crane

Abstract

To provide a crane which can be easily operated according to an operator's intention.SOLUTION: There is provided a crane equipped with operation members (221a, 221) capable of performing at least one of accelerating operation for increasing / decreasing the rotation speed of an engine (107) and turning operation for a revolving body (103), in which a predetermined motion (swing motion, traveling motion, etc.) is stopped when the operator is not touching the operation member and the crane is performing the predetermined motion.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to a crane. [Background technology]

[0002] Generally, operating a crane is complicated and difficult because it requires multiple simultaneous operations such as winch lifting / lowering, rotation, boom raising / lowering, and traveling (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2016-102017 A Summary of the Invention [Problem to be solved by the invention]

[0004] Because operating a crane is thus complex and difficult, there is a demand for cranes that can be easily operated in accordance with the operator's intentions.

[0005] Therefore, an object of the present invention is to provide a crane that can be easily operated in accordance with the operator's intentions. [Means for solving the problem]

[0006] In order to achieve the above object, a representative embodiment of the present invention is a vehicle that can perform at least one of an accelerator operation for increasing or decreasing the rotation speed of an engine and a rotation operation of a rotating body. No. 1 A crane equipped with an operating member, A predetermined operation of the crane can be performed which is different from the operation operated by the first operating member, and a second operating member different from the first operating member is provided, and the second operating member can be locked in a predetermined operating position; The above No. 1 The operator is not touching the operating member, and Corresponding to the operation of the second operating member When the crane is performing a predetermined operation, of the crane corresponding to the operation of the second operating member It is characterized by stopping a predetermined operation.

[0007] In the present invention, the operating member includes not only a separate configuration in which a member for performing an accelerator operation and a member for performing a slewing operation are integrated, but also a configuration in which they are integrated. In addition, the predetermined operation of the crane includes, for example, the slewing operation of the slewing body, the traveling operation of the traveling body, and the rotation operation of the winch (the winding and unwinding of the rope). Therefore, the present invention includes, for example, stopping the slewing operation when the operator is not touching the operating member and the slewing operation of the crane is being performed. In addition, the present invention includes, for example, stopping the traveling operation when the operator is not touching the operating member and the traveling operation of the crane is being performed. In addition, the present invention includes, for example, stopping the slewing operation and the traveling operation of the crane when the operator is not touching the operating member and the slewing operation and the traveling operation of the crane are being performed.

[0008] According to the present invention, it is possible to provide a crane that allows an operator to more easily operate the crane in accordance with his / her intention. Problems, configurations, and effects other than those described above will become apparent from the following description of the embodiments. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a side view of a crane according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a perspective view showing the entire operator's cab. [Diagram 3] FIG. [Figure 4] FIG. 13 is a diagram showing the left lever (swivel lever). [Diagram 5] FIG. 4 is a hydraulic circuit diagram for driving a rotation hydraulic motor. [Figure 6] 10 is a flowchart showing a processing procedure for stop control of a crane. [Figure 7] 10 is a flowchart showing a processing procedure for stop control of a crane according to a second embodiment. [Figure 8] 13 is a flowchart showing a processing procedure for stop control of a crane according to a third embodiment. [Figure 9]13 is a flowchart showing a processing procedure for stop control of a crane according to a fourth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] (First embodiment) Hereinafter, an embodiment of a crane according to the present invention will be described with reference to the drawings.

[0011] 1 is a side view of a crane 100 according to an embodiment of the present invention. The crane 100 is a crawler crane, and has a running body 101, a rotating body 103 rotatably mounted on the running body via a slewing ring 102, and a boom 104 rotatably supported on the rotating body 103.

[0012] The rotating body 103 is provided with a driver's cab 109, and is equipped with an engine 107 as a prime mover, as well as a hoist drum 105 and a hoisting drum 106 as winch devices. A hoisting rope 105a is wound around the hoisting drum 105, and the hoisting rope 105a is wound or unwound by driving the hoisting drum 105, thereby raising or lowering the hook 110. A hoisting rope 106a is wound around the hoisting drum 106, and the hoisting rope 106a is wound or unwound by driving the hoisting drum 106, thereby raising or lowering the boom 104.

