Reversible volume oil pump

Information

  • Patent Grant
  • 6461117
  • Patent Number
    6,461,117
  • Date Filed
    Tuesday, February 27, 2001
    23 years ago
  • Date Issued
    Tuesday, October 8, 2002
    22 years ago
Abstract
A fluid pump is provided that produces an outflow of fluid that is not proportional to the speed of the input drive. Thus, the fluid pump can be tuned to provide a substantially constant outflow of fluid irrespective of the speed of the input drive. The fluid pump also provides fluid outflow when the rotational direction of the input drive is reversed.
Description




FIELD OF THE INVENTION




The present invention relates generally to fluid pumps, and particularly, to a lubrication pump capable of providing a substantially constant outflow of fluid.




BACKGROUND




As is well-known to those skilled in the art of automotive vehicle, but also known by those in other arts, mechanical assemblies often require fluid lubrication for optimal performance and reliability. Typical examples where this need for lubrication is especially important in automotive vehicles include piston engines, transmissions, and other drivetrain components. Commonly, lubrication is provided to these components with a fluid pump that produces an outflow of fluid from a fluid reservoir. The outflow of fluid is then directed throughout the component that requires lubrication by a number of narrow passages or hoses.




To optimize lubrication, the fluid is often routed directly to critical friction surfaces within the component. Typically, these critical friction surfaces involve mating metal surfaces that slide against each other under high speed or high load. A common example of a critical friction surface that requires lubrication is the journal and bearing surface of a rotating bearing. Lubrication of moving parts generally provides two benefits. First, the fluid minimizes wear between the moving parts, thus lengthening the operating life of the component and also increasing efficiency of the component. Second, the fluid absorbs heat that is generated by the friction between the moving parts, thus dissipating the heat away from the moving parts and cooling the component. As is well-known by those in the art, a variety of fluids can be used to lubricate critical friction surfaces, and the choice is usually influenced by a number of different design considerations. Petrochemical oils with varying viscosities are commonly used for lubrication and are satisfactory for many applications. One example of a well-known and often used lubricant is automatic transmission fluid, or also referred to as Dextron II.




Traditionally, lubrication of automotive vehicle components has been provided by mechanically driven fluid pumps. Accordingly, the fluid pump is usually mounted directly to or close by the drivetrain component, and power is provided to the pump from rotating drive members in the component. A variety of drive systems have been employed to power lubrication fluid pumps, with one common example including an input drive shaft that extends into the fluid pump and a gear from the drivetrain component that drives the input drive shaft.




One characteristic of mechanically driven fluid pumps is that the volume of fluid outflow from the pump usually varies as the speed of the input drive shaft varies. Thus, as the speed of the drive gear from the component increases (and consequently the speed of the input drive shaft increases), the volume of fluid flowing from the pump will increase. Similarly, as the speed of the component decreases, the outflow from the pump also decreases. Thus, a proportional relationship generally exists between the speed of the component and the outflow of fluid from the pump.




Usually, this variation in outflow from the pump does not present any significant problems to the performance of an automotive vehicle. Typically, the engine in an automotive vehicle operates within a relatively narrow range of rotational speeds. Thus, the maximum speed of the engine is often about 3,000 rpm and the slowest speed of the engine is about 500 rpm when the engine is idling. The rotational speed of the drivetrain components are likewise relatively narrow. Therefore, because the speed of the input drive shaft for the fluid pump varies within a relatively narrow range, the resulting variation in lubricating fluid flow is also minimal. This limited variation in lubricating fluid flow generally has few adverse effects on the drivetrain components because a range of flow volume is acceptable.




However in some lubricating systems, a proportional relationship between component speed and pump outflow is unsatisfactory. One such example involves electric motor driven drivetrains. In these systems the electric motor can operate at much faster speeds than traditional drivetrain components. In addition, the electric motor can operate at very low speeds below the traditional 500 rpm idling speed, including speeds nearing zero rpm. In these types of drivetrains, the normal variation in outflow from a traditional fluid pump is too large to provide acceptable lubrication of the drivetrain components. The problem is especially acute at low speeds, where the outflow of fluid from a traditional pump is reduced significantly and approaches zero as the electric motor nears zero rpm. In contrast, the electric motor in these systems tends to operate at its worst efficiency and generates the most heat at low speeds. Thus, in drivetrains where the fluid pump is used to lubricate and cool the electric motor in addition to other drivetrain components, a traditional fluid pump is inadequate to provide acceptable fluid flow.




