US2061665A

US2061665A - Horological device

Info

Publication number: US2061665A
Application number: US48949A
Authority: US
Inventors: Machek Johan
Original assignee: Individual
Current assignee: Individual
Priority date: 1935-11-09
Filing date: 1935-11-09
Publication date: 1936-11-24
Anticipated expiration: 1953-11-24

Description

Nov. 24, 1936. J, MACHEK 2,061,665

HOROLOGICAL DEVI CE Filed Nov. 9, 1935 4 Sheets-Sheet 1 Fel 4 Sheets-Sheet 2 IJ. MACHEN HOROLOGICAL DEVICE Filed Nov. 9, 1935 M' www Nov.. 24, 1936..

J. MACHEK 2,061,665

HOROLOGICAL DEVI CE Filed Nov. 9, 1955 4 Sheets-Sheet 4 Patented Nov. 24, 1936 UNITED TATES ,esta

PATENT @FFME 7 Claims.

jectionable in that they did not automatically compensate or correct for leap year and for i() the variation in the number of days in the respective months of the year. It was therefore necessary to occasionally make this correction manually, in order that the date indicated would vbe correct.

15 Having in mind the disadvantages and objections to the prior art devices, the present invention contemplates an improved calendar mechanism wherein the current day of the week, day of the month and the month of 2O. the year Will be automatically disclosed, and in which the mechanism is so constructed that the date denoting indicia will be automatically changed in such a manner as to compensate for leap year and the variations in the number of days in the respective calendar months.

A further object of the invention is to provide a hero-logical device having indicating hands and a dial, similar to those of a conventional clock, which is adapted to automatically indi- 30 cate the current date.

A further object is to provide a horological device of the hereindescribed type, wherein the date indicating in-dicia are automatically changed with a'jump or snap action from one indicium to 35 another.

A further object is to provide in a date indin eating device improved automatic mechanism for actuating and controlling the change of the date indicating indicia so as to correctly denote the 40 current date at all times.

A still further object of the invention is toI provide novel means for compensating for leap year and the variations in the number of days constituting the respective calendar months.

45 It is also an object to provide a date indicating mechanism of such construction that it may be utilized as an attachment for a time indicating device, such as a clock, and when so attached its operation will be controlled by the 50 time keeping device.

In accordance with the general features of the present invention it is proposed to provide a lloro-logical device having two adjacently disposed dials. One of these dials is prov ided with 55 conventional clock time indicating indicia and is traversed by the conventional hour and minute hands as in the ordinary clock, for indicating the time of the day. The other dial is provided with two concentric circular scales which are respectively traversed by hands similar to the 5 hour and minute hands of the ordinary clock. The outermost of these scales has thirty-one equally spaced graduations bearing numerals from one to thirty-one, inclusive, for indicating the days of the month; while the innermost l0 scale has twelve equally spaced graduations bearn ing numerals from one to twelve, inclusive, for indicating the months of the year.

Corresponding to the conventional second hand of a clock, the latter dial also is provided with a similar hand, this hand traversing a circular scale having seven equally spaced graduations bearing numerals from one to seven, inclusive, for indicating the days of the week. While, in the disclosed embodiment of the invention, numerals have been utilized to indicate the days of the week and the respective months, it is conteurplated that letters or other suitable indicia may be utilized, if desired.

The clock and date indicating portions of the device are respectively provided with their own individual operating mechanisms, and these two mechanisms are interconnected by means of a link so that the operating mechanism of the clock will control, through suitable tripping means, the operation of the date indicating mechanism at predetermined time intervals, in this case every twenty-four hours.

An additional feature of the invention resides in an improved mechanism for moving an indieating hand with a snap action from one scale indicium to another. For this purpose, a pair of gears is adjacently mounted for rotation on a common arbor. These gears are interlocked by means of loosely meshing alternately disposed projections which permit limited relative rotational movement of the gears. Moreover, these gears are flexibly interconnected by means of a spring so that one of these gears may be slowly advanced While the other is held against movement. This action tensions the spring and stores up energy which is available, upon the release of the previously held gear, to advance the same with a snap action through the limited distance relative to the gear that was rst moved. By mounting an indicating hand for movement with the spring actuated gear, this hand will likewise be moved with a snap action. The gears are latched, advanced and released by means of suitable pawls as will hereinafter be more specical- 1y described in detail.

