Structure for preventing the adjustment pin from falling out in pipe supports

Abstract

To improve a problem that an adjustment pin in a pipe support may unintentionally come out of an adjustment hole during transportation and that the workability of locking and unlocking the adjustment pin is poor. [Solution] The device is configured to include a lock portion 5 formed on the end of the adjustment pin 4 that is inserted toward the adjustment hole, and a lever 6 that is rotatably supported on the lock portion 5 and can pass through the adjustment hole only when it is in a specified rotational position. [Effect] Insertion and removal is possible only when the lever 6 is in the insertion / removal position, and the insertion and removal of the adjustment pin 4 is done simply by rotating the lever 6 to the insertion / removal position, making it easy and efficient to do. In addition, if the lever 6 is in a position other than the insertion / removal position, the adjustment pin 4 will not come out of the adjustment hole 2a, 3a, preventing the occurrence of unexpected accidents.

Description

[Technical field]

[0001] The present invention relates to a structure for preventing the adjustment pin from falling out of a pipe support, which reliably prevents the inner and outer tubes of the pipe support from being separated due to the adjustment pin coming out of the adjustment hole during transportation. [Background technology]

[0002] When constructing a concrete structure, concrete is poured into a formwork. At this time, for example, a pipe support is used to support the formwork from the lower floor or below when pouring a slab.

[0003] Conventionally, this pipe support has been roughly constructed as a double tube, and its length can be adjusted. The length adjustment structure is such that opposing adjustment holes are formed in the diametric direction of the fitting portion of the outer tube and the inner tube at the same pitch in the axial direction, and adjustment pins are inserted into the adjustment holes to fix the fitting position when the overall length of the pipe support is adjusted. In addition, conventional pipe supports have washers that come into contact with the installation surface or the formwork surface at the ends of the outer tube and the inner tube opposite to the fitting portions.

[0004] The above-mentioned adjustment pin is simply inserted into the adjustment hole, so there is a problem that it easily falls out of the adjustment hole. Therefore, in the past, for example, Patent Document 1 (Japanese Utility Model Application Laid-Open Publication No. 61-20650) shows a configuration in which a locking receiving portion is provided at the tip of the adjustment pin that penetrates the adjustment hole and protrudes, using a through hole or a circumferential groove, and a locking tool such as a pin or a clamping clip is detachably attached to the locking receiving portion.

[0005] Furthermore, Patent Document 2 (Japanese Utility Model Application Publication No. 6-82284) shows a configuration in which, when an adjustment pin passes through an adjustment hole, an elastic embracing arm is formed that surrounds a circumferential surface exceeding the diameter of the outer tube, centered on the adjustment pin.

[0006] Furthermore, Patent Document 3 (Utility Model Registration No. 3231399) shows a configuration in which the tip surface of the adjustment pin that protrudes through the adjustment hole is provided with a stopper made of a hard ball that elastically protrudes outward in the axial direction of the tip.

[0007] In Patent Documents 1 and 3, the diameter of the tip of the external adjustment pin that passes through the adjustment hole is made larger than the diameter of the adjustment hole to prevent the adjustment pin from falling out of the adjustment hole. However, in Patent Document 1, a locking device such as a pin or a clamping clip is simply attached to the locking receiving portion formed at the tip of the adjustment pin, so there is a possibility that the locking device may accidentally come off the locking receiving portion at the work site.

[0008] In addition, in Patent Document 2, when the adjustment pin starts to be inserted into the adjustment hole and the tip of the adjustment pin penetrates the adjustment hole and protrudes, if the holding arm exceeds the diameter of the outer tube, the holding arm is wound (holds) around the periphery of the outer tube with an elastic force that narrows the gap between both ends of the holding arm to prevent the adjustment pin from falling out of the adjustment hole. However, in Patent Document 2, even if the adjustment pin is inserted into the adjustment hole, if the holding arm gets caught, both ends of the holding arm open, and the diameter of the outer tube is exceeded in the direction in which the adjustment pin falls out, the elasticity of the holding arm may act to cause the adjustment pin to fall out.

