US1990012A - Clock - Google Patents

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US1990012A
US1990012A US715983A US71598334A US1990012A US 1990012 A US1990012 A US 1990012A US 715983 A US715983 A US 715983A US 71598334 A US71598334 A US 71598334A US 1990012 A US1990012 A US 1990012A
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gear
pinion
ring
clock
hands
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US715983A
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Albert N Woodruff
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    • GPHYSICS
    • G04HOROLOGY
    • G04BMECHANICALLY-DRIVEN CLOCKS OR WATCHES; MECHANICAL PARTS OF CLOCKS OR WATCHES IN GENERAL; TIME PIECES USING THE POSITION OF THE SUN, MOON OR STARS
    • G04B19/00Indicating the time by visual means
    • G04B19/22Arrangements for indicating different local apparent times; Universal time pieces
    • G04B19/223Arrangements for indicating different local apparent times; Universal time pieces with rotary disc, rotary bezel, or rotary dial

Description

Feb. 5, 1935. A. N. WOODRUFF CLOCK Filed March 16, 1954 2 Sheets-Sheet 1 w- 11ml u INVENTOR WITNESSES awed-.7)? Waad'r ATTORN EYS Feb. 5,1935. A. N. WOODRUFF 1,990,012
I CLOCK Filed March 16, 1934 2 Sheets-Sheet 2 ATTOR N EYS Patented Feb. 5, 1935 UNITED STATES PATENT OFFICE CLOCK Albert N. Woodrufi, Washington, D. 0. Application March 16, 1934, Serial No. 715,983
10 Claims.
This invention relates to improvements in clocks, and its objects are as follows:-
First, to provide a clock for determining the time at any designated locality on the globe.
Second, to provide a clock which will continuously tell thelocal time, and which can be simply adjusted so that itshour and minute hands will indicate the time on its dial at any remote point on the globe, provided that the clock is functioning properly and is correctly timed at the locality from which the reading is being made.
Third, to provide an adjustable ring graduated in degrees of longitude east and west of Greenwich, said ring having means for advancing or setting back the clock hands according to longitudes east and west of Greenwich with respect to a fixed mark.
Fourth, to provide a common hand-gear train driver gear which is responsible for turning the clock hands from any one of three sources, for which reason it is herein known as common; first by manual turning of the setting knob, sec- 0nd through mechanical turning by the clockwork, third through adjustment of the graduated ring. by the thumbwheel.
In the drawings:
Figure l is a diagrammatic perspective view chiefly illustrating those parts concerned with the invention, these parts being drawn out of true relationship so that the working can be better understood.
Figure 2 is a detail plan view of the thumbwheel and graduated ring.
Figure 3 is a cross section of the clock, the parts being more nearly in their actual condensed relationship than in Figure 1. A
Persons who navigate vessels and pilot aircraft have need upon occasion for knowing the time of day or night in the locality toward which they are traveling. The common practice among such persons, also with engineers'of trains and persons riding on them, is to set their time pieces either ahead or back as certain points are crossed in traveling either eastward or westward.
These setting points occur along the hour meridians. These are spaced 15 apart, and for every one crossed going eastward the time is set ahead one hour, and for every one crossed going westward the time is set back one hour. The result of this arrangement as far as the United States is concerned, is that the country has divisions respectively of Eastern standard time, Central standard time, Mountain standard time and Pacific standard time. 1
According to this plan any given hour is adopted as the hour in the entire zone between any two hour meridians; For instance if the time is 2:00 P. M. in Washington, D. C. it is also 2:00 P. M. anywhere in the zone between the 75 and 90 meridians. This is quite satisfactory for general working purposes, but the plan is not suitable at all when it becomes necessary for one to know the exact time in a designated locality, because it is obvious that the actual time must vary progressively in longitudes west and east of Greenwich.
Persons making celestial calculations may particularly be required to have the exact local time. That might also be important to a person navigating the ocean to enable him to carry out some calculation or to make an exact record. In cases such as these the foregoing rough estimates of time may not be sufiicient, and it is to meet the need of accuracy that the instant clock has been devised.
