Claims
- 1. A safety device for the drive of a closing member, comprising a switch for the drive and a mechanical overload sensor made in the form of a nut located on a shaft of the drive, said nut being spring-loaded at both end faces thereof; displacement of said sensor along the shaft causing said sensor to interact with the switch arranged to cut said drive out should an overload thereof arise, characterized in that said nut comprising a flywheel having an inertial mass sufficient for providing axial displacement thereof under variations in speed of said shaft, said nut being coupled to said shaft by means of a non-braking thread.
- 2. A safety device as claimed in claim 1, said closing member including a reduction gear; a high-speed rotatable gear shaft operatively engaged with said reduction gear, said shaft having a threaded portion of the quick-pitch thread type, said flywheel being mounted on said threaded shaft portion; and return spring means imparting an axial force to said flywheel so as to cause said flywheel to run reversely toward an initial position in the absence of an overload acting on said drive.
Parent Case Info
The present application is a continuation application of Ser. No. 298,632; filed Oct. 18, 1972.
US Referenced Citations (5)
Continuations (1)
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Number |
Date |
Country |
Parent |
298632 |
Oct 1972 |
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