Method and system for controlling the hoisting height of winches applicable to overhead vertical wharves

Abstract

This invention discloses a method and system for controlling the lifting height of a winch in an overhead vertical dock. The method includes: determining the target cable length of the winch based on the target descent position of the cargo lifting device; driving the winch to lay the cable through a control unit and acquiring the readings of the absolute encoder in the winch in real time; calculating the actual cable length of the winch based on the real-time acquired absolute encoder readings; and stopping the cable laying by driving the winch through the control unit when the actual cable length reaches the target cable length. This invention calculates the actual cable length of the winch by acquiring the readings of the absolute encoder in the winch in real time, and controls the winch's cable retrieval and laying accordingly. It can accurately stop the winch when the actual cable length reaches the target cable length, allowing the cargo lifting device to stop at the target descent position, thus achieving precise and flexible control of the winch's lifting height.

Description

Technical Field

[0001] This invention relates to the field of dock equipment technology, and in particular to a winch lifting height control method and system suitable for overhead vertical docks. Background Technology

[0002] There is a certain distance between the cargo on the ship and the dock platform. If the cargo is transported directly from the ship's deck to the dock by crane, it will affect the flow of passengers on deck, and the flow of passengers and the loading and unloading of cargo cannot be carried out simultaneously, resulting in low efficiency in both cargo loading / unloading and passenger flow. On the other hand, if a corresponding channel for receiving cargo is built at the dock, the water level where the ship is located will affect the normal operation of the channel, making it difficult to ensure the safe and efficient loading and unloading of cargo. In the prior art, a dock cargo lifting device has been proposed, which sets up a shaft inside the dock and houses the cargo lifting device within the shaft.

[0003] In river areas with large fluctuations in water level, the above-mentioned equipment can be used for cargo transportation in elevated vertical wharves. However, due to the influence of large changes in water level and ship height, the height difference between the wharf plane and the ship deck also changes, and the lifting height of cargo transportation changes quite frequently. Therefore, when using the above-mentioned equipment for cargo transportation, there is an urgent need for a flexible and accurate method to control the lifting height. Summary of the Invention

[0004] In view of the above-mentioned defects or improvement needs of the existing technology, the purpose of this invention is to provide a winch lifting height control method and system suitable for overhead vertical docks.

[0005] To achieve this objective, the present invention adopts the following technical solution:

[0006] This invention provides a method for controlling the hoisting height of a winch suitable for overhead vertical piers, comprising:

[0007] Determine the target cable length for the winch based on the target descent position of the cargo hoisting device;

[0008] The control unit drives the winch to release the cable and obtains the readings of the absolute encoder in the winch in real time.

[0009] The calculation unit calculates the actual cable length released by the winch based on the real-time readings of the absolute encoder.

[0010] When the actual cable length reaches the target cable length, the winch is driven by the control unit to stop cable laying.

[0011] Furthermore, the step of calculating the actual cable length released by the winch based on the real-time readings of the absolute encoder includes:

[0012] Obtain the initial reading of the absolute encoder when the cargo lifting device is in its initial position;

[0013] Based on the initial reading and the real-time reading, determine the number of cable turns of the winch:

[0014] ΔN k =N k -N0;

[0015] Where, ΔN k Let N be the number of cable turns made by the winch at time k. k Let k be the reading of the absolute encoder at time k, and N0 be the initial reading of the absolute encoder.

[0016] Furthermore, the step of calculating the actual cable length released by the winch based on the real-time readings of the absolute encoder also includes:

[0017] The number of cable layers in the winch is determined based on the number of cable turns.

[0018] The actual cable length is calculated based on the number of cable turns and the number of cable layers.

[0019] Further, the step of determining the number of cable layers in the winch based on the number of cable turns includes:

[0020] If the number of cable turns satisfies:

[0021]

[0022] Among them, a i The number of turns of the i-th layer of cable on the winch drum when the cargo lifting device is in the initial position; the n-th layer is the n-th layer on the winch drum; and the m-th layer is the outermost layer on the winch drum when the cargo lifting device is in the initial position.

