US3173313A - Hydraulically controlled indexing mechanism for turntables - Google Patents

Description

it is necessary to maintain such high torque ratio in the low speed range. In the higher speed ranges, the present transmission will effectively perform its intended function since, as the speed of the driving shaft reaches a relatively high level, the speed ratio through the fluid coupling levels off and approaches a direct one-to-one drive ratio, while the speed ratio through the variable pitch pulley assembly 12 likewise levels off and approaches such a direct drive ratio, this being due to the action of centrifugal force acting upon the steel balls 124 and causing the two pulley sections 102 and 104 to approach each other and increase the effective driving diameter of the pulley assembly 86. In this high speed range however, the transmission as a whole remains sensitive to slight variations in speed ratio and thus, when the transmission is put to such use as the operation of winding machines and the like, the constant incremental increase in drum or reel diameter which ordinarly has the effect of normally decreasing the torque applied to the winding drum, causes a corresponding incremental degree of countertorque to be applied to the drum. This degree of countertorque is not immediately sensed by the variable pitch pulley assembly 12 but is transmitted through the assembly to the fluid coupling and results in a degree of slippage between the impeller and turbine vanes so that the output shaft, i.e. the connector shaft 64, decreases its speed slightly. This decrease in speed is then reflected in the variable pitch pulley assembly by the operation of the driving pulley assembly 86, the decrease in rotative speed of which causes the steel balls 3.24 to lose a degree of their centrifugal force so that the tension of the belt 92 will effect a corresponding decrease in effective driving pulley diameter, thus increasing the torque output of the transmission as a whole.

It is deemed unnecesary to set forth the mode of operation of the transmission assembly for additional environments thereof, it being suflicient to state that, generally speaking, variations in load at the output shaft 16 are first transmitted through the variable pitch pulley assembly 12 to the fluid coupling 10 and the consequent change of operating in this fluid coupling is then effective to modify the operation of the variable pitch pulley assembly. At any given rotative speeds of the drive shaft and driven shaft respectively, and at any given output load, the two principal assemblies 11) and 12 may be said to be in a condition of equilibrium, this condition remaining effective until there is a change in input speed or output load.

The invention is not to be limited to the exact arrangement of parts herein described or shown in the accompanying drawings as various changes in the details of construction may be resorted to without departing from the spirit of the invention. For example, in the exemplary form of the invention shown and described herein, the fluid coupling 10 precedes the variable pitch device in the series relationship in which they are coupled. It is however within the purview of the invention that the variable pitch device shall precede the fluid coupling in the series relationship. Still further, it is contemplated that the fluid coupling and variable pitch device may assume forms other than those disclosed herein. For example, this coupling may be of the viscous shear type or it may assume the form of an electromagnetic or eddy current coupling if desired. These and various other forms of slip devices are capable of use to satisfy the requirements of certain installations. Additionally, other forms of variable pitch devices than the one illustrated and described herein may be employed if desired. A wide variety of Reeves type mechanisms are available for use whether the output section thereof is spring loaded as shown herein 'or whether it be provided with other means for eliminating belt slack. Therefore, only insofar as the invention has particularly been pointed out in the accompanying claims is the same to be limited.

Having thus described the invention, what I claim and desire to secure by Letters Patent is:

1. An automatic transmission mechanism for establishing a driving connection between a driving shaft and a driven shaft arranged in parallelism, said mechanism comprising, in combination with said shafts, a fluid composite coupling including an annular rotatable casing operatively connected to the driving shaft in driven relationship and constituting the driving element of the fluid coupling, and a turbine disposed within said casing and constituting the driven element of the fluid coupling, a composite centrifugally operable variable speed change device including a drive sleeve coaxial with the driving and driven elements of the fluid coupling, a connecting shaft extending coaxially between the driven element of the fluid coupling and the drive sleeve and projecting through the latter, a fixed bearing support for said connecting shaft disposed between the fluid coupling and the speed change device, through which the connecting shaft projects, and in which it is rotatably journalled, means fixedly securing the connecting shaft to the driven element of the fluid coupling in driving relationship, means establishing a splined driving connection between the connecting shaft and the drive sleeve, said speed change device further including a split pulley on said drive sleeve and having a pair of pulley sections relatively movable toward and away from each other, said pulley sections defining therebetween a V-groove of variable width for reception therein of a V-belt whereby the effective diameter of the pulley is a function of the groove width, means connecting at least one of said pulley sections and drive sleeve for rotation in unison, centrifugally operable means responsive to increasing and decreasing increments of speed of said drive sleeve for causing relative movement of the pulley sections toward and away from each other respectively to decerase and increase the V-groove width respectively, a compensating split pulley on said driven shaft, and a V-belt operatively connecting the two split pulleys in driving relationship, said bearing support constituting the sole supporting means for said fluid coupling, the connecting shaft and the speed change device exclusive of the compensating split pulley and adjacent portions of the V-belt.

2. An automatic transmission mechanism for establishing a driving connection between a driving shaft and a driven shaft arranged in parallelism, said mechanism comprising, in combination with said shafts, a composite fluid coupling including an annular rotatable casing operatively connected to the driving shaft in driven relationship and constituting the driving element of the fluid coupling, and a turbine disposed within said casing and constituting the driven element of the fluid coupling, said casing being formed with an internal reentrant hub, a central axial shaft projecting through said hub and operatively connected to the turbine in driven relationship, the rear end of said central axial shaft being formed with a socket therein, a composite centrifugally operable variable speed change device spaced axially and rearwardly from the composite fluid coupling and including a drive sleeve coaxial with the driving and driven elements of the fluid coupling, a connecting shaft having its forward end secured in said socket and projecting rearwardly through said drive sleeve, a fixed bearing support for said connecting shaft and disposed between the fluid coupling and the speed change device, said connecting shaft projecting through said bearing support and being rotatable therein, means establishing a spline connection between the rear end region of the connecting shaft and said drive sleeve for imparting rotation movement to the latter from the former, said speed change device further including a split pulley on said drive sleeve, said split pulley including an axially fixed pulley section and an axially shiftable pulley section movable toward and away from the axially fixed pulley section, said pulley March 16, 1965 G. w. TAYLOR 3,173,313

HYDRAULICALLY CONTROLLED INDEXING MECHANISM FOR TURNTABLES Filed May 51, 1962 2 Sheets-Sheet 2 Ava/v70? G. W Tay I or United States Patent HYDRAULICALLY CQNTROLLED INDEXING MECM FOR TURNTABLES George William Taylor, Wells, Kent, England, assignor to Poligram Casting Co. Limited, Tunbridge Wells, Kent, England, a company of Great Britain Filed May 31, 1962, Ser. No. 199,173v

6 Claims. (Cl. 74817) This invention relates to turntables and has particular reference to turntables for supporting several sets of apparatus to be brought sequentially by rotation of the turntable into a predetermined location.

According to the present invention, a turntable includes an indexing mechanism comprising a carriage movable along a path lying tangentially with respect to a circle described about the axis of rotation of the turntable, a lever pivotally mounted on the carriage so as to swing in a horizontal plane and about a point lying on the line of tangential movement, means for coupling the turntable to, and uncoupling the turntable from, the lever and an arrangement for reciprocating the carriage along its path of movement.

Preferably, the means for reciprocating the carriage comprises a fluid operated piston and cylinder assembly, the carriage being operatively connected to the movable member of the assembly.

The turntable may be equipped with a locking device which locks the table against movement when the latter is uncoupled from the lever. Desirably, the locking device is interlocked with the means for coupling the uncoupling in such manner that, at no time, is the table uncoupled from the lever and not locked by the locking device.

Fluid-operated braking means may be fitted adjacent the piston and cylinder assembly to assist in reducing the speed of the turntable prior to the latter being brought to a standstill at the end of the stroke of the assembly.

