Crane control method and crane

Abstract

To simplify operation of a crane before or after work.SOLUTION: When first start operation is being performed under the situation where a start mode is set, a control device 6 executes boom standing control (S201 to S209). When second start operation is being performed, the control device 6 executes jib shake-out control. The boom standing control includes control by the control device 6 to make a second winch execute operation of winding a second rope if a detection value of a jib tensile force detection unit is lower than an allowable range (S304). The jib shake-out control includes control by the control device 6 to make the second winch execute the operation of winding the second rope.SELECTED DRAWING: Figure 12

Description

[Technical field]

[0001] The present invention relates to a crane and a method for controlling a crane with a boom and a jib. [Background technology]

[0002] A crane may include a boom and a jib (see, for example, Patent Document 1). The boom is connected to a main body so that it can be raised and lowered. The jib is connected to a tip of the boom so that it can be rotated. A hook is connected to a hanging rope that hangs down from the tip of the jib. The boom and the jib are connected at the work site of the crane.

[0003] The crane also includes a jib lock mechanism that locks the jib to the boom when the jib is along the boom. When the connection between the boom and the jib is complete, the boom is in a prone position along the ground.

[0004] Furthermore, when the boom is in the laid-down state, the jib lock mechanism is in a locked state in which the jib is locked to the boom.

[0005] The crane further includes an operation unit that receives operations by an operator. The operation unit includes a plurality of operation levers that receive operations corresponding to the movements of the boom, the jib, and the hook, respectively.

[0006] After the connection of the boom and the jib has been completed, the operator performs pre-work operations on the operation unit to bring the crane into a predetermined reference state.

[0007] The pre-work operations include an operation for raising the boom from the lying down state to a substantially vertical state, an operation for releasing the locked state of the jib lock mechanism, and an operation for swinging the jib out from a state aligned with the boom to a predetermined target angle.

[0008] After performing the pre-work operations, the operator performs operations on the operation unit to cause the crane to perform various types of work.

[0009] On the other hand, after the work using the crane is completed, the operator performs post-processing operations on the operation unit to place the boom and the jib in the lying down position.

[0010] The post-processing operations include operations for rotating the jib to a position where it is locked to the boom and operations for tilting the upright boom to a ground level position.

[0011] After the post-processing operation is performed, the boom and the jib are dismantled. Note that the post-processing operation may be performed in order to prevent the crane from falling over due to a strong wind or the like after the work is completed. [Prior art documents] [Patent documents]

[0012] [Patent Document 1] JP 2006-176242 A Summary of the Invention [Problem to be solved by the invention]

[0013] However, when the boom is raised while the jib lock mechanism is in the locked state, the rope connected to the jib may become loose, which may cause problems with winding the rope on the winch.

[0014] In addition, when the boom is tilting with the jib lock mechanism in the locked state, excessive tension may be applied to the rope connected to the jib, which may cause problems such as rope breakage.

[0015] In order to avoid the ropes from loosening or breaking, the operator must simultaneously operate multiple control levers while checking the conditions of the boom and the jib, which requires the operator to be highly skilled.

[0016] An object of the present invention is to provide a crane control method and a crane that can simplify pre-work operations or post-work operations of a crane. [Means for solving the problem]

[0017] A crane control method according to one aspect of the present invention is a method for controlling a crane. The crane includes a boom, a first rope, a first winch, a boom angle detection unit, a jib, a second rope, a second winch, a jib tension detection unit, a jib lock mechanism, a lock detection unit, a hook, a third rope, a third winch, a drooping length measurement unit, an operation unit, and a control device. The boom is connected to a main body unit so as to be able to be raised and lowered. The first rope is connected to the boom. The first winch changes the angle of the boom by winding up the first rope or letting out the first rope. The boom angle detection unit detects the angle of the boom. The jib is rotatably connected to a tip of the boom. The second rope is connected to the jib. The second winch changes the angle of the jib with respect to the boom by winding up the second rope or letting out the second rope. The jib tension detection unit detects the tension applied to the second rope. The jib lock mechanism locks the jib to the boom when the jib is along the boom, and is capable of releasing the state in which the jib is locked to the boom. The lock detection unit detects the locked state in which the jib locks the jib to the boom by the jib lock mechanism. The hook is a part from which a load is hung. The third rope is connected to the hook and hung from the tip of the jib. The third winch changes the length of the part of the third rope hanging from the tip of the jib by winding up the third rope or letting out the third rope. The hanging length measurement unit measures the rope hanging length, which is the length of the part of the third rope hanging from the tip of the jib. The operation unit accepts a human operation. The control device controls the crane. The crane control method includes, when a pause mode, which is one of a plurality of predetermined control modes, is set and a detection value of the boom angle detection unit is within a predetermined target raising range, and a predetermined first pause operation is being performed on the operating unit, the control device executes jib folding control until the locked state is detected by the lock detection unit.The crane control method further includes the control device executing boom tilt control until the detection value of the boom angle detection unit reaches a predetermined target tilt range when a predetermined second pause operation is performed on the operation unit under the condition that the pause mode is set after the lock state is detected by the lock detection unit. The jib folding control includes the control device causing the second winch to execute an operation of letting out the second rope. The jib folding control further includes the control device causing the third winch to execute an operation of winding the third rope or an operation of letting out the third rope when the rope drooping length is out of a predetermined reference length range. The boom tilt control includes the control device causing the first winch to execute an operation of letting out the first rope. The boom tilt control further includes the control device causing the second winch to execute an operation of letting out the second rope when the detection value of the jib tension detection unit exceeds an allowable range.

[0018] A crane according to another aspect of the present invention includes the boom, the first rope, the first winch, the boom angle detection unit, the jib, the second rope, the second winch, the jib tension detection unit, the jib lock mechanism, the lock detection unit, the hook, the third rope, the third winch, the operation unit, and the control device that realizes the crane control method. Effect of the Invention

[0019] According to the present invention, it is possible to provide a crane control method and a crane that can simplify pre-work operations or post-work operations of a crane. [Brief description of the drawings]

[0020] [Figure 1] FIG. 1 is a configuration diagram of a crane according to an embodiment. [Diagram 2]FIG. 2 is a block diagram showing a configuration of control-related devices in the crane according to the embodiment. [Diagram 3] FIG. 3 is a block diagram showing the configuration of a control device in a crane according to the embodiment. [Figure 4] FIG. 4 is a diagram showing a configuration of a latch device in a crane according to the embodiment. [Diagram 5] FIG. 5 is a diagram showing a latch device in an unlocked state in a crane according to the embodiment. [Figure 6] FIG. 6 is a diagram showing a state in which the boom of the crane according to the embodiment is lowered. [Figure 7] FIG. 7 is a diagram showing a completed state of raising the boom of the crane according to the embodiment. [Figure 8] FIG. 8 is a diagram showing a reference state of the crane according to the embodiment. [Figure 9] FIG. 9 is a diagram showing a state before the jib of the crane according to the embodiment is folded. [Figure 10] FIG. 10 is a diagram showing the jib of the crane according to the embodiment in a folded state. [Figure 11] FIG. 11 is a flowchart showing an example of a procedure of the first start control in the crane according to the embodiment. [Figure 12] FIG. 12 is a flowchart showing an example of a boom raising control procedure in the crane according to the embodiment. [Figure 13] FIG. 13 is a flowchart showing an example of a procedure of the second start control in the crane according to the embodiment. [Figure 14] FIG. 14 is a flowchart showing an example of a procedure for controlling jib swinging in the crane according to the embodiment. [Figure 15] FIG. 15 is a flowchart showing an example of a procedure of the first pause control in the crane according to the embodiment. [Figure 16] FIG. 16 is a flowchart showing an example of a procedure for controlling jib folding in the crane according to the embodiment. [Figure 17]FIG. 17 is a flowchart showing an example of a procedure of the second pause control in the crane according to the embodiment. [Figure 18] FIG. 18 is a flowchart showing an example of a boom tilting control procedure in the crane according to the embodiment. [Figure 19] FIG. 19 is a flowchart showing an example of a procedure for controlling jib folding in the crane according to the first application example. [Figure 20] FIG. 20 is a block diagram showing the configuration of a control device in a crane according to the second application example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that the following embodiment is an example of the present invention, and is not intended to limit the technical scope of the present invention.

[0022] [Configuration of Crane 10] The crane 10 according to the embodiment is a work machine that lifts and moves a load. An example in which the crane 10 is a jib crane will be described below.

[0023] 1, the crane 10 includes a lower body 11, an upper rotating body 12, a cab 13, a gantry 15, a winch device 16, a counterweight 17, a boom 21, a gantry sheave 150, a jib 22, a jib point sheave 220, a strut 23, a latch device 8, a hook 30, a first rope 31, a second rope 32, and a third rope 33. The winch device 16 includes a first winch 161, a second winch 162, and a third winch 163.

[0024] The upper rotating body 12 is a rotating body that is rotatably supported by the lower traveling body 11. The upper rotating body 12 is integrally formed with a cab 13 and a gantry 15.

[0025] The gantry 15 is fixed to the upper rotating body 12 in a state in which it stands up from the upper rotating body 12. Furthermore, the upper rotating body 12 supports a winch device 16, a counterweight 17, and a boom 21. Note that one or both of the second winch 162 and the third winch 163 may be disposed at the base of the boom 21 in some cases.

[0026] The lower travelling body 11 is a base portion that rotatably supports the upper rotating body 12. The upper rotating body 12 is a rotating body that is driven to rotate by a driving source (not shown) provided on the lower travelling body 11.

[0027] The crane 10 shown in Fig. 1 is a mobile crane. Therefore, the crane 10 further includes a traveling device 14. The traveling device 14 supports the lower traveling body 11 and is capable of traveling. Figs. 1, 4 to 8 show an example in which the traveling device 14 is a crawler type device.

[0028] In the crane 10, the lower traveling body 11, the upper rotating body 12 and the traveling device 14 are an example of a main body portion that is directly or indirectly connected to the base portion of the boom 21.

[0029] The cab 13 is a driver's room. The boom 21 has a base portion connected to the upper rotating body 12. The boom 21 can be raised and lowered about the base portion connected to the upper rotating body 12.

[0030] The jib 22 is rotatably connected to the tip of the boom 21. The strut 23 is provided at the connection portion of the boom 21 and the jib 22. The gantry sheave 150 is provided at the tip of the gantry 15. The jib point sheave 220 is provided at the tip of the jib 22.

[0031] The first rope 31 is hung on the gantry sheave 150, and both ends of the first rope 31 are connected to the boom 21 and the first winch 161, respectively. The first winch 161 supports the boom 21 via the first rope 31. The first rope 31 may be referred to as a boom hoisting rope, for example.

[0032] The first winch 161 changes the angle of the boom 21 by winding up the first rope 31 or letting out the first rope 31. Note that the angle of the boom 21 is the elevation angle of the boom 21.

[0033] The second rope 32 is hung on the strut 23, and both ends of the second rope 32 are connected to the jib 22 and the second winch 162, respectively. The second winch 162 supports the boom 21 via the second rope 32. The second rope 32 may be referred to as a jib hoisting rope, for example.

[0034] The second winch 162 changes the angle of the jib 22 relative to the boom 21 by winding in the second rope 32 or letting out the second rope 32.

[0035] The third rope 33 is hung on the jib point sheave 220. The hook 30 is suspended by the third rope 33. That is, the third rope 33 is connected to the hook 30 and hangs down from the tip of the jib 22. The third rope 33 may be referred to as a suspension rope, for example.

[0036] The third winch 163 changes the length of the hanging portion of the third rope 33 by winding up or letting out the third rope 33. The hanging portion is a portion of the third rope 33 that hangs down from the tip end of the jib 22.

[0037] The change in length of the hanging part causes the hook 30 to rise and fall.

[0038] The counterweight 17 balances the load of the boom 21, the jib 22, and the load suspended from the hook 30.

[0039] The latch device 8 is provided on the boom 21. The latch device 8 locks the jib 22 to the boom 21 when the jib 22 is along the boom 21 (see Figs. 4, 5 and 8). In the following description, the state in which the jib 22 is locked to the boom 21 by the latch device 8 is referred to as a locked state.

[0040] Furthermore, the latch device 8 can release the locked state in accordance with an input unlock command. The unlock command is transmitted from a control device 6, which will be described later, to the latch device 8. The jib 22 is locked to the boom 21 by the latch device 8 when, for example, the work by the crane 10 is completed.

[0041] The latch device 8 is an example of a jib lock mechanism that can lock the jib 22 to the boom 21 and release the locked state.

[0042] When the boom 21 is in an upright state, the jib 22 is rotated downward to a position along the boom 21 by letting out the second rope 32, and the latch device 8 locks the jib 22 to the boom 21 (see Figs. 7 and 8). After that, the boom 21 holding the jib 22 is lowered to a position along the ground by letting out the first rope 31 (see Fig. 8).

[0043] For example, the latch device 8 includes an engaging member 81, a slide support member 82, an engaged member 83, a first spring 84, a holding member 85, a second spring 86, and a driving device 87 (see FIGS. 4 and 5).

[0044] The engaged member 83 is fixed to the jib 22. The slide support member 82 is fixed to the boom 21. The engaging member 81 is supported movably between a locked position and an unlocked position. The slide support member 82 supports the engaging member 81 movably.

[0045] FIG. 4 shows the engaging member 81 in the locked position, and FIG. 5 shows the engaging member 81 in the released position.

[0046] In the locked position, the engaging member 81 engages with the engaged member 83. The engaging member 81 engages with the engaged member 83 to lock the jib 22 to the boom 21 (see FIG. 4). That is, the state in which the engaging member 81 engages with the engaged member 83 is the locked state.

[0047] The first spring 84 biases the engaging member 81 toward the locked position. That is, when the jib 22 is in a position along the boom 21, the engaging member 81 engages with the engaged member 83, and the first spring 84 maintains the locked state.

[0048] When the unlock command is input, the drive device 87 moves the engagement member 81 from the locked position to the unlocked position against the biasing force of the first spring 84. This causes the latch device 8 to change from the locked state to the unlocked state (see FIG. 5).

[0049] The unlocked state is a state in which the jib 22 is not locked to the boom 21. In this embodiment, the unlocked state is a state in which the engaging member 81 is not engaged with the engaged member 83.

[0050] When the unlock command is not input to the driving device 87 , the driving device 87 does not restrict the movement of the engaging member 81 , and the biasing force of the first spring 84 acts on the engaging member 81 .

[0051] The holding member 85 is supported movably between a locking position and a retracted position on the boom 21. The holding member 85 is supported movably by a support portion (not shown) provided on the boom 21.

[0052] FIG. 5 shows the holding member 85 in the locking position, and FIG. 4 shows the holding member 85 in the retracted position.

[0053] The holding member 85 holds the engaging member 81 in the release position by locking the engaging member 81 at the locking position (see FIG. 5). A second spring 86 biases the holding member 85 towards the locking position.

[0054] When the jib 22 rotates to a position along the boom 21, the engaged member 83 abuts against the holding member 85. By abutting against the holding member 85, the engaged member 83 moves the holding member 85 from the locking position to the retracted position against the biasing force of the second spring 86 (see FIG. 4).

[0055] When the holding member 85 moves from the locking position to the retracted position, the lock of the engaging member 81 by the holding member 85 is released (see FIG. 4). Therefore, when the holding member 85 moves to the retracted position, the engaging member 81 moves from the release position to the locking position by the biasing force of the first spring 84, and the latch device 8 enters the locked state (see FIG. 4).

[0056] 3, the crane 10 includes drive system devices such as an engine 41, a hydraulic pump 42, a hydraulic control valve 43, and an actuator 44, an operation device 5, a control device 6, and a display device 7. The actuator 44 is a hydraulic actuator. The control device 6 controls the crane 10.

[0057] Devices for human interface such as the operation device 5 and the display device 7 are provided in the cab 13. Furthermore, the crane 10 also includes a status detection device 45 that detects the status of various pieces of equipment included in the crane 10.

[0058] The operation device 5 is a device that accepts operations by the operator. The operation device 5 is an example of an operation unit that accepts operations by a person. The display device 7 is a device that displays information.

[0059] For example, the display device 7 is a panel display device such as a liquid crystal display unit, etc. The operation device 5 includes a lever operation device 51, an operation button 52, an input device 53, and the like.

[0060] The lever operating device 51 includes a plurality of displaceable operating levers 511, 512, and 513. The lever operating device 51 further includes a displacement detection device 510 that outputs an operating signal Sx1 that indicates the displacement state of each of the plurality of operating levers 511, 512, and 513.

[0061] The operation signal Sx1 indicates the direction of displacement of each of the plurality of operation levers 511, 512, and 513 from its home position and the amount of displacement from the home position.

[0062] The multiple operation levers 511 , 512 , 513 include a boom operation lever 511 , a jib operation lever 512 and a hoisting operation lever 513 .

[0063] The boom operation lever 511 receives an operation to instruct the operation of the first winch 161. The jib operation lever 512 receives an operation to instruct the operation of the second winch 162. The hoisting operation lever 513 receives an operation to instruct the operation of the third winch 163.

[0064] The displacement directions of the multiple operating levers 511, 512, 513 indicate the winding or unwinding operations of the corresponding multiple winches 161, 162, 163. The displacement amounts of the multiple operating levers 511, 512, 513 indicate the operating speeds of the corresponding multiple winches 161, 162, 163.

[0065] The input device 53 accepts information input by the operator. For example, the input device 53 is a touch panel that is integrated with the display device 7. The input device 53 may also be a device that accepts information input by voice operation of the operator.

[0066] The state detection device 45 includes a load meter 451, a jib tension sensor 452, a lock sensor 453, a boom angle meter 454, and a jib angle meter 455. The detection results of the various state detection devices 45 are input to the control device 6.

[0067] The load meter 451 detects the weight of the load suspended from the hook 30. The jib tension sensor 452 detects the tension acting on the second rope 32. The jib tension sensor 452 is an example of a jib tension detection unit.

[0068] For example, the jib tension sensor 452 is a load sensor such as a load cell attached to a connecting member that connects the jib 22 and the second rope 32.

[0069] The lock sensor 453 is an example of a lock detection unit that detects the locked state. For example, the lock sensor 453 is a proximity switch or a limit switch that detects the engagement member 81 of the latch device 8 when the engagement member 81 is in the locked position (see FIGS. 4 and 5).

[0070] The boom angle meter 454 is an example of a boom angle detection unit that detects the angle of the boom 21. The jib angle meter 455 is an example of a jib angle detection unit that detects the angle of the jib 22.

[0071] For example, it is conceivable that the boom angle meter 454 is an inclinometer attached to the boom 21. In this case, the boom angle meter 454 detects the angle that the longitudinal direction of the boom 21 forms with respect to the horizontal direction.

[0072] Similarly, the jib angle meter 455 may be an inclinometer attached to the jib 22. In this case, the jib angle meter 455 detects the angle that the longitudinal direction of the jib 22 makes with respect to the horizontal direction.

[0073] Furthermore, the state detection device 45 includes a reeled-out length measuring device 456. The reeled-out length measuring device 456 is a device that measures the reeled-out length of the third rope 33.

[0074] For example, the payout length measuring device 456 measures the payout length of the third rope 33 by counting the number of rotations of a rotating body that is in contact with the third rope 33 and rotates following the rotation.

[0075] The engine 41 drives the hydraulic pump 42. For example, the engine 41 is a diesel engine. The hydraulic control valve 43 supplies compressed oil to an actuator 44 in accordance with a control signal output from the control device 6.

[0076] The actuator 44 includes a first winch motor 441, a second winch motor 442, and a third winch motor 443, which are hydraulic motors. Furthermore, the actuator 44 includes a first negative brake 444, a second negative brake 445, and a third negative brake 446.

[0077] The first winch motor 441 is a drive unit for the first winch 161. The first negative brake 444 is a brake for the first winch 161. The control device 6 releases the first negative brake 444 and further operates the first winch motor 441, thereby operating the first winch 161.

[0078] The second winch motor 442 is a drive unit of the second winch 162. The second negative brake 445 is a brake for the second winch 162. The control device 6 releases the second negative brake 445 and further operates the second winch motor 442, thereby operating the second winch 162.

[0079] The third winch motor 443 is a drive unit of the third winch 163. The third negative brake 446 is a brake of the third winch 163. The control device 6 releases the third negative brake 446 and further operates the third winch motor 443, thereby operating the third winch 163.

[0080] The actuator 44 further includes a rotation motor (not shown) that rotates the upper rotating body 12. The rotation motor is also a hydraulic motor.

[0081] The control device 6 outputs a control signal to a controlled object such as the hydraulic control valve 43 in response to an operation on the operating device 5 or detection results of various state detection devices 45. Furthermore, the control device 6 starts the engine 41 when a start operation is performed on the operating device 5. The control device 6 also controls the display device 7.

[0082] 3, the control device 6 includes a micro processing unit (MPU) 601, a random access memory (RAM) 602, a non-volatile memory 603, and a signal interface 604. The RAM 602 and the non-volatile memory 603 are computer-readable storage devices.

[0083] The MPU 601 is an example of a processor that executes various types of data processing and control by executing programs stored in advance in the non-volatile memory 603 .

[0084] The RAM 602 is a volatile memory that temporarily stores the programs executed by the MPU 601 and data derived or referenced by the MPU 601 .

[0085] The non-volatile memory 603 pre-stores the programs executed by the MPU 601 and data referenced by the MPU 601. For example, the non-volatile memory 603 may be an EEPROM (Electrically Erasable Programmable Read Only Memory) or a flash memory.

[0086] The signal interface 604 converts the detection signal of the state detection device 45 into digital data and transmits it to the MPU 601. Furthermore, the signal interface 604 converts the control command output by the MPU 601 into a control signal such as a current signal or a voltage signal, and outputs it to the device to be controlled.

[0087] The crane 10 may be equipped with a boom tension sensor (not shown) that detects the tension acting on the first rope 31. In this case, the load meter 451 may be composed of the boom tension sensor, the jib tension sensor 452, and the MPU 601 that executes the load derivation process.

[0088] In the load derivation process, the MPU 601 derives the weight of the suspended load based on the detection values ​​of the boom tension sensor, the jib tension sensor 452, the boom angle meter 454, and the jib angle meter 455.

[0089] Moreover, the control device 6 operates as a drooping length deriving unit 60 by the MPU 601 executing a predetermined calculation program (see FIG. 2).

[0090] The hanging length derivation unit 60 derives the rope hanging length based on the measurement result of the payout length measuring device 456 and the preset lengths of the boom 21 and the jib 22. The rope hanging length is the length of the hanging part of the third rope 33. The hanging part is the part of the third rope 33 that hangs down from the tip of the jib 22.

