Cable drum for pipe inspection systems

Abstract

Cable drum (1) for pipe inspection systems, comprising a housing (2) with a drum core (6) mounted therein and rotatably driven, and a feed and discharge device (4) for winding a cable (5) into adjacent turns on the drum core (6), wherein the feed and discharge device (4) has a guide device (25) on which a slide unit (10) is driven to be movable in a transverse direction to the winding direction, wherein the slide unit (10) is associated with a roller guide for the cable (5), characterized in that at least two drive rollers (31, 32) forming a roller gap (39) between them for the frictional drive of the cable are arranged within the feed and discharge device (4), which extend longitudinally over the entire feed width of the cable drum (1), and that the slide unit (10) is movable along the entire length of the drive rollers (31, 32) and has at least two arms (12,44) having, which are arranged on both sides of the roller gap (39), and that at least one pair of rollers (11a, b, 41a, b) is rotatably mounted on each arm, which guides the cable (5) laterally.

Description

The subject of the invention is a cable reel for pipe inspection systems according to the preamble of claim 1.Such cable reels for pipe inspection systems are used to wind and unwind cables, such as power cables or signal cables. The power cable can be used, for example, to supply a carriage which is moved in a channel with electrical energy from an inspection vehicle which is standing on the surface of the earth. The signal cable can be used for a data transmission from and to the car.A pipe inspection system can be, for example, a carriage as shown in WO 2017 / 205783 A1, or a so-called sliding room. Usually, an image recording device (camera) is integrated in a pipe inspection system. Regardless of which pipe inspection system is brought into the channel, it draws a cable fastened thereto behind it as a current and / or signal line.The cable is wound onto a vehicle-side cable drum of the inspection vehicle or is unwound from the latter again. Because of the slackness of the cable, winding onto the cable drum is extremely cumbersome, since it can become entangled or so-called empty loops form if it is tensioned too loosely. The cable could thus be squeezed or damaged.Winding cables in the channel has proved to be particularly difficult if the cable is heavily contaminated, smeared or loaded with foreign bodies attached thereto.It is thus important in such cable reels that the cable can be wound onto a vehicle-side cable reel in a simple and reliable manner and can be unwound from the latter again without crossovers occurring in the cable in this case.DE 20 2018 105 386 U1 shows a cable drum which has a frame and a drum core, wherein the drum core is rotatably arranged on the frame and a cable can be wound onto and unwound from the drum core.On the frame, radially outside the drum core, a carriage unit with a drive device is arranged, which serves to feed the cable in windings lying next to one another on the drum core. For this purpose, the carriage unit is driven so as to be movable along a guide device in the transverse direction to the winding direction, wherein the rail-like guide device is preferably at least as long as the width of the cable receptacle.For the defined winding or unwinding, the carriage unit has a roller guide, consisting of two or more rollers, which rest on the cable jacket with a predetermined force and with which the feed of the cable for winding or unwinding is effected. The rollers can be driven by an electric motor, wherein the cable is advanced by rotating the rollers.The process speed of the carriage unit may be dependent on the diameter of the cable and the roller guide may be adapted to tension or maintain tension on the cable between the feeder and the drum core during winding on the drum core.Such a carriage unit is shown in simplified form, for example, in CN 1 05 236 286 A.WO 2012 / 135 890 A1 shows a winding drum comprising a housing with a drum core mounted therein and rotatably driven, and a feed and discharge device for winding a tube in windings lying next to one another on the drum core, wherein the feed and discharge device has a guide device on which a carriage unit is driven so as to be movable in the transverse direction to the winding direction, wherein the carriage unit has a roller guide for the tube.US 2020 / 0207592 A1 also shows a device which is used for winding and unwinding cables. This apparatus has two rollers which are arranged so that a narrow gap is formed between them. The cable is passed through this gap and driven by the rollers. In order to ensure accurate positioning of the cable, a movable unit is provided which can move transversely to the winding direction and guides the cable along the nip.The cable which rests on the channel base is usually heavily soiled and is loaded with foreign bodies attached thereto. When the cable passes through a roller guide, the adhering dirt distorts the rollers and dirt accumulates in the region of the carriage unit. This can be the reason for operating failures and increased maintenance intervals, since the roller guide and the carriage unit can no longer move correctly.The object of the invention is therefore to further develop a cable drum of the type mentioned at the beginning in such a way that, taking into account a contaminated cable, reliable functioning is nevertheless possible without regular cleaning of the components.The object is achieved according to the invention by the features of the independent patent claim, while advantageous embodiments and refinements of the invention can be gathered from the dependent claims.An advantageous feature is that at least two drive rollers, which form a roller nip for the frictional drive of the cable and extend in the longitudinal direction over the entire draw-in width of the cable drum, are arranged behind a roller guide of the carriage unit which moves in the transverse direction.The location at which the cable is drawn into the nip continuously changes due to the changing position of the carriage unit relative to the rolls. The slide unit, which can preferably be moved back and forth alternately, thus ensures that a different region of the rollers is always in contact with the cable. Thus, contaminants adhering to the cable do not collect at a constant location on the rollers, but are spread, stripped and dropped across the entire width of the rollers.Thus, dirt concentration at a position of the supply and discharge device can be effectively prevented.The scraped debris can then either be collected on a debris tray, not shown, or falls out of the downwardly open cable drum. Alternatively, in the last variant, guide plates can be provided which deflect the falling dirt in a specific direction.The supply and discharge device is mounted at a radial distance from the drum core on or in the cable drum and serves for guiding and driving the cable in the longitudinal direction. The supply and discharge device consists of two side cheeks which are mounted on the housing of the cable drum at a distance from one another. A plurality of cable guide and drive bodies are mounted between the side walls, in particular the carriage unit and the at least two rollers, which form a roller gap between them, into which the cable is transferred at alternating positions starting from the carriage unit.The carriage unit moves the cable up and down along the entire length of the rolls and thus within the entire width of the nip. For this purpose, the carriage guide has at least one arm with a roller guide, which guides the cable on at least one side of the rollers. Preferably, on both sides of the rollers, an arm with a roller guide is arranged.The rollers have a rubberized and profiled surface. Owing to the rubber coating, frictional engagement between the rollers and the cable passed through therebetween is possible. Preferably, two parallel arranged and radially spaced rollers are used, which form the roller gap between them. However, more than two rollers can also be used in order to realize the wiping effect of the adhering contamination and to enable the necessary advance.The rollers bear with a predetermined force against the cable jacket. This force can be transmitted from a damper to at least one roller. Due to its damper force, the damper adjusts one roller toward the other, stationary roller in order to increase the pressure on the cable to be passed through and to ensure it in a constant manner.By rotating the rollers in opposite directions, the cable is advanced, wherein the rollers are preferably driven by an electric motor. A defined advance is thus possible during winding or unwinding of the cable on the drum core. A defined feed is understood to mean that the cable is fed to the drum core for winding up at a specific speed or is unwound from the drum core at a specific speed.At least one of the rubberised rollers has a torque sensor integrated which detects the tension load on the cable and detects whether, for example, a camera truck pulls on the cable. This tensile force is registered via the integrated torque sensor and the cable is released or the displacement of the rollers is controlled such that a defined length of cable is dispensed at a defined speed. This prevents the camera carriage from having to unwind the cable from the drum core under its own force. This is especially important since the carriage is usually located several meters away from the cable drum and otherwise would have to unwind the cable from its own drive.The drum core also has at least one torque sensor which records the tensile load and, depending on the sensor of the rollers, brakes the winding or unwinding movement, releases the drum or actively assists it by rotating. The drum core also has a drive motor, which is preferably designed as an electric motor.The sensor-based control of the rollers of the drive motors ensures that the cable is always tensioned between the supply and discharge device and the drum core and a controlled winding of the cable into windings lying next to one another is possible.Thus, the cable cannot become entangled and also does not form empty loops, as would be the case, for example, if the cable is tensioned too loosely. Stopping of the camera carriage is also detected by the sensors and possible reverse travel, which results in a drop in the tensile load of the cable on the cable drum.The at least one first drive unit of the drum core and the second drive unit of the rollers can be matched to one another in such a way that at least the first drive unit presets or fixes the winding speed and / or the unwinding speed, and the second drive unit ensures that the cable is tensioned between the carriage unit or rollers and the drum core.Between the side cheeks, a spindle is arranged transversely to the winding direction of the drum core, by means of which spindle the carriage unit which can be moved thereon can be driven. The carriage unit, which encloses the spindle by means of a sleeve-like guide unit, has rollers for guiding the cable at a distance from the spindle, which rollers are rotatably mounted on at least one arm of the carriage unit. Such rollers, which are attached to an arm of the carriage unit, can be arranged between the drum core and the rollers, as well as in front of the rollers, at the beginning of the cable drum.The carriage unit preferably has, before and after the rollers, in each case an arm with at least two rollers which are arranged perpendicularly to the rollers and laterally surround the cable.The actual position of the cable is thus controlled within the feeding and discharging device by the carriage unit, which moves back and forth between the side cheeks, on the horizontal spindle, transversely to the winding axis in the direction of the arrow.The spindle is surrounded in sections by the sleeve-like guide unit, which is a component of the carriage unit. The guide unit also has a boat which passes laterally through the sleeve body and is in positive contact with the thread profile of the spindle. The carriage unit is mounted on at least one cross-member such that it can be displaced horizontally at a distance from the spindle, wherein an arm of the carriage unit connects the guide unit to the cross-member. Below a cross member, the carriage unit continues in the vertical direction and / or with an end which is bent away therefrom and on which the rollers are mounted which ensure lateral guidance of the cable. By the position of the rollers relative to the rollers, the entry and exit position of the cable into the nip is thus controlled and continuously changed.The spindle rotates in a step-down relationship to the winding drum, always in the same direction as this. The boat of the carriage unit engages with a crescent-shaped head in the threads of the spindle, the spindle having two overlapping threads formed by a left-hand thread and a right-hand thread. After passing through a thread and reaching an end position in the region of the side walls, the boat rotates its crescent-shaped head and engages in the other thread. By this engagement of the boat with the respective thread and the rotational movement of the spindle, the direction of movement of the carriage unit is controlled.By means of the carriage unit, with which the cable can be fed in a defined manner from the drum core for winding and / or with which the cable can be unwound from the drum core in a defined manner, looping of the cable is avoided.In addition, due to the constantly changing entry point of the cable between the rollers, a point-like accumulation of dirt is avoided, whereby the longevity of the cable drum is increased.The following are shown: FIG. 1 is a perspective view illustrating aspects of the present invention FIG. 2 is a partially cut side view of the cable drum FIG. 3 is a front view of the cable drum FIG. 4 is a partially cut side view of the cable drum FIG. 5 is a partially cut perspective view of the cable drum FIG. 6 : a rear view of the supply and discharge device of the cable drum FIGS. 7 a- c : different perspective representations of the spindle driveFIG. 1 shows a cable drum 1 for pipe inspection systems, comprising a housing 2 in which an electrically driven drum core 6 for winding and unwinding a cable 5 is mounted. The drum core 6 is bounded by two lateral drum flanges 7 a, b, between which the cable 5 is wound. On the upper region of the end face 3 of the housing 2 is mounted a supply and discharge device 4 which serves for guiding and driving the cable 5.The supply and discharge device 4 consists of two side cheeks 24 a, 24 bwhich project perpendicularly from the end face 3 at a distance from one another. Between the side cheeks 24 a, b, a plurality of cable guide and drive bodies are mounted.Between the side cheeks 24 a, b, the spindle 25 is arranged parallel to the winding axis of the drum core 6, by means of which spindle the carriage unit 10 which can be moved thereon can be driven. The carriage unit 10, which encloses the spindle 25 by means of a sleeve-like guide unit 14, has, spaced apart from the spindle, the rollers 11 a, bfor guiding the cable 5 along a horizontal axis.The following explanations relate to a winding process of the cable 5 on the drum core 6, wherein the present invention also claims an unwinding process.When the cable 5 enters or exits the feeding and discharging device 4, the cable is guided between two horizontal main deflection rollers 9 aand 9 b, which ensure a controlled feeding of the cable into the feeding and discharging device. Preferably, these main deflection rollers consist of aluminum and are arranged spaced apart from one another in such a way that the cable 5 can be passed through between them and deflected in one direction. The main deflection rollers 9 a, bare rotatably mounted between the side cheeks 24 a, bvia a plurality of ball bearings.The actual position of the cable 5 is controlled within the supply and discharge device 4 by the carriage unit 10, which moves back and forth horizontally in the direction of the arrow 19 between the side cheeks 24 a, b. The carriage unit 10 has two rollers 11 a, bwhich laterally surround and guide the cable 5. These rollers 11 a, bare arranged transversely to the main deflection rollers 9 a, band are likewise rotatably mounted by means of ball bearings.By moving the carriage unit 10 between the side cheeks 24 a, band guiding the cable 5 between the rollers 11 a, b, the instantaneous position of the cable 5 within the feed and discharge device 4 can be changed.FIG. 2 shows a partial sectional view of the feeding and discharging device 4; after the rollers 11 have passed in the direction of the arrow 8, a section of the cable 5 passing through is transferred at the current position of the carriage unit 10 to two rollers 31, 32, which form the roller nip 39 between them. These rollers 31, 32 are also supported between the side cheeks 24 a, b, wherein however only the upper roller 32 is supported between the side cheeks 24 a, bin a permanent position.The lower roller 31 is supplied to the roller 32 via a hydraulic damper 35 and makes it possible to build up a pressure on the cable 5 to be passed through. The lower end of the hydraulic damper 35 is rotatably mounted and engages the arm 33 with its upper end or with the plunger 36 which presses out of the damper body. The arm 33 rotatably supported via the axis 34 guides the roller 31 connected to the arm on a circular path, wherein the roller 31 is rotatably supported on the arm at a distance from the axis 34.After the cable 5 has passed through the rollers 31, 32, it is deflected by a plurality of deflecting rollers towards the drum core 6. Thus, the direction of movement of the cable is influenced, for example, by the deflection roller 38 arranged above the cable after leaving the rollers 31, 32, and the insertion rollers 16 a, 16 barranged opposite the deflection roller 38 also make it possible to feed the cable onto the drum core 6 in a targeted manner. Laterally, the cable 5 is guided by the rollers 41 a, bwhich, like the rollers 11 a, bare rotatably fastened on the front side to an arm 44 of the carriage unit 10 and are moved together with the latter. Similarly, the feed rollers 16a, b are carried with the carriage unit 16.The carriage unit thus comprises at least two arms 12, 44 arranged on both sides of the roller nip 39, on each arm at least one roller pair 11, 41 being rotatably mounted, which laterally guides the cable 5. By means of the pairs of rollers 11, 41 lying opposite one another, the cable guided therebetween can pass through the two rollers 31, 32 in a controlled manner at a specific point of the roller nip 39.Above the deflection roller 38 is arranged the spindle 25, which is surrounded in sections by the sleeve-like guide unit 14. The guide unit 14 also has a boat 15 which passes laterally through the sleeve body and is in positive contact with the profile of the spindle 25. The slide unit 10 is mounted on the cross member 20 so as to be displaceable horizontally at a distance from the spindle 25, wherein the arm 13 of the slide unit 10 connects the guide unit 14 to the cross member 20. Below the cross-member 20, the carriage unit 10 continues in the vertical direction with a further arm 12, on the end of which, which is bent away for vertical alignment, the rollers 11 a, bare mounted.Horizontally spaced from the spindle 25, on the side lying opposite the cross member 20, the carriage unit 10 is mounted on the cross member 21, which is likewise arranged between the side cheeks 24 a, b.FIG. 3 shows a front view of the cable drum 1, wherein the passage of the cable 5 between the main deflection rollers 9 a, bcan be seen. Behind the main deflection rollers 9 a, b, the cable 5 is guided between the rollers 31, 32, which, driven by motor, pull the cable 5 in its longitudinal direction. The rollers 31, 32 have a rubber coating which is profiled in the manner of a cross in the example shown. The profiling allows the dirt adhering to the cable 5 to be stripped off.The carriage unit 10 which is driven movably along the horizontal axis in the direction of the arrow 19 is mounted on the cross member 20, wherein the carriage unit 10 determines the contact position of the cable 5 with the rollers 31, 32 or the entry of the cable into the roller nip 39. Depending on where the cable is to meet the rollers, the carriage unit 10 moves to this position and deflects the cable 5 guided between the rollers 11 a, bon the front side and on the rear side by the rollers 41 a, b. Thus, the cable 5 can be cleanly wound on the drum core 6 cleaned by the rollers.FIG. 4 shows the roller 32, to the end of which a toothed ring 42 is attached in the region of the side cheek 24. The sprocket 42 and thus also the roller 32 is rotated by the chain 43 which is driven by the drive 23. By the rotation of the roller 32 and the rubberized coating of the roller, the cable 5 abutting thereon is carried along in a frictional manner and can thus be conveyed in its longitudinal direction in the direction of the arrow 8.The drum core 6 also has a sprocket 46 in the region of the drum flange 7. By means of this chain drive 46-48, the winding and unwinding movement of the drum core 6 can be controlled.In order to keep the chain 47 always under tension, two arms 50a, b pivotably connected to the device 49, at the end of which in each case a toothed wheel 51a, b is mounted, press by means of the toothed wheels onto the inside of the chain 47. Between the arms 51a, b a damper 40 is arranged which dampens the relative movement of the arms with respect to one another.FIG. 5 shows a perspective sectional illustration of the feed and discharge device 4 with the two rollers 31, 32, wherein the rollers rotate in opposite directions. By this rotary movement, the cable 5 is conveyed through the nip 39 in the direction of the arrow 5.FIG. 6 shows a rear view of the supply and discharge device 4, it being evident that the cable 5, which is moved by the rollers 31, 32 in the longitudinal direction thereof, is taken over again by the movable carriage unit 10 after passing through the rollers in order to feed the cable to the drum core 6. For this purpose, the carriage unit 10 has the vertical rollers 41 a, bwhich engage laterally around the cable, as do the insertion rollers 16 a, bwhich engage laterally around the cable 5 from above and below and guide the lateral rollers. All these rollers are moved with the carriage unit 10 along the arrow direction 19.The lower roller 31 is pivotably mounted on the axle 34 via the arm 33. This pivoting movement is limited by the damper 35 which presses on the arm 33 via the plunger 36. As a result, the roller 31 connected to the arm 33 is moved towards the roller 32. Due to the damper 35, the gap between the rollers 31, 32 is variable to a certain extent by passing the cable 5, wherein the pressure from the damper 35 always ensures the necessary contact pressure of the rollers on the cable 5, which permits frictional engagement between cable and rollers.Figures 7a-c show