EP3752395A1

EP3752395A1 - Cleaning system and method for cleaning the inside of a container

Info

Publication number: EP3752395A1
Application number: EP19714833.1A
Authority: EP
Inventors: Jacobus Adriaan ZWEMER; Matthias VAN MIDDENDORP; Freddy LUIJENDIJK; Edwin DE BRUIN
Original assignee: Ticcc Holding BV
Current assignee: Ticcc Holding BV
Priority date: 2018-02-15
Filing date: 2019-01-18
Publication date: 2020-12-23
Also published as: WO2019160403A1

Abstract

The invention relates to a cleaning system and a method for cleaning the inside of a container, wherein the system comprises a base and an extendable member that is extendable from said base in an entry direction, wherein the system is provided with one or more drives for moving said base in a lateral direction, wherein the extendable member is arranged for holding a cleaning tool, wherein the extendable member or the cleaning tool is provided with one or more side detection sensors for detecting the side walls of the container, wherein the system further comprises a control unit that is operationally connected to the one or more drives and that is operationally connectable to the one or more side detection sensors, wherein the control unit is arranged for controlling the lateral position of the base in the lateral direction based on the detection signals from the one or more side detection sensors.

Description

Cleaning system and method for cleaning the inside of a container

BACKGROUND

The invention relates to a cleaning system and a method for cleaning the inside of a container.

US 4,112,533 A discloses an interior-exterior truck body wash, including an elongated extendable boom structure having a base and free ends. A carriage is provided from which the boom is supported in horizontal position with the base end of the boom supported from the carriage and the free end of the boom extendable relative to the carriage. The known interior-exterior truck body wash is further provided with a plurality of guide rails on the floor, to guide the trailer into a washing position. The carriage is shiftable back and forth along a horizontal path extending transversely of the boom and may be moved into registry behind a trailer from a position disposed along one side of the trailer. The free end of the boom, which carries a washing head assembly, is extended relative to the base end of the boom and the carriage into the rear of the trailer and forwardly through the interior of the trailer. The washing head assembly is operative to thoroughly wash and rinse the interior of the trailer during its forward movement through the interior thereof and its rearward movement there through upon retraction of the boom.

EP 2 484 456 B1 discloses a device for the cleaning and maintenance of the inner walls of box bodies and containers, wherein the device is arranged on a telescope-like, extendable sliding arm, wherein the device is formed from a geometric metal cross with vertical and horizontal metal arms, wherein on the free ends of each of the vertical and horizontal metal arms a drive motor and at least one cleaning brush are arranged, wherein the cleaning brush is driven by means of the drive motor. The vertical and horizontal metal arms of the metal cross are steplessly displaceable back and forth by means of a respective hydraulic cylinder. This allows for optimally setting the pressure exerted by the cleaning brushes on the inner walls of the container.

SUMMARY OF THE INVENTION

A disadvantage of the known interior-exterior truck body wash according to US 4, 112,533 A is that the trailer may be misaligned with respect to the direction of the boom, meaning that the longitudinal direction of the trailer is at a slightly oblique angle with respect to the longitudinal direction of the boom. Consequently, although the carriage may be moved into registry behind the rear of the trailer, this does not ensure that the washing head assembly, once it reaches the front of the trailer is still duly aligned with respect to the trailer. Depending on the angle of misalignment, the washing head assembly may be too far away from a particular surface of the interior to thoroughly wash and rinse said particular surface and/or the washing head may collide with or get stuck against another surface of the interior.

A disadvantage of the known device according to EP 2 484 456 B1 is that its hydraulically driven, individually adjustable arms make the device unnecessarily complex and subject to maintenance and/or repairs.

It is an object of the present invention to provide a cleaning system and a method for cleaning the inside of a container, wherein one or more of the aforementioned drawbacks of the prior art can be reduced or eliminated.

According to a first aspect, the invention provides a cleaning system for cleaning the inside of a container, wherein the container has a trailing end, a leading end and a box like body formed by at least a first side wall and a second side wall extending in a longitudinal direction between said trailing end and said leading end, wherein the cleaning system comprises a base that is arranged to remain outside of the container and an extendable member that is extendable from said base in an entry direction through the trailing end into the container towards the leading end thereof, wherein the cleaning system is provided with one or more drives for moving said base in a lateral direction perpendicular or substantially perpendicular to said entry direction, wherein the extendable member has a base end that is connected to the base and a distal end that is arranged for holding a cleaning tool, wherein the extendable member or the cleaning tool is provided with one or more side detection sensors for detecting the side walls of the container, wherein the cleaning system further comprises a control unit that is operationally connected to the one or more drives and that is operationally connectable to the one or more side detection sensors for receiving detection signals, wherein the control unit is arranged for controlling the lateral position of the base in the lateral direction based on the detection signals from the one or more side detection sensors.

The cleaning system according to the invention can thus effectively clean a container, even when the longitudinal direction of said container is misaligned with the entry direction of the extendable member. Moreover, because the base is movable in the lateral direction, the cleaning tool itself does not have complex drives or actuators to facilitate adjustability in said lateral direction. By using the control unit, the positioning of the base can be largely automated, so that the cleaning system can operate substantially autonomously.

In a preferred embodiment the control unit is arranged for controlling the lateral position of the base in the lateral direction such that the cleaning tool is centered between the two side walls. Hence, the cleaning tool can be centered between the two side walls, despite the misalignment of the container.

In a further embodiment the control unit is arranged for determining the center between the side walls at the location of the cleaning tool and for moving the base in the lateral direction towards said determined center position. This embodiment works best when the cleaning tool can easily follow the position of the base in the lateral direction. Hence, a change in the position of the base is immediately reflected in the position of the cleaning tool in the lateral direction. The cleaning tool may for example be provided with swivel wheels to facilitate movement in the lateral direction or the extendable member may be relatively rigid to forcefully impose the position of the base onto the cleaning tool.

In an alternative embodiment the control unit is arranged for determining the center between the side walls at the location of the cleaning tool and for moving the base in the lateral direction away from said determined center position during the extension of the extendable member in the entry direction. This embodiment works best when the cleaning tool is not able to move easily together with the base in the lateral direction. Instead, the position of the base in the lateral direction can be used to counter-steer the cleaning tool such that it pivots towards the determined center and/or into alignment with the center line of the container.

In a preferred embodiment thereof the control unit is arranged for moving the base in the lateral direction towards said determined center position during a retraction of the extendable member in a retraction direction opposite to the entry direction. During the retraction, counter-steering the base would not work, because during the retraction the base is located in front of the cleaning tool, considered in the retraction direction. Hence, moving the base towards the determined center can actually cause the cleaning tool to pivot towards the determined center and/or into alignment with the center line of the container.

In a further embodiment the control unit is arranged for continuously controlling the lateral position of the base in the lateral direction based on the detection signals from the one or more side detection sensors. By continuously controlling the lateral position of the base, the cleaning tool can be kept in an optimal position for cleaning throughout its operation.

In an alternative embodiment the control unit is arranged for controlling the lateral position of the base in the lateral direction when the cleaning tool is misaligned with respect to the center of container between the side walls and said misalignment exceeds a predetermined threshold value. By intermittently controlling the lateral position of the base, the one or more drives of the base can be operated less frequently, thus allowing them to cool down between movements. Also, less computing power is required at the control unit. Preferably, the threshold value is set in a range of two to twenty centimeters. Within said threshold value, the cleaning tool is still at an acceptable distance from both side walls.

In a further embodiment the cleaning system comprises one or more guiding members for guiding the movement of said base in the lateral direction. The base can be moved over the one or more guiding members more reliably and/or more accurately.

Preferably, the one or more guiding members are two rails extending mutually parallel in the lateral direction. The rails can ensure a linear movement of the base in the lateral direction. In a further embodiment thereof the base is provided with wheels for rolling over said rails, wherein the one or more drives are arranged for driving one or more of said wheels. By driving at least one of the wheels, the base can be moved in the lateral direction. Preferably, at least two wheels are driven to prevent shearing of the base relative to the rails.

