Abstract:
A bark dust unloading system has a mechanism for moving material in a container to an opening at the rear of the container. An auger assembly in combination with rotating rake assemblies move the material from the sides of the container to the opening. A blower assembly provides an air stream to transport the material deposited in the opening through a hose. The hose is used to distribute the material. An automatic control controls the operation of the unloading system including the movement of the material, the blower system, the augers and rake assemblies. A remote control allows the operator to alter the operations while directing placement of the bark dust. This provides for operation by a single operator.

Description:
This is a continuation-in-part of Patent Application titled BARK DUST UNLOADING SYSTEM, U.S. Ser. No. 09/438,472, filed Nov. 11, 1999 now U.S. Pat. No. 6,131,830. 
    
    
     FIELD OF THE INVENTION 
     This invention relates to the unloading and distribution of material, e.g., used as ground cover and including bark chips, mulch and the like, from a container, e.g., a truck box, from which the material is fed to a blower which projects the material through a hose, the distal end of which is manipulated to controllably direct the material over a ground cover area. More particularly, it relates to the manner of feeding the material from the container into the distribution apparatus. 
     BACKGROUND OF THE INVENTION 
     The use of bark dust and chips, mulch and other material as ground cover is common and is hereafter sometimes collectively referred to as bark dust or chips. Such materials are purchased by the truck load and spread under trees, around bushes and so on. A method of distribution has been developed wherein a blower system is installed on the back of a bark hauling truck. A feeder bin at the back end overlies a blower tube to which a flexible hose is attached. The bark dust/chips are pushed into the feeder bin and then fed into the air stream of the tube and into and through the hose. An operator directs the distal end of the hose for depositing the material into the desired area. The hose is sufficiently long to enable such distribution of the bark dust/chips substantial distances from the truck, e.g., into a back yard of a residence with the truck sitting in a driveway at the front of the house. 
     In the prior art, it takes two operators to handle this process. One operator manipulates the discharging end of the hose. The other operator oversees the process of depositing the bark chips into the feeder bin at the end of the truck box. A moving front wall is used to push the material toward the back of the truck box/container but operation of the wall needs to be monitored and controlled as well as monitoring of the material flow into and through the feeder bin, e.g., to unplug the feeder bin inlet should clumps of the material bridge over the inlet and close off flow into the feeder bin. 
     BRIEF DESCRIPTION OF THE INVENTION 
     It is an object of the present invention to obviate the need for the second operator (monitoring flow of the material into the feeder bin). To accomplish this objective, the process of feeding material into the feeder bin needs to be automatic and should anticipate and correct the common problems of feeding too fast or too slow and bridging of the materials across the feeder bin inlet. 
     In the preferred embodiment, the bridging problem is satisfied by enlarging the opening into the feeder bin and providing a double screw or auger inlet feed for directing flow into the feeder bin. The double screws or auger provide the function of moving material from the sides of the box to the opening into the feeder bin and they cooperatively break up and force material through the system that heretofore caused bridging. This feature will be more clearly understood upon reference to the detailed description. 
     Controlled feeding is achieved by automating the movement or feeding of the material from the front to the rear of the container, e.g., in response to a detection mechanism or control. In the preferred embodiment, the detection mechanism is a pressure sensing device that senses resistance to movement of the material. Through trial and error as concerns the different materials being distributed, it is known what pressures are too low so as to require the movement to commence and what pressures are too high so as to require the pushing movement to stop for optimum feeding of material into and through the feeder bin. These pressures are entered into a control that starts and stops the movement of material accordingly. 
     The feeding process from the front to the rear of the truck is preferably accomplished by a moving front wall or alternatively a moving floor, either one or a combination thereof being responsive to the above-mentioned detection mechanism. 
     The sole operator also has adjustability capabilities so that if he is experiencing too fast or too slow feeding, he can adjust the pressure settings. There are many variations of such controls even as relates to a pressure control as briefly described. Again, such will become apparent upon reference to the following detailed description and drawings referred to therein. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a view of a bark unloading system of the present invention; 
     FIG. 2 is a view of a remote control for controlling the bark distribution system of FIG. 1; 
     FIGS. 3-5 are schematic views illustrating the movement of materials through the system of FIG. 1 utilizing a moving front wall; and 
     FIGS. 6,  7 ,  8 A and  8 B illustrate the movement of materials, front to back, utilizing a moving floor. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIG. 1 illustrates a bark dust unloading system of the present invention. The system includes a mobile container  12  and in this embodiment the container  12  is a box mounted to the chassis of a vehicle such as a truck  14 . The container  12  includes a distribution system that will unload and distribute material such as bark dust that is contained within the container  12 . Basically a movable wall  16  is provided to move the material toward an open feeder bin  18 . A known rotating baffle gate  19  is provided in the feeder bin  18  and moves the material through the feeder bin. The feeder bin  18  is coupled to an air conduit  21  which directs air flow from a blower system  20 . The air flow transports the material received from the feeder bin  18  outwardly through a hose  22 . The movable wall  16  is movable in the container  12  toward and away from the feeder bin  18  by a cylinder  24 . An auger assembly  30  (double screw-type augers) is mounted on the rear door (end gate  32 ). The auger assembly  30  is arranged to move the material from the sides of the container  12  toward the open feeder bin  18 . Mounted above the auger assembly  30  on the end gate  32  are multiple rotatable rake assemblies  34 . The rake assemblies  34  loosens and directs the bark dust downwardly toward the auger assembly as the movable wall moves the material into the rake assemblies. 
     Motive power is provided to the components of the container  12  by a hydraulic pump  40  that is coupled to the transmission of the vehicle  14 . A hydraulic reservoir  42  is mounted at the forward end of the container  12  in front of the movable wall  16 . The blower assembly  20  and the hydraulic cylinder  24  are also mounted in the forward portion of the container  12 . 
     A drive motor  52  drives the augers  30  and the rake assemblies  34 . The rotating baffle  19  of the feeder bin  18  is rotatably driven by a drive motor  54 . 
     A pressure sensing device  56  is coupled to the cylinder  24 . The pressure sensing device  56  is adjustable by a control  58 . The pressure applied against the wall  16  may thus be adjusted by the control  58  to vary the pressure applied by the wall against the material. The different materials received in the container will vary in their resistance to such movement and will require different pressure settings to properly direct the movement of the wall  16  and thus the rate at which material is delivered to the feeder bin  18 . 
     A remote control  60  is also provided to control the operation of the bark dust unloading system. The remote control  60  has a switch  62  for controlling the speed of the blower to thus control the flow of the air through the open feeder bin  18  and the hose  22 . Another switch  64  is provided to control the rotational speed of the rotating baffle  19  of the feeder bin  18 . A switch  66  is provided as a pause and resume control that pauses the entire system. Switch  68  is an auxiliary switch in the control  60  and could, for example, be provided to operate the pressure control unit  58  to vary the pressure applied to the wall  16 . 
     Refer to FIGS.  3 , 4  and  5  which schematically illustrate the feeding of bark dust and chips, and the like, (reference letter M) into the feeder bin  18 . As this material is pushed toward the rear end of the container  12 , the material M is first engaged by the rotating fingers or tines of the rake assemblies  34  which loosens the material from a somewhat compressed or compacted condition and directs the loosened material downward toward the augers  30  (FIGS.  4  and  5 ). The augers  30  are of the screw type with the flutes  72  being oppositely directed (one side versus the other side—See FIG. 4) and the pair of augers  30  being oppositely and inwardly directed (the inner auger versus the outer auger—see FIG.  5 ). Thus, material that is deposited onto the augers is directed from the sides toward the center and then downwardly into the feeder bin. This material flow is illustrated by arrows. Material that is not broken down into sufficiently small pieces will be crushed between the augers and the likelihood of bridging across the feeder bin opening is substantially reduced if not eliminated. 
     The arrangement of bark dust unloading system permits a single operator to unload and distribute the material M received in the container  12 . With reference to FIG. 1, the operator connects the hose  22  to the air conduit  21 . The hydraulic pump  40  is engaged and is rotatably driven by the transmission of the vehicle  14 . The control  58  is typically preset to accommodate the particular material being delivered. The rate of the blower system  20  is also controlled to control the rate of air flow through the air conduit  21 , the feeder bin  18  and the hose  22 . 
     In operation, the material is dislodged by the rake assemblies  34  and then fed by the augers  30  into the feeder bin  18  and out the hose  22 . As the material is thus dispensed, the resistance to wall movement is reduced and the wall  16  will then move toward the end gate  32 . When sufficient pressure is again built up, i.e., resistance to movement, the wall will stop to allow the feeding process to catch up. 
     The operator may vary the pressure applied by the wall  16  to control the rate of movement of the wall  16  which controls the rate of material being dispensed through the opening  18 . However, the preset controls automatically apply the preset pressure considered to be desirable for the material being dispensed and the operator may not have to make any alterations or minimal alterations. If desired, the operator may also start or stop the movement of the wall  16  at any time. The operation is thus capable of automatic operation but with the operator having full control of the dispensing procedure. 
     Refer now to FIG. 6 which illustrates an alternate embodiment for moving material M received in the container  12  to the rear of the container  12  and thus into feeder bin  18 . In place of the movable wall  16 , the container  12  has a movable floor (deck)  100  that is arranged to systematically move the material M received thereon to the opening  18 . Front wall  16 ′ remains fixed. 
     Referring also to FIG. 7, the floor  100  has multiple slats  110 ,  111  and  112  that are repeated in sequence across the width of the bin. Each slat designated as  110  is coupled to the other slats  110  by a coupling beam  120 . Each slat designated as  111  is coupled to the other slats  111  by a coupling beam  122  and each slat designated as  112  is coupled to the other slats  112  by a coupling beam  124 . A motor is provided for each of the coupled sets of slats in the form of a hydraulic cylinder  104 ′ provided for the coupled slats  110 , hydraulic cylinder  104 ″ is provided for the coupled slats  111  and hydraulic cylinder  104 ′″ is provided for the coupled slats  112 . 
     A valve unit  106  is provided to control the operation of the cylinders  104 . The cylinders  104  are controlled for operation in unison for rearward movement and for operation independently in forward movement. As will be explained, the alternating rearward movement in unison and forward movement independently produces material movement rearwardly. The rate of movement is controlled similar to that of moving wall  16 , e.g., with a pressure sensing device  56 ′ sensing material compression at end gate  32  and an adjustment control  58 ′ responsive to device  56 ′. 
     Referring now to the process of material movement, in this embodiment wall  16  is fixed and simply provides a space for the equipment as previously described. The material received on the slats (designated as  110 ,  111  and  112 ) is moved toward the feeder bin  18  by controllably moving the slats back and forth a limited distance through the operation of the cylinders  104 . 
     The material is moved toward the bin  18  by moving all of the slats  110 ,  111 , and  112  in unison (a limited distance as permitted by motors  104 ) toward the bin  18  as illustrated by the arrows  130  in FIG.  8 B. The material carried by the floor is accordingly moved with the slats. When the cylinders  104  have reached the end of their stroke, that is the slats  110 ,  111 , and  112  have been moved to their maximum stroke, one set of slats is then retracted forward, i.e., toward the wall  16 . For example, FIG. 8A shows the slats  110  being retracted toward the wall  16  (designated by arrows  132 ) while the slots  111  and  112  remain in position. The two sets of slats  111  and  112  being stationary retains the material as the slats  110  are retracted relative to the material. The other two sets ( 111  and  112 ) are then sequentially moved toward the wall  16  to reposition all of the slats and the material has accordingly been moved rearward relative to the floor in total. The process is repeated until all of the material has been moved to the rear of the bin where the material is engaged by the rake assembly  34  and auger assembly  30 . The sensor  56 ′ senses the compaction and through control  58 ′ the rate of movement is controlled. The material is accordingly moved to the bin  18  where it is dispensed out through the tube  22 . Control  58 ′ is pre-set as previously described and can be manually overridden by remote control  60  also as previously described. 
     Those skilled in the art will recognize that modifications and variations may be made without departing from the true spirit and scope of the invention. The invention is therefore not to be limited to the embodiments described and illustrated but is to be determined from the appended claims.