[0023] This confirms that the cable in the winch has been lowered to the nth layer.

[0024] Further, the step of calculating the actual cable length based on the number of cable turns and the number of cable layers includes:

[0025] Determine the diameter of the circle containing each layer of cable on the winch drum using the calculation formula:

[0026]

[0027] Calculate the actual cable length based on the number of cable loops, the number of cable layers, and the diameter of the circle containing each layer of cable:

[0028]

[0029] Among them, Di Let L be the diameter of the circle containing the i-th layer of cable, D be the diameter of the winch drum, d be the diameter of the winch cable, and L be the diameter of the winch cable. f(k) Let L be the actual cable length laid by the winch at time k. all D is the total length of the winch cable. n Let L be the diameter of the circle containing the nth layer of cable. t This refers to the length of the cable from the winch drum to the cargo lifting device when the lifting device is in its initial position.

[0030] Furthermore, the control method further includes:

[0031] Real-time acquisition of winch cable tension;

[0032] Based on the cable tension, determine whether the loading capacity of the cargo lifting device exceeds the rated carrying capacity; if it does, an alarm will be triggered.

[0033] Furthermore, the step of acquiring the cable tension of the winch in real time includes:

[0034] Obtain the force value of the pin sensor;

[0035] Calculate the cable tension of the winch based on the force value of the pin sensor:

[0036]

[0037] Among them, F c(k) Let F be the cable tension at time k. P(k) Let δ be the force value of the pin sensor at time k, and δ be the force coefficient ratio.

[0038] Furthermore, the control method further includes:

[0039] When the loading of cargo is detected to be complete, the control unit drives the winch to take up the cable and obtains the reading of the absolute encoder in the winch in real time.

[0040] When the absolute encoder reading is the same as the initial reading, the control unit drives the winch to stop winding the cable.

[0041] The present invention also provides a winch lifting height control system suitable for overhead vertical docks, including a control unit, a winch, a cargo lifting device and a computing unit;

[0042] The control unit is used to drive the winch to release and retrieve the cable;

[0043] The winch includes a cable and an absolute encoder, wherein the cable is connected to the cargo lifting device, and the absolute encoder is used to obtain the number of turns of the cable.

[0044] The calculation unit is used to calculate the length of the winch cable in real time based on the reading of the absolute encoder.

[0045] Furthermore, the control system also includes a pin sensor connected to the cable, used to detect whether the loading capacity of the cargo lifting device exceeds the rated carrying capacity.

[0046] The beneficial effects of this invention are:

[0047] This invention provides a method and system for controlling the lifting height of a winch suitable for an overhead vertical dock. The method includes: determining the target cable laying length of the winch based on the target descent position of the cargo lifting device; driving the winch to lay the cable through a control unit and acquiring the reading of the absolute encoder in the winch in real time; calculating the actual cable laying length of the winch based on the real-time acquired absolute encoder reading; and stopping the cable laying by driving the winch through the control unit when the actual cable laying length reaches the target cable laying length.

[0048] This invention calculates the actual cable length of the winch by acquiring the reading of the absolute encoder in the winch in real time, and controls the winch's cable gathering and releasing accordingly. When the actual cable length of the winch reaches the target cable length, it can stop accurately, so that the cargo lifting device can stop at the target descent position, achieving precise and flexible control of the winch's lifting height.

