Return mechanism for a cordless nailer

Patent metadata

Field	Value
Publication number	US-10654155-B2
Application number	US-201715630044-A
Country	US
Kind code	B2
Filing date	Jun 22, 2017
Priority date	Jun 30, 2016
Publication date	May 19, 2020
Grant date	May 19, 2020

Abstract

A driver return assembly can be positioned to return a concrete nail driver of a cordless electric powered nailer to the home position. A return rack can be fixedly coupled to and positioned along a longitudinal length of the concrete nail driver The driver return assembly can include a solenoid driving a plunger in a reciprocating motion in a homeward direction and a driven direction. A return pawl can be coupled to the plunger and pivotable into a pawl raised position relative to the plunger in which the pawl is engageable with the return rack during movement of the plunger in the homeward direction, and pivotable into a pawl lowered position relative to the plunger in which the pawl is not engageable with the return rack during movement of the plunger in the driven direction.

First claim

What is claimed is:

1. A cordless electric nailer comprising:
a power take-off assembly positioned and operable to selectively engage a pinch roller against a nail driver having a home position to pinch the nail driver against a battery-powered electric motor driven flywheel and fire the nail driver along a driver axis;
a return rack fixedly coupled to and positioned along a longitudinal length of the nail driver; and
a driver return assembly positioned to engage and return the nail driver to the home position, the driver return assembly including:
a return motor operably coupled to a return pawl to alternatingly drive the return pawl along a pawl axis that is parallel to the driver axis in a homeward direction while the return pawl is in a raised position in which the return pawl is engageable with the return rack to drive the nail driver along the driver axis toward the home position, and drive the return pawl along the pawl axis in a driven direction opposite the homeward direction while the return pawl is in a lowered position in which the return pawl is not engageable with the return rack.

2. The cordless electric nailer of claim 1 , wherein the return pawl is coupled to a component of the return motor via a pivot pin and the return pawl is pivotable about the pivot pin away from the return motor component into the raised position, and pivotable about the pin toward the return motor component into the lowered position.

3. The cordless electric nailer of claim 2 , wherein the return motor comprises a solenoid and the return motor component comprises a solenoid plunger.

4. The cordless electric nailer of claim 3 , wherein the pivot pin extends through a distal end of the solenoid plunger.

5. The cordless electric nailer of claim 1 , wherein the homeward direction and the driven direction along which the return pawl alternatingly travels each comprise a linearly extending direction.

6. The cordless electric nailer of claim 1 , wherein the return motor comprises a solenoid including a biasing member biasing a plunger toward an extended position, and a bumper positioned to engage and stop the plunger in a retracted position.

7. The cordless electric nailer of claim 6 , wherein the bumper is a foam bumper.

8. The cordless electric nailer of claim 1 , wherein the return motor comprises a solenoid including a plunger and wherein the plunger moves in the homeward direction as the plunger moves toward a retracted position, and wherein the plunger moves in the driven direction as the plunger moves toward the extended position.

9. The cordless electric nailer of claim 1 , wherein the power take-off assembly and the nail driver return assembly are both positioned on a same side of the nail driver.

10. The cordless electric nailer of claim 1 , wherein the return rack is disposed at an upper end of the nail driver, which upper end is opposite the driving end of the nail driver.

11. The cordless electric nailer of claim 1 , wherein the cordless electric nailer is a concrete nailer.

12. A cordless electric concrete nailer comprising:
a power take-off assembly positioned and operable to selectively engage a pinch roller against a concrete nail driver having a home position to pinch the concrete nail driver against a battery-powered electric motor driven flywheel and fire the concrete nail driver along a driver axis;
a return rack fixedly coupled to and positioned along a longitudinal length of the concrete nail driver; and
a driver return assembly positioned to return the concrete nail driver to the home position, the driver return assembly including:
a solenoid driving a plunger in a reciprocating motion in a homeward direction along a plunger axis parallel to the driver axis and in a driven direction opposite the homeward direction along the plunger axis;
a return pawl operably coupled to the plunger and pivotable into a pawl raised position in which the pawl is engageable with the return rack during movement of the plunger and the pawl along the plunger axis in the homeward direction to drive the concrete nail driver toward the home position, and pivotable into a pawl lowered position in which the pawl is not engageable with the return rack during movement of the plunger and the pawl along the plunger axis in the driven direction.

13. The cordless electric concrete nailer of claim 12 , wherein the driver return assembly further comprises a biasing member biasing the return pawl toward the raised position during of the motion of the plunger in the homeward direction.

14. The cordless electric concrete nailer of claim 12 , wherein the driver return assembly further comprises a magnet biasing the return pawl toward the raised position during of the motion of the plunger in the homeward direction.

15. The cordless electric concrete nailer of claim 12 , wherein the driver return assembly further comprises a magnet assembly including a magnet positioned to pivot the return pawl toward the raised position via a magnetic force of the magnet during the motion in the homeward direction, and a surface positioned to pivot the return pawl toward the lowered position via engagement of the surface with the return pawl during the motion of the plunger in the driven direction.

16. The cordless electric concrete nailer of claim 12 , wherein a surface is positioned to retain the return pawl in the lowered position via engagement of the surface with the return pawl between the reciprocating motion of the plunger.

17. The cordless electric concrete nailer of claim 12 , wherein the rack comprises a series of engagement teeth and the return pawl comprises a cooperating engagement pawl tooth.

18. The cordless electric concrete nailer of claim 17 , wherein a backside of each of the engagement teeth is angled to engage the cooperating engagement pawl tooth to cause movement of the return pawl toward the lowered position as the return pawl disengages from an adjacent one of the engagement teeth.

19. The cordless electric concrete nailer of claim 12 , wherein the plunger moves in the homeward direction as the plunger moves toward a retracted position, and wherein the plunger moves in the driven direction as the plunger moves toward an extended position.

20. The cordless electric concrete nailer of claim 19 , wherein the solenoid includes a biasing member that biases the plunger toward the extended position, and a bumper positioned to engage and stop the plunger in the retracted position.

21. The cordless electric concrete nailer of claim 20 , wherein the bumper is a foam bumper.

22. The cordless electric concrete nailer of claim 12 , wherein the power take-off assembly and the driver return assembly are both positioned on a same side of the nail driver.

23. The cordless electric concrete nailer of claim 22 , wherein the return rack is disposed at an upper end of the nail driver, which upper end is opposite the driving end of the nail driver.

24. The cordless electric concrete nailer of claim 12 , further comprising a circuit configured to successively energize and de-energize the solenoid a predetermined number of cycles after each firing of the concrete nail driver.

25. The cordless electric concrete nailer of claim 24 , wherein the predetermined number of cycles is 5.

26. The cordless concrete nailer of claim 24 , wherein the circuit is further configured to de-energize the solenoid a predetermined period of de-energized time between

Assignees

• Black & Decker Inc

Inventors

• Meyer Jeffrey J
• Garber Stuart E

Classifications

• B25C1/008

  Safety devices · CPC title

• B25C1/06 Primary

  operated by electric power · CPC title