Attention is directed to the drawings. A central shaft 1 is adapted to be actuated by the main spring 2 through an intermediate train comprising the gears and pinions 3, 4, 5 and 6. The pinion 6 has a known type of friction clutch 7 combined with it. This clutch is adapted to drive the central shaft through the gear train by power from the main spring, but it is also adapted to slip withreference to the pinion 6 when the setting knob 8 is manually turned. This knob is turned by the fingers of the hand in one direction or the other so as to set the clock-hands according to common practice.
The central shaft 1 makes one rotation every hour when driven by the clockwork 2 to 7. It projects through the entire mechanism and serves as an axle for the upper works presently described. Below the pinion 6 there is a gear 9 which in practice meshes with the usual timing mechanism (not shown), including the escapement. Above the pinion 6, more particularly, above the clutch 7 is a twelve-tooth pinion 10 which meshes with an idler 11 and through the latter imparts power to another twelve-tooth pinion 12 on a countershaft 13 which has aflixed to it a four-tooth pinion 14.
The pinion 14 meshes with the ninety-six-tooth gear rim of a backing plate 15. Tracing the motion from the central shaft 1, the one rotation per hour of said shaft is transmitted to the pinion 14 which also makes one rotation per hour, and since its four teeth mesh with the ninetysix external teeth of the gear 15 it follows that the latter makes one rotation in twenty-four hours.
An internal seventy-two-tooth ring gear 16 is secured to the gear 15 by means 17 which comprise rivets or their equivalents. The gears 15, 16 are permanently fastened together, and the two are herein known as the double gear. Meshing with the internal ring gear 16 is a twelvetooth pinion 18. Above this is a-forty-eighttooth driver gear 19. The gear and pinion are suitably secured together and turn as a unit on a shaft 20 (Fig. 3) which is suitably secured by means 21 to an extension 22 of a one hundred ninety-two-tooth ring gear 23.
The twelve-tooth-pinion 18 rotates six times to each rotation of the double gear 15, 16. It makes these six rotations by the driving power delivered to it from the clockwork 2 etc. or from the setting knob 8. In each of these instances the unit 18, 19 remains stationary relatively to the ring gear 23 although it rotates on its shaft 20. The unit 18, 19 is also capable of being rotated by a thumbwheel at the top. At that time the double gear 15, 16 remains stationary and the unit 18, 19 is both advanced around the gear 15, 16 and rotated by virtue of the planetary motion of the pinion 18 around the internal ring gear 16.
Meshing with the gear 19 is a twelve-tooth pinion 24. This pinion is part of a tube 25 which extends upward and fixedly carries the minute hand 26. One rotation of the gear 19 produces four rotations of the pinion 24, and since the gear 19 makes six rotations in twenty-four hours it follows that the minute hand 26 also makes twenty-four rotations in twenty-four hours. Or, what is the same thing, twenty-four rotations of the minute hand occur for every one revolution of the double gear 15, 16.
In mesh with the pinion 24 is a forty-eighttooth gear 27 which has a nine-tooth pinion 28 (Fig. 3) fastened to its upper surface. This gear and pinion turn upon a pin 29 depending from the dial 30 of the clock. The pinion 28 meshes with a flfty-four-tooth gear 31 which is secured to an easily rotated tube 32 mounted on the tube 25. The tube 32 has the hour hand 33 aflixed to it in any desired way, for example by means of a thin collar 34 (Fig. 3) compressibly fastened on the upper end of the hour hand tube.
Since the forty-eight-tooth gear 27 meshes with the twelve-tooth pinion 24 the former represents a reduction of four. The fifty-four-tooth gear 31 meshing with the nine-tooth pinion 28 represents a reduction of six. The two reductions represent a total of twenty-four which causes the hour hand 33 to rotate once in twentyfour hours.
The upper plate 35 of the clock frame (Fig. 3) fixedly carries a plurality of guide pins 36 which are grooved at 37 to receive and guide a supporting ring 38. This ring is adapted to turn in either of two directions, and it is peripherally guided by the grooves 3'? in turning. Rivets 39 fix the previously mentioned ring gear 23 to the ring 38 and in spaced relationship thereto. The ring gear 23 has guide pins 40 fixed on it. These are similar to the guide pins 36, and being so have grooves 41 to receive and guide the smooth internal periphery of a one hundred eighty-fourtooth differential ring gear 42.
This gear 42 has a ring 43 secured to it by means of rivets 44 which also serve as spacers. The ring 43 is adjustable or turnable in either of two directions. It is graduated at 45 in degrees beginning at 0 (Fig. 2) and numbering to 180, reading both ways, thus serving as an index as to how far to move the ring. If desired the readings can be graduated to read from 0 to 360 degrees either way, but the illustrated mode of graduation is deemed preferable because it conforms with the customary way of marking off the degrees of longitude west and east of Greenwich.
The 0 graduation represents the 0 meridian running through Greenwich. The graduations on each side are to be read as degrees of longiture west and east of Greenwich down to the 180 meridian which is the International date line. For the purposes of the invention those graduations on the right of 0 (Fig. 2) numbering to 180 are regarded as degrees west of Greenwich and are appropriately marked at 46 with an arrow and W. Similarly the graduations to the left of 0 numbering to 180 are regarded as degrees of longitude east of Greenwich and are ap propriately marked at 4'7 with an arrow and E.
An eight-tooth (more or less) pinion 48 (Fig. 3) meshes with the gears 23, 42. The shaft 49 of this pinion has suitable bearings on the framework of the clock. The shaft fixedly carries a thumbwheel 50 which is preferably knurled to make turning easy and constitutes adjusting means by which the ring 43 is moved. Turning of the thumbwheel causes turning of the graduated ring 43, and in order to aid accurate registration of the graduations 45 of either west or east longitude with a fixed mark said wheel has designations 51, 52 comprising an arrow and the letters W and E. The arrow of the designation 51 points clockwise, while the arrow of the designation 52 points counter-clockwise.
A window 53 in the clock dial 30 makes only a few of the graduations 45 visible at a time, the ring 43 being situated beneath said dial. I A line 54 (Fig. 1) is run vertically across the face of the dial 30, and that part 55 of the line which appears above the window 53 is taken as the fixed mark with respect to which the graduations 45 are to be read. The dial 30 is capable of being removed, but for the purposes of removal and subsequent proper centering upon replacement it has depending lugs 56 (Fig. 3) which fit in cut out places 57 in the flange of an annulus 58 which is to be regarded as part of the clock frame. One of the lugs and its out out place may be over sized so that the dial can be emplaced only in the required predetermined position.
The dial 30 is a twenty-four hour dial, its numbers 59 running from 1 to 0. The margin is further numbered at 60, these representing five minute divisions. running consecutively from 5 to 55 they run from 5 to 30 (30 denoting the half hour) then from 30 back to 5. The first set of numbers is to be read in minutes after the hour and the second set in minutes before the hour.
The 0 is to be regarded as in the window 53, and it is the twenty-fourth hour. 0 is also regarded as midnight. The numbers at the right of the line 54 designate the morning hours from midnight to noon, while those on the left of the line designate the evening hours from noon to midnight. The right and left sides may be marked am. and pm. The right and left sides may also be made white and black respectively, the numbers on the right being printed in black and those on the left in white. These are merely suggestions, and it is to be regarded as within the province of the invention to make any desired color or number combinations.
The operation is readily understood. Consider first the manual setting of the hands 26, 33. The setting knob 8 can be turned in either direction. Turning is imparted to the central shaft 1, and the latter slips in the friction clutch 7 without afiecting the gear train 3-6. Turning of the knob 8 can be traced through the train 10, 11, 12 to the pinion 14, the turning of which moves the double gear 15, 16 either clockwise or counter-clockwise. Although the pinion-gear unit l8, 19 remains Instead of these numbers relatively stationary it turns on its shaft 20 by the motion of the double gear, the turning of said unit being imparted to the hands 26, 33 through the hand gear train 24, 27, 28, 31. I
Consider second the normal operation of the clock through mechanical turning by the clockwork. Regarding the spring 2 (Fig. 1) as being wound, driving power is delivered to the central shaft 1 by the intermediate gear train and clutch 3 to 7. The central shaft has nothing to do with driving the works above the pinion 10 (Fig. 3). It merely acts as an axle, but said works are driven from the central shaft by the gear train 10, 11, 12 and 14.
Clockwise turning of the pinion 14 causes counter-clockwise turning of the double gear 15, 16. The unit 18, 19 is stationary relatively to the ring gear 23 because it is carried bythe ring 'gear 23 and that gear, as well as the ring 38,
gear 42 and graduated ring 43, remains stationary during the normal operation of the clock.
Since the double gear 15, 16 is turning counterclockwise the unit 18, 19 is also turning counterclockwise by virtue of its pinion 18 meshing with the teeth of the ring 16. The counter-clockwise turning of the gear 19 causes clockwise turning of the pinion 24, counter-clockwise turning of the pinion 28 and clockwise turning of the gear 31. The tube 25 of the pinion 24 moves the minute hand 26 one dial rotation; each hour,
while the reduction of the double gear train 24, 27 and 28, 31 turns the tube 32 of the hour hand 33 one twenty-fourth of the dial circumference per hour.
Consider third the operation of the clock for determining the time at any designated remote locality, this feature being the actual invention. The calculation is made from Washington, D. C.
-which is located near the 77 meridian west longitude (west of Greenwich). The clock is supposed to be functioning properly and to be correctly timed. Consider the Washington time as being 8:00 A. M. as indicated in Figure 1.
. Set the graduated ring 43 so that the graduation which designates 77 west longitude (Fig. 2) registers with the fixed mark 55. All readings of longitude west of Greenwich are to be read on the ring to theright of according to the marking 46 (Fig. 2). Should the operator forget whether the west or east graduations are under the window 53 he would turn the thumbwheel 50 until the markings 46, 47 become visible. Then having determined the class of graduations which he wishes to use in his calculations, that is to say, whether in west or east longitude, he will turn the thumbwheel until the desired degree setting registers with the mark 55. Should, perchance, the clock hands be set to indicate erroneous local time in this performance they can be properly set by use of the setting knob 8.
It is desired to know the corresponding time in Honolulu, Hawaii. Honolulu is situated between the 150 and 165 meridians. Since Honolulu is west of Washington the thumbwheel 50 must be turned clockwise to agree with the designation 51. This causes a counter-clockwise turning of the graduated ring 43, and the turning should continue until the graduation 150 registers with the mark 55. The clock hands will point to 3:00 A. M., and that is caused in this way:-
As the thumbwheel 50 is turned clockwise the pinion 48 causes simultaneous counter-clockwise turning of the ring 43, gear 42, gear 23 and ring 38. Since the unit 18, 19 is carried by the gear 23 and the double gear 15, 16 is incapable of turning because of the resistance of the gear train tracing back from the pinion 4, it follows that the unit 18, 19 will partake of a planetary motion around the double gear, turning clockwise all the while by virtue of its pinion 18 meshing with the gear 16.
Clockwise turning of the driver 19 causes counter-clockwise turning of the pinion 24 and of its carried minute hand 26, also counter-clockwise turning of the gear 31 and its carried hour hand 33. The clock hands are thus set back, the time being earlier the farther west the reading is taken.
Reverting to the determination of time in Honolulu, the result given above is the time between the 150 and 165 meridians West longitude at 8: 00 A. M. in Washington, D. C. However, Honolulu is located on a line approximately 157 west of Greenwich. Upon turning the thumbwheel 50 clockwise until the graduation 157 appears in the window 53 in registration with the fixed mark 55 it wil be found that the clock hands denote 2:32 A. M. This is the exact time reading for the remote locality, and as has been brought out before the purpose of the clock is to enable the determination of the exact time reading for any designated remote locality for the purpose of calculation.
