The present invention relates to a time display device with at least one linear scale divided into at least two parallel scale sections arranged side by side and having their scale divisions plotted in opposite directions, with guiding elements running between these sections, with at least one member attached to the guiding elements and movable along the linear scale sections, with driving means moving this member, and with display means attached to this member for the display of time on the scale sections.
Linear time displays of this kind are known, for instance, from patent documents EP 0,509,965 or U.S. Pat. No. 2,221,413. The mechanisms reported there have a pointer guided along the two straight-line sections of the scale that are positioned side by side, the pointer changing its direction of motion at each end of the linear sections by a semicircular turn facing outward and being returned along the other linear scale section. The pointer thus moves along a track consisting of two semicircular ends linked by two elongated straight central sections, rather than along the customary circular track of an ordinary timepiece. It is fundamentally impossible, however, to attain a true linear display with this design, since the display is of course nonlinear in the radial track portions. Moreover, the linear track portion is perceptibly shortened relative to the radial track portion, to an extent that depends on the turning radius that must be provided toward the outside, depending on the size of the pointer, which partly offsets the aesthetically desired effect of a linear display.
A device aiming at the same aesthetic effect is known from patent application EP 1,416,339, the display in this case occurring in fact exclusively linearly. However, here the pointer simultaneously extends over both of the scale sections that are positioned side by side, and thus makes the display difficult to read unless an unambiguous indication is given which of the two sections must be read. An additional display of the direction of travel of the driving device proposed in this document merely yields a moderate improvement of legibility of the device.
It is the aim of the present invention to realize a purely linear display for a time-measuring instrument that avoids the precited disadvantages of known systems while more particularly aiming at fully exploiting the aesthetic effect of a linear display, using linear display sections exclusively, and by an appropriate technical realization of motions of the display elements at the ends of the linear scale sections not giving rise to restrictions concerning the design solutions.
Thus, object of the present invention is a time display device having the characteristics of claim 1 or claim 20.
According to claim 1, the device that is the object of the invention is characterized to that effect, more particularly by display means attached in such a way to the member that is movably attached to the guiding means that, when reaching one of the ends of a linear scale section, they will turn over to the other scale section, the turn occurring at least partially in a jumping and instantaneous manner. This is advantageous, in that on the one hand linear scale sections alone may be used so as to reinforce the aesthetic effect, and that on the other hand it is unambiguously clear from the display at any time which of the sections should be read. This will be true more particularly when the display means are attached to said member in such a way that, when attaining any of the ends of a linear scale section, they turn over to the scale section running parallel to it, in an entirely jumping and instantaneous manner, that is, the turning occurs at once in a single jump in the instant when the end of a linear section has been attained.
Further design options are opened up in such a linear display, more particularly because of the fact that the display means are attached to said member in such a way that the turning motion will occur in a direction perceptibly pointing toward the center of the time display device. This implies that the linear scale sections are not restricted in their longitudinal extent by the space requirements of a turning circle of the display means that is pointing toward the outside, as in the prior art.
The device that is object of the invention according to claim 20 attains the same precited advantages by an attachment of the display means to said member that is an alternative to that of claim 1, and that is such that upon reaching the end of a linear scale section, they turn over from one scale section to the other while the turning involves a linear motion of the display means.
Further developments of these two basic design options of the device reside in the selection of the guiding and display means, and above all of the driving means and associated layout of the member that interacts with them and is movably attached to the guiding means.
Their advantages result from the features cited in the dependent claims, and from the description setting forth the invention in detail in what follows, with the aid of drawings.
The appended drawings represent schematically and by way of example several embodiments of a linear display according to the present invention.
a and 3b represent frame and gear train of the base module of the display device in greater detail in perspective and from the front.
a, 4b and 4c are detailed views of the interplay between the mobile member, the guiding means, and the screws of the driving means.
a shows a first embodiment of the display means and their arrangement on the mobile member according to the present invention, the pointer positions being shown, both in the original place and after the turn, and for both scale ends;
a is a view of a second embodiment of the display means and of their arrangement on the mobile member according to the present invention, the pointer positions being shown at the two scale ends and at scale center;
a is a top view of a third embodiment of the display means and their arrangement on the mobile member according to the present invention, the pointer positions being shown in their original place and after the turn, and for both scale ends;
In the following the invention will be described in detail with the aid of the figures mentioned.
Referring to
A timepiece, and more particularly a wristwatch, that includes a time display device 1 according to the invention may be subdivided into structural components serving in the closer description that follows next, viz., first, an ordinary watch case including the corresponding movement, secondly, a base module forming the mechanical structure of the linear display that is cooperating with the movement, and finally, a display module movably arranged on the base module that houses the display means. The latter two modules taken together constitute a linear display according to the present invention, in the different embodiments of these modules, and will now be explained in detail.
These two modules may then be fixedly mounted on any mechanical or electronic base movement of corresponding size, parallel to said movement and in any desired angular orientation relative to the customary 6-o'clock—12-o'clock-line of a timepiece with hands, as shown in
In the embodiment sketched in
To frame 1.1, at least one linear scale 2 is attached that constitutes the dial of the timepiece, as it were, and may partially or completely cover up frame 1.1 and screws 5.2 and 5.3, respectively. Each scale 2 is subdivided into at least two parallel scale sections 2.1, 2.2 positioned side by side, as mentioned earlier, with scale divisions plotted in opposite directions, see
The guide rail 3.1 or a so-called longitudinal guidance supporting a member 4 runs between these sections, and parallel to them. The geometric shape of the rail's cross section may be selected in different ways, as will be explained in greater detail below, alternatively the rail could be constituted by the scale sections 2.1, 2.2 forming the dial, the member 4 being guided between them; further variants of this kind can be imagined. Rail 3.1 could be enabled to move to and fro within frame 1.1 between the two screws 5.2, 5.3 with the aid of grooves (not shown) or smaller guides laterally mounted or machined into frame 1.1. This option of moving guide rail(s) 3.1 would make possible an engagement or disengagement by rail movement, to be explained later. Several guide rails could be attached in series or in parallel, each supporting at least one member 4, when several scales for the display of hours and minutes for example are present.
The two screws 5.2, 5.3 are mounted parallel to each other and to guide rail 3.1 within the plane of frame 1.1, so as to be able to rotate about their axes, and have helical threads. These threads have a triangular, trapezoidal, or rectangular profile, or another profile that is specially defined, and a pitch matched to the speed and direction of rotation of the screws, similar to a classical screw thread. As shown in
The two screws 5.2, 5.3 are driven by the movement via driving gear train 5.1, and more particularly via a coupling wheel 5.1.1. In the embodiment shown in
It is an advantage of such a gear train 5.1 that it is immediately useful as drive for one or several screws 5.2, 5.3 involving corresponding rotations and directions of rotation in a variety of mechanisms, even as a basis for display functions other than those for hours and minutes, that is, a time display in the narrower sense, so for instance for time displays in timepieces such as the display of power reserve, of calendar data, of moon phases, of the duration of sunshine, or for chronographs, too. In principle, therefore, all display functions known or used thus far in timepieces may be driven without any restrictions by such a gear train 5.1 and screw-type parts 5.2, 5.3 of the kind described above.
Further, it is prior art to control the number of revolutions of the screws 5.2, 5.3 in all rotary positions in a synchronous, mutually independent, continuous or intermittent way or any combination of these options, using a mechanical calculating mechanism. Step motor technology controlled electronically would be an alternative.
In the example of
In addition, a display module realizing the display function through the force transmitted from the movement via the base module is needed in order to secure the function of the time display device 1, as had been mentioned. This display module consists of at least one member 4 attached to the guiding means 3 so as to be mobile along the linear scale sections 2.1, 2.2, and of display means 6 arranged on the member and displaying time on the scale sections.
