JPH04140505A - Diagnostic device for hydraulic circuit electronic control device - Google Patents

Abstract

PURPOSE:To enable quick repair by previously detecting the abnormal condition of a sensor detected by a data collecting means of an electronic controller to indicate the condition in a form understandable for men with an indicator. CONSTITUTION:An abnormal condition signal and sensor input signal inputted from an electronic control unit 11 by communication are indicated on an indicator 12. When communication data from the indicator are 'P', the electronic control unit communicates a pressure signal P to the indicator. Then the pressure signal P is received as communication data. Next, the pressure signal P is converted according to a converting method preset on a program of the indicator to be indicated on the indicator. That is, while the pressure signal is inputted as a voltage signal, it is converted to a pressure unit to be indicated so that an operator can easily understand it.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a diagnostic device for a hydraulic circuit electronic control device used in a hydraulic machine such as a hydraulic excavator or a hydraulic crane.

[Conventional technology]

In recent years, in construction machinery driven by a hydraulic drive device, such as a hydraulic excavator and a hydraulic crane, electronic control has been progressing in order to improve the control system of the hydraulic drive device. 8th
The figure shows an example of a conventional electronic control device for a hydraulic circuit. In the figure, 1 is a hydraulic pump, which is driven by a prime mover (not shown) and discharges hydraulic pressure. Reference numeral 1a denotes a variable discharge amount mechanism (hereinafter referred to as a swash plate) of the hydraulic pump, and the discharge amount of the hydraulic pump changes depending on its position. 2 is a hydraulic actuator driven by pressure oil discharged from the hydraulic pump 1; 3 is an operating lever 4 interposed between the hydraulic pump 1 and the hydraulic actuator 2;
This is a flow control valve that adjusts the amount of pressurized oil to the hydraulic actuator and the flow direction according to the amount of operation of the hydraulic actuator. Reference numeral 5 denotes a servo piston that drives the swash plate, and a solenoid valve 8 allows hydraulic pressure to flow from a hydraulic pressure source 6 to the left and right sides of the piston or return to a tank 7.
a.

The piston moves by switching by 8b.

A tilt angle sensor 9 detects the position of the swash plate, and is composed of a displacement sensor such as a potentiometer. 10
is a pressure sensor that detects the pressure of the pressure oil discharged by the hydraulic pump. IIA is an electronic control unit that controls the solenoid valve 8 based on information from the pressure sensor 10 and the tilt angle sensor.
a and 8b to control the position of the swash plate 1a of the hydraulic pump 1.

Details of the electronic control unit (IIA) are shown in FIG.

The electronic control unit IIA is composed of a microcomputer, and includes an A/D converter 11a that converts the tilt angle signal θ output from the tilt angle sensor 9 and the pressure signal P output from the pressure sensor 10 into digital signals; A central processing unit (CPU) 1lb, a read-only memory (ROM) 11c that stores control procedure programs, and a random access memory (R) that temporarily stores numerical values during calculations.
AM) lid and output to solenoid valves 8a and 8b (7) I
10 interfaces lle.

Figure 10 shows the ROMI of the conventional electronic control unit 11A.
1 shows a flowchart of the control means stored in c. Hereinafter, a conventional example will be explained according to the control means shown in FIG.

First, in the means 100 of FIG.
The pressure signal P of 0 and the tilt angle signal θ of the tilt angle sensor are expressed as A/
It is input via a D converter and stored in RAM1id. Next, in step 200, the target position θr of the swash plate 1a of the hydraulic pump 1 is calculated.

The calculation calculates θT from the relationship between the pressure signal P shown in FIG. 11 and the swash plate target position θr so that the absorption torque of the hydraulic pump does not exceed a certain value so that the prime mover that drives the hydraulic pump does not become overloaded. Next, in step 300, control is performed so that the actual swash plate position θ matches the swash plate target position θT calculated in step 200. The detailed procedure is explained in the 12th section.
As shown in the figure.

First, in step 301, the deviation 2 between the swash plate target position θr and the actual swash plate position θ is calculated. Next, in step 302, it is determined whether the absolute value of deviation 2 is greater than or equal to the dead zone Δ. When the deviation Z is smaller than the dead zone Δ, it is assumed that the swash plate position θ matches the target value θr, and in step 303, the solenoid valve 8a,
8b is turned OFF to cut off the flow of pressure oil to both sides of the servo piston 5, and the swash plate is stopped at that position. If the deviation Z is larger than the dead zone Δ in step 302, the process goes to step 304.

In step 304, the sign of the deviation Z is determined.

If the deviation Z is positive, go to step 305 and turn the solenoid valve 8a to O.
N, turn 8b OFF. Pressure oil then flows to both sides of the servo piston. Here, since the cross-sectional area of the servo piston is larger on the right side in the figure, the servo piston moves to the left, and the swash plate position increases. If it is determined in step 304 that the deviation 2 is negative, the process proceeds to step 306. Step 3
At 06, the solenoid valve 8a is turned off and the solenoid valve 8b is turned on.

Then, the hydraulic pressure flows into the left side of the servo piston as shown in the figure, and the right side connects to the tank and oil flows out. As a result, the servo piston 5 moves to the right and the tilted position becomes smaller. Upon completion of step 300, the process returns to step 100, and the above steps are repeated.

As described above, the electronic control unit IIA controls the hydraulic pump according to the pressure signal so that the absorption torque does not exceed a certain level.

[Problem to be solved by the invention]

However, this conventional hydraulic circuit electronic control device has the following problems.

In the electronic control device having this structure, for example, if the wiring of the pressure sensor 10 is disconnected, the electronic control unit 11A
is input as a pressure signal Ov, and the electronic control unit determines it to be the lowest pressure in step 200 and calculates the maximum target position.

As a result, the hydraulic pump is not controlled below a certain torque, and the prime mover becomes overloaded, which impedes the operation of the vehicle body. To repair this condition, it is first necessary to discover which component in the electronic control system of this hydraulic circuit is at fault. Therefore, other pressure gauges and flow meters are inserted into the hydraulic circuit to determine the status of the hydraulic circuit, and then a tester is used to check the output to each sensor and solenoid valve. Then, we have no choice but to take the extremely time-consuming method of discovering the pressure sensor's disconnection.

If the sensor is disconnected, it is easy to detect because the output becomes OV, but if the tilt angle sensor 9 comes off the swash plate, the sensor output stops at a halfway point instead of OV. However, it is not possible to tell if the sensor is defective until after intentionally operating the machine to change the pressure and checking with a flow meter whether the flow rate changes. In such a state, repairs take time, and in the case of production materials such as construction machinery, it causes great inconvenience to customers. Repairs also require knowledge of both hydraulics and electronic control, and require considerable skill. In addition, inserting other measuring devices into the hydraulic circuit to detect failures may cause dirt, debris, etc. to enter the hydraulic circuit when the piping is removed, which may cause other failures.

An object of the present invention is to provide an electronic control device for a hydraulic circuit, in order to quickly repair the failure in the event of a failure, and to quickly find a failure point without inserting another measuring device into the hydraulic circuit.
An object of the present invention is to provide a diagnostic device that can check the status of a sensor connected to an electronic control device.

[Means to solve the problem]

In order to achieve the above object, the present invention includes a first means for detecting an abnormal state such as a sensor input in an electronic control device that controls a hydraulic circuit, and a first means for communicating and outputting the abnormal state signal and the input sensor signal. a third means for communicatively inputting an abnormal state signal such as a sensor input and the input sensor signal from the data collecting means; and third means for displaying the detected sensor signal.

The display means preferably includes a fifth means for inputting from a keyboard or the like, and displays either an abnormal state signal such as a sensor input or an input sensor signal to the data collection means according to the input from the fifth means. and a sixth means for instructing the third means to select and output the communication.

Further, the display means preferably instructs the data collection means to output an abnormal state signal such as a sensor input, and when the signal is inputted by the third means, the abnormal state signal is displayed. The apparatus further includes seventh means for determining the signal and causing the fourth means to display a preset display text corresponding to the signal.

Preferably, the display means instructs the data collection means to communicate the input sensor signal, and when the signal is input by the third means, the display means is configured in advance to communicate the input sensor signal. The apparatus further includes eighth means for converting the sensor signal using a conversion method according to the present invention and displaying the converted sensor signal on the fourth means.

[Effect]

In the present invention configured in this way, an abnormal state of the sensor that can be detected by the data collection means of the electronic control device is detected in advance, and the state is outputted to the display means through communication and displayed in a form that is easy for humans to understand. , detect abnormal conditions without inserting any other measuring device into the hydraulic circuit, and
Even non-skilled workers can immediately know and perform repairs quickly.

In addition, even in abnormal conditions that cannot be detected by the data collection means, the sensor human input signal can be displayed and confirmed by the display means, so it is possible to determine the abnormal state of the sensor without inserting any other measuring device into the hydraulic circuit. It's also easy to do.

In the above operation, there is no need to insert any other measuring device into the hydraulic circuit, so it is possible to prevent dirt, debris, etc. from entering the hydraulic circuit when the piping of the hydraulic circuit is removed.

In addition, the data that is communicated and output from the data collection means to the display means is only the abnormal state signal and the sensor human input signal, and the processing of displaying text that is easy to understand for the operator or converting and displaying the data is necessary. By using the display device, the processing for diagnosing the electronic control unit can be reduced, and the communication data can also be reduced, so that no burden is placed on the original control processing.

Furthermore, when the sensor is operating normally, the hydraulic circuit can be easily diagnosed using the sensor signal.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

FIG. 1 shows an embodiment of the present invention. In the figure, the same components as in FIG. 8 are indicated by the same numbers. In the figure, 11 is an electronic control unit according to the present invention, and 12 is an electronic control unit 11.
This is a display device that is connected to the electronic control unit and inputs abnormal status signals and sensor human input signals via communication and displays them.

FIG. 2 shows details of the electronic control unit 11 and display device 12. In the figure, the same components in the electronic control unit 11 as in the electronic control unit 11A shown in FIG. 9 are indicated by the same numbers. llf is the communication interface (1/F
), it communicates and outputs data input from the CPU 11a, and outputs data input from the outside to the CPU 11a. Serial communication, which requires fewer wires, is generally used for communication. The display device 12 is also composed of a microcomputer, and the keyboard 12
A keyboard interface (1/F) 12a that inputs signals from b and outputs them to the CPU 12C, a central processing bag (
if (CPU) 12 cl Display interface (I/F) 12d1 that displays display data input from CPUI 2c on display 12e ROM 12f that stores programs, RA that temporarily stores numerical values during calculations
A communication interface 12h is provided for outputting data from the M12g10PUI2C to the electronic control unit 11 and outputting communication data from the electronic control unit 11 to the CPU 12c.

FIG. 3 shows a flowchart of the control procedure stored in the ROM 11c of the electronic control unit 11, and FIG. 6 shows the control procedure stored in the ROM 12f of the display device 112.

The operation of this embodiment will be described in detail below with reference to FIGS. 3 to 6.

First, in FIG. 3, steps 100, 200, and 300 are similar to the control steps of the conventional electronic control unit described above, and the swash plate position of the hydraulic pump 1 is controlled up to this point.

Next, in step 400, it is determined whether there is an abnormality in the sensor's human power. The details are shown in FIG. First, in step 401, it is determined whether the pressure signal P is Ov. If it is 0■, it is determined that the sensor power is disconnected and the process goes to step 402.
, set the error code of the pressure signal P to “1°”,
Go to step 406.

If it is determined in step 401 that it is not Ov, step 403
go to In step 403, it is determined whether the pressure signal P has reached the power supply voltage. If it is the power supply voltage, it is determined that the sensor power is short-circuited, and in step 404, the error code of the pressure signal P is set to '2'', and step 40
Go to 6. If the pressure signal is not the power supply voltage in step 403, the sensor determines that there is no disconnection or short circuit, and sets the error code of the pressure signal P to "0°" in step 4.
Go to 06.

From step 406, an abnormality determination is made with respect to the tilt angle signal θ. First, in step 406, it is determined whether θ is not 0■. If it is 0■, it is determined that the sensor power is disconnected,
In step 407, the error code of the tilt angle signal θ is set to 4'.
and go to step 500. If it is determined in step 406 that it is not OV, the process goes to step 408 and it is determined whether the tilt angle signal θ is not the power supply voltage. If the supply voltage is
Determining that the sensor power is short-circuited, go to step 409, set the error code of the tilt angle signal θ to 5, and proceed to step 50.
Go to 0. If it is determined in step 408 that the voltage is not the power supply voltage, the sensor manually determines that there is no disconnection or short circuit and sets the error code of the tilt angle signal to "3" in step 410.
and go to step 500.

Next, returning to FIG. 3, the process goes to step 500. Step 500
data communication between display devices is performed at

FIG. 5 shows details of procedure 500. First, in step 501, it is determined whether there is any communication input from the display device 12 through the communication I/F. If there is no communication input, continue with step 500.
Exit and return to the start.

If there is a communication input from the display device 12, the process goes to step 502 and determines the command meant by the input communication data. Here, if the communication data is l E l , the process goes to step 503, and the error hoods of the pressure signal P and the tilting signal θ are read out. Then, the process goes to step 506. Step 5
If the data is determined to be “P” in 02,
Go to step 504, read out the pressure signal P, and go to step 506. If it is determined that the data is "To" in step 502, the process goes to step 505, reads the tilt angle signal θ, and goes to step 506. In step 506, the data read in each step is sent via the communication I/F. Display device 12
Output communication to. When step 500 is completed, the process returns to the start and repeat control is performed.

Next, a control procedure for the display device 12 shown in FIG. 6 will be explained. First, in step 600, keyboard input data is read from the keyboard I/F. Next, in step 601, the data previously input in step 600 is determined. Here, if the data entered from the keyboard is E',
Step 602 and subsequent steps are performed. Step 602 and subsequent steps are abnormal state displays. First, in step 602, data transmitted from the display device 12 to the electronic control unit 11 is assumed to be E'. Next, this data is output to the electronic control unit 11 through the communication 1/F. Next, in step 604, data is input via communication from the electronic control unit 11. In the control procedure of the electronic control unit 11 shown above, data E is used as a command.
' is received from the display device, the error code of the pressure signal and tilt angle signal is communicated to the display device. Therefore, in step 604, the error code is received as communication data.

Next, the process goes to step 605, and the content of the error is displayed based on the error code.

FIG. 7 shows details of step 605. First, step 605a
Check the error code of the pressure signal P input via communication. Here, if it is determined that the error code is "1°," the process goes to step 605b.

As shown in the control procedure 400 of the electronic control unit above, the error code "1" indicates a disconnection of the pressure sensor. Therefore, in step 605b, the message "Pressure sensor disconnection" is displayed on the display. And step 605
Go to f. In step 605a, the error code is 2'.
If it is determined that this is the case, the process goes to step 605c. Error code "2" indicates a short circuit in the pressure sensor, so proceed to step 60.
At 5C, the message "Pressure sensor short circuit" is displayed on the display. Then, the process goes to step 605f. Step 605a
If it is determined that the error code is "θ', it means that no abnormality was detected in the pressure sensor, and the process goes to step 605d. In step 605d, the error code of the tilt angle signal θ input via communication is determined. Here, if the error code is "3', it is determined that no abnormality was detected in the tilt angle sensor, and in step 605e, "
The display text "No abnormality" is displayed on the display and the process returns to the start. If the error code is "4' or 5°" in step 605d, the process proceeds to step 605f.

In step 605f, the error code of the tilt angle signal θ is determined. Here, if the error code is 3, it is determined that no abnormality in the tilt angle sensor has been detected, and the process returns to the start without displaying anything. If the error code is 4゛, it means that the tilt angle sensor is disconnected, so in step 605g, ``1 tilt angle sensor disconnected'' is displayed on the display, and the process returns to the start.In step 605f, the error code is ``5''. If it is determined that there is a short circuit in the tilt angle sensor, "Tilt angle sensor short circuit" is displayed on the display in step 605h, and the process returns to the start.

Returning to FIG. 6, if it is determined in step 601 that the key force is P, it is determined that a pressure signal is being displayed, and the process proceeds to step 607. In step 607, the communication data from the display device 12 to the electronic control unit 11 is set as P'.

Then, in step 608, the communication 1/F communicates with the electronic control unit. In step 500 previously shown in FIG. 5, the electronic control unit receives the communication data from the display device.
If P l , a pressure signal P is communicated to the display device. Therefore, in step 609, the pressure signal P is received as communication data. Next, in step 610, the pressure signal P is converted using a conversion method set in advance on the display program and displayed on the display. That is, although the pressure signal is input as a voltage signal, it is converted into a pressure unit, for example MPa, and displayed so that it is easy for the operator to understand.

Then return to the start.

If it is determined in step 601 that the key force is T°, it is determined that the tilt angle signal is displayed, and step 611 is performed.
go to In step 611, communication data from the display device 12 to the electronic control unit 11 is assumed to be T'. Then, in step 612, the communication 1/F communicates with the electronic control unit. In step 500 previously shown in FIG. 5, the electronic control unit communicates the tilt angle signal θ to the display device when the communication data from the display device is T′. Therefore, step 6
13, the tilt angle signal θ is received as communication data. Next, in step 614, the tilt angle signal θ is converted using a conversion method set in advance on the program of the display device,
Display on the display.

That is, although the tilting angle signal is input as a voltage signal, it is converted into an angular unit, for example, rad, and displayed so that it can be easily understood by the operator. Then return to the start.

After returning to the start, the process is repeated.

〔Effect of the invention〕

In the present invention configured as described above, the abnormal state of the sensor that can be detected by the data collection means of the electronic control device is detected in advance, and the abnormal state is displayed on the display means in a form that is easy for humans to understand. This can be immediately detected without inserting any other measuring device into the hydraulic circuit, and even unskilled workers can perform repairs quickly.

In addition, even in abnormal conditions that cannot be detected by the data collection means, the sensor human input signal can be displayed and confirmed by the display means, so it is possible to determine the abnormal state of the sensor without inserting any other measuring device into the hydraulic circuit. It's also easy to do.

In the above operation, there is no need to insert any other measuring device into the hydraulic circuit, so it is possible to prevent dirt, debris, etc. from entering the hydraulic circuit when the piping of the hydraulic circuit is removed.

In addition, the only data that is communicated from the data collection means to the display device is the abnormal state signal and the sensor human input signal, and the processing of displaying text that is easy for the operator to understand from these data, or converting and displaying the data is the display. By having the device perform this, the processing for diagnosing the electronic control device can be reduced, and the communication data can also be reduced, so there is no burden on the original control processing.

Furthermore, when the sensor is operating normally, the hydraulic circuit can be easily diagnosed using the sensor signal.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of a hydraulic circuit equipped with a diagnostic device and its electronic control device according to an embodiment of the present invention, FIG. 2 is a schematic diagram of an electronic control unit and a display device, and FIG.
FIG. 4 is a flowchart showing the control procedure performed by the electronic control unit, FIG. 3 is a flowchart showing details of the procedure for performing data communication to the display device, FIG. 6 is a flowchart showing the control procedure performed by the display device, and FIG. 7 is a flowchart showing the flowchart shown in FIG. 6. FIG. 8 is a schematic diagram of a hydraulic circuit equipped with a conventional electronic control device, and FIG. 9 is a schematic diagram of a conventional electronic control unit. , FIG. 10 is a flowchart showing the control procedure performed by the conventional electronic control unit, FIG. 11 is an explanatory diagram of the calculation of the target position of the swash plate of the hydraulic pump shown in FIG. 10, and FIG. 10 is a flowchart showing a control procedure for the swash plate position of the hydraulic pump shown in FIG. 10. FIG. Explanation of symbols 1...Hydraulic pump 1a...Swash plate 2...Hydraulic actuator 3...Flow rate control valve 4...Operation lever 5...Servo piston 6...Hydraulic source 7... Tanks 8a, 8b...Solenoid valve 9...Tilt angle sensor 10...Pressure sensor 11-...Electronic control unit (data collection means) 12...
... Display device (display means) 11a to lid, procedure 400 ... First means 11
f2 Procedure 500...Second means 12h...Third means 12a-12g9 Procedures 600-614...Fourth means

Claims (4)

[Claims] (1) Data comprising a first means for detecting an abnormal state such as a sensor input in an electronic control device that controls a hydraulic circuit, and a second means for communicating and outputting the abnormal state signal and the input sensor signal. a third means for communicatively inputting an abnormal state signal such as a sensor input and the input sensor signal from the data collecting means; and a third means for displaying the abnormal state signal such as the sensor input and the input sensor signal. 1. A diagnostic device for a hydraulic circuit electronic control device, characterized in that it has a display means having the following means. (2) The diagnostic device for a hydraulic circuit electronic control device according to claim 1, wherein the display means further includes a fifth means for inputting from a keyboard or the like, and a display means for displaying the data in accordance with the input from the fifth means. and a sixth means for instructing the third means to select and communicate and output either an abnormal state signal such as a sensor input or an input sensor signal. Equipment diagnostic equipment. (3) In the hydraulic circuit electronic control device diagnostic device according to claim 1, the display means further instructs the data collection means to output an abnormal state signal such as a sensor input, and transmits the signal. It is characterized by comprising a seventh means for determining the abnormal state signal when input by the third means and causing the fourth means to display a preset display text corresponding to the signal. A diagnostic device for hydraulic circuit electronic control equipment. (4) In the diagnostic device for a hydraulic circuit electronic control device according to claim 1, the display means further instructs the data collection means to communicate the input sensor signal, and transmits the signal to the third An electronic hydraulic circuit characterized in that it is provided with an eighth means for converting the sensor signal by a conversion method set in advance for the sensor signal when input by the means, and displaying the converted result on the fourth means. Diagnostic equipment for control equipment.