Abstract:
An apparatus and method for analyzing a fluid wherein the apparatus comprises a transparent elongate body having a piston within a central cavity therein. The piston includes a first sealable chamber and defines a second chamber between the second end of the elongate body and the piston. The apparatus includes an opening through the second end of the elongate body and an actuator operably connected to the piston so as to draw the piston away from the opening so as to draw a second fluid into the second chamber. The method comprises introducing a volume of a control fluid into the first chamber and drawing the piston in a direction away from a second end of the elongate body so as to draw a volume of a sample fluid into the second chamber so as to permit visual comparison of the control and the sample fluids.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This application is a continuation-in-part of application Ser. No. 12/923,774 filed Oct. 7, 2010, entitled Fluid Analysis Tool, the entirety of which is hereby incorporated by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of Invention 
         [0003]    The present invention relates to fluid analysis in general and in particular to a method and apparatus for visually comparing two fluid samples. 
         [0004]    2. Description of Related Art 
         [0005]    In many applications, is desirable to analyze a fluid utilized during that process or by a particular machine. For example, in the field of automotive maintenance, it is necessary to check the condition of one or more of the fluids of the vehicle, including the oil, coolant, transmission fluid, brake fluid, differential or transfer fluid and power steering fluid. Proper monitoring and replacement of these fluids is an essential part of ensuring that the vehicle will last for the desired length of service of the vehicle. 
         [0006]    Common conventional methods of testing fluid have been to utilize an electronic testing apparatus, with chemical reaction liquids or test strips, or a density measure among others. Such methods however are expensive and time consuming to perform. Typically consumers may not want to pay for the time and expense of having such a test performed. Additionally, many consumers may be less inclined to believe a test result that is given to them by a technician as they do not have the opportunity to perform the test themselves and see the test results. For such situations, it is often advantageous to be able to show the consumer the current appearance of the fluid. 
         [0007]    Current methods of displaying fluids have been to pour the fluid in question into a container for viewing from the top and comparison with a reference chart. Such methods may not be satisfactory for all fluids, such as where one of the characteristics of the fluid to be assessed the opacity or degree of clarity. Additionally, the appearance, in particular color, may be affected by the color of the container into which the fluid is poured. The appearance of such characteristics may be adversely affected by the size, color, material or shape of the container into which the fluid is poured thereby adversely impairing the ability to compare the fluid to a reference picture which does not include these additional modifications due to the container. 
         [0008]    Additionally, it may also be advantageous to compare the fluid being tested against a clean, or baseline fluid so as to show the change in appearance of the fluid from when it was new. Current methods of doing this have been to provide two containers which may hold the base and the sampled fluid wherein the two containers may then be visually compared to each other. Such methods may be messy due to pouring multiple fluids into containers. Such methods may also occupy an unnecessary amount of time. 
       SUMMARY OF THE INVENTION 
       [0009]    According to a first embodiment of the present invention there is disclosed an apparatus for analyzing a fluid comprising an elongate body extending between first and second ends, the elongate body having a central cavity therein and a piston sealably and slidably axially moveable within the central cavity, the piston having a first sealable chamber therein and defining a second chamber within the elongate body between the second end of the elongate body and the piston. The apparatus further comprises an opening through the second end of the elongate body in fluidic communication with the second chamber and an actuator operably connected to the piston so as to draw the piston away from the opening so as to draw a second fluid into the second chamber. At least a portion of the elongate body and the piston are transparent so as to permit a visual comparison of the second fluid and a first fluid contained within the first chamber. 
         [0010]    The elongate body may include first and second end caps located at the first and second ends. The cylindrical member may extend along a central axis. The cylindrical body may be transparent. The cylindrical body may be formed of polyethylene terephthalate. 
         [0011]    The first and second end caps may be formed of a metal. The first and second end caps may be threadably secured to the cylindrical member. The second end cap may include the opening therethrough. 
         [0012]    The apparatus may further comprise a tube extending from the opening in fluidic communication therewith. The tube may be selectably connectable to the opening. The tube may be connectable to the opening by a tube connector. 
         [0013]    The actuator may comprise a rod extending from the piston. The rod may extend axially along the central axis of the elongate body. The rod may extend through an end cap of the elongate body. The rod may include a handle at a distal end thereof. 
         [0014]    The rod may be threadably received within an open end of a central cavity within the piston. The central cavity may define the first chamber. The rod may seal the open end of a blind bore within the piston. The rod may include a piston plug on the end thereof for engaging with and sealing the open end of the blind bore. The piston plug may be threadably received within the open end of the blind bore. The blind bore and piston plug may define the first chamber. 
         [0015]    According to a further embodiment of the present invention there is disclosed a method for analyzing a fluid comprising introducing a volume of a control fluid into a first chamber within a piston slidably and sealably locating the piston axially within a chamber in an elongate body. The method further comprises drawing the piston in a direction away from a second end of the elongate body so as to draw a volume of a sample fluid into a second chamber of the elongate body between the piston and the second end through an opening therein and visually comparing the control and the sample fluids to each other. 
         [0016]    Other aspects and features of the present invention will become apparent to those ordinarily skilled in the art upon review of the following description of specific embodiments of the invention in conjunction with the accompanying figures. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]    In drawings which illustrate embodiments of the invention wherein similar characters of reference denote corresponding parts in each view, 
           [0018]      FIG. 1  is a perspective view of a fluid comparison apparatus according to a first embodiment of the present invention. 
           [0019]      FIG. 2  is an exploded view of the fluid comparison apparatus of  FIG. 1 . 
           [0020]      FIG. 3  is an exploded view of the piston of the fluid comparison apparatus of  FIG. 1 . 
           [0021]      FIG. 4  is a cross-sectional view of the fluid comparison apparatus of  FIG. 1  as taken along the line  3 - 3  with the piston at a first position. 
           [0022]      FIG. 5  is a cross-sectional view of the fluid comparison apparatus of  FIG. 1  as taken along the line  3 - 3  with the piston at a second position. 
           [0023]      FIG. 6A  is a detailed view of a quick release coupler of the apparatus of  FIG. 1  at a locked position according to a further embodiment of the present invention. 
           [0024]      FIG. 6B  is a detailed view of a quick release coupler of the apparatus of  FIG. 1  at a release position according to a further embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0025]    Referring to  FIGS. 1 through 5 , an apparatus for analysing a fluid according to a first embodiment of the invention is shown generally at  10 . The apparatus  10  comprises an elongate cylindrical body  12  comprising a tube  13 , extending between first and second ends  14  and  16 , respectively and having a cavity  18  therein and a piston  60  slidably and sealably received within the cavity. The piston  60  includes a first chamber  20  therein and defines a second chamber  22  within the cavity  18 . The apparatus  10  further includes first and second end caps,  40  and  50 , respectively, enclosing the first and second chambers  20  and  22  and a pick-up tube  90  extending from the second end cap  50   
         [0026]    Each of the first and second ends  14  and  16  may include exterior threading,  24  and  26 , respectively, for securing the first and second end caps  40  and  50  thereto as will be further explained below. The tube  13  includes a central bore  28  extending therethrough along a central axis sized to receive the piston  60  therein. As illustrated and described above, the tube  13  may be cylindrical, although it will be appreciated that other cross-sectional shapes may be useful as well, such as, by way of non-limiting example, triangular, square, octagonal, oval, or irregular provided the piston  60  is sized and shaped to be sealably received therein so as to prevent mixing of the fluids contained in each of the first and second chambers. The tube  13  may be formed of any suitable material selected to be substantially transparent. Optionally the tube  13  may be formed to have a transparent portion so as to permit observation of the contents of the apparatus. In particular, the tube may be formed of any suitable transparent material which is impact resistant and chemically neutral with common automotive fluids, such as by way of non-limiting example co-polymerized polyethylene terephthalate (PETG). 
         [0027]    The first end cap  40  includes a disk portion  41  and a sleeve portion  43  at a distal edge thereof. The first end cap  40  encloses the first end  14  of the tube  13  within an interior thereof. Optionally, the first end cap  40  may include interior threading  42  adapted to engage with the exterior threading  24  on the first end  14  of the tube  13  although other means for securing the end caps to the tube may be utilized as well. In this way, the first end cap  40  may be threadably secured onto the first end  14  of the tube  13 . The first end cap  40  also includes an extension  44  extending axially from the disk portion  41 . The extension  44  includes a bore  46  therethrough sized to pass a rod as will be further described below. 
         [0028]    The second end cap  50  includes a disk portion  51  and a sleeve portion  53  at a distal edge thereof. The second end cap  50  encloses the second end  16  of the tube  13  within an interior thereof. Optionally, the second end cap  50  may include interior threading  52  adapted to engage with the exterior threading  26  on the second end  16  of the tube  13  although other means for securing the end caps to the tube may be utilized as well. In this way, the second end cap  50  may be threadably secured onto the second end  16  of the tube  13 . The first end cap  50  also includes an extension  54  extending axially from the disk portion  51 . The extension  54  includes a threaded bore  56  therethrough to receive a drawing tube connection as will be more fully described below. The threaded bore  56  also maintains the second chamber  22  which is adjacent to the second end cap  50  in fluidic communication with the drawing tube connection. The first and second end caps may be formed of any suitable material such as steel, brass, copper, stainless steel, plastics, ceramics or any other suitable material. 
         [0029]    The piston  60  comprises an elongate tubular member extending between first and second ends,  62  and  64 , respectively and has an exterior surface  66 . The exterior surface  66  is sized and shaped to closely correspond to the central bore  28  of the tube  13 . The exterior surface  66  also includes a groove  67  therearound adapted to receive an o-ring  69  or other suitable seal therein. 
         [0030]    The o-ring  69  seals the space between the piston  60  and the tube  13  so as to sealably isolate the second chamber  22 . 
         [0031]    As illustrated in  FIG. 3 , the piston includes a piston bore  68  formed therein extending from the second end  64  of the piston. The piston bore includes an open end or section  120  and an unobstructed portion  122 . The piston bore  68  threadably and sealably receives an actuator rod  70  therein so as to enclose and seal the first chamber  20 . The actuator rod  70  may optionally include a piston plug  65  on a distal end thereof which is received within open end  120  of the piston bore  68 . With reference to  FIG. 3 , the open end  120  of the piston includes internal threading  124  therein and a chamfered entrance  126 . The piston plug  65  includes a threaded portion  130  corresponding to the internal threading  124  of the piston. The piston plug includes a top flange  132  adapted to bear against the first end  62  of the piston  60 . A seal  140 , such as, by way of non-limiting example, an 0-ring is provided to be located between the first end  62  of the piston  60  and the top flange  132  of the piston plug  65 . As the piston plug  65  is tightened into the piston bore  68 , the o ring  140  is compressed between the top flange  132  and the first end  62  of the piston  60  so as to seal the first chamber  20  within the piston. It will be appreciated that the chamfered entrance  126  assists in providing such seal by compressing the o-ring  140  against both the top flange  132  and the threaded portion  130  of the piston plug  65  as well as against the chamfered entrance  126  of the piston. After locating the rod  70  or the piston plug  65  within the open end  120 , the unobstructed portion  122  will be isolated from the exterior of the piston such that any fluid introduced into the first chamber  20  will be isolated from any other fluids introduced to the apparatus as discussed further below. The piston  60  may be similarly formed of transparent materials as the tube  13 . 
         [0032]    As set out above, the first chamber  20  is formed within the piston  60  and is defined by the piston bore  68  as sealed by the piston plug  65 . The second chamber  22  is formed between second end  64  of the piston and the second end cap  50 . 
         [0033]    The apparatus  10  further includes an actuator which, as illustrated in the accompanying figures may comprise a rod  70 . The rod  70  has a diameter selected to be received within the bore  46  of the first end cap  40  and form a seal therebetween so as to seal the first chamber  20 . The rod  70  includes a first threaded end  72  and a handle  74  at a second end. The rod  70  also includes a compression rod spring  76  located therearound, the purpose of which will be described below. The handle  74  may comprise a finger grip style handle as illustrated in  FIG. 1  having finger grip locations  78 . 
         [0034]    Optionally, the handle may comprise a circular knob-type handle as illustrated in  FIG. 2-5  or any other suitable handle type as will be appreciated. 
         [0035]    The second end cap  50  includes a quick release coupler  80  connected thereto as are commonly known. The quick release coupler  80  includes a threaded end  82  and an open end  84 . The open end  84  includes a quick release ring  86  which may be pulled backwards in a direction generally indicated at  88  to release or attach a corresponding coupler connected to the pick-up tube  90  as will be explained below. The quick release coupler  80  includes a bore therethrough (not shown) so as to maintain the second chamber  22  in fluidic communication with the pick-up tube  90  when attached. The quick release coupler  80  may optionally be valved so as to close and seal the second chamber  22  from the outside environment when a pick-up tube  90  is not connected thereto as are commonly known. As illustrated in  FIGS. 6A and 6B , the quick release coupler  80  may include a slot  150  extending into the quick release ring  86  from the edge closest to the second end cap  50 . The quick release coupler  80  may further include a pin or protrusion  152  extending from therefrom which is sized to be slidably located within the slot  150 . The pin  152  is positioned to prevent movement of the quick release ring  86  during normal operation by abutting against the edge closest to the second end cap  50  as illustrated in  FIG. 6A . When a user desires to release the pick-up tube  90  from the quick coupler, the quick release ring  86  may be rotated to align the slot  150  with the pin and thereafter retracted in the direction generally indicated at  88 . Thereafter the pick-up tube  90  may be removed therefrom in the direction generally indicated at  154 . 
         [0036]    The pick-up tube  90  comprises an elongate tube having an open end  92  and a connection end  94 . The connection end  94  includes a quick connection plug  96  operable to cooperate with the quick connection socket of the quick release coupler  80  to be interconnected therewith. The pick-up tube  90  may have a length selected according to the desired application. By way of non-limiting example, the pick-up tube  90  may have a length between of 6 and 48 inches (152 and 1219 mm) although it will be appreciated that different lengths may be useful for use with different fluids and automotive types. It will be appreciated that other ranges may be useful as well depending upon the application and the distance between a fluid source and the availability of user access thereto. It will also be appreciated that the use of a quick-connect style coupler as described above will facilitate the use of pick-up tubes  90  of differing lengths. The pick-up tube  90  may be formed of any suitable material such as natural or synthetic rubber, silicone, plastics such as polyethylene or polystyrene, and may optionally be flexible so as to facilitate introduction of the pick-up tube  90  into a variety of fluid sources. 
         [0037]    The apparatus  10  is assembled by passing the tube  90  through the bore in the first end cap and threadably securing the threaded end  72  into the piston bore  68  such that the rod spring  76  is between the piston and the first end cap. The piston  60  may then be located within the central bore  28  of the tube  13 . The second end cap  50  may be threadably secured onto the second end  16  of the tube  13  and the threaded end  82  of the quick release coupler  80  threadably secured into the threaded bore  56  of the second end cap  50 . 
         [0038]    With reference to  FIGS. 3 and 4 , in operation, a sample of a reference fluid may be introduced by pouring or otherwise into the open first piston bore  68  of the piston  60  in a direction generally indicated at  100 . The piston plug  65  may then be secured within the piston bore  68  with the o-ring  140  therebetween so as to seal the reference fluid within the first chamber. Thereafter the rod  70  may be passed through the first end cap  40  and secured within internal threading  128  of the piston plug. After sealing the reference fluid within the piston, the piston  60  may then be located within the cavity  18  of the elongate cylindrical body  12  to a position adjacent to the second end cap  50  by pushing the handle  74  towards the second end cap  50  in a direction generally indicated at  102  and the first end cap  40  threaded onto the first end  14  of the cylindrical body. 
         [0039]    To test a sample, the quick connection plug  96  may be secured within the quick release coupler  80  so as to attach a pick-up tube  90  to the cylindrical body  12  and second end cap  50 . The open end  92  of the pick-up tube  90  may then be inserted into a fluid reservoir (not shown) of the fluid to be tested and the handle  74  drawn away from the second end cap  50  in a direction generally indicated at  104  so as to draw the sample fluid into the second chamber  22  through the pick-up tube  90 . Thereafter the apparatus may be held up for visual inspection by a user so as to compare the appearance of the reference fluid in the first chamber  20  and the sample fluid in the second chamber  22 . By way of non-limiting example the color of each fluid may be compared to each other, the clarity of each fluid may be compared to each other or the thickness or viscosity of each fluid may be compared to each other by moving the apparatus to observe the relative movement of each fluid therein. During and after the process of drawing the sample fluid into the second chamber  22 , the rod spring  76  serves as a cushion between the piston  60  and the first end cap  40 . 
         [0040]    While specific embodiments of the invention have been described and illustrated, such embodiments should be considered illustrative of the invention only and not as limiting the invention as construed in accordance with the accompanying claims.