various views of the spindle drive used for the horizontal movement of the carriage unit 10 along the arrow 19. For this purpose, the guide unit 14, which encloses the spindle 25 in the form of a sleeve, has a boat guide sleeve 18, into which the boat 15 can be inserted. The boat 15 has a crescent-shaped end 45 which engages the profiled surface of the spindle 25, which surface is laterally bounded by the smooth portions 25. This surface describes a left hand thread 27 and a right hand thread 28, the threads of which overlap each other. Depending on the angle of application of the crescent-shaped end 45 to the profiled surface of the spindle 25, the end 45 engages the left-hand thread 27 or the right-hand thread 28.If the spindle 25 is now driven in rotation, the crescent-shaped end 45 engages in the left-hand thread 27 or the right-hand thread 28, depending on the orientation, and as a result of this engagement in the thread turn of the rotating spindle 25, the boat 15 and the guide unit 14 connected to the boat via the boat guide sleeve are moved in the direction of the arrow 19 either to the left or to the right in the longitudinal direction of the spindle 25.The rotatable spindle 25 is mounted between the two side cheeks 24 a, bvia the ball bearings 29.Drawing Legend1 Cable drum 2 Housing 3 End side (of 2) 4 Feed and discharge device 5 Cable 6 Drum core 7 Drum flange a, b 8 Arrow direction 9 Main deflection roller a, b 10 Carriage unit 11 Rollers a, b 12 Arm 13 Arm 14 Guide unit 15 Shuttle 16 Introduction roller a, b 18 Shuttle guide sleeve 19 Arrow direction 20 Cross member 21 Cross member 23 Drive 24 Side cheek 25 Spindle 26 Smooth region 27 Left-hand thread 28 Right-hand thread 29 Ball bearing 31 Roller 32 Roller 33 Arm 34 Axis 35 Hydraulic damper 36 Ram 38 Deflection roller 39 Roller gap 40 Damper 41 Roller pair a, b 42 Toothed ring 43 Chain 44 Arm 45 Crescent-shaped end 46 Toothed ring 47 Chain 48 Pinion 49 Device 50 Arm a, b 51 Toothed wheel a, b

Claims

Cable drum (1) for pipe inspection systems, comprising a housing (2) with a drum core (6) mounted therein and rotatably driven, and an infeed and outfeed device (4) for winding a cable (5) in windings lying next to one another on the drum core (6), wherein the infeed and outfeed device (4) has a guide device (25), on which a carriage unit (10) is driven so as to be movable in the transverse direction to the winding direction, wherein a roller guide for the cable (5) is associated with the carriage unit (10), characterized in that at least two drive rollers (31, 32) forming between them a roller nip (39) for the frictional drive of the cable are arranged within the infeed and outfeed device (4), The cable reel (1) can be moved along the entire length of the drive rollers (31, 32) and has at least two arms (12, 44) arranged on both sides of the roller nip (39), and that at least one roller pair (11a, b, 41a, b) is rotatably mounted on each arm, said roller pair guiding the cable (5) laterally.Cable drum (1) according to claim 1, characterised in that the rollers (31, 32) have a rubberised and profiled surface.Cable drum (1) according to Claim 1 or 2, characterized in that the rollers (31, 32) which frictionally engage the cable (5) are driven in counterrotating rotation by a drive motor.Cable drum (1) according to one of Claims 1 to 3, characterized in that the lower roller (31) can be adjusted to the upper roller (32) via a hydraulic damper (35).Cable drum (1) according to one of Claims 1 to 4, characterized in that the inlet-side pair of rollers (41a, b) guides the cable (5) between the rollers (31, 32) and the drum core (6).Cable drum (1) according to one of Claims 1 to 5, characterized in that the guide device of the carriage unit (10) is a spindle (25).Cable drum (1) according to one of claims 1 to 6, characterised in that at least one roller (32) has an integrated torque sensor which records a tensile load on the cable (5).Cable drum (1) according to one of Claims 1 to 7, characterized in that the drum core (6) has a torque sensor.Cable drum (1) according to one of Claims 1 to 8, characterized in that a rotational direction transmitter is arranged on the carriage, said rotational direction transmitter detecting the winding direction of the cable (5) and assigning different winding torques to the drive motor of the at least one driven roller (31, 32) via a controller.Cable drum (1) according to one of Claims 1 to 9, characterized in that the driving direction signal of the carriage is used to assign different winding torques to the drive motor via a controller.

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