insert

The insert's right-hand and left-hand thread combination with a conical washer effectively prevents screw loosening due to vibrations, enhancing the reliability and extending maintenance intervals of equipment attached to concrete structures.

JP2026119917APending Publication Date: 2026-07-21JIYAPAN RAIFU
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Patent Information

Authority / Receiving Office
JP · JP
Patent Type
Applications
Current Assignee / Owner
JIYAPAN RAIFU
Filing Date
2025-01-08
Publication Date
2026-07-21

AI Technical Summary

Technical Problem

Existing inserts used to attach equipment to concrete structures experience loosening of screw members due to vibrations, leading to reduced maintenance and inspection intervals.

Method used

The insert design incorporates a combination of right-hand and left-hand threads for the fastening screw member and nut, along with a conical washer to distribute fastening force evenly, preventing loosening under vibration.

Benefits of technology

Prevents loosening of screw members, thereby extending the maintenance and inspection intervals of attached equipment.

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Abstract

The purpose is to prevent the screw threads of the insert from loosening. [Solution] An opening 14 for a housing hole 12 is provided at the tip of the insert body 11 which is embedded in the concrete structure 1, and the housing hole 12 is bottomed out by a bottom wall 18 provided at the base end. A first female thread 19 is formed at the base end of the insert body 11, and a first male thread 21 that screws into the female thread 19 is provided at one end of the fastening screw member 20, and a second female thread 25 provided on a nut 26 is screwed into a second male thread 24 provided at the other end of the fastening screw member 20, and the equipment is fastened to the concrete structure 1 by the nut 26. One of the first male thread 21 and the second male thread 24 is a right-hand thread, and the other is a left-hand thread.
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Description

Technical Field

[0001] The present invention relates to an insert embedded in a concrete structure for attaching laying equipment such as processing machines to concrete structures such as concrete slabs.

Background Art

[0002] An insert, which is a type of concrete anchor, is used to attach processing machines such as presses, laser cutting machines, and lathes to a concrete slab, which is a concrete floor slab. The insert is also used to attach suspension objects such as drain pipes, rain gutters, and work platforms to concrete bridges. Furthermore, the insert is used to fix accessory devices such as exhaust jet fans and exhaust ducts to the inner surface of a concrete tunnel.

[0003] An insert for attaching laying equipment such as the above-described processing machines, suspension objects, and accessory devices to a concrete structure is embedded in the concrete structure as a type of anchor member.

[0004] Patent Document 1 discloses an insert for attaching a pipe, which is laying equipment, to a wall of a building such as a concrete building. The insert has an insert body embedded in the wall of the building, and by fastening a fixture attached to the pipe to the insert body with a fastening screw member, the pipe is attached to the wall, and the fastening screw member is embedded in the building together with the insert body.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] When suspended structures or other laid equipment vibrates, that vibration is transmitted to the mounting fixtures attached to the equipment. Therefore, if the equipment has been attached to a concrete structure for a long period of time, it is expected that the screw members of the inserts will loosen due to vibrations in the mounting fixtures. For this reason, the maintenance and inspection period for equipment attached to concrete structures cannot be extended. If the loosening of the screw members can be prevented even when the equipment vibrates, the reliability of the inserts can be increased, and the maintenance and inspection period for the equipment can be extended.

[0007] The present invention has been made in light of the above-mentioned technical background, and aims to provide a technology that can prevent the loosening of the screw member of the insert. [Means for solving the problem]

[0008] To solve the above problems, the insert of the present invention as described in claim 1 comprises an insert body having a bottomed receiving hole with an opening at its tip and a bottom surface at its base end, which is embedded in a concrete structure; a fastening screw member having a first male screw at one end that screws into a first female screw provided at the base end of the insert body; and a nut having a second female screw at the other end of the fastening screw member that screws into a second male screw, wherein one of the first male screw and the second male screw is a right-hand thread and the other is a left-hand thread.

[0009] Furthermore, the present invention as described in claim 2 is characterized in that, in the invention described in claim 1 above, an engaging portion for which a rotary tool engages is provided at the other end of the fastening screw member.

[0010] Furthermore, the present invention as described in claim 3 is characterized in that, in the invention as described in claim 2, the engaging portion has two engaging surfaces that are parallel to each other.

[0011] Furthermore, the present invention as described in claim 4 is characterized in that, in the invention described in claim 1, the first male screw is a right-hand thread and the second male screw is a left-hand thread.

[0012] The present invention as described in claim 5 is characterized in that, in the invention as described in claim 1, a washer is disposed between the fixing member attached to the laying equipment and the nut, and the fastening force of the nut is transmitted to the fixing member via the washer.

[0013] The present invention as described in claim 6 is the insert according to claim 5, characterized in that the washer is a conical washer in which the outer diameter of the other end face facing the fixing member is larger than the outer diameter of the one end face facing the nut. [Effects of the Invention]

[0014] According to the present invention of claim 1, the insert body has a bottomed receiving hole formed at its base end, and one of the first male thread of the fastening screw member that is screwed into the first female thread of the insert body and the second male thread of the fastening screw member that is screwed into the second female thread of the nut is a right-hand thread and the other is a left-hand thread, so that the insert body, the fastening screw member and the nut do not loosen from each other due to vibration or the like.

[0015] According to the present invention as described in claim 2, the fastening screw member is provided with an engagement portion into which a rotary tool engages, and by rotating the fastening screw member using the rotary tool, the fastening screw member can be manually screwed into the insert body.

[0016] According to the present invention as described in claim 3, the engaging portion has two engaging surfaces that are parallel to each other, and the fastening screw member can be rotated with a rotating tool such as a wrench.

[0017] According to the present invention as described in claim 4, by making the first male screw a right-hand thread, mass-produced products can be used as the insert body.

[0018] According to the present invention as described in claim 5, the fastening force of the nut can be transmitted to the fixture via the washer.

[0019] According to the present invention described in claim 6, the fastening force of the nut can be evenly dispersed by the conical washer and transmitted to the fixture, thereby preventing the nut from loosening.

Brief Description of the Drawings

[0020] [Figure 1] It is a cross-sectional view showing an insert according to an embodiment of the present invention. (a) is a cross-sectional view showing an insert embedded in a concrete slab for attaching a processing machine such as a press to the concrete slab, (b) is a cross-sectional view showing an insert embedded in a concrete bridge for attaching a suspension such as a drain pipe to the bridge, and (c) is a cross-sectional view showing an insert attached to a tunnel for attaching an accessory device such as an exhaust duct to the inner surface of a concrete tunnel. [Figure 2] It is a perspective view showing a mounting member and an insert attached to a processing machine as shown in Fig. 1(a). [Figure 3] It is a perspective view showing a mounting member and an insert attached to a suspension as shown in Fig. 1(b). [Figure 4] It is a perspective view showing a mounting member and an insert attached to an accessory device as shown in Fig. 1(c). [Figure 5] It is an exploded cross-sectional view of an insert according to an embodiment of the present invention. [Figure 6] It is a cross-sectional view of the insert in a state where the laying equipment is attached to the concrete structure. [Figure 7] It is a plan view of Fig. 6.

Modes for Carrying Out the Invention

[0021] Hereinafter, an embodiment as an example of the present invention will be described in detail based on the drawings. In the drawings for explaining the embodiment, the same reference numerals are generally given to the same components, and the repeated description thereof will be omitted.

[0022] As shown in Figures 1(a) and 2, the mounting fixture 2 for attaching a processing machine, a type of laying equipment, to the upper surface of a concrete slab 1a, which is a concrete structure 1 (Figure 6), has a cylindrical member 3 to which the processing machine is attached, and two leg pieces 4 fixed to the cylindrical member 3. Each leg piece 4 has a fixing portion 4a that is welded to the cylindrical member 3, and a fastening portion 4b that is bent at a right angle to the fixing portion 4a, and the fastening portion 4b is fastened to the concrete slab 1a by two inserts 10 embedded in the concrete slab 1a.

