TITLE DRILL CORE CUTTERS

[0001] This invention relates to drill core cutters.

[0002] The invention is concerned with a drill core cutter of the kind wherein a drill core is mounted on a support within a bath and a cutter is moved along the length of the drill core to make one or more axial cuts in the drill core either to split it into two hemi-cylindrical sections or into sections defined by two radial surfaces inclined to one another. Such a drill core cutter is hereinafter called a "submerged drill core cutter".

[0003] In our international patent specification number WO 2005/08 1624, there is described a submerged drill core cutter. In that submerged drill core cutter, the support is located within the bath, the support comprising two support surfaces, inclined to one another to form a "V"-shaped carrier on which the drill core is carried. In use, because of the turbulence of the water during the cutting, the drill core tends not to be firmly resting on the support and may move axially on the support. Furthermore, the support comprises two parts on which the support surfaces are respectively formed. By moving the parts towards and away from each other, the vertical position of the drill core may be adjusted. During the cutting of the drill core, a large amount of fines are produced. These will be spread out in the water to such an extent that the water becomes substantially opaque. Thus a workman may find that he cannot see the location of the support and may have difficulty in accurately placing the drill core thereon.

[0004] According to one aspect of the invention there is provided a submerged drill core cutter comprising a mounting device being capable of carrying a drill core, moving means attached to the mounting device and being operable to move the mounting device from an upper position which in use will be above the level of the bath and a lower position within the bath, and clamping means are arranged to act on the drill core when supported within the bath to hold it in position during the cutting operation.

[0005] There is preferably provided support means within the bath to which the mounting device transfers the drill core when moving into the lower position, and against which the clamping means clamps the drill core.

[0006] The mounting device preferably comprises an elongated mounting means on which the drill core will, in use, be placed. The mounting means preferably comprises a pair of vertical walls joined at their upper ends by the clamping means. The cutter preferably further comprises a removable carrier into which the drill core may be loaded and the mounting means comprises short mounting parts carried by the vertical walls on which mounting parts the ends of the carrier is supported. Thus the carrier may be loaded with a drill core, or a number of aligned drill cores, at a location remote from the drill core cutter, and then transported to the drill core cutter and mounted on the mounting parts at a position above the bath. The core is now lowered into the bath for the cutting operation and thereafter by moving the mounting device above bath the carrier can easily be seen and handled by a workman and removed from th& Gutter-.

[0007] The mounting means is preferably so arranged that as it moves downwardly into the lower position within the bath, the carrier engages the support means to be supported thereon, and in so doing is moved clear of the mounting means. On further downward movement of mounting device, the clamping means, which comprises a pair of elongated members that are separated by a gap through which the cutter passes to engage the drill core, engages the core(s) to force it against the carrier and the latter against the support. Thus the cutting operation can take place with the core in the bath mounting means preferably comprises lower means on which the mounting member rests and upper means which carry the clamping means.

[0008] An embodiment of the invention will now be described by way of example with reference to the accompanying drawings.

In the drawings: ~

Figures 1 and 2 are respectively a transverse and a longitudinal diagrammatic sections through a drill core cutter of the invention, and Figure 3 is an exploded perspective view of the mounting arrangement.

[0009] Referring now to the drawings there is shown a detail of a drill core cutter 10 which may (otherwise than as described herein) be as described and illustrated in WO 2005/08 1624. The drill core cutter 10 includes a support 100 for carrying a drill core 102 (or a number of aligned drill cores all referred to herein as "a drill core") within a bath 104 in an open topped housing 110 (shown only in Figure 1) which is traversed by a cutting blade 106 mounted on a cutter head 108 as described in the abovementioned-internationaLspecification.

[0010] The support 100 comprises a pair of support trapezoidal plates 112 joined by an elongated longitudinally extending member 113. The plates 112 have adjacent upper edges 114 and 116 of the support plates 112 are inclined to one another to form a "V-shaped support surface. There is a gap 118 between the edges 114 and 116 for the purpose which will be described. The support plates 112 are mounted on the piston rods 120 of jacks 122 which can lift the support plates 112 into appropriate positions (all within the bath 104) for the size of the cores to be cut and/or the depth of the cut.

[0011] The cutter 10 comprises a mounting arrangement 200 best shown in

Figure 3. The mounting arrangement 200 consists of a pair of end walls 202 joined at their upper ends by a clamping device 204. The clamping device 204 comprises a member which will be described more fully below comprising two parts 206 and 208 separated by a longitudinal gap 210. The end walls 202 each have a deep vertical slot 212 leading from the gap 2 10 and dividing the upper portion into two parts 212 and 214 which respectively carry the parts 206 and 208 of the clamping device 204.

[0012] On the insides of the end walls 202 are two inclined members 222 and 224 mounted respectively on the parts 212 and 214 to form "V-shaped carrier devices 226 the lower ends 228 of which are spaced apart. These devices 226 are aligned with one another.

[0013] The parts 206 and 208 of the clamping device 204 comprise curved plates separated by the gap 210. The inner part of each plate 206 and 208 has a vertical part 230 at the gap 210. These parts 230 engage the upper part of the core 102.

[0014] At the lower end of each end wall 202 is a robust outwardly directed flange 234. The flanges 234 are mounted respectively on the piston rods 236 of a pair of lifting jacks 238 to move up and down in synchronism from an upper position to a lower position. In the upper position of the mounting arrangement, the carrier devices 226 will be above the level of the bath. The lower position of the carrier device will be described below.

[0015] A removable mounting member in the form of a drill core carrier 300 is provided. The drill core carrier 300 is a shaped sheet metal part having a pair of diverging members 302 which lead into a generally hemi-cylindrical part 304 having a central mouth 306 which will be uppermost in the carrying position of the carrier 300.

Opposite the mouth 306 there is a narrow rectangular channel portion 308. The arcuate arms 310 of the hemi-cylindrical part 304 have short extensions 312 (of about 2 to 3 mm) which extend beyond the transverse diameter. The ends 314 of the extensions 312 are sharpened. The carrier 300 can be loaded with cores through the mouth 306. The base of the channel portion 308 has a row of closely spaced openings

(not shown) so that any water contained in the carrier 300 can drain therethrough.

[0016] The radius of the hemi-cylindrical part 304 is a millimetre or so greater than the radius of the drill core 102. It will be seen that the drill core carrier 300 is substantially identical to the drill core carrier of the first embodiment described in our co-pending patent application being filed to-day (Agents ref 94847.1). The loading of the carrier typically takes place as is described in the aforementioned patent application. Such loading takes place at a location spaced from the cutter 10.

[0017] The mounting arrangement 110 is located in the water bath 104 and aligned with the direction of movement of a cutter blade 106 which is carried for rotation on the cutter head 108. It is movable by the jacks 106 from an upper loading position in which the lower members 112 are above the upper surface 150 of the bath 104 to a lower position submerged in the bath 104 as shown in Figure 1.

[0018] In use, the jacks 122 are operated to adjust the position of the support plates 112 to the desired height for the core to be cut to the desired depth. The lifting jacks 238 now move the mounting device into its upper position. The drill core carrier 300 which was loaded at a remote location with a drill core 102 is brought to cutter 310 where its ends are placed in position on the mounting arrangement 200 being supported at its ends on the carrier devices 226. When so carried, the core carrier 300 will be in the carrying position with the mouth 306 of the hemi-cylindrical part uppermost between the end walls and with the ends of the hemispherical parts resting on the on the carrier devices 226. The channel portion 308 will perforce be in a lower vertical position. The core 102 will be exposed to the cutter blade 116. It will be noted that the core carrier will be above the level of the bath during this loading operation and the operator of the cutter will be able easily to see the location of the various parts for loading.

[0019] The jacks 238 now lower the mounting arrangement 110 to its lower position. When the mounting arrangement nears its lower position, the drill core carrier 300 engages the support plates 112 and is lifted off the carrier devices 226. Thereafter the carrier 300 is moved clear of the mounting means and is carried by the support plates-442-.— On-Gontinued downward-movement-of- the-mounting arrangement 110, the parts 206 and 208 of the clamping device 204 engage the drill core 102 and hold it

firmly on the support plates 112 through the intermediary of the drill core carrier 300. In this position the mouth 306 will be so located that the cutter blade 106 can pass therethrough during its traverse to cut the core 102. The blade 106 will move through the gap 210 and the slots 212 during its cutting traverse.

[0020] It will be understood that when the clamping device 204 engages the core 102, this will limit the downward movement of the mounting arrangement 110 by the jacks 238.

[0021] After the drill core 102 has been cut, and the cutting head 108 returned to an initial position, the jacks 238 will lift the mounting arrangement 110 to its upper position so that the drill core carrier 142 is located above the bath 104 and may be removed easily from the mounting arrangement. The process can then be repeated.

[0022] It will be seen that the drill core carrier 300 can quite easily be placed on and removed from the mounting arrangement when the mounting arrangement is in the upper position as all relevant parts are above the bath 104 and are clearly visible.

[0023] It will be seen that should the blade 106 pass through the core 102 it will be accommodated in the channel portion 308 and will be spaced from the base thereof.

[0024] As mentioned above, the drill core carrier 300 may be loaded with the drill core 102 at a location remote from the drill core cutter 10. All the foregoing will improve the operation of the drill core cutter.

[0025] The drill core cutter of WO 2005/081624 may be further modified by providing a diaphragm pump at the settling tank. The pump which will be intermittently operable, will deliver heavily loaded water to a concentration tank where it enters a filter bag. This will be periodically removed to dispose of the concentrated dust.

[0026] The drill core cutter may also be modified in that the cutter head 108 has modified moving means. The moving means consists of a rack extending along the length of movement of the cutter head. A pawl is driven by an ancillary motor carried by the cutter head and engages the rack so that on rotation of the pawl the cutter head is moved axially.

[0027] The operation of all parts may be controlled electronically by a processor so as to enable the drill core cutter to operate automatically.

[0028] The invention is not limited to the precise constructional details hereinbefore described and illustrated in the drawings. For example, the support plates 112 may be moved upwardly and downwardly by means of a threaded nut engaging on a threaded shaft carrying these parts. Apparatus is provided to rotate the nut thereby moving the parts upwardly and downwardly.