Method for producing a silicon-based timepiece spring

Patent metadata

Field	Value
Publication number	US-2021109483-A1
Application number	US-201817047936-A
Country	US
Kind code	A1
Filing date	Dec 18, 2018
Priority date	Apr 16, 2018
Publication date	Apr 15, 2021
Grant date	—

Abstract

A method for producing a timepiece spring includes the following steps: producing a piece based on silicon, having the desired shape of the timepiece spring; thermally oxidising the piece; deoxidising the piece; annealing the piece in a reducing atmosphere; forming a silicon oxide layer on the piece.

First claim

1 . Method for producing a timepiece spring, comprising the following steps:
a) producing a piece based on silicon, having the desired shape of the timepiece spring or comprising a part having the desired shape of the timepiece spring, b) thermally oxidising the piece, c) deoxidising the piece, d) annealing the piece in a reducing atmosphere, e) forming a silicon oxide layer on the piece.

2 . Method for producing a timepiece spring, comprising the following steps:
a) producing a piece based on silicon, having the desired shape of the timepiece spring or comprising a part having the desired shape of the timepiece spring, b) annealing the piece in a reducing atmosphere, c) thermally oxidising the piece, d) deoxidising the piece, e) forming a silicon oxide layer on the piece.

3 . The method as claimed in claim 1 , wherein step a) comprises an etching operation.

4 . The method as claimed in claim 1 , wherein the thermal oxidation step is carried out at a temperature between 600° C. and 1300° C.

5 . The method as claimed in claim 1 , wherein the deoxidation step comprises an etching operation, a vapour phase etching operation or a dry etching operation.

6 . The method as claimed in claim 1 , wherein the annealing step is carried out at a pressure strictly greater than 50 Torr.

7 . The method as claimed in claim 1 , wherein the annealing step is carried out at a pressure strictly greater than 100 Torr.

8 . The method as claimed in claim 1 , wherein the annealing step is carried out at a pressure lower than or equal to atmospheric pressure.

9 . The method as claimed in claim 1 , wherein the annealing step is carried out at a temperature between 800° C. and 1300° C.

10 . The method as claimed in claim 1 , wherein said reducing atmosphere includes hydrogen.

11 . The method as claimed in claim 10 , wherein said reducing atmosphere also includes an inert gas.

12 . The method as claimed in claim 1 , wherein step e) is carried out by thermal oxidation.

13 . The method as claimed in claim 1 , wherein the silicon is monocrystalline or polycrystalline.

14 . The method as claimed in claim 1 , wherein the timepiece spring is a mainspring, a hammer spring, a lever spring, a rocker spring, a pawl spring, a jumper spring, a hairspring or a flexible guide.

15 . The method as claimed in claim 1 , wherein step a) comprises a deep reactive etching operation.

16 . The method as claimed in claim 1 , wherein the thermal oxidation step is carried out at a temperature between 800° C. and 1200° C.

17 . The method of claim 5 , wherein the deoxidation step comprises a wet etching operation.

18 . The method of claim 11 , wherein the inert gas is argon.

19 . The method of claim 14 , wherein the timepiece spring is a mainspring in the form of a barrel spring.

20 . The method as claimed in claim 2 , wherein step a) comprises an etching operation.

Assignees

• Patek Philippe Sa Geneve

Inventors

• Jeanneret Sylvain
• Maier Frédéric
• Bucaille Jean-Luc

Classifications

• G04F7/0804

  with reset mechanisms · CPC title

• G04B1/145 Primary

  Composition and manufacture of the springs (compositions and manufacture of components, wheels, spindles, pivots, or the like G04B13/02; compositions of component escapements G04B15/14; composition and manufacture or hairsprings G04B17/066; compensation for the effects of variations of temperature of springs using alloys, especially for hairsprings G04B17/227; materials for bearings of clockworks G04B31/00; heat treatment and chemical or mechanical treatment for control of the structure C21D8/00; iron and steel alloys C22C; non-ferrous alloys C22C and B22F) · CPC title

• G04D3/0089

  for components of the regulating mechanism, e.g. coil springs · CPC title

• G04B21/06

  Details of striking mechanisms, e.g. hammer, fan governor {(escapements in general G04B15/00; mechanisms for stabilising frequency G04B17/00; resistance regulators G05D13/00; mechanical toys A63H)} · CPC title

• G04B17/066

  Manufacture of the spiral spring (locking of the spiral spring by the regulating lever G04B18/026; spiral spring with temperature compensation G04B17/227; fixation of the spiral spring on the collet G04B17/32; mainspring G04B1/14) · CPC title