US3015261A

US3015261A - Trench filling and shoulder spreading machine

Info

Publication number: US3015261A
Application number: US730943A
Authority: US
Inventors: Raymore D Macdonald
Original assignee: Ulrich Manufacturing Co
Current assignee: Ulrich Manufacturing Co
Priority date: 1958-04-25
Filing date: 1958-04-25
Publication date: 1962-01-02
Anticipated expiration: 1979-01-02

Description

Jan. 2, 1962 Filed April 25,

R. D. M DONALD 3,015,261

TRENCH FILLING AND snowman SPREADING MACHINE 1958 13 Sheets-Sheet 1 INVENTOR.

I I @yzmi QM Jan 2, 1962 MacDoNALD 3,015,261

TRENCH FILLING AND SHOULDER SPREADING MACHINE Filed April 25, 1958 13 Sheets-Sheet 3 a a w 00 & T

49 JM, Am

Jan. 2, 1962 R. D. MHC'DONALD 3,015,251

TRENCH FILLING AND SHOULDER SPREADING MACHINE Filed April 25, 1958 13 Sheets-Sheet 4 Jan. 2, 1962 R. D. M DONALD 3,015,251

NCH FILLING AND SHOULDER SPREADING MACHINE Fi lllll ril 25, 1958 13 Sheets-Sheet 5 Jan. 2, 1962 3,015,261

TREILICH FILLING AND SHOULDER SPREADING MACHINE R. D. M DQNALD l3 Sheets-Sheet 6 Filed April 25, 1958 QQ mQ Jan. 2, 1962 R. D. M DONALD 3,015,261

TRENCH FILLING AND SHOULDER SPREADING MACHINE l3 Sheets-Sheet 7 Filed April 25, 1958 Jan. 2, 1962 R. D. M DONALD 3,015,251

TRENCH FILLING AND SHOULDER SPREADING MACHINE 13 Sheets-Sheet 8 Filed April 25, 1958 Jan. 2, 1962 R. o. M DONALD 3,015,261

TRENCH FILLING AND SHOULDER SPREADING MACHINE Filed April 25, 1958 13 Sheets-Sheet 9 INVENTOR.

Jan. 2, 1962 R. D. M DO NALD 3,015,261

TRENCH FILLING AND SHOULDER SPREADING MACHINE Filed April 25, 1958 115 Sheets-Sheet 10 INVENTOR.

Jan. 2, 1962 R. D. M DONALD 3,015,251

TRENCH FILLING AND SHOULDER SPREADING MACHINE l3 Sheets-Sheet 11 Filed April 25, 1958 INVENTOR- Eqynzore D fifczoflarzald, 1M,

Jan. 2, 1962 R. D. M DONALD TRENCH FILLING AND SHOULDER SPREADING MACHINE 13 Sheets-Sheet 12 Filed April 25, 1958 INVENTOR. ji /more D jiac 507M Jan. 2, 1962 R. D. M DONALD 3,015,261

TRENCH FILLING AND SHOULDER SPREADING MACHINE l3 Sheets-Sheet 13 Filed April 25, 1958 @marezzmgi BY nrg fi United States Patent C) 3,015,261 TRENCH FlLLING AND SHOULDER SPREADING MACHINE Raymore D. MacDonald, Eureka, IlL, assignor to Ulrich Manufacturing (30., Roanoke, 111., a corporation of Delaware Filed Apr. 25, 1958, Ser. No. 730,943 16 Claims. (Cl. 94-46) The present invention relates to that class of road construction machines commonly known as trench'filling and shoulder spreading machines, which are frequently employed in road widening operations. In these road widening operations, it is a conventional practice to first cut a longitudinal trench out of the soil along one side edge or margin of an existing road composed of concrete, macadam or other road material, following which this trench is filled with bituminous mix, crushed stone, gravel, concrete or other desired filling material, such filling operation being performed by a trench filling machine. The width of the fill is dependent upon the extent to which it is desired to widen the road, and the depth of the fill is dependent upon the depth of road bed desired, the filling material used, whether the new fill and the existing road is to be resurfaced, etc.

Road construction machines of this general type are also employed in shoulder work in which a widened shoulder is spread along the side edge of an existing road by spreading bituminous mix, crushed stone, etc. along this side edge. In this regard, the present machine herein disclosed is not limited in use to trench filling operations, but is also capable of shoulder work in which a widened shoulder is spread along the edge of an existing road by spreading black top, crushed stone, etc. to a controlled depth, slope or grade.

One of the principal objects of the invention is to provide an improved trench filling and shoulder spreading machine which is constructed in the form of an attachment unit for quick and easy attachment to and detachment from a conventional motor grader. The conventional motor grader thus serves as the prime mover or power vehicle for propelling my improved attachment unit along the roadway in the trench filling or shoulder spreading operation. Considering the range of equipment owned by the average road building contractor or road maintenance contractor, the conventional motor grader is generally the primary motorized vehicle, or is one of the most prevalent pieces of equipment in the entire road working field. Thus, by constructing my improved machine for attachment to a motor grader, I avoid the much greater initial cost and maintenance cost of a completely self-propelled machine; and I also obtain increased productive capacity and other operating advantages which stem from the use with the motor grader.

For example, the strike-off blade action of the attachment unit sets up a very large diagonally acting side draft, but the relatively long wheel base of the motor grader and its great resistance to side draft effectively resists this side draft set up in the strike-off blade of the attachment unit.

According to the improved coupling arrangement herein disclosed, my improved attachment unit is coupled up to the front end of the motorgrader to be pushed ahead of the grader. Theattachment unit has a hopper at its front end which receives the fill material from successive dump trucks which move into dumping position ahead of the attachment unit and dump their material from the rear ends of their dumping bodies into the hopper. In order that the operation of dumping the material from the dump body of the truck into the hopper of the attachment unit can be effected without stopping the forward motion of the attachment unit it is usually necessary to maintain pushing contact between the attachment unit and each dumping truck, whereby the attachment unit pushes the dumping truck ahead of it. Therelatively large traction power available from the motor grader affords sufficient power to push the largest size of dump truck ahead of the attachment unit in the truck dumping operation, even up the steepest grades.

