GB2345352A - A large date display mechanism - Google Patents

Abstract

A date display mechanism comprises separate units 11 and tens 12 counters, the tens counter being toggled once for every one revolution of the units counter by a pin (24). The Units Ring 11 has a masking lever 13 that co-operates with a cam 26 when the tens is indicating digit three and the units is indicating digit one displaying the 31st of any month. This particular condition also causes lever 14 not to act on the units Ring and to instead advance the tens counter by one division with pin 31 of lever 15 meshing with lever 27.

Description

LARGE DATE DISPLAY MECHANISM for clocks, watches & timers.

This invention relates to a Large date display counter mechanism particularly suited for indicating or displaying the date on mechanical clocks, watches & timers.

Date display mechanisms are useful additions to common mechanical or quartz clocks and watches. Most date mechanisms are particularly designed to display the date as an additional feature to the basic timing function of mechanical clocks and watches. The date is usually displayed in a separate window on the clock face or dial, or with the help of an auxilliary dial or dials. These mechanisms are usually kept simple in design and most need correction during months with less than 31 days.

Date mechanisms are usually implemented in the form of a disk or ring having 31 divisions, where the disk or ring is advanced by one division every 24 hours. The disk type of method usually has a date display handand printing all the 31 date numbers is difficult because of the lack of space.

In the date ring system, numbers from 1 to 31 are printed on the date ring which is also limited by the size of the dial or watch case. This results in a very small date window that usually has to be provided with a magnifing aperture to make the date more easily visible on the smaller watches.

If the date mechanism is implemented in the form of separate 'units'and'tens'counters, then a significantly larger date display mechanism can be acheived. However special problems arise when the date needs to change from 31 to 1.

A date display that makes use of separate'units'and'tens' counters permits a display that is more than three times the size of a conventional date mechanism, given the same amount of available space.

The object of the present invention is to provide a Large Date Display Mechanism that is implemented as a counter with separate overlapping'units'and'tens'counting disks.

According to the present invention there is provided a A Large Date Display Mechanism comprising a Units Ring (11) of ten equal divisions indexed by a notch on each division, the said Ring (11) being advanced by one division once every twenty four hours by a lever (14) mounted on Drive lever (16), the said Drive lever (16) operating co-axially with a Trigger lever (18) activated indirectly by a cam (37), and the said Units Ring (11) fitted with a pin (24) that toggles Star wheel (25) once for every one revolution of the Units Ring (11), the said star wheel (25) mounted rigidly and co-axially with cam (26), and finger (27) being also co-axially mounted but free to rotate partly anti-clockwise about its axis on axle (12) governed by the stud and spring (28), and the said axle (12) carrying a'Tens'display disk (49), and the and the said cam (26) co-operating with lever (13) when they come together at one position so as to mask a notch on the Units Ring (11), and another lever (15) fixed rigidly to lever (14) having a pin (31) that swings inward into the meshing radius of lever (27) when the finger of lever (14) rests on, or slides against the inner radius of Units Ring (11), the Said Units Ring (11) carrying a'Units'display Disk (50) mounted on legs or supports (33).

Positional locking of Units Ring (11) and Tens Axle (12) is provided by springs (23) and (47) respectively.

A lever (13) is provided on Units Ring (11), and restricted in its freedom to move by limiting studs (29) and (30), and maintained in a position of rest by restoring spring (32), the portion of the said lever closer to stud (29) being at a level that enables co-operation with the finger of lever (14) as well as serving to mask the notch on Units Ring (11) when required.

The portion of lever (13) closer to stud (30) is at a level higher than the finger of lever (14) and designed to co-operate with cam (26) as and when required.

A specific embodiment of this invention will now be described by way of example with reference to the accompanying drawings wherein : Figure 1. is a plan view of the various essential components of the invented'Large Date Display Mechanism'.

The components in actual possible layout showing the co-operation of various levers and other components.

Figure 2. is an elevation drawing depicting the essential components at their various levels of co-operation, but not any specific sectional view.

Figure 3. is a plan view similar to Fig 1. but showing the position of the cam (26) locking Masking Lever (13) and Tens lever (27) ready to be advanced by pin (31) of lever (15).

Figure 4. Shows an exploded plan view of the various components that are assembled on Tens Axle (12).

Figure 5. Shows a typical display using separate'Units' (50) and'Tens' (49) disks partly overlapping to provide a composite double digit counter.

With reference to Figures 1 & 2, the'Large Date Display Mechanism'comprises a Units Ring (11) divided into ten equal divisions, each of which is identified by the presence of a notch which serves also as a means to rotate the said ring.

At the centre of the'Units Ring' (11) is the'Drive Lever' (16) that is free to move within a 36 degree sector, that is needed to rotate the'Units Ring' (11) by one division.

The'Drive Lever' (16) works in conjuction with lever (18) so as to provide the detached action required when an indipendent setting mechanism is implemented using (19), (43) and (45).

Arm (20) of lever (18) serves as the trigger finger as well as a stop when it rests against the stud (21) of spring (22).

Cam (37) makes one revolution counter clockwise every twenty four hours lifting Trigger Lever (34) against the action of Trigger Spring (40), via spring loaded pawl (35) & (36), (that is provided as a safety feature in case Cam (37) is driven clockwise by the time setting mechanism or for any other reason).

When pawl (36) drops off the high point cam of (37), lever (34) forces tirgger finger (20) to cause lever (18) to rotate clockwise. Lever (16) also rotates clockwise forced foward by pin (17) untill lever (16) is stopped by stop pin (42).

Restoring spring (22) is fully tensioned and returns the levers (16) and (18) as the action of cam (37) again lifts lever (34) during the course of the next twenty four hours.

The action of Drive Lever (16) is thus instantaneous in the clockwise direction and gradual in the counter clockwise direction.

The clockwise rotation of Units Ring (11) is effected by lever (14) that has a finger that is forced into a notch on Units Ring (11) by spring (41) and is locked into position untill lever (16) completes its 36 degree swing. On the return action of lever (16), the finger of lever (14) is dragged out of the notch and then dragged back till it moves into the next available notch.

The action so far described serves to explain how one revolution of the cam (37) causes the Units Ring to advance by one division, the action repeating every twenty four hours as the cam (37) is ideally fixed to day wheel (38) driven by an hour wheel (39) of any clock or watch mechanism.

The rotation of the Tens Axle (12) is affected by pin (24) fixed on the Units Ring (11), positioned relative to unit number NINE (9) on the said Ring as well as the Units Display Disk (50).

Pin (24) meshes with one tooth of star wheel (25) causing it (and the entire assembly minus spring (47) shown in Fig. 4.) to rotate by 90 degrees or by one tens division.

This action occurs once for every one rotation of Units Ring (11). The Tens Axle moves to represent the Tens digits Zero, One, Two & Three. The protrubent portion of Cam (26) on the the Tens axle moves over the Units Ring (11) when the Tens Axle (12) is to indicate the'Tens'digit Three on the Tens Disk (49).

The entire assembly shown in Fig. 4 (excluding spring (47)) is rigidly fixed to the axle (12) except for lever (27) which can freely rotate about its axis. The degree of rotation is however restricted by Stud and spring (28), mounted rigidly on the cam (26) as shown. This keeps the lever (27) normally locked in position against the stud (28) and provides a degree of freedom to rotate anti-clockwise if toggled in that direction, but is immediately restored to its position of rest on being released.

Since this counter is designed to display the date which never has to go above thirty one days, the counter needs to be reset to digit One (1) after thirty one has been displayed.

This implies that the Units Ring (11) has to be held stationary and the Tens Axle (12) needs to be advanced to the next digit ie. Zero or Null. This unusual condition is effected as described below.

When the Tens Axle (12) is indicating the digit Three, and the Units Ring (11) when advanced relative to Unit Digit One causes the upper portion of the Masking Lever (13) (normally in a position of rest against pin (30)), to remain locked against pin (30), while the lower portion of lever (13) masks the notch on the Units Ring (11) as shown in Fig. 3. The protrubent portion of Cam (26) affects the locking of Lever (13) against the action of the finger of lever (14) trying to enter the notch on Units Ring (11).

This action only occurs when Lever (13) is locked by Cam (26) as depicted in Fig. 3 where the Tens and Units are indicating Three and One respectively.

Levers (14) and (15) are rigidly attached together and move about a common axis, both being controlled by spring (41).

The finger on lever (14) when masked by lever (13) causes the lever assembly of (14) and (15) to swing inwards bringing pin (31) of lever (15) into meshing radius with lever (27) as shown in Fig. 3.

When levers (14) & (15) are being drawn back by lever (16) slowly moving anti-clockwise as cam (37) raises lever (34), the finger of lever (14) is pulled out of the notch and slides along the inner edge of the Units Ring (11). This action also brings pin (31) into the meshing radius of lever (27) which would toggle lever (27) (and the entire Tens Axle) in reverse. Lever (27) is thus mounted on Axle (12) being free to rotate anti-clockwise to a certain extent governed by restoring spring and stud (28), which also serves to lock the said lever (27) while it is rotating clockwise. This action allows pin (31) to pull lever (27) gently drawing it anticlockwise untill it disengages from pin (31) and is restored to its original position by stud and spring (28).

The date transition from Thirty One to One, as implimented in this counter mechanism is described below.

The next foward (clockwise) advance of the Drive Lever (16) will rotate the Tens Axle (12) using lever (27) toggled by pin (31). The Units Ring (11) will however remain stationary as the finger of lever (14) will slip past the available notch that has been masked. In all other combinations of Units or Tens, the finger of Lever (14) forces itself into an available notch causing pin (31) to move out of meshing radius with lever (27). The Tens Axle (12) is rotated only by toggling star Wheel (25) by pin (24) for all other counter operations.

Lever (27) is only in position when the protrubent portion of cam (26) is over the Units Ring (11), representing the Tens digit Three, which allows for the representation of the numbers 30 and 31.

Lever (13) and cam (26) are also operational in their masking and locking roles only at one position as shown in Fig. 3, this period representing the date 31.

A rapid date setting mechanism is implimented using the finger (19) of lever (18) along with levers (43), (45) and (52). Lever (52) provides an external setting mechanism that is activated by pressing the projection on it. The action is magnified causing lever (45) guided by pins (44) to act on lever (43). Due to the ratio of the length of the arms of lever (43), lever (45) first forces lever (19) to rotate counter clockwise against the action of spring (34) acting on finger (20) untill stopped by stud (21).

Further pressure on lever (45) causes the long arm of (43) to act on the Drive lever (16) causing it to rotate clockwise untill stopped by pin (42). This action causes the counter mechanism to increase its count by one as described earlier.

A slower means of setting is via the time setting mechanism (not shown) that causes the hour wheel (39) and Day wheel (38) to affect the setting by using the existing trigger mechanism using cam (37) and lever (34).

The Large Date Mechanism is operated as follows: The Date is initially set by repeatedly using the rapid setting lever (52), by pressing on the short extension, untill the counter displays the required Date. No further action is required as the entire operation of this counter mechanism is controlled by the Clock or watch movement via the hour wheel (39) and day wheel (38). The Time setting button may also be used to initially set the counter mechanism but it may require advancing the time display from a few minutes or upto Twenty four hours to advance the date by one count.

The Large Date Mechanism needs to be advanced manually at the end of short months ie. months with less than 31 days. Either of the setting procedures described above could be used to correct the Date.

Claims (5)

Claims.
1. Claim 1.

   A Large Date Display Mechanism comprising a Units Ring (11) of ten equal divisions indexed by a notch on each division, attached to a Units Display Disk (50), the said Ring (11) being advanced by one division once every twenty four hours by a lever (14) mounted on Drive lever (16), the said Drive lever (16) operating co-axially with a Trigger lever (18) activated indirectly by a cam (37), and the said Units Ring (11) fitted with a pin (24) that toggles Star wheel (25) once for every one revolution of the Units Ring (11), the said star wheel mounted rigidly and co-axially with cam (26), and finger (27) being also co-axially mounted but free to rotate partly anti-clockwise about its axis on axle (12) governed by the stud and spring (28), and the said axle (12) carrying a'Tens' display disk (49), and the and the said cam (26) co-operating with lever (13) when they come together at one position so as to mask a notch on the Units Ring (11), and another lever (15) fixed rigidly to lever (14) having a pin (31) that swings inward into the meshing radius of lever (27) when the finger of lever (14) rests on, or slides against the inner radius of Units Ring (11).
2. Claim 2.

   A Large Date Display Mechanism as claimed in Claim 1. wherein the means of advancing the Units Ring (11) serves as a means to advance as the Tens Axle (12) when required, the said means being in the form of two Levers (14) & (15) being constructed singly or severally, but functioning together as a single unit.
3. Claim 3.

   A Large Date Display Mechanism as claimed in Claim 1. and Claim 2. wherein the means to advance the Units Ring (11) as embodied by lever (14), can be rendered inoperative in its function to advance the Units Ring (11), by a controlling lever (13) mounted on the said Units Ring (ll), the said lever (13) being locked against stop pin (30) by the action of Cam (26), the said cam (26) only causing effect at one possible position i. e. when the Tens Axle (12) and Units Ring (11) are relative to, display digit disks (49) & (50) displaying Three & One respectively or specifically as depicted in Fig 3..
4. Claim 4.

   A Large Date Display Mechanism as claimed in Claim 1., Claim 2., and Claim 3. wherein a cam (26) serves to lock the controlling lever (13) against the action of the finger of lever (14) attempting to enter a notch on the Units Ring (11) causing the entire lever assembly consisting of levers (14) & (15) to swing inwards into the meshing radius of lever (27), thereby serving to toggle lever (27) on the foward or reverse action of the levers (14), (15) & (16), at only this one position when the Tens Axle (12) and Units Ring (11) are relative to display digit disks (49) & (50) displaying Three & One respectively or specifically as depicted in Fig 3.
5. Claim 5.

   A Large Date Display Mechanism as substantially described herein with reference to Figures 1,2,3 & 4 of the accompanying diagrams.