Expansion nut

Abstract

The utility model patent discloses an expansion nut, which is composed of two parts: a cone nut and an inner cone sleeve. The cone nut is a nut with internal threads in a truncated cone; the inner cone sleeve is an open sleeve of the inner cone hole, and has a semi-through slot for easy expansion. The expansion is achieved by squeezing the outer cone with the inner cone, and the outer cone squeezes the concrete installation hole to form an integral structure. When using the expansion nut of this structure, even if the sports equipment is removed, no exposed screws will be left in the sports field, which completely eliminates the hidden dangers of unsafety brought by athletes during training and competition. It can also be used for sports equipment made of non-metallic materials such as soft wood, plastic, bakelite and composite board, and the expansion nut can be used to replace the internal thread in the parts that cannot be tapped.

Description

Technical field:

[0001] The utility model relates to a fastener, in particular to an expansion nut. Background technology:

[0002] In the sports world, it is common to use expansion screws to connect to the ground to fix sports equipment, such as the horizontal bar, uneven bars, pommel horse, vaulting horse, etc. in gymnastics. After removing the sports equipment, the screws of the expansion screws are exposed. Although the screws are loose, they are difficult to remove, which brings safety hazards to athletes during training and competition. In addition, it can be seen everywhere on the walls of outdoor buildings. Due to the dismantling of equipment installed on the exterior wall, the traces of the screws left by the expansion screws that cannot be removed are left. Therefore, how to remove the screws of expansion screws is a problem worth studying. Summary of the invention:

[0003] The utility model provides an expansion nut which adopts a shear-shaped slope to promote expansion to generate a frictional holding force and achieve an anchoring effect.

[0004] Technical problems to be solved:

[0005] Expansion screws can be divided into tension-compression expansion and top-pressure expansion structures. Both of them have a truncated cone at the end of the screw, and rely on the outer oblique cone at the end of the screw to squeeze, and the inner cone at the end of the sleeve to the bottom of the concrete wall hole, and the expansion and squeezing interference fit is fixed; and there is a large amount of shaky gap between the screw and the sleeve, and even the phenomenon that the screw cannot be tightened when the nut is turned, which also brings difficulties to removal. Even if a cutting machine is used to destructively cut off the exposed screw, shaking the exposed screw can easily break the cutting blade, causing injuries. The utility model fundamentally and thoroughly solves the technical problem of leaving no exposed screw in the removed expansion screws on the premise of retaining the characteristics of the expansion screws.

[0006] Technical solutions adopted:

[0007] The expansion nut is characterized in that it is composed of a conical nut and an inner conical sleeve, the outer shape of the conical nut is a nut with internal threads in a truncated cone; the outer shape of the inner conical sleeve is a cylinder, the inner hole is an inner conical through-hole open sleeve matched with the outer cone of the truncated cone, and a semi-through open groove is provided from the large end to the small end of the inner conical hole for easy axial expansion. After the expansion nut is pre-fixed and installed by a short bolt, when the bolt is tightened with a wrench to install the sports equipment, the outer cone of the conical nut squeezes the inner cone of the inner conical sleeve, forcing the semi-through open groove to expand evenly under force, and while the outer circle of the inner conical sleeve squeezes the mounting hole, the inner and outer tapers cooperate to self-lock, and the inner and outer circles squeeze the interference anchoring anti-loosening structure, which completely eliminates the effect of shaking gap after expansion.

[0008] Further explanation:

[0009] 1) The engagement length between the conical nut and the inner conical sleeve and the engagement depth of the concrete installation hole are the key to determining the tensile and shear stability after expansion. Generally, the embedding depth of the expansion nut is four times the diameter of the fixing screw.

[0010] 2) Control the diameter of the expansion nut installation hole, which must be within the expansion range. The higher the hardness of the connecting material, the stronger the tensile strength after tightening and installation.

[0011] Anti-loosening mechanism:

[0012] In order to increase the installation speed, the large end of the inner cone hole of the sleeve is aligned with the small end of the outer cone of the cone nut, and then the expansion nut is screwed into the short bolt with the washer, and the bolt head is hit with a hammer to press the expansion nut into the concrete installation hole. The inner cone sleeve is flush with the wall (ground) concrete. Because the washer blocks the inner cone sleeve, when the bolt is screwed with a wrench, the cone nut under tension squeezes the inner cone of the inner cone sleeve with the outer cone, forcing the half-through opening groove to expand evenly. While the force is transmitted to the outer circular wall of the inner cone sleeve to squeeze the inner circular wall of the concrete installation hole, the inner and outer tapers are self-locking, and the inner and outer circles are squeezed to interference, which completely eliminates the shaking gap that may occur after expansion. After anchoring and installing the expansion nut, remove the short bolt, and then insert the screw of the bolt to be installed into the spring washer and washer, insert it into the installation hole of the sports equipment, and screw it into the inner threaded hole of the cone nut of the expansion nut. When tightening the bolt with a wrench, the outer cone of the conical nut continues to squeeze the inner cone of the inner cone sleeve, causing the outer circle of the inner cone sleeve to squeeze the concrete mounting hole for the second time, ensuring that the inner and outer cones and the inner and outer circles are completely and thoroughly meshed as a whole, and the open groove and the semi-through open groove of the inner cone sleeve expand, controlling the expansion nut from easily rotating between the concrete mounting hole.

[0013] The beneficial effects of the utility model are:

[0014] Improve the tensile and shear stability of expansion screws, leave expansion nuts flush with the building when dismantling sports equipment without affecting the appearance, eliminate exposed screws that should not be left, and eliminate hidden dangers that may cause casualties in sports venues; it can also be used for sports equipment with softer textures, such as wood floors, plastics, bakelite and composite boards in free gymnastics venues. Non-metallic materials cannot be tapped for connection, and expansion nuts can be used instead of internal threads for beneficial effects. Description of the drawings:

[0015] Figure 1 It is the front view of the cone nut;

[0016] Figure 2 It is the right side view of the cone nut;

[0017] Figure 3 It is the left view of the inner cone casing;

[0018] Figure 4 It is the main view of the inner cone casing;

[0019] Figure 5 It is the main view of the expansion nut;

[0020] Figure 6 Front view of step one in preparation for installing the expansion nut;

[0021] Figure 7 To remove the short bolts and washers, the expansion nuts are flush with the wall (ground) surface. Front view of step 2;

[0022] Figure 8 The analysis view of step three for installing the expansion nut inner cone sleeve expansion and the meshing area F of the wall (ground) hole;

[0023] Fig. 9 This is the front view of the expansion nut installed on wood (plastic);

[0024] Fig.10 This is the front view of the expansion nut installed on the composite board (bakelite board);

[0025] Fig.11 This is the main view of the tension and compression type expansion screw;

[0026] Fig.12 This is the front view of the top pressure expansion screw;

[0027] Fig.13 This is an analytical view of the common feature of expansion screws, the tapered expansion at the tail and the engagement area F with the wall (ground) hole.

[0028] Figures 1 to 13 middle

[0029] 1: Cone nut;

[0030] 2: Inner cone casing;

[0031] 3: Bolts;

[0032] 4: Spring washer (disc spring);

[0033] 5: Washer;

[0034] 6: Connectors (sports equipment);

[0035] 7: Concrete wall (ground);

[0036] 8: Wood (plastic);

[0037] 9: Composite board (bakelite board);

[0038] 10: gap;

[0039] F: The tensile area meshing with the concrete wall (ground). Specific implementation method:

[0040] The utility model is specifically described as follows in conjunction with the accompanying drawings:

[0041] Embodiment 1:

[0042] like Figure 1-Figure 4 The expansion nut shown is composed of two parts: a cone nut 1 and an inner cone sleeve 2.

[0043] Embodiment 2:

[0044] like Figure 5 The expansion nut shown in the figure is pre-assembled by inserting and gluing the inner cone hole of the inner cone sleeve 2 into the outer cone of the cone nut 1 with a double-sided adhesive tape. Figure 5 .

[0045] Embodiment 3:

[0046] like Figure 6 The expansion nut shown in the figure has the following installation steps: use an electric hammer to drill a hole in the concrete wall (ground), insert a washer 5 that is larger than the outer diameter of the inner cone sleeve 2, and screw a short bolt 3 whose length is ≤ that of the inner cone sleeve 2 into the cone nut 1. After assembly, use a hammer to impact the bolt head 3 and drive it into the installation hole of the concrete 7. In the process of tightening the bolt 3 with a wrench, since the washer 5 prevents the inner cone sleeve 2 from being flush with the concrete wall (ground), the short bolt 3 pulls back the cone nut 1, squeezes the inner cone sleeve 2 to expand, and the outer circular wall of the sleeve 2 is completely meshed with the wall of the concrete installation hole. Figure 6 .

[0047] Embodiment 4:

[0048] like Figure 7 Expansion nut shown, installation step 2: remove the expansion nut with short bolt 3 and washer 5 Figure 5 Flush with concrete wall (ground) surface 7 Figure 7 .

[0049] Embodiment 5:

[0050] like Figure 8 The expansion nut shown in the figure has the third installation step: insert the screw of the bolt 3 into the spring washer 4 and the washer 5, insert it into the mounting hole of the connector 6, screw it into the cone nut inner thread of the expansion nut 1 that has been installed and fastened in the hole of the concrete wall (ground), and then tighten the bolt 3 with a wrench. The outer cone wall of the cone nut 1 continues to squeeze the inner cone wall of the inner cone sleeve 2, so that the outer circle wall of the inner cone sleeve 2 squeezes the mounting hole of the concrete 7 for the second time, ensuring that the inner and outer cones are completely and reliably meshed with the inner and outer circles. Figure 8 The opening groove of the inner cone sleeve 2 and the half-through opening groove expand to control the expansion nut 1 to prevent it from easily rotating with the concrete installation hole to prevent it from loosening.

[0051] Embodiment 6:

[0052] like Figure 7 , Figure 8 To disassemble the expansion nut shown, just use a wrench to reverse the bolt 3 and remove it. Figure 8 , leaving the expansion nut flush with the concrete 7 wall (ground) surface Figure 7 , it neither hurts anyone nor affects the aesthetics of the picture.

[0053] Embodiment 7:

[0054] like Fig. 9 The expansion nut shown is used to connect sports equipment on a wood (plastic) 8 structure. First, shorten the length of the conical nut 1 and the inner conical sleeve 2 to ≤ the pre-drilled depth, then bury the expansion nut in the pre-drilled hole, tighten the cylindrical head hexagonal bolt 3 with an external hexagonal wrench, pull back the outer cone of the conical nut 1 to squeeze the inner cone of the inner conical sleeve 2 to expand outward, and the outer circle of the sleeve 2 and the mounting hole of the wood (plastic) 8 are completely engaged, interference anchored and self-locking, which plays the role of replacing the internal thread.

[0055] Embodiment 8:

[0056] like Fig.10 The expansion nut shown is used to connect sports equipment on a composite board (bakelite board) 9 structure. First, the length of the cone nut 1 and the inner cone sleeve 2 is shortened to the depth of the countersunk hole. Figure 5 , then bury the expansion nut into the countersunk hole, tighten the bolt 3 with a wrench, pull back the outer cone of the conical nut 1 to squeeze the inner cone of the inner cone sleeve 2 to expand outward, and the outer circle of the sleeve 2 and the mounting hole of the composite board (bakelite) 9 are completely engaged with the interference anchoring self-locking, which plays the role of replacing the internal thread.

[0057] Embodiment 9:

[0058] like Fig.11 , Fig.12 , Fig.13 The expansion screws shown are two different structures of bolt pull-back compression expansion screws Fig.11 With bolt top pressure expansion screw Fig.12 The outer oblique cone angle of the screw tail end is used to squeeze (pull) the F sleeve in the concrete wall hole to expand and mesh with the anchor. Fig.13 , there is a lot of room for movement.

[0059] Embodiment 10:

[0060] like Figure 8 and Figure 11-13 The expansion nut shown is different from the expansion screw; the expansion nut is engaged with the concrete installation hole 7 by screwing the external thread into the internal thread and pulling it back, the outer conical wall 1 squeezes the inner conical wall 2 to expand, and the outer circular wall of the sleeve is completely engaged with the inner circular wall of the concrete installation hole 7, and there is no gap for shaking. Figure 8There are two different structures of bolt pull-back expansion screws on the market. Fig.11 With bolt top pressure expansion screw Fig.12 The cone at the end of the screw rod is an oblique cone, which squeezes the end of the F open round sleeve at the bottom of the concrete 7 installation hole and expands at an oblique angle, which is transmitted to the outer circle of the sleeve and the inner circle wall of the concrete 7 installation hole, forming the strongest extrusion force on the end of the sleeve, which gradually decreases forward until it reaches zero at the root of the truncated cone, resulting in uneven extrusion force at an oblique angle between the sleeve and the bottom of the concrete 7 installation hole, and a large amount of shaking gap 10 exists between the rear end of the screw rod and the sleeve and the concrete 7 installation hole. Figure 11-13 .

[0061] The above examples do not limit the present invention in any way, and any technical solutions obtained by equivalent replacement or equivalent transformation shall fall within the protection scope of the present invention.

Claims

1. Expansion nut, characterized in that: It consists of a conical nut and an inner conical sleeve. The outer shape of the conical nut is a nut with internal threads in a truncated cone. The outer shape of the inner conical sleeve is a cylinder, and the inner hole is an inner conical through-hole open sleeve that matches the outer cone of the truncated cone. From the large end to the small end of the inner conical hole, a semi-through open groove is provided to facilitate axial expansion. After the expansion nut is pre-fixed and installed by a short bolt, when the bolt is tightened with a wrench to install the sports equipment, the outer cone of the conical nut squeezes the inner cone of the inner conical sleeve, forcing the semi-through open groove to expand evenly under force. While the outer circle of the inner conical sleeve squeezes the mounting hole, the inner and outer tapers cooperate to self-lock, and the inner and outer circles squeeze the interference anchor to prevent loosening, which completely eliminates the effect of shaking gap after expansion.

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