JPH11209981A - Strut support made of aluminum - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide strut support which is excellent in lightness and easy to adjust its length and handle. SOLUTION: One end of a tapped pipe 30 made of aluminum is fitted into a main pipe 20 made of aluminum, and end plates 40, 50 are provided, respectively, at the ends of the main pipe 20 and the tapped pipe 30. At a position where the tapped pipe 30 is inserted, a stopper 70 is provided on the circumferential wall of the main pipe 20, and an adjustment screw 60 for adjusting the length of strut support is provided on the tapped pipe 30. The stopper 70 fixes the lengths of the main pipe 20 and the tapped pipe 30 by inserting a casing 72 storing a stopper ball 71 into a housing 73, applying pressure to the head 72a of the casing 72 using a locking bolt 76 via a spring 75, and pressing the stopper ball 71 against a ridge 31. Since only the resiliency of the spring 75 is applied to the casing head 72a when the locking bolt 76 is loosened, the tapped hole 30 can be inserted into and retracted from the main pipe 20 with a slight force, and inadvertent dropping of the tapped pipe 30 from the main pipe 20 is also prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aluminum cutting beam support used in civil engineering work for burying electric wires, gas pipes, water and sewage pipes, telephone cable pipes and the like underground.

[0002]

2. Description of the Related Art When burying electric wires, gas pipes, water and sewage pipes, telephone cable pipes, etc. in the ground, or when repairing these pipes buried in the ground, when excavating a trench in the ground surface, A sheet pile is driven along both groove walls. The sheet pile is pressed against the groove wall directly or via a protruding material by the cutting beam support, thereby preventing collapse of the groove wall and ensuring work safety. For example, as shown in FIG.
No. 16214. In this case, a plurality of sheet piles 4 are driven along each groove wall 3 of the excavation groove 2 excavated on the ground surface 1, and the sheet piles 4 are fixed in common with the flared material 5. An extendable cutting beam support 6 is provided between the belly members 5 and 5 on both sides to support the belly members 5 and 5.

[0003] The cutting beam support 6 has a main pipe 7 formed of a cylindrical body and a screw pipe 8 fitted therein so as to be able to advance and retreat, and applies a tension force to the main pipe 7 and the screw pipe 8 with an adjusting screw 9 or the like. An inverted L-shaped end plate 10 is fixed to the rear end face of the main pipe 7, and a stopper 11 is attached to the upper face. Stopper 11
Consists of an inverted L-shaped bolt, and fixes the screw tube 8 to the main tube 7 by engaging with a screw groove 13 of a male screw 12 formed on the outer periphery of the screw tube 8 as shown in FIG. Screw tube 8
, An end plate 14 similar to the end plate 10 of the main pipe 7 is fixed to the front end face, and an adjusting screw 9 is screwed near the rear end.

[0004]

In this type of girder support 6, it is necessary to tighten or loosen the stopper 11 every time of laying, removing, adjusting the tension force, storing, transporting, and the like. Was troublesome. If the amount of tightening of the stopper 11 is small, if the stopper 11 is loosened, or if the stopper 11 is forgotten to be closed, the screw pipe 8 may jump out of the main pipe 7 and fall off during transportation. Further, after the stopper 11 is tightened, not only the fine adjustment of the cutting beam support 6 cannot be performed, but if it is strongly tightened, a large force is required to loosen it, and it takes time. Further, when the screw tube 8 is extended by rotating the adjusting screw 9 in a state where the stopper 11 is tightened, the screw thread 15 is worn or damaged. Further, the conventional girder support is heavy and difficult to handle because the main member is made of steel.
In order to reduce the weight, a light metal such as aluminum may be used instead of the steel member. However, the strength is insufficient simply by replacing with an aluminum member, and a sufficient pressing force for supporting the sheet pile 4 cannot be obtained.

Accordingly, the present inventors have made the main members aluminum to reduce the weight, to prevent the screw tube itself from falling off and to prevent the screw threads from being worn or damaged by the stopper, and to be able to be used repeatedly for a long period of time. A girder support having excellent properties is introduced in Japanese Patent Application Laid-Open No. Hei 8-246458. However, since the stopper ball is directly pressed against the thread of the threaded pipe by a spring, the stopper ball is difficult to rotate smoothly, and the thread may be cut off by the stopper ball when the stopper ball is crossed. . When the thread is cut, the generated metal debris enters between the stopper ball and the main pipe or screw pipe,
The smooth rotation of the stopper ball is further hindered. Also,
Since the stopper ball is housed in the nut together with the spring and the upper part is closed with bolts, the stopper ball may be loosened during use. The present invention is a further improvement of the previously proposed girder support, in which the stopper ball is housed in a housing of the stopper in a state of being put in a casing, and the housing is urged by a spring to smoothly rotate the stopper ball. An object of the present invention is to provide a girder support that secures and prevents loosening during use.

[0006]

In order to achieve the object, a girder support according to the present invention has an aluminum main pipe, an aluminum screw pipe having one end inserted into the main pipe, and an aluminum threaded pipe. The attached aluminum end plate, the aluminum end plate attached to the other end of the screw pipe, the stopper attached to the peripheral wall of the main pipe at the position where the screw pipe is inserted, and the position inside the stopper The stopper has a housing in which a casing containing a stopper ball fitted between the threads of the threaded pipe is fitted, and the stopper has a housing in which a stopper ball is fitted. A fixing bolt for applying a pressing force via a spring to the housing is screwed to the housing.

A female screw hole penetrating in the thickness direction is formed in the head of the fixing bolt, a wrench hole is formed in the head, and a locking bolt having a sharp lower end is screwed into the female screw hole.
The sharp lower end of the locking bolt is pressed against the top surface of the head of the housing. Thus, the fixing bolt is prevented from rotating with respect to the housing. It is preferable that a recess is formed in the screw thread provided on the screw tube so that the stopper ball hits the thread smoothly, and both circumferential sides of the recess are flat.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A cutting beam support according to the present invention has a structure in which a main pipe 20 and a screw pipe 30 are connected as shown in FIG. 3, and a rear end of the main pipe 20 and a front end of the screw pipe 30. The end plates 40, 50 are bolted to. The connecting screw between the main pipe 20 and the screw pipe 30 has an adjusting screw 60 and a stopper 7.
0 is placed. As shown in FIG. 4 as a state viewed from above (a), a state viewed from the side (b), and a state viewed from the axial direction (c) in FIG. 22, which is produced by heat-treating a 6000 series aluminum extruded material. A flat portion 23 is formed on the outer peripheral surface of the tube 22. A stopper insertion hole 24 is formed in the flat portion 23 near one end, and a through hole 25 for attaching an end plate is formed in a side portion near the other end.

[0009] The screw tube 30 is manufactured by heat-treating an aluminum drawn tube having predetermined mechanical properties.
The thread 31 is formed by rolling over the entire length as shown in a state (a) viewed from above and a state (b) viewed from the side. The thread 31 is provided with an accuracy that does not require machining since threading accuracy can be secured by rolling when maintaining the accuracy of the aluminum drawn tube. The screw tube 30 is provided with a screw stop 32 formed by crushing two threads 31 near one end and a through hole 33 for attaching an end plate at a side near the other end.

The screw 32 is provided so as to restrict the rotation of the adjusting screw 60 (FIG. 3) at this position, and is necessary for the main pipe 20 and the screw pipe 30 to be connected in a straight line without falling off. In FIG. 3, an appropriate position (specifically, 10
0 to 200 mm away). Screw tube 30
The position of the screw 32 in the circumferential direction is not particularly restricted. As shown in FIG. 5C, the thread 31 has a recess 34 having an arcuate cross section in which a stopper ball 71 to be described later is fitted. As shown in FIG. 5D, the concave portions 34 are provided on the plurality of threads 31 in consideration of the length adjustment range of the cutting beam support. Both sides in the circumferential direction of the concave portion 34 are flat surfaces 35 with which the lower end surface of the casing 72 accommodating the stopper ball 71 abuts. Note that a plurality of recesses 34 and flat surfaces 35 may be provided on the thread 34 at equal intervals in the circumferential direction.

The end plates 40, 50 are bolt nuts 41, 5
1 is inserted into the through holes 25 and 33 and fastened,
It is attached to each of the ends of the main pipe 20 and the screw pipe 30 (FIG. 3). As shown in the plan view (a), front view (b), bottom view (c) and side view (d) of FIG. Made of extruded material. The end plate 40 has a flat surface on the outside that comes into contact with the protruding material 5 (FIG. 1).
A plurality of ribs 4 are provided on the web 42 to increase rigidity.
3, 43 are attached. The end of the main pipe 20 is arranged between the ribs 43. On both sides of the web 42, handle insertion openings 44, 44 are provided. Ribs 43, 43
Are formed with connection holes 45 into which bolts 41 for attaching the end plate 40 to the main pipe 20 are inserted. In addition,
Although a plurality of connecting holes 45 are provided in FIG. 6, it is possible to cope with the belly members 5 having different sizes by selecting the connecting holes 45.

The inner diameters of the connection holes 45, 45 and the end plate mounting through-hole 25 are designed to be larger than the outer diameter of the bolt 41. Therefore, when the end plate 40 is connected to the main pipe 20 by the bolt nut 41 inserted into the connection holes 45, 45 and the end plate mounting through-hole 25, the end plate 40 is connected to the bolt nut 41.
7, a swinging motion is performed at a slight angle (specifically, about 1 to 30 degrees) in the vertical direction and the horizontal direction as shown in FIG. Thereby, it becomes possible to make the end plate 40 contact the belly material 5 smoothly. Handle 46,
46 is a handle insertion port 4 provided on both sides of the web 42.
4,44 (FIG. 6e). The handle 46 is formed by bending a surface-treated steel rod, and includes a horizontal portion 46a, an orthogonal portion 46b, and a descending portion 46c as shown in FIG. A pin hole 46d is formed near the lower end of the descending portion 46c. A spring stopper 46e is provided near the upper end of the descending part 46c, and a spring 46f is mounted on the descending part 46c below the spring stopper 46e.

The downward portion 46 c of the handle 46 is inserted into the handle insertion opening 44 of the end plate 40. By pushing down the handle 46 with a pressing force from above, the lower end of the descending portion 46 c projects from the handle insertion opening 44. Therefore, as shown in FIG. 8B, the locking pin 47 is inserted into the pin hole 46d, and the locking pin 47 is provided on the lower end surface of the handle insertion slot 44,
By engaging with 48, the handle 46 is integrated with the end plate 40. In this state, since the descending portion 46c is pulled upward by the restoring force of the spring 46f, the locking pin 47 bites into the pin groove 48, and the mounting state is stabilized. When rotating the handle 46 attached to the end plate 40, a pressing force is applied to the horizontal portion 46 a and the orthogonal portion 46 b to push down the handle 46, and the locking pin 47 is released from the pin groove 48. When the horizontal portion 46a and the orthogonal portion 46b are rotated by 180 degrees in this state, both handles 46, 46 are opened as shown in FIG. 8C. Thus, handle 4
6 and 46 are rotatable so that the handle 4
13 and FIG. 13B, and a state in which the obstructing handles 46 and 46 are opened to bring the end plate 40 into direct contact with the sheet pile (see FIG. 14B). .

The end plate 50 attached to the screw tube 30 also
As shown in a plan view (a), a front view (b), a bottom view (c), and a side view (d) of FIG. 9, it has the same structure as the end plate 40 described above. However, the distance between the ribs 53, 53 is limited by the end plate 4
The ribs 43 are designed to be slightly smaller than the distance between the ribs 43. As shown in the plan view (a), the side view (b), and the view (c) viewed from the axial direction of FIG. 10, the adjustment screw 60 includes a cylindrical portion 61 that is screwed to the screw tube 30. ing. On the inner peripheral surface of the cylindrical portion 61, a female screw 62 that meshes with the thread 31 of the screw tube 30 is formed. A pair of handles 63, 6 protruding outward in the radial direction are provided on the outer peripheral surface of the cylindrical portion 61.
3 are formed. When the adjusting screw 60 is rotated in the direction in contact with the main pipe 20, the screw pipe 30 comes out of the main pipe 20, and the entire length of the girder support becomes longer. Therefore,
By turning the adjusting screw 60, the length of the cutting beam support can be finely adjusted, and the left and right tension force can be set to a desired value.

