TECHNICAL FIELD

[01] The present invention is directed to an improved tyre cutting apparatus which can cut the sidewails from tyres and which can cut other parts of the tyre - such as the tread portion. The term tyre or tire includes car tyres and truck tyres and may also include larger tyres such as those from small earthmovers and the like.

BACKGROUND

[02] Old tyres can be processed in a variety of ways to provide new products. These can include tyre crumb which can be used as a filler for asphalt or a cushioning material or noise deadening materiais. Oils and other solvents can be recovered from used tyres. The steel in tyres can also be recovered.

[03] The sidewails of a tyre are particularly sought after for recycling as the sidewails do not contain steel and is therefore the "purest" part of the tyre.

[04] Thus machines are known that cut the sidewails off a tyre for further processing. Some machines are extremely large, complex and expensive and contain hydraulic rams and other complex components.

[05] One aspect of the present invention is to provide a tyre cutting apparatus which is versatile and useful but that does not require expensive hydraulic rams and the like. Such an apparatus would find greater acceptability in smaller workshops and the like.

[06] Even if a tyre is not recycled but is instead send to landfill, there is an advantage in removing the sidewails and cutting the remaining tread into strips prior to disposal. [07] Cut tyres can be compacted together much more efficiently that uncut tyres meaning that a much greater number of tyres can occupy a given vo!ume of iandfiii. indeed the tyre volume can be reduced by about 70% by removal of the sidewa!is and cutting the remaining part of the tyre into one or more strips. Figure 2 illustrates the better stacking ability of cut tyres.

[08] Simpler machines are known that can remove the tyre sidewa!is. One example is given in my earlier Australian patent 725177. This machine uses a simple electric motor to drive a drive wheel containing a clamped on tyre cutting disc blade. A manually operated lever system is used to push the tyre into the cutting wheel. The drive wheel (to which the cutting blade is clamped) has a toothed or profiled edge which is urged against the tyre. The motor drives the drive wheel which needs to contact the tyre with sufficient force to rotate the tyre into the cutting biade. A disadvantage with this machine is that the lever system needs to be preset and then locked so that the drive wheel is sufficiently pushed against the tyre. In practice, the sidewalS thickness of car tyres can vary and there will certainly be a variance between car and truck tyres, if the iever system is set for one type of car tyre and another tyre with a slightly thinner side wall is used, the drive wheei may not grip the tyre with sufficient force and the tyre can slip over the drive whee! - which is inefficient.

[09] To overcome this type of inefficiency, the cutting blade is formed with peripheral notches or cutouts. These function to grip the tyre and to pull the tyre into engagement with the biade portions which are between the cutouts. A biade may have 40 or more peripheral cutout portions and these reduce the cutting area of the disc Furthermore, the cutouts are susceptible to much greater wear and each corner or edge of the cutouts is prone to cracking or chipping.

[10] There would be an advantage to provide a tyre cutting apparatus which did not need a blade formed with peripheral cutouts and which instead could use a blade with a continuous smooth cutting edge. [11] Another disadvantage with many types of tyre cutting machines is that the machines can be damaged by any "kick back" that may occur if the cutting blade encounters metal in the rubber such as an embedded nail. Damage to the cutting blade can also incur. There would be an advantage to provide a Tyre cutting apparatus that can accommodate kick back to reduce damage to the apparatus.

[12] There would be an advantage if it were possible to provide a tyre cutting apparatus which could accommodate sidewalls which may have varying thickness and without needing to reset the machine every time.

[13] As mentioned above, machines are known that can remove or cut the sidewalls off a tyre. The remaining circular "tread" portion of the tyre is then cut by a guillotine or something similar such that it can be more efficiently stacked or stored. However, to date, it has not been possible or easily achievable to have a single apparatus that can remove the sidewalls from the tyre and can cut the remaining tread portion into strips or something similar. There would be an advantage if it were possible to provide a tyre cutting apparatus that could cut the sidewalls away from the tyre and which could also cut across the tread of the tyre. There would be an advantage if it were possible to provide such an apparatus that could achieve this in a simple manner and without large adjustments to the apparatus to enable both types of cutting to be performed.

[14] An object of the present invention is to provide a tyre cutting apparatus that may overcome at Ieast some of the above-mentioned disadvantages or provide a useful or commercial choice in the marketplace.

