JP2000274262A - Electron governor for engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To appropriately correct errors of the control, due to the fluctuation of a resistance value of an electromagnetic coil by providing a resistor for detecting the fluctuation of a resistance value of the electromagnetic coil of an electromagnetic actuator, and correcting current-carrying capacity to the electromagnetic coil with a correction value obtained, on the basis of a voltage value applied to the resistor and a power source voltage value. SOLUTION: An electronic governor for engine has an electromagnetic actuator 1 having an electromagnetic coil 4, and current is made to flow into the electromagnetic coil 4 from a power source 5 of a drive circuit 2, and a control means for controlling the current-carrying capacity P is provided, and adjustment position of a fuel adjusting unit 6 is controlled by the operation of the electromagnetic actuator 1. In this case, since a resistor 7 is interposed in a current-carrying circuit 2 and a voltage value E1 to be applied to the resistor 7 is made to fluctuate with the fluctuation of a resistance value R2 of the electromagnetic coil 4, a correcting means 8 obtains a correction value C on the basis of the voltage value E1 and the voltage value E2 of the power source 5. The control means 3 corrects the current-carrying capacity P to the electromagnetic coil 4, on the basis of the correction value C obtained by the correcting means 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic governor for an engine and, more particularly, to an electronic governor capable of appropriately correcting a control error caused by a change in a resistance value of an electromagnetic coil of an electromagnetic actuator.

[0002]

2. Description of the Related Art Conventionally, an electronic governor of an engine is configured as follows. That is, an electromagnetic actuator, a drive circuit, and control means are provided, the electromagnetic actuator is provided with an electromagnetic coil, the drive circuit is provided with a power supply, and the power supply supplies power to the electromagnetic coil. The amount of electricity to the electromagnetic coil is controlled, and based on the amount of electricity to this electromagnetic coil, the electromagnetic actuator
The fuel metering unit is configured to control a metering position.

In this electronic governor, the temperature of the electromagnetic coil changes based on the change in the ambient temperature of the electromagnetic coil of the electromagnetic actuator and the change in the amount of heat generated by the electromagnetic coil itself, and the resistance value of the electromagnetic coil changes. In this case, the amount of current supplied to the electromagnetic coil fluctuates, and an error occurs in the control of the adjustment position of the fuel adjustment unit by the electromagnetic actuator.

Conventionally, as a technique for correcting such a control error, there is a technique for correcting a control amount based on a change in temperature of lubricating oil in a fuel injection pump.

[0005]

The above prior art has the following problems. The change in the temperature of the lubricating oil in the fuel injection pump has a low correlation with the change in the ambient temperature of the electromagnetic coil of the electromagnetic actuator, and does not reflect the change in the heating value of the electromagnetic coil itself. For this reason, it is not possible to properly correct a control error due to a change in the temperature of the electromagnetic coil of the electromagnetic actuator and a change in the resistance value of the electromagnetic coil.

An object of the present invention is to provide an electronic governor for an engine that can appropriately correct a control error caused by a change in the resistance value of an electromagnetic coil of an electromagnetic actuator.

[0007]

The structure of the first aspect of the present invention is as follows (see FIGS. 1 and 2). The electromagnetic actuator 1 includes a driving circuit 2 and a control unit 3. The electromagnetic actuator 1 includes an electromagnetic coil 4.
Is provided with a power supply 5, and supplies power to the electromagnetic coil 4 from the power supply 5. The control means 3 controls a power supply amount P from the power supply 5 to the electromagnetic coil 4, and controls a power supply amount to the electromagnetic coil 4. An electronic governor for an engine, in which the electromagnetic actuator 1 is configured to control a metering position of the fuel metering unit 6 based on P, includes a resistor 7 and a correction unit 8,
The resistor 7 is provided in the drive circuit 2 so that the voltage value E1 applied to the resistor 7 fluctuates based on the change in the resistance value R2 of the electromagnetic coil 4. A correction value C is obtained based on the voltage value E1 and the voltage value E2 of the power supply 5, and based on the correction value C, the control unit 3 controls the power supply amount P to the electromagnetic coil 4. Is corrected.

[0008]

Operation and Effect of the Invention (Invention of claim 1) The invention of claim 1 has the following operation and effects (see FIGS. 1 and 2). When the temperature of the electromagnetic coil 4 changes based on a change in the ambient temperature of the electromagnetic coil 4 or a change in the amount of heat generated by the electromagnetic coil 4 itself, and the resistance value R2 of the electromagnetic coil 4 changes, the resistance is determined based on the change. The voltage value E1 applied to 7 fluctuates. And
A correction value C is obtained based on the voltage value E1 applied to the resistor 7, and the amount of power P to the electromagnetic coil 4 is corrected based on the correction value C. As described above, since the amount of current P to the electromagnetic coil 4 can be corrected based on the value reflecting the change in the resistance value R2 of the electromagnetic coil 4, the control error caused by the change in the resistance value R2 of the electromagnetic coil 4 can be properly adjusted. Can be corrected.

Further, since the correction value C is obtained based on the voltage value E2 of the power supply 5, even if the voltage value E2 of the power supply 5 fluctuates, the control error can be properly corrected without being hindered by the fluctuation. .

[0010]

Embodiments of the present invention will be described with reference to the drawings. 1 and 2 are diagrams for explaining an embodiment of the present invention. In this embodiment, a diesel engine having an electronic governor is used. This diesel engine includes a fuel injection pump 11, and a fuel metering rack of the fuel injection pump 11 serves as a fuel metering unit 6. The fuel metering section 6 is urged by a start spring 19 in a fuel increasing amount r direction.

The electronic governor includes an engine speed setting means 1
2, an engine speed detecting means 13, a metering position detecting means 14, an electromagnetic actuator 1, a drive circuit 2, and a control means 3.

The structure and function of the electromagnetic actuator 1 are as follows. The electromagnetic actuator 1 is a linear solenoid, and includes a casing 15, an electromagnetic coil 4, a movable iron core 16, an output rod 17, and an urging spring 18. The urging spring 18 urges the movable iron core 16 in a direction to push it out of the electromagnetic coil 4. When the electromagnetic coil 4 is energized, an attractive force is generated in the direction of pulling the movable iron core 16 into the electromagnetic coil 4 against the urging force of the urging spring 18. The output rod 17 is fixed to the movable iron core 16 and protrudes outside the casing 15. The end of the output rod 17 is in contact with the fuel increasing amount r-side end of the fuel adjusting section 6 by the urging force of the start spring 19. The electromagnetic actuator 1 adjusts the fuel based on the balance between the attraction force of the movable iron core 16, the urging force of the urging spring 18, and the urging force of the start spring 19 corresponding to the amount of power P to the electromagnetic coil 4. The position of the measuring unit 6 is controlled.

The structure and function of the drive circuit 2 are as follows. The drive circuit 2 includes a power supply 5 and a switching element 20. A DC power source such as a battery is used as the power source 5, and the power source 5 energizes the electromagnetic coil 4 of the electromagnetic actuator 1. A transistor or the like is used as the switching element 20, and the amount of current P from the power supply 5 to the electromagnetic coil 4 is determined by the open / close ratio of the switching element 20 and the current value I of the drive circuit 2.

The structure and function of the control means 3 are as follows. The control unit 3 includes a calculation unit 21, a duty ratio setting unit 22, and a PWM wave generation unit 23. The calculating means 21 calculates a target set value of the fuel metering position based on the engine speed setting signal N1, the engine speed detection signal N2, and the metering position detection signal F. Based on this target set value, the duty ratio setting means 22 sets the duty ratio. Based on this duty ratio, PW
The M wave setting means 23 generates a PWM wave, opens and closes the switching element 20 of the drive circuit 2 at a ratio corresponding to the duty ratio, and controls the amount of power P from the power supply 5 to the electromagnetic coil 4.

