GB2496147A

GB2496147A - Apparatus and method for an abrasive cleaning tool

Info

Publication number: GB2496147A
Application number: GB201118888A
Authority: GB
Inventors: Christopher Baglin
Original assignee: Individual
Current assignee: Individual
Priority date: 2011-11-02
Filing date: 2011-11-02
Publication date: 2013-05-08
Also published as: GB201118888D0

Abstract

The apparatus is a grit-blasting tool for abrasive cleaning and has a housing (8, figure 1), an inlet (14, figure 3) and an outlet (16, figure 3), a powered device which may be an angle grinder (4a, figure 1) or the like connected to the housing to cause a fluid to flow and a means for introducing particulate matter into said fluid flow. The housing is made of two opposed side walls with a space between for the impeller device 4b, the housing may be made of a metallic material which may be lined with a plastics material such as polyurethane. The powered device drives a gear head 12 and a plurality of vanes 10 are rotated by the gear head. Connected to inlet (14, figure 3) is a conduit 18 which extends to a source of abrasive material. A conical nut 22 holds the impeller device 4b in place and aids in distribution of abrasive matter when inlet (14, figure 3) is opposite nut 22, alternately a gravity feed hopper 24 may be used fitted by device 28. Outlet 18 decreases with width, the very end tips (30, figure 3) of which are lengthways adjustable.

Description

APPARATUS AND METHOD

This invention relates to an abrasive cleaning tool and in particular to an airless, portable and relatively compact abrasive cleaning tool.

Conventionally, abrasive cleaning tools, such as grit-blasting tools require a source of compressed air to drive the grit element onto a work piece. Having a source of compressed air has its associated problems of transporting from job-to-job the source, which can be relatively large to the size of the tool, In addition the overafi apparatus needed can be quite cumbersome, especially for smaller jobs.

According to one aspect of the present invention, there is provided apparatus comprising a housing, an inlet and an ouUet to said housing, a powered device connected to said housing to cause a fluid flow from the inlet to the outlet and means for introducing particulate matter into said fluid flow, the arrangement being such that said powered device serves to reduce pressure inside said housing in the region of the inlet.

According to a second aspect of the present invention, there is provided a method comprising inducing a low pressure at an inlet of a housing causing a fluid flow from the inlet to an outlet of a housing and introducing particulate matter into said fluid flow.

Owing to these aspects, a portable and relatively compact abrasive cleaning tool can be provided which operates on the basis of suction of the particulate matter into the housing.

In order to clearly and completely disclose the present invention, reference will now be made, by way of example only, to the accompanying drawings, in which:-Figure 1 shows a diagrammatic view of a tool arrangement, Figure 2 is a partial section of the tool of Figure I, and

II-

Figure 3 is a view similar to Figure 2, but from an orthogonal position.

Referring to the Figures, an abrasive tool arrangement 2 comprises a hand-held tool 4, which is preferably electrically operated by way of an electrical cord 6. The tool 4 is advantageously based on a tool part, such as a powered device in the form of an angle grinder part 4a, or the like, to which is connected an impeller device part 4b which comprises a housing 8 and a plurality of rotatable vanes 10. The housing B comprises two opposed side wall portions 8a and Sb connected together around peripheral regions thereof, with for example bolts, with one or both wall portions Ba and 8b being shaped so as to leave a space therebetween for the impeller device part 4b. The housing can be of any material of suitable strength, but is preferably made of a metallic material, such as steel. Advantageously, if the housing 8 is made from metallic material, then the material is lined on its inner part or parts with a plastics material, such as polyurethane. The polyurethane forms a seal between the is metallic parts and as such fills any gaps that would be present if the metallic parts were to abut each other directly and thus prevents leakage.

The electrical motor in the angle grinder tool part 4a drives a geared head 12 arranged at a right-angle to the main axis 13 of the tool body. Conventionally, an abrasive disc or a thinner cut-off disc is mounted to the geared head of the angle grinder, either of which can be replaced when worn. In the present case, however, that disc is removed and the impeller device part 4b is connected to the geared head 12 instead, and the plurality of vanes 10 are drivingly rotated by the geared head in the direction of the arrows Ii (shown in Figure 3).

The housing 8 of the impeller device part 4b has an inlet 14 and an outlet 16.

Connected to the inlet 14 is a conduit 18, or the like, which is, preferably, flexible and which extends to a source of abrasive particulate matter 20, for example in the form of a sack, bag or other suitable container of the material. By way of the rotation of the vanes 10 at a high speed, for example, substantially 6000 revolutions per minute, a reduction in the pressure at the inlet 14 and in the conduit 18 is created compared to atmospheric pressure and which is sufficient enough to cause a suction action of the abrasive matter up the conduit 18, through the inlet 14 and into the interior of the housing 8. It is preferable that a large differential in pressure is created between the inlet 14 and atmospheric pressure in order to cause the maximum degree of suction.

A conical nut 22 holds the impeller device part 4b in place within the housing 8. In the case where the inlet 14 is opposite the nut 22, the arrangement aids in the even distribution of the particulate abrasive matter around the impeller part 4b and between the vanes 10. In an alternative arrangement, the abrasive matter is contained in a gravity feed hopper 24 connected to an upper end of the housing 8 by way of a valve 26, such as a butterfly valve. For this purpose a hopper fitting device 28 is provided on the housing 8. Clearly, the matter only enters the housing 8 via the inlet 14 or by way of the hopper fitting 28 which would form the inlet in the case of use of the gravity feed hopper 24. The use of a gravity feed hopper 24 is preferable when the abrasive matter is of a relatively large particulate, such as heavy grits in the form of chilled iron or glass bead type medias.

The high speed of rotation of the vanes 1 0 propels, by centrifugal force, the abrasive matter towards the outlet 16, which gradually decreases in width in order to intensify the blast of the matter being forced out of the outlet 16. Advantageously, the very end tips 30 are lengthways adjustable to further intensify the outward blast.

The vanes 10 are, advantageously, of a specific form, with a base portion ba which extends substantially perpendicularly from a base wall 4c of the impeller 4b to which it is connected and substantially parallely to the axis of rotation 15 of the vanes 10, and an upper portion lob which extends obliquely to one side of the base portion 1 Oa. This form of the vanes 10 serves a dual function, the first being that the upper portion lOb is so obliquely angled to produce a sufficient enough reduction in pressure at the inlet 14 to be able to produce a suction of a mix of air and the abrasive matter along the conduit 18; and the second being that the base portion ba is arranged to propel the abrasive matter out of the outlet 16 at high velocity.

There are, in Figure 2, four equi-angularly spaced vanes 10 shown, although the number or size of vanes 10 can be varied, for example according to the type and/or size of abrasive matter to be used. Thus the base wall 4c and its connected vanes can be removed by removing the conical nut 22 and replaced with another base wall and vane unit with a different number of vanes connected thereto.

Conventional angle grinders typically have an adjustable detachable guard 32 which S surrounds the rotating parts. The guard 32 is detached simply by releasing an over-centre catch whereby the impeller device part 4b connects to the angle grinder tool part 4a. A standard 9 inch workshop angle grinder has ample power to drive the tool arrangement 2.

The propelled abrasive matter is directed at a workpiece 34, such as metal railings, metal gates, car body parts and other small, corroded metallic items. The tool arrangement 2 is also suitable for cleaning concrete or brickwork and detailed cleaning of intricate stonework and carvings.

Claims

<claim-text>CLAIMS1. Apparatus comprising a housing, an inlet and an outlet to said housing, a powered device connected to said housing to cause a fluid flow from the inlet to the outlet and means for introducing particulate matter into said fluid flow, the arrangement being such that said powered device serves to reduce pressure inside said housing in the region of the inlet.</claim-text> <claim-text>2. A method comprising inducing a ow pressure at an inlet of a housing causing a fluid flow from the inlet to an outlet of a housing and introducing particulate matter into said fluid flow.Samendments to the claims have been filed as follows 1. Apparatus comprising a housing, an inlet and an outlet to said housing, a powered device connected to said housing to cause a fluid flow from the inlet to the outlet and means for introducing particulate matter into said flow, the arrangement being such that said powered device serves to reduce pressure inside said housing at the inlet such that the particulate matter is expelled through the outlet.
2. Apparatus according to claim 1, wherein said housing comprises an impeller device.</claim-text> <claim-text>3. Apparatus according to claim 2, wherein said impeller device includes a plurality of vanes.</claim-text> <claim-text>4. Apparatus according to claim 2 or 3, and further comprising a geared head between the powered device and the housing and to which the impeller device is connected.</claim-text> <claim-text>5. Apparatus according to any preceding claim, wherein the powered device is an angle grinder tool. r</claim-text> <claim-text>6 Apparatus according to any preceding claim, and further comprising a conduit connected to the inlet at one end and to a source of the particulate material at another end.</claim-text> <claim-text>7. Apparatus according to claim 6, wherein the particulate material is an abrasive material.</claim-text> <claim-text>8. Apparatus according to any one of claims 2 to 7, wherein the impeller device is connected to the housing by way of a conical nut having its conical head projecting centrally into the housing.</claim-text> <claim-text>9. Apparatus according to claim 8, wherein the inlet is located opposite the conical nut.</claim-text> <claim-text>10. Apparatus according to any preceding claim, wherein the inlet is at an upper end of the housing.</claim-text> <claim-text>11. Apparatus according to any one of claims 3 to 10, wherein each of the plurality of vanes includes a base portion extending substantially perpendicularly from a base wall of the impeller device adjacent a side wall portion of the housing to which it is connected and substantially parallel to an axis of rotation of the vanes, and an upper portion which extends obliquely inwardly towards the axis of rotation.</claim-text> <claim-text>12. Apparatus according to any one of claims 2 to 11, wherein the impeller device is a unit which is removable from the housing and replaceable with another impeller device.</claim-text> <claim-text>13. Apparatus according to any preceding claim, wherein the outlet gradually decreases in width.</claim-text> <claim-text>14. Apparatus according to claim 13, wherein the outer end of the outlet is lengthways adjustable to further narrow the outlet.</claim-text> <claim-text>15. A method comprising inducing a low pressure at an inlet of a housing causing a fluid flow from the inlet to an outlet of a housing, introducing particulate matter into said flow and expelling the particulate matter through the outlet.</claim-text> <claim-text>16. A method according to claim 15, wherein the inducing a low pressure at the inlet is by way of rotation of an impeller device within the housing.</claim-text> <claim-text>17. A method according to claim 16, wherein the rotation causes the introducing of the particulate material into the housing.</claim-text> <claim-text>18. A method according to any one of claims 15 to 17, and arranging the inlet to be located opposite to a conical nut connecting the impeller device, so as to evenly distribute the particulate material within the housing.</claim-text> <claim-text>19. A method according to any one of claims 15 to 17, and mounting a gravity hopper to the inlet located at an upper end of the housing.</claim-text> <claim-text>20. A method according to any one of claims 16 to 19, and further comprising removing the impeller device and replacing the impeller device with another impeller device.</claim-text> <claim-text>21. Apparatus as substantially hereinbefore described with reference to the accompanying drawings.</claim-text> <claim-text>22. A method as substantially hereinbefore described with reference to the accompanying drawings.</claim-text>