GB2234369A - Rotatable reference watchglass watch - Google Patents

Abstract

A rotatable reference watchglass watch comprising. (a) a base member 1 and a mechanism bridge 2 fixed together with a train wheel mechanism located therebetween; (b) an extended pant 2a extending above the base member and mechanism bridge and having a first engagement member; (c) a reference ring 7 having a second engagement member which cooperates with the first engagement member to hold together the extended part and the reference ring whilst permitting relative rotation of the extended part and the reference ring; (d) a watchglass 8 mounted on the reference ring: (e) a dial 4 located on the mechanism bridge: (f) a rotatable reference plate 5 located above the dial and drivingly connected to a reference shaft 10 which extends through the dial and the mechanism bridge: (g) an index ring 6 arranged to rotate together with the reference plate and reference ring 7; and (h) rotation resistance means 6a, 9 acting between (i) the reference ring or index ring and (ii) the extended part or the mechanism bridge to cyclically vary the resistance to rotation of the reference ring a plurality of times during each revolution of the reference ring. The mechanism may be incorporated in a parent instrument such as an electronic pocket book. <IMAGE>

Description

ROTATABLE REFERENCE WATCHGLASS WATCH The present invention relates to the construction of a watch on which reference times can be established by manually rotating a reference ring of the watchglass.

Construcctions by which reference times are established by manual revolution of the watchglass are utilized widely in alarm watches and timers, since operations thereof are easy and quick. An example of a conventional construction for this purpose is disclosed in Japanese Utility Model Kokai No. 146,982/1987. In this construction, a base plate made of resin is installed in front of a movement and rotational movement is transmitted through a circular watch glass and reference connector (equivalent to the reference plate of this invention, referred to later) to a reference shaft penetrating and projecting into the front face of the base plate. The circular watchglass is supported at its outer periphery so as to be rotatable by a plurality of elastic hooks which project up frorn the base plate.

The conventional technology mentioned above has the following disadvantages: (1) When rotating the watchglass, it is preferable that an appropriate clicking force serves to split the reference time up into units of minutes and to prevent positional offset. However, in the conventional example, such a mechanism is not used. Even though a clicking mechanism may be provided in the interior of the movement, generally the clicking force or frictional force is too weak to obtain sufficient response due to its small mechanism size, and also its ability to prevent accidental rotation of the watchglass is insufficient.

(2) Owing to the presence of an elastic hook outside the watchglass reference ring and also to the presence of an outer case on its outside, a thick rim is formed on the outside of the display face (dial face) so that the external shape of watch is large in size, both absolutely and relatively compared to the display face, and this detracts from its appearance and commercial performance.

(3) Owing to the construction mentioned above, it is not always easy to arrange the watchglass reference ring on the outermost side of the external part of the watch.

(4) It lacks any ability to stop an alarm operation.

According to the present invention, there is provided a rotatable reference watchglass watch, comprising: (a) a base member and a mechanism bridge fixed together with a train wheel mechanism located therebetween; (b) an extended part extending above the base member and mechanism bridge and having a first engagement member; (c) a reference ring having a second engagement member which cooperates with the first engagement member to hold together the extended part and the reference ring whilst permitting relative rotation of the extended part and the reference ring; (d) a watchglass mounted on the reference ring; (e) a dial located on the mechanism bridge; (f) a rotatable reference plate located above the dial and drivingly connected to a reference shaft which extends through the dial and the mechanism bridge;; (g) an index ring arranged to rotate together with the reference plate and reference ring; and (h) rotation resistance means acting between (i) the reference ring or index ring and (ii) the extended part or the mechanism bridge to cyclically vary the resistance to rotation of the reference ring a plurality of times during each revolution of the reference ring.

Preferably, the watch further comprises an operating lever engaged with an alarm control switch operating lever and a guide mechanism arranged to allow an upper end part of the operating lever to slide approximately parallel to the outer periphery of the reference ring.

The following are the benefits of embodiments constructed in accordance with the present invention: (1) a simple construction, and a reliable sense of click can be obtained as the reference ring is rotated.

(2) almost no components are furnished in and outside the reference ring, so that a frame may be made narrower against the dial and a product of better appearance can be obtained.

(3) a watch which is capable of accomplishing both the alarmstop operation and reference time setting from the front face.

(4) a watch which may be assembled into another instrument, such as an accessory watch.

The invention will now be described by way of non-limiting embodiments with reference to the accompanying drawings, in which: Fig. 1 is a cross-sectional view of a first embodiment of a watch according to the present invention, Fig. 2 is an exploded perspective view of the first embodiment, and Fig. 3 is an exploded perspective view of a second embodiment of a watch according to the present invention.

