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. 19, 1977
Filed:
Aug. 02, 1971
John A Richards, Tustin, CA (US);
Other;
Abstract
A concrete hopper has a plurality of arcuate channels in its bottom portion, preferably lined with a resilient material, such as rubber. The hopper includes a discharge end with discharge outlets formed therein in communication with the channels. A sliding sleeve-piston combination is associated with each channel for segregating and discharging a portion of the concrete through its associated discharge outlet. In other words, the sleeves are alternately filled by moving them through the hopper, and the pistons are operated to force the concrete out of the sleeves. A slide valve assembly including a discharge nozzle for connecting to a discharge hose and a pair of wear plates controls the discharge of pumped concrete from the discharge outlets. Hydraulic control means are included which automatically program the sequential operation of the sliding sleeve-piston combinations and the sliding valve. The pumping apparatus is designed to prevent the crushing of rock during shifting of the slide valve by being constructed so that the ends of the pistons and sleeves when fully extended lie in the same plane as the wear faces of the valve wear plates.