US1831238A

US1831238A - Multiple hydraulic drive

Info

Publication number: US1831238A
Application number: US257935A
Authority: US
Inventors: John P Ferris
Original assignee: Oilgear Co
Current assignee: Oilgear Co
Priority date: 1928-02-29
Filing date: 1928-02-29
Publication date: 1931-11-10
Anticipated expiration: 1948-11-10

Description

Nov. 10, 1931. JJP. FERRIS 3 iwL'rIPLE mnmumc- DRIVE Filed Feb. 29-. 1928 3 Sheets-Sheet 1 9 R. L/bHNEFEHZS...

ATTORNEX;

Nov. 10, 1931. v J. P. FERRIS ,8 MULTIPLE mR uLId DRIVE Filed-Feb. 29. .1928 3 Sheets-Sheet 2 INVENTOR. LZb HNEEEHJS A TTORNE Y.

40 Another object is the provision of improved Patented Novt 10, 1931 JOHN P. FEBBIS, F MILWAUKEE, WISCONSIN,

Assrenoa r0 THE OILGEAR COMPANY,

OF MILWAUKEE, WISCONSIN, A CORPORATION OF WISCONSIN murmur: mmnuc DRIVE Application filed February 29, 1928. Serial No. 257,935.

, This invention relates to multlple hydraulic drive systems for effecting the simultaneous operation of a plurality of independent elements at accurately controlledspeeds.

For purposes of explanation the invention will be described as embodied in a special type of crank shaft lath, wherein it is utilized as a an accurate feed mechanism for a plurality of independent tools, although it is capable of application to other types of machine tools and to other widely varying, arts, such for instances asa multiple pumping system for oil wells. 3

One object of the present invention is the provision of a hydraulic system through which a pluralityof independent elements may be simultaneously driven at accurately regulated rates from a single power source. Another object is the provision in a mule 2 'tiple drive system. of the character mentioned of means for effecting an accurate control of the rate and extent of movement of the several driven elements.

Another object is the provision in'a multiple drive system of the character mentioned of means for compensating for leakage losses to thereby maintain proper phaserelation between the several driving means. A'notherdabject is the provision in a mul tiple drive system of the character mentioned' of means for temporarily concentrating the entire'force of the power source upon any of the several-driving means; t

Another object is the provision in a-multinle drive system of the character mentioned of means for maintaining a different phase relation between the several driving means so that one "or more may complete the work-1 ing stroke ahead of others.

flexible connections for transmitting driving liquid to each hydraulic driving means. Other objects and advantages will appear from the-following description of an' illustrative embodiment of the present invention.

In the drawing's': I Figure 1 is a fragmentary plan view of crank shaft lathe equipped with a multiple hydraulicfeed system embodying the present 5 invention.

(Fig.2); bya gear 16. and at the other end by "axes of the two pins 14 and 17 of each frame Fig. 2 is a transverse section taken substan: tially along the line 2-2 of Figure 1.

' Figs. 3 and 4 are longitudinal sectional views of two flexibly connected fluid conducting links, which together form a flexible connection for conveying driving liquid to and from each feed cylinder. These sections are taken substantially along the lines 3-3 and 4- 4, respectively, of Figure 2.

Fig. 5 is a diagrammatic view of the hydraulic system. 7

The lathe shown in Figures 1 and 2 is designed to finish in one operation the cheeks a of the several'cranks b of a crank shaft 0 and also theseveral crank pins thereof. The crank shaft is shown mounted at one end upon a (lead center 10 and at the other end in a rotary chuck 11 of a well-known type driven clockwise (Fig. 2) by an appropriate gear 12. The crank shaft is thus rotated about its true axis causing the several pins ll thereof to follow circular orbital paths concentric with the axis. A plurality of tool supporting frames 13 are mounted to translate within circular orbital paths coextensive with the paths of the several crank pins (1, respectively, and in phase therewith. In this instance each "frame is supported at one end upon an ec centric pin 14 on a shaft'15, driven clockwise an eccentric pin-17, on a shaft 18 driven in' the same direction by a gear 19. The three gears 12, 16 and 19 are driven at the same rate through a gear 20 meshing therewith. The 1 are oifset equal distances and in the same direction from the axes of their respective shafts 15 and18, the extent and direction of oilset in each instance being equal to the ex- I tent and direction of oflfset of the corresponding pin (1 of the crank shaft 0, so that each frame moves parallel to itself and in the same phase as the corresponding crank pind.

, Each frame carries atool feeding cylinder 21. 22, 23, or 24 which mov'es'in unison therewith and encloses a

piston

25, 26, 27, or 28 closely.v fitted for lengthwise reciprocation therein. Each frame is also transversely bored to'receive and guide

arod

29, 30, 31 or 32 connected with the associated piston and

carryingalathe tool

33, 34, 35, or 36, adapted to operate upon one of the several pairs of cheeks a and crank pins (1. Each tool is given two distinct motions :-(1) a circular trans- 5 latory motion, imparted from the translatory motion of its supporting frame, by which it is caused to follow a crank pin (1 in its circular travel about the axis of the crank shaft, and (2) a rectilinear motiqn toward and from the axis of the crank pinimparted by the movement of its associated piston lengthwise of the

cylinders

21, 22, 23 or 24. I The

several pistons

25, 26, 27 and 28 are actuated and controlled by a multiple hydraulic drive system such as will now be described. In this system (shown diagrammatically in Figure 5) the rear ends of the

several feed cylinders

21, 22, 23, and 24 are hydraulically connected to the forward ends of

several impeller cylinders

37, 38, 39 and 40, respectively, through appropriate leads 41, to be hereinafter described; and the forward ends of the several feed cylinders are hydraulically connected to the rear ends of the several impeller cylinders, respectively, through similar leads 42. The several impeller cylinders contain coacting pistons 43, 44, 45nd 46, respectively, which are simultaneously driven by anappropriate crosshead 47 to which they are rigidly connected through appropriate rods 48. The arrangement is such that during each advance stroke of the cross head 47 each of the

several pistons

43, 44, 45, and 46 will advance and force liquid at a definiterate through the leads 41 into the several feed cylinders to thereby advance each of the

several pistons

25, 26, 27, and 28 at a definite rate, the liquid discharged from the forward end of'each feed cylinder returning to the rear endof each impeller cylinder through the respective leads 42;, and upon each return stroke of the crossheadthe

several pistons

25, 26, 27 and 28 are retracted by liquid delivered through the re- 45 spectiveleads 42 from the rear ends of the "impeller cylinders. The

several tools

33, 34.

35 and 36 are thus individually fed at definite I through a link 75 with an arm 76 projecting from the lever 51, so that the lever is caused t es toward and from the respective crank pmsd in accordance with the direction and rate of movement of the cross-head 47.

The cross-heads 47 is hydraulicallyt driven' in both directions and at controlled speedsby liquid supplied from a reversible flow, variable displacement pump 49 of a well known type. The pump shown is fully described in my copending application Serial No. 199,925, filed June 20, 1927, and it will sufiice here to state that it is driven at constantspeed from an appropriate source through a shaft 50, the direction and rate of liquid dischar ed thereby beingcontrolled bya lever 51. ith the control lever 51in the intermediate position shown pump dischar zero; When shifted toward the right hquid I 05 is discharged through outlet 52 at a ratedependent upon the extent of movement of the ever, an liquid returns to the pump through outlet 53; and when the lever is shifted toward the left liquidis discharged through outlet 53 at a rate dependent upon the extent of movement of the lever, and liquid then returns to the pump through outlet 52. In all positions of the control lever the by cause the cross-head 47 to execute a prede- To this end the termined operating cycle. pump control lever 51 is placed under the control of an appropriate cam, mounted for movement with the cross-head. Cam shown includes a plate 61 fixed to the cross-head and having an upstanding portion '62 of irregular form shaped to provide a straight edge 63, and a broken inclined edge .64, interrupted b a short straight portion 65. A cam bloc 66, adjustably fixed to the plate 61 and spaced from the upstanding portion 62."

In this instance the two main ciris also of irregular form. One side thereof i is shaped to match the portion 62 and the 7 other side is shaped to provide three straight gortions 67, 68 and 69 disposed at different istanees from the longitudinal center of the block. A pin 70, carried by one. arm of a bell-crank 71, is arran ed to 'coact with the

faces

63, 64 and 65 o the'portion 62 and the faces 67, 68,'and 69 of the block to determine the position dfthe bell-crank during movement of the cross-head. The bell-crank is fulcrumed, as at 72, upon an appropriate fixed bracket 73, and is yieldably urged to swing clockwise by the action of a spring 74. The other end of the bell-crank is connected to g upon its fulcrum 77 in accordance with the action of the bell-crank.

