Timepiece mainspring, timepiece drive device, timepiece movement, timepiece, and manufacturing method of timepiece mainspring

Patent metadata

Field	Value
Publication number	US-10317842-B2
Application number	US-201715486766-A
Country	US
Kind code	B2
Filing date	Apr 13, 2017
Priority date	Apr 25, 2016
Publication date	Jun 11, 2019
Grant date	Jun 11, 2019

Abstract

A timepiece mainspring is accommodated inside a barrel, an inner end thereof is fixed to a barrel arbor included in the barrel, and an outer end thereof engages with an inner wall of the barrel. The timepiece mainspring includes a helical portion wound in a Bernoulli curve shape from the inner end in a free state having no applied load.

First claim

What is claimed is:

1. A timepiece mainspring which is accommodated inside a barrel in a loaded state with an arbor end of the mainspring being fixed to a barrel arbor, and a wheel end of the mainspring engaging an inner wall of the barrel, the timepiece mainspring comprising:
a helical body;
a main body; and
a connection link connect the main body and the helical body,
wherein, when the mainspring is in a free state having no applied load, the helical body is wound in a Bernoulli curve shape from the arbor end, the main body is wound counterclockwise to the helical body from the wheel end, and the arbor end is positioned radially outward from the wheel end, and
the number of rolls of the helical portion is 2.5 rolls or more.

2. A timepiece mainspring comprising:
an inner end that is accommodated inside a barrel, and that is fixed to a barrel arbor included in the barrel;
a winding portion that is continuous with the inner end, and that is wound around the barrel arbor;
a helical portion that is continuous with the winding portion; and
an outer end that engages with an inner wall of the barrel,
wherein in a free state having no applied load, the helical portion is wound in a Bernoulli curve shape, and
the number of rolls of the helical portion is 2.5 rolls or more.

3. The timepiece mainspring according to claim 1 , wherein a material of the timepiece mainspring is a nickel cobalt alloy.

4. The timepiece mainspring according to claim 2 , wherein a material of the timepiece mainspring is a nickel cobalt alloy.

5. The timepiece mainspring according to claim 1 , wherein a material of the timepiece mainspring is stainless steel.

6. The timepiece mainspring according to claim 2 , wherein a material of the timepiece mainspring is stainless steel.

7. A timepiece drive device comprising:
the timepiece mainspring according to claim 1 ; and
the barrel that accommodates the timepiece mainspring.

8. A timepiece drive device comprising:
the timepiece mainspring according to claim 2 ; and
the barrel that accommodates the timepiece mainspring.

9. A timepiece movement comprising:
the timepiece drive device according to claim 7 ; and
a gear that is driven by the timepiece drive device.

10. A timepiece movement comprising:
the timepiece drive device according to claim 8 ; and
a gear that is driven by the timepiece drive device.

11. A timepiece comprising:
the timepiece movement according to claim 9 .

12. A timepiece comprising:
the timepiece movement according to claim 10 .

Assignees

• Seiko Epson Corp

Inventors

• Nakata Keisuke
• Takeuchi Masao
• Kobayashi Shogo

Classifications

• G04B1/18 Primary

  Constructions for connecting the ends of the mainsprings with the barrel or the arbor {(mainsprings and bridles therefor G04B1/14; clamping the hairspring on the regulator G04B18/026; clamping the hairspring on the arbor G04B17/32)} · 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

• G04B1/16

  Barrels; Arbors; Barrel axles (arrangements facilitating the removal of the mainspring G04B33/14) · CPC title