JPH08255009A - Electronic control unit for construction machine - Google Patents

Abstract

PURPOSE: To constitute a electronic control unit for a construction machine so that a control program and control parameters in a control box can easily be varied by an operator and are prevented from being rewritten by misoperation with simple and inexpensive constitution while the reliability of the product is guaranteed. CONSTITUTION: This unit is an electronic control unit which electrically control the hydraulic system of the construction machine and has a 1st unrewritable memory 32 which stores a rewriting procedure for rewriting control contents and a control procedure and a 2nd unrewritable nonvolatile memory 33 which has an area for storing the control procedure. Further, this unit consists of a 3rd rewritable memory 14, a control box 14 including a CPU 31 which performs system control by reading storage contents out of the 1st memory 32, 2nd memory 33, and 3rd memory 14, and a setter 41 which writes the control procedure in the 2nd memory according to the rewriting procedure stored in the 1st memory.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic control unit for an electronically controlled construction machine which can easily change a control program at a work site.

[0002]

2. Description of the Related Art In construction machines such as hydraulic excavators, in recent years, the hydraulic system has been electronically controlled for the purpose of facilitating its operation and improving its operability. Hereinafter, a hydraulic excavator will be described as a typical example. In the electronically controlled hydraulic excavator, a computer is mounted as an electronic control device, and a control program and standard control parameters for a standard work procedure regarding a work to be performed are stored in the memory thereof. The electronic control unit generates a control command using a control program and control parameters, and controls the operation of a valve or the like provided in the hydraulic system of the hydraulic excavator.

FIG. 3 shows an example of the internal structure of a conventional electronic control unit. In FIG. 3, reference numeral 11 is a control box containing an electronic control unit. The electronic control unit built in the control box 11 has a memory (EPROM) 12 for storing control content, control procedure (control program) and control parameters,
It is composed of a CPU 13 which reads out a control program and control parameters from the memory 12 to generate a control command, a memory (RAM) 14 which temporarily stores a calculation result, and a timer (TIM) 15 which manages a time cycle of control. . The storage contents of the memory 12 cannot be freely rewritten at the work site or the like. The electronic control unit sends a detection signal from a sensor 18 arranged in each part of the hydraulic excavator and an operation signal from various switches 19 operated by an operator through the input / output port 16 and the signal cable 17. A signal relating to the input and generated control command is output to the valve 20 of each part. The electronic control unit also includes an A / D converter 21 for converting an analog detection signal into a digital signal, a receiving circuit (DIO) 22 for receiving an operation signal from the switch 19, and a driver 23 for generating a drive signal based on a control command signal. Prepare

[0004]

With the recent electronic control devices for hydraulic excavators, there are cases in which the control contents and control programs of construction machines must be changed at the work site. That is, recently, the variety of construction work is progressing, and it is not possible to sufficiently meet all of the required work contents simply by exchanging attachments and accompanying control parameters. In this case, if the main body of the electronic control unit, that is, the hardware part is made common, and the control procedure (control program) regarding the control content, that is, the software is changed to an appropriate one, a sufficient correspondence can be achieved.

However, according to the configuration of the conventional electronic control device shown in FIG. 3, the control content and the control program are stored in the non-rewritable memory 12, and after the memory 12 is attached to the control box 11, the memory is not stored. The stored contents of 12 cannot be freely changed. Therefore, the conventional electronic control device is originally manufactured corresponding to each work, and the electronic control device having different control programs is treated as a different item. Since the electronic control devices having different control programs are treated as different objects, the management of the correspondence between the control programs of the electronic control devices and the work machine becomes complicated, which causes a price increase and troubles during work.

When considering rewriting / changing the control program at the work site, it is also desirable to rewrite / change the control parameter associated with the change of the control program.

An object of the present invention is to solve the above problems, and an operator can easily change a control program or a control parameter in a control box at a site for assembling an electronically controlled construction machine or a site for use. It is possible to secure the reliability of the product, and the circuit configuration is simple and inexpensive.
An object of the present invention is to provide an electronic control device for a construction machine capable of preventing rewriting due to a malfunction.

[0008]

An electronic control unit for a construction machine according to the present invention is an electronic control unit for electrically controlling a hydraulic system of a construction machine, and has a rewriting procedure for rewriting control contents and control procedure. A non-rewritable first memory for storing, a rewritable non-volatile second memory having an area for storing a control procedure, a readable / writable third memory, a first memory, a second memory, and A control device main body (control box) including a control execution unit (CPU) that reads out the contents stored in the third memory to control the system, and a setting for writing the control procedure in the second memory according to the rewriting procedure stored in the first memory. It is composed of

In the above structure, the setting device is detachable from the control device main body and can be used by being connected to the control device main body only when it is necessary to set the control procedure for each working machine. preferable.

In the above structure, the setting device has the connection identifying means, and the control device body stores the identification determining means for receiving the signal from the connection identifying means and the first memory in the first memory based on the determination operation of the identification determining means. And means for activating the stored rewriting procedure.

In the above structure, it is possible to provide the second memory with means for preventing data rewriting of the second memory when the setting device is not connected to the control device body.

In the above structure, the second memory has an area for storing the control parameter, and is provided with another setting device for rewriting the control parameter stored in the second memory and setting the control parameter for each working machine. Can be configured to.

In the above structure, the setting device and the other setting device are respectively detachable from the control device main body, and control is performed only when it is necessary to set a control procedure or control parameters for each working machine. It is preferably connected to the device body and used.

In the above structure, the setter and the other setters each have a connection identifying means, and the main body of the control device is
It may be configured to include an identification determination unit that receives a signal from the connection identification unit, and a unit that rewrites a control procedure or a control parameter in the second memory based on the determination operation of the identification determination unit.

[0015]

According to the present invention, the first memory for storing the rewriting procedure of the control program provided in the electronic control unit of the construction machine such as the hydraulic excavator and the second memory having the area in which the control program can be freely rewritten, The setting program that allows the control program in the second memory to be rewritten allows the control program for each work machine to be freely rewritten / changed at the work machine manufacturing site or work site. The setting device for rewriting the control program is
It is removable with respect to the control box, which includes the electronic control unit, which allows it to be performed by a specific operator.

In addition to rewriting / changing the control program by the setter, the control parameter can be rewritten by another setter which enables rewriting / changing of the control parameter stored in the second memory.

As described above, one or both of the control program and the control parameter of the control box in which the electronic control unit is incorporated can be easily changed at the assembly site and the work site according to the working machine.

Further, the erroneous input preventing means prevents erroneous deletion and rewriting of the control program and control parameters.

[0019]

Embodiments of the present invention will be described below with reference to the accompanying drawings. 1 is a block diagram showing an embodiment of an electronic control unit according to the present invention, and FIG. 2 is a flow chart showing the main operation.

In FIG. 1, elements that are substantially the same as the constituent elements of the conventional electronic control device described with reference to FIG. 3 are designated by the same reference numerals. Reference numeral 11 denotes a control box in which an electronic control unit is built in, and the control box 11 is attached to a working machine such as a hydraulic excavator (not shown). The work machine includes sensors such as a pressure sensor (or a differential pressure sensor) arranged in each part of a hydraulic drive system for operating the work machine, a position sensor (or a displacement sensor etc.) arranged in each drive part, or the like. 18 and various switches 19 arranged in the driver's seat and operated by the driver,
A valve 20 such as an electromagnetic proportional valve that is arranged in each part of the hydraulic drive system and adjusts the flow rate and the flowing direction of the hydraulic oil is provided. The control box 11 inputs a detection signal from the sensor 18 and an operation signal from the switch 19 via the signal cable 17, and outputs a control signal to each valve 20.

The electronic control unit built in the control box 11 reads a control program, control parameters, etc., and starts and executes the control program to generate a control command, a CPU 31, a control content and a control procedure, that is, a control program. The non-rewritable first memory (EPROM) 32 for storing the rewriting procedure for rewriting above, the control content, the control program, the control parameters, etc. are stored, and the control content, the control program, and the control parameter of each working machine are rewritten. The second memory (EEPROM) 33, which has a structure (non-volatile) in which the stored data does not disappear even when the power is turned off, and the second memory which is readable and writable Memory (RAM) 14 of 3 and a receiving circuit that receives data sent serially from an external setting device
(SIO) 34, a receiving circuit (DIO) 22 that receives an operation signal from an external switch 19, and a detection signal (analog signal) sent from the sensor 18 that is converted into a digital signal that can be processed by the CPU 31 A / It includes a D converter 21, a timer (TIM) 15 for managing a time cycle of control, and a driver 23 for generating a drive signal for driving a valve 20 for converting an electric signal into a hydraulic control amount. Again 16
Is the signal cable 17 or the connector 3 on the control box side.
5 is an input / output port to which it is connected.

The memory 33 has an area for storing control contents, an area for storing control programs, and an area for storing control parameters.

