HK1002595B - Anchor expanded by impact - Google Patents

Description

The invention relates to a blower consisting of a partially slit metal case and a spreader body that can be inserted into the metal case, as described in claim 1.

The known impact machines of the above type (DE-U 76 12 316, DE-U 76 36 399) are generally made of a complete material, into which an inner wind is inserted, the core of which is tapered conically towards the front end. This core drill uses a screw-in which is inserted into the narrowing hole with a screw-in tool to stimulate the impact machine.The rejuvenating inner bore of this impeller is formed by indentations arranged so that in the inner surfaces of the longitudinal cutting-off spreader shells, spaced apart, transverse ridges are formed, increasing in height from rib to rib towards the input. However, at high spreading compressive forces, the indentations deform so that the spreading forces applied by the spreading body are not converted into the corresponding strengths of the impeller.

The purpose of the invention is to train a type of impactor in such a way that it can be manufactured inexpensively in a non-spoke working process but has the high extraction values of a full-material impactor.

The solution to this problem is achieved by the characteristics given in claim 1.

In order to make the punch-off, the contour of the winding of the metal shell is first cut out of a sheet metal strip in a punching and bending tool, the two sections forming the splitting joint being first suspended in an axial direction. In subsequent steps in the bending tool, the threaded holes are imprinted and the second section of the splitting joint is bent on the first section. To connect the two sections, for example, an imprint can be fixed from the outer surface of the second section, which is embedded in the outer surface of the first section. In further steps, the flat plate is then rolled into a double shell and connected with a screw.

In order to convert this split-size into a pulling force, the two adjacent sections must be connected by a sliding joint according to the invention. Without such a connection, the folded second section of the coupling shaft at the coupling point would be cut off from the first section at a lower tensile force, which would be achieved by means of a split-size of twice the wall thickness of the coupling point. The sliding joint between the two sections, for example by means of an embossing, welding or cross-screw joint, reduces the force on the coupling point.The metal casing is stamped from a sheet of plate and then rolled into a casing, the casings having a first section which is curved inwards, with a second section curved on the outside. This creates a narrowing into which a scattering body can be inserted to stimulate the impactor. A drawing on the casing and over the inner section of the casing produces a displacement of the axis between the two strands,The screw joint is not capable of transmitting high tensile forces, since there is no solid connection at the seam of the casing in the area of the thread.

The fastener, as defined in USA-1 372 035, is a screw-dwelling which is spread by inserting a screw into the inner-screw-in and narrowing part of the screw-dwelling. The narrowing of the thread is achieved by folding an outer section onto an inner section of the screw-dwelling, the thread shape being imprinted on both sections. When a force is applied to the screw, the thread is pulled out of the shell so that an axial displacement occurs between the screw-dwelling and the screw-dwelling. In this axial displacement, the threaded arches are flattened so that no force of excess is applied to the outer-screw-dwelling between the inner and the outer-screw-dwelling. In addition, when the screw-dwelling is extended, the load is applied to the back part of the screw-dwelling in such a way that the load is at least radially distributed.

The impact machinery of the invention can be used to achieve the same strength as the impact machinery made of a complete material, but the manufacturing costs are considerably lower as a result of the spannerless production in a punching and bending machine.

In order to maintain a uniform inner rejuvenation, it is appropriate to provide the inner surface of the second section on the first section with a phase corresponding to the angle of curvature of the first section.

Further appropriate arrangements are given in the subclauses and description.

The drawing shows examples of the invention.

It shows: Figure 1 the punch with the insertion of a spreader,Figure 2 the contour of the punch part,Figure 3 the connection of the two sections of the spreader shaft via a weld point andFigure 4 the connection of the two sections of the spreader shaft via a transverse rib joint.

The impact wrench 1 shown in Figure 1 consists of a metal casing 2 with a continuous bore, initially cylindrical and then tapering towards the front end in the area of the part intended for spreading.

The rejuvenation of borehole 3 following inner wind 4 is achieved by the inward curving of the blades 7 with the inner surfaces of the blades forming an angle α of approximately 5-7° to the centre axis of the impact shaft. On the outer surface of the first section 7a of the blades 7 a second section 7b is folded in such a way that the outer surface of the second section 7b, after folding, has approximately the same outer diameter as the blades in the inward wind zone. The folding creates a blast zone corresponding to the double point of deformation of the hull 2. A section 7a, at the 7b 8 high bending point, is connected to the outer surface of the second section 7b by a 9 wedge, which prevents bending.

The metal casing 2 is manufactured in a stamping and bending machine, in which the stamping contour 10 shown in Figure 2 is first extruded; subsequently, section 7b is rolled over onto the outer surface of section 7a to form the spreader shaft 7 at the bending point 8. Sections 7a and 7b are separated by a slot 11. At the same time, section 7a is given a slightly conical outline to allow section 7a to be bent at an angle a when the board is then rolled into the casing 2.

The inner thread 4 can be cut after rolling or by stamping the thread holes in the punching and bending tool.

Figure 3 shows a design in which the shear-resistant connection between section 7a and 7b is achieved by a welding point 15. In Figure 4 the shear-resistant connection is made by a gear formed by interlocking transverse ribs 16 on the outer surface of section 7a and the re-folded inner surface of section 7b. To achieve an even rejuvenation of borehole 3 in the area of the spray-shaft, the inner surface of the re-folded section 7b has a phase 17 corresponding to the angle of bend a.

Claims (6)

1. Impact-type anchor, consisting of a metal sleeve that has an internal thread (4) for the screwing in of a screw and is partially slit to form expansible legs, having a through bore (3) that is at first cylindrical and then in the region of the portion provided for expansion tapers towards the leading end, into which bore an expander body (5) can be driven to expand the impact-type anchor (1), the metal sleeve being stamped out of a sheet metal blank and then rolled up to form a sleeve and the expansible legs (7) having a first section (7a) that is bent inwards, onto the outer face of which first section there is bent round a second section (7b), characterized in that the two sections (7a, 7b) that rest one against the other and the sleeve (2) are connected to one another at their seam (14) so as to be shear-resistant.
2. Impact-type anchor according to claim 1, characterized in that the two sections (7a, 7b) of the expansible legs (7) are connected to one another by means of a punched point (9).
3. Impact-type anchor according to claim 1, characterized in that the two sections (7a,7b) of the expansible legs (7) are connected to one another by means of a spot weld (15).
4. Impact-type anchor according to claim 1, characterized in that the two sections (7a, 7b) of the expansible legs (7) are connected to one another by means of toothing that is formed by transverse ribs (16) that engage with one another.
5. Impact-type anchor according to claim 1, characterized in that the inner face of the section (7b) that rests against the outer face of the section (7a) is provided with a chamfer (17) that corresponds approximately to the angle (α) through which the first section (7a) bends inwards.
6. Impact-type anchor according to claim 1, characterized in that the angle (α) through which the first section (7a) bends inwards is of from 5 to 7°.