GB2073630A - Sand-blasting equipment - Google Patents

Abstract

Sand-blasting equipment capable of operating with wet common sand or wet silver sand comprises a gun (1) having a nozzle (2) at one end and a connection (3) with a shut-off valve (4) at the other for a high pressure water line (5). The nozzle (2) includes an injector for sand (6) drawn through a feed hose (7) from a hopper (9) in a container (8). The container has a compartment (10) and an inclined wall (11) between the hopper and the compartment with an aperture (12) covered by a mesh (13). A bleed hose (14) extends from between the nozzle (2) and the shut-off valve (4) and has an outlet (16) within the compartment (10) and directed towards the mesh (13). An inlet (17) for the feed hose (7) is adjacent to the bottom of the compartment (10), whereby water bled through the bleed hose (14) is directed at the mesh (13) and washes sand from the hopper (9) into the compartment (10) from whence the suspension of sand in water is induced to flow to the nozzle (2). <IMAGE>

Description

SPECIFICATION Sand-blasting equipment This invention relates to sand-blasting equipment of the type in which a gun has a nozzle at one end and a connection with a shut-off valve at the other end for a high pressure water line, and in which the nozzle includes an injector for sand induced through a feed hose from a container.

Hitherto, such equipment has been capable of operating only with appropriately prepared fine dry sand, and therefore, the object of the invention is to provide such equipment that is capable of operating with wet common sand or wet silver sand, which may be collected for re-use.

According to the present invention, a sandblasting equipment comprises a gun having a nozzle at one end-and a connection with a shut-off valve at the other end for a high pressure water line, the nozzle including an injector for sand drawn through a feed hose from a container, a hopper for sand in the container, a compartment in the container, a wall between the hopper and the compartment with an aperture covered by a mesh, a bleed hose from between the nozzle of the gun and the shut-off valve, an outlet for the bleed hose within the comDartment and directed towards the mesh covering the aperture, and an inlet for the feed hose adjacent to the bottom of the compartment.

When the hopper contains sand, e.g., common sand which may be wet, and the shut-off valve is open, high pressure water bled through the bleed hose is directed by the outlet at the mesh covering the aperture and washes sand from the hopper through the mesh into the compartment, where the sand is suspended in the water, and high pressure water passing through the injector in the nozzle induces a flow of sand and water through the feed hose from the compartment to the nozzle.

The mesh-covered aperture is preferably adjacent the lower end of an inclined wall of the hopper, so that passage of sand through the mesh is assisted by gravity, as well as feeding of sand in the hopper to the aperture. The mesh is preferably a woven wire mesh or gauze, with a mesh size suited to the grade of sand being used. The compartment preferably has a pair of inclined walls, one parallel to the inclined wall of the hopper and the other perpendicular thereto, forming a trough bottom adjacent to the bottom of which is a mouth of the inlet of the feed hose.

The hopper is preferably removable from the top of the container, so as to afford access to the mesh-covered aperture for cleaning and/or replacement of the mesh, and also to afford access to the compartment with the outlet for the bleed hose and the inlet for the feed hose. Thus, an upper edge of the container is preferably turned inwards to form a lip serving to stiffen an opening at the top of the container and to support a flange round the open top of the hopper. The inclined walls of the compartment are preferably provided by a member mounted in the container, and the member has side walls and inclined edges to mate with the inclined wall of the hopper alongside the mesh-covered aperture.

The gun preferably has its shut-off valve 'incorporated in a handgrip having a trigger for opening the shut-off valve against the pressure in the high pressure water line, and the feed hose from the container is connected to the nozzle by a pipe having a portion extending parallel to the barrel of the gun, and a tie-plate is secured to both the pipe and the barrel to form a second handgrip.

The bleed hose is preferably provided with an adjustable throttle valve adjacent the gun, to enable the amount of bleed water to be adjusted in accordance with the amount of sand required to be washed down and drawn through the feed hose to the nozzle.

The basis of the invention and preferred embodiments of container and gun will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a diagrammatic perspective view illustrating the basis of the invention; Figure 2 is a perspective view of a preferred form of portable container for use in the invention; Figure 3 is a perspective view of the removable hopper of the container of Figure 2; Figure 4 is a view of the container of Figure 2 from above with the hopper removed; and Figure 5 is an elevation of a preferred form of gun for use in the invention.

The sand-blasting equipment shown in Figure 1 comprises a gun 1 having a nozzle 2 at one end and a connection 3 with a shut-off valve 4 at the other end for a high-pressure water line 5, the nozzle including an injector (not visible) for sand 6 drawn through a feed hose 7 from a container 8, a hopper 9 for the sand in the container, a compartment 10 in the container, an inclined wall 11 between the hopper and the compartment with an aperture 12 covered by a wire gauze 13 adjacent the lower end, a bleed hose 14 from between the nozzle 2 of the gun 1 and the shut-off valve, with an adjustable throttle valve 1 5 adjacent the gun, an outlet 16 for the bleed hose 14 within the compartment 10 and directed towards the mesh 1 3 covering the aperture 12, and an inlet 1 7 for the feed hose 7 with a mouth 1 8 adjacent to the bottom 1 9 of a trough at the bottom of the compartment formed by a pair of inclined walls 20, 21, one parallel to the inclined wall 11 of the hopper 9 and the other perpendicular thereto.

When the shut-off valve 4 is open, high pressure water bled through the bleed hose 1 4 is directed by the outlet 1 6 at the gauze 13 covering the aperture 12 and washes sand 6 from the hopper 9 through the gauze into the compartment 10, where the sand is suspended in the water, in amount determined by adjustment of the throttle valve 15, and high pressure water passing through the injector in the nozzle 2 induces a flow of sand and water through the feed hose 7 from the mouth 18 of the inlet 17 in the compartment 10 to the nozzle 2.

In Figures 2 to 4 the container 8 is mounted on a pair of wheels 22 (only one being visible in Figure 2) and has a handlebar 23 for propelling it a leg 24 being provided to support the container upright when not being moved. The upper edge25 of the container is turned inwards to form a lip serving to stiffen the opening at the top of the container and to locate and support a removable hopper 9 having a flange 26 round its open top.

The container 8 and hopper 9 are conveniently GRP mouldings, as is also a member 27 providing the inclined walls 20,21 of the compartment 10, and side walls 28 of the member 27 have inclined edges 29 to mate with the inclined wall 1-1 of the hopper 9 alongside the aperture 12 covered with gauze 1 3. A plate 30 secured to the inclined wall 20 of the member 27 carries the outlet 1 6 and the inlet 17, which are connected, by pipes not visible below a mounting bracket 31 for the member 27, to unions 32, 33 respectively for hoses 14, 7 respectively to and from the gun 1. The gauze 13 slides into three rebated frame members 34 and is readily removable by means of a handgrip 35 for cleaning or replacement.

The gun 1 shown in Figure 5 has its shut-off valve 4 incorporated in a handgrip 36 having a trigger 37 for opening the shut-off valve against the pressure of water from the supply hose 5. The hose 7 is connected to the nozzle 2 by a pipe 38 having a portion extending parallel to the barrel 39 of the gun, and a tie-plate 40 is welded to both the pipe 38 and the barrel 39 to form a second handgrip.

Claims (10)

1. Sand-blasting equipment comprising a gun having a nozzle at one end and a connection with a shut-off valve at the other end for a high pressure water line, the nozzle including an injector for sand drawn through a feed hose from a container, a hopper for sand in the container, a compartment in the container, a wall between the hopper and the compartment with an aperture covered by a mesh, a bleed hose from between the nozzle of the gun and the shut-off valve, an outlet for the bleed hose within the compartment and directed towards the mesh covering the aperture, and an- inlet for the feed hose adjacent to the bottom of the compartment.

2. Equipment as in Claim 1, wherein the meshcovered aperture is adjacent the lower end of an inclined wall of the hopper.

3. Equipment as in Claim 2, wherein the compartment has a pair of inclined walls, one parallel to the inclined wall of the hopper and the other perpendicular thereto, forming a trough bottom adjacent to the bottom of which is a mouth of the inlet of the feed hose.

4. Equipment as in any one of the preceding Claims, wherein the hopper is removable from the top of the container.

5. Equipment as in Claim 4, wherein an upper edge of the container is turned inwards to form a lip serving to stiffen an opening at the top of the container and to support a flange round the open top of the hopper.

6. Equipment as in Claim 4 or Claim 5 in combination with Claim 3, wherein the inclined walls of the compartment are provided by a member mounted in the container, and the member has side walls with inclined edges to mate with the inclined wall of the hopper alongside the mesh-covered aperture.

7. Equipment as in any one of the preceding Claims, wherein the gun has its shut-off valve incorporated in a handgrip having a tripper for opening the shut-off valve against the pressure in the high pressure water line, and the feed hose from the container is connected to the nozzle by a pipe having a portion extending parallel to the barrel of the gun, and a tie-plate is secured to both the pipe and the barrel to form a second handgrip.

8. Equipment as in any one of the preceding Claims, wherein the gun bleed hose is provided with an adjustable throttle valve adjacent the gun.

9. Sand-blasting equipment substantially as hereinbefore described with reference to Figure 1 of the accompanying drawings.

10. Sand-blasting equipment substantially as hereinbefore described with reference to Figures 2 to 5 of the accompanying drawings.