Bedding plow featuring a center-cut disk assembly having resilient relief means

A bedding plow suited for forestry planting operations includes a plow frame that is attached to a tractor or other tow vehicle. The frame holds a pair of trailing disk assemblies that are arranged along opposite longitudinal sides of the bed being plowed. A center-cut disk assembly is mounted pivotably to the frame between and forwardly of the trailing disk assemblies. A resilient biasing assembly such as a hydraulic or pneumatic relief mechanism interconnects an arm of the center-cut disk assembly and the frame. The resilient biasing device urges the center-cut disk assembly to engage the ground under normal circumstances and permits the disk assembly to retract upwardly and ride over obstructions that are encountered while the plow cultivates the bed.

FIELD OF THE INVENTION
 This invention relates to a bedding plow and, more particularly, to a
 forestry bedding plow featuring a center cut disk assembly. The disk
 assembly includes hydraulic or other resilient means of relief.
 BACKGROUND OF THE INVENTION
 In forestry bedding operations it is usually desirable to precut a furrow
 as it is being plowed or tilled. This process eliminates, or at least
 reduces re-growth of weeds, competitive trees, grasses, etc. in the center
 of bed and thereby significantly improves the likelihood that planted
 seedlings will survive and thrive. Traditionally, precutting has been
 performed by fixed rippers and similar implements. Plows employing such
 devices normally must be pulled by relatively expensive tractors having
 sufficient horsepower to overcome stumps, rocks and other obstacles
 encountered by the plow. Moreover, when a fixed ripper engages an
 obstruction, the entire plow tends to be disrupted and there is usually a
 significant delay before the plow stabilizes. As a result, part of the bed
 proximate the obstruction may be poorly cultivated or missed by the plow
 entirely.
 As an alternative to fixed rippers, offset harrow type plows have been used
 to precut or center-cut the bed. Also, standard bedding plows have been
 drawn in multiple passes over the bed. These techniques are typically time
 consuming, machinery intensive and quite costly. Virtually all of the
 known techniques for precutting forestry beds have been inefficient.
 Significantly improved efficiency is required, particularly for bedding
 operations in the forestry industry. At the same time, an effective
 center-cut and successful, high yield cultivation must be achieved.
 SUMMARY OF THE INVENTION
 It is therefore an object of this invention to provide a bedding plow that
 effectively precuts a planting bed so that re-growth of competitive trees,
 weeds, grasses, etc. is minimized and successful, high yield planting
 results are achieved.
 It is a further object of this invention to provide a bedding plow which
 center-cuts or precuts a forestry bed in a highly efficient manner and
 which eliminates the need for expensive, complex and high horsepower
 equipment.
 It is a further object of this invention to provide a bedding plow that
 effectively and efficiently performs center-cutting of a forestry bed in a
 single pass, and which eliminates the time and expense required by
 machines that are employed in multiple passes.
 It is a further object of this invention to provide a bedding plow that
 employs a center-cutting disk assembly with hydraulic or other means of
 spring relief that permits the plow to transcend obstructions in the bed
 without causing significant disruption to the plow.
 It is a further object of this invention to provide a bedding plow that
 avoids significant disruption when encountering obstructions in the bed
 being plowed so that the bed is successfully cultivated without
 significant gaps or missed regions.
 It is a further object of this invention to provide a bedding plow that may
 be used particularly efficiently and effectively in forestry applications.
 This invention features a bedding plow apparatus including a frame that is
 selectively attached to and pulled by a tractor or other tow vehicle. At
 least three sets of disk assemblies are mounted to the frame and engaged
 with the bed to be plowed. In particular, the apparatus includes a pair of
 trailing disk assemblies that are attached to and pulled behind the frame
 and disposed along respective longitudinal sides of the bed. Each trailing
 disk assembly includes a trailing arm that is attached at its forward end
 to the frame. Each trailing disk assembly also includes at least one
 trailing disk that is mounted to the trailing arm proximate a distal end
 of the arm. A center-cut disk assembly is attached to the frame between
 the trailing disk assemblies. The center-cut disk assembly includes a
 center-cut arm that is pivotably attached proximate a forward end to the
 frame. At least one center-cut disk is attached proximate an opposite
 distal end of the center-cut arm. A resilient relief mechanism
 interconnects an intermediate portion of the center-cut arm with the
 frame. The resilient relief mechanism urges the center-cut disk assembly
 to engage the bed so that each disk in the center-cut disk assembly
 precuts the bed as the plow is pulled through the bed by the tow vehicle.
 In a preferred embodiment, each center-cut disk is rotatably mounted to the
 center-cut arm. Each center-cut disk may be disposed at a positive angle
 relative to the longitudinal axis of the bed and the plow. The center-cut
 disk or disks are preferably disposed axially forwardly of the trailing
 disks.
 The resilient relief mechanism may include a hydraulic relief device such
 as an accumulator. Hydraulic relief means or other forms of resilient
 relief may interconnect each of the trailing disk assemblies and the
 frame. More particularly, a hydraulic relief mechanism may interconnect
 each trailing arm and the frame.
 An additional implement such as a wheel/packer assembly may be
 interconnected to the frame and pulled behind the plow generally
 rearwardly of the trailing disk assemblies. The frame of the plow may
 include a drawbar and a support portion attached to the drawbar. The disk
 assemblies are connected to the support portion.

There is shown in FIGS. 1 through 3A a bedding plow 10 designed primarily
 for use in forestry bedding applications. The version of plow 10 shown in
 FIG. 1 is almost identical to the version shown in FIGS. 2 and 3A. The
 plows differ only in that they employ slightly different wheel/packer
 assemblies 120, 130. Those respective assemblies are explained more fully
 below. In any event, the use of a wheel/packer assembly is optional and
 plow 10 may be operated without such an attachment.
 Plow 10 includes a frame 12 that is secured in a standard manner to a
 tractor or other type of tow vehicle, not shown. More particularly, frame
 12 includes a drawbar 14 that carries a hitchpin bracket 16 at its forward
 end. The hitchpin bracket is interengaged by a pin, not shown, to the
 tractor in a standard manner. Frame 12 also includes a support portion 18
 that is secured to drawbar 14 by welding, bolts or other conventional
 means. For example, as shown in FIG. 3B the support portion may be
 releasably interconnected to the drawbar by a pair of pins 15, only one of
 which is shown. The frame 12 is composed of steel or other durable metals
 or metal alloys.
 Various plowing attachments are operably interconnected to support portion
 18 or frame 12 in accordance with this invention. As shown in FIGS. 1
 through 3A and most clearly in FIG. 3B, a pair of trailing disk assemblies
 20 and 22 are pivotably mounted to support portion 18 by a transverse
 shaft 24. As best shown in FIG. 3B, shaft 24 is mounted rotatably through
 flanges 26 of support portion 18. The respective ends of shaft 24 are
 mounted by bearings 28 within respective cylinders 30. Each cylinder is
 pinned or otherwise attached to a respective trailing disk assembly 20,
 22. More particularly, assembly 20 includes a trailing arm 32 that is
 welded at its forward end to right-hand cylinder 30; and assembly 22
 includes a similar trailing arm 34 that is likewise attached at its
 forward end to the left-hand cylinder.
 The opposite, distal end of each trailing arm carries one or more trailing
 disks. In particular, a first pair of trailing disks 36, 38 are mounted
 proximate the distal end of trailing arm 32. A second pair of trailing
 disks 40, 42 are similarly mounted proximate the distal end of trailing
 arm 34. In the version described herein, the trailing disks in each
 assembly are rotatably mounted by a respective shaft within a bearing
 housing carried at the end of the trailing arm. A first shaft 44 axially
 interconnects disks 36 and 38 and is itself rotatably mounted within a
 bearing housing 46 located proximate the distal end of trailing arm 32. A
 second shaft 48 likewise axially interconnects disks 40 and 42 and
 rotatably mounts those disks rotatably within a second bearing housing 50
 that is supported proximate the distal end of trailing arm 34. It should
 be noted that in alternative embodiments, the trailing disks may be
 fixedly attached proximate the distal ends of the trailing arms.
 Alternative numbers and arrangements of trailing disks and trailing disk
 arms may also be utilized. The particular construction of the trailing
 disk assemblies should be well known to persons skilled in the art and do
 not constitute a limitation of this invention. The trailing disks are
 typically orientated at a positive angle relative to the longitudinal axis
 of the bed. This means that the cutting edge of each trailing disk is
 disposed in a plane that is not parallel to the longitudinal axis of the
 bed. In the embodiment shown in FIGS. 1 through 4, this angle is set by
 providing the trailing arms with the curvature that is shown. In
 alternative embodiments, this curvature may be varied to provide other
 angles for the trailing disks. In still other versions, essentially
 straight trailing arms may be employed and other structure may be utilized
 to angle the trailing the disks relative to the longitudinal axis of the
 plow and the planting bed.
 Each of the trailing disk assemblies 20 and 22 is also interconnected to
 support portion 18 by a respective hydraulic or pneumatic relief
 mechanism. As shown in FIGS. 1 through 3B, a first relief mechanism 60 is
 interconnected between trailing arm 32 of assembly 20 and the right-hand
 side of support portion 18. A second relief mechanism 62 interconnects
 trailing arm 34 and the left-hand side of support portion 18. Mechanism 60
 includes a standard accumulator or other form of hydraulic or pneumatic
 piston. Various other types of resilient or shock absorption means may
 also be employed (e.g. mechanical spring means). One end of mechanism 60
 is interconnected to a bracket 64 carried by support portion 18. The other
 end of mechanism 60 is interconnected to a bracket 66 that extends
 upwardly from trailing arm 32. Similarly, relief mechanism 62 is operably
 interconnected between brackets 70 and 72 attached to support portion 18
 and trailing arm 34, respectively. Pivot pins 73 and 75, FIG. 3B, form the
 interconnection. Similar pins are used for the other relief mechanism 60.
 These relief mechanisms are pre-loaded or biased to urge the trailing
 disks 36, 38, 40 and 42 downwardly into engagement with the bed. When the
 trailing disks engage an obstruction, such as a stump or boulder in the
 bed, the hydraulic relief mechanisms 60 and 62 permit the disks and
 trailing arms to pivot upwardly so that the plow rides over the
 obstruction. When the obstruction is cleared, the trailing disk assembly
 is then urged downwardly by its respective relief mechanism 60, 62 to
 engage the disks with the bed.
 A critical and distinctive feature of this invention is the employment of a
 resiliently biased center-cut disk assembly 76, which is disposed between
 trailing arm disk assemblies 20 and 22. In the version shown in FIGS. 1
 through 3B, disk assembly 76 comprises an elongate center-cut arm 78 that
 is pivotably mounted at its upward end to support portion 18. This manner
 of attachment is described more fully below in connection with FIG. 4. The
 lower distal end of arm 78 carries a bearing housing 80. A single
 center-cut disk 82 is axially rotatably mounted to bearing housing 80. It
 should be understood that, in alternative embodiments, the center-cut disk
 assembly may employ fixed or non-rotating disks instead of the rotating
 disks shown herein. More particularly, disk 82 is axially mounted on a
 shaft 83 that is supported within bearing housing 76 in a conventional
 manner. Preferably, the disk is orientated at a positive angle (e.g. at
 least 1.degree.) relative to the longitudinal axis of the plow and the
 longitudinal axis of the bed being cultivated.
 As shown in FIG. 4, center-cut arm 78 has a hole 86 formed proximate its
 upward forward end. Hole 86 receives a mounting pin 88. A pair of washers
 90 are carried by pin 88 on respective sides of arm 78. These washers
 separate the center-cut arm from a pair of bushings or bearings 92
 likewise located on opposite sides of the center-cut arm. Bearings 92 are
 engaged with respective projections 94 of support portion 18. As a result,
 when the center-cut disk assembly 76 is installed within the plow, as
 shown in FIG. 5, the trailing arm 78 is pivotably mounted to pin 88
 between projections 94 of support portion of the frame. The center-cut arm
 and therefore the entire center-cut disk assembly, are capable of pivoting
 upwardly and downwardly, as indicated by doubleheaded arrow 96.
 Means are provided for resiliently biasing disk 82 of assembly 76 into
 engagement with the bed being plowed. Such means include a pneumatic or
 hydraulic relief mechanism 100, FIGS. 1 through 3B. Mechanism 100
 preferably comprises a pre-loaded nitrogen filled accumulator or similar
 apparatus. Alternative hydraulic, pneumatic or mechanical (e.g. spring
 loaded) shock absorbers and other resilient biasing means may also be
 employed. Mechanism 100 is interconnected between support portion 18 of
 frame 12 and center-cut arm 78 of assembly 76. Arm 78, FIGS. 4 and 5,
 includes a pair of mounting lobes 104 having aligned openings therein. The
 lower end (e.g. the piston rod) of relief mechanism 100 is engaged with
 aligned openings in lobes 104 and connected to the lobes by an appropriate
 pivot pin. As best shown in FIGS. 1 through 3B, the upper end of mechanism
 100 (e.g. the piston cylinder) carries its own pair of lobes 110 that are
 pivotably interconnected to a mounting arm or projection 112 attached to
 support portion 18.
 Mechanism 100 is preloaded with a desired biasing force that urges arm 78
 and therefore center-cut disk 82 downwardly to engage the planting bed
 with a corresponding degree of force. As a result, when the plow is pulled
 through the bed, a desired level of center-cutting is acheived. By the
 same token, when disk 82 of center-cut assembly 76 engages an obstruction
 such as a stump or boulder, mechanism 100 permits disk 82 and arm 78 to
 pivot upwardly about pin 88 (FIG. 4). The center-cut disk is therefore
 allowed to clear the obstruction quickly and cleanly without disrupting
 the entire plow. As soon as the obstruction is traversed, hydraulic
 mechanism 100 urges arm 78 and disk 82 back into plowing or tilling
 engagement with the forestry bed. The disk continues cultivating the bed
 with little or no disruption to the plow. An effective center-cut or
 precut is formed in the bed and improved seedling growth is achieved.
 Because the center-cut is formed so effectively, with few gaps or missed
 regions, the use of the resiliently biased center-cut disk assembly
 eliminates the need to perform multiple passes and/or the use of more
 complex machinery. Improved planting efficiency and cost savings are
 obtained. Similarly, the use of the resiliently biased center-cut disk
 assembly significantly reduces the need to use large horsepower tractors.
 Again, this improves cultivating and planting efficiency considerably.
 Center-cut disk 82 is disposed axially forwardly of trailing disks 36, 38,
 40 and 42. As a result, when the plow is operated the center disk assembly
 is pulled to precut the center of the bed while the trailing disks till
 the soil and form a mound over the precut center of the bed. This creates
 an improved cultivated bed that is particularly effective for achieving
 successful seedling growth.
 The improvements in cultivating a bed achieved by the center-cut disk
 assembly of this invention are further illustrated in FIGS. 7-10. In each
 view, the bed being cultivated is shown cross sectionally facing
 longitudinally in the direction of the bed. FIG. 7 schematically depicts
 two opposing pairs of prior art disks d that are arranged, in the manner
 described above, along respective sides of the plow. These disks d are
 pulled through the bed b so that the bed is cultivated in the manner shown
 in FIG. 8. Specifically, the disks d form a pair of spaced apart furrows f
 arranged longitudinally in bed b. Earth e from furrows f is pushed by
 disks d into a mound m that covers a center portion c of the bed. Center
 portion c remains uncut and is covered by loose earth e.
 In the present invention, FIG. 9, a center disk cd is positioned between
 opposing pairs of disks d such that the center disk cd intersects and
 interengages the longitudinal axis a of bed b. When the plow is pulled in
 the above described manner, center disk cd cuts bed b such that a center
 furrow cf is formed in the manner shown in FIG. 10. This center furrow is
 then covered with earth e by the trailing disks d that scoop earth out of
 furrows f and deposit it over center furrow cf. As shown in FIG. 10, the
 bed is cultivated much more effectively and improved forestry and planting
 results are achieved.
 Various number of disks may be employed in the center-cut disk assembly. As
 depicted in FIG. 6, alternative assembly 76a includes a pair of disks 82a
 and 82aa mounted rotatably on respective sides of center-cut arm 78a. A
 shaft 83a axially interconnects disks 82a and 82aa and rotatably mounts
 those disks to bearing housing 80a. The disks are again orientated such
 that they maintain a positive angle of at least 1.degree. with the
 longitudinal axis of the center-cut arm 78a, as well as the longitudinal
 axis of the plow and the bed being cultivated. In all other regards, disk
 assembly 76a is constructed and operates analogously to the single disk
 version previously described. A piston, accumulator or other hydraulic,
 pneumatic or mechanical relief means resiliently interconnect the disk
 assembly to the frame of the plow. The relief mechanism is omitted for
 clarity in FIG. 6 but it may comprise structure identical or analogous to
 the structure previously described. In still other versions, a virtually
 unlimited number of opposing center-cut disks may be employed.
 As illustrated in FIG. 1, bedding plow 10 may also include an optional
 wheel/packer apparatus 120. An alternatively configured wheel/packer
 apparatus 130 is shown in FIGS. 2 and 3. In either case, the wheel/packer
 apparatus includes an elongate frame 140 that is mounted to support frame
 12. A gas filled horizontally arranged accumulator 142 is interconnected
 between the forward end of frame 140 and a mounting assembly 144 carried
 by drawbar 14. A second, substantially vertical accumulator 146
 interconnects the forward end of frame 140 and support portion 18. Various
 other accumulator orientations (e.g. diagonal) may be also used.
 Accumulators 142 and 146 allow the wheel/packer assembly to again provide
 resilient bias to the wheel/packer apparatus. As a result, wheels 150,
 FIG. 1, and drums 160, FIG. 1, and 170, FIGS. 2 and 3, remain engaged with
 the bed under normal conditions but are permitted to retract upwardly and
 ride over obstructions when required. The hydraulic relief means again
 allow the bedding plow to operate stably under virtually all conditions.
 Disruption of the plow is avoided and improved plowing results are
 achieved. Again, it should be understood that the wheel/packer mechanisms
 shown in FIGS. 1 through 3 are optional features of the plow only and may
 be eliminated within the scope of this invention. Still other optional
 features may be connected to the frame in accordance with this invention.
 The various disk assemblies employed in plow 10 are constructed of durable
 and rugged material such as steel and other metals and metal alloys, which
 are commonly used in the plow industry and in related applications.
 Although specific features of the invention are shown in some of the
 drawings and not others, this is for convenience only, as each feature may
 be combined with any and all of the other features in accordance with this
 invention.
 Other embodiments will occur to those skilled in the art and are within the
 following claims: