Abstract:
A wall compound applicator appliance that has a work station including a reservoir for containing a supply of wall compound, an air compressor, an applicator tool, a portable compressed air tank to operate the applicator tool, and a carrying strap assembly to attach the tank to a user with the tank connected to the applicator tool. The applicator tool has a cylindrical, tubular body to receive a supply of wall compound. The reservoir has a transport tube that is connectable to a one-way fill valve on the applicator tool to refill the applicator tool with wall compound. An adapter is connected to the work station and has a fitting to connect to a refill airline that is connected to the portable compressed air tank in order to refill the tank at the same time that the applicator tool is being refilled. Once the applicator tool and the compressed air tank are refilled, the workman is free to move about the work area independent of a work station and the air compressor.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
       [0001]    This application is a continuation-in-part of U.S. application Ser. No. 09/941,977 filed Aug. 29, 2001 which application claims the benefit of provisional application Serial No. 60/229,459, filed Sep. 1, 2000. 
     
    
     
       BACKGROUND OF THE INVENTION  
         [0002]    Drywall finish coating, or the application of joint compound to taped seams, is tedious when done manually. Drywall joint compound applicator tools are available to ease this task. Examples of such tools are shown in U.S. Pat. No. 5,863,146 to Denkins, et al. (Denkins I), issued Jan. 26, 1999 and in U.S. Pat. No. 5,878,925 to Denkins, et al. (Denkins II), issued Mar. 9, 1999, both of which are incorporated herein by reference. The Denkins I tool for applying joint compound has a hollow tubular storage body connected to a compressed air supply and a plunger longitudinally movable within the body. Joint compound fills the body. The compound is introduced into the tubular body through a one-way fill valve ahead of the plunger. Compressed air pushes the plunger forward to move the compound supply out through an applicator tip at a discharge end of the tool. The applicator tip retains any of a variety of attachment tools. A compressed air inlet fixture is at the opposite or air inlet end of the tube. An air compressor supplies pressurized air to the Denkins I storage body through the inlet fixture.  
           [0003]    The Denkins II appliance includes a tool for applying joint or drywall compound, such as that shown in Denkins I, along with a joint or drywall compound supply reservoir for holding a supply of compound. A pump moves the compound from the supply reservoir through the hollow tubular storage body of the applicator tool to refill the tool with compound. A compressed air manifold attaches to the supply reservoir and connects to an air compressor. An air line connects to the applicator tool to provide it. Compressed air serves as the motive force to move the compound through the tool body to the applicator tip. The manifold has a number of attachment ports to permit simultaneous attachment of a number of applicator tools.  
           [0004]    The air line connecting the applicator tool to the compressed air port on the supply reservoir can be problematic. The worker is tethered to and limited by the large stationary air compressor. This limits the mobility of the worker. The worker may become fatigued or entangled, attempting to move the heavy and cumbersome lines, the reservoir or the air compressor closer to a remote work site. When more than one tool is in use, there is a possibility of the lines becoming entwined or knotted.  
         SUMMARY OF THE INVENTION  
         [0005]    The invention relates to a novel joint or drywall compound applicator appliance having a workstation with a reservoir for containing the joint or drywall compound, an air compressor, an applicator tool, a portable compressed air tank to operate the applicator tool, and a carrying strap assembly to attach the tank to a user with the tank connected to the applicator tool. The applicator tool has a cylindrical, tubular body to receive a supply of wall compound. Compressed air from the compressed air tank operates the applicator tool. The applicator tool has a nozzle at a discharge end of the tube and a compressed air fitting at the air inlet end. The portable tank is held by a carrying strap assembly so that the worker can carry the tank and applicator tool from place to place to perform the joint or drywall finishing projects. The worker moves about free of constraints as might otherwise be imposed by dragging around an air supply line connected to air compressor. A novel adaptor of the invention is connected to the workstation and is used in one-stop refilling of the compressed air tank while the applicator tool is being refilled with compound. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0006]    [0006]FIG. 1 shows a commercial embodiment of a portable wall compound applicator appliance of the prior art;  
         [0007]    [0007]FIG. 2 shows in greater detail the applicator tool of the applicator appliance of FIG. 1;  
         [0008]    [0008]FIG. 3 shows a worker using the applicator appliance of FIG. 2 applying joint or drywall compound to a wall;  
         [0009]    [0009]FIG. 4 is a facing view of a worker holding an applicator appliance according to the present invention;  
         [0010]    [0010]FIG. 5 is a rear view of the worker and applicator appliance of FIG. 4;  
         [0011]    [0011]FIG. 6 is a plan view of the applicator tool assembly of the applicator appliance of the invention;  
         [0012]    [0012]FIG. 7 shows the applicator tool connected to the supply reservoir of the applicator appliance;  
         [0013]    [0013]FIG. 8 is a schematic view of the adaptor of the invention;  
         [0014]    [0014]FIG. 9 is a rear view of a workman carrying a compressed air tank of the applicator appliance of the invention using a carrying strap assembly according to a second embodiment of the invention;  
         [0015]    [0015]FIG. 10 is a plan view showing one side of the carrying strap assembly of FIG. 9; and  
         [0016]    [0016]FIG. 11 is a plan view of the other side of the carrying strap assembly of FIG. 10. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0017]    [0017]FIGS. 1 through 3 show prior art applicator equipment. FIG. 1 shows an applicator appliance that includes a workstation  10  having a joint or drywall compound canister or reservoir  11  mounted on a wheeled cart  12  having a handle  14 . A transport tube  15  connects through a pneumatically-driven suction-type diaphragm pump  16  to the bottom of the reservoir  11 . A fill attachment nozzle  17  is located at the top of the transport tube  15  connected near the top of reservoir  11 .  
         [0018]    A compressed air manifold  18  is connected to the workstation and has a plurality of pressure ports. The manifold  18  connects to an air compressor (not shown in FIGS.  1 - 3 ). An applicator tool or gun  19 , connectable to a pressure port, hangs for storage on the handle  14  of the cart  12 . FIG. 2 shows the conventional applicator tool  19  in greater detail. The applicator tool  19  has an elongate hollow barrel tube  20  with an applicator nozzle  21  at a discharge end of the tube  20 . A one-way fill valve  23  is between the tube  20  and the applicator nozzle  21 . The fill valve  23  opens to the interior of the tube  20  for filling the tube  20  with joint or drywall compound from the reservoir  11 . Fill valve  23  may be any of a variety of commercially available one-way fill valves, such as a poppet valve or a ball and seat valve. Fill valve connects to the fill attachment nozzle  17  on transport tube  15  for refilling applicator tool  19 . The applicator nozzle  21  can retain any of a variety of attachment tips such as those illustrated schematically in FIG. 1. An open/shut valve  26  is connected between nozzle  21  and tube  20 . Valve  26  is closed when tube  20  is being filled through one-way valve  23 , and is open during normal operation of the applicator tool  19 .  
         [0019]    The opposite or air inlet end of the tube  20  carries a compressed air fitting  22  for connection to a quick release pressure fitting on a compressed air line. A plunder assembly  37  is installed inside of the tube  20 . Compressed air moves the plunger to force compound contained in the tube  20  out of the applicator nozzle  21 .  
         [0020]    [0020]FIG. 3 shows a worker  24  holding the applicator tool  19  in the procedure of applying joint or drywall compound to a wall. An air line  25  connects the applicator tool  19  to one of the compressed air ports on the compressed air manifold  18 . The presence of the air line  25 , which may extend more than several feet from the reservoir  11  to the applicator tool  19 , limits and hinders the movement of the worker  24 . Typically, the work site encountered by a dry wall worker  24  is encumbered with a variety of objects that may easily entangle an air line  25  of such length. The air line  25  itself may become nicked and frayed from dragging across a crowded work site, requiring early replacement. The long air line  25  may entangle or pull over equipment requiring down time for clean up or even expensive repairs. The entangling air line  25  can endanger workers themselves. In actual use situations, entanglement of the air line  25  has led to breakage of vital components of the conventional applicator  19 , such as pressure relief valve  62 .  
         [0021]    [0021]FIGS. 4 and 5 show an applicator appliance according to the invention indicated generally at  31  having certain components in common with the prior art appliance as will be illustrated through the use of common reference characters. The applicator appliance includes a work station  10  as previously described, and an air compressor  32  connected to the manifold  18  by a compressed air output line  32 . Another worker  30  carries an applicator tool  19  powered by a small, lightweight portable, refillable air tank  36 . A first compressed air line  34  connects to the compressed air fitting  22  of the applicator tool  19 . The opposite end of the compressed air line  34  operatively connects to compressed air tank  36 . The worker  30  carries the tank  36  supported on his back and/or waist in an out-of-the-way location. Tank  36  is carried by means of a strap assembly  38 . A second compressed air line or refill air line  40  extends from the portable compressed air tank  36  for use in refilling the tank  36  as needed. Air line  40  can hang freely when not in use. Tank  36  provides compressed air to the tool  19  to move the plunger (indicated at  37  in FIG. 6) in body  20  to move compound through the nozzle as previously described. As shown in FIGS. 4 and 5 the worker  30  moves around and performs work independent of the location of the air compressor  32  or the workstation  10 , returning to the workstation  10  only periodically to refill the applicator tool  19  and the compressed air tank  36  at the same time.  
         [0022]    [0022]FIG. 6 shows in plan view the applicator tool  19  connected to air tank  36 . Applicator tool  19  carries a charge of wall compound  27 . The applicator tool  19  connects at the compressed air fitting  22  to the first compressed air line  34 . A T-fitting  35  is secured to the end opening of tank  36 . The refill air line  40  is connected at one end to one leg of the T-fitting  35 . The other end of the refill air line has a quick disconnect pressure connector  43  (the type that is closed when unconnected to another pressure connector but that opens when connected to a mating pressure connector). The first air line  34  is connected to the other leg of the T-fitting. The carrying strap assembly  38  holds the tank  36  for carrying on the body of the worker  30 . The strap assembly includes a shoulder strap  39  worn over the shoulder of the worker. A tank carrying pouch  42  is connected to the shoulder strap  39  and is positioned to locate the tank on the back of the worker in an inverted position.  
         [0023]    [0023]FIG. 7 shows the applicator tool  19  docked at the supply canister or reservoir  11  at workstation  10  for refilling of both the applicator tool  19  and the portable compressed air tank  36 . The worker  30  desirous of filling the applicator tool  19  with compound and the portable air tank  36  with compressed air, proceeds as follows. The fill nozzle  23  on the applicator tool  19  is connected to the fill attachment nozzle  17  on the transport tube  15  (for example, according to the description in Denkins I and II). Pump  16  is actuated. The fill valve  23  opens against the pressure of oncoming compound delivered by diaphragm pump  16  from the reservoir  11 . Incoming compound moves the piston rearward in the tube or toward the air inlet end. At the same time, the pressure connector  43  of refill air line  40  connects to the adaptor  29  attached to reservoir  11 . The adaptor  29  can be attached to the side of the reservoir  11  proximate the compound fill attachment nozzle  17 . The worker turns the adapter control valve  57  to fill the tank  36 . The portable compressed air tank  36  and the tube  20  refill in roughly the same amount of time, whereupon the worker  30  closes the valves  57  and  41 , respectively, and returns to work.  
         [0024]    [0024]FIG. 8 shows the adaptor  29  in greater detail. The adaptor  29  includes a first air line pressure connector  44  for connection to the refill air line  40  to fill the portable compressed air tank  36 . Suitably, the fitting  44  may include a male compressed air connector  54  for operative connection to a female connector  43  on second air line  40 . The control valve  57  operates to open and close passage of compressed air through the adaptor  29 . A refill air line connector fitting  46  connects to a supply air line  48  that extends to the manifold  18  and connects to one of the air ports thereon. Suitably, the fitting  46  also includes a male compressed air connector  58  for operative connection to a female compressed air connector  60  on the supply air line  48 .  
         [0025]    After using the adaptor  29  in filling tank  36 , control valve  57  is closed and the refill air line  40  is disconnected from the adaptor  29 . The worker  30  has accomplished the refill without removing the tank from his back or disconnecting the applicator tool and now can move freely about the work area independent of the location of the reservoir  11  and the air compressor  32 .  
         [0026]    [0026]FIGS. 9 through 11 show a second embodiment of a strap assembly indicated generally at  66  for use by a worker  68  to carry a portable air tank  36  to power the applicator tool  19 . Strap assembly  66  is fitted about the waist of the worker and carries the tank  36  from the waist of the worker on the rear side of the worker. Strap assembly  66  is ergonomically advantageous permitting the worker to carry tank  36  with enhanced comfort and reduced fatigue. As shown in FIG. 10, strap assembly  66  includes a two-part work belt  70 . A first part of the work belt  70  is a waist band  72  of sufficient length to wrap around the waist of the worker. The second part includes a belt  74 . The belt  74  is trained through belt loops  78  on the waist band  72 . The waist band  72  has at one end an outwardly facing pad  80  of hook and loop fastening material. The opposite end has an inwardly facing pad  82  of mating hook and loop fastening material. The waist band  72  is secured about the waist of the worker in conventional manner by circumventing the waist and attaching the attachment pads  80 ,  82 . The waist band  72  is made of any conventional study material such as canvas or vinyl. One end of the belt  74  has a conventional buckle  84 . The opposite end has holes or openings  86  for fastening the buckle  84 . Once the waist band  72  is in place about the waist of the worker, the belt  74  is fastened around the outside of the waist band  72  for the comfort and safety of the worker.  
         [0027]    Referring to FIGS. 10 and 11, a tank pouch  88  is connected to the two-part work belt  70 . Tank pouch  88  has a sleeve or base  89  that is cylindrical and downwardly tapered so as to conform to the curvature of the end of a compressed air tank. The tank pouch  88  is conveniently fabricated from a sturdy material such as vinyl. A loop  90  is fastened to the tank pouch  88  so that a segment of the belt  74  can be trained through it to secure the tank pouch  88  to the work belt  70 .  
         [0028]    The compressed air tank  36  fits in the tank pouch  88  in inverted fashion as shown in FIG. 9 and in phantom in FIGS. 10 and 11. A central section  92  of the sleeve  89  of tank pouch  88  can be formed of elastic in order to hug the compressed air tank  36  and inhibit movement of it. In addition, support straps  94 ,  96  can be attached to the tank pouch  88  at fixed ends and have free ends that wrap around the tank pouch with the tank installed therein. Hook and loop-type fastening pads secure the fastening straps  94 ,  96  in place. As shown in FIG. 11, an inwardly facing fastening pad  98  on a strap  94  can connect to an outwardly facing fastening pad  99  located on the sleeve  89 . The fastening pad  99  is located in a position that will cause the support strap  94  to be in tension when wrapped around the sleeve  89  with a tank  36  situated therein. Thereafter as shown in FIG. 9, the strap assembly  66  permits worker  68  to move about from place to place using the applicator tool  19  and comfortably carrying the compressed air tank  36 .