JP7710232B2 - Height adjustment device - Google Patents

Description

This invention relates to a height adjustment device used in temporary scaffolding and the like to adjust the height of various support members.

Temporary scaffolding generally consists of multiple support members arranged along the exterior wall of a building, connected by beams, with scaffolding boards fixed along the beams. A height adjustment device, a so-called jack device, is often placed at the bottom end of the support members to adjust the position of the bottom end of the support members. For example, one such height adjustment device is described in Patent Document 1.

JP 2010-1687 A

In temporary scaffolding such as the one described above, there are cases where it is necessary to adjust the position of the bottom end of the support member in the vertical direction relative to the ground at the installation location. For example, this can occur when the ground is inclined or uneven.

In the height adjustment device described in Patent Document 1, a support member that supports the lower end of the support member is screwed to a support shaft that rises from a base member placed on the ground. For this reason, when adjusting the height of the support member, it is necessary to rotate the support member around the support shaft. At this time, the amount of lift of the support member is about a few mm to a few cm per rotation around the shaft, so when the amount of height adjustment is large, the work is complicated and requires time and effort.

Therefore, the objective of this invention is to make it easier to adjust the height of support members used in structures such as temporary scaffolding.

In order to solve the above problems, this invention employs a height adjustment device that raises and lowers the bottom end position of a support member relative to a screw shaft that rises above the ground and has a male thread on its outer periphery, the height adjustment device comprising a first member having a female thread that screws into the male thread, the first member being rotatably supported by a base provided at one end and comprising a pair of opening and closing pieces on which the female thread is formed, the pair of opening and closing pieces being rotatable between a locked state in which the male thread and the female thread are engaged, and an open state in which the other end of the pair of opening and closing pieces is opened and the male thread and the female thread are separated.

Here, a configuration can be adopted that includes a second member connected to the first member and a rotation mechanism that rotates the pair of opening and closing pieces by raising and lowering the second member relative to the first member.

The rotation mechanism can also be configured to have the function of maintaining the locked state.

In each of these aspects, the rotation mechanism can be configured to include an action shaft that moves up and down together with the second member, an action protrusion provided on the action shaft, and an action groove provided on the first member into which the action protrusion fits, with the direction in which the action groove extends being inclined with respect to the axial direction of the action shaft.

In addition, a configuration can be adopted in which the anti-rotation protrusion provided on the working shaft fits into an anti-rotation groove provided on the first member, thereby preventing the working shaft from rotating around its axis.

This invention makes it easy to adjust the height of support members used in structures such as temporary scaffolding.

FIG. 1 is an enlarged perspective view of a main portion according to a first embodiment of the present invention; FIG. 11 is a perspective view showing a state in which the first member and the second member are brought close to each other; FIG. 11 is a perspective view showing a state in which the first member and the second member are separated from each other; FIG. 13 is an enlarged side view of a main part of the embodiment. IV-IV cross-sectional view of FIG. VV cross-sectional view of FIG. 3 (locked state) VV cross-sectional view of FIG. 3 (open state) FIG. 11 is an enlarged perspective view of a main portion according to a second embodiment of the present invention (locked state); FIG. 11 is an enlarged perspective view of a main part according to a second embodiment of the present invention (intermediate state); FIG. 11 is an enlarged perspective view of a main part according to a second embodiment of the present invention (open state); 6D is a perspective view of the first member in FIG. FIG. 1 is a perspective view showing a state in which the first embodiment is used; FIG. 11 is a perspective view showing a state in which the second embodiment is used;

A first embodiment of the invention is shown in Figures 1 to 5B and 8. This embodiment is a height adjustment device 1 used at the bottom of a structure such as temporary scaffolding. Generally, temporary scaffolding is made up of multiple support members P, P arranged along the outer wall of a building, connected by beams, with scaffolding boards fixed along the beams. The height adjustment device 1 is placed at the lower end of the support members P.

The height adjustment device 1 adjusts the position of the bottom end of the support member P relative to the ground. By adjusting the position of the bottom end of the support member P, even if the ground at the location where the structure is to be installed is inclined or uneven, it is possible to eliminate the gap between the structure and the ground and stabilize the installation state. The height adjustment device 1 assumes that the installation target is a screw shaft A that rises up from the ground in the vertical direction. As shown in Figure 8, the screw shaft A is fixed integrally to a plate-shaped base part B placed on the ground by welding or the like. A male screw part a is formed on the outer periphery of the screw shaft A.

The height adjustment device 1 includes a first member 30 having a female threaded portion 36 that screws into the male threaded portion a, and a second member 40 that is connected to the first member 30 and supports the lower end of the support member P.

The first member 30 is composed of an annular member that surrounds the screw shaft A around the axis. In this embodiment, the first member 30 is composed of a pair of opening and closing pieces 31, 32 that form an arc shape. As shown in FIG. 1, the pair of opening and closing pieces 31, 32 are supported rotatably by bases 33, 34, 35 provided at one end (hereinafter referred to as one end) along the circumferential direction. By rotating around the bases 33, 34, 35, the pair of opening and closing pieces 31, 32 can open and close the other end (hereinafter referred to as the other end) on the opposite side of the axis of the first member 30. However, in this embodiment, the pair of opening and closing pieces 31, 32 are each made of an arc-shaped member that extends from one end to the other end, but the cross-sectional shape of the pair of opening and closing pieces 31, 32 does not matter as long as they are members that surround the screw shaft A. Hereinafter, one of the pair of opening and closing pieces 31, 32 will be referred to as the first opening and closing piece 31, and the other as the second opening and closing piece 32.

The base 34 of the first opening/closing piece 31 is provided so as to protrude to the side at the vertical center of the first opening/closing piece 31. The bases 33, 35 of the second opening/closing piece 32 are provided so as to protrude to the side at a distance in the vertical direction. This allows the base 34 of the first opening/closing piece 31 to fit between the bases 33, 35 of the second opening/closing piece 32. The first opening/closing piece 31 and the second opening/closing piece 32 are supported so as to be freely rotatable by inserting the action shaft 41 described below into the holes 33a, 34a, 35a provided in the bases 33, 34, 35. The reference numeral 2 in the figure denotes a handle portion with which the operator grasps the height adjustment device 1 with his or her hand.

A female screw portion 36 is formed on the inner circumference of the first member 30. The female screw portion 36 is formed along the inner circumference of the pair of opening and closing pieces 31, 32. When the other ends of the first opening and closing piece 31 and the second opening and closing piece 32 are closed as the first opening and closing piece 31 and the second opening and closing piece 32 are opened, the male screw portion a of the screw shaft A and the female screw portion 36 are engaged in a locked state, and when the other ends of the first opening and closing piece 31 and the second opening and closing piece 32 are opened, the male screw portion a and the female screw portion 36 are disengaged in an open state. In the locked state, by rotating the first member 30 around the axis of the screw shaft A, the male screw portion a and the female screw portion 36 engage with each other, and the first member 30 rises and falls along the axial direction of the screw shaft A relative to the screw shaft A.

The rotation (opening and closing) of the first opening and closing piece 31 and the second opening and closing piece 32 is performed by a rotation mechanism 50. The rotation mechanism 50 functions by raising and lowering the action shaft 41, which functions as the rotation center of the first opening and closing piece 31 and the second opening and closing piece 32, together with the second member 40, relative to the first member 30. In the embodiment, the action shaft 41 is press-fitted and fixed into a hole 42a provided in the base 42 of the second member 40. However, the action shaft 41 and the second member 40 may be molded as an integrated member.

The action shaft 41 is provided with an action protrusion 51 that protrudes to the side. The action protrusion 51 fits into an action groove 52 formed in the hole 33a of the first member 30. Furthermore, in this embodiment, the action shaft 41 is provided with a rotation prevention protrusion 53 separate from the action protrusion 51. The rotation prevention protrusion 53 fits into a rotation prevention groove 54 formed in the hole 34a of the first member 30. The action protrusion 51 and the rotation prevention protrusion 53 are provided in different orientations along the axial direction of the action shaft 41.

The action groove 52 into which the action protrusion 51 fits is provided in a direction inclined with respect to the axial direction of the action shaft 41 (see Figures 3, 5A, and 5B). In addition, the anti-rotation groove 54 into which the anti-rotation protrusion 53 fits is provided parallel to the axial direction of the action shaft 41 (see Figure 4). Since the anti-rotation protrusion 53 fits into the anti-rotation groove 54 of the first member 30, even if the action shaft 41 moves up and down relative to the first member 30, the second opening and closing piece 32 and the action shaft 41 do not rotate relative to each other around the axis. Also, since the action protrusion 51 fits into the action groove 52 of the first member 30, when the action shaft 41 moves up and down relative to the first member 30, the first opening and closing piece 33 rotates relative to the action shaft 41 around the axis. Therefore, the other ends of the first opening and closing piece 31 and the second opening and closing piece 32 open and close due to the movement of the action shaft 41 up and down relative to the first member 30.

In this embodiment, the anti-rotation groove 54 is parallel to the axial direction of the action shaft 41, and the action groove 52 is inclined relative to the axial direction of the action shaft 41, but the extension directions of the action groove 52 and the anti-rotation groove 54 can be changed as long as the other ends of the first opening/closing piece 31 and the second opening/closing piece 32 are opened and closed by the raising and lowering of the action shaft 41 relative to the first member 30. For example, both the direction of the action groove 52 and the direction of the anti-rotation groove 54 may be inclined relative to the axial direction of the action shaft 41. In this case, both the protrusions 51, 53 and the grooves 52, 54 contribute to the opening and closing of the first opening/closing piece 31 and the second opening/closing piece 32.

The pivot mechanism 50 also has the function of maintaining the locked state of the height adjustment device 1 relative to the screw shaft A. That is, in this embodiment, the first opening/closing piece 31 and the second opening/closing piece 32 are maintained in a locked state and will not transition to an open state against the operator's will unless the action shaft 41 is pulled upward relative to the first member 30. At this time, if appropriate friction is generated between the action protrusion 51 and the action groove 52, the action shaft 41 will not come out of the first member 30 unless a certain degree of external force is applied to the action shaft 41. This makes it possible to more reliably maintain the locked state.

As shown in FIG. 3, if the inclination angle (obtuse angle) β of the action groove 52 (lower action groove 52b) relative to the horizontal direction when the action protrusion 51 is in the locked state is made smaller than the inclination angle (obtuse angle) α of the action groove 52 (upper action groove 52a) relative to the horizontal direction when the action protrusion 51 is in the open state, the locked state of the first opening/closing piece 31 and the second opening/closing piece 32 becomes more stable. In other words, it is preferable that the direction of the lower action groove 52b corresponding to the locked state is closer to the vertical direction, i.e., the axial direction of the action shaft 41, than the direction of the upper action groove 52a corresponding to the open state. This is also true when an inclination is set in the anti-rotation groove 54.

As described above, when the other ends of the first opening/closing piece 31 and the second opening/closing piece 32 are closed (locked state of the first member 30), the first member 30 is rotated around the axis of the screw shaft A, and while the male screw portion a and the female screw portion 36 are engaged, the first member 30 moves up and down along the axial direction of the screw shaft A relative to the screw shaft A. However, when the height to which the first member 30 is raised and lowered (hereinafter referred to as the adjustment height) is large, the number of times the first member 30 is rotated relative to the screw shaft A becomes very large. For this reason, the worker must rotate the first member 30 many times, which takes time and effort to do the work. However, according to this invention, the first member 30 is released from the locked state to the released state, so that the first member 30 is temporarily released from the screw shaft A, and the first member 30 can be instantly adjusted in position by locking the first member 30 at any axial position of the screw shaft A. This makes it possible to facilitate the work and shorten the work time. Subsequent fine adjustments to the height can be made by rotating the first member 30 around the screw axis A, as in the conventional method.

