GB2261751A

GB2261751A - Clock mechanisms

Info

Publication number: GB2261751A
Application number: GB9124628A
Authority: GB
Inventors: Alan Sidney Michael Jinks
Original assignee: Individual
Current assignee: Individual
Priority date: 1991-11-20
Filing date: 1991-11-20
Publication date: 1993-05-26
Also published as: GB9124628D0

Abstract

A spring or weight driven clock has the escapement 33 thereof controlled by a quartz driven stepping motor 38. As shown the escapement wheel 33 is controlled by a pall et 43 mounted on a lever 4 pivotted at 40. The other end of the lever has a slot 42 surrounding an eccentric pin 39 on stepping motor 38. The clock may be a timing device for pigeon racing. <IMAGE>

Description

Title: Clock Mechanisms Description of Invention This invention relates to clocks. Particularly, the invention relates to clocks which include a mechanically driven, e.g. spring driven, mechanism, and to a means of improving the accuracy of time-keeping of such clocks.

The invention has been devised in relation to clocks whose purpose is that of timing the arrival of racing pigeons at their home loft. Such clocks, which will herein for convenience be referred to as pigeon clocks, incorporate a mechanism which receives a ring removed from the leg of a returning pigeon and records on a chart the time at which such ring has been placed in the ring-receiving mechanism of the clock. Since the result of a race may depend on a difference in time of seconds only between the arrival times of different pigeons, the time-keeping mechanism of a pigeon clock requires relatively high accuracy.

There are many thousands of pigeon clocks at present in use of considerable age, incorporating spring-driven time-keeping mechanisms. The older ones of such clocks have difficulty in meeting the accuracy requirements established by the association which controls the sport of racing pigeon flying in this country, namely a deviation of less than 30 seconds per day from correct time-keeping. Since pigeon clocks are complex and hence expensive devices, however, there is an unwillingness for owners to discard such old clocks and buy new ones.

The present invention thus seeks to provide a means of improving the accuracy of time-keeping of clocks such as old pigeon clocks, to enable current requirements for accuracy to be met.

According to one aspect of the present invention, I provide a clock mechanism comprising mechanical driving means and electronically-controlled regulating means for determining the speed of the mechanism.

Thus, in a clock mechanism according to the present invention, a mechanically driven (preferably spring driven but possibly, alternatively, weight driven) mechanism has its speed controlled by an electronically controlled regulating mechanism instead of by the usual mechanical escapement. It is the mechanical escapement which is the principle source of inaccuracy in old clocks, and the use of an electronically controlled regulating means reduces the inaccuracies.

Preferably the regulating means includes a gear meshing with a gear in the mechanically driven mechanism, and electronically-controlled means for controlling the rotation of such gear.

Preferably the means for controlling rotation of said gear of the regulating means comprises an escape wheel rotationally connected to said gear, and a lever pivotally mounted so that stop members provided on the lever are engageable with teeth on the escape wheel, to permit stepwise rotation of the escape wheel upon oscillation of the lever, the oscillation of the lever being caused by electronic means.

The electronic means may comprise a stepping motor driven by a frequency-controlled electronic circuit so as to rotate stepwise at a constant rate, the stepping motor having an output member connected to said lever to cause said oscillation thereof. The output member of the stepping motor may comprise a pin extending substantially parallel to but offset from an output shaft of the stepping motor, such pin engaging in a slot in the lever.

The combination of a frequency-controlled circuit and a stepping motor driven thereby is very widely used as the basis for the so-called "quartz clock" of analogue type. Such clocks incorporate an extremely simple gear train to convert the movement of the stepping motor, e.g. at half a revolution per second, to that of the time-indicating hands of the clock. Thus the present invention can make use of part of a "quartz clock" movement which is commercially readily available, and use it as the regulating means in a mechanically-driven clock to achieve a much higher standard of accuracy of time-keeping than is possible with a mechanical escapement as provided in some older types of clock.

As above referred to, the invention has been devised in relation to a clock for timing the arrival of racing pigeons at their home loft. In a pigeon clock, the mechanical output of the clock usually drives a replaceable paper chart or charts (e.g. in the form of two discs, one for recording the hours and the other for the minutes and seconds) upon which a marking mechanism makes a mark to indicate the time at which a ring removed from a returning pigeon is inserted into the clock. Such marking may be made by a pointed element to punch a hole in the discs to indicate the time in hours and minutes of insertion of the ring into the clock. One of the requirements for a pigeon-timing clock is the ability to set the position of the discs relative to the clock mechanism, as otherwise a correction needs to be applied to eliminate any error arising from this source.Such setting of the clock is usually done by an official of a club to which the pigeon enthusiast belongs, such official inserting the recording discs into the clock, setting them, and then closing and locking a casing of the clock to prevent interference. Such setting is considerably facilitated if there is provided means for stopping and starting the clock mechanism, which means is not generally provided in a wholly mechanical clock.

Preferably, therefore, a clock mechanism according to the invention further comprises switch means for the electronic regulating means.

According to another of aspect of the invention, I provide a clock, which may be a pigeon clock, including a mechanism according to the first aspect of the invention as above set forth.

Preferably such a pigeon clock includes an openable casing, and when there is provided switch means for the electronic regulating means such switch means is preferably arranged to be operated to start the clock mechanism upon an initial operation of the ring-receiving mechanism of the clock.

According to a third aspect of the invention, I provide a regulating means for fitting to a mechanically-driven clock mechanism as a replacement for a mechanical escapement, comprising a gear adapted to mesh with a gear in the mechanically-driven mechanism, and electronically-controlled means for controlling the rotation of the gear of the regulating means.

The electronic means for causing oscillation of the lever may comprise a stepping motor driven by a frequency controlled electronic circuit so as to rotate stepwise at a constant speed, the stepping motor having an output member connected to said lever to cause said oscillation thereof. The stepping motor may comprise an output shaft and an output member in the form of a pin offset from said output shaft, such pin engaging a slot in the lever.

According to a fourth aspect of the invention, I provide a method of converting a clock mechanism comprising mechanical driving means and a mechanical escapement, said method comprising removing the mechanical escapement therefrom and fitting a regulating means according to the third aspect of the invention.

The invention will now be described by way of example with reference to the accompanying drawings of which: Figure 1 is a simplified diagrammatic perspective view of a clock mechanism according to the invention; Figure 2 is a perspective view, partially broken away, of part of the regulating means, according to the invention, of the clock mechanism.

Referring firstly to Figure 1 of the drawings, the mechanism there illustrated is part of the chart-driving mechanism of one type of pigeon clock, which has been modified in accordance with the invention. It will be appreciated that the complete pigeon clock further includes a casing in which the illustrated mechanism is disposed, means for receiving a number of rings which have been carried by returning pigeons, and means for marking the charts which are driven by the mechanism. Such parts of the clock, however, form no part of the present invention and remain unaltered.

The illustrated mechanism comprises two main frame plates 10, 11, which provide support for a number of shafts rotatable about axes parallel to one another and perpendicular to the plates. The first of these shafts carries a drum 12 in which a main driving spring is disposed, and has a squared end 13 for engagement by a winding key and carries a ratchet wheel 14 engaged by a pawl 15 to prevent reverse rotation of the shaft. The drum 12 carries gear teeth 16.

A main shaft 17 provided with a gear 18 is driven from the drum 16 by way of a double step-up gear 19 provided on shaft 20. Above the plate 10, the shaft 17 is provided with a square collar 21 for receiving a means for holding a first chart in the form of a paper disc, whilst beneath the collar 21 a circular member 22 is provided for supporting a second chart also in the form of a paper disc. The second paper disc would be clamped to the member 22 by a clamping element, not shown, and a screw-threaded member, also not shown, engaging threaded portion 23 above the member 22. The member 22 is rotatable on the shaft 21 and is arranged to be driven from the shaft 21 by reduction gearing indicated generally at 24, so that the disc carried on the member 22 makes one revolution for every twenty-four revolutions of the collar 21.A face plate 25 spaced above the frame plate 10 is provided with means, not shown, for supporting the paper discs to enable them to be punctured by a marking element when required.

For regulating the speed of operation of the chart driving mechanism, a gear 26 on the shaft 17 drives, by way of step-up gearing 27 on a further shaft 28, a shaft 29 which is provided with a contrate gear 30. The contrate gear 30 meshes with a gear 31 of a regulating means as described hereafter with reference to Figure 2 of the drawings. In the original design of the clock mechanism, the regulating means would have comprised a mechanical escapement with the usual components, namely an escape wheel, pivoted lever engaging teeth on the escape wheel, and a balance wheel and hair spring.

The regulating means according to the present invention is based on a "quartz clock" movement of a type which is readily commercially available.

Such a movement comprises an electronic circuit whose frequency of oscillation is precisely controlled by a quartz crystal and whose output, suitably processed, drives a stepping motor at a controlled rate of e.g. half a revolution per second.

In the complete clock, the output of such a stepping motor is applied through a simple gear train to the time-indicating hands of the clock. The present invention makes use of the circuit and stepping motor of such a clock as the regulating means for controlling the speed of the spring-driven mechanism of the pigeon clock.

In the drawings, there is shown a support member in the form of a plate 32 extending between the frame plates 10, 11 of the clock. This supports, by bearings not illustrated, the gear 31 which is disposed on the same shaft and is rotationally fast with an escape wheel 33 having teeth 34.

Spaced from the support member 32 there is a member 35 which is part of a commercially available "quartz clock" movement as above referred to, modified as necessary to enable it to be mounted on the support member 32.

This carries the frequency controlled electronic circuit of the "quartz clock" (which will not be described in detail, but which includes a quartz crystal, integrated circuit, and the necessary connections therebetween). It also supports a stepping motor with a coil 36, pole structure 37, and arbor 38 which is a permanent magnet and is rotatable stepwise within the pole structure at a speed of half a revolution per second. A pin 39 is fitted to the arbor 38, parallel to but offset from its axis of rotation.

Between the support members 32, 35 there is supported, for pivotal movement about an axis 40, and by bearings not shown, a lever 41. At its end remote from its pivotal axis 40, the lever 41 is provided with a slot 42 within which the pin 39 engages. The lever 41 is also provided with a pair of stop members 43 which are constituted by the ends of a length of wire 44 secured to the arm, the stop members extending through apertures in the support member 32 into the region of the teeth 34 of the escape wheel 33. The relationship between the stop members 43 and the teeth of the escape wheel is such that when the lever 41 is caused to oscillate about the axis 40, the stop members 43 move alternately into the path of the teeth of the escape wheel and permit the latter to rotate stepwise.

It will be appreciated that the engagement of the pin 39 fitted to the arbor 38 of the stepping motor in the slot 42 of the lever causes the lever 41 to oscillate about its axis and thus permit the above described stepwise rotation of the escape wheel 33 and hence of the gear 31. Since the arbor of the stepping motor rotates at half a revolution per second, this allows the escape wheel to move stepwise at one tooth per second, accurately to regulate the speed of operation of the spring-driven mechanism of the clock.

The stepping motor and its frequency-controlled driving circuit are typically battery powered, and a battery for this purpose may be arranged to be mounted as indicated at 45 in the face plate 25 of the clock. Suitable wiring, not shown, would of course be provided to connect to the electronic circuit which drive the stepping motor. Preferably, also, switch means is provided in such wiring which, in the case of a pigeon clock, is arranged to be operated to start the clock mechanism when, after new timing charts have been inserted, the case of the clock has been closed and the ring-receiving mechanism of the clock is operated for a first time by the clock-setting official. Clock setting is thus considerably facilitated, compared with setting a mechanically driven clock mechanism which is continuously running and has no means for stopping and starting it.

Although described above in relation to a pigeon clock, it will be appreciated that the principle of the invention, namely that of applying an electronically controlled regulating means to a mechanically driven clock mechanism, can be applied to clocks for other purposes. It will also be appreciated, that when the invention is being applied to clocks of different design, a different mechanical layout of the components of the regulating means may be adopted.

The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

Claims

1 According to one aspect of the present invention, I provide a clock mechanism comprising mechanical driving means and electronically-controlled regulating means for determining the speed of the mechanism. Thus, in a clock mechanism according to the present invention, a mechanically driven (preferably spring driven but possibly, alternatively, weight driven) mechanism has its speed controlled by an electronically controlled regulating mechanism instead of by the usual mechanical escapement. Itis the mechanical escapement which is the principle source of inaccuracy in old clocks, and the use of an electronically controlled regulating means reduces the inaccuracies.