The adjusting screw 60 is preferably manufactured by surface-treating a material other than aluminum, for example, a cast iron casting. Thus, when a compressive force is applied to the cutting beam support from the left and right groove walls 3 and 3 (FIG. 1), the female screw 62 of the adjusting screw 60 and the screw thread 31 of the screw pipe 30 are firmly engaged. At this time, if the adjustment screw 60 is made of aluminum, the mutual screw bites due to contact with the screw tube 30 of the same material, and the adjustment screw 60 cannot be rotated. On the other hand, in the adjusting screw 60 made of cast iron casting, the female screw 62 is
In order to slightly cut off 1, the adjusting screw 60 can be smoothly rotated to remove the girder support. In that the thread 31 of the thread tube 30 is not bitten, in addition to the cast iron casting,
A dissimilar metal such as stainless steel other than an aluminum alloy can be used as the material of the adjusting screw 60.

As shown in FIG. 11A, a stopper 72 is inserted into a housing 73 containing a stopper ball 71 in a housing 73, and the housing 73 is inserted into a stopper insertion port 24 provided in the main pipe 20 via a washer 74. Screwed. The main constituent member of the stopper 70 is preferably made of stainless steel in consideration of corrosion due to a potential difference from an aluminum alloy. The stopper ball 71 has a diameter slightly larger than the pitch of the thread 31 of the thread tube 30. The casing 72 includes a large-diameter head 72a as shown in FIG. 11B, and a ball housing 72b extends to one side from the head 72a. Ball storage section 72
After the stopper ball 71 is accommodated in the partially spherical concave portion formed in b, the end portion 72c of the ball accommodating portion 72b is caulked, so that the stopper ball 71 is prevented from being pulled out of the casing 72. Stopped stopper ball 7
1 is received on the entire surface of the partially spherical concave portion of the ball housing portion 72b, so that smooth rotation is guaranteed.

A stopper insertion hole 24 is provided in the housing 73.
A male screw 73a screwed into the female screw of the casing 72 is engraved on the outer peripheral surface of the lower end (FIG. 11c), and a step portion 73b on which the large-diameter head 72a of the casing 72 is seated is formed on the inner peripheral surface (FIG. 1).
1a). On the upper end surface of the head 73c of the housing 73,
A plurality of locking grooves 73d are formed radially. A spring 75 is inserted into the housing 73 next to the casing 72, and a fixing bolt 76 is further screwed into the housing 73. Spring 75
Has a spring diameter such that the end winding portion makes surface contact with the head 72a of the casing 72. The fixing bolt 76 includes a spring 75
And a male screw 76b meshing with a female screw formed on the inner peripheral surface of the housing 73 has a leg 76a.
It is formed on a part of the line a. Head 7 of fixing bolt 76
6c has a diameter larger than the inner diameter of the housing 73, and an operation groove 76d extending in the diameter direction is formed on the upper surface. The head 7c is attached to the head 76c of the fixing bolt 76.
6c is formed with a female screw hole 76e penetrating in the thickness direction. A wrench hole 77a is formed in the head of the female screw hole 76e, and a locking bolt 77 having a sharp lower end 77b is screwed into the female screw hole 76e.

The main pipe 20 and the screw pipe 30 are arranged so that the center of the stopper insertion hole 24 of the main pipe 20 is located in the thread groove between the concave portions 34 provided on the screw thread 31 of the screw pipe 30. The stopper 70 is screwed. As a result, as shown in FIG.
Between the recesses 34 of the adjacent thread 31 and the recesses 34 of the thread 31. Threads 3 on both sides of the recess 34
1 is provided with the flat surface 35,
Does not interfere with the thread 31. Thereafter, when the fixing bolt 76 is screwed into the housing 73 containing the casing 72 and the spring 75, the lower end of the leg 76 a presses the head 72 a of the casing 72 via the spring 75. As a result, the stopper ball 71 is pressed against the screw groove by the elastic force of the spring 75, and the screw tube 30 does not accidentally fall out of the main tube 20 by its own weight.

