Abstract:
A method of adjusting a mix ratio of a multi-component fluid dispensed from a multi-component fluid dispensing gun includes covering a dispensing end of the multi-component fluid dispensing gun with a multi-component fluid mix ratio check nozzle for receiving at least one fluid component dispensed by the multi-component fluid dispensing gun, wherein said nozzle prevents the at least one fluid component dispensed from the multi-component fluid dispensing gun from mixing with other fluid components; directing the at least one fluid component received by the mix ratio check nozzle into a container without mixing with the other fluid components; determining at least one physical property of the at least one fluid component in the container to determine the mix ratio of the multi-component fluid dispensed from the multi-component fluid dispensing gun; and adjusting the flow of the at least one fluid component into the multi-component fluid dispensing gun to change the mix ratio of the multi-component fluid dispensed from the multi-component fluid dispensing gun.

Description:
CROSS REFERENCES TO RELATED APPLICATIONS  
       [0001]     This application is a divisional of U.S. patent application Ser. No. 10/694,238 filed on Oct. 27, 2003. 
     
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH  
       [0002]     Not Applicable.  
       TECHNICAL FIELD  
       [0003]     This invention relates to multi-component fluid dispensing devices, and in particular to a multi-component mix ratio check nozzle and method of use with a multi-component fluid dispensing gun.  
       DESCRIPTION OF THE BACKGROUND ART  
       [0004]     Manually operable guns are known for dispensing a multi-component fluid, such as a settable urethane foam, adhesive, and the like. Separate fluid components are fed individually to the gun, passed separately through control valves, and brought into contact with each other upon reaching a mixing chamber of a nozzle from which the mixed components are discharged as foam. Examples of such guns are found in U.S. Pat. Nos. 4,311,254 and 4,399,930 issued to Gary Harding, U.S. Pat. No. 4,762,253 issued to Steven H. Palmert, and U.S. Pat. No. 5,462,204 issued to Clifford J. Finn.  
         [0005]     In a multi-component, such as a settable urethane foam, the two fluid components are commonly referred to as the “A resin” and the “B resin”. They usually consist of polymeric isocyanate and polyol amine, respectively. The components are supplied separately in two pressurized containers that are attached by hoses to inlets to the guns. When the two fluid components, or resins, are mixed, the mixture quickly sets up to form a rigid foam product which is substantially insoluble and extremely difficult to remove from surfaces with which it comes in contact.  
         [0006]     The components are typically dispensed through a mixing nozzle. The gun dispenses the fluid components in a predetermined mix ratio, and the mixing nozzle mixes the components to form the multi-component fluid. The mix ratio is the ratio by volume, weight, or some other physical property, that the components of the multi-component fluid are mixed. There are a variety of mixing nozzles available which are designed to completely mix the components and produce the desired multi-component fluid. The proper mix ratio of components, however, can change over time due to the pressure of the individual components or the dispensing temperature of the components, Unfortunately, the dispensing guns do not provide any means for checking to insure the components are being dispensed at the proper mix ratio. Moreover, even if a user could determine the mix ratio of the components being dispensed, if the mix ratio is incorrect, the prior art guns do not have any means for adjusting the mix ratio.  
       SUMMARY OF THE INVENTION  
       [0007]     The present invention provides a method of adjusting a mix ratio of a multi-component fluid dispensed from a multi-component fluid dispensing gun. The method includes covering a dispensing end of the multi-component fluid dispensing gun with a multi-component fluid mix ratio check nozzle for receiving at least one fluid component dispensed by the multi-component fluid dispensing gun, wherein said nozzle prevents the at least one fluid component dispensed from the multi-component fluid dispensing gun from mixing with other fluid components; directing the at least one fluid component received by the mix ratio check nozzle into a container without mixing with the other fluid components; determining at least one physical property of the at least one fluid component in the container to determine the mix ratio of the multi-component fluid dispensed from the multi-component fluid dispensing gun; and adjusting the flow of the at least one fluid component into the multi-component fluid dispensing gun to change the mix ratio of the multi-component fluid dispensed from the multi-component fluid dispensing gun.  
         [0008]     A general objective of the present invention is to a user with the ability to check the mix ratio of fluid components produced by a multi-component fluid dispensing gun. The objective is accomplished by using a multi-component fluid mix ratio check nozzle that covers a dispensing end of a multi-component fluid dispensing gun to prevent the fluid components from mixing in order to determine the mix ratio produced by the multi-component fluid dispensing gun.  
         [0009]     Another objective of the present invention is to provide a user with the ability to adjust the mix ratio of fluid components produced by a multi-component fluid dispensing gun. This objective is accomplished by adjusting the flow of at least one fluid component flowing through the multi-component fluid dispensing gun.  
         [0010]     The foregoing and other objectives and advantages of the invention will appear from the following description. In the description, reference is made to the accompanying drawings which form a part hereof, and in which there is shown by way of illustration a preferred embodiment of the invention. Such embodiment does not necessarily represent the full scope of the invention, however, and reference is made therefore to the claims herein for interpreting the scope of the invention. 
     
    
     BRIEF SUMMARY OF THE DRAWINGS  
       [0011]      FIG. 1  is a perspective cut away view of a two component fluid dispensing system including a kit incorporating the present invention;  
         [0012]      FIG. 2  is a view in elevation of the two component fluid dispensing gun of  FIG. 1 ;  
         [0013]      FIG. 3  is a view in horizontal section taken in the plane of the line  3 - 3  of  FIG. 2 ;  
         [0014]      FIG. 4  is a detailed partial view in vertical section taken in the plane of the line  4 - 4  in  FIG. 3  showing the valve members in an open position;  
         [0015]      FIG. 5  is a detailed view of the mix ratio check nozzle detachably fixed to the two component fluid dispensing gun of  FIG. 1 ;  
         [0016]      FIG. 6  is an end view along line  6 - 6  of  FIG. 5 ;  
         [0017]      FIG. 7 . is a cross sectional view along line  7 - 7  of  FIG. 6 ; and  
         [0018]      FIG. 8  is an alternative embodiment of a multi-component fluid dispensing system incorporating the present invention. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0019]     Referring to  FIGS. 1-4 , in general, a multi-component fluid dispensing gun  5  includes a body  10  with a handle  11  that may be formed integral with the body  10 . The body  10  and handle  11  may be molded from a synthetic resin material. The body  10  is formed with a pair of longitudinal, parallel passageways  12  and  13 . The passageways  12  and  13  are divided into forward and rearward portions by an intermediate chamber  14 . The rearward portions of the passageways  12  and  13  mount brass connectors  15  that have a ribbed end for attachment to hoses  16 ,  17  connected to pressurized containers  18 ,  19  for fluid components that are used to form a multi-component fluid, such as a foam, adhesive, and the like. Each hose  16 ,  17  supplies one of the fluid components which flows through one of the passageways  12 ,  13 .  
         [0020]     The connectors  15  are hollow and define passageway inlets leading from the containers  18 ,  19  of components. The bushings  22  are also hollow and mount duck-bill valves  25  in their center. The duck-bill valves  25  are formed of a rubber or other elastomeric material and function as one-way valves to permit fluid under pressure to enter a passageway  12  or  13 .  
         [0021]     Each bushing  22  is disposed against a bellville spring  26  which bears against an end of the respective connector  15  thereby urging the bushing  22  inwardly in the passageway  12  or  13  until it abuts against a shoulder  27 . A coiled spring  30  is disposed in each of the passageways  12  and  13 . The spring  30  bears at one end against an end of a respective bushing  22 . The other ends of the springs  30  bear against the ends of brass needle valve members  31  also disposed in the passageways  12  and  13 .  
         [0022]     The needle valve members  31  span the chamber  14  and are received in both the forward and rearward portions of the passageways  12  and  13 . The needle valve members  31  have a rear portion provided with a radial recess  32  that mounts an O-ring  33  to seal with the rearward portion of the passageway  12  or  13 . The forward portion of each valve member  31  is formed as a conical needle valve portion  35  terminating in a circular cylindrical tip  36 . The conical needle valve portion  35  and tip  36  mate with a conical valve seat  37  having a circular cylindrical extension  38  and formed in the body  10  at the front terminus of the passageways  12  and  13 .  
         [0023]     The valve seats  37  define passageway outlets, and open directly through the front face of a nose  40  on the body  10 . The valve members  31  have an annular recess  39  behind the conical needle valve portion  35 . The recess  39  mounts an O-ring  41  that seals the junction of the needle valve portion  35  and the conical valve seat  37  when the valve is closed, as shown in  FIG. 4 . The valve members  31  have an additional annular recess  45  that mounts an O-ring  46  that seals with the forward portions of the passageways  12  and  13 .  
