WO2018128547A1

WO2018128547A1 - Machine for movement along a surface

Info

Publication number: WO2018128547A1
Application number: PCT/NO2018/050001
Authority: WO
Inventors: Johannes T. HÅSKJOLD
Original assignee: Haaskjold Johannes T
Priority date: 2017-01-04
Filing date: 2018-01-02
Publication date: 2018-07-12

Abstract

Machine (100,200,201) comprising a housing (210), a brush (213) comprising a plurality of elongate, elastic elements, and an actuator (211) configured to: generate a vibrating motion in a the direction of a longitudinal axis (212) of the machine, or generate a cyclical, relative motion between a first part (21 Oa) of the housing (210) and a second part (21 Ob) of the housing. In an embodiment, a machine (100) for use in a pipe (90) comprises a housing (10), at least three drive units (20a-d) coupled to the housing (10) via a movable arm (21 a-d), an elastic element (30, 30a, b) arranged to urge the at least three drive units (20a-d) away from each other, a cleaning brush (40) connected to the housing (10) and operatively connected to an electric motor (50). There are also provided methods for cleaning a pipe (90).

Description

MACHINE FOR MOVEMENT ALONG A SURFACE

The present invention relates to a machine arranged for movement along a surface. In some embodiments, the machine is a pipe climbing machine, a chimney sweeping machine, or a machine which can move along horizontal, vertical and/or angled surfaces.

BACKGROUND In many industrial applications, there is a need for machines which can move along surfaces, for example along horizontal, vertical or angled surfaces. Such machines can be intended for carrying out operations such as inspection or repairs, or the machine can be arranged to move elements or equipment. For example, in chimneys or pipes it is common to carry out regular sweeping or cleaning, i.e. removal of soot or scaling along the inner surface of the pipe. Such sweeping or cleaning can be labour-intensive and involve health and safety risks, for example associated with working in heights. For other purposes there may often be a need for inspection, repair and the like in, for example, pipes and shafts which are difficult to obtain access to by human operators.

There is therefore a continuous need for improved solutions and methods for these types of operations. Known solutions which may be useful for

understanding the background include JP1 1344214A, CN205253671 U, CN205217536U, CN205128532U, CN102500588A, CN203917307U, US 2,917,762 and FI952806A.

The present invention has the objective to provide a machine with

improvements and advantages compared to known solutions. SUMMARY

In an embodiment, there is provided a machine comprising a housing, a brush fixed to the housing, where the brush comprises a plurality of elongate, elastic elements, and an actuator configured to: (i) generate a vibrating motion in a the direction of a longitudinal axis of the machine, or (ii) generate a cyclical, relative motion between a first part of the housing and a second part of the housing, where the first and second parts are movable in relation to each other in the direction of the longitudinal axis, and where a part of the brush is arranged on the first part and a part of the brush is arranged on the second part.

In an embodiment, there is provided a method for cleaning a pipe, the method comprising placing a machine in a compartment in a container unit, inserting the container unit into the pipe through an opening in the pipe, driving the machine out of the compartment and along the pipe.

In an embodiment, there is provided a machine for use in a pipe, the machine comprising: a housing, at least three drive units, each drive unit coupled to the housing via a movable arm, an elastic element arranged to urge the at least three drive units away from each other, and a cleaning brush connected to the housing and operatively connected to an electric motor.

In an embodiment, there is provided a method for cleaning a pipe, the method comprising inserting a machine into a pipe, urging at least three drive units against an inner surface of the pipe by means of the elastic element, driving the machine along the pipe by means of the at least three drive units while operating a cleaning brush by means of an electric motor.

The appended dependent claims and the detailed description below outline further embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

Illustrative embodiments will now be described with reference to the appended drawings, in which

Fig. 1 a illustrates a machine according to an embodiment,

Fig. 1 b illustrates a machine according to an embodiment,

Fig. 2 illustrates a machine according to an embodiment, Fig. 3 illustrates details of the machine shown in Fig. 2,

Fig. 4 illustrates details of an embodiment,

Fig. 5 illustrates details of an embodiment,

Fig. 6 illustrates details of the machine shown in Fig. 2,

Fig. 7 illustrates the machine shown in Fig. 2 in use,

Fig. 8 illustrates an aspect of the machine in Fig. 2 in use,

Fig. 9 illustrates an aspect of the machine in Fig. 2 in use, and

Fig. 10-16 illustrate machines according to further embodiments. DETAILED DESCRIPTION

Fig. 1 a, 1 b and 2 show different embodiments of a chimney sweeping machine according to the invention. The machine is arranged for use in a chimney 90 and comprises a housing 10 and three drive units 20a-c. (For the sake of clarity, only two drive units are shown in 1 b and 2.) Each drive unit 20a-c is fixed to the housing 10 by means of a movable arm 21 a-c, for example a linkage

mechanism. An elastic element, in this embodiment a spring 30, 30a, b, is arranged to urge the drive units 20a-c away from each other and outwardly towards the inner surface wall of the chimney 90. In the embodiments in Figs 1 a and 1 b, the spring acts in the machine's longitudinal direction (i.e. the

longitudinal direction of the chimney 90 when the machine is in use) and an outwardly force is generated by means of a linkage mechanism. In the embodiment shown in Fig. 2, a spring acts on each arm 21 a-c outwardly in a direction perpendicular to the machine's longitudinal direction.

A brush 40, driven by an electric motor 50, is arranged in conjunction with the housing 10. The brush 40 can be soft and flexible, and comprises a number of flexible, elongate wires (or threads) fixed to a rotatable brush shaft 41 . This allows the brush 40 to adapt to the chimney 90 by means of centrifugal force. Fig. 1 a shows the brush 40 in an operational state (i.e. rotating, whereby the centrifugal force brings the brush 40 into contact with the chimney 90), and Fig. 1 b shows the brush 40 in a non-operating state. Alternative designs for the brush 40 are also possible. The housing 10 comprises a battery 60 for operation of the electric motor 50. The battery 60 can be arranged inside the housing 10. This allows the battery 60 to be well protected against dirt or external loads. The battery 60 can, alternatively, be fixed to the housing 10 or to another part of the machine, externally. This could allow easier access for quick replacement of the battery 60.

The machine according to one of the embodiments shown in Figs 1 a, 1 b and 2 can thereby be driven along the chimney 90 by means of the drive units 20a-c, at the same time as the brush 40 is operated, and the machine can thereby sweep / clean the chimney or pipe.

The drive units 20a-c can be circular, oval or elongated. In the embodiment shown in Fig. 1 a, the drive units 20a-c are oval with a belt (not shown) arranged around the outer periphery of each drive unit 20a-c. In the embodiment shown in Fig. 1 b, the drive units are wheels 29a-c. In the embodiment shown in Fig. 2, the drive units 20a-c are elongate units.

Fig. 6 shows one of the drive units 20b from Fig. 2 in more detail. A belt 28 is arranged along the outer periphery of the drive unit 20b. The outer surface of the drive unit, i.e. the surface interacting with the inner wall of the chimney 90, can be linear or curved in a plane intersecting the longitudinal direction of the machine. By arranging the drive units with a curved profile, the motive performance may be improved as the curved surface interacts with the correspondingly curved inner surface of the chimney 90.

The electric motor 50 can be arranged to power the drive units 20a-c, in addition to powering the brush 40. This can, for example, be realised with a belt or chain transmission through the arms 21 a-c and to the drive units 20a-c. Alternatively, the drive units 20a-c can be equipped with own drive motors. This is illustrated in Fig. 6, where the drive unit 20b has an internal drive motor 22 with a control unit 23. Energy for powering the drive motor 22 can be provided from the battery 60 via electrical cables, for example through the arm 21 b. The other drive units 20a and 20c can be arranged equivalently. The battery 60 is preferably arranged such that, in an operational position of the machine in the chimney 90, the battery's centre of gravity lies lower than the coupling 24 between each drive unit 20a-c and the respective movable arm 21 a-c. This improves the machine's motive performance and stability during use.

The machine can further comprise a camera 80 and/or a light source 81 , such as a lamp, fixed to the housing 10 or on another location on the machine. This may ease external control of the machine, in that a picture or video signal may be sent to an operator.

The brush 40 can be configured with different directions of rotation. The brush shaft 41 can be arranged such that it, in an operational position of the machine in the chimney 90, extends parallel with the chimney's longitudinal direction, as shown in Fig. 1 a and 1 b. Alternatively, the brush shaft 41 can extend

perpendicularly on the chimney's 90 longitudinal direction. This is illustrated in Fig. 4, where two brushes are used for improved efficacy in a rectangular chimney 90.