With the parts in the position shown the pin 7 0 is held by the spring 7 4-in intermediate neutral position against the inclined por-" tion 64 of portion 62, so that the lever" 51 is also in neutral position, there is noflop in leads 57 and 58 and the crm-headiiflis at rest. To start. the feed motion thejjl'ever 51 1S manually swung toward the right to thereby shift the bell-crank and pin 70 toward the left and cause the pump to deliver liquid at a high rate through-the lead 57 to the rear.

end of the motor cylinder 59, to thereby advance the piston 60 and-.cross-head 47. The hand lever 51 is'then released and the pin 7 0' tool. For this purpose a pair of independent- 1,ss1,2ss' I 3 first rides upon theiface 67 of the advancin an appropriate manner to the frame of the ing cam block 66 to thereby maintain the admachine, the leads being completed by pairs Vance of the cross-head at a relatively rapid of flexibly connected .fluid conducting links rate. This advance continues until the

85 and 86 through which the several passages 70 leaves the face 67 and swings toward the 41 and 42 communicate respectively with right into contact with face 68, thereby the opposite ends of the several moving feed swinging the lever 51

apredetermined discylinders

21, 22', 23 and '24. ta-nce toward neutral position and causing a Two links of a coacting pair are shown reduction in pump displacement. The crossin section in Figures 3 and 4. Each link conhead then continues to advance at a,slower tains two

longitudinal passages

87 and 88 75 rate until the pin 70 leaves face 68 and'makes or .87 and 88.- A pintle 89 fixed in and cont-act with face 69 to effect a similar adprojecting laterally from one end of link 85 justment of lever 51 and a further reduction is closely fitted to rotate within the adjacent in pump displacement. The cross-head then end of link 86 and provides a swivel conneccontinues to advance at a ill Slow r ra e tion therebetween; Pintle 89 is removably so until the pin 70 leaves face 69 and swings retained in'link 86 by appropriate means such intocontact with 'face 63 of portion 62. as a screw 90 and washer 91. The other end This action causes the lever 51 to swing of link 85 is mounted to swing upon a simithrough neutral position into an extreme polar pintle 92 fixed in and projecting from a sition, toward the left, so as to reverse the bracket 93 projecting from the rail 84. Pintle e5 pump and cause the same to deliver liquid at 92 is provided with two longitudinal pasa high rate through lead 58' into the

forward sages

94 and 95 which communicate through end of the motor cylinder 59, whereupon the

ports

96 and 97 and pipes 41 and42" with cross-head begins areturn movement at relthe transverse passages in the rail 84, and

a ively high Speed. This movem t nwhich also communicate through ports 98 90 tinues until the rate is reduced by the action nd 99 with the

passages

87 and 88 in the of inclined face 64 upon the pin 70. The link 85. Similarly

passages

87 and 88 in straight portion permits the cross-head to link communicate respectively with pastravel for a short distance at low speed after

sages

87 and 88 in link 86 through longi- 30 which the pin 7 0 is ultimately returned to the t dinal passages =2 00 and 101 in the pintle 89.

original neutral posit-ion by the continued A thi d' i fl 102 fi d i th d f li k 86 action of c 64 and e cross-head g i is closely fitted for rotation within the end j comes to rest. As hereinabove pointed out h d103 of on of the feed cylinders. A the variable speed advance and return movel ngitudinal passage 104-in pintle 102'con- 35 ments of the cross-head are transmitted to nects passage 87' i li k 86 with a. a ag on the

several pistons

25, 26, 7, and 28 ro g 105 leading to the rear end of the feed cylinthe several lmpeller cylinders 87, 38, 39 and d and a longitudinal passage 106 connects 40 to efiect the'advance and return of the passage 88 ith a i 107 l di t the several tools toward and from their respecf d d f th f d li d Th b tiW fi l P I draulic leads for both ends of each feed cylin-. 105

Provision s also made for individually d are th id d by a in l pair of. illmltlng the extent of advance a return f links-connectedin such manner as to permit ea h pls on 2 2 27 nd 28 t0 the e y PI free movement of the cylinder with its supgvide an extremely accurate control for each orting frame13. i