Another problem with mechanically driven fluid pumps is the inability to provide fluid outflow when the rotational direction of the input drive shaft reverses. This is generally not a problem with piston engine drivetrains because the major drivetrain components always rotate in the same direction and never reverse their direction of rotation. However, when an electric motor is used in the drivetrain, the rotational direction of the drivetrain components can easily be reversed by simply switching the direction of rotation of the electric motor through its logic controller. Thus, traditional fluid pumps are also inadequate for electric motor drivetrains because they do not provide lubrication fluid when the electric motor reverses direction.




One alternative to a traditional mechanically driven fluid pump is an electric powered fluid pump. In this alternative, the electrical system of the automotive vehicle supplies power to the fluid pump. The pump and the resulting outflow of fluid can then be controlled by a logic controller. Thus, the fluid outflow can be controlled irrespective of the speed or direction of rotation of the drivetrain. Accordingly, the volume of fluid outflow from the pump can be maintained at a substantially constant volume throughout the entire range of drivetrain component speeds. The electric pump is also unaffected by the rotational direction of the drivetrain, and thus lubrication fluid can be provided when the drivetrain is operated in a reverse direction.




Several problems exist with electric pumps however. Electric pumps generally operate less efficiently than mechanically driven fluid pumps. For example, in mechanically driven pumps the drive system is often about 96% efficient in providing power to the pumping assembly. On the other hand, an electric drive system is usually only about 80% efficient in providing power to the pumping assembly. Electric pumps are also usually less reliable than mechanically driven pumps during the operating life of the automotive vehicle. This lower reliability typically occurs because electric pumps are more complicated, thus providing more potential sources of failures. Electric pumps are also the source of more failures because the electric pump is usually mounted to the chassis of the automotive vehicle and is connected to the drivetrain components with fluid hoses and electrical wiring. As a result, these extra hoses and wires become susceptible to damage from being town, worn or cut. In contrast, mechanically driven pumps are often designed to be integral with a drivetrain component, making excess hoses and wires unnecessary. In addition, another problem with electric pumps is the difficulty of designing an electric pump into the electrical system of an automotive vehicle. Typically, automotive vehicles are provided with a 12V electrical system to power a variety of accessories. If an electric motor drivetrain is used in the automotive vehicle, another higher voltage electrical system may be provided for the electric motor. However, the electric pump is not always easily designed into either of these electrical systems because of load and efficiency considerations. One final problem with electric pumps is their cost, which is usually higher in automotive vehicles than mechanical pumps. As is well-known, automotive vehicles are typically produced by manufacturers in high volumes. As a result, mechanically driven pumps are usually less expensive since the capital cost of designing a specially adapted pump can be averaged across a large number of vehicles.




SUMMARY




Accordingly, a mechanically driven fluid pump is provided for producing a fluid outflow that is not proportional to the speed of the input drive. The pump includes a control valve that directs some of the fluid from the pump assembly to an outflow port and some of the fluid to a diversion port. As the speed of the input drive charges, the position of the valve is altered, thus altering the proportion of fluid directed to the outflow and diversion ports. A mechanical governor that applies centrifugal force to swing arms can be used to alter the position of the control valve proportionately to the speed of the input drive.




Two embodiments of a pump assembly are provided with both embodiments capable of producing fluid flow when the rotational direction of the input drive is reversed. One embodiment is an impeller pump assembly that includes an impeller with forward and reverse impeller sections. When the input drive rotates, one of the impeller sections is sealed by a dividing plate, thus producing fluid flow from one of the impeller sections. Another embodiment is a cam piston pump assembly. The cam piston pump assembly includes a cam attached to the input shaft and a pushrod biased against the cam. The pushrod reciprocates a piston which forces fluid through a control valve.











BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS




The invention, including its construction and method of operation, is illustrated more or less diagrammatically in the drawings, in which:





FIG. 1

is a cross-sectional view of an impeller pump, showing an input drive, an impeller pump assembly, a governor and a control valve; and





FIG. 2

is a cross-sectional view of a cam piston pump, showing an input drive, a cam piston pump assembly, a governor and a control valve.