The brush 40 can be arranged above or below the drive units 20a-c. Fig. 1 a and 1 b illustrate an embodiment in which the brush 40 is arranged above the drive units 20a-c, while Fig. 2 illustrates an embodiment where the brush 40 is arranged below the drive units 20a-c. (The brush 40 is illustrated only schematically in Fig. 2, but can have the same design as the brush shown in Figs 1 a and 1 b, as that shown in Fig. 4, or a different design.)

The brush 40 is advantageously releasably connected to the housing 10, e.g. by means of a quick-release coupling. This allows quick exchange of the brush, for example to adapt the machine for best possible efficacy in chimneys of different size, or for sequentially using different types of brush in the cleaning of a chimney. In one embodiment, shown in Figs 2 and 3, the machine has a connector unit 1 1 fixed to the housing 10, where each arm 21 a-c is releasably connected to the connector unit 1 1. The connector unit 1 1 can, for example, be designed as a plate or disc with recesses for fixing each arm 21 a-c, and may for this purpose have a quick-release coupling for connecting the arms, as well as a connector for energy supply to a drive motor 22 (see Fig. 6) in each drive unit 20a-c. If the machine is powered electrically, this may be an electric connector.

In one embodiment, the connector unit 1 1 has four connectors 12a,b,d,f (see Fig. 3), and each connector 12a,b,d,f is arranged for holding one arm 21 a-d. The four connectors 12a,b,d,f are arranged with 90 degree spacing around the connector unit 1 1 , for example around an outer periphery of a disc which makes up the connector unit 1 1 . Alternatively, or additionally, the connector unit 1 1 can have three connectors 12a,c,e arranged for holding a movable arm 21 a-d, where the three connectors 12a,c,e are arranged with 120 degree spacing around the connector unit 1 1 .

This allows the machine to be configured for varying pipes or chimneys, for example in that different arms can be used for chimneys of different size.

Further, this may allow the machine to be used in both round and square or rectangular chimneys, for example could three drive units be sufficient for use in circular chimneys while four could be necessary in rectangular chimneys.

In one embodiment, illustrated in Fig. 5, the machine is arranged in a

rectangular chimney 90. In this embodiment, the machine has four drive units 20a-d and four movable arms 21 a-d, and the four arms 21 a-d have pairs of arms with different length. This improves the efficacy of the machine and its operation, for example in rectangular chimneys. Fig. 7 illustrates a machine in use in a chimney 90. The machine can be brought into the chimney 90 by pressing the drive units 20a-d together and entering the machine into the chimney 90 through a cleaning door 91 . By having movable, spring-tensioned arms 21 a-d, the machine can be entered into the chimney 90 from below and through a cleaning door 91 in the lower part of the chimney 90 which has a smaller opening than the cross section of the chimney 90.

When the machine is entered and positioned in the chimney 90, each drive unit 20a-d is urged towards the inner surface of the chimney 90 by means of the respective elastic element 30, i.e. the spring. The machine can then be moved along the chimney 90 by means of the drive units 20a-d at the same time as the brush 40 is operated by the electric motor 50. The machine may further comprise an electronic control unit 82 configured to control the drive units 20a-d and the electric motor 50. The control unit 82 can be connected to an external control unit (not shown), for example via a wireless data link. This allows control of the machine of an external operator.

