Power tool safety mechanisms
AssigneeBlack & Decker Inc.
InventorsMichael L. O'Banion, David A. Carrier
Life of this patent
Estimating the term…
Abstract
A sensing mechanism (12) for detecting user contact with an active portion (26) of the power tool (10) is provided. In addition, a safety mechanism (14) for preventing prolonged user contact with the active portion (26) of a power tool (10) is provided. The safety mechanism (14) is configured to actuate upon receipt of a signal from the sensing mechanism (12). According to a first aspect, the safety mechanism (14) is arranged to rapidly displace the active portion (26) away from a user extremity. Alternatively, according to a second aspect, the safety mechanism (14) is arranged to rapidly urge an extremity of the user away from the active portion (26) of the power tool (10).
Claims15
A power tool, comprising:
- a frame structure;
- a blade mounted on a spindle that is supported by the frame structure;
- a drive motor mounted to the frame structure and configured to drive the spindle;
- a strap disposed proximate to the blade and coupled at a first end to a frame structure;
- a biasing member engaged with the strap and operates to urge the strap into engagement with the blade;
- a deployment mechanism selectively coupled between the strap and the frame structure and, in response to an activation signal, operates to uncouple from the strap, the strap being disengaged from the blade when the deployment mechanism is coupled to the strap and the strap is biased by the biasing member into engagement with the blade when the deployment member is uncoupled from the pawl;
- a transmitter capacitively coupled to the blade and operable to transmit an electrical signal to the blade;
- a receiver capacitively coupled to the blade and operable to receive the electrical signal transmitted to the blade;
- a controller connected to the receiver and the deployment mechanism, the controller operable to detect a variation in the electrical signal and send an activation signal to the deployment mechanism when the variation in the electrical signal exceeds the threshold value, where the controller adjusts the threshold value based on an electrical load associated with the operation of the blade.
A power tool having an active portion, comprising:
- a support structure;
- a strap that selectively engages the active portion of the power tool;
- a strap carrier coupled to the support structure and coupled to a first end of the strap;
- and
- a deployment mechanism selectively coupled between a second end of the strap and the strap carrier and, in response to an activation signal, uncouples the strap from the strap carrier such that the strap engages the active portion of the power tool and thereby discontinues movement of the active portion of the power tool.
Dependencies are inferred from the claim text.