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. 26, 1988
Filed:
Jul. 01, 1987
Fernand Copie, Minneapolis, MN (US);
Other;
Abstract
A vibratory drum soil or asphalt compactor has a variable vibratory mechanism selectively operable to vary the vibrations imparted to the drum from a balanced mode to a maximum amplitude vibratory mode independently of the vibratory mechanism shaft rotation. A shaft having a shaft chamber for accommodating fluid is rotatably mounted on the drum. The shaft is equipped with a cylinder having a cylinder chamber connected with a passage to the shaft chamber. A piston closing the cylinder chamber and slidably mounted on the cylinder supports an eccentric weight. A control piston located with the shaft chamber operated by an external linear actuator is operable to move the piston away from the cylinder thereby move the weight into engagement with the shaft to balance the shaft and allow the weight to move away from the shaft to produce maximum vibration upon rotation of the shaft. The control piston is equipped with check valves operable to release excess fluid from the shaft chamber and add fluid to the shaft chamber to compensate for fluid volume variations due to thermal expansion and contraction.