Abstract:
A visible vapor generator is provided. The visible vapor generator may include: a pump having an inlet and an outlet; and a passage configured to provide a fluid to an impeller associated with the pump in addition to lubricating fluid and working fluid provided to the pump; wherein the action of the impeller atomizes both at least some of both the lubricating fluid and the fluid provided to the impeller and expels the atomized fluid through the outlet. A method of generating a vapor may also be provided. The method may include; modifying a pump to have a passage to conduct fluid to an impeller associated with the pump in addition to the lubricating fluid and working fluid.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates generally to a system for generating smoke. More particularly, the present invention relates to a method and apparatus for generating a visible vapor which may commonly be referred to as smoke. 
       BACKGROUND OF THE INVENTION 
       [0002]    When servicing components of an automobile, one common task is to find leaks in a closed system such as an engine or other components. Current leak detecting system utilizes a smoke or atomized mineral oil where the mineral oil is turned into smoke or atomized by use of a heating element. The smoke is then pumped into the closed system and any leaks will be visible to the naked eye, because the smoke will be seen coming from the leak in the system. 
         [0003]    Accordingly, it is desirable to provide a method and apparatus that can generate a visible vapor or “smoke” that can be inserted under pressure into a closed system for detecting leaks. 
       SUMMARY OF THE INVENTION 
       [0004]    The foregoing needs are met, to a great extent, by the embodiments of the invention, wherein in one aspect an apparatus is provided that in some embodiments a method or apparatus is provided for producing a visible fluid (smoke) and pressuring the smoke to pump the smoke into a system to detect leaks. 
         [0005]    In accordance with one embodiment of the present invention, a visible vapor generator is provided. The visible vapor generator may include: a pump having an inlet and an outlet; and a passage configured to provide a fluid to an impeller associated with the pump in addition to lubricating fluid and working fluid provided to the pump; wherein the action of the impeller atomizes both at least some of both the lubricating fluid and the fluid provided to the impeller and expels the atomized fluid through the outlet. 
         [0006]    In accordance with another embodiment of the present invention, a visible vapor generator is provided. The visible vapor generator may include; a means for generating pressure having an inlet and an outlet; and a means for providing fluid communication to the pressure generating means in addition to lubricating fluid provided to the pressure generating means; wherein the action of the pressure generating means atomizes at least some of both the lubricating fluid and the fluid provided to the impeller and expels the atomized fluid through the outlet. 
         [0007]    In accordance with yet another embodiment of the present invention, a method of generating a vapor is provided. The method may include; modifying a pump to have a passage to conduct fluid to an impeller associated with the pump in addition to the lubricating fluid and working fluid. 
         [0008]    There has thus been outlined, rather broadly, certain embodiments of the invention in order that the detailed description thereof herein may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional embodiments of the invention that will be described below and which will form the subject matter of the claims appended hereto. 
         [0009]    In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of embodiments in addition to those described and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein, as well as the abstract, are for the purpose of description and should not be regarded as limiting. 
         [0010]    As such, those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]      FIG. 1  is a perspective view illustrating a pump that has been modified in accordance to an embodiment of the present invention. 
           [0012]      FIG. 2  is an exploded perspective view of a portion of the pump shown in  FIG. 1  that has been modified according to an embodiment in accordance with the invention. 
           [0013]      FIG. 3  is a cross-sectional view of a rotary vane vacuum pump that has been modified in accordance with the embodiment of the invention. 
           [0014]      FIG. 4  is a cross-sectional view of a portion of a rotary vane vacuum pump taken along the line of  4 - 4  as shown in  FIG. 5 . 
           [0015]      FIG. 5  an exploded view of a portion of a rotary vane vacuum pump that has been modified in accordance with an embodiment of the invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0016]    According to some embodiments of the invention a visible vapor commonly referred herein to as “smoke” is generated for use in leak detection. While the term “smoke” is commonly used herein, it should be understood that in accordance with several embodiments of the invention, there is no combustion or addition of heat associated with the generation of the visible vapor or smoke. 
         [0017]    The term “smoke” as used herein refers to a visible vapor and is not limited to results of a combustion process. An apparatus may be made in accordance with the invention or other apparatus may be adapted such as a rotary vane pump, for example, to generate a desired amount of smoke in accordance with the invention. 
         [0018]      FIG. 1  shows a rotary vane pump that has been adapted or modified to produce a desired amount of smoke in accordance with an embodiment of the invention. The pump  10  includes an intake fitting  12 . The intake fitting  12  includes a metering valve  12 . Examples of a metering valve  12  may include, but are not limited to a needle valve, a solenoid valve or other control valve. The needle valve  14  can be controlled and/or adjusted to provide a desired intake opening. For example, in accordance with some embodiments of the invention the desired intake opening is about 0.06 of an inch in diameter. The needle valve  14  is located at the intake  16 . 
