JP4680405B2 - Self-piercing expansion anchor and self-piercing expansion anchor system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an expansion anchor, and more particularly to a self-drilling expansion anchor and a self-drilling expansion anchor system.
[0002]
[Prior art]
Known expansion anchors generally include a sleeve having an expansion tab. This expansion tab expands by, for example, displacing a dowel or shank in the axial direction in a prepared hole previously drilled in concrete or the like. The inflatable tab includes a plurality of cutters that form undercuts in the pilot hole as the sleeve rotates in the pilot hole, as disclosed, for example, in U.S. Pat. Nos. 5,816,760, 5,911,550, and 5,911,733. Have.
[0003]
As described in US Pat. No. 5,911,733 and German Patent No. 3,535,262, it is well known to embed a hard alloy insert in place on an expansion tab to form a self-drilling expansion anchor. Yes.
[0004]
[Problems to be solved by the invention]
The present invention aims to improve a self-drilling expansion anchor according to the prior art.
The present invention aims to provide a new self-drilling expansion anchor that is reliable and economical.
It is an object of the present invention to provide a novel self-drilling expansion anchor having an expansion portion with an integrally formed blade portion.
It is an object of the present invention to provide a novel self-drilling expansion anchor having at least a pair of blades provided for corresponding expansions disposed substantially opposite each other across the diameter of the anchoring shaft. Yes.
[0005]
[Means for Solving the Problems]
According to the present invention, in the self-drilling expansion anchor, the shaft has a conical portion, the sleeve member has a plurality of expansion portions disposed around the shaft, and at least some of the expansion portions of the sleeve member. The blade portion and the corresponding expansion portion are formed from an integral member, and at least two expansions arranged substantially opposite to each other across the diameter of the shaft have the blade portion. A self-drilling expansion anchor is provided in which at least one inflatable portion between the inflatable portions having the blade portion is not provided with a blade portion .
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1, the self-drilling expansion anchor includes a shaft 10 and an expansion sleeve member 20. The shaft 10 has a conical portion 12 which is provided coaxially and has a substantially conical shape. The expansion sleeve member 20 has an expansion portion 22 that is disposed around the expansion sleeve member.
[0009]
Referring to FIG. 3, the expansion portions 22 of the expansion sleeve member 20 are separated from each other by a slot 23 formed between the expansion portions of the sleeve member 20. In the present embodiment, the sleeve portion 20 of the inflatable portion is formed with a deformed portion including a groove 21 in the vicinity of the upper portion of the inflatable portion, and the inflatable portion can be easily inflated.
[0010]
1 and 2, the inflatable portion 22 of the inflatable sleeve member 20 is provided coaxially with the central axis of the shaft 10 and has an end opposite to the conical portion 12 of the shaft. Yes. With this configuration, as will be described later, when the expanding portion 22 is displaced in the axial direction along the conical portion 12 of the shaft, the expanding portion 22 expands outward.
[0011]
In FIG. 1, the self-drilling expansion anchor is arranged in a pilot hole 2 formed in advance in, for example, brick, stone, concrete or other material. The expansion anchor also includes one or more blade portions 30 protruding from the expansion portion 22 of the expansion sleeve member 20. As will be described later, the blade portion 30 forms the undercut 4 in the prepared hole when the expansion sleeve member 20 rotates.
[0012]
In the self-drilling expansion anchor shown as an example, a drive sleeve member 40 formed with a screw is provided around the shaft above the expansion sleeve member 20 and is engaged with the screw portion 14 of the shaft. Thereby, the expansion sleeve member 20 is displaced in the axial direction by rotating the drive sleeve member 40 about the shaft on which the thread portion is formed.
[0013]
The drive sleeve member 40 has an engagement end that complementarily engages and rotates the engagement end of the expansion sleeve member 20. As an example, in the embodiment shown in FIG. 3, the drive sleeve member has one or more teeth 42 that are engageable in corresponding recesses 24 of the expansion sleeve member.
[0014]
In other embodiments, the inflatable sleeve member, and more particularly the inflatable portion and blade portion, can be rotated within the pilot hole by other means.
By rotating the drive sleeve member 40 about the shaft 10 having a threaded portion, the expansion sleeve member 20 rotates, and the expansion sleeve member 20 advances along the conical portion 12 of the shaft. Thereby, the expansion part 22 expand | swells. In FIG. 2, the undercut 4 is formed by the blade portion 20 when the expanding portion 22 rotates and advances in the lower hole 2.
[0015]
In one embodiment, the expanding portion 22 and its blade portion 30 may be formed as a single piece. Preferably, the blade part 30 hardens the corresponding part of the expansion part 22 by heat treatment, for example, nitriding treatment.
In an embodiment shown as an example, the expansion sleeve member, the expansion portion and the blade portion thereof are formed of a single alloy steel having a carbon content of 0.40 to 0.50 (mass%) and a relatively high aluminum content. It consists of members.
[0016]
In one embodiment, the alloy steel is an Al—Cr—Mo alloy, for example, an alloy steel known as SACM645. An example of an Al—Cr—Mo alloy steel suitable for this application is about 0.40 to 0.50 (mass%) carbon C, about 0.15 to 0.50 (mass%) silicon Si, about 0 Manganese Mn not exceeding .60 (mass%), Phosphorus P not exceeding about 0.03 (mass%), Sulfur S not exceeding 0.03 (mass%), Chrome of about 1.30 to 1.70 It contains Cr, about 0.15 to 0.30 (mass%) molybdenum Mo, and about 0.70 to 1.20 (mass%) aluminum Al. Other suitable alloys may be used.
[0017]
In one embodiment suitable for anchoring applications to certain types of concrete, the inflatable portion 22, particularly its upper portion that deforms upon expansion, has a Vickers hardness of about 250 and the blade portion 30 has a Vickers hardness. The hardness is about 1000 or more.
[0018]
These approximate hardness values are given by way of example only, and vary significantly depending on the construction of the expansion sleeve member and the specific anchoring application, such as the requirements from concrete aggregate.
[0019]
In the embodiment shown in FIG. 3, the blade portion 30 protrudes in a generally radial direction from the end portion 26 of the corresponding inflating portion 22 that is opposed to the conical portion of the shaft. 3 and 4, it protrudes from the peripheral surface of the expansion sleeve member.
[0020]
In other embodiments, only some of the inflatable portions have a blade portion, and preferably the blade portion of the inflatable portion adjacent to the inflatable portion having the blade portion is omitted. For example, in FIG. 3, the expansion part 25 adjacent to the expansion part 22 having the corresponding blade part 30 does not have a blade part. The blade part 30 of the expansion part 22 can also be formed so as to extend in the axial direction beyond the end part 27 of the expansion part 25.
[0021]
Preferably, at least a pair of blade portions are provided in the inflatable portion disposed on the substantially opposite side across the diameter of the inflatable sleeve member. In the embodiment shown in FIG. 4, the blade portions 30 are provided on exactly two inflatable portions 22 arranged on the opposite sides of the inflatable sleeve member 20 across the diameter. With this configuration, when the expansion sleeve member 20 is attached to the shaft, the two blade portions are accurately disposed on substantially opposite sides across the diameter of the shaft.
[0022]
The inflatable sleeve member preferably also has at least one inflatable portion that does not have an inflatable portion between the inflatable portions having the blade portions. For example, in FIG. 4, a plurality of inflatable portions 22 that do not include a blade portion are disposed between the inflatable portions that include the blade portion 30.
[0023]
The expansion sleeve member 20 of FIG. 4 is also preferably formed integrally, and the blade portion thereof is hardened more than the portion that deforms at least during expansion of the expansion portion as described above, for example, by heat treatment.
[0024]
From the description of the present invention, those skilled in the art can make and use embodiments of the present invention that are presently considered optimal, but can contemplate other variations, combinations or equivalents of particular embodiments of the present invention. . The invention is therefore not limited to the embodiments described above, but extends to all embodiments within the scope of the claims.
[Brief description of the drawings]
FIG. 1 is a partial cross-sectional view of one embodiment of a self-piercing expansion anchor prior to placement in a pilot hole.
FIG. 2 is a partial cross-sectional view of a self-drilling expansion anchor disposed within a pilot hole.
FIG. 3 is a side view of an embodiment of an inflation sleeve and drive sleeve member having an inflation portion with an integrally formed blade portion.
FIG. 4 is an end view of an inflating part.
[Explanation of symbols]
2 ... lower hole 4 ... undercut 10 ... shaft 12 ... conical part 14 ... threaded part 20 ... expansion sleeve member 21 ... groove 22 ... expansion part 23 ... slot 24 ... recess 30 ... blade part 40 ... drive sleeve member 42 ... tooth Part

