US3713300A

US3713300A - Cable laying device

Info

Publication number: US3713300A
Application number: US00200458A
Authority: US
Inventors: G Ward
Original assignee: Individual
Current assignee: Individual
Priority date: 1971-11-19
Filing date: 1971-11-19
Publication date: 1973-01-30
Anticipated expiration: 1990-01-30
Also published as: GB1407237A; DE2256502A1; DE7242391U; DE2256502C3; DE2256502B2; CA953516A

Abstract

A cable layer unit comprising a tractive carrier with pairs of front and rear traction wheels, a digger blade which either meters or pulls a cable and disposed between the pairs of wheels, a drive for moving the blade in an elliptical path for slicing through the ground; a drive for raising and lowering the blade; and a pivot bar in front and rear of the unit upon which the unit is tilted to enter the blade into the ground close to a building and to raise the blade out of the ground close to a building.

Description

United States Patent Ward 1 1 Jan. 30, 1973 1541 CABLE LAYING DEVICE 2,530,230 1/1951 Boggs ..172/42 x 3,326,009 6/1967 Gagne ..6l/72.6 [76] memo" g 583 BOX 3,371,495 3/1968 Kaercher,.lr.. ..6l/72.7 P 0 3,508,616 4 1970 Hubbard ..172 40 [22] Filed: No 19, 1971 3,516,260 6 1970 Wood,.lr ..6l/72.6

[ PP 2001458 Primary ExaminerJacob Shapiro Related [1.8. Application Data AtmmeyRobert Heme [63] Continuation-in-part of Ser. No. 828,821, Sept. 17, [57] ABSTRACT A cable layer unit comprising a tractwe carrier with pairs of front and rear traction wheels, 21 digger blade [52] U.S.Cl. ..61/72.6,37/l93, 1177247402, which either meters or pulls a cable and disposed [51] Int Cl Aolb 3/64 Aolb 11/00 F16] 1/00 between the pairs of wheels, a drive for moving the [58] Fie'ld 6l/726 721 5 72 7, blade in an elliptical path for slicing through the 16 d 3 L ground; a drive for raising and lowering the blade; and a pivot bar in front and rear of the unit upon which the unit is tilted to enter the blade into the ground [56] References Clted close to a building and to raise the blade out of the UNITED S S PATENTS ground close to a building.

2,414,994 1/1947 wright ..61/72.6 X 17 Claims, 25 Drawing Figures PAIENTEMuao um SHEET '4 [1F 8 NEUTRAL PATENTEUJANBO I975 3.7 l 3, 300

sum

5 or 8 mull I I! III lli ll! IE IF IEAIII IMHiIHIIR IHIB IB IF II? WHIP PAIENIEnJAnaoma 3 713300 SHEET 7 [1F 8 CABLE LAYING DEVICE This application is a continuation in part of my application Ser. No. 828,82l filed Sept. 17, I969.

DISCUSSION OF THE PRIOR ART Cable layers of the prior art are unwieldy and difficult to maneuver. They normally cannot be started or finish close to a building, pole or obstruction which necessitates either manual digging or the use of other equipment. The action of the blade is either an up and down slicing action or horizontally back and forth impact action. Each of these have some limitations. The slicing (vibrating) action must be at a very fast speed particularly in hard ground causing excessive vibration that transmits through the machine causing not only fatigue failure, but exhausts the operator. The impact action has its limitations in some soils such as sandy loam. Both methods are limited in certain soil conditions and combining these actions into a continuous motion to obtain the optimum of both makes a versatile desirable machine.

In order to transport prior art machines the blade must be removed each time before transporting or manually moved or they are of awkward construction, inefficient, or the mechanism to get the blade to clear the ground is very costly.

The blade is usually positioned in prior art devices rearwardly of the drive wheels. Some are forwardly. Thus the traction of the unit is not concentrated on the drive wheels and full power of the unit cannot be utilized since the traction wheels tend to slip. Prior art machines must have additional wheels to balance, but are not driven and usually present awkward and cumbersome appearances and are limited in maneuverabili- SUMMARY OF THE INVENTION A general object of the invention is to provide a novel balanced and compact cable laying device which is facile to use with increased traction and flotation.

A different object is to provide a cable layer which comprises a bogie with a pair of front and a pair of rear traction drive wheels and a blade mounted medially between the wheels whereby draft of the load is transferred substantially equally to all of the wheels.

A further object is to provide in a cable layer means for tipping it in such a way that the blade can be set in and brought up close to a building or other structure.

