US1620980A - Device for indicating time - Google Patents

Description

March 15, 19271,

F. c.' MEACHAM DEVICE FOR INDICATING TIME Filed April 27, 19 .5

BY M

H15 ATTORNEKS these spaces are again preferably dividech, asby the lines 23, 2A,.into-four equal parts, The lines 22, aswell as the outer extremities of: the two diameters; may be numbered, as indicatedlatii27, ingthe'same manner: as'the- Patented Mar. 15, 19

' FREDE'BICK'O. MEA'CHA'M, or GARDENCITY,"NEw YonK.

DEVICE ron nmron'rrne TrME:

Application; filed .Apri1.27, 1926: SeriaLNo. 104 937.

invention relates t'ov a device for use lHr'tlle determining; of time by observing the this IS acco1nposition of certain. stars; plished': by setting my device, so that the relative position. of the stars, followed by certainv calculations; or by. direct readings indicate thetime when the observations are m'atde,.. as will be hereinafter fully set: forth. Theobject'tofr my invention is to producea simple. and inexpensive device which will permit the. quick and easy determination of the relative positions of the North Star and th'e "Pointers in Ursa Major wlth a remarkable degree of. accuracy underathe conditions'in which the devicev is ordinarily used; anotherobject. of -my invention is to providea device fon suchlpurpose an'd other.

purposes. such as those relating to navigation, which shalllbe: compact: and easily portable and which. at the same time may be capable of. refinement inaccuracy ofmanufacture for. various-uses: 1 1

Figal: of the; accompanyingdrawing is a;

plan viewofi one fornr off my. device and indicates a:method.ofi.usingthe device.- Fig; 2 is a planview of' an improved modification thereof; r

This application is a; continuation in-part ofinry prior app-licationzfiled November 13, 1925-,aS'eria llN0; 68 815, inrwhichthe device; of Fig. l. is fullyillustrateds and described.

In Fig 1 of the. drawing. 21 represents a disk;which may be of transparent. material, such as. celluloid: The disk. is preferany divided into four equal sectors by the perpendicular"diameters 25, 26'. The periphery ofi'thez disk isalso divided. into twelve equalispacess by the. diameters and the lines indicated v at52'2 or by other suitable meansfor indicating the. divisions; ofv the disk;

dial of a clock, from 1 to. 12 inclusive. A-tthe outer: end of one diameter, adjacent the numeral. 12; I prefer to' place. anoutwardly pointing arrow'-head,ior other easily noticeable mark 28'. to. indicate clearly: the uppermost point of the disk which corre-;

sponds to the zenithi Inthis form of the. device, a central aper- 30v which may betransparent. The arm;

when extended, projects beyond the outer I edge of the disk. The eyeletlis: riveted over a portion of the 311211 tolhold it inrotatable relation 1 tothe disk. The eyelet-29 ispreferably atrue eyelet- -i. e.,.of such character;

and convenience in carrying. The longitn dina-lv center of therarm. is defined, .as by the I It willlbeunderstoodthat thisw smerely for compactness-5' line 32, which preferably extends-from the: f

outer end ofthe arm to a pointwhich (when thearm is: fullyextended);meet's or crosses the edge of the disk.v It=wil1ofcourse:be

understood that other suitable means may; be used to define; by-means; of: the-arm,. a radlal l1ne:;;for example, the: outer end of the arm may beofi'set so that; one. edge".

thereof liesalong. a radius: (extended) of the disk. H

my device; this: method enables an surprisingly accurate. calculation. of time, at. least when used at or' near a line of: longitude which determines the standardtime forthat locality.v Of course, when my device isused' at some. distancereast or west ofxsueh linen.

$5 I will now describe one methodbfusing? of longitude, the calculated time will notagree so well with the standard-time but it will everywhere agree very-"closely-rwith the, truetime or sun-time; e In the. method here described; 1 device is-used to determine'the'relative'position of the North. Star or Polaris :and. the two stars in the constellation Ursa Major'krrown asi- Alpha and Beta orthe.fPointers?.-

device" is .held: before the eyesof the: ob

server-.say eight inches. from the eyes-,

with the arrow-head 28 pointing:towardthe: zenith and the diameter 25 in vertical p'o'si tion. The presence of the two diameters on: the face of the disk assists the observer in properly'positioning! it. The disk shouldLbe' held so as to lie in: afplanei perpendicular to. the line of vision. between: the observer: and Polaris- The arm 3O having 'been full-y extended; the device is then so-positi-oned ture isi stamped out of the material 20fthe disk and I a small metalli eyeleti 29' inserted. therein: Carried :by the-eyelet'QQ is an arm 1 that Polaris is visible through the hole at the center ofv the disk-as indicated at 33 in the drawing. The arm 30 is then rotated,

without disturbing the position of the disk,

until the Pointers "of the constellation Ursa Major, indicated at 34,35, lie along the line 32 or the line 32 if continued. This adjustment having been made, the relative position of the stars is read by taking the reading on the disk as determined by the position of the line 32.

Suppose, for example, the reading is, as.

indicated in :the drawing, approximately 1 suppose also that the reading is taken on August 8 in any year. Then to determine the timethe following calculations are made: Start with the readingin this case,

' 1 add to that the number of months and the fraction that have elapsed during the calendar, year in this case 7 4 (January to July, inclusive, being ,7 and the eight. days of August being approximately one quari ter) the sum then equals 8%; next, double so that the net result will be less than 12.

Proceeding thus in the example given, 12 is deducted from 22%, leaving 10%'wh ch 7 means that the time is 10.45.

The modified 'I'orm illustrated in Fig. 2 of the drawings is based upon the same prin ciples above described in connection with Fig. 1 of the drawings. In this device, however, it is unnecessary to calculate'time in hours after the readings of the disk have been made. i

Referring to Fig. 2, the numeral 41 indicates a disk similar to that of 21 in Fig. 1, and may be 'made of any suitable sheet material having the necessary degree of stiffness. The margin of this disk however, is divided into twenty four equal parts numbered as two series of 12 each, representing. thetwo sets of 12 hours ofany one day, as indicated at 4243. The spaces between the longer hour marks may be divided into four parts, indicating quarter hours or any number of corresponding parts indicating other fractions of an hour. Within the outer margin of the disk 41 is a second series of divisions, the main portions of which constitute 12v spaces representing the twelve months of the year from J anuary to December, as indicated by the numerals 44. The

spaces between the longer lines forming these divisions are preferably divided into six equal parts, which correspond respectively to the 5th, 10th, 15th, 20th and 25th days of the respective months. Obviously, these divisions may be arranged to cover shorter periods, depending upon the size of the apparatus in which they are embodied.

' cular scale 44.

The disk 21 is provided with a central aperture, through which passes a small .metallic tubular member or eyelet, providing a small hole through which a sight may the arm 46, if not made of transparent material as above described, is preferably cut away along a central longitudinal line,

as indicated at 49, so that the edge formed by said cutaway portion may be used as .a

sight to enable the arm to be positioned on e A the Pointer stars, as above described. shortline or marker 50 is provided on the arm 46 and is so located when the arm is extended to come opposite to the divisions on the hour scales 42 and 43. These parts are arranged to be movable in relation to the disk, substantially as described in connection with Fig.1. The eyelet 45 also retains in position a second slotted army 51, similar to the arm 46, but having a somewhat shorter slot 52, the. end of which when allow' the divisions in the circular scale 44 to be observed therethrough. Thlsarmis also provided with a central marking line '53, which will indicate the exact position ot' thearm 51 on the disk, so that it may be the arm is extended is so positioned as to it placed opposite the nearest date on the cir- The manner of using this form of my devicemay be described. as follows: The arm '51 is pulled outward as far as possible and then is rotated until the line 53 comes oppositethe date on which the observation is being made. The disk is then placed before the eyes in the same man-' ner as described in connection with the device of Fig. 1, so that the North Star will be seen through the eyelet 45, and as near as possible to the center of the eyelet. The

disk and the arm 51 are then rotatedin unison so that the center line of the arm 51' lies as near as possible in a vertical plane,

passing through the North Star and the body ot'the observer, the disk itself being held so as to lie in a plane perpendicular to the line of vision between the observer and the North Star.

