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. 30, 1996
Filed:
Apr. 21, 1995
Tomoyuki Okuyama, Ibaraki-ken, JP;
Takashi Takebayashi, Ibaraki-ken, JP;
SMC Kabushiki Kaisha, Tokyo, JP;
Abstract
A positioning detector detects whether a workpiece has been positioned on a reference surface even when the pressure of a fluid supplied from a fluid pressure source and applied to the workpiece varies. A fluid is jetted from a nozzle toward a surface of the workpiece, and a back pressure of the fluid developed behind the nozzle is detected. A fluid pressure bridge is composed of the nozzle, a variable restriction, and a pair of fixed restrictions, and is connected to a semiconductor pressure sensor for detecting the difference between the back pressure and the pressure of a fluid vented through the variable restriction. The semiconductor pressure sensor has output terminals connected to a plurality of comparators for comparing the pressure difference detected by the semiconductor pressure sensor with respective different thresholds. Depending on the detected pressure difference, the comparators produce a different combination of output signals to selectively energize a plurality of light-emitting diodes for allowing the user to visually confirm the positioning of the workpiece with respect to the reference surface.