Abstract:
An adjustment mechanism for use with farm implements or other equipment utilizes a series of alternating teeth and notches arranged in an arcuate pattern about an axis of adjusting movement on a movable member and a pair of arcuately spaced latching bars on a stationary member of the mechanism. The bars are individually shiftable into and out of engagement with the teeth and notches and are spaced apart such a distance that when either of the bars is in registration with a notch, the other bar is in registration with a tooth. Springs yieldably bias the bars toward the teeth and notches so that the bar aligned with a notch will snap down into the notch while the other bar resides in a standby position abutting the outer end of its tooth. When the seated bar is manually withdrawn from its notch, the movable member becomes unlatched and is free to be indexed one increment in either direction about the adjustment axis, whereupon the bar in the standby position snaps down into a notch brought under that bar, reestablishing a latched condition while the withdrawn bar becomes retained in its standby position by the outer end of its tooth. A double-acting lever having two fulcrum connections with the bars at their outer ends is successively raised and lowered about alternate ones of the fulcrum connections to manipulate the latching bars.

Description:
TECHNICAL FIELD 
     The present invention relates to farm equipment and, more particularly, to an adjustment mechanism having particular utility for quickly and easily adjusting the position of one part of a tool, such as a cleaning tine or gauge wheel of a coulter assembly, relative to another part of the tool, such as the coulter blade of the assembly. The invention is especially well-suited for large tillage or planting machines having many separate furrow opening units across the width of the machine, all of which must be uniformly adjusted. 
     BACKGROUND 
     Mechanisms and devices for adjusting and releasably retaining various components of farm equipment tools in selected positions of adjustment are well known in the art. However, many such mechanisms require the use of hand tools for making the adjustments, and many are rather tedious and time-consuming to use. Furthermore, many are not particularly precise. 
     Large, wide tillage and planting machines present particular challenges because they may be provided with fifty or more separate opener units that must all be maintained at the same setting. For example, if a slightly different running depth is desired for the coulter blades or other furrow opening devices of the machine, the gauge wheel of each and every opener on the machine must be adjusted before the machine can begin operations. Moreover, with conventional adjustment devices, it may be difficult to assure that each opener is set to the same depth. 
     SUMMARY OF THE INVENTION 
     The present invention provides an adjustment mechanism that can be operated quickly and easily without the need for hand tools. It also provides for relatively precise adjustments without sacrificing structural strength and sturdiness, which can be especially important in those applications where the device may be subjected to harsh conditions and heavy loading such as found in tillage and planting operations. 
     In a preferred embodiment of the invention a stationary part of the mechanism supports a movable part for pivotal adjustment about an axis of adjustment. A series of alternate teeth and notches on one of the parts are arranged in an arcuate pattern about the axis of adjustment, while a pair of arcuately spaced latching bars on the other part are adapted for independent movement into and out of engagement with the teeth and notches. The spacing between the latching bars is such that when either of the bars is in registration with a notch, the other bar is in registration with a tooth. Thus, by spring-loading both bars, one of them can be seated within a notch to retain the movable member in a selected position of adjustment while the other is maintained in a standby position abutting the outer end of a neighboring tooth. To change the position of the member by one increment, the seated bar is withdrawn from the notch and held against reinsertion, which releases the movable member. When the movable member is indexed one increment, the bar in the standby position snaps down into a notch now brought into registration with it and reestablishes a latched condition in the new position of adjustment. The previously latched bar can now be released to reside in a standby position spring-biased against the outer end of a tooth. 
     In an especially preferred embodiment, the teeth and notches are on the movable member, while the spring-loaded latching bars are on the stationary member. Further, a single actuating lever is connected to the two bars in such a manner as to facilitate withdrawal of a seated bar from a notch and to temporarily retain it in a withdrawn condition until the movable member has been indexed by one increment and the withdrawn bar is now retained in the standby position by the outer end of a tooth. The connection of the lever to the bars is in the nature of a pair of separate fulcrum connections that enable the lever to fulcrum about alternate ones of the bars in a pumping-like lift and lower action as the movable member is adjusted through successive increments. 
     The invention may be advantageously incorporated into a tillage or planting machine where many separate, individual opener assemblies across the width of the machine are provided. The movable member on each opener assembly may have a cleaning tine associated with it whose position relative to a coulter blade may need to be adjusted to provide optimum field operations. Alternatively, the movable member may have a gauge wheel associated with it that determines the depth of penetration of the coulter blade into the soil such that adjustment of the gauge wheel relative to the coulter blade correspondingly adjusts the depth of penetration. Furrow closing wheels and other structures requiring adjustment could alternatively be associated with the movable member. 
    
    
     DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a right side elevational view of one exemplary embodiment of the present invention the particular apparatus chosen for exemplary purposes comprising a coulter assembly having an adjustable cleaning tine; 
     FIG. 2 is a rear elevational view thereof; 
     FIG. 3 is a left side elevational view thereof; 
     FIG. 4 is a top plan view of the coulter assembly with the mounting bar of the implement frame fragmentarily shown; 
     FIG. 5 is a fragmentary cross-sectional view of the assembly taken along a horizontal cut plane passing through the pivot axis of an adjustable mounting member of the assembly; 
     FIG. 6 is an isometric view of the spring tine of the assembly; 
     FIG. 7 is an exploded isometric view of certain components of the coulter assembly; 
     FIG. 8 is an exploded rear isometric view of certain components of the assembly; 
     FIG. 9 is a fragmentary side elevational view of the adjustment mechanism associated with the coulter assembly; and 
     FIG. 10 is a fragmentary side elevational similar to FIG. 9 but illustrating the adjustable indexed one increment from its position in FIG.  9 . 
    
    
     DETAILED DESCRIPTION 
     The present invention is susceptible of embodiment in many different forms. While the drawings illustrate and the specification describes certain preferred embodiments of the invention, it is to be understood that such disclosure is by way of example only. There is no intent to limit the principles of the present invention to the particular disclosed embodiments. It is to be appreciated that while the adjustment mechanism of the present invention is described and illustrated herein in connection with the adjustable cleaning tine of a coulter assembly, the mechanism can also be used advantageously with adjustable gauge wheels and other structures that might be associated with coulter assemblies or other devices. 
     As shown particularly in FIGS. 1-4, a coulter assembly constructed in accordance with the principles of the present invention is broadly denoted by the numeral  10  and is adapted for attachment to the frame  12  of a farm implement (not shown). A U-bolt clamp assembly  14  accomplishes this function in the illustrated embodiment. Coulter assembly  10  in FIG. 1 is illustrated as moving from left to right during field operations, as well understood by those skilled in the art. 
     The coulter assembly  10  includes an upright tubular support  16  of generally rectangular cross-sectional configuration, such support  16  being adjustably received within and secured to a collar  18  that is in turn clamped to the frame  12  by the U-bolt clamp assembly  14 . At its lower end, support  16  has a yoke  20  presented by a pair of laterally spaced apart, downwardly and rearwardly extending ears  22  and  24  (see also FIG.  8 ). Ears  22  and  24  are provided with a pair of corresponding holes  26  and  28  (FIG. 8) that are transversely horizontally aligned for the purpose of receiving a pivot bolt  30  defining a first transverse axis of swinging or pivoting movement as will hereinafter be further described. 
     Pivotally attached to yoke  20  via bolt  30  is a generally U-shaped carrier  32  (see FIG. 8 in particular) comprising a pair of laterally spaced arms  34  and  36  that are rigidly interconnected adjacent their forward ends by a transversely extending, cylindrical hub  38  welded at its opposite ends to the arms  34 , 36 . As shown in FIG. 8, hub  38  houses a tubular spacer  40  on bolt  30 , as well as a pair of bushings  42  and  44  on opposite sides of spacer  40 . A nut  46  and lock washer  48  retain bolt  30  and carrier  32  on yoke  20 . 
     A generally flat, sharp-edged coulter blade  50  is rotatably supported on arm  34  of carrier  32 . While arm  34  is disposed in generally perpendicular relationship to hub  38 , the axis of rotation of coulter  50  is not parallel to the axis of up and down swinging movement of carrier  32  defined by bolt  30 . Instead, the axis of rotation of coulter  50 , denoted by the numeral  52  in FIGS. 4 and 5, is cocked forwardly so that it converges toward bolt  30  as arm  36  is approached. Thus, coulter  50  is correspondingly skewed at an oblique angle with respect to the forward path of travel of the implement, presenting a slightly leading or compression face  54  on one side and a trailing face  56  on the opposite side. Thus, as illustrated in FIGS. 1,  2  and  3 , coulter  50  cuts through the soil during field operations and pushes the soil slightly to one side (FIG. 2) to prepare a shallow trench or furrow  58  into which seeds and/or fertilizer may be deposited. In the illustrated embodiment, the coulter assembly  10  selected for purposes of illustration may be termed a “right hand” assembly wherein coulter  50  is angled with compression face  54  on the right side so as to correspondingly produce a slight lift or lip of soil  59  (FIG. 2) as coulter  50  travels through the soil. It will be noted also that coulter  50  is tilted back slightly so the bottom extremity of coulter  50  is somewhat closer to arm  36  than the top extremity. This also results in axis  52  being slightly upwardly and rightwardly inclined as illustrated in FIG.  2 . 
     Carrier  32  and coulter  50  are yieldably biased downwardly by a coil spring assembly  60 . Such assembly  60  includes an elongated, fore-and-aft extending, rigid strap  62  that is anchored at its rear end to a rearward portion of arm  34  and at its forward end passes through a slot  64  (FIGS. 4 and 8) in an upturned abutment plate  66  that is rigidly affixed to support  16  just above yoke  20 . A retainer pin  68  or the like (FIG. 4) prevents strap  62  from pulling back out of slot  64  and keeps carrier  32  and coulter  50  from dropping down beyond a predetermined limit of travel. Spring assembly  60  further includes a coiled compression spring  70  trapped between abutment plate  66  at the upper end and a shoulder  72  at the lower end to provide yieldable resistance to upward swinging of carrier  32  and coulter  50 . 
     Attached to the rear of arm  34  is a scraper assembly broadly denoted by the numeral  74 . Assembly  74  includes a mounting bracket  76  bolted or otherwise secured to arm  34 , and a slightly inwardly curved scraper blade  78  secured to the lower extremity of bracket  76 . Blade  78  is designed to contact trailing face  56  of coulter  50  generally within the second quadrant thereof as viewed in FIG. 3 for the purpose of scraping dirt and mud from trailing face  56  as it begins to lift up and out of furrow  58 . The lowermost edge of blade  78  is angled upwardly and forwardly in a diagonal manner across the lower rear portion of trailing face  56 . 
     A generally upright placement tube  80  is attached to and supported by the rear of bracket  76 , such tube  80  having a lower discharge end  82  that curves slightly downwardly and rearwardly generally in the vicinity of scraper blade  78 . Discharge end  82  of tube  80  is located somewhat above the bottom of furrow  58  and in transverse alignment with scraper blade  78  behind the latter so as to be in a protected position for discharging substances into furrow  58 , such as seeds and/or fertilizer. The upper end of placement tube  80  is, of course, coupled with a source of supply of the materials being deposited in furrow  58 . An upwardly and forwardly angled mounting sleeve  84  is also carried on bracket  76  but substantially outboard of tube  80  for the purpose of supporting an optional discharge tube (not shown) for other substances. 
     A special vibratory cleaning tine  86  is mounted on carrier  32  in a resilient and adjustable manner for cleaning dirt and mud from the compression face  54  of coulter  50  without catching and accumulating trash. Tine  86  is described and claimed in co-pending application Ser. No. 10/185,625 filed contemporaneously herewith and titled Fertilizer Coulter with Trash—Shedding, Vibratory Cleaning Tine. 
     As illustrated in FIG. 6, tine  86  includes two major portions, i.e., an elongated working leg portion  88  and a transverse relief spring coil portion  90 . Working leg  88  includes an upper or forward segment  92  that extends at generally right angles to the axis of transverse coil  90 . Leg  88  further includes an intermediate, inturned segment  94  extending at an oblique angle to the axis of coil  90 , and a working tip segment  96  that projects rearwardly from intermediate segment  94  almost at the same angle as upper segment  92  but preferably inturned slightly with respect to the longitudinal axis of upper segment  92 . 
     Tine  86  is mounted on carrier  32  by a special mount broadly denoted by the numeral  106 . Mount  106  includes an upwardly and rearwardly angled arm  108  that is swingably attached to arm  36  of carrier  32  by a pivot bolt  110  which passes through a hole  112  in arm  36  as illustrated in FIG. 7, such bolt  110  defining a third axis of pivoting or rotational movement. Arm  108  has a cylindrical hub  114  rigidly affixed thereto such as by welding, the hub  114  projecting laterally outwardly from the outboard face of arm  108  and receiving a bushing  116  in concentric relationship to pivot both  110 . Coil  90  of tine  86  encircles hub  114  and is trapped between the outboard face of arm  108  and a fore-and-aft extending leg  118  of a generally L-shaped keeper  120 . Pivot both  110  serves to attach the entire assembly consisting of keeper  120 , bushing  116 , tine  86  and arm  108  to arm  36  of carrier  32 . 
     Tine  86  is mounted on carrier  32  by a special mount broadly denoted by the numeral  106 . Mount  106  includes an upwardly and rearwardly angled arm  108  that is swingably attached to arm  36  of carrier  32  by a pivot bolt  100  which passes through a hole  112  in arm  36  as illustrated in FIG. 7, such bolt  110  defining a third axis of pivoting or rotational movement. Arm  108  has a cylindrical hub  114  rigidly affixed thereto such as by welding, the hub  114  projecting laterally outwardly from the outboard face of arm  108  and receiving a bushing  116  in concentric relationship to pivot bolt  110 . Coil  90  of tine  86  encircles hub  114  and is trapped between the outboard face of arm  108  and a fore-and-aft extending leg  118  of a generally L-shaped keeper  120 . Pivot bolt  110  serves to attach the entire assembly consisting of keeper  120 , bushing  116 , tine  86  and arm  108  to arm  36  of carrier  32 . 
     Tine  86  is oriented on hub  114  of mount  106  in such a manner that working leg  88  is closest to arm  108 , with coil  90  progressively decreasing in diameter as keeper  120  is approached. In a preferred embodiment, the largest convolution  98  is significantly larger in diameter than hub  114  so that convolution  98  does not engage the exterior surface of hub  114 . Likewise, convolution  100  is, for the most part, sufficiently large in diameter that the interior surface of convolution  100  does not engage the exterior of hub  114 . Convolution  102 , on the other hand, has substantially the same internal diameter as the exterior diameter of hub  114  such that convolution  102  physically engages the exterior of hub  114  over a complete 360° of wrap. Tang  104  on convolution  102  projects through and is received within a retaining hole  122  in leg  118  of keeper  120 . A first inturned protrusion  124  on leg  118  bears against smallest convolution  102  to help retain the latter in place on hub  114 , while a second inturned leg  126  of keeper  120  overlies upper segment  92  of working leg  88  and underlies the bottom edge of mounting arm  108  as illustrated, for example, in FIG.  2 . 
     Mount  106  and tine  86  are selectively adjustable about the axis of bolt  110  so as to permit adjustment of the angle of working tine leg  88  relative to the ground. As illustrated in FIG. 1, for example, working tine leg  88  extends generally downwardly and rearwardly diagonally across outer face  54  of coulter  50  just below axis  52 , but that angle can be adjusted as may be necessary or appropriate considering the running depth of coulter  50  and/or the trash flow in the vicinity of tine  86 . Generally speaking, it has been found beneficial to position the working tip segment  96  of tine  86  just slightly above the surface of the ground when coulter  50  is at operating depth. Moreover, it has been found that, in some conditions, tine  86  may more readily shed trash as working leg  88  is less inclined and more horizontally disposed. Mechanism for rendering tine  86  selectively adjustable in this respect is broadly denoted by the numeral  128 . 
     Mechanism  128  includes cooperating, interengageable structure on arm  36  of carrier  32  and arm  108  of mount  106 . Arm  36  comprises a stationary member, while arm  108  comprises a movable member. More specifically, arm  108  at its upper and rearmost end includes an enlarged, generally arcuately configured locking segment  130  provided with a series of side-by-side, alternate teeth  132  and notches  134 . In the illustrated embodiment, a total of eight teeth  132  are provided, along with seven notches  134  interspersed between the teeth. The radially outermost faces  136  of teeth  132  are generally flat or at most slightly convexly radiused, while notches  134  are slightly tapered so as to widen progressively and by a small amount as the deep end of each notch is approached. Teeth  132  are substantially the same size as notches  134 . 
     The other part of adjustment mechanism  128 , i.e., the structure on arm  36  of carrier  32 , includes structure for selectively engaging teeth  132  and notches  134  for the purpose of holding mount arm  108  in a selected position about the axis of pivot bolt  110 . Such structure includes a pair of generally upright latching bars  138  and  140  that are each sized and shaped to be easily received within a selected one of the notches  134 . Latching bars  138  and  140  are spaced apart on the arc of swinging travel of locking segment  130  a distance equaling the combined width of one notch and one tooth and, more particularly, a center-to-center distance equal to three times the center-to-center distance between a notch and an adjacent tooth. Thus, as illustrated in FIG. 1, for example, when the latching bar  138  is aligned with a tooth  132 , the latching bar  140  is aligned with a notch  134  on the other side of the next adjacent tooth. 
     The terms “teeth”, “notches”, and “bars” as used in this description and the claims are intended to be interpreted broadly rather than in a limiting sense. Thus, the term “teeth” or “tooth” is intended to encompass a wide variety of projections and/or surfaces, while the term “notches” or “notch” is intended to encompass a wide variety of different depressions, indentations, holes, recesses and/or cavities. Likewise, the term “bars” or “bar” is intended to encompass a wide variety of different movable pins, shafts, projections, and/or members. 
     A pair of generally vertically spaced, superimposed guide plates  142  and  144  slidably receive the two latching bars  138 , 140  for individual reciprocation thereof toward and away from locking segment  130 , and latching bars  138 , 140  are provided with coil compression springs  146  and  148  respectively for yieldably biasing the bars downwardly toward teeth  132  and notches  134 . Cross pins  150  and  152  in latching bars  138  and  140  respectively trap springs  146  and  148  against the underside of upper guide plate  142  to carry out this function. 
     The latching bars  138  and  140  pass upwardly through and beyond upper guide plate  142  and are operably coupled at that location with a generally fore-and-aft extending operating handle or lever  154 . The forward end of lever of  154  is pivotally connected to the upper end of latching bar  140  via a fulcrum pivot  156 , while the mid-part of lever  154  is operably coupled with the upper end of latching bar  138  via a fore-and-aft slot  158  in lever  154  and a transverse fulcrum pin  160  on bar  138 . The distal end of lever  154  thus functions as a gripping portion to facilitate manual actuation of lever  154 . 
     OPERATION 
     FIGS. 9 and 10 illustrate the manner of use and operation of adjustment mechanism  128 . As illustrated therein, the notches  134  are preferably labeled with suitable indicia such as alphabet letters “A” through “G” to facilitate quick recognition of the particular setting that has been selected for arm  108  relative to arm  36 . Although not shown in the drawings, it is to be understood that a suitable reference point or indicator could be provided on the stationary arm  36  in close association with the notches A-G so that the setting can be visually determined by noting which of the notches A-G is in close proximity to the indicator. For example, lower guide plate  144  could be provided with a downturned, overhanging lip (not shown) disposed outboard of teeth  132  and overlying the teeth and portions of the indicia A-G. A cut-out or window (not shown) could be provided in such lip in registration with the indicia A-G for indicating the selected setting depending upon which alphabet letter is exposed by the window. This type of arrangement would be particularly beneficial on large implements where many separate tools or assemblies need to be uniformly adjusted. 
     FIG. 9 illustrates arm  108  latched by latching bar  140 , which is seated within notch B. On the other hand, bar  138  is maintained in a standby position abutting the outer end of the tooth between notches C and D. Spring  146  associated with bar  138  is in a compressed condition, and the rear end of lever  154  is in a raised position. 
     In order to adjust arm  108  one increment in a clockwise direction relative to arm  36 , lever  154  is grasped and pushed down, causing it to fulcrum about pin  160 , which raises the forward end of lever  154  and withdraws bar  140  from notch B against the resistance of spring  148 . With lever  154  held down in this condition, both bars  138  and  140  are out of the notches, which has the effect of releasing or unlatching arm  108 . Thus, arm  108  may then be grasped with the user&#39;s other hand and indexed one increment in a clockwise direction viewing FIG.  10 . When notch D comes into registration with bar  138 , spring  146  automatically snaps bar  138  down into notch D, re-establishing a latched condition of arm  108  as shown in FIG.  10 . At the same time, the tooth between notches B and C has come into registration with bar  140  such that the outer end of such tooth now functions to retain bar  140  in its standby position as illustrated in FIG.  10 . 
     If an additional increment of adjustment is desired, the rear end of lever  154  is then raised so that the front end fulcrums about pivot  156  and bar  138  becomes withdrawn and unseated from notch D. With arm  108  thus unlatched, arm  108  may be indexed one additional increment in clockwise direction until notch C comes under bar  140 , whereupon spring  148  will snap bar  140  down into seated relationship within notch C. Because the outer end of the tooth between notches D and E comes under the withdrawn bar  138  at this time, bar  38  becomes maintained in its standby position yieldably abutting the outer end of such notch. 
     It will thus be seen that in carrying out the adjustment action, lever  154  alternately fulcrums about different ones of the bars  138  and  140  in successive lifting and lowering motions. If a significant amount of adjustment is desired, several repeated operations of lever  154  will be carried out, the resulting motion somewhat resembling the pumping action that occurs when operating the pump handle of a manual water pump. 
     It should also be apparent that by using a pair of latching bars instead of only one, a finer and more precise adjustment can be achieved. If only a single latching bar is used, the increments of adjustment correspond to the distance between adjacent notches. However, with a pair of bars, mutually spaced so that when one registers with a notch the other registers with a tooth, the increment of adjustment equals one-half the distance between adjacent notches. Yet, this finer adjustment has been achieved without reducing the size of the teeth, which might correspondingly reduce the structural reliability of the device. With the present invention, increased precision is obtained without sacrificing structural strength and sturdiness. 
     With respect to the overall operation of coulter assembly  10  and cleaning tine  86 , it will be appreciated that as coulter  50  rotates through the soil in its furrow-forming action, clumps of dirt tend to adhere to trailing portions thereof as they move up and out of furrow  58 . However, scraper blade  78  continuously scrapes those materials from the trailing face  56  of coulter  50 , while tine  86  performs the same function on compression face  54 . While scraper blade  78  travels in the “shadow” or lee of coulter  50  and is thus essentially shielded from encounters with trash materials, tine  86  is not so protected and is instead fully exposed to trash materials that would tend to catch on working leg  88  thereof and accumulate. However, due in part to the resilient mounting of working leg  88  through spring coil  90 , working leg  88  is constantly undergoing a vigorous vibratory action in a variety of planes that helps it shake free of trash materials that would otherwise cling and build up on the tine. Such action is caused in part by impacts with the trash materials themselves but, in addition, by the clumps of dirt adhering to the face  54  of coulter  50  and passing under the working tip  96  that otherwise always remains in metal-to-metal contact with face  54 . Such encounters of tip  96  with dirt clumps has the tendency not only to flip the tine upwardly, but also to snap it outwardly away from the face of the coulter. Thus, the tine is continuously undergoing a lift and drop action as well as an in and out flexing, all of which has the effect of shaking otherwise clinging trash materials off the tine and on to the ground. Without build up of trash on the tine, tip  96  is free to maintain metal-to-contact with face  54  to provide improved cleaning action without trash build-up. 
     Due to the special design of coil  90 , the spring action of working leg  88  is much more lively than would otherwise be the case. In this respect it will be noted that the two largest convolutions  98  and  100  of coil  90  are essentially open and unstressed when working leg  88  is under no load. Thus, not only is the inherent resiliency of operating leg  88  available over its operating length from hub  114  to working tip  96 , but also the length of wire presented by the unconstricted convolutions  98  and  100  is available to provide a resilient action. Thus, as working leg  88  is forced upwardly out of its nominal position, the two largest convolutions  98  and  100  have considerable space to constrict or contract in a tightening action around hub  114 , thus storing up energy for a snap return of working leg  88  back toward its nominal or equilibrium position once the loading has been removed. Moreover, the open and unloaded condition of the two largest convolutions  98  and  100  allows them to twist and cant inwardly and outwardly as need be to provide for an extensive range of travel of operating leg  88  toward and away from compression face  54  when a transverse loading is experienced by the working tip  96 . Again, this greater range of motion and resilience than would be provided if convolutions  98 ,  100  and  102  were all tightly wrapped around hub  114  provides a more animated action on the part of tine  86  to resist the accumulation of trash materials. 
     Furthermore, this lively action of tine  86  can be obtained at any adjusted position thereof relative to coulter  50  and the ground surface. Regardless of the selected position of mount  106  about the axis of pivot bolt  110 , the performance of coil  90  is unaffected. It will be observed in this respect that coil  90  does not in any way tighten or loosen on hub  114  as mount arm  108  is adjusted. Instead, tine  86 , including both working leg  88  and coil  90 , moves as a unit with mount  106  in the direction of adjustment. In some cases it may be desirable to have working leg  88  more or less angled than illustrated in FIG. 1, but in either case the performance of coil  90  remains the same to provide superior vibratory action. 
     Although preferred forms of the invention have been described above, it is to be recognized that such disclosure is by way of illustration only, and should not be utilized in a limiting sense in interpreting the scope of the present invention. Obvious modifications to the exemplary embodiments, as hereinabove set forth, could be readily made by those skilled in the art without departing from the spirit of the present invention. 
     The inventor(s) hereby state(s) his/their intent to rely on the Doctrine of Equivalents to determine and assess the reasonably fair scope of his/their invention as pertains to any apparatus not materially departing from but outside the literal scope of the invention as set out in the following claims.