Abstract:
A hopper assembly for a ready mixed concrete truck having a material off loading position and a material on loading position. The hopper assembly includes a main chute portion and a movable portion movable between an open position for off loading and a closed position for on loading. The movable portion directs material directly into an opening of a mixing drum providing for the rapid on loading from an overhead delivery apparatus when in the closed position. When the movable portion is in the open position or off loading position a passage area between the hopper assembly and the mixing drum is increased thereby eliminating a restricted area to provide for the effective dispensing of high viscosity material such as low slump concrete.

Description:
This application claims the benefit of U.S. Provisional No. 60/118,594, filed Feb. 4, 1999. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention generally relates to a loading hopper for a ready mixed concrete truck, and more particularly to a loading hopper having a movable portion which eliminates restrictions during the off loading of concrete. 
     Ready mixed concrete trucks currently receive the various materials that make up concrete through an overhead delivery system. The truck is located under a delivery chute and the materials are loaded directly into a mixing drum on the truck. The materials are commonly directed into an opening in the mixing drum of the truck by a hopper located adjacent to the mixing drum. The hopper is generally a funnel shaped device extending into an open angularly raised portion of the mixing drum. The hopper is thus located to direct the downward pouring material directly into the angled mixing drum. 
     Concrete is provided in various mixes dependent upon the intended use. To form curbs, gutters, and the like, a thick concrete having a particularly high viscosity is normally employed. This type of concrete is commonly referred to as low slump concrete as it retains the shape in which it is poured. To form a curb the low slump concrete is dispensed from the mixing drum into a slipform machine. A slipform machine is a self-propelled, tracked machine, which continuously molds low slump concrete into various freestanding dimensions without the use of stationary forms. The ready mix concrete truck moves along with the slipform machine to discharge the concrete into the slipform machine. 
     Unfortunately, the thickness of the low slump concrete, which makes it so effective in the formation of curbs, creates particular difficulties during the dispensing process. The component materials and the concrete are commonly on loaded and off loaded from the mixing drum through the same opening in the mixing drum and thus the hopper is located adjacent the mixing drum opening. This is normally acceptable when using a concrete having a standard viscosity as the mixing drum opening and the hopper are spaced to allow passage of the concrete from the mixing drum to the dispensing apparatus. Nonetheless, the low slump concrete viscosity prevents effective off loading from the restricted area between the hopper and mixing drum opening, thus slowing down the unloading process. 
     When the low slump concrete becomes restricted during the off loading process, the truck cannot discharge at a rate comparable to the ability of the slipform machine. Due to this, the slipform machine has to be repeatedly stopped to allow the truck to catch up with product delivery. This disrupts the smooth continuous operation of the slipform machine resulting in an increase of manual repair to the finished product (curb, barrier wall etc.). 
     To avoid the restriction problem, another expedient solution is commonly performed. The entire traditional hopper assembly is commonly hinged to the mixing drum and can be raised by pneumatic or hydraulic cylinders during cleaning or maintenance. The entire hopper assembly is thus commonly raised during the off loading process to completely eliminate interference with the low slump concrete off loading (FIGS. 4A,  5 A, and  6 A prior art). However, commonly known hopper assemblies are manufactured as one-piece funnel shaped structures, which can weigh several hundred pounds. This creates the danger that the entire hopper assembly could fall if pneumatic or hydraulic pressure is lost and thus injure a closely located individual. In addition, when the hopper assembly is raised, the overall vehicle height is increased by up to three feet. The increased height thus prevents the truck from passing under standard clearance height objects such as bridges and power lines, which farther restricts the curb laying process. 
     SUMMARY OF THE INVENTION 
     The present invention provides a hopper assembly, which solves the above disadvantages while further improving the serviceability and effectiveness of a ready mixed concrete truck during the dispensing of low slump concrete. 
     The present invention also provides a hopper assembly having a main chute portion and a movable portion located adjacent to a storage container such as a ready mixed concrete truck mixing drum. The movable portion is attached to the main chute assembly and is moveable between an open position and a closed position, which corresponds to a material off loading position and a material on loading position, respectively. 
     The hopper assembly of the present invention further includes an actuator to move the movable portion between the material off loading position and the material on loading position. The actuator preferably is a pneumatic or hydraulic cylinder attached to the main chute portion which actuates the movable portion through a linkage assembly to move the movable portion between a closed position and the open position away from the mixing drum. 
     To provide the rapid on loading from an overhead delivery apparatus, the movable portion is moved to the material on loading position. The hopper assembly is therefore configured to direct material into an opening of the mixing drum. For the effective dispensing of high viscosity material such as low slump concrete the movable portion is moved to the off loading position. A passage area between the hopper assembly and the mixing drum is thereby increased and the restriction between the hopper assembly and the mixing drum is eliminated. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Other advantages of the present invention will be readily appreciated, as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein: 
     FIG. 1A is a pictorial illustration of a standard front discharge concrete mixer truck including a prior art hopper assembly; 
     FIG. 1B is a pictorial illustration of a front discharge concrete mixer truck on loading concrete through a hopper assembly designed in accordance with the present invention in the closed position; 
     FIG. 2A is a front pictorial illustration of the prior art hopper assembly in a closed position; 
     FIG. 2B is a front pictorial illustration of the hopper assembly of the present invention in a closed position; 
     FIG. 3A is a front pictorial illustration of the prior art hopper assembly in an open position; 
     FIG. 3B is a front pictorial illustration of the hopper assembly of the present invention in an open position; 
     FIG. 4A is another front pictorial illustration of the prior art hopper assembly in the open position; 
     FIG. 4B is another front pictorial illustration of the hopper assembly of the present invention in the open position; 
     FIG. 5A is another front pictorial illustration of the height of the hopper assembly of the prior art hopper assembly in the open position; 
     FIG. 5B is another front pictorial illustration of the height of the hopper assembly of the present invention in the open position; 
     FIG. 6A is a close-up side pictorial illustration showing the height above ground of the hopper assembly of the prior art hopper assembly in the open position; 
     FIG. 6B is a close-up side pictorial illustration showing the height above ground of the hopper assembly of the present invention in the open position; 
     FIG. 7A is another side pictorial illustration of the height of the hopper assembly of the prior art hopper assembly in the open position; 
     FIG. 7B is another side pictorial illustration of the height of the hopper assembly of the present invention in the open position; 
     FIG. 8 is a pictorial illustration of the hopper assembly of the present invention in a closed position; 
     FIG. 9 is a pictorial illustration of the hopper assembly of the present invention in the closed position; 
     FIG. 10 is a pictorial illustration of the hopper assembly of the present invention in the closed position; 
     FIG. 11 is a pictorial illustration of the hopper assembly of the present invention in the closed position; 
     FIG. 12 is a pictorial illustration of the hopper assembly of the present invention in the open position; 
     FIG. 13 is a close-up pictorial illustration of the hopper assembly of the present invention in the open position; 
     FIG. 14 is a close-up pictorial illustration of the hopper assembly of the present invention in the open position; 
     FIG. 15 is a close-up pictorial illustration looking into the hopper assembly of the present invention in the closed position; 
     FIG. 16 is a close-up pictorial illustration looking into the hopper assembly of the present invention in the open position; 
     FIG. 17 is a close-up pictorial illustration looking into the hopper assembly of the present invention in the closed position while discharging concrete; 
     FIG. 18 is a close-up pictorial illustration looking into the hopper assembly of the present invention in the open position while discharging concrete; 
     FIG. 19 is a close-up pictorial illustration looking between the mixing drum and the hopper assembly of the present invention in the closed position while discharging concrete; 
     FIG. 20 is a close-up pictorial illustration looking between the mixing drum and the hopper assembly of the present invention in the closed position while discharging concrete; and 
     FIG. 21 is a close-up pictorial illustration looking between the mixing drum and the hopper assembly of the present invention in an open position while discharging concrete. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     A traditional hopper assembly  101  for a vehicle such as a concrete truck  20  is generally shown at a closed position in FIG.  1 A. The hopper assembly  101  includes a main chute assembly  102  located adjacent to a mixing drum  22 . The hopper assembly  101  is commonly of a funnel-like shape which extends into the mixing drum  22 . The mixing drum  22  is here shown installed on a front loading ready mixed concrete truck  20 . However one skilled in the art will realize that the present invention can be used on all manner of cement trucks including front and rear loading configurations. 
