ROBOTS FOR TRENCHLESS PIPING AND SHAFT REHABILITATION

Description

[0001] The invention relates to a robot for trenchless pipeline and shaft rehabilitation with at least two expansion segments, each with a self-locking expansion mechanism with at least one double scissor stroke for spreading and pressing against the pipe or shaft wall, an expansion segment as the foremost segment, wherein the expansion mechanism for actuating the double scissor stroke has a spindle which is rotatably mounted in the expansion segment in the direction of movement of the robot, and wherein all segments are coupled to each other via connecting pieces.

[0002] The robot is specifically designed for opening hardened liner tubes, inspecting and cleaning pipelines, uncovering blockages and removing deposits from pipes.

[0003] Robots are needed for the maintenance of sewage pipes, drinking water pipes, and ventilation shafts to perform work without excavating the pipe or shaft. Typically equipped with an image sensor and a tool, usually a milling cutter, these robots have so far been manually controlled. This was primarily necessary because these devices could not determine the position of individual components or control the actuators with sufficient precision. By using electric motors for precise positioning and encoders, for example, to accurately determine the position of the moving components, it is possible to automate movement sequences. For instance, a cruise control can be used to enforce continuous forward or backward movement, or a specific point in the pipe can be targeted if the robot's position within the pipe can be measured.There are some applications where automating the robot can be useful, such as the independent removal of deposits from pipe walls using a brush attachment.

[0004] A robot of the type mentioned above is known from US Patent 2016 / 018045 A1. This robot has a modular robot assembly with a cluster of individual pod assemblies configured to fit, for example, inside a large-diameter, circular pipe. A particular assembly comprises a central pod assembly and three outer pod assemblies alternately attached to the side walls of the central pod assembly. The three outer pod assemblies are drive pod assemblies, each carrying a crawler drive for moving the modular robot assembly. The outer pod assemblies are equipped with double scissor lifters. The central pod assembly incorporates functionality specifically designed for a particular repair, maintenance, assembly, or other function to be performed within the respective pipeline environment.The modular robot arrangement can comprise several interconnected clusters of individual pod arrangements.

[0005] CN 214 119 373 U relates to a robot for detecting variable-diameter pipes, which exhibits high efficiency when dealing with changing diameters and is easy to use. It features a main body frame equipped with a detection mechanism for identifying the inside of a pipe. The walking mechanism comprises pivot arms that are articulated at intervals around the circumference of the main body frame and have rollers at their leading ends.

[0006] The robot known from FR 3 016 674 A1 is equipped with a thrust device that moves in a line by longitudinal extension and retraction. It has a front module and a rear module, each fitted with friction elements that are inserted in a direction perpendicular to the longitudinal movement of the thrust device. An extendable and retractable actuator is arranged between the two modules.

[0007] The friction elements that can be used have arms that are equipped at one end with curved shoes that can be placed against the pipe wall and are articulated to the modules at their second end.

[0008] FR 2 917 153 A1 relates to a robot for moving a package, in particular containing nuclear waste, in a landfill pipe, wherein this robot comprises a front part and a rear part connected to each other by a central actuator capable of moving these parts towards and away from each other, wherein the front part and the rear part each have a circular contour provided with a toric cylinder, for example an inflatable toric seal, wherein each part can be blocked in the pipe by inflating its toric cylinder. The robot has a hydraulic unit capable of inflating and deflating the front toric cylinder and the rear toric cylinder with a fluid, as well as a control unit for the hydraulic unit and a central actuator.

[0009] US patent 2021 / 301967 A discloses a robot comprising a body with first and second segments configured to move relative to each other. Each segment has at least two legs. The legs are not parallel to the body and are configured to extend outwards and retract inwards relative to the body, enabling movement within a tube.

[0010] EP 0 856 118 B1 relates to an internal pipe manipulator for inspecting or processing the inner surface of a pipe. In this manipulator, a multi-section swivel arm is slidably mounted on a chassis that moves within the pipe, along a longitudinal axis of the chassis. The swivel arm carries a system carrier for a testing system or a working device at its free end and can be at least partially retracted into the interior of the chassis. A threaded spindle, rotatably mounted within the chassis, is provided for moving the swivel arm. The swivel arm is mounted on this spindle.

[0011] CN 112 128 512 B discloses a pipeline robot and pipeline inspection equipment. The pipeline robot comprises a main machine body, a vision module, a drive module, and a control module. The vision module is mounted on the main machine body. The drive module comprises two drive motors and drive wheelsets, which are rotatably mounted on the two sides of the main machine body. The two drive motors are in transmission connection with the two drive wheelsets. The drive wheels of the drive wheelsets are in transmission connection via a transmission piece on the outside of the main machine body.

[0012] A power pipeline robot with a main shaft and a control system is known from CN 209 557 886 U. Three crawler devices are arranged circumferentially on the outer surface of the main shaft. A scoop for removing foreign objects is located at one end of the shaft. A position adjustment device is located at the other end of the shaft.

[0013] From WO 2012 / 112835 A1, a pipe robot made of interchangeable modules is known, including a frame module and at least one of a first shoulder module, a first joint module, and a first hand module. A module control unit for embedding intelligence is arranged in each of the interchangeable modules. Each of the interchangeable modules has a proximal end, a middle end, and a distal end. Each of the module control units is configured to send and receive signals from each of the interchangeable modules.

[0014] From WO 2021 / 052868 A1, a sewer exploration robot is known which consists of two cylindrical segments with retractable support modules and a positioning system arranged between these segments. Each support module comprises three retractable scissor strokes, offset from each other by 60° around the circumference of the respective segment. These scissor strokes are 1.5 times the length of the scissor stroke and extend radially from the segments, so that their stroke is limited by the diameter of the segments. The positioning system, which allows the relative position of the two segments to be adjusted, has at least one pair of linear actuators oriented parallel to the longitudinal axis of the robot. These actuators are coupled to one of the segments to position that segment relative to the other segment by means of independent translational movements.

[0015] The invention is based on the objective of providing a robot for trenchless pipeline and shaft rehabilitation which can be used in pipelines and shafts of different dimensions and can be moved precisely within them, can be supported particularly well and reliably on the inner wall of the pipeline or shaft and can be positioned centrally at any point in the pipe or shaft in order to carry out rehabilitation work.

[0016] The problem is solved with a robot according to claim 1, which has at least one feed segment between two extension segments, wherein each feed segment has a self-locking feed mechanism for increasing or decreasing the distance between the two extension segments coupled to the feed segment, wherein the feed mechanism has a piston which is mounted at one end of a connecting piece and can be moved back and forth by a spindle drive.

[0017] The robot's overall design, consisting of at least two extension segments with double scissor strokes, each with a feed segment positioned between the extension segments and one extension segment as the leading segment, enables both a "worm-like" movement of the robot within the pipe or shaft and precise positioning of the leading segment at a specific point. The double scissor strokes in the extension segments, and their orientation and actuation via spindles running in the robot's direction of movement, allow for a large stroke, making the robot suitable for use in pipes and shafts of varying dimensions. Furthermore, the double scissor strokes at their outer ends allow for the arrangement of support elements, such as feet, parallel to the robot's direction of movement, ensuring particularly good and reliable support of the double scissor strokes against the inner wall of the pipe or shaft.The feed segments enable the robot to move step by step in the pipe or shaft by simply moving the connecting pieces.

[0018] In a particularly preferred embodiment, the expansion segments each have two double scissor strokes that can be extended in opposite directions and are actuated together via the spindle. This feature is particularly advantageous for using the robot in pipelines and shafts with especially large inner diameters.

[0019] According to the invention, all segments of the robot are coupled to one another by connecting pieces, which are in particular stiffened and torsionally rigid hose sections. Such connecting pieces between the segments make the robot extremely flexible for movement through bends in the pipe or shaft.

[0020] In a further advantageous embodiment of the robot, a lifting device with a head mounted on the extension segment forming the foremost segment and equipped with at least one tool and / or measuring device is provided, wherein the lifting device is designed in particular for rotating and / or raising and lowering the head, so that the head can be positioned with particular precision, for example for carrying out milling operations.

[0021] Preferably, the lifting device has a drive element and a locking device, wherein the drive element is connected to the locking device by means of a connecting shaft, so that the lifting device can be controlled accordingly and, if necessary, also unlocked, for example to prevent a defect in the event of externally acting forces.

[0022] According to another preferred embodiment of the robot, two extension segments, coupled to each other by a connecting piece, are attached to the lifting device. In this way, the front part of the robot can be positioned in a particularly stable and optimally centered manner at the desired location.

[0023] In this regard, it is also particularly advantageous if these two successive expansion segments, and any further planned successive expansion segments, are rotatable relative to each other. Such mutual rotation is especially advantageous for the two expansion segments adjoining the lifting device.

[0024] In a further preferred embodiment of the robot, it is provided that it has at least two feed segments, each located between two extension segments. In this way, the stepwise, "worm-like" movement of the robot is virtually smoothed, so that, for example, by controlling the foremost extension segment, this segment can be moved smoothly, and in particular the head can be moved back and forth evenly and continuously.

[0025] The rearmost or back component of the robot is in particular a plug segment to which a main connecting plug of a supply cable, which is preferably designed in the form of a sliding cable, can be plugged.

[0026] A particularly advantageous design of the robot is one with an emergency power supply including electronics, preferably integrated into the connector segment. This emergency power supply is designed to temporarily maintain power to the internal control components in the event of a power failure, enabling the robot to retract the double scissor strokes of the self-locking expansion segments, the self-locking feed mechanisms of the feed segments, and, if necessary, to unlock the lifting device. This ensures that the robot can be removed from the pipe or shaft without damage in the event of a power outage.

[0027] The tools and / or measuring devices mounted on the head of the robot include at least one of the following: an ultrasonic measuring device for measuring the thickness of the pipe wall, a laser measuring device for 3D measurement of the pipe and deposits, a strong light source for spot curing of a resin hose, a laser for cutting away material or engraving the pipe wall, a motor with a brush or a milling head.

[0028] Additionally, it is advantageous to have an image sensor mounted on the head facing the tool(s) to transmit a live image to a control unit and to position the robot at a specific location.

[0029] A particularly user-friendly version of the robot is one in which a programmed control is provided for automatically approaching a defined point in the pipe or shaft system and / or for autonomously milling or grinding pipe or shaft walls in previously defined areas.

[0030] The invention is described in more detail below with reference to the figures. These figures show Fig. 1 a view of one design variant of the robot, Fig. 2 a view of another variant of the robot, Fig. 3 an exploded view of the mechanism of a lifting device, Fig. 4 a view of the mechanism for locking or unlocking a moving part of the lifting device, Fig. 5 a view of the mechanism for the expansion of expansion segments and Fig. 6 a complete step of the robot's worm-like locomotion.

[0031] The robot has one head 1 ( Fig. 1 , Fig. 2 ) on which various tools and measuring devices can be mounted, such as an ultrasonic measuring device for measuring the pipe wall thickness, a laser measuring device for 3D measurement of the pipe and deposits including precise damage images, a powerful light source for spot curing, e.g., of a resin hose, a laser for cutting away material or engraving the pipe wall, or a motor with a brush or milling head. Ideally, it also always contains an image sensor with a view of the tool. The image sensor and the live image transmitted to the control unit are necessary not only for controlling the tool but also for positioning the robot at the correct location inside the pipe.

[0032] The head 1 is attached to a lifting device 2, which, in combination with a rotary device, e.g., in segment 3 coupled to the lifting device 2, enables control of the head 1 in at least two axes. Depending on the required force, the lifting device 2 can be designed in different ways and include different types of gears. In the Fig. 3 In the illustrated embodiment, the lifting device 2 consists of two assemblies: a rigid and a movable part. Rotation between the parts is enabled by a worm gear 17, which is self-locking and would therefore jam if the robot were forcibly pushed into or pulled out of the pipe without the lifting device 2 being controlled accordingly, adapted to the geometry of the pipeline, especially in bends. Therefore, the non-driven part contains a locking device 9, which can decouple the shaft 14 and the part 12 or 15 housing it, so that the parts remain connected, but the shaft 14 is allowed to rotate freely, or rather, its rotation is prevented from being transmitted to the part until it is re-locked. The lifting device 2 can be disengaged by external forces, such as those exerted by a robot, while in the unlocked state.when moving the robot in the pipe at bends and branches, it can be moved without the self-locking worm gear 17 being loaded or the shaft 14 being blocked.

