CA1108104A - Feed mill - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE

A feed mill is shown for chopping and crushing grain, such as corn, for the production of animal feed or fodder. The feed mill has an input hopper defining a lon-gitudinal outlet opening. An elongate rotatable cutter assembly is located in the hopper adjacent to the hopper outlet for chopping and feeding the grain therethrough.
A pair of adjacent, parallel, rotatable crushing rolls defining a nip are located below the hopper outlet. The crushing rolls have cylindrical surfaces defining pyramid shape indentations arranged in a diamond pattern and sur-rounded by protuberant cutting edges. Drive means are coupled to the cutter assembly and the crushing rolls for rotating same. The crushing rolls are rotated in opposite directions so that grain from the hopper outlet enters the nip to be crushed and passed through the crushing rolls. A conveyor removes the crushed grain from below the crushing rolls.
The crushing rolls include a driving roll, and a driven roll, the latter roll being driven by frictional contact between the adjacent surfaces of the respective rolls.

Description

`` 1~08104 The present invention relates to feed mills for chopping and crushing various types of grain for the production of animal feed. In particular, the present invention relates to feed mills of the type having parallel, adjacent rollers between which the grain is passed to be reduced to feed.
In the production of animal feed, various types of grain are harvested and usually stored in silos for use over a period of time as required. Almost any type of grain may be used for this purpose, some of the more common types being corn, barley, wheat and rye. It is even possible that some other types of vegetables may be used to produce feed, and for this reason, the term grain as used in the present specification will include all types of grains or vegetables that are usually used for animal feed.
Before the grain can be stored or fed to the animals, it is usually necessary to process the grain through a feed mill to reduce the grain to an edible consistency and increase its nutrient value for the animal. For example, in order to feed corn to animals, it is usually necessary to chop and crush the cobs of corn before the animal can eat and properly digest the corn. However, the manner in which ; the grain kernels are crushed has an important bearing on the nutrient value or digestion of the kernels by the animal. If the kernels are crushed or broken too much, the grain will pass through an animal's digestive system too fast and the animal will not be able to obtain all of the nutrient value from the grain. If the kernels are not crushed enough, the animal may not be able to digest same . ~

`" 11~)8104 at all, resulting in no nutrient value being obtained from the grain.
In the feed mills produced in the past, parallel rolls have been used to crush or break the grain by passing the grain between the rolls. Usually, the rolls have longitudinal or helical grooves to help feed the material through the rolls, and sometimes the rolls are rotated at different speeds to produce a grinding or shearing action on the grain. A difficulty with these prior art feed mills is that the grain is often chopped, torn or shredded too much, or a substantial amount of whole grain kernels passes right through the rollers without being crushed at all.
This excessive chopping or crushing results in the undesir-able production of flour, or dough in the case of grains with high moisture content. Further, this dough often fills the grooves in the rolls so that the grain stops - passing through the rolls.
In the present invention, the grain kernels are cracked or broken in several places and the kernels are only partially crushed. This facilitates digestion by the animals so that the animals get the full nutrient value from the grain. In addition, it also produces a softer kernel, so that the grain compacts better in storage with less entrapped air to cause undesirable fermentation.
In the present invention, parallel crushing rollers are provided with cylindrical surfaces that define indenta-tions arranged in a diamond pattern, whereby the crushing rollers partially crush and soften the grain kernels as desired.
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~ ~ - 3 -According to the present invention, there is pro-vided a feed mill for chopping and crushing grain. The feed - mill comprises a housing having a hopper for the introduction of grain into the feed mill. The hopper defines a longitudinal outlet opening. An elongate rotatable cutter assembly is located in the hopper adjacent to the hopper outlet, the cutter assembly having a plurality of paddles for chopping and feeding the grain through the hopper outlet. A pair of adjacent, parallel, rotatable crushing rolls are located in the housing. The crushing rolls define a nip located below the hopper outlet and the crushing rolls have cylindrical sur-faces defining pyramid shape indentations arranged in a diamond pattern and surrounded by protuberant cutting edges. Drive means are coupled to the cutter assembly and the crushing rolls for ro-tating same, the crushing rolls being rotated in opposite direc-tions, so that grain entering the nip is crushed and passed through the crushing rolls. Also, conveyor means is located below the crushing rolls for removing the crushed grain from the feed mill.
A preferred e~odiment of the invention will now be described, by way of example, with reference to the accompanying drawings, in which:
Fig. 1 is a perspective view, partly broken away, of a preferred embodiment of a feed mill according to the present invention;
Fig. 2 is a plan view of the crushing rolls used in the embodiment shown in Fig. l;
Figs. 2a and 2b are detail views of part of Fig. 2;
Fig. 3 is a diagrammatic, side elevational view taken along lines 3-3 of Fig. l;

,. : ' Fig. 4 is a diagrammatic perspective view similar to Fig. 1, with the hopper and crushing rolls removed; and Fig. 5 is an enlarged parti~l sectional view of a preservative metering valve as used in the embodiment shown in Fig~ 4.
Referring to the drawings, a preferred embodiment of a feed mill according to the present invention is gener-ally indicated by reference numeral 10. Feed mill 10 includes a frame or housing 12 having an upper, generally funnel-shaped hopper 14 for the introduction of grain into the feed mill. As seen best in Fig. 3, hopper 14 has a longitudinal outlet opening 16 extending across the width of the hopper. An elongate, laterally slidable feed gate 18 is adapted to close hopper outlet 16 to control the rate of pas-sage of grain out of hopper 14. The position of feed gate 18 is controlled by a crank 20 having a threaded end portion 22 threadably engaging a block 24 attached to the midsection of feed gate 18. Crank 20 is longitudinally restrained by a bear-ing block 26, so that rotation of crank 20 causes feed gate 18 to slide laterally to open and close hopper outlet opening 16.
An elongate rotatable cutter assembly 28 (see Fig.3) is located in the hopper adjacent to hopper outlet 16.
Cutter assembly 28 includes radially extending, elongate paddles 30, two of which include elongate cutting blades 32.
Upon rotation of cutter assembly 28, the cutting blades chop any large pieces of the grain, such as corn cobs, and the paddles feed the grain through hopper outlet 16. It will be appreciated that the sides of hopper 14 adjacent to cutting blades 32 will be made sufficiently strong to withstand the ~; ~ 5 -chopping action which occurs as cutter assembly 28 rotates.
A pair of adjacent, parallel, rotatable crushing rolls 34, 36 are located in housing 12 in line with hopper outlet 16. Crushing rolls 34, 36 define a nip 38 which is located below hopper outlet opening 16 to receive the chopped grain emerging or being fed from the hopper to the crushing rolls.
Crushing roll 34 is a driving roll, and for this purpose has a central axial drive shaft 40 (see Fig. 1).
Shaft 40 has a splined end portion 42 which is adapted to be coupled to any convenient drive means, such as an electric motor or a tractor power take-off. Driving roll 34 is mounted in housing 12 using suitable bearing blocks (not shown).
Driving crushing roll 34 includes a pair of longitudinally spaced-apart, resilient, O-ring bands 44 located adjacent to respective ends of driving roll 34 (see Fig. 2). The surface of roll 34 defines circumferential, concentric, U-shaped grooves (not shown) for seating or accommodating O-ring bands 44, and the bands are attached to the surface of driving roll 34 in any convenient manner to prevent relative rotation between bands 44 and driving roll 34.
As seen best in Fig. 2, bands 44 radially project above the surface of roll 34 to engage and frictionally drive crushing roll 36. These bands project above the crushing roll sur-face approximately 4 millimeters, so that nip 38 typically may be adjusted in width between 0.2 and 1 millimeter, as described further below.

~ 8104 Crushing roll 36 is a driven roll, being driven by frictional engayement with the resilient O-ring bands 44 of driving roll 34. Driven roll 36 is rotatably mounted in a frame 46 using conventional bearing blocks (not shown).
Frame 46 is pivotally mounted in housing 12 by pivot pins 48 attached thereto, which pins are in turn retained by suit-able bearing blocks 50. It will be appreciated from Fig. 3, that as frame 46 is pivoted in the direction of arrow 52, the width of nip 38, or the distance between crushing rolls 34, 36 is varied. However, during the normal operation of feed mill 10, the surface of driven roll 36 remains in frictional contact with the surface of driving roll 34, because O-ring bands 44 are resilient and deform to accom-modate differences in the width of nip 38.
The width of nip 38 is adjusted by adjustment means coupled between the housing 12 and driven roll 36.
This adjustment means includes a fine adjuster 54 (see Fig. 1) in the form of a bolt threadably attached to frame 46 to bear against a suitable wall portion 56 of housing 12. The adjustment means also includes a quick-release cam 58, which has an upper portion 60 attached to a cross bar 62 of frame 46, and a lower portion 64 attached to a handle 66. Lower portion 64 is rotatably mounted on a leaf spring 68, which in turn is attached to housing 12. As will be apparent to those skilled in the art, the quick-release cam upper and lower portions 60,64 define cam surfaces such that rotation of handle 66 causes a relatively rapid change in the vertical distance between cross bar 62 and leaf spring 68. Quick-release cam 58 is normally maintained in the fully extended 810~

position, but in the event that something should enter the crushing roll nip to jam or block these rolls, handle 66 can be ~uickly rotated to disengage or separate the crushing rolls to release any foreign object or blockage. It will also be appreciated that leaf spring 68 biases the driven crushing roll 36 into engagement with the driving roll 34 by tending to cause frame 46 to rotate clockwise as shown in Figs. 1 and 3.
The driving and driven crushing rolls 34, 36 have cylindrical surfaces defining indentations 70 arranged in a diamond pattern. Indentations 70 are arranged in a regular pattern of intersecting, generally helical rows to form this diamond pattern. In Fig. 2, the rows are indicated by lines on the surfaces of the rolls.
Fig. 2a shows four of the indentations 70 and it will be seen that each indentation is generally of inverted pyramid ~- shape. The indentations are spaced longitudinally along the said helical rows by approximately 8 millimeters, and the rows themselves are spaced from one another by approxi-mately 8 millimeters. Indentations 70 are approximately

2 millimeters square at the surfaces of the rolls 34 and 36 and are between 2 and 5 millimeters in depth. It is to be understood that the above dimensions are given by way of example only and may vary, for example, depending on grain size. Each of the indentations 70 is formed by driving an appropriately shaped punch into the relevant surface, which causes localized upward deformation of material around the indentation, producing sharp edges which cut into the grain when the feed mill is in operation. Fig. 2b is a vertical sectional view through one of the indentations 70 and shows . , ~1~)8104 the deformations at 71 and the sharp upwardly directed edges at 71a.
Crushing rolls 34, 36 and cutter assembly 28 are rotated or driven from drive shaft 40 using suitable sheaves 72 and V-belts 74 in a conventional manner. It will be appreciated that because of the frictional eng ge ment of the driving and driven crushing rolls, these rolls are rotated in opposite directions, so that the grain entering nip 38 is crushed between and passed through these 10 rolls. Crushing rolls 34, 36 rotate at generally the same peripheral speed, there being a very slight difference in view of -the thickness of O-ring bands 44. However, ln view ` of the compression or deformation of bands 44 in operation, the difference in rotational speed between the crushing rolls is negligible.
- Referring to Figs. 4 and 5, housing 12 includes a bottom tray portion 76 having a concave or V-shaped bottom surface 78 for collecting the crushed grain. A screw conveyor 80, which is also driven from drive shaft 40, 20 collects and removes the crushed grain from tray portion 76. A vertical elevator conveyor 82 receives the crushed grain from screw conveyor 80 and raises the crushed grain for subsequent delivery ultimately to storage.
An optional preservative tank 84 is shown in Fig.
4 for adding conventional preservative chemicals to the crushed grain. Such chemicals are typically used to acidify the crushed grain to remove oxygen by causing substancially uniform fermentation to take place throughout the grain until all the oxygen in the grain has been consumed; re-g _ .

~8104 moval of oxygen in this way prevents spontaneous localisedfermentation which would result in deterioration of the grain in storage. A metering conduit 86 communicates with preservative tank 84 for adding the preservatives to the crushed grain. Metering conduit 86 includes a metering valve 88 for constricting the conduit and controlling the flow of preservatives therethrough.
In operation, the grain to be crushed is fed into the top of hopper 14 where it is chopped by cutter assembly 28, if necessary. The cutter assembly prevents voids from forming in the grain which otherwise would adversely affect the flow of grain out of the hopper. The cutter assembly therefore positively feeds the grain down through hopper outlet opening 16 and into nip 38 of the crushing rolls.
Feed gate 18 is adjusted, depending upon the type of grain being crushed, to maintain an even flow of chopped grain which will not overload the crushing rolls. It will be appreciated that it requires more power to turn the crushing rolls for higher rates of feed, and therefore the rate of feed is adjusted commensurate with the power input being supplied to drive shaft 40. The nip of the crushing rolls 34, 36 is adjusted using fine adjuster 54 depending upon the type of grain being crushed. As discussed above, it is desirable only to partially crush the grain kernels so as not to produce flour or dough by excessive crushing, and yet the nip must be kept narrow enough to ensure that all of the kernels are partially crushed. In the event that a foreign object, such as a rock, should enter nip 38, handl~
66 is rotated so that quick-release cam 58 disengages the ~1~)8104 crushing rolls and allows the foreign object to pass harm-lessly through the feed mill. Finally, as the grain is crushed, conveyors 80, 82 remove the grain from the feed mill for ultimate delivery.
Having described a preferred embodiment of the invention, it will be appreciated that various modifications may be made to the structure described. For example, feed mill 10 may be made in any convenient size, and suitable wheels or the like may be added to make the feed mill trans- `
portable for convenience. Although mild steel is used for the various components of feed mill 10, other materials, such as stainless steel or plastic, could be used for some of the components if desired. Of course, leaf spring 68 is made of spring steel, but other means may be used to bias the driven roll into engagement with the driving crushing roll. O-ring bands 44 are normally made of natural ! or synthetic rubber, but other plastic deformable material may be used if desired. Finally, other configurations may be used for the cutter assembly 28 to chop the grain entering the feed mill, and if the grain is of a consistency such that chopping is not required, cutter assembly 28 could be eliminated or disengaged.
By using the present invention, a superior quality feed is produced which is more nutritious for the animal, and which may be stored with less deterioration than the feed produced in the past using the prior art feed mills.

Claims (11)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A feed mill for chopping and crushing grain, the feed mill comprising: a housing defining a hopper for.
the introduction of grain into the feed mill, the hopper defining a longitudinal outlet opening; an elongate rotatable cutter assembly located in the hopper adjacent to said hopper outlet; the cutter assembly having a plur-ality of paddles for chopping and feeding the grain through said hopper outlet; a pair of adjacent, parallel, rotatable crushing rolls located in the housing, the crushing rolls defining a nip located below said hopper outlet, and the crushing rolls having cylindrical surfaces formed with inden-tations arranged in a regular diamond pattern of intersecting rows extending generally helically about said rolls, said indentations being of inverted generally pyramid shape and being surrounded by protuberant cutting edges; drive means coupled to said cutter assembly and said crushing rolls for rotating same, the crushing rolls being rotated in opposite directions, so that grain entering said nip is crushed and passed through said crushing rolls; and conveyor means located below said crushing rolls for removing the crushed grain from the feed mill.

2. A feed mill as claimed in claim 1 wherein said drive means rotates the crushing rolls at generally the same peripheral speed.

3. A feed mill as claimed in claim 2, wherein one of said pair of crushing rolls is a driving roll and is coupled to said drive means, and wherein the other of said crushing rolls is a driven roll, the surface of said driven roll being in frictional contact with the surface of said driving roll, so that the driven roll is rotated by the driving roll.

4. A feed mill as claimed in claim 3 wherein the driving roll includes a resilient, concentric band attached to the surface of the driving roll to engage and friction-ally drive the driven roll.

5. A feed mill as claimed in claim 4 wherein said band is one of a pair of longitudinally spaced-apart bands, said bands being located adjacent to respective ends of the driving roll.

6. A feed mill as claimed in claim 5, wherein said bands are in the form of O-rings, the driving roll surface defining circumferential grooves for seating said O-ring bands.

7. A feed mill as claimed in claim 1, wherein the hopper further includes an elongate, laterally slidable feed gate adapted to close said hopper outlet for control-ling the rate of feeding of the grain to the crushing rolls.

8. A feed mill as claimed in claim 4, wherein the driven roll is biased into engagement with the driving roll.

9. A feed mill as claimed in claim 8 and further comprising adjustment means operatively coupled between the housing and the driven roll for laterally adjusting the position of the driven roll relative to the driving roll and thus the width of said nip between the driven and driving rolls.

10. A feed mill as claimed in claim 9, wherein said adjustment means includes a quick-release cam for rapid separation of the driven and driving rolls.

11. A feed mill as claimed in claim 1 further comprising a preservative tank attached to the housing, and a metering conduit communicating with said tank for adding preservatives contained therein to the crushed grain.