US2659540A

US2659540A - Conduit reaming machine

Info

Publication number: US2659540A
Application number: US121844A
Authority: US
Inventors: Harry J Sketchley
Original assignee: Individual
Current assignee: Individual
Priority date: 1949-10-17
Filing date: 1949-10-17
Publication date: 1953-11-17
Anticipated expiration: 1970-11-17

Description

6 Sheets-Sheet l IN VEN TOR.

HUEBNER, BE E HL E R, WORRE L r HARRY J. SKETCHLE'K HERZ/G 8 CALDWELL,

ATTORNEYS.

Nov. 17, 1953 H. .1. SKETCHLEY CONDUIT REAMING'MACHINE Filed Oct, 17, 1949 NOV. 17, 1953 SKETCHLEY 2,659,540

CONDUIT REAMING MACHINE By W Nov. 17, 1953 SKETCHLEY 2,659,540

CONDUIT REAMING MACHINE Filed Oct. 17, 1949 6 Sheets-Sheet s SQ A 9 4 E R m .w "W a I TE P9 T N m v x E w J M .m & I ww W i W R 52 W A Wm. H w w A 0| fi. J

Nov. 17, 1953 H. J. SKETCHLEY 2,659,540

CONDUIT REAMING MACHINE Filed Oct. 17, 1949 6 Sheets-Sheet 4 HARRY J. SKETCHLEY,

INVENTOR.

HUEBNER, BE E HL E R, WORRE L HEIPZ/G 8 CALDWELL,

ATTORNEYS.

By 23. gm

Nov. 17, 1953 H. J. SKETCHLEY CONDUIT REAMING MACHINE 6 Sheets-Sheet 5 Filed Oct. 17. 1949 Patented Nov. 17, 1953 UNITED STATE 5 PATENT OF F ICE 2,659,540 CONDUi-T G MACHINE Harry-J. Sketchley, Los Angeles; Califi Application ct0ber17, 1949, Serial No; 121,844 I'Cla'iin'. (01. 242- 5 4) The invention relatesto conduitreamingi Inachines and'in particular a type' of machine frequently used in' cleaning sewer pipes andother pipes where an accumulation of residue on the Walls of the pipes over aperiod of timeimpedes the flow of water therethrough, such flow being purely a gravity flow unaccompanied by any pressure uponthe water. The application is-a continuation in part of application Serial No. 647,794; now Patent No.- 2,e88,039,-for a Wire Feeding and Retracting Apparatus directed'to a similar purpose.

The common practice in cleaning sewers and similar pipes is to attach a scraper or cleaner at the end of a flexible cable of some commercially acceptable manufacture and to push'a'nd force the scraper through'the pipe while at the same time rotating it',-th is being accomplished solely by means of forc'iblypaying out-the cable while simultaneously rotating it".

Heretofore a variety of machines havebeen devised suited to this general purposeandfor the most part theyhav'e'in'cluded' a frame; usually portable, uponwhichis'mounteda" separate carriage in turn'supphrtirig a reel for the cable and i pay-out rollers designed toguide'and extend the cable when thescraperisextended into the pipe. To rotate theca'blefa t" the same time that it is being payed out"it"has"beeri customary'to mount the carriage ro'tatablyupoh the fr'a'meso that the carriage, the reel and preferably the pay-out rollers all rotate'a'saunit. v

In a pipe cleaningoperatiohthe scraper frequently encounters obstructions which impede its extension into the pipean'dalso which restricts its rotation. When such obstructions are" en countered it becomes necessary to work' the scraper in and outuntil the'obstruction' ha's been removed sufliciently 'to perm'it thescraper to pass. Such operations entail'cbnsiderablemanipulation on the part of the operatcranda' repeated reversing of the p'ay-out'mechahismin order to work the scraperifi'ah'd out to cl 'earth'e'obstacle; Usually a relatively Iar'ge reelmu'stbe used in order to carry sufiicient came to'iext'en'd through the pipe" from one" manhole or sir'rlilar" junction to another and topar'ry' on 'a reel of large'cdiain; eter a sOmeWhatstifi cabIewhich will'not wind on a reel of small diameter. Theca'rria'ge fora reel of such size must be of e1ative1y1arg eproportions. This m'eans'alsothat for a given sp'eed of rotation'of 'the-reelthe rate of travel of 'the cable will vary'considerably, being relatively rapid when there are a' large numberiofcoilsof cable built up on the reelar'id relatively slow when the 2. reel is almost empty. Isthererore-becomes-eesira'ble to provide appropriate" means for cornpensa'ting for thes'peed changewhich the cable undergoes.

