WO2017006348A1

WO2017006348A1 - A mechanism for increasing power reserve of the mechanical watch

Info

Publication number: WO2017006348A1
Application number: PCT/IN2016/050214
Authority: WO
Inventors: Shreyas RAO
Original assignee: Rao Shreyas
Priority date: 2015-07-08
Filing date: 2016-06-30
Publication date: 2017-01-12

Abstract

Disclosed herein is a novel way to wind the mainspring in a mechanical watch. More specifically, the invention relates to a novel mechanism which continuously winds the mainspring of the watch even as it unwinds, thereby increasing "power reserve" of the watch. It is similar to the winding of an automatic watch with oscillating weight (that is driven by wearer movement or physical watch motion) but the mechanism of the invention does not depend upon wearer movement or physical watch motion for actuating the continuous winding of the mechanism.

Description

"A MECHANISM FOR INCREASING POWER RESERVE OF THE

MECHANICAL WATCH"

Field of Invention:

The present invention relates to a mechanism for increasing power reserve of a mechanical watch. More particularly the invention relates to a mechanism which continuously winds the mainspring as it unwinds, thereby increasing the power reserve of the watch.

Background of Invention:

A mechanical watch is a machine or system which uses a wound spring as a power source.

The mechanical watch is driven by a spring, called a mainspring, which must be wound periodically. The potential energy of the wound spring is transmitted through a series of gears to power the balance wheel that oscillates back and forth at a constant rate. The mechanism further comprises of an escapement, which allows the gears of the watch to move forward a small amount with each swing of the balance wheel, moving the watch hands forward at a constant rate. These kind of mechanical watches have been around since 1500s. Automatic self-winding watches made their appearance in the 1700's. A manually-wound watch must be wound with the pendant or a levered setting, an Automatic watch does not need to be wound by the pendant or crown although it can be wound simply rotating or moving the watch winds it automatically.

The self-winding or automatic winding mechanism is a mechanism wherein the mainspring is wound automatically as a result of natural motion of the wearer's arm, to provide energy to run the watch, making manual winding unnecessary. The earliest reference of automatic winding mechanism could be found in an article published around the end of 1773.

The automatic winding watches known till date used various kinds of mechanisms such as wig-wag mechanism (US2707371) or click and spring system (US2603941) or pivoted winding weight (US2620620) to actuate automatic winding. Most favoured mechanism used for automatic winding has been an oscillating weight. The oscillating weight is an eccentric weight which turns on a pivot. This oscillating weight may also be called as rotor. The normal movement of the arm of the wearer causes the rotor to pivot on a staff attached to a ratcheted winding mechanism. The motion of the arm of wearer is, thereby, translated into circular motion of the rotor, which through a series of reverser and reducing gears, eventually winds the mainspring. However, all mechanical watches whether automatic or manual wind would stop at some stage. Automatics would stop if not worn and manual winds would come to a stop if not wound periodically. The power reserve of a watch then assumes great significance where it is necessary to reduce the number of times the wearer has to wind the watch especially in case of complications like calendar watches which would have to be reset by a watchmaker if the watch wound down for instance. Therefore, the inventor proposes a novel mechanism of continuous winding to increase the power reserve of the watch so that it continues to function for longer periods even if it is not worn and is in one place. Moreover the inventor does away with manual winding of the crown with a simple press or actuation which initiates continuous and complete winding of the mainspring with no further intervention required by the wearer as compared to any mechanism available in the prior art.

Another mechanism available in the art for actuating winding of the clock spring was utilized by Ulysse Nardin in "Freak" watches. Ulysse Nardin watches are well known in the watch-world. The "Freak" uses the watch bezel to set the minute and hour hand, that is, as the wearer rotates the bezel, the hour hand moves. The caseback is used to wind the watch. However, the caseback does not initiate any mechanism that proceeds to wind the watch continuously and to completion.

The present invention, further, tries to change the fundamental way in which the mechanical watch is wound and also through an inventive arrangement attempts to increase the "power reserve", that is, the time taken by the mainspring to unwind completely, thereby increasing the life of the watch.

Summary of Invention:

In main aspect the invention provides a mechanism for increasing the power reserve of a mechanical watch.

Accordingly, in an aspect the invention provides a mechanism which continuously winds the mainspring as it unwinds, thereby increasing the power reserve of the watch. This can be achieved by the mainspring housed in a single barrel or it could entail the unwinding mainspring, wind itself around a second arbour in a second barrel. This means that as it unwinds in the first barrel (around the first arbour); it starts simultaneously winding around a second arbour in the second barrel. When the mainspring is fully wound in the second barrel, it starts unwinding. This means that it starts winding into the first barrel around the first arbour. Through this back and forth movement, the watch continues to function. The winding of the spring into the second barrel is controlled by the secondary balance wheel arrangement. The unwinding of the spring in the second barrel to drive watch functions however can be controlled by the first or primary balance wheel arrangement. Likewise the winding of the spring into the first barrel is controlled by the secondary balance wheel arrangement. Gear trains can be adjusted to achieve perfect sync.

In an aspect, the invention provides a mechanism for increasing power reserve of a mechanical watch which is independent of the physical movement of the wearer. In one aspect, the mechanism of the invention contains at least two balance wheels regulating at least two escapements which in turn drive two gear trains which power watch functions.

In an alternative aspect, the invention provides a mechanism containing an auxiliary spring which is wound by an auxiliary gear train. Said auxiliary gear train is powered by the unwinding mainspring.

In another aspect the invention provides a mechanical watch comprising the mechanism of the invention.

Brief Description of Drawings:

Fig. 1 illustrates a schematic representation detailing the mechanism of the invention.

Fig. 2A illustrates a crown actuator which could be used to actuate winding process.

Fig. 2B illustrates one possible rocker actuator for actuating winding process. Fig. 2C illustrates another possible rocker actuator for actuating winding process. Fig. 2D illustrates a drill type actuator for actuating winding process. Fig. 2E illustrates a slider type actuator for actuating winding process. Fig. 2F illustrates a Bezel type actuator for actuating winding process. Detailed Description of Drawings:

Fig. 1 illustrates a mechanical watch comprising the mechanism 10 of the invention in accordance with one of the embodiments of the invention. Accordingly, the mechanism comprises a primary balance wheel 1 that regulates a primary escapement(not shown) which in turn allows a primary gear train to move by a set amount (not shown). An arrangement comprising of the primary balance wheel, the primary escapement and the primary gear train could collectively be called as a primary arrangement. The primary arrangement mainly drives the regular watch functions like day, date, time etc. This primary arrangement is powered by the unwinding of mainspring contained in the barrel attached to ratchet 3. The mechanical watch further comprises a secondary balance wheel 2 that regulates a secondary escapement (not shown) which in turn allows a secondary gear train to move by a set amount (not shown). This arrangement comprising the secondary balance wheel, the secondary escapement and the secondary gear train could together be called as secondary arrangement. The secondary arrangement is exclusively used for re-winding the mainspring as it unwinds.

In an alternative embodiment the mechanism of invention further comprises an auxiliary spring barrel 5. Said barrel 5 contains an auxiliary spring which is wound by the mainspring enclosed in barrel attached to ratchet 3. Said auxiliary spring is wound simultaneously as the mainspring unwinds while performing regular watch functions. The winding of auxiliary spring barrel 5 is driven by an auxiliary gear train (not shown).

The said primary gear train or secondary gear trains or the auxiliary gear trains could be selected from Simple gear train, Compound gear train, Reverted gear train or Epicyclic gear train and all possible combinations of these to suit the application including custom gear train sets. Similarly, the gears used in the primary gear train or secondary gear trains or the auxiliary gear trains or any other gears used in the mechanism of the invention could be selected from spur gears, rack and pinion gears, ring gears, helical gears, face gears, worm gears, hypoid gears, bevel gears or screw gears and all possible combinations of these to suit the application including custom gear sets.

Description of Invention:

Described herein is a novel mechanism for increasing the power reserve of a mechanical watch.

For the purpose of this invention, unless the context otherwise requires, the terms "power reserve" or "life of the watch" or "life" convey the time taken by the mainspring to unwind completely. Power reserve of an automatic watch is very important. Conventionally, most mechanical watches have a power reserve of around 45 hrs. Some special calibres have 72 hrs and some double barrel movements can have 8 days of power reserve.

