nited States Patent [72] inventor [21] Appl. No.
[45] Patented [54] SONIC SOIL TILLER AND ROCK REDUCER Claims, 2 Drawing Figs.
[52] U.S. Cl 172/40, 37/D1G.18,171/51,171/71, 241/83, 241/266, 299/14 [51] Int. Cl ..A01b /00,
' 'E21c 37/20 Field of Search 241/84, 94,
95, 101, 264, 266, 206, DIG. 25; 259/DIG. 44;
172/40,766; 165/345; 51/D1G. 11; 73/672, 67.3, 67.4; 209/1, 3; 84/404, 405, 408, 409; 171/51, 83, 77, 71; 37/D1G. 18, 2; 299/14; 241/217, 218, 267,
56T A nzre'rencs Cited UNITED STATES PATENTS 3,131,878 5/1964 Bodine, Jr. 241/262 3,527,501 9/1970 Shatto, .lr 173 /49 X 76,438 4/1868 Graves 171/77 789,892 5/1905 Walker..... 241/ X 1,254,192 1/1918 Bartley 241/84 2,302,801 11/1942 Powelson 37/2 2,633,781 4/1953 Day 94/48 2,970,660 2/1961 Bodine,Jr. 173/49 X 2,986,294 5/1961 Granryd 214/ 3,030,715 4/1962 Bodine 172/40 X 3,033,158 5/1962 Bodine,.lr. 116/137 3,076,547 2/1963 Bodine, Jr. 209/20 3,163,945 1/1965 Dooley 37/2 3,231,025 1/1966 Bodine 172/40 3,448,813 6/1969 Rogers 172/40 3,463,549 8/1969 Goodmam... 299/14 X 3,498,384 3/1970 Ogura...., 172/40 1,693,806 12/1928 Cady 84/409 X 2,247,960 7/1941 Michaels 84/409 FOREIGN PATENTS 99,517 2/1962 Norway 37/2 Primary Examiner-Robert E. Pulfrey Assistant Examiner-Clifi'ord D. Crowder Attorney-Sokolski & Wohlgemuth the vibration of the two plates by the oscillator crushing rocks and soil picked up by the tines.
PATENTEDUU 19 I9" I 3.6135799 SHEET 2 UF 2 g) Y INVENTOR. 258, 1 GBodme SONIC SOIL TILLER AND ROCK REDUCER This application is a continuation in part of my application Ser. No. 460,628, filed June 2, 1965, now U.S. Pat. No. 3,410,351, which patent is a continuation-in-part of my prior application Ser. No. 326,419 filed Nov. 27, 1963, now U.S. Pat. No. 3,269,039, which patent in turn is a continuation-inpart of my application Ser. No. 163,802 filed Jan. 2, 1962, now abandoned, which was a division of my application Ser. No. 839,196 filed Sept. 1959, now U.S. Pat. No. 3,030,715.
In tilling or cultivating farm land a continual problem results from the occurrence of rocks which are embedded in the soil. The rocks are often a severe problem in plowing since they can cause damage to the plow. In some instances the rocks can even cause the plower to come to a complete stop. Even when such rocks are successfully removed the tillage condition of the ground is often ruined as the rocks tear through. The rocks that are not removed successfully remain in the ground at the surface thereof and cause problems in other phases of farming such as planting and harvesting. Thus as can be readily appreciated the rocks present both a hazard and a nuisance, as well as having overall detrimental effect on successful farming.
In the past rocks that have not been removed by the plow have necessitated continuous hand removal. This involves the operator frequently stopping the plow, getting off and actually lifting the rocks and throwing them onto a vehicle so they can be hauled away from the field. Hand labor is extremely costly in farm operations, and certainly is a wasted effort when used for nonproductive function such as rock removal.
Thus itis an object of this invention to provide a device for readily dislodging rocks from engagement with the soil.
A further object of this invention is to provide a device for easily bringing rocks to the surface of the soil being plowed.
One further object of this invention is to provide a device for breaking rocks into small pieces and dropping them back to the ground so that they can be readily assimilated by the earth.
The above and other objects of this invention are accomplished by the herein device which sonically activates the soil to cultivate and fluidize, it, as well as crush rocks that are brought to the surface. This is accomplished by utilizing a tuning fork effect. The device of this invention which can be attached to the front of a tractor or the like farm implement is comprised of a first broad solid plate of elastic material such as steel. Attached to this plate is means for vibrating it such as an orbiting mass oscillator. This first plate is for general disposition above the ground being plowed.
Coupled to the first plate through bolts or other suitable means is a second plate preferably comprising a plurality of individual tines for engagement with the ground. The tines diverge away from the point of affixation to the first plate downwardly toward the earth. When the oscillator vibrates the first plate the tines vibrate oppositely in the manner of a tuning fork due to the acoustic coupling with the first plate. As the vibrating tines engage the earth they fluidize the soil, cul tivating it. Additionally, rocks are scooped up by the tines and fed to the diverging area between them and the first plate. The vibrations of the two elements in the divergent area cause the rocks to fracture and fall to the ground again in the area between the individual tines.
It is believed the invention will be better understood from the following detailed description and drawings in which:
FIG. 1 is a partially sectioned view of the device of this invention affixed to the front end of the tractor; and
FIG. 2 is a top view of the device of this invention.
It has been found most helpful in analyzing the operation of the device of this invention to analogize the acoustically vibrating circuit involved to an equivalent electrical circuit. This sort of approach to analysis is well known to those skilled in the art and is described, for example, in chapter 2 of Sonics," by Hueter and Bolt, published in 1955 by John Wiley and Sons. In making such an analogy, force F is equated with electrical voltage E, velocity of vibration u is equated with equated with electrical impedance Z,..
Thus, it can be shown that if a member is elastically vibrated by means of an acoustical sinusoidal force F sinwt, (to being equal to Zn times the frequency of vibration), that Where wM is equal to 1/mC,,,, a resonant condition exists, and the effective mechanical impedance Z,,, is equal to the mechanical resistance R,,,, the reactive impedance components (0M and llwC cancelling each other out. Under such a resonant condition, velocity of vibration u is at a maximum, power factor is unity, and energy is most efficiently delivered to a load to which the resonant system may be coupled.
It is to be noted that in the device of this invention the mass and compliance for forming the resonantly vibrating system are furnished by the structural members of such system themselves so that the earthen forrnation is not incorporated as a reactance in such system. The earth under such conditions acts as a resistive impedance load which provides no signifi cant reactive components. This employment of apparatus resonance results in a random vibration of the earthen particles rather than a lumped coherent vibration such as results from nonresonant vibrating apparatus, with a considerable relative motion occurring between the separate grains. It is believed that each of the individual irregular grains when energized by the sonic energy in this sonic resonant fashion separately vibrates in a random path with a relatively fixed radius of vibration which changes in direction but remains fixed in magnitude. Such random vibration effectively separates the particles so that they do not adhere to each other. The net result is a uniquely high degree of fluidization of the earthen structure.
It is also important to note the significance of the attainment of high-acoustical Q" in the resonant system being driven, to increase the efficiency of the vibration thereof and to provide a maximum amount of energy for the cultivating operation. As for an equivalent electrical circuit, the 0" of an acoustically vibrating circuit is defined as the sharpness of resonance thereof and is indicative of the ratio of the energy stored in each vibration cycle to the energy used in each such cycle. 0 is mathematically equated to the ratio between (0M and wR Thus, the effective Q of the vibrating circuit can be maximized to make for highly efficient, high-amplitude vibration by minimizing the effect of friction in the circuit and/or maintaining the effect of mass in such circuit.
In considering the significance of the parameters described in connection with equation (1), it should be kept in mind that the total effective resistance, mass, and compliance in the acoustically vibrating circuit are represented in the equation and that these parameters may be distributed throughout the system rather than being lumped in any one component or portion thereof.
It is also to be noted that an orbiting mass oscillator may be utilized in the device of the invention that automatically adjusts its output frequency to maintain resonance with changes in the characteristics of the load. Thus, in the face of changes in the effective mass and compliance presented by the load, the system automatically is maintained in optimum resonant operation by virtue of the lock-in" characteristics of the unique orbiting mass oscillator. The vibrational output from such an orbiting mass oscillator is generated along a controlled predetermined coherent path to provide maximum output along a desired axis or axes. The orbiting mass oscillator automatically changes not only its frequency but its phase angle and therefore its power factor with changes in the impedance load to assure optimum efficiency of operation at all times.
The cultivating effect of the device of this invention results from the high-energy sonic action which generates, as indicated above, a fluidizing-type condition in the soil. The fluidization is accomplished to such a degree since the soil is not required to present any reactance. For example, in a bodily vibration device such as a simple oscillator connected to a cultivator, the soil will present a capacitive response in order to meet the inertia mass of the vibrating cultivator. This limits the conventionaltype vibrators utilization since the soil grains will then vibrate in unison since they are attempting to present a single capacitive reactance in order to counteract the mass reactance of the device of the tool. In the instant resonant sonic device the elastic resonator tine member, together with the plate acting similar to a tuning fork, counteracts the inertia of the device all within itself and therefore the soil presents only resistive impedance as indicated. In view of this effect maximum fiuidization will occur. Further, the rocks are being forced up into the convergent area where the tine member meets the plate member subjecting them to considerable vibratory energy. This serves to crush the rocks by the time they reach the point where the two vibrating members are joined. The crushed rock falls between the tines back to the ground.
Turning now to both FIGS. 1 and 2, there is seen the front portion 11 of a conventional tractor. Pivotally connected at 13 to a support point 15 adjacent I-beam structure 17 of the frame of the tractor is an outwardly extending beam 19. The beam 19 is rigidly affixed at the end opposite from the pivot point 13 to a secondrectangular beam 21 which is transverse thereto. Thebeam 21, as will be shown and explained, serves as the main support for the device of this invention. Affixed tobeam 21 are twobrackets 23 to whichhydraulic pistons 25 are affixed. The opposite ends of eachhydraulic piston 25 are attached torigid support structure 28 mounted at the front of the tractor. By actuating thepistons 25, through means not shown, such as a hydraulic pump or the like, it can readily be seen that therectangular beam 21 can effectively rotate about pivot point 13, thus positioning the tool.
Rigidly affixed to the top of thebeam 21 at the midportion thereof, is a mountingbracket 26 supportinggasoline motor 27. Extending along and rigidly attached to the entire bottom surface ofbeam 21 is aplate 29 of spring steel. Bolted by bolts 31 to the bottom of the flexiblespring steel plate 29 is ananvil plate 33 which can, for example, have a slight curvature thereto as shown. Disposed onanvil plate 33 is an orbiting mass oscillator 35 aligned withmotor 27. The oscillator 35 can be of the type, for example, shown in FIG. 21 of US. Pat. No. 2,960,314. The oscillator 35 is driven bymotor 27 through thedrive shaft 37.
Disposed belowanvil plate 33 and spaced therefrom by ametal spacer 39 is a second plate 41 having a plurality oftines 43. Thetines 43 of plate 41 are curved away or diverge fromanvil plate 33 toward theground 47. Additionally, as shown, it is preferably that thetines 43 be somewhat longer than theanvil plate 33 so as to substantially engage the earth. It should be noted that thespacer element 39 is less than theopenings 45 between the tines so that particles such as 49 located adjacent to the spacer element would not become stuck therein but rather will drop through theopenings 45 back to the earth.
In the operation of the device thetines 43 are initially retracted to rest on the surface of the ground. This is done by withdrawing thepiston 25 to liftbeam 21 and affixed equipment above the soil. Thetines 43 are gradually lowered to the ground as the tractor is moved forward. Themotor 27 is concurrently started causing the oscillator 35 to rotate. In turn,upper plate 33 affixed to the oscillator is vibrated whereas the bottom plate 41 comprised of thetines 43 together with solidupper plate 33 acts as an elastically resonant tuning fork structure. As the tines work their way into the ground they encounter radically different changes of environmental conditions. Therocks 49 are worked to the surface and move along thetines 43, as shown, being crushed in the vibrating area between theupper plate 33 and lower vibrating plate 41. The
orbiting mass oscillator 35 works in conjunction with the tuning fork structure and automatically accommodates for the large changes in reactive and resistive impedance. This is important since the sizes and hardness of the rocks and ground encountered constantly change as the machine progresses across the field.
The tuning fork structure, as shown, is particularly advantageous since the structure can be balanced so that it can be mounted at a nodal point 51 as shown on the wave pattern 53. Since the node is the point of minimum vibration, this feature eliminates the need for a special attachment to isolate the vibrations from the rest of the tractor. Since the vibrations are so minimal at the nodal region a moderately resilient mounting means, such as thespring steel plate 29, will adequately suffice to prevent the vibrations from being carried back to he tractor.
Another advantage of the tuning fork-type structure shown is that the rock crusher feature is easily achieved since the two sides of the jaws work toward and away from each other as a fork goes through its resonant tuning fork vibration. By utilizing theflat plate 33 to form one leg of the fork, and a multitine structure 41 to form the other leg of the fork, it is then possible to feed the rocks into the jaw which has a more or less open structure on one side so that the rocks as they are crushed can be dropped down back to the groundv The vibrating tines, as can now be appreciated, quickly dislodge and drop any temporarily locked particles so that the machine cannot be jammed. A further point to be noted is that as the machine progresses forward, rocks are continually fed under pressure back into the area betweenplates 33 and 41 so there is a continual bias force assuring good acoustical coupling of the rocks with the elastic sonic fatigue action achieved.
Although the two plates of the tuning fork arrangement of this invention are slightly curved, it could be appreciated that they could be fiat plates merely being divergent from each other from their point of attachmentv However, it is found that the slight curvature as shown facilitates the movement of rock particles through the area between the plates in a more gradual manner assuring good acoustic coupling. Additionally, though a tine arrangement is specifically shown, the bottom plate can be provided with a plurality of serrations, slots, or holes sufficient to pass the particles of crushed rock and soil.
Iclaim:
1. A device for tilling soil comprising:
a first elastically vibratable member;
a second elastically vibratable member for engaging the soil acoustically coupled to said first member;
said first member diverging from said second member, said second member extending downwardly and forwardly into the ground below said first member to form a scoop for guiding rocks into engagement between said members;
means for simultaneously resonantly vibrating said members in the manner of a tuning fork; and
means connected to said second member for controlling the depth of penetration thereof into the soil.
2. A device for tilling soil comprising:
a first plate;
a second plate for engaging the soil and rocks in said soil, acoustically coupled to said first plate and separated from said first plate;
said first plate diverging from said second plate, said second plate extending downwardly and forwardly into the ground below said first plate to form a scoop for guiding rocks into engagement between said plates;
means for simultaneously resonantly vibrating said plates so as to cause rocks engaged thereby to be crushed,
said second plate having a plurality of openings therein through which the crushed rock can drop.
3. The device of claim 2, wherein the separation of said plates at the point of coupling is less than the size of said openings in said second plate.
4. A device for tilling soil comprising:
said second plate having a plurality of openings formed between said tines through which the crushed rock can drop.
5. The device of claim 4 wherein said means for resonantly 5 vibrating said plates comprises an orbiting mass oscillator coupled to said first plate.