Patent Grant
11970376
The present disclosure relates to winches on machines and, more particularly, to systems and methods for maintaining a desired line speed generated by a winch.
Winches are used to perform a variety of tasks and therefore are used in a variety of machines. For example, machines such as bulldozers have evolved to include winches to perform tasks in addition to those related to their original earth-moving design. Other machines, such as pipelayers, are designed to use a winch as the primary tool to accomplish work tasks. These tasks often require the winch cable to be reeled in or reeled out in a controlled manner to permit an operator to perform a desired task.
Mechanical winch assemblies are often difficult or challenging to control because the rate of cable pull or line/hook speed is influenced by the number of layers of cable or rope on the drum. It will be appreciated, for example, that as more layers of cable are reeved onto a winch drum, at a given rotational speed of the drum, the line speed of cable retrieved onto the drum increases because the effective combined diameter of the drum and cable increases. The change in line speed from a first number of layers of cable to a second number of layers of cable changes as a function of the diameter of the cable and, in addition, the arrangement of the cable layers stacked on the winch drum.
In particular, some tasks require careful control of the line speed of the winch rope or cable which is complicated by the change of diameter of the coil of rope on the winch drum as the rope is reeved onto or off of a winch drum. It is therefore necessary for the operator of the winch to manually regulate the speed input command to the winch. Depending on the experience of the operator, it can be a challenge to operate the machine and the winch so as to successfully complete a task being performed.
Chinese Patent No. 103395712(B) discusses an output-characteristic-adjustable hydraulic capstan electrohydraulic control system wherein the linear speed of the winch rope is increased or decreased to fall under a pre-determined range to compensate the change in the diameter of the coil by keeping the pulling force constant. It is believed that the measurement of pulling force does not necessarily correspond to reliable regulation of winch line speed.
There is a demand for reliable systems and methods for compensating for changes in line speed due to the number of layers of rope on a winch drum. The present disclosure addresses the demand.
The foregoing background discussion is intended solely to aid the reader. It is not intended to limit the innovations described herein, nor to limit or expand the prior art discussed. Thus, the foregoing discussion should not be taken to indicate that any particular element of a prior system is unsuitable for use with the innovations described herein, nor is it intended to indicate that any element is essential in implementing the innovations described herein. The implementations and application of the innovations described herein are defined by the appended claims.
In one aspect, the disclosure includes a system for controlling a winch assembly including a rotatable winch drum with an attached cable. A winch motor is configured to rotate the winch drum. A sensor is configured to generate signals indicative of the number of layers of the winch cable on the winch drum. A winch controller is configured to receive a control input requesting a selected rotation of the winch drum, receive the signals from the sensor, determine a number of layers of the winch cable disposed on the winch drum, and generate at least one control command to control the winch motor to rotate the winch drum based on the control input and the number of layers of the winch cable. The control command rotates the winch drum to produce a substantially constant line speed based on the selected control input independent of the number of layers determined to be disposed on the winch drum.
In another aspect, the disclosure includes a machine that includes a machine chassis and a winch system including a winch drum configured to rotate, a winch motor configured to rotate the winch drum, a winch cable attached to the winch drum, a sensor configured to generate signals indicative of the number of layers of the winch cable on the winch drum, and a hook attached to the winch cable for coupling to a load. A control system includes a controller configured to receive the signals from the sensor, determine the number of layers of the winch cable that are disposed on the winch drum based on said signals, and generate at least one control command to control the winch motor. The winch drum is thereby rotated based on at least the determination of the number of layers of the winch cable, wherein the at least one control command causes the winch drum to rotate to produce a substantially constant line speed independent of the number of layers determined to be disposed on the winch drum.
Yet another aspect of the disclosure includes a method of operating a winch system of a machine. The method includes receiving, with a controller, a control input; receiving, with the controller, signals indicative of a number of layers of cable on a winch drum of a winch of the winch system; determining, with the controller, the number of layers of cable on the drum based on receiving of the signals; generating at least one control command based on at least the receiving of the control input and the determining of the number of layers; and rotating the drum based on the at least one control command so as to produce a substantially constant line speed independent of the number of layers determined to be disposed on the winch drum.
Now referring to the drawings, wherein like elements refer to like reference numbers, there is illustrated in
The pipelayer 10 includes a work machine chassis 11 including a first side 11a and a second side 11b. The chassis 11 may be a standard pipelayer chassis 11. A first sub-frame, for example a counterweight frame 12, is attached to the first side 11a of the chassis 11, and a second sub frame, for example a boom frame 13, is attached to a second side 11b of the chassis 11. A conventional boom assembly 15 of the type known in the art is attached to the boom frame 13, and a counterweight 18 and a winch assembly 14 of the type known in the art is attached to the counterweight frame 12.
