Switch module for a power tool

Patent metadata

Field	Value
Publication number	US-2023041179-A1
Application number	US-202117392650-A
Country	US
Kind code	A1
Filing date	Aug 3, 2021
Priority date	Aug 3, 2021
Publication date	Feb 9, 2023
Grant date	—

Abstract

An electronic switch module includes a circuit board having conductive pads coupled to a power source and a sense pad coupled to an output signal; and a variable-speed actuator assembly having an actuator positioned adjacent a side edge of the circuit board and moveable along a movement axis, a plunger coupled to the actuator, and a conductive wiper secured to the plunger in contact with the circuit board. The wiper includes a first leg arranged to slidably engage the sense pad and a second leg arranged to slidably engage at least one of the conductive pads. The sense pad is longitudinally aligned with the conductive pads. The first leg of the wiper is located between the actuator and the second leg, and the sense pad is located between the side edge of the circuit board and the conductive pads.

First claim

1 . An electronic module comprising:
a circuit board comprising a plurality of conductive pads coupled to a power source and a sense pad coupled to an output signal; and a variable-speed actuator assembly including an actuator positioned adjacent a side edge of the circuit board and moveable along a movement axis perpendicular to the side edge, a plunger coupled to the actuator and moveable with the actuator along the movement axis, and a conductive wiper secured to the plunger in contact with the circuit board, the wiper having a first leg arranged to slidably engage the sense pad and a second leg arranged to slidably engage at least one of the plurality of conductive pads when the actuator is pressed; wherein the sense pad is longitudinally aligned with the plurality of conductive pads along an axis that is parallel to the movement axis of the actuator, and wherein the first leg of the wiper is located between the actuator and the second leg, and the sense pad is located between the side edge of the circuit board and the plurality of conductive pads.

2 . The electronic module of claim 1 , wherein the plurality of conductive pads is respectively coupled to a plurality of resistors arranged in series with the power source so the plurality of conducive pads outputs a varying voltage level that is coupled to the sense pad via the wiper based on a position of the actuator.

3 . The electronic module of claim 2 , wherein the plurality of conductive pads is printed on the circuit board as a metal layer including a plurality of gaps therebetween exposing the circuit board.

4 . The electronic module of claim 2 , further comprising an end pad disposed between the plurality of conductive pads and the sense pad, wherein the end pad outputs a voltage level different from the plurality of conductive pads.

5 . The electronic module of claim 4 , wherein the actuator is biased away from the circuit board to position the second leg of the wiper on the end pad in a default position of the actuator, and wherein movement of the second leg of the wiper from the end pad to the plurality of conducive pads produces a voltage variation indicative of an initial actuation of the actuator.

6 . The electronic module of claim 4 , wherein a distance between the end pad and the plurality of conductive pads is smaller than a distance between the end pad and the sense pad but greater than a distance between the respective ones of the plurality of conductive pads.

7 . The electronic module of claim 4 , wherein the plurality of conductive pads comprises a second end pad at a distal end thereof opposite the end pad, wherein the second wiper is arranged to engage the second end pad when the actuator is fully pressed.

8 . A power tool comprising:
a housing; a motor disposed in the housing; and an electronic module disposed partially within the housing, the electronic module configured to provide a signal indicative of a target speed of the motor, the electronic module comprising:
a circuit board comprising a plurality of conductive pads coupled to a power source and a sense pad coupled to an output signal; and
a variable-speed actuator assembly including an actuator positioned adjacent a side edge of the circuit board and moveable along a movement axis perpendicular to the side edge, a plunger coupled to the actuator and moveable with the actuator along the movement axis, and a conductive wiper secured to the plunger in contact with the circuit board, the wiper having a first leg arranged to slidably engage the sense pad and a second leg arranged to slidably engage at least one of the plurality of conductive pads when the actuator is pressed;
wherein the sense pad is longitudinally aligned with the plurality of conductive pads along an axis that is parallel to the movement axis of the actuator, and wherein the first leg of the wiper is located between the actuator and the second leg, and the sense pad is located between the side edge of the circuit board and the plurality of conductive pads.

9 . The power tool of claim 8 , wherein the plurality of conductive pads is respectively coupled to a plurality of resistors arranged in series with the power source so the plurality of conducive pads outputs a varying voltage level that is coupled to the sense pad via the wiper based on a position of the actuator.

10 . The power tool of claim 8 , wherein the plurality of conductive pads is printed on the circuit board as a metal layer including a plurality of gaps therebetween exposing the circuit board.

11 . The power tool of claim 8 , further comprising an end pad disposed between the plurality of conductive pads and the sense pad, wherein the end pad outputs a voltage level different from the plurality of conductive pads.

12 . The power tool of claim 11 , wherein the actuator is biased away from the circuit board to position the second leg of the wiper on the end pad in a default position of the actuator, and wherein movement of the second leg of the wiper from the end pad to the plurality of conducive pads produces a voltage variation indicative of an initial actuation of the actuator.

13 . The power tool of claim 11 , wherein a distance between the end pad and the plurality of conductive pads is smaller than a distance between the end pad and the sense pad but greater than a distance between the respective ones of the plurality of conductive pads.

14 . The power tool of claim 11 , wherein the plurality of conductive pads comprises a second end pad at a distal end thereof opposite the end pad, wherein the second wiper is arranged to engage the second end pad when the actuator is fully pressed.

Assignees

• Black & Decker Inc

Inventors

• Wachter Eric W
• Ekstrom Erik A
• Hizal Alpay

Classifications

• H05K2201/10151

  Sensor · CPC title

• H05K2201/1009

  Electromotor · CPC title

• H05K2201/10053

  Switch · CPC title

• H05K2201/09663

  Divided layout, i.e. conductors divided in two or more parts · CPC title

• H05K2201/09418

  Special orientation of pads, lands or terminals of component, e.g. radial or polygonal orientation · CPC title