Claims (6)

In self-piercing expansion anchors,
A shaft having a conical portion;
A sleeve member having a plurality of inflatable portions disposed around the shaft;
A blade portion protruding from at least some of the inflating portions of the sleeve member,
The blade portion and the corresponding expansion portion are formed from an integral member, and at least two expansions disposed substantially opposite to each other across the diameter of the shaft have the blade portion, and the expansion having the blade portion Self-drilling expansion anchor in which at least one expansion section between the sections is not provided with a blade section .   The self-drilling expansion anchor according to claim 1, wherein the blade portion is a portion obtained by heat-treating a corresponding expansion portion.   The self-drilling expansion anchor according to claim 1, wherein the sleeve member, the expansion portion and the blade portion are integrally formed from an alloy steel containing carbon and aluminum having a relatively high content.   The expansion portion of the sleeve member is disposed substantially concentrically with respect to the shaft, and has an end opposite to the conical portion, and the blade portion has a radius from the end of the corresponding expansion portion. The self-piercing expansion anchor according to claim 1 projecting in a direction.   The self-drilling expansion anchor according to claim 4, wherein the blade portion protrudes from a peripheral surface of a corresponding expansion portion. The self-piercing expansion anchor according to claim 1, wherein the expansion portion has a hardness of about 250 Vickers hardness , and the blade portion has a hardness of at least about Vickers hardness of about 1000.

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