Referring to the first embodiment shown in Figs. 1 and 2, a base plate 1 is made of synthetic resin and is formed to an approximately cylindrical shape with a closed bottom. In an interior mechanism space ic, even though not illustrated, there is a movement which consists of elements such as a train wheel, a motor, a quartz watch circuit, an electric power source, a reference mechanism (a switching mechanism capable of setting the alarm time for the alarm watch or the timer), a buzzer and contact points of an alarm-stop switch (for switching on/off the alarm function).

A back plate la of the base plate 1 has a bearing hole (not illustrated) for the lower pivot of the train wheel and performs the main plate function. In addition, it also serves both as a movement case together with a cylindrical side-face plate ib of the base plate 1. A mechanism bridge 2 has an approximately circular disc shape and covers the upper part of the mechanism space ic. The mechanism bridge 2 has a bearing hole (not illustrated) for the upper pivot of the train wheel and is fixed on a plurality of supports id with set screws 3, so as to maintain a prescribed distance between the mechanism bridge 2 and the back plate la. The mechanism bridge 2 also serves as the front plate of the movement casing.A reference shaft 10 and shafts 11 for hands (hour hand shaft, minute hand shaft and second hand shaft) project from its centre hole. The mechanism bridge 2 also supports a dial 4 which is adhered closely to its upper surface. The dial 4 is accurately located by engaging a concave part 4a with a convex part 2a of the mechanism bridge 2. The dial 4 has a printed time scale 4b.

On the upper face of the mechanism bridge 2, there is formed a ring-shaped reference plate seat 2b and a reference plate 5 is mounted thereupon. A non-circular hole Sc at the centre of the reference plate 5, which is made of transparent resin plate, fits on a non-circular portion of the reference shaft 10, so that rotation may be transmitted from the reference plate 5 to the reference shaft 10. A reference mark 5b which serves as an indicator for indicating an alarm set time is printed on the reference plate 5.

An index ring 6 is rotatable, being guided by the reference plate seat 2b, and has on its outside index teeth 6a. In addition, on its inside a convex part 6b engages a concave part 5a of the reference plate 5 so as to transmit rotation thereto. A convex part 6c of the index ring 6 engages a convex part 7b of a reference ring 7 which is manually rotatable. The outer diameter of the reference ring 7 (the diameter of which is suitable to be gripped by fingers to effect the manual rotation operation and has a diameter of for example about 3 to 10 cm) is larger than the outer diameter of the base plate 1.

A watchglass 8 is integral with the reference ring 7, and the spacing between the watchglass 8 and the reference plate 5 forms a pointer space in which are located the hour hand 12, minute hand 13 and second hand 14, all attached to the shafts 11.

The side face plate ib of the base plate 1 has an extended part 18 which extends above the mechanism bridge 2 and has a plurality of lugs le which cooperate with a flange 7a on the periphery of the reference ring 7 to restrain axial movement of the reference ring 7 whilst permitting the reference ring 7 to rotate.

A shallow concave recess lf is provided on the inner face of the side-face plate 1b and contains an index spring 9 which has a central projecting part which imparts the clicking effect when the index ring 6 revolves, by virtue of the fact that the central projecting part of the index spring 9 engages the index teeth 6a of the index ring 6.

The movement, as mentioned above, has contact points for an alarm stop switch. An alarm ON/OFF switch 15 is slideable along the outer surface of the base plate 1. A lower end part 16a of an operation lever 16 is engaged with the switch 15, and an upper end part 16b extends up to the same level as the reference ring 7 and is located radially outwards of the reference ring 7. An alarm stop operation can be executed by moving the upper end part 16b, which is serrated in order to make it easy to move with a finger. The inner surface of the operation lever 16 has a concave surface conforming to the shape of the cylindrical surface of the base plate 1, so that it slides over the surface thereof.

This watch, which has the generally cylindrical base plate 1 as a movement casing and the reference ring 7 larger than the base plate 1 in terms of outer diameter, may be used by itself as a small watch, but it may also be used embedded into a parent instrument such as a box type or card type instrument or an electronic pocket-book, as an accessory watch.

In this case, the coupling with the parent instrument is achieved by utilizing a part of the base plate 1 (press fitting, hook, screw thread joint or the like), allowing the reference ring 7 and the upper end part 16b of the operation lever 16 to project slightly above the parent instrument for ease of operation from the front face.

A second embodiment is illustrated in Fig. 3. As to a cross-sectional view of the second embodiment, it has been omitted, since it can be deduced easily by referring to Fig. 1 on the basis of Fig. 3. In addition, illustrations of the dial 4, reference plate 5, hour hand 12, minute hand 13, second hand, etc. have been omitted as these are the same as for the first embodiment. As to the train wheel, it is also the same.

