The present invention relates to a cleaning machine, and especially a cleaning machine for removing chewing gum.

Many people discard used chewing gum onto the ground, e.g. onto pavements or roads. The chewing gum turns into a hard lump which is unsightly and difficult to remove.

Special equipment such as electric or fuel driven industrial steam cleaners are often used to remove old gum, but these industrial cleaners are large and require large generators or electric cable to power them, and operation of these cleaners needs to be done when no pedestrians are about as their use can be dangerous. Often in public places such as shopping centres, the cleaning needs to be done only after all pedestrians are evacuated at night. This leads to inconvenience and expense.

The present invention seeks to provide a compact cleaner which can be operated preferably using low voltage power.

According to the present invention there is provided a cleaning machine comprising:

a) a housing with a vaporising chamber with an inlet port and an exit port,

b) at least one heating element in the vaporising chamber to vaporise liquid in the vaporising chamber, c) a supply of cleaning fluid,

d) delivery means to deliver cleaning fluid to be vaporised into the inlet port, and

e) cleaning nozzle connected to the exit port through which fluid vaporised in the vaporising chamber can pass and clean waste material.

Preferably cleaning fluid is pressurised between the supply of cleaning fluid and the delivery means.

Preferably the delivery means is an injector delivering a predetermined dose of cleaning fluid into the vaporising chamber. Preferably cleaning fluid is pressurised between the supply of cleaning fluid and the delivery means. Preferably the delivery means delivers a predetermined dose of cleaning fluid into the vaporising chamber at predetermined time intervals. Preferably the time intervals are provided by a circuit driving the injector. Preferably the delivery means delivers 0.1-1.0 ml of fluid 2 to 5 times a second.

Preferably the or each heating element is a heated electrode, e .g a glow plug. Preferably the glow plug is a diesel engine glow plug. In one embodiment there are four glow plugs.

Preferably the cleaning machine is powered by a rechargeable battery. The battery may deliver 75volts or less, e.g. 12 or 24volts. Preferably cleaning nozzle is connected to the exit port through a flexible tube. Preferably the cleaning machine has wheels to make it portable.

Preferably the cleaning machine is designed to remove chewing gum and the cleaning fluid is a sugar surfactant which destroys chewing gum leaving a powder residue that can be brushed away.

An embodiment of the invention will now be described with reference to the accompanying drawing showing a schematic view of a mach ine.

Referring to the drawing there is shown a cleaning machine 1.

Machine 1 has an outer casing 2 on wheels 3 so that it can be wheeled around so making it portable.

Inside casing 2 is a housing 10 with a vaporising chamber 11 with an inlet port 12 and an exit port 13. Four heating elements in the form of four 12V or 24V diesel engine glow plugs

14A,14B,14C,14D are provided in the vaporising chamber 11 to vaporise liquid in the vaporising chamber.

A container 20 is provided to store a supply o cleaning fluid in the form of a sugar surfactant.

Delivery means in the form of a diesel engine injector IS is provided to deliver cleaning fluid (which has been pressurised by a pump between the container and the injector, not shown) to be vaporised into the inlet port 12. A circuit 30 drives the injector to deliver a predetermined dose of cleaning fluid at predetermined time intervals into the vaporising chamber. Preferably the injector, as controlled by the circuit, delivers .1 - 1.0ml (e.g. 0.16ml) of fluid 2 to 5 times a second (e.g. 3.5 times a second). The injector may atomise the cleaning fluid as it enters the chamber 11.

A cleaning nozzle 40 having a brush 41 around the periphery of a nozzle open end 42 is connected via a flexible tube 43 to the exit port 13 through which fluid vaporised in the vaporising chamber can pass and clean waste material.

A rechargeable battery 50 powers the glow plugs 14A,14B,14C,14D and the circuit 30 and injector 15. Battery 50 is preferably 75 Volts or under, more usually 12V or 24V. In use vaporisation of fluid in the vaporisation chamber 11 by the glow plugs causing pressure in the chamber to drive vaporised fluid out of the cleaning nozzle.

The cleaning machine is preferably designed to remove chewing gum and the cleaning fluid is a sugar surfactant which when vaporised and exits the nozzle open end 42 destroys adjacent chewing gum leaving a powder residue that can be brushed away using brush 41.

The invention may take a form different to that specifically described above.

Further modifications will be apparent to those skilled in the art without departing from the scope of the present invention.