JPH02298645A - electronic governor - Google Patents

Abstract

PURPOSE:To maintain normal control also after the exchange of an actuator and a sensor by correcting the error between the output of the sensor and the position of a control rack after the exchange according to the difference of output, between before and after the exchange, at the time of starting an engine. CONSTITUTION:In an electronic governor, the position of a control rack A is changed by an actuator B and also detected by a sensor C. After an engine is started, the output of the sensor C is limited below a predetermined limit point output. In this case, the position of the control rack A is regulated by a positioning member D at the time of starting the engine. The output of the sensor C, when the control rack A is placed at regulated position, is memorized by a means E. At the time of correction mood, the abovementioned limit point output is increased or decreased by a means F according to the difference between the output of the sensor C and the content memorized by the means E under the condition that the control rack A is placed at the regulated position.

Description

DETAILED DESCRIPTION OF THE INVENTION +a+ Industrial Application Fields This invention relates to an electronic governor that achieves a predetermined rotational speed by changing the amount of fuel supplied to a diesel engine that drives a generator, etc. The present invention relates to an electronic governor configured as a pair of an actuator that displaces the control rack and a sensor that detects the position of the control rack.

(bl Conventional Technology-i) An electronic governor moves a control rack using an actuator such as a linear solenoid to increase or decrease the amount of fuel supplied to the engine.As a control method for rotating an engine at a constant speed using this electronic governor, , there is a system that detects the position of the control rack and drives an actuator so that this position matches the control position according to a predetermined engine speed.In this case, the actuator and sensor are integrated. However, if the displacement of the actuator is detected by a sensor, the actuator and sensor can be easily attached, and the structure can be simplified because they can be provided coaxially.

(C1 Problem to be Solved by the Invention) However, if the actuator and sensor are integrated, the position sensor will have to be replaced at the same time when the actuator is replaced due to failure, etc., and due to installation errors, the actuator, position sensor, and control rack may not be connected. The relative positional relationship of the engine may change before and after replacement, and due to individual differences between the engine and the control rack, errors may occur in the relationship between the output and the position of the control rack. There is a problem in that the output of the sensor when the control rack is located at the position where the actuator is located changes before and after the actuator is replaced, making it impossible to accurately control the amount of fuel supplied after the actuator is replaced.

The purpose of this invention is to make it possible to correct changes in the sensor output caused by errors in the mounting of the actuator and sensor and individual differences between the sensors after the actuator is replaced, and to control the fuel supply amount to a positive value even after the actuator is replaced. The goal is to provide an electronic governor that can be maintained.

(Means for Solving the Problems) The electronic governor of the present invention integrates an actuator that changes the position of the control rack and a sensor that detects the position of the control rack, and predetermines the output of the sensor after starting the engine. In an electronic governor that limits the output below a set limit point, the electronic governor includes a positioning member that defines the position of the control rack when the engine is started, and a storage means that stores the output of the sensor when the control rack is at the position determined by the positioning member. and a correction means for increasing or decreasing the limit point output according to the difference between the output of the sensor and the content stored in the storage means when the control rack is in the position specified by the positioning member during the correction mode. It is characterized by

That is, as shown in FIG. 1, the control rack is moved by the drive of the actuator, and the amount of fuel supplied to the engine changes. In order to prevent the engine from overspeeding, the control rack is designed to prevent the engine from exceeding its limit after starting. At startup, a large amount of fuel is required to start the engine, and the fuel is supplied beyond this limit point. The drive unit is connected to sensor S after the engine starts.
The actuator is driven so that the output does not exceed the limit point output SC stored in the storage means. The correction means changes the value of this limit point output Sc in the correction mode.

te1 Effect In this invention, the position of the control rack at the time of starting is defined by a positioning member. The storage means stores the output of the sensor when the control rack is in the starting position as the starting output Sk. In the correction mode, the sensor output S when the control rack is at the starting position defined by the positioning member is compared with the manual output Sk stored in the storage means, and the difference between the two is determined. The correction means changes the value of the limit point output Sc stored in the storage means based on this difference. Therefore, if the correction mode processing by the correction means is executed after replacing the actuator and sensor, the error between the control rack position and sensor output before and after replacement can be determined from the sensor output corresponding to the starting position. , the value of the limit point output Sc can be corrected according to this error.

(fl Embodiment FIG. 2 is a block diagram showing the configuration of a power generation device to which an electronic governor according to an embodiment of the present invention is applied.

The electronic governor 1 includes a fuel pump 2 driven by the rotation of an engine 21, a control rack 3 that sets the fuel injection amount of the fuel pump 2, a spring 7 that biases the control rack 3 in a direction to decrease the amount of fuel supplied, and a control. It consists of an actuator 4 that moves the rack 3 via the bushing rod 6 in a direction to increase the supply amount, and a sensor 5 that detects the displacement of the bushing rod 6. Fuel supplied from the fuel injection pump 2 is injected from a nozzle 12 into an intake manifold communicating with each cylinder of the engine 21. Crankshaft 24 of engine 21
The rotating shaft of the generator 25 is fixed to the.

The output of the sensor 5 is input to a controller 9 that controls the operation of the electronic governor 1, and outputs drive data to the driver 1) according to a program written in advance in a RAM included in the controller 9. The detection results of the electromagnetic pickup 22 and ammeter 23 are also manually input to the controller 9.

The electromagnetic pickup 22 detects the teeth of the ring gear 26 of the flywheel of the second engine, and inputs the detection pulse to the controller 9.

The controller 9 can know the rotational speed of the engine 21 by counting pulses within a predetermined period of time. Furthermore, the amount of power generated by the generator 25, that is, the load on the engine 21 can be determined from the output of the current 8123. The controller 9 determines whether the engine should be accelerated or decelerated from these input data, and determines control data for the actuator 4. The controller 9 refers to the contents stored in the memory IO when outputting this control data. The memory lO is battery hacked up and its memory areas MAL and MA are
2 is assigned to the storage areas of the limit point output Sc and the starting output Sk, respectively.

In order to prevent over-speeding of the engine 21, the controller I/roller 9 refers to the limit point output Sc stored in the memory 10 after the engine 21 is started, and limits the amount of fuel supplied. For this reason, the control rack 3 is at the limit point P after the engine starts.
It never exceeds I. However, since a large amount of fuel is required when starting the engine 21, the controller 9 allows the control rack 3 to move beyond the limit point PL during starting. In this case as well, the starting position P2 is defined by the force bolt 8 in order to prevent excessive fuel supply. This force bolt 8 is the positioning member of the present invention.

Actually, the position of the control rack 3 when the engine 21 is rotating at the maximum rotational speed is set as the limit point P1, and the force bolt 8 is screwed in until it comes into contact with the tip of the control rack 3 at this time.

Thereafter, the adjustment port 1-8 is returned by the amount increased at the time of startup, and sealed by a method such as applying paint. The output of the sensor 5 when the control rack 3 moves until it comes into contact with the force bolt 8 is stored in the memory area MA2 of the memory 10 as the starting output Sk.

FIGS. 4(A) and 4(B) are flowcharts showing a part of the processing procedure of the controller that constitutes the control section of the electronic governor.

When shipped from the factory, the engine 21 shown in FIG. 2 is rotated to the maximum rotation speed, and a switch SWI (not shown) included in the controller 9 is turned on. When the switch SW1 is turned on, the controller 9 converts the output S of the sensor 5 at this time into the limit point output S.
c in the memory area MAL of the memory IO (
nl→r12). Next, after rewinding the force bolt 8 by a predetermined amount to define the starting position P2, the control rack 3 is moved to the starting position P2 and the switch SW2, which is also included in the controller 9, is turned on. When the switch SW2 is turned on, the controller 9 controls the sensor 5 at this time.
The output is stored in the memory area MA2 of the memory IO as the starting output Sk. As described above, the limit point output Sc and the starting output Sk are set at the time of shipment from the factory.

Since the sensor 5 is integrated with the actuator 4, when the actuator 4 is replaced, the sensor 5 is also replaced at the same time. When the actuator 4 is replaced, a correction mode process shown in FIG. 4(B) is executed. That is, after replacing the actuator 4 with the sensor 5, the control rack 3 is moved to the starting position P2, and the switch SW (not shown) included in the controller 9 is moved.
Operate 3. When the switch SW3 is turned on, the controller 9 erases the value of the starting output Sk stored in the memory from the output S of the sensor 5 at that time, and calculates the difference X (
nll-n12). Next, the value of the limit point output Sc stored in the memory IO is set to the value obtained by adding the calculation result X (n l 3), and the value of the starting output Sk is set to the output S after the sensor (n l, 4 ), in the above sll 2
~rs l 4 is the processing of the correction means shown in FIG.

Through the above processing, it is possible to determine the error in the starting output of the sensor 5 before and after replacing the actuator 4, and to correct the limit point output Sc in accordance with this value. The controller 9 refers to the limit point output Sc corresponding to the new sensor 5 when outputting control data after the actuator 4 is replaced, so that the limit point P1 does not change before and after replacing the actuator 4. Accurate fuel supply control can be maintained.

In addition, when reading the starting output Sk at the time of factory shipment and in the correction mode, the voltage applied to the actuator 4 is increased with the engine 21 stopped. This can prevent the engine 21 from over-rotating. Further, in this embodiment, a power generation device has been described as an example of a device to which an electronic governor is applied, but any engine can be used as long as the fuel supply amount is controlled by an electronic governor.

(g) Effects of the Invention According to this invention, the error between the sensor output and the position of the control rack after the actuator and sensor are replaced can be corrected by the difference in output at startup before and after the replacement, Even after replacement, normal fuel supply amount control can be maintained.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the configuration of the present invention, FIG. 2 is a diagram showing the configuration of a power generation device to which an electronic governor according to an embodiment of the present invention is applied, and FIG. 3 is a diagram configuring the control section of the power generation device. The memory map of the main part of the memory, FIGS. 4(A) and 4(B) are flowcharts showing a part of the processing procedure of the control unit of the power generation device, and FIG. 4(A) shows the processing at the time of shipment from the factory. CB) in the same figure shows processing in the correction mode.l-electronic governor, 3-control rack, 4-actuator, 5-sensor, 8-adjustment port (positioning member), IO-memory (storage means), 21 -Engine. [Applicant: Kubota Iron Works Co., Ltd.]

Claims (1)

[Claims] (1) An actuator that changes the position of the control rack, a sensor that detects the position of the control rack,
In an electronic governor that limits the sensor output to below a predetermined limit point output after the engine starts, the electronic governor includes a positioning member that defines the position of the control rack at the time of engine startup, and a positioning member that defines the position of the control rack by the positioning member. storage means for storing the output of the sensor when the control rack is at the position specified by the positioning member; An electronic governor comprising: a correction means for increasing/decreasing the limit point output.