JP4486466B2 - Construction machine operation function monitoring device - Google Patents

Description

  The present invention relates to an operation function monitoring device for a construction machine that is provided in a construction machine such as a hydraulic excavator and can monitor an operation function of an electromagnetic valve included in a lock lever device.

  The lock lever device provided in the construction machine is disposed in the vicinity of the driver's seat, and the lock lever is operated so as to be in the lock position when the operator leaves the driver's seat. When the lock lever is operated to the lock position in this way, the operation signal for switching the direction switching valve that controls each hydraulic actuator is not output, that is, the output of the operation signal is not permitted, and the operation of the hydraulic actuator, Unintentional driving of the work member driven by the hydraulic actuator is prevented.

  Japanese Patent Application Laid-Open No. 2004-133867 discloses a conventional technique including such a lock lever device. This prior art is provided in a hydraulic excavator and includes an engine, that is, a prime mover, a hydraulic actuator, and a directional control valve, that is, a flow rate adjusting valve that controls inflow and outflow of pressure oil to the hydraulic actuator. Further, as a lock lever device, an electromagnetic valve for switching operation permission / non-permission of an operation signal for switching the flow rate adjusting valve, that is, a lock solenoid, a lock lever for switching the lock solenoid, and a lock lever Operation detecting means for detecting operation, that is, a switch, and a controller for outputting a drive control signal for driving the engine and for outputting a switching control signal for switching the lock solenoid in accordance with a signal output from the switch.

  In this prior art, when the lock lever is held in the free position, no signal is output from the above-mentioned switch to the controller, whereby a switching control signal for opening the lock solenoid is output from the controller to the lock solenoid. Then, an operation signal is output to the flow rate adjusting valve via the lock solenoid in the open position, and the flow rate adjusting valve is switched. Accordingly, pressure oil is supplied from the flow rate adjusting valve to the hydraulic actuator, the hydraulic actuator is operated, and the operating member can be driven by the hydraulic actuator.

  When the lock lever is switched to the lock position, a signal is output from the above-described switch to the controller, whereby the controller controls the lock solenoid to be in the closed position, and the flow regulating valve is controlled by the lock solenoid in the closed position. It becomes impossible to output an operation signal. That is, switching operation of the flow rate adjustment valve is not permitted. Therefore, in this state, the supply of pressure oil from the flow rate adjusting valve to the hydraulic actuator becomes impossible, that is, the hydraulic actuator becomes inoperable and the operating member is held so as not to move.

Thus, in the prior art, by providing the lock lever device, unintentional driving of the work member can be prevented, and safety protection for people and objects existing around the hydraulic excavator can be realized.
JP 2002-115277 A

  By the way, the construction machine provided with the lock lever device as described above is sometimes forced to be driven under a severe working environment. Under such a harsh working environment, dust or the like may enter the lock solenoid, that is, the solenoid valve, and the solenoid valve spool may stick and become unable to slide. When a stick is generated in the electromagnetic valve in this way, the operation of various devices, members, or hydraulic actuators included in the hydraulic circuit changes, but in the prior art, it takes time to understand the cause. There is a concern that it will take time to repair the hydraulic circuit.

  The present invention has been made from the actual situation in the above-described prior art, and an object thereof is to provide an operation function monitoring device for a construction machine that can immediately know that an abnormality has occurred in an electromagnetic valve included in a lock lever device. There is.

  In order to achieve the above object, the present invention provides a prime mover, a main hydraulic pump driven by the prime mover, a hydraulic actuator driven by pressure oil discharged from the main hydraulic pump, and a pressure applied to the hydraulic actuator. A solenoid valve that controls the output of an operation signal for switching the direction control valve, a lock lever that switches the solenoid valve, and a lock lever. An operation detecting means for detecting the operation of the lock lever; and a controller for outputting a drive control signal for driving the prime mover and for outputting a switching control signal for switching the electromagnetic valve in accordance with a signal output from the operation detecting means. It is provided in a construction machine having a lock lever device including a detection signal for permitting the output of the operation signal output from the solenoid valve. The controller detects whether the prime mover is being driven, and determines whether the lock lever is held so that the operation of the solenoid valve is not permitted. Further, determination means for determining whether or not the permission signal is detected by the permission detection means, and the determination means determines that the prime mover is being driven, and disables the output of the operation signal to the solenoid valve. As described above, when it is determined that the lock lever is held and it is further determined that the permission signal is detected by the permission detection means, a process for outputting a notification signal indicating that the solenoid valve is abnormal is performed. And an operation function of the electromagnetic valve of the lock lever device is monitored.

