Assembly system utilising a conical, elastic locking element

Patent metadata

Field	Value
Publication number	US-9488961-B2
Application number	US-201414504550-A
Country	US
Kind code	B2
Filing date	Oct 2, 2014
Priority date	Oct 9, 2013
Publication date	Nov 8, 2016
Grant date	Nov 8, 2016

Abstract

An assembly system includes a member made of a first material including a staff and a shoulder, the staff of the member being received in an aperture of a part made of a second material having little or no plastic domain. The assembly system includes a locking element made of a third material arranged to elastically attach the part between the shoulder of the member and the locking element, and the locking element is a conical washer including an internal wall which radially grips the staff of the member. A peripheral portion of the locking element exerts an elastic radial force vertical to the shoulder of the member in order to secure assembly of the member, the part, and the locking element.

First claim

What is claimed is:

1. An assembly system comprising:
a member made of at least a first material including a staff and a shoulder, the staff of the member being received in an aperture of a part made of a silicon-based material, wherein
the assembly system includes a locking element made of a metal or a metal alloy arranged to elastically attach the part made of the silicon-based material between the shoulder of the member and the locking element, and wherein
the locking element is a washer having an internal wall including a substantially straight portion over part of a height of the locking element which radially grips the staff of the member, the internal wall including, adjacent to the substantially straight portion, a portion which flares conically towards the part made of the silicon-based material so that only a peripheral portion of the locking element exerts an axial elastic force vertical to the shoulder of the member so as to secure assembly of the member, the part made of the silicon-based material, and the locking element.

2. The assembly system according to claim 1 , wherein the metal or the metal alloy of the locking element includes a resistance to relaxation, after 10,000 hours at a temperature of 70° C. equal to at least 50% of an applied force representing 75% of a stress necessary to obtain 0.2% plastic deformation of the metal or the metal alloy of the locking element in order to maintain the secure assembly of the member, the part made of the silicon-based material, and the locking element.

3. The assembly system according to claim 2 , wherein the metal or the metal alloy of the locking element includes copper, brass, nickel silver, ARCAP alloy, Pfinodal alloy, Spinodal alloy, Durnico alloy, Durimphy alloy, Cu—Be alloy and/or 20AP steel.

4. The assembly system according to claim 1 , wherein a ratio of height to width of the locking element in cross-section in an axial plane is between 0.1 and 5.

5. The assembly system according to claim 1 , wherein a ratio of a height of the flared portion to a total height of the locking element in cross-section in an axial plane is between 0.1 and 0.95.

6. The assembly system according to claim 1 , wherein a ratio of a width of the flared portion to a total width of the locking element in cross-section in an axial plane is between 0.1 and 0.95.

7. The assembly system according to claim 1 , wherein the internal wall includes a second portion which flares conically away from the part made of the silicon-based material and which is symmetrical to the portion which flares conically towards the part made of the silicon-based material with respect to the substantially straight portion.

8. The assembly system according to claim 1 , wherein the locking element is chamfered to prevent any breakage of the silicon-based material.

9. The assembly system according to claim 1 , wherein the silicon-based material includes silicon, quartz, silicon oxide, silicon nitride or silicon carbide.

10. The assembly system according to claim 1 , wherein the at least the first material includes a metal or a metal alloy.

11. The assembly system according to claim 1 , wherein the staff and the shoulder are in a single piece.

12. A timepiece wherein the timepiece includes at least one assembly system according to claim 1 .

13. The timepiece according to claim 12 , wherein the part made of the silicon-based material is a wheel set, pallets or a balance spring.

14. A method of manufacturing an assembly system comprising:
forming a member made of at least a first material including a staff and a shoulder, a part made of a silicon-based material with an aperture, and a locking element in the form of a washer based on a metal or a metal alloy, the locking element including a hole which is smaller than the staff of the member and whose internal wall has a substantially straight portion over part of a height of the locking element and a portion which flares conically away from the substantially straight portion;
passing the staff of the member freely into the aperture of the part made of the silicon-based material;
placing the staff against the hole in the locking element, the flared portion facing the part made of the silicon-based material, and forcibly sliding the locking element against the staff by applying a force using a tool to elastically deform the locking element in the substantially straight portion of the internal wall thereof so that a peripheral portion of the locking element is the closest to the part; and
stopping, then removing the tool when a predefined force less than a yield strength of the metal or the metal alloy of the locking element is reached between the tool and the shoulder of the member such that only the peripheral portion of the locking element exerts an axial elastic force vertical to the shoulder of the member so as to secure assembly of the member, the part made of the silicon-based material, and the locking element.

15. The method according to claim 14 , wherein the stopping is stopped when the force applied by the tool iso comprised between 20% and 90% of the yield strength of the metal or the metal alloy of the locking element.

16. The method according to claim 14 , wherein the metal or the metal alloy of the locking element includes a resistance to relaxation, after 10,000 hours at a temperature of 70° C. equal to at least 50% of the force applied in the stopping representing 75% of a stress necessary to obtain 0.2% plastic deformation of the metal or the metal alloy of the locking element in order to maintain the secure assembly of the member, the part made of the silicon-based material, and the locking element.

17. The method according to claim 16 , wherein the metal or the metal alloy includes copper, brass, nickel silver, ARCAP alloy, Pfinodal alloy, Spinodal alloy, Durnico alloy, Durimphy alloy, Cu—Be alloy and/or 20AP steel.

18. The method according to claim 14 , wherein a ratio of height to width of the locking element in cross-section in an axial plane is between 0.1 and 5.

19. The method according to claim 14 , wherein a ratio of a height of the flared portion to a total height of the locking element in cross-section in an axial plane is between 0.1 and 0.95.

20. The method according to claim 14 , wherein a ratio of a width of the flared portion to a total width of the locking element in cross-section in an axial plane is between 0.1 and 0.95.

21. The method according to claim 14 , wherein the internal wall of the locking element includes a second portion which flares conically away from the substantially straight portion and which is symmetrical to the portion which flares conically away from the substantially straight portion with respect to the substantially straight portion.

22. The method according to claim 14 , wherein the locking element is chamfered to prevent any breakage of the silicon-based material.

23. The method according to claim 14 , wherein the silicon-based material includes silicon, quartz, silicon oxide, silicon nitride or silicon carbide.

24. The method according to claim 14 , wherein the at least the first material includes a metal or a metal alloy.

25. The method according to claim 14 , wherein the part made of the silicon-based material is a timepiece wheel set.

26. The method according to claim 14 , wherein the part made of the silicon-based material is pallets of a timepiece.

27. The method a

Assignees

• Nivarox Far Sa

Inventors

• Stranczl Marc
• Mallet Daniel
• Verardo Marco

Classifications

• Y10T29/49826

  Assembling or joining · CPC title

• G04B15/14

  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

• Y10T403/4933

  by separate, deformable element · CPC title

• Y10T29/49581

  having arbor, pinion, or balance · CPC title

• Y10T29/49579

  Watch or clock making · CPC title