Another object of the invention is to provide an improved attachment unit adapted for attachment to a conventional motor grader wherein the strike-oft blade of the unit is connected to be governed and controlled by the scraper blade of the conventional motor grader. As is well known, the scraper blade of the conventional motor grader is capable of a wide variety of positioning adjustments, such as: (1) raising and lowering of the scraper blade; (2) horizontal rotation of the blade around the vertical axis of the blade supporting circle; (3) lateral tilting of the blade by raising and lowering opposite sides of the circle; (4) side shifting of the blade and blade circle, etc. Most or all of these positioning adjustments of the scraper blade are performed by mechanical or hydraulic power in the later designs of motor graders, and the mounting and adjustments of the scraper blade are capable of withstanding the extremely large stresses which are encountered by the scraper blade in the ordinary performance of a grading operation by the motor grader. I make these various adjustments of the scraper blade and its sturdiness of mounting available to the strike-off blade of my attachment unit by connecting the outer end of the strike-off blade with the scraper blade, so that this outer end of the strike-ofi blade responds to adjustments given to the scraper blade of the grader. The inner end of the strike-off blade of my trench filling and shoulder spreading machine is preferably made responsive to a separate and independent control located on this filling and spreading machine, but, as above stated, the outer end of such strike-off blade is positively connected with and made responsive to the scraper blade of the grader. Thus, it Will be seen that by making the outer end of the strike-0E blade of 'my machine responsive to positioning adjustments of the scraper blade of the motor grader, I can efiect all of the necessary power operated adjustments of the outer end of the strike-ofii blade, through the motor grader, without burdening the attachment unit with the substantial cost, complication and weight of providing such power operated adjustments on the attachment unit. Still further, as above intimated, I utilize the very large side draft resistance inherent in the motor grader to sustain the side draft set up in the outer end of the strike-oil? blade of my attachment machine. In this regard, the above described feature of pushing the attachment unit ahead of the motor grader constitutes a very important factor in being able to establish the desired adjusting and side draft transmitting connection between the scraper blade of the motor grader and the strike-01f blade of the attachment unit, whereby the outer end of the strike-off blade is made responsive to controls effected through the scraper blade, and also has its side draft borne by the scraper blade.

Another object of the invention is to provide an improved three-point mounting or suspension of the attachment unit. These three points comprise two laterally spaced caster wheel sets at the front of the attachment unit, and'a ball-and-socket mounting joint between the rear portion of the attachment unit'and the front end of the motor grader. This three point mounting of the attachment unit, with the universal joint type of draft transmitting connection between the attachment unit and the motor grader, permits relative transverse rocking movement between the attachment unit and the motor grader,

each independently of theother, as the two vehicles pass over uneven road surfaces. A pivotally acting stabilizer brace extends between the motor grader and the attachment unit, preferably having a ball-and-socket connection at its front end with the attachment unit. This stabilizer brace compels the attachment unit to steer directly with the front end of the motor grader, and supplements the draft transmitting action of the ball-and-socket mounting joint, while still permitting the free transverse rocking movement between the attachment unit and motor grader. This free tranverse rocking movement results in the strike-off blade being more accurately maintained at its predetermined set height of strike-off of the filling material, as will be later described. This free transverse rocking movement also avoids the transmission of twisting, racking stresses from the frame of the motor grader to the. frame of the attachment unit, or vice versa.

Another object of the invention is to provide an improved lifting jack, preferably hydraulic in its operation, for manually lifting and lowering the rear end of the attachment unit in performing the manual operation of coupling and uncoupling the attachment unit and the motor grader at the ball-and-socket mounting joint.

The trench filling and shoulder spreading unit has "a conveyor belt traveling in the bottom of the material receiving hopper of the unit for discharging this material along the side edge of the road; and another object of the invention is to provide improved regulating means for regulating the speed of travel of this conveyor belt through infinitely small speed changes. Thus, it is possible for the operator to regulate very closely the rate of discharge of the. filling material to take care of different depths and widths of fill and different operating conditions.

Another object of the invention is'to provide an improved hydraulically tilted dump apron or front hopper wall at the front edge of the material receiving hopper, which can be readily raised and lowered by the operator for the purpose of accommodating different body heights of different dump trucks, and also for the purpose of increasing the hopper capacity. This tiltable dump apron increases the capacity of the hopper by providing a front hopper wall which can be disposed substantially horizontally for receiving material during the truck dumping operation, and which can thereafter be tilted upwardly to discharge the material resting thereon rearwardly back to the conveyor belt.

' Another object is to provide an improved design of hinged trench and curb seal which will prevent material from being carried from the trench back under the rna chine on to thepavement; and which can also be readily folded up out of the trench when the machine is in transport.

Further objects of the invention pertaining to the conveyor belt of the machine are to provide improved selfcleaning conveyor belt seals which are tapered so as to be self-relieving in the direction of travel; to provide an improved floating type of inside belt scraper at the tail pulley of the belt; and to provide an improved arrangement of clean-out holes in the sides of the conveyor belt channel.

. Still another object is to provide the machine with an improved frame construction characterized by a trans versely'extending frame tube which functions firstly as the backbone of the frame; secondly it serves as an oil reservoir adapted to store a large quantity of oil for the hydraulic drive' and control systems; and thirdly because 7 front portion of a conventional motor grader and showing the trench filling embodiment of my improved attachment unit coupled thereto, this trench filling embodiment being designated AU.

FIGURE 13 is a similar view showing the shoulder spreading embodiment of the attached front unit, coupled to the conventional motor grader, this shoulder spreading embodiment being designated AU.

FIGURE 2 is a perspective view of the rear end of the attachment unit having the trench filling equipment mounted thereon, showing it uncoupled from the motor grader.

FIGURE 3 is a fragmentary rear elevational view of most of one of the attachment units, showing it uncoupled from the motor grader similarly to FIGURE 2.

