Title of Invention

AN IMPROVED THRESHER FOR SEPRATION OF GRAINS

Abstract

A thresher comprising a stator disposed along the longitudinal axis of the thresher, a rotor within said stator and also disposed along the longitudinal axis, said stator having a feed zone for receiving the standing crop, said stator having a threshing zone also disposed along the longitudinal axis, a concave disposed in said threshing zone and bdbw of said rotor, a collection zone for receiving the grains from said concave, a straw discharge zone having a discharge outlet at an end of said thresher opposite to the feed zone.

Full Text

This invention relates to a thresher for causing a separation of grains from the straw of an agricultural crop. Though reference is made herein to a thresher provided with a harvester combine, such a reference is only by way of only an exemplary embodiment and without intending to imply any limitation on the scope of the invention. Thus, the thresher of the present invention may also be used in independent to a harvester combine. PRIOR ART A thresher known in die art and provided in a harvester combine normally comprises cutting blades provided in the forward end of the combine for cutting a standing crop. A rotatable reel is also provided in the forward end of the combine and presses the standing crop to a conveyor worm and fed to a thresher drum through a feed conveyor. The thresher drum is disposed in a dtrectton vertical to the longitudinal axis of the harvester combine so that the separated straw is also discharged along the longitudinal axis. In such a known construction, the thresher drum has outwardly projecting lugs or teeih which co-act with a stationary concave plate disposed below of said drum and in a spaced relationship thereto. Further, a guide drum having a flap or cover is provided above and in the proximity of the thresher drum. Such an arrangement causes an impact and rubbing action, depending on the agricultured produce. The grains with the chaff separated from the straw pass through the perforated concave plate and are fed to a pair of stepped sieves by a vibratory stepped bed. A blower is disposed below the vibratory stepped bed for causing a separation of the chaff from the grain. The grain from the sieves collect in a pan and by an elevator are fed to a grain tank. The grain tank has an outlet The harvester combine further comprises a straw walker disposed longitudinally within the harvester combine housing. The guide drum guides the straw separated from the grains onto the straw walker. The straw walkers are perforated so that residual grains entrained in the straw are separated and pass through the perforations while the straw moves along the longitudinal axis and discharged from the opposite end of the harvester combine. In the aforesaid known construction, the shaft for rotating the thresher drum is disposed at right angles to the longitudinal axis of the thresher. OBJECTS OF THE INVENTION An object of this invention is to propose an improved construction of a thresher. A further object of this invention is to propose a thresher which obviates the disadvantages associated with the prior art. Further objects and advantages of this invention will be more apparent from the ensuing description. DESCRIPTION OF INVENTION According to this invention there is provided a thresher comprising a stator disposed along the longitudinal axis of the thresher, a rotor within said stator and also disposed along the longitudinal axis, said stator having a feed zone for receiving the standing crop, said stator having a threshing zone also disposed along the longitudinal axis, a concave disposed in said threshing zone and below of said rotor, a collection zone for receiving the grains from said concave, a straw discharge zone having a discharge outlet at an end of said thresher opposite to the feed zone. As described hereinabove, the thresher of the present invention may be used with a harvester combine or otherwise. The thresher comprises a feed zone for receiving the cut standing crop, which is then fed to a separation or threshing zone. The separation zone comprises a rotor disposed along the longitudinal axis of the thresher. The rotor comprises a drum with a shaft is disposed within said drum and connected to a motive source. In accordance with one embodiment, the rotor has spaced fingers. In accordance with another embodiment, the rotor has spaced rasp bars in the separation zone and pegs in the straw collection zone. The separation zone further comprises a stationary stator disposed in a spaced relationship above said drum and extending along the longitudinal axis. In accordance with one embodiment of this invention, a helix is provided on the inner surface. The separation zone further comprises a concave perforated plated disposed below of said rotor. The grains pass through said perforated concave plate and discharged onto stepped sieves. A blower is provided for removal of the chaff. The rotor has an inlet and outlet end, a discharge of the separated straw being effected from the outlet end. The inlet of the rotor extends into a conical section of the rotatable drum with a helix for feeding the cut crop from the feed zone to the separation zone. The separation zone is capable of causing a rubbing or impact action. However, if required, suitable additional means may be provided for causing a rubbing action. The separated grain from the stepped sieves are collected in a collection zone and then fed to the grain tank. DESCRIPTION WITH REFERENCE TO DRAWINGS Further objects and advantages of this invention will be more apparent from the ensuing description when read in conjunction with the accompanying drawings and wherein. Fig. 1 shows the conventional thresher provided in a harvester combine. Fig. 2 shows a side sectional view of the thresher provided in a combine harvester in accordance with one embodiment FigJa to 3c show the concave plate provided in the thresher. Fig. 4 shows a side sectional view of another embodiment of a thresher provided in a combine harvester. Referring to fig. 1, the known thresher system provided in a harvester combine comprises a pan 3 at one end of the harvester and co-acting with a reel 1 and such that a standing crop 2 is fed into pan 3 by reel 1. The cut crop is fed to a conveyor 6 through a feeler anger 4 having prongs 5. The discharge end of conveyor 6 discharges the cut crop into a thresher 7. As apparent in fig. 1 thresher 7 includes a thresher drum disposed in an axis vertical to the longitudinal axis of the thresher. A concave 8 is disposed below thresher drum 7 and in a spaced relationship thereto in order to receive the grains and the straw. Grains pass through concave 8 onto a stepped bed 13. A stone trap 9 is provided in the proximity of concave 8 so as to prevent the entry of stones onto stepped bed 13. The grains from stepped bed 13 are blown onto a hinged screen 14 by means of a blower 16 disposed below of said stepped bed 13. Grains from hinged screen are conveyed by a screw conveyor onto a grain elevator 21 and screw conveyor 24 to a grain tank 22 having a discharge anger 23. A further adjustable sieve 18 is provided below hinged screen 14, and the grains are conveyed in a manner as described hereinabove. Reference is now made to the straw separated from the crop by thresher drum 7. Straw separated from the grain is discharged onto a straw walker 11 by a guide drum 10. A baffle plate 12 guiding the flow of straw onto said straw walker 11, and the straw is ultimately discharged from the opposite end of the combine. As shown in fig. 1 a chaffer rack 17 and screw 15 is provided with the straw system of the thresher. Reference is now made to fig. 2 which illustrates one of the embodiments of the thresher provided in a harvester combine. The thresher of fig.2 is used for crops such as paddy and where an impact action is required for causing a separation of the grains from the straw in distinction to a rubbing action for standing crops such as wheat or maize, and as shown in fig-4. The apparatus consisting of the reel section for cutting of the standing crop and feeding it into the feed zone A of the thresher is the same as that of the prior art. Thus, for purposes of brevity, the same reference numerals 1 to 6 as provided in fig. 1 are also provided in figs. 2 and 4 for designating like parts. Thus, the reel section comprising of parts having reference numerals 1 to 6 do not form a concept of the present invention. The present invention resides in a thresher comprising a rotor 17 disposed within a stator 21. Stator 21 is disposed along the longitudinal axis. The rotor comprises a rotatable shaft or drum 17 disposed within stator 21. The rotor 17 has a feed end in feed zone A adapted to receive the cut crop from feed conveyor 6. In order to transport the cut crop into the thresher, the feed end of rotor 21 comprises a tapered surface 22 with a curved profile or helix 23 formed on said surface. In order to create a impact action for the cut crop and simultaneously to allow the separated straw to be discharged from the straw discharge end 24, a helix 25 is provided on rotor 17 with a plurality of spaced fingers 20. Though fig.2 illustrates helix 25 as being provided along the entire length of rotor 17, in accordance with another embodiment helix 25 may be provided only in the separation or threshing zone C. Stator 21 has also a helix along the entire length except in the feed zone A having chute 7. In order to separate the grain from the straw, a concave plate 8 is provided in threshing zoneC. Reference is made to figs. 3a to 3c which illustrates the concave plate 8. Concave plate 8 comprises a frame 8a having a choke window 8b. in figs. 3a to 3c, the concave plate 8 is intended for an impact action and comprises equally spaced radial fingers or spikes 8c and which project outwardly of the surface of concave plate 8. Concave plate 8 has a leading section 8d and a trailing section 8e, the choke window 8b being provided in the trailing section 8e. A pivotal pin 8f is provided between the trailing section 8e and leading section 8d. As shown in fig.2 the clearance P at the leading section, which is the crop entry section, is more than that at trailing section 8e, which is the crop discharge side. After the threshing action in zone C, the grain is separated from the straw, which is facilitated by concave plate 8. After separation is effected in zone C, the grain falls in grain collection zone 27. Grain collection zone 27 has a known construction, namely that of a stepped bed 10, hinged screen 14, adjustable sieve 13 and screw conveyor 11. The grain is fed to a grain tank 18 through a grain elevator 12. A discharge anger is provided in tank 18. In accordance with this invention, and as illustrated in fig. 2, rotor 17 is disposed along the longitudinal axis of the thresher. A separating cage 16 comprises the lower section of stator21. The separated straw is discharged through discharge end 24. Reference is now made to the harvester combine having the thresher of the present invention. The thresher of fig.4 is identical to that of fig.2, and for this purpose like reference numerals denote like parts as those of fig.2. However, the thresher of fig.4 is intended to a standing crop such as wheat or maize and where a rubbing action is required on the crops rather than an impact action as provided by the construction of fig.2. For the purposes of brevity, only the difference in the construction of the thresher of fig.4 is described herein, the remaining features being identical to those as provided in fig.2. The rotor 17 no longer has a helix as provided in fig.2. However, rotor 17 has a plurality of rasp bars 21 in the threshing zone B which causes a rubbing action to a cut crop with stator 22 and a plurality of pegs 21 in the straw collection zone. Further, concave plate 8 has flats of a wire mesh construction equally spaced along the Y axis. The drawings illustrate the thresher in a harvester combine. As the invention does not reside in the harvester combine but in the thresher, such a thresher may be provided by itself or in any other agricultural apparatus. CLAIMS: 1. A thresher comprising a stator disposed along the longitudinal axis of the thresher, a rotor within said stator and also disposed along the longitudinal axis, said stator having a feed zone for receiving the standing crop, said stator having a threshing zone also disposed along the longitudinal axis, a concave disposed in said threshing zone and bdbw of said rotor, a collection zone for receiving the grains from said concave, a straw discharge zone having a discharge outlet at an end of said thresher opposite to the feed zone. 2. A thresher as claimed in claim 1 wherein said stator comprises a tubular member with a helix provided on the upper inner surface. 3. A thresher as claimed in claims 1 and 2 wherein said rotor is provided in a rotatable and spaced relationship within said stator. 4. A thresher as claimed in claims 1 to 3 wherein said rotor is tapered in the feed zone, a helix provided on said tapered surface. 5. A thresher as claimed in claims 1 to 4 wherein said rotor has a helix at least at tie separation zone, a plurality of fingers provided on the rotor. 6. A thresher as claimed in claim 5 wherein said lingers are disposed in a spaced relationship on said rotor. 7. A thresher as claimed in claim 5 wherein said helix is provided along the entire length of tiie rotor. 8. A thresher as claimed in claims 1 to 4 comprising a plurality of rasp bars provided on the rotor in the separation zone 9. A thresher as claimed in claims 1 to 4 comprising a plurality of pegs provided on said rotor. 10. A thresher as claimed in claims 1 to 4 wherein said concave plate comprises a trailing and leading end, the leading end being the crop entry and the trailing end being the crop discharge end, the leading end having a space from said rotor more than that of the trailing end. 11. A thresher as claimed in ctaim 10 wherein said concave has a choke of window with the trailing edge. 12 A thresher as claimed in claim 10 wherein said concave has a plurality of radial fingers or spikes 13 A thresher as claimed ift claim 10 wherein said concave plate comprises a wire mesh. 14 A thresher substantialiy as herein described and illustrated

Documents:

1027-del-2002-claims.pdf

1027-del-2002-correspondence-others.pdf

1027-del-2002-description (complete).pdf

1027-del-2002-drawings.pdf

1027-del-2002-form-1.pdf

1027-del-2002-form-18.pdf

1027-del-2002-form-2.pdf

1027-del-2002-form-3.pdf

1027-del-2002-form-4.pdf

1027-del-2002-form-5.pdf

1027-del-2002-gpa.pdf