[0009] Furthermore, in Patent Document 3, the stopper made of a hard ball is adapted to temporarily retract in the axial direction of the adjustment pin due to elasticity when passing through the adjustment hole, and to protrude in the radial outward direction of the adjustment pin due to elasticity after passing through. However, in Patent Document 3, since the hard ball is freely retracted due to elasticity as described above, when the adjustment pin is moved in the opposite direction to the direction of insertion into the adjustment hole, although there is some interference, the hard ball easily retracts into the shaft with the same force as that used for insertion, and there is a possibility that the function of the stopper will be lost.

[0010] On the other hand, pipe supports used to be separated into an adjustment pin, outer tube, and inner tube, and were transported separately. However, in recent years, some have come to have the adjustment pin already attached to the outer tube, and in order to improve transportation efficiency, they are now transported as a single unit with the inner tube inserted into the outer tube to shorten the overall length, and the adjustment pin inserted into the adjustment hole.

[0011] As described above, the conventional structures for preventing the adjustment pin from falling out of the adjustment hole in Patent Documents 1 to 3 are believed to have been able to prevent the adjustment pin from falling out of the adjustment hole in the "normal use" of the pipe support, that is, when the pipe support is erected between the formwork of the slab (ceiling surface) of the upper floor and the slab (floor surface) of the current floor, in a usage situation in which a vertical load is applied to the adjustment pin through the inner and outer pipes (of the adjustment holes).

[0012] However, in light of current transportation conditions, firstly, the pipe supports are transported sideways, for example loaded onto the bed of a truck, with the axial directions of the inner and outer pipes nearly parallel to the installation surface, so that no vertical load is applied to the adjustment pin. Furthermore, there is a possibility that the hard balls of Patent Document 3 will retract when adjacent pipe supports come into contact with each other, causing the pipe supports to get caught on each other and causing the pins and clamping clips and other fastening devices of Patent Document 1, or the embracing arms of Patent Document 2, to exceed the diameter of the outer pipe in the direction in which the adjustment pin comes out.

[0013] If the adjustment pin falls out of the adjustment hole during transportation, the inner and outer pipes may separate when the pipe support is unloaded from the truck, and may fall on a worker's feet and cause injury. There is also a risk that the pipe may fall unintentionally on the site and cause injury to a worker. In fact, several such incidents have occurred on site in the past, and it is expected that they will continue to occur in the future unless some kind of measures are taken.

[0014] In order to solve the above problems, the applicant proposed in Patent Application No. 2022-565630 (Patent Document 4) a structure for preventing the adjustment pin from falling out of a pipe support, in which a locking portion is formed at the end of the adjustment pin that is inserted toward the adjustment hole, and a key that is insertable and removable into this locking portion and has dimensions larger than the diameter of the adjustment hole, and in order to remove the key from the locking portion, the key is moved relative to the locking portion in the axial direction of the adjustment pin and in a horizontal direction perpendicular to the axis.

[0015] With the above-described anti-pullout structure, the key will not easily come off the lock portion unless the worker intentionally removes the adjustment pin from the pipe support, and therefore the adjustment pin will not inadvertently come off from the pipe support during transportation or for other reasons.

[0016] However, in Patent Document 4, the key had to be moved in the axial direction of the adjustment pin and in a horizontal direction perpendicular to the axis relative to the locking portion. Although this effectively prevented the key from coming out, it created another problem in that the operability of inserting and removing the key from the locking portion was poor. [Prior art documents] [Patent documents]

[0017] [Patent Document 1] Japanese Utility Model Application Publication No. 61-20650 [Patent Document 2] Japanese Utility Model Application Publication No. 6-82284 [Patent Document 3] Utility Model Registration No. 3231399 [Patent Document 4] Patent application No. 2022-565630 Summary of the Invention [Problem to be solved by the invention]

[0018] The problem to be solved is that there is no adjustment pin structure that can reliably prevent the adjustment pin from accidentally falling out of the adjustment hole during transportation and that allows for good operability in inserting and removing the adjustment pin from the adjustment hole. [Means for solving the problem]

