Abstract:
The present invention is a front discharge transit mixer apparatus. In one form of the present invention the operator has an environment surrounde by a large viewing area so as to increase his ability to control the vehicle. Further, creature comforts include increased head room in the cab, air conditing, heat, and storage compartments. A total weight system is provided for assisting in maintaining the proper weight distribution of the apparatus for passage over roads and bridges.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    The present invention relates generally to transit mixers. More particularly, in one embodiment of the present invention, the transit mixer is of a front discharge type for mixing and transporting concrete to a job site.  
           [0002]    Transit mixers are well known in the construction industry and generally consist of a mixing drum mounted on a vehicle for the mixing and delivery of a batch of concrete. Raw materials, such as cement, aggregate, and sand are loaded into the mixing drum at a batching plant. During the transportation of the materials to the job site, the mixing of the raw materials and/or concrete is continued until the product is discharged at the job location for finishing.  
           [0003]    For many years, transit mixers were designed and constructed so that the loading and discharge was done from the rear of the transit mixer. Therefore, it was often necessary to back the large fully loaded vehicles into the job site in order to discharge a load of concrete to the proper place. Further, at many construction sites it was necessary to have an additional worker available to assist the driver in backing up the vehicle, and to prevent other parties at the job site from crossing the path of the vehicle as it was driven backwards. Rear discharge transit mixer designs have many inherent limitations that have a detrimental effect on the concrete producers.  
           [0004]    In response to the needs of the growing construction industry, a front discharge transit mixer was developed. The front discharge transit mixer has overcome many of the limitations associated with rear discharge transit mixers. For example, in a rear discharge mixer, the vehicle must generally be backed into the discharge position at the job site; the job site often is in a restricted drive area and the ability to place the rear discharge mixer proximate pouring location is compounded by the operators impaired rearward vision. In contrast, the front discharge transit mixer apparatus permits a more rapid and exact approach, with an improved view of the raw material charging and concrete discharging location. The ability to more accurately position the front discharge mixer will allow for more accurate control over the discharge of the concrete to the job site, which in turn, will reduce the amount of labor required to finish the concrete.  
           [0005]    While prior front discharge mixer apparatuses are steps in the right direction, there are still unmet needs in the transit mixer industry. The front discharge transit mixer of the present invention will address many of the unmet needs associated with prior front discharge transit mixers. The present invention satisfies these needs in a novel and unobvious way.  
         SUMMARY OF THE INVENTION  
         [0006]    One form of the present invention contemplates a transit mixer apparatus for transporting and mixing concrete. The transit mixer apparatus comprising: a vehicle chassis having a front end portion and a back end portion; a first pair of wheels coupled to the front end portion for supporting the chassis; a second pair of wheels coupled to the back end portion for supporting the chassis, a rotatable concrete mixing drum coupled to the chassis; the concrete mixing drum having a front end positioned above the front end portion and a back end positioned above the back end portion, the mixing drum having an opening at the front end through which concrete may be loaded into or discharged from the drum, the mixing drum inclined upwardly toward the front end portion; an operator cab positioned at the front end portion for an operator to ride in; and, a contaminant control system coupled to the cab for delivering a fluid to a portion of the exterior of the cab so as to reduce contaminants getting on the portion of the exterior of said cab.  
           [0007]    One object of the present invention is to provide an improved front discharge transit mixer apparatus.  
           [0008]    Related objects and advantages of the present invention will be apparent from the following description.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0009]    [0009]FIG. 1 is a side elevational view of a front discharge transit mixer apparatus of the present invention.  
         [0010]    [0010]FIG. 2 is a front elevational view of the FIG. 1 front discharge transit mixer apparatus.  
         [0011]    [0011]FIG. 3 is a rear elevational view of the front discharge transit mixer apparatus of FIG. 1.  
         [0012]    [0012]FIG. 4 is an illustrative side elevational view of the transit mixer of FIG. 1 with a pivotable front tower structure depicted in a first upright position and in a second rotated position.  
         [0013]    [0013]FIG. 4 a  is a partial side elevational view of a front discharge transit mixer having a charging hopper with a pivotable tongue portion that is in a first lowered charging position.  
         [0014]    [0014]FIG. 4 b  is a partial side elevational view of the FIG. 4 a  front discharge transit mixer with the pivotable portion of the charging hopper in a second elevated discharging position.  
         [0015]    [0015]FIG. 5 is a side elevational view of the chassis and drive train comprising a portion of the FIG. 1 front discharge transit mixer apparatus.  
         [0016]    [0016]FIG. 6 is a top plan view of the chassis and drive train comprising a portion of the FIG. 1 front discharge transit mixer apparatus.  
         [0017]    [0017]FIG. 7 is a side elevational view of a power pack module comprising a portion of the FIG. 1 front discharge transit mixer apparatus.  
         [0018]    [0018]FIG. 8 is a side elevational view of the moveable rear grill comprising a portion of the FIG. 7 unitary power pack module.  
         [0019]    [0019]FIG. 9 a  is a front elevational view of the operator cab comprising a portion of the FIG. 1 front discharge transit mixer apparatus.  
         [0020]    [0020]FIG. 9 b  is a side elevational view of the operator cab comprising a portion of the FIG. 1 front discharge transit mixer apparatus.  
         [0021]    [0021]FIG. 9 c  is a rear elevational view of the operator cab comprising a portion of the FIG. 1 front discharge transit mixer apparatus.  
         [0022]    [0022]FIG. 10 is a perspective view of the interior of the operator cab comprising a portion of the FIG. 1 front discharge transit mixer apparatus.  
         [0023]    [0023]FIG. 11 is a perspective view of the interior of the operator cab with structure removed to illustrate the duct work comprising a portion of the FIG. 1 front discharge transit mixer apparatus.  
         [0024]    [0024]FIG. 12 is an illustrative view of the input and output module for the integrated weight system comprising a portion of the FIG. 1 front discharge transit mixer apparatus.  
         [0025]    [0025]FIG. 13 is a diagrammatic illustration of the weight system comprising a portion of the FIG. 1 front discharge transit mixer apparatus.  
         [0026]    [0026]FIG. 14 is a side elevational view of an the FIG. 1 front discharge transit mixer with a mixer control unit being operated remotely from the cab.  
         [0027]    [0027]FIG. 15 is a plan view of the mixer control unit comprising a portion of the FIG. 14 transit mixer.  
         [0028]    [0028]FIG. 15 a  is a side elevational view of the mixer control unit of FIG. 15.  
         [0029]    [0029]FIG. 16 is a side elevational view of an alternate embodiment of the front discharge transit mixer apparatus having a different size mixer barrel mounted thereon.  
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0030]    For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiment illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated device, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.  
         [0031]    With reference to FIG. 1, there is illustrated a front discharge transit mixer apparatus  10 . The front discharge transit mixer apparatus  10  being designed and constructed for mixing and transporting raw materials and/or concrete to a job site. While the invention was designed for transporting raw material and concrete it has applications for the movement of fertilizer, limestone, rock, and sewage. Further, in an alternate embodiment the transit mixer apparatus  10  is utilized to spread sand, salt, gravel, or other products on a road surface during the winter season. The front discharge transit mixer apparatus  10 , includes a charging hopper  20 , an operator cab portion  30 , a mixing barrel  40 , a power plant portion  50 , and a vehicle chassis and drive train  60 .  
         [0032]    The moveable charging hopper  20  is utilized to receive and convey raw materials, such as cement, aggregate, sand, etc., from a filling location to the interior volume of the mixing barrel  40 . A filling location includes, but is not limited to, a concrete batch plant. In one form of the present invention the charge hopper  20  is pivotally mounted to a supporting structure  21  that is coupled to the vehicle chassis  60 . Charging hopper  20  having an extended tongue (not illustrated) that is moveable through an opening  41  at the front end of the mixing barrel, and continuing into the interior volume of the mixing barrel  40  to facilitate the placement of raw materials therein. Upon preparing to discharge a batch of concrete, the charging hopper  20  is pivoted to remove the tongue from the mixing barrel  40 , thereby allowing the discharge of the concrete from the mixing barrel  40  with a minimum of interference.  
         [0033]    The mixing barrel  40  which is of a generally well known design has a back end  40   a  and a front end  40   b . Mixing barrel  40  being supported and rotatable on a front mixing barrel mount  42  and a rear mixing barrel mount  43 . The mixing barrel having two frustum-conical portions  44  and  45  that are joined together to form the mixing barrel. The first portion  44  having a longitudinal length ‘ 1 ’, the second portion  45  having a length ‘c’. A rotation means  46  is utilized to rotate the mixing barrel  40  about a centerline z, and in the preferred embodiment the rotation means  46  is a hydraulic motor. The mixing barrel&#39;s front end  40   b  is inclined upwardly relative to the back end  40   a , and in the preferred embodiment is inclined at an acute angle θ. It is preferred that angle θ is about 12°. It is understood that other values for θ, and other mixing barrel designs are contemplated herein.  
         [0034]    Operator cab  30  is located at the front end.  61  of the vehicle chassis  60 . Cab  30  having tan interior operator space for accommodating an operator who controls the front discharge transit mixing apparatus  10 . The cab  30  has a six-sided surround vision which includes a large front windshield  31 , a pair of side windows  32  (only one illustrated), and a pair of rear side windows  33  (only one illustrated). The enhanced field of view through the surround vision includes the ability for a typical operator sitting in a normal driving position (one who is of normal size, proportions, and senses) to see a marking X located a distance m from the front end  11  of the transit mixer  10 . The marking X being a relatively flush marking located on the surface over which the transit mixer will pass. In one form of the present invention the distance m is about five feet. Further, the interior operator space extending to within six inches from the front end  11  of the transit mixer  10 .  
         [0035]    Power plant  50  is coupled to the chassis  60  and provides the motive power to propel the transit mixing apparatus  10  to the job site. The transit mixer apparatus  10  being designed to operate on a litany of surfaces including paved roads, unpaved roads, and undeveloped land. In the preferred embodiment the power plant  50  includes a water cooled internal combustion engine and transmission for delivering power to a plurality of drive axles on chassis  60 .  
         [0036]    Referring to FIG. 2, there is illustrated a front elevational view of the front discharge transit mixer apparatus  10 . The moveable charging hopper  20  is coupled to the supporting structure  21  which includes a pair of spaced upstanding structural supporting members  22  that are coupled to a pair of brackets (not illustrated) that connect to the chassis  60 . The upstanding structural supporting members  22  are spaced a distance ‘s’ apart to allow a wider cab  30  to be placed therebetween. In the preferred embodiment the distance &#39;s&#39; is about 65 inches. A pivotable front discharge chute  23  is coupled beneath the barrel opening  41  to receive the concrete being discharged from the barrel and convey it to the finishers at the job site. There are a multitude of chute designs that are capable of being coupled with the pivotable front discharge chute  23 , and these types of chute designs are generally known to those of ordinary skill in the art. A front lift  600  is coupled between: the chassis  60  and the pivotable front discharge chute  23 . The front lift  600  being extendable and rotatable with the chute. In the preferred embodiment the front lift  600  is hydraulically actuated. Extension or retraction of the front lift  600  will cause the raising or lowering of chute  23 . A wrap around front bumper  62  provides protection for the front end  11  of the transit mixer apparatus  10 . The front bumper  62  being designed for ease of removal to allow access to the chassis  60 .  
         [0037]    With reference to FIG. 3, there is illustrated a rear elevational view of the front discharge transit mixer apparatus  10 . The front discharge transit mixer apparatus  11  having a wide low profile hood  51  that encloses storage boxes, tool boxes, and the battery. The storage boxes, tool boxes and battery being protected by the hood  51  from the environment and unauthorized access. A rear frame shroud  52  covers the chassis  60  and extends to the rear bumper  63 .  
         [0038]    With reference to FIG. 4, there is illustrated one form of the supporting structure  21  that is pivotally coupled to the vehicle chassis  60 . In the preferred embodiment a pin and clevis assembly  601  holds the supporting structure  21  to the vehicle chassis  60 . Upon removeal of a plurality of fasteners the supporting structure  21  is uncoupled from a second series of support members  602  thereby allowing the supporting structure  21  to rotate to a forward folded position. It is understood herein that the support structure is only illustrated in two positions, however there are an infinite number of positions between the fully upright position and the fully folded position. Further, the front lift  600  is designed such that it can raise and lower the support structure  21  as the structure is rotated between positions. In one embodiment the chute  23  is rotated to a forward position, thereby placing the front lift  600  in a position for raising and lowering the supporting structure  21 . Upon the removal of the fasteners and the actuation of the front lift  600 , the supporting structure  21  can be rotated downward so as to allow access to the apparatus  10 .  
         [0039]    With reference to FIGS. 4 a  and  4   b , there is illustrated a partial side elevational view of the transit mixer apparatus  10  having an alternative embodiment of charging hopper  90  coupled thereto. A mechanical actuator  91  is coupled between a stationary portion of the hopper  90  and a moveable portion  612  of the hopper  90 . In the preferred embodiment, the actuator  91  defines a hydraulic cylinder that is moveable between an extended and retracted position so as to cause the moveable tongue portion  612  to pivot about a pivot point  613 . The moveable portion  612  being pivotally coupled to the stationary portion  611  of the hopper  90 . However, it is understood that other actuators capable of causing the moveable portion  612  to pivot such that it&#39;s distal end  614  is raised in a substantially vertical direction are contemplated herein. The stationary portion  611  is for receiving materials from a filling site to charge the mixing barrel  40  with raw materials.  
         [0040]    In order to facilitate filling of the barrel  40  the actuator  91  is retracted to cause the moveable portion  612  of the hopper  90  to rotate in a clockwise direction about pivot point  613  so that the distal end  614  extends beyond the second helical flight  42  in the barrel  40 . Charge hopper  90  is not intended to contact the helical flight or the inner surface  48  of the barrel. After the mixing barrel  40  has been charged with raw materials the mechanical actuator  91  is actuated so that it extends and causes the moveable portion  612  to rotate in a counterclockwise direction about pivot point  613 . This counterclockwise rotation causes the substantial vertical movement of the distal end  614  away from the helical flights within the barrel  40 , thereby to allowing the subsequent discharge of material from the barrel with minimum interference. More specifically, in FIG. 4 b , the moveable portion  612  is illustrated in a second raised position, where the distal end  614  is moved vertically away from the helical flights so as to minimize the interference between the concrete being discharged and the hopper  90 .  
         [0041]    In a preferred form of the present invention the helical flights (such as helical flight  42 ) extend about eleven inches from the inner surface  48  of the mixing barrel. During charging of the mixing barrel it is preferred that the distal end  614  is maintained about one inch from the helical flight  42 . In the second discharging position utilized for discharging material from the mixing barrel it is preferred that the distal end  614  is spaced about six inches from the helical flights to allow for the passage of material therebetween. It is understood herein that the movement between the first position and the second position includes rotation about pivot point  613  such that the distal end  614  is moved in a substantially vertical direction so as to change the clearance between the helical flights and the moveable portion  612  of the hopper  90 .  
         [0042]    With reference to FIG. 5 and FIG. 6, there is illustrated the vehicle chassis  60 . The chassis  60  includes a pair of spaced parallel substantially elongated structural members  53  and  54 . In the preferred embodiment the members  53  and  54  are unshaped (channel) frame rails that are oriented substantially parallel to a reference plane K. A pair of storage compartments/tool boxes  503  are positioned within the chassis  60  and covered by the hood  51  when it is closed. The design and construction of chassis  60  includes structural cross members to obtain the desired structural characteristics. Further, chassis  60  has a longitudinal centerline q. In one form of the present invention the chassis has a steering angle in the ranged of 25-35°. It is mote preferred that the steering angle be about 35°. However, other steering angles are contemplated herein.  
         [0043]    A plurality of axle assemblies are coupled to the chassis by suspension components to enable the apparatus  10  to roll. The chassis  60  having a front portion  64  and a back portion  65 . In describing of the suspension components associated with the plurality of axles hereinafter, generally only one side of the axle will be set forth as the other side is substantially identical. A first drive axle assembly  66  is coupled to the front portion  64  of the chassis  60 . The first drive axle assembly  66  includes a pair of driven axles that transmit the driving power from the power plant  50  to the vehicle wheels and tires. A pair of air springs  67  are positioned between each axle of the drive axle assembly  66  and the respective structural members  53  and  54 . In the preferred embodiment there are four air springs  67  coupled to the first drive axle assembly  66 . A plurality of suspension links, including beams and torsion bars are utilize to complete the drive axle assembly  66 . The air springs  67  allow the monitoring of pressure, the selective variation of pressure therein, the ability to raise and lower the apparatus  10 , and a way to change the load carried by each axle. In an alternative embodiment conventional leaf springs are positioned between each axle and the respective structural members  53  and  54 .  
         [0044]    A second axle assembly  68  is coupled to the chassis  60  and is a non-drive axle that functions to distribute the load of the apparatus  10  on the surface beneath it. An air spring  69  is disposed between each side of the axle  70   a  and  70   b  and the respective structural members  53  and  54 . Thus, in the preferred embodiment the second axle assembly  68  has a pair of air springs  69  that allow the monitoring of pressure therein, the selective variation of pressure therein, the ability to raise and lower the apparatus  10 , and a way to change the load carried by each axle.  
         [0045]    A third axle assembly  71  is coupled to the chassis and is a drive axle assembly that includes a pair of driven axles for transmitting power to the assemblies wheels and tires. An air spring  72  is disposed between each side of the axle assembly  71   a  and  71   b  and the respective frame rails  53  and  54 . Thus, in the preferred embodiment the third axle assembly  71  has a pair of air springs  72  associated therewith that allow the monitoring of pressure, the selective variation of pressure therein, the ability to raise and lower the apparatus  10 , and a way to change the load carried by each axle. Positioned longitudinally from the third axle assembly  71  is a fourth axle assembly  73 . The fourth axle assembly  73  is substantially identical to the third axle assembly  71 .  
         [0046]    A fifth axle assembly  76  is coupled to the chassis  60  and is a non-drive assembly that functions to distribute the load of the apparatus  10  to the surface beneath it. An air spring  77  is disposed between each side of the axle  76   a  and  76   b  and the respective structural members  53  and  54 . Thus, in the preferred embodiment the fifth axle assembly  76  has a pair of air springs  77  that allow for variations in the height and the load carried by the axle assembly. The fifth axle assembly  76  is coupled proximate the back end portion  65  of the chassis  60 . Further, the fifth axle assembly  76  is substantially identical to the second axle assembly  68 .  
         [0047]    In the preferred embodiment of the present invention each of the axle assemblies is independently controlled to allow the operator to adjust the inflated height of the air spring, the pressure within the air spring, and the load carried by each axle. In one form of the present invention the suspension includes air springs fro each axle assembly, thus a total airride is obtained. Further, each air spring is independently controlable to allow for vertical movement of each axle, pressure change for each axle as necessary to meet load and operating conditions. Further, the provision of a total air ride system will enable a weight system to be controlled by the operator. The apparatus  10  of the present invention contemplates other axle configurations, and is hot intended to be limited to five axle assemblies. In an alternate form of thee present invention axles supported by other means than air springs is contemplated. Further, a hybrid chassis in which some axles are supported by conventional springs and others are supported by air springs is contemplated herein.  
         [0048]    The power pack module  50  includes an internal combustion engine  55 , a multi-speed transmission  56 , a hydraulic pump  57 , an exhaust stack  58  and a battery  59 . The power from the engine  55  is transmitted through a drive train including drive shafts, universal joints, and a transfer case  100 . Transfer case  100  is utilized in a conventional fashion to enable power to be transmitted to the plurality of drive axles located along the chassis  60 . The engine and drive train configurations are considered to be within the scope of a person of ordinary skill in the art.  
         [0049]    A fluid reservoir tank  74  is mounted upon the chassis  60  to hold a quantity of fluid therein, and in one embodiment the fluid is water and the tank is sized to hold about 150 gallons thereof. The liquid within the tank is pressurized so that a discharge of pressurized liquid can be made from the mobile vehicle. A second fluid reservoir  75  is mounted upon the chassis  60  to hold compressed gas, and in the preferred embodiment the compressed gas is air. An onboard air compressor (not illustrated) is provided for compressing air for use by the plurality of pneumatic operated devices on the chassis, including air springs, air brake booster, pneumatic cylinders, etc.  
         [0050]    With reference to FIGS. 11 and 6 there is illustrated a depiction of the surround vision associated with cab  30 . The surround vision enables a typical operator normally seated in an operating position (one who is of normal size, proportions, and senses) to see a marking located a distance from the cab of the transit mixer. The marking being a relatively flush marking located on the surface over which the transit mixer will pass. In one form of the present invention the distance m is about five feet and the distance m′ is about four feet.  
         [0051]    Referring to FIGS. 7 and 8, there is illustrated a side elevational view of a removable modular power pack assembly  101  that is removeably coupled to the structural support members  53  and  54 . The power pack assembly  101  includes, but is not limited herein to, the internal combustion engine  55 , transmission  56 , exhaust stack  102 , radiator  103 , hydraulic pump  57 , and a battery  59  (FIG. 6). Coupled to and extending from the internal combustion engine  55  is a radiator fan (not illustrated) that is disposed within a radiator fan shroud  54  that connects to the radiator  103 . An air conditioning condensor  505  mounted between the fan and the internal combustion engine  55 . The fan acting to draw air across the condensor  505  to extract heat therefrom. In one form of the present invention the radiator  103  is a cross flow radiator, that by definition has the coolant passing substantially horizontally.  
         [0052]    In one form of the present invention the power pack assembly  101  defines a structural framework  200  having a pair of opposed rails  79  and  80  (not illustrated) that extend along the structural member  53  and  54  at the back end potion  65  of the chassis  60 . Further, the power pack frame has a cross member  81  that extends between the opposed frame rails  79  and  80  and supports radiator  103  thereon. A hydraulic pump  57  is coupled to and supported by the crossmember  81 . The hydraulic pump is utilized to supply pressurized hydraulic fluid to components within the front discharge transit mix apparatus  10 , such as the hydraulic motor  46  that causes rotation of the mixing barrel  40 . The power pack assembly  101  is removable from the chassis  60  by the disconnection of the driveshaft connecting to the universal joint  105 , uncoupling of some fluid and electrical lines, and uncoupling a plurality of the fasteners  150  passing through the frame rails  79  and  80  and into the chassis structural support member  53  and  54 . In the preferred embodiment, the power pack assembly  101  is removable as an integral unit including the hood  51 , the above power pack components and the mechanical actuation system  106  for raising and lowering the hood. Further, in another form of the present invention the mechanical actuation system  106  is defined by a pneumatic cylinder that is coupled between the power pack framework  200  and the hood  51 . Actuation of the pneumatic cylinder will raise and lower the hood  51  as required by the machine operator. In a preferred embodiment, the mechanical actuator  106  is activated by a push button located on the hood to allow the hood  51  to pivot to an open position.  
         [0053]    In one form of the transit mixer apparatus  120  the grill assembly  506  is pivotally coupled to the hood  51 . Rotation of the grill assembly  506  away from the hood  51  allows access to portions of the power pack assembly  101  without having to open the hood  51 . A hinge  507  couples the grill assembly  506  to the hood  51 . In an alternate embodiment a removeable grill assembly is utilized.  
         [0054]    With reference to FIGS. 9 a ,  9   b , and  9   c , there is illustrated the modular operator cab unit  30  that is coupled to the chassis  60  by conventional body shock mounts. In the preferred embodiment the cab  60  is made of a corrosion resistant material, such as stainless steel, fiberglass, or a composite material. In the preferred embodiment the cab is formed of stainless steel. Further, the cab  30  has an enlarged volume, and it is more preferred that the cab have a volume of about 93.2 cubic feet, and a glass surface area of about 37.4 square feet. The ratio of the surface area of glass to volume of the cab is greater than 0.33/(unit of length). It is more preferred that the ratio of the surface area of glass to the volume of the cab is about 0.40/(unit of length). Other surface areas of glass and cab volumes are contemplated herein, provided they enable the necessary operator room and enhanced visability for the operator.  
         [0055]    Cab  30  has a plurality of windows mounted for enhancing the operators field of vision. More specifically, a surround vision for the operator is created by having large window surface areas on six sides of the cab. The large window surface areas include the front windshield  31 , a pair of side windshield fairing  34 , a side door glass  32 , an opposing side window on the body (not illustrated) and a pair of side light windows  33  (only one illustrated on the sides of the cab). Further, there is a pair of back light windows  35 . The large surface area of glass contributes to the operator&#39;s ability to more easily see and control the environment in which he is working.  
         [0056]    In one form of cab  30  there is coupled thereto a contaminant barrier system  35 . The contaminant barrier system  35  is for dispensing a fluid over at least a portion of the cab to prevent the contamination of the dab with dust and foreign particles from the environment. More particularly, the contaminant barrier system  35  is designed to minimize the depositing of raw materials from the filling site (batch plant) onto the cab  30 . The operator can activate the contaminate barrier system  35  as required to thwart the depositing of material on the cab  35 . Further, the contaminant barrier system  35  can be activated at other times as deemed necessary by the operator.  
         [0057]    A fluid conduit  36  wraps around three sides of the cab  30  and is located at the upper portion of the cab  30  in about the same location where a drip rail is normally positioned. The contaminant barrier system  35  is well suited for preventing contamination of the cab  30  while the charging hopper is being filled under a batching station. The fluid conduit  36  carries a pressurized fluid to a plurality of apertures  37  that are spaced along the fluid conduit  36 . In one form of the present invention the apertures  37  are about 0.060 inches in diameter. It is preferred that the fluid for dispensing comes from the storage tank  74 , however it is contemplated that external sources of fluid could be utilized with the contaminant barrier system  35 .  
         [0058]    In a more preferred form of the present invention, the fluid circulating through the fluid conduit  36  is pressurized water that is discharged through apertures  37  that are oriented vertically downward to spray a mist across the body. The fluid mist extends across the surface area of the glass windows. Other liquids are contemplated for circulation through the conduit  36 , including cleaning agents, antifreezes, etc. The fluid exiting the apertures  36  provides a water barrier to minimize or block the transmission of dust and debris onto the exterior surface of the cab  30 , the exterior surface includes windows, doors and the cab body excluding the roof. Fluid conduit  36  is also in fluid communication with the pressurized gas stored in tank  75 . In the preferred embodiment the pressurized gas is air. However, other types of gases are contemplated herein.  
         [0059]    One application of the contaminant barrier system  35  is to discharge liquid, preferably water, from the plurality of apertures  37  so as to provide a liquid barrier to minimize or prevent contaminants from contacting the exterior surface of cab  30 . Upon completion of the liquid discharge portion of the operator can activate the delivery of the compressed gas through the fluid discharge conduits  36  and apertures  37  in order to dry the cab surface. Further, in another embodiment the deployment of compressed gas is contemplated as the fluid to prevent the contamination of the cab with foreign material.  
         [0060]    Referring to FIG. 10, there is illustrated an interior perspective view of a portion of the operator cab  30 . The operator cab  30  has a floorboard  150  that is substantially parallel to the top of the chassis  60 . The provision of a substantially flat floorboard  150  will allow the brake booster  151  to be mounted in a horizontal position. Further, in one form of the present invention the floorboard  150  is mounted such that it is positioned beneath the top of the chassis  60 . The positioning of the floorboard  60  beneath the top plane of the structural members  53  and  54  allows for an extended cab interior height without increasing the overall height of the apparatus  10 . The front discharge transit mixer  10  has been designed to have a minimum height less than about 13 feet and one inch, which will allow it to pass beneath concrete patching plants, and meet the Department of Transportation&#39;s specification for bridge heights. Further, in an alternate embodiment having air springs the minimum height is designed to be about twelve feet ten inches. It is understood herein that other floor configurations are contemplated for the operator cab.  
         [0061]    The location of the operator seat  152 , on the floorboard  150  that descends beneath the plane at the top of the structural member  53  and  54 , enables an operator, normally positioned within the seat to sit in an upright fashion without engaging the ceiling of the cab with their head. For clarity, the operator is a normal-sized, normal proportioned person less than six feet in height. Positioned on either side of the operator are operator comfort consoles  153  and  154 . The comfort console  153  is formed adjacent an operable door  155  that allows the passage of parties into and out of the cab  30 . In one form of the present invention, a liquid refreshment cooler holder  156  is coupled to the cab  30 . The liquid refreshment cooler holder  156  is designed and configured to receive a readily available cooler  57 . In a preferred embodiment the cooler holder  156  is integrally formed with the comfort console  153 . Positioned proximate the refreshment cooler holder  156  is a bulk beverage holder  158 . The bulk beverage holder  158  is designed to hold a quantity of fluid for consumption by finishers at the jobsite. The second operation comfort console  154  includes a plurality of modular instruments and control panels for which the operator can control the operation of the apparatus  10 . More particularly, creature comfort portion  67  has a plurality of storage holders for creating a more enjoyable and comfortable environment for the operator. Positioned proximate the front  175  of the cab  30  is a storage compartment  176  for storing items that are desirable to keep within each of the operator. Positioned adjacent the armrest  177  of the cab is a storage compartment  178  with a sliding lid  507  for placing documents, records and other information that the operator may need to transact business at the customer&#39;s location. Positioned within the storage compartment  178  is a beverage cup holder and other storage compartments.  
         [0062]    Positioned at an ergonomically preferred location is the drive train selector  180  and a mixing apparatus control  181 . Further, positioned adjacent the operator is a climate control module  183  that allows the operator to control the heater, air conditioner and fan. In one form of the present invention the cooling system has a 25,500 BTU output and the heating system has a 41,200 BTU output. Other heating and cooling capacities are contemplated herein.  
         [0063]    The operator from his vantage point in seat  184  can move (FIG. 6) the steering console to a variety of positions in order to make the operation of the vehicle more comfortable. In the preferred embodiment, the steering console is a tilt steering console, having a range of movement between 15-45°. Further, the dash module  190  is connected to the steering console and the steering console and dash module  190  are designed and constructed to move together as a unit. Other types of movable steering consoles are contemplated herein, such as a telescopic steering console. In the preferred embodiment, the dash module  190  moves freely under the control of the operator relative to the cab  30 .  
         [0064]    Referring to FIG. 11, there is illustrated a perspective view of the interior of the operating cab  30 , with the interior  26  trim and sheet metal skin removed to illustrate the internal duct utilized for the heating, air conditioning and ventilation system is located. The interior duct work  250  has been built into the body of the cab  30  to provide a passageway for the movement of air to the operator environment and to the respective discharge outlets  251  positioned adjacent each window in the scab. Further, an additional discharge outlet provides for the discharge of air to the operators leg and foot areas. A high-volume air conditioner and heating unit  252  is positioned behind the operator&#39;s seat  184 . The unit  252  being connected to the duct work  250  for transmission of air to the registers/discharge outlets  251 . The incorporation of the climate control system into the operator cab  30  not only enhances the operator&#39;s comfort level, but also allows for the prevention or minimization of condensation and fog on the exterior windows.  
         [0065]    With reference to FIG. 12, there is illustrated an interactive control module  260  for a transit mixer apparatus weight system. The transit mixer interactive control module  260  has been configured such that by the pressing of a switch will enable the operator to determine parameters associated with the weight of the the concrete and the load on the respective axles of the vehicle.  
         [0066]    More particularly, the specific parameters include a first interactive point for the front weight which gives the driver the tare weight of the front axle only plus an accumulative total of any additional weight that may be added to the front axle as the truck is loaded. A pair of second interactive point gives the driver the tandem weight which translates to the tare weight of the rear axles only plus an accumulative total of any additional weight that may be added to the rear axle as the truck is loaded. In one form of the present invention the weight for each tandem axle is provided separatly, in an alternative form of the present invention the interactive control module combines the weight of the tandem axles for reporting to the operator. Total weight gives the vehicles total tare weight plus an accumulative total of any additional weight that may be added to the vehicle as the truck is loaded. By pushing the pusher and tag interactive points the driver obtains the total weight on each of the auxiliary axles. Pushing the slump interactive point gives the driver a readout of the slump of the concrete to the nearest one half inch plus the operating pressure of the transit mixers hydraulic system. Further, the operator has the capability to push an interactive point to obtain the total gallons of water that has been added to this particular load of concrete. Furthermore, an additional interactive point gives the driver a read out of both the weight and total cubic yards of payload carried in the mixing barrel.  
         [0067]    With reference to FIG. 13, there is illustrated a schematic of the load sensing portion of the total weight system for the front discharge transmit mixer apparatus  10 . Associated with each wheel is a pressure transducer  265  for sensing and communicating the air pressure in the air springs associated with each wheel. The pressure data from each wheel is fed via a communication pathway to a central processor  266  locator within the operator cab  30 , and the data is interpreted by the central processor  266  so that the operator can interact with the processor  266  through control module  260 . The analyzed data provided from the interactive control module  260  will enable the operator to determine the load at each axle, and adjust the air pressure accordingly in the air springs so as to distribute the load and comply with government highway and bridge loading regulations. The capability of being able to monitor the load on each axle will assist the operator in adjusting the axle loading so as to comply with government regulations associated with road and bridge loading.  
         [0068]    With reference to FIG. 14, there is illustrated a side elevational view of the transit mixer apparatus  10  as previously set forth in FIG. 1 having the mixing apparatus control unit  181  operated at a location remote from the operator cab. In one form of the present invention the mixing apparatus control unit  181  is coupled to the apparatus  10  by a flexible cord. Other systems for remote communication are contemplated herein including radio transmission. Further, in another embodiment of the present invention a second mixing apparatus control unit  181  is mounted to an exterior location on the transit mixer  10 . The exteriorly mounted mixing apparatus unit  181  is positioned proximate the front end of the apparatus  10  to enable the operator to control the necessary functions of the chute and discharge/charge system.  
         [0069]    With reference to FIGS. 15 and 15 a , there are illustrated enlarged views of the mixing apparatus control unit  181 . The mixing apparatus control  181  integrates the chute control  510  and the discharge and charging control  511  of the barrel into one microprocessor controled system. The chute control  510  is an electronic joy stick that is utilized to control the hydraulic cylinders for simultanous movement of the front discharge chute inasimuth and elevation. The discharge and charge control  511  allows the operator to select a speed which will subsequently be maintained at a constant speed independently of the engine speed. In another form of the present invention the microprocessor has preprogrammed speeds that are selected by the operator for charging and/or discharging. The ability to maintain a constant speed independent of the engine speed results in a reduction in barrel wear, and enables the charging of the barrel at an optimized flow rate without overflowing. Further, the electronic control allows the driver to select to discharge concrete from the barrel at a pre-programmed speed in revolutions per minute. The mixing apparatus control unit  181  provides the operator with data related to the barrel revolutions. The data available to the operator includes mixing revolutions and the total revolutions of the mixing barrel.  
         [0070]    With reference to FIG. 16, there is illustrated a side elevational view of another embodiment of the transit mixer apparatus. Transit mixer apparatus  310  is substantially identical to the transit mixer apparatus  10  and hereinafter like figure numbers will represent like features in the FIG. 16 and FIG. 1. The mixing barrel  340  has been manufactured to a different length than mixing barrel  40 , with the difference in length being designed to change the weight distribution loading on the chassis. The front support  42  for barrel  340  has not changed, and the rear mount  43  is identical with the exception that is has been moved to a new location on mounting rails  311  (FIG. 5). In this example the rear mount  43  has been slid forward on rails  311  to move the back end  340   a  of mixing drum  340  forward. The shifting of the rear mount  43  is accomplished by sliding the rear mount  43  on the mounting rails  311  and locking the rear mount  43  in the new location. In the preferred embodiment, the locking of the rear mount  43  to the mounting rails  311  is accomplished by moving fasteners into a different aperture in the rails  311 . The changing of the position of the rear mount  43  will cause a change to the weight distribution of the plurality of axles.  
         [0071]    With reference to FIGS.  1 - 16 , an example of the distribution of concrete to multiple locations will be set forth. The operator has the capability through the interactive control module to obtain the weight of the apparatus  10  and any concrete associated therewith. From this reference point the operator can discharge a quantity of concrete at a first job site, and then utilize the interactive control module  260  to calculate the new weight of the apparatus  10 . The difference in weight translates to a volume of concrete that was delivered to the first job site. Proceeding to the second job site the operator can continue to discharge concrete at each location, and have an accurate record of the quantity of concrete delivered. From this information the proprietor of the concrete delivery service/batch plant can invoice the respective customers. Further, an onboard printer is utilized in one embodiment to print billing tickets for the customer.  
         [0072]    While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only the preferred embodiment has been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected.