Chainsaw safety feature
AssigneeMilwaukee Electric Tool Corporation
InventorsBrian A. Cornell, Craig A. Kottke, Andrew W. Beilfuss
Life of this patent
Estimating the term…
Abstract
A chainsaw including a guide bar; a chain disposed around the guide bar and movable relative to the guide bar; a motor operably coupled to the chain to drive the chain about the guide bar; a handle; a speed controller in communication with the motor to affect a motor speed; and a momentary switch, wherein the momentary switch restricts actuation of the speed controller when the momentary switch is in a resting state, wherein the momentary switch allows actuation of the speed controller when the momentary switch is in an activated state, wherein the momentary switch comprises a base rotatably coupled to the handle and an articulated arm rotatably coupled to the base, and wherein the momentary switch is biased to the resting state.
Claims20
A chainsaw comprising:
- a guide bar;
- a chain disposed around the guide bar and movable relative to the guide bar;
- a motor operably coupled to the chain to drive the chain about the guide bar;
- a handle;
- a speed controller in communication with the motor to affect a motor speed, wherein the speed controller comprises a locking surface;
- and
- a momentary switch, wherein a complementary locking surface of the momentary switch interacts with the locking surface of the speed controller to restrict actuation of the speed controller when the momentary switch is in a resting state, wherein the momentary switch allows actuation of the speed controller when the momentary switch is in an activated state, wherein the momentary switch comprises a base rotatably coupled to the handle and an articulated arm rotatably coupled to the base, and wherein the momentary switch is biased to the resting state.
A momentary switch for a chainsaw, the momentary switch comprising:
- a base configured to be rotationally coupled to a handle of the chainsaw;
- an articulated arm rotatably coupled to the base;
- a first biasing element configured to bias the base to a first rotational position with respect to the handle;
- and
- a second biasing element configured to bias the articulated arm to a second rotational position with respect to the base,
- wherein the articulated arm defines a driving surface, wherein the base defines a driven surface, wherein the driving surface is configured to bias the driven surface when force is applied to the articulated arm, wherein the driving surface is disengaged from the driven surface when the momentary switch is in a resting state, and wherein the driving surface is interfaced with the driven surface when the momentary switch is in an intermediate state and an activated state.
A method of using a chainsaw, the method comprising:
- applying a force to an articulated arm of a momentary switch of a chainsaw to cause the momentary switch to reconfigure from a resting state to an intermediate state by rotating the articulated arm relative to a base of the momentary switch, wherein applying the force to cause the momentary switch to reconfigure from the resting state to the intermediate state causes a driving surface of the articulated arm to contact a driven surface of the base;
- continuing to apply force to the momentary switch to reconfigure the momentary switch from the intermediate state to an activated state;
- actuating a speed controller of the chainsaw after the momentary switch is reconfigured to the activated state;
- and
- maintaining force on the momentary switch to maintain the momentary switch in the activated state, wherein the momentary switch is biased toward the resting state.
Dependencies are inferred from the claim text.