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:
Sep. 01, 1992
Filed:
Apr. 17, 1991
Johannes Bottger, Weinbohla, DE;
Falk Buschmann, Coswig, DE;
KBA-Planeta AG, Radebeul, DE;
Abstract
The pneumatic controller for detecting the presence or absence of sheets fed through a press machine includes a suction system having a suction duct in a sheet feed cylinder of the press machine and a vacuum pump connected to the suction duct, the suction duct opening onto a surface of the sheet feed cylinder on which one of the sheets contacts at least partially obstructing an air flow through the suction duct during normal press operation. To rapidly detect a sudden increase in the air flow through the suction duct caused by a missing sheet, the pneumatic controller is provided with a flow sensor (1) in the suction duct having a hot wire (16) and a surrounding protective jacket (15), and an analyzing circuit (2) connected to the flow sensor. The analyzing circuit (2) detects the temporary cooling of the hot wire (16) caused by the increase in the air flow rate and the analyzing circuit (2) detects the change of resistance of the wire and generates and amplified voltage output signal.