[0013] The rotating body 103 is driven to rotate by a rotating hydraulic motor 1 (see Figure 5) via the rotating ring 102, the hoisting drum 105 is driven by a hoisting hydraulic motor (not shown), and the hoisting drum 106 is driven by a hoisting hydraulic motor (not shown).

[0014] Fig. 2 is a perspective view showing the entire operator's cab 109, Fig. 3 is a view showing the right-side lever group 210, and Fig. 4 is a view showing the left-side lever (swivel lever) 221. As shown in Fig. 2, the operator's cab 109 is provided with an operator's seat 201 where an operator sits, a right-side lever group 210 that the operator sitting in the operator's seat 201 operates with his right hand, and a left-side lever (swivel lever) 221 that the operator sitting in the operator's seat 201 operates with his left hand. In addition, a display device 231 is provided to the left front of the operator's seat 201, which displays various information such as the operating status of the crane 100 and warnings.

[0015] On the floor of the operator's cab 109, there are provided a hoist drum brake pedal 251 for braking the hoist drum 105, a hoist drum brake pedal 252 for braking the hoist drum 106, an accelerator pedal 261 (operating member) for increasing or decreasing the rotational speed of the engine 107, and a swing brake pedal 262 for braking the swing body 103.

[0016] As shown in FIG. 3, the right lever group 210 includes a pair of travel levers, i.e., a travel lever 211L for driving the left crawler and a travel lever 211R for driving the right crawler, as well as a hoisting winch operation lever 213F and a hoisting winch operation lever 213B.

[0017] The travel levers 211L, 211R are control levers for driving the right and left crawlers, respectively, by swinging them forward and backward. The travel levers 211L, 211R have a mechanism for locking the operation position at the maximum operation position (operation amount). In other words, when the operator pushes the travel levers 211L, 211R to the maximum operation position, the crane 100 maintains traveling at a speed corresponding to the maximum operation position.

[0018] The hoisting winch operation lever 213F is an operation lever that is swung back and forth to drive the hoist drum 105. The hoisting winch operation lever 213B is an operation lever that is swung back and forth to drive the hoisting drum 106. The hoisting winch operation lever 213F and the hoisting winch operation lever 213B also have a mechanism (detent mechanism) that locks the operating position.

[0019] The left lever, i.e., the swing lever 221 (swing operation member / operation member), is an operation lever for swinging the swing body 103 in the front-rear direction. As shown in FIG. 4, the swing lever 221 has a grip 221d that is gripped by an operator seated in the driver's seat 201. The swing lever 221 is provided with an accelerator grip 221a (operation member), a swing brake switch 221b, and a touch sensor 221c. Note that the swing lever 221 in this embodiment does not have a mechanism for locking the operation position, but may have a mechanism for locking it at the maximum swing operation position, similar to the travel levers 211L, 211R and the winch operation levers 213F, 213B described above.

[0020] The accelerator grip 221a is an operating device for increasing or decreasing the rotation speed of the engine 107 by rotating it clockwise or counterclockwise when viewed from above while the operator holds it with his left hand. The accelerator grip 221a is integrated with the turning lever 221, so that the operator can operate the turning lever 221 while operating the accelerator grip 221a with one hand. Note that in this embodiment, the rotation speed of the engine 107 can be increased or decreased by operating the accelerator pedal 261 in addition to operating the accelerator grip 221a.

[0021] The swing brake switch 221b is a switch for selecting whether or not to apply a swing brake that holds the swing body 103 so as not to swing. The touch sensor 221c is a detection means for determining whether or not an operator is touching the swing lever 221. As will be described later, in this embodiment, the controller 3 (see FIG. 5) applies a brake to a predetermined operation of the crane 100 based on the presence or absence of an input of a detection signal from the touch sensor 221c.

[0022] 2, a gate lock lever 215 is provided in the operator's cab 109. The gate lock lever 215 can be operated in the vertical direction between an unlocked position where the entrance to the operator's cab 109 is blocked and a locked position where the entrance to the operator's cab 109 is opened. When the gate lock lever 215 is in the locked position, it disables all operations of the crane 100. In other words, when the gate lock lever 215 is in the locked position, all operations of the crane 100, such as lifting, traveling, and swinging, are disabled.

[0023] Next, a hydraulic drive circuit for driving the swing body 103 of the crane 100 will be described. Fig. 5 is a diagram showing a hydraulic circuit HC1 for driving the swing hydraulic motor 1. As shown in Fig. 5, the hydraulic circuit HC1 is a neutral free swing hydraulic circuit in which a swing hydraulic pump (hereinafter simply referred to as hydraulic pump 8) and a swing hydraulic motor (hereinafter simply referred to as hydraulic motor 1) are connected by a directional control valve 7.

[0024] The hydraulic circuit HC1 includes a variable displacement hydraulic pump 8 driven by an engine 107 (see FIG. 1), a hydraulic motor 1 rotated by pressure oil discharged from the hydraulic pump 8, a swing brake device 20 that brakes the rotation of the hydraulic motor 1, and a relief valve 9 that determines the maximum pressure of the pressure oil discharged from the hydraulic pump 8. The hydraulic circuit HC1 also includes a directional control valve 7 that controls the flow of pressure oil from the hydraulic pump 8 to the hydraulic motor 1, a pilot pump 12 driven by the engine 107, a swing lever device 6, and a relief valve 11 that determines the maximum pressure of the pilot pressure oil discharged from the pilot pump 12.

[0025] The swing lever device 6 includes a swing lever 221 (see FIG. 4) and pilot valves 6a, 6b connected to the pilot pump 12. The swing lever device 6 is a swing operation device that generates an operating pilot pressure for instructing the swing operation of the swing body 103 by the pilot valves 6a, 6b according to the operation direction and operation amount of the swing lever 221, and outputs it to the pilot pressure input parts 7a, 7b of the directional control valve 7, thereby performing the swing operation of the swing body 103.

[0026] Pipes 30a, 30b to which pressure oil discharged from a hydraulic pump 8 is supplied via a directional control valve 7 are connected to the hydraulic motor 1. The rotational force of the hydraulic motor 1 is transmitted to a slewing ring 102 (see FIG. 1) via a planetary reduction mechanism (not shown).

[0027] The directional control valve 7 is a control valve having a neutral free position (N), and is inserted in an oil passage between the hydraulic pump 8 and the hydraulic motor 1. The directional control valve 7 has a spool position controlled by operating pilot pressure (pressure of pilot pressure oil) generated by pilot valves 6a, 6b in response to the operation of a turning lever 221 provided in the operator's cab 109.

[0028] When the operator operates the swing lever 221 to the forward rotation side, the operating pilot pressure output from the pilot valve 6a acts on the pilot pressure input portion 7a of the directional control valve 7, and the directional control valve 7 switches to the forward rotation position (A). As a result, the pressure oil discharged from the hydraulic pump 8 is supplied to the hydraulic motor 1 via the pipe 30b, the hydraulic motor 1 rotates forward, and the swing body 103 swings in the forward direction (for example, swings left).

[0029] When the operator operates the swing lever 221 to the reverse side, the operating pilot pressure output from the pilot valve 6b acts on the pilot pressure input portion 7b of the directional control valve 7, and the directional control valve 7 switches to the reverse position (B). As a result, the pressure oil discharged from the hydraulic pump 8 is supplied to the hydraulic motor 1 via the pipe 30a, the hydraulic motor 1 rotates in the reverse direction, and the swing body 103 swings in the reverse direction (for example, swings to the right).

[0030] When the operator returns the swing lever 221 from the swing operation position to the neutral position, the directional control valve 7 switches to the neutral free position (N), and the pipelines 30a and 30b are connected, so that the hydraulic motor 1 is able to rotate by receiving an external force. Therefore, the swing body 103 is in a free state in which it can rotate by inertia. This state is also called neutral free. When the swing body 103 is in the neutral free state, the swing brake device 20 described later is activated to generate a braking force on the swing body 103, thereby stopping the swing of the swing body 103.

[0031] The swing brake device 20 comprises a hydraulic cylinder (hereinafter referred to as the brake release cylinder 2) having a pad 2p that is pressed against a swing brake disc (not shown) provided on the output shaft of the hydraulic motor 1, and a swing brake valve 13 that controls the flow of pressurized oil supplied from the pilot pump 12 to the brake release cylinder 2.

[0032] The swing brake device 20 is a so-called negative brake, and when the brake release cylinder 2 is connected to the tank, the pad 2p is pressed against a swing brake disc (not shown) by spring force, the swing brake is activated, and a braking force is generated on the swing structure 103. When a release pressure acts on the brake release cylinder 2, the swing brake device 20 is released. When the swing brake device 20 is released, a gap is formed between the swing brake disc (not shown) and the pad 2p, so no braking force is generated on the swing structure 103.

[0033] The swing brake valve 13 is provided between the pilot pump 12 and the brake release cylinder 2. The swing brake valve 13 is an electromagnetic switching valve that allows the flow of pressurized oil from the pilot pump 12 to the brake release cylinder 2 in the release position (C) and prohibits the flow of pressurized oil from the pilot pump 12 to the brake release cylinder 2 in the actuated position (D). When the swing brake valve 13 is switched to the actuated position (D), the brake release cylinder 2 and the tank are connected, and the pressure in the oil chamber of the brake release cylinder 2 becomes the tank pressure.

[0034] The hydraulic circuit HC1 includes a gate lock valve 10 provided between the pilot pump 12 and the pilot valves 6a, 6b. The gate lock valve 10 is an electromagnetic switching valve that allows the flow of pressure oil from the pilot pump 12 to the pilot valves 6a, 6b in the communicating position (E) and prohibits the flow of pressure oil from the pilot pump 12 to the pilot valves 6a, 6b in the shutoff position (F).

[0035] The pilot pump 12 is connected to the swing brake valve 13 via the gate lock valve 10. When the gate lock valve 10 is switched to the shutoff position (F), pressurized oil is not supplied to the brake release cylinder 2 even if the swing brake valve 13 is switched to the release position (C), so the swing brake device 20 is in an activated state (i.e., a state in which braking force is generated). In other words, when the gate lock valve 10 is switched to the shutoff position (F), the swing lever 221 cannot be operated. The swing brake device 20 is released when the gate lock valve 10 is switched to the communicating position (E) and the swing brake valve 13 is switched to the release position (C).

[0036] The crane 100 is equipped with a controller 3 that includes a processor having a CPU, ROM and RAM as memory devices, and other peripheral circuits. The controller 3 is a control device that controls each part of the crane 100 based on signals from various sensors.

[0037] The controller 3 is electrically connected to the swing brake valve 13 and the gate lock valve 10. The controller 3 is electrically connected to a swing brake switch 221b provided on the swing lever 221, and switches the swing brake valve 13 to a release position (C) or an actuated position (D) based on a signal from the swing brake switch 221b. The controller 3 also switches the gate lock valve 10 to a communication position (E) or a cut-off position (F) based on the operation of a gate lock lever 215 (see FIG. 2) provided in the driver's cab 109.

[0038] More specifically, when the swing brake switch 221b is operated to the OFF (closed) position, a current is supplied from the power supply (not shown) of the controller 3 to the solenoid of the swing brake valve 13, and the solenoid is excited, switching the swing brake valve 13 to the release position (C). When the swing brake switch 221b is operated to the ON (open) position, the supply of current from the power supply (not shown) of the controller 3 to the solenoid of the swing brake valve 13 is cut off, and the solenoid is demagnetized, switching the swing brake valve 13 to the actuated position (D) by the spring force.

[0039] When the gate lock lever 215 is operated to the unlocked position, a current is supplied from the power supply (not shown) of the controller 3 to the solenoid of the gate lock valve 10, and the solenoid is excited, switching the gate lock valve 10 to the communicating position (E). When the gate lock lever 215 is operated to the lock actuation position, the supply of current from the power supply (not shown) of the controller 3 to the solenoid of the gate lock valve 10 is cut off, and the solenoid is demagnetized (de-energized), switching the gate lock valve 10 to the blocking position (F) by the spring force.

[0040] Although not shown in FIG. 5, the gate lock valve 10 is also provided between the pilot pump 12 and the travel levers 211L, 211R, the hoisting winch operation lever 213F, and the hoisting winch operation lever 213B. Therefore, when the gate lock lever 215 is in the locking position, all operations of the crane 100, such as lifting, traveling, and swinging, are disabled. That is, in this embodiment, when the controller 3 switches the gate lock valve 10 to the shutoff position (F), all operations of the crane 100 are stopped. In this way, the gate lock valve 10 has a function of stopping operations of each actuator (hydraulic motor 1, hoisting hydraulic motor, hoisting hydraulic motor, traveling motor, etc.) that operates the crane 100, that is, a function of simultaneously stopping each operation of the crane 100.

[0041] Furthermore, in this embodiment, a touch sensor 221c provided on the rotation lever 221 is electrically connected to the controller 3. The controller 3 controls the crane 100 to stop a predetermined operation based on the presence or absence of a detection signal input from the touch sensor 221c.

[0042] The following describes the control for stopping the operation of the crane 100. Fig. 6 is a flowchart showing the processing procedure for controlling the stop of the crane 100 by the controller 3. The processing shown in Fig. 6 is started when the key switch of the engine 107 is turned ON, and is repeatedly executed at a predetermined cycle (for example, every several tens of milliseconds).

[0043] 6, the controller 3 constantly monitors the detection signal of the touch sensor 221c, and when the touch sensor 221c is OFF, that is, when there is no detection signal input from the touch sensor 221c (S1 / Yes), it determines that the operator is not touching the rotation lever 221, and starts a timer. Then, the controller 3 counts the duration T of the OFF state of the touch sensor 221c (S2).

[0044] Next, the controller 3 determines whether the duration T exceeds a threshold value T1. Here, the threshold value T1 is set arbitrarily in consideration of the operability of the crane 100. In this embodiment, the threshold value T1 is set to 5 seconds, for example.

[0045] When the controller 3 determines that the duration T exceeds the threshold value T1 (S3 / Yes), the controller 3 determines whether the swing brake device 20 is in operation (S4). Specifically, the controller 3 determines whether the swing brake valve 13 is in the operation position (D).

[0046] When the controller 3 determines that the swing brake device 20 is in operation (S4 / Yes), that is, when the swing brake valve 13 is in the release position (C), it issues an alarm (S5). Specifically, the controller 3 displays an alarm on the display device 231 and issues an alarm sound from the speaker. Then, the controller 3 switches the swing brake valve 13 to the operation position (D) (S6). In this way, the swing operation (predetermined operation) of the crane 100 stops.

[0047] If the touch sensor 221c is ON (S1 / No), the controller 3 resets the timer and ends the process (S7). Also, if the duration T does not exceed the threshold value T1 (S3 / No) and if the swing brake device 20 is not operating (S4 / No), the controller 3 ends the process.

[0048] As described above, according to this embodiment, when the operator is not touching the swing lever 221 and the crane 100 is in a swinging motion (when in a specific state), the swing operation is stopped, so that a crane can be provided that makes it easier for the operator to operate according to his or her intention. Moreover, when the operator is not touching the swing lever 221 for a predetermined time (5 seconds), the swing brake device 20 operates, so there is no decrease in work efficiency. In other words, this embodiment can achieve both good crane operation and improved work efficiency.

[0049] In addition, since an alarm is issued before the rotation operation stops (S5), the operator can be alerted to the need to stop, making it easier for the operator to perform operations in line with his or her intentions.

[0050] In addition, even if the operator momentarily releases the swing lever 221, if the operator grips the swing lever 221 before the predetermined time has elapsed, the timer is reset (processing of S1 / No→S7), so that an alarm is issued and the swing brake device 20 is not activated. Therefore, a decrease in work efficiency is prevented.

[0051] Furthermore, in this embodiment, since the hydraulic circuit is configured with a neutral free position, inertial operation can be used during a swing operation, and the operation can be performed without shock so as to prevent the swinging of the load and the load on the boom 104 from increasing. On the other hand, if the operator does not intend to use inertial operation using the neutral free position, that is, if the operator continues to not touch the swing lever 221, the swing brake device 20 will be activated (S6), making it easier to perform operations according to the operator's intentions.

[0052] Here, when the time during which the rotation lever 221 is not touched exceeds the threshold value T1 (S3 / Yes), instead of the controller 3 activating the rotation brake device 20 to stop the rotation operation, it is also possible to configure the controller 3 to monitor the state of the traveling motor, and if it determines that the traveling motor is operating, to brake the traveling motor to stop the traveling operation (predetermined operation) of the crane 100.

[0053] Specifically, in S4, the controller 3 determines whether the traveling motor is operating based on signals from a rotation speed sensor provided on the drive shaft of the traveling motor and a speed sensor of the crane 100. If the controller 3 determines in S4 that the traveling motor is operating, it issues an alarm (S5) and then controls the traveling motor to stop rotating in S6.

[0054] According to this configuration, when the rotation lever 221 is not being touched and the crane 100 is in a traveling operation (during a specified operation), the traveling operation is stopped. Therefore, a crane can be realized that makes it easier for the operator to operate in accordance with his or her intention, since the rotation lever 221 is not being touched and therefore there is no intention to operate the crane 100.

[0055] Furthermore, in this embodiment, the travel levers 211L, 211R are configured to be lockable at a predetermined operating position as described above, so travel operation is possible without continuing to hold the travel levers 211L, 211R, and in this state, for example, the travel operation can be stopped by releasing the swing lever 221 and not touching the swing lever 221. Therefore, a crane can be realized that makes it easier for the operator to operate according to his or her intention, that is, when the operator has no intention of operating the crane 100 because the swing lever 221 is not being touched.

[0056] Second embodiment Fig. 7 is a flowchart showing the procedure for controlling the stop of a crane according to the second embodiment. The second embodiment is characterized in that, as shown in Fig. 7, the controller 3 switches the gate lock valve 10 to the shutoff position (F) instead of the swing brake valve 13 (S6-1), thereby activating the swing brake device 20.

[0057] When the gate lock valve 10 is switched to the shutoff position (F) in S6-1, pressure oil is not supplied to the brake release cylinder 2, so that the swing brake device 20 is in an activated state (i.e., a state in which a braking force is generated). Even with this configuration, the same effects as those of the first embodiment can be achieved.

[0058] Furthermore, when the gate lock valve 10 is switched to the shutoff position (F), the travel levers 211L, 211R, the hoisting winch operation lever 213F, and the hoisting winch operation lever 213B are also disabled at the same time. Therefore, even if a travel operation (second specified operation) or a winch rotation operation is being performed during a swing operation (first specified operation), these operations are stopped in parallel, and each operation stops approximately simultaneously. Therefore, according to the second embodiment, higher operability can be achieved.

[0059] Incidentally, instead of switching the gate lock valve 10 to the shutoff position (F), a configuration may be adopted in which the travel motor and the winch drive motor are each braked.

[0060] Third embodiment FIG. 8 is a flowchart showing the procedure of the stop control of the crane according to the third embodiment. In the third embodiment, as shown in FIG. 8, the controller 3 judges whether or not the winch device (hoisting drum 105, hoisting drum 106) is in operation (S8-1). Specifically, the controller 3 judges whether or not the hoisting winch operation lever 213F or the hoisting winch operation lever 213B is being operated. Then, if the winch device is in operation (S8-1 / Yes), the controller 3 stops the operation of the winch device before switching the swing brake valve 13 (S8-2). That is, the controller 3 stops the rotation drive of the hydraulic motor that rotates the hoisting drum 105 or the hoisting drum 106.

[0061] Even with this configuration, it is possible to achieve the same operational effects as in the first embodiment. In addition, since the stop control of the lifting operation is performed before the stop control of the revolving operation is performed, the revolving operation can be stopped more smoothly, and better operability can be achieved.

[0062] (Fourth embodiment) Fig. 9 is a flowchart showing the procedure for controlling the stop of a crane according to the fourth embodiment. The flowchart shown in Fig. 9 is for realizing control that does not immediately stop the operation of the crane when an alarm is issued contrary to the operator's intention.

[0063] 9, when an alarm is issued (S5), a timer is activated and starts counting the alarm time X (S9-1). If the alarm time X exceeds a threshold value X1 (e.g., 5 seconds), the controller 3 switches the swing brake valve 13 to the actuated position (D) to stop the swing operation (S6). On the other hand, if the alarm time X is equal to or less than the threshold value X1 (predetermined time), the controller 3 ends the process.

[0064] According to this configuration, if the operator operates the swing lever 221 again within the threshold value X1 after the alarm is issued, the determination in S1 becomes No in the next process of this flowchart, the timer is reset (S7), and the issuance of the alarm is stopped. As a result, the swing brake valve 13 is not switched to the operating position (D), and the swing operation of the crane 100 is maintained (returned).

[0065] According to this configuration, for example, if an alarm is issued because the operator accidentally releases the turning lever 221, the turning operation can be continued if the operator immediately touches the turning lever 221, so that a good turning operation can be realized. Note that the threshold value X1 (predetermined time) is not limited to 5 seconds. The threshold value X1 is appropriately determined in consideration of operability.

[0066] Reference to other embodiments The present invention is not limited to the above-described embodiment, and various modifications are possible without departing from the gist of the present invention, and all technical matters included in the technical ideas described in the claims are the subject of the present invention. The above-described embodiment shows a preferred example, but a person skilled in the art can realize various alternatives, modifications, variations, or improvements from the contents disclosed in this specification, and these are included in the technical scope described in the attached claims.

[0067] For example, in each of the above-described embodiments, an example has been described in which the touch sensor 221c is used to detect a state in which the operator is not touching the rotation lever 221, but the present invention is not limited to a configuration in which the touch sensor 221c is used. For example, instead of the touch sensor 221c, any means such as a limit switch, an optical sensor, or a camera may be used to detect a state in which the operator is not touching the rotation lever 221.

[0068] Also, since the operation of the swing lever 221 is usually frequent in the operation of a crane, in each of the above-described embodiments, the predetermined operation of the crane 100 (such as the swing operation) is stopped by detecting whether the touch sensor 221c is OFF (processing of S1). However, instead of this configuration, for example, it is also possible to detect whether the operator is touching the accelerator grip 221a or the accelerator pedal 261 (operating member), which are also frequently operated, and stop the predetermined operation of the crane 100. Also, instead of this, it is also possible to detect whether the operator is touching the travel levers 211L, 211R and stop the predetermined operation of the crane 100.

[0069] In addition, although the configuration (see FIG. 8) has been exemplified in which the suspension operation is stopped before the suspension control of the swing operation is performed, when the swing operation and the traveling operation are being performed, the traveling operation may be stopped before the suspension control of the swing operation is performed.In addition, when the swing operation, the suspension operation, and the traveling operation are being performed simultaneously, the suspension operation and the traveling operation may be performed before the swing operation.

[0070] In this embodiment, an example has been shown in which the traveling operation is stopped when the operator is not touching the swing lever 221 and the crane 100 is in a traveling operation (predetermined operation), and an example has been shown in which the swing operation is stopped when the operator is not touching the swing lever 221 and the crane 100 is in a swing operation (specific state), but the crane 100 may be equipped with both of these two stop controls, or with only one of them. Also, the predetermined operation of the crane may be an operation other than the traveling or swing operation.

[0071] Furthermore, although a crawler crane has been given as an example of a crane, the present invention is not limited to this and can be applied to any type of cranes, including other mobile cranes such as wheel cranes, truck cranes, rough terrain cranes, all-terrain cranes, as well as tower cranes, overhead cranes, jib cranes, retractable cranes, stacker cranes, gantry cranes, unloaders, earth drills, and other foundation machines. [Explanation of symbols]

[0072] 1. Hydraulic motor for rotation 3. Controller 6 Swivel lever device 6a, 6b Pilot valve 7. Directional Control Valve 8. Swing hydraulic pump 10 Gate lock valve (stop member) 12 Pilot pump 13 Swing brake valve 20 Swing brake device 100 Crane 101 Vehicle 102 Swivel wheel 103 Rotating body 104 Boom 105 Hoisting drum (winch device) 106 Hoisting drum (winch device) 107 Engine 109 Driver's cab 110 Hook 211L Travel lever 211R Travel lever 213F Hoisting winch operation lever 213B Hoisting winch operation lever 215 Gate lock lever 221 Swivel lever (swivel operation part / operation part) 221a Accelerator grip (operating part) 221b Swing brake switch 221c Touch Sensor 221d Grip 231 Display device 251 Winding drum brake pedal 252 Drum brake pedal 261 Accelerator pedal (operating member) 262 Swivel brake pedal

Claims

1. A crane having a first operating member capable of performing at least one of an accelerator operation for increasing or decreasing the rotation speed of an engine and a rotation operation of a rotating body, A second operating member capable of operating a predetermined operation of the crane different from the operation operated by the first operating member and different from the first operating member, The second operating member is lockable at a predetermined operating position, A crane characterized in that, when an operator is not touching the first operating member and a predetermined operation of the crane corresponding to the operation of the second operating member is being performed, the predetermined operation of the crane corresponding to the operation of the second operating member is stopped.

2. 2. The crane of claim 1, the first operating member is a turning operating member capable of performing at least the turning operation, A crane characterized in that, when an operator is not touching the rotation operation member and a traveling operation is being performed as a predetermined operation of the crane, the traveling operation is stopped.

3. The crane according to claim 1 or 2, the first operating member is a turning operating member capable of performing at least the turning operation, When the rotation operation member is in a neutral position, the rotation body is configured to be rotatable by inertia, A crane characterized in that a rotation operation is stopped when the rotation operation member is in the neutral position and the operator is not touching the rotation operation member, and when a rotation operation is being performed as a predetermined operation of the crane.

4. 2. The crane of claim 1, There are a plurality of types of predetermined operations of the crane, A crane characterized in that, in a specific state in which an operator is not touching the first operating member and a first predetermined operation of the crane corresponding to operation of the second operating member is being performed, the first predetermined operation is stopped and a second predetermined operation of the crane corresponding to operation of the second operating member is also stopped.

5. 5. The crane according to claim 4, A crane, characterized in that the first predetermined motion is a rotation motion of the crane, and the second predetermined motion is a traveling motion of the crane.

6. A crane according to claim 4 or 5, A stop member is provided for stopping the operation of each actuator that operates the crane, A crane characterized in that, in the case of the specific state, the stopping member is activated to perform stop control of the first specified operation in parallel with stop control of the operation of the crane including the second specified operation.

7. 5. The crane according to claim 4, The crane is characterized in that, when the specific state is present, stop control of the second predetermined operation is started prior to stop control of the first predetermined operation.

8. 8. The crane according to claim 7, A crane, characterized in that the first predetermined motion is a rotation motion of the crane, and the second predetermined motion is a rotation motion of a winch of the crane.

9. The crane according to any one of claims 1 to 3, When the operator is not touching the first operating member and a predetermined operation of the crane is being performed, an alarm is issued, and the predetermined operation of the crane is stopped after the predetermined operation of the crane is performed for a predetermined time, A crane characterized in that, if the operator touches the first operating member within the predetermined time, the predetermined operation of the crane continues.

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