Other objects and features of the invention will more fully appear from the following detail description taken in connection with the accompanying drawings which illustrate a single embodiment thereof, and in which:

Figure l is an elevational view of a horological device embodying the features of the present invention;

Figure 2 is a side View of the mechanism for actuating the hands of the date indicating portion of the device;

Figure 3 is a vertical sectional view of the mechanism taken substantially on line III-III of Figure 2;

Figure 4 is a fragmentary sectional view showing details of the instrumentalities of the day of week mechanism;

Figure 5 is an elevational view of the mechanism showing the instrumentalities for the month of year indication;

Figure 6 is an enlarged fragmentary sectional view showing details of certain parts of the same, taken substantially on line VI-VI of Figure 2;

Figure 7 is an enlarged sectional View taken substantially on line VII-VII of Figure 6, and having cut away portions to show details of construction;

Figures 8 and 9 are enlarged fragmentary plan Views partly in section and having cut away portions to illustrate the escapement releasing and latching mechanism; and

Figures 10, 11, 12, and 13 are views diagrammatically illustrating the operation of the master gear for automatically compensating for leap year and a variable number of days in the calendar months.

As shown on the drawings:

Figure 1 of the drawings discloses a horological device, generally indicated by the number I5, which embodies a time indicating dial I6 and a date indicating dial I1. The dial I6 has associated therewith the conventional hour hand i8 and minute hand I9 which are driven by means of a clock mechanism of the conventional type.

The dial I1 at its peripheral margin is provided with two concentrically disposed scales 20 and 2 I. The inner of these scales contains indicia such as numerals from l to l2 inclusive, these numerals being equally spaced circumferentially of the dial and cooperating with a hand 22 to indicate the respective months of a` year, the outermost dial 2l is composed of equally spaced and circumferentially extending numerals from 1 to 31 inclusive which cooperate with an indicating hand 23 to indicate the days of a month. Disposed above the axis of rotation of the

hands

22 and 23 is a small hand 24 which traverses a relatively small circular scale 25 bearing indicia from 1 to '1 inclusive for indicating the respective days of the week. The

hands

22, 23, and 24 are driven by means of an operating mechanism which is, except for features of control to be later explained, separate and apart from the clock mechanism.

It is therefore evident that an observer may by viewing the two dials of the device easily ascertain the month of the year, the day of the month, the day of the week and the time of the day, The indications on the" date dial are automatically changed and the mechanism is so constructed as to automatically compensate for leap year and for the variable number of days of the month. Although numerals have been utilized in the disclosed embodiment of the invention, it will be readily apparent that any other suitable indicia may be used without departing from the concepts of the present invention.

The mechanism for actuating the

hands

22, 23, and 2&1 is operatively associated with and the Various instrumentalities thereof are mounted on spaced front and

back plates

26 and 21 which are secured together by spacer posts 28 to form a frame structure.

The driving means in this case is a spring motor which is of the conventional type comprising a spring drum 29 which houses a spring (not shown), one end of this spring being connected to the drum and the other end connected to a shaft 30. Associated with the winding drum 29 for unitary movement is a driving gear 3|. The drum and gear are rotatable relative to the shaft.

The shaft 33 is rotatably mounted in the

plate members

26 and 21 and terminates at one end in a key stem 32 adapted to receive a winding key. This shaft also carries a ratchet wheel 33 which permits rotation of the shaft in a direction to wind the driving spring, and is held against reverse movement by a check pawl 34 which is normally actuated by means of a spring 35 into engagement with the teeth of the ratchet wheel.

The driving gear 3I meshes with a pinion 36 which is rotatable with a shaft 31 having its ends rotatably mounted in the

plate members

26 and 21.

Rotation of shaft 31 under the impulse of the driving motor is controlled by an escapement of the anchor type. The shaft 31 carries an escapement wheel 3S having thirty-one teeth Advancement of the escapement wheel is controlled by

pallets

39 and 40 which are disposed on opposite sides of a pivotal support 4I of a pallet supporting arm 42.

The pallets 39 and 4Q are actuated once every 24 hours to normally advance the escapement wheel one tooth. This is accomplished by means of a release and latch mechanism which is controlled from the mechanism of the adjacent clock or time indicating element of the device comprising this invention.

For this purpose there is provided in connection with the clock mechanism a rotatable disc or gear 43, as shown in Figure 4, this gear being arranged to make one complete revolution in twenty-four hours. The gear 43 carries a pin 44 which is. spaced outwardly of the center of rotation of the gear and extends into a slot 45 of a reciprocable lever 46. This lever is pivotally connected as shown at 41 to the outer end of a main arm 48 which is xedly secured at its other end to a rotatably mounted shaft 49 so that once every twenty-four hours the shaft 49 will be rotated a limited distance in one direction and then in the opposite direction.

There is also mounted on the shaft 49 for rota* tion therewith a heart-shaped jaw supporting member 50 which supports a pair of jaws 5I and 52. These jaws, which are of different lengths, are spaced apart and pivotally mounted on the supporting member by

pivot pins

52 and 53 respectively. A tension spring 54 interconnects the jaws 5I and 52 and acts to pull them towards each other until restrained by stop pins 55 and 56 respectively engaging associated abutment lugs on the jaw supporting member. These jaws are free to be moved apart relative to each other against the tension of spring 54.

The escapement wheel is normally latched against movement by the engagement of an abutment block 51 on the pallet supportinglarm with the outer end of the longer of the jaws as shown in Figure 3.

It will be observed that as the disc 43 continues Y to move, the pin and slotted link connection will cause the arm 48 to slowly move in a clockwise direction, whereupon the jaw 5| will disengage the block 51, and since the jaws are also being moved in a clockwise direction, the block 51 will be moved into engagement with the outer end of the shorter jaw 52.

As the arm 48 begins to move in the opposite direction or counter-clockwise, the block 51 will Aengage the overlapping end of the jaw 5| and gradually cause it to be forced away from its normal positie-n until a point is reached wherein the block may move between the jaws 5| vand 52. This action permits the pallets to operate and advance the escapement wheel one tooth. During this operation the block 51 will be moved outwardly from between the jaws 5| and 52, and when this happens, the spring 54 which has been tensioned will again pull the jaws towards each other and the block 51 will be latched against further movement in a direction towards the jaws, until such time as the arm 48 is again shifted in a clockwise and then counter-clockwise direction.

"Day of week mechanism The day of the week is indicated by hand 24 which is moved from one indicia to the next with a snap action. Movement of this han-d is accomplished once every twenty-four hours by the mechanism as shown in Figure 4. A pair of gears 58 and 59 are mounted for coaxial rotation in the -end of a supporting block 68a, each gear having angularly disposed teeth, `in this case seven teeth each, which extend in opposite directions. The gears 58 and 59 are loosely coupled in the same manner as the gears for actuating the day of the month indicating hand 22, which will subsequently be explained in detail. In general, the gears 58 and 59 have loosely meshing and alternating projections which permit limited movement of one gear relative to the other. The .gears are also connected to the respective ends of a coiled spring so that if one gear is held stationary while the other is rotated a limited amount, the rst gear when released will move with a snap action through the distance the other gear has been moved. More speciiically, the arrangement for moving these gears comprises a hook pawl 68 having one end pivoted at 6| to the arm 48. This pawl is normally biased against rotational movement in a counter-clockwise direction by means of a spring 62, this spring tending to maintain an abutment 63 on the pawl in engagement with a stop pin 84 on the arm 48. The hook end of the pawl engages the teeth of gear 59, and since this gear is provided with seven teeth, it will be apparent that each time the arm 48 is moved, this movement taking place once every 24 hours, the gear 59 will be shifted one tooth. This action energizes the spring connecting the gears 58 and 59, and gear 59 is retained in the advanced position by means of a slip pawl 65 which is pivotally supported in the block 68 and has its gear engaging end biased against movement away from the gear by an expansion spring 86. The gear 58 is latched against rotational movement in a counter-clockwise direction as viewed in Figure 4, by means of a latching lever 61 having a pin 68 which is disposed between the teeth of the gear when the latching lever is in latching position. Movement of the latching lever 61 about its pivot 68 in a direction to move the latch pin 68 to unlatched position, is opposed by a spring having its outer end anchored to the plate 26 as shown at 1|.

Since the movement of arm 48 also releases the escapement mechanism once every twenty-four hours, advantage may be taken of the movement of the pallet supporting arm 42 to move the latching arm 61 to unlatched position. This is accomplished by providing a pin 12 on the latching arm 61, which is engaged by the pallet supporting arm, when the pallet supporting arm is moved in a counter-clockwise direction. This movement of the arm 42 will shift the latching arm 61 against the force of spring 10 and move the latch pin 68 from between the teeth of gear 58, thereby letting this gear'move -with a snap action to advance the hand 24 to the next succeeding day of the week indicating numeral.

The gear 58 is secured to a shaft 13 whichis rotatably mounted in the plate 26 and has the hand 24 xedly secured to the outer end thereof.

Month of year mechanism Due to the similarity in the manner of operation of the hand 22 for indicating the respective days of the month, this mechanism will now be described.

As before stated, the escapement wheel 38 is provided with thirty-one teeth corresponding to a month having a maximum number of days. By means of a correcting mechanism for compensating for months having less than thirty-one days, the escapement wheel will be moved through one complete revolution each month, regardless of the number of days in the month. Correspondingly, the shaft 31 will also make one complete revolution each month.

As in the case of the gears 58 and 59 which are utilized in operating the day of the week indicating hand 24, the hand 22 is actuated in a similar manner by gears 14 and 15. The details of interconnecting these gears are clearly shown in Figures 6 and '7.

One end of shaft 31 extends outwardly of plate 26 and has rotatably mounted thereon a sleeve 16 which at its inner end abuts a shoulder 11 formed in the shaft. This sleeve has secured to its outer end as by a screw 18, the hand 22. The inner end of this sleeve has the gear 14 rotatably mounted thereon. The gear is fixedly secured to the sleeve for rotation therewith.

The gears 14 and 15 are each provided with twelve teeth which on the two gears extend relative to each other in opposite directions. These gears are provided with loosely meshing projecting

portions

19 and 88 respectively which permit limited rotational movement of the gears. A coiled spring 8| is disposed in confronting

circumierential grooves

82 and 83 of the gears 14 and 15 respectively, one end of this spring being anchored to the gear 14 and the other end being anchored to the gear 15.

The shaft 31 has xedly mounted thereon a cam member 84 which is adapted when rotated to successively engage an arm 85 and an arm 86. The

Varm 85 is xedly secured at one end to a shaft 81 which is rotatably mounted in the

plates

26 and 21. The arm 86 is secured at one end to a shaft 88 which is rotatably mounted in the

plate members

26 and 21.

The arm 86 is normally held in engagement with a stop pin 89 by means of a spring 88 which is anchored at its free end to plate 26 as shown at 9| and is secured at its other end tol the shaft 88. Secured to the shaft 88 and outwardly dis- SOL posed relative to plate 25 is an arm 92. This arm at its outer end has pivotally mounted thereon a push pawl 93 which is normally actuated by a spring 94 into engagement with the teeth of gear l5. It will therefore be evident that when the arm 8S is moved by the cam member 84 in a counter-clockwise direction, the push pawl 93 will act to advance gear 'I4 one tooth. rIhe gear 'M is retained in the advanced position by means of a slip pawl 95 which is constructed of spring material.

The arm 85 is normally held against a stop pin S5 by means of a spring 9i' having its ends respectively connected to a hook latch 98 and an anchor 00 on the plate 25. This spring acts to cause the hook latch to move in a clockwise direction so as to normally engage the teeth of gear l5 to prevent rotation of the gear in a clockwise direction. When, however, the hook latch 00 is released by virtue of the cam member B4 engaging the arm S5, the gear l5 is free to move and advance the hand 22 to the next month indicating numeral.

It will be obvious that since the cam 04 makes a complete revolution with the shaft 31 during each month, advantage of the movement of this wheel may be taken to first advance the gear 'M to tension the spring 8| so that when gear 'l5 is released at the end of the month, the hand 22 will be moved with a snap action.

Day of month mechanism Since the escapement wheel 38 is provided with thirty-one teeth and is advanced one tooth every twenty-four hours, it is only necessary to secure the indicating hand 23 to shaft 3T in order that this hand shall be moved one indicia each day of the month. The escapement wheel will be advanced twenty-eight, twenty-nine, thirty and thirty-one steps in single tooth movements respectively, depending upon whether or not the month has twenty-eight, twenty-nine, thirty or thirty-one days therein. In order that the escapement wheel shall make a complete revolution each month regardless of the number of days therein, it will be evident, for example, that in a twenty-eight day month, the indicating hand will have to move from numeral twenty-eight to numeral one. In other words some means must be provided for augmenting the normal advancement of the wheel so that at the end of the respective month, the indicating hand will move a distance corresponding to four teeth on the escapement wheel for a twenty-eight day month, three teeth for a twenty-nine day month, two teeth for a thirty-day month and will move one tooth for a thirty-one day month in going from the last day of any given month to the first day of the next succeeding month.