Alternatively, or additionally, the control unit 82 can be arranged to receive a signal via an operator panel 83 and start the drive units 20a-d and the electric motor 50 at a pre-determined time after having received the signal. This allows the machine to be placed in a chimney 90 with a time delay before the machine starts, for example to close the cleaning door 91 or other openings. The machine can be actively controlled by an operator, for example based on signals from the camera 80. The control unit 82 can, for this purpose, be arranged to send a picture signal from the camera 80 to the external control unit. The picture signal can thus assist the operator in the operation of the machine and/or be used for inspection of the chimney. Alternatively, the machine can through the control unit 82 be configured to move a predetermined distance upwards in the chimney 90, and then return. Alternatively, the machine can be configured to move upwardly in the chimney 90 until it meets some resistance, for example a chimney cap, and then return. The control unit 82 can further comprise an automatic stabiliser, such as a mercury switch, to align the machine if it is incorrectly positioned in the chimney, for example leaning or angled. This can be achieved by the control unit 82 being arranged to start/stop the relevant drive unit 20a-d which is necessary to align the machine. Fig. 8 shows another possible embodiment of the machine shown in Fig. 2, where each drive unit 20a-d is rotatably fixed to the movable arm 21 a-d via a respective coupling 24a, b. This allows the drive unit 20a-d to rotate freely about the coupling 24b. This rotation can be unlimited, or limited to a given angular space, such as ±30 degrees from the drive unit's ordinary position. This gives the advantage that irregularities in the chimney 90 can be better handled by the machine, such as a side pipe 92 extending a given distance into the chimney 90. Fig. 8 illustrates how a drive unit 20b in such a case can rotate about the coupling 24b to better navigate past the side pipe 92.

The size and length of the drive units 20a-d are preferably arranged such that these can pass any side pipes without entering into these or getting stuck. Fig. 9 illustrates an embodiment of a chimney sweeping machine in use in a chimney 90. In this embodiment there is a collection funnel 93 arranged in the lower part of the chimney 90, below the machine 100. A pipe 94 can be used in conjunction with the collection funnel 93, where the pipe 94 extends out of the chimney 90 and to a container 95 outside the chimney 90. The collection funnel 93 and part of the pipe 94 can be placed into the chimney through the cleaning door 91 after the machine has been placed in the chimney 90, and the pipe 94 can extend out through the cleaning door 91 during use. In this way, soot etc. which has been removed can be collected and disposed of in an appropriate manner.

In further embodiments, illustrated in Figs 10-15, there is provided a machine for movement along a surface. In the embodiments in Figs 10-15, the machine is illustrated as a pipe climbing machine 200 and/or a chimney sweeping machine 201 , however it should be understood that the machine according to the invention is not limited to these embodiments and can alternatively be a machine, for example, for use in a different type of narrow space, shaft or the like, or for use on horizontal or angled open surfaces. In Figs 10-14, there is shown a pipe climbing machine 200 comprising a housing 210 and a brush 213 comprising a plurality of elongate, elastic elements fixed to the housing 210. The elongate elements can, for example, be spring steel or plastic. These are fixed to the housing outwardly with an angle relative to the longitudinal axis 212 of the machine. The angle may be 90 degrees, or it can be a different angle, for example could the elements have a small angle from the perpendicular in their fixation point on the housing 210. The elements may be linear or curved in their non-tensioned state. Curved elements can for example be advantageous for use in horizontal pipes or (where the machine is not a pipe climbing machine) for use on horizontal or lightly angled surfaces.

An actuator 21 1 is arranged in the housing 210. In the embodiments illustrated in Figs 10-12 and 14, the actuator is arranged to create a cyclical (repetitive, at least partly linear) relative movement between a first part 210a of the housing 210 and a second part 210b of the housing 210. The first and second parts 210a,b are capable of relative movement in relation to each other, in the longitudinal direction / longitudinal axis 212, and a part of the brush 21 1 is arranged on the first part 210a and a part of the brush 21 1 is arranged on the second part 210b.

The machine 200 can be a chimney sweeping machine, however the machine 200 can alternatively or additionally be a machine to carry equipment for other purposes, such as pipe inspection, installation of tools or equipment in pipes (such as measurement or monitoring equipment), repairs, etc.

Fig. 10 shows an embodiment where the first part 210a and the second part 210b are arranged side by side along an axis which is perpendicular on the machine's 200 longitudinal axis 212. When the machine 200 is installed in the pipe 90, the elastic elements in the brush 213 are lightly bent in the backwards direction (relative to the longitudinal direction of the machine) and the end of the elements are urged against the pipe wall, for example due to a larger diameter of the brush compared to the inner diameter of the pipe, or because the brush 213 is angled. For example, the elastic elements can have an angle against the pipe wall which is between 15 and 60 degrees; however other angles are also possible.

In a cyclical, back-and-forwards motion between the first and the second parts 210a,b, the brush 213 can withstand a larger force downwards compared to the resistance force required to "pull" the brush 213 upwards along the pipe 90. This is due to the friction from the ends of the elastic elements being higher in the downwards direction due to the angle against the pipe wall, which creates more support / more friction. A cyclical movement between the first and second parts 210a,b therefore allows the machine 200 to "climb" in the pipe 90.

The machine can be a chimney sweeping machine and comprise one or more of the individual elements described in relation to the embodiments described above, for example the brush 40, camera 80, control system 82, battery 60, etc. These will not be described again here, however it is to be understood that any combination of individual components are possible and intended. The brush 40 can, for example, be arranged above or below the housing 10, as shown in Figs 1 a, 1 b and 2. Figs 1 1 A and 1 1 B shows another embodiment which is in some respects similar to that shown in Fig. 10. The first and the second parts 210a,b can be

distributed along the circumference of the machine 200, for example can the first part 210a be arranged on two opposite sides and the second part 210b be arranged on two opposite sides. Arranging the brush 213 in such "sectors" around the circumference of the machine gives more stability and reduces or prevents swaying of the machine during use.

Fig. 12 shows another embodiment, where the first and second parts 210a,b are arranged with a distance between each other in the longitudinal direction of the machine 200. The actuator 21 1 is in this embodiment arranged between the first and second parts 210a,b. This embodiment can give better stability in certain applications through a larger distance between the brush 213 on each side of the first and second parts 210a,b, which among other things gives more stability against side forces which may act on the machine 200. The brush 213 may further be arranged on releasable elements which may be exchanged, for example by means of a quick-release coupling. This allows different types of brush 213 to be used in different pipes or for different purposes, for example having a length or stiffness on the elastic elements according to specific requirements.

The actuator 21 1 can, for example, be a solenoid, a linear electric motor, a rotating electric motor with a crank system, or another type of actuator which is capable of generating relative motion between the first and second parts 210a,b.

Figs 13A and 13B show another embodiment. In this embodiment, the housing 10 comprises a vibration mechanism which generates a vibrating motion in the housing 10 in the longitudinal direction of the machine. This will lead to individual elastic elements in the brush 213 "slipping" and moving a small distance upwards on the pipe wall, and one can achieve a climbing motion of the machine 200 upwards in the pipe. The vibration mechanism can, for example, be an eccentric weight arranged on a motor shaft which is powered by the battery 60 or by an external power supply. The axial vibration force can be arranged to be larger than the sum of friction and the gravitational forces of the machine, but less than the friction "backwards" or downwards in the pipe. In this way, forward motion can be generated by the vibration mechanism. In this embodiment, the machine can be arranged such that the brush 213 can be replaced to give a configuration suitable for any given application (for example, the angle of the surface on which the machine operates). The brush 213 may, for example, be fixed to the machine by means of a quick-release coupling or an easily releasable bolt connection for this purpose. Other arrangements for replacement of the brush 213 may also be used. Fig. 14 illustrates another embodiment having a vibration mechanism, but with a similar brush configuration to that shown in Fig. 12.

Fig. 15 shows another embodiment, wherein the machine 200 is a chimney sweeping machine 201 and a brush 40 is arranged between the first and the second parts 210a,b of the housing 210. In this embodiment, the actuator 21 1 is arranged partly in the first part 210a and partly in the second part 210b.

The embodiment shown in Fig. 15 also comprises a line 215 fixed to the back end 216 of the machine 200. Such a line 216 can be used together with any of the embodiments described above as well. By means of the line 216, an operator can pull the machine 200 backwards and out of a pipe 90 if necessary. Further, the line 216 allows a reversal of the direction of motion of the machine 200. By pulling the machine 200 a short distance backwards with the line 216, the elastic elements in the brush 213 will change their angle ("bent upwards" instead of "bent downwards") such that relative motion between the first and second housing parts 210a,b will give a motion in the opposite direction, but otherwise equivalent to that described above. This allows the machine to work its way along a pipe 90 towards an end therefor, where an operator via the line 215 reverses the direction of motion and the machine 200 works its way back. The machine may, for example, be actively cleaning the pipe or carrying out other operations in both directions.

