US2803141A

US2803141A - Multi-speed drives for phonograph turntables

Info

Publication number: US2803141A
Application number: US256290A
Authority: US
Inventors: Herbert L Hartman
Original assignee: GEN IND CO
Current assignee: GEN IND CO; GENERAL INDUSTRIES Co
Priority date: 1951-11-14
Filing date: 1951-11-14
Publication date: 1957-08-20
Anticipated expiration: 1974-08-20

Description

Aug. 20, 1957 AN 2,803,141

MULTI-SPEED DRIVES FOR PHONOGRAPH TURNTABLES Filed Nov. 14, 1951 4 Sheets-Sheet 1 INVENTOR. p L m HIS A TTOP/VE rs.

Aug. 20', 1957 HARTMAN 2,803,141

MULTI-SPEED DRIVES FOR PHONOGRAPH TURNTABLES Filed Nov. 14, 1951 4 Sheets-Sheet 2 YINVENTOR.

BY W* Aug. 20, 1957 H. 1.. HARTMAN 2,803,141

MULTI-SPEED DRIVES FOR PHONOGRAPH TURNTABLES ,Filed Nov. 14, 1951 4 Sheets-Sheet s IN V EN TOR.

Aug. 20, 1957 H. HARTMAN Q MULTI-SPEED DRIVES FOR PHONOGRAPH TURNTABLES Filed NOV. 14 1951 4 Sheets-Sheet 4 INVENTOR.

BY W W) 2,803,141 Patented Aug. 20, 1957 MULTI-SPEED DRIVES FOR PHONOGRAPH TURNTABLES Herbert L. Hartman, Elyria, Ohio, assignor to The General Industries Company, Elyria, Ohio, a corporation of Ohio Application November 14, 1951, Serial No. 256,290 15 Claims. (Cl. 74-200) My invention relates to selective inulti-speed drives for phonographs and more particularly to a unitary change-speed frictional drive mechanism having a final drive pulley wheel which is adapted to be selectively driven at different rotational speeds, and whose peripheral rim is adapted to be applied to a phonograph turntable support tofrictionally drive the turntable.

More specifically, my present invention involves a drive mechanism of the above class and comprises a motor pendantly supported by a common frame for all parts of the mechanism, said motor affording a drive shaft which comprises an upwardly extending end portion which is diametrically stepped to provide a series of pulley portions of different diameters and wherein a plurality of idler pulleys are adapted to be interchangeably laterally moved to an operative position to be frictionally driven by different of said pulley portions, and in turn to frictionally drive a final drive wheel which is adapted for peripheral engagement with an annular pendant flange of a phonograph turnable, whereby the rotational speed of said turntable may be selectively varied by selectively moving an appropriate one of said idler pulleys to the aforesaid operative position of engagement with its associated driving step of said motor shaft.

The mechanism of my invention, therefore, involves improvement over that type of change-speed turntables driving mechanisms as that which is disclosed in the prior United States Letters Patent No. 2,438,265 to Robert G. Metzner wherein the rotational speed of a turntabledriving idler wheel is selectively varied as a result of vertical adjusting said wheel to the different levels of a plurality of motor shaft steps, and at the same time my invention involves improvement over that type of phonograph turntable drives which isdisclosed in the prior Letters Patent to Paul Stead Gay No. 2,518,769, which involves the provision of a series of relatively laterally interspaced idler pulleys, each having a pair of vertically interspaced pulley portions whose diameters are in different ratios in the case of different pulleys of the series, and wherein the upper and lower idler pulley portions of each of said pulleys, when in an operative position of adjustment, are respectively engaged with the wheel periphery, and the said pulley portion of a motor shaft, said pulleys being adapted for processional adjustment movements to and from such an operative position.

The mechanism of this invention, therefore, involves the use of a stepped motor shaft in combination with a series of laterally interspaced pulley elements each of which is adapted to be interchangeably frictionally engaged with a different step of a diametrically stepped motor shaft and for concurrent frictional driving engagement with the idler wheel, in response to lateral processional adjustment movements of all of said idler pulleys, whereby greater simplicity of design and operation, a lower cost of production, and a high degree of reliability of eflicient operation, is realized.

An object of my invention, therefore, is to-provide an. improved selective change-speed friction drive for flanged type phonograph turntables which is simple in construction and which is reliably efficient in operation.

Another object of my invention is to achieve selective change-speed driving of a turntable friction drive wheel without the necessity of use of costly cam mechanisms to elevate or lower said wheel.

Another object of my invention is to achieve the benefits of the above objectives, in that type of mechanisms wherein a pluraliy of idler pulley elements are adapted for different lateral adjustments to select any one thereof to effect communication of driving motion from a motor shaft to a final drive friction wheel, in a structure wherein all pulley portions of each said elements are of like diameters.

Another object of my invention is to pre-select different rotational speeds of a final drive wheel of the mechanism by providing a motor shaft having a plurality of superposed pulley portions of relatively different diameters and a plurality of idler pulley elements, each being interchangeably movable to a like lateral position to frictionally engage and be driven by different of said superposed motor shaft portions.

Other objects of my invention are to provide an improved mechanism, wherein advantages of the aforesaid prior mechanisms are retained and disadvantages thereof are eliminated, and having the further advantages of greater simplicity and lower cost, over such prior mechanisms, as will be understood by those skilled in the art.

Different embodiments of the invention and the invention itself will be understood by reference to the drawings hereof, and to the following descriptive specification in which reference is made to said drawings, whereof- Fig. l is a view partly in plan and partly in horizontal transverse section of an embodiment of my invention as applied to a pendantly flanged phonograph turntable;

Fig. 2 is a plan view of the mounting plate for, and parts of the embodiments of Fig. l secured to said plate, no showing of the turntable and the final drive wheel being included herein, except that a segment of the turntable flange and the outline of said wheel, in operative positions, are indicated by dotted lines;

Fig. 3 is in part a section taken on the line 3'-3 of Fig. 1, the motor and motor shaft being shown in side elevation and the view showing one of two idler pulleys which is shown as having a lowermost, of a pair of relatively superposed pulley portions in its position of frictional driving engagement with a lowermost larger pulley portion of the shaft, and its 'upper pulley portion being engaged with the metal periphery of a duplex final drive wheel;

Fig. 4 is a view partly in section on the line 4-4 of Fig. 2, which is similar to the view of Fig. 3, except that the alternative idler pulley is herein shown as making frictional driving engagement by its single pulley portion, both with a relatively smaller upper pulley portion of said shaft and with the aforesaid metal periphery of the wheel;

Fig. 5 is a view partly on the line of section 5-5 of Fig. l, and being partly in side elevation, showing the utilization of an upper friction pulley portion of said idler wheel for driving engagement with an inner tubular surface of a pendant turntable flange;

Fig. 6 is a view taken as from the line of section 66 of Fig. 2, showing the spring biased laterally free floating carrier for the aforesaid idler wheel of Figs. 1 to 5 inclusive, together with the mount for said carrier all shown in side elevation with a portion of the supporting frame, only, being shown in section; v

Fig. 7 is atop plan viewof portions of the mechanism of Fig. l, with certain adjustable speed selector parts in an intermediate position, which is only assumed during move ment of said parts from one toward another operative posltlon;

Fig. 8 is a section taken on the line 88 of Fig. 7;

Fig. 9 is a plan view of the operating selector, adjustment lever, of the mechanism of the foregoing figures;

Fig. 10 is a plan view of the idler pulley carrier of Fig. 1, with a pair of idler pulleys journalled thereon;

Fig. ,11 is a section taken on the line 11-11 of Fig. 10;

Fig. 12 is a view generally of the nature of Fig. 1, showing a second embodiment of my invention adapted to drive a turntable at any of three rotational speeds.

In each of Figs. 13 and 14 there is shown, for the said second embodiment of Fig. 12, side-by-side views respectively of pulley portions of a three-stepped motor shaft, for each of three idler pulley elements, and of the associated duplex type of final drive pulley wheel, all of which are shown at their comparative relative operative levels;

Fig. 15 is of the general same nature of that of Fig. 13. but shows an arrangement of shaft and idler pulley elements suitable for use in connection with the morecommon simplex type of rubber treaded final drive pulley wheel.

Referring now to the disclosures by drawings hereof. Figs. 1 to 11 inclusive illustrate a first embodiment of my invention, the showing thereof being of a unitary motor drive mechanism which is adapted to drive a phonograph turntable 1, carried by, and being rotatable with a supporting post 3, journalled on a platform 2, at any of a plurality of speeds according to the selected position of a manually adjustable selector lever 4.

The aforesaid selector lever 4 is shown in one operative position of adjustment in Figs. 1 and 3 and in alternative operative adjusted position in Figs. 2 and 4. Although as hereinafter explained the mechanism of my invention is adapted to selectively drive the turntable 1 at any of more than two different rotative speeds, the embodiment of Figs. 1 to 10 inclusive is shown as adapted for either of two different speeds only.

The mechanism of my invention is unitarily carried by a mounting plate 12 by securing bolts 13 to an apertured supporting platform 2 for such a turntable as that at 1, to adapt the rubber pulley rim 7b of the final drive wheel 7 of the mechanism, for lateral pressure engagement with the inner surface of the pendant tubular flange 1a of such turntable to cause said turntable to be driven by the motor M, which is pendantly supported by the plate by means of screws 11, with the diametrically stepped upper end of the motor shaft 16 being projected upwardly through an aperture 14 of said plate. The plate 12 and platform 2 are relatively sound insulated by the interposition of rubber or like grommets 13a.

Whereas the drawings are intended to show a construction adapted to selectively achieve driving of a turntable such as that at 1, at two different speeds which are in the ratio of 33:45, such relative rotative speeds may be in variant ratios, the true ratio being determined by the relative diameters of the upper and

lower pulley steps

5 and 6 of the motor shaft 16, Figs. 1, 3 and 4, either of which are, at will, selectively effective to frictionally drive a different one of the pair of idler pulley elements Which are respectively and generally indicated by the

reference characters

8 and 9, which are interchangeably adapted for selective frictional driving engagement with the metal pulley portion 7a of the final drive idler wheel 7.

The final drive wheel 7 is of duplex construction, having the aforesaid metal pulley portion 7a which is of relatively larger diameter, additionally supports an uppermost coaxial rubber pulley 7b which is of relatively reduced diameter. The pulley portion 7a thus functions as the power input pulley of the wheel, whereas the pulley 7b is the power take-off pulley thereof since its preferably rubber rim 7b is adapted to be engaged, as best shown in Figs. 1 and 5, with the internal tubular surface of a pendant tubular flange 1a of such a turntable as is shown at 1,

which is here shown as being of a recent commercial type whose diameter is usually about five inches.

The pulley 7b is peripherally fitted onto a tubular flange 7c which is rigidly secured by its base within a central aperture of the cup-shaped pulley 7a, said tubular flange also affording a hub for said duplex idler wheel element. A journal post 15a for the wheel extends upwardly from a universally laterally movable U-shaped supporting plate 15, a tubular bearing bushing 15 being telescoped over said post within said tubular flange 7c, and is maintained in place between the post shoulder 15c and a washer 15d by a screw 15:; threaded into the upper end of the post 15a.

The post 15a is rigidly secured by riveting its lower end to the web portion of the U-shaped member 15, the arms of said member extend in laterally interspaced parallel relation between

radial flanges

21 and 22 of a post 23, which flanges afford a supporting slideway for said arms and on which the member 15 may be rotatably swung, and at the same time may be longitudinally slid. A pin 15b carried by one of the arms of said member, by engagement with the lateral surfaces of the

post flanges

21 and 22, prevents undue longitudinal forward movement 0 the member 15.

A tensile spring 24 secured at its two ends, to a pin 24a carried by the frame 12, and at 2411 to the web of the U-shaped member, yieldably tends to so move the idler wheel 7 as to cause its pulley 7b to engage the inner cylindrical surface of the turntable flange 1a and to simultaneously effect pressure engagement by the wheel pulley 7a with that one of the

idler pulleys

18 or 19 which is in adjusted operative position as shown for the pulley 18 in Figs,- 1 and 3, and for the pulley 19 in Figs. 2 and 4.

The

idler pulley elements

8 and 9 are best shown in Fig. 11, each thereof having an uppermost single rubber pulley, each being respectively shown at 18 and 19, and both said pulleys are located at the level of the pulley flange 7a of the duplex idler wheel element 7 with which said

pulleys

18 and 19 are selectively interchangeably adapted to be peripherally engaged.

The idler pulley element 8 is provided with a second rubber pulley 18:: which is disposed at the lower level of the lowermost motor shaft step 6. Referring particularly to Fig, 11, the

idler pulley elements

8 and 9 are similarly provided with a tubular metal hub a, which is preferably closed at its upper end, and into which a metal bearing liner bushing b is tightly fitted. Posts 8c and on which the

respective pulley elements

8 and 9 are journalled, are secured to a swingable supporting plate 40, by their reduced lower rivet end extensions 1 each of which are first projected through diiferent of a pair of small laterally interspaced apertures of said pulley plate 40, said ends being then riveted over at the under side of said plate to fixedly secure said posts thereto. Each of said posts is intermediately circumferentially grooved to permit a C-spring wire 8d to be disposed within the groove, each said spring being adapted to yieldably frictionally restrain removal of each said

element

8 or 9 from its associated journal post.

Although two

rubber pulleys

13 and 18a for the element 8, are shown in relatively superposed interspaced relation on the hub a of the pulley element 8, a single rubber longer pulley may be substituted for said pair of pulleys, provided that such single pulley shall be of such longitudinal extent that its upper portion shall be disposed at the level of said idler wheel pulley 7a, and at the same time, its lower portion shall be at the level of the aforesaid lower motor shaft step 6, so that said portions may respectively be concurrently engaged with said pulley 7a and said shaft step pulley 6, such an elongated pulley being shown at 42, in Fig. 13, later referred to.

The swingable plate 40, which supports the idler pulley elements, is journalled to permit swinging adjustment movements about the axis of a machine screw 20, in response to swinging adjustment movement imparted to an underlyingswingable plate 4 whichi-s provided with a laterally extending handle 4a, which is movable to different adjustment positions in a path of movement of like directional nature throughout its extent.

Swinging adjustment movements of the plate handle 4a is communicated through the plate 4 to the adjustable pulley-supporting plate 40, by virtue of an upstanding stud projection 4b which at its lower end is rigidly secured to the handle plate 4 and projects upwardly through an aperture 40x of the pulley plate 40, the diameter of said aperture being substantially in excess of that of the projection 4b whereby a lost-motion interlockingrelation between said plate 4 and said plate 40 is effected. Similarly, the

plates

40 and 4 are secured together by the screw 20 over the lower end portion of which adjacent to its head is telescoped a metallic bushing having a lowermost radial flange and an upstanding tubular flange.

To swingingly adjust the idler pulley supporting plate 40, the underlying actuating plate 4 having the outwardly extending handle are secured to the common frame 12 by a screw 20 which is projected upwardly through the bore of a bushing 31, having a lowermost radial flange 31b and an upstanding tubular flange 310, the latter being successively projected through the elongated aperture 31a of the assembly plate 12, and a circular aperture of said actuating plate, the threaded end of said screw then being tightly secured within the small threaded aperture of the plate 40, and said screw being effective to clamp said .bushing against the underside of the plate 40, and said assembly of

plates

40 and 4 being together end-wise reciprocable, by lateral movements of the tubular flange 310 along the major axis of the elongated plate opening 31a, the end edges of said elongated opening limiting such movements.

- Limited relative rotation of the

plates

4 and 40 is permitted to the extent of play between the sides of a relatively interlocking upstanding pin 4b, secured to the plate 4, and the edges of an aperture 40x of larger diameter, into which said pin projects. Aligned

arcuate openings

29 and 29a of the

respective plates

40 and 4 and a circular opening of the main plate 12 permit the pulley end portion of the motor shaft to be freely projected vertically upwardly through said plates, even when the

plates

4 and 40 are swung to their extreme opposite adjusted positions.

A swingable lever 25, intermediately carrying an upstanding locking pin 25a, is journalled at one end on the pin 24a which is rigidly secured to the plate 12, and is biased by. a spring 25b which is secured by its two ends respectively to the opposite end 250 of the lever 25, and to the frame 12, at 25d, said spring being yieldably effective to snap the locking pin 25a into one or another of the

end edge notches

27 and 28 of the swingably selector plate 40 which carries the

idler pulley elements

8 and 9, to ensure that a selected pulley is located in its proper operative position. To place either selected of the pulley elements in the respective operative positions of Figs. 1 and 3 for the element Sand Figs. 2 and 4 for the element 9, wherein the pulley 18 or the pulley 19 of the selected element is in power transmitting frictional driving relation with the periphery of the idler wheel pulley 7a, and respectively concurrently the pulley 18a, or the pulley 19, is likewise frictionally engaged with the

shaft steps

6 or 5, respectively, the handle 4a is swung from one side as in Figs. 1 or 2, to the other side.

Such handle movements are about the axis of the screw 20 (Fig. 7 and are effective to move said pulley elements processionally arcuately. The elongated aperture 31a of the main plate 12 permits slight variations from true arcuity of plate movements which is desirable to ensure uniform pressure of engagement between the different-said idler pulleys and the relatively engaging shaft steps and the wheel pulley 7a.

The lever 25 transmits to the

plate

4 and 40 biasing spring pressure exerted, by the spring 25b, by virtueof the engagement between'the leverengaged edges of the plates and the pin 25a, carried by said lever, to ensure sufficient but not excessive pressure between respective of the shaft steps 5 or 6 with the operatively positioned one of the idler pulleys 19 or 1811 according to the swung adjustment position of the

idler pulley elements

9 or 8 respectively, and said spring 25b and lever 25 also are effective to yieldably so bias that one of the

idler pulley elements

8 or 9 which has been adjustably swung to its operative position, between the wheel pulley 7a and the shaft, in such a direction that the periphery of its

pulley portion

18a or 19, will be spring-pressed against its associated engageable shaft step.

To some extent the spring 24 by force resiliently supplied to the laterally movable support 15 for the wheel 7, supplements and adds to the pressure engagement, between said

pulley

19 or 18a and the thereby engaged shaft step, which is effected by the aforesaid spring 25b.

The cam surfaces of the edge 4c of the plate 4 are adapted to cam the pin 25a of the lever 25 outwardly of the

notches

27 and 28 against the pressure of the spring 25b, to permit the plate 4 to transmit swinging adjustment movement to the plate 40 and to permit its displacement by the pin 4b, from either adjusted position as respectively shown in Fig. 1 or 2, wherein it has been previously locked by said pin 2511 being projected into one of said notches, to the alternative adjustment position wherein said pin is caused to enter the other of said notches.

The above arrangement of plates, and ancillary locking pin, is substantially the same as disclosed in the previously identified Gay patent, to which reference may be had with respect thereto.

From the foregoing, the operationv of the first embodiment of my invention, as shown by Figs. 1 to 11 inclusive, will be readily understood, such operation being here briefly summarized. Assuming the mechanism comprising the final drive idler wheel 7, the idler pulleys 8 and 9, and the motor M, the latter with the uppermost portion of its shaft being formed to provide the superposed

shaft steps

5 and 6 being, with means ancillary thereto as described, unitarily carried by the plate 12, said mechanism is applied to the driving of such a turntable as that shown at 1, and for this purpose by screws and

grommets

13 and 13a, the plate is secured to the turntable platform 2 as shown, with the periphery of the rubber pulley portion 7b of the duplex final drive pulley wheel being maintained in spring-pressed engagement with the inner surface of the turntable flange 1a, by virtue of the spring 24. At such time the second pulley 7a of said wheel is, by pressure of the same spring 24, pressure-engaged with that one or the other of the idler pulleys 18 or 19 which is in adjusted operative position, which for either of the-

pulley elements

8 or 9, will hereafter be understood to be that position wherein the uppermost idler pulley of such element is engaged with said wheel pulley 7a.

To achieve selective operative positioning of one or the other of said pulley elements it is only necessary to swing the handle 4a of the lever 4 to the right or left, as may be necessary to place the

pulley elements

8 and 9 in that adjusted position wherein the desired

uppermost pulley

18 or 19 is engaged with said idler wheel pulley 7a, i. e. as shown in Figs. 1 and 3 for the uppermost idler pulley 18 or the element 8, and as shown in Figs. 2 and 4 for the idler pulley 19 of the element 9. The

steps

5 and 6 of the motor shaft have effective diameters which are relatively proportional to the turntable speeds which result when one or the other of said steps is frictionally engaged with its respectively relatively associated

idler pulley

19 or 18. Y

Thus, for desired turntable speeds of 33 and 45 R. P. M. to be achieved by frictional driving of the

respective pulley elements

9 and 8 by the respective drive

shaft pulley portions

5 and 6, the effective diameter of said shaft. step

pulley portions

5 and 6 should be in the ratio of 33:45, and all of the rubber idler pulleys shown at 19, 18 and .18a,are here assumed to be of relatively like diameters, but with variations being pernfiissihle,

The wheel 7 being 'frictionally driven by engagement of one or the other of the idler pulleys 19 r 18 with its lowermost wheel pulley 7a, and the uppermost wheel pulley 7b being frictionally engaged with the flange 1a of the turntable 1, the turntable will be driven at the the same peripheral speed as that of the periphery of said pulley 7b. The effective diameter of said pulley 7b, in the exemplary showing of the drawings, being about forty percent (40%) of the diameter of the pulley 7a, its peripheral speed will be correspondinly reduced, relative to that of the wheel pulley 7a, and the peripheral speed of the turntable 1, driven thereby, will be correspondingly reduced.

The handle 4a being integral with the plate 4, provides a lever handle therefor which when manually or otherwise swung laterally in opposite directions will interchangeably dispose either of the

pulley elements

8 and 9 in the operative positions shown for each, respectively in Figs. 1 and 3.

With the parts in the positions shown in Fig. l, the lowermost pulley portion 18a of the element 8 is operatively engaged with the pulley 7a of the duplex idler wheel 7.

In the above case the motor shaft being rotated, the shaft step 6 affords a driving pulley to drive the pulley 18a of the element 3 which is thereby rotated while frictionally driving the idler wheel pulley 7a, whereby the uppermost wheel pulley 7b which is engaged with the inner surface of the turntable flange drives said turntable at a rate of speed which depends on the rate of rotation of the motor shaft, and the ratio of diameters of the shaft step 6 to the pulley 18a; other factors such as the relative diameters of the duplex wheel pulley 7a and 7b, as elsewhere herein referred, may further modify the driving ratio between the shaft 16 and a turntable such as that shown at 1. l

The provision of rubber instead of smooth metal surfaces for the wheel pulley 7b, and for the idler pulleys 18 and 19, is for the purpose of making one of each pair of relatively engaging pulley surfaces of rubber, whereas the other thereof is of smooth metal, whereby greater friction is achieved between the driving and/or driven surfaces of each pair.

In either position of adjustment of the plate 40, to dispose either of the

idler pulley

19 or 18a in engagement with the respective upper or lower pulley steps or 6 of the shaft 16, the other of said

idler pulleys

18a or 19, is maintained out of contact with any pulley step of said shaft.

Also when the lower pulley 18a of the element 8 is in engagement with its operatively associated shaft pulley step 6, as shown in Fig. 3, since the diameter of the upper pulley 18 of said element 8 is not greater than, and as here shown, is equal to the diameter of the lower pulley 18a, and the shaft pulley step 6 being of greater l diameter than the upper step 5, the said upper pulley 18 cannot then be engaged with the upper shaft pulley step 5, but instead is solely engaged with the metal periphery of the pulley 7a of the duplex wheel pulley 7. Thus, the lower pulley 18a is driven from said lower shaft pulley step 6, thus rotating the common hub a for both upper and lower idler pulleys, and thus the tional driving engagement with, the motor shaft step result of engagement of the rubber-treaded wheel pulley 7b with the turntable flange 1a. Y

The pulley element 9 has but the single rubber pulley 19 whose different sides may be concurrently engaged respectively with the upper shaft pulley step 5, and with the said lower duplex wheel pulley 7a.

All of Figs. 12 to 15 inclusive are showings of mechanisms, generally of the nature of those of Figs. 1 to 11 hereof, but differing therefrom, in that they show such a mechanism which is adaptable to drive a turntable at any of three different speeds which, for instance, may be 33 R. P. M., R. P. M., and 78 R. P. M.

In Fig. 12 a showing is made of the use of a final drive wheel 79 affording a single pulley having a rubber rim directly engaged with a turntable flange 100 and also adapted for selective engagement with an

uppermost metal pulley

44, 45 or 46 of one or the other of the

idler pulley elements

57, 58 or 59, which are shown in side elevation in the intermediate showing of Fig. 15.

Fig. 12 is more particularly related to Fig. 15 which shows, partly in elevation and partly in vertical trans verse section, views of the several parts involved in the transmission of power from the motor to the turntable, a fragment only of which is shown at the correct relative elevation with respect to the parts of the

idler pulley elements

57, 58 and 59, and to the successive steps 50, and 88 of the motor shaft 109, an uppermost fragment of which is shown at the left in Fig. 15, said steps being respectively laterally aligned with the rubber pulleys 41b, 42b and 43b of the respective said elements.

Figs. 12 and 15 show a rubber rim r for the idler wheel 70, whereby it is adapted for eflicient frictional engagement with each of the metal idler pulleys 44,. 45 and 46, and also with the metal turntable flange 100. The effective diameter of said wheel 70, is so co-related with the diameters of each of the shaft steps 51), 60 and 80, and with the rate of rotation of the shaft 109, that the wheel 70 will drive the turntable at any desired one of the aforesaid desired respective rotational speeds, when the respective rubber pulleys 41b, 42b and 4312 are each, in turn, engaged with the shaft steps 50, 60 and 80, which, as shown in Fig. 15, are at the respective levels of the different of said rubber pulleys.

At the right side of Fig. 15 is shown the final drive wheel 70 whose rim 70r is shown in engagement with the flange of a phonograph turntable, said rim being also adapted to be engaged and driven by any of the

pulleys

44, 45 or 46 as may be operatively adjusted by the handle 104a, Fig. 12, to effect such engagement. The said pulleys, shown at the middle of Fig. 15, are carried by different rotatable hubs a which are separately journalled in laterally interspaced relation on the common swingably adjustable plate 140, said plate being adjustably swung by the underlying plate 104 having a handle 104a in the same manner as the plate 4 swings the plate 40 as previously described in the embodiment of Fig. 1 to 11 inclusive; the uppermost fragment of the motor shaft 109 is shown at the left side of each of Figs. 13, 14 and 15.

The use of a metal pulley at the upwardly extended end of the

pulley elements

44, 45 and 46 of Fig. 15 is to improve the frictional driving function, as compared to the use of a rubber pulley to drive such a wheel pulley as that at 70 which has a rubber rim 70r, since the apparatus of Fig. 15 is intended to drive a wheel pulley 70 of the type having such a rubber rim 70r, and which can, therefore, efliciently drive a metal flange 100 of a turntable.

The showings of Figs. 13 and 14 are of the same type as those of Fig. 15, except that the duplex idler wheel 7 of the first described embodiment, is shown therein, and resultantly only rubber pulleys are provided for the

idler pulley elements

41, 42 and 43 of Fig. 13, and for the

similar elements

41a, 42a and 43a of Fig. 14. H

Actually the showings of Fig. 13 and Fig. 14, are functionally identical, the only difference being that in Fig.

14, the upper and lower pulley portions 42" and 43" for the

idler pulley elements

42 and 43 respectively are relatively longitudinally interspaced, whereas in Fig. 13, both upper and lower pulley portions for each of the corresponding pulley elements 42a and 43a are each shown as being merely upper and lower portions of a single tubular rubber piece.

The single rubber pulley 41 of Fig. 13, and the single rubber pulley 41a of Fig. 14, correspond, functionally and in structure, with the pulley 19 of the element 9 of the first described embodiment hereof, being similarly selectively concurrently engageable with the uppermost shaft step 50, and with the rim of the pulley 7a of the duplex wheel 7 to effect driving of the wheel by said uppermost shaft step.

With respect to the lowermost pulley portions of the elongated rubber pulleys 42 and 43 of Fig. 13 which portions are respectively at the levels of the respective shaft steps 60 and 80; said portions are respectively adapted to be selectively engaged with the said respective steps whenever the associated uppermost pulley portion of the same pulley element is selectively engaged with the wheel pulley 7a; similarly, the lower rubber pulleys 42" and 43" are respectively selectively engageable with the respective shaft steps 60 and 80, whichever is at the same level, whenever the associated uppermost rubber pulley 42a or 4301 is selectively engaged with the wheel pulley 7a.

The operation of the embodiments of 12 and 15, and also those respectively outlined in Figs. 13 and 14 will be well understood from the foregoing, and including the disclosures which relate to Figs. 1 to 11.

The different embodiments of my invention previously described possess the advantages that the single stepped motor shaft or driving pulley thereof affords by said steps, a plurality of power take-off pulleys, whose relative diameters are different, whereby those of greater diameter will impart to a driven pulley a greater peripheral speed than will those of less diameter and such peripheral speed may be, thence imparted by such pulley to the final drive wheel, which may be of the simplex type shown in Fig. 12 or to one of the pulleys of the duplex wheel 7 of the first embodiment whereby reduced peripheral speeds may be imparted to the turntable by the second pulley of said wheel which is of less diameter.

The use of the duplex pulley is optional but possesses the advantage that where, as in Figs. 1 to 11, the turntable is of relatively small diameter, the pulley steps of the motor shaft may be made relatively larger than otherwise would be the case if a simplex type wheel were employed to drive such a turntable. However, for driving of turntables of the usual greater diameter, it is believed that the simplex wheel will usually be preferred.

In the said embodiments, the idler pulleys of the character of those shown at 18 and 18a are employed which are of like diameters which is a convenience in manufacture, and for most purposes, no advantage will be achieved by making relatively upper and lower pulleys of a set of different diameters to modify the driving ratio between the final drive wheel and the pulley portions of the motor shaft.

However, in the broader aspect of my invention such variations in diameters, between upper and lower pulleys of the same pulley element or as between pulleys of different pulley elements, may be employed to achieve a somewhat different driving ratio between the motor shaft and the turntable.

Having shown herein a two-speed selective drive mechanism in Figs. 1 to 11 inclusive and three-speed drive mechanisms in Fig. 12 to 15 inclusive, it will be understood that by adding additional pulley elements to increase their number and disposing these in laterally interspaced relation on a somewhat wider adjustable mounting plate such as that shown at 40, Figs. 10 and 11, or at 140, Fig. 12, and by adding additional stepped portions 10 to the shaft 16 or 109 a greater number of'turntable speeds may be selectively achieved.

It will be understood that the drawings are not necessarily made to scale, but the dimensions thereof will be readily understood by those skilled in the art in view of the descriptive specification hereof, and it will be further understood that with the diameters of the different motor steps being approximately in direct proportion to the rate of rotation of the turntable, the rate of roation of the motor shaft under load, is a factor in the correct determinaiton of the precise diameters of said steps, since it is obvious that a motor speed of 3000 R. P. M. will drive the turntable at a fifty percent (50%) greater rotation rate than would a motor of 2000 R. P. M. Hence, the shaft stepped diameters must, in each case, be co-related with the rotational rate of the motor shaft during actual use of the mechanisms.

Having thus described my invention in different embodiments, I am aware that other numerous and extensive departures to those herein set forth may be made, but without departing from the spirit of my invention.

I claim:

1. In a multi-speed frictional drive mechanism for phonograph turntables having a pendant annular flange, the eombinaiton with a frame unitarily supporting all parts of the mechanism which comprises a friction driving pulley wheel adapted for peripheral friction driving engagement with the flange of a turntable, a motor pendantly supported by the frame with an end portion of its drive shaft projected upwardly through an aperture of the frame, said shaft portion being of stepped formation so as to afford a plurality of friction pulley steps which are of successively reduced diameters proceeding upwardly to an uppermost pulley step which is of least diameter, a plurality of idler pulley elements, an adjustably movable turret member on which said idler pulley elements are journalled for rotation on relatively parallel and laterally interspaced axes, at least one of said pulley elements having a pair of pulley portions which are respectively disposed at different levels, and each element having one uppermost pulley portion which is disposed at the level of a pulley portion of said wheel, each of said uppermost pulley portions of the different elements being adapted to be interchangeably frictionally engaged with a pulley portion of said wheel in response to adjustment moveturret member to relatively different adments of said justrnent positions, and each said element having a pulley element which in the case of different elements is respectively located at the level of a relatively different one of said shaft pulley steps and is adapted to frictionally concurrently engage that shaft step which is at the level thereof whenever the said uppermost pulley portion of the same element is engaged with said wheel pulley portion.

2. The mechanism substantially as set forth in claim 1, wherein the stepped end portion of the shaft is of substantially non-compressible material, and all' said pulley portions of said idler pulley elements being of rubber or functionally equivalent relatively compressible material.

3. The mechanism substantially as set forth in claim 1, wherein all said pulley portions of said idler pulleys are of corresponding diameters.

4. The mechanism substantially as set forth in claim 1, wherein a relatively lower pulley portion of each pair afforded by any said idler pulley element being engageable with a step of said shaft which is of greater diameter than a relatively upper shaft pulley step which is at the level of the relatively upper of said pair of idler pulley portions, and said upper and lower idler pulley portions being respectively of such diameters that during such engagement of a lower shaft pulley step by said lower idler pulley portion, the opposing outer surfaces of said upper shaft step and said upper idler pulley portion are relatively laterally interspaced as a result of said engagement.

5. The mechanism substantially as set forth in claim 1,

characterized by said idler wheel having a pair of relatively superposed co-axial pulley portions, the periphery of one of which is of compressible material which is engageable with a lateral surface of a turntable flange to drive the turntable, and the periphery of the other of said co-axial pulley portions being selectively engageable with one or another of said uppermost pulley portions of the respective idler pulley elements.

6. In a multi-speed frictional drive mechanism for phonograph turntables having a pendant annular flange, the combination with a frame unitarily supporting all parts of the mechanism, said parts comprising a friction driving pulley wheel having a rubber faced peripheral portion which is adapted for peripheral friction driving engagement with the flange of a turntable, a motor pendantly supported by the frame with an upstanding end portion of its shaft being of stepped formation so as to afford a plurality of friction pulley steps which are of relatively different diameters, a plurality of idler pulley elements, each affording at least a single pulley, a support member on which said elements are journalled for rotation on relatively parallel and laterally interspaced vertical axes, said support member being so carried by said frame, and being so adjustably movable in lateral directions as to processionally and concurrently move all said elements in a path of movement which is substantially of like directional nature throughout, to selectively interchangeably dispose any of them in a common operative position, wherein one pulley portion of any of different of said elements, is disposed at the level of a relatively different one of said shaft steps and is adapted for engagement with that shaft step which is at its same level, at least one of said pulley elements having a plurality of pulley portions disposed at different levels and each element having one uppermost pulley portion which is disposed at the level of a .pulley portion of said wheel, each of said uppermost pulleyportions of the different elements being adapted to be interchangeably frictionally engaged with a pulley portion of said wheel in response to such adjustment movement of said support member which is required to dispose that pulley portion of the element in relatively different adjustment positions and each said different element having a pulley element which in the case of the said different elements is respectively located at the level of a respectively different one of said shaft steps, and which is adapted to frictionally concurrently engage that shaft step which is at the level thereof whenever the said uppermost pulley portion of the same element is engaged with said wheel pulley portion.

7. A plural-speed friction drive mechanism for selectively driving a phonograph turntable of the type having an annular flange, at different speeds, comprising a vertical motor shaft of stepped formation to afford a plurality of pulley steps of relatively different diameters, a final drive wheel having a friction tread which is adapted to be peripherally engaged with the flange of a turntable, a laterally movable mount affording a journal upon which said wheel is rotatable about a vertical axis, a laterally adjustable pulley carrier, a plurality of idler pulley elements journalled in laterally interspaced relation for rotation on said carrier each being rotatable on a vertical axis, at least one of said idler elements having a pair of relatively upper and lower pulley portions and all thereof having a rela tivelyupper pulley portion, the diameters of all said pulley portions being substantially the same, said upper and lower idler pulley portions of said pair being respectively disposed at the level of said wheel tread and at the level of an associated one of said shaft steps, spring means biasing said wheel mount to yieldably press said Wheel tread toward said motor shaft, and said carrier being adjustably laterally movable to different of successively dis- .pos'ed stations in a path of movement, which is of like directional nature throughout, to effect disposition of any of saidelements at the common operative position for all thereof, wherein the said upper pulley portion of each said operatively positioned element is in lateral frictional engagement with said wheel tread and wherein a pulley portion of any operatively positioned of said elements is concurrently in lateral frictional engagement with an associated shaft step which is at the level thereof.

8. The plural-speed friction drive mechanism substantially as set forth in claim 7, characterized by said carrier being rotatable about an axial portion thereof and said elements being disposed thereon in substantial concentricity with respect to said axial portion and processional movements of said elements being in a path which passes between said motor shaft and said final drive wheel.

9. The plural-speed friction drive mechanism substantially as set forth in claim 7, characterized by the uppermost of said shaft pulley steps being at the level of the uppermost of said pulley portions of all said elements, and one of said elements having a single pulley portion at said level and being adapted, in response to positioning of the element in said common operative position, to be interposed between and make concurrent frictional engagement with both said uppermost pulley step and said wheel pulley portion.

10. In a multi-speed frictional drive mechanism for phonograph turntables of that type which has a pendant annular flange, the combination with a frame unitarily supporting all parts of the mechanism, said parts comprising a final drive pulley wheel adapted for peripheral friction driving engagement with a turntable flange, a motor pendantly supported by the frame with an upstanding end portion of its shaft being of stepped formation so as to afford a plurality of successive friction pulley steps which are of relatively different diameters, a laterally adjustable support, a plurality of upstanding pulley elements journalled on said support for rotation on relatively laterally interspaced axes, an uppermost friction idler pulley for each of said elements, each said pulley being disposed at a common level which corresponds to a pulley portion of said wheel, at least some of said elements having, a second pulley portion disposed at a relatively lower level and a pulley portion of each said element being disposed at the level of a different, thereby associated, pulley step of said shaft, and adjustment means, adapted for movement to any of a plurality of stations which are located in a continuous path of like directional nature throughout, to effect disposition of any thereby selected one of said elements at a common operative position for each thereof, whereat a pulley portion of the selected ele ment is frictionally engaged with a shaft step which is located at the same level, and said wheel pulley portion is concurrently frictionally engaged with said uppermost pulley portion of said selected element.

11. In a frictional drive mechanism for a turntable of the type which is characterized by the turntable having an annular flange adapted for lateral frictional engagement by a friction wheel of the mechanism, comprising in combination, a motor and an upwardly extending shaft driven by said motor, said shaft formed with a plurality of drive areas of different diameters, a friction final drive wheel, a plurality of idler pulleys each having a pair of coaxial relatively superposed driving and driven pulley portions, said driving portions of the said idler pulleys being located in the plane of the final drive wheel, said driven portions of said idler pulleys being each located in the plane of an associated driving area on said shaft,

r means for positioning the axis of rotation of each idler pulley in an operating position comprising a plane defined by the axis of rotation of the final drive wheel and that of said shaft so that the driven portion of the idler pulley is in operational contact with the associated portion of said shaft and the driving area of the selected idler pulley is in operational contact with said friction final drive wheel.

12. In a frictional drive mechanism for a turntable of the type which is characterized by the turntable having an annular flange adapted for lateral frictional engagement 1 3 by a friction wheel of the mechanism, comprising in combination, a motor and an upwardly extending shaft driven by said motor, said shaft formed with a plurality of drive areas of different diameters, a friction final drive wheel, a plurality of idler pulleys each having a pair of coaxial relatively superposed upper driving and lower driven pulley portions, said driving portions of the said idler pulleys being located in the plane of the final drive wheel, said driven portion of said idler pulleys being each located in the plane of an associated driving area on said shaft, means for positioning the axis of rotation of each idler pulley in an operating position comprising a plane defined by the axis of rotation of the final drive wheel and that of said shaft so that the driven portion of the idler pulley is in operational contact with the associated driving area of said shaft and the driving portion of the selected idler pulley is in operational contact with said friction final drive wheel.

13. In a frictional drive mechanism for a turntable of the type which is characterized by the turntable having an annular flange adapted for lateral frictional engagement by a friction wheel of the mechanism, comprising in combination, a motor and an upwardly extending shaft driven by said motor, said shaft affording an upwardly located drive pulley having a plurality of drive areas of different diameters, a friction final drive wheel, a laterally movable mount affording a journal adapting said wheel for rotation upon a vertical axis, a plurality of idler pulleys each having a pair of coaxial relatively superposed driving and driven pulley portions, said driving portions of the said idler pulleys being located in the plane of the final drive wheel, said driven portions of said idler pulleys being each located in the plane of an associated driving area on said shaft, means for positioning the axis of rotation of each idler pulley in an operating position comprising a plane defined by the axis of rotation of the final drive wheel and that of said shaft drive pulley so that the driven portion of the idler pulley is in operational contact with the associated portion of said shaft drive pulley and the driving portion of the selected idler pulley is in operational contact with said friction final drive wheel.

14. In a frictional drive mechanism for a turntable of the type which is characterized by the turntable having an annular flange adapted for lateral frictional engagement by a friction wheel of the mechanism, comprising in combination, a motor and an upwardly extending shaft driven by said motor, said shaft affording an upwardly located drive pulley having a plurality of drive areas of different diameters, a friction final drive wheel, a laterally movable mount affording a journal adapting said wheel for rotation upon a vertical axis, a plurality of idler pulleys each having a pair of coaxial relatively superposed upper driving and lower driven pulley portions, said driving portion of the said idler pulleys being located in the plane of the final drive wheel, said driven portions of the said idler pulleys being each located in the plane of an associated driving area on said shaft, a common carrier affording separate laterally interposed journals for each said idler pulley, said idler pulleys being thereby adapted for rotation upon relatively parallel interspaced vertical axes on said carrier, which is adjustably movable to processionally move said pulleys to successively different positions which are interspaced at intervals in a single path of pulley movements, said path being of like directional nature throughout, and one such position of said path being a common operating position for said pulleys, wherein the respective upper and lower portions of an operatively positioned pulley are respectively disposed in peripheral engagement with said friction final drive wheel and the associated one of said drive areas of said drive shaft, said path of processional pulley movements extending longitudinally between opposite terminal portions disposed in interspaced relation to a vertical plane which includes the axis of said wheel and of said drive pulley, and the intermediate portion of said path being in intersecting relation to that portion of said plane which is interposed between said wheel and drive pulley axes, and said operative pulley position being located substantially closely to said intersection of said path and said plane.

15. A frictional drive mechanism as defined in the immediately preceding claim including resilient means cooperating with said laterally movable mount and carrier to assist in maintaining a drive transmission path after it has been established from an operatively positioned pulley to the turntable flange, by way of said friction final drive wheel.

References Cited in the file of this patent UNITED STATES PATENTS 2,518,769 Gay Aug. 15, 1950 2,583,972 Simonson Jan. 29, 1952 2,598,138 Sharp May 24, 1952