JPH0666302A - Electronic control device for hydraulic circuit - Google Patents

Abstract

(57) [Abstract] [PROBLEMS] To provide a configuration of a control unit in an electronic control device for a hydraulic circuit, in which wiring is simple, replacement is inexpensive, production control is easy, and there is no control mismatch or assembly error. [Structure] A control unit 11 that stores basic data performs data communication with the control units 7 and 12 in response to a signal from the control unit 10. The control unit 7 receives and inputs the basic data from the control unit 11 and performs a control calculation based on this and the pressure signal of the pressure detector 5 and the swash plate position signal of the swash plate detector 6 to the swash plate position control device 8. Output drive signal.
The discharge flow rate of the hydraulic pump 1 is controlled by this signal.
The control unit 12 receives / inputs basic data from the control unit 11, performs control calculation, and outputs a control signal to the motor 14. The opening of the governor lever 13b of the engine 13 is controlled by this signal, and the rotation speed of the engine 13 is controlled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic drive circuit used in a hydraulic machine such as a hydraulic excavator and a hydraulic crane, a control device such as a prime mover, and more particularly to a structure of an electronic control device having a plurality of control units.

[0002]

2. Description of the Related Art In recent years, in construction machines such as hydraulic excavators and hydraulic cranes that drive a working device by a hydraulic drive system, hydraulic pressure is used for the purpose of improving functionality, improving operability, and saving energy for adapting to various works. Electronic control of drive units and prime movers is being promoted. FIG. 25 shows an example of an electronic control device for a hydraulic circuit.

This electronic control unit includes a prime mover 13 such as an engine (hereinafter referred to as an engine), a hydraulic pump 1 driven by the engine 13, a hydraulic actuator 2 driven by pressure oil discharged from the hydraulic pump 1, and a hydraulic pressure. A control valve 3 connected between the pump 1 and the hydraulic actuator 2 for controlling the flow rate of pressure oil supplied to the hydraulic actuator 2, a control unit 17, and a control unit 18.
And a control unit 19.

The number of revolutions of the engine 13 is controlled by the governor 13a. The setting of rotation speed at this time is governor 1
This is done by changing the angle of the governor lever 13b built in 3a. The governor lever 13b is provided with a governor lever angle detector 15 that detects the angle of the governor lever 13b. A signal monitored by the governor lever angle detector 15 and a signal from the throttle lever 16 are transmitted to the control unit 19, and the control unit 19 drives the motor 14 based on these signals to control the angle of the governor lever 13b to thereby control the engine. The rotation speed of 13 is controlled.

In the hydraulic pump 1, signals from the pressure detector 5 and the swash plate position detector 6 are transmitted to the control unit 18,
The signal causes the control unit 18 to move the swash plate position control device 8
Through, the position of the swash plate 1a is controlled, and the displacement, that is, the discharge flow rate is controlled.

The control valve 3 receives a signal from the control unit 17 by the operating lever 4 and the solenoid valves 3L and 3R receive the signals to control the opening of the control valve 3 to control the direction and flow rate of the pressure oil to the actuator 2 or the tank 9. .

FIG. 26 shows the structure of the control unit 18.
The control unit 18 receives the pressure signal Pd from the pressure detector 5 and the swash plate position signal θ from the swash plate detector 6 and converts the A / D converter 20e into a digital signal, and a central processing unit (C).
PU) 21e and read-only memory (ROM) for storing programs for control procedures and basic data required for control
22e, a random access memory (RAM) 23e for temporarily storing a numerical value during calculation, an output interface (I / O) 24e, an amplifier 25 for outputting a swash plate drive signal to the swash plate control device 8, and a control It is composed of a digital input interface (D / I) 29e for inputting the operation state signal Lv from the unit 17.

FIG. 27 shows the structure of the control unit 17.
In the figure, the same parts as the control unit 18 are shown by the same numbers as in FIG. The operation signal X of the operation lever 4 is converted into a digital signal by the A / D converter 20f. The D / A converter 26f reconverts the digital signal into an analog signal,
These analog signals are amplified by the amplifiers 28L and 28R and output to the solenoid valves 3L and 3R. Further, an operation state signal Lv indicating the operation state of the operation lever 4 is output to the control units 18 and 19 via the digital output interface (D / O) 30.

FIG. 28 shows the structure of the control unit 19.
In the figure, the same parts as the control unit 18 are indicated by the same numbers as in FIG. Throttle lever 16 throttle signal N
L, governor lever angle detector 15 governor lever angle signal Ng
Is converted into a digital signal by the A / D converter 20g. The signal to the motor 14 is output to the interface (I
/ O) 24g and the motor driver 31 are output. In addition, like the control unit 18, the control unit 17
The operation state signal Lv from the input terminal is input via the digital input interface (D / I) 29g.

FIG. 29 shows the ROM 22e of the control unit 18.
4 shows a flowchart of the control procedure stored in FIG. First,
In step 100, the pressure signal Pd and the swash plate position signal θ are read via the A / D converter 20e. Next, in step 101, the operation state signal Lv from the control unit 17 is read in via the digital input interface (D / I) 29e.

Next, in step 102, the operation state signal Lv
The maximum value of the pump tilt angle θmax is set in accordance with. The details are shown in FIG. First, in step 102a, it is determined whether the operation state signal Lv is in the "ON" state. If the operation state signal Lv is'ON ', that is, if it is in the operated state, the procedure proceeds to step 102b to set the maximum value θmax1 of the actuator tilting to the maximum value θmax of the pump tilt angle.

In step 102a, the operation state signal Lv is "ON".
If not, that is, if it is determined that the pump is not operated, the procedure proceeds to step 102c, and the pump tilt angle maximum value θma
Set the standby flow rate θmax2, which is the maximum value when the actuator is not operated, to x.

Next, in step 110, the target tilt angle θr of the pump is calculated. The details are shown in FIG. First, in step 110a, the target tilt angle θr1 is calculated from the pressure signal Pd and the value of the hydraulic pump target absorption torque Tr. θr1 = C · Tr / Pd Next, in step 110b, the target tilt angle θr1 and the pump tilt angle maximum value θmax are compared. If θr1 ≧ θmax, step 1
In 10c, the final target tilt angle θr is θr = θmax. If θr1 <θmax, then θr = in step 110d
Let θr1.

Next, in step 120, a drive signal is output to the swash plate control device 8 so that the swash plate position signal θ matches the target tilt angle θr.

FIG. 32 shows the ROM 22f of the control unit 17.
4 shows a flowchart of the control procedure stored in FIG. First,
In step 200, the operation signal X is read via the A / D converter 20f. Next, in step 201, the operation signal X is determined and the operation state signal Lv is set. The details are shown in Fig. 3.
3 shows.

First, in step 201a, the absolute value of the operation signal X is compared with the dead zone value Xo. When | X | ≧ Xo, that is, when it is determined that the operation lever is operated, the procedure goes to step 201b to set the operation state signal Lv to “ON”.

When | X | <Xo, it is determined that the operation lever is not operated, and the procedure goes to step 201c to set the operation state signal Lv to "OFF". At this time, the value of Xo becomes a value peculiar to the model. Next, in step 202, the control unit 1 is operated via the digital output interface (D / O) 30.
The operation state signal Lv is output to 8 and 19. Next, step 21
At 0, the valve operation amounts Y1 and Y2 are calculated using the operation signal X, the calculation coefficient Ky, and the dead zone value Xo.

When X ≧ 0 Y1 = Ky · (X−Xo) Y2 = 0 When X <0 Y1 = 0 Y2 = Ky · (| X | −Xo) At this time, Ky and Xo are determined by this hydraulic circuit. It is a unique value depending on the model used. Next, in step 220, the valve operation amounts Y1 and Y2 are output via the D / A converter 26f and the amplifiers 28L and 28R.

FIG. 34 shows the ROM 22g of the control unit 19.
4 shows a flowchart of the control procedure stored in FIG. First,
In step 300, the throttle signal NL and the governor lever angle signal Ng are read via the A / D converter 20g. Next, in step 310, the digital input interface (D
/ I) Read the operation state signal Lv from the control unit 17 via 29g.

Next, in step 320, the operation state signal Lv
And the target governor lever angle Nr are set. Figure 3
5 shows details of the procedure 320.

First, in step 320a, the operation state signal L
Determine v. When it is determined in step 320a that Lv = 'OFF', that is, the operation lever 4 is not operated, the procedure proceeds to step 320c. In step 320c, throttle signal NL
And the standby rotation speed Nmin2 which is the minimum value when the actuator is not operated is set in advance. NL ≧ Nmin
In the case of 2, go to step 320d and set the target governor lever angle Nr.
Set Nmin2 to. When it is determined that NL <Nmin2 in step 320c, Nr = NL is set in step 320e.

If it is determined in step 320a that Lv = 'ON', that is, the operation lever 4 is operated, step 320
go to b. Similar to the case of Lv = 'OFF', the throttle signal NL is compared with Nmin1 which is virtually set at a position slightly higher than the maximum engine speed setting value. In this case, NL <Nmin1 is always satisfied. Because it is established, step 32
In 0b, Nr = NL.

The values of Nmin1 and Nmin2 are peculiar values depending on the specifications of the vehicle body in which this engine is used. Finally, in step 330, control is performed so that the target governor lever angle Nr and the governor lever angle signal Ng match.

[0024]

The control device having these configurations has the following problems. (1) For example, in the prior art example, only two signals are exchanged between the control units 17 and 18 and between the control units 17 and 19, but as the control becomes complicated, the signal line As the number increases, the wiring becomes complicated. Therefore, the probability of wiring failure increases, and it becomes difficult to find the failure.

(2) When the wiring from the control unit 17 to the other control unit 18 or 19 is broken, the control of the other control unit becomes inconsistent, causing an abnormality in the operation of the vehicle body.

(3) The control units 17, 18 and 19 are
Since the detection signal is input, the data is processed, and the device drive signal is output, as described above, the A / D converter 20
e, f, g, or output interface (I / O)
24e and 24g, expensive input / output devices such as amplifiers are required, and accordingly, a large-capacity power source and a large-area board are required, and the unit price of the control unit becomes expensive. Therefore, when changing the basic data to improve the performance, the expensive control unit 17, 18 or 19 itself must be replaced each time, which is uneconomical.

