LIQUID DISPENSING APPARATUS

Abstract

A portable liquid dispensing apparatus is described, which comprises a battery, a heating element, a liquid reservoir, a pump, an outlet, and a pipe, extending from the reservoir to the outlet and passing adjacent the heating element. In operation, the pump drives liquid from the reservoir into and through the pipe while the power source causes the heating element to heat the liquid passing through the portion of the pipe adjacent to the heating element to be expelled from the outlet at a temperature greater than the ambient temperature.

Claims

1. A portable liquid dispensing apparatus, comprising: a battery; a heating element; a liquid reservoir; a pump; an outlet; and a pipe, extending from the liquid reservoir to the outlet and passing adjacent to the heating element; wherein, in operation, the pump drives liquid from the reservoir into and through the pipe while the power source causes the heating element to heat the liquid passing through the portion of the pipe adjacent to the heating element to be expelled from the outlet as a heated liquid at a temperature greater than the ambient temperature.

2. The portable liquid dispensing apparatus according to claim 1, wherein the liquid is heated to a temperature at least 40 degrees Centigrade.

3. The portable liquid dispensing apparatus according to claim 1, wherein the temperature of the heated liquid is controlled via the pump.

4. The portable liquid dispensing apparatus according to claim 1, 2, wherein the temperature of the heated liquid is controlled via a diameter of the pipe.

5. The portable liquid dispensing apparatus according to claim 1, 2, wherein the temperature of the heated liquid is controlled via a voltage of the battery.

6. The portable liquid dispensing apparatus according to claim 1, wherein the portion of the pipe passing adjacent to the heating element is coiled around the heating element.

7. The portable liquid dispensing apparatus according to claim 1, wherein the heating element is proximate the outlet.

8. The portable liquid dispensing apparatus according to claim 1, further comprising a housing, wherein the power source is contained within or mounted onto the housing.

9. The portable liquid dispensing apparatus according to claim 6, wherein the pipe is coiled around a second heating element.

10. The portable liquid dispensing apparatus according to claim 9, wherein the pipe is coiled around the heating element and the second heating element individually to form a coiled heating unit, and wherein the pipe is further coiled around the coiled heating unit.

11. The portable liquid dispensing apparatus according to claim 1, wherein the heating element and the portion of the pipe adjacent to the heating element are mounted within a heat insulating material.

12. The portable liquid dispensing apparatus according to claim 1, wherein the liquid comprises water.

13. The portable liquid dispensing apparatus according to claim 1, wherein the liquid comprises a chemical.

14. The portable liquid dispensing apparatus according to claim 1, further comprising a brush, wherein the outlet dispenses the liquid through or adjacent to the brush.

15. The portable liquid dispensing apparatus according to claim 9, wherein the pipe is a copper pipe.

16. The portable liquid dispensing apparatus according to claim 15, wherein the copper pipe has an inner diameter of approximately 1 mm.

17. The portable liquid dispensing apparatus according to claim 15, wherein the copper pipe has an outer diameter of approximately 2 mm.

18. The portable liquid dispensing apparatus according to claim 15, wherein the pump is operable to drive liquid from the reservoir at a rate of approximately 22 ml per minute.

19. (canceled)

Description

DETAILED DESCRIPTION

[0033] The invention will now be described by way of example with reference to the following Figures in which:

[0034] FIG. 1 schematically illustrates a gum removal apparatus; and

[0035] FIGS. 2A and 2B schematically illustrate a heated liquid generating unit for the apparatus of FIG. 1.

[0036] FIG. 3 schematically illustrates an alternative heated liquid generating unit

[0037] FIG. 4 schematically illustrates the heated liquid generating unit of FIG. 3 connected to a handle

[0038] Referring first to FIG. 1, a gum removal apparatus 100 is shown schematically. The gum removal apparatus 100 is in this case a floor-based apparatus which can be moved around on wheels 105. It will be appreciated that a hand-held version could be similarly constructed. The gum removal apparatus 100 comprises a water/chemical tank 110, which in this case holds up to 2 litres of water and/or chemicals. If the apparatus is to be used for cleaning (for example) rather than gum removal, water may be used. If the apparatus is to be used for weedkilling, a weedkilling chemical may be used. For gum apparatus, any suitable known chemical for breaking down gum may be used. Preferably, such a chemical should be a non-foaming detergent formulated to not block up the relatively small pitch pipework of the apparatus. A suitable chemical may be formulated from alkyl polyglucoside (5-10% by volume), amphoteric surfactant (10-30% by volume), decyldimethylamine (<0.5% by volume), and water. A pipe or tube extends from the tank 110 to a nozzle 120, passing through a heating unit 130. The heating unit 130 comprises one or more electric heating elements which can be heated by applying electrical power from a battery unit 140 mounted into the device. The pipe coils around the heating elements in the heating unit 130, in a manner which will be described below. The heating unit 130 also comprises thermal insulation which surrounds the heating elements and the part of the pipe which coils around the heating elements. A peristaltic pump 150 with a fixed flow rate is used to drive liquid from the tank 110 through the pipe, and in particular through the heating unit 130 to be boiled, and to be dispensed/expelled from the nozzle 120. It will be appreciated that, provided the pump 150 is providing a constant flow of liquid through the heating unit 130, a relatively constant amount of heat is required to convert the liquid into hot water and/or steam/vapour at the same rate as it is driven through the heating unit 130. This is in contrast to a “boiler” based system in which the amount of heat required varies over time as the amount of liquid in the boiler reduces.

[0039] A controller 160, comprising for example a printed circuit board and on/off switch, is provided near to a handle 170 used to move the device around. At its simplest, the device 100 can have a simple on/off operation, with a fixed amount of hot water or steam being ejected through the nozzle 120 when the device is on. However, the device could have multiple settings corresponding to different volumes of hot water and/or steam/vapour being ejected through the nozzle 120. To achieve these different hot water and/or steam flow settings, an increase in liquid flow rate driven by the pump 150 is accompanied by an increase in electrical power applied to the heating elements, resulting in an increased volume of hot water and/or steam expelled from the nozzle. A correspondence between liquid flow rate and the electrical power to be applied to the heating unit 130 is defined in advance and predetermined at the apparatus - the operator is not required to directly modify the liquid flow rare or the applied electrical power in order to obtain hot water and/or steam at the nozzle 120. Towards the centre of the body of the device, a hinge 180 is provided, permitting the device to fold in half for easy transportation. It will be noted that the heating unit 130 is located proximate the nozzle, so that hot water and/or steam is generated very close to the point at which it is to be dispensed.

[0040] FIGS. 2A and 2B schematically illustrate the structure of the heating unit 130. Referring to FIG. 2A, a first 100 watt element 1 having a 3.5 mm diameter, has a coil of copper pipe 3 wound around it. The element 1 also has positive and negative terminals, to which electric power is supplied from the battery 140 in order to heat the element 1. The copper pipe 3 has an external diameter of 2 mm and an internal diameter of 1 mm. An inlet 2 to the coil of pipe 3 comes from an outer (secondary) coil 8 (shown in FIG. 2B). A continuation 4 of the pipe 3 then extends across to a second 100 watt element 5, where the pipe 3 coils around the second element 5. The second element 5 is of the same type as the first element 1, and again has positive and negative terminals, to which electric power is supplied from the battery 140. Turning to FIG. 2B, the same parts as shown in FIG. 2A are provided with the same reference numerals. In FIG. 2B, the outer (secondary) coil 8 is shown to coil around the FIG. 1 arrangement of heating elements 1, 5 and coil 3, and to be a continuation of the pipe 3 (via the inlet 2). Liquid enters the outer (secondary) coil 8 via an inlet feed 7 from the pump 150 and tank 110. The liquid then progresses first through the outer coil 8, and then into the primary coil of pipe 3 via the inlet 2. The liquid then progresses through the pipe 3 travelling adjacent to the first element 1 and then the second element 5, before eventually exiting the heating unit via a steam/vapour/hot liquid escape 6. It will be appreciated that the liquid in the feed 7 is relatively cool, but is then pre-heated as it passes around the secondary coil 8, and then heated up as it passes through the pipe 3 adjacent to the first and second elements. The heating elements and coiled pipework are housed within an insulated unit 9. Insulating the two probes and coils with a high heat resistant material 9, serves to (a) concentrate any escaping heat back onto the copper coils and (b) protect the surrounding machine parts from any heat escaping from the copper coils, making the machine cool to the touch.

[0041] It will be appreciated that this arrangement makes it possible to create heated liquid or steam via a battery power by using a set of electrical probes and copper tubes. Previously, to generate sufficient heated liquid or steam for cleaning purposes existing machines have relied on mains electricity or gas to generate enough energy to create heated liquid or steam. However, by coiling (preferably) a minimum of 1.5 metres of 2 mm outer diameter, 1 mm inner diameter copper pipe around 2×100 watt insulated metal elements or a 1×200 watt insulated metal element, along with additional pipe (secondary) to pre-heat the supply of liquid, it has been found that it is possible to generate heated liquid or steam using battery power This method allows the design of a portable machine with inbuilt batteries to allow 2-4 hours of operation (depending on the battery capacity) before recharging. The small reservoir tank 110 feeds either a unique chemical or water into 1.5 meters-4 meters of copper pipe under the influence of the peristaltic pump 150. The pump 150 is set to only allow fluid through for a constant feed (depending on the cleaning task at hand). Copper is used due to its fast transfer of heat to the liquid inside. Through testing, it has been discovered that in using a thin walled copper pipe, the liquid heats up more quickly, and it has been calculated that the amount of liquid required to remove chewing gum for this configuration of copper piping and heating elements is a flow rate (set at the pump 150) of 22 ml per minute.

[0042] The copper pipe 3 is repeatedly wound around the element 1 with a tight fit and then taken across to the second element 5 with a further continual tight-fitting coil around the second element 5. The secondary coil 8 which surrounds the two probes absorbs heat escaping from the primary coil 3, and transfers this to the liquid flowing through the secondary coil to effectively pre-heat the fluid to ensure that sufficient heated liquid or steam is emitted from the nozzle. The heated liquid or steam escapes through the escape 6 to the nozzle 120 which has a small brush attached which is used to agitate gum deposit to destroy a piece of discarded chewing gum in seconds. The method of using two coils and the above-described speed of fluid (22 ml per minute) delivery results in a device suitable primarily for use for chewing gum removal. It has also been found that the same result can be achieved by using a single 200 watt element with the same copper pipe coiled around and insulated with the heat resistant material. Two 12-volt batteries with an 8 amp output may be used to provide for at least 2 hours of continuous operation before a re-charge of the batteries is required.

[0043] By changing the configuration of batteries, heating elements and fluid delivery, there are numerous other uses including the removal of stickers and sticky adhesive residue, chemical free grout cleaning, chemical free general heated liquid or steam cleaning and chemical free weed killing. The device described with reference to FIGS. 1 and 2 is constructed for floor cleaning, however the same technology can also be used in a hand held device to clean vertical surfaces such as grout between wall tiles and also the removal of unwanted stickers and adhesive residues which is ever growing problem. A hand held device may allow chewing gum removal from difficult to reach places such as on top of and under seats in public places and on public transport or from under surfaces such as school tables, train tables and other difficult to clean places, where chewing gum is discarded as well as from all urban and carpeted surfaces.

[0044] FIG. 3 schematically illustrates a heating element wherein the pipe 3 is wrapped around a single heating element 1. In this embodiment, the heating of the fluid is less than the embodiment depicted in FIGS. 2A and B due to the absence of a second heating element 5. As such, in this embodiment, there is little or no generation of steam.

[0045] In FIGS. 3 and 4 the apparatus works in a similar way to that shown in FIG. 1 excepting that the coil 3 is wrapped around a single heating element 1 and housed within the hot liquid or steam dispensing end of a portable steam or liquid dispensing apparatus 200. Advantageously this means that the weight of the coil 3 and associated apparatus is contained at the end positioned towards the surface to be cleaned rather than in a separate backpack or ‘tow-along’ apparatus. This provides easier handling by the user. The liquid to be heated is pumped through a pipe 220 and into a coil 3 before being heated and being dispensed through a nozzle 230.

[0046] Some of the advantages of the present technique are: [0047] (a) Silent operation, so it does cause noise pollution to the operator or anyone in the vicinity of the machine. [0048] (b) The machine is lightweight, making it easy to operate and eliminating the risk of injury, repetitive strains or long term ill effects to the operator. The lightweight (and folding) design also makes storage and transportation simple. [0049] (c) Inexpensive materials and methods are required, which means that the machines will cost much less than traditional machines for steam generation and chewing gum removal. The existing machines can cost many thousands of pounds for even entry-level machines and a power source is still required, which is an additional and ongoing cost. [0050] (d) Major reduction in cost of operating a steam cleaning device as a full charge to the batteries will cost a few pence rather than using gases or a petrol/diesel generator. [0051] (e) The machines are portable—eliminating or at least mitigating the requirement for the operator to wear a heavy backpack, carry a weighty hand held lance or have to manoeuvre a weighty machine and generator. There are also no trailing leads or hoses to consider. The operator will also be able to work in confined spaces, as the device is compact. [0052] (f) None of the risks associated with using gases to heat the water, or having to use electricity from a powerful generator or mains source around the presence of water. [0053] (g) The option of having a set flow rate on the device allows the operator to have a ‘plug and play’ experience. This means no need for extensive training of individual operators or associated problems of confusion over multiple machine settings. [0054] (h) Environmentally friendly operation due to the use of rechargeable batteries rather than having to use fuels such as LPG/Propane, petrol or diesel, which are not from renewable sources. [0055] (i) Safe to use in all locations as no LPG/propane or highly flammable fuel for a generator is used. This will make the cleaning process much easier in sensitive locations such as major transport hubs (particularly underground/subway stations and airports), service station forecourts (where there is an unacceptable risk to machines using an internal flame) and places where a risk assessments would prohibit the use of explosive fuels from being used.

[0056] The portable heated liquid device may also be fitted into existing or new cleaning machines to allow them to clean with heated water or other heated fluids, improving the efficiency of cleaning machines which are already in use instead of requiring existing machines to be replaced with those containing the new, heating component.