Each

lead

41 and 42 is connected with a 1y ad ustable hmitmg stops are provlded fo high pressure relief valve 108 of awell known each tool. Inthe form shown these stops comty e, I this in tance each of the several prise a pair of set-

screws

78 and 79 mounte relief valves is mounted upon the rail 84 in in suitable lugs 80 and 81 projecting from communication with one of the passages 41' .50 h t l carrying frame 13- Eaeh pair of or 42 in the rail, the liquid passing each valve. 1

screws coacts with an intermediate stop 82 being permitted to escape through a pipe 109 projecting-from h of h r dS 29,3 31 into a longitudinalpassage 110 in the rail. and.32 through a slot 83 in each frame-.' The ,Passage 110 communicates through an approengagementof stop 82 against, screw 78 limits priate lead 111 and connection 55 with the 55 the advance of the associated tool and the liquid reservoir in the base of the pump. A 1 engagement of stop 82 with screw 79 limits second longitudinal passage 112 in the rail is p the ret rn St k of the maintained flooded with liquid under low In the machine shown each of the several pressure supplied from the pump through ihydraulic leads 41 and 42, indicated diagramthe connection 54 and lead 113. A check valvemati'cally in Figure 5, consists in part of sepa- 114 between the passage 112 and-each ofthe rate pipe connections through which the opseveral passages 41' and 42' pe'rmitsthe ad positeends of the fixed impeller cylinders mission of liquid; thereto from passage 112 37 38, 39, and 40 communicate respectively whenever the pressure in any of the several with separate passages'41' and 42 leading main leads'41, and 42 falls below that in the n transversely througha fixed rail 84 attached passage 112. These leads are thus always 133:-

maintained flooded with liquid under pressure. A third longitudinal passage 115 in the rail is permanently connected through a lead 116 with the power lead 57 leading to the rear end of the motor cylinder 59. A check valve 117 between the passage 115 and each of the passages 41 permits liquid to escape from any of the leads 41 wheneverthe pressure therein exceeds the pressure in the passage 115.

The stroke of the cross-head 47 is such that it continues to advance for a brief time interval after all of the

tool feeding pistons

25, 26,27 and 28 have been arrested by the engagement of their respective stops 82 against the coacting screws 78, and such that it continues its return movement for a brief time interval after all of the feed pistons have been arrested by the engagement of their respective stops 82 against the coacting screws 79.

During the continued advance of the sev-'

eral impeller pistons

43, 44, 45 and 46, after the advance of the corresponding feed pistons has been arrested, the excess liquid in the several leads 41 escapes through the corresponding high pressure relief valves 108. and liquid under low pressure is admitted to the several leads 42 through the correspond ing check valves 114 to thereby maintain these leads and therear ends of the

impeller cylinders

37, 38, 39 and 40 flooded. The several ,feed pistons are thus in readiness to start simultaneously on a return movement immediately upon the reversal of movement of the cross-head. In a similar manner excess liquid is permitted to escape from the several leads 42 through their respective high pressure relief valves 108, and liquid is 'admitted to the several leads 41 through their respective check valves 114 to keep the same flooded, during the continued return movement of the several impeller pistons after the return movement of the several feed pistons has been arrested by the stop screws 79; and the several feed pistons are thus in readiness to advance simultaneously immediately upon the next advance of the cross-head. A hydraulic compensating system is thus provided with functions to maintain adefinite operating phase relation between the several feed pistons in spite of any leakage lossesin the system.

It will be noted that during both the advance and return strokes of the impeller and feed pistons the several cylinders of each group receive their supply of liquid primarily from the discharge of liquid from the several cylinders of the other group. To

make the rate of discharge from each cylinder of one group exactly equal to the intake demand required by a connected cylinder of the other group is a practical impossibility due to unavoidable leakage and mechanical inaccuracies. This leads to serious difiiculties. For instance, if during the return stroke of piston 25 the rate of discharge from the rear end of cylinder 21 be only slightly greater than the rate of suppl demanded by the cylinder 37, an excessive ack pressureis set up in the lead 41 causing the piston 25 to stioned that during the advance stroke the 0 rate of discharge fromthe forward end of each feed cylinder is slightly less than the supply demand of the rear end of the associated impeller cylinder, liquid being admitted to each of the leads 42 throughthe check valves 114 tomake up for this deficiency and thereby keep the impeller cylinders full. During this advance the several check valves T17, hereinabove mentioned, are kept closed by the pressure in passage 115 transmitted from the working pressure in the lead 57 by which the piston 60 is advanced. With the cylinders and rods thus proportioned the rate of discharge from the rear end of each feed cylinder, during, the return stroke, is slightly as i in excess of the supply demand of the forward end of the associated impeller cylin-- der. During the return stroke however the pressure in the lead 57 is of course reduced,

since this leadis then only carrying the dis- 10o charge from cylinder 59, and. the several check valves 117 function to permitthe escape of excess liquid from the several leads 41 and thus prevent the building up of excessive pressures therein. The check valves 117 tolo:

gether with check valves 114 thus effectively compensate for inequalities between rates of discharge and supply demands of the connected cylinders.

vA brief description of the operation of the 1 machine will now be given. Let it be assumed that the crank shaft 0 has been applied, as indicated, and that the three

gears

12, 16, and 19, are rotating clockwise (Fig. 2) under the action of the driving gear 20, so that the '11:

crank shaft is rotating clockwise, the several crank pins (1 are following a circular path, and the several tool carrying frames 13'are translating with a circular motion similar to and in exact phase with the'respective crank pins. Let it also be assumed that the

several feeding pistons

25, 26, 27, and 28 are retracted so that the

several tools

33, 34, 35 and 36 'are withdrawn from the work, and

that the cross-head 1,47, block 66, pin 70,

and controllever 51 are in the respective positions indicated in Figure 5. To start an operating cycle the operator shifts the hand lever "51 into right extreme position, whereupon the pump delivers liquid'at a high rate o by cylinder 37, an excessive back 75 through the lead 57 and the cross-head 47 and" impelling

pistons

43, 44, 45 and 46 advance rapidl The operator then releases the lever 51 an permits the in 70 to ride upon the face 67 of the cam lock and the rapid ad vance continues. During this advance the

several feed pistons

25, 26, 27 and 28 are advanced at a corres onding rate causing the several tools to a yance toward the work.

Just before the tools are actually engaged between the several airs of cheeks a on the crank shaft the pin 0 leaves face 67 and contacts with face 68 of the cam block to thereby reduce the rate of advance of the cross-head 47 in the manner hereinabove described, whereupon the rate of advance of the several tools is correspondingly reduced to a I rate appropriate for a light cutting feed.

This rate of advance continuesuntil just prior to actual engagement of the cutters with the several crank pins, at which time the pin leaves the face 68 and contacts with face 69 to thereby further reduce the rate of advance to that appropriate for a heavier cut ting feed. This slow advance of the tools continues until each is arrested by contact of-its associated stop 82 against the cooperating screw 78. Thereafter the slow ad- Vance of the cross-head 47 continues until .stroke as hereinabove describe the pin-7O leaves the face 69. of cam block 66and shifts into contact with face 63 of portion 62, whereupon .the pump reverses and the cross-heau begins 'a ra id return As the cross-head reverses .its motion the several 7

feed pistons

25, 26, 27 and 28 are simultane ously actuated and begin a'rapid return movement withdrawing the several tools from the pin-70' wit the face 64 of about the time the pin reac work. This movement of the tools continues until the s eed is reduced by contact ofthe lportion 62, and

es the. straight portion of portion 62 the several stops 82 engage the screws 79 and the several'feed pistons and'tools come to rest. .Thereafter the cross-head 47 continues its return move.-

ment, but at a gradually reduced rate until Y .the pin is returned to neutral osition by the action of face 64 and the crosso r if-5 a It will be noted that the ciit becomes considerably heavier as the was, near the end of their forward feeding stroke,engage their respective crankpins, and in order to avoid ead comes an excessive peak load on the machine from this cause, provision is'preferably made by 1 which the several tools may be advanced into contact with their respective crank pins successively rather than simultanenously. This is accomplished by so adjustinfg the several screws 79 as to stop the several eed cylinders and tools at diflerent points in their return strokes. For example, asindicated in Figure 5, the feed piston 25 has been permitted to .returna greater distance than the feed pis ton 26, by reason of a variation the settin of t eir respective stop screws 79, and tool 34 (connected with p1ston,26) is correspondingly advanced with respectto tool 33 (connected with piston 25). Both

tools

33 and 34 move forwardly simultaneously and at the same rate during the next advance stroke of the cross-head 47, with the result that tool 34, in advance of tool 33, actually engages its crank pin and completesthe cut thereon pin.

