US3326052A - Escapement between an energy storage means and a driving pinion of stepwise intermittent movement - Google Patents

Description

w. HoLzER 3,326,052 NT BETWEEN AN ENERGY STORAGE MEANS AND A DRIVING June 20, 1967 ESCAPEME PINION OF' STEPWISE INTERMITTENT MOVEMENT Filed April G, 1965 3 Sheets-Sheet l BY www@ ATTORNEYS 2 5 u N e 6G h N S 2W r m w 3 D e AT% N DB3 NM AE V SO NM A ET MN W. HOLZER ENERGY STORAGE PwIsE INTERMITTE June 20, 1967 ESCAPEMENT BETWEEN AN PINION OF STE Flled Aprll C 1965 INVENTOR- By WALTER HOLZ/5R Atrneys June 20, 1967 w. HoLzER 35326052 ESCAPEMENT BETWEEN AN ENERGY STORAGE MEANS AND A DRIVING PINION OF STEPWISE INTERMITTENT MOVEMENT Filed April G, 1965 3 Sheets-Sheet 3 INV E NTOR:

WALTER HOLZER Attorney United States Patent O 3,326,052 ESCAIEMENT BETWEEN AN ENERGY STORAGE MEANS AND A DRIVING PINION OF STEPWISE INTERMITTENT MOVEMENT Walter Holzer, Drosteweg 19, Meersburg (Bodensee), Germany Filed Apr. 6, 1965, Ser. No. 446,027 Claims priority, application Germany, Apr. 24, 1964, H 52,478 1 Claim. (Cl. 74E-1.5)

The invention relates to an escapement arranged between a continuously retensionable energy storage means and a driving pinion which is moved by said means in a stepwise and intermittent manner.

An escapement is already known which is formed by an eccentric cam continuously moved by the driving motor of the energy storage means and moving an arresting member with projections which, at every step, jump from one shoulder to another, the said shoulders being arranged at intervals according to the length of the step.

A disadvantage of that construction was that the projections of the arrester, under the force of the energy storage means, struck against the shoulders upon completion of the step whereby said shoulders and projections, being without any surface contact, were quickly worn away, their functional reliability being thereby diminished.

It was a further disadvantage of that construction that the shaft on which the driving pinion was located had to partly absorb the impacts so that the corresponding bearings had to be .replaced frequently.

Another disadvantage of the known construction was that, with control being achieved by an eccentric cam, the steps were tripped in one of the dead center positions of the said cam. This produced inaccuracies in timing because the continuously moving eccentric cam travelled its shortest distance during the releasing step relative to its angular speed, and consequently the releasing or tripping path which was to determine the exact timing of the interval between steps, was not suiiciently precise.

It is the object of this invention to avoid these disadvantages and to construct an escapement with a high degree of functional reliability in which the tripping path can be adjusted with great accuracy and in which the entire arrangement is cheap and quick to produce and easy to adjust.

According to this invention the solution of this problem resides in the arrester being in the form of a slider reciprocated by an eccentric cam, the slider carrying projections extending into guideways permitting freedom of motion in the direction of reciprocation, the lengths of said guideways being limited by shoulders arranged at distances corresponding to the step length, lthe shoulders being staggered relative to each other by at least the width of one projection in the direction of movement of the slider, the projections during their reciprocating to and fro movement springing from one shoulder to another and thereby permitting the stepwise intermittent movement of the guideway-carrying driving member connected to the energy storage means and the driving motor.

According to this embodiment, the projections are guided in guide paths which are limited in their length by shoulders. This, therefore, already achieves a more exact tripping because any rebounding is avoided, the projections being guided. rI'he further tripping movement by a slider again ensures that `the projections do not strike shoulders which are rigid with the housing. Instead both the shoulders and the projections are provided in moving parts so that more accurate synchronization to one another is possible.

