Device for Screwing Without Reaction Force in the Handle

• US 20140096989A1
• Filed: 10/03/2013
• Published: 04/10/2014
• Est. Priority Date: 10/05/2012
• Status: Active Grant

• Current Assignee: Etablissements Georges Renault SAS (Atlas Copco AB)
• Original Assignee: Etablissements Georges Renault SAS (Atlas Copco AB)
• Inventors: Le Du, Nicolas, Limousin, Damien
• Granted Patent: US 9,555,534 B2
• Time in Patent Office: Days
• US Class Current: 173/216
• CPC Class Codes: B25B 21/00 Portable power-driven screw or nut setting or loosening tools; details or components, e.g. casings, bodies, of portable power-driven tools not particularly related to the operation performed B25F5/00; for mounting or dismounting wheels B60B29/006; Attachments for drilling apparatus serving the same purpose machines B23P19/06
• CPC Class Codes: B25B 23/0078 Reaction arms
• CPC Class Codes: B25F 5/001 Gearings, speed selectors, clutches or the like specially adapted for rotary tools
• CPC Class Codes: B25F 5/025 with torque reaction bars for rotary tools

Abstract

A device is provided for screwing. The device includes a handle housing and a gear reduction housing. The handle housing includes a handle and lodges a motor. The gear reduction housing lodges a gear reduction unit, the input of which cooperates with the output of the motor. The gear reduction unit includes a single output cooperating with a rotating end element for cooperating with an element to be screwed. The gear reduction housing is linked to the handle housing by a rotating link. The rotating link is configured in a way such that a negligible reaction force is transmitted to the handle housing during an operation of screwing.

Claims

1. A device for screwing comprising:

a handle housing comprising a handle and lodging a motor; and

a gear reduction housing, said gear reduction housing lodging a gear reduction unit, an input of which cooperating with an output of said motor, said gear reduction unit comprising a single output cooperating with a rotating end element that is configured for cooperating with an element to be screwed, said gear reduction housing being linked to said handle housing by a rotating link, which is configured in a way such that a negligible reaction force is transmitted to said handle housing during an operation of screwing.

2. The device according to claim 1, wherein said rotating link comprises means of transmission, to said handle housing, of a reaction torque having an intensity that is substantially identical, and a direction that is opposite, to that of the reaction torque transmitted by said gear reduction unit to said motor.

3. The device according to claim 2, wherein said gear reduction unit comprises a first epicyclic gear train having a first sun gear interdependent with said motor, first planet gears mounted on a first planet carrier, and a ring gear mounted freely in rotation in said gear reduction housing, said means of transmission comprising a second epicyclic train having a second sun gear mobile in rotation relative to said first sun gear and fixed to said handle housing, second planet gears mounted on a second planet carrier fixed to said gear reduction housing, and said ring gear.

4. The device according to claim 3, wherein the number of gear teeth, respectively of the sun gear, the planet gears and the ring gear of the first epicyclic train are identical to those of the sun gear, the planet gears and the ring gear of the second epicyclic train.

5. The device according to claim 3, wherein the input of the first epicyclic train is said sun gear and its output is said planet carrier, and the input of said second epicyclic train is said sun gear and its output is said planet carrier, and said first and second trains have identical reduction ratios.

6. The device according to claim 3, wherein the first planet carrier is directly connected to the rotating end member.

7. The device according to claim 1, wherein the device comprises at least one torque sensor configured for measuring a piece of information representing a tightening torque of said element to be screwed, said at least one torque sensor being integrated into said means of transmission.

8. The device according to claim 7, wherein said torque sensor is mounted on said second sun gear.

9. The device according to claim 8, wherein said torque sensor integrates strain gauges.

10. The device according to claim 1, wherein the device comprises a gearbox interposed between said motor and said gear reduction unit.

11. The device according to claim 10, wherein the device comprises means for changing speed by inverting a sense of rotation of said motor.

12. The device according to claim 10 wherein the axis of said gearbox and of said gear reduction unit extends in parallel and in a way such that the axis is offset from the axis of said motor.

13. The device according to claim 1, wherein the device comprises a reaction bar interdependent with said gear reduction housing.