PRESSURE WASHER APPARATUS

Abstract

The present invention relates to hand held apparatus which is for use in the provision of a supply of a liquid, such as water, which is emitted from the apparatus at a pressure which is greater than that at which it enters the apparatus and which apparatus is commonly referred to as a pressure washer. The invention is particularly, although not solely, related to the provision of the apparatus with a power supply which is mounted on the same and therefore renders the apparatus completely portable and the apparatus is provided with a pump, operating control means and features which allow a greater pressure of the liquid that is emitted to be achieved than is possible with conventional battery powered pressure water apparatus.

Claims

1. Pressure washer apparatus, said apparatus including an input for connection to a source of a liquid, an output from which the said liquid leaves the apparatus, when operating, at a pressure greater than that which it enters the apparatus, a power supply to the said apparatus to operate a motor and in turn operate a pump, said pump located intermediate the said input and output and through which the liquid passes and wherein said pump includes a plurality of pump assemblies which are angularly offset about a drive axis.

2. Apparatus according to claim 1 wherein each of the pump assemblies includes a plunger mechanism provided for linear movement along a respective axis and the axes of the respective plunger assemblies are substantially perpendicular to the axis of a channel along which the liquid flows from the pump to the output.

3. (canceled)

4. Apparatus according to claim 1 wherein each pump assembly includes an inlet check valve so as to allow liquid to enter from a common chamber which is supplied with liquid from the said input and an outlet check valve to allow leave and be combined downstream of the outlet valves, and pass along at least one channel to the output of the apparatus.

5-7. (canceled)

8. Apparatus according to claim 1 wherein there is provided a rotatable drive shaft mounted along the said drive axis and driven to rotate by the motor which is provided in the housing and connected to said power supply a drive member including a track is provided which has a centre which is offset to the said drive axis and about which drive axis the drive member rotates so as to move the said plunger mechanisms of the respective assemblies in a sequential manner.

9. (canceled)

10. Apparatus according to claim 1 wherein the motor, pump, input and output are all located within a common housing which includes at least one power supply means connected therewith and the said power supply means are selectively locatable with the housing and carried thereby during operation of the apparatus.

11-12. (canceled)

13. Apparatus according to claim 1 wherein the source of liquid supply is a container in which water is held or a mains water supply and/or a source for a cleaning media to be added to the water.

14. (canceled)

15. Apparatus according to claim 1 wherein the pump includes an inlet chamber and an outlet chamber, a chamber communicating the inlet chamber and the outlet chamber, each pump assembly including an inlet valve connected to the inlet chamber, an outlet valve connected to the outlet chamber and a plunger mechanism, and a drive member located on the drive axis, said drive member including an eccentrically mounted track such that when the drive member rotates the track pushes the plunger mechanisms individually and in sequence away from the drive axis and returns the plunger mechanisms individually and in sequence via a bearing located with the track.

16. Apparatus according to claim 15 wherein in each pump assembly the outlet valve is driven by the inner engaging wall of the drive member while the inlet valves are driven by the respective plunger mechanism and the eccentric outer ring.

17. Apparatus according to claim 15 wherein the plunger mechanisms are provided with at least one bearing located in the track of the drive member so as to move in an eccentric path with respect to the drive axis.

18: Apparatus according to claim 17 wherein the plunger assemblies are in contact with the eccentric member track via one or more rotatable bearings and each plunger mechanism is provided with a contact slot connected with the eccentric moving cup.

19. Apparatus according to claim 1 wherein the plunger mechanism consists of at least two different materials in order to adjust the weight of the plunger mechanisms to reduce overall vibration of the apparatus.

20. (canceled)

21. Apparatus according to claim 15 wherein the outlet chamber is connected to a pressure valve which prevents liquid from flowing through the apparatus when the pump is not activated.

22. Apparatus according to claim 1 wherein the motor connected to the drive shaft is selectively operable at different speeds to regulate the pressure and the flow of liquid from the outlet of the pump.

23. Apparatus according to claim 15 wherein the pump assembly is suspended from the inner walls of the housing so as to dampen vibration caused by operation of the pump.

24. (canceled)

25. Apparatus according to claim 1 wherein there is provided a component intermediate the motor and the pump to pass at least a portion of the input liquid past the motor to provide a cooling effect on the motor during operation of the apparatus.

26. Apparatus according to claim 1 wherein the apparatus includes a user actuable means to allow the selective change of the apparatus between on and off conditions and wherein at least one check valve assembly is provided in the flow path of the liquid between the input and the output and the operation of the check valve assembly between closed and open positions is achieved by the movement of control means between first and second positions.

27-28. (canceled)

29. Apparatus according to claim 26 wherein the control means are connected to a member of the check valve assembly which exerts a movement force on a valve seat of the check valve to move the same to an open position when the control means is moved to the second position.

30. Apparatus according to any of the claim 26 wherein the check valve includes biasing means which, when the control means is moved from the second position, causes the valve seat to be returned to a closed position automatically and without the need for user actuation of the control means.

31. Apparatus according to claim 26 wherein the valve seat and control means are arranged so that the valve seat is moved to the open position when the control means is moved to a second position in which the same also acts to lock the user actuation means.

32. Apparatus according to claim 26 wherein when the user actuation means are in the on condition and the check valve is in the open position the motor and pump are operated to pressurise the said liquid before it leaves the output.

33. (canceled)

34. Apparatus according to any of the claim 26 wherein the control means includes a portion which is located with respect to the user actuation means so that when the control means is moved to a locking position the user actuation means is retained in position.

35. Apparatus according to claim 1 wherein the apparatus includes temperature sensing means to detect the temperature of the liquid at the input, means to communicate data relating to said temperature to control means for the operation of the apparatus, a database which links the viscosity of the liquid to the detected temperature and adjustment means to adjust the speed of the motor and/or pump to thereby control the pressure of the liquid emitted from the output of the apparatus.

36. (canceled)

37. Apparatus according to claim 1 wherein the voltage of the power source is monitored during operation of the apparatus and as the voltage level drops the speed of operation of the motor is adjusted so as to maintain a substantially uniform speed of operation of the pump and hence pressure of liquid from the output.

38. Pressure washer apparatus including a housing in which there is provided a pump which includes an inlet chamber into which a liquid is supplied and an outlet chamber, a chamber communicating the inlet chamber and the outlet chamber, a plurality of pump assemblies, each said pump assembly including an inlet valve connected to the inlet chamber, an outlet valve connected to the outlet chamber and a plunger mechanism, a drive member located on a drive axis, said drive member including an eccentrically mounted track such that when the drive member rotates the track pushes the plunger mechanisms individually and in sequence away from the drive axis and returns the plunger mechanisms individually and in sequence via a bearing located with the track so as to operate the said pump assemblies in sequence and create an output of liquid at a greater pressure when emitted from an output of said apparatus than when the said liquid is supplied into the inlet chamber.

Description

[0049] Specific examples of the invention are now described with reference to the accompanying drawings wherein:

[0050] FIG. 1 illustrates apparatus in accordance with one embodiment of the invention;

[0051] FIGS. 2a-l illustrate the stages of operation of a pump provided with apparatus in accordance with one embodiment of the invention;

[0052] FIGS. 3a and b illustrate two embodiments of the provision of bearings for the plunger mechanisms;

[0053] FIGS. 4a-i illustrates a shuttle member of the check valves in one embodiment;

[0054] FIG. 5 illustrates schematically the relationship between the motor shaft, the pump housing and the rotatable pump components.

[0055] FIG. 6 illustrates a pressure washer apparatus in accordance with one embodiment of the invention;

[0056] FIG. 7 illustrates in a schematic manner, the flow path of the liquid through the apparatus of FIG. 1;

[0057] FIGS. 8a and b illustrate a check valve locking means assembly in accordance with one embodiment of the invention; and

[0058] FIG. 9 illustrates the manner in which the dynamic viscosity and density of water changes with respect to changes in temperature.

[0059] Referring now to FIG. 1, there is illustrated apparatus in accordance with an embodiment of the invention in which the same is provided as a portable pressure washer apparatus 2. The apparatus comprises a housing 4 which has an input 6 and leads to a lance portion 7 which has an output 8. The input 6 is provided to be connected to a source of liquid such as water and, in this embodiment, the connection with the source is via a standard hosepipe connection but it should be appreciated that other forms of input can be provided to suit the particular source from which the water is provided. For example, rather than a hosepipe being the source via which mains water is delivered to the apparatus, the water may be provided in a container fitted to the housing 4 and or is connected to the housing by a pipe to allow water to be drawn from the container and into the input 6.

[0060] At the output 8, there may be provided means 9 to allow the user to adjust the particular form in which the liquid is output such as, for example, a selection can be made between providing the output of the water in the form of a spray, a single stream or variations of the same.

[0061] Also provided in the housing are mechanical engagement means 10 which are provided to allow the mechanical engagement with the housing of a battery pack 12 as shown. The battery pack can be of any appropriate form and, is provided with, typically in a conventional manner, a series of terminals which, when the battery pack is mechanically engaged with the housing, electrical contact is made with terminals provided on the housing.

[0062] When the power cells and the battery pack are charged and the battery pack is mechanically connected to the housing, so power for operation of the apparatus is provided from the battery pack. Also provided on the housing are switching means 14 to allow the switching on and off of the apparatus as appropriate and this allows the generation of the output of water at a higher pressure than that at which it enters the apparatus. In order to allow the water to exit the output 8, the user operates a trigger switch 16 which is selectively operable by the user so as to allow the output of water under pressure and the user can grip the housing via the handle 18 and then direct the output of water towards a particular article or surface so as, for example, to perform a cleaning operation on the same.

[0063] Within the housing, there is provided a motor 20 shown in broken lines which is connected to the power source and which operates so as to allow the operation of a pump 22 also provided within the housing and again shown in broken lines. The pump, when operated by the motor, allows the movement of water from the input 6 to the output 8 and when passing through the pump located intermediate those two locations, the pressure of the water is increased. Some or all of the water which enters the apparatus from the input 6, may be directed in a path around the motor 20 so as to create a cooling effect on the motor as it operates.

[0064] Turning now to FIGS. 2a-l, there is illustrated the steps of operation of the pump of the apparatus, in accordance with one embodiment of the invention.

[0065] It will be shown that from the input of the apparatus, the water is passed, as indicated by arrow 24 into the pump as shown in FIGS. 2a-c and the pump provides a suction effect to draw the water from the supply into the assemblies as the pump cover is sealed from the external environment in the housing and the inlet is sealed off from the external environment and from the internal pump chamber 26. In the pump chamber 26, in this embodiment, there are provided three pump assemblies 28, 30,32 which are radially located around a centre axis 34 which typically, runs along the same axis as that of the rotational shaft 35 of the motor and, on which, movement control means for the three pump assemblies are mounted. It should be appreciated that in other embodiments. Each pump assembly 28,30, 32 includes an inlet check valve 36, and a connected outlet check valve 38 and which, in combination, form a path 48 for the water to pass through the pump assembly.

[0066] As shown in FIG. 2c the water from the inlet spread out to the inlet check valves 36 under the effect of the suction created by the plunger mechanisms 40 which are provided in each pump assembly and which are moveable in a reciprocating linear manner as indicated by arrows 42 so as to allow water to be drawn into the inlet check valve 36 under vacuum and exit the outlet check valve 38 under pressure. The water which leaves the outlet check valve 38 of each of the pump assemblies, as indicated by arrows 44 in FIGS. 2d and h, is then combined and passes as indicated by arrow 50 in FIG. 2i to pass to the output 8 of the apparatus to form the high-pressure water flow which is dispensed from the apparatus. FIG. 2e illustrates the manner in which the water passing out of the inlet check valve 36 and then being pushed from the pump under pressure via the outlet check valve 38.

[0067] As shown in FIG. 2f the plunger mechanisms 40 create the suction needed to pass the water through the inlet and outlet check valves of the respective pump assemblies. The plunger mechanisms are moved to their respective positions in an offset sequence. FIGS. 2k and l and FIG. 5, mounted on the rotating shaft 35 of the motor along axis 34 there is provided a drive member 52 which includes a track formed so as to be eccentrically rotatable with respect to the rotating shaft 35 and is driven to rotate by the motor shaft within the cavity 54 of the pump and with which the pump assemblies 28,30,32 are in connection via respective bearings 60. The drive member 52 rotates along with the rotating motor shaft 35 and, as it does so, the same moves the plunger mechanisms 40 of the respective pump assemblies via engagement of the bearings 60 in the track so as to linearly move the plunger mechanism 40 of each pump assembly in a predefined sequence. Thus, at any given time, in accordance with one embodiment of the invention, one of the pump assemblies has its plunger mechanism 40 in a position so that the liquid therein is under pressure so as to emit the high-pressure water from its outlet check valve and the other two pump assemblies are under vacuum so as to draw water from the water supply to the pump into the inlet check valves of the respective assemblies and the condition of the respective pump assemblies change as the rotation of the drive member occurs so that the pump assemblies emit high pressure water therefrom in sequence This sequence of operation is repeated for each revolution of the drive means.

[0068] The drive member track has points of contact with the respective plunger mechanisms bearings 60, and the points of contact of the track are formed, similar to a cup and which has an outer ring surface 56 to push the plunger mechanisms 42 outwardly away from the shaft and an inner engagement wall 58 which engages with the said plunger mechanisms and as the track rotates, the relative position of the bearings 60 with respect to their plunger mechanism act to draw the plunger mechanisms inwardly or push the same outwardly depending on the position of the bearing on the track at that time. It will be appreciated that the shaping of the drive member 52, inner engagement wall 58, outer ring surface 56 and the degree of eccentric mounting of the drive means 52 on the shaft 35 are all selected so that in combination the same allow the required control of the sequence of operation of the respective pump assemblies and so as to provide a substantially continuous supply of higher pressure water from the respective pump assemblies and which then combine as indicated by arrows 43 of FIG. 2g to then leave from the pump as indicated by the arrow 50 as a combined pressurised flow to the outlet 8. Typically the pump includes an outer cover at the side of the pump at which the water enters and leaves the pump, as shown in FIG. 2i and which is not shown in certain other of the Figures for ease of illustration.

[0069] FIGS. 3a and b illustrate two possible bearing assemblies which can be provided at the end of the plunger mechanism 40. In FIG. 3a there is shown the end of the plunger mechanism with a recess 74 to one side of the same and in which is located the bearing 60. Alternatively and perhaps most suited to embodiments of the apparatus which are provided to allow a relatively high pressure water supply to be provided, the embodiment shown in FIG. 3b can be used in which the end of the plunger mechanism is provided with recesses 74,74′ on opposing sides of the mechanism 40 and into which recesses respective bearings 60, 60′ are located.

[0070] The movement of the valve seats within the respective inlet and outlet check valves, is as a result of the creation of the pressure and vacuum and springs can be provided to act on the seats so as to act as a failsafe mechanism should there be a malfunction and the pressure or vacuum increases beyond a certain limit. Thus, it will be appreciated that the movement of the valve seats in the inlet and the outlet check valves, are as a result of the creation of the vacuum or pressure by the plunger mechanism 40 with which the respective inlet and outlet check valves are associated and, that each assembly operates in sequence but independently from the other assemblies. The views of FIGS. 4a-i illustrate one embodiment of a valve seat 62 which is located in the inlet and outlet check valves 36, 38 and it will be seen that the seat 62 is provided with a series of legs 64 which define a cross shaped recess 66 at one side and three spaced apart leg members 68 on the opposing side of the seat. The legs 64, 68 and outer surface 70 of the seat act to guide the movement of the seat linearly along the respective check valve with the outer wall 70 contacting the inner side walls of the check valve.

[0071] With apparatus of this type there can be problems of leakage of liquid through the apparatus when the same is not being used but is still connected to the water supply and in particular a mains water supply which has some degree of pressure. In order to address this problem, in one embodiment, and typically located downstream 72 of, and in the output flow from, the pump there is provided a safety valve which is controlled to operate at a pressure above the pressure of mains water at the input. This means that when the liquid in the apparatus is not being acted upon by the operation of the pump the safety valve is shut and thereby prevents the flow of the liquid through the output of the apparatus. However when the pump is activated and the pressure of the water increases so the safety valve is opened and the pressurised water is supplied from the apparatus.

[0072] There can also be concerns with apparatus of this type which can produce relatively high pressure liquid therefrom and the potential risk to safety of users and/or bystanders due to incorrect use of the apparatus and/or unauthorised adaptation of the apparatus. In order to prevent or minimise this risk there is, in one embodiment, provided in the pressurised water output downstream 72 from the pump, a limiter assembly which in one embodiment includes a switch which is capable of operating and over riding manual control of the control means of the apparatus so as to switch off the motor and hence pump should a valve provided with the limiter assembly be closed by the pressure of the water from the pump reaching a predetermined pressure value at which the valve is set to close. If the valve is closed, the switch is activated and the motor and pump switched off and thereby the creation of the excessive pressure level of water to be emitted from the apparatus is prevented.

[0073] Referring now to FIG. 6 there is illustrated apparatus 102 in accordance with an embodiment of the invention in which the same is provided as a portable pressure washer apparatus, with a portable power supply in the form of battery pack although it should be appreciated that the invention as herein described, can be utilised in conjunction with apparatus which is provided for connection to a mains electricity supply and a mains water supply.

[0074] The apparatus housing 104 has an input 106 and leads to a wand portion 107 which has an output 108. The input 106 is provided to be connected to a source of liquid which in accordance with all of the embodiments most typically will be water but could other liquids which are desired to be applied under pressure. When the liquid is water the same can be water from a mains source, a container directly connected to the housing or via a pipe to allow water to be drawn from the container and into the input 106.

[0075] At the output 108, there may be provided means 109 to allow the user to adjust the particular form which the liquid is output such as, for example, a selection can be made between providing the output of the water in a spray pattern, a single stream or different types intermediate of the same.

[0076] Also providing in the housing are mechanical engagement means 110 which are provided to allow the mechanical engagement with the housing of a battery pack 112 as shown. The battery pack can be of any appropriate form and typically, is provided with, in a conventional manner, a series of terminals which when the battery pack is mechanically engagement with the housing, allow electrical contact to be made with terminals provided on the housing.

[0077] When the power cells and the battery pack are charged and the battery pack is mechanically connected to the housing, so power supply is provided for operation of the apparatus from the battery pack. Also provided in this housing, are user actuation means 116 to allow the user to switch the apparatus on and off by a pivotal movement of, in this embodiment, user actuation means in the form of a lever or handle about the pivot axis 115. When the handle is moved to the on position, this operates an electrical switch in the housing to connect power from the battery pack to operate a motor 120 and pump 122 and hence the generation of the output of water at a higher pressure from the output 108 than that at which it enters the apparatus at the input 106.

[0078] The handle portion is typically mounted adjacent to a gripping portion 118 via which the user can direct the housing and hence the flow of pressurised water therefrom onto a particular article to clean the same.

[0079] Also provided in the housing, is a control means 114 which is typically moveable along an axis between first and second positions. When in the unlocked position, the user actuation means 116 can be operated to allow the same to be pivotally moved between the on and off positions. When the control means is in a locking position, then the same engages with the user actuation means to retain the same in an on or off position.

[0080] Referring now to FIG. 7, there is illustrated in a schematic manner, the flow path of the liquid from the input 106 to the output 108 and as the liquid leaves the input 106 and moves as indicated by arrow 125, it moves towards a check assembly 128. When a check valve 140 provided in the check assembly is open, the water enters the pump 122, is pressurised and then passes towards the output 108. If the check valve 140 is closed, then the water that enters the input 106, is prevented from moving any further along the flow path than the check assembly 128 and this therefore prevents the passage of water through the apparatus in an unpressurised manner which would otherwise occur if the check assembly was not present and such a circumstance could arise if, for example, the mains water supply was turned on but the pump and motor were switched off. It will therefore be appreciated that in order for the apparatus to be operated to supply the pressurised water, the check valve 140 of the assembly 128 needs to be opened at the appropriate time. One assembly for doing so is illustrated in FIGS. 8a and b.

[0081] In accordance with the invention, the control means 114 provided in the apparatus, are located with an external portion 130 to allow user movement of the same between the first position shown in FIG. 8a and the second position shown in FIG. 8b. In one embodiment when the external portion 130 is in the position shown in FIG. 8a the same acts on rotatable member 132 which, at the opposing end, is in contact with the handle 116. It also is connected to member 134 which in FIG. 8a, has its free end being acted upon by spring 136 so that it is exerting no movement pressure on the movable portion 138 of the check valve 140 which is mounted downstream of the input 106. In the position shown in FIG. 8a no liquid is therefore able to pass through the check valve 140 and reach the pump 122 which is switched off so that the flow of the input unpressurised liquid through the apparatus is prevented.

[0082] When the user wishes to move the apparatus to an on condition they exert a movement force on the external portion 130 to move the same as indicated by arrow 142 to move the same against the biasing force of the spring 144 to the position shown in FIG. 8b. In turn, this frees the opposing end 146 of the rotatable member 132 and allows the user actuation means handle 116 to be moved by the user as indicated by arrow 148 to the position shown in FIG. 8b and, at the same time, operate the switch 150 and therefore turn the apparatus on. At the same time the member 134 is moved in the direction of arrow 152 by the movement of the rotatable member 132 to act against the spring and move the movable portion 138 of the check valve 140 inwardly of the check valve to move the same to an open position and hence allow the movement of the liquid through the input 106, check valve 140, check assembly 128 and onwardly to the pump 122 which is switched on.

[0083] When the handle 116 is moved back to the off position shown in FIG. 8a the spring 144 acts to move the external portion 130 back to the position of FIG. 8a and in turn the rotatable member 132 moves the member 134 back to the position shown in FIG. 8a to close the check valve 140.

[0084] Thus, there is provided in accordance with this embodiment of the invention, a check valve assembly to allow the operation of the check valve to an open position as and when required to allow the flow of liquid through the apparatus to be pressurised. Typically, when the control means are released, and at the same time, are released from contact with the valve seat, so a biasing means in the check valve will cause the movable portion 38 to return to a closed position and retain the same in that closed position until the control means are again used.

[0085] It is known that the viscosity of water can change as a direct result of the temperature in the environment in which the water is located. Furthermore, this temperature change can be as a result of the operation of apparatus in the vicinity of the water so that the heat generated by the operation of the apparatus is transferred to the water.

[0086] In turn, the change in heat and hence viscosity of the water, can also affect the performance of apparatus, which is used to, for example, pump the water as in accordance with the pump of the current apparatus.

[0087] In accordance with the invention, there is therefore provided a means of identifying and monitoring at least one parameter which is representative of, or can be used to calculate, the viscosity of water which is present or passing through the apparatus. In one embodiment, as result of the determination of the viscosity of the water in the pump at that time, and the effect of the viscosity of the water on the operation of the pump, control means can be provided to allow the particular operation of the pump at an instant of time to be adjusted to take into account the viscosity of the water and thereby provide a means of reacting to the feedback data which is received during operation of the apparatus.

[0088] In a further embodiment of the invention, the same or additional or alternative data which is fed back from the operation of the apparatus, can be used to alter the operation of the pump and/or other components of the apparatus such as, for example, a means of determining the level of charge in the battery pack which is used to operate the apparatus can be used so as to alter the operation of the apparatus as it is known that the pressure of water which can be achieved from the pump in the apparatus, will, unless modification to the operation of the apparatus is performed, reduce as a result of charge being lost in the battery pack during operation of the apparatus.

[0089] In one embodiment, the data includes the monitoring of the current in the battery pack and an adjustment can be made to the speed of operation of the pump.

[0090] In one embodiment, the motor which is used in the apparatus to operate the pump, is a brushless motor and furthermore, can be provided as an out runner brushless motor in that the central core is stationary and is surrounding outrider spins around the core or spindle.

[0091] It is found that this arrangement of a brushless motor, is advantageous in allowing the waterproofing or sealing of the apparatus so as to prevent or minimise the ingress of water into components of the apparatus such as electrical or electronic components for the control means so that the electrical or electronic components can be provided in a sealed compartment and the brushless motor itself, can be provided in another part of the housing or even in a separate housing to thereby be, exposed to water without adversely affecting the operation of the apparatus. In one embodiment, the exposure to water is deliberate in order to allow the water to provide a cooling effect on the motor as it performs and thereby prevent the same from overheating.

[0092] In one embodiment, preformed passageways for the flow of water in a controlled manner with respect to the motor, can be provided to thereby allow the desired cooling effect to be achieved and, furthermore, the placement of the apparatus into a body of water perhaps deliberately to fill a container from which water is to be pressurised, or in error due to accidental dropping of the apparatus, will not have an adverse effect on the operation of the apparatus.

[0093] In one embodiment, the battery pack, when located on receiving means on the apparatus body, is received into a compartment which, when the battery pack is in a mechanically and electrically located position, can be sealed so as to provide and retain the battery pack and in particular the interface between the battery pack and the remainder of the apparatus, to be retained in a sealed waterproof condition.

[0094] In one embodiment, the compartment is provided with a hinged or otherwise engageable lid which can be removed to allow the battery pack to be placed into and removed from the interface and a closed position to provide the seal around the lid and the body of the compartment to prevent the ingress of water into the compartment during use of the apparatus.

[0095] In one embodiment, it should be appreciated that although the apparatus diagrams as herein described, illustrate the use of a pump with three pump assemblies radially spaced around the central axis, the apparatus can be provided in other forms such as, for example, five pump assemblies are provided radially equally spaced around the central axis or more or even fewer pump assemblies may be provided and the adaptation of the same can be to provide a required operating characteristic of the particular version of the apparatus.

[0096] There is therefore created in accordance with the invention, apparatus which allows the water, which is input into the same, to be output from the same at a significantly greater pressure than that at which it enters. Furthermore, it is found by the use of pump as herein described, the difference in the pressure from the input to the output, is significantly greater than that which can be achieved by other portable apparatus and, as such, makes the practical usage of the apparatus in accordance with the invention such as to create a commercially viable product.