The winch assembly 14 may include a boom winch 16, and a load winch 17. The boom winch 16 is coupled to a boom block 19 of a boom 20 via a boom cable 21 such that rotation of the boom winch 16 in one direction causes the boom 20 to lower and rotation in the other direction causes the boom 20 to raise. Similarly, the load winch 17 is coupled to a load hook block and hook assembly 22 via a load cable 23 that is routed around a load sheave 24 such that the rotation of the load winch 17 in one direction causes the load hook block and load hook to lower and rotation in the other direction causes the load hook block to be raised. For purposes of this disclosure, the terms rope and cable will be used interchangeably. Thus, the boom and load winches 16 and 17 are used to lift, position and lower a load, such as a pipe, attached to the load hook of the load hook block and hook assembly 22. Other configurations and numbers of elements related to the boom winch 16 and/or load winch 17 are contemplated. It should also be appreciated that the counterweight 18 is movable to compensate for the position of the boom and the load on the boom 20. A bumper 41 of the type known in the art used specifically for pipelayers is attached to a front of the chassis 11.
The machine 10 includes a cab 34 (for clarity, only a portion of cab 34 is shown in
The machine 10, referring also to
The winch system 40 may include a winch motor 42 that is electrically connected to the inverter 27. The winch motor 42 may have any desired configuration. In embodiments, the winch motor 42 may be a switched reluctance motor that operates with AC power. In operation, DC power may be supplied by the inverter 27 through an electrical cable or cable assembly 43 to a second or “half” inverter 44 that converts the DC power to AC power. The AC power is then supplied through cable assembly 45 to drive the winch motor 42. In other embodiments, the inverter 27 may be configured to supply AC power to the winch motor 42 without the half inverter 44. In still other embodiments, the winch motor 42 may be a DC motor and DC power may be supplied by the inverter 27 or through another source on the machine without the half inverter 44. In yet other embodiments, the winch motor 42 is hydraulic or electrohydraulic. While an electrical system is given as an example of one means for operating the winches disclosed herein, it will be understood that hydraulically actuated winches are more typically employed in the operation of pipelayers, as well as other machines designed for use in construction and other settings.
A rotatable winch drum 47 of load winch 17 may be operatively connected to the winch motor 42 by a gear system 46 that is operatively connected to the motor. In embodiments, the gear system 46 may be configured to provide a plurality of rotations of the winch motor 42 for each rotation of the winch drum 47. Rotation of the winch drum 47 may be arrested or prevented by a brake system 48 operatively connected thereto. The gear system 46 and the brake system 48 may have any desired configuration. In embodiments, the gear system 46 and the brake system 48 may be configured with a default condition in which rotation of the winch drum 47 is prevented (i.e., whereby the brake is applied) unless the brake system is disengaged. The winch drum 47 may be configured with the winch load cable 23 wrapped around it a plurality of times. The number of times that the winch cable 23 is wrapped around the winch drum 47 is a function of the size of the drum as well as the length and diameter of the winch cable. Other configurations of the winch system 40 are contemplated.
The operation of the engine 25, winch system 40, and other systems and components of the machine 10 are controlled by a winch control system 52 as shown generally in
The winch controller 51 (
The winch controller 51 may be a single controller or may include more than one controller disposed to control various functions and/or features of the machine 10. The term “controller” is meant to be used in its broadest sense to include one or more controllers and/or microprocessors that may be associated with the machine 10 and that may cooperate in controlling various functions and operations of the machine. The functionality of the winch controller 51 may be implemented in hardware and/or software without regard to the functionality. The winch controller 51 may rely on one or more data maps relating to the operating conditions and the operating environment of the machine that may be stored in the memory of controller. Each of these data maps may include a collection of data in the form of tables, graphs, and/or equations.
The control system 52 and the winch controller 51 may be physically located on the machine 10 and may also include components located remotely from the machine. The functionality of control system 52 may be distributed so that certain functions are performed at machine 10 and other functions are performed remotely.
Referring to
A voltage sensor 55 may be provided to sense the voltage at the winch motor 42 and provide voltage data indicative of the voltage. In an embodiment, the voltage sensor 55 may be part of or within the half inverter 44 and have any desired configuration. If the winch system 40 does not include the half inverter 44, the voltage sensor 55 may be part of or within the inverter 27. Other locations for the voltage sensor and other configurations of voltage sensors are contemplated.
A current sensor 56 may be provided to sense the current provided to the winch motor 42 and provide current data indicative of the current. In an embodiment, the current sensor 56 may be part of or within the half inverter 44 and have any desired configuration. If the winch system 40 does not include the half inverter 44, the current sensor may be part of or within the inverter 27. Other locations for the current sensor and other configurations of current sensors are contemplated.
Inasmuch as the torque provided by the winch motor 42 is a function of the voltage at which the motor is operating and the current provided to the motor, the voltage sensor 55 and the current sensor 56 may define a torque sensor. Accordingly, if the torque provided by the winch motor 42 in a different manner, the necessary current may be determined based upon the torque and the voltage.
A drum sensor 57 may be provided for sensing, directly or indirectly, the rotational position of the winch drum 47 and for providing rotation data indicative of the rotational position. The drum sensor 57 may have any desired configuration such as a rotary encoder mounted on or adjacent either the winch motor 42 or the winch drum 47, a camera for collecting visual information indicating the number of layers of winch cable on the drum, or any suitable device or system that is configured to acquire information indicative of the number of layers of winch cable on the drum and convey that information to the winch controller 51, including radar, LIDAR, and acoustic sensors.
In some instances, it may be desirable to monitor the position of the winch motor 42 rather than the winch drum 47 since the winch system 40 may be configured such that the winch motor rotates a number of times that is unequal to the rotation of the winch drum. The winch controller 51 may monitor, store, and convey rotational data of the winch motor 42 (or winch drum 47) to determine changes in the angular position and the number of rotations of the winch drum 47.
In addition to operating as a rotation position sensor, the drum sensor 57 may also be configured to operate as a rotation identification system that senses whether the winch motor 42, and thus the winch drum 47, is rotating or is stationary. In other embodiments, a separate rotation identification sensor may be provided to determine whether the winch motor 42 and/or the winch drum 47 are rotating.
In embodiments, the drum sensor 57, when configured to sense rotation of the winch drum 47, may be used to generate signals, that when analyzed by the winch controller 51, are indicative of how many rotations the winch drum has rotated and/or how many layers of cable 23 are positioned on the drum. For example, a predetermined number of rotations of the winch drum 47 may be interpreted by the winch controller 51 as a change of the numbers of layers of cable 23 on the drum 47 equal to one layer. For example, when the numbers of layers of cable 23 on the drum 47 is indicated or determined to be zero, a change of thirteen rotations pulling cable onto the drum adds one layer of cable. A further change of 12 rotations adds a second layer of cable, and so on. The winch controller 51 therefore determines the number of layers of cable 23 on the drum 47 based on a count of rotations. When cable 23 is released off of the drum 47, and signals are generated indicating a predetermined number of rotations of the drum, one layer of cable is subtracted from the previously determined number of layers. Responsive to a determination that the number of layers of cable 23 is changed from a previously determined number, the winch controller 51 is programmed to change the control command to the winch motor 42 an amount to maintain a constant or substantially constant line speed of cable 23 as long as the operator input remains unchanged. For the present disclosure, “substantially” will be used to mean within about 10 percent of the relevant target value.
Further aspects of the control system 52 include an input for receiving signal related to the selection of an operational mode 62, which may be in the form of a direction control input or direction request, to reel in or out cable 23 or operation of the boom winch 16 to raise or lower the boom assembly 15. Also, the control system 52 includes an input for receiving signals for manually adjusting the load 66 of the load winch, which may be a speed control input or speed request via the joystick 35 (
One example of the change in line speed of the load cable 23 at the hook assembly 22 as a function of the effective diameter (the combined diameter of the drum and cable) is shown below in Table 1 below. The values are based on a drum diameter of 266.7 millimeters (mm) and a cable diameter of 19 mm and assumes that the drum 47 is turned at 60 revolutions per minute (RPM). It should be noted that the cable does not stack in layers equal to the cable diameter (19 mm) because the cable may assume a nested configuration, an example of which is shown in
In one example, given a cable 23 that is 19 mm in diameter laid up as shown in
For example, the line speed in the above exemplary table with an effective diameter of 285.7 millimeters (mm), i.e., with one (1) layer of cable on the drum is 6.7 meters per minute (m/min) at the hook assembly, or of the hook itself. When cable is being wound onto the drum and two (2) layers of cable are positioned on the drum, the effective diameter increases to 319.9 mm. As a result, given a constant drum RPM and constant control input from the operator, the speed would increase to 7.5 m/min of the hook assembly. This is because the line speed, wherever it is measured, is a function of the effective diameter.
The increase in effective diameter from one layer at 285.7 mm to two layers at 319.9 mm and the resulting increase in line speed from 6.7 m/min to 7.5 m/min is an increase of about 11.9 percent. To maintain a constant line speed therefore, the drum 47 is controlled, by output control commands 71 generated by the winch controller 51 and sent to the winch motor 42 (or an equivalent winch rotating mechanism) to turn at a lesser rotational speed (about 11.9 percent in this example) such that the line speed is 6.7 m/min at the hook assembly with two layers of cable wound onto the drum 47. A calculation is made by the winch controller 51 and a control command 71 is generated by the winch controller based on a determination of the numbers of layers of cable on the drum in the same manner as illustrated above with respect to a change of one cable layer to two cable layers and in view of the input direction of line/hook movement. Therefore, when the winch controller 51 can determine the number of layers of cable on the winch drum, a calculation can be made to adjust the control command 71 and therefore the rotational speed of the winch drum to maintain a constant line speed, assuming a given, fixed input command from the operator.
