JPH01155040A - Engine controller - Google Patents

Abstract

PURPOSE:To ease a car body vibration and a body sensory shock attributable to a torque variation by operating external load at a time when the angular velocity of a crankshaft becomes almost minimized. CONSTITUTION:Operating timing and stopping timing are controlled to proper timing by a control unit 12 for an operating command and a stopping command of external load such as a compressor 5, an oil pump 6, an alternator 7 or the like. In brief, when the compressor 5 operates, it is controlled so as to be operated at a time when a variation in the angular velocity of a crankshaft becomes minimized. In addition, when actuation of the compressor 5 is stopped, it is controlled so as to stop the actuation when the angular velocity becomes almost maximized. With this constitution, a variation in the crankshaft angular velocity before and after the actuation of the external load becomes minimized, so that a car body vibration and body sensory shock attributable to a torque variation are thus eased.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an engine control device, and in particular to an engine control device that appropriately controls the timing of the start of operation of an external load driven by an engine, such as a compressor for a near conditioner. The present invention relates to an engine control device that alleviates torque shock.

[Prior art]

Conventionally, engine-driven near conditioners (
When operating an external load such as a compressor for an air conditioner (hereinafter referred to as an air conditioner) or an oil pump for power steering, the idle speed is controlled when the external load is activated to prevent engine rotational output fluctuations or engine stalls based on the external load. BACKGROUND OF THE INVENTION It is common practice to increase the idle speed of an engine by using an output correction means such as a device to increase the engine output.

However, with the engine output correction means described above, since the external load such as a compressor starts operating at the same time as the external load activation switch is turned on, there is a period of time until the engine output correction means operates and the rotational output of the engine actually increases. There were problems such as a drop in engine speed and engine stalling.

Therefore, for example, in the engine control device described in Japanese Patent Application Laid-Open No. 58-187550, by providing a delay means in the compressor operating circuit, the engine output correction means is operated at the same time as the air conditioner switch is turned on, and the engine output correction means is activated for a certain period of time. A system has been proposed in which the compressor is controlled to operate after the engine output has steadily increased.

[Problem that the invention seeks to solve]

In the engine control device described in the above-mentioned publication, the compressor starts operating after the engine output correction means operates and the engine output increases, so the problems such as the decrease in engine speed and engine stall as described above are avoided. Although this can be prevented, there is a problem in that large torque fluctuations and vehicle body vibrations occur as the compressor operates because there is no control over when the compressor operates.

In other words, the rotational angular velocity of the engine's crankshaft increases with each explosion stroke of each cylinder among multiple cylinders, and decreases from the end of this explosion stroke to the explosion stroke of the next cylinder. The rotational angular velocity of changes between the maximum value and the minimum value at a substantially constant period. Here, when an external load such as a compressor is activated, the rotational angular velocity will decrease to a certain predetermined angular velocity due to the load, but if the external load starts operating at the time when the angular velocity is at its maximum, There is a problem in that the amount of drop in angular velocity is the largest, and the output torque of the engine fluctuates greatly, causing vibrations to the vehicle body and significant bodily shock to the occupants.

[Means for solving problems]

The engine control device of the present invention includes an operation command detection means for detecting an operation command for an external load driven by the engine, an angular velocity detection means for detecting the angular velocity of the crankshaft of the engine, and an output from both of the above detection means. In response to this, when the operation command for the external load is detected by the operation command detection means, the control means operates the external load at a time when the angular velocity of the engine is approximately at its minimum.

[Effect]

In the engine control device according to the present invention, when the operation command detection means detects an operation command for an external load, the control means detects an angular velocity of the crankshaft that is approximately at a minimum based on the outputs from the operation command detection means and the angular velocity detection means. The external load is controlled so as to operate at the timing when .

The angular velocity of the crankshaft decreases due to the activation of the external load, but since the external load is activated at a time when the angular velocity of the crankshaft is approximately at its minimum, the amount of change in the angular velocity of the crankshaft before and after the activation of the external load is minimized, and the torque Vehicle body vibration and physical shock caused by fluctuations are alleviated.

〔Effect of the invention〕

According to the engine control device according to the present invention, as explained above, the operation of the external load is performed at a time when the angular velocity of the engine is approximately at its minimum, so that the amount of decrease in the angular velocity when the load is activated is suppressed to approximately the minimum. It is possible to reduce vehicle body vibration and bodily shock to passengers.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

Figure 1 shows the overall configuration of an automobile engine and its control device.The in-line 4-cylinder 4-cycle engine E includes a near conditioner (hereinafter referred to as air conditioner) compressor 5 and an oil pump for power steering. 6 and an alternator 7 that supplies electric power when charging a battery or operating an electric load such as a headlamp, and a drive that rotates integrally with the crankshaft is provided at the end of the crankshaft on the output side of the engine E opposite to the transmission. A pulley 1 is installed, and the compressor 5, oil pump 6, and alternator 7 are provided with drive pulleys 5a, 6a, and 7a, respectively, and the pulleys 5a, 6a, and 7a are connected to the healds 2, 3, and 4, and the idler pulley 2a, respectively. - It is connected to the drive pulley 1 via 3a and 4a, and the rotation of the drive pulley 1 drives the compressor 5, oil pump 6, and alternator 7, respectively, but these structures are different from the conventional one. Since it is similar to that commonly provided in automobile engines, detailed explanation will be omitted.

The above compressor 5 and oil pump 6 as external loads
A control unit 12 is provided to control the operation and stop of the alternator and the alternator. A compressor SW9 outputs a command signal, a PSSWIO outputs a command signal to start/stop the oil pump 6 when the steering wheel (not shown) is steered, and a compressor SW9 outputs a command signal to start/stop the oil pump 6 when the steering wheel (not shown) is turned. Accordingly, a signal is input from the alternator 5W11 which outputs an operation/stop command signal for the alternator 7, and a signal is also input from the crank angle sensor 8, which is provided in conjunction with the crankshaft of the engine E and detects a crank angle signal of the crankshaft. A signal is input, and the control unit 12 outputs a drive current (hereinafter referred to as a load operation signal, and OFF of the load operation signal is referred to as a load stop signal) to the compressor 5, oil pump 6, and alternator 7, respectively. It looks like this.

The control unit 12 includes a waveform shaping circuit that shapes the crank angle signal from the sensor 8, and an input that receives signals from this waveform shaping circuit and each SW 9, 10, and 11 and converts them individually into digital signals. An interface, a microcomputer consisting of a CPU, ROM, and RAM, an output interface, and drive circuits for driving the compressor 5, oil pump 6, and alternator 7, respectively, are provided, and the ROM contains a load described later. A control program for operation/stop control, etc. is manually stored in advance, and the RAM is provided with various memories (memory for storing data, etc.) necessary for executing the above control.

When the compressor 5 receives an actuation signal from the control unit 12, the electromagnetic clutch provided inside changes from the disconnected state to the connected state, and the rotation of the pulley 5a is transmitted to the drive shaft of the compressor 5, thereby driving the compressor 5. , At this time, a large rotational load is generated on the engine E. When the operating signal from the control unit 12 stops, the electromagnetic clutch becomes disconnected and the rotation of the pulley 5a is no longer transmitted to the drive shaft, so the operation of the compressor 5 stops and the pulley 5a becomes idling, causing the engine
The above-mentioned rotational load is eliminated.

The oil pump 6 is configured to pump oil when it receives an activation signal from the control unit 12, and the load on the oil pump 6 is particularly high when operating the steering wheel while the vehicle is running at low speed or stopped. An additional rotational load will be generated on the crankshaft of engine E.

The alternator 7 is of the battery sensing type,
To prevent overcharging of the battery (not shown) during light loads, such as when the electrical load has stopped operating, and overdischarging when a large electrical load is operating, a predetermined constant power is always supplied. However, when it receives an activation signal from the control unit I2 as the electric load operates, it is controlled to increase the field current through the regulator to increase the power generation capacity, and the engine E rotational load increases.

Therefore, the engine control device of this embodiment uses the controller 1-roll unit 12 to appropriately adjust the operation timing and stop timing in response to the operation command and stop command of external loads such as the compressor 5, oil pump 6, and alternator 7 as described above. This system reduces vehicle body vibrations and bodily shocks experienced by passengers caused by load activation and stoppage through timely control.

That is, to explain the case when the compressor 5 is operating as an example, as shown in FIG. 2, the rotation angle CA (crank angle CA) of the crankshaft of the engine E and its angular velocity when the compressor 5 is not operating As shown by the solid line in the figure, the relationship with ω is that every half revolution of the crank angle CA, one of the four cylinders goes into an explosion stroke, so the angular velocity ω rises, and this is repeated among the four cylinders in turn. Therefore, assuming that the engine speed is constant, the angular velocity ω changes periodically between the maximum value (2) and the minimum value (2). On the other hand, when the compressor 5 is operating, the angular velocity ω uniformly decreases overall compared to the state where the compressor 5 is not operating, as shown by the broken line in the figure, but there is a difference between the maximum value Va and the minimum value V3. For example, because the compressor 5 changes periodically between the angular velocity and Ba,
Decrease N (change N) in angular velocity ω due to operation of compressor 5
) is ΔVA = (V2 - V3) for point A, ΔVB = (Vl - V3) for point B, and the amount of change in angular velocity ω is maximum at point A, and at point B. is the minimum. In other words, the larger the amount of change in the angular velocity ω, the greater the vibration of the vehicle body and the bodily shock felt by the occupants, so the compressor 5
control to operate. When stopping the operation of the compressor 5, based on the same concept as above, if the operation is stopped when the angular velocity ω is the minimum, the amount of change in the angular velocity ω before and after stopping will be large, so when the angular velocity ω is approximately the maximum, Control to stop operation.

Hereinafter, a flowchart of the load operation/stop control routine performed by the control unit 12 will be described with reference to FIG. However, although the operation stop control of the compressor 5 will be explained here as an example, the same applies to the oil pump 6 and the alternator 7.

In the figure, 31 to S20 indicate each step, and the control is started when the engine E starts, and at Sl, the crank angle signal from the crank angle sensor 8 and the compressor SW
The load SW multiplication signal from 9 is read, and in S2 it is determined whether or not the load operating signal is currently ON for the compressor 5.
When the load operation signal is ON, that is, when the compressor 5 is operating, the process moves to S12 and the stop control of the compressor 5 is executed through steps 312 to S20, and when the load operation signal is not ON (the compressor 5 is stopped). (time), the process moves to S3, and the operation control of the compressor 5 is executed through steps 33 to S11.

In step S3, in the operation control of the compressor 5 from 33 to Sll, it is determined in S3 whether the compressor SW9 is ON or not, that is, whether or not the operation command signal for the compressor 9 is output, and whether or not the operation command signal is output. When there is no operation command signal, it returns to S1, and when the operation command signal is output, it returns to S1.
At step 4, the current crankshaft angular velocity ω1 is calculated from the rank angle signal, and then at 85, the previous crankshaft angular velocity ω is calculated. is read from the RAM data memory, and S6
The current angular velocity changes Δω, -ω, -ω. is calculated, and then in 87 it is determined whether the angular velocity change amount Δω1 is positive or not. If Δω1≧0, the process moves to S8 and Δω
, <0, the process moves to Sll and the previous angular velocity change amount Δω is obtained at Sll. is updated by Δω1 and returns to Sl. In S8, the previous angular velocity change amount Δω. is read from the RAM data memory, and then at 89 Δω. It is determined whether Δω is negative or not. If ≧0, it returns to Sl via Sll and Δω. In the case of <0, the control unit 12 shifts to SIO and outputs a load operation signal (drive current) to the compressor 5 to operate the compressor 5. That is, by determining the angular velocity ω of the crankshaft from the crank angle signal and further determining the amount of change Δω, the current amount of change Δ
The time when Δω1≧0 and △ωo<0 by comparing ω and the previous change amount △ω0, that is, the time when the angular velocity ω is at its minimum (
In other words, the load operation signal is output to the compressor 5 at the time indicated by point 0 in FIG. 3 when the engine enters the explosion stroke and the angular velocity ω begins to increase. Therefore, even if an operation command signal is output from the compressor SW 9 to the control unit 12 at the time indicated by the PON point in the figure, the load operation signal will not be output to the compressor 5 until the angular velocity ω reaches the 0 point, which is the minimum. First, since the operation of the compressor 5 is started after the 0 point, the amount of change in angular velocity before and after the operation of the compressor 5 is minimized, and it is possible to minimize the vehicle body vibration and bodily shock that occur when the compressor 5 is activated. I can do it.

