Guide device for guiding at least one line which is laid in a protective tube, and retrofit set and method for monitoring the movement of such a protective tube

Abstract

The invention relates to a guide device (20) for guiding at least one line (14) which is laid in a protective tube (16), in particular of a joint arm robot (2), comprising a guide unit (28) which has a securing element (34) for securing the protective tube (16) and a stationary support (24), wherein the securing element (34) can be moved along the support (24) in order to allow a compensating movement of the protective tube (16) and the at least one line (14) guided therein. Additionally, a sensor device (26) is provided which is designed to measure the movement of the protective tube (16) and thus detect movement data (M) of the protective tube (16). In this manner, a proper operation of the guide device (20) is monitored. In particular, the protective tube (16) is monitored for damage.

Description

[0001] Description

[0002] Guide device for guiding at least one cable inserted in a protective hose, as well as retrofit kit and method for monitoring the movement of such a protective hose

[0003] The invention relates to a guide device for guiding at least one cable located in a protective hose, as well as a retrofit kit and a method for monitoring the movement of such a protective hose.

[0004] The guide device is used in particular to guide a so-called hose package in a multi-axis articulated arm robot, especially in a multi-axis industrial robot. In the multi-axis industrial robots used today, several individual cables are usually fed to the foremost articulated arm, also known as the robot hand, to supply a tool attached to the robot hand, such as a welding tool. The cables include, for example, electrical supply cables, electrical control cables, data cables, and media guides for gases or liquids. These cables are combined in a so-called hose package and are usually loosely enclosed in a protective hose. Such a hose package is particularly suitable due to the relative movements of the articulated arms to one another and, in particular, due to the often adverse environmental conditions (high temperatures, aggressive media such as welding spatter, etc.).) is subjected to high loads. The protective hose is particularly exposed to high stress. A so-called corrugated pipe is often used as the protective hose.

[0005] To ensure reliable guidance of the hose assembly, a guide device with a return mechanism is typically used. This mechanism is designed to allow a compensating movement of the hose assembly during a relative movement between two articulated arms. Such a guide device in an industrial robot can be found, for example, in EP 2 956 277 A1.

[0006] The high stresses on the protective hose can lead to damage, compromising its protective effect. If a damaged protective hose is not replaced or repaired in a timely manner, this can lead to failure of the cables routed within the protective hose, resulting in a breakdown and downtime. In highly automated production facilities and industrial environments, a damaged protective hose often cannot be detected in a timely manner because access for visual inspection, for example, is limited or impossible.

[0007] Based on this, the invention is based on the object of ensuring reliable operation of such a guide device and, in particular, of being able to detect a defect in a protective hose at an early stage.

[0008] The object is achieved according to the invention by a guide device having the features of claim 1, by a retrofit kit for forming such a guide device and by a method having the features of claim 17. The advantages and preferred embodiments mentioned with regard to the guide device can also be transferred analogously to the retrofit kit and to the method and vice versa.

[0009] The guide device is generally used to guide at least one cable enclosed in a protective hose, in particular a cable of a multi-axis articulated arm robot, especially a multi-axis industrial robot, to which the guide device is attached during operation. In general, the guide device is attached in the assembled state to a processing machine which has at least two machine parts that can move relative to one another. The at least one cable, preferably a plurality of cables, and the protective hose form a hose package. The cable and the protective hose are not necessarily, but preferably, part of the guide device. In the assembled state and during operation, the protective hose is mounted on the guide device and at least then forms part of the guide device.

[0010] The guide device has a guide unit extending in a longitudinal direction, which comprises a fastening element to which the protective hose is fastened during operation. Furthermore, the guide unit comprises a stationary carrier, which is preferably fixed in place on the articulated arm robot when mounted. The guide unit is in particular an independent, compact structural unit, which as such can be mounted on a machine, in particular on the articulated arm robot, for example by means of the carrier. For example, the carrier is a base plate of a housing of the guide unit. In principle, it is also possible for the carrier itself to be part of the machine. The guide unit is, for example, a known guide unit, as described, for example, in the aforementioned EP 2 956 277 A1.

[0011] During operation, the protective hose attached to the fastening element is moved along the support relative to the support. Specifically, the fastening element is mounted on the support so that it can be moved, in particular linearly, to allow for compensatory movement of the protective hose and the at least one cable guided therein during operation.

[0012] Furthermore, the guide device has a sensor device which is designed to at least indirectly measure the movement of the protective hose and thus to record movement data, in particular movement patterns, of the protective hose during operation with the protective hose installed. In general, the movement of the protective hose, in particular of the fastening element, is recorded over time, specifically within the framework of a work cycle in which a defined movement is carried out with the guide device, starting from a starting position via at least one processing position and back to the starting position. In particular, the actual movement of the protective hose and specifically the movement relative to the carrier is measured and made available for evaluation. Preferably, a movement of the protective hose relative to a reference point of the carrier is therefore measured.

[0013] In this case, the term "at least indirect measurement of the movement of the protective hose" means that the actual movement of the protective hose is measured either directly via a measurement reference on the protective hose or indirectly via a measurement reference on a separate component. The separate component is permanently connected to the protective hose during operation. A measurement reference is understood to be a reference point or reference element whose movement is measured.

[0014] The separate component is, in particular, the fastening element or a part thereof. The particular advantage is that it is a rigid component with a defined movement sequence, which makes it particularly suitable as a measurement reference and thus for measurement.

[0015] Based on the recorded movement data, in particular based on the recorded movement pattern of the protective hose and in particular of the fastening element during the work cycle, it is checked during operation whether the guide device and thus the articulated arm robot are operating correctly. During operation, the robot and thus the hose package usually carry out periodically recurring work sequences that are specified by a robot or system control system. During such a work cycle, the protective hose carries out a defined movement pattern. Specifically, during such a work cycle, a deflection takes place from an initial position to an end position and from there back to the end position. Preferably, one or more intermediate positions are assumed at which the deflection stops, for example, for a certain period of time and / or at which a processing operation (e.g.Welding, screwing, gripping, or other handling...). After processing is completed, the robot moves to another intermediate position or end position and performs another processing operation there.

[0016] The retrofit kit according to the invention comprises such a sensor device, which is designed for mounting on an (existing) guide unit. The retrofit kit therefore also allows existing systems to be easily retrofitted.