The relationship may be represented by the following equation, which may be resident in and used by the controller 51 to perform a calculation to determine the amount of correction to be made of the control command required to produce the desired, requested line speed:
Where S is winch line speed (m/min);
N is winch input speed;
d is rope diameter;
K is rope compensation factor (range is typically 0.7-0.9);
n is rope layer;
D is drum diameter (mm); and
R is winch reduction value.
It will be understood that inputs may be provided for an operator or the like to enter values into the controller as needed to perform the calculation. Alternatively, the values may be predetermined based on a specified configuration of machine and rope and therefore fixed and provided to and stored within the controller to be used in calculating the correction required.
The industrial applicability of the system described herein will be readily appreciated from the forgoing discussion. The foregoing discussion is applicable to machines that employ winches in either a main functionality of the machine or as an auxiliary functionality of the machine. In yet other examples, the present disclosure may be applied to operations employing a winch or winches that benefit from an accurately controlled lifting or lowering task or tasks, even when the task is being conducted by a relatively inexperienced operator.
One example of the industrial applicability according to the disclosure includes a method of operating a machine 10 with a winch system 40 is shown in
If the cable 23 is changed in diameter, a control map is selected in step 102 and employed by the winch controller 51 that uses different variables relating to the diameter of the winch drum 47, a selected diameter of cable 23, and a predetermined change in diameter based on number of cable layers. Once a map has been confirmed or selected and loaded into the winch controller 51, the winch controller is configured to receive input signals from the operator relating to a line speed request and a line direction request in step 106. The winch controller 51 is configured to receive signals from a drum sensor 57 indicative of the number of layers of cable on the drum 47 in step 108. In step 110, control commands 71 are generated using the selected control map based on control inputs from step 106 and the detected layer from 108 to adjust the rotational speed of the drum 47 to maintain a constant line speed when the speed control input from the operator is unchanged. It will be appreciated that in embodiments, the controller 51 may be provided with or will have access to control maps that correspond to a cable diameter designed for or originally specified for the machine 10 and maps that correspond to cables with diameters that are different.
It will be appreciated that the foregoing description provides examples of the disclosed system and technique. However, it is contemplated that other implementations of the disclosure may differ in detail from the foregoing examples. All references to the disclosure or examples thereof are intended to reference the particular example being discussed at that point and are not intended to imply any limitation as to the scope of the disclosure more generally. All language of distinction and disparagement with respect to certain features is intended to indicate a lack of preference for those features, but not to exclude such from the scope of the disclosure entirely unless otherwise indicated.
Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context.
Unless explicitly excluded, the use of the singular to describe a component, structure, or operation does not exclude the use of plural such components, structures, or operations or their equivalents. The use of the terms “a” and “an” and “the” and “at least one” or the term “one or more,” and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The use of the term “at least one” followed by a list of one or more items (for example, “at least one of A and B” or one or more of A and B″) is to be construed to mean one item selected from the listed items (A or B) or any combination of two or more of the listed items (A and B; A, A and B; A, B and B), unless otherwise indicated herein or clearly contradicted by context. Similarly, as used herein, the word “or” refers to any possible permutation of a set of items. For example, the phrase “A, B, or C” refers to at least one of A, B, C, or any combination thereof, such as any of: A; B; C; A and B; A and C; B and C; A, B, and C; or multiple of any item such as A and A; B, B, and C; A, A, B, C, and C; etc.
Accordingly, this disclosure includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the disclosure unless otherwise indicated herein or otherwise clearly contradicted by context.
| Number | Name | Date | Kind |
|---|---|---|---|
| 20050072965 | Sanders | Apr 2005 | A1 |
| 20160096709 | Averill | Apr 2016 | A1 |
| 20160318740 | Kos | Nov 2016 | A1 |
| 20200189890 | Kieser et al. | Jun 2020 | A1 |
| Number | Date | Country |
|---|---|---|
| 203382434 | Jan 2014 | CN |
| 204057820 | Dec 2014 | CN |
| 103395712 | Feb 2016 | CN |
| 108116623 | Aug 2019 | CN |
| 891145 | Mar 1962 | GB |
| Number | Date | Country | |
|---|---|---|---|
| 20230101055 A1 | Mar 2023 | US |
