Abstract:
Disclosed is an apparatus and method for analyzing a fluid. The apparatus comprises an elongate body having a piston therein defining first and second chambers within the elongate body, an opening through 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. At least a portion of the elongate body is transparent so as to permit a visual comparison of the second fluid and a first fluid contained within the first chamber. The method comprises introducing a volume of a control fluid into the first chamber, slidably and sealably moving the piston in a direction away from the opening so as to draw a volume of a sample fluid into the second chamber and visually comparing the control and the sample fluids to each other.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of Invention 
         [0002]    The present invention relates to fluid analysis in general and in particular to a method and apparatus for visually comparing two fluid samples. 
         [0003]    2. Description of Related Art 
         [0004]    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 and brake 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. 
         [0005]    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. 
         [0006]    Current methods of displaying fluids has 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. 
         [0007]    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 
       [0008]    According to a first embodiment of the present invention there is disclosed an apparatus for analyzing a fluid comprising an elongate body having a central cavity therein and a piston sealably and slidably axially moveable within the central cavity, the piston defining and sealably separating first and second chambers within the elongate body. The apparatus further comprising an opening through 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 is transparent so as to permit a visual comparison of the second fluid and a first fluid contained within the first chamber. 
         [0009]    The elongate body may be formed of a cylindrical member and opposed first and second end caps. The cylindrical body may extend along a tool axis. The cylindrical body may be transparent The cylindrical body may be formed of polyethylene terephthalate. 
         [0010]    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 first end cap may be selectably -removable so as open the first chamber permitting the first fluid to be introduced thereto. The second end cap may include the opening therethrough. 
         [0011]    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. 
         [0012]    The actuator may comprise a rod extending from the piston. The rod may extend axially along an axis of the tool. The rod may extend through an end cap of the elongate body. The rod may include a handle at a distal end thereof. 
         [0013]    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 of an elongate body, slidably and sealably moving a piston along the elongate body in a direction towards the first chamber so as to draw a volume of a sample fluid into a second chamber of the elongate body through an opening therein and visually comparing the control and the sample fluids to each other. 
         [0014]    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 
         [0015]    In drawings which illustrate embodiments of the invention wherein similar characters of reference denote corresponding parts in each view, 
           [0016]      FIG. 1  is a perspective view of a fluid comparison apparatus according to a first embodiment of the present invention. 
           [0017]      FIG. 2  is an exploded view of the fluid comparison apparatus of  FIG. 1 . 
           [0018]      FIG. 3  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. 
           [0019]      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 second position. 
       
    
    
     DETAILED DESCRIPTION 
       [0020]    Referring to  FIG. 1 , 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 , 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  separates the cavity  18  into and defines first and second chambers  20  and  22 , respectively, 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   
         [0021]    With reference to  FIG. 2 , the cylindrical body  12  comprises a tube  13  having first and second ends  14  and  16 . 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  30  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). 
         [0022]    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. 
         [0023]    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. 
         [0024]    The piston  60  comprises an elongate tubular member extending between first and second ends,  62  and  64 , respectively and has an exterior surface  66 . 
         [0025]    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. The o-ring  69  seals the space between the piston  60  and the tube  13  so as to sealably separate the first and second chambers  20  and  22 . As illustrated in  FIG. 1 , the first chamber  20  is formed between the first end  62  of the piston  60  and the first end cap  40 . The second chamber  22  is formed between second end  64  of the piston and the second end cap  50 . The first end  62  of the piston  60  also includes a piston bore  68  therein. The piston bore  68  threadably receives an actuator rod  70  therein. The piston bore  68  may optionally be carried within a piston plug  65  engaged within a cavity in the piston  60  as illustrated in  FIGS. 3 and 4 . The piston  60  may be similarly formed of transparent materials as the tube  13 . 
         [0026]    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 circular knob-type handle as illustrated in  FIGS. 2 through 4 . Optionally, the handle may comprise a finger grip style handle as illustrated in  FIG. 1  having finger grip locations  78  or any other suitable handle type as will be appreciated. 
         [0027]    The second end cap  50  includes a quick coupler  80  connected thereto. The quick coupler  80  includes a threaded end  82  and an open end  84 . The open end  84  includes a quick release ring  86  forming a quick-connection socket 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 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 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. 
         [0028]    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 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 30 inches (152 and 762 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. 
         [0029]    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 coupler  80  threadably secured into the threaded bore  56  of the second end cap  50 . 
         [0030]    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 end  14  of the tube  13  in a direction generally indicated at  100 . The first end cap  40  may then be threadably secured to the first end of the tube such that the reference fluid is retained within the first chamber  20  between the piston  60  and the first end cap  40 . The piston may then be located 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 . Optionally, the piston  60  may be located adjacent to the second end cap  50  before the reference fluid is introduced to the first chamber  20 . 
         [0031]    To test a sample, the quick connection plug  96  may be secured within the quick 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 . 
         [0032]    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.