Preferably, member 4 is formed as a sliding carriage 4.1 that can be displaced along guide rail 3.1. In the field of classical mechanical engineering, such a slide is known as a linear stage for linear or ball guidances. Slide 4.1 holds the display means 6, as can be taken from
In this example, slide 4.1 is driven by screws 5.2, 5.3 with the aid of a guide beam or crossbar 4.2 that is arranged on it and can be moved in a direction perpendicular to the screw axis. To this end, crossbar 4.2 is engaged into the grooves of the helical thread of one of the screws 5.2, 5.3. When one of the screws 5.2, 5.3 is rotated in a given direction, slide 4.1 is pushed in the pitch direction of the screw thread while crossbar 4.2 is engaged into the thread of this screw, and thus it is guided in this direction on guide rail 3.1 along the associated scale section 2.1, 2.2. At the end of rail 3.1 and of screw 5.2, 5.3 or of the scale sections 2.1, 2.2, the direction of motion of the slide 4.1 must be inverted. The change of direction comes about by a lateral shift of crossbar 4.2 from one screw 5.2, 5.3 to the other screw facing it. In the example shown, the screw thread of the other screw is opposite, for a given direction of rotation, so slide 4.1 will now be transported in the other direction by the interplay between crossbar 4.2 and this screw. This mode of functioning also serves to clearly explain the alternatives mentioned above, for the design and arrangement of driving means 5 and screws 5.2, 5.3.
By a lateral shift of crossbar 4.2, the reversal of linear motion of member 4 is realized, hence it will be explained in greater detail with the aid of
Crossbar 4.2 is inserted loosely with small play into an elongated groove of matching cross section at the surface of slide 4.1, and in its height is limited by a reversing lever 4.3 pivoted at a point of attachment 4.3.1. A control pin 4.2.1 serving to control the reversing lever 4.3 is arranged in the center of crossbar 4.2, as shown in
Positioning pins 1.2 may be arranged close to the screw ends, laterally inside of frame 1.1, as schematically shown in
Device 1 of the invention is distinguished primarily by the particular design of the display module and of display means 6, or their arrangement on member 4. For this reason, in what follows we are going to describe in detail three preferred embodiments of display means 6 and their arrangement on member 4 that had just been explained, as well as their cooperation with the base module.
The first variant consists of a display module having display means 6 that can be rotated through 180° toward the center of time display device 1, and will be explained in detail in what follows.
It can be seen from
Display means 6 further comprise the means for reversing the pointer 6.1 which cooperate with member 4 or the parts attached to member 4, as shown in detail in
A toothed control disk 6.2.1 serving to control the dial train 6.3 is arranged between reversing lever 4.3 and slide body 4.1. Together with reversing lever 4.3, disk 6.2.1 is attached via control pin 4.2.1 at the point of attachment 4.3.1 so that these parts may rotate concentrically and in synchrony. The upper edge of disk 6.2.1 has two notches cooperating with a catch 6.2.2 here shown symbolically, each notch corresponding to one of the two extreme positions of reversing lever 4.3. Catch 6.2.2 produces a form-locking positioning of reversing lever 4.3 via control disk 6.2.1 and pin 4.2.1, either in addition to or in place of the above-mentioned catch 4.4 of slide 4.1. The lower edge of disk 6.2.1 has teeth within a certain sector which, depending on the position of a clutch disk 6.3.1, will engage with a first pinion 6.3.3 or a second pinion 6.3.4 sitting on this disk. Clutch disk 6.3.1 is freely pivoted on slide 4.1 in a point of rotation 6.3.2, and is connected in a form-locking and controllable manner with crossbar 4.2 via the pincers of reversing lever 4.3 or control pin 4.2.1.
