Ground levelling trimmer

Abstract

A ground surface trimmer 10 has a bin 14 having an open front 22 and a scraper 20 extends across the front edge of the bottom 24 so as to scrape the ground surface and collect material through the front opening into the bin 14 . A main frame 12 has a towing hitch 13 for coupling to a tractor. Two rear wheels 31 are mounted behind the bin 14 and a ram 39 is used to adjust the height of the bin and scraper relative to the wheels. A first control 26 comprising a front closure 27 is operative to selectively control collection into the bin 14 through the front opening 22 of material scraped from the ground surface and the second control 40 comprising a movable pusher 43 within the bin is operative to selectively control the discharge from the bin 14 through the front opening 22 of material within the bin 14.

What I claim is:  
     
         1 . A ground levelling trimmer including: 
 (a) a bin which includes a front opening and an associated scraper, which, in use, is able to scrape the ground surface being trimmed when the ground levelling trimmer is moved in a forward direction such that material removed by the scraper from the ground surface is collected through the front opening into the bin;    (b) a mounting means having a wheel system including at least one ground engaging wheel and a frame by which the bin is mounted, the frame being mounted by the wheel system so as to allow selective elevational adjustment of the frame and of the bin mounted thereby relative to the wheel system so as to thereby enable selective adjustment of the height of the scraper relative to the ground surface; and    (c) a material holding control associated with the bin for selectively controlling at least one of the collection into the bin through the front opening of material scraped from the ground surface and the discharge from the bin through the front opening of material within the bin.    
     
     
         2 . A trimmer in accordance with  claim 1  wherein the material holding control is operative to selectively control both the collection into the bin through the front opening of material scraped from the ground surface and the discharge from the bin through the front opening of material within the bin.  
     
     
         3 . A trimmer in accordance with  claim 1  wherein the material holding control includes a selectively operable closure associated with the front opening of the bin, the closure being selectively movable between a closed position in which it substantially closes the front opening against collection of material scraped from the ground through the front opening into the bin and a range of open positions which provide differing proportions of the area of the front opening to be available for passage of material scraped from the ground surface through the front opening and into the bin.  
     
     
         4 . A trimmer in accordance with  claim 1  wherein the material holding control includes a material pusher located within the bin and which is selectively operable to push material within the bin forwardly so as to discharge material through the front opening of the bin.  
     
     
         5 . A trimmer in accordance with  claim 4 , wherein the material pusher is mounted in a rear of the bin, and is selectively controllable to swing forwards within the bin so as to push material in the bin forwardly towards the front opening.  
     
     
         6 . A trimmer in accordance with  claim 5 , wherein the material pusher is pivotally mounted at an internal upper portion of the bin so as to be movable in an arc to push material held in the bin towards the front opening.  
     
     
         7 . A trimmer in accordance with  claim 6 , in which the material pusher in vertical section has two planar parts angled obtusely internally of the bin so that the pusher is movable forwardly from a rear retracted position which minimally encroaches on the volume within the bin and so that the bottom edge transcribes the arc when moving forwardly through the bin.  
     
     
         8 . A trimmer in accordance with  claim 7 , wherein the internal bottom of the bin is arcuate in side view so that the bottom edge of the pusher follows this arcuate shape closely so as to allow effective movement of the majority of material in the bin by the pivotal forward movement of the pusher.  
     
     
         9 . A trimmer in accordance with  claim 4 , including a rearward extending frame mounted externally of the rear of the bin.  
     
     
         10 . A trimmer in accordance with  claim 9 , wherein a hydraulic ram is connected between the external rearward frame and the pusher to provide the required movement of the pusher within the bin.  
     
     
         11 . A trimmer in accordance with  claim 10 , wherein the ram extends into the bin in order to move the pusher and material in the bin towards the forward facing opening.  
     
     
         12 . A trimmer in accordance with  claim 1 , in which the bin has a shaped bottom having a front edge at which the scraper is located.  
     
     
         13 . A trimmer in accordance with  claim 12 , in which the scraper has a leading cutting edge defined by a leading face angled at about 45 degrees to a lower external bottom face which engages the ground surface so that an effective scraping or trimming occurs.  
     
     
         14 . A trimmer in accordance with  claim 1 , wherein a transverse roller is provided behind the said at least one ground engaging wheel for rolling along and thereby compressing the ground that has been scraped and levelled by the trimmer and for providing lateral stabilizing of the trimmer during use.  
     
     
         15 . A trimmer in accordance with  claim 14 , wherein the roller can be selectively moved from a ground engaging position to an elevated non-ground engaging position.  
     
     
         16 . A trimmer in accordance with  claim 1  in which the wheel system includes two spaced ground engaging wheels, which are within the lateral dimensions of the bin.  
     
     
         17 . A trimmer in accordance with  claim 1  wherein the mounting means includes a ram operative between the wheel system and a portion of the frame to enable selective height adjustment of the bin and associated scraper.  
     
     
         18 . A trimmer in accordance with  claim 3 , wherein said selectively operable closure comprises a front door which has a generally planar face which lies in the general plane of front opening and is selectively movable generally in that plane towards and away from the scraper to close and open the front opening.  
     
     
         19 . A trimmer in accordance with  claim 18  wherein said front door is mounted for pivoting movement about a pivot axis located inwardly of the bin behind the front opening.  
     
     
         20 . A trimmer in accordance with  claim 18  wherein a front door ram is operable between the frame of the trimmer and a link assembly coupled to the front door so as to selectively close and open the front opening.  
     
     
         21 . A trimmer in accordance with  claim 1  wherein the mounting means including the wheel system and frame do not extend laterally beyond the sides of the bin.  
     
     
         22 . A trimmer in accordance with  claim 1  wherein the scraper extends the entire width of the bin.  
     
     
         23 . A trimmer in accordance with  claim 1 , wherein a laser receiver is mounted to the trimmer to receive signals relating to the local ground level so as to thereby enable at least one of automatic height adjustment of the scraper and automatic control of the material holding control.  
     
     
         24 . A trimmer in accordance with  claim 1 , wherein ground engaging skis are provided on opposing sides of the trimmer, and having substantially co-extensive lower planar surfaces, such that the skis help stabilize the travel of the trimmer along the ground and protect the front lower corners of the bin.  
     
     
         25 . A trimmer in accordance with  claim 1  wherein the trimmer is towable behind a vehicle in use, the frame having a forwardly extending portion providing a coupling hitch for releasably coupling the trimmer to the vehicle and by which the front of the trimmer is supported above the ground.