JPH07109745A - Operation room interference prevention device of working machine - Google Patents

Abstract

PURPOSE:To promote operation efficiency by making it possible to control boom rising and arm pulling in the case a buckets is out of a dangerous region in front of an operation room even if the bucket enters a dangerous region in the side of the operation room to stop an offset cylinder automatically. CONSTITUTION:Based on relative angle signals of a boom angle sensor 12, an offset angle sensor 13 and an arm angle sensor 14, a co-ordinate operating section 16 calculates a bucket front end co-ordinate. After that, in the case the front end of the bucket enters an interference dangerous region in the front of the operation room, a comparison operating section 19 inhibits first boom rising operation, arm pulling operation and second boom left offset operation. Then, the operating section 19 decides whether the front end of the bucket enters an interference dangerous region in the right side of the operation room, the left offset is inhibited in the case of entering. In addition, in the case of no entering, the first boom rising operation and arm pulling operation can be freely controlled in a deceleration state. According to the constitution, the front can be controlled at low speed in a small radius turning posture without uncertainty.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a driver's cab interference prevention device for a working machine, which stops the operation of each front member when the front approaches a driver's cab to avoid a collision between the two.
In particular, the present invention relates to a cab interference prevention device for a working machine suitable for use in a construction machine such as a small swing hydraulic excavator having an offset cylinder.

[0002]

2. Description of the Related Art FIG. 5 is a side view of a hydraulic excavator equipped with a conventional driver's cab interference prevention device, FIG. 6 is a plan view thereof, and FIG. 7 is an operation explanatory view of a front of the hydraulic excavator.

In these figures, 1 is a traveling body, 2 is a revolving structure having a driver's cab 2a and arranged above the traveling structure 1, and the traveling structure 1 and the revolving structure 2 constitute a working machine main body. is doing. Reference numeral 3 is a first boom rotatably connected to the revolving structure 2, 4 is a second boom rotatably connected to the tip of the first boom 3, and 5 is rotatably connected to the tip of the second boom. The arm 6 is a bucket rotatably connected to the tip of the arm 5, and the boom 7, 4 and the arm 5 and the bucket 6 form a front 7. 8 is a boom cylinder for driving the first boom 3, 9 is an offset cylinder for driving the second boom 4, 10 is an arm cylinder for driving the arm 5, 11 is a bucket cylinder for driving the bucket 6, and is shown in FIG. Thus, the second boom 4 moves the arm 5 and the bucket 6 in the lateral direction in parallel with the first boom 3 by the offset cylinder 9. Each of these cylinders 8, 9, 10, 11 is operated by an operation lever (not shown) arranged in the cab 2a, and when the operator appropriately operates the operation lever, based on an instruction signal according to the operation amount, The amount of pressure oil supplied to each cylinder 8, 9, 10, 11 is controlled.

Reference numeral 12 denotes a boom angle sensor provided in the vicinity of a connecting portion between the swing body 2 and the first boom 3, and detects a relative angle between the swing body 2 and the first boom 3. Also, 13 is the first
An offset angle sensor provided in the vicinity of a connecting portion between the boom 3 and the second boom 4, and the first boom 3 and the second boom 4 are provided.
The relative angle between them, that is, the offset angle is detected. Furthermore, 14 is an arm angle sensor provided in the vicinity of the connecting portion between the second boom 4 and the arm 5, and detects the relative angle between the second boom 4 and the arm 5. These sensors 12, 1
Each angle signal detected by 3, 14 is input to a controller (not shown), and the controller obtains the attitude of the front 7 from each angle signal and avoids the contact between the bucket 6 and the cab 2a. That is, as shown in FIGS. 5 and 6, a first interference danger area Z1 and a second interference danger area Z2 are set in front of and in the right side of the operator's cab 2a, respectively, and the controller uses the sensors 12, 13, When the coordinate position of the bucket 6 is calculated based on the angle signal from the bucket 14 and it is determined that the bucket 6 has entered the interference risk areas Z1 and Z2, the bucket 6 is irrespective of the instruction signal from the operation lever.
The operation of each part of the front 7 is stopped so that the vehicle does not approach the cab 2a any more.

Therefore, in the above-described conventional driver's cab interference prevention device, when the bucket 6 approaches the first interference risk region Z1 in front of the driver's cab 2a and the second interference risk region Z2 on the side of the driver's cab 2a, each part of the front 7 is affected. Since the operation is automatically stopped and the contact between the bucket 6 and the operator's cab 2a is avoided, it is possible to prevent damage to the machine and ensure the safety of the operator.

[0006]

By the way, in recent years, a lot of work is performed in a narrow place such as an urban area. When performing work in such a place, an operator operates an operating lever to operate each cylinder 8. , 9, 10, 11 must be driven to operate the attitude of the front 7 so that the turning radius becomes smaller. That is, the operator performs the raising operation of the first boom 3 and the pulling operation of the arm 5 to the maximum, and performs the left offset operation to bring the arm 5 and the bucket 6 as close as possible to the operator's cab 2a, and to make the turning radius of the front 7 as much as possible. Need to be small.

However, in the above-described conventional driver's cab interference prevention device, the bucket 6 is placed in the driver's cab 2a before the operation of raising the first boom 3 and the operation of pulling the arm 5 are maximized.
When entering the second interference danger area Z2 on the side of, the operation of each part of the front 7 is automatically stopped at that time, and the bucket 6 cannot be brought closer to the cab 2a any more. It does not take a small turning radius posture.
Therefore, in such a case, the operator performs the right offset operation to once move the bucket 6 to the outside of the second interference risk area Z2, and then performs the maximum raising operation of the first boom 3 and the maximum pulling operation of the arm 5. After that, however, it is necessary to perform the left offset operation again to bring the bucket 6 closer to the side of the driver's cab 2a, which causes a problem of poor operability.

The present invention has been made in view of the circumstances of the prior art as described above, and an object thereof is to perform an operation even when the bucket is stopped by an offset operation in a side interference risk area in the cab. An object of the present invention is to provide a driver's cab interference prevention device for a working machine, which can be safely placed in a small turning radius posture without interruption and has excellent operability.

[0009]

An object of the present invention described above is to provide a working machine main body having a cab, a first boom rotatably pin-connected to the working machine main body, and a first boom. Second boom movably connected in a lateral direction by an offset cylinder, an arm rotatably pinned to the second boom, and a bucket rotatably pinned to the arm. And operating means for instructing the operation of each front member composed of the first and second booms, the arm and the bucket, and a drive means for driving each front member based on an instruction signal from the operating means. A relative angle between the working machine main body and the front member, and an angle detecting means for detecting a relative angle between the front members, and a preliminary detection based on signals from these angle detecting means. Coordinate calculation means for calculating the coordinate values of the front in the set coordinate system, danger area setting means for setting an interference danger area in front of and in the side of the cab, and coordinates calculated by the coordinate calculation means From the value, it is determined whether or not the front has entered the interference danger area set in the danger area setting means, and when it is determined that the front has entered the interference danger area, the front direction toward the driver's cab In a driver's cab interference prevention device for a working machine, which is provided with a comparison calculation unit that outputs a stop signal that prohibits movement, a stop signal is input from the comparison calculation unit, and the front side may interfere with the side of the cab. A control signal that enables the raising operation of the first boom and the pulling operation of the arm is output to the drive means while the operation of the offset cylinder is stopped by entering the area. It is achieved by providing a driving control means for.

Further, the above-mentioned object of the present invention is that the control signal output from the drive control means to the drive means when the operation of the offset cylinder in the interference danger area is stopped is used as an instruction signal of the operation means. Based on a signal that is decelerated with respect to the raising speed of the first boom and the pulling speed of the arm based on the above.

[0011]

When the operator operates the operating lever, the drive control means inputs a stop signal from the comparison calculation means, and in accordance with these signals, the drive means for supplying hydraulic oil to each front member, for example, a predetermined hydraulic drive circuit. The signal of is output. For example, when operating the operation lever so that the front is in a small turning radius posture, if the bucket is moved into the interference danger area on the side of the cab by performing an offset operation, the drive control means causes the hydraulic drive circuit of the offset cylinder to A signal for stopping the supply of hydraulic oil to the offset cylinder is output, and the offset cylinder automatically stops in spite of the offset operation, thereby avoiding a collision between the bucket and the side of the cab.
In this state, when the bucket does not enter the interference danger area in front of the operator's cab, the drive control means causes the boom directional switching valve for driving the boom cylinder and the arm directional switching valve for driving the arm cylinder to: A control signal for reducing the pilot pressure below the pilot pressure based on an instruction signal from the operating means is output, and the raising operation of the first boom and the pulling operation of the arm are decelerated. Therefore, the bucket can be slowly operated without interrupting the work until it enters the interference danger area in front of the operator's cab, and the front has a small turning radius posture.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 3 illustrate a first embodiment of a cab interference prevention device for a working machine according to the present invention. FIG. 1 is a block diagram showing the overall configuration of the cab interference prevention device, and FIG. 2 is a hydraulic drive circuit. FIG. 3 is a flowchart showing the processing contents of the arithmetic unit, and parts corresponding to those in FIGS.

In FIG. 1, reference numerals 12, 13, and 14 denote the boom angle sensor, the offset angle sensor, and the arm angle sensor described above. The relative angle signal θ1 between the front members detected by these sensors 12, 13, 14 is shown. , Θ2
θ3 is input to the arithmetic unit 15 incorporated in the controller. The arithmetic unit 15 is configured to detect the angle signals θ1, θ2, θ3.
A coordinate calculation unit 1 that calculates the bucket tip coordinates from the coordinates of a predetermined point on the front 7, for example, the tip of the arm 5 based on
6, a first interference danger area storage unit 17 and a second interference danger area storage unit 18 that set a first interference danger area Z1 and a second interference danger area Z2 in the front and right sides of the cab 2a, respectively.
And a comparison calculation unit that determines whether or not the bucket tip coordinates calculated by the coordinate calculation unit 16 are in the first or second interference danger area storage units 17 and 18, and outputs a stop signal according to the result. 19, and a drive means for supplying hydraulic oil to each front member based on a stop signal from the comparison calculation part 19, for example, a drive control part 20 for outputting a predetermined control signal to a hydraulic drive circuit 21. This hydraulic drive circuit 21
In addition to the control signal from the drive controller 20, the driver's cab 2a
An operation signal for operating each front member arranged inside, for example, an instruction signal from an operation lever 22 is input, and the amount of hydraulic oil supplied to each front member is controlled based on these signals. When calculating the bucket tip coordinates, for example, a coordinate system whose origin is the connection center between the revolving unit 2 and the first boom 3 is set in advance, and each angle signal θ1,
The coordinate value of the tip of the arm 5 in this coordinate system is calculated from θ2 and θ3, and the bucket 6 is calculated from the coordinate value of the arm tip.
It suffices to calculate the coordinate value of the tip of the.

As shown in FIG. 2, the hydraulic drive circuit 21.
Are a hydraulic pump 23 driven by a prime mover, a pilot pump 24, a boom direction switching valve 25 for controlling the flow of hydraulic oil supplied from the hydraulic pump 23 to each of the cylinders 8, 9 and 10, and an offset direction switching valve. 26, an arm direction switching valve 27, a boom pilot valve 28 for operating the cylinders 8, 9 and 10, an offset pilot valve 29, an arm pilot valve 30 and the like, and a bucket cylinder 11 and a traveling motor. Other actuators are omitted from the drawing. Each pilot valve 28, 29, 30 has a left chamber and a right chamber communicating with the pilot pump 24, and the pressure oil discharged from the pilot pump 24 corresponds to an instruction signal from the operation lever 22. Depending on these, these are supplied to the left or right chamber.

The boom directional control valve 25 has pilot chambers on both left and right sides.
5 left pilot chamber and the boom pilot valve 2
The chamber on the left side of 8 is connected by a boom raising pilot line 31, and the pilot chamber on the right side of the boom direction switching valve 25 and the chamber on the right side of the boom pilot valve 28 are connected by a boom lowering pilot line 32. There is. The offset directional control valve 26 also has pilot chambers on both left and right sides.
The pilot chamber on the left side of 6 and the chamber on the left side of the offset pilot valve 29 are arranged in the right offset pilot line 33.
The pilot chamber on the right side of the offset directional control valve 26 and the chamber on the right side of the offset pilot valve 29 are connected by a left offset pilot conduit 34. Further, the arm directional control valve 27 also has pilot chambers on both left and right sides. The pilot chamber on the left side of the arm directional control valve 27 and the chamber on the left side of the arm pilot valve 30 are arm pull pilot pipes. Road 35
And the right pilot chamber of the arm directional control valve 27 and the right chamber of the arm pilot valve 30 are connected by an arm pushing pilot conduit 36.

An electromagnetic proportional pressure reducing valve 37 for a boom is provided in the boom raising pilot line 31, and an electromagnetic proportional pressure reducing valve 38 for an arm is provided in the arm pulling pilot line 35. These electromagnetic proportional pressure reducing valves are provided. 37 and 38 have ports connected to the tank. These electromagnetic proportional pressure reducing valves 37 and 38 are used as the drive control unit 20 of the arithmetic unit 15.
Is operated in proportion to the current value of the control signal output from
Normally, the maximum level control signal is input to fully open the boom raising pilot line 31 and the arm pulling pilot line 35, and the switching signal IA having the minimum current value is used as a control signal.
Is input, the pressure oil in the boom raising pilot line 31 and the arm pulling pilot line 35 is shut off and returned to the tank, and when the switching signal IB whose current value is larger than IA is input as the control signal, the boom raising pilot The pilot pressure is reduced by squeezing the pressure oil in the conduit 31 and the arm-pulling pilot conduit 35. On the other hand, a boom electromagnetic switching valve 39 is provided in the boom lowering pilot conduit 32, and an offset electromagnetic switching valve 40 is interposed in the left offset pilot conduit 34. These electromagnetic switching valves 39, 40 are provided.
Has a port connected to the tank. These electromagnetic switching valves 39 and 40 are also drive control units 20 of the arithmetic unit 15.
The switching operation is performed by the control signal output from the control device, and only when the control signal is input, the pressure oil in the boom lowering pilot conduit 32 and the left offset pilot conduit 34 is shut off and returned to the tank.

The operation of this embodiment will be described below with reference to the flow charts shown in FIGS. 1, 2 and 3.

In the case of a normal front operation in which there is no risk of contact between the tip of the bucket 6 and the operator's cab 2a, that is, the first and second interference risks in which the bucket 6 is set in front of and in the side of the operator's cab 2a, respectively. When located outside the zones Z1 and Z2, the boom and arm electromagnetic proportional pressure reducing valves 3
7, 38 and electromagnetic switching valve for boom and offset 3
9, 40 are all in the positions shown in FIG. In this state, for example, when the boom operation lever 22 is tilted to the left side in FIG. 2, the pressure oil discharged from the pilot pump 24 is supplied from the chamber on the left side of the boom pilot valve 28 to the boom raising pilot conduit 31 and the boom. Is supplied to the pilot chamber on the left side of the boom direction switching valve 25 via the electromagnetic proportional pressure reducing valve 37,
The boom direction switching valve 25 starts to operate. Then, when the boom direction switching valve 25 is switched from the neutral position to the left position, the pressure oil of the hydraulic pump 23 is supplied to the bottom side of the boom cylinder 8 via the boom direction switching valve 25, and the boom cylinder 8 extends. Then, the first boom 3 rises. On the contrary, the operating lever 22 for the boom is shown in FIG.
When it is tilted to the right side, the pressure oil discharged from the pilot pump 24 flows from the chamber on the right side of the boom pilot valve 28 to the boom lowering pilot conduit 32 and the boom electromagnetic switching valve 39.
Is supplied to the pilot chamber on the right side of the boom direction switching valve 25, and the boom direction switching valve 25 starts to operate.
Then, when the boom direction switching valve 25 is switched from the neutral position to the right position, the pressure oil of the hydraulic pump 23 is supplied to the rod side of the boom cylinder 8 via the boom direction switching valve 25, and the boom cylinder 8 expands and contracts. The first boom 3 descends. Similarly, the offset cylinder 9 expands and contracts according to the operation amount of the offset operation lever 22, and the arm 5 and the bucket 6 are laterally right or left offset with respect to the first boom 3, and the operation lever 2
The arm cylinder 10 expands and contracts according to the operation amount of 2, and the arm 5 is pulled or pushed.

At this time, the arithmetic unit 15 first outputs the relative angle signals θ1, θ2, θ3 from the boom angle sensor 12, the offset angle sensor 13 and the arm angle sensor 14, as shown in step S-1 of FIG. Input to the coordinate calculation unit 16,
Next, in step S-2, the relative angle signals θ1, θ2, θ
After the coordinates of the tip of the arm 5 are calculated from 3, the bucket tip coordinates are calculated from the arm tip coordinates in step S-3. Next, the process proceeds to step S-4, and the comparison calculation unit 19 determines, based on the bucket tip coordinates calculated by the coordinate calculation unit 16 and the first interference risk area Z1 stored in the first interference risk area storage unit 17. It is determined whether or not the tip of the bucket 6 has entered the first interference risk area Z1 set in front of the cab 2a.

When the result of the determination in step S-4 is YES, the process proceeds to step S-5, and the raising operation of the first boom 3, the pulling operation of the arm 5 and the left offset operation are all prohibited. That is, the comparison calculation unit 19 outputs a stop signal for stopping the drive of the boom cylinder 8, the offset cylinder 9, and the arm cylinder 10 to the drive control unit 20, and the drive control unit 20 causes the hydraulic drive circuit 21 to perform the electromagnetic proportional movement for the boom. The switching signal IA is output to the pressure reducing valve 37 and the arm electromagnetic proportional pressure reducing valve 38, respectively, and the switching signals are output to the boom electromagnetic switching valve 39 and the offset electromagnetic switching valve 40, respectively. Then, the electromagnetic proportional pressure reducing valves 37 and 38 for the boom and the arm are switched to the right position in FIG. 2, and the pressure oil in the boom raising pilot line 31 and the arm pulling pilot line 35 is shut off and returned to the tank. The boom and offset electromagnetic switching valves 39, 40 are switched to the left position in FIG. 2 to shut off the pressure oil in the boom lowering pilot conduit 32 and the left offset pilot conduit 34 and return it to the tank.
Therefore, even if the operating levers 22 are operated to supply pressure oil from the pilot pump 24 to the boom raising pilot conduit 31, the arm pulling pilot conduit 35, and the left offset pilot conduit 34, these conduits 31,
Pilot pressure does not build up at 34 and 35, and the raising operation of the first boom 3, the pulling operation of the arm 5, and the left offset operation are prohibited.

On the other hand, when the determination result in step S-4 is NO, the process proceeds to step S-6, and in step S-6, the comparison calculation section 19 compares the bucket tip coordinates calculated by the coordinate calculation section 16 with the first point. Based on the second interference danger area Z2 stored in the second interference danger area storage unit 18, it is determined whether or not the tip of the bucket 6 has entered the second interference danger area Z2 set on the right side of the cab 2a. to decide.

When the result of the determination in step S-6 is YES,
That is, when the bucket 5 is outside the first interference danger area Z1 in front of the operator's cab 2a and enters the second interference danger area Z2 on the right of the operator's cab 2a, the procedure proceeds to step S-7 and the left offset is performed. Prohibit operation. In this case, the comparison calculation unit 19 instructs the drive control unit 20 to perform the offset cylinder 9
The drive control unit 20 outputs a switching signal to the offset electromagnetic switching valve 40 of the hydraulic drive circuit 21. Then, as described above, the electromagnetic switching valve for offset 40 is switched to the left position in FIG. 2, and the pressure oil in the left offset pilot conduit 34 is shut off and returned to the tank. Therefore, the offset operation lever 22 operates the left offset operation. Even if it is performed, the offset cylinder 9 does not operate, and the left offset operation is prohibited.

In the next step S-8, when there is no input for raising the first boom 3 and pulling input for the arm 5, the procedure returns to step S-1, and when there is input for raising the first boom 3 and pulling input for the arm 5. In step S-9, the raising operation of the first boom 3 and the pulling operation of the arm 5 are enabled. In this case, the drive control unit 20 outputs the switching signal IB to the boom electromagnetic proportional pressure reducing valve 37 and the arm electromagnetic proportional pressure reducing valve 38 of the hydraulic drive circuit 21, and the offset electromagnetic switching valve 4 is provided.
The switching signal is output to 0. Then, the electromagnetic proportional pressure reducing valves 37 and 38 for the boom and the arm are switched to the rightward direction in FIG. 2, and the pressure oil in the boom raising pilot line 31 and the arm pulling pilot line 35 is reduced to reduce the pilot pressure, Further, the electromagnetic switching valve for offset 40 is switched to the left position in FIG. 2, shuts off the pressure oil in the left offset pilot pipe line 34, and returns it to the tank. Accordingly, when the first boom raising operation and the arm 5 pulling operation are performed in a state where the offset cylinder 9 is automatically stopped by performing the left offset operation, the left side of the boom direction switching valve 25 and the arm direction switching valve 27 are changed. The pressure oil supplied to the pilot chamber becomes lower than the pilot pressure corresponding to the operation amount of the operation lever 22, and the boom cylinder 8 and the offset cylinder 9 are operated at a speed slower than the normal operation speed.

When the result of the determination in step S-6 is NO, the process proceeds to step S-10 to enable normal front operation. That is, in this case, the boom and arm electromagnetic proportional pressure reducing valves 37, 38 and the boom and offset electromagnetic switching valves 39, 40 are all in the positions shown in FIG. 2, and the cylinders 8, 9, 10, 11 correspond to each other. It is driven according to the operation amount of the operating lever 22 to be operated.

As described above, in the first embodiment,
Even when the bucket 6 enters the interference danger zone Z2 on the side of the cab 2a and the offset cylinder 9 is automatically stopped,
When the bucket 6 is located outside the interference danger area Z1 in front of the operator's cab 2a, the raising operation of the first boom 3 and the pulling operation of the arm 5 can be continuously performed without interrupting the work. A small turning radius posture can be achieved with a simple operation. Moreover, in this case, since the raising operation of the first boom 3 and the pulling operation of the arm 5 can be performed more slowly than the normal operation speed, the operator can place the front 7 in the small turning radius posture without feeling uneasy. it can.

FIG. 4 illustrates a second embodiment of the present invention, and is a block diagram showing an overall configuration of a driver's cab interference prevention device. As shown in the figure, in the second embodiment, the drive control unit 20 of the arithmetic unit 15 inputs the instruction signal from each operation lever 22 in addition to the stop signal from the comparison arithmetic unit 19, and outputs these signals. Based on this, a predetermined control signal is output to the hydraulic drive circuit 21. For example, the tip of the bucket 6 and the cab 2a
In the case of a normal front operation in which there is no risk of contact with the drive control section 20, the drive control section 20 outputs a control signal corresponding to the operation amount of each operation lever 22 to the hydraulic drive circuit 21, and each front section is driven at a normal operation speed. It When the tip of the bucket 6 enters the interference danger zone Z1 in front of the operator's cab 2a, the drive control unit 20 causes the hydraulic drive circuit 21 to operate the cylinders 8, 9 ,.
A control signal for stopping 10 is output to prohibit all of the raising operation of the first boom 3, the pulling operation of the arm 5 and the left offset operation. Further, the tip of the bucket 6 is located in the cab 2a.
When it enters the interference danger zone Z2 on the side of, the drive control unit 20 outputs a control signal for stopping the offset cylinder 9 to the hydraulic drive circuit 21 and a control signal for decelerating the boom cylinder 8 and the arm cylinder 10. It outputs and enables the raising operation of the first boom 3 and the pulling operation of the arm 5. The rest of the configuration is similar to that of the first embodiment,
The description is omitted.

Also in the second embodiment, when the offset cylinder 9 is automatically stopped by the left offset operation,
Since the raising operation of the first boom 3 and the pulling operation of the arm 5 can be continuously performed without interrupting the work, the front 7 can be brought into a small turning radius posture by a simple operation, and the operation in this case is usually performed. Since the operation can be performed at a speed slower than the operating speed, the operator can put the front 7 in the small turning radius posture without feeling uneasy.

[0028]

As described above, according to the present invention,
Even if the bucket enters the interference risk area on the side of the operator's cab and the offset cylinder is automatically stopped, if the bucket is located outside the interference danger area in front of the operator's cab, the work will continue without interruption. Since the first boom raising operation and the arm pulling operation can be continuously performed, the front can be made into a small turning radius posture by a simple operation. Moreover, in this case, the first boom raising operation and the arm pulling operation are normally performed. Since the operation can be performed at a speed slower than the operating speed of, the operator can set the front to a small turning radius posture without feeling uneasy.

[Brief description of drawings]

FIG. 1 is a block diagram showing an overall configuration of a driver's cab interference prevention device for a working machine according to a first embodiment of the present invention.

FIG. 2 is a circuit diagram showing a hydraulic drive circuit of FIG.

FIG. 3 is a flowchart showing the processing contents of the arithmetic unit of FIG.

FIG. 4 is a block diagram showing an overall configuration of a driver's cab interference prevention device for a working machine according to a second embodiment of the present invention.

FIG. 5 is a side view of a hydraulic excavator provided with a cab interference prevention device.

FIG. 6 is a plan view of the hydraulic excavator.

7 is an operation explanatory view of the front of the hydraulic excavator of FIG.

[Explanation of symbols]

 2 Revolving structure 2a Operator's cab 3 1st boom 4 2nd boom 5 Arm 6 Bucket 7 Front 8 Boom cylinder 9 Offset cylinder 10 Arm cylinder 12 Boom angle sensor (angle detection means) 13 Offset angle sensor (angle detection means) 14 Arm angle Sensor (angle detecting means) 15 Computing device 16 Coordinate computing section (coordinate computing means) 17 First interference danger area storage section (danger area setting means) 18 Second interference danger area storage section (danger area setting means) 19 Comparison computing section (Comparison calculation means) 20 Drive control section (drive control means) 21 Hydraulic drive circuit (drive means) 22 Operating lever (operating means) 25 Boom directional control valve 26 Offset directional control valve 27 Arm directional control valve 28 Boom Pilot valve 29 Offset pilot valve 30 Arm pilot valve 31 Raise pilot line 32 Boom down pilot line 34 Left offset pilot line 35 Arm pull pilot line 37 Boom electromagnetic proportional pressure reducing valve 38 Arm electromagnetic proportional pressure reducing valve 39 Boom electromagnetic switching valve 40 Offset electromagnetic switching valve

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Shudo Yamada 20 Ishigane Co., Ltd., Toyama City, Toyama Prefecture (72) Inventor Akinori Shimamae 20 Ishigane Co., Ltd., Toyama City, Toyama Prefecture (72) Invention Takashi Matsuda 20 Ishigane, Toyama City, Toyama Prefecture Fujikoshi Co., Ltd.

Claims (2)

[Claims] 1. A working machine main body having a driver's cab, a first boom pivotally connected to the working machine main body, and a laterally movably connected to the first boom by an offset cylinder. A second boom, an arm rotatably pin-connected to the second boom, a bucket rotatably pin-connected to the arm, and the first and second booms and the arm. An operating means for instructing the operation of each front member composed of a bucket, a driving means for driving each front member based on an instruction signal from the operating means, and a relative position between the working machine body and the front member. Angle detection means for detecting the angle and the relative angle between the front members, and the front of the front in a coordinate system preset based on signals from these angle detection means. Coordinate calculation means for calculating coordinate values,
Danger area setting means for setting an interference danger area in the front and side of the cab, and the front enters the interference danger area set in the danger area setting means from the coordinate values calculated by the coordinate calculation means. Of the working machine that outputs a stop signal for prohibiting movement of the front toward the cab when it is determined that the front has entered the interference risk area. In the driver's cab interference prevention device, when the stop signal is input from the comparison calculation means, the front enters the interference risk region on the side of the driver's cab, and the operation of the offset cylinder is stopped, the first A driver's cab interference prevention device for a working machine, comprising drive control means for outputting to the drive means a control signal enabling a raising operation of a boom and a pulling operation of the arm. 2. The control signal output from the drive control means to the drive means when the operation of the offset cylinder in the interference risk area is stopped according to claim 1, based on an instruction signal of the operation means. A driver's cab interference prevention device for a working machine, which is a signal for decelerating the raising speed of the first boom and the pulling speed of the arm.