CA1225835A - Crop gathering head and belt, sprocket and sheave therefor - Google Patents

Abstract

Abstract of the Disclosure CHOP GATHERING HEAD AND BELT, SPROCKET AND SHEAVE THEREFOR A crop gathering head 10 including crop gathering belt 11, 12 of reinforced elastomeric material and its associated driving sprocket 30 and idler sheave 50 is described. The belt 11 or 12, sprocket 30 and sheave 50 system may be used to convey crops into a combine. The belt 11 or 12 includes a plurality of cleats 20 of elastomeric material on its top surface 18 and a plurality of equally spaced driving lugs 24 of elastomeric material on its bottom surface 19. The sprocket 30 has first and second sides 31, 32 respectively and comprises a plurality of equally spaced apart radially projecting teeth 33 separated by first and second cavities 34, 34' respectively. The first cavities 34 are open only to the first side 31 of the sprocket 30. The second cavities 34' are open only to the second side 32 of the sprocket 30. The depth D of each cavity exceeds the height H of each driving lug 24 of the belt 11 or 12 and the cavities 34, 34' are shaped such that foreign material, for example, corn kernels, mud and ice do not clog the driving sprockets 30 and belts 11 or 12 and disable the system. Each belt 11 or 12 is also entrained about an idler sheave 50 that includes a cylindrical hub 51 having a pair of axially spaced radially projecting flanges 52, 53 respectively thereon. The inner side surfaces 54 of the flanges 52, 53 converge in a direction toward the axis of rotation 55 of the sheave 50. Each flange 52 or 53 is interrupted in the circumferential direction of the sheave 50 to provide a self-cleaning effect upon engagement with its associated belt 11 or 12.

Description

CRDP GA~HERING ~DE~D AND BELT, SPROCKET, AND SHEAVE THEREF~R
The abs~ract is not to be taken as limiting the in~7ention of this application and in order to understand the full nature and 5 extent of the technical disclosure of this application reference ~ust be made to the acccmpanying drawing and to the following detailed description.
This invention relates to a crop gathering head and ~.ore particularly to a belt, sprocket and sheave system for use in a 10 crop gathering ~achine.
` m ere are various configurations of machines to be used in harYesting of crops such as corn in which the staIk of the crop is dra~n into the forward end of the gathering portion of the h2_vester by ~ans of metallic chains including tines or fingers 15 attached thereto. The staIk of the co m enters a narTow slot which is elongated in the fore and aft direction of the ~achine, i.e.
parallel to the direction in which the machine moves. The slot is of sufficient width to accept the stalk but not permit the e~rs o~ ~ _ co~n to fall through. A m~chanism ~unted bel~ the pl~n~r faces 20 forming ~he slot draws the st~Lk dow~war.dly through the slot C thereby separating the ears from the stalk. After separati~n~ the `~ ears are conveyed by means of:a pair of opposed c,hains to the re~r of the gathering head for further processing; e.g., removal of the ~ husk amd sep æ ation of the corn kerneIs from the ear in kno~n 25 ma~ner.
Prior art gather m g mech~nisms which employ metallic chain and sprockets, although they have been used with considerable success, generate a considerable a~unt of noise and vibration and of course are subject to rusting and loss of tension as they wear at thei~
30 links. Additionally such metallic chains æ e like~y to damage the relainder of the harvesting ~achine should the chain or a portion of it pass through the m,ech~nisn. Also9 use of Fetallic gathering chains at ground speeds of the harvester ~n excess of about~four , ~,, .
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(4) miles per hour results in very rapid wear of the chains. To extend their service life, metallic chains requlre periodic lubrication.
An aspect of the invention is as follows:
A crop gathering head including a pair of belts driven synchronously, running parallel to each other in a common plane, the direction of travel of one belt being opposite that of the other, each belt having a top surface, the top surfaces of the belts being adjacent and opposed to one another, the adjacent to surfaces moving in the same direction at the same surface speed, the top surface of each belt including a plurality of identical cleats of elastomeric material projecting substantially perpendicularly therefrom, each of the cleats when viewed in a longitudinal section of the belt being of triangular configuration with the base of the ~riangle being joined to the top surface of the belt each of the cleats when viewed in longitudinal section of the belt is of hollow triangular configuration, the bottom surface of each belt includes a plurality of integrally molded driving lugs projecting substantially perpendicularly therefro~, each of the cleats is of a transverse dimension less than that of the belts, each individual cleat begins at a point opposite one driving lug and extends in the longitudinal direction of the belt to a point opposite the next adjacent driving lug, the apex of each cleat being positioned longitudinally between a pair of driving lugs.
The features and advantages of the invention will be better understood from consideration of the following detailed description taken in conjunction with the accompanying drawings in which primes (e.g. 1 s ~

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~ 2A- l~ZS835 versus 1') are used to distinguish between various embodiments:
Figure 1 is a to plan view of a crop gathering head embodying the invention;
Figure 2 is an enlarged longitudinal section of a portion o a preferred embodiment of a belt according to the invention;
Figure 3 is an enlarged sectional vie illustrating a drive sprocket according to the invention with the belt of the invention engaged therewith being shown in transverse section;
Figure 4 is a side view of a drive sprocket according to the invention;

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Figure 5 is a sectional view of a drive sprocketaccording to the invention, the section being taken along line 5-5 of Figure 4;
Figure 6 is a side view of an idler sheave accord-ing to the invention; and Figure 7 is an end view of the sheave of Figure 6 with the belt of the invention engaged therewith being shown in transverse section.
Referring to Figure 1 there is shown a crop gather-ing head 10 that includes a pair of synchronously drivenbelts llA, 12A. Belts 11,12 run parallel to one another ~ in a common plane located above the metal flanges 14 i which form the slot 15 of the crop gathering head 10.
The direction of travel of belt 11 is counterclockwise and while the direction of travel of belt 12 is clock-wise thus the belts 11 and 12 work in concert to trans-port ears of corn (not illustrated) from the forward end 16 to the aft end 17 of the crop gathering head 10 after the ears have been snapped off by withdrawing the stalk downwardly through the slot 15 between 13~

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flanges 14. ~elts 11 and 12 as well as thelr driv m g systems are identical except for their arrange~nt on the machine; one being the ~irror image of the other.
Referring now to ~igure 2 in addition to Figure 1, each belt 11, 12, 11', 12' includes at top surace 18, 18' and a bottom surface 19, 19'. The top surface 18, 18' is the surface of the belt 11, 12, 11', 12' that is directed away from the drive sprocket 30 and idler sheave 50. The bott~m surface 19, 19' is that surface of the belt 11, 12, 11', 12' nearest to the drive sprocket 30 and sheave 50. The top surfaces 18, 18' of belts 11, 11' and 12, 12' are adjacent to and opposed to one another over the crop gathering flanges 14. The top surface 18, 18' of each gathering belt 11, 12, ~-~ 11', 12' m cludes a plurality of identical cleats 20, 20' of elastomeric material. Each cleat 20, 20' projects substantially ` 15 perpendicularly from the top surface 18, 18' of its respective '~ belt. In a preferred e~bodi~nt each cleat 20' when viewed in longitudinal section of the belt 11', 12' (as shswn in Figure 2) is `~ of tri~ygular configuratîon with the base of the triangle being joined to the top surface 18' of the belt. Each cleat 20' when - 20 viewed in lcngitud~nal seetion of the belt 11' or 12' has a j longitudinal dimension X at its base. The cleats ~0' are unifor~ay c spaced apart from one another by their pitch Y. The tenm pitch as `~ e~ployed herein means the distance between succeeding lugs or cleats as measured from a given point on one cleat to the identical 25 point on the next cleat or lug. In the particular~y preferred ~- e~bodiment shown each cleat 20' when viewed in longitudinal section , of the belt 11', 12' is a hollow triangle one leg 21 of the triangle extends from the base of the cleat 20' from a point opposite the location of 2 driving lug 24', the other leg 22 of 30 the triangular configured cleat 20' extends from a point opposite the next driving lug 24A'.
~ The cleats 20, 201 possess sufficient stiffness so as to b positively con~ey the ears of corn from the forward end 16 to the aft end 17 of the gathering head 10. The hollow trianO~ular configuration 20' shown accom?lishes this with a ~inim~m a~ount of 'f; :. , ~ L~ S ~3~
elasto~eric material. It is understood that other cleat configurations will work, however. Due to the inherent resilience and flexibility of the elasto~eric material of which the cleats are formed, should the harvesting mach-ine become ja~ed the cleats 20, 20' will then deflect without being damaged or causing damage to other parts of the crop gathering head 10.
A plurality of driving lugs 24, 24' of elastomeric material project from the bottom surface 19, 19' of the belt 11, 12, 11', 12'. Each drivLng lug 24, 24' projects generally perpendicularly relative to the bottom surface 19, 19' of the belt 11, 12, 11' or 12'. Each drivi-ng lug 24 ~nen viewed in a longitudinal section o the belt 11, 12, 11' or 12' is of trapezoidal configuration wi~h ~`` t'ne base of the trapezoid joined to the bottom surface 19, 19' of tne belt 11, 12, 11' or 12' Each lug 24, 24' has a longitudinal di~nsion at its base of A. Succeeding lugs 24, 24' æ e spaced apart from one another in the longitudinal direction of the belt 11, 12, 11' or 12' by lug pitch ~.
.Referring now to Figure 3 it is seen that each of the drivIng lugs 24' when vie~ed in a transverse sec~i~n of the belt 11' or 12' is of tr2pezoidal con~iguration with the base o~ the trapezoid joined to the bottom surf2ce 1~' of the belt. The base of each cleat 24' h2s a tr2nsverse di~ension T which is less than the transverse dicension S of the belt 11' or 12'. The sides 25' of each drivè lug 24' converge In a direction away from the bottom surace 19' of the belt ll' or 12'.
Each belt 11, 12, 11' or 12' is o reinforced elastomeric ~ater;al and includes a fle~ible reinforced structure 22, 22' ~æ~Jng a top s~rface 18, 18' and a botto~ surface 19, 19' located intercediate the crop gathering cleats 20, 20' and the driving l~gs 24, 24'. The structure 22, 22' has cne or re longitudinally extendin~ h' gh elastic ~dulus cords 23 e~bedded therein; the longitu~L~ally extenoi~g center plane of the cords defining the pitch l ne of the belt. A layer 27 of light~eight woven or knitted f~ric ~ay be positioned adjacent the top surface 18, 18' and .

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bottom surface 19, 19' of the belt structure 22, 22' to pr~ide increased durability of the belt ll, 12, 11' or 12'.
Referring n~w to Figures l, 3, 4 and 5 therein is shown a driJe sprocket 30 according to the invention, both individually and in conjunction with the belt 11, 12, ll' or 12' of the i~vention and the ga~hering head 10 of the inventian. Each driving sprocket 30 has a first side 31 and a second side 32 as shGwn in Figure 5 and includes a plurality of equally spaced apart radially projectIng teeth 33 (best seen in Figures l and 4 for engage~ent with the driving lugs 24, 24' of the belt 11, 12, 11' or 12'~.
Each sprocket tooth 33 is separated from the next adjacent sprocket tooth 33 by a cavity 34 that is open only to one side of the ~ sprocket 30. Referring now to Figure 4 it is seen that the numbers 60 and 61 have bet~een them a cavity 34 that is open only to the first side of the sprocket ~ereas the nwmbers 62 and 63 - have between them a cavity 34 that is open only to the secGnd side 32 of the sprocket. The sprocket 30 includes a plurality of flange portions 35 located on alternating sides of the sprocket. Each fla~ge portion 35 is of the sa~e radial projection as tha~ of the pair of adjacent teeth between whic~ that flange portic~l extends.
Each flange portion 35 projects generally radially outwardly perpendicularly to the axis of rotation 36 of the sprocket 30.
Thus the cc~nbination of the alternating flange portic~ls 35 and ` driving teeth 33 with the lugs of 24, 24' of the belt ll, 12, 11' or 12' positively transmit pc~er to the belt and keep the belt frc~
nKnnLng ~n a direction parallel to the sproclcet axis 36 and out of engage~ent with the driving teeth 33. In a preferred emboc~nent `~ the teeth 33 of the driving sprocket 30 are of a radial dimension D
q that is considerably greater than the amount H which a driving lug 24, 24' projects perpenc~cularly from the bottc~n surface 19, 19' of the belt 11, 12, 11' or 12'. This considerable clearance between the tips 28 of the driving lugs 24, 24' and the bottc ~ 37 of ~he cavities 34 is provided to inhibit disengagement of the belt 11, 12, 11' or 12' through entrainment ~nd entrapment of the crop or clebris such as mud, Lce and rocks which ~y be encountered under .

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certain h2rvesting conditions, for example, when the crop has fallen over and is not standing upright at the time of harves~.
Because each cavity 34 is open to a side of the drive sprocket 30 any material which would otherwise be entrained in the bott~ 37 of the cavity 34 is free to exit to the side. Preferably the bott~m surface 37 of each sprocket cavity 34 slopes toward the axis of rotatiQn 36 of the sprocket 33 in a l;rection away from t~e respective flange portion 35 to facilitate self-cleaning of ~he sprocket. It is preferable that the radially projecting flange portion 35 be connected to the cavity bottom surface 37 by an arcuate surface 38 to facilitate self cleam ng. The fore and aft s~rfaces 39, 40 respectively of the cavity 34 should join to the botto~ surface 37 of the cavity via arcuate surfaces or the bottom surface 37 of the cavity 34 should itself be an arcuate surface as shown. In the accompanying dra~nng the bottom surfaces 37 are sh~n to be conical. I~hen these cu~ved surfaces are co~binpd as described and shown in FigurPs 4 and 5 the engagement of the driving lugs 24, 24' of the belt 11, lZ, 11' or 12' with its associated sp_oc~et 30 serves to push dcwr~ardly and outwardly any debn s tha~ ~ay otherwise bec~me entrapped in the drive sprocket 30.
Referring n~w to Figures 5 &nd 7 as well as Figure 1 there is sho~n a sheave 50 or idler pulley according to the invention. -The C `` sheave includes a cylindrical hub 51. A pair of axially spaced ~langes 52, 53 project ral;~lly from the hub 51. The inner side surfaces 54 of the flanges 52, 53 converge in a direction t~ward the ax~s of rotation 55 of t~R sheave 50 form m g a circ~2ferenti211y ex*end;r~ groove 58 between them. Each of the fl&~es 52, 53 is Interrupted Ln the circumferential direction of the s~ave 50. The interruptions of one of the flanges 52 are not aligr.ed with the interruptions of the other 53. As shown in Figure 7 the height H of each drive lug 24' corresponds to the radial ~rojecticn of the flaræes 52 and 53. Thus in the belt and sheave co~bir~tion as the belt 11, 12, 11' or 12' engages the sheave 30 the tips 28 of the drive lugs 24' contact the outer c~lindrical .

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surface 56 of the hub 51 and the edge portions 29 of the belt structure 22 contact the radially outermost surfaces 57 of the flanges 52, 53. Th~ flanges 52, 53 of the sheave 50 are axially spaced ap~rt so that the drive l~gs 24' do not wedge between the flanges 52, 53 as in a conventional V-belt and pulley system.
The flanges 52, 53 serve to guide the belt. The flanges 52, 53 are not intended to transmit power from the belt 11, 127 11~ or 12' to the sheave 50. Because the flanges 52, 53 ~re interrupted in the circumfe-rential directio.n of the sheave 50 foreign material that might otherwise become entrapped in the bottom of the circumferential groove 58 of the sheave 50 is able to exit to the sides 59, 64 of ~he sheave 50. In a preferred e~bodiment the . circumferential distance between the interruptions of ea~h flange 52, 5~ of the sheave 50 is not an integral ~Lltiple of the driving lug pitch B so as to ensure that all porti~ns of the sheave 50 eventually contact the longitudinal sides 25 of the driving lugs 2 and thereby even out wear of the belts ll or 12 and associated sheave 50. The interruptions of one flange 52 are not aligned ~ith the interruptions of the other flange 53 so as to assure guiding . 20 and control of the belt 11 or 12 at all t~mes. The inte m ~tion of the flanges need not be of the same circumferent~al extent shc~n to be effective. The particular emboc~ nt shc~wn facilitates mol~;ng of.the sheave.
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~;~.3 The main reinforcing cords 23 of the belt 11 or 12 are of high tensile modul~s material. Fiberglass or aramid are preferred for cords 23 althcn~h it is believed that nylc~n, polyester or the l~ke may also be e~ployed. High tensile loac~ng of the belt 11, 12, 11' or 12' can occur at those ti3es when an ear of corn or a stalk becomes lodged in the machine.
The dri~Ing lugs 24, 24' of the belt ll, 12, 11' or 12' of the preferred en~odiment described and shu~n herein are of truncated pyramidzl configuration and are not involute or conjugate. The sprocket 50 as shcwn is of a design that facilitates entry and exit of the driving lugs 24, 24' of the belt ll, 12, 11' or 12' by providing clearance for the corners 43 and tip 28 of each driving . . .

. ~ , -8- ~L~2 5~3~3~j lug 24, 241. Belts have been made utilizing elast~ner material that is a blend of natural rubber and synthetic isoprene blended.
However it is believed that other elastomeric or resilient materials for example, chloroprene or polyurethane or thei like would serve equally well.
Referring to Figure 1 it is seen that the leading edge 42 of each cleat 24 of the belt 11 or 12 is preferably tapered. The tapered leading edges 42 of each pair of opposed cleats thus tend to force the dislodged ears of coxn toward the fore and aft di~ected centerline of the gatherLng head 10 and facilitate withdrawal of each cleat 20 from the ear(s) of corn that it is conveying as the cleat begins to rotate around its associated drive ~; sp ocket 30 at the aft end 17 of the gathering head 10. The triangular ccnfiguration of the cleats 20' of belt 11 or 12' provide tapered leading edges to similarly facilitate withdxawa~ of each cleat 20' from the ears of corn.
The sprockets 30 and sheaves 50 are preferably made of ultra hign molecular weight polye-hylene. This material possesses sufficient st-ength and rigidity for ~his ~pplication. Use of this material is advantageous because it is not subject to rusting or corrosicn and its low coefficient of friction aids in the desired self-cleani~g action~ Of course, plastics including rein~orced plastics or metals may be used in construction of the sproc~ets and sheaves. ~hen ultr2 high ~olecular weight polyethylene is used, each sprocket or sheave preferably includes a metal insert 39 or 59 concentrically positioned in its hub.
The cl~ats 20 are shcwn ;r. Flgure 1 .o be aligned with one &~C,ho- This iS not required. I~e cleats 20 may be staggered rel2tive to Gne another.
It is to be u~derstood that the relative positions of the a~i~n~g sprockets and idler sheaves could be reversed such that the driving sp~oc~ets would be located at the for~7ard end 16 of the mac~ e that first engages the crop.
~nilè certain representative embodiment and its details have been described for the purpose of illustrating the invention it ~ ..

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~11 be apparent to those skilled in the art that various changes and ~cdifications m~y be made theréin without departing fram the spirit or scope of the invention, ~. .

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Claims

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A crop gathering head including a pair of belts driven synchronously, running parallel to each other in a common plane, the direction of travel of one belt being opposite that of the other, each belt having a top surface, the top surfaces of the belt being adjacent and opposed to one another, the adjacent top surfaces moving in the same direction at the same surface speed, the top surface of each belt including a plurality of identical cleats of elastomeric material projecting substantially perpendicularly therefrom, each of the cleats when viewed in a longitudinal section of the belt being of triangular configuration with the base of the triangle being joined to the top surface of the belt each of the cleats when viewed in longitudinal section of the belt is of hollow triangular configuration, the bottom surface of each belt includes a plurality of integrally molded driving lugs projecting substantially perpendicularly therefrom, each of the cleats is of a transverse dimension less than that of the belts, each individual cleat begins at a point opposite one driving lug and extends in the longitudinal direction of the belt to a point opposite the next adjacent driving lug, the apex of each cleat being positioned longitudinally between a pair of driving lugs.