Abstract:
A mixing and delivery machine for flowable materials having on-site and towable mobility for mixing, hydrating, and delivering an admixture such as cementious mix, concrete, binder, graveled sand, mold sand and various other mixtures via an extended auger and elevatable hopper is used to facilitate both loading and releasing the hopper contents into the feed end of the auger. The auger is driven by a primemover and a wheel set on the machine facilitates the raising and lowering of the delivery end of the mixing auger.

Description:
BACKGROUND OF THE INVENTION 
     This application claims the benefit of Provisional Application No. 60/672,030 filed on Apr. 18, 2005. The disclosure of this provisional application is incorporated by reference as though set forth at length. 
    
    
     This invention relates to mixing and concomitant delivery of temporarily flowable solid materials at a use site. More specifically, this invention relates to mixing and delivery mixtures of concrete sand casting compositions, plates of paris compositions and the like. 
     There are a number of solutions to the problem of mixing and dispensing concrete; some of these demand use of heavy equipment while others use more specialized equipment and a number of personnel to operate the equipment. Other solutions involve lighter weight equipment or even portable equipment; yet much of the history of concrete making and placement on a small scale is characterized by the manual work of lifting, loading, mixing and manually hauling. 
     Complications revolve around mixing techniques including the need to control relative proportions of cement, sand and gravel and other additives. Substantial work has been completed in attempts to automate or mechanize proportioning of the ingredients. The need, of course, is to provide an end product that meets various building and construction code specifications. Moreover, there is general recognition within the community of those skilled in the art of handling that minimal handling or mixing of the hydrated concrete mixture is preferred prior to placement. 
     The use of dry premixed ingredients provides guaranteed proportions of the essential components without the end user having to be concerned about mixing proportions; further if the end user pre-mixes the dry components in a separate batch-type process rather than metering the ingredients in a continuous process the simplicity and reliability of the proportions is more readily achieved. Of course, it does not matter whether the end user actually performs the proportioning so long as the end user has assurance that a mix conforms to specified proportions. 
     As recommended by the Portland Concrete Association, the delivery and placement of a hydrated mixture should be performed with minimal handling and re-mixing once the initial hydrated mixture is created. Accordingly, both speed of placement and minimal handling are desirable features. Accordingly, facile handling with minimal personnel and minimal capital outlay for equipment is a desirable objective within the community of mixing and delivering concrete. 
     One prior arrangement comprises a wheeled concrete mixing device which incorporates a hopper mounted above a trailer frame. The trailer frame is linearly movable on track elements and delivers its contents to a conveyor belt located below the hopper. Here a two-hopper system is used and the second hopper feeds the flowable material to a screw conveyor. The second hopper in this system is rigidly mounted and fixed in relation to the trailer frame. 
     Another particulate mixer uses multiple hoppers fixed on a frame and the hopper support frame is also fixed in relation to a vehicle transport frame. In this system a set of feeding augers each driven by a separate hydraulic motor delivers contents to a final delivery auger. The final delivery auger is angularly fixed in relationship to the intermediate delivery augers during operation. Further the delivery auger is fixed in relationship to the ground because the final delivery auger exits to the side of the trailer frame. 
     Still another mixer uses a fully encased cover over a mixing and conveying auger and which uses the encasing cover as a structural frame support for the wheels, a towing hitch, a drive engine and a delivery hopper. An internal combustion engine driving the auger is located on the distal end of the auger assembly thus necessitating the placement of transport wheels near the distal end. This arrangement severely limits the adjustment of the delivery height of the distal or delivery end of mixing system and access to the auger chamber. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention presents a novel concrete mixing and delivery machine that employs a delivery hopper that can be pivotally elevated for supplying a flowable material to a powered auger that rotates within a confining chamber to provide a transporter for the flowable material. The moveable delivery hopper resides on a linkage system that permits the hopper to move into a lowered or loading position, which makes it convenient to load with flowable materials, and then permits the hopper to move into a raised or delivery position. In the delivery position, the hopper has a lower gate that facilitates movement of the flowable materials to a proximal end of the rotating auger. 
     The powered auger has a series of longitudinally spaced lift elements that urge the deposited mixture toward the distal end of the auger where the mixture exits the machine. This auger can be driven by a variable speed. Moreover, the auger can be serially segmented and different pitch of the blades can be selected in each segment to vary the rate of advancement. 
     A confining chamber for the auger is provided by a frame and side and bottom walls; this conveyor frame is attached to a main or base frame that houses the motive power for driving the auger and the linkage assembly that supports the hopper. 
     A set of wheels resides on the base frame and provides mobility on a work site; these transport wheels also create an angular adjustment capability for the delivery auger; a towing hitch resides at the distal end of the auger and provides road-type mobility. 
     Additionally, stabilizer arms operably extend from the base frame to provide overall stability of the machine as the delivery hopper is moved from the loading to the delivery position and vice versa. 
    
    
     
       THE DRAWINGS 
       Additional aspects of the present invention will become apparent from the following detailed description of the preferred embodiments thereof taken in conjunction with the accompanying drawing, which are for purposes of illustrating preferred embodiments of the present invention and not for purposes of limiting the scope of the invention: 
         FIG. 1  is an axonometric view taken from a front perspective of the machine and showing a cutaway of the conveying section; 
         FIG. 2  is another axonometric of a rear perspective showing a conveyor auger; 
         FIG. 3  is a side view of the machine depicted in  FIG. 1 ; 
         FIG. 4  is another side view of the machine with the side walls removed to disclose an interior auger delivery mechanism; 
         FIG. 5  is a front view of the concrete mixing and delivery machine shown in  FIG. 1 ; 
         FIG. 6  is a rear view of the machine depicted in  FIG. 1 ; 
         FIG. 7  is a plan view of the machine depicted in  FIG. 1 ; 
         FIG. 8  is a detail view of a segment of  FIG. 1 ; and 
         FIGS. 9   a - 9   f  show a side elevation sequence of views of the machine in various stages of operation. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Structure 
     Turning now to the drawings wherein like reference characters indicate the parts,  FIGS. 1 and 2  disclose perspective views for mixing and conveying machine  10  in accordance with the invention. The mixing and conveying machine includes a base frame  2  a hopper  14  mounted on the base  12  and a mixing and conveyor frame  16  behind carries a mixing and conveyor system  18 . The base  12  is mounted upon a set of wheels to facilitate transport as shown in  FIG. 1 . 
     The mobile hopper  14  has an openable port  20  on the lower end of the hopper to allow flowable material to be released. The hopper is preferably designed with square side walls  20  with generally inverted pyramid base  22 , a slidable gate  24  to selectively deliver an admixture from the hopper into the mixing and conveying system  18   
     The hopper side walls  20  are supported at the corners by angle iron legs  28  that are pivotally mounted to the base  12  as at  30 . The angle iron legs  28  are in turn pivotally connected to the side walls of the hopper  20  as at  32 . At approximately a mid portion of the conveyor frame is a cable winch  34  which may be hand operated or power driven as desired to raise and lower the hopper  20  in an operative manner that will be discussed below in connection with  FIG. 9 . 
     The conveyor frame  16  serves to support a mining and conveying system  18 . This conveying system includes a base end wall  36  and side walls  38  which join into an arcuate base to form a trough, note  FIGS. 2 and 5 . A drive shaft  42  is journaled at each end within the trough and is operably connected to a prime mover  44  such as a hydraulic or electric variable speed motor. The motor is geared to the shaft at a base or proximal end of the conveyor beneath the hopper  14 . 
     The drive shaft  42  operably carries a flight of auger blades  46  that serve to advance and mix material dropped into the trough from the hopper  14 . The rate of advancement can be adjusted by varying the speed of the drive system motor  44  or transmission connected between the motor  44  and shaft  42 . 
     In one embodiment the auger flights are mounted upon collars that are slid serially onto the drive shaft  42  and each segment is keyed to the shaft to rotate with the shaft. However, the pitch of each segment of auger blades may vary and thus the rates of advancement and mixing of the materials within the trough can be varied along the length of the trough. 
     Fluid can be added during the mixing and blending operation within the trough by a fluid line  50 , note  FIGS. 1 and 8  and a spray or drizzle nozzle head  52 , a valve  54 , which can be handled or remotely operated, serves to control the rate of fluid addition such as water to an admixture of concrete, solvent to a mixture of plastic particles, binder to sand for molding, and the like. 
     A distal end  56  of the mixing and conveying auger is supported by a hand adjustable stand  58 , note  FIGS. 3 ,  4  and  7  and an A-frame  60  terminates in a trailer hitch or eye opening  62  to facilitate transport of the unit on and to a job site. The distal end  64  of the mixing and conveyor system  18  is open and fluidized admixture are evicted from the trough by gravity through the A-frame  60  to a desired work location. 
     Operation 
     In operation the machine  10  is transportable to a worksite via conventional towing and is typically stationed as shown in  FIG. 9   a . Prior to beginning the loading operation for the movable delivery hopper  14  the stabilizer arms  60  are lowered and locked into ground engaging position as shown in  FIG. 9   b . The mobile hopper  14  is then lowered from a parked position to a loading position as shown in  FIGS. 9   b  thru  9   d  via the cable winch system  34 . Once the hopper has been loaded with dry ad mixture the winch system  34  is employed to return the hopper  14  into the parked or delivery position shown in  FIG. 9   e . Also as shown in  FIGS. 9   e  and  9   f  the towing hitch  60  can be removed, as an option, to allow free delivery of a hydrated ad mixture from the distal end  64  of the mixing conveyor  18 . 
     In the broadest sense the inventive machine is a general purpose mixing and delivery vehicle that mixes and conveys a delivery product to a useful port at the end of an auger. Such a machine finds ready utility in the manufacture of hydrated cement which undergoes initial hydration as the mix, which is initially dry, traverses the conveyor toward the distal delivery end of the system. By providing the various machine elements described in the foregoing paragraphs a ready mix cement product is produced in small and variable quantities as needed with the machine retaining the capability to supply large projects by either operating continuously or by continuing to supply batches or runs in quick succession so that a continuous pour or placement is accomplished. The instant inventive machine provides a solution to the problem of correct batch mix proportions by using a pre-mixed dry mixture that is received or loaded into the delivery hopper  14 . Prior attempts to accurately and carefully meter out the proportions of sand, gravel and Portland cement at the exit point for hopper systems present complicated arrangements that are not required in this machine. Either an off-site mixed dry mix is used or a separate dry mixing machine (not a part of this invention) is used to provide a properly proportioned dry mix. Of course, the invention is not limited to use in mixing and delivering concrete as other admixtures of sand and binder, plastic pellets and solvent, plaster of paris and water, and other mixtures can be made with the subject invention. 
     Once the dry mix is loaded into the delivery hopper the hopper is moved to the delivery position,  FIG. 9   e , and with the conveyor auger  46  rotating. The hopper delivery gate  24  is opened sufficiently to establish a continuous flow of dry mixture to fall by gravity onto the proximal end of the mixture and conveyor system. The hopper delivery gate  24  is manually operated by a lever arm  27  connected to a pivot and a linkage that connects to the slidable delivery gate  24 . As the dry mix is further mixed by the lifts on the conveyor screw or helicoidal mixing element  46 , a liquid supply system  50 - 52  provides the aqueous or other fluid component by way of a delivery hose joined to a quick connector on the delivery piping  50 . A control valve  54  provides for graduated metering of the aqueous component that exits the liquid supply system at a delivery port  52  which is optionally fitted with a nozzle to disperse the aqueous component onto the traveling dry mix. As the mixing continues along the transporter trough the hydration step is accomplished and a ready fresh mix of cement for mortar or concrete exits the delivery port at the distal end  64  of the conveyor frame  16 . 
     As has been inferred, the machine has a drive system to cause the auger  18  to rotate to deliver product. In this drive system the prime mover  44  which is optionally an internal combustion engine connected to a transmission and then to a prime sprocket gear on the proximal end of the auger shaft. The prime mover or drive engine produces the rotational forces to turn the auger. This rotational force producing prime mover is not limited to an internal combustion engine but could be an hydraulic or electric motor. The output shaft of the prime mover delivers high speed rotational forces via a drive pulley which typically accommodates a V-belt or a grooved belt to deliver force to the transmission input shaft. The flexible belt provides frictional engagement to the surfaces of the drive pulley and is trained around an input pulley that resides on the transmission input shaft. The transmission or gear box is a gear set or input-output variation device to reduce the high speed revolutions of the prime mover to make a suitable speed drive for rotating the auger. A gear shift lever  70  extends from the transmission to allow suitable speeds to be selected. An output sprocket resides on the transmission&#39;s output shaft and has an endless multi-link flexible chain trained around it and the prime sprocket gear to transfer the rotational forces from the transmission output shaft to the proximal end of the auger shaft  42 . 
     The movement of the hopper is controlled by a cable winch system  34  which provides a mechanical connection between the auger frame  16  and the moveable delivery hopper  14  to urge the movement of the delivery hopper from a loading position shown in  FIG. 9   d  to a delivery or parked position above the proximal end of the conveyor frame via a cable that is attached to the hopper by a hook eye. The dual parallelogram geometry of the hopper support arms  28  and arm stops control the center of gravity for the hopper to prevent travel over center allowing the cable winch system  34  to lower the hopper into the loading position by action of gravity. 
     In describing the invention, reference has been made to a preferred embodiment and illustrative advantages of the invention. Those skilled in the art, however, and familiar with the instant disclosure of the subject invention, will recognize additions, deletions, modifications, substitutions and other changes which fall within the purview of the subject invention.