FIGURE 4 is a fragmentary perspective view of the left hand portion of the trench filling embodiment of attachment unit AU, showing the front and left hand side thereof.

FIGURE 5 is a side elevational view of the trench filling embodiment AU, showing the strike-'ofi box in its lowered position in a trench.

FIGURE 6 is a somewhat similar view of this same trench filling embodiment, AU on a slightly smaller scale, with the strike-01f box removed or broken away to illustrate more clearly the point of discharge of the fill ma terial from the machine, this view also illustrating fragmentarily the rear end of a dump truck in the act of dumping fill material into the hopper.

FIGURE 6A is a view quite similar to FIGURE 6, but of the shoulder spreading embodiment AU.

FIGURE 7 is an isolated fragmentary plan view of the stabilizer bar which is connected between either of the two attachment units AU, AU, and the motor grader.

FIGURE 8 is a plan view of an'irnproved floating type of inside belt scraper used on either embodiment AU or AU, this view being on a largerscale.

FIGURE 9 is afragmentary elevational view of my improved design of hinged trench and curb seal used on either embodiment.

FIGURE 10 is a transverse sectional view through the same, taken approximately on the plane of the line 10- 10 of FIGURE 9.

FIGURE 11 is a detail section taken on the plane of the line 11-.11 of FIGURE 5.

FIGURE 12 is a fragmentary side elevational view of the intermediate portion of the conventional motor grader MG illustrated in FIGURES 1A and 1B, but on a' larger scale, and FIGURE 13 is a fragmentary transverse sectional view taken on the plane of the line 13-43 of FIG- URE 12, these two figures showing in greater detail certain of the conventional controls ordinarily utilized for efiecting lifting, lowering and lateral shifting adjusting movements of the conventional scraper blade of such a grader, which adjusting movements are transmitted from such scraper blade to the strike-off blade' of the shoulder spreading attachment unit AU of FIGURE 1A.

' FIGURE 14 is a' fragmentary elevational view of part 'of said shoulder spreading attachment unit AU, corresponding to a section taken approximately on the plane of the line 14- 14 of FIGURE 1A, showing the vertically moving hydraulically operated slide, together with the flinging articulation and pivoting articulation of the inner end of the strike-off blade of said shoulder spreading attachment unit AU.

FIGURE 15 is a fragmentary plan view of FIGURE 14. FIGURE 15A is a detail section of FIGUREIS. FIGURE 16 is a fragmentary elevational view, corresponding to a view taken on the plane of the line 1616 of FIGURE 1B, showing the extensible boom for connecting the scraper blade ofjthe motor grader with the strike-01f blade of the shoulder spreading attachment unit AU.

FIGURE 17 is a fragmentary plan view of FIGURE 16. FIGURE 18 is a fragmentary elevational view, corresponding to a view taken on the plane of the line 18. 13

of FIGURE 1B, showing the margin defining plate and the shoe plate at the outer end of the strike-off blade.

FIGURE 19 is a plan view of FIGURE -18.

FIGURE 20 is a fragmentary detail view showing in vertical section the ball and socket transversely rockable mounting joint which couples the rear portion of the attachment unit to the front end of the motor grader, and;

FIGURE 21 is a transverse detail sectional view taken approximately on the plane of the line 21-21 of FIG- URE 20.

In FIGURE 1A I have shown the trench filling embodiment of my attachment unit, designated AU in its entirety, and in FIGURE 13 I have shown the shoulder spreading embodiment of my attachment unit, designated AU in its entirety. Both attachment units are quite similar up to the point of discharge of the fill material from the conveyor belt, following which the trench filling embodiment causes the fill material to fill a previously cut trench along the side of the road, whereas the shoulder spreading embodiment causes the fill material to be spread outwardly from the side of the road, usually over a substantial span, to build up the shoulder along side the road. Both attachment units are to be coupled to the front end of any conventional or standard motor grader, which is designated MG in its entirety. The attachment unit AU or AU is adapted to receive its filling material from successive dump trucks which are pushed ahead of the attachment unit and which dump rearwardly into the material receiving hopper of the unit, the rear end of one of such dump trucks being indicated fragmentarily at DT in FIGURE 6.

Because of the close collaboration of the motor grader MG with each of the attachment units AU, AU I shall first briefly describe the main parts of a conventional motor grader. It usually comprises a suitable frame structure 25 supported at its front end on front steering wheels 26 and at its rear end on rear driving wheels 27. The rear driving wheels are generally but not necessarily in tandem pairs. An internal combustion engine 29 operates to drive the rear driving wheels 27 and also the accessories, such as the oil pump of the hydraulic control system; and in the case of a six wheel drive motor grader this engine also serves to drive the front steering wheels 26. Located under the frame 25 between the front wheels 26 and rear wheels 27 is the conventional scraper blade 36 which is so mounted and connected with the frame 25 as to be capable of a wide variety of positioning adjustments. For example, the blade is mounted on a so-called circle 31 having a substantially vertical rotative axis which enables the scraper blade to be rotated in a substantially horizontal plane to different horizontal angles under the frame 25. The horizontal rotation of the blade around the axis of the circle 31 is usually performed by an engine drive into a gear box, as is well known. The scraper blade 30 and circle 31 are also capable of a sideshifting adjustment, usually performed by the energization of hydraulic rams or mechanical linkage in a well known manner, so as to enable either end of the scraper blade 30 to be projected out to a greater or lesser distance to each side of the frame 25. Moreover, the circle 31 can be tilted around a fore and aft axis extending substantially longitudinally of the grader, as by the energization of hydraulic rams or mechanical drive, in a well known manner, so that either side of the circle can be tilted up- .wardly or downwardly, whereby the corresponding end of the scraper blade can also be tilted upwardly or downwardly as desired. Still further, the entire assembly of the circle and blade can be raised and lowered to vary the cutting depth of the blade, and to swing the blade up to a raised inoperative position, as by the operation of the hydraulic rams or mechanical linkage, as is well known. In the later designs of motor graders, all of these blade positioning adjustments are effected in re-- sponse to the operation of control levers or the like 36 located at the operator's position 37 on the motor grader.

