Patent Application
20050126965
This invention relates to the field of oil filters and automotive technology.
The typical engine oil filter system is a single pass, full flow filter that cleans the oil as it flows from the engine oil pump and then directs the flow to the oil galleys and other lubricated components of the engine. In order to more completely cleanse the oil, and to enable longer service life of the oil and engine components, additional, supplemental filtration in the form of by pass filtration is often utilized.
By pass filtration is achieved by diverting a small portion of an engines oil flow from a source under pressure, directing the flow slowly through a dense filter media and returning the bypass-filtered oil to the engine sump. In most applications of full flow and bypass technology, each of these filters are separate units with the full flow filter mounted directly to the engine and the by pass unit mounted remotely, connected to the engine oil system via hoses or other plumbing.
Presently, there are several prior art designs for combining the full flow filter with a by pass filter all in the same housing.
In order to utilize these various combined full flow/by pass filter units one of two conditions must be met:
A further problem, especially with the first filters mentioned above, is that the rate of oil flow through the by pass portion of the combined full flow/by pass filter system must be taken as an article of faith. The separate, independent, and measurable flow of oil through the by pass portion cannot be observed or positively verified.
It is an object of this invention to provide a combination full flow/by pass engine oil filtration system that is easily adaptable to virtually all present day internal combustion engines, requiring no modification to said engine.
It is a further object of this invention to provide a means to readily measure and verify the separate oil flow through the by pass portion of the claimed filtration system.
This invention is designed to provide a high-quality, dependable, combination full flow and bypass filter for lubrication fluids used in modern internal combustion engines.
This invention combines two coaxial cylindrical oil filters with a novel recovery system for returning the oil from the bypass filter to the engine sump, or other relatively low-pressure destination. The bypass filter removes essentially all solid contaminants from a fraction of the engine oil that enters the subject filter, and this clean fraction is returned to the engine oil supply, resulting in a steadily increasing level of oil cleanliness until a steady-state of cleanliness is reached.
The present invention uses a non-venturi method of moving a fraction of the oil from the full flow through the bypass filer, unlike the previous state of the art filters. There are two embodiments of the present invention presented, a completely disposable system and a replaceable system.
The replaceable system possesses a metal full-pass filter screen and a replaceable bypass filter element made of fiber, which can be removed from the filter canister and replaced with a new bypass filter element.
It is an object of this invention that the full flow and bypass filter canister system be compatible with existing engine mounts and require no special equipment be mounted on the engine.
It is an object of this invention that it work with any engine using any standard oil pump and that it not need modifications to a pressure regulator or a pressure relief valve to operate with standard engine oil pressures.
It is an object of this invention that positive fluid flow through both filters can be demonstrated at any engine speed, which competing designs have failed to do.
The construction and operation of the invention can be readily appreciated from inspection of the drawings that accompany this application, combined with the detailed specification to follow.
Referring to
The operation of the filter is that fluid enters the canister 101 through perforations 109 in the tap plate 106 and flows down the outer circumferential area 119 of the canister, entering the full flow filter 103 circumferentially at the outside surface 110 of the full flow filter 103 and proceeding towards the axis of the filter under pressure. The fluid then enters the transition space 111 between the filters and most of that fluid exits the filter canister 101 and directly enters the engine through the discharge opening 112 of the tap plate 106. A fraction of the oil in the transition space 111 enters the bypass filter 102 and exits the bypass filter 102 into the bypass collection space 113, whereupon it exits the filter canister through the bypass flow control orifice 115 and discharge port 114.
The bypass discharge port 114 is connected via hose (not shown) to some low pressure point within the engine where oil can be returned to the engine oil sump. The differential in pressure between the fluid entering the canister 101 and the pressure at the destination of the hose from the bypass return port 114 draws a measurable fraction of the total system oil flow through the denser bypass filter 102. Eventually, all of the fluid passes through the bypass filter 102 and is cleaned to the dimensions allowed by the bypass filter 102. It is a feature of this invention that the fluid is not blended when it leaves the canister, but the bypass filter 102 output is separately directed to the oil sump or other destination.
The bypass filter 102 is comprised from a list of materials such as wound cotton and other dense fibers. The full flow filter 103 is comprised of a material selected from a list including pleated paper and metal mesh.
An alternate embodiment of the present invention in
The fluid flow path is similar to the preferred embodiment. Fluid enters from the engine directly into the chamber 140 and then passes through several flow passages 141 arrayed circumferentially around the full flow discharge opening 142 at the base of the canister body 124, flows down the canister sides 144 and traverses the filter screen 121 to the transition space 129, where under differential engine pressure, a fraction of the fluid enters the bypass filter 120 and makes it through to the interior of the filter 131, where it exits through the bypass return orifice 132.
The gasket 143 for the replaceable embodiment seals the combined full flow/bypass filtration system to the engine filter mount (not shown). Gaskets 146, 147 prevent the oil from taking a short-cut from the chamber 140 to the transition space 129 or from the canister sides 144 to the transition space 129.
The four-bladed anti-blockage cap 150 on top of the bypass filter 120 prevents the bypass filter 120 from blocking oil flow through the rest of the filter, through the filter screen 121, in the event the bypass filter 120 breaks free of its mount 152 inside the filter canister. If that should happen, without the four-bladed anti-blockage cap 150 present, the bypass filter 120 could plug the full flow discharge opening 142, starving the engine for oil and causing catastrophic engine failure.
The dimensions of the disposable filter's bypass return orifice 115 and its equivalent on the replaceable embodiment are important to the effectiveness of the bypass filter 102, 120, and the inventors have discovered that a dimension of 1 millimeter is optimal for this outlet from the bypass filters 102, 120.
It is a feature of this invention that this full flow and bypass filter canister system is compatible with existing engine mounts and requires no special equipment be mounted on the engine.
It is also a feature of this invention that positive fluid flow can be demonstrated through both filters of the system at any engine speed, which competing designs have failed to do. In
While the preferred embodiment and a first alternate embodiment of the invention have been described, modifications can be made and other embodiments of this invention realized without departing from the intent and scope of any claims associated with this invention.
