This invention relates to an optimized integrated hydraulically driven distributor and lifting mechanism for positioning a plurality of mounted apparatus for agricultural applications under a plurality of soil conditions with optimal effort.
DESCRIPTION OF PRIOR ART
A Three Point Linkage lifter with an integrated distributor is known to the art. This comprises a compact distributor that fits into the casing of a lifter and the integrated contraption permits regulation of effort and position of an agricultural tool/ apparatus that is connected via the three point linkage.
In conventional distributor and lifting mechanisms known to the art it is difficult to operate the application under a plurality of target soil conditions over extended continuous usage. A particular known mechanism uses hydraulic input to regulate and modulate output pressure to drive an actuator system to achieve a plurality of apparatus position/ effort based on a plurality of input positions with controlled effort. The flow of hydraulic medium in the distributor by way of alternative options of position either actuates a plurality of such movement by way of modulated force or is released back into the input system. The deficiency in the art relates to the incapacity of the preferred embodiment of the mechanism to address a plurality of target conditions like
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hardness of soil, softness of soil, extended operation of the device at constant efficiency and resultant inherent technical inefficiency.
SUMMARY OF THE PRESENT INVENTION
The present invention cures the inherent incapacity in the prior art as relates to the inefficiencies present in the art. While the invention retains the capabilities of the prior art, it cures the inherent inefficiencies and constraints both in relation to effort parameters (leading to commercial efficiency) as well as the dynamic ability to address various target and soil conditions. The present invention reinvents the art to address the inherent inefficiencies by optimization of the internal parts of the distributor and the actuator mechanisms, resizing of the relative parts and their placement, introduction of additional parts into the sub systems of the prior art, altering the design of the cams, both external and internal, reinventing the roller configuration, resizing the pressure mountings, addition of certain support inserts, redesigning the flange, resulting in reduced negative stroke, lesser hitch regulation percentage, extended force range to hitch regulation percentage sensitivity, improved flow rate capability, leading to higher and continued range of application of the actuator and driven apparatus as well as the ability of the invented product to operate the application under a plurality of target conditions over extended uninterrupted usage at continued efficiency parameters
BRIEF DESCRIPTION OF THE DRAWINGS
Figure A sets out the schematic diagram of the hydraulic distributor that is an integral part of the present invention. A plurality of discharge ducts, intercommunicating with delivery ducts and differential and/ or check valves, either (a) actuate a lifting chamber by means of buildup of pressure of hydraulic medium, or (b) retain the position of the lifting chamber by locking the hydraulic pressure and discharge of the incoming hydraulic medium into a discharge vessel through a plurality of intercommunicating valves and ducts, or (c) releases the lifting chamber to its normal resting position by way of release of pressure of hydraulic medium inside the lifting chamber.

Figure B sets out the reinvented lifter. A control shaft can maneuver the resultant'position of the three point linkage into either of lifting, static or downward movement. The Lifter and Distributor when integrated are referred in the art as Rockshaft. The Rockshaft in its position control embodiment is depicted in Figure B, while in its effort control embodiment is depicted in Figure C.
Figure D illustrates the modifications done in the circled areas of the invention over prior art, Figure E depicts the enhancements done to the pressure loading conditions, Figure F represents the incremental optimization done to the internal and external cams as regards curvature, Figure G represents the modified rolling facilitation arrangement, Figure H represents the flange modifications, Figure I shows the improved Hitch percentage to Force capability over an extended force range.
DESCRIPTION OF THE PREFERRED EMBODIMENT
There are various lifter mechanisms known to the art that combine in an integrated manner a hydraulic distributor with a lifting mechanism to address the issue pf control of movement and effort for positioning a plurality of mounted apparatus for agricultural applications. In this version of the preferred embodiment the hydraulic medium is drawn from the main agricultural machine into at least one inlet of the distributor, from where the pressurized hydraulic medium is either routed through a series of valves, acting in tandem, to a lifting cylinder that powers a plunger that moves a plurality of lifting arms of the lifter, or the hydraulic medium is routed, through a plurality of valves acting in tandem, into a plurality of discharge valves, into the source w of the hydraulic medium. The Lifter is based on linkages so arranged that either effort control, position control or a combination of effort control and position control can be achieved through a mechanized closed loop feedback system. The deficiency present in the art related to movement control capability, effort optimization and ability to address plurality of target conditions leading to dynamically varying drags on the apparatus under management, is eliminated in this preferred embodiment of the present invention.

The Distributor is designed to operate in a plurality of phases: Position stage, Lifting stage, Retraction stage. In the Position stage the Distributor valves act in tandem such that the hydraulic medium stays under pressure without further filling the lifting chamber and thereby exerting reverse pressure on the plunger attached to the lifting arms, not allowing the target implement to move downwards; Non return check valves prevent the pressurized hydraulic medium to get connected to the discharge ducts in order that the pressure built up in the lifting chamber is maintained. In the Lifting stage the pressurized hydraulic medium builds increasing pressure into the lifting chamber and flows into it, thereby causing the plunger inside the lifting chamber to rise, causing an upward movement to the lifting arms. The implement attached to the lifting arms then gets lifted to a position controlled by the position control lever. In the retraction stage, the input control lever is so positioned that the plurality of valves so act in tandem connecting the pressurized hydraulic medium to flow through the discharge valves into the discharge duct/s back into the source of the medium. As a result the pressure of the hydraulic medium inside the lifting chamber gets diffused causing a reverse movement of the lifting plunger inside the lifting chamber, causing the lifting arms and therefore the attached implement, to move downward with a force and speed dictated by the inherent functionality of the preferred embodiment of the present invention.
The Lifter part of the preferred embodiment of the present invention consists of a plurality of levers, cams, rollers, Rocker, springs, and the like so placed and aligned that the lifter, acting in tandem with the Distributor, performs the functionality of position control, effort control or a combination thereof. The control levers are so arranged as to be convenient for the operator to maneuver the device easily and conveniently.
Figure B is a detailed longitudinal section of the Lifter in Position Control functionality
Figure C is a detailed longitudinal section of the Lifter in Effort Control functionality
The shortcomings in an embodiment of a known type of Distributor and Lifter relate to the inability of the device in that embodiment to be able to efficiently address a plurality of target
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conditions like softness of soil, hardness of soil, rocky state of soil etc. leading to a situation where the device is incapable of being efficiently and optimally utilized continuously and uninterruptedly without loss of efficiency. The present invention addresses these shortcomings in the preferred embodiment, by way of an inventive step over the art by optimization of the internal elements and their interplay in order to achieve better hitch regulation, improved draft range, reduced negative stroke, wider force range covered over lower and improved range of hitch regulation percentage, improved closed loop feedback sensor and actuator based automated descent speed. In consequence of these inventive claims, the efficiency of the present invention over the art improves substantially and measurably as shown in the claims. The present invention in its preferred embodiment is capable of addressing a plurality of target soil conditions, run efficiently over extended period of time over the art.
Reference Figure B. A closed loop feedback system comprises of the third arm of the three point linkage acting as a transmitter for the sensor. The vector force on the agricultural apparatus while in operation, due to the compactness or looseness of the target soil being worked upon, gives a feedback to the effort cam (b) via the tie rod (a). The curved face of the effort cam triggers the roller (c) which is linked to a system of levers and shock absorber, moving the position of the control plunger (d) to the neutral hold position. The apparatus, therefore, does not move further downward in spite of the downward pulling force on account of the target soil density. As the downward pulling force increases beyond a certain limit, the effort cam, via the tie rod, moves the roller further on account of its specific design and shape in this preferred embodiment. The control lever is further triggered into the lifting position, causing a reverse upward movement of the agricultural apparatus on the three point linkage.
In the event of a plurality of target soil densities that vary dynamically and significantly over short spans of time, what is important is that the efficacy of the closed loop feedback system described above should be such that the Time Constant of the system is reduced. In the absence of. this the efficiency of the working on the soil and the quality of it will not only be sub optimal but will also vary over different parts of the target soil. The Effort Cam, in the present invention,

is designed in such a manner that the Time Constant of the closed loop feedback system, described above, in the present embodiment of the Invention is optimally reduced so as to substantially improve the efficiency and quality of the apparatus working on the target soil, the density and quality of which dynamically varies as the apparatus is put to use. Figure F depicts the modifications done to the CAM curvature of the Effort Cam in the preferred embodiment of the present invention.
In this preferred embodiment of the present invention, the Roller (c) (that triggers the closed loop feedback system to operate the input plunger (d) of the Distributor) has also been optimally redesigned in such a manner that the Spool response time in the lowering direction as compared to the Art is far quicker, resulting in an improved HITCH REGULATION. Figure G depicts the modifications done to the roller design compared to design in the art.
In the preferred embodiment of the present invention, the external Cam is also designed in such a manner that the working angle is reduced from 22 degrees as prevalent in the art to 19 degrees in the present embodiment, resulting in an improved synchronization between the Bracket, Cam and CV Spool. Figure F also depicts modified design over the art of the external CAM design.
The Spring Rate (sensor part of the closed loop feedback system) in the present embodiment is changed from 39.17 kg/mm to 57.84 kg/mm. This results in improved draft load and quick release of load leading to improved Hitch Regulation.
The Flange has also been redesigned in the preferred embodiment of the present invention. See Figure H. In this embodiment, the Negative Stroke is reduced to 3mm from 8 mm in order to avoid excess penetration of apparatus into the target soil. In the present embodiment the main spool will not move in discharge phase and reduce the frequent motion from discharge and neutral positions as present in the art. This also improves the longevity of continuous usage, and allows the invention in its present embodiment to be used continuously over a longer time, reduce the energy expended, and also lead to less heat based dissipation of energy.
Figure I depicts the specific improvement in hitch regulation percentage in the preferred embodiment as compared to the hitch regulation % to force chart. The force range substantially

improves from an existing range of 150 _ to 650 _ in the prior art to a range of 250 _ to 950 _ in the. preferred embodiment, while the corresponding hitch regulation % range of 78% to 25% in the prior art drops to a range of 58% to 20%. This is a substantial improvement over the Art.
The principle of the. invention remaining te same, the forms of embodiment may vary widely with respect to those described and illustrated, without there by departing from the scope of the present invention.

WE CLAIM:

A preferred embodiment of a hydraulically driven integrated distributor and lifting mechanism for improved control over the Art of movement and effort for positioning a plurality of mounted apparatus for agricultural applications
A distributor and lifter according to Claim 1, in which the Huch Regulation percentage is optimally lower than the Hitch Regulation percentage present in the Art.
A distributor and Lifter according to Claim 2, in which the time constant for responsive operation to varying soil density is optimally lower than that in the present Art
A distributor and Lifter according to Claim 3, in which the main spool will not move in discharge phase and reduce the frequent motion from discharge and neutral positions as present in the art.
A distributor and Lifter according to Claim 4, in which synchronization between the Bracket, Cam and CV Spool is optimally improved as compared to that in the Art.
A distributor and Lifter according to Claim 5, in which draft lead and quick release of load are improved as compared to the Art, leading to improved Hitch Regulation.
A distributor and Lifter according to Claim 6, which can be efficiently used to work a plurality of target soil of a plurality of densities and types without requiring any changes