JPH03266728A - Constant speed running control device - Google Patents

Abstract

PURPOSE:To prevent both hunting and surge, to stop integration of car velocity deviation when an accelerator opening is less than a designated value by conducting the feedback control according to both a car velocity and a throttle opening. CONSTITUTION:A throttle driving means 50 is connected to a throttle valve 11, and a throttle opening detection means 13 is coupled thereto. At this time, in a controller 100, a deviation between the target speed and a correction value of the running speed is calculated. According to the integration value of the above deviation, the initial opening of the throttle valve 11 is corrected to obtain a target throttle opening, and a deviation between the target throttle opening and the current throttle opening is calculated. Further, according to the respective arithmetic results, the throttle driving means 50 is controlled in such a manner that the running speed agrees with the target speed. When a detection value of an acceleration opening detection means 37 connected to an accelerator pedal 34 becomes more than a preset value, the above integration for the car velocity deviation is stopped.

Description

Detailed Description of the Invention [Objective of the Invention] (Industrial Application Field) The present invention compares the traveling speed of a vehicle with a target speed, and adjusts the throttle valve to fMJ in order to make the traveling speed equal to the target speed. /Relating to a constant speed traveling device with closed drive.

(Prior Art) A constant speed cruise control device compares a traveling speed with a target speed and opens a throttle valve when the former is low, and closes the throttle valve when the former is high.

The throttle valve is driven to open and close by a negative pressure actuator that expands and contracts a diaphragm using, for example, negative pressure in an intake manifold. By communicating the internal space of the diaphragm with the intake manifold, the diaphragm retracts and the throttle valve is driven to open, and by communicating with the atmosphere, the diaphragm expands and the throttle valve is driven to close (for example, Japanese Patent Laid-Open No. 62-68138 Public bulletin).

The throttle valve opening degree is determined by the time ratio (duty) for alternately switching the diaphragm internal space between the intake manifold and the atmosphere, and communicating the intake manifold and the atmosphere. Alternatively, the throttle valve is driven to close in the R direction by an electric motor via an electromagnetic clutch.

In these throttle valve drivers, a current value is determined by current value control based on current duty control, and the throttle valve is driven at a position or speed corresponding to the current value.

The energizing current value is determined by the energizing time T within a predetermined cycle (duty is T/predetermined cycle x 100%), and is determined by M* based on the deviation of the traveling vehicle speed from the target vehicle speed and the integrated value of the deviation.
A value for making the difference O is calculated, and the throttle valve driver is energized based on this value. This IWiT at the time of energization is calculated using, for example, T=G (Vb-(VP+CT-A)) b: Memory vehicle speed (target vehicle speed) vP: Current vehicle speed A: Acceleration G: Vehicle speed deviation gain CT: Calculated by correction time, electromagnetic When the throttle valve is driven by a clutch and an electric motor, the motor is urged to rotate in the forward direction (throttle valve opening direction) when the energization time T is positive, and is urged to rotate in the reverse direction (in the closing direction) when T is negative.

An outline of this control is shown in FIG. To explain this,
Using the acceleration A, which is the differential value of the current vehicle speed Vp, obtain the preliminary phase vehicle speed V0CTXA, which is corrected by the advance phase, and combine this with the target vehicle speed v.
b is subtracted and further multiplied by the gain G to obtain the energization time T.

The throttle valve drive system, which has a gain of G1 (s) depending on the energization time T, changes the throttle valve opening (AP in FIG. 11 is the current throttle opening). Next, the vehicle system (engine-axle system) having a gain of G2(8) changes the vehicle speed VP by changing the throttle opening.

(Problem to be Solved by the Invention) In the above-mentioned system, constant speed control is performed by feeding back the current vehicle speed VP and performing advance phase compensation for the lag in the throttle valve drive system and vehicle system using acceleration A. It is insufficient to correct the lag in the throttle valve drive system and vehicle system using acceleration A alone, and if the correction time CT is used for tuning, if the correction time CT is small, hunting will occur in a long period and in a large width. If you increase the correction time CT to prevent hunting, a surge (minor movement) will occur.
becomes more likely to occur. In other words, it is thought that the above phenomenon occurs because the feedback time constant (M at the time of response) is large. In order to obtain a good feeling without such hunting, surge, etc., it is suppressed by adding an integral term to the above T calculation formula. However, when the integral term is added, the accelerator pedal is depressed and the vehicle accelerates, the deviation becomes negative (the current vehicle speed is higher than the target speed), and the integrated value becomes negative and increases. If the accelerator pedal is released when the integrated value reaches a large negative value.

In a constant speed cruise control system, since the current vehicle speed is considerably higher than the target vehicle speed, the deviation value becomes a large negative value, greatly lowering T, and the integrated value during acceleration due to accelerator pedal depression remains as a large negative value. Lower T further. Therefore, the vehicle speed decreases rapidly. This decline is
When the vehicle speed decreases below the target speed, the deviation value becomes positive and the vehicle stops, but since the integrated value remains as a negative value, the speed of increase in vehicle speed is slow until it becomes positive. When accelerating rapidly, an undershoot occurs in which the vehicle speed drops below the target speed when the accelerator pedal is released, and then rises to the target value at a relatively slow speed. The present invention aims to improve this type of problem.

[Structure of the invention]

(Means for Solving the Problems) A constant speed cruise control device of the present invention is coupled to a throttle valve (11) of a vehicle. Throttle drive means (SO)
; Throttle opening degree detection means (13, 101) that detects the opening degree (AP) of the throttle valve (11); Vehicle speed detection means (13, 101) that detects the opening degree (AP) of the throttle valve (11);
L, SW, Wag); Target speed (vb) and traveling speed (Vp) detected by the vehicle speed detection means (L511°Wag)
The deviation (Vb - vp) from the value (Vp + cr・A) corrected by the acceleration (A) and the correction coefficient (cr)
-CT-A)?
The initial opening degree (IAP) of the throttle valve (II) is determined by the target speed (vb) and the vehicle speed detection means (LSV, Mag).
The target throttle opening (TAP) is determined by correcting the accumulated value of the deviation (Vb - Vp) from the detected traveling speed (Vp).

A deviation (TAP - AP) between the target throttle opening (TAP) and the current throttle opening (AP) detected by the throttle opening means (13, 101) is calculated. Second
calculation means (101); output (Dl) of the first calculation means (101) and output (D2) of the second calculation means (101)
) and travel speed (Vp) corresponding to the sum (D1+02).
speed control means (101) that urges the throttle drive means (50) in a direction that matches the target speed (vb);
? Accelerator opening detection means (37, 100) detects the amount of depression of the accelerator pedal (34); and the detection amount of the accelerator opening detection means (37, 100) is a predetermined value (5%).
If the value exceeds the limit, the integration control means (1) stops the integration of the vehicle speed deviation (Vb - Vp) in the second calculation means (101).
01) ;

Note that symbols in parentheses indicate corresponding elements or corresponding numerical symbols in the embodiments shown in one drawing and described later.

(Function) According to this, the first calculation means (101) calculates the target speed (
The deviation between Vb) and the value obtained by correcting the traveling speed (Vp) is calculated. Further, the second calculation means (101) calculates the initial opening degree (IAP) of the throttle valve (II) by four target speeds (
The target throttle opening (TAP) is determined by correcting the deviation (vb - Vp) between the travel speed (Vb) and the traveling speed (Vp), and the target throttle opening (TAP) and the current throttle opening (AP) are calculated. ) is calculated. The speed control means (101) has a first calculation output (Dl)
and the second calculation output (DI) (DI + f)2)
Based on 4m, the traveling speed (Vp) is the target speed (Vb)
energizing the throttle drive means (50) in a direction consistent with .

Therefore, in effect, feedback control is performed using both speed and throttle opening parameters, and if the feedback amount based on speed is fRwl than before, and the correction time crh < tts, hunting occurs in a long period and in a large width. This solves the problem that if the correction time CT is increased to prevent this, surges (microtremors) are more likely to occur.

By the way, when the driver operates the accelerator to override, the vehicle speed deviation (vb - Vp
) by integrating the target throttle opening (TAP)
becomes small, and the undershoot becomes large when returning from override.

Therefore, in a preferred embodiment of the present invention, when the accelerator function exceeds a predetermined value (5%), the second calculation means (101)
The integration of the vehicle speed deviation (Vb -1ap) at is stopped. Therefore, the integrated value does not change when accelerating by pressing the accelerator pedal, but when the accelerator pedal is released! Since the IT calculation value is the value immediately before the accelerator operation (a relatively small value around 0), when the accelerator pedal is released, both the vehicle speed deviation and the integrated value will change to a value that allows the vehicle speed at that time to smoothly converge to the target vehicle speed. However, the above-mentioned undershoot does not substantially stop.

Other objects and features of the invention will become apparent from the following description of an embodiment with reference to one drawing.

(First Embodiment) Referring to FIGS. 2a and 2b, the main parts of the mechanism of the first embodiment of the present invention are shown in detail in FIG. 2a, and the appearance is simplified in FIG. 2b. An intake passage, which is an air flow path, of a throttle body 1 of an engine, and a throttle valve 11 are rotatably supported by a throttle shaft 12. A case 2 is integrally formed on the side surface of the throttle body 1 on which one end of the throttle shaft 12 is supported, and a throttle valve driver is assembled to the case 2 and the cover 3. Furthermore, a throttle sensor 13, which is part of the throttle valve driver, is mounted on the side surface of the throttle body 1 opposite to the case 2, on which the other end of the throttle shaft 12 is supported.

The throttle sensor 13 is a potentiometer that generates an analog electrical signal indicating the opening degree of the throttle valve 11, and its slider is connected to the throttle shaft 12. A movable yoke 43 is fixed to the other end of the throttle shaft 12. The throttle valve it is configured to rotate integrally with the movable yoke 43. The movable yoke 43 is a circular disk-shaped magnetic body with a shaft fixed to the throttle shaft 12, and each open end faces the fixed yoke 44, which is a magnetic body having approximately the same shape, and has side walls and details. are fitted with a predetermined gap in a state where they overlap in the axial direction. This fixed yoke 44 is fixed to the throttle body 1, and a coil 45 wound around a non-magnetic bobbin 46 is housed in a space formed between the shaft portion and the side wall.

A friction member 43a made of a non-magnetic material is embedded in the bottom surface of the movable yoke 43 around the throttle shaft 12, and is connected to the drive plate 4 via a clutch plate 42 made of a disc-shaped magnetic material.
The machines are placed facing each other.

The drive plate 41 is a circular plate-shaped body with a shaft in the center.
The details are rotatably supported around the throttle shaft 12. An external gear is integrally formed in a part of the drive plate 41, and is configured to mesh with external teeth formed in a small diameter portion of a gear 52, which will be described later. The aforementioned clutch plate 42 is coupled to the bottom surface of the drive plate 41 via a leaf spring 41a. The clutch plate 42 is biased toward the drive plate 41 by the leaf spring 41a, and is separated from the movable yoke 43 when the coil 45 is not energized.The gear 52 that meshes with the drive plate 41 has a small diameter portion and a large diameter portion. It has a stepped cylindrical shape, each of which is formed with an external cutout, and is rotatably supported on a shaft 52ajtl fixed to the cover 3. A motor 50 is fixed to the cover 3, and its rotating shaft is rotatably supported parallel to the shaft 52a. A gear 5I is fixed to the tip of the rotating shaft of the motor 50, and meshes with the external teeth of the large diameter portion of the gear 52. Motor 50 is a step motor.

When the motor 50 rotates and the gear 51 rotates, the gear 52 rotates, and the drive plate 41 meshing with this rotates around the throttle shaft 12# together with the clutch plate 42. At this time, if the coil 45 is not energized, the clutch plate 42 is separated from the movable yoke 43 by the urging force of the leaf spring 41a. That is, in this case, the movable yoke 43, the throttle shaft 12, and the throttle valve 11 are in a state where they can freely rotate independently of the drive plate 41. The coil 45 is energized and the movable yoke 43
When the fixed yoke 44 is excited, the clutch plate 42 is attracted toward the movable yoke 43 against the urging force of the leaf spring 41a due to the electromagnetic force, and comes into contact with the movable yoke 43.

As a result, the clutch plate 42 and the movable yoke 43 are frictionally engaged, and together with the action of the friction member 43a, both rotate in a connected state. That is, in this case, the drive plate 41. Clutch plate 42. The movable yoke 43, throttle shaft 12, and throttle valve 11 are integrally rotated by a motor 50 via gears 5], , 52.

An accelerator shaft 32 is rotatably supported by the cover 3 in parallel with the throttle shaft 12 and protrudes from the cover 3. Three accelerator links constituting a rotating lever are fixed to the protruding end of the accelerator shaft 32, and a pin 33a fixed to one end of the accelerator cable 33.
is locked to the tip of the accelerator link 31. A return spring 35 is connected to the accelerator link 31, and the accelerator link 3 and the accelerator shaft 32 are biased in the closing direction of the throttle valve 11. The other end of the accelerator cable 33 is connected to an accelerator pedal 34, forming an accelerator operation mechanism in which the accelerator link 31 and the accelerator shaft 32 rotate around the axis of the accelerator shaft 32 in response to the operation of the accelerator pedal 34. .

An accelerator plate 36 in the form of a plate is fixed to the left end of the accelerator shaft 32.

A round hole is made to rotatably support the right end of the additional intermediate shaft 24, and the right end of the intermediate shaft 24 enters this round hole. The left end of the intermediate shaft 24 is rotatably supported by the throttle body 1. A plate-shaped throttle plate 21 is rotatably mounted on the intermediate shaft 24 so as to face the accelerator plate 36 .

The throttle plate 2I consists of a small diameter part and a large diameter part fixed to the intermediate shaft 24, and external teeth are formed on the outer surface of the large diameter part. The external teeth of this throttle plate 21 mesh with the external teeth formed on the aforementioned movable yoke 43, and the movable yoke 43 rotates in response to the rotational drive of the throttle plate 21, and the throttle body physically connected thereto. shaft 12
and the throttle valve 11 is configured to rotate.

The throttle plate 21 has a step formed at the connection portion between the small diameter portion and the large diameter portion, and an end cam is formed on the outer peripheral side surface. One radial side of the large diameter portion is arranged to face a stopper (not shown) provided on the case 2, thereby restricting rotation of the throttle plate 21.

A bottle 23 is fixed to the large diameter portion of the throttle plate 21.

One end of the return spring 22 is locked to the shaft portion of the throttle plate 21, and the other end is locked to a bottle implanted in the case 2. Therefore, the throttle plate 21 is biased by the biasing force of the return spring 22 in a direction in which the side surface of the large diameter portion comes into contact with the case 2 . That is, the throttle plate 21 is urged by the return spring 22 in the direction in which the throttle valve 11 is closed.

The accelerator plate 36 consists of a disk portion whose center portion is fixed to the accelerator shaft and arm portions extending in the radial direction.

The portion of the disk portion that continues to the arm portion has a radius, a recess is formed, and an end cam is formed on the outer circumferential side surface. The arm portion is arranged such that one side in the direction of rotation faces a stopper (not shown) provided on the case 2, and the other side faces the bin 23 of the throttle plate 21.

That is, when the accelerator plate 36 rotates counterclockwise and the arm comes into contact with the pin 23 of the throttle plate 21, the accelerator plate 36 and the throttle plate 21
are constructed so that they rotate together. Note that normally, when the throttle plate 21 is not urged to rotate by the electric motor 5o and the accelerator is not depressed at all, the arm portion of the plate 36 is in contact with the bottle 23. FIG. 2 shows this state.

The accelerator plate 36 is urged clockwise by the urging force of the return spring 35. Also, accelerator plate 3
6 is implanted with a bottle 36c extending in the axial direction of the accelerator shaft 32.

An accelerator sensor 37 is fixed to the outer periphery of a bearing portion of an accelerator shaft 32 formed on the cover 3 . The accelerator sensor 37 is a potentiometer, and a pin 36c is engaged with its slider. As a result, the accelerator sensor 37 generates an analog electrical signal indicating the rotation angle of the accelerator shaft 32.
0, and a solder board 71 is connected to the printed wiring board 70.

A limit switch 60 interlocked with the throttle plate 21 and the accelerator plate 36 is connected to the case 3 via a stay.
and is electrically connected to the printed wiring board 70. The limit switch 60 is a normally closed switch that is switched from closed to open by the cam part of the throttle plate 21 when the opening degree of the throttle valve 11 reaches the upper limit, and is used to detect whether the throttle valve 11 has reached its upper limit. It is used. The limit switch 60 is inserted into the electric coil 45 of the electromagnetic clutch 40 and the power supply line of the electric motor 50, respectively.
When 0 is opened, the electric coil 45 and the electric motor 50 are de-energized.

In the throttle valve driver of this embodiment described above, a yoke 43 is fixed to the throttle shaft 12, and the external teeth of the yoke 43 mesh with the external teeth of the throttle plate 21. The throttle plate 21 is rotatably attached to an intermediate shaft 24 that can freely rotate with respect to the accelerator shaft 32, and is rotated clockwise (second direction) by a return spring 22.
(Fig.) is forced to rotate at all times. With the above combination,
When the throttle valve 11/throttle shaft 12/yoke 43/throttle plate 21 are in a rotationally interlocking relationship and the electric coil 45 of the electromagnetic clutch 40 is de-energized (clutch disconnected) when the accelerator pedal 34 is not depressed, Due to the force of the return spring 22, the throttle valve 11 is at its minimum opening (idling opening: Fig. 2).

When traveling at a constant speed, the electric coil 45 is energized, the drive plate 41 is frictionally coupled to the yoke 43, and the drive plate 41 is further rotated counterclockwise (FIG. 2) by the positive rotation bias of the electric motor 50. Throttle valve 11
The opening becomes larger.

