JPS59168236A - Vehicle speed controller - Google Patents

Abstract

PURPOSE:To enable to retain stored vehicle speed data even when a power source is cut off accompanied by the stoppage of an engine and enhance practicality, by providing a memory data protecting means for protecting a vehicle speed memory and the contents thereof against cut-off of a power source. CONSTITUTION:An electronic controller 10 including a CPU is provided, a runaway-detecting circuit 20 is connected to a resetting terminal of the CPU, while a vehicle speed detecting lead switch SW2, a clutch switch SW3, a stop switch SW4, a setting switch SW5 and a resuming switch SW6 are connected to other input terminals of the CPU through interface circuits IF1-IF5, respectively. In addition, a stand-by voltage generating circuit 50 including a constant voltage circuit Z1 is connected to the CPU so that data stored in the vehicle speed memory in the CPU can be protected when the power source is cut off. Solenoids SL1, SL2 in a throttle-driving means are controlled in accordance with the data stored in the vehicle speed memory.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vehicle speed control device that stores the speed of a vehicle and automatically maintains the vehicle at the memorized speed.

Generally, this type of device detects the current vehicle speed as a number of pulses, and obtains an analog voltage proportional to the number of pulses as a vehicle speed signal. When the driver reaches a desired vehicle speed, he operates a constant speed travel set switch to set (store) the vehicle speed signal at that time in the memory circuit. The speed control device refers to the set vehicle speed signal as a reference voltage for one of the comparator circuits, and adjusts the opening degree of the throttle valve in a direction such that the difference becomes zero based on the difference between it and the current vehicle speed. This type of constant speed vehicle traveling device is known from Japanese Patent Laid-Open No. 53-127991 filed by the same applicant and other publications.

By the way, if you use this type of device, once you set the constant vehicle speed, the device will automatically control the vehicle speed, reducing the burden on the driver.However, with conventional devices, the driver frequently changes the vehicle speed. This was quite cumbersome for the driver as it required configuration.

That is, even if the driver only needs one specific vehicle speed as the memorized vehicle speed, the memorized vehicle speed is cleared every time the engine is stopped.

Each time the vehicle is driven, the vehicle speed setting (memory operation) must be readjusted. Additionally, vehicles generally travel at a speed of 40km/h or 60km/h, depending on the road conditions.

The upper limit of vehicle speed is set to 80 km/h, etc., and the vehicle normally travels at this speed limit, so if the speed limit changes, the vehicle speed must be changed. However, if the vehicle speed is changed and a new vehicle speed is stored, the previously stored vehicle speed data will be erased, so the vehicle speed change operation must be performed once again to return to the original vehicle speed.

Changing the vehicle speed is quite a tedious process, as it involves operating the accelerator, brake, etc. with one foot, looking at the speedometer, and pressing a memory switch when the predetermined speed is reached.

The first objective of the present invention is to minimize the number of times the driver performs vehicle speed setting operations, and the present invention provides vehicle speed control that allows the vehicle speed setting to be easily changed without memory operations even when road conditions change frequently. A second object is to provide a device, and a third object is to provide a vehicle speed control device that allows easy vehicle speed storage operation.

In order to achieve the above object, the present invention provides a memory data protection means for protecting the vehicle speed data so that the data is not destroyed even if the power is turned off due to -4= stopping of the vehicle or the like. According to this, the memorized vehicle speed is 1
For drivers who only need one vehicle speed,
Once the memory operation is performed, there is no need to perform the memory operation again.

In one preferred embodiment of the present invention, a plurality of vehicle speed memories are provided, and one of the vehicle speed memories is selected depending on the type of switch, the state in which the switch is pressed, for example, the number of times the switch is pressed, etc. In this case, the vehicle speed is stored in the vehicle speed memory, and in the case of a resume switch, the vehicle speed is controlled according to the data read from the vehicle speed memory. According to this, even if the road speed limit changes frequently, the vehicle speed can be changed with a simple switch operation.
Furthermore, the memory operation only needs to be performed once for each vehicle speed.

When setting the vehicle speed, it is cumbersome to operate a switch with your hand while operating the accelerator, brake, etc. with your foot.

Therefore, in one preferred embodiment of the present invention, when the set switch and the resume switch reach a predetermined state, the vehicle speed is increased or decreased while that state is maintained. According to this, the driver can easily change the vehicle speed and store the vehicle speed with only his hands without using his feet.

An embodiment of the present invention will be described below with reference to one drawing.

FIG. 1 shows an electric circuit of a vehicle speed control device according to an embodiment.

This will be explained with reference to FIG. In this example, the electronic control unit 10 is mainly composed of a CMOS type single-chip microcomputer C'PU. CPU
The runaway detection circuit 20 is connected to the reset port RESET, and the external interrupt input port IRQ and the input port 2. 3. KO and NI1 have interface circuits IFI, IF2. IF3. IF4 and I
Via F5, the vehicle speed detection reed switch SW2. Clutch switch SW3. A stop switch SW4 is connected to a set switch SW5 and a resume switch SW6.

A permanent magnet connected to a speedometer cable (not shown) is arranged near the vehicle speed detection reed switch SW2, and when the vehicle moves and the permanent magnet rotates, the contacts of SW2 open and close accordingly. When the contact of SW2 changes from closed to open, the output level of the interface circuit IFI becomes low level L, and the microcomputer CPU
An interrupt request is made.

Clutch switch SW3 opens and closes in conjunction with the vehicle's clutch pedal, and stop switch SW4 opens and closes in conjunction with the vehicle's brake pedal. Stop switch SW4
A stop lamp is connected to , and when SW4 is turned on (
(closed), the stop lamp lights up.

Set switch SW5 and resume switch SW6
is a push button switch, which is placed on the instrument panel at a position that is easy for the driver to operate.

Microcomputer CPU output port O.

is connected to the runaway detection circuit 20, and output ports 02 and 03 are connected to drivers DVI and D, respectively.
Connect V2. A control solenoid SL1 for controlling a negative pressure actuator, which will be described later, is connected to the output of the driver DVI, and a release solenoid SL2 is connected to the output of the driver D V 2.

Control solenoid SL1. Voltage from the vehicle battery is applied to the release solenoid SL2 and the constant voltage power supply circuit 30 that generates the constant voltage Vcc via the power switch SWO and the ignition key switch SWI. The circuit 40 controls the CPU when the brake is applied.
This is to energize the release solenoid SL2 separately from the operation of .

A standby voltage generation circuit 50 is connected to the standby port 5TBY of the CPU. The standby voltage generation circuit 50 includes a power switch SWO and an ignition switch SW1.
When the resistor RA is on, the potential Vb at one end of the resistor RA is equal to the potential Va at the one end of the resistor RB, and the transistor QA is turned off, so the output voltage Vc becomes zero, and the power switch SWO or the ignition When the switch Swl is turned off, the potential V
As a becomes lower, the base potential of the transistor QA becomes lower and QA is turned on, and the voltage from the battery is applied to the constant voltage circuit Z1, so a predetermined voltage (approximately 3V in this example) Vc appears at the output terminal of zl. . When SwO or SWI turns off, the power supply terminal VC of the microcomputer CPU
Although the voltage applied to C becomes zero (after the charge of the capacitor connected to the output of the power supply circuit 3o, etc. is discharged),
This CPU is a CMOS type, and when a voltage of about 3V is applied to the 5TBY terminal, data in the memory is retained. Moreover, the voltage of VCC becomes zero and STB'Y becomes 3.
When a voltage on the order of V is applied, the current consumption of the CPU becomes very small, so even if the vehicle engine is stopped for a long time, there is no fear that the vehicle battery will run out of charge.

FIG. 2 shows the configuration of the negative pressure actuator 100 controlled by the electric circuit shown in FIG. 1. This will be explained with reference to FIG. The housing 101 consists of two parts 101a and 101b. Diaphragm 102 has two parts 101
It is held between the flange portions a and 101b. A space surrounded by the diaphragm 102 and the housing 101a is a negative pressure chamber, and a space surrounded by the diaphragm 102 and the housing 101b is a negative pressure chamber.
The space surrounded by is in communication with the atmosphere. A compression coil spring 103 is inserted between the housing 101a and the diaphragm 102, and pushes the diaphragm 102 back to the imaginary line position when the pressure in the negative pressure chamber is close to atmospheric pressure. A protrusion 104 fixed near the center of the diaphragm 102 is connected to a link of a throttle valve 105. The housing 101a is provided with a negative pressure intake port 107 communicating with the intake manifold 106 and atmospheric intake ports 108 and 109.

110 is a negative pressure control valve, and 111 is a negative pressure release valve, both of which are fixed to the housing 101a. The movable piece 112 of the negative pressure control valve 110 is tiltable about P as a fulcrum, and has one end connected to a tension coil spring 113, and the other end facing the control solenoid SL1. Both ends of the movable piece l12 function as valve bodies, and they open the negative pressure intake port 107, close the atmospheric air intake port 108 (the state shown in the figure), or close the negative pressure intake port 107 in response to energization/deenergization of the solenoid SL1. , the air intake port 108 is opened.

Like the negative pressure release valve ill 110, it has a movable piece 114.degree. tension coil spring +15 and a solenoid SL2, but the movable piece 11.4 closes (in the illustrated state) or opens the atmospheric intake port 109. Note that 116 is an accelerator pedal, and 117 is a tension coil spring.

Figures 3a, 3b, 3c, 3d and 3e
The figure schematically shows the operation of the microcomputer CPU shown in FIG. The operation of the CPU will be explained step by step with reference to each episode. When the vehicle is moving, the reed switch SW2 is constantly turned on and off, and each time the reed switch SW2 is turned off, the microcomputer CPU executes the external interrupt 11-processing shown in FIG. 3d.

First, when the power is turned on, initial settings are performed. That is, the output port is set to the initial level and the contents of the memory are cleared.

Inverts the level of output port 00. That is, if this port Oo is set to a high level H, then its level is set to a low level L, and if it is set to a low level L, it is set to a high level H. This process is always executed at least once within a predetermined period of time if the CPU is operating normally, and as a result, a pulse signal with a substantially constant period is applied to the runaway detection circuit 20 from the CPU. . When the pulse signal is applied, the runaway detection circuit 20 sets the output level of the comparator CP to H, turns on the transistor Q1, and sets the RESET terminal of the CPU to the high level H.

However, the CPU went out of control and the port was closed.

When the pulse is no longer generated, the output level of the comparator CP is inverted to L, turning off the transistor Q1 and applying a low level L to the reset terminal RESET of the CPU. When the reset terminal RESE becomes L, the CPU performs the same operation as when the power is turned on, so the runaway stops.

If the operation is proceeding normally, the CPU is on the input port K.
O, Kl, 2. It reads level 3, etc., determines the operation of the switches as follows, and performs processing according to the determined switch.

If there is no change in the input (unless a timer, flag, etc. is set), step 52-83-5
4-842-843, executes the multiple storage routine of FIG. 3c, and then executes a processing loop that returns to step S2 again. In this case, the contents of the vehicle speed memory, target value register, flag, etc. do not change.

Clutch switch SW3 or stop switch SW4 is on, or the vehicle speed is below a predetermined value (for example, 30 km/h)
below), the level of the output port is set in the direction in which the solenoid is not energized, and the contents of the target value register RO are cleared in order to cancel constant speed control. Also clear all flags. As a result, if the constant speed driving mode is set, it is canceled. Further, the release solenoid SL2 is activated for a predetermined time so that the negative pressure actuator 100 quickly operates in the direction of closing the throttle valve.
energize. The process then proceeds to steps 542-843, passes through the multiple storage routine, and returns to step S2.

When the set switch SW5 is turned on, the process proceeds to step 89-817-318-819 for the first time, sets the set-on flag 5ET-ON to 11''', and sets the control solenoid control duty to 5%.Control solenoid control duty At 5%, negative pressure control valve 1
Since the proportion of time during which the inside of the negative pressure actuator 100 is communicated with the atmosphere increases, the negative pressure actuator 110
moves in the direction of closing the throttle valve, and the vehicle speed decreases over time. Actual control solenoid drive is performed in step S43 according to the set duty. When the set switch SW5 is pressed, the process proceeds to steps S61-862-881... and exits the multiple storage routine, and steps 82-83...59-3 ]7
Proceed to -361.

When the set switch SW5 is turned off, step 59-
8]O-811-812-813-8], proceed to 4, clear the set-on flag 5ET-ON (to 0),
Set the set-off flag 5ET-OFF to 1. Next, the process proceeds to step 361, where the setoff flag 5ET-
OFF is 1, so 567-868-869-870-3
81... and the counter that specifies the vehicle speed memory (
(pointer) Increments the contents of RA (but does not exceed 3), clears and starts the 1-second timer for setting. When this process is finished, the setoff flag 5E
T-OFF is cleared to '0'', i.e. S67
, S68, 869, and S70 are executed only at the first processing timing when the set switch SW5 is turned off. From next time, step 561
-862-863... and so on.

If the set switch SW5 is not turned on even after 1 second has passed since it was turned off, a time over is detected in step S615-3, and the 564-365-866
and proceed. As a result, the contents of the target value register RO are stored in the vehicle speed memory indicated by the contents of the counter RA, and after a throttle initialization routine to be described later is executed, the operation mode is set to constant speed control mode.

Since the target value register RO stores the vehicle speed at the moment when step S14 is executed, that is, the set switch SW5 is turned off, the vehicle speed at that time is stored in a predetermined memory. For example, if the set switch SW5 is turned on and off twice before the set switch SW5 finally turns off (off for 1 second), the processing steps 567-868-869-870 are executed twice during that time. Since this is executed, the content of the counter RA is 2, and the content of the target value register RO is stored in 2 of the vehicle speed memory.

In this embodiment, since there are three vehicle speed memories, step S67 is provided to prevent the value of RA from exceeding three. Therefore, even if the set switch SW5 is turned on and off three or more times in succession, 16-vehicle speed memory 3 is selected.

When the constant speed control mode is entered, steps 540-841-8
42, and each time this process is executed, the target value register R is
The control solenoid control duty is reset so that the contents of O, that is, the memory delivery and the current vehicle speed are equal. If you keep the set switch SW5 pressed,
Since the control duty is set to 5% in step S19, the vehicle speed gradually decreases.

When the resume switch SW6 is turned on, the initial value is 53.
Proceed to 1-844-845-846-847-343,
Resume-on flag RESUME-ON II I
II, clear and start the 0.9 second timer for resume. Next, S61...581-88
2-82 and the subsequent processing loop are executed. Resume switch SW6 is pressed continuously for 0.9 seconds (on)
, a time-over is detected in step 847;
Proceeding to 848, the control solenoid control duty is set to 90%. When the control solenoid control duty is 90%, the proportion of time during which the negative pressure control valve 11o communicates the inside of the negative pressure actuator 100 with the negative pressure source (intake manifold) increases, so that the negative pressure actuator 1 ], O is the throttle valve as time passes. The vehicle moves in the direction of opening and the vehicle speed increases.

When the resume switch SW6 is turned off, first step S31-832-333-834. -835-836
...and the resume-on flag RESUME-
Clear ON to 71 Q II and set the resume off flag RESUME-OFF to rr 1''. If the on time of resume switch SW6 is long and 0.
536-837 if the 9 second timer has expired.
-838-839, the current vehicle speed is stored in the target value register RO, and the contents of the target value register are stored in the vehicle speed memory indicated by the contents of RO, as in the case of turning on/off the set switch SW5. Also, the resume off flag RESUME-OFF is cleared to uOrr so that normal resume operation is not performed in the multiple storage routine.

If the resume switch SW6 turns off before the 0.9 second timer expires, the resume off flag RE
SUME-OFF is "]-" Tealnote.

Proceed to S81-887-888-889-890, increment the contents of counter RA, and set 1 for resume.
Clear and start the second timer, and clear the resume-off flag RESUME-OFF to II OII. S
The processing step of 81-887-888-389-890 is performed when the resume off flag RESUME-OFF is n.
] u , 71, that is, it is executed once every time the resume switch is turned from on to off. therefore,
The counter RA stores the number of times the resume switch SW6 has been turned from on to off.

When one second passes after the resume switch SW6 is turned off, the one second timer for resume times out, so S81-882-883-884-885-88
6, the contents of the vehicle speed memory 3 are stored in the target value register RO when the vehicle speed memory specified by the contents of the counter RA, for example, the three-turn switch SW6, is turned on/off. Then, a throttle initialization routine 886 is executed to set the constant speed control mode. When the constant speed control mode is entered, the process proceeds to steps 540-841-842-843, and the control solenoid control duty is updated so that the current vehicle speed approaches the contents of the target value register.

The throttle initialization routine will now be described with reference to FIG. 3e. Roughly speaking, this process involves the negative pressure actuator 1
00 to a predetermined position (throttle initial opening position) quickly, anticipatory control (open loop control) is performed. That is, the control solenoid control duty is set to a high value (90%), the time to continue this state is calculated in advance according to the contents of the target value register RO, this is set in a timer, and the timer sets the time. Continue the 90% duty control until it becomes over. When the time is over, set the constant speed control flag 20- to set the constant speed mode.

External interrupt processing will be explained with reference to FIG. 3d. This process is to determine the on/off cycle of the vehicle speed detection reed switch SW2. Every time this process is executed, that is, every time SW2