  For example, if a stick is generated while the prime mover is operating while the prime mover is being driven, the lock lever may be switched so that the solenoid valve is not allowed to output an operation signal, that is, the solenoid valve is closed. Since the electromagnetic valve remains open, a permission signal that enables control of the direction control valve is output from the electromagnetic valve.

  When such a situation occurs, the present invention determines that the determination unit of the controller determines that the prime mover is driving based on a drive control signal for driving the prime mover, and based on a signal output from the operation detection unit, It is determined that the lock lever is held so as to disallow the output of the operation signal to the solenoid valve, that is, it is determined that the lock lever is held at the lock position, and the signal output from the permission detection means Based on this, it is determined that a permission signal has been detected, and a notification signal is output from the processing means. It can be immediately known that an abnormality has occurred in the solenoid valve by this notification signal.

  Further, the present invention is characterized in that, in the above invention, the controller performs a process of stopping the prime mover in response to the notification signal output from the processing means.

  In addition, the present invention includes a hydraulic pilot pump that is driven by the prime mover and communicates with the electromagnetic valve, and the operation device that outputs the operation signal includes a hydraulic pilot valve, and the electromagnetic valve is switched to an open position. Sometimes the permission signal output from the solenoid valve to the operating device is the primary pressure discharged from the hydraulic pilot pump, and the permission detection means detects the primary pressure output from the solenoid valve. It is characterized by comprising a detection sensor.

  Further, according to the present invention, the construction machine includes a plurality of operation devices that output each of the operation signals and a hydraulic valve that switches between permitting and disapproving the output of the operation signals from these operation devices. It consists of an excavator.

  According to the present invention, it is possible to detect that an abnormality has occurred in the electromagnetic valve by the determination means of the controller, and in response to this detection, a notification signal is output from the processing means of the controller. This makes it possible to immediately know that the time required for repairing the hydraulic circuit including the solenoid valve can be reduced, and further safety protection for the surroundings of the construction machine can be realized.

  Hereinafter, the best mode for carrying out the operation function monitoring apparatus for construction machine according to the present invention will be described with reference to the drawings.

  FIG. 1 is a side view showing a hydraulic excavator cited as an example of a construction machine provided with an embodiment of an operation function monitoring apparatus according to the present invention.

  The hydraulic excavator includes a traveling body 31, a revolving body 32 disposed on the traveling body 31, a boom 33 connected to the revolving body 32 so as to be rotatable in the vertical direction, and a boom for driving the boom 33. A cylinder 34, an arm 35 coupled to the boom 33 so as to be pivotable in the vertical direction, an arm cylinder 36 for driving the arm 35, a bucket 37 coupled to the arm 35 so as to be pivotable in the vertical direction, And a bucket cylinder 38 for driving the bucket 37. Each of the boom 33, the arm 35, and the bucket 37 constitutes a working member, and the working member, the boom cylinder 34, the arm cylinder 36, and the bucket cylinder 38 constitute a front working machine that performs soil excavation work and the like. Has been.

  A driver's cab 39 is provided at the front position of the revolving structure 32, and a lock lever included in a lock lever device described later is disposed at a position near the driver's seat in the driver's cab 39.

  FIG. 2 is a hydraulic circuit diagram showing an embodiment of the present invention. As shown in FIG. 2, the hydraulic excavator shown in FIG. 1 includes a prime mover, that is, an engine 1, a main hydraulic pump 6 and a hydraulic pilot pump 10 driven by the engine 1, and the boom cylinder 34 and arm cylinder 36 described above. A plurality of directional control valves for controlling the inflow and outflow of pressure oil to the hydraulic actuator such as the bucket cylinder 38 are provided. In FIG. 2, only one hydraulic actuator, for example, a boom cylinder 34, and a boom direction control valve 8 for controlling inflow and outflow of pressure oil to the boom cylinder 34 are shown for easy understanding. The hydraulic actuator and the directional control valve are not shown. The boom direction control valve 8 includes pilot chambers 8a and 8b to which operation signals described later are given.

  In addition, an operation device that outputs an operation signal for switching the boom direction control valve 8 described above, for example, a hydraulic pilot valve 11 that outputs a pilot pressure signal as the operation signal is provided. The hydraulic pilot valve 11 includes pressure reducing valves 11a and 11b and an operation lever 11c for operating the pressure reducing valves 11a and 11b. The pressure reducing valve 11a of the hydraulic pilot valve 11 and the pilot chamber 8a of the direction control valve 8 are connected by a pilot line 14a, and the pressure reducing valve 11b and the pilot chamber 8b of the direction control valve 8 are connected by a pilot line 14b. ing.

  In FIG. 2, only the hydraulic pilot valve 11 constituting the boom operation device is illustrated, and other operation devices for arms, buckets, and the like are not shown.

  In the pipeline 13 connecting the hydraulic pilot pump 10 and the hydraulic pilot valve 11, an open position d where the pipeline 13 is communicated, and a closed position where the pipeline 13 is shut off and the hydraulic pilot valve 11 is communicated with the tank. An electromagnetic valve 15 having a position c is arranged. Further, as described above, the lock lever 3 is provided in the vicinity of the driver's seat and operates to switch the electromagnetic valve 15. Further, an operation detecting means for detecting the operation of the lock lever 3, that is, a switch 4 and a drive control signal for driving the engine 1 are output to the fuel supply control means 20 and switched according to a signal output from the switch 4. And a controller 2 that outputs a control signal to the electromagnetic valve 15.

  The electromagnetic valve 15, the lock lever 3, the switch 4, and the controller 2 constitute a lock lever device.

  Each of the plurality of hydraulic pilot valves including the hydraulic pilot valve 11 constituting the boom operating device is connected to one electromagnetic valve 15 via a pipe line 13.

  One embodiment of the operation function monitoring device for monitoring the operation function of the electromagnetic valve 15 provided in the hydraulic excavator configured as described above is output from the electromagnetic valve 15 and permits the output of the above-described operation signal, that is, the pilot pressure signal. Permission detection means for detecting a permission signal, that is, permission detection means for detecting the primary pressure discharged from the hydraulic pilot pump 10, for example, a detection switch 4 is provided.

  This embodiment is also included in the controller 2 to determine whether the engine 1 is being driven and to lock the electromagnetic valve 15 so that the pilot pressure signal output from the hydraulic pilot valve 11 or the like is not permitted. Is determined to be held in the locked position, and further, a determination unit that determines whether a permission signal is detected by a signal from the hydraulic pressure detection sensor 5, and the determination unit determines that the engine 1 is being driven, It is determined that the lock lever 3 is held in the locked position so that the solenoid valve 15 is not allowed to output the pilot pressure signal, and the permit signal, that is, the hydraulic pilot pump 10 discharges the signal from the hydraulic pressure detection sensor 5. And a processing means for performing a process of outputting a notification signal when it is determined that the primary pressure is detected.

  Moreover, the controller 2 performs the process which stops the engine 1, for example according to the above-mentioned report signal output from the above-mentioned processing means. That is, processing for stopping the output of a control signal for operating the fuel supply control means 20 is performed.

  Hereinafter, the operation of the present embodiment configured as described above will be described. FIG. 3 is a flowchart for explaining the operation of the main part in one embodiment of the present invention.

  As shown in step S1 of FIG. 3, first, it is determined by the determination means included in the controller 2 whether or not the engine 1 is operating, that is, whether or not it is being driven. This determination is made, for example, by checking whether or not a control signal for operating the fuel supply control means 20 is output from the controller 2. If it is confirmed that the control signal for operating the fuel supply control means 20 is not output from the controller 2, the engine 1 is in a stopped state and this determination is no, and the determination in step S1 is repeated. If it is confirmed that the control signal for operating the fuel supply control means 20 is output from the controller 2, the engine 1 is in operation, and the determination in step S1 is YES and the process proceeds to step S2.

  In this procedure S2, it is determined by the determination means included in the controller 2 whether the lock lever 3 is in the locked position and the detection switch 4 is on. That is, it is determined whether or not the lock lever 3 is held at the lock position so that the solenoid valve 15 is in the closed position c where the output of the pilot pressure signal from the hydraulic pilot valve 11 or the like to the direction control valve 8 or the like is not permitted. Is done. When the lock lever 3 is in the free position and the detection switch 4 is off, this determination is no and the process moves to step S6.

  In this procedure S6, a switching control signal is output from the controller 2 to the controller of the electromagnetic valve 15, whereby the electromagnetic valve 15 is switched to the open position d. Since the main hydraulic pump 6 and the hydraulic pilot pump 10 are now driven by driving the engine 1, the primary pressure from the hydraulic pilot pump 10, that is, the pilot pressure, is switched by switching the solenoid valve 15 to the open position d. Is supplied to all the hydraulic pilot valves including the hydraulic pilot valve 11 through the electromagnetic valve 15 and the pipe line 13.

  Therefore, for example, when the operation lever 11c of the hydraulic pilot valve 11 is rotated to the right in FIG. 2, the pilot pressure signal from the pressure reducing valve 11a is supplied to the pilot chamber 8a of the direction control valve 8 through the pilot line 14a. The As a result, the directional control valve 8 is switched from the neutral position N to the X position, and the pressure oil of the main hydraulic pump 6 is supplied to the bottom side of the boom cylinder 34 via the main conduit 9 and the directional control valve 8. The boom 33 shown in FIG. 1 is rotated upward. That is, a boom raising operation is performed.

  Further, for example, when the operation lever 11c of the hydraulic pilot valve 11 is rotated to the left in FIG. 2, the pilot pressure signal from the pressure reducing valve 11b is transferred to the pilot chamber 8b of the direction control valve 8 through the pilot line 14b. Supplied. As a result, the directional control valve 8 is switched to the Y position, the pressure oil of the main hydraulic pump 6 is supplied to the rod side of the boom cylinder 34 via the main conduit 9 and the directional control valve 8, and the boom cylinder 34 contracts. The boom 33 is rotated downward. That is, a boom lowering operation is performed.

  If it is determined in step S2 described above by the determination means of the controller 2 that the lock lever 3 is in the locked position and the detection switch 4 is on, this determination is yes and the process proceeds to step S3.

  In this procedure S3, the solenoid valve 15 is switched to the closed position c by the switching control signal output from the controller 2 to the control unit of the solenoid valve 15. By switching to the closed position c, the primary pressure from the hydraulic pilot pump 10 is not supplied to all the hydraulic pilot valves including the hydraulic pilot valve 11. That is, the output of the pilot pressure signal from each of all the hydraulic pilot valves including the hydraulic pilot valve 11 to the corresponding directional control valve 8 or the like is blocked, and the switching operation of all the directional control valves including the directional control valve 8 is disabled. It becomes permission.

  Therefore, in this state, the supply of pressure oil from the directional control valve 8 or the like to the corresponding hydraulic actuator such as the boom cylinder 34 becomes impossible, that is, which hydraulic pressure among all the hydraulic pilot valves including the hydraulic pilot valve 11 and the like. Even if the pilot valve is operated, the hydraulic actuator such as the boom cylinder 34 becomes inoperable, and the front working machine including the working member such as the boom 33, the turning body, or the traveling body is held so as not to move. As a result, unintentional driving of the front working machine including the working member such as the boom 33, the turning body, or the traveling body can be prevented, and safety protection for people and objects existing around the hydraulic excavator can be realized.

  After step S3 described above, the process proceeds to step S4. In this procedure S4, a determination signal included in the controller 2 detects a permission signal that permits the output of the pilot pressure signal to the directional control valve 8 or the like even though the electromagnetic valve 15 is switched to the closed position c. Whether the primary pressure from the hydraulic pilot pump 10 is supplied to the pipe line 13 is determined by a signal from the hydraulic pressure detection sensor 5. If this determination is NO, the hydraulic pressure detection sensor 5 detects that the primary pressure is not supplied from the solenoid valve 15 to the hydraulic pilot valve 11 and the like by switching the solenoid valve 15 to the closed position c. Is confirmed to function normally. Therefore, after the determination in step S4, the process returns to step S1.

  If the determination in step S4 is yes, a stick is generated in the solenoid valve 15, and the solenoid valve 15 that should have been closed remains open, and the primary pressure is applied from the solenoid valve 15 to the hydraulic pilot valve 11 and the like. Is detected by the oil pressure detection sensor 5, and it is confirmed that the electromagnetic valve 15 is in an abnormal state. A notification signal is output from the processing means included in the controller 2 in response to a determination of yes in step S4. For example, in response to this notification signal, the controller 2 stops outputting the control signal that operates the fuel supply control means 20. Thereby, the engine 1 stops.

  According to the present embodiment configured as described above, when the engine 1 is stopped during the operation, an abnormal one of the causes of the stop of the engine 1, that is, the electromagnetic valve 15 included in the lock lever device is abnormal. The operator can immediately know that it has occurred. Therefore, it is possible to shorten the time required for repairing the hydraulic circuit including the electromagnetic valve 15. Further, since the engine 1 is stopped when an abnormality occurs in the electromagnetic valve 15, the supply of pressure oil to the hydraulic actuator including the boom cylinder 34 is blocked, and the hydraulic pilot valve 11 and the like are set to the neutral position. Unintentional driving of the front work machine, the turning body, or the traveling body can be prevented, and further safety protection for the surroundings of the excavator can be realized.

