MULTIPLE ROTOR ROTARY TILLER
DEFINITIONS ROTARY EXCAVATOR
A rotary tiller or a rotary excavator or simply a rotavator are terms used to denote an implement normally used in agricultural fields after each harvest to prepare seedbed for sowing by thrashing soil & remains of the previous harvest and mix layers of top soil. It is generally attached to a carrier from which it also receives power.
CARRIER
A carrier is a tractor or any other vehicle, along with various other uses, used to carry implements like rotavator in fields while powering it with the PTO. Some carriers has variable PTO speeds while some offer constant PTO speed only.
ROTARY-EXCAVATING
It is a term used to denote the operation of a rotavator which thrashes soil by rotary action of its blades to dig and mix it thoroughly with different layers of soil, thus unpacking the bound soil particles, which in turn, provides natural aeration to soil.
WALKING-OVER
It is a term used to denote the inefficient operating thing of a rotavator not gaining depth into the soil and the functioning of blades are simply at the surface level while encountering excessively dry conditions. It is called as 'Walking-over1 because of grossly low depth of operation.

BACKGROUND OF THE INVENTION
The background for this invention lies in the demand for one versatile device suiting all field conditions & specific needs and at the same time giving the buyer (or a farmer) a lot of options for himself to try out on the field for getting the desired thing fulfilled. Most of the present devices, however, are failing in one or another aspect and it is usually necessary to wait for conditions to get suitable or to prepare the field with man-force earlier for such devices to be operated seamlessly or to pass such devices a number of times including in orthogonal direction and cross direction for cases in order to achieve even par best results. Sometimes there is no option left but to bum the previous vegetation and clear or distribute the remains manually. So the reduction or elimination of additional cost incurrence by the above-mentioned preparatory tasks would mean a great deal to the farmer (or a buyer) and this is one of the foremost factors that has driven me—the applicant. The novel addition of more than one functional rotors plus the versatile arrangement of blades (allowable) in between rotors and in the same rotor has significantly improved what is already being done and has also allowed operation in conditions which are impossible for efficient and economical functioning of current technology.

BRIEF DESCRIPTION FIELD OF THE INVENTION
The present invention relates to the wider field of Agricultural Machinery and Implements & Earth Moving Implements and, also in particular, the field of Soil-Pulverizing Machinery. This field includes the whole range of machineries, including Robotics and Artificial Intelligence which has a bright possibility in agriculture of the future.
AREAS OF USAGE &. INDUSTRIAL APPLICABILITY
A Rotary-Excavator finds use in almost all kind of fanning process in preparing the soil-bed for sowing after each harvest. Another collateral happening here in the process is the mixing of the remains of previous vegetation with soil (which would be useful for natural microbial propagation) and better aeration of the soil. Also there is a possibility for using it in earth-rendering and levelling purposes.
ADVANTAGES
Seamless operation under a range of conditions as the device is unlikely to be
interrupted by clogging, 'walking-over" and the likes.
Increased part life and hence reduced maintenance cost, which means an overall
lesser running cost per unit time.
Possibility for an operator to try various things (combinations of arrangement
patterns) in the field itself for need-specific operations.
More penetration and finer pulverization of soil even in drier conditions compared to
other ordinary devices of same field.
Elimination of the need to prepare the field beforehand with labor-force and thus the
overall expense for land-holder per unit area.
Quicker completion time as the number of passes required to render the field with
desirable consistency is grossly reduced (almost to one).
Elimination of the need to pass the device second time in the direction orthogonal to
the first.

PRIOR ART
The current status of the technology in the field of Agricultural Machinery and Implements, and in particular the field of Soit-Pulvehzing Machinery, is that there has been no basic change or innovation in the layout, thrashing apparatus, countering attempts to prevent clogging of rotors by mud and highly fibrous vegetation, elimination of 'walking-over* effect, mud accumulation in the spacing between housing and the blades, if operated in wet conditions and so on and so forth. Also the operation of these Prior Art devices (known to me—the applicant) is highly specific to the conditions normally encountered which means they simply cannot operate in fields with remains of highly fibrous vegetation such as Hibiscus cannabinus or in fields which are excessively drier, if operated, will not gain depth and will simply 'walk-over*. In such times, a land-holder has to wait for the conditions to get right for them to operate. The problem is not only that there is no apparatus to counter-act in such cases, but there is no variability allowable in such a machine (in terms of blade arrangement pattern) for the operator oneself to try-out. What it takes to gain depth into & pulverize and mix layers of the soil and thoroughly thrash whatever vegetation it encounters, is not simply in the design of any other Rotary-Excavator. Generally, these Prior Art devices are required to be passed a number of times in the same area including in the direction orthogonal to the first, to achieve even marginal results. Another usual case is the accumu)ation in the clearance space between housing and the rotating blades (which is low in almost all machines (known to me—the applicant)) resulting in rapid wearing of blade surfaces by abrasion between blades and mud hardened over time.

SUMMARY OF THE INVENTION
My present invention of highly improved form of rotary tiller performs highly efficient
Pulverization of soil.
Thrashing and mixing of weeds and remains (residual stumps) of previous harvest
into the soil.
Mixing of layers of the topsoil together for the preparation of seedbed.
Rotary-excavating enough depth of the top soil to facilitate natural aeration &
microbial propagation and easier manual or mechanized plow afterwards.
(which are the functions of a rotavator primarily) in fields that are as challenging as below:
Wet that the space between rotor flanges and blades and also the space between
the hull and rotor blades is filled up by the cohesive mud.
Having residual stumps of harvested fibrous plants (e.g. Hibiscus cannabinus) that
the rotor gets highly accumulated around.
Having soil types like Black soil, Clay soil etc., that offer high resistance for the
rotation and functioning of blades.
Having residual stumps of harvested non-fibrous plants that the thrashing is either
improper or completely inefficient.
Excessively drier that the device's operating depth is grossly insufficient to provide
a healthy natural aeration to soil
That this may be accomplished, there is utilized a housing with bigger clearance in which two (or more) bladed rotors are driven either independently and separately by the carrier PTO or by the drive received from rotor preceding or succeeding it to cut up vegetation of all forms and render the earth of desirable consistency despite the challenging conditions stated above from (-1 to -5). Also, we introduce the term 'Relative Blades Arrangement' to imply the pattern of blades' placement within the same rotor and in between the succeeding rotors as well (in relation to the preceding one). Another term needing contextual explanation is 'Clearance' which means the vertical distance between the blades and the roof of the housing at its minimum. The bigger clearance of our invention ensures that, while running in fields with residual

stumps of harvested fibrous plants and excessively wet soil, clogging of rotors is not likely to occur.
In accordance with our invention, the blade arrangement of our multi-rotor rotavator capable of cooperating among themselves i.e. the controlled and intentional interference given to individual regions of blades' operation between successive rotors are effective enough to perform its primary functions (-1 to ~4) and other things as well. Whatever a preceding rotor takes or uproots from the earth will be again under the rotational action of the succeeding rotor which enables the device to thrash as well as pulverize vegetation and soil effectively. To explain more dearly, the rotational action is simultaneous in nature, i.e. the material taken up by the forward rotor is not simply thrown to the succeeding one but the succeeding rotor pulls it forcibly from the forward rotor. So, there is this time gap where a piece of vegetation or mud or anything is subjected to a push-pull kind of action of two rotors resulting in thorough thrashing. Also, as I claim, the larger area of the instantaneous operating region (due to presence of more than one rotor) along with the one-of-a-kind distribution of blades (which shall be explained in coming pages) results in more penetration into the ground thereby accomplishing many of its primary functions I mentioned above. While operating in excessively dry fields, where there is chance of slipping of wheels of the carrier, the presence of more than a single functional rotor and the availability of a higher area instantaneous operation prevents it from 'walking-over1 the soil level without Rotary-excavating. The allowable variability in this novel rotavator also aids in here as different rotor speeds mean a resultant load lesser than produced by rotors of same speed in the carrier vehicle.

