GB2134424A

GB2134424A - A tile cutting machine

Info

Publication number: GB2134424A
Application number: GB08301793A
Authority: GB
Inventors: Clifton Edgar Ling
Original assignee: Individual
Current assignee: Individual
Priority date: 1983-01-22
Filing date: 1983-01-22
Publication date: 1984-08-15
Also published as: GB8301793D0; GB2134424B

Abstract

A machine suitable for cutting tiles comprises a box-like casing 10 in which is rotatably mounted an arbor 19 driven by a motor 16 through belt 15 at about 2500 r.p.m. The arbor carries a diamond dust cutting disc 29 which projects through a slot 28 in the top wall 14 of the casing, serving as a work-table. A water bath 26 is mounted within the casing so that from 6.25% to 6.75% of the disc diameter may dip into water contained in that bath. Suitable guides for a tile are provided on the top wall, whereby a tile may be slid along the guide whilst being cut by the rotating cutting disc. Water is picked up by the wheel to cool and lubricate the cutting edge, and forms a slurry with tile dust which runs back into the water bath through slots 32 and holes 31 (Figure 1). <IMAGE>

Description

SPECIFICATION A tile cutting machine This invention relates to a tile cutting machine. The term "tile" as used herein is intended to refer to all kinds of floor and wall tiles, including "soft" glazed tiles, ceramic tiles, earthenware and porcelain tiles, and quarry tiles. In so far as the machine may also be able to cut other materials, the term "tile" is moreover intended to extend to other such materials, including certain true ceramics, and also some kinds of pottery and earthenware, and glass. The term "tile" should therefore be construed accordingly, as the context so demands.

The conventional method for cutting glazed wall tiles and ceramic floor tiles is to score a line across the top face of the tile with a very hard, sharp tool, such as a pointed tungsten carbide scribe or a glass cutting wheel, and then to break the tile along the score line, typically by supporting the tile solely beneath the score line and applying downward pressure to the tile, on each side of that line. If only a relatively narrow strip is to be removed from a glazed wall tile or ceramic floor tile, or if a tile is to be cutto some special shape, the usual practice is to score the top face of the tile appropriately, and then to "nibble" away the unwanted material using a pair of pincer-like cutters.Unfortunately, cutting tiles by either of the above-described methods is not particularly reliable, and even with a skilled operator, the success rate can be relatively low, especially when a special shape is to be cut out of a tile.

For simple linear cuts, greater reliability can be obtained using a circular saw bench, but substituting the conventional wood-cutting saw blade by a bonded fabric/carborundum cutting wheel, and using the wheel either to produce a deep score in the top face of the tile along the line where the tile is to be cut, and then breaking the tile along that deep score line, or by actually cutting right through the tile, for the length of the required cut. However, there are several serious drawbacks resulting fom such a tile cutting process, including the fact that the wheel, the dust produced by the wheel and the tile itself in the region of the cut all reach very high temperatures, requiring the operator to wear protective clothing. moreover, the process generates an enormous amount of tile dust, which may be environmentally unacceptable.A further disadvantage is that the cutting wheel wears very rapidly, and hence the process is expensive to perform, in view of the cost of the required replacement wheels.

It is a principal object of this invention to provide a tile cutting machine which at least largely overcomes the various disadvantages mentioned above, of the described conventional tile cutting processes.

Accordingly, this invention provides a machine suitable for cutting a tile (as hereinbefore defined), which machine comprises the combination of a work-table having a slot in the surface thereof, a rotatable arbor mounted beneath the work-table and carrying a diamond dust cutting disc a portion of the periphery of which projects through the slot in the work-table, power drive means arranged to rotate the arbor and hence the cutting disc at a speed sufficient to permit the cutting of a tile thereby, and a water bath disposed beneath the cutting table and into which a lower sector of the diamond cutting disc projects to be able to dip into water contained in the water bath.

Though diamond dust cutting discs are known per se, for cutting a variety of materials as indeed are also circular saw tables, this invention nevertheless stems from the realisation that if a diamond dust cutting disc is incorporated in a saw table and is then provided with a suitable water supply, unexpectedly advantageous tile cutting characteristics may be obtained. This is believed to stem from the water serving to lubricate the cutting disc and also to keep the temperature of the disc and tile relatively low.

The water however moreover prevents the formation of clouds of tile dust, by binding such fine particles of the tile which are formed during cutting into a paste or slurry which remains in the immediate vicinity of the work-table itself.

Trials of the tile cutting machine of this invention have shown that the extent to which the disc dips into water contained in the water bath is important if the advantageous characteristics of this invention are to be optimized. If the amount by which the disc dips in the water contained in the water bath is insufficient, inadequate lubrication and cooling of the disc will occur leading to slow and ineffective cutting, and a shortened disc life, and moreover dust clouds are likely to form. On the other hand, if the disc dips into the water contained in the water bath to too great an extent, the operation of the apparatus becomes difficult in view of the fact that the work-table is likely to become flooded with water.

Empirical tests have shown that the advantageous result of the combination of this invention are achieved if the disc dips into the water contained in the water bath to at least 4% of the diameter of the disc, but to not more than 20% of the diameter of the disc. It is however preferred for the disc to dip into the water to at least 6% of the disc diameter, but not more than 10% of the disc diameter, with the most advantageous results being obtained when the disc dips into the water to between 6.25% and 6.75% of the disc diameter.

in the preferred embodiment of this invention, a cutting disc of approximately 150 mm (about 6 inches) diameter is employed, and the useful range of immersion of a lower sector of the disc in water contained in the water bath is from approximately 6 mm to 25 mm. The most advantageous results are however obtained if the discs dips into the water in the water in the water bath to a depth of substantially 10 mm.

Again, to optimize the tile cutting characteristics of the invention, the diamond dust cutting disc must carefully be selected from the range of such discs available commercially. The preferred embodiment of this invention employs a disc having a grit diameter of 80/100, a nominal diameter of 153 mm and a width of 1 mm. A suitable disc is manufactured by Diagrit Diamond Tools Limited and sold under the reference no. B 11851. The disc must be rotated at a rate sufficient for efficient tile cuting, and for the above-mentioned preferred arrangement, the disc is rotated at about 2500 rpm. At this rotational rate exellent tile cutting characteristics are obtained, it being possible to cut even very hard and relatively thick (up to about 25 mm thick) quarry tiles with relative ease.

It is preferred for the work-table to be provided with a plurality of apertures in the region of the slot through which the cutting disc projects, which apertures communicate with the water bath therebeneath. In this way, water carried on to the surface of the work-table may drain back into the water bath, taking with it such paste or slurry of the tile dust as been generated by a tile cutting operation. Conveniently, a plurality of slots are arranged generally perpendicularly to the slot, around the periphery thereof, and in addition a plurality of circular holes may also be provided, through the work-table, as appropriate. An alternative arrangement is to provide in the surface of the work table a pluraity of grooves, all leading to the slot through which the disc projects, so as to allow the drainage of liquid from the work-table surface back into the water bath.

Conveniently, a guide for tiles being cut is provided on the work-table, along which guide the tiles may be slid, whilst being cut by the diamond dust cutting disc. The guide should be fully adjustable relative to the position of the cutting disc, and conveniently a graduated rule is associated therewith, to facilitate the positioning of the guide.

Most preferably, the entire tile cutting machine is housed in a metallic casing, the work-table forming the top surface of that casing. The casing and water tank may be fabricated from aluminium sheets, in which case at lest the central region of the worktable and containing the slot through which the cutting disc projects preferably is faced with stainless steel to minimize wear as tiles are slid thereover during a cutting operation. The casing and/or the water bath could be manufactured in otherways-for example from a plastics material or a glass-fibre reinforced resin, though in such a case the worktable should still be made from or faced with a metal, to minimize wear.