2 Preferably the regulating means includes a gear meshing with a gear in the mechanically driven mechanism, and electronically-controlled means for controlling the rotation of such gear.

3 Preferably the means for controlling rotation of said gear of the regulating means comprises an escape wheel rotationally connected to said gear, and a lever pivotally mounted so that stop members provided on the lever are engageable with teeth on the escape wheel, to permit stepwise rotation of the escape wheel upon oscillation of the lever, the oscillation of the lever being caused by electronic means.

4 The electronic means may comprise a stepping motor driven by a frequency-controlled electronic circuit so as to rotate stepwise at a constant rate, the stepping motor having an output member connected to said lever to cause said oscillation thereof. The output member of the stepping motor may comprise a pin extending substantially parallel to but offset from an output shaft of the stepping motor, such pin engaging in a slot in the lever.

5 The combination of a frequency-controlled circuit and a stepping motor driven thereby is very widely used as the basis for the so-called "quartz clock" of analogue type.

Such clocks incorporate an extremely simple gear train to convert the movement of the stepping motor, e.g. at half a revolution per second, to that of the time-indicating hands of the clock. Thus the present invention can make use of part of a quartz clock movement which is commercially readily available, and use it as the regulating means in a mechanically-driven clock to achieve a much higher standard of accuracy of time-keeping than is possible with a mechanical escapement as provided in some older types of clock.

6 As above referred to, the invention has been devised in relation to a clock for timing the arrival of racing pigeons at their home loft. In a pigeon clock, the mechanical output of the clock usually drives a replaceable paper chart or charts (e.g. in the form of two discs, one for recording the hours and the other for the minutes and seconds) upon which a marking mechanism makes a mark to indicate the time at which a ring removed from a returning pigeon is inserted into the clock. Such marking may be made by a pointed element to punch a hole in the discs to indicate the time in hours and minutes of insertion of the ring into the clock. One of the requirements for a pigeontiming clock is the ability to set the position of the discs relative to the clock mechanism, as otherwise a correction needs to be applied to eliminate any error arising from this source.Such setting of the clock is usually done by an official of a club to which the pigeon enthusiast belongs, Such official inserting the recording discs into the clock, setting them, and then closing and locking a casing of the clock to prevent interference. Such setting is considerably facilitated if there is provided means for stopping and starting the clock mechanism, which means is not generally provided in a wholly mechanical clock.

7 Preferably, therefore, a clock mechanism according to the invention further comprises switch means for the electronic regulating means.

8 According to another of aspect of the invention, I provide a clock, which may be a pigeon clock, including a mechanism according to the first aspect of the invention as above set forth.

9 Preferably such a pigeon clock includes an openable casing, and when there is provided switch means for the electronic regulating means such switch means is preferably arranged to be operated to start the clock mechanism upon an initial operation of the ring-receiving mechanism of the clock.

10 According to a third aspect of the invention, I provide a regulating means for fitting to a mechanicallydriven clock mechanism as a replacement for a mechanical escapement, comprising a gear adapted to mesh with a gear in the mechanically-driven mechanism, and electronicallycontrolled means for controlling the rotation of the gear of the regulating means.

11 Preferably the means for controlling rotation of said gear of the regulating means comprises an escape wheel rotationally connected to said gear, and a lever pivotally mounted so that stop members provided on the lever are engageable with teeth on the escape wheel, to permit stepwise rotation of the escape wheel upon oscillation of the lever, the oscillation of the lever being caused by electronic means.

12 The electronic means for causing oscillation of the lever may comprise a stepping motor driven by a frequency controlled electronic circuit so as to rotate stepwise at a constant speed, the stepping motor having an output member connected to said lever to cause said oscillation thereof. The stepping motor may comprise an output shaft and an output member in the form of a pin offset from said output shaft, such pin engaging a slot in the lever.

13 According to a fourth aspect of the invention, I provide a method of converting a clock mechanism comprising mechanical driving means and a mechanical escapement, said method comprising removing the mechanical escapement therefrom and fitting a regulating means according to the third aspect of the invention.