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:
May. 31, 1994
Filed:
Mar. 19, 1993
Friedrich Schwing, Gelsenkirchen, DE;
Friedrich Wilh. Schwing GmbH, , DE;
Abstract
A slurry pump for mixing concrete includes a charge funnel, a pair of discharge cylinders, and a discharge line operable with each other to form a slurry flow control. A control valve has an exit port connected with the discharge line and an entrance port that is alternatively positioned in front of an opening of each discharge cylinder. A pair of gate valve disks are positioned one on each side of the entrance port. The size of each gate valve disk conforms to a surface between the discharge cylinder openings such that in a change-over midpoint of the control valve the openings of the discharge cylinders are sealed off by the gate valve disks, and the entrance port and the control valve is sealed off on the surface between the discharge cylinders for the execution of a partial stroke a discharge cylinder piston which compresses the drawn in slurry. A compensation cylinder prevents slurry interruptions during the change-over the control valve. A combinatorial circuit controls the drive of each discharge cylinder and the slurry flows such that during the change over of the control valve the compensation cylinder pushes slurry into the discharge line and such that during a subsequent discharge cycle of one of the discharge cylinders the compensation cylinder is filled with slurry. A combinatorial circuit lets the drive of the discharge cylinder actually delivering slurry deliver faster in proportion to the amount of the slurry taken in by the compensation cylinder. The combinatorial circuit delays the change over of the control valve such that one of the gate valve disks closes off the opening of the discharge cylinder associated with it.