[0049] Additional aspects and advantages of this application will be set forth in part in the description which follows, and will become apparent from the description or may be learned by practice of this application. Attached Figure Description

[0050] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein:

[0051] Figure 1 This is a schematic diagram of a winch lifting height control method applicable to an overhead vertical wharf in an embodiment of the present invention;

[0052] Figure 2 This is a schematic diagram of the winch operation in an embodiment of the present invention;

[0053] Figure 3 This is an axial sectional view of the winch drum in an embodiment of the present invention;

[0054] Figure 4 This is a schematic diagram of the tension of the winch cable in an embodiment of the present invention;

[0055] Figure 5 This is a schematic diagram of a winch lifting height control system applicable to an overhead vertical wharf in an embodiment of the present invention. Detailed Implementation

[0056] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0057] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0058] Those skilled in the art will understand that, unless otherwise stated, the singular forms “a,” “an,” “the,” and “the” used herein may also include the plural forms. It should be further understood that the word “comprising” as used in the specification of this application means the presence of the stated features, integers, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or combinations thereof.

[0059] It will be understood by those skilled in the art that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. It should also be understood that terms such as those defined in general dictionaries should be understood to have the same meaning as in the context of the prior art, and should not be interpreted in an idealized or overly formal sense unless specifically defined as in the embodiments of this application.

[0060] This embodiment provides a winch lifting height control method and system suitable for overhead vertical wharves, applied to cargo lifting at overhead vertical wharves in areas with large water level differences.

[0061] The flowchart of the winch lifting height control method for overhead vertical wharves provided in this embodiment is as follows: Figure 1 As shown, the control method includes steps S10-60. In this embodiment, a schematic diagram of the winch operation is shown below. Figure 2 As shown, the winch is located on the wharf plane, and the cable in the winch is connected to the cargo lifting device, which is located in a shaft arranged along the height direction of the wharf.

[0062] S10. Determine the target cable length of the winch based on the target descent position of the cargo lifting device.

[0063] It should be noted that in this embodiment, the target descent position of the cargo lifting device is at the same height as the deck of the berthed ship, that is, at the same level in the horizontal direction, and the length of the winch cable laid down from the dock surface to the target descent position is the target cable laying length.

[0064] S20. Drive the winch to release the cable through the control unit and obtain the reading of the absolute encoder in the winch in real time.

[0065] See Figure 2 In this embodiment, the winch includes a drum, a cable, and an absolute encoder. The control unit drives the drum to rotate to achieve cable winding and unwinding, thereby driving the lifting device connected to the cable to rise and fall. The absolute encoder is used to count the number of rotations of the drum, and the reading of the absolute encoder reflects the number of rotations of the winch drum.

[0066] In this embodiment, the actual cable length of the winch is obtained by real-time acquisition of the absolute encoder reading and calculation conversion. When the actual cable length reaches the target cable length, it means that the cargo lifting device has descended to the target descent position.

[0067] S30. The calculation unit calculates the actual cable length of the winch based on the real-time readings of the absolute encoder.

[0068] S301. Obtain the initial reading of the absolute encoder when the cargo lifting device is in the initial position.

[0069] S302. Determine the number of cable turns of the winch based on the initial and real-time readings:

[0070] ΔN k =N k -N0;

[0071] Where, ΔN k Let N be the number of cable turns made by the winch at time k. k Let k be the reading of the absolute encoder at time k, and N0 be the initial reading of the absolute encoder.

[0072] Generally, when the cargo lifting device is in its initial position, the initial reading of the absolute encoder in the winch is zero. However, in some winches, the reference plane of the cargo lifting device is set in a different position, in which case the initial reading of the absolute encoder when the cargo lifting device is in its initial position will be non-zero.

[0073] Understandably, after determining the number of cable turns released by the winch, a mathematical formula can be established based on the diameter of each cable turn to calculate the actual cable length released by the winch.

[0074] See Figure 3When the winch drum has multiple layers of cable wound around it, the diameter of the circle corresponding to each layer of cable is different. Therefore, it is necessary to calculate the diameter of each layer separately.

[0075] S303. Determine the number of cable layers in the winch based on the number of cable turns.

[0076] If the number of cable turns satisfies:

[0077]

[0078] Among them, a i The number of turns of the i-th layer of cable on the winch drum when the cargo lifting device is in the initial position is denoted by , the n-th layer is the nth layer on the winch drum, and the m-th layer is the outermost layer on the winch drum when the cargo lifting device is in the initial position.