By way of example only, one specific embodiment of tile cutting machine constructed and arranged in accordance with this invention will now be described in detail, reference being made to the accompanying drawings, in which: Figure 1 is plan view of the tile cutting machine of this invention; Figure 2 is a side view of the machine of Figure 1, partly cut away to show the interior details thereof; and Figure 3 is a vertical sectional view of the tile cutting machine, taken on line Ill-Ill marked on Figure 1.

Referring to the drawings, the tile cutting machine ofthis invention comprises a box-like casing 10, fabricated from six rectangular aluminium panels suitably joined together at their edges, for example by means of aluminium angle sections (not shown).

The casing thus comprises a base plate 11, side walls 12, end walls 13 and a top wall 14, serving as a worktable. The casing is divided internally into two sections by means of a dividing wall 15 (Figure 2) and in the smaller section of the casing produced by this dividing wall 15 there is mounted an electric motor 16 bolted to the base plate 11. Also provided within the smaller section of the casing is a control arrangement for the electric motor 15, the control arrangement including an on/off switch and a fuse, mounted within a water tight housing 17 attached to a side wall of the casing. Power cables 18 pass as appropriate through grommets (not shown) in the various walls, such that power may be fed to the electric motor 16, from an external electrical power source, via the control arrangement, when the tile cutting machine is to be operated.

Within the larger section of the casing created by the dividing wall 15 there is mounted an arbor 19 journalled in bearing block 20 having self aligningball races which bearing block is bolted to a shelf 21 suitably affixed within the casing to the adjacent side wall 12 and a further internal partition wall 22. At the end of the arbor 19 adjacent the side wall 12 there is provided a pulley 23, which is driven by means of a Vee-belt 24 from a further pulley 25 mounted on the shaft of the electric motor 16. The dividing wall 15 and the shelf 21 are cut away as appropriate, to allow the belt to pass around the pulleys 23 and 25.

Also mounted within the larger section of the casing defined by the dividing wall 15 is a water bath 26, which water bath is bolted to the base plate 11 of the casing and extends to just beneath the top wall 14 thereof. A rubber gasket 27 is provided around the top face of the water bath, to seal the bath to the lower surface of the top wall 14 of the casing 10.

Other than in the region of the gasket 27, the top of the water bath is open.

The work-table defined by the top wall 14 has a slot 28 formed along the longitudinal centre line of the top wall, as illustrated in Figure 1. Mounted on the end of the arbor 19 remote from the pulley 23 is a diamond dust cutting disc 29 of such a diameter that the disc projects through the slot 28. The position of the bearing block 20 and the diameter of the disc 29 are suitably selected such that the disc projects above the upper surface of the work-table by approximately 25 mm. A rectangular stainless steel plate 30 is riveted to the top wall 14 in the central region thereof, the stainless steel plate 30 having a slot corresponding in shape and size to the slot 28 in the top wall 14, the plate 30 being mounted so that its slot is in register with slot 28. A plurality of circular holes 31 are formed through both the stainless steel plate 30 and the top wall 14 therebeneath. Moreover, a plurality of grooves 32 are formed in the stainless steel plate, generally extending perpendicularly away from the slot 28, each groove having at its end nearer the slot a hole 33 formed through the stainless steel plate 30 and the top wall 14. Each of the holes 31 and 33 thus communicates through the top wall 14 to the interior of the water bath 26.

Brackets 34 project upwardly from each end corner of the casing 10, there being a rod 35 supported between each pair of brackets 34 respectively. Slidably mounted on each rod 35 is a boss 36, a guide bar 37 extending between and being affixed to the two bosses 36. The bar 37 may be locked in any desired position across the width of the worktable by means of screws 38 provided one in each boss 36 and serving to clamp the associated boss 36 to its rod 35. To facilitate the positioning of the guide bar 37, graduated rules 39 are affixed to the top face of the work-table, adjacent the ends of the casing, as illustrated in Figure 1.

A guard assembly is provided for the cutting disc 29 which assembly comprises a part-circular housing 40 affixed to the lower end of a rod 41 which passes through a bush 42 provided on an L-shaped arm 43. A screw clamp 44 is provided in the bush 42, whereby the height of the housing 40 may be adjusted relative to the top surface of the work-table.

The L-shaped arm 43 is mountd in a clamp 45, provided on a side wall 12 of the casing, adjacent one end thereof.

In this embodiment of the invention, the diamond dust cutting disc 29 has nominal diameter of 153 mm and an axial width of 1 mm. The cutting disc has an apparently relatively smooth periphery and smooth peripheral margins on the side faces thereof, but the disc periphery and a 5 mm wide peripheral margin of each side face carry bonded diamond cutting dust of a grit 80/100. A suitable cutting disc is manufactured by Diagrit Diamond Tools Limited, and sold under the reference no. B 11851.

The electric motor 16 is a 1/2 h.p. 1425 rpm single phase electric motor, and the motor shaft pulley 25 has a diameter of approximately 75 mm. The arbor pulley 23 has a diameter of approximately 45 mm, such that in operation, the arbor 19 and hence the cutting disc 29 rotate at approximately 2500 rpm.

Though not shown in the drawings, the water bath 26 may be provided with a drainage pipe, leading to the exterior of the casing 10 and provided with a tap, to facilitate the emptying of the bath. Moreover, a water supply pipe and level pipe may also be provided, if required.

In operation, the water bath 26 is filled with water to the required level and most preferably this is such that the lower 10 mm of the cutting disc 29 dips into the water contained in the water bath 26. Then, by turning on the switch of the control arrangement in housing 17, the cutting disc 29 will be rotated at the appropriate speed and tiles may be cut by being slid over the work-table surface, to be severed by the cutting disc 29. During this operation, the cutting disc picks up water contained within the water bath, this serving both to lubricate the cutting disc and to cool the disc and the tile in the region of the cut.

Moreover, such dust as is created by the cutting operation forms a slurry with that water, to drain back into the water bath 26, through the grooves 32 and the holes 31 and 33. If a simple linear cut is to be made on a tile, the guide bar 37 may be set at an appropriate position and then locked in place by means of the screws 38 in the bushes 36. However, the tile cutting machine of this invention may be used without employing the guide bar 37, and indeed tests have shown that it is possible to cut a variety of complex shapes out of a tile, simply by carefully sliding the tile over the work table, to be cut appropriately by the disc 29.

CLAIMS Filed on 19. 1.84 1. A machine suitable for cutting a tile (as hereinbefore defined), which machine comprises the combination of a work-table having a slot in the surface thereof, a rotatable arbor mounted beneath the work-table, and carrying a diamond dust cutting disc a portion of the periphery of which projects through the slot in the work-table, power drive means arranged to rotate the arbor and hence the cutting disc at a speed sufficient to permit the cutting of a tile thereby, and a water bath disposed beneath the cutting table and into which a lower sector of the diamond cutting disc projects for dipping into water contained in the water bath.

2. A machine according to claim 1, wherein the cutting disc dips into the water contained in the water bath to at least 4% of the diameter of the disc, but to not more than 20% of the diameter of the disc.

3. A machine according to claim 2, wherein the cutting disc dips into water in the water bath to at least 6% of the disc diameter, but to not more than 10% of the disc diameter.

4. A machine according to claim 3, wherein the cutting disc dips into water in the water bath to between 6.25% and 6.75% of the disc diameter.

5. A machine according to any of the preceding claims, wherein the cutting disc has a grit diameter of 80/100 and a width of 1 mm.

6. A machine according to any of the preceding claims, wherein the arbor is arranged for rotation at about 2500 r.p.m.

7. A machine according to claim 6, wherein the work-table is provided with a plurality of apertures in the region of the slot through which the cutting disc projects, which apertures communicate with the water bath therebeneath.

8. A machine according to claim 7, wherein a plurality of slot-like apertures are arranged generally perpendicularly to the cutting disc slot, around the periphery thereof.

9. A machine according to claim 7 or claim 8, wherein a plurality of circular holes are provided, adjacent the cutting disc slot.

10. A machine according to any of claims 1 to 6, wherein a plurality of grooves are provided in the surface of the work-table, all of which grooves lead to the cutting disc slot so as to allow the drainage of liquid from the work-table surface back into the water bath.

11. A machine according to any of the preceding claims, wherein an adjustable guide for tiles being cut is provided on the work-table, along which guide tiles may be slid whilst being cut by the diamond dust cutting disc.

12. A machine according to any of the preceding claims, wherein a metallic casing is provided to house the entire machine, the work-table forming the top surface of that casing.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. to the two bosses 36. The bar 37 may be locked in any desired position across the width of the worktable by means of screws 38 provided one in each boss 36 and serving to clamp the associated boss 36 to its rod 35. To facilitate the positioning of the guide bar 37, graduated rules 39 are affixed to the top face of the work-table, adjacent the ends of the casing, as illustrated in Figure 1. A guard assembly is provided for the cutting disc 29 which assembly comprises a part-circular housing 40 affixed to the lower end of a rod 41 which passes through a bush 42 provided on an L-shaped arm 43. A screw clamp 44 is provided in the bush 42, whereby the height of the housing 40 may be adjusted relative to the top surface of the work-table. The L-shaped arm 43 is mountd in a clamp 45, provided on a side wall 12 of the casing, adjacent one end thereof. In this embodiment of the invention, the diamond dust cutting disc 29 has nominal diameter of 153 mm and an axial width of 1 mm. The cutting disc has an apparently relatively smooth periphery and smooth peripheral margins on the side faces thereof, but the disc periphery and a 5 mm wide peripheral margin of each side face carry bonded diamond cutting dust of a grit 80/100. A suitable cutting disc is manufactured by Diagrit Diamond Tools Limited, and sold under the reference no. B 11851. The electric motor 16 is a 1/2 h.p. 1425 rpm single phase electric motor, and the motor shaft pulley 25 has a diameter of approximately 75 mm. The arbor pulley 23 has a diameter of approximately 45 mm, such that in operation, the arbor 19 and hence the cutting disc 29 rotate at approximately 2500 rpm. Though not shown in the drawings, the water bath 26 may be provided with a drainage pipe, leading to the exterior of the casing 10 and provided with a tap, to facilitate the emptying of the bath. Moreover, a water supply pipe and level pipe may also be provided, if required. In operation, the water bath 26 is filled with water to the required level and most preferably this is such that the lower 10 mm of the cutting disc 29 dips into the water contained in the water bath 26. Then, by turning on the switch of the control arrangement in housing 17, the cutting disc 29 will be rotated at the appropriate speed and tiles may be cut by being slid over the work-table surface, to be severed by the cutting disc 29. During this operation, the cutting disc picks up water contained within the water bath, this serving both to lubricate the cutting disc and to cool the disc and the tile in the region of the cut. Moreover, such dust as is created by the cutting operation forms a slurry with that water, to drain back into the water bath 26, through the grooves 32 and the holes 31 and 33. If a simple linear cut is to be made on a tile, the guide bar 37 may be set at an appropriate position and then locked in place by means of the screws 38 in the bushes 36. However, the tile cutting machine of this invention may be used without employing the guide bar 37, and indeed tests have shown that it is possible to cut a variety of complex shapes out of a tile, simply by carefully sliding the tile over the work table, to be cut appropriately by the disc 29. CLAIMS Filed on 19. 1.84

1. A machine suitable for cutting a tile (as hereinbefore defined), which machine comprises the combination of a work-table having a slot in the surface thereof, a rotatable arbor mounted beneath the work-table, and carrying a diamond dust cutting disc a portion of the periphery of which projects through the slot in the work-table, power drive means arranged to rotate the arbor and hence the cutting disc at a speed sufficient to permit the cutting of a tile thereby, and a water bath disposed beneath the cutting table and into which a lower sector of the diamond cutting disc projects for dipping into water contained in the water bath.

13. A machine suitable for cutting a tile and

substantially as hereinbefore described, with reference to and as illustrated in the accompanying drawings.