These lifting, lowering, tilting and side shifting adjustments of the scraper blade 30 of the motor grader are utilized in effecting adjustments of the outer end of the strike-off blade of the shoulder spreading attachment unit AU, and will be described in greater detail later, preliminary to the description of this shoulder spreading attachment unit. Both embodiments of attachment units AU and AU have preferably been constructed and proportioned for use particularly in conjunction with six wheel motor graders having tandem pairs of rear driving wheels 27 and having front steering wheels 26 which may or may not be power driven, and the same or a comparable grader is illustrated in the drawings, but it will of course be understood that the invention is not limited to use with either of these specific graders.

Referring now to the main features forming the structural basis of both embodiments AU and AU, and with particular reference first to FIGURES 2, 3, 5, 6 and 7, it will be seen that the main frame thereof is of torque tube and box section design comprising at the rear a transversely extending horizontal tank tube '40 which constitutes the main back-bone of the frame. This tank tube 40 functions as an oil reservoir for storing a reserve quantity of oil for the hydraulic drive and hydraulic control system, and in this regard the large surface area of such tank tube functions effectively to dissipate the heat from the circulating oil. The ends of the tank tube 40 are closed by removable end heads 41, the removal of which affords access to the interior of the tank tube for cleaning the latter.

Welded to the underside of the tank tube 40 substantially at its center is the downwardly extending mounting bracket 43 having a spherical socket 44 formed in its underside. Secured to and projecting from the front end of the motor grader MG is an upwardly extending ball 45 which is adapted to establish a ball-andsocket mounting joint within the spherical socket 44. A removable cap 46 having a spherical pocket in its upper surface is detachably secured by belts or cap screws 47 to the underside of the mounting bracket 43. This ball and socket mounting joint 44, 45, the details of which are best shown in FIGURES 20 and 21, constitutes the main draft transmitting connection between the motor grader MG and the attachment unit AU, and it will be seen that by the mere removal of the bolts or cap screws 47 this draft transmitting connection can be easily separated for uncoupling the attachment unit from the motor grader. The shank of the mounting ball 45 is welded to a cross plate 49 which in turn has its ends welded to a pair of laterally spaced links 51 extending upwardly and rearwardly therefrom. The rear ends of these pivoting links 51 engage over opposite ends of a transversely extending boss 52 formed integral with the front end of the motor grader frame, and a transverse pivot pin 53 passes through the pivoting links 51 and boss 52. Welded to the underside of the plate 49 and extending downwardly therefrom is a pair of laterally spaced arms 55 having a transversely extending plate 56 welded to their lower ends and projecting laterally beyond the arms. A U-shaped clevis 57 has its spaced ends passing through loose fitting holes in the projecting end portions of the plate 56, and nuts 58 screw over threads on the ends of the clevis. The clevis 57 embraces a curved arm or web 61 formed integral with the front end of the motor grader frame. By loosening the nuts 58 the clevis 57 may be shifted upwardly or downwardly along the curved arm 61 for raising or lowering the mounting height of the ball 45 with respect to the front end of the motor grader frame. If desired, an adjusting screw 62 may be threaded through a tapped hole in the plate 56 between the spaced arms 55, by the adjustment of which screw the rear surface of plate 56 can be adjusted toward or away from the curved front surface of the arcuate web 61, thereby raising or lowering the height of the ball 45.

'The frame of the attachment unit AU also comprises ing transverse pivot pins or axles 69 on which one or more caster wheels 70 are mounted. The two laterally spaced caster wheel sets 70, 70 constitute two spaced points of support for the front end of the attachment unit frame,

and the ball-and-socket mounting joint 44, 45 constitutes a third laterally rockable point of support for the rear end of the attachment unit frame. It will be evident that the ball-and-socket mounting joint 44, 45 permits independent transverse rocking movement between the motor grader MG and the attachment unit AU as the two vehicles pass over uneven road surfaces. I have found it preferable to use solid rubber tires on the caster wheels 70 so as to avoid the rise and fall of the strike-off blade level to which pneumatic tires are subject with different loads in the.

hopper. The solid rubber tires also enable single caster wheels to be used in many instances, as shown in FIG- URE 4, instead of pairs.

Extending between the right hand side of each of the attachment units AU and AU and a rearwardly disposed point of themotor grader MG is a pivotally acting stabilizer brace 72, which compels the attachment unit to steer directly with the front end of the motor grader (as permitted by the castering action of the wheels 70) and which also supplements the draft transmitting action of the ball-and-socket mounting joint 44, 45, while still per mitting the aforesaid free transverse rocking movement between the attachment unit and the motor grader. As shown in FIGURE 7, this stabilizer brace 72 is preferably in the form of a long tube having a readily releasable bal'-and-socketconnection at its front end with the right hand end of the tank tube 40. This ball-and-socket connection comprises front and rear halves 74 and 75 of a spherical socket 76 adapted to engage over a ball 77 which projectsupwardly from the right hand end of the tank tube 40. The rear socket half 75 is secured to the front end of the stabilizer tube 72, and the front socket half 74 is releasably secured to the rear socket half-over the, ball 77-by two or more bolts or cap screws 78. This permits the ready disconnection of the stabilizer brace 72 when the attachment unit is to be uncoupled from the URES 1A, 1B and 3 that the single point axis of this ball and socket joint lies in the longitudinal central vertical plane passing through both the motor grader MG and the, attachment .unit AU. or AU; as indicated by the dash-dot lines P-P in FiGURES 1A and 1B. This plane P-P passes midway in the tread spans of all. four pairs of wheels, namely the two pairs ofrear driving wheels 27-27 of the motor grader MG, the pair of front steering wheels 26-26 of the motor grader, and the front caster wheels 70-70 of the attachment unit AU or AU. The freedom of the two vehicles MG and AU-AU' to have this relative transverse rocking movementis not hindered in any sense by the presence of the long'diagonal stabilizing bar 72, the opposite ends of'this stabilizer bar merely rising or falling relatively to each other in accommodating opposite directions of relative transverse rocking movement between the two vehicles. If desired, a duplicate stabilizing bar 72'may be arranged on the other side of 3 the longitudinal -plane"P-P, comparable to a'wish-bone relation, but I find that a single stabilizing bar isentirely adequate. As previously described, this stabilizing bar compels the attachment unit to steer. directly with the front end of the motor grader, as permitted by the castering action of the front attachment unit wheels 70; and the stabilizing bar also supplements the draft transmitting action of the ball and socket mounting joint 44-45, while still permitting the aforesaid free transverse rockingmovement between the two vehicles around a longitudinal axis lying in the central vertical plane PP. Such freedom of the two vehicles to have this relative transverse rocking movement therebetween results in the strike-off box 175 or the strike-off blade 275 (to be later described) being more accurately maintained at its respective predetermined height of strike-off of the filling material, irrespective of any pronounced undulations in the road surface encountered by the

