Abstract:
An agricultural harvesting machine includes a chassis and a threshing system carried by the chassis. The threshing system includes a rotor, a frame assembly and at least one concave carried by the frame assembly. A latch mechanism supports and secures the concave relative to the frame assembly and includes a concave support bar, a clamping bar and a quick-connect, over center latch for tool-less operation.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to agricultural harvesters such as combines, and more particularly to threshing or separating systems of such combines, and still more particularly to systems or structures for securing concaves in the threshing systems of such combines. 
     2. Description of the Related Art 
     An agricultural harvester known as a “combine” is historically termed such because it combines multiple harvesting functions, such as picking or cutting, threshing, separating and cleaning in a single harvesting machine. A typical combine includes a header which removes the crop from a field, and a feeder housing which transports the crop matter into a threshing rotor. The threshing rotor rotates within a perforated housing, which may be in the form of adjustable concaves, and performs a threshing operation on the crop, to dislodge the grain from other crop material. Once the grain is threshed, it falls through perforations in the concaves onto a grain pan. From the grain pan, the grain is cleaned on sieves in a cleaning system. A cleaning fan blows air through the sieves to discharge chaff and other debris toward the rear of the combine. Non-grain crop material, such as straw from the threshing system, proceeds through a residue system, which may utilize a straw chopper to process the non-grain material and direct it out the rear of the combine. The cleaned grain is transported to a grain tank onboard the combine. When the grain tank becomes full, the combine is positioned adjacent a vehicle into which the grain is to be unloaded, such as a semi-trailer, gravity box, straight truck, or the like; and an unloading system on the combine is actuated to transfer the grain from the grain tank into the vehicle. 
     More particularly, a rotary threshing or separating system includes one or more rotors which can extend axially (front to rear) or transversely (side to side) within the body of the combine, and which are partially or fully surrounded by a perforated concave. The crop material is threshed and separated by the rotation of the rotor within the concave. Coarser non-grain crop material such as stalks and leaves are transported to the rear of the combine and discharged back to the field. The separated grain, together with some finer non-grain crop material such as chaff, dust, straw, and other crop residue are discharged through the concaves and fall onto a grain pan where they are transported to the cleaning system. Alternatively, the grain and finer non-grain crop material may also fall directly onto the cleaning system itself. 
     The cleaning system further separates the grain from non-grain crop material, and typically includes a fan directing an airflow stream upwardly and rearwardly through vertically arranged sieves which oscillate in a fore and aft manner. The airflow stream lifts and carries the lighter non-grain crop material towards the rear end of the combine for discharge to the field. Clean grain, being heavier, and larger pieces of non-grain crop material, which are not carried away by the airflow stream, fall onto a surface of an upper sieve (also known as a chaffer sieve) where some or all of the clean grain passes through to a lower sieve (also known as a cleaning sieve). Grain and non-grain crop material remaining on the upper and lower sieves are physically separated by the reciprocating action of the sieves as the material moves rearwardly. Any grain and/or non-grain crop material remaining on the top surface of the upper sieve is discharged at the rear of the combine. Grain falling through the lower sieve lands on a bottom pan of the cleaning system, where it is conveyed forwardly toward a clean grain auger. The clean grain auger conveys the grain to a grain tank for temporary storage. 
     The concaves of the combine threshing system need to be changed for harvesting different types of crops. For optimum performance, concaves need to be replaced if excessively worn or damaged. It is known to secure concaves using threaded fasteners, such as bolts and the like, which require tools both for releasing the fasteners to disengage a concave for removal and to engage and tighten the fasteners to secure a replacement concave in position. Removing and replacing concaves with known securing systems can be difficult and time-consuming under shop conditions and even more difficult if performed in the field during a harvesting operation, when time is critical and nonproductive harvesting time is costly. 
     What is needed in the art is a concave securing system that can be operated more efficiently under typically experienced conditions to facilitate removal and installation of concaves in an agricultural harvester. 
     SUMMARY OF THE INVENTION 
     The present invention provides a concave securing mechanism having a latch mechanism that can be operated without tools under typically experienced conditions, for securing and releasing concaves in an agricultural harvester. 
     The invention in one form is directed to an agricultural harvester provided with a chassis and a threshing system carried by the chassis. The threshing system includes a rotor, a frame assembly and a concave including a securement portion. A securing mechanism connects the concave to the frame assembly and includes a support component in a fixed location relative to the frame assembly, a securing component movable relative to the support component, and a tool-less latch mechanism interconnecting the support component and the securing component with the securement portion captured between the support component and the securing component. 
     The invention in another form is directed to a threshing system of an agricultural harvester provided with a frame assembly, a concave including a plurality of securement portions, and a securing mechanism connecting the concave to the frame assembly. The securing mechanism includes a support bar axially rotatable at a fixed location relative to the frame assembly, a clamping bar movable relative to the support bar and applying clamping force against the plurality of securement portions, and a tool-less latch mechanism interconnecting the support bar and the clamping bar. 
     The invention in yet another form is directed to a securing mechanism connecting a concave to a frame assembly in an agricultural combine, provided with a plurality of securement portions extending from the concave, a support bar axially rotatable at a fixed location relative to the frame assembly and a clamping bar movable relative to the support bar and applying clamping force against the plurality of securement portions. A latch mechanism pivotally connects the clamping bar to the support bar. 
     The present invention, in a form thereof, advantageously provides a latch mechanism for concaves that operates quickly to release an installed concave and to secure a replacement concave in a combine harvester threshing system. 
     Another advantage of a form of the present invention is that the latch mechanism can be manipulated without the need for tools. 
     Yet another advantage of the present invention is that the latch mechanism can be operated easily and quickly, saving time. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of an embodiment of the invention taken in conjunction with the accompanying drawings, wherein: 
         FIG. 1  is a side view of an embodiment of an agricultural harvester in the form of a combine, which includes an embodiment of a concave latch mechanism of the present invention; 
         FIG. 2  is a perspective view of a portion of the threshing or separating system of the combine; 
         FIG. 3  is an elevational view of a portion of the threshing or separating system; 
         FIG. 4  is an enlarged fragmentary elevational view of a concave securing mechanism in the threshing system; 
         FIG. 5  is another perspective view of a portion of the threshing system; 
         FIG. 6  is another fragmentary elevational view of a portion of the concave securing mechanism; 
         FIG. 7  is a perspective view similar to that of  FIG. 5 , but illustrating the threshing system in a different maintenance condition; 
         FIG. 8  is a fragmentary elevational view similar to that of  FIG. 6 , but illustrating the concave securing mechanism in the maintenance condition shown in  FIG. 7 ; 
         FIG. 9  is a perspective view similar to those of  FIGS. 5 &amp; 7 , but illustrating the threshing system in yet another maintenance condition; 
         FIG. 10  is an elevational view similar to those of  FIGS. 6 &amp; 8 , but illustrating the concave securing mechanism in the maintenance condition shown in  FIG. 9 ; 
         FIG. 11  is a larger elevational view of a latch mechanism used in the concave securing mechanism shown in the previous drawings; 
         FIG. 12  is an elevational view of the latch mechanism shown in  FIG. 11 , but illustrating the latch mechanism disengaged; 
         FIG. 13  is an elevational view of the latch mechanism shown in  FIGS. 11 &amp; 12 ; but illustrating the latch mechanism in the condition of  FIGS. 7 &amp; 8 ; and 
         FIG. 14  is an exploded view of the latch mechanism. 
     
    
    
     Corresponding reference characters indicate corresponding parts throughout the several views. The exemplification set out herein illustrates an embodiment of the invention, in one form, and such exemplification is not to be construed as limiting the scope of the invention in any manner. 
     DETAILED DESCRIPTION OF THE INVENTION 
     The terms “grain”, “straw” and “tailings” are used principally throughout this specification for convenience but it is to be understood that these terms are not intended to be limiting. Thus “grain” refers to that part of the crop material which is threshed and separated from the discardable part of the crop material, which is referred to as non-grain crop material, MOG or straw. Incompletely threshed crop material is referred to as “tailings”. Also the terms “forward”, “rearward”, “left” and “right”, when used in connection with the agricultural harvester and/or components thereof are usually determined with reference to the direction of forward operative travel of the harvester, but again, they should not be construed as limiting. The terms “longitudinal” and “transverse” are determined with reference to the fore-and-aft direction of the agricultural harvester and are equally not to be construed as limiting. 
     Referring now to the drawings, and more particularly to  FIG. 1 , there is shown an agricultural harvester in the form of a combine  10 , which generally includes a chassis  12 , ground engaging front wheels  14  and rear wheels  16 , a header  18 , a feeder housing  20 , an operator cab  22 , a threshing and separating system  24 , a cleaning system  26 , a grain tank  28 , and an unloading auger  30 . 
     Front wheels  14  are larger flotation type wheels, and rear wheels  16  are smaller steerable wheels. Motive force is selectively applied to front wheels  14  through a power plant in the form of a diesel engine  32  and a transmission (not shown). Although combine  10  is shown as including wheels, it is also to be understood that combine  10  may include tracks, such as full tracks or half-tracks. 
     Header  18  is mounted to the front of combine  10  and includes a cutter bar  34  for severing crops from a field during forward motion of combine  10 . A rotatable reel  36  feeds the crop into header  18 , and a double auger  38  feeds the severed crop laterally inwardly from each side toward feeder housing  20 . Feeder housing  20  conveys the cut crop to threshing and separating system  24 , and is selectively vertically movable using appropriate actuators, such as hydraulic cylinders (not shown). 
     Threshing and separating system  24  generally includes a rotor  40  at least partially enclosed by and rotatable within a corresponding perforated concave  42 . The cut crops are threshed and separated by the rotation of rotor  40  within concave  42 , and larger elements, such as stalks, leaves and the like are discharged from the rear of combine  10 . Smaller elements of crop material including grain and non-grain crop material, including particles lighter than grain, such as chaff, dust and straw, are discharged through perforations of concave  42 . Rotor  40  is shown in a representative sense in that rotor  40  may be more than one rotor  40  and may be oriented generally in line with the direction of travel of combine  10 . So also, concave  42  can be more than one concave  42 , or more than one concave section commonly referred to as concaves. 
     Grain that has been separated by threshing and separating assembly  24  falls onto a grain pan  44  and is conveyed toward cleaning system  26 . Cleaning system  26  may include an optional pre-cleaning sieve  46 , an upper sieve  48  (also known as a chaffer sieve), a lower sieve  50  (also known as a cleaning sieve), and a cleaning fan  52 . Grain on sieves  46 ,  48 , and  50  is subjected to a cleaning action by fan  52 , which provides an airflow through the sieves to remove chaff and other lightweight impurities, such as dust, from the grain by making the lightweight material airborne for discharge from a straw hood  54  of combine  10 . Grain pan  44  and pre-cleaning sieve  46  oscillate in a fore-to-aft manner to transport the grain and finer non-grain crop material to the upper surface of upper sieve  48 . Upper sieve  48  and lower sieve  50  are vertically arranged relative to each other, and likewise oscillate in fore-to-aft manner to spread the grain across sieves  48 ,  50 , while permitting the passage of cleaned grain by gravity through the openings of sieves  48 ,  50 . 
     Clean grain falls to a clean grain auger  56  positioned crosswise below and at the front of lower sieve  50 . Clean grain auger  56  receives clean grain from each sieve  48 ,  50  and from a bottom pan  62  of cleaning system  26 . Clean grain auger  56  conveys the clean grain laterally to a generally vertically arranged grain elevator  60  for transport to the grain tank  28 . Tailings from cleaning system  26  fall to a tailings auger trough  58 , and are transported via a tailings auger  64  and a return auger  66  to the upstream end of the cleaning system  26  for repeated cleaning action. A pair of grain tank augers  68  at the bottom of the grain tank  28  convey the clean grain laterally within the grain tank  28  to the unloading auger  30  for discharge from combine  10 . 
     The non-grain crop material proceeds through a residue handling system leading to discharge from straw hood  54 . The residue handling system can include a chopper, counter knives, a windrow door and a residue spreader, not shown but well understood and familiar to those skilled in the art. 
     Now, additionally referring to  FIGS. 2 through 4 , there is shown a concave securing mechanism  70  by which concave  42  is held in position in threshing system  24 . Securing mechanism  70  includes a support component in the form of a support bar  72 , a clamping or securing component in the form of a movable clamping bar  74  and a plurality of latch mechanisms  76  interconnecting support bar  72  and clamping bar  74 . In closed or secured positions of latch mechanisms  76 , support bar  72  and clamping bar  74  are secured against bottoms and tops, respectively, of a plurality of securement portions  78  of concave  42 . In the exemplary embodiment shown, three latch mechanisms  76  are used; however, it should be understood that specific applications of a concave securing mechanism  70  hereof may use more or fewer latch mechanisms  76 . 
     More specifically, support bar  72  is fastened in a fixed location relative to a frame assembly  80  of threshing and separating system  24 , which is supported by chassis  12 . While fixed in location, support bar  72  is rotatable about the longitudinal axis thereof. Support bar  72  is both strong and rigid, providing a firm support for concave  42 . Securement portions  78  of concave  42  are lateral extensions of concave  42 , and are configured to rest on and against support bar  72 . Accordingly, each securement portion  78  defines a curved lower edge  82  conforming to at least a portion of the surface of support bar  72  so as to engage support bar  72  while allowing support bar  72  to rotate relative thereto even when the securement portions  78  are placed on and resting against support bar  72 , which is supporting the weight of concave  42 . 
     Clamping bar  74  is movable relative to support bar  72  and frame assembly  80 , and is sufficiently strong and rigid so as to apply clamping load against the top of securement portions  78 . Accordingly, each securement portion  78  defines a shaped upper edge  84  to be engaged by clamping bar  78 . With latch mechanisms  76  closed, as will be described hereinafter, each securement portion  78  is sandwiched between support bar  72  there below and clamping bar  74  there above, to be held in fixed positions relative to frame assembly  80 . 
       FIGS. 5 &amp; 6  illustrate the relative positions of concave securing mechanism  70  and concave  42  with latch mechanisms  76  in closed or locked conditions. The configuration shown in  FIGS. 5 &amp; 6  is generally the operating condition for combine  10 , with concave  42  locked into position as a result of clamping force provided by clamping bar  74  against securement portions  78 , which are engaged against support bar  72 . 
       FIGS. 7 &amp; 8  illustrate the relative positions of concave securing mechanism  70  and concave  42  when latch mechanisms  76  are initially adjusted to open or unlocked conditions. The configuration shown in  FIGS. 7 &amp; 8  is the initial release condition of latch mechanisms  76 , wherein clamping force against securement portions  78  is released, and clamping bar  74  is disengaged from securement portions  78 . 
       FIGS. 9 &amp; 10  illustrate the relative positions of concave securing mechanism  70  and concave  42  with latch mechanisms  76  open or unlocked as in  FIGS. 7 &amp; 8 ; but with further adjustment of securing mechanism  70  to allow removal of concave  42 . Support bar  72  has been rotated to pivot clamping bar  74  away from securement portions  78 . The configuration shown in  FIGS. 9 &amp; 10  has the upper, movable portions of latch mechanisms  76  moved fully out of the way so that concave  42  can be removed for repair or replacement. 
     As illustrated in the series of  FIGS. 5-10 , the components of securing mechanism  70  remain connected within combine  10  and do not need to be removed when disengaging a concave  42  that is being removed from the combine. Accordingly, all parts remain connected and available to re-engage a reinstalled or replacement concave. 
     Latch mechanisms  76  extend between and are connected to support bar  72  and clamping bar  74 . All of the latch mechanisms  76  are similar to one another in both construction and operation.  FIGS. 11-13  illustrate one of the latch mechanisms  76  in latched, unlatched and partially opened conditions, respectively. 
     Now referring more specifically to  FIGS. 11-13  and particularly to  FIG. 14 , one of the latch mechanisms  76  is shown and will be described. In the exemplary embodiment shown and described herein, each latch mechanism  76  includes a lower bracket  86  connected to support bar  72 , and a collar  88  connected to clamping bar  74 . Collar  88  is connected to bracket  86  at a pivotal connection  90  at one side of latch mechanism  76 , and a quick-release, over center latch  92  is operable between bracket  86  and collar  88  generally at an opposite side of latch mechanism  76  from pivotal connection  90 . 
     More specifically, in the exemplary embodiment shown, bracket  86  includes spaced first and second plates  94 ,  96  engaged on support bar  72  and defining extensions  98 ,  100  near confronting corners thereof. Collar  88  is a body having a thickness so as to fit between first plate  94  and second plate  96  and particularly between first and second extensions  98 ,  100  thereof. A pivot pin  102  including a head  104  connects collar  88  to bracket  86  pivotally. Pivot pin  102  extends through extension  98 , collar  88  and extension  100 , and is held or secured by a key  106  at the opposite end of pin  102  from head  104 . Accordingly, collar  88  is sandwiched between first plate  94  and second plate  96  and is held about a pivotal axis defined by pivot pin  102 . As a result, clamping bar  74  is allowed to move relative to support bar  72  in that collar  88  pivots relative to bracket  86 , collar  88  pivoting about the axis defined by pivot pin  102 . It should be understood that the pivotal connection  90  between bracket  86  and collar  88  shown and described herein is merely exemplary, and other types of pivotal connections and structures can be used. 
     At an opposite side of collar  88  from pivotal connection  90 , collar  88  defines a hook  108  opening generally upwardly and generally in line with latch  92 . 
     Quick-release, over center latch  92  includes a base  110  secured relative to first and second plates  94 ,  96  and including spaced tabs  112 ,  114  extending from base  110 . A handle  116  is connected to tabs  112 ,  114  at pivotal connections  118 ,  120 , respectively, near one end of the handle  116 . A pivot arm  122  is connected to handle  116  about a pivotal connection  124  spaced from pivotal connections  118 ,  120 . A ring  126  is provided at the distal end of pivot arm  122  and is configured to engage hook  108 . Arm  122  can be a threaded arm  122  configured to engage a threaded base  128  of ring  126 , so that an effective overall length or arm  122  from pivotal connection  124  to ring  126  can be adjusted by rotating base  128  more deeply or more shallowly onto threaded arm  122 . 
     As described above, latch  92  is a so-called “over center” latch. With pivotal connections  118 ,  120  spaced away from base  110  by tabs  112 ,  114 ; the latch is self-securing when handle  116  is rotated downwardly toward or even against base  110 , when ring  126  is engaging hook  108 . Over center latches can be operated quickly and easily both when latching and when unlatching, and generally tools are not required for operating the latches. The latches can be operated much more quickly than common threaded fasteners, such as bolts, thereby expediting and simplifying the process for removing and installing concaves. Further, latches  92  draw together support bar  72  and clamping bar  74  against securement portions  78  with a desired clamping force by adjusting the effective length of pivot arm  122  as described above. Proper adjustment ensures a proper, desired clamping force, reducing the risk of either over-tightening or under-tightening as can occur when threaded fasteners, such as bolts, are used. 
     At an opposite end of concave  42  from concave securing mechanism  70 , the concave is held by an anchor structure  130 , and adjustment mechanisms  132 ,  134  are provided for adjusting an overall position of concave  42  within threshing system  24  and particularly with respect to rotor  40  thereof. Various types and constructions of anchor structure  130  and adjustment mechanisms  132 ,  134  can be used, as those skilled in the art will understand readily. 
     In the use of a concave securing mechanism  70  when removing an installed concave  42 , from the position shown in  FIGS. 1-6 , each latch  92  is released by lifting the handles  116  thereof, thereby elevating the rings  126  so that the rings  126  can be disengaged from the hooks  108 . Clamping force against securement portions  78  is thereby released. Clamping bar  74  is disengaged from securement portions  78  and is moved away by rotating collars  88  about pivotal connections  90  to the position illustrated in  FIGS. 7 &amp; 8 . Thereafter, support bar  72  is rotated about its axis to move clamping bar  74  and latch mechanisms  76  laterally away from concave  42 . Accordingly, as shown most clearly in  FIGS. 9 &amp; 10 , concave  42  is no longer restricted by clamping bar  74  and collar  88  from above and can be slid along and/or lifted away from support bar  72  for removal from the combine  10 . 
     When concave  42  or a new concave  42  is being installed, the securement portions  78  thereof are rested on support bar  72 , with clamping bar  74  and latch mechanisms  76  generally in the positions illustrated in  FIGS. 9 &amp; 10 . With the concave positioned on support bar  72 , support bar  72  is rotated, but in the opposite direction from that described prior to removing concave  42 , until reaching generally the position shown in  FIGS. 7 &amp; 8 . Clamping bar  74  is placed against the shaped upper edges  84  of securement portions  78 , each handle  106  is lifted to elevate arms  122  and rings  126  are engaged over hooks  108 . Handles  116  are moved downwardly to supply clamping force from clamping bar  74  against securement portions  78  supported on support bar  72 . 
     While this invention has been described with respect to at least one embodiment, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims.