WO2018123785A1 - Crane - Google Patents

Abstract

Provided is a crane such that it is possible to prevent the occurrence of a load swinging, due to the stoppage of winch rotation, without a complicated operation when switching winch rotational speed from automatic control to manual operation after lift-off control. This crane 1 comprises a control device 18 for controlling the winch rotational speed to a predetermined speed or less and performing lift-off control where a suspended load W is lifted from the ground, the crane being provided with an accelerator pedal 23 which changes the rate at which the winch rotational speed to approaches a target speed according to the operating position. After the lift-off control is performed by the control device 18 and the suspended load W is lifted from the ground, the accelerator pedal 23 is operated to complete the lift-off control, and control is carried out in such a manner that the winch rotational speed approaches the target speed at the rate corresponding to the operating position.

Description

crane

The present invention relates to a crane. Specifically, the present invention relates to the rotational speed control of a winch after the ground cutting control of the crane.

In recent years, high-strength steel with high strength is used as a material for telescopic booms in cranes, and the telescopic booms are becoming lighter and longer. Increasing the length of the telescopic boom is a factor that increases the amount of bending of the telescopic boom due to the load of the suspended load. When the crane performs a ground cutting for lifting the suspended load from the ground, the tip position is displaced due to the bending of the telescopic boom, so that the swing of the load increases when the amount of bending increases. In view of this, a crane is known in which the telescopic boom is lifted when the ground is cut to correct the displacement of the tip position due to the bending of the telescopic boom to prevent the swinging of the load. For example, as described in Patent Document 1.

The crane described in Patent Document 1 uses a swivel turn, expansion and contraction of a boom (expandable boom), and hoisting and hoisting and lowering operations of the hook together to suspend the required load (suspended load). The tip of the boom is positioned vertically above a hook locked via a tool (such as a wire rope for hanging the ball), and the wire rope and the hanging tool are tensioned so as not to loosen, and each operation is stopped. Next, only the boom is lifted up and the load is cut off. By performing such ground cutting control, the working radius (horizontal distance between the boom hoisting fulcrum shaft and the boom tip) due to the bending of the boom is increased, and the working radius is reduced as the boom hoisting angle is increased. By substantially canceling out the minutes, it is possible to prevent the swinging of the load when the load is cut off.

In the technique described in Patent Document 1, the winch operation lever operates the rotation speed of the winch according to the tilt position in the normal state, but the tilt of the winch operation lever is used as a switch signal during the ground cutting control. The handling ground cutting control is started, and the rotation speed of the winch during the ground cutting control is automatically controlled below a predetermined speed regardless of the tilt position of the winch operation lever. Therefore, when the ground cutting control is completed and the automatic control is switched to the manual operation, if the winch is rotated at a speed corresponding to the tilt position of the winch operation lever, the acceleration is suddenly accelerated from a speed equal to or lower than a predetermined speed. Therefore, in the conventional technique, sudden acceleration is prevented by switching the manual operation to the neutral position where the winch rotation is stopped. However, when switching to manual operation by setting the winch operation lever to the neutral position, the work becomes complicated, and the swing of the winch is generated by stopping the rotation of the winch.

JP 2002-362880 A

An object of the present invention is to provide a crane that can prevent the occurrence of load swing due to the stoppage of winch rotation when the rotation speed of the winch is switched from automatic control to manual operation after ground cutting control. For the purpose of provision.

The problems to be solved by the present invention are as described above. Next, means for solving the problems will be described.

That is, in a crane equipped with a control device that performs ground cutting control for lifting the suspended load from the ground by controlling the rotation speed of the winch to a predetermined speed or less, the rate at which the rotation speed of the winch asymptotically approaches the target speed is set according to the operation position. A winch operation tool to be changed, and after the ground cutting control is performed by the control device and the suspended load is lifted from the ground, when the winch operation tool is operated, the ground cutting control is completed, and the winch Is controlled so as to gradually approach the target speed at a rate corresponding to the operation position.

In a crane provided with a control device that controls a winch to lift a suspended load from the ground by controlling the rotation speed of the winch below a predetermined speed, a winch operation tool that sets a target speed of the winch rotation speed according to an operation position is provided. And the control device performs the ground cutting control and lifts the suspended load from the ground. Then, when the winch operation tool is operated, the ground cutting control is completed, and the rotation speed of the winch is operated. Control is performed so as to approach the target speed according to the position.

A crane including a control device that performs a ground cutting control for controlling a rotation speed of a winch to be equal to or lower than a predetermined speed to lift a suspended load from the ground. The crane includes an accelerator pedal and a winch operation lever, and the ground cutting control is performed by the control device. Then, after lifting the suspended load from the ground, if at least one of the accelerator pedal and the winch operation lever is operated, the ground cutting control is completed, and depending on the operation position of the winch operation lever A winch rotation speed signal that increases according to the depression position of the accelerator pedal, and when the winch operation lever is tilted to one side, the target speed of the winch is set according to the tilt amount. When the winch rotation speed signal is increased at a rate and the winch control lever is tilted to the other side, the tilt The winch rotation speed signal is decreased at a rate according to the amount, the rotation speed of the winch is calculated per unit time based on the winch rotation speed signal increased or decreased by the winch operation lever, and the rotation of the winch The speed is controlled so as to approach the target speed according to the operation position of the winch operation lever.

In the ground cutting control, the crane takes into account the bending of the telescopic boom when the winch is rolled up, and controls the turning of the swivel base, the expansion and contraction and undulation of the telescopic boom, and the operations of hoisting and lowering the winch. Then, the tip of the telescopic boom is disposed vertically above a hook that is locked to the suspended load via a required suspension tool, and the suspended load is lifted from the ground.

The present invention has the following effects.

In a crane, the switching operation from automatic control to manual operation and the acceleration of winch rotation are smooth. As a result, when the rotation speed of the winch is switched from automatic control to manual operation after the ground cutting control, the operation is not complicated, and it is possible to prevent the occurrence of load shake due to the stoppage of the winch rotation.

In a crane, the switching operation from automatic control to manual operation and the setting operation of the target speed of the winch are smooth. As a result, when the rotation speed of the winch is switched from automatic control to manual operation after the ground cutting control, the operation is not complicated, and it is possible to prevent the occurrence of load shake due to the stoppage of the winch rotation.

In a crane, the switching operation from automatic control to manual operation, the acceleration of the winch rotation, and the setting operation of the target speed of the winch are smooth. As a result, when the rotation speed of the winch is switched from automatic control to manual operation after the ground cutting control, the operation is not complicated, and it is possible to prevent the occurrence of load shake due to the stoppage of the winch rotation.

In cranes, switching from automatic control to manual operation is smooth after performing control to prevent load swings during ground cutting. As a result, when the rotation speed of the winch is switched from automatic control to manual operation after the ground cutting control, the operation is not complicated, and it is possible to prevent the occurrence of load shake due to the stoppage of the winch rotation.

The side view showing the whole crane composition concerning one embodiment of the present invention. The figure which shows the structure of the control apparatus of the crane which concerns on one Embodiment of this invention. The figure which shows the graph showing the relationship between the depression position of the accelerator pedal and control amount in control of the crane which concerns on one Embodiment of this invention. (A) The side view which shows the operation state which moves the front-end | tip part of an expansion-contraction boom to the vertically upward direction of the hanging load of the crane which concerns on one Embodiment of this invention, (b) In the hanging load of the crane which concerns on one Embodiment of this invention. The side view which shows the operation state which hangs a main hook block. (A) Side view showing a working state at the time of hoisting in the ground cutting control of the crane according to one embodiment of the present invention, (b) In the ground cutting control of the crane according to one embodiment of the present invention, at the time of rising The side view which shows the working state of. The figure which shows the graph showing the change of the rotational speed of the main winch when the accelerator pedal is stepped on in the asymptotic control of the crane which concerns on one Embodiment of this invention. (A) The figure which shows the graph showing the change of the main winch rotational speed signal when an accelerator pedal is depressed in the asymptotic control of the crane which concerns on one Embodiment of this invention, (b) It concerns on one Embodiment of this invention The figure which shows the graph showing the change of the main winch rotational speed signal when depression of an accelerator pedal is cancelled | released in the middle of control in asymptotic control of a crane. (A) The figure which shows the graph showing the change of the target speed and winch rotation speed signal when a lever is tilted in the direction which increases the rotation speed of a main winch in the asymptotic control of the crane which concerns on one Embodiment of this invention. (B) In the asymptotic control of the crane which concerns on one Embodiment of this invention, the graph showing the change of the target speed and the winch rotational speed signal when a lever is tilted in the direction which reduces the rotational speed of a main winch is shown. Figure. The figure which shows the flowchart showing the control aspect of the ground cutting control and asymptotic control, and the control aspect of the switching in the crane concerning one Embodiment of this invention.

Hereinafter, a crane 1 according to an embodiment of the crane will be described with reference to FIGS. 1 and 2. In the present embodiment, a mobile crane will be described as the crane 1. However, any crane 1 may be used as long as the crane 1 includes the telescopic boom 8, the swivel base 7, and the winch that are raised and lowered by the actuator.

As shown in FIG. 1, the crane 1 is a mobile crane that can move to an unspecified location. The crane 1 has a vehicle 2 and a crane device 6.

The vehicle 2 conveys the crane device 6. The vehicle 2 has a plurality of wheels 3 and travels using an engine (not shown) as a power source. The vehicle 2 is provided with an outrigger 5. The outrigger 5 includes a projecting beam that can be extended by hydraulic pressure on both sides in the width direction of the vehicle 2 and a hydraulic jack cylinder that can extend in a direction perpendicular to the ground. The vehicle 2 can extend the workable range of the crane 1 by extending the outrigger 5 in the width direction of the vehicle 2 and grounding the jack cylinder.

The crane apparatus 6 lifts the suspended load W with a wire rope. The crane device 6 includes a swivel base 7, a telescopic boom 8, a jib 9, a main hook block 10, a sub hook block 11, a hoisting cylinder 12, a main winch 13, a main wire rope 14, a sub winch 15, a sub wire rope 16, and a cabin 17 And a control device 18 (see FIG. 2).

The swivel base 7 is configured to allow the crane device 6 to turn. The swivel base 7 is provided on the frame of the vehicle 2 via an annular bearing. The annular bearing is arranged so that the center of rotation is perpendicular to the installation surface of the vehicle 2. The swivel base 7 is configured to be rotatable in one direction and the other direction with the center of the annular bearing as the center of rotation.

The telescopic boom 8 supports the wire rope so that the suspended load W can be lifted. The telescopic boom 8 is configured to be telescopic in the axial direction by being moved by an unillustrated telescopic cylinder. The telescopic boom 8 is provided on the swivel base 7 so that the base end portion thereof can swing. Accordingly, the telescopic boom 8 is configured to be horizontally rotatable and swingable on the frame of the vehicle 2.

The jib 9 expands the lift and work radius of the crane device 6. The jib 9 is held in a posture along the telescopic boom 8. The jib 9 is configured to be connectable to the distal end portion of the telescopic boom 8.

The main hook block 10 suspends the suspended load W. The main hook block 10 is provided with a plurality of hook sheaves around which the main wire rope 14 is wound and a main hook that suspends the suspended load W. The sub hook block 11 suspends the suspended load W. The sub hook block 11 is provided with a sub hook for hanging the suspended load W.

The raising / lowering cylinder 12 raises and lowers the telescopic boom 8 to hold the posture of the telescopic boom 8. The hoisting cylinder 12 is composed of a hydraulic cylinder composed of a cylinder part and a rod part. In the hoisting cylinder 12, the end of the cylinder portion is slidably connected to the swivel 7, and the end of the rod portion is slidably connected to the telescopic boom 8. The operation of the hoisting cylinder 12 is controlled by a hoisting operation valve 19 (see FIG. 2). The hoisting operation valve 19 is composed of an electromagnetic switching valve that can be switched by moving the spool.

The main winch 13 which is a hydraulic winch is for carrying in (winding up) and feeding out (winding down) the main wire rope 14. The main winch 13 is configured such that a main drum around which the main wire rope 14 is wound is rotated by a main hydraulic motor 20 (see FIG. 2). The main winch 13 feeds out the main wire rope 14 wound around the main drum by supplying hydraulic oil so that the main hydraulic motor 20 rotates in one direction, and the main hydraulic motor 20 moves in the other direction. When the hydraulic oil is supplied so as to rotate, the main wire rope 14 is wound around the main drum and fed.

The sub-winch 15 that is a hydraulic winch is used for feeding and unloading the sub-wire rope 16. The sub winch 15 is configured such that a sub drum around which the sub wire rope 16 is wound is rotated by a sub hydraulic motor. The sub winch 15 feeds out the sub wire rope 16 wound around the sub drum by supplying hydraulic oil so that the sub hydraulic motor rotates in one direction so that the sub hydraulic motor rotates in the other direction. When the hydraulic oil is supplied to the sub-drum, the sub-wire rope 16 is wound around the sub-drum and fed.

The cabin 17 covers the cockpit. The cabin 17 is provided on the side of the telescopic boom 8 in the swivel base 7. A cockpit is provided inside the cabin 17. In the cockpit, a main winch operation lever 22 (see FIG. 2) for operating the main winch 13, a sub winch operation lever for operating the sub winch 15, a hoisting operation tool for operating the telescopic boom 8, A handle for moving the crane 1, a shift lever, an accelerator pedal 23 (see FIG. 2), a brake pedal, a ground cutting control switch 24 (see FIG. 2) for performing ground cutting control, and the like are provided. In the present embodiment, the accelerator pedal 23 is also used for controlling the rotational speed of the main winch 13.

The load detecting means 21 detects a downward load acting on the tip of the telescopic boom 8. The load detecting means 21 is provided on the hoisting cylinder 12.

As shown in FIG. 2, the main winch operation lever 22 which is a winch operation tool sets the target speed of the rotation speed of the main winch 13 and accelerates or decelerates the rotation of the main winch 13 according to the tilt position of the lever. Is. The main winch operation lever 22 is provided with a sensor for detecting the tilt position of the lever.

Accelerator pedal 23, which is a winch operation tool, changes the rotational speed of the engine according to the pedal depression position, thereby accelerating / decelerating the traveling speed of vehicle 2 and accelerating the rotational speed of main winch 13. The accelerator pedal 23 is provided with a sensor that detects the depression position of the pedal. In addition, the accelerator pedal 23 is not limited to what accelerates the rotation speed of the main winch 13, It may accelerate / decelerate.

The crane 1 configured as described above can move the crane device 6 to an arbitrary position by running the vehicle 2. Moreover, the crane 1 raises the telescopic boom 8 to an arbitrary hoisting angle by the hoisting cylinder 12, extends the telescopic boom 8 to an arbitrary telescopic boom 8 length, or connects the jib 9 to the crane device 6. The head and working radius can be expanded.

Hereinafter, the control means of the control device 18 included in the crane 1 will be described with reference to FIG.

The control device 18 performs a ground cutting control for preventing the swinging of the load when the ground is cut and an asymptotic control for controlling the rotation speed of the main winch 13 after the ground cutting control. The control device 18 includes a ground cutting control means 25, a speed asymptotic means 26, a deflection correction control amount calculation means 27, an operation management means 28, and an operation selection means 29. The control device 18 is provided in the vehicle 2.

The earth cutting control means 25 performs control for preventing a load shake at the time of earth cutting.

The speed asymptotic means 26 calculates the rotation speed of the main winch 13 at the time of asymptotic control, and outputs a signal for driving the main winch 13 at the calculated rotation speed.

The bending correction control amount calculation means 27 calculates the rotation speed of the main winch 13 during the ground cutting control, and outputs a signal for driving the main winch 13 at the calculated rotation speed.

The operation management means 28 manages the current control stage. There are three control phases: a normal phase, a ground cutting control phase, and an asymptotic control phase.

The operation selection means 29 selects a signal for driving the main winch 13 according to the control stage. A signal from the main winch operation lever 22 is selected during normal operation, a signal from the deflection correction control amount calculation means 27 is selected during ground cutting control, and a signal from the speed asymptotic means 26 is selected during asymptotic control.

Next, the configuration and signals of the control device 18 will be described with reference to FIGS.

The control device 18 is configured such that a CPU, ROM, RAM, HDD, and the like are connected by a bus as a hardware configuration. Alternatively, the control device 18 may be configured by a one-chip LSI or the like.

The earth cutting control means 25 is connected to the load detection means 21, the hoisting operation valve 19, and the deflection correction control amount calculation means 27.

The speed asymptotic means 26 is connected to the accelerator pedal 23, the main winch operating lever 22, the deflection correction control amount calculating means 27, and the operation selecting means 29.

The bending correction control amount calculation means 27 is connected to the ground cutting control means 25, the speed asymptotic means 26, the operation management means 28, and the operation selection means 29.

The operation management means 28 is connected to the accelerator pedal 23, the main winch operation lever 22, the ground cutting control switch 24, the deflection correction control amount calculation means 27, and the operation selection means 29.

The operation selection means 29 is connected to the main winch operation lever 22, the speed asymptotic means 26, the deflection correction control amount calculation means 27, the operation management means 28, and the main hydraulic motor 20.

The accelerator operation signal Lacc is a signal output according to the depression position of the accelerator pedal 23. The accelerator operation signal Lacc is output from the accelerator pedal 23 to the speed asymptotic means 26 and the operation management means 28.

The main winch operation lever signal Lwin1 is a signal output according to the operation position of the main winch operation lever 22. The main winch operation lever signal Lwin1 is output from the main winch operation lever 22 to the speed asymptotic means 26, the operation management means 28, and the operation selection means 29.

The earth cutting control switch signal SelSw is a signal output when the earth cutting control switch 24 is turned on. The ground cutting control switch signal SelSw is output from the ground cutting control switch 24 to the operation management means 28.

The deflection correction completion signal SigJdg is a signal that is output depending on whether or not the rotational speed of the main winch 13 is being controlled during ground cutting control. The deflection correction completion signal SigJdg is output from the deflection correction control amount calculation unit 27 to the operation management unit 28.

The bending correction control signal Lwin2 is a signal for driving the main winch 13 at the time of ground cutting control at the rotation speed calculated by the bending correction control amount calculation means 27. The deflection correction control signal Lwin2 is calculated by the deflection correction control amount calculation means 27. The deflection correction control signal Lwin2 is output from the deflection correction control amount calculation means 27 to the speed asymptotic means 26 and the operation selection means 29.

The speed asymptotic signal Lwin3 is a signal for driving the main winch 13 at the time of asymptotic control at the rotational speed calculated by the speed asymptotic means 26. The speed asymptotic signal Lwin3 is calculated by the speed asymptotic means 26. The speed asymptotic signal Lwin3 is output from the speed asymptotic means 26 to the operation selecting means 29.

The control stage signal Ctrl is a signal output according to the control stage. The control stage signal Ctrl is output from the operation management unit 28 to the deflection correction control amount calculation unit 27 and the operation selection unit 29. The control stage signal Ctrl is Sel1 (normal stage) during normal operation, Sel2 (ground cutting control stage) during ground cutting control, and Sel3 (asymptotic control stage) during asymptotic control.

The main winch rotation speed signal Lwin is a signal for driving the main winch 13 at a corresponding rotation speed. The main winch rotation speed signal Lwin is output from the operation selection means 29 to the main hydraulic motor 20. The main winch rotation speed signal Lwin is selected when the main winch operation lever signal Lwin1 is selected when the control stage signal Ctrl is Sel1 (normal stage), and when the control stage signal Ctrl is Sel2 (ground cutting control stage). The flexure correction control signal Lwin2 is selected, and when the control stage signal Ctrl is Sel3 (asymptotic control stage), the speed asymptotic signal Lwin3 is selected.

As shown in FIG. 3, the accelerator pedal 23 has a dead zone. The accelerator operation signal Lacc is corrected to the correction signal ΔLt when the dead zone is exceeded, and the correction signal ΔLt is 0 when the dead zone is not exceeded. The correction signal ΔLt is a signal for increasing the rotational speed of the main winch 13 during asymptotic control.

Next, the ground cutting control of the crane 1 will be described with reference to FIGS. 4 and 5.

As shown in FIG. 4 (a), the crane operator visually moves the tip of the telescopic boom 8 vertically above the suspended load W. In addition, the crane operator may move the front-end | tip part of the telescopic boom 8 using a camera etc. not visually.

As shown in FIG. 4B, the slinging operator hangs the suspended load W on the main hook block 10 positioned vertically above the suspended load W. Then, after the slinging operation is completed, the crane operator turns on the ground cutting control switch 24, tilts the main winch operation lever 22, and starts ground cutting control.

As shown in FIG. 5 (a), when the control device 18 winds up the main winch 13 for a unit time, the load of the suspended load W acts on the telescopic boom 8 to cause bending. Move from point A to point B.

As shown in FIG. 5 (b), the control device 18 raises the telescopic boom 8 by the unit lifting amount, so that the tip of the telescopic boom 8 moves from point B to point C. The horizontal movement amount of the distal end portion of the telescopic boom 8 is canceled, and the distal end portion of the telescopic boom 8 moves again vertically above the suspended load W.

Whether or not the suspension of the suspended load W has been completed is determined based on whether or not the detection value detected by the load detection means 21 is constant, and the control device 18 detects that the load detection means 21 detects. The main winch 13 is rolled up (from point A to point B) and raised (from point B to point C) until the value becomes constant.

As a result, when the detection value detected by the load detection means 21 becomes constant, the suspended load W is grounded without shaking. In addition, although the case where the vertical deflection | deviation produced was demonstrated, it is not limited to this, If the lateral deflection | deviation has arisen, the expansion-contraction boom 8 can also be swung and it can be moved just above the suspended load W. That is, in the ground cutting control, the crane 1 controls the swinging of the swivel base 7, the expansion and contraction and undulation of the telescopic boom 8, and the hoisting and unwinding operations of the main winch 13, and the necessary suspension of the suspended load W is performed. The suspended load W is lifted from the ground in a state where the distal end portion of the telescopic boom 8 is disposed vertically above the hook locked through the tool.

Next, asymptotic control of the crane 1 will be described with reference to FIG. It is assumed that at the time of the ground cutting control before the asymptotic control, the crane operator turns on the ground cutting control switch 24 and tilts the main winch operation lever 22.

As shown in FIG. 6, the target speed of asymptotic control is set according to the position where the crane operator tilts the main winch operation lever 22 at the start of ground cutting control. If the accelerator pedal 23 is depressed to the depressing position x1 at time t0 in a state where the main winch 13 is controlled to a predetermined speed or less and the suspended load W is lifted after the ground cutting is completed, the control stage is the ground cutting. Switch from the control stage to the asymptotic control stage. Thereafter, the rotational speed of the main winch 13 gradually approaches the target speed according to the depression position of the accelerator pedal 23, and reaches the target speed at time t1. The switching from the ground cutting control to the asymptotic control is not limited to the operation of the accelerator pedal 23, and is switched by operating at least one of the accelerator pedal 23 and the main winch operation lever 22. Further, acceleration and deceleration of the rotation speed of the main winch 13 are also operated by the main winch operation lever 22.

The rotational speed of the main winch 13 during asymptotic control is calculated for each unit time based on the following equation (1). A speed asymptotic signal based on a time t when the start time of asymptotic control is 0, a main winch operation lever signal Lwin1, a deflection correction control signal Lwin2, and a signal obtained by integrating the correction signal ΔLt from time 0 to time t. Lwin3 is calculated. However, in order to set the main winch operation lever signal Lwin1 as the target speed, when the speed asymptotic signal Lwin3 becomes equal to or higher than the main winch operation lever signal Lwin1, the control device 18 completes the ground cutting control and sets the control stage to the ground cutting control stage. Change from normal to normal.

Equation 1 includes a first factor 201, a second factor 202, a third factor 203, and a function min.

The first factor 201 is a factor that increases as the accelerator pedal 23 is depressed. The first factor 201 is the ratio of the sum of the deflection correction control signal Lwin2 at the start of asymptotic control and the signal obtained by integrating the correction signal ΔLt from time 0 to time t with respect to the main winch operation lever signal Lwin1 at the start of asymptotic control. Yes, the minimum value of the ratio and 1 is selected by the function min.

The second factor 202 is a factor that increases or decreases in accordance with the operation of the main winch operation lever 22. The second factor 202 is a ratio of the main winch operation lever signal Lwin1 at time t to the main winch operation lever signal Lwin1 at the start of asymptotic control.

The third factor 203 is the main winch operation lever signal Lwin1 at time t.

As the velocity asymptotic signal Lwin3, the minimum value of the product of the first factor 201, the second factor 202, and the third factor 203 and 1 is selected by the function min.

Next, the relationship between the number 1 of the crane 1 and the operation of the accelerator pedal 23 and the main winch operation lever 22 will be described.

As shown in Equation 2, since the elapsed time is zero when the control stage is switched from the ground cutting control to the asymptotic control, the signal obtained by integrating the correction signal ΔLt from time 0 to time t becomes zero, and the speed asymptotic signal Lwin3 becomes Lwin2 (0). That is, at the start of asymptotic control, the rotational speed of the main winch 13 is the same as the rotational speed at the completion of the ground cutting control.

As shown in Equation 1, when the accelerator pedal 23 is depressed beyond the dead zone, the first factor 201 is calculated according to the depression position of the accelerator padal 23. The first factor 201 increases the signal obtained by integrating the correction signal ΔLt from time 0 to time t, and increases from Lwin2 (0) / Lwin1 (0) with 1 as the upper limit. As a result, the rotation speed of the main winch 13 gradually approaches the product of the second factor 202 and the third factor 203. However, when the speed asymptotic signal Lwin3 becomes equal to or higher than the main winch operation lever signal Lwin1, the control device 18 completes the ground cutting control, changes the control stage from the ground cutting control stage to the normal stage, and rotates the main winch 13 The speed is set to a rotational speed corresponding to the main winch operation lever signal Lwin1.

When the main winch operation lever 22 is tilted in one direction (in the direction in which the rotation speed of the main winch 13 increases), the second factor 202 is that the main winch operation lever signal Lwin1 increases and 1 to Lwin1 (t) / Lwin1 ( 0). The third factor 203 increases from Lwin1 (0) to Lwin (t). As a result, the speed asymptotic signal Lwin3 increases at a rate corresponding to the tilt amount of the main winch operation lever 22, and the main winch rotation speed signal Lwin for driving the main winch 13 also increases.

When the main winch operation lever 22 is tilted in the other direction (the direction in which the rotation speed of the main winch 13 decreases), the second factor 202 is that the main winch operation lever signal Lwin1 decreases and 1 to Lwin1 (t) / Lwin1 ( 0). The third factor 203 decreases from Lwin1 (0) to Lwin (t). As a result, the speed asymptotic signal Lwin3 decreases at a rate corresponding to the tilt amount of the main winch operation lever 22, and the main winch rotation speed signal Lwin for driving the main winch 13 also decreases.

Next, the control of the rotation speed of the main winch 13 according to the operation of the accelerator pedal 23 of the crane 1 will be described with reference to FIGS.

As shown in FIG. 2, when the ground cutting control switch 24 is turned ON, the ground cutting control switch signal SelSw is output to the operation management means 28. At this time, when the main winch operation lever 22 is tilted, the main winch operation lever signal Lwin1 is output to the operation management means 28 and the speed asymptotic means 26. The operation management means 28 changes the control stage signal Ctrl from Sel1 (normal stage) to Sel2 (ground cutting control stage) and outputs it to the operation selection means 29. The speed asymptotic means 26 sets the main winch operation lever signal Lwin1 as a target speed signal for asymptotic control. The bend correction control amount calculation unit 27 calculates the bend correction control signal Lwin2 and outputs it to the operation selection unit 29. The operation selection means 29 outputs the deflection correction control signal Lwin2 to the main hydraulic motor 20 as the main winch rotation speed signal Lwin.

At the time of the earth cutting control, the earth cutting control means 25 determines that the earth cutting is completed based on the detection value detected by the load detection means 21 and determines that the earth cutting has been completed when the detection value is constant after the increase. After a predetermined time has elapsed, the deflection correction control amount calculation means 27 outputs the deflection correction completion signal SigJdg to the operation management means 28 as TRUE.

As shown in FIG. 7A, when the accelerator pedal 23 is depressed and the depression position is changed from 0 to x2 at the time t0 when the ground cutting is completed and the main winch 13 is rotating at a predetermined speed or less. The accelerator pedal 23 outputs an accelerator operation signal Lacc to the operation management means 28 and the speed asymptotic means 26 (see FIG. 2). The operation management means 28 changes the control stage signal Ctrl from Sel2 (ground cutting control stage) to Sel3 (asymptotic control stage), and outputs it to the operation selection means 29 (see FIG. 2). The speed asymptotic means 26 calculates a speed asymptotic signal Lwin3 based on the equation 1 and outputs it to the operation selection means 29. The operation selection means 29 outputs the speed asymptotic signal Lwin3 as the main winch rotation speed signal Lwin to the main hydraulic motor 20 (see FIG. 2).

