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. 01, 1989
Filed:
Mar. 07, 1988
Friedrich Schwing, Gelsenkirchen, DE;
Friedrich Wilh. Schwing GmbH, Hern, DE;
Abstract
In a spool valve for thick matter pumps comprising at least one slide rod running forward and backward which is movable in a guide means and surrounded by a seal, and a drive consisting of working pistons associated with each slide rod, the working pistons each cooperating with one end of the slide rod directed out of a valve casing, and their driving cylinders ending a distance away from the valve casing, the end of the slide rod which runs forward out of the casing being cleaned of adhering thick matter during the backward movement of the piston, the invention provides for the guide means to be disposed on the inside and the seal separate therefrom to be disposed on the outside in front thereof on the valve casing, and for the parts supported loosely on each other in the operative connection between the working piston and the end of the slide rod to provide a gap which is used for assembling and dismounting the seal, the cleaning of the end of the slide rod being effected by the stripping action of the seal.