  In the above-described embodiment, control for stopping the engine 1 is performed in accordance with a notification signal output from the processing means included in the controller 2, but the present invention is not limited to this. I can't.

  For example, a control that lowers the flow rate to a level at which the hydraulic power actuator can be supplied to the hydraulic actuator, or the main hydraulic pump, although the traveling body can be gently driven in response to the notification signal The discharge flow rate may be controlled to a predetermined low flow rate.

  Moreover, you may make it the structure provided with the alarm device which sounds the alarm which alerts the operator who sits in the driver's seat of a hydraulic excavator, and the circumference | surroundings of a hydraulic excavator according to a report signal.

  In addition, in the case where a display device is provided in the vicinity of the driver's seat, it may be configured to display that the electromagnetic valve 15 is abnormal on the display screen of the display device in response to the above notification signal.

It is a side view which shows the hydraulic excavator mentioned as an example of the construction machine with which one Embodiment of the operation function monitoring apparatus which concerns on this invention is provided. 1 is a hydraulic circuit diagram showing an embodiment of the present invention. It is a flowchart explaining the principal part operation | movement in one Embodiment of this invention.

Explanation of symbols

1 engine (motor)
2 Controller (Lock lever device)
3 Lock lever (lock lever device)
4 Detection switch (operation detection means) [Lock lever device]
5 Oil pressure detection sensor (permission detection means)
6 Main hydraulic pump 8 Directional control valve 8a Pilot chamber 8b Pilot chamber 9 Main line 10 Hydraulic pilot pump 11 Hydraulic pilot valve (operating device)
11a Pressure reducing valve 11b Pressure reducing valve 11c Operation lever 13 Pipe line 14a Pilot line 14b Pilot line 15 Solenoid valve [Lock lever device]
DESCRIPTION OF SYMBOLS 20 Fuel supply control means 31 Traveling body 32 Revolving body 33 Boom 34 Boom cylinder 35 Arm 36 Arm cylinder 37 Bucket 38 Bucket cylinder 39 Operation room

Claims (4)

A prime mover, a main hydraulic pump driven by the prime mover, a hydraulic actuator driven by pressure oil discharged from the main hydraulic pump, and a directional control valve for controlling inflow and outflow of the pressure oil to the hydraulic actuator And having
An electromagnetic valve for switching the output of an operation signal for switching the directional control valve, a lock lever for switching the solenoid valve, an operation detection means for detecting the operation of the lock lever, and the prime mover A drive control signal for driving, and a construction machine having a lock lever device including a controller for outputting a switching control signal for switching the electromagnetic valve in accordance with a signal output from the operation detection means;
Having permission detection means for detecting a permission signal that is output from the solenoid valve and permits the output of the operation signal;
The controller
It is determined whether or not the prime mover is being driven, it is determined whether or not the lock lever is held so that the solenoid valve is not permitted to output the operation signal, and the permission signal is detected by the permission detection means. Determining means for determining whether or not
The determination means determines that the prime mover is being driven, determines that the lock lever is held so that the solenoid valve is not permitted to output the operation signal, and the permission detection means further Processing means for performing a process of outputting a notification signal indicating that the solenoid valve is abnormal when it is determined that a permission signal is detected;
An operation function monitoring device for a construction machine, wherein the operation function of the electromagnetic valve of the lock lever device is monitored. In the invention of claim 1,
The operation function monitoring apparatus for a construction machine, wherein the controller performs a process of stopping the prime mover in response to the notification signal output from the processing means. In the invention of claim 1,
A hydraulic pilot pump driven by the prime mover and connected to the solenoid valve;
The operation device that outputs the operation signal is composed of a hydraulic pilot valve,
The permission signal output from the solenoid valve to the operating device when the solenoid valve is switched to the open position is a primary pressure discharged from the hydraulic pilot pump,
A construction machine operating function monitoring apparatus, wherein the permission detection means comprises a hydraulic pressure detection sensor for detecting the primary pressure output from the electromagnetic valve. In the invention of claim 1,
The construction machine is composed of a hydraulic excavator having a plurality of operation devices that output each of the operation signals, and one electromagnetic valve that switches between permitting and disabling the output of the operation signals from these operation devices. An operation function monitoring device for a construction machine.

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