The setting device 41 is a setting device used by a worker in an assembly line in the manufacturing process of the working machine. The setting device 41 is provided with a switch 42 for various operations such as selection of control contents, a display portion 43, an EPROM insertion portion 44, a floppy insertion portion 45, and a communication port 46. The setting device 41 can be detachably connected to the connector 35 of the control box 11 using the connector 47.
The connector 47 has a switch 4 for notifying the CPU 31 that the setting device 41 is connected to the connector 35.
8 are provided. A connection pin or a connection cable can be used instead of the switch 48.

By operating the setting device 41 connected to the control box 11 by an assembling worker, the following can be set. Firstly, of the plurality of control contents stored in the setting device 41, the control contents corresponding to the type of working machine are selected by using the switch 42 provided on the panel of the setting device 41, and selected. Control content,
It is set in the memory 33 of the control box 11 using the rewriting procedure of the memory 32. Secondly, the EPROM 49 storing the desired control program is replaced with the EPROM inserting section 44.
, Or the floppy 50 in which the desired control program is stored, in the floppy insertion section 45.
By setting to, the control program can be read from the EPROM 49 or the floppy 50 and written in the memory 33 by using the rewriting procedure in the memory 32 based on a required operation. Third, the communication port 46
It is possible to create a control program and directly write the control program in the memory 33 of the control box 11 by connecting the software development device 51 via the.

The setting device 61 is another setting device, and the setting device 61 is used by a worker of a maker at a service factory where a front attachment according to a user's request is attached to a working machine or a user's work site. It The setting device 61 is a setting device for setting the data of the control parameter of each working machine required for control in the rewritable memory 33 in the control box 11. The setting device 61 is detachably attached to the control box 11, and normally,
When it is not connected to the control box 11 and it becomes necessary to change / set the control parameters, the connector 3 on the control box 11 side is connected via the dedicated connector 62.
Connected to 5. When newly setting the control parameters, the worker connects the setter 61 to the connector 35 and operates the setter 61 to set the control parameters. A switch 63 is provided on the connector 62 of the setting device 61.
The switch 63 is a switch for notifying the CPU 31 that the setting device 61 is connected to the connector 35 when the setting device 61 is connected to the control box 11. Instead of the switch 63, a connection pin or a connection cable can be used.

In the configuration in which the two setters 41 and 61 can be connected and the data set by each setter can be input to the control box 11, the single receiving circuit 34 is provided in view of simplification of the electric circuit ( Two are not provided individually), and they are shared for each setter. Further, in order to rewrite the contents of the memory 33 and to prevent each rewriting area from being changed by an erroneous operation, it is desirable that only one setter can be connected to the control box 11 at a time. Also memory 3
A multiplexer (MPX) 71 for 3 is provided. This multiplexer 71 is for distinguishing each writing area in the memory 33 and rewriting only to a designated rewritable area when either the setting device 41 or the setting device 61 is connected. . In the rewriting operation, an address signal or a control signal that is directly connected to the memory 33 from the CPU 31 is once input to the multiplexer 71, and a signal line that is connected from the CPU 31 to the memory 33 is connected depending on the connection state of the setter 41 and the setter 61. Switch with hardware. Further, the reading from the CPU 31 can be performed over the entire area of the memory 33.
Since the memory 33 is electrically rewritable, the multiplexer 71 also has a role of preventing data stored in the memory 33 from being rewritten and destroyed due to malfunction of the CPU 31 due to noise.

The main operation executed by the CPU 31 will be described with reference to FIG. This operation is an operation in which the CPU 31 in the control box 11 writes the control program of the working machine from the setting device 41 to the memory 33 in accordance with the rewriting procedure stored in the memory 32.

First, it is checked whether or not the signal from the switch 48 is input (step S1). When the signal is not input, it is checked whether or not the control program related to the working machine is stored in the memory 33 (step S
2). When there is no control program, the process returns to step S1 and stands by until the input signal from the switch 48 is input. If the control program for the working machine is already stored, this is executed (step S3). When the input signal from the switch 48 is detected in step S1, the data regarding the control program from the setter 41 is received and written in the designated area in the memory 33 (step S4). Next, the control program data written in the memory 33 is read out and sent back to the setter 41. C
The operation by the PU 31 is completed as described above.

In the setter 41, the control program data sent from the CPU 31 is compared with the send data,
It is determined whether or not a write error has occurred in the memory 33. If it is determined that an error has occurred, the data is sent again.

When rewriting and setting the control parameters by using the setter 61, the input of the signal from the switch 63 is waited for, and the setting is made when the input is made, as in the case of writing the control program. The control parameter data supplied from the container 61 is written in a designated area in the memory 33.

Since the control box 11 including the electronic control unit of the construction machine is configured as described above, even in a work site or an assembly site where the environment is poor, the control box 11 can be used as a work machine without opening and closing the control box. An appropriate control program according to the setting can be set using the setter 41. Further, if necessary, the setter 61 can be used to easily change and set the control parameters according to the work. In the control program rewrite setting and control parameter rewrite setting,
A preventive measure is provided in the memory 33 to prevent erasure or erroneous input.

The second memory 33 may have the following configuration. In addition to the above-mentioned control program storage area, control parameter storage area, etc., the CPU 3
It is possible to provide a failure diagnosis area in which 1 can always read and write freely. This failure diagnosis area is an area for recording an abnormal signal of the sensor 18 or the switch 19 generated during work by the working machine, and when an abnormality occurs in the working machine, the engine is turned off and the electronic control unit is powered off. This area is used when you want to know the cause of the abnormality even after the error has occurred.

The rewritable memory 33 can be divided into a plurality of storage areas in terms of hardware, and a necessary storage object can be allocated to each area to allow one memory to perform various purposes. This makes it possible to reduce the size and cost of the electronic control device.

[0034]

As is apparent from the above description, according to the present invention, in an electronic control unit for electrically controlling a hydraulic drive system of a construction machine such as a hydraulic excavator, internal data is rewritten from the outside in a control box. In particular, the control program can be written or changed at a work site such as an assembly line according to the type of work machine. Since the control program according to the work machine can be written or changed after the electronic control device is manufactured, the hardware can be standardized and the manufacturing cost can be reduced as a whole.

Further, by preparing another setting device, it is possible to rewrite / change the control parameters together with the rewriting / change of the control program, and the control parameters according to the working machine can be easily changed at the work site.

Further, by providing the connection identifying means in the connector of each setting device for setting the control program and the control parameters, the electric circuit in the control box can be simplified. Further, by providing the connection identification means and the erroneous input prevention means in the data transmission path of the rewritable memory,
It is possible to prevent the control program and the control parameters from being erased by hardware or from being erroneously input.

Further, by dividing the writing area of the electrically rewritable memory for each storage object, one memory can be effectively used without causing interference between stored data. As a result, manufacturing cost can be reduced and miniaturization can be achieved.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of an electronic control device for a construction machine according to the present invention.

FIG. 2 is a flowchart for explaining a main operation of the electronic control unit.

FIG. 3 is a configuration diagram of a conventional electronic control device for a construction machine.

[Explanation of symbols]

 11 Control Box 16 Input / Output Port 31 CPU 32 First Memory (EPROM) 33 Memory (EEPROM) 34 Receiver Circuit 41, 46 Setter 49 EPROM 50 Floppy 51 Software Development Device

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location G06F 9/06 540 G06F 12/14 310F 4 12/14 310 G05B 19/05 A

Claims (7)

[Claims] 1. An electronic control unit for electrically controlling a hydraulic system of a construction machine, wherein a non-rewritable first memory for storing a control content and a rewrite procedure for rewriting the control procedure, and an area for storing the control procedure. A rewritable non-volatile second memory, a readable / writable third memory, and contents stored in the first memory, the second memory, and the third memory, and system control is performed. An electronic control device for a construction machine, comprising: a control device main body including a control executing means; and a setting device that writes a control procedure in the second memory according to the rewriting procedure stored in the first memory. 2. The setting device is attachable to and detachable from the control device main body, and is connected to the control device main body and used only when setting of a control procedure for each working machine is required. The electronic control device for a construction machine according to claim 1, which is characterized in that. 3. The setting device has a connection identifying means, and the control device main body stores the identification determining means for receiving a signal from the connection identifying means, and the first memory in the first memory based on the determination operation of the identification determining means. An electronic control unit for a construction machine according to claim 1 or 2, further comprising means for activating the stored rewriting procedure. 4. The means for preventing rewriting of data in the second memory when the setting device is not connected to the control device body, is provided for the second memory. Electronic control unit for the described construction machine. 5. The second memory is provided with an area for storing a control parameter, and the control parameter stored in the second memory is rewritten, and another setting device for setting a control parameter for each working machine is provided. The electronic control device for a construction machine according to claim 1, which is characterized in that. 6. The setting device and the other setting device are respectively detachable from the control device main body, and the control is performed only when a control procedure or control parameter setting for each working machine is required. The electronic control device for a construction machine according to claim 5, wherein the electronic control device is used by being connected to the device body. 7. The setting device and the other setting device each have a connection identifying means, and the control device main body has an identification determining means for receiving a signal from the connection identifying means and a determining operation of the identification determining means. 7. The electronic control device for a construction machine according to claim 5, further comprising means for rewriting a control procedure or a control parameter in the second memory based on the above.