Timepiece movement including an analogue display drive device

Patent metadata

Field	Value
Publication number	US-9557714-B2
Application number	US-201615069087-A
Country	US
Kind code	B2
Filing date	Mar 14, 2016
Priority date	Mar 19, 2015
Publication date	Jan 31, 2017
Grant date	Jan 31, 2017

Abstract

Timepiece movement including a date display drive device formed of a display disc including a toothing, said drive device including driving means and a drive source. The driving means includes a wheel set including pins, having a toothed wheel and a pinion including pins, and an engaging wheel engaging said toothed wheel. The pinion with pins includes a pair of pins configured to be positioned on either side of any tooth of the toothing. The toothed wheel of the pin wheel and the engaging wheel respectively have complementary non-circular profiles. When the two pins are oriented in a tangential direction to the toothing, these two wheels have a first gear ratio that is lower than a second gear ratio between them when the two pins are in perpendicular alignment to said tangential direction.

First claim

What is claimed is:

1. A timepiece movement comprising a device for driving an analogue display formed by a display disc including a toothing, the drive device including a drive source and driving means coupling said drive source to the toothing, said drive device including a wheel set including pins, formed of a toothed wheel and of a pinion including pins, and an engaging wheel engaging said toothed wheel, the pin pinion including two diametrically opposite pins separated by a distance configured to position said pins on either side of any tooth of said toothing, wherein said toothed wheel has a first non-circular profile and said engaging wheel has a second non-circular profile which is complementary to the first non-circular profile, and wherein the toothed wheel and the engaging wheel are arranged with respect to each other such that, when said two pins are oriented in a tangential direction to said toothing, said two wheels have a first gear ratio which is lower than a second gear ratio between said wheels when said two pins are in perpendicular alignment to said tangential direction.

2. The timepiece movement according to claim 1 , wherein, when said two pins are oriented substantially tangentially to said display disc toothing, said two pins are arranged to define a self-locking system in the event that the timepiece movement is subjected to a shock exerting a tangential force on said toothing.

3. The timepiece movement according to claim 1 , wherein the pin pinion is configured with respect to the display disc toothing so as to have a dead angle area for driving the display disc, and wherein the angular distance of the dead angle area is greater than ten degrees.

4. The timepiece movement according to claim 3 , wherein, in the event of a shock, said two pins of the pin pinion block the rotation of the display disc when the angular position of the pin pinion is inside the dead angle area.

5. The timepiece movement according to claim 3 , wherein a gear reduction ratio between the engaging wheel and the pin wheel set is greater inside the dead angle area than outside said dead angle area.

6. The timepiece movement according to claim 3 , wherein at least one additional display wheel of the drive device includes an additional display element, said additional display element being able to operate inside the dead angle area without changing the position of the display disc.

7. The timepiece movement according to claim 6 , wherein the additional display wheel is configured to be able to effect a rotation of at least 360° during an angular motion inside the dead angle area.

8. The timepiece movement according to claim 6 , wherein the additional display element is a hand mounted on an arbor of the additional display wheel.

9. The timepiece movement according to claim 8 , wherein the additional display wheel forms a chronograph mechanism.

10. The timepiece movement according to claim 3 , wherein the timepiece movement further comprises a jumper for positioning the display disc, said jumper being arranged to hold the display disc in a plurality of distinct display positions.

11. The timepiece movement according to claim 10 , wherein a substantially identical tangential gear backlash is provided, when the display disc is in any one of said plurality of distinct display positions, between said two tangentially oriented pins and a corresponding tooth of said toothing which is inserted between said two pins.

12. The timepiece movement according to claim 1 , wherein the drive source is formed by a bidirectional electric motor controlled by an electronic unit of the timepiece movement.

13. The timepiece movement according to claim 1 , wherein the display disc is a date ring.

14. The timepiece movement according to claim 6 , wherein the drive source is formed by a bidirectional electric motor controlled by an electronic unit of the timepiece movement.

15. The timepiece movement according to claim 6 , wherein the display disc is a date ring.

Assignees

• Eta Sa Mft Horlogere Suisse

Inventors

• Gruenig Daniel
• Kraehenbuehl David Benjamin
• Winkler Pascal
• Altenhoven Thierry

Classifications

• G04B13/002

  where rotation in one direction is changed into a stepping movement · CPC title

• G04B19/253 Primary

  Driving or releasing mechanisms · CPC title

• G04C17/0066

  electromagnetically driven, e.g. intermittently (clocks incorporating a stepping motor G04C3/14) · CPC title

• G04B13/001

  with the choice of adjustable or varying transmission ratio · CPC title

• G04C17/005 Primary

  by discs (by drums G04C17/0075) · CPC title