CN107304780A - Expansion fastening device - Google Patents

Abstract

The present invention provides an expansion fastening device, comprising a first screw, including a screw head and a screw connected to the lower part of the screw head and having an external thread, the first screw having an internal thread hole extending axially downward from the top end, and a plurality of slots are provided at the rear end of the screw, so that a plurality of expansion parts are formed at the rear end of the screw; and a second screw, including a screw head and a screw core connected to the lower part of the screw head and having an external thread; wherein the screw core of the second screw can be inserted and locked in the internal thread hole through the top end of the first screw, and penetrate downward to a position where the expansion part is pushed outward to expand.

Description

expansion fastening device

technical field

The invention relates to a fastening device, especially a fastening device that can be widely used on walls and various boards. It is composed of two sub-screws. After pre-drilling a preparatory hole on the wall, it can be used directly without knocking. An expansion fastening device that can be installed by turning the electric screwdriver.

Background technique

The currently known expansion screw mainly includes a sleeve, a screw that can penetrate the sleeve, and a nut that is screwed on the screw. The end edge of the screw is formed with an enlarged end. After a preparatory hole is drilled in the wall in advance, the screw rod is moved outward by turning the nut, and the bottom end of the casing is propped up by the enlarged end of the screw rod against the preparatory hole, so that An expansion screw can be fixed in this prepared hole.

However, the above-mentioned expansion screw needs to be drilled with tools such as an electric drill bit in advance to dig out a preparatory hole at the locking position before use, and the diameter of the preparatory hole must match the outer diameter and length of the expansion screw, and should not be too large or too small , so it is quite troublesome and time-consuming to implement.

In addition, because the drill bit will continue to wear and shrink and become thinner due to the drilling operation, in actual operation, the drill bit needs to be replaced continuously to avoid the expansion screw being unable to be inserted into the hole due to the small diameter of the prepared hole Or get stuck in the prepared hole.

Finally, when inserting the expansion screw, it needs to be tapped with a mallet or a hard object to allow the expansion screw to completely enter the prepared hole, but often the angle is limited, making it difficult to tap, resulting in unstable or incomplete construction quality.

Contents of the invention

Therefore, the main purpose of the present invention is to provide a kind of expansion fastening device that can be widely used on walls and various boards. .

In order to achieve the above purpose, the present invention proposes an expansion fastening device composed of two sub-female screws, and as long as the pre-drilled holes are drilled on the wall surface, no need to knock, just use an electric screwdriver to insert it directly The expansion fastening device for installation, and the construction work is quick and easy, and the structure is more streamlined.

The expansion fastening device of the present invention is mainly composed of two screws, including:

A first screw includes a screw head and a screw connected under the screw head to form an outer thread, the first screw has an inner screw hole extending axially downward from the top end, and a screw hole is provided at the tail end of the screw has a plurality of slots so that the end of the screw is formed with a plurality of spreaders; and

A second screw, including a screw head and a screw core connected under the screw head to form external thread teeth;

Wherein, the screw core of the second screw can be inserted and locked into the inner screw hole through the top end of the first screw, and goes deep down to the position where the expansion part is pushed outward.

In the present invention, the inner screw hole formed on the first screw communicates with the slot.

In the present invention, the inner screw hole of the first screw includes an inner thread section and a section without inner thread.

In the present invention, the screw core of the second screw includes a striker.

In the present invention, the end of the lance is bullet-shaped.

In the present invention, after the second screw is locked and combined with the first screw, the screw head of the second screw is stacked against the screw head of the first screw.

It can be seen from the above description that the expansion fastening device provided by the present invention is composed of two sub-screws. After pre-drilling the pre-drilled hole on the wall, it is no longer necessary to tap and directly use an electric screwdriver to insert it. Innovative structure for installation.

Description of drawings

Fig. 1 is a three-dimensional exploded view of the expansion fastening device of the present invention;

Figure 2 is an exploded plan view of the expansion fastening device of the present invention;

Fig. 3 is a three-dimensional combined schematic view of the expansion fastening device of the present invention;

Fig. 4 is a schematic diagram of the use of the expansion fastening device of the present invention;

Fig. 5 is a second schematic diagram of the use of the expansion fastening device of the present invention;

Fig. 6 is a schematic diagram of the third use of the expansion fastening device of the present invention;

Fig. 7 is a fourth schematic diagram of the use of the expansion fastening device of the present invention.

Explanation of reference signs: expansion fastening device 100; first screw 10; screw head 11; screw 12; external thread 121; expansion part 122; internal screw hole 13; internal thread segment 131; ; Split groove 14; Second screw 20; Screw head 21; Screw core 22; Outer thread 221; Lever 222;

detailed description

Please refer to FIGS. 1 and 2 to disclose the expansion fastening device of the present invention. As shown in the figures, the expansion fastening device 100 mainly includes a first screw 10 and a second screw 20 .