The pressing force due to the elastic force of the spring 75 can be adjusted by the screwing amount of the fixing bolt 76. Therefore, the pressing force applied to the stopper ball 71 is adjusted so that the stopper ball 71 cannot get over the recessed portion 34 of the screw thread 31 to the extent that the weight of the cutting support is applied. . Moreover, since the cutting support of the present invention is made of aluminum and lightweight, the pressing force is small, so that the operator can easily expand and contract the cutting support. In this state, a wrench (not shown) is inserted into the wrench hole 77a of the locking bolt 77, the locking bolt 77 is screwed into the female screw hole 76e, and the sharp lower end 77b is fitted into the locking groove 73d of the housing 73. . This allows
The fixing bolt 76 is stopped against the housing 73. Then, the leg 7 of the fixing bolt 76 is
The pressing force by 6a acts on the head 72a of the casing 72, and the stopper ball 71 is positioned between the valleys between the adjacent threads 31. In this state, the positional relationship of the screw pipe 30 with respect to the main pipe 20 is fixed without the stopper ball 71 going over the screw thread 31. In the illustrated example, a radial locking groove 73d is formed in the head 73c.
Is used, but the locking groove 7 is used.
Housing 73 with flat head upper surface without 3d
Similarly, when the sharp lower end 77b of the locking bolt 77 is pressed against the upper surface of the head, the fixing bolt 76 is prevented from rotating with respect to the housing 73.

When the main pipe 20 and the screw pipe 30 are expanded and contracted, one of the main pipe 20 and the screw pipe 30 is fixed, and the other screw pipe 30 or the main pipe 20 is pulled or pushed by a large force. At this time, since the concave portion 34 has a concave shape, the stopper ball 71 does not deviate from the position of the concave portion 34 during expansion and contraction. Further, as shown in FIG. 5D, the recess 34 is formed in a part of the threaded tube 30 in the axial direction, so that the stopper ball 71 and the thread 31 are formed at the end of the recess 34 in the axial direction. As a result, the screw tube 30 is securely prevented from falling off. In a state where the fixing bolt 76 is stopped, the stopper ball 71 is rotatable with a pressing force that can move over the screw thread 31 one by one. Moreover, since the recessed portion 34 is formed in the thread 31 of the threaded pipe 30, a large force is not required for the stopper ball 71 to climb over the thread 31. Therefore, the screw tube 30 can be manually pulled out or inserted from the main tube 20 without crushing the screw thread 31, and the cutting beam stopper can be moved in accordance with the distance between the opposing groove walls 3, 3 (FIG. 1). The length is adjusted. Further, since both sides in the circumferential direction of the concave portion 34 are flat surfaces 35, the lower end of the casing 72 is also prevented from interfering with the thread 31.

At the time of transportation or the like, the screw tube 30 is also prevented from dropping from the main tube 20 by its own weight. At this time, as shown in FIG. 5D, since the concave portion 34 is formed in a part of the threaded tube 30 in the axial direction, the stopper ball 71 is formed at the end of the concave portion 34 with respect to the axial direction. And the screw tube 30 is securely prevented from falling off. However, in order to prevent the screw tube 30 from inadvertently extending from the main tube 20 during handling, it is desirable that the stopper ball 71 be firmly fixed by screwing the fixing bolt 76. As shown in FIG. 13, the cutting beam support of the present embodiment has the handles 46, 56 facing outward and
Is stretched between the sheet piles 4 and 4. The tension force of the girder support is applied to the plurality of sheet piles 4 and 4 via the bellows 5 and 5 to prevent the groove wall 3 from collapsing. Alternatively, as shown in FIG.
Is rotated by 180 degrees, and as shown in FIG.
0 can be used in a state of being directly contacted with the sheet pile 4. In the use form of FIG. 14, the end plate 50 slightly tilts in the vertical and horizontal directions as described with reference to FIG.
, A good contact state is ensured.

[0022]

As described above, according to the cutting beam support of the present invention, the casing containing the stopper ball is inserted into the housing, and the pressing force is applied to the head of the stopper ball by screwing the fixing bolt through the spring. I have. Therefore, the stopper ball rotates more smoothly than the method in which the spring resilience is directly applied to the stopper ball, and the rotation of the stopper ball is not hindered by metal chips generated by scraping of the screw thread. Also, by pressing the sharp lower end of the locking bolt screwed into the fixing bolt against the head of the housing, the fixing bolt is prevented from rotating against the housing, so that a stopper ball is secured between the thread valleys and the screw for the main pipe is secured. There is no inadvertent change in the amount of tube insertion, ie, the length of the girder support.
In addition, the use of a threaded tube with multiple recesses formed along the axial direction can reduce the force required for the stopper ball to climb over the threads, making it easy to adjust the length of the girder support. Is done. Further, since a structure in which the stopper ball is constantly pressed against the thread of the screw tube is employed, it is possible to prevent the screw tube from accidentally falling off the main tube. In addition, when the fixing bolt is screwed into the housing and the stopper ball is pressed against the thread of the threaded pipe, the threaded pipe is firmly integrated with the main pipe, preventing it from dropping out during transportation, and maintaining the necessary tension force in a safe condition. Is obtained.

[Brief description of the drawings]

FIG. 1 shows a groove with a conventional girder support

[Fig. 2] A conventional girder support with a stopper in contact with the thread of the thread tube

FIG. 3 is an overall perspective view of a girder support according to the present invention.

4 shows the main pipe of a girder support according to the invention from above (a), from the side (b) and from the axial direction (c).

5 (a), a side view (b), a partial sectional view (c) and a partial perspective view of the threaded tube of the girder support according to the present invention when viewed from above, (D)

FIG. 6 is a plan view (a), a front view (b), a bottom view (c), a side view (d), and a plan view with a handle inserted (e) of an end plate attached to an end of a main pipe.

FIG. 7 is a view for explaining that the end plate is attached so as to be tiltable.

8 (a) is a perspective view of a handle inserted into the end plate, FIG. 8 (b) is a bottom view of the end plate provided with means for locking the lower end of the handle, and FIG. (C)

FIG. 9 is a plan view (a), a front view (b), a bottom view (c), and a side view (d) of an end plate attached to an end of a screw tube.

FIG. 10 is a plan view (a), a side view (b) and an axial view (c) of an adjusting screw.

11 is a partial sectional view showing the internal structure of a stopper (a), a manufacturing process diagram of a casing containing a stopper ball (b), an exploded perspective view of the stopper (c), and a plan view of an attached state (d).

FIG. 12 is a sectional view showing the relationship between a stopper, a main pipe, and a screw pipe.

[FIG. 13] A state in which a cutting beam support is erected using a belly material.

FIG. 14 shows a state in which the handle is turned over (a) and the end plate is brought into direct contact with the sheet pile (b).

[Explanation of symbols]

1: ground surface 2: excavation groove 3: groove wall 4: sheet pile
5: Uplifting material 20: Main pipe 21: Cylindrical space 22: Tube
23: Flat portion 24: Stopper insertion opening 25: End plate mounting through hole 26: Tapped hole 30: Screw tube 31: Thread 32: Screw fastening
33: Through-hole for attaching an end plate 34: Recess 35:
Flat surface 40, 50: End plate 41: Bolt / nut 42: Web 43, 53: Rib 44: Handle insertion hole 4
5: Connecting hole 46, 56: Handle 47: Locking pin
48: pin groove 46a: horizontal portion 46b: orthogonal portion 46c: descending portion 46d: pin hole 46e: spring stop 46f: spring 60: adjusting screw 61: cylindrical portion 62: female screw 6
3: Handle 70: Stopper 71: Stopper ball 72: Casing 72a: Head 72b: Ball accommodating portion 72c: Crimping end 73: Housing 73a: Male screw 73b: Step 73c: Head 73d: Locking groove 74: Washer 75: Spring 76: Fixing bolt
76a: leg 76b: male screw 76c: head 76d: operation groove 76e: female screw hole 77: locking bolt 77a: wrench hole 77b: sharp lower end

Claims (3)

[Claims] 1. An aluminum main pipe, an aluminum screw pipe having one end fitted into the main pipe, an aluminum end plate attached to an end of the main pipe, and another end of the screw pipe. An end plate made of aluminum, and a stopper attached to a peripheral wall of the main pipe at a position where the screw pipe is inserted,
An adjusting screw screwed into the threaded pipe at a position inside the stopper, wherein the stopper is fitted with a casing containing a stopper ball fitted between the threads of the threaded pipe; An aluminum cutting beam support having a housing, wherein a fixing bolt for applying a pressing force to a head of the casing via a spring is screwed to the housing. 2. A female screw hole which penetrates the head of the fixing bolt in the thickness direction, a wrench hole is formed in the head, and a locking bolt having a sharp lower end is screwed into the female screw hole. 2. The aluminum cutting beam support according to claim 1, wherein a sharp lower end of the locking bolt is pressed against an upper surface of a head of the housing when the screw is screwed into the female screw hole. 3. The aluminum cutting beam support according to claim 1, wherein a concave portion is formed at a position where the stopper ball contacts the thread of the screw tube, and both sides in the circumferential direction of the concave portion are flat.