By a shift of crossbar 4.2, this disk is rotated in two phases into one of the two positions corresponding to the extreme positions of reversing lever 4.3 or of the toothed control disk 6.2.1. In a first phase, the second pinion 6.3.4 (which like the first pinion 6.3.3 is mounted idle onto the clutch disk 6.3.1) is slowly pushed into the teeth of this disk by the movement of crossbar 4.2 in the upper position of slide 4.1 that is shown. In a second phase, control disk 6.2.1 still is driven by crossbar 4.2 via control pin 4.2.1, and is fully rotated into its final position while the second pinion 6.3.4 is engaged with control disk 6.2.1 and rotates together with it. A pointer pinion 6.3.5 that is always engaged with the two pinions 6.3.3, 6.3.4 and holds the pointer 6.1 is also rotated together with it. In this phase, therefore, pointer 6.1 follows, not only the rotating movement of the clutch disk but also that of the pointer pinion 6.3.5, in synchrony with the second pinion 6.3.4 and with the pointer pinion, respectively; all movements of these parts are symbolically indicated by arrows in
In this first variant of the display means 6 and means for reversal, pointer 6.1 in the above-mentioned first phase in summary at first moves slowly in the direction of the center of the time display device 1, while it follows the rotation of reversing lever 4.3 or control disk 6.2.1 and the associated rotation of clutch disk 6.3.1, this movement being well visible to the wearer. In the second phase, about half an hour before 6 o'clock and before slide 4.1 has reached the upper end of screw 5.3, a jumping and instantaneous movement of the pointer then takes place. That is, starting from a certain angle, the rotation of pointer 6.1 is accelerated when the reversing lever 4.3 hits the upper positioning pin 1.2, and finally, just before pointer 6.1 has completed half a turn, it suddenly is reversed. This is caused, on the one hand by the cooperation of catch 6.2.2 and the recess in control disk 6.2.1 as well as of a dial train catch 6.3.6 and pointer pinion 6.3.5 in the dial train 6.3, and on the other hand by the simultaneous rotation of clutch disk 6.3.1 and of the idle pinions of dial train 6.3 which are arranged on this disk and which have now become engaged with control disk 6.2.1. Thus, pointer 6.1 is now positioned on the opposite scale section by this combined two-phase movement, which can be regarded as a partially jumping and instantaneous reversing movement. The opposite constellation with slide 4.1 at the lower scale end is analogous, but here an intermediate gear 6.3.7 is inserted between the first pinion 6.3.3 and the pointer pinion 6.3.5.
This embodiment thus has display means 6 with a pointer 6.1 which, when reaching one end of a linear scale section 2.1, 2.2 will turn over from one scale section to the other, and in fact only partially in a jumping and instantaneous manner. This implies that the wearer, always during about half an hour before 6 o'clock in the morning and evening or, generally, just before the pointer turns over at the scale's end, will not be able to read the time entirely correctly, since relative to the scale, the pointer during this time is moving in the opposite direction, toward the center of the time display device 1. It may be desirable to avoid this effect, even though within the first few minutes this movement may be hardly noticeable to the wearer.
In the second variant of the display module, this is achieved by arranging the display means 6 on member 4 in such a way that they will turn over to the scale section that is located in parallel, in an entirely jumping and instantaneous manner when reaching any of the ends of a linear scale section 2.1, 2.2. Even here the display means are arranged on member 4, as in the earlier embodiment, advantageously in such a way that the turn occurs in a direction perceptibly pointing toward the center of the time display device 1, but this is not at all disturbing inasmuch as the turning occurs as a single sudden jump.
In this embodiment the means for reversal of member 4 include a pretensioning spring 4.3.2 helping to bring the reversing lever 4.3 via the positioning or release pins 1.2 on frame 1.1 in fractions of a second or at least within a few seconds automatically to the new position at the opposite screw 5.2, 5.3, so that pointer 6.1 is also rotated at once to the other scale section 2.1, 2.2 by the reversing means on the display means 6. Here, structure and function of the display means 6 are basically identical with those already described above in relation to the first variant, and are subject to only one important change, that is, a control of clutch disk 6.3.1 that is independent of reversing lever 4.3 and will be explained below. These two main differences, that is, an independent control of clutch disk 6.3.1 and the addition of a pretensioning spring 4.3.2 for reversing lever 4.3, have the effect that pointer 6.1 will move within the shortest possible time by half a turn from one scale section 2.1, 2.2 to the other. The advantage being that the wearer of the associated watch will practically always be able to exactly read the time, even while waiting for the pointer to jump over. For
For the purpose of achieving the jumping function introduced in a general way above, a guide for instance in the guise of a further rail 3.2 will first be attached at frame 1.1, advantageously behind the guide rail 3.1. This guide, which will be called a control rail 3.2, includes a guide groove 3.2.1 diagonally crossing the surface of guide rail 3.1 facing the dial, as can be seen from
Contrary to the first variant, clutch disk 6.3.1 in the present case is no longer rotated via control pin 4.2.1 but its rotation is controlled via control rail 3.2 by a so-called clutch disk pin 6.3.8, which is integral with the clutch disk 6.3.1 and is engaged in guide groove 3.2.1 of the control rail 3.2 just mentioned. During the linear advance of slide 4.1 from the lower end of frame 1.1 to its upper end along guide rail 3.1, the clutch disk pin 6.3.8 is shifted laterally by the diagonally running guide groove 3.2.1 in control rail 3.2, as shown in
Spring 4.3.2 which may be selected, for instance, as shown in
During the longitudinal movement of slide 4.1, the entire set of interacting parts: crossbar 4.2, reversing lever 4.3, and control disk 6.2.1, is held in place by catch 6.2.2 until a positioning pin 1.2 will act upon an arm of reversing lever 4.3. As soon as the force of catch 6.2.2 is overcome, the control disk 6.2.1 will be released and rotated by the stored energy of pretensioning spring 6.3.8 until catch 6.2.2 will engage into the other notch of control disk 6.2.1 corresponding to the other extreme position of reversing lever 4.3. Finally pointer 6.1 is brought into the correct position by dial train catch 6.3.6 that is engaged into the lobes of pointer pinion 6.3.5, by compensating the relatively large toothing plays. Otherwise, the different parts of the display module move according to the same pattern as explained in the above variant.
