Handheld power tool with compact AC switch

Patent metadata

Field	Value
Publication number	US-9559628-B2
Application number	US-201314063503-A
Country	US
Kind code	B2
Filing date	Oct 25, 2013
Priority date	Oct 25, 2013
Publication date	Jan 31, 2017
Grant date	Jan 31, 2017

Abstract

A power tool is disclosed having a compact AC switch assembly. An electric motor driving the power tool is contained within a housing that includes a handle. A trigger is slidingly received in the handle and moves in an axis of trigger travel along a trigger travel distance extending between an extended position of the trigger and a depressed position. A trigger switch including a printed circuit board is disposed in mechanical communication with the trigger and controls the electric motor in accordance with trigger position. The printed circuit board has a plurality of conductive traces that are sequentially arranged and linearly aligned adjacent the trigger in a direction that is transverse to the axis of trigger travel to reduce the width of the printed circuit board to a value that is less than or equal to three times the trigger travel distance.

First claim

What is claimed is:

1. A power tool having a compact AC switch assembly, comprising:
an electric motor;
a housing containing said electric motor and including a handle;
a trigger slidingly received in and at least partially extending through said handle that moves along an axis of trigger travel between an extended position and a depressed position;
said trigger defining a trigger travel distance extending from said extended position to said depressed position;
a trigger switch attached to said trigger to control said electric motor in accordance with position of said trigger in relation to said trigger switch; and
said trigger switch including a printed circuit board having a width extending along said axis of trigger travel wherein said width of said printed circuit board equals a value that is less than or equal to three times said trigger travel distance;
wherein said printed circuit board includes an input connection configured to receive electricity and an output connection configured to supply electricity to said electric motor and a plurality of conductive traces electrically connecting said input connection and said output connection, said plurality of conductive traces being sequentially arranged and linearly aligned adjacent said trigger in a direction transverse to said axis of trigger travel to reduce said width of said printed circuit board.

2. A power tool having a compact AC switch assembly as set forth in claim 1 wherein said plurality of conductive traces are made of a copper and silver alloy to prevent electrical arcing between said sequentially arranged conductive traces.

3. A power tool having a compact AC switch assembly as set forth in claim 1 further including a heat sink plate thermally coupled to said printed circuit board wherein said heat sink plate is made of copper.

4. A power tool having a compact AC switch assembly as set forth in claim 1 wherein said trigger travel distance is greater than or equal to 35 percent of said width of said printed circuit board.

5. A power tool having a compact AC switch assembly as set forth in claim 1 wherein said trigger travel distance is greater than or equal to 40 percent of said width of said printed circuit board.

6. A power tool having a compact AC switch assembly as set forth in claim 1 wherein said trigger switch includes a variable resistor mounted on said printed circuit board along said axis of trigger travel and electrically connected to said plurality of conductive traces.

7. A power tool having a compact AC switch assembly as set forth in claim 6 wherein said variable resistor is disposed in sliding engagement with said trigger to control said electric motor in accordance with position of said trigger in relation to said trigger switch.

8. A power tool having a compact AC switch assembly as set forth in claim 7 wherein said variable resistor has an outboard end corresponding with said extended position of said trigger and an inboard end corresponding with said depressed position of said trigger and a predetermined length extending between said outboard end and said inboard end being greater than or equal to said trigger travel distance.

9. A power tool having a compact AC switch assembly as set forth in claim 8 wherein said plurality of conductive traces of said printed circuit board are sequentially arranged and linearly aligned adjacent said inboard end of said variable resistor to reduce said width of said printed circuit board.

10. A power tool having a compact AC switch assembly as set forth in claim 9 wherein said width of said printed circuit board equals a value that is less than or equal to two times said predetermined length of said variable resistor.

11. A power tool having a compact AC switch assembly as set forth in claim 10 wherein said trigger switch includes a triac mounted to said printed circuit board and electrically connected to said output connection and a current shock resistor mounted to said printed circuit board and electrically connected to said input connection and said triac.

12. A power tool having a compact AC switch assembly as set forth in claim 11 further including an AC power cord extending through said housing and being electrically connected to said input connection of said printed circuit board.

13. A power tool having a compact AC switch assembly as set forth in claim 11 further including:
a diac mounted to said printed circuit board and electrically connected to said variable resistor and said triac;
a double diode mounted to said printed circuit board and electrically connected to said variable resistor;
a capacitor mounted to said printed circuit board and electrically connected to said variable resistor and said diac; and
at least one resistor mounted to said printed circuit board and electrically connected to said variable resistor and said double diode.

14. A power tool having a compact AC switch assembly as set forth in claim 9 further including a trigger switch cover housing said trigger switch and having a pin connector mounted to said printed circuit board and configured to connect with a microprocessor that digitally controls said electric motor.

15. A power tool having a compact AC switch assembly as set forth in claim 9 further including a motor direction selector movably received in said handle that moves between a forward position and a reverse position corresponding to a direction of rotation of said electric motor.

16. A power tool having a compact AC switch assembly as set forth in claim 9 further including a trigger lock movably received in said handle that moves between a locked position and an unlocked position wherein said trigger lock engages said trigger in said locked position to limit movement of said trigger along said axis of trigger travel.

17. A power tool having a compact AC switch assembly as set forth in claim 9 further including a driven shaft coupled to said electric motor wherein said driven shaft presents an end configured to receive a tool.

18. A power tool having a compact AC switch assembly as set forth in claim 17 wherein the handheld power tool is a jigsaw and said driven shaft has an end configured to receive a saw blade and drive the saw blade in a reciprocating motion.

19. A power tool having a compact AC switch assembly as set forth in claim 18 further including a shoe pivotally connected to said housing wherein said shoe presents a bottom surface facing away from said housing that is configured to abut a work piece.

20. A power tool having a compact AC switch assembly as set forth in claim 17 wherein the handheld power tool is a drill and said driven shaft has an end configured to receive a bit and drive the bit rotationally.

21. A power tool having a compact AC switch assembly as set forth in claim 17 wherein the handheld power tool is a sander and said driven shaft has an end configured to drive a sanding pad.

22. A power tool having a compact AC switch assembly, comprising:
A driven shaft having an end configured to receive a tool;
an electric motor having a direction of rotation and a plurality of motor speeds, said electric motor being coupled to said driven shaft to drive said driven shaft;
a housing containing said electric motor and including a handle;
a trigger slidingly received in and extending at least partially through said handle to provide movement between an extended position and a depressed position and a plurality of positions therebetween each corresponding to said plurality

Assignees

• Black & Decker Inc

Inventors

• Sergyeyenko Oleksiy P
• French Timothy W
• Martinez Phillip
• Wang Yesman

Classifications

• B25F5/00

  Details or components of portable power-driven tools not particularly related to the operations performed and not otherwise provided for · CPC title

• H02P1/02 Primary

  Details {of starting control} · CPC title

• H02P27/00 Primary

  Arrangements or methods for the control of AC motors characterised by the kind of supply voltage (of two or more motors H02P5/00; of synchronous motors with electronic commutators H02P6/00; of DC motors H02P7/00; of stepping motors H02P8/00) · CPC title

• B25F5/02

  Construction of casings, bodies or handles {(B25F5/006, B25F5/008 take precedence)} · CPC title

• H02K11/28 Primary

  Manual switches · CPC title