FIELD OF INVENTION
This invention relates to Electric Hydraulic system for Compact Electric Tractor used for various applications like, Power Steering and Lift.
The present invention generally relates to an Electric Hydraulic system for Compact Electric Tractor, particularly using a single 8cc pump to deliver the oil to Power steering and Lift both; and wherein said Electric Hydraulic system is so provisioned to provide an integrated system for Power Steering and Hydraulic Lift both for saving the power i.e. the design has switch control to ON/OFF the motor as per the requirement.
BACKGROUND/PRIOR ART
In Modern farming many mechanical operations are getting converted into more reliable electric operation in Tractor system. Tractors are widely used in different agriculture operations. As maximum of agriculture operations are done with the use of hydraulic lift, so hydraulic lift in tractor is a very vital component for agriculture operations.
Usually Tractors have a mechanical gear pump to drive the hydraulic system. These gear pumps are coupled with the Engine crank shaft by means of some spur-gear reduction. Gear pump withdraws the power whenever the Engine is running. Conventional structure, i.e. hydraulic circuit in the regular Compact Electric Tractor, comprises two pumps working in tandem to operate both:-
Power steering as well as Hydraulic Lift. In conventional practice, there are two separate hydraulic pumps for both the operations, one is 6 cc for Power steering operation and another is 8 cc for Hydraulic Lift operation. Both the pumps continuously withdraw the power from engine while it is running. Thus there is always a power loss whether the power steering is getting used and lift operation or not.
OBJECTS OF THE INVENTION
The primary object of the present invention is to provide compact design of Electric Hydraulic system using a single 8cc pump to deliver the oil to Power steering and Lift both.
Another objective of the present invention is to provide an integrated system for Power Steering and Hydraulic Lift both for saving the power i.e. the design has switch control to ON/OFF the motor as per the requirement.
At the outset of the description, which follows, it is to be understood that the ensuing description only illustrates a particular form of this invention. However, such a particular form is only an exemplary embodiment, without intending to imply any limitation on the scope of this invention. Accordingly, the description is to be understood as an exemplary embodiment and teaching of the invention and not intended to be taken restrictively.

BRIEF DESCRIPTION OF THE INVENTION:
According to this Invention, there was a need to design the Hydraulic system for an Electric Vehicle in which the Traction Motor is directly connected with the Transmission. For intended Tractor application, Traction Motor rotates in both directions. Gear pump has the constraint to rotate in only one direction to deliver the oil in hydraulic system to actuate power steering and lift mechanism and also if the Geared-pump rotates in reverse direction it will get damage immediately as soon as it goes under operation.
Present invention comes up with the idea to run the Gear pump via BLDC motor, which is provisioned to function independently with main drive motor. To transfer torque/power smoothly from drive to driven shaft, the coupling of the Geared Hydraulic Pump and BLDC Motor is done through spline.

Brief Description of the Drawings included herein to illustrate the invention:
Figure 1: Schematic depiction of one view (complete) of the BLDC motor, having the internal spline and also one complete view (complete) of the Hydraulic pump with its external spline shaft; wherein said BLDC motor and said Hydraulic Pump are assembled within the Electric Hydraulic System to deliver the oil to Power steering and Lift both;
Figure 2: Represents the schematic view of the special mounting adapter plate of the invention, and also the schematic scheme to be utilized for engaging and assembling said BLDC motor and said Hydraulic Pump together;
Figure 3: It represents one schematic complete view of the BLDC motor, being assembled and used in the Electric Hydraulic System of the instant invention;
Figure 4: It represents one schematic complete view of the Hydraulic Pump, being assembled and used in the Electric Hydraulic System of the instant invention;
Figure 5: It represents schematic view of the flow divider component, being assembled and used in the Electric Hydraulic System of the instant invention;
Figure 6: It represents schematic view of the Power steering component, being assembled and used in the Electric Hydraulic System of the instant invention;
Figure 7: It represents schematic view of the Hydraulic Lift component, being assembled and used in the Electric Hydraulic System of the instant invention;
Figure 8: It represents schematic view of the BLDC Controller component, being assembled and used in the Electric Hydraulic System of the instant invention;
Figure 9: It represents schematic view of the Pump On/Off Switch, being assembled and used in the Electric Hydraulic System of the instant invention;

Figure 10: It represents schematic view of the Hydraulic Lift Selection Switch, being assembled and used in the Electric Hydraulic System of the instant invention;
Figure 11: It represents schematic view of the complete assembly of all major components mentioned herein, in the schematic circuitry of the Electric Hydraulic System of the instant invention;
Figure 12: It represents schematic hydraulic circuit of the Electric Hydraulic System of the instant invention, wherein it is preferably a schematic representation of the embodiment of said circuit of hydraulic circuit, compact electrical-20HP.
Details and Complete flow diagram of the e-Hydraulic System is shown in figures.
Following are the major components used for making the working model of the invention:
Structural component of the instant e-Hydraulic System of the instant invention Numeric reference to indicate the said structural component
BLDC Motor 1
8cc Hydraulic Pump 2
Flow Divider 3
Power Steering 4
Hydraulic Lift 5
BLDC Controller 6
Pump ON/OFF switch 7
Hydraulic Lift Selection Switch 8
Tubing 9
Hydraulic Circuit Diagram 10
special mounting adapter plate 11
Such arrangement of Electric Hydraulic system using a single 8cc pump to deliver the oil to Power steering and Lift both is clearly depicted in enclosed figures, including figure 1.
As per the illustration of Figure 1, Gear Pump has an input shaft with External Spline. The Challenge to design proper spline shaft for coupling Motor with Hydraulic pump has been overcome by the Internal Spline shaft on the Motor which allows the Pump to be directly coupled with the Motor.
For packaging of Hydraulic Pump and BLDC motor on Tractor is incorporated by very Simple way.
As illustrated in the schematic drawing of Figure 2, a special mounting adapter plate has been created for the instant invention.
There is provision for both, Pump and Motor to be held together on adapter plate for mounting the complete system on the Tractor Chassis.
Single Pump is provisioned to operate the Power Steering and Lift functions of the said hydraulic system of the vehicle
As there are mainly two application of the electric hydraulic system in this particular invention, one for power steering and another for operation of Lifting implement, here a flow divider is used to control the flow for both the application as a single pump and motor combination is designed to meet both the requirements.
Basic Working Principle:
As mentioned above single Motor-pump combination is used for meeting hydraulic operations. To meet flow requirements of the steering and lifting, a
Flow divider is used which sets the required value to divide 8cc pump flow into 3cc for Power Steering and 5cc for Hydraulic Lift.
There is also a facility to control the motor-pump RPM based on requirement of flow, through electric on-off switch.
By doing so one can select the two different operating motor speeds. This is to optimize the power consumption and facilitate un-interrupted hydraulic operation.
Detailed description of the invention with the help of drawings:
The present disclosure relates to an Electric Hydraulic system for Compact Electric Tractor, which mainly comprises structural components, namely BLDC Motor (1), Hydraulic Pump (2), Flow Divider (3), Power Steering (4), Hydraulic Lift (5), BLDC Controller (6), Pump ON/OFF switch (7), Hydraulic Lift Selection Switch (8), Tubing (9) and Hydraulic Circuit Diagram (10); wherein Said Electric Hydraulic System is characterized in at least one of the followings:
(i) Said Pump (2) and said motor (1) are held together on an adapter plate (11) for mounting the complete system on the said tractor Chassis;
(ii) Single Pump (2) is provisioned to operate the Power Steering (4) and Lift functions of the said hydraulic system of the said electric tractor; and
(iii) Single flow divider (3) is used to control the flow of oil within the hydraulic circuit towards operating the Power Steering (4) as well as conducting the Lift functions of the said electric tractor.
The preferred embodiment of said Electric Hydraulic system of the invention comprises single 8cc hydraulic pump (1) provisioned to flow 3cc for Power Steering of the vehicle and 5cc for realizing Hydraulic Lift operations thereof.
The adapter plate (11) is provisioned in the said hydraulic system for integrating Motor (1) - pump (2) combination as a single unit for meeting all hydraulic operations of the said electric tractor. Said adapter plate (11) is that novel structural component, which is responsible for mounting of the said electric hydraulic system on the chassis of the tractor.
Said integrated unit Motor (1) - pump (2) combination is further assembled with the Flow divider (3), which is so provisioned to set the required value of oil flow to divide pump (2) flow for operating Power Steering (4) of the said electric tractor and also for realizing Hydraulic Lift thereof.
There is provision of the electric on-off switch (7), which is characterized in controlling and regulating the motor-pump RPM, based on requirement of flow.
Most preferred embodiment of the Electric Hydraulic system of the instant invention comprises a single 8cc pump to deliver the oil to Power steering and Lift both, wherein said embodiment of the Electric Hydraulic system is characterized in at least one of the following advantageous functional and/or structural features:
• Unique solution to meet Electric Tractor requirements;
• Compact design of e-Hydraulic system with high efficiency;
• Only single Pump is used with Flow-divider to operate Power Steering and Lift both;
• Power saving by having ON/OFF mode and Power Steering and Lift selection mode;
• Easy to operate;
• Cost effective Hydraulic Systems for Electric Vehicle;
• Two Pumps are replaced by single pump.
Towards power saving the Electric Hydraulic system of the said electric tractor is provisioned with BLDC Controller (6), Pump ON/OFF switch (7) and Hydraulic Lift Selection Switch (8) to control ON/OFF the motor (1) and regulate the oil flow as per the requirements of power steering and hydraulic Lift thereof.
ADVANTAGEOUS FEATURES OF THE PRESENT INVENTION
1) Unique solution to meet Electric Tractor requirements;
2) Compact design of e-Hydraulic system with high efficiency;
3) Only single Pump is used with Flow-divider to operate Power Steering and Lift both;
4) Power saving by having ON/OFF mode and Power Steering and Lift selection mode;
5) Easy to operate;
6) Cost effective Hydraulic Systems for Electric Vehicle;
7) Two Pumps are replaced by single pump.
It will be apparent to those skilled in the art that various modifications and variations can be made in the dimensional and structural arrangements within the Electric Hydraulic system of the present invention, without departing from the spirit or scope of the invention. Thus, it is intended that the present invention covers the modifications and variations of this invention provided they come within the scope of the description, illustrations, drawings, appended claims and their equivalents.

We Claim:

1. Electric Hydraulic system for Compact Electric Tractor, mainly comprises BLDC Motor (1), single Hydraulic Pump (2), Flow Divider (3), Power Steering (4), Hydraulic Lift (5), BLDC Controller (6), Pump ON/OFF switch (7), Hydraulic Lift Selection Switch (8), Tubing (9) and Hydraulic Circuit Diagram (10).
2. Electric Hydraulic system for Compact Electric Tractor, as claimed in claim 1, wherein said Electric Hydraulic System is characterized in at least one of the followings:
• Said Pump (2) and said motor (1) are held together on an adapter plate (11) for mounting the complete system on the said tractor Chassis;
• Single Pump (2) is provisioned to operate the Power Steering (4) and hydraulic Lift (5); and
• Single flow divider (3) is used to control the flow of oil within the hydraulic circuit towards operating the Power Steering (4) as well as conducting the Lift functions of the said hydraulic Lift (5) in the electric tractor.
2. Electric Hydraulic system, as claimed in claim 1, wherein the preferred embodiment of said system comprises single 8cc hydraulic pump (1) provisioned to flow 3cc for Power Steering of the vehicle and 5cc for realizing Hydraulic Lift (5) operations thereof.
3. Electric Hydraulic system, as claimed in claim 1, wherein said system is characterized in the adapter plate (11) for integrating single Motor (2)-pump (1) combination for meeting all hydraulic operations of the said electric tractor.
4. Electric Hydraulic system, as claimed in claim 1, wherein the Flow divider (3) is so provisioned to set the required value of oil flow to divide pump (1) flow for operating Power Steering (4) of the said electric tractor and also for realizing Hydraulic Lift (5) thereof.
5. Electric Hydraulic system, as claimed in claim 1, wherein the electric on-off switch (7) is characterized in controlling and regulating the motor-pump RPM, based on requirement of flow.
6. Most preferred embodiment of the Electric Hydraulic system, as claimed in claim 1, comprises a single 8cc pump (1) to deliver the oil to Power steering (4) and Hydraulic Lift (5) both, wherein said embodiment of the Electric Hydraulic system is characterized in at least one of the following advantageous functional and/or structural features:
• Unique solution to meet Electric Tractor requirements;
• Compact design of e-Hydraulic system with high efficiency;
• Only single Pump (1) is used with Flow-divider (3) to operate Power Steering (4) and Hydraulic Lift (5) both;
• Power saving by having ON/OFF mode and Power Steering and Lift selection mode;
• Easy to operate;
• Cost effective Hydraulic Systems for Electric Vehicle;
• Conventional practice of two pumps are replaced by single pump in the instant Electric Hydraulic system.
7. Electric Hydraulic system, as claimed in claim 1, wherein towards power saving the said hydraulic system of the electric tractor is provisioned with BLDC Controller (6), Pump ON/OFF switch (7) and Hydraulic Lift Selection Switch (8) to control ON/OFF the motor (2) and regulate the oil flow as per the requirements of power steering and hydraulic Lift thereof.