[0023] As shown in Figures 1(b) and 3, the mounting device 2 for attaching a suspension device, which is a type of installation equipment, to the side surface of a concrete bridge pier 1b has a fixing part 5a to which the suspension device is attached, and a fastening part 5b that is twisted perpendicular to the fixing part 5a. The fixing part 5a has a screw hole 5c for attaching the suspension device, and the fastening part 5b is fastened to the bridge pier 1b by an insert 10 embedded in the bridge pier.

[0024] As shown in Figures 1(c) and 4, the installation member 2 for attaching an auxiliary device, which is a type of laying equipment, to the inner surface of the tunnel 1c has a fixing part 7a to which the auxiliary device is installed by bolts 6, and a fastening part 7b to which the fixing part 7a is welded on the outer surface, and the fastening part 7b is fastened to the tunnel 1c by two inserts 10 embedded in the tunnel 1c.

[0025] Figures 1(a) and 1(c) show two inserts 10 embedded in a concrete structure, and Figure 1(b) shows one insert embedded in a concrete structure.

[0026] Figure 5 is an exploded cross-sectional view of the insert 10 according to one embodiment of the present invention shown in Figures 1 to 4, Figure 6 is a cross-sectional view of the insert when the laying equipment is attached to the concrete structure 1, and Figure 7 is a plan view of Figure 6.

[0027] The insert 10 has an insert body 11 that is embedded in a concrete structure 1, and the insert body 11 is made of a ceramic such as alumina. A housing hole 12 is formed in the insert body 11, and the housing hole 12 is open to the outside through an opening 14 provided on the tip surface 13 of the insert body 11.

[0028] The tip side of the insert body 11 is a straight section 15 with a nearly constant outer diameter, and the base side has a bulging section 16 with a larger diameter than the straight section 15, with a constricted section 17 formed between the bulging section 16 and the straight section 15. Due to the bulging section 16 and the constricted section 17, the insert body 11 bites into the concrete structure 1 and is firmly embedded.

[0029] The insert body 11 is attached to the formwork in advance when constructing the concrete structure 1, and is embedded in the concrete structure 1 by pouring concrete into the formwork. When the insert body 11 is embedded, the tip surface 13 is exposed on the outer surface of the concrete structure 1.

[0030] When insert 10 is used to attach a processing machine to a concrete slab 1a, as shown in Figures 1(a) and 2, the insert body 11 is embedded in the concrete slab 1a. When insert 10 is used to attach a suspension to a bridge, as shown in Figures 1(b) and 3, the insert body 11 is embedded in the bridge 1b. Furthermore, when insert 10 is used to attach an accessory to a tunnel, as shown in Figures 1(c) and 4, the insert body 11 is embedded in the tunnel.

[0031] The base end of the insert body 11 is provided with a bottom wall 18 to close the housing hole 12. When the insert body 11 is embedded in a concrete structure 1 such as a concrete slab 1a, the bottom wall 18 prevents the concrete poured into the formwork from flowing into the housing hole 12.

[0032] The base end of the insert body 11 is provided with a female thread 19 as the first female thread. The insert 10 has a fastening screw member 20 that is incorporated into the housing hole 12 of the insert body 11. One end of the fastening screw member 20 is provided with a male thread 21 that screws into the female thread 19, i.e., is screw-connected, as the first male thread.

[0033] The male screw 21 is a right-hand thread. When the fastening screw member 20 is rotated to the right when viewed from the axial direction, the fastening screw member 20 moves in a direction that enters the female screw 19, and when rotated in the opposite direction, it moves in a direction that exits the female screw 19. The male screw 21 is a trapezoidal screw with a trapezoidal thread shape and is a single-start screw.

[0034] An engagement portion 22, into which a rotary tool such as a wrench engages, is provided at the other end of the fastening screw member 20. By rotating the fastening screw member 20 with the rotary tool, the male screw 21 is screwed into the female screw 19 of the insert body 11. As shown in Figure 7, the engagement portion 22 has two mutually parallel engagement surfaces 23, into which the rotary tool engages. The cross-sectional shape of the engagement portion 22 may be a square with four engagement surfaces 23, or a regular hexagon with six engagement surfaces 23.

[0035] At the other end of the fastening screw member 20, a male screw 24 is provided as a second male screw, positioned axially inward from the engaging portion 22. A nut 26, which has a female screw 25 that screws onto the male screw 24, is attached to the fastening screw member 20. By screwing the female screw 25 onto the male screw 24 and attaching the nut 26 to the fastening screw member 20, the installation equipment such as processing machinery is fastened to the concrete structure 1.

[0036] The insert 10 comprises an insert body 11, a fastening screw member 20, and a nut 26. The fastening screw member 20 is incorporated into the insert body 11, which is pre-embedded in the concrete structure 1, and is embedded in the concrete structure 1 together with the insert body 11.

[0037] The male screw 24 is a left-hand thread. When the nut 26 is rotated counterclockwise when viewed from the axial direction, the nut 26 moves in a direction toward the male screw 24, and when rotated in the opposite direction, it moves toward the direction toward disengaging from the male screw 24. The male screw 24, like the male screw 21, is a trapezoidal screw with a trapezoidal thread shape and is a single-start screw.

[0038] The fastening screw member 20 is pre-inserted into the housing hole 12 of the insert body 11 so that the male thread 21 is screwed into the female thread 19.

[0039] In Figure 6, a concrete structure such as a concrete slab 1a is indicated by reference numeral 1, and the mounting fixture 2 attached to the laying equipment is shown fastened with a nut 26.

[0040] When attaching the laying equipment to the concrete structure 1 using the insert 10, as shown in Figure 6, the mounting fixture 2 attached to the laying equipment is abutted against the outer surface of the concrete structure 1 and against the tip surface 13 of the insert body 11, and the female thread 25 of the nut 26 is screwed onto the male thread 24 of the fastening screw member 20 to assemble the nut 26 to the fastening screw member 20.

[0041] A conical washer 28 is fitted between the nut 26 and the fixture 2, and the fastening force of the nut 26 is transmitted to the threaded connection surface of the male screw 24 and the female screw 25, as well as to the fixture 2 via the conical washer 28.

[0042] The outer surface of the conical washer 28 abuts against the nut 26, and the inner surface of the conical washer 28 abuts against the tip surface 13 of the insert body 11 via the mounting fixture 2. Therefore, the fastening force of the nut 26 is transmitted to the tip surface 13 via the conical washer 28 and the mounting fixture 2, and the mounting fixture 2 of the installation equipment is firmly attached to the insert 10.

[0043] Since the conical washer 28 has a larger outer diameter on the other end face facing the fixture 2 than on the one end face facing the nut 26, the axial fastening force of the nut 26 can be evenly distributed radially outward, thereby preventing the nut 26 from loosening.

[0044] With the installation equipment attached to the insert 10, the male thread 21 of the fastening screw member 20, which is a right-hand thread, is screwed into the female thread 19 of the insert body 11, and the male thread 24, which is a left-hand thread, is screwed into the female thread 25 of the nut 26. Therefore, even if the nut 26, which is a left-hand thread, is subjected to an external force that loosens the fastening screw member 20, i.e., an external force in the direction of right rotation, due to vibrations of the installation fixture 2 of the installation equipment or the concrete structure 1, that external force will advance the male thread 21, which is a right-hand thread, of the fastening screw member 20 relative to the insert body 11.

[0045] This ensures that the fastening screw member 20 and nut 26 do not loosen even if the installation equipment vibrates.

[0046] Male screw 21 is a right-hand thread and male screw 24 is a left-hand thread. However, even if male screw 21 is a left-hand thread and male screw 24 is a right-hand thread, loosening of the screws can be reliably prevented. In other words, if both screws are threaded in opposite directions, and one of the two male screws 21 and 24 is a right-hand thread and the other is a left-hand thread, the combination of right-hand and left-hand threads can prevent loosening of the screws and extend the maintenance and inspection period of the installed equipment.

[0047] Male screws 21 and 24 have the same outer diameter and pitch, but by making the outer diameters and pitches of both male screws different, it is possible to prevent them from rotating together in the same direction, thereby more reliably preventing the nut 26 and fastening screw member 20 from loosening.

[0048] The present inventors have described the invention in detail based on embodiments, but the embodiments disclosed herein are illustrative in all respects and are not limited to the disclosed technology. That is, the technical scope of the present invention should not be interpreted restrictively based on the description of the embodiments above, but rather in accordance with the claims, and includes the equivalent technology of the claimed technology and all modifications that do not depart from the gist of the claims.

[0049] For example, the installation equipment attached to the concrete structure 1 is not limited to the processing machines and the like described above, but can be anything that can be attached to the insert 10 by a screw member. Furthermore, the male screws 21, 24 and female screws 19, 25 are not limited to trapezoidal screws with a trapezoidal cross-sectional shape of the thread, but may be triangular screws with a triangular cross-sectional shape of the thread, square screws with a cross-sectional shape of the thread close to the positive direction, or sawtooth screws that combine square screws and triangular screws. Moreover, round screws with a rounded cross-section of the thread may also be used.

[0050] Furthermore, although the insert body 11 is made of ceramics in this embodiment, it may be made of a material other than ceramics, such as stainless steel, iron, aluminum, or other metals. [Industrial applicability]

[0051] The insert of the present invention has an insert body that is embedded in concrete structures such as concrete slabs and concrete bridge piers, and can be used to attach laying equipment to concrete structures by screw members that are screw-connected to the insert body. [Explanation of Symbols]

[0052] 1. Concrete structures 1a Concrete slab 1b Bridge pier 1c Tunnel 2. Mounting hardware 3. Cylindrical member 4 leg pieces 4a Fixed part 4b Fastening part 5a Fixed part 5b Fastening section 6 volts 7a Fixed part 7b Fastening section 10 inserts 11 Insert body 12 containment holes 13 Tip surface 14 Opening 15. Straight section 16 Bulge 17. Constricted area 18 Bottom wall 19 Female thread (first female thread) 20 Fastening screw member 21 Male screw (first male screw) 22 Engaging part 23 Engagement surface 24 Male thread (second male thread) 25 Female thread (second female thread) 26 nuts 27 Female thread groove 28 Washer

Claims

1. An insert body is embedded in a concrete structure, having an opening at the tip and a bottom surface at the base, forming a bottomed receiving hole. A fastening screw member having a first male screw at one end that screws into a first female screw provided at the base end of the insert body, The fastening screw member has a nut with a second female thread that screws onto a second male thread provided at the other end of the screw, An insert characterized in that one of the first male screw and the second male screw is a right-hand thread, and the other is a left-hand thread.

2. The insert according to claim 1, characterized in that the other end of the fastening screw member is provided with an engaging portion for engaging with a rotary tool.

3. The insert according to claim 2, characterized in that the engaging portion has two engaging surfaces that are parallel to each other.

4. The insert according to claim 1, characterized in that the first male thread is a right-hand thread and the second male thread is a left-hand thread.

5. The insert according to claim 1, further comprising a washer positioned between a fixing member attached to the laying equipment and the nut, wherein the fastening force of the nut is transmitted to the fixing member via the washer.

6. The insert according to claim 5, characterized in that the washer is a conical washer in which the outer diameter of the other end face facing the fixing member is larger than the outer diameter of the one end face facing the nut.