Abstract:
A pigmentation dispenser utilizes a hopper having two rotors therein. One rotor moves the pigmentation material through an outlet opening and deposits it on a conveyor containing a concrete mix. The concrete mix and pigmentation material are then moved to a mixer which mixes them together.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     The present invention relates to an apparatus and method for adding pigmentation to concrete mix.  
         [0002]     In the mixing of concrete, there are two basic approaches. The first is the batch process which causes the concrete to be mixed in batches. A typical example of the batch process is the use of cement trucks which carry batches of the concrete and which mix the concrete during transport.  
         [0003]     The other method of processing concrete is the continuous method. In the continuous method, the concrete is continuously added to a conveyor which delivers the mixture of concrete and other materials to an auger mixer. The auger mixer then mixes the materials and discharges the mixed concrete continuously. A typical example of a continuous method is shown in U.S. Pat. No. 4,907,890.  
         [0004]     In either the continuous method or the batch method it is desirable on occasion to add pigmentation to the concrete mixture before it is mixed. Pigmentation materials are very difficult to handle because they are often finely divided particles which compact and which are difficult to handle.  
         [0005]     Therefore a primary object of the present invention is the provision of an improved apparatus and method for adding pigmentation to concrete mix.  
         [0006]     A further object of the present invention is the provision of an apparatus and method for adding pigmentation to concrete mix wherein a hopper and two augers are provided for loosening and dispensing the pigmentation material.  
         [0007]     A further object of the present invention is the provision of an improved apparatus and method for adding pigmentation to concrete mix wherein the augers or rotors include helical ribbon flighting having a central opening therein.  
         [0008]     A further object of the present invention is the provision of an improved apparatus and method for adding pigmentation to concrete mix wherein the hopper or bin includes sloped edges which converge toward a bottom auger or rotor.  
         [0009]     A further object of the present invention is the provision of an improved apparatus and method for adding pigmentation to concrete mix wherein a tube extends from the lower end of the hopper and an auger has a portion extending within the tube and a portion extending within the hopper.  
         [0010]     A further object of the present invention is the provision of an improved apparatus and method for adding pigmentation to concrete mix which is efficient in operation and which is simple and easy to manufacture.  
       BRIEF SUMMARY OF THE INVENTION  
       [0011]     The foregoing objects may be achieved by an apparatus for adding pigment to a concrete mixture. The apparatus comprises a hopper for containing pigmentation material to be added to the concrete mixture. The hopper has a lower end and an outlet opening adjacent the lower end for dispensing the pigmentation material from the hopper. A first rotor is mounted within the hopper above the outlet opening for rotation about a first horizontal axis. A second rotor is mounted within the hopper below the first rotor for rotation about a second horizontal axis. A drive system is connected to the first and second rotors for causing them to rotate about the first and second horizontal axis respectively. The second rotor is capable of moving pigmentation material to the outlet opening and causing the pigmentation material to be dispensed outwardly from the hopper through the outlet opening.  
         [0012]     A conveyor is located below the outlet opening of the hopper for receiving the pigmentation material dispensed from the outlet opening. The conveyor includes a concrete mixture thereon. The conveyor moves the concrete mixture below the outlet opening of the hopper so that the pigmentation material dispensed from the outlet opening is added to the concrete mixture. The conveyor has a discharge end adjacent a concrete mixer. The concrete mixer is adapted to receive the concrete mixture and the pigmentation material from the discharge end of the conveyor and to mix the concrete mixture and the pigmentation material together.  
         [0013]     According to another feature of the present invention the first rotor includes a helical flighting thereon. The helical flighting may be in the shape of a helical ribbon, but other types of helical flighting may be used.  
         [0014]     According to another feature of the present invention the first rotor includes radial beater bars for mixing the pigmentation material during the rotation of the first rotor. The second rotor may also comprise the helical flighting which may be in the shape of a helical ribbon or in some other helical shape.  
         [0015]     As used herein, the term rotor refers to an elongated rotatable member. The rotor may have helical flighting thereon, radially extending beater bars, or a combination of the two. The helical flighting may be typical helical flighting or it may be ribbon helical flighting having an open center therein. A primary object of the rotors is to move and agitate the pigmentation material. Agitation is important in order to break up the finely ground particles of pigmentation and the movement is required in order to discharge the pigmentation from the hopper.  
         [0016]     According to another feature of the present invention a mixing rod is attached to the helical flighting and is positioned off center from the longitudinal axis of the rotor. The mixing rod performs the function of holding the ribbon flighting together while at the same time providing a mixing function as it rotates about the longitudinal axis of the rotor.  
         [0017]     According to another feature of the present invention an exit tube is positioned adjacent the outlet opening of the hopper. The lower most auger extends within the exit tube and also extends within the bottom of the pigmentation hopper. The rotor is exposed to the pigmentation material at the lower end of the pigmentation hopper, but protrudes within the tube and rotates within the tube adjacent the outlet opening.  
         [0018]     The method of the present invention comprises placing the pigmentation within the hopper chamber. A first rotor is rotated to agitate and loosen the pigmentation material within the hopper chamber. A second rotor is rotated to cause the pigmentation material within the hopper to move toward and be dispensed outwardly through the outlet opening. The pigmentation material dispensed through the outlet opening is added to the concrete materials being conveyed below the outlet opening on a conveyor. The pigmentation material and the concrete material are deposited into a mixer and the mixer is used to mix the concrete materials and pigmentation materials together.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0019]      FIG. 1  is a sectional view of the present invention used in combination with a continuous concrete mixer.  
         [0020]      FIG. 2  is a sectional view taken along line  2 - 2  of  FIG. 1 .  
         [0021]      FIG. 3  is a sectional view taken along line  3 - 3  of  FIG. 1 . 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0022]     Referring to the drawings, the numeral  10  designates a conveyor of a continuous concrete processor. Conveyor  10  has a discharge end  12  and carries a concrete mix  14  which has been deposited on the conveyor. Adjacent the discharge end  12  of the conveyor is an auger mixer  16  having a lowered end  18  and a raised or upper end  20 . A motor  22  is attached to an auger shaft  24  which has helical auger flighting  26  thereon. A housing  28  surrounds the helical flighting and includes a rubber lower housing  30  and an inlet opening  32 . A discharge opening  34  is provided adjacent the discharge end of the auger mixer  16  and a shoot  36  is shown to carry the mixed concrete away.  
         [0023]     A pigmentation housing  38  is in the form of a hopper having opposite end walls  40 ,  42 , a V-shaped front wall  44  ( FIG. 2 ) and a V-shaped back wall  46 . As can be seen in  FIG. 2 , the V-shaped front and rear walls  44 ,  46  converge toward one another and meet at a rounded bottom  74 . A lid  48  is provided at the top of the hopper  30 . Within the hopper  30  is a hopper chamber  50 . The lid  48  includes a lid handle  54  and is pivotal about an axis provided by lid pivot  52 . The handle  54  can be used to raise the lid to insert pigmentation into the hopper chamber  50 .  
         [0024]     The lower end of the hopper  38  includes an outlet opening  56  which provides communication into the interior of hopper chamber  50  through a rotor tube  58 .  
         [0025]     A bottom rotor  60  includes an elongated helical ribbon  62 . The helical ribbon forms an open center ( FIG. 3 )  66 . An elongated rod  64  is welded or otherwise attached to the interior edge of the helical ribbon  62 . Rod  64  is located off center with respect to the rotational axis of the rotor  60  so that rotation of the rotor  60  causes the rod  64  to move in a circular path around the rotational axis and thereby agitate and loosen the pigmentation material within the housing chamber  50 . The bottom rotor  60  is rotatably mounted to end wall  42  by means of a bearing  68 . The opposite end of the rotor  60  is fitted within the rotor tube  58  to create an enclosed portion  76  of the rotor. The remainder of the rotor is designated by the numeral  78  and is in communication with the hopper chamber  50 . The ribbon section  78  of rotor  60  is exposed to the pigmentation and is not encased in any kind of tube. At the outer end of the rotor  60  is a large sprocket  70  and in addition, a small sprocket  72  is provided on this outer end outside the hopper  38 .  
         [0026]     A clean out  80  is best seen in  FIG. 2 . Clean out  80  is in communication with the interior of the hopper chamber  50  and is located at the lower most end and the rounded bottom portion  74  of the hopper  38 . A clean out plug  82  is removably inserted in the clean out  80  to normally prevent pigmentation from exiting through the clean out  80 .  
         [0027]     An upper rotor  84  includes a helical ribbon  86  which is attached to an elongated rotor shaft  88 . Also extending outwardly from the rotor shaft  88  are a plurality of radial beater bars  90 . The opposite ends of shaft  88  are mounted in the two opposite bearings  92 . A large sprocket  94  is mounted outside the hopper  38  and an idler sprocket  96  ( FIG. 2 ) is also mounted for rotation outside the hopper  38 .  
         [0028]     A motor  98  is mounted to the rear under surface of the hopper  38  and includes a first drive chain  100  which is trained around a sprocket  104  on the motor  98  and is also trained around the large sprocket  70  on the end of lower rotor  60 . A second drive chain  102  is trained around the small sprocket  72  on the lower rotor  60  and is also trained around idler sprocket  96  and the large sprocket  94  on the upper rotor  84 .  
         [0029]     In operation, the motor  98  is driven in a first rotational direction and causes rotation of the upper rotor  84  and the lower rotor  60 . Upper rotor  84  agitates the pigmentation and moves the pigmentation materials to the right as viewed in  FIG. 1 . Similarly, the beater bars  90  further agitate and loosen the pigmentation material. The lower rotor  60  moves the pigmentation material to the left as viewed in  FIG. 1 . The ribbon flighting  62  of the lower rotor  60  facilitates this moving action. At the same time, the rod  64  further agitates and loosens the material. The pigmentation material is moved outwardly and dispensed from the outlet opening  56  through tube  58 . It has been found that ribbon flighting on both the upper rotor  84  and the lower rotor  60  works best with the present invention. Other types of flighting may be used, but this has been found to be the most advantageous for loosening and moving the pigmentation material.  
         [0030]     The pigmentation material is then deposited on the conveyor and is designated by the numeral  106 . It is deposited on the concrete mix  14 . At the discharge end of the conveyor  10  the combination of the pigmentation material  106  and the other concrete materials  14  are deposited into the inlet opening  32  of the auger mixer  16 . The rotation of the auger mixer  16  causes the pigmentation and the other concrete materials to be mixed and ultimately discharged from dispensing opening  34 . Water may be added to the inlet opening  32  to create the desired concrete mix. The resulting mixture is designated by the numeral  108 , and includes the pigmentation material dispersed throughout the concrete mixture. The result is the pouring of concrete having the color provided by the pigmentation material  106 .  
         [0031]     When it is desired to clean out hopper  38 , the motor  98  is reversed and the plug  82  is removed from the clean out  80 . Reversal of motor  98  causes the lower rotor  60  to move the pigmentation material to the right as viewed in  FIG. 1  so that it drops out through clean out  80 .  
         [0032]     In the drawings and specification there has been set forth a preferred embodiment of the invention, and although specific terms are employed, these are used in a generic and descriptive sense only and not for purposes of limitation. Changes in the form and the proportion of parts as well as in the substitution of equivalents are contemplated as circumstance may suggest or render expedient without departing from the spirit or scope of the invention as further defined in the following claims.