Patent Application
20170241061
The present invention relates to a treatment apparatus which employs a solid particulate material (also referred to herein as “a multiplicity of solid particles”). The treatment apparatus can be used for the cleaning of soiled substrates and may require the use of only limited quantities of energy, water and detergent as compared with conventional cleaning apparatus, and in particular as compared with conventional washing machines. More particularly, the invention is concerned with an apparatus comprising a separating device for intercepting and/or capturing foreign objects in a circulation path. The separating device also provides a transfer flow path for the passage of the solid particulate material within the treatment apparatus. The present invention also relates to a method of treating one or more substrates with a multiplicity of solid particles using said apparatus.
Aqueous cleaning processes are a mainstay of conventional domestic and industrial textile fabric cleaning methods. On the assumption that the desired level of cleaning is achieved, the efficacy of such conventional processes is usually characterised by their levels of consumption of energy, water and detergent. In general, the lower the requirements with regard to these three components, the more efficient the washing process is deemed. The downstream effect of reduced water and detergent consumption is also significant, as this minimises the need for disposal of aqueous effluent, which is both extremely costly and detrimental to the environment.
Conventional washing processes involve aqueous submersion of fabrics followed by aqueous soil suspension, soil removal and water rinsing. In general, within practical limits, the higher the level of energy (or temperature), water and detergent which is used, the better the cleaning. One key issue, however, concerns water consumption, as this sets the energy requirements (in order to heat the wash water), and the detergent dosage (to achieve the desired detergent concentration). In addition, the water usage level defines the mechanical action of the process on the fabric, which is another important performance parameter; this is the agitation of the cloth surface during washing, which plays a key role in releasing embedded soil. In aqueous processes, such mechanical action is provided by the water usage level in combination with the drum design for any particular washing machine. In general terms, it is found that the higher the water level in the drum, the better the mechanical action. Hence, there is a dichotomy created by the desire to improve overall process efficiency (i.e. reduce energy, water and detergent consumption), and the need for efficient mechanical action in the wash.
In the light of the challenges which are associated with aqueous washing processes, the present applicant has previously devised a new approach to this problem. The method developed significantly reduced the requirement for the use of large volumes of water, but was still capable of providing an efficient means of cleaning and stain removal from textile fabric substrates, whilst also yielding economic and environmental benefits.
Thus, in WO2007/128962 there is disclosed a method and formulation for cleaning a soiled substrate, the method comprising the treatment of the moistened substrate with a formulation comprising a multiplicity of polymeric particles, wherein the formulation is free of organic solvents. The substrate may be wetted so as to achieve a substrate to water ratio of between 1:0.1 to 1:5 w/w, and optionally, the formulation may additionally comprise at least one cleaning material, which typically comprises a surfactant, which most preferably has detergent properties. The substrate may comprise a textile fibre. The polymeric particles may, for example, comprise particles of polyamides, polyesters, polyalkenes, polyurethanes or their copolymers, a particular example being nylon beads.
Following the development of this method the present applicant further devised an apparatus specially adapted to clean soiled substrates by virtue of recirculation of the polymeric particles. Thus, in WO2011/098815, the present applicant provided an apparatus for use in the cleaning of soiled substrates, the apparatus comprising housing means having a first upper chamber with a rotatably mounted cylindrical cage mounted therein and a second lower chamber located beneath the cylindrical cage, and additionally comprising at least one recirculation means, access means, pumping means and a multiplicity of delivery means, wherein the rotatably mounted cylindrical cage comprises a drum having perforated side walls where up to 60% of the surface area of the side walls comprises perforations comprising holes having a diameter of no greater than 25.0 mm.
Although the method and apparatus disclosed in WO2007/128962 and WO2011/098815 provided considerable improvements for the cleaning of soiled substrates, certain complications can arise when adopting a cleaning treatment based on the circulation of formulations comprising solid particulate material and wash water.
One problem which may be experienced is the blockage of the pumping device used for the circulation of the solid particulate material. This may occur if foreign objects of undesired size or shape make their way into the washload and pass through the drum along a circulation path to inhibit the pumping device. This can render the pumping device inoperative until such blockage is removed, which may require the intervention of a skilled operative.
Furthermore, it is possible for long thin foreign objects to protrude through the holes often present in the drum. This can result in the drum jamming, in scraping the outer tub which surrounds the drum or in snapping, cutting or grinding the foreign object so forming smaller foreign objects that can pass along a circulation path to inhibit or damage the pumping device.
The above noted problems may be particularly acute in workplaces where health and safety considerations prevent the users of commercial washing machines from inspecting the laundry for foreign objects. Consequently, the laundry has to enter the washing machine without any prior inspection whereby nails, screws, oyster forks and the like remain in the pockets of many garments.
Devices for intercepting foreign objects in the wash liquid of conventional washing machines are known. By means of example, U.S. Pat. No. 7,406,843 discloses a separator comprising an array of regularly spaced fins oriented upstream of a recirculation pump for intercepting foreign objects in the wash liquid.
However, the separator device of U.S. Pat. No. 7,406,843, along with similar devices in this field, disclose arrangements which would restrict, inhibit or altogether block the flow of solid particulate material through the device thus preventing their efficient circulation.
The present disclosure seeks to provide an apparatus for use in the treatment of substrates with a solid particulate material that can ameliorate or overcome one or more of the above-noted problems associated with the prior art.
Particularly, there is desired an apparatus which can alleviate problems associated with the accumulation of foreign objects in, or in proximity to, a circulation pathway for solid particulate material. Additionally there is desired an apparatus that can intercept and/or capture foreign objects in a circulation path before they enter the pumping device used for the circulation of the solid particulate material. Furthermore, there is desired an apparatus for intercepting and/or capturing one or more foreign objects in a circulation path that does not substantially inhibit or restrict the flow of solid particulate material therethrough.
According to a first aspect of the present invention, there is provided an apparatus for treating one or more substrates with a multiplicity of solid particles comprising:
a rotatably mounted drum arranged to contain said multiplicity of solid particles and said one or more substrates during treatment of the one or more substrates;
a collecting volume for collecting said multiplicity of solid particles exiting the drum;
a circulation path for conveying said multiplicity of solid particles from the collecting volume to the drum, the circulation path having a downward portion in which the multiplicity of solid particles move along a downward flow path;
a separating device arranged in said downward portion of the collecting path for intercepting and/or capturing one or more foreign objects while permitting flow of said multiplicity of solid particles along the circulation path, the separating device comprising:
a sloping surface and a transfer flow path for said solid particles said transfer flow path permitting flow of said multiplicity of solid particles between an upper side of said separating device and a portion of the circulation path external to the separating device,
wherein said transfer flow path comprises an envelope extending from an inlet opening to an outlet opening, and bounded by a portion of the sloping surface and at least one envelope wall
and wherein within the envelope between the inlet opening and the outlet opening no straight line longer than a predetermined length can extend without intersecting the at least one envelope wall or sloping surface, said predetermined length being less than a maximum dimension of the smallest foreign object which the separating device is configured to intercept or capture.
Thus, advantageously, the apparatus of the present invention comprises a separating device configured to intercept and/or capture one or more foreign objects from a circulation path and which provides a transfer flow path for solid particulate material. The separating device can thus provide a means of preventing damage to the components responsible for circulating materials along a flow pathway within the apparatus but without adversely affecting the flow of said solid particulate material therethrough.
The multiplicity of solid particles is also referred to herein as a solid particulate material. For the avoidance of doubt, the multiplicity of solid particles is distinguished from, and should not be construed as being, a conventional washing powder (that is laundry detergent in powder form). Washing powder is generally soluble in the wash water and is included primarily for its detergent qualities. The washing powder is disposed of during the wash cycle since it is sent to drain in grey water along with removed soil. In contrast, a significant function of the multiplicity of solid particles referred to herein is a mechanical action on the substrate which enhances the treatment performed on the substrate. Preferably, the multiplicity of solid particles is retained within the apparatus of the invention and used in a plurality of treatment procedures.
