Abstract:
Draining of the waste tank of a recreational vehicle is improved by using a motor to operate the waste hose. The motor causes the proximal end of the hose to be extended from its housing in the RV while the distal end remains attached to the waste tan. The extended proximal end can then be inserted into the access pipe of a sewer system for draining the waste tank. The motor will retract the hose when the waste tank has been emptied. The motor is operable either by throwing a switch on the motor or pressing a button on a remote control unit.

Description:
PRIORITY CLAIM  
       [0001]    The applicant claims the benefit of the filing of US provisional application Ser. No. 60/257,409 filed 12/22/2000, which is incorporated herein by reference. 
     
    
     
       FIELD OF THE INVENTION  
         [0002]    The present invention relates generally to the operation of the living quarters of recreational vehicles. More particularly, it relates to the expunging of the waste tank of the recreational vehicle.  
         BACKGROUND OF THE INVENTION  
         [0003]    There are a many different types of recreational vehicles, often referred to as “RVs”. One type of RV has living quarters that include a toilet, washing and kitchen facilities. The waste products from these are collected in an on-board tank that must be periodically expunged.  
           [0004]    The process for expunging the waste tank is relatively straight forward. The RV must stop next to a sewer system access pipe, commonly found at RV parks, where the operator of the RV connects the waste tank via a hose to the access pipe. Then, a valve is opened to allow the waste from the tank to drain by gravity into the sewer system.  
           [0005]    The hose is connected permanently to the RV waste tank and stored in a compartment toward the back of the vehicle. The hose is expandable that can be compressed to fit within its compartment, usually in the bumper, or stretched so that it can be inserted into the sewer system.  
           [0006]    This operation may be straightforward, but it is also a disagreeable task. RV&#39;s are designed to allow relatively convenient draining of its waste tank and sewer system access pipes are available at convenient locations for RV travelers, but ultimately, the operator of the RV must still undertake the chore of draining the tank. Furthermore, the end of the hose becomes fouled with waste. Odors add to the disagreeable nature of the task.  
           [0007]    Thus, there remains a need for improvements in the way the waste tank of an RV is emptied to lessen the disagreeable aspects of this chore.  
         SUMMARY OF THE INVENTION  
         [0008]    According to its major aspects and briefly recited, the present invention is a motorized device to extend and retract the waste hose of an RV. The motorized device causes the proximal end of the hose to be extended from the RV so that it can be inserted into the access pipe of a sewer system and will retract it when the waste tank has been emptied. The device is operable either by throwing a switch to activate a motor or pressing a button on a remote control unit.  
           [0009]    The use of a motor is an important feature of the present invention. The use of a motor obviates the need to physically pull the hose from its compartment and to push it back into the compartment, which are both disagreeable tasks.  
           [0010]    The operation of the motor using a remote control is another feature of the present invention. The use of the remote also allows the RV operator conduct the procedure in part without having to go to a fixed set of controls.  
           [0011]    These and other features and their advantages will be apparent to those skilled in the art of RV usage and design from a careful reading of the Detailed Description of Preferred Embodiments, accompanied by the following drawings. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0012]    In the drawings,  
         [0013]    [0013]FIG. 1 is a perspective view of an RV with the waste hose connected to the access pipe of a sewer system;  
         [0014]    [0014]FIG. 2 is an end view and partial schematic view of the present motor according to a preferred embodiment of the present invention;  
         [0015]    [0015]FIG. 3 is a side view of the present motor and waste hose in the retracted position, according to a preferred embodiment of the present invention; and  
         [0016]    [0016]FIG. 4 is a side view of the present motor and waste hose in the extended position, according to a preferred embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0017]    The present invention is a motorized device for use in extending and retracting a waste hose of a recreational vehicle (referred to herein as an “RV”). The invention is also the combination of a motor, controls for the motor, a waste hose and an RV.  
         [0018]    The RV, whether part of the combination that is the invention or not, is one equipped with a waste tank that must periodically be drained. When it is drained, the waste from the waste tank is drained into a sewer system through an access pipe. The sewer system and access pipe, and the waste are of course not part of the present invention.  
         [0019]    Referring now to the figures, there is illustrated an RV, generally indicated by reference number  10 , having a waste hose  12  that can be inserted into a sewer system (not shown) via an access pipe  14 . A housing  16  carries waste hose  12 . Housing  16  preferably has a cover (not shown). For manipulation of the free end of the extended waste hose  12 , a gripper  18 , shown slightly enlarged in FIG. 1 for clarity, proves convenient.  
         [0020]    [0020]FIG. 1 shows the waste hose  12  mounted to a left, rear comer of RV  10  but it will be clear that waste hose  12  can exit RV  10  from other parts of RV  10 , including the sides and other areas of the back of RV  10 . The bumper of an RV can double as a compartment for hose  12 .  
         [0021]    RV  10  has a waste tank  20  and a pipe  22  leading from and in fluid communication with waste tank  20 . A valve  24  controls the flow of waste from waste tank  20  through pipe  22 . When valve  24  is opened, the waste drains by gravity from waste tank  20  through pipe  22 . When valve  24  is closed, no further waste may drain.  
         [0022]    Waste hose  12  has a distal end  30  that is coupled to pipe  22 , so that waste hose  12  is in fluid communication with waste tank  20 , and a proximal end  32  near the exit of housing  16 . Waste hose  12  is adapted to be stretched in length, preferably because of its ribbed or “accordian” or “corrugated” construction, as shown in FIGS. 3A and 3B, so that hose  12  can be moved between a retracted position and an extended position by moving proximal end  32  with respect to distal end  30 . By the term “extended”, then, it is meant that proximal end  32  is moved so that the distance between it at distal end  30  is increased but that distal end  30  and proximal end  32  remain in fluid communication. Importantly, waste tank  20  and proximal end  32  also remain in fluid communication via the coupling between waste hose  12  and pipe  22  at distal end  30  when waste hose  12  is extended.  
         [0023]    Inside housing  16  is means for extending waste hose  12 . Preferably, rollers  34  and  36  are used to push proximal end  32  from housing  16 , to the extended position from the retracted position, either mechanically or electro-mechanically thereby extending waste hose  12 . Rollers  34  and  36  are affixed to shafts  42  and  44 , respectively, which are mounted in bearings (not shown) carried by housing  16 .  
         [0024]    Shafts  42  and  44  are rotated using a system of gears  50  that accomplish several things. First, they rotate rollers  34  and  36  in opposing directions. As shown in FIGS. 3A and 3B, when rollers  34  rotate counter-clockwise, rollers  36  rotate clockwise so that waste hose  12  is extended. When rollers  34  rotate clockwise, rollers  36  rotate counter-clockwise so that waste hose  12  is retracted. Second, gear system  50  causes the rotation of gears  34  and  36  at the same rate so that waste hose  12  is extended and retracted straight out of housing  16 . Third, gear system  50  adjusts the rate at which waste hose  12  would otherwise be extended and retracted by a power source (to be described below) so that the extension and retraction takes place at a reasonable, controlled rate.  
         [0025]    The composition and arrangement of gears in gear system  50  that is needed to achieve the foregoing requirements is well within the level of skill of those skilled in the art and clearly depends on the choice of gears, the distance between shafts  42  and  44 , and the speed of a motor  60  driving the gears. However, there is preferably a driving gear  52  connected directly to motor  60 , one driven gear  54  for shaft  42 , one driven gear  56  for shaft  44  and one direction-reversing gear  58 . Additional gears may be needed to step down the speed of an output shaft  62  of motor  60  and possibly to connect driving gear  52  with driven gears  54  and  56 . Other arrangements are possible, such as using separate motors to drive shafts  42  and  44  and direct drive of one or both shafts  42  and  44 .  
         [0026]    Motor  60  is activated by a battery  66  of RV  10  via a switch  64 . Switch  64  can be located at housing  16  or inside RV. In lieu of motor  60 , a hand crank (not shown) can be easily substituted. Also, as an alternate to a switch  64  or in addition to switch  64 , a remote control unit  70  can be used to transmit a signal to a receiver  72  that operates switch  64 .  
         [0027]    Switch  64  is preferably a three-way switch as shown, with an “off” position, a “forward” position” and a “reverse” position. In the forward position, waste hose  12  is extended by motor  60 ; in the reverse position, waste hose  12  is retracted by motor  60 . Switch  64  may be switched to the off position when waste hose  12  has been retracted far enough or other features maybe incorporated to limit the rearward travel of waste hose  12 , such as limit switches (not shown) that would automatically stop motor  60  when waste hose  12  had returned fully to housing  16 . The maximum extension of waste hose  12  can be obtained when rollers  34  and  36  slip from their inability to further extend waste hose  12  or by incorporating an electrical contact that is closed when sufficient extension is obtained.  
         [0028]    In operation, an RV operator stops RV near access pipe  14 , closes switch  54  either manually by pressing a button or by using remote control unit  70  in electrical communication with a receiver  72 , which is in turn in electrical connection with battery  66  and switch  64 . Battery  66  energizes motor  60  which rotates output shaft  62 . Gear system  50  causes shafts  42  and  44  to rotate which in turn rotates rollers  34 ,  36 , respectively. Rollers  34 ,  36 , extend proximal end  32  of waste hose  12  from motor housing so that the operator can merely place proximal end  32  into access pipe  14  using gripper  18 . The valve  24  is opened and waste tank  20  drains by gravity. When waste tank  20  is drained, valve  24  is closed, gripper  18  is used to remove proximal end  32  of waste hose  12  from access pipe  14  and switch  64  is moved to the retract position. Motor  60  operates in reverse, based on reversal of its polarity and retracts waste hose  12 . Gear system  50  operates in reverse to draw proximal end  32  of waste hose  12  back toward motor housing  16 .  
         [0029]    It will be apparent to those skilled in the art of electro-mechanical motors that many substitutions and modifications can be made to the preferred embodiments described above without departing from the spirit and scope of the present invention, which is defined by the appended claim.