Bus bar unit and brushless motor

A bus bar unit comprising:

• a conductive bus bar including a plate-shaped base plate portion;
• and
• a resin holder configured to cover the base plate portion, wherein
• the holder includes:
• an exposure portion that exposes only a part of the base plate portion in a first direction of a thickness direction of the base plate portion;
• and
• a guide portion that is attached to the exposure portion and guides a conductive wire to be joined to the part from a second direction opposite to the first direction to the first direction,
• the part is provided at a position excluding both end portions of the base plate portion in an extension direction thereof, and
• portions, which are adjacent to both sides of the part in the extension direction, of the base plate portion are covered with the holder without being exposed.

A bus bar unit applied to an inner rotor brushless motor including a ring-shaped stator and a rotor located on a radially inner side of the stator, the bus bar unit comprising:

• a conductive bus bar including a plate-shaped base plate portion;
• and
• a resin holder configured to cover the base plate portion, wherein
• the holder includes:
• an exposure portion that exposes only a part of the base plate portion in a first direction of a thickness direction of the base plate portion;
• and
• a guide portion that is attached to the exposure portion and guides a conductive wire to be joined to the part from a second direction opposite to the first direction to the first direction,
• the conductive wire is a start wire of a winding forming a coil of the stator, and is drawn out in a predetermined axial direction of an axial direction of the stator,
• in a state where the first direction is aligned with the predetermined axial direction,
• the holder is mounted on the predetermined axial direction side of the stator,
• the guide portion is a through-hole that penetrates in the axial direction and through which the start wire is inserted, and
• the exposure portion is a notch that exposes the part of the base plate portion in the predetermined axial direction on the inner side or a radially outer side of the through-hole, and
• the notch is provided on the inner side of the through-hole.

A brushless motor of an inner rotor type, the brushless motor comprising:

• a bus bar unit;
• a ring-shaped stator on which the bus bar unit is mounted;
• and
• a rotor located on a radially inner side of the stator and configured to rotate integrally with a shaft on the inner side of the stator, wherein
• the bus bar unit includes:
• a conductive bus bar including a plate-shaped base plate portion;
• and
• a resin holder configured to cover the base plate portion,
• the holder includes:
• an exposure portion that exposes only a part of the base plate portion in a first direction of a thickness direction of the base plate portion;
• and
• a guide portion that is attached to the exposure portion and guides a conductive wire to be joined to the part from a second direction opposite to the first direction to the first direction,
• the conductive wire is a start wire of a winding forming a coil of the stator, and is drawn out in a predetermined axial direction of an axial direction of the stator,
• in a state where the first direction is aligned with the predetermined axial direction,
• the holder is mounted on the predetermined axial direction side of the stator,
• the guide portion is a through-hole that penetrates in the axial direction and through which the start wire is inserted, and
• the exposure portion is a notch that exposes the part of the base plate portion in the predetermined axial direction on the inner side or a radially outer side of the through-hole,
• the stator is provided with coils of three phases,
• the bus bar is a terminal that connects coils of two different phases among the coils of the three phases and is electrically connected to an external power feeding device, and comprises a plurality of the bus bars,
• the holder includes the through-holes and the notches as many as the bus bars, and
• the start wires of the windings forming the coils of the two different phases connected by each of the bus bars are drawn out from the same slot in the predetermined axial direction, inserted through the common through-hole, and joined to the part of the bus bar.