[0017] Specifically, the retrofit kit is a modular unit that can be mounted as such on the guide unit and / or the articulated-arm robot. For this purpose, the modular unit includes mounting elements for fastening. These include, in particular, screws, clamps, etc. In a preferred embodiment, the mounting elements allow tool-free fastening. These are, in particular, magnets, so that the sensor device is attached to the articulated-arm robot, and specifically to the guide unit, exclusively by magnets.

[0018] This evaluation of the movement data is preferably carried out with the aid of an evaluation unit. Such a unit is, for example, a component of the guidance device. Alternatively, it is arranged on the articulated-arm robot or part thereof. According to a further alternative, this evaluation unit is arranged remotely from the articulated-arm robot and is, for example, integrated into a system control system or is integrated into a remote data center, for example in a cloud-based solution. In general, but especially with such a remote arrangement of the evaluation unit, the sensor device and thus preferably also the retrofit kit has, in particular, a communication interface for transmitting the movement data or, if applicable, processed movement data to the evaluation unit.

[0019] This design is fundamentally based on the realization that during operation the protective hose executes a defined, predetermined movement pattern during the various movement sequences. The movement pattern is generally understood to be the temporal progression of the movement of the protective hose, i.e. its change in position over time, specifically within the framework of the aforementioned work cycle. During proper operation, a characteristic progression of the movement data (position data, speed data or acceleration data) results, specifically the movement pattern during a work cycle. By measuring the actual movement of the protective hose relative to the wearer, movement data of the protective hose is now provided, which is checked to determine whether there is a deviation from the expected movement pattern. In the event of a deviation, a malfunction is concluded - depending on the type of deviation.

[0020] Therefore, the movement pattern is preferably recorded during a work cycle and compared with a reference pattern. The reference pattern is provided, for example, by the manufacturer of the guidance device or measured and then stored during commissioning of the guidance device.

[0021] In particular, the movement pattern and the reference pattern are based on the same work cycle, which is usually specified by the robot or system controller. Therefore, a complete movement sequence is compared with an expected movement sequence with identical control.

[0022] In a preferred embodiment, a check is provided with regard to a deviation of the movement data recorded during the measurement, in particular of the recorded movement pattern, from reference data, especially from the mentioned reference pattern.

[0023] Such a comparison makes it possible to identify deviations from an expected target course and, in particular, to make statements about the proper operation of the guidance device and, in particular, of the articulated arm robot.

[0024] In particular, the recorded movement data is evaluated with regard to damage to the protective hose. Damage to the protective hose, especially a tear, typically results in a deviation from the movement pattern. For example, with a torn protective hose, the required deflection of the protective hose to enable the desired movement sequence is less than with an intact protective hose. This is therefore characteristically reflected in the movement pattern. A damaged protective hose can be easily identified by comparing the expected (maximum) deflection with the measured (maximum) deflection.

[0025] In particular, the measured deflection at the end position and / or the intermediate position in the movement pattern is compared with the expected deflection at these positions in the reference pattern.

[0026] Alternatively or in addition to the deflection, for example, the increase (speed, acceleration) in individual sections of the movement pattern, i.e. between the individual positions (initial, intermediate and final position) within the work cycle, is evaluated and considered.

[0027] Alternatively or in addition to these measured motion data (such as displacement, speed, acceleration, etc.), statistical parameters are determined and evaluated as motion data – especially when measurements of motion patterns are repeated during the same work cycle. These include, for example, minima / maxima, and / or a standard deviation / variance of the measured motion data (such as displacement, speed, acceleration, etc.).

[0028] In a preferred embodiment, several different types of motion data and characteristics are recorded, determined, and evaluated. Different types of motion data are understood to mean different parameters, specifically different physical parameters such as speed, acceleration, etc., or derived therefrom, particularly mathematical or statistical parameters. Specifically, the minimum / maximum deflection and / or, preferably, statistical parameters such as mean, variance, and / or even a cycle time are recorded and evaluated.

[0029] By recording / determining several characteristic parameters, the accuracy of identifying possible damage cases and / or the accuracy of distinguishing between different events or damage cases is increased.

[0030] Overall, this allows for reliable detection of damage, such as a tear in the protective hose, at an early stage and especially without visual inspection. This can be replaced or repaired in a timely manner, especially before the components inside the protective hose are damaged. Overall, this enables a simple method for monitoring the movement of a protective hose, allowing for early identification of damage to the protective hose.

[0031] In addition, measuring the movement of the protective hose and especially evaluating the movement data enables further statements to be made about the operation of the guidance device, in particular about the operation of the articulated arm robot as a whole.

[0032] In a preferred further training, movement data is evaluated additionally or alternatively with regard to a malfunction of the guide device and / or the machine.

[0033] For example, there is a risk that the hose assembly or even just the cables emerging from the protective hose could get caught on an interfering contour during the various movements, meaning that the intended movement of one of the machine parts, such as a robot hand, cannot be carried out or cannot be carried out completely. For example, ring-shaped projectors enclosing the protective hose are usually arranged on the protective hose to provide friction protection. These projectors or other parts of the protective hose can get caught on protruding (interfering) contours. If this is the case, it could indicate, for example, incorrect control and thus incorrect programming of the articulated arm robot. In a preferred embodiment, the recorded movement data is therefore also checked for such disruptions to the actual movement sequence and / or incorrect programming.

[0034] In a preferred embodiment, the movement data is used to check whether the movement pattern has been changed. This can be due, for example, to a changed programming that has altered the deflection, speed, acceleration, and / or cycle time. In such a case, if a change in the movement pattern is detected (due to a changed programming), a warning message is preferably issued.

[0035] This could be, for example, a visual warning message via light elements (LEDs) on the guide device. Preferably, it is an electronic warning message that is transmitted to a remote communication unit and / or stored locally in a memory. Such a communication unit could be, for example, a user interface, such as a customer dashboard. Alternatively, such an electronic warning message can be transmitted to mobile devices (smartphones), e.g., as push messages / SMS, etc.

[0036] According to a preferred embodiment, the warning message is transmitted, for example, from the evaluation unit to a user system or a system control of a user who operates the articulated arm robot and from whom the articulated arm robot is in particular also controlled.

[0037] Depending on the changes detected, different warning messages are issued. These range from simple notifications about a possible programming change to recommendations for action in the event of a detected crack.

