JPWO2021083680A5

JPWO2021083680A5 -

Info

Publication number: JPWO2021083680A5
Application number: JP2022524202A
Authority: JP
Publication date: 2023-08-16

Claims

a housing (H);
an input shaft (IS);
an output shaft;
a two-speed power transmission (T);
A power tool comprising
Said two-speed power transmission transmits torque to and through said planetary gear (4) in high torque/low speed drive mode or past said planetary gear (4) in low torque/high speed drive mode. a two-speed gearshift assembly for directing the
The gear shift assembly comprises:
a driving member (2) drivingly coupled to the input shaft;
a driven member (1) drivingly coupled to the output shaft;
so as to interconnect said driving member (2) and said driven member (1) in a first position and interconnect said planetary gear (4) and said driven member (1) in a second position; an axially displaceable coupling sleeve (6) arranged in
a linear actuator (13, 14) arranged to displace said joint sleeve between said first position and said second position;
with
said linear actuator comprises a linearly displaceable push bar (13) arranged to displace said joint sleeve between said first position and said second position;
The gearshift assembly further comprises a joint assembly positioned between the joint sleeve and the linear actuator, the joint assembly having a first element (8) rotatably coupled to the sleeve. wherein rotation of said first element is independent of rotation of said push bar, said push bar arranged to axially push said first element;
A power tool, wherein the coupling sleeve is arranged concentrically with respect to the planetary gear and the push bar is adapted to engage the first element at a position central to the sleeve.

The power tool of claim 1, wherein said first element is a ball disposed at least partially within said sleeve.

3. The claim 1 or 2, wherein a first axially acting spring means (3) is arranged for biasing the coupling sleeve towards the first position of the coupling sleeve. power tools.

The first position and the second position are a first end position and a second end position, the coupling sleeve is continuously movable therebetween, the first end position 4. A power tool according to any one of claims 1 to 3, wherein the power tool can be positioned at any position between the and second end positions.

said driven member comprises a first engagement portion (1b) adapted to engage a corresponding congruent first portion of said coupling sleeve;
2. From claim 1, wherein said planetary gear comprises a planetary gear carrier (41) comprising a second engaging portion (41b) adapted to engage a corresponding congruent second portion of said coupling sleeve. 5. The power tool according to any one of 4.

6. The power tool of claim 5, wherein at least one of the first engaging portion and the second engaging portion has a polygonal cross-section.

7. Any one of claims 1 to 6, further comprising a bevel gear disposed between the input shaft and the drive member, the drive member being coupled to the input shaft via the bevel gear. or the power tool according to item 1.

A power tool according to any preceding claim, wherein the linear actuator is a linear DC servo motor including a solid stator housing, a coil assembly and a multi-pole magnetic pushrod.

A power tool according to any preceding claim, wherein the linear actuator includes at least one internal position sensor configured to sense the position of the push bar.

10. A power tool as claimed in any preceding claim, wherein the planetary gear is a first planetary gear stage.

11. A two-speed power transmission for a power tool according to any one of claims 1 to 10, said transmission comprising planetary gears and, in a high torque/low speed drive mode, through said planetary gears, or a two-speed gearshift assembly for directing torque past said planetary gears in a low torque/high speed drive mode, said gearshift assembly comprising:
a driving member drivingly coupled to the input shaft;
a driven member drivingly coupled to the output shaft;
a coupling sleeve arranged to interconnect the drive member and the driven member at a first position and to interconnect the planet gear carrier and the driven member at a second position;
a linear actuator arranged to displace the coupling sleeve between the first position and the second position;
with
said linear actuator comprising a linearly movable push bar (13) arranged to displace said joint sleeve between said first position and said second position;
The gearshift assembly further comprises a joint assembly positioned between the joint sleeve and the linear actuator, the joint assembly having a first element (8) rotatably coupled to the sleeve. wherein rotation of said first element is independent of rotation of said push bar, said push bar arranged to axially push said first element;
A two-speed power transmission, wherein the coupling sleeve is arranged concentrically with respect to the planetary gear, and the push bar is adapted to engage the first element at a position central to the sleeve. .

A method in a power tool according to any one of claims 1 to 10, comprising:
operating the power tool in a low torque/high speed drive mode of operation in which the coupling sleeve is arranged to direct torque through the planetary gear in a first position;
identifying that a tight fit has been reached;
using the linear actuator to displace the coupling sleeve forward by axial movement in a first direction to reach the second position;
operating the power tool in a high torque/low speed drive mode of operation in which the coupling sleeve is positioned in the second position to direct torque through the planetary gears;
A method, including

Reaching the second position comprises: if the coupling sleeve does not engage the planetary gear;
rearwardly displacing the coupling sleeve by axial movement of the linear actuator in a second opposite direction;
rotating the planetary gear;
axial movement of the linear actuator in the first direction to displace the joint sleeve forward to reach the second position;
13. The method of claim 12, further comprising: