Abstract:
The present invention relates to the oil pump, and can be used with a standard pump jack. The pump can be used to withdraw any type of fluid, including water for example. Certain aspects of the invention relate to a method and apparatus for efficiently converting the up and down motion of the pump jack into a reliable vacuum source which can reliably pull unrefined/crude oil from the first depth to the second depth.

Description:
CROSS REFERENCES 
       [0001]    This application is continuation in part of U.S. Pat. No. 11/122,086 filed May 5, 2005 which claims the benefit of priority to U.S. 60/568,233 filed May 6, 2004; both applications are incorporated by reference in their entirety. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    The present invention relates to pumps for pulling fluids from a first depth to a second depth. One of the preferred embodiments of the invention is a pump which can pull oil from a first depth and raise the oil to a second depth. 
       SUMMARY OF THE INVENTION 
       [0003]    The present invention relates to a fluid pump, and can be used with a standard pump jack. The pump jack provides the +/−Z motion (up and down) which drives power to the pump to pull fluid from a first depth to a second depth (e.g. from the ground to an oil collection port). Certain aspects of the invention relate to a method and apparatus for efficiently converting the up and down motion of the pump jack into a vacuum source which can reliably pull unrefined/crude oil or other fluid from a first depth to a second depth. 
     
    
     
       BRIEF DESCRIPTION OF THE INVENTION 
         [0004]      FIG. 1  illustrates a pump jack. 
           [0005]      FIGS. 2A-2D  illustrates a schematic of the pump. 
           [0006]      FIG. 3  is a cross section of the pump. 
           [0007]      FIG. 4  is a perspective view of the cap. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0008]    Although not shown in  FIG. 2 , when deployed for usage, pump  10  would be connected to a standard pump jack  1  ( FIG. 1 ). A pump jack  1  and a pump ( FIG. 2 ) can be used together to withdraw fluid from the ground. When deployed, pump  10  can be placed inside a bore  2  or hole in the ground. 
         [0009]      FIGS. 2 and 3  illustrate differently the same basic aspects of the invention, and the use of two sets of figures is intended to better illustrate how certain embodiments of the invention work. Note  FIG. 3  has some additional structural details (such as the cap) which will be explained separately. 
         [0010]    As shown in  FIG. 2 , one embodiment of the invention features a housing forming an upper chamber  21  and a lower chamber  22 . Oil or water (denoted by the wavy lines at the bottom) may be drawn through a filter (not shown) and into the lower intake valve  61 . As shown, tanks  30 A and  30 B contain a diaphragm  31 A and  31 B which is movable from a concave position ( FIG. 2A ) to a neutral position ( FIG. 2B ) to a convex position ( FIG. 2C ) back to a neutral position ( FIG. 2D ) in response to vertical movement of the rod  50  which can move from a lower position, middle position, and upper position. The tanks themselves contain a shell  33 A and  33 B (to the left of the diaphragm), the diaphragm itself, and shield  32 A and  32 B. With port  42 A and  42 B, pipe  41 , and hydraulic cylinder  40  filled with operational fluid (such as mineral oil), the diaphragm is drawn into the concave position ( FIG. 2A ) when the rod  50  is withdrawn from the hydraulic cylinder  40 . Since the hydraulic cylinder, pipe, tanks, and diaphragms form a fluid tight seal, withdrawing the rod  50  causes a vacuum in the hydraulic cylinder. Oil (or other fluid) in the lower fluid chamber  22  pushes on the diaphragm (by passing through holes  34  in shield  32 A and  32 B) as a result of the pressure difference on each side of the diaphragm. The shield&#39;s shape, size, and concavity are designed to stop the diaphragm from over expanding (becoming too convex), and in some embodiments the shield can determine the shape of the diaphragm in the convex position. Over expansion could cause dislodgment of the diaphragm or damage to the diaphragm. When the rod  50  is pulled or lifted upwards, fluid pressure in the lower fluid chamber  22  decreases with respect to the first or lower depth  3  to the second depth (e.g. upper chamber  21 ) or the surface of the ground  5 . This causes lower valve  61  to open and upper valve  62  to close. The vacuum caused by the movement of the diaphragm causes a fluid pulling force towards the displaced diaphragm. This effectively pulls plug  64  down towards the diaphragm and plug  63  up towards the diaphragm. Although  FIG. 2A  for example shows the plug as a circle, in three dimensions it would resemble a sphere. The plugs are constrained, by plug stopper  67  and  68  (such as a brimmed hole into which the plug fits) and a plug retainer  65  and  66  which limits the upwards movement of the plug (as shown, the plug retainer is can be a retaining wall.)  FIG. 2A  shows the rod  50  in the up position, diaphragms  31 A and  31 B in the concave position, valve  61  in the open position, and valve  62  in the closed position.  