US 3909146 A
A paving machine for spreading paving materials onto a road surface to be paved as the machine is advanced thereover, includes a wheeled frame, a hopper for receiving paving materials mounted on the frame, and a chute through which paving materials are discharged onto the paving surface. The hopper includes a base on which the paving materials are deposited, and the base is reciprocated below an abutment to cause the paving materials to be swept by the abutment from the base into the chute.
Description (OCR text may contain errors)
United States Patent Hoffman [4 1 Sept. 30, 1975 l 54 l PAVING MACHINE  Inventor: Richard C. Hoffman, Agincourt,
Canada  Assignee: Allatt Limited, Downsvicw, Canada  Filed: Sept. 23, 1974  Appl. No.: 508,399
 U.S. Cl. 404/110; 298/17 R  Int. Cl. ..E01C 19/18  Field of Search 404/110, 108, 106, 84,
 References Cited UNITED STATES PATENTS 1,974,013 9/1934 Clausen 404/106 2,479,800 8/1949 Williams 404'/l 10 3.208360 9/1965 Hayes 404/110 Frantz 404/1 10 X Pollitz 404/84 Prinmry ExaminerNile C. Byers, Jr. Attorney, Agent, or Firm-Leon Arthurs 5 7 ABSTRACT A paving machine for spreading paving materials onto a road surface to be paved as the machine is advanced thcreover, includes a wheeled frame, a hopper for receiving paving materials mounted on the frame, and a chute through which paving materials are discharged onto the paving surface. The hopper includes a base on which the paving materials are deposited, and the base is reciprocated below an abutment to cause the paving materials to be swept by the abutment from the base into the chute.
11 Claims, 9 Drawing Figures US. Patent Sept. 30,1975 Sheet 1 of 3 3,909,146
US. Patent Sept. 30,1975 Sheet 2 of3 3,909,146
US. Patent Sept. 30,1975 Sheet 3 01 3 3,909,146
PAVING MACHINE This invention relates to machines for paving road T surfaces with paving materials, such as bituminous materials, for example.
A known kind of paving machine includes a wheeled frame with a hopper at one of its ends which receives supplies of bituminous materials from a truck; a chute adjacent the opposite end through which materials are discharged onto the surface to be paved, and a conveyor which conveys the materials from the hopper to the chute. The machine to which the present invention relates is of this type and is compact enought to enable paving to be satisfactorily carried out in small, restricted areas, such as driveways, for example.
In a machine of this nature, the hopper generally has i a relatively small capacity, and on larger jobs, requires to be refilled from time to time while the paving is in progress. Further paving materials are accordingly supplied to the hopper by a supply truck of much larger capacity than the hopper; the supply truck usually being coupled to the paving machine to enable continuous replenishment of the hopper to be carried out while the paving machine is in operation.
With some materials, such as bituminous materials, whichhave high viscosity, it is generally required that the materials be in a heated condition during the paving operation, and the materials are accordingly supplied from the supply truck in the required heated condition. It is resultantly important that the paving materials in the hopper be conveyed expeditiously to the chute of the machine, so that the materials can be spread and leveled on the paving surface while they are still warm.
It is therefore an object of the invention to provide an improved paving machine of the described type for use in small or restricted areas. Specifically, the inven-.
tion seeks to provide such paving machines with improved means for conveying the paving materials from the hopper at one end to the chute near the other end of the machine.
According to the invention, the hopper includes a base on which the paving materials are piled and which is reciprocable towards and away from the chute; means effective upon reciprocation of the base being provided to procur sweeping of the paving materials rocation of the base has the prelininary effect of advancing its pile of paving materials towards the chute, thereby creating a gap between the pile and the abutment; the gap being then filled by fresh materials from the supply truck. Thus, when the base is retracted to complete a reciprocatory cycle, the abutment sweeps the materials along the base so that some drops into the chute. Continued reciprocation of the chute thereby causes a continued supply of paving materials to be swept from the base into the chute and there through to the spreading and levelling means.
The reciprocating means may include a fluidoperated motor of the expansion-contraction type, such as the familiar piston-cylinder combination, disposed beneath the base and connected between the base and the frame.
