Power tool printed circuit board including embedded busbars

Patent metadata

Field	Value
Publication number	US-12573919-B2
Application number	US-202418623721-A
Country	US
Kind code	B2
Filing date	Apr 1, 2024
Priority date	Apr 21, 2020
Publication date	Mar 10, 2026
Grant date	Mar 10, 2026

Abstract

A power tool that includes a motor and a printed circuit board (“PCB”). The motor includes a rotor and a stator. The stator includes a plurality of stator terminals. The PCB is electrically connected to the stator. The PCB includes a switch and an embedded busbar. A first end of the embedded busbar is electrically connected to the switch. The embedded busbar extends away from the PCB. A second end of the embedded busbar electrically connects to a stator terminal of the plurality of stator terminals for providing power to the motor using the switch. The embedded bus bar is embedded between two layers of the printed circuit board.

First claim

What is claimed is:

1 . A power tool comprising:
a motor including a rotor and a stator, the stator including a plurality of stator terminals; and a printed circuit board (“PCB”), the PCB including a switch and an embedded busbar, the embedded busbar electrically connecting the switch to a stator terminal of the plurality of stator terminals for providing power to the motor using the switch, wherein a portion of the embedded busbar is embedded between two layers of the printed circuit board.

2 . The power tool of claim 1 , wherein the switch is a plurality of switches and the embedded busbar is a plurality of embedded busbars.

3 . The power tool of claim 2 , wherein the plurality of switches includes six switches and the plurality of embedded busbars includes three embedded busbars.

4 . The power tool of claim 1 , wherein the stator terminal further includes:
a block portion; a metallic portion welded to the block portion; and an insulating portion, wherein the block portion and the metallic portion are recessed into the insulating portion, and wherein the plurality of stator terminals further comprises a radial aperture oriented radially with respect to the motor and orthogonally to a rotor axis of the motor.

5 . The power tool of claim 1 , wherein:
the PCB further includes a dielectric layer separating a power portion of the PCB from a sensing portion of the PCB; and the power portion includes the switch and the sensing portion includes a Hall-effect sensor.

6 . The power tool of claim 1 , wherein:
the stator terminal is mounted to a non-conductive block and includes a hook at a first end of the stator terminal and a post at a second end of the stator terminal; the post makes electrical contact with the embedded busbar; and the post includes a split tip.

7 . The power tool of claim 1 , wherein:
the stator terminal is further mounted to a conductive block; the conductive block includes an axial aperture oriented axially with respect to a rotor axis of the motor; and the axial aperture receives a fastener to fix the embedded busbar to the stator terminal.

8 . The power tool of claim 1 , wherein:
the stator terminal is mounted to a non-conductive block and includes a hook at a first end of the stator terminal and an axial aperture at a second end of the stator terminal oriented axially with respect to a rotor axis of the motor; and the axial aperture receives a fastener to fix the embedded busbar to the stator terminal.

9 . The power tool of claim 1 , wherein:
the stator terminal is mounted to a non-conductive block and includes a hook at a first end of the stator terminal; an axial screw thread extends through a second end into the non-conductive block, the axial screw thread oriented axially with respect to a rotor axis of the motor.

10 . A power tool comprising:
a motor including a rotor and a stator, the stator including a plurality of stator terminals; and a printed circuit board (“PCB”), the PCB including a switch and an embedded busbar, embedded busbar electrically connecting the switch to a stator terminal of the plurality of stator terminals for providing power to the motor using the switch, wherein the stator terminal is mounted to a block mounted to a stator core of the stator.

11 . The power tool of claim 10 , wherein:
the stator terminal includes a hook at a first end of the stator terminal; the stator terminal includes a post at a second end of the stator terminal; and the post makes electrical contact with the embedded busbar.

12 . The power tool of claim 10 , wherein:
the stator terminal includes an aperture at a second end of the stator terminal; and the aperture interfaces with at least a portion of the embedded busbar to make electrical contact with the embedded busbar.

13 . The power tool of claim 10 , wherein:
the block is conductive; the block includes an axial aperture oriented axially with respect to a rotor axis of the motor; and the axial aperture receives a fastener to fix the embedded busbar to the stator terminal.

14 . The power tool of claim 10 , wherein:
the stator terminal includes an axial aperture at a second end of the stator terminal oriented axially with respect to a rotor axis of the motor; and the axial aperture receives a fastener to fix the embedded busbar to the stator terminal.

15 . The power tool of claim 10 , wherein the block is non-conductive.

16 . A power tool comprising:
a motor including a rotor and a stator, the stator including a plurality of stator terminals; and a printed circuit board (“PCB”), the PCB including a switch and an embedded busbar, the embedded busbar electrically connecting the switch to a stator terminal of the plurality of stator terminals for providing power to the motor using the switch, wherein a portion of the embedded busbar extends beyond a periphery of the PCB to connect to the stator terminal.

17 . The power tool of claim 16 , wherein a first end of the embedded busbar is electrically connecting to the switch, wherein a second end of the embedded busbar is electrically connecting to the stator terminal of the plurality of stator terminals, and wherein the second end of the embedded busbar extends beyond the periphery of the PCB relative to a central axis of the PCB.

18 . The power tool of claim 16 , wherein power is provided to the motor from a power source by controlling the switch.

19 . The power tool of claim 18 , wherein the power source is a battery pack.

20 . The power tool of claim 16 , wherein:
the stator includes a stator insulator; and the stator terminal is recessed into the stator insulator.

Assignees

• Milwaukee Electric Tool Corp

Inventors

• Rutowski Lucas A
• Merget Maxwell L
• Fieldbinder Douglas R

Classifications

• H05K1/181

  associated with surface mounted components · CPC title

• H05K2201/10166

  Transistor · CPC title

• H05K2201/1009

  Electromotor · CPC title

• H05K2201/10272

  Busbars, i.e. thick metal bars mounted on the printed circuit board [PCB] as high-current conductors · CPC title

• H02K11/0094

  Structural association with other electrical or electronic devices · CPC title