Motor driven hand-held device containing a displacement mass

• US 4,638,870 A
• Filed: 12/11/1984
• Issued: 01/27/1987
• Est. Priority Date: 12/21/1983
• Status: Expired due to Fees

• Current Assignee: Hilti Aktiengesellschaft (Hilti Martin Family Trust)
• Original Assignee: Hilti Aktiengesellschaft (Hilti Martin Family Trust)
• Inventors: Kousek, Heinz
• Primary Examiner(s): Schran, Donald R.
• Assistant Examiner(s): Wolfe, James L.
• Application Number:
  US06/680,390
• Time in Patent Office: 777 Days
• Field of Search: 173/12, 173/20, 81/479, 338/32 H, 200/220, 200/190, 310/11, 192/142 R, 192/150, 408/5, 408/6
• US Class Current: 173/183
• CPC Class Codes: B25F 5/00 Details or components of portable power-driven tools not particularly related to the operations performed and not otherwise provided for
• CPC Class Codes: Y10T 408/14 Responsive to condition of Tool or tool-drive

Abstract

A motor driven hand-held device for rotating a tool, includes a housing with an axis of rotation containing an electrically conductive liquid mass located within a sealed non-electrically conductive container. A magnetic field is established in the housing by a permanent magnet and a part of the liquid mass is located within the magnetic field. If the housing is turned or twisted around the axis of rotation, relative movement takes place between the liquid mass and the container in the magnetic field. Due to the movement of the mass in the magnetic field, a voltage is induced in the mass and the voltage can be tapped by electrodes extending into the container. The tapped voltage can be used as an electrical signal.

Claims

1. Motor driven hand-held device for imparting rotary movement to a tool inserted into said device, comprising a housing having a rotational axis, a mass located within said housing, a sealed container located within said housing and formed of a non-electrically conductive material, said container comprises a hollow cylinder with the cylindrical axis diposed in parallel relation with the rotational axis of said housing, said cylinder is rigidly secured to said housing, said mass located within said container and comprising an electrically conductive liquid, said container arranged in said housing so that said mass is movable relative to said container in a direction extending perpendicularly of the rotational axis, means within said housing for forming a magnetic field with said electrically conductive liquid at least partially traversing said magnetic field, and means for tapping voltage induced in said electrically conductive liquid by the relative movement of said electrically conductive liquid with respect to the magnetic field.

2. Motor driven hand-held device as set forth in claim 1 wherein said means for forming a magnetic field comprises a permanent magnet for generating the magnetic field with said permanent magnet located adjacent said container.

3. Motor driven hand-held device, as set forth in claim 2, wherein said container has a pair of opposite ends spaced apart in the direction of the cylindrical axis thereof said permanent magnet rigidly secured in said housing and located adjacent the circumferential periphery of said container, a yoke connected to each of two opposite sides of said permanent magnet which sides are spaced apart in the direction of the rotational axis of said housing, and said yokes projecting from said permanent magnet inwardly toward the cylindrical axis of said container adjacent to the opposite ends of said container.

4. Motor driven hand-held device, as set forth in claim 1, wherein said means for tapping voltage comprises a pair of electrodes mounted in said container and extending into said electrically conductive liquid therein.

5. Motor driven hand-held device, as set forth in claim 4, wherein a connecting wire is attached to each of said electrodes and an amplifier connected to each of said wires for amplifying the voltage taken off from said electrically conductive liquid by said electrodes.

6. Motor driven hand-held device, as set forth in claim 1, wherein said means for tapping voltage includes an induction element.

7. Motor driven hand-held device, as set forth in claim 1, wherein said electrically conductive liquid is mercury.