US2259603A - Automatic calendar - Google Patents

Description

Oct. 21, 1941. B. s. BALINSKI 2,259,603

AUTOMATIC 'CALENDAR Filed April 18, 1959' Sheets-Sheet 1 SA a 1 JAN 3 a FRI NOW

Oct. 21, 1941.

B. s. BALINSKI AUTOMATIC CALENDAR Filed April 18, 1959 4 Sheets-Sheet 2 a gg.

Oct. 21; 1941- B. s. B ALINSKI AUTOMATIC CALENDAR Filed April 18} 1939 4 Sheets-Sheet 3 Oct. 21, 1941. B. s. BALINSKI 2,259,603

AUTOMATIC CALENDAR Filed April 18, 1939 4 Sheets-Sheet 4 Patented Oct. 21, 1941 UNITED STATESPATENT OFFICE AUTOMATIQ- CALENDAR Benjamin s. Balinski, Chicago, 111.

Application April 18, 1939, Serial No. 268,632

9 Claims. (01. 40-112) My invention relates to mechanical calen- 1 dars, and more particularly to those intended to operate over long periods, and my main object is to provide a calendar of this kind which performs its functions over a lifetime without attention or resetting as long as motive energy is supplied to it. I

A further object of the invention is to include in the novel calendar means to automatically adjust the readings for the dates of the shorter and longer months, as well as those affected by leap years.

Another object of the invention is to group the date carriers in a compact series in order to have the calender take up as little room aspossible consistent with a sufficient display of the readmgs.

An additional object of the invention is to provide a mechanism for the novel calendar which is mainly grouped at one end thereof and very compactly.

Another object of the invention is to render the calendar mechanism suitable for actuation by an ordinary time piece, such as a springwound or electric clock.

Animportant object of the invention isto provide a mechanism which is largely positivein action, contains few springs, and requires only occasional lubrication to keep in proper condition.

With the above objects in view, and any others which may suggest themselves from the descriptionto follow, a better understanding of the invention may be had by reference to the accompanying drawings, in which-- i Fig. 1 is an encased 'view of the calendar combined with a numerical clock;

Fig. 2 is a full-sized front elevation of the calendar and its mechanism;

Fig. 3 is a rear elevation;

Fig. 4 is a vertical longitudinal section through an axial plane;

Figs. 5 to are, respectively, sections taken onthe lines 5-5 to Ill-100i Fig. 2;

Fig. 11 is a fragmental repetition of the upper portion of Fig. 8, partly broken away;

Fig. 12. is a fragmental elevation of a date carrier in the normal position;

Fig. 13 is .a similar View, showing a changing position of said. carrier; 7

Fig. 14- is a mechanical detail showing a date control;

Fig. 15 is a mechanical detail showing a control for regular and leap year months;

Fig. 16 is another view showing the controls for months and date changes;

Fig. 17 is another detail showing the positions of certain controls for ordinary,shorter and leap year months;

Fig. 18 is a typical drive mechanism for the calendar; and

Fig. 19 is an elevation of a disk-type dial front for the calendar.

Primarily, the novel calendar is intended to be read horizontally. Thus, the day reading is first at the left, then the date reading, then the month, and finally the year. The readings are slightly above the center of the calendar mechanism, and the front 20- of the calendar casing 2| is formed with rectangular openings 22 to disclose a given date. Thus, the corresponding legends in Fig. 2 are alined to show this date. Since it is preferable to, havethe calendar actuated by I a clock, as previously mentioned, the casing may combine the numerical clock 23 above the cal I sired.

endar zone, as shown in Fig. 1.

The legends lofthe calendar are carried by a seriesof drums centered successively ona fixed 1 shaft25 andcarrying the legends on peripheral dialjp'ortion.

Thus, the day drum is indicated at 25,;the datedrum at 30, the month drum at 4|], the multiple-year drum at and the singleyear drum at 50. Fig. 4 shows the manner in which these drums are arranged on the shaft A collar 25a on the latter retains the assembly against sliding motion; As a modification Fig. 1.9 shows a series of disks arranged as the drums, where a fiat type of indicator is de- ,As seen in Fig. 4, the drum is formed with a hub 5| which is freely mounted on the shaft 25 and terminates at its left-hand end with a disk 52. The drum 45 also has a very short hub 45a: and a disk 4'! projected therefrom, the disks 41 and 52 being separated by aspacing collar 48.

The drum 40 is also formed with a hub 4| which is reduced as a long tube 42 to render the drum freely mounted on the shaft 25. The lefthand extremity of the tube 42 carries a large ratchet disk 43. a i I The ,drum 30. is formed with a hub 3| which is reduced to form a tube 42, which is freely mounted on the tube 42 and carries a ratchet disk 33 near its left-hand end, such end being extendedwith a radial arm 34.- The hubs 3| and 4| are spaced by a long collar 34a.

The tube32 receives a freely mounted tube 55 which carries a sector gear 51 near its left-hand end, from which projects a radial arm 58 rigidly connected to the gear 51 by a pin 59.

The drum 26 is formed with a tubular hub 2! which freely encircles the tube 56 and carries a relatively small ratchet disk 28 at its left-hand end.

It is understood that the drums turn periodically to display the successive readings thereon, and the character of the mechanism requires that some turn in opposite directions from the others. According to the markings in Fig. 2, it is evident that the day drum 2B and date drum 3!? move downwardly while the month-drum 43 and the 1 carrier to swing aside as the one for the even date year drums 45 and 50 move upwardly, arrowsindicating these movements in a rotary direction in other views. date drums 25 and 3B are instituted by the .for ward swing of the arm 58 to the extent where its companion sector gear 51 strikes a stop lugfifl carried by a cross rod 6| mounted in the lower part of the case 2|; and the movement of the month and year drums 40, 45 and 53 is induced by the return swing of the said arm 58. This arm may thus be termed as the driver for the calendar mechanism, and its companion gear is provided for receiving energy from the, clock or other external source previously mentioned, a suitable auxiliary gearing for this purpose being The movements of the day and described in a later section. The design of the calendar mechanism requires that the arm should have and accomplish a suflicient stroke for fully attaining the functions during, each of its movements, and it is therefore understood that the actuating unit will be required to impart the full or sufficient stroke to the arm in each direction. The return of the arm 58 is induced by a spring 58a leading to a'fixed rod 64.

As indicated in Figs. 2 and '7, the drum 26 is spider-like with the peripherallegend-bearing portions 29 extended side-wise like wings. order that these may come to the front indaily succession, the arm 58 is preferably actuated in a forward direction at or shortly after midnight. The disk 28 carried by the drum has the ratchet formation indicated at 29a in Fig. '7 and is formed with seven teeth. As noted in the same figure, the sector gear 51 has pivoted to it at 511; a pawl 511) which is urged against the periphery of the impelled at the same time as the day disk 28 to change the date reading on the drum 3!].

With the date drum 3!] about the same diameter as the day drum 26 in order to lend the calendar assembly uniformity and compactness, it is evident that ther will not be sufficient room on the periphery of the drum 30 to space the date carriers 39a in end-to-end succession. I therefore overlap them, as shown in Figs. 8 and 11, and cause the carrier for the previous date to move out of the way whereby to permit the carrier of the even date to fully show in the zone of display. This is done by causing the previous descends into place. The means to accomplish this is simple. Thus, the drum 30 is composite in its plies as shown in Fig. 4 in order to accommodate pairs of spring blades 39b in rotary succession and extending radially a short distance beyond the periphery of the drum. The date carriers are flat plates 39c which-according to Fig. 2are pivoted at their left-hand lower corners to the drum by means of pins 39d. These pass through square blocks 39c rigidly carried by the plates 390, the blocks occupying the places between the extended portions of th spring blades 39?). Fig. 11 shows the carrier of the previous date in a position to descend upon a stop bracket 39] shown in Figs. 2 and 8, and rigidly secured to the rod 3i The carrier rests upon this bracket, but when the drum turns to lower the carrier, it is caused by the bracket to swing to the left, as indicated in Fig. 12, opposite corners of the block 39c then spreading the spring blades 39b. The further travel of the carrier causes it to snap into position a quarter turn beyond its original place and remain fixed by virtue of the pressure of the spring blades as shown in Figs. 13 and 2. Thus, the previous date reading is moved independently to a concealed position on each movement of the drum 30, so as to leave the even date reading in full view at the place of display. The next move of the drum causes the swung carrier to meet the upper end of a stop bracket 39g carried by the ratchet disk 28 by a spring 51d. Therefore, every forward stroke of the arm 58'that is, .in the direction of the arrow in Fig. '7-will be calculated to rotat the disk 28 a sufficient distance to change the day reading in front. The disk 28 is of course controlled by a check pawl 510 which is pivoted on a rod 62 located in the rear of the casing. The spring 63 for the check pawl 510 is anchored on another rod to the rear of the rod 62 and numbered 64. The day readings are thus advanced and repeated without incident.

It has been mentioned that the drum 30 is directly connected with a ratchet disk 33, andthe latter is therefore intended to take a partial turn each day, in the manner of the day ratchet disk 28; to change the date. The disk 33 is therefore formed with 3! peripheral teeth and is actuated by a large pawl 35. which is pivoted at its base on aside pin 36 carried by the arm 58, and is drawn toward the periphery of the disk 33 by aspring 31 secured between the pawl and the arm. These parts arejshown in Fig. 6, and it is noted that the disk 33 also has a check pawl 38 underneath, the same being mounted on the rod 6| and with its spring 39 anchored on a pin fila. It follows, therefore, that the disk 33 would be Figs. 6 and 16.

rod 6|, so that the carrier is in this manner forced to swing back-in clock-wise directionto its original position on the drum, this position, however, being below the display zone and maintaining the carrier in the concealed position.

It is recalled that the ratchet disk 43 is directly connected to the month drum 4!]. The teeth of the disk 43 are of course twelve in number, to agree with the peripheral portions 46 of the drum, which carry the readings. As was previously mentioned; the month drum is intended to rotate in the opposite direction from the day and date drums, and it follows, therefore, that the teeth 45a of the disk 43 are pointed in a reverse direction, as shown in Fig. 5. In order that the disk 43 may be drawn the distance of a tooth each month, a hook pawl 46 is also mounted on the side pin 36 of the arm 58 and is intended to fall in front of a tooth 45a when the arm 58 has advanced the date disk 33 by means of the pawl 35 to a point where the reading is th first of the month. The peripheral notch in the date disk 33 in this instance is deeper than the others, as indicated at 33a in The pawl 35 has thus taken a deeper fall. The head of the hook pawl 46 carries a side pin 43a below a finger 35a forwardly projected from the pawl 35, as shown in Fig. 6. It follows, therefore, that the fall of the pawl posit the same in front of the proper tooth of anemone? thermonthadisk: 43; so; that ithereturnistroke. ofthe arm 58 draws' this'd-isk throughras partial turn: in @the direction, indicated: by'the'rarrowinn Fi'g-.. 5 or 16-, raising the next; month :reading; to the display: zone. Th8h00k: pawl 46 isnormally: 5 urged away from the disk 43 by auspring 46z di-- rected' from the side pin 36;- as'shown-in Figs. 6- and:16;- As noted in Fig. .5, the month' 'disk 43: receives a check pawl 46bunderneath, such: pawl being. pivoted 'on therod-62: and urged. upwardly;-

by" a spring 460 which bears against-the'rod' 64: When the'hook pawl 45? draws. on the month disk- 43'-as: farback as thearm 58 is' calculated to recede; it might; be assumed that the spring; 462 'willJautom-atically, urgerthe hook: pawl to dis l5 en'gagethe disk at the end of the stroke. Yet; it" is possible that-this will not occur because-of: the; engaging hold of the pawl upon the dish-even: at-the endfofrthestroke: Ihave thereforeformed thechecktpaWl 46b forthe disk43 with a; round- 20 ed cam point 46d whosezinfluence as'it snaps= into-the" proper: tooth notch-of thedisk isttoveryslightly urge the disk ahead, that is; slight= lybeyond the point towhich it wastdrawn, This) action will automatically-free-the-hook ofthe-: pawl :46; so that ithessamayields to. the'influence of the spring-462m swing. away; from theperiphery of the-disk43-..

It Will-be. recalled thatithe ratchet disk 52is carriedb ythe single year drumifl; and the disk is cut with asmanyteeth as there arerperipheral reading. divisions 50a. on the said rdrum; namely" ten, readingfrom '1' to .0. When the month; drum 40 has gone around once, it acts to shift theyear drum 50 a sufficient distance to display thernext figure. Accordingly, the month drum carries a. pin 53- which is adapted to meet a side'lug-54 when the. drum 40a rotates in the: directionindicated by theiarrow inrFig. 9. 'Ihe=lug54 is, carried. by a: bracket 55 pivoted'orr the.'rod;62 at its" lower end. To the upper: end: of the bracket' 55'ispivoted 'a lever 5510, this lever-extending below the pivot 51k to: be connected with its'lowerwend to'a stationary arm 65 by--a draw-spring 66; The arms 55 is.fast on thB1I0d 62 and carriesa lateral stop 45.,

pin filter-the bracket 55.- Theuppe-r'portion =01 the'leve-r 55kcarriesea -crossmin 68; one ofwhose' sections-seatsin one-of the.-tooth notches 52a. of the ratchet disk 52'." Thus; as the side. pin 53 of themonth. drum 'continuesttor impinge onthe- The 'movement just described-serves to rotate the yeardrum 50+ one-revolution everyten years, and this 'movement'is"employed. to act on the multipleyear drum 45 to give! the same a partial turn to' secure the-even. ten-year numbers, such. as Ill; 20,- 30; etc. Accordingly, one toothnotch. 52b of the ratchet disk 52 is deeper'than-the other nine; as-shown in Fig; 9e Ordinarily, the motions of the-lever 557cand, cross-pin 68' do not affect. the ratchet' disk 41, as; the latter is: of somewhat. smaller diameter: thanthe disk:- 52; so. that the correspondingportion; of the-pin 58 simply" rides above the periphery-of thedisk4'1;

However; when! the 10-year change is: to be made;

the cross-pin 68 falls-into thedeep notch 52!) and at'the same time into :thetcompanion notch of" 70:

01- also :1 carried: by

year: 99,.'whi'ch2is over a: period solong; as tobe well :beyond the :average span of life.

It. is .evidentzxthat alcalendar of the type herein'adescribed must provide adjusting means for months-ewhichr have less than 31- days. Thus, April, June; Septemberand November have 30 days; leapt-yearv February has 29 days and ordinary -February '28 days. This circumstance: affeats-the: date-drum; since the date must change to-the: 1st of" the next month before the current monthisallowed'to run 31' days. presentv calendar mechanism I cause thedatedrum'to be drawn through "twosteps when the month ends with'.the-30th day, soithat the next date in: view' will. be' the" 1st of the following month. Likewise, I cause the drum to be drawn throughithree' steps at the; end. of a:29-day month and: thrcugh four' steps at'the end of-a 28-day -fronta1point. The-pawl 35 is sufficiently wide: to

travel overboth the date'disk 33 and the cam 10a, as appears in Fig. 3; Ordinarily, one tooth of the date: disk occurs-.infront of the cam fall 10b, so that the advance-of the pawl 35 a short distance farthersecuresthe partial turn of the disk throughtone date; It will nowbe apparentfrom Fig. 14 on l6xthat-if the sector plate 10 isswung a short distance-in a clock-wise direction, another datewtooth will be exposed frontally of the cam fall 10b, so that-.onthe advancethe pawl 35 will drop onto-the date dish a tooth earlier and so servejto push the 'disk over the distance of two teeth before the pawl reachesthe endof its advance. It follows, then, that the backing of the cam 1|] still farther will accomplish-a longerdate:

mentioned is always present by the pull of a spring" upon the sector plate toward a fixed bracket 12 carried by the side pin 6la, as seen in Fig: 6. In this manner the sector plate is'drawn to a back limit" formed by a detent 13 which engages a notch I4 near the lower end of the cam 10a, the detent'beinggpivoted on the rod 62; as indicated in Figs: 14' and 16;

With thesector cam Illa described as a control for the engaging function of the pawl 35, it is necessary to determine how the various positions of the cam arefixed by the exceptional month ,1 values previously mentioned, that is, months having' 30, days, .29 days and 28 days. These values are-representedby-a set of angle cams 15 carried by the, month: disk 43 at points near its periphe-ry, as-clearly shown in- Fig; 5. Each angle cam is pivoted-on a pin 16 carried by the disk; and

the tail 15a-of 'each'cam isurged bya wire spring. "in. clock-wise direction to abut-a stop. pin 18, the spring extending from a pin 19 on the disk. Considering the direction of rotation of the disk. 43, it is'seen" that each angle cam 15 and its tail 15arecede inclinedly from the pivot point".

The angle-cams 15 are five in number, four representing the 30-day months and the fifth the 29-day and;the.28'-day Februaries.- Behind the. 10-year; drunr 45; the calendar is ,capable of displaying; readings; from"the':yeadr01 to the- In the the series of angle cams is a curved arm 88 which is pivoted on'the rod 62 jointly with the detent 13, by means of a common hub 88a, indicated in Figs. 3, 5 and 14. Below the pivot 62 the arm 88 is drawn by a spring 8| to the cross-rod 64. The upper portion of the arm 80 is deflected forwardly to form a finger 801) which is directly'in the path of each angle cam when the disk 43 takes a rotary movement as shown in Fig. 5. Thus, a given angle cam changes from the position denoted by full lines in Fig.1? to either of the three positions indicated by dotted lines in the same figure. The four angle cams at the lower right and upper left in Fig. 5 represent the -day months, and it may be assumed that these angle cams occur in the uppermost dotted line position in Fig. 17 as each in turn gets under the finger 80b.

It was stated in an early section that'the tube 32 extended from the date drum 30 carries a radial arm 34, and it maynow be specified that this arm is within the circle of the angle cams 15. The arm is tapered to a rounded point, as indicated at 3411, which travels close to the free ends of the angle cam tails 15a as the date' drum pin 8! strikes the inner side of the angle cam tail 15a. This means that the sector cam 18a has moved over through the space of an extra tooth on the date disk 33, permitting the pawl to engage the said disk one tooth earlier on the advance and move the disk over through two dates. The arm 34 is so positioned in relation to the array of dates on the drum 30 that these two dates are the 30th and 31st. Consequently, for a 30-day month the 30th and 31st date readings are moved over together when the first reading of the next month is to be exposed.

The remaining angle cam 'I5at the top right in Fig. 5-is intended to set the date drum for the 29-day and 28-day Februaries. The action in reference to this angle cam is precisely the same as in the previous instances, except that this cam occurs in the middle dotted-line position of Fig. 17 when the 29-day month ends and in the bottom dotted line position when the 28- day month ends. These positions indicate that the tails of the respective angle cams are one and two steps farther from the approachof the side pin 8| shown in Fig. 14, and that the sector plate 10 will swing correspondingly farther on its release by the detent l3, offering increasing exposures of the periphery of the date disk 33 for the progressively earlier engagement of the pawl 35. It follows, therefore, that the 29th, 30th and 31st date reading s'will be moved over in unison at the end of a leap year February, and that the 28th, 29th, 30th and 31st date readings will be similarly moved at the end of an ordinary February.