When the drive plate 41 is rotated clockwise by urging the electric motor 50 to rotate in the opposite direction, the opening degree of the throttle valve 11 becomes smaller. A throttle sensor 13 coupled to throttle shaft 12 generates an analog signal indicative of throttle valve opening.

The opening of the throttle valve 11 is at the mechanical maximum value (at this time, the throttle plate 21 hits the mechanical stopper)
Immediately before the electric motor 50
The positive rotational bias of the electromagnetic clutch 40 is stopped, and the electromagnetic clutch 40 is de-energized. When the electromagnetic clutch 40 is de-energized, the electromagnetic clutch 40 is disconnected and the throttle valve 11 is returned to the closing direction by the force of the return spring 22, but when the limit switch 60 is returned to the closed position due to this return, the electromagnetic clutch 40 is closed. The energization of the electric coil 45 is resumed, and the electromagnetic clutch 40 is then returned to the closed position, and the rotation of the throttle valve 11 in the closing direction by the return spring 22 is stopped. Through such an operation, when attempting to drive the throttle valve 11 to or beyond the mechanical maximum opening, the opening of the throttle valve 11 is held at the opening just before the mechanical maximum opening. That will happen.

When the electromagnetic clutch 40 is energized and the electric motor 50 is used to set the opening degree of the throttle valve 11 to a certain degree, even if the accelerator pedal 34 is depressed, the accelerator plate 36 engages with the pin 22 of the throttle plate 21. The throttle valve 11 is not operated by depressing the accelerator pedal 34 within a range in which the amount of rotation of the accelerator plate 36 is smaller than the amount of rotation of the throttle plate 2I.

When the accelerator pedal 34 is depressed, the amount of rotation of the accelerator plate 36 increases, and the accelerator plate 36 moves toward the bin 22.
When the throttle plate 2I comes into contact with the accelerator plate 36, the opening degree of the slot valve 11 becomes the opening degree relative to the accelerator depression amount. As the accelerator depression amount further increases, the opening degree of the throttle valve 11 increases. When the accelerator pedal is released slightly, the opening degree of the slot valve 11 becomes slightly smaller due to the force of the return spring 22.

In this way, when the vehicle is not in the constant speed mode, or even in the constant speed mode, when the accelerator depression amount is within a range greater than the rotation amount of the throttle plate 21, the opening degree of the throttle valve is determined by the accelerator depression amount.

By the way, the electric throttle valve opening/closing drive mechanism described above is controlled by the electric control circuit shown in FIG. This electric control circuit is a microcomputer (hereinafter referred to as CPU).
) 101 and various drivers, converters,
It consists of an input circuit, switches, etc. Each component is supplied with a voltage Vat from the battery BTT, a constant voltage Vcci via a first constant voltage power source cps1, and/or a constant voltage Vcc2 via a second constant voltage power source CPS2. Although a detailed power supply line is not particularly shown in FIG. 1, this is because the supply of voltages v6 and Veal requires only connection of battery BTT, and is constantly supplied as long as battery BTT is connected. Also,
Supplying the voltage Vcc2 further requires turning on the main switch MSW, but as shown in FIG. 1, the only elements to which this voltage Vcc2 is supplied are the CPU I0I and the alarm lamp ALP.

The CPU10I uses the constant voltage Vcc2 from the second constant voltage voltage WKCPS2 to set the standby mode and return to the normal mode. This standby mode is
This is a power saving mode in which all input/output ports are set to high impedance, only the previous register state and RAM contents are retained, and software operations are stopped. CPU101
This standby mode is set when the constant voltage VC (:2) is no longer applied, but if this mode is set, software operation will be stopped, so hardware control is required to return to normal mode. The port for doing this is the control port Iss, and when the constant voltage Vcc2 from the second constant voltage power supply CPS2 is applied to the control port Iss, the standby mode returns to the normal mode.

The functional operation of each part will be explained below.

PWM counter 102 is given PWM data D and clock pulses from CPU 101 . This PWM
Data is given as positive or negative values.

The symbol indicates the biasing direction of the motor 21, and the magnitude indicates the on-duty. That is, when the PWM counter 102 is given PWM data D other than zero, it changes the PWM pulse to a high level H (energization instruction), and if the sign is positive, the energizing direction control signal goes to the H level, and vice versa. If so, set the energizing direction control signal to low level L and start counting clock pulses, and then, when the count value becomes equal to the absolute value of PWM data D, set the PWM pulse to low level L (de-energization instruction). Turn around.

The PWM pulse of the PWM counter 102 and the energizing direction control signal are given to the motor driver 103. The motor 50 of the electric throttle valve opening/closing drive mechanism described above is connected to the motor driver 103, and if the direction control signal is at the H level, the motor driver 103 urges the motor 50 to rotate normally while the PWM pulse is at the H level. However, if the direction control signal is at L level, the motor 50 is energized in reverse while the PWM pulse is at H level. The operation of this motor driver 103 is monitored by a monitoring circuit 104.

The aforementioned limit switch εO is inserted in series in the energizing line of the motor 50. The switches No. 29 restrict rotation of the throttle valve 12 in the forward rotation direction beyond its limit. That is, as described above, the forward rotation of the motor 50 is transmitted to the throttle shaft 12 via the electromagnetic clutch, and the throttle shaft 12 rotates in the direction to wind up the wire 42, and the rotation exceeds the throttle opening angle corresponding to the upper limit. , the limit switch 60 opens to prevent the forward rotation of the motor 50 and disengage the clutch, and the return spring 22 causes the throttle shaft 12 to rotate in the reverse direction, causing the limit switch 6 to open.
0 is closed, the clutch is engaged and the motor 50 is urged to rotate in the forward direction. If the rotation of the throttle shaft 12 falls below the angle corresponding to the lower limit of throttle opening, the reverse urging is prevented by a mechanical stopper (not shown). .

The solenoid driver 105 is connected to the coil 45 of the electric throttle valve opening/closing drive mechanism described above. The solenoid driver 105 energizes this coil 45 upon receiving an electromagnetic clutch energization instruction from CPLllol.
When receiving an instruction to deenergize the electromagnetic clutch, it is deenergized.

A normally closed brake switch BSW2 and a limit switch 60 are interposed in the energizing line of the coil 45 in conjunction with depression of a brake pedal (not shown). When the brake pedal is depressed, the brake switch BSW2 opens its contacts and cuts off the energizing line of the coil 25.

Further, the limit switch 60 regulates the rotation limit of the output throttle shaft 12, as described above.

Therefore, when the brake pedal is depressed or when the rotation of the throttle valve 11 reaches the upper limit, the coil 25
is immediately deactivated. Note that the solenoid driver 105
The operation of the brake switch BSW2 and the operation of the brake switch BSW2 are monitored by a monitoring circuit 106.

When the lamp driver 107 receives a lamp activation instruction from the CPUl0I, it activates the alarm lamp ALP (constant voltage Vc
(conditional on supply of c2). This warning lamp ALP is installed in the meter panel of the automobile (not shown), and the 6A/D converter 108 that serves as a backlight for the message ``Please have the auto drive inspected'' is connected to the CPU 10.
When the chip is selected by I, the potentiometer 13
Converts the detected voltage of A into digital and returns it to CPU10I.
When the /D converter 109 is chip-selected by the CPUI O1, it digitally converts the output voltage of the F/V converter 110 and returns it to the CPUIOI.

When a chip is selected by CPUl0I, A/D converter 11.1 digitally converts the voltage detected by tilt sensor 113 and returns it to CPUlOI. Also, when the A/D converter 120 is selected, it becomes 1 meter 37.
The detected voltage is digitally converted and returned to CPUl0I.

The F/V converter 110 is a converter that converts one frequency into a voltage, and here, the reed switch LSW is
The frequency of a signal generated by turning on/off in response to the magnetism of a rotating permanent magnet Mag coupled to an output shaft (not shown) of the transmission is converted into a voltage. In other words, the F/V converter 110 outputs a voltage signal proportional to the vehicle speed.

Input circuits 114, 115. 116, 117 and 11
8, each CPUl0I is a switch I SW
* (: S W - B S W 1. This is an input interface for reading the on/off status of S S W and R8W.

The switch ISW is a normally open idling switch that detects the idling rotation of an engine (not shown), and the switch C8W is a normally open clutch switch that is linked to depression of a clutch pedal (not shown).

The switch BSW is the brake switch BSW mentioned above.
Like 2, it is linked to the depression of a brake pedal (not shown), but this is a normally open brake switch, to which a brake lamp BLP is connected in series. In addition, since the voltage across the brake switch BSW1 is input to the input circuit 116, even if the brake lamp BLP or the fuse inserted in series with these is disconnected, the brake switch BSWl cannot be turned on or off. can be detected.

The switch SSW is a manually operated set switch, and the operation of this switch instructs execution of constant speed driving control based on the vehicle speed when the switch is turned from on to off. Switch R5W is also a manually operated resume switch, but operation of this switch changes the memorized vehicle speed (if constant speed driving control has been canceled, the vehicle speed before cancellation). This is an instruction to execute speed running control.

An off-board diagnosis tool (hereinafter referred to as ODT) 119 is connected as necessary during repair. This ODT 119 is equipped with 1 display, operation keys, etc.
Inputting instructions for outputting diagnosis data and canceling abnormal mode to CPUl0IK, and
Diagnosis data from I is displayed.

FIG. 3 shows an outline of the control operation of the microcomputer 101 shown in FIG. 1, and FIGS. 4 and 5.

6, 7, 8 and 9a show details of the subroutine or interrupt processing routine shown in FIG. 3.

See Figure 3. microcomputer (hereinafter referred to as CPU)
When the power is turned on (Sl:S means the step or subroutine of the flowchart, and the number indicates the step number or subroutine number attached to the flowchart; hereinafter the same meaning), the initial setting, that is, the port state Mtl setting is performed. .

Clear the memory, initialize parameters, etc. (S2).

After completing the initial setting, the CPU 10I repeatedly executes the processes 83 and below at a cycle of about 5 Qmsec.

In S3, the status of the input boats PI to P6 is read. Next, in S4.85.86 or S7, it is determined whether the brake switch BSW, clutch switch CSW, set switch SSW, or resume switch R8W is on. investigate. Brake switch BSW
is on (S4) or clutch switch C8W is on (
S5), set O to register S88),
If set switch SSW is on (S6), set 2 to register S (39), resume switch R5
If W is on (S7), 3 is set in register S (S10).

Then, depending on the contents of register S (811).

"Standby processing J (S12), r constant speed control processing" (S1
3) Branch to r set processing J (S14) or resume processing J (815) and return to input port reading (S3). Thereafter, this operation is repeatedly executed in a loop.

Note that even if fuse FS2 is blown, switch BSW
In order to detect the operation, the CPU 101 determines that the switch BSW is turned on both when the input port P2 becomes a high level H and when the input port PL becomes a low level L.

The external interrupt (S16) will be explained with reference to FIG.

In this example, the external interrupt occurs every time the vehicle speed detection reed switch LSW is turned on, that is, at the fall of the signal applied to the input port P6.

When an external interrupt occurs (S I 6), register R4
Increment the contents of (1). As a result, if the content of register R4 is less than 4 in step 2, the process returns to the main routine, but if the content of register R4 is 4 or more, C
PUl0I reads the contents of its internal hardware counter CN.

The counter CN always counts clock pulses of a predetermined period apart from the operation of the CPUl0I, but is cleared every four times an external interrupt occurs. Therefore.

This counter CN has a reed switch LS for vehicle speed detection.
A value corresponding to the time when four pulses are output from W is counted. A permanent magnet placed near the reed switch LSW has four poles, and when it rotates once, the reed switch LSW outputs four pulses. In other words, the counter CN measures the time it takes for the speedometer cable to rotate once.

The periodic data obtained by reading the contents of the counter CN is stored in register R5, and when the contents of register R4 becomes 4 or more, the contents of register R4 are cleared (3), and the periodic data stored in register R5 is , calculates the vehicle speed, and stores the result in register RO (4).

When these processes are completed, the contents of the counter CN are cleared and restarted (5), and the process returns to the main routine.

Next, timer interrupt processing (S17) will be explained with reference to FIG. In this example, a hardware timer provided internally in the CP UIOI is used to generate a timer interrupt request at predetermined intervals. When the timer interrupt request occurs, timer interrupt processing (S17) shown in FIG.
Execute.

In timer interrupt processing (517), register RA.

Increment R, (11). These registers are used as independent timers.

Every time the value of register RA exceeds the predetermined value NA (12)
, stores the contents of register R1 in register R2, and stores the contents of register RQ in register R1 (13). Since this process is performed every time the value of the register RA exceeds the predetermined value NA, the latest vehicle speed and the previously measured vehicle speed are stored in each register R2 and R1, respectively. Furthermore, the result of subtracting the value of register R2 from the value of register R1 is stored in register Ra, and the contents of register RA are cleared to O (14). This process is performed periodically at predetermined time intervals determined by the value of NA. The contents of register R3 are used as acceleration data in the duty calculation described later.

Note that the register R, which is incremented in the timer interrupt processing (S17), is used as a timer for measuring the on time or off time of various switches. Also, although not shown in FIG. 3, there is a brake switch BSW and a clutch switch C5W.

Set switch SSW or resume switch R8W
When starting from the off state and changing to the on state, the value of the register RB is cleared to 0. This allows the elapsed time since each switch was turned on to be determined.

Next, "standby processing J (512)" will be explained with reference to FIG.
2) Clear the integral value register TAP (23) and return to the main routine. When set in this way, the electromagnetic clutch 40 is off (disconnected), so the throttle valve 1
2 and the motor 50 are mechanically disconnected, and the throttle valve 12 has an opening degree corresponding to the amount of depression of the accelerator pedal 34.

Next, the "set process J (S14) will be explained with reference to FIG. 7. When the set switch SSW is turned on.

First, the electric coil 45 of the electromagnetic clutch 40 is set to ON (31), thereby mechanically connecting the rotating shaft of the electric motor 50 to the throttle valve (2). however,
While the switch SSW is on, the electric motor 50 is off and the throttle valve 12 is not driven.
Continue the opening when W was turned on.

If the sect switch SSW remains on (
32), then immediately return to the main routine. Therefore, the vehicle speed accelerates or decelerates depending on the vehicle load. When the set switch SSW changes from on to off (32), the contents of the register Ro at that time, that is, the current vehicle speed, are stored in the vehicle speed memory R, 33), and the register S is set to 1 (33).
34).

When 1 is set in the register S, from the next loop processing, [constant speed control processing] (
S13) is executed.

Next, referring to FIG. 8, "Resume processing J (S 15
). When the resume switch R5W is turned on, the electric coil of the electromagnetic clutch 40 is first energized (41
). This mechanically connects the rotating shaft of the electric motor 50 to the throttle valve.Secondly, the overflow of the resume timer is checked (42).The resume timer is cleared when the resume switch R8W is turned on for the first time. This refers to register RI!.If it does not overflow, return to the main routine.

Until the resume timer overflows.

When the electric coil 45 of the electromagnetic clutch 40 is on, the throttle valve 12 is mechanically coupled to the rotating shaft of the electric motor 50, but since the electric motor 50 is off, the throttle valve opening does not change, but the running load of the vehicle The vehicle speed either maintains a constant value, increases or decreases depending on the situation. When the resume timer overflows (43), register R
Store the contents of o in the vehicle speed memory RH (45). In the next loop process, r constant speed control process J (S13)4. :
Pass through.

If the resume switch R8W is turned off before the resume timer overflows, the vehicle speed previously stored in the vehicle speed memory R is read and the vehicle starts driving at a constant speed. However, if the resume timer overflows, Since the contents of the vehicle speed memory RH are updated to the current vehicle speed, the vehicle enters constant speed driving at the current vehicle speed.

Next, the constant speed running control of this embodiment will be explained with reference to FIG. 1O. Using acceleration A, which is the differential value of the current vehicle speed VP, calculate the preliminary phase vehicle speed VP + CTXA, which is corrected for the advance phase,
This is subtracted from the target vehicle speed vb, and the gain G
The first energization time T is obtained by multiplying by . During the first energization, the throttle valve drive system having a gain of Gl (11) due to rIIJT changes the throttle valve opening (AP in FIG. 10 is the current throttle opening).

Next, the vehicle system (engine-
(axle system) changes the vehicle speed VP by changing the throttle opening.

In other words, constant speed control is performed by feeding back the current vehicle speed Vp and using acceleration A to advance and compensate for the delay in the throttle valve drive system and vehicle system.
It is insufficient to correct the lag in the throttle valve drive system and vehicle system by just using the correction time CT.If the correction time CT is small, the engine will hunt with a large paddle for a long period, and the hunting will be suppressed. If the correction time CT is increased in an attempt to prevent this, surges (11j movement) are more likely to occur. In other words, the feedback time constant (
This is thought to occur because the response time (response time) is large. In order to obtain a good feeling without such hunting, surge, etc., the calculation formula D==Vb-(Vp+
C (XA) is suppressed by adding an integral term.

That is, in this embodiment, by providing a feedback loop of the ACT opening degree, changes in vehicle speed are estimated and corrected based on the ACT opening degree.

In FIG. 10, IAP is the value of the initial ACT opening determined by the vehicle speed, and the initial ACT opening IAP is corrected by integrating the vehicle speed deviation vb-VP and multiplying by an integral gain KI. Initial ACT opening degree IAP is memorized vehicle speed (target vehicle speed)
This is the ACT opening degree when driving on a flat road in vb,
The required ACT opening degree changes when the load changes, such as when going uphill. This is obtained by integrally correcting Vb-Vp.

The corrected target ACT opening degree TAP is subtracted from the cursed ACT opening degree AP which is the output of the ACT system, and its deviation TAP-A
The gain G is added to the first deviation TAP-AP for which P is calculated.
Multiplying by P yields the second output. The sum of the first and second outputs is calculated and becomes the output. That is, when the output is positive, the ACT system rotates in the forward direction by AP determined by the gain Gl (S), and when the output is negative, it rotates in the reverse direction. The distance between vehicles is accelerated or decelerated by the operation of ACT.

By the way, when an integral term is added, the accelerator pedal is depressed and the vehicle accelerates, the deviation becomes negative (the current vehicle speed is higher than the target speed), and the integrated value becomes negative and increases.

If the accelerator pedal is released when the integrated value has reached a large negative value, in the constant speed cruise control system, the current vehicle speed is considerably higher than the target vehicle speed, so the deviation value becomes a large negative value and T
In addition to greatly lowering T, the integrated value during acceleration due to accelerator pedal depression remains a large negative value, which further lowers T. Therefore, the vehicle speed decreases rapidly.

This decrease stops when the vehicle speed decreases below the target speed because the deviation value becomes positive.

Since the integrated value remains negative, the vehicle speed increases slowly until it becomes positive. That is, when the vehicle accelerates temporarily by pressing the accelerator pedal, an undershoot occurs in which the vehicle speed drops below the target speed when the accelerator pedal is released, and then increases to the target value at a relatively slow speed.

Therefore, in this embodiment, when the opening degree of the accelerator reaches a predetermined value or more, the second calculation means stops integrating the vehicle speed deviation.

FIG. 9a shows "
A control flowchart of constant speed control processing J (S13) is shown. Here, first, a preset loop gain G, a target vehicle speed vb, a vehicle speed vP at that time, a preset compensation time constant CT (of the throttle valve 11) Using the time constant (time constant that compensates for the delay in vehicle speed change with respect to opening change) and the acceleration A at that time, perform the calculation G (Vb - (Vp + CT-A)), and first calculate the PWM data Di (within a 50tsec cycle). (51) Next, calculate the throttle opening (initial throttle opening) IAP required to drive at the target vehicle speed stored in the memory R on a flat road. (52), but instead of this calculation, step 33
(Fig. 7) or 45 (Fig. 8), digital conversion of the detected value of the throttle opening sensor 13 and writing processing of the converted data to the register IAP are added, step 52 is omitted, and the calculation subroutine is 54, data in register TAP may be used as IAP.

Next, digitally convert and read the signal from the accelerator opening sensor 13, and check whether the accelerator depression amount is 5% or more (with accelerator pedal depression) in terms of 2 throttle valve opening53) or less than 5% ( Calculate accelerator pedal opening TAP (54), target throttle opening TAP is initial throttle opening IAP, target keyaki speed vb
, the current vehicle speed V P +integral gain Kl is used to calculate the following equation.

TAP=IAP+KIJ (Vb-Vp)dtIf the depression amount of the accelerator opening sensor 13 is 5% or more in terms of throttle valve opening in step 53, the process proceeds to step 55 without calculating the target throttle opening TAP. ．． To calculate the target throttle opening TAP. Since there is an integral term for the vehicle speed deviation, when the accelerator opening sensor 13 detects that the accelerator is not depressed (5% or more), the integration is stopped.

In step 505, GP (TAP-AP)
Calculate WM data D2. Here, GP is the deviation gain, and AP is the throttle valve opening detected by the potentiometer 37. Note that if the accelerator opening degree is 5% or more and the target throttle opening degree TAP is not calculated, TAP remains at the value immediately before the accelerator pedal depression.

The sum of the PWM data DI and the PWM data D2 is calculated and given to the controller 100.

The polarity of this data D is the rotation direction of the electric motor 50 (10:
forward rotation/-reverse rotation), and the absolute value of the value is 50
Specify the energization time. In addition, the absolute value of D is 2w5ec
In the following cases, this is given to the controller 100 as D=0 (motor stopped).

[Since the constant speed control process J (513) is executed in the 50m5ecQ period, the data D is given to the controller 100 in the 50m5ec period. Upon receiving this data D, if D=0, the controller 100 causes the motor 5o to rotate in the reverse direction (throttle valve closing direction) when the polarity is negative, and when the polarity is positive, the controller 100 causes the motor 5o to rotate in the reverse direction (throttle valve closing direction). A rotation (throttle valve opening direction) energizing current is applied, a proper time is measured from the start, and when the time reaches the absolute value of D, the energization is stopped. As a result, the electric motor 5o is energized with a duty of 750 m5ec, an absolute value of 100XD.

(Second Embodiment) The second embodiment differs from the first embodiment only in the content of the D operation shown in FIG. 9a, so only this part will be described below. FIG. 9b shows the contents of the arithmetic processing of the PWM data D in the second embodiment. In the second embodiment, when accelerator pedal depression is detected in step 53, the PWM data 01 is converted to PWM data D without calculating the target throttle opening degree TAP, and the controller 1. Output to OO.

That is, in the D calculation of the second embodiment, the PWM data D is calculated using D1+D2 during normal constant speed specification, and only DI is used as the control data D when the driver depresses the accelerator pedal. Therefore, in this second embodiment, while the accelerator pedal is depressed, the throttle valve 12 is opened and closed by the electric motor 50 only in response to the vehicle speed deviation. In this case, if the opening of the throttle valve 12 due to the depression of the accelerator pedal is larger than that caused by the electric motor 50, the opening degree will be the same as that due to the depression of the accelerator pedal. In any case, the integration of the vehicle speed deviation is stopped while the accelerator pedal is being depressed.

(Third Embodiment) Similar to the second embodiment, the third embodiment differs only in the Dffl calculation flowchart shown in FIG. 9a of the first embodiment, so only the different parts will be described below. 9th c
The figure is a flowchart showing the contents of calculation of PWM data D in the third embodiment. In this case as well, when depression of the accelerator pedal is detected, the output is set to Dl and the integration of the vehicle speed deviation is stopped as in the second embodiment. In the third embodiment, it is further checked whether the vehicle speed deviation vb-Vp is -2.0 km/h or more when the accelerator pedal is not depressed58), and if so, D=DI+D2 is calculated. Output. Vehicle speed deviation vb-VP is -2.0k
Similarly to the case where the accelerator pedal is depressed, D2 is not calculated and D=01 is output when the value is less than +w/h. In other words, the integration of the vehicle speed deviation is stopped. This means that when the vehicle speed deviation is /JX, the vehicle speed can be sufficiently and smoothly converged to the target speed simply by correcting the opening corresponding to the vehicle speed deviation, but if the value becomes too large, it may cause undershoot or overshoot. This is to suppress the increase in the integrated deviation value.

(Example 4) In all of the above-mentioned first to third examples, the accelerator pedal 34
The accelerator opening sensor 37 is linked to the accelerator opening sensor 37, and it is determined whether to continue or suspend (suspend) the integration of the vehicle speed deviation based on the detected value of the accelerator opening sensor 37, but whether or not the accelerator pedal 34 is depressed is a problem. The throttle opening/closing drive I! (40
, 50) is determined by the pedal 34.
AP) is large, which can be detected by comparing TAP and AP. Therefore, in this fourth embodiment, as shown in step 59 of FIG. 9d, the check in step 53 of the third embodiment is changed to ``AP - TAP
%? ", and the accelerator opening sensor 37 is omitted. The other parts of the fourth embodiment are the same as those of the third embodiment.

〔Effect of the invention〕

As described above, according to the present invention, the first calculation means (101)
calculates the deviation between the target speed (vb) and the value obtained by correcting the traveling speed (Vp), and the second calculating means (101) calculates the initial opening degree (IAP) of the throttle valve (11) to determine the target speed. Deviation (vb-νP) between (vb) and traveling speed (Vp)
Target throttle opening (TAP) is corrected by the integrated value.
Then, the deviation (Tap - AP) between the target throttle opening (TAP) and the current throttle opening (AP) is calculated. Further, the speed control means (101) has a first calculation output (
DI) and the second calculation output (Dl) (DI+02)
Based on this, the throttle drive means (50) is biased in a direction in which the traveling speed (Vp) matches the target speed (Vb).

Therefore, in effect, feedback control is performed using both the speed and throttle opening parameters, and when the amount of feedback based on speed is limited compared to the past, and the correction time CT is small, hunting occurs with a long period and large width, and hunting is suppressed. This solves the problem that surges (11 motions) are more likely to occur if rFnCT is increased during correction to prevent this.

In addition, when the driver operates the accelerator to override, the target throttle opening (AP) becomes smaller by integrating the vehicle speed deviation (Wb-1p) in the second calculation means, and the undershoot becomes larger when returning from override. However, according to the present invention, the accelerator opening degree is set to a predetermined value (5%).
When this happens, the second calculating means (101) stops integrating the vehicle speed deviation (Wb - Vp).

Therefore, the integrated value does not change when accelerating by pressing the accelerator pedal, and when the accelerator pedal is released, the integrated value is the value immediately before the accelerator operation (a relatively small value around 0). Both the deviation and the integrated value transition to values that allow the vehicle speed at that time to smoothly converge to the target vehicle speed, and the aforementioned undershoot does not substantially stop.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an electrical control circuit according to a first embodiment of the present invention. FIG. 2a is a longitudinal cross-sectional view showing the mechanical part of the first embodiment of the present invention. FIG. 2b is a simplified perspective view of the mechanism section of the first embodiment. 3, 4, 5, 6, 7, 8, and 9a show the microcomputer 1 shown in FIG.
2 is a flowchart showing the control operation of No. 01. FIG. 9b is a flowchart showing the parts of the second embodiment of the present invention that are different from the first embodiment. FIG. 9c is a flowchart showing parts of the third embodiment of the present invention that are different from the first embodiment. FIG. 9d is a flowchart showing the parts of the fourth embodiment of the present invention that are different from the first embodiment. The first oWI is a block diagram showing a feedback system for throttle valve opening control of the constant speed cruise control device of the present invention. FIG. 11 is a block diagram showing a feedback system for throttle valve opening control of a conventional constant speed cruise control device. 1: Throttle body 2 = Case 3: Cover 11: Throttle valve 12: Throttle shaft I3: Throttle sensor (throttle opening detection means) 2
1.21p: Throttle plate 22: Return spring 23: Pin 24: Intermediate shaft 3
1: Accelerator link 32: Accelerator shaft 33: Accelerator cable 34: Accelerator pedal 35: Return spring 36
: Accelerator plate 37: Accelerator sensor (accelerator opening detection means) 40: Electromagnetic clutch 41
: Drive plate 42 : Clutch plate 4
3P: Movable yoke 44: Fixed yoke
45: Electric coil 50: Armature (throttle drive means) 51, 52: Gear 60: Limit switch
70 niblint wiring board 71: electrical lead 101: microcomputer (first calculation means, second
means of calculation. Throttle opening detection means. Accelerator opening detection hand R. integration control means, speed control means) 102: PIiM counter 10
3: Motor driver 104, 106: Monitoring circuit
105: Solenoid driver 107: Lamp driver

Claims (1)

[Scope of Claims] Throttle drive means coupled to a throttle valve of a vehicle; Throttle opening detection means for detecting the opening of the throttle valve; Vehicle speed detection means for generating an electrical signal according to the speed of the vehicle; a first calculation means for calculating the deviation between the target speed and a value obtained by correcting the traveling speed detected by the vehicle speed detection means using acceleration and a correction coefficient; A second throttle opening is corrected by an integrated value of the deviation from the detected traveling speed, and calculates a deviation between the target throttle opening and the current throttle opening detected by the throttle opening detecting means. a calculation means; a speed control means for urging the throttle drive means in a direction in which the traveling speed matches the target speed in accordance with the sum of the output of the first calculation means and the output of the second calculation means; Accelerator opening detection means for detecting the amount of depression of the accelerator pedal; and integration control means for stopping the integration of the vehicle speed deviation in the second calculation means when the detection amount of the accelerator opening detection means exceeds a predetermined value. Constant speed driving control device.