DETAILED DESCRIPTION OF THE INVENTION




Referring now to the drawings, two embodiments are provided of a fluid pump


10


,


100


for lubricating drivetrain components


2


in automotive vehicles or other such applications. The first embodiment, shown in

FIG. 1

, employs an impeller pump assembly


20


to provide fluid flow through the pump


10


. In comparison, the second embodiment, shown in

FIG. 2

, employs a cam piston pump assembly


110


to provide the fluid flow. Both pumps


10


,


100


are capable of providing a substantially constant outflow of fluid from the pump


10


,


100


irrespective of variations in the speed of the input drive


12


. Additionally, the pumps


10


,


100


can provide fluid outflow when the input drive


12


is rotated in either a forward or reverse direction. Thus, the first and second embodiments demonstrate a wide breadth of the present invention.




Turning to

FIG. 1

, the impeller pump


10


includes an input drive


12


. Various input drives are possible, but the preferred embodiment uses a drive gear


14


, a driven gear


16


, and an input shaft


18


. Preferably, the drive gear


14


is a power transmission gear that is integral with the drivetrain component


2


that is lubricated by the pump


10


. Typically, the rotational speed of the drive gear


14


will vary within a range as the speed of the drivetrain component


2


varies. These speed variations may include speeds approaching zero rpm. The drive gear


14


may also rotate in either a forward direction or a reverse direction (i.e. clockwise or counterclockwise). In some applications the drive gear


14


is connected either directly or indirectly to an electric drive motor, thus making large variations in rotational speed possible and making reversals in the rotational direction likely. The gear teeth of the drive gear


14


enmesh with the gear teeth of the driven gear


16


so that when the drive gear


14


rotates, the driven gear


16


rotates responsively. The input shaft


18


is fixedly attached to the driven gear


16


so that it also rotates responsively as the driven gear


16


rotates.




The input shaft


18


extends into the pump


10


and through the impeller pump assembly


20


and the mechanical governor assembly


50


. The input shaft


18


is rotationally mounted within the housing assembly


4


,


5


by tapered roller bearings


22


. Thus, one tapered roller bearing


22


is mounted on one side of the pump assembly


20


and another tapered roller bearing


22


is mounted on the other side of the pump assembly


20


. The tapered roller bearings


22


are matched and appropriately mounted to resist thrust forces that are generated by the impeller pump assembly


20


. The fluid in the pump assembly


20


is sealed from the input drive


12


and the governor assembly


50


by seals


24


that are mounted onto the input shaft


18


adjacent to the outside of each of the tapered roller bearings


22


. Therefore, the tapered roller bearings


22


are lubricated by the fluid that flows through the pump assembly


20


. The drive gear


14


and driven gear


16


are also preferably lubricated with a fluid, but the seal


24


between the pump assembly


20


and the input drive


12


allows a different type of fluid to be used if so desired. The governor assembly


50


is also preferably lubricated. However, a grease-type lubricant is preferable and can be applied a single time during assembly of the pump


20


. The seal


24


between the pump assembly


20


and the governor assembly


50


prevents fluid from entering the governor assembly


50


.




The input shaft


18


also includes a long-pitch thread section


26


that is positioned across the length of the pump cavity


28


. Various thread designs are possible but a thread


26


with about one thread revolution per inch is preferable. The thread


26


is illustrated in

FIG. 1

as a hidden, helical line on the input shaft


18


. A pair of snap rings


30


are also mounted onto the input shaft, with one snap ring


30


positioned on each side of the impeller


32


. The snap rings


30


are positioned so that the inside surfaces of the snap rings


30


are located slightly within the pump cavity


28


. Accordingly, the snap rings


30


stop the movement of the impeller


32


as it travels along the thread


26


when one side of the impeller


32


abuts against either of the snap rings


30


. However, many other types of stops may also be used to limit the travel of the impeller


32


.




Preferably, the impeller


32


is a single piece unit and may be made from die cast aluminum. The impeller


32


includes a forward impeller section


34


and a reverse impeller section


36


. Accordingly, the forward impeller section


34


has impeller blades


35


facing in one direction, and the reverse impeller section


36


has impeller blades


37


facing in the opposite direction. The two impeller sections


34


,


36


are separated by a dividing plate


38


that blocks fluid flow between the impeller blades


35


,


37


of the two sections


34


,


36


. The dividing plate


38


also extends outward from the outer diameter of the impeller sections


34


,


36


.




The impeller


32


also includes an inner bore (not indicated) that extends through the impeller


32


. The diameter of the inner bore mates with the diameter of the input shaft


18


so that the impeller


32


readily slides laterally along the input shaft


18


. The inner bore also includes a mating thread


26


to the long-pitch thread


26


of the input shaft


18


. Accordingly, the impeller


32


is threaded onto the thread


26


of the input shaft


18


, thus allowing the impeller


32


to move laterally along the input shaft


18


as the impeller


32


rotates about the long-pitch threads


26


. Matching springs


40


are provided to counter this movement of the impeller


32


. One of the springs


40


is. mounted between each side of the impeller


32


and the corresponding side of the pump housing


4


,


5


. Accordingly, each of the springs


40


apply a force against opposite sides of the impeller


32


and against each other


40


, thereby centering the impeller


32


within the pump cavity


28


.




The operation of the impeller pump assembly


20


is now apparent. When the drive gear


14


is not moving and the pump


10


is at rest, the impeller


32


is forced to the center of the pump cavity


28


by the springs


40


. However, when the drive gear


14


begins to rotate in a forward direction, inertia and resistance from the fluid on the impeller blades


35


,


37


cause the impeller


32


to rotate, or spin, on the input shaft


18


. As the impeller


32


rotates on the input shaft


18


, the impeller


32


overcomes the small bias provided by the springs


40


and travels along the long pitch threads


26


toward the reverse side sealing surfaces


43


. The movement of the impeller


32


is stopped by one of the snap rings


30


when the dividing plate


38


is positioned near to but not touching the reverse side sealing surfaces


43


. The reverse impeller section


36


is now sealed from the reservoir


9


and the control valve


70


, thus preventing the reverse facing impeller blades


37


from pumping fluid. Accordingly, the forward facing impeller blades


35


pump fluid through the pump assembly


20


from the reservoir


9


to the control valve


70


. Similarly, when the drive gear


14


begins to rotate in the reverse direction, an opposite sequence of events occurs. Instead of traveling toward the reverse sealing surfaces


43


, the impeller


32


follows the long-pitch threads


26


toward the forward sealing surfaces


42


until the impeller


32


abuts and stops against the other snap ring


30


, thus sealing the forward impeller section


34


. Because the reverse impeller blades


37


face in the opposite direction of the forward impeller blades


35


, the reverse impeller section


36


pumps fluid through the pump assembly


20


while the input shaft


18


rotates in reverse. Thus, regardless of the direction of rotation of the drive gear


14


, the impeller


32


provides fluid flow through the pump


10


.




The volume of fluid flow through the pump assembly


10


, however, is generally proportional to the speed of drive gear


14


. Therefore, a mechanical governor assembly


50


and a control valve


70


are provided to reduce the variation of fluid flow volume through the pump assembly


20


. The governor


50


includes a pair of first swing arms


52


that are pivotally attached at a first end


53


to the input shaft


18


. The second end


54


of the first swing arms


52


is pivotally attached to a second end


54


of a second pair of swing arms


56


. The second swing arm


56


is then pivotally attached at a first end


57


to a sleeve


58


. The sleeve


58


includes an inner bore


59


that is sized to easily slide along the input shaft


18


. The sleeve


58


also includes a slot


60


along the exterior of the sleeve


58


. A piston


62


, or drive member


62


, is installed within the slot


60


and is installed within a guide diameter


63


in the pump housing


6


. The piston


62


is also pivotally connected to one end of a lever


64


. The other end of the lever


64


is pivotally connected to a pushrod


66


, and a midpoint of the lever


64


is pivotally attached to the pump housing


5


.




The pushrod


66


is pivotally connected to the spool


72


of the control valve


70


. The spool


72


includes two passages


74


,


76


that extend through the spool


72


. One passage is an outflow passage


74


that is straight and connects the pump assembly


20


to the outflow port


75


of the pump


10


. The other passage is a diversion passage


76


that is angled and connects the pump assembly


20


to the diversion port


77


. The control valve


70


also includes a spring


78


that is retained between the spool


72


and a snap ring


80


attached to the pump housing


5


. Thus, the spring


78


forces the spool


72


away from the snap ring


80


. An O-ring seal


82


is also provided which prevents fluid from leaking through the control valve


70


and entering the governor


50


.




Accordingly, the manner in which the governor


50


and the control valve


70


compensate for the variable fluid flow through the pump assembly


20


is now apparent. When the drive gear


14


is not moving and the pump


10


is at rest, the spring


78


in the control valve


70


biases the spool


72


so that the entire outflow passage


74


connects the pump assembly


20


to the outflow port


75


. At this stage, the diversion passage


76


is biased away from the pump assembly


20


, thus preventing fluid from flowing to the diversion port


77


.




However, when the drive gear


14


begins to rotate, centrifugal force is generated and applied to the swing arms


52


,


56


, which pulls the second ends


54


of the swing arms


52


,


56


outward. As the swing arms


52


,


56


are forced outward, the swing arms


52


,


56


pull the sleeve


58


toward the first end


53


of the first swing arms


52


. Correspondingly, the piston


62


also moves towards the first end


53


of the first swing arms


52


, and the lever


64


rotates about its midpoint. The spool


72


is then forced against the spring


78


so that the diversion passage


76


moves toward the pump assembly


20


.




As is readily understood, an increasing amount of centrifugal force is applied to the swing arms


52


,


56


as the speed of the dive gear


14


increases, thus causing the spool


72


to move the diversion passage


76


proportionately further toward the pump assembly


20


. The outflow passage


74


and the diversion passage


76


are positioned sufficiently close to each other so that when the drive gear


14


reaches a particular speed, the pump assembly


20


will be connected to both passages


74


,


76


simultaneously. Therefore, some of the fluid flow will pass to the outflow port


75


and some of the fluid flow will pass to the diversion port


77


. As the speed of the driving gear


14


increases, the diversion passage


76


becomes increasingly more connected to the pump assembly


20


. As a result, the control valve


70


progressively provides less fluid flow to the outflow port


75


and more fluid to the diversion port


77


.




By tuning the governor assembly


50


and the control valve


70


, the desired volume of fluid outflow from the pump


10


can be achieved. Preferably, the desired outflow will be substantially constant irrespective of the speed of the drive gear


14


. Tuning will generally involve adjustments to the size and spacing of the passages


74


,


76


in the spool


72


and the inertia of the swing arms


52


,


56


. Additionally, a pressure regulating device Knot shown) such as an orifice or valve, may be desirable in the diversion port


77


to adjust the fluid pressure that is provided to the outflow port


75


. These tunings and others that may be necessary are all within the normal skill of those in the art and will depend on the particular application of the pump


10


and the desired fluid flow characteristics.




Preferably, the pump


10


is designed to be an integral assembly with the drivetrain component


2


that requires lubrication. Thus, the pump


10


can be directly mounted to the component


2


. Instead of an outflow port


75


, the outflow port


75


may also be a series of internal passages that directly connect the outflowing fluid to the desired lubricating areas. Likewise, the diversion port


77


may be a series of internal passages that eventually return the fluid to the reservoir


9


. However, the outflow port


75


is preferably connected to a heat exchanger that cools the fluid before returning the fluid to the reservoir


9


. To ease assembly of the pump


10


, the pump housing


4


,


5


,


6


may also include multiple housings that are connected together during assembly of the pump


10


. Thus, in the desired embodiment, three housing


4


,


5


,


6


are employed.




Turning now to FIG.


2


and the second embodiment, a fluid pump


100


with a cam piston pump assembly


110


is provided. The cam piston pump


100


is similar to the impeller pump


10


described above; therefore the input drive


12


, governor assembly


50


and control valve


70


do not need to be described further since their functions are generally the same as in the impeller pump


10


. In the cam piston pump


100


, the pump assembly


110


, which was represented by the impeller pump assembly


20


in the impeller pump


10


, includes a cam


112


and a piston


120


.




Accordingly, a cam


112


is fixedly attached to the input shaft


18


. The cam contacts a roller


114


that is pivotally attached to a pushrod


116


. The pushrod


116


is installed in a bore (not indicated) that allows the pushrod


116


to freely move up and down. However, a spring


118


is installed below the pushrod


116


to bias the pushrod


116


and roller


114


against the cam


112


. The pushrod


116


also includes a piston


120


at the bottom end of the pushrod


116


.




Fluid is routed from the reservoir


9


to the piston


1


:


20


through internal passages


102


,


104


. Preferably, the first passage


102


is connected to the pump assembly


110


to provide lubrication to the cam


112


and pushrod


116


. As with the impeller pump


10


, seals


24


are preferably provided on the outside of the bearings


106


to prevent fluid from entering the governor


50


and the input drive


12


. Unlike the impeller pump


10


, the bearings


106


may be roller ball bearings


106


instead of tapered roller bearings


22


since little thrust is expected from the pump assembly


20


. However, tapered roller bearings can be used in a particular application if the thrust generated by the governor


50


exceeds the capacity of the roller ball bearings


106


.




The fluid proceeds through a second passage


104


to the piston


120


. For manufacturing purposes, the lower portion


105


of the second passage


104


is drilled through the side of the pump housing


4


,


5


. Therefore, a plug


108


is installed into the outside portion of the passage


104


to block the end of the second passage


104


. Installed below the piston


120


is a check valve


122


. The check valve


122


includes an orifice


124


and a ball


126


that is forced against the orifice


124


by a spring


128


.




Accordingly, the operation of the cam piston pump


100


it now apparent. As the Input shaft


18


rotates, the cam


112


alternatively forces the pushrod


116


down, with the spring


118


biasing the pushrod up, so that the piston


120


reciprocates between up and down positions. As a result, when the pushrod


116


is in its upward position, the piston


120


is positioned above the lower portion


105


of the passage


104


. However, when the pushrod


116


moves to its downward position, the piston


120


travels through the lower portion


105


of the passage


104


, thereby forcing fluid down into the check valve


122


. The fluid then passes through the orifice


124


and forces the ball


126


down against the spring


128


, thus allowing the fluid to pass to the control valve


70


. Once the fluid passes through the check valve


122


, the piston


120


returns to its upward position and the valve


126


is forced back against the orifice


124


to prevent the fluid from passing back up to the lower portion


105


of the second passage


104


.




It can be readily seen, therefore, that the piston


120


pumps fluid to the control valve


70


regardless of the rotational direction of the input shaft


18


because the cam


112


reciprocates the pushrod


116


up and down in both forward and reverse speeds. Like the impeller pump


32


, however, the volume of fluid flow from the cam piston pump assembly


110


varies proportionately with the speed of the drive gear


14


. Therefore, the governor assembly


50


and the control valve


70


compensate for this variation as described above. Thus, by tuning the governor


50


and the control valve


70


, a desired outflow of fluid from the pump


100


can be accomplished. Preferably, this outflow is substantially constant irrespective of the speed of the drive gear


14


.




While a preferred embodiment of the invention has been described, it should be understood that the invention is not so limited, and modifications may be made without departing from the invention. The scope of the invention is defined by the appended claims, and all devices that come within the meaning of the claims, either literally or by equivalence, are intended to be embraced therein.



Claims
  • 1. A fluid pump comprising a pump assembly generating a volume of fluid flow from a reservoir, said pump assembly being powered by an input drive; and a control valve disposed between said pump assembly and an outflow, wherein said control valve diverts to a diversion a portion of said volume directed to said outflow when speed of said input drive is changed; and a governor, wherein said governor alters a position of said control valve when said speed of said input drive is changed.
  • 2. The fluid pump according to claim 1, further comprising a diversion, wherein said control valve alters a portion of said volume directed to said diversion in response to said portion directed to said outflow.
  • 3. The fluid pump according to claim 2, further comprising an outflow passage extending through said control valve and a diversion passage extending through said control valve, said outflow passage being disposed to connect said pump assembly to said outflow and said diversion passage being disposed to connect said pump assembly to said diversion; wherein said control valve alters said outflow passage connection and said diversion passage connection thereby proportionately altering said portions directed to said outflow and said diversion.
  • 4. The fluid pump according to claim 1, wherein said governor is a mechanical governor.
  • 5. The fluid pump according to claim 4, wherein said portion of said volume directed to said outflow is substantially constant irrespective of said speed of said input drive.
  • 6. The fluid pump according to claim 4, wherein said governor comprises swing arms pivotally attached to an input shaft of said input drive, wherein centrifugal force influences said swing arms when said speed of said input drive is changed thereby altering said position of said control valve.
  • 7. The fluid pump according to claim 6, further comprising a spring biasing against said centrifugal force.
  • 8. The fluid pump according to claim 7, wherein said swing arms are further pivotally attached to a rotating sleeve, said sleeve being engaged by a non-rotating drive member connected to said control valve.
  • 9. The fluid pump according to claim 8, wherein said sleeve includes a slot and said drive member is disposed within said slot; and wherein said drive member is pivotally connected to a lever, said lever being pivotally connected to a housing and pivotally connected to a pushrod, said pushrod being pivotally connected to said control valve.
  • 10. The fluid pump according to claim 3, wherein said input drive comprises a drive gear from a drivetrain component, said drive gear being enmeshed with a driven gear fixedly attached to an input shaft, said input shaft thereby rotatably powering said pump.
  • 11. The fluid pump according to claim 3, wherein said pump assembly generates said volume of fluid flow regardless of a rotational direction of said drive input.
  • 12. The fluid pump according to claim 11, wherein said pump assembly is a cam piston pump assembly.
  • 13. The fluid pump according to claim 12, wherein said input drive comprises an input shaft rotatably powering said pump assembly; and wherein said pump assembly comprises a cam attached to said input shaft, a pushrod being biased against said cam, and a piston being attached to said pushrod; said piston thereby generating said volume of fluid flow.
  • 14. The fluid pump according to claim 13, wherein said piston reciprocates through a passage filled with fluid from said reservoir thereby forcing fluid to said control valve.
  • 15. The fluid pump according to claim 14, wherein said pump assembly comprises a check valve disposed between said passage and said control valve thereby preventing said forced fluid from returning to said passage when said piston reciprocates.
  • 16. The fluid pump according to claim 15, wherein said reservoir is connected to said cam and said pushrod thereby lubricating said cam and said pushrod.
  • 17. The fluid pump according to claim 16, wherein said pump assembly comprises roller ball bearings and seals mounted on said input shaft on opposite sides of said cam, said bearings being disposed between said cam and said seals.
  • 18. The fluid pump according to claim 3, further comprising a mechanical governor, wherein said governor alters a position of said control valve when said speed of said input drive is changed; and wherein said pump assembly is a cam piston pump assembly, said pump assembly generating said volume of fluid flow regardless of a rotational direction of said drive input, wherein said input drive comprises an input shaft rotatably powering said pump assembly, and wherein said pump assembly comprises a cam attached to said input shaft, a pushrod being biased against said cam, and a piston being attached to said pushrod, said piston thereby generating said volume of fluid flow.
  • 19. The fluid pump according to claim 18, wherein said piston reciprocates through a passage filled with fluid from said reservoir thereby forcing fluid to said control valve, said pump assembly comprising a check valve disposed between said passage and said control valve thereby preventing said forced fluid from returning to said passage when said piston reciprocates.
  • 20. The fluid pump according to claim 19, wherein said governor comprises swing arms pivotally attached to said input shaft of said input drive, wherein centrifugal force influences said swing arms when said speed of said input drive is changed thereby altering said position of said control valve, wherein a spring biases against said centrifugal force, said swing arms being further pivotally attached to a rotating sleeve, said sleeve being en(gaged by a non-rotating drive member connected to said control valve.
  • 21. The fluid pump according to claim 20, wherein said portion of said volume directed to said outflow is substantially constant irrespective of said speed of said input drive.
  • 22. The fluid pump according to claim 20, wherein said input drive comprises a drive gear from a drivetrain component, said drive gear enmeshed with a driven gear fixedly attached to said input shaft, said input shaft thereby rotatably powering said pump.
  • 23. A fluid pump comprising a pump assembly rotatable attached to an input shaft, said pump assembly generating a volume of fluid flow from a reservoir proportional to a speed of said input shaft; and a governor altering the position of a control valve proportionately to said speed of said input shaft, said control valve directing a portion of said volume of fluid flow to an outflow and another portion to a diversion; wherein said outflow portion decreases as said speed of said input shaft increases.
  • 24. The fluid pump according to claim 23, wherein said pump assembly generates said volume regardless of a rotational direction of said input shaft.
  • 25. The fluid pump according to claim 24, wherein said outflow portion is substantially constant irrespective of said speed of said input shaft.
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