Asphaltic pavement treating apparatus and method

In apparatus for treating asphaltic pavement for road surfacing and the like, a combination comprising:

• first means for converting old asphaltic pavement into a loose, heated aggregate-asphalt mixture that has the consistency of approximately the original aggregate size range while moving along the ground surface and while the mixture remains on the ground surface;
• means trailing said first means for picking up said mixture from the ground surface;
• means movable with said picking-up means for for adding a preselected amount of conditioner for old asphaltic pavement to said picked-up mixture, said conditioner replacing at least some of the ingredients lost during oxidation of the old asphaltic pavement and softening said pavement;
• and
• means movable with said adding means for thoroughly and intimately mixing the conditioner and picked-up mixture independently of the ground surface while confined in a mixing chamber supported above the ground surface, said chamber having a bottom wall over which the conditioned mixture is moved above the ground surface between an inlet and an outlet and further having paddle blades disposed in an axially spaced and radially extending arrangement above the bottom wall between the inlet and outlet, to form a reconditioned mixture of a composition and consistency suitable for being rolled into a new mat of asphaltic pavement while moving relative to the ground surface,
• said converting, picking up and mixing being coordinated in movement with one another another relative to the ground surface.

In a method of treating asphaltic pavement for road surfacing and the like, the steps comprising:

• converting old asphaltic pavement on a ground surface into a loose, aggregate-asphalt mixture by heating said pavement to a selected temperature and depth and reducing the size thereof to approximately the original aggregate size range while said pavement and mixture remains on the ground surface and while moving relative to the ground surface;
• picking up said mixture from the ground surface and simultaneously mixing by a tumbling action and heating said picked-up mixture to a temperature suitable for adding a conditioner and for being rolled into a new mat of asphaltic pavement while moving relative to the ground surface;
• adding a preselected amount of conditioner for old asphaltic pavement to said picked-up mixture, said conditioner replacing at least some of the ingredients lost during oxidation of the old asphaltic pavement and softening said pavement;
• thoroughly and intimately mixing the conditioner and picked-up mixture independently of the ground surface while confined in a mixing chamber supported above the ground surface, said chamber having a bottom wall over which the conditioned mixture is moved above the ground surface between an inlet and an outlet and further having paddle blades disposed in an axially spaced and radially extending arrangement above the bottom wall between the inlet and outlet, to form a reconditioned mixture of a composition and consistency suitable for being rolled into a new mat of asphaltic pavement while moving relative to the ground surface,
• said converting, picking up, heating and mixing being coordinated in movement with one another relative to the ground surface.

In a method of treating asphaltic pavement for road surfacing and the like, the steps comprising:

• converting old asphaltic pavement on a ground surface into a loose, heated, aggregate-asphalt mixture by heating said pavement to a selected temperature and depth and reducing the size thereof to approximately the original aggregate size range while said pavement and mixture remains on the ground surface and while moving relative to the ground surface;
• picking up said mixture from the ground surface while moving relative to the ground surface;
• adding a preselected amount of conditioner for old asphaltic pavement to said picked-up mixture, said conditioner replacing at least some of the ingredients lost during oxidation of the old asphaltic pavement and softening said pavement;
• and
• thoroughly and imtimately mixing the conditioner and picked-up mixture independently of the ground surface while confined in a mixing chamber supported above the ground surface, said chamber having a bottom wall over which the conditioned mixture is moved above the ground surface between an inlet and an outlet and further having paddle blades disposed in an axially spaced and radially extending arrangement above the bottom wall between the inlet and outlet, to form a reconditioned mixture of a composition and consistency suitable for being rolled into a new mat of asphaltic pavement while moving relative to the ground surface,
• said converting, picking up and mixing being coordinated in movement with one another relative to the ground surface.

In apparatus for reconditioning asphaltic pavement for road surfacing and the like, a combination comprising:

• a frame supported on wheels for vehicular movement over a ground surface;
• an elongated, generally cylindrical housing on said frame mounted for rotation about a longitudinal axis forming an inner chamber elevated above the ground surface having a material inlet at one end and a material outlet at the opposite end through which a loose asphalt-aggregate mixture delivered to said material inlet passes and is discharged through said material outlet, said chamber having a gas inlet at one end and a gas outlet opposite the gas inlet to pass gas through said chamber;
• drive means operatively associated with said housing for rotating said housing about its longitudinal axis;
• heating means operatively associated with said housing for heating gases passed through said gas inlet in heat exchange relation to said mixture and out said gas outlet to heat said mixture as said mixture is tumbled in said housing for uniformly, simultaneously heating and mixing said mixture;
• means movable with said heating means and operatively associated with said housing for adding a conditioner replacing at least some of the ingredients lost by oxidation of the asphaltic pavement to said heated mixture;
• and
• mixing apparatus on said frame for uniformly mixing said heated, conditioned mixture,
• said housing having a plurality of circumferentially spaced inlet openings on the periphery thereof adjacent the front end, each having a scoop arranged to direct said mixture into the inside of the housing upon the rotation thereof from a feed trough.