Patent Publication Number: US-2007119972-A1

Title: Device for spraying a fluid and a brush cutter provided with said device

Description:
FIELD OF THE INVENTION  
      The invention relates to a device for spraying fluid, especially fluid products that can be pumped for the treatment of plants and/or trees and/or stumps and more particularly liquid chemical products usable at this ends. The invention also relates to a brush cutter provided with such a device. The use of a device and a brush cutter by a same user allow a substantial improvement in the efficiency of workers.  
     DESCRIPTION OF THE PRIOR ART  
      It is known in the art to use sprayers to applied sprays of treatments fluids to plants and/or trees and/or stumps of trees. Such sprayers are well known and some are wearable by the user. Said sprayers may be divided into several classes including those of the type provided with a pressurized tank and those of the type provided with a reservoir having pumping means. It is also known in the art to associate pressurized or gravitational sprayers with brush cutter for punctual treatment of stumps.  
      However, existing devices or brush cutters provided with such devices are either heavy due to the pressurized tank or inefficient. Furthermore, existing devices show leaks problems (i.e. dripping of fluids at the nozzle) or necessitate the operation of a trigger valve to activate spraying of fluid at the nozzle. Leaks problems are important when the device is mounted on a brush cutter because vibrations of said cutter in use. Weight problems associated with combination of brush cutters and spraying device involve that workers are bothered in their movements and this may lead to a substantial increase of risks of accidents and possible damage to the environment (example: accidental release or dripping of phytocides).  
      The applicant has now discovered that it is possible to make light the spraying device that is substantially leak proof even when subjected to high vibrations. Advantageously, the problem of leaks of treatment fluids may be solved with an original valve that is opened only when the pumping means is started and prevent fluid leaks when the pumping means is stopped.  
      Advantageously, the device according to the invention may comprise a reservoir made of synthetic material, such as plastic material, and pumping means in fluid communication with said reservoir. Preferably, the device may be worn on the back of the user. Pumping means are preferably a mini-pump operated by a small electric motor (e.g. a direct current electric motor). More preferably, the pumping means may be a small submersible pump operated by a DC electric motor that is sealed into a plastic capsule to work in the fluid. According to the invention there is no need to pressurize the reservoir.  
     SUMMARY OF THE INVENTION  
      More particularly the present invention relates to a device for spraying a fluid, said device comprising: 
          a reservoir for the fluid to be sprayed;     pumping means comprising a electric motor operated pump having an inlet port in fluid communication with the fluid of said reservoir and an outlet port;     a tubing having opposite ends, one end being in fluid communication with the outlet port of the pump, the other end being in fluid communication with a spraying nozzle;     electric power supply means;     switch means, especially a on-off switch means;     electrical wiring connecting the electric power supply means, the electric motor and the switch means to have the electric motor remotely operated by said switch;     a harness means allowing a user to wear an assembly defined by the reservoir, the pumping means and the power supply means; and     a valve means provided across the tubing to allow passage of said fluid when this latter is pressurized by the pump and to prevent said fluid to drip from the nozzle when not pressurized by the pump.        

      Advantageously, a first fixing means is provided for fixing the nozzle and at least a portion of the tubing to a frame of a brush cutter of the type further comprising a working head, a motor, handles and a driving shaft connecting said motor to the working head, said portion of tubing being fixed to said frame to have said nozzle positioned in the vicinity of said working head; and wherein a second fixing means is provided for fixing the switch to a handle of said brush cutter.  
      Advantageously, the valve means comprises 
          a sleeve having opposite ends, an inner surface and an outer surface;     a ball;     a spring, preferably a compression spring, having opposite ends;     a first tubular member having opposite ends, one end thereof being provided with a vibration absorbing material and defining a seat for the ball while the opposite end is provided with means for engagement with one end of the spring;     a second tubular member having opposite ends, one end thereof being provided with an outer surface that contacts the inner face of the sleeve, while the opposite end is provided with means for engagement with the other end of the spring;     a third tubular member having opposite ends and an outer surface, one end of said third tubular member defining a seat for the ball; and     a sealing means contacting the outer surface of the third member and the inner surface of the sleeve, said sealing means further having vibration absorbing properties;        

      the third tubular member being at such a distance from the first tubular member that the spring pushes the ball against the seat of the third tubular member, said ball and the second tubular member being movable between two extreme positions, one with the ball pressed by the spring against both ball seats and to prevent the fluid to flow through said valve and prevent possible dripping of the fluid at the nozzle (when the pumping means are stopped) and another position with the ball held away the ball seat of the third tubular member under the action of the fluid pressurized by the pumping means to have the fluid flowing under pressure through the valve toward the nozzle. Of course, the sleeve has an inlet end and an outlet end. The inlet end is oriented toward the pumping means while the outlet end is oriented toward the nozzle.  
      Advantageously, the valve means is further mounted across the hose that is in fluid communication with the outlet port of the pump and the nozzle. Preferably, the sleeve may be completely inserted within the hose. In this case, the outer surface of the sleeve engages (by friction) the inner surface of the tubing. This frictional engagement is sufficient to held the valve in place in the tubing. Alternatively, the hose may be cut in two parts and the sleeve may be inserted in each ends to connect the hose parts together.  
      Advantageously, the sleeve may be made of a rigid plastic material; the seal may be made of a rubber like material, the ball and the tubular members may be made of plastic material. Of course, any appropriate material may be used. A particularly preferred material may be polypropylene. Preferably, it is resistant to fluids commonly used for the treatment of plants, trees and stumps. Alternatively, the valve means may be made of stainless steel. The spring is preferably made of stainless steel. However, any other appropriate material can be used.  
      Advantageously, the tubing is made of a first section and a second section, one end of the first section being connected to one end of the second section by a conventional hose connector; and the electrical wiring is provided with an electrical connector to allow the user to reversibly separate the assembly defined by the reservoir, the pumping means and the supply means from the brush cutter. Alternatively, the electrical connection may make an integral part of the hose connection.  
      Advantageously, the conventional hose connector is a conventional two parts quick plug for pressurized hoses; and the conventional wires connector is a conventional two parts electrical plug. Preferably, the two parts quick plug may be the one made of nylon and sold by the company MERCURY®.  
      Advantageously, the inlet port of said pump may be positioned inside the reservoir. Preferably, said pump may be an electric motor operated submersible pump.  
      Advantageously, the harness means comprise a conventional backpack, the reservoir being housed within a main pouch of said backpack; and wherein an opening is provided in said pouch to allow the passage of the tubing and electrical wiring.  
      The invention also relates to a brush cutter of the type comprising a frame provided with a working head, a motor, handles and a driving shaft connecting said motor to the working head, wherein a portion of the tubing of a device as defined hereinbefore is fixed to said frame with fastening means to have the nozzle positioned in the vicinity of said working head; and a switch, preferably an on-off switch, is fixed to a handle of said brush cutter with fastening means preferably to make easily reachable said switch by the user wearing a harness to which is attached the remain of the device.  
      Advantageously, the fastening means are conventional mechanical clips or fasteners. Of course, any conventional clips or fasteners may be used. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      Particularly preferred embodiments of the invention will be described hereinafter with reference to the following drawings:  
       FIG. 1  is a rear perspective view of the device according to the invention with the hose connected to a spraying tubular wand provided with a spray nozzle.  
       FIG. 2  is a rear perspective view of a brush cutter and a device where the spraying tubular wand is mounted on the frame, an on-off switch is mounted to one handle of said brush cutter; and connectors are provided for electric wiring and hose.  
       FIG. 3  is a partial cross sectional view of the tube with the male portion of a conventional quick plug for pressurized hose.  
       FIG. 4  is a cross sectional view of the valve of  FIG. 3  according to IV-IV, in closed position.  
       FIG. 5  is a cross sectional view of the valve according to the invention in opened position. Represented is an optional mounting of the valve in the hose  15 .  
       FIG. 6  is a rear view of the reservoir.  
       FIG. 7  is a cross sectional view of the reservoir.  
       FIG. 8  is a partial perspective view showing the connection of the hose to a tubular wand.  
       FIG. 9  is a cross sectional view of the connection illustrated in  FIG. 8 .  
       FIG. 10  is a partial view of a handle of the brush cutter equipped with a on-off switch. 
    
    
     DETAILED DESCRIPTION OF PARTICULARLY PREFERRED EMBODIMENTS  
      As illustrated in  FIGS. 1, 2 ,  6  and  7 , the spraying device  1  comprises: 
          a packsack  2 ;     a reservoir  3  provided with a capacity  5  for the fluid to be sprayed;     pumping means  7  comprising a electric motor  8  operating a pump  9  having an inlet port  11  in fluid communication with the fluid of said reservoir  3  and an outlet port  13 ;     a tubing  15  having opposite ends, one end being in fluid communication with the outlet port  13  of the pump, the other end being in fluid communication with a spraying nozzle  17 ;     electric power supply means  19 ;     a on-off switch means  21 ;     electrical wiring  23  connecting the electric power supply means  19 , the electric motor  8  and the on-off switch means  23  to have the electric motor  8  remotely operated by the on-off switch  23 ;     a harness means  25  allowing a user to wear an assembly defined by the reservoir  3 , the pumping means  7  and the power supply means  19 ; and     a valve means  27  which is provided across the tubing  15  between the outlet port  13  of the pump  9  and the spraying nozzle  17  to allow passage of said fluid when pressurized by the pump  9  and prevent the fluid to drip off the nozzle  17  when not pressurized by the pump  9 . Preferably, the nozzle  17  may be mounted on a tubular wand  18  that is advantageously provided with a bent portion  18   a.          

      Preferably, a first fixing means  100  is provided for fixing the nozzle and at least a portion of the tubing to a frame F of a cutter BC of the type further comprising a working head WH, a motor M, handles H and a driving shaft DS connecting said motor to the working head, said portion of tubing being fixed to said frame to have saif nozzle  17  positioned in the vicinity of said working head WH; and wherein a second fixing means  110  is provided for fixing the on-off switch to a handle H of said brush cutter BC. The invention also relates to the particularly preferred combination.  
      More particularly, the valve means  27  comprises 
          a sleeve  29  having opposite ends, an inner surface  31  and an outer surface  33 ;     a ball  35 ;     a first tubular member  37  having opposite ends, one end thereof being provided with a vibration absorbing material  39  (preferably a “O” ring made of an elastomeric material such as a synthetic or natural rubber) and defining a seat  41  for the ball  35  while the opposite end defines a housing  43  provided with at least one inwardly projecting stopper  45 ;     a second tubular member  47  having opposite ends, one end thereof being provided with an outer surface  49  that contacts the inner face  31  of the sleeve  29 , while the opposite defines a housing  51  provided with at least one inwardly projecting stopper  53 ;     a compression spring  55  having opposite ends, one end contacting the stopper  45  of the first tubular member  37  while the opposite end contacts the stopper  53  of the second tubular member  47 ;     a third tubular member  57  having opposite ends and an outer surface  59 , one end of said third tubular member  57  defining a seat  61  for the ball  35 ; and     a sealing means  63  contacting the outer surface  59  of the third member  57  and the inner surface  31  of the sleeve  29 , said sealing means  63  further having vibration absorbing properties (preferably a “O” ring made of an elastomeric material such as a synthetic or natural rubber);        

      the third tubular member  57  being at such a distance from the first tubular member  37  that the spring  55  pushes the ball  35  against the seat  61  of the third tubular member  57 , said ball  35  and the second tubular member  45  being movable between two extreme positions, one with the ball  35  pressed by the spring  55  against both ball seats  41 ,  61  to prevent the fluid to flow through said valve and to prevent dripping of the fluid at the nozzle  17  (when the pumping means are stopped) and another position with the ball  35  held away from the seat  61  of the third tubular member under the action of the fluid pressurized by the pumping means to have the fluid flowing under pressure through the valve toward the nozzle  17 . Advantageously, the fluid follows the arrows illustrated in  FIG. 5 .  
      More particularly, the reservoir and the constitutive parts of the device are made of plastic material that are resistant to liquid chemical products generally used in the treatment of plants, trees and/or stumps, such as phytocides, herbicides and all other similar products, especially those having a small viscosity. Preferred plastic material may be polypropylene. Alternatively, plastic material may be replaced by any other appropriate material such as stainless steel.  
      According to a particularly preferred embodiment, the reservoir may have a capacity of 4.5 litres, the harness means may be defined, as illustrated in  FIG. 1 , by a conventional backpack  2  provided with an usual main pouch, straps and belts to be comfortably wear on the back of a user. A small opening  67  may be provided on the side of the backpack to allow passage of tubing  15  and wires  23 . Advantageously, the backpack is made with a fabric that is water resistant and of course weather resistant. Preferably, said backpack  2  may have adjustable straps provided with adjustment buckles  66  and fasteners  68  (well known in the field of backpacks). Characteristics of the straps, adjustment buckles and fasteners are well known and do not necessitate any detailed description.  
      According to a particularly preferred embodiment of the invention, the power supply  19  means is portable and may consist of dry cells, especially rechargeable dry cells. Advantageously, a rechargeable 12 volts dry cell may be used. Preferably the cell may be recharged up to 500 times and have a weight of about 4.20 pounds.  
      Advantageously, the tubing  15  is made of a first section  15   a  and a second section  15   b , one end of the first section being connected to one end of the second section by a conventional hose connector HC; and the electrical wiring is provided with an electrical connector EC to allow user to reversibly separate the assembly defined by the reservoir, the pumping means and the supply means from the brush cutter BC. Advantageously, the conventional hose connector is a conventional two parts quick plug for pressurized hoses; and the conventional wires connector is a conventional two parts electrical plug. Optionally, filtering means FT may be provided.  
      Optionally, a fuse may be provided across the electric circuit to protect the motor. Advantageously, the wiring may comprise at least two electric wires and optionally three electric wires.  
      Optionally, as illustrated in the drawings, the reservoir may be provided with a first opening  69  for filling the reservoir  3 . This opening  69  may be closable by a cork  71 . Preferably, the cork  71  may be provided with thread engaging corresponding thread in the opening to have the cork  71  reversibly screwed in the opening  69 . Advantageously, the opening  69  and the cork  71  have a 4 inches diameter.  
      Optionally, as illustrated in the drawings, the reservoir may be provided with a second opening  73  for allowing to empty the reservoir  3 . This opening  73  may be closable by a cork  75 . Preferably, the cork  73  may be provided with thread engaging corresponding thread in the opening to have the cork  75  reversibly screwed in the opening  73 . Advantageously, the opening  73  and the cork  75  have a 4 inches diameter.  
      Preferably, the pumping means comprise a sealed electric motor  8  connected to a submersible pump  9  having an inlet port  11  and an outlet port  13 , the outlet port  13  being in fluid communication with a tubing  13   a  passing through the wall of the reservoir  3  and having a free end provided with the female part of a two part quick plug for pressurized hoses. The tubing  13   a  may be soldered to the wall of the reservoir  3 . Alternatively, any appropriate sealing means (e.g. a sealant) may be used to prevent fluid leaks. The female part of said quick plug is generally provided with a check valve means preventing drainage of the content of the reservoir when the male part is not engaged therein. Those quick plug are well known in the art and do not need any extensive description. Alternatively, the outlet port may consist of a 7 mm tubing on which the 8 mm tubing is coaxially mounted. Frictional engagement between saids 7 mm and 8 mm tubings is sufficient to make a tight and solid connection.  
      The pumping means and electric motor, as illustrated in  FIG. 7 , are held in place within the reservoir by a pair of support members  77 . Preferably, one of said support members  77  are respectively positioned at 1.25 inch and 2.5 inches from the bottom of the reservoir and the outlet port of the pump is positioned at 1 inch of the bottom of the reservoir. Preferably, the inlet port of the pump may be optionally provided with filtering means (not illustrated). The electric motor is preferably encapsulated in a water tight hard shell made of plastic material to allow it use within the fluid.  
      Neoprene washers  79  allows the wires to pass through the wall of the reservoir  3 . More particularly, for each wire a bolt  81  pass through the wall. An electric wire is connected on both side of the wall and then held in place by a nut  83 . Washers  79  may be positioned against both sides of the wall.  
      Preferably, the electric wires comprise two wires, a negative and a positive. They follow the side of the reservoir; the positive wire connects the motor  8  and the cell  19 . Two negative wires respectively connect the cell  19  and the on-off switch  21  and the electric motor  8  and the on-off switch  21 . The on-off switch  21  may be of any appropriate kind, including the trigger type or press button type. Preferably, the on-off switch is of the press button type. More particularly, as illustrated in  FIG. 9 , the on-off switch is mounted by means of nut-bolt assembly  85  cooperating with the handle H of the brush cutter BC. Any other appropriate on-off switch may be fastened to the handle of the brush cutter by any appropriate means such as mechanical clips, tie-wrap, etc.  
      Alternatively, the cell  19  may be worn by the user thanks to a harness including a belt of the user or including a specific belt wear at the waist of the user.  
      Advantageously, the tubing  15  may be made of flexible material, especially a 8 mm diameter flexible plastic tubing.  
      Advantageously, the nozzle is of the type well known in the art, especially a nozzle of Chapin type that may be screwed at one end of a tubular wand  18  (rigid tubular conduit having a portion  18   a  that is angularly bent). Such wand and nozzle are well known in the art and do no need any detailed description. Preferably, the nozzle  17  may be made of brass.  
      In use, when the device  1  has a part thereof mounted on the frame of the brush cutter BC, the user may spray a treatment liquid on a punctual area to be treated (example a stumps of brushes he just finished to cut) by mere pressure of the press button with the thumb of his hand on the left handle of the brush cutter. When he press said button, the pump  9  is activated by the motor  8  and the pressure generated moves the ball  35  away from the seat  61  and allow the fluid to flow through said valve and then sprayed while exiting the nozzle  17 . When he release the button, the pump stops and the spring  45  returns the ball against the seat  61  to prevent the fluid to pass the valve and prevent the fluid to drip from the nozzle  17 . When the user wants to leave, he may disconnect the hose connector HC and the electric connector EC and leave the brush cutter BC on the premise. Later, he can reconnect said connectors and continue his work  
      Of course, the above description of the embodiments of the invention is not limitative and also comprises all possible variations and embodiments that may seems obvious to a man skilled in the art.