Provision is also preferably made for concentrating the entire force of the power source upon any oneof the several tools to thereby render available a pulling force of sufficient magnitude to extract a tool from the work in the event of a jam. To this end pro-, vislon is made for rendering any of the several high pressure relief valves 108 ineffective and for adjusting and retaining any of the check. valves 114 in open position. In this instance a valve in the form of a stem 118, is

screwed into the rail 84 beneath each relief valve 108, and is provided with a tapered end 119 adapted to enter and close 120 of the relief valve, to thereby render the same ineffective; and a stem 121 is screwedbefore tool 33 reaches its crank the inlet port impeller cylinders, are opened by adjustment i v of their respective stems 121 in the manner just described so these three leads are all open to the low pressure passage 112. With the valves thus adjusted the cross-head 47- is made to executea return stroke, and since the three impeller pistons 44, 45, and '46 offer no appreciable resistance to this movement of the cross-head practically the entire force of the motor cylinder 59 is concentrated upon the impeller through the lead 42to cylinder 21 at high pressure. Since the relief valve 108 connected with this lead has been renderedineffective,

thepressure therein is limited only by the force transmitted fromthe motor cylinder through piston 43; isordinarily sufficient'to extract the to i Various changes may-i be made inithe empiston 43, to thereby force liquid bodiment of the invention hereinabove specifically described without departingfrom or sacrificing the invention as defined in the ap pended claims. 1 .Iclaim:-'. I v 1. In a multiple hydraulic drive system the combination of a pl rality of liquid impelling means, means for aneously driv ng the same at regulated rates, a (plurality of sepaliquid imp ously rec procating the same at regulated rates, a plurality of separate hydraulically actuated reciprocating means, separate hydraulic connectionsbetween said plurality of impelling means and said plurality of actuated means through which said actuated means are individually reciprocated at regulated rates, and hydraulic compensating means automatically'operable to maintain a definite operating phase relation between said and an adfusta plurality of actuated means.

3. In a multiple hydraulic drive system the combination of a plurality of impeller cylin-. ders and coacting pistons, means for effecting relative reciprocation between said pistons and cylinders simultaneously and at regulated rates, a second pluralit of cylinders and coacting pistons, indivi ual hydraulic connections between said first and second named cylinders, respectively, for efi'ectin relative reciprocation between said secon plurality of cylinders and coacting pistons at regulated rates, and hydraulic compensating means automaticall operable to maintain a definite operating p ase relation between said second pluralityof cylinders and mad:- ing pistons.

4.. In a mi lgifple hydraulic drive system the combination a plurality of reciprocating liquid im elling means, means for simultaneously reciprocating the same, a plurality of separate hydraulically actuated reciprocating means, se arate hydraulic connections between sai plurality of impelling means and said plurality of actuated means, respectively, through which the latter are individually reciprocated, and means for arresting the motion of said actuated means prior to the completion of each stroke ofsaid connected'impelling means, respectively. 7

v 5. In a multi le hydraulic drive system the combination 0? a plurality of liqmd impelling means, means for simultaneously driving the same,'a plurality of separate hydraulically actuated means, separate hy-r draulic connections through which each of saidlast named means is individually driven. by one of said plurality of impelling means,

le stop for limiting the extentfof movement of each of said actuated 9 means.

v 6. In a multiple hydraulic drive system the combination of a plurality of liquid lmpelling means, means for simultaneousl driving the same, means for controlling the extent of movement of said impelling means collectively, a plurality of hydraulically actuated means each driven by one of said pluralit of.

1m lling means, and means for control in the extent of movement of said plurality o actuated means individually.

7.- In a multiple hydraulic drive system the combination of a plurality of liquid 1m(pelling means, means for simultaneously riving the'same, a plurality of hydraulically actuated means, separate hydraulic connections through which said' last named means are individually driven by said plurality of impelling means, respectively, means for revers; ing the direction of motion of said impelling means to thereby reverse the motion of said actuated means, and adjustable stops for limiting the extent of movement of said actuated means" in both directions of motion.

v 8. In a multiple-hydraulic drive system the combination of a plurality of li uid impelling means, means for simultaneous y driving the same at regulated rates, means for regulating the rate and extent of movement of said impelling means, a plurality of hydraulically actuated means each driven by one of said plurality of impelling means at rates corresponding to the rate of movement of said impelling means, and adjustable stops for individually limiting the extent of movement of said actuated means.

'9. In a multiple hydraulic drive system the combination of a plurality of li uid impelling means, means for simultaneous y driving the same at regulated rates, means for automatically regulating the rate of movement of said impelling means, and a plurality of hydrauli- I callyactuated means each driven by one of sai plurality of impelling'means at rates corresponding to the rate of motion of said impelling means. 7 3

10. In a multiple hydraulic drive system the combination of a lurality of liquid impelling means, means or driving the same at regulated rates, means responsive to the movement of said driving means for automatically varying the rate of movement of said impelling means, and a plurality of hydraulically actuatedmeans each driven by one of said plurality of impelling means at 7 rates corresponding to the rate of movement of said impelling'means. 4

11. In a multiple h draulic drivesystem the combination of a pluralit of liquid impelling means hydraulic. rivin m'eans therefor inclu 'ng a variable disp acement pump, means for varying pump dis lacement to vary the rate of movemento? said im lling means, and a plurality of hydraulidy actuated means each drivenby one of sai plurality of impellingmeans at rates corresponding to th'e'rate of movement of said impelling means.

7 12. In a multiple ,hydraulic system thecombination of a plurality of liquid impelling means, hydraulic drivin means therefor including a variable disp acemen't' pump, means responsive to the action of said driving means for regulating dump displacement, a plurality of hydraulically actuated means each driven by one of said impelling means, and means for individually controlling the extent of movement of said plura'hty of actuated means.

13. In a multiple hydraulic system the, combination of a, lurality of liquid impellin means, hy raulic drivin means there or including a variable disp acement pump, means for regulating pump displacement to regulate the rate of movement of said impelling means, a plurality of hydraulicall actuated means each individually driven by one of said impelling means, and means for controlling the extent of movement of each of said actuated'means'.

14. In a multiple hydraulic system the combination of a plurality of liquid impelling means, hydraulic driving means there'- for including a variable displacement pump, a pluralit of hydraulically actuated means, an individual hydraulic connection between each of said impelling means and one of said actuated means through which the latter are driven, positive stops for arresting the movement of said .actuated means, and liquid escape means within said connections permitting continued action of said impelling means after said actuated means have stopped.

15. In a multiple hydraulic system the combination of a plurality of liquid impelling means, means for driving the same in either direction, a plurality of hydraulically actuated means, a. separate, reversible flow hydraulic'ci rcuit between each of said impelling means and one of said actuated means through which the latter are driven, means including a check valve associated with one side of each of said circuits for supplying liquid under low pressure thereto, means including a check valve associated with the other side of,each of said'circuits for permitting the -escape of liquid therefrom, and means for maintaining said last namedcheck valves closed during operation of said actu- 17; In a hydraulic drive the combination sages therein, a pintle of a liquid impeller, hydraulically actuated means, and a flexible llquid conducting connection between said impeller and means throughwhich the latterisdriven, said connection comprising a pair of links each having a pair of separate liquid conducting pasforming a pivotal connection between said links and having a pair of separate passages therein, side ports in said pintle each communicating with one of said pintle passages and with one of said passages in one of said links, and additional side ports in said pintle each communicating with one of said pintle passages and with one of said passages in the other of said links.

18. In a machine tool or the like the combination of a rotary work holder, a tool support operating to cause the tool to follow the work during rotation of said holder, and a hydraulically actuated feed mechanism for the tool for advancing the tool into the work during movement of said holder and support.

19. In a machine tool or the like the combination of a rotary work holder, a plurality of separate tool supports operable to cause the supported tools to follow different portions of the work during rotation of said holder, and hydraulically actuated feed mechanisms for simultaneously advancing the tools into the work during movement of said holder and work supports.

20. In a machine tool or the like the combination of a rotary work holder, a pluralityof separate tool supports operable to cause its supported tools to; follow difierent parts of the work duringrotation of said holder,

a hydraulically actuated feedmechanism for each tooli movable with its support, and means including a variable delivery pump for efiectingthe simultaneous operation of said feed mechanisms at predetermined rates.

21. In a machine tool or the like the combination of a plurality of separate feed mechanisms, hydraulically actuated means for driving each'feed mechanism, a variable displacement pump, and a hydraulic power transmission system between said pump and means for efiecting the simultaneous operation of said feed mechanisms at rates corresponding to pump displacement.

22. In a multiple hydraulic drive the comf bination of a plurality of separate hydraulically actuated means, a variable displace-' ment "pump, and a hydraulicpower transmission system between said pump and means for effecting the simultaneous operation of said means at rates corresponding to pump displacement. v

23. In a multiple hydraulic drive the combination of a plurality of separate hydraulically actuated means, "a variable displacement pump, a hydraulic power transmission s stem between said pump and means for simultaneously driving said separate means at rates corresponding to pump displacement,

operatively related to .all of the pumps to operate the same, and means common element.

