JPH0143530Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Field of Use The present invention relates to a driving expansion anchor used for securing tools and equipment to surfaces such as concrete and stone.

Prior Art and its Problems A cast-in expansion anchor is composed of a main body whose tip expands in a hole drilled in concrete or the like, and a plug which expands the tip.

5, 6, and 7 show a conventional example of the bolt type, which has a thread 1 on the outer circumferential surface of the proximal end, a fitting hole 2 at the distal end, and a plurality of grooves 3 extending in the longitudinal direction. It is made up of a combination of a round bar-shaped main body 4 having a round bar shape and a conical plug 6 having a fitting end 5 having the same diameter as the fitting hole 2 at the distal end and gradually increasing in diameter toward the base end.

The one shown in Fig. 5 is the most common, but firstly, when drilling a hole in a wall or floor of concrete, if cuttings remain in the hole, the fitting end 5 cannot be fitted. When the plug 6 is inserted into the hole with the plug 6 fitted into the hole 2, cutting chips enter the outer circumferential surface of the plug 6 and enter the gap surrounded by the wall of the hole, the outer circumferential surface of the plug 6, and the tip surface of the main body 4. When the main body 4 is driven in, the accumulated cutting debris prevents the main body 4 from moving forward, making it impossible to fully expand the tip. Second, even if it can be expanded, the tip of the main body 4 is expanded by the plug 6 and moves forward while cutting the wall surface of the hole, resulting in new cutting debris, which accumulates in the gap. and prevent sufficient expansion.

Fig. 6 shows a plug 6 in which a flange 7 having a diameter approximately equal to the outer diameter of the main body 4 is provided at the proximal end in order to eliminate the above-mentioned drawback (Japanese Patent Publication No. 19129/1983), and Fig. (Utility Model Application Publication No. 19110/1983) in addition to a recess 8 on the proximal end surface, cutting debris remaining in the hole is removed from the flange 7.
This prevents it from being pushed into the bottom of the hole and going around into the gap, thus solving the first problem, but not solving the second problem.

When the tip of the main body 4 cuts the wall surface of the hole during driving and newly generated cutting debris prevents sufficient expansion, the flange 7 comes into contact with the wall surface of the hole and the plug 6 is fixed. When a pull-out force is applied to the main body 4 in the state of However, the main body 4 contracts and moves toward the entrance of the hole, and as a result, only the main body 4 is easily pulled out.

Means for Solving the Problems The present invention solves the above two problems and provides a driving expansion anchor that has a simple structure and stable pull-out resistance, and has a fitting hole at the tip and a longitudinal direction. A driving expansion anchor consisting of a combination of a main body having a plurality of grooves extending to the insertion hole, and a conical plug that is fitted into the fitting hole from the distal end and becomes larger in diameter toward the proximal end, the proximal end of the plug It is characterized by a structure in which the flange is freely removable.

Embodiment The present invention will be explained based on the embodiment shown in FIGS. 1 and 2. The proximal end has a screw 11 on the outer peripheral surface, a fitting hole 12 of an appropriate depth at the distal end, and a plurality of holes extending in the longitudinal direction, e.g. A main body 14 in the shape of a round bar with four grooves 13 equally spaced in the circumferential direction, and a conical shape having a fitting end 15 having the same diameter as the fitting hole 12 at the end and gradually increasing in diameter toward the base end. a plug 17 having a short cylindrical protrusion 16 at the center of the proximal end surface; and a disc-shaped flange 19 having a diameter larger than the proximal end surface and having a central attachment hole 18 fitted almost tightly into the protrusion 16. It consists of. This flange 19 is made to have approximately the same diameter as a hole drilled in concrete or the like.

FIG. 3 shows the driving expansion anchor of this embodiment being expanded in a hole 22 drilled in concrete 21. As shown in FIG. That is, the fitting end 1
When the main body 14 and the plug 17 are inserted into the hole 22 with the plug 5 fitted into the fitting hole 12, the cutting waste 23 remaining when the hole 22 is bored is pushed into the bottom of the hole 22 by the flange 19. Then, when the proximal end surface of the main body 14 is struck with a hammer or the like, the cutting waste 23 is compressed, and the main body 14 and the plug 17 move toward the bottom of the hole 22, while the tip of the main body 14 forms the conical shape of the plug 17. After the plug 17 is pushed in the most, the main body 14 is pushed further and the tip cuts and bites into the wall of the hole 22, resulting in the state shown in FIG. 3. It is. Cutting debris 23 generated as the tip moves forward while cutting the wall surface is deposited in the gap surrounded by the wall surface of the hole 22, the outer peripheral surface of the plug 17, the flange 19, and the main body 14.

When a pulling force is applied to the main body 14 and it moves to the entrance of the hole 22, the plug 17 pulls the flange 19 into the hole 22.
While remaining at the bottom of the main body 14, it is pulled out from the mounting hole 18 and moved together with the main body 14. For this reason, the tip of the main body 14 moves while being expanded by the plug 17 and does not contract, so it bites into the wall of the hole 22 again and generates a large pulling force (fourth point). (see figure).

It should be noted that the main body 14 may be of a nut type having a threaded hole that is continuous with the fitting hole 12 and opens at the proximal end surface, and the plug 17 may be pyramid-shaped. An annular or knurled unevenness may be provided on the outer circumferential surface of the distal end portion of the opening 14 to provide a structure that allows good engagement with the wall surface of the hole 22.

Effects of the invention According to the invention, the flange freely provided on the plug not only pushes remaining cutting waste into the bottom of the hole when it is inserted and driven into the hole and does not impede the forward movement of the main body, but also allows new Even if the generated cutting debris prevents sufficient expansion, the plug moves along with the main body due to the pulling force and does not shrink the expanded tip, so it bites into the wall of the hole again and generates a large pulling resistance. , equipment, and equipment can be fixed stably.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway side view of an embodiment of the present invention, Fig. 2 is an enlarged end view of the plug and flange, and Figs. 3 and 4 show the plug and flange in the expanded and fixed state. The partial vertical cross-sectional views, FIGS. 5, 6, and 7 are partially cut away side views of the conventional example. 12... Fitting hole, 13... Division groove, 14... Main body, 16... Protrusion, 17... Plug, 18... Mounting hole, 19... Flange.

Claims (1)

[Scope of utility model registration request] A driving expansion device consisting of a main body having a fitting hole at the distal end and a plurality of grooves extending in the longitudinal direction, and a conical plug that is fitted into the fitting hole from the distal end and becomes larger in diameter toward the proximal end. A driving expansion anchor characterized in that a flange is freely removably provided at the base end of the plug.