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:
Jan. 26, 1988
Filed:
Oct. 23, 1985
Okumura Corporation, Osaka, JP;
Abstract
A rock crushing device which crushes a rock by an expandable member which is, after being inserted into a borehole formed in the rock, expanded by pressure of a liquid material injected thereinto, including a liquid pressure measuring device provided in a liquid supply hose and a processor connected to the liquid pressure measuring device for processing the liquid pressure converted into electric signals and the time interval during which the liquid pressure is measured, wherein a valve provided in the liquid supply hose is controlled to be closed when the value of the value corresponding to the decreased pressure of liquid material of the liquid pressure measured by the processor exceeds a predetermined value.