PURPOSE: To obtain a tube which can be contracted in the radial direction only, by expanding a plastic tube to have an inner diameter greater than an object inner diameter, fitting the resulting tube around a grease-coated cylinder having an outer diameter equal to the object inner diameter of the tube, and thermally contracting the tube.
CONSTITUTION: An electron beam is applied to a plastic tube, which is obtained by extrusion molding or drawing, to thermally expand the same. The expanded plastic tube 7 is fitted around a rotating metal cylinder 4 having a layer of coating 6 of a grease-like material. The cylinder is rotated at a high speed as it is heated by a heater 8. Since the plastic tube 7 is rotated as it is floated to a small extent due to the grease 6 with respect to the cylinder 4, a tube-contracting force further generated during the heating operation is applied in the direction of the length of the tube. As a result, the tube 7 is contracted in the direction of the length thereof. This tube 7, which is never contracted in the direction of the length thereof, is used as a cable connector tube.
KURANASHI HIROAKI
NEGISHI YASUO
TOKUMARU YUUZOU
SUMITOMO ELECTRIC INDUSTRIES
| JPS4826267A | 1973-04-06 | |||
| JP43017833A |
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