Abstract:
A disc opener assembly and method, the assembly mounted to a tool support member connected to a work vehicle for opening a seed trench in the ground upon which the vehicle moves, the opener assembly including a disc member and at least some type of fastening member where the disc member includes a substantially flat circumferential portion, an intermediate portion and a recessed portion that forms a recess wherein, when the fastening member is used to secure the disc member to the support member, no part of the fastening member extends from the recess and the portion of the fastening member within the recess is accessible adjacent the intermediate member to facilitate fastening and unfastening.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   Not applicable. 
   STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
   Not applicable. 
   BACKGROUND OF THE INVENTION 
   This invention relates generally to agricultural planting equipment and more particularly to a disc opener assembly for a seed planter. 
   The efficient production of crops requires that seed be planted in various and selective manners that depend upon the type of seed, the soil conditions and the location. The seed planter must be capable of opening a seed trench at a selected depth, accurately spacing the seeds apart in the seed trench, covering the seed with an appropriate amount of soil and assuring that the seed is in proper contact with the soil. 
   To open seed trenches, a typical seed planter includes a plurality of disc openers mounted to an elongated frame. Each disc, as the label implies, includes an essentially flat round or circular member. In at least some cases, discs are mounted to axles which are in turn mounted to the frame for rotation about disc axis. Screws are typically used to mount the discs to the axles. 
   Existing seed planters utilize various adjustment mechanisms to control the depth of the seed trench. An exemplary adjustment mechanism includes gauge wheels, one wheel mounted adjacent each disc. Here, in at least some cases, in addition to setting disc depth, a gauge wheel may also help maintain an associated disc clean by forcing debris therefrom as the disc and wheel rotate. To accurately set disc depth and to effectively clean an associated disc, a gauge wheel should be mounted as close as possible to an adjacent disc surface. 
   Often at least a portion of a gauge wheel will be located immediately adjacent the screw heads that mount an associated disc to an axle. To enable gauge wheels to be as close as possible to the disc surfaces, the heads of the screws that mount the discs to the axles can be countersunk so that surfaces thereof are flush with the surfaces of the discs that face the wheels. Over time the opening discs wear appreciably and eventually have to be replaced or sharpened. The discs can be removed by using a screwdriver to unscrew the screws that secure the discs to the axles. 
   Unfortunately, often the force required to unscrew a disc is relatively large. As generally known, the torque that can be applied using a screwdriver is limited. In addition, as well known, if a screwdriver head is not properly seated within a head receiving recess, the head can slip out of the recess during a loosening motion and the screw head can be stripped or at least partially stripped which further reduces the torque that can be applied to the screw during a next attempt to loosen, In many cases it has been observed that, because of the proximity of the screw heads to field debris and soil, the head receiving recesses in the screws become caked with matter which, if not removed, blocks proper screwdriver head seating. 
   Thus, it would be advantageous to have a disc-gauge wheel assembly where the components that secure a disc to an axle are easy to manipulate and where the components allow positioning of the gauge wheel immediately adjacent a surface of the disc. 
   BRIEF SUMMARY OF THE INVENTION 
   One embodiment of the presenting invention includes a disc opener assembly mounted to a tool support member connected to a work vehicle for opening a seed trench in the ground upon which the vehicle moves, the opener assembly comprising a disc member including a circumferential portion and a central portion, the circumferential portion including a flat doughnut shaped circumferential wall member having first and second oppositely facing and substantially parallel surfaces, the central portion including a recessed wall member and an intermediate linking member, the recessed wall member forming first and second oppositely facing and substantially parallel surfaces where the first surface of the recessed wall member faces in the same direction as the first surface of the circumferential wall member, the recessed wall member recessed so that the first surface of the recessed wall member is offset from the first surface of the circumferential wall member to form a recess, the intermediate linking member linking the recessed wall member to the circumferential wall member, the recessed wall member forming at least a first through hole and at least a first fastening member including a base member and an extending member, the extending member extending from the base member through the through hole and secured at a distal end to the support member, the base member restraining the recessed wall member to hold the disc member to the support member with the base member completely within the recess, wherein, the base member and the recessed wall member are dimensioned such that a gap is formed between the base member and the intermediate linking member when the base member restrains the recessed wall member. 
   In at least some cases the first fastening member includes a bolt and wherein the base member and the extending member are a bolt head and a threaded shaft, respectively, the head including a circumferential surface and oppositely facing first and second end surfaces, the shaft extending from the second end surface and received at least partially by the support member to secure the disc member to the supporting assembly with the head member located completely within the recess. In some cases the gap is at least one sixteenth of an inch. In some cases the gap is at least one half an inch. 
   Some embodiments further including second, third and fourth bolts, each of the bolts includes a head member and a shaft, the shafts of the second, third and fourth bolts passing through the second, third and fourth through holes and at least partially received by the supporting assembly to mount the disc opener assembly to the support member, respectively, with the head members of the second, third and fourth bolts completely within the recess and, wherein, a gap exists between the circumferential surface of each of the head members of the second, third and fourth bolts and the intermediate linking member and a gap also exists between each of the first, second, third and fourth head members. In some cases the gaps are at least one sixteenth of an inch. In some embodiments each of the gaps are at least one half an inch. 
   In at least some embodiments the bolt is secured to the supporting assembly via a nut. In some cases the circumferential surface of the bolt head is hexagonal. 
   In some cases the intermediate linking member is an intermediate wall member. In some embodiments intermediate wall member is frusto-conical in shape. In some cases the intermediate wall member diverges at an angle from the conical wall member toward the recessed wall member at an angle of between 20 degrees and 75 degrees. In some cases the intermediate wall member diverges at an angle from the conical wall member toward the recessed wall member at an angle of substantially 45 degrees. 
   Some embodiments further include a gauge wheel supported adjacent and substantially flat up against at least a portion of the first surface of the circumferential wall member. In some cases the second surface of the recessed wall member is adjacent the support member. 
   Some embodiments include a disc opener assembly mounted to a tool support member connected to a work vehicle for opening a seed trench in the ground upon which the vehicle moves, the opener assembly comprising a disc member including a circumferential portion and a central portion, the circumferential portion including a flat doughnut shaped circumferential wall member having first and second oppositely facing and substantially parallel surfaces, the central portion including a recessed wall member and an intermediate frusto-conical linking wall member, the recessed wall member forming first and second oppositely facing and substantially parallel surfaces where the first surface of the recessed wall member faces in the same direction as the first surface of the circumferential wall member, the recessed wall member recessed so that the first surface of the recessed wall member is offset from the first surface of the circumferential wall member to form a recess, the intermediate linking wall member linking the recessed wall member to the circumferential wall member, the recessed wall member forming at least first and second through holes and at least first and second bolts, each of the bolts including a bolt head and a threaded shaft, each head including a circumferential surface and oppositely facing first and second end surfaces, the first and second shafts extending from the second end surfaces of the first and second bolt heads, through the first and second through holes and at least partially received by the supporting assembly, respectively, to secure the disc member to the supporting assembly with the head members located completely within the recess and with the second surface of the recessed wall member adjacent the support member wherein, the heads and the recessed wall member are dimensioned such that gaps of at least ¼th of an inch are formed between the heads and the intermediate wall member and between the first and second heads when the bolts secure the disc member to the supporting assembly. 
   In some cases the recessed wall member forms third and fourth through holes, the assembly further including third and fourth bolts that include heads and shafts where the third and fourth shafts extend through the third and fourth through holes with distal ends secured to the support member. Some cases further include a gauge wheel supported adjacent and substantially flat up against at least a portion of the first surface of the circumferential wall member. 
   Some embodiments include a method for opening a seed trench in the ground upon which a vehicle moves where a support member is supported by the vehicle, the method comprising the steps of providing a disc member that includes a circumferential portion and a central portion, the circumferential portion including a flat doughnut shaped circumferential wall member having first and second oppositely facing and substantially parallel surfaces, the central portion including a recessed wall member and an intermediate linking member, the recessed wall member forming first and second oppositely facing and substantially parallel surfaces where the first surface of the recessed wall member faces in the same direction as the first surface of the circumferential wall member, the recessed wall member recessed so that the first surface of the recessed wall member is offset from the first surface of the circumferential wall member to form a recess, the intermediate linking member linking the recessed wall member to the circumferential wall member, the recessed wall member forming at least a first through hole, mounting the disc member to the support member using at least a first bolt that includes a bolt head and a threaded shaft, the head including a circumferential surface and oppositely facing first and second end surfaces, the shaft extending from the second end surface of the bolt head, through the through hole and at least partially received by the supporting assembly to secure the disc member to the supporting assembly with the head member located completely within the recess, wherein, the head and the recessed wall member are dimensioned such that gaps of at least ¼th of an inch are formed between the head and the intermediate wall member. 
   In some cases the step of providing a disc member includes providing a disc member where the recessed wall member forms a plurality of through holes and wherein the step of mounting includes using a plurality of bolts to mount the disc member to the support member wherein the bolt heads are each completely within the recess and wherein gaps exist between each of the circumferential surfaces of the bolt heads and the intermediate wall member and between adjacent bolt heads. 
   These and other aspects of the invention will become apparent from the following description. In the description, reference is made to the accompanying drawings which form a part hereof, and in which there is shown a preferred embodiment of the invention. Such embodiment does not necessarily represent the full scope of the invention and reference is made therefore, to the claims herein for interpreting the scope of the invention. 

   
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       FIG. 1  is a side elevational view of a disc opener assembly mounted on a tool bar coupled to a work vehicle; 
       FIG. 2  is a perspective view from the rear of one of the disc opener assemblies shown in  FIG. 1 ; 
       FIG. 3  is a front plan view of the disc member of  FIG. 2 ; 
       FIG. 4  is an exploded view showing an exemplary disc member and associated components for mounting the disc member according to at least one inventive embodiment; 
       FIG. 5  is an exploded view showing the disc member of  FIG. 4  and additional detail; and 
       FIG. 6  is a partial cross-sectional view of the disc member and associated components of  FIG. 4 , albeit where the components are secured together. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Referring now to the drawings wherein like reference numerals correspond to similar elements throughout the several view and, more specifically, referring to  FIG. 1 , the present invention will be described in the context of an exemplary work vehicle  5  having a vehicle support structure  4  to which a plurality of wheels  3  are rotatably mounted. Although a four wheel work vehicle is illustrated, it should be understood that a 6 or 8 wheel vehicle is contemplated as well as a tracked vehicle, with the tracks being supported by wheels. A work vehicle  5  typically has a power source coupled to a transmission with the transmission operatively coupled to at least two of the wheels  3 . The power source can be an internal combustion engine such as a gasoline engine or a diesel engine and it may also be an electric motor or a steam driven turbine. The present disc opener assembly for a seed planter is for a single disc opener arrangement. 
   Referring still to  FIG. 1  and also to  FIGS. 2 and 5 , a disc opener assembly  10  is mounted on a tool bar  7  connected to work vehicle  5  for opening a seed trench  8  in the ground upon which vehicle  5  moves. A main arm  12  is attached to tool bar  7  with a disc  14  mounted for rotation on the main arm  12 . A depth adjustment mechanism  40  is used to adjust the depth of the disc  14  in the seed trench  8  with a seed placement device (not labeled) positioned in the seed trench  8  for depositing a seed  71  in the seed trench  8 . The seed trench  8  is opened by disc  14  as work vehicle  5  moves across the ground. 
   The disc opener assembly  10  is provided with a disc scraper  30  mounted on a scraper mount  33  attached below the main arm  12  and aligned with the disc  14  to clean the disc. Disc scraper  30  is a planar member with at least one edge  32  which is aligned with the disc  14  and contacts the disc to clean dirt and plant debris from the disc  14  as the disc is rotated. The disc scraper  30  is attached to the scraper mount  33  by fasteners or other convenient and conventional means of mounting. In the illustrated embodiment, two retainers  36  and other components that are not illustrated, bias scraper  30  into a position in which the scraper self-aligns with disc  14 . 
   Disc opener assembly  10  includes a packer wheel  16  rotatably mounted on an axle  18  with the axle  18  slidingly installed in a position tube  20 . The position tube  20  is attached to a packer wheel arm  19  connected to main arm  12 . As the disc opener assembly  10  moves through the field opening a seed trench  8 , the packer wheel  16  closes the seed trench  8 . The distance of the packer wheel  16  away from the seed trench  8  determines the amount of soil deposited into the seed trench  8  during the closing operation and the compaction of the soil on the seed  71  in the trench. 
   Referring to  FIGS. 2 ,  5  and  6 , assembly  10  has a depth adjustment mechanism  40 . To this end, gauge wheel  46  is mounted for rotation on one end  43  of a gauge wheel arm  44  with an opposite end  45  of the gauge wheel arm  44  being attached to a gauge wheel pivot  48 . The gauge wheel  46  can be made from composite elements, such as a tire rim formed from metal or plastic, connected by a suitable fastener and having a semi-pneumatic tire disposed about its periphery. The semi-pneumatic tire helps reduce side-wall compaction of the seed trench  8  while allowing the gauge wheel  46  to move toward and away from the ground as the depth adjustment mechanism  40  is operated, thereby adjusting the depth of the disc  14 . Operation of the depth adjustment mechanism is described in greater detail in U.S. Pat. No. 6,386,127 which is titled “Disc Opener Assembly For A Seed Planter” and which is incorporated herein by reference for its teachings regarding depth adjustment. 
