube is configured such that a support frame is extended diagonally downward from the lower part of its axial midpoint via a support bracket, and the lower end of the support frame is fixed to the scaffolding structure. The guide mechanism is an outer tube Located at the lower part and crossing the support bracket It is constructed by comprising a slit extending in the axial direction and a sliding piece protruding from the outer surface of the inner tube, with the sliding piece being slidably fitted into the slit. The support fitting is provided with a groove through which the sliding piece passes. It's at a single point.

[0010] In a preferred embodiment, the outer tube is configured such that a support frame is extended diagonally downward from the lower part of the axial middle section via a support fitting, and the lower end of the support frame is fixed to the scaffolding structure, the slit of the guide mechanism is located at the lower part of the outer tube and is formed in an axial region that crosses the support fitting, the support fitting is composed of a groove-shaped member having a bottom wall and side walls, with the bottom wall separated from the slit and the side walls fixed to the outer tube on both sides of the slit.

[0011] Preferably, the locking mechanism comprises a through hole formed in the lower part of the tip of the outer tube, a nut means fixed to the lower part of the outer tube so as to communicate with the through hole, and a bolt means screwed into the nut means so as to be able to move back and forth, and is configured to lock and fix the tip of the bolt means inserted through the through hole to the lower part of the inner tube, and the nut means is fixed in a state in which the arcuate surface formed on its upper surface overlaps with the outer circumferential surface of the outer tube, and the width W2 of the arcuate surface of the nut means is formed to be larger than the width W1 of the slit with respect to the width in the circumferential direction of the outer tube. [Effects of the Invention]

[0012] According to the present invention, the locking mechanism 21 is configured by locking and fixing a bolt means 29, which is screwed through the outer tube 3 so as to be able to move back and forth, to the outer surface of the inner tube 4. The guide mechanism 20 comprises an axially extending slit 22 formed in the outer tube 3 and a sliding piece 23 protruding from the outer surface of the inner tube 4, and is configured by slidably fitting the sliding piece 23 into the slit 22. By configuring the guide mechanism 20 and the locking mechanism 21 separately in this way, it is possible to resolve the problem of reduced strength of the inner tube 4. [Brief explanation of the drawing]

[0013] [Figure 1]It is a perspective view showing an example of use of a telescopic bracket according to an embodiment of the present invention. [Figure 2] Examples of use of the telescopic bracket are shown. (A) and (B) are side views showing examples of use in which a scaffolding board with a hook provided with a cloth frame is mounted, showing an example of use with the telescopic tube contracted and an example of use with the telescopic tube extended, respectively. (B) and (C) are side views showing examples of use in which a scaffolding board without a hook of a placement type is mounted, showing an example of use with the telescopic tube contracted and an example of use with the telescopic tube extended, respectively. [Figure 3] It is a perspective view showing the telescopic bracket in a disassembled state. [Figure 4] It is a longitudinal sectional view showing a state where the inner tube is pulled out from the outer tube. [Figure 5] It is a longitudinal sectional view showing a state where the inner tube is inserted into the outer tube and the inner tube is extended. [Figure 6] It is a longitudinal sectional view showing an enlarged view of the insertion portion of the outer tube and the inner tube. [Figure 7] Cross-sections of the insertion portion of the outer tube and the inner tube are shown. (A) is a sectional view taken along line A-A of FIG. 6, (B) is a sectional view taken along line B-B of FIG. 6, and (C) is a sectional view taken along line C-C of FIG. 6. [Figure 8] Regarding a comparative example for the present invention, a first comparative example in which a slit is formed in the inner tube is shown. (A) is a longitudinal sectional view with the inner tube in a contracted state, and (B) is a longitudinal sectional view with the inner tube in an extended state. [Figure 9] Regarding a comparative example for the present invention, a second comparative example in which a concave groove is formed in the inner tube is shown. (A) is a longitudinal sectional view with the inner tube in a contracted state, and (B) is a longitudinal sectional view with the inner tube in an extended state.

Embodiments for Carrying Out the Invention

[0014] The preferred embodiments of the present invention will be described in detail below based on the drawings.

[0015] FIG. 1 illustrates a telescopic bracket for constructing a temporary scaffolding according to an embodiment of the present invention. In the case of the illustration, the temporary scaffolding structure 1 shows a framed scaffolding, but a single-pipe scaffolding may also be used. The telescopic bracket 2 is attached to the support portion 1a of the scaffolding structure 1.

[0016] The telescopic bracket 2 is composed of an outer tube 3 whose tail end is fixed to the support column 1a and an inner tube 4 slidably inserted from the tip of the outer tube 3, forming a telescopic tube 5 that can be telescopically extended and retracted in the axial direction. A support frame 6 is extended obliquely downward from the middle part in the axial direction of the outer tube 3, and is connected by a reinforcing frame 7 extending substantially vertically between the outer tube 3 and the support frame 6. Incidentally, the outer tube 3, the inner tube 4, the support frame 6, and the reinforcing frame 7 are each formed by a round metal pipe.

[0017] In the case of the illustrated embodiment, fastening means 9 such as a clamp fitting is attached to a pedestal fitting 8 fixed to the reinforcing frame 7 by welding or the like via bolts 10a (see FIG. 3) and nuts 10b (see FIG. 4). By fastening the fastening means 9 to the support column 1a, the telescopic bracket 2 is configured to be fixed to the support column 1a. At this time, due to the fastening of the fastening means 9, the contact member 11 provided at the tail end of the outer tube 3 is fixed in a state of being pressed against the surface of the support column 1a. Further, a support member 12 provided at the lower end of the reinforcing frame 7 is supported on the surface of the support column 1a at a lower position and is configured to support the downward load of the telescopic tube 5.

[0018] However, the configuration for attaching the telescopic bracket 2 to the support column 1a is not the object of the present invention, and of course, it is not limited to the illustrated configuration, and a wedge fastening method or other configurations as disclosed in the above-mentioned Patent Document 1 may be adopted.

[0019] As shown in FIG. 2, in the state where the telescopic bracket 2 is attached to the support column 1a, a scaffold board is mounted on the telescopic tube 5 to provide a working floor surface. [[ID=1 and 15]]

[0020] Figures 2(A) and 2(B) show examples of use in which a scaffolding board 13 with hooks and a fabric frame is mounted on an expandable tube 5. As shown in Figure 2(A), when mounting a narrow scaffolding board 13a (for example, with a width of 240 mm), the expandable tube 5 is used with the inner tube 4 retracted and stored in the outer tube 3, and the scaffolding board 13a is mounted with the left and right hooks 14, 14 engaged with the outer surface of the outer tube 3. In contrast, as shown in Figure 2(B), when mounting a wide scaffolding board 13b (for example, with a width of 500 mm), the expandable tube 5 is used with the inner tube 4 extended and protruding from the outer tube 3, and the scaffolding board 13b is mounted with the left and right hooks 14, 14 engaged with the outer surface of the tail end of the outer tube 3 and the outer surface of the tip of the inner tube 4.

[0021] Figures 2(C) and 2(D) show examples of use in which a hookless scaffolding board 15 of the mounting type is mounted on the telescopic pipe 5. As shown in Figure 2(C), when mounting a scaffolding board 15 of a predetermined width (for example, a width dimension of 253 mm), the telescopic pipe 5 is used with the inner pipe 4 retracted and stored in the outer pipe 3, and the scaffolding board 15 is mounted on top of the outer pipe 3 and fixed by any means. In contrast, as shown in Figure 2(D), when mounting two scaffolding boards 15, 15 side by side, the telescopic pipe 5 is used with the inner pipe 4 extended and protruding from the outer pipe 3, one scaffolding board 15 is mounted on top of the outer pipe 3, and the other scaffolding board 15 is mounted across the tip of the outer pipe 3 and the tip of the inner pipe 4, and each is fixed by any means.

[0022] In the illustrated embodiment, the inner tube 4 has a sleeve 16 fixed to its tip by welding or the like. The outer diameter of the sleeve 16 is formed to be approximately equal to the outer diameter of the outer tube 3, and when the inner tube 4 is contracted, the opposing end faces of the sleeve 16 and the outer tube 3 come into close proximity or contact with each other.

[0023] As shown in Figures 4 and 5, the sleeve 16 is provided with an end flange 17, to which a nut 18 located at the center of the sleeve 16 is fixed by welding or the like, and a hole 19 facing the nut 18 is provided. This configuration allows fastening means similar to the fastening means 9 such as the clamp fittings described above to be screwed onto the nut 18 via a mounting bolt, as needed.

[0024] In the illustrated embodiment, as shown in Figure 6, the inner diameter D1 of the outer tube 3 and the outer diameter D2 of the inner tube 4 constituting the expansion joint 5 are formed such that D1 = D2 + S, when the upper part of the outer surface of the inner tube 4 is in contact with the upper part of the inner surface of the outer tube 3, a gap S is formed at the bottom.

[0025] As shown in Figures 3 to 7, the telescopic tube 5 is equipped with a guide mechanism 20 that guides the axial sliding of the inner tube 4 while preventing circumferential rotation of the inner tube 4, and a locking mechanism 21 that locks and fixes the inner tube 4 in a way that prevents sliding. The guide mechanism 20 and the locking mechanism 21 are each configured as dedicated components. In other words, the guide mechanism 20 is intended to guide the sliding of the inner tube 4 in a state where it cannot rotate, and the locking mechanism 21 is intended to fix the inner tube 4 in a state where it cannot slide when it is extended or retracted.

[0026] (Guide mechanism) Therefore, the guide mechanism 20 is composed of an axially extending slit 22 formed in the lower part of the outer tube 3 and a sliding piece 23 protruding from the lower outer surface near the tail end (insertion end relative to the outer tube) of the inner tube 4, and the sliding piece 23 is slidably fitted into the interior of the slit 22 beyond the gap S.

[0027] The sliding piece 23 is formed, for example, by a bolt with a head. The shaft portion 23a is inserted into the lower part of the inner tube 4 and screwed in, and the head portion 23b is slidably inserted into the slit 22. The length of the slit 22 is formed to correspond to the difference in length between when the inner tube 4 is contracted and when it is extended relative to the outer tube 3. Therefore, the head portion 23b of the sliding piece 23 reciprocates between the two ends 22a and 22b of the slit 22. That is, when the inner tube 4 is contracted, it is located at one end 22a facing the tail end of the outer tube 3, and when the inner tube 4 is extended, it is located at the other end 15b facing the tip end of the outer tube 3, and slides along the slit 22 by accompanying the expansion and contraction movement of the inner tube 4.

[0028] Thus, the slit 22 constituting the guide mechanism 20 is formed in the outer tube 3 and not in the inner tube 4 as in the prior art. In the illustrated embodiment, the inner tube 4 has no notches such as slits, except for a small female screw hole formed for screwing in the shaft portion 23a of the sliding piece 23, and does not have anything along its entire length that would cause a reduction in strength.

[0029] Therefore, when the inner pipe 4 is extended and the scaffolding board is mounted on the telescopic pipe 5 (see Figures 2(B) and 2(D)), the inner pipe 4 can suitably withstand the load and there is no risk of it bending and deforming downward as in the conventional technology.

[0030] Incidentally, although the outer tube 3 has its own strength reduced by forming a slit 22, it can withstand loads effectively because its axial middle section is supported from below by the support frame 6.

[0031] In the illustrated embodiment, a support bracket 24 is fixed to the lower part of the axial middle portion of the outer tube 3 by welding or the like, and the upper end of the support frame 6 is fixed to the support bracket 24 by welding or the like.

[0032] As shown in Figures 6 and 7(B), the support bracket 24 is composed of a groove-shaped member having a bottom wall 25 and side walls 26, 26. The bottom wall 25 is separated downward from the slit 22, and the side walls 26, 26 are fixed to the outer surface of the outer tube 3 on both sides of the slit 22 by welding or the like. Therefore, even though the slit 22 extends axially across the support bracket 24, a groove 24a facing the slit 22 is formed in the support bracket 24, and when the inner tube 4 is extended or retracted, the head 23b of the sliding piece 23 passes through the groove 24a, so the sliding of the head 23b is not hindered.

[0033] Furthermore, since the support bracket 24 is fixed to the outer surface of the outer tube 3 in a bridging manner across the slit 22, even when the outer tube 3 is subjected to a crushing load from above the support frame 6, deformation of the slit 22, which would cause crushing, can be effectively prevented.

[0034] (Locking mechanism) As shown in Figures 6 and 7(A), the locking mechanism 21 consists of an insertion hole 27 formed in the lower part of the tip of the outer tube 3, a nut means 28 fixed to the lower part of the outer tube 3 so as to communicate with the insertion hole 27, and a bolt means 29 screwed into the nut means 28 so as to be able to move back and forth. The tip of the bolt means 29 inserted through the insertion hole 27 is configured to lock and fix to the lower part of the inner tube 4.

[0035] In the illustrated embodiment, the insertion hole 27 and the nut means 28 are located near the end 22b of the slit 22. The nut means 28 is formed from a disc-shaped member with an arc-shaped cross-section and an arc-shaped surface on its upper surface, and is fixed to the outer surface of the outer tube 3 by welding or the like with the arc-shaped surface overlapping it.

[0036] In this case, as shown in Figures 7(A) and 7(B), the width W2 of the arcuate surface of the nut means 28 is formed to be larger than the width W1 of the slit 22 with respect to the width of the outer tube 3 in the circumferential direction. As a result, the nut means 28 does not directly straddle the slit 22, but reinforces the outer tube 3 over a width W2 near its end 22b.

[0037] In this way, the locking mechanism 21 allows the inner tube 4 to expand and contract (axial movement) by loosening the bolt means 29, and when it is in a predetermined expanded and contracted position, the tip is locked to the inner tube 4 by tightening the bolt means 29, thereby locking the inner tube 4 so that it cannot expand or contract.

[0038] (Comparative Example 1) Figure 8 shows a first comparative example of the present invention. Similar to the prior art described above, the expansion joint has an axially elongated slit 22X formed in the inner tube 4X, and a bolt 29X is screwed into a nut 28X fixed to the lower part of the outer tube 3X. In this case, the bolt 29X is inserted through the insertion hole in the outer tube 3X and into the interior of the inner tube 4X from the slit 22X.

[0039] Since the bolt 29X is inserted from the outer tube 3X into the slit 22X of the inner tube 4X, the inner tube 4X is able to slide while being guided in the axial direction, with circumferential rotation prevented, thus forming a guide mechanism. When the inner tube 4X is in a predetermined extended or retracted state, tightening the bolt 29X will cause the tip of the bolt 29X to press against the inner surface of the inner tube 4X, thereby locking and fixing it in place, thus forming a locking mechanism.

[0040] Incidentally, when the telescopic tube is used in its extended state, the inner tube 4X, which protrudes from the outer tube 3X, forms a long slit 22X that extends from the tail end held by the outer tube to the vicinity of the tip. As a result, its strength is reduced, and as shown by the dashed line in Figure 8(B), it may bend and deform downward when subjected to a load from above.

[0041] In contrast to the first comparative example, according to the present invention, the inner tube 4 in the extended state possesses sufficient strength and is not susceptible to bending deformation, as described above.

[0042] (Comparative Example 2) Figure 9 shows a second comparative example of the present invention. The inner tube 4Y has a groove 22Y that extends long in the axial direction, instead of the slit 22X of the first comparative example, and a bolt 29X is screwed into a nut 28Y fixed to the lower part of the outer tube 3Y. In this case, the bolt 29Y is inserted into the groove 22Y by passing through the insertion hole of the outer tube 3Y.