[15] Any references to methods, apparatus or documents of the prior art are not to be taken as constituting any evidence or admission that they formed, or form part of the common general knowledge. SUMMARY OF THE INVENTION

[16] According to a first aspect of the present invention there is provided a tyre cutting apparatus comprising a tyre rotating means adapted for contact against the tyre and to rotate the tyre, a tyre cutting means adapted to cut the sidewail off the tyre, the tyre rotating means able to rotate the tyre into cutting engagement with the cutting means, and a biasing means adapted to bias the tyre rotating means against a tyre to be cut.

[17] The biasing means can ensure that the tyre rotating means is always against the tyre with sufficient force to rotate the tyre and not to unnecessarily slip against the tyre.

[18] The biasing means can do away with the need for a "notched" cutting blade to assist in feeding the tyre into cutting engagement with the cutting blade, the disadvantages of this being described above. Thus a continuous non-notched (smooth) cutting blade can be used which is more efficient.

[19] The tyre rotating means may comprise a drive wheel which may have similarities to that described in my earlier patent 725177 and identified with reference numeral 24 in figure 1 at least in my earlier patent. Of course, the tyre rotating means need not be limited to features described in my earlier patent. Generally, the drive wheel will have a diameter of between 10-40cm and a width of between 2-10cm. This can of course vary to suit.

[20] It is not necessary to provide expensive hydraulic components to cut the tyre as the biased drive wheel is suited to rotate the tyre.

[21] The rim or periphery of the drive wheel is suitably provided with grip enhancing means to ensure a good grip with a tyre to be cut. This may be in the form of projections, knobs, teeth and the like on the rim. Alternatively, or in addition thereto, friction enhancing means may be provided such as a rubber type layer to frictionaily engage with the tyre. [22] The tyre cutting means may comprise a disc blade. Suitably, the disc biade is supported by the drive wheel. Suitably, the disc blade is clamped or otherwise attached to the drive wheei to project therefrom sufficiently to cut through the thickness of a tyre wall. Thus it is expected thai the blade will extend by a distance of between 1-5 cm from the drive wheel

[23] The drive wheel may comprise two halves between which the disc blade can be positioned with the two halves able to be fastened together to damp the blade.

[24] A drive means may be provided to drive the tyre rotating means. The drive means may comprise an electric motor, hydraulic motor, pneumatic motor, combustion engine and the like. Suitably, the drive means is part of the apparatus and not a separate component. The drive means most suitably comprises an electric motor similar to that described in my earlier patent. The drive means may be operationally coupled to a gearbox.

[2:5] Suitably, the cutting means is attached to the tyre rotating means such that the drive means can operate (typically rotate) both members together.

[26] The biasing means is adapted to bias the tyre rotating means against a tyre to be cut. Suitably, the tyre rotating means is supported by a support frame_and the biasing means biases the support frame (and therefore the tyre rotating means) against a tyre. This will be described in greater detail below.

[27] in one form, the biasing means may comprise at least one leaf spring. There may be circumstances where the biasing means may comprise a coil spring. The biasing means may comprise a resilient member such as a rubber or similar block and the like.

[28] A tensioning means may be provided to pre tension the biasing means. The tensioning means may comprise a stop member against which the biasing means is tensioned. [29] The support frame may support the drive means and the tyre rotating means. Suitably, the tyre rotating means comprises a drive wheel and the tyre cutting means is a disc blade attached to the drive wheel such that the support frame supports the drive means (suitably an electric motor), the drive wheel and the disc blade.

[30] The support frame may be hinged or otherwise moveable between a use (tyre cutting) position and a retracted free position, in the retracted position a tyre can be positioned for cutting, or a cut tyre can be removed from the apparatus. Suitably the support frame can hinge or pivot by about 90° between the use and free positions. A handle may be provided to enable the support frame to be moved manually. The handle can be adjusted to different "start" or "initial use" positions to accommodate different operators and operations.

[31] The support frame may comprise a portion which is operably associated with the biasing means. The portion may comprise a stop arm. The stop arm may contact the biasing means when the support frame is in the use position.

[32] The apparatus may include a guide to enable the tyre tread to be cut into strips, for instance, for easier disposal. The guide may comprise a projection on which the tyre can be supported. The projection may comprise a guide pin. The guide pin may be adjustably mounted relative to the apparatus. The guide pin may be supported by a guide support. The guide support may comprise a short tube.

[33] The apparatus may include a support platform to support a tyre to enable the tyre to be cut into strips. The platform may include a ledge. The platform may be adjustable mounted relative to the apparatus.

[34] BRIEF DESCRIPTION OF THE DRAWINGS [35] Preferred features, embodiments and variations of the invention may be discerned from the following Detailed Description which provides sufficient information for those skilled in the art to perform the invention. The Detailed Description is not to be regarded as limiting the scope of the preceding Summary of the Invention in any way. The Detailed Description will make reference to a number of drawings as follows:

[36] Figure 1. Illustrates a tyre with the sidewall removed.

[37] Figure 2. Illustrates the advantage of storing tyres that have been cut into strips.

[38] Figure 3. illustrates a front view of a tyre cutting apparatus.

[39] Figure 3A. illustrates an adjustable handle.

[40] Figure 4. illustrates the apparatus of figure 3 with an attached tyre.

[41] Figure 5. Illustrates part of the sub frame of the apparatus.

[42] Figure 6. Illustrates a close-up view of the drive wheel, disc blade and pressure wheel of the apparatus.

[43] Figure 7. Illustrates the drive wheel is attached to a support frame and in the cutting position.

[44] Figure 8. Illustrates the support frame in the swung away free position.

[45] Figure 9. Illustrates an underneath view of the apparatus illustrating the drive wheel and disc blade.

[46] Figure 10. Illustrates a schematic section view of the pressure wheel and particularly illustrating a tapered groove.

[47] Figure 11. illustrates a PRIOR ART arrangement of the drive wheel

14 and the pressure wheel 32.

[48] Figure 12. Illustrates an offset arrangement of drive wheel 14 and pressure wheel 32 according to an embodiment of the present invention.

[49] Figure 13. Illustrates the ability of the apparatus to cut through the tyre tread as well as the tyre side wall.

[50] Figure 14. Illustrates a handle or lever used to assist in tyre tread cutting. [51] Figure 15. illustrates schematically a side view of the tyre cutting apparatus.

[52] Figure 18. illustrates the use of an adjustable stand to enable larger tyres to be processed.

[53] Figures 17 and 18. Illustrate a first modification to the apparatus to enable the tyre tread portion to be cut into strips of various widths.

[54] Figures 19 and 20. Illustrate a second modification to the apparatus to enable the tyre tread portion to be cut into strips of various widths.

[55] Figure 21 Illustrates a tyre tread gripper in use

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[56] Referring initially to figure 1 and figure 2 there is illustrated cut tyres. Figure 1 illustrates a side wall 11 cut away from a tyre 10. Tyre 10 has a tread portion 12. Figure 2 illustrates the advantage of cutting the sidewai!s away from the tyre and also slicing the tyres such that the tyres can be much more efficiently stacked in a much more compact form.

[57] Figures 3-9 illustrate various parts of the apparatus according to an embodiment of the invention. The main parts of the apparatus are as follows and will be described in greater detail below. The apparatus 13 comprises a tyre rotating means which, in the embodiment, is in the form of a drive wheel 14 this being best illustrated in figure 7 and figure 9. The drive wheel sits "underneath" the apparatus and is therefore not visible in figure 3. The apparatus further comprises a tyre cutting means, which, in the embodiment, is in the form of a disc blade 15 which is illustrated at least in figure 7, figure 6 and figure 9. In the particular embodiment, disc blade 15 is attached to drive wheel 14. A biasing means is provided which, in the embodiment, comprises a leaf spring 16 which is illustrated at least in figure 7 and figure 8. A drive means is provided which, in the present embodiment, comprises an electric motor 17 part of which is illustrated in figure 3. The drive wheel 14 is supported by a support frame 19 part of which is illustrated in figure 5, figure 7 and figure 8. The support frame 19 can pivot by about 90° between a use position and a retracted free position. A tensioning means in the form of a stop member 18 is provided to pre-tension spring 16 and the stop member 18 is illustrated at least in figure 8. The support frame 19 has a portion which is operably associated with the biasing means and, in the embodiment, this is in the form of a stop arm 20 which is illustrated at least in figure 7 and figure 8. All these features will be described in greater detail below.

[58] Referring to figure 3, the tyre cutting apparatus 13 comprises a flat table 21 to support a tyre. The table is inclined at a fairly steep angle and is supported by a sub frame 22 which is best illustrated in figure 5. The sub frame 22 comprises strong steel members which consist of at least a pair of spaced apart parallel longitudinal members 23 and a number of cross members 24 to make a strong rigid unit. This unit is pivoted on a baseplate 25 by pivot 26. The frame is held at the desired inclined angle by a super structure 27 which is supported by a foot 28, The table 21 is positioned on top of longitudinal members 23 and cross members 24. Table 21 is not illustrated in figure 5 but is illustrated in figure 3. The table 21 contains a cutout portion 29 (see figure 3) through which a "superstructure" can project. The superstructure comprises a mast portion 30 (see figure 5} and an arm member 31 is attached to an upper part of the mast and extends at right angles therefrom. The end of arm member 31 supports a rotatable pressure wheel 32 which is similar to that described in my earlier Australian patent. The pressure wheel 32, in use, is on the inside of the tyre (see figure 4). Pressure wheel 32 contains a circumferential groove 33 which is tapered from a wider opening to a narrower rear portion (see figure 10). The function of groove 33 will be described in greater detail below but briefly accommodates the disc blade 15 in use, an example of which is illustrated in figure 6.

[59] The tilt angle of the table allows for side loading of tyres as opposed to the conventional front loading. Processing efficiency is also improved by side loading. [60] Referring again to figure 5, one of the longitudinal members 23 supports a rotatable shaft 34 which can be seen as a pivot. The support frame 19 (which supports at ieast the drive wheel 14} is pivot!y attached to the shaft/pivot 34 through bearings 36. In figure 5, the drive wheel 14 has been removed from support frame 19. The bearings are more clearly illustrated in figure 8. The support frame 19 can rotate or pivot about 90°. Referring to figure 3 and figure 4, the "superstructure" (that is the mast portion 30, arm member 31 and pressure wheel 32) extend above table 21. Attached to arm member 31 is a second smaller arm member 37 which supports a small rotatable wheel 38. The function of wheel 38 is to prevent a tyre from slipping down the table because of the incline of the table. Figure 4 illustrates a tyre being held by contact on the inside of the tyre with small wheel 38 (wheel 38 not visible in figure 4). This arrangement is also illustrated in my earlier patent. Arm member 37 can be adjustably mounted relative to arm member 31.

[61] Reference will now be had to figure 7 which illustrates in greater detail the support frame 19. Support frame 19, as mentioned above, can hinge/pivot about pivot shaft 34 and is attached to the shaft by bearings 36. This is also illustrated in figure 8. The electric motor 17 (not illustrated in figure 7, but illustrated in figure 15) rotates a shaft 39 which is mounted for rotation in a bearing housing which is bolted to support frame 19 through mounts 40. Attached to the end of shaft 39 is the drive wheel 14. The disc blade 15 is attached to drive wheel 14. Specifically, drive wheel 14 can be separated into two halves and disc blade 15 can be clamped there between ( see figure 8). Drive wheel 14 contains an outer peripheral surface containing an array of grip enhancing means in the form of projection/teeth/knobs 41. These projections function to better grip a tyre.

[62] When the drive wheel 14 is pushed hard against the side wall of the tyre and rotated, this will cause the tyre to rotate. The tyre is trapped between the periphery of drive wheel 14 and the pressure wheel 32 (see figure 4) which is on the other side of the tyre. As drive wheel 14 contains the disc blade 15, this action will cause the blade to cut through the side wall, and as the tyre rotates, the entire side waif will be cutaway in the manner illustrated in figure 1.

[63] Figure 9 illustrates the position of the drive wheel 14 and disc blade 15 sitting beiow table 21. Figure 6 illustrates the relationship between the drive wheel 14, disc blade 15 and pressure wheel 32 and is a view from the front or top side of the table 21. Specifically, it can be seen that disc blade 15 projects from the periphery of drive wheel 14 sufficiently to cut through the thickness of a tyre side wall or a tyre tread. Pressure wheel 32 has a tapered groove 33 to accommodate the edge of blade 15. This ensures that the portion of the tyre that is trapped between pressure wheel 32 and drive wheel 14 is cleanly cut by blade 15. The projections 41 on drive wheel 14 are pressed into the tyre to rotate the tyre as the drive wheel rotates.

[64] An important part of the invention comprises the biasing means which will now be described in greater detail. In the particular embodiment, the biasing means comprises a leaf spring 16 (see figure 7 and figure 8). Leaf spring 16 is clamped at one end 42 to part of the sub frame 22. A small shim

43 is positioned between spring 16 and sub frame 22 such that the other end

44 of spring 16 is raised approximately 10-20 mm above the sub frame 22. The spring may be a fiat spring or may be curved for extra clearance and different characteristics.