A main plate 21 has a shallow cup shape, and it has holes and pillars for bearings of the train wheel, a recessed part for a button type electric cell, a post with a threaded hole 21a, a positioning notch 21b, a cylindrically shaped side face part 21c, etc. A window part 21d is a notched part of the side face part 21c and a bottom face part, and forms a window through which an operating pin of an alarm stop slide switch (not illustrated) projects downwards.

A mechanism bridge 22 also has a shallow cup shape. Its bottom face has a centre hole 22a, and its not illustrated lower face, like the upper face of the above mentioned main plate 21, has a pivot hole for the train wheel and recessed parts. Posts 22d permit the mechanism bridge 22 to be screwed to the posts 21a of the main plate, to hold in place the train wheel. An upwardly extending cylindrical extended part 18 has on its inner periphery indexing teeth 22c. A stepped part 22b provides an outwardly projecting flange which retains the reference ring 27 by means of a lug 27a.

An indexing ring 26 comprises a rigid ring and a triangularly shaped indexing point 26c supported on an indexing spring 26d. A concave part 26a transmits the rotation of the reference ring 27 to the index ring 26 and a convex-part 26b transmits the rotation on to the reference plate 5. When the indexing point 26c slides over the indexing teeth 22c, the required clicking effect is achieved. The thickness of the index ring 26 is determined by the thickness of the total height of the hour hand, minute hand and second hand.

The reference ring 27 is integral with the watchglass 8.

Unlike the other parts, the reference ring 27 and watchglass 8 are shown viewed from below in Fig. 3. The outer periphery of the reference ring 27 has concavities and convexities which act as a grip surface to permit the ring 27 to be manually rotated. A groove 27b receives the index ring 26, and relative rotation of the reference ring 27 and index ring 26 is prevented by a convex part 27c and a concave part 26a. When the reference ring 27 and index ring 26 have been assembled together the reference ring 27 is placed on the mechanism bridge 22. The lugs 27a are slipped over the stepped part 22b so as to permit the reference ring 27 to rotate but not move axially.

A frame body 19 receives the assembled components. Its inner diameter clearance-fits with the outer diameters of the main plate 21 and mechanism bridge 22, and its depth is such that the reference ring 27 is positioned just above a flange part 19c. Even though it is not illustrated, the interior contains positioning projections which engage with the notches 21b in the main plate 21. 19d is an electric-cell window for replacing the electric cell of the movement from outside the frame.

"26" is the operating lever for the alarm stop switch, which has a pin engaging part 26a arranged to cooperate with an operating pin of a sliding switch (not illustrated) located beneath the window part 21d of the main plate. The lever 26 is located in a window part 19a with its wings 26b projecting into recesses 19b. The window part 19a permits the operating lever 26 to slide within a prescribed range of angles (for example, 5 to 30 degrees) along the outer periphery 21c of the movement.

The upper end part 26c, located immediately outside the reference ring 27 and having a concave/convex finger grip, slides on the top face of a flange part 19c around the outer periphery of the reference ring 27 to switch on and off the alarm. The frame body 19 may constitute an intermediate component when assembling the movement, as well as guiding movement of the operating lever.

The principal parts mentioned above are generally moulded from synthetic resin.

The following are examples of possible modifications: (1) As to the shape of the base plate and extended part, these do not have to be cylindrical externally for the reference ring to be rotatable.

(2) As to the indexing teeth, they may extend axially instead of radially, such as from the top face of the mechanism ring or from the bottom face of the reference ring.

(3) The sliding direction of the operating lever does not have to be arcuate and may instead be straight.

Claims (3)

1. A rotatable reference watchglass watch, comprising: (a) a base member and a mechanism bridge fixed together with a train wheel mechanism located therebetween; (b) an extended part extending above the base member and mechanism bridge and having a first engagement member; (c) a reference ring having a second engagement member which cooperates with the first engagement member to hold together the extended part and the reference ring whilst permitting relative rotation of the extended part and the reference ring; (d) a watchglass mounted on the reference ring; (e) a dial located on the mechanism bridge; (f) a rotatable reference plate located above the dial and drivingly connected to a reference shaft which extends through the dial and the mechanism bridge; (g) an index ring arranged to rotate together with the reference plate and reference ring; and (h) rotation resistance means acting between (i) the reference ring or index ring and (ii) the extended part or the mechanism bridge to cyclically vary the resistance to rotation of the reference ring a plurality of times during each revolution of the reference ring.

2. A watch according to claim 1, further comprising an operating lever engaged with an alarm control switch operating lever and a guide mechanism arranged to allow an upper end part of the operating lever to slide approximately parallel to the outer periphery of the reference ring.

3. A rotatable reference watchglass watch substantially as herein described with reference to the accompanying drawings.