GB2385296A

GB2385296A - Apparatus and method for the production of shavings

Info

Publication number: GB2385296A
Application number: GB0203717A
Authority: GB
Inventors: Len Dawkins
Original assignee: Individual
Current assignee: Individual
Priority date: 2002-02-16
Filing date: 2002-02-16
Publication date: 2003-08-20
Also published as: GB0203717D0

Abstract

Apparatus for making shavings (e.g. wood shavings for animal bedding or paper pulp) comprises a guide track 101 on which are mounted a plurality of feedstock gripping means 103. Movement of these gripping means 103 past a plurality of cutters 110 and 113-115 arranged above the track 101 shaves material from the feedstock. The cutters 110 and 113-115 are mounted progressively closer to the track 101 whereby several layers of shavings can be cut during a single passage of the gripping means 103 past the cutters 110 and 113-115. After each passage, the position of the cutters 110 and 113-115 relative to the track 101 is adjusted to enable further shavings to be cut. The apparatus comprises means to both individually and collectively adjust the position of the cutters 110 and 113-115 relative to the track 101.

Description

APPARATUS AND METHOD FOR THE PRODUCTION OF WOOD SHAVINGS Field of the Invention The present invention relates to apparatus and methods for the reduction in size of a quantity of material by the production of material shavings and particularly, although not exclusively, to apparatus and methods for the production of wood shavings.

Background to the Invention Wood shavings are known to be used as animal bedding, being particularly suitable as a bedding material for horses as well as other farm and domestic animals.

Traditionally, wood shavings for use in animal bedding have been obtained by one of two routes. A first route is labour intensive, requiring the collection of waste wood shavings from timber merchants, joiners and other general woodworking and shaping industries. Joinery machines, for example, are known for the manipulation of wood, in particular the shaving, molding and planing of wood to produce particular wood shapes and configurations. As a waste material these machines generally produce wood shavings of various shapes and sizes.

Traditional wood shaving contractors have collected this waste material, removed the associated dust and particulates, baled the resulting wood shavings and sold the material as animal bedding.

A second route to the production of wood shavings comprises the use of purpose built machines designed to produce wood shavings from lengths of timber. Machines are known in the prior art for producing wood shavings for use in animal bedding. Examples include US 3,286, 745 and US 2,442, 492. These machines generally comprise a hopper into which long lengths of timber mainly produced by the forestry industry are placed. Typically, it is a requirement that P0800. spec

timber for these types of prior art machinery are of a length greater than 300 mm up to a length in the region of 6000 mm. A hopper loaded with timber can be moved across one or more cutting elements to remove shavings from the timber upon each movement across the cutting element. As each shaving is removed, gravity acts to force the remaining timber down onto the cutting element.

Wood granulators are also known in the prior art, for example granulators manufactured by Weima Maschinenbau GmbH. These machines generally provide a means to reduce wood into granules or chippings having sharp edges, being potentially injurious edges increasing the risk of obtaining splinters and consequently of no commercial value for use as animal bedding. Further, chippings and granules thus formed are particularly disadvantageous due to their lack of absorbency if used as animal bedding.

Wood grinders are also known in the prior art to recycle wood waste, being of similar construction to wood granulators. Grinders generally reduce wood waste to a particle size suitable for the chipboard industry, being too large for use as animal bedding.

Timber merchants, joiners, carpenters and other wood working practitioners generally produce wood off cuts, being short lengths of wood having no general purpose to the wood working practitioner and generally being the result of trimming a length of timber to a required size. Typically, wood off cuts are in the range of up to 600 mm in length. However, wood off cuts can be of various shapes, sizes and dimensions depending upon the particular practitioner utilising the wood and length of wood which is being worked. Such off cuts form waste materials which are typically disposed of in land-fill sites or through incineration. Neither of these disposal methods is environmentally friendly. One option for further utilizing such wood off cuts is to produce wood shavings for use in either animal bedding or as the principle constituents in the formation of paper pulp.

Prior art machinery does not lend itself to the production of wood shavings from such wood off cuts due to a general inability of such machines to multi-feed short lengths of stock with various thicknesses without having to make considerable adjustments to the machinery operation, tooling and setup. Many wood working machines require through feeding of the timber along a linear feed table. Short lengths of timber make this operation difficult and dangerous due to the need to pass the short length of timber past the cutting or shaping element. Typically, working of such short lengths of wood would require use of a further work piece to drive the wood off cut through the machinery.

Machines for production of wood shavings, such as those described in US 3,286, 745 and US 2,442, 492 are not suitable for production of wood shavings from a wide variety of wood lengths, shapes and sizes such as those found in general wood off cuts. These prior art machines are configured to produce wood shavings from large, uniform wood lengths mainly produced in the forestry industry wherein an approximately uniform surface can be consistently presented to the cutting element and an even weight distribution of the wood is presented to the cutting element.

The inventor has therefore identified a technical problem presented by the prior art in that the prior art does not provide for apparatus for the production of wood shavings from varying shapes and sizes of off cut waste wood lengths which avoids the problem of feeding small lengths of stock through existing woodworking machinery.

Summary of the Invention It is an object of the present invention to provide apparatus for the production of wood shavings from off cut lengths of waste wood.

It is a further object of the present invention to recycle off cut lengths of waste wood by producing wood shavings for further commercial use.

The inventor has realised that the large amount of waste wood produced by wood working agents, which is normally disposed of by incineration or at landfill, can provide a cheap, and in many cases free, source of material for the production of wood shavings. The recycling of this waste material has significant environmental benefits.

The inventor has therefore provided an apparatus for mounting at least one waste off cut item of wood securely at a securing means which can be moved relative to at least one cutting element. By movably mounting a plurality of securing means, arranged adjacently on a track, each securing means configured to house an item of off cut waste wood, a plurality of waste wood items can effectively form a single length of timber for presentation to at least one cutting element for the production of shavings from each item of wood.

The inventor has further realised that by providing a plurality of cutting elements, each element displaced vertically from the track upon which each securing means is mounted by a varying amount decreasing between each cutting element in the order in which each securing means passes each cutting element during movement, that several layers of wood shavings can be removed from a single wood item during one passage of a securing means and wood item past the set of cutting elements.

The inventor has further realised that by adjusting the height of each cutting element between passages of movement of the securing means past each cutting element that a further set of shavings can be removed by each cutting element during a single sweep of a securing means past the cutting element set.

By providing a securing means adjustable to securely receive and mount wood items of varying size and shape it is possible to process short lengths of waste wood to form wood shavings without risk of injury to the user due to the fact that there is no need for the user to manually guide the wood item past the cutting elements. Hydraulic, pneumatic and vacuum powered securing means

provide effective and efficient means of securely mounting a wood item for presentation to a cutting element for formation of wood shavings.

The inventor has provided a means to produce calibrated wood shavings of uniform size from waste wood off cuts. The apparatus of the present invention enables the production of wood shavings from wood off cuts of various widths and sizes avoiding the associated problems of feeding small lengths of stock through conventional wood planers/molders.

The inventor has provided an apparatus and method for converting wood waste to wood shavings. Horizontally orientated cutter blocks are positioned in a circular line to reduce a stock of wood gripped by one of a plurality of securing means, each securing means linked together and mounted such as to move beneath and within the same circular line in which the cutter blocks are mounted.