[0079] This confirms that the cable in the winch has been lowered to the nth layer.

[0080] For example, if the initial position of the cargo lifting device is that the winch drum has seven layers of cable wound around it, then the value of m is 7, meaning the seventh layer is the outermost layer on the winch drum when the cargo lifting device is in its initial position. Further, if in this winch, a7 equals 10 and a6 equals 11, at a certain moment, when the number of cable turns is 5, the number of cable turns is less than a7. At this time, n equals 7, meaning the cable in the winch has been laid to the 7th layer. Similarly, at another moment, when the number of cable turns is 15, the following condition is met:

[0081]

[0082] At this point, n equals 6, meaning the cable in the winch has been lowered to the 6th level.

[0083] Understandably, in practical applications, when each winch is in its initial position, the number of turns of cable wound on each layer of the drum is fixed. Therefore, {a1, ... a m The value of} can be pre-stored in the computing unit as a configuration.

[0084] S304. Calculate the actual cable length based on the number of cable turns and cable layers.

[0085] See the axial section of the winch drum. Figure 3 Based on the geometric characteristics of cable winding, a mathematical formula for the diameter of the circle containing each layer of cable is established.

[0086] Determine the diameter of the circle containing each layer of cable on the winch drum using the calculation formula:

[0087]

[0088] Among them, D i Let d be the diameter of the circle containing the i-th layer of cable, D be the diameter of the winch drum, and d be the diameter of the winch cable.

[0089] Furthermore, based on the formula for the diameter of the circle containing each layer of cable, the number of cable turns in the winch, and the number of cable layers, the remaining cable length on the winch drum can be calculated:

[0090]

[0091] Among them, L r(k) Let k be the remaining cable length on the winch drum.

[0092] Continuing with the example where the cargo hoisting device is initially positioned with seven layers of cable wound around the winch drum, a7 equals 10, a6 equals 11, and the number of cable turns is 15, the remaining cable length on the winch drum is:

[0093]

[0094] It is understandable that in the above formula The item represents the remaining cable length in the sixth layer. The term represents the total remaining cable length in the first to fifth layers, and the sum of the two is the remaining cable length on the drum.

[0095] Furthermore, based on the number of cable loops, the number of cable layers, and the diameter of the circle containing each layer of cable, the actual cable length is calculated:

[0096]

[0097] Among them, L f(k) Let L be the actual cable length laid by the winch at time k. all D is the total length of the winch cable. n Let L be the diameter of the circle containing the nth layer of cable. t This refers to the length of the cable from the winch drum to the cargo lifting device when the lifting device is in its initial position.

[0098] S40. When the actual cable length reaches the target cable length, the winch is driven by the control unit to stop cable laying.

[0099] When the actual cable length reaches the target cable length, it indicates that the cargo lifting device has reached the target descent position. At this time, the winch is driven by the control unit to stop cable laying, so that cargo can be loaded.

[0100] S50. When the loading of the cargo is detected to be complete, the control unit drives the winch to take up the cable and obtains the reading of the absolute encoder in the winch in real time.

[0101] S60. When the absolute encoder reading is the same as the initial reading, the control unit drives the winch to stop winding the cable.

[0102] Understandably, when the absolute encoder reading is the same as the initial position, the cargo lifting device returns to the dock level, at which point the control unit drives the winch to stop winding up the cable.

[0103] If the unloading position of the cargo hoisting device is not on the dock level, the target hoisting height of the winch can be determined based on the relative height between the unloading position and the dock level. Similarly, the actual hoisting height of the winch is controlled to match the target hoisting height by real-time acquisition of absolute encoder readings.

[0104] Furthermore, the control method in this embodiment also includes detecting the loading amount of the cargo lifting device through a pin sensor and issuing an overload alarm.