[0038] To measure the movement, the sensor device in a preferred embodiment has two sensor components, one of which is arranged in a fixed position and the other of which is at least indirectly connected to the protective tube and in particular to the fastening element, so that during operation, the two sensor components exert a relative movement that corresponds in particular to the relative movement to be measured between the carrier and the protective tube. The stationary sensor component is preferably firmly connected to the carrier. Alternatively, it can also be attached to a section of the housing of the guide unit or to the articulated-arm robot.

[0039] The two sensor components are also included in the retrofit kit. The aforementioned mounting elements are designed such that one, the movable sensor component, can be mounted at least indirectly on the protective hose, while the other, the stationary sensor component can be mounted on the carrier, housing, or the articulated-arm robot. This is achieved, for example, via a magnetic attachment.

[0040] The movable sensor component is preferably firmly connected to the fastening element in the assembled state, for example, via a connecting element. Since the protective tube is fixed to the fastening element, the movable sensor component directly follows the movement of the protective tube.

[0041] As an alternative to attachment to the mounting element, the movable sensor component can also be attached to the protective hose itself, for example, via a clamp. However, attachment to the mounting element is preferred, as this is a rigid element with a defined movement pattern. The mounting element preferably performs only a linear movement.

[0042] In a preferred embodiment, one of the two sensor components is a reflector, which reflects a sensor signal to be measured. The reflector is designed to suit the sensor signal (measurement signal).

[0043] Preferably, the sensor device generally comprises a transmitter and a receiver for the sensor signal. The sensor signal is actively transmitted via the transmitter, which is received by the receiver. The received sensor signal is then suitably evaluated, for example, with regard to its propagation time, in order to evaluate the desired movement data, such as position change, speed, acceleration, etc.

[0044] Depending on the design, the transmitter and receiver are arranged in a common unit or at least at the same (initial) position. In this design variant, the aforementioned reflector is additionally provided to reflect the sensor signal back to the initial position.

[0045] Alternatively, the sensor and receiver are positioned remotely from each other, with one sensor component being stationary and the other movable. In this design variant, a reflector is not required.

[0046] In a preferred embodiment, the two sensor components, i.e., the stationary and the movable sensor components, are housed in a sensor housing. They are preferably completely or at least partially accommodated in the sensor housing. This measure protects the sensor device as a whole and protects it from environmental influences. At the same time, false reflections from objects in the detection area are avoided—for example, in the case of non-targeted sensor signals. This ensures reliable and accurate measurement overall.

[0047] This sensor housing is preferably also part of the retrofit kit. This kit therefore comprises the sensor housing, on the one hand with the stationary sensor component arranged therein and, on the other hand, with the movable sensor component arranged therein. The movable sensor component is therefore also arranged to be movable with respect to the sensor housing. For this purpose, the sensor housing preferably has a (linear) guide along which the movable sensor component can be moved within the sensor housing. This guide can be, for example, a guide slot in a side wall of the sensor housing, a separate guide element within the sensor housing and / or side walls of the sensor housing. In a preferred embodiment, the one movable sensor component is connected to the protective hose via a connecting element which protrudes from the sensor housing, at least indirectly via the fastening element.This connecting element is, for example, a previously described mounting element of the retrofit kit or is connected to such a mounting element.

[0048] The sensor housing is preferably a standalone housing, which, when installed, is mounted laterally next to the guide unit. The sensor housing is preferably attached to the carrier via appropriate mounting elements, which are particularly part of the retrofit kit.

[0049] As an alternative to arranging the sensor device or at least the sensor components within a separate sensor housing, the sensor components are arranged on and in particular within the guide unit. In this case, the guide unit itself preferably comprises the aforementioned housing with an interior space in which the sensor components are arranged and thus protected from the environment.

[0050] In principle, different measuring principles are possible for detecting the movement, especially the relative movement between the carrier and the protective hose.

[0051] According to an advantageous embodiment, the sensor device is designed for ultrasonic measurement, and one sensor component is an ultrasonic transmitter. Another sensor component is an ultrasonic receiver. Preferably, the movable sensor component is a reflector for the ultrasonic signal (sensor signal).

[0052] Alternatively, the sensor device is designed for optical measurement, with one sensor component being an optical transmitter and another sensor component being an optical receiver. Specifically, these are semiconductor components, in particular an LED as the transmitter and a photodiode as the receiver. Here, too, a reflector is provided as the movable sensor component in a preferred embodiment.

[0053] According to a further preferred variant, the sensor device is designed for an electrical or electromagnetic measurement and in particular for a capacitive or inductive measurement. In principle, different configurations are possible here. For a capacitive or inductive measurement, one or more electrical components, such as electrodes, electromagnetic coils, (permanent) magnets, etc., are arranged distributed along the displacement path of the protective tube / fastening element, for example on the carrier or on another stationary component of the guide unit, for example on a housing cover forming a housing cover. Complementary to this, a second electrical or electromagnetic component, such as an electrode, an electromagnetic coil, or a (permanent) magnet, is arranged on the protective tube and specifically on the fastening element.The elements arranged along the displacement path, for example, each lead to a counting pulse, and the movement can be inferred from the counting pulses. As an alternative to the arrangement of discrete, individual electrical / electromagnetic components, a continuous component with a changing characteristic can also be arranged along the displacement path. For example, a continuous electrode is formed whose width changes continuously. So that when a counter electrode arranged on the fastening element, for example, is moved, a capacitance measured between the two electrodes changes continuously. Based on the capacitance value recorded in each case, a defined position and thus a movement over time can be inferred.

[0054] According to a preferred embodiment, the sensor device has a mechanical auxiliary element, in particular a cable, which is at least indirectly connected to the protective hose and, for example, to the fastening element and is movable together with them. In a preferred embodiment, the cable is attached to the protective hose via a clamp. The sensor device is further designed to measure the movement of the mechanical auxiliary element. A cable is generally understood to be a flexible, strand-like element. This can be a cable in the narrower sense, a band, a chain, a belt, etc. The cable can also be guided over a deflection pulley or wound up via a winding mechanism. In particular, a cable sensor is used, which detects the mechanical movement of the cable. For example, the winding and unwinding movement of a winding mechanism is evaluated.

[0055] As an alternative to a rope, a rigid mechanical element such as a rod can be provided which moves together with the protective hose or the fastening element and whose movement is detected.

[0056] The guide unit generally has a return mechanism designed for automatic, particularly spring-actuated, retraction of the protective hose to an initial position. The spring-actuated return mechanism exerts a preload on the protective hose, specifically via the fastening element. Deflection of the hose assembly from its initial position occurs through a forced movement of the processing machine, specifically the articulated-arm robot, for example, through a forced movement of the robot hand to which the at least one cable is attached.

[0057] This retrieval mechanism is particularly attached to the carrier.

[0058] The fastening element further comprises a sliding element, onto which the return mechanism exerts the return force. The sliding element is, in particular, a carriage that is guided along a guide, in particular a linear guide.

[0059] The reset mechanism is housed, in particular, in the housing of the guide unit. This housing has at least one slot and preferably two opposite lateral longitudinal slots. The internal slide element is connected to a fastening clamp for securing the protective hose through the at least one slot. The slide element and fastening clamp form the fastening element or are at least part of the fastening element. Preferably, the fastening element generally has such a fastening clamp for clamping the protective hose.

[0060] The fastening element has in particular a bracket which surrounds the housing cover and whose edge-side bracket arms engage into the interior of the housing via the two mentioned lateral longitudinal slots and are connected there to the return mechanism, specifically to the slide element.

[0061] The previously mentioned movable sensor component is preferably firmly connected to this bracket.

[0062] In a preferred embodiment, the guide device comprises at least one sensor element and preferably several sensor elements, as well as an evaluation unit. The sensor elements are designed to acquire sensor data that correlates with the condition of the protective hose, thus allowing statements to be made about the current condition of the protective hose.

[0063] The sensor data preferably comprises, at least in part, the movement data of the protective hose. The sensor elements therefore comprise, at least in part, the sensor components described above.

[0064] Alternatively, and in particular in addition, additional sensor data, such as temperature data and / or humidity data, are used. These data are recorded via suitable (additional) sensor elements, such as temperature sensors, humidity sensors, etc. The temperature is, in particular, the ambient temperature and / or the temperature of the protective hose. The evaluation unit, in conjunction with the sensor elements, is configured to repeatedly record the sensor data during operation and to evaluate it with regard to the current wear status of the protective hose. If this evaluation indicates a critical wear status, a warning message is issued or at least stored in a memory.

[0065] Repeated acquisition means that the data is regularly recorded at specific times, for example, periodically after a certain period of time, during operation in order to obtain information about the current state of wear. The periodic acquisition of the sensor data is, for example, in the range of seconds or even milliseconds, in particular in the range of 10 to 20 milliseconds. The periodic evaluation of the sensor data is, for example, in the range of minutes, preferably from 1 to 20 minutes, in particular from 1 to 10 minutes, especially from 1 to 3 minutes.

[0066] This measure enables continuous monitoring of the wear condition of the protective hose. Overall, it creates an early warning system. This measure has the particular advantage of allowing early detection of critical wear conditions, allowing for timely repair or replacement. This prevents damage and / or downtime due to protective hose failure.

[0067] In a preferred embodiment, one or both of the following steps are performed during the evaluation: a) The sensor data is processed using a filter algorithm so that noise components, interference signals, and / or irrelevant signal components, which are particularly irrelevant for assessing the wear condition of the protective hose, are filtered out, and filtered sensor data is obtained. b) Predefined characteristic values ​​are extracted from the sensor data, in particular from the filtered sensor data, using an extraction algorithm.

[0068] Based on these extracted parameters, the current wear condition of the protective hose is preferably derived.

[0069] These steps allow for a precise assessment of the current wear condition of the protective hose, reliably and, in particular, with minimal computational effort.

[0070] The specified characteristic values ​​can in particular be one or both of the following characteristic values: a) From the temporal course of the sensor data, a minimum or a maximum of the course is used as the characteristic value, b) The sensor data are subjected to a statistical evaluation and a statistical characteristic value is used as the characteristic value, in particular the variance or standard deviation of a measurement parameter, whereby the values ​​of the measurement parameter are provided by the sensor data.

[0071] Preferably, additional characteristic values ​​can be recorded, extracted, and evaluated within the scope of the method. Preferably, up to 15, in particular up to 35, and especially up to 50 characteristic values ​​can be recorded, extracted, and evaluated.

[0072] In a preferred development, the evaluated sensor data is compared with reference data, and the wear status is determined based on the comparison. This enables simple and rapid evaluation.

[0073] In a preferred embodiment, the reference data is determined from sensor data obtained during a learning phase after installation of the guidance device. The learning phase lasts, for example, one or more years (e.g., 1-3 years), preferably several months (e.g., a period of 1 to 6 months), or even weeks (e.g., a period of 1 to 4 weeks), or even days (e.g., a period of 1 to 14 days).

[0074] The wear evaluation takes place during a monitoring phase following the learning phase. The monitoring phase can also serve as a learning phase during ongoing operation of the guide device, allowing interference factors that occur during long-term operation to be filtered out, thereby increasing detection and monitoring accuracy.

[0075] To evaluate the sensor data with regard to wear status, a self-learning algorithm, specifically based on AI (artificial intelligence), is preferably used. This applies particularly to the learning phase and / or the monitoring phase.

[0076] The evaluation of the sensor data is carried out, for example, locally on site with an evaluation unit that is part of the guidance device and / or part of a control system of the articulated arm robot to which the guidance device is attached.

[0077] Alternatively, the evaluation takes place at a remote location, particularly within a cloud system. This means, in particular, that a communication interface is implemented through which the sensor data or values ​​derived from it are transmitted to the cloud system, particularly via the Internet, where they are evaluated in a suitable manner. This cloud system could, for example, be a remotely accessible storage space provided by the manufacturer of the guidance device.

[0078] Preferably, the (additional) evaluation unit for carrying out the evaluation of the sensor data is integrated within the cloud system.

[0079] Conveniently, the reference data is taken from the sensor data of several guidance devices, which are arranged in particular at different locations, with their sensor data being jointly recorded and evaluated in the aforementioned remote storage, in particular in the cloud system. The reference data is then determined from these, for example, as values ​​averaged across several guidance devices.

[0080] Embodiments of the invention are explained in more detail below with reference to the figures, which show, in partially simplified representations:

[0081] FIG 1 shows a simplified side view of an industrial robot with a guidance device,

[0082] FIG 2 a perspective view of a guide device without a hose package with a first sensor device,

[0083] FIG 3 is a plan view of the guide device according to FIG 2, but with various additional sensor devices which are shown together in FIG 3 for illustration purposes only,

[0084] FIG 4 shows a simplified representation of a movement pattern in which the location is plotted against time, for the case of an undamaged protective tube and for the case of a damaged protective tube in comparison, and

[0085] FIG 5 shows a simplified block diagram illustrating a monitoring and early warning system.

