Abstract:
This invention relates generally to a lightweight dolly for transporting spray equipment including a container of liquid, battery power pack and optional charger unit, hose reel, and spray gun.

Description:
This application claims priority from U.S. Provisional Patent Application Ser. No. 60/116,190 filed on Jan. 15, 1999, incorporated by reference herein. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Technical Field 
     This invention relates generally to a lightweight dolly for transporting spray equipment including a container of liquid, battery power pack and optional charger unit, hose reel, and spray gun. 
     2. Summary of the Invention 
     The instant invention is used for applying chemicals, detergents, and sealers to decks, houses, driveways, fleet vehicles, and the like. 
     The handle and frame are constructed of hollow PVC tubing reinforced with steel. The top plate, gussets, pump box, battery box, and bucket holder are constructed of high density plastic which is welded together with PVC weld. The components are heated, bent and placed into a wooden mold and formed into shape and then cooled. 
     The instant invention has ten inch pneumatic wheels with a front locking swivel caster that allows for easy maneuvering in rocks and grass. The hose reel is retractable and is connected to a chemical resistant pump. The pump can run AC or DC with the battery charging system that requires a battery, preferably a marine battery, or it can be plugged into an outlet. Moreover a retractable electric cord may be mounted to the frame as well. The spray gun is light weight, and is attached to a 12 inch aluminum lance and an adjustable cone nozzle. This special nozzle allows the user to change the flow rate of the product that is being applied for a particular application. The entire unit of the preferred embodiment weights only 32 pounds. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A better understanding of the present invention will be had upon reference to the following description in conjunction with the accompanying drawings in which like numerals refer to like parts throughout the several views and wherein: 
     FIG. 1 is a left side view of the present invention; 
     FIG. 2 is a rear end view thereof; 
     FIG. 3 is a front end view thereof; 
     FIG. 4 is a right side view thereof; 
     FIG. 5 is a top plan view thereof; 
     FIG. 6 is a bottom plan view thereof; 
     FIG. 7 is a plan view showing the motor and pump of the present invention; 
     FIG. 8 is a side view showing the handle of the spray gun of the present invention; 
     FIG. 9 is a perspective side view of another embodiment of the present invention; 
     FIG. 10 is a schematic of the transformer charging system and AC/DC switch for the present invention; 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The present invention is fabricated from lightweight plastic materials; however it is contemplated that one or more structural frame support members may be molded or formed integrally to reduce the number of frame members. Moreover, the frame members may be fabricated with removable snaps, projections and insertion points to provide for easy and quick assembly by the user whereby the individual parts fit into cooperative engagement with one another. 
     One preferred embodiment of the present invention comprises a spray dolly  1  as shown best in FIGS. 1-7 having a movable base and frame handle, wherein the base is generally rectangular tubular base frame  20  composed of plastic pipe or tubing joined together forming front  21  and side longitudinal members  22  supported by pneumatic tires  10  and wheels via an steel axle  13  as shown best in FIG. 8 extending normal to and through the rear length  24  of base frame  20  tubing. The frame and handle are preferably high density steel reinforced plastic to provide chemical resistance to corrosion. A pair of ninety degree elbows  26  made of plastic join the distal ends of the horizontal side longitudinal members  22  with the distal ends of a pair of vertical longitudinal members  28  formed of plastic pipe or tubing. At about waist level of the user, the tubes are bent at a slight angle forming elbows  30  extending backward toward the user at an obtuse angle of about 130 degrees wherein a short pair of angled tubular members  32  extend outwardly toward the user. A horizontal tubular member  34  joints the distal ends of the short angled tubular members  32  forming a handle spaced apart and extending outward a selected distance from the rear of the frame  20 . 
     The preferred plastic is ABS, (acrylonitrile butydiene styrene); however, polypropylene, graphite fiber, nylon, polyvinylchoride or other polymers could be utilized for fabrication of the structural members to maximize corrosion resistance to the chemical applications. 
     In the preferred embodiment reinforcement support plates  36  extend from the bottom portion of the vertical longitudinal members  28  to join the upper surface of the base frame side members  22 . A length of straight pipe may be inserted into the horizontal side members  22  and/or the vertical side members  28  to add structural rigidity to the frame; however, this is not a required feature of the structure. Moreover, the lengths of pipe could be joined at the elbow. 
     A flat sheet  11  of material is attached to the upper surface of the frame base members  21 ,  22  forming a base support surface. At least one swivel dolly wheel  12  is attached to the underneath surface of the base  20 . The swivel dolly  12  of the preferred embodiment includes a stop means such as a lever to bias the wheel  12  in locked or unlocked position permitting rotational movement thereof. 
     A novel feature of the preferred embodiment is the formation of a circular lip container or bucket support  15  extending upward from the front portion of the frame base support sheet  11  to hold a five gallon bucket of spray solution. The bucket  2  is securely held in the sprayer base  11  providing a mobil unit which enables the user to switch buckets rapidly or remove the bucket for changeover, cleanup, or other preparations. A retractable hose reel  3  such as shown in FIGS. 1-8 and described in detailed exploded view in FIGS. 9-11. A manual crank hose reel may also be employed in the instant invention as well. The hose reel is fabricated from 11 gauge steel supports and utilizes self aligning bearings on both sides. The hose can be comprised of any polymer; however, VITON is preferred due to its chemical resistance and ability to withstand pressures up to 150 psig. An extra hose support  70  may be attached to the rear of the frame. 
     One end  23  of hose  37  from the reel is connected to the discharge end of a pump of an electric motor and pump assembly such as set forth and described in FIGS. 14-15 providing a selected pressure of from about 60 to 100 psig. of solution The free end  25  of the hose  37  extending from the suction end of the pump as shown best in FIGS. 1 and 3 is bucket of spry solution. While separate motor and pump assemblies can be supplied to run off of AC or DC current, the preferred embodiment utilizes a single motor and pump with a switching device to switch from AC to DC current in order to minimize weight of the unit. The motor  29 , pump  52 , transformer such as incorporated within a conventional battery charger  50 , and AC/DC switch as best shown in FIGS. 11 and 13, are held in a water proof control unit case  38  attached to a plate  40  extending between the upper portions of the vertical longitudinal members  28 . The pump is a demand pump activated by a simple toggle switch. The other end  42  of the hose  37  extending from the pump discharge is fed into the hose reel  3 . The free distal end  27  of the hose  43  extending from the reel  3  is fitted with a quick disconnect coupling  44  which is cooperatively engagable with a mating quick disconnect coupling  45  extending from the handle  47  of the trigger spray gun  46  as described in detail in FIG.  12 . An adjustable cone, flat spread pattern, fan tip, or zero degree focused pin point spray nozzles are removably attached to the end of the coupling to product a fine mist, straight stream or variations thereinbetween. The pump will pump up to 150 pounds, preferably the range of from 60 to 100 psig is used to pump cleaners, detergents, sealers, caustic or acid solutions depending upon the application. Flow rates up to 2.0 gallons per minute, and typically from 0.1 to 1.6 gallons per minutes are usual for cleaners and sealers. The sprayer will spray up to 50 feet depending on the environmental conditions; however, 30 feet is typical for applications involving building, gutter, and roof cleaning applications. 
     The electric pump motor is either  110 - 115  AC or 12 volt DC operation; however, a 220 Volt motor can be employed with the unit. A battery charger unit  50  such as shown in FIG. 1 in phantom lines and on the embodiment illustrated in FIG. 9 may be employed with the unit to connect with and recharge the battery  31  as needed for use in the DC operation. The unit&#39;s battery can be charged while in use in the DC mode by plugging in the charger to a 110 or 115 volt electric outlet. The charger includes a manual control where the use cuts off the charger and an automatic mode wherein the charger cuts off the AC current upon the battery reaching a preset full charge. The preferred embodiment utilizes a 10 amp fast charge with automatic shutoff. 
     The pump is a positive displacement three chamber diaphragm pump using a 2-way check valve preventing reverse flow and up to six foot head forward flow. It utilizes a 3 degree cam and permanent magnets. A pressure switch having an adjustable shut off ranging from 80 to 100 psi is utilized with the preferred embodiment. The pump is self priming and can pump solutions up to 180° F. 
     The operation of the control unit consists of an “off” mode wherein the sprayer unit is idle; a charger mode wherein the battery is charged at a dual stage utilizing a high charge rate when being used and a trickle charge at rest, in AC operation the motor is operating from the transformer through a circuit which switches the AC current to DC current; and in the battery operating mode the motor is operating from the battery. Of course, the battery can be charged while in use if desired. 
     FIGS. 10 shows an alternate embodiment of a sprayer dolly unit  100  in accordance with the present invention wherein the frame is made of metal tubing and sheet metal. 
     The foregoing detailed description is given primarily for clearness of understanding and no unnecessary limitations are to be understood therefrom, for modification will become obvious to those skilled in the art upon reading this disclosure and may be made upon departing from the spirit of the invention and scope of the appended claims. Accordingly, this invention is not intended to be limited by the specific exemplifications presented hereinabove. Rather, what is intended to be covered is within the spirit and scope of the appended claims.