ICC

One possible embodiment consists in the guideways for the projections being in the form of recesses arranged concentrically to the axis of the eccentric cam and overlapping each other at their ends by at least the heights of the projections, said recesses being staggered radially relative to each other by the widths of the projections, the outer edge of the inner guideway being continuous with the inner edge of the outer guideway at the overlapping points. This construction is especially suitable if the driving part is always to rotate in steps of 180 so as to produce simple rotation, although a stepwise longitudinal movement is also possible. It is only necessary for the projections to be at a xed distance from each other on the slider and that they be moved to and fro in such a way that they will alternately enter the one or the other of the guideways, whereupon each of these guideways will allow the driving part to rotate through 180 during each step.

It is furthermore expedient for the shoulders limiting the length of the guides to be arranged symmetrically to the axis of the eccentric so that, when the shoulders bounce against the projections, the shaft on which the eccentric rotates is relieved of the impact.

With this construction, a left and right-rotating torque is generated by the impact on either side of the axis of the eccentric so that these torques cancel each other out and so that the impacts do not strain the shaft that carries the eccentric. The bearing which would otherwise have to absorb this impactV therefore enjoys much longer working life and the entire arrangement is far more reliable in operation.

A further embodiment consists in the recess in the slider, in which the eccentric cam rotates, being suiieiently large for the projections entering the guide when the drivingpart .is released to allow movement of the slider independently of the cam. l

This feature pioneers an entirely new field in such escapements. Hitherto, the projections were only used to allow movement of the driving part by entering one or other of the guides. Now, the projections are 4also used in that, `during this rotary movement, they can also move the slider, yas will be described in detail hereinafter.

AIt is furthermore important for lugs to be provided in the recess symmetrically to the axis of the eccentric so that they contact the eccentric member at a point of which the line of connection with the axis forms an angle, for example a angle, with the direction of movement `f the slider.

The eccentric cam now no longer causes the tripping when it is in the path of movement of the slider. In this position, the path travelled is very much smaller for the same angular speed than when the eccentric c am was moving the slider before it reached the described position. To a certain extent, the sine and cosine functions have been reversed. In any event, the eiect of having -the lugs so arranged is that the trippingand releasing of the drivin-g part is very accurately timed. It is therefore suflcient to have very slight changes in the angle o f the eccentric cam in order, within this range, to trip or release, or alternatively arrest, the driving part. 4 I To prevent the shoulders being damaged as they rebound Iagainst the projections during the intermittent movement of the assembly and by reason of a possibly excessive surface loading, it is furthermore important for the guide faces which abut laterally against the projections to be at a diminishing distance from the central point the farther they are away from the shoulder, so that, during the rotary movement of the disc-shaped drive part, the latter produces a dis-placement such that approximately Ithe entire sur-face of the shoulder strikes against the projection upon completion of the step. l v

Whilst, therefore, one shoulder is sliding off the projection, the fact that an eccentric face of the guideways is passing the fixed projection means that slider is again displaced sufficiently far for the next shoulder, which now strikes the next projection, to strike the entire face thereof.

In forder to simplify manufacture, it is important for the slider to have arcuate projections which are arranged in a mutually staggered formation.

A further simplification in design is achieved by the driving part being a disc carrying on one side recesses to kact as guides and on the other side pins or teeth which `form the driving pinion.

A further simplification in construction which saves greatly on space, consists in the driving part having a shaft which at the same time forms the bearing for the drive wheel of the energy storage means and a back taper for one end of a flat traction spring, of which the other end is connected to the driving gear wheel inside which the spring is accommodated.

In this way, energy storage means, eccentric cam, arresting member, the driving member and driving pinion are to a certain extent combined into one part.

It is further expedient for the driving gear wheel at the same time to be positively connected to the eccentric cam.

