FLUID PUMP

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

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

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

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

FIG. 1 illustrates a pump jack.

FIGS. 2A-2D illustrates a schematic of the pump.

FIG. 3 is a cross section of the pump.

FIG. 4 is a perspective view of the cap.

DETAILED DESCRIPTION OF THE INVENTION

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.

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.

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 30A and 30B contain a diaphragm 31A and 31B 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 33A and 33B (to the left of the diaphragm), the diaphragm itself, and shield 32A and 32B. With port 42A and 42B, 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 32A and 32B) as a result of the pressure difference on each side of the diaphragm. The shield'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 31A and 31B 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 30A and 30B), 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.

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 31A and 31B 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.

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.

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.

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.

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.

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.

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.

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.

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=[Vmin, 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.

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.

Claims

1. A pump for moving a target fluid from a first depth to a second depth and designed for use with a pump jack, said pump designed to fit within a bore in the ground, said pump comprising a upper chamber, lower chamber, operational fluid compartment, target fluid compartment, rod having a volume, hydraulic cylinder having a volume, pipe, tank, diaphragm, an intake, and an upper valve and lower valve:

a. said rod disposed within and slideable within the hydraulic cylinder;

b. said hydraulic cylinder, pipe and tank composing an operational fluid compartment containing operational fluid;

c. said hydraulic cylinder, pipe, and tank in fluid communication with each another and composing the operational fluid compartment;

d. said upper and lower chamber in fluid communication with each other and composing the target fluid compartment;

e. said operational fluid compartment containing a volume and operational fluid, and target fluid compartment design to store the target fluid;

f. said operational fluid causing the diaphragms to move from a concave position to a convex position when the rod is moved from an upper position to a lower position;

g. said upper valve moving from a closed position to an open position when the diaphragm is moved from a concave position to a convex position;

h. said lower valve moving from an open position to a closed position when the diaphragm is moved from a concave position to a convex position;

i. said target fluid providing a pushing force against the upper valve to move the valve from the closed position to the open position thereby allowing the target fluid to enter the upper chamber; and

j. said target fluid providing a pushing force against the lower valve to move the valve from the open position to the closed position thereby blocking the target fluid from entering the intake.

2. The pump of claim 1 wherein:

a. said operational fluid causing the diaphragms to move from a convex position to a concave position when the rod is moved from a lower position to an upper position;

b. said upper valve moving from an open position to a closed position when the diaphragm is moved from a convex position to a concave position;

c. said lower valve moving from a closed position to an open position when the diaphragm is moved from a convex position to a concave position;

d. said target fluid providing a suction force against the upper valve to move the valve from the open position to the closed position thereby preventing the target fluid from receding from the upper chamber into the lower chamber; and

e. said target fluid providing a suction force against the lower valve to move the valve from the closed position to the upper position thereby blocking the target fluid from entering the intake.

3. The pump of claim 1 wherein said upper and lower valve having substantially the same structure; and said lower chamber containing the lower valve, and said upper chamber containing the upper valve.

4. The pump of claim 1, wherein said tank comprises a shield, a shell, and the diaphragm, wherein the shield restricts how far the diaphragm can expand when it is filled with operational fluid.

5. The pump of claim 1 wherein said operation fluid compartment containing between a minimum amount and maximum amount of operational fluid, wherein the minimum amount of operation fluid is equal to the volume of operational fluid compartment with the rod fully inserted into the cylinder and accounting for a change in operational fluid expansion based on temperature at the pump jack and at the pump, and the maximum amount of operation fluid is equal to the volume of the operational fluid compartment volume with the rod minimally inserted and accounting for a change in operational fluid expansion based on temperature at the pump jack and at the pump.

6. The pump of claim 1 wherein said operation fluid compartment containing at least Vmin—f amount of operational fluid, but no more than Vmax—f amount of operational fluid, wherein Vmin—f equals (TTv+Pv+Hmin)(1+Cv*Δt) and Vmax—f equals (TTv+Pv+Hmax)(1+Cv*Δt), wherein TTv is total tank volume, Pv is total pipe volume, Hmin equals the cylinder volume minus the rod volume in the cylinder at the lowest height of insertion, Hmax equals the cylinder volume minus the rod volume in the cylinder at the highest point of insertion, Cv is a coefficient of operational fluid expansion, and Δt is equal to a change in temperature as measured at the hydraulic cylinder and temperature as measured at the pump jack.

7. The pump of claim 1, comprising a cap having a j-hook and a catcher comprising a pin, wherein the pin of the catcher slides into the j-hook to allow a crane to withdraw the pump from the ground without dissembling the pump, adding a separate hook to pull out the pump, or enlarging the bore.

8. A method for moving a target fluid from a first depth to a second depth for use with a pump jack, said method comprising the steps of:

a. providing a pump designed to be placed in a bore, said pump comprising a upper chamber, lower chamber, operational fluid compartment, target fluid compartment, rod having a volume, hydraulic cylinder having a volume, pipe, tank, diaphragm, an intake, and an upper valve and lower valve;

b. disposing said rod within the hydraulic cylinder;

c. placing operational fluid within said hydraulic cylinder, pipes and tank; said cylinder, pipes, and tank composing an operational fluid compartment having a volume;

d. placing target fluid within said upper and lower chamber;

e. moving the rod from an upper position to a lower position to cause the operational fluid to move the diaphragms from a concave position to a convex position;

f. moving said upper valve from a closed position to an open position by moving said diaphragm from a concave position to a convex position;

g. moving said lower valve from an open position to a closed position by moving said diaphragm from a concave position to a convex position;

h. providing a pushing force with the target fluid to move the upper valve from the closed position to the open position thereby allowing the target fluid to enter the upper chamber; and

i. providing a pushing force against the lower valve to move the valve from the open position to the closed position thereby blocking the target fluid from entering the intake.

9. The method of claim 8 wherein:

a. moving the rod from a lower position to an upper position to cause the operational fluid to move the diaphragms from a convex position to a concave position;

b. moving said upper valve from an open position to a closed position by moving the diaphragm from a convex position to a concave position;

c. moving said lower valve from a closed position to an open position by moving the diaphragm from a convex position to a concave position;

d. providing a suction force with the target fluid against the upper valve to move the valve from the open position to the closed position thereby preventing the target fluid from receding from the upper chamber into the lower chamber; and

e. providing a suction force with the target fluid against the lower valve to move the valve from the closed position to the upper position thereby blocking the target fluid from entering the intake.

10. The method of claim 8 wherein said upper and lower valve having substantially the same structure; and said lower chamber contains the lower valve, and said upper chamber contains the upper valve.

11. The method of claim 8 wherein said tank comprises a shield, a shell, and the diaphragm, wherein the shield restricts how far the diaphragm can expand when it is filled with operational fluid.

12. The method of claim 8 comprising the step of placing between a minimum amount and maximum amount of operational fluid into the operational fluid compartment, wherein the minimum amount of operation fluid is equal to the volume of operational fluid compartment with the rod fully inserted into the cylinder and accounting for a change in operational fluid expansion based on temperature at the pump jack and at the pump, and the maximum amount of operation fluid is the total operational fluid compartment volume with the rod minimally inserted and accounting for a change in operational fluid expansion based on temperature at the pump jack and at the pump.

13. The method of claim 8 comprising the step of placing between at least Vmin—f amount of operational fluid, but no more than Vmax—f amount of operational fluid in the operational fluid compartment, wherein Vmin—f equals (TTv+Pv+Hmin)(1+Cv*Δt) and Vmax—f equals (TTv+Pv+Hmax)(1+Cv*Δt), wherein TTv is total tank volume, Pv is total pipe volume, Hmin equals the cylinder volume minus the rod volume in the cylinder at the lowest height of insertion, Hmax equals the cylinder volume minus the rod volume in the cylinder at the highest point of insertion, Cv is a coefficient of operational fluid expansion, and Δt is equal to a change in temperature as measured at the hydraulic cylinder and temperature as measured at the pump jack.

14. The method of claim 8 comprising using a catcher having a pin to lock into a cap having a j-hook to withdraw the pump from the ground without dissembling the pump, adding a separate hook to pull out the pump, or enlarging the bore.