US3187529A

US3187529A - Wire drawing machine

Info

Publication number: US3187529A
Application number: US134313A
Authority: US
Inventors: Edwin J Mcilvried
Original assignee: Morgan Construction Co
Current assignee: Siemens Industry Inc
Priority date: 1961-08-28
Filing date: 1961-08-28
Publication date: 1965-06-08
Anticipated expiration: 1982-06-08
Also published as: GB931178A

Description

June 8, 1965 E. J. MGILVRIED WIRE DRAWING MACHINE 5 Sheets-Sheet l Filed Aug. 28. 1961 INVENTM Edu/in mcllv'rieal BY RMA-u. cmsuwl H orneys June 8, 1965 E. J. MclLvRlED WIRE DRAWING mcanm 5 Sheets-Sheet 2 Filed Aug. 28. 1961 NLM lll/[lll V INVENTOR. Edu/in mclluried. BYPW, wsdl.

H orneys June 8, 1965 E. J. M'crLvRrEx-J 3,187,529'

' WIRE mmm@ MACHINE:

Filed Aug; 28. 1961 5 sheets-sheet a INVENTOR. Edu/in JF [Zzfried E. J. MclLvRlED WIRE DRAWING MACHINE June 8, 1965 5 Sheets-Sheet 4 Filed Aug. 28, 1961 l, INVENToR.

772C IZv/rz'ed Cumul. EAN!) Edu/m By'umn H o'rneys June 8 1965 E. J. MClLvRn-:D

WIRE DRAWING MACHINE 5 Sheets-Sheet 5 Filed Aug. 28, 1961 INVENTOR. Edwin 771 ZUTI'ecl Rauw, emma.. w

OTTLeyS United States Patent O 3,187,529 DRAWING MACHlNE Edwin I. Mcilvried, Cuyahoga Falls, Ohio, assigner to Morgan Construction Company, Worcester, Mass., a corporation of Massachusetts Filed Aug. 28, 1961, Ser. No. 134,313

3 Claims. (Cl. 72-24) This invention relates in general to a wire drawing Inachine and more particularly to an improved apparatus arranged to regulate block speeds through tension created on wire passing between spaced rotatable blocks.

In a wire drawing machine of the continuous nouaccumulative type, it is necessary to regulate the speed of the various blocks, particularly to maintain the optimum tension on either side of the dies interposed between the blocks. Regulating this tension between a die and the preceding block has considerable effect -on the quality of the wire drawn and on the life of the die. It is obvious to anyone skilled in vthe art that excessive tension will result in breakage or minute fractures in the wire and insuflicient tension allows slipping around the forwarding block, destroying the wire coating and injuring the peripheral surfaces of the block. One system that'is used in the industry for regulating block speeds involves the use of the so-called dancer roll. In this system, thewire in passing from a block to the following die passes around a single pulley or wheel which is mounted on the end of a pivot arm. The tension in the wire allows the wheel -to move about the pivotal axis of the arm to regulate the speed of block drive mechanisms. The arm on which the conventional dancer roll is mounted, however, must be of suicient length to translate movement ofthe pulley to the regulating equipment, and it is necessary that these pulleys be disposed between the blocks of a multiple block machine, the overall length of the machine becomes prohibitive in an eHicient modern day wire drawing operation.

A further disadvantage with the conventional control arm results from the counter balancingof the pivot arm by a spring so that an increase in the angle of the arm increases the tension on the spring which affects the tensioning of the wire.

Furthermore, t-he particular arrangement of the dancer rolls with respect to the blocks presents a problem in the threading operation particularly when the wire is. of a large diameter. As a result of these factors, the length of the block table may be very long and the machine unduly large. These and other difficulties experienced with the prior art devices have been obviated in a novel manner by the present invention.

It is one object of this invention to provide a wire drawing machine having a novel means for controlling block speed-s.

Another object of this invention is the provision of a wire drawing machine having a novel dancer roll means for regulating the tension in the wire.

A yfurther object of the present invention vis the provision of a Wire drawing machine having a dancer roll arrangement such that the blocks may be closely spaced together to obtain a relatively short wire drawing machine.

It is another lobject of the instant invention `to provide a wire drawing machine having a dancer roll permitting the use of a relatively'large loop allowing more sensitive response of an individual block motor.

1- A still further object of this invention is the provision of a wire drawing machine having a dancer roll arrangel ment which is relativelyeasy to string.

It isa still further object of the present invention to provide a wire drawing machine having block speed regulating means which permits regulating the amount of ten,- sion on the wire.

rAnother object of the invention is the provision of'tv ICC wire drawing machine having a motor speed regulating means arranged in such a way as to permit greater accessibility to the block speed regulating mechanism.

With these and other objects in view, as will be apparent to those yskilled in the art, the invention resides in the combination of parts set forth in the specification and covered by the claims appended hereto.

The character of the invention, however, may be best understood by reference t-o one of its structural forms as illustrated by the accompanying drawings in which:

yFIG. 1 is a plan view of a wire drawing machine embodying .the principles of the present invention;

FIG. 2 is a sectional view of the invention taken on the line II-II of FIG. `l;

FIG. l3 is a sectional view of the apparatus taken on the line III-III of IFIG. 2;

IFIG. 4 is a sectional view of the apparatus taken on the line lIV-IV of FIG. 2;

FIG. 5 is a sectional view of the apparatus taken on the line V-V of fFIG. 2;

FIG. 6 is a sectional View of the apparatus taken on the line VI-VI iFlG. 2;

FIG. 7 is a horizontal sectional view of the apparatus taken on the line VII- VII of FIG. 2; and

FIG. v8 is a view in perspective of a modified form of the guide means.

Referring first to FIG. l, wherein are best shown the general features of the invention, a wire drawing machine, indicated by the reference numeral 10, is shown as consisting of a series of linearly disposed blocks 11, 12, 13 and 14 mounted for rotation on vertical pivotal axes above a housing 15 having a horizontal work surface 16. Between the lblocks 11 and 12 is located a wire drawing die 17, while between the blocks 12 and 113 is located a die 18, and a similar die 19 located between the blocks .13 and 14. The block 11 is rotated by independent drive means, such as a motor 21 and a transmission 22. `In a similar way, the block 12 is rotated by a mot-or Z3 through a transmission 24, the block 13 is rotated by a motor 25 through a transmission 26, and the block 14 is rotated by a motor 27 through a transmission 28. The speed of each drive means is adjustably regulated by independent control means; for example, the motor 21 of the block 11 is provided with a control means 29, while the motor 23 of the block 12 is provided with a control means 31 and the motor 25 of the block 13 iS provided with a control means 32.

Referring to FIG. 2, it can be seen that the wire drawing machine, 10, in addition to having a housing 15 with its horizontal work surface 16, is provided with a rearwardly located support 33 in the form of a casing having a horizontal surface 34 and a vertical surface 35 facing toward the front or operators side of the machine. As iS shown in this ligure, the control means 29 regulating the speed of the drum 11 rests on the horizontal work surface 16 of the housing and consists of a fixed portion 36, a movable portion 37, and a guide 38. The fixed portion has a base 39 which is secured by bolt or other means t0 the forward portion of the horizontal work surface 16 and is provided with two

rotatable sheaves

41 and 42 superposed above each other. The movable portion 37 consists of a C-shaped carriage 43 on which are mounted two

rotatable sheaves

44 and 45 langularly disposed in relation' to each other for a purpose to be set forth hereinafter.

Referring to FIG. 3, it can be seen that the carriage 43 s supported on rail 46 mounted on the work surface 16, the rail-having a vertical surface 46 and surface 46" inclined at an, angle of approximately 45 from the horizontal, both surfaces extending from front to rear of the wire drawing machine. A roller 47 extends downwardly from the carriage 43 and engages the vertical surface of on the underside of the carriage 43 and rolls along the' inclined surface 46" of the rail46.

The guide 3S consists of a number of `articulated members, including a bracket 52 fastened to the corner formed by the intersection of the surfaces 3d and 35 of the support 33. Attached to-the bracket and allowing pivotal movement about a vertical hinge pin 53 is an intermediate member d having at its distal end a pair of transversely extending vertically spaced pins 57 and 53 defining pivotal axes for pairs of transversely spaced lever members and 56. The other end of the

lever members

55 and 56 are connected to a junction member 59 disposed between the pairs. of lever members and having upper and lower transversely extending pivot pins 61 and 62. Connecting the carriage 43 with the junction member 59 are pairs of

link members

63 and 64 disposed on either side of the junction member 59, outside of the lever members 55 .and 56, and pivotally secured to pins 65 and 66 at one end and at laterally spaced pivot pins 66 and 7tl-extending transversely through the carriage i3 at the other end. The pivot pins 65 and 66 herein described are fixed within the junction member 59 and are provided at their ends *with ball caps which ride in spherical pockets within the link members.