Embodiments of the invention are illustrated in the drawings. Further features of the invention will become manifest from the description which follows and from the drawings, in which:

FIG. 1 shows diagrammatically and in cross-section the driving motor with gearing, energy storage means, escapment and drivin-g pinion;

FIG. 2 shows diagrammatica-lly a driving member with the slider and its projections and the eccentric cam which moves the slider back and forth;

FIG. 3 corresponds to FIG. 2, but the recess-in the slider is so chosen that tripping occurs at a more favourable time; FIG. 4 shows, as a detail, the driving part with guideways of special construction to permit displacement of the slider during the stepwise movement;

' FIG. 5 shows the slider with projections acting as the arrester part, which finds application with the driving parts in FIG. 4;

FIG. 6 shows diagrammatically the parts illustrated in FIGS. 4 and 5, operatively connected;

FIG. 7 is a cross-section through the driving part in FIG. 6, taken along line VII-VII, and

FIG. 8 shows diagrammatically a possible drive part engaged in a toothed rim.

FIG. 1 shows a driving motor 1 which is accommodated or flanged into a bed plate or housing part 2. Between it4 and the other housing part 3 is the entire escapement mechanism with driving part and driving pinion. Pinion 4 ofl driving motor 1 engages in gear wheel 5 of which pinion 6 in turn engages in gear wheel 7 of which pinion 8 engages in gear wheel 9 and, nally, pinion 10 of this last-mentioned gear wheel engages in driven gear wheel 11 explained in greater detail hereinafter. Said -driven gear wheel 111 is recessed on one side, the hollow space serving to accommodate a fiat spiral traction spring 12. The inner end 13 of said spring is connected to shaft 14, the outer end 15 with gear wheel 11. Freely rotatable on shaft 14 is eccentric cam 28 which serves to move the slider 17 with its projections 17, 18 back and forth as described hereinafter. Finally, said shaft 14, in the embodiment illustrated, ends in a drive part 19, that side of said drive part 19` which is facing towards gear wheel 11 having recesses 20 which will hereinafter be referred to as guideways. On the other side, this drive part forms driving pinion 21, which in the embodiment illustrated being formed by two pins 22 which, as is illustrated in FIG. 8, engage in teeth 23 provided for example on the periphery of a control plate 24 illustrated only diagrammatically in FIG. 8, said control plate 24 having for example known concentric cam paths in order to switch or move contact or scanning levers arranged in groups.

FIGS. 2 and 3 show with a slight modification how the arrangement functions. Slider 17 is moved to-andfro Vin the direction of arrows 34 and 38 and between guides 25 and 26 integral with the housing, when the permanently rotating driving motor 1 turns gear 11 and eccentric cam 28 in the direction of arrow 29. Recess 30 in slider 17' cooperates with cam 28 to cause the carriage to `be moved back and forth. The slider carries projections 17 and 18, having the form of, for example, outwardly ben-t lugs. It will be seen that, when the projections are of height 31 and width 32 as viewed in FIGURE 2 and are in the positions shown, part 19 can make a half revolution in the direction of the arrow 37. The distance between projections 17 and 18, as illustrated in FIG. 2, is indicated by reference numeral 33. After the projections are moved in the direction of arrow 38, they will enter guideways 35, 36 respectively. These guides are shown in FIG. 1 as recesses 20, but can take any other form at will. After the eccentric cam 28v has moved the projections 17 and 1-8 in the direction ofthe arrow 38 suciently for them to enter the free-cross-sections of guides 35, 36, then driving part 19 moves suddenly in the direction of arrow 37 through 180.

'FIGURE 2 shows therefore that after projections 17 and 18 have been moved by the cam 28 in the direction of the arrow 34, the drive part 19 will rotate in the direction of the arrow 37 until the projections 17 and 18 are encountered respectively by shoulders 41 and 42 at the ends of guideways 35 and 36, but upon continued rotation of cam 28 by gear 11, the projections will again be moved in the direction of the arrow 38 into their original positions, thereby releasing the drive part 19 for another half revolution until the projections 17 and 18 are encountered by the shoulders 42 and 41 respectively.

-In FIG. 3, the same reference numerals designate the same parts. Here, again, it is seen that the overlapping of the guides 35, 36 must be at least as great as the height 31 of the projections and that, furthermore, the lateral staggering of these guides must be as great as the width 32 of the projections. In the case of the embodiment shown in FIG. 3, lugs 43, 44 are provided in recess 30. In this case, gear 11 drives a different construction of eccentric carn 45. The eccentric cam is so shaped that lug 44 is for example contacted already at point 46. The connecting line 47 between this point and the middle point of shaft 14 encloses angle 48 with movement of carriage 17 in the longitudinal direction. In this position, for the same angle of adjustment of eccentric cam 45, a far greater path is `associated with slider 17 than if the eccentric cam 45 ldid not move the carriage 17 until it were approximately in the direction of movement or of arrow 49 of carriage 17. By this arrangement, therefore, a far more exact and precise operation is achieved.

A further improvement is achieved by the construction in FIGURE 5 where the same reference numerals designate corresponding parts. In `this illust-ration again, it is shown that the same angle of adjustment 4'8 of cam 45 corresponds on the one hand in the region of lug 43 or 44 to a path 50 of the slider, and in the region of the direction of movement of the slider, to a path 51. The direction of movement of the slider is produced by guides 52, 53 bent outwardly from the bed plate. Path 51, as `the scale drawing shows, amounts to only a fraction of the path 50. Projections 17, 18 are of arcuate shape. In FIG. 4, these projections 17, 18 are drawn within the driving part 19, together with the interval between them, 33.

`In a manner similar to FIGURE 2, the modification in FIGURE 4 is provided with guideways 35, 36 whose ends, as shown in the drawing, are of widened cross section. Starting from the hatched areas, when the projections 17, 18 are displaced in the direction of arrow 38, they suc- CeSSVely SSllltl@ the position 57 shown in broken lines land then the position 58 shown in dash-dotted lines. The distance between faces S9 of the guides from the middle point 60 of the driving part, which coincides with the middle point of shaft 14, varies. In the embodiment shown, the projections 17, 118 move in eect downwardly from edges 61 of shoulders 39, 41. Faces 59 of guideway 35, which now pass projection 17 in the direction of arrow 62, press the said projection and, with it, the slider 17, in the direction of arrow 38, so that the slider, when it is struck by the face 39, is then in the position 58 shown in dash-dotted lines or 57 shown in broken lines. The entire face is thus available for the impact.

In FIGS. 6 and 7, the same reference numeral designates the same parts. This illustration serves only to explain once again the interaction of the parts shown in lFIGS.l 4 and 5.

As a eld of application of the invention, reference can be Imade to all possibilities in which an escapement is incorporated between an energy storage means and a driving member and where, at exact intervals of time, a continuously re-generated energy storage means, released by the escapement, drives the driving pinion without the impacts occurring thereby causing rapid Wear and tear of the parts which strike one another in the process.

What is claimed is:

An escapemen-t mechanism adapted .to be connected between a motor-driven train of reduction gearing and a driving pinionV to put the latter impulsively into intermittent stepwise rotation, said mechanism comprising a driven gear adapted to be continuously rotated in one direction by said reduction gearing, a spring having one end connected to said `driven gear and its other end connected to a shaft that is freely rotatable in and coaxially with the driven gear, an eccentric cam attached to and rotatable in unison with said driven gear, a slider moved to and fro by said cam and carrying -two projection-s on one side thereof and aligned with each other in one direction of the to and fro movement of the slider, a disclike driven member secured coaxially to said shaft and having an annular recess on one side of it into which said projections extend, said recess being formed of two semicircular portions which communicate with each other at their ends but one of which portions is Iat a slightly greater radial distance from the axis of the disc than the other portion, the sum of said radial distances bei-ng equal to the distance between the projections so that when the slider is in either of its terminal positions the disc can be rotated only half a revolution but will be free to continue its rotation another half revolution after the slider has been moved into its other terminal position, said driving pinion being carried by the other side of said disc.

References Cited FOREIGN PATENTS 1,333,758 -6/-1963 France.

MILTON KAUFMAN, Primary Examiner.

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