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:
Jul. 02, 2002
Filed:
Oct. 12, 2000
Howa Machinery, Ltd., Aichi-Ken, JP;
Abstract
A rotary cylinder actuator has a piston rod placed in a cylinder, provided in its surface with a guide groove and capable of being moved axially between a position corresponding to a clamping angular position and a position corresponding to an unclamping angular position. A guide member is attached to the cylinder to engage in the guide groove. The piston rod turns from a first angular end position toward a second angular end position for normal turning and turns from the second angular end position toward the first angular end position for reverse turning. The opposite guide surfaces of the guide groove serve as a first guide surface for normal turning and a second guide surface for reverse turning, respectively, so that the guide member moves relative to the piston along different paths in the guide groove while the piston rod turns for normal turning and reverse turning, respectively. The first guide surface and the second guide surface are formed so that the guide member moves relative to the piston rod along a path having a shape of a section of a sine curve or a cosine curve in a final stage of movement of the piston rod, and the guide member moves relative to the piston rod so as not to produce any torque at the second angular end position.