Powered ratcheting torque wrench

Patent metadata

Field	Value
Publication number	US-10625405-B2
Application number	US-201715703766-A
Country	US
Kind code	B2
Filing date	Sep 13, 2017
Priority date	Sep 13, 2016
Publication date	Apr 21, 2020
Grant date	Apr 21, 2020

Abstract

A power tool includes a housing defining a grip portion, a motor having a motor drive shaft, a drive assembly coupled to the motor drive shaft and driven by the motor, an output assembly coupled to the drive assembly and having an output member that receives torque from the drive assembly, causing the output member to rotate about an axis, and a transducer assembly disposed between the grip portion and the output assembly to measure the amount of torque applied through the output member, when the motor is deactivated, in response to the power tool being manually rotated about the axis.

First claim

What is claimed is:

1. A power tool comprising:
a housing defining a grip portion;
a motor having a motor drive shaft;
a drive assembly coupled to the motor drive shaft and driven by the motor;
an output assembly coupled to the drive assembly and having an output member that receives torque from the drive assembly, causing the output member to rotate about an axis; and
a transducer assembly disposed between the grip portion and the output assembly to measure the amount of torque applied through the output member, when the motor is deactivated, in response to the power tool being manually rotated about the axis,
wherein the transducer assembly includes a frame configured to bend in response to a tightening operation in which the power tool is manually rotated about the axis of the output member or the output member receives torque from the drive assembly while the grip portion is prevented from rotating about the rotational axis of the output member,
wherein in response to the bending of the frame, the transducer assembly measures the amount of torque applied through the output member during the tightening operation,
wherein the drive assembly includes a crankshaft for transferring torque from the motor drive shaft to the output member, the crankshaft passing along the frame,
wherein when the tightening operation is not being performed, the crankshaft is coaxial with a second axis perpendicular with the rotational axis of the output member, and
wherein at least a portion of the crankshaft is configured to deviate from the second axis in response to bending of the frame.

2. The power tool of claim 1 , wherein the motor drive shaft is rotatable about a first axis, and wherein the axis about which the power tool is rotated is a second axis perpendicular to the first axis.

3. The power tool of claim 1 , wherein the output assembly includes a ratchet mechanism, of which the output member is a component, operated by the drive assembly.

4. The power tool of claim 3 , wherein the ratchet mechanism includes a yoke, and wherein the drive assembly includes a crankshaft for providing an oscillating input to the yoke for intermittently rotating the output member in a first rotational direction about the axis.

5. The power tool of claim 4 , wherein the ratchet mechanism is adjustable for intermittently rotating the output member in a second rotational direction about the axis in response to the oscillating input provided to the yoke.

6. The power tool of claim 4 , wherein the output member is rotationally locked by the yoke when the motor is deactivated and when the power tool is manually rotated about the axis.

7. The power tool of claim 1 , wherein the transducer assembly is disposed between the motor and the output assembly.

8. The power tool of claim 1 , further comprising:
a housing in which the motor is at least partly disposed; and
a head in which the output assembly is at least partly received, wherein the drive assembly extends from the housing toward the head.

9. The power tool of claim 8 , wherein the transducer assembly includes a frame interconnecting the housing and the head.

10. The power tool of claim 9 , wherein the frame is integrally formed with the head.

11. The power tool of claim 9 , wherein the frame includes a beam extending between first and second mounts located, respectively, on opposite ends of the beam.

12. The power tool of claim 11 , wherein the first mount is attached to the housing, and wherein the second mount is attached to the head.

13. The power tool of claim 11 , wherein the beam is a first beam, and wherein the frame further includes a second beam extending between the first and second mounts.

14. The power tool of claim 13 , wherein the first beam and the second beam are parallel and offset from each other, thereby defining a gap between the first and second beams.

15. The power tool of claim 14 , wherein the drive assembly includes a shaft disposed between the first and second beams, and within the gap.

16. The power tool of claim 15 , wherein the shaft includes a universal joint disposed within the gap.

17. The power tool of claim 9 , wherein the frame includes a beam, and wherein the transducer assembly includes a sensor coupled to the beam for detecting strain in response to a bending force applied to the beam.

18. The power tool of claim 17 , wherein the sensor is a strain gauge.

19. The power tool of claim 17 , wherein the beam is a first beam and the sensor is a first sensor, wherein the frame includes a second beam parallel to the first beam, and wherein the transducer assembly includes a second sensor coupled to the second beam for detecting strain in response to a bending force applied to the second beam.

20. The power tool of claim 1 , further comprising a display device to indicate the amount of torque applied through the output member when the power tool is manually rotated about the axis.

21. The power tool of claim 20 , wherein the display device includes a visual indicator to communicate to a user when the applied torque reaches or exceeds a pre-defined torque setting.

22. The power tool of claim 21 , wherein the visual indicator flashes in response to the pre-defined torque setting being reached when the power tool is manually rotated about the axis.

23. The power tool of claim 21 , wherein the display device includes at least one input device for adjusting the pre-defined torque setting.

24. The power tool of claim 1 , further comprising a battery pack for providing power to the motor when activated, wherein the transducer assembly receives power from the battery pack, when the motor is deactivated, to measure the amount of torque applied through the output member in response to the power tool being manually rotated about the axis.

25. The power tool of claim 24 , further comprising a display device that also receives power from the battery pack, when the motor is deactivated, to indicate the amount of torque applied through the output member in response to the power tool being manually rotated about the axis.

26. The power tool of claim 1 , wherein the crankshaft is one of a single flexible shaft that flexes in response to bending of the frame, or a multiple-piece crankshaft having first and second shaft portions connected by a joint configured to permit selective misalignment between the first and second shaft portions in response to bending of the frame.

27. The power tool of claim 26 , wherein the joint is a universal joint configured to permit rotation of the first shaft portion about a longitudinal axis that is non-collinear with the second axis.

Assignees

• Milwaukee Electric Tool Corp

Inventors

• Silha Wyatt R
• Schneider Jacob P
• Dey Iv John S
• Banholzer Hans T

Classifications

• B25B23/1456

  having electrical components · CPC title

• B25B23/147

  specially adapted for electrically operated wrenches or screwdrivers · CPC title

• B25B13/46

  of the ratchet type, for providing a free return stroke of the handle · CPC title

• B25B23/1425 Primary

  by electrical means · CPC title

• B25B13/10

  with adjustable jaws (B25B13/46, B25B13/48 {B25B13/5041} take precedence) · CPC title