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:
Dec. 05, 1989
Filed:
May. 02, 1988
Knut C Schoeps, Tyreso, SE;
Atlas Copco Aktiebolag, Nacka, SE;
Abstract
A hydraulic torque impulse generator comprises a drive member (10) connected to a rotation motor and including a cylindrical fluid chamber (12) partly defined by a circumferential wall (14), and an output spindle (13) rotatably supported in coaxial relationship with the drive member (10) and having a rear portion (15) extending into the fluid chamber (12). The rear spindle portion (15) has two radial slots (18, 19) each supporting a radially movable seal element (21, 22) for sealing cooperation with seal lands (23, 24) on the fluid chamber wall (14). First seal ridges (25, 26) are provided on the rear spindle portion (15) for sealing cooperation with second seal ridges (28, 29) on the fluid chamber wall (14), thereby dividing the fluid chamber (12) into two high pressure compartments (H.P.) and two low pressure compartments (L.P.) during two short intervals of each revolution of the drive member (10) relative to the output spindle (13). A valve spindle (39) which is non-rotatively connected to the drive member (10) and rotatively supported in a coaxial bore (35) in the rear spindle portion (15) is provided with both a cam (40) for engaging the seal elements (21, 22) for urging the seal elements (21, 22) into contact with the fluid chamber wall (14), and passages (42, 43) formed therein for cooperation with passages (44, 45) in the rear spindle portion (15) for short circuiting the fluid chamber compartments (H.P. and L.P.) during every second one of the intervals.