FLUID RECOVERY SUCTION HEAD

Abstract: A suction head (10) for lifting a flowable substance such as water, from a surface includes a base (12) for placement on the surface. The base (12) has a radially outer peripheral edge (14) in the shape of a circle. Recess (16) is formed centrally in the base (12) and has an outer edge (18) that is inboard of the edge (14), a plurality of slots (20) are formed in the base (12) and extend from edge (14) to edge (18), head (10) also includes a passage (22) having one end (24) that opens onto recess (16) and an opposite end (26) adapted for connection to a vacuum source or negative pressure source. Recess (16) has an upper planar surface (32) that is inclined relative to a horizontal reference plane. The slots (20) have a collective footprint area that is substantially the same as, or at least in the same order of magnitude as the footprint area of the recess (14). Further, the collective depth (D) of the slots (20) is substantially the same as or at least in the same order of magnitude as the diameter of hole (24).

Description: FLUID RECOVERY SUCTION HEAD Field of the Invention The present invention relates to a suction head for lifting a flowable substance from a surface or container, and to a recovery system incorporating said suction head. Background of the Invention The present invention was developed to meet the challenge of developing an environmentally sound industrial cleaning system particularly for cleaning surfaces, such as the walls of buildings, roads of road like surfaces; machinery; vehicles etc. Depending on the surface or item to be cleaned, a cleaning contractor may use a high pressure steam cleaner, high pressure water cleaner, or simply a hose using mains water pressure. The water, including detergents (if any) used in the cleaning and cleaning residues form waste water that flows over the ground to the nearest drain thus entering the drainage system. Depending on the nature of the drainage system, the waste water may be dumped to the ocean, leach into the ground, or be channelled to a water treatment system. In any case, allowing the water to drain away can lead to unnecessary environmental degradation. This has been recognised and some attempts have been made to recover the waste water or at least prevent it from entering the drainage system. For example, when cleaning cars or large vehicles, it is known to use a mat on which the vehicle is driven, the mat provided with a upstanding peripheral boarder so that water and detergents used during the cleaning collect on the mat and can then be pumped to a tank for transport to a water treatment site. While these mats adequately perform their intended function, they are often difficult to handle because of their size and weight. Also, such mats are limited in use to situations where they can be placed underneath the items to be cleaned. Therefore, they have no use at all in a large variety of cleaning events for example, steam cleaning a parking lot or the walls of a building. Summary of the Invention It is an object of the present invention to provide a suction head and a recovery system incorporating said head that can be used to draw or recover a flowable substance such as a liquid from a surface. According to a first aspect of the present invention there is provided a suction head for lifting a flowable substance from a surface, said suction head including at least: a base for placement on the surface, the base having a radially outer peripheral edge; a recess formed centrally in the base and having an outer edge inboard of said radially outer peripheral edge of said base; a plurality of slots formed in said base extending from said radially outer peripheral edge of said base toward and opening onto said recess; and a passage having one end that opens onto said recess and an opposite end adapted for connection to a vacuum source or a negative pressure source, said one end located inboard of said outer edge of said recess. Preferably, said slots extend in a radial direction. Preferably, said slots have a collective width substantially equal to or in the same order of magnitude as a diameter of said outer edge of said recess. Preferably, said slots have a collective depth substantially equal to or in the same order of magnitude as the diameter of said one end of said passage. Preferably, said recess includes a planar upper surface which is inclined relative to a horizontal reference plane. Preferably, said upper surface has an incline in the order of 1 :3. Preferably, said one end of said passage opens onto said upper planar surface. Preferably, said suction head further includes filter means supported in said base through which said flowable substance must pass when travelling from said slots into said passage. Preferably, said suction head further includes an annular seat formed adjacent and radially outward of said outer edge of said recess. Preferably, said filter is seated in said annular seat and said suction head further includes a retaining means for retaining said filter in said annular seat. Preferably, said retaining means is a clip or ring dimensioned to fit with a snap fit or an interference fit in said annular seat. Preferably, said suction head further includes an impeller seated in said recess. Preferably, said suction head further includes a non-return valve provided within, or in fluid communication with, said passage between said one end and a vacuum source or negative pressure source to which said suction head can be connected. Preferably, said base is circular. According to another aspect of the present invention there is provided a liquid recovery system for recovering a flowable substance from a surface or container, said system comprising at least: a suction head in accordance with the first aspect of this invention; and, a vacuum or negative pressure source coupled to said opposite end of said passage to provide a vacuum or suction source for drawing said substance through the slots and hole and directing the drawn substance to a waste collection or disposal means. Preferably the waste collection or disposal means is a tank. Preferably the system includes one or more transportable liquid barriers for laying on the surface to form a substantial seal on the surface preventing passage of the substance thereunder, whereby, in use, one or more of said barriers can be placed at appropriate locations to block off drainage points on the surface, or configured to defined a liquid confinement area on the surface in which the head is placed. Preferably each barrier comprises a tube made of a liquid impervious material and filled with a non-rigid ballast of a weight sufficient to hold the tube on the surface with a force sufficient to form a seal on the surface. Preferably, said ballast is a particulate material. While preferably the ballast is sand. Preferably, said tube is made from a rubber or rubber like material. Description of the Drawings An embodiment of the invention will now be described by way of example only with reference to the accompanying drawings in which: Figure 1 is a plan view of an embodiment of the suction head in accordance with the present invention; Figure 2 is an exploded transverse section view of the suction head depicted in Figure 1; Figure 3 is a plan view of a second embodiment of the suction head; Figure 4 is an exploded transverse section view of the suction head shown in Figure 3; Figure 5 is a plan view of a third embodiment of the suction head; Figure 6 is a plan view of an impeller incorporated in the suction head; Figure 7 is a schematic representation of an embodiment of the suction head incorporating the impeller shown in Figure 6; Figure 8 is a plan view of a fourth embodiment of the suction head; and Figures 9A & 9B depict transportable liquid barriers that can be used in a liquid recovery system incorporating the suction head. Detailed description of preferred embodiments Figures 1 and 2 depict a first embodiment of the suction head 10 for lifting a flowable substance such as water from a surface such as a roadway or parking lot. The suction head 10 includes a base 12 for placement on the surface. The base has a radially outer peripheral edge 14 which, in this instance, is in the configuration of a circle. A recess 16 is formed centrally in the base 12 and has an outer edge 18, which is inboard of the edge 14. A plurality of slots 20 are formed in the base 12 and extend from the edge 14 to the edge 18. The head 10 also includes a passage 22 having one end 24 in the form of a single hole that opens onto the recess 16. The hole 24 is located generally centrally in the recess 16 and inboard of the edge 18. An opposite end 26 of the passage 22 is adapted for connection to a vacuum source or a negative pressure source. When the head 10 is connected via end 26 to a vacuum source and the base 12 placed on a surface bearing water the suction head 10 is able to draw water from the surface through the slots 20 into the recess 16 and through the passage 20 for discharge at a remove location. The slots 20 are made of a depth D to form a barrier to the passage of foreign matter of a predetermined size through the slots 20 into the region 16 and subsequently through the passage 22. For example, the depth D may be in the order of 4 - 5 millimetres to prevent the ingress of foreign matter having a dimension greater than 5 millimetres. This would preclude items such as cigarette butts and stones of a greater size from passing through the slots 20. A plurality of transversely extending holes 28 are provided in the suction head 10 between adjacent slots 20. The purpose of the holes 28 is to reduce the weight of the suction head 10. The slots 20 have a collective (ie, cumulative) width W that is substantially the same as, and at least the same order of magnitude as diameter of outer edge 18 of the recess 16. Additionally, the slots have a collective (ie, cumulative) depth D that is substantially the same as or at least in the same order of magnitude as the diameter of the hole 24. Such relative configuring of the slots 20 with the recess 16 and hole 24 optimise the efficiency of the suction head 10. As is most apparent from Figure 2, the recess 16 is provided with an upper planar surface 32. The planar surface 32 lies in an inclined plane having a gradient in the order of 1 :3. An annular set 34 is formed adjacent to and radially outward from the edge 18. Seat 34 includes an outer circumferential face 36 that extends axially to form an inner radial edge 37 of slots 20. Edges 14 and 37 are coplanar and between them define an annular band in which the slots 20 are formed. Due to the inclination of the surface 32 when the head 10 is in use, there will be a pressure gradient or differential across the recess 16. It is believed that this is beneficial in the operation of the head 10 by providing either a vortex action on the liquid being lifted, or a pulsating or diaphragm effect to assist in lifting the liquid from the surface. To further assist in reducing the ingress of debris beyond a predetermined particle size through the passage 22, a filter 38 in the form of a mesh screen is placed in the recess 16 with the peripheral edges of the filter 38 resting on the seat 34. A locking ring or circlip 40 is disposed over the filter 38 to hold it within the recess 16. Any known arrangement can be used to mount the ring 40 to the head 10 such as, for example, forming the ring 40 to provide an interference fit against the face 36 or, forming the ring 40 as a circlip to seat inside a groove (not shown) formed about the face 36. Figures 3 and 4 depict a second embodiment of the head 10' in which like reference numbers denote like features. The head 10' differs in the shape and configuration of the base 12 and most notably, is provided with only four slots 20 rather than eight as depicted in Figures 1 and 2. In a general sense, the head 10 is in the form of a plate whereas the head 10' has a general shape of a conical frustum with an extended constant diameter end. Typically the head 10 will have a larger diameter than the head 10' and would be used in different applications. For example, the head 10 would typically be used for recovering say water from a parking lot whereas the head 10' may be used for recovering oil or petrol from a drum, tank or other container. Figure 5 depicts a further embodiment 10" of the suction head. The embodiment 10" differs in substance from the embodiment 10 by virtue of the configuration of the end 24 of the passage 22 that opens onto the recess 16. With the head 10" the end 24 is configured as four separate holes 24' that are contained within a generally elliptical sub- area within recess 16. The purpose of providing four separate holes 24' is to assist in equalising pressure available to the slots 20. In yet a further embodiment pictures in Figures 6 and 7, an impeller 42 is incorporate into the suction head 10'". The impeller 42 has an annular periphery 44, which supports a plurality (in this case four) impeller blades 46. A plurality of ball bearings 48 are retained in and distributed about the periphery 44. The impeller 42 is seated on the seat 34. If the filter 38 is incorporated in the head the impeller 42 sandwiched between the filter 38 and the seat 34. The bearings 48 allow the impeller 42 to rotate about its axis. When a vacuum source or negative pressure source is attached to the passage 22, the impeller 42 is caused to rotate by virtue of a pressure differential. The purpose of the impeller 42 is to also assist in equalising pressure distribution to the slots 20. Figure 8 depicts a further embodiment of the suction head 10"". This embodiment differs from that depicted in Figure 5 in substance by the shape of the outer peripheral edge 14 of the head. In this embodiment, the peripheral edge 14 is of octagonal shape thereby providing eight straight edges about the periphery of the head 10"". This embodiment may be particularly useful for use as a head in a wet or steam carpet cleaning system where it is often desirable to have square edges on the suction head in order to enable cleaning of a carpet adjacent a wall. The embodiment of the suction head depicted in Figures 1 - 8 can form part of a larger liquid recovery system for recovering liquid from a surface or container. The liquid recovery system includes the suction head 10 and a vacuum source, negative pressure source or pump that is coupled at its suction end to the passage 22. The liquid recovery system would also include one or more transportable liquid barriers 50 as shown in Figures 8A and 8B, for laying on a surface to form a substantial seal on the surface to prevent the passage of water thereunder. In this way, one or more of the barriers 50 can be used to block off natural or artificial drainage points, or to be configured to define a liquid confinement area on the surface on which the head 10 is place. Each barrier 50 comprises a tube 52 of liquid impervious, and preferably flexible material filled with a non-rigid ballast 54 of a sufficient weight to hold the tube 52 on the surface with sufficient force to form a seal on the surface. Ideally, the ballast 54 is in the form of a particulate material such as sand. End caps (not shown) are placed at each end of the tubes 52 to seal the ends and prevent ingress of liquid into the ballast 54. The barriers 50 can be easily manipulated into any desired shape. They can also be made to any length, although it is envisage that they would be made of one or two standard lengths, for example three meters and six meters. In this way a plurality of barriers 50 can be placed in a slightly overlapping end to end arrangement to form a liquid barrier of a required shape and/or configuration. A particularly suitable material from which the tube 52 can be made is polyethylene rubber or SBR latex, preferably having a wear and chemical resistant skin. Now that embodiments of the present invention have been described in detail it will be apparent to those skilled in the appropriate arts that numerous modifications and variations may be made without departing from the basic inventive concepts. For example, the suction heads 10, 10', 10" and 10'" are depicted as having a base 12, which is of a circular shape. However, the base can be made in other shapes. Also, a non-return valve can be placed in the passage 24, which allows flow in the direction from hole 24 to end 26 but prevents a flow in the reverse direction. The head 10 can be made from a wide variety of materials depending on the intended application. For example, 301 stainless steal or titanium is ideal if the head 10 is to be used in a corrosive environment. However, plastics materials may also be used in the construction of the head 10 say for example when used in relation to water. Further, while the above description describes use of the head 10 in relation to the recovery of liquid it can be used for the recovery of other flowable substances such as particulate materials and powders, for example, cereal grains such as wheat or rice. When used in such embodiments, the filter 38 may be removed or at least configured to ensure that the desired particles can pass therethrough. All such modifications and variations together with others that would be obvious to a person of ordinary skill in the art are deemed to be within the scope of the present invention the nature of which is to be determined from the above description and the appended claims .

Claims: CLAIMS The Claims Defining the Invention as are Follows: 1. A suction head for lifting a flowable substance from a surface, said suction head including at least: a base for placement on the surface, the base having a radially outer peripheral edge; a recess formed centrally in the base and having an outer edge inboard of said radially outer peripheral edge of said base; a plurality of slots formed in said base extending from said radially outer peripheral edge of said base to said outer edge of said recess; and a passage having one end that opens onto said recess and an opposite end adapted for connection to a vacuum source or a negative pressure source, said one end located inboard of said outer edge of said recess. 2. The suction head according to claim 1, wherein said slots have a collective width substantially equal to or in the same order of magnitude as a diameter of said outer edge of said recess. 3. The suction head according to claim 2, wherein said slots have a collective depth substantially equal to or in the same order of magnitude as the diameter of said one end of said passage. 4. The suction head according to anyone of claims 1 to 3, wherein said recess includes a planar upper surface which is inclined relative to a horizontal reference plane. 5. The suction head according to claim 4, wherein said upper surface has an incline in the order of 1:3. 6. The suction head according to claim 4 to 5, wherein said one end of said passage opens onto said upper planar surface. 7. The suction head according to anyone of claims 1 to 6, further including filter means supported in said base through which said flowable substance must pass when travelling from said slots into said passage. 8. The suction head according to anyone of claims 4 to 8, further including an annular seat formed adjacent and radially outward of said outer edge of said recess. 9. The suction head according to claim 8, wherein said filter is seated in said annular seat and said suction head further includes a retaining means for retaining said filter in said annular seat. 10. The suction head according to claim 10, wherein said retaining means is a clip or ring dimensioned to fit with a snap fit or an interference fit in said annular seat. 11. The suction head according to anyone of claims 1 to 10, further including an impeller seated in said recess. 12. The suction head according to anyone of claims 1 to 11, further including a nonreturn valve provided within, or in fluid communication with, said passage between said one end and a vacuum source or negative pressure source to which said suction head can be connected. 13. The suction head according to anyone of claims 1 to 12, wherein said base is circular. 14. The suction head according to anyone of claims 1 to 13, wherein said slots extend in a radial direction. 15. A liquid recovery system for recovering a flowable substance from a surface or container, said system comprising at least: a suction head in accordance with any one of claims 1 to 14 and, a vacuum or negative pressure source coupled to said opposite end of said passage to provide a vacuum or suction source for drawing said substance through the slots and hole and directing the drawn substance to a waste collection or disposal means. 16. The system according to claim 15, further including one or more transportable liquid barriers for laying on the surface to form a substantial seal on the surface preventing passage of the substance thereunder, whereby, in use, one or more of said barriers can be placed at appropriate locations to block off drainage points on the surface, or configured to defined a liquid confinement area on the surface in which the head is placed. 17. The system according to claim 15, wherein each barrier comprises a tube made of a liquid impervious material and filled with a non-rigid ballast of a weight sufficient to hold the tube on the surface with a force sufficient to form a seal on the surface. 18. The system according to claim 17, wherein said ballast is a paniculate material. 19. The system according to claim 18, wherein said tube is made from a rubber or rubber like material.

Inventors: OLSEN GARY, OLSEN, GARY
Applicants: OLSEN GARY, OLSEN, GARY
Application year: 2000
Main classification: A47L5
IPC codes: A47L9, B08B17, E01H1