CROSS-REFERENCE TO RELATED APPLICATION
This application claims the benefit of U.S. Provisional Patent Application 61/050,244 filed by the inventors herein on May 4, 2008, the disclosure of which is incorporated herein by reference.
The present invention relates to road vehicles used to repair and patch roadway surfaces, such as the filling of potholes or similar defects or concavities in asphalt-type pavements, and, more particularly, to roadway patching vehicles having a moveable boom mounted to their chassis for placement over the area to be patched and having a nozzle for dispensing various materials for implementing the patching function.
Various types of wheeled vehicles have been developed to patch roadway surfaces, particularly for the filling of potholes of various shapes and sizes. Some of these vehicles carry a load of hot patching-material in a vehicle-mounted hopper with a rear-mounted chute through which the patching material is dispensed into the pothole; typically, one more workman are required remove dust and loose material from the potholes and thereafter guide the patch material(s) into the pothole and tamp the surface of the patch material to conform to the surface of the roadway. More recent vehicles use a forward-mounted boom that is controlled by hydraulic actuators to position a nozzle over the pothole. The operator of the vehicle controls a flow of pressurized air directed into the pothole to removed excess water, dust, and loose debris with a further controlled flow of emulsified asphalt and/or a mix of emulsified asphalt/rock aggregate for delivery into and for filling of the pothole.
BRIEF DESCRIPTION OF THE DRAWING
A road patching vehicle for patching potholes of various sizes and shapes includes a boom assembly pivotally mounted at or on the front of the vehicle with a nozzle mounted at or toward the forward end of the boom. Various hoses connect the nozzle to at least a source of pressurized air, a source of patching emulsion (such as an asphalt emulsion), and a source of a rock aggregate with the vehicle operator controlling the flows individually or in various combinations thereof to prepare and then fill the pothole or other road defect to effect a patch. The nozzle is mounted on a pivot or journal to allow controlled pivoting or tilting of the nozzle under control of the operator in at least one degree of freedom. In a variant of the preferred form, the nozzle is mounted for control pivoting or tilting under the control of the operator in at least two degrees of freedom.
FIGS. 1 and 2 are respective opposite side views of a patching vehicle showing an adjustable boom at the forward end;
FIG. 3 is a perspective view of the vehicle shown in FIGS. 1 and 2;
FIG. 4 is a simplified schematic view of the patching materials flow system;
FIG. 5 is a first side view of the boom assembly including a rock aggregate transfer hose;
FIG. 6 is a second side view of the patching boom assembly, from the side opposite that shown in FIG. 5, in which the rock aggregate transfer hose and various components associated therewith have been removed for reasons of clarity;
FIG. 7 is a top view side view of the boom assembly of FIG. 6;
FIG. 7 a is a close-up view of the nozzle end of the boom of FIG. 7;
FIG. 8 is perspective of the nozzle assembly shown in FIG. 7 a;
FIG. 9 is a side elevational view of the nozzle assembly of FIG. 7 a with selected components omitted for reasons of clarity; and
FIG. 10 is a cross-sectional view of FIG. 9 showing the interior of the nozzle;
FIG. 11 a is a variant of the boom assembly in which the nozzle assembly is rotated ninety degrees from that shown in FIGS. 7-7 a;
FIG. 11 b is another variant of the boom assembly shown in FIGS. 7-7 a;
FIG. 12 is a another version of the nozzle mount having two degrees of freedom; and
FIG. 13 illustrates the manner in which the nozzle mount of FIG. 12 is controlled.
An exemplary road patcher vehicle with a nozzle system in accordance with one embodiment is shown in left-side and right-side views in FIGS. 1 and 2 and in an isometric perspective in FIG. 3 and is generally designated by the reference character 20; the overall road patcher configuration shown is representative of vehicles manufactured by Schwarze Industries, Inc. of Huntsville Ala. 35811 under the model RP-005 designation.
As shown in FIGS. 1-3, the truck-based road patcher 20 includes a boom assembly 22 at its forward end, an aggregate hopper 24 located rearwardly of the vehicle cab, and an asphalt emulsion holding tank 26 (dotted-line representation) at the rear of the vehicle. The boom assembly 22, which is preferably mounted toward or at the forward end of the truck chassis, is designed to pivot from a ‘stowed’ position in which the boom assembly 22 is parallel or near parallel to the front of the vehicle (and retained in a cradle 28) to and from a selected deployed position under control of a hydraulic cylinder 30. Another hydraulic cylinder 32 controls the angular relationship of distal end of the boom assembly 22 with the surface of the roadway and thus controls the distance between the distal end of the boom assembly 22 and the roadway (dotted-line representation). Thus, the remote end of the boom assembly can be moved through a path over the roadway under the control of the hydraulic cylinder 30 and the elevation at the end thereof above the roadway controlled by the hydraulic cylinder 32. The road patcher 20 includes a hydraulic pump/reservoir system (not specifically shown) for providing pressurized hydraulic fluid through various hoses and valves to various hydraulic cylinders, motors, actuators, etc. under the control of the vehicle operator, an electrical system for powering various actuators and related devices, and, additionally, an air compressor for supplying compressed air for various purposes.
