The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 17, 1995
Filed:
Oct. 18, 1993
Nippon Oil Co., Ltd., Tokyo, JP;
Abstract
The present invention provides a CFRP-made optical cylinder comprising, as the main CFRP layers, (a) CFRP layers containing a carbon fiber arranged in a direction substantially parallel to the cylinder axial direction and (b) CFRP layers containing a carbon fiber arranged in a direction making an angle of substantially.+-.(40.about.50) degree to the cylinder axial direction, in which cylinder at least 50% by weight of the carbon fiber arranged in a direction substantially parallel to the cylinder axial direction has a linear expansion coefficient of -1.times.10.sup.-6 /.degree.C. or less and at least 50% by weight of the carbon fiber arranged in a direction making all angle of substantially.+-.(40.about.50) degree to the cylinder axial direction has a linear expansion coefficient of -1.times.10.sup.-6 /.degree.C. or less, and which cylinder has a linear expansion coefficient of -0.5.times.10.sup.-6 /.degree.C. to 0.5.times.10.sup.-6 /.degree.C. in the axial direction. In the present optical cylinder, the influence by the change in atmospheric temperature is very small. Further, in the production of the present optical cylinder, it has no distortion when subjected to heating and subsequent cooling to room temperature for molding, because it is well balanced in rigidity and strength.