Patent Application
20210054840
The present disclosure relates generally to oil pumps and, for example, to an oil pump for an aged engine.
Internal combustion engines require lubricating systems to lubricate moving parts and to remove heat. In some internal combustion engines, a lubricating system may include an oil pump that distributes oil throughout the engine via one or more oil galleries, and a scavenge pump that collects spent oil and returns the spent oil to the oil pump for further distribution. Engines, and in particular engines used for heavy machinery, may experience low oil pressure later in service life. This low oil pressure is the result of the lubrication system lacking the capacity to meet increased oil flow demands created by engine wear over the life of the engine. Such low oil pressure conditions may negatively impact engine wear, engine cooling capacity, and overall engine performance.
While a larger capacity oil pump may be considered as a solution for increasing oil pressure in aged engines, this approach is often difficult in a retrofit application. In particular, increasing the capacity of the oil pump may cause the oil pump's capacity to reach or exceed the scavenge pump's capacity. When this occurs, the scavenge pump cannot return spent oil to the lubrication system at a rate that is sufficient to meet demands of the oil pump, thereby introducing air into the oil. In such cases, the air may reduce an efficacy of the oil, and result in increased engine wear and engine damage.
One attempt at a dual oil supply pump is disclosed in U.S. Pat. No. 7,290,991 that issued to Staley et al. on Nov. 6, 2007 (“the '991 patent”). In particular, the '991 patent discloses an oil pump assembly having first and second pump mechanisms contained within a common housing. The pump mechanisms may have different displacements or flow rates if desired. As described in the '991 patent, the first and second pump mechanisms draw in oil through an inlet of the housing and discharge the oil toward respective outlets. The '991 patent indicates that as the oil pump outlet pressure increases at the outlets during engine operation, pressure relief valves open at respective pressure control settings. The valves direct excess oil flow to a common reservoir. The '991 patent states that this maintains prescribed oil pressures at the outlets and in connecting galleries of the engine, and limits the likelihood of pump cavitation.
While the dual supply oil pump of the '991 patent attempts to maintain prescribed oil pressures at outlets of the oil pump, the '991 patent does not address compensating for system pressure losses that result from engine wear over time. Particularly, the '991 patent does not address compensating for system pressure losses while maintaining a capacity of the oil pump at less than a capacity of a scavenge pump. As described above, air entrainment in the oil may result when the capacity of the oil pump is near the capacity of the scavenge pump, thereby worsening engine performance, wear, damage, and/or the like.
The oil pump of the present disclosure solves one or more of the problems set forth above and/or other problems in the art.
According to some implementations, an oil pump for an engine may include a first pump mechanism configured to supply oil to a main lubrication gallery of the engine; and a second pump mechanism configured to supply oil to a piston cooling gallery of the engine, the first pump mechanism being designed for a first type of engine and the second pump mechanism being designed for a second type of engine, and the first type of engine having a greater quantity of cylinders than the second type of engine.
According to some implementations, an engine may include a main engine component that is supplied oil by a main lubrication gallery; a piston-cylinder component that is supplied oil by a piston cooling gallery; and an oil pump having: a first pump mechanism configured to supply oil to the main lubrication gallery, and a second pump mechanism configured to supply oil to the piston cooling gallery, the first pump mechanism being designed for another type of engine and the second pump mechanism being designed for the engine, and the other type of engine having a greater quantity of cylinders than the engine.
According to some implementations, a lubrication system for an engine may include a main lubrication gallery configured to supply oil to a main engine component of the engine; a piston cooling gallery configured to supply oil to a piston-cylinder component of the engine; an oil pump having: a first pump mechanism configured to supply oil to the main lubrication gallery, and a second pump mechanism configured to supply oil to the piston cooling gallery, the first pump mechanism being designed for a first type of engine and the second pump mechanism being designed for a second type of engine, and the first type of engine having a greater quantity of cylinders than the second type of engine; and a scavenge pump configured to return spent oil to the oil pump, the scavenge pump being designed for the second type of engine.
This disclosure relates to an oil pump. The oil pump has universal applicability to any machine utilizing an internal combustion engine. The term “machine” may refer to any machine that performs an operation associated with an industry such as, for example, mining, construction, farming, transportation, or any other industry. As some examples, the machine may be a vehicle, a locomotive, a backhoe loader, a cold planer, a wheel loader, a compactor, a generator, a feller buncher, a forest machine, a forwarder, a harvester, an excavator, an industrial loader, a knuckleboom loader, a material handler, a motor grader, a pipelayer, a road reclaimer, a skid steer loader, a skidder, a telehandler, a tractor, a dozer, a tractor scraper, or other above ground equipment, underground equipment, or marine equipment. Moreover, one or more implements may be connected to the machine and driven from the internal combustion engine.
As shown in
The first housing 102 may include a first inlet 108, and the second housing 104 may include a second inlet 110. The first inlet 108 and the second inlet 110 may be supplied oil by a common hose (not shown), such as a manifold, having a first branch that supplies the first inlet 108 and a second branch that supplies the second inlet 110. The first housing 102 may include a first outlet (not shown) opposite the first inlet 108, and the second housing 104 may include a second outlet (not shown) opposite the second inlet 110. Oil (e.g., pressurized oil) may exit the first housing 102 via the first outlet, and oil may exit the second housing 104 via the second outlet. The first outlet and the second outlet may be similarly sized, shaped, and located on the first housing 102 and second housing 104, respectively, as shown in
The oil pump 100 may include an input drive gear 112 that powers the dual pump mechanisms. A power source (not shown), such as the engine, may provide a power input to the input drive gear 112.
As indicated above,
The dual pump mechanisms may include a first pump mechanism 118. The first pump mechanism 118 may be a high-capacity pump mechanism. In such a case, the first pump mechanism 118 may supply oil to a main lubrication gallery, which supplies oil to a main component of the engine (shown in
The dual pump mechanisms may include a second pump mechanism 124. The second pump mechanism 124 may be a low-capacity pump mechanism (i.e., relative to the first pump mechanism 118). In such a case, the second pump mechanism 124 may supply oil to a piston cooling gallery, which supplies oil to a piston-cylinder component of the engine (e.g., engine 142, shown in
The first pump mechanism 118 may be designed for a first type of engine, and the second pump mechanism 124 may be designed for a second type of engine. For example, the first pump mechanism 118 may have a capacity that is designed for (e.g., suitable for) a first type of engine (e.g., prior to use of the first type of engine), and the second pump mechanism may have a capacity that is designed for (e.g., suitable for) a second type of engine (e.g., prior to use of the second type of engine). In other words, the first pump mechanism 118 may have a capacity that is designed to meet oil pressure requirements (e.g., oil pressure requirements for a main engine component) specified for the first type of engine, and the second pump mechanism 124 may have a capacity that is designed to meet oil pressure requirements (e.g., oil pressure requirements for a piston-cylinder component) specified for the second type of engine.
The first type of engine may have a greater quantity of cylinders than the second type of engine, such that the first type of engine has a greater maximum power output than the second type of engine. In such a case, the first type of engine may have greater than 2, 3, 4, 5, 6, 8, 10, 12, 14, 16, 18, 20, or 24 cylinders, and the second type of engine may have 2, 3, 4, 5, 6, 8, 10, 12, 14, 16, 18, 20, or 24 cylinders or fewer, respectively. As an example, the first type of engine may have greater than 16 cylinders, and the second type of engine may have 16 cylinders or fewer. For example, the first type of engine may have 20 cylinders, and the second type of engine may have 16 cylinders.
Accordingly, the first drive gear 120 and the first driven gear 122 may have a greater gear width (e.g., in an axial direction along the drive shaft 114 or the static shaft 116) than the second drive gear 126 and the second driven gear 128. For example, a ratio of a gear width of the first drive gear 120 to the second drive gear 126 may be in a range from approximately 2.75:1 to 3.25:1. As an example, the ratio may be approximately 3:1.
Moreover, the first pump mechanism 118 may have a greater flow rate (e.g., displacement) than the second pump mechanism 124. For example, a flow rate of the first pump mechanism 118 may be in a range from approximately 260 to 300 gallons per minute (GPM), and a flow rate of the second pump mechanism 124 may be in a range from approximately 80 to 120 GPM. As another example, a ratio of a flow rate of the first pump mechanism 118 to a flow rate of the second pump mechanism 124 may be in a range from approximately 2.5:1 to 4:1. As an example, the ratio may be in a range from approximately 2.5:1 to 3:1. A range described herein may include the endpoints specified for the range.