[0033] To move the head 1 to any desired position inside the pipe, especially in large pipes, the front part of the robot must be centered within the pipe. This task is performed by segment 3, to which the lifting device 2, and thus also the head 1, are mounted. Optionally, the segment also has a rotation mechanism. For this purpose, the segment must have a mechanism that allows it to expand within the pipe. In this embodiment, a double scissor lift 18 serves this purpose. Feet can be extended in one and opposite directions, which then contact the pipe wall and guide and center the segment, and thus the entire front part. The use of double scissor lifts allows for a sufficiently large change in the cross-section of segment 3, enabling the robot to be used for multiple pipe dimensions.In previously known systems, which are primarily pneumatically driven, rubber air bladders are used to expand segment 3. However, these bladders close and seal the pipe, preventing the drainage of accumulated water or other media. The double scissor strokes 18, which do not increase the entire diameter of expansion segment 3, allow the medium to continue flowing and prevent backflow. The feet, which can be pressed against the pipe wall but can also be slightly loosened when extended to facilitate forward or backward sliding of the front section, should exhibit optimal sliding properties in combination with the pipe wall in the case of the front expansion segment 3. They could, for example, be made of metal or plastic.

[0034] All segments of the robot are connected via connecting pieces 4, such as stiffened and, above all, torsionally rigid hose sections.

[0035] The remaining segments 5 are very similar to the front segment 3, also featuring mechanisms for expansion and locking within the tube. However, their feet should have the highest possible adhesive properties, for example, by using rubber feet, as these segments 5 are necessary for the robot to stay in the tube and move independently back and forth. Furthermore, these segments 5 do not necessarily need to have rotational capabilities. In the Fig. 1 and 2In the illustrated embodiments, however, they feature rotations so that the robot can align itself vertically by alternately extending and retracting the feet of the various segments 5 in combination with the rotations and, if necessary, a gyroscope sensor for position detection. When using two double scissor strokes 18, it is advantageous if the segment 5 or 3 is oriented so that the scissor strokes extend upwards and downwards, since otherwise lateral forces occur due to shearing at the pipe wall, which can be detrimental to the mechanics of the double scissor strokes 18, and the extension force of the double scissor strokes 18 decreases if they are tilted in the pipe.

[0036] As in Fig. 1 and 2As shown, it can be advantageous to deliberately rotate one of the two foremost segments 3 or 5 by, for example, 90 degrees, thus orienting it horizontally, as this can increase the stability of the front section. In particular, it reduces the lateral wobble of the front section, especially during milling or brushing with a suitable tool on the head 1. For this purpose, it makes sense to couple these two foremost segments 3 or 5 one behind the other, without the feed segment 6 in between, so that the stabilizing effect is maximized.

[0037] The feed segments 6, in combination with the expansion segments 3 and 5 respectively, enable a stepwise, worm-like drive as in Fig. 6 The feed mechanism for increasing or decreasing the distance between the two expansion segments 5 coupled to the feed 6 is implemented in this embodiment such that a sealed piston, on which one end of a connecting piece 4 is mounted, can be moved back and forth by a spindle drive.

[0038] Connector segment 7 is the rearmost part of the robot, where the main connector of the power supply cable, preferably a sliding cable, is attached. In this version, connector segment 7 also includes an emergency power supply with electronics for monitoring the main power supply. Due to the use of partially self-locking gears and the robot's clamping within the pipe, the device could not be removed from the pipe in the event of a line break or a power supply unit failure without exposing the pipe or damaging the device. Therefore, the emergency power supply is designed to store sufficient energy to retract the self-locking expansion mechanisms of expansion segments 3 and 5, as well as the self-locking feed mechanisms of feed segment 6, and, if necessary, to unlock the lifting device 2.This makes the robot as compact and flexible as possible, allowing it to be removed from the pipe. For example, the emergency power supply can consist of capacitors that can withstand many charging cycles and have a significantly shorter charging time compared to conventional batteries.

[0039] Fig. 1 Figure 1 shows the robot comprising several extension segments 3 and 5, a feed segment 6, and another segment 7, which are coupled by connecting pieces 4. In this embodiment, stiffened hoses are used as connecting pieces 4. The front part of the robot consists of an extension segment 3 for radial clamping in the tube, a lifting device 2, and the head 1 attached thereto. In this embodiment, the head 1 includes an image sensor with a corresponding lens, a light source, a wiper for cleaning dirt from the protective glass in front of the lens, and a milling motor with a milling tool.

[0040] Fig. 2 shows an extended embodiment compared to Fig. 1 , comprising a further extension segment 5 and a further feed segment 8, which can smooth the stepwise movement resulting from the interaction of at least two extension segments 3 or 5 and at least one feed segment 6, so that the front part of the robot, in particular the head 1, can be moved smoothly and continuously back and forth.

[0041] Fig. 3 Figure 1 shows an exploded view of the mechanism of the hub 2. The hub 2 comprises a rigid part, to which a bearing insert 15 is connected, and a movable part, to which a bearing insert 12 is connected. These parts are optionally supported and clamped relative to each other by an axial bearing 13 to increase the stability of the entire assembly. A worm gear 16 is mounted on one end of the hollow shaft 14, which extends from the rigid part into the movable part, and a ratchet gear 11 is mounted on the other end. In this embodiment, the shafts are secured with nuts 10. A device 9, in conjunction with the ratchet gear 11, forms a locking mechanism ( Fig. 4 ) to mechanically couple or decouple the moving part to which the bearing insert 12 is connected with the shaft 14 radially. The hollow shaft 14 is driven by a drive unit 17 with a worm on the side of the worm wheel 16 and when the hollow shaft 14 and the moving part of the stroke are engaged by the locking mechanism ( Fig. 4 Since the radially locked parts are engaged, the movable part of the stroke can be selectively moved and positioned relative to the rigid part by controlling the drive unit 17. The hollow shaft 14 allows cables or media-carrying lines to be routed through the entire stroke 2.

[0042] Fig. 4 Figure 9 shows the mechanism for locking or unlocking the movable part of the stroke 2 and the hollow shaft 14, comprising a motor 9a, a potentiometer 9e, and a threaded spindle 9c, which are coupled via a transmission, in this embodiment consisting of gears 9b. A detent element 9d, which can engage positively with the detent wheel 11, is linearly displaced along the axis of the threaded spindle 9c by its rotation, as indicated by arrows 9f. The potentiometer 9e serves to position the detent element 9d; however, the motor 9a can also be equipped with an encoder, or the position of the detent element can be defined by contact force or time.

[0043] Fig. 5 Figure 18 shows the mechanism for extending segments 3 and 5. The spindle 18d is rotatably mounted in segment 3 or 5 by the bearings 18b and can be driven via the gear 18a. In this illustration, the remainder of segment 3 or 5 is hidden, and the scissor arms are mounted on block 18c, which would otherwise be part of the segment housing but is hidden for clarity. Block 18c and the two bearings 18b are fixed in their positions. Driven by the spindle 18d, the nut 18e moves along the axis of the spindle 18d. The two mounting parts 18f of the segment feet are connected to the movable nut 18e and the fixed block 18c by double scissor arms. By rotating the gear 18a in the direction of 18g, the nut 18e is moved in the direction of 18i; this movement is redirected by the double scissor strokes and the mounting parts 18f of the segment feet move in the direction of 18k.Conversely, when the gear 18a and the associated spindle 18d are rotated in the direction of 18h, the nut 18e is moved in the direction of 18j and the mounting parts 18f are moved in the direction of 18i by the double scissor strokes. Rotation in the direction of 18g thus causes segment 3 or 5, or the segment feet, to expand, and rotation in the direction of 18h causes contraction.

[0044] Fig. 6 shows a complete step of worm-like locomotion 19 in the direction of 19g.

[0045] At the beginning, in position 19a, both expansion segments 5 are still extended, i.e., spread out in the pipe or shaft, and the feed segment 6 is contracted.

[0046] In position 19b, the front extension segment 5, in the direction of 19g, which in this representation is the right one, is retracted and ready to be moved, as it is no longer spread apart.

[0047] In position 19c, the feed segment 6 is axially extended and, in the process of extension, has also displaced the front, contracted extension segment 5.

[0048] In position 19d, both expansion segments 5 are again expanded and spread out in the pipe or shaft.

[0049] In position 19e, the rear extension segment 5, which is the left one in this illustration, is retracted and ready to be moved.

[0050] In position 19f, the feed segment 6 has retracted, pulling the rear, retracted extension segment 5 with it. Subsequently, the rear extension segment 5 extends again, and the robot returns to its initial state 19a, but shifted one step further towards 19g.

[0051] At any given time, at least one expansion segment 5 was extended and fixed the robot in the pipe or shaft to prevent the robot from slipping or sliding out.

Claims

1. Robot for trenchless pipeline and manhole rehabilitation with at least two expansion segments (3, 5), each with a self-locking expansion mechanism with at least one double scissor lift (18) for spreading and pressing against the pipe or manhole wall, an expansion segment (3) as the foremost segment, wherein the expansion mechanism for actuating the double scissor lift (18) has a spindle (18d), which is rotatably mounted in the expansion segment (3, 5) in a manner oriented in the direction of travel (19g) of the robot, and wherein all segments (3, 5) are coupled to one another via connecting pieces (4), with at least one feed segment (6) between two expansion segments (3, 5), characterised in that each feed segment (6) has a self-locking feed mechanism for increasing or decreasing the distance between the two expansion segments (5) coupled to the feed segment (6), wherein the feed mechanism has a piston which is mounted on the one end of a connecting piece (4) and is displaceable back and forth by a spindle drive.

2. Robot according to claim 1, characterised in that the expansion segments (3, 5) each have two double scissor lifts (18) that can be expanded in opposite directions, which can be jointly actuated via the spindle (18d).

3. Robot according to claim 1, characterised in that the connecting pieces (4) are stiffened and torsionally stiff hose pieces.

4. Robot according to claim 1, characterised in that on the expansion segment (3) forming the foremost segment, a lifting device (2) with a head (1) mounted thereon and provided with at least one tool and / or measuring device is provided, wherein the lifting device (2) is configured in particular to rotate and / or to raise and lower the head (1).

5. Robot according to claim 4, characterised in that the lifting device (2) has a drive element (17) and a locking device (9) which are connected to one another by means of a connecting shaft (14).

6. Robot according to claim 4 or 5, characterised in that two expansion segments (3) coupled to one another by a connecting piece (4) are connected to the lifting device (2).

7. Robot according to any of claims 1 to 6, characterised in that it has at least two feed segments (6, 8) located in each case between two expansion segments (3, 5).

8. Robot according to any of claims 1 to 7, characterised in that at least two of the successive expansion segments (3, 5) are rotatable relative to one another, in particular in order to rotate these expansion segments (3, 5) by 90 degrees relative to one another.

9. Robot according to claim 1, characterised in that its rearmost part is a plug segment (7) to which a main connecting plug of a supply cable, which is preferably configured in the form of a push / pull cable, can be plugged.

10. Robot according to any of claims 1 to 9, characterised in that it has an emergency power supply with electronics, which is preferably included in the plug segment (7) for temporarily supplying internal control components in the event of the supply breaking away, in order to move the double scissor lifts (18) of the self-locking expansion segments (3 and 5) and the self-locking feed mechanisms of the feed segments (6) together and, if necessary, to unlock the lifting device (2).

11. Robot according to claim 4, characterised in that the tools and / or measuring devices mounted on the head (1) contain at least one of the following: an ultrasonic measuring device for measuring the thickness of the pipe wall, a laser measuring device for 3D measurement of the pipe and deposits, a strong light source for selectively curing a resin hose, a laser for cutting away material or for engraving the pipe wall, a motor with brush or a milling head.

12. Robot according to claim 4 or 11, characterised in that an image sensor is mounted on the head (1) with a view to the tool(s) for transmitting a live image to a control unit and for positioning the robot at a specific location.

13. Robot according to any of claims 1 to 12, characterised by a programmed control for automatically approaching a defined point in the pipe or manhole system and / or for autonomously milling or grinding pipe or manhole walls in previously defined areas.