Even here, theoretically, pointer 6.1 will at first undertake a slight, oppositely directed movement before the jump to the oppositely located scale section 2.1, 2.2 is triggered. In practice, this backward movement is compensated by plays between the parts and more particularly between the teeth, so that a wearer will only perceive the jumping of pointer 6.1.
Theoretically, the dial train 6.3 on slide 4.1 may be supplemented to any extent desired with other designs. For instance, a minutes pointer may be added, or a rearrangement may be undertaken in order to realize other display functions of a linear time display according to the invention that had been mentioned above.
In a third variant, finally, the display module may have display means 6 that instead of being rotated, can be shifted linearly when executing said turn from one scale section to the other at the end of a linear scale section 2.1, 2.2. In this case the turn is realized, not by a rotary movement but by a linear movement of display means 6 occurring perpendicularly to the direction of movement of the member 4 that is mounted on the guiding means 3.
From the movement of the timepiece up to member 4 or slide 4.1 including the associated crossbar 4.2, the functioning of this variant is basically identically with that of the first two variants. In the following, therefore, only the design of the display means 6 that differs from the embodiments already described, as well as their cooperation with member 4 of the linear time display will be described.
It can be seen from
A lateral shift of the guide beam and of crossbar 4.2, respectively, which as described above at first occurs continuously because of the conical ends of screws 5.2, 5.3 and/or the positioning pins 1.2, and then as a jump, i.e., at least partially in an instantaneous manner because of the action of catch 4.4 at carriage 4.1 shown in
It is symbolically indicated in the top view of
In addition, a direction indicator 4.3.4 filling two functions may be attached to the reversing lever 4.3. The indicator 4.3.4 firstly is used, as already indicated by its name, to emphasize the current position of double pointer 6.4, inasmuch as in the embodiments described, the horizontal shift of the double pointer 6.4 will only be a few millimeters in wristwatches, in view of their small size. In addition, this direction indicator 4.3.4 serves as a spring holding crossbeam 6.5 in its guide groove in slide 4.1. As an alternative, of course, this guide groove in slide 4.1 and/or the shape of the cross section of crossbeam 6.5 could be changed in an appropriate way so as to secure the attachment of crossbeam 6.5. This serves to eliminate unnecessary friction between parts by avoiding a raising of crossbeam 6.5, so that reversing lever 4.3 may pivot more freely about its point of rotation 4.3.1.
In
This third variant of a linear time display may again serve as a minutes display, or in the context of one of the other display functions mentioned above.
It is possible, moreover, to optimize the functioning of a linear time display according to the invention, by a number of improvements of the different parts in all variants described.
On the one hand, crossbar 4.2 may have ends of concave shape adapted to the cross section of screws 5.2, 5.3, as shown in
On the other hand, it is important in such a display device to provide the best possible display accuracy. Where pointers exist for the hours as well as for the minutes, which has not been represented in the figures, the indication of the double pointer for the hours must agree with that of the pointer for minutes, very clearly for instance at 12 o'clock. The display accuracy is also known as display tolerance, and will depend more particularly on the size of tolerances present in the mechanism, primarily the fitting tolerances and the safe distances between parts and groups of parts which are needed to secure the functioning of the display mechanism. As an illustration, we may mention for instance the end play of screws 5.2, 5.3 in frame 1.1, the angular play of screws 5.2, 5.3 that depends on tooth play with the driving gear train 5.1, the tilt play between guide rail 3.1 and slide 4.1, the play between crossbar 4.2 and the helical threads of screws 5.2, 5.3, etc.