For the purpose of this invention, the term "single press", unless the context otherwise requires, means any kind of initiation or actuation after which the winding process commences on its own and stops once the winding is complete and does not require further pressing or actuating to keep the winding process active. This is also called as CommandPress or CommandCrown or CommandWind or MasterWind or MasterPress.

For the purpose of this invention, the term "reserve energy spring" or reserve amount is part of the mainspring i.e. it is derived from the mainspring itself. If e.g. 70% of mainspring is used for normal watch functions then remaining 30% of the mainspring itself is called the reserve energy spring or reserve amount. This is distinct from the auxiliary spring which is a separate spring and independent of the mainspring. For the purpose of this invention few terms are explained where the same word or word combinations could mean different things according to the context.

For the purpose of this invention, term "Continuous winding" may mean

A. ) The secondary arrangement winds continuously during normal watch operations.

B. ) The CommandPress using either the reserve amount OR auxiliary spring also winds continuously.

However both A and B are distinct.

The mechanism of the invention winds the mainspring of the watch continuously even as the mainspring unwinds. This continuous winding and unwinding can take place in a single barrel around the arbour or it could take place with the help of a second barrel and arbour. This causes it to increase the power reserve. The power reserve of the mechanical watch is increased by winding the mainspring a little, every time the mainspring unwinds a little. This continuous tendency to unwind and wind incrementally during normal watch operation increases the power reserve of the watch, thereby extending the life of the watch.

Theoretically, the mechanism of the invention should keep the watch running forever but energy loss ensures that the watch eventually comes to a stop. However, the watch comes to a stop after a comparatively extended life. The life of the watch depends upon materials used, calculations made and comprehensive testing done to keep improving the power reserve.

The invention, accordingly, provides a mechanism that is novel and unique which would help in no uncertain measure to increase the power reserve of the mechanical watch thereby extending the life of the watch. Few embodiments will now be discussed, while referring to the appended diagrams, to make the invention clear. In one of the embodiments, the mainspring is designed in such a way that the mainspring stops unwinding after a partial state of unwind. The remaining unwound portion of the mainspring is called as a reserve energy spring. For example, the mainspring is designed to stop after 70% unwinding, in which case remaining 30% is kept as reserve for the continuous winding. The reserve 30% energy of the main spring is than used to drive the shaft connected to the ratcheted winding mechanism through a distinct gear train. The reserve energy unleashed from the still wound mainspring completely winds the balance unwound portion.

For the rewinding of the mainspring, each actuation (press, slide, rotation etc.) of an actuator winds the mainspring incrementally using the reserve energy spring. Alternatively, when the actuator is kept pressed in its limiting position, the actuator initiates continuous winding of the mainspring through the reserve energy spring, derived from mainspring.

In accordance with the above embodiment, the mechanism of the invention comprises a primary balance wheel 1 and a primary escapement which allows a primary gear train to advance by a set amount to drive watch functions, and a secondary balance wheel and a secondary escapement 2 which allows a secondary gear train to advance by a set amount to drive the winding mechanism for winding of the mainspring. Accordingly, the secondary balance wheel 2 starts regulating the secondary gear train to wind the unwound 30% and then proceeds to wind the rest of the spring.

In further embodiment, the speed/frequency of the secondary gear train, that is, the rate at which it rotates the shaft connected to the ratcheted winding mechanism is adjusted so as to mimic an oscillating weight in an existing automatic movement. The speed/frequency of the secondary gear train is controlled by the secondary balance wheel/hair spring arrangement. As the mainspring unwinds and drives watch functions with the help of primary balance wheel, the secondary balance wheel regulates the secondary escapement which allows a second gear train to simultaneously start winding up the main spring.

In subsequent embodiment, the primary balance wheel 1, the primary escapement, the primary gear train, the secondary balance wheel, the secondary escapement and the secondary gear train are powered by the unwinding of the mainspring. In one of the subsequent embodiments, the primary gear train and the secondary gear train may form an integrated gear system which drives the watch functions and simultaneously winds the mainspring.

In one of the alternative embodiments, the mainspring is wound through a secondary gear train or integrated gear system without a secondary balance wheel and hair spring arrangement, that is, without any regulation mechanism and only through carefully designed gear ratios. In an alternate embodiment, since the force with which the gears are driven varies during various stages of mainspring unwind, "slipping clutches" or "slipping barrels" can be used to prevent overwind. In one of the additional embodiments, the winding of the mainspring is electronically/electrically regulated, that is, with electrical or electronic components rather than mechanical components. This means that the continuous winding can either be mechanical or electronic.

In another embodiment, the mainspring is wound by an auxiliary spring enclosed in an auxiliary barrel 5 through an auxiliary gear train. The winding of the auxiliary spring is powered by the unwinding mainspring during regular watch functions. Accordingly, the unwinding mainspring drives watch functions, winds itself through the secondary arrangement and simultaneously starts winding the auxiliary spring through the auxiliary gear system. Said auxiliary gear system can be separate or integrated. Priority in winding is given to the auxiliary spring.

Accordingly, the mainspring is allowed to wind down to 0% reserve. There exists another barrel, called as auxiliary barrel 5 with a spring, called auxiliary spring, used for exclusively winding the mainspring. When the actuator is pressed or kept pressed this auxiliary spring starts unwinding and drives the auxiliary gear train which rotates the shaft connected to the ratcheted winding system 3 thereby winding the mainspring. The auxiliary spring is independent and separate from mainspring.

Further, in accordance with above embodiment, when the mainspring unwinds, it powers a primary gear train to power watch functions like day, date, seconds etc., which is allowed to advance by a set amount by the escapement regulated by primary balance wheel. The unwinding mainspring further drives an auxiliary gear train, which in turn winds the auxiliary spring contained in auxiliary barrel 5. Finally, the unwinding mainspring also powers the secondary gear train, which is allowed to move by a set amount by the secondary escapement. The secondary escapement is in turn regulated by a secondary balance wheel 2 to wind the mainspring.

Calculations are made such that the watch comes to a stop when it is not able to generate more energy than the minimum that is required to wind the auxiliary spring. It performs this task and comes to a stop. This means that whenever the watch stops on its own, the auxiliary spring is always fully wound.

In accordance with the above embodiment, each actuation of an actuator winds the mainspring incrementally using the auxiliary spring. Alternatively, when the actuator is kept pressed, the same initiates continuous winding of the mainspring through the energy stored in the auxiliary spring or using the reserve energy derived from mainspring itself as explained earlier.

In one of the embodiments, the winding of the auxiliary spring or reserve energy spring or mainspring itself can be actuated electronically through electronic elements like micromotors and can also be computer or chip controlled. In one of the embodiments, watch front or back can be used to showcase power reserve indicators for mainspring and auxiliary spring.

In one of the embodiments, the CommandPress or CommandCrown or CommandWind or MasterWind or MasterPress may or may not be a central crown used to wind the mainspring, set watch functions like day, date, time etc. In an embodiment wherein the CommandPress or CommandCrown or CommandWind or MasterWind or MasterPress is not the central crown, the same can appear at any alternative position in the form of a crown, rocker, drill feed type mechanism, slider etc.

In an embodiment, the CommandCrown or CommandPress, or CommandWind or MasterWind or MasterPress may initiate a mechanical process with mechanical components, that is, mechanical winding or it may be an electro-mechanical process with electronic/electrical components, that is, electronic computer controlled winding or electronic motorised winding.

In another embodiment, the winding of the spring could be effected by a dynamo type system (not shown) which could wind the clock quickly in few turns. Accordingly, the dynamo type system drives a reduction gear arrangement to wind the main spring. The dynamo type system charges a battery which drives the reduction gear mechanism for a short duration till it receives a further charge from the dynamo on account of one more turn of the crown.

In further embodiment, the mechanical watch comprises a manual winding mechanism. The manual winding mechanism is actuated by any of the actuators selected from a crown (Fig. 2A), a rocker switch (Fig. 2B, 2C), a drill feed type rotary mechanism (Fig. 2D), a slot machine type lever, slider mechanism (Fig. 2E), watch bezel (Fig. 2F) or any other actuation known in the art, watch case back or any device that winds the watch through a press or rocking or rotary action and returns to original position after each press or rock or rotation. Each press or rock or rotation winds watch incrementally but the winding is continuous when held in their limiting positions.

The manner of usage and operation of the present invention should be apparent from the above description. Accordingly, no further discussion relating to the manner of usage and operation will be provided.

It is hereby clarified that the optimum dimensional relationships for the parts of the invention, to include variations in size, materials, shape, form, function and manner of operation, assembly and use, are deemed to be within the expertise of those skilled in the art. All equivalent structural variations and relationships to those illustrated in the drawings and described in the specification fall within the scope of the invention.

It is further stated that what has been described and illustrated herein are some embodiments of the invention along with some of its variations. The terms, descriptions and figures used herein are set forth by way of illustration and are not meant as limitations. Those skilled in the art will recognize that many variations are possible within the spirit and scope of the invention, which is intended to be defined by the appended claims (and their equivalents) in which all terms are meant in their broadest reasonable sense unless otherwise indicated.

Claims

A mechanism for increasing power reserve of the mechanical watch, wherein the mainspring is designed to stop after state of partial unwinding keeping a reserve amount wound for rewinding, wherein the mechanism comprises: a primary balance wheel and a primary escapement which allows a primary gear train to advance by a set amount to drive watch functions, and a secondary balance wheel and a secondary escapement which allows a secondary gear train to advance by a set amount to drive the winding mechanism for winding of the mainspring,

A mechanism for increasing power reserve of the mechanical watch, wherein the mainspring is completely unwound and an auxiliary spring is used for rewinding, wherein the mechanism comprises: a primary balance wheel and a primary escapement which allows a primary gear train to advance by a set amount to drive watch functions, and a secondary balance wheel and a secondary escapement which allows a secondary gear train to advance by a set amount to drive the winding mechanism for winding of the mainspring,

The mechanism of claim 1 and 2, wherein the primary balance wheel, the primary escapement, the primary gear train, the secondary balance wheel, the secondary escapement, the secondary gear train are powered by the unwinding of mainspring.

The mechanism of claim 1 and 2, wherein the mainspring winds and unwinds around a single arbour and in one barrel.

5. The mechanism of claim 1 and 2, wherein the mainspring while unwinding in a first barrel around a first arbour, simultaneously winds around a second arbour in a second barrel and vice versa.

6. The mechanism of claim 1 and 2, wherein the primary gear train and the secondary gear train may form an integrated gear system which drives the watch functions and simultaneously winds the mainspring.

7. The mechanism of claim 2, wherein the auxiliary spring is wound by the unwinding mainspring.

8. The mechanism of claim 2, wherein the auxiliary spring is connected to the winding mechanism, through an auxiliary gear train, which is used to wind the mainspring.

9. The mechanism of claims 1 and 2, wherein the winding of the mainspring or the auxiliary spring can be actuated electronically through electronic elements like micromotors.

10. The mechanism of claim 1 and 2 further comprises a manual winding mechanism.

11. The mechanism of claim 10, wherein the manual winding mechanism is wound by an actuator selected from a rocker switch, a crown, a drill feed type rotary mechanism, a slot machine type lever, a watch bezel, a watch caseback or any device that winds the watch through a pressing or rocking or rotary action and returns to original position after each press or rock or rotation.

12. The mechanism of claim 1 1, wherein each press or rock or rotation winds the watch mainspring incrementally.

13. The mechanism of claim 12, wherein the winding continues till the mainspring is wound completely when any of the actuators are held at their limiting position.

14. The mechanism of claim 1 and 2, wherein the mainspring can be wound by a CommandCrown or CommandPress or CommandWind or MasterWind or MasterPress.

15. The mechanism of claim 14, wherein the CommandCrown or CommandPress or CommandWind or MasterWind or MasterPress causes the auxiliary spring to unwind or reserve unwound spring to unwind.

16. The mechanism of claim 15, wherein the CommandCrown or CommandPress or CommandWind or MasterWind or MasterPress may initiate a mechanical process with mechanical components i.e. mechanical winding or it may be an electro-mechanical process with electronic/electrical components i.e. electronic computer controlled winding or electronic motorised winding.

17. The mechanism of Claim 14, wherein winding of the main spring is effected by use of dynamo type mechanism.

18. The mechanism of Claim 17, wherein the dynamo type mechanism substantially reduces the number of turns required to wind the mainspring.