By a machine 200 according to embodiments described above, one achieves a operationally reliable system which is less sensitive to the specific design and inner progress of the pipe, for example deposits of soot in the pipe 90, side pipes extending from the pipe 90 (see Fig. 8), or the like. The brush 213 can, for example, be arranged on a replaceable unit such that different brushes 213 (e.g. with different length elastic elements) can be used according to a given requirement. By using a high number of elastic elements, good grip is achieved along the side walls of the pipe 90, with lower risk that the machine 200 gets stuck, and this also allows the machine 200 to carry a larger load, e.g. heavier cleaning equipment or other equipment, and/or to operate in longer pipes. In an embodiment, illustrated in Fig. 16, there is provided a container unit 101 , a so-called "garage unit", for a machine 100,201 . The machine 100,201 can be any of the machines described above. The garage unit 101 comprises a space / a garage 102 for the machine 100,201 . In use, the machine 100,201 can be placed in the garage 102, as shown on the right hand side in Fig. 10, and the garage unit 101 can be inserted into the cleaning door 91 of the pipe 90. The garage unit 101 is thus placed in the pipe 90, as shown to the left in Fig. 10. The garage unit 102 has an opening which the machine 100,201 can move out through, such that when the garage unit 102 is placed in the pipe 90, the machine 100,201 can start moving along the pipe 90, as illustrated in the upper part of Fig. 10, on the left hand side.

In one embodiment, the garage unit 102 can make up a collection container at a lower part of the pipe 90, which collects e.g. ashes, soot or other debris which the machine 100,201 removes from the pipe 90. A tube 94 can be arranged with the garage unit 102 to lead the debris out of the pipe 90 through the cleaning door 91 . In one embodiment, there may be a sealing element 103 arranged between the tube 94 and the cleaning door 91 . By means of the container unit 101 it is possible to operate the equipment in a cleaner manner, improving the collection of debris, as well as providing a more reliable and simple handling of the machine 100,201 .

By means of embodiments of the present invention, a number of advantages can be achieved, such as enhanced safety during sweeping or cleaning of chimneys or pipes, improved effectiveness, and reduced risk of fire or other undesirable consequences of debris or deposits accumulating in chimneys or pipes. The different embodiments described above and their individual components can be combined in a variety of optional configurations, to provide a machine suitable for given requirements. The invention is not limited to the embodiments described; reference should be had to the appended claims.

Claims

A machine (100,200,201 ) comprising

a housing (210)

a brush (213) fixed to the housing (210), where the brush (213) comprises a plurality of elongate, elastic elements,

an actuator (21 1 ) configured to:

(i) generate a vibrating motion in a the direction of a

longitudinal axis (212) of the machine, or

(ii) generate a cyclical, relative motion between a first part

(210a) of the housing (210) and a second part (210b) of the housing, where the first and second parts (210a,b) are movable in relation to each other in the direction of the longitudinal axis (212), and where a part of the brush (213) is arranged on the first part (210a) and a part of the brush (213) is arranged on the second part (210b).

A machine according to the preceding claim with alternative (ii), where the first and second parts (210a,b) are arranged:

- side by side along an axis which is perpendicular to the longitudinal axis (212), or

- spaced along the longitudinal axis (212).

A machine according to the preceding claim, comprising a cleaning brush (40) operatively connected to an electric motor (50).

A machine according to the preceding claim, wherein the cleaning brush (40) is arranged between the first (210a) and the second (210b) part.

A machine according to any of the two preceding claims, wherein the cleaning brush (40) comprises a plurality of flexible, elongate threads fixed to a rotatable brush shaft (41 ), and wherein the brush shaft (41 ): is arranged parallel to the longitudinal axis (212), or is arranged perpendicularly to the longitudinal axis (212).

6. A machine according to any preceding claim, comprising an electronic control unit (82) configured for controlling the actuator (21 1 ). 7. A machine according to the preceding claim, comprising a line (215) fixed to a rear end (216) of the machine and arranged for pulling the machine backwards in a pipe (90).

8. A machine according to any preceding claim, wherein the brush (213) is fixed to the housing (210) with a releasable coupling.

9. A machine according to any preceding claim, wherein the brush (213) is arranged in a plurality of sectors around a circumference of the machine, wherein the sectors is movable relative to each other in a direction parallel to the longitudinal axis (212).

10. A machine according to any preceding claim, wherein the machine is a pipe climbing machine (200) or a chimney sweeping machine (100,201 ). 1 1 . A method for cleaning a pipe (90), the method comprising

placing a machine (100,201 ) in a compartment (102) in a container unit (101 ),

inserting the container unit (101 ) into the pipe (90) through an opening (91 ) in the pipe (90),

driving the machine out of the compartment (102) and along the pipe

(90).

12. A method according to the preceding claim, comprising

collecting debris from the pipe (90) in the compartment (102), and leading the debris out of the pipe (90) through a conduit (94) connected to the compartment (102).

13. A method according to the preceding claim, compris arranging a sealing element (103) between the conduit (94) and the opening (91 ).

14. A machine (100) for use in a pipe (90), the machine comprising:

a housing (10),

at least three drive units (20a-d), each drive unit (20a-d) coupled to the housing (10) via a movable arm (21 a-d),

an elastic element (30,30a, b) arranged to urge the at least three drive units (20a-d) away from each other,

a cleaning brush (40) connected to the housing (10) and operatively connected to an electric motor (50).

15. A machine (100) according to the preceding claim, further comprising a battery (60) for operation of the electric motor (50).

16. A machine according to the preceding claim, wherein the battery (60) is arranged such that, in an operational position of the machine (100) in the pipe (90), the battery's (60) centre of gravity is located lower than a coupling (24a, b) between each drive unit (20a-d) and its respective arm (21 a-d).

17. A machine (100) according to any of claims 14-16, where each drive unit (20a-d) comprises wheels (29a, b) or wherein each drive unit (20a-d) comprises belts (28).

18. A machine according to any of claims 14-17, wherein

the electric motor is arranged to drive the drive units (20a-d), or wherein each drive unit (20a-d) comprises a drive motor (22). 19. A machine according to any of claims 14-18, wherein the cleaning brush (40) comprises a plurality of flexible, elongate threads fixed to a brush shaft (41 ), and wherein the brush shaft (41 ) is arranged such that, in an operational position of the machine (100) in the pipe (90), the brush shaft (41 ) is arranged parallel to a longitudinal direction of the pipe (90), or is arranged perpendicularly to the longitudinal direction of the pipe (90).

20. A machine according to any of claims 14-19, wherein each drive unit (20a-d) is rotatably coupled to its respective arm (21 a-d) via a coupling (24a,b).

21 . A machine according to any of claims 14-20, wherein the machine

comprises four drive units (20a-d) and four movable arms (21 a-d), and wherein the arms (21 a-d) comprise pairs of arms (21 a-d) with different length.

22. A machine according to any of claims 14-21 , comprising a connector unit (1 1 ) fixed to the housing (10), wherein each movable arm (21 a-d) is releasably connected to the connector unit (1 1 ).

23. A machine according to the preceding claim, wherein

the connector unit (1 1 ) has four connectors (12a-f) and each connector (12a-f) is arranged for holding one of the movable arms (21 a-d), and where the four connectors (12a-f) are distributed with 90 degree spacing around the connector unit (1 1 ), and/or

the connector unit (1 1 ) has three connectors (12a-f) and each connector (12a-f) is arranged for holding one of the movable arms (21 a-d), and where the three connectors (12a-f) are distributed with 90 degree spacing around the connector unit (1 1 ).

24. A machine according to any of claims 14-23, comprising an electronic control unit (82) arranged to control the drive units (20a-d) and the electric motor (50).

25. A machine according to the preceding claim, wherein the control unit (82) is arranged to:

receive a signal via a user interface (83), and start the drive units (20a-d) and the electric motor (50) a pre-determined time after having received the signal.

26. A method for cleaning a pipe (90), the method comprising

inserting a machine (100) according to any of claims 14-25 into the pipe

(90),

urging the at least three drive units (20a-d) against an inner surface of the pipe (90) by means of the elastic element (30),

driving the machine along the pipe (90) by means of the at least three drive units (20a-d) while operating the cleaning brush (40) by means of the electric motor.

27. A method according to the preceding claim, wherein the step of inserting the machine (100) into the pipe (90) comprises pressing the at least three drive units (20a-d) together and inserting the machine (100) into the pipe (90) through a cleaning door (91 ).

28. A method according to any of claims 26-27, further comprising arranging a collection funnel (93) in the pipe (90).

29. A method according to the preceding claim, further comprising arranging a tube (94) connected to the collection funnel (93), wherein the tube (94) leads out of the pipe (90) to a container (95) outside the pipe (90).