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:
Aug. 10, 1982
Filed:
Jun. 23, 1980
Oy Tampella AB, , FI;
Abstract
A hydraulic percussion apparatus comprising a body, a cylinder in the body and a percussion piston reciprocating in the cylinder. A distributing valve moves in a valve housing. A valve for starting and stopping the percussion apparatus is provided. A hydraulic pump and hydraulic channels form a percussion circuit with a gas/liquid pressure accumulator. A distributing valve circuit and a free circulation circuit are provided for the pump which are parallelly coupled with the percussion circuit, which circuits are connected to the pump and to the start-and-stop valve which has positions for controlling pressure in the circuits. The start-and-stop valve has a middle position during which pressure in the percussion circuit rises up to a predetermined value while the distributing valve circuit remains closed independent of the pressure in the percussion circuit.