SUMMARY OF THE INVENTION According to the invention a cutting arrangement includes : a holder with a bore for a sleeve, the holder having a front face and a rear face; a sleeve with a bore for a pick, the sleeve having a head abutting the front face of the holder, a stem extending through the bore of the holder and a tail projecting beyond the rear face of the holder; a sleeve clip releasably secured to the tail of the sleeve to secure the sleeve to the holder; a pick having a head abutting the head of the sleeve, a shank extending through the bore of the sleeve, and a tail projecting beyond the tail of the sleeve ; and a pick clip releasably secured to the tail of the pick to secure the pick to the sleeve.

In the preferred form of the invention the tail of the sleeve has a circumferentially extending groove containing the sleeve clip.

The sleeve clip may consist of two semi-circular sections held together within the groove by a circlip.

The tail of the pick preferably also has a circumferentially extending groove containing the tail clip.

The tail clip may consist of the yoke located in the groove and held in the groove by a locking member which can be manually unlocked without the aid of a tool as opposed to the circlip which requires the use of a tool.

The sleeve is preferably rotatable within the bore of the holder, and the pick is preferably rotatable within the bore of the sleeve.

Preferably the clearance between the bore of the holder and the stem of the sleeve increases from the front of the bore to the rear of the bore. This may be achieved by the stem of the sleeve tapering inwardly towards its tail.

The clearance between the bore of the sleeve and the shank of the pick may increase from the front of the bore to the rear of the bore. This may be achieved by the shank of the pick tapering inwardly towards its tail.

According to another aspect of the invention a cutting arrangement includes a holder, a sleeve, and a pick, the sleeve being releasably secured to the holder by a sleeve clip, and the pick being releasably secured to the sleeve by a pick clip.

According to another aspect of the invention a cutting arrangement includes a holder, a sleeve and a pick, the holder having a bore within which a stem of the sleeve is located, there being a clearance between the stem and the bore, which clearance increases from the front of the bore to the rear of the bore.

According to another aspect of the invention a sleeve for a cutting arrangement includes a head and stem extending from the head, with the stem tapering inwardly towards its end remote from the head so that in use when the stem is located within the bore of a holder there is a clearance between the stem and the bore, which clearance increases from the front of the bore to the rear of the bore.

The stem may taper by between about 40 microns about 20 microns from its head end to its tail end.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a partly cut-away perspective view of a cutting arrangement according to the invention; Figure 2 is an enlarged view of part of figure 1; Figure 3 is a perspective view of the components of the sleeve clip ; and Figure 4 is a side view of a sleeve according to the invention.

DETAILED DESCRIPTION OF THE DRAWINGS A cutting arrangement 10 includes a holder 12 with a bore 14 for a sleeve 16. The holder 12 has a front face 18 and a rear face 20.

The sleeve 16 has a bore 22 for a pick 24. The sleeve 16 also has a head 26 which abuts the front face 18 of the holder 12, a stem 28 extending through the bore 14, and a tail 30 projecting beyond the rear face 20 of the holder 12.

A sleeve clip 32 secured to the tail 30 releasably secures the sleeve 16 to the holder 12.

The pick 24 has a head 34 abutting the sleeve 16, a shank 36 extending though the bore 22 of the sleeve 16, and a tail 38 projecting beyond the tail 30 of the sleeve 16.

A pick clip 40 is releasably secured to the tail 38 to secure the pick 24 to the sleeve 16.

The tail 30 of the sleeve 16 has a circumferentially extending groove 42 containing the sleeve clip 32. The sleeve clip 32 consists of two semi- circular sections 44 held together by a circlip 46. For the sake of clarity the circlip is omitted from figures 1 and 2 but shown in figure 3. The circlip 46 locates in a groove 48 formed in the two semi-circular sections 44.

The tail 38 of the pick 34 has a circumferentially extending groove 50 in which a yoke 52 of the pick clip 40 locates. The pick clip 40 has a locking member 54 moveable by hand between locked and unlocked positions.

The sleeve 16 is rotatable within the bore 14 of the holder 12, and the pick 24 is rotatable within the bore 22 of the sleeve 16.

The stem 28 of the sleeve 16 tapers inwardly from its head end to its tail end. Thus as can be seen in figure 4, the diameter indicated by reference numeral 56 is greater than the diameter indicated by reference numeral 58.

The difference in diameter is 20 microns. The tapering of the stem 28 results in a clearance or gap between the stem 28 and the bore 14 of the holder 12 which clearance increases from the front to the rear of the bore 14. Fine material known as fines can move through this gap. The increasing clearance has the effect of creating a pressure which decreases from the front to the rear, which decreasing pressure causes the fines to move from the front to the rear, and out through the rear.

The benefit of having the sleeve clip 32 and the pick. clip 40 is that if the pick clip 40 is dislodged from the pick 24 and the pick 24 falls out of the sleeve 16, the sleeve, which is more costly than the pick 24, is still retained within the holder 12 by the sleeve clip 32.

It will be appreciated that many modifications or variations of the invention are possible without departing from the spirit or scope of the invention.