Expansion bolt

Patent metadata

Field	Value
Publication number	US-9810254-B2
Application number	US-201314412391-A
Country	US
Kind code	B2
Filing date	Jun 25, 2013
Priority date	Jul 2, 2012
Publication date	Nov 7, 2017
Grant date	Nov 7, 2017

Abstract

An expansion bolt including an anchor bolt having an expansion section, and further including an expansion sleeve which surrounds the anchor bolt and which can be expanded by retracting the expansion section, and a spring element arranged on the anchor bolt. The spring element can be tensioned by inserting the anchor bolt into a bore hole and can retract the expansion section of the anchor bolt into the expansion sleeve when it is released. An indicator element indicates when a rated tension of the spring element is reached.

First claim

What is claimed is:

1. A method for setting an expansion anchor including an anchor bolt having an expansion section; an expansion sleeve surrounding the anchor bolt and expandable by retracting the expansion section; a spring element situated on the anchor bolt and tensionable by inserting the anchor bolt into a bore hole, the spring element capable of retracing the expansion section of the anchor bolt into the expansion sleeve when tension is subsequently released; and an indicator element indicating when a setpoint tension of the spring element is reached, the method comprising:
providing the bore hole in a substrate;
driving the expansion sleeve of the expansion anchor into the bore hole by applying axial forces to the anchor bolt;
tensioning the spring element of the expansion anchor to the setpoint tension by applying axial forces to the anchor bolt, the indicator element indicating when the setpoint tension is reached; and
retracting the expansion section of the anchor bolt into the expansion sleeve by energy stored in the spring element, so that the expansion sleeve expands radially and anchors the expansion anchor in the bore hole.

2. The method as recited in claim 1 wherein the indicator element is mechanically connected to the anchor bolt.

3. The method as recited in claim 1 wherein the indicator element is situated on the spring element.

4. The method as recited in claim 1 wherein the spring element includes at least one disk spring, and the indicator element includes an indicator ring connected to the disk spring and detaching at least partly from the disk spring when the setpoint tension is reached.

5. The method as recited in claim 4 wherein the disk spring and the indicator ring surround the anchor bolt.

6. The method as recited in claim 1 wherein the indicator element is activatable by deformation of the spring element or by impact of an element linked to the anchor bolt.

7. The method as recited in claim 1 wherein the anchor bolt includes an axial support for the spring element formed by a nut situated on the anchor bolt.

8. The method as recited in claim 1 further comprising a stop on the anchor bolt, the stop limiting a displacement of the expansion sleeve beyond the expansion section.

9. The method as recited in claim 1 wherein the spring element has a degressive spring characteristic.

Assignees

• Hilti Ag

Inventors

• Eckstein Andreas
• Goldt Mathias
• Schaeffer Marc
• Dijkhuis Arjen Detmer
• Appl Joerg

Classifications

• F16B31/027 Primary

  with a bolt head causing the fastening or the unfastening tool to lose the grip when a specified torque is exceeded · CPC title

• F16B13/065 Primary

  fastened by extracting the screw, nail or the like · CPC title

• Y10T29/4994

  Radially expanding internal tube · CPC title

• F16B31/028

  with a load-indicating washer or washer assembly · CPC title

• F16B13/06 Primary

  combined with expanding sleeve {(F16B13/045 and F16B13/08 take precedence)} · CPC title