         [0024]     The chamber  14  mounts a yoke  50  formed at the top of a trigger lever  51 . The yoke  50  has a pair of arms  52  terminating in lateral bosses  53  that are received for pivotal movement in holes  54  in the two sides of the body  10 , as shown in  FIG. 4 . The yoke  50  also includes a central rib  55  which, with the arms  52 , defines two spaced cradles  56  that receive necked down portions  57  intermediate the ends of the valve members  31 . The springs  30  normally urge the valve members  31  forwardly to close the needle valves  35  against the valve seats  37 . The trigger lever  51  can be rotated to withdraw the valve members  31  against the urgings of the springs  30  to open the valves formed by the needle valve members  31  and valve seats  37 .  
         [0025]     Each valve member  31  has a central internal passage  60  that terminates in a transverse port  61  that extends to the surface of the valve member at a point between the O-rings  40  and  46 . As shown in  FIG. 4 , when the trigger lever  51  is squeezed to open the valves, fluid from the pressurized containers can pass through the central passages  60  in the valve members  31 , out the ports  61 , through the valve seats  37 , and out of the front nose  40  of the body  10 . The O-rings  46  prevent fluid from moving rearwardly along the passageways  12  or  13 . As the valves are closed, the conical needle valve portions  35  will extrude materials forwardly out of the valve seats  37 . The seating of the needle valve portion  35  in the valve seat  37  combined with the O-rings  40  will seal off the interior of the passageways  12 ,  13  and prevent air from reaching the fluid resins in such passageways  12 ,  13 .  
         [0026]     The multi-component fluid dispensing gun  5  disclosed above is substantially identical to the foam dispensing gun disclosed in U.S. Pat. No. 5,462,204 with the exception that it includes, as described below, a detachable mix ratio check nozzle for checking the mix ratio of the fluid components of the multi-component fluid dispensed by the nozzle and a means for adjusting the mix ratio. U.S. Pat. No. 5,462,204 is fully incorporated herein by reference. Although the multi-component fluid dispensing gun disclosed herein is preferred, any multi-component fluid dispensing gun that can accommodate a detachable nozzle can be used without departing from the scope of the invention.  
         [0027]     As shown in  FIGS. 2-7 , the disposable mix ratio check nozzle  65  is mounted on the front of the gun  5  which prevent the fluid components from mixing in order to check the mix ratio of the fluid components dispensed by the gun  5 . The nozzle  65  includes a pair of tubular extensions  90  extending from a base  92 . Each extension  90  is in fluid communication with one of the passageways  12 ,  13  formed through the gun  5 , and has an inlet and an outlet. Preferably, the nozzle  65  is molded from a reinforced plastic, such as a glass filled nylon.  
         [0028]     The base  92  of the nozzle  65  upstream of the extensions  90  includes an enlarged circular cylindrical portion  69  which surrounds the nose  40  of the body  10  and is sealed thereto by an O-ring  70 . The cylindrical portion  69  defines an inlet chamber  66  upstream of the extensions  90 . A wall  76  extends from between the extensions  90  through the inlet chamber  66 , and abuts the gun body  10  between the valve seats  37  to prevent the fluid components exiting the passageways  12 ,  13  from mixing as they pass through the inlet chamber  66  into the respective extensions  90 . Advantageously, the base  92  fixes the extensions  90  relative to each other for receiving the fluid components dispensed by the gun  5 .  
         [0029]     Each extension  90  is, preferably, a hollow tube formed as an integral part of the base  92 , and is in fluid communication with one of the gun passageways  12 ,  13 . Advantageously, the extensions  90  guide the fluid components away from the gun  5 , and maintain separation of the components in order to fill individual containers (not shown) with the individual components dispensed through the extension outlets. The physical properties, such as weight, volume, and the like, of the fluid components in the individual containers can then be measured to determine the mix ratio of the multi-component fluid dispensed by the gun  5 . Although each extension  90  is shown as a rigid tube having smooth exterior sides, the extensions  90  can include external ribs for attaching flexible hoses  96  to simplify filling the individual containers. Although a pair of extensions  90  is disclosed for receiving two fluid components of the two-component fluid, the nozzle can have any number of extensions equal to the number of fluid components of a multi-component fluid without departing from the scope of the invention.  
         [0030]     A pair of resilient arms  71  extend along either side of the nozzle rearwardly from the enlarged cylindrical portion  69 . The resilient arms  71  are adapted to engage ears  72  that extend from opposite sides of the body  10  adjacent the nose  40 . The resilient arms  71  have a curved portion  73  adjacent their ends which terminates in a notch  74  that mates with an ear  72 . The nozzle can be quickly attached to the body  10  by sliding the resilient arms  71  beneath the ears  72 . The curved portions  73  will cam the arms  71  so that the arms will slide easily past the ears  72  until the notches  74  engages with the ears  72 . The nozzles  65  can be easily removed by manually depressing the curved ends  73  of the arms  71  to release the notches  74  from the ears  72  and allow the arms  71  to slide past the ears  72 . Although detachably fixing the nozzle  65  to the body  10  is preferred, as described above, the nozzle  65  can be detachably fixed to the body  10  using other methods, such as by using a threaded engagement, snap fit, friction fit, fasteners, and the like, without departing from the scope of the invention. Moreover, the nozzle  65  can be held against the gun body  10  by the user without fixing the nozzle  65  to the body  10  at all without departing from the scope of the invention.  
         [0031]     Referring back to  FIGS. 1-4 , the mix ratio of the fluid components can be controlled by a clamp  94 , such as a tubing pinch valve device disclosed in U.S. Pat. No. 5,197,708 which is fully incorporated herein by reference, fixed to one of the hoses  17 . The clamp  94  is tightened to restrict the flow of the component through the hose  17  which alters the mix ratio by reducing the volume of the component that flows through the clamped hose  17  without altering the volume flowing through the unclamped hose  16 . As a result, the mix ratio of the two components change because the volume of the component flowing through the unclamped hose  16  remains unchanged while the volume of the component flowing the clamped hose  17  is reduced. Of course, if required to accomplish the desired mix ratio, the clamp  94  can be loosened to unrestrict the flow through the clamped hose  17  in order change the mix ratio of the fluid components flowing through the gun passageways  12 ,  13 . Providing a fluid flow adjusting means, such as the clamp  94  on the single hose  17  is preferred because of its simplicity and ease of retrofitting existing multi-component fluid dispensing guns. However, a clamp can be provided on each hose supplying a fluid component to the gun and other fluid flow adjusting means can be provided, such as valves disposed in the flow path of one or more of the passageways, as described below, to independently control the flow of fluid through each passageway without departing from the scope of the invention.  
         [0032]     In use, the mix ratio of the components comprising the multi-component fluid is checked by engaging the mix ratio check nozzle  65 , such that the extensions  90  are in fluid communication with the nozzle passageways  12 , 13 . The gun trigger lever  51  is then actuated to allow fluid components through the passageways  12 ,  13 . The fluid components are directed by the mix ratio check nozzle  65  into separate containers, such as bottles, plastic bags, and the like. Physical properties, such as volume, weight, and the like, of the individual fluid components are then measured to determine the mix ratio of the components when they are dispensed through the gun  5  and mixed, such as by a mixing nozzle. If the mix ratio is unacceptable, the clamp  94 , or other fluid flow adjusting means, is adjusted to increase or decrease the flow of component fluid through the hose  17  to change the mix ratio as required.  
         [0033]     In an alternative embodiment shown in  FIG. 8 , a multi-component fluid dispensing gun  100  is shown in which reference numbers used above to describe components of gun  5  are used to designate like component of gun  100 . In the gun  100  disclosed in  FIG. 8 , a mix ratio check nozzle  65  is detachably fixed to the gun  100 . Fluid flow adjusting means in the embodiment disclosed in  FIG. 8  includes a needle valve  110  disposed in each passageway (only passageway  13  is shown). The needle valve  110  controls the flow of fluid component flowing through the passageway  13  independent of the flow of the other fluid component flowing through the other passageway  12  in order to adjust the mix ratio of the fluid components dispensed by the gun  100 .  
         [0034]     The needle valve  110  includes a valve member  112  that threadably engages the gun body  10  to axially move the valve member  112  relative to a valve seat  114  and adjust the flow of fluid component flowing through the passageway  13 . Although, a needle valve  110  is disclosed, any type of valve, such as a ball cock, screw valve, and the like, disposed in the flow path of one of the fluid components can be used without departing from the scope of the invention.  
         [0035]     The mix ratio check nozzle  65  disclosed herein provides a user with the ability to easily check the mix ratio of the fluid components dispensed by the gun  5  in the field to determine whether the gun  5  is operating properly, or whether the conditions under which the gun  5  is operating produces the correct mix ratio. Moreover, the fluid flow adjusting means disclosed herein provides the user with the ability to adjust the mix ratio of the fluid components if the mix ratio is determined to be unacceptable.  
         [0036]     While there has been shown and described what is at present considered the preferred embodiment of the invention, it will be obvious to those skilled in the art that various changes and modifications can be made therein without departing from the scope of the invention defined by the appended claims.