JP3338653B2 - Work machine safety devices - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a safety device for a working machine such as a crawler crane, a hydraulic shovel, and a forklift.

[0002]

2. Description of the Related Art A working machine such as a crawler crane is provided with an operation lever which can be operated between an operation position and a neutral position, and by operating this operation lever, various actuators responding to operation of the operation lever are provided. (Eg, a hydraulic motor and a hydraulic cylinder) are driven to perform various operations. For example, the work machine travels by operating the operation lever of the traveling actuator, and the hoisting and lowering operation can be performed by operating the operation lever of the hoisting and lowering operation actuator.

When two actuators (for example, hoisting of a hanging hook and boom raising / lowering) are simultaneously driven like a crawler crane, one actuator (for example, a crawler crane) is used to improve operability and workability. A detent mechanism is provided for restraining the operation lever of the lifting of the suspension hook) to the operation position. And by this detent mechanism, 1
The operation lever of one actuator is fixed to the operation position, and the operation can be performed by operating the other operation lever (operation lever for raising and lowering the boom).

[0004] However, for example, when the crane is traveling, the operator concentrates on all the nerves while traveling, so even if the operation lever of the working actuator is moved to the operation position during traveling, the operator is not allowed to move. Often do not notice. Then, for example, if the operating lever for driving the hoist winch is erroneously hoisted during traveling and the state is left as it is, the hook is hoisted upward in accordance with the movement of the operating lever, and the hook Excessive winding may cause the boom to stand up and be pushed backward.

To prevent such a problem, for example, Japanese Patent Application Laid-Open No. 9-278362 discloses a safety device in which the driving of a working actuator such as a winch during traveling is prohibited. In this device, a switching valve is provided in the middle of a pipeline for supplying pilot pressure oil to a winch drive control valve. Then, the switching valve is switched according to the operation state of the pilot operation device for driving the traveling motor, and the supply of pilot pressure oil for winch driving is controlled. As a result, the winch is not driven even if the operating lever for driving the winch is accidentally operated during traveling.

[Problems to be solved by the invention]

However, in the device described in the above-mentioned publication, when one of the actuators is operated and the other actuator driving lever is operated, the driving of the actuator is suddenly stopped without the operator recognizing the operation. When the vehicle stops, an impact is generated, and the impact may shake the vehicle body and impair safety. Further, even when the two actuators are simultaneously driven by an intentional operation of the operator, the driving of the actuators is stopped, so that the workability deteriorates.

SUMMARY OF THE INVENTION It is an object of the present invention to make an operator recognize that another operation has been performed when an operation such as running of a working machine or a hoisting / unwinding operation is performed, and to prevent inconvenience such as boom tilt. An object of the present invention is to provide a safety device of a work machine for preventing the operation.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (1) Referring to FIGS. 1 and 7 showing an embodiment, the invention according to claim 1 is an operation position for driving a travel actuator 42 and the travel actuator. The operation device 32 for driving the vehicle to the neutral position for stopping the operation 42, and the operation actuator 4
The present invention is applied to a safety device for a work machine including at least work operation devices 35 and 36 that are operated at an operation position for driving the operation actuators 3 and 44 and a neutral position for stopping the operation actuators 43 and 44. Then, an alarm device 61 for issuing an alarm to the occupant, and an operation detector 5 for detecting the operation of the traveling operation device 32 and the work operation devices 35 and 36 to the operation positions.
7a, 60a, a boarding detector 71 for detecting the boarding posture of the occupant, the traveling operation device 32, and the work operation devices 35, 3
6 is in the operating position, and the control device 70 controls the operation of the alarm device 61 so as to issue an alarm when the boarding detector 71 does not detect the normal boarding posture of the occupant. Is achieved. (2) As shown in FIGS. 1 to 3, the invention according to claim 2 includes a traveling operation device 32 that is operated at an operation position for driving the traveling actuator 42 and a neutral position for stopping the traveling actuator 42. , Working actuators 43, 4
4 and the working actuator 43,
The present invention is applied to a safety device for a working machine having a boom 4 including at least a working operation device 35 and 36 which are operated to a neutral position for stopping the 44. Then, an alarm device 61 for issuing an alarm to the occupant, operation detectors 57a and 60a for detecting operation of the traveling operation device 32 and the operation operation devices 35 and 36 to the operation positions, and an angle α of the boom 4 are determined. The alarm device 61 is provided so as to issue an alarm when the angle detector 19 to be detected, the traveling operation device 32 and the operation operation devices 35 and 36 are both in the operation position, and the boom angle α becomes equal to or larger than the predetermined value θ1. The above-mentioned object is achieved by providing the control device 20 for controlling the operation of. (3) The invention according to claim 3 is the safety device for a work machine according to claim 2, further comprising a boarding detector 71 for detecting a boarding posture of the occupant, and the control device 70 comprising Alarm device 61 for issuing an alarm when both operating devices 35 and 36 are in the operating position, boom angle α is equal to or greater than predetermined value θ1, and boarding detector 71 does not detect a normal boarding posture of the occupant. This controls the operation of. (4) The safety device according to claim 2 or 3, further comprising the speed detecting means 17 for detecting a physical quantity according to the drive speed of the working actuators 43 and 44, wherein the safety device on the shore α is provided. , 44, the greater the driving speed, the smaller the predetermined value θ1 of the boom angle α at which an alarm is issued.

