Timepiece wheel with play take-up

Patent metadata

Field	Value
Publication number	US-10078308-B2
Application number	US-201715420735-A
Country	US
Kind code	B2
Filing date	Jan 31, 2017
Priority date	Feb 19, 2016
Publication date	Sep 18, 2018
Grant date	Sep 18, 2018

Abstract

Timepiece wheel with play take-up, including a toothing, each tooth of which includes first and second half-teeth each including a part of the tooth profile, and movable with respect to each other against elastic return means, the wheel including, axially stacked, a first and a second half-wheel respectively carrying the first and second half-teeth and having limited rotational mobility with respect to each other, about the axis of this toothing, and against the elastic return means, the toothing of each half-wheel overhanging the other half-wheel, each half-wheel including hollows inside each of which is movable an opposite half-tooth, between two successive half-teeth.

First claim

What is claimed is:

1. A composite timepiece wheel with play take-up, comprising:
a peripheral toothing, each tooth of which includes, on either side of a median part thereof, a first half-tooth including a first part of a tooth profile, and a second half-tooth including a second part of the tooth profile, each said first half-tooth being movable with respect to said second half-tooth of the same said tooth, against elastic return means tending to move said first half-tooth and said second half-tooth of the same said tooth away from each other,
wherein said wheel includes, axially stacked, a first half-wheel carrying all said first half-teeth, and a second half-wheel carrying all said second half-teeth, said first half-wheel and said second half-wheel having limited rotational mobility with respect to each other, about an axis of said toothing, and against said elastic return means,
wherein said first half-wheel includes first hollows between each of said first half-teeth, and each second half-tooth of said second half-teeth of the second half-wheel extends into the first hollows such that each second half-tooth extends between two first successive half-teeth in a rotational plane of the first half-wheel, and
wherein said second half-wheel includes second hollows between each of said second half-teeth, and each first half-tooth of said first half-teeth of the first half-wheel extends into the second hollows such that each first half-tooth extends between two successive second half-teeth in a rotational plane of the second half-wheel.

2. The timepiece wheel according to claim 1 , wherein said first half-wheel comprises a first bearing surface arranged to cooperate in abutment, either with a second opposing bearing surface comprised in said second half-wheel, or with a spacer captively mounted between said first bearing surface and said second bearing surface.

3. The timepiece wheel according to claim 2 , wherein said first half-teeth of said first half-wheel extend on either side of said first bearing surface and of said second bearing surface, and said second half-teeth of said second half-wheel also extend on either side of said first bearing surface and of said second bearing surface.

4. The timepiece wheel according to claim 2 , wherein said first bearing surface and/or said second bearing surface comprises at least one rib, arranged to minimise a contact surface with the opposing half-wheel.

5. The timepiece wheel according to claim 2 , wherein said first bearing surface and/or said second bearing surface comprises a self-lubricating coating of polytetrafluoroethylene or polyundecanamide, arranged to minimise friction with the opposing half-wheel.

6. The timepiece wheel according to claim 1 , wherein said elastic return means comprise at least one spring, on at least said first half-wheel or said second half-wheel, said at least one spring being arranged to cooperate with a pin, carried by the half-wheel opposing that carrying said spring.

7. The timepiece wheel according to claim 6 , wherein said spring is in one piece with the half-wheel that carries said spring.

8. The timepiece wheel according to claim 6 , wherein said spring is pre-wound, arranged, in a rest position of said wheel without mesh with another external component, to hold each said first half-tooth and each said second half-tooth, together forming one said tooth, at a distance from each other.

9. The timepiece wheel according to claim 6 , wherein said pin is in one piece with the half-wheel that carries said pin.

10. The timepiece wheel according to claim 1 , wherein at least said first half-wheel or said second half-wheel is made of micromachinable material or of nickel-phosphorus or of silicon or of silicon oxide or of DLC.

11. A timepiece gear train comprising:
at least one said wheel according to claim 1 , and
a complementary wheel whose toothing cooperates both with said first half-teeth and with said second half-teeth, the air gap between said wheel and said complementary wheel being adjusted so that play between each first half-tooth and each second half-tooth of a tooth in a meshing position is less than the play in rest position in the absence of any complementary wheel between said first half-tooth and said second half-tooth.

12. The timepiece gear train according to claim 11 ,
wherein said wheel comprises said elastic return means including a spring fixed on said first half-wheel which is arranged to carry a hand, said spring exerting a resistance torque on said second half-wheel,
wherein said complementary wheel is a third wheel,
wherein said wheel is an indirect small seconds wheel, said second half-wheel freely swivelling on an arbour of said first half-wheel, and
wherein said spring comprises a beak co-operating with the teeth of said second half-wheel, in order to compensate gear play.

13. A timepiece movement comprising:
at least one timepiece train according to claim 11 .

14. A watch comprising:
the timepiece movement according to claim 13 .

Assignees

• Blancpain Sa

Inventors

• Feyer Julien

Classifications

• G04B35/00 Primary

  Adjusting the gear train, e.g. the backlash of the arbors, depth of meshing of the gears {(adjusting the escapement G04B15/12)} · CPC title

• G04B15/14 Primary

  Component parts or constructional details, e.g. construction of the lever or the escape wheel {(assembly and manufacture of the spring G04B1/145; assembly and manufacture of components, e.g. pinions, spindles G04B13/02; lubrication of clockwork bearings G04B31/008; oils for clockwork bearings in general G04B31/08)} · CPC title

• G04B13/027

  planar toothing: shape and design (adjusting the backlash of the arbors G04B35/00) · CPC title

• G04B13/025 Primary

  with elastic means between the toothing and the hub of a toothed wheel · CPC title

• F16H55/18 Primary

  Special devices for taking up backlash {(for gears having orbital motion F16H1/2863)} · CPC title