Method of and apparatus for preventing accidents during working with hand-held tools with a rotatable working tool
First Claim
1. A method of preventing accidents caused by blockage of a rotatable tool when working with a hand-held tool including the rotatable tool (8), a drive motor (7) for driving the rotatable tool (8), and means (5, 6) for interrupting transmission of a drive torque from the drive motor (7) to the rotatable tool (8) dependent on an operational condition of the hand-held tool, the method comprising the steps of determining the operational condition of the hand-held tool by measuring displacement of the hand-held tool in space in at least two points of the hand-held tool spatially spaced from each other and spaced from a tool axis;
- subtracting two obtained displacement measurement variables (a1, a2) from each other, and thereafter, calculating an actuation signal that actuates the interrupting means (5,
6).
1 Assignment
0 Petitions
Accused Products
Abstract
A method of and an apparatus for preventing accidents caused by blockage of a rotatable tool when working with a hand-held tool including the rotatable tool (8), a drive motor (7) for driving the rotatable tool (8), and means (5, 6) for interrupting transmission of a drive torque from the drive motor (7) to the rotatable tool (8) dependent on an operational condition of the hand-held tool, with the method including determining the operational condition of the hand-held tool by measuring displacement of the hand-held tool in space in at least two points of the hand-held tool spatially spaced from each other and spaced from a tool axis; subtracting two obtained displacement measurement variable (a1, a2) from each other; and thereafter, calculating an actuation signal that actuates the interrupting means (5, 6); and with the apparatus including sensors and an evaluation circuit for implementing the method.
92 Citations
8 Claims
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1. A method of preventing accidents caused by blockage of a rotatable tool when working with a hand-held tool including the rotatable tool (8), a drive motor (7) for driving the rotatable tool (8), and means (5, 6) for interrupting transmission of a drive torque from the drive motor (7) to the rotatable tool (8) dependent on an operational condition of the hand-held tool, the method comprising the steps of determining the operational condition of the hand-held tool by measuring displacement of the hand-held tool in space in at least two points of the hand-held tool spatially spaced from each other and spaced from a tool axis;
- subtracting two obtained displacement measurement variables (a1, a2) from each other, and thereafter, calculating an actuation signal that actuates the interrupting means (5,
6). - View Dependent Claims (2, 3, 4)
- subtracting two obtained displacement measurement variables (a1, a2) from each other, and thereafter, calculating an actuation signal that actuates the interrupting means (5,
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5. An apparatus for preventing accidents caused by blockage of a rotatable tool when working with a hand-held tool including the rotatable tool (8), a drive motor (7) for driving the rotatable tool (8), and means (5, 6) for interrupting transmission of a drive torque from the drive motor (7) to the rotatable tool (8) dependent on an operational condition of the hand-held tool, the apparatus comprising at least two sensors located in a hand-tool housing and which are spatially spaced from each other and from a tool axis for measuring displacement of the hand-held tool in space in two points at which the sensors are located;
- and an electronic evaluation device (3) for processing displacement measurement variables (a1, a2) generated by the least two sensors and including a subtraction stage for subtracting the generated displacement measurement variables (a1, a2) from each other before calculating an actuation signal for actuating the interrupting means.
- View Dependent Claims (6, 7, 8)
Specification