The February angle cam is not directly secured to the disk 43, but is pivoted on a pin 16a which passes through a slot 43a in the disk 43 and is carried by the outer portion of an arm 82 pivoted on the main shaft 25 along the outer side of the disk 43, as indicated in Figs. 5 and 15. The disk 43 has an outwardly projecting fixed spindle 83 on which is journaled an integralv assembly of a disk' cam 84 and a spur gear 85. The cam 84 is in the plane of the arm 82 and ordinarily presents a circular periphery to the latter as indicated in Fig. 5, the arm being maintained as a follower against the cam periphery by a spring 86 (see Fig. 5) directed to a pin 81 carried by the plate 43. The cam has a fiat peripheral portion 84a, and Fig. 15 shows the position of the arm 82 when it is opposite such portion. In such event, the related angle cam 15 is with its pivot in the upper part of the slot 43a; and when the cam 84 is in the'position of Fig. 5, the angle cam is at the bottom of the slot. These positions correspond with the middle and lower dotted line positions-of the angle cam in Fig. 17, the basic functions of these having been previously described. I

The stationary shaft 25 carries a fixed spur pinion 88 in mesh with the gear 85. Considering that the month disk 43 undergoes one revolution a year, a ratio of 4 to 1 between the gear 85 and the pinion 88 will impart one revolution to the gear 85 every four years. The cam 84 is so arranged that its circular portion is opposite the arm 82 during three ordinary years and the fiat peripheral portion 84a is so located during the fourth or leap year. Consequently, during the leap year the corresponding angle cam 15 will be at the height of the middle dotted illustration in Fig. 1'7 and change the end of the February reading on the 29th, whereas during the other three years the angle cam will be in the position of the lowermost dotted illustration in the same figure and change the said reading on the 28th.

It will be noted that the cam fall 70b is as deep as the special notch 33a of the date disk 33, the reason for this being to allow clearance for the entry of the pawl 35' into the notch 33a. This is apparent in Fig, 16, and it will be noted that to the left of the fall 1817 the sector plate 10 has a ledge 10c followed, by a stem 10d. The ledge is in front of the pawl 35 and even with the left-hand wall of the notch 33a when the parts are positioned as in Fig. 16 for the change of the month. As for the stem 10d, it is ordinarily in spaced relation to the advanced position of the pawl 35. Thus, when the dates of a 31- day month are consecutively shifted, the pawl 35 rides'at the level of the regular tooth notches of the disk33. Now, when the pawl has advanced at a time where the detent 13 is withdrawn as previously described to release the sector plate 10 to the backing pull of the spring H, the stem 10d of the sector plate immediately moves to meet the front of the pawl 35, and the retraction of the latter checks the sector plate from a too rapid or noisy return. On the advance of the pawl the deep notch 33a gives it access to the ledge 700 of the sector plate to re-set the pawl in the foremost position.

