TOWING WINCH SYSTEM AND A METHOD TO CARRY OUT A TOWING OPERATION, IN PARTICULAR AN ESCORT OPERATION FOR ASSISTING A VESSEL IN PASSING A WATER PASSAGE

Abstract

Towing winch system 1 for controlling a render and recovery of a towline during a towing operation. The towing winch system has a control unit 6 for controlling a drive 4 and a brake 5 for respectively driving and braking the winding drum. The drive 4 comprises a plurality of brushless alternating current motors 40 which each engages in one stage by a motor gear wheel 71 to a gear wheel 70 mounted to the winding drum 3. The brake 5 comprises a plurality of brake calipers 51 which each are engageable to a brake disc 50 mounted to the winding drum 3. The drivetrain of the plurality of brushless AC motors 40, one stage gear 7 and the plurality of brake calipers 51 form a powerful and robust structure to operate the towing winch system 1 under severe conditions which may occur in a towing operation.

Claims

1-18. (canceled)

19. A towing winch system configured to control a render and recovery of a towline in between a vessel and a towboat during a towing operation, in particular an escort operation, which towing winch system comprises: a framework for supporting winch components; a winding drum for winding and unwinding the towline in which the winding drum is rotatable supported by the framework, in which the winding drum has a drum forming a winding space in between a first and second winding drum flange for enclosing the towline; a drive directly connected by a one-stage gear to the winding drum for rotating the winding drum for hauling in the towline, wherein the one-stage gear comprises a gear wheel mounted to the winding drum; a brake connected to the winding drum for braking the winding drum for holding or paying out the towline, wherein the winding drum is positioned in between the drive and the brake, wherein the brake disc is mounted to one of the drum flanges and the gear wheel is mounted to the other one of the drum flanges; and a control unit for controlling the drive and the brake based on an input signal indicative of a torque exerted by the towline on the winding drum; wherein the drive comprises a plurality of brushless alternating current motors, wherein each motor has a motor housing and a motor output shaft provided with a motor gear wheel which engages to the gear wheel mounted to the winding drum, wherein the brake comprises at least one brake disc and a plurality of brake calipers in which each brake caliper is provided with a pair of brake pads for engaging the at least one brake disc, wherein the plurality of motor gear wheels and the plurality of brake calipers are all positioned in a lower half region of the gear wheel such that the gear wheel can be lifted from the framework without demounting the motors, wherein the framework comprises a mainframe and a brake frame being arranged for supporting the plurality of brake calipers, and wherein the brake frame is releasably connectable to the mainframe.

20. A render and recovery winch system for controlling a render and recovery of a towline in between a vessel and a towboat during a towing operation, in particular an escort operation, which render and recovery winch system comprises: a framework for supporting winch components; a winding drum for winding and unwinding the towline in which the winding drum is rotatable supported by the framework, in which the winding drum has a drum forming a winding space in between a first and second winding drum flange for enclosing the towline; a drive connected by a one-stage gear to the winding drum for rotating the winding drum for hauling in the towline, wherein the one-stage gear comprises a gear wheel mounted to the winding drum; a brake connected to the winding drum for braking the winding drum for holding or paying out the towline; and a control unit for controlling the drive and the brake based on an input signal indicative of a torque exerted by the towline on the winding drum; wherein the drive comprises a plurality of brushless alternating current motors, wherein each motor has a motor housing and a motor output shaft provided with a motor gear wheel which engages to the gear wheel mounted to the winding drum, and wherein the brake comprises at least one brake disc and a plurality of brake calipers in which each brake caliper is provided with a pair of brake pads for engaging the at least one brake disc.

21. The render and recovery winch system according to claim 20, wherein the motor has a motor rotor provided with at least 8 permanent magnets.

22. The render and recovery winch system according to claim 20, wherein the drum is rotatable supported by a horizontally arranged drum shaft, wherein the winding drum shaft is supported by the framework.

23. The render and recovery winch system according to claim 22, wherein the drum shaft is arranged stationary.

24. The render and recovery winch system according to claim 20, wherein the gear wheel is mounted to the drum, in particular to one of the drum flanges of the drum.

25. The render and recovery winch system according to claim 20, wherein each motor gear wheel engages to an outer toothed circumferential surface of the gear wheel.

26. The render and recovery winch system according to claim 20, wherein the brake frame is L-shaped, more in particular U-shaped, comprising an inner mounting surface for positioning the plurality of brake calipers, such that the brake calipers are positioned at an outer circumference of the brake disc of the render and recovery winch system.

27. The render and recovery winch system according to claim 20, wherein the framework, in particular the brake frame, comprises at least one load sensor for measuring a force inducted by a brake caliper.

28. The render and recovery winch system according to claim 27, wherein the mainframe comprises a base plate, wherein an upper portion of the mainframe is pivotally connected to the base plate about a pivot axis, wherein the at least one load sensor, in particular two load sensors, is positioned in between the upper portion and the base plate at a distance from the pivot axis.

29. The render and recovery winch system according to claim 20, wherein at least one of the drum flanges has a coding, in particular a colour coding for visually indicating a winding zone of the winding space.

30. A towboat for towing a floating object, in particular an escort tug for escorting a vessel, comprising a render and recovery winch system according to claim 20.

31. An assembly of a towboat according to claim 30 and a floating object interconnected by a towline.

32. A method for towing a floating object by a towboat, in particular an escort method for assisting a vessel by a towboat in passing a water passage, wherein use is made of a render and recovery or towing winch system according to claim 20, wherein the method comprises steps of: interconnecting the floating object, in particular the vessel to be escorted and the towboat, in particular an escort tug, by a towline; measuring an occurring torque exerted by the towline on a winding drum of the render and recovery winch system; controlling a drive of the render and recovery winch system to rotate the winding drum for hauling in the towline; and controlling a brake of the render and recovery winch system to brake the winding drum for holding or paying out the towline.

33. The method according to claim 32, wherein only a portion of a plurality of brake calipers and/or motors is activated to respectively brake or drive the winding drum.

34. The method according to claim 32, wherein the towing method is an escort method for escorting a vessel by the towboat.

Description

[0069] The invention will be explained in more detail with reference to the appended drawings. The drawings show a practical embodiment according to the invention, which may not be interpreted as limiting the scope of the invention. Specific features may also be considered apart from the shown embodiment and may be taken into account in a broader context as a delimiting feature, not only for the shown embodiment but as a common feature for all embodiments falling within the scope of the appended claims, in which:

[0070] FIGS. 1 and 2 show perspective views of a towing winch system according to the invention;

[0071] FIG. 3 shows the towing winch system of FIG. 1 in an exploded view;

[0072] FIG. 4-6 show orthogonal views of the towing winch system of FIGS. 1-3; and

[0073] FIG. 7 shows a brake frame of the towing winch system.

[0074] Identical reference signs are used in the drawings to indicate identical or functionally similar components. In this description, vertical and horizontal are referred to as planes or directions in their ordinary meaning. Directions related to the vessel or towboat defined by horizontally or vertically are taken when the vessel or boat is in a position afloat, in a normal, stabilised position.

[0075] FIG. 1 and FIG. 2 show in perspective views a towing winch system 1 according to the invention. FIG. 3 shows an exploded view of the towing winch system and FIGS. 4-6 show respectively a frontal, top and side view of the towing winch system. The towing winch system is configured for carrying out a towing operation, in particular an escort operation.

[0076] In comparison with other operations, like anchoring and mooring, towing operations are typically carried out with relative long horizontally extending towlines. In an escort operation, typically, a towline of at least 100 meters is arranged in between a towboat and a floating object, e.g. a tanker or a vessel. The towboat is manoeuvring to guide the vessel along a predetermined trajectory. During these escort operations, to prevent slack, the towline should be kept under tension. On the one hand, to prevent a breakage of the towline, the tension may not exceed a certain value. Attention should be paid in that high tensions may occur abruptly, and the towing winch system should respond accordingly. On the other hand, to prevent slack, the towline may not hang loose in between the floating object and the towboat. In such a situation, the towing winch system should wind the towline at high speeds. Hence, to perform in escort operations, the towing winch system 1 is required to resist high occurring peak loads of for example 100 to 300 tonnes and at the same time the towing winch system is required to respond with high rotational speeds in both directions to compensate large towline lengths when slacking occurs.