In each of the foregoing three operations, first by means of the setting knob-8, second by means of the main spring 2 and third by means of the thumbwheel 50 the unit 18, 19 operates the handgear train to move the clock hands. The piniongear unit 18, 19 thus serves as a common driver unit or means, and is so termed hereinafter. When the common driver unit is rotated by the clock work it properly rotates the minute hand 26 twenty-four times in twenty-four hours. As long as theclock is operated as an ordinary clock, that is to say as long as the hour and minute hands 33, 26 are made to traverse the dial by spring (2) power, the intervening planetary gearing 16, 18, 19, 24 functions correctly to produce a twentyfour hour cycle of the hands in a twenty-four hour period.
In the absence of the differential ring gear 42 this same gearing is found to possess a fault, apparently not subject to correction, when operated from the thumbwheel 50 to work the clock hands. At that time the clock hands will indicate the passing of twenty-five hours in a twentyfour hour period, and that period is determined by turning the graduated ring 43 through a 360 revolution, during which revolution the clock bands will indicate twenty-five hours as stated.
Now by interposing the differential gear 42 a correction is made in this manner: The graduated ring 43 is attached to the differential gear, and the gears 42, 23 are geared together by the thumbwheel pinion 48. Since the gear 42 has fewer teeth than the gear 23 it will turn faster by in one revolution than the gear 23, thereby making the graduated ring catch up at the end of 360 of movement with the clock hands at the end of a twenty-four hour cycle.
I claim:
1. A clock comprising hour and minute hands and a numbered dial traversable by the hands,
a clockwork for turning the hands, said clockwork including a main spring and gearing, graduated means having graduations representing divisions of longitude on the globe, and means for moving the graduated means and simultaneously moving the hands with respect to said gearing so that they traverse the dial irrespective of the clockwork.
2. A clock comprising graduated means which has graduations representing divisions of longitude on the globe, a dial and a fixed point thereon, means for moving the graduated means so that'its graduations pass said point and can be registered therewith, hour and minute hands and setting means by which said hands can be set in any time-indicating relationship with respect to the dial, and means for turning the hands simultaneously with moving the graduated means and irrespectively of said setting means.
3. A clock comprising hour and minute hands and a dial therefor, clockwork including gearing for causing the hands to traverse the dial according to local time, adjusting means to turn the hands irrespectively of said gearing for making a setting according to corresponding time at a distant place, and a ring having numbered gradu ations agreeing with the divisions of longitude onthe globe and being turnable simultaneously with the turning of the hands by said adjusting means and providing an index as to how far to adjust said adjusting means.
4. A clock comprising a main spring and driven gear train culminating in the externally toothed gear of a double gear which includes an attached internally toothed ring, hour and minute hands and a gear train for said hands, driver means being the intermediary between the double gear and the hand-gear train, said driver means consisting of a pinion in mesh with the toothed ring and a gear in mesh with a terminal pinion of said train and operating said gear train by turning of the double gear, a graduated ring having numbered graduations agreeing with the divisions of longitude on the globe, means by which the driver means is carried by said ring, and means to turn the ring, its graduations serving as an index as to how far to turn, said turning causing a planetary motion of the driver means around the double gear and a turning of said hands independently of the clockwork gear train.
5. A clock comprising a driver gear, clockwork culminating in a double gear which consists of an externally toothed gear and an attached internally toothed ring, said clockwork including a pinion meshing with the externally toothed gear, a pinion on the driver gear meshing with the internally toothed ring whereby the driver gear is turned by power derived from the clockwork, hourand minute hands, and a gear train for said hands, one of the gears of said train meshing with the driver gear.
6. A clock comprising hour and minute hands, a gear train for said hands, a dial for the hands, said dial having a fixed mark, a graduated ring having numbered graduations agreeing with the divisions oi longitude on the globe, means to turn said ring so that its graduations can be registered with said mark, a relatively stationary gear, driver means in mesh with the hand-gear train and including a pinion in mesh with the relatively stationary gear, and means by which said driver means is carried by the ring.