When the speed asymptotic signal Lwin3 is asymptotic to the main winch operation lever signal Lwin1 and the speed asymptotic signal Lwin3 becomes equal to or greater than the main winch operation lever signal Lwin1 at time t2, the operation management means 28 sets the control stage signal Ctrl to Sel3 ( Change from asymptotic control stage) to Sel1 (normal stage).

As shown in FIG. 7B, when the depression of the accelerator pedal 23 is released from the time t2 to the time t3, the increase of the first factor 201 of Formula 1 is stopped between the time t2 and the time t3. . Therefore, the speed asymptotic signal Lwin3 calculated by the speed asymptotic means 26 (see FIG. 2) becomes constant, and the rotation speed of the main winch 13 is maintained. When the accelerator pedal 23 is depressed again at time t3, the first factor 201 of Formula 1 increases and the rotation speed of the main winch 13 increases. Since the time other than the period from time t2 to time t3 is the same as when no depression is released, detailed description is omitted.

Next, the control of the rotation speed of the main winch 13 according to the operation of the main winch operation lever 22 of the crane 1 will be described with reference to FIGS.

As shown in FIG. 8A, when the main winch operation lever 22 is tilted from y1 to y2 in the direction of increasing the rotation speed of the main winch 13 during the time t3 to t5, the main winch operation lever 22 The winch operation lever signal Lwin1 is output to the speed asymptotic means 26 and the operation management means 28 (see FIG. 2). The speed asymptotic means 26 increases the target speed signal from Lc to Ld, calculates the speed asymptotic signal Lwin3 based on Equation 1, increases it from Lb to Le, and outputs it to the operation selection means 29. The operation selection means 29 outputs the speed asymptotic signal Lwin3 as the main winch rotation speed signal Lwin to the main hydraulic motor 20 (see FIG. 2). Since the time before the time t3 is the same as the time t3 in FIG. 7B described above, a detailed description thereof will be omitted.

As shown in FIG. 8B, when the main winch operation lever 22 is tilted from y1 to y3 in the direction of decreasing the rotation speed of the main winch 13 during the time t3 to t5, the main winch operation lever 22 The winch operation lever signal Lwin1 is output to the speed asymptotic means 26 and the operation management means 28 (see FIG. 2). The speed asymptotic means 26 decreases the target speed signal from Lc to Lf, calculates the speed asymptotic signal Lwin3 based on Equation 1, decreases it from Lb to Lg, and outputs the speed asymptotic signal Lwin3 to the operation selection means 29. The operation selection means 29 outputs the speed asymptotic signal Lwin3 as the main winch rotation speed signal Lwin to the main hydraulic motor 20 (see FIG. 2). Since the time before the time t3 is the same as the time t3 in FIG. 7B described above, a detailed description thereof will be omitted.

Next, with reference to FIG. 9, the control mode of the ground cutting control and asymptotic control and the control mode of the switching will be specifically described in the control device 18 of the crane 1. In the present embodiment, it is assumed that the ground cutting control switch 24 is ON.

In step S100, the control device 18 determines whether or not the main winch operation lever 22 is tilted.
As a result, when it is determined that the main winch operation lever 22 is tilted, the control device 18 shifts the step to step S110.
On the other hand, when it is determined that the main winch operation lever 22 is not tilted, the control device 18 shifts the step to step S100.

In step S110, the control device 18 changes the control stage signal from Sel1 (normal stage) to Sel2 (ground cutting control stage), and shifts the step to step S120.

In step S120, the control device 18 executes ground cutting control, and the step proceeds to step S130.

In step S130, the control device 18 determines whether or not the detection value detected by the load detection means 21 is constant after the increase, that is, whether or not the ground cutting is completed.
As a result, when it is determined that the detection value detected by the load detection means 21 is constant after the increase, that is, the ground cutting is completed, the control device 18 shifts the step to step S140.
On the other hand, when it is determined that the detected value detected by the load detecting means 21 is not constant after the increase, that is, the ground cutting is not completed, the control device 18 shifts the step to step S130.

In step S140, the control device 18 determines whether or not a predetermined time has elapsed since the earth cutting was completed.
As a result, when it is determined that the predetermined time has elapsed since the earth cutting is completed, the control device 18 shifts the step to step S150.
On the other hand, when it is determined that the predetermined time has not elapsed since the earth cutting is completed, the control device 18 shifts the step to step S140.

In step S150, the control device 18 sets the deflection correction completion signal SigJdg to TRUE, and proceeds to step S200.

In step S200, the control device 18 determines whether or not at least one of the accelerator pedal 23 and the main winch operation lever 22 has been operated.
As a result, when it is determined that at least one of the accelerator pedal 23 and the main winch operation lever 22 is operated, the control device 18 shifts the step to step S210.
On the other hand, when it is determined that at least one of the accelerator pedal 23 and the main winch operation lever 22 is not operated, the control device 18 shifts the step to step S200.

In step S210, the control device 18 changes the control stage signal from Sel2 (ground cutting control stage) to Sel3 (asymptotic control stage), and shifts the step to step S220.

In step S220, the control device 18 acquires the accelerator operation signal Lacc from the accelerator pedal 23, acquires the main winch operation lever signal Lwin1 from the main winch operation lever 22, and shifts the step to step 230.

In step S230, the control device 18 calculates the speed asymptotic signal Lwin3 based on Equation 1, and outputs it to the main hydraulic motor 20 as the main winch rotation speed signal Lwin, and the process proceeds to step S240.

In step S240, control device 18 determines whether or not speed asymptotic signal Lwin3 is equal to or greater than main winch operation lever signal Lwin1.
As a result, when it is determined that the speed asymptotic signal Lwin3 is greater than or equal to the main winch operation lever signal Lwin1, the control device 18 shifts the step to step S250.
On the other hand, when it is determined that the speed asymptotic signal Lwin3 is not greater than or equal to the main winch operation lever signal Lwin1, the control device 18 shifts the step to step S220.

In step S250, the control device 18 changes the control stage signal from Sel3 (ground cutting control stage) to Sel1 (normal) and ends the process.

This configuration allows the crane 1 to switch from automatic control to manual operation after performing ground cutting control without delay. As a result, when the rotation speed of the main winch 13 is switched from automatic control to manual operation after the ground cutting control, the operation is simplified, and the occurrence of load shake due to the stop of the rotation of the main winch 13 can be prevented.

In the above-described ground cutting control and asymptotic control, the suspended load W is grounded and wound up using the main winch 13, but the suspended load W may be transported using the sub winch 15. Further, although the accelerator pedal 23 and the main winch operation lever 22 are used as the winch operation tool, the rotational speed of the main winch 13 may be controlled only by the accelerator pedal 23.

The above-described embodiments are merely representative, and various modifications can be made without departing from the scope of one embodiment. It goes without saying that the present invention can be embodied in various forms, and the scope of the present invention is indicated by the description of the scope of claims, and the equivalent meanings of the scope of claims, and all the scopes within the scope of the claims Includes changes.

The present invention can be used for a crane.

DESCRIPTION OF SYMBOLS 1 Crane 8 Telescopic boom 19 Control apparatus 23 Accelerator pedal W Suspended load

Claims (4)

In a crane equipped with a control device for controlling the turning of the winch to control the rotation speed of the winch below a predetermined speed to lift the suspended load from the ground,
A winch operation tool for changing a ratio of gradually increasing the rotation speed of the winch to a target speed according to an operation position,
After carrying out the ground cutting control by the control device and lifting the suspended load from the ground,
A crane that, when the winch operating tool is operated, completes the ground cutting control and controls the rotational speed of the winch to gradually approach the target speed at a rate corresponding to the operation position. In a crane equipped with a control device for controlling the turning of the winch to control the rotation speed of the winch below a predetermined speed to lift the suspended load from the ground,
A winch operation tool for setting a target speed of the rotation speed of the winch according to the operation position,
After carrying out the ground cutting control by the control device and lifting the suspended load from the ground,
A crane that, when the winch operation tool is operated, completes the ground cutting control and controls the rotation speed of the winch to gradually approach the target speed corresponding to the operation position. In a crane equipped with a control device for controlling the turning of the winch to control the rotation speed of the winch below a predetermined speed to lift the suspended load from the ground,
An accelerator pedal,
A winch operating lever,
After carrying out the ground cutting control by the control device and lifting the suspended load from the ground,
When at least one of the accelerator pedal and the winch operation lever is operated, the ground cutting control is completed,
While setting the target speed of the rotation speed of the winch according to the operation position of the winch operation lever,
A winch rotation speed signal that increases to the depression position of the accelerator pedal is calculated,
When the winch operation lever is tilted to one side, the winch rotation speed signal is increased at a rate corresponding to the tilt amount,
When the winch operation lever is tilted to the other side, the winch rotation speed signal is decreased at a rate corresponding to the tilt amount,
Based on the winch rotation speed signal increased or decreased by the winch operation lever, the rotation speed of the winch is calculated per unit time, and the rotation speed of the winch is the target speed corresponding to the operation position of the winch operation lever. Crane to control asymptotically. In the ground cutting control, according to the deflection of the telescopic boom at the time of winding the winch,
Control each of the swivel turn, expansion and contraction and undulation of the telescopic boom, and winding and unwinding of the winch,
The front-end | tip part of the said expansion-contraction boom is arrange | positioned vertically above the hook latched to the said suspended load via the required lifting tool, The said suspended load is lifted from the ground. Crane.

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