The single tooth step advancement of the escapement wheel 38 and consequently the hand 23 is augmented at the end of the month to automatically compensate or correct for the variable number of days in the respective calendar months and for leap year. This is accomplished through the provision of a forty-eight tooth master gear |50 which is rotatably mounted on a gear plate lill.

Normally, the spring |04 has a tendency to rotate the plate |0| in a counter-clockwise direction and resiliently retains the same against movement in a clockwise direction. Movement of the plate in the rst direction is opposed by engagement of lug |06 with a stop pin |01 which is mounted in the plate 26.

A pin |08 is carried by the escapement wheel 38 and is so arranged that as the escapement wheel is revolved, this pin is brought into engagement with the lug |06, with the result that the plate |0| is shifted in a clockwise direction until the pin |08 disengages the lug. The plate now being released, the spring |04 forces the plate to move in the opposite direction until the lug again engages the stop pin |01. It will therefore be evident that each month of the year, the plate |0| will thus be shifted.

Advantage is taken of this shifting movement of the plate |0| to actuate the master gear |00 so that it will be advanced one tooth each month.

Advancement of the master gear is accomplished by means of a push pawl |09 which is pivotally mounted on the frame 26 and actuated by a spring ||0a into resilient engagement at its free end with the teeth of the master gear. Upon clockwise movement of the plate |0|, the pawl |09 will move into engagement with the following tooth, and movement of the plate to normal position against the stop pin |01 will cause the master gear to be rotated about its axis the distance of one tooth. The master gear is held in shifted or advanced position by a slip pawl ||0 which is constructed of resilient material and secured at one end as by a screw ill to the plate |0I.

The plate I0! also carries an arm ||2 which is pivotally mounted on the plate as shown at H3 for swinging movement. This arm is arcuate in form and at its free end is provided with a stop pin Hl which normally engages the outer edge of the plate to limit counter-clockwise movement of the arm about its pivot under the influence of a leaf spring 5 which is secured at one end to the arm and is held in flexed position by a pin H6. This pin is mounted in the plate |0|.

The outermost end of the arm H2 carries a pin il, which is adapted under certain conditions depending upon the position of lever 2, to engage an abutment flange or shoulder ||8 formed on the outer end of an arm H9, when the plate |0| is shifted in a clockwise direction.

The engagement of the pin l1 with this shoulder will cause a clockwise movement of arm i9.

rfhe arm l I0 is integrally formed with the jaw 5l. The jaws 5| and 52 are interconnected by means of a pair of overlapping ngers |20 and |2| which are respectively integrally formed with the jaws 5| and 52. Now, it will be observed, that if the jaw 5| is rotated in a clockwise direction, this movement through the lingers |20 and |2| will cause both jaws 5| and 52 to be moved outwardly against the pressure of spring 5d a suiiicient amount to enable the block 51 to freely move in and out between the jaws and permit operation of the escapement wheel 38.

.This position 'of' the jaws is clearly shown in Figure 9. The advancement of the escapement wheel will continue until the pin |08 disengages the lug |06 and permits the plate |0| to moveY in a counter-clockwise direction to normal poengages the lug |06. Also that the beginning of the free movement condition will be advanced or retarded depending upon the position of arm H2. By shifting the arm ||2 in a clockwise direction, in which case the stop pin I4 is moved outwardly from the associated edge of the plate the pin ||1 may be caused to engage the shoulder ||8 at an earlier or later time after the beginning of the shifting movement of theplate 0| by the pin |08. The position of the lever ||2 will therefore determine the length of time that the jaws 5| and 52 will be in wide open position, and consequently the number of teeth that the escapement Wheel will advance during the free movement of the block 51. The posi- Vtion of the arm ||2 is determined by a plurality oipins which are carried by the master gear |00 and engage a projection |22 formed on the arm ||2.

