Abstract:
An apparatus for measuring the level of a fluid in a chamber is disclosed. The apparatus generally includes an indicator rod and a tubular member in fluid communication with the chamber. The indicator rod is a measuring rod operable to be immersed in the fluid in the chamber to indicate the level of fluid therein. The indicator rod also includes a locking mechanism to releasably engage the flange of the tube to restrain the movement of the indicator rod. The locking mechanism selectively engages a flange or the tube to lock the indicator rod to the tube. A seal between the indicator rod and the tube seals the chamber when the indicator is secured to the tube.

Description:
FIELD OF THE INVENTION  
         [0001]    The present invention relates to a device for measuring the fluid level in a chamber. More specifically, the present invention relates to a device for measuring the fluid level in a chamber having a locking mechanism and a deformable seal for sealing the measuring device to the chamber.  
         BACKGROUND OF THE INVENTION  
         [0002]    In internal combustion engines, transmissions, and other machinery requiring fluids for lubrication and cooling, it is known to use a fluid measuring device for indicating the fluid level in a participation fluid chamber. Typically, the fluid measuring device is a dipstick for checking the level of fluid. The dipstick is normally an elongated indicator that is slidably located within a conduit or tube attached to the chamber. When the dipstick is fully inserted into the tube, one end is immersed into the fluid in the chamber. When an actual reading of the fluid level is desired, the other end of the dipstick is pulled from the tube, thereby removing the entire dipstick from the conduit and chamber to allow the user to read the fluid level from the one end. The dipstick is then reinserted into the chamber once the fluid level has been checked.  
           [0003]    The dipstick is typically coupled to the tube by a simple mechanical connection such as a sleeve. The sleeve extends over the outer surface of the tube and is held in place by gravitational or frictional forces between the sleeve and the tube. This connection, while simple and cost effective, does not prevent possible contamination of fluid in the fluid holding compartment. Additionally, it may be desirable to isolate a system from pressure changes. However, presently known devices do not allow the chamber to be sealed from external pressure changes.  
         SUMMARY OF THE INVENTION  
         [0004]    In one form, the present invention provides an apparatus for measuring the level of a fluid in a chamber. The apparatus includes an indicator rod having a first end and a second end, the first end of the indicator rod adapted to be immersed in the fluid to measure the height of the fluid in the chamber. The apparatus also includes a tube in fluid communication with the chamber having a first end connected to the chamber and the second end having a flange. A handle is coupled to the first end of the indicator rod and adapted to releasably engage the flange of the tube to restrain movement of the handle. A seal located between the handle and the tube is deformable upon engagement of the handle to the tube to form a locked and sealed interface between the tube and the handle.  
           [0005]    Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limited the scope of the invention.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0006]    The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein:  
         [0007]    [0007]FIG. 1 is a front view of a fluid level indicator assembly in a locked position according to the present invention;  
         [0008]    [0008]FIG. 2 is a front view of the fluid level indicator assembly of FIG. 1 in an unlocked position;  
         [0009]    [0009]FIG. 3 is a front view of the fluid level indicator of FIG. 1; and  
         [0010]    [0010]FIG. 4 is a cross sectional view of the tube of FIG. 1. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0011]    The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses.  
         [0012]    With reference to FIG. 1, a front view of a fluid level indicator assembly  10  is shown in accordance a first embodiment of the present invention. The fluid level indicator assembly  10  is shown to include a tube  12  in fluid communication with a fluid chamber  14  and an indicator  16  adapted to engage the tube  12  and extend into the fluid chamber  14 . In operation, the fluid level indicator assembly  10  allows the user to check the level of the fluid  18  in the fluid holding compartment  14 . The fluid level indicator assembly  10  also allows the user to attach the indicator  16  to a portion of the tube  12  using a locking mechanism  38 .  
         [0013]    The fluid level indicator  16  of the present invention is shown in combination with an exemplary fluid holding compartment  14 . However, it is understood that the fluid holding compartment  14  may represent any one of a number of fluid holding compartments  14  such as a fluid lubrication system of an internal combustion engine, transmission, or other machine.  
         [0014]    As shown in FIGS.  1 - 4 , the tube  12  generally includes a tubular main body portion  20  having a first end  22  and a second end  24 . The first end  22  of the tube  12  is connected to the fluid chamber  14  to allow fluid communication therebetween. The first end  22  of the tube  12  may be attached to the fluid holding compartment  14  using any commonly known devices such as a mechanical fitting, adhesive connection, or weld, etc. The tubular main body portion  20  is shown to be generally linear in form and have a opening  26  extending therethrough. It is readily appreciated that the tubular main body portion  20  may be formed in a variety of shapes including bends and angles to allow the tube  12  to be routed around objects and not depart from the scope of the present invention. The second end  24  of the tube  12  is formed to have a flange  28 . The flange  28  allows the indicator  16  to engage the tube  12 . As shown, the flange  28  extends annularly around the second end  24  of the tube  12  and includes an engagement surface  30  along the underside of the flange  28 . Also, a funnel  32  is formed between the flange  28  and the opening  26  of the tube  12  to allow the indicator  16  to be guided into the opening  26  of the tube  12 . However, it is appreciated that the flange  28  may be formed in a variety of configurations and not depart from the scope of the present invention.  
         [0015]    The indicator  16  generally includes a measuring rod  34  adapted to be disposed in the tube  12 , a main body portion  36  coupled to the measuring rod  34  and adapted to be partially inserted into the opening  26  of the tube  12 , the locking mechanism  38  adapted to engage a portion of the flange  28 , and a handle  40  allowing the user to manipulate the indicator  16 .  
         [0016]    The measuring rod  34  is an elongated member  42  having a first end  44  adapted to be immersed in the fluid  18  contained in the fluid holding compartment  14  and a second end  46  adapted to be connected to the main body portion  36 . In one form, the measuring rod  34  is flexible, and may be formed of thin metal. The measuring rod  34  includes indicator marks  48  at the first end  44  to indicate the level of the fluid  18  in the fluid chamber  14 .  
         [0017]    The main body portion  36  generally includes a disk-shaped member  50  having a stopper  52  disposed at a first side thereof. The disk-shaped member  50  is formed to be at least as large as the flange  28  of the tube  12  to allow the disk-shaped member  50  to cover the flange  28 . The barrel-shaped stopper  52  is formed to be a cylindrical body having a diameter  54  that is generally smaller than the diameter of the opening  26  of the tube  12 . The stopper  52  also includes an annular slot (not shown) to receive a deformable seal  58 , such as an o-ring. The seal  58  operatively deforms when the stopper  52  is inserted into the opening  26  of the tube  12  to create a seal between the tube  12  and the stopper  52 . However, it is contemplated other deformable seals  58  such as gaskets may be used to form the seal between the stopper  52  and the tube  12 .  
         [0018]    As shown in FIG. 3, the handle  40  is formed on the opposite side of the disk-shaped member  50  as the stopper  52  is formed on. The handle  40  is generally formed to include an aperture  62  to allow a portion of the user&#39;s hand to grasp the handle  40  and remove or insert the indicator  16  in the tube  12 . It is appreciated that the handle  40  may be formed in a variety of different ergonomic configurations and allow for insertion and removal of the indicator  16 .  
         [0019]    The locking mechanism  38  generally includes a first end  66  and a second end  68  defined by a pivotal connection  70  to the disk-shaped member  50  of the main body portion  36 . The pivotal connection  70  is shown to be a flexible member connecting the locking mechanism  38  to the main body portion  36  to allow for rotation of the locking mechanism  38  around an axis. The pivotal connection  70  is formed to be a unitary structure interconnecting the locking mechanism  38  and the main body portion  36 . The pivotal connection  70  allows elastic deformation to retain the locking mechanism in a desired position. It is appreciated that the pivotal connection may be formed of several elements such as a pin and a biasing member. The first end  66  includes locking tab  72  allowing positive engagement with a portion of the flange  28  of the tube  12 . The locking tab  72  includes a guide surface  74  and a locking surface  76 . The guide surface  74  is oriented at an angle to allow the locking tab  72  to actuate over the edge of the flange  28  of the tube  12 . Once the guide surface  74  articulates over the edge of the flange  28 , the locking surface  76  engages the flange  28  to prevent axial movement of the indicator  16  in direction A. The locking surface  76  is adapted to engage the engagement surface of the flange  28  of the tube  12 . The locking surface  76  is generally formed to be perpendicular to the engagement surface  30  to allow for increased contact area between the locking tab  72  and the flange  28  of the tube  12 . The pivotal connection  70  interconnects the engagement mechanism  30  and the main body portion  36  and allows the first end  66  to actuate the locking tab  72 .  
         [0020]    The second end  68  of the engagement mechanism  30  generally includes a lever  78  that is operable by at least one of the user&#39;s fingers. The lever  78  is preferably positioned to allow the user to grasp the handle  40  with a portion of the handle  40  and to actuate the lever  78  with one finger.  
         [0021]    In operation, the indicator  16  is inserted into the tube  12  by grasping the handle  40  and actuating the lever  78  of the engagement mechanism  38  inward, thus forcing the locking member tab  72  outward from the flange  28 . The measuring rod  34  of the indicator  16  is then inserted in the tube  12  and the main body member  36  of the indicator  16  is moved closer to the flange  28  of the tube  12 . When the disk-shaped portion  50  of the indicator  16  abuts the flange  28 , the lever  78  of the engagement mechanism  38  is released and the locking surface  76  of the locking tab  72  contacts the engagement surface  30  of the flange  28 .  
         [0022]    To remove the indicator  16  from the tube  12 , the handle  40  is grasped by some of the user&#39;s fingers and the lever  78  of the engagement mechanism  38  is actuated inward by at least one of the user&#39;s other fingers. Once the lever  78  is actuated inward, the indicator  16  is withdrawn from the tube  12  to allow the level of the fluid  18  to be checked by the user.  
         [0023]    The description of the invention is merely exemplary in nature and, thus, variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the invention.