Automatic additive replenishment system for IC engine lubricating oil

• US 20040079589A1
• Filed: 10/23/2002
• Published: 04/29/2004
• Est. Priority Date: 10/23/2002
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations Incorporated (Motors Liquidation Co. GUC Trust)
• Inventors: Schneider, Eric West
• Granted Patent: US 6,938,585 B2
• Time in Patent Office: Days
• US Class Current: 184/1.5
• CPC Class Codes: F01M 11/0004 Oilsumps
• CPC Class Codes: F01M 9/02 having means for introducing additives to lubricant

Abstract

Method and apparatus for automatically replenishing additives lost from the lubricating oil of an IC engine, by injecting controlled quantities of the additive into the oil. The amount and frequency of injection is controlled by either the operating conditions of the oil (e.g. its thermal history), or changes the properties of the oil (e.g. its electrochemical activity, or dielectric constant).

Claims

1. Method for prolonging the useful life of lubricating oil in an internal combustion engine, said oil when fresh comprising a first concentration of at least one perishable, life-extending additive, comprising storing a replenishable supply of liquid additive-concentrate proximate said engine, said additive-concentrate having a second concentration of said additive greater then said first concentration, operating said engine under a condition that depletes said additive from said oil, and injecting said additive-concentrate into said oil at a rate controlled by said condition so as to replenish additive lost from said oil.

2. A method according to claim 1 wherein is provided by a hydraulic head of said additive-concentrate provides pressure for said injecting.

3. Method according to claim 2 wherein said additive is an anti-oxidant and said condition is an oil temperature greater than 60°

C.

4. Method according to claim 2 wherein said supply of additive-concentrate is stored within said engine.

5. Method according to claim 1 wherein a pump provides pressure for said injecting.

6. Method for prolonging the useful life of lubricating oil in an internal combustion engine, said oil when fresh comprising a first concentration of at least one perishable, life-extending additive, comprising the steps of:

storing a replenishable supply of liquid additive-concentrate proximate said engine, said additive-concentrate having a second concentration of said additive greater then said first concentration;

empirically determining a depletion rate of said additive from said oil under a certain engine-operating condition, operating said engine under said condition;

monitoring said engine-operating condition while operating said engine to determine when a predetermined amount of said additive has been lost from said oil; and

injecting a predetermined quantity of said additive-concentrate into said oil when said monitoring indicates that said predetermined amount has been reached.

7. Method for prolonging the useful life of lubricating oil in an internal combustion engine, said oil when fresh comprising a first concentration of at least one perishable, anti-oxidant, comprising the steps of:

storing a replenishable supply of liquid anti-oxidant-concentrate proximate said engine, said anti-oxidant-concentrate having a second concentration of said anti-oxidant greater then said first concentration;

empirically determining a depletion rate of said anti-oxidant from said oil at various temperatures above 60°

C.;

operating said engine at said temperatures;

monitoring the temperature of said oil while operating said engine to determine when a predetermined amount of anti-oxidant has been lost from said oil; and

injecting a preset quantity of said anti-oxidant into said oil when said monitoring indicates that the additive needs replacing.

8. Method for prolonging the useful life of lubricating oil in an internal combustion engine, said oil when fresh comprising a first concentration of at least one perishable, life-extending additive, comprising the steps of:

storing a replenishable supply of liquid additive-concentrate proximate said engine, said additive-concentrate having a second concentration of said additive greater then said first concentration;

operating said engine under conditions that deplete said additive from said oil;

sensing a physical property of said oil that is indicative of the depletion of said additive in said oil, and injecting a predetermined quantity of said additive-concentrate into said oil when said sensing indicates that said depletion has reached a predetermined amount.

9. Method according to claim 8 wherein said property is the electrochemical activity of said oil.

10. Lubrication system for an internal combustion engine comprising a sump for collecting oil drained from the engine'"'"'s moving parts, said oil, when fresh, comprising a first concentration of at least one perishable, oil-life-extending additive depletable from said oil under a certain engine-operating condition, a plurality of passageways in said engine for delivering said oil to said moving parts, a first pump for pumping said oil from said sump into said passageways to lubricate said moving parts, a reservoir containing an additive-concentrate having a second concentration of said additive greater then said first concentration, a nozzle for injecting said additive-concentrate into said oil, a conduit communicating said reservoir and said nozzle for conducting said additive-concentrate from said reservoir to said nozzle, and a pressurizer for applying sufficient pressure on said additive-concentrate to inject said additive-concentrate into said oil to replenish additive lost from said oil.

11. A lubrication system according to claim 10 wherein said pressurizer comprises a second pump, and said system further comprises a sensor for monitoring said operating condition and reporting said conditions to a controller, and a controller that signals activation of said second pump to pump said additive-concentrate into said oil when said conditions warrant the addition of said additive to said oil.

12. A lubrication system according to claim 10 wherein, said additive-concentrate comprises an anti-oxidant having a predetermined viscosity that decreases as its temperature increases, said pressurizer comprises a hydraulic head of said additive-concentrate in said reservoir, and said nozzle comprises at least one orifice immersed in said oil and sized to inject said additive-concentrate into said oil at increasing rates as said temperature increases from above 60°

C.

13. A lubrication system according to claim 11 wherein said sensor is a temperature sensor for monitoring the temperature of said oil, and said controller tracks the thermal history of said oil and triggers said activation when said thermal history indicates that cumulatively said oil has been used above 60°

C. for longer than a predetermined period of time.

14. A lubrication system according to claim 10 wherein said nozzle comprises a solenoid-operated valve, and said engine includes a sensor for monitoring at least one engine operating condition that causes depletion of said additive from said oil and reporting said condition to a controller, and a controller that signals opening of said valve to inject said additive-concentrate into said oil.

15. A lubrication system according to claim 14 wherein said sensor is a temperature sensor, and said controller tracks the thermal history of said oil and triggers said opening when said thermal history indicates that said oil has been used above 60 ^co for longer than a predetermined period of time.

16. A lubrication system according to claim 10 further comprising an oil degradation sensor for monitoring the degradation of said oil and triggering injection of said additive-concentrate into said oil when said oil has degraded a predetermined amount.

17. An internal combustion engine comprising a crankcase for collecting oil drained from the engine'"'"'s moving parts, said oil when fresh containing a first concentration of at least one perishable, oil-life-extending additive depletable from said oil under a certain engine-operating condition, a plurality of passageways for delivering said oil to said moving parts, a pump for pumping said oil from said crankcase into said passageways under pressure to lubricate said moving parts, a reservoir within said crankcase containing an additive-concentrate having a second concentration of said additive greater then said first concentration, a nozzle beneath said reservoir and immersed in said oil in said crankcase for injecting said additive-concentrate into said oil when the temperature of said oil exceeds 60°

C., a conduit depending from said reservoir and communicating with said nozzle for conducting said additive-concentrate from said reservoir to said nozzle, a hydraulic head of said concentrate in said reservoir for applying pressure on said additive-concentrate behind said nozzle to inject said additive-concentrate into said oil to replenish additive lost from said oil, a filler opening in said reservoir for replenishing said additive-concentrate when depleted from said reservoir, and a liquid level sensor communicating with said reservoir for signaling the operator of the engine when the level of additive-concentrate in said reservoir is low.