AU2007201565A1 - An Improved Roller Mill Apparatus - Google Patents

Description

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION Invention Title: Invetio Tile:An Improved Roller Mill Apparatus An Improved Roller Mill Apparatus.

Field of Invention: The present invention relates to roller mills. In particular the present invention relates to an improved apparatus for roller mill processing of grains but is not limited to such.

It is more particularly related to an improved apparatus construction and method of construction.

Background of the Invention: Roller mills using one or two rollers providing a frictional tearing are traditionally used for milling grain. The degree of milling depends on the end product required.

Grain may, for example, merely be crushed for stock feed. Another traditional end product of the milling process is flour for cooking purposes. Depending on the nature of the end product required, traditional methods have included multiple grinding passes followed by sifting out the hulls or outermost layer of the kernel.

A roller mill for grinding granular material generally comprises one or more pairs of contra-rotating rollers providing a gap between their cylindrical surfaces into which material to be ground is fed, and a feed delivery device located relative to the rollers to deliver feed material into the gap.

The pair of rollers may include corrugations or grooves or other surface material or surface cross-sectional profile to aid in the grinding process and particularly drawing the grain into the gap. As the profiles wear, they become less effective in drawing grains into the mill and require machining to restore the profile for further practical use. This is generally inconvenient since machining requires removing the ineffective roll, transporting the roller to a workshop and subsequently resurfacing the roller for return and re-assembly. While the roller mill is not in use, a farmer or grain producer is not generating an end product hence income is affected.

Generally, roller mills process harvested grain product in bulk quantity by means of a feed device or hopper having an opening positioned relative to the rollers to allow flow of grain into the gap. Delivery of material to the gap can be aided by generating pulses resulting from rotation of an eccentric mass thereby subjecting the feed delivery device to a vibratory motion. As a result of this vibratory motion, material in the feed delivery device is fed towards an exit to fall into the gap between a pair of rollers.

While advances in roller milling devices have been made to improve efficiency of feed delivery to the rollers, existing mill roll devices tend to crush or grind grain product. While this is desirable in one aspect, if a particular end product is desired, which cannot be achieved by crushing, existing devices have not been able to provide effective and practical alternatives. Further, it has been found that as grain producers increase their yield of grain over several seasons, to cater for increased crop production and processing, producers have had to expand by purchasing progressively larger machines with commensurately larger rollers. There is thus a need to provide a more effective way of catering for processing increasing production without the need and expense of purchasing a new roller mill machine.

It is therefore one object of the present invention to provide a mill roller device which addresses at least one of the prior art disadvantages.

It is a further object of the present invention to provide the public with a practical alternative mill roller, which can be adapted to cater for low to high yields of produce.

Yet a further object of the present invention is to provide a mill roller, which can provide an alternative process by tearing.

Summary of the Invention In accordance with the invention there is provided a roller mill having a modular elongated rectilinear skeletal framework housing wherein the housing has open sides to allow ready connection to modular input and output feeders and further including one or more motor mounting means for receiving and mounting one or more motors in a tirst compartment; and spaced mounting means attached to the elongated rectilinear skeletal framework housing and extending across the housing to form an adjacent second compartment for receiving and mounting one or more rollers in substantially parallel configuration and able to be connected to and driven by one or more motors mounted on the one or more motor mounting means whereby the roller mill provides multiple configurations and multiple connections to allow for multiple variations of volume of product to be milled by various forms of the roller mill.

The roller mill can include two rollers and wherein at least one of the spaced mounting means for mounting the two rollers is adjustably mountable in the second compartment to allow changing to different length rollers.

The roller mill can include two motors mounted substantially parallel but offset to connect to two substantially parallel rollers, such that the spacing of the rollers is less than the spacing of the drive shafts of the motors when standing alongside each other.

The roller mill can have at least one of the motors connected to one of the rollers by a connecting drive shaft with two end universal joints to allow for driving of the at least one roller by the connected motor when the roller and motor drive shaft are not collinear.

It can be seen that the offset nature of the motors and the universal joint connection allows substantial variability of construction over the prior art. In articular the rollers can be sized smaller than the motors in diameter but due to the allowability of change of angle both vertically and horizontally the drive shaft connected by means of the universal joints allow the rollers to be close together. However the same configuration can be used when larger diameter rollers are used as the first roller remains collinear with the first motor drive shaft but he second roller can be offset due to the diameter difference but still be run by the same motor configuration with a different angle provided to the drive shaft from the second motor. The result is not only substantial saving of space but also substantial adaptability of the roller mill to cater for a range of uses.

Also the roller mill can include a drive means with predefinable speed controls such that the roller mill can have predefined speeds for the rollers according to predefined 3 optimal operation in a plurality of modes. Instead of or as well as the roller mill can include a drive means with predefinable speed controls such that the roller mill can have a change of rollers and the drive means has predefined speeds for the original rollers and the changed rollers.

At least one or more of the disadvantages of the prior art are addressed by the present invention, which in one form provides a roller mill for adjusting roller lengths for treatment of grain material, the roller mill including: a housing assembly comprising a floor and ceiling frame structure extending in a longitudinal direction, the floor and ceiling frame structures being interconnected by end wall frame sections; a first partition structure and a second adjustable partition structure fitted to the floor and ceiling frame structure forming a first compartment within the housing assembly, wherein the second partition is adjustable relative to the first partition to controllably alter the size of the first compartment for receiving different lengths of rollers, and wherein the first and second partitions are oppositely disposed and include support surfaces therein for receiving a pair of rollers; a pair of rollers having a substantially cylindrical body and bearing surfaces at each end, wherein the bearing surfaces are rotatably supported by the oppositely disposed support surfaces; and a second compartment within the housing assembly adjacent the first compartment, the second compartment housing at least two drive means interconnected to the rollers for controllably turning the rollers and wherein the at least two drive means are housed in the second compartment in an offset relation.

The present invention allows an operator to adjust the position of the second partition within the first compartment relative to the first partition so as to accommodate a range of different sized rollers at different grain throughput rates.

One advantage of the present roller mill is that a grain producer does not need to progressively buy larger and larger mills processors to cater for increasing grain yields. The present device allows adjustment of one partition member relative to another to accommodate different size rollers. Further the structure of the partitions and the housing assembly allows existing rollers to be easily removed and replaced by a different size of roller. This marks an improvement in cost effectiveness of a 4 milling process since it substantially reduces the need to buy different milling devices for different grain yields.

The first compartment can be altered to accommodate varying lengths of rollers by sliding and locking the second partition structure along a portion of the floor and ceiling frame structure.

The mill roll device of the present invention can be provided to allow speed ratios of one roll with respect to the other in the pair within a range of between about 1:1 to 2:1. The applicant has found that when rotational speed ratios of the pair of rollers is within the above ratio range, the device provides a processed grain which is subject to tearing as opposed to grinding or crushing. This represents a further improvement over prior art roller mills, which can only substantially perform a crushing or grinding physical effect. This effect opens a number of different markets to the grain processing industry.

The support surfaces for supporting the pair of rollers within the first compartment can be slotted openings for slidably receiving the bearing surfaces of each of the pair of rollers. This arrangement allows an operator to easily remove and replace an existing roller within the first compartment. The slotted opening can be centrally located and shaped in an elongate u-configuration. In this way the elongate slot receives the pair of rollers in substantially adjacent arrangement. The roller mill of the present invention can further include a feed delivery device located adjacent the ceiling frame structure to deliver the feed into a gap formed between the pair of rollers. The roller mill can further include a magnet for selectively removing metallic objects prior to feed entering the gap.

It is preferred that each roller be driven independently of the adjacent roller.

It is further preferred that the speed of each roller be independently variable.

In a further preferred embodiment, each roller is driven by an electric motor.

When each roller is driven by an electric motor, it is further preferred that a speed reduction gearbox be interposed between the electric motor and the roller.

In a related aspect of the present invention there is disclosed a process for tearing grain material including: providing a roller mill device having: a housing assembly comprising a floor and ceiling frame structure extending in a longitudinal direction, the floor and ceiling frame structures being interconnected by end wall frame sections; a first partition structure and a second adjustable partition structure fitted to the floor and ceiling frame structure forming a first compartment within the housing I 0 assembly, wherein the second partition is adjustable relative to the first partition to controllably alter the size of the first compartment for receiving different lengths of rollers, and wherein the first and second partitions are oppositely disposed and include support surfaces therein for receiving a pair of rollers; a pair of rollers having a cylindrical body and bearing surfaces at each end, wherein the bearing surfaces are rotatably supported by the oppositely disposed support surfaces and the rollers are oriented in parallel leaving a gap therebetween for receiving grain; a second compartment within the housing assembly adjacent the first compartment, the second compartment housing at least two drive means interconnected to the rollers for controllably turning the rollers and wherein the at least two drive means are housed in the second compartment in an offset relation; and a feed delivery device located adjacent the ceiling frame structure for delivering feed material into the gap between the pair of rollers; including the steps of feeding the grain material into the feed delivery device, and actuating the motors to drive the rollers at a relative speed such that the ratio of rotation of the pair is within the ratio of 1:1 and 2:1, wherein when the grain enters the gap it is subject to a tearing action.

In a further related aspect of the present invention there is disclosed a control system [or processing grain material to achieve a tearing action, the control system including: a housing assembly comprising a floor and ceiling frame structure extending in a longitudinal direction, the floor and ceiling frame structures being interconnected by end wall frame sections; a first partition structure and a second adjustable partition structure fitted to the floor and ceiling frame structure forming a first compartment within the housing assembly, wherein the second partition is adjustable relative to the 6 first partition to controllably alter the size of the first compartment for receiving different lengths of rollers, and wherein the first and second partitions are oppositely disposed and include support surfaces therein for receiving a pair of rollers; a pair of rollers having a substantially cylindrical body and bearing surfaces at each end, S wherein the bearing surfaces are rotatably supported by the oppositely disposed support surfaces and the rollers are oriented in parallel leaving a gap therebetween for receiving grain; a second compartment within the housing assembly adjacent the first compartment, the second compartment housing at least two drive means interconnected to the rollers for controllably turning the rollers and wherein the at I i least two drive means are housed in the second compartment in an offset relation; and wherein the motors are geared to control the rate of rotation of the rollers such that the rollers rotate relative to each other in a rotational speed ratio ranging between about 1:1 to 2:1 and wherein within this ratio grain introduced into the gap between the pair of rollers is subject to tearing action.

It is further preferred that the speed of at least one of the motors driving adjacent rollers be electronically controlled.

Brief Description of the Views of the Drawings: In order that the invention may be more readily understood, preferred embodiments of it will now be described with reference to the drawings wherein: Figure 1 is a side perspective view of a roller mill according to one embodiment of the present invention; Figure 2 is an enlarged partial side perspective view of one compartment of the roller mill device shown in figure 1 without the rollers; Figure 3 is a detailed schematic overhead view of a roller mill in accordance with the embodiment of the invention of Figure 1; Figure 4 is a detailed schematic side view of a roller mill in accordance with the embodiment of the invention of Figure 1; and Figure 5 is a detailed schematic end view of a roller mill in accordance with the embodiment of the invention of Figure 1.

Description of An Embodiment of the Invention with reference to the accompanying drawings Referring to figure 1 there is shown an improved roller mill 1 according to one embodiment of the present invention. The roller mill 1 includes a modular elongated rectilinear skeletal framework housing 2 wherein the housing has open sides to allow ready connection to modular input and output feeders. In particular as shown in Figure 4 a modular input feeder 35 can simly be attached to the framework housing 2.

The roller mill 1 further includes two motors 31, 32 on mounting means 25 in the framework housing 2, and spaced mounting means 9, 15 attached to the elongated rectilinear skeletal framework housing 2 and extending across the housing to form an adjacent second compartment for receiving and mounting two rollers 12, 18 in substantially parallel configuration and connected to and driven by the motors mounted.

The roller mill includes a framework housing structure 2 having an elongate floor frame section 3 and an oppositely disposed ceiling frame section 4 interconnected by wall frame sections 5 and 6. The housing structure 2 is divided into at least two compartments 7 and 8. The roller mill can include two rollers and wherein at least one of the spaced mounting means for mounting the two rollers is adjustably mountable in the second compartment to allow changing to different length rollers.

Compartment 7 is separated from compartment 8 by means of a fixed partition member 9. Partition member 9, which is best shown in figure 2, includes a centrally located elongated u-shaped slot 10, which receives a bearing element 11 of a roller 12 in sliding arrangement. Partition member 9 is bolted to the floor and ceiling frame by means of a bracket 13 and bolts 14. The partition member 9 includes cut-out sections at each corner shaped to be received and fitted to the floor and ceiling frame sections.

The compartment 7 further includes an adjustable partition member 15, shown spaced from and oppositely disposed to partition member 9. Partition member 15 includes a centrally located elongate u-shaped slot 16, which receives a bearing element 17 of roller 12 in sliding arrangement. Compartment 7 houses a pair of rollers 12 and 18, which are axially aligned and in an operational condition rotate in opposite directions.

As shown in figures] and 2, partition member 15 and partition member 9 are spaced to provide a compartment for accommodating a pair of steel rollers 12 and 18. The rollers are located to provide a gap therebetween for receiving grain matter. Each roller 12 and 18 has a cylindrical body having cylindrical bearings 17 at their ends.

The cylindrical bearings allow each roller to be slidably received within oppositely disposed slots in partition members 9 and 15. The roller bodies are located between the opposite slots to rotate freely in a contra-rotating manner. The roller bearings allow lateral sliding movement within the slot for positioning each roller and to allow substantially free rotation on the bearing surface within the slot about a rotational axis central of the roller body. The roller body can have a surface, which includes grooves or other profiles to aid drawing of grain material into a gap.

Partition member 15 is able to be adjusted along the length of the floor and ceiling frame sections to accommodate roller lengths ranging between about 400mm to about 1000mm. In figure 1, partition member 15 is mounted to the ceiling and floor frame section at a distance from wall frame end 6 to accommodate a relatively large pair of contra-rotating rollers. Figure 1 also shows alternative positions 19 and 20 on the housing where partition member 15 may be relocated to accommodate progressively smaller length rollers. This aspect of the present invention allows a grain producer to start with a small pair of rollers and substitute progressively larger rolls without needing to buy a whole new milling device.

The roller mill 1 further includes a feed delivery device such as a hopper 35 located adjacent the ceiling frame section with an exit opening located adjacent the gap between the pair of rollers. The hopper includes a slide member 29, which operates to open and close the exit opening. The roller mill further includes a magnet or magnetic field generating device (not shown) to remove extraneous metallic particles from the grain prior to exiting the hopper.

The roller mill can include two motors mounted substantially parallel but offset to connect to two substantially parallel rollers, such that the spacing of the rollers is less than the spacing of the drive shafts of the motors when standing alongside each other.

9 The roller mill can have at least one of the motors connected to one of the rollers by a connecting drive shaft with two end universal joints to allow for driving of the at least one roller by the connected motor when the roller and motor drive shaft are not collinear.

In figure 1, compartment 8 houses a first motor 31 powering roller 12 and a second motor 32 in an offset relation powering roller 18. Motor 31 is interconnected to roller 12 by means of a universal joint 23 and 24. The compartment 8 includes a base support structure 25 extending across the floor frame section 3 to provide a seat for motor 31 within the housing 2. Further spaced supports 26 and 27, provide a base for seating motor 32 within the housing. The roller 12 is powered by an electronically controlled variable speed electric motor 31 through a fixed-ratio reduction gearbox and a coupling. The roller 18 is powered by an electronically controlled variable speed electric motor 32 through a fixed-ratio reduction gearbox and a coupling.

Referring to Figures 3, 4 and 5 it can be seen that the offset nature of the motors 31, 32 and the universal joint connection 23, 24 allows substantial variability of construction over the prior art. In particular the rollers 12, 18 can be sized smaller than the motors 31, 32 in diameter but due to the allowability of change of angle both vertically and horizontally (see particularly Figure 4) the drive shaft connected by means of the universal joints 23, 24 allow the rollers 12, 18 to be close together.

H-owever the same configuration can be used when larger diameter rollers are used as the first roller remains collinear with the first motor drive shaft but he second roller can be offset due to the diameter difference but still be run by the same motor configuration with a different angle provided to the drive shaft from the second motor.

The result is not only substantial saving of space but also substantial adaptability of the roller mill to cater for a range of uses.

Also the roller mill can include a drive means with predefinable speed controls such that the roller mill can have predefined speeds for the rollers according to predefined optimal operation in a plurality of modes. Instead of or as well as the roller mill can include a drive means with predefinable speed controls such that the roller mill can have a change of rollers and the drive means has predefined speeds for the original rollers and the changed rollers.

According to this embodiment of the invention, the electric motors 21 and 22 operate to control the rotational speed of rollers 12 and 18 such that the ratio of the speed of rotation varies from 1:1 to 2:1. In this range of speed ratios, the applicant has found that grain passing into a gap between an adjacent pair of rollers is subject to tearing as opposed to grinding or crushing. This represents an improvement over existing roller minills.

Preferred speeds for new rolls are in the range of 500 rpm to 600 rpm. As the rolls wear, the electric motors 4 and 8 are controlled to run at different speeds. It is preferred that the speed of each variable speed roll be adjustable over a range of plus and minus 100 rpm.

In an operating condition, harvested grain is conveyed to the hopper (not shown).

Once the hopper device is loaded a control slide is actuated to allow egress of grain from the hopper directed to a gap formed between a pair of steel rollers. The roller mill device subsequently provides control of dual motors interconnected to one of each pair of rollers to subject the grain to contra-rotating rollers rotating at a relative speed within the ratio of between 1:1 and 2:1. The roller mill device in accordance with the present invention provides a housing having adjacent compartments for separately housing the pair of steel rollers and the independent driving means. The compartment housing the pair of rollers is adjustable so that rollers of different length can be inserted to cater for varying grain quantities.

It is preferred that each roll have a diameter in the range 250mm to 450mm.

Claims (22)

1. A roller mill having a modular elongated rectilinear skeletal framework housing wherein the housing has open sides to allow ready connection to modular input and output feeders and further including one or more motor mounting means for receiving and mounting one or more motors in a first compartment; and spaced mounting means attached to the elongated rectilinear skeletal framework housing and extending across the housing to form an adjacent second compartment for receiving and mounting one or more rollers in substantially parallel configuration and able to be connected to and driven by one or more motors mounted on the one or more motor mounting means whereby the roller mill provides multiple configurations and multiple connections to allow for multiple variations of volume of product to be milled by various forms of the roller mill.

2. A roller mill according to claim 1 including two rollers and wherein at least one of the spaced mounting means for mounting the two rollers is adjustably mountable in the second compartment to allow changing to different length rollers.

3. A roller mill according to claim 1 or 2 including two motors mounted substantially parallel but offset to connect to two substantially parallel rollers, such that the spacing of the rollers is less than the spacing of the drive shafts of the motors when standing alongside each other.

4. A roller mill according to claim 3 wherein at least one of the motors is connected to one of the rollers by a connecting drive shaft with two end universal joints to allow for driving of the at least one roller by the connected motor when the roller and motor drive shaft are not collinear.

5. A roller mill according to any one of the preceding claims including a drive means with predefinable speed controls such that the roller mill can have predefined speeds for the rollers according to predefined optimal operation in a plurality of modes.

6. A roller mill according to any one of the preceding claims including a drive Smeans with predefinable speed controls such that the roller mill can have a change of rollers and the drive means has predefined speeds for the original 0 5 rollers and the changed rollers.

7. A roller mill for adjusting roller lengths and treatment of material, the roller Smill including: a. a housing assembly comprising a floor and ceiling frame structure extending in a longitudinal direction, the floor and ceiling frame structures being interconnected by end wall frame sections; b. a first partition structure and a second adjustable partition structure fitted to the floor and ceiling frame structure forming a first compartment within the housing assembly, wherein the second partition is adjustable relative to the first partition to controllably alter the size of the first compartment for receiving different lengths of rollers, and wherein the first and second partitions are oppositely disposed and include support surfaces therein for receiving a pair of rollers; c. a pair of rollers having a substantially cylindrical body and bearing surfaces at each end, wherein the bearing surfaces are rotatably supported by the oppositely disposed support surfaces; and d. a second compartment within the housing assembly adjacent the first compartment, e. at least two drive means in the second compartment housing interconnected to the rollers for controllably turning the rollers and with the at least two drive means being housed in the second compartment in an offset relation.

8. A roller mill according to claim 7 including two motors mounted substantially parallel but offset to connect to two substantially parallel rollers, such that the spacing of the rollers is less than the spacing of the drive shafts of the motors when standing alongside each other.

9. A roller mill according to claim 7 or 8 wherein at least one of the motors is (,i N connected to one of the rollers by a connecting drive shaft with two end universal joints to allow for driving of the at least one roller by the connected motor when the roller and motor drive shaft are not collinear. tt 10. A roller mill according to claim 7, 8 or 9 wherein the present invention allows t an operator to adjust the position of the second partition within the first compartment relative to the first partition to accommodate a range of sets of 10 different sized rollers to provide different material throughput rates. ('i

11. A roller mill according to any one of the preceding claims wherein the roller mill is for milling grain and the changeability of a plurality of a) different length rollers; b) different orientation of rollers to motors; c) different diameter rollers; and d) different predefined speed control of the rollers; provides a multitude of configurations whereby the grain processor does not need to progressively buy larger and larger mills to cater for processing varying grain yields.

12. A roller mill according to claim 10 wherein adjustment of one partition member relative to another allows accommodation of different size rollers with the structure of the partitions including U shaped openings allows for easy replacement and the housing assembly allowing existing rollers to be easily removed and replaced by a different size of roller.

13. A roller mill according to any one of claims 7 to 10 wherein the first compartment can be altered to accommodate varying lengths of rollers by sliding and locking the second partition structure along a portion of the floor and ceiling frame structure.

14. A roller mill according to any one of claims 7 to 10 for processing grain according to claim 9 wherein the motor provides speed ratios of one roll with respect to the other in the pair within a range of between about 1:1 to 2:1. A roller mill according to any one of claims 7 to 10 wherein the support N surfaces for supporting the pair of rollers within the first compartment can be slotted openings for slidably receiving the bearing surfaces of each of the pair 0 5 of rollers whereby this arrangement allows an operator to easily remove and replace an existing roller within the first compartment. t 16. A roller mill according to any one of claims 7 to 10 wherein the slotted opening can be centrally located and shaped in an elongate U-configuration. ('i In this way the elongate slot receives the pair of rollers in substantially adjacent arrangement. (-i

17. A roller mill according to any one of claims 7 to 10 wherein the roller mill of the present invention can further include a feed delivery device located adjacent the ceiling frame structure to deliver the feed into a gap formed between the pair of rollers.

18. A roller mill according to any one of claims 7 to 10 wherein the roller mill can further include a magnet for selectively removing metallic objects prior to feed entering the gap.

19. A roller mill according to any one of claims 7 to 10 wherein each roller be driven independently of the adjacent roller.

20. A roller mill according to any one of claims 7 to 10 wherein the speed of each roller be independently variable.

21. A roller mill according to any one of claims 7 to 10 wherein each roller is driven by an electric motor.

22. A roller mill according to any one of claims 7 to 10 wherein each roller is driven by an electric motor with a speed reduction gearbox interposed between the electric motor and the roller. IN lr- 10

23. A process for tearing grain material including: a. providing a roller mill device having: b. a housing assembly comprising a floor and ceiling frame structure extending in a longitudinal direction, the floor and ceiling frame structures being interconnected by end wall frame sections; c. a first partition structure and a second adjustable partition structure fitted to the floor and ceiling frame structure forming a first compartment within the housing assembly, wherein the second partition is adjustable relative to the first partition to controllably alter the size of the first compartment for receiving different lengths of rollers, and wherein the first and second partitions are oppositely disposed and include support surfaces therein for receiving a pair of rollers; d. a pair of rollers having a cylindrical body and bearing surfaces at each end, wherein the bearing surfaces are rotatably supported by the oppositely disposed support surfaces and the rollers are oriented in parallel leaving a gap therebetween for receiving grain; e. a second compartment within the housing assembly adjacent the first compartment, the second compartment housing at least two drive means interconnected to the rollers for controllably turning the rollers and wherein the at least two drive means are housed in the second compartment in an offset relation; and f. a feed delivery device located adjacent the ceiling frame structure for delivering feed material into the gap between the pair of rollers; g. including the steps of h. feeding the grain material into the feed delivery device, and i. actuating the motors to drive the rollers at a relative speed such that the ratio of rotation of the pair is within the ratio of 1:1 and 2:1, wherein when the grain enters the gap it is subject to a tearing action.

24. A control system for processing grain material to achieve a tearing action, the control system including: a. a housing assembly comprising a floor and ceiling frame structure extending in a longitudinal direction, the floor and ceiling frame structures being interconnected by end wall frame sections; b. a first partition structure and a second adjustable partition structure 0 5 fitted to the floor and ceiling frame structure forming a first compartment within the housing assembly, wherein the second t partition is adjustable relative to the first partition to controllably alter Sthe size of the first compartment for receiving different lengths of rollers, and wherein the first and second partitions are oppositely disposed and include support surfaces therein for receiving a pair of rollers; c. a pair of rollers having a substantially cylindrical body and bearing surfaces at each end, wherein the bearing surfaces are rotatably supported by the oppositely disposed support surfaces and the rollers are oriented in parallel leaving a gap therebetween for receiving grain; d. a second compartment within the housing assembly adjacent the first compartment, the second compartment housing at least two drive means interconnected to the rollers for controllably turning the rollers and wherein the at least two drive means are housed in the second compartment in an offset relation; and e. wherein the motors are geared to control the rate of rotation of the rollers such that the rollers rotate relative to each other in a rotational speed ratio ranging between about 1:1 to 2:1 and wherein within this ratio grain introduced into the gap between the pair of rollers is subject to tearing action. A control system according to claim 24 for processing grain material to achieve a tearing action wherein the speed of at least one of the motors driving adjacent rollers be electronically controlled.

26. A roller mill substantially as hereinbefore described with reference to the drawings.