Also whenthe pay out'rollers' are working'so as-either to pay outcable'or to guide the passage of cable during a rewinding operation; because the rate of'travel of the cable onthe reel tends to'dififer from thespeedof operation'o'f the rollers there is constant likelihood-oi forming a in the cable betwe'en'these two points which may result in" damage to; the cable and the scraper and'increase the difiiculty of successfully operatingthe cable through'a longpipe. Because of the cumbersome nature of the apparatus where manual control for the application of power is relied upon'entirely' for working the cable and out, it happens that'n'iaiiy times the control is not properly exercised with'theresult' that the machinery is likely to be damagedand'tlie cleaning operation notpro'p'eriy accomplished;

In a further respect'difii'ciilty has been e'ricountered in the pay-out rolls 'of machineshereto'ioi-e contrived especially wheii'thecable becomes worn and often when the cable is pulled out of "a" pipe coated with'slime' and actuniulation of sand and gravel. Pay-out rollsheretofore utilized 'forforc ing" the cableir'itdthe'pipe havebeen found'fto lose efilcie'ncy and g'fiDDiri "power as the" cable be'oomesworn' and also when anything other thah a clearica'ble is run through thepay oiitrolla It isthrerore'amon'g the" objects of "the invention to provide a new and improved conduit reaming machine mcsrporat rigce'rtain automatic fatures capableof maintainih'g'a steady 'pull on all parts of the cable especiallywheri theoperation is reversed while at the same-time making provision for the necessary'apparatiis to sirnultane-v ously force the cable and the scraper thereon into the pipe while at the same time rotating: it;

Another object of the invention-is" toprov'i de a new and improved speed compensatmgmecha nis m for a? conduit reainifigimabhme which will compensate -for"di'fferences in speed at' whichfthe cable travels through the d-iiferent portions o'f the machine" and which is's'o coristructedthat'the compensation will be constantly applicablera gardless of changes the differential spee'das the-operation progresses Still another obj ect of the invention is 'to ipro vide a new and 7 improved conduit reaming ina chine equipped with an I automatically operative clutch to theendthatcthe storage reelfo r }the ta 11 b d w nfict d 1vwi P st,. @5 forcibly 'drive the cable into the pipe and whi'ch 3 automatically disengages the pay-out rolls and connects the reel to the source of power whenever the operation is reversed.

Still further among the objects of the invention is to provide an automatic drag on the reel which becomes operable while the reel rotates to deliver the cable to the pay-out roll and which becomes automatically inoperable when the reel is rotated to wind up the cable as it is withdrawn from the pipe.

Still another object is to provide in a conduit reaming machine pay-out rolls which are so constructed with respect to their cable-engaging perimeters that constant grip is had upon the cable at all times, the pay-out rolls being capable of automatically compensating for a reduction in size of the cable as wear increases and also capable of compensating for and accommodating an apparent temporary oversize in the cable as gravel and sand may be carried by the cable through the pay-out rolls.

The objects also include the provision of a conduit reaming machine all parts of which are adapted automatically to adjust themselves with respect to each other and thereby provide a smooth working machine, steady and eflicient in its operation, easy to manipulate during a pipe cleaning operation and at the same time sufficlently simple with respect to conventional mechanisms embodied in it so that the machine can be constructed of commercially available materials readily replaceable if necessary.

With these and other objects in view, the invention consists in the construction, arrangement and combination of the various parts of the device whereby the objects contemplated are attained, as hereinafter set forth, pointed out in the appended claims and illustrated in the accompanying drawings.

In the drawings:

Figure 1 is a side elevational view of the conduit ream-ing meachine with some structural parts in section and showing the relative locations of the storage reel and the pay-out roller assembly.

Figure 2 is a plan view of the machine shown in Figure 1.

Figure 3 is a diagrammatic representation of the portions comprising the drive which are located in the stationary part of the conduit reaming machine and which shows by dot and dash lines the transfer of the power to a rotating carriage.

Figure 4 is a fragmentary plan view, slightly enlarged and. partially in section taken on the line 4-4 of Figure 1 showing the automatic clutch and brake.

Figure 4A is a longitudinal sectional view of the differential mechanism.

Figure 5 is a horizontal sectional view of a portion of Figure 4 drawn to a still larger scale showing details of a ratchet drive.

Figure 6 is a fragmentary elevational sectional view taken on the line 66 of Figure 5.

Figure 7 is a transverse elevational view taken on the line l-'! of Figure 4 showing details of the drag.

Figure 8 is a transverse fragmentary sectional view taken on the line 8-8 of Figure 4.

Figure 9 is a perspective viewof a bearing box adapted to support the movable pay-out rolls.

Figure 10 is an elevational view partially in section taken on the line |0l 0 of Figure 2 showing a sprocket for rotating the rotatable carriage.

Figure 11 is a side elevational view partially 4 in section showing the pay-out roller assembly.

Figure 12 is a transverse sectional view taken on the line l2-l2 of Figure 11.

Figure 13 is a transverse sectional view taken on the line |3l3 of Figure 11.

Figure 14 is a fragmentary sectional view showing the construction of the cable-contacting portions of the pay-out rolls. v

Figure 15 is an exploded view in perspective of spring supporting parts of the pay-out roller assembly with springs and rollers removed for the sake of clarity.

An understanding of the general purpose of the device can best be achieved from an examination of Figures 1 and 2. As there shown there is a stationary frame It! designed to be carried by some portable vehicle, not shown, upon which is mounted a carriage ll encompassed within a rectangle of structural members which is designed to rotate upon the frame upon which it is supported by bearings l2 and I3. On the carriage II is a reel [4 which rotates upon a horizontal transverse axle [5 carried by the sides of the rectangular carriage H. The reel serves as a storage reel for a flexible cable 16.

At the right end of the carriage as viewed in Figures 1 and 2 is a pay-out roller assembly ll which includes three sets of pay-out rollers partly visible in Figure 2 over which the cable I5 is extended through the bearing I3 and thence upwardly at the right of the machine as viewed in Figures 1 and 2.

At the lower left-hand end of the machine as viewed in Figure 1 is a drive shaft 18 which derives its driving force from some conventional source of power at or adjacent the vehicle, the power in turn being utilized for two distinct purposes, one for rotation of the carriage II, and the other for rotation jointly of the storage reel and pay-out rollers, depending upon whether the cable is being payed out or withdrawn for rewinding upon the storage reel.

Inasmuch as the application of power to the storage reel and pay-out rollers must be upon the carriage II which is constantly rotating during operation, the power is transferred through one set of shafts, counter-shafts, transmission, and clutch located in a stationary portion of the frame and depicted diagrammatically in Figure 3. The power, however, must be transferred to a rotating gear train in the carriage II and therefore enters upon the carriage H by transmission through appropriate means in the bearing I3. In general when the device is being operated the pay-out rollers in the pay-out roller assembly I! are forcibly driven so as to draw the cable Hi from the storage reel and extend it forcibly into the pipe which is to be cleaned. During this phase of the operation the storage reel is unconnected to the source of power but is provided with a drag which prevents the reel from running too fast and which maintains a drag at all times upon the cable 16 so that it remains taut between the storage reel and the pay-out roller assembly.

When the apparatus is reversed for any reason the storage reel is then directly connected to the source of power and positively driven thereby while at the same time the drag is released. During this portion of the operation the application of power to the pay-out roller assembly is cut off but the pay-out rollers themselves provide a certain drag upon the cable; and by reason or a specially adapted difierential connection, which will be described in detail and hi is illustrated. in. part. in Figur :.v t e. sp ed. fv t tion of the-pay-out rollers willialways beadjusted with respect to the, speed of the cable as the speed changes with an. accumulation of coils of cablev upon the storage reelj.

The stationary drive The. location of the parts of the stationary drive-is found in Figures 1 and 2 and anunderstanding of the transfer of. power through this dr-ivewill best be appreciated. from the diagrammatic representation of Figure 3. AS indicated inlthedower left-hand portion of Figure 1 a drive shaft [8; introduces power to the system which supplies the conduit. reaming machine. The. drive shaft l 8 is joined through aclutch 2.0 toan. intermediate shaft 1.8.. A transmission 22 of conventional: design acceptspower from the intermediate shaft LB and transmits it to a sprocket 23, from which a chain drive, 24 transmits the power; to. a larger sprocket 25 which is in turn attached to the rotating carriage II. A clutch lever 2;! may be employed to connect and disconnect thetransmission 22. from its engagement with. the, intermediate shaft l8 thuscausing the carriage l I to rotate or cease rotationas desired. Details of the. mounting of the large sprocket 2.5, are best illustrated in Figure 10. As there shown-the sprocket 25lying adjacent the bearing 1.3,isbo1tedto, a channel 26 forming the adjacent endof thecar-riage l l and'both the sprocket and the channel have clamped between them a flange of a bearing shaft 21, this shaft being one extended through the, bearing [3 which in turn is. carried by-the, stationary frame, it.

For convenience a brake of conventional constructionidentified. by the reference character it and suitably controlled may be employed to retard rotation of the carriage l I.

Thepowerfrom the drive. shaftlB and clutch 20 is also conducted through the stationary portion of the rframe to the right-handend as viewed inFigures l, 2 and 3 for eventualv transmission tothe-parts carried by the rotating frame H. Power carriedin this direction is transferred first froma sprocket 30through a chaintl to a larger sprocket 32 which in turnis carried by a shaft 33; stationarily'supported in partupon a channel 34.0f the frame- H). A sprocket 35. at the righthand. end of the shaft drives av chain 35 and sprocket 31 which in turn sends the rotating source of power through a transmission 38. The transmission38-drives a shaft Isa-supported upon bearings 40 and 4| on adjacent portions of the stationary frame I0; From the shaft, 3,9.power mayrfollow one of two, courses to a shaft 42. For-payout or forward operation of the apparatus a clutch 43" may be appropriately] engaged by means of a. reversing clutch lever 44: to drivea sprocket 45. which through; a chain 4S and sprocket 41 rotates the shaft 4=2 ina corresponding direction. In reverseoperation manipulation oftheclutchlever 44'disengages the clutch 43* and engages'a clutch 48'so that power is transferred through a sprocket and chain 50 to a sprocketz 5k and reversing gears 52,1thereby' to rotatethe shaft: 42;in an opposite direction. The

clutch lever 44 may also bemanipulated to anintermediate neutral'position wherein no power is transmitted to the shaft 42. In either event rotationof-the shaft 42; is transferred by means ofrasprocket -53and'a:chain 54 to a sprocket 55 which. is; connectedto: a; hollow; sleeve shaft; 55

passing inside of the bearing I3 and also within 'tive pay-out roller shaftitt.

a hollow bearing shaft 51 and thence to asprocket 58 within the rotating, carriage.

The movable drive All portions of, the, drive beyond the sprocket 58 are mounted upon the carriage l-l androtate with the carriage asthetcarriage is: rotatedfor the purpose of rotating the cable. The necessity for this arrangement accounts for the transmission of power from. they sprocket 5,5through; the sleeve shaft 56 at a location such that the slee ie shaft 5% is concentric with the bearing shaft 57 comprising one of the bearings about which the carriage rotates.

From the sprocket 5d a chain 59 carries. power to a sprocket 58 mounted upon a counter-drive shaft 65 which isrotatably attached tothecarriage H by means of bearings 52.. The; relative location of the counter-drive shaftv 6| is best shown in the full lines'of Figurell and thedotted lines of Figure 1.

Turning now to Figure 4 it will be noted that the counterdrive shaft 6! extends beyond the adjacent bearing t2 where it supports a sprocket 53 from which a chain 6,4 transmits power to a sprocket 65 mounted upon and secured to a1 differential housing 66. By operation of, a differential device Within

thehousing

6,6; assisted-by a reversing clutch t l, the parts and operation of which will be later described in detail, power, is transmitted to a driven counter-shaftfiafor; the purpose of driving the pay-out rollers. In; another position of adjustment: of the; clutch, power is transmitted through a stub shaft69- and thence to a reel driving shaft ill. Theshaft IQ; journalled in bearings H and. 72. on the carriage, transmits power through a, pair of spur gears-13 to a shaft is which, through a sprocket; 7.5;,a chain is, and a sprocket 17, rotates the storage reel 14 when the wheel is; operate d;to=;wind up cable.

The pay-out roller cage assembly The driven counter-shaft GB -issupported upon bearings 83, BI and 32 on the carriage H. A set of bevel gears 83 keyed to the-driven countershaft fitrnesh with corresponding bevel gears 84 as shown in Figures 1i and 2; the bevel gears -84 being carriedby pay-out roller shafts-85; as perhaps best shown in Figure 12'. The pay-out roller shafts 85 in each case are supported inbearing boxes 88' and these in turn areslidablyreceived in slots 8? which extendupwardlyinto plate-like side members 88 of the-payout.rollercage. IFhe blocks are held upwardly by means ofstrips-BH which may be anchored in place by bolts 9%. Mounted in this manner the bearing boxeshave a limited downward movement but are provided with a certainfreedomto Inove'upwardly under certain circumstances.

Midway between oppositely disposed bearing boxes 86' there is mounted on eaclrof the-pay+out roller shafts 85" apay-out-roller 9i boltedto'a bushing 92 whichis in turnkeyed to. then-espec- The 1 circumference of the pay-out roller is. adapted toengage the cable It. a

As is best portrayedin Figure 12- the-righthand ends of the payroutlroller shafts'teiias there shown have keyed thereto in each case a gear at which meshes witha corresponding gear 84 of the same. diameter and number of teeth, the gear-34 being keyed; to a corresponding shaft: 95,: the

. shafts=95zbeing equal iinnumberandicomprisingia set of pay-out roller shafts located on the op- 7 posite side of the cable I6 from the pay-out roller shafts 9 I.

The shafts 95 are also supported in bearing boxes 96 illustrated in greater detail in Figure 9 but illustrated best as to location on the roller cage in Figure 12. Midway between the bearing boxes 96 on each shaft 95 is located a pay-out roller 91 which is complementary to the pay-out roller 9I and the perimeter of which also engages the cable It. The pay-out roller 91 is bolted to a bushing 98 which is keyed to the shaft 95 in each In order that the cable I6 may be successfully manipulated between the pay-out rollers in a manner which will compensate for wear and will also assure continuity of grip upon the cable when it becomes covered with slime in which sand and gravel has become embedded, pressure is placed upon the pay-out rollers 91 in order to push them against their opposite pay-out rollers 9|. The pressure is exerted by a set of springs which are designed to exert their influence upon the bearing boxes 95 and thus urge the shafts 95 carrying the pay-out rollers 9'! downwardly as viewed in Figures 11 and 12. The spring retention mechanism is best shown in Figure 15;

Referring once again to the bearing boxes as illustrated in Figure 9, it will be noted that these bearing boxes are provided with slideways I on each side which are adapted to slide along vertical edges IOI which form the sides of slots I02 extending downwardly from the upper of the plate-like side members 80. The bearing boxes are provided with apertures I93 designed for the reception of a pilot I04 at the lower end of a push plate I05. The push plate in turn includes a guide plate I06 carrying springneepers I01 and is also provided with slideways I 33 which are adapted to slide along the edges its of the slots I02. I

To provide the necessary support for compression springs spring bed plates I09 are securely mounted between the side members 88 by means of pins H0. These spring bed plates have recesses III at the sides for the accommodation of springs I20. At the centers of the bed plates are bolts I I2 anchored thereto and which extend upwardly through apertures H3 in spring cap plates H4. By means of a nut H5 and lock nut H6 the spring cap plates H4 may be anchored in a position higher or lower with respect to the bed plates I09 as occasion demands. The cap plates H4 are also provided with slideways Hl, these slideways also being designed to slide up and down along the edges IOI of the slots I02. The cap plates, however, include extensions H8 which project outwardly upon the side members 88 so that the heavy compression springs I20 may engage beneath the extensions H8 at the upper ends and may press against the guide plates I05 at the lower ends where they are retained in proper position by the springkeepers I01.

It will be self-evident that when pressure is built up in the springs I20 they press downwardly upon the guide plates I06, the push plates I05 and thence through the pilot I04 and press downwardly upon the shaft 95 in the bearing boxes 96. Pressure thus exerted presses the pay-out rollers 91 smoothly and evenly against the cable.

If for any reason it should be necessary to adjust or change the spring tension, it is necessary ing upon the change in spring tension desired.

Pay-out roller design The pay-out rollers are specially constructed for the purpose of assuring a firm grip upon the cable I6 at all times. Details of the construction are illustrated in Figure 14. An inspection of the configuration of the pay-out rollers 9| and 91 there shown will reveal the utilization of complementary grooves H9 and H9. It will be noted in comparing the radii of the grooves with the radius of the cable I6 that the radii of curvature of the grooves may be slightly less than the radius of the cable I6. It is also important to note that on the right side as viewed in Figure I4 the pay-out roller has a perimeter I2I having a slightly greater radius than a perimeter I22 on the opposite side of the pay-out roller. On the pay-out roller 91 the relationship is reversed so that a perimeter I2I which is opposite the perimeter I22 is greater in circumference than the oppositely disposed perimeter I22 and a perimeter I22 is less than the perimeter I2I. The perimeters referred to are thus complementarily disposed with the axes of the respective shafts being so located that the perimeters do not touch. Hence pressure will be exerted by the grooves H9 and I I9 upon the cable with the pressure being greatest at the edges of the grooves.

At the bottoms of the grooves H9 and I I9, respectively, there are provided auxiliary annular grooves I23 substantially smaller in cross-sectional area but defining edges at the junction of the groove I23 with the groove H9 for example.

By providing a relationship of the type described a firm grip can be had upon the cable It. Should the cable begin to wear, the cable will do no more than set deeper in the grooves and the pressure of springs I20 will be exerted upon the bearing boxes 98, thus tending perpetually to move the shafts 95 and corresponding payout rollers 91 toward the pay-out rollers 9I. Acting in this way there is always the pressure of the pay-out rollers upon the cable. The pressure, however, is a releasable pressure to the end that should a dirty cable carry upon it small particles of gravel or sand, the pay-out roller 91 may be forced upwardly against spring pressure in order to permit the gravel or sand to pass without excessive pressure being apt to damage the cable. Pressure of the same springs I20 likewise tends to maintain a frictional grip between the pay-out rollers and the cable as the diameter of the cable grows smaller after being subjected to wear.

The automatic clutch In order for the device to operate in the manner necessary to achieve its objects it is necessary that when the pay-out rolls are being driven so as to feed the cable I 6 outwardly into a pipe, the storage reel should be disconnected from the drive. Running freely, however, the storage reel would not pay out the cable properly so that a braking device or drag need be employed. An automatic drag I25 serves this purpose, details of which are best illustrated in Figure '7 and the location of which is best shown in Figure 2. Furthermore, when it is desired to retract the cable, it is necessary to disconnect the power from its driving relationship with the pay-out rolls and to connect the power so that the storage reel is driven in a wind-up or reel-in direction. To dispense with'the reliance upon manual control of this phase of operation of the machine there is provided an automatic clutch 61, detailed parts of which are shown in Figures 4, and 8. The location of the automatic clutch 61 is also clearly illustrated in Figure 2.

During a pay-out operation when the cable is being fed into a pipe, the counter-drive shaft GI is being rotated in the direction of the arrow illustrated in Figures 4 and 5. To operate the automatic clutch there is provided a separate threaded end comprising a screw element I26. The screw element is mounted in a special bushing 421, shown also in Figure 6, and includes a space I25 within which a ratchet wheel I29 is adapted to rotate. The ratchet wheel is fastened non-rotatably to the counter-drive shaft 6| by means of a set screw I30, the bushing being retained in position by application of a plate I3! over one side of the ratchet wheel, as illustrated in Figure 5.

Teeth I32 on the ratchet wheel are adapted to cooperate with a detent I33 spring pressed into position by a coil spring I34 acting against a piston I35. A spring housing I36 is adapted to contain the spring which is held in position by a nut I31. The spring tension is maintained relatively light so that when the rotation in either direction of the bushing I2? is arrested, the ratchet wheel may continue to rotate with the teeth I32 passing successively beneath the detent I33.

When the apparatus is being driven in a forward or pay-out direction and the driven countershaft SI is rotating in the direction of the arrow, as illustrated in Figure 5, action of the screw 25 in a reversing block I38 tends to shift the reversing block from right to left as viewed in Figure 5 until the block strikes against a stop I39. While the reversing block is being shifted by rotation of the screw, the detent I33 temporarily engages one of the teeth I32 so that the screw I26 and bushing I21 rotate simultaneously with the driven counter-shaft SI, the reversing block in turn being held non-rotatably by an automatic clutch lever I49 in turn connected to the reversing clutch. As soon as the reversing block I33 strikes the stop I39, rotation of the screw is arrested and thereafter as the counterdrive shaft GI continues to rotate the teeth I32 will continue to pass beneath the detent.

The automatic clutch lever I40, being pivotally anchored by a bolt I4! to a bracket I 42, pivots about the bolt. Therefore Whenthe reversing block I38 is shifted from right to left, as viewed in Figure 4 for example, the lever shifts a clutch block I43 from left to right. The clutch block is provided with a serrated clutch base I44 with teeth facing in a direction such that they are adapted to engage corresponding teeth in a serrated clutch face I45 forming part of the housing 66. In this connection it should be noted that the clutch block is keyed to the stub shaft 69 and rotates with the shaft, an annular groove I45 being provided to slidably accommodate pins I41 of the automatic clutch lever I40. In this position of adjustment the stub shaft 69 is caused to rotate simultaneously with the housing 66 by reason of engagement of the clutch faces wherein the clutch block I43 is driven by rotation of the housing.

As an aid in understanding the operation of the differential housing 66 attention is directed to Figure 4A which illustrates the interior arrangement of the housing. As there shown the housing 66 is provided with idling miter gears I50 freely rotating on stub shafts I5I secured to the inside circumference of the housing 66.

Meshing with the idling miter gears on one side is a larger miter gear I52 which in turn is keyed to the driven counter-shaft 68. A second larger miter gear I53 is keyed to the stub shaft 69. It will thus become apparent that when the clutch faces anchor the clutch block I43 to the housing, the stub shaft 69 will be forced to rotate with the housing. This anchored relationship in turn restricts rotation of the idling miter gears and consequently rotation of the larger miter gear I52 will. be restricted relatively to the stub shaft 69 and as a result rotation of the housing will be transferred to the counter-driven'shaft 68 which will continue rotation at the same rate of speed as the housing 66 and in the same direction. This is the direction shown by the arrow inFigures 4A and ll and is the direction of rotation necessary to rotate the pay-out rollers in a pay-rout direction.

When the operation of the device is to be reversed so as to withdraw the cable from its extended position in the pipe, operation of the drive is reversed by shifting the clutch lever 44 to an opposite position so that the clutch 48 engages theshaft 49 and the clutch 43 is released from engagement. In this position of adjustment ro tation of the shaft 39 is transmitted to the reversing gears 52 causing the shaft 42 to operate in a reverse direction of rotation and this reversal is in turn transmitted through the chains and sprockets heretofore referred to to the driven counter-shaft BI. When rotation of the driven counter-shaft is reversed, the direction of rotation of the screw I26 is also reversed and this causes the screw to rotate in the reversing block I3! and draw the reversing block away from the stop I39, shifting it from left to right until it strikes the bushing I 21. During this operation the detent I 33 again comes into play engaging one of the teeth I32to cause the screw to rotate with the counter-drive shaft 6I until axial motion of the reversing block I38 is stopped,'at which point the ratchet wheel again continues to, rotate past the detent.

'As thereversing block I38 changes position, the clutch block I43 is shifted from right to left as shown in'l igure 4, which shift releases the clutch faces I44 and I45 from engagement and extends a serrated'clutch face I54 on the opposite side of the clutch block so that the'teeth engageteeth on the serrated face I55 'of a clutch block I56 keyed to the reel driving shaft '10. It will be noted from this description that a reversal in rotation from the pay-out adjustment automatically disengages the clutch block I 43 from the housing 66 and engages the clutch block with the reel driving shaft. In this position of adjustment rotation of the housing 66 in the opposite direction causes the idling miter gears I50 to rotate in a corresponding direction with the housing. Since the idling miter gears mesh with both the miter gears I52 and I53, the stub shaft 69 is rotated in a reverse direction as is also the driven counter-shaft 88. Consequently the payout rollers would be rotated in a reverse direction tending to draw in on the cable. The stub shaft 69, being rotated in a reverse direction, forces the reel driving shaft 10 to be rotated in a corresponding direction and thus power is applied to the storage reel so that the storage reel rotates in a direction pulling the cable inwardly and coiling it upon the circumference of the reel. The cable is carried upon the reel by transverse guide pins I51 and during the course of operat1on the coils upon the storage reel are prevented 11 from looping outwardly by pins I58 included for reasons of safety.

It will be appreciated that when the storage reel is substantially empty of cable as power is applied to the reel, the cable will be wound around the circumference of the wheel but that the circumference where the cable lies will be relatively small. As the cable begins to build up on the storage reel the circumference of the reel becomes relatively larger as the cable is rolled upon itself so that for a given rate of rotation of the storage reel the circumferential rate of travel is faster and the cable is withdrawn at a correspondingly faster rate. Because of a tight grip of the pay-out rollers upon the cable it becomes necessary to compensate for this change of speed in the rate of rotation of the pay-out rollers. This is accomplished by the interposition of the differential mechanism in the housing 66 which operates on much the same principle as the differential at the rear axle of an automobile. As the speed of withdrawal of the cable I6 tends to increase with the growing circumference of the storage reel, tension is built up in the length of cable between the reel and the nearest pay-out roll. This tension has a tendency to retar the rate of rotation of the storage reel which causes a retardation in the rate of rotation of the large miter gear I53. At the same time because of the fact that the large miter gear I52 is geared to the large miter gear I53, the rate of rotation of the driven counter-shaft 68 tends to increase to a point where the tension on the cable between the storage reel and the pay-out rollers is minimized. As the building up of the coils of cable on the storage reel continues, the rate of withdrawal of the cable constantly varies but this variation is continuously compensated for automatically by the differential mechanism in the manner described. Because of the fact that the grip of the pay-out rollers is maintained upon the cable while the storage reel is being operated, a tension will always be maintained on the length of cable between the storage reel and the pay-out rollers so that there will be no likelihood of the cable slackening or kicking during a reverse operation. This will be true even though the cable may be worked back and forth between pay-out and reel-in positions in order to work the scraper past an obstruction in the pipe. The compensating factors and the reversing operation by virtue of the automatic reversing clutch 61 will always take place automatically so that all of the moving parts will remain in proper operative adjustment.

The automatic drag To further assure a complete automatic adjustment of all of the parts the automatic drag I25 illustrated in Figure 7 connects and disconnects without the necessity of any manual adjustment. When the cable is being payed out and the reel is running free from the source of power, the reel driving shaft 10 will be rotating counter-clockwise in the direction of the arrows shown in Figure 7. Rotation of the reel driving shaft is transmitted to a brake drum I60 about which are retained an upper brake shoe I6I and a lower brake shoe I62 pivotally secured together by a pin I63. A brake shoe arm I64 connected to the brake shoe I62 includes adjustable screws I65 and I65, the adjustable screw I66 being adapted to engage a stop I 61 and the adjustable screw I65 being adapted, to engage one end of a lever I68 at a point such that the lever rotating about a pin I69 is shifted so that its end I10 presses downwardly upon the stop I61. The tendency of the brake shoe I62 to rotate will thus be sharply arrested and a slight friction between the brake shoe I62 and the brake drum I60 will be maintained sufficient to retard, without stopping, the rotation of the reel driving shaft 10 and thus exert a retarding efiect upon the rotation of the storage reel during a pay-out operation.

When the operation of the device is reversed, rotation of the reel driving shaft 10 is reversed and the reel driving shaft is then driven through the reversing clutch 61 clockwise as viewed in Figure '7. Operating in this direction such initial frictional force as may exist between the brake drum and either the brake shoe I52 or the brake shoe I6I tends to rotate the brake shoe arm I64 directly as well as tending to rotate downwardly a second brake shoe arm I1I attached to the brake shoe I6I. This tendency assisted by compression springs I12 and I13 tends to move the brake shoe arm I10 downwardly which tends to move the lever I58 downwardly pressing upon the adjusting screw I65 which in turn tends, through the brake shoe arm I64, to release the brake shoe I62 from frictional engagement with the brake drum I60. The same tendency of the brake shoe arm I64 to move downwardly is transmitted to the brake shoe I6I and its corresponding brake shoe arm I1I but this tendency is again transmitted and with added force to the adjusting screw I65, thus tending to increase the release of the brake shoe from the brake drum. It will be apparent that this action begins to and continues to take place automatically as promptly as the reel driving shaft is reversed. On the contrary, as the reel driving shaft is released from its driving relationship with the reversing clutch block upon a reversal of rotation of the stub shaft 10, the automatic brake or retarding device immediately becomes operative to exert a drag upon rotation of the reel driving shaft and thus maintain a tension upon the cable. Operation in either direction of the mechanism will automatically bring into play the brake mechanism causing it either to brake or release and also will cause the reversing clutch block automatically to take either one of two positions, namely, a position driving the pay-out rollers through a feeding movement or driving the reel through a rewind or take-up movement. The compensating effect of the differential becomes automatically operable upon release of the clutch faces I44 and I45.

In the mechanism thus described there has been provided the cable mechanism adapted to pay out cable to a length as great as can be accumulated on the storage reel while at the same time rotating the cable and assuring a smoothness of operation by elimination of all tendency to create slack which might result in kinks. By reason of the automatic features comprising an automatic reversing differential device and an automatic operable drag a tension is maintained on the cable in a reverse direction as well as in a pay-out or forward direction without it being necessary to release the grip of the pay-out rollers upon the cable. The means thus provided automatically releases the drag upon the reel when power is applied to it for reeling in the cable and effectively compensates for changes in speed of the different rotating parts without it being necessary to disengage any of them and without likelihood of damage to parts of the device which might otherwise result from excessive tension on the cable. All of the features described and particularly the automatic shift remain operable at all times while the carriage is being rotated in order to rotate the cable and work with equal efiectiveness whenever the carriage might be maintained stationary. Rotation of the carriage is separately controlled through an independent transmission and clutch. While I have herein shown and described my invention in what I have conceived to be the most practical and preferred embodiment, it is recognized that departures may be made therefrom within the scope of my invention, which is not to be limited to the details disclosed herein but is to be accorded the full scope of the claim so as to embrace any and all equivalent devices.

Having described my invention what I claim as new and desire to secure by Letters Patent is:

A reversible cable pay-out and rotating mechanism comprising a carriage, a pay-out roller cage on the carriage, oppositely disposed rollers therein having complementary cable gripping grooves and spring means between the cage and the grooves adapted to press said rollers into contact with the cable in all adjustments of the mechanism, a reversible source of power including a reversible drive shaft on the carriage, a combined clutch and differential device including a two- Way clutch and differential gearing subject to operation by the drive shaft, said drive shaft hav- 14 ing a permanent connection through the differential gearing to the pay-out rollers and an intermittent connection through the differential gearirr to the cable storage reel, an automatically operable friction drag on the cable storage reel having an operative position when the intermittent connection is broken and an inoperative position when the intermittent connection is made, and an automatically reversible clutch arm for the two-way clutch responsive to the direction of rotation of the reversible drive shaft having one position wherein the two-Way clutch makes said intermittent connection and another position wherein the two-way clutch breaks said intermittent connection and locks the differential gearing.

HARRY J. SKETCHLEY.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,904,885 Seeley Apr. 18, 1933 2,091,756 Fodor Aug. 31, 1937 2,137,776 Mitchell Feb. 21, 1939 2,223,005 Kerber Nov. 26, 1940 2,247,004 Sullivan June 24, 1941 2,251,291 Reichelt Aug. 5, 1941 2,339,762 Bruestle Jan. 25, 1944 2,392,226 Butterworth Jan. 1, 1946