     FIG. 1B illustrates a front loading cement truck  20  having a hopper assembly  10  designed in accordance with the present invention during the material on loading process. As illustrated the material is commonly poured from an overhead manufacturing/storage area directly through the hopper assembly  10  into the mixing drum  22 . The hopper assembly  10  must withstand the force associated with the on loading process and is thus of a significant construction. A hopper assembly  10  or  101  will normally weigh several hundred pounds and, in the prior art, is affixed to the mixing drum  22  by hydraulic or pneumatic actuators which allow articulation of the entire hopper assembly  101  to an open position (FIGS. 4A,  5 A and  6 A) for cleaning and maintenance. 
     FIG. 2A illustrates a prior art hopper assembly  101  in the closed or on loading position. The prior art hopper assembly  101  is illustrated as having a vertical height of thirteen feet above the ground in this position. FIG. 2B illustrates the hopper assembly  10  of the present invention. It is apparent that the vertical height of the hopper assembly  10  is maintained at thirteen feet above the ground. 
     FIGS. 3A and 4A illustrate the one-piece prior art hopper assembly  101 , which is shown in the open position, as having a vertical height of approximately sixteen feet when in this position. This open position is sometimes used during a curb laying operation to prevent off loading restriction caused by the high viscosity low slump concrete becoming trapped between the mixing drum  22  and the hopper assembly  101 . In addition, it is readily apparent that the approximately sixteen feet height has the potential to interfere with standard clearance obstacles such as bridges and power lines, which are generally set at 13.5 feet above ground. Moreover, if the actuators were to fail, the entire prior art hopper assembly  101  could fall down to the closed position possibly causing damage or injury. The open position is also used for cleaning operations, wherein an operator stands below the raised hopper assembly  101  to clean the adjacent areas of the concrete truck  20 . 
     FIGS. 3B and 4B illustrate the present invention hopper assembly  10  in an open or off loading position, such as when dispensing low slump concrete while maintaining an overall vertical height of approximately thirteen feet as a movable portion  12  no longer depends upon movement of the entire hopper assembly  10 . 
     FIGS. 5A-B,  6 A-B, and  7 A-B show side by side comparisons of the prior art hopper  101  ( 5 A,  6 A,  7 A) and the hopper assembly  10  of the present invention ( 5 B,  6 B,  7 B) installed on an equivalent front loading cement truck. The open position shown in FIGS. 5B,  6 B and  7 B would again be the orientation most commonly used during the curb laying process or cleaning process. 
     FIGS. 8 and 9 are illustrations of the hopper assembly  10  of the present invention. The movable portion  12  is attached to a main chute portion  14  and an actuator  16  is attached therebetween. The actuator  16  provides the motive power to move the movable portion  12  between an open position and a closed position in relation to the main chute portion  14 . The actuator  16  is preferably a hydraulic, pneumatic, or a like cylinder attached at a first end to the main chute portion  14  at a pair of mounting ears  109 . Again, this movable portion  12  no longer depends upon the movement of the entire hopper assembly  10 . 
     The connection of moveable portion  12  to main chute portion  14  includes a linkage assembly  110  having a generally J-shaped link  112  pivotally mounted at its opposite ends to the main chute portion  14  and the moveable portion  12 , respectively. As illustrated, one end of the J-shaped link  112  is pivotally mounted to main chute portion  14  by a pair of ears  114  and a pin  116 . An opposite end  118  of link  112  is mounted to an arm  120 . The opposite end  118  has opposed ears  122  that are mounted over arm  120  and pinned to arm  120 . The ears  122  allow the opposite end  118  to pivot over arm  120  as link  112  is pivoted between the open and closed positions (see FIG.  10 ). As will be explained in greater detail below, the link  112  and the interaction of ears  122  pivoting over arm  120  permit a tighter closure of the moveable portion  12  with respect to main chute portion  14 . 
     The arm  120  is illustrated with a generally triangular mounting portion  123 , which in the preferred embodiment is welded to the moveable portion  12 . A free end  124  of arm  120  is pivotally mounted to a connecting bracket  126  which is in turn pivotally connected to the main chute portion  14  through a pair of mounting ears  128 . 
     A second end, opposite the first end, of the actuator  16  is pivotally mounted to link  112 . As illustrated in FIGS. 10-14, the actuator  16  retracts to open the moveable portion  12 . Due to the linkage assembly  110 , the moveable portion  12  is first forced away from actuator  16 , even though actuator  16  is pulling the J-shaped link in the opposite direction. This first movement separates an edge of the moveable portion  12  from an edge of the main chute portion  14 . This downward movement is caused by the J-shaped link  112  which when pulled rotates the arm  120  down slightly. 
     As the J-shaped link  112  is pulled back and up by actuator  16 , the moveable portion  12  slides back away from the main chute portion  14  in a direction generally parallel to the longitudinal axis of the vehicle  20 . In this way, the moveable portion  12  stays up close to the main chute portion  14  out of the path of concrete being dispensed. 
     As will be appreciated by those of ordinary skill in the art, an existing truck can easily be retrofitted with a hopper assembly  10  of the present invention. With reference to FIGS. 8-10 the moveable portion  12  can be cut from a traditional main chute. The bottom portion of the chute is cut along a line  140  shown in FIG.  10 . The linkage assembly  110  is then attached by welding ears  114  and  128  to main chute portion  14  and welding portion  123  to moveable portion  12 . The J-shaped link  112  and connecting bracket  126  can then be assembled and actuator  16  connected to mounting ears  109  and J-shaped link  112 . 
     FIGS. 10 and 11 are illustrations showing the hopper assembly  10  of the present invention located adjacent the mixing drum  22 . The movable portion  12  is shown in the closed position and is therefor aligned with the main chute portion  14 . This closed position is the position that allows the on loading of materials in the identical process currently used in traditional trucks. Materials poured into the hopper assembly  10  are directed by the main chute portion  14  and the movable portion  12  directly into the mixing drum  22  in the known manner. 
     FIGS. 12-14 illustrate the movable portion  12  in the open position. The movable portion  12  is moved out of the mixing drum  22  and preferably pulled up and against the main chute portion  14  by the actuator  16  and associated linkage assembly  110 . In this open position the movable portion  12  is not aligned with the main chute portion  14  and is generally perpendicular to the main chute portion  14 . This open position provides an increased passage between the hopper assembly  10  and the mixing drum  22  allowing the ready off loading of low slump concrete. 
     FIGS. 15 and 17 illustrate a view into the hopper assembly  10  to further show the movable portion  12  in the closed position and FIGS. 16 and 18 illustrate a view into the hopper assembly  10  to further show movable portion  12  in the open position. 
     FIGS. 19 and 20 show the passage area between the mixing drum  22  and the hopper assembly  10  in the closed position. The low slump concrete is shown in a first position during rotation and a second position further along in the mixing drum  22  rotation. It is clearly shown that the low slump concrete fills the passage area and the same concrete is retained in the mixing drum  22  thus increasing the off loading time. 
     FIG. 21 shows the same passage area as shown in FIGS. 19 and 20 but the movable portion  12  is in the open position. The movable portion  12  is here opened and stays along the main chute portion  14  to thereby create an enlarged passage area. The open position allows the continuous dispensing of low slump cement without the disadvantages of the prior art. 
     The present invention has been described in an illustrative manner, and it is to be understood that the terminology, which has been used, is intended to be in the nature of words of description rather than of limitation. 
     Obviously, many modifications and variations of the present invention are possible in light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.