OBJECTS
It is an object of the invention to provide a rotary tiller capable of performing the primary functions (-1 to -4) even while encountering challenging conditions as stated in (-1 to -5) effectively.
It is another object of the invention to provide a novel rotary tiller that requires to be operated only for a minimum number of passes including in orthogonal directions through a field to render it level and suitable for immediate planting, thus to be time-saving, cost-efficacious and continuous.
It is yet another object of me (—the applicant) to provide a versatile mechanism that would suit operation under all types of soils and conditions in an effective manner. It is still another object of the invention to provide, or more clearly, to allow variability in Relative Blades Arrangement and speed & direction of individual rotors and their rotation respectively an operator oneself can try out on field. It is yet still another object of the invention to eliminate additional costs incurred to a farmer (buyer) in preparing the field beforehand manually along with the actual operating expenditure, in case, by an ordinary rotary excavator.

INDEX OF FIGURES
(For convenience sake, figures presented are for a device that contains two rotors only and thence claimed for its full intentions. Also the element names are marked distributed in many figures instead of one to avoid congestion.)
Fig 1: Perspective view of a multi-rotor rotavator in accordance with our invention.
Fig 1 A: Perspective view that has been partially sectionalized to reveal the presence of more than one rotor inside the housing.
Fig 2: Side view of our innovative rotary excavator exclusively indicating the rotors along with blades mounted to it and its versatility in its arrangement.
Fig 2A: Top view of our innovative rotary excavator exclusively indicating the rotors along with blades mounted to it and its versatility.
Fig 2B: Pictorial representation of the novel blade arrangement shown in fig.2 zoomed to one set of interfering blades in subsequent rotors as viewed from top.
Fig 3: Front view showing the bigger clearance given to the housing which is greatly needed for avoiding accumulation of mud in the space between the hull and rotor blades is filled up by the cohesive mud that hinders the continuity of the effectual-run.
Fig 4: This figure illustrates our novel device receiving power from tractor PTO and transmitting it to the rotors & Fig 4A: The other way the power flow shown in fig.4 can happen.
Fig 5: Exploded view of the device revealing the assembly information of individual parts.

DETAILED DESCRIPTION
Turning to fig. 1, it will there be seen that I have illustrated a multi-rotor type tiller of the type to be drawn through a field or farm by a tractor or any other appropriate vehicle (not shown). This illustration in particular, depicts such a multiple-rotor rotavator that has two functional and powered Rotors R1 and R2 mounted with L-blades. The power flow path, i.e. the transmission mode and u'via-which' components", of this specific device (elucidated here) follows that of the one as given in fig.4 for a device adapted to a tractor PTO. The Housing roof H serves as a seat for Gearbox G and two Side-plates S-RH and S-LH are bolted to it. The Input shaft I of the Gearbox is driven by carrier PTO and it ends with a bevel gear that meshes with the pinion of the Jack shaft J transmitting the power from input shaft to two Output shafts O-RH and O-LH which are coupled to it at its ends. The Side-plates has Chain-housings welded to it each and both the two Chain-housings have a top sprocket connected to the respective output shaft and a bottom sprocket connected to the respective rotor. The sprockets are positioned in the side plates using suitable bearings and are chain-linked. Varying number of teeth in top or/and bottom sprockets is one another way to change rotational speed of rotors and thus the differential rotors' speeds are achieved. Fig.lA, as mentioned above, illustrate the presence of additional rotor and other things clearly. The Housing roof H is made of mild steet sheet of necessary thickness whose frame is consisting of two pipes of square cross section running in between a pair of plates in common to which the Side-plates S-RH and S-LH are attached with bolts on respective sides. The material used (in this case) throughout is Mild Steel except the Gearbox (body) G, all Rotors and Rotor flanges R1-1 to R1-7 and R2-1 to R2-7 [note: fig.2A] which are made of Cast Iron and all powered shafts (bevel of Input shaft I, pinion of Jack shaft J, output shafts O-RH and O-LH) at the milled regions are case-hardened for improving their hardness properties so as to withstand shock loads and other incurrences while on tough soil conditions.
Turning now to fig.2 and fig2A where the fully-functional Rotors R1 and R2 are exclusively shown as viewed from side and top respectively, it becomes clear that not all the flanges are (necessarily) mounted with blades and it also shows that they

are not (necessarily) having blades with their L-planes directed towards the same Side-plate S-RH or S-LH. Confining ourselves to this illustration singularly where there is seven flanges in each rotor, it can be seen that the front Rotor R1 has blades mounted in R1 -1, R1 -3 and R1 -5 and R1 -7 at four places (at odd-numbered flanges) while the second Rotor R2 has blades mounted in R2-2, R2-4 and R2-6 (at even-numbered flanges) at three places. This ensures: 1 That while there is more area of instantaneous operation, the number of blades operating simultaneously in it is lesser which results in more depth of rotary-excavation [see: ~4 and -5], 2.That while there is no region operated more than one time (since a blade-mounted flange doesn't have another blade-mounted flange straight before or after it), there is a shorter possible distance between Rotors due to this 'odd-even arrangement'. From fig.2B pictorially representing the novel blade arrangement shown in fig.2 zoomed to one set of interfering blades in subsequent Rotors as viewed from top, it is easy to infer the intentional interference given to the blades from the intrusion of the (imaginary) lines extending the edge E1 and E2 of the blades in both Rotors into one another. According to our invention, this regional interference is useful for a subsequent Rotor (as) R2 (in here) in redrawing the material rotary-excavated by the preceding Rotor (as) R1 (in here) and thus aids in fields 1.Having residual stumps of harvested fibrous plants (e.g. Hibiscus cannabinus) where the rotor gets highly accumulated around and 2.Having residual stumps of harvested non-fibrous plants that the thrashing is either improper or completely inefficient [see -2 and -2]. Also, this versatile pattern of blades placement in between the Rotors has another effect of 'pulling' the adapting vehicle with its load of added penetration into the ground and so it can be safely stated that this effect eliminates the walking-over of the device in fields that are excessively drier [see ~4 and -5]. This also stems from the fact that there is a lot lesser frictional grip for tires to withstand and move in its original speed against that 'push' from an ordinary rotary-tilling appliance in drier conditions.
As is apparent from the front view of our innovative rotavator shown in fig.3, there is a higher Clearance given to the blades from the housing roof H. The term 'Clearance' is defined already in the summary and a bigger Clearance is provided in our

invention so as to avoid mud getting bound in the space between hull and Rotor blades while functioning in wet fields to a depth where it would start interfering in the circle traced by Rotor blades. The fact in an ordinary rotary tiller is that the cohesive mud that gets attached to the hull and growing downwards with further throwing up, the mud gets dried over time and when it reaches down to the blades of Rotors R1 and R2 at clearing level (as defined), the blades will have to run sliding over it, opposing the resistance given by the mud which would result in more rapid wearing out of the blades. Thus by presenting more space in between the main frame of Housing roof H and a blade edge E1 or/and E2 when the blade is at 12'0 clock position in the side view as in fig.2, the problem mentioned above can be eliminated [see -1 and '2]. Now directing our attention towards fig.4 and in comparison with the explanations for fig.2, it is to be noted that the speeds of individual Rotors can be varied by adjusting the number of teeth in top or bottom sprocket in the needed one of the Chain-housing in the Side-plate S-RH or S-LH. Thus by varying the speed of preceding or following Rotor R1 or R2, the redrawing rate can be varied according to the situation thus giving variability ['4]. Variation is also possible in blade configuration in the Rotors according to the demand. That is, the blade arrangement can also be converse to what was just explained above so that the front Rotor R1 has blades at three places and the second one R2 has blades at four places. The configuration is to be opted by the operator himself as a part of giving the operator options to try out from at various environments. Another thing is that the direction of rotation of Rotors R1 or R2 with respect to the other is not to be necessarily the same and they can be made to rotate in preferred direction (clockwise or counter¬clockwise as viewed from Side-plate S-LH or S-RH) to intentionally effect the rotary-excavation in terms of its redrawing and course of the excavation in particular. This point can be understood by studying fig.2A again. Likewise, from fig.4A, the alternative power transmission path from the Gearbox G to the Rotors is shown which has no big effect in terms of functioning as much as in decreasing the overall width of the device purportedly. For instance if the power flows from the Rotor R1 to R2 unlike in first case, there lies no need for two Chain-housings in both Side-plates S-RH and S-LH which can be replaced by one in either of the Side-plate or in center

of the Rotors (compromising for leaving some space not operated by the rotavator due to absence of blades) thereby reducing the overall width of the device as said earlier.
The apparatus and arrangement used in Rotors preventing mud and soil particles and dust getting into bearing functionaries are clear from the exploded view of the device revealing the assembly information of individual parts (fig.5). There are two depth-control billets (not shown in figures) given on both Side-plates to limit the operating depth so that the implement is not too much penetrated than enough that the economy of adapting vehicle is unaffected. This implement has been fabricated with pipes of square and circular cross section, L-angles and bent plates all with a slightly higher thickness than needed actually or than that of the standard parameter given in other ordinary implements. The reason behind this is to smother the vibrations that naturally arise in any device with Rotors rotating at high speed by the point that the added metal weight absorbs most of the vibrational energy within it. Vibrations stem from eccentricities in Rotors and shafts, errors in horizontal level of Rotor bearings in Side-plates, Gearbox running and chiefly the uneven terrain which brings about uneven load to the blades and hence to entire bearing and meshing components. All the external parameters of the device elucidated here varies according to the Horsepower of the adapting vehicle and these parameters include Tractor power, Overall Width, Overall Height, Tillage Width and the rest.
NEED SPECIFIC VARIATIONS IN ROTOR SPEEDS AND DIRECTIONS
An operator can make the following changes in terms of direction of rotation in the present invention (elucidated by the figures) due to presence of more than one rotor:
a. Both the rotors rotating in the same direction as in direction of the rotation of wheels
of the carrier moving in forward direction.
b. Both the rotors rotating in the same direction opposite to the rotation of wheels of
the carrier moving in forward direction.
c. Both the rotors rotating opposite to one another in a way that they, viewed from left
as in Fig.2, throw material toward one another.

d. Both the rotors rotating opposite to one another in a way that they, viewed from left
as in Fig.2, throw material away from one another.
These variations tried in combination with the variations available in Blade Arrangement Pattern (Relative Blade Arrangement) gives rise to more number of methods with which the device can be operated. Also is the variability that is allowed in terms of speeds of rotors (Relative Speed) as following:
e. Both the rotors rotating in the same speed.
f. The preceding rotor rotating at a higher speed.
g. The succeeding rotor rotating at a higher speed.
With these (e, f, g) tried in combination with what already had been stated (a, b, c, d) along with the Relative Blade Arrangement methods, the number of variability gets manifold. These find much use especially in extreme conditions of soil: excessively wet or excessively dry.
EXAMPLE-. While operating on a dry field, where there is high chance for carrier wheels to slip, the rotors may be made to rotate opposite to one another thus producing a net pull on the carrier or rotate at different speeds or rotate opposite to rotational direction of carrier wheels or in the combination of these.