In another embodiment the cleaning system comprises the cleaning tool, wherein the one or more side detection sensors are provided on the cleaning tool and wherein the control unit is operationally connected or connectable to the one or more side detection sensors at said cleaning tool. With the cleaning tool included as part of the cleaning system, the control unit can be securely connected to the one or more side detection sensors.

Preferably, the cleaning tool is a washing head, wherein the washing head comprises a coupling member for coupling the washing head to the distal end of the extendable member and a first brush assembly and a second brush assembly for cleaning the first side wall and the second side wall, respectively, in the lateral direction and a third brush assembly and a fourth brush assembly for cleaning the bottom wall and the top wall, respectively, in a height direction perpendicular to the entry direction and the lateral direction, wherein each brush assembly comprises a brush and a brush holder for holding the respective brush with respect to the coupling member, wherein either the first brush assembly and the second brush assembly are located in front of the third brush assembly and the fourth brush assembly and are movable with respect to the coupling member in the lateral direction or the third brush assembly and the fourth brush assembly are located in front of the first brush assembly and the second brush assembly in the entry direction and are movable with respect to the coupling member in the height direction.

By moving either the first brush assembly and the second brush assembly or the third brush assembly and the fourth brush assembly in front of the third brush assembly and the fourth brush assembly or the first brush assembly and the second brush assembly, respectively, the leading end of the container can be cleaned more effectively. In particular, the first brush assembly and the second brush assembly can be moved in the lateral direction without being obstructed by the third brush assembly or the fourth brush assembly or the third brush assembly and the fourth brush assembly can be moved in the height direction without being obstructed by the first brush assembly and the second brush assembly.

In a preferred embodiment thereof the third brush assembly and the fourth brush assembly are located in front of the first brush assembly and the second brush assembly in the entry direction and are movable with respect to the coupling member in the height direction. By moving the third brush assembly and the fourth brush assembly in front of the first brush assembly and the second brush assembly, the leading end of the container can be cleaned more effectively, as the third brush assembly and the fourth brush assembly can move in the height direction without being obstructed by the first brush assembly and the second brush assembly.

In a further embodiment the first brush assembly and the second brush assembly are fixed with respect to the coupling member in the lateral direction and/or the height direction. As discussed before, as the base is movable in the lateral direction, the cleaning tool itself does not require complex drives or actuators to facilitate adjustability in said lateral direction. In particular, the first brush assembly and the second brush assembly can simply be fixed to the coupling member. Provided that the bristles of the brushes of the first brush assembly and the second brush assembly can be compressed sufficiently to adapt to the smallest of a range of typical containers and the same bristles can still effectively clean the side walls of the widest of the range of typical containers, then the first brush assembly and the second brush assembly do not need to be movable. By fixing the first brush assembly and the second brush assembly with respect to the coupling member, the washing head can be simplified.

In a further embodiment the brushes of the first brush assembly and the second brush assembly define a first outer width of the washing head in the lateral direction and wherein the brushes of the third brush assembly and the fourth brush assembly define a second outer width of the washing head in the lateral direction equal to or greater than the first outer width. Hence, the brush of the third brush assembly can effectively clean the bottom wall and simultaneously contribute to cleaning both side walls. Similarly, the brush of the fourth brush assembly can effectively clean the top wall and simultaneously contribute to cleaning both side walls.

In a further embodiment the third brush assembly is movable in the height direction into a position in which the brush of the third brush assembly partially extends in the height direction to a level below the lowest point of the brush of the first brush assembly and/or the second brush assembly. When the brush of the third brush assembly extends only partially below the brushes of the first brush assembly and/or the second brush assembly, it can contribute to cleaning the sidewalls, at least at or near the bottom wall. In other words, the brushes of the first, second and third brush assemblies still overlap each other in the height direction. Hence, the effective height of the washing head for cleaning the side walls can be increased without creating gaps between the brushes in the height direction .

Additionally or alternatively, the fourth brush assembly is movable in the height direction into a position in which the brush of the fourth brush assembly partially extends in the height direction to a level above the highest point of the brush of the first brush assembly and/or the second brush assembly. When the brush of the fourth brush assembly extends only partially above the brushes of the first brush assembly and/or the second brush assembly, it can contribute to cleaning the sidewalls, at least at or near the top wall. In other words, the brushes of the first, second and fourth brush assemblies still overlap each other in the height direction. Hence, the effective height of the washing head for cleaning the side walls can be increased without creating gaps between the brushes in the height direction.

In yet another embodiment the container has an inclined bottom wall, wherein the base comprises a frame, wherein the base end of the extendable member is hingably coupled to the frame so as to be pivotable about a pivot axis parallel or substantially parallel to the lateral direction, wherein the cleaning tool is provided with one or more wheels for running over the bottom wall and following the inclination of the bottom wall as the extendable member pivots about the pivot axis. The cleaning tool can thus automatically or autonomously follow the inclination of the bottom wall by running with its one or more wheels over said bottom wall. The pivotable extendable member can provide the required freedom of movement.

In an embodiment thereof the one or more wheels are steerable, wherein the control unit is operationally connected to the one or more wheels to steer said one or more wheels. Hence, any remaining misalignment of the cleaning tool that is not compensated by the movement of the base can be corrected at the cleaning tool itself by slightly steering the cleaning tool in the right direction.

In a further embodiment thereof the base is further provided with a lifting member for pivoting the extendable member with respect to the frame about the pivot axis. By pivoting the extendable member, the height of the cleaning tool supported thereon can be adjusted to match the level of the bottom wall or to reduce the load at the cleaning tool.

In a further embodiment thereof the cleaning tool is provided with one or more load sensors for measuring the load on the cleaning tool. The measured load can be used as an indication whether the cleaning tool is correctly supported on the bottom wall of the container.

In a further embodiment thereof the one or more load sensors are arranged for actuating the lifting member when a threshold value for the load has been exceeded. The load increases when the extendable member is extended in the entry direction. The lifting member can compensate for increased loads .

Preferably, at least one of the one or more load sensors is a load cell that is located at the wheels of the cleaning tool. Hence, the load can be measured directly at the one or more wheels of the cleaning tool.

According to a second aspect, the invention provides a method for cleaning the inside of a container with the use of the cleaning system according to any one of the aforementioned embodiments, wherein the method comprises the steps of operationally connecting the control unit to the one or more side detection sensors for receiving the detection signals and controlling the lateral position of the base in the lateral direction with the control unit based on the detection signals from the one or more side detection sensors.

The method relates to the implementation of the aforementioned cleaning system and thus has the same technical advantages which will not be repeated hereafter.

In a preferred embodiment of the method, the control unit controls the lateral position of the base in the lateral direction such that the cleaning tool is centered between the two side walls.

In a further embodiment of the method, the control unit determines the center between the side walls at the location of the cleaning tool and moves the base in the lateral direction towards said determined center position .

In an alternative embodiment of the method, the control unit determines the center between the side walls at the location of the cleaning tool and moves the base in the lateral direction away from said determined center position during the extension of the extendable member in the entry direction. Preferably, the control unit moves the base in the lateral direction towards said determined center position during a retraction of the extendable member in a retraction direction opposite to the entry direction .

In a further embodiment of the method, the control unit continuously controls the lateral position of the base in the lateral direction based on the detection signals from the one or more side detection sensors.

In an alternative embodiment of the method, the control unit controls the lateral position of the base in the lateral direction when the cleaning tool is misaligned with respect to the center of container between the side walls and said misalignment exceeds a predetermined threshold value. Preferably, the threshold value is set in a range of two to twenty centimeters.

In a further embodiment of the method, in a situation in which the container is positioned with its longitudinal direction offset over an oblique angle with respect to the entry direction of the extendable member, the control unit controls the lateral position of the base based on the detection signals from the one or more side detection sensors to compensate for this offset.

In a further embodiment of the method, the container is provided with doors for opening and closing the trailing end of the container, wherein the method comprises the step of fixing the doors relative to the surroundings in a position in which the doors extend parallel or substantially parallel to the respective side walls. By fixing the doors in said position, the doors can be cleaned as the cleaning tool moves into and/or out of the container.

In a further embodiment of the method, the container has an inclined bottom wall, wherein the base comprises a frame, wherein the base end of the extendable member is hingably coupled to the frame so as to be pivotable about a pivot axis parallel or substantially parallel to the lateral direction, wherein the cleaning tool is provided with one or more wheels for running over the bottom wall and following the inclination of the bottom wall as the extendable member pivots about the pivot axis.

In a further embodiment thereof, the method further comprises the step of using a lifting member to pivot the extendable member about the pivot axis and thereby raising or lowering the cleaning tool relative to the base and/or the container.

In a further embodiment thereof the base is provided with one or more load sensors for measuring the load on the cleaning tool.

Preferably, the one or more load sensors are arranged for actuating the lifting member when a threshold value for the load has been exceeded.

The various aspects and features described and shown in the specification can be applied, individually, wherever possible. These individual aspects, in particular the aspects and features described in the attached dependent claims, can be made subject of divisional patent applications .

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be elucidated on the basis of an exemplary embodiment shown in the attached schematic drawings, in which:

figures 1A-1F show side views of a cleaning system during the steps of a method for cleaning the inside of a container according to the invention;

figures 2A-2C show top views of the cleaning system according to figures 1A-1F during steps of the method for cleaning the container; figures 3A-3H show top views of the cleaning system according to figures 1A-1F during steps of an alternative method for cleaning the container;

figure 4 shows a side view of a detail of the cleaning system of figure 1A;

figure 5 shows an isometric view of a washing head of the cleaning system according to figure 1A;

figure 6 shows a cross section of the washing head according to line VI - VI in figure 5; and

figure 7 shows a cross section of the washing head according to line VII - VII in figure 6.

DETAILED DESCRIPTION OF THE INVENTION

Figures 1A-1F, 2A-2C and 3A-3H show a cleaning system 1 according to an exemplary embodiment of the invention. The cleaning system 1 may be used to clean containers, in particular shipping containers or reefers, or any other box-like transport means.

Figure 1A shows a cleaning area 8 and a truck and trailer combination 9 that is positioned in said cleaning area 8 relative to the cleaning system 1. The truck and trailer combination 9 carries a container 90. The container 90 has a trailing end 91, a leading end 92 and a box like body formed by a plurality of walls extending between said trailing end 91 and said leading end 92 in a longitudinal direction L. As shown in top view in figure 2A, the container 90 has a center line C between the side walls 95, 96 parallel to said longitudinal direction L. The plurality of walls comprises a bottom wall 93 and a top wall 94, as shown in figure 1A, and a first side wall 95 and a second side wall 96, as shown in figure 2A. The container 90 may further include two doors 97, as shown in figure 2A, to open and close the trailing end 91 of the container 90. In figures 1A-1F, the second wall 96 has been hidden to expose the cleaning system 1 inside the container 90. Similarly, in figures 2A-2C and 3A-3H, the top wall 94 has been hidden, to expose the cleaning system 1 inside the container 90.

In this example, the cleaning area 8 comprises a pit 81 for receiving the truck and trailer combination 9 and a platform 82 for supporting the cleaning system 1 relative to the truck and trailer combination 9 in the pit 81. Alternatively, the cleaning area 8 may be relatively flat to allow truck and trailer combinations to drive into and out of the cleaning area 8 in the same direction. As shown in figure 2A, the pit 81 may comprise one or more lanes 83, 84 to receive one or more truck and trailer combinations 9. The truck and trailer combination 9 is maneuvered into a position in one of the lanes 83, 84 in which the trailing end 91 of the container 90 faces the platform 82. Alternatively, the container 90 may be supplied to the pit 81 by different means, e.g. by a reachstacker or another container lifting means, in which case the truck and trailer combination 9 is absent. Preferably, the pit 81 is arranged at a downwardly sloping angle towards the platform 82. As a result, the container 90, an in particular its bottom wall 93, is placed at the same or substantially the same downwardly sloping angle from the leading end 92 towards the trailing end 91 such that water, dirt and cleaning agents can easily be flushed out of the container 90 under the influence of gravity. Alternatively, the container 90 may be placed on supports that position it at the same downwardly sloping angle. In such a case, there may be no pit or the pit may be level.

As shown in figure 1A, the cleaning system 1 comprises a base 2 that is arranged to remain outside of or external to the container 90 and an extendable member 3 that is extendable from said base 2 in an entry direction E through the trailing end 91 into the container 90 and towards the leading end 92 thereof. In this example, the base 2 comprises a frame 20 for holding various components of the cleaning system 1. The extendable member 3 is supported by and/or connected to the frame 20 of the base 2 in a manner that will be described in more detail hereafter .

As shown in figures 1A and 2A, the cleaning system 1 further comprises a cleaning tool 4 that is held by the extendable member 3 with respect to the base 2. In this exemplary embodiment, the cleaning tool 4 is a washing head 40 for washing the container 90. Alternatively, the cleaning system 1 may be fitted with a different cleaning tool, e.g. a rinsing head or a drying head (not shown) . In yet another alternative embodiment, two or more cleaning systems may be provided (not shown) which may alternate positions to quickly switch between rinsing, washing, drying and/or other steps of a method for cleaning the inside of a container. Said two or more cleaning systems could for example perform parallel cleaning processes in respective lanes 83, 84 in figure 2A.

Preferably, the cleaning area 8 or the cleaning system 1 comprises one or more presence detection sensors (not shown) to detect the presence of one or more truck and trailer combinations 9 in the respective lanes 83, 84 in figure 2A.

As further shown in figure 2A, the base 2 is horizontally movable in a lateral direction T transverse, perpendicular or substantially perpendicular to the entry direction E of the extendable member 3 into different lateral positions relative to the container 90. In this example, the cleaning system 1 comprises one or more guiding members 10 for guiding the movement of said base 2 in the lateral direction T. More in particular, the one or more guiding members 10 are two rails 11, 12 extending mutually parallel in the lateral direction T. As best seen in figure 1A, the base 2 is provided with wheels 21 for rolling over said rails 11, 12. Alternatively, the base 2 may be provided with wheels 21 that directly contact and run on the platform 82 of the cleaning area 8. The cleaning system 1 is further provided with one or more drives 22 for driving the wheels 21, and thus the base 2, in the lateral direction T over the rails 11, 12. The base 2 further holds one or more reservoirs 23 for water and/or cleaning agents.

As best seen in figures 1A-1F, the extendable member 3 is steplessly and/or continuously extendable in the entry direction E and retractable in a retraction direction R opposite to the entry direction E. The extendable member 3 has a base end 31 that is connected to the base 2 and a free end or distal end 32 that holds the cleaning tool 4. The base end 31 is preferably hingably coupled to the frame 20 of the base 2 so as to be pivotable about a pivot axis P parallel or substantially parallel to the lateral direction T. The base 2 is further provided with a lifting member 24 for pivoting the extendable member 3 with respect to the frame 20 about the pivot axis P. The lifting member 24 is preferably a hydraulic cylinder. By pivoting the extendable member 3 about the pivot axis P, the cleaning tool 4 at the distal end 32 of the extendable member 3 can be raised or lowered with respect to the base 2 and/or the container 90, e.g. to position the cleaning tool 4 at the same level as the bottom wall 93 or to follow the sloping angle of said bottom wall 93 in the entry direction E as a result of the slope of the pit 81.