[0077] The towing winch system 1 according to the invention is configured to perform under these heavy circumstances occurring in a towing operation. The towing winch system 1 comprises a framework 2 for holding a winding drum 3, a drive 4, a brake 5 and a gear 7. A control unit 6 is provided to control the towing winch system.

[0078] In the illustrated embodiment of FIG. 1-6, the winding drum 3 is positioned in between the drive 4 and the brake 5. Alternatively, the drive and brake may both be positioned at one end of the winding drum.

[0079] The drive 4 is connected by the gear 7 to the winding drum 3 for accelerating the winding drum. The brake 5 comprises a brake disc 50 which is connected to the winding drum 3 and a plurality of brake calipers 51 to engage the brake disc 50, which brake calipers 51 are connected to the framework 2, such that the winding drum 3 can be decelerated by the brake 5. The drive 4 and the brake 5 are operatively connected to the control unit 6. The control unit 6 is programmed to control the rotation of the winding drum 3 by controlling the drive 4 and the brake 5. The plurality of brake calipers 51 is beneficial in controlling the deceleration of the winding drum by allowing one or more brake calipers 51 to engage the brake disc. By varying the amount of active brake calipers 51, the winding drum 3 can be decelerated in dependence of occurring circumstances during an escort operation.

[0080] The drive 4 driving the winding drum 3 is an electrical drive. Here, the drive 4 is fully electric. The drive 4 comprises a plurality of brushless alternating current motors 40. Each motor 40 has its own motor housing 41 and motor output shaft 42. The plurality of electric motors 40 is beneficial, because by activating a selection of one or more motors, the towing winch system is configured to anticipate on different situations occurring during an escort operation.

[0081] The motor 40 is a brushless AC motor, also called a permanent magnet synchronous motor PMSM. The motor has a motor rotor provided with permanent magnets to provide a magnetic field. The motor rotor is carrying an amount of permanent magnets. Preferably, the permanent magnets are equally spaced in a circular array at an outer circumferential surface of the motor rotor. The permanent magnets define an amount of motor poles of the motor. In particular, the motor rotor has at least 8 motor poles. Preferably, the motor rotor has at least 16 motor poles. A large amount of motor poles may be beneficial to obtain a substantially constant driving torque. Advantageously, the at least 16 motor poles contribute in providing a high-torque which remains available over a wide range of rotating speeds of the winding drum.

[0082] Preferably, the permanent magnets contain neodymium. Preferably, the permanent magnets are Neodymium-Iron-Boron magnets. Advantageously, a neodymium containing magnet contributes to a more powerful motor.

[0083] The motor 40 has a motor housing for housing a plurality of field coils. The motor rotor is driveable by the plurality of field coils. The field coils form a motor stator. The field coils are preferably situated around a circumference of the motor rotor. The amount of field coils corresponds with the amount of motor poles.

[0084] FIG. 3 shows the towing winch system 1 of FIG. 1 in an exploded view. The towing winch system has a framework 2 which is mountable to a deck of a towboat. The framework 2 is arranged for housing winch components of the towing winch system 1. Here, the framework 2 has a modular configuration. The framework 2 is assembled by a mainframe 20, a brake frame 21 and a drum frame 22.

[0085] The mainframe 20 is block-shaped and assembled by a bottom plate 200, a left and right side plate 220, a front plate 230 and a back plate 240. The plates forming the mainframe 20 provide an inner space for receiving the winch components.

