Patent Application
20060104838
The present invention generally relates to the field of oil lubrication devices for compressors, and more particularly to an integrated eccentric flywheel oil slinger suitable for use in oil lubricated air compressors.
Typically, portable pump devices such as compressors, power washers, and the like include a crankcase or housing encompassing pump components. A gear box often encloses an eccentric, coupled to a drive shaft of the engine or motor powering the pump, for reciprocating a piston in a cylinder. Further, in order to dampen or reduce vibrations caused by any imbalance in the pump mechanism (such as vibrations related to the eccentric's motion) a counter weight and a flywheel may be mounted to the drive shaft. The use of the counter weight and flywheel allows pump vibration to be off-set (such as those caused by piston reciprocation), the overall moment of inertia to be increased and the eccentric to be generally counterbalanced. Additionally, an oil slinger may also be coupled to the shaft to disperse oil from a reservoir or oil sump which is formed in the crankcase or the like for reducing friction and cooling the various pump components. Preferably, an oil slinger is configured to minimize atomization of the oil, account for the pump device being disposed in a non-ideal manner (e.g., disposed on a non-level surface), while providing sufficient lubrication and cooling.
Lower cost oil lubricated air compressors, for example, have employed a “splash” lubrication system to distribute oil from the oil sump to the mechanical bearings, seals, valves, pistons and other parts that require lubrication and oil cooling. A small protruding piece of material or “dipstick” is attached to one or more of the moving components such that during each revolution of the crankshaft, the dipstick dips into the oil sump at sufficient velocity to cause oil to splash onto the components requiring lubrication. The size, shape and velocity of the dipstick must be engineered to assure sufficient lubrication and oil cooling for all components while minimizing atomization of the oil in the crankcase so as to reduce oil loss through the crankcase vent. A higher velocity or larger profile dipstick will improve lubrication and oil cooling but will increase oil atomization and oil loss through the crankcase vent. A less aggressive dipstick velocity or profile will reduce lubrication and oil cooling, but also reduce oil loss through the vent. These conflicting phenomena require designers to compromise their design by reducing the positive benefits of lubrication and oil cooling in order to reduce the negative effects of oil loss.
Additional concerns associated with such traditional splash oil lubrication systems are that a number of the air compressors in which such systems are used are portable and are regularly moved by hand from one work site to another. If such portable air compressors are not properly leveled prior to operation, the dipstick splash lubricator may not reach the oil sump causing a lack of needed lubrication and cooling, possibly leading to subsequent component failure.
Consequently, the foregoing combination of components results in complex assembly and multiple part fabrication which may diminish manufacturing efficiency, require a large number of individual components, require a relatively high level of skill to repair, and the like. Therefore, it would be desirable to provide a pump assembly with a simplified pump component configuration including a lubrication system designed to increase the flow rate of lubricating and cooling oil to lubricated components of an air compressor while reducing oil atomization and oil loss through the crankcase vent. Further, it would be desirable to provide such a lubrication system that is capable of functioning properly while the crankcase is tilted, providing an increased tolerance of operation on non-level surfaces.
Accordingly, the present invention is directed to an integrated eccentric flywheel oil slinger for an oil lubricated compressor crankcase. In a first aspect of the present invention, the integrated eccentric flywheel oil slinger includes a generally cylindrical main body being configured to provide oil to various components of the compressor crankcase and reduce vibrations made by such components. In such embodiment, the generally cylindrical main body includes an aperture for receiving a crankshaft. Further, an eccentric extension protrudes from the generally cylindrical main body and is configured to move about the crankshaft. In addition, the generally cylindrical main body is configured to counter balance the eccentric extension protruding from the generally cylindrical main body and when attached to the crankshaft provides the combined functions of the flywheel, the eccentric, the oil disk slinger and a counterweight.
In further aspects of the present invention, the generally cylindrical main body of the integrated eccentric flywheel oil slinger is configured to counter balance the eccentric extension protruding from the generally cylindrical main body by including apertures or recesses within the generally cylindrical main body. For example, a first aperture in the general shape of a first tear drop which extends through the generally cylindrical main body and a second aperture in the general shape of a second tear drop which extends through the generally cylindrical main body are present to counter balance the mass of the eccentric extension protrusion. Further, in an embodiment, the first aperture is positioned on a first side of the eccentric extension and the second aperture is placed on a second side of the eccentric extension, the second side being generally opposite to the first side. Additionally, the leading edge of the first tear drop providing the first aperture may be formed by the apex of the first tear drop and the leading edge of the second tear drop providing the second aperture may be formed by the base of the second tear drop.
In additional aspects of the present invention, the generally cylindrical main body is partially curved so that the body is concave towards the eccentric extension so that the generally cylindrical main body counter balances the eccentric extension. Further, in an embodiment, the width of the generally cylindrical main body is approximately 0.813 (eight hundred and thirteen hundredths) inches to provide oil to the various pump components.
In another aspect of the present invention, an oil lubricated air compressor assembly is provided. In an exemplary embodiment, the oil lubricated air compressor assembly includes an air storage tank for storing air at a first pressure and an air compressor for compressing air from a second pressure to the first pressure for storage in the air storage tank. In the embodiment, the air compressor includes a cylinder, a piston disposed within the cylinder, a crankcase housing a crankshaft assembly for reciprocating the piston within the cylinder, an oil sump formed in the crankcase for containing lubricating oil for lubricating the cylinder and piston, and an integrated eccentric flywheel oil slinger positioned below the cylinder. The integrated eccentric flywheel oil slinger disk shaped oil may include a generally cylindrical main body being configured to function as a oil disk slinger and a flywheel. Moreover, the generally cylindrical main body includes an aperture for coupling with the crankshaft assembly and an eccentric extension protruding from the generally cylindrical main body being configured to move about the crankshaft assembly. Further, a motor is included for driving the crankshaft assembly for reciprocating the piston within the cylinder. Rotation of the crankshaft assembly by the motor rotates the integrated eccentric flywheel oil slinger for splashing lubricating oil from the oil sump onto the cylinder and piston.
In even further aspects of the present invention, the oil lubricated air compressor assembly, includes a generally cylindrical main body which is configured to counter balance the eccentric extension protruding from such body by including apertures or recesses within the generally cylindrical main body. For instance, a first aperture in the general shape of a first tear drop which extends through the generally cylindrical main body and a second aperture in the general shape of a second tear drop which extends through the generally cylindrical main body are present to counter balance the mass of the eccentric extension protrusion. Further, in an embodiment, the first aperture is positioned on a first side of the eccentric extension and the second aperture is placed on a second side of the eccentric extension, the second side being generally opposite to the first side. Additionally, the leading edge of the first tear drop forming the first aperture includes the apex of the first tear drop and the leading edge of the second tear drop forming the second aperture includes the base of the second tear drop.
In additional aspects of the present invention, the oil lubricated air compressor assembly includes a generally cylindrical main body partially curved so that the body is concave towards the eccentric extension so that the generally cylindrical main body counter balances the eccentric extension. Further, in an embodiment, the width of the generally cylindrical main body is approximately 0.813 inches to provide oil to various components of the air compressor assembly. Moreover, in an embodiment, the air compressor is a direct drive air compressor.
The numerous advantages of the present invention may be better understood by those skilled in the art by reference to the accompanying figures in which:
Reference will now be made in detail to the presently preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings.
Referring now to
In the present embodiment, the air compressor includes a cylinder 106, a piston 108 disposed within the cylinder 106, a crankcase 110 housing a crankshaft assembly 112 for reciprocating the piston 108 within the cylinder 106, an oil sump 114 formed in the crankcase 110 for containing lubricating oil 116 for lubricating the cylinder 106 and piston 108, and an integrated eccentric flywheel oil slinger 118 positioned below the cylinder 106. Further, a motor 120 is included for driving the crankshaft assembly 112 for reciprocating the piston 108 within the cylinder 106. Rotation of the crankshaft assembly 112 by the motor 120 rotates the integrated eccentric flywheel oil slinger 118 for splashing lubricating oil 116 from the oil sump 114 onto the cylinder 106 and piston 108. As illustrated in
Referring to
Further, in an exemplary embodiment, an eccentric extension 128 protrudes from the generally cylindrical main body 126 and is configured to move about the crankshaft 122. Those of skill in the art will appreciate that the eccentric extension may be formed as a solid extension or as a lip which forms the peripheral surface of the eccentric for connection to a piston shaft. In addition, the generally cylindrical main body 126 is configured to counter balance the eccentric extension 128 protruding from the generally cylindrical main body 126 and when attached to the crankshaft 122 provides the combined functions of the flywheel, the eccentric, the oil disk slinger and a counterweight. For example, when in operation, the integrated eccentric flywheel oil slinger 100 provides oil to components of the compressor crankcase and reduces vibrations generated by such components.
With continued reference to
Referring now to
It is contemplated that the mass of the eccentric extension 128 may be counter balanced or offset by additional variations in the configuration of the generally cylindrical main body 126 including partially curvation. For example, the generally cylindrical main body 126 may be partially curved towards the eccentric extension 128 (e.g., concave towards the eccentric extension) so as to optimize the effect of the counter weight along the length of the crankshaft 122 (e.g. the apparatus is generally balanced in the direction of the crankshaft), increase lubrication, or the like. In an advantageous embodiment, the main body is configured (e.g. includes apertures, recesses, curvation, and the like) such that the main body portion is sufficient to counter balance the eccentric extension. However, alternative embodiments of the integrated eccentric flywheel oil slinger may include a counterweight extension formed on the generally cylindrical main body generally opposite the eccentric extension.
Referring to
It is contemplated that the edge portion may include various contours such as fins, slots, grooves, or the like, depending on the requirements of the particular application in which the integrated eccentric flywheel oil slinger 118 is employed. Further, the integrated eccentric flywheel oil slinger 118 may be formed of powdered metal including ferrous powder metal which provides a porous surface to which oil may be absorbed allowing an increased amount of oil to be distributed within the crankcase upon the rotation of the slinger 118 compared to that dispersed by conventional dipper type lubrication systems. Alternatively, the portion of the integrated eccentric flywheel oil slinger 118 which contacts the oil 116 present within the oil sump 114 may be coated with powdered metal to impart similar advantageous properties (e.g. oil being absorbed by the slinger resulting in more oil volume to the crankcase upon the rotation of the slinger for more oil is adhering to the slinger). In additional embodiments, the integrated eccentric flywheel oil slinger 118 may be made of cast iron or a combination of powdered metal and cast iron or steel. For example, the inner part of the integrated eccentric flywheel oil slinger 118 may be made of powdered metal while the outer rim may be made of steel.
Referring to
As illustrated in
Since the lower portion of the integrated eccentric flywheel oil slinger 118 remains in the oil 116 instead of cyclically entering and exiting the oil 116, as does a conventional dipstick or dipper oil slinger, the volume of oil 116 in the oil sump 114 that the integrated eccentric flywheel oil slinger 118 displaces does not change during each revolution of the crankshaft assembly 112. Further, the integrated eccentric flywheel oil slinger 118, being a continuous disk, does not have a high speed advancing edge that must pass through the lubricating oil 116 as do dipper slingers. Thus, the flow of lubricating oil 116 over the surface of the integrated eccentric flywheel oil slinger 118 as it advances through the oil sump 114 is substantially more laminar than is possible with intermittent dipper slingers. As a result, the integrated eccentric flywheel oil slinger 118 of the present invention is capable of moving lubricating oil 116 about the crankcase 110 with substantially less atomization of the oil 116.
The amount of oil flow generated by an oil slinger is proportional to the surface area of the submerged portion of the slinger, and proportional to the amount of time that the slinger is submerged during each revolution of the crankshaft. Because the lower portion of the disk oil slinger 118 is continuously submerged in the lubricating oil 116 contained in the oil sump 114, and the submerged surface area of the integrated eccentric flywheel oil slinger 118 is substantially larger than that of the dipper of a dipper oil slinger, the oil flow rate of the integrated eccentric flywheel oil slinger 118 of the present invention is significantly greater than that of an intermittent dipper slinger.
In addition, the volume of oil circulated by the integrated eccentric flywheel oil slinger 118 is significantly increased by increasing the width of the generally cylindrical main body 126. In an embodiment, the width of the generally cylindrical main body is approximately 0.813 inches compared to the traditionally narrow prior art disk slingers generally 0.033 inches in width. The increased width increase the volume of oil circulated by the integrated eccentric flywheel oil slinger 118 which improves the cooling capability of oil flow in the crankcase 110.
In additional embodiments, the air compressor assembly 100 may include a direct drive air compressor. Such assembly may also include a piston 108 with a large diameter (e.g., two inches and seven eighths of an inch) operationally coupled to the integrated eccentric flywheel oil slinger 118 to maximize piston cooling and enable a compressor to operate at higher pressures than compared to a similar direct drive air compressor assembly including a standard/average sized piston (e.g. piston diameter ranging from two inches to two inches and three eighths of an inch). As operating pressure and compression ratio of a compressor increase, compression chamber temperature increases and if not compensated for may lead to a thermal breakdown of the oil residue in the chamber causing unwanted oil residue deposits on compressor valves as well as on a checkvalve in the storage reservoir. Oil cooling of the piston and compression chamber is proportional to the surface area of the piston which is proportional to the piston diameter. Thus, a small piston diameter (e.g., piston diameter ranging from two inches to two inches and three eighths of an inch) reduces the effectiveness of the integrated eccentric flywheel oil slinger. Therefore, the combination of an integrated eccentric flywheel oil slinger 118 with an increased width and a piston 108 with a large diameter (e.g. two inches and seven eighths of an inch) may be used to maximize piston and compression chamber cooling and enable the compressor to operate at higher pressures.
Referring now to
It is contemplated that the instant integrated eccentric flywheel oil slinger may be employed in an air compressor having two or more cylinder/piston assemblies. In an embodiment, the cylinder assemblies are configured such that a single integrated eccentric flywheel oil slinger 118 is sufficient to provide lubrication to both assemblies. For example, cylinder assemblies may be oriented at an angle of approximately ninety degrees to one another and spaced so that they overlap thereby allowing a single plane, generally coaxial with the integrated eccentric flywheel oil slinger 118, to intersect both cylinder assemblies.
Moreover, in other embodiments, air compressors may be provided having multiple cylinder/piston assemblies that are lubricated by two or more integrated eccentric flywheel oil slingers in accordance with the present invention. For example, as illustrated in
It is believed that the present invention and many of its attendant advantages will be understood by the foregoing description, and it will be apparent that various changes may be made in the form, construction and arrangement of the components thereof without departing from the scope and spirit of the invention or without sacrificing all of its material advantages. The form herein before described being merely an explanatory embodiment thereof, it is the intention of the following claims to encompass and include such changes.
The present application claims the benefit under 35 U.S.C. § 119(e) of U.S. Provisional Application Ser. No. 60/567,138, filed Apr. 30, 2004 which is herein incorporated by reference in its entirety. The present application incorporates the following United States Patent Applications by reference in their entireties: U.S. patent application Ser. No. 11/005,887, U.S. patent application Ser. No. 10/118,675, now abandoned, and U.S. patent application Ser. No. 09/861,285.
| Number | Date | Country | |
|---|---|---|---|
| 60567138 | Apr 2004 | US |
