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US 12,303,989 B2Granted
Actuators for power tool safety systems
AssigneeSawStop Holding LLC
InventorStephen F. Gass
Life of this patent
Estimating the term…
Abstract
Fast-acting and low-inertia actuators useable in various applications where a high force must be applied very quickly are disclosed. Power tools with detection systems configured to detect a dangerous condition between a person and a cutting tool are disclosed. In power tools, for example in a woodworking machine, a fast-acting and low-inertial actuator as disclosed herein can be used to retract a blade upon detection of a dangerous condition by a detection system. The actuator includes a charge of pressurized fluid and one or more electromagnets to selectively retain or release the pressurized fluid.
Claims7
A power tool comprising:
- a blade for cutting workpieces;
- a motor configured to drive the blade;
- a structure supporting the blade and configured to allow the blade to retract;
- an electromagnet to trigger a retraction of the blade;
- and
- a circuit to control the first electromagnet,
- where the electromagnet has a first metal part, a second metal part, a gap between the first metal part and the second metal part, and a coil of wire around the first metal part and within the gap between the first metal part and the second metal part;
- where the coil of wire is connected to the circuit;
- where the first metal part has a first surface, and the second metal part has a second surface;
- and further comprising a third metal part contacting at least one of the first surface and the second surface;
- where the third metal part moves out of contact with at least one of the first surface and the second surface to retract the blade;
- and
- where the electromagnet controls whether the third metal part moves out of contact with at least one of the first surface and the second surface.
10 more elements
Dependencies are inferred from the claim text.