Hydraulic lift assist for tractor towed earth moving apparatus

Abstract

The present invention includes hydraulic systems designed to allow the selection of a source of pressurized hydraulic fluid to lift a load. In one embodiment, a hydraulic system in accordance with the present invention comprises a hydraulic accumulator that may be selected as a source of pressurized hydraulic fluid to lift a load. Such a hydraulic system may or may not be part of a cushion ride system. The present invention also includes methods for selecting a source of pressurized hydraulic fluid to lift a load and earth moving or ground leveling apparatus that allow the selection of a source of pressurized hydraulic fluid to lift a load.

1 . A hydraulic system for lifting a load, comprising: 
 a hydraulic accumulator;    a hydraulic cylinder situated to lift a load upon actuation; and    one or more valves controlling the entry and exit of hydraulic fluid from the hydraulic accumulator, wherein at least one of the one or more valves is operatively disposed between the hydraulic accumulator and the hydraulic cylinder situated to lift a load and allowing for the non-selection of the accumulator as a source of hydraulic fluid to actuate the hydraulic cylinder situated to lift the load.    
   
   
       2 . The hydraulic system of  claim 1 , wherein the at least one of the one or more valves is an operator controlled valve.  
   
   
       3 . The hydraulic system of  claim 1 , wherein the at least one of the one or more valves is controlled by a sensor.  
   
   
       4 . The hydraulic system of  claim 3 , wherein the sensor is selected from the group consisting of a sensor for indicating the movement of the hydraulic cylinder situated to lift a load, a sensor for sensing the speed of a vehicle on which the apparatus is mounted, a sensor for sensing which gear a transmission of a prime mover is currently engaged, a sensor for sensing the engine speed of a prime mover, and a sensor for sensing the flow of hydraulic fluid to or from the hydraulic cylinder situated to lift a load.  
   
   
       5 . The hydraulic system of  claim 1 , further comprising a cushion ride system.  
   
   
       6 . The hydraulic system of  claim 5 , wherein the wherein the cushion ride system comprises a second hydraulic accumulator.  
   
   
       7 . The hydraulic system of  claim 1 , where the load comprises a bucket of an earth moving apparatus.  
   
   
       8 . The hydraulic system of  claim 1 , further comprising a source generating pressurizing hydraulic fluid in operative connection to the accumulator, the source located on a separate prime mover.  
   
   
       9 . An earth moving apparatus comprising: 
 a hydraulic accumulator;    a hydraulic cylinder situated to lift a frame of an earth moving apparatus, the hydraulic cylinder operatively connected to the hydraulic accumulator; and    a valve disposed between the hydraulic accumulator and the hydraulic cylinder for controlling the flow of hydraulic fluid from the hydraulic accumulator to the hydraulic cylinder situated to lift a frame of the earth moving apparatus.    
   
   
       10 . The earth moving apparatus of  claim 9 , wherein the earth moving apparatus comprises an earth moving scraper.  
   
   
       11 . The earth moving apparatus of  claim 9 , wherein the earth moving apparatus further comprises structures for operatively connecting to a source of pressurizing hydraulic fluid located on a separate prime mover.  
   
   
       12 . The earth moving apparatus of  claim 9 , wherein the valve is an operator controlled valve.  
   
   
       13 . The earth moving apparatus of  claim 9 , further comprising a sensor associated with the hydraulic system of the earth moving apparatus.  
   
   
       14 . The earth moving apparatus of  claim 13 , wherein the valve is controlled by the sensor.  
   
   
       15 . The earth moving apparatus of  claim 14 , wherein the sensor is selected from the group consisting of a sensor for indicating the movement of the hydraulic cylinder situated to lift a scraper frame, a sensor for sensing the speed of the earth moving apparatus, a sensor for sensing which gear a transmission of a prime mover is currently engaged, a sensor for sensing the engine speed of a prime mover, and a sensor for sensing the flow of hydraulic fluid to or from the hydraulic cylinder situated to lift a frame of the earth moving apparatus.  
   
   
       16 . The earth moving apparatus of  claim 9 , further comprising a cushion ride system.  
   
   
       17 . The earth moving apparatus of  claim 16 , wherein the wherein the cushion ride system comprises a second hydraulic accumulator.  
   
   
       18 . An improved earth moving or ground leveling apparatus having a frame with opposing sides, at least two ground engaging wheels supporting the frame, and a bucket with a floor and a pair of sidewalls, the improvement comprising: 
 a hydraulic accumulator;    a hydraulic cylinder situated to lift the bucket; and    one or more valves controlling the entry and exit of hydraulic fluid from the hydraulic accumulator, wherein at least one of the one or more valves is operatively disposed between the hydraulic accumulator and the hydraulic cylinder situated to lift the bucket and allowing for the non-selection of the accumulator as a source of hydraulic fluid to actuate the hydraulic cylinder situated to lift the bucket.    
   
   
       19 . The improved earth moving or ground leveling apparatus of  claim 18 , wherein the at least one of the one or more valves is an operator controlled valve.  
   
   
       20 . The improved earth moving or ground leveling apparatus of  claim 18 , wherein the at least one of the one or more valves is controlled by a sensor.  
   
   
       21 . The improved earth moving or ground leveling apparatus of  claim 20 , wherein the sensor is selected from the group consisting of a sensor for indicating the movement of the hydraulic cylinder situated to lift a scraper frame, a sensor for sensing the speed of the earth moving apparatus, a sensor for sensing which gear a transmission of a prime mover is currently engaged, a sensor for sensing the engine speed of a prime mover, and a sensor for sensing the flow of hydraulic fluid to or from a hydraulic cylinder of the earth moving or ground leveling apparatus.