Claims:WE CLAIM:
1. A gear arrangement (100) for driving hydraulic pump through top PTO shaft, comprising of:
a transmission case (10);
an input shaft (20) supported by and projecting outwardly from the transmission case (10);
a plurality of gears (30, 40, 50) being positioned within the transmission case (10); said plurality of gears (30, 40, 50) includes a pump drive gear (30) and a pump driven gear (40) which are meshed with a pump cluster gear (50), wherein the pump drive gear (30) is embedded externally with the input shaft (20); and
a hydraulic pump (60) configured to connect with a pump input shaft (70) such that the pump driven gear (40) is embedded with the pump input shaft (70), wherein the hydraulic pump (60) is driven by the input shaft (20) through the pump driven gear (40).

2. The gear arrangement (100) as claimed in claim 1, wherein the input shaft (20) is a 12 + 12 transmission PTO (Power Take-off) shaft which is located on a top portion of the transmission case (10).

3. The gear arrangement (100) as claimed in claim 2, wherein the top PTO shaft is directly connected with an engine such that power is transmitted from the engine to the top PTO shaft.

4. The gear arrangement (100) as claimed in claim 2, wherein the top PTO shaft has a protruding shaft portion protruding into the transmission case (10).

5. The gear arrangement (100) as claimed in claim 1, wherein the hydraulic pump (60) is an axial piston pump.

6. The gear arrangement (100) as claimed in claim 1, wherein the input shaft (20) and the pump input shaft (70) are integrated within the transmission case (10).

7. The gear arrangement (100) as claimed in claim 1, wherein the plurality of gears (30, 40, 50) is spur gears.

8. The gear arrangement (100) as claimed in claim 7, wherein the spur gears are made of steel material.

9. The gear arrangement (100) as claimed in claim 7, wherein the ratio of spur gears is at 1:2.17.

Dated this 12th Day of March 2020

, Description:GEAR ARRANGEMENT FOR DRIVING HYDRAULIC PUMP THROUGH TOP PTO SHAFT
FIELD OF INVENTION
The present invention relates to the field of gear arrangement for use in working vehicles such as agricultural tractors, and more particularly, to the invention relates to gear arrangement for driving a hydraulic pump through a top PTO (Power Take-off) shaft in working vehicles and industrial vehicles. Therefore, the reduction of gear ratio is provided by taking power from the top PTO shaft.
BACKGROUND OF INVENTION
In general, hydrostatic transmissions include a variable displacement hydraulic pump driven by an input shaft. Typically, the hydraulic fluid is pumped from the hydraulic pump to a fixed displacement hydraulic motor for driving an output shaft. In these hydraulic pump devices, there are no mechanical linkage between the input shaft which drives the hydraulic pump and the output shaft which is driven by the hydraulic motor.
In addition to the transmission of working vehicles is the capability of transmitting power for driving working implements. This conventionally is accomplished through the use of power take-off (PTO) shafts which are driven by the transmission and, in turn, supply power to the working implements. In many cases, a power input shaft is coupled directly to a pump input shaft, and the PTO shaft is drivingly engaged either directly or through a mechanical linkage to the pump input shaft. With this type of arrangement the power which can be transmitted to the working implements is limited by the material strength characteristics of the pump shaft. When the amount of power required by the working implement exceeds the load capacity of the pump shaft, if the pump is not replaced with a more heavy duty device, it is impossible to drive the working implement without inducing failure of the transmission. In the existing working vehicle is driven by the PTO shaft such that the location of PTO shaft is in bottom or intermediate position.

Hence, following prior art documents are disclosed to drive the hydraulic pump through top PTO shaft or input shaft in working vehicles.
US patent number 5,542,307 relates to a hydrostatic transmission provided with a housing, an input shaft supported by and projecting from said housing, a joint disposed on a projecting end of said input shaft, a hydraulic pump disposed in the housing driven by the input shaft, a first output shaft supported by and projecting from the housing, a hydraulic motor disposed in the housing, hydraulically connected with the hydraulic pump, an output connected to the hydraulic motor, a gear transmission disposed in the housing for connecting the output of the hydraulic motor and the first output shaft, a second output shaft supported by and projecting from the housing, a joint disposed on the projecting end of the second output shaft, and a clutch disposed in the housing and selectively operable to connect and disconnect the input shaft and the second output shaft.
US patent number 10,407,864 relates to a work implement requirement determination unit that determines a work implement required horsepower on the basis of an operation amount of a work implement operating member and a hydraulic pressure of a hydraulic pump. A transmission requirement determination unit determines a transmission required horsepower on the basis of a vehicle speed and the operation amount of the accelerator operating member. An engine requirement determination unit determines an engine required horsepower on the basis of the work implement required horsepower and the transmission required horsepower. The required throttle determination unit determines a required throttle value based on an engine requirement.
European patent number 1329354 relates to a working vehicle comprising a variable output HST and a planetary gear unit which are connected with an engine, which is supported on a vehicle frame closer to a first side of a fore and aft direction of the vehicle in vibration free manner so as to together constitute a driving-side unit, which is integrally supported on the vehicle frame in vibration free manner. A transmission case of a transmission is fixedly supported on the vehicle frame closer to a second side of the fore and aft direction of the vehicle with a distance from the driving-side unit. An output element of the planetary gear unit is operatively connected with a wheel drive train of the transmission via a shaft coupling extending along the fore and aft direction of the vehicle.
US patent number 4,262,768 relates to a power transmission system for a tractor comprising a hydraulic pump, a hydraulic motor to be driven by the oil forced out from the pump, a PTO transmission mechanism coupled to the shaft of the hydraulic pump and a wheel transmission mechanism coupled to the output shaft of the hydraulic motor. The power from an engine is transmitted to the PTO transmission mechanism by way of the pump shaft before being delivered to the wheel transmission mechanism.
US patent number 4,938,085 relates to a power transmission system in a tractor having a travelling drive sub-system for driving wheels and a PTO drive sub-system for driving working machines. A transmission case is provided with a single input shaft connected to an engine, and the travelling drive sub-system and the PTO drive sub-system are respectively led out from the input shaft separately. The travelling drive sub-system is connected to the input shaft via a main clutch, and is composed of a multi-stage speed-changer having a plurality of speed-changer clutches. The PTO drive sub-system is connected to the input shaft via a PTO clutch that is different from the main clutch, and at the rear portion of the PTO drive sub-system is provided a power transmission switching apparatus which can selectively transmit power to a plurality of PTO shafts.
US patent publication number 20100331131 relates to a hydraulic pump device for a work vehicle having a transmission case that houses a PTO shaft comprises: a hydraulic pump, a pump input shaft of the hydraulic pump that has a projecting shaft portion projecting into the transmission case, a first bevel gear, and a second bevel gear. The first bevel gear is fitted on the PTO shaft and the second bevel gear is connected to the projecting shaft portion. A holder for supporting the PTO shaft is removably attached to the transmission case. The first bevel gear and the second bevel gear are supported to the holder for rotation about respective axes.
Therefore, the above mentioned prior art documents no where disclose in the gear arrangement with drive the hydraulic pump through the top PTO shaft. Hence, there is requirement for unique gear arrangement for driving the hydraulic pump through top PTO shaft in the working vehicle. Therefore, the reduction of gear ratio is provided by taking the power from the top PTO shaft.
The information disclosed in this background of disclosure section is only for enhancement of understanding of the general background of the invention and should not be taken as acknowledgement or any form of suggestion that this information forms the prior art already known to person skilled in the art.
OBJECTIVE OF THE INVENTION
One or more problems of the conventional prior art may be overcome by various embodiment of the present invention.
It is the primary object of the present invention to provide gear arrangement for driving a hydraulic pump through a top PTO shaft.
Another object of the present invention is to provide the reduction of gear ration by taking power from the top PTO shaft.
Yet another object of the present invention is to provide a simple and compact structure.
These and other objects and advantages of the present subject matter will be apparent to a person skilled in the art after consideration of the following detailed description taken into consideration with accompanying drawings in which the preferred embodiment of the present subject matter are illustrated.
SUMMARY OF THE INVENTION
One or more drawbacks of the conventional hydraulic pump driven by PTO shaft and the additional advantages provided though the present invention relates to gear arrangement for driving the hydraulic pump through the top PTO shaft in working vehicle.
In an embodiment of the present subject matter relates to gear arrangement for driving the hydraulic pump through the top PTO shaft in working vehicles such as agricultural tractors. The present invention comprises a transmission case; an input shaft supported by and projecting outwardly from the transmission case; a plurality of gears being positioned within the transmission case; said plurality of gears includes a pump drive gear and a pump driven gear which are meshed with a pump cluster gear, wherein the pump drive gear is embedded externally with the input shaft. Furthermore, the gear arrangement includes a hydraulic pump configured to connect with a pump input shaft such that the pump driven gear is embedded with the pump input shaft, wherein the hydraulic pump is driven by the input shaft through the pump driven gear.
To further understand the characteristics and technical contents of the present subject matter, a description relating thereto will be made with reference to the accompanying drawings. However, the drawings are illustrative only but not used to limit scope of the present subject matter.
BRIEF DESCRIPTION OF DRAWINGS
Figure 1 illustrates schematic view of gear arrangement for driving hydraulic pump through top PTO shaft, in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION WITH REFERENCE TO THE ACCOMPANYING DRAWINGS
The present invention as embodied by a “gear arrangement for driving hydraulic pump through top PTO shaft in working vehicles" 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 is thus directed to gear arrangement for driving the hydraulic pump through the top input shaft in automotive vehicles. According to the present invention having the aforementioned feature, since the top PTO shaft is driven by an engine to the hydraulic pump through a plurality of gears in gear housing.
Referring may be made to Figure 1 illustrating schematic view of gear arrangement for driving hydraulic pump through top PTO shaft, in accordance with an embodiment of the present invention. The present invention comprises a transmission case (10) which is located in the working vehicle body; an input shaft (20) i.e. 12 + 12 transmission PTO (Power Take-off) shaft, supported by and projecting outwardly from the transmission case (10); and a plurality of gears (30, 40, 50) being positioned within the transmission case (10). The plurality of gears (30, 40, 50) includes a pump drive gear (30) and a pump driven gear (40), wherein the pump drive and driven gears (30, 40) are meshed with a pump cluster gear (50). Accordingly, the pump drive gear (30) is embedded externally with the input shaft (20).
In accordance with an embodiment of the present subject matter relates to the gear arrangement (100) that includes the input shat (20), which is located in top portion of the transmission case (10). Generally, the existing working vehicle`s input shat is located in bottom portion of the transmission case. Engine power is engaged and disengaged by a clutch and transmitted to a driving axis of the PTO input shaft such that the PTO shaft is directly connected with the engine. The top PTO shaft has a protruding shaft portion protruding into the transmission case (10).
Furthermore, the gear arrangement (100) includes a hydraulic pump (60) configured to connect with a pump input shaft (70) such that the pump driven gear (40) is embedded with the pump input shaft (70), wherein the hydraulic pump (60) is driven by the input shaft (20) through the pump driven gear (40).
Accordingly, the hydraulic pump (60) projects outwardly from bottom portion of the transmission case (10), and its pump input shaft (70) projects into within the bottom portion of the transmission case (10), wherein the hydraulic pump (60) is an axial piston pump. The plurality of gears (30, 40, 50) are known as spur gear arrangements, wherein the spur gears are made of steel, and the ratio of spur gears is at 1:2.17.
In accordance with advantages of the present subject matter as compared with the prior art or existing technologies. The present is to provide the gear arrangement which allows easy adjustment of the positions of spur gears for proper meshing, and which also facilitates assembly of the first and second bevel gears into the housing. Therefore, the simple gear arrangement is adopted to drive the hydraulic pump without affecting the transmission parts and PTO shaft, and hence the reduction the gear ratio is achieved by taking power from top PTO shaft.
It is to be understood that this invention is not limited to particular methodologies and materials described, as these may vary as per the person skilled in the art. Further, it is to be understood that the present invention is not limited to the methodologies and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, the preferred methods and materials are described, as these may vary within the specification indicated. It is also to be understood that the terminology used in the description is for the purpose of describing the particular embodiments only, and is not intended to limit the scope of the present invention. One skilled in the art will realise the disclosure may be embodied in other specific forms without departing from the disclosure or essential characteristics thereof.