System and method for identification of contact between a human and a static implement in a power tool

摘要

A method of operating a power tool detects human contact with a non-moving implement in the power tool. The method includes generating a series of samples of an electrical signal passing through the non-moving implement, identifying a component for each sample in the series of samples of the electrical signal, identifying a first max−min value corresponding to a first plurality of samples in the series of samples occurring during a first periodic time interval with reference to a difference between a maximum value and a minimum value identified in the components of the first plurality of samples, and identifying human contact with the non-moving implement in response to the first max−min value being greater than a first predetermined threshold.

主权项

1. A method for detection of human contact with a non-moving implement in a power tool comprising:
generating, with a clock source in the power tool, a time varying electrical signal that passes through the non-moving implement; sampling, with a controller in the power tool, the time varying electrical signal passing through the non-moving implement to obtain a series of samples of the electrical signal; identifying, with the controller, a component for each sample in the series of samples; identifying, with the controller, a first max−min value corresponding to a first plurality of samples in the series of samples occurring during a first periodic time interval with reference to a difference between a maximum value and a minimum value identified in the components of the first plurality of samples; identifying, with the controller, human contact with the non-moving implement in response to the first max−min value being greater than a first predetermined threshold; and disabling, with the controller, an actuator in the power tool that is configured to move the non-moving implement in response to identifying the human contact with the non-moving implement.