         [0019]    An oil fill port  18  is included to permit a user to add lubricating oil to the pump  10 . In accordance with some embodiments of the invention the lubricating oil is mineral oil. A sight glass  20  permits a user to see how much oil is in the reservoir filled by the oil fill port  18 . The pump  10  includes a housing  22 . A drain  24  permits the lubricating oil to be drained for purposes of maintenance or any other reason. 
         [0020]    The pump  10  includes a base  26  for supporting the pump  10 . An isolation valve  28  is shown in the smoke generating pump  10 , however, the isolation valve is not a necessary component of the invention. The isolation valve  28  can optionally allow the system being serviced by the pump  10  to be isolated from the ambient conditions. Pump  10  includes a high torque motor  30 . The high torque motor  30  is contained within the housing  22  of the pump  10 , but is located generally where the reference numeral  30  indicates. The pump  10  includes a power switch  32  which allows the pump  10  to be turned on or off by a user. 
         [0021]    The pump  10  shown in  FIG. 1  includes a through the handle exhaust system  34 . The pump  10  exhausts the working fluid (a.k.a. pumped fluid) through the handle  36 . The handle  36  includes an exhaust port  38 . In other embodiments the working fluid is not exhausted through the handle. Rather, the exhaust port  38  is located at a different location on the pump  10 . In accordance to some embodiments of the invention, the exhaust port  38  is equipped with an exhaust fitting  40 . The exhaust fitting  40  permits the connection of a hose  42  to the exhaust port  38  in order to direct the exhausted working fluid through the hose  42 . 
         [0022]    In some embodiments of the invention, the visible smoke will be generated in the working fluid that is exhausted by the pump  10 . The smoke can be directed through the hose  42 . The hose  42  includes a hose fitting  44 . The hose fitting  44  allows the hose  42  to be connected to a system that is to be tested for leaks or any other system where it is desired to insert the exhausted working fluid from the pump  10 . 
         [0023]    A pressure switch  46  where it is located near the exhaust port  38  and may be configured to monitor pressure of the working fluid which may include the smoke exiting the exhaust port  38 . In some embodiments of the invention, the pressure switch  46  monitors the gauge pressure of the fluid exhausted through the pump  10 . 
         [0024]    As shown in  FIG. 2  and explained later below, the pressure switch  46  maybe operably connected to a solenoid  47  which operates the needle valve  14 . The pressure switch  46  may operate the needle valve  14  via the solenoid  47  in accordance with the pressure detected by the pressure switch  46 . 
         [0025]      FIG. 2  illustrates a portion of pump  10  in an exploded condition. While many features of a pump  10  are well known or described above, they are described below in detail. However, some features which are new or modified to allow the pump  10  to generate smoke in accordance to the embodiment of the invention will be described in additional detail. 
         [0026]    As shown in  FIG. 2 , the pump  10  includes a pressure switch  46  operatively connected to a solenoid  47 . The solenoid  47  is operatively connected to the needle valve  14 . According to some embodiments of the invention, the orifice associated by the needle valve  14  allowing air to be sucked into the pump  10  is about 0.06 inches in diameter. 
         [0027]    In some embodiments this size can be enlarged or made smaller by the manipulation of the needle valve  14  by either the solenoid  47  or a user. The nominal size of 0.06 inches size can be modified according to the needs of an individual application. If the pressure of the working fluid exiting through the exhaust port  38  is too great, the pressure switch  46  may cause the solenoid  47  to control the needle valve  14  reduce to size of the orifice or even to completely close the needle valve  14  thereby not letting any additional air be sent into the pump via the intake  16 . 
         [0028]    An algorithm for operating the solenoid  47  in response to the measured pressure may be determined by a user or may be preprogrammed into a microcontroller by the manufacturer. In accordance to some embodiments of the invention, if the pressure of the working fluid exiting the exhaust port  38  exceeds one-half PSI or about 15 inches of water, the needle valve  14  will be moved to a completed closed position. 
         [0029]      FIG. 2  shows a drive train assembly  48  which operatively connects the motor  30  to an impeller (not shown in  FIG. 2 ). A module assembly  50  is also shown. A module assembly  50  may include an oil drain cap  52 , an oil drain kit  54 , a module cover  56 , and a module  58 . These parts will not be explained in detail as they are not particularly relevant to certain embodiments in accordance with the invention. 
         [0030]    A plate  60  is located between the module assembly  50  and the rotary pump portion  62 . The rotary pump portion  62  receives the intake fitting  12  containing the needle valve  14  at the intake  16  and portion is supported by the base  26  and receives the isolation valve  28 . The handle  36  is located near the motor  30  and includes the exhaust port  38  and the exhaust fitting  12 . The exhaust fitting  12 , as described above, accepts the hose  42  which may in some embodiments include a nozzle or fitting  44 . While the pump  10  has been shown as one example embodiment of the invention, it is certainly not intended to be limiting. Other layouts maybe used including those that do not include a through the handle exhaust system  34 . 
         [0031]      FIG. 3  is a cross-section of a rotary vane pump portion  62  that may be used in accordance with some embodiments of the invention. The rotary vane pump portion  62  may include an inlet  64 , an outlet  66 , and housing  68 . A rotor  70  includes multiple vanes  72  and  74 . The vanes  72  and  74  maybe biased to an outward position by a spring  75 . The vanes  72  and  74  may move in and out as indicated by arrows E. The vanes  72  and  74  are biased to the outward position. Outward being described as urging against the housing  68 . 
         [0032]    In accordance with some embodiments of the invention, an end plate  76  together with the housing  68  encloses the pump  62 . The end plate  76  is shown in phantom lines and is shown as a “see through” object in order to allow the parts such as the rotor  70  and vanes  72  and  74  and spring  76  along with the housing  22  to be shown. The end plate  76  may include an orifice or opening  76  which may allow a fluid other than the working fluid to be introduced to the mechanical features of the pump. The fluid that maybe introduced is atomized by the working action of the pump mixed in with the working fluid and is expelled out the outlet  66 . 
         [0033]    The rotary vane pump maybe operated in a manner as described below. A rotor  70  is rotated in the direction as shown in by arrow D. Working fluid which maybe air is input into the inlet  64  shown by arrow A by the operation of the pump. As the rotor  70  rotates the direction of arrow D, the spring  75  urges the vanes  72  and  74  in an outward position. As vanes  72  and  74  move the working fluid in the direction of arrow C the working fluid is moved creating a suction at the inlet  64 . Which causes additional working fluid such as air to enter the inlet  64 . 
         [0034]    As the rotor  70  continues to rotate, the vane  72  and  74  are continued to be urged in an outward direction and held by the housing  22 . The working fluid continues to moved in the directions of arrow C where it eventually exits through the outlet  66  in direction of B. 
         [0035]    Rotary pumps  62  may include a lubricating fluid to allow lubrication between the vanes  72  and  74  and the housing  22  and the rotor  70 . In some embodiments, the fluid maybe mineral oil. In other embodiments, other fluid may be used. The action of the rotor  70 , the vanes  72  and  74 , and the housing  22  atomizes a certain amount of the lubricating oil causing it to become a visible vapor. Therefore, when the working fluid exits out the outlet  66  it also contains visible vapor which is atomized lubricating oil. However, in accordance to some embodiments of the invention, an additional amount of visible vapor is desired in addition to what is generated by the atomization of the lubricating fluid. Therefore, additional fluid is provided via the orifice  78  in order for it to also be atomized. Therefore, when the working fluid exits the outlet  66  additional visible vapor is contained in the working fluid and maybe seen. 
         [0036]    In some embodiments of the invention, the orifice  78  may provide a fluid passage from the lubricating oil reservoir to the rotor  70  and the vanes  72  and  74 . The orifice  78  provides a way for fluid to contact the vanes  72  and  74 , the rotor  70  to and the housing  22  in addition to the regular lubricating pathway the lubricating fluid. 
         [0037]    In some embodiments of the invention, the orifice  78  maybe about 0.002 inches in diameter. Other embodiments may include a separate reservoir then the regular reservoir of lubricating fluid for of fluid providing additional fluid to be exposed to the working features of the pump to be atomized. 
         [0038]      FIG. 4  shows an end view of a rotor  70  according to another embodiment of the invention. The rotor  70  has vanes  72  and  74  which are not actually aligned as shown in  FIG. 3 . The rotor  70  is mounted to a shaft  80  and contains vanes  72  and  74 . 
         [0039]      FIG. 5  is an exploded side view of a rotary pump  62  modified to in accordance with another embodiment of the invention similar to that shown in  FIG. 4 . As shown in  FIG. 5 , an end plate  76  includes an orifice  78 . The orifice  78  may permit fluid to be exposed to the working features of the pump  62  similar to the orifice  78  described with respect to  FIG. 3 . When the pump  62  is assembled, the end plate  76  is held tightly against the pump housing  22  by a screw  82 . The pump housing  90  may include a reed valve or a limiter  86  held in place by a screw  84 . The shaft  80  may support the rotor  70  which supports the vanes  72  and  74 . The shaft  80  may also be held in place by an inlet plate  94 . The shaft  80  may extend through the inlet plate  94  and may attach to a motor for turning the shaft  80 . 
         [0040]    Additional details regarding the pump are not shown or described as they are not particularly relevant to the invention and may be already known in the art. While the examples listed here have discussed rotary vane pumps for atomizing a fluid. Other types of pumps maybe used. In accordance with some embodiments of the invention a typical pump maybe modified to include an orifice or hole for providing additional fluid to the mechanical moving parts of the pump in order to provide additional fluid to be atomized in addition to any lubricating fluid that may be atomized by the mechanical action of the pump. The atomized fluid in the form of a visible vapor or smoke may be mixed with the working fluid of the pump and exhausted out of the pump via the outlet. This pressurized visible fluid may then be used for leak detection or any other desired purpose. 
         [0041]    The many features and advantages of the invention are apparent from the detailed specification, and thus, it is intended by the appended claims to cover all such features and advantages of the invention which fall within the true spirit and scope of the invention. Further, since numerous modifications and variations will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation illustrated and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.