Technical Field

[0001] The present invention relates to a roof cleaning apparatus.

Background

[0002] In many countries roofs on residential houses get covered by organic matter, such as algae or moss, which negatively affects the appearance of the houses. Further, the organic matter can accelerate the natural deterioration of the roof, leading to an increased need for roof maintenance and ultimately a costly roof replacement.

[0003] Long handled tools for pressure washing the roofs of buildings are known. Typically, these comprise elongate telescopic tubing supported by a monopod. A high pressure hose is connected to a consumer pressure washing machine and threaded through the telescopic tubing. The tubing is then rotated by an operator about a swivel connection to the monopod in order to direct the pressurised cleaning fluid over the surface of the roof.

[0004] Such telescopic pressure washing tools can be heavy and difficult to operate. Furthermore, when fully extended the telescopic tubing may be too flexible to support the weight of the cleaning head in bending. As a result of this flexibility, such tools are also limited in length and therefore cannot be used for cleaning of higher structures.

[0005] Alternatively, it is also known to pressure wash a roof using a hand-held nozzle gun from a ladder or by climbing on to the roof. However, climbing on to the roof can be dangerous and can lead to roof tile damage, while directing cleaning fluid upwards from a ladder can lead to cleaning fluid ingressing underneath the tiles, causing damp.

[0006] Another technique for cleaning building roofs is referred to as "Soft Washing", and involves using low pressure water and specialised solutions, typically containing bleach and a surfactant. Again, this technique requires the operator to climb on to the roof using a ladder, and can therefore be dangerous.

[0007] There exists a need to overcome one or more of the aforementioned

disadvantages. Summary of the invention

[0008] The present invention relates to a roof cleaning apparatus comprising a cleaning head defining a fluid conduit, the fluid conduit configured to receive cleaning fluid from a cleaning fluid source flowing in a first flow direction, the conduit redirecting the fluid so as to flow in a second flow direction different to the first flow direction and thereafter to egress the cleaning head in a fluid egress direction whereby the change of momentum occasioned upon fluid flowing in the fluid conduit creates a resultant force on the cleaning head in a direction away from the fluid egress direction, and wherein the cleaning head is configured for mounting to an elongate support pole.

[0009] Since a resultant force is produced on the cleaning head in a direction away from the fluid egress direction, the cleaning head can be supported against its own weight. The fluid egress direction may be the same as the second flow direction or it may be different to the second flow direction.

[0010] The roof cleaning apparatus of the present invention may be used with an elongate support pole, for instance, to clean an elevated surface. In particular, the roof cleaning apparatus of the present invention may be used with long reach poles of the type used for suction cleaning of guttering and downpipes. In such cases, the roof cleaning apparatus may be retrofit onto pre-existing long reach poles. Alternatively, the roof cleaning apparatus may be configured as a purpose-built long reach roof cleaning apparatus comprising its own built-in long reach support pole.

[0011] The cleaning fluid source may be provided by a mains water connection. However, the cleaning apparatus of the present invention may be used with other sources of cleaning fluid, for example a tank containing a detergent or an organic cleaning fluid such as ethanol-based cleaner. In some embodiments comprising a mains water connection a separate detergent hose may be used to draw detergent from a container. The detergent hose may connect at a downstream end to an injector which injects detergent into a jet of mains water.

[0012] Preferably, when the cleaning head is attached to the support pole, the resultant force on the cleaning head due to the change of momentum occasioned upon fluid flowing in the fluid conduit acts to counter, preferably balance, the turning moment acting on the support pole due to the weight of the pole and the roof cleaning apparatus, in use.

[0013] By countering the moment acting on the support pole due to the weight of the pole and the roof cleaning apparatus, the cleaning head is easier for an operator to manoeuver over an elevated surface to be cleaned using a long reach support pole. Further, for very long poles, the stress on the pole due to the pole flexing under its own weight is reduced. This makes the pole easier to handle, and reduces a likelihood of failure of the pole.

[0014] The cleaning fluid source may be provided either internally or externally of the pole, the cleaning head being mounted to the pole. In particular, where the cleaning fluid source is provided internally of the pole, the pole itself may define a conduit. Alternatively, an additional hose could be provided internally of the pole.

[0015] Preferably, the angle between the first flow direction and the second flow direction defined by the fluid conduit is between 90° and 45°. In some embodiments, this angle may be adjustable. In particular, the angle may be adjustable between a finite number of index positions.

[0016] Providing the ability to adjust the angle between the first and second flow directions allows an operator to adjust direction of the resultant force and, optionally, the fluid egress direction to be adapted to different roof pitches.

[0017] In some embodiments of the roof cleaning apparatus of the present invention, the fluid conduit divides the cleaning fluid into two separate streams upstream of the fluid egressing the cleaning head. In particular, the two separate streams may flow in different directions to each other upstream of the fluid egressing the cleaning head. In some embodiments, the roof cleaning apparatus of the present invention may even divide the cleaning fluid into more than two separate streams upstream of the fluid egressing the cleaning head. Each of the separate streams may flow in a different direction to the others. In embodiments in which the cleaning head divides the cleaning fluid into a plurality of separate streams, the second flow direction may be defined by a resultant flow direction of the plurality of separate streams. Similarly, the fluid egress direction may also be defined by a resultant flow direction of the plurality of separate streams.

[0018] By separating the cleaning fluid into multiple streams which flow in different directions prior to egressing the cleaning head, the cleaning head is able to discharge the streams from spatially separate locations. Accordingly, the change of momentum occasioned upon each of the streams flowing in the fluid conduit will exert its own force on the cleaning head, and these forces will act on the cleaning head at spatially separated points. This improves the stability of the cleaning head and support pole to which it is attached. [0019] In preferred embodiments, the roof cleaning apparatus of the present invention may further comprise at least one nozzle through which the cleaning fluid egresses the cleaning head. This nozzle may rotate cleaning fluid flowing therethrough to produce a rotating jet of cleaning fluid. Such rotation may improve the cleaning power of the jet by utilising the rotary action to remove debris. The nozzle may also or instead be configured to spread the cleaning fluid over a range of angles as it egresses the cleaning head. For instance, the nozzle may be configured to cause the cleaning fluid to egress in a cone- shaped spray pattern. This increases the area over which the cleaning fluid impacts a surface to be cleaned, and thus can reduce the time needed to clean the entire surface. Where the nozzle is configured to spread the cleaning fluid over a range of angles as it egresses the cleaning head, the fluid egress direction may be defined by a resultant flow direction of the cleaning fluid.

[0020] Preferably, the conduit of the roof cleaning apparatus comprises an inner cleaning fluid hose which is connected to, and provides cleaning fluid to, the at least one nozzle; and an outer hose housing tube. The outer hose housing tube may be connected to a support pole to which the cleaning head is mounted, for instance by a clamp. Alternatively, other means of connecting the hose housing tube to the pole could be used, including a screw thread connection or a hose clip. The inner cleaning fluid hose may connect to an upstream hose which carries cleaning fluid from the cleaning fluid source. Any suitable water-tight connection may be used to connect an inner cleaning fluid hose of the cleaning head to an upstream hose to provide cleaning fluid from the cleaning fluid source to the nozzles. For instance, the connection may be a helical threaded connection. Alternatively, one of the hoses to be connected may have an inner diameter which is slightly larger than an outer diameter of the other of the hoses to be connected, and may be provided with grooves for O-rings which can interact with the inner surface of the larger hose in order to provide a fluid-tight seal. Further alternatively, the connection may be implemented by a simple friction fit.

[0021] In some embodiments, the at least one nozzle may be recessed into the hose housing tube in order to protect the nozzle and a surface to be cleaned in the event that the cleaning head contacts the surface. Alternatively or additionally, the roof cleaning apparatus may further comprise a cushion which is configured to protect the head and a surface to be cleaned in the event that the roof cleaning apparatus contacts the surface to be cleaned. Preferably, this cushion comprises a soft material, for example, the cushion may comprise a layer of one of a foam material and a rubber in which the at least one nozzle is encased. [0022] Preferably, the cleaning apparatus further comprises a gun, which is fluidly coupled to the fluid source and the fluid conduit of the cleaning head, and comprises a shutoff valve and a trigger which enables an operator to open and close the shutoff valve to control the flow of cleaning fluid to the conduit of the cleaning head.

[0023] Preferably, the roof cleaning apparatus further comprises a control valve which enables the flow rate of the cleaning fluid to be adjusted. Accordingly, an operator can tailor the flow rate according to the cleaning power which is required. Further, because a higher flow rate of cleaning fluid egressing the cleaning head will increase the resultant force acting on the cleaning head due to the change of momentum occasioned upon fluid flowing in the fluid conduit, the flow can also be adjusted to stabilise the cleaning apparatus and a support pole to which it is attached. For instance, a higher flow rate may be needed where the support pole is extended at a lower angle with respect to the ground, such that the turning moment acting on the pole due to the weight of the pole and the cleaning head, as well as any other components mounted thereto, is increased.

[0024] Further preferably, the roof cleaning apparatus also comprises a controller which enables an operator to adjust the flow rate of cleaning fluid via the control valve during use of the cleaning apparatus. The controller may be affixable to an item of clothing of the operator, for example a work belt. Alternatively, where the cleaning apparatus comprises a gun, as described above, the controller may be provided on the gun.

[0025] Preferably, the roof cleaning apparatus further comprises a camera mounted to the cleaning head and configured to capture images of a surface to be cleaned during use of the cleaning apparatus to clean the surface. Further preferably, this camera may be connectable to a screen by wireless connection. The screen may be mounted to a flow controller section of the cleaning apparatus, for instance a flow controller gun. Alternatively, the screen could be mounted to the long reach support pole to which the cleaning head is mounted. In this way, the operator can inspect the surface during cleaning.

Brief description of figures

[0026] The invention will now be described, by way of example only, with reference to the accompanying figures in which :

Figure 1 shows the cleaning of a roof using a first embodiment of the cleaning apparatus 10 of the present invention;

Figure 2 is a cutaway perspective view of the cleaning apparatus 10 of figure 1; Figure 3 is a cutaway perspective view of a second embodiment of the roof cleaning apparatus 10 of the present invention;

Figure 4 is a view along arrow A of figure 3;

Figure 5 is a partial perspective side view of the cleaning head 22 of the second embodiment of the cleaning apparatus 10; and

Figure 6 is a cutaway perspective view of a third embodiment of the roof cleaning apparatus 10 of the present invention.

Specific Description

[0027] Figure 1 shows an operator cleaning the roof of a residential building using a first embodiment of the roof cleaning apparatus 10 of the present invention.

[0028] Referring to figures 1 and 2, the roof cleaning apparatus 10 comprises a mains water hose 12, a consumer high pressure cleaner 14, a high pressure hose 16, a cleaning fluid hose 18, a long reach support pole 20, a cleaning head 22 and a flow controller gun 24.

[0029] In the present embodiment, the long reach pole 20 is of the type used for suction cleaning of guttering and downpipes. The long reach pole 20 may comprise any of: carbon fibre, aluminium, steel, fibreglass and a composite of carbon fibre and fibreglass.

[0030] The cleaning head 22 will be described in more detail below.

[0031] The gun 24 has a handle 26, a shutoff valve 27, shown schematically in figure 2, a trigger 28, an inline flow controller valve 29, also shown schematically in figure 2, and a control knob 30.

[0032] Referring now to figure 2, the cleaning head 22 comprises a hose housing tube 32, a flexible inner connection hose 34 and a nozzle 36. The hose housing tube 32 may comprise a lightweight material, such as any of carbon fibre, aluminium, fibreglass or a composite of carbon fibre and fibreglass. The inner connection hose 34 comprises a rubber, such as any of natural rubber, neoprene or EPDM.

[0033] The hose housing tube 32 describes a bend, such that an angle of 85° is defined between the most upstream portion thereof and the most downstream portion thereof. The connection hose 34 is flexible so that it conforms to the shape of the hose housing tube 32 such that an angle of 85° is also defined between the most upstream portion of the connection hose 34 and the most downstream portion of the connection hose 34. In figure 2 an axis system is defined, such that the support pole 20 and the upstream portion of the hose housing tube 32 and connection hose 34 extend along a direction x. The 85° bend described by the cleaning head is such that there is an angle of -5° between the axial direction of most downstream portion of the cleaning head and the -y-direction.

[0034] The nozzle 36 is a rotary nozzle. Such nozzles are well known and function to spin a jet of water exiting the nozzle to produce a rotating stream of water. Embodiments of the cleaning apparatus 10 may comprise rotary turbo nozzles which spin the water jet at a speed of between 1800 and 3000 rotations per minute. Other types of nozzle, for instance those which do not rotate fluid flowing therethrough, may be used in place of rotary nozzles.

[0035] The nozzle 36 of the first embodiment produces a cone-shaped spray pattern having an apex angle of 25 degrees. The apex angle of the cone-shaped spray pattern is not critical, however, and nozzles which produce cone-shaped spray patterns having any apex angle may be used in the cleaning apparatus 10. Alternatively, nozzles which produce a fan-shaped spray pattern, or a pencil jet (a cone-shaped spray pattern having an apex angle of 0 degrees), may be used.

[0036] The hose housing tube 32 is connected to the support pole 20 by a clamp 38. The connection hose 34 is inserted inside the hose housing tube 32 and connects at its upstream end to the cleaning fluid hose 18 via a fluid-tight helical threaded connection. The connection hose 34 is then connected to the nozzle 36 via a fluid-tight connection. In the first embodiment of the cleaning apparatus 10, the nozzle 36 is recessed within the hose housing tube 32, to protect the nozzle and a surface to be cleaned in the event that the cleaning head 22 contacts the surface.

[0037] Referring again to figures 1 and 2, the operation of the cleaning apparatus 10 will now be described. Mains water is carried to the high pressure cleaner 14 through the mains water hose 12 where the high pressure pump creates a high pressure jet. The high pressure jet is then delivered to the inline flow controller valve in the gun 24 by high pressure hose 16, and thereafter passes through the cleaning fluid hose 18 and the connection hose 34 of the cleaning head 22 to egress through the nozzle 36 in a rotating stream having a cone-shaped spray pattern.

[0038] As the fluid flows around the bend defined by the hose housing tube 32 and connection hose 34, there is a decrease in momentum along the x-direction and an increase in momentum along the -y-direction. This causes a reaction force F, which has components which act along the +x-direction and along the +y-direction, to be exerted on the cleaning head 22. The nozzle 36 acts to decrease the component of the reaction force acting along the +y-direction. The reaction force F exerts a turning moment on the support pole 20 which balances the turning moment due to the weight of the cleaning head 22 and the support pole's own weight, such that the cleaning head 22 hovers above the roof.

[0039] As can be appreciated by those skilled in the art, the hovering effect of the cleaning apparatus 10 of the present invention reduces the length constraint on long reach roof cleaners of the type described, enabling longer poles to be used and much higher surfaces to be cleaned by an operator who is standing on the ground.

[0040] Further, because the support pole 20 and cleaning head 22 are supported against their own weights, the ease of handling of the cleaning apparatus 10 is improved. In the present embodiment the operator is able to easily move the cleaning head 22 over the roof to achieve an effective clean by holding on to the handle 26 of the gun 24. The inclusion of the inline flow controller valve 29 in the gun allows the operator to control the water flow to the gun 24 by turning the control knob 30. Accordingly, the operator is able to tailor the downward pressure that manipulates the hover effect and cleaning impact.

[0041] Referring now to figures 3, 4 and 5, the second embodiment of the cleaning apparatus 10 is substantially similar to the first embodiment, and like reference numerals are used to denote like features. The cleaning head 22 of the second embodiment is, however, distinguished from that of the first in that it defines two separate branches 22a and 22b, whereby the connection hose 34 and the hose housing tube 32 of the second embodiment of the cleaning apparatus 10 each divide into two oppositely directed branches 34a, 34b and 32a, 32b, respectively. A respective nozzle 36a, 36b is connected to the downstream end of each branch of the connection hose 34a, 34b. As described in connection with the first embodiment, the nozzles 36a, 36b are recessed within a respective branch of the hose housing tube 32a, 32b so as to create an air space of approximately 100 mm between the tip of the nozzle 36a, 36b and the downstream end of the hose housing tube 32a, 32b. This prevents the nozzle 36a, 36b from contacting the roof tile, in the event that the cleaning head 22 contacts the roof tile.

[0042] The most downstream portions of the branches of the hose housing tube 32a, 32b and connection hose 34a, 34b are parallel to each other and each define an angle of 90° with the support pole 20 in the x-y plane. [0043] The operation of the second embodiment of the cleaning head is substantially similar to that described in connection with the first. It differs, however, in that the cleaning fluid is divided into two separate streams as it flows through the cleaning head 22. At the bifurcation of the cleaning head 22 the streams are directed in opposing directions. With respect to the axis system of figure 4, cleaning fluid flowing through the branch 22a of the cleaning head gains momentum in the -z-direction, and cleaning fluid flowing through the branch 22b of the cleaning head gains momentum in the +z-direction. As a result, a reaction force f _yåb is exerted on the branch 22b of the cleaning head, and a reaction force f _yza is exerted on the branch 22a of the cleaning head. If the flow rates of the two separate streams are the same, the z-components of the reaction forces f _yza and f _yZb will cancel, such that the resultant reaction force F has no component in the z- direction.

[0044] In the second embodiment of the cleaning apparatus 10, a camera 40 is provided on the cleaning head 22. The weight of the camera 40 is also supported by a reaction force F on the cleaning apparatus 10 caused by the acceleration of the high pressure jets on leaving the nozzles 36a, 36b. The operator is able to inspect the cleanliness of the roof by viewing the roof from the screen 42.

[0045] Referring now to figure 6, a third embodiment of the cleaning apparatus 10 of the present invention is configured as a purpose-built long reach roof cleaning apparatus 10, and comprises: a mains water hose 12, a consumer high pressure cleaner 14, a high pressure hose 16, a pipe 44, two nozzles 36a, 36b and a gun 24. Components of the third embodiment of the roof cleaning apparatus 10 upstream of the pipe 44 are substantially the same as those already described in connection with figures 1-5, and will not be described.

[0046] The pipe 44 provides a rigid structure to support the nozzles 36a, 36b above the ground, whilst also directly containing the cleaning fluid and acting as a conduit therefor. The pipe 44 of the second embodiment, therefore advantageously comprises a corrosion resistant material such as a metal, for example stainless steel or copper, or a polymer such as PVC or PTFE.

[0047] The pipe 44 is substantially linear over most of its length but bends at its downstream end so as to describe a bend which defines an angle of approximately 85° between its upstream and downstream ends. The pipe 44 also splits into two lateral branches 44a, 44b. [0048] A respective one of the nozzles 36a, 36b is connected at the downstream end of each of the lateral branches 44a, 44b.

[0049] The operation of the third embodiment of cleaning apparatus 10 is substantially the same as that described in connection with the second embodiment. However, in the third embodiment, the pipe 44 acts as both the supporting structure and the fluid conduit which delivers fluid to the nozzles. In other words, unlike in the first and second embodiments, in the third embodiment, the cleaning fluid is directly contained by the walls of the pipe 44, rather than an additional internal hose.