a The arm 46' is then rotated-about the eyes let 45 until one or both of the two Pointer.

stars of Ursa Major lie on the line 49. The

parts are then in position for a direct reading of the hour at which the observation is taken. In the drawing, as shown in F ig. 2, the line 53 is set at a division corresponding to April 15th. *VVith the two Pointer stars in the position shown in Fig. 2, the line 50. comes between the division indicating 4.00 oclock and the next division indicating 4.15, and is practically one-third of the distance between said divisions, thus time, that is, they may be adapted for use i 7 central eyelet 33 or 45.

as instruments to determine longitude, andv when used in connection with the usual navigational tables may also be employed to determine latitude. In determining longitude, it will be apparent that when the hour of the day corresponding to the reference meridian is known by means of a chronometer and the time of the observation determined as above described, the difference bevtween these respective times will indicate the time consumed in the angular rotation of theearth beyond said reference meridian adjacent to which the deviceis designed to be used, it being understood, of course, that either one'or bothof the Pointer stars are on the reference line of the arms 30 or 46 and the Polar star is observed through the The angular rotation thus found will give the difference in longitude between the reference meridian and thepoint of observation. f

As above. stated, I am aware that modifications may be made by those skilled in the art in my device for indicating time.

I therefore do not wish to be understood as arrangement of parts herein-described, but desire protection for all forms of my device as may come within the spirit and scope of the appended claims.

It will also be apparent that the device is capable of much refinement in design and manufacture, and may be constructed as a precision instrument by the use of usual telescopic sights, vernier scales and other devices used in connection with accurate astro- 1 nomical instruments. 7

What I claim and desire to protect by Letters Patent is:

1. A steller time indicator comprising a body provided with a plane surface having a scale thereon whose divisions represent fractions of a day and provided with means i for sighting and coordinating with said scale, one of the stars being observed, means carried'on said body for sighting'and determining the radial direction of another of said stars with reference to the divisions of said scale, and means for indicating the re-' quired fixed position on which said scale is to be placed with reference to said stars.

2. A stellar time indicator comprising a plate having a central opening and a plurality of divisions at its margin representing the fractions of a day and arrangedin circular series and having indicating means for determining the required fixed position on which said scale is 'to be placed with reference to the zenith, and a member rotatable about said central opening and provided with a reference line adapted to be placed to intersect one of said stars.

V 3. A stellar time indicator comprising a disk having a central opening and a marginal scale, means forindicating the position on which a diametral line of the disk is to be placed withreference to the. zenith when an observation is being made, and a movable member adapted to rotate about said opening and having a reference line adapted to be placed so asto'intersectone' of the stars being observed and to indicate certain divi- .sions on said scale. I

4. A stellar time indicator comprising a disk having a central opening and ts margin having a scale divided into equal. II12L1I1 divisions repi'esenting'hours of the day, the marks forming such divisions being numbered consecutively from 1 to 12, there also being means for indicating the position on which a diametral line of the disk is to be placed with reference to the zenith when an observation is being made, an arm pivoted to rotate about said central opening in the disk and provided with a reference line adapted to be placed to intersect one of a plurality of stars being observed and to indi- V 'cate certain divisions on said scale. being limited to the details of form and thereon, representing two sets of twelve hours of a day each, and also having a sec- 0nd scale whose main divisions represent the twelve months of a year and whose minor divisions represent equal numbers of days in each month, said disk having acentral,

opening, through which the North Star may be observed, a pivoted member adapted to rotate about said opening in the plane of said disk, and having a reference line adapted to be placed to intersect another of the stars being observed and to indicate second member rotatable about said central opening having a reference line adapted to be set on the date of observation as provided on said disk, said line also being adapted to be directed toward the zenith in a plane substantially at right angles to a line connecting the observer with the North Star.

FREDERICK o. MEAGHAM.

the hour of observation on said disk, anda I

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