On the other hand, to explain the control for stopping the compressor 5 in operation, if the result of the determination in S2 is that the compressor 5 is in operation, the process moves to S12, and in S12, the load SW multiplication signal from the compressor SW9 is turned OFF.
It is determined whether or not, and if it is not OFF, it returns to Sl,
If it is OFF, the process moves to S13, in which the current angular velocity ω1 of the crankshaft is calculated from the crank angle signal, and then in S14 the previous angular velocity ω is calculated. is loaded,
Next, in 315, the angular velocity change amount Δω, -ω1-ω0 is calculated, and the process moves to S16. In step 316, it is determined whether Δω1 is negative or not, and if it is not negative, the process moves to S20, in which the previous Δω0 is updated with Δω1, and Sl
If Δω1 is negative, the process moves to S17, where the previous Δω0 is read from the data memory of RA and M, and is sent to Sl.
to move to. In S1.8, it is determined whether Δω0≧0 or not, and if it is negative, the process returns to Sl via S20 (80).

If ≧0, proceed to S19 and control unit 1
2 outputs a load stop signal to the compressor 5 to turn off the load operation signal, and the compressor 5 stops. That is, if the compressor 5 is to be stopped, temporarily P in FIG. Even if the stop command signal is output from the compressor SW9 at the time of point 42, the load stop signal will not be output until the time when Δω is <0 and Δω0≧0, that is, the time at point D when the angular velocity ω is maximum under load. No output occurs, and a load stop signal is output at point D. Thereby, it is possible to minimize the amount of change in the angular velocity of the crankshaft due to the stoppage of the compressor 5, thereby reducing vehicle body vibration and body shock.

Incidentally, in the above flowchart, it goes without saying that the routine from 81 to S20 is repeated at every minute time. Also,
When an external load is activated during an idle state, the idle speed control device also controls the engine speed to maintain a predetermined idle speed, but since it is not directly related to the present invention, its explanation will be omitted. did.

In the above embodiment, a vertical four-cylinder engine was explained.
The present invention is not limited to this, but can also be applied to various engines such as a type 6 six-cylinder engine.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention. Fig. 1 is an overall configuration diagram of an engine and its control device, Fig. 2 is a diagram explaining the state of the crankshaft angular velocity of the engine, and Fig. 3 is a diagram showing the operation of the load. FIG. 4 is a flowchart of the load operation/stop control routine. E...Engine, 5...Compressor, 6...
Oil pump, 7. Alternator, 8. Crank angle sensor, 9. Compressor SW. 10...PSSW, 11...Alternator SW,
12...Control unit. Patent applicant Mazda Motor Corporation? ::%J
God i to heshi nan S to small, Y to i to the amount ratio S of

Claims (1)

[Claims] (1) An operation command detection means for detecting an operation command for an external load driven by the engine, an angular velocity detection means for detecting the angular velocity of the engine crankshaft, and an operation command detected by receiving outputs from both of the above detection means. 1. A control device for an engine, comprising: control means for operating the external load at a time when the angular velocity of the engine is approximately at its minimum when the means detects an instruction to operate the external load.