Abstract:
A disc opener assembly connected to a tool bar linked to a vehicle for movement over the ground for opening a seed trench therein, the assembly comprising a main arm member attached to the tool bar, a disc mounted for rotation on the main arm, a gauge arm member having proximal and distal ends, the proximal end mounted for pivotal motion about a pivot axis to the main arm member, a gauge wheel mounted to the distal end of the gauge arm member, a first coupler mounted to the main arm member, a second coupler linked to the gauge arm member and juxtaposed proximate and for movement with respect to the first coupler along a coupling axis that is substantially parallel to the pivot axis, the second coupler configured to engage the first coupler when biased there against and a retainer for maintaining the first and second couplers engaged.

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. 
   This section of this document is intended to introduce various aspects of art that may be related to various aspects of the present invention described and/or claimed below. This section provides background information to facilitate a better understanding of the various aspects of the present invention. It should be understood that the statements in this section of this document are to be read in this light, and not as admissions of prior art. 
   Efficient crop growth requires that seed be planted in different manners that depend at least in part upon soil conditions, fertilizer employed, seed type and anticipated weather and sun exposure conditions. To this end, a seed planter trench opener disc must be capable of opening a seed trench to a selected depth and accurately placing seeds therein to assure that the seed is in proper contact with the soil. 
   Existing seed planters include various types of depth adjusting mechanisms to control trench depth. One particularly useful type of depth adjusting mechanism provides gauge wheels that, when in a depth adjusting position, have a bottom wheel surface that generally resides proximate and vertically above the bottom disc edge of an associated trenching opener disc. Here, the wheel travels along a field surface and therefore limits disc depth into the soil. In many cases a plurality of disc openers are each independently mounted to a support bar for towing behind a tractor or the like and a separate gauge wheel is mounted to each of the disc openers via an adjustable linkage mechanism so that the vertical height difference (hereinafter “the surface-edge difference”) between the bottom wheel surface and the bottom disc edge is adjustable. For instance, an exemplary disc-wheel configuration may be adjustable so that the surface-edge difference can be set to between one and five inches. 
   Unfortunately, most depth control mechanisms of the type described above have one or more shortcomings. For instance, some depth control mechanisms of the above type have poorly located depth adjustments that make it difficult for an operator to access the adjusting mechanism. Some adjusting mechanisms require an operator to use two hands to adjust disc depth and to assume awkward positions when performing adjustments. Other adjusting mechanisms utilize a threaded shaft which takes a large amount of time to adjust and which has a tendency to seize up due to rust or become bound up due to accumulation of field debris. Still other adjusting mechanisms utilize one or a plurality of nut and bolt pairs to facilitate adjustment—these mechanisms often require two hands and are time consuming to manipulate. Moreover, many mechanisms require a large number of complex components that require small tolerances, are relatively expensive to manufacture and assemble and are expensive to maintain and replace when damaged. Furthermore, some mechanisms are difficult to manipulate as the mechanical advantage afforded by the mechanism designs is less than optimal. In addition, at least some prior mechanisms have increased the width of an associated seeding row unit disadvantageously. 
   Thus, it would be advantageous to have a seed planter disc opener assembly that provides a conveniently located depth control mechanism, that is operable via one hand, that requires minimal, simple and robust components and that is inexpensive to manufacture, assemble and maintain. 
   BRIEF SUMMARY OF THE INVENTION 
   Certain aspects commensurate in scope with the originally claimed invention are set forth below. It should be understood that these aspects are presented merely to provide the reader with a brief summary of certain forms the invention might take and that these aspects are not intended to limit the scope of the invention. Indeed, the invention may encompass a variety of aspects that may not be set forth below. 
   It has been recognized that the shortcomings described above with respect to the known prior art can be overcome by providing a simple cooperating coupler configuration where a moveable coupler moves along a coupling axis to engage and disengage another coupler and where the coupling axis is substantially parallel to a pivot axis of a gauge arm to which a gauge wheel is mounted. In some cases it has also been recognized that a handle member can be provided as a mounting base for the moveable coupler where the handle provides a relatively large mechanical advantage when manipulating the moveable coupler. Here, where the mechanical advantage is appreciable, in at least some cases, the force of a biasing member that biases the moveable coupler toward the other coupler may be increased to provide a more robust design. In addition, in at least some cases, the distance over which a disengaging action may occur can be greater than the distances facilitated by other depth control solutions and therefore the margin for manufacturing error can be increased appreciably and overall costs can be reduced. 
   Consistent with the above comments, at least some embodiments of the invention include a disc opener assembly connected to a tool bar linked to a vehicle for movement over the ground for opening a seed trench therein, the assembly comprising a main arm member attached to the tool bar, a disc mounted for rotation on the main arm, a gauge arm member having proximal and distal ends, the proximal end mounted for pivotal motion about a pivot axis to the main arm member, a gauge wheel mounted to the distal end of the gauge arm member, a first coupler mounted to one of the main arm member and the gauge arm member, a second coupler linked to one of the main arm member and the gauge arm member and juxtaposed proximate and for movement with respect to the first coupler along a coupling axis that is substantially parallel to the pivot axis, the second coupler configured to engage the first coupler when biased there against and a retainer for maintaining the first and second couplers engaged. 
   In at least some embodiments the first coupler is mounted to the main arm member and the second coupler is linked to the gauge arm member. The retainer or retainer member may be a biasing member or, in some cases, may be a mechanical latching assembly of some type. 
   In some cases a limit member may be rigidly mounted to and extending from the gauge arm member, the biasing member positioned between the limit member and the second coupler. Here, in some cases, the gauge arm member will form the limit member (i.e., the limit member will be an extension of the gauge arm member. 
   Some other embodiments of the invention include a disc opener assembly connected to a tool bar for movement over the ground for opening a trench therein, the assembly comprising a main arm member attached to the tool bar, a disc mounted for rotation on the main arm, a gauge arm member having proximal and distal ends, the proximal end mounted for pivotal motion about a pivot axis to the main arm member, a gauge wheel mounted to the distal end of the gauge arm member, a first coupler mounted to the main arm member, a second coupler linked to the gauge arm member and juxtaposed proximate and for movement with respect to the first coupler along a coupling axis that is substantially parallel to the pivot axis, the second coupler configured to engage the first coupler when biased there against, a biasing member mounted between the gauge arm member and the second coupler for biasing the second coupler toward the first coupler and a handle extending from the second coupler for moving the second coupler away from the first coupler to disengage the first and second couplers. 
   These and other objects, advantages and 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 
     The invention will hereafter be described with reference to the accompanying drawings, wherein like reference numerals denote like elements, and: 
       FIG. 1  is a perspective view of a tractor and a seed planting and depth control assembly according to at least one embodiment of the present invention; 
       FIG. 2  is a perspective view of depth control assembly of  FIG. 1 ; 
       FIG. 3  is a perspective view of a gauge arm member and handle member sub-assembly of  FIG. 2 ; 
       FIG. 4  is a partial plan view of the components of  FIG. 3 ; 
       FIG. 5  is a partial cross-sectional view of the components of  FIG. 4 ; 
       FIG. 6  is a partial perspective view of a gauge wheel mounting member shown in  FIGS. 2 and 3 ; 
       FIG. 7  is a partial plan view of one of the couplers shown in  FIG. 5 ; 
       FIG. 8  is similar to  FIG. 3 , albeit illustrating another embodiment of the present invention; and 
       FIG. 9  is similar to  FIG. 5 , albeit illustrating an embodiment of the present invention that does not include a biasing member but, instead, includes a retainer in the form of a latch assembly. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   One or more specific embodiments of the present invention will be described below. 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 developers&#39; 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. 
   Referring now to the drawings and, more specifically, referring to  FIG. 1 , the present invention will be described in the context of an exemplary agricultural tractor  5  including an agricultural implement attached to a rear end  6  thereof. The implement generally includes a tool bar  7 , at least one seed bin  74  and at least one seed planter assembly  10 . Tool bar  7  is generally an elongated rigid bar that extends perpendicular to the direction of tractor travel. Bin or Bins  74  are generally mounted above bar  74  while assembly or assemblies  10  are mounted below bar  7  when in an operating position and may be pivoted up into a position generally above bar  7  when in a stowed position for transport or the like. When in the operating position illustrated in  FIG. 1 , an opening or trenching disc  14  cuts a trench in the ground over which tractor  12  travels as disc is pulled through a field. A gauge wheel  46  rides over the soil there below and limits trench depth as described in greater detail below. The present invention relates to the depth setting mechanism associated with wheel  46 . 
   Herein, while the implement mounted to the rear of tractor  5  may include a plurality of bins  74  and assemblies  10  spaced apart along bar  7  as well known in the art, each of the assemblies and bins would be similarly constructed and operate in a similar fashion and therefore only one of assemblies  10  will be described here in any detail. In addition, it should be recognized that seed planter assemblies  10  like the assemblies described herein may also be used on other types of seeding implements such as larger implements that may be pulled behind a tractor and be supported by separate implement support wheels like a wagon. 
   Referring now to  FIGS. 2 through 7 , an exemplary assembly  10  is illustrated in greater detail and includes, generally, a main arm member  12 , a gauge a gauge arm member  16 , a main arm member extension  17 , a disc scraper  18 , a seed tube  20 , a handle member  24 , a first coupler  26 , a second coupler  22  and a biasing member  40 . Construction and general operation of disc  14 , seed tube  20  and gauge wheel  46  are well known in the art and therefore will not be described here in detail. Here, with respect to gauge wheel  46 , it should suffice to say that wheel  46  may 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 is operated. 
   With respect to disc scraper  18 , here it should suffice to say that scraper  18  is mounted on a scraper mount (not illustrated) attached below main arm member  12  and is aligned with the disc  14  to clean disc  14 . Scraper  18  is a planar member with at least one edge  32  that is aligned with the disc  14  and contacts the disc to clean dirt and plant debris from disc  14  as the disc is rotated. The disc scraper  18  is attached to the scraper mount by fasteners or other convenient and conventional means of mounting. Scraper  18  typically is made from steel which has been treated to have a high surface hardness which increases wear resistance. 
   With respect to seed tube  20 , it should suffice to say that tube  20  is a hollow cylindrical member that in linked to the interior of seed receptacle  74  (see  FIG. 1 ) for receiving metered seed from receptacle  74  and depositing the seed into a seed trench formed by disc  14 . A deflector tab  79  is mounted to the lower end of seed tube  20 . If seed rebounds or deflects from a seed trench  8  there below, the deflector tab  79  redirects the seed back towards the seed trench  8 . 
   Referring now to  FIGS. 1 and 2 , main arm member  12  includes proximal and distal ends  34  and  36 , respectively, the proximal end  34  mounted to tool bar  7  (see again  FIG. 1 ) and the distal end  36  extending generally down and rearward therefrom. Distal end  36  forms two substantially horizontal openings (not labeled) that are used to mount many of the other assembly  10  components. For example, main arm extension  17  is mounted to distal end  36  via the openings and suitable mechanical fasteners (e.g., bolts). In addition, opening disc  14  is rotatably mounted via a forward one of the openings in a fashion well known in the art. As illustrated disc  14  is centrally mounted to the distal end  36  of arm member  12  for rotation along an axis generally perpendicular to the direction of tractor travel. Moreover, gauge arm member  16  is pivotally mounted to a rearward one of the openings. Hereinafter the axis about which the second or rearward opening is formed is referred to as a gauge wheel pivot axis or simply as a pivot axis  69 . In at least some embodiments main arm member  12  and extension  17  may be integrally formed such that a first coupler  32  can be said to be located at the distal end of the main arm member. 
   Referring still to  FIG. 2 , when main arm extension  17  is mounted to the distal end of arm member  12 , extension  17  extends generally rearward therefrom and, at a distal end  48 , extends upward to a first coupler  26 . Referring also to  FIG. 7 , first coupler  26  is a rigid member including a coupler surface  29  that forms a plurality of teeth or other suitably formed keyed recesses, three of which are collectively identified by numeral  50 . In at least some embodiments the teeth are formed in a uniform pattern wherein they generally extend along trajectories that fan out about a central point as illustrated in FIG.  7 . 
   Referring now to  FIGS. 3 through 6 , gauge arm member  16  is generally a rigid, substantially planar member that has a shape for supporting other components that extend therefrom. In some embodiments member  16  may have some non-planar shape to facilitate unobstructed linkage and relative movement with respect to other assembly  10  components. Member  16  will be described primarily in the context of its orientation in  FIG. 3  wherein relative juxtapositions of components are indicated via terms such as below, above, left and right in FIG.  3 . 
   Referring to  FIG. 3 , a pivot post  56  extends substantially perpendicular to member  16  from a lower left hand corner thereof. The lower left hand corner is also referred to herein as the proximal end  21  of member  16  as end  21  is mounted to main arm member  12 . The end of member  16  opposite proximal end  21  is referred to herein as the distal end  19 . A distal end of post  56  forms an opening  57  for receiving a pin  28  to mount and secure post  56  within the second opening formed at the distal end of main arm member  12  (see again FIG.  2 ). 
   Referring to  FIGS. 3 through 5 , two mounting member collectively identified by numeral  58  are welded or otherwise integrally secured to member  16  on the same side from which post  56  extends. Members  58  are secured to member  16  approximately midway between the left and right most edges of member  16  and proximate a lower edge of member  16  and are spaced apart so as to form a space for receiving a cylindrically shaped proximal end of handle member  24  therebetween in a lengthwise fashion. In addition, each of members  58  forms an opening  76  (only one illustrated) where the openings  76  are formed about a rotation axis  68  and are aligned to receive a bolt or other suitable mechanical fastener therethrough. Rotation axis  68  is perpendicular to pivot axis  69  as best seen in FIG.  3 . 
   Two guide members collectively identified by numeral  60  are welded or otherwise rigidly secured to and extend form the same side of gauge arm member  16  as post  56 . Guide members  60  are positioned above members  58  and such that they form a space therebetween for receiving the shaft of handle member  24 . In at least some embodiments the facing surfaces of members  60  may slope toward each other proximate the surface of member  16  so that when the handle shaft is rotated to a position therebetween the shaft is snuggly received therebetween. Here, the surface of gauge arm member  16  and, in some cases, guide members  60 , form a limit surface or operate as a limit member for limiting the extent of handle member  24  rotation about axis  68 . 
   Referring to  FIGS. 1 ,  2 ,  3  and  6 , a gauge arm extension  62  extends from the distal end  19  of gauge arm member  16  and includes two sub-members. A first sub-member  64  extends perpendicular to member  16  and in a direction opposite the direction in which post  56  extends. A second sub-member  66  extends from a distal end of member  64 , substantially parallel to member  64  and generally in the direction of tractor travel (i.e., generally to the right in FIG.  3 ). As seen in  FIG. 6 , an opening  78  is formed in second sub-member  66 . Gauge wheel  46  is mounted for rotation via a suitable mechanical fastener to opening  78 . 
   Referring to  FIG. 5 , gauge member  16  forms a recess  80  between members  58  and guide members  60  that, when the proximal end of handle member  24  is mounted between members  58 , is aligned with a portion of the shaft of handle member  24  as illustrated. Recess  80  is dimensioned to receive one end of the biasing member or, in the illustrated example, spring  40  therein. In addition, in at least some cases, to help retain a spring within recess  80 , a post  82  may be centrally formed within recess  80  so that the end of the spring  40  received within recess  80  is juxtaposed between facing surfaces of the post  82  and recess  80 . 
   Referring to  FIGS. 1 through 5 , handle member  24  is a rigid elongated member having opposite distal and proximal ends  84  and  86 , respectively. Handle member  24  may be many different lengths but, preferably, is long enough that the distal end thereof extends above other assembly  10  components. In at least some embodiments handle  24  will be longer that a foot long. A cylindrical mounting member  70  is provided at proximal end  86 . Member  70  has a length dimension (not labeled) that fits within the space defined by the facing surfaces of mounting members  58  and forms an opening (not illustrated) having a radius that is similar to the radius of the openings  76  formed by members  58 . To mount handle  24  to gauge arm member  16 , mounting member  70  is placed between the facing surfaces of members  58  such that the openings formed thereby are aligned with rotation axis  68 . Thereafter a bolt or other suitable mechanical fastener is used to secure the mounting members  70  and  58  such that member  70  can rotate about axis  68 . 
   Referring still to  FIGS. 1 through 5 , second coupler  22  has a generally block shaped form and is welded or otherwise rigidly secured on one side to the shaft of handle member  24  approximately midway along the length of member  24  and, in at least the illustrated embodiment, between mounting members  58  and guide members  60  when handle member  24  is secured to gauge member  16  as described above. Second coupler  22  includes a coupling surface  90  that, like surface  29 , forms a plurality of teeth  92  (only three collectively labeled) that extend along trajectories that fan out about a central axis (not labeled) in a fashion similar to that of teeth  50 . The pattern of teeth  92  is a mirror image of teeth  50  formed by surface  29  (see again  FIG. 7 ) so that teeth  92  and teeth  50  mesh together. Other surface configurations are contemplated that facilitate rigid coupling of couplers  22  and  26 . For example, in at least some embodiments one of surfaces  29  or  90  may form a single tooth that is receivable between two of the teeth formed on the other of the couplers to secure relative positions. In other embodiments the teeth may be replaced by relatively smooth recesses and ribs that cooperate to maintain relative positions when in contact. 
   Importantly, the coupling surfaces  29  and  90  have to be able to couple when gauge arm member  16  and handle ember  24  are in any of several different positions. Thus, for instance, referring to  FIGS. 3 and 7 , during a first seeding operation member  16  and associated second coupler  22  may be positioned such that second coupler surface  90  engages only the portion of first coupler surface  29  including teeth  50   a . Similarly, during a second seeding operation member  16  and associated second coupler  22  may be positioned such that second coupler surface  90  engages only the portion of first coupler surface  29  including teeth  50   b . During other seeding operations other relative juxtapositions of coupler surfaces  29  and  90  are contemplated for altering trenching depth. Thus, in the illustrated example the central axis from which the trajectories of teeth  50  and  92  fan out should be a common axis to ensure accurate registration of teeth  50  and  92  for coupling purposes. 
   Referring to  FIG. 5 , a post member  98  extends from the surface of the shaft of handle member  24  opposite second coupler  22 . post member  98  has dimensions similar to post member  82  that extends from within recess  80  such that the second end of spring member  40  is receivable thereon for support and guidance. 
   Biasing spring  40  is generally a helical spring member. Spring  40  has a length dimension such that spring  40  is partially loaded when compressed between the facing surfaces of recess  80  and the shaft of handle member  24  with the first and second couplers  26  and  22 , respectively, engaged. Thus, spring member  40  biases the couplers into engagement. 
   Referring now to  FIGS. 1 through 5  and  7 , it should be appreciated that the depth of a trench formed by disc  14  as assembly  10  is pulled through a field is easily adjustable via manipulation of handle member  24 . To this end, the relative vertical positions of the lower edges of disc  14  and gauge wheel  46  are adjustable by rotating handle member  24  in a clockwise direction about axis  68  as indicated by arrow  100  in FIG.  5  and against the force of biasing spring  40  so that coupler  22  becomes decoupled from coupler  26 , rotating handle member  24  and associated gauge arm member  16  about pivot axis  69  (see also  FIG. 4 ) to a different position and then rotating handle member  24  in a counter-clockwise direction about axis  68  as indicated by arrow  102  in FIG.  5  and with the force of biasing spring  40  so that coupler  22  becomes re-coupled to coupler  26 . Referring also to  FIG. 4 , when handle member  24  and gauge arm member  16  are rotated in a clockwise direction as indicated by arrow  104  in  FIG. 4 , distal end  19  of gauge arm member  16  also rotates clockwise as indicated by arrow  106  and hence gauge wheel  46  is lowered and the trench depth is reduced. Similarly, when handle member  24  and gauge arm member  16  are rotated in a counter-clockwise direction as indicated by arrow  108  in  FIG. 4 , distal end  19  of gauge arm member  16  also rotates counter-clockwise as indicated by arrow  110  and hence gauge wheel  46  is raised and the trench depth is increased. 
   Referring to  FIGS. 2 through 5 , when handle member  24  is rotated about rotation axis  68  and such that second coupler  22  disengaged first coupler  26 , the shaft of handle member  24  is received between guide members  60  and is supported there between to reduce the force applied to members  58  during pivoting action about pivot axis  69 . The sloped facing surfaces of members  60  snuggly receive the handle shaft to ensure sufficient support. 
   While the invention may be susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and have been described in herein. However, it should be understood that the invention is not intended to be limited to the particular forms disclosed. For example,  FIG. 8  illustrates a portion of another inventive embodiment wherein the portion of handle member  24  between proximal end  86  and second coupler  22  is formed of a resilient steel spring member  24   a  that is angled away from the surface of member  16  to which it is attached by a ramp member  112 . In this embodiment spring steel member  24   a  provides the biasing means to bias handle  24  and coupler  22  toward and into engagement with first coupler  26  (see also FIG.  7 ). Although not illustrated other biasing assemblies are contemplated such as, for instance, a loaded helical spring within cylinder member  70  or some type of spring or bungee member between the first and second couplers  22  and  26 . 
   In addition, in at least some embodiments, instead of providing a biasing member to maintain the first and second couplers engaged, some type of mechanical retaining member may be provided. To this end, referring to  FIG. 9 , a schematic similar to the schematic of  FIG. 5  described above shows one embodiment where a clip assembly  119  includes a member  120  that extends from the top edge of the coupler surface formed by second coupler to a distal end  124  and a latch member  126  that is pivotally linked to the distal end of member  120 . Member  120  is dimensioned to extend past first coupler  26  when the first and second couplers are coupled. A distal end of latch member  126  forms a latching rib  130 . A rear surface  132  of first coupler  26  opposite the coupling surface  29  forms a recess  122  for receiving latching rib  130 . When couplers  22  and  26  are engaged and rib  130  is within recess  122 , the couplers are secured in their engaging state. To decouple the couplers  22  and  26  member  126  is pivoted about end  124  and handle  24  is rotated clockwise about axis  68  as illustrated in FIG.  9 . Other mechanical retaining mechanisms are contemplated. 
   Moreover, while the invention is described in the context of an assembly  10  where the gauge wheel  46  resides generally behind and partially laterally to one side of the disc  14 , other configurations are contemplated wherein wheel  46  resided entirely behind disc  14  or to the opposite side of disc  14 . Moreover, additional other wheels and assembly components may be secured to the main arm member or the gauge arm member such as, for instance, packer wheels, sensors, fertilizer tubes, etc. 
   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: