JPH0232841Y2 - - Google Patents

Description

[Detailed description of the invention] (A) Industrial application field The present invention is used in an engine control device, particularly in a diesel engine drive generator, etc., to control the engine to an idle state or an accelerator state depending on the presence or absence of a load on the engine. When automatically switching operation between the engine and the engine, the accelerator-controlled electric motor is used for the switching, and the motor drive circuit is disabled due to a change in the load condition on the engine while the motor is rotating. The present invention relates to an engine control device that has a function to prevent the engine from being turned off as desired.

(B) Problems to be solved by conventional techniques and ideas In engine control systems where a generator is driven by a diesel engine, there is a glow state that preheats the engine and a start state that starts the engine. The engine is configured to be controlled by a key switch having at least an on state in which the engine continues to rotate and an off state corresponding to stopping the engine.

In such an engine-driven power generation device,
When an abnormality occurs in the hydraulic system or other parts, the engine is controlled to stop, but the hydraulic system or other parts may appear to be in an abnormal state immediately after the engine starts, so the applicant has taken this into consideration. We proposed the above engine stop device (publication number 57-50509). However, recently, so-called slow-down control has been developed to reduce energy consumption by automatically returning the engine to idling when the load on the generator (and therefore the engine load) is reduced. Functions were added, and it was considered to apply the configuration related to the above proposal to an engine control device with the above slow-down control function (Utility Application No. 58-30659 and Utility Application No. 58-39139). ).
The content of the latter application will be described below, and the problems to be solved by the present invention will be clarified.

FIGS. 2 and 3 together constitute one drawing showing an embodiment of the present invention, and FIG. 4 shows the configuration shown in FIGS. 2 and 3 in blocks for ease of understanding. A block diagram is shown.

In FIG. 2, 1 is a battery for starting the engine, and 2 is a key switch, which has a glow state, a start state, an on state, and an off state. 3 is an idle solenoid, 4 is a relay for energizing the idle solenoid, and 5, located at the lower left end of Figure 2, is an auxiliary generator installed separately from the main generator driving the engine, which generates AC voltage when the engine is rotating. 6 is a first photocoupler for detecting engine rotation, 7 is a second photocoupler for detecting engine rotation, and 8 is a relay for controlling when an abnormality occurs.

When the key switch 2 is set to one of the glow state, on state, and start state, the voltage of the battery 1 is applied to the power line shown, and the idle solenoid 3 is energized as described later. Ru. Then, when the engine reaches an idling state, an alternating current voltage is generated in the auxiliary generator 5 mentioned above, and the photocouplers 6 and 7 are turned on, respectively. The turning on of the photocoupler 6 is used to control the idle solenoid, and the turning on of the photocoupler 7 is notified to the slow down drive circuit shown in FIG. 3, as will be described later, and thereafter a preparation state for putting the engine in the accelerating state is created.

In FIG. 3, 9 is a slow down drive circuit, 10 is an accelerator solenoid, 11 is an accelerator solenoid energizing relay, 12 is an engine load detection section, 13 is a time limit circuit for engine startup, 1
4 represents a relay control circuit.

The operation will be specifically described below with reference to FIGS. 2 and 3.

[A] When the key switch is in the start state.

(1) The voltage of the battery 1 is applied to the power line shown in the figure, and the voltage is supplied to the terminal 15 at the right end center in the figure 2, and the relay 11 shown in the figure 3.
A voltage is applied to the contact part of.

(2) By applying voltage to terminal 15,
Transistor 16 inserted in series with relay 4 is turned on, relay 4 is energized, and idle solenoid 3 is energized.

(3) At this time, the abnormality control relay 8 is kept in a non-energized state. That is, for a while after the engine is started (after the idle solenoid 3 is energized), the transistor 17 inserted in series with the relay 8 remains off even if an abnormal condition occurs, as will be described later. It is configured so that it is maintained.

(4) As the idle solenoid 3 is energized, the engine is started and the illustrated auxiliary generator 5 is activated.
When an alternating voltage appears at , photocouplers 6 and 7 are turned on, respectively.

(5) When the photocoupler 6 is turned on, the transistor 18 is turned on, then the transistor 19 is turned on, the transistor 20 is turned off, and charging of the capacitor 21 is started. When the terminal voltage of the capacitor 21 reaches a predetermined value, that is, after a predetermined period of time has passed after the engine is started, the output of the NOR element 22 becomes in a state where it can generate a logic "0".

(6) Under this condition, if, for example, the pressure in the hydraulic system drops abnormally or the water temperature becomes abnormal, the Schmitt trigger circuit (having hysteresis) consisting of NAND elements 23 and 24 will be activated. The NOR element 25 operates, the transistor 26 is turned on, the above-mentioned transistor 17 is turned on, and the relay 8 is energized. The results will be discussed later, but here we will explain that once a predetermined period of time has elapsed after the engine has been started, control to deal with abnormal conditions in the hydraulic system etc. becomes effective, and even if an abnormality is detected until then, It can be assumed that this will also be invalidated.

(7) When the photocoupler 7 mentioned above is turned on, the transistor 27 is turned on, and then the transistor 28 is turned on, and the voltage at the terminal 15 is passed through the transistor 28 to the slow down drive circuit 9 shown in FIG. It is led to terminal 29. That is, the slow down drive circuit 9 is notified that the idle state has been entered.

(8) As a result, battery voltage is applied to the power supply line 31 via the resistor 30,
The time limit circuit 13 for engine startup is activated.
That is, a voltage is applied to the input terminal of the comparator 32, and the comparator 32 generates a logic "1" to keep the transistor 33 in the ON state until the capacitor C is charged, but when the capacitor C is completely charged. and comparator 34
The transistors 35 and 36 are turned on and off depending on the presence or absence of a load detection signal from the engine load detection section 12.

(9) That is, in the engine load detection section 12,
A Hall effect element is used, and when a load occurs, it causes the voltage of the capacitor 37 to drop rapidly, and the comparator 34 issues a logic "1",
Turn on transistors 35 and 36. This energizes the relay 11 and energizes the accelerator solenoid 10. That is, the engine is caused to shift from an idle state to an accelerator state. Furthermore, when a predetermined period of time determined by the time limit circuit 13 has elapsed after the engine has been started, the control based on the output from the engine load detection section 12 becomes effective, and when a load occurs, the engine is automatically shifted to the accelerator state.

(10) Under the accelerator state, when the load is reduced, the capacitor 37 starts charging, and when the terminal voltage of the capacitor 37 reaches a predetermined value, the comparator 34 outputs a logic "0". That is,
Transistors 35 and 36 are turned off and relay 1
1 is removed, accelerator solenoid 10
The engine is no longer energized and the engine automatically returns to idle.

[B] When the key switch is on.

(11) The key switch 2 is configured to automatically enter the on state when the key switch 2 is pulled to the above-mentioned start state and then released.

(12) The operation of the key switch when it is in the on state is not substantially different from the state after the engine has been started in the start state, within the range shown in FIGS. 2 and 3. Then, when the engine is under load, the slow-down drive circuit is activated.

(13) When the engine is stopped and the key switch is left in the on state, if a predetermined period of time has elapsed, the terminal voltage of the capacitor 39 is applied via the resistor 38 located in the upper center of FIG. reaches a predetermined level. As a result, the transistor 42 is turned on via a Schmitt trigger circuit (with hysteresis) composed of NAND elements 40 and 41 (however, when the engine is running, the photocoupler 6 is turned on). , so transistor 42 does not turn on). Thereby, the transistor 16 inserted in series with the relay 4
is turned off, the relay 4 is deenergized, the idle solenoid 3 is deenergized, and unnecessary current from the battery 1 is prevented from flowing through the solenoid 3.

[C] When the key switch is in the glow state.

(14) As mentioned above, if the key switch 2 is undesirably left on, the idle solenoid 3 is deenergized after a predetermined period of time. However, the glow state in key switch 2 corresponds to the state in which the engine is preheated.
In this case, it is desired to energize the idle solenoid 3 at the same time as preheating the engine.

(15) For this reason, when placed in a glow state,
The voltage of the battery 1 is applied to the terminal 43 located on the upper left side of FIG. 2.

(16) As a result, the transistor 44 is turned on, and the charge in the capacitor 39 described in connection with operation 13 above is discharged. As a result, the terminal voltage of the capacitor 39 does not rise, and the transistor 42 is not turned on as in the case of operation 13 above. That is, until desired
It becomes possible to preheat the engine.

[D] When an abnormality occurs after the engine starts.

(17) As mentioned above, if a predetermined period of time has elapsed after the engine has been started, if an abnormality occurs in the hydraulic system or water temperature after this point, the above operation 6 will be performed.
Transistor 26 can now be turned on, as described in connection with FIG.

(18) When the transistor 26 is turned on, the transistor 17 inserted in series with the relay 8
is turned on, and the relay 8 is energized.

(19) As a result, the on state of the transistor 17 is maintained, and the battery voltage is applied to the connection point 45 located at the lower center in FIG.

(20) As a result, the transistor 42 is forcibly turned on via the diode 46, and as a result, the idle solenoid 3 is turned off.

(21) Also, the transistor 49 is forcibly turned on via the diode 47. As a result, the transistor 27 is turned off, the transistor 28 is turned off, and the battery voltage supplied to the terminal 29 of the slow-down drive circuit 9 shown in FIG. 3 disappears. Therefore, the accelerator solenoid 10 shown in FIG. 3 is turned off.

(22) As in operations 20 and 21 above, the engine is forced to stop by forcibly turning off the idle solenoid 3 and the accelerator solenoid 10 together.

(23) When the battery voltage is applied to the connection point 45 as described above, the voltage is applied to the resistor 5 via the diode 48.
Battery voltage is applied to 0. As a result, whereas the electric charge in the capacitor 52 was previously discharged via the diode 51 and the resistor 50, the diode 51 is turned off and the capacitor 52 starts to be charged.

(24) When the voltage of the capacitor 52 increases and reaches a predetermined level, the transistor 56 is turned on via a Schmitt trigger circuit (with hysteresis) composed of NOR elements 53 and 54.

(25) When the transistor 56 is turned on, the transistor 1 that has been kept in the on state until then is turned on.
7 is forcibly turned off. As a result, relay 8
is deenergized, and the battery voltage that was being supplied to transistor 42 via diode 46, to transistor 49 via diode 47, and to resistor 50 via diode 48 is dissipated. That is, it is reset to the expected state. Needless to say, care must be taken to ensure that the engine remains stopped for a sufficient amount of time from the time the engine is stopped in operation 22 until the reset state is reached as described above. Needless to say.

FIG. 4 shows a block diagram in which the configurations shown in FIGS. 2 and 3 are expressed in blocks for easier understanding. Codes 1, 2, 3, 5 in the diagram
9,10,15,43,Oil press,Water temp
corresponds to FIG. 2 or 3. Also 57
is the diesel engine to be controlled by this invention,
58 represents an engine-driven main generator, and 59 represents a regulator.

It may be considered that the relay drive circuit 60 shown in FIG. 4 mainly corresponds to the units 4, 16, etc. shown in FIG. Further, the rotation detection circuit 61
The illustrated units 6, 7, 18, etc. mainly correspond to this. The starting delay circuit 62
9, 20, 21 etc. are mainly supported. The relay release and hold circuit 63 connects the units 40, 4
1, 42, 46, etc. are mainly supported. The power supply circuit 64 for the slow down circuit is connected to the unit 2.
7, 28, 47, 49 etc. are mainly supported. The abnormality detection circuit 65 connects units 8, 17, 2
3, 24, 22, 25, 26, etc. are mainly supported. The stop delay circuit 66 includes the units 48,
50, 51, 52, 53, 54, 56, etc. are mainly supported. The activation delay circuit 67 is mainly supported by units 38, 39, etc. Further, the activation delay release circuit 68 corresponds to the unit 44 and the like.

When the start state, on state, or glow state is applied by the key switch 2, the idle solenoid 3 is energized by the relay drive circuit 60. When the engine 57 is thereby started, an alternating current voltage is generated from the auxiliary generator 5, and the rotation detection circuit 61 detects this fact. The start delay circuit 62 activates the relay release and hold circuit 63 for a while after the AC voltage is generated.
is prohibited from operating undesirably in response to instructions from the abnormality detection circuit 65. In addition, the slow-down circuit power supply circuit 64 operates from the time when the AC voltage is generated.
The slow down drive circuit 9 is notified of this fact.

After the engine enters the normal operating state, the prohibited operation by the start delay circuit 62 is stopped, and when the abnormality detection circuit 65 detects an abnormality, the relay release and hold circuit 63 activates the relay drive circuit 60 and slows down. - The down circuit power supply circuit 64 is notified of this, and the energization of the idle solenoid 3 is cut off, and even if the accelerator solenoid 10 is energized, it is forcibly cut off. As a result, the stop delay circuit 66 is activated.
After a sufficient period of time for the engine to properly stop, the relay release and hold circuit 63 returns to the desired state.

Although the conventional engine control device is configured as described above, an accelerator control electric motor has been adopted as an accelerator drive unit in place of the accelerator solenoid 10 shown in FIG.
This may be because the motor can be designed to require less energy per unit time than the solenoid, which operates instantaneously, by only being driven for a predetermined period of time. However, when replacing it with a motor as described above, the motor changes from the idle state to the accelerator state and/or
Alternatively, while the accelerator state is being switched to the idle state, the state of the load on the engine may change and the power to the motor may be turned off, and countermeasures for this are essential.

(C) Means for solving the problems The present invention aims to solve the above problems, and has the following structure. That is, (i) a motor rotation sensor is provided that determines whether or not the accelerator control electric motor is currently rotating.

(ii) Provide means for holding the motor in an operating state based on the output from the sensor during rotation, which controls the motor depending on the presence or absence of a load on the engine.

(D) Embodiment FIG. 1 shows the configuration of an embodiment of the slow-down drive circuit used in the present invention. Reference numeral 9 in the figure,
11, 12, 13, 14, 29, 30, 31, 3
2, 33, 34, 35, 36, 37, etc. correspond to those in FIG. Further, 69 is an accelerator control electric motor unit, 70 is a motor rotation sensor, and 7
1 is a motor current introduction terminal, 72 is a motor rotation signal output terminal, 73 and 74 are transistors, respectively;
5 represents a diode, 76 a motor, and 77 a limit switch.

The motor rotation sensor 70 detects the presence or absence of a motor armature current using a Hall effect element, and outputs a rotation signal to the output terminal 72 while the current is present, turns off the transistor 73, and turns off the transistor 73. 74 is turned on.

As explained in connection with FIG. 3 above, when a load is applied to the engine, the charge in the capacitor 37 is discharged and the transistor 35 is turned on.
The relay 11 operates, the contacts close downward from the state shown in FIG. 1, the motor 76 starts rotating, and operates to pull a lever (not shown) to drive the engine to the accelerator state. Further, when the load on the engine is removed while the engine is in the accelerator state, charging of the capacitor 37 is started, and when the charge of the capacitor 37 reaches a predetermined value, the relay 11 is reset and the contacts are in the state shown in FIG. Close upwards like this. The motor 76 then starts rotating in reverse and operates to push a lever (not shown) to drive the engine to an idle state.

However, if the load on the engine changes while the motor 76 is switching the operating state of the engine from one state to the other as described above, the following will occur. That is, a. While the engine is being switched from the idle state to the accelerator state, the capacitor 37 shown in FIG. 1 is discharged, and the contacts of the relay 11 are closed downward. Under this condition, if the load on the engine is removed, the capacitor 37 begins to be charged. Then, when the capacitor 37 is charged to a predetermined amount, the contact point of the relay 11 is switched upward. As can be seen from this, even if the load on the engine is removed during the transition from the idle state to the accelerator state, there is a time margin of, for example, about 6.5 seconds until the capacitor 37 is charged. During this time, the motor 76 finishes switching to the accelerator state. Then, the motor 76 enters an operation of switching to an idle state. That is, in this case, the motor 76 will not be undesirably stopped mid-rotation.

b. While the engine is being switched from the accelerator state to the idle state, the capacitor 37 shown in FIG. 1 is in a charged state and the relay 11
The contacts are closed upwards. Under this condition,
If a load is applied to the engine, the capacitor 37 is immediately discharged, and the contact point of the relay 11 is switched downward. As can be seen from this, if a load is generated on the engine during the transition from the accelerator state to the idle state, the contacts of the relay 11 are immediately switched, and the motor 76 is undesirably stopped mid-rotation. Something happens.

In the embodiment shown in FIG. 1, a motor rotation sensor 70 is provided which detects the motor armature current while the contacts of the relay 11 are closed upward. When the motor is rotating, the sensor 70 issues a rotating signal to turn off the transistor 73 and keep the transistor 74 on. That is, even if a load on the engine occurs, the base of transistor 35 continues to be held at a low level.
When the motor 76 reaches an idle state, the transistor 73 is turned on, the transistor 74 is turned off, and the relay 11 is activated in response to the output from the comparator 34.

(E) Effect of the invention As explained above, according to the invention, even if the load on the engine suddenly changes while the accelerator control electric motor is rotating, the motor will stop mid-way. No more stuffing away.

[Brief explanation of drawings]

FIG. 1 shows the structure of an embodiment of a slow-down drive circuit used in the present invention, and FIGS. 2 to 4 show the structure of a conventional engine control device on which the present invention is based. In the diagram, 1 is the battery, 2 is the key switch, and 9
is a slow down drive circuit, 11 is a relay, 12
76 represents an accelerator control electric motor, and 70 represents a motor rotation sensor.

Claims (1)

[Scope of utility model registration request] A key switch is provided which has at least a start state for starting the engine, an on state for continuing engine rotation, and an off state for stopping the engine, and the key switch is configured to adjust the battery voltage in response to the start state and the on state. an idle drive unit that is energized and shifts the engine to an idle state; and an idle drive unit that shifts the engine to an accelerator state when a load is applied to the engine under the idle state and returns the engine to the idle state when no load is applied; In an engine control device equipped with a slow-down drive circuit having an accelerator drive unit that returns the engine, a drive voltage is continuously applied to the accelerator drive unit for a predetermined period of time to maintain speed between an idle state and an accelerator state. In addition to using an accelerator control electric motor that switches the operation of the accelerator control electric motor, a motor rotation sensor that determines whether the accelerator control electric motor is rotating is provided. Accordingly, the present invention is characterized in that a circuit for controlling the motor is provided with an operating state holding means for maintaining the motor control in the motor operating state depending on the presence or absence of the load while the motor rotation sensor is emitting a rotating signal. engine control device.