Each securing means is mounted on a circular guide track to guide movement beneath each cutter block. Each securing means is further attached to a radial arm positively fixed to a rotary table positioned at the centre point of the circular guide track. Optionally, each radial arm is further positioned by the use of circular linear guides and mounting blocks mounted at an intermediate guide track positioned between the rotary table and the circular guide track mounting the securing means. Use of cyclo-geared servo or stepper motors enables variable speed motion control of the rotary table and connected radial arms. A control means in the form of a processor, e. g. the 6K multi-axis motion controller made

TM by Parker Automation, controls the servo or stepper motors monitoring the position of the motors to accurately monitor completion of a sweep of the securing means past the cutter block. Alternatively, a sensing means in the form of a proximity switch is provided to detect the completion of such a sweep. This information is processed by the control means so as to briefly stop movement of the securing means after each revolution. By utilizing information relating to speed of rotation, the processor is configured to monitor the exact position of the servo or stepper motor and thereby the position of each securing means. Upon detecting completion of a sweep of the securing means past the set of cutter

blocks each cutter block is realigned by a self adjustment mechanism to lower the position of each cutter block with respect to the height of the circular guide track such as to engage the wood stock gripped in each securing means to produce wood shavings from the stock during a subsequent sweep.

Whilst the inventor has considered use of the apparatus of the present invention for the production of wood shavings the apparatus is suitable to produce shavings from any material which can be gripped in a securing means, and presented to a cutting edge such as to produce shavings of the material.

Other materials which could be reduced in size by the production of shavings in accordance with the present invention comprising, for example, plastics materials.

According to a first aspect of the present invention there is provided apparatus for the reduction in size of a quantity of material by the production of shavings of said material, said apparatus comprising: at least one securing means configured to grip a quantity of material for presentation of said material to said at least one cutting element, wherein said securing means or said cutting element are moveable relative to the other to pass said quantity of material past said at least one cutting element, thereby presenting said material to said cutting element in order to produce at least one material shaving, wherein said apparatus is configured for adjustment of the spatial relationship between said cutting element and said securing means so as to permit production of material shavings from said quantity of material during a subsequent presentation of said quantity of material to said cutting element.

Preferably, each said securing means is mounted on a guide, said securing means moveable past said cutting elements.

Preferably, said cutting elements are mounted above a section of said guide.

Preferably, said apparatus comprises a plurality of cutting elements arranged consecutively along a section of said guide.

Preferably, each said cutting element comprises a substantially cylindrical body having at least one cutting edge extending from said body, said cutting element rotatable about a main longitudinal axis to present said cutting edge to a quantity of said material in order to engage said material and produce a shaving of said material.

Preferably, adjacent said cutting elements are arranged such that the vertical displacement between said cutting element and said guide varies between adjacent cutting elements.

Preferably, adjacent cutting elements are arranged in order of decreasing size of said displacement.

Preferably, said apparatus further comprises sensing means to detect passage of said securing means past said cutting elements.

Preferably, said apparatus further comprises means to adjust the displacement of said cutting elements from said guide.

Preferably, said means to adjust comprises means to adjust the displacement of all of the cutting elements simultaneously and separate means to individually adjust the displacement of individual cutting elements.

Preferably, upon detection of passage of a said securing means past said cutting elements, the displacement of each of said cutting elements from said guide is automatically adjusted.

Preferably, adjustment of said displacement comprises lowering of said cutting elements towards said guide.

Preferably, adjustment of said displacement comprises raising said guide towards said cutting elements.

Preferably, said apparatus further comprises a control means, said control means receiving information from said sensing means and operating to automatically adjust said displacement upon detection of passage of a said securing means past said cutting elements.

Preferably, said securing means comprises a plate member configured for location of a said quantity of material and a gripping means to grip said quantity of material.

Preferably, said plate member comprises at one end a first wall portion, said gripping means comprising a second wall portion urged resiliently towards said first wall portion and configured to trap a quantity of said material there between.

Preferably, said securing means comprises a pneumatically or hydraulically powered ram causing said second wall portion to be urged towards said first wall portion.

Preferably, said plate member further comprises a sealing member formed on said plate member and defining a polygon or ring, a plurality of apertures formed in said plate member within the area defined by said polygon or ring.

Preferably, said securing means is connected to a vacuum pump configured to draw air through said apertures, a said quantity of material placed over said sealing member thereby retained in position by said vacuum.

Preferably, said guide comprises a first circular track, a plurality of said securing means mounted upon said track, each said securing means connected to a rotary member positioned at the centre of said track by a radial arm extending from said rotary member to a respective said securing means.

Preferably, said rotary member is operable via a control means and drive means for controlled rotation of said rotary member, radial arms and securing means.

Preferably, said apparatus further comprises a second circular guide located between said rotary member and said first circular track, adjacent said radial arms connected by spacer elements, wherein at least one said radial arm is mounted upon said second circular guide.

Preferably, said guide comprises a radial arm connected to a rotary member and said securing means and extending there between, rotation of said rotary member causing movement of said securing means.

Suitably, said guide comprises a track comprising a slotted portion, said securing means further comprising a projecting portion configured to extend through said slotted portion, said projecting portion further configured to prevent substantial lifting of said securing means from said track.

Preferably, said securing means further comprises at least one movement member engageable at a portion of the underside of said track to further define movement of said securing means.

Preferably, said material is wood.

Preferably, said apparatus is configured for the production of wood shavings for use in animal bedding.

Suitably said apparatus may be configured for the production of wood shavings for use in the production of paper or cardboard or any product that has wood shavings as all or part of its makeup.

According to a further aspect of the present invention there is provided apparatus for the production of wood shavings from at least one quantity of wood, said apparatus comprising: a guide track; and at least one securing means moveably mounted upon said guide track, each said securing means configured to securely position a quantity of wood; and at least one cutting element mounted above a section of said guide track and arranged to contact said quantity of wood upon a first movement of said securing means along said guide track past said cutting element so as to produce at least one wood shaving therefrom, wherein, said cutting element position is adjustable to vary the displacement of said cutting element from said guide track so as to arrange a said cutting element to contact said quantity of wood upon a second said movement of said securing means.

Preferably, said guide track is circular, each said securing means further comprising a radial arm extending from said securing means towards a rotary member located at a central position within said guide track, said radial arm fixedly attached to said rotary member, wherein rotation of said rotary member effects movement of said securing means about said track.

Preferably, said apparatus comprises a plurality of said cutting elements arranged above a portion of said track, each said cutting element vertically offset from an adjacent cutting element such that a first said cutting element encountered during rotation of said securing means comprises a cutting edge contacting said quantity of wood at a position of greater vertical displacement to said guide track than the next adjacent cutting element arranged in the direction of rotation of said securing means.

According to a first specific method of the present invention there is provided a method for the reduction in size of a quantity of material by the production of shavings of said material comprising the steps of: loading a quantity of said material at a securing means said securing means gripping said quantity of material ; and moving said securing means and material past at least one cutting element to produce a material shaving; and adjusting the spatial relationship between said cutting element and said securing means; and moving said securing means and quantity of material past said cutting element so as to produce a second material shaving.