[0043] Since the bolt 29Y is inserted from the outer tube 3Y into the groove 22Y of the inner tube 4Y, the inner tube 4Y is prevented from rotating in the circumferential direction and is slidable while being guided in the axial direction, thus forming a guide mechanism. When the inner tube 4Y is in a predetermined extended or retracted state, tightening the bolt 29Y locks the inner tube 4Y in place by pressing the tip of the bolt 29Y against the bottom of the groove 22Y, thus forming a locking mechanism.

[0044] Incidentally, when the telescopic tube is used in its extended state, the inner tube 4Y, which protrudes from the outer tube 3Y, forms a long groove 22Y extending from the tail end held by the outer tube to the vicinity of the tip. As a result, its strength is reduced, and as shown by the dashed line in Figure 9(B), it may bend and deform downwards when subjected to a load from above.

[0045] In contrast to this second comparative example, according to the present invention, the inner tube 4 in the extended state possesses sufficient strength and is not susceptible to bending deformation, as described above. [Explanation of Symbols]

[0046] 1. Scaffolding structure 1a Strut part 2 Telescopic brackets 3 outer tube 4 Inner tube 5 Telescopic tube 6. Support frame 7. Reinforcement frame 8. Base fittings 9 Fastening means 10a bolt 10b Nut 11 Contact member 12 Joint material 13a, 13b Scaffolding board with hooks 14 hooks 15 Scaffolding planks without hooks 16 sleeves 17 End face flange 18 nuts 19 holes 20 Guide mechanism 21 Locking mechanism 22 slits 22a, 22b ends 23 Sliding piece 23a Shaft 23b Head 24 Support brackets 24a Mizoro 25 Bottom wall 26 side wall 27 Through hole 28 Nut method 29 Bolt means

Claims

1. In a telescopic bracket for scaffolding construction, an outer tube is fixed at its tail end to a scaffolding structure, and an inner tube is slidably inserted from the tip of the outer tube, forming an axially expandable and contractible tube. The bracket is provided with a guide mechanism that guides the axial sliding of the outer tube and the inner tube while preventing the inner tube from rotating in the circumferential direction, and a locking mechanism that locks and fixes the inner tube so that it cannot slide. The locking mechanism (21) is configured by locking and fixing a bolt (29), which is screwed through the outer tube (3) and is movable back and forth, to the outer surface of the inner tube (4). The outer tube (3) is configured such that a support frame (6) extends diagonally downward from the lower part of the axial middle section via a support bracket (24), and the lower end of the support frame is fixed to the scaffolding structure. The guide mechanism (20) comprises a slit (22) located at the lower part of the outer tube (3) and extending axially in a region that crosses the support fitting (24), and a sliding piece (23) protruding from the outer surface of the inner tube (4), and is constructed by slidably fitting the sliding piece (23) into the slit (22). The support fitting (24) is characterized by having a groove (24a) through which the sliding piece (23) passes, and is an extendable bracket for constructing scaffolding.

2. The outer tube is configured such that a support frame (6) is extended diagonally downward from the lower part of the axial middle section via a support bracket (24), and the lower end of the support frame is fixed to the scaffolding structure. The slit (22) of the guide mechanism (20) is located at the lower part of the outer tube and is formed in an axial region that crosses the support fitting. The support fitting (24) is composed of a channel-shaped member having a bottom wall (25) and side walls (26, 26), and the side walls are fixed to the outer pipe (3) on both sides of the slit with the bottom wall separated from the slit, as described in claim 1.

3. The locking mechanism (21) consists of a through hole (27) formed in the lower part of the tip of the outer tube, a nut means (28) fixed to the lower part of the outer tube so as to communicate with the through hole, and a bolt means (29) screwed into the nut means so as to be able to move back and forth, and is configured to lock and fix the tip of the bolt means that has been inserted through the through hole to the lower part of the inner tube (4). The nut means (28) is fixed in a state in which the arcuate surface formed on its upper surface is superimposed on the outer surface of the outer tube. The telescopic bracket for scaffolding construction according to claim 1 or 2, characterized in that, with respect to the width of the outer tube in the circumferential direction, the width (W2) of the arcuate surface of the nut means (28) is formed to be larger than the width (W1) of the slit (22).

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