The following problems occur only with the above configuration and function. That is, the temperature of the electromagnetic coil 4 changes based on a change in the ambient temperature of the electromagnetic coil 4 of the electromagnetic actuator 1 and a change in the amount of heat generated by the electromagnetic coil 4 itself.
Is changed from the reference resistance value R3,
If the current value I of the drive circuit 2 fluctuates and remains at the reference duty ratio, the amount of current P to the electromagnetic coil 4 deviates from the appropriate value,
An error occurs in the control of the fuel metering unit 6. Further, even if the voltage value E2 of the power supply 5 fluctuates from the reference voltage value E3, the same problem occurs. Note that the reference resistance value R3 refers to the resistance value of the electromagnetic coil 4 at a predetermined temperature, the reference voltage value E3 refers to a normal voltage value of the power supply 5, and the reference duty ratio refers to the reference value of the electromagnetic coil 4. When the power supply 5 takes the resistance value R3 and the power supply 5 takes the reference voltage value E3, the duty ratio is set so that the amount of current P to the electromagnetic coil 4 takes an appropriate value.

To solve this problem, the electronic governor is:
A resistor 7, a voltage detecting means 9 for the resistor 7, a voltage detecting means 10 for the power supply 5, and a correcting means 8 are provided.

The resistor 7 is provided in the drive circuit 2 and includes a power supply 5
And is connected in series with the electromagnetic coil 4 and is arranged at a location where the change in the ambient temperature is small. The resistor 7 has a reference resistance value R1 that is sufficiently smaller than the reference resistance value R3 of the electromagnetic coil 4, is less likely to generate heat, and has little change in resistance value due to a temperature change. This resistance 7
Is varied based on the fluctuation of the resistance value R2 of the electromagnetic coil 4 and the fluctuation of the voltage value E2 of the power supply 5.

The function of the correcting means 8 is as follows. The correction means 8 detects the detection signal V1 of the voltage value E1 applied to the resistor 7.
And a correction value C based on the detection signal V2 of the voltage value E2 of the power supply 5. As shown in FIG. 2, the process of obtaining the correction value C is performed with six steps of steps S1 to S8 as one cycle.

In step S1, it is determined whether or not a predetermined time has elapsed since the start of step S2 in the previous cycle. This set time is the cycle of the process for obtaining the correction value C. If it is determined in step S1 that the predetermined time has elapsed, in step S2, the voltage value E1 applied to the resistor 7 and the voltage value E2 of the power supply 5 are detected. In step S3, the current value I of the drive circuit 2 is calculated. In this calculation, the voltage value E1 applied to the resistor 7 is changed to the reference resistance value R of the resistor 7.
This is done by dividing by one.

In step S4, a voltage value E4 applied to the electromagnetic coil 4 is calculated. This calculation is based on the voltage value E of the power supply 5.
This is performed by subtracting the voltage value E1 applied to the resistor 7 from 2. In step S5, the resistance value R2 of the electromagnetic coil 4
Is calculated. This calculation is performed by dividing the voltage value E4 applied to the voltage value E4 applied to the electromagnetic coil 4 by the current value I. In step S6, a first correction term A is calculated. In this calculation, the combined resistance value R1 + R2 of the reference resistance value R1 of the resistor 7 and the resistance value R2 of the electromagnetic coil 4 is calculated as the combined resistance value of the known reference resistance value R1 of the resistor 7 and the known reference resistance value R3 of the electromagnetic coil 4. This is done by dividing by R1 + R3. In step S7, a second correction term B is calculated. This calculation is performed by dividing the known reference voltage value E3 of the power supply 5 by the voltage value E2 of the power supply 5. In step S8, a correction value C is calculated. This calculation is performed by multiplying the first correction term A and the second correction term B. The duty ratio setting means 22 of the control means 3 resets the duty ratio based on the correction value C.

The resistance value R2 of the electromagnetic coil 4 is equal to the reference resistance value R.
3 and the voltage value E1 of the power supply 5 maintains the reference voltage value E3, the first correction term A and the second correction term B
In each case, the value is 1, and the correction value C is also 1. In this case, the reset duty maintains the reference duty ratio, and the amount of current P to the electromagnetic coil 4 maintains an appropriate value.

Although the voltage value E2 of the power supply 5 maintains the reference voltage value E3, the resistance value R2 of the electromagnetic coil 4 fluctuates from the reference resistance value R3, and the combined resistance value R1 + R2 is 10 / (the combined resistance value R1 + R3). When it is nine times, the first correction term A becomes 10/9, the second correction term B becomes 1, and the correction value C becomes 10/9. In this case, the reset duty ratio is larger than the reference duty ratio, and the combined resistance value R
The amount of power P to the electromagnetic coil 4 decreased by the increase of 1 + R2 is corrected to an appropriate value.

The resistance value R2 of the electromagnetic coil 4 is equal to the reference resistance value R.
3, but when the voltage value E2 of the power supply 5 is reduced to 9/10 of the reference voltage value E3, the first correction term A becomes 1 and the second correction term B becomes 10/9. , The correction value C is 10/9. Also in this case, the reset duty ratio is larger than the reference duty ratio, and the voltage value E
2 is corrected so that the amount of current P supplied to the electromagnetic coil 4 decreased by the decrease of 2 becomes an appropriate value.

The combined resistance value R1 + R2 is equal to the combined resistance value R1 +
When R3 is 10/9 times and the voltage value E2 of the power supply 5 is reduced to 9/10 of the reference voltage value E3, the first correction term A is 10/9 and the second correction term B is also 10/9, and the correction value C becomes 100/81. Also in this case, the duty ratio to be reset is greater than the reference duty ratio, and the combined resistance value R1 + R2 is increased and the voltage value E of the power supply 5 is increased.
2 is corrected so that the amount of current P supplied to the electromagnetic coil 4 decreased by the decrease of 2 becomes an appropriate value.

Although the contents of the embodiment of the present invention are as described above, the present invention is not limited to this. For example, each value obtained in steps S3 to S8 may be obtained based on map data set in advance, without using calculation. When a constant voltage power supply is used as the power supply 5, the voltage detection means 10 of the power supply 4 becomes unnecessary, and the correction term B becomes unnecessary. Further, the correction value C may be multiplied by changing the ratio of A and B instead of multiplying the first correction term A and the second correction term B by the same ratio.

[Brief description of the drawings]

FIG. 1 is a block diagram of an electronic governor of a diesel engine according to an embodiment of the present invention.

FIG. 2 is a flowchart of a process for obtaining a correction coefficient for an electronic governor.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 electromagnetic actuator 2 drive circuit 3 control means 4 electromagnetic coil 5 power supply 6 fuel metering unit 7
Resistance, 8: correction means, E1: voltage value applied to resistance 7, E
2: voltage value of power supply 5, R2: resistance value of electromagnetic coil 4, C
… Correction value, P… Power supply to the electromagnetic coil.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Toshio Nakahira 3-8 Chikushinmachi, Sakai-shi, Osaka F-term in Kubota Sakai Coastal Plant (reference) 3G060 AB01 AC08 CA01 DA06 FA07 GA02 GA03 3G301 HA02 JA15 JA17 LB14 LC02 LC10 ND41 PB04Z PE01Z PG02A PG02Z

Claims (1)

[Claims] An electromagnetic actuator (1) and a drive circuit
(2) and control means (3). The electromagnetic actuator (1) includes an electromagnetic coil (4). The drive circuit (2) includes a power supply (5). The electromagnetic coil (4) is energized, and the control means (3) is controlled by the power supply (5) from the electromagnetic coil (4).
The electromagnetic actuator (1) is configured to control a metering position of a fuel metering unit (6) based on the amount of current P to the electromagnetic coil (4). An electronic governor for an engine includes a resistor (7) and a correction means (8), and the resistor (7) is provided in the drive circuit (2).
The voltage value E1 applied to (7) is configured to fluctuate based on the change in the resistance value R2 of the electromagnetic coil (4). The correction means (8) includes a voltage value E1 applied to the resistance (7),
The correction value C is obtained based on the voltage value E2 of the power supply (5). Based on the correction value C, the control means (3) controls the amount of electricity P Configured to compensate for
An electronic governor for an engine.