US2421368A - Wheel of variable diameter - Google Patents

Description

June 3, 1947. E. H. AUBERT WHEEL OF VARIABLE DIAMETER Filed Nov. 9, 1942 6 Sheets-Sheet l June 3, 1947. E H, AUBERT 2,421,368

WHEEL OF VARIABLE DIAMETER Filed Nov. 9, 1942 e sheets-sneet 2 In ven for [ln/E HENRI ,4l/136W June 3, 1947. E. H. AUBERT WHEEL OF VARIABLE DIAMETER Filed Nov. 9, 1942 e sheets-sheet 5 [n1/en for [M/LE /lf/V'/ lil/BERT By torn ely.

June 3, 1947. E H, ALMBERT l 421,368

WHEEL OF VARIABLE DIAMETER Y Filed NOV. 9, 1942 6 Sheets-Sheet 4 OO fil-5.9 E310' June 3, 1947. E. H. AUBERT] 2,421,368 l WHEEL oF VARIABLE DIAMETER V Filed NOV. 9, 1942 6 Sheets-Sheet 5 June 3; 1947. n E, H, AUBERT 2,421,368

WHEEL OF VARIABLE DIAMETER Filed Nov. 9, 1942 e sheets-*sheet e 120'22 20110122 fai 68 ,E HAU/661%" Patented `lune 3, 1947 WHEEL F VARIABLE DIAMETER Emile Henri Aubert, Romette, France; vested in the Attorney General 'of the United States Application November 9, 1942, Serial No. 465,945 In France July 17, 1941 11 claims. (c1. r4-244) The present invention relates to a change speed device, including `a wheel or pinion of variable diameter, said device being applicable to chain, belt or cable transmissions and comprising in particular the following features:

The wheel of variable diameter is composed of movable independent elements capable of assuming successive concentric positions, all these elements being, for each position, on one and the same circle. The passage from one position, corresponding to a circle of given diameter, to another position, corresponding to a, circle of greater or smaller diameter, is produced by the spacing apart or the moving together of at least two of the movable elements.

In the case of a chain transmission having a denite pitch, the movable elements each carry teeth and they are arranged in such a manner that, when they are in the position corresponding to the circle of minimum diameter, they are all in Contact with each other and form a continuous pinion in which the space separating each of the teeth is equal to the pitch of the chain.

According to another feature, the movable elements can be held stationary in a certain number of definite positions corresponding to circles, the lengths of the circumferences of said circles being equal to a whole number of pitches. The passage from one circle to the circle immediately larger or smaller is produced by the spacing apart or the moving together of at least two of the movable elements a distance equal to the difference in the circumference of the two circles, said movable elements then forming a discontinuous pinion, but the space separating two adjacent movable elements being always equal to zero or to a whole number of pitches.

The movable elements .are arranged in two groups of side plates which are mounted on the shaft of the device and can have relative angular displacement with respect to each other, said side plates carrying sloped inclines in which are engaged studs rigid with the movable elements. The inolines of one of the groups of side plates has slopes in reverse directions to those of the other group, so that an angular displacement of one of the groups of side plates relatively to the other produces both a radial and angular displacement of each movable element.

Both groups of the incline-carrying side plates can be operatively connected as to rotation when the movable elements are arranged on one of the circles corresponding to a whole number of pitches. These plates can also have relative angular displacements for the passage of the movable elements from one position to another.

Other features will appear from the following description in the course of which it will be convenient to call working length, a definite position of the movable elements on .a circle of definite diameter, corresponding consequently, to a given speed.

In the accompanying drawing, given by way of example:

Fig. 1 is a sectional half view taken along the line l-I in Fig. 2, showing the studs l5 of the movable elements Il of, the present device positioned for the minimum working length, namely sixteen pitches;

Fig. 1A is a sectional half view taken along line IA-IA in Fig. 2;

Fig. 1B is a sectional View showing the movable elements positioned for a working length of seventeen pitches;

Fig. 1C is a sectional view showing the movable elements positioned for a working length of eighteen pitches;

Fig. 1D is a sectional View of the device, looking from the opposite sides of Figs. 1, 1A, 3 and 3A.

Fig. 2 is a section taken .along line 2-2 in Fig. 1;

Fig. 3 is a, sectional half view taken along line 3-3 in Fig. 4 showing the studs I5 of the movable elements Il positioned for the maximum working length;

Fig. 3A is a sectional half view similar to Fig. 1A but showing the movable element-s Il positioned for the maximum working length of twenty-four pitches;

Fig. 4 is a section taken |along line 4--4 in Fig. 3;

Figs. 5 to 10 are views showing separately members of the apparatus;

Fig. 5 is a sectional detail view similar to the upper left hand portion of Fig. 2;

Fig. 6 is a detail view of a portion of the control device for initiating changes in the working length;

Fig. 7 is a plan view of a movable element or segment of the sprocket circumference;

Fig. 8 is an elevation of Fig. 7;

Fig. 9 is an elevation of the lug carrier for lock.. ing the elements when positioned for the various working lengths, said carrier being mounted on the drive shaft;

Fig. 10 is an edge view of Fig. 9;

Figs. 1l to 13, 13A and 13B are diagrams illustrating the operation of the control device;

Figs. 13C, 13D, and 13E are side, edge and plan views respectively, of a modied form of movable element or segment;

Figs. 14 to 26 show constructional modifications of various members of the apparatus;

Figs. 14 and 14A are end and elevational views respectively, oi a stud which is employed in a slightly modified form of movable element;

Fig. 15 is.-a side e-levation of the movable element for receiving` the stud shown in Fig. 1li;

Fig. 16 is a view showing the relative position of the plates 4 and 'I' for assembling the studsand movable elements thereon;

Fig. 17 is a. sectional view throughFig. 16A

showing the studs in position;

Figs. 18, 18A and 18B are plan, side'v andend views respectively, of still another form of movable element;

Fig. 19 is a perspective View of a modiiied'form f inner spool member;

Fig. 20 is a sectional View showing still another modified form of mo-vable element;

Fig-21 is asectional View showingiamodied form.of. flanged plate structure for supporting thernovable elements;l

Eig. 221s across-sectional View showing aiform ofl changespeed device for receiving a V-belt instead vof achain;

Fig. 23 is a sectional View similar to Fig. 22, showing a constructionk with which a cable is adapted to be associated;

Fig. 24..is.a sectional view showing afmodied form ofI device, whereinvall the movable elements move along radial lines;`

Fig. 25Lis.a.view ofa slightly modified form of control for initiating relative movement between theslotted plates or spools;

Fig. 26 is a view of still another modified form of control;

Figs. 27to.39l are. diagrammatic views showing several modifications ofthe operating-.devices for the change speed mechanisms.

According. to. the. embodiment illustrated. in Figs. l, 1A", 1B, 1C; 1D, 2', 3, 3A and 4the `change speed device for a.chaintransmissionraccording to .theinvention is. composed of two spool-shaped members Il and 2."f1'tting into.. each other, the member I comprising two parallel side plates and 4 fixedlyv mountedon the shaft 5 of the transmission andmemb'er 2"comprising two parallel .side plates 6" and 'I" rotatably mounted around the hubs of members 2 which .in turn are mounted on the shaft 5. These plates areconnecteditogether by pins 8. The proximate inner facesof plates. sand 4 are respectively disposed adjacentthe outer faces of plates 6 and'I. In theside plates 3 and 4 of members I are cutout slots 9 Adifferent* from each other but parallel on both side plates, and in the side plates 6 and 1 of member 2 are'also cut out slotsr II]y which will be` hereinafter called inclines, the inclines IB being sloped'in reverse direction-to the slots 9. Between the side plates 6I and'T are arranged movable'elements II (see also Figs. 7 and 8) each comprising two teeth I2"spaced apart toadistance equal tothe pitch p of a chain C (Fig. 1D). Said elementsl II'are so constructed that, when two of them are in contact, the'distance between one tooth of one andthe adjacent tooth of the other isjequal tothe. pitch p (Figs. 1A and 1B). Eacl'relement II has two lateral parallel lugs I 3` in'contact with the inner proximate facesof the side plates and. I.` Eachelement also has two studs. I 4 and I5`securedatthe ends. of element II on the'lugs I3at the .levelofthe pitchcircleor working length;Ef(Fig.. 1A), vone of;said.studs penetrating an incline I0 and a slot 9 of the side plates 6 and 3, and the other of said studs penetrating the corresponding incline and slot of the side plates l and 4.

Figures 1 and 1A illustrate the change speed device when adjusted to a minimum working length E of sixteen pitches p, that is to say, the sprocket has sixteen teeth'forrned on eight segments or. elements II, each element'having two teeth and the elements abutting each other (also see Figs. 1A and 1D). The number of slots 9 and inclines I0 of each of the side plates 3, 4, 6 and 1 is therefore eight.

The maximum working length E8 is twentyfour pitches- (Figs. 3 and 3A) and corresponds to a discontinuous pinion having eight empty spaces each equal to the pitch p, and the space separating the adjacent teeth of two elements spaced from each other being then twice the pitch p. The total number of possible working lengths is nine, namely E, Ethrough E8, each working length differing fromthe preceding one by a spacingapart' of. apair of elements a distance equal to thepitch p, and each slotor incline being formed by abroken line comprising eight straight lines endto end, theintersection of two straight lines corresponding. to a given working length. Fig. 1B illustrates the spacing of the elements I! for aworking length. E1 of seventeen pitches, whereas. Fig. 1C rillustrates. the spacing for the succeeding working length E2 of eighteen pitches. For each succeeding working length, another pair of vabuttingelements `will vbe spaced apart the distance p to thus enlarge the pitch diameter.

The slots 9 and inclines I0 are traced in such a manner that the pOints Where the slots and inclines cross each otherfor any given position are always all on one and the same circle and so that the passage from a working length to the next larger workinglength is effected byfspacing apart two adjacent elements II a distance equal to pitch p.

A'tboth ends lof one andthe same diameter of the incline-carrying side plate 'I are provided two bosses I 6 and I'I, having notches I8 and I9 respectively therein. Onthe periphery ofv the slot-carrying side; plate 4; are provided notches 20, 2M; 2Gb, 20c, 20d, 20e, 20'1, 20g, and 20h, equal in' number to the number of working .lengths provided, that is to say, nine' in the case chosen.

Against the sideplate. 4, and loosely mounted on the transmission shaft 5, is arranged a plate 2| (see Figs. 1, 1A, 1D and 9) carrying two lugs 22 and 23. Theselugs constantly engage notches I8 and i9 respectively of' the side plate T, and these lugs are also capable of entering the notches 2l), 20a, 20h', 20c, 20d; 20e, 20j, 20g and 2th' of'side plate 4.- Tneplate 2'I Vwill'be hereinafter called the lug-carrier. The lug-carrier has a center slotv 24' whichpermits a radial sliding movement of the carrier relative to shaft 5.

Theiradial movements ofthe lugcarrierfl are obtained by the engagement of. onev or the other ofthe lugs 22 and. Z3' with a cam 25.(Figs. 1D, 5 ando). Cam 25` is rockably mounted about a spindle 26, securedby anut Elon a'small-plate 28`which'plate isrigidwithfthe main frame of the apparatus. Theemovements of cam 25 are controlled by a,hand.lever 29. connected to said cam throughthe. medium. of al exible Bowden cable 30 attached to. a spring: 3|y secured in its turn at its other: enden atongue32, said tongue being inte-gralfwithcam 25..r The movement of the. tongue 32.islimited by meansvof two abutments 33Tand`341. Aspring- 35vconstantly-tends The dimensions, shape and position of cam 25 are such that when tongue 32 is pressed against abutment 33 (Figs. 6 and 1D), the cam is located between the two circles or paths dI and d2 followed by the two lugs 22 and 23, the lug following the circle d2 of larger diameter passing above the cam 25 without entering in contact therewith (see Fig. 1l) and the lug following the circle dI of smaller diameter passing under cam 25 (dead center position). When tongue 32 is pressed against abutment 34 (engagement position), cam 25 is in the dotted line position in Fig, 1D and disposed across the path of the lug following the circle dl of smaller diameter. Then, when the lug-carrier rotates in the direction of the arrow F1 (see Figs. 1D and 12), the pin following the small diameter will be lifted by cam 25, which in turn will lift plate 2|. When lug-carrier 2| rotates in the direction of the arrow G and on the path d2 following the circle of larger diameter, the pin will engage the lower face of cam 25 to thereby lower the plate 2|.

The operation of the device is as. follows:

Let us assume that the whole of the transmission operates at the minimum working length E, that is to say, the working length of sixteen pitches p, as illustrated in Figs. 1, 1A, and 1D. In this case, all the movable elements I are in contact, forming a continuous pinion and the studs I4 and I5 are located at the ends of the inclines I9 and slots 9 nearest to shaft 5. Lug 22 is engaged in he bottom of notch I8 and also in the bottom of notch 20, thus securing both members I and 2 together for rotation with shaft 5 in the direction of the arrow F1, lug 22 followingthe circle oil of smaller diameter. If it is then desired to pass to a working length E1 of seventeen pitches immediately higher (see Fig. 1B), the hand-lever 29 is actuated in the direction of arrow f and cam 25 rocks in the direction of arrow F (Figs. 1A and 6).

If the first lug which passes opposite cam 25 is lug 23 which follows the circle d2 of larger diameter (Fig. 1D), it passes on the upper half of the cam 25 causing it to rock, spring 3| allowing this movement without having to abandon the hand-lever 29, and noth'ing takes place. On the contrary, as soon as lug 22 passes opposite cam 25 (Figs. 1D and 13), it abuts against the upper surface of the latter. The lug is then lifted and disengages from notch 20 of disc 4. The lug-carrier 2| is also lifted in its turn the same amount and the opposite lug 23 takes a bearing on the periphery of side plate 4. Lug-carrier 2| is then wedged and stops, which simultaneously causes the stoppage of member 2 constantly connected thereto, member I continuing to rotate with shaft 5. As soon as a notch 20a of disc 4 is opposite lug 23, the latter which was firmly pressed against the periphery of disc 4, enters said notch, members I and 2 are then again rendered rigid together, lug 22 can continue its movement riding up on cam 25 and pass beyond it, causing it to rock against the action of spring 3|. If the hand-lever 29 is abandoned, said cam 25 then comes back under the action of spring 35 to its dead center position, as shown in bold lines in Fig. 1D, after which the pin 23 will follow circle dl and pin 22 follow circle d2.

During this operation, the movement of the movable elements was as follows:

As soon as both members I and 2 are no longer operatively connected as to rotation and as member 2 is stopped, member I continuing to rotate, said members perform a relative angular movement with respect to each other, which will move the elements outward from pitch circle or working length E (Fig. 1A) to pitch circle or working length E1 (Fig. 1B). The points where the slots 9 and inclines I0 cross each other are therefore displaced, which points determine the radial positions as well as the circumferential positions of studs I4 and I5. The elements II have followed said movement by remaining constantly on one circle for each intermediate position betweencircles E and E1, and the elements also remain in an end-to-end contact, with the exception of two which are spaced from each other (see Fig. 1B) This end-to-end contact is necessary because the circles corresponding to the intermediate positions have increasing diameters and the number and dimension of elements I are invariable. Consequentlyone of the elements I I has moved according to a radius, the adjacent element, in the reverse direction to the direction of rotation F1, has been simultaneously subjected to a radial displacement equal to the preceding one and a slight angular displacement in the direction of rotation, the following element to a radial displacement, always constant, and to an angular displacement slightly greater, and so on, up to the last element which has been subjected to the maximum angular displacement. The notches 20, 29a, 29h, 29e, 29d, 20e, 20f, 20g and 20h are arranged at the periphery of side plate 4 so that the relative movement of members and 2 determining the passage from the position corresponding to the engagement of lug 22 in the notch 29 to the following position corresponding to the engagement of lug 23 in notch 20a determines an angular displacement of element II which has moved away from the adjacent one, such that the total movement which has taken place spacing apart these two elements is equal to a pitch p.

On the other hand, it will be seen that lug 22 alternates with lug 23 during the successive engagements with notches 20, 29a, 2Gb, 20c, 20d, 20e, 20j, 20g and 20h, both of said lugs being diametrically opposed. The notches are distributed on two opposite sectors of circles, the notches 20a, 20c, 20e and 29g, corresponding to the odd working lengths of seventeen, nineteen, twenty-one and twenty-three pitches, being arranged on one of the sectors and the notches 29, 29D, 26d, 20j and 20h, corresponding to the even working lengths of sixteen, eighteen, twenty, twenty-two and twenty-four pitches, being arranged on the other sector. If, for example, the cam 25 is held in dotted line position in Fig. 1D while shaft 5 continues to rotate in the direction F1, one of the pins 22 or 23 will successively engage the cam each rotation of the shaft and will be lifted by the cam from a notch at the same time, the other pin will be positioned in the succeeding notch. In this manner, the notches 29, 20a, 29h, 20c, 20d, 29e, 291, 29g and 20h are successively engaged inthe order named by lugs or pins 20 or 23. Duringthe movement of the pins from one notch totanother, the elements-I lare moved tofa larger circle,` that `is. to .a larger. 'worknglength` Frexamplawhen pin .23fmovesintonotch 20a; the elements II are positionedon aseventeen pitch diameter circle E.1'(Fig. 1B) whenk pin 22lengages 2Gb', the elements arepositionedon an .eighteen pitch diameter circle E? (Eig: 1C); and-so'. on until the maximum working` length of twentyfour'pitches` is reached (Fig. 3A), atswhichtime the. elements .are .positionedon circle. E8; and pin 22- will bedisposed in notch 20h.

On: thexother hand, .alsoit is .important that it should not` be the. same two elements II' which are spaced from each other for eachworking length. On the contrary, .it isdsira'ble that, at maximum working length (Fig. 3A) each element II should be spaced fromthe adjacent: element according to a distance equal to apitchp. This iseasily obtained by` tracing the slots 9 andinclines I in such amanner that for each change of working length it is a different. element'which isJsubjected only to a radial-displacement correspending to a radial element of incline III-l of member 2. For balancing the various elements in the above mentioned manner, provisions are made so that two successive radial elements of'inclines III` corresponding to two successive changes of workingV length are located on two opposite/sectors ofzthe pitch circle. In other words, two abutting`v elements will be successively spread apart rst .on one side of the pitch circle and then on the .other at points substantially 180 apart. Inclines IUfand slots@ -are so `shapedthat the intersection points will position the elements II in the above-described positions. Of course, to el'ect such a-result, each element is associated withan incline IUand slot 9 which differs in shape from the incline and slot of the remaining elements. This isclearly shown in Figs.A 1 and 3;

Finally, it is to benoted that, inthe case offa transmission having teeth anda sprocket chain of denite pitch, it4 is indispensable that, atV the time the lworking length is changed, the progressive spacing apart of two movablev elements should take place in the part .ofv the sprocket which is not? in contact with the chain, as the elements `inmesh with the chain cannot obviously move away fromeach other. This result is obtained by suitably disposing relatively to the inclines III, the diameter on whichl the two notches I8 and I9 are located, the position-of said diameter. determining thesectorinwhich the elements I I will `be'spa'cedapart'.(Fig'. 1D)

If it. is desired toeiect the operationreverse to the preceding one, that is to say,1to pass vfrom working length oftwenty-four pitchesito a-vwork-V ing length of'twentyethree pitches, the following method will be adopted:

CamV 25. havingbeen `actuated Vby means Vof the handelever 29': and. being. in. the positiony of en-v gagement of 'Fig` 12,1the transmissionshaitf 5r' will be simultaneously 'given at movementi-of 'rotation' inthe direction ofitheiarrow G1, theilug-carrier-SZI then rotating in the .same ldirection, the A.passage of lug 22 following the circle dipf smalldiam'eter opposite `cam -25.`will producernozchange (Eig.` 1D) but as .soon as lug. 232 followingf the circle d2.; of large diameter will come' in.. position it1 abuts against vthe lower face of 'cam' 25', which will tend to cause it' to lower. Whenlowering' the pin 23 will press against:theperipheryrof disc 41' and thuscause' the Yopposite 'lug-2 2 to come out-ofthe notch 20h inwhich-itrwas engaged." The-lugcarrier-2l and member 2fare thenlieldfstationary, member I continuing torrotateiinr .the direction of Athe arrow GI Members :.I .andi2xthen haveza relativermoveimentin'thereversefdirection tothat of the; preceding case;until.pin 23 is pressedintonotch 20g. During :this relative movement of members I 'and 2., elementsll: move inthe directlonior. passing fromv theworking length circleA Ef. of n a given .diameter'to'the workingflengthcircle E7 of smaller diameter. corresponding. to av working length of twenty-three. pitches. The: elements II which were spaced' apart.' a distance 11i-during the corresponding enlarging stepA will be returned inA contact: with eachother. As soon as lugor pin 23 enters 4notch 20g, the discs will 'again' bey rendered rigid together and shaft .5rcan re-assume its drivingiimovementlin vthe direction of the arrowv F11 In the .example described, it: has been assumed that `the'elements II 'havetwo teeth, it is obvious thatsaid elements. mighticomprise a single tooth. An:element of this construction .is shown inFig. 13C.- and. designated by reference character I Ia.

The case. of a change speed device having nine speeds. has been described, but it is tobe understood that the number of` speeds depends .on the successive supplementary intervals created .from the: initial position.

Forv instance, a mechanism of'A eighteen teeth constitutedby.single-tooth movable elements .will correspond*` to a pinion having thirty-six teeth when each tooth has been moved one step4 away from thev Iadjacent teeth on each. side thereof. Thessame mechanism will'correspond to apinion Of'seventy-two teeth wheneach toothhas'been movedtwo steps: away from its adjacent teeth.

For equivalent intervals, a mechanismhaving eighteen'` teeth constituted by movable elements, each having; two. teeth, will'successively correspend to twentyeseven and thirty-six teeth, vpassing of course through all the intermediate positions.-A If this same'mechanismof eighteen teeth isz: constructed in groupsY of three teeth, it will correspond to twenty-four;teethaftereachv element has moved one step away and'` to thirty teeth when each elementl has moved two-steps away.

Regardless of the number of` teeth in each movable element, there are as many'- speeds as there arepossible pitch spacings between' the elements plus one. Thus, an lil/36r mechanism hasnineteensuccessive speeds corresponding to the offsetting of One-tooth at eachv changeoi working speed.

Figs. 14 to 17 illustratearnodiiiedfformofvv a movable element IIb in association with'plate members'lt-f and 'I'. In'thiscase; one head of adouble-headed stud 36y ts in hole 3l' formed' in-thelug I3 of'element IIb and the other head nts` ina hole 35iY formed at one of` theends of each slot` Sand incline I0.A When theV slots 38 in-the sloty Sandincline Ill coincide, a short' slot 39v is formed. rIlhe assemblage' is eilected by bringingthe studs- 36- opposite `the Avarious holes and inserting them therein, then by again impartingY tofbothmembers 4" and 'I' a relative movement so as Jto-restore the studs- 36` to the normal' starting point.

In theccaseof mechanisms having only'slight torquesA to transmit, the movable elements can be constructedsuchas theyI arey illustrated in Fig.I 18, that is to say, by doing away with the lateral lugsandby` placing the studs I4 and I5' directly` in the heel-piccoli@ of` element Ile.'

Fig. l9fillustrates a-constructional modification ofvv an-inner member 2awhichis made in one piece and isprovided with ilanges` IIIA and' 42',

which'l in `turn are provided vwith suitable slotsI 431 9 and 44, allowing the introduction of the movable elements llc when the latter comprises studs I4 and I5 rigid therewith.

Fig. illustrates a constructional modification of light weight movable elements IId of small dimensions. The lateral studs of member lid are formed by sheets of thin resilient steel allowing the elements to be placed in position by pinching them, as shown in the upper portion of this ligure.

In Fig. 21 have been shown members lh and 2h provided with flanges 45 and 46 intended to increase the rigidity thereof. For further increasing said rigidity and at the same time for protecting the structure from dust,vthe slots 9 of disc I can be simply stamped and need not open to the exterior.

Said slots 9, as well as the inclines Il), can be slightly extended at both their ends for collecting and evacuating the foreign bodies which might be introduced in said slots.

In Figs. 22 and 23, methods of construction of movable elements IIe and IIf have been shown where a belt and cable C,1 and C2 are employed instead of sprocket chains. In this case, said elements, instead of having teeth, have a smooth groove.

Also,A in the case of a smooth belt or cable transmission and when the stresses to be transmitted are small, the slots 9 and inclines Il! can be replaced respectively by simple identical arcs of circles 9a and Illa respectively (Fig. 24). In this case, the eccentricity of the movable elements is uniform during a change of working length, all the elements moving away or approaching each other to the same amount, which can only apply, as indicated above, to the case of a small load since even the elements under the belt must move relatively to each other. In this case, changes of working length as gradual as desired can be obtained by increasing the number of notches 20.

Owing to the dimensions of cam 25, thev location of the points where the movable elements move away from each other can be somewhat different accordingly as the change of working length takes place in one direction or in the other. In this case, when the path out of contact with the chain or belt is small (case of an enveloping chain or belt with a returning wheel), it will be advantageous for the cam 25 to be always attacked at the same point, whatever may be the direction of rotation. This result is obtained by means of the device of Fig. 25 in which the cam 25 is replaced by two cams 55 and 5I controlled by a single lever 52 to which they are connected by links 53 and 52, the halfcam 5I'being used by lifting in the case the change of working length takes place with a rotation in the direction of the arrow F1, and

the half-cam 50 being used by lowering in the case of change of working length with a rotation in the direction of the arrow G1.

Fig. 26 illustrates a device for avoiding a change (of the direction of movement before cam 25 is passed). A premature change in direction of movement might effect a locking of the mechanism. For remedying this inconvenience, two xed cams 55 and 55 are arranged on either side of cam 25 and form with the latter, when it is in position of engagement two channels 51 and 58 in one of which is compulsorily engaged the lug which must determine the operation. These fixed cams have the eiect of restoring the lug 22 or 23! to the position it'occupied on or under 10 cam 25 before coming in engagement therewith if the direction of the movement is changed before thelugunder consideration has completely passed cam 25.

In all the foregoing, it has been assumed that the change speed device according to the invention was mounted as a driving wheel of the transmission. It is obvious that said device might be applied as such, as a driven wheel, the actuation being then produced by the chain itself instead of being produced by the driving shaft 5 and one of the spool-shaped members, for instance the slotted member I being connected to the driven shaft by a free wheel device.

In this case, as member I is only connected to shaft 5 when the device rotates in the direction of arrow F1, it will be possible to effect changes of speed in both directions without having to change the direction of rotation; in fact, it sufces to hold one or the other of members I and 2 stationary for the working length to pass to the higher working length or the lower working length.

This result is obtained as diagrammatically illustrated in Figs. 27 to 32 by providing the device with two half-cams 60 and 6I controlled in the same manner as cam 25. The half-cam 60 plays the same. part as cam 25 for passing from a given working length to the succeeding longer working length by braking member 2f and the half-cam 6I cooperating with a projection carried by member If. TheV surface of cam 6I which can rock about the spindle 63 is divided into three parts: an incline A-B, a circular part B-C having as axis the general axis of rotation when cam 6I is in position of engagement, and a nose C--D. Let us assume that the device constantly rotates in the direction of arrow F1, the changes of working length in the direction for passing from a given working length to the succeeding shorter working length take place by stopping member 2f by means of cam 60, as indicated above for cam 25. Ifit is desired to return from the shorter working length to the longer Working length,cam 5I is placed in engagement (Fig. 28). As soon as lug 22 which, for instance, is that which is then engaged'in one of the notches 20, 20a, 20h, 20c,

20d, 20e, 20j, 20g and 20h comes in position, it

rides up the incline A-B and causes vcam 6I to rock about the spindle E3. As soon as the .projection 62 comes in position in its turn, it abuts against the end of cam 6I at the moment lug 22 has reached B and is disengaged from the notch 20 in which it was housed (Fig. 29). Member I f is then stopped and member 2f continues -to rotate While lug 22 follows the circular path B-C. During this time, another of the notches 20, 20a, 20h, 20c, 20d, 20e, 20), 20g and 20h has come in front of the opposite lug 23 which has engaged therein, and lug 22 can then ride up on the incline C-Dand pass over cam 6I by causing it to rock in the reverse direction to the preceding one and thus releasing the projection 62 which allows members I and 2 operatively connected together by lug 23 to resume their common movement.

In Figs. 33 to 35 have been shown various modications of the .profiles of members I and 2 which increase the smoothness of the speed changes.

Although the notches 20 are shown on a straight line, the device when constructed has the notches arranged on a circle. Fig. 33 diagrammatically shows the simplest profile; The incline-carrying member 2g has two diametrically opposed slots I8 .and the slotted disc Ig a series of notches 20. The lug 22 passes from one notch 20 to the other com- 11 pletely immobilizing member 2g .at the moment the working lengthl is changed.

In Fig. 34, the` general arrangement is. the-same, but the notches of the slotted memberfare joined, not by a circularportion -as in Fig. .33, vbut by bosses vv64. Lug 22, instead of completely stop- -ping the incline-carrying'member'Zh at -a definite point will have a slight 4displacement on thel cam due to the heightof the vboss r64 and, instead of the member 2hl being completely held stationary during the change .of speed, it will be simply braked relatively to the slottedfmember. This method allows a smoother .change efe-speed.

In Fig. 35 is shown `a `device allowing a more important movement of Yboth members llcand 2k during the change of lworking length "and, therefore, a gearing-down allowing 'greater smoothness. Instead of the incline-carrying member 2k: being provided with only two .diametral slots, it can also be divided by notches "65. Thel distance between the notches 65 of member -2lc less the distance between the notches 20 of lmember I represents the relative movement necessary for the changes of working length.

When atransmissionhaving wheels of variable diameter is at'I its minimum'working. lengthy or -at its maximum working length, .theengagementof the cam will impart-.a shock to-.the mechanism. A devicev illustrated in Figs. -36 to `39..preventsthe cam'from coming in engagement'feven when the control thereof isactuated.

yThe lug-carrier 2Im is A4provided with a stud which, in itsnormalpositiom'at all' the intermediate speeds, isnot located inthe `zone ofthe cam. InFig. V37 will beseen the mechanism at an intermediate working length. The operation is normal,lug :2'2 and-withit the lug-.carrier 2 Im is about to be lowered by cam2tm-V andthe 'change of length will take` place.

In Fig. 38, the mechanism. isillustrated: at Vone of the two extremeworkingilengthsgand rotating inthe direction'othezarrow Gl. YThefstudehas been lifted by;a boss `fil carriedby .a flange 68 rigid with the .slotted member l. Inthis :new position, .stud '66 zcauses cam 25 to .rock (which cam. is connected"toitsscontrolbyla spring allowing said movementeven 4when the 1.control lever is maintained inposition) atthemomentlug 22 comesinposit-ion and the latterlrgoesbeyond the .cambyl passing over it.

-If the movement'takesplace inreversedirection (Fig.'39),'then it isilug 22 whichfcauseslthe cam to rock justr'beforethe passage .of stud66,.in other words, stu'dand lug mutually cancelrthe cam.

For' the other eXtreme working' length; it is .the otherdiamet'ral end of the'lug-carrierwhich carriesa cancelling stud placed in,position=at said latter working length byanother yboss vtcarried by ther flange.

The change -speed` device -zaccording vto the inventioncan be applied to all'transmissionsof the chain, belt o-r cable-typel.and,in particular, von bicycles, and it is mountedin combination'with a chain or belt-tightener of'any -knowntype The device can also v.bemounte'd both on-the driving wheel .and on the driven wheel, which can .allow ythe .chain-,tightener .tobe done away with when .the diameters of `both Wheelsvaryasimultaneouslyand in .reverse direction.

-Having now described my .invention vwhat I claim as new anddesire tosecure; by Letters. Patent is:

1. In a. change speed..deviceorfflexible .transmission .means such as I.a chain, beltcor the like,

va wheel ofvariable diameter comprisinga plurality of transmission receiving segments supported by said wheel and concentrically positioned about the axis of rotation of the wheel, said `segments being in contact with each other when positioned along a circumference of minimum diameter, means individual to each of two adjacent segments for shifting said segments outwardly to a larger concentric circumference and also for spacing the two adjacent segments apart a distance equal to the difference in the lengths of the two circumferences, and means individual to the remaining segments for shifting said segments in contacting position to said 4other circumference simultaneously with the shifting of said two adjacent segments.

2. In a change speed device for flexible transmission means such as a chain, belt or the like, -a wheel of variable diameter comprising two concentric relatively rotatable spool-shaped members, each member having a pair of flanges respectively engaging the flanges of the other mem- \ber, one of said flanges having a plurality of cireumferentially inclined grooves therein and the engaging flange having a plurality of circumferentially and oppositely inclined slots therein, which slots respectively intersect with the inclined grooves, and a plurality of transmission receiving segments supported by said grooves and slots at said intersections whereby'relative rotation of said flanges will vary the radial positions of said segments.

3. In a change speed device for flexible transmission means such asa chain, belt or the like, a wheel of variable diameter comprising two concentric relatively rotatable spool-shaped Amembers, each member having a pair of flanges respectively engaging the flanges of the other lmember, one of said flanges having a plurality of circumferentially inclined grooves therein and the engaging flange having a plurality of circumferentially and oppositely 1 inclined slots therein, which slots respectively intersect `with the inclined grooves, a plurality of transmission receiving segments supported by said grooves and slots at'said intersections whereby relative rotation of saidflanges will vary the radial positions of said segments, `a radially movable lockplate constantly engaged with one ofsaid flanges, and means for releasably connecting Vsaid'plateto said other flange to cause both of said flanges and said plate to rotate together.

4. .In a change-speed .devicefor flexible transmission means such as a chain, beltor thelike, a wheel of variable diameterA comprising two'concentric Arelatively rotatable spool-shaped members, each member having 'a pair of flanges respectively engaging the flanges of the other member, one of said yflanges having -a plurality of circumferentially and inclined grooves therein and the engaging flange having a plurality of circumferentially and oppositely inclined slots therein, which slots-respectively intersect vwith the inclined grooves, a plurality of transmission receiving segments supported by said groovesiand slots atsaid intersections wherebyrelativev rotationof said flanges will vary the. radial positions of said segments, means for rotating one of said members, and means for successively locking and unlockingsaid flanges y.at a plurality. of `relative angular `positions while said driving vmember rotates.

5. In a change speeddevicelfor flexible'transmission meansy such as a.chain,vbelt orthe like, a wheelof variable vdiameter comprising .a2 rotatable support, a coaxial support rotatable relative to said first support, a plurality of elements equally spaced along a given length of a pitch circle concentric with said axes of rotation, each of said elements being provided With a contact face for receiving said transmission means, means operable by the relative rotation of said supports for radially shifting one of the elements of said given length to a second pitch circle concentric with said axes of rotation, means simultaneously operable by said relative rotation of said supports `and individual to each of the remaining elements for shifting the remaining elements of said given length to the second pitch circle While maintaining the initial spacing of the elements throughout said length, means for locking said supports against relative rotation at xed angular positions, means for releasing said locking means at said positions, and means for automatically operating said locking and releasing means at said positions alternately in succession during the continued rotation of one of said supports.

6. In a change speed device for iiexiblew transmission means such as a chain, belt or the like, a Wheel of variable diameter comprising a pair of relatively rotatable disks, a plurality of segments supported by said disks and circumferentially spaced along a circle concentric with the axis of rotation of said disks, each of said segments being provided With a face for receiving said transmission means, means jointly carried by said disks and including a pair of oppositely and circumferentially inclined cam surfaces for shifting one of said segments radially oi' said axis to a second circle concentric with said rst circle, and means jointly carried by said disks and including a second pair of oppositely and circumferentially inclined cam surfaces for simultaneously shifting the adjacent segment radially and circumferentially to said second concentric circle While maintaining a constant spacing from said first segment.

7. In a change speed device for flexible transmission means suchas a chain, belt or the like, a wheel of variable diameter comprising a pair of relatively rotatable disks, a plurality of segments supported by said disks and equally spaced a given distance apart along a circular arc concentric vvith the axis of rotation of said disks, and means operable upon the relative rotation of said disks and individual to each of said segments for simultaneously shifting the latter as initially spaced to another circular arc concentric with said first arc.

8. In a change speed device for flexible transmission means such as a chain, belt or the like, a Wheel of variable diameter comprising a plurality of abutting segments supported by said Wheel and concentrically positioned about the axis of rotation of the latter,^each of said segments being provided with a face for receiving said transmission means, means individual to each of an adjacent pair of said segments for separating the latter segments a distance equal to the diierence in the lengths of said respective circumferences upon which the segments are successively positioned and also for shifting the separated segments to another concentric circumference, and means individual to each of the remaining segments for angularly and radially shifting said remaining segments in abutting relationship one with another to saidother circumference simultaneously with the shifting of said pair.

9. In a change speed device for iiexible transmission means such as a chain, belt or the like, a wheel of variable diameter comprising a plurality of equally spaced segments supported by said Wheel and concentrically positioned about the axis of rotation of the wheel, each of said segments being provided with a face for receiving said transmission means, means individual to one of said segments for shifting the latter along a radial line to another concentric circumference, and means individual to each of the remaining segments for respectively shifting the succeeding remaining segments from said rst concentric position over progressively increased distances to said other circumference along paths disposed obliquely to radial lines and simultaneously with the shifting of said rst segment.

10. In a change speed device for iiexible transmission means such as a chain, belt or the like, a wheel of variable diameter comprising a rotatable support, a coaxial support rotatable relative to said iirst support, a plurality of elements equally spaced along a given length of a pitch circle concentric with said axes of rotation, each of said elements being provided with a contact face for receiving said transmission means, means operable by the relative rotation of said supports for radially shifting one of the elements of said given length to a second pitch circle concentric With said axes of rotation, and means simultaneously operable by said relative rotation of said supports and individual to each of the remaining elements for shifting the remaining elements of said given length tothe second pitch circle while maintaining the initial spacing of the elements throughout said length.

11. In a change speed device for exible transmission means such as a chain, belt or the like, a Wheel of variable diameter comprising a pair of relatively rotatable disks, a plurality of segments supported by said disks and equally spaced a given distance apart along a circular arc concentric With the axis of rotation of said disks, means operable upon the relative rotation of said disks and individual to each of said segments for simultaneously shifting the latter as initially spaced to another circular arc concentric with said Iirst arc, and other means individual to each of said segments and operable upon further relative rotation of said disks for separating said spaced segments into two sections by a distance equal to a multiple of said given distance and for simultaneously shifting said segments of the respective sections as initially spaced to a third arc concentric with said second arc.

EMILE HENRI AUBERT.

REFERENCES CITED The following references are of record in the lle of thispatent:

UNITED STATES PATENTS Number Name Date 524,830 Leggo Aug. 21, 1894 598,654 Cleland Feb. 8, 1898 607,322 Adams July 12, .1898 269,916 Chateld Jan. 2, 1883 1,633,746 Jereczek June 28, 1927

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