25. In a machine tool, a series of tool holders and means for feeding the same, comprising a series of operating members, a series of cylinders, and pistons in the cylinders coupled to drive the said operating members, a series of pump elements arranged to supply fluid to the series of cylinders so as to move 1 the pistons therein, a common element coupled mechanically to all of the pumps to o eratethe same, and means for driving e common element. a

26. In a machine tool, a series of tool holders and means for feeding the same, comprisfor driving the ing a series of operating members, a series of cylinders having pistons therein, said pistons 8Q being coupled to the operatlngmembers, a sec ond series of cylinders having pistons therein, a common operating member for said last named pistons, and connectionsfrom the cylinders of the second series to the cylinders of the first series so arranged that a fluid set, in motion by the pistons of the second series enters the cylinders of the first series and op= crates the same.

27. In a machine tool, a series of tool holding a series ofoperating members, a series of cylinders, and pistons in the cylinders co u-' pled to drive the said operating members, a series of pump elements arranged to supply fluid to the series of cylinders so as to move the pistons therein, a common element coupled mechanically to all of the pumps, to operate the same, and means for driving the common element,. said means comprislng'a cylinder and a piston therein connected to the common element, and means for supplying fluid under pressure to operate the piston last named. w i 28. In a machine tool, a series of tool hold ing a series of operating members, a series of c linders, and pistons in the cylinders coupled to drive the said operating members, a series of pump elements arranged to supply fluid to the series of cylinders so as to move the pistons therein, a common element coupled mechanically toall of the pumps to operatethe same, and means for driving thecommon element, said means comprising a i cylinder and a piston therein connected to ers and means for feeding the same, comprisers and means for feeding the same, comprisfluid at varylng opfluid to the series of cylinders so as to move the pistons therein, a common element coupled mechanically to all of the pumps to operate the same, and means for driving the so common element, said means comprisin a cylinder and a piston therein connecte to the common element, and means for supplying fluid under ressure to operate the piston last named, sai means being of a type to deliver a constant flow of fluid at varying opposing pressures, said tool holders, operating members, cylinders and pistons being arranged as a series of tool operating systems said systems as 'a whole movably mounte with relation to said pumps, and flexible conduits connecting the pumps to said cylinders.

30. In a machine tool, a series of tool holders and means for feeding the same, comprising a series of operating members, a series of 3 cylinders, and pistons in the cylinders coupled to drive the said operating members, a series of pump elements arranged to supply fluid to the series of cylinders so as to move the pistons therein, a common element coupled mechanically to all of the pumps to operate the same, and means for driving the common element, a control means for the said machine tool, and connections from said common member to operate said control means automatically. 31. In a machine tool, a series of tool holders and means for feeding the same, comprising a series ofoperatin members, a series 1 of cylinders, and pistons 1n the cylinders coupled to drive the said operating members, a series of pum elements arranged to supply fluid tothe series of cylinders so as to move the pistons therein, a common element operatively related toall of the pumps to operate the same, and means for driving the common element,. each of said tool holders having positive stops. 32. In a-machine tool, a series of tool holders and means for feeding the same, compris-- ing a series ofoperating members, a series of c linders, and pistons in the cylinders couple to drive the said operating members, a.

series of pump elements arranged to supply 4 fluid to the series of cylinders so as to move .125

the pistons therein, a common element coupled mechanically to all of the pumps to operate the same, and means for driving the common element, a control means for the said machine tool, and connections from said common member to operate said control means. automatically, each of said tool holders having positive stops.

33. An hydraulically operated system for the operation of a series of working members of a machine tool comprising a source of hydraulic pressure of a type to deliver a constant flow of liquid at varying pressures, a master cylinder to which liquid is delivered from said source, and a series of separate hydraulic power delivery systems, one for each working member, each of said separate systems deriving its energy from said master cylinder. 34. An hydraulically operated system for the operation of a series of working members of a. machine tool comprising a source of hydraulic pressure of a type to deliver a con stant flow of liquid at varying pressures, a master cylinder to which liquid is delivered from said source, and a series of separate hydraulic power delivery systems, one for each working member, each of said separate systems deriving its energy from said master :5 cylinder, said power delivery systems each,

comprising a hydraulic cylinder and piston for each working member and movable therewith, and flexible conduit means whereby hydraulic pressure is delivered to each of said cylinders.

In' 'tness whereof, I hereunto subscribe my name this 11th da of February, 1928. J OHN P. FERRIS.