In one embodiment of the invention, the turntable is coupled to the lever by means of a driving pin moved by a fluid operated piston and cylinder assembly mounted on the lever. That assembly includes limit valves which interlock it with another assembly for operating a locking pin forming part of the locking device. Both pins cooperate with recesses in blocks mounted on the turntable, for example, secured to the underneath surface thereof. The recesses in the blocks may be of conical form so that the pins are then self-centering and remain so despite wear.

By way of example only, an embodiment of the invention will now be described in greater detail with reference to the accompanying drawings of which:

FIG. 1 is a plan view of part of the indexing mechanism of the embodiment,

1G. 2 is a section on the line IIlI of FIG. 1 and includes part of the turntable, and,

FIG. 3 shows the pneumatic circuit of the embodiment in block schematic form.

The turntable is of annular form when seen in plan and is supported upon suitable bearings enabling it to rotate about a central vertical axis. The bearings lie between that axis and the inner circumference of the annulus so that the central opening is left clear for electrical leads, supply pipes or other apparatus which may have to be connected to apparatus on the surface of the turntable. Secured to the undersurface of the turntable and equi-spaced round the axis of rotation are six blocks apertured centrally to engage locking and driving pins in a manner described later. Thus, in FIG. 2, is shown part of the turntable 1 and two, 2, 3, of the six apertured blocks. The apertures in the blocks are of conical form.

"ice

Located beneath the turntable is a framework supporting a main pneumatically operated piston 4 and cylinder 5 assembly orientated so that the piston 4 can be extended and retracted along a line which is a tangent to a circle drawn about the axis of rotation of the turntable through the apertures in the blocks. Secured to the outer end of the piston is a carriage 6 movable along spaced guides 7, 8 and carrying parallel spaced levers 9 pivotally mounted on the carriage. The levers are fixed to the ends of a vertical pivot pin 10 rotatably mounted in a hearing sleeve 11 on the carriage. The arms of the levers are of about equal length and at one end the levers carry a tubular guide 12 and at the other a pin 13 whose ends travel in arcuate slots 14 in the framework of the carriage. The arcuate slots lie across the line of movement of the piston of the main assembly as can be seen in FIG. 1.

On each side of the cylinder 5 of the main assembly is a pneumatic brake comprising a piston-cylinder-assembly 15 whose piston carries a butler pad 16 for engagement with a shoulder on the carriage.

As can be seen in FIG. 2, the tubular guide 12 supports, at its lower end, a pneumatically operated piston and cylinder assembly 17 to whose piston 18 is secured a driving pin 19.

Also located beneath the turntable is a locking device comprising a locking pin 20 movable vertically along a suitable guide 21 by a pneumatic piston-cylinder assembly 22. The locking device is positioned such that the locking pin can be projected upwardly at an appropriate moment to engage the aperture in one of the blocks 3 mentioned above.

The length of stroke of the piston 4 is selected in accordance with the number of blocks and in the embodiment each of the six blocks is engaged in turn by the driving pin 19 at one end of the stroke and disengaged at the other end. Thus, no pivotal movement of the lever 9 is necessary between the disengagement of one block and the engagement of a succeeding block, so long as the machine is started with the engaged block in a position such that the chords connecting the are through which said engaged block will be driven is parallel to the path of travel of the piston.

The various piston and cylinder assemblies are provided with control valves which are operated in a manner now to be described withreference to FIG. 3 which shows the pneumatic circuit in block schematic form, all valves being shown in their normal, unoperated positions.

Associated with the piston 4 are limit switches actuating changeover valves 23 and 24 arranged as shown at opposite ends of the stroke of the piston. Valve 24 may also be operated by compressed air. The flow of compressed air to the cylinder 5 is controlled by a changeover valve 25 operated by pneumatic pressure supplied via either start valve 26 or a control valve 27 located at one end of the stroke of the piston actuating the driving pin 19. At the other end of the stroke of that piston is another control valve 28. Associated with the piston actuating the locking pin 20 is a control valve 29, the supply of compressed air to cylinder assembly 22 of the piston being controlled by a pneumatic pressure operated valve 30. A similar pressure operated valve 31 controls the supply of compressed air to cylinder assembly 17.

In the flow lines from valve 25 to the cylinder 5 are pressure operated valves 32 and 33 operation of which is under the control of a manually operated emergency stop control 34 and a reset control 35. Operation of control 34 closes valves 32 and 33 regardless of the position of the piston 4 thereby bringing the latter to a standstill. Movement is resumed by operation of the reset control 35. FIG. 3 also shows the pneumatic brakes 15 to the pneu- '3 matic circuits of which is coupled an adjustable pressure regulator valve 36 which determines the resistance otfered by the brakes. The effective resistance is indicated by a pressure indicator 37. Also included -in the pneumatic circuit are how regulators indicated diagrammatically at 38.

Initially,"thedrivingpin 19 isextended into the aperture in-one of the blocks on the undersurfaceofthe'turntable whilst theloc king-p in 2t) is-disengaged and in this position piston 4 of cylinders is in its extended position. Actuationof the maincontrol valve 26 admits compressed air to-the cylinder '5, the piston 4 of which startsto retract thereby moving the carriage 6 along the guides 7,'8-and the turntablerotates through 60. T hepiston 4 is brought to a standstill at the end of its stroke by pneumatic brakes and limit valve .23 is operated. ln that position shown in FIG. 3, the locking pin Ztlisdirectly below one of the apertured blocks. The limit valve '23 alsooperates valve 30 which permits compressed air to flow to-the pistoncyiinder assembly 22 of the locking pin and the latter s isad-vanced into the aperture block 3 -above it. Completion ofthat movement operates lihiit valve 29 which actuates valve 31 of the piston-cylinder assembly 17 of the driving pin which is then withdrawn by the application of compressed air to cylinder 17. The turntable is 4 now locked so that when the cylinder 5 is energised -by valve27 operating valve its piston 4 -is extended.

At the other end of the stroke of piston 4, valve 24 is operated and the sequence 'is reversed. Driving pin 19 is moved into engagement -with an apertured block 2 after .which locking pin 20 is withdrawnand the fullsequence may berepeated by-opeiationof control valve 26.

During movement of the turntable the piston of the inain assembly moves linearly along a-path tangentialto a circle which is described about the axis of -rotation of the turntable and the pivot point 10 of the levers 9 follows thesame path. The .driving pin 19 however follows an arcuate path beginning at one end of said tangential path-and ending at theotherend of said tangential path so .that the levers pivot .during movement of the carriage and are .guided during that movement by the guide pin 13 which travels back and forth along the armate slots 14.

Just before the end of the stroke of the pistonof the main assembly, the carriage shoulders engage the butter blocks 16 on the pneumatic brakes '15 thereby slowing the turntable preparatory :to the latter being brought to a standstillat the .end of a strokeof a piston. The instant of engagement of butter blocks and shoulders occurs when the lever .is in linewith the pistonof the main assembly.

The sequence described above can be made torepeat either automatically or under a manually operable control.

It will be appreciated that at no time is the turntable free of both pins and this ensures greater accuracy of indexing and control of movement. The linear movement of the piston of the main assembly as well as of the pivotal axis of the lever is translated by the latter into an arcuate movement of the driving pin.

The main piston-cylinder assembly may be hydraulically operated asmay the other assemblies or alternatively some other form of drive for the carriage may be used. Pneumatic operationis particularly suitable in the case of very heavy turntables which also require pneumatic brakes described above although the latter may not be needed for turntables of lighter weight.

I claim:

1. A turntable assembly comprising, in combination, a turntable, a linear actuator including a movable member .and fixed guide means restricting said movable member to rectilinear motion along a path tangent to a circle concentric with the turntable, a plurality of sockets mounted on the turntable adjacent the periphery thereof in a ring concentric with said turntable and spaced from each other by a chord equal to the length of stroke of the movable member, a lever pivotally mounted upon the movable member to turn about an axis parallel to the axis of the turntable, and a driving pin mounted on the lever in a position which is in alignment with one of said sockets at one limit of the stroke of themovable membensaid pin being mounted for sliding movement relative to said lever which brings it into driving engagement with said aligned socket so asto propel said aligned socket during the subsequent stroke of the movable member, along an arc of said ring whose chord is equal in length and par allel to the stroke of said movable member.

2. A turntable assembly comprising, in combination, a turntable, a linear actuator including a movable member and fixed guide means restricting said movable member to rectilinear motion along a path tangent to a circle concentric with the'turntable, a plurality of sockets mounted on the turntable'adjacent the periphery thereof in a ring concentric with saidturntable and spaced from each other by a chord equal to the length of stroke of the movable member, a lever pivotally mounted upon the actuator to turn about an axis parallel to the axis of the turntable, a driving pin mounted on the lever in a position which is in alignment with one of said sockets at one limit of the stroke of the actuator, said pin being mounted for sliding movement relative to said lever which brings it into driving engagement with said aligned socket so as to propel said aligned socket during the subsequent stroke of the actuator, along an arc'of saidring whose chord is equal in length to the stroke of said actuator, and a slidable pin mountedona stationary portion of said assembly for engagement with the sockets whereby the turntable may beheld against rotation.

3. A turntable assembly comprising, in combination, a turntable, a linear actuator including a movable member and fixed guide -means restricting said movable member to rectilinear motion along a path tangent to a circle concentric with the turntable, a plurality of sockets mounted on the turntable adjacent the periphery thereof in a ring concentric with said turntable and spaced from each other by a-chord equal to the length of stroke of the movable member, a lever 'pivotally mounted upon the -movable member to turn about an axisparallel to the axis of the turntable, a driving pin mounted on the lever in a position which is in alignment with one of said sockets at one limit of the stroke of the movable member, said pin being mounted for sliding movement relative to said lever which brings itinto driving engagement with said aligned socket-soas to propel-said aligned socket during the subsequent stroke of the movable member, along an arc of said ring whose chord is equal in length and parallel to the stroke of said movable member, and a brake whereby the turntable is brought to rest after rotation by the movable member.

4. A turntable assembly comprising, in combination, a turntable, alinear actuator including a movable member and fixed guide means restricting said movable member torectilinear motion along a path tangent to a circle concentric with the turntable, a plurality of sockets mounted on the turntable adjacent the periphery thereof in a ring concentric with said turntable and spaced from each other by a chord equal to the length of stroke of the movable member, a lever pivotally mounted upon the movable member to turn about an axis parallel to the axis of the turntable, a driving pin mounted on the lever in a positionwhich'is in alignment with one of said sockets at one limit of the stroke of the movable member, said pin being mounted for sliding movement relative to said lever which brings it into driving engagement with said aligned socket so as to propel said aligned socket during the subsequent stroke. of the movable member, along an arc of said ring whose chord is equal in length and parallel to the stroke of said movable member, a slidable pin mounted on a stationary portion of the assembly for engagement with the sockets whereby the turntable may be held 5 against rotation, and a brake whereby the turntable is brought to rest after rotation by the movable member.

5. A turntable assembly comprising, in combination, a turntable, a linear actuator including a movable member and fixed guide means restricting said movable member to rectilinear motion along a path tangent to a circle concentric with the turntable, a plurality of sockets mounted on the turntable adjacent the periphery thereof in a ring concentric with said turntable and spaced from each other by a chord equal to the length of stroke of the movable member, a lever pivotally mounted upon the movable member to turn about an axis parallel to the axis of the turntable, a driving pin mounted on the lever in a position which is in alignment with one of said sockets at one limit of the stroke of the movable member, said pin being mounted for sliding movement relative to said lever which brings it into driving engagement with said aligned socket so as to propel said aligned socket during the subsequent stroke of the movable member, along an arc of said ring whose chord is equal in length and parallel to the stroke of said movable member, a slidable pin mounted on a stationary portion of said assembly for engagement with the sockets whereby the turntable may be held against rotation, and a hydraulic control system for actuating said pins which ensures that at least one socket is always engaged by one of the two pins.

6. A turntable assembly comprising, in combination, a turntable, a linear actuator including a movable member and fixed guide means restricting said movable member to rectilinear motion along a path tangent to a circle concentric with the turntable, a plurality of sockets mounted on the turntable adjacent the periphery thereof in a ring concentric with said turntable and spaced from each other by a chord equal to the length of stroke of the movable member, a lever pivotally mounted upon the actuator about an axis parallel to the axis of the turntable, a driving pin mounted on the lever in a position which is in alignment with one of said sockets at one limit of the stroke of the movable member, said pin being mounted for sliding movement relative to said lever which brings it into driving engagement with said aligned socket so as to propel said aligned socket during the subsequent stroke of the actuator, along an arc of said ring whose chord is equal in length to the stroke of said movable member, a slidable pin mounted on a stationary portion of said assembly for engagement with the sockets whereby the turntable may be held against rotation, a brake whereby the turntable is brought to rest after rotation by the movable member, and a hydraulic control system for actuating said slidable pins which ensures that at least one socket is always engaged by one of the two pins.

References Cited by the Examiner UNITED STATES PATENTS 2,560,475 7/51 Rehnberg et a1. 74116 2,832,235 4/58 Denman 74-1255 X 2,948,166 8/60 Purse et a1. 74822 3,120,132 2/64 Lafay 74---128 X BROUGHTON G. DURHAM, Primary Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,173,313 March 16, 1965 George William Taylor It is hereby certified that err ent requiring correction and that the said Letters Patent shoal-d read as corrected below.

In the grant, lines 2 and 12, and in the heading to the printed specification, line 5, for "Poligram Casting Co,

Limited", each occurrence, read Polygram Casting Co. Limited Signed and sealed this 27th day of July 1965.

(SEAL) Attest:

ERNEST W. SWIDER EDWARD J. BRENNER Attesting Officer Commissioner of Patents or appears in the above numbered pat-.-

Claims (1)

1. A TURNTABLE ASSEMBLY COMPRISING, IN COMBINATION, A TURNTABLE, A LINEAR ACTUATOR INCLUDING A MOVABLE MEMBER AND FIXED GUIDE MEANS RESTRICTING SAID MOVABLE MEMBER TO RECTILINEAR MOTION ALONG A PATH TANGENT TO A CIRCLE CONCENTRIC WITH THE TURNTABLE, A PLURALITY OF SOCKETS MOUNTED ON THE TURNTABLE ADJACENT THE PERIPHERY THEREOF IN A RING CONCENTRIC WITH SAID TURNTABLE AND SPACED FROM EACH OTHER BY A CHORD EQUAL TO THE LENGTH OF STROKE OF THE MOVABLE MEMBER, A LEVER PIVOTALLY MOUNTED UPON THE MOVABLE MEMBER TO TURN ABOUT AN AXIS PARALLEL TO THE AXIS OF THE TURNTABLE, AND A DRIVING PIN MOUNTED ON THE LEVER IN A POSITION WHICH IS IN ALIGNMENT WITH ONE OF SAID SOCKETS AT ONE LIMIT OF THE STROKE OF THE MOVABLE RELATIVE TO SAID PIN BEING MOUNTED FOR SLIDING MOVEMENT RELATIVE TO SAID LEVER WHICH BRINGS IT INTO DRIVING ENGAGEMENT WITH SAID ALIGNED SOCKET SO AS TO PROPEL SAID ALIGNED SOCKET DURING THE SUBSEQUENT STROKE OF THE MOVABLE MEMBER, ALONG AN ARC OF SAID RING WHOSE CHORD IS EQUAL IN LENGTH AND PARALEL TO THE STROKE OF SAID MOVABLE MEMBER.

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