One embodiment of the invention inccorporating these and other features of the invention, will now be described, by way of example only, with reference to the accompanying drawings, of which, 3
FIG. 1 is a side view of a paving machine, the rear portion of a supply truck also being shown,
FIG. 2 is a plan view, partly broken away, of the pav' ing machine, I
FIG, 3 is a sectional view, partly broken away, of the paving machine, taken along the line 33 of 2, with the hopper base being in retracted position and with an initial supply of bituminous materials in the hopper,
FIG. 4 is a similar view to FIG. 3, but showing the base in a forward position, with further bituminous materials being supplied from a truck,
FIG. is a similar viewto FIG. 4, but showing the base in a retracted position, with bituminous material flowing down the chute,
FIG. 6 is an end view of the machine, partly in section, and with certain parts omitted for clarity, showing the side walls of the hopper in a laterally outermost position,
FIG. 7 is a sectional view through the hopper portion of the machine, taken along line 77 of FIG. 2, showing the. side walls of the hopper moved to a laterally closer position,
FIG. 8 is a rear view showing the hopper in its upwardly tilted position with side walls in the position shown in FIG. 7, and
FIG. 9 is a side view, partly in section, showing the hopper in its upward tilted position.
Referring to the drawings, a paving machine has a main frame 10 mounted on forward and rear pairs of road wheels 12. The main frame 10 carries a hopper 14 for paving materials, such as bituminous materials, and the hopper 14 includes a hopper frame 16 which is pivotally mounted on the main frame 10 for pivotal movement about a transverse axis between level and upwardly tilted positions. A pair of double-acting, hydraulic, piston and cylinderjacks 18 are pivotally connected between the main frame 10 and hopper frame 16 to effect the pivotal movement of the hopper (see FIGS. 8 and 9).
A chute 20 extends in a downwardly inclined manner from one end of the hopper through which the materials are fed from the hopper 14 to a spreader 22. The
, spreader 22 is a transversely-extending rotatable helical roll mounted on the main frame 10, and feeds paving materials from the chute 20 to a surface to be paved. A vertically adjustable screed 24 is also mounted on the frame, for levelling the paving material on' the paving surface after it has been spread thereon by the spreader 22. Also, two feed gates 26 are mounted side by side at the entrance to the chute 20,
and are moveable between open and shut positions to control the flow of the paving materials discharged through the chute 20. The gates 26 are actuated by a pair of hydraulic jacks 28 connected between the main frame 10 and the gates 26.
The hopper 12 has a base plate 30 which, in this em bodiment, forms the floor of the hopper, and is slidably mounted on the hopper frame 16 for reciprocating motion towards and away from the chute 20; the reciprocating motion being effected by a hydraulic jack 32 connected between the hopper frame 16 and the base plate 30. The hopper 14 also has abutment 34 secured to and extending transversely across the hopper frame 16 adjacent the end of the base plate 30 remote from the chute 20. The abutment 34 has a vertical surface 36 immediately adjacent to the upper surface of the base plate 30 which it overlaps and is perpendicular thereto. It is noteworthy that the abutment 34 always overlaps base 30 although it is removable for cleaning purposes.
The hopper 14 has opposed side wings 38 which are pivotally mounted on the hopper frame 16 for pivotal movement towards and away from one another about axes parallel to the path of reciprocation of the base plate 30. Each wing 38 has an angled section with a first side wall 40 extending from the hopper frame 16 and a second side wall 42 extending perpendicularly from the end of the first side wall 40 remote from the hopper frame 16. Pivotal movement of the hopper wings 38 is effected by hydraulic jacks 43 connected between the hopper frame 16 and the first side walls 40;
In the use of the machine, paving materials are supplied from a dump or supply truck 44 with a tip-up body 46 having a tailgate 48 pivotally mounted at its upperend on the body 46. The truck 44 and paving machine are coupled together by suitable coupling rods 51, for example, connected between the main frame and the rear axle of the truck 44, the coupling rods 50 being adjustable in length to enable the truck 44 and paving machine to be correctly positioned relative to one another.
The hopper 14 is initially in a level position, with the hydraulic jack 18 retracted, the side walls 42 being in their laterally outermost position, with the hydraulic jacks 43 also retracted, Further, the chute gates 26 are initially in the closed position, with the hydraulic jack 7 28 extended, and the hopper base plate 30 is in its position nearest the chute 20, with the hydraulic jack 32 contracted.
The various hydraulicjacks are connected to suitable manually operated controls and a hydraulic pump. Also, the spreader 22 and the road wheels 12 are driven by hydraulic motors connected to the hydraulic pump driven by an internal combustion engine, for example. The hydraulic pump and motors and the engine are mounted on the main frame 10. The nature of the hydraulic system will be clear to the man skilled in the art, and thus it is not believed necessary to describe the system in any more detail.
Suitable paving materials 50 are tipped into the hopper 14 from the truck 46, and pile on the base plate 30, the abutment 34, and the first sidewalls 40 which are in a horizontal position. The base plate 30 is then reciprocated to and fro, by operation of the hydraulic jack 32. As the base plate 30 moves towards the abut ment 34 and passes beneath its vertical surface 36, paving materials 50 on the base plate 30 are engaged by the vertical abutment surface 36 and swept or pushed forwardly on the base plate 30. Subsequent movement of the base plate 30 in the opposite direction carries the materials with it towards the chute 20, While further paving materials pour from supply truck 46 onto the base plate 30 adjacent the abutment 34, as the base plate 30 and its load move away from the abutment 34.
As the base plate 30 continues to reciprocate, the interaction of the vertical abutment surface 36 and the supply of further paving materials 50 from the truck 46 causes paving materials to be pushed off the end of the base plate 30 into the chute 20.
The gates 26 are opened by operation of the jacks 28, so that the paving materials fall into the spreader 22 and are spread by its helical action onto the surface to be paved, the screed 24 having previously been set to a desired height. The coupled truck 46 and paving machine are moved forwardly at a suitable rate, powered by the hydraulic drive to the wheels 12 of the paving machine: the reciprocation of the base plate 30 being continued to maintain the supply of paving materials to the chute 20.
The supply of paving materials to the paving surface can be controlled by adjusting the position of the gates 26 by means of the jacks 28 to vary the effective inlet area of the chute 20.
At an appropriate time preferably before paving is finished for the time being,the truck 46 is uncoupled,
from the paving machine and driven away. With reciprocation of the base plate 30 continuing, the hopper 14 is pivoted to an upwardly tilted position, by extension of the jack 18, to incline the base plate 30 downwardly towards the chute 20, thereby assisting the feed of paving machine from the base plate 30 to the chute 20. Also, the hopper wings 38 are moved to their laterally inner positions, by extending the jacks 43, so that the i first side walls 40 therefore become downwardly inclined, with the paving materials thereon flowing downwardly to the base plate 30. Thus, the hopper 30 can be substantially emptied when desired, it then being a relatively easy matter to scrape out any remaining material. Also, the abutment 34 can be removed for cleaning purposes. Since the abutment 34 is very close to the base plate 30, it is unlikely that any significant amount of paving materials will be moved beneath and beyond the abutment vertical surface 36, during movement of the base 30 towards the abutment 36, thereby minimising the likelihood of paving materials causing jamming of the base plate 30in the region of the abutment 34.
What I claim is:
1. A paving machine for spreading paving materials onto a road surface to be paved asthe machine is advanced thereover, said machine including a wheeled frame, a hopper for receiving paving materials mounted on the frame, a chute at one end of said 2. A paving machine according to claim 1 whereon the sweeping means comprises an abutment extending upwardly above the base transversely of the path of re ciprocation thereof, and the reciprocating means causes paving materials on the base to move towards and into the feed chute by engagement of the paving materials against the abutment when the base moves in the direction of the abutment, and by the flow of further paving materials onto the base when the base moves in the opposite direction.
3. A paving machine according to claim 2 wherein the abutment is located immediately adjacent the base.
4. A paving machine according to claim 2 wherein the abutment constitutes the hopper bottom.
5. A paving machine according to claim 2 wherein the abutment is removable for cleaning purposes.
6. A paving machine according to claim 1 wherein the reciprocating means includes a fluid-operated motor beneath the base and connected between the base and the frame.
7. A paving machine according to claim I wherein the hopper is pivotably mounted on the frame for piv otal movement about a transverse axis adjacent the feed chute, so that the hopper can be tilted to assist the passage of paving material into the chute.
8. A paving machine according to claim 1 wherein the hopper has opposed pivotally mounted side walls which are pivotable relatively towards and away from each other about axes parallel to the path of reciprocation of the base, whereby relative movement of the side walls away from one another increases the storage capacity of the hopper and relative movement towards one another urges the material onto the base.
9. A paving machine according to claim 1 wherein the frame carries a transversely extending rotatable spreader roll adjacent a lower end of the chute to spread paving material from the chute onto the surface to be paved.
10. A paving machine according to claim 1 wherein a feed gate is mounted in the chute, the gate being adjustable to vary the effective flow area of the chute.
11. A paving machine according to claim 10 wherein the frame carries a vertically adjustable screed extending transversely of the frame adjacent the spreader to level the paving material on the surface to be paved after the material has been spread thereon by the