Another object is to provide in a cable layer means for telescoping the blade up or down to adjust its depth or put it in transport position.

A still further object is to provide a novel drive for the blade which moves it in an elliptical orbit such that the blade slices and impacts into the ground and the point not only dips forwardly but also moves upwardly.

Another object is to combine slicing and impact actions of the blade to obtain a continuous uninterrupted and efficient digging action. A corrollary object in conjunction with the digging actions of the blade is to facilitate ejection of the cable from the blade.

Another object is to provide a novel cable layer having a crank-type blade drive intermediate its ends and a swinging link connection adjacent one end which causes the blade to move in an elliptical path.

A further object is to devise a novel cable laying machine which is balanced to facilitate tipping it for entering the blade into the ground and withdrawing the blade with equal ease and wherein the parts are arranged to obtain maximum traction.

A further object is to devise a novel dirt shield which functions not only to keep the dirt out of the working parts, but also serves to smooth down the turf through which the blade cuts.

Another object is to provide an improved blade structure which facilitates threading of the cable through the blade and removal of such cables.

A still further object is to provide a novel improved lock between the blade and the activating mechanism, the lock serving to hold the blade in assembly with the supporting guide linkage.

These and other objects and advantages inherent in and encompassed by the invention will become more apparent from the specification and drawings, wherein:

FIG. 1 is a side elevational view of my novel cable laying machine with the blade extended into the ground;

FIG. 2 is an enlarged cross-sectional view of the blade of FIG. 1 taken substantially on line 22;

FIG. 3 is an enlarged fragmentary side elevational view of the lower portion of the blade;

FIG. 4 is a fragmentary side elevation of the machine showing the machine tilted to withdraw the blade;

FIG. 5 is a fragmentary side elevational view showing the parts in position to enter the blade into the ground;

FIG. 6 is a fragmentary side elevational view of the unit showing the blade in transport position;

FIG. 7 is a rear elevational view of the machine;

FIG. 8 is an enlarged side elevational view of the blade and drive therefor;

FIG. 9 is an enlarged cross-sectional view taken essentially on line 99 of FIG. 8;

FIG. 10 is an enlarged vertical sectional view taken substantially on line 10 10 of FIG. 9;

FIG. I1 is a cross-sectional view taken substantially on line lIll of FIG. 10;

FIG. 12 is a rear view taken on line 12-12 of FIG. 8;

FIG. 13 is an enlarged cross-sectional view taken substantially on line 13-13 of FIG. 1;

FIG. 14 is a perspective view of the drive to the various components;

FIG. 15 is a side view of a different drive arrangement for the blade; and

FIG. 16 is a fragmentary view of my novel cable laying machine incorporating hydraulic tilting mechanism",

FIG. 17 is a fragmentary side elevational view of another embodiment of the invention partly in vertical section;

FIG. 18 is a fragmentary enlarged side elevational view of a modified form of blade partly in vertical section;

FIG. 19 is a fragmentary rear elevational view taken on line 19-19 of FIG. 18;

FIG. 20 is a side elevational view of the blade with the improved locking means therefor;

FIG. 21 is an enlarged fragmentary view of the upper portion of the locking rod;

FIG. 22 is a sectional view on line 22-22 of FIG. 21;

FIG. 23 is a fragmentary enlarged side elevational view of the locking device shown in association with the blade and crank block;

FIG. 24 is a sectional view taken substantially on line 24--24 of FIG. 17; and

FIG. 25 shows the parts in vertical section with the blade in position for removal from the shield.

EMBODIMENT OF FIGS. 1 14 Describing the invention in detail and having particular reference to FIGS. 1-14 of the drawings there is shown a cable laying machine generally designated 1 including a frame 2 in the form of a gear case which has a front and rear wheel and

axle assemblies

4 and 5 journalled in bearings in the side walls 7 and 8 thereof, the outer end portion of the

shafts

4 and 5 being connected to drive and

tractions wheels

9,9 and 10,10, respectively. The arrangement ofthe wheels give optimum traction and improved flotation.

The casing is a hollow container formed with a center vertical opening 12 defined by front and rear walls l3a,13b side walls 13,14 which are provided with

bearings

15,16, respectively, which are transversely aligned and mount journal stub-

shafts

17,18 having throws or

cranks

19,20 which are journalled in

bearings

21,22 mounted coaxially in

opposite side portions

23,24 of a mounting block which has a vertical slot 26 therein complementally admitting a vertically disposed digger blade 27. The block 25 is provided at opposite sides with

straps

28,29 which at their lower ends are bolted to upper ears at 23',24 (FIG. 12) on

respective side portions

23,24 and flank the blade 27.