[0019] In order to solve the above problems, the present invention provides a structure for preventing the adjustment pin from falling out in a pipe support comprising an outer tube, an inner tube for adjusting an overall axial length by being inserted into the outer tube, a plurality of adjustment holes formed in the axial direction at predetermined intervals in opposed diametric positions on the circumferential surfaces of the outer tube and the inner tube, and an adjustment pin for fixing the axial length by inserting the inner tube into the outer tube and adjusting the axial length, the structure comprising a locking portion formed on an end of the adjustment pin on the side that is inserted toward the adjustment hole, and a lever that is rotatably supported by the locking portion and that can pass through the adjustment hole only when the lever is in a predetermined rotation position. The adjustment pin will not come out of the adjustment hole even if the lever is not fixed at a position other than the insertion / removal position where the center of the lever is rotated to a position that coincides with the axis of the adjustment pin. The composition was as follows. Effect of the Invention

[0020] In the present invention, the adjustment pin passes through the adjustment hole only when the lever is in the predetermined rotation position in the lock section, in other words, if the lever comes into contact with something during transportation in the lock section and is unintentionally in a position other than the predetermined rotation position of the lever, it will not come out of the adjustment hole. On the other hand, as described above, if the lever is rotated to the predetermined rotation position in the lock section, the adjustment pin can be removed from the adjustment hole, making the operation extremely simple. [Brief description of the drawings]

[0021] [Figure 1] 1A and 1B are perspective views showing a pipe support employing the adjustment pin retention structure of the present invention. [Diagram 2] 1A and 1B are a front and upper perspective view of an adjustment pin, and FIG. [Diagram 3]1A is a top view of an adjustment pin using the structure of the present invention; FIG. 1B is a side view of the adjustment pin; and FIG. 1C is a front view of the adjustment pin. [Figure 4] 13(a), (b), and (c) are diagrams for explaining operating conditions. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] The present invention aims to prevent the adjustment pin from accidentally coming out of the adjustment hole of the pipe support and to improve the ease of inserting and removing the adjustment pin from the adjustment hole by providing a locking portion formed at the end of the adjustment pin on the side that is inserted toward the adjustment hole, and a lever that is rotatably supported by the locking portion and that can pass through the adjustment hole only when the lever is in the predetermined rotation position. The adjustment pin will not come out of the adjustment hole even if the lever is not fixed at a position other than the insertion / removal position where the center of the lever is rotated to a position that coincides with the axis of the adjustment pin. This was achieved by doing the following.

[0023] In Patent Document 4, while Patent Documents 1 to 3 lock the adjustment pin so that it does not come out of the adjustment hole, the simplicity of the lock for the operator and the simplification of the configuration were included. However, the locking device and holding arm can easily come off if they come into contact with the outside due to the operator's simplicity acting in the opposite way.

[0024] Therefore, Patent Document 4 assumes that a key in a locked state will inadvertently come into contact with the outside during transport and move, and so sacrifices ease of use and operability in order to remove the key from the lock, requiring movement in at least two directions in stages: the key is moved in the axial direction of the adjustment pin and in a horizontal direction perpendicular to that axis relative to the lock to remove it from the lock.

[0025] The present invention is a further development of Patent Document 4, and is based on the premise that the lever will inadvertently come into contact with the outside during transport and move from the correct locking position so as to prevent the adjustment pin from falling out of the adjustment hole in the pipe support. The present invention is structured so that the adjustment pin, including the lever, can pass through the adjustment hole even if the lever is in a position other than the correct locking position, in other words, only when the lever is in a specified rotation position.

[0026] Furthermore, with the above-described structure of the present invention, the adjustment pin can be inserted and removed from the adjustment hole in the pipe support simply by rotating the lever in the forward or reverse direction, thereby achieving both the ease of use and simplicity that were sacrificed in Patent Document 4.

[0027] In the above configuration, the present invention may be configured so that the locking portion is formed with a locking protrusion for locking the lever at a predetermined rotational position. In this way, the unlocked position of the lever in the locking portion (a predetermined rotational position where the adjustment pin can be inserted and removed from the adjustment hole) is maintained even while the adjustment pin is being inserted and removed from the adjustment hole, making the operation even easier.

[0028] From another point of view, the fact that the locking protrusion can maintain the lever in the predetermined rotation position means that the lever will not inadvertently rotate to the predetermined rotation position, which is the unlocked position. Therefore, this also has the effect of preventing the lever from accidentally coming into contact with the outside during transportation, causing the adjustment pin to fall out of the adjustment hole in the pipe support.

[0029] Furthermore, in the above configuration, the present invention may form an engagement recess at a connection portion of the adjustment pin with the locking portion, into which the inner periphery of the adjustment hole engages. In this way, even if the lever is in the unlocked position of the locking portion and the adjustment pin and the adjustment hole of the pipe support move relatively in the direction of coming out, the adjustment hole engages with the engagement recess just before reaching the locking portion, so that the adjustment pin will not easily come out of the adjustment hole with the relative movement as it is. EXAMPLES

[0030] Hereinafter, specific embodiments of the present invention will be described with reference to FIGS. A pipe support 1 supporting a formwork for pouring concrete comprises an outer pipe 2, an inner pipe 3 inserted into the outer pipe 2 to adjust the overall axial length, adjustment holes 2a (in the outer pipe 2) and 3a (in the inner pipe 3) formed in a plurality of axially spaced relation opposite to the diameter positions on the circumferential surfaces of the outer pipe 2 and the inner pipe 3, and an adjustment pin 4 for fixing the axial length by inserting the inner pipe 3 into the outer pipe 2 and adjusting the axial length and then inserting it into the communicating adjustment holes 2a, 3a.

[0031] The adjustment pin 4 has a pin body 4A and a locking portion 5 formed at the end of the pin body 4A on the side that is inserted toward the adjustment holes 2a, 3a (hereinafter referred to as the "insertion side"). An engagement recess 4B is formed at the connection site with the locking portion 5 on the insertion side of the pin body 4A, the diameter of which is smaller than that of the axial midpoint of the pin body 4A.

[0032] In addition, the adjustment pin 4 has a penetration prevention portion 4C formed on the end opposite to the end of the pin body 4A that is inserted toward the adjustment holes 2a, 3a in which the lock portion 5 is formed (hereinafter referred to as the "anti-insertion side").

[0033] Furthermore, the adjustment pin 4 is provided with a lever 6 that is rotatably supported by a lock portion 5 and that can pass through the adjustment hole only when the lever 6 is in a predetermined rotation position.

[0034] In this embodiment, the locking portion 5 is formed of the following elements on a base material 5A that is coaxial with the pin body 4A and connected to the tip of the pin body 4A. The entire base material 5A, except for the tip on the insertion side, is a columnar body with a circular cross section and the same diameter as the central part of the pin body 4A, and its rear end, which is the side opposite to the insertion side, is connected to the tip of the insertion side of the pin body 4A.

[0035] That is, the above-mentioned engagement recess 4B is interposed between the rear end of the base material 5A and the front end of the pin body 4A. That is, the rear end of the base material 5A and the pin body 4A have the same diameter, and the engagement recess 4B has a smaller diameter than the pin body 4A, so that the engagement recess 4B appears when the lock portion 5 (base material 5A) and the pin body 4A are connected.

[0036] In the base material 5A, opposing wall surfaces 5a, 5a are formed at a predetermined width apart from each other in the diameter direction centered on the axis of the base material 5A as shown in Fig. 3(c), and are formed by cutting away from the tip to a midpoint in the direction of the pin body 4A as shown in Fig. 3(a). In addition, the base material 5A has an operating portion 5B formed by an opposing space formed by the wall surfaces 5a, 5a.

[0037] In the wall surfaces 5a, 5a constituting the operating portion 5B, axial holes 5b, 5b are formed in a direction perpendicular to the direction in which the wall surfaces 5a, 5a face each other, at a midpoint in the axial direction of the adjustment pin 4 in the axial length of the base material 4A, and a pivot pin 5C that pivots the lever 6 is inserted through these holes.

[0038] In addition, on each of the opposing surfaces of the wall surfaces 5a, 5a, locking protrusions 5D are formed at four positions on one wall surface 5a in this example, spaced apart by the height of the lever 6 (described later) in a direction perpendicular to the direction parallel to the axis of the pin body 4A, centered on the axial holes 5b, 5b, for locking the lever 6 at the 0° (180°) position or the 90° (270°) position in this example.

[0039] The lever 6 is configured in the shape of a rectangular column (approximately a rectangular parallelepiped) with a width (direction) dimension being the distance between the opposing wall surfaces 5a, 5a in the locking portion 5, a height (direction) dimension being the axial direction of the pin body 4A and the base material 5A and a direction perpendicular to the direction of insertion into the axial hole 5b of the pivot pin 5C, and a length (direction) dimension being the axial direction of the pin body 4A and the base material 5A.

[0040] A hole 6a penetrating from front to back in the width direction is formed in the middle portion of the lever 6 in the longitudinal direction, and when the lever 6 is placed in the operating part 5B of the locking part 5, a pivot pin 5C is inserted into the shaft holes 5b, 5b and the hole 6a.

[0041] When the lever 6 is divided into one end and the other end in the length direction from the position where the hole 6a is formed, the length from one end to the hole 6a and the length from the hole 6a to the other end may be the same, but in this example, the former is made longer than the latter. Note that the former and latter lengths are set to dimensions such that the lever 6 will not be inserted into the adjustment holes 2a and 3a at any angle of the rotational orbit of the lever 6.

[0042] The effect of the above-described structure for preventing the adjustment pin 4 from falling out will be described. When inserting the adjustment pin 4 into the adjustment holes 2a, 3a, the center of the lever 6 in the height direction and width direction is rotated around the pivot pin 5C as the rotation axis to a position that coincides with the axis of the pin body 4A of the adjustment pin 4 and the base material 5A of the locking part 5. This position is the (predetermined) rotation position for inserting and removing the adjustment pin 4 into and from the adjustment holes 2a, 3a of the pipe support 1.

[0043] The lever 6 in the rotation position for insertion / removal (hereinafter, referred to as the insertion / removal position) is completely contained within the diameter of the pin body 4A and the base material 5A, that is, there is no part protruding outside the diameter. In this example, the lever 6 passes over the locking protrusion 5D and rotates to the insertion / removal position, and the rotation is restricted by the locking protrusion 5D at the insertion / removal position.

[0044] The adjustment pin 4 can be inserted into and removed from the adjustment holes 2a and 3a only in this insertion / removal position, and the insertion / removal operation (work) can be performed simply by rotating the lever 6. In this explanation, the adjustment pin 4 is inserted into the adjustment holes 3a, 2a and 2a, 3a, and with the lock portion 5 completely exposed from the outer tube 2, the lever 6 is rotated from the insertion / removal position by 90° or 270° (-90°) in this example, that is, to a position where the longitudinal direction of the lever 6 is perpendicular to the axes of the pin main body 4A and the base material 5A of the lock portion 5.

[0045] In this example, the position where the lever 6 is rotated 90° or -90° from the insertion / removal position is the position for locking the adjustment pin 4 so that it does not come out of the pipe support 1 (hereinafter referred to as the lock position), but as will be described later, locking is possible at any position other than the insertion / removal position.

[0046] When the lever 6 is in the locked position, one end and the other end in the length direction are centered on the hole 6a (pivot pin 5C in the locking portion 5) and protrude outside the diameter of the pin body 4A and the base material 5A. In this example, the lever 6 passes over the locking projection 5D and rotates to the locked position, and the rotation is restricted by the locking projection 5D at the locked position.

[0047] Next, with reference to Fig. 4, we will explain the effect of the fall-out prevention structure of the present invention in a situation where the adjusting pin 4 comes out of the pipe support 1. Note that Fig. 4 shows a situation where the pipe support 1 comes out of the adjusting pin 4, rather than the adjusting pin 4 coming out of the pipe support 1, in other words, a situation where the pipe support 1 moves relative to the adjusting pin 4 during transportation, causing the adjusting pin 4 to come out.

[0048] As shown in Figure 4(a), when the lever 6 is in the above-mentioned locked position, even if the pipe support 1 moves to the insertion side of the adjustment pin 4 (the side where the lock portion 5 is formed), one end and the other end of the lever 6 centered on the pivot pin 5C position in the longitudinal direction abuts against the outer peripheral surface outside the diameter of the adjustment hole 3a of the outer tube 2, so that the adjustment pin 4 will not come out.

[0049] Furthermore, as shown in Figure 4(b), when the locking portion 5 of the adjustment pin 4 is sufficiently inserted beyond the engagement recess 4B, the outer tube 2 and inner tube 3 of the pipe support 1 fit into and engage with the engagement recess 4B before the situation shown in Figure 4(a) is reached, thereby preventing the adjustment pin 4 from coming loose.

[0050] As shown in Figure 4(c), when the pipe support 1 is moved to the anti-insertion side (the side where the penetration prevention portion 4C is formed), the penetration prevention portion 4C, which has a larger diameter than the adjustment holes 2a, 3a, abuts against the outer peripheral surface outside the diameter of the adjustment hole 3a of the outer pipe 2, so that the adjustment pin 4 does not come out.

[0051] As shown in Figures 4(d) and (e), even if the lever 6 is not set in the locked position, if the lever 6 is in a position other than the insertion / removal position, when one end or the other end of the lever 6 in the longitudinal direction centered on the pivot pin 5C position first abuts against the outer peripheral surface outside the diameter of the adjustment hole 3a of the outer tube 2 and rotates toward the tip of the adjustment pin 4, the other end or the one end opposite the abutting side rotates in the opposite direction, resulting in the state shown in Figure 4(a), and the adjustment pin 4 will not come out.

[0052] As described above, the anti-removal structure of the adjustment pin 4 of the present invention can be inserted and removed only when the lever 6 is in the insertion / removal position, and the insertion and removal of the adjustment pin 4 can be performed simply by rotating the lever 6 to the insertion / removal position, making it easy and efficient to do. Furthermore, if the lever 6 is in a position other than the insertion / removal position, the adjustment pin 4 will not come out of the adjustment holes 2a, 3a when the inner tube 3 is inserted in the outer tube 2 during transportation, so no unexpected accidents will occur. [Explanation of symbols]

[0053] 1 Pipe Support 2 outer tube 2a adjustment hole 3 Inner tube 3a adjustment hole 4 Adjustment pin 4A pin body 4B Engagement recess 4C Penetration prevention part 4a Lock hole 5 Locking section 5A base material 5B Operating part 5C Pivot pin 5D Locking protrusion 6 Lever 6a hole

Claims

1. A structure for preventing the adjustment pins from falling out in a pipe support comprising an outer tube, an inner tube for adjusting an overall axial length by being inserted into the outer tube, a plurality of adjustment holes formed in the circumferential surfaces of the outer tube and the inner tube at diametric positions and spaced apart from each other in the axial direction, and adjustment pins for inserting the inner tube into the outer tube to adjust the axial length and then inserting the adjustment pins into the respective adjustment holes to fix the axial length, The adjustment pin removal structure for a pipe support includes a locking portion formed on the end of the adjustment pin that is inserted toward the adjustment hole, and a lever that is rotatably supported on the locking portion and can pass through the adjustment hole only when it is in a predetermined rotation position, and is configured so that the adjustment pin will not fall out of the adjustment hole even if the lever is not fixed at any position other than the insertion / removal position where the center of the lever is rotated to a position that coincides with the axis of the adjustment pin.

2. 2. The structure for preventing the adjustment pin from falling out of a pipe support according to claim 1, wherein said locking portion is formed with a locking projection for locking said lever at a predetermined rotational position.

3. 3. The structure for preventing the adjustment pin from slipping out of a pipe support according to claim 1, wherein an engagement recess for engaging with an inner periphery of the adjustment hole is formed at a connection portion of the adjustment pin with the lock portion.

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