It must be guaranteed by possible design options that the display position of the pointer for the hours has at least an accuracy of about ±12 minutes, which corresponds to the distance between marks on an ordinary dial divided into 60 minutes.
At the level of product design already, different measures may be taken in order to counteract potential inaccuracies in the display. For instance, rather than placing line marks having a certain length on scales 2.1, 2.2, one could apply round dots having a larger diameter, or omit the marks altogether. The resulting reading inaccuracy can be balanced by a separate display of the minutes.
At the level of mechanical layout, moreover, one may attempt to keep the tolerances present throughout the mechanism as small as possible so that the accuracy of the display will be affected to the smallest possible extent by shifts between individual parts.
The design solutions that are applicable here may be highly diversified, and often include elastic elements. These have the disadvantage, though, to raise friction between the parts, and thus are in contrast to the above condition to reduce friction between the parts. Therefore, such elastic elements will not be described any further in what follows.
Another possible solution provides for small raised areas 2.1.1, 2.2.1 on the surfaces of time scales 2.1, 2.2 facing the pointer 6.1 or double pointer 6.4, as well as on their surfaces facing the guide rail 3.1, so that the end(s) of the pointer may be supported by said raised areas. This means that during the to-and-fro movement of slide 4.1 along the scale sections 2.1, 2.2 the ends of the pointer will be dragged along the surface of one of the raised areas 2.1.1, 2.2.1, and will be supported by it. This is shown in
As an alternative, again shown in
The same purpose that is served by the above raised areas 2.1.1, 2.2.1 or by plate 3.3, can of course also be served by a guide rail 3.1 having square or polygonal cross section, and matched design of slide 4.1, as shown in the first two sketches in
To counteract tilting, apart from the measures cited above, slide 4.1 may further include at least two friction bearings 4.1.1 such as those commonly used in watchmaking wherever the longitudinal orientation of a part or group of parts requires very high precision. Ordinarily, for reasons of manufacturing technology and cost, the friction bearings 4.1.1 are arranged at the two ends of slide 4.1 between it and guide rail 3.1, as shown for instance in
The cross section of guide rail 3.1 may have flattened portions 3.1.1 on one or several sides, see
It must also be mentioned in the context of friction bearings 4.1.1 and of the cross-sectional shape of guide rail 3.1 that a square or polygonal shape—in contrast to a rail of circular cross section—generally implies the disadvantage of friction bearings 4.1.1 having a two-point support. By three-point spatial support together with the second friction bearing 4.1.1, the risk of tilt thus is raised when tolerances have been chosen that are too narrow, or a larger lateral tilt will be produced when the tolerances are large. It is an additional disadvantage of a square or polygonal guide rail 3.1 that seen in cross section, the orientation of slide 4.1 depends on it, making assembly more difficult. In summary, it may be said in this respect that square or polygonal guides are beset by many technical problems while round guide rails 3.1 cooperating with the slide and friction bearings 4.1.1 offer the advantage in assembly that an alignment of flattened sides 3.1.1 is not required, and thus has no influence on the slide 4.1, its orientation being determined separately, either by the pointer ends or by the lower edges of the slide. Therefore, a tilting of slide 4.1 is practically impossible because of two-point space support in friction bearings 4.1.1 on a rail 3.1 of round cross section.
It is emphasized by these explanations that in a time display according to the present invention, it is clear at all times from the display which scale section is to be read. Moreover, only linear scale sections are visible, which enhances the aesthetic effect. These linear scale sections moreover offer large freedom of design, since the turning motion occurs, either as a rotary motion pointing toward the center of the time display device, or as a linear motion perpendicularly to the direction of motion of the member attached to the guiding means.
Number | Date | Country | Kind |
---|---|---|---|
05026430.8 | Dec 2005 | EP | regional |
01448/05 | Sep 2005 | CH | national |