Sump covering filter with bypass valve

Details Sump covering filter with bypass valve Sump covering filter with bypass valve

1999-12-29

2001-09-25

Upton, Christopher (Department: 1724)

Liquid purification or separation

Flow, fluid pressure or material level, responsive

Fluid pressure responsive by-pass

C210S167150, C210S171000, C210S416500, C210S434000, C210S172300

Reexamination Certificate

active

06294083

ABSTRACT:

FIELD OF THE INVENTION
The present invention is directed to sump covering filters which include bypass valves. More particularly, the present invention is directed to a sump covering filter with a bypass valve for filtering liquids such as transmission fluid and lubricating oil.
BACKGROUND OF THE INVENTION
Automatic transmissions experience reduced performance when transmission fluid viscosity is too high due to very cold temperatures because the fluid becomes too viscous or thick to flow readily through the filter media. This results in a reduction in the volume of fluid circulating in the transmission due to increased filter restriction. A reduction in the volume of fluid can starve the pump of transmission fluid so that the shift control valves within the transmission do not operate properly.
In filtering transmission fluid, it is desirable to make the filter media more efficient for removing small particles; however, more efficient filter media tends to increase restriction of fluid flow therethrough which causes flow problems in cold temperature start-ups. Accordingly, there is a need for an arrangement which will allow more efficient filter media for the removal of small particles while not having the drawback of starving transmission pumps of fluid.
Other arrangements may also have these difficulties. For example, lubricating oil used in internal combustion engines may be filtered by filters associated with the lubricating oil pan as opposed to spin-on type filters. At extremely low temperatures, the lubricating oil may so increase in viscosity that it does not pass readily through the filter media and thus the engine associated therewith may be starved of lubricating oil. In addition, lubricating oil filters tend to become clogged and need periodic replacement at intervals usually quite shorter than the intervals for transmission filters. Consequently, if these filters become clogged, there is a need to by-pass the filters as is done with spin-on type oil filters.
While transmissions, such as automatic transmissions and other transmission which utilize oil, and internal combustion engines which utilize lubricating oil, are of primary interest with respect to circulating fluid which has become viscous, there are other types of machinery in which operating or lubricating oil is filtered and in which either cold temperatures or clogged filters result in inefficient or improper operation of the machine. Accordingly, there is a need for arrangements which generally address this problem.
SUMMARY OF THE INVENTION
In view of the aforementioned problems and other problems, it is a feature of the present invention to provide a new and improved arrangement for sump covering filters in which a filter media is by-passed when fluid which normally circulates through the filter media is prevented from doing so efficiently.
In view of this feature and other features, the present invention is directed to an arrangement for filtering a circulating fluid wherein the fluid has a viscosity which varies with temperature and wherein the fluid accumulates in and is pumped from a sump pan. The sump pan has side walls in the bottom wall which are divided by a partition into an upper chamber and lower chamber. The partition has an opening therethrough in which a filter media is positioned so as to filter fluid flowing from the upper chamber through the opening into the lower chamber. A suction tube has a first open end within the lower chamber and a second end which is adapted for connection to a suction pump. A bypass valve is disposed between the upper chamber of the sump pan and the pump to which the suction tube is adapted to connect. The bypass valve opens to allow the fluid to bypass the filter when the viscosity of the fluid is elevated.
In a more specific aspect of the invention, the bypass valve is disposed in the partition.
In still a more specific aspect of the invention, the suction tube as well as the bypass valve are disposed in the partition and the partition is separable from the pan to facilitate assembly and maintenance of the arrangement.
In accordance with one aspect of the invention, the arrangement is used for filtering transmission fluid, and in accordance with another embodiment, the arrangement is utilized to filter lubricating oil.


REFERENCES:
patent: 1230470 (1917-06-01), Farmer
patent: 2192438 (1940-03-01), Gulick
patent: 4261838 (1981-04-01), Halleron
patent: 4352737 (1982-10-01), Taniguchi
patent: 4898207 (1990-02-01), Ueki et al.
patent: 4915852 (1990-04-01), Tomlinson
patent: 5130014 (1992-07-01), Volz
patent: 5339776 (1994-08-01), Regueiro
patent: 5589059 (1996-12-01), Semar
patent: 5863424 (1999-01-01), Lee
patent: 6013179 (2000-01-01), Laughlin et al.

Affiliated with

Also associated with

Rating

Sump covering filter with bypass valve does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Sump covering filter with bypass valve, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Sump covering filter with bypass valve will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2450886