US20150252511A1

US20150252511A1 - Cleaning apparatus and method

Info

Publication number: US20150252511A1
Application number: US14/427,046
Authority: US
Inventors: Steven Marlon Roberts; Venkata Satyanarayana Kancharla; Charles Andrew Maltby
Original assignee: Xeros Ltd
Current assignee: Xeros Ltd
Priority date: 2012-09-10
Filing date: 2013-09-05
Publication date: 2015-09-10
Also published as: CN104781463A; WO2014037729A1; MX2015003051A; TW201418542A; TWI640670B; EP2904141A1; KR20150053792A; HK1210814A1; CA2884293A1; GB201216101D0; CN104781463B

Abstract

The invention provides an apparatus and method for use in the cleaning of soiled substrates, the apparatus comprising housing means comprising: (a) a stationary member; (b) a rotatably mounted cylindrical cage; and (c) access means, wherein said stationary member comprises an annular planar member which is of greater internal diameter than said access means and is located adjacent said rotatably mounted cylindrical cage and said stationary member comprises a multiplicity of delivery means which are mounted thereon and a multiplicity of orifices which are respectively operably connected to said multiplicity of delivery means, wherein said multiplicity of delivery means is adapted to facilitate the delivery of materials into said rotatably mounted cylindrical cage. The method involves cleaning the soiled substrate by treatment of the moistened substrate with a formulation comprising solid particulate cleaning material and wash water, the method being carried out using the apparatus of the invention. The apparatus and method find particular application in the cleaning of textile fabrics.

Description

FIELD OF THE INVENTION

The present invention relates to the aqueous cleaning of substrates using a cleaning system which requires the use of only limited quantities of energy, water and detergent. Most particularly, the invention is concerned with the cleaning of textile fibres and fabrics and other substrates by means of such a system, and provides an apparatus adapted for use in this context which provides significant design advantages over the systems of the prior art.

BACKGROUND TO THE INVENTION

Aqueous cleaning processes are a mainstay of both domestic and industrial textile fabric washing. On the assumption that the desired level of cleaning is achieved, the efficacy of such 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.
Such washing processes involve aqueous submersion of fabrics followed by soil removal, aqueous soil suspension, 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. The 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.
Various different approaches to the development of new cleaning technologies have been reported in the prior art, including methods which rely on electrolytic cleaning or plasma cleaning, in addition to approaches which are based on ozone technology, ultrasonic technology or steam technology. Thus, for example, WO-A-2009/021919 teaches a fabric cleaning and disinfection process which utilises UV-produced ozone along with plasma. An alternative technology involves cold water washing in the presence of specified enzymes, whilst a further approach which is particularly favoured relies on air-wash technology and, for example, is disclosed in US-A-2009/0090138. In addition, various carbon dioxide cleaning technologies have been developed, such as the methods using ester additives and dense phase gas treatments which are described in U.S. Pat. No. 7,481,893 and US-A-2008/0223406, although such methods generally find greater applicability in the field of dry cleaning. Many of these technologies are, however, technically very complex.
In the light of the challenges which are associated with aqueous washing processes, the present inventors have previously devised a new approach to the problem, which is technologically straightforward, and yet still allows the deficiencies demonstrated by the methods of the prior art to be overcome. The method which is provided eliminates the requirement for the use of large volumes of water, but is still capable of providing an efficient means of cleaning and stain removal, whilst also yielding economic and environmental benefits.
Thus, in WO-A-2007/128962 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. Preferably, the substrate is wetted so as to achieve a substrate to water ratio of between 1:0.1 to 1:5 w/w, and optionally, the formulation additionally comprises at least one cleaning material, which typically comprises a surfactant, which most preferably has detergent properties. In preferred embodiments, the substrate comprises a textile fibre and the polymeric particles may, for example, comprise particles of polyamides, polyesters, polyalkenes, polyurethanes or their copolymers, but are most preferably in the form of nylon beads.
The use of this cleaning method, however, presents a requirement for the cleaning beads to be efficiently separated from the cleaned substrate at the conclusion of the cleaning operation, and this issue was initially addressed in WO-A-2010/094959, which provides a novel design of cleaning apparatus requiring the use of two internal drums capable of independent rotation, and which finds application in both industrial and domestic cleaning processes.
With a view to providing a simpler, more economical means for addressing the problem of efficient separation of the cleaning beads from the substrate at the conclusion of the cleaning process, however, a further apparatus is disclosed in WO-A-2011/064581. The apparatus of WO-A-2011/064581, which finds application in both industrial and domestic cleaning processes, comprises a perforated drum and a removable outer drum skin which is adapted to prevent the ingress or egress of fluids and solid particulate matter from the interior of the drum. The cleaning method requires attachment of the outer skin to the drum during a first wash cycle, after which the skin is removed prior to operating a second wash cycle, following which the cleaned substrate is removed from the drum.
The apparatus and method of WO-A-2011/064581 is found to be extremely effective in successfully cleaning substrates, but the requirement for the attachment and removal of the outer skin detracts from the overall efficiency of the process and the present inventors have, therefore, sought to address this aspect of the cleaning operation and to provide a process wherein this procedural step is no longer necessary. Thus, by providing for continuous circulation of the cleaning beads during the cleaning process, it has been found possible to dispense with the requirement for the provision of an outer skin.
Thus, in WO-A-2011/098815, the present inventors 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.
The apparatus is used for the cleaning of soiled substrates by means of methods which comprise the treatment of the substrates with formulations comprising solid particulate cleaning material and wash water, the methods typically comprising the steps of:

- (a) introducing solid particulate cleaning material and water into the lower chamber of the apparatus;
- (b) agitating and heating the solid particulate cleaning material and water;
- (c) loading at least one soiled substrate into the rotatably mounted cylindrical cage via the access means;
- (d) closing the access means so as to provide a substantially sealed system;
- (e) introducing the solid particulate cleaning material and water into the rotatably mounted cylindrical cage;
- (f) operating the apparatus for a wash cycle, wherein the rotatably mounted cylindrical cage is caused to rotate and wherein fluids and solid particulate cleaning material are caused to fall through perforations in the rotatably mounted cylindrical cage into the lower chamber in a controlled manner;
- (g) operating the pumping means so as to transfer fresh solid particulate cleaning material and recycle used solid particulate cleaning material to the separating means;
- (h) operating control means so as to add the fresh and recycled solid particulate cleaning material to the rotatably mounted cylindrical cage in a controlled manner; and
- (i) continuing with steps (f), (g) and (h) as required to effect cleaning of the soiled substrate.

The requirement to introduce water and detergents into standard front loading washing machines has always presented a challenge to those in the industry, but also presents opportunities for increased efficiency of performance. Indeed, it is well understood that introducing water and detergency by spraying on to the load in a front loading washing machine provides both a means to generate cleaning performance, and also a way to reduce water consumption in the wash process. Subsequent spraying of rinse water is then a further means to reduce overall water consumption. Typically, the spray nozzle required to perform both functions is located at a point within the machine drum door that does not rotate with the movement of the wash drum, but the spray effectiveness of such an arrangement is typically limited.
Thus, in FR-A-2525645, for example, such a nozzle is fitted to the centre of the door of the machine, with the water spray therefore along the horizontal axis of the wash drum. This arrangement is somewhat inefficient, however, as it typically does not fully wet out the load in the drum as the items at the front prevent the spray from reaching those nearer the back, and those above the axis tend to receive less of the spray than those below the axis; the arrangement also inhibits easy opening and closing of the door itself. In order to address this latter problem, a flexible hose or a breakable coupling can be used in the water feed line, but neither option really offers a satisfactory solution to the problem. Routing the flexible hose in such a manner to still allow easy use of the machine door is difficult, and a breakable coupling is a potential source of leakage over time as its seal wears out with extended use.
In some alternative arrangements the spray nozzle is mounted at the rear of the drum, again on axis, or outside the drum surface, spraying through its perforations. In such an arrangement, although the machine door is left unmodified, there is either an issue with inefficient wetting of the load from an on-axis spray to consider, as with the system of FR-A-2525645, or problems arise with wastage of water, as the spray hits the drum outer wall rather than passing through the perforations therein.
Such difficulties have to be addressed in the case of standard washing operations involving the use of detergents and water, but these problems are exacerbated when using solid particulate cleaning material (e.g. polymer beads) in the washing process, and such processes present similar, but much more demanding, problems in facilitating the transportation of beads into the drum.
In the case of the apparatus of WO-A-2011/098815, it is disclosed that the access means typically comprises a hinged door mounted in the casing, which may be opened to allow access to the inside of the cylindrical cage, and which may be closed in order to provide a substantially sealed system. The door typically includes a window and at least one addition port which facilitates the addition of materials to the rotatably mounted cylindrical cage. In operation, the solid particulate cleaning material is added to the load in the cylindrical cage via a feed tube mounted on the machine door (access means).
Hence, this and other current washing machines using this type of bead cleaning technology, like conventional washing machines, also introduce cleaning materials such as beads through the machine door, and have, as a consequence, also been subject to the same problems associated with these conventional machines. Such an arrangement is, therefore, also not ideal and the present invention seeks to address this issue by providing alternative means for the introduction of these materials into the apparatus.

SUMMARY OF THE INVENTION

Thus, according to a first aspect of the present invention, there is provided an apparatus for use in the cleaning of soiled substrates, said apparatus comprising housing means comprising:
(a) a stationary member;
(b) a rotatably mounted cylindrical cage; and
(c) access means,
wherein said stationary member comprises an annular planar member which is of greater internal diameter than said access means and is located adjacent said rotatably mounted cylindrical cage and said stationary member comprises a multiplicity of delivery means which are mounted thereon and a multiplicity of orifices which are respectively operably connected to said multiplicity of delivery means, wherein said multiplicity of delivery means is adapted to facilitate the delivery of materials into said rotatably mounted cylindrical cage.
In certain embodiments of the invention said rotatably mounted cylindrical cage comprises a drum comprising perforated side walls, wherein up to 60% of the surface area of said side walls comprises perforations, and said perforations comprise holes having a diameter of no greater than 25.0 mm.
In typical embodiments of the invention, no more than 50%, more preferably no more than 40%, of the side walls comprises perforations.
In embodiments of the invention, said perforations comprise holes having a diameter of from 2 to 25 mm, preferably from 4 to 10 mm, most preferably from 5 to 8 mm.
Said access means typically comprises at least one hinged door mounted in the housing means, which may be opened to allow access to the inside of the cylindrical cage, and which may be closed in order to provide a substantially sealed system. Preferably, the door includes a window.
The rotatably mounted cylindrical cage may be mounted about an essentially vertical axis within the housing means but, most preferably, is mounted about an essentially horizontal axis within said housing means. Consequently, in preferred embodiments of the invention, said access means is located in the front of the apparatus, providing a front-loading facility. When the rotatably mounted cylindrical cage is vertically mounted within the housing means, the access means is located in the top of the apparatus, providing a top-loading facility. However, for the purposes of the further description of the present invention, it will be assumed that said rotatably mounted cylindrical cage is mounted horizontally within said housing means.
Said rotatably mounted cylindrical cage is of the size which is to be found in most commercially available washing machines and tumble driers, and may 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 120 litres whilst, for an industrial washer-extractor, capacities anywhere in the range of from 120 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 1150 litres, more typically 450 to 650 litres and, in such cases, said cage 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. Generally, the cage will have 10 litres of volume per kg of washload to be cleaned.
Said stationary member is comprised in said housing means and typically attached thereto by attachment means incorporating fixing members. Necessarily, said stationary member is not fixedly attached to any moving components within said apparatus and, specifically, is located adjacent, but not fixedly attached to, said rotatably mounted cylindrical cage. Optionally, said stationary member may be intrinsically comprised as part of said housing means.
Said stationary member typically comprises a metallic member, most frequently formed of steel, which may, for example, be formed by pressing, machining, or other suitable fabrication processes. Optionally, said stationary member may comprise a plastic member, formed by moulding.
In typical embodiments of the invention, said rotatably mounted cylindrical cage is mounted in a first upper chamber of said housing means and said apparatus additionally comprises a second lower chamber located beneath said cylindrical cage. Optimally, said apparatus additionally comprises at least one recirculation means and/or pumping means.
Thus, in a preferred embodiment, said apparatus according to the present invention, for use in the cleaning of soiled substrates, comprises housing means comprising:

- (a) a first upper chamber having mounted therein a rotatably mounted cylindrical cage and a stationary member;
- (b) a second lower chamber located beneath said cylindrical cage;
- (c) at least one recirculation means;
- (d) access means;
- (e) pumping means; and
- (f) a multiplicity of delivery means,
  wherein said stationary member comprises an annular planar member which is of greater internal diameter than said access means and is located adjacent said rotatably mounted cylindrical cage and said stationary member comprises a multiplicity of delivery means which are mounted thereon and a multiplicity of orifices which are respectively operably connected to said multiplicity of delivery means, wherein said multiplicity of delivery means is adapted to facilitate the delivery of materials into said rotatably mounted cylindrical cage.

Rotation of said rotatably mounted cylindrical cage is effected by use of drive means, which typically comprises electrical drive means, in the form of an electric motor. Operation of said drive means is effected by control means which may be programmed by an operative.
Said apparatus is designed to operate in conjunction with soiled substrates and cleaning media comprising a solid particulate material, which is most preferably in the form of a multiplicity of polymeric particles. These polymeric particles are required to be efficiently circulated to promote effective cleaning and the apparatus, therefore, preferably includes circulation means. Thus, the inner surface of the cylindrical side walls of said rotatably mounted cylindrical cage preferably comprises a multiplicity of spaced apart elongated protrusions affixed essentially perpendicularly to said inner surface. Preferably, said protrusions 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 comprises from 3 to 10, most preferably 4, of said protrusions, which are commonly referred to as lifters.
In operation, agitation is provided by rotation of said rotatably mounted cylindrical cage. However, in preferred embodiments of the invention, there is also provided additional agitating means, in order to facilitate the efficient removal of residual solid particulate material at the conclusion of the cleaning operation. Preferably, said agitating means comprises an air jet.
Preferably, said rotatably mounted cylindrical cage is located within a first upper chamber of said housing means and beneath said first upper chamber is located a second lower chamber which functions as a collection chamber for said cleaning media. Preferably, said lower chamber comprises an enlarged sump.
Said housing means includes standard plumbing features, thereby providing at least one recirculation means, in addition to said multiplicity of delivery means attached to said stationary member, by virtue of which at least water and, optionally, cleaning agents such as surfactants, in addition to said solid particulate cleaning material, may initially be introduced into the rotatably mounted cylindrical cage within said apparatus.
Said apparatus may additionally comprise means for circulating air within said housing means, and for adjusting the temperature and humidity therein. Said means may typically include, for example, a recirculating fan, an air heater, a water atomiser and/or a steam generator. Additionally, sensing means may also be provided for determining, inter alia, the temperature and humidity levels within the apparatus, and for communicating this information to the control means.
Said apparatus typically comprises at least one recirculation means, thereby facilitating recirculation of said solid particulate material from said lower chamber to said rotatably mounted cylindrical cage, for re-use in cleaning operations. Preferably, said first recirculation means comprises ducting connecting said second chamber and said rotatably mounted cylindrical cage. More preferably, said ducting comprises separating means for separating said solid particulate material from water, and diverting said solid particulate material into said cylindrical cage. Typically, said separating means comprises a filter material such as wire mesh located in a receptor vessel above said cylindrical cage, said filter material being positioned, typically at a suitable predetermined angle, so as to divert the bead flow from said receptor vessel, via said multiplicity of delivery means and said stationary member, to the interior of the cylindrical cage.
Recirculation of solid particulate matter from said lower chamber to said rotatably mounted cylindrical cage is achieved by the use of pumping means comprised in said first recirculation means, wherein said pumping means is adapted to deliver said solid particulate matter to said separating means, which is adapted to control the re-entry of said solid particulate matter into said rotatably mounted cylindrical cage.
Preferably, said apparatus additionally includes a second recirculation means, allowing for the return of water separated by said separating means to said lower chamber, thereby facilitating re-use of said water in an environmentally beneficial manner.
Preferably, said lower chamber comprises additional pumping means to promote circulation and mixing of the contents thereof, in addition to heating means, allowing the contents to be raised to a preferred temperature of operation.
In operation, during a typical cycle, soiled garments are first placed into said rotatably mounted cylindrical cage. Then, the solid particulate material and the necessary amount of water, together with any required additional cleaning agent, are added to said rotatably mounted cylindrical cage via the delivery means comprised in said stationary member. Optionally, said materials are heated to the desired temperature, optionally in the lower chamber comprised in the housing means and introduced, via the first recirculation means, into the cylindrical cage. Alternatively, said cleaning agent may, for example, be pre-mixed with water prior to introduction into said cylindrical cage via said delivery means. Optionally, this water may be heated. Additional cleaning agents, of which bleach is a typical example, may be added with more, optionally heated, water at later stages during the wash cycle, using the same means.
During the course of agitation by rotation of the cage, the fluids and a quantity of the solid particulate material fall through the perforations in the cage and into the lower chamber of the apparatus. Thereafter, the solid particulate material may be re circulated via the first recirculation means such that it is transferred to said separating means, from which it is returned to the cylindrical cage for continuation of the washing operation. This process of continuous circulation of the solid particulate material carries on throughout the washing operation until cleaning is completed.
Thus, the solid particulate material which falls through the perforations in the walls of said rotatably mounted cylindrical cage and into said lower chamber is carried to the top side of said rotatably mounted cylindrical cage, wherein it is diverted from said receptor vessel by said separation means and transported via said multiplicity of delivery means mounted on said stationary member back into said cage, thereby to continue the cleaning operation.
According to a second aspect of the present invention, there is provided a method for cleaning a soiled substrate, said method comprising the treatment of the substrate with a formulation comprising solid particulate cleaning material and wash water, wherein said method is carried out in an apparatus according to the first aspect of the invention.
Preferably, said method comprises the steps of:

- (a) introducing a solid particulate cleaning material and water into the second chamber of an apparatus according to the first aspect of the invention;
- (b) agitating and heating said solid particulate cleaning material and water;
- (c) loading at least one soiled substrate into said rotatably mounted cylindrical cage via access means;
- (d) closing the access means so as to provide a substantially sealed system;
- (e) causing the rotatably mounted cylindrical cage to rotate whilst introducing said wash water and any required additional cleaning agent to uniformly wet out the substrate;
- (f) introducing said solid particulate cleaning material into said rotatably mounted cylindrical cage and operating the apparatus for a wash cycle, wherein said rotatably mounted cylindrical cage continues to rotate, and wherein fluids and solid particulate cleaning material are caused to fall through perforations in said rotatably mounted cylindrical cage into said second chamber in a controlled manner;
- (g) operating pumping means so as to transfer fresh solid particulate cleaning material and recycle used solid particulate cleaning material to separating means;
- (h) adding said fresh and recycled solid particulate cleaning material to said rotatably mounted cylindrical cage in a controlled manner; and
- (i) continuing with steps (f), (g) and (h) as required to effect cleaning of the soiled substrate.

Preferably, additional cleaning agents are employed in said method. Said additional cleaning agents may be added to the lower chamber of said apparatus with said solid particulate cleaning material, optionally heated to the desired temperature therein and introduced, via the first recirculation means, into the cylindrical cage. Preferably, however, said additional cleaning agents are pre-mixed with water, which mixture may optionally be heated before addition to said cylindrical cage via said multiplicity of delivery means attached to said stationary member. Optionally, this addition may be carried out using one or more spray nozzles in order to better distribute said cleaning agents in the washload.
Preferably, pumping of said fresh and recycled solid particulate cleaning material proceeds at a rate sufficient to maintain approximately the same level of cleaning material in said rotatably mounted cylindrical cage throughout the cleaning operation, and to ensure that the ratio of cleaning material to soiled substrate stays substantially constant until the wash cycle has been completed.
The generation of suitable G forces, in combination with the action of the solid particulate cleaning material, is a key factor in achieving an appropriate level of cleaning of the soiled substrate. G is a function of the cage size and the speed of rotation of the cage and, specifically, is the ratio of the centripetal force generated at the inner surface of the cage to the static weight of the washload. Thus, for a cage of inner radius r (m), rotating at R (rpm), with a washload of mass M (kg), and an instantaneous tangential velocity of the cage v (m/s), and taking g as the acceleration due to gravity at 9.81 m/s²:
Centripetal force=Mv ² /r
Washload static weight=Mg
v=2πrR/60
Hence, G=4π² r ² R ²/3600rg=4π² rR ²/3600g=1.118×10⁻³ rR ²
When, as is usually the case, r is expressed in centimetres, rather than metres, then:
G=1.118×10⁻⁵ rR ²
Hence, for a drum of radius 49 cm rotating at 800 rpm, G=350.6.
In a typical embodiment of the invention, a cylindrical drum having a diameter of 98 cm is rotated at a speed of 30-800 rpm in order to generate G forces of 0.49-350.6 at different stages during the cleaning process. In examples of alternative embodiments of the invention, a 48 cm diameter drum rotating at 1600 rpm can generate 687 G, whilst a 60 cm diameter drum at the same speed of rotation generates 859 G.
In particular embodiments of the invention, the claimed method additionally provides for separation and recovery of the solid particulate cleaning material, and this may then be re-used in subsequent washes.
During the wash cycle, rotation of said rotatably mounted cylindrical cage is preferably caused to occur at rotation speeds such that G is <1 which, for a 98 cm diameter cage, requires a rotation speed of up to 42 rpm, with preferred rates of rotation being between 30 and 40 rpm.
On completion of the wash cycle, feeding of solid particulate cleaning material into the rotatably mounted cylindrical cage ceases and the speed of rotation of the cage is initially increased in order to effect a measure of drying of the cleaned substrate, thereby generating G forces of between 10 and 1000, more specifically between 40 and 400. Typically, for a 98 cm diameter cage, rotation is at a speed of up to 800 rpm in order to achieve this effect. Subsequently, rotation speed is reduced and returned to the speed of the wash cycle so as to allow for removal of the solid particulate cleaning material.
Optionally, following said bead removal operation, said method may additionally comprise a rinsing operation, wherein additional water may be added to said rotatably mounted cylindrical cage in order to effect complete removal of any additional cleaning agent employed in the cleaning operation. Water is added to said cylindrical cage via said multiplicity of delivery means attached to said stationary member. Again, addition may optionally be carried out by means of one or more spray nozzles in order to achieve better distribution of the rinsing water in the washload.
Alternatively, said addition may be made by overfilling the second, lower chamber of said apparatus with water such that it enters the first, upper chamber and thereby partially submerges said rotatably mounted cylindrical cage and enters into said cage. Following rotation at the same speed as during the wash cycle, water is removed from said cage by allowing the water level to fall as appropriate and the speed of rotation of the cage is then increased so as to achieve a measure of drying of the substrate. Typically, for a 98 cm diameter cage, rotation is at a speed of up to 800 rpm in order to achieve this effect. Subsequently, rotation speed is reduced and returned to the speed of the wash cycle, thereby allowing for final removal of any remaining solid particulate cleaning material. Said rinsing and drying cycles may be repeated as often as desired.
Optionally, said rinse cycle may be used for the purposes of substrate treatment, involving the addition of treatment agents such as anti-redeposition additives, optical brighteners, perfumes, softeners and starch to the rinse water via said multiplicity of delivery means mounted on said stationary member.
Said solid particulate cleaning material is preferably subjected to a cleaning operation in said lower chamber by sluicing said chamber with clean water in the presence or absence of a cleaning agent, such as a surfactant. Optionally, this water may be heated. Alternatively, cleaning of the solid particulate cleaning material may be achieved as a separate stage in said rotatably mounted cylindrical cage, again using water which may optionally be heated.
Generally, any remaining solid particulate cleaning material on said at least one substrate may be easily removed by shaking the at least one substrate. If necessary, however, further remaining solid particulate cleaning material may be removed by suction means, preferably comprising a vacuum wand.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be further illustrated by reference to the following drawings, wherein:

FIGS. 1 and 2 both show an apparatus according to the invention, and particularly illustrate the deployment of the stationary member and the multiplicity of delivery means in the apparatus.

DETAILED DESCRIPTION OF THE INVENTION

The present inventors have addressed the issues associated with the introduction of materials into cleaning apparatus via access means such as machine doors by providing alternative means for the introduction of these materials into such apparatus and, as a consequence, have developed an apparatus for use in the cleaning of soiled substrates, said apparatus comprising housing means comprising:
(a) a stationary member;
(b) a rotatably mounted cylindrical cage; and
(c) access means,
wherein said stationary member comprises an annular planar member which is of greater internal diameter than said access means and is located adjacent said rotatably mounted cylindrical cage and said stationary member comprises a multiplicity of delivery means which are mounted thereon and a multiplicity of orifices which are respectively operably connected to said multiplicity of delivery means, wherein said multiplicity of delivery means is adapted to facilitate the delivery of materials into said rotatably mounted cylindrical cage.
Said stationary member is comprised in said housing means and typically attached thereto by attachment means incorporating fixing members. Necessarily, said stationary member is not fixedly attached to any moving components within said apparatus and, specifically, is located adjacent, but not fixedly attached to, said rotatably mounted cylindrical cage. Optionally, said stationary member may be intrinsically comprised as part of said housing means.
Said stationary member typically comprises a metallic member, most frequently formed of steel, which may, for example, be formed by pressing, machining, or other suitable fabrication processes. Optionally, said stationary member may comprise a plastic member, formed by moulding.
In typical embodiments of the invention, said stationary member comprises a flat, annular ring piece of larger internal diameter than the access means, which is typically a door. The stationary member is located within the housing means, but is not attached to any rotating parts. This stationary member may be adapted to suit the requirements of the specific washing machine, i.e. the desired placement and shape of any inlets for cleaning materials, or water spray nozzles, within the housing means but outside the perimeter of the access means, or door.
Typically, the stationary member effectively replaces some of the inner part of the front of the rotatably mounted cylindrical cage and, as a consequence, it is necessary that the edges of said stationary member should be smoothed, in order to avoid damage to the soiled substrate in the load, particularly when this comprises textile substrates. Additionally, the gap around the circumference between the stationary member and the rotating cylindrical cage is required to be sufficiently small to prevent trapping of the soiled substrate. This gap may range from 1-25 mm, more often from 2-10 mm. More typically, however, it is found that a gap in the region of from 3-5 mm suffices for this purpose. The essential requirement in this regard is that water and solid particulate cleaning materials may suitably be added via the multiplicity of delivery means associated with the stationary member, through individual spray nozzles or particulate material inlets respectively, without constraining the operability, or reducing the size, of the access means.
Thus, in a typical commercial washing apparatus, the stationary member may comprise a disc of metal, most frequently steel, which is formed by pressing, machining, or other suitable fabrication processes, and wherein the outer edges of the disc are rolled to prevent damage to the substrate which is being treated. Typical domestic washing machines frequently use plastic mouldings in the doors comprising their access means and, hence, the stationary member in such an arrangement could also be such a moulding with smoothed edges.
The apparatus according to the invention may conveniently be derived by modification of the apparatus disclosed in WO-A-2011/098815.
The apparatus according to the invention may be used for the cleaning of any of a wide range of substrates including, for example, plastics materials, leather, paper, cardboard, metal, glass or wood. In practice, however, said apparatus is principally designed for use in the cleaning of substrates comprising textile fibre garments, 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, or man-made and synthetic textile fibres, for example nylon 6,6, polyester, cellulose acetate, or fibre blends thereof.
The apparatus of the invention may be used for conventional aqueous washing processes as well as for the so-called bead-technology washing processes which involve the use of a solid particulate cleaning material. In such processes, the solid particulate cleaning material most preferably comprises a multiplicity of polymeric particles. Typically, the polymeric particles comprise polyalkenes such as polyethylene and polypropylene, polyamides, polyesters or polyurethanes, which may be foamed or unfoamed.
Furthermore, said polymers may be linear or crosslinked. Preferably, however, said polymeric particles comprise polyamide or polyester particles, most particularly particles of nylon, polyethylene terephthalate or polybutylene terephthalate, most preferably 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 or polyester homo- or co-polymers may be used including, but not limited to, Nylon 6, Nylon 6,6, polyethylene terephthalate and polybutylene terephthalate. Preferably, the nylon comprises Nylon 6,6 homopolymer having a molecular weight in the region of from 5000 to 30000 Daltons, preferably from 10000 to 20000 Daltons, most preferably from 15000 to 16000 Daltons. The polyester will typically have a molecular weight corresponding to an intrinsic viscosity measurement in the range of from 0.3-1.5 dl/g as measured by a solution technique such as ASTM D-4603.
Optionally, copolymers of the above polymeric materials may be employed for the purposes of the invention. Specifically, the properties of the polymeric materials may be tailored to specific requirements by the inclusion of monomeric units which confer particular properties on the copolymer. Thus, the copolymers may be adapted to attract particular staining materials by including monomer units in the polymer chain which, inter a/ia, are ionically charged, or include polar moieties or unsaturated organic groups. Examples of such groups may include, for example, acid or amino groups, or salts thereof, or pendant alkenyl groups.
The polymeric particles are of such a shape and size as to allow for good flowability and intimate contact with the 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 comprise cylindrical or spherical beads.
The particles may have smooth or irregular surface structures and can be of solid or hollow construction. Particles are of such a size as to have an average mass of 1-35 mg, preferably from 10-30 mg, more preferably from 12-25 mg, and with a surface area of 10-120 mm², preferably from 15-50 mm², more preferably from 20-40 mm².
In the case of cylindrical beads, the preferred particle diameter is in the region of from 1.0 to 6.0 mm, more preferably from 1.5 to 4.0 mm, most preferably from 2.0 to 3.0 mm, and the length of the beads is preferably in the range from 1.0 to 4.0 mm, more preferably from 1.5 to 3.5 mm, and is most preferably in the region of 2.0 to 3.0 mm.
Typically, for spherical beads, the preferred diameter of the sphere is in the region of from 1.0 to 6.0 mm, more preferably from 2.0 to 4.5 mm, most preferably from 2.5 to 3.5 mm.
In order to provide additional lubrication to the cleaning system and thereby improve the transport properties within the system, water is added to the system. Thus, more efficient transfer of the at least one cleaning material to the substrate is facilitated, and removal of soiling and stains from the substrate occurs more readily. Optionally, the soiled substrate may be moistened by wetting with mains or tap water prior to loading into the apparatus of the invention. In any event, water is added to the rotatably mounted cylindrical cage of the apparatus according to the invention such that the washing treatment is carried out so as to achieve a wash water to substrate ratio which is preferably between 2.5:1 and 0.1:1 w/w; more preferably, the ratio is between 2.0:1 and 0.8:1, with particularly favourable results having 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 is introduced into the rotatably mounted cylindrical cage of the apparatus according to the invention after loading of the soiled substrate into said cage. An additional amount of water will migrate into the cage during the circulation of the solid particulate cleaning material, but the amount of carry over is minimised by the action of the separating means.
Whilst, in one embodiment, the method of the invention envisages the cleaning of a soiled substrate by the treatment of a moistened substrate with a formulation which essentially consists only of a multiplicity of polymeric particles, in the absence of any further additives, optionally in other embodiments the formulation employed may additionally comprise at least one cleaning agent. Said at least one cleaning agent may include at least one cleaning material. Preferably, the at least one cleaning material comprises at least one detergent composition. Optionally, said at least one cleaning material is mixed with said polymeric particles but, in a preferred embodiment, each of said polymeric particles is coated with said at least one cleaning material.
The principal components of the detergent composition comprise cleaning components and post-treatment components. Typically, the cleaning components comprise surfactants, enzymes and bleach, whilst the post-treatment components include, for example, anti-redeposition additives, perfumes and optical brighteners.
However, the detergent formulation may 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.
Examples of suitable surfactants may be selected from non-ionic and/or anionic and/or cationic surfactants and/or ampholytic and/or zwitterionic and/or semi-polar nonionic surfactants. The surfactant is typically present at a level of from about 0.1%, from about 1%, or even from about 5% by weight of the cleaning compositions to about 99.9%, to about 80%, to about 35%, or even to about 30% by weight of the cleaning compositions.
The compositions may include one or more detergent enzymes which provide cleaning performance and/or fabric care benefits. Examples of suitable enzymes include, but are not limited to, hemicellulases, peroxidases, proteases, other cellulases, other xylanases, lipases, phospholipases, esterases, cutinases, pectinases, keratanases, reductases, oxidases, phenoloxidases, lipoxygenases, ligninases, pullulanases, tannases, pentosanases, malanases, [beta]-glucanases, arabinosidases, hyaluronidase, chondroitinase, laccase, and amylases, or mixtures thereof. A typical combination may comprise a mixture of enzymes such as protease, lipase, cutinase and/or cellulase in conjunction with amylase.
Optionally, enzyme stabilisers may also be included amongst the cleaning components. In this regard, enzymes for use in detergents may be stabilised by various techniques, for example by the incorporation of water-soluble sources of calcium and/or magnesium ions in the compositions.
The compositions may include one or more bleach compounds and associated activators. Examples of such bleach compounds include, but are not limited to, peroxygen compounds, including hydrogen peroxide, inorganic peroxy salts, such as perborate, percarbonate, perphosphate, persilicate, and mono persulphate salts (e.g. sodium perborate tetrahydrate and sodium percarbonate), and organic peroxy acids such as peracetic acid, monoperoxyphthalic acid, diperoxydodecanedioic acid, N,N′-terephthaloyl-di(6-aminoperoxycaproic acid), N,N′-phthaloylaminoperoxycaproic acid and amidoperoxyacid. Bleach activators include, but are not limited to, carboxylic acid esters such as tetraacetylethylenediamine and sodium nonanoyloxybenzene sulphonate.
Suitable builders may be included in the formulations and these include, but are not limited to, the alkali metal, ammonium and alkanolammonium salts of polyphosphates, alkali metal silicates, alkaline earth and alkali metal carbonates, aluminosilicates, polycarboxylate compounds, ether hydroxypolycarboxylates, copolymers of maleic anhydride with ethylene or vinyl methyl ether, 1,3,5-trihydroxybenzene-2,4,6-trisulphonic acid, and carboxymethyl-oxysuccinic acid, various alkali metal, ammonium and substituted ammonium salts of polyacetic acids such as ethylenediamine tetraacetic acid and nitrilotriacetic acid, as well as polycarboxylates such as mellitic acid, succinic acid, oxydisuccinic acid, polymaleic acid, benzene 1,3,5-tricarboxylic acid, carboxymethyloxysuccinic acid, and soluble salts thereof.
The compositions may also optionally contain one or more copper, iron and/or manganese chelating agents and/or one or more dye transfer inhibiting agents.
Suitable polymeric dye transfer inhibiting agents include, but are not limited to, polyvinylpyrrolidone polymers, polyamine N-oxide polymers, copolymers of N-vinylpyrrolidone and N-vinylimidazole, polyvinyloxazolidones and polyvinylimidazoles or mixtures thereof.
Optionally, the detergent formulations can also contain dispersants. Suitable water-soluble organic materials are the homo- or co-polymeric acids or their salts, in which the polycarboxylic acid may comprise at least two carboxyl radicals separated from each other by not more than two carbon atoms.
Said anti-redeposition additives are physico-chemical in their action and include, for example, materials such as polyethylene glycol, polyacrylates and carboxy methyl cellulose.
Optionally, the compositions may also contain perfumes Suitable perfumes are generally multi-component organic chemical formulations which can contain alcohols, ketones, aldehydes, esters, ethers and nitrile alkenes, and mixtures thereof. Commercially available compounds offering sufficient substantivity to provide residual fragrance include Galaxolide (1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta(g)-2-benzopyran), Lyral (3- and 4-(4-hydroxy-4-methyl-pentyl)cyclohexene-1-carboxaldehyde and Ambroxan ((3aR,5aS,9aS,9bR)-3a,6,6,9a-tetramethyl-2,4,5,5a,7,8,9,9b-octahydro-1H-benzo[e][1]benzofuran). One example of a commercially available fully formulated perfume is Amour Japonais supplied by Symrise® AG.
Suitable optical brighteners fall into several organic chemical classes, of which the most popular are stilbene derivatives, whilst other suitable classes include benzoxazoles, benzimidazoles, 1,3-diphenyl-2-pyrazolines, coumarins, 1,3,5-triazin-2-yls and naphthalimides. Examples of such compounds include, but are not limited to, 4,4′-bis[[6-anilino-4(methylamino)-1,3,5-triazin-2-yl]amino]stilbene-2,2′-disulphonic acid, 4,4′-bis[[6-anilino-4-[(2-hydroxyethyl)methylamino]-1,3,5-triazin-2-yl]amino]stilbene-2,2′-disulphonic acid, disodium salt, 4,4′-Bis[[2-anilino-4-[bis(2-hydroxyethy)amino]-1,3,5-triazin-6-yl]amino]stilbene-2,2′-disulphonic acid, disodium salt, 4,4′-bis[(4,6-dianilino-1,3,5-triazin-2-yl)amino]stilbene-2,2′-disulphonic acid, disodium salt, 7-diethylamino-4-methylcoumarin, 4,4′-Bis[(2-anilino-4-morpholino-1,3,5-triazin-6-yl)amino]-2,2′-stilbenedisulphonic acid, disodium salt, and 2,5-bis(benzoxazol-2-yl)thiophene.
Said agents may be used either alone or in any desired combination and may be added to the cleaning system at appropriate stages during the cleaning cycle in order to maximise their effects.
In any event, however, when the method of the invention is performed in the presence of at least one additional cleaning agent, the quantity of said cleaning agent required in order to achieve satisfactory cleaning performance is significantly reduced from the quantities required with the conventional methods of the prior art. This, in turn, has beneficial effects in terms of the reduced quantity of rinse water that is subsequently required to be used.
The ratio of solid particulate cleaning material to substrate is generally in the range of from 0.1:1 to 10:1 w/w, preferably in the region of from 0.5:1 to 5:1 w/w, with particularly favourable results being achieved with a ratio of between 1:1 and 3:1 w/w, and especially at around 2:1 w/w. Thus, for example, for the cleaning of 5 g of fabric, 10 g of polymeric particles, optionally coated with surfactant, would be employed in one embodiment of the invention. The ratio of solid particulate cleaning material to substrate is maintained at a substantially constant level throughout the wash cycle.
The apparatus and the method of the present invention may be used for either small or large scale batchwise processes and find application in both domestic and industrial cleaning processes. The apparatus of the present invention may be used to carry out conventional washing processes as well as for the performance of the claimed method of the present invention.
As previously noted, the method of the invention finds 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 according to the method of the invention at, for example, temperatures of between 5 and 95° C. for a duration of between 5 and 120 minutes in a substantially sealed system. Thereafter, additional time is required for the completion of the rinsing and bead separation stages of the overall process, so that the total duration of the entire cycle is typically in the region of 1 hour. The preferred operating temperatures for the method of the invention are in the range of from 10 to 60° C. and, more preferably, from 15 to 40° C.
The cycle for removal of solid particulate material may optionally be performed at room temperature and it has been established that optimum results are achieved at cycle times of between 2 and 30 minutes, preferably between 5 and 20 minutes.
The results obtained are very much in line with those observed when carrying out conventional washing and laundering procedures with textile fabrics. The extent of cleaning and stain removal achieved with fabrics treated by the method 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 of the method 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.
Additionally, it has been demonstrated that re-utilisation of the polymer particles is possible, allowing for the performance of multiple washes with the same solid particulate cleaning material. Re-use of the particles in this way for repeat cleaning procedures provides significant economic benefits and the achievement of satisfactory results after multiple washes is assisted by the nature of the process, which relies on continuous cleaning of the particulate cleaning material as an integral part of the procedure, although it generally found that some deterioration in performance is eventually observed.
In a typical example of an operating cycle according to the method of the invention, additional cleaning agents are employed. Said additional cleaning agents may be added to the lower chamber of said apparatus with said solid particulate cleaning material, optionally heated to the desired temperature therein, and introduced via the first recirculation means into the cylindrical cage. Preferably, however, said additional cleaning agents are pre-mixed with water, which mixture may optionally be heated before addition to said cylindrical cage via said multiplicity of delivery means attached to said stationary member. Optionally, this addition may be carried out using one or more spray nozzles in order to better distribute said cleaning agents in the washload.
Thereafter, an initial addition of solid particulate cleaning material (approximately 50 kg) is added to a washload of soiled substrate (25 kg) in the rotatably mounted cylindrical cage of 98 cm diameter, after which rotation of the cage commences at around 40 rpm. Thereafter, recirculation of solid particulate cleaning material is achieved by pumping into said rotatably mounted cylindrical cage via the separating means approximately every 30 seconds throughout the duration of the wash cycle, which may typically continue for around 30 minutes. The system is thereby designed to pump and add solid particulate cleaning material at a sufficient rate to maintain roughly the same level of solid particulate cleaning material in the rotatably mounted cylindrical cage (approximately 2:1 by weight, for 50 kg of beads and 25 kg of cloth) throughout the wash.
Thus, during the wash cycle, the solid particulate cleaning material is continually falling out of the rotatably mounted cylindrical cage through its perforations, and is being recycled and added, together with fresh cleaning material, via the separating means and multiplicity of delivery means attached to the stationary member. This process may either be controlled manually, or operated automatically. The rate of exit of the solid particulate cleaning material from the rotatably mounted cylindrical cage is essentially controlled by means of its specific design. The key parameters in this regard include the size of the perforations, the number of perforations and the pattern of the perforations.
Generally, the perforations are sized at around 2-3 times the average particle diameter of the solid particulate cleaning material which, in a typical example, results in perforations having a diameter of no greater than 10.0 mm. Up to 60% of the surface area of the cylindrical walls of the cage typically comprises perforations.
The rate of exit of the solid particulate cleaning material from the rotatably mounted cylindrical cage is also affected by the speed of rotation of said cage, with higher rotation speeds increasing the centripetal force so as to increase the tendency to push the solid particulate cleaning material out of the perforations. However, higher cage rpm values also compress the substrate being cleaned, so as to trap the cleaning material within folds thereof. The most suitable rotation speeds are, therefore, generally found to be between 30 and 40 rpm at 98 cm cage diameter, or those which generate G values of between 0.49 and 0.88. The maximum rotation speed in order to avoid bead trapping in garments is found to be around 42 rpm (G=0.97).
In addition, the moisture level in the wash also has an effect, with wetter substrates tending to retain cleaning material for a longer time than drier substrates. Consequently, overwetting of substrate can, if necessary, be employed in order to further control the rate of exit of solid particulate cleaning material.
On completion of the wash cycle, addition of solid particulate cleaning material to the rotatably mounted cylindrical cage is ceased, and the cage is rotated for a short time (about 2 minutes) at low rpm (30-40 rpm; G=0.49-0.88) to allow the bulk of the solid particulate cleaning material to leave the cage. The cage is then rotated at high speed (between 300 and 800 rpm; G=49.3-350.6) for about 2 minutes in order to extract some liquid and dry the substrate to an extent. The rotation speed is then returned to the same low rpm as in the wash cycle in order to complete the removal of cleaning material; this generally takes around 20 minutes.
The method of the invention has been shown to be particularly successful in the removal of cleaning material from the cleaned substrate after washing, and tests with cylindrical polyester beads, and nylon beads comprising Nylon 6,6 polymer, have indicated bead removal efficacy such that on average <20 beads per garment remain in the washload at the end of the bead separation cycle. Generally, this can be further reduced to an average of <10 beads per garment and, in optimised cases wherein a 20 minute separation cycle is employed, an average of <5 beads per garment is typically achieved.
Following said bead removal operation a series of rinses is carried out, wherein additional water is sprayed via the delivery means into the rotatably mounted cylindrical cage in order to effect complete removal of any additional cleaning agent employed in the cleaning operation. In an embodiment of the invention, said delivery means incorporate one or more spray nozzles through which said water is sprayed, these nozzles being attached to said stationary member. The use of said spray nozzles has been shown to better distribute the rinsing water in the washload. By this means the overall water consumption during the rinsing operation can also be minimised (3:1 rinse water:cloth, typically, per rinse). The cage is rotated at low speeds again during rinse water addition (30-40 rpm, G=0.49-0.88 for 98 cm diameter cage), but after this operation has ceased the cage speed is once again increased to achieve a measure of drying of the substrate (300-800 rpm, G=49.3-350.6). Subsequently, rotation speed is reduced and returned to the speed of the wash cycle so as to allow for final removal of any remaining solid particulate cleaning material. Said rinsing and drying cycles may be repeated as often as desired (3 times is typical).
Optionally, the bead removal operation may be carried out between rinses, rather than before the start of the series of rinses.
Turning now to the Figures provided herewith, there are seen in FIGS. 1 and 2 illustrations of an apparatus according to one embodiment of the invention. FIG. 1 shows a front view of a typical commercial bead washing machine wherein the external cladding panels have been removed for the sake of clarity. Thus, there can be seen housing means including housing chamber (1) wherein is located the rotatably mounted cylindrical cage (not shown). An access means in the form of door (2) is located on the front of the housing means and a multiplicity of delivery means comprising bead inlet (3), water spray nozzles (4) and fixed plumbing (5) are provided to allow the cleaning materials to enter the rotatably mounted cylindrical cage.
Specifically, door (2) is located on the axis of the cylindrical cage, and hinged to the right. Visible above the door are bead inlet (3), and a pair of water spray nozzles (4). The bead inlet (3) is positioned above the access means, and at the top end of the cylindrical cage, thereby enhancing the ability of the introduced cleaning materials to mix into a wash load during a wash cycle. The bead inlet is typically connected to separation means which provides a source of solid particulate cleaning material and, on each side of the bead inlet are located the water spray nozzles, which are connected via fixed plumbing (5) to the water supply. It will be noted that both the water spray nozzles and the bead inlet are located higher than could have been achieved if they were mounted on the access means (2). It is also the case that the use of multiple water spray nozzles and bead inlets may also be contemplated in order to provide quicker and more uniform addition of cleaning materials to the cylindrical cage.
FIG. 2 shows the same view as FIG. 1, but the front of the housing chamber (1) and the access means (2) have been removed so as provide a clearer illustration of the function of the stationary member. Thus, stationary member (6) is visible outside the door aperture and its outer edge (7) provides the interface with rotating front (8) of the rotatably mounted cylindrical cage. The gap around the circumference between the stationary member and the rotating cylindrical cage is required to be sufficiently small to prevent trapping of the soiled substrate and, in the illustrated embodiment, there is a uniform gap of 4±1 mm. The stationary member is fixedly attached to the inside of the front of the housing chamber (1) via attachment means comprising an attachment piece (9) by the use of fixing members (10). Due to the fixed attachment to the housing chamber, the attachment piece (9) ensures that the stationary member does not rotate.
Thus, it is seen that the placement of the bead inlet (3) and the water spray nozzles (4) is such that they are spaced at a distance from the access means comprising door (2), and they are securely attached to fixed plumbing (5) and fixed in place by attachment to the stationary member (6). This member (6) is securely attached to the inside of the housing chamber (1) via attachment piece (9). This overcomes the problems associated with the incorporation of the delivery means in in the access means and eliminates the consequent difficulties which can occur when opening and closing machine doors. The apparatus of the present invention also facilitates the incorporation of multiple bead inlets and water spray nozzles in the washing machine housing, as required.
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.

Claims

1. An apparatus for use in the cleaning of soiled substrates, said apparatus comprising housing means comprising:

(a) a stationary member;

(b) a rotatably mounted cylindrical cage; and

(c) access means,

wherein said stationary member comprises an annular planar member which is of greater internal diameter than said access means and is located adjacent said rotatably mounted cylindrical cage and said stationary member comprises a multiplicity of delivery means which are mounted thereon and a multiplicity of orifices which are respectively operably connected to said multiplicity of delivery means, wherein said multiplicity of delivery means is adapted to facilitate the delivery of materials into said rotatably mounted cylindrical cage.

2. An apparatus as claimed in claim 1 wherein said stationary member is comprised in said housing means and attached thereto by attachment means incorporating fixing members.

3. An apparatus as claimed in claim 1 wherein said stationary member is intrinsically comprised as part of said housing means.

4. An apparatus as claimed in claim 1, 2 or 3 wherein said stationary member comprises a metallic member.

5. An apparatus as claimed in claim 4 wherein said stationary member is formed of steel.

6. An apparatus as claimed in claim 4 or 5 wherein said stationary member is formed by pressing, machining, or other suitable fabrication process.

7. An apparatus as claimed in claim 1, 2 or 3 wherein said stationary member comprises a plastic member.

8. An apparatus as claimed in claim 7 wherein said member is formed by moulding.

9. An apparatus as claimed in any one of claims 1 to 8 wherein the edges of said stationary member are smoothed.

10. An apparatus as claimed in any preceding claim wherein the gap around the circumference between said stationary member and said rotatably mounted cylindrical cage is in the region of from 1-25 mm

11. An apparatus as claimed in claim 10 wherein said gap is in the region of from 3-5 mm.

12. An apparatus as claimed in any preceding claim wherein said access means may be closed so as to provide a substantially sealed system.

13. An apparatus as claimed in any preceding claim wherein said access means comprises at least one hinged door mounted in the housing means.

14. An apparatus as claimed in any preceding claim wherein said rotatably mounted cylindrical cage is mounted essentially horizontally within said housing means.

15. An apparatus as claimed in any preceding claim wherein no more than 50%, of the side walls of said rotatably mounted cylindrical cage comprises perforations.

16. An apparatus as claimed in any preceding claim wherein said perforations have a diameter of from 2 to 25 mm.

17. An apparatus as claimed in any preceding claim wherein said rotatably mounted cylindrical cage has a capacity in the region of 10 to 7000 litres.

18. An apparatus as claimed in any preceding claim wherein said cage comprises a cylinder with a diameter in the region of 75 to 120 cm.

19. An apparatus as claimed in any preceding claim wherein said cage has a length of between 40 and 100 cm.

20. An apparatus as claimed in any preceding claim wherein rotation of said rotatably mounted cylindrical cage is effected by use of drive means.

21. An apparatus as claimed in claim 20 wherein said drive means comprises electrical drive means and said electrical drive means optionally comprises an electric motor.

22. An apparatus as claimed in claim 20 or 21 wherein operation of said drive means is effected by control means.

23. An apparatus as claimed in any preceding claim which comprises circulation means.

24. An apparatus as claimed in claim 23 wherein the inner surface of the cylindrical side walls of said rotatably mounted cylindrical cage comprises circulation means comprising a multiplicity of spaced apart elongated protrusions affixed essentially perpendicularly to said inner surface.

25. An apparatus as claimed in claim 24 wherein said protrusions additionally comprise air amplifiers.

26. An apparatus as claimed in claim 25 wherein said air amplifiers are driven pneumatically and are adapted so as to promote circulation of a current of air within said cage.

27. An apparatus as claimed in claim 25 or 26 which comprises from 3 to 10 of said protrusions.

28. An apparatus as claimed in any preceding claim which comprises additional agitating means, and wherein said additional agitating means optionally comprises an air jet.

29. An apparatus as claimed in any preceding claim wherein said rotatably mounted cylindrical cage is mounted in a first upper chamber of said housing means and said apparatus additionally comprises a second lower chamber located beneath said cylindrical cage.

30. An apparatus as claimed in any preceding claim which comprises at least one recirculation means and/or pumping means.

31. An apparatus as claimed in any preceding claim which comprises housing means comprising:

(a) a first upper chamber having mounted therein a rotatably mounted cylindrical cage and a stationary member;

(b) a second lower chamber located beneath said cylindrical cage;

(c) at least one recirculation means;

(d) access means;

(e) pumping means; and

(f) a multiplicity of delivery means,

wherein said stationary member is located adjacent said rotatably mounted cylindrical cage wherein said stationary member comprises an annular planar member which is of greater internal diameter than said access means and is located adjacent said rotatably mounted cylindrical cage and said stationary member comprises a multiplicity of delivery means which are mounted thereon and a multiplicity of orifices which are respectively operably connected to said multiplicity of delivery means, wherein said multiplicity of delivery means is adapted to facilitate the delivery of materials into said rotatably mounted cylindrical cage.

32. An apparatus as claimed in claim 31 wherein said second lower chamber functions as a collection chamber for cleaning media and comprises an enlarged sump.

33. An apparatus as claimed in claim 31 or 32 wherein said at least one recirculation means facilitates recirculation of said solid particulate material from said lower chamber to said rotatably mounted cylindrical cage, for re-use in cleaning operations and comprises ducting connecting said second chamber and said rotatably mounted cylindrical cage.

34. An apparatus as claimed in claim 33 wherein said ducting comprises separating means for separating said solid particulate material from water.

35. An apparatus as claimed in claim 34 wherein said separating means comprises a vessel located above said cylindrical cage.

36. An apparatus as claimed in claim 35 wherein said vessel comprises a filter material, and said filter material optionally comprises a wire mesh.

37. An apparatus as claimed in any one of claims 31 to 36 wherein at least one recirculation means comprises first recirculation means which comprises pumping means.

38. An apparatus as claimed in any one of claims 31 to 37 which includes a second recirculation means.

39. An apparatus as claimed in claim 38 wherein said second recirculation means allows for the return of water separated by said separating means to said lower chamber.

40. An apparatus as claimed in any one of claims 15 to 39 wherein said lower chamber comprises additional pumping means to promote circulation and mixing of the contents thereof.

41. A method for cleaning a soiled substrate, said method comprising the treatment of the substrate with a formulation comprising solid particulate cleaning material and wash water, wherein said method is carried out in an apparatus according to any one of claims 1 to 40.

42. A method for cleaning a soiled substrate, said method comprising the steps of:

(a) introducing a solid particulate cleaning material and water into the second chamber of an apparatus as claimed in any one of claims 1 to 40;

(b) agitating and heating said solid particulate cleaning material and water;

(c) loading at least one soiled substrate into said rotatably mounted cylindrical cage via access means;

(d) closing the access means so as to provide a substantially sealed system;

(e) causing the rotatably mounted cylindrical cage to rotate whilst introducing said wash water and any required additional cleaning agent to uniformly wet out the substrate;

(f) introducing said solid particulate cleaning material into said rotatably mounted cylindrical cage and operating the apparatus for a wash cycle, wherein said rotatably mounted cylindrical cage continues to rotate, and wherein fluids and solid particulate cleaning material are caused to fall through perforations in said rotatably mounted cylindrical cage into said second chamber in a controlled manner;

(g) operating pumping means so as to transfer fresh solid particulate cleaning material and recycle used solid particulate cleaning material to separating means;

(h) adding said fresh and recycled solid particulate cleaning material to said rotatably mounted cylindrical cage in a controlled manner; and

(i) continuing with steps (f), (g) and (h) as required to effect cleaning of the soiled substrate.

43. A method as claimed in claim 41 or 42 which additionally comprises a rinsing operation wherein additional water is added to said rotatably mounted cylindrical cage.

44. A method as claimed in claim 43 wherein the rotation speed of said rotatably mounted cylindrical cage is increased during said rinsing operation.

45. A method as claimed in claim 43 or 44 wherein substrate treatment agents are added to the rinse water during said rinsing operation.

46. A method as claimed in claim 45 wherein said substrate treatment agents are selected from anti-redeposition additives, optical brighteners, perfumes, softeners and starch.

47. A method as claimed in any one of claims 41 to 46 wherein at least one additional cleaning agent is added to said apparatus.

48. A method as claimed in claim 47 wherein said at least one additional cleaning agent is added to the lower chamber of said apparatus with said solid particulate cleaning material, heated to the desired temperature therein, and the introduced, via said first recirculation means, into said cylindrical cage via said multiplicity of delivery means and said stationary member.

49. A method as claimed in claim 47 wherein said at least one additional cleaning agent is pre-mixed with water and added to said cylindrical cage via said multiplicity of delivery means attached to said stationary member.

50. A method as claimed in claim 47, 48 or 49 wherein said at least one additional cleaning agent comprises at least one detergent composition.

51. A method as claimed in claim 50 wherein said at least one detergent composition comprises cleaning components and post-treatment components.

52. A method as claimed in claim 51 wherein said cleaning components comprise surfactants, enzymes and bleach.

53. A method as claimed in claim 51 or 52 wherein said post-treatment components comprise anti-redeposition additives, perfumes and optical brighteners.

54. A method as claimed in any one of claims 50 to 53 which additionally comprises at least one other additive selected from 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 pigments.

55. A method as claimed in any one of claims 41 to 54 wherein, during the wash cycle, rotation of said rotatably mounted cylindrical cage is caused to occur at a G force of less than 1.

56. A method as claimed in any one of claims 41 to 55 wherein, on completion of the wash cycle, feeding of solid particulate cleaning material into said rotatably mounted cylindrical cage ceases and the G force on the cage is increased in order to effect a measure of drying of the cleaned substrate.

57. A method as claimed in claim 56 wherein said G force is between 10 and 1000.

58. A method as claimed in claim 56 or 57 wherein G force is subsequently reduced to below 1 so as to allow for removal of the solid particulate cleaning material.

59. A method as claimed in any one of claims 41 to 58 wherein said solid particulate cleaning material is subjected to a cleaning operation in said lower chamber by sluicing said chamber with clean water.

60. A method as claimed in any one of claims 48 to 58 wherein said solid particulate cleaning material is subjected to a cleaning operation in said rotatably mounted cylindrical cage.

61. A method as claimed in claim 59 or 60 wherein said cleaning operation is carried out in the presence of a cleaning agent.

62. A method as claimed in any one of claims 41 to 61 wherein said at least one soiled substrate comprises at least one textile fibre garment.

63. A method as claimed in any one of claims 41 to 62 wherein said solid particulate cleaning material comprises a multiplicity of polymeric particles and said polymeric particles optionally comprise particles of polyamides, polyesters, polyalkenes or polyurethanes or their copolymers.

64. A method as claimed in claim 63 wherein said polyamide particles comprise nylon beads.

65. A method as claimed in claim 63 wherein said polyester particles comprise polyethylene terephthalate or polybutylene terephthalate beads.

66. A method as claimed in claim 63 wherein said polyalkene particles comprise polyethylene or polypropylene beads.

67. A method as claimed in claim 63 wherein said polyurethane particles comprise beads of foamed or unfoamed polyurethane.

68. A method as claimed in any one of claims 63 to 67 wherein said polymeric particles comprise crosslinked or uncrosslinked polymers.

69. A method as claimed in any one of claims 41 to 68 wherein said washing treatment is carried out so as to achieve a wash water to substrate ratio of between 2.5:1 to 0.1:1 w/w.

70. A method as claimed in any one of claims 41 to 69 wherein the ratio of solid particulate cleaning material to substrate is in the range of from 0.1:1 to 10:1 w/w.

71. A method as claimed in any one of claims 41 to 70 wherein the wash cycle is performed at temperatures of between 5 and 95° C.

72. A method as claimed in any one of claims 41 to 71 wherein the wash cycle is performed for a duration of between 5 and 120 minutes.

73. A method as claimed in any one of claims 41 to 72 wherein the cycle for removal of solid particulate material is performed at room temperature.

74. A method as claimed in any one of claims 41 to 73 wherein the cycle for removal of solid particulate material is performed for cycle times of between 2 and 30 minutes.

75. A method as claimed in any one of claims 41 to 74 which additionally comprises separation and recovery of said solid particulate cleaning material and its re-use in subsequent washes.

76. An apparatus as claimed in any one of claims 1 to 40 for use in small or large scale batchwise processes.

77. A method as claimed in any one of claims 41 to 75 for use in small or large scale batchwise processes.