[0091] In addition, the hanging length derivation unit 60 may correct the rope hanging length based on the angles detected by the boom angle meter 454 and the jib angle meter 455.

[0092] The payout length measuring device 456 and the hanging length derivation unit 60 are an example of a hanging length measuring unit that measures the rope hanging length.

[0093] The hanging length measuring unit may be configured with a camera and an image processing device that processes an image obtained by the camera. The camera is disposed on the upper rotating body 12 and captures an image of the hanging portion of the third rope 33.

[0094] The image processing device extracts an image of the hanging portion of third rope 33 from the image obtained by the camera. Furthermore, the image processing device derives the distance to the hanging portion of third rope 33 based on the lengths of boom 21 and jib 22, respectively, and the angles detected by boom angle meter 454 and jib angle meter 455.

[0095] The image processing device derives the rope hanging length based on the length of the image of the hanging portion of third rope 33 and the distance to the hanging portion of third rope 33.

[0096] The connection of the boom 21 to the upper rotating body 12 and the connection of the jib 22 to the boom 21 are performed at the work site of the crane 10.

[0097] When the connection between the boom 21 and the jib 22 is complete, the boom 21 is in a lying state along the ground (see FIG. 6). When the boom 21 is in the lying state, the latch device 8 is in the locked state.

[0098] After the connection of the boom 21 and the jib 22 is completed, the crane 10 is brought into a predetermined reference state (see FIG. 8). In the reference state, the boom 21 stands approximately vertically, and the jib 22 is swung out to a predetermined target angle.

[0099] On the other hand, after the work by the crane 10 is completed, the boom 21 is brought into the lying down state (see FIG. 6). After the boom 21 is brought into the lying down state, the boom 21, the jib 22, etc. are dismantled.

[0100] Incidentally, when the boom 21 is being raised with the latch device 8 in the locked state, the second rope 32 connected to the jib 22 may become loose. The looseness of the second rope 32 may cause poor winding of the second rope 32 in the second winch 162.

[0101] In addition, when the boom 21 is tilting with the latch device 8 in the locked state, excessive tension may be applied to the second rope 32 connected to the jib 22. The application of excessive tension to the second rope 32 may cause problems such as breakage of the second rope 32.

[0102] In order to avoid slackening or breakage of the second rope 32, the operator needs to simultaneously operate the boom operation lever 511 and the jib operation lever 512 while checking the conditions of the boom 21 and the jib 22. Such an operation requires the operator's skill.

[0103] In the crane 10, the control device 6 executes start control, which will be described later (see Figs. 11 to 14). As a result, the crane 10 is ready to start work simply by performing a simple operation on the operation device 5.

[0104] The start control process is an example of a crane control method. This crane control method is realized by the MPU 601 of the control device 6. As will be described later, the start control includes a first start control (FIG. 11) and a second start control (FIG. 13).

[0105] Furthermore, the control device 6 executes a pause control, which will be described later (FIGS. 15 to 18). This allows the crane 10 to be paused in the lying down state simply by performing a simple operation on the operation device 5.

[0106] The pause control process is an example of a crane control method. This crane control method is realized by the MPU 601 of the control device 6. As described later, the pause control includes a first pause control (FIG. 15) and a second pause control (FIG. 17).

[0107] The control device 6 selects one of a plurality of predetermined control modes and executes control corresponding to the selected mode. The plurality of control modes include a normal mode, a start mode, and a pause mode. The start mode and the pause mode are each an example of a predetermined special mode.

[0108] Moreover, the control device 6 operates as a normal control unit 61, a start control unit 62, or a pause control unit 63 by the MPU 601 executing a predetermined control program (see FIG. 2).

[0109] When the normal mode is selected, a normal control unit 61 operates. When the start mode is selected, a start control unit 62 operates. When the pause mode is selected, a pause control unit 63 operates.

[0110] The control device 6 selects the normal mode when started up, so that the normal control unit 61 operates when the control device 6 is started up.

[0111] The normal control unit 61 executes normal control over the actuator 44 in accordance with the operation of the operating device 5 .

[0112] Specifically, when the boom operation lever 511 is operated, the normal control unit 61 controls the first winch 161 in accordance with the displacement direction and displacement amount of the boom operation lever 511. The boom operation lever 511 accepts an operation that instructs the operation of the first winch 161 when the normal mode is set.

[0113] Similarly, when an operation is performed on the jib operation lever 512, the normal control unit 61 controls the second winch 162 in accordance with the displacement direction and displacement amount of the jib operation lever 512. The jib operation lever 512 accepts an operation to instruct the operation of the second winch 162 when the normal mode is set.

[0114] Similarly, when the hoisting operation lever 513 is operated, the normal control unit 61 controls the third winch 163 in accordance with the displacement direction and displacement amount of the hoisting operation lever 513. When the normal mode is set, the hoisting operation lever 513 accepts an operation to instruct the operation of the third winch 163.

[0115] The normal control unit 61 selects the start mode when a predetermined first mode setting operation is performed on the operation device 5. This causes the start control unit 62 to operate. The start control unit 62 executes the first start control, and then executes the second start control.

[0116] Furthermore, the start control unit 62 selects the normal mode when the second start control ends, whereby the normal control unit 61 operates.

[0117] The normal control unit 61 selects the pause mode when a predetermined second mode setting operation is performed on the operation device 5. This causes the pause control unit 63 to operate. The pause control unit 63 executes the first pause control, and then executes the second pause control.

[0118] Moreover, the pause control unit 63 selects the normal mode when the second pause control ends, whereby the normal control unit 61 operates.

[0119] For example, the first mode setting operation and the second mode setting operation are operations on the operation button 52 or operations on the input device 53.

[0120] The second mode setting operation may be the same as the first mode setting operation. For example, the control device 6 can determine whether a certain operation corresponds to the start mode or the pause mode depending on the detection state of the locked state by the lock sensor 453.

[0121] It should be noted that the hanging length derivation unit 60 executes the process of deriving the rope hanging length regardless of which of the plurality of control modes is selected.

[0122] [First start control] Next, an example of a procedure of the first start control will be described with reference to the flowchart shown in FIG.

[0123] The start control unit 62 executes the first start control in a situation where the start mode is set and the locked state of the latch device 8 is detected by the lock sensor 453.

[0124] The start mode is set when the boom 21 is in the lying down state (see FIG. 6). When the start mode is set, the start control unit 62 causes the display device 7 to display information indicating that the start mode is set. The information indicating that the start mode is set is one or both of an image and a character string.

[0125] In the following description, S101, S102, ... represent identification symbols of a plurality of steps in the first start control. In the first start control, the start control unit 62 starts the process from step S101.

[0126] <Process S101> In step S101 and step S102 described later, the start control unit 62 checks an operation on the operation device 5. When a predetermined first start operation is performed on the operation device 5, the start control unit 62 executes the process of step S103.

[0127] For example, the first start operation is an operation on one of the boom operation lever 511 and the jib operation lever 512.

[0128] In this embodiment, the first start operation is a pulling operation on the boom operation lever 511. The pulling operation on the boom operation lever 511 is an operation on the boom operation lever 511 when an operation of winding up the first rope 31 is instructed in the normal mode.

[0129] On the other hand, when the first start operation on the operation device 5 is not performed, the start control unit 62 executes the process of step S102.

[0130] <Process S102> In step S102, the start control unit 62 checks whether or not an operation other than the first start operation has been performed on the operation device 5. When an operation other than the first start operation has been performed on the operation device 5, the start control unit 62 executes the process of step S105.

[0131] On the other hand, when the first start operation and other operations on the operation device 5 have not been performed, the start control unit 62 shifts the process to step S101.

[0132] <Process S103> In step S103, the start control unit 62 determines whether the boom angle detection value θ1 has reached a predetermined target erection angle θ11 or more. The boom angle detection value θ1 is a detection value of the boom angle meter 454.

[0133] The boom angle detection value θ1 reaching the target raising angle θ11 or more is an example of the boom angle detection value θ1 reaching within a predetermined target raising range.

[0134] 7 shows the erected state of the boom 21. The erected state is the state of the boom 21 when the boom angle detection value θ1 reaches or exceeds the target erected angle θ11. For example, the target erected angle θ11 is set within the range from 85 degrees to 89 degrees.

[0135] The start control unit 62 executes the process of step S104 when it determines that the boom angle detection value θ1 has not reached the target erection angle θ11 or more.

[0136] On the other hand, when it is determined that the boom angle detection value θ1 has reached the target erection angle θ11 or more, the start control unit 62 executes the process of step S106.

[0137] <Process S104> In step S104, the start control unit 62 executes the boom raising control described below (see FIG. 12).

[0138] In the boom raising control, the start control unit 62 executes control for raising the boom 21 from the laid-down state shown in FIG. 6 to the raised state shown in FIG.

[0139] After executing the boom raising control, the start control unit 62 shifts the process to step S101. When the first start operation is performed on the operation device 5, the start control unit 62 executes the boom raising control until the boom angle detection value θ1 reaches or exceeds the target raising angle θ11 (step S104).

[0140] <Process S105> In step S105, the start control unit 62 executes normal control in response to an operation other than the first start operation on the operating device 5. The normal control is control executed by the normal control unit 61 in the normal mode.

[0141] For example, while the boom 21 is rising from the laid-down state to the raised state, the operator may stop the first starting operation and perform an operation for lifting the hook 30 off the ground.

[0142] The ground raising is to raise the hook 30 to a position higher than the ground. The operation for the ground raising is an operation on the hoisting operation lever 513.

[0143] Therefore, in step S102, there are cases where an operation of the hoisting operation lever 513 is detected. In this case, in step S105, the start control unit 62 controls the operation direction and operation speed of the third winch 163 according to the displacement direction and displacement amount of the hoisting operation lever 513.

[0144] After executing the process of step S105, the start control unit 62 shifts the process to step S101. For example, the start control unit 62 executes the processes of steps S101 to S105 at a predetermined cycle.

[0145] The boom raising control is executed when the first start operation is performed on the operation device 5 under a situation in which the start mode is set and the locked state is detected by the lock sensor 453.

[0146] Furthermore, the start control unit 62 executes the processing of steps S101 to S105 including the boom raising control until the boom angle detection value θ1 reaches or exceeds the target raising angle θ11. That is, the start control unit 62 ends the processing of steps S101 to S105 including the boom raising control when the boom angle detection value θ1 reaches or exceeds the target raising angle θ11.

[0147] <Process S106> In step S106, the start control unit 62 executes a phase transition notification for notifying the operator that the boom angle detection value θ1 has reached the target raising angle θ11 or more.

[0148] For example, the phase transition notification includes a message display process for causing the display device 7 to display a message.

[0149] In addition, the crane 10 may include a vibration device that vibrates an operation lever that is a target of the first start operation. In this case, the phase transition notification may include a process of causing the vibration device to vibrate the operation lever.

[0150] Each of the display device 7 and the vibration device is an example of a notification section that executes a notification process for the person operating the operation device 5.

[0151] After issuing the phase transition notification in step S106, the start control unit 62 executes the process of step S107. The process of step S107 is executed when the boom angle detection value θ1 reaches the target erection angle θ11 or more.

[0152] <Process S107> In step S107, the start control unit 62 causes the latch device 8 to execute an operation to release the locked state. Specifically, the start control unit 62 outputs the unlock command to the latch device 8. As a result, the latch device 8 changes from the locked state to the unlocked state.

[0153] Furthermore, the start control unit 62 executes the process of step S108. The process of step S107 is an example of unlock control.

[0154] <Process S108> In step S108, the start control unit 62 checks the detection state of the lock sensor 453.

[0155] The start control unit 62 executes the process of step S109 when the locked state is not detected by the lock sensor 453. On the other hand, the start control unit 62 executes the process of step S110 when the locked state is detected by the lock sensor 453.

[0156] <Process S109> In step S109, the start control unit 62 executes the phase transition notification for notifying the operator that the locked state has been released. The process of step S109 is similar to the process of step S106.

[0157] Furthermore, the start control unit 62 ends the first start control, and executes the second start control (see FIG. 13). The second start control will be described later.

[0158] <Process S110> In step S110, the start control unit 62 executes an error notification process. For example, the start control unit 62 causes a predetermined error message to be displayed on the display device 7. After that, the start control unit 62 shifts the process to step S108.

[0159] [Boom elevation control] Next, an example of a procedure for the boom raising control will be described with reference to the flowchart shown in FIG.

[0160] In the following description, S201, S202, ... represent identification symbols of a plurality of steps in the boom raising control. In the boom raising control, the start control unit 62 starts the process from step S201.

[0161] <Process S201> In step S201, the start control unit 62 causes the first winch 161 to execute the winding operation of the first rope 31. At that time, the start control unit 62 operates the first winch 161 at a speed according to the displacement amount of the operating lever that is the target of the first start operation.

[0162] In step S201, the start control unit 62 may limit the acceleration of the winding of the first rope 31 by the first winch 161 to a range not exceeding a predetermined first upper limit acceleration. In this case, the start control unit 62 accelerates the operation of the first winch 161 at the first upper limit acceleration when the acceleration of the displacement of the operating lever that is the target of the first start operation exceeds a predetermined acceleration.

[0163] Furthermore, the start control unit 62 executes the process of step S202.

[0164] <Process S202> In step S202 and in step S203 described later, the start control unit 62 checks the jib tension detection value F2, which is the detection value of the jib tension sensor 452.

[0165] The start control unit 62 executes the process of step S204 when the jib tension detection value F2 is below a predetermined allowable lower limit value F21. On the other hand, the start control unit 62 executes the process of step S203 when the jib tension detection value F2 is not below the allowable lower limit value F21.

[0166] <Process S203> In step S203, the start control unit 62 checks whether the jib tension detection value F2 is greater than a predetermined allowable upper limit value F22.

[0167] The range from the allowable lower limit value F21 to the allowable upper limit value F22 is the allowable range of the tension applied to the second rope 32.

[0168] The start control unit 62 executes the process of step S205 when the jib tension detection value F2 exceeds the allowable upper limit value F22. On the other hand, the start control unit 62 executes the process of step S206 when the jib tension detection value F2 does not exceed the allowable upper limit value F22.

[0169] <Process S204> In step S204, the start control unit 62 causes the second winch 162 to perform the winding operation of the second rope 32.

[0170] For example, in step S204, the start control unit 62 operates the second winch 162 at a predetermined speed. Also, in step S204, the start control unit 62 may operate the second winch 162 at a speed according to the difference between the allowable lower limit value F21 and the jib tension detection value F2.

[0171] In addition, in step S204, the start control unit 62 may operate the second winch 162 for a time period according to the difference between the allowable lower limit value F21 and the jib tension detection value F2. Furthermore, the start control unit 62 executes the process of step S206.

[0172] The processing of steps S202 and S204 prevents the second rope 32 from becoming loose during the process of raising the boom 21. Here, the processing of steps S202 and S204 is executed only when the first start operation is executed. That is, the processing of steps S202 and S204 is executed even if a plurality of operations are not executed simultaneously.

[0173] <Process S205> In step S205, the start control unit 62 causes the second winch 162 to execute the operation of reeling out the second rope 32.

[0174] For example, in step S205, the start control unit 62 operates the second winch 162 at a predetermined speed. Also, in step S205, the start control unit 62 may operate the second winch 162 at a speed according to the difference between the allowable lower limit value F21 and the jib tension detection value F2.

[0175] Furthermore, in step S205, the start control unit 62 may operate the second winch 162 for a period of time according to the difference between the jib tension detection value F2 and the allowable upper limit value F22. Furthermore, the start control unit 62 executes the process of step S206.

[0176] By performing the processes of steps S202 to S205, it is possible to prevent the second rope 32 from becoming loose and from being subjected to excessive tension while the boom raising control is being executed.

[0177] Therefore, problems such as poor winding of the second rope 32 by the second winch 162 or breakage of the second rope 32 are avoided.

[0178] The process of step S205 is an exceptional process that is not usually executed while the boom raising control is being performed.

[0179] <Process S206> In step S206, the start control unit 62 derives the jib point position that changes due to the operation of the first winch 161, based on the boom angle detection value θ1. The jib point position is the position of the tip of the jib 22.

[0180] The start control unit 62 derives the position of the tip of the jib 22 based on the main body unit, based on the dimensional information of the boom 21 and the jib 22 and the boom angle detection value θ1. The dimensional information of the boom 21 and the jib 22 is known information.

[0181] The jib point position includes information on the horizontal position of the tip of the jib 22 and information on the vertical position of the tip of the jib 22. Therefore, the process of deriving the jib point position includes a process of deriving a jib point height, which is the position of the tip of the jib 22 in the up-down direction.

[0182] Furthermore, the start control unit 62 executes the process of step S207.

[0183] <Process S207> In step S207, the start control unit 62 derives a distance change amount that is a change amount of the distance between the jib point position and the hook position. The hook position is a position of the hook 30 that is set in advance.

[0184] For example, the hook position is set based on the position of the tip of the jib 22 when the boom 21 is in the lying down state. The start control unit 62 further executes the process of step S208.

[0185] <Process S208> In step S208, the start control unit 62 determines whether or not a predetermined ground cutting condition is met.

[0186] The ground-cutting condition is a condition that indicates that the ground-cutting of the hook 30 is performed by winding up the third rope 33 by the third winch 163. In general, the ground-cutting of the hook 30 is performed in a state in which the boom 21 is raised to an angle of about 70 degrees to 85 degrees.

[0187] For example, the ground-cut condition may be a first ground-cut condition or a second ground-cut condition. Also, the ground-cut condition may be a logical AND or a logical OR of the first ground-cut condition and the second ground-cut condition.

[0188] The first ground cutting condition is a condition in which, when the start mode is set and the locked state is detected by the lock sensor 453, a pulling operation is performed on the lifting operation lever 513 when the first start operation is not being performed.

[0189] The pulling operation on the operation lever 513 is an example of an operation for instructing the third winch 163 to perform an operation of winding up the third rope 33. The first ground cutting condition is met when a pulling operation on the hoisting operation lever 513 is detected in step S102 of FIG.

[0190] The second ground cutting condition is a condition that a predetermined confirmation operation is performed on the operation button 52 or the input device 53. The operator performs the confirmation operation when the ground cutting of the hook 30 is performed.

[0191] On the other hand, when it is determined that the ground cutting condition is not satisfied, the start control unit 62 executes the process of step S209.

[0192] On the other hand, when it is determined that the ground-cutting condition is satisfied, the start control unit 62 ends the boom raising control, whereby the start control unit 62 shifts the process to step S101 in FIG.

[0193] <Process S209> In step S209, the start control unit 62 causes the third winch 163 to execute an operation of paying out the third rope 33 by a length corresponding to the distance change amount.

[0194] After executing the process of step S209, the start control unit 62 ends the boom raising control, whereby the start control unit 62 shifts the process to step S101 in FIG.

[0195] The processes of steps S206, S207, and S209 are an example of hook movement prevention control for preventing the hook 30 from moving while in contact with the ground. The start control unit 62 executes the hook movement prevention control until the ground-cutting condition is satisfied (see step S209). On the other hand, the start control unit 62 does not execute the control of the third winch 163 in the hook movement prevention control after the ground-cutting condition is satisfied (see step S208).

[0196] [Second Start Control] Next, an example of a procedure of the second start control will be described with reference to the flowchart shown in FIG.

[0197] The start control unit 62 executes the second start control after the locked state of the latch device 8 is no longer detected by the lock sensor 453 in a situation in which the start mode is set.

[0198] In the following description, S301, S302, ... represent identification symbols of a plurality of steps in the second start control. In the second start control, the start control unit 62 starts the process from step S301.

[0199] <Process S301> In step S301 and step S302 described later, the start control unit 62 checks an operation on the operation device 5. When a predetermined second start operation is performed on the operation device 5, the start control unit 62 executes the process of step S303.

[0200] For example, the second start operation is an operation for one of the boom operation lever 511 and the jib operation lever 512. The second start operation may be the same as the first start operation.

[0201] For example, the second start operation is a pulling operation on the boom operation lever 511. The pulling operation on the boom operation lever 511 is an operation on the boom operation lever 511 when an operation of winding up the first rope 31 is instructed in the normal mode.

[0202] Moreover, the second start operation may be a pulling operation on the jib operation lever 512. The pulling operation on the jib operation lever 512 is an operation on the jib operation lever 512 when an operation of winding up the second rope 32 is instructed in the normal mode.

[0203] On the other hand, when the second start operation on the operation device 5 is not performed, the start control unit 62 executes the process of step S302.

[0204] <Process S302> In step S302, the start control unit 62 checks whether or not an operation other than the second start operation has been performed on the operation device 5. When an operation other than the second start operation has been performed on the operation device 5, the start control unit 62 executes the process of step S305.

[0205] On the other hand, when the second start operation and other operations on the operation device 5 are not being performed, the start control unit 62 shifts the process to step S301.

[0206] <Process S303> In step S303, the start control unit 62 determines whether the detected jib angle value θ2 has reached a preset target work angle θ21 or more. The detected jib angle value θ2 is a value detected by the jib angle meter 455.

[0207] FIG. 8 shows an example of a reference state which is a state of the crane 10 when the detected jib angle value θ2 reaches the target work angle θ21.

[0208] The start control unit 62 executes the process of step S304 when it determines that the detected jib angle value θ2 has not reached the target work angle θ21 or more.

[0209] On the other hand, when the start control unit 62 determines that the detected jib angle value θ2 has reached the target work angle θ21 or more, it executes the process of step S306.

[0210] <Process S304> In step S304, the start control unit 62 executes the jib swing-out control described later (see FIG. 14). In the jib swing-out control, the start control unit 62 executes control for rotating the jib 22 from the folded state shown in FIG. 7 to the extended state shown in FIG.

[0211] The start control unit 62 executes the jib swing-out control when the second start operation is performed on the operating device 5 under the condition that the start mode is set (step S304). The start control unit 62 executes the jib swing-out control until the jib angle detection value θ2 reaches the target work angle θ21 or more. After executing the jib swing-out control, the start control unit 62 shifts the process to step S301.

[0212] <Process S305> In step S305, the start control unit 62 executes normal control in response to an operation other than the second start operation on the operating device 5. The processes in steps S302 and S305 are the same as the processes in steps S102 and S105 in FIG.

[0213] After executing the process of step S305, the start control unit 62 shifts the process to step S301. For example, the start control unit 62 executes the processes of steps S301 to S305 at a predetermined cycle.

[0214] <Process S306> In step S306, the start control unit 62 executes the phase transition notification for notifying the operator that the jib angle detection value θ2 has reached the target working angle θ21 or more. The process of step S306 is similar to the process of step S106.

[0215] After executing the process of step S306, the start control unit 62 ends the second start control, whereby the start control ends.

[0216] [Jib swing control] Next, an example of a procedure for the jib swing-out control will be described with reference to the flowchart shown in Fig. 14. The jib swing-out control is executed when the locked state of the latch device 8 is released under a condition in which the boom 21 is in the upright state.

[0217] In the following description, S401, S402, ... represent identification codes of a plurality of steps in the jib swing control. The start control unit 62 starts the process of step S401 in the jib swing control.

[0218] <Process S401> In step S401, the start control unit 62 causes the second winch 162 to execute the winding operation of the second rope 32. At that time, the start control unit 62 operates the second winch 162 at a speed according to the displacement amount of the operating lever that is the target of the second start operation.

[0219] In step S401, the start control unit 62 may limit the acceleration of the winding of the second rope 32 by the second winch 162 to a range not exceeding a predetermined second upper limit acceleration. In this case, the start control unit 62 accelerates the operation of the second winch 162 at the second upper limit acceleration when the acceleration of the displacement of the operating lever that is the target of the second start operation exceeds a predetermined acceleration.

[0220] Furthermore, the start control unit 62 executes the process of step S402.

[0221] <Process S402> In step S402, the start control unit 62 derives the jib point position that changes due to the operation of the second winch 162, based on the boom angle detection value θ1 and the jib angle detection value θ2.

[0222] The start control unit 62 derives the jib point position based on the dimensional information of the boom 21 and the jib 22, the boom angle detection value θ1, and the jib angle detection value θ2. The dimensional information of the boom 21 and the jib 22 is known information.

[0223] As described above, the jib point position includes information on the jib point height. Furthermore, the start control unit 62 executes the process of step S403.

[0224] <Process S403> In step S403, the start control unit 62 derives a point rise amount. The point rise amount is the rise amount of the tip of the jib 22 that is raised by the process of step S401. In other words, the point rise amount is the change amount of the jib point height.

[0225] The start control unit 62 further executes the process of step S404.

[0226] <Process S404> In step S404, the start control unit 62 causes the third winch 163 to execute an operation of paying out the third rope 33 by a length corresponding to the point increase amount.

[0227] After executing the process of step S404, the start control unit 62 ends the jib swinging control. As a result, the start control unit 62 shifts the process to step S301 in FIG.

[0228] The processing of steps S402 to S404 is for maintaining the distance from the ground to the hook 30 at the distance when the above-mentioned ground lifting is performed (see FIG. 8). By the processing of steps S402 to S404, when the crane 10 reaches the above-mentioned reference state, the operator can quickly perform slinging work near the ground.

[0229] Furthermore, the start control unit 62 causes the notification unit to execute the phase transition notification when a predetermined notification condition is satisfied in a situation where the start mode is set (see steps S106 and S109 in FIG. 11 and step S306 in FIG. 13). The phase transition notification process is an example of a notification process.

[0230] The notification conditions include a first notification condition corresponding to step S106, a second notification condition corresponding to step S109, and a third notification condition corresponding to step S306.

[0231] The first notification condition is a condition that the boom angle detection value θ1 has reached a target erection angle θ11 or more (see step S103 in FIG. 11).

[0232] The second notification condition is a condition that the locked state is no longer detected by the lock sensor 453 (see step S108 in FIG. 11).

[0233] The third notification condition is a condition that the detected jib angle value θ2 reaches the target work angle θ21 (see step S303 in FIG. 13).

[0234] By the phase transition notification, the operator can recognize that there has been a change in the phase of control in the crane 10. Note that only a part of the first notification condition, the second notification condition, and the third notification condition may be adopted as the normal condition.

[0235] In the swing control, when a predetermined release end condition is satisfied, the start control unit 62 stops outputting the unlock command to the latch device 8. As described above, the start control unit 62 outputs the unlock command to the latch device 8 in step S107 of FIG.

[0236] For example, the termination condition includes a first termination condition, a first termination condition, or a second termination condition.

[0237] The first release condition is that the jib angle detection value θ2 reaches a predetermined target route angle. The target route angle is an angle between the angle of the jib 22 in the folded state and a target working angle θ21.

[0238] The second release condition is a condition that the jib angle detection value θ2 has changed by a predetermined target change angle after the lock release command is output.

[0239] The third release condition is a condition that the winding operation of the second rope 32 by the second winch 162 is performed for a predetermined time after the lock release command is output.

[0240] [First pause control] Next, an example of a procedure of the first pause control will be described with reference to the flowchart shown in FIG.

[0241] The pause control unit 63 executes the first pause control in a situation where the pause mode is set and the boom angle detection value θ1 is equal to or greater than the target raising angle θ11.

[0242] The pause mode is set when the boom 21 is in the upright state (see FIG. 9). When the pause mode is set, the pause control unit 63 causes the display device 7 to display information indicating that the pause mode is set. The information indicating that the pause mode is set is one or both of an image and a character string.

[0243] In the following description, S501, S502, ... represent identification symbols of a plurality of steps in the second start control. In the second start control, the pause control unit 63 starts the process from step S501.

[0244] <Process S501> In step S501 and step S502 described later, the pause control unit 63 checks an operation on the operation device 5. The pause control unit 63 executes the process of step S503 when a predetermined first pause operation is performed on the operation device 5.

[0245] For example, the first pause operation is an operation on one of the boom operation lever 511 and the jib operation lever 512.

[0246] In this embodiment, the first pause operation is a pushing operation on the jib operation lever 512. The pushing operation on the jib operation lever 512 is an operation on the jib operation lever 512 when an operation of paying out the second rope 32 is instructed in the normal mode.

[0247] On the other hand, when the first pause operation on the operation device 5 is not performed, the pause control unit 63 executes the process of step S502.

[0248] <Process S502> In step S502, the pause control unit 63 checks whether or not an operation other than the first pause operation has been performed on the operation device 5. When an operation other than the first pause operation has been performed on the operation device 5, the pause control unit 63 executes the process of step S505.

[0249] On the other hand, when the first pause operation and other operations on the operation device 5 are not being performed, the pause control unit 63 shifts the process to step S501.

[0250] <Process S503> In step S503, the pause control unit 63 checks the state of the lock sensor 453. When the lock sensor 453 does not detect the locked state, the pause control unit 63 executes the process of step S504.

[0251] On the other hand, when the lock sensor 453 detects the locked state, the pause control unit 63 executes the process of step S506.

[0252] <Process S504> In step S504, the pause control unit 63 executes the jib folding control described later (see FIG. 16).

[0253] In the jib control, the pause control unit 63 executes control for tilting the jib 22 from the extended state shown in FIG. 9 toward the folded state shown in FIG.

[0254] After executing the jib folding control, the pause control unit 63 shifts the process to step S501. When the first pause operation is performed on the operation device 5, the pause control unit 63 executes the jib folding control until the locked state is detected (step S504).

[0255] <Process S505> In step S505, the pause control unit 63 executes the normal control in response to an operation other than the first pause operation on the operation device 5. The processes in steps S502 and S505 are the same as the processes in steps S102 and S105 in FIG.

[0256] After executing the process of step S505, the pause control unit 63 shifts the process to step S501. For example, the pause control unit 63 executes the processes of steps S501 to S505 at a predetermined cycle.

[0257] When the pause mode is set and the boom angle detection value θ1 is equal to or greater than the target raising angle θ11, the pause control unit 63 executes the jib folding control when the first pause operation is being performed on the operation device 5.

[0258] Furthermore, the pause control unit 63 executes the processes of steps S501 to S505, including the jib folding control, until the locked state is detected by the lock sensor 453. That is, when the locked state is detected by the lock sensor 453, the pause control unit 63 ends the processes of steps S501 to S505, including the jib folding control.

[0259] <Process S506> In step S506, the pause control unit 63 executes the phase transition notification for notifying the operator that the locked state has been detected. The process of step S506 is similar to the process of step S106 or step S108 in FIG.

[0260] Furthermore, the pause control unit 63 ends the first pause control, and executes the second pause control (see FIG. 17). The second pause control will be described later.

[0261] [Jib folding control] Next, an example of the procedure for controlling the folding of the jib will be described with reference to the flowchart shown in FIG.

[0262] In the following description, S601, S602, ... represent identification codes of a plurality of steps in the jib folding control. In the jib folding control, the pause control unit 63 starts with the processing of step S601.

[0263] <Process S601> In step S601, the pause control unit 63 causes the second winch 162 to execute the operation of reeling out the second rope 32. At that time, the pause control unit 63 operates the second winch 162 at a speed according to the displacement amount of the operating lever that is the target of the first pause operation.

[0264] In step S601, the pause control unit 63 may limit the acceleration of the payout of the second rope 32 by the second winch 162 to a range not exceeding a predetermined third upper limit acceleration. In this case, the pause control unit 63 accelerates the operation of the second winch 162 at the third upper limit acceleration when the acceleration of the displacement of the operating lever that is the target of the second pause operation exceeds a predetermined acceleration.

[0265] Furthermore, the pause control unit 63 executes the process of step S602.

[0266] <Process S602> In step S602, the pause control unit 63 derives the jib point position that changes due to the operation of the second winch 162, based on the boom angle detection value θ1 and the jib angle detection value θ2.

[0267] The process of step S602 is the same as the process of step S402 in Fig. 14. The jib point position includes information on the jib point height. Furthermore, the start control unit 62 executes the process of step S603.

[0268] <Process S603> In step S603, the pause control unit 63 derives a hook height H1, which is the position of the hook 30 in the up-down direction.

[0269] The pause control unit 63 derives the hook height H1 based on the boom angle detection value θ1, the jib angle detection value θ2, and the rope hanging length. At that time, the pause control unit 63 derives the hook height H1 using dimensional information of the boom 21 and the jib 22. The dimensional information of the boom 21 and the jib 22 is known information.

[0270] The pause control unit 63 further executes the process of step S604.

[0271] <Process S604> In step S604, the pause control unit 63 determines whether or not the hook height H1 is below a preset first allowable height H11.

[0272] The pause control unit 63 executes the process of step S605 when it determines that the hook height H1 falls below the first allowable height H11.

[0273] On the other hand, when the pause control unit 63 determines that the hook height H1 is not below the first allowable height H11, the pause control unit 63 ends the jib folding control. As a result, the pause control unit 63 shifts the process to step S501.

[0274] <Process S605> In step S605, the pause control unit 63 causes the third winch 163 to execute an operation of winding up the third rope 33.

[0275] For example, in step S605, the pause control unit 63 operates the third winch 163 at a predetermined speed. Also, in step S605, the pause control unit 63 may operate the third winch 163 at a speed according to the difference between the first allowable height H11 and the hook height H1.

[0276] In step S605, the pause control unit 63 may operate the third winch 163 for a period of time according to the difference between the first allowable height H11 and the hook height H1.

[0277] After executing the process of step S605, the pause control unit 63 ends the jib folding control, whereby the pause control unit 63 shifts the process to step S501.

[0278] The processing in steps S602 to S605 prevents the hook 30 from landing on the ground or approaching the upper rotating body 12 while the jib folding control is being executed.

[0279] [Second pause control] Next, an example of a procedure of the second pause control will be described with reference to the flowchart shown in FIG.

[0280] The pause control unit 63 executes the second pause control after the locked state of the latch device 8 is detected by the lock sensor 453 in a situation in which the pause mode is set.

[0281] In the following description, S701, S702, ... represent identification symbols of a plurality of steps in the second pause control. In the second pause control, the pause control unit 63 starts with the processing of step S701.

[0282] <Process S701> In step S701 and step S702 described later, the pause control unit 63 checks an operation on the operation device 5. The pause control unit 63 executes the process of step S703 when a predetermined second pause operation is being performed on the operation device 5.

[0283] For example, the second pause operation is an operation for one of the boom operation lever 511 and the jib operation lever 512. The second pause operation may be the same as the first pause operation.

[0284] For example, the second pause operation is a pushing operation on the boom operation lever 511. The pushing operation on the boom operation lever 511 is an operation on the boom operation lever 511 when an operation of paying out the first rope 31 is instructed in the normal mode.

[0285] Moreover, the second pause operation may be a pushing operation on the jib operation lever 512. The pushing operation on the jib operation lever 512 is an operation on the jib operation lever 512 when an operation of paying out the second rope 32 is instructed in the normal mode.

[0286] On the other hand, when the second pause operation on the operation device 5 is not performed, the pause control unit 63 executes the process of step S702.

[0287] <Process S702> In step S702, the pause control unit 63 checks whether or not an operation other than the second pause operation has been performed on the operation device 5. When an operation other than the second pause operation has been performed on the operation device 5, the pause control unit 63 executes the process of step S705.

[0288] On the other hand, when the second pause operation and other operations on the operation device 5 are not being performed, the pause control unit 63 shifts the process to step S701.

[0289] <Process S703> In step S703, the pause control unit 63 determines whether the boom angle detection value θ1 has reached or reached a preset target tilt angle θ12 or less. The boom angle detection value θ1 being less than or equal to the target tilt angle θ12 is an example of the boom angle detection value θ1 being within the target tilt range.

[0290] FIG. 6 shows an example of the lying down state, which is the state of the crane 10 when the detected jib angle value θ2 reaches the target tilt angle θ12 or less.

[0291] The pause control unit 63 executes the process of step S704 when it determines that the detected jib angle value θ2 has not reached the target tilt angle θ12 or less.

[0292] On the other hand, when the pause control unit 63 determines that the boom angle detection value θ1 has reached the target tilt angle θ12 or less, it executes the process of step S706.

[0293] The boom angle detection value θ1 reaching the target tilt angle θ12 or less is an example of the boom angle detection value θ1 reaching within a predetermined target tilt range.

[0294] <Process S704> In step S704, the pause control unit 63 executes boom tilting control, which will be described later (see FIG. 18). In the boom tilting control, the pause control unit 63 executes control for rotating the boom 21 from the upright state shown in FIG. 10 to the lying down state shown in FIG.

[0295] After executing the boom tilting control, the pause control unit 63 shifts the process to step S701. When the second pause operation is being performed on the operation device 5, the pause control unit 63 executes the boom tilting control until the boom angle detection value θ1 reaches or is equal to or smaller than the target tilt angle θ12 (step S704).

[0296] <Process S705> In step S705, the pause control unit 63 executes the normal control in response to an operation other than the second pause operation on the operation device 5. The processes in steps S702 and S705 are the same as the processes in steps S102 and S105 in FIG.

[0297] After executing the process of step S705, the pause control unit 63 shifts the process to step S701. For example, the pause control unit 63 executes the processes of steps S701 to S705 at a predetermined cycle.

[0298] <Process S706> In step S706, the pause control unit 63 executes the phase transition notification for notifying the operator that the boom angle detection value θ1 has reached the target tilt angle θ12 or less. The process of step S706 is similar to the process of step S106.

[0299] After executing the process of step S706, the pause control unit 63 ends the second pause control, whereby the pause control ends.

[0300] [Boom tilt control] Next, an example of a procedure for the boom tilting control will be described with reference to the flowchart shown in FIG.

[0301] In the following description, S801, S802, ... represent identification codes of a plurality of steps in the boom tilting control. In the boom tilting control, the pause control unit 63 starts with the processing of step S801.

[0302] <Process S801> In step S801, the pause control unit 63 causes the first winch 161 to execute the reeling out of the first rope 31. At that time, the pause control unit 63 operates the first winch 161 at a speed according to the displacement amount of the operating lever that is the target of the second pause operation.

[0303] In step S801, the pause control unit 63 may limit the acceleration of the payout of the first rope 31 by the first winch 161 to a range not exceeding a predetermined fourth upper limit acceleration. In this case, the pause control unit 63 accelerates the operation of the first winch 161 at the fourth upper limit acceleration when the acceleration of the displacement of the operating lever that is the target of the second pause operation exceeds a predetermined acceleration.

[0304] Furthermore, the pause control unit 63 executes the process of step S802.

[0305] <Process S802> In step S802 and in step S803 described later, the pause control unit 63 checks the jib tension detection value F2, which is the detection value of the jib tension sensor 452.

[0306] The pause control unit 63 executes the process of step S804 when the jib tension detection value F2 exceeds the predetermined allowable upper limit value F22. On the other hand, the pause control unit 63 executes the process of step S803 when the jib tension detection value F2 does not exceed the allowable upper limit value F22.

[0307] <Process S803> In step S803, the pause control unit 63 checks whether the jib tension detection value F2 is below a predetermined allowable lower limit value F21.

[0308] The range from the allowable lower limit value F21 to the allowable upper limit value F22 is the allowable range of the tension applied to the second rope 32.

[0309] The pause control unit 63 executes the process of step S805 when the jib tension detection value F2 is below the allowable lower limit value F21. On the other hand, the pause control unit 63 executes the process of step S806 when the jib tension detection value F2 is not below the allowable lower limit value F21.

[0310] <Process S804> In step S804, the pause control unit 63 causes the second winch 162 to execute the operation of reeling out the second rope 32. The process of step S804 is the same as the process of step S205 in FIG.

[0311] The processing of steps S802 and S804 prevents excessive tension from being applied to the second rope 32 in the process of lowering the boom 21. Here, the processing of steps S802 and S804 is executed only when the second pause operation is executed. That is, the processing of steps S802 and S804 is executed even if a plurality of operations are not executed simultaneously.

[0312] <Process S805> In step S805, the pause control unit 63 causes the second winch 162 to execute the winding operation of the second rope 32. The process of step S805 is the same as the process of step S204 in FIG.

[0313] Furthermore, the pause control unit 63 executes the process of step S806.

[0314] By executing the processes of steps S802 to S805, it is possible to prevent the second rope 32 from becoming loose and from being subjected to excessive tension while the boom tilting control is being executed.

[0315] Therefore, problems such as poor winding of the second rope 32 by the second winch 162 or breakage of the second rope 32 are avoided.

[0316] The process in step S805 is an exceptional process that is not usually executed when the tilt control is being performed.

[0317] By performing the processes of steps S802 to S805, it is possible to prevent the second rope 32 from becoming loose and from being subjected to excessive tension while the boom raising control is being executed.

[0318] Therefore, problems such as poor winding of the second rope 32 by the second winch 162 or breakage of the second rope 32 are avoided.

[0319] <Process S806> In step S806, the pause control unit 63 derives, based on the boom angle detection value θ1, the jib point position that changes due to the operation of the first winch 161. The process of step S806 is the same as the process of step S206 in FIG.

[0320] As described above, the process of deriving the jib point position includes the process of deriving the jib point height. Furthermore, the pause control unit 63 executes the process of step S807.

[0321] <Process S807> In step S807, the pause control unit 63 derives the hook height H1 based on the boom angle detection value θ1, the jib angle detection value θ2, and the rope hanging length. The process of step S807 is the same as the process of step S603 in FIG.

[0322] The pause control unit 63 further executes the process of step S808.

[0323] <Process S808> In step S808, the pause control unit 63 determines whether or not a predetermined landing condition is met.

[0324] The landing condition is a condition that indicates that the hook 30 lands by the payout of the third rope 33 by the third winch 163. For example, the hook 30 lands in a state in which the boom 21 is tilted from about 20 degrees to about 30 degrees.

[0325] For example, the landing condition may be a first landing condition or a second landing condition. Also, the landing condition may be a logical AND or a logical OR of the first landing condition and the second landing condition.

[0326] The first landing condition is a condition in which, under a situation in which the pause mode is set and the locked state is detected by the lock sensor 453, a pushing operation is performed on the suspension operation lever 513 when the second pause operation is not being performed.

[0327] The pushing operation on the operation lever 513 is an example of an operation for instructing the third winch 163 to pay out the third rope 33. The first landing condition is met when the pushing operation on the hoisting operation lever 513 is detected in step S702 of FIG.

[0328] The second landing condition is a condition that a predetermined confirmation operation is performed using the operation button 52 or the input device 53. The operator performs the confirmation operation when the hook 30 has landed.

[0329] On the other hand, if it is determined that the landing condition is not met, the pause control unit 63 executes the process of step S809.

[0330] On the other hand, when it is determined that the landing condition is satisfied, the pause control unit 63 ends the boom tilting control. As a result, the pause control unit 63 shifts the process to step S701 in FIG.

[0331] <Process S809> In step S809, the pause control unit 63 determines whether or not the hook height H1 is below a preset second allowable height H12.

[0332] The pause control unit 63 executes the process of step S810 when it determines that the hook height H1 is lower than the second allowable height H12.

[0333] On the other hand, when the pause control unit 63 determines that the hook height H1 is not below the second allowable height H12, the pause control unit 63 ends the boom tilting control. As a result, the pause control unit 63 shifts the process to step S701.

[0334] <Process S810> In step S810, the pause control unit 63 causes the third winch 163 to execute an operation of winding up the third rope 33.

[0335] For example, in step S810, the pause control unit 63 operates the third winch 163 at a predetermined speed. Also, in step S810, the pause control unit 63 may operate the third winch 163 at a speed according to the difference between the second allowable height H12 and the hook height H1.

[0336] Furthermore, in step S810, the pause control unit 63 may operate the third winch 163 for a period of time according to the difference between the second allowable height H12 and the hook height H1.

[0337] After executing the process of step S810, the pause control unit 63 ends the boom tilting control. As a result, the pause control unit 63 shifts the process to step S701.

[0338] The processing in steps S806 to S810 is for preventing the hook 30 from landing against the operator's will. The processing in steps S809 and S810 is for controlling the third winch 163 based on the hook height H1.

[0339] The pause control unit 63 executes the processes of steps S809 and S810 until the landing condition is satisfied. On the other hand, the pause control unit 63 does not execute the processes of steps S809 and S810 after the landing condition is satisfied.

[0340] In addition, the pause control unit 63 causes the notification unit to execute the phase transition notification when a predetermined notification condition is met while the pause mode is set (see step S506 in FIG. 15 and step S706 in FIG. 17).

[0341] The notification conditions include a fourth notification condition corresponding to step S506 and a fifth notification condition corresponding to step S706.

[0342] The fourth notification condition is a condition that the locked state is detected by the lock sensor 453 (see step S503 in FIG. 15).

[0343] The fifth notification condition is a condition that the boom angle detection value θ1 has reached a target tilt angle θ12 or less (see step S703 in FIG. 17).

[0344] By issuing the phase transition notification, the operator can recognize that there has been a change in the phase of control in the crane 10. Note that only one of the fourth notification condition and the fifth notification condition may be adopted as the notification condition.

[0345] [First application example] Next, a first application example of the crane 10 will be described with reference to FIG.

[0346] In this application example, the pause control unit 63 executes the jib folding control in the procedure shown in FIG. 18, instead of the jib folding control in the procedure shown in FIG.

[0347] Hereinafter, an example of the procedure for controlling the folding of the jib in this application example will be described with reference to the flowchart shown in FIG.

[0348] In the following description, S901, S902, ... represent identification codes of a plurality of steps in the jib folding control. In the jib folding control, the pause control unit 63 starts with the processing of step S901.

[0349] <Process S901> In step S901, the pause control unit 63 compares the rope hanging length L1 derived by the hanging length deriving unit 60 with a preset reference lower limit length L11.

[0350] The pause control unit 63 executes the process of step S903 when the rope hanging length L1 falls below the reference lower limit length L11. On the other hand, the pause control unit 63 executes the process of step S902 when the rope hanging length L1 does not fall below the reference lower limit length L11.

[0351] <Process S902> In step S902, the pause control unit 63 compares the rope hanging length L1 with a preset reference upper limit length L12.

[0352] The pause control unit 63 executes the process of step S904 when the rope hanging length L1 exceeds the reference upper limit length L12. On the other hand, the pause control unit 63 executes the process of step S905 when the rope hanging length L1 is within the range from the reference lower limit length L11 to the reference upper limit length L12.

[0353] The range from the reference lower limit length L11 to the reference upper limit length L12 represents the reference length range of the rope sagging length L1. The reference length range is the range of the rope sagging length L1 suitable for landing the hook 30 when the boom tilting control is performed.

[0354] <Process S903> In step S903, the pause control unit 63 causes the third winch 163 to execute an operation of paying out the third rope 33.

[0355] For example, in step S903, the pause control unit 63 operates the third winch 163 at a predetermined speed. Also, in step S903, the pause control unit 63 may operate the third winch 163 at a speed according to the difference between the reference lower limit length L11 and the rope hanging length L1.

[0356] In addition, in step S903, the start control unit 62 may operate the third winch 163 for a time period corresponding to the difference between the reference lower limit length L11 and the rope hanging length L1. The pause control unit 63 executes the process of step S905 following the process of step S903.

[0357] <Process S904> In step S904, the pause control unit 63 causes the third winch 163 to execute an operation of winding up the third rope 33.

[0358] For example, in step S904, the pause control unit 63 operates the third winch 163 at a predetermined speed. Also, in step S904, the pause control unit 63 may operate the third winch 163 at a speed according to the difference between the rope hanging length L1 and the reference upper limit length L12.

[0359] In addition, in step S904, the start control unit 62 may operate the third winch 163 for a time period corresponding to the difference between the rope hanging length L1 and the reference upper limit length L12. The pause control unit 63 executes the process of step S905 following the process of step S904.

[0360] <Process S905> In step S905, the pause control unit 63 causes the second winch 162 to execute the operation of reeling out the second rope 32. At that time, the pause control unit 63 operates the second winch 162 at a speed according to the displacement amount of the operating lever that is the target of the first pause operation.

[0361] After executing the process of step S905, the pause control unit 63 ends the jib folding control, whereby the pause control unit 63 shifts the process to step S501.

[0362] In this application example, when rope hanging length L1 is out of the reference length range, the pause control unit 63 executes the process of step S903 or step S904. In step S903 or step S904, the pause control unit 63 causes the third winch 163 to execute an operation of winding up the third rope 33 or an operation of letting out the third rope 33 so that the rope hanging length L1 falls within the reference length range.

[0363] By the processing of steps S901 to S904, the hook 30 is prevented from landing on the ground or approaching the upper rotating body 12 while the jib folding control is being executed.

[0364] Furthermore, by the processing of steps S901 to S904, it is possible to prevent the hook 30 from landing against the operator's will and the hook 30 from moving while in contact with the ground when the boom tilting control is being executed.

[0365] [Second application example] Next, a second application example of the crane 10 will be described.

[0366] In this application example, the start control unit 62 executes an operation restriction process for prohibiting the operation of the drive unit corresponding to a predetermined specific operation on the operation device 5 when the start mode is set.

[0367] Specifically, the start control unit 62 executes the operation restriction process in the first start control step S102 and the second start control step S302 (see FIGS. 11 and 13).

[0368] That is, when the start control unit 62 detects the specific operation on the operation device 5 in step S102, it skips the process of step S105. Similarly, when the start control unit 62 detects the specific operation on the operation device 5 in step S302, it skips the process of step S305.

[0369] Furthermore, the start control unit 62 may cause the display device 7 to display a predetermined error message when the specific operation is performed on the operation device 5 in a situation where the start mode is set.

[0370] For example, the specific operation includes one or both of a turning operation on a turning lever and a traveling operation on a traveling pedal. The turning lever and the traveling pedal are parts of the operating device 5.

[0371] The swing lever receives the swing operation that instructs the operation of a swing motor that swings the upper swing body 12. The travel pedal receives the travel operation that instructs the operation of the travel device 14. The swing motor is a part of the actuator 44.

[0372] When the normal mode is set, the normal control unit 61 operates the turning motor in response to the turning operation. Similarly, when the normal mode is set, the normal control unit 61 operates the traveling device 14 in response to the traveling operation.

[0373] In this application example, the pause control unit 63 may execute the operation restriction process when the pause mode is set.

[0374] Specifically, the pause control unit 63 executes the operation restriction process in the first pause control step S502 and the second pause control step S702 (see FIGS. 15 and 17).

[0375] By executing the operation restriction process, it is possible to prevent a drive unit that should not be operated from operating in the start mode or the pause mode, thereby improving the safety of the crane 10 when the start mode or the pause mode is set.

[0376] [Third application example] Next, a third application example of the crane 10 will be described.

[0377] In this application example, the processes of steps S108 and S110 in the first start control are omitted.

[0378] In this application example, the start control unit 62 executes the lock release control in step S107 (see FIG. 11). After that, the start control unit 62 stops outputting the lock release command to the latch device 8 when the release end condition is satisfied in the jib swing-out control.

[0379] [Fourth application example] Next, a fourth application example of the crane 10 will be described with reference to FIG.

[0380] In this application example, the control device 6 also operates as a discrimination unit 64 by the MPU 601 executing a predetermined calculation program (see FIG. 20).

[0381] The discrimination unit 64 derives the relative angle of the jib 22 with respect to the boom 21 based on the boom angle detection value θ1 and the jib angle detection value θ2. Furthermore, the discrimination unit 64 executes a lock discrimination process based on the detection result of the lock sensor 453 and the relative angle.

[0382] The lock determination process is a process for determining whether the lock state, the unlock state, or an abnormal state is a state in which at least one of the lock sensor 453, the boom angle meter 454, and the jib angle meter 455 may be abnormal.

[0383] Specifically, when the lock sensor 453 detects the locked state and the relative angle is below a predetermined reference angle, the discrimination unit 64 discriminates that the latch device 8 is in the locked state.

[0384] Moreover, when the lock sensor 453 does not detect the locked state, the determination unit 64 determines that the latch device 8 is in the unlocked state.

[0385] Furthermore, the discrimination unit 64 discriminates that the crane 10 is in the abnormal state when the lock sensor 453 detects the locked state and the relative angle exceeds the reference angle.

[0386] The lock sensor 453 detects, as the locked state, a state in which the engaging member 81 is engaged with the engaged member 83. The lock sensor 453 is provided in the latch device 8 and is an example of a detection sensor that detects the state of the latch device 8.

[0387] In this application example, the lock sensor 453 and the determination unit 64 are an example of a lock detection unit that detects the locked state.

[0388] Furthermore, when the determination unit 64 determines that the crane 10 is in the abnormal state, it outputs an abnormality notification via an information output device such as the display device 7.

[0389] Furthermore, when the discrimination unit 64 determines that the crane 10 is in the abnormal state while the start mode is set, the discrimination unit 64 cancels the setting of the start mode. For example, when canceling the setting of the start mode, the discrimination unit 64 changes the control mode from the start mode to the normal mode.

[0390] Furthermore, when the discrimination unit 64 determines that the crane 10 is in the abnormal state while the pause mode is set, the discrimination unit 64 cancels the setting of the pause mode. For example, when canceling the setting of the pause mode, the discrimination unit 64 changes the control mode from the pause mode to the normal mode.

[0391] If the setting of the start mode is released before the start control is started, the start control is not executed, and if the setting of the start mode is released while the start control is being executed, the start control is interrupted.

[0392] Similarly, if the pause mode is released before the pause control is started, the pause control is not executed, and if the pause mode is released while the pause control is being executed, the pause control is interrupted.

[0393] In this application example, the start control unit 62 and the pause control unit 63 use the determination result of the determination unit 64 as the detection result of the state of the latch device 8.

[0394] In addition, in the start mode, the discrimination unit 64 executes a jib state discrimination process after the start control unit 62 starts the jib swing-out control shown in FIG.

[0395] In the jib state determination process, the determination unit 64 determines whether the jib angle detection value θ2 satisfies the proper condition or not. For example, the determination unit 64 derives an allowable angle range, which is an allowable range of the change amount of the jib angle detection value θ2, every time the operation time of the second winch 162 reaches a predetermined reference time.

[0396] Furthermore, in the jib state discrimination process, the discrimination unit 64 discriminates whether the amount of change in the jib angle detection value θ2 each time the operation time of the second winch 162 reaches the reference time is within the allowable angle range or outside the allowable angle range.

[0397] The condition that the amount of change in the jib angle detection value θ2 each time the operation time of the second winch 162 reaches the reference time is within the permissible angle range is one example of the appropriate condition.

[0398] In addition, when the discrimination unit 64 determines in the jib state discrimination process that the amount of change in the jib angle detection value θ2 falls outside the allowable angle range, it outputs an abnormality notification via an information output device such as the display device 7.

[0399] Furthermore, when the discrimination unit 64 determines in the jib state discrimination process in the start mode that the change amount of the jib angle detection value θ2 is out of the allowable angle range, the discrimination unit 64 cancels the setting of the start mode. For example, when canceling the setting of the start mode, the discrimination unit 64 changes the control mode from the start mode to the normal mode.

[0400] The start control unit 62 continues the jib swinging control shown in FIG. 14 on the condition that it is determined that the amount of change in the jib angle detection value θ2 is within the allowable angle range.

[0401] On the other hand, when the setting of the start mode is released, the start control unit 62 suspends the jib swing-out control. That is, when it is determined that the amount of change in the jib angle detection value θ2 falls outside the allowable angle range, the start control unit 62 suspends the jib swing-out control.

[0402] In addition, in the pause mode, the discrimination unit 64 also executes the jib state discrimination process after the pause control unit 63 starts the jib folding control shown in FIG.

[0403] When the discrimination unit 64 determines that the amount of change in the jib angle detection value θ2 falls outside the allowable angle range in the jib state discrimination process in the pause mode, the discrimination unit 64 cancels the setting of the pause mode. For example, when canceling the setting of the pause mode, the discrimination unit 64 changes the control mode from the pause mode to the normal mode.

[0404] The pause control unit 63 continues the jib folding control shown in FIG. 16 on the condition that it is determined that the amount of change in the jib angle detection value θ2 is within the permissible angle range.

[0405] On the other hand, the pause control unit 63 suspends the jib folding control when the pause mode is released. That is, the pause control unit 63 suspends the jib folding control when it is determined that the amount of change in the jib angle detection value θ2 falls outside the allowable angle range.

[0406] If the start control or the pause control is executed under a condition in which an abnormality occurs in a device such as the lock sensor 453, an unintended dangerous situation may occur.

[0407] By adopting this application example, when an abnormality occurs in at least one of the lock sensor 453, the boom angle meter 454, and the jib angle meter 455, the start control is not executed or is interrupted. The same applies to the pause control.

[0408] Therefore, by adopting this application example, the occurrence of dangerous situations caused by abnormalities in the equipment can be avoided.

[0409] In addition, in this application example, the discrimination unit 64 may execute a boom state discrimination process similar to the jib state discrimination process in the start mode or the pause mode.

[0410] For example, in the boom state determination process, the determination unit 64 determines whether or not the boom angle detection value θ1 satisfies the appropriate condition, similarly to the jib state determination process.

[0411] Furthermore, when the discrimination unit 64 determines in the boom state discrimination process that the amount of change in the boom angle detection value θ1 is outside the allowable angle range, it outputs an abnormality notification via an information output device such as the display device 7.

[0412] Furthermore, when the determination unit 64 determines in the boom state determination process in the start mode that the amount of change in the boom angle detection value θ1 falls outside the allowable angle range, the determination unit 64 cancels the setting of the start mode.

[0413] Furthermore, when the determination unit 64 determines in the boom state determination process in the pause mode that the amount of change in the boom angle detection value θ1 falls outside the allowable angle range, it cancels the setting of the pause mode.

[0414] [Fifth application example] Next, a fifth application example of the crane 10 will be described.

[0415] In this application example, the control device 6 includes a determination unit 64 (see FIG. 20).

[0416] In this application example, the discrimination unit 64 derives the relative angle based on the boom angle detection value θ1 and the jib angle detection value θ2. Furthermore, the discrimination unit 64 discriminates the state of the latch device 8 based on the relative angle.

[0417] For example, when the relative angle is below a predetermined reference angle, the discrimination unit 64 determines that the latch device 8 is in the locked state. When the relative angle is above the reference angle, the discrimination unit 64 determines that the latch device 8 is in the unlocked state.

[0418] In this application example, the boom angle meter 454, the jib angle meter 455, and the discrimination unit 64 are an example of a lock detection unit that detects the locked state. In this case, the boom angle meter 454 serves both as the boom angle detection unit and the lock detection unit. Similarly, the jib angle meter 455 serves both as the jib angle detection unit and the lock detection unit.

[0419] By adopting this application example, it is possible to omit the lock sensor 453.

[0420] In this application example, the discrimination unit 64 may execute the jib state discrimination process in the start mode and the pause mode. Similarly, the discrimination unit 64 may execute the boom state discrimination process in the start mode and the pause mode. [Explanation of symbols]

[0421] 5: Operating device 6: Control device 7:Display device 8: Latch device (jibloc mechanism) 10: Crane 21: Boom 22: Jib 30: Hook 31: First Rope 32: Second Rope 33: Third Rope 161: First winch 162: 2nd winch 163: 3rd winch 511: Boom operation lever 512: Jib operation lever 513: Lifting operation lever

Claims

1. A crane control method for implementing control of a crane, comprising: The crane, A boom connected to the main body in a hoistable manner; A first rope connected to the boom; A first winch that changes an angle of the boom by winding up or unwinding the first rope; a boom angle detection unit that detects an angle of the boom; A jib rotatably connected to the tip of the boom; A second rope connected to the jib; A second winch that changes an angle of the jib with respect to the boom by winding or unwinding the second rope; A jib tension detection unit that detects a tension applied to the second rope; A jib lock mechanism that locks the jib to the boom when the jib is along the boom and can release the state in which the jib is locked to the boom; A lock detection unit that detects a locked state in which the jib lock mechanism locks the jib to the boom; A hook for suspending a load; A third rope connected to the hook and suspended from the tip of the jib; A third winch that changes the length of a portion of the third rope hanging down from the tip of the jib by winding up or unwinding the third rope; A jib angle detection unit that detects the angle of the jib; A hanging length measuring unit that measures a rope hanging length, which is the length of a portion of the third rope hanging from the tip of the jib; An operation unit that accepts operations by a person; and a control device for controlling the crane. The control device derives a hook height, which is a vertical position of the hook, based on the detection value of the boom angle detection unit, the detection value of the jib angle detection unit, and the rope sagging length; When a pause mode, which is one of a plurality of predetermined control modes, is set and a detection value of the boom angle detection unit is within a predetermined target raising range, and a predetermined first pause operation is being performed on the operation unit, the control device executes a jib folding control until the lock state is detected by the lock detection unit; when a predetermined second pause operation is being performed on the operation unit in a situation in which the pause mode is set after the locked state is detected by the lock detection unit, the control device executes boom tilt control until a detection value of the boom angle detection unit reaches within a predetermined target tilt range, The jib folding control includes: The control device causes the second winch to execute an operation of paying out the second rope; The control device causes the third winch to perform an operation of winding up the third rope when the hook height falls below a first allowable height that is set in advance, The boom tilting control is The control device causes the first winch to execute an operation of paying out the first rope; A crane control method comprising: the control device causing the second winch to execute an operation of paying out the second rope when the detection value of the jib tension detection unit exceeds an allowable range.

2. A crane control method for implementing control of a crane, comprising: The crane, A boom connected to the main body in a hoistable manner; A first rope connected to the boom; A first winch that changes an angle of the boom by winding up or unwinding the first rope; a boom angle detection unit that detects an angle of the boom; A jib rotatably connected to the tip of the boom; A second rope connected to the jib; A second winch that changes an angle of the jib with respect to the boom by winding or unwinding the second rope; A jib tension detection unit that detects a tension applied to the second rope; A jib lock mechanism that locks the jib to the boom when the jib is along the boom and can release the state in which the jib is locked to the boom; A lock detection unit that detects a locked state in which the jib lock mechanism locks the jib to the boom; A hook for suspending a load; A third rope connected to the hook and suspended from the tip of the jib; A third winch that changes the length of a portion of the third rope hanging down from the tip of the jib by winding up or unwinding the third rope; A hanging length measuring unit that measures a rope hanging length, which is the length of a portion of the third rope hanging from the tip of the jib; An operation unit that accepts operations by a person; and a control device for controlling the crane. When a pause mode, which is one of a plurality of predetermined control modes, is set and a detection value of the boom angle detection unit is within a predetermined target raising range, and a predetermined first pause operation is being performed on the operation unit, the control device executes a jib folding control until the lock state is detected by the lock detection unit; when a predetermined second pause operation is being performed on the operation unit in a situation in which the pause mode is set after the locked state is detected by the lock detection unit, the control device executes boom tilt control until a detection value of the boom angle detection unit reaches within a predetermined target tilt range, The jib folding control includes: The control device causes the second winch to execute an operation of paying out the second rope; the control device causes the third winch to execute an operation of winding up the third rope or an operation of letting out the third rope when the rope sagging length is out of a preset reference length range so that the rope sagging length falls within the reference length range, The boom tilting control is The control device causes the first winch to execute an operation of paying out the first rope; A crane control method comprising: the control device causing the second winch to execute an operation of paying out the second rope when the detection value of the jib tension detection unit exceeds an allowable range.

3. The crane, A jib angle detection unit that detects the angle of the jib; and a hanging length measuring unit for measuring a rope hanging length, which is the length of the portion of the third rope hanging from the tip of the jib. The control device derives a hook height, which is a vertical position of the hook, based on the detection value of the boom angle detection unit, the detection value of the jib angle detection unit, and the rope sagging length, The boom tilting control is 3. The crane control method according to claim 1, further comprising: causing the third winch to perform an operation of winding up the third rope when the hook height falls below a preset second allowable height.

4. 4. The crane control method according to claim 3, wherein, in the boom tilting control, the control device executes control of the third winch based on the hook height until a predetermined landing condition is satisfied, and does not execute control of the third winch based on the hook height after the landing condition is satisfied.

5. 5. The crane control method according to claim 4, wherein the landing condition includes a condition that, when the pause mode is set and the locked state is detected by the lock detection unit, an operation is performed to cause the third winch to perform an operation of paying out the third rope with respect to the operation unit when the second pause operation is not being performed.

6. The crane control method according to claim 4 , wherein the landing condition includes a condition that a predetermined confirmation operation is performed on the operation unit.

7. When the crane includes a notification unit that executes a notification process for a person operating the operation unit, The control device further includes causing the notification unit to execute the notification process when a notification condition is satisfied in a situation in which the sleep mode is set, The notification condition includes one or both of a fourth notification condition and a fifth notification condition, the fourth notification condition is a condition that the locked state is detected by the lock detection unit, 3. The crane control method according to claim 1, wherein the fifth notification condition is that a detection value of the boom angle detection unit has reached within the target tilt range.

8. When the operation unit includes a plurality of operation levers supported to be displaceable, the first pause operation and the second pause operation are each an operation on one of the plurality of operating levers, The control device, in the jib folding control, causes the second winch to execute an operation of paying out the second rope at a speed corresponding to the displacement amount of the operating lever, 3. The crane control method according to claim 1, further comprising: in the boom tilting control, the control device causes the first winch to execute an operation of paying out the first rope at a speed corresponding to a displacement amount of the operating lever.

9. The control device, in the jib folding control, limits the acceleration of the payout of the second rope by the second winch to a range not exceeding a predetermined third upper limit acceleration, 9. The crane control method according to claim 8, wherein the control device, in the boom tilting control, limits an acceleration of the payout of the first rope by the first winch to a range not exceeding a predetermined fourth upper limit acceleration.

10. The crane control method according to claim 1 or claim 2, further comprising: the control device determining whether or not the detection value of the jib angle detection unit satisfies an appropriate condition after starting the jib folding control; and interrupting the jib folding control when it determines that the detection value of the jib angle detection unit does not satisfy the appropriate condition.

11. The crane control method according to claim 10, further comprising canceling the setting of the pause mode when the control device determines that the detection value of the jib angle detection unit does not satisfy the proper condition.

12. The method for controlling a crane according to claim 8 , wherein the second pausing operation is the same operation as the first pausing operation.

13. A boom connected to the main body in a hoistable manner; A first rope connected to the boom; A first winch that changes an angle of the boom by winding up or unwinding the first rope; a boom angle detection unit that detects an angle of the boom; A jib rotatably connected to the tip of the boom; A second rope connected to the jib; A second winch that changes an angle of the jib with respect to the boom by winding or unwinding the second rope; A jib tension detection unit that detects a tension applied to the second rope; a jib lock mechanism including a mechanism for locking the jib to the boom in a state along the boom when the jib rotates to a position along the boom and a mechanism for releasing the state in which the jib is locked to the boom; A lock detection unit that detects a locked state in which the jib lock mechanism locks the jib to the boom; A hook for suspending a load; A third rope connected to the hook and suspended from the tip of the jib; A third winch that changes the length of a portion of the third rope hanging down from the tip of the jib by winding up or unwinding the third rope; An operation unit that accepts operations by a person; A crane comprising: a control device that realizes the crane control method according to claim 1 or 2.

14. The lock detection unit is A detection sensor provided in the jib lock mechanism and configured to detect a state of the jib lock mechanism; The crane according to claim 13, further comprising a discrimination unit that discriminates between the locked state, an unlocked state in which the jib is not locked to the boom, and an abnormal state based on the detection result of the detection sensor and a relative angle of the jib with respect to the boom based on the detection values ​​of the boom angle detection unit and the jib angle detection unit, respectively.

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