Preferably said transfer flow path permits flow of said multiplicity of solid particles between an upper side and an underneath side of said separating device.
Preferably, the or each transfer flow path is arranged at or proximate a lower marginal edge portion of the sloping surface.
Preferably the apparatus comprises a plurality of said transfer flow paths.
Preferably the apparatus comprises at least one array of said transfer flow paths, more preferably from 2 to 10, even more preferably from 2 to 8 and especially 2, 4, 6 or 8 arrays of said transfer flow paths. The present inventors have found that the use larger numbers of arrays helps to prevent blockages and can spread the solid particle more uniformly in a collecting volume (which is typically a sump). This has a further advantage of allowing better transfer of the solid particles along a circulation path especially when circulation is achieved by means of a pump. Preferably said at least one array is a linear array of said transfer flow paths.
Preferably the envelope comprises, and more preferably is bounded by, opposed side walls upstanding from the sloping surface and having a marginal edge distal from the sloping surface, and a closure wall extending between the respective marginal edges of the side walls.
Preferably said opposed side walls are spaced apart by a distance that is smaller than said predetermined length.
Preferably the apparatus comprises a common closure wall extending between respective marginal edges of a plurality of the side walls.
Preferably the inlet and outlet openings are bounded by the sloping surface, and respective edges of the side walls and the closure wall.
Preferably each side wall extends laterally outwardly with respect to a lower marginal edge of the sloping surface.
Preferably the inlet opening is arranged at an upper side and the outlet opening is arranged at an underneath side of the sloping surface.
Preferably the inlet opening is defined by an upper side of the sloping surface and respective edges of the side walls and the closure wall and the outlet opening is defined by an underneath side of the sloping surface and respective edges of the side walls and the closure wall.
Preferably the closure wall defines a curved internal surface of the transfer flow path between the inlet opening and the outlet opening.
Thus, preferably, the solid particles proceed along a curved path as a result of the curved internal surface of the transfer flow path which can facilitate an uninhibited flow of solid particles through the separating device.
Preferably the respective side walls are substantially planar. Preferably said respective side walls are parallel to each other. Preferably said respective side walls are perpendicular to said sloping surface.
Preferably the transfer flow path extends around a lower marginal edge of the sloping surface.
Preferably the apparatus comprises a particle directing element which is unitary with said closure wall wherein said particle directing element is arranged to promote movement of solid particles towards the inlet opening of the transfer flow path.
Preferably the respective side walls are non-planar and extend upwardly from the sloping surface to respective top marginal edges and the closure wall extends above the sloping surface between said respective top marginal edges.
Preferably the inlet opening is defined by an upper side of the sloping surface, an underside of the closure wall and respective upstream edges of the side walls and the outlet opening is defined by an the upper side of the sloping surface an underside of the closure wall and respective downstream edges of the side walls. The terms “upstream” and “downstream” edges are used with respect to the flow direction of the multiplicity of solid particles.
Preferably the side walls comprise first and second planar side wall panels extending from a common edge in a “v” or chevron configuration.
Preferably the separating device comprises one or more internal surfaces between said inlet opening and said outlet opening configured to cause a change in direction of the flow of solid particles within the transfer flow path, such that solid particles entering the inlet opening along a first direction leave via the outlet opening in a second direction that is different to the first direction.
Preferably the apparatus comprises a further transfer flow path for said solid particles arranged above said transfer flow path, said further transfer flow path permitting flow of said multiplicity of solid particles between an upper side of said separating device and a portion of the circulation path external to the separating device,
wherein said further transfer flow path arranged above said transfer flow path comprises a further envelope extending from an inlet opening to an outlet opening, and bounded by a sloping floor surface and at least one envelope wall,
and wherein within the further envelope between the inlet opening and the outlet opening no straight line longer than a predetermined length can extend without intersecting the at least one envelope wall or sloping floor surface, said predetermined length being less than a maximum dimension of the smallest foreign object which the separating device is configured to intercept or capture.
The further transfer flow path arranged above said transfer flow path can comprise any feature or permitted combination of the features described above in relation to the first mentioned transfer flow path, with any adaption(s) as is (are) necessary consequent upon the location of the further transfer flow path. For example, in the context of the further transfer flow path, references above to the sloping surface can be taken as references to the sloping floor surface.
Advantageously, the provision of a further solid transfer flow path above said transfer flow path provides an alternative route for the solid particles should the lower (first) transfer flow path become blocked. Furthermore, the provision of said further solid transfer flow path can also allow a higher flow rate of solid particles through the separating device.
Preferably said further transfer flow path arranged above said transfer flow path permits flow of said multiplicity of solid particles between an upper side and an underneath side of said separating device.
Preferably the apparatus comprises a plurality of said further transfer flow paths.
Preferably the apparatus comprises at least one array of said transfer flow paths and at least one array of said further transfer flow paths arranged above the said array of transfer flow paths. Preferably, the apparatus comprises at least one linear array of said transfer flow paths and at least one linear array of said further transfer flow paths arranged above the said linear array of transfer flow paths.
Preferably said at least one array or said at least one linear array of said transfer flow paths and said at least one array or said at least one linear array of said further transfer flow paths are arranged in stacked relation.
Preferably the apparatus comprises a further transfer flow path for said solid particles laterally offset from said transfer flow path, said further transfer flow path permitting flow of said multiplicity of solid particles between an upper side of said separating device and a portion of the circulation path external to the separating device,
wherein said further transfer flow path laterally offset from said transfer flow path comprises a further envelope extending from an inlet opening to an outlet opening, and bounded by a sloping floor surface and at least one envelope wall,
wherein said inlet opening of said further envelope is above said inlet opening of said envelope of said transfer flow path,
and wherein within the further envelope between the inlet opening and the outlet opening no straight line longer than a predetermined length can extend without intersecting the at least one envelope wall or sloping floor surface, said predetermined length being less than a maximum dimension of the smallest foreign object which the separating device is configured to intercept or capture.
Thus, preferably, the provision of a further laterally offset transfer flow path can facilitate an improved efficiency of flow of solid particles through the apparatus.
The further transfer flow path laterally offset from said transfer flow path can comprise any feature or permitted combination of the features described above in relation to the first mentioned transfer flow path, with any adaption(s) as is (are) necessary consequent upon the location of the further transfer flow path. For example, in the context of the further transfer flow path laterally offset from said transfer flow path, references above to the sloping surface can be taken as references to the sloping floor surface.
Preferably said outlet opening of said further envelope is above said outlet opening of said envelope of said transfer flow path.
Preferably said outlet opening of said further envelope is above said inlet opening of said envelope of said transfer flow path. Alternatively said outlet opening of said further envelope is below said inlet opening of said envelope of said transfer flow path.
Preferably said sloping floor extends laterally from an external surface of said closure wall. The closure wall can be that of said first mentioned transfer flow path or a transfer flow path located directly below an upper laterally offset transfer flow path.
Preferably said further transfer flow path laterally offset from said transfer flow path permits flow of said multiplicity of solid particles between an upper side and an underneath side of said separating device.
Preferably the apparatus comprises a plurality of said further transfer flow paths.
Preferably the apparatus comprises at least one array of said transfer flow paths and at least one array of said further transfer flow paths laterally offset from the said array of transfer flow paths. Preferably, the apparatus comprises at least one linear array of said transfer flow paths and at least one linear array of said further transfer flow paths laterally offset from the said linear array of transfer flow paths.
Preferably said apparatus comprises at least one additional sloping surface and an additional transfer flow path arranged at a lower marginal portion of the or each additional sloping surface, said additional transfer flow path permitting flow of said multiplicity of solid particles between an upper side of said separating device and a portion of the circulation path external to the separating device,
wherein the uppermost limit of the sloping surfaces extends from a common point or edge,
and wherein the or each additional transfer flow path comprises a further envelope extending from an inlet opening to an outlet opening, and bounded by the or each additional sloping surface and at least one envelope wall,
and wherein within the further envelope between the inlet opening and the outlet opening no straight line longer than a predetermined length can extend without intersecting the at least one envelope wall or second sloping surface, said predetermined length being less than a maximum dimension of the smallest foreign object which the separating device is configured to intercept or capture.
In preferred arrangements comprising at least one additional sloping surface, no gaps are holes are present between the respective sloping surfaces. Thus in some preferred arrangements the sloping surface and additional sloping surface(s) present a continuous uninterrupted upper face on which the solid particulate material can impinge. Such a separating device is illustrated in a non-limiting manner by
The separating device can comprise a plurality of additional sloping surfaces and a plurality of additional transfer flow paths arranged at a lower marginal portion of each additional sloping surface, said additional transfer flow paths permitting flow of said multiplicity of solid particles between an upper side of said separating device and a portion of the circulation path external to the separating device. In this arrangement, and as described above, each additional transfer flow path comprises a further envelope extending from an inlet opening to an outlet opening, and bounded by each additional sloping surface and at least one envelope wall, and wherein within the further envelope between the inlet opening and the outlet opening no straight line longer than a predetermined length can extend without intersecting the at least one envelope wall or additional sloping surface, said predetermined length being less than a maximum dimension of the smallest foreign object which the separating device is configured to intercept or capture. In this arrangement, the uppermost limit of all sloping surfaces does not necessarily extend from a common point or edge. In this arrangement, it is preferred that at least two sloping surfaces extend from a common point or edge and the separating device comprises at least one additional sloping surface which does not extend from said common point or edge. In a preferred arrangement, the separating device comprises two sloping surfaces which extend from a common point or edge and further comprises two additional sloping surfaces which do not extend from said common point or edge. Such a separating device is illustrated in a non-limiting manner by
Thus, the solid particles can be provided with alternative routes at different sides or regions of the separating device from which to exit. This can ensure that a localised build-up of solid particles in a single region of the collecting volume that may inhibit the efficiency of any circulation pathway is avoided.
The additional transfer flow path(s) can comprise any feature or permitted combination of the features described above in relation to the first mentioned transfer flow path, with any adaption(s) as is (are) necessary consequent upon the location of the additional transfer flow path. For example, in the context of the additional transfer flow path(s), references above to the sloping surface can be taken where contextually appropriate as references to an or each additional sloping surface.
Preferably said sloping surface is configured to direct said solid particles into said inlet opening of said transfer flow path and the or each additional sloping surface is configured to direct said solid particles into said inlet opening of said the or each additional transfer flow path.
Preferably said apparatus comprises a first sloping surface and a second sloping surface wherein the first and second sloping surfaces extend at their uppermost limit from a common edge.
Preferably said collecting volume comprises a sump.
Preferably said separating device is located below said drum.
Preferably said separating device is arranged above said collecting volume in said circulation path.
Preferably said circulation path comprises a pumping device and said separating device is located in the circulation path after the drum before said pumping device, with respect to the circulation direction
Preferably said solid particles are recirculated from the collecting volume to the drum via said pumping device.
Preferably said one or more foreign objects have a length dimension and a width dimension wherein said length dimension is greater than said width dimension and preferably wherein said length dimension is at least four times greater than said width dimension.
Preferably said one or more foreign objects are elongated foreign objects such as nails, screws, bolts, paper clips, toothpicks, hypodermic needles, pencils, pens, keys, cotton buds, needles, small hand tools or parts thereof, pins, hairpins, grips, cutlery (such as knives, forks (e.g. oyster forks) and spoons) and the like.
Preferably the predetermined length (i.e. the maximum dimension of said one or more foreign objects) is at least 30 mm. The predetermined length can be at least 50 mm, or at least 70 mm or at least 100 mm or at least 120 mm.
Preferably said drum comprises a rotatably mounted cylindrical cage comprising a perforate cylindrical wall. Preferably the perforations of the cylindrical wall comprise holes having a diameter of no greater than 25 mm. Preferably, said perforations comprise holes having a diameter of from about 2 to 25 mm, more preferably said perforations comprise holes having a diameter of from about 2 to about 10 mm, even more preferably said perforations comprise holes having a diameter of from about 4 to about 10 mm, especially said perforations comprise holes having a diameter of from about 5 to about 8 mm. Optionally said perforations comprise holes having a diameter of from about 2 to 3 mm.
Preferably up to 60% of the surface area of the cylindrical side wall of the drum can comprise perforations, more preferably no more than 50% of the surface area of the side walls comprises perforations and especially no more than 40% of the surface area of the side walls comprises perforations.
Preferably at least 5% of the surface area of the cylindrical side wall of the drum comprises perforations, more preferably at least 10% of the surface area of the cylindrical side wall of the drum comprises perforations and especially at least 20% of the surface area of the cylindrical side wall of the drum comprises perforations.
Preferably the solid particles have an average particle diameter of from 1.0 mm to 10 mm, more preferably the solid particles have an average diameter of from 2.0 mm to 8.0 mm and especially the solid particles have an average diameter of from 2.0 mm to 6.0 mm. The effective average diameter can also be calculated from the average volume of a particle by simply assuming the particle is a sphere. The average is preferably a number average. The average is preferably performed on at least 10, more preferably at least 100 particles and especially at least 1000 particles.
Preferably the solid particles have a length of from 1.0 mm to 10 mm, more preferably a length of from 2.0 mm to 8.0 mm and especially a length of from 2.0 mm to 6.0 mm. The length can be defined as the maximum 2 dimensional length of each 3 dimensional solid particle. The average is preferably a number average. The average is preferably performed on at least 10, more preferably at least 100 particles and especially at least 1000 particles.
Preferably said multiplicity of solid particles comprise cylindrical, substantially ellipsoidal, spheroidal or substantially spherical particles.
Preferably the apparatus is a washing machine, which can be a commercial or domestic washing machine.
Optionally the apparatus is a commercial washing machine.
Optionally the apparatus is a domestic washing machine. A domestic washing machine is a washing machine configured for location in a private dwelling such as a house or apartment.
Preferably said rotatably mounted drum is configured for rotation about a substantially horizontal axis.
Preferably the substrate is a textile material, in particular one or more garments or domestic or hotel linens such as, bed linen, towels, napery or the like.
Preferably the separating device is removable from the apparatus via an aperture formed in an external housing of the apparatus. Thus, preferably, said separating device can be easily removed from the apparatus for routine inspection and/or maintenance.
Preferably, said aperture is closed by a panel wherein said panel comprises a window or transparent material.
Preferably the multiplicity of solid particles is in the form of a multiplicity of beads. Preferably said multiplicity of solid particles is in the form of cylindrical, ellipsoidal, spheroidal or spherical beads.
Preferably the solid particles are reused one or more times for treatment of substrates in, with or by the apparatus of the invention.
Preferably the multiplicity of solid particles comprises or consists of a multiplicity of polymeric particles.
Optionally the multiplicity of solid particles comprises or consists of a multiplicity of non-polymeric particles.
Preferably the multiplicity of solid particles comprises or consists of a mixture of polymeric solid particles and non-polymeric solid particles.
Preferably the polymeric particles can be are particles of polyalkenes, polyamides, polyesters, polysiloxanes, polyurethanes or copolymers thereof.
Optionally the polymeric particles comprise particles selected from particles of polyalkenes or copolymers thereof.
Preferably the polymeric particles comprise particles of polyamide or polyester or copolymers thereof.
Preferably the polyester particles comprise particles of polyethylene terephthalate or polybutylene terephthalate.
Preferably the polyamide particles comprise particles of nylon. Preferably said nylon can comprise Nylon 6 or Nylon 6,6.
Preferably the non-polymeric particles comprise particles of glass, silica, stone, wood, metals or ceramic materials.
Preferably said solid particles are conveyed along a portion of said circulation path with a carrier fluid. The carrier fluid is an aqueous medium. Preferably the carrier fluid is wash liquor. As described herein, “wash liquor” can comprise water or water when combined with at least one cleaning agent such as a detergent composition and/or any further additives as detailed further hereinbelow.
According to a second aspect of the invention there is provided a separating device for intercepting and/or capturing one or more foreign objects, the separating device comprising:
a sloping surface and a transfer flow path for permitting the flow of a multiplicity of solid particles between an upper side of said separating device and a portion of a circulation path external to the separating device,
wherein said transfer flow path comprises an envelope extending from an inlet opening to an outlet opening, and bounded by a portion of the sloping surface and at least one envelope wall
and wherein within the envelope between the inlet opening and the outlet opening no straight line longer than a predetermined length can extend without intersecting the at least one envelope wall or sloping surface, said predetermined length being less than a maximum dimension of the smallest foreign object which the separating device is configured to intercept or capture.
According to a third aspect of the invention there is provided a method of treating one or more substrates with a multiplicity of solid particles using the apparatus as described in accordance with the first aspect of the invention.
Preferably said method is a method of cleaning said one or more substrates.
Preferably said one or more substrates are textile materials, in particular one or more garments or domestic or hotel linens such as, bed linen, towels, napery or the like.
According to a fourth aspect of the invention there is provided a method of intercepting and/or capturing foreign objects from a circulation path using the apparatus as described in accordance with the first aspect of the invention or the separating device described in accordance with the second aspect of the invention.
For a better understanding of the invention and to show how the same may be carried into effect, reference will be made, by way of example only, to the following drawings, in which:—
The present applicant has addressed the issues associated with using an apparatus to treat substrates with a solid particulate material and particularly the problems associated with foreign objects blocking or inhibiting the flow of the solid particulate material within the apparatus.
Referring now to the drawings, an apparatus 100 according to the invention typically comprises an external housing or casing 10 which may comprise a front face 10a, rear face 10b, top face 10c, bottom face 10d and side faces 10e, 10f.
The apparatus 100 further includes a perforate drum or cage 12. In use of the apparatus 100 the drum 12 contains the substrate(s) being treated, for example cleaned. The drum 12 may preferably be mounted for rotation about a horizontal or substantially horizontal axis and the substrate being treated is brought into contact with solid particulate material, water and such other treatment additives as may be desirable within the drum 12.
The drum 12 has an opening 16 through which the substrate(s) to be treated can be loaded into the drum 12 and through which the treated substrate(s) can be removed after the treatment process. The opening 16 is arranged at the front side of the apparatus and a corresponding opening is formed in the front face 10a of the external housing 10. In use of the apparatus 100, the drum opening 16 is closed by a door 18. The door 18 may conveniently be hingedly mounted for movement between open and closed configurations. When the door 18 is moved to an open position, access is permitted to place one or more substrates for treatment inside the drum 12. When the door 18 is moved to a closed position, the treatment apparatus 100 is sealed. Apparatus 100 may further comprise an internal housing or tub 14 which surrounds the drum 12 and which (when the door 18 is in its closed position) forms a fluid tight space around the drum 12.
The drum 12 can be in the form of a rotatably mounted cylindrical cage comprising a foraminous or perforate cylindrical wall. Preferably the perforations of the cylindrical wall comprise holes having a diameter of no greater than 25 mm, more preferably from about 2 to 25 mm, especially from about 2 to about 10 mm, even more especially from about 4 to about 10 mm, and yet more especially from about 5 to about 8 mm. Optionally said perforations can comprise holes having a diameter of from about 2 to 3 mm.
Preferably up to 60% of the surface area of the cylindrical side wall of the drum 12 comprises perforations. More preferably no more than 50%, even more preferably no more than 40% of the surface area of the side wall comprises perforations. Preferably at least 5%, more preferably at least 10% and especially at least 20% of the surface area of the cylindrical side wall of the drum 12 comprises perforations.
The solid particulate material may be discharged from the drum 12 through said perforations or can be transported from the drum 12 by other means. Generally the perforations in the drum 12 can be sized at around 2-3 times the average particle diameter of a particle comprised in said solid particulate material which, typically, results in perforations having a diameter of no greater than about 10.0 mm.
Optionally said perforations of the drum 12 permit the ingress and egress of fluids and fine particulate materials of lesser diameter than the holes, but are adapted so as to prevent the egress of said solid particulate material employed by the apparatus of the invention.
Preferably said perforations of the drum 12 permit the ingress and egress of fluids and said solid particulate material employed by the apparatus of the invention.
Rotation of said drum 12 can be effected by use of drive means, which typically can comprise electrical drive means, in the form of an electric motor. Operation of said drive means can be effected by control means which may be operated by a user.
Preferably the apparatus of the present invention is a cleaning apparatus such as a washing machine (e.g. a commercial washing machine or a domestic washing machine). The apparatus of the present invention can be a commercial washing machine. The drum 12 can be of the size which is to be found in most commercially available washing machines and tumble driers, and can have a capacity in the region of 10 to 7000 litres. A typical capacity for a domestic washing machine would be in the region of 30 to 150 litres whilst, for an industrial washer-extractor, capacities anywhere in the range of from 150 to 7000 litres are possible. A typical size in this range is that which is suitable for a 50 kg washload, wherein the drum has a volume of 450 to 650 litres and, in such cases, said drum 12 would generally comprise a cylinder with a diameter in the region of 75 to 120 cm, preferably from 90 to 110 cm, and a length of between 40 and 100 cm, preferably between 60 and 90 cm.
The apparatus of the present invention can be a domestic washing machine such as a machine configured for location in a private dwelling such as a house or apartment. Typically said domestic washing machine can comprise a drum 12 having a capacity of from 30 to 150 litres. The drum 12 can have a capacity of from 50 to 150 litres. Generally the drum 12 of said domestic washing machine will be suitable for a 5 to 15 kg washload. The drum 12 can typically comprise a cylinder with a diameter in the region of 40 to 60 cm and a length in the region of 25 cm to 60 cm. The drum can typically have 20 to 25 litres of volume per kg of washload to be cleaned.
The apparatus 100 according to the invention can comprise at least one delivery means 13. The delivery means 13 can provide for the entry of wash liquor constituents directly (that is, otherwise than by way of the sump 22 and pumping device 50 as described herein below). Optionally, the cleaning apparatus can comprise a multiplicity of delivery means. Suitable delivery means can include one or more spraying means such as spray nozzle. The delivery means 13 can deliver, for example, water, one or more cleaning agents or water in combination with said one or more cleaning agents. The delivery means of the apparatus 100 can be adapted to first add water to moisten the substrate(s) before commencing the wash cycle. The delivery means 13 can be adapted to add one or more cleaning agents during the wash cycle. The delivery means can be mounted on a portion of the door 18.
The particles of the solid particulate material can be efficiently circulated within the drum to promote effective treatment. The drum 12 can therefore include circulation means which can promote circulation of the substrate being cleaned and the solid particulate material. Thus, the inner surface of the cylindrical side wall of said drum 12 can comprise a multiplicity of spaced apart elongated protrusions affixed essentially perpendicularly to said inner surface. Typically the protrusions are aligned with the axis of rotation of drum 12. Said protrusions can additionally comprise air amplifiers which are typically driven pneumatically and are adapted so as to promote circulation of a current of air within said cage. Typically said apparatus 100 can comprise from 3 to 10, preferably 4, of said protrusions, which are commonly referred to as lifters.
The lifters can function as collecting and transferring devices for gathering solid particulate material and transferring it to the exterior of the drum 12. In particular, the lifters can collect the solid particulate material and transfer it to the collecting volume. Referring by way of example to
The lifters 68 can comprise a first aperture allowing ingress of solid particulate material into a capturing compartment and a second aperture allowing transfer of said solid particulate material to the exterior of drum 12. The dimensions of the apertures can be selected in line with the dimensions of the solid particulate material, so as to allow efficient ingress and transfer thereof.
As noted above, the apparatus 100 further comprises a collecting volume in which the solid particulate material (or portions thereof) may accumulate at times during the treatment/cleaning cycle using the apparatus 100. Preferably, the collecting volume is in the form of a sump 22. The solid particulate material may accumulate in the sump 22 after leaving the drum 12. In addition, the sump 22 can further contain water and/or one or more cleaning agents (i.e. wash liquor).
The sump 22 may be provided in conjunction with the tub 14. Preferably, the sump 22 may be located below the drum 12 so that wash liquor may drain naturally into the sump 22, that is, without the intervention of any pump or the like. Similarly it is preferred that the sump 22 is located below the drum 12 so that the solid particulate material which exits the drum 12 during use of the apparatus may pass into the sump 22 under the influence of gravity. In preferred forms of the apparatus 100, the sump 22 is arranged directly beneath the drum 12. The sump 22 may be formed integrally with the tub 14. Thus the tub 14, the sump 22 and the door 18 (in its closed position) form a closed space within which the solid particulate material and wash liquor may be confined during the treatment process.
The sump 22 can extend within a lower portion of the tub 14. As shown in
Typically, the sump 22 is enlarged in comparison to those found in conventional washing machines. Thus, the distance between the drum 12 and the floor 22e of the sump 22 can, for example, be at least 10 cm. Advantageously, this can allow for a greater capacity to retain the solid particulate material for use in the apparatus.
A circulation path is provided for the transfer of solid particulate material in combination with a carrier fluid, which is typically wash liquor, from the sump 22 to the drum 12. The circulation pathway may include a pumping device 50 and appropriate pipework or tubing 40 for conveying the solid particulate material and the carrier fluid.
Pumping device 50 is shown schematically in
In use of the apparatus 100, solid particulate material falls to inclined floor 22e. The inclined construction of floor 22e directs the solid particulate material towards the lowest part of the sump 22, that is, in the region proximate the pumping device 50.
Generally during a washing procedure, some wash liquor is also present in the sump 22. The amount of wash liquor (and hence the relative amounts of wash liquor and solid particulate material) may be regulated during the course of the wash cycle. In some circumstances, such as the very end or the beginning of a cleaning procedure, wash liquor may be substantially absent from the sump 22.
During a substrate treatment procedure using the apparatus 100, solid particulate material is transferred from the sump 22 to the drum 12. To this end the pumping device 50 and a circulation path (via arrow L) are provided. For such transfer of the solid particulate material, the solid particulate material is in mixture with the carrier fluid, which is preferably the wash liquor. Thus, pumping device 50 pumps the mixture of wash liquor and solid particulate material from the sump 22 to the drum 12. The solid particulate material may be pumped by the pumping means 50 into the drum 12 either continuously or at intervals, depending on factors such as the substrate being cleaned and the particular treatment process or cleaning cycle which a user may select.
The invention disclosed herein preferably relates to an apparatus comprising a separating device positioned in the circulation path that conveys the solid particulate material in order to intercept and/or capture foreign objects that have entered the drum with the substrates in the washload and passed through the perforated cylindrical wall.
As used herein, the term “intercept” preferably means foreign objects in the circulation path are blocked by the separating device which serves as barrier to shield a subsequent or following portion of the collecting volume from the foreign objects. As used herein, the term “captured” preferably means foreign objects can be retained in an essentially fixed position once extracted from the circulation path by the separating device.
The separating device 200 is shown schematically in
The separating device illustrated in
The solid particle transfer portion thus defines a plurality of transfer flow paths for solid particles. Typically, said plurality of transfer flow paths are arranged in a linear array 208a, 208b. The solid particle transfer portions 206a, 206b are each connected to a periphery of the sloping body portion 202. Each transfer flow path can thus be arranged at or proximate a lower marginal edge portion of the sloping surface of the body portion 202.
In operation, the sloping body portion 202 of the separating device 200 and the particle directing element(s) direct solid particles exiting the drum 12 via void 15 into the solid particle transfer portion(s). Thus, as shown in
Although the sloping body portion 202 in
The top surface 200A can be adapted to further facilitate the transport of solid particles to the solid particle transfer portions 206a, 206b. The upper surface 201A (particularly the sloping body portion 202) can include formations, ridges or grooves formed therein to promote the flow of solid particles along its surface. One or more components of the separating device 200 including said upper surface 201A can comprise stainless steel wherein the grain of the steel runs in the direction of the particle transfer portions 206a, 206b in order to facilitate improved transport of said solid particles. Alternatively, or in addition, the upper surface 201A can be modified, treated or coated in order to increase its smoothness. The upper surface 201A can include a hydrophobic coating.
As shown in
An angle (α) defines the angle of entry of the solid particles to the particle transfer portion(s) (i.e. via inlet opening 210A). In the illustrated separating device, the angle (α) equates to the angle of inclination of the body portion 202b with respect to the horizontal. The angle (α) can be selected to maximise the efficiency of flow through the separating device 200. Generally, in order of increasing preference, the angle (α) is at least 5°, 10°, 20°, 25°, 30° or 35°. Generally, in order of increasing preference, the angle (α) is no more than 80°, 70° 60° or 50°. In one preferred arrangement, the angle (α) is from about 5° to about 60°, more preferably from about 10° to about 45° and most preferably from about 15° to about 30°. Preferably the angle (α) is about 20°. In a further preferred arrangement, the angle (α) is from about 25° to about 60°, preferably from about 30° to 50°, more preferably about 30° to about 45° even more preferably from about 35° to about 40°. It will be appreciated from a comparison of
The separating device of the invention can comprise one or more internal surfaces between the inlet opening 210A and the outlet opening 210B configured to cause a change in direction of the flow of solid particles within the transfer flow path. Specifically, solid particles enter the particle transfer portion 206b and transfer flow path along a first direction (i.e. B2) and leave along a second direction (i.e. C2) that is different to the first direction. The difference between the first direction and the second direction can be represented by an angle (β). Preferably, the angle (β) is from about 120° to about 10°, more preferably from about 100° to about 15° and most preferably from about 80° to about 20°. Preferably the angle (β) is about 50°.
Preferably the angle (α) is about 20° and the angle (β) is about 50°.
The distance between the marginal edge of the sloping surface 202ba and the closure wall 205b at the entry point 210A as represented by 210Ad can be in the region of 2.0 mm to 30 mm. Preferably, distance 210Ad is from 2.0 mm to 20 mm. Preferably the distance 210Ad is about 12 mm.
The largest dimension about a vertical axis within the transfer flow path (and located between a terminal portion of the lower marginal edge 202ba and an opposed portion of the wall member 205b as represented by 211d in
The distance across the outlet opening 210B as represented by 210Bd in
The skilled person will however recognise that the dimensions of the transfer flow path as represented by 210Ad, 211d and 210Bd can be selected and modified in accordance with the maximum dimension of the solid particles utilised in the apparatus of the invention. Furthermore, the dimensions of the transfer flow path can further be adjusted and tailored according to the dimensions of the foreign objects to be intercepted and/or captured.
Preferably the distance 210Ad is about 12 mm, the distance 211d is about 13 mm and the distance 210Bd is about 12 mm. Preferably the curved wall member 205b has a radius of curvature of about 11.5 mm.
The spacing between opposed side walls 209A, 209B is typically in the region of 5 mm to 30 mm. Preferably, the spacing between opposed side walls 209A, 209B is 15 mm to 30 mm. Typically the spacing between opposed side walls 209A, 209B is about 24 mm.
As for the dimensions of the transfer flow path within the solid particle transfer portion described above, the spacing between the opposed side walls can be modified in accordance with the maximum dimension of the solid particles utilised in the apparatus of the invention and/or according to the dimensions of the foreign objects to be intercepted and/or captured.
The transfer flow path as provided within the solid particle transfer portion(s) of the separating device 200 of the invention is further configured such that although the passage of said solid particles employed by the apparatus is permitted, the passage of specified foreign objects is prevented. Referring again to
Preferably foreign objects that can be intercepted and/or captured by the separating device of the invention are elongated. Thus, said foreign objects have a length dimension and a width dimension wherein said length dimension is greater than said width dimension. Preferably, said length dimension is at least two times greater than said width dimension. Most preferably, said length dimension is at least four times greater than said width dimension.
Examples of foreign objects to be intercepted and/or captured by the invention include, but are not limited to, nails, screws, nuts, paper clips, toothpicks, hypodermic needles, pencils, pens, keys, cotton buds, needles, small hand tools or parts thereof (e.g. screwdrivers and drill bits), pins, hairpins, grips cutlery (such as knives, forks (e.g. oyster forks) and spoons) and the like.
The separating device within the apparatus of the invention thus addresses the problem whereby owing to health and safety considerations in certain industrial workplaces, users are prevented from inspecting the laundry for foreign objects. Nails, screws and the like that remain in the pockets of garments and which can pass through the perforations in the drum, are thus intercepted and/or caught by the separating device before they can enter the sump and potentially damage the pumping device and/or block the circulation path.
The aforementioned predetermined length of the maximum dimension of the smallest foreign object which the separating device is configured to intercept and/or capture can be at least 30 mm. Fine particulate material and any other matter smaller than said predetermined length, along with the solid particles employed in the apparatus of the invention, can pass through the solid particle transfer portion(s) of the separating device 200 and into a lower portion of the sump 22.
Depending on the size and orientation of the foreign object(s) that become lodged in the transfer flow path, solid particles may still be able to pass through the separating device 200 and into a lower portion of the sump 22 despite the obstruction. However, should a given transfer flow path become blocked, the arrangement of the solid particle transfer portions having a plurality of said transfer flow paths defined therein advantageously ensures a multitude of alternative routes are provided for the solid particles to pass through the separating device 200. Furthermore, such an arrangement enables a number of elongated foreign objects to be intercepted and/or captured by the separated device 200.
A further separating device 200 of the invention is shown in
A connecting member 304b or web links first solid particle transfer portion 206b to second solid transfer portion 306b on one side of the separating device 200. The connecting member 304b can also function as a solid particle directing element to deflect particles towards the sloping surface 202b and into the first solid particle transfer portion 206b. Similar to the solid particle transfer portion 206b described in
The dimensions for the respective components of the flow path for the solid particle transfer portion 306b as illustrated in
Advantageously, the separating device illustrated and described with respect to
A further separating device 200 of the invention is shown in
The solid particle transfer portion 406b comprises a solid particle directing element 408b and a closure wall 405b. A sloping surface is provided by the sloping floor surface 402ba. The sloping floor 402ba of solid particle transfer portion 406b can extend laterally from an external surface of closure wall 205b of the solid particle transfer portion 206b. Particularly, the sloping floor 402ba extends from an upper portion of the external surface of closure wall 205b. A transfer flow path is defined between sloping floor surface 402ba and closure wall 405b. Solid particles enter the transfer flow path via inlet opening 410A in the general direction of arrow G2. The solid particles then follow a substantially curved path before leaving via outlet opening 410B in the general direction of arrow H2. When solid particles leave via outlet opening 410B, they can contact a lower portion of the external surface of closure wall 205b before falling beyond the separating device 200 to the floor of the sump 22.
Advantageously, the structural arrangement of the respective solid particle transfer portions in the separating device illustrated in
The dimensions for the respective components of the flow path for the solid particle transfer portion 406b as illustrated in
An alternative separation device denoted as 200B is shown in
In operation, the sloping body portion 202 of the separating device 200B and the particle directing element direct solid particles exiting the drum 12 via void 15 into the solid particle transfer portion(s). Thus, as shown in
The respective opposed side walls 209 upstanding from a lower marginal edge portion of the sloping surface 202 are non-planar. The respective side walls 209, extend upwardly from the sloping surface 202 to respective top marginal edges. Closure wall 215Ba extends above the sloping surface 202 between the respective top marginal edges of the opposed side walls 209.
In some preferred configurations, each side wall 209 comprises first and second planar side wall panels 209Ba, 209Bb, extending from a common edge in a “v” or chevron configuration.
As shown in
The inlet opening 210BA of the transfer flow path for the separating device 200B can thus be defined by an upper side of the sloping surface 201A, an underside of the closure wall 215Ba and respective upstream edges of the side walls 209. The outlet opening 210BB of the transfer flow path for the separating device 200B can be defined by an the upper side of the sloping surface 201A an underside of the closure wall 215Ba and respective downstream edges of the side walls 209. The “upstream” and “downstream” edges refer to the flow direction of the multiplicity of solid particles through the transfer flow path.
The distance between the first planar side wall panel 209Ba of a first side wall 209 and the first planar side wall panel 209Ca of an adjacent side wall 209 at the inlet opening 210BA as represented by 210BAd can be in the region of 2.0 mm to 30 mm. Preferably, distance 210BAd is from 2.0 mm to 20 mm. Preferably the distance 210Bad is about 10 mm.
The distance between the first planar side wall panel 209Ba and second planar side wall panel 209Bb as represented by 209Bd is about 30 mm. The thickness of the side walls 209 and thus the side wall panels (209Ba, 209Bb, 209Ca, 209Cb) is about 0.90 mm.
The distance between the second planar side wall panel 209Bb of a first side wall 209 and the second planar side wall panel 209Cb of an adjacent side wall 209 at the outlet opening 210BB as represented by 210BBd can be in the region of 2.0 mm to 30 mm. Preferably, distance 210BBd is from 2.0 mm to 20 mm. Preferably the distance 210BBd is about 10 mm.
As for the transfer flow path of the previously described separating device 200, the skilled person will however recognise that the spacing between the side walls 209 and their panels plus the dimensions of the transfer flow path can be selected and modified in accordance with the maximum dimension of the solid particles utilised in the apparatus of the invention. Furthermore, the spacing between the side walls, planar side wall panels plus the dimensions of the transfer flow path can further be adjusted and tailored according to the dimensions of the foreign objects to be intercepted and/or captured.
Referring now to
The geometry and dimension of the side walls 209 for the separation device 200B are particularly adept at retaining said one or more elongated foreign objects in an essentially fixed position. The use of side walls with this type of configuration can reduce the likelihood that the elongated foreign objects will become dislodged from the solid particle transfer portion once they have been captured.
As previously described above, solid particles exiting through the perforations of the drum 12 proceed downwardly along a path through the void 15 before contacting one or more of the upper surfaces of the separating device and exit the separating device through the openings of the solid particle transfer portion(s). It will also be understood that any carrier fluid (e.g. wash liquor) present with the solid particles in the drum 12 can also proceed along a similar route. After the solid particles (together with any carrier fluid) have exited the separating device they accumulate in the sump 22 until the solid particulate material is transported by the pumping device 50 along the circulation path denoted by the arrow L.
The separating device 200 of the invention may be arranged to enhance the distribution of the solid particulate material as it accumulates in the sump 22. Thus, in operation, the separating device 200 can be arranged such that a first end 200a is in abutment with the sump front wall 22a and a second end 200b abuts the rear wall 22b. As illustrated in
As illustrated in
Thus, the separating device 200 can be retrofitted to existing machines that are adapted to treat substrates with a solid particulate material (so-called “bead cleaning machines”) following only minor modifications. Examples of suitable apparatus for which the separating device can be installed include the cleaning system disclosed in WO2011/098815. To accommodate the separating device 200, the machine can, for example, simply be adapted to include an aperture in its external housing and formations or shelving incorporated in the sidewalls of the sump.
The separating device present in the apparatus of the invention preferably comprises materials that exhibit some resistance to corrosion and particularly comprises materials that exhibit resistance to the corroding effects of any ingredients or additives present in the carrier fluid which is preferably wash liquor. Thus preferably the separating device comprises corrosion resistant metals and/or metal alloys. Preferably the separating device comprises stainless steel. Alternatively the separating device can comprise a plastic or polymeric material. Optionally the separating device can be coated with a polymeric material such as polytetrafluoroethylene (PTFE).
The treatment apparatus 100 of the present invention is designed to operate in conjunction with soiled substrates and cleaning media comprising a solid particulate material (also referred to as a multiplicity of solid particles), which can be in the form of a multiplicity of polymeric particles and/or a multiplicity of non-polymeric particles. Thus, preferably, the treatment performed by the apparatus of the invention is a cleaning treatment.
The apparatus 100 according to the invention is principally designed for use in the cleaning of substrates, especially those comprising a textile fibre including for example garments, linens, napery and the like, and has been shown to be particularly successful in achieving efficient cleaning of textile fibres which may, for example, comprise either natural fibres, such as cotton, wool, silk or man-made and synthetic textile fibres, for example nylon 6,6, polyester, cellulose acetate, or fibre blends thereof.
The solid particulate material for use in the apparatus and method of the invention can comprise a multiplicity of polymeric particles and/or a multiplicity of non-polymeric particles. Preferably, the solid particulate material comprises a multiplicity of polymeric particles. Alternatively, the solid particulate material can comprise a mixture of polymeric particles and non-polymeric particles. The solid particulate material can comprise a multiplicity of non-polymeric particles. Thus the solid particulate material can comprise exclusively polymeric particles, exclusively non-polymeric particles or mixtures of polymeric and non-polymeric particles.
The polymeric particles or non-polymeric particles can be of such a shape and size as to allow for good flowability and intimate contact with the substrate and particularly with textile fibre. A variety of shapes of particles can be used, such as cylindrical, spherical or cuboid; appropriate cross-sectional shapes can be employed including, for example, annular ring, dog-bone and circular. Most preferably, however, said particles can comprise cylindrical, ellipsoidal, spheroidal or spherical beads.
The polymeric particles or non-polymeric particles can have smooth or irregular surface structures and can be of solid, porous or hollow structure or construction.
The polymeric particles can be of such a size as to have an average mass of about 1 mg to 1000 mg, or of about 1 mg to about 700 mg, or of about 1 mg to about 500 mg or of about 1 mg to about 300 mg, of about 1 mg to 150 mg, of about 1 mg to about 70 mg or of about 1 mg to about 50 mg or of about 1 mg to about 35 mg or of about 10 mg to about 30 mg. The polymeric or non-polymeric particles can be of such a size as to have an average mass of about 12 mg to about 25 mg.
The non-polymeric particles can be of such a size as to have an average mass of about 1 mg to about 1 g or of about 1 mg to about 700 mg, or of about 1 mg to 500 mg, or of about 1 mg to about 300 mg, or of about 10 mg to about 100 mg or of about 25 mg to about 100 mg.
The polymeric or non-polymeric particles can have a surface area of 10 mm2 to 500 mm2, 10 mm2 to 300 mm2, 10 mm2 to 120 mm2, 15 mm2 to 50 mm2 or of 20 mm2 to 40 mm2.
Preferably, the polymeric particles have an average density in the range of from about 0.5 to about 2.5 g/cm3, more preferably in the range of from about 0.55 to about 2.0 g/cm3 and especially in the range of from about 0.6 to about 1.9 g/cm3.
The non-polymeric particles typically have an average density greater than the polymeric particles. Thus, the non-polymeric particles preferably have an average density in the range of about 3.5 to about 12.0 g/cm3, more preferably in the range of about 5.0 to about 10.0 g/cm3, especially in the range of about 6.0 to about 9.0 g/cm3.
Preferably, the average volume of the polymeric and non-polymeric particles is in the range of 5 to 800 mm3, more preferably 5 to 500 mm3 and even more preferably from 5 to 275 mm3. The average volume of the polymeric and non-polymeric particles can be in the range of 8 to 140 mm3 or in the range of 10 to 120 mm3.
Preferably the polymeric or non-polymeric particles are substantially cylindrical, substantially ellipsoidal or substantially spherical in shape.
The substantially cylindrical particles can be of oval cross section. In such cases, the major cross section axis length, a, can be in the region of from 2.0 to 6.0 mm, in the region of from 2.2 to 5.0 mm or in the region of from 2.4 mm to 4.5 mm. The minor cross section axis length, b, can be in the region of from 1.3 to 5.0 mm, in the region of from 1.5 to 4.0 mm or in the region of from 1.7 mm to 3.5 mm. For an oval cross-section, a>b.
Typically, the length of the cylindrical particles, h, can be in the range of from about 1.5 mm to about 6 mm, from about 1.7 mm to about 5.0 mm or from about 2.0 mm to about 4.5 mm. The ratio h/b can typically be in the range of from about 0.5 to about 10.
The cylindrical particles can be of circular cross section. The typical cross section diameter, dc, can be in the region of from about 1.3 to about 6.0 mm, in the region of from about 1.5 to about 5.0 mm or in the region of from about 1.7 mm to about 4.5 mm. The length of such particles, hc, can be in the range of from about 1.5 mm to about 6 mm, from about 1.7 mm to about 5.0 mm or from about 2.0 mm to about 4.5 mm. The ratio hc/dc can typically be in the range of from about 0.5 to about 10.
The particles can be generally spherical in shape (but not a perfect sphere) having a particle diameter, ds, in the region of from 2.0 to 8.0 mm, more preferably from 2.2 to 5.5 mm and even more preferably in the region of from about 2.4 mm to about 5.0 mm.
The particles can be substantially spherical in shape having a particle diameter, dps, in the region of from 2.0 to 8.0 mm, more preferably in the region of from 3.0 to 7.0 mm and especially in the region of from about 4.0 mm to about 6.5 mm.
Preferably the polymeric particles comprise polyalkenes such as polyethylene and polypropylene, polyamides, polyesters, polysiloxanes or polyurethanes. Furthermore, said polymers can be linear, branched or crosslinked. Preferably, said polymeric particles comprise polyamide or polyester particles, particularly particles of nylon, polyethylene terephthalate or polybutylene terephthalate, typically in the form of beads. Said polyamides and polyesters are found to be particularly effective for aqueous stain/soil removal, whilst polyalkenes are especially useful for the removal of oil-based stains.
Various nylon homo- or co-polymers can be used including, but not limited to, Nylon 6 and Nylon 6,6. The nylon can comprise Nylon 6,6 copolymer, typically having a molecular weight in the region of from about 5000 to about 30000 Daltons, such as from about 10000 to about 20000 Daltons, or such as from about 15000 to about 16000 Daltons. Useful polyesters can have a molecular weight corresponding to an intrinsic viscosity measurement in the range of from about 0.3 to about 1.5 dl/g, as measured by a solution technique such as ASTM D-4603.
The polymeric particles can comprise foamed polymers. Alternatively the polymeric particles can comprise unfoamed polymers.
Optionally, copolymers of the above polymeric materials may be employed for the purposes of the invention. Specifically, the properties of the polymeric materials can be tailored to specific requirements by the inclusion of monomeric units which confer particular properties on the copolymer. Thus, the copolymers can be adapted to attract particular staining materials by including monomer units in the polymer chain which, inter alia, are ionically charged, or include polar moieties or unsaturated organic groups. Examples of such groups can include, for example, acid or amino groups, or salts thereof, or pendant alkenyl groups.
The non-polymeric particles can comprise particles of glass, silica, stone, wood, or any of a variety of metals or ceramic materials. Suitable metals include, but are not limited to, zinc, titanium, chromium, manganese, iron, cobalt, nickel, copper, tungsten, aluminium, tin and alloys thereof. Suitable ceramics include, but are not limited to, alumina, zirconia, tungsten carbide, silicon carbide and silicon nitride. In general, though, polymeric particles are preferred for textile cleaning using the apparatus of the invention.
The treatment apparatus of the invention thus provides a means for cleaning a soiled substrate comprising treating the substrate with a formulation comprising said solid particulate material and wash liquor.
In order to provide additional lubrication to the treatment apparatus 100 and thereby improve the transport properties within the system, wash liquor, which can comprise or be water, is added. Thus, more efficient transfer of the cleaning material to the substrate is facilitated, and removal of soiling and stains from the substrate occurs more readily. The solid particulate material can thus elicit a cleaning effect on the substrate and water can simply aid the transport of said solid particulate material. Optionally, the soiled substrate may be moistened by wetting with water (e.g. mains or tap water) prior to loading into the cleaning apparatus of the invention. Wetting of the substrate within the apparatus of the invention is preferable. In any event, water can be added to the drum 12 of the invention such that the washing treatment is carried out so as to achieve a wash water or wash liquor to substrate ratio in the drum 12 which, preferably is between 5:1 and 0.1:1 w/w, more preferably between 2.5:1 and 0.1:1 w/w and especially between 2.0:1 and 0.8:1 w/w. By means of example, particularly favourable results have been achieved at ratios such as 1.75:1, 1.5:1, 1.2:1 and 1.1:1. Most conveniently, the required amount of water can be introduced into the drum 12 of the apparatus according to the invention after loading of the soiled substrate into said drum. The wash liquor to substrate ratio can however be maintained within predetermined limits throughout the wash cycle. The predetermined limits may be different in different stages of the wash cycle.
Whilst, the treatment apparatus of the invention envisages the cleaning of a soiled substrate by the treatment of a moistened substrate only with solid particulate material (i.e. in the absence of any further additives), optionally at least one cleaning agent may additionally be included. The at least one cleaning agent can include at least one detergent composition. Said at least one cleaning agent can be mixed with said solid particulate material, for example as component of the wash liquor. Said particles comprised in said solid particulate material can be coated with at least one cleaning agent.
The principal components of the detergent composition can comprise cleaning components and post-treatment components. The cleaning components can comprise surfactants, enzymes and bleach, whilst the post-treatment components can include, for example, anti-redeposition additives, perfumes and optical brighteners.
However, the wash liquor can further optionally include one or more other additives such as, for example builders, chelating agents, dye transfer inhibiting agents, dispersants, enzyme stabilizers, catalytic materials, bleach activators, polymeric dispersing agents, clay soil removal agents, suds suppressors, dyes, structure elasticizing agents, fabric softeners, starches, carriers, hydrotropes, processing aids and/or pigments.
The composition of the wash liquor may depend at any given time on the point which has been reached in the cleaning cycle for the soiled substrate using the apparatus of the invention. Thus, for example, at the start of the cleaning cycle, the wash liquor may be water. At a later point in the cleaning cycle the wash liquor may include detergent and/or one of more of the above mentioned additives. During a cleaning stage of the cleaning cycle, the wash liquor may include suspended soil removed from the substrate.
Preferably the ratio of solid particulate material to substrate is generally in the range of from about 0.1:1 to about 30:1 w/w, more preferably in the range of from about 0.1:1 to about 20:1 w/w, especially in the range of from about 0.1:1 to about 15:1 w/w, more especially in the range of from about 0.1:1 to about 10:1 w/w, even more especially in the range of from 0.5:1 to about 5:1 w/w, yet more especially in the range of about 1:1 and about 3:1 w/w and, most especially, around 2:1 w/w. Thus, for example, for the cleaning of about 5 g of fabric, about 10 g of polymeric or non-polymeric particles could be in the invention.
The apparatus of the present invention can be used for either small or large scale batchwise processes and finds application in both domestic and industrial cleaning processes. The present invention can be applied to domestic washing machines and processes.
In a typical wash cycle using the treatment apparatus 100 of the invention, soiled garments are first placed into the drum 12. Then, an appropriate amount of wash liquor (water, together with any additional cleaning agent), can be added to said drum 12 such as via the delivery means 13. The water can be pre-mixed with the cleaning agent prior to its introduction into the drum 12. Typically, water can be added first in order to suitably wet or moisten the substrate before further introducing any cleaning agent. Optionally the water and the cleaning agent can be heated. Following the introduction of water and any optional cleaning agents, the treatment/cleaning cycle can commence by rotation of the drum 12. The solid particulate material and (further) wash liquor residing in the sump 22, which optionally can be heated to a desired temperature, is then pumped by pumping device 50 onto a washload contained in the drum 12.
During the course of agitation by rotation of the drum 12 wash liquor (including any cleaning agents) and a quantity of the solid particulate material (i.e. the cleaning media) exit the drum 12 and pass into the sump 22. Optionally, lifters 68 disposed on the inner circumferential surface of the drum 12 can collect the solid particulate material as the drum rotates and transfer the solid particulate material to a region at or proximate the void 15. The sloping floor 22e directs the solid particulate material and wash liquor towards the lowest region of the sump 22. From the sump 22, the pumping device 50 again pumps wash liquor in combination with the solid particulate material via ducting 40 into the drum 12 as required during the wash cycle. Furthermore, solid particulate material used in the cleaning operation which exits the drum 12 and returns to the sump 22 can be reintroduced into the drum 12 and can therefore be re-used in either a single wash cycle or subsequent wash cycles.
The treatment apparatus 100 can perform a wash cycle in a similar manner to a standard washing machine with the drum 12 typically rotating at between about 30 and about 40 rpm for several revolutions in one direction, then rotating a similar number of rotations in the opposite direction. This sequence can be repeated for up to about 60 minutes, by way of example. During this period, solid particulate material can be introduced and reintroduced to the drum 12 from the sump 22 in the manner as described above.
As previously noted, the apparatus of the invention can find particular application in the cleaning of textile fibres. The conditions employed in such a cleaning system do, however, allow the use of significantly reduced temperatures from those which typically apply to the conventional wet cleaning of textile fabrics and, as a consequence, offer significant environmental and economic benefits. Thus, typical procedures and conditions for the wash cycle require that fabrics are generally treated with the apparatus of the invention at, for example, temperatures of between 5 and 95° C. for a duration of between about 5 and 120 minutes in a substantially sealed system. Thereafter, additional time is required for the completion of the rinsing and any further stages of the overall process, so that the total duration of the entire cycle is typically in the region of about 1 hour. The operating temperatures for the apparatus of the invention can be in the range of from about 10 to about 60° C. or from about 15 to about 40° C.
The cleaning performance attained when cleaning with the apparatus of the invention are very much in line with those observed when carrying out conventional wet (or dry) cleaning procedures with textile fabrics. The extent of cleaning and stain removal achieved with fabrics treated by the apparatus of the invention is seen to be very good, with particularly outstanding results being achieved in respect of hydrophobic stains and aqueous stains and soiling, which are often difficult to remove. The energy requirement, the total volume of water used, and the detergent consumption when using the apparatus of the invention are all significantly lower than those levels associated with the use of conventional aqueous washing procedures, again offering significant advantages in terms of cost and environmental benefits.
It has been found that the apparatus according to the present invention allows a user to load the machine with substrates which inadvertently contain foreign bodies such as nails, screws, bolts, pins, oyster forks etc. but without adversely affecting performance of the apparatus. The present invention was found to permit the apparatus to continue to operate even when several foreign bodies accumulated in the apparatus. The separating device was found to trap the foreign objects without inhibiting the flow of the solid particulate material or the wash liquor. Without the separating apparatus foreign objects, such as those referred to above, were found to degrade system performance and often caused a blockage of the pump which required an engineer to unblock. In one particular trial of the apparatus according to the present invention the apparatus was operated for over 100 wash cycles with substrates often containing foreign bodies without any blockage and without any appreciable adverse effects on washing performance. The present inventors consider that blockage in less than 10 cycles would be highly probably using an apparatus as described in e.g. WO2011/098815. Thus the present invention outperforms the known prior art by a substantial margin.
Throughout the description and claims of this specification, the words “comprise” and “contain” and variations of them mean “including but not limited to”, and they are not intended to (and do not) exclude other moieties, additives, components, integers or steps. Throughout the description and claims of this specification, the singular encompasses the plural unless the context otherwise requires. In particular, where the indefinite article is used, the specification is to be understood as contemplating plurality as well as singularity, unless the context requires otherwise.
Features, integers, characteristics, compounds, chemical moieties or groups described in conjunction with a particular aspect, embodiment or example of the invention are to be understood to be applicable to any other aspect, embodiment or example described herein unless incompatible therewith. All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive. The invention is not restricted to the details of any foregoing embodiments. The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.
The reader's attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.
| Number | Date | Country | Kind |
|---|---|---|---|
| 1416718.3 | Sep 2014 | GB | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/GB2015/052737 | 9/22/2015 | WO | 00 |