vehicle wheels

27, 26 or 70. For example, if the left hand rear traction wheels 27 of the motor grader MG should drop into a hole or depression along the left hand edge of the road, or should drop off this edge of the road, this would immediately tend to cock or twist the grader frame to bring the left hand side of the entire length of the frame down to a lower level than the right hand side. Let us assume that the attachment unit AU-AU' was coupled to the motor grader MG in some such coupled relation that the free, transverse rocking movement afforded by the transversely rockable joint 44-45 could not occur, then there would be a tendency to transmit the entire cocking or twisting of the grader frame to the frame of the attachment unit AU. This could very well tend to depress the inner side or inner end of the laterally projecting strike-off box or strike-off blade through a substantial degree of downward movement below the predetermined set strike-off level, with the result that a substantially lesser depth of material wouldrbe laid along this part of the road. This downward stressing of the strike-off side might be augmented at times by the overhanging weight of a long length of outwardly extending strike-off blade.

Now let us assume the present situation wherein the two vehicle frames are connected together by the cenrally aligned transversely rockable joint 44-45. In such a situation no part of the transverse cocking or twisting which is acting through the grader frame can be transmitted to the attachment unit frame; Also, only one-half of the downward vertical component caused in the left hand side of the grade frame, by the left hand rear grader wheels dropping into a hole, will be transmitted as a downward component to the rear edge of the attachment unit tending to swing this edge of the attachment unit downwardly around the front caster wheels 70-70. The transmission of this downward'component from the grader frame to the attachment unit frame is reduced to'one-half 'by reason of the fact that the transversely rockable joint 44-45 only transmits to the attachment unit frame onehalf of the downward component occurring in the grader frame because the line of action of the transversely rockable joint 4445 lies in the central plane P-P, which is exactly one-half or is midway of the distance between each pair of companion wheels. Thus, in the present instanceunder discussion, the attachment unit frame receives no twisting stress, and the inner side or inner end of the strike-off box or blade is only depressed one-half as far as in the other instance where there is no transversely rockable joint between the two vehicle frames.

This would also be true in the reverse situation of the right'hand rear traction wheels 27 dropping into a hole or depression on their side of the road.

' It will also be seen from the foregoing that the abovedescribed action of the transversely rockable joint 44-45 in avoiding the transmission of twisting stresses from one vehicle to the other, also avoids the transmission of racking and twisting stresses from the frameof the attachment unit to the frame of the motor grader or other propelling vehicle. These racking,.twisting stresses are very likely to occur when this shoulder spreading or two vehicle assembly is in transport, traveling at speeds ranging up to 20 miles per hour or more, and over considerable distances; or when the two vehicles are passing over bridges, around culverts, or driving over irregular ground. Also, these stresses are almost bound to occur when turning the two vehicle assembly around at the end of a shoulder-spreading run or pass along one edge of a road, possibly for making another shoulder-spreading run back in the opposite direction along the opposite side of the road, this operation of turning around almost inevitably occurring over some rough ground in view of the fact that the overall length of the shoulder spreading vehicle assembly is in the neighborhood of 30 feet. While the fore and aft axis of the single point transversely rockable balland-socket joint 44-45 preferably lies on the central longitudinal plane PP of the two vehicles (FIGURES 1A, 1B), for obtaining the maximum benefits and advantages pointed out above, nevertheless this fore-and-aft axis of this transversely rockable joint 4445 might not be centrally disposed on the central plane P-P, but might be offset therefrom toward either the right or left wheel lines of the two vehicles, possibly with some sacrifice of certain of the aforementioned benefits and advantages. The stabilizing bar 72 would continue to be used with any such offset location of the transversely rockable draft transmitting joint.

