GB2290155A - Automatic winding mechanism - Google Patents

Abstract

An automatic winding mechanism for a clock includes an electric drive motor 18 for imparting drive through shafts 26, 28 to an epicyclic gear arrangement. The latter comprises a sun pinion wheel 30 Fig. 1, not shown, meshing with a planet pinion wheel 34, the latter in turn meshing internally of an outer gear ring 36 which controls an operating mechanism for the clock. The wheel 30 is rotatably mounted on a barrel 44. When the motor 18 is switched off, a weight, hanging from a wire rope which is wound around the barrel 44, unwinds the rope from the barrel 44, so that the latter is rotated and drives the gear arrangement and thereby the operating mechanism for the clock. When sufficient revolutions of the barrel 44 are monitored, the drive motor 18 is actuated and, through the gear arrangement, continues to impart drive to the clock operating mechanism, while rotating the barrel 44 to raise the weight for subsequent weight driving of the clock mechanism. <IMAGE>

Description

Clock Winding Mechanism This invention relates to a clock winding mechanism and particularly to a winding mechanism for a clock of the larger kind, usually known as a turret or tower clock.

According to the present invention there is provided a winding mechanism for a clock, the mechanism comprising an epicyclic gear arrangement operatively connectible with an operating mechanism for the clock, weight means connected with the gear arrangement whereby movement under gravity of the weight can drive the clock operating mechanism through the gear arrangement, means operatively connected with the epicyclic gear arrangement to effect movement of a switch actuator, and switch means engageable by the switch actuator after a movement thereof corresponding to a length of downward travel of the weight means, the switch being arranged to control operation of drive means whereby the latter reverses the action of the epicyclic gear arrangement to raise the weight means without interference with the drive to the clock operating mechanism.

Preferably the means for effecting movement of the switch actuator comprises a further gear arrangement operatively connected with the epicyclic gear arrangement, and the switch means may be engageable by the switch actuator after a selected movement thereof corresponding to a selected length of downward travel of the weight means.

Preferably also a winding barrel for the weight means carries a pinion on which a planet wheel of the epicyclic gear arrangement is mounted, the planet wheel meshing with a sun wheel fixed on an output shaft of the drive means, and with internal teeth on an outer ring, whereby, as the barrel is rotated by unwinding of the weight means, the barrel drives the planet wheel around the sun wheel and the planet wheel in turn rotates the outer ring in the same direction at a slower speed, the drive to the operating mechanism for the clock being derived from the outer ring.

The further gear arrangement may comprise a first gear fixed for rotation with the winding barrel and meshing with a second gear, the latter driving a worm gear which meshes with a wormwheel carrying the switch actuator. The switch is positioned relative to the wormwheel whereby to be actuated by the switch actuator after a selected amount of rotation of the wormwheel corresponding to a selected number of revolutions of the winding barrel.

A further switch actuator may be provided on the wormwheel, and a safety override switch may be so positioned relative to the wormwheel that, in the event of a failure of the switch for operating the drive means, the further switch actuator will subsequently engage the safety override switch.

The invention may also provide a clock incorporating a winding mechanism as described in any of the five preceding paragraphs.

Embodiments of the present invention will now be described by way of example only, with reference to the accompanying drawings, in which: Fig. 1 is a plan view of a first embodiment of a clock winding mechanism according to the invention; Fig. 2 is a side elevation of the mechanism of Fig. 1 in the section through the centre; Fig. 3 is a section on A-A of Fig. 2; and Fig. 4 is a section similar to Fig. 3 but relating to a second embodiment.

Referring to Figs. 1 to 3 of the drawings, an automatic winding mechanism for a clock comprises a framework having a base plate 10, a support plate 12 upstanding towards one end of the base plate 10, and a bearing plate 14 mounted on the support plate 12 and spaced therefrom on the opposite side thereof from the base plate 10 by a plurality of spacer rods 16. An electric drive motor 18 is mounted on a plate 20 which is in turn mounted on the support plate 12 in a spaced relation thereto above the base plate 10 by a plurality of spacers 22. A further mounting plate 24 as hereinafter described is supported by the motor mounting plate 20 to extend therefrom generally above the drive motor 18.