[0105] Specifically, the tension diagram of the winch cable is as follows: Figure 4 As shown, in this embodiment, the force value of the pin sensor is obtained, and the cable tension of the winch is calculated based on the force value of the pin sensor:

[0106]

[0107] Among them, F c(k) Let F be the cable tension at time k. P(k) Let δ be the force value of the pin sensor at time k, and δ be the force coefficient ratio.

[0108] This allows for real-time acquisition of the winch cable tension, which in turn determines whether the load capacity of the cargo lifting device exceeds the rated carrying capacity. If it does, an alarm is triggered.

[0109] This embodiment also provides a winch lifting height control system suitable for overhead vertical wharves, as shown in the schematic diagram below. Figure 5 As shown.

[0110] Specifically, the winch lifting height control system for overhead vertical docks in this embodiment includes a control unit, a winch, a cargo lifting device, a computing unit, and a pin sensor.

[0111] In this embodiment, the winch includes a winch body, which comprises a motor assembly, drums, and a frequency converter drive assembly. Further, the motor assembly includes a geared motor, a reducer, an incremental encoder, and an electromagnetic brake. The drums consist of a first drum with rope grooves, a second drum with rope grooves, a third drum with rope grooves, a fourth drum with rope grooves, a partition, an electromagnetic self-braking safety brake, and an absolute encoder. The motor assembly is connected to the drum assembly via a coupling.

[0112] The variable frequency drive assembly includes a variable frequency drive cabinet, which is connected to the gear motor via cables.

[0113] In this embodiment, the winch also includes a cable, which is connected to the cargo lifting device.

[0114] Understandably, in this embodiment, the control unit is used to drive the winch to release and retrieve the cable. When the winch drum rotates, the absolute encoder simultaneously counts and is used to obtain the number of turns of the cable released.

[0115] The calculation unit is used to calculate the length of the winch cable in real time based on the readings of the absolute encoder.

[0116] Furthermore, the control system also includes a pin sensor, which is connected to a cable and is used to detect whether the load of the cargo lifting device exceeds the rated carrying capacity.

[0117] It should be understood that although the steps in the flowcharts of the accompanying figures are shown sequentially as indicated by the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the accompanying figures may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times, and their execution order is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the sub-steps or stages of other steps.

[0118] The above description is only a partial embodiment of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this application, and these improvements and modifications should also be considered within the scope of protection of this application.

Claims

1. A method for controlling the hoisting height of a winch suitable for overhead vertical wharves, characterized in that, A winch is installed on the wharf plane, and a cargo hoisting device is installed in a shaft arranged along the height of the wharf. The winch includes a drum, a cable, and an absolute encoder. The cable is wound around the drum and connected to the cargo hoisting device. The absolute encoder is used to count the number of rotations of the drum. The method includes: The target cable length of the winch is determined based on the target descent position of the cargo lifting device, wherein the target descent position is the position flush with the deck of the berthed vessel. The control unit drives the winch to release the cable and obtains the readings of the absolute encoder in the winch in real time. The calculation unit calculates the actual cable length released by the winch based on the real-time readings of the absolute encoder. When the actual cable length reaches the target cable length, the winch is driven by the control unit to stop cable laying. The step of calculating the actual cable length of the winch based on the real-time readings of the absolute encoder includes: Obtain the initial reading of the absolute encoder when the cargo lifting device is in its initial position; Based on the initial reading and the real-time reading, determine the number of cable turns of the winch: = - ; in, Let k be the number of cable turns made by the winch at time k. The absolute encoder reading at time k. This is the initial reading for the absolute encoder; The step of calculating the actual cable length of the winch based on the real-time readings of the absolute encoder further includes: The number of cable layers in the winch is determined based on the number of cable turns. The actual cable length is calculated based on the number of cable turns and the number of cable layers. The step of determining the number of cable layers in the winch based on the number of cable turns includes: If the number of cable turns satisfies: in, Let be the number of turns of the i-th layer of cable wound on the winch drum when the cargo lifting device is in its initial position. The first layer is the winch drum. Layer, number The layer is the outermost layer on the winch drum when the cargo lifting device is in its initial position; This determines that the cable in the winch has been lowered to the first position. Layer, in which, The value is pre-stored as a configuration in the computing unit; The step of calculating the actual cable length based on the number of cable turns and the number of cable layers includes: Determine the diameter of the circle containing each layer of cable on the winch drum using the calculation formula: Calculate the actual cable length based on the number of cable loops, the number of cable layers, and the diameter of the circle containing each layer of cable: in, For the first The diameter of the circle containing the layer of cables. Where is the diameter of the winch drum. The diameter of the winch cable. for The actual cable length laid by the winch at any given time. This refers to the total length of the winch cable. For the first The diameter of the circle containing the layer of cables. The length of the cable from the winch drum to the cargo lifting device when the lifting device is in its initial position; wherein, from the first layer to the... The length of the cable in each layer is determined by cumulatively adding up the diameter of the circle containing the cable in each layer; The control method further includes: when the loading of the cargo is detected to be complete, the control unit drives the winch to take up the cable and obtains the reading of the absolute encoder in the winch in real time; when the reading of the absolute encoder is the same as the initial reading, the control unit drives the winch to stop taking up the cable. When the unloading position of the cargo lifting device is not on the wharf plane, the target lifting height of the winch is determined based on the relative height between the unloading position and the wharf plane.

2. The winch lifting height control method for overhead vertical wharves according to claim 1, characterized in that, The control method further includes: Real-time acquisition of winch cable tension; Based on the cable tension, determine whether the loading capacity of the cargo lifting device exceeds the rated carrying capacity; if it does, an alarm will be triggered.

3. The winch lifting height control method for overhead vertical wharves according to claim 2, characterized in that, The step of acquiring the cable tension of the winch in real time includes: Obtain the force value of the pin sensor; calculate the cable tension of the winch based on the force value of the pin sensor: in, Let k be the cable tension. Let k be the force value of the pin sensor at time k. This is the ratio of the force coefficients.

4. A winch lifting height control system suitable for overhead vertical wharves, used to implement the winch lifting height control method for overhead vertical wharves as described in claim 1, characterized in that, The system includes a control unit, a winch, a cargo lifting device, and a computing unit. The winch is located on the wharf plane, and the cargo lifting device is located in a shaft arranged along the height of the wharf. The winch includes a winch body, which includes a motor assembly, a drum, and a frequency converter drive assembly. The motor assembly is connected to the drum via a coupling. The drum includes a first drum with rope grooves, a second drum with rope grooves, a third drum with rope grooves, a fourth drum with rope grooves, a partition, an electromagnetic self-braking safety brake, and an absolute encoder. The winch also includes a cable wound around the drum and connected to the cargo lifting device. The absolute encoder is used to count the number of rotations of the drum. The control unit is used to drive the winch to release and retrieve the cable; The computing unit has a pre-stored configuration. , Let be the number of turns of the i-th layer of cable wound on the winch drum when the cargo lifting device is in its initial position. The layer is the outermost layer on the winch drum when the cargo lifting device is in its initial position; the calculation unit is used to determine the number of cable turns based on the initial and real-time readings of the absolute encoder, and to determine the number of cable layers based on a comparison of the number of cable turns with the configuration. Determine the diameter of the circle containing each layer of cable and accumulate the diameters layer by layer to determine the actual cable length. For the diameter of the winch drum, For the diameter of the winch cable, The control unit drives the winch to stop releasing the cable when the actual cable length reaches the target cable length.

5. The winch lifting height control system for overhead vertical wharves according to claim 4, characterized in that, The control system also includes a pin sensor connected to the cable, which is used to detect whether the load of the cargo lifting device exceeds the rated carrying capacity.

6. The winch lifting height control system for overhead vertical wharves according to claim 4, characterized in that, The motor assembly includes a geared motor, a reducer, an incremental encoder, and an electromagnetic brake; the frequency converter drive assembly includes a frequency converter drive cabinet, which is connected to the geared motor via a cable.

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