When the attachment unit AU or AU is uncoupled from the motor grader by the separation of the balland-socket mounting joint 44, 45, and the disconnection of the stabilizer brace 72, the weight of the rear end of the attachment unit is brought to bear on a jack roller or wheel 82 which is lowered into engagement with the road surface for taking this weight of the rear end of the attachment unit AU or AU off of the ball-and-socket mounting 44, 45 to facilitate disconnection of such mounting; and this rear roller 82 may also be employed to support the rear end of the attachment unit in 21 normal or raised position while the attachment unit is standing idle, disconnected from the motor grader MG. While these are the preferred utilities of this rear roller 82, it may also be employed to support substantially all or part of the weight of the rear end of the attachment unit AU or AU while the latter is being propelled forwardly in the trench filling or shoulder spreading operation, as I shall presently describe. This jack roller 82 is pivoted at 83 between the side arms of a mounting clevis 84 which is secured to the rear end of a vertically swinging arm or yoke frame 85. The front end of the arm or yoke frame 85 has wide-axis mounting on a pivot pin or pins 86 supported in pivot lugs 87 projecting from the trench filler frame. Welded to the underside of the tank tube 49 and extending downwardly therefrom is a rigid jack leg 91 having a clevis shaped lower end 92 carrying a transverse pivot pin 93. Pivoted on the pin 93 is a pivot block 94 at the upper end of a piston rod 95 which extends downwardly into the cylinder 96 of a one way or single action hydraulic jack 97. Projecting from the lower end of the cylinder 96 is a pivot block 98 which is mounted on a transverse pivot pin 99 extending through the upper portion of the clevis 84. One or more return springs 100 are connected between the clevis 84 and the upper portion of the frame for normally holding the jack roller or wheel 82 elevated. When the attachment unit is in its coupled relation to the motor grader MG, with the mounting ball 45 seating in the mounting socket 44, the jack roller or wheel 82 may be held in an elevated position out of contact with the road surface by the action of the tension springs 100, unless it is desired that this rear roller 82 sustain part of the weight of the rear end of the attachment unit AU while the latter is in operation in a trench filling or in a shoulder spreading operation. When it is desired to uncouple the attachment unit AU or AU from the motor grader, hydraulic pressure is caused to act in the hydraulic jack 97 for forcing the jack roller 82 downwardly against the roadsurface, thereby elevating the rear end of the attachment unit frame and enabling the mounting socket 44 to be easily lifted off of the mounting ball 45. The rear end of the attachment unit frame may be maintained in this elevated position by the hydraulic jack 97 during the entire time that it is uncoupled from the motor grader, or the rear end of the attachment unit frame may be lowered for resting on a suitable support other than the hydraulically maintained position of the jack roller 82. A small hand operated hydraulic pump 101 is mounted adjacent to the hydraulic jack 97 and is hydraulically connected therewith, so that the rear end of the attachment unit can be raised and lowered by the hand operation of the manually operated pump 101 and its conventional relief valve. When it is desired to have this roller 82 carry part or all of the weight of the rear end of the attachment unit AU during the trench filling or shoulder spreading operation, the hydraulic pump 101 is manually operated to force the roller down against the road surface with sufiicient pressure to support any desired proportion of the weight of the rear end of the attachment unit AU, the hydraulic characteristics of the jack 97 locking the wheel 82 in this lowered rolling position. Because of the fact that it is only a single wheel and because of its location quite close to the fore and aft center line of the attachment unit AU, well between the front steering wheels 26-26 of the motor grader MG, it follows that this supporting roller or wheel 82 will track or follow sufficiently well during any of the steering movements of the motor grader and attachment unit, which are always on a large radius owing to the long wheel base of the combined vehicles.

Located between the tranversely extending rear and front frame tubes 40 and 65 a material receiving hopper 105 into which is dumped the hot or cold asphaltic mix, crushed rock, gravel or other material used in making the trench fill. This hopper comprises side walls 106, 106', a sloping rear wall 107, and a hydraulically operated vertically swinging dump apron or front hopper wall 108 (FIGURE 6) at the front edge of the hopper. This hydraulically operated dump apron or wall 108 comprises a transversely extending plate or wall 109 extending substantially from side wall to side wall of the hopper, and having a hinged rear edge which is pivotally mounted on a transversely extending pivot rod 111 secured to the frame. The front edge of the plate 109 is formed with an upwardly bent lip 112 to which is secured an upwardly extending section of pliable belting or webbing 113 adapted to strike the underside of the dump truck body. Projecting downwardly from the underside of the apron plate 109 substantially at its center are spaced pivot brackets or plates 115 carrying a pivot pin 116 therebetween, on which is pivoted an eye or clevis 117 secured to the upper end of a piston rod 118. This piston rod extends into a double acting hydraulic cylinder 119 which are pivotally connected at 120 at its lower end to the frame of the machine. This front hopper wall 108 normally occupies the relatively fiat position shown in full lines in FIGURE 6. In the truck dumping operation, this front hopper wall 108 can, if desired, be swung upwardly by energizing the hydraulic ram 119 to bring the pliable upper edge 113 into engagement against the underside of the dumping truck body while the latter is tilting rearwardly in the performance of the dumping operation. In this manner, the fill material is prevented from spilling forwardly between-the under side of the truck body and the hopper 105, irrespective ofwhether it is a high dump truck or a lowone. After the dump truck has pulled away this front hopper wall 108 is given an upward tilting movement for dumping all of the material which has been dumped thereon by the truck, this rriaterial being carried up to an angle considerably beyond the angle of repose for discharge rearwardly toward the conveyor belt. It will thus be seen that the tiltableapron or WaJl 10 8, in its normal forwardly extending position, considerably increases the effective capacity of the hopper. Also, by

virtue of the hydraulic cylinder operation of the filtable apron 168 it can be utilized to release or free sticky blacktop or like material which may tend to adhere within'the body of the dump truck even after the truck body has been raised to its maximum angle of tilt. This load releasing operation is performed by suddenly admitting full hydraulic pressure to the ram 119 for causing the apron 108 to swing up with a quick motion so as to strike the underside of the tilted truck body with a sharp blow; or it may be performed by causing the apron to slowly lift the entire truck body when in its til-ted position, and to then sharply drop the'truck body to shake the load loose. Material adhering to the hydraulically operated apron 108 may also be shaken loose by quickly operating the hydraulic ram 119 in opposite directions, with the motion suddenly interrupted in each direction by the piston of the ram 119 striking the opposite ends of the ram cylinder, or the gate striking opposite end stops.

Rotatably mounted at the front edge of the machine are two horizontally disposed pusher rollers 122 122, whichare adapted to engage the rear wheels 123 of the dump truck for pushing the dump truck DT ahead of the attachment unit. AU or AU while the dump truck is dumping fill material into the hopper 105 during continuous forward movement of the attachment unit. These two rollers 122 are spaced apart a distance corresponding to the tread span of the rear wheels of the conventional dump truck. In regard to tread span, it should be noted that the tread span between the two caster wheel sets 70, 70 is substantially the same as the tread span of the

motor grader wheels

26 and 27, thereby facilitating the loading of'the attachment unit AU or AU on to a heavy duty transport trailer and the detachment of the motor grader therefrom when it is desired to transport the attachment unit a substantial distance.

The rear hopper wall 107 and. the hydraulically operated front hopper wall 108 discharge the material downwardly into a transversely extending feed channel 131 in the bottom of which travels a conveyor belt 132. Anchored along the front and rear side walls of the feed channel 131 are downwardly inclined deflecting plates 133, and secured to the undersides thereof are pliable sealing strips 134 composed of belting or rubber flashing material which establish sealing contact with the upper surface of'the conveyor belt 132. The deflecting plates 133 and the self-cleaning pliable sealing strips 134 are tapered in width or have their edges extending in diverging relation in the direction of travel of the belt, so that they are self-relieving of fil-l material as the material is carried toward the discharge end of the belt at the left hand side of the machine.

As shown in FIGURE 3, the right hand end of the corrveyor belt 132 passes around an adjustable idler roller 136 which is located at the right hand side of the machine. The shaft 137 of this idler roller is mounted at its ends in bearing blocks 138 which are capable of adjustable sliding travel along guideways 139. Adjusting screws 141 threading through yoke bars 142 effect sliding adjustment of the bearing blocks 133 for adjusting the tension on the conveyor belt 132. The top run of the belt carries a substantial part of the weight of the fill material in the hopper 105, and, accordingly, this top run is supported at Q closely spaced intervals by supporting rollersn144 carried 1' by the frame andextending fore and aft directly below fiho top'run of the belt. At its left hand end (FIGURE 7 a I 3) the conveyor belt passes around a driving roller 1 47 which is also pivotally mounted in slidabl e bearing blocks 149, whereby the axis of this driving roller 147 mayalso 7 belt.

through a speed reducer of approximately a 20 to 1 ratio with the driving pulley 147. The hydraulic motor 154 is'adapted to be driven from a hydraulic pump 157 which, in turn, is driven by a gasoline engine 158. One such hydrauliepump which has proven entirely satisfactory for the purpose is a well known gear pump having multiple pumping compartments. The internal combustion engine 158, hydraulic pump 157 and hydraulic motor 154 are extended in line along the rear edge of the machine, substantially entirely beneath the upwardly and rearwardly sloping rear hopper wall 107. However, in the use of certain designs of internal combustion engines, the projection of a part of the engine above the plane of this inclined rear hopper wall 107 may necessitate forming an upwardly bulged formation 107a in this rear hopper wall in the immediate vicinity ofthe engine.

The operator of the trench filling attachment unit AU sits on a transversely facing seat 161 which is located at the left hand side of the machine directly over the trench to be filled and immediately adjacent to the large discharge opening 162 in the hopper sidewall 106, through which the conveyor belt 132 discharges the fill material. The seat is mounted on a tubular bracket 163 projecting laterally from the side of the machine frame. Directly in front of the operators seat 161 are located controls 164166, one of which controls in a continuously or uniformly graduated manner the flow of hydraulic pressure to the hydraulic motor 154. Thus, it is possible for the operator to regulate with infinitely small speed changes the rate of discharge of the filling material from the discharge end of the conveyor belt 132 in order to take care of different depths and widths of fill and different operating conditions.

Referring to FIGURES 3 and 6, it will be seen that there is provided a plurality of spaced clean-out holes 167 in the vertical front and rear walls 131 of the feed channel. These clean-out holes afford access to both edge portions of the top run of the conveyor belt 132 that project outwardly beyond the sealing strips 134, and also to the top surface of the lower run of the belt. These clean-out holes are particularly useful for introducing live steam, furnace oil etc. for cleaning out encrustations of hot or cold asphaltic mix or other foreign matter; and also assist in discharging foreign matter in the normal running of the belt. To further aid in the cleaning of the conveyor belt 132, it will be seen from FIGURE 3 that the bottom return run of the belt is caused to pass upwardly over a centrally located idler roller 168, thereby aiding in the gravitational discharge of dirt and other foreign material from the bottom run of the belt. Still further, it will be seen from FIGURES 3 and. 8 that I have provided/a unique design of floating inside belt scraper 169 adjacent to the tail pulley 136. This inside belt scraper is of V-shaped outline comprising spaced bars 170a and'170b bent-to define sloping side wings 170, and having strips of pliable flashing material 170c clamped between the bars 179a and 17%. The lower edges of the pliable flashing material project below the bars for hearing against the top side of the return run of the belt, The V-shaped relationship of Wings 170 is pivotally connected at 171 to vertically swinging draft links 172 which are pivotally connected at their other ends to a pivot pin 173 carried by a stationary bracket 174 extending downwardly from the frame structure between the upper and lower runs of the The pivoted linkage support of the V-shaped scraper 169 enables itto have floating movement so that be ghifigd inwardly 0r Outward y the manipulation 0f it rides in directxgravitational contact against the top 'adjusting'screws" 151, to provide proper" belt alignment.

' The left hand driving roller 147 is driven through suitable driving gearing (notshown) from a hydraulic; motor 15 whichiispreferably-a 'vauetype of hydraulic motor. One such hydraulic motor which has proven'sab 7 isfactor'y for. the purpose isa relatively small high speed wane. motor, of well known make, which. is connected side. of the return run of the belt, before this returnrun passes under the tail 'pulley 137. It will'be'obvious that the V'-shaped deflecting wings 179 will deflect dirt and other foreign matter in an outward direction from the top side of the return run of the belt. The above described features of the clea'n-out'boles; sealing strips, V-shaped belt scraper, etc., are present in both attachment'unit embodiments AU and AU.

Referring now more particularly to the trench filling embodiment AU, and to the manner of effecting the strike-oif control of the material as it is discharged from the end of the conveyor belt down into the trench or shoulder area along the edge of the road, in one embodi ment of the invention this is effected by a strike-off box 175 which is detachably mounted on the left hand side of the machine for vertical adjusting movement. Referring particularly to FIGURES 4 and 5, the strike-off box 175 is a two-sided structure which can be pivotally raised and lowered by the operation of a double acting hydraulic ram 176 for effecting different levels of strike-off of the fill material. The box can also be varied in width for obtaining different widths of fill. The box comprises a back wall 177 and an outer wall 178 which are adapted to be swung up and down together by the hydraulic ram 176 around the pivot axis x of a rotatable extension tube 180 that telescopes within the front frame tube 65. As shown in FIGURE 4, the extension tube 180 has a plurality of spaced arcuate slots 181 in its top surface, into which is projected a retractable latching pin 182 which is slidably mounted in a boss 183 carried by the frame tube 65. The withdrawal of the locking pin 182 permits the extension tube 180 to be slid inwardly or outwardly within the frame tube 65 for bringing any desired one of the arcuate slots 181 into registering position to receive the latching pin 182, depending upon the desired strike-off width of the box 175. The arcuate formation of each of the slots 181 permits the slight rotative movement of the extension tube 180 within the frame tube 65, which occurs when the strike-off level of the box 175 is raised or lowered.

The outer wall 178 of the strike-off box comprises a triangular plate 185 having its apex welded or otherwise secured to the extension tube 180. This wall plate 185 is supplemented by an outer triangular wall plate 186 which is pivoted in reverse relationship to the inner wallplate 185. That is to say, the outer wall plate 186 has a rearwardly extending apex which is pivoted to the inner wall plate 185 adjacent to the rear edge of the latter on a transverse pivot pin 187. Formed in the outer wall plate 186 adjacent to its swinging front edge is a long arcuate slot 188, and passing through this slot and through the lower edge of the inner wall plate 185 is a clamping bolt 189 which serves to clamp the outer wall plate to the inner Wall plate in different angles of adjustment. A handle 191 secured to the upper portionof the outer wall plate 186 facilitates raising andlowering the outer wall plate 186 into these different angles of inclination, in which it is held by the clamping bolt 189. For example, when the strike-off box 175 is in a low position of adjustment for filling a deep trench T, as indicated in FIGURE 5, the outer Wall plate 186 is also adjusted into a lower position, with its bottom edge 186' extending substantially horizontal and parallel with the bottom of the trench T. On the other hand, when the machine is traveling along the road in transport condition, or is only filling a relatively shallow trench T, with the inner wall plate 185 tilted up to an elevated position, the outer wall plate 186 is then likewise tilted up to an elevated position with the clamping bolt 189 tightened in a lower portion of the arcuate slot 188, thereby insuring that both wall plates occupy an elevated position.

The rear wall 177 of the box is secured to the rear vertical edge of the triangular wall plate 186. As shown in FIGURE 2, this rear Wall 177 is made up of one or more vertically extending fabricated steel sections 177a, 177b, 1770, etc., which are adapted to be releasably secured together and to the triangular wall plate 185 by transverse bolts 193. The strike-off width of the box 175 can be increased or decreased by the addition or removal of successive rear wall sections 1770, 177d, etc.; and concurrently with the addition or removal of these sections the front extension tube 180 is shifted outwardly or inwardly to bring different arcuate notches 181 into registration with the latching pin 182. The lower front edge of each wall section 177a, 177b, etc. is faced with a reenforcing or wear resisting bar 194 (FIGURE 5). Projecting rearwardly from the back of one of the rear wall sections, such as the section 1770, is a pivot lug 195 carrying a pivot pin 196. Engaging over this pin is a clevis 197 at the lower end of the piston rod 198 of the double acting hydraulic ram 176. The cylinder 199 of this hydraulic ram has a clevis 201 at its upper end which is pivotally connected by pin 202 with a tongue 203 extending downwardly from the outer end of an overhead support tube 204. This support tube 204 extends horizontally across the top of the machine frame, where it passes through two spaced clamping brackets 285. Each of these clamping brackets has upwardly projecting yoke halves 206 which are adapted to be drawn together into rigid clamping engagement over the support tube 204 by the tightening of transverse clamping bolts 208. By releasing the clamping bolts 208, the support tube 204 can he slid inwardly or outwardly in order to maintain the double acting ram 199 substantially vertical as rear wall sections 177b177d, etc. are added or removed to vary the strike-off width of the strike-off box 175.

Bolted or otherwise secured to the inner side of the innermost wall section 177a is a vertical movable guide plate 211 (FIGURE 5) which extends substantially the height of the wall section and which has its front edge 212 curved in the form of an arcuate concave guide surface, and which has its rear edge 213 curved in the form of an arcuate convex guide surface, both of which curved guide surfaces have the pivotal center x of the extension tube 180 as their center of curvature. The front concave arcuate guide surface 212 has sliding guided engagement with a stationary convex arcuate guide surface 214 of corresponding radius formed along the back edge of a stationary vertical guide plate 215 which is secured to the adjacent side of the machine. This stationary guide plate 215 has its bottom horizontal edge 215 terminating substantially at the hinged trench and curb seal 217, which will be presently described. The matching engagement of the two arcuate guide surfaces 212-214 in the different raised and lowered positions of the strike-oif box prevents any of the fill material from working inwardly across the face of the rear wall 177 and discharging beyond the inner edge of this rear wall.

Referring now to the rear convex guide surface 213 on the guide plate 211, the strike-olf box 175 is laterally restrained against any inward or outward motion which would tend to laterally separate the arcuate guide surfaces 212-214, this lateral restraint being effected by the coaction between said rear convex guide surface 213 and a restraining roller 220 which rides on said guide surface (FIGURE 11). This restraining roller 220 has an outer annular flange 222 which overlaps the outer surface of the movable guide plate 211 along the convex rear guide surface 213. The restraining roller 220 is pivotally mounted on a pivot pin 223 projecting outwardly from a stationary mounting bar 224 which is secured to the frame of the machine directly on the inner side of the movable guide plate 211. This mounting bar 224 restrains inward shifting movement of the guide plate 211, and the outer confining flange 222 of the roller 220 restrains outward shifting movement of the movable guide plate 211, whereby inward or outward displacementof the strike-off box 175 is positively prevented. A reenforcing stationary strut bar 225 may extend between the mounting bar 224 and the machine frame.

Referring now to the hinged trench and curb seal 217, it will be seen from FIGURES 9 and 10 that this seal extends horizontally directly below the large discharge opening 162 through which the fill material is dischmged from the conveyor belt 132. This seal 217 comprises along hinge leaf 230 having hinge eyes 231 in alignment