   Referring now to  FIGS. 2 ,  4 ,  5  and  6 , assembly  10  includes a separate axil  60  for each of the disc openers supported thereby. Hereinafter, axil  60  is also referred to as support member generally. As best illustrated in  FIG. 5 , axil  60  includes, among other components, a base plate member  64  and an alignment extension member  62 . Plate member  64  is a circular flat and rigid member that includes a bearing surface  66  that forms four through holes, two of which are collectively identified by numeral  68  in  FIG. 5 , that are equispaced around the circumference of plate member  64  (only three through holes  68  illustrated in  FIG. 5 ). Extension member  62  extends perpendicular to bearing surface  66  and is centered between through holes  68 . 
   Referring to  FIGS. 3  though  6 , exemplary disc member  14  includes a circumferential portion  70  and a central portion  72 . Circumferential portion  70  is a donut shaped substantially flat member that has a circular circumferential edge  74  and that forms first and second oppositely facing and generally parallel surfaces  76  and  78 , respectively. 
   Central portion  72  includes an intermediate linking member or wall member  80  and a recessed wall member  82 . Recessed wall member  82  is a circular and substantially flat member having first and second oppositely facing surfaces  84  and  86 , respectively. First surface  84  of recessed member  82  is offset or recessed from first surface  76  of circumferential member  70  so as to form a central recess  90 . Intermediate wall member or linking member  80  links recessed member  82  to circumferential member  70 . In at least some embodiments, as illustrated, intermediate wall member  80  is frusto-conical in shape and, to that end, diverges from circumferential member  70  to recessed member  82  forming an angle α with circumferential member  70  of between 20 and 75 degrees, and in at least some embodiments, forming an angle α of approximately 45 degrees. 
   Referring still to  FIGS. 3–5 , recessed wall member  82  forms a central opening  92  and four through holes, two of which are collectively identified by numeral  94  in each of  FIGS. 4 and 5 . As the label implies, central opening  92  is formed at the center of disc member  14 . Through holes  94  are equispaced about opening  92  and are arranged so that they align with the openings  68  formed by plate member  64  when extension member  62  is received within opening  92 . 
   Referring again to  FIG. 4  and also to  FIG. 6 , in the illustrated embodiment, four bolts, two of which are collectively identified by numeral  98  in each of  FIGS. 4 and 6 , are provided for mounting disc member  14  to axil  60 . As shown in  FIG. 4 , an exemplary bolt  98  includes a head member  100  and a threaded shaft  102 . Head  100  includes first and second oppositely facing surfaces  104  and  106  and a circumferential surface  108  that traverses the distance between the first and second surfaces  104  and  106 . In the illustrated embodiment, circumferential surface  108  is hexagonal (see end view of bolt  98  in  FIG. 3 ). Shaft  102  extends perpendicular to and from second surface  106  to a distal end  112 . A separate nut  114  (see  FIG. 4 ) is provided for each of the bolts  98 . 
   As best shown in  FIG. 6 , the dimensions of the bolt heads  100  are much smaller than the dimensions of recessed wall member  82  such that, when the heads  100  are located within recess  90 , gaps g exist between the circumferential surfaces (e.g.,  108 ) of the heads  100  and the intermediate linking wall member  80  and also exist between adjacent heads  100 . 
   To mount disc member  14  to axil  60 , extending member  62  is aligned with opening  92  and slid therethrough until second surface  86  of recessed wall member  82  abuts bearing surface  66  of plate member  64 , disc member  14  is rotated until through holes  94  are aligned with openings  68  formed by plate member  64 . Next, bolt shafts  102  are slid through the aligned through holes  94  and opening  66  and nuts  114  are tightened on to the distal ends  112  of the bolt shafts  102 . Here, to tighten the bolts and associated nuts, wrenches or the like can be used to grasp the bolt heads  100  and nuts  114 . Importantly, gaps g (see again  FIG. 6 ) enable a person installing disc member  14  to easily grasp the heads  100  and apply relatively large torquing forces thereto. Similarly, to remove a disc member  14 , a wrench or other type of tool can be used to grasp the bolt heads  100  using a wrench or the like and can apply large force thereto. 
   Referring still to  FIGS. 4–6 , gauge wheel  46  is mounted to gauge wheel arm  44 . As shown best in  FIG. 6 , in at least some embodiments, gauge wheel  46  can be mounted extremely close to front surface  76  of disc member  14 . As shown because the heads of bolts  98  are completely located within recess  90 , the heads do not obstruct placement or rotation of gauge wheel  46 . 
   One or more specific embodiments of the present invention have been described above. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developer&#39;s specific goals, such as compliance with system-related and business related constraints, which may vary from one implementation to another. Moreover, it should be appreciated that such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure. 
   Thus, the invention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the following appended claims. To apprise the public of the scope of this invention, the following claims are made: