SAFETY MECHANISM FOR SPECIAL MACHINES AND FIXTURES

• Main Author: WILLIAMSON R,US
• Format: Patent
• Language: English
• Published: 12.11.1974
• Subjects: BLASTING; ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVEFUNCTIONING OF MACHINES OR INSTALLATIONS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; HEATING; LIGHTING; MECHANICAL ENGINEERING; SAFETY DEVICES IN GENERAL; TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION; TECHNICAL SUBJECTS COVERED BY FORMER USPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; THERMAL INSULATION IN GENERAL; WEAPONS

A hand restraint safety mechanism for use by an operator of a production machine wherein (absent the present invention) the operator's hand are exposed to the hazard of being caught by moving elements of the machine when the machine is stroked. The hand restraints for the operator's hands are operatively coupled via cables with a fluidic power cylinder which is mounted in fixed dimensional relation to the machine with which the safety mechanism is used. The power cylinder is operative between restraining and released positions to control the length of each cable extended from a housing on which cylinder is mounted. When the cables are maximally extended, the operator can reach into the machine to load or unload a workpiece. When the cables are minimally extended, the operator's hands are positively removed from the areas of the machine where they might be caught by moving machine elements. The operation of the restraint cylinder is via a pneumatic control circuit which is operatively coupled with the machine with which the safety mechanism is in use. Only when the power cylinder is in the restraining position can a machine stroke, i.e. a machine cycle, be initiated. During the machine stroke the power cylinder cannot operate to the released position. The safety mechanism includes a failsafe valve means and circuit arrangement through which a fluidic machine start signal can be supplied to the machine only when the safety mechanism has positively removed both operator's hands from the danger area.