WO2024042875A1

WO2024042875A1 - Control device, control method, and working machine

Info

Publication number: WO2024042875A1
Application number: PCT/JP2023/024786
Authority: WO
Inventors: 利江川又; 良太榎本; 雄二福田; 勝西藤; 雄一寺西; 大輔高木
Original assignee: 株式会社小松製作所
Priority date: 2022-08-25
Filing date: 2023-07-04
Publication date: 2024-02-29
Also published as: JP2024030958A

Abstract

This control device comprises: an acquisition unit which repetitively acquires a first detection signal output in response to a tilt amount of an operation lever of a working machine that is tilted, from a neutral position, in a first direction or a second direction that is an opposite direction to the first direction, by a first tilt amount sensor which detects the tilt amount, and a second detection signal output by a second tilt amount sensor in response to the tilt amount; and a control unit which repetitively determines, during a prescribed time, whether the first and second detection signals are at values corresponding to the neural position at the start of the working machine when both the first and second detection signals are not at the values corresponding to the neural position, outputs an alarm for indicating such a case from a prescribed output unit and stops outputting the alarm and generates and outputs a prescribed control signal for controlling the working machine on the basis of the first detection signal when both the first and second detection signals become the values corresponding to the neural position before the prescribed time elapses.

Description

Control device, control method and working machine

The present disclosure relates to a control device, a control method, and a work machine.
This application claims priority to Japanese Patent Application No. 2022-134218 filed in Japan on August 25, 2022, the contents of which are incorporated herein.

Patent Document 1 discloses that the tilting angle of the operating lever of a working machine (movable body) is detected and compared using two detection units, the presence or absence of an abnormality is determined based on the comparison result, and if it is abnormal, the angle is small. A control device is described that controls a work machine based on the detection result of one of the two. The two detection units described in Patent Document 1 have a characteristic that one of them decreases the voltage of the detection signal as the angle increases, and the other increases the voltage of the detection signal as the angle increases. Then, the control device determines whether there is an abnormality by comparing the total value of the two detection signals with a normal value.

Japanese Patent Application Publication No. 2006-328759

The control device described in Patent Document 1 operates the work machine at a faster speed as the tilt angle of the operating lever from the neutral position is larger. For this reason, for example, if an abnormality occurs in the two detection units in that they are only able to output a signal indicating that the tilting angle from the neutral position is large, the control of the work equipment may become inappropriate. There is a problem.

The present disclosure has been made in view of the above circumstances, and provides a control device, a control method, and a work machine that can appropriately deal with the occurrence of an abnormality in the detection of the tilt amount of the operating lever of the work machine. The purpose is to

One aspect of the present disclosure is a control device for a work machine including a work machine, wherein an operating lever of the work machine is tilted from a neutral position in a first direction or in a second direction opposite to the first direction. a first detection signal outputted by a first tilting amount sensor that detects the tilting amount according to the tilting amount; and a second detection signal outputted by a second tilting amount sensor that detects the tilting amount according to the tilting amount. an acquisition unit that repeatedly acquires the information; and an acquisition unit that repeatedly determines for a predetermined period whether or not the first detection signal and the second detection signal are values corresponding to the neutral position when starting the work machine, and determines whether the first detection signal and the second detection signal are values corresponding to the neutral position; If both of the second detection signals do not have values corresponding to the neutral position, a predetermined output section outputs a warning to that effect, and the first detection signal and the second detection signal are outputted before the predetermined time elapses. and a control unit that stops outputting the alarm when both of the values correspond to the neutral position, and generates and outputs a predetermined control signal for controlling the work equipment based on the first detection signal. A control device comprising:

One aspect of the present disclosure is a method for controlling a working machine including a working machine, in which a control lever of the working machine is tilted from a neutral position in a first direction or in a second direction opposite to the first direction. a first detection signal outputted by a first tilting amount sensor that detects the tilting amount according to the tilting amount; and a second detection signal outputted by a second tilting amount sensor that detects the tilting amount according to the tilting amount. a step of repeatedly acquiring the information; and repeatedly determining for a predetermined time whether or not the first detection signal and the second detection signal have values corresponding to the neutral position when starting the working machine; If both of the second detection signals do not have values corresponding to the neutral position, a warning to that effect is output from a predetermined output section, and before the predetermined time elapses, the first detection signal and the second detection signal are when both have values corresponding to the neutral position, stopping the output of the alarm, and generating and outputting a predetermined control signal for controlling the working machine based on the first detection signal. This is a control method that includes

One aspect of the present disclosure provides a work machine and a first tilt amount sensor that detects a tilt amount of an operating lever of the work machine that is tilted from a neutral position in a first direction or a second direction opposite to the first direction. an acquisition unit that repeatedly acquires a first detection signal outputted by the sensor according to the tilting amount and a second detection signal outputted by a second tilting amount sensor that detects the tilting amount according to the tilting amount; When the machine is started, it is repeatedly determined for a predetermined period whether or not the first detection signal and the second detection signal have values corresponding to the neutral position; If the value does not correspond to the neutral position, a warning to that effect is output from a predetermined output section, and both the first detection signal and the second detection signal correspond to the neutral position before the predetermined time elapses. The working machine further includes a control unit that stops outputting the alarm when the first detection signal reaches the specified value, and generates and outputs a predetermined control signal for controlling the working machine based on the first detection signal.

According to the control device, control method, and working machine of the present disclosure, it is possible to appropriately deal with an abnormality in the detection of the tilt amount of the operating lever of the working machine.

FIG. 1 is a side view showing a working machine according to an embodiment of the present disclosure. FIG. 1 is a block diagram illustrating a configuration example of a control system for a work machine according to an embodiment of the present disclosure. FIG. 2 is a cross-sectional view showing an operating lever according to an embodiment of the present disclosure. FIG. 2 is a cross-sectional view showing an operating lever according to an embodiment of the present disclosure. FIG. 3 is an output characteristic diagram of an angle sensor according to an embodiment of the present disclosure. FIG. 3 is a state transition diagram illustrating an example of the operation of the controller according to the embodiment of the present disclosure. FIG. 3 is a schematic diagram for explaining an example of the operation of the controller according to the embodiment of the present disclosure. FIG. 3 is a schematic diagram for explaining an example of the operation of the controller according to the embodiment of the present disclosure. FIG. 3 is a schematic diagram for explaining an example of the operation of the controller according to the embodiment of the present disclosure. FIG. 3 is a schematic diagram for explaining an example of the operation of the controller according to the embodiment of the present disclosure.

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In addition, in each figure, the same reference numerals are used for the same or corresponding components, and the description thereof will be omitted as appropriate.

In this embodiment, a local coordinate system is set in the work machine 1, and the positional relationship of each part will be explained with reference to the local coordinate system. In the local coordinate system, the first axis extending in the left-right direction (vehicle width direction) of the work machine 1 is the X-axis, the second axis extending in the front-rear direction of the work machine 1 is the Y-axis, and the vertical direction of the work machine 1 is the Y-axis. Let the third axis extending to the Z axis be the Z axis. The X-axis and Y-axis are orthogonal. The Y axis and the Z axis are orthogonal. The Z axis and the X axis are orthogonal. The +X direction is the right direction, and the -X direction is the left direction. The +Y direction is the front direction, and the -Y direction is the rear direction. The +Z direction is the upward direction, and the -Z direction is the downward direction.

[Overview of working machine]
FIG. 1 is a side view showing a working machine 1 according to the present embodiment. The working machine 1 according to this embodiment is, for example, a wheel loader. In the following description, the work machine 1 will be appropriately referred to as a wheel loader 1.

As shown in FIG. 1, the wheel loader 1 includes a vehicle body 2, a cab 3, a traveling device 4, and a working machine 10. The wheel loader 1 travels around the work site using a traveling device 4. The wheel loader 1 performs work using a work machine 10 at a work site. The wheel loader 1 can use the working machine 10 to perform tasks such as excavation work, loading work, transportation work, and snow removal work.

The cab 3 is supported by the vehicle body 2. Inside the cab 3, a driver's seat 31 in which an operator sits, an operating device 32 to be described later, a display input section 35, and an output section 36 are arranged.

The traveling device 4 has rotatable wheels 5. The wheels 5 support the vehicle body 2. The wheel loader 1 can travel on a road surface (or ground) RS using a traveling device 4. In addition, in FIG. 1, only the left front wheel 5F and rear wheel 5R are illustrated.

The work machine 10 is supported by the vehicle body 2. The work machine 10 includes a bucket 12 as an example of a work tool, and a movable support part 17 that changes the position and attitude of the bucket 12. In the example shown in FIG. 1 , the movable support section 17 includes a boom 11 , a boom cylinder 13 , a bucket cylinder 14 , a bell crank 15 , and a link 16 .

The boom 11 is rotatably supported with respect to the vehicle body 2 and moves in the vertical direction according to the expansion and contraction of the boom cylinder 13. The boom cylinder 13 is an actuator that generates power for moving the boom 11, and one end is connected to the vehicle body 2 and the other end is connected to the boom 11. When the operator operates a boom operating lever 33 (FIG. 2) included in the operating device 32, the boom cylinder 13 expands and contracts. This causes the boom 11 to move in the vertical direction. The boom cylinder 13 is, for example, a hydraulic cylinder.

The bucket 12 has a cutting edge 12T and is a working tool for digging and loading objects to be excavated such as earth and sand. The bucket 12 is rotatably connected to the boom 11 and rotatably connected to one end of the link 16 . The other end of the link 16 is rotatably connected to one end of the bell crank 15. The bell crank 15 has a center portion rotatably connected to the boom 11, and the other end portion rotatably connected to one end portion of the bucket cylinder 14. The other end of the bucket cylinder 14 is rotatably connected to the vehicle body 2. Bucket 12 is operated by power generated by bucket cylinder 14. Bucket cylinder 14 is an actuator that generates power to move bucket 12. When the operator operates the bucket operating lever 34 (FIG. 2), the bucket cylinder 14 expands and contracts. This causes the bucket 12 to swing. The bucket cylinder 14 is, for example, a hydraulic cylinder. The cutting edge 12T has a shape such as a serpentine blade or a flat blade, and is replaceably attached to the end of the bucket 12.

[Control system configuration]
FIG. 2 is a block diagram showing a configuration example of a control system for the wheel loader 1 according to the present embodiment. As shown in FIG. 2, the wheel loader 1 includes a power source 201, a PTO (Power Take Off) 202, a hydraulic pump 203, a control valve 200, an operating device 32, a display input section 35, and an output section 36. and a controller 100.

The power source 201 generates driving force for operating the working machine. Examples of the power source include an internal combustion engine and an electric motor.

The PTO 202 transmits at least a portion of the driving force of the power source 201 to the hydraulic pump 203. The PTO 202 distributes the driving force of the power source 201 to the traveling device 4 and the hydraulic pump 203.

The hydraulic pump 203 is driven by the power source 201 and discharges hydraulic oil. At least a portion of the hydraulic fluid discharged from the hydraulic pump 203 is supplied to each of the boom cylinder 13 and the bucket cylinder 14 via the control valve 200. Control valve 200 receives a predetermined control signal from controller 100 and controls the flow rate, pressure, and direction of hydraulic oil supplied from hydraulic pump 203 to boom cylinder 13 and bucket cylinder 14, respectively. The work machine 10 operates using hydraulic oil from a hydraulic pump 203.

The operating device 32 is arranged inside the cab 3. The operating device 32 is operated by an operator. The operator operates the operating device 32 to adjust the traveling direction and traveling speed of the wheel loader 1, to switch between forward and backward movement, and to operate the work implement 10. The operating device 32 includes, for example, a steering wheel, a shift lever, an accelerator pedal, a brake pedal, a boom operating lever 33, and a bucket operating lever 34. The boom operating lever 33 is an operating lever for operating the attitude of the boom 11. The boom operating lever 33 has a main angle sensor 331 and a sub-angle sensor 332, and outputs two systems of detection signals indicating the amount of tilting of the operating lever. The bucket operating lever 34 is an operating lever for operating the attitude of the bucket 12. The bucket operating lever 34 has a main angle sensor 341 and a sub-angle sensor 342, and outputs two systems of detection signals indicating the amount of tilting of the operating lever.

Note that the boom operation lever 33 and the bucket operation lever 34 are collectively referred to as an operation lever. The main angle sensor 331, the sub-angle sensor 332, the main angle sensor 341, and the sub-angle sensor 342 are collectively referred to as an angle sensor. Moreover, when the main angle sensor 331 and the main angle sensor 341 are collectively referred to as a main angle sensor. Furthermore, when the sub-angle sensor 332 and the sub-angle sensor 342 are collectively referred to as a sub-angle sensor. The angle sensor detects the amount of tilt of the operating lever and outputs a detection signal indicating the detection result as an analog voltage value. The amount of tilting can be expressed as a value depending on the tilting angle, the amount of movement of the gripping portion, etc., for example. Note that the angle sensor can be configured from, for example, a combination of a variable resistor (potentiometer) and a signal processing circuit, a combination of a Hall element and a signal processing circuit, or the like. Furthermore, each detection signal is set so that the total value of the voltage value of the detection signal of the main angle sensor and the voltage value of the detection signal of the sub-angle sensor is a constant value. Furthermore, hereinafter, the main angle sensor may be simply referred to as main, and the sub angle sensor may simply be referred to as sub.

The display input unit 35 is composed of a combination of an input device and a display device, an input display device such as a touch panel, and the like. The operator uses the display input section 35 to input, for example, setting values for controlling the work machine 10. The output unit 36 includes a display device, a synthesized voice, an output device for an alarm sound or a notification sound, an indicator light such as a warning light, etc., and outputs predetermined information.

Note that the main angle sensor is an example of the first tilt amount sensor according to the present disclosure. Furthermore, the sub-angle sensor is an example of the second tilt amount sensor according to the present disclosure.

3 and 4 are cross-sectional views showing the boom operating lever 33 and bucket operating lever 34 according to the present embodiment. The boom operation lever 33 and the bucket operation lever 34 can have the same configuration, and the boom operation lever 33 will be described below as an example. FIG. 3 shows a case where the tilted position of the boom operating lever 33 is a neutral position, and FIG. 4 shows a case where the tilted position of the boom operating lever 33 has reached the rearward stroke end. Note that the boom operating lever 33 similarly tilts forward. The boom operating lever 33 has a mechanism that automatically returns the operating lever to a neutral position when no operating force above a certain level is applied to the operating lever. In this embodiment, the angle sensor is provided below the operating lever and detects the amount of tilt of the operating lever. A spring 301 is provided at the tilting center of the operating lever. The spring 301 has a function of automatically returning the position of the operating lever to the neutral position. A detent solenoid 302 is provided below the operating lever. The detent solenoid 302 has a function of holding the operating lever at the maximum tilted position even if the operating lever is released when the operating lever is tilted to the maximum when a current flows through the detent solenoid 302. The operating lever according to the present embodiment is an operating lever of the working machine 10 that tilts from a neutral position in a first direction (eg, forward direction) or in a second direction (eg, backward direction) opposite to the first direction.

FIG. 5 is an output characteristic diagram of the angle sensor according to the embodiment of the present disclosure. The horizontal axis is the output voltage, and the vertical axis is the operating lever stroke. In this case, the operating lever stroke is expressed as a percentage when the stroke end is "1". Further, assuming that the neutral position is "0%", for example, a case where the device is tilted forward is represented by a negative value, and a case where the device is tilted backward is represented by a positive value. However, the positive and negative directions may be reversed. The voltage value V1 is, for example, "0V", and the voltage value V5 is, for example, "5V". In this embodiment, the range of the signal voltage in the controller 100 is 0 to 5V DC. The voltage value V2 is a voltage for determining a ground fault, and the voltage value V4 is a voltage for determining a power fault. If the voltage of the detection signal output by the angle sensor is lower than V2, it can be determined that a ground fault has occurred. If the voltage of the detection signal output by the angle sensor is equal to or higher than V4, it can be determined that a short-to-power fault has occurred. Note that the range of the detection signal of the angle sensor is smaller than the range of voltage value V2 to voltage value V4. Further, the voltage value V3 is a voltage corresponding to the neutral position, and is, for example, "2.5V". In this example, the total value of the voltage value Vm of the detection signal of the main angle sensor and the voltage value Vs of the detection signal of the sub-angle sensor is constant, for example, "5V". In FIG. 5, the solid line indicates the voltage value Vm of the detection signal of the main angle sensor, and the dashed line indicates the voltage value Vs of the detection signal of the sub-angle sensor. Note that the output characteristic shown by the two-dot chain line is an example when the output characteristic shown by the solid line drops due to some kind of malfunction. For example, if the voltage value of the detection signal of the main angle sensor drops to Vm', the sum of Vm' and Vs will fall below 5V.

The controller 100 is configured using, for example, an FPGA (Field Programmable Gate Array) or a microcomputer that includes a processor, a main memory device, an auxiliary memory device, an input/output device, and the like. The controller 100 includes an acquisition unit 101 and a control unit 102 as a functional configuration composed of hardware or a combination of hardware and software such as a program. The controller 100 of this embodiment drives and controls the boom cylinder 13 and the bucket cylinder 14 by controlling the control valve 200 in accordance with the operation of the operating device 32 and the like. Controller 100 is an example of a control device according to the present disclosure.

The acquisition unit 101 acquires each detection signal (first detection signal) outputted by the main angle sensor according to the tilting amount of the operating lever, and each detection signal (second detection signal) outputted by the sub-angle sensor depending on the tilting amount of the operating lever. Detection signal) is repeatedly acquired, for example, at a predetermined period (for example, a period of several milliseconds to several hundred milliseconds).

For example, the control unit 102 determines whether each detection signal is normal or abnormal based on the detection signal of the main angle sensor and the detection signal of the sub-angle sensor, or determines whether each detection signal is normal or abnormal based on the detection signal of which angle sensor if it is abnormal. It also selects whether to control the control valve 200. Note that the control unit 102 determines whether there is an abnormality in the following two ways. One is that when the key of wheel loader 1 is turned on (when wheel loader 1 is started), each detection signal has a value indicating that the operation lever is in the neutral position, assuming that the operation lever is not operated. This is to determine whether or not there is. This judgment is called a neutral judgment. Note that the key-on time is a period of time shorter than the time normally required from turning on the key to starting operation of the operating lever, for example, from several seconds to more than ten seconds after turning on the key. The other determination is whether the sum of the voltage values of the main and sub detection signals is a predetermined constant value. This determination is called sum determination or error determination. The sum judgment can be made not only at the time of startup but also during operation of the operating lever.

For example, when the wheel loader 1 is turned on (starting up), the control unit 102 determines that the detection signal of the main angle sensor (first detection signal) and the detection signal of the sub-angle sensor (second detection signal) correspond to the neutral position. If both the first detection signal and the second detection signal have values corresponding to the neutral position, a predetermined control signal for controlling the working machine 10 based on the first detection signal is sent. Generate and output. Further, for example, if either the first detection signal or the second detection signal does not have a value corresponding to the neutral position, the control unit 102 generates a control signal based on the other first detection signal or second detection signal. At the same time, the output unit 36 outputs predetermined information corresponding to the case where one of the values does not correspond to the neutral position. Note that, in the example shown in FIG. 5, the value corresponding to the neutral position is a voltage value within the voltage value V3±α. Here, α is a voltage value within the permissible range for determination. In addition, the output of predetermined information includes, for example, displaying an error code indicating that the value does not correspond to the neutral position, notifying that an abnormality has been detected using synthesized voice or electronic sound, lighting or blinking a predetermined indicator light, etc. It is. Note that outputting the predetermined information is also referred to as error reporting.

Further, for example, when either the first detection signal or the second detection signal does not have a value corresponding to the neutral position, the control unit 102 controls the work equipment 10 based on the other first detection signal or second detection signal. Generates and outputs control signals with limited functionality. Restrictions on the functions of the work equipment 10 refer to restrictions on the action or operation of the work equipment 10, such as limiting the operating speed of the work equipment 10 to a value lower than normal (for example, about several to several tens of percent of the normal speed). It is.

For example, when the control unit 102 determines that both the first detection signal and the second detection signal have values corresponding to the neutral position, the total value of the first detection signal and the second detection signal is a constant value. If it is not a constant value, a control signal is generated and output to stop the operation of a predetermined actuator of the working machine 10. Here, the constant value is a voltage value within the double voltage value V3±β described with reference to FIG. Further, β is a voltage value within an allowable range for determination.

Further, the control unit 102 controls the detection signal (first detection signal) of the main angle sensor and the detection signal (second detection signal) of the sub-angle sensor to be at the neutral position, for example, when the wheel loader 1 is turned on (at startup). For example, it is repeatedly determined for a predetermined period of time from the key-on time whether the values correspond to each other. The predetermined time can be, for example, about several seconds to ten-odd seconds. If both the first detection signal and the second detection signal do not have values corresponding to the neutral position, the control unit 102 outputs a warning to that effect from the output unit 36. Furthermore, when both the first detection signal and the second detection signal reach a value corresponding to the neutral position before a predetermined period of time has elapsed, the control unit 102 stops outputting the alarm and adjusts the first detection signal to the value corresponding to the neutral position. Based on the control signal, a control signal for controlling the working machine 10 is generated and output. In addition, alarm outputs include, for example, displaying an error code indicating that the control lever is not in the neutral position, notification by synthesized voice or electronic sound that the control lever is not in the neutral position, and notification that the control lever is not in the neutral position. This includes lighting or blinking of a predetermined indicator light.

[Example of controller operation]
FIG. 6 is a state transition diagram showing an example of the operation of the controller according to the embodiment of the present disclosure. 7 to 10 are schematic diagrams for explaining operation examples of the controller according to the embodiment of the present disclosure. FIG. 6 shows the transition of states (states S0 to S8) in which the control unit 102 determines whether there is an abnormality based on the detection signal of the main angle sensor and the detection signal of the sub-angle sensor. The state transition shown in FIG. 6 starts when the key is turned on. The initial state is state S0.

In state S0, an initial check is performed by the control unit 102 to determine which of states S1 to S4 to transition to next. Based on the result of the initial check, the state transitions from state S0 to one of states S1 to S4. Note that the selection of the main angle sensor and sub angle sensor in state S0 is main. FIG. 7 shows the contents of the initial check. The control unit 102 performs neutrality determination in state S0. The control unit 102 performs the main/sub neutral determination after T5 time (for example, 0.3 seconds) has elapsed from the time of startup, and after T6 time (for example, 0.5 seconds) has elapsed. The control unit 102 determines that the vehicle is neutral if it is always within the neutral range for the time T6. Further, the control unit 102 determines that the vehicle is non-neutral if the vehicle is outside the neutral range even once during T6 time.

In state S0, if condition 1 is satisfied, the state transitions to state S1. In state S0, if condition 2 is satisfied, the state transitions to state S2. In state S0, if condition 3 is satisfied, the state transitions to state S3. In state S0, when condition 4 is satisfied, a transition is made to state S4. FIG. 8 shows a list of conditions 1 to 7.

The conditions for condition 1 to hold are that condition 2 is not held, condition 3 is not held, and condition 4 is not held.

Condition 2 is satisfied if the main is neutral, the sub is non-neutral, and both the main and sub are not within the error detection range of disconnection, ground fault, or power fault. Note that disconnection can be determined based on whether the output signal line of each sensor is in a high impedance state.

Condition 3 is satisfied if the main is non-neutral, the sub is neutral, and both the main and sub are not within the error detection range of disconnection, ground fault, or power fault.

Condition 4 is satisfied if the main is non-neutral, the sub is non-neutral, and both the main and sub are not within the error detection range of disconnection, ground fault, or power fault.

State S1 is a state in which both the main and sub are normal (normal). The main and sub selection is the main one. The error output is a no-error state (no error notification or alarm). When condition 7 continues to hold for a time T1 (for example, 0.05 seconds) in state S1, a transition occurs from state S1 to state S6.

State S2 is a state in which the sub is abnormal. The main and sub selection is the main one. The error output is an error notification. The working machine 10 has limited functionality. State S2 is maintained until the key is turned off.

State S3 is a state in which the main is abnormal. The main and sub selection is sub. The error output is an error notification. The working machine 10 has limited functionality. State S3 is maintained until the key is turned off.

State S4 is a state in which both the main and sub are abnormal. The output of an error is an alarm. State S4 transitions to state S0 when condition 5 is satisfied, and transitions to state S5 when condition 6 is satisfied.

The condition for condition 5 is that both the main and sub are neutral for at least T3 time (for example, 0.5 seconds). When performing this transition, the control unit 102 changes the initial check results to neutral for both the main and sub.

The condition for condition 6 to be established is that T4 time (for example, 10 seconds) has elapsed after the transition to state S4.

Condition 7 is that the total voltage value of the main and sub is outside the range of 2×V3±β, and both the main and sub are not within the error detection range of disconnection, ground fault, or power fault.

State S5 is a state in which both the sub and main are abnormal. The main and sub selection is the main one. The error output is an error notification. The working machine 10 has limited functionality. State S5 transitions to state S7 when condition 7 is satisfied for time T1.

State S6 is a state in which one or both of the sub and main is abnormal. The main and sub selection is the main one. There is no error output. In the working machine 10, the operation of a predetermined actuator is stopped. State S6 transitions to state S1 when condition 7 is not satisfied, and transitions to state S8 when condition 7 is satisfied for T2 time (for example, 1 second).

State S7 is a state in which both the sub and main are abnormal. The main and sub selection is the main one. The error output is an error notification. In the working machine 10, the operation of a predetermined actuator is stopped. State S7 transitions to state S6 when condition 7 is not satisfied, and transitions to state S8 when condition 7 is further satisfied for time T2.

State S8 is a state in which one or both of the sub and main is abnormal. The main and sub selection is the main one. The error output is an error notification. In the working machine 10, the operation of a predetermined actuator is stopped. State S8 is maintained until the key is turned off.

In the state transition shown in FIG. 6, in states S2 and S3, even if either the main or sub is non-neutral, if one is normal, the work implement 10 can be moved, so emergency operation is possible. Furthermore, since the error is reported, repair is prompted, and the possibility that the other angle sensor also malfunctions (double failure) can be reduced. In this embodiment, emergency operation means operation of the work machine 1 while maintaining the minimum functions in an emergency such as a failure, and for example, when the work machine 1 is running on the work machine 10. This is operation in a state in which the working machine 1 is driven to a possible state and maintains the functions necessary to move the working machine 1 to a place where repair can be performed.

In addition, in state S4, an alarm (for example, an erroneous operation alarm (not a failure)) is issued in case of an erroneous operation when the key is turned on, and a failure is determined if an abnormality is determined for T4 time or more.

In state S8, in the case of a sum error, safety is ensured by forcibly stopping the working machine 10. When it is desired to operate in an emergency, by turning the key on from the key-off state, the state transitions to, for example, state S2, and if one sensor is not malfunctioning, the work implement 10 can be moved.

FIG. 9 collectively represents the operation of the controller 100 described with reference to FIG. 6. Regarding neutral determination or error determination, "〇" indicates normality, and "x" indicates abnormality. Regarding emergency operation, "〇" indicates that the attitude of the work implement 10 is driven to a state in which it can travel, and it can be operated in an emergency, and "△" indicates that it can be operated in an emergency, depending on the case.

FIG. 10 summarizes the operation when the failure progresses from the normal state (No. 1) shown in FIG. 9. If the voltage of the detection signal of one or both of the angle sensors drops, the error determination becomes abnormal and the working machine 10 is stopped. Therefore, even if the neutral judgment becomes abnormal, the work machine 10 will be stopped, so the work machine 10 will not move with the operator's hand released from the operating lever. Therefore, safety can be ensured (“〇”).

(action/effect)
According to the present embodiment, when an abnormality occurs in the detection of the tilting amount of the operating lever of the working machine, it is possible to appropriately deal with it.

<Modifications of this embodiment or other embodiments>
Although the embodiments of the present invention have been described above with reference to the drawings, the specific configuration is not limited to the above-described embodiments, and may include design changes without departing from the gist of the present invention. Furthermore, part or all of the program executed by the computer in the above embodiments can be distributed via a computer-readable recording medium or a communication line.

For example, the wheel loader 1 may be remotely controlled. In this case, part or all of the controller 100 and the operating device 32 can be provided at a location where remote control is performed, for example.

Further, for example, the working machine (or working vehicle) is not limited to a wheel loader, and may be any working machine that includes a working machine that is driven in accordance with the operation of the operating lever. For example, it may be another working machine such as a hydraulic excavator. Further, the work tool is not limited to a bucket. The working tool may be, for example, a fork, bale grab, etc. that is replaceably attached to the wheel loader as an attachment.

<Additional notes>
The controller 100 (control device) described in the above embodiment can be understood as follows, for example.

(1) The controller 100 (control device) is a control device for the work machine 1 including the work machine 10, and is used for the task of tilting from a neutral position in a first direction or a second direction opposite to the first direction. A first detection signal outputted by a first tilt amount sensor (main stroke sensor) that detects the tilt amount of the operating lever of the machine in accordance with the tilt amount, and a second tilt amount sensor (sub stroke sensor) that detects the tilt amount. ) that repeatedly obtains a second detection signal outputted by the operator according to the tilting amount; and an acquisition unit 101 that repeatedly obtains a second detection signal outputted by the work machine according to the tilting amount; It is repeatedly determined for a predetermined period of time whether or not the detection signal exists, and if both the first detection signal and the second detection signal do not have values corresponding to the neutral position, a predetermined output unit 36 outputs an alarm to that effect, and the When both the first detection signal and the second detection signal reach values corresponding to the neutral position before a predetermined period of time has elapsed, the output of the alarm is stopped, and the output of the alarm is stopped based on the first detection signal. The control unit 102 generates and outputs a predetermined control signal for controlling the working machine.

(2) If either the first detection signal or the second detection signal does not have a value corresponding to the neutral position, the control unit 102 is configured to control the control unit 102 based on the other first detection signal or second detection signal. In the control device according to (1), the control device generates and outputs the control signal, and outputs predetermined information corresponding to the case where the one of the values does not correspond to the neutral position from a predetermined output section.

(3) If either the first detection signal or the second detection signal does not have a value corresponding to the neutral position, the control unit 102 is configured to control the control unit 102 based on the other first detection signal or second detection signal. The control device according to (2) generates and outputs the control signal after restricting the functions of the work machine.

1...Wheel loader (work machine), 2...car body, 3...cab, 4...travel device, 5...wheel, 6...tire, 10...work machine, 11...boom, 12...bucket (work tool), 12T...cutting edge , 13... Boom cylinder, 14... Bucket cylinder, 15... Bell crank, 16... Link, 17... Movable support section, 32... Operating device, 33... Boom operating lever, 34... Bucket operating lever, 331, 341... Main stroke sensor , 332, 342... Substroke sensor, 100... Controller (control device), 101... Acquisition unit, 102... Control unit

Claims

A control device for a work machine including a work machine,
A first tilt amount sensor that detects a tilt amount of an operating lever of the working machine that is tilted from a neutral position in a first direction or a second direction opposite to the first direction outputs a first tilt amount according to the tilt amount. an acquisition unit that repeatedly acquires a detection signal and a second detection signal output by a second tilt amount sensor that detects the tilt amount according to the tilt amount;
repeatedly determining for a predetermined time whether the first detection signal and the second detection signal have values corresponding to the neutral position when the working machine is started;
If both the first detection signal and the second detection signal do not have values corresponding to the neutral position, outputting an alarm to that effect from a predetermined output section;
When both the first detection signal and the second detection signal reach values corresponding to the neutral position before the predetermined time elapses, the output of the alarm is stopped, and the output of the alarm is stopped based on the first detection signal. a control unit that generates and outputs a predetermined control signal for controlling the working machine.
When either the first detection signal or the second detection signal does not have a value corresponding to the neutral position, the control unit adjusts the control signal based on the other first detection signal or second detection signal. The control device according to claim 1, wherein the control device generates and outputs a value, and outputs predetermined information corresponding to a case where the one value is not a value corresponding to the neutral position from a predetermined output unit.
When either the first detection signal or the second detection signal does not have a value corresponding to the neutral position, the control unit controls the operation based on the other first detection signal or second detection signal. The control device according to claim 2, wherein the control signal is generated and output after restricting the functions of the device.
A method for controlling a working machine including a working machine, the method comprising:
A first tilt amount sensor that detects a tilt amount of an operating lever of the working machine that is tilted from a neutral position in a first direction or a second direction opposite to the first direction outputs a first tilt amount according to the tilt amount. repeatedly acquiring a detection signal and a second detection signal output by a second tilt amount sensor that detects the tilt amount according to the tilt amount;
repeatedly determining for a predetermined time whether the first detection signal and the second detection signal have values corresponding to the neutral position when the working machine is started;
If both the first detection signal and the second detection signal do not have values corresponding to the neutral position, outputting an alarm to that effect from a predetermined output section;
When both the first detection signal and the second detection signal reach values corresponding to the neutral position before the predetermined time elapses, the output of the alarm is stopped, and the output of the alarm is stopped based on the first detection signal. and generating and outputting a predetermined control signal for controlling the working machine.
work equipment and
A first tilt amount sensor that detects a tilt amount of an operating lever of the working machine that is tilted from a neutral position in a first direction or a second direction opposite to the first direction outputs a first tilt amount according to the tilt amount. an acquisition unit that repeatedly acquires a detection signal and a second detection signal output by a second tilt amount sensor that detects the tilt amount according to the tilt amount;
repeatedly determining for a predetermined time whether the first detection signal and the second detection signal have values corresponding to the neutral position when starting the working machine;
If both the first detection signal and the second detection signal do not have values corresponding to the neutral position, outputting an alarm to that effect from a predetermined output section;
When both the first detection signal and the second detection signal reach values corresponding to the neutral position before the predetermined time elapses, the output of the alarm is stopped, and the output of the alarm is stopped based on the first detection signal. and a control section that generates and outputs a predetermined control signal for controlling the work machine.