The auxiliary gearing for driving the sector gear 51 will now be described. Fig. 18 shows an alarm or other special wheel 88a of the clock or other time device which turns one revolution at a given clock time, which is of course every twelve hours. The wheel 88a carries a swiveled radius block 83 which is slidable in a slot 90 in one arm 9| of'a bell crank 92 which is pivoted at the angle on a stationary shaft 93. A pawl 94 extends pivotally from the other arm of the bell crank to the peripheries of a single-tooth ratchet gear sector 95 and a multiple-tooth ratchet disk 96, these units being journaled alongside each other on a stationary shaft 91. The gear sector ,p'awl movable daily'relative to said .teeth to nor- 95, is operatively connected through an intermediate pinion 98 to the sector gear 51. It is the'function of the special wheel 88a to swing the bell crank 92 a given distance in the counterclockwise direction and back with each revolution, this having the -efiectthrough the pawl 94-to turn the disk 96 counter-clockwise the distance of one tooth, the disk remaining or being suitably held still on the return of the pawl. The tooth of the gear sector 95 receives the pawl at the same time when the sector gear 51 is in the idle or rear position, so that this gear is advanced through its stroke by the action of the pawl 94. The time at which the special wheel. 88a induces the above movements is set to occur shortly after midnight, or at any time during the night, to procure the necessary calendar advance for the next day. As a matter of example, the action may occur at 12:01 a. m. Now, when the clock wheel 88a is again actuated at 12:01 p. m.its impulse to the calendar must not occur, asthat would advance the calendar againat noon. Alternating teeth of the ratchet disk 96 therefore occur at a greater radius than the gear sector tooth, so that when the disk is again turned the pawl 94 will be higher and out of reach ofthe gear sector tooth. The above mechanism has been described as a preferable one, although any other which serves the ultimate purpose may-be employed. It is noted that the pawl 94 could out of the way or in a manner to be designed as a separate or auxiliary unit. It is also possible to actuate the calendar mechanism from a remote source, that is, Where the clock or timer is elsewhere and transmits its impulse electrically 'to a magnet or solenoid whose armature is the actuator. It is feasible in this manner to control a plurality of calendars in different rooms,

'oflices or parts of a building from a centralized source, providing an automatic calendar service.

It will be evident from the above description that a calendar is provided which is fully automatic over the span of a lifetime. With electric current available in all communities in one form or another, the supply of the necessary energy is easily available for the mechanism which operates the calendar, whether the same is a clock incorporated in the calendar housing or simply an electric timing device auxiliary to the calendar mechanism. Considering its functions, the mechanism is quite simple and of a nature to be compactly designed so that it may occupy a minimum of room. Further, parts of the mechanism have a limited operation but once a day and other parts more seldom, so that wear of the mechanism is so slight as to be negligible. Further, it is a simple matter to approach the drums from the rear, to re-set them if necessary, by withdrawing the controls thereof momentarily. Finally, it will be obvious that the calendar can be built by modern manufacturing methods to sell at a reasonable figure.

While I have described the novel calendar along specific lines, various minor changes and refinements may be made therein without departing from its principle, and I consider all such changes and refinements as coming within the scope and spirit of the appended claims.

I claim:

1. In an automatic calendar, a date unit having 31 teeth representative of 31-day months, a

mally advance'xthe unit a step each day, a month unit; means actuated on the last day-of-themonth 'by thedateunit to advance the month unit a step in the rotation of a calendar month,

and -a control governed by the positions of the month unitto accelerate the date unit at the end I of months of less than 31 days a number of steps equal to the difference of days in such months, dates-of-the-month and months-of-the-year 'dials carried by said date and month units and disposing readingsin rotation in regionsof display, said pawl having an advancing movement over several teeth, said control including a cam alongside the teeth and of a height to normally withhold the pawl from engaging the teeth until the final portion of its advance where the pawl moves the date unit one tooth, means to retain the-cam in its normalposition, means to retract the cam when theretaining means is released,

elements carried by the month unit for the release of the retaining means at points corresponding to the display positions of months less than 31 days, and an-actuator-carried by the date unit and effective on said elements when the last daysof such-months are on display to release the retaining means and allow the cam to be retracted a distance exposing to the pawl a number of saidteethequal to the difference of days in the shorter months from the -31 day months.

2. In an automatic calendar, a date unit having 31 teeth representative of 31-day months, a pawl -movable-daily relative to said teeth to normally teeth,'said control including a-cam alongside'the teethand of a height'to normallywithhold the pawl from engaging the-teeth until the final portion of itsadvance where the pawl moves the date unit one tooth, means to'retain the cam in its normal position, means to retract .the cam when the retaining means is released, .elements carried=by the month unit forthe release of the retaining means at points corresponding to the display positions of months less than 31 days, an actuator carried by the date unit, and a stop carried by the cam and effective when meeting the releasing one of said elements to determine the extent to which the cam becomes retracted.

3. In an automatic calendar, a date unit having 31 teeth representative of 31-day months, a pawl movable daily relative to said teeth to normally advance the unit a step each day, a month unit, means actuated on the last day-of-the-month by the date unit to advance the month unit a step in the rotation of a calendar month, and a control governed by the positions of the month unit to accelerate the date unit at the end of months of less than 31 days a number of steps equal to the difference of days in such months, dates-of-the-month and months-of-the-year dials carried by said date and month units and disposing readings in rotation in regions of display, said pawl having an advancing movement over several teeth, said control including a cam alongside the teeth and of a height 'to normally withhold the pawl from engaging the teeth until the final portion of its advance where the pawl moves the date unit one tooth, means to retain than 31 days, an actuator carried by the date unit, means carried bythe month unit independently positioning the one of said elements relating to February dates, and a connection effective by the movement of the month unit to shift said element to vary the last-day display of February dates from the regular 28th to the leap-year 29th.

4. In a calendar mechanism, a ratchet datedisk effective on rotation to display readings of dates of the month, a pawl reciprocable over the disk periphery and effective on the advance to move the disk for daily displays to the end of the month, a companion-reverse-ratchet monthdisk effective on step-by-step rotation to display readings of months, of, the year, the first-day tooth of the date-disk defining a deep notch, a second pawl reciprocable over the month disk periphery and effective on retraction to move such disk in said rotation, and means between the pawls to lower the second one into engagement with the month-disk when the first pawl falls into said notch.

5. In a calendar mechanism, a date disk having 31 teeth representative of 31-day months, a pawl adapted to be advanced daily relative to said teeth to normally turn the disk a step each day, a month disk, means actuated on the last day-ofthe-month by the date disk to advance the month disk a step in the rotation of a calendar month, a cam alongside the periphery of the date disk and barring said pawl from engaging the date disk before becoming efiective for said step, means influencing the cam to move in a direction opposite to the rotation of the date disk, a detent checking the movement of the cam in said direction, an extension of the detent alongside the month disk, rockable units carried by the latter at points corresponding to months shorter than 31 days and in the path of said extension to be deflected thereby when intercepted, an arm carried by the date disk and, eifective to rock a deflected one of said units at a point consistent with the position of the pawl for the premature engagement with the date disk to advance it through the non-existent dates of the particular shorter months, the rocking of said deflected unit crowding the extension to disengage the detent from the cam and permit the same to move, and a projection carried by the cam to meet said unit and stop the cam at a point to clear the pawl for said premature engagement.

6. The structure of claim 5, a false support for the February unit relative to the month disk, and a second cam geared to the latter to rotate once in four years, the support being influenced by said second cam at the end of a leap-year February to move the related unit forward and aifect said pawl accordingly.

7. The structure of claim 5, a follower arm pivoted co-axially with the month disk, a stationary axle for the latter, a pinion fast on the axle, a planetary gear carried by the month disk in mesh with the pinion at a 4 to 1 ratio, and a cam carried by the gear with a dwell to maintain the related unit in a position to affect said pawl at the end of a regular February and with a fall to move such unit forward at the end of a leap-year February and affect the pawl accordingly;

8. In a calendar mechanism, a date drum having peripheral sections for step-by-step daily display, said sections overlapping in rotary sequence to permit as many as 31 sections to be grouped compactly, and means operative when a given date section is on display to draw aside the next overlapping section, whereby to leave the displayed one in full view, the sections being pivoted at one of their corners to the drum, and said means comprising an abutment in the motive path of the sections.

9. In a calendar mechanism, a date drum having peripheral sections for step-by-step daily display, said sections overlapping in rotary sequence to permit as many as 31 sections to be grouped compactly, and means operative when a given date section is on display to draw aside the next overlapping section, whereby to leave the displayed one in full view, and other means to replace the section drawn aside into the series at a point beyond the zone of display, the sections being pivoted at one of their corners to the drum, and said other means being an abutment in the motive path of the moved section and efiective to swing it back to normal position on the movement of the drum.

BENJAMIN S. BALINSKI.

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