Power tool
AssigneeMakita Corporation
InventorsTatsuya Nagahama, Junya Inuzuka, Takashi Momose
Life of this patent
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Abstract
A power tool (1; 90) includes a motor (17) having a stator (18) and a rotor (19). The stator (18) includes front and rear insulators (21, 22) respectively disposed forward and rearward of a stator core (20) in an axial direction thereof. At least six coils (23) are respectively wound on the stator (18) such that the coils (23) are wound through the front and rear insulators (21, 22). Winding wires (23a) respectively electrically connect circumferentially-adjacent pairs of the coils (23). A short circuiting device (25) short circuits respective pairs of windings (23a) that are located diagonally or diametrically across from one another.
Claims19
A power tool comprising:
- a motor having a stator and a rotor, the stator including front and rear insulators respectively disposed forward and rearward of a stator core in an axial direction thereof,
- at least six coils respectively wound on the stator such that the coils are wound on the front and rear insulators,
- winding wire segments respectively electrically connecting circumferentially-adjacent pairs of the coils,
- a short circuiting element comprising electrically conductive elements that respectively connect pairs of the winding wire segments that are positioned diagonally across from one another, and
- a sensor circuit board provided between the short circuiting element and one of the front or rear insulator, the sensor circuit board having at least one rotation detection device for detecting positions of permanent magnets provided on the rotor or on a centrifugal fan.
A power tool comprising:
- a motor having a stator and a rotor, the stator including front and rear insulators respectively disposed forward and rearward of a stator core in an axial direction thereof,
- at least six coils respectively wound on the stator such that the coils are wound on the front and rear insulators,
- winding wire segments respectively electrically connecting circumferentially-adjacent pairs of the coils,
- a short circuiting means that short circuits respective pairs of the winding wire segments that are positioned diagonally across from one another, the short circuiting means comprising a number of electrically conductive elements corresponding to the number of pairs of the winding wire segments that are positioned diagonally across from one another, each of the electrically conductive elements having a pair of short circuiting pieces,
- wherein radially outer portions of the short circuiting pieces each have a slit defined therein.
Dependencies are inferred from the claim text.