In the meantime, in the section of the means for solving the above-mentioned problem which explains the constitution of the present invention, the drawings of the embodiments of the present invention are used in order to make the present invention easy to understand. However, the present invention is not limited to this.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. First Embodiment FIG. 1 is a diagram showing a drive circuit of a hydraulic crawler crane to which the present invention is applied, FIG. 2 is a block diagram of a safety device according to the first embodiment, and FIG. FIG. 4 is a side view of a hydraulic crawler crane to which the present invention is applied, and FIG. 4 is a diagram showing an internal configuration of a cab. As shown in FIG. 3, the crawler crane includes a traveling body 1, a revolving body 3 rotatably mounted on the traveling body 1 via a revolving device 2, and a boom pivotally supported on the revolving body 3 so as to be able to undulate. And 4. The upper end of the boom 4 is supported by a hoisting rope 6 via a pendant rope 5, and the hoisting rope 6 is extended or wound by a hoisting drum 7 so that the boom 4 is raised and lowered. The main hook 8 is suspended from the tip of the boom 4 via the main winding rope 9, and the main hook 8 is raised and lowered by feeding or winding the main winding rope 9 by the main winding drum 10. An auxiliary hook 11 is suspended in front of the main hook 8, and the auxiliary hook 11 is raised and lowered by feeding or winding the auxiliary rope 13 by the auxiliary drum 12. The running, turning, hoisting, and undulating operations of the crane are executed by operations in the cab 14.

The boom foot section includes a pendulum type angle sensor 19 for detecting a boom ground angle α, a first boom overwind switch 15a whose operation can be released, and a second boom overwind switch whose operation cannot be released. A switch 15b is provided. First boom overwind switch 15 with boom angle of 80 °
a is the second boom overwind switch 1 with a boom angle of 82 °
5b is operated to stop driving the up-and-down drum 7, thereby stopping the boom 4 from standing up. When the second boom overwind switch 15b operates, the driving of the main winding drum 10 is also stopped. Above the main hook 8, a weight 16a for turning on / off a hook overwind switch is hung from the boom 4. When the weight 16a is lifted by raising the main hook 8, the hook overwind switch 16b is turned off, and the hook overwind is activated. Then, the driving of the main winding drum 10 is stopped, whereby the winding of the main hook 8 is stopped. Note that a rotation speed sensor 17 is provided on the prime mover 18 mounted on the upper rotating body 3, and detects the rotation speed of the prime mover 18. In addition, a control device 20 is mounted on the upper swing body 3,
The control device 20 performs the following processing.

As shown in FIG. 4, driving operation levers 32 and 33 for instructing driving of a driving actuator are provided on the right side of a driver's seat 31 provided at the center of the cab 14, and turning operation levers are provided on the left side. A turning operation lever 34 for instructing the drive of the actuator, a raising / lowering operating lever 35 for instructing the drive of a boom raising / lowering actuator in the front, a main winding operation lever 36 for instructing the driving of the main hook lifting actuator, An auxiliary winding operation lever 37 for instructing driving of an auxiliary hook winding actuator is provided. Among these, the main auxiliary winding operation levers 36 and 37 have a detent mechanism (not shown) so that the operation levers 36 and 37 are restricted to predetermined positions even when the operator stops the operation. Although not shown, the driver's cab 14 is provided with a display device for displaying various information relating to the work state and the like, and a speaker for issuing an alarm to alert the worker.

As shown in FIG. 1, in the present embodiment, a traveling hydraulic motor 42 corresponding to each of the operating levers 32, 35 and 36, and a hydraulic motor 43 for raising and lowering a hydraulic pump 41 driven by the prime mover 18. And hoisting hydraulic motor 4
4 are connected in series via control valves 45-47.
For simplicity of description, FIG.
Although only the hydraulic circuit diagram corresponding to 2, 35, 36 is shown, the configuration of the circuit corresponding to the other operation levers 33, 34, 37 is the same. Brake valves 42a to 44a are provided in front of the hydraulic motors 42 to 44.

The pilot chambers 45a of the control valves 45 to 47,
45b, 46a, 46b, 47a and 47b are pipes 51 to 5
6, pilot valves 32a, 32b, 35a, 35b, 36 driven by operation of operating levers 32, 35, 36
a, 36b, and each pilot valve 32a,
32b, 35a, 35b, 36a, 36b are connected to a pilot hydraulic pump 48. A shuttle valve 57 is provided between the pipeline 51 and the pipeline 52, and a pressure switch 57a that is turned on by supply of pressure oil is connected to the shuttle valve 57. Similarly, between line 53 and line 54, line 5
Shuttle valves 58 and 59 are also provided between the shuttle valve 5 and the pipe 56, and a shuttle valve 60 is provided in the middle of the pipe taken out from the shuttle valves 58 and 59.
Is provided with a pressure switch 60a that is turned on by the supply of pressure oil.

The pilot chambers 45a and 45b of the control valve 45
When the pilot pressure does not act on any of
5 is held at the illustrated neutral position by a spring 45c.
The same applies to the control valves 46 and 47. When the control valve 45 is in the neutral position, the hydraulic oil from the hydraulic pump 41 is guided to the control valve 46 without being supplied to the traveling hydraulic motor 42, and when the control valve 46 is in the neutral position, the pressure from the control valve 46 is The oil is guided to the control valve 47 without being supplied to the undulating hydraulic motor 43, and when the control valve 47 is in the neutral position, the control valve 4
The pressure oil from 7 is returned to the tank T without being supplied to the hoist hydraulic motor 44. Pilot chamber 4 of control valve 45
When the pilot pressure acts on 5a or 45b, the control valve 45 is switched to the A position or the B position, and the hydraulic motor 42 rotates by supplying the hydraulic oil to the hydraulic motor 42. The same applies to the control valves 46 and 47. The hydraulic circuit is provided with relief valves 49 and 50 for limiting the maximum pressure of the pressure oil supplied from the hydraulic pumps 41 and 48.

As shown in FIG. 2, a control device 20 according to the first embodiment includes a goniometer 19 for detecting the ground angle α of the boom 4 and a rotation speed sensor 17 for detecting the rotation speed of the prime mover 18. And pressure switches 57a and 60a for detecting the generation of pilot pressure in the pipelines 51 to 56 are connected. These detecting devices 17, 19 and pressure switch 5
When various input signals are input from 7a and 60a to the control device 20, the control device 20 executes predetermined processing and outputs output signals to a speaker 61 and a display device 62 provided in the cab 14.

Next, a process related to the generation of an alarm executed by the control device 20 will be described with reference to the flowchart of FIG. In this embodiment, the boom angle α becomes a predetermined angle θ1 (for example, 70 °) and the pressure switch 5
An alarm is issued when both 7a and 60a are turned on. Hereinafter, the details will be described.

The flowchart of FIG. 5 is started, for example, by turning on an engine key switch (not shown). First, in step S1, a boom angle at which an alarm is started based on a detection value from the rotation speed sensor 17 is set. The boom angle θ1 is calculated. The rotation speed of the hydraulic pump 41 depends on the rotation speed of the prime mover 18, and the driving speed of the hydraulic motors 42 to 44 increases as the rotation speed of the prime mover increases. When the driving speed of the hydraulic motors 42 to 44 is high, it is preferable to promptly alert the operator from the viewpoint of safety.
The calculation is performed so that the set boom angle θ1 becomes smaller as the prime mover rotation speed becomes higher. Next, in step S2, it is determined whether the pressure switch 57a is on. If step S2 is affirmed, the process proceeds to step S3, where it is determined whether or not the pressure switch 60a is on. If step S3 is affirmed, the process proceeds to step S4, where it is determined whether or not the boom angle α detected from the goniometer 19 is equal to or greater than the set boom angle θ1. If step S4 is affirmed, the speaker 61 is determined in step S5.
And outputs an ON signal for generating an alarm, and thereafter returns to the beginning to repeat the same processing. Step S2 to step S4
If any of the above is denied, the process proceeds to step S6, in which an off signal for generating an alarm is output to the speaker 61, and the process returns to the beginning.

Next, the operation of the first embodiment will be described. In the following description, the hook overwind switch 16
It is assumed that the hook overwinding device by b does not operate. When the traveling operation lever 32 is operated to start traveling of the crane, pressure oil corresponding to the operation amount is supplied to the pilot chamber 45a or 45b of the control valve 45,
The control valve 45 is switched to the A position or the B position, the traveling hydraulic motor 42 is driven, and the crane travels. At this time, the pressure switch 57a is turned on by the pilot pressure oil in the pipelines 51 and 52. If the main winding operation lever 36 is operated by mistake, pressure oil corresponding to the operation amount is supplied to the pilot chamber 47a or 47b of the control valve 47, and the control valve 47 is moved to the A position or the B position. The switch is switched to drive the hoisting hydraulic motor 44, and the hoisting operation of the main hook 8 is started during traveling. At this time, pipes 55 and 5
The pressure switch 60a is turned on by the pilot pressure oil in 6. Eventually, when the boom 4 is raised and lowered due to the excessive winding of the main hook 8 and the boom angle α becomes greater than or equal to the alarm boom angle θ1 (for example, 70 °) calculated based on the rotation speed of the prime mover,
For example, a voice message “Running. Return the hoisting operation lever to neutral.” Is issued from the speaker 61 to call attention to the operator. At the same time, an error message is displayed on the display device 62.

Incidentally, when the operating lever 35 for raising and lowering is operated during running, when the operating lever 32 for running is operated while the main hook 8 is being hoisted, or when the operating lever 36 for main winding is operated during turning. In such a case, a voice message is uttered from the speaker 61 in the same manner as described above, so that the operator recognizes that an erroneous operation has been performed.

As described above, according to the first embodiment, a warning is issued when, for example, the traveling operation and the hoisting operation are performed simultaneously and the boom angle α becomes equal to or greater than the set boom angle θ1. If the hoisting operation is performed by mistake and the boom angle α becomes greater than the set boom angle θ1, the operator can recognize the erroneous operation by an alarm and operate the operating lever with the boom angle α smaller than the set boom angle θ1. If the operator immediately recognizes the erroneous operation, no alarm is issued, and it is possible to prevent the operator's attention from becoming distracted by the occurrence of an unnecessary alarm. Further, since the set boom angle θ1 is set to a value (for example, 70 °) corresponding to the rotation speed of the prime mover 18, even if the winding speed of the main hook 8 increases due to the increase in the rotation speed of the prime mover, an alarm is generated. There is no delay.

Second Embodiment FIG. 6 is a block diagram of a safety device according to a second embodiment of the present invention. The hydraulic circuit diagram according to the second embodiment is the same as that in FIG. 1 and the description thereof is omitted. The same parts as those in FIG. 2 are denoted by the same reference numerals, and the differences are described below. I will mainly explain. As shown in FIG. 6, in the second embodiment, a seat sensor 71 is newly connected to the control device 70. The seating sensor 70 is a sensor provided in the driver's seat 31 for detecting the riding posture of the occupant in the driver's seat 31. The sensor is turned on when the driver is in the correct riding posture when looking straight ahead, leaves the driver's seat, or leans out of the driver's seat. Output an off signal when The controller 7 receives the input signal from the seating sensor 71 and
At 0, the following processing is executed.

FIG. 7 is a flowchart for explaining processing in the control device. The same portions as those in FIG. 5 are denoted by the same reference numerals, and the differences will be mainly described below. In FIG. 7, when it is determined in step S4 that the boom angle α is equal to or larger than the set boom angle θ1, the process proceeds to step S7,
It is determined whether the seating sensor 71 is on. Step S
If the result in step S7 is negative, the process proceeds to step S5 to output an ON signal for generating an alarm to the speaker 61, and if the result in step S7 is affirmative, the process proceeds to step S6 to output an OFF signal for generating an alarm to the speaker 61.

In actual work, running and hoisting operations may be performed simultaneously based on the recognition of the worker from the viewpoint of work efficiency. In such a case, it is not necessary to sound an alarm.
The determination as to whether the running and hoisting operations are being performed simultaneously based on the worker's consciousness is made based on whether or not the driver's seat 31 is properly seated. In other words, if the driver is seated correctly on the driver's seat 31, the driver looks straight ahead and is presumed to be working consciously. On the other hand, if the work is performed in a posture that looks away from the driver's seat 31 and looks down, it should be concentrated only on the work,
It is unlikely that different tasks will be performed simultaneously.

As described above, according to the second embodiment, the seating sensor 71 is provided in the driver's seat 31 to determine whether the simultaneous operation of running and winding is consciously performed, and consciously performing the operation. Since the warning is not issued when the warning is issued, it is possible to prevent the working environment from being deteriorated due to the unnecessary warning.

In the above embodiment, the set boom angle θ1 is set according to the rotation speed of the prime mover 18. However, the present invention is not limited to this. For example, the set boom angle θ1 is set according to the rope speed. You may. In this case, the rope speed can be calculated by detecting the rotation speed of the top sheave at the end of the boom and the winding layers of the drums 7, 10, and 12. Further, the set boom angle θ1 may be a fixed value irrespective of the rotation speed of the prime mover 18. Further, the condition that the boom angle α is equal to or larger than the set boom angle θ1 is omitted, and the pressure switch 5
The generation of an alarm may be controlled only by signals from the sensors 7a and 60a and the seating sensor 71.

In the above embodiment, the operation levers 32, 35, 36 are turned on by turning on the pressure switches 57a, 60a.
However, the present invention is not limited to this. For example, a microswitch is provided on the operation levers 32, 35, and 36,
The operation may be detected by turning on this switch. Furthermore, in the second embodiment, the seating sensor 71 recognizes whether the simultaneous operation of running and winding is consciously performed. However, the present invention is not limited to this. It may be configured to recognize whether the operation is a simple operation. As an example, a sensor that turns on when the grip of the operation lever is touched is installed, and when this sensor is on, it is recognized that it was consciously operated, and when it is off, it is recognized that it was mistakenly operated by detent. You may. Furthermore, the alarm is issued from the speaker 61, but the invention is not limited to this, and other sounds may be emitted from other than the speaker 61.

In the correspondence between the above embodiment and the claims, the traveling hydraulic motor 42 controls the traveling actuator,
The traveling operation lever 32 serves as a traveling operation device, the undulating hydraulic motor 43 and the hoisting hydraulic motor 44 serve as working actuators, and the undulating operating lever 35 and the main winding operation lever 36.
Is a work operation device, the speaker 61 is an alarm device, the pressure switches 57a and 60a are operation detectors, and the seating sensor 7
Reference numeral 1 denotes a boarding detector, the goniometer 19 forms an angle detector, and the rotation speed sensor 17 forms a speed detecting means.

[0029]

As described above, according to the present invention, the following effects can be obtained. (1) According to the first aspect of the present invention, an alarm is issued when the traveling operation device and the work operation device are both in the operation position and the boarding detector does not detect a normal riding posture of the occupant. Therefore, the operator can recognize an erroneous operation of the operation lever. In addition, when the traveling operation device and the work operation device are simultaneously operated based on the recognition of the operator, no alarm is transmitted to notify the operator of an erroneous operation of the operation lever. It does not get worse. (2) According to the second aspect of the present invention, an alarm is issued when both the traveling operation device and the work operation device are in the operation position and the boom angle is greater than or equal to a predetermined value. An erroneous operation of the operation lever can be recognized. Further, if the operator immediately recognizes an erroneous operation of the operation lever when the boom angle is less than the predetermined value, no alarm is issued and an unnecessary alarm can be prevented from being generated. (3) According to the fourth aspect of the invention, the boom angle at which a warning is issued becomes smaller as the driving speed of the working actuator is higher, so that the driving speed of the working actuator is increased due to an increase in the rotation speed of the prime mover. However, there is no delay in the generation of the alarm.

[Brief description of the drawings]

FIG. 1 is a diagram showing a driving circuit according to an embodiment of the present invention.

FIG. 2 is a block diagram of a safety device for a working machine according to the first embodiment.

FIG. 3 is a side view of the crane to which the embodiment is applied.

FIG. 4 is a diagram showing a configuration inside a cab of a crane to which the present embodiment is applied.

FIG. 5 is a flowchart for explaining processing executed by the control device according to the first embodiment;

FIG. 6 is a block diagram of a safety device for a working machine according to a second embodiment.

FIG. 7 is a flowchart illustrating a process executed by the control device according to the second embodiment;

[Explanation of symbols]

 4 Boom 17 Rotation speed sensor 19 Angle meter 20, 70 Controller 32 Operation lever for traveling 35 Operation lever for undulation 36 Operation lever for main winding 42 Hydraulic motor for traveling 43 Hydraulic motor for undulating 44 Hydraulic motor for hoisting 57a, 60a Pressure Switch 61 Speaker 71 Seating sensor

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B66C 15 / 00,23 / 90

Claims (4)

(57) [Claims] 1. A traveling operating device which is operated to an operating position for driving a traveling actuator and a neutral position for stopping the traveling actuator, an operating position for driving a working actuator, and stopping the working actuator. A safety device for a work machine including at least a work operation device that is operated in a neutral position, wherein an alarm device that issues an alarm to an occupant; and an operation position of the travel operation device and the work operation device. An operation detector for detecting an operation, a boarding detector for detecting an occupant's riding posture, and both the traveling operating device and the working operating device are operated
Position and the boarding detector is in a normal riding position for the occupant.
The alarm device so that an alarm is issued when no force is detected.
And a control device for controlling the operation of
Work machine safety equipment. 2. An operating position for driving a travel actuator.
Position and the neutral position to stop the travel actuator.
The operating device for traveling, the operating position for driving the working actuator and the operating device
For work operated to neutral position to stop the actuator
Work machine having a boom provided with at least an operating device
In the safety device, an alarm device for issuing an alarm to an occupant, and an operation position of the traveling operation device and the operation operation device.
An operation detector for detecting the operation of the vehicle, an angle detector for detecting the angle of the boom, and both the traveling operation device and the work operation device are operated.
Position, and the boom angle has exceeded a predetermined value.
Control the operation of the alarm device so as to generate an alarm
Work machine safety, comprising:
apparatus. 3. The safety device for a working machine according to claim 2,
Oite, further comprising a boarding detector for detecting the posture of the rider, the control device, operating the work and the travel operation device
Both devices are in the operating position and the boom angle is
Is greater than or equal to a fixed value and the boarding detector is
The alarm is issued so that an alarm is issued when the vehicle attitude is not detected.
Work machine safety characterized by controlling the operation of the device
apparatus. 4. The safety device for a work machine according to claim 2 , further comprising speed detection means for detecting a physical quantity according to a drive speed of the work actuator, wherein a higher drive speed of the work actuator is provided. A safety device for a work machine, wherein the predetermined value of the boom angle for issuing an alarm is reduced.