Novel internal expansion screw

Abstract

The utility model relates to the field of expansion screws, and discloses a novel internal expansion screw which comprises an expansion pipe, a threaded groove is formed in the inner wall of the upper half portion of the expansion pipe, a conical cavity is formed in the lower half portion of the expansion pipe, a plurality of preformed holes are formed in the lower half portion of the outer wall of the expansion pipe, and barbs are fixedly connected to the inner bottom walls of the preformed holes. The bottom of the outer wall of the expansion pipe is fixedly connected with a plurality of side wings. The bolt is in threaded fit with the expansion pipe. When a pipeline support is installed, installation time is greatly shortened, installation accidents are reduced, anchoring strength is higher, drill holes cannot be damaged, and after the internal expansion screw is fastened, the problems that the expansion screw rotates and cannot be locked tightly are thoroughly solved through the structural characteristics of the triangular side wings and the petal-shaped barbs at the front end of the internal expansion screw.

Description

Technical Field

[0001] This utility model relates to the field of expansion bolts, and specifically to a new type of internal expansion bolt. Background Art

[0002] At present, most of the internal expansion bolts are explosion - pressed expansion bolts. Such expansion bolts consist of two parts: an outer sleeve and an expansion bolt. When using an explosion - pressed expansion bolt, it is necessary to use a drill rod and a hammer to hammer the expansion bolt forward, and forcefully expand the outer sleeve. In this process, there are problems such as damaging the drill hole and even damaging the wall. Due to the destructive force generated when hammering the internal expansion bolt and the limited compressive strength of the red brick wall, this type of explosion - pressed expansion bolt can only be used in concrete.

[0003] Moreover, for the explosion - pressed expansion bolt, the expansion force of the outer sleeve is insufficient. Since the opening size of its expansion end is determined by whether the expansion bolt is hammered in, and whether the expansion bolt is hammered in is determined by the magnitude of the hammering force, in the installation of pipeline supports, due to the low anchoring strength, the expansion bolts often fall off, resulting in property losses. Content of the Utility Model

[0004] In order to overcome the above - mentioned deficiencies, this utility model provides a new type of internal expansion bolt.

[0005] The technical solution adopted by this utility model is as follows:

[0006] A new type of internal expansion bolt includes an expansion tube. Threaded grooves are provided on the inner wall of the upper half of the expansion tube, a conical cavity is provided in the lower half of the expansion tube, a plurality of reserved holes are provided on the outer wall of the lower half of the expansion tube, barbs are fixedly connected to the inner bottom wall of the reserved holes, and several wings are fixedly connected to the bottom of the outer wall of the expansion tube.

[0007] The barbs are in the shape of petals, and the number of barbs is three or four. The reserved holes are located at the bottom end of the internal expansion bolt, the tips of the barbs face the top, and the bottom ends of the barbs are connected to the expansion tube.

[0008] The conical cavity starts from the cut - off point of the threaded groove on the inner wall of the expansion tube and extends to the top of the reserved hole.

[0009] The wings are in the shape of triangular pyramids and are located at the bottommost of the outer wall of the expansion tube.

[0010] Advantages of this Utility Model

[0011] When installing the pipeline support, this utility model greatly shortens the installation time, reduces installation accidents, has a higher anchoring strength, and does not damage the drill hole. After the internal expansion bolt of this utility model is fastened, due to the structural characteristics of the triangular wings and petal - shaped barbs at its front end, the problem of the expansion bolt spinning and not being tightened is completely solved. Description of the Drawings

[0012] Figure 1It is a schematic structural diagram of the utility model;

[0013] Figure 2 It is a cross-sectional view of the tube expanding of the utility model.

[0014] In all the drawings, the reference numerals are specifically as follows: 1, tube expander; 2, conical cavity; 3, reserved hole; 4, barb; 5, flank; 6, bolt. Specific embodiments

[0015] As Figure 1-2 shown: A new type of internal expansion screw includes a tube expander 1. The inner wall of the upper half of the tube expander 1 is provided with a thread groove. The lower half of the tube expander 1 is provided with a conical cavity 2. The outer wall of the lower half of the tube expander 1 is provided with a plurality of reserved holes 3. The inner bottom wall of the reserved hole 3 is fixedly connected with a barb 4. The outer wall bottom of the tube expander 1 is fixedly connected with several flanks 5.

[0016] The barb 4 is in the shape of a petal. The number of barbs 4 is three or four. The reserved hole 3 is located at the bottom end of the internal expansion screw. The tip of the barb 4 faces the top. The bottom end of the barb 4 is connected to the tube expander 1.

[0017] The conical cavity 2 starts from the cut-off point of the thread groove on the inner wall of the tube expander 1 and extends to the top end of the reserved hole 3.

[0018] The flank 5 is in the shape of a triangular pyramid and is located at the bottommost end of the outer wall of the tube expander 1.

[0019] The bolt 6 is in threaded fit with the tube expander 1.

[0020] During use, only need to insert the internal expansion screw of the utility model into the pre-drilled hole, and then the bolt 6 can be screwed into the rear end. After the bolt 6 is screwed in, the head of the bolt 6 will expand the conical cavity 2 that becomes narrower towards the front. Further, the petal-shaped barbs 4 will expand simultaneously, thereby locking the drilled hole. The flank 5 prevents the internal expansion screw from rotating in the drilled hole before the barbs 4 expand. The internal expansion screw of the utility model is faster and simpler in construction.

Claims

1. A new type of internal expansion screw, characterized in that, It includes an expansion tube (1). Thread grooves are provided on the inner wall of the upper half of the expansion tube (1), a conical cavity (2) is provided in the lower half of the expansion tube (1), a plurality of reserved holes (3) are provided on the outer wall of the lower half of the expansion tube (1), barbs (4) are fixedly connected to the inner bottom wall of the reserved holes (3), and a number of side wings (5) are fixedly connected to the bottom of the outer wall of the expansion tube (1).

2. The novel internal expansion screw according to claim 1, characterized in that, The barbs (4) are in the shape of petals, and the number of barbs (4) is three or four. The reserved holes (3) are located at the bottom end of the inner expansion screw. The tips of the barbs (4) face the top, and the bottom ends of the barbs (4) are connected to the expansion tube (1).

3. A novel internal expansion screw according to claim 1, characterized in that, The conical cavity (2) starts from the cut-off point of the thread groove on the inner wall of the expansion tube (1) and extends to the top of the reserved hole (3).

4. A novel internal expansion screw according to claim 1, characterized in that, The side wings (5) are in the shape of a triangular pyramid and are located at the bottommost end of the outer wall of the expansion tube (1).

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