In this exemplary embodiment, the extendable member 3 is a telescopic boom having a plurality of boom sections 33 that telescopically slide or roll into and out of one another. Each boom section 33 except for the boom section 33 closest to the distal end 32 are provided with a sliding roller 34 for supporting the next boom section 33 during extension of the extendable member 3 in the entry direction E. The combined length of the boom sections 33, when extended, is preferably sufficient to extend the extendable member 3 over an extension stroke up to the leading end 92 of the container 9. The extendable member 3 may alternatively comprise a different extendable mechanism, for example a scissor mechanism.

In figure 1A, the extendable member 3 is retracted such that the cleaning tool 4 is in a retracted position at the trailing end 91 of the container 90. The cleaning tool 4 is ready to be extended into the container 9 in said entry direction E. Figures 1A-1C show the extension of the extendable member 3 in the entry direction E towards the leading end 92 of the container 90, until the cleaning tool 4 is in an extended position at said leading end 92 in figure 1C. In figures 1D-1F, the leading end 92 is cleaned by the cleaning tool . Figure IF shows that the cleaning tool 4 is ready to be retracted in the retraction direction R.

As previously discussed, the cleaning tool 4 as shown in figures 1A-1F, 2A-2C and 3A-3H is a washing head 40. Figure 5 shows the washing head 40 in more detail. The washing head 40 comprises a coupling member 6 for coupling the washing head 40 to the distal end 32 of the extendable member 3. The washing head 40 is therefore connected to the base 2 via the extendable member 3. The washing head 40 is further provided with one or more wheels 62, as best seen in figures 1A-1F, for running or rolling over the bottom wall 93 of the container 9. The washing head 40 further comprises a first brush assembly 41 for cleaning the first side wall 95, a second brush assembly 42 for cleaning the second side wall 96, a third brush assembly 43 for cleaning the bottom wall 93 and at least a part of the leading end 92 and a fourth brush assembly 44 for cleaning the top wall 94 and at least a part of the leading end 92. Preferably, the third brush assembly 43 and the fourth brush assembly 44 are additionally arranged for cleaning both side walls 95, 96 at or near the bottom wall 93 and at or near the top wall 94, respectively, in a manner that will be described hereafter in more detail.

As shown in detail in figure 4, the cleaning tool 4 may optionally be provided with one or more load sensors 63 for measuring the load on the cleaning tool 4. In this example, the one or more load sensors 63 comprises a load cell that is located at the one or more wheels 62 of the cleaning tool 4, in particular between the one or more wheels 62 and the coupling member 6. Alternatively, the load may be derived from the pressure in the lifting member 24. The lifting member 24 may be actuated automatically or autonomously when a threshold value for the load has been exceeded. The load on the cleaning tool 4 increases when the extendable member 3 is extended into the container 90 in the entry direction E. As a result of the actuating of the lifting member 24, the extendable member 3 is pivoted about the pivot axis P to effectively reduce the load on the cleaning tool 4.

As shown in figure 5, each brush assembly 41-44 comprises a brush 5 and a brush holder 46 for holding the respective brush 5 with respect to the coupling member 6. The brush holder 46 may be provided with a splash fender to shield the coupling member 6 from water and/or cleaning agents. Said splash fenders may also be used to fit additional spout or nozzles (not shown) for spraying water and/or cleaning agents onto the brushes 5 and/or the walls 91-96 of the container 9. The brushes 5 of the first brush assembly 41 and the second brush assembly 42 are rotatable with respect to their respective brush holders 46 about a first brush axis B1 and a second brush axis B2 parallel to said first brush axis Bl, respectively. Said first brush axis Bl and said second brush axis B2 preferably extend in an upright or vertical direction. The brushes 5 of the third brush assembly 43 and the fourth brush assembly 44 are rotatable with respect to their respective brush holders 46 about a third brush axis B3 and a fourth brush axis B4 parallel to the third brush axis B3, respectively, . Said third brush axis B3 and a fourth brush axis B4 extend perpendicular to the first brush axis Bl and the second brush axis B2, preferably in a level or horizontal direction. Each brush assembly 41-44 further comprises a drive 47 for driving the rotation of the brushes 5 about their respective brush axes B1-B4.

Figure 7 shows the drive 47 in cross section at a center plane M of the brush 5, perpendicular to the brush axis B4. The drive 47 comprises a motor 48 and a transmission member 49, e.g. a chain or belt, that is driven by said motor 48 and engages the brush 5 at the center plane M thereof, in a manner that will be described in more detail hereafter. By driving the brush 5 at the center plane M, the ends of said brush 5 can be kept free of any objects that could interfere with the ability of the brush 5 to clean the container 9.

As best seen in figure 6, the brush holders 46 of the first brush assembly 41 and the second brush assembly 42 are directly mounted and/or fixed to the coupling member 6 and thus are arranged to remain stationary with respect to the coupling member 6 during cleaning. In other words, their respective brushes 5 are rotatable about the respective brush axes Bl, B2, while the brush axes Bl, B2 themselves do not move and/or translate with respect to the coupling member 6 in the lateral direction T. The first brush assembly 41 and the second brush assembly 42 may be fixed to the coupling member 6 at the position of their respective drives 47 or at any other position along the coupling member 6.

In contrast, the brush holders 46 of the third brush assembly 43 and the fourth brush assembly 44, as shown in figure 5, are connected to the coupling member 6 in a way so as to be movable in a height direction H perpendicular to their respective brush axes B3, B4, the entry direction E and/or the lateral direction T. In particular, the coupling member 6 is provided with one or more linear guides 61 extending in the height direction H and the brush holders 46 of the third brush assembly 43 and the fourth brush assembly 44 are arranged to slide in said height direction H along the one or more linear guides 61. In this example, a linear drive (not shown) is provided between the coupling member 6 and the brush holders 46 of the third brush assembly 43 and the fourth brush assembly 44 for moving said brush holders 46 up and down along the one or more linear guides 61.

The third brush assembly 43 and the fourth brush assembly 44 are arranged in front of the first brush assembly 41 and the second brush assembly 42 in the entry direction E. Consequently, the brushes 5 of the third brush assembly 43 and the fourth brush assembly 44 are in a position to clean the leading end 92 of the container 90 when the washing head 40 is in the extended position of figures 1D-1F. By moving the third brush assembly 43 and the fourth brush assembly 44 up and down in the height direction H, the entire surface of the leading end 92 of the container 9 can be cleaned.

It will be apparent to one skilled in the art that in an alternative embodiment (not shown) , the third brush assembly 43 and the fourth brush assembly 44 may be fixed to the coupling member 6 and the first brush assembly 41 and the second brush assembly 42 are movable in the lateral direction T with respect to the third brush assembly 43 and the fourth brush assembly 44, respectively. In that case, the one or more linear guides 61 extend in the lateral direction T. The first brush assembly 41 and the second brush assembly 42 would be in front of the third brush assembly 43 and the fourth brush assembly 44 to clean the leading end 92 of the container 90.

Figure 6 shows the brush 5 of the fourth brush assembly 44 in cross section. Said brush 5 is exemplary for the brushes 5 of the other brush assemblies 41-43. Said brush 5 comprises a brush core 50 extending in and/or defining the direction of the respective brush axis B4. Preferably, the brush core 50 is the same for all of the brushes 5. The brush 5 further comprises one or more bristle sections 51-54 arranged side-by-side in a direction parallel to the respective brush axis B4. Each bristle section 51-54 comprises a plurality of bristles distributed in a circumferential direction about the brush core 50 and extending radially outwards from said brush core 50. In this exemplary embodiment, the brush core 50 has a core diameter D1 in the range of ten to twenty-five centimeters. The bristles of the bristle sections 51-54, when uncompressed, form a circumferential brush surface with a brush diameter D2 in the range of forty to one-hundred centimeters .

As best seen in figure 5, the brushes 5 of the first brush assembly 41 and the second brush assembly 42 comprise a main part 55. The brushes 5 of the third brush assembly 43 and the fourth brush assembly 44 are provided with the same main part 55 that is extended on both sides in the direction of their respective brush axes B3, B4 with an additional, separately mountable extension part 56. Hence, all brushes 5 can be assembled in substantially the same manner out of the same main part 55 and an optional extension part 56, thus significantly simplifying the construction thereof. As shown in figure 6, the main part 55 of the brush 5 has a first length XI in a direction parallel to the respective brush axis B4. The combination of the main part 55 and the extension parts 56 on either side of the main part 55 has a second length X2 in a direction parallel to the respective brush axis B4.

As further shown in figure 6, the brush 5 comprises a central bristle section 51 on either side of the center plane M, followed on either side by a main bristle section 52, an reinforcement bristle section 53 and a side bristle section 54. The central bristle sections 51, the main bristle sections 52 and the reinforcement bristle sections 53 form the main part 55 of the brush 5. The side bristle section 54 forms the extension part 56 on either side of the main part 55.

The bristles at the central bristle sections 51 are pointed slightly towards each other from opposite side of the center plane M to substantially close the circumferential brush surface around the connection of the drive 47 to the brush core 50 at said center plane M. In particular, it can be observed in figure 6 that the transmission member 49 extends from the motor 48 to the brush core 50 through a gap 57 in between the central bristle sections 51, which gap 57 is substantially closed at the outside of the brush 5 by the at least partially overlapping bristles of the respective central bristle sections 51.

The bristles at the main bristle sections 52 are arranged for cleaning surfaces of the container 90 in or substantially in the circumferential direction of the brush 5. In this particular example, the bristles in the main bristle sections 52 have a cross shaped or X-shaped profile (not shown) so that the bristles not only clean at their respective outer ends, but also at the sides along the length of the bristles.

The bristles at the reinforcement bristle sections 53 are more resilient than the bristles of the adjacently located main bristle sections 52 and are pointed slightly towards said adjacently located main bristle sections 52. At such orientation, the bristles of the reinforcement bristle sections 53 form a less flexible ring at one side of the adjacently main bristle sections 52 that can prevent that the bristles of said adjacently located main bristle sections 52 slack under the influence of gravity. This is particularly relevant for the vertically extending brushes 5 of the first brush assembly 41 and the second brush assembly 42 in figure 5. The bristles at the reinforcement bristle sections 53 are preferably mounted to a ring 58 that is separable and/or detachable from the brush core 50.

The bristles of the side bristle sections 54 are again more rigid, less flexible and/or less resilient than the bristles of the main bristle sections 52. However, in contrast to the bristles of the reinforcement bristle sections 53, the bristles of the side bristle sections 54 extend under an oblique angle with respect to the respective brush axis B4 and are pointed in a direction away from the center plane M to clean surfaces of the container 90 both in the circumferential direction and at the sides of the brush 5. Hence, the side bristle sections 54 are particularly useful for cleaning at least part of the sidewalls 95, 96 as shown in figure 2A and/or the corners between said sidewalls 95, 96, the bottom wall 93 and the top wall 94 in figure 1A. The bristles of the side bristle sections 54 are mounted to a detachable end section or end cap 59 of the brush core 50.

As can be observed in figure 5, the brushes 5 of the first brush assembly 41 and the second brush assembly 42 define a first outer width W1 of the washing head 40 in the lateral direction T, in particular the first outer width Wl of the washing head 40 in the lateral direction T from the brush 5 of the first brush assembly 41 to the brush 5 of the second brush assembly 42, including their respective uncompressed brush diameters D2. Said first outer width Wl is preferably equal to or larger than the width of the container 90 between the side walls 95, 96. More preferably, the first outer width Wl is chosen such that the bristles of the brushes 5 are compressed or bend to reduce the diameter of the brushes 5 with at least five centimeters to ensure proper pressure being applied during cleaning. Considering that a typical container, as shown in figure 2A, has a width of approximately two-and-a-half meters between the side walls 95, 96, the first outer width Wl should preferably be at least two meters and sixty centimeters. The resilience of the bristles means that the brushes 5 can accommodate different container widths in the range of two meters and twenty centimeters to two meters and sixty centimeters, without the need to change the first brush assembly 41 and the second brush assembly 42 and/or without the need to make the first brush assembly 41 and the second brush assembly 42 movable.

It can further be observed from figure 5 that the brushes 5 of the first brush assembly 41 and the second brush assembly 42 have a first length XI in the height direction H that is less than the height between the bottom wall 93 and the top wall 94 of the container 90 in figure 1A. Hence, the first brush assembly 41 and the second brush assembly 42 according to the exemplary embodiment as shown are not capable of cleaning the entire height of the side walls 94, 95.

The third brush assembly 43 and the fourth brush assembly 44 are however movable in the height direction H into a position in which their brushes 5 extend partially beyond the brushes 5 of the first brush assembly 41 and the second brush assembly 42 in said height direction H. Moreover, as previously discussed and shown in figure 6, the brushes 5 of the third brush assembly 43 and the fourth brush assembly 44 are provided with extension parts 56 that extend the length of said brushes 5 to the second length X2. Hence, as shown in figure 5, the brushes 5 of the third brush assembly 43 and the fourth brush assembly 44 define a second outer width W2 of the washing head 40 equal to the second length X2 in the lateral direction T. Said second outer width W2 is preferably equal to or greater than the first outer width W1 defined by the brushes 5 of the first brush assembly 41 and the second brush assembly 42. Consequently, the brushes 5 of the third brush assembly 43 and the fourth brush assembly 44 - if positioned correctly - are capable of cleaning the remaining surfaces of the side walls 94, 95 during the extension of the extendable member 3 in the entry direction E in figures 2A-2C. Hence, in combination, the third brush assembly 43 and the fourth brush assembly 44 supplement the first brush assembly 41 and the second brush assembly 42.

As shown in figure 2A, the cleaning system 1 further comprises a control unit 7 and a plurality of sensors that are operationally and/or electronically connected or connectable to the control unit 7. The plurality of sensors are arranged for detecting the position of the cleaning tool 4 relative to the base 2 and/or for detecting the position of the cleaning tool 4 relative to the container 90. In particular, the cleaning system 1 comprises one or more side detection sensors 71 for detecting the distance of the extendable member 3 or the cleaning tool 4 to one or both of the sidewalls 95, 96 of the container 90 in the lateral direction T. The cleaning system 1 may additionally comprise a bottom detection sensor 72 and/or a top detection sensor 73 for detecting the distance of the extendable member 3 or the cleaning tool 4 to the bottom wall 93 and the top wall 94, respectively, in a vertical direction V. In this example, said one or more side detection sensors 71, the bottom detection sensor 72 and/or the top detection sensor 73 are provided on the cleaning tool 4. Alternatively, said sensors 71, 72, 73 may be positioned on the extendable member 3 at or near the cleaning tool 4. Preferably, the plurality of sensors 71, 72, 73 are laser sensors. The laser beams are schematically shown with respective dashed lines in figures 1A-1F, 2A-2C and 3A-3H. Alternatively, other suitable detection means can be used, e.g. radar, inductive or ultrasonic means.

The cleaning system 1 may additionally comprise an extension sensor 74 for detecting the distance between the cleaning tool 4 and the base 2 in the entry direction E. Said extension sensor 74 may be arranged on either the base 2, the extendable member 3 or the cleaning tool 4. Alternatively, the cleaning system 1 may be provided with a distance sensor (not shown) to detect the distance from the cleaning tool 4, the extendable member 3 or the base 2 up to the leading end 92 of the container 90. Preferably, said distance sensor is located on the cleaning tool 4 facing towards the leading end 92. The distance sensor may also be replaced by a mechanical switch or a proximity switch that is actuated when the cleaning tool 4 reaches the leading end 92.

The control unit 7 is further operationally and/or electronically connected or connectable to the one or more drives 22 of the base 2 for controlling said one or more drives 22 in response to detection signals received from the plurality of sensors 71-74. In particular, said control unit 7 is arranged for controlling the lateral position of the base 2 with respect to the container 90 based on detection signals from the one side detection sensors 71.

The control unit 7 may also be operationally and/or electronically connected or connectable to the load sensor 63 as shown in figure 4 to actively control the angular position of the extendable member 3 about the pivot axis P in response to the measured load or to determine whether the cleaning tool 4 has been correctly placed and/or supported on the bottom wall 93 of the container 9.

A method for cleaning the inside of a container 90 using the previously discussed cleaning system 1 will be elucidated below with reference to figures 1A-1F, 2A-2C and 4-7.

Figure 1A shows the situation in which the base 2 of the cleaning system 1 is positioned opposite to the trailing end 91 of the container 90 and wherein the cleaning tool 4 is positioned at said trailing end 91 to start the cleaning operation. The third brush assembly 43 and the fourth brush assembly 44 may be moved towards each other to stay clear of the bottom wall 93 and the top wall 94, respectively, during the stroke in the entry direction E. Optionally, the third brush assembly 43 and the fourth brush assembly 44 into a center position at the center of the cleaning tool 4 to determine their respective starting positions. The doors 97 of the container 90 have been opened and are optionally fixed with respect to the surroundings, preferably in an orientation in which the cleaning tool 4 can also clean said doors 97. More preferably, the doors 97 are fixed in an orientation in which they extend parallel or substantially parallel to the respective side walls 95, 96.

Depending on the height of the bottom wall 93 at the trailing end 91 of the container 90 relative to the platform 81, the lifting member 24 may be operated to lift the extendable member 3, and consequently the cleaning tool 4 supported thereon to an appropriate height . The load sensor 63 at the one or more wheels 62 can be used to determine whether the cleaning tool 4 has been correctly placed and/or supported on the bottom wall 93.

Alternatively, a mechanical switch, e.g. a pivot element, or other suitable detection means can be used, e.g. radar, inductive or ultrasonic means, to detect contact with the bottom wall 93 as the cleaning tool 4 moves into the container 90. The same situation is shown in top view in figure 2A. As shown in figure 2A, the truck-trailer combination 9 is not perfectly positioned in the lane 83 and - as a result - the longitudinal direction L or the center line C of the container 90 is offset over a small oblique angle A, e.g. one or two degrees, with respect to the entry direction E of the extendable member 3. The control unit 7 may be configured, programmed or arranged for automatically or autonomously compensating for this offset by adjusting the lateral position of the base 2 in the lateral direction T based on detection signals from the one or more side detection sensors 71 such that the cleaning tool 4, at least at the start of the cleaning operation, is centered between the two side walls 95, 96 at the trailing end 91 of the container 90. During the approach of the cleaning tool 4 towards the trailing end 91 of the container 9, the cleaning tool 4 may already be activated to clean the doors 97 of the container 90.

Figures IB and 1C show steps of an extension stroke in which the extendable member 3 is extended to move the cleaning tool 4, in this example in the form of a washing head 40, into the container 90 in the entry direction E. During said extension stroke the nozzles (not shown) may be activated to spray cleaning agents onto the inside of the container 90. Optionally, the brushes may already be rotated to apply or at least partially clean the walls of the container 90. In this example however, the brushes are not actively cleaning the inside of the container 90 during the extension stroke. Figures IB and 1C show two steps of extending the extendable member 3 in the entry direction E over the extension stroke towards the leading end 92 of the container 90 while the cleaning tool 4 moves along the inside of the container 90 to spray cleaning agents on and/or at least partially clean the respective walls 93-96. Figures 2B and 2C show the same two steps in top view. During the extension of the extendable member 3 in the entry direction E, the one or more side detection sensors 71 may intermittently or continuously detect one or both side walls 93 and send corresponding detection signals to the control unit 7. The control unit 7 can subsequently determine the center between the side walls 95, 96 at the position of the cleaning tool 4 at different stages of the extension of the extendable member 3 in the entry direction E. The control unit 7 subsequently determines whether the cleaning tool 4 is still centered between the side walls 95, 96. The control unit 7 is configured, programmed or arranged to continuously control the drives 22 in the base 2 to adjust the lateral position of said base 2 towards the determined center between the side walls 95, 96 such that the cleaning tool 4 continuously remains in the center and/or close to the center line C of the container 90 between the side walls 95, 96. Alternatively, as schematically shown in figures 2B and 2C, the control unit 7 may be configured, programmed or arranged to control the drives 22 in the base 2 to adjust the lateral position of said base 2 only when the misalignment of the cleaning tool 4 with respect to the center of container 90 between the side walls 95, 96 exceeds a predetermined threshold value. Said threshold value may for example be set in the range of two to twenty centimeters.

Figures 1C, ID and IE show the steps of cleaning the leading end 92 of the container 90, specifically when using the cleaning tool 4 in the form of the washing head 40. Once the extendable member 3 is extended such that the third brush assembly 43 and the fourth brush assembly 44 contact the leading end 92 of the container 90, the extension stroke of the extendable member 3 in the entry direction E is completed. The washing head 40 is now ready to clean the leading end 92 of the container 90 prior to a retraction stroke of the washing head 40 in the retraction direction R. In figure 1C, when the washing head 40 first arrives at the leading end 92 of the container 2, the third brush assembly 43 and the fourth brush assembly 44 may be moved apart in the height direction H into contact with the bottom wall 93 and the top wall 94, respectively, at or near the leading end 92. The brushes 5 may be driven in rotation - if not rotating already. The third brush assembly 43 and the fourth brush assembly 44 may also be moved directly into the positions as shown in figure ID or IE .

Figure ID shows the situation in which the fourth brush assembly 44 has been moved downwards in the height direction H into close proximity to, at, above or directly above the third brush assembly 43 to clean the upper half of the leading end 92. Figure IE shows the situation in which both the third brush assembly 43 and the fourth brush assembly 44 have been moved upwards in the height direction H to allow the third brush assembly 43 to clean the lower half of the leading end 92. It will be apparent to one skilled in the art that alternatively, the third brush assembly 43 may first be moved upwards into close proximity to, at, below or directly below the fourth brush assembly 44 and that both brush assemblies 43, 44 may subsequently be downwards, which has substantially the same result.

In the step as shown in figure IF, the third brush assembly 43 and the fourth brush assembly 44 of the washing head 4 are moved in the height direction H away from each other towards and into contact with the bottom wall 93 and the top wall 94, respectively. The control unit 7 may be configured, programmed or arranged for automatically or autonomously positioning said brush assemblies 43, 44 relative to the bottom wall 93 and the top wall 94 based on detection signals from the bottom detection sensor 72 and the top detection sensor 73. By moving the third brush assembly 43 into a position in which the brush 5 thereof extends in the height direction H to a level below the lowest point of the brushes 5 of the first brush assembly 41 and the second brush assembly 42, the third brush assembly 43 can simultaneously clean the bottom wall 93, at least part of the side walls 95, 96 and the corners between the side walls 95, 96 and the bottom wall 93. Similarly, by moving the fourth brush assembly 44 into a position in which the brush 5 thereof extends in the height direction H to a level above the highest point of the brushes 5 of the first brush assembly 41 and the second brush assembly 42, the fourth brush assembly 44 can simultaneously clean the top wall 94, at least part of the side walls 95, 96 and the corners between the side walls 95, 96 and the top wall 94. In other words, with the brushes 5 of the third brush assembly 43 and the fourth brush assembly 44 maximally spaced apart in the height direction H, the height of the washing head 40 at the third brush assembly 43 and the fourth brush assembly 44 is greater than the first length XI of the brushes 5.

The movability and/or strategic positioning of the third brush assembly 43 and the fourth brush assembly 44 relative to the first brush assembly 41 and the second brush assembly 42 means that the washing head 40 according to the invention can be easily adapted to clean containers 90 with varying heights. In particular, containers 90 with heights in the range of the length XI of the brushes 5 of the first brush assembly 41 and the second brush assembly 42 in the height direction H to said length XI plus the extra height covered by the brushes 5 of the third brush assembly 43 and the fourth brush assembly 44 can be cleaned reliably. The extra height is preferably equal to the sum of the two radii of the brushes 5 of the third brush assembly 43 and the fourth brush assembly 44, which is the same as the second diameter D2 of one of said brushes 5, as shown in figure 6. In this particular example, the washing head 40 is capable of washing the entire height of containers 90 have a height in the range of two meters and fifteen centimeters to two meters and seventy centimeters. The third brush assembly 43 and the fourth brush assembly 44 can be positioned so that their rigid cores do not contact the bottom wall 93 and the top wall 94, respectively .

Figure IF schematically shows the cleaning tool 4 ready for the retraction stroke in the retraction direction R. During this retraction stroke, the control unit 7 may similarly control the position of the base 2 in response to the detection signals from the one or more side detection sensors 71 to keep the cleaning tool 4 centered between the side walls 95, 96. During the retraction stroke of the extendable member 3 in the retraction direction R, the rotation direction of the brushes 5 at the washing head 40 may be reversed to aid the flushing out of water, cleaning agents and/or dirt. This flushing out is promoted further by the downwardly sloping angle of the pit 81 towards the platform 82.

In the method above, it is assumed that the cleaning tool 4 can easily follow the position of the base 2 in the lateral direction T towards the determined center between the side walls 95, 96 without substantial friction. In order to reduce friction, the one or more wheels 63 of the cleaning tool 4 may be formed as one or more swivel wheels. Optionally, the extendable member 3 can be made relatively rigid to cause the cleaning tool 4 to follow the movements of the base 2 in the lateral direction T.

In practice however, the one or more wheels 63 are fixed to keep the cleaning tool 4 in the right track. This has the drawback that when the base 2 is moved in the lateral direction T as the cleaning tool 4 is extended into the container 90, corrections of the base 2 away from the side walls 95, 96 towards the determined center between said side walls 95, 96 actually cause a pivoting of the cleaning tool 4 in the opposite direction, thereby steering said cleaning tool 4 into the side wall 95, 96 from which the base 2 is moving away. Figures 3A-3H show steps of an alternative method in which this pivoting of the cleaning tool 4 is actually used advantageously to steer the cleaning tool 4 away from the side walls 95, 96 and keep it centered or substantially centered within the container 90.

As shown in figures 3A and 3B, the cleaning tool 4 is initially extended into the container 9 in the entry direction E without correction in the lateral direction L. In figure 3B, the cleaning tool 4 starts to approach the second side wall 96. The one or more side detection sensors 71 send signals representative of the off-center position of the cleaning tool 4 to the control unit 7. As shown in figure 3C, the control unit 7 subsequently controls the one or more drives 22 of the base 2 to move said base 2 in the lateral direction T away from the determined center between the side walls 95, 96. As the cleaning tool 4 tends to remain in the track of its one or more wheels 62, only the lateral position of the base 2 is adjusted and the cleaning tool 4 remains in its off-center position. The base 2 is now positioned at an angle behind the cleaning tool 4, considered in the extension direction E. This causes the cleaning tool 4 to pivot slightly towards the determined center position and/or into alignment with the center line C of the container 90. Hence, when the cleaning tool 4 is extended further into the container 90, as shown in figures 3D and 3E, it is actually steered towards and/or into alignment with the center line C of the container 90. This counter-steering of the base 2 behind cleaning tool 4 as the cleaning tool 4 is being extended into the container 90 has proven more effective than actually trying to force the cleaning tool 4 to move together with the base 2 in a respective lateral direction T.

The slight offset in orientation between the pivoted cleaning tool 4 and the base 2 can be absorbed by the extendable member 3, e.g. by manufacturing the extendable member 3 from a flexible material (for example aluminum) or by providing slight tolerances between the respective boom sections 32 of the extendable member 3. In particular, as shown in figures 3C, 3D and 3E, as more boom sections 32 are extended, the offset of the cleaning tool 4 with respect to the base 2 in the lateral direction T can be increased as more boom sections 32 can effectively absorb said offset.

It is noted that in this alternative method, the counter-steering of the base 2 behind the cleaning tool 4 does not apply during the retraction stroke in the retraction direction R, as shown in figures 3F, 3G and 3H . During the retraction of the cleaning tool 4, the base 2 is located in front of the cleaning tool 4, considered in the retraction direction R. Hence, the base 2 should now be moved in the lateral direction T towards the determined center between the side walls 95, 96 so that the cleaning tool 4 pivots towards and/or into alignment with the center line C of the container 90.

It is to be understood that the above description is included to illustrate the operation of the preferred embodiments and is not meant to limit the scope of the invention. From the above discussion, many variations will be apparent to one skilled in the art that would yet be encompassed by the scope of the present invention.

Claims

C L A I M S

1. Cleaning system (1) for cleaning the inside of a container (90), wherein the container (90) has a trailing end (91), a leading end (92) and a box like body formed by at least a first side wall (95) and a second side wall (96) extending in a longitudinal direction (L) between said trailing end (91) and said leading end (92), wherein the cleaning system (1) comprises a base (2) that is arranged to remain outside of the container (90) and an extendable member (3) that is extendable from said base (2) in an entry direction (E) through the trailing end (91) into the container (90) towards the leading end (92) thereof, wherein the cleaning system (1) is provided with one or more drives (22) for moving said base (2) in a lateral direction (T) perpendicular or substantially perpendicular to said entry direction (E) , wherein the extendable member (3) has a base end (31) that is connected to the base (2) and a distal end (32) that is arranged for holding a cleaning tool (4), wherein the extendable member (3) or the cleaning tool (4) is provided with one or more side detection sensors (71) for detecting the side walls (95, 96) of the container (90), wherein the cleaning system (1) further comprises a control unit (7) that is operationally connected to the one or more drives (22) and that is operationally connectable to the one or more side detection sensors (71) for receiving detection signals, wherein the control unit (7) is arranged for controlling the lateral position of the base (2) in the lateral direction (T) based on the detection signals from the one or more side detection sensors (71) .

2. Cleaning system (1) according to claim 1, wherein the control unit (7) is arranged for controlling the lateral position of the base (2) in the lateral direction (T) such that the cleaning tool (4) is centered between the two side walls (95, 96) .

3. Cleaning system (1) according to claim 1 or

2, wherein the control unit (7) is arranged for determining the center between the side walls (95, 96) at the location of the cleaning tool (4) and for moving the base (2) in the lateral direction (T) towards said determined center position .

4. Cleaning system (1) according to claim 1 or

2, wherein the control unit (7) is arranged for determining the center between the side walls (95, 96) at the location of the cleaning tool (4) and for moving the base (2) in the lateral direction (T) away from said determined center position during the extension of the extendable member (3) in the entry direction (E) .

5. Cleaning system (1) according to claim 4, wherein the control unit (7) is arranged for moving the base (2) in the lateral direction (T) towards said determined center position during a retraction of the extendable member (3) in a retraction direction (R) opposite to the entry direction (E) .

6. Cleaning system (1) according to any one of the preceding claims, wherein the control unit (7) is arranged for continuously controlling the lateral position of the base (2) in the lateral direction (T) based on the detection signals from the one or more side detection sensors (71) .

7. Cleaning system (1) according to any one of claims 1-5, wherein the control unit (7) is arranged for controlling the lateral position of the base (2) in the lateral direction (T) when the cleaning tool (4) is misaligned with respect to the center of container (90) between the side walls (95, 96) and said misalignment exceeds a predetermined threshold value.

8. Cleaning system (1) according to claim 7, wherein the threshold value is set in a range of two to twenty centimeters.

9. Cleaning system (1) according to any one of the preceding claims, wherein the cleaning system (1) comprises one or more guiding members (10) for guiding the movement of said base (2) in the lateral direction (T) .

10. Cleaning system (1) according to claim 9, wherein the one or more guiding members (10) are two rails (11, 12) extending mutually parallel in the lateral direction (T) .

11. Cleaning system (1) according to claim 10, wherein the base (2) is provided with wheels (21) for rolling over said rails (11, 12), wherein the one or more drives (22) are arranged for driving one or more of said wheels (21) .

12. Cleaning system (1) according to any one of the preceding claims, wherein the cleaning system (1) comprises the cleaning tool (4), wherein the one or more side detection sensors (71) are provided on the cleaning tool (4) and wherein the control unit (7) is operationally connected or connectable to the one or more side detection sensors (71) at said cleaning tool (4) .

13. Cleaning system (1) according to claim 12, wherein the cleaning tool (4) is a washing head (40), wherein the washing head (40) comprises a coupling member (6) for coupling the washing head (40) to the distal end (32) of the extendable member (3) and a first brush assembly (41) and a second brush assembly (42) for cleaning the first side wall (95) and the second side wall (96), respectively, in the lateral direction (T) and a third brush assembly (43) and a fourth brush assembly (44) for cleaning the bottom wall (93) and the top wall (94), respectively, in a height direction (H) perpendicular to the entry direction (E) and the lateral direction (T) , wherein each brush assembly (41-44) comprises a brush (5) and a brush holder (46) for holding the respective brush (5) with respect to the coupling member (6), wherein either the first brush assembly (41) and the second brush assembly (42) are located in front of the third brush assembly (43) and the fourth brush assembly (44) and are movable with respect to the coupling member (6) in the lateral direction (T) or the third brush assembly (43) and the fourth brush assembly (44) are located in front of the first brush assembly (41) and the second brush assembly (42) in the entry direction (E) and are movable with respect to the coupling member (6) in the height direction (H) .

14. Cleaning system (1) according to claim 13, wherein the third brush assembly (43) and the fourth brush assembly (44) are located in front of the first brush assembly (41) and the second brush assembly (42) in the entry direction (E) and are movable with respect to the coupling member (6) in the height direction (H) .

15. Cleaning system (1) according to claim 14, wherein the first brush assembly (41) and the second brush assembly (42) are fixed with respect to the coupling member (6) in the lateral direction (T) and/or the height direction (H) .

16. Cleaning system (1) according to claim 14 or

15, wherein the brushes (5) of the first brush assembly (41) and the second brush assembly (42) define a first outer width (Wl) of the washing head (40) in the lateral direction (T) and wherein the brushes (5) of the third brush assembly (43) and the fourth brush assembly (44) define a second outer width (W2) of the washing head (40) in the lateral direction (T) equal to or greater than the first outer width (Wl) .

17. Cleaning system (1) according to any one of claims 14-16, wherein the third brush assembly (43) is movable in the height direction (H) into a position in which the brush (5) of the third brush assembly (43) partially extends in the height direction (H) to a level below the lowest point of the brush (5) of the first brush assembly (41) and/or the second brush assembly (42).

18. Cleaning system (1) according to any one of claims 14-17, wherein the fourth brush assembly (44) is movable in the height direction (H) into a position in which the brush (5) of the fourth brush assembly (44) partially extends in the height direction (H) to a level above the highest point of the brush (5) of the first brush assembly (41) and/or the second brush assembly (42).

19. Cleaning system (1) according to any one of the preceding claims, wherein the container (9) has an inclined bottom wall (93), wherein the base (2) comprises a frame (20), wherein the base end (31) of the extendable member (3) is hingably coupled to the frame (20) so as to be pivotable about a pivot axis (P) parallel or substantially parallel to the lateral direction (T) , wherein the cleaning tool (4) is provided with one or more wheels (62) for running over the bottom wall (93) and following the inclination of the bottom wall (93) as the extendable member (3) pivots about the pivot axis (P) .

20. Cleaning system (1) according to claim 19, wherein the one or more wheels (62) are steerable, wherein the control unit (7) is operationally connected to the one or more wheels (62) to steer said one or more wheels (62) .

21. Cleaning system (1) according to claim 19 or 20, wherein the base (2) is further provided with a lifting member (24) for pivoting the extendable member (3) with respect to the frame (20) about the pivot axis (P) .

22. Cleaning system (1) according to any one of claims 19-21, wherein the cleaning tool (4) is provided with one or more load sensors (63) for measuring the load on the cleaning tool (4) .

23. Cleaning system (1) according to claims 21 and 22, wherein the one or more load sensors (63) are arranged for actuating the lifting member (24) when a threshold value for the load has been exceeded.

24. Cleaning system (1) according to claim 22 or 23, wherein at least one of the one or more load sensors (63) is a load cell that is located at the one or more wheels (62) of the cleaning tool (4) .

25. Method for cleaning the inside of a container (90) with the use of the cleaning system (1) according to any one of the preceding claims, wherein the method comprises the steps of operationally connecting the control unit (7) to the one or more side detection sensors (71) for receiving the detection signals and controlling the lateral position of the base (2) in the lateral direction (T) with the control unit (7) based on the detection signals from the one or more side detection sensors (71) .

26. Method according to claim 25, wherein the control unit (7) controls the lateral position of the base (2) in the lateral direction (T) such that the cleaning tool (4) is centered between the two side walls (95, 96) .

27. Method according to claim 25 or 26, wherein the control unit (7) determines the center between the side walls (95, 96) at the location of the cleaning tool (4) and moves the base (2) in the lateral direction (T) towards said determined center position.

28. Method according to claim 25 or 26, wherein the control unit (7) determines the center between the side walls (95, 96) at the location of the cleaning tool (4) and moves the base (2) in the lateral direction (T) away from said determined center position during the extension of the extendable member (3) in the entry direction (E) .

29. Method according to claim 28, wherein the control unit (7) moves the base (2) in the lateral direction (T) towards said determined center position during a retraction of the extendable member (3) in a retraction direction (R) opposite to the entry direction (E) .

30. Method according to any one of claims 25-29, wherein the control unit (7) continuously controls the lateral position of the base (2) in the lateral direction (T) based on the detection signals from the one or more side detection sensors (71).

31. Method according to any one of claims 25-29, wherein the control unit (7) controls the lateral position of the base (2) in the lateral direction (T) when the cleaning tool (4) is misaligned with respect to the center of container (90) between the side walls (95, 96) and said misalignment exceeds a predetermined threshold value.

32. Method according to claim 31, wherein the threshold value is set in a range of two to twenty centimeters .

33. Method according to any one of claims 25-32, wherein, in a situation in which the container (90) is positioned with its longitudinal direction (L) offset over an oblique angle (A) with respect to the entry direction (E) of the extendable member (3), the control unit (7) controls the lateral position of the base (2) based on the detection signals from the one or more side detection sensors (71) to compensate for this offset.

34. Method according to any one of claims 25-33, wherein the container (90) is provided with doors (97) for opening and closing the trailing end (92) of the container (90), wherein the method comprises the step of fixing the doors (97) relative to the surroundings in a position in which the doors (97) extend parallel or substantially parallel to the respective side walls (95, 96) .

35. Method according to any one of claims 25-30, wherein the container (90) has an inclined bottom wall (93), wherein the base (2) comprises a frame (20), wherein the base end (31) of the extendable member (3) is hingably coupled to the frame (20) so as to be pivotable about a pivot axis (P) parallel or substantially parallel to the lateral direction (T), wherein the cleaning tool (4) is provided with one or more wheels (62) for running over the bottom wall (93) and following the inclination of the bottom wall (93) as the extendable member (3) pivots about the pivot axis (P) .

36. Method according to claim 35, wherein the method further comprises the step of using a lifting member (24) to pivot the extendable member (3) about the pivot axis (P) and thereby raising or lowering the cleaning tool (4) relative to the base (2) and/or the container (90) .

37. Method according to claim 35 or 36, wherein the base (2) is provided with one or more load sensors (63) for measuring the load on the cleaning tool (4) and for actuating the lifting member (24) when a threshold value for the load has been exceeded. 0 0 0 0 0 0 0 0

RM/HZ