The first screw 10 includes a screw head 11 and a screw 12 connected under the screw head 11 to form an external thread 121. The first screw 10 has an inner screw hole 13 extending axially downward from the top end. , and the tail end of the screw 12 is provided with a plurality of split grooves 14, so that the tail end of the screw 12 is formed with a plurality of expansion parts 122. Wherein, the inner screw hole 13 formed on the first screw 10 communicates with the sectional groove 14, and the inner screw hole 13 of the first screw 10 includes an inner thread segment 131 and an inner screw thread segment 131 without inner thread. Thread segment 132 .

The second screw 20 includes a screw head 21 and a screw core 22 connected under the screw head 21 and formed with external thread 221 . Wherein, the screw core 22 of the second screw 20 includes a lance 222, and the end of the lance 222 is bullet-shaped.

In this way, as shown in FIG. 3 , the screw core 22 of the second screw 20 can be inserted and locked into the inner screw hole 13 through the top end of the first screw 10 , and go deep down to push the expansion part 122 toward the The position of the outer brace.

For actual implementation and use, please refer to FIG. 4 , FIG. 5 , FIG. 6 and FIG. 7 , which are schematic diagrams showing the use of the expansion fastening device 100 of the present invention when it is installed on the wall 30 .

The installation steps of the expansion fastening device 100 of the present invention only need a few actions to complete, as shown in Fig. 4, first, use an electric screwdriver to align the first screw 10 with the pre-drilled pre-drilled hole and then insert it. Locked into the wall 30.

After completing the wall positioning of the first screw 10, continue as shown in Figure 5 and Figure 6, as long as the second screw 20 is inserted into the inner screw hole 13 from the top of the first screw 10, and then the screw of the second screw 20 is passed The screw portion 221 of the core 22 is screwed with the inner screw segment 131 of the inner screw hole 13 of the first screw 10 , so that the second screw 20 and the first screw 10 can be screwed together.

As shown in Figure 7, after the above actions are completed, use an electric screwdriver to continue to rotate the second screw 20 downwards until the striker 222 is pushed against the bottom of the inner screw hole 13, and then continue to push the top down to make the The expansion portion 122 at the tail end of the screw 12 is stretched outward, and is tightly and firmly embedded in the wall 30 through the external thread 121 formed on the expansion portion 122 .

After the locking combination of the second screw 20 and the first screw 10 is completed, the screw head 21 of the second screw 20 is stacked against the screw head 11 of the first screw 10 .

If the expansion fastening device 100 needs to be removed from the wall 30, the first screw 10 and the second screw 20 can be quickly withdrawn from the wall 30 by reverse operation for repeated use.

It can be seen from the above description that the expansion fastening device 100 provided by the present invention is composed of two sub-female screws. After pre-drilling the preparatory hole on the wall surface, it is no longer necessary to tap and directly use an electric screwdriver to insert it. Innovative structure for installation.

Through the above detailed description, it can be fully shown that the purpose and efficacy of the present invention are progressive in implementation, and it is unprecedented in the market, and fully meets the requirements of the patent, so the application is filed according to law; however, the above, It is only a preferred embodiment of the present invention, and should not be used to limit the implementation scope of the present invention. For example, all equivalent changes and modifications made according to the protection scope of the present invention shall fall within the protection scope of the present invention.

Claims (6)

1. a kind of expansion fastening device, it is characterised in that include：

One first screw, includes a screw head and is connected to a screw of screw head external screw teeth formed below, First screw has the inner bolt hole extended down from top axial, and is cutd open in the screw tail end provided with plural number Groove, makes the screw tail end be formed with plural expanded support portion；And

One second screw, includes a screw head and is connected to a screw of screw head external screw teeth formed below Core；

Wherein, the screw core of second screw can be locked in the interior spiral shell via the top insertion of first screw Hole, and the position outwards supported down into the ejection expanded support portion.

2. expansion fastening device as claimed in claim 1, it is characterised in that：It is formed on first screw The inner bolt hole is connected with the profile groove.

3. expansion fastening device as claimed in claim 1, it is characterised in that：The inner bolt hole bag of first screw Containing internal screw thread section and one without internal screw thread section.

4. expansion fastening device as claimed in claim 2 or claim 3, it is characterised in that：The screw of second screw Core includes a lance.

5. expansion fastening device as claimed in claim 4, it is characterised in that：The end of the lance is in bullet-shaped.

6. expansion fastening device as claimed in claim 1, it is characterised in that：Second screw and first spiral shell Follow closely after combination lock, the screw head of second screw is folded against in the screw head of first screw.