The second member 40 functions as a receiving member that supports the lower end of the support member P. The second member 40 is connected to the upper part of the first member 30, so that the load from the support member P and above is transmitted to the screw shaft A through the first member 30. The second member 40 has an annular receiving portion 3 on the inner diameter side of a peripheral wall portion 4 that is circular in plan view, on which the lower end of the support member P is placed. When the lower end of the support member P is placed on this receiving portion 3, the support member P is held by the peripheral wall portion 4, so that the support member P does not come off and fall off the second member 40.

As described above, the second member 40 has both the function of rotating the first opening/closing piece 31 and the second opening/closing piece 32 in the rotation mechanism 50 and the function of maintaining the first opening/closing piece 31 and the second opening/closing piece 32 in a locked state, and can also perform the function of supporting the support member P. This reduces the number of parts and simplifies the structure.

A second embodiment of the present invention is shown in Figures 6, 7, and 9. In this embodiment, a handle portion 2 for gripping the height adjustment device 1 by hand is provided on the first member 30. The rest of the configuration is the same as in the first embodiment, so a description will be omitted.

In each of the above embodiments, the use of the height adjustment device of the present invention has been described using a temporary scaffolding used at construction sites, etc. as an example, but the structures to which the height adjustment device of the present invention can be applied are not limited to temporary scaffolding, and can also be applied to other uses, such as temporary stages, temporary bridges, and prefabricated racks (shelves). Also, in each of the above embodiments, the material of each component is metal, but the material of the components may be other materials such as resin as long as it has a predetermined strength and durability.

REFERENCE SIGNS LIST 1 Height adjustment device 2 Handle portion 3 Receiving portion 4 Peripheral wall portion 30 First member 31, 32 Opening/closing piece 40 Second member 50 Rotation mechanism 51 Action protrusion 52 Action groove 53 Anti-rotation protrusion 54 Anti-rotation groove P Support member

Claims (3)

A height adjustment device for raising and lowering the lower end position of a support member (P) relative to a screw shaft (A) that rises above the ground and has a male screw portion (a) on its outer periphery,
A first member (30) having a female screw portion (36) that screws into the male screw portion (a),
The first member (30) is provided with a pair of opening and closing pieces (31, 32) that are rotatably supported by a base portion (33, 34, 35) provided at one end and on which the female screw portion (36) is formed,
the pair of opening/closing pieces (31, 32) are rotatable between a locked state in which the male screw portion (a) and the female screw portion (36) are engaged with each other and an open state in which the other ends of the pair of opening/closing pieces (31, 32) are opened and the male screw portion (a) and the female screw portion (36) are disengaged from each other;
A second member (40) connected to the first member (30);
a rotation mechanism (50) that rotates the pair of opening/closing pieces (31, 32) by raising and lowering the second member (40) relative to the first member (30),
The rotating mechanism (50) includes an action shaft (41) that moves up and down together with the second member (40), an action protrusion (51) provided on the action shaft (41), and an action groove (52) provided on the first member (30) into which the action protrusion (51) fits,
A height adjustment device in which the direction in which the action groove (52) extends is inclined with respect to the axial direction of the action shaft (41) . The height adjustment device according to claim 1 , wherein the rotation mechanism (50) has a function of maintaining the locked state. A height adjustment device as described in claim 1 or 2, wherein the operating shaft (41) is prevented from rotating around its axis by a rotation prevention protrusion (53) provided on the operating shaft (41) entering into a rotation prevention groove ( 54) provided on the first member (30) .