US2114501A - Electric clock - Google Patents

Description

.April 19, 1938. E. P. OSWALD ELECTRIC CLOCK Filed Feb. 13, 1937 2 Sheets-Sheet 2 6224*! Q 405%??? ZZW/ w ORNEY.

Patented Apr. 1 9 1 938 UNITED STATES ELECTRIC CLOCK Earl P. Oswald,

Oak Park, Mich.

Application February 13, 1937, Serial No. 125,546

4' Claims.

This invention relates to clocks and in .par-

ticular to electric clocks of the cyclometer type- One object of this invention is to provide a synchronous motor operated cyclometer type. electricclock.

Another object of this invention is to provide a synchronous motor operated cyclometer type electric clock having time indicating drums mounted for progressive rotation on a common axis.

Another object of this invention is to provide a synchronous motor operated cyclometer type electric clock having novel inexpensive means for progressively rotating the time indicating drums thereof.

Another object of this invention is to provide a synchronous motor operated cyclometer type electric clock having minute, ten-minute and hour time indicating drums of equal face diameter 20 and mounted for progressive rotation by novel inexpensive means on a common axis.

Another object of this invention is toprovide a synchronous motor operated cyclometer type electric clock in which the usual complicated clockwork is substantially eliminated.

Another object of this invention is to provide a synchronous motor operated cyclometer type electric clock having such simple operating mechanism as to readily fit in with high speed part production and assembly methods whereby the clock may be manufactured at a cost that will make it available to the low price field.

Other objects of the invention will become apparent by reference to the following detailed 5 description taken in connection with the accompanying drawings, in which:

Fig. l is a front elevational view of a clock mechanism embodying the invention.

Fig. 2 is a side elevational view of the embodiment oi the clock mechanism disclosed in Fig. 1 showing the notching and numbering of the minute drum.

Fig. 3 is a horizontal sectional view taken on the line 3--3 of Fig. 1.

Figs. 4 and 5 are enlarged side elevational and plan views respectively of the novel drum engaging ratchet lever employed to selectively and progressively rotate the time indicating drums.

Fig. 6 is a side eleva-tional view of the ten-minute drum. showing the notching and numbering thereof.

Fig. 7 is a side elevational view of the hour drum showing the notching and numbering thereof.

Fig. 8 is an enlarged composite more or less diagrammatic view showing the position of all the drums just after they have been moved to indicate time at an even hour.

Fig. 9 is a view in perspective showing a typical back motion spring pawl employed to prevent 5 any reverse rotation. of the time indicating drums.

Referring now to the drawings wherein like numerals refer to like and corresponding parts throughout the several views, the embodiment of the invention disclosed therein comprises, in general, a minute drum 2!], a ten-minute drum 2| and an hour drum 22 mounted for rotation independent of each other on a common shaft 23, each. of said drums being intermittently and progressively rotated by a reciprocating bifurcated ratchet lever 24 carrying a novel sliding ratchet click 25 which engages suitably disposed ratchet teeth formed on the inner periphery of the said time indicating drums 20, 2| and 22, the said ratchet lever 24 being reciprocated under the power and timing of a preferably self-starting synchronous motor 26.

The clock mechanism is supported within a suitable housing indicated by the dot and dash lines 21 in Figs. 1 and 2 on an inverted U-shaped bracket 28 through which the shaft 23 is centrally mounted through shouldered bearings 29 peened into engagement with the said bracket 23. The minute drum 20, ten-minute drum 2| and hour drum 22 journaled on the shaft 23 are assembled on the shaft 23 positioned through the bearings 29 as best shown in Fig. 3 with the reciprocating bifurcated ratchet lever 24 journaled for arcuate reciprocation on the outer periphery of the said bearings 29 and straddling 35 the ten-minute drum 2| and the U-shaped bracket 28. The said drums 20, 2| and 22 are maintained in the desired position on the shaft 23 by such suitable means as split spring clips 30 snapped over the said shaft 23 into annular 10 grooves provided in the said shaft 23 therefor.

The minute drum 20, the ten-minute drum 2| and the hour drum 22 are all of equal face diameter, the said minute drum 2!) being ten sided and numbered from 0 to: 9 consecutively as indi- 45 cated in Fig. 2, while the ten-minute and hour drums are twelve sided and are numbered 0, 1, 2, 3, 4, 5, 0, 1, 2, 3, 4, 5 and from 1 to 12 consecutively as indicated in Figs. 6 and 7 respectively. The numbering of the drums being all the same height is exposed for view through a suitable aperture 3| in the housing 21.

Each of the drums 20, 2| and 22 are formed hollow and are each supported on an integral radially disposed disc 32 having a centrally dis- 55 posed hub 33 by means of which they are journaled on the said shaft 23 as hereinbefore described.

As best illustrated in Figs. 2, 3 and 8, the minute drum 20 is internally formed on its side adjacent the ten-minute drum 2| into a ratchet wheel having nine shallow teeth 34 and one deep tooth 35 equally peripherally spaced and radially located. opposite the center of each numbered side of the said minute drum 29, said deep tooth 35 being located radially opposite the side bearing the numeral 5.

As best illustrated in Figs. 3, 6 and 8, the tenminute drum 2| is internally formed on its side adjacent the minute drum 20 into a ratchet wheel having ten shallow teeth 36 and two deep teeth 31 equally peripherally spaced and radially located opposite the center of each numbered side of the said ten-minute drum 2|, the said deep teeth 31 being each located radially opposite one of the two sides bearing the numeral 0.

As best illustrated in Figs. 3, 7 and 8, the hour drum 22 is internally formed on its side adjacent the ten-minute drum 2| into a ratchet wheel having twelve shallow teeth 38 equally peripherally spaced and radially located opposite the center of each numbered side of the said hour drum 22.

The radii from the center of the drums to the base of the notches formed by the deep tooth 35 of the minute drum 20, by the deep teeth 3'! of the ten-minte drum 2| and by all the teeth 38 of the hour drum 22 are all equal and greater than the radius from the center of the said drums to the base of any of the notches formed by any of the other teeth. The radii from the center of the minute drum 2!] to the base of the notches formed by the nine teeth 34 thereof are all equal and less than the radius from the center of any of the drums 20, 2| and 22 to any of the other teeth. The radii from the center of the ten-minute drum 2| to the base of the notches formed by the ten teeth 36 thereof are all equal and of such length as to make the bases of the notches formed by the said teeth 36 radially equidistant from the bases of the notches formed by the tooth 35 of the minute drum, teeth 31 of the ten-minute drum, teeth 38 of the hour drum and the bases of the notches formed by the teeth 34 of the minute drum.

The teeth 34, 36 and 38 are all of an equal depth and of a dimension slightly greater than the radius of the tooth engaging pins 250 of the sliding ratchet click 25 to admit of engagement thereby. The radial distance between the bases of the notches formed by the teeth 34 and 36 and the radial distance between the bases of the notches formed by the teeth 36 and 38 is slightly greater than the diameter of the said tooth engaging pins 250 of the said sliding ratchet click 25 to admit of selective engagement and progressive rotation of the drums 20, 2| and 22 thereby.

A plurality of back motion spring pawls 39 formed as best illustrated in Fig. 9 are positioned through preferably rectangular apertures 40 in the U-shaped bracket 28 in such a manner as to engage the internal ratchet wheels formed in the drums 20, 2| and 22, see Figs. 2 and 3.

Referring now to Figs. 2, 3, 4 and 5, the bifurcated ratchet lever 24 is provided with apertures 4| by means of which the said ratchet lever 24 is journaled for arcuate reciprocation around the bearings 29 which are centered in respect to the center of the drums 20, 2| and 22 as hereinbefore described. A suitably disposed clip 42 is preferably formed integral with the closed end of the bifurcated ratchet lever 24 and is provided with an aperture 43 through which a pivot pin 44 is positioned for pivotally securing the connecting lever 45 to the said bifurcated ratchet lever 24.

Arcuate reciprocation once each minute is imparted to the ratchet lever 24 by means of a positive speed synchronous motor 26 having a worm 46 on the rotating shaft 4'! thereof which engages the worm gear 48 and rotates the same once each minute. The connecting lever 45 is eccentrically pivoted on the worm gear 48 by a pivot pin 49 as best illustrated in Fig. 2. The dot and dash lines in Fig. 2 indicate the position of the connecting lever 45 and the bifurcated ratchet lever 24 at the limit of their return stroke, while the full and dotted lines in Fig. 2 indicate the position of the connecting lever 45 and the bifurcated ratchet lever 24 at the completion of their drum rotating stroke. The synchronous motor 26 preferably carries a suitable support 58 onto which the worm gear 48 is journaled by such means as a shouldered rivet 5|, the said synchronous motor 26 being supported on and secured to the upper horizontal portion of the U-shaped bracket 28.

Referring now to Figs. 4 and 5, the bifurcated ratchet lever 24 is crimped at 52 and is suitably slotted along the narrow sides 248 thereof to accommodate a bifurcated ratchet click 25 held in alignment with the narrow sides 240 of the said ratchet lever 24 by the wide sides 24| thereof and by the end 242 thereof. An additional guide and pin 53 around which a light compression spring 54 is positioned is riveted or otherwise secured protruding outward from the end 242 of the ratchet lever 24 and reciprocatingly extends through an aperture 55 provided therefor through the end 25| of the said bifurcated ratchet click 25. The said bifurcated ratchet click 25 is provided with three pins 250 suitably disposed to engage the internally formed ratchets of the time indicating drums 20, 2| and 22. The said light compression spring 54 reacts against the end 242 of the ratchet lever 24 and constantly urges the ratchet click 25 outward with the tooth engaging pins 250 thereof in contact with one or more of the internally formed ratchet wheels of the time indicating drums 20, 2| and 22 as hereinafter described.

