US1096409A

US1096409A - Variable-speed mechanism.

Info

Publication number: US1096409A
Application number: US56706910A
Authority: US
Inventors: James Arnott
Original assignee: Individual
Current assignee: Individual
Priority date: 1910-06-15
Filing date: 1910-06-15
Publication date: 1914-05-12
Anticipated expiration: 1931-05-12

Description

J. ARNOTT.

VARIABLE SPEED MECHANISM.

APPLICATION FILED MAB.24, 190a. nmuzwnn JUNE 15. 1910.

1,096,409, Patented May 12, 1914.

6 SHEETS-SHEET 1.

WITNESSES INVEN'IUI? 16mm J. ARNOTT.

VARIABLE SPEED MECHANISM.

APPLICATION FILED MAR. 24, 1908. RENEWED JUNE 15, 1910.

1,096,409. Patented May 12, 1914.

HEET 2.

'WITNES SE6.

IN VE'N TOR J. ARNOTT. VARIABLE SPEED MECHANISM. APPLICATION FILED MAR. 24, 1908. RENEWED JUNE 15, 1910.

1,096,409. Pa ented May 12, 191

, 6 SHEETS-SHEET 3.

\IIIIBIIII 'llii lm WITNESSES. I V Mg J. ARNOTT.

VARIABLE SPEED MECHANISM.

APPLICATION FILED MAR.24, 190a. RENEWED JUNE 16, 1910.

1,096,409, Patented May 12, 1914.

6 SHEETS-SHEET 4.

wmv: 555 N nvvs/vmn w f 7 7 mm;

ATTURNEYS J. ARNOTT.

VARIABLE SPEED MECHANISM.

APPLICATION FILED MAR. 24, 1908. RENEWED JUNE 15, 1910.

1,096,409. Patented May 12, 1914.

6 SHEETS-SHEET 5.

Fig? 10 9 y// r HE H II J. ABNOTT.

VARIABLE SPEED MECHANISM.

APPLICATION FILED MAR. 24, 1908. RENEWED JUNE 15, 1910.

1 09 409 A Patented May-12,1914.

6 SHEETSSHEET 6.

Fig. II

"In 1 I 1 q w-mn' um uuuuu n WITNE'S SE15 UNITED STATES PATENT OFFICE.

JAMES ARNO'IT, OF OAKLAND, CALIFORNIA.

VARIABLE-SPEED MECHANISM.

Specification of Letters Patent.

Application filed March 24, 1908, Serial No. 422,936. Renewed June 15, 1-910. Serial No. 567,069.

To all whom it may concern: Be it known that I, JAMES AnNoT'r, a citiz'en of the United States, and a resident of Oakland, in the county of Alameda and State of California, have invented new and useful Improvements in Variable-Speed Mechanism, of which the following is a specification.

This invention has for its object chiefly to provide mechanism for imparting motion at varying rates of speed from a driving shaft or part running at uniform speed, and in the construction of which all the advantages that are obtained by the use of gearing are secured without the objectionable feature of requiring the gears to be disconnected and thrown out of and into gear at the time of varying the speed ofthe driven shaft or part.

The invention has for its object, further, to provide a variable-speed gearing in which the teeth of both the driving art or member and the driven part or mem er are parallel with the axis of rotation.

The invention has for its object, further, to provide a variable-speed gearing in which the driving and the driven elements or members are continually in gear during the period of changing the speed, as well as after each change or adjustment of the speed of the'driven part.

These and other objects and advantages I attain and secure in and by the parts and combination of parts, as hereinafter described and particularly pointed out in the claims at the end of this specification.

The following description explains at length the construction and operation of a machine or mechanism in what I consider to be the best form and manner of carrying out and applying the invention, reference being made therein to the accompanying drawings, wherein I have illustrated a variable speed mechanism embodying the parts and features of the invention.

In the drawings Figure 1 is a plan or topview of a variable-speed mechanism pro-' vided with a reversing gear and with clutches connecting the mechanism wlth and disconnecting it from the machine or part to v be operated. Fig. 2 is a top-view,'on an en larged scale, of the variable-speed gearing without the reversing gears and clutches. Fig. 3 is an end-elevation taken from the left of Fig. 2. Fig; 4 is a vertical transverse sect-ion of the variable-speed gears and the connecting gear and its cnrrier,-the last mentioned gear being broken away on one slde of its axis to expose the gear behind it. Fig. 5 is a front elevation of the mechanism by which the changes in the speed of the driven shaft are effected and controlled through the medium of a hand-lever. Fig. 6 is a detail top-view of a portion of the change-cam shown in Fig. 5 and the slide actuated by it, the same being in part a horizontal section on the line y-y. Fig. 7 is a front view in detail of the carrier in which is mounted the connecting member between the drivin and the driven gears. Fig. 8 is an end-e evation of the means for shifting the connecting gear and the locking-out means that is combined with it,-the cam and parts actuated from it being shown in section. Fig. 9 represents in plan or top-view a modification wherein variations in speed of the driven shaft are effected from a single set or series of alternating cylindrical gears and spiral gears on a common axis. Flg. 10 isa top-view of the gears showing the relative position or relation of the cylindrical and the spiral gears on the same shaft when the latter has been turned one quarter of a revolution from the position in Fig. 9. Fig. 11 is a plan or topview on an enlarged scale of the reversing gear and its clutch. Fi 12 is a longitudinal sectional view of t e same. Figs. 13

and 14 are end-views in detail of the male and female members of the clutch.

The driving and the driven gears in my -.present invention of a variable speed mechanism are of similar construction in being composed each of cylindrical gear elements 2-34, and spiral gear-elements or segments 5-43 which are interposed between the cylindrical gears. and are of such progresslve increase in diameter that each-spiral forms a continuous ascending or increasing gear segment springing from the side of one cylindrical gear at a given point and merging into the next gear in a direction which is the resultant of a circular movement about the axis of revolution and a longitudinal movement alon it.

The teeth bot in the cylindrical gears and the spiral segments are uniformly parallel with the axis of rotation in both sets of gears, and at their junction with the cylin-- drical gears the teeth of the spirals are formed by prolonging or widening the teeth of the circular gears. The pitch or advance of the spiral and the increase in its diameter cause the spiral to merge at both ends in the cylindrical gears, producing a smooth and continuous way or transfer of the spurgear 03 from one cylindrical gear to the other of cylindrical gears may be reduced, however, or the range of variation in speed may be increased, by adding another cylindrical gear and another spiral gear element at one or both ends These gears and gear elements can be supported from a common shaft also by a hub and spokes, instead of by a solid center, and the weight of the mechanism considerably reduced. In the construction before referred to, also, it will be noticed that the driving element a of the mechanism and the driven element 5 are placed in the frame on opposite'sides of a connecting spur-gear (Z; the axis fg of the gears being parallel and the driver a being connected with a shaft 10 to which the motive power to drive the mechanism is applied beyond-the end 12 of that shaft. The driven gear I) consequently receives motion from the driver a through the gear d, and as that gear is moved longitudinally or parallel with the axis of rotation of the driver, it will pass smoothly from the circular gear with which it is in mesh at the time-such movement takes place, and by engagement with the spiral element it will travel along that spiral path without interruption of its rotary motion, until it passes from the spiral on to the circular gear into which the spiral merges.

The connecting gear d is movable laterally as well as longitudinally also in order to keep continually in mesh with the gears on both. sides; and to that end it is mounted for rotation in a slidable carrier 15, which is movable longitudinally in the frame h from end to end of the gears a-b, and the gear d is journaled in a slide-box 14: having limited movement laterally in the carrier. The slid'able-carrier 15, as shown in the drawings, is adapted to slide on the guides mm" from end to end, but when it is found desirable roller-bearings may be employed to convert the sliding friction into rolling fric: tion and render'the operation of the carrier less difiicult. The inner box 14 may also be provided with rollers in a similar manner. These movements are controlled by pins 1718 on the top and bottom of the carrier and slots 19-20 in the stationary guides m,

ments.

ocation the operation of which will be hereafter explained.

The slots 19-20 act as guiding and holding means to hold the gear d in the proper pitch relation to the driving and driven gears as the gear d is being shiftedandwhen it is stationary. The angular portion of the slot 19 may be dispensed with and the teeth of the gear d allowed to bottom on the teeth of one of the other elements as it is movingon the spiral gears, the gear d being moved laterally by the contact with the said ele- During the shifting of the gear d, it is not absolutely essential that the gear be in the proper pitch relation, but during the period when it is held stationary and in mesh with the cylindrical gears some means as the slots 20 should be employed to position the gear properly between the engaging gears, so that the teeth of the gears will mesh properly. The slots 19-20 therefore act to position the gear at laterally so that the teeth mesh properly.

As there are three points or stations on the gears ab where variation in, speed takes place and to which the gear d must be set, the grooves-where there are top and bottom guides at m" employed, as in Fig. 1,--'

are composed of angular members 19 alternating with longitudinal members 20 standing parallel with the axis of rotation.

If the driving-gear a had motion always in the same direction, and did not require to be reversed, there would be no tendency on the part ot the driver to lift the gear d;

and the top-guide m would. not be required, and that guide could be dispensed with also by turning the ends 22 of the box 14 under the sides of the fixed bottom guide we", as indicated in Fig. 4. The carrier 15 may be controlled in that way by a single guide, in the place of the double guides shown in Figs. 1 and 2. In addition to this guiding means, provision is made for controlling the gean carrier in its movement longitudinally and also for moving it automatically in time with the revolutions of the driving and the driven elements whereby the gear (Z will be kept continually in mesh and in working position both when in engagement with a cylindricalsgear element and also when traveling on a spiral-gear element.

As the construction ofthe gear a and also of the gear I) requiresthe gear (1 to have a limited lateral movement in order to properly engage and mesh with the cylindrical gears, it becomes necessary to provide for the lateral movement of the gear cl as is evident from the fact that the driving gear a is composed of spiral gears and cylindrical gears of increasing diameters; and provision is made to that end by placing the gear d in a laterally movable-box 1 1 on the carrier 15, the box 14 being fitted to slide on guides 16 on the sides of the carrier 15, as seen in Fig; 7. The means for moving the gear car rier 15 longitudinally maintains that part in motion in time with the gears a-b, and also arrests the movement at the proper time to place the geard in working position with the cylindrical gear on passingoff the spiral.

The construction .and operation of the means for moving and controlling the gear (I will he described with reference more par ticularly to Figs. 1, 2, 3, 5, 6, 7 and 8. The shifting cam s has two helical grooves t-u on its periphery which begin and terminate in circular portions at both ends, the groove 25 being spiral except at the

ends

27 and 28 where it becomes not only eccentric to the axis, but also decreases in depth so that the bottom of the circular portion terminates on the circumference of the cam. The other groove it begins at a point 29 in the middle and extends around the circumference of the cylinder in a similar manner to the first mentioned groove and terminates in a circu lar portion 30 at the opposite end.

In the drawings I have shown the shifting eam s mounted on a separate shaft and connected to the drivin element by means of the gears 80-81, but it is evident that the cam 8 could be mounted on an extension of the shaft on which the driving gears are arranged, and the intermediate gears 80-81 dispensed with.

The shifting cam s and the driving gear a are positively connected by means of the gears 80--81, and when these gears are of equal sizes, as shown, both parts rotate at the same speed. The size of the teeth on the gears are the same and the number of teeth on the spiral gears 5-6 are the same, therefore, since the diameter of gear 6 is greater than gear 5, the angle subtended by ear 5 must be greater than the angle subten ed by gear 6. Therefore, the driving element a turns through a less angle to move the gear,

(1 over the spiral 6 than it does to move the gear over the spiral 5.

As the cam 8 moves uniformly with gear a, it is evident that the slope or slant of groove a must be greater than the slope of groove t to properly move the gear (I. By reference to the drawings Fig. 2, it is seen that the gear 6, from the point where it be ins to diverge from gear 4 to the point where it enters entirely into gear 3, occupies about 1%- circumferences, and the gear 5 measured from the corresponding points on

gears

4 and 2 occupies about 2% circumferences. Therefore, the groove 14 mustbe formed on such slope that the gear d will be moved from mesh with gear 4 to mesh with gear 3- in 1% revolutions of the cam s, and groove t must be formed on such slope or slant that ear d will be moved from ear 3 to gear 2 1n 2;} revolutions. As the distances between the gears 22- are equal, the slope of groove 24 must be greater than the slope of groove t.

Also the slope of the groove is not constant due to the fact that when gear d is on the spiral gear, the diameter of the spiral gear is varying and the angle subtended by each tooth is varying, thereby varying the spacing of the teeth about the center. A bar 31 attached to the gear carrier 15 at one end 32 is connected by a loose joint 33 to a slideblock 34, in which is a pin 35 loosely fitted for movement longitudinally to a sufficient extent to set the pin into the cant groove when the pin is caused to project; or to disengage it from the cam when the pin is drawn back.

As. the gears a-b have three cylindrical gear elements with which the gear at may be set in line, the means for moving and setting the gear-carrier 15 is required to have three points of rest in the length of the complete throw on longitudinal movement along the bars ab, namely, one at the gear 2, another at the gear 3, and a third at the gear 4 in the driving element a. The cam 8, therefore, must have four points where the pin 35 engages the rooves and also leaves the grooves at the end of its traveland at these points or portions the pitch of the grooves changes from the helical to a circular direction at right angles to the axis of the cam. The forward movement of the pin to engage the grooves is effected by hand through means so controlling the pin 35 that a forward movement of the pin can not take place at any other period in the revolution of the cam at the point where a circular terminal portion of the groove comes in line with the pin. This will be understood from Fig. by imagining the gear-carrier as standing at rest on the end of the guides m next to the change cam s, and the gear (I as being in mesh with the smallest cylindrical gear 2 of the driver a and the largest gear 4 of the driven element 6.

With the gear cl set to that position the gear 2 will make two revolutions to one revolution of the gear 4",--and as the cam being actuated from the driving element a throu h the gears 8081 revolves in time with t e driving element, the points on the cam at which the pin 35 if set forward could engage the cam will come in line with the pin twice in every revolution of the gear 4*. But as the gear 03 cannot properly be shifted from the gear 4 to the adjoining spiral excepting at the point where the widening face begins,-namely, at the point m Fig. 4-it is necessary to prevent the gear (Z from being moved longitudinally at any other period in the revolutions of the gears 2- 1 than at the point where the faces of the gears increases in width. The carrier 15 then being moved longitudinally in the propel time with the revolution of the gears 2-4" the gear (Z is transferred from one set of cylindrical gears to the next by traveling y on the spirals. Should the gear a? be caused to move off the cylindrical gears at any other period in the rotation of the gears 2-4 than when the widening faces are in line with the gear d as above described, the gear would not enter on the spiral element 6*, but on the contrary it would be thrown out of gear and be disconnected from the driving gear.

At the points of transfer on the gearsa-J2' where the cylindrical gear and the spiral gear join or merge one into the other, one or more of the teeth of one element will enter into the formation of the other joining element, and the teeth of the cylindrical element are therefore of uniform width. to the point of divergence m, but from that point they increase in width until the teeth on the widening portion 3/ of the gear correspond in width to the sum of the widths of the cylindrical and spiral elements. This widening-face is of sufiicient width to keep the gear d in mesh with the gears while moving parallel with the axis of rotation.

The means for moving the gear cl longitudinally in time with the rotation of the gear 6 and for controlling such movements includes the feature of locking the gearcarrier 15 whereby the gear d will be held in working position, between the driving and the driven elements wherever it maybe set,- also, of shifting the carrier from one Set of cylindrical gears to another from the rotary motion of the driving or the driven elements; also of throwing off or disconnecting the carrier from the-cam directly by the cam itself. These features will be described with reference to Figs. 2, 3, 5, 6, 7, and 8. The slide-block 34 movable in the guideway 37 carries a pin 35 that is loosely fitted to move inthe slide, and projecting from it when pressure is applied against its head 36.

As the pin 35 exceeds in length the depth of the guide-way it will take the cam-groove when the head 36 is against the stationary back-rail 38 of the guide-way. Or, on the other hand, the pin will clear the cam-groove when the head of the pin is set in one of the recesses 40-4142 in the back-rail. The lastnamed recesses are in line with or directly opposite the terminal ends 27-28- 2930 of the cam-grooves, and in each recess is a slide-bolt 43 loosely fitted in a slot or opening in the back of the recess with its end in such relation to-the head of the pin '35 that on being pressed forwardv thebolt will force the head of the pin out of the recess and set its forward end into that one of the grooves of the cam with which'the pin may be in line at the moment of operating the bolt. In one position the pin 35 will lock the slide 34 and keep it from moving in either direction'in the 'guideway; and in the other position it will connect the slide 34 with the cam s.

Loeenoe In the present construction of the setting mechanism there are four points on the periphery of the cam arranged to take the cam-grooves, namely, one at each end of the two separate grooves, and at those points each roove isgradually reduced in depth tower the terminal end by gradually raising the bottom so that it terminates flush with the peripheral surface. These portions of decreasing depth are at the outer ends 27-30, but the remaining ones 28-29 are situated directly opposite each other in the middle of the cam where they lie in a common plane at right angles to the axis and are separated by an elevated ridge, p on the periphery. The pin 35 on taking the groove't at one end will be ejected on arriving at the opposite end according to the direction in which the cam 8 may M turning, or it will take the cam groove 14 at one end and be'ejected from that groove on reaching the opposite end. The separation of the pin 35 from the cam is thus produced automatically by the cam itself.

The bar 45 carrying the slide-bolts 43 is movable in an are behind the back-rail of the guide-way, with an extent of throw sufficient to set the bolt against the pin 35 by a single throw of the hand-lever 50. The sidemembers 4647 carrying the cross-bar 45 are movable in a limited are on the pivot 58 by the hand-lever 50 that is connected to the bar by a link 54. But instead'of being directly attached to the hand-lever, the bar 45 is connected with it in such manner that by the initial movement of the lever sufficientpower is stored up in a sprin 55 to impart to the bar 45 a quick throw orward' at the moment that the spring when under compression is allowed to act on the bar 45. The spring is interposed between the bar 45 and the lever 50, as seen in Figs. 5 and 8, and its .compremion is effected by rarily locking the rocking-frame. This is done by a hook 57 on the frame and a latch 59 on a fixed post 60, which by engaging the hook holds the rockin frame stationary when the hand lever is thrown toward the frame, and then releases it and allows the spring to act on the frame as soon as the hand lever strikes the toe of the latch.

The advantage of throwing the pin 35 in operative position by the reaction of the spring, or by some like means, instead of directly by thelever, is that the pin 35 will be set by a quick throw out of the recess in the stationary back 38 of the guide-way and caused to take the groove in the camat the moment that the groove comes in line with the pin. a

In the machine represented in Figs. 1 and 2 the driving element has two revolutions to one revolution of the driven-element b,

when the parts are connected as before described, and it is necessary to prevent the tempowhere the pin 35 is gear d from being set off the ear 4* except at the one point in the revo ution of the driven-element where it will run on to the spiral. The lever is therefore controlled in its movement by a locking-out mechanism that prevents the pin 35 from taking the cam-groove at any other period in the revolution of the cam than where the switching or transfer of the gear (l from the cylindrical gear 43 to the spiral gear takes place. In this lock-out means a lever composed of a short member 61 and a long member 64 at right angles has a limited movement in a vertical plane on its fulcrum 63 with the bottom edge of the toe 62 on the end of the short member lying over the end of the arm 65 and in such relation thereto that it will prevent the arm 65 from raising as long as the longer'member 64 of the lever is held up. That longer member of the locking-out lever extends over and in line with the shorter member of a lever 70 of the first order, the fulcrum 71 of which is carried by a slide-block 68. The end of the shorter member of the last named lever lics directly under a disk-cam 74 fixed on the axis 9 of the driven-element b and hav ing for one half of its circumference an acting-rim or edge of constant radius with the remaining portion cutaway or reduced, as from o to c, Fig. 8. This cam revolving in time with the gear I; acts to hold down the arm 70 of the controlling lever during one half the complete revolution of the gear and allows that lever to rise during the re maining half-revolution, during which'period in the motion of the gear I) the controlling lever will offer no resistance tothe downward movement of the longer member of the locking-out lever; and that lever will be free to drop and release the rockingfranie carrying the slide-bolts. Such control of the pin-setting means whereby the pin is caused to engage the cam leaves the pin free to take the cam-groove with which it is standing in line when the gear 03 is in working position between the driver 2 and the gear a". Whereas, in the other positions of the gear 03 at any other point along the driving gear a than between the gears 2 and t the block 68 that carries the fulcrum 71 is at rest at the bottom of the slot 69 and the locking-out lever remains out of action until its fulcrum point 71 is again elevated. By its position in the slot 69 this fulcrumblock controls the locking-out lever. It is in turn controlled, however, by the carrier 15 by which it is raised and held up when the carrier is at rest between the

gears

2 and 4=,but it is dropped as soon as the carrier is moving to transfer the gear d. This raising and droppin of the fulcrumblock 68 in the slot 69 is e ected by a wedgeshaped toe 76. on the front of the carrier so arranged that its pointed end will pass under and lift the fulcrum-block as often as the carrier is drawn to the front end of the guides; or the fulcrum block will drop and assume its position at the bottom of the slot 69 when the lifting wedge 76 is withdrawn by the return movement of the carrier. Thus with the fulcrum 71 raised the shorter arm 72 of the controlling lever cannot drop as long as the semi-circular portion of the cam 74 is turning against the longer member 70; but when the cam in its further rotation allows the end 70 of the lever to rise its opposite end will drop and release the locking-out lever, whereupon the shorter member 61 of that lever will release the arm as the rocking-frame is set forward by the hand-lever.

The cam 74 is so formed that it will hold down the arm of the controlling lever during one half of the revolution of the driven element 6, but in the remaining half revolution the lever 70 will be free to rise,

and will offer no resistance to the downward movement of the longer member 64 of the look-out lever. The locking-out lever as controlled in this manner and by the carrier 15 will be operative when the gear at is in working position between the driver 2 and the gear 49 but it will be inoperative in the other positions of the gear d along the driving-gear when it is not necessary to control the operation of the speed-changing means.

The locking-out operation as above described being required in the present construction of the mechanism only during the period when the carrier 15 is at the front end of the guide-way and the gear d is working between the driving-gear 2 on the one element and the driven gear 1* on the other element, the lever 70-72 will remain at all other times in the position shown in Fig. 3, with the fulcrum-block 68 at the bottom of the guide-slot 69. In that POSI- tion the toe 62 on the lockingout lever will be clear of the arm 65 and the frame or part carrying the bolts can be actuated by the hand-lever 50. It is only when the fulcram-block 68 is raised and held in elevated position that the locking-out lever is brought into play. When the driven gear has less than three cylindrical gear-elements, the locking-out means above described is not required.

Fig. 9 illustrates a variable-speed mechanism in which the driven element 1) in the construction shown in F ig. 1 is dispensed with and the gear d constitutes the drivenelement. In this modification the power is applied to the driving gear a" through the shaft 90, and is transmitted through the gear wheel (l to the shaft 116. The connection between the shaft 116 and the gear cl" is made by a jointed shaft having a slidable connection 121--122 with universal joints 118-119 that provide for both the longitudinal movement of the gear d", and also for the lateral movement of that ear which is required on account of the di erence in the diameters of the cylindrical gears and in their connecting spirals on the driver elements.

The gear a?" is adjusted longitudinally for changing the. speed of the driven part by connecting the gear carrier 15 with the speed-changing means before described, but in this modification, however, the cam s and the coa'cting parts are situated on the end of the machine opposite to that where the driven shaft is arranged; and the journalbearings for the cam s are situated on the frame along side of the box for the driving shaft 12. The connecting rod 31 is attached to the right side of the gear-wheel carrier 15*, as seen in Fig. 9. This construction will be found of advantage for transmitting power from a driving-shaft to a driven shaft with varying conditions of speed in operating light machinery. For heavy work, however, or where the angular position of the driven shaft would be an objectionable feature in the mechanism, the

two gears a--b are substituted.

The short shaft on which is fixed the gear (5", is connected by universal joints 118-119 with the sleeve or tubular section. 121, in which the square-end portion 122 of the shaft 116 is fitted to slide but not to turn.

This extensible section permits the necessary longitudinal movement of the gear d" from one end to the other of the driving element a". The gear-carrrier 15 is retained in working relation to the driving-element a in the longitudinal and lateral movements by slotted guides, the same as in the machine represente in Fig. 1.

This mechanism in which I have embodied my invention is adapted to give motion to a shaft or part to be driven at difierent rates of speed, according to the variations in the sizes of the cylindrical gears; but the motion imparted to the driven part will be only in one direction. By providing a reversinggear between the driving element a and the shaft from which the driving-power is taken, the motion is controlled in direction and is readily reversed at will. The reversing gear illustrated in Fig. 1 as combined with the variable-speed mechanism of my invention contains several novel features. It is adapted by its construction to act first after the manner of a friction clutch, as it begins to take hold, and afterward it locks or connects the parts together in a positive manner. The parts or members of this lutch as seen in the details Figs. 11, 12, 13 and 14 comprise a male clutch member 97 fixed on a sleeve 102 that is connected by spur-gears 91-93 with a spindle or short shaft 90. The spindle is connected with the shaft 1 of the driving gear a, by the spur-gears 91-92, of which pair the gear 92 is fast on the shaft of the gear a. The other male member 99 of the clutch is on the end of a sleeve 101, to which is connected the spindle 90 by three gears 94.-95-96, so as to transmit motion to the spindle in the reverse direction.

Between the-two clutch-members 979,9 the slidable female member 100 turns with but is arranged also to slide on the squared portion 112 of the shaft 12, with an extent of movement sufficient to set the slidable member 100 clear of one of the clutch-members 97'99 and in engagement with the other clutch member at the opposite end, according as the member 100 is shifted in one direction or the other.

The clutch members 97-99 have conical sides and a flat head or end on which are radial ribs ,or lugs 108 corresponding in number and arrangement with similar ribs or projections 106 in the recesses 105 on the ends of the slidable member 100; the last named projections are situated on the bottom of the recess or cavity 105 in each end of the slidable member. .These parts, 106108, constitute the interlocking means the female member 100 is positively connected to it. The conical faces of the male and female members are adapted by their shape and fit to form a friction clutch; but in addition to these frictional surfaces the female member of the clutch is provided with yielding catches 103 that engage the male members before the positively locking ribs or projections come together. These yielding catches at the moment of contact-between the two clutch-members act to set up an initial resistance by gripping the rim of the opposite conical member over which they are pressedand this engagement of the parts takes place before the slidable member 100 interlocks positively with the male member against which it is pressed.

The catches 103 consist of yielding tongues each secured atone end in a recess and terminating in an angular hook 104 on the outer end. The angular faces of the hooks 10 1 correspond in inclination to the also extend beyond the end of the sleeve of the clutch, as seen in Fig. 12, by virtue of which they come in .contact first with the conical sides of the male-member against which they are pressed, and then ride over the conical sides of the male clutch member, before the positivel locking-members of the clutch are broug it together. The friction thus set up between the slidable member of the clutch and the male-member sets the driven part in motion before the members of the clutch are positively coupled,

whereby the male member when seated in.

faces of the conical clutch-member, and they thereby reducing the shock incident to the sudden coupling of the two members through the positively clutching means.

The clutch 1-16 is provided between the shaft 114 or part being driven and the gear b as seen in Fig. 1, when it is desired to connect or disconnect the power during the periods of reversing the direction of the motion, and at other times when necessary.

I claim:

1. In a variable speed gearing the combination of a driving element comprising alternately arranged cylindrical gear-elements and spiral gear-elements on a common axis, a driven clement adapted to move on lines parallel with the face of the cylindrical gear elements and oblique to the face of the spiral gear element when moved longitudinally of the driving element, and means for adjustably moving the driven element on said lines;

2. A variable speed gearing including a driving element composed of alternately arranged cylindrical gears and spiral gear-elements on a common axis, a shaft driven thereby arranged for rotation parallel with the axis of the driving-element, a cylindrical gear connecting the said driven-shaft with the driving-element, and means operating to move said driven element longitudinally on lines parallel with the face of the cylindrical gear elements and oblique with respect to the face of the spiral gear elements.

3. A variable speed gearing including a driving element composed of alternately arranged cylindrical gears and spiral gearelements on a common axis and a shaft to be driven thereby; a driven element comprising a cylindrical gear connecting the shaft driving element with the shaft to be driven and means operating to shift said driven element longitudinally on lines parallel with the face of the cylindrical gears and oblique with respect to the face of the spiral gears of the driving element.

4. In a variable speed gearing the co1nbination of a driving element having cylindrical gears and spiral gears, a driven element having like cylindrical and spiral gears oppositely arranged with respect to the gears of the driving element, mechanism connecting the driving and driven elements, said connecting mechanism being movable longitudinally and transferable from one position to another 11 on said driving and driven elements while eing in continual engagement therewith.

5. The combination of a driving-element havingcylindrical gears and spiral gears alternately arranged on a common axis, a driven element havin cylindrical gears and spiral gears oppositely arranged on a separate axis, mechanism connecting the driving and driven elements and in continual engagement with both ele1nents,said connecting mechanism being movable longitudinally of said driving and driven elements, and means for controlling the said Inechanisin in such movement.

(5. A variable speed gearing having a driving-element comprising cylindrical gears of different diameters and connecting spiral gears alternately arranged on a common axis, a driven element comprising cylindrical gears and connecting spiral gears corresponding to the gears of the driving-element and oppositely arranged with respect to those gears, mechanism connecting said elements arranged for movement longitudinally and also laterally of the said driving and driven, elements, means for controlling the said mechanism in its longitudinal movement and means for controlling its late -al movement.

7. The combination of a driving-gear having cylindricabgear elements of different diameters and connecting spiral-gear elements alternately arranged for rotation on a common axis, a driven gear having cylindrical gear elements and spiral-gear elements arranged in opposite position with respect to the corresponding elements of the driving mechanism, gear connecting the said driving and driven gears, means for moving the connecting mechanism longitudinally of said gears and means for controlling the movement of said connecting mechanism laterally during its longitudinal movements whereby it is maintained in continual engagement with both elements.

8. In a variable speed gearing a drivinggear comprising alternately arranged cylindrical gear elements and spiral-gear elements, and a driven gear comprising cylindrical gear elements and spiral gear elements, oppositely ar "angcd with respect to the corresponding gear-elements in the driving-gear; in combination with connecting means between said driving and driven gears movable longitudinally of said gears and also laterally with respect to the axis of rotation, and means for maintaining the said connecting means in continual engagement with the driving and driven gears during its longitudinal and lateral move ments.

t). The combination of a driving-element having cylindrical gears of.difi'erent diameters and spiral gears connecting the cylindrical gears in series on a common axis, a driven element having corresponding cylindrical gears and spiral gears arranged in opposite position with respect to the gears of the driving element, a cylindrical gear between said driving and driven elements and adapted to operativcly connect the same in continuous gear with each other, and means for moving the cylindrical gear longear connecting the driving-element and the driven-element, means for moving the said gear in time with the revolutions of the driving and driven elements, means for controlling the lateral movement of the cylindrical gear, and means for reversing the rotation of the driving-element. I

11. In a variable speed gearing the combination of a driving-element comprising cylindrical gears of difierent diameters and intermediate spiral gears on a common axis connecting the cylindrical gears, a drivenelement comprising cylindrical gears and spiral gears on a separate axis arranged in opposite position to the gears of the drivingelement, a cylindrical gear connecting the driven element with the driving-element, means for moving the said gear along the driving and driven element and means for maintaining it in continual engagement with both elements during suchmovement.

12. In a variable speed gearing the combination of a driving element composed of alternating cylindrical gears and spiral gears on a common axis, a driven-element composed of corresponding cylindrical gears and spiral gears; connecting mechanism between the said driving and the driven element, a slidable carrier for said connecting mechanism, and means for moving the slidable carrier longitudinally of the said driving and driven elements and in time with the rotation of the same during the period of the engagement of the said connecting mechanism with the spiral-elements.

13. In a variable speed gearing the combination of a driving element having alternately arranged cylindrical gears and spiral gears on a common axis, a driven-element having correspondingly arranged cylindricalgears and spiral gears, a cylindrical gear engaging the driving and the driven elements, a movable carrier in which the said cylindrical gear is movable laterally, means for moving the said carrier longitudinally of the driving and the driven elements, and means for controlling the lateral movement of said gear in its carrier.

let. In a variable speed gearing the combination of a driving element including cylindrical gears of different diameters and intermediate spiral gears; a driven element including cylindrical gears and spiral gears corresponding to those in the driving element and oppositely arranged with respect thereto, the teeth of the cylindrical gears and the spiral gears in both elements being parallel with the axis of rotation; a carrier between the driving and the driven element movable longitudinally thereof, a cylindrical gear rotatable in said carrier and having limited lateral movement therein, means for controlling the said carrier longitudinally, whereby it is shifted from one cylindrical gear to another on the driving and the driven elements, and means for controlling the lateral movement of the gear in its .carr1er.

15. The combination of. the driving-element, the driven-element, the slidable carrier movable longitudinally of said driving and driven elements. a laterally slidable box on the said carrier, a gear mounted for rotation in said slidable box connecting the driving. and driven elements, and means for shifting the said carrier along the driving and driven elements in time with the rotation of said elements, whereby the said connecting gear is kept continually in mesh with the driving and driven elements, substantially as set forth.

16. In a variable speed gearing the combination of a driving-element comprising cylindrical gears of difl'erent diameters increasing one over another on a common axis and spiral gears connecting the cylindrical gears in series, a driven-element comprising cylindrical gears and spiral gears oppositely arranged on a separate axis, a cylindrical gear connecting the driving and driven elements, means for holding said connecting gear in operative relation with any given set of the cylindrical gears in the driving and driven elements, means operating to move said cylindrical gear longitudinally of the driving and driven elements in time with the revolutions of said elements, and means for reversing the direction of rotation of the driving-element.

17. In a variable speed gearing the combination of a driving-element having alternately arranged cylindrical gears and spiral gears on a common axis, a driven-element comprising a gear movable longitudinally of the driving-element, means operating to v nately arranged cylindrical gears and spiral gears, a driven element comprising a gear mounted for rotation on an axis parallel with the axis of rotation of the driving-element and movable from end to end of said driving element; means for holding the said element in position at any given one of the cylindrical gears on the driving-element, means for adjusting said driven-element longitudinally on the driving-element, and means positively connecting the driven-element in its varying positions with the part to be driven.

19. In a variable speed gearing the combination, of a drivingelement comprising alternately arranged cylindrical gears and spiral gears on a common axis; a driven element comprising a cylindrical gear mounted for rotation on an axis parallel with the axis of the driving-element, and means for maintaining the driving-element in continual engagement with the driven-element in all its varying working positions and move ments thereon, comprising a longitudinally movable carrier, a su port thereon for the axis of the driving e ement having lateral movement in said carrier, means actuated from the driving-element for moving said carrier longitudinally of the driving-elc ment and means for controlling the lateral movement of the driven element.

20. In a variable speed-gearing, a shifting cam having a groove, a portion of which is helical, the end port-ions being straightened and terminating eccentrieally and at the circumference of the cam, in combination with a cooperating pin standing in position for operatively engaging the cam but normally out of engagement therewith and means for setting the pin to engage the cam.

21. In a variable speed-gearing, a rotatable shifting cam having a helical groove provided with circular portions at the ends, the ends of the circular portions being eccentric with relation to the axis of rotation and terminating on the circumferential surface of the cam, a cooperating pin normally out of engagement with the cam, but movable in a right line toward the cam, and means for setting said pin into engagement with said circular portion in advance of its engagement with the helical groove, and means for holding said pin against said surface in the rotation of the cam.

22. In a variable speed-gearing, a rotatable shifting cam having a helical groove terminating in circular portions which terminate eccentric to the axis of rotation, in combination with a cooperating pin connected with the part to be shifted normally out of engagement with the cam but movable in a right line perpendicular to the surface of the cam, and means for setting said pin in operative relation to the circumferential surface of the cam to engage said terminals of the groove,and means for holding said pin in engagement with the cam in the rotation thereof.

23. In a variable speed gearing, a driving element, a cylindrical cam operatively connected therewith, said cam having a plurality of spiral grooves on its circumference, each groove being generally concentric with the axis of rotation and having circular terminals, said circular terminals terminating eccentrically to the axis, whereby each groove terminates circumferentially of and at the surface of the cam, in combination with a cooperating pin adapted to move along the face of the cam longitudinally of the axis of rotation, and also movable in a right line perpendicularly to the surface of the cam, means for settin said pin in operation relative to the sur ace of the cam to engage said circular terminals, and means connecting said pin with the part to be shifted.

24. In a variable speed gearing, the combination of a driving gear having alternately arranged cylindrical gear elements and spiral gear elements on a common axis, the teeth of said gear-elements being parallel with the axis of rotation; a driven gear arranged for rotation on an axis parallel with the axis of the driving-elements, means for changing the working position of the driven-gear from one to another of the gear-elements in the driving gear and maintaining the said driven gear in continual mesh therewith, comprising a slidable carrier, a support thereon for the driven-gear, means for moving the carrier longitudinally along the driving-gear in time with the revolutions thereof, means operating to ar: rest the movement of the carrier when the driven-gear comes in working position with relation to a cylindrical gear element on the driving-gear, and means for reversing the direction of the longitudinal movement of the carrier.

25. In a variable speed gearing the combination of a driving-gear having alternately arranged cylindrical gear elements of different diameters and spiral-gear elements, a driven-gear having cylindrical gear ele ments and spiral-gear elements correspondingly arranged, a connecting gear between the driving and the driven elements in continual mesh therewith, means operating to change the working position of the said connecting gear, comprising a longitudinally movable carrier in which the connecting gear is adapted to rotate and to have limited lateral movement, means for controlling said lateral movement, means for moving the carrier longitudinally in time with the revolutions of the driving-element, and means for reversing the direction of such movement.

26. In a variable speed gearing, the com bination of a driving-element, a driven-element, a'connecting gear between the said elements, a slidable carrier movable longitudinally of the said elements, and in which the said gear is mounted for rotation, means for shifting the carrier along the said elements in time with the revolutions of the elements, and means controlled by one of the said elements, operating to prevent the said shifting means from acting on the gear-carrier excepting at that period in the revolutions of the driving and driven elements when the points of change in both elements where the said gear is transferable are in position on opposite sides of the said gear.

27, In a variable-speed gearing the combination of a driving-element, a driven-element, connecting mechanism between said elements, movable longitudinally of the said elements, means operating to shift the said mechanism longitudinally of the elements, for changing the Working-position of the said mechanism, and a locking-out device controlled by one of said elements and adapted to prevent the said mechanism shifting means from operating excepting at periods in the revolutions of the driving and driven-elements when the points of change on both the driving and the driven elements are in position on opposite sides of the connecting-mechanism.

28. In a variable-speed gearing the combination of a driving-element, a driven-element, and a connecting gear between said elements and movable longitudinally thereof, and means for shifting said gear on the driving and driven elements comprising a spirally grooved shifting cam, a slide, a pin carried by the slide, operating in one position to engage the cam-grooves and in another position to set clear of the cam grooves, means connecting said gear with the pin, means for setting the pin in position to engage the cam, and means operating to control the said setting-means whereby the same is prevented from shifting the gear on the driving and driven elements excepting at the period in their revolutions when the change-points on both elements are inline with said gear,

29. In a variable speed gearing, a driving element composed of alternately arranged rotatable cylindrical gears and spiral gears on a common axis, a shaft laterally movable with respect to the driving element, a cylindrical gear on said shaft connecting it with the driving-element, means for moving said connecting gear longitudinally along the driving-element, means for moving the said shaft laterally with respect to said driving element, and means directly connecting the said shaft with the part to be driven.

noeaaoa 3O. In a variable speed gearing, the combination of a driving-element, a longitudinally movable liven-element, a grooved rotatable cam, a lever, means operated by lever for connecting the driven element with the cam to move said element, and means brought into action by said lever operating to set the connecting means into the groove of the cam.

31. In a variable speed gearing the combination of a driving-element, a longitudinally movable driven element, means for connecting said driven element with the cam, including a movable cooperating pin,

connecting means between said pin and the driven-element, a lever, means actuated by said lever for setting the said. pin in operative position with relation to the cam, and meansbrought into action by the movement of said lever operating to set the pin into engagement with the groove of the cam.

32 In a variablespeed gearing the combination of a driving-element having alternately arranged cylindrical gears and spiral gears, a driven element comprising a gear mounted for rotation on an axis with the axis of rotation of the driving element and movable from end to end of said driving element; means for holding the said element in position at any given one of the cylindrical gears on the driving element, means for adjusting said driven-element longitudinally of the driving element, and means for reversing the direction of rotation of the driving element.

33. In a variable speed gearing, a cam having a groove, the central portion of said groove being angularly arranged with relation to the axis of the cam, and the end portions of'the groove being parallel to a plane perpendicular to the axis of the cam and terminating eccentrically and at the circumference of the cam.

84. In a variable-speed gearing the combination of a driving-element, a driven-element, and a connecting gear between said elements and movablelongitudinally thereof, and means for shifting said gear on the driving and driven elements comprising a spirally grooved shifting cam, a slide, a pin carried by the slide, operating in one position to engage the cam-grooves and inanot-her position to set clear of the cam grooves, means connecting said gear with the pin, means for setting said pin in position to em gage the cam and means for moving the pin out of engagement with the cam,

35. In a variable-speed gearing a drivingelement having alternately arranged cylindrical gear-elements and spiral gear-elements on a common axis, a driven element adapted to engage the gears of the driving element and a cam having a helical groove adapted to move the driven element longitudinally parallel said to contact with the various gears of the driving element.

36. In a variable speed earing, a drivingelement having alternate y arranged cylindrical and spiral gear-elements on a common axis, a driven shaft, a cylindrical gear connecting the driven shaft with the drivin element and cylindrical cam having a helica groove adapted to move the connecting gear along the driving element in time with the rotation of the same.

37. In a variable-speed gearing of the type described, a lon 'tudinally movable element, a grooved shi tin cam, means for connecting the movable e ement with the cam, the cam being formed so as to throw the connecting means out of operative relation with the cam.

JAMES ARNOTT.

Witnesses:

E. E. Osnomv, M. REGNER.