Referring to FIG. 4, there is illustrated the manner iny which the sheaves lll and 42 may be mounted in a fixed position on the base 39. The base is provided with a vertical shaft 69 on which are mounted ball bearings 71 and 72 axially spaced `from each other permitting independent rotation and which, in turn, carry the sheaves #l1 and 42, respectively. A wire guard 73 is mounted on the base 39 which extends partially around the sheave 42, butV does not rotate with it. A similar guard 74 is mounted on the shaft 69 and serves to partially enclose Vthe upper sheave 4l.

FIG. 5 shows the manner in which the

sheaves

44 and 45 are mounted in the movable portion 37. The carriage 43 is generally C-shaped having a vertical back member 77 .and a pair of spaced leg members 75'and 76 extending forwardly from the distal ends. On the lower leg 75', is, mounted a vertical shaft 78 carrying a ball bearing 79 on which the lower sheave 45 is horizontally mounted. Extending forwardly of thel back member 77 midway between the bottom leg 75 and the upper leg 76 is an .angularly extending supporting flange 8l which has an upstanding stub shaft 82 carrying a ball bearing 33 on which the sheave dd is mounted. The supporting flange 8l is provided with upstanding guards Si) partially surrounding the sheave 4d.

FIG. y6 vis 'a View in section of a portion of the guide 38 and illustrates the manner in which the pairrof levers 55 and 56 pass on either side of the junction member 59. and conected thereto by the pivot pins 61 and 62. 'It is apparent that the links 63 extend outside of the lever member 56 and allow relative movement therewith. In

both instances, the pivot pins 6l and 62 are fixed within f the junction member 59 and extend transversely thereto providing bearing surfaces for the lever'members 55 and 56. v

The actuating mechanism for the control means 29 is illustrated in FIGS.V 2 and 7 and includes a shaft 49 extending rearwardly from the frame t3 through the supporting panel andjhaving a coil spring 5l assembled concentrically therewith which is normally under compression urging the carriage 43 in the direction of the Yfixed portion 36. A link chain member 67 is secured at one end to the rear surface. of the carriage 43 and'extends in adirection away from the front of the machineV through the panel 35 having the other end coupled directlyuto a pistonrod 87 of a piston 88 travellinginV an air cylinder S9: vA sprocket wheel 68 Ais mounted on a shaft 92 and adapted for free rotation therein and positioned between the carriage 43 and the air-cylinder 89 and y .having teeth interlockingV with the link chain- 67 and adapted to translate linearmotion ofthe chain into rotary Y d motion. Similarly mounted on the shaft 92. and keyed thereto to prevent relative motion therebetween is a cam 93 which is parallel to the sprocket wheel. Riding against the surface of the cam is a cam follower 94 mounted on the end of an arm 95 directly attached to the shaft 96 of a motor regulator 97. This motor regulator may be of any of the well-known types such as a rheostat'or a variable reactor, iand is connected by electrical lines 9S and 99 to the motor 2l, whose output shaft lill is connected through the transmission 22 to the block ll.

. The operation of the invention will now be readily understood in the light of the discussion and with reference to the drawings. Y i

The tensioning control mechanism is then set so that the movable portion 37 is moved fully forward in the direction of the fixed portion 36, and this is accomplished by bleeding air from'the cylinder S9, thereby releasing to urge the frame 413 in a forwardly direction.

To initiate the wire drawing operation, the wire is coiled on the block .which is lst in the'linear series such as block ll with the leadend passed around the upper sheave s4 of the movable portion 37 and continuing on to the upper sheave 4l of the fixed portion 36 defining a loop. A second loop is accomplished by returning the lead to the lower lsheave l5 of the movable portion .and again to the fixed portion where a iinal turn is taken around the lower sheave ft2 'before the lead continues on to the die i7. It will be apparent that the tilting of the sheaves with respect to each other and with respect to the plane of the work surface will minimize the amount of scrubbing wise direction, as

or the tendency of the wire to bear against the rims of the sheaves. Consequently, it will be .seen that a relatively large loop of wire is used in the intertwining about the four sheaves which provides a large degree of flexibility and a-ner degree of stability in motor control. The wire is then-passed through'the die`17 to the next block in the linear series and a similar threading operation around its dancer control mechanism and through its corresponding die and subsequently through the remaining stages of the machine. Y f

All of the motors are startedth'rough a central control (not shown) to rotate the blocks at their respective speeds.

Simultaneously with the energizing of the motors, the operator introduces air from an independent source into the cylinder 89 through a conduit 91. The pressure of the air on the rod end of the piston 8S creates a tension on the chain 67acting to draw the movable carriage 43 away from the fixed portion 36. This action is counterbalanced by the wire'tension on the sheaves which tends to provide a floating action maintaining the movable portion Y37 in a state of equilibrium.

During the operation of the machine, it will be seen that as the wire leaves the block 1l and moves through the control means 29 yand through the die 17 to the block l2, the tension in the wire will produceforces that act on the xed portion 36 and the movable portion 37 tending to cause the movable portion to adjust itself yalong the rail 46 to a position located between itsmost forward position and `its most rearward position. An-increase in tension in positions about the shaft 96 ofthe regulator 97. This exerts a regulating action von the motor 2l to increase or decrease the speed'of rotation of theblock; If the Vwire tension decreases, this Vwould occurv because the block 1l is rotating too fast. The movable portion 37 will, therefore, move rearwardly away from` the xed lportion 36 and cause the sprocketwheel 65 to rotate slightly in a clockshown in FIG. 7. .The pam 93 being secured to the shaft 92 participates in this clockwise rotation and brings about a movement of the regulator arm 95 in such a manner as to slow down the motor 21. AS the speed of the motor 21 is reduced, the speed of the block 11 will also be reduced and tension in the wire on the dancer roll will increase and tend to return the movable portion 37 to its intermediate position. Naturally, of course, this type of control is not normally accomplished incrementally, as described above, but takes place by a so-called oating control wherein the movable portion tioats slightly causing the regulator 97 to float and maintain the motor 21 at a speed which will give the desired predetermined tension in the wire.

The guide 38 serves to hold the movable portion 37 in such a manner that it is restricted to movement in a horizontal plane parallel to the work surface 16. For example, movement of the links 5S and 56 about their pivotal axes cause their distal ends to move up and down vertically. The

links

55 and 56 must movel up and `down together since they are solidly locked together by the junction member 59, so that the pivotal axes 61 and 62 are always spaced the same distance apart. It can be seen from the geometry of the situation that the pivot pins 61 and 62 are always in the same vertical plane. They move up and down in this vertical plane which itself may move forwardly and rearwardly. It necessarily follows that since the pivot pins 61 and 62 always lie in the same vertical plane, the junction member 59 must remain in that same plane no matter how the

links

55 and 56 are moved. Since the junction 59 is secured to the other end of the

links

55 and 56 by pivot pins 61 and 62, movement of the links about the pivot pins 57 and 58 transmits motion in a corresponding vertical plane to the pivot pins 61 and 62.

It will be seen by referring to FIG. 2 that lateral motion of the carriage 43 is restricted to a straight line. This movement is transmitted to' the link members 63 and 644 by means of pivot pins 60 and 70 secured in the movable carriage 43. Consequently movement of the frame 43 will cause lateral motion of the ends of the

link members

63 and 64 and furthermore impart a lifting action to the junction member 59, allowing the

links

55 and 56 to pivot upwardly on the pins 57 and 58. Transverse movement of the carriage 43 is rigidly restricted by the action of the

rollers

47 and 48 on the carriage track 46. The weight of the carriage 43 is carried by the

rollers

47 and 48 on the rail 46 allowing a slight iioating action, but no attempt is made in this support method to restrict the movement of these members in a vertical plane, since in the atmosphere of wire drawing machines, there is a continuous accumulation of foreign matter such as dirt or metal particles associated with the drawing operation. It thus can `be seen that the movable portion 37 of the control means is arranged for lateral movement on the wire drawing machine without any danger of this motion being interrupted or changed by the conditions in the wire mill. The pivot pins associated with the guide 38 are enclosed and lubricated and are not subject to injury by mill conditions. At the same time, the movable portion 37 is restricted to the accurate to-and-fro motion which is necessary for accurate regulation of the block drive mechanism.

Furthermore, since the wire passes around four sheaves in passing from the block to the die, a considerable amount of wire in four large loops is involved and permits a more sensitive response of the block motors and a finer accuracy in regulating block speeds as small variations in tensions are multiplied through the mechanical advantage of the multiple sheaves. Consequently, the controller assures that the tension in the wirevwill not exceed a predetermined maximum and prevents `wire breakage particularly during the starting and stopping operation. Since the control means, particularly the movable portion,`moves forwardly sirable effect of a nonuctuating back-tension in the wire is well known. In addition, a safety factor is built into this type of machine as it is not necessary for the operator to lean far lout over the machine in threading it up or to climb onto the work surface, since by releasing the pneumatic pressure within the air cylinder of the regulator, the coil spring forces the movable portion forwardly in the direction of the iixed sheaves while threading is taking and rearwardly of the machine along a straight line, it is I not necessary to provide considerable spacing between the adjacent blocks to permit swinging movement of the control means, as would be true with theV pivotal arm-type dancer rolls heretofore known in the industry. The deplace. From the standpoint of relative ease in maintenance, it can be seen that the interior of the support 33 is readily accessible from the rear of the machine and that the motors and controls are easily maintained and adjusted utilizing this improved type of block speed regulation.

A modified form of the invention is shown in FIG. 8 compris-ing a different construction of the guide member. An intermediate member 54a is attached to the support 33a by a vertical hinge pin 53a in such a manner to allow pivotal movement in a horizontal plane. Extending transversely through the distal end of the intermediate member are a pair of vertically spaced pivot pins 57a and 58a having one end connected .to pairs of rocker -arms 55a and 56a. Disposed between the rocker arms is a bell crank member 59a connected to the rocker arms by pivot pins 61a and 62a laterally spaced from the pivot pins 57a and 58a. The bell crank member extends 4forwardly in a direction laway from the support 33a and has a pair of laterally spaced pins a and 66a extending transversely therethrough.` The carriage 43a has a pair of pins 60a and a transversely extending through the upper leg 76a providing a pivotal axis for a pair of link members 63a and `64a which -are directed angularly upward and have their opposite ends connected to the

pins

65a and 66a of the bell crank members. An `angularly extending coil springmember 51a is disposed between the transversely spaced

link members

63a and 64a having one end secured to the medial portion of the pin 66a and the other end secured to the frame.

The operation of this form of the invention is such that lateral movement of the carriage 43a in the direction of the support 33a in response to a decrease in tension on the wire which is compensated `for by movement of the carriage 43a in response to tension exerted through the chain 67a will exert Ian upward force on the

links

63a and 64a transmitting a lift-ing action through the bell crank member 59a` to the rocker arms 55a and 56a causing them to pivot upwardly about the pins 57a and 58a. Since the

link members

63a and 64a are iixed at one end t0 the carriage 43a, the amount of upward travel of the bell crank is restricted to a limit equivalent to the length of the

link members

63a and 64a. Consequently, when the link members are substantially normal to the plane of the leg 76a of the carriage 43a, the bell crank member 59a pivots downwardly about the pins 61a and 62a allowing the

link members

63a and 64a to reverse their angular d-irection relative to the bell crank.

The spring 51a is of the helical volute type and normally tensions the carriage 43a in the direction of the fixed sheaves 36. It will be seen, however, that as .the vertical distance between the bell crank 59a and the carriage 43a becomes greater, the spring tension will increase so that the spring will act to counterbalance the forces acting t0 exert upward pressure on the bell crank dening a iioating action and attempt to maintain the trarne 43a in a state of equilibrium or balance.

It is obvious that minor changes may be made in the for-m and construction of the invention without departing from the material spirit thereof. It is not, however, desired to confine the invention to the exact form herein shown .anddescribed, but it is desired to include all such as properly come within the scope claimed.

I claim:

1. A wire drawing machine including in combination a plurality of independently driven blocks longitudinally spaced from each other on a work surface, a plurality of dies positioned intermediate said driven blocks, and block speed controlling means dispose'dintermediate each Yof' said blocks, said controlling means comprising a fixed pair of sheaves in lateralV alignment with a laterally movable carriage, said movable lcarriage supporting a pair of sheaves angularly disposed to each other, wire passing between said blockshaving a plurality of loops passing around said fixed and movable sheaves, said carriage maintained in a state of equilibriumy along alateral line normal to a line passing through the center of said blocks by wire tensioning means opposed by fluid tensioning means, the movement of said carriage restricted to a horizontal plane and Acontrolled by tension on the wire passing around said sheaves whereby .linear positioning Vof said' carriage will actuate block speed regulators.

2. A wire drawing machine comprising in combination a plurality of independently driven rotatable blocks; a plurality of dies positioned intermediate said driven blocks, sheave members supported on a movable carriage disposed intermediate each of said blocks, means urging the carriage in one direction compensated by Huid tensioning means urging the carriage in the other direction, a bracket attached to said machine in superposed relation to said carriage, substantially horizontal link members having one end in vertical pivotal engagement with said bracket and a bell crank arm pivotally connected to the other end of said links, lever members extending angularly upward Vfrom said carriage andpivo-tably engaging said bell crank arm, whereby lateral movement of said carriage transmits vertical movement through said lbell crank to theV horizontal link members and restricts relative transverse motion therewith, wire passing between said rolls having,

loops engaging said sheaves, said carriage adaptedto shift laterally to tensions exerted on said sheave members by said loops, and block speed controlling means actuated through linear positioning of said carriage.

3. A Wire drawing Lmachine comprising in combination a plurality of independently drivenrrotatable blocks, a

plurality of dies positioned intermediate-said driven blocks, t-Wo pairs of rotatable sheave members disposed intermediate each of said blocks, one pair of sheaves xed and the other pair mounted on a movable carriage, wire passing between said blocks having loops engaging said sheaves and acting as means urging the carriage in one direction, lluid tensioning means urging the carriage in the other direction, means restricting the movement of said carriage to a straight line in a horizontal plane, said carriage adapted to shift in response to Varying tensions exerted on ysaid sheave members by said loops, 4block speed controlling means actuated in relation to the linear positioning of said carriagefsaid Yblock speed `controlling means comprising said fluid tensioning means which includes a hydraulic cylinder with a piston movable therein, said piston attached to said carriageby an elongated flexible element, which element cooperates with a rotatable ele- -ment disposed intermediate thecarriage and the cylinder forconverting linear motion of said elongated element to rotative motion of said rotatable element, means associated with said rotatable element in operative connection with a`block speed controller, whereby the block rotational speed will be varied as the said carriage is moved in response to changing loop tensions exerted thereon. f

References Cited by the Examiner UNITED STATES PATENTS 1,377,206- `5*/21 Lauren 20S- 14v 2,192,785 3/40` Bonds 205-14 2,205,213 6/40 Lessmann Y 20S- 14 2,242,435 5./41 Parvin et al. e; 205-14 2,321,612 6/'43 VNye 205-14 2,502,005 3/50 Hansell 205 14 CHARLES w. LANHAM, Primary Examiner. WILLIAM w. DYER, JR., Examiner.

Claims

1. A WIRE DRAWING MACHINE INCLUDING IN COMBINATION A PLURALITY OF INDEPENDENTLY DRIVEN BLOCKS LONGITUDINALLY SPACED FROM EACH OTHER ON A WORK SURFACE, A PLURALITY OF DIES POSITIONED INTERMEDIATE SAID DRIVEN BLOCKS, AND BLOCK SPEED CONTROLLING MEANS DISPOSED INTERMEDIATE EACH OF A SAID BLOCKS, SAID CONTROLLING MEANS COMPRISING A FIXED PAIR OF SHEAVES IN LATERAL ALIGNMENT WITH A LATERALLY MOVABLE CARRIAGE, SAID MOVEABLE CARRIAGE SUPPORTING A PAIR OF SHEAVES ANGULARLY DISPOSED TO EACH OTHER WIRE PASSING BETWEEN SAID BLOCKS HAVING A PLURALITY OF LOOPS PASSING AROUND SAID FIXED AND MOVABLE SHEAVES, SAID CARRIAGE MAINTAINED IN A STATE OF EQUILIBRIUM ALONG A LATERAL LINE NORMAL TO A LINE PASSING THROUGH THE CENTER OF SAID BLOCKS BY WIRE TENSIONING MEANS OPPOSED BY FLUID TENSIONING MEANS, THE MOVEMENT OF SAID CARRIAGE RESTRICTED TO A HORIZONTAL PLANE AND CONTROLLED BY TENSION ON THE WIRE PASSING AROUND SAID SHEAVES WHEREBY LINEAR POSITIONING OF SAID CARRIAGE WILL ACTUATE BLOCK SPEED REGULATORS.