The mechanism of the clock being thus described makes the operation of the clock obvious. Beginning at any even hour, each time the ratchet lever 24 is reciprocated once, which occurs once each minute, one tooth engaging pin 25!] engages one of the teeth 34 of the ratchet wheel formed within the minute drum 2B and advances the minute dial one numeral. After this occurs nine times, one tooth engaging pin 25!! engages the tooth 35 of the minute drum 20 and another tooth engaging pin 250 engages one of the teeth 36 of the ten-minute drum 2| whereupon the minute dial and the ten-minute dial simultaneously advance one numeral to read ten minutes after the hour.

The aforementioned operation is repeated until the clock reads fifty-nine minutes after the hour and one of the tooth engaging pins 250 engages the tooth 35 of the minute drum 20, another tooth engaging pin 250 engages one of the teeth 31 of the ten-minute drum 2|, and the third tooth engaging pin 250 engages one of the teeth 38 of the hour drum 22 at the limit of the return stroke of the ratchet lever 24 whereupon the ratchet lever 24 carrying the ratchet click 25 and the tooth engaging pins 250 advances the minute dial 20, the ten-minute dial 2!, and the hour dial 22 simultaneously one numeral each under the drum rotating stroke of the said ratchet lever 24 until the three tooth engaging pins 250 and the drums 20, 2! and, 22 are in the position or a comparable position to that indicated in Figs. 1, 2, 3 and 8, at which time an even hour is recorded through the opening 3! of the clock housing 21.

It will be noted that the relative depth of the notches of the ratchet wheels internally formed in the minute drum 20, the ten-minute drum 2| and the hour drum 22 and the various lateral alignments thereof governs whether the tooth engaging pins 250 of the sliding ratchet click 25 of the reciprocating ratchet lever 24 move one or more of the said drums 20, 2| and 22.

Although but one embodiment of the invention has been shown and described herein, it will be understood that various changes may be made in the size, shape, arrangement and details of the various parts thereof without departing from the spirit of the invention, and it is not intended to limit the scope of the invention other than by the terms of the appended claims.

I claim:

1. An electric clock mechanism comprising a positive speed synchronous motor, a minute, a ten minute and an hour time indicating drum, a common shaft, the said drums being mounted on said common shaft for rotation independent of each other, ratchet wheels formed on the inner periphery of said drums having certain of the teeth thereof at different depths with respect to the others, a ratchet lever mounted on said common shaft arcuately reciprocated once each minute by said synchronous motor, and a sliding ratchet click on said ratchet lever constantly urged radially outward into selective engagement with one or more of the said time indicating drums in accordance with the lateral and radial alignment of the notches of the ratchet wheels formed in the said drums whereupon the said drums are progressively rotated by said ratchet lever.

2. An electric clock mechanism comprising a positive speed synchronous motor, a minute, a ten minute and an hour time indicating drum all of equal face diameter, a common shaft, the said drums being mounted on said common shaft for rotation independent of each other, ratchet wheels formed on the inner periphery of said drums having certain of the teeth thereof at different depths with respect to the others, a ratchet lever mounted on said common shaft arcuately reciprocated once each minute by said synchronous motor, and a sliding ratchet click on said ratchet lever constantly urged radially outward into selective engagement with one or more of the said time indicating drums in accordance with the lateral and radial alignment of the notches of the ratchet wheels formed in the said drums whereupon the said drums are progressively rotated by said ratchet lever,

3. An electric clock mechanism comprising a positive speed synchronous motor, a minute, a ten minute and an hour time indicating drum all of equal face diameter, a common shaft, the said drums being mounted on said common shaft for rotation independent of each other, the periphery of the minute drum bearing equally spaced numerals from 0 to 9 inclusive, the periphery of the ten-minute drum bearing equally spaced numerals 0-1-2-3-4-5-0-1-2-3-4-5, and the hour drum bearing equally spaced numerals from 1 to 12 inclusive, ratchet wheels formed on the inner periphery of said drums having certain of the teeth thereof at different depths with respect to the others, a ratchet lever mounted on said common shaft arcuately reciprocated once each minute by said synchronous motor, and a sliding ratchet click on said ratchet lever constantly urged radially outward into selective engagement with one or more of the said time indicating drums in accordance with the lateral and radial alignment of the notches of the ratchet wheels formed in the said drums whereupon the said drums are progressively rotated by said ratchet lever.

4. An electric clock mechanism comprising a positive speed synchronous motor, a minute, a ten minute and an hour time indicating drum all of equal face diameter, a common shaft, the said drums being mounted on said common shaft for rotation independent of each other, the periphery of the minute drum bearing equally spaced numerals from 0 to 9 inclusive, the periphery of the ten-minute drum bearing equally spaced numerals 0-1-2-3-4-5-0-1-2-3-4-5, and the hour drum bearing equally spaced numerals from 1 to 12 inclusive, ratchet wheels formed on the inner periphery of said drums having one ratchet tooth disposed radially opposite each numeral and certain of the said teeth at different depths with respect to the others, a ratchet lever mounted on said common shaft arcuately reciprocated once each minute by said synchronous motor, and a sliding ratchet click on said ratchet lever constantly urged radially outward into selective engagement with one or more of the said time indicating drums in accordance with the lateral and radial alignment of the notches of the ratchet wheels formed in the said drums whereupon the said drums are progressively rotated by said ratchet lever.

EARL P. OSWALD.

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