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:
Feb. 14, 1978
Filed:
Apr. 08, 1977
Nils G Virving, Vallingby, SW;
Defibrator Aktiebolag, Stockholm, SW;
Abstract
A system for measuring and regulating the grinding space between two metallic grinding discs and to prevent direct contact therebetween; one of the discs being rotated while the other one remains stationary to grind therebetween fibrous cellulosic material, such as moisture-containing wood chips, for pulp making. One of the discs is electrically insulated from the other parts of the system and is included in an electric circuit with the positive and negative terminals connected to the disc at points electrically insulated from one another and the moisture in the wood chips collected in the grinding space is used to produce a conductive cell, such as an electrolytic variable resistance, which bridges the two terminals and closes the circuit. The resistance of the cell which varies in response to fluctuations in the grinding space is measured by an ammeter or similar measuring device which thus gives a reading of the width of the grinding space. The measuring device may be used to actuate means for regulating the width of the grinding space and to stop the grinding operation immediately upon contact between the grinding discs.