The upper ends of the straps are pivoted to trunnions 30,31 (FIG. 9) of a friction or wedge collar 32 which has a pair of

side webs

33,34 and end

walls

35,35 which define a rectangular vertical aperture 38 admitting the blade 27 therethrough. The wall 36 is provided with an car 39 between the

side webs

33,34 in which there are hooked one of the ends of tension springs 41,42 which are hooked at the other ends to anchors shown as cotter keys 41 ',42' fastened to the upper ends of

straps

28,29 which are embraced by outer ends of a pair of

links

43,44. The collar is urged into frictional wedging engagement at diagonally opposite upper and lower preferably friction material-covered corners 45,46 (FIG. 10) with the front and rear edges 48,49 of the blade 27.

The swing links 43,44 are pivoted at their other ends on a pin which is connected to an anchor lug 51 formed on the casing. The links are interconnected by a spacer-bolt assembly 53 and function to control the movement of the blade with the crank assembly in an elliptical path designated 54 in FIG. 3.

A stop bolt 55 extends through any of a series of

openings

55',56,57,58 and rests on top of the collar and serves to limit the downward position of the blade for various selected depths and the bolt 55 also connects the flanges 57',58 of a U-shaped shield 60 to the blade. The shield 60 is shown in the top position and has its bight portion 61 shown engaged with the active end 62 of a pawl 63 preparatory to the blade being elevated.

The pawl 63 is U-shaped and in addition to having the cross-member active end portion 62 has a pair of legs 64,65 (FIG. 11) which flank a kidney shaped mounting structure 67 formed as part of the anchor lug 51. The

lugs

64,65 pivot at their free ends on a spring loaded cross-pin 68 which is movable axially transversely of the structure 67 and in addition to having a round section portion 70 on which the legs of the pawl pivot has a flat section 72 which interrupts the cylindrical section, and which is adapted to accommodate movement of the pawl with the pin in the arcuate slot 73 in the mounting structure, is adapted to be turned edgewise in alignment with the arc of the slot 73. The cylindrical portion attendant to pulling the pin by handle 74 endwise withdraws the cylindrical portion from the

respective notches

75,76,77 in which the pin is located to condition the pawl to up, neutral" and down positions. A pin 78 is mounted intermediate the ends of

legs

64,65 and about which one end of the biasing compression spring 79 is hooked which at its other end is seated on the edge 80 of the mounting structure and positioned intermediate the top and bottom ends of the edge 80 on the boss 80. Thus in the down position the spring is angled down; in neutral it is aligned with the pawl which has its active end clearing the blade edge, and in the down position the spring is angled upwardly. The spring thus has a center neutral position and overcenter positions above and below neutral.

In order to raise the blades the pawl is set as shown in FIG. 10 with the active end 62 seating on the shield portion 61. The spacing between the area of engagement of portion 62 with 61 is preferably slightly less than the upward length of the stroke of the crank drive so that in one turn of the crank the blade will rise sufficiently to enter portion 62 in the upper most notch 82. The blade slides up one increment through the locking collar and the pawl prevents descent of the blade on the downstroke portion of the crank. The action continues step by step into each next notch until the pawl reaches the lowest notch 82 at which point the drive to the crank assembly is terminated by disengaging the clutch 83 (FIG. 14) in the drive train 84 to the crank assembly.

To drive the blade down the pawl is turned down by shifting the pin 68 to the down position whereupon the spring 79 biases the pawl against the back edge 85 of this blade and then the pawl steps the blade down by entering above the teeth 82 on the edge 85.

The limit of depth is set by securing the shield by bolt 55 in any of the

openings

55',56,57,58. The shield positively blocks out the notches thus preventing the pawl from engaging extra notches not used at the shallow depths. A second bolt 55" secures the shield in any of the

holes

550, 56a, 57a, or 58a in the blade.

When transporting or digging, the pawl is put in the neutral position to minimize unnecessary wear action on the pawl and blade parts.

Reference is made to FIG. 6 showing the transport location of blade in which the blade is telescoped through the body of the machine.

As best seen in FIGS. 1 and 4, the machine comprises a handle structure 88 connected to the rear side of the casing and extending in normal position upwardly and rearwardly and having a pair of laterally extending handle bars 89,89 which diverge rearwardly and have

handgrips

90,90 at their ends. The front and rear sides of the casing are provided with front and rear transverse horizontal pivot bars 91,92 which are spaced forwardly and rearwardly respectively from the front and rear sides of the casing and connected thereto by

brackets

93,94 respectively. These bars are located in a plane below the axis a,b of the wheel and axle assemblies. In order to introduce the blade into the ground the unit is lifted by the handle and tilted forwardly about the front bar 91 which accommodates a rocking thereon in a clockwise direction as viewed in FIG. 5 until the stop 95 which is mounted on the case above the wheels and projects forwardly from the case engages the ground as at 96. In this position the wheels are lifted off the ground and the blade 27 which has been extended after the unit is in tilted position, engages the ground with its point generally designated 96. It will be appreciated that by the unit being tilted the blade is adapted to be entered into the ground closed to any obstruction such as a utility pole 97 or a wall or the like. The unit is actuated and the blade is caused to move in an elliptical path as seen in FIG. 3 in which the cable 98 is threaded through a longitudinal aperture or bore 99 in a tube 102 welded in the shank portion 100 of the blade. In this construction a slot 101 is cut out of the blade 27 in shank 100 and extends from the lower end of the blade and has its upper end intermediate the ends of the blade. The oval tube 102 is set in the slot against the front and rear edges 103,104 and welded to the blade which is tapered at 105,106 to form a sharp front edge 107 on the lower half of the blade. The point 96 is welded at 107 to the bottom end of the tube 102 and of the shank perpendicular thereto and has a leading forward end portion with downwardly forwardly sloping top surface 108 which converges downwardly with the horizontal bottom side 111 to form sharp forward point edge 112. The point is sheared downwardly rearwardly at its rear 113 to accommodate the rearwardly curved lower rear portion 114 of the pipe or tube 102. The cable is threaded through the bore 99 in tube 102 from the upper end 110 thereof and through the curved lower end portion 114 thereof and exits behind the point whereat it feeds into the trench being made by the blade at the point thereof.

An important feature of the present invention resides in the motion of the digger blade to which in its upstroke portion serves to draw the unit with its multiple wheels or traction means against the ground for improved traction, and also this motion has been found to be more efficient to utilize the engine power. In addition, the motion of the blade plays an important part in incrementally feeding cable including multiple wire from the blade. On the upstroke portion which also travels forward the cable is rendered from the blade with ease and relief. This is true because when the blade moves forward it ejects the most cable, because the blade moves forward to add to the forward velocity of the machine ground drive and this happens at a time when the blade moves upwardly accommodating the maximum relief and large radius for the cable to assume and thus to help prevent the cable from kinking. Then on the downstroke of the blade which also travels rearwardly and helps cancel the forward motion, less cable is ejected at a time when the cable begins to have the lesser ejection radius and on the very down position the surface 116 grips the cable with positive purchase.

In total the cable can move easily down through the blade and unreeled from the reel 117 mounted on the casing or engine as shown. Of course, the cable need not be mounted on the reel but may be laying on the ground and guided manually through the blade which may have the cable guide in the side or may extend from the'top of the blade.

The unit is driven from an engine mounted upon the casing at the forward upper corner thereof. The engine has an output shaft 126 (FIG. 14) driving a pulley 127 about which is trained a drive belt means 129 which drives a pulley 130 connected to an input shaft 131 suitably journalled to the walls of the casing. The belt 129 is clutched and declutched by an idler pulley 132 which is swingably mounted on the casing and operated by the rod and lever linkage 134 which is supported from the handle assembly 88. The shaft 131 drives a gear 135 which meshes with a forward and reverse sliding gear train 137 of conventional construction which provides high, low, and reverse drive ratios with a neutral interval therebetween as controlled by the shift lever 136 projecting rearwardly from the handle structure intermediate its top and bottom ends as best seen in FIG. 7. It will be understood that the gearing as well as the speed ratios and order of selection is of no particular importance in the present invention and the arrangement shown is exemplary and not intended as a limitation. The drive through the selective gear train is delivered to an output shaft 138 which carries a pair of sprockets 139,140, sprocket 139 driving a chain 141 which drives a sprocket 142 connected to rear axle 5 and sprocket drives a chain 144 which drives a sprocket 145 connected to a countershaft 146 journalled in the casing and the countershaft has a sprocket 147 which drives a chain 148 which drives a sprocket 149 connected to the front axle 4.

The drive for the blade operating crank may be from a gear 150 on the input shaft 131 to a gear 152 rotatable on a countershaft 153 journalled from the casing. The gear 152 and shaft 153 are provided with a clutch assembly 154 to connect and disconnect drive from gear 152 with respect to shaft 153 which has a pair of sprockets 155,156 thereon driving chains 157,158 which drive sprockets 159,160 connected to stub

shafts

17 and 18 of the cranks, the free ends of the stub shafts journalled in bearings 161,162 mounted in walls 163,164 of the casing. The clutch is controlled by a lever assembly disposed on the side of the casing.

The operation of the unit in withdrawing the blade close to a building 167 or any other obstruction such as a post, etc., is clearly shown in FIG. 4 wherein the unit is tilted counterclockwise by first rotating it about the rear wheel and axle assembly 5 until the rear pivot bar 92 engages the ground. This is done after the unit is driven as far as it can to the obstruction as shown in phantom (FIG. 4) and then the unit is backed off so to speak, automatically and sufficiently to allow the extended blade (full lines FIG. 4) to swing upwardly out of the ground. The earth closes about the trench and by retracting the blade or manually rendering a sufficient length of cable after which it is cut off the unit is uprighted and driven away utilizing reverse gear, if desired.

EMBODIMENT OF FIG. 15

The structure of the blade and drive components of FIG. 15 is essentially the same as in the previous embodiment except for the arrangement thereof and identical parts are identified by the same reference numbers. In this embodiment the important concept is to drive the blade at its upper end by the crank assembly block 25 and the friction collar 32 slidably embraces the blade intermediate its ends and is pivoted to the ends of the swing links 43,44 which are pivoted at their rear ends on the pin 50 which is connected to a portion 51a of the casing. The action of the pawl and

rack arrangement

63,82 is the same as in the previous arrangement, the pawl being adjustable by the

handlecross pin

74,68 as in the previous embodiment. The important feature of this embodiment is that the elliptical path 175 of the point 96 has its major axis oriented vertically.

EMBODIMENT OF FIG. 16

In FIG. 16 the cable layer is substantially identical with the previous embodiments and the similar parts are identified with the same reference numerals.

In this embodiment a hydraulic tilting ram 200 is provided comprising a cylinder 201 pivoted at its upper end to a side 202 of the casing intermediate its front and rear sides 203,204. The cylinder contains a piston which has rod 205 extending downwardly from the cylinder and provided at its distal end with an arcuate toothed foot 206 secure to the rod by a pin 207. In order to assist tilting the machine the ram is swung toward the front of the machine as seen in FIG. 16 in solid lines to withdraw the blade. The ram being extended by porting hydraulic fluid through line 208 whereby the unit tilts as shown in FIG. 4

The exited position of the unit is shown by illustrating the ram in phantom lines in FIG. 16 and the ground line position at from 210 to 211.

To enter the blade into the ground the retracted ram is swung to a position behind the rear axle and then extended.

It will be understood that although a hydraulic ram is shown any ram such as electric, etc., may be used and is within the scope of this disclosure.

Thus a novel cable laying machine is disclosed as stated in the foregoing objects and which not only obtains improved traction but also or conveniently maneuverable, and in which the blade functions to assist in discharging the cable and the motion of the blade combines the best features of an impact cut and a slicing cut. The machine has a unique organization of parts which permits entry and exit of the blade and thus the cable close to obstructions, particularly important feature heretofore not available inprevious units lacking this compactness;

The construction of the blade and its feed of the cable facilities its ejection reducing power consumption and prevents injury thereto and is capable of laying plural cables.

The parts are arranged to obtain a uniquely balanced unit which distributes the load substantially uniformly on the front and rear axle assemblies and allows a balanced unit thatan average man can handle single handed.

The unit is adapted to pull light plastic tubing or heavy cable which can be attached directly to the rear end of the point 96 at 113 by any suitable means as well known in the art.

Also in withdrawing the blade and cable from the ground, the blade is telescoped into the machine and then can be lowered and driven away without the necessity of reentering the blade into the ground at all to prepare for the next cycle.

It will be understood that the expression traction means is intended to include the

traction wheels

4 and 5 and any other traction devices such as belts or chains and tracks which may be trained about the wheels and tightened thereon such as by overcenter clamps and the like.

EMBODIMENT OF FIGS. 17 25 In the present embodiment parts corresponding to the previous embodiment are identified with the same reference numerals.

It has been found in the testing of the previous embodiments that the longevity of the blade actuating crank block 25 can be greatly increased by tightly locking the block with the blade 27 since the constant high speed vibrations would wear the block through. A

novel blade securing device generally designated 300 is provided comprising a cam 301 which fits between a pair of laterally spaced

ears

302, 302 on the forward end of the block 25. The cam is provided at the forward edge of its lower end 303 with a hook 304 which hooks about a pin 305 extending through and connected with the ears 302. A bolt and nut assembly 307 extends through aperture 308 in the cam and on its forward side draws a washer 309 over the open side 310 of the hook in abutment with the pin. The bolt and nut assembly also secures on the back side of the cam one end of a leaf spring 312, which at its lateral sides engages guides 313, the spring fitting over the cam profile 314 and engaging the forward edge 315 of the blade assembly 27. The upper end of the cam is provided with an aperture 316 which admits the lower end of a spring rod 317 pinned to the block by pin 318. The rod in its unsprung condition diverges upwardly forwardly of the blade assembly and deviates laterally and adjacent to its upper end and is provided with a rearwardly directed lug 320 which upon the rod being loaded in bend rearwardly positions the lug is in lateral alignment with the blade assembly. A pin 321 is inserted through aperture 322 in the lug and apertures in the side straps 28,29 and

links

43,44 of the blade mounting assembly. The spring-back of the rod locks the lug in the annular groove 323 in the pin and the loading on the rod loads the cam into tight engagement with the blade assembly thus eliminating relative movement between the blade and block. The leaf .spring keeps tight tension on the blade when the rod is not locked and/or when the blade is worn.

A further improved feature of this embodiment resides in the provision of an open relief bottom aperture 325 (FIGS. 18-19) at the lower end of tube 102, and the rear edge 326 of the point 96 is rounded and terminates at a location forming a vertical extension of aperture 99 of the tube so that when the blade is withdrawn from the ground as seen in FIG. 5, the cable may be pulled straight down, thus facilitating unloading the cable after the run. The downwardly opening exit also facilitates exit of the cable when hand feeding.

This bottom opening has also proved to minimize or eliminate nicks and damage to the cable without interfering with the function of the curved section 114. Testing has also revealed that the open bottom exit tends to be self cleaning and does not plug with mud or dirt easily.

Another novel feature of the present embodiment resides in the provision of a deflector arrangement comprising a plastic, preferably polypropylene, runner 350 which is in the form of a thin rectangular sheet disposed beneath the unit. A flat sheet backing spring 351 is provided and is secured adjacent to its forward end portion 352 with the forward end portion of the runner to a bracket 353 which is pivotally mounted on a transverse horizontal axis by pivot pins 355 to the forward end supports 356 on the casing 2. The front end portions of the runner and spring overlap the front fulcrum 91.

The runner is provided with a vertical blade-admitting opening generally designated 356' (FIG. 24), which has a narrow front portion 357 complementally formed and snugly admitting the blade therein in the operating position thereon as seen in FIG. 24. The opening 356' has an enlarged rear portion 358 of somewhat oval shape which serves to sift dirt out which may migrate between the blade and the sides 358,359 of the front portion 357. The rear end portion of the runner 360 in operating position overlaps the rear fulcrum 92 as best seen in FIG. 17. Thus the runner is bowed downwardly and serves as a presser to hold down dirt and helps to keep the dirt from erupting upwardly attendant to oscillation of the blade and keeps the turf and ground flat and smooth.

The backing spring is bifurcated intermediate its ends and the legs 362,363 define a rearwardly widening slot 364. The

legs

362 and 363 are bent upwardly and engage respective portions of the bottom of the casing 2 and resist upward deflection of the deflector.

The enlarged rear opening portion 358 also permits pivoting of the deflector out of the way of the blade as seen in FIG. 25 and is sized to permit entry and exit of the foot portion 96.

In addition to the bottom deflector a supplementary deflector 365 is provided on the bottom of the crank block and comprises a flat rear mounting portion 366 which is connected by screws 367 to the bottom 367 of the block. The rear portion is integrated at its front end with a downwardly and forwardly angled bill or combing portion 368 which functions to comb the dirt which works onto the top of the bottom deflector downwardly and rearwardly over the top side 369 of the bottom deflector, pushing such dirt to the enlarged rear exit opening.

Some of the dirt eventually does work over the deflector 365 and flows upwardly through the crank block aperture 12 in the case. This material is worked up over the casing wall 370 and is sifted over the front deflector 371 which is a flap of plastic material such as polypropylene or the like and which is angled downwardly and forwardly. This flap 371 has its rear edge portion 373 secured by screws 374 to the adjacent portion of the casing and the forward portion 375 overlaps the forward end of the bottom flap assembly and directs the dirt to the ground thereinfront.

As best seen in FIGS. 17 and 25, the rear portion 360 of the plastic runner is of extensive length and projects behind the rear fulcrum 92 and is formed with a hook 380 which, when the machine is tipped as in FIG. 25 for removing the blade from the ground, hooks behind fulcrum 92 and the runner bows downwardly as seen in phantom lines in FIG. 25. This occurs because of the cantilever loading of the spring 350 which abuts at its front end 382 through the plastic runner against the front fulcrum 91 ahead of the axis of pivot of the deflector assembly. In such bowed position the runner shifts the enlarged aperture portion 358 in alignment with the blade 27 and permits elevation of the blade and withdrawal of the foot portion thereof.

While this invention has been described in connection with several embodiments, it will be understood that these embodiments are capable of modification and that this application is intended to cover any variations, uses, or adaptations following, in general, the principles of the inventions and including such depar tures from the present disclosures as come within known or customary practice in the art to which the inventions pertain, and as fall within the scope of the invention or the limits of the appended claims.

I claim:

1. A cable laying machine comprising a tractive unit a digger blade carried thereby intermediate its front and rear ends and extensible from a retracted transport position to an operating position whereat said blade extends downwardly below the unit, front and rear fulcrum means projecting from the front and rear ends and providing generally horizontal axes of pivot, handle means extending upwardly rearwardly from the unit, and serving as a lever for manual tipping of the unit about the front fulcrum means to lift the rear end of the unit and thereafter permit extension of the blade in a rearwardly inclined direction so that the blade may be entered into the ground close to an obstruction while the unit being in tilted position is cleared therefrom, said rear fulcrum means accommodating tilting of said unit by the handle upwardly at its front end to thus lift the blade out of the ground close to an obstruction.

2. The invention according to claim 1 and power operated extensible and contractible means on the unit reactive against the ground to facilitate tilting of the unit.

3. The invention according to claim 1 and said blade being substantially centered between the forward and rear ends of the unit.

4. Cable laying apparatus comprising a frame and supporting front and rear powered traction and driving wheel and axle assemblies, and a cable carrying upright digger blade disposed intermediate the front and rear wheel and axle assemblies between the lateral sides thereof in a position to substantially maximize the traction and driving capabilities of said wheel and axle assemblies attendant to the operation of said blade, an engine supported on the frame adjacent to the forward end thereof, a handle structure extending upwardly and rearwardly from the frame, and a gear train mounted on the frame rearwardly of the transverse center line of the frame in counterbalancing relation to the engine whereby the apparatus is essentially balanced across the front and rear wheel and axle assemblies.

5. The invention according to claim 4 and means on the frame disposed outwardly of the front and rear wheel and axle assemblies respectively and providing a fulcrum for tipping the apparatus forwardly and rearwardly, means mounting the blade on the frame for raising and lowering with respect to the frame, and means including a power drive for selectively raising and lowering the blade when the apparatus is tilted for entering the blade into the ground and withdrawing the same from the ground.

6. In a cable and tube laying machine comprising a tractive unit having front and rear wheels, power means on the unit, a cable laying and tube laying digger blade, means for supporting the blade from the unit intermediate the front and rear wheels for cable laying and tube laying movement, and means for transmitting drive from the power means for reciprocating the blade up and down to cut through the soil, fulcrum means disposed at the forward and rear ends of the unit ahead of and behind the front and rear wheels respectively and accommodating tipping of said unit thereabout to respectively enter and withdraw the blade in an arc with respect to the ground.

7. The invention according to claim 6 and laminar shield means beneath said unit having a forward portion mounted to the forward portion of said unit and including a plastic bottom sheet and an overlying spring element abutting the underside of the unit, the plastic element having a rear portion extending over the fulcrum means at the rear of the unit.

8. The invention according to claim 6 and dirt shield means secured beneath said unit and comprising a blade passage therethrough having a front portion shaped complementally to the blade for close confine ment and scouring thereof and having an enlarged communicating rear portion for therethrough behind the blade and accommodating passage of an enlarged foot portion of the blade.

9. The invention according to claim 6 and extensible and retractable means operative between the unit and the ground for tipping said unit.

10. In a cable laying machine comprising a tractive unit, a blade generally vertically mounted thereon having front and rear edges, means for orbiting the blade in an orbital path, said blade having a cable passage therein intermediate its front and rear edges and including a sharply curved segment adjacent to the lower end of the blade convexed downwardly and forwardly and having a rearwardly directed exit, said passage admitting a cable therethrough and said segment operative to grip the cable on the downstroke of the blade and release the cable on the upstroke whereby ejecting the cable through said exit during the upstroke and downstroke portions of movement of the blade, means for driving the blade through abutment therewith and having a sliding connection with the blade whereby the blade is elevated and lowered by sliding relative to said driving means.

11. The invention according to claim 10 and said blade segment having a foot portion including said segment of said passage and said passage having a dirtdischarging openbottom in substantial vertical alignment with the portion of said passage extending longitudinally of the blade to permit straight through withdrawal of the cable without kinking in the passage.

12. In acable laying device, a tractive unit, a cable laying blade carried thereon, means for actuating the blade having a vertical component of movement and sifting dirt cooperating means on the unit and the blade for elevating the blade to transport position and lowering the blade to operating position, means for selectively relating said means to lower and elevate the blade with said actuating means, said cooperative means comprising a series of teeth on the blade and a spring-loaded pawl mounted on theunit for en agement with the teeth and selectively positionable to rive the blade in sald lowering and elevating directions, respectively, and selectively positionable means comprising shield means for covering selected teeth to frustrate entry of the pawl thereinto whereby controlling the operating depth of the blade.

13. A cable and tube laying machine comprising a wheeled framework, a blade mounted on the framework for vertical reciprocation through a vertical aperture therein, a shield having a polypropylene sole portion and an overlaying leaf spring portion reactively engaged with the framework biasing said shield groundwardly, said shield having a blade passage therethrough comprising a forward narrow portion complementally engaging opposite sides of the blade and having an enlarged rear portion for sifting dirt off said shield.

14. A device according to claim 13 and a crank drive for the blade operative in said aperture, and a deflector mounted on the bottom of said crank drive and comprising a front bill portion extending downwardly and forwardly, and said aperture having an open upper end and further deflector means on the framework for guiding dirt exiting from the upper end of the aperture to the ground. 7

15. In a cable and tube laying machine comprising a tractive unitincludinga frame, a cable and tube laying blade mounted on the frame, means for driving the blade comprising a crank block sleeved over the blade intermediate the ends thereof, and means for releasably locking the blade to the block comprising cam means fulcrumed to the block and having means providing a cam profile in engagement with the blade and biasing the same into tight engagement with the block.

16. The invention according to claim 15 and a spring rod connected to said cam means and having means at its end remote from said cam means for securing the rod to the blade and to associated link means.

l7. ln a cable and tube laying device having a wheelsupported frame, a cable and tube laying blade operatively mounted thereon, a runner assembly beneath the frame having passage means with communicating narrow and enlarged portions selectively accommodating the blade therethrough, means for biasing said runner assembly groundwardly, mounting means on the frame supporting said runner assembly for displacement to different positions for selectively aligning the narrow and enlarged portions of the passage means with said blade in operational and nonoperational positions thereof respectively, and means on said assembly releasably limiting the displacement movements of said assembly with respect to said frame.

Claims

8. The invention according to claim 6 and dirt shield means secured beneath said unit and comprising a blade passage therethrough having a front portion shaped complementally to the blade for close confinement and scouring thereof and having an enlarged communicating rear portion for sifting dirt therethrough behind the blade and accommodating passage of an enlarged foot portion of the blade.

11. The invention according to claim 10 and said blade segment having a foot portion including said segment of said passage and said passage having a dirt-discharging open bottom in substantial vertical alignment with the portion of said passage extending longitudinally of the blade to permit straight through withdrawal of the cable without kinking in the passage.

12. In a cable laying device, a tractive unit, a cable laying blade carried thereon, means for actuating the blade having a vertical component of movement and cooperating means on the unit and the blade for elevating the blade to transport position and lowering the blade to operating position, means for selectively relating said means to lower and elevate the blade with said actuating means, said cooperative means comprising a series of teeth on the blade and a spring-loaded pawl mounted on the unit for engagement with the teeth and selectively positionable to drive the blade in said lowering and elevating directions, respectively, and selectively positionable means comprising shield means for covering selected teeth to frustrate entry of the pawl thereinto whereby controlling the operating depth of the blade.

14. A device according to claim 13 and a crank drive for the blade operative in said aperture, and a deflector mounted on the bottom of said crank drive and comprising a front bill portion extending downwardly and forwardly, and said aperture having an open upper end and further deflector means on the framework for guiding dirt exiting from the upper end of the aperture to the ground.

15. In a cable and tube laying machine comprising a tractive unit including a frame, a cable and tube laying blade mounted on the frame, means for driving the blade comprising a crank block sleeved over the blade intermediate the ends thereof, and means for releasably locking the blade to the block comprising cam means fulcrumed to the block and having means providing a cam profile in engagement with the blade and biasing the same into tight engagement with the block.