Referring to Figure 8, which shows the mechanism in normal position with the jaw 5| latching the block 51 against movement, it will be observed that some of the pins `on the gear |00 are disposed a greater distance from thecenter of the gear than other of the pins. Some of these pins, such as the pin |23, are disposed on a pin circle |24. Other of the pins, such as pin |25, have their centers disposed on a pin circle |26 which is slightly further from the center of the gear than pin circle |24. Also pins such as pin |21 are on pin circle |28 which is of still greater diameter.

It will also be observed that these pins are 'n in each case placed on a tooth radius and that in the case of some of the teeth on the gear |60, there are no pins on the radii of the teeth. In these cases, the projection |22 would not be engaged by a pin and the arm ||2 would be moved clockwise to its stop position.

In general, when the projection |22 is in a space or does not engage any pin, the mechanism will indicate the days for a thirty-one day month. When the projection |22 engages a pin on the pin circle |24, as shown in Figure 11, the mechanism will indicate a thirty-day month. Whenfthe projection 22 engages a pin on the pin circle |26, the mechanism will indicate a twenty-nine day month as shown in Figure l2. When the projection |22 engages a pin lying on the pin circle |28, a twenty-eight day month will be indicated, this position being shown in Figure 13. It will therefore be evident that the pins may be so distributed on the gear |00 as to take care of all the months of a four-year period and thus compensate for the variations in the number of days in the respective months and also leap year. The master gear will therefore make one complete revolution every four years.

Figure 8 shows the normal position of the plate |0| against its stop pin |01 with the pin |00 just engaging the lug |06 to cause shifting of the plate. The master wheel is in position for a thirty-one day month, the projection |22 being disposed in a space. It will be ob- ,served that the pin I 1, during shifting of the plate |0|, will have to move its greatest distance before it engages the shoulder ||8 to open the jaws 5| and 52. Under these conditions, the escapement wheel 38 will continue to advance in one-tooth steps and pin ||1 will continue to apthe position shown in dotted lines |08-C in Figure 10. As the pin |08 moves from position |08--C to |08--D, the pin ||1 will approach but will notV strike .the shoulder ||8 to open the jaws 5| and 52. lT'he pin |08 will disengage the lug |06 and permit the plate |0| to return to normal position. At the same time, the arm 48 will have shifted in a clockwise direction sufciently to disengage the jaw 5| from the block 51 and will have moved in a counter-clockwise direction suliciently to have released the jaw 52 relative Vto the block 51, whereupon the block will pass between the jaws and then move outwardly to latched position as shown in Figure 3. In other words for a thirty-one day month, the jaws are not opened by actuation of the tripping lever H9, but the escapement wheel is advanced one tooth as in the normal manner of operation jproach the shoulder I8 until pin |08 has reached through the actuation of arm 88 as heretofore described in detail. The hand 23 in this case will move from the numeral thirty-one to the numeral one to begin the new month.

Referring to Figure 1l, the shifting of the plate 68| will have advanced the master gear one tooth, and if the next month is to be a thirtyday month, the projection |22 will be engaged by a pin |23 on the pin circle |24. This will move the pin ||1 a little closer to shoulder H8. Under these conditions, when pin |08 reaches the dotted line position |08-B as shown in Figure Vl0, pin ||1 will engage the shoulder H8 and open the jaws as shown in Figure 9. This will enable the escapement wheel to continue moving until pin |08reaches position |08-D, whereupon the plate will be released as before and returned to normal position, and the jaw 5| will again latch the block 51 against further movement. The hand 23 will have jumped from numeral thirty to numeral one to begin the next new month.

If the next month is to be a twenty-nine day month, the position of the various parts will be as shown in Figure 12 with the projection |22 engaging a pin |25 which is on the pin circle |26. Thus the arm |12 is shifted still further in a clockwise direction to bring the pin |1 closer to shoulder ||8, or in other words to make the jaws open sooner. When the pin |08 reaches the position shown in dotted linesV at |08-A in Figure '10, the pin ||1 will have engaged the shoulder ||8 to 'actuate shifting lever ||9 and open the jaws as shown in Figure 9. The escapement wheel will then continue to move and the plate |0| Will again be released when the pin reaches position |08-D as previously. In this case the hand 23 will have jumped from numeral twentynine to numeral one to begin indicating the days of the new month.

