US336567A - Fan for grain-separators - Google Patents

Description

(No Model.)

J. HAWK.

FAN FOR GRAIN SEPARATORSQ No. 336,567. Patented Feb. 23, 1886.

' WITNESSES M M I/VVEIVTOR NTTED STATES PATENT OFFICE,

JACOB HAWK, OF CANTON, OHIO.

FAN FOR GRAIN-SEPARATORS.

fiPEGIPICATION forming part of Letters Patent No. 336,567, dated February 23, 1886.

Application filed Sept-ember 10, 1885. Serial No. 176,718. (No model.)

To all whom it may concern:

Be it known that I, JACOB HAWK, a citizen of the United States, and a resident of Canton, county of Stark, State of Ohio, have invented a new and useful Improvement in Fans for Grain-Separators, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, making part of this specification.

My invention relates to an improvement in grain-separators; and it consists in the combin'ation,with vibrating riddles, of a fan having a larger diameter at its middle section than at its ends.

In the accompanying drawings, Figure 1 is a side elevation of thrashing-machine with the side board removed, showing the working parts with my improvements attached. Fig. 2 is a View in perspective of the fan, and Fig. 3 is a detached View in perspective of one of the fan-blades.

a b c d efg represent the frame-work of the body of the machine. Aisthe vibrator, which may be constructed after any of the well-known plans, or it may consist of a series of notched boards arranged parallel to each other, and of such distance apart as may be best adapted to carry the straw out of the machine, the grain falling through the vibrating table to a return-board, thence to the riddles in the usual Way.

The winnowing apparatus is constructed as follows: A, Fig. 1, represents the fan or winnowing wheel, B the vibrating riddle-snpporting shoe, C G the wire screens or riddles, and D D spouts by which the thrashed grain is conducted to the riddles.

The shoe B may be supported and vibrated by any of the well-known and approved plans, and the riddles such as are usually provided for such machines, as my invention relates particularly to the construction of the fan and its relation to the shoe and riddles.

Vith the winnowing-fans having the same diameter throughout their entire lcngth,it has been difficult, if not impossible, to" obtain a proper distribution of wind-blast over all arts of the riddles, being always weaker in the middle of the riddle, in proportion to the requirements,than at the sides,and if the speed of the fan be increased so as to properly chaff and clean the grain on the middle section. of

the riddle, the blast will be so strong at the sides that it will carry out large quantities of grain. There may be two reasons for this first, because there is more grain deposited on the middle section than on the end section of the riddle; second, because of the increased width of the modern separators.

To obtain a more perfect separation of the grain from the straw and chaff, the separating and winnowing parts of thrashing and separating machines have been made wider than the length of the thrashing-cylinder, to wit: A twenty-four-inch cylinder would have a thirty-four'inch separator, athirty-inch cylinder a forty-two-inch separator, a thirtythreeinch cylinder a forty-liveinch separator, and a thirty-siX-inch cylinder a forty-eight-inch separator. The length of the fan is always the full width of the inside of the separator; consequently the length is out of proportion to the diameter, and the result is the blast is liable to be the weakest from the center of the fan, where it should be the strongest.

The demand, in fact the necessity, for wide separators in which the straw may be so spread out as to secure a more perfect separation of the grain from the straw must be followed up with an increased length of fan, and the difficulties arising from this increased width of separator could not be overcome by increasing the diameter of the fan throughout its entire length.

All fans constructed in the ordinary manner, over two feet in length, placed inside the walls of a separator, throw off a greater blast at the ends than at its center. This is occasioned by the fact that the supply of air cannot reach the center of the fan when the latter is driven at a proper rate of speed.

In all thrashingmachines there is more grain thrashed in the middle of the machine than at the sides, and as a result more grain and chaff are deposited at or near the middle of the riddle. It follows that the additional amount of matter deposited at or near the center of the riddle requires a proportional increase of blast to thoroughly separate them; and to accomplish a thorough separation I provide a fan wheel which has alarger diameter through its middle section, from E to E, than through the end section, and should be in proportion to the width of the separator; but with an increased diam- ICO eter 0f the middle section of the fan the increased distance traveled by said enlarged section will cause an increased flow of air to the center of the middle sectiomand as a result an increased blast from the middle section.

To obtain a properly-proportioned Windblast over the riddle for a thirty-four-inch separator, the diameter of the middle section of the fan for about one-third its length should be two inches larger in diameter than at the ends, and fora forty-eight-i1ich separator the middle section should be about four inches larger in diameter than the ends, and they may be graded to suit the intermediate sizes. The average diameter of fan is twenty-four inches, average length of blade tl1irty-nine inches,and average breadth of central portion ofthe blade about seven inches.

In the construction of the fan I prefer to cut away the ends of the blades A", as shown in Figs. 2 and 3, reducing the end sections to a smaller diameter than the middle section. The middle section, being larger in diameter, will travel farther and faster than the end sections, and the result is the ejection of astronger blast of wind from the middle than the end sections.

Having fully described my invcntion,what I claim as new, and desire to secure by Letters Patent, is

In a grain thrashing and separating machine,the combination,with vibrating riddles, of a fan having a larger diameter atits middle section than at its ends, substantially as and for the purpose set forth.

In testimony whereof I have hereunto set 5 my hand this 8th day of September,A.D. 1885.

JACOB HAWK. Witnesses:

CHAS. R. MILLER, W. K. MILLER.

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