[65] Spring 16 is pretensioned by a tensioning means in the form of stop member 18. Stop member 18 is best illustrated in figure 8. Stop member 18 comprises a steel L shaped member having a first leg portion 45A rigidly attached to the sub frame 22 and another other leg portion 45B extending over the other end region 44 of spring 16 but spaced above the spring by a small distance. A threaded bolt 46 can be inserted through a threaded opening in the leg portion 45B to vary the distance between the stop member 18 and spring 16. Lock nut 47 is provided to lock the threaded bolt in the desired position. In use, the threaded bolt is threaded such that the lower end of the bolt pushes down spring 16 and this can be seen as "pretensioning" of the spring. When the correct amount of pretensioning is achieved, the boit can be immobilized by the lock nut.

[66] The pretensioning is necessary so that spring 16 returns to the same spot and with the same pretensioning. This will be explained in greater detail below. The other advantage of pretensioning the spring is that the initial "springiness" of the spring is removed and this can assist in the initial punching of the blade through the side wail of the tyre to begin cutting. Without pretensioning, pushing the cutting blade into engagement with the tyre might simply cause the blade to be pushed back because of the initial "softness" of the untensioned spring. Pretensioning avoids this.

[67] The spring can be adjusted by replacing one type of leaf spring with a different type of leaf spring. The spring can also be adjusted by using different sized shims 43 (see figure 7) and at different positions.

[68] The support frame 19 is provided with a stop arm 20 which is illustrated in figure 7 and figure 8. Stop arm 20 is welded or otherwise rigidly attached to support frame 19. Stop arm 20 comprises an upper housing 48 having an internal threaded bore in which a threaded bolt 49 can pass. The bolt can therefore be extended from or retracted into housing 48 and, when in the desired position, can be locked in place by lock nut 50. This can adjust the amount of bias or force that the spring 16 produces on the support frame 19 - and therefore drive wheel 14.

[69] As mentioned previously, support frame 19 can rotate by about 90° from a cutting position illustrated in figure 7 to a swung away retracted free position illustrated in figure 8 ( allow a cut tyre to be removed or a new tyre to be placed in position). Figure 9 also illustrates the support frame in the cutting position and illustrates the support frame from the other side and therefore the spring 16 is not visible. When the support frame 19 is rotated into the "use" cutting position (figure 7), the bolt 49 on stop arm 20 rests on spring 16. Conversely, when the support frame 19 has been rotated by 90° and to the free position (figure 8), stop arm 20 has been rotated away from engagement with spring 16.

[70] When support frame 19 is in the use position (figure 7), spring 16 will bias or push against stop arm 20 which, in turn, pushes the support frame 19 and, as the drive wheel 14 and disc blade 15 are attached to support frame 19, these will be forced into engagement with a tyre to be cut. Thus, there is very little likelihood of the drive wheel 14 slipping against the tyre and therefore not properly rotating the tyre as spring 16 provides a constant bias against the tyre. Also, should the thickness of the tyre vary between tyres, the spring 16 will enable drive wheel 14 to adjust accordingly.

[71] The above arrangement ensures that spring 16 returns to the same spot and with the same pretensioning so that the stop arm 20 wili contact the same spot and the disc blade 15 will also stop in the same spot so that the preset relationship between the pressure wheel 32, the disc blade 15 and the drive wheel 14 remains accurate.

[72] The support frame 19 can be rotated about 90° between the use and the free position manually using handle 53 which is illustrated in figure 3. Handle 53 can be used to swing the support frame between the use and a free position. Handle 53 is illustrated as being fitted into a square socket 100A. Figure 3 illustrates three other square sockets 100B-D in the same general area and the handle can be slotted into any one of these sockets which has the effect of varying the angle that the handle extends from the remainder of the apparatus. Referring to fig 3A, the handle 53 can also be attached to a socket 101 which can be fixed at various angles by a spring loaded reciprocating pin 102 onto a backing plate 103 formed with an array of holes 104 for the pin 102 to locate in.

[73] Another significant advantage with the above arrangement is that it can act as an overload mechanism should the machine accidentally engage a foreign object like a bolt or nail inside the tyre. The overioad mechanism can cause a kick back which can be accommodated by spring 16 and therefore reduces damage to the rest of the machine by absorbing any sudden impacts.

[74] Referring to figure 10, there is illustrated a schematic cross-section view of pressure wheel 32 containing groove 33 and it can be seen that groove 33 is tapered. The taper assists with self-cleaning of rubber swarf as well as improving cutting of some rubber materials that are more elastic than others and therefore require different appearances.

[75] Another advantage of the embodiment of the present invention is in the "offsetting" of the drive wheel 14 relative to the pressure wheel 32. Referring initially to figure 11, this is a PRIOR ART schematic illustration of the lower drive wheel 14 sitting predominantly below table 21 and the upper pressure wheel 32. It can be seen that the pressure wheel 32 is positioned exactly above drive wheel 14. In this conventional arrangement, the intake or "nip" area 51 is relatively small. This means that the apparatus is generally not able to cut anything other than the relatively thin side wall of a tyre. Put differently, the apparatus is not able to also slice through the thicker tread area 12 (see figure 1) of the tyre. Conventionally, a separate guillotine or something similar is required to cut through the tread area 12.

[76] In contrast, in the particular embodiment, and referring to figure 12, the nip area 52 can be made significantly larger by offsetting pressure wheel 32 to be slightly forward of drive wheel 14. There are many ways in which this can be achieved however a simple way can be achieved by repositioning arm member 31 (see figure 3) to one side of mast portion 30 (see also figure 5). In this manner, the pressure wheel 33 becomes positioned slightiy forward of drive wheel 14. In conventional machines, arm member 31 is positioned exactly on top of a corresponding mast portion and therefore sits exactly above drive wheel 14, instead of the arrangement of the present embodiment where the arm member 31 is bolted or otherwise attached to one side of mast portion 30. [77] Consequently, the apparatus can be used to cut through the thicker tread portion of a tyre this being illustrated in figure 13, which would not be possible with an apparatus where the pressure wheel was not offset relative to the drive wheel. To cut the thicker tread portion 12 of the tyre, it is necessary to twist the tread portion to engage between pressure wheel 32 and drive wheel 14. As the tread portion may be quite stiff and difficult to twist, this can be assisted by handle 54 (see figure 14). Handle 54 can be pushed downwardly after the tyre tread has been loosely piaced in position (see for instance figure 4) and the tyre tread will contact the handle and continued pushing downwardly of the handle will force the tread into engagement with the disc blade 15.

[78] Figure 15 illustrates schematically a side view of the apparatus and particularly illustrates motor 17, drive wheel 14, pressure wheel 32, tyre 10, the mast portion 30, table 21 , and rigid leg member 62 (equivaient to 27 in figure 5), Rigid leg member 62 is mounted to a floor member 63 via a pivot 61. This apparatus is suitable for cutting tyres from cars and small trucks. However, if a larger tyre is positioned on table 21 , the lower end 64 of the tyre 10 can strike the ground 65.

[79] Figure 16 illustrates a modification to the apparatus of figure 15 to enable larger tyres to be cut. In the modification, an adjustable stand 60 is used to raise the lower end of the apparatus such that a large tyre 66 can now be cut without the lower end of the tyre striking the ground. As the apparatus is slightly raised, it will pivot about pivot pin 61. It is expected that the adjustable stand 60 will enable the apparatus to be raised anywhere between 10-50 cm. The adjustable stand has an upper "cup" type shape to cradle the lower end of the apparatus.

[80] Also, to assist in supporting larger tyres on the table 21 , rather than providing a much larger and heavier table, it is possible to provide an adjustable arm (not illustrated) extending laterally out from each side of the table to support a large truck tyre (for example). These arms may be adjustable in length and can be mounted for easy attachment and removal. It is also envisaged that the arms may be hinged between an extended use position and a swung away retracted position.

[81] Referring to figures 17 and 18, there is illustrated an adjustable guide for cutting the tyre tread into strips of desired width. These strips can be better compacted for landfill, or be further processed into such things a tyre derived fuel (TDF), accurately and consistently, more so than conventional shredders.

[82] The sidewal! of the tyre has already been cut off in the manner described above and the remaining tread portion 12 (see figure 1) has been cut once transversely across the tyre to open the tyre up.

[83] The adjustable guide as illustrated in figures 17 and 18 allows the opened up tread potion to be cut into longitudinal strips of different widths. The guide, in the particular embodiment, comprises short tubes 70, 71 which are welded to the side of arm member 37. In the embodiment, two tubes 70, 71 are illustrated, but more tubes may be present. A guide pin/bolt 72 can be inserted into a desired tube and guide pin 72 is of sufficient length to extend underneath a tyre tread 73 which is to be cut into strips so that the tyre tread can rest on the guide pin. As the tyre tread is cut into strips, the width of the strip will be the spacing between the guide pin 72 and the cutting disc blade 15 (which is as described above and which is on the other side of the tyre tread and therefore not visible in figures 17 and 18).

[84] Figures 17 and 18 illustrate a strip 74 being cut off tyre tread 73. To make the strip wider, the guide pin 72 can be removed from upper short tube 70 and inserted into lower short tube 71.

[85] Short tubes 70, 71 can be replaced with any other means for supporting a guide pin, and guide pin may comprise any type of projection.

[88] Figures 19 and 20 illustrate another type of guide to enable tyre strips to be cut. This guide is in the form of a platform assembly 80 which has a supporting ledge 81 on which the opened up tyre tread can be supported. The width of strip 74 cut off the tyre tread 73 is determined by the distance between supporting ledge 81 and the cutting disc blade 15 ( which is behind the tyre tread and therefore not visible, but is as described above). The assembly 80 is adjustably mounted to the table 21 , or other part of the apparatus to enable the distance between the supporting ledge 81 and the cutting disc blade 15 to be varied and thus the width of the cut off strip 74 to be varied. The assembly 80 can be adjustably mounted by any suitable means including the use of a pin in hole arrangement, a clamping arrangement and the like. The assembly 80 comprises two pieces which assemble on either side of pressure wheel 32 using RHS that slides inside each other.

[87] Figures 3, 14 and 21 further illustrates a tyre tread gripper 90 adjustably attached to the top side of the swing arm 54. Arm 54 can be swung about a pivot 91 to press the gripper against the tyre tread. The tread can be cut into pieces or blocks which can be useful as a fuel source. Figure 21 illustrates the tyre tread gripper 90 pressed up against the tyre 12.

[88] The apparatus is therefore quite versatile and can cut through tyres having varying thicknesses due to the ability of the drive wheel being "self adjustable" by being associated with the spring 16 instead of being locked in place. The continuous tensioning arrangement allows the relationship between the drive wheel, and pressure wheel to adjust to different circumstances and to different means. The disc blade 15 no longer requires slots to help in rotation of the tyre and the blade can now be entirely smooth blade. The smooth blade increases durability, reduces wear and improves performance. The tapered groove 33 on the pressure wheel assists with self- cleaning and improves cutting performance. The tensioning arrangement can accommodate any unexpected kick back that can be caused by a nail or bolt in the tyre without damage to the apparatus. The offset wheels provide extra clearance to enable cutting from different positions, and can also enable the tread portion 12 of the tyre can be cut by the same apparatus. [89] The apparatus as described above is a relatively compact and inexpensive machine that can be used by the businesses that generate tyre waste- such as tyre retailers and trucking companies - as opposed to large central tyre recycling organizations. This provides a small local solution to waste tyres. Instead of businesses needing to transport whole waste tyres to a central waste disposal station, the tyres can be processed on site.

[90] The construction of the apparatus is such that it can carry out various processing steps on tyres such as removal of the sidewali, cutting the tread into strips, cutting strips into blocks etc. All these steps can be carried out on site with a compact apparatus (about 1 cubic meter in volume) and the apparatus can be readily adjusted to suit different tyre sizes and to cut different sized strips and the like.

[91] In compliance with the statute, the invention has been described in language more or less specific to structural or methodical features. The term "comprises" and its variations, such as "comprising" and "comprised of is used throughout in an inclusive sense and not to the exclusion of any additional features. It is to be understood that the invention is not limited to specific features shown or described since the means herein described comprises preferred forms of putting the invention into effect. The invention is, therefore, claimed in any of its forms or modifications within the proper scope of the appended claims appropriately interpreted by those skilled in the art.

[92] Throughout the specification and claims (if present), unless the context requires otherwise, the term "substantially" or "about" will be understood to not be limited to the value for the range qualified by the terms.

[93] Any embodiment of the invention is meant to be illustrative only and is not meant to be limiting to the invention. Therefore, it should be appreciated that various other changes and modifications can be made to any embodiment described without departing from the spirit and scope of the invention.