[0086] FIG 1 shows an articulated arm robot 2 as a processing machine, in particular in one embodiment as a multi-axis, in particular six-axis, industrial robot. This generally has a base 4 and a first segment, also referred to as a rocker arm 6, which is connected to the base 4 via a first articulated connection R1. The rocker arm 6 can be pivoted about a horizontal axis about this first articulated connection R1. In addition, the rocker arm 6 can usually be pivoted about a vertical axis relative to the base 4. The rocker arm 6 extends approximately vertically upwards. At a second articulated connection R2, a second segment, generally referred to as the robot arm 8, is connected to the rocker arm 6 so as to be pivotable about a so-called "axis 3". Furthermore, a robot hand 10, as a third segment, is connected to the robot arm 8 via a third articulated connection R3.Finally, a processing tool 12, such as a welding gun, etc., is attached to the robot hand 10. Such an industrial robot typically has more than four or more than five, and for example, six different degrees of freedom of movement.

[0087] To supply the processing tool 12 with electricity and / or fluids and / or data signals, the articulated-arm robot 2 has a supply line package that runs along the robot arm 2 and is connected from there, for example, to the base 4. The supply line package has at least one line 14 and preferably a plurality of lines 14 that are guided in a protective hose 16 at least in the region of the robot arm 8. The lines 14 together with the protective hose 16 are also referred to below as the hose package 18. A separation point for the supply line package is often arranged in the region of the second articulated connection R2, and the hose package 18 is guided as a replaceable wear unit up to this separation point.

[0088] During operation, for example, during a rotational movement around the third joint axis R3, a relative movement occurs between the various segments of the articulated-arm robot 2, and a pulling movement is exerted on the hose assembly 18. During the reverse movement back to its starting position, the hose assembly 18 must be retracted again.

[0089] To guide the hose assembly and, in particular, to perform this return movement, a guide device 20 is mounted in the area of ​​the second articulated connection R2 on the robot arm 2. This guide device 20 includes a fastening clamp 22 in which the hose assembly 18 is held, in particular in a form-fitting manner, so that a restoring force exerted by the guide device 20 is transferred to the hose assembly 18.

[0090] The guide device 20 has a support 24, with which it is attached to the articulated-arm robot 2, in particular in the area of ​​the second joint R2. When the hose package 18 moves, the hose package and, with it, the fastening clamp 22, perform a particularly linear movement relative to the support 24. A return mechanism 25 is mounted on the support, which exerts an elastic return force on the fastening clamp 22. For this purpose, the fastening clamp 22 is connected in particular to a slide element (not shown in detail), which is attached to the support 24 for linear movement.

[0091] The protective hose 16 is often a so-called corrugated pipe, in which the multiple lines 14 are typically loosely guided. The hose assembly 18, and in particular the protective hose 16, are wear parts. If damage, such as a tear in the protective hose 16, is not detected early, this may lead to damage to the internal lines 14 and can cause an unintentional failure of the entire articulated-arm robot 2 and thus, for example, an entire assembly line within an industrial manufacturing process.

[0092] For early detection of damage to the protective hose 16, the guide device 20 is now equipped with a sensor device 26, as will be explained in more detail below with reference to Figures 2 to 4.

[0093] The illustrated guide device 20 initially comprises a guide unit 28. This comprises a housing 30, which has the support 24 on the bottom, to which a housing cover 32 is attached. In the free interior space, a return mechanism (not shown in detail here) is formed, which has an elastic return element, in particular a spring element, which exerts an elastic return force on a slide element (not shown). The guide unit 28 has a fastening element 34 connected to the slide element, which is linearly displaceable along the support 24. In the exemplary embodiment, this fastening element 34 comprises a bracket 36, which encompasses the housing cover 32 and engages into the interior space via lateral longitudinal slots, where it is connected to the slide element. The previously mentioned fastening clamp 22, in which the protective hose 16 is fixed when installed, is attached to the bracket 36.In the printout example, the guide unit 28 has a sliding guide at its front end, which is fixedly connected to the carrier 24 and through which the hose package 18 is guided in a sliding manner.

[0094] During operation, the protective hose 16 and with it the fastening clamp 22 as well as the entire fastening element 34 are therefore moved linearly back and forth along the guide unit 28 to enable the compensating movement. The articulated arm robot 2 is usually programmed for periodically recurring work sequences, for example, to perform several individual welding operations on a component within a work cycle. The same work cycle is repeated for the next component. Within such a work cycle, the protective hose 16 and thus the fastening element 34 perform a defined movement pattern. Based on the movement pattern, it can be determined whether the guide device 20 and / or the articulated arm robot 20 are executing a correct movement sequence according to a target specification.

[0095] The sensor device 26 measures the movement sequence of the hose package 18, in particular the relative movement of the protective hose 16 relative to the carrier 24, and evaluates the movement data recorded in the process.

[0096] There are basically several options available for this, which are explained in more detail below in connection with Figure 2 or Figure 3.

[0097] What all variants have in common is that the (linear) movement of the fastening element 34, in particular of the bracket 36, relative to the support 24 is detected and evaluated. Thus, the actual movement of the fastening element 34 and, with it, the actual movement of the protective tube 16 are measured directly.

[0098] For this purpose, the sensor device 26 comprises a first movable sensor component 38A and a second, stationary sensor component 38B. The movable sensor component 38A is attached to the fastening element 34, whereas the stationary sensor component 38B is attached to the carrier 24. The sensor device 26 measures the relative movement of the movable sensor component 38A relative to the stationary sensor component 38B.

[0099] In several of the embodiments described below, the movable sensor component 38A is designed as a reflector, and the stationary sensor component has a transmitter and, preferably, also a receiver. A suitable sensor signal S is emitted via the transmitter, which is reflected by the reflector and returned to the stationary sensor component 38B, where it is detected by the receiver. The current position of the movable sensor component 38A is evaluated, for example, by evaluating the propagation time of the sensor signal S. This basic principle is generally explained in connection with Figure 2. The sensor signal S is preferably an ultrasonic signal. Alternatively, an optical signal is used.

[0100] Figure 3, which shows a top view of the guide device 20, shows several different variants of the sensor device 26 in parallel and side by side. Typically, only one of these variants is used.

[0101] According to a first preferred embodiment, the sensor device 26 comprises a sensor housing 40, which is arranged next to the guide unit 28 and, in particular, is fastened thereto. The two sensor components 38A, 38B are arranged within the sensor housing 40. The sensor housing 40, and in particular the entire sensor device 26, is fastened to the guide unit 28 via mounting elements 42. Alternatively, fastening to a component of the articulated-arm robot 2, such as the robot arm 8, is also possible.

[0102] The sensor housing 40 is preferably designed as an at least largely closed housing so that the components contained therein are protected from the environment. The sensor housing 40 is provided, for example, with a reversibly closable opening for inspection purposes. It should be emphasized that the movable sensor component 38 arranged in the sensor housing 40 is connected to the fastening element 34 and specifically to the bracket 36 via a connecting element 43 protruding from the sensor housing 40. The connecting element 43 therefore exerts a relative movement to the sensor housing 40 during operation. For this purpose, the sensor housing 40 preferably has a longitudinal slot on a side wall along which the connecting element 43 can move.

[0103] The use of the sensor housing 40 is particularly advantageous, particularly in the embodiment variant in which an ultrasonic signal is used as the sensor signal S, since unwanted (false) reflections caused by the contours of the guide unit 28 and / or the articulated-arm robot 2 or other components in the surrounding area are avoided. Even with an optical sensor signal S, a closed sensor housing 40 creates defined measurement conditions, ensuring reliable detection and measurement of the movement.

[0104] The central image area of ​​Figure 3 illustrates a sensor device 26 with an electrical detection principle based on capacitive measurement. In this embodiment, a stationary electrode 44 is formed, to which a movable counterelectrode (not shown in detail here) is assigned, which is connected in particular to the fastening element 34. In the exemplary embodiment, the electrode 44 is formed on the upper side of the housing cover 32. The counterelectrode is formed, for example, on an underside of the bracket 36. In the exemplary embodiment, it is further provided that the electrode 44 continuously changes its geometry in the longitudinal direction of the guide unit 28 and thus in the displacement direction of the fastening element 34. Specifically, in the exemplary embodiment, it is designed as a continuously tapered electrode 44.This results in a defined capacitance being formed depending on the current position of the fastening element 34, which thus varies with the position. This capacitance is measured in a suitable manner, and the current position is thus determined. As an alternative to the continuous electrode 44 shown, individual discrete electrodes can also be arranged. An inductive measuring principle is used as an alternative to a capacitive measuring principle.

[0105] Finally, the upper section of Figure 3 shows a further embodiment variant with a mechanical measuring principle: in this embodiment variant, a mechanical aid, in particular a cable 46, is connected to the fastening element 34. A stationary cable unit 48 is connected to the carrier 24. This has, in particular, an integrated cable sensor (not shown in detail here), which detects the varying deflection of the cable 46 and thus the relative movement of the fastening element 34. For this purpose, a winding mechanism for the cable 46, which is, for example, spring-loaded, is integrated within the cable unit 48.

[0106] The movement data acquired by the sensor device 26 are transmitted to an evaluation unit 48. This is preferably part of the sensor device 26 attached to the guide unit 28. It is preferably arranged on or in the sensor housing 40, as sketched in Figure 3. Generally, it is, for example, fixedly attached to the guide unit 28, at least indirectly.

[0107] The evaluation of the movement data, as explained in more detail below, particularly in connection with Figure 4, is alternatively carried out in a remote evaluation unit, which is, for example, integrated into a system control system of the articulated-arm robot 2, or is part of a cloud-based solution. Such a remote evaluation unit is also part of the sensor device 26, which in this case has several structural units or functional units that are arranged in a distributed manner. In such a case, the part of the sensor device 26 attached to the guide unit 28 is designed at least to emit a suitable communication signal for transmitting the possibly processed measurement data to the remote evaluation unit.

[0108] Figure 4 shows an example of a deflection x versus time t of the protective hose 16. During a work cycle, the protective hose 16 and with it the fastening element 34 perform a predefined movement pattern. Starting from an initial position at time t0, a deflection occurs up to a first intermediate position x1 at a time t1. Here, for example, a first machining operation (welding) takes place, which takes a certain time. After completion of this machining operation at time t2, a further deflection occurs up to a further intermediate position x2 with, for example, a maximum deflection, at which a further machining operation takes place. Starting from this, the hose assembly 18 is returned to the original starting position x0 via a further machining operation at an intermediate position x3, but at the end of the work cycle (cycle time T).

[0109] The upper curve defines a target or reference pattern, which is formed by reference data R (a multitude of individual location-time pairs (xi, tj)).

[0110] During proper operation, a measured movement pattern, which is formed from measured movement data B, corresponds to the reference pattern – within permissible tolerances. However, in the event of disturbances, the measured movement pattern deviates from the reference pattern, whereby the type of disturbance can and will be deduced from the deviations. This occurs within the evaluation unit 48.

[0111] This is explained using the example of a crack in the protective tube 16: With such a crack, the actual deflection of the protective tube 16 is usually less than the expected target deflection. This results in the corresponding intermediate positions assuming a lower position value than the target values. In this case, the measured movement pattern is therefore shifted downwards, for example, in the negative x-direction.

[0112] Depending on the application and the type of damage, a crack can also lead to a larger deflection or to a similar deflection, but with different other movement characteristics. Against this background, a large number of different parameters are determined, including derived parameters, such as a variance, particularly in the deflection. This ensures reliable and accurate evaluation and determination of the current movement situation.

[0113] In principle, other malfunctions or errors can also be detected based on the evaluation of the movement pattern and can be evaluated accordingly. If such a malfunction is identified by the evaluation unit 28, a warning signal is issued.

[0114] With the guide device 20 described here with the sensor device 26 arranged thereon, damage to a protective hose 16 and / or any other fault can be detected at an early stage and suitable countermeasures can be taken, such as, for example, issuing a maintenance message.

[0115] The sensor device 26 is designed, in particular, for retrofitting to existing guide units 28. For this purpose, a retrofit kit 50 is provided, which can be subsequently mounted to an existing guide unit 28. This retrofit kit 50 comprises, in particular, the two sensor components 38A, 38B, preferably the evaluation unit 48 and / or at least one communication unit for transmitting data signals to a remote evaluation unit. Furthermore, the mounting elements 42 preferably belong to the retrofit kit 50. In the embodiment with the sensor housing 40, this is part of the retrofit kit. Preferably, the retrofit kit 50 has a common mounting unit formed from these elements or is such an assembly unit. This consists, in particular, of the sensor housing 40 and the mounting elements 42, wherein the sensor components 38A, 38B are already contained pre-assembled within the sensor housing 40.In one variant, the evaluation unit 48 is also part of this assembly unit. In this case, only assembly on the guide unit 28 is required. In conjunction with FIG. 5, a monitoring and early warning system is described below, which serves to continuously and regularly check the condition of the protective hose 16.

[0116] The protective hose 16 in such guide devices 20 is regularly subject to wear during operation. The frequently high stresses can also lead to damage to the protective hose 16. Both wear and damage impair the protective effect of the protective hose 16. If such a damaged or worn protective hose is not replaced in a timely manner, this can lead to failure of the lines 14 guided in the protective hose, and this can result in a failure and shutdown of the system. Especially in automated production systems in which articulated arm robots 2 with such guide devices 20 are used, especially in industrial environments, accessibility is often not available or only limited for safety reasons, for example for a visual inspection.

[0117] And now to enable a control of the wear condition of the protective hose 16, the monitoring system or early warning system according to FIG 5 is provided:

[0118] This has at least one sensor element 60 and in particular a plurality of, even different, sensor elements 60, which, during operation of the guide device 20, acquire sensor data D and transmit it to an evaluation unit 48. In the exemplary embodiment of FIG. 5, this is, for example, the previously described evaluation unit 48 of the guide device 20. Alternatively, an additional evaluation unit can be part of the guide device 20.

[0119] In the preferred alternative, an evaluation unit 48' is arranged remotely from the guide device 20 and, in particular, also remotely from the articulated-arm robot 2. In this case, the individual sensor data D are transmitted, possibly already processed, to this remote evaluation unit 48'. This is, for example, part of a cloud system 62. In general, the sensor data D are evaluated in the evaluation unit 48, 48' with regard to the current wear state, as explained in the general description section.

[0120] The sensor data D are at least partially or exclusively sensor data D of the previously described sensor device 26, i.e. specifically the movement data M of the protective hose 16.

[0121] Preferably, additional, different sensor data D are also recorded and taken into account for the evaluation. This includes, for example, temperature data of either the environment and / or the protective hose 16.

[0122] For the evaluation, the sensor data D or variables derived therefrom are preferably compared with reference data, in particular the previously described reference data R.

[0123] The acquisition of the sensor data D and their evaluation takes place continuously during the operation of the guide device 20, in particular at periodically recurring time intervals.

[0124] The reference data R are stored, for example, in the evaluation unit 48, 48'.

[0125] The reference data R are preferably derived from the recorded sensor data D during a learning phase. The learning phase is in particular a defined period of time, for example several days, several weeks or several years after commissioning of a (new) guide hose 16. A learning phase is preferably carried out again each time the guide hose 16 is replaced. In this way, the sensor data D are recorded for the new state or for a certain period from the start of operation and later - i.e. during a monitoring phase following the learning phase - used as reference data R. The directly determined sensor data D (raw data) or data derived from this or data determined during further operation can be used as reference data.

[0126] Alternatively or additionally, the sensor data D from various guidance devices 20 are recorded in the remote evaluation unit 48' in order to obtain the broadest possible database. General reference data R, for example, is then derived from this sensor data D.

[0127] When comparing with the reference data, one variant checks whether a limit value (minimum / maximum) has been exceeded.

[0128] Alternatively, an evaluation algorithm is used, for example, using machine learning specifically using AI (artificial intelligence) and taking previous (historical) sensor data into account, to learn an OK state as reference data. This allows a failure of the protective device to be detected with high accuracy.

[0129] Upon detection of a failure of the protective hose 16, a warning message is issued, and the responsible persons, for example, are immediately informed. The warning is preferably transmitted automatically, for example, via common communication channels such as email, SMS, etc.

[0130] Automatic detection and notification make it possible to repair the protective hose promptly and prevent damage to the internal wiring. Preferably, the warning already contains information relevant to the repair or replacement of the protective hose 16, such as part numbers. This can reduce maintenance time.

[0131] In a preferred embodiment, a status image of the respective system (e.g., guidance device 20 or entire articulated-arm robot 20) is created and preferably also displayed graphically, for example, as a dashboard, so that the current status of the entire system can be seen.

[0132] 2 articulated arm robots

[0133] 4 Base

[0134] 6 swingarm

[0135] 8 Robot arm

[0136] 10 robot hand

[0137] 12 Editing tool

[0138] 14 Line

[0139] 16 Protective hose

[0140] 18 hose package

[0141] 20 Guide device

[0142] 22 Mounting clamp

[0143] 24 carriers

[0144] 25 Reset mechanism

[0145] 26 Sensor device

[0146] 28 management unit

[0147] 30 housings

[0148] 32 Housing cover

[0149] 34 Fastening element

[0150] 36 brackets

[0151] 38A movable sensor component

[0152] 38B stationary sensor component

[0153] 40 sensor housings

[0154] 42 Mounting element

[0155] 43 Connecting element

[0156] 44 Electrode

[0157] 46 rope

[0158] 48 Evaluation unit

[0159] 50 retrofit kit

[0160] 60 sensor elements

[0161] R1 1 . Articulated connection

[0162] R2 2. Articulated connection

[0163] R3 3. Joint connection

[0164] S Sensor signal R Reference data

[0165] M measured movement data

[0166] D Sensor data

Claims

Claims 1. A guide device (20) for guiding at least one line (14) located in a protective hose (16), in particular of an articulated arm robot (2), having a guide unit (28), wherein the guide unit (28) has a stationary support (24) and a fastening element (34) for fastening the protective hose (16), wherein the fastening element (34) is movable along the support (24) in order to enable a compensating movement of the protective hose (16) and of the at least one line (14) guided therein, characterized in that the guide device (20) comprises a sensor device (26) which, during operation with the protective hose (16) mounted, is designed to at least indirectly measure the movement of the protective hose (16) and thereby to record movement data (M) of the protective hose (16).

2. Guide device (20) according to the preceding claim, characterized in that the guide device (20) has an evaluation unit (48) which is designed to evaluate the movement data (M) recorded during the measurement with regard to a deviation from reference data (R).

3. Guide device (20) according to the preceding claim, characterized in that the evaluation unit (48) is designed such that the recorded movement data (M) are evaluated with regard to a disturbance in the movement sequence of the guide unit (28) and / or a change in a movement pattern of the guide unit (28).

4. Guide device (20) according to the preceding claim, characterized in that the evaluation unit (48) is designed such that the movement pattern of the guide unit (28) is detected during a working cycle and compared with a reference pattern, wherein within the scope of the working cycle the guide unit (28) and thus the protective hose (16) executes a defined movement pattern and in particular from a Starting position via preferably at least one intermediate position at which a machining operation takes place, to an end position and from there back to the starting position.

5. Guide device (20) according to the preceding claim, characterized in that the reference pattern and the movement pattern are based on the same, in particular periodically recurring, working cycle.

6. Guide device (20) according to one of claims 2 to 5, characterized in that the evaluation unit (48) is designed such that the recorded movement data (M) are evaluated with regard to damage to the protective hose (16), in particular with regard to the occurrence of cracks.

7. Guide device (20) according to the preceding claim and according to claim 4 or 5, characterized in that the evaluation unit (48) is designed such that on the basis of a comparison of the deflection at an intermediate or end position in the reference pattern and in the measured movement pattern, a conclusion is drawn as to damage to the protective hose (16).

8. Guide device (20) according to one of the preceding claims, characterized in that the sensor device (26) has two sensor components (38A, 38B) for measuring the movement, one sensor component (38A) is at least indirectly connected to the protective hose (16) and the other sensor component (38B) is arranged in a stationary manner, so that the two sensor components (38A, 38B) exert a relative movement during operation.

9. Guide device (20) according to the preceding claim, wherein the one sensor component (38A) is connected to the fastening element (34).

10. Guide device (20) according to one of the two preceding claims, wherein the one sensor component (38A) is a reflector for a sensor signal (S) to be measured.

11. Guide device (20) according to one of claims 8 to 10, in which the two sensor components are housed at least in sections (38A, 38B) in a sensor housing.

12. Guide device (20) according to the preceding claim, wherein the sensor housing (40) is mounted laterally next to the guide unit (28).

13. Guide device (20) according to one of the two preceding claims, in which the sensor housing (40) is attached to the carrier (24) 14. Guide device (20) according to one of the preceding claims, characterized in that the sensor device (26) is optionally - designed for an ultrasonic measurement and the one sensor component (38B) has an ultrasonic transmitter; - is designed for optical measurement and one sensor component (38B) has an optical transmitter, - is designed for an electrical or electromagnetic measurement, in particular for a capacitive measurement.

15. Guide device (20) according to one of the preceding claims, characterized in that the sensor device (26) has a mechanical auxiliary element, in particular a cable (46), which is at least indirectly connected to the protective tube (16) and in particular to the fastening element (34), and that the sensor device (26) is further designed to measure the movement of the mechanical auxiliary element.

16. Guide device (20) according to one of the preceding claims, wherein the guide unit (28) has an integrated return mechanism (25), which is designed for an automatic, in particular spring-actuated return of the protective tube (16) into a starting position, wherein the return mechanism (25) is mounted in particular on the carrier (24).

17. Guide device (20) according to the preceding claim, wherein the fastening element (34) has a bracket (36) which engages around a housing cover (32) of the guide unit (28).

18. Guide device (20) according to one of the preceding claims, characterized in that the sensor device (26) has at least one sensor element (60) for detecting sensor data (D) correlated with the state of the protective hose and an evaluation unit (48) for evaluating the sensor data (D), wherein the evaluation unit (48) is designed to repeatedly detect the sensor data during operation and to evaluate it with regard to a current state of wear of the protective hose.

19. Retrofit kit (50) for forming a guide device (20) according to one of the preceding claims, wherein the retrofit kit has a sensor device (26) which can be mounted on a guide unit (28) and which is designed to measure the movement of a protective hose (16) of the guide unit (28).

20. Method for monitoring the movement of a protective hose (16) of a guide device (20) which serves to guide at least one line (14) located in the protective hose (16), wherein the guide device (20) has a guide unit (28) with a fastening element (34) for fastening the protective hose (16) and with a stationary support (24), wherein the fastening element (34) is movable along the support (24) in order to enable a compensating movement of the protective hose (16) and of the at least one line (14) guided therein, wherein a movement of the protective tube (16) relative to the carrier (24) is measured and movement data (M) are recorded.

21. Method according to the preceding claim, wherein a movement pattern of the protective tube (16) is measured and compared with a reference pattern.

22. Method according to one of the two preceding claims, in which the protective hose (16) is checked for damage based on the measured movement data (M).

23. Method according to one of claims 19 to 23, in which sensor data (D) are repeatedly recorded with the aid of at least one sensor element (60) and evaluated with regard to a wear condition of the protective hose (16), wherein in the event of a critical wear condition a warning message is issued, wherein the sensor data (D) preferably at least partially comprises the movement data (M) of the protective hose (16).

24. Method according to the preceding claim, in which at least one or both of the following steps are carried out during the evaluation: a) the sensor data are processed using a filter algorithm so that noise components, interference signals and / or irrelevant signal components are filtered out and filtered sensor data are obtained, b) predetermined characteristic values ​​are extracted from the sensor data, in particular from the filtered sensor data, using an extraction algorithm, wherein the current state of wear is preferably derived on the basis of the extracted characteristic values.

25. Method according to the preceding claim, in which the predetermined characteristic values ​​are at least one or at least both of the following characteristic values: a) From the temporal course of the sensor data, a minimum or a maximum of the course is used as the characteristic value, b) the sensor data are subjected to a statistical evaluation and a statistical parameter is used as a characteristic value, in particular the variance or the standard deviation of the recorded sensor data.

26. Method according to one of claims 23 to 25, wherein the evaluated sensor data are compared with reference data, and the wear condition is determined based on the comparison.

27. Method according to the preceding claim, wherein the reference data are derived from the sensor data determined during operation during a learning phase after installation of the guide device, and wherein the evaluation with regard to the wear condition is further performed during a monitoring phase following the learning phase.

28. A method according to any one of the two preceding claims, wherein the reference data is derived from sensor data obtained from a plurality of guidance devices.

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