Claims:We claim:
1. A combined forced and immersed lubrication system for a transmission assembly comprising of:
a. a first pump (102), to pump the lubrication oil stored in the oil source to the pressure relief valve (103);
b. a pressure relief valve (103), to redirect the lubrication oil to the transmission case (101);
c. a first compartment (105) comprising of an inlet port (104), a plurality of lubrication tubes, a plurality of first gears (109), a plurality of first bearings (107) and at least a clutch pack (108);
d. a second compartment (106) comprising of a plurality of second gears (111), a plurality of second bearings (112), at least a power take-off clutch (114), a rear axle (115), at least a hydraulic pump (113) and an outlet port (116); and
e. a second pump (110), to transfer the collected lubrication oil from the first compartment (105) to the second compartment (106) by means of a delivery pipe.

2. The combined forced and immersed lubrication system as claimed in claim 1, Wherein the said the plurality of lubricating tubes connected to the inlet port (104) in the first compartment (105) is supplied with lubrication oil to enable forced lubrication of a plurality of first bearings (107), a plurality of first gears (109) and the clutch pack (108) located in the first compartment (105).

3. The combined forced and immersed lubrication system as claimed in claim 1, Wherein the said second pump (110) delivers the lubrication oil to the second compartment (106) to provide immersed lubrication to a plurality of second gears (111), a plurality of second bearings (112), power take-off clutch (114) and a rear axle (115) located in the second compartment (106).

4. The combined forced and immersed lubrication system as claimed in claim 1, Wherein the said first compartment (105) and second compartment (106) is placed inside the transmission case (101).

5. The combined forced and immersed lubrication system as claimed in claim 1, Wherein the said hydraulic pump (113) uses the oil in the second compartment (106) for external application through the outlet port (116).

6. The combined forced and immersed lubrication system as claimed in claim 1, wherein the said pressure relief valve (103) redirects the lubrication oil to the inlet port (104) at a pre-set pressure value, excessive pressure of the lubrication oil is relieved by directing the lubrication oil to the second compartment (106) through an auxiliary passage.

7. The combined forced and immersed lubrication system as claimed in claim 1, wherein the said clutch pack (108) is a double wet clutch.

8. The combined forced and immersed lubrication system as claimed in claim 1, wherein the said clutch pack (108) is a wet clutch.

9. The combined forced and immersed lubrication system as claimed in claim 1, wherein the lubrication oil level in the second compartment (106) is maintained below the clutch pack (108), to eliminate the clutch drag.
, Description:COMBINED FORCED AND IMMERSED LUBRICATION SYSTEM
FOR A TRANSMISSION ASSEMBLY

FILED OF THE INVENTION
The present invention relates generally to lubrication system, more particularly to combined forced and immersed lubrication system for a transmission assembly.
BACKGROUND OF THE INVENTION
Drive power transmission device is a forward/reverse switching device that selectively engages/disengages a frictional engagement element such as a clutch. In agricultural vehicles such as tractor the forward / reverse shuttle is generally provided with a hydraulic clutch which is in line with a main drive shaft. The hydraulic clutch is frequently engaged or disengaged based on the need of the vehicle. Generally, these type of clutches are housed in an housing along with the main drive shaft and shuttle drive shaft, therefore it becomes crucial to maintain the hydraulic oil level in such a clutch assembly housing. Lubrication oil well below a predetermined level causes frictional damages to the moving parts due to lack of lubrication. Hence requires continuous lubrication oil flow to reduce the clutch temperature during operation. Conventionally in tractors immersed lubrication is the common type of lubrication and power shuttle transmission which when immersed in oil generates a drag force between the clutch friction plates. Due to this phenomena, the power shuttle tractor moves in both forward and reverse direction even in the neutral gear mode. In case of tractor gearbox lubrication is either of immersed lubrication type or fully forced lubrication type. In conventional forward/reverse switching device, individual pathways of lubricating oil exist for cooling each frictional engagement element which requires a provision of temperature sensor for each lubricating oil pathway for detecting the temperature of each frictional engagement element this increases the manufacturing cost.
The present invention provides a solution to the existing problems such as clutch drag, continuous flow of lubrication oil and optimum cooling of clutch assembly by providing a combined forced and immersion lubrication system for the power drive transmission assembly. The present invention provides a novel type of lubrication system in the hydraulic circuit and thus maintaining the hydraulic oil level well below the clutch packs in the power shuttle wet clutch unit. Further the present invention is simple in construction and retains the transmission characteristics of the heritage gear assembly for better versatility.
BRIEF DESCRIPTION OF PRIOR-ART
Chinese publication no. 102601140 discloses a forced lubricating device which comprises a lubricating box body and a forced tube the middle of which is communicated, wherein the lubricating box body is arranged at the front end of the forced tube; the forced tube comprises a cone-shaped inlet, a work zone, a high pressure zone, an air vent and a combination position; the cone-shaped inlet is formed at the front end of the work zone; the high pressure zone is arranged at the rear end of the work zone; the air vent is communicated with the high pressure zone; and the combination position is arranged at the rear end of the high pressure zone. According to the forced lubricating device disclosed by the invention, high temperature generated by a wire drawing mould in the wire drawing process is utilized and transferred to the forced tube, and the narrow space of the forced tube is combined, thus wire drawing powder is molten to form a semi-solid state so that the wire drawing powder is completely adhered to the surface of a steel wire; the tube body of the forced tube is a bell-mouthed, so that more wire drawing powder can be conveniently delivered into a wire drawing mould so as to increase the high pressure zone; and the wire drawing powder is easily adsorbed to the surface of the wire and is not reversely refluxed, thereby ensuring the quality of the drawn product.
In the patent document EP0187783, an immersion lubrication system for gear-boxes of motor vehicles is disclosed. The immersion lubrication system comprises an oil pan on the lower side of a case. In the case there is a drive shaft with toothed wheels which are partially immersed in the oil when the oil pan is completely filled. During extremely low operation temperatures, and in order to prevent synchronization devices from sticking to the cold and therefore very viscous oil, which would result in the non-synchronization of the gear shifts and therefore in damages to the gear-box, the oil pan is connected to a hollow chamber wherein the oil is sucked from the oil pan in the case of low operation temperatures of the gear-box. To this effect there is preferably arranged into a hollow space of a drive shaft an extension body which is retracted in the case of a low temperature, the hollow space being connected to the oil pan.

US5400889A discloses a hydraulic clutch assembly enclosed within a housing with automatic oil level control system. The hydraulic clutch, when engaged, connects a front wheel drive shaft to a main vehicle drive shaft. The hydraulic clutch has a tendency to leak fluid into the housing, the fluid level within the housing is controlled by pressurizing the housing via compressed air from a turbocharger or the like. A pair of blow back are positioned such that excess oil is detected and evacuated when the clutch and drive shaft are static or dynamically rotating.

US5845546 (A) provides a twin clutch axle for a motor vehicle with independent fluid filled chambers: a pair of spaced apart chambers each receiving a respective one of the clutches and a separate, intermediate chamber receiving a hypoid drive gear. Each of the clutches is preferably an electromagnetically operated multiple friction plate assembly and the fluid in the clutch chambers is like or similar to automatic transmission fluid. The separate hypoid drive gear chamber is filled with a gear lubricant or heavy weight oil. The pair of clutch chambers may be sealed and fully independent of one another or may be in fluid communication with one another through, for example, passageways or a common sump. By utilizing separate compartments for the clutches and hypoid drive gear, the lubricants utilized therein can be optimized for friction clutch and gear operation thereby improving the performance and service life of the axle.

From the above cited prior art documents it is evident that forced and immersion type of lubrication are commonly used in the drive transmission assembly for the lubrication of clutch assembly and drive gear unit individually. But the need exists for a combined forced and immersed lubrication system, which uses oil from the immersed lubrication (second) compartment and performs forced lubrication in the first compartment. The present invention provides a combined forced and immersion lubrication system for the drive transmission assembly of heritage vehicles.
OBJECTIVES OF THE INVENTION
The primary objective of the present invention is to provide a combined forced and immersed lubrication system for a drive transmission assembly.
Another object of the present invention is to maintain the lubrication oil level in the power shuttle wet clutch compartment to eliminate clutch drag.
yet another object of the present invention is to provide a continuous lubrication oil flow in the power shuttle transmission to reduce the clutch temperature during operation.
still another object of the present invention is to provide a combined forced and immersed lubrication system for a drive transmission assembly which is simple in construction and can be installed without changing the transmission assembly.
SUMMARY OF THE INVENTION
The present invention provides a combined forced and immersed lubrication system for a transmission assembly comprising of : a first pump (102); a pressure relief valve(103); a first compartment (105); a second compartment (106); and a second pump (110). wherein lubrication oil stored in the oil source is pumped to the pressure relief valve (103) by the first pump (102). The lubrication oil pumped to the pressure relief valve (103) is redirected to a transmission case (101). Wherein the said first compartment (105) and second compartment (106) combines to form the said transmission case (101). The said first compartment (105) comprising of a plurality of first gears (109), a plurality of first bearings (107) and at least a clutch pack (108) is force lubricated by means of a plurality of lubrication tubes connected to the inlet port (104) that is supplied with the forced lubrication oil by means of a pressure relief valve(103). The said second pump (110) transfers the collected lubrication oil from the first compartment (105) to the second compartment (106) through a delivery pipe. Wherein the said second compartment (106) comprising of a plurality of second gears (111), a plurality of second bearings (112), an power take-off clutch (114), a rear axle (115), is subjected to immersion type of lubrication by the lubrication oil collected and transferred from the first compartment (105) by means of a second pump (110). The hydraulic pump (113) located in the second compartment (106) uses the oil in the second compartment (106) for external application through the outlet port (116). This eliminates the clutch drag in the wet clutch compartment. The combined forced and immersion lubrication system of the present invention provides a continuous lubrication oil flow in the power shuttle transmission which reduces the clutch temperature during operation. Further the present invention is simple in construction and retains the transmission characteristics of the heritage gear assembly for better versatility.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 depicts a combined forced and immersed lubrication system for a transmission assembly.
While the invention is amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit the invention to the particular embodiments described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.
DETAILED DESCRIPTION OF THE DRAWINGS
The present invention as embodied by a combined forced and immersed lubrication system for a transmission assembly, succinctly fulfils the above-mentioned need(s) in the art. The present invention has objective(s) arising as a result of the above-mentioned need(s), said objective(s) being enumerated below. In as much as the objective(s) of the present invention are enumerated, it will be obvious to a person skilled in the art that, the enumerated objective(s) are not exhaustive of the present invention in its entirety, and are enclosed solely for the purpose of illustration. Further, the present invention encloses within its scope and purview, any structural alternative(s) and/or any functional equivalent(s) even though, such structural alternative(s) and/or any functional equivalent(s) are not mentioned explicitly herein or elsewhere, in the present disclosure. The present invention therefore encompasses also, any improvisation(s)/modification(s) applied to the structural alternative(s)/functional alternative(s) within its scope and purview. The present invention may be embodied in other specific form(s) without departing from the spirit or essential attributes thereof.
Throughout this specification, the use of the word "comprise" and variations such as "comprises" and "comprising" may imply the inclusion of an element or elements not specifically recited.
The present invention provides a combined forced and immersed lubrication system for a transmission assembly comprising of: a first pump (102); a pressure relief valve (103); a first compartment (105); a second compartment (106); and a second pump (110). Wherein, the said first pump (102) pumps the lubrication oil stored in the oil source to the pressure relief valve (103). The pumped lubrication oil is redirected to the transmission case (101) by the pressure relief valve (103). Wherein the said first compartment (105) and second compartment (106) combines to form the said transmission case. The second pump (110) transfers the collected lubrication oil from the first compartment (105) to the second compartment (106) by means of a delivery pipe.
In the preferred embodiment, the said first compartment (105) comprises of an inlet port (104) located at the outer surface, a plurality of lubrication tubes positioned at the inner surface of said first compartment (105), a plurality of first gears (109), a plurality of first bearings (107) and at least a clutch pack (108). The lubrication oil is forced into the inlet port (104) by the pressure relief valve (103), wherein forced lubrication oil entering the first compartment (105) through the inlet port (104) is diverted into various lubrication points by the plurality of lubrication tubes. The said lubricating tubes supplied with lubrication oil provides forced lubrication to a plurality of first bearings (107), a plurality of first gears (109) and the clutch pack (108) located in the first compartment. After forced lubrication, the lubrication oil is collected from the first compartment (105) by the second pump (110) and transferred to the second compartment (106) through a delivery pipe.
In the preferred embodiment, the said second compartment (106) comprises of a plurality of second gears (111), a plurality of second bearings (112), an power take-off clutch (114), a rear axle (115), a hydraulic pump (113) and an outlet port (116) located at the outer surface. The said second pump (110) collects the lubrication oil from the first compartment (105) and delivers it to the second compartment (106) to provide immersed lubrication to a plurality of second gears (111), a plurality of second bearings (112), power take-off clutch (114) and a rear axle located in the second compartment (106). The said hydraulic pump (113) uses the oil in the second compartment (106) and for external application through (106) the outlet port (116). The lubrication oil from the outlet port (116) is transported to the pressure relief valve (103) by the first pump (102).
In the preferred embodiment, Wherein the said pressure relief valve (103) redirects the lubrication oil to the inlet port (104) at a pre-set pressure value, excessive pressure of the lubrication oil is relieved by directing the lubrication oil to the second compartment (106) through an auxiliary passage.
In the preferred embodiment, the lubrication oil level in the second compartment (106) is maintained below the clutch pack (108) to eliminate the clutch drag due to lubrication oil. In
In the preferred embodiment, wherein the said clutch pack (108) is double wet clutch.
In an another embodiment, the clutch pack (108) is wet clutch.
The present invention provides optimum cooling to the clutch assembly by providing a combined forced and immersion lubrication system for the power drive transmission assembly. Continuous flow of lubrication oil to the power shuttle transmission reduces the clutch temperature during operation. Further the combined forced and immersion lubrication system of the present invention is simple in construction and retains the transmission characteristics of the heritage gear assembly for better versatility.
It will be apparent to a person skilled in the art that the above description is for illustrative purposes only and should not be considered as limiting. Various modifications, additions, alterations, and improvements without deviating from the spirit and the scope of the invention may be made by a person skilled in the art.

LIST OF REFERENCE NUMERALS
101. - Transmission case
102. - First pump
103. - Pressure relief valve
104. - Inlet port
105. - First compartment
106. - Second compartment
107. - First bearings
108. - Clutch pack
109. - First gears
110. - Second pump
111. - Second gears
112. - Second bearings
113. - Hydraulic pump
114. - Power take-off clutch
115. - Rear axle
116. - Outlet port