Assuming that a twenty-eight day month is to be indicated, the master gear will have assumed a position as shown in Figure 13 with projection |22 engaging a pin |21 on pin circle |28. This is the outermost pin circle and in this position, pin ||1 will be in engagement with the shoulder ||8 so that immediately upon pin |08 coming into engagement with lug |06 to start shifting the plate |0|, the tripping lever I9 will be tripped to open the jaws 5| and 52 to release the escapement mechanism. This will permit the escapement wheel to continue moving until plate lsl is released relative to pin |08, this being when the pin reaches position Hi8-D. In this case the hand 23 will have jumped from numeral twenty-eight to numeral one to begin indicating the next new month.

From the above description, it will be apparent that this invention provides an improved horological device having a calendar mechanism for indicating the current day of the week, day ci the month and the month of the year, in which the mechanism is so constructed that the date denoting indicia will be automatically changed in such a manner as to compensate for leap year and the variations in the number of days in the respective calendar months; wherein the indicating means is moved with snap action; and in which the date indicating mechanism is so constructed that it may be utilized as an attachment for a time indicating device such as a clock, and when so attached will be controlled by the time keeping device.

I am aware that many changes may be made and numerous details of construction may be varied through a wide range without departing from the principles of this invention, and I, therefore, do not purpose limiting the patent granted hereon otherwise than necessitated by the scope and spirit of the appended claims.

I claim as my invention:

l. In a device of the character described a cam member adapted to make a complete revolution each month, a rst gear, a second gear, said gears being coaxially mounted for limited relative rotation and elastically coupled, date indieating indicia successively indicated in response to the movement of said first gear, a releasable detent normally retaining said rst gear against movement, pawl means for advancing said second gear each revolution of said cam, and means responsive to the movement of said cam for releasing said detent subsequently to the advancement of said second gear, whereby the indicated indicium is changed with a snap action.

2. In a device of the character described, a member carrying indicia corresponding to the respective days of a calendar month, means for successively changing the day of the month indicated, said means comprising an escapement, a m-aster gear intermittently advanced once each month, a plurality of pins carried by said gear and disposed at various radii from the center of said gear, a pivoted lever successively engaged by said pins, the position of said lever depending upon the particular pin engaged, means for shifting said lever and gear as a unit about a common axis, and means engaged by said lever when so shifted for controlling the actuation of said escapement.

3. In a horological device, an escapement including an oscillatable arm having a projection thereon, and means to control the starting and stopping of the escapement, said means compris'- ing a pair of latching jaws of different lengths pivoted at their inner ends to a common oscillatable support and connected for simultaneously opening when the longer of said jaws is pivoted away from the other jaw, spring means resisting the opening of said jaws, said arm normally being latched against movement by the engagement of the projection with the outer end of the longer jaw, and means for oscillating said support, movement of the support in one direction disengaging the longer jaw from the projection to enable it to engage the shorter jaw, movement of the support in the opposite direction bringing the longer jaw against said projection, whereby it is pivoted outwardly to open the jaws and release the escapement, the operation of the esc-apement carrying the projection outwardly from between the jaws into latched position.

4. In a device of the character described, a member carrying indicia corresponding to the respective days of the calendar month, means for successively changing the day of the month indicated, said means comprising an escapement,

cam means intermittently advanced once each month, a cam follower having its position determined by said cam means, means for moving said cam means and follower as a unit, and

means operable in response to said movement for releasing said escapement.

5. In a device of thev character described, a member carrying indicia corresponding to the respective days of a calendar month, means for successively changing the day of the month indicated, said means comprising an escapement, a rotatable cam member, a pivoted arm engaged by said c-am member, means for shifting said cam and arm as a unit about a common axis, means controlled by said arm during said shifting movement for releasing said escapement, and means responsive to said shifting movement for rotating said cam member a predetermined amount.

6. In a horological device, a movable member carrying indicia corre-sponding to the respective days of a calendar month, and escapement means comprising an oscillatable pallet arm for controlling the movement of said member, a pair of latching jaws normally operable to release said arm for single indicium changes, and means for augmenting the operation of said jaws to release said arm for plural indicia changes.

'7. In a horologieal device, a movable member carrying indicia corresponding to the respective days of a calendar month, and escapement i means comprising an oscillatable pallet arm controlling the movement of said member, a pair of latching jaws successively operable to release said arm for single indicium changes, and simultaneously operable to release said arm for plural indicia changes.

JOHAN MACHEK.