As shown in
In some implementations, the second pump mechanism 124 may be associated with a spacer plate 132. The spacer plate 132 may abut the separation plate 130. The spacer plate 132 may have a particular width that permits reduction in the gear width of the second drive gear 126 and the second driven gear 128 so as to produce a desired flow rate.
As indicated above,
As indicated above,
The engine 142 may be the second type of engine described herein. For example, the engine 142 may have a quantity of cylinders that is less than an engine for which the first pump mechanism 118 is designed. The engine 142 may be an aged engine (e.g., an engine that has experienced wear to parts of the engine, thereby resulting in an oil pressure that is below a threshold value associated with an oil pressure requirement for the engine). For example, the engine 142 may be a rebuilt engine, may have an age, since a first use, that is greater than a threshold age (e.g., 5 years, 10 years, 15 years, and/or the like), may have an associated mileage that is greater than a threshold mileage (e.g., 100,000 miles, 200,000 miles, and/or the like), and/or the like. Parts of the engine 142 (e.g., parts of the main engine component 144) may have greater clearances (e.g., due to wear) than the parts had prior to use of the engine 142. For example, parts of the crankshaft (e.g., the crankshaft and the main bearings) may have greater clearances than the parts of the crankshaft had prior to use of the engine 142.
As further shown in
Spent oil that was supplied to the main engine component 144 and/or the piston-cylinder component 146 may collect in the sump 152. The scavenge pump 154 may return the spent oil from the sump 152 to the oil pump 100. For example, the scavenge pump 154 may return the spent oil from the sump 152 to the oil pump 100 via the filter 156. The filter 156 may be configured to remove particles from the spent oil before the oil is returned to the oil pump 100. In addition, the filter 156 may be associated with an oil cooler and/or a strainer that process the spent oil before the oil is returned to the oil pump 100.
The scavenge pump 154 may be designed for the second type of engine described herein. The scavenge pump 154 may have a greater flow rate than a combined flow rate of the first pump mechanism 118 and the second pump mechanism 124. In particular, the scavenge pump 154 may have a flow rate that is at least 5% greater, at least 7% greater, at least 10% greater, and/or the like, than a combined flow rate of the first pump mechanism 118 and the second pump mechanism 124. For example, the scavenge pump 154 may have a flow rate that is in a range from approximately 425 to 475 GPM. As an example, the scavenge pump 154 may have a flow rate that is approximately 450 GPM.
As indicated above,
The disclosed oil pump 100 may be used with any engine where improved oil pressure is desired, such as an engine that has experienced wear to parts due to use of the engine. In this way, the oil pump 100 may provide oil pressure to an aged engine that is within an optimal range for the engine, thereby reducing engine wear and extending a useful life of the engine. Moreover, the disclosed oil pump 100 provides a retrofit for aged engines that maintains a capacity of the oil pump 100 at less than a capacity of the scavenge pump 154. In this way, the oil pump 100 may be retrofitted to an aged engine without replacement of the scavenge pump 154, thereby improving a useful life of the engine and the scavenge pump 154. For example, the oil pump 100 may be retrofitted to an aged 16-cylinder engine having a scavenge pump 154 that is designed for use with the 16-cylinder engine while maintaining the relative capacities of the oil pump 100 and the scavenge pump 154 within an optimal range, and without requiring replacement of the scavenge pump 154 in order to achieve the optimal range.
As used herein, the articles “a” and “an” are intended to include one or more items, and may be used interchangeably with “one or more.” Also, as used herein, the terms “has,” “have,” “having,” or the like are intended to be open-ended terms. Further, the phrase “based on” is intended to mean “based, at least in part, on.”
The foregoing disclosure provides illustration and description, but is not intended to be exhaustive or to limit the implementations to the precise form disclosed. Modifications and variations may be made in light of the above disclosure or may be acquired from practice of the implementations. It is intended that the specification be considered as an example only, with a true scope of the disclosure being indicated by the following claims and their equivalents. Even though particular combinations of features are recited in the claims and/or disclosed in the specification, these combinations are not intended to limit the disclosure of various implementations. Although each dependent claim listed below may directly depend on only one claim, the disclosure of various implementations includes each dependent claim in combination with every other claim in the claim set.