The road patcher 20 includes a discharge nozzle 36, described more fully below, at the remote or forward end of the boom assembly 22 for discharging a flow of pressurized air, a flowable asphalt emulsion, and/or a mixture of the asphalt emulation and rock aggregate into or onto the roadway to effect patching. Various hoses, connectors, valves and the like connect to the nozzle 36 to the pressurized air source, the emulsified asphalt holding tank 26, and the aggregate hopper 24 of which only the aggregate transport hose 38 is shown in FIG. 1.
As shown in simplified schematic form in FIG. 4, the aggregate hopper 24 includes, in the preferred embodiment, a conveyor 40 for transporting aggregate to an aggregate feeder 42 into the rock transport hose 38. A forced-air blower 44, or similar device, provides a sufficiently high volume/velocity flow of pressurized air through an air supply hose or conduit 46 to move, entrain, and/or propel the aggregate along the interior of the rock transfer hose 38 to the nozzle 36 for discharge therefrom. The aggregate feeder 42 is preferably hydraulically driven and is designed to feed a measured or controlled amount of the rock aggregate into the rock aggregate transfer hose 38 to assure proper delivery of rock aggregate through the nozzle 36 to the pothole to be patched. For most applications, the rock aggregate is in the 0.25 to 0.375 inch range. The emulsion holding tank 26 contains a suitable emulsified asphalt and includes (not shown) an immersion-type heating element for maintaining the temperature of the emulsion. An air compressor 48 provides a flow of pressurized or compressed air through a compressed air line 50 to the emulsion tank 26 for pressurizing the emulsion tank 26 sufficiently to move the emulsion through a valve 52 into an insulated hose 54 to delivery to the nozzle 36 and discharge therefrom. The valve 52 is controllable to direct the flow of emulsion into the hose 54 or to cut-off the flow of emulsion and allow compressed air to flow directly into the hose 54 and to the nozzle 36. If desired, another separately controllable air line can be provided from the compressor 48 to the nozzle 36.
The system of FIG. 4 allows for the controlled discharge of pressurized air only from the nozzle 36, the discharge of the asphalt emulation from the tank 26 through the nozzle 36, and the discharge of the rock aggregate from the hopper 24, and the discharge of a mixture of the asphalt emulsion and the rock aggregate in a desired ratio from the nozzle 36. The mixing of the rock aggregate with the asphalt emulsion takes place within the nozzle 36 with the emulsion entering into the mixing space within the nozzle 36 through holes 36 a in the interior wall of the nozzle 36 (as shown in FIG. 10). In addition, a solvent-type cleaning system (not shown) can be used to purge and clear those components that are in contact the asphalt emulation, diesel fuel being a preferred solvent.
The boom assembly 22 is shown in side views in FIGS. 5 and 6 and in plan view in FIG. 7 and includes a mounting structure 56, typically formed as a weldment, that is attached to the forward end the vehicle. A boom 58 is attached at one end to the mounting structure 56 by a pivot 60 that allows the boom assembly 22 to move to and from a stowed position (in which the boom 58 is carried in the cradle 28) under the control of the hydraulic cylinder 30 and a selected deployed position (FIG. 1). Additionally, the boom 58 is connected through a second pivot 62 that allows the boom to tilt either in an upward direction or a downward direction relative to the ground surface under the control of the hydraulic cylinder 32 to control the distance between the outlet opening of the nozzle 36 and the pavement. The nozzle 36 is located at or adjacent the distal or remote end of the boom 58 with the rock aggregate transfer hose 38 (FIG. 5) coupled to the nozzle 36 and with the hose 38 attached to the boom 58 by a hose tower 64 and various restraining clips 66.
In the various figures, the boom assembly 22 is shown with its pivotable end mounted on the left or driver side of the vehicle; as can be appreciated, the organization of the boom assembly can be reversed, i.e., the pivotable end can be on the right or passenger side of the vehicle, or, if desired, the pivotable end of the boom assembly 22 can be mounted at some mid-position between the left and right sides of the vehicle. In the embodiment shown, only a single boom 58 is used; however, the use of at least one other boom pivotally connected to the end of the boom 58 (with an appropriate hydraulic control cylinder) to provide a two-boom assembly is not excluded.
The remote or distal end of the boom assembly 22 is shown in FIGS. 7, 7 a, and 8 and includes the nozzle 36 pivotally mounted on an axle 68 for limited tilting or pivoting motion about an axis 80 under the control of a bidirectional electrical actuator 70. As best shown in FIG. 7 a, the axis 80 is approximately parallel to the long axis of the boom 58. The actuator 70 is of the type having a ball-screw driven ram 72 that extends or retracts under the control of a drive motor 74. In the preferred embodiment, the actuator 70 is a 12 VDC linear actuator available from Warner Linear of Belvidere Ill. 61008 under the A-Track or the B-Track model designations. The remote end of the ram 72 is connected via a connecting rod 76 to a moment arm 78 and rotates the nozzle 36 about the axis 80 in response to the position of the ram 72. The rock aggregate transfer hose 38 (not shown in FIG. 7 a) connects to the inlet 82 of the nozzle 36. As shown in the detail of FIG. 7 a, various hose fittings (represented at 84) and electrically controlled proportioning valves 86 connect to the nozzle 36 for receiving the emulsion and compressed air lines (not shown in FIG. 7 a) and regulating the flows thereof into the nozzle 36. The emulsion is introduced into the main nozzle passageway via interior openings 36 a as shown in FIG. 10 as discussed below.
FIGS. 9 and 10 illustrate the range of angular motion of the nozzle 36 under the control of the ram 70 and a representative joystick-type controller 88 in which movement of the joystick J causes corresponding pivoting of the nozzle 36. As shown in FIG. 9, the nozzle 36 is pivoted counterclockwise when the ram 72 is retracted and, conversely, pivoted clockwise when the ram 72 is extended. A suitable joy-stick controller is available from SureGrip Controls, Inc., Kamloops, B.C., Canada under the JL-series designation.
The pivotally or tiltable nozzle mount provides enhance functionality to the road patcher vehicle. More specifically and after the vehicle operator deploys the boom 58 to position the distal end over the pothole or area to be patched, the operator directs a flow of pressurized air (from the rock aggregate blower 44, FIG. 4) to eject dust, dirt, debris, standing water, etc. from the pothole or area to be patched. Depending upon the nature of the area to be patched, the operator can pivot or tilt the nozzle 36 through some or all of its range of motion to provide a more thorough air “blast” cleaning. Thereafter, a controlled amount of the liquid asphalt emulsion is directed onto or into the area to be patched to function as a “tack” layer. The operator can pivot or tilt the nozzle 36 through some or all of its range of motion to assure complete coverage, and, if desired, also move the boom 58 under the control of the hydraulic cylinder 30 (FIG. 7), to assure a seamless patch particularly along the edges of the patch. Thereafter, a mix of the rock aggregate and the liquid emulsion is blown into the patch area with the high velocity air flow functioning to ‘compact’ the mix from the bottom upward to the surface of the roadway. Lastly, a thin layer of a dry rock aggregate (i.e., without the liquid asphalt emulation) is deposited onto the patch. As in the case of the first two steps, the operator can pivot or tilt the nozzle 36 through some or all of its range of motion during the second two steps to assure proper placement of the patching materials and, if desired, also move the boom 58 as desired.
In the embodiment described above, the axis 80 about which the nozzle 36 is pivoted or tilted is substantially parallel to the long axis of the boom 58 but displaced therefrom (as shown in FIG. 7 a). Thus, in those cases were the boom 58 is fully extended so that its axis is parallel to the long axis of the vehicle, the nozzle 36 can sweep a path back and forth along the lateral or side-to-side direction. Thus, as the vehicle moves along the roadway, the nozzle 36 can be moved side-to-side as needed to provide the filling of the pothole or the repair of the damaged area. In some cases and as shown in FIG. 11 a, the nozzle 38 can be mounted so that the pivoting or tilting axis 80 is approximately perpendicular to the long axis of the boom 58.
A variation of the embodiment shown in FIG. 11 a is shown in FIG. 11 b in which two degrees of freedom are provided. As shown, the boom 58 is modified to provide a bearing mounted rotatable connection between the boom 58 and the nozzle assembly with a gearmotor 82 providing controlled rotation of the nozzle assembly about axis 84. The gearmotor 82 include a reversible electric drive motor with a gear reduction head (or other suitable transmission) and a shaft 86 connected to the nozzle assembly to effect limited rotation about the axis 84. As in the case of the embodiment described above, a dual-axis joystick can be used to provide control inputs.
FIGS. 12 and 13 illustrate an omni-directional mount for the nozzle 36 such that two degrees of pivoting or tilting are possible. As shown in the cross-sectional view of FIG. 12, the nozzle 36 is mounted in a spheroid mount that includes a rotor member 90 having a surface of revolution 92 that is a partial sphere. The rotor member 90 is carried in a stator 94 having a mating surface with sufficient clearance that the rotor member 90 and the nozzle 36 an pivot or tilt from the vertical. As shown in FIG. 13, a connecting plate 96 is mounted to the nozzle 36 at its upper end and includes and appropriate number of connecting rod ends 98 that connects to an appropriate pull and/or push actuator, such as the linear electric actuator 70 described above or a fluidic (hydraulic or pneumatic) actuator (not shown). Conventional joystick controllers 100 are used to individually control the two actuators shown; in the alternative, a single joystick type controller with a 360° range that provides appropriately resolved signals to the actuators can be used. The rod ends 98 are of the type (i.e., ball ends) that allow of angular movement so that to accommodate the tilting of the nozzle 36.
As will be apparent to those skilled in the art, various changes and modifications may be made to the illustrated embodiment of the present invention without departing from the spirit and scope of the invention as determined in the appended claims and their legal equivalent.