[0086] The mainframe 20 further comprises a base plate 250. The mainframe 20 is pivotally connected to the base plate 250. The mainframe 20 is pivotable with respect to the base plate 215 about a pivot axis 251. The pivot axis A-A extends in a horizontal direction transversal the mainframe 20. The pivot axis extends from the left to the right side plate 220. At least one load sensor 60 is positioned in between the bottom plate 200 and the base plate 250 for measuring a load during a towing operation. The at least one load sensor 60 is positioned at a distance from the pivot axis A-A. During a towing operation, tension forces on the towline will exert a torque on the drum 30 which will be deducted by the brake 5 to the framework 2 and measured by the at least one load sensor 60. Here, the pivot axis 251 comprises a pivot shaft which is mounted at a back region of the mainframe 20. Here, as shown in FIG. 4, two load sensors 60 are mounted at a front region of the mainframe 20. At least two load sensors are beneficial to obtain multidirectional load data.

[0087] Each side plate 220 is provided with a winch shaft support 221 for supporting a drum shaft 33. Here, the drum shaft 33 is arranged stationary. The drum 30 is rotatable with respect to the drum shaft 33. A left and right winch shaft lock 222 are provided to clamp the drum shaft 33 to the winch shaft supports 221 of the side plates 220 of the mainframe 20.

[0088] The winding drum 3 is arranged for winding and unwinding a towline. The winding drum comprises a drum 30 which has a winding zone 320 in between a first and second drum flange 31, 32. Here, at least one of the first and second drum flanges 31, 32 is provided with a visual winding indicator to indicate a predetermined winding area. Preferably, the visual winding indicator of a drum flange 31, 32 is provided by a two-colour indicator consisting of two visually distinct colours, e.g. a black and yellow colour. The yellow colour at a bottom region of the winding zone may indicate a sub-area of the winding zone which should always remain wound during operation. The drum 30 is supported by a drum bearing 34 which is mounted to the drum 30. The drum shaft 33 is supported by the framework 2 at a first and second winch shaft support 221.

[0089] FIG. 3 further shows the gear, which gear 7 is a one-stage gear. The gear 7 provides a direct drive of the winding drum 3. The gear 7 provides a one-step reduction of an applied rotational speed of the motor output shaft 42 to a rotational speed of the winding drum 3. The gear 7 provides a gear ratio of at least 15:1 in one stage.

[0090] The gear 7 comprises a gear wheel 70 which is fixed to the first drum flange 31. The gear wheel 70 and the connected winding drum 3 is driveable by engaging motor gear wheels 71. Each motor gear wheel 71 is directly mounted to a motor output shaft 42 of a motor 40. The gear wheel 70 may have a toothed inner surface to be engaged. Preferably, the gear wheel 70 has a toothed outer surface, wherein the motor gear wheels 71 engage from the outside onto the gear wheel 70. Advantageously, the arrangement of the gear wheels 71 outside the gear wheel 70 allow a quick removal of the gear wheel in maintenance, while keeping the motors 40 mounted to the side plate 220.

[0091] In addition, the motors 40 are positioned in an arch shaped array. Preferably, the arch shaped array does not extend outside a lower half of a circular array which is beneficial in maintenance of the towing winch system in allowing the winding drum 3 to be lifted from the winch shaft support 221 without any need for demounting any of the motors 40.

[0092] As shown in FIG. 3, here, a motor plate 49 is provided for mounting a motor 42 to a side plate 220, also called motor side plate, of the framework 2. The motor plate 49 may be integral with or separately connectable to the motor housing 41 of the motor 40. The motor plate 49 allows a quick and easy adjustable mounting of the motor 40 to the motor side plate 220.

[0093] The motor side plate 220 comprises a plurality of motor apertures which each provide a through for each motor output shaft 42 of each mounted motor 40. The motor 40 is mountable to the motor aperture by its motor plate 49. As seen above, each motor output shaft 42 is provided with a motor gear wheel 71. After assembly, the motor gear wheel 71 is positioned in the inner space of the mainframe 20 inside a gear compartment 27. The gear compartment 27 is configured for housing the gear wheel 70 of the gear 7. The gear compartment 27 is covered by a gear cover 79 to enclose the gear wheel 70.

[0094] As shown in FIG. 1-6, the brake 5 is positioned with respect to the drive 4 at an opposite side of the winding drum 3. The brake disc 50 is fixed to the second drum flange 32 of the winding drum 3.

[0095] In operation, the brake disc 50 rotates together with the winding drum 3. Brake calipers 51 are positioned at a circumference of the brake disc 50. Each brake caliper 51 is provided with a pair of brake pads 52 to engage the flat end surfaces of the brake disc 50. Preferably, the brake calipers 51 are positioned in a similar way as the motors 40 which is beneficial in servicing the towing winch system. The brake calipers 51 are positioned in an arch shaped array. Preferably, the arch shaped array is bounded within a lower half of a circular array to allow an upwards removal of the brake disc 50 during maintenance, while keeping the brake calipers 51 mounted at their position.

[0096] FIG. 7 shows a subassembly of the brake frame 21 and brake calipers 51 in a separate view. The plurality of brake calipers 51 is mounted to the brake frame 21. The brake frame 21 is U-shaped. The U-shaped brake frame 21 comprises an inner mounting surface for mounting the plurality of brake calipers 51. The U-shaped brake frame 21 has upstanding U-legs 210 interconnected by an U-bridge portion 211. The U-legs form an in between space for receiving the brake disc 50. The brake disc 50 can be lowered into the space, such that the brake disc 50 is engageable by each brake caliper 51.

[0097] One of the U-legs 210 is provided with a distributor 53 for hydraulically connecting the plurality of brake calipers 51. The distributor 53 provides a central hydraulic connector for controlling the plurality of brake calipers 51. The releasable subassembly of the brake frame 21 is beneficial in servicing the towing winch system.

[0098] As shown in FIG. 7, in an alternative embodiment, the brake frame 21 may be provided with a load sensor 60. The load sensor 60 is configured to measure a deformation of the brake frame 21. In operation, the deformation is caused by tension forces exerted by the towline on the winding drum 3. The measured deformation is indicative of a torque acting on the winding drum 3 and transferred to the brake frame 21 via the drum 30, the connected brake disc 50 and the engaging brake calipers 51. Preferably, the load sensor 60 is positioned at a lower region, in particular at a corner position, of the U-shaped brake frame 21.

[0099] Numerous variants are possible in addition to the embodiment shown in the figures. In a variant of the illustrated embodiment of the drum in between the drive and brake, in an alternative embodiment, the drive and brake may be both positioned at one side of the drum. In an alternative embodiment, the brake may comprise more than one brake disc which may each in engagement with a group of brake calipers.

[0100] Although the present invention has been described in detail, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the scope of the invention as hereinafter claimed. It is intended that all such changes and modifications be encompassed within the scope of the present disclosure and claims.

[0101] Thus, the invention provides a towing winch system for controlling a render and recovery of a towline during a towing operation. The towing winch system has a control unit for controlling a drive and a brake for respectively driving and braking the winding drum. In a first aspect, the drive comprises a plurality of brushless alternating current motors which each engages in one stage by a motor gear wheel to a gear wheel mounted to the winding drum. The brake comprises a plurality of brake calipers which each are engageable to a brake disc mounted to the winding drum. The drivetrain of the plurality of brushless AC motors, one stage gear and the plurality of brake calipers form a powerful and robust structure to operate the towing winch system 1 under severe conditions which may occur in a towing operation.

TABLE-US-00001 Reference signs list: 1 towing winch system 2 framework 3 winding drum 4 drive 5 brake 6 control unit 7 gear 20 main frame 200 bottom plate 220 side plate 221 winch shaft support 222 winch shaft lock 230 front plate 231 towline aperture 240 back plate 250 base plate 251 pivot axis A-A 21 brake frame 210 U-leg 211 U-bridge portion 22 drum frame 27 gear compartment 30 drum 31 first drum flange 32 second drum flange 320 winding zone 33 drum shaft 34 drum bearing 40 motor 41 motor housing 42 motor output shaft 49 motor plate 50 brake disc 51 brake caliper 52 brake pad 53 distributor 60 load sensor 70 gear wheel 71 motor gear wheel 79 gear cover