An output drive shaft 26 of the motor 18 is coupled to an extension shaft 28 which is supported in bearings 30 to extend between the support plate 12 and the bearing plate 14. The extension shaft 28 supports an epicyclic gear arrangement 30 by mounting thereon a sun pinion wheel 32 which meshes with a planet pinion wheel 34, the latter in turn meshing with internal teeth on an outer gear ring 36. The latter mounts a sprocket 38 arranged to operate a roller chain drive (not shown) to a chosen shaft of an operating mechanism for the clock. The ring 36 is supported on the extension shaft 28 through a suitable bearing 40.

The planet wheel 34 is rotatably mounted on a stud 42 which is fixed to a rotatable barrel 44, the latter being supported on the extension shaft 28 through a suitable bearing 46. A weight (not shown) hangs in a loop of a wire rope which is wound around the periphery of the barrel 44. On the side thereof opposite the stud 42, the barrel 44 is fixed for rotation with a spur gear 48, the latter meshing with a further spur gear 50 (Fig. 3). The latter has a shaft 52 extending through the support plate 12 above the level of the mounting plate 24 and has a plain worm gear 54 thereon at a location spaced from the support plate 12. The worm gear 54 is in meshing engagement with a wormwheel 56 which is mounted for rotation on a shaft 55 on the mounting plate 24 and carries a pair of upstanding switch actuators 57.A first switch assembly 58 is mounted to extend above the wormwheel 56 at a selected location, and provides a switch in circuit with the circuitry of the drive motor 18 to control operation thereof. A further switch assembly 60 is located above the wormwheel 56 in a spaced relation to the first assembly 58 and provides a safety override switch.

Until power is supplied to the drive motor 18, the sun wheel 32 does not rotate, so that, as the action of the weight unwinds the rope off the barrel 44 and the barrel 44 is thereby rotated, the planet wheel 34 carried by the barrel 44 travels around the sun wheel 32. In this travel, the planet wheel 34 meshes with the internal teeth on the outer gear ring 36 and therefore rotates the latter in the same direction but at a lower speed. The rotation of the ring 36 drives the operating mechanism for the clock. A ratchet 62 is mounted on the drive motor shaft 26 and co-acts with a pawl (not shown) to ensure the sun wheel 32 does not normally rotate.

As the planet wheel 34 travels round the sun wheel 32 under the action of the lowering weight, the rotation of the spur gear 48 with the barrel 44 rotates the further spur gear 50 and, through the shaft 52 thereof, rotates the worm gear 54. The latter rotates the wormwheel 56 and moves the switch actuators 57. The switch assembly 58 may be positioned relative to the respective actuator 57 whereby to allow sufficient revolutions of the barrel 44 as required for operation of the clock. When the actuator 57 operates the switch, the drive motor 18 is actuated and therefore begins to rotate the sun wheel 32 so that the planet wheel 34 now runs around the teeth of the outer ring 36 in the opposite direction, the barrel 44 moving with the planet wheel 34. The weight is therefore raised without interfering with the drive to the clock operating mechanism. The wormwheel 56 then rotates in the opposite direction until the actuator 57 moves out of engagement with the switch, to remove the power to the drive motor 18, thereby stopping same.

In the event of a failure of the switch assembly 58, the wormwheel 56 will continue to turn until the other switch actuator 57 operates the safety override switch. The fault in the switch assembly 58 can then be located and corrected, whereafter the safety override switch is reset manually.

There is thus provided an improved winding mechanism which can be adjusted to accommodate required revolutions of the winding barrel and correspondingly different lengths of travel for the drive weight.

Whereas the operating mechanism for the clock can be adequately rewound on a single turn of the barrel 44 when the clock is battery driven, a clock which has hour striking components and quarter hour chiming components requires a more continuous use, and a longer drop, of the weight arrangement. This improved winding mechanism is therefore particularly suitable for such clocks, and especially clocks of the larger kind, for example turret or tower clocks.

In the embodiment of Fig. 4, the switch assemblies 58, 60 are in different locations from those in the first embodiment. In the latter there is omitted the spur gear arrangement and also the wormwheel arrangement with its mounting plate 26, but otherwise the winding mechanism in the same manner as described in relation to the first embodiment.

Referring to Fig. 4, on the side opposite the stud 42, the barrel 44 is fixed for rotation with a cam plate 64 which has a switch actuating part 66 extending radially outwardly thereof. The switch operating part 66 is arranged to engage, when appropriate, with the switch for operation of the drive motor 18, an over-wind switch 68, or the safety override switch1 the assemblies of the switches being mounted on the face of the support plate 12 adjacent the barrel 44.

Various modifications may be made without departing from the invention. For example the configuration of the gear arrangements may differ from those described and shown, as may be the relative positioning of the various components in the mechanism.

Whilst endeavouring in the foregoing Specification to draw attention to those features of the invention believed to be of particular importance it should be understood that the Applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to and/or shown in the drawings whether or not particular emphasis has been placed thereon.

Claims (14)

Claims:

1. A winding mechanism for a clock, the mechanism comprising an epicyclic gear arrangement operatively connectible with a clock operating mechanism, weight means connected with the gear arrangement whereby movement under gravity of the weight can drive the clock operating mechanism through the gear arrangement, means operatively connected with the epicyclic gear arrangement to effect movement of a switch actuator, and switch means engageable by the switch actuator after a movement thereof corresponding to a length of downward travel of the weight means, the switch being arranged to control operation of drive means whereby the latter reverses the action of the epicyclic gear arrangement to raise the weight means without interference with the drive to the clock operating mechanism.

2. A mechanism according to Claim 1, wherein the mechanism comprises a winding barrel for the weight means which carries a pinion on which a planet wheel of the epicyclic gear arrangement is mounted, the planet wheel meshing with a sun wheel fixed on an output shaft of the drive means, and with internal teeth on an outer ring, whereby, as the barrel is rotated by unwinding of the weight means, the barrel drives the planet wheel around the sun wheel and the planet wheel in turn rotates the outer ring in the same direction at a slower speed, the drive to the operating mechanism for the clock being derived from the outer ring.

3. A mechanism according to Claim 1 or 2, wherein the switch means is engageable with the switch actuator after a selected movement thereof corresponding to a selected length of downward travel of the weight means.

4. A mechanism according to any of Claims 1 to 3, wherein the means for effecting movement of the switch actuator comprises a further gear arrangement operatively connected with the epicyclic gear arrangement.

5. A mechanism according to Claim 4, wherein the further gear arrangement comprises a first gear fixed for rotation with the winding barrel and meshing with a second gear, the latter driving a worm gear which meshes with a wormwheel carrying the switch actuator.

6. A mechanism according to Claim 5, wherein the switch means is positioned relative to the wormwheel whereby to be actuated by the switch actuator after a selected amount of rotation of the wormwheel corresponding to a selected number of revolutions of the winding barrel.

7. A mechanism according to Claim 5 or 6, wherein a further switch actuator is provided on the wormwheel.

8. A mechanism according to Claim 7, wherein a safety override switch is so positioned relative to the wormwheel that, in the event of a failure of the switch for operating the drive means, the further switch actuator will subsequently engage the safety override switch.

9. A mechanism according to Claim 4, wherein the further gear arrangement comprises a first gear fixed for rotation with the winding barrel and connected by a shaft to a camming plate, the latter providing a switch actuator.

10. A mechanism according to Claim 9, wherein the switch means is positioned relative to the camming plate whereby to be actuated by the switch actuator on rotation of the camming plate.

11. A mechanism according to Claim 9 or 10, wherein a safety override switch is positioned relative to the camming plate so that, in the event of a failure of the switch for operating the drive means, the switch actuator will subsequently engage the safety override switch.

12. A clock winding mechanism including a mechanism according to any of the preceding Claims.

13. A winding mechanism for a clock substantially as hereinbefore described with reference to the accompanying drawings.

14. Any novel subject matter or combination including novel subject matter disclosed, whether or not within the scope of or relating to the same invention as any of the preceding Claims.