Electricity: conductors and insulators – Conduits – cables or conductors – Single duct conduits
Reexamination Certificate
2000-09-22
2001-11-27
Reichard, Dean A. (Department: 2831)
Electricity: conductors and insulators
Conduits, cables or conductors
Single duct conduits
C174S069000, C174S1020SP
Reexamination Certificate
active
06323425
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a method of producing a one-piece corrugated jacket pipe of thermoplastic comprising the steps of forming a thermoplastic tube; shaping the tube into a corrugated pipe, which is closed over its circumference and has an axis and a corrugated section formed by a first corrugated partial section and a second corrugated section, the partial sections being such that when radially overlapping each other, the first partial section lies radially outwards and engages with the radially inward second partial section; cutting the corrugated pipe parallel to the axis in a cutting plane for the corrugated partial sections to form; thermally deforming the corrugated pipe such that the two corrugated partial sections lie one above the other radially and lap over each other in a peripheral direction. The invention further relates to a method of inserting at least one electric line into such a corrugated jacket pipe.
2. Background Art
A method of the generic type is known from WO98/32 202. In this case, the corrugated jacket pipe is thermally formed in such a way that the first corrugated partial section rests radially outwards on, and engages with, the second corrugated partial section directly after the forming. Practice has shown that the engagement of the first and the second corrugated partial section does not take place with the required radial prestress. This may result in small gaps forming so that electric lines might get squeezed or damaged. Moreover, the corrugated jacket pipe may open when bent during installation for instance in a vehicle, and the electric lines disposed in it may come out. This too may lead to damages of the electric lines.
This also applies to the corrugated jacket pipe known from WO97/32 379.
SUMMARY OF THE INVENTION
It is an object of the invention to develop the method of the generic type so that the corrugated partial sections engage with each other by sufficiently high radial prestress after the installation of the electric lines.
In a method according to the invention, this object is attained by the first partial section and the second partial section being deformed thermally such that the first partial section lies radially inwards—related to the second partial section—and that the two partial sections lap over each other in the peripheral direction. The measures according to the invention help ensure that the first corrugated partial section, which lies radially outwards after the installation of at least one electric line and once the corrugated jacket pipe has been closed, is positioned radially inwards in the corrugated pipe prior to the installation of the electric line, this corrugated pipe constituting an intermediate product, so that after the change of the radial position of the two partial sections relative to each other, these sections bear against each other by high radial prestress in the position in which they overlap each other.
The method of how to open the corrugated pipe produced according to the invention and how to close it after the insertion of at least one electric line is characterized in that in the vicinity of the cutting plane, an aperture is formed between the corrugated partial sections by spreading them elastically in the peripheral direction; in that at least one electric line is inserted through the aperture into the corrugated pipe; and in that by closing the aperture, the first corrugated partial section is moved to lap radially outwards over the second corrugated partial section in the peripheral direction by elastic restoring forces of the corrugated pipe.
Further advantages and features of the invention will become apparent from the ensuing description of an exemplary embodiment of the invention, taken in conjunction with the drawing.
REFERENCES:
patent: 3892912 (1975-07-01), Hauck
patent: 4970351 (1990-11-01), Kirlin
patent: 6034329 (2000-03-01), Kawamura
patent: 6051789 (2000-04-01), Kato
patent: 6164338 (2000-12-01), Holzer et al.
patent: 3405552A1 (1985-08-01), None
patent: 3640226A1 (1988-06-01), None
patent: 4410706A1 (1995-10-01), None
patent: 19705761A1 (1998-08-01), None
patent: 0268869B1 (1994-03-01), None
Groebmair Maximilian
Hegler Ralph Peter
Conte Robert F. I.
Lee Mann Smith McWilliams Sweeney & Ohlson
Reichard Dean A.
Walkenhorst W. David
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