Abstract:
A road patching vehicle for patching damaged areas or potholes of various sizes and shapes on a roadway includes a boom assembly pivotally mounted at or on the forward end of the vehicle with a nozzle mounted at or toward the forward end of the boom. Various hoses connect the nozzle to 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.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    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. 
     
    
     BACKGROUND 
       [0002]    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. 
         [0003]    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. 
       SUMMARY 
       [0004]    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. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
         [0005]      FIGS. 1 and 2  are respective opposite side views of a patching vehicle showing an adjustable boom at the forward end; 
           [0006]      FIG. 3  is a perspective view of the vehicle shown in  FIGS. 1 and 2 ; 
           [0007]      FIG. 4  is a simplified schematic view of the patching materials flow system; 
           [0008]      FIG. 5  is a first side view of the boom assembly including a rock aggregate transfer hose; 
           [0009]      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; 
           [0010]      FIG. 7  is a top view side view of the boom assembly of  FIG. 6 ; 
           [0011]      FIG. 7   a  is a close-up view of the nozzle end of the boom of  FIG. 7 ; 
           [0012]      FIG. 8  is perspective of the nozzle assembly shown in  FIG. 7   a;    
           [0013]      FIG. 9  is a side elevational view of the nozzle assembly of  FIG. 7   a  with selected components omitted for reasons of clarity; and 
           [0014]      FIG. 10  is a cross-sectional view of  FIG. 9  showing the interior of the nozzle; 
           [0015]      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;    
           [0016]      FIG. 11   b  is another variant of the boom assembly shown in  FIGS. 7-7   a;    
           [0017]      FIG. 12  is a another version of the nozzle mount having two degrees of freedom; and 
           [0018]      FIG. 13  illustrates the manner in which the nozzle mount of  FIG. 12  is controlled. 
       
    
    
     DESCRIPTION 
       [0019]    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. 
         [0020]    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. 
         [0021]    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 . 
         [0022]    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 . 
         [0023]    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. 
         [0024]    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 . 
         [0025]    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. 
         [0026]    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. 
         [0027]      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. 
         [0028]    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. 
         [0029]    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 . 
         [0030]    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. 
         [0031]      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 . 
         [0032]    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.