FIG. 2B  shows rod  50  in the middle position moving towards the down position, shows diaphragms in the neutral position moving towards the convex position, valve  61  moving towards the closed position (or in the partially closed position), and valve  63  moving towards the open position (or in the partially open position).  FIG. 2C  shows rod  50  in the down position, diaphragms in the convex position, valve  61  in the closed position, and valve  63  in the open position.  FIG. 2D  shows  50  in the middle position moving towards the up position, shows diaphragms in the neutral position moving towards the concave position, valve  61  moving towards the open position (or in the partially open position), and valve  63  moving towards the closed position (or in the partially closed position). Note, there are at least two fluids in this embodiment, the operational fluid compartment (containing the hydraulic cylinder, pipes  41 , and tanks  30 A and  30 B), and the target fluid (such as oil or water) which the pump is structured to move. The target fluid can be in chambers  21  and/or  22  (collectively the target fluid compartment) and passes through valves  61  and  62 . In preferred embodiments, the operational fluid compartment and target fluid compartment are hermetically sealed so as to prevent the mixing of fluids between the compartments. To simplify the illustration, the operational fluid compartment  48  and the target fluid compartment are illustrated in  FIG. 2C  which has all other labeling removed to avoid cluttering the figure. 
         [0011]    Moving back to  FIG. 2A , the amount of fluid brought into the lower chamber  22  will depend on the number of diaphragms, as well as the size of the diaphragm, and its concavity, as well as the shape and size of the shield. The fluid will remain in the lower chamber  22  until the rod  50  is pushed back down. Pushing the rod  50  down (by for example the pump jack  1 ) causes the working fluid to push against the diaphragms  31 A and  31 B changing them from a concave position to a convex position. The movement of the diaphragms causes an increase in the pressure of the fluid in the lower chamber  22 , which then pushes downwardly and upwardly (away from the diaphragm). The down pushing force causes the fluid to push valve  61  into a closed position, by moving plug  63  into plug receiver  67 . At the top of the lower chamber  22 , the fluid pressure opens valve  62  (moving plug or sphere  64  into an upwards position) allowing oil to escape into the upper chamber  22 . 
         [0012]    As is the case with the diaphragms and pipe, hydraulic cylinder  40  is impermeable to the target fluid, so the target fluid pools in the upper chamber  21 . When the rod  50  is pressed down (now for the second time) the upper valve is sucked into a closed position (because of the decrease in volume of the diaphragms) and the lower valve is sucked into an open position. This allows a second round of target fluid to enter the lower chamber  22  (the first round of target fluid cannot recede into the lower chamber  22  because it is blocked by the upper plug  64 .) Then the rod  50  is pushed down, pressurizing the working fluid, and forcing the upper plug into the opened position. Once open, the second round of fluid enters the upper chamber  21 . Target fluid may be removed from the upper chamber  21  simply by connecting a pipe  40  to the upper chamber  21  which extends to the surface port. The upper and lower valves may have the same, similar, or different structures. As shown in  FIG. 2A , upper and lower valves have substantially the same structure. 
         [0013]      FIG. 3  shows a similar view as compared to  FIG. 2B  (the diagrams are in the neutral position and the rod is in the middle position.) Target fluid can still fill the upper chamber  21 , but to balance the suction forces in the pump, the rod and hydraulic cylinder are positioned in the center of the upper chamber  21 .  FIG. 3  also illustrates spacer  70 , used to fix hydraulic cylinder  40  in place in the upper chamber  21 . Note, spacer  70  may be fitted with pores, holes, or inlets to allow oil to pass through the spacer box. Spacer  70  in three dimensions may resemble a cylinder with a through hole. The hydraulic cylinder would be placed within the through hole via threading or other engagement mechanisms. Cap  80  (also illustrated in  FIG. 4 ) may contain grooves to allow a handle to be placed on the pump  1  to lower the pump into the oil well. Because replacing the handle would be very difficult when the pump is in the well, cap  80  may be fitted with one or more J-hooks  85  for receiving a pin for lifting the pump out of the ground. Catcher  90  may be equipped with pins  95  that can slide into the J-hooks to lift the pump from the ground. Catcher  90  may be attached to other components above which retain the oil. Catcher  90  may also be linked with other rods above provide the up and down motion of rod  50 . One advantage of the catcher-cap-j-hook system is it allows a crane (or other upward movement device) the pump to be pulled out of the ground without installing a separate hook to pull up the pump, dissembling the pump, or enlarging the bore  2  within which the pump is located. 
         [0014]    The amount of operational fluid in the pump is important so that the diaphragms move inwardly when the rod is pulled up and outwardly when the rod is pushed down. Too little fluid, and the diaphragms will not move enough, too much fluid and the diaphragms will move too much and risk being damaged by over expansion (although the shields my help reduce this risk.) The amount of operational fluid to add the pump can be determined as follows. 
         [0015]    When the pump is being assembled, the ultimate variable that needs to be determined (V f ), the final or optimum volume (such as gallons or liters) of working fluid that must be fed into the hydraulic cylinder. V f  will equal the original amount of working fluid added (V jack ) plus the original amount of working fluid (V jack ) times the coefficient of volume expansion (C v ) of the oil times the change in temperature of the oil a t jack -t pump ) or Δt. V jack  is the volume of oil at the surface level (above ground or at the pump jack) at t jack . The temperature under the ground may be higher or lower, but is equal to V pump . Because the working fluid will expand or contract, the final volume of operational fluid (V f ) one has when it is added to the pump is the original amount added V pump +V pump *C V *Δt=V f . 
         [0016]    Typically, C v  will be known, and Δt can be measured with a temperature probe, but V o  needs to be determined, because the above formula allows you to determine the amount of operational fluid you will have assuming you have determined how much operational fluid to originally add (V pump ). In most cases, there is a range of volumes (V pump ) that will be acceptable provided it is not too much or too little. So to determine this range, we determine how much operational fluid is the minimum amount of fluid V min  and how much operational fluid is the maximum amount of fluid V max  and determine V pump  to be the range between the minimum and maximum amount. 
         [0017]    Minimum. The volume of the tank T v  (shell volume plus shield volume) is approximately equal to the volume of fluid in diaphragm when it is full expanded in the convex position. Assuming n number of tanks, n*T v =TT v  (total tank volume). The system also contains pipes and ports which have a total volume P v . The hydraulic cylinder has minimum volume H min  (when the rod is placed all the way into the cylinder, or to its maximum depth) and a maximum volume H max  when the rod is pulled all the way out (or to the highest position) in the cylinder. So the minimum amount of volume in the pump (V min ) is TT v +P v +H min =V min . V pump  must be greater than the V min  or the pump will not have enough fluid to push the diaphragms to the shields. 
         [0018]    Maximum. The maximum amount of fluid the pump can contain is TT v +P v +H max . Again, consider that the volume in the hydraulic cylinder changes depending on how far the rod  50  is within the cylinder  40 . The further down the rod  50  is, the more volume of the cylinder  40  the rod takes up. So the maximum volume the pump can have is total tank volume plus the pipe and port volume plus the maximum volume of the hydraulic cylinder. V max =TT v +P v +H max . H max  will equal the volume of the hydraulic cylinder minus rod volume in the hydraulic cylinder at the highest height of insertion (minimum insertion), see  FIG. 2A . H min  will equal the volume of the hydraulic cylinder minus the rod volume in the hydraulic cylinder at the lowest height of insertion (full insertion), see  FIG. 2C . 
         [0019]    Since V f =V pump +V o *C v *Δt or (factoring out V o ) V f =V pump (1+C v *Δt). Since V pump  is [V min , V max ] (meaning all the volumes from the V min  to V max ) V f=[V   min , V max ](1+C v *Δt). And so the final volume of fluid to add is more than V min     —     f (1+C v *Δt) but less than V max     —     f (1C v *Δt), wherein V min     —     f  is minimum amount of operational fluid with adjustment made for temperature, and V max     —     f  is maximum amount of operational fluid with adjustment made for temperature. V min  (minimum amount of operational fluid without adjustment for temperature) is TT v +P v +H min , and V max  (maximum amount of operational fluid without adjustment for temperature) is TT v +P v +H max . Filling the pump with an optimum amount of working fluid V f  provides more efficient movement of oil through the pump. 
         [0020]    The pump may be outfitted with an intake  100  or filter assembly near the bottom of the lower chamber  22 , and it may also contain a target fluid reservoir in or above upper chamber  21  for storing the target fluid. Other configurations of the invention are contemplated, and the invention should not be limited except as set forth in the claims.