Expanded – threaded – driven – headed – tool-deformed – or locked-thr – Headed fastener element with nut – washer – securing means or cap – Deformable securing means
Patent
1993-05-20
1996-06-18
Saether, Flemming
Expanded, threaded, driven, headed, tool-deformed, or locked-thr
Headed fastener element with nut, washer, securing means or cap
Deformable securing means
411276, F16B 1905
Patent
active
055271405
DESCRIPTION:
BRIEF SUMMARY
FIELD OF THE INVENTION
The invention refers to a bush (riveting collar) to be formed around a closing part, with indentations, of a lockbolt rivet by means of a tool which applies a axial force, thus producing a high-strength riveted joint; the bush has substantially the shape of a hollow cylinder. The invention also shows a tool for carrying out the forming of a bush on a closing part, with indentations, of a lockbolt rivet under application of an axial force, whereby said tool has a pincer section for gripping the break-off part of the lockbolt rivet and a set-head which acts in conjunction with the bush.
A lockbolt riveted joint normally consists of a lockbolt rivet and a bush. The lockbolt rivet has a shank supporting a head at one end, and the other end of which changes to a closing part as well as a break-off part. A break-off groove is provided between closing Dart and breakoff part. The bush acts in conjunction with the closing part of the lockbolt rivet during the forming of said bush. It is shaped like a hollow cylinder and during the forming process it is changed, through deformation and work-hardening, into such a shape that the material from which it is made flows, at least partly, into the indentations in the closing part of the lockbolt rivet.
A bush of the aforementioned type is known from DE-PS 32 15 228, DE-OS 30 25 676 or U.S. Pat. No. 3,915,053. The bush is in each case shaped like a hollow cylinder, the axial length of which matches the closing part of the associated lockbolt rivet. The front parts of the bush may be rounded off or be provided with a chamfer which serves to ease the handling. Upon forming the bush on the closing part of the lockbolt rivet, it is known to employ a tool which has a pincer section and a set-head. The pincer section grips the break-off part of the lockbolt rivet and via the set-head the bush is subjected to plastic deformation. During its deformation, the bush is acted upon by an axial force, in fact a compressive force which gives rise to axial tensions in the bush which in turn lead to the deformation. High deformation forces and axial tensions are necessary in order to let the bush flow in the desired manner. It is particularly important here that the material of the bush fills the indentations in the closing part of the lockbolt rivet as much as possible or even completely. This happens depending on the particular shape and arrangement of the indentations in the closing part of the lockbolt rivet shank.
The axial tensions required for deforming the bush and the associated axial deformation forces are very large. The larger the forces, the easier and more complete is the deformation of the bush. However, the deformation forces, as axial forces at the head of the lockbolt rivet, are supported by the component concerned. As the head of the lockbolt rivet is in many cases relatively small, the force which can be transmitted is limited. If this force is exceeded, the head breaks off. High deformation forces and axial tensions are necessary for getting the material of the bush to flow. If lower axial forces and correspondingly lower tensions are employed, the indentations in the closing part of the lockbolt rivet will not be completely filled by the bush. The consequence of this is that the strength of the riveted joint is also correspondingly lower.
SUMMARY OF THE INVENTION
It is the object of the invention to demonstrate a bush of the aforementioned type and/or to create a tool, the use of which results in an easier flowing of the material of the bush into the indentations in the closing part of the lockbolt rivet.
According to the invention, this is achieved with the bush of the aforementioned type in that it has a shape which deviates from rotational symmetry, that a torsional stress is superimposed on the axial tension during the forming of the bush on the closing part of the lockbolt rivet, whereby the material of the bush flows into the indentations in the closing part under the simultaneous action of the axial tension and the torsional stress. Th
REFERENCES:
patent: 550898 (1895-12-01), Richardson
patent: 2330511 (1943-09-01), Money
patent: 2542376 (1951-02-01), Torresen
patent: 3139786 (1964-07-01), Ardell
patent: 3464472 (1969-09-01), Reynolds
patent: 3560124 (1971-02-01), Bergere
patent: 4254809 (1981-03-01), Schuster
patent: 4544312 (1985-10-01), Stencel
patent: 4759237 (1988-07-01), Fauchet
patent: 4768910 (1988-09-01), Rath
"Machine Design", Apr. 9, 1981, B. F. Goodrich, p. 126.
Mages Walter
Turlach Gerhard
Huck International GmbH & Co.
Saether Flemming
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