'1. A clock comprising hour and minute hands, a gear train for turning the hands, a driver unit consisting of a gear in mesh with the hand-gear train and a pinion, a relatively stationary gear in mesh with said pinion, two ring gears with a dissimilar number of teeth, the one having the most teeth having means carrying the driver unit, a thumbwheel having a pinion meshing with both ring gears for turning them simultaneously and causing said unit to partake of planetary motion with respect to the relatively fixed gear and simultaneously operate the hand-gear train, anda graduated ring fixedly carried by the ring gear having fewer teeth, said ring and its gear partaking of a differential motion with respect to the other ring gear.
8. In a clock, hour and minute hands, a gear train for turning said hands, a setting knob and central shaft, a pinion-gear driver unit of which the gear is in mesh with the hand-gear train, connected internal-external gears consisting of a double gear having one of its gears in mesh with the pinion and a gear train between said shaft and the double gear, said train including a pinion on the shaft and a pinion in mesh with the other gear of the double gear.
9. A clock comprising hour and minute hands, a gear train for working the hands, plural means for severally operating the hand-gear train, said plural means consisting of a manually turnable means and a clockwork, a driver unit which is the intermediary between the hand-gear train and each of the plural means and therefore common to each of said plural means, the common driver unit consisting of a gear in mesh with said train and a pinion, a double gear of which internal teeth are in mesh with the pinion and on which there are external teeth, a gear train in driving connection between said external teeth and the clockwork for rotating the common driver unit, and means by which said unit is rotatably carried by said manually turnable means which, when turned, causes a planetary motion of said unit with respect to the double gear.
10. In a clock, hour and minute hands and a gear train for turning said hands, a shaft which has a pinion fixed on it, a driven gear train in mesh with the pinion and culminating in the externally toothed gear of a double gear which includes an attached internally toothed ring, separate means which constitute two power sources for working the hand-gear train, one of said means being a manually operable setting knob on the shaft, the other means being a clockwork geared up to the shaft to turn it in substitution of the setting knob, andcommon driver means for transferring the power either from one source or the other to the hand-gear train, said means consisting of a gear in mesh with'one of the gears of the hand-gear train, and an attached pinion in mesh with the internally toothed ring.
ALBERT N. WOODRUFF.
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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5107468A (en) * 1990-06-12 1992-04-21 Lu Jem D Structure of world time clock for 24-hour indication
US5197043A (en) * 1991-03-29 1993-03-23 Strader Verne A Night and day earth clock calendar
US5745440A (en) * 1996-07-17 1998-04-28 Chen; Eddie Zon Tsu Time equipment with time zone mechanism
US20090175130A1 (en) * 2007-12-19 2009-07-09 Beppo Hilfiker Device for operating an electronic multifunctional device
CN103064278A (en) * 2011-10-21 2013-04-24 王鼎精密股份有限公司 Timer movement with world time zone display

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5107468A (en) * 1990-06-12 1992-04-21 Lu Jem D Structure of world time clock for 24-hour indication
US5197043A (en) * 1991-03-29 1993-03-23 Strader Verne A Night and day earth clock calendar
US5745440A (en) * 1996-07-17 1998-04-28 Chen; Eddie Zon Tsu Time equipment with time zone mechanism
US20090175130A1 (en) * 2007-12-19 2009-07-09 Beppo Hilfiker Device for operating an electronic multifunctional device
US7794138B2 (en) * 2007-12-19 2010-09-14 Beppo Hilfiker Device for operating an electronic multifunctional device
CN103064278A (en) * 2011-10-21 2013-04-24 王鼎精密股份有限公司 Timer movement with world time zone display
EP2584412A1 (en) * 2011-10-21 2013-04-24 Atop Precision Ind. Co., Ltd. Timer movement with a display for world time zones
JP2013088428A (en) * 2011-10-21 2013-05-13 Atop Precision Ind Co Ltd Timer movement
CN103064278B (en) * 2011-10-21 2015-04-29 王鼎精密股份有限公司 Timer movement with world time zone display

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