DC motor with dual commutator bar set and selectable series and parallel connected coils
First Claim
1. A power tool comprising:
- a motor;
the motor having an armature including;
a first set of armature coils wound on a lamination stack;
a second set of armature coils wound on said lamination stack; and
a switching system that connects the two sets of armature coils in either series or parallel configurations.
1 Assignment
0 Petitions
Accused Products
Abstract
A permanent magnet, DC motor especially well adapted for use in power tools, and particularly hand-held, battery powered power tools. The motor includes two sets of armature coils, with each set of coils being coupled to separate sets of commutator bars on an armature. Separate pairs of brushes are used to interface with the two sets of commutator bars. A switching subsystem is controlled either manually by a user engageable switch or automatically by a controller, to connect the two sets of coils in either series or parallel configurations. The series configuration provides a greater efficiency, but with a lower power output than the parallel connection. The parallel connection provides a greater maximum power output from the motor. Thus, the operating characteristics of the tool can be tailored to better meet the needs of a work task, and in a manner than makes most efficient use of available battery power.
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Citations
20 Claims
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1. A power tool comprising:
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a motor; the motor having an armature including; a first set of armature coils wound on a lamination stack; a second set of armature coils wound on said lamination stack; and a switching system that connects the two sets of armature coils in either series or parallel configurations. - View Dependent Claims (2, 3, 4, 14, 15)
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5. A power tool comprising:
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an electric motor; the motor having an armature including; a first set of armature coils wound on a lamination stack; a second set of armature coils wound on said lamination stack; and a switching system that connects the two sets of armature coils in a first configuration to provide maximum power output, and a second configuration to provide a maximum motor efficiency. - View Dependent Claims (6, 7, 8, 9, 10, 11, 12, 13, 16)
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17. A power tool comprising:
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an electric motor; the motor having; an output shaft; an armature mounted on the output shaft, a lamination stack; a first set of armature coils wound on the lamination stack; a second set of armature coils wound on said lamination stack; and a plurality of switches for selectively electrically connecting the first and second sets of armature coils; a controller that controls the switches to connect the two sets of armature coils in a first configuration to provide maximum power output, and a second configuration to provide maximum motor efficiency. - View Dependent Claims (18, 19, 20)
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Specification