Power tool having object detection

Patent metadata

Field	Value
Publication number	US-11085582-B2
Application number	US-201816115087-A
Country	US
Kind code	B2
Filing date	Aug 28, 2018
Priority date	Aug 30, 2017
Publication date	Aug 10, 2021
Grant date	Aug 10, 2021

Abstract

A power tool and methods are provided for detecting objects (e.g., flesh or other materials) in the operating path of a power tool's output component (e.g., saw blade or drill bit). An object detection sensor in the power tool generates an output signal indicative of a type of material detected in the operating path of the power tool. A power tool controller receives the object detection sensor output and determines when a material in the operating path of the power tool changes. The controller changes operation of a motor of the power tool (e.g., increasing or decreasing speed or stopping the motor) in response to the detected material change. The object detection sensor may include, for example, an RF sensor, a capacitive sensor, a camera, a conductivity probe, or an ultrasound probe.

First claim

What is claimed is:

1. A method of operating a power tool including a motor and an output component, the method comprising:
receiving user input that identifies a material of a target workpiece;
driving, by the motor, an output component of the power tool, the power tool having an operating path based on a direction of motion of the output component;
receiving, at a controller of the power tool, output signals from an object detection sensor of the power tool and a trigger switch of the power tool;
determining, by the controller, whether flesh is present in the operating path of the power tool;
inhibiting operation of the motor until the material of the target workpiece is detected and the absence of flesh is confirmed based on the signals of the object detection sensor;
activating the motor according to the signals received from the trigger switch when the material of the target workpiece is detected and the absence of flesh is confirmed; and
interrupting power to the motor in response to determining that the flesh is present in the operating path of the power tool.

2. The method of claim 1 wherein the object detection sensor includes at least one selected from a group of a radio frequency (RF) sensor, a capacitive sensor, a camera, a conductivity probe, and an ultrasound probe.

3. The method of claim 1 , wherein the controller is configured to detect the presence of the flesh in the operating path of the power tool based on detection of conductivity of air in the operating path of the power tool.

4. The method of claim 1 further comprising:
receiving, by the controller, user input for selecting a sensitivity level of the object detection sensor; and
adjusting, by the controller, the sensitivity of the object detection sensor, wherein the determining of whether the flesh is in the operating path of the power tool includes determining whether the flesh is in the operating path of the power tool based on the adjusted sensitivity.

5. A method of operating a power tool including a motor and an output component, the method including:
receiving user input that identifies a material of a target workpiece;
driving, by the motor, an output component of the power tool, the power tool having an operating path based on a direction of motion of the output component;
receiving, at a controller, output signals from an object detection sensor of the power tool and a trigger switch of the power tool;
determining, by the controller based on the output signal from the object detection sensor, that an object is present in the operating path of the power tool and that the object is of a certain type;
inhibiting operation of the motor until the material of the target workpiece is detected and an absence of other types of materials is confirmed based on the signals of the object detection sensor;
activating the motor according to the signals received from the trigger switch when the material of the target workpiece is detected and the absence of the other types of materials is confirmed; and
interrupting power to the motor in response to determining that the object that is present in the operating path of the power tool is of the certain type.

6. The method of claim 5 , wherein the controller is configured to detect the presence of the object in the operating path of the power tool based on detection of conductivity of air in the operating path of the power tool.

7. The method of claim 5 , wherein the interruption of the power to the motor is based on a type of the material indicated by the output signal of the object detection sensor of the power tool.

8. The method of claim 5 further comprising:
receiving, by the controller, user input for selecting which certain type of object detected by the object detection sensor causes the interruption of the power to the motor.

9. The method of claim 5 , further comprising:
receiving user input that selects a sensitivity level of the object detection sensor; and
adjusting the sensitivity of the object detection sensor, wherein the determining that the object is present in the operating path of the power tool includes determining that the object is present in the operating path of the power tool based on the adjusted sensitivity.

10. A method of operating a power tool including a motor and an output component, the method including:
driving, by the motor, an output component of the power tool, the power tool having an operating path based on a direction of motion of the output component;
receiving, at a controller, a first output signal from an object detection sensor of the power tool and a second output signal from a switch of the power tool, the object detection sensor configured to detect an object in the operating path; and
determining, by the controller, whether an object is present in the operating path of the power tool;
inhibiting operation of the motor until a material of a target workpiece is detected and absence of the object is confirmed based on the first output signal from the object detection sensor;
activating, by the controller, power to the motor according to the second output signal received from the switch when the material of the target workpiece is detected, and the absence of the object is confirmed; and
interrupting power to the motor in response to determining that the object is present in the operating path of the power tool.

11. The method of claim 10 , wherein the first output signal from the object detection sensor indicates that a first object is present in the operating path of the power tool and that the first object is of a certain type.

12. The method of claim 10 , wherein the first output signal from the object detection sensor indicates that an object of a certain type was not detected by the object detection sensor.

Assignees

• Milwaukee Electric Tool Corp

Inventors

• Mergener Matthew J

Classifications

• B23Q17/2438

  of an operator or a part thereof · CPC title

• F16P3/141

  using sound propagation, e.g. sonar · CPC title

• F16P3/147

  using electro-magnetic technology, e.g. tags or radar · CPC title

• B25F5/00

  Details or components of portable power-driven tools not particularly related to the operations performed and not otherwise provided for · CPC title

• B23Q11/0082

  by determining whether the operator is in a dangerous position (B23Q17/2438 takes precedence) · CPC title