Dust collection system and device

Abstract

A device and system for removing dust during drilling operations. The system comprising: a device configured to be placed on a drilling surface; an air permeable dust collection receptacle (500); and a compressed air supply for supplying a compressed air flow into the device. The device comprising: a housing; an air inlet (232), connected to the compressed air supply; and a main outlet (238) connected to the dust collection receptacle (500). The housing comprising: an enclosure (240) for a drilling site at the drilling surface, the enclosure (240) comprising an aperture configured to allow a drill bit to pass into the enclosure (240) to reach the drilling site; and a first flow path for the compressed air flow from the compressed air supply, through the air inlet (232) to the main outlet (238). The enclosure (240) further comprises a dust outlet (248) connected to the first flow path. The housing is configured to constrict the first flow path upstream of the dust outlet and then dilate it at and / or downstream of the dust outlet (248). In use, the compressed air flow following the first flow path causes a reduction in pressure at the dust outlet (248) and in the enclosure (240), so that dust is drawn from the drilling site through the dust outlet (248) and carried by the compressed air flow to the main outlet (238) to be collected by the dust collection receptacle (500).

Description

[0001] DUST COLLECTION SYSTEM AND DEVICE

[0002] This disclosure relates to a system and device which can be used to collect dust created from drilling.

[0003] Drilling activities are known to create dust and debris when creating a drilled hole. This dust and debris can spread and make considerable mess. Dust particles also easily spread in the air and can then be inhaled in by a drilling operator. This is particularly problematic with drills designed to be operated by a single person, ranging from drills used in domestic settings, to those used on building sites and roads like pneumatic drills. When performing drilling operations with pneumatic drills, air flows through the drill bit exiting at the tip to remove dust and debris from the hole to prevent the drill jamming, which can further spread any dust produced.

[0004] Pneumatic rock drills are commonly used when drilling through hard surfaces like tarmac and concrete. The dust created from such drilling operations can include large volumes of silica dust and other carcinogens which can cause health problems when inhaled, and cause damage to the local environment. Pneumatic drills have a supply of compressed air which escapes the drill bit towards its tip, and dust created in drilling operations is carried by the escape of the compressed air to wide distances, spreading these dangerous dust particles into the air. However, rock-drilling using pneumatic drills is an essential part of road maintenance, and also regularly used in bar hole drilling when looking for leaks in sub-surface gas pipes.

[0005] According to a first aspect of the present invention there is provided a system for removing dust during drilling operations, the system comprising: a device configured to be placed on a drilling surface; an air permeable dust collection receptacle; and a compressed air supply for supplying a compressed air flow into the device; wherein the device comprises: a housing; an air inlet, connected to the compressed air supply; and a main outlet connected to the dust collection receptacle; wherein the housing comprises: an enclosure for a drilling site at the drilling surface, the enclosure comprising an aperture configured to allow a drill bit to pass into the enclosure to reach the drilling site; and a first flow path for the compressed air flow from the compressed air supply, through the air inlet to the main outlet; wherein the enclosure further comprises a dust outlet allowing dust created at the drilling site to exit the enclosure, wherein the dust outlet is connected to the first flow path; wherein the housing is configured to constrict the first flow path upstream of the dust outlet and then dilate the first flow path at and / or downstream of the dust outlet, and wherein, in use, the compressed air flow following the first flow path causes a reduction in pressure at the dust outlet and in the enclosure, so that dust is drawn from the drilling site through the dust outlet and carried by the compressed air flow to the main outlet to be collected by the dust collection receptacle.

[0006] It will be appreciated that the shaping of the first flow path by the housing allows Bernoulli’s principle to be utilized, resulting in the reduction in pressure in the enclosure by its connection to the first flow path, due to the position of the dust outlet in the first flow path. By constricting the compressed air flow in the device, the compressed air will have increased velocity and reduced pressure, and as the flow path then dilates, the compressed air reduces in velocity and increases in pressure, in accordance with Bernoulli’s principle. This effectively creates a suction effect at the dust outlet, pulling dust created by the drilling operation into the dust collection receptacle rather than letting it dissipate in the environment. This prevents any users from inhaling any dust particles, and helps restrict said particles being released into the local environment causing problems to local populations. As dust particles from activities like bar hole drilling can contain carcinogens, collection of the dust by the dust collection receptacle is important for the health and safety of any user and any other people located close to drilling operations. The system provides an easy to use, and easily portable device which can effectively reduce and may prevent dust spread from drilling operations.

[0007] It will be appreciated that the air permeable dust collection receptacle can be any receptacle which collects dust particles, whilst allowing air to escape. The whole of the dust collection receptacle may be air permeable, or a portion of the receptacle may be air permeable. The receptacle may be a replaceable, or a reusable. The receptacle may be a dust filter attached to the main outlet. The dust collection receptacle may be bag or another type of container. The receptacle may be sealable after removal from the main outlet to allow for safe disposal of contaminated materials.

[0008] In some examples the housing may further comprise an air amplifier configured to perform the constriction and dilation of the first flow path and to provide the connection between the dust outlet and the first flow path, the air amplifier comprising: a cylindrical chamber having a circumferential wall extending between a first axial end and a second axial end along a main axis; and an annular channel positioned around the circumferential wall, wherein the air inlet is connected to the annular channel, the annular channel configured to direct the first flow path into the cylindrical chamber through a gap in the circumferential wall in a direction towards the second axial end; wherein the annular channel is angled relative to the main axis at an angle greater than 0° and less than 90°; wherein the dust outlet is connected to the first axial end of the cylindrical chamber, and the main outlet is connected to the second axial end of the cylindrical chamber; wherein the air amplifier is configured to restrict the first flow path through the annular channel, and to dilate the first flow path after the compressed air flow has entered the cylindrical chamber through the gap; wherein, in use, the compressed air flow following the first flow path through the annular channel experiences the Coanda effect when injected into the cylindrical chamber through the gap, such that the compressed air flow follows the circumferential wall of the cylindrical chamber and entrains the dust drawn through the dust outlet along the main axis towards the second axial end.

[0009] It will be appreciated that by having the first flow path enter the cylindrical chamber an angle greater than 0° and less than 90° the air amplifier is able to utilise the Coanda effect, where a jet of fluid emerging an orifice (i.e. entering the cylindrical chamber) follows an adjacent flat or curved surface, to direct the air flow towards the main outlet whilst encouraging the compressed air flow to adhere to the inside surface of the cylindrical chamber. This causes the surrounding ambient air to be entrained with the high-velocity air stream pulling in dust from the dust outlet. In some examples the gap is around a portion of the circumference of the circumferential wall, however in other examples the gap may be around a substantial portion of the circumferential wall, or the gap may be around the whole of the circumference of the wall. It will be appreciated that if the first flow path can be directed around more of the inside surface of the cylindrical chamber more of the surrounding air (and therefore dust) can be entrained with the flow, creating a more efficient removal of dust form the drilling site. In use, the air amplifier may create a flow rate of dust through the dust outlet at least twice that of a flow rate of the compressed air supply, and increase the flow rate of the compressed air by at least three times that of the flow rate of compressed air supply. In some examples the angle is less than 75°, in some examples 45°, in some examples less than 45°, in some examples between 10° and 30°. In some examples the annular channel is funnel shaped so that it is narrowest at the gap. In some examples the velocity of the dust through the air amplifier is at least 10m / s.

[0010] In some examples, the constriction of the first flow path is performed in a portion of the housing (e.g. in the air amplifier), allowing for a better control of the change in flow rate (and therefore velocity of the compressed air), and resulting pressure changes which cause the suction effect at the dust outlet and in the enclosure. In other examples, the change in the first flow path begins at the air inlet, where the constriction of the flow path is relative to the flow path in a pipe of the compressed air supply. In some examples the compressed air supply is connected to the air inlet via a pipe. The compressed air supply may be provided at a distance from the device (e.g. in a van).

[0011] In some examples, the drilling operation is performed using a pneumatic drill. The pneumatic may be supplied by the same compressed air supply as is provided in the system, and is for connection to the device. The compressed air from the pneumatic drill may escape the drill bit in the drilling site, and be directed through the dust outlet and out of the main outlet by the reduction in pressure at the dust outlet and in the enclosure around the drilling site, caused by the shape of the housing. The device is therefore particularly advantageous when used with pneumatic drills as it prevents wide spread of dust particles which would otherwise be carried by the compressed air in the drill bit. It will also be appreciated, that by using the same compressed air supply as the pneumatic drill, the system and device can be easily used with known drilling mechanisms and equipment. The device can also maximise usability by drill users and is designed promote safe posture for drilling operators when placed facing away from the drill operator on the ground. In some examples the drilling operation may be performed by a drill directly operated by a user (e.g. by standing over the drill site), however in other examples the drill may not require direct user operation (e.g. the drill may be automated so the user does not stand directly over the drilling site). It will be appreciated that even if a user is not directly standing over a drill site, it is still advantageous to the local environment to use the device to collect dust from the drilling operation.

[0012] In some examples the enclosure may further comprise a first seal around the aperture, the first seal configured to allow a drill bit to pass through the aperture and restrict movement of dust out through the aperture. The aperture being in a top surface of the enclosure and device, on the opposite side to the drilling surface, could allow dust created at the drill site to escape through the aperture instead for being drawn through the housing. By adding the first seal around the aperture, a seal is created against the drill bit, and dust is prevented from escaping. In pneumatic drilling operations, as the drill bit is inserted deeper into the drilling surface the air escaping the drill bit comes out substantially parallel with the drill bit, instead of perpendicular to the drill bit when it is at the drilling surface. The addition of this first seal is therefore particularly advantageous when using pneumatic drills, as it prevents escape of dust with the compressed air from the drill bit and allows it to be instead caught by the suction of the dust outlet. It will be appreciated that the seal could be of different forms, which allow the drill bit to move through the aperture whilst retaining a seal. However, in some embodiments the first seal is a brush seal. The brush seal easily compensates for the varying radius of the drill bit as it passes into the drilling surface, ensuring a good seal is maintained for all drill rotations. In addition, the first seal (e.g. the brush seal) may (be such as to) allow air from outside the device to be pulled into the enclosure, further helping to ensure that dust particles are entrained with the air flow through the dust outlet. In some examples, the enclosure may further comprise a second seal configured to create a seal around the drilling site, the second seal acting between the enclosure and the drilling surface. The second seal helps to ensure the dust is caught in the enclosure, and does not escape underneath the device. In some examples the enclosure comprises a second aperture in line with the first aperture (i.e. the aperture described above), and configured to sit on the drilling surface and be located over the drilling site. However, in some other examples, the enclosure is open on the lower surface (i.e. to sit over the drilling surface), and enclosed over the top surface of the device. In embodiments where a first seal is a brush seal and a second seal is also used, the combination helps to ensure that air enters the enclosure through the first seal i.e. parallel with the drill bit during operation, helping ensure no dust escapes the enclosure, and it is instead entrained with the airflow through the device.

[0013] In some examples, the housing may further comprise one or more surface contact portions on a wall of the housing facing the drilling surface i.e. the side which touches the drilling surface, or the bottom surface. The surface contact portions may be configured to contact the drilling surface (i.e. in use) so as to tilt the housing towards the enclosure. The surface contact portions can help ensure the enclosure sits against the drilling surface around the drilling site, and can help increase any seal between the drilling surface and the enclosure. The effect of the surface contact portions is best when the device is placed on a predominantly horizontal surface, or the drilling site around the location of the enclosure is predominantly flat. When placed on a predominantly horizontal surface (e.g. the ground) the surface contact portions may help to direct the weight of the device through onto drilling site, and in some examples the second seal, so as to better seal the enclosure with the drilling surface. Thus, in some examples the device is configured such that the weight of the device against the drilling surface is sufficient to cause the enclosure to seal against the drilling site. In some examples there may be two surface contact portions. In other examples there may be three of more surface contact portions. In some examples the surface contact portions may be integrated with the housing, however in other embodiments they may be additional to the housing. The surface contact portions may be fixed, or may be adjustable to compensate for uneven drilling surfaces. In some examples the aperture may be located substantially centrally in the enclosure. In some examples, the enclosure may be substantially circular around the aperture, and the dust outlet may be configured to direct dust substantially radially out of the enclosure. By circular around the aperture, the side walls between the top wall and the bottom of the enclosure for placing on the drilling surface may be circular around the aperture. The top wall (i.e. opposite wall to that designed to be placed on the drilling surface) may be flat, or may be curved or angled from the side walls. In other examples, the enclosure may have a spiral shape with increasing radius centred around the aperture, and the dust outlet may be configured to direct dust circumferentially out of the enclosure at the widest radius of the spiral. It will be appreciated that the spiral shape is similar to that of a conch around the aperture. Such a shape may take advantage of the Coanda effect, where the dust being pulled out of the enclosure sticks to the curved surface of the enclosure after being pulled radially out of the drilling site. This design optimises the air fluid flow through the enclosure, to maximise the amount of dust caught, and minimise the pressure difference required by the shaping of the housing to create sufficient suction effect in the enclosure.

[0014] In some examples, the enclosure may further comprise a plurality of protrusions provided around the aperture extending between a bottom of the enclosure and a top of the enclosure. It will be appreciated that the top of the enclosure will be the wall opposite to the side of the device which contacts the drilling surface, and the aperture may be provided in the top of the enclosure. The top of the enclosure may provide support for the protrusions around the aperture. The bottom of the enclosure may be open to the drilling surface, or may be a walled section with an aperture for the drill bit to pass through to the drilling surface. The protrusions may be configured to encourage circular flow and allow the dust to pass through to the dust outlet and the dust collection receptacle. The resulting circular flow can help prevent dust escape, particularly in the example of using a pneumatic drill as a result of the high pressure air coming from the drill bit. It will be appreciated that the plurality of protrusions will be separated by gaps through which air and dust from the drilling site flow into the rest of the enclosure. The gaps may be configured to take advantage of the venturi effect further increasing air flow from the drilling site through the device. In some examples each gap between the plurality of protrusions is the same, however in some examples the gaps may be of varying length. The varying of the gaps between the plurality of protrusions may also create areas of air turbulence which can further help with encouraging circular flow in the enclosure. Furthermore, the presence of relatively large and relatively small gaps between the protrusions allows both fine dust and larger particles to be transported to the filter bag and prevents blocking. Thus, in some examples the gaps may comprise at least a first gap of a first length and a second gap of a second length, wherein the first length is larger than the second length. The first length may be more than 50% larger than the second length, optionally more than double, optionally more than quadruple. There may be (at least) two gaps of the first length and at least two gaps of the second length. Optionally there may be six protrusions, separated by two gaps of the first length and four gaps of the second length.

[0015] In some examples, the housing may comprise at least one metallic component, and the housing may further comprise an electrical grounding point. The grounding point may be configured to be connected to an external grounding point, so that any charge build up in the metal components can be discharged safely, i.e. to prevent static build-up in the device. Static charge may be created in the enclosure and housing due to the fast movement of air and dust particles through the device. In drilling operations where natural gas or other flammable materials may be present (for example bore-hole drilling to detect gas leaks), any charge if left, could spark and ignite the gas. It is therefore of increased safety to provide a manner in which electrostatic charge build up can be safely dissipated away from the device.

[0016] In some examples, the air inlet comprises a switchable valve for selectively opening the air inlet to allow compressed air into the housing. By adding a switch onto the housing, a user can connect the system and prepare without running the compressed gas flow, preventing compressed air being wasted when drilling operations are not yet started. It therefore makes the device more user friendly.

[0017] In some examples, the device may further comprise a protective cover, configured to enclose the air inlet, the main outlet and the dust collection receptacle within the housing. The protective cover therefore can ensure the vulnerable parts of the device are contained and protected. The protective cover may be selectively operable to access the air inlet and / or main outlet and / or dust collection receptacle. In some examples the housing may be shaped to allow for a pipe supplying the compressed air to be removed, and also protected when connected to the air inlet.

[0018] According to a second aspect of the present invention, there is provided a device configured to be placed on a drilling surface; the device comprising: a housing; an air inlet for connection to a compressed air supply which supplies compressed air into the housing; and a main outlet for connection to an air permeable dust collection receptacle; the housing comprising: an enclosure for a drilling site at the drilling surface, the enclosure comprising an aperture configured to allow a drill bit to pass into the enclosure to reach the drilling site; and a first flow path for the compressed air flow from the compressed air supply, through the air inlet to the main outlet; wherein the enclosure further comprises a dust outlet allowing dust created at the drilling site to exit the enclosure, wherein the dust outlet is connected to the first flow path; and wherein the housing is configured to constrict the first flow path upstream of the dust outlet and then dilate the first flow path at and / or downstream of the dust outlet.

[0019] It will be appreciated that, in use, the compressed air flow following the first flow path causes a reduction in pressure at the dust outlet and in the enclosure, so that dust is drawn from the drilling site through the dust outlet and carried by the compressed air flow to the main outlet to be collected by the dust collection receptacle.

[0020] As will be apparent to the skilled person, features of the device described with reference to the system of the first aspect, may be equally applicable to the device of the second aspect.

[0021] Certain preferred non-limiting examples of this disclosure will now be described, by way of example only, with reference to the accompanying drawings, in which: FIG. 1 is a representation of a user performing drilling operations with an embodiment of the system and device of the present invention;

[0022] FIG. 2 is a perspective view of an embodiment of the device;

[0023] FIG. 3 is a top down schematic of the inside of the device shown in FIG. 2;

[0024] FIG. 4 is a side perspective of the device shown in FIGs 2 and 3;

[0025] FIG. 5A, 5B, 6A and 6B show bottom up perspectives of embodiments of enclosures according the embodiments of the present invention;

[0026] FIG. 7 shows an example air amplifier according to an embodiment.

[0027] It will be understood that the discussion below is exemplary only. Further, although the examples described below are discussed in relation pneumatic drilling operations, it will be understood that the system and device of the present invention may be used with many other types of drilling operation.

[0028] It will be understood that references made herein to the terms “front”, “back”, “below”, “above”, “top”, “bottom”, “higher”, “lower” etc. are intended to be relative terms referring to normal orientations within the system (the orientation shown in the Figures).

[0029] FIG. 1 shows a user 10 using a pneumatic drill 20. The drill 20 has drill bit 24 and uses compressed air from a supply 22. A user 10 is using a system 100 to remove dust from the drilling operation. The system includes a device 200 with housing 230 placed on a drilling surface and connected to a compressed air supply pipe 120. The drill bit 24 passes through an aperture 242 in the device 200 and into a drilling site on the drilling surface. Dust created by the drilling operation is collected in the device 200 as described in more detail below with reference to FIGs. 2-7.

[0030] FIG. 2 shows a perspective view of the device 200 of FIG. 1. The housing has a base plate 210 (i.e. a bottom wall) to which a removable portion 220, two fixed portions231a, 231b and an enclosure (i.e. a dust capture enclosure) 240 are fixed.. An aperture 242 is provided in the dust capture enclosure 240 and is configured to allow a drill bit to pass into the dust capture enclosure 240 to reach the drilling site (shown by the arrow). The dust capture enclosure 240 has a brush seal 244 around the aperture 242. The device 200 has a switch 250 that allows the user to turn on the device when needed (e.g. as a switchable valve), a grounding point 280 to allow the device 200 to be connected to ground, a handle 260, and reflective blocks 270 that enable visibility of the device 200 in the dark.

[0031] FIG. 3 shows the internal components and the airflow within the device of FIGs.1 & 2 (i.e. parts of the housing), with a light-coloured arrow representing the flow of the compressed air supply (i.e. a first flow path), and a dark-coloured arrow representing the flow of dust and air from the drilling site within the enclosure 240. The dust capture enclosure 240 is shown with a dust outlet 248. The compressed air supply 120 is connected to the housing via a claw coupling at an air inlet 232 to an internal pneumatic hose 234. The claw coupling of the air inlet 232 is directly connected to the switch 250. When the switch 250 is turned off by a user, no compressed air can enter the device 200. When the user turns on the switch 250, the air flows through the air inlet 232 and the pneumatic hose 234 into an air amplifier 290 (described below with reference to FIG. 7). In this configuration the air amplifier 234 directs airflow from the dust outlet 248 towards a main outlet 238 and dust collection receptacle 500. This high velocity air flow away from the dust capture enclosure 240 creating a vacuum. The dust generated by the drilling operation is drawn from the enclosure 240 through the air amplifier 290 and finally collected in the receptacle 500. The first flow path therefore directs the compressed air flow from the compressed air supply 120, through the air inlet 232 to the main outlet 238, causing a reduction in pressure at the dust outlet 248 and in the enclosure 240, so that dust is drawn from the drilling site through the dust outlet 248 and carried by the compressed air flow to the main outlet 238 to be collected by the dust collection receptacle 500.

[0032] FIG. 4 shows the side perspective of the device 200 on a drilling surface 300. A ground seal 248 ensures a good seal between the drilling surface 300 and the enclosure 240 is created despite any uneven surface of the drilling surface 300. Ground contact pads 212 (i.e. surface contact portions) attached to the base plate 210 elevate the device 200 from the back end. The weight of the device 200 and the ground contact pads 212 ensure that the ground seal 248 is always touching the drilling surface 300 and a good seal is maintained. The seal created ensures a better vacuum within the enclosure 240. FIGs. 5A, 5B, 6A and 6B show example enclosures which can be used with the device described with reference to FIGs. 1-3.

[0033] FIG. 5A is a bottom up view of an embodiment of the enclosure 240 with a spiral or conch shape. The brush seal 244 ensures minimal dust escape whilst creating the aperture 242 where the drill bit can be placed, and dust collected is pulled through the dust outlet 248 as discussed above. FIG. 5B shows another embodiment of an enclosure 240’. The air is drawn into the enclosure 240 through gaps in protrusions 242. The shape of the enclosure 240’ and the protrusions 242 encourage a spiral airflow that leads the air with the dust towards the dust outlet 248. The resulting spiral airflow prevents dust escape due to the high-pressure air leaving the drill bit.

[0034] FIGs. 6A and 6B are additional embodiments showing an alternative circular shape for an enclosure 400, 400’. In FIG. 6B protrusions 246 are placed in the same manner as shown in FIG. 5B to encourage spiral airflow that helps pick up dust despite the high-pressure air from the drill bit. The brush seal 244 ensures minimal dust escape in both variants.

[0035] FIG. 7 shows an example air amplifier 290 that includes an exhaust 292 and a suction inlet 294. A relatively small amount of compressed air is provided to the air amplifier through an air supply inlet 296 that goes through an annular chamber 295 and then is throttled through a thin annular channel 298 (which constricts the flow of the compressed air) employing the Venturi effect to increase the airflow velocity whilst changing the direction of airflow towards the exhaust 292. On exiting the annular channel 298 the compressed air enters a cylindrical chamber 299 at its outer edge. The air stream clings to the inside surface of the circumferential wall of the cylindrical chamber 299 because of the Coanda effect, the phenomena in which a jet flow attaches itself to a nearby surface and remains attached when the surfaces curves away from the initial jet direction This high velocity airflow creates a low pressure zone at the suction inlet 294, drawing in air at high velocities from the inlet 294 towards the exhaust 292. Dust created at the drilling surface is entrained with air which is pulled through the main axis of the cylindrical chamber 299. In the example arrangement of FIG. 3, the air amplifier 290 is provided so that the dust outlet of the enclosure is attached to the suction inlet 294, the compressed air is supplied via the pneumatic hose to the air inlet 298, and the exhaust 292 is provided as the main outlet to the dust collection receptacle. It will be appreciated by those skilled in the art that the invention has been illustrated by describing one or more specific aspects thereof, but is not limited to these aspects; many variations and modifications are possible, within the scope of the accompanying claims.

Claims

Claims1 . A system for removing dust during drilling operations, the system comprising: a device configured to be placed on a drilling surface; an air permeable dust collection receptacle; and a compressed air supply for supplying a compressed air flow into the device; wherein the device comprises: a housing; an air inlet, connected to the compressed air supply; and a main outlet connected to the dust collection receptacle; wherein the housing comprises: an enclosure for a drilling site at the drilling surface, the enclosure comprising an aperture configured to allow a drill bit to pass into the enclosure to reach the drilling site; and a first flow path for the compressed air flow from the compressed air supply, through the air inlet to the main outlet; wherein the enclosure further comprises a dust outlet allowing dust created at the drilling site to exit the enclosure, and wherein there is a connection between the dust outlet and the first flow path; wherein the housing is configured to constrict the first flow path upstream of the connection to the dust outlet and then dilate the first flow path at and / or downstream of the connection to the dust outlet, and wherein, in use, the compressed air flow following the first flow path causes a reduction in pressure at the dust outlet and in the enclosure, so that dust is drawn from the drilling site through the dust outlet and carried by the compressed air flow to the main outlet to be collected by the dust collection receptacle.

2. A system according to claim 1 , wherein the housing further comprises an air amplifier configured to perform the constriction and dilation of the first flow path and to provide the connection between the dust outlet and the first flow path, the air amplifier comprising: a cylindrical chamber having a circumferential wall extending between a first axial end and a second axial end along a main axis; andan annular channel positioned around the circumferential wall, wherein the air inlet is connected to the annular channel, the annular channel configured to direct the first flow path into the cylindrical chamber through a gap in the circumferential wall in a direction towards the second axial end; wherein the annular channel is angled relative to the main axis at an angle greater than 0° and less than 90°; wherein the dust outlet is connected to the first axial end of the cylindrical chamber, and the main outlet is connected to the second axial end of the cylindrical chamber; wherein the air amplifier is configured to restrict the first flow path through the annular channel, and to dilate the first flow path after the compressed air flow has entered the cylindrical chamber through the gap; wherein, in use, the compressed air flow following the first flow path through the annular channel experiences the Coanda effect when injected into the cylindrical chamber through the gap, such that the compressed air flow follows the circumferential wall of the cylindrical chamber and entrains the dust drawn through the dust outlet along the main axis towards the second axial end.

3. A system according to claim 1 or 2, wherein the enclosure further comprises a first seal around the aperture, the first seal configured to allow a drill bit to pass through the aperture and restrict movement of dust out through the aperture.

4. A system according to claim 3, wherein the first seal is a brush seal.

5. A system according to any preceding claim, wherein the enclosure further comprises a second seal configured to create a seal around the drilling site, the second seal acting between the enclosure and the drilling surface.

6. A system according to any preceding claim, wherein the aperture is a first aperture, and wherein the enclosure comprises a second aperture in line with the first aperture, and configured to sit on the drilling surface and be located over the drilling site.

7. A system according to any preceding claim, wherein the drilling operation is performed using a pneumatic drill, and the device is configured such thatcompressed air from the pneumatic drill escapes the drill bit in the drilling site, and is directed through the dust outlet and out of the main outlet by the reduction in pressure at the dust outlet and in the enclosure around the drilling site.

8. A system according to any preceding claim, wherein the aperture is located substantially centrally in the enclosure.

9. A system according to any preceding claim, wherein the enclosure is substantially circular around the aperture, and wherein the dust outlet is configured to direct dust substantially radially out of the enclosure.

10. A system according to any of claims 1 to 8, wherein the enclosure has a spiral shape with increasing radius centred around the aperture, and wherein the dust outlet is configured to direct dust circumferentially out of the enclosure at the widest radius of the spiral.

11. A system according to claim 10, wherein the spiral shape is configured such that dust being pulled out of the enclosure sticks to the curved surface of the enclosure after being pulled radially out of the drilling site.

12. A system according to any preceding claim, wherein the enclosure further comprises a plurality of protrusions provided around the aperture extending between a base of the enclosure and a top of the enclosure.

13. A system according to claim 12, wherein the plurality of protrusions are separated by gaps through which air and dust from the drilling site flow into the rest of the enclosure.

14. A system according to claim 12 or 13, wherein the gaps are of varying length.

15. A system according to claim 14, wherein the gaps comprise at least a first gap of a first length and a second gap of a second length, wherein the first length is more than double the second length.

16. A system according to any preceding claim, wherein the housing further comprises one or more surface contact portions on a wall of the housing facing the drilling surface.

17. A system according to any preceding claim, wherein the device is configured such that the weight of the device against the drilling surface is sufficient to cause the enclosure to seal against the drilling site.

18. A system according to any preceding claim, wherein the housing further comprises an electrical grounding point.

19. A system according to any preceding claim, wherein the air inlet comprises a switchable valve for selectively opening the air inlet to allow.

20. A system according to any preceding claim, wherein the device further comprises a protective cover configured to enclose the air inlet, the main outlet and the dust collection receptacle within the housing.

21. A system according to claim 20, wherein the protective cover is selectively operable to access the air inlet and / or main outlet and / or dust collection receptacle.

22. A device for removing dust during drilling operations, the device configured to be placed on a drilling surface; the device comprising: a housing; an air inlet for connection to a compressed air supply which supplies compressed air into the housing; and a main outlet for connection to an air permeable dust collection receptacle; wherein the housing comprises: an enclosure for a drilling site at the drilling surface, the enclosure comprising an aperture configured to allow a drill bit to pass into the enclosure to reach the drilling site; and a first flow path for the compressed air flow from the compressed air supply, through the air inlet to the main outlet;wherein the enclosure further comprises a dust outlet allowing dust created at the drilling site to exit the enclosure, wherein the dust outlet is connected to the first flow path; and wherein the housing is configured to constrict the first flow path upstream of the dust outlet and then dilate the first flow path at and / or downstream of the dust outlet.

Images