(4) The control units 17, 18 and 19 use θmax1, θmax2, which are used for calculation as shown in FIGS. 30 and 35, depending on the model in which this hydraulic circuit is used.
Nmin2 is different. Therefore, even though the control program is common, it is necessary to prepare various types of control units for each model, which complicates production management.

(5) Due to the reason (4) above, there are various types of control units for each model.
There is a possibility that the combination of 7, 18 and 19 may be wrong.

(6) Control unit 17 or 1 in case of failure
A similar error can occur when replacing 8 or 19.

A first object of the present invention is to provide an electronic control device for a hydraulic circuit, in which the number of signal lines between control units is reduced, there are few wiring failures, and repairs are easy even when a failure occurs. That is.

A second object of the present invention is to provide an electronic control device for a hydraulic circuit, which makes it possible to replace a control unit for improving performance at low cost.

A third object of the present invention is to avoid the complexity of having to produce several kinds of control units in an electronic control unit for a hydraulic circuit only due to the difference in basic data, and at the time of assembly or repair. An object of the present invention is to provide an electronic control device that does not cause a wrong combination of control units and is less likely to cause a mismatch in control states.

[0033]

In order to achieve the above first object, the present invention provides first and second hydraulic circuit control means.
In the electronic control device including the control unit, a third control unit is provided separately from the first and second control units, and the first control unit sends an operation state signal to the third control unit. The third control unit has a first communication unit for transmitting, and the third control unit stores a basic data used for control calculation in the second control unit and an operation state signal from the first control unit. Second communication means for receiving and transmitting the basic data to the second control unit based on the operation state signal,
The control unit includes a third communication unit that receives the basic data from the third control unit, and a unit that inputs the received basic data and uses it for control calculation.

Preferably, in the electronic control unit for the hydraulic circuit, a plurality of the second control units are provided.

In order to achieve the above first to third objects, the present invention provides an electronic control device comprising first and second control units for controlling a hydraulic circuit, wherein the first and second control units are provided. And a third control unit, the first control unit having first communication means for transmitting an operation state signal to the third control unit, and the third control unit. Means for storing the first basic data used for the control calculation in the first control unit and the second basic data used for the control calculation in the second control unit, and the first basic data for storing the first basic data Second communication for transmitting to the first control unit, receiving an operation state signal from the first control unit, and transmitting the second basic data to the second control unit based on the operation state signal With means The first communication means of the first control unit has a function of receiving the first basic data from the third control unit, and the first control unit inputs the received first basic data. The second control unit receives the second basic data from the third control unit, and the received second basic data. Means for inputting and using for control calculation.

Preferably, in the electronic control device for the hydraulic circuit, a plurality of the second control units are provided.

[0037]

In the present invention constructed as above, the second
Even if the number of control units increases or the control becomes complicated, the signals between the control units are exchanged via one communication line via the third control unit, so that the wiring is simplified and a failure occurs. The probability is reduced, and at the same time, it is easy to find when a failure occurs.

Further, in the present invention, the basic data corresponding to the model and control state is stored only in the third control unit, and the first and second control units do not need to store the basic data. It suffices to have a common one for all models. Therefore, the first and second control units can be mass-produced and can be manufactured at low cost.

Furthermore, since the third control unit does not include expensive input / output equipment and a power supply attached to it,
It can be manufactured at low cost. Therefore, the cost of the control unit as a whole can be reduced, and the control unit for the purpose of improving the performance can be exchanged only by the inexpensive third control unit, and the control unit can be exchanged at a low cost.

Basic data corresponding to the model and control state is stored only in the third control unit, and the first and second control units do not need to store basic data. Is enough. Therefore, the production management of the control unit is facilitated.

Further, the first and second control units are common to all models with respect to the third control unit storing the basic data, so that an error in combination can be prevented.

[0042]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 shows the overall configuration of the electronic control unit of this embodiment. This electronic control unit is connected between an engine 13, a hydraulic pump 1 driven by the engine 13, a hydraulic actuator 2 driven by pressure oil discharged from the hydraulic pump 1, and a hydraulic pump 1 and a hydraulic actuator 2. A control valve 3 for controlling the flow rate of pressure oil supplied to the hydraulic actuator 2;
It is composed of a control unit 10, a control unit 11 and a control unit 12.

The control unit 11 is a control unit for storing basic data, and performs data communication with other control units 7, 10 and 12.

The rotation speed of the engine 13 is controlled by the governor 13a. The setting of rotation speed at this time is governor 1
This is done by changing the angle of the governor lever 13b built in 3a. The governor lever 13b is provided with a governor lever angle detector 15 that detects the angle of the governor lever 13b. The signal monitored by the governor lever angle detector 15 and the signal from the throttle lever 16 are transmitted to the control unit 12, and the control unit 12 drives the motor 14 based on these signals to control the angle of the governor lever 13b to thereby control the engine. The rotation speed of 13 is controlled.

In the hydraulic pump 1, the signals from the pressure detector 5 and the swash plate position detector 6 are transmitted to the control unit 7, and the control unit 7 controls the position of the swash plate 1a through the swash plate position control device 8 by the signals. The displacement volume, that is, the discharge flow rate is controlled.

The opening of the control valve 3 is controlled by the solenoid valves 3L and 3R receiving a signal from the control unit 10 by the operating lever 4, and the opening degree thereof is controlled to control the direction and flow rate of the pressure oil to the actuator 2 or the tank 9. .

The structure of the control unit 7 is shown in FIG. The control unit 7 receives the pressure signal Pd from the pressure detector 5 and the swash plate position signal θ from the swash plate detector 6 and converts it into a digital signal, and a central processing unit (CPU).
21a and a read-only memory (ROM) 22a for storing a control procedure program and basic data necessary for control
, A random access memory (RAM) 23a for temporarily storing a numerical value during calculation, and an output interface (I
/ O) 24a, an amplifier 25 that outputs a swash plate drive signal to the swash plate control device 8, and a serial interface (SI) that performs data communication according to commands from the control unit 11 and the CPU.
/ O) 27a.

The structure of the control unit 10 is shown in FIG. In the figure, the same parts as the control unit 7 are shown by the same numbers as in FIG. The operation signal X of the operation lever 4 input to the A / D converter 20b is converted into a digital signal. D / A converter 2
6b reconverts the digital signal into an analog signal, and these analog signals are amplified by the amplifiers 28L and 28R and output to the solenoid valves 3L and 3R. The serial interface (SI / O) 27b is connected to another control unit 11 and CP.
Data communication is performed according to the U command.

The structure of the control unit 12 is shown in FIG. In the figure, the same parts as the control unit 7 are shown by the same numbers as in FIG. The throttle signal NL of the throttle lever 16 and the governor lever angle signal Ng of the governor lever angle detector 15 are A
It is converted into a digital signal by the / D converter 20c. The signal to the motor 14 is an output interface (I / O)
It is output via 24c and the motor driver 31. The serial interface (SI / O) 27c communicates data with another control unit 11 according to a command from the CPU.

The structure of the control unit 11 is shown in FIG. In the figure, the same parts as the control unit 7 are shown by the same numbers as in FIG. The serial interface (SI / O) 27d communicates data with other control units 7, 10 and 12 according to a command from the CPU.

Serial interface (SI / O) 2
FIG. 6 shows an example of a communication method using 7d. The figure shows communication from the control unit 11 to the control unit 7. Serial interface of control unit 11 (S
The I / O) 27d converts one parallel data sent from the CPU 21d into time series data bit by bit and serial interface (S) of the control unit 7 of the communication destination.
I / O) 27a. The serial interface (SI / O) 27a, which has received the serial data, converts the data received in time series bit by bit into parallel 1 data again. CPU 21 of control unit 7
a refers to the state of the serial interface (SI / O) 27a, and when parallel data is input, the data is read. By repeating the above operation, a plurality of data can be communicated. These serial interfaces (SI / O) can be easily obtained as commercial LSIs.

The control procedure stored in the ROMs 22a to 22d of each control unit will be described with reference to FIGS. The control procedure of the control unit 11 is shown in FIG. First, step 30
At 0, the basic data Tr is communicated to the control unit 7 via the SI / O 27c. Next, in step 310, basic data Ky and Xo are communicated to the control unit 10 also via the SI / O 27c. At this time, basic data Tr, Ky,
Xo is a set and corresponds to one specific model.

FIG. 8 shows details of the procedure 300 shown in FIG. First, in step 320, the SI of the control unit 11 is
/ O 27c is initialized, that is, the number of bits of one data in serial communication, communication speed, etc. are set. Then, the procedure proceeds to step 301.

In step 301, Tr data is communicated to the control unit 7 via the SI / O 27c. On this occasion,
As shown in FIG. 9A, a start code that is the beginning of the data, a destination address (in this case, the number of the control unit 7) for identifying that the control unit that received the data is the transmission to itself, Tr Data and an end code indicating the end of the data are transmitted as a set of data. That is, the CPU 21d, SI / O 27d and CP shown in FIG.
The communication procedure by the U21a and SI / O 27a is performed four times including the start code, the destination address, the Tr data, and the end code, and then transmitted.

Next, in step 302, it is determined whether a response from the control unit 7 has been received. When the control unit 7 receives data from the control unit 11 as described later, the control unit 7 returns a response to the data. As shown in FIG. 9B, the response data includes a start code, a sender address indicating which control unit the response is from,
It is a set of data of a response code and an end code. At this time, the communication procedure shown in FIG. 6 is reversed and performed four times to receive a set of data. If no data is received from the control unit 7, the procedure goes to step 303.

In step 303, it is determined whether a fixed time has elapsed in consideration of the response delay from the control unit 7. If it has not elapsed, the process returns to step 302 again to determine the response from the control unit 7. If it is determined that the time has passed, step 30
It returns to 1 and transmits data to the control unit 7 again. This is because the control unit 7 is not ready for communication, cannot receive data from the control unit 11, and cannot return a response.

On the other hand, in step 302, the control unit 7
If it is confirmed that the response is received, the procedure goes to step 310 to communicate the data Ky, Xo to the control unit 10. This procedure is similar to that shown in procedure 300. However, the data transmitted from the control unit 11 to the control unit 7 is as shown in FIG. 9 (c), and the destination address is the control unit 10, and since two data of Ky and Xo are transmitted, a total of 5 data are integrated. It becomes a set of data. The response data from the control unit 10 is shown in FIG. 9 except that the source address is the control unit 10 as shown in FIG.
It has the same configuration as (a).

Next, in step 400, the control unit 1
0 to the Lv signal request command via the serial interface (SI / O) 27b. This command is arranged such that when a specific code is communicated between both control units, it is recognized as an Lv transmission request, and that code is used. The structure of the communication data at that time is shown in FIG. At this time, as shown in FIG. 10A, a start code, which is the beginning of the data, and a destination address (in this case, the control unit 1) for identifying that the control unit receiving the data is the transmission to itself.
0 number), an Lv transmission request, and an end code indicating the end of data are transmitted as one set. That is, the CPU 21a and the serial interface (SI
/ O) 27a and serial interface (SI /
O) The communication procedure with the 27d and the CPU 27a is performed four times including a start code, a destination address, an Lv transmission request, and an end code, and then transmitted.

Next, the routine proceeds to step 410, where it is judged whether the operation state signal Lv is received from the control unit 10. When the control unit 10 receives the Lv transmission request from the control unit 11 as described later, the control state signal Lv
To return. This response data is shown in Fig. 10 (b).
As shown in (1), it is a set of data including a start code, a transmission source address indicating which control unit the response is from, Lv data, and an end code. At this time, FIG.
The communication procedure shown in is reversed and is performed four times to receive a set of data.

Next, in step 420, Lv received earlier
Determines whether has changed from the previous state. If it has not changed, the procedure returns to step 400. If it has changed, step 43
Move to 0. In step 430, the state of Lv is determined.

If Lv is'ON ', the procedure moves to step 440. In step 440, the maximum value θmax1 during the operation of the actuator is set to the pump tilt angle maximum value θmax, and the θmax data is transmitted to the control unit 7 via the serial interface (SI / O) 27a. Details of step 440 are shown in FIG.

First, in step 440a, the maximum value θmax1 of the pump tilt angle is set to the maximum value θmax1 during the operation of the actuator.
To set. This value of θmax1 is a unique value depending on the specifications of the vehicle body in which this pump is used. θmax1 will be described later.

Next, in step 440b, the θmax data is transmitted to the control unit 7. At this time, as shown in FIG. 10C, the start code, destination address, θmax data, and end code are transmitted as one set of data.

Next, in step 440c, it is determined whether a response from the control unit 7 has been received. As will be described later, when the control unit 7 receives the θmax data from the control unit 11, the control unit 7 returns the response shown in FIG. 10D so that it can be confirmed that the transmission / reception is surely performed. When the response is received, the procedure proceeds to step 450.

In step 450, similarly, the governor lever angle set value Nmin1 for operating the actuator is set to the governor lever angle set value Nmin, and Nmin is set to the control unit 12 via the serial interface (SI / O) 27c.
Send data. Details of procedure 450 are shown in FIG.

First, in step 450a, the governor lever angle set value Nmin1 is set to the governor lever angle set value Nmin1 when the actuator is operated. This value of Nmin1 is a unique value depending on the specifications of the vehicle body in which this engine is used.
Nmin1 will be described later.

Next, in step 450b, Nmin data is transmitted to the control unit 12. At this time, as shown in FIG. 10 (e), the start code, the destination address, the Nmin data, and the end code are transmitted as one set of data.

Next, in step 450c, it is determined whether a response from the control unit 12 has been received. As will be described later, when the control unit 12 receives the Nmin data from the control unit 11, the control unit 12 returns the response shown in FIG. 10 (f) so that it can be confirmed that the transmission / reception is surely performed. When the response is received, the process returns to step 400.

On the other hand, if it is determined in step 430 that Lv is'OFF ', the procedure proceeds to step 460. In step 460, the maximum value θmax2 of the pump tilt angle is set to the maximum value θmax2 when the actuator is not operated, and the maximum value θmax2 is transmitted to the control unit 7 in the same manner as in step 440. Here, θmax2 is a unique value depending on the specifications of the vehicle body in which this pump is used. θmax2 will also be described later.

Next, in step 470, the minimum value Nmin2 when the actuator is not operated is set for the governor lever angle set value Nmin, and the minimum value Nmin2 is transmitted to the control unit 12 in the same manner as in step 450. This Nmin2 becomes a unique value depending on the specifications of the vehicle body in which this engine is used. Nmin2 will also be described later. When step 470 ends, the process returns to step 400. As described above, in the control unit 11, the procedure 400-
470 is always repeated.

The control procedure of the control unit 7 is shown in FIG. The difference from the control procedure of the control unit 18 shown in FIG. 29 is that the procedures 101 and 102 are eliminated and the procedures 130A, 130 and 140 are added first.

In step 130A, the target absorption torque Tr of the hydraulic pump, which is basic data used for control calculation, is read from the control unit 11 via the serial interface (SI / O) 27a and stored in the RAM 23a. Figure 1
4 shows the details of this procedure 130A.

First, in step 131, the control unit 7
Initialize the serial interface (SI / O) 27a. Next, in step 132, the reception of the data shown in FIG. 9A from the control unit 11 is determined.
If not, go to step 132 until data is received.
repeat. If data is received, step 133
Move to.

In step 133, it is determined whether the destination address of the data shown in FIG. 9A is itself, that is, the control unit 7. If it is determined that the address is not its own address, the process returns to step 132 and waits again for communication from the control unit 11. If it is determined that the address is its own address, the process proceeds to step 134.

In step 134, the Tr data shown in FIG. 9A is stored in the RAM 23a. Next, the procedure proceeds to step 135, the response shown in FIG. 9B is transmitted to the control unit 11, and the procedure proceeds to the normal control procedure after step 130.

In a normal control procedure, first in step 130,
It is determined whether or not there is communication from the control unit 11 via the serial interface (SI / O) 27a.
If there is no communication, the process moves to step 100 and normal control is continued. If it is determined that there is communication in step 130, step 14
Move to 0.

In step 140, the pump displacement maximum angle θmax of the hydraulic pump, which is the basic data used for control calculation, is read from the control unit 11 via the serial interface (SI / O) 27a and stored in the RAM 23a. The details of this procedure 140 are shown in FIG.

In step 141, the destination address of the data shown in FIG. 10C is itself, that is, the control unit 7.
Is determined. If it is determined that the address is not the address itself, the process moves to step 100 and waits again for communication from the control unit 11. If it is determined that the address is itself, the procedure proceeds to step 142.

In step 142, θmax shown in FIG.
The data is stored in the RAM 23a. Next, the procedure moves to step 143, the response shown in FIG. 10D is transmitted to the control unit 11, and the procedure moves to step 100 to start normal control.

Next, in step 110, the target tilt angle θr is calculated using θmax stored in the RAM 23a. The details are shown in FIG.

First, in step 110a, the pressure signal Pd
And the target tilt angle θr from the value of the hydraulic pump target absorption torque Tr
Calculate 1 θr1 = C · Tr / Pd Next, in step 110b, the target tilt angle θr1 and the pump tilt angle maximum value θmax are compared. If θr1 ≧ θmax, step 1
In 10c, the final target tilt angle θr is θr = θmax. If θr1 <θmax, then θr = in step 110d
Let θr1.

Here, regarding the steps 110c and 110d, the above-mentioned θmax1 and θmax2 stored as θmax are stored.
This will be described with reference to FIG. In FIG. 17, θma
x1 is a soft upper limit value of the tilt angle which is set to a position slightly lower than the mechanical upper limit of the pump. θmax2 is
It is the standby flow rate set to the minimum flow rate required for lubrication when the actuator is not operated. Further, θr1 becomes a hyperbola as shown.

If Lv is'ON ', step 440 of FIG.
As a result, θmax1 is transmitted from the control unit 11 as θmax. In this case, in step 110, θr = θmax1 is set when θmax1 ≦ θr1, but θr = θr1 is set when θmax1> θr1 so that θr does not exceed θmax1.

When Lv is'OFF ', the procedure 46 in FIG. 7 is performed.
When 0, θmax2 is transmitted from the control unit 11 as θmax. In this case, since θmax2 is always smaller than θr1, θr = θmax2 is set in step 110c, and the hydraulic pump is kept at the standby flow rate. as mentioned above,
The values of θmax1 and θmax2 are unique values depending on the specifications of the vehicle body in which this pump is used.

Finally, in step 120, the target tilt angle θr
A drive signal is output to the swash plate control device 8 so that the swash plate position signal θ coincides with.

The control procedure of the control unit 10 is shown in FIG. The difference from the control procedure of the control unit 13 shown in FIG. 32 is that the procedure 202 is eliminated and the procedure 200A,
That is, 230 and 240 are added.

In step 200A, the operation coefficient Ky and the dead zone value Xo, which are the basic data used for the control operation, are read from the control unit 11 via the SI / O 27b, and the RAM 2 is read.
Store in 3b. This procedure is similar to that shown in FIG. 14, the received data is as shown in FIG. 9C, the stored data is Ky, Xo, and the response to the control unit 11 is as shown in FIG. The only difference is that of d).

Then, the procedure shifts to the normal procedure after the procedure 200, and the A / D converter 2 is operated in the procedure 200 as in FIG.
Operation signal X is read via 0b, and then step 201
At, the operation signal X is judged and the operation state signal Lv is set.

Next, in step 230, the control unit 1 is sent via the serial interface (SI / O) 27b.
It is judged from 1 whether there is a communication of the Lv transmission request.
If there is no communication, the process moves to step 210 and normal control is continued.

The details of this procedure 210 are shown in FIG. First, in step 210a, whether the operation signal X is positive or negative is determined. When X is positive (X ≧ 0), the procedure goes to step 210b to calculate the valve operation amounts Y1 and Y2. The calculation formula is as follows. Y1 = Ky.multidot. (X-Xo) Y2 = 0 Further, when it is determined in step 210a that X is negative (X <0), the routine proceeds to step 210c to calculate the valve operation amounts Y1 and Y2. The calculation formula is as follows. Y1 = 0 Y2 = Ky.multidot. (| X | -Xo) Here, FIG. 20 shows the relationship between the operation signal X and the valve operation amounts Y1 and Y2 calculated in the steps 210b and 210c. X in the figure
In the region of ≧ 0, Y1 has a value and Y2 is 0.
At this time, depending on the value of Xo, Y1 moves in parallel as shown by the chain line. Also, the slope changes as indicated by the chain double-dashed line depending on the value of Ky. In addition, Y1 is 0 in the region of X <0.
And Y2 has a value. The change of Y2 due to Xo and Ky is the same as the change of Y1. Step 210b or 210
When c is finished, the procedure moves to the next step 220.

On the other hand, if it is determined in step 230 that there is communication, the process proceeds to step 240. In step 240, Lv data is transmitted to the control unit 11 via the serial interface (SI / O) 27b. The transmission data at this time is as shown in FIG.

The control procedure of the control unit 12 is shown in FIG. Here, the difference from the control procedure of the control unit 19 shown in FIG. 34 is that the procedure 310 is eliminated, the procedures 340 and 350 similar to those of the control unit 7 are performed, and the procedure 360 is provided instead of the procedure 320. That is.

First, in step 340, the control unit 11 switches to N via the serial interface (SI / O) 27c.
Determine if there was min communication. If there is no communication, the process proceeds to step 300 and normal control is continued.

If it is determined in step 340 that there is communication, the process proceeds to step 350. In step 350, the governor lever angle set value Nmin, which is basic data used for control calculation, is read via the serial interface (SI / O) 27c and stored in the RAM 23c.

In step 360, the target governor lever angle Nr is set. The details are shown in FIG. First, step 360
At a, the throttle lever signal NL and the control unit 1
The governor lever angle set value Nmin received from 1 is compared. If NL ≧ Nmin, move to step 360 and set Nr to Nmin
Set the value of. When NL <Nmin, the process proceeds to step 360c, and the value of NL is set in Nr.

Now, regarding the procedure 360, the above-mentioned Nmin1 and Nmin2 stored as Nmin will be described with reference to FIG. In FIG. 23, Nmin1 is a virtual value set at a position slightly higher than the set value of the maximum engine speed. Nmin2 is a standby speed set to a low value to save energy, and set to a value slightly higher than the idle position so that there is no delay in the rise of the engine speed when Lv becomes'ON '. To be done.

As described above, when Lv is ON ', as shown in FIG.
According to the procedure 450, Nmin1 is transmitted from the control unit 11 as Nmin. In this case, the throttle lever 16
Since the set value NL according to (1) is always smaller than Nmin1, NL is always set as Nr in step 360c.

On the other hand, when Lv is'OFF ', Nmin2 is set as Nmin from the control unit 11 by the procedure 470 of FIG.
Will be sent. At this time, if the set value NL set by the throttle lever 16 is in a region (B) larger than Nmin2, that is, if NL ≧ Nmin2, Nr is set to Nmi in step 360b.
n2 is set and the engine is kept at standby speed. On the other hand, the set value NL set by the throttle lever 16 is Nm.
In the area (A) smaller than in2, that is, when NL <Nmin2, NL is set to Nr in step 360c.

FIG. 24 shows a schematic diagram of signal transmission / reception between the control units 7, 10 and 12 centering on the control unit 11 described above. As described above, the basic data Tr is communicated to the control unit 7 in the procedure 300 of FIG. 7, and the basic data Ky, Xo is communicated to the control unit 10 in the procedure 310. Then, in step 410, it is determined whether the operation state signal Lv is received from the control unit 10.

When it is judged that the operation state signal Lv is received,
In step 440, the maximum value θmax1 of the pump tilt angle during operation is set to the maximum value θmax1 or in step 460 the maximum value θmax2 when the actuator is not operated is set to θmax, and the θmax data is transmitted to the control unit 7. Then, in step 450, the governor lever angle set value Nmin1 is set to the governor lever angle set value Nmin, or in step 470, the standby rotation speed N is set.
Set min2 and send to the control unit 12.

In the present embodiment, the control unit 11 sends the pump tilt angle maximum value θmax to the control unit 7 and the governor lever angle set value Nmin to the control unit 12 according to the operation state signal Lv of the control unit 10. In contrast to this, a configuration in which the control unit 7 or 12 issues an operation state signal Lv and the control unit 11 transmits data to another control unit in response to this is also conceivable.

In the above, the control units 7, 10, 1
No. 2 does not require different data for each model, so that data common to all models can be used. Therefore, the control units 7, 10, 12 can be mass-produced,
It can be manufactured at low cost. In addition, the control unit 11
Can be manufactured at low cost because it does not have expensive input / output devices and devices attached thereto.

Therefore, according to the present embodiment, since the signals between the control units 10, 7 and 12 are exchanged via the control unit 11 by one communication line, the wiring is simple and there are few malfunctions. Even if it occurs, it will be easy to find.

In addition, the control units 7, 10, 11, 12
The overall cost can be reduced. Further, when replacing the control unit to improve performance, only the inexpensive control unit 11 needs to be replaced, and the control units 7, 10 and 12 having an expensive input / output mechanism need not be replaced. Can be replaced at low cost.

Further, only the control unit 11 stores the basic data corresponding to the model and control state, and the control units 7, 10 and 12 do not need to store the basic data, and it is sufficient to prepare common data for all models. Therefore, the complexity of producing many types of these two control units for each model can be avoided, and the production management of the control units can be facilitated.

Further, in the production / assembly of a certain model,
Control unit 11 storing basic data specific to the model
On the other hand, since the control units 7, 10 and 12 are common to all models, it is possible to prevent an error that the control unit 7, 10, 12 of another model is combined with this specific model.

In the above embodiments, the function of SI / O in the communication procedure of this basic data does not restrict the present invention, and an LSI used for LAN or the like, a method of communicating by parallel signals, etc. are used. Other means are also acceptable. The configuration of the communication data is not limited to that shown in this embodiment, and the start code and end code may be omitted as a fixed data length, or all the data may be converted into character codes for communication. Any configuration may be used as long as it matches. Further, in the present embodiment, the control unit of the hydraulic pump, the engine and the control valve has been shown, but the present invention can be applied to other control units conceivable as a construction machine, for example, for controlling the operation of the monitor display front member.

[0108]

According to the present invention, the number of signal lines can be reduced to reduce the number of wiring failures, and even when a failure occurs, it is easy to repair it.

Further, according to the present invention, the first and second control units can be mass-produced, and the third control unit does not require an input / output device, so that the cost of the entire control unit can be reduced. . Further, the control unit can be replaced at low cost for improving the performance. Also, the first
Since the second control unit and the second control unit are common to all models, production management of the control unit is facilitated. In addition, an error in the combination of control units is less likely to occur during assembly or repair, and reliability can be improved.

[0110]

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of an electronic control device that is an embodiment of the present invention.

FIG. 2 is a configuration diagram of a control unit.

FIG. 3 is a configuration diagram of a control unit.

FIG. 4 is a configuration diagram of a control unit.

FIG. 5 is a configuration diagram of a control unit.

FIG. 6 is a diagram showing an example of a communication method using a serial interface.

FIG. 7 is a flowchart showing a control procedure stored in a ROM of a control unit.

FIG. 8 is a flowchart showing details of a control procedure.

FIG. 9 is a diagram showing a structure of communication data in a communication method.

FIG. 10 is a diagram showing a structure of communication data in a communication method.

FIG. 11 is a flowchart showing details of a control procedure.

FIG. 12 is a flowchart showing details of a control procedure.

FIG. 13 is a flowchart showing a control procedure stored in a ROM of a control unit.

FIG. 14 is a flowchart showing details of a control procedure.

FIG. 15 is a flowchart showing details of a control procedure.

FIG. 16 is a flowchart showing details of a control procedure.

FIG. 17 is a diagram showing details of setting a pump target tilt angle maximum value.

FIG. 18 is a flowchart showing the control procedure stored in the ROM of the control unit.

FIG. 19 is a flowchart showing details of a control procedure.

FIG. 20 is a diagram showing a relationship between an operation signal and a valve operation amount.

FIG. 21 is a flowchart showing the control procedure stored in the ROM of the control unit.

FIG. 22 is a flowchart showing details of a control procedure.

FIG. 23 is a diagram showing details of setting a target governor lever angle.

FIG. 24 is a schematic diagram of transmission / reception of basic data.

FIG. 25 is an overall configuration diagram of a conventional electronic control device for a hydraulic circuit.

FIG. 26 is a configuration diagram of a control unit.

FIG. 27 is a configuration diagram of a control unit.

FIG. 28 is a configuration diagram of a control unit.

FIG. 29 is a flowchart showing the control procedure stored in the ROM of the control unit.

FIG. 30 is a flowchart showing details of a control procedure.

FIG. 31 is a flowchart showing details of a control procedure.

FIG. 32 is a flowchart showing the control procedure stored in the ROM of the control unit.

FIG. 33 is a flowchart showing details of a control procedure.

FIG. 34 is a flowchart showing the control procedure stored in the ROM of the control unit.

FIG. 35 is a flowchart showing details of a control procedure.

[Explanation of symbols]

 7 control unit 10 control unit 11 control unit 12 control unit 21a-d central processing unit (CPU) 22a-d read only memory (ROM) 23a-d random access memory (RAM) 27a-d serial interface (SI / O)

Claims (4)

[Claims] 1. An electronic control device comprising first and second control units for controlling a hydraulic circuit, wherein a third control unit is provided separately from the first and second control units, and the first control unit is provided. The control unit has first communication means for transmitting an operation state signal to the third control unit, and the third control unit stores basic data used for control calculation in the second control unit. Means and
A second communication unit for receiving an operation state signal from the first control unit and transmitting the basic data to the second control unit based on the operation state signal, the second control unit Is an electronic control device for a hydraulic circuit, comprising: third communication means for receiving the basic data from the third control unit; and means for inputting the received basic data and using it for control calculation. 2. The electronic control device for a hydraulic circuit according to claim 1, wherein a plurality of the second control units are provided. 3. An electronic control device comprising first and second control units for controlling a hydraulic circuit, wherein a third control unit is provided separately from the first and second control units, and the first control unit is provided. The control unit has first communication means for transmitting an operation state signal to the third control unit, and the third control unit has first basic data used for control calculation in the first control unit. And means for storing second basic data used for control calculation in the second control unit, and transmission of the first basic data to the first control unit and operation from the first control unit. Second communication means for receiving a status signal and transmitting the second basic data to the second control unit based on the operation status signal, the first communication means of the first control unit. Is the third The first from the control unit 1
Of the basic data, and the first control unit has means for inputting the received first basic data for use in control calculation, and the second control unit is provided with the third control unit. An electronic control device for a hydraulic circuit, comprising: a third communication means for receiving the second basic data from the control unit, and means for inputting the received second basic data and using it for control calculation. 4. The electronic control device for a hydraulic circuit according to claim 3, wherein a plurality of the second control units are provided.