US2718967A

US2718967A - Grain cleaner and separator

Info

Publication number: US2718967A
Application number: US270048A
Authority: US
Inventors: Herbert T Potter
Original assignee: Individual
Current assignee: Individual
Priority date: 1952-02-05
Filing date: 1952-02-05
Publication date: 1955-09-27
Anticipated expiration: 1972-09-27

Description

Sept. 27, 195-5 H. T. POTTER 2,718,967

GRAIN CLEANER AND SEPA'RATOR Filed Feb. 5, 1952 2 Sheets-Sheet 1 Sept. 27, 1955 H. T. POTTER 2,713,967

GRAIN CLEANER AND SEPARATOR Filed Feb. 5, 1952 2 Sheets-Sheet 2 0 6 (.J I 5 T F T m f T M 0 AL n M QVIQW/MVV w .il n UFIIU-YQQQ H nited States Patent GRAIN CLEANER AND SEPARAT OR Herbert T. Potter, Leonardsburg, ()hio, assignor of onefourth to Donald R. Potter, Leonardsburg, Ohio Application February 5, 1952, Serial No. 270,048

13 Claims. (Cl. 209261) Grain that is harvested by combine usually has more or less green weeds, grass, etc. mixed with it. Unless this moisture laden refuse is separatedfrom the grain it lowers the grade of the grain and is a frequent cause of spoilage of the grain while in storage.

It is important therefore that the combine grain cleaner operate at maximum efiiciency at all times. As now made, combine cleaners attain high efficiency only while they are operating over smooth, level ground, and in still air which conditions almost never exist over an entire field.

Combine cleaners usually use a shaking or vibrating screen over which the mixture of grain and refuse is passed toward the rear of the cleaner, while at the same time air from the cleaner fan is blown up through the screen, thus lifting and carrying out the refuse while the grain drops through the screen to be saved. For best results the air pressure under the screen must so match the thickness and air resistance of the layer of grain on the screen that it falls just short of blowing grain away along with the refuse.

Now when the cleaner is tipped in any direction from a level position, the layer of grain and refuse on the screen is changed with the following results.

Tipped sidewise the layer becomes thicker on the low and thinner on the high side of the screen. Because the air pressure is not changed it is now unable properly to pass through the thicker layer of grain on the low side, thus allowing refuse to remain with the grain while at the same time the thinner layer on the high side offers less than normal resistance to the air and is blown over with the refuse and wasted. When the rear of the cleaner is lowered, the layer of grain and refuse on the screen is, by being moved faster, made thinner. This layer then offers less resistance to the air passing through it so that grain is blown out with the chaff or refuse.

When the rear is raised above a level position the opposite action occurs. The layer becomes thicker making it impossible for the same air pressure to pass through it with enough force to remove the refuse from the grain.

Wind blowing against the machine as it moves around the field lowers its efliciency. Blowing against the air current which carries the chaff or refuse out of the cleaner, it, according to its velocity, neutralizes the air current inthe cleaner. Consequently, refuse is left in the grain. Blowing into an air inlet of the cleaner fan it not only increases the amount of air entering that side, but sets up uneven air pressure in the cleaner, lowering its efficiency.

An object of my invention is to provide a combine grain cleaner in which the above mentioned misfunctioning due to the tilting of the screen and to variable wind conditions is partly or fully avoided.

More specifically, an object of my invention is to provide a grain cleaner having a conventional screen and blower with means subject to manual or automatic or partly manual and partly automatic control for varying the supply of air to the screen to compensate for varia- 'ice tions in the depth of the layer of grain on the screen due to tilting.

A further object of my invention is to provide means operable in response to wind velocity and direction to vary the supply of air to the screen in such away as to neutralize the effect of wind on said air supply.

An illustrative embodiment of the invention is shown in the accompanying drawings in which:

Fig. 1 is a side elevation of a combine grain cleaner in accordance with my invention with the chassis omitted;

Fig. 2 is a side elevation similar to Fig. 1 but with the side wall and the parts in front thereof removed to reveal the interior of the screen chamber;

Fig. 3 is a top view of the rear part of the screen chamber with the top wall and the screen removed;

Fig. 4 is an axonometric view of the operating mechanism with the screen and screen chamber walls removed;

Fig. 5 is an enlarged view of one of the manually operable adjusting levers and its quadrant; and

Fig. 6 is a fragmentary perspective view of the fan and its housing showing the means for controlling the inlet of air thereto in accordance with the wind velocity.

It is noted that the grain cleaner normally is an integrai part of a combine comprising in addition to the cleaner means for cutting the grain, means for conveying the cut grain to threshing means, means for disposing of the separated straw, means for disposing of the cleaned grain and means for disposing of material of large size which did not pass through the cleaner screen. Since my invention resides only in a cleaner which may be used as a separate unit to which grain from a thresher may be delivered or as an integral part of a combine I have illustrated it separately.

The grain cleaner comprises the blower A and the wind tunnel B. The blower A is conventional and as illustrated consists of the fan 1 rotatable within the cylindrical housing 2 having a circular air inlet opening 3 at each end. The means for driving the blower is conventional and is not illustrated.

The wind tunnel B is rectangular in cross-section and communicates with the blower at its front end and with the atmosphere at its rear end. Suitably mounted within the wind tunnel B is the screen 4 which is substantially flat and slopes downwardly and rearwardly at a suitable angle for operation when the cleaner is horizontal.

To the above described conventional apparatus I have added, for the purpose of controlling the fiow of air through the screen, the three movable baffle plates 5, 6 and 7, the damper plate 8 and the wind vane 9 with means for operating the same to be more fully described below.

The baflle plate 6 is mounted vertically and pivotally on the shaft 10 at the longitudinal axis of the tunnel and at a point preferably at a substantial distance from the front end of the plate 6. The purpose of the plate 6 is to vary the division of the stream of air delivered by the blower between the two sides of the screen, i. e. to deliver more air and at a higher pressure or velocity to the low side of the screen where the grain is deepest and to deliver less air and at a lower pressure or velocity to the high side of the screen where the grain is thinnest. Thus when the plate 6 pivots about the shaft 10, its front end moves to one side thereby reducing the portion of air passing to one side of the screen and equally increasing the portion passing to the other side. At the same time the rear end of the plate moves in the opposite direction thereby spreading the smaller portion of air over a larger area of the screen and confining the larger portion of air to a smaller area of the screen. Mechanism to be described below automatically moves, the plate 6, with tilting of the machine about its longitudinal axis, so that its rear end moves toward the lower side of the screen.

The bafile plate 5 is mounted at the front end of the wind tunnel and serves to control the amount and disfribution of air from the blower to the tunnel." It is pivotally mounted by means of the stub shaft 11 and collar 12 adjacent the center thereof on the cross shaft 13. Rotation of the shaft 13 raises and lowers the plate 5 and thus varies the amount of air permitted to flow from the blower A to the lower side of the screen. Limited vertical movement of the plate 5 by rotation of the shaft 13 may be provided for in various ways as by merely providing an opening in the plate 5which is larger than the stub shaft 11 and permits the shaft 11 to tilt or by providing a ball and socket joint in the shaft 11 or by providing a cam on the shaft 13 where it passes through the collar 12. The vertical movement of plate 5 is subject to both manual and automatic adjustment as will appear hereinafter.

The lower edge of plate 5 is V-shaped and normally permits equal amounts of air to pass thereunder to the two sides of the screen but may be tilted about the pivot point provided by the shaft 11 to partially close the passageway on one side and correspondingly enlarge the passageway on'the other side. This tilting movement is effected automatically by the rod 14 pivotally attached at the middle of the upper edge of the plate by the projection 15, hub 16 and pin 17. This tilting of the plate 5 is entirely automatic and serves to deliver more air to the low side of the screen and less air to the high side as will appear hereinafter.

The baffie plate 7 at the rear end of the wind tunnel is carried on the cross shaft 18 by means of two stub shafts 19 and collars 20 similar to the stub shaft 11 and collar 12 and are similarly provided with means (not shown) permitting a vertical movement of the plate 7 with rotary movement of the shaft 18. Plate 7 is subject to both manual adjustment and automatic control as will appear hereinafter. Plates 6 and 7 are omitted from Fig. 4.

For controlling the vertical movements of the plates 5 and 7 their respective supporting

shafts

13 and 18 are secured to the hubs 21 and 22 for rotation therewith. Hub 21 carries the notched quadrant 23 and hub 22 carries the notched quadrant 24. Hub 21 carries also the normally vertically disposed shaft 25'which carries the weight 26 on its lower end and the hub 27 on its upper end. Hub 22 carries the normally vertically disposed shaft 28 which in turn carries the hub 29 on its lower end and the wind vane 9 on its upper end. Hubs 27 and 29 are connected by means of the rod 31. As will be seen, when the grain cleaner tilts on its transverse axis, i. e. when its front end is lowered or raised with respect to its rear end, the weight 26, by its tendency to maintain its lowermost position will hold the shaft 25 in vertical position and thus will rotate the

shafts

13 and 18 with respect to the plates 5 and 7 and thereby raise one of them and lower the other with respect to the wind tunnel. Specifically, if the front end of the machine is lowered with respect to the rear end grain will tend to pile up on the screen to a greater depth requiring a greater pressure of air to penetrate the layer and carry off the refuse and additional air will be admitted by the plate 5 being raised by the rotary movement of the shaft 13 effected by the movement of the weight 26 relative to the machine. At the same time plate 7 will be lowered to permit discharge of the greater quantity of air from the wind tunnel. When the machine tilts in the opposite direction so that its front end is higher and its rear end lower and the grain moves more swiftly over the screen and in a thinner layer plate 5 is lowered and plate 7 raised by relative movement of the weight 26 to reduce the flow of air through the screen.

Plate 7 not only cooperates with plate 5 to control the amount of air flowing through the wind tunnel but it also serves as a baffle to intercept and save grain picked up by the air current. Thus when the machine is tilted with its front end low there is little tendency for grain to be carried by the wind current and plate 7 therefore is in its lower position but when the front end of the machine is high and the grain flows swiftly and in a thin layer over the screen plate 7 is raised to intercept and save grain which tends, under these conditions, to be picked up and carried along by the wind current.

The manual adjustment of the plates 5 and 7 is effected by means of the

levers

33 and 34 which are rigidly attached to the

shafts

13 and 18 respectively and carry the

counterweights

35 and 36 which to some extent at least counterbalance the weights of the plates 5 and 7 and render their movement easier.

Levers

33 and 34 cooperate with the notched

quadrants

23 and 24 to hold the plates 5 and 7 in any desired manually adjusted positions.

Manual adjustment of the plates 5 and 7 may be desirable or necessary in order to secure optimum operation under varying conditions such as for instance the kind and size and condition of the grain being harvested, the character of the refuse, the moisture content of the grain and refuse, etc. It may be necessary to manually adjust the plates 5 and 7 only once for a given harvesting operation or it may be necessary to manually adjust the plates 5 and 7 as the moisture condition of the grain and refuse vary from morning to evening or as the character of the grain and refuse vary in different parts of a field of grain.

The wind vane 9 provides an additional automatic control of the plates 5 and 7 to compensate for variations in wind direction and velocity. A strong wind blowing from the front toward the rear of the machine tends to increase the flow of air through the wind tunnel and this tendency is compensated by a rearward movement of the wind vane 9 resulting in raising the plate 7 and lowering the plate 5. Wind blowing in the opposite direction, i. e. from the rear toward the front of the machine tends to reduce the current of air in the wind tunnel and is compensated by 'a forward movement of the vane 9 which lowers the plate 7 and raises the plate 5.

The movement of the plates 5 and 6 to compensate for lateral tilting of the machine is controlled by the weight 37 carried on the shaft 38 which is supported and pivotally attached to the bracket 39 by the hub 40 and pivot pin 41. Shaft 38 is pivoted to the shaft 14 by the hubs 42 and 43 and the pin 44. Shaft 38 is connected by the fork 45 to the shaft 46 which in turn (see Fig. 3) is connected to the plate 6. Weight 37 is free to swing in a plane perpendicular to the longitudinal axis of the machine and as the machine tilts from side to side weight 37, acting through the

shafts

38, 14 and 46, tilts the plate 5 and swings the plate 6 as described above to admit more air to the low side and less air to the high side of the wind tunnel.

As described above, the wind vane 9 operates through the plates 5 and 7 to control the flow of air through the wind tunnel and this ordinarily may be sufficient but it may be desirable under certain critical conditions such as in the case of a strong wind at right angles to the cleaner to control the supply of air to the blower. To this end I have provided, as illustrated in Fig. 6, automatic controls of the air inlets at each end of the blower A. Each control consists of the shutter 8 pivoted at 47 and adapted to swing over the inlet to the blower and partially close the same. Shutter 8 is connected through the rod 48 and lever 49 to the wind vane 50 which is swingably mounted on the bracket 51. A strong wind tending to blow into the air inlet to the blower strikes the vane 50 and swings it toward the wind tunnel thereby moving the shutter 8 over a portion of the air inlet. Thus the increased pressure of air at the inlet tending to supply more air to the blower is compensated by the decreased size of the opening.

30 are guides for the baffle plate 5. 32 and 32 are pans for delivering grain to the screen 4 and are shown in the position of pans situated to deliver grain from a thresher (not shown) located within the hood C. 52 and 53 are discharge screws respectively for the clean grain and heavy material that did not pass through the screen 4. 54 is the outlet from the tunnel B for air and chaff.

It is to be understood that the invention is not limited to the mechanical details of the embodiment of the invention illustrated and described herein by way of illustration excepting as may be required by the appended claims. It is fully appreciated that the many changes in mechanical details and even additions thereto may be made without departing from the spirit and general principles of my invention.

I wish it to be understood further that the invention is not limited to the use in combination of all of the controls illustrated and described excepting as may be required by the terms of the appended claims. I may, for instance, omit the shutter 8 and its controls and the wind vane 9 or either of them and I might even omit the manual controls provided by the

levers

33 and 34 and the parts associated therewith.

I claim:

1. In combination with a mobile grain cleaner comprising a blower, a wind tunnel connected to said blower and a screen positioned in said wind tunnel, a baflle positioned in the path of the stream of air flowing from said blower to said wind tunnel and means for automatically rotating said baffle about an axis perpendicular to the plane thereof in response to tilting of the cleaner about its longitudinal axis.

2. The combination as defined in claim 1 comprising means for automatically raising and lowering said baffle in response to tilting of the cleaner about its transverse axis.

3. The combination defined in claim 2 comprising means for manually raising and lowering said battle.

4. The combination as defined in claim 3 comprising means responsive to air currents moving longitudinally of the cleaner, externally thereof, for raising and lowering said bafiie.

5. In combination with a mobile grain cleaner comprising a blower, a Wind tunnel connected to said blower and a screen positioned in said wind tunnel, a normally vertically disposed baffie positioned in said wind tunnel, said baffle being pivotally supported to rotate about a normally vertical axis positioned adjacent the longitudinal axis of said tunnel at a point with respect to said bafile within the front half thereof and at a substantial distance from the front end thereof and means responsive to tilting of said cleaner about its longitudinal axis to turn said bafiie about said axis.

6. The combination as defined in claim 5 in which said baflle normally extends longitudinally of said wind tunnel and comprising also a baffle extending transversely of said wind tunnel, said means for turning said longitudinally extending bafile serving also to turn said transversely extending baffle about an axis perpendicular thereto.

7. In combination with a mobile grain cleaner comprising a blower, a wind tunnel connected to said blower and a screen positioned in said wind tunnel, a battle positioned in the path of the stream of air flowing from said blower to said wind tunnel, a second bafile positioned adjacent the rear end of said wind tunnel, manual means for separately and independently raising and lowering each of said bafiles to control the flow of air through said tunnel and automatic means responsive to tilting of the cleaner about its transverse axis for simultaneously moving said bafiles in opposite directions.

8. The combination defined in claim 7 comprising means responsive to wind currents external to said tunnel for simultaneously moving said baflies in opposite directions.

9. In combination with a mobile grain cleaner comprising a blower, a wind tunnel connected to said blower and a screen positioned in said tunnel, a bafile positioned transversely of said tunnel adjacent the front end thereof, a second baflle positioned normally, substantially vertically and in the middle longitudinal axis of said tunnel and being mounted to rotate about a vertical axis positioned in the front half of said baffie but at a substantial distance from the front end thereof, means responsive to tilting of said cleaner about its transverse axis for raising and lowering the first named batfie and means responsive to tilting of the cleaner about its longitudinal axis for simultaneously rotating the first named baffle about an axis perpendicular thereto and rotating the second named baffie about said vertical axis.

10. In combination with a mobile grain cleaner comprising a blower having an air inlet, a horizontally disposed wind tunnel connected at one end to said blower and a screen positioned within and adjacent the upper wall of said wind tunnel, a first bafile positioned normally vertically adjacent the front end of said wind tunnel, said first bafiie being rotatably supported on a horizontal axis, a second baffie positioned normally vertically and in the middle longitudinal axis of said wind tunnel, said second baffle being mounted to turn about an axis positioned in the front half thereof but at a substantial distance from the front end thereof, a third baffle positioned normally vertically and adjacent the rear end of said wind tunnel, means for separately and independently manually raising and lowering each of said first and third baffles, means responsive to the tilting of the cleaner about its transverse axis for automatically and simultaneously moving said first and third bafiles vertically in opposite directions, and means responsive to tilting of said cleaner about its longitudinal axis for simultaneously and automatically rotating said first baflle about its horizontal axis and rotating said second baflle about its vertical axis.

11. In combination with a mobile grain cleaner comprising a blower, a Wind tunnel connected at one end thereof to said blower and a screen positioned in said wind tunnel, a bafile positioned in said wind tunnel adjacent the other end thereof, means for moving said baffle to vary the flow of air through said tunnel, means actuated by the tilting of the cleaner about its transverse axis and connected to actuate said means for moving said bafile and a baffle in said wind tunnel adjacent the front end thereof and means connecting the two baflles whereby said bafiles are automatically moved in opposite directions.

12. The combination as defined in claim 10 including means responsive to wind currents external to said cleaner for automatically and simultaneously moving said first and third bafiles vertically in opposite directions.

13. The combination as defined in claim 10 including means responsive to wind currents external to said blower for automatically varying the size of the air inlet thereto.

References Cited in the file of this patent UNITED STATES PATENTS 449,743 Lan-dis Apr. 7, 1891 509,082 Heald Nov. 21, 1893 620,358 Reeves & Kailor Feb. 28, 1899 885,215 Amer Apr. 21, 1908 1,122,803 Rhodes Dec. 29, 1914 1,230,437 Schuette June 19, 1917 1,922,986 Stith Aug. 15, 1933 2,189,706 Clipston Feb. 6, 1940 2,611,487 Stevenson Sept. 23, 1952