Preferably, said method further comprises the steps of: sensing movement of said securing means past a said cutting element ; and automatically adjusting said spatial relationship.

Preferably, said method further comprises the steps of:

collecting material shavings and forming said collected shavings into a bale.

Preferably, said step of adjustment of said spatial relationship comprises lowering a said cutting element.

Preferably, said step of adjustment of said spatial relationship comprises raising said securing means.

Preferably, said material comprises wood.

Brief Description of the Drawings For a better understanding of the invention and to show how the same may be carried into effect, there will now be described by way of example only, specific embodiments, methods and processes according to the present invention with reference to the accompanying drawings in which: Fig. 1 illustrates a perspective view of the woodshaving apparatus in accordance with the first embodiment of the present invention; Fig. 2 illustrates an enlarged view of the wood shaving apparatus of fig. 1 illustrating a part of the adjustment means for adjusting the height of each cutting element; Fig. 3 illustrates diagrammatically a perspective view of one type of cutting element ; Fig. 4 illustrates diagrammatically an end view of one type of cutting element; Fig. 5 illustrates a perspective view of a securing means and hydraulic/pneumatic ram for securing an item of wood according to the first embodiment of the present invention;

Fig. 6A illustrates a side view of two wood items fastened together with adhesive and mounted on a mounting block, the combination of mounting block and wood items held at a securing means by a vacuum in accordance with the second embodiment of the present invention; Fig. 6B illustrates a plan view of the securing means and base plate of the securing means of fig. 6A illustrating a sealing member and apertures for formation of a vacuum; Fig. 7 illustrates schematically a flow diagram illustrating the steps involved in implementing the method of the present invention; Fig. 8 illustrates a schematic diagram of the layout of the control means, stepper or servo motor drive controllers and associated motors; Fig. 9 illustrates a further securing means embodiment.

Detailed Description of the Best Mode for Carrying Out the Invention There will now be described by way of example the best mode contemplated by the inventors for carrying out the invention. In the following description numerous specific details are set forth in order to provide a thorough understanding of the present invention. It will be apparent however, to one skilled in the art, that the present invention may be practiced without limitation to these specific details. In other instances, well known methods and structures have not been described in detail so as not to unnecessarily obscure the present invention.

In this specification the term shaving relates to a thin portion of material removable from a main quantity of material by cutting said material with a sharp edge. A shaving generally comprising a layer of the material.

Referring to figure 1 herein there is illustrated in diagrammatic form a perspective view of the apparatus according to a first embodiment of the present invention. A circular guide track 101 forming a material strip extending to form a loop provides a base layer to guide movement of items of wood stock in order to present the wood stock to at least one cutting element in order to produce wood shavings. Guide track 101 comprises a groove or rail 102 for location of each securing means and to define a path for movement of the securing means 103 around the guide track 101 A plurality of securing means 103 are provided, each securing means providing a means to securely grip a quantity of wood such that the gripped wood moves with the securing means 103 around the guide track 101 so as to be presented to cutting elements 110 in order to produce wood shavings. Located at a central region within the external guide track 101 is a rotary table 107.

Rotary tables 107 are known in the prior art, for example the 200 RT series manufactured by Parker Automation TM. The rotary table 107 provides a high precision means of driving securing means 103 movement. One suitable rotary table comprises a main support bearing, comprised of two reloaded angular contact bearing races. Rotational movement is driven by a precision worm gear assembly, reloaded so as to remove backlash. Rotary table 107 is further connected to a movement means, typically a servo or stepper motor. Optionally an intermediate gear box may be provided to provide further variable speed control. One example of a suitable gear box is the fine cyclo-series manufactured by Sumitomo providing minimal backlash, low vibration, hightorque to weight ratios and being suitable for applications where frequent starting and stopping of rotary motion is required.

Fastened to a flange formed at rotary table 107, there are provided a plurality of radial arms 104 comprising material strips, typically made of metal or rigid plastics of uniform cross section. A single arm 104 is provided for each securing means 103. Each radial arm extending from a position at rotary table 107 in a radial direction towards guide track 101 where radial arm 104 is fastened

at a second end to securing means 103. Each radial arm 104 is fastened at a first end to rotary table 107 by means of conventional fastening means e. g. rivets or locking bolts.

The radial arms 104 are attached to the flange formed at the rotary table 107 so that the first and last radial arm is clear of the cutter block configuration when the rotary table 107 is stationary. This occurring between sweeps of the securing means 103 whilst cutter block height adjustment is occurring and during loading and unloading of the securing means 103.

Positioned between central rotary table 107 and external circular guide track 101 there is further provided an intermediate circular guide track 106.

Intermediate guide track 106 comprises a circular strip of sheet material provided with a raised guide surface 105. Guide surface 105 provides a rail for the mounting of at least one linear motion guide block 111. Suitable linear motion guide blocks include linear motion guides comprising caged ballTM technology manufactured by THK UKTM. Each linear guide comprising a set of ball bearing races enabling movement of the guide block 111 around the guide rail 105. At least one guide block 111 is provided which is fastened to a radial arm 104 at a position between the first and second ends of radial arm 104. Figure 1 illustrates seven linear guide blocks 111 connected to alternatively spaced radial arms 104.

Further provided between each radial arm 104 is a spacing element 112 comprising a rigid bar forming a linear spacer or strut connected to adjacent radial arms to maintain a uniform spacing of said radial arms and providing rigidity to each radial arm and the overall structure. Movement of rotary table 107 in a rotational direction drives movement of the securing means 103 on the guide track 101, this movement being maintained in uniform and smooth fashion by means of the intermediate guide track 106 and the linear mounting blocks 111 and spacers 112. Guide blocks 111 and spacing elements 112 increase the rigidity of the securing means and associated moveable apparatus. This acts to increase the level of precision of movement control enabling rapid start-up and stopping of securing means movement with minimal backlash. By strengthening

each radial arm by provision of the intermediate circular guide track 106, struts 112 formed between each radial arm, and the linear guide blocks 111, a uniformity of rotational movement of the set of securing means is provided.

Each of the guide tracks 101,106 is firmly fastened at a flat surface forming a main structural frame of the apparatus. By providing a plurality of linear guide blocks, either positioned at alternate radial arms or at each radial arm, and mounting these guide blocks at a guide rail 105, motion created by rotation of the rotary table acts to rotate the securing means whilst the guide blocks 111 provide precision arc motion eliminating looseness and vibration of the radial arms.

Further referring to figure 1 herein there are illustrated a plurality of cutting elements 110 arranged around a portion of exterior guide track 101 and positioned above the horizontal level of the track 101 in the same approximate arc configuration as the securing means 103. Each cutting element comprises a substantially cylindrical cutter block of a type as illustrated in figures 2 and 3 herein and described further below. The size and shape of each cutter block is not a limiting aspect of the invention, any suitable cutting edge which can be presented to the material housed in the securing means and from which shavings can then be produced may be used.

Each cutter block 110 is mounted at a housing 108,109 such as to mount cutter blocks 110 to extend in a direction transverse to the direction of movement of securing means 103 past the relevant cutter on the guide track 101 whilst being located above guide track 101, each cutter block 110 located at a predetermined height or displacement from the main guide track surface 101.

Each cutter block 110 has a main longitudinal axis maintained in substantially parallel relationship to the main upper surface of guide track 101. Rotation of cutter block 110 is driven by associated motors (e. g. motor 206 illustrated in fig.

2) and geared drives. In one arrangement a flat belt drive system operates between the shaft of the motor and the cutter block shaft. The flat belt drive system being housed in the cutter block housing 108,109. This drive system

ensures a vibration free operation. The driving motor is normally mounted on the cutter block housing 108,109.

Further referring to figure 1 herein there are specifically illustrated eight cutter blocks arranged around a portion of one hemisphere of the guide track 101. Rotary table 107 is operated to drive movement of the securing means in a mode of rotation such as to present a quantity of wood held in each securing means first to cutter block 113 and lastly to cutter block 114 during a single sweep. Having loaded each securing means with a quantity of wood which is to be reduced by the removal of wood shavings, the cutter blocks are located in an initial state. The initial state comprises location of first cutter block 113 at a predetermined initial position. Immediately adjacent cutter blocks are automatically leveled at corresponding predetermined initial positions wherein each adjacent cutter block is located at a position further towards exterior guide track 101 main surface such that the gap formed between the main longitudinal axis of each cutter block and the main surface of guide track 101 decreases between each respective cutter block encountered during rotation of the securing means.

For example, cutter block 113 is located at an initial position such that the main longitudinal axis of cutter block 113 is positioned at an average height of 200 mm above guide track 101 main surface. The next adjacent cutter block 115 being located at a height of approximately 198mm above guide track 101 main surface, each adjacent cutter block encountered in the same rotational direction being located 2mm closer to the main surface of guide track 101 such that cutter block 114 is located at a height of approximately 186 mm from guide track main surface 101. Where each cutter block comprises a cutting edge configured to produce a shaving of 2mm thickness. The result of passing a quantity of wood past each cutting element is to shave a maximum of approximately 16 mm from the quantity of wood, producing a plurality of shavings each of approximately 2mm thickness.

Further referring to figure 1 herein, there is specifically illustrated fourteen securing means 103 each configured to securely mount a quantity of wood for presentation to the set of cutting blocks. Where each cutting block is set to produce 2mm shavings a single rotation of the rotary table 107 enables a maximum reduction of each quantity of wood by 16mm by the production of 2mm depth wood shavings.

By adjusting the length of cutting edge exposed for engagement with a quantity of wood, optionally in combination with further adjustment of the height of each cutting block from the main guide track 101 surface, a variation in thickness of wood shavings produced can be achieved. Typically, this range is in the region of 0 to 10 mm but wood shavings of greater depth could be produced by varying the dimensions of the cutting edge as well as speed of rotation of the cutting block to ensure smooth cutting.

A universal motion controller or a sensing means (not illustrated in fig. 1) comprising a proximity switch operates to-detect the completion of a single rotation of rotary table 107. Upon detection of a single rotation a control means operates to halt rotation of rotary table 107 typically such that the securing means stops in a position away from the cutting elements 110, as illustrated in fig 1. Further, the control means acts to automatically adjust the height of each cutter block from the main surface of guide track 101. The control means comprises a processor in the form of a digital computer for monitoring and controlling operation of the apparatus of the present invention. The height of each cutting element 110 above the main surface of guide track 101 is variable and controllable to adjust said height between sweeps of the securing means 103 caused by rotation of rotary table 107.

Referring to fig. 2 herein, there is illustrated an enlarged diagrammatic view of part of the apparatus for controlling the height of the cutter blocks 110 from the main surface of guide track 101. Each cutter block 203 is mounted on a spindle 211, the spindle further mounted at a housing 204 by bearings 212. Heavy duty

construction of the housing 204 supporting the drive motor 206 ensures vibration free operation. A flat belt drive system connecting the drive motor 206 to the spindle 211 assists in reducing vibrations.

Each cutting element 203 is supported by a separate housing 204 and driven by a separate drive motor 206. The combined assembly of housing 204 and drive motor 206 is vertically movable by a linear actuator means or lead screw 207. Each linear actuator or lead screw 207 is controlled by a shaft 214 connected at one end to the linear actuator or lead screw 207 by a worm reduction gear box 216. Shaft 214 is connected, at an end distal to the lead screw 207, to a servo or stepper motor 215 (illustrated in exploded view) configured to drive rotation of shaft 214. Rotational movement of shaft 214 is converted to vertical movement to adjust the height of cutter block 203 via the worm reduction gear 216 driving rotation of the linear actuator or lead screw 207.

Housing 204 is attached to a moveable linear block 217 and can thereby be moved vertically up or down towards or away from the guide track 101. The servo or stepper motor 215 is adapted to be controlled by a motion controller as illustrated in fig. 8.

Accordingly, each cutting element is adjustable providing for each cutting element to be set up at the beginning of the wood shaving operation at a different depth of cut to that of the adjacent cutting element. For example, the first cutting element may be set up to reduce the stock by 2mm, the second by a further 4mm, the third by a further 5mm, the fourth by a further 2mm, etc. Once the user has defined the cutting element setup the control means calculates the total reduction of stock by conversion to wood shavings per sweep and informs the user.

Each cutting element is further mounted on a plurality of moveable linear blocks 218 which provide for an equal height adjustment of all of the cutting elements after each sweep. A frame 209 is provided upon which the height adjustment mechanism is mounted. A further linear actuator or lead screw 208 is

configured to allow moveable linear blocks to move vertically up or down, thereby moving the cutting element attached to it. A shaft 201 is further provided connecting each linear actuator or lead screw 208 of each cutting element, the shaft being separated by one or more universal joints 205 enabling the linear sections of shaft 201 to extend around the non-linear circular track thereby connecting each cutting element and linear actuator or lead screw 208 for the adjustment of each cutting element. The plurality of linear actuator means 208 and the connecting shaft portions 201 provide a universal mechanism of synchronously controlling the relative heights of the plurality of cutting elements from the main surface of the guide track 101. Rotational movement of shaft 201 is converted to a vertical movement by a plurality of worm reduction gearboxes 210, each of which connect a portion of the shaft 201 to each linear actuator or lead screw 208. Rotational movement of shaft 201 is driven by a servo or stepper motor 213 which is further adapted to be controlled by a control means.

Shaft 201 is supported by a plurality of self-aligning bearings 219 mounted on frame 209 (part of the frame is not illustrated).

Detection of a completion of a single sweep by a proximity switch or by monitoring of the position of rotation of the rotary table activates drive means 213 to rotate shaft 201 causing the plurality of worm reduction gearboxes 210 to rotate by predetermined amounts thereby adjusting each of the plurality of linear actuator or lead screw mechanisms 208. This causes the plurality of mounting blocks 218 to be adjusted by a predetermined amount thereby raising or lowering the height of each of the plurality of cutting elements by an equivalent amount.

This predetermined change in level of the plurality of cutting elements is adjustable by the user programming the control means such that a desired number of sweeps will reduce the stock secured in the securing means to a required level.

Each cutter block and motor assembly 206 is adjustable in height by using the linear guide actuator systems described above. The individual linear guide

actuator systems 207 are controlled by servo or stepper motors 215 connected individually to a control means. The control means forms a mutli-axis motion controller capable of solving both basic and complex motion control applications. At any given time the control means can determine the position of each stepper motor as the number of steps in the adjustment mechanism can be stored. Accordingly, a determination of the depth of each cut for each cutter block can be made. A visual reference point is applied to each cutter block housing so that the movement of each cutter block 203 can be monitored by the operator by measuring the height of each cutter block 203 against an approved scale marked on a visually clear plate (not illustrated) on the housing 204.

The main shaft 201 linking each motor assembly and cutter block has the ability with the corresponding main linear guide actuator system 208 to adjust the height of the combined number of cutter blocks collectively and as one. The main shaft 201 forms an axis controlled by a servo or stepper motor 213, further controlled by the control means. Further reference points are applied to the universal height adjustment mechanism of the collective assembly by provision of a further visually clear plate (not illustrated) having an approved scale on the main frame 209.

Following a single sweep of the rotary table 107 and following detection of the end of the sweep by the servo or stepper motor (not illustrated) connected to the control means, the control means momentarily stops rotation of rotary table 107. When movement has ceased, the control means act to rotate shaft 201 by a separate servo or stepper motor 213. Rotation of shaft 201 is communicated between each cutting element by a plurality of worm reduction gearboxes 210 transferring rotational movement of shaft 201 to a vertical rotational movement of the plurality of linear actuator or lead screw mechanisms 208. This movement in turn causes an adjustment of the moveable mounting block 218 relocating the respective cutting element and cutter block 203 to a different height from the main surface of guide track 101. The control means then reactivates movement of rotary table 107 to cause a further sweep.

Accordingly, each cutting element is simultaneously adjusted in height by a predetermined controlled amount at the end of each sweep of the securing means so as to realign the cutting element in a suitable position to remove a further set of shavings from the material securely engaged in the securing means 103 during a subsequent sweep.

For example, having removed the maximum of 16mm in a first sweep, the control means acts to lower each cutting element by 16mm. In the case of the example described above, the first cutting block encountered during a single sweep being lowered to a height of 184mm and the last cutting element 114 encountered in a single sweep being lowered to a height of approximately 168mm from the main surface of guide 101. Having operated the cutting block height adjustment a second sweep can be automatically commenced to remove a second layer of wood shavings.

Referring to fig. 8 herein, there is illustrated schematically the layout of the control means, comprising a personal computer, laptop, Mackintoshs or the like 801 and a universal motion controller 802 connected to servo motor or stepper motor controller drivers e. g. the Compas range manufactured by Parker Automation which are configured to control servo or stepper motors 215 controlling the level of each cutter block at each housing 204 as well as servo or stepper motor 213 controlling the universal height adjustment mechanism and servo or stepper motor 805 controlling movement of the rotary table.

Suitable servo motors include the SV-S and SVHX-S series drives

TM manufactured by Parker Automation Suitable programmable control means for controlling the cutting element height adjustment mechanism and rotary movement of the rotary table (start and stop functions) is provided by utilsing fully digital servo technology. For example, referring to fig. 8 each servo or stepper motor is controlled by a suitable industry

standard servo or step and direction drive 803. Each drive 803 is designed to operate in conjunction with the servo or stepper motors using sinusoidal commutation and resolver feedback. The servo or stepper drive 803 integrates functions of position, speed and current control within a fully digital system. The servo or stepper drive 803 can be controlled using direct commands in real time from a host controller, or can operate from the internally stored control program.

Selectively, each servo or stepper drive 803 is linked to a universal motion controller 802, for example one or more 6K motion controllers manufactured by Parker AutomationTM. Universal motion controllers such as the 6K are multi-axis controllers capable of solving both basic and complex motion control applications.

In combination with suitable support software, e. g."motion planner", a rapid setup and seamless integration of detected and output control functions is provided for. The operator can manually instruct commands via computer 801 which further enables observations of the status of the system.

A servo or stepper motor 805 controlling the rotational movement of the radial arms is connected to the control means and programmed to stop momentarily on each revolution so that the adjustments can take place to the linear guide actuator mechanisms described above.

In summary, once programmed, a control means in the form of a computer processing unit controls the overall operation of the positional elements (the linear guide actuators/lead screws) so as to shift each machine cutting element on its individual machine axis from one pre-determined setting to another. The control means is configured to identify the machine axis to which the positional element is at any time connected and to store and display that information to the operator. In use, the positional elements are connected to the cutting element adjustment elements such that information is fed to the control means to identify each particular element and the control means comprises a memory portion retaining information regarding the last position of a particular positional element.

By suitably programming the control means the operator is able to instruct the control means to adjust the setup of the machine e. g. to adjust the height

adjustment between sweeps of the securing means. The control means controls and implements this adjustment in order to adjust the cutting elements for alignment in the new setup position. This new position is then stored in the memory portion of the control means.

Whilst the number of cutting elements, circumference of the guide tracks and number of securing means can be varied, for the specific embodiment illustrated in figures 1 and 2, rotation of the securing means at 20m/min, wherein the exterior guide track 101 has a circumference of 9.42m produces approximately 2.1 revolutions per minute. For the example given above, to reduce 160mm of wood entirely to shavings would require 10 revolutions. Where each brief halt in the shaving cycle to cause cutter height adjustment takes 15 seconds then reduction of 160mm of wood to shavings using eight cutter blocks, each shaving 2mm per block, can be undertaken in under 7 minutes. As shavings are produced they are extracted, typically by a suction extraction means, and processed for baling.

Referring to figure 3 herein there is illustrated diagrammatically in perspective view one example of a cutting element 300 suitable for use in the first embodiment of the present invention. Various types of cutting elements are known to be used for planing wood in the prior art and any such cutting element capable of producing wood shavings from a quantity of wood passed by a cutting edge on such a cutting element could be used in the apparatus of the present invention. Referring to figure 3 there is illustrated a substantially cylindrical cutting element 300 comprising 2 cutting edges/blades 301,302, each cutting edge extending along a main length of the cutting element 300. A spindle 303 is provided for engagement with a chuck portion of a driving mechanism to rotate the cutting element 300 about a main longitudinal axis extending through the centre of spindle 303.

Referring to figure 4 herein there is illustrated an end view of one type of cutting element suitable for use in the present invention. Figure 4 illustrates a

substantially cylindrical cutting element 400 of a type similar to that illustrated in figure 3 and comprising three cutting blades, each blade 401 extending along a main length of the cutting element 400. Each blade is evenly offset at 1200 spacings.

Referring to figure 5 herein there is illustrated an enlarged perspective view of a securing means according to the first embodiment of the present invention. Securing means 500 comprises a base member 501 typically manufactured from metal or plastics material. Base member 501 comprises a plate having guide grooves or rails 502 formed therein. A first end of the securing means 500 is formed into a first wall portion 505 and a second end of the securing means is formed into a second wall portion 508. In use second wall portion 508 is located at the exterior circumference of the main guide track 101. The underside of plate member 501 is formed to mount the guiding groove or rail 102 formed in the main guide track 101. Located between first and second wall portions is a third wall portion 507 mounted on guide groove/rails 502 and moveable thereon between first wall 505 and second wall 508. A quantity of wood placed between third wall portion 507 and second wall portion 508 is gripped by sliding third wall portion 507 towards second wall portion 508 wherein gripping projections 509 located on third wall portion 507 and the inner surface of second wall portion 508 (not shown) grip the quantity of wood to firmly secure the quantity of wood in position.

Third wall portion 507 is urged towards second wall portion 508 resiliently by a pneumatically or hydraulically powered extendable ram, piston or rod 506 extending from a pneumatic or hydraulic drive box 504. In the case where a pneumatic drive box 504 is utilised a compressed air line runs parallel to radial arm 503 towards rotary table 107 wherein a swivel joint provides a continuous supply of compressed air during rotation of the securing means. Compressed air supplied from a connected air compressor. Where a hydraulic drive box 504 is utilised, each securing means comprises an independent hydraulically powered ram for securing a quantity of material at the securing means.

An example of a suitable pneumatic cylinder is the series P1MTM Pneumatic cylinder range manufactured by Parker Cylinder.

Referring to figure 6A and 6B herein there is illustrated securing means of the second embodiment of the present invention. Figure 6A illustrates a side view cross section of the securing means according to the second embodiment of the present invention. The securing means comprises a first wall portion 604 and a second wall portion 603 connected by a first base member 601 in the form of a plate member extending between said first and second wall portions. Mounted upon said first base member 601 there is located a sealing member 602 comprising an endless sealing member formed in the shape of a polygon or ring.

Sealing member 602 is made of flexible material capable of forming a seal on contact with a surface layer, suitable materials comprising synthetic and natural rubbers and plastics. Located beneath first base member 601 in substantially parallel orientation and extending between first and second wall portions, is a second base member 611 defining a cavity between the first and second base members 601,611. Cavity 607 is connected to a line 600 through which air may flow. Line 600 is attached to radial arm 605.

Referring to figure 6B herein there is illustrated a plan view of the securing means of the second embodiment of the present invention. Plate member 601 comprises a plurality of apertures 612,611 surrounded by a perimeter ring of sealing member 602. Apertures in the base member 601 may be formed of varying shapes. Two examples are illustrated. The first example comprising circular apertures 612 and the second example comprising elliptical apertures 611.

As an option, pneumatic or hydraulic cylinders of a type described above and illustrated in figure 5 in respect of the first embodiment may be combined with the vacuum securing mechanism of the second embodiment.

By connecting lines 600 via swivel connections at the rotary table to a vacuum pump air can be drawn through apertures 612,611. Mounting of a mounting block 608 or quantity of wood 609 on the sealing member 602 and operation of the vacuum pump can be configured to create a vacuum between base member 601 and the base of mounting block 608. This vacuum securing material items in position for presentation to the cutting elements for production of shavings.

Securing means of a type according to either the first or second embodiment of the present invention provides for the loading and gripping of wood items for the production of shavings by presentation of the wood items to a series of cutting elements. In particular, in the first embodiment wall portions of the securing means are required to enable gripping of the wood items.

Accordingly, the greatest height of a wall portion limits the depth to which the cutting elements can be adjusted as to adjust the cutting elements to cut below such a depth would damage both the cutting elements and the securing means.

Directly loading wood items into such securing means would therefore produce a limited depth of wood waste material corresponding to the depth of wall portion used. In the second embodiment of the present invention this depth is negligible as it is only necessary to avoid contact of the cutting edge with sealing member 602. In the first embodiment of the present invention this depth is typically 6mm, such that a quantity of wood of approximately 6mm depth would need to be discarded as waste.

To overcome this problem it is an optional alternative to mount each wood off cut upon a separate mounting block 608 as illustrated in figure 6A. Mounting block 608 may comprise a rectangular quantity of mounting material, typically wood or plastics material. At least one waste wood off cut 609,610 is glued to the mounting block 608 by use of an appropriate adhesive in a pre-loading stage.

More than one off cut 609,610 may be glued together using adhesive to form a combined quantity of material of a height sufficient to maximize the efficiency of the apparatus by ensuring engagement of the wood material with the first cutting

element during the first sweep. For example, where the first cutting element is located at an initial position of 200mm above the main surface of the guide track 101, and wherein the distance from the main surface of the guide track to the upper surface of the mounting block 608 is 40mm, 10 sweeps past the series of eight cutter blocks, each block removing 2mm would reduce a quantity of wood material with a maximum height of 160mm entirely to wood shavings in 10 sweeps. Typically, the pre-loading time required for adhesive to set between mounting block and wood material is in the region of 1.5 minutes. This operation is performed in advance such that the loss of machine time incurred during the adhesive drying time is eliminated. At the end of the process the mounting block 608 is retained and can be reused.

There will now be described a first specific method of operation of the apparatus of the present invention with reference to figure 7 herein.

Wood waste off cuts are obtained from supply sources 701 and are either loaded directly to a securing means 703 or are initially adhered to a mounting block 702 for loading 703. To optimize the efficiency of the apparatus each securing means provided is loaded with a quantity of material from which shavings are to be produced. A check is made to see whether the cutting elements are located in an initial position 704. If the cutters are not in an initial position the operator instructs the processor to locate the cutters in a required predetermined position 705. The initial position of the collected cutter blocks is variable, dependent on the operator selecting the individual depth of cut. When the individual cutter blocks are positioned, the collective set of cutting elements are further height adjusted as necessary under control of servo motor 213 and shaft 201 in order to set each cutter block at a predetermined position. The control means is programmed to operate a series of sweeps, the first commencing 706 to produce wood shavings, which are collected 707 and processed for baling. The end of the first sweep is detected by a sensing means 709 comprising either monitoring of the position of the servo or stepper motor which controls movement of the rotary table or via a microswitch detecting

completion of a single sweep. Detection at the end of the first sweep stops movement of the rotary table and securing means 710. A check is made to see whether shaving is to be continued 711. If shaving has been completed the sweep cycle is ceased and the operator is informed that unloading the waste wood or mounting blocks may be performed 712. Where a second sweep is to be performed the cutters are automatically height adjusted to the next cutting height levels 713 and the next sweep is operated 706. After the final sweep, the mounting blocks are unloaded 712 and the shaving process is complete 714.

In use, the operational procedures of the apparatus of the present invention occurs as follows. Referring to Fig. 8, the operator inputs information to computer 801 e. g. the datum of the tallest piece of stock secured in a securing means. This datum can be the depth of stock measured in millimeters or another approved scale. Computer 801 comprises a memory portion storing information on the lowest point to which the cutter blocks can be safely set. Computer 801 is programmed not to permit the operator to set any of the cutter blocks below this bench mark. In one example, this bench mark is assigned a zero value and the datum of the tallest piece of stock secured in a plurality of securing means is assigned a maximum value e. g. 160mm. Computer 801 is programmed to inform the operator of the best option of reducing the stock to the bench mark level. Where wood shavings are required for animal bedding, it is known in the art that a 1 mm to 10mm thickness shaving would be of acceptable quality for animal bedding. Therefore the desired thickness for wood shaving is input to the computer 801 which calculates the best option of reducing the stock of 160mm in increments ranging from 1-10mm. The operator can further input to the computer 801 a desired thickness within this range. Computer 801 calculates the number of sweeps required to reduce the stock to the level of the bench mark and the cutter block adjustments required between sweeps. The computer thus calculates a required number of sweeps and cutter block interval adjustments between sweeps.

Once these calculations have been conducted and the operator inputs an approval command the computer 801 instructs the universal motion controller 802 to set the cutter blocks at an initial calculated position by actuating the linear guide actuators or lead screw mechanisms 207 via drive 803 and motor 215.

Each cutter block housing 204 comprises a separate linear guide actuator or lead screw 207 controlling the depth of cut of stock during each revolution of the respective cutting element. The initial position of the cutter blocks is further defined by commands from the universal motion controller 802 to adjust the linear guide actuators or lead screws 208 via drive 803 and motor 213 providing a universal adjustment mechanism. Accordingly, an initial position is set up such that the first cutting block 113 engages with the tallest piece of stock secured in one of the plurality of securing means. Following input of the start command from the operator the universal motion controller 802 activates servo or stepper motor 805 to commence rotation of the rotary table according to a predetermined program. After each complete rotation the rotary table stops at a defined point wherein the securing means 103 are clear of the cutter blocks for a duration long enough so that the universal motion controller 802 can automatically adjust the level of the cutter blocks by collectively rotating shaft 201 via motor 213. A second sweep is then commenced and the cycle repeated. This continues until the stock has been reduced to the bench mark level wherein the rotary table ceases movement and settles in a position with the securing means 103 substantially clear of the cutter blocks. The operator is informed of completion of the shaving process via computer display 801. Release of the residual waste or separate mounting blocks from the securing means controlled by the control means formed by computer 801 and motion controller 802. The securing means are then configured for reloading for the production of further wood shavings.

The loading step comprises loading of wood stock to each securing means.

Once loaded, the user instructs the control means that each wood stock may be gripped by activating an appropriate vacuum supply or operating the pneumatic/hydraulic cylinders to extend their rods and firmly grip the stock in accordance with either the first or second embodiments of the present invention.

Once the wood stock is gripped, the drive means operating the rotary table is activated to begin its cycle and the wood stock is moved in order to engage with each rotating cutter block.

A suction extraction unit is employed to collect and transport the wood shavings produced into a storage area for further processing.

After a first complete revolution of the radial arms, the drive means operating the rotary table momentarily stops and immediately after cessation of rotational movement of the rotary table the control means activates the preprogrammed adjustment of the cutter blocks, consequently dropping the cutter blocks to their new cutting position. The rotary table drive means is then reactivated and another complete revolution of the radial arms is operated. This cycle continues until the stock is reduced in size to the lowest pre-determined cutting level. This level determined by the lowest cutter block ensuring that it does not engage with the gripping mechanism. After the final revolution of the radial arms the drive means operating the rotary table stops with all securing means in a position safely away from the cutter blocks. The gripping mechanism operated with the securing means is released and the mounting blocks or waste wood material is removed. A second operating cycle can then be commenced.

In order to reduce the quantity of wood stock which has to be discarded as waste it is advantageous to mount the stock on a dimensionally pre-determined feed block or mounting means which fits the gripping mechanism of the securing means to provide a uniform and level surface for mounting of the wood stock.

The uniformity of the mounting means provides a precision base level so as to enable pre-programming of the control means to ensure that the cycles of operation stop before the cutting blocks engage with the securing means.

Referring to fig. 9 herein there is illustrated a further embodiment of the guide track 101 and securing means 103 of the present invention. Each quantity of wood stock engaged in the securing means engages with the cutting elements

during rotation of the securing means causing a momentary upward force to pull the securing means and wood stock towards the cutter block as a result of the rotation of the cutter block. In a first securing means embodiment a groove or rail is provided to locate this securing means and counteract this upward movement.

In a further securing means embodiment as illustrated in fig. 9 track 101 comprises a slot 102 extending around the track to from a circular track. Each securing means 103 comprises a projecting portion in the form of a strut 901 extending from the base portion 502 downwardly through slot 102. Strut 901 provides for mounting of an axle 902 extending transversely from strut 901 and substantially parallel to track 101. At least one movement member 903 comprising a wheeled system e. g. rollers or bearings is provided attached to axle 902. Fig. 9 illustrates two rollers 903, one roller disposed at either end of axle 902 and mounted by a bearing. Rollers 903 are fittedly engaged (a gap is shown in Fig. 9 for clarity) in recessed grooves 904 located on the underside of track 101 and extending around the circumference of the underside of track 101. Rollers 903 engage in recessed grooves 904 which provide a guide surface defining the movement of securing means about the guide track 101 and limit the upward movement of the securing means.

In use, wood stock gripped in the securing means is pulled upwards towards the cutting element on encountering the cutting element. This upward movement is counteracted by urging of the roller members 903 into the guide track 101 which prevents further upward movement. The firmly gripped wood stock is therefore retained in this securing means throughout passage under each cutting element.

The present invention provides an apparatus and method for working a plurality of non-uniformly sized materials to produce shavings of the materials.

By arranging each material item at adjacent securing means and passing the adjacently held items past a series of cutting elements in rapid succession the effect is to have formed a single working length of material from a plurality of waste items.

The present invention is not limited to guide tracks of circular form. In alternative embodiments guide tracks of linear form or elliptical form can be provided wherein each securing means is mounted directly upon the main guide track, movement of one or a plurality of the securing means powered by a movement mechanism e. g. a geared movement mechanism located directly beneath the guide track to engage each securing means and move each securing means along the guide track past the cutting elements. In the case where a linear guide track is used a forwards and reverse motion can be provided to repeatedly pass the securing means past the series of cutting elements.

Adjustment of the apparatus of the present invention is not limited to movement of the cutting elements or their housing. One optional alternative is to maintain the cutting elements at a predetermined position between sweeps of the securing means, whilst providing a mechanism for raising the guide tracks 101,106 towards the cutting elements. By raising the guide tracks by variable intervals, the wood stock mounted in the securing means can be reduced in size in a controlled manner. Importantly the spacing between the guide track 101 main surface and the cutting elements is both variable and controllable. Combinations of moveable guide track surfaces and cutting elements provide further optional alternatives within the scope of the invention.

In a further optional arrangement, each securing means 103 is maintained in a substantially stationary position, each cutting element 110 moveable in a path such as to pass each cutting element past each securing means enabling engagement of each cutting element 110 at the wood stock gripped in each securing means for production of wood shavings.

The invention is further not limited to production of wood shavings of quantities of wood. Shavings may be produced from any material which can be cut using a sharp blade presented to the material. For example, plastics materials may be shaved in this way.

The invention is further not limited to production of wood shavings for use in animal bedding only, wood shavings produced by the apparatus and methods of the present invention suitable for use in various applications including production of wood pulp for use in manufacture of paper, cardboard and other paper based products.

Claims

Claims :

1. Apparatus for the reduction in size of a quantity of material by the production of shavings of said material, said apparatus comprising: at least one securing means and at least one cutting element, said at least one securing means configured to grip a quantity of material for presentation of said material to said at least one cutting element, wherein one of said at least one securing means or said at least one cutting element are moveable relative to the other to pass said quantity of material past said at least one cutting element, thereby presenting said material to said cutting element in order to produce at least one material shaving, wherein said apparatus is configured for adjustment of the spatial relationship between said cutting element and said securing means so as to permit production of material shavings from said quantity of material during a subsequent presentation of said quantity of material to said cutting element.

2. Apparatus as claimed in claim 1, wherein each said securing means is mounted on a guide, said securing means moveable past said cutting elements.

3. Apparatus as claimed in claim 2, wherein said cutting elements are mounted above a section of said guide.

4. Apparatus as claimed in claim 2 or 3 said apparatus comprising a plurality of cutting elements arranged consecutively along a section of said guide.

5. Apparatus as claimed in claim 4, wherein each said cutting element comprises a substantially cylindrical body having at least one cutting edge

extending from said body, said cutting element rotatable about a main longitudinal axis to present said cutting edge to a quantity of said material in order to engage said material and produce a shaving of said material.

6. Apparatus as claimed in claim 4 or 5, wherein adjacent said cutting elements are arranged such that the vertical displacement between a said cutting element and said guide varies between adjacent cutting elements.

7. Apparatus as claimed in claim 6, wherein adjacent cutting elements are arranged in order of decreasing size of said displacement.

8. Apparatus as claimed in any of claims 1 to 7, said apparatus further comprising a sensing means to detect passage of said securing means past said cutting elements.

9. Apparatus as claimed in any of claims 2 to 8 further comprising means to adjust the displacement of said cutting elements from said guide.

10. Apparatus as claimed in claim 9, wherein said means to adjust comprises means to adjust the displacement of all of the cutting elements simultaneously and separate means to individually adjust the displacement of individual cutting elements.

11. Apparatus as claimed in claim 9 or 10, wherein upon detection of passage of a said securing means past said cutting elements, the displacement of each of said cutting elements from said guide is automatically adjusted.

12. Apparatus as claimed in claim 11, adjustment of said displacement comprising lowering of said cutting elements towards said guide, each said cutting element lowered by an individual pre-determined amount.

13. Apparatus as claimed in claim 11, wherein adjustment of said displacement comprises raising said guide towards said cutting elements.

14. Apparatus as claimed in any of claims 8 to 13, wherein said apparatus further comprises a control means, said control means receiving information from said sensing means and operating to automatically adjust said displacement upon detection of passage of a said securing means past said cutting elements.

15. Apparatus as claimed in any preceding claim, wherein said securing means comprises a plate member configured for location of a said quantity of material and a gripping means to grip said quantity of material.

16. Apparatus as claimed in claim 15, wherein said plate member comprises at one end a first wall portion, said gripping means comprising a second wall portion urged resiliently towards said first wall portion and configured to trap a quantity of said material there between.

17. Apparatus as claimed in claim 16, wherein said securing means comprises a pneumatically or hydraulically powered ram causing said second wall portion to be urged towards said first wall portion.

18. Apparatus as claimed in claim 15, wherein said plate member further comprises a sealing member formed on said plate member and defining a polygon or ring, a plurality of apertures formed in said plate member within the area defined by said polygon or ring.

19. Apparatus as claimed in claim 18 wherein said securing means is connected to a vacuum pump configured to draw air through said apertures, a said quantity of material placed over said sealing member thereby retained in position by said vacuum.

20. Apparatus as claimed in any of claims 2 to 19, wherein said guide comprises a first circular track, a plurality of said securing means mounted upon said track, each said securing means connected to a rotary member positioned at the centre of said track by a radial arm extending from said rotary member to a respective said securing means.

21. Apparatus as claimed in claim 20 wherein said rotary member is operable via a control means and drive means for controlled rotation of said rotary member, radial arms and securing means.

22. Apparatus as claimed in claim 20 or 21, further comprising a second circular guide located between said rotary member and said first circular track, adjacent said radial arms connected by spacer elements, wherein at least one said radial arm is mounted upon said second circular guide.

23. Apparatus as claimed in any of claims 2 to 19, wherein said guide comprises a radial arm connected to a rotary member and said securing means and extending there between, rotation of said rotary member causing movement of said securing means.

24. Apparatus as claimed in any of claims 2 to 19, wherein said guide comprises a track comprising a slotted portion, said securing means further comprising a projecting portion configured to extend through said slotted portion, said projecting portion further configured to prevent substantial lifting of said securing means from said track.

25. Apparatus as claimed in claim 24, wherein said securing means further comprises at least one movement member engageable at a portion of the underside of said track to further define movement of said securing means.

26. Apparatus as claimed in any preceding claim wherein said material is wood.

27. Apparatus as claimed in any preceding claim configured for the production of wood shavings for use in animal bedding.

28. Apparatus as claimed in any of claims 1 to 26 configured for the production of wood shavings for use in the production of paper or cardboard.

29. Apparatus for the production of wood shavings from at least one quantity of wood, said apparatus comprising: a guide track; and at least one securing means moveably mounted upon said guide track, each said securing means configured to securely position a quantity of wood; and at least one cutting element mounted above a section of said guide track and arranged to contact said quantity of wood upon a first movement of said securing means along said guide track past said cutting element so as to produce at least one wood shaving therefrom, wherein, said cutting element position is adjustable to vary the displacement of said cutting element from said guide track so as to arrange a said cutting element to contact said quantity of wood upon a second said movement of said securing means.

30. Apparatus as claimed in claim 29, wherein said guide track is circular, each said securing means further comprising a radial arm extending from said securing means towards a rotary member located at a central position within said guide track, said radial arm fixedly attached to said rotary member, wherein rotation of said rotary member effects movement of said securing means about said track.

31. Apparatus as claimed in claim 29 or 30 wherein said apparatus comprises a plurality of said cutting elements arranged above a portion of said track, each said cutting element vertically offset from an adjacent cutting element such that a first said cutting element encountered during rotation of said securing means comprises a cutting edge contacting said quantity of wood at a position of greater vertical displacement to said guide track than the next adjacent cutting element arranged in the direction of rotation of said securing means.

32. A method for the reduction in size of a quantity of material by the production of shavings of said material comprising the steps of: loading a quantity of said material at a securing means said securing means gripping said quantity of material ; and moving said securing means and material past at least one cutting element to produce a material shaving; and adjusting the spatial relationship between said cutting element and said securing means; and moving said securing means and quantity of material past said cutting element so as to produce a second material shaving.

33. A method as claimed in claim 32, further comprising the steps of: sensing movement of said securing means past a said cutting element; and automatically adjusting said spatial relationship.

34. A method as claimed in claim 32 or 33 further comprising the step

of collecting material shavings and forming said collected shavings into a bale.

35. A method as claimed in claim 32, wherein said step of adjustment of said spatial relationship comprises lowering a said cutting element.

36. A method as claimed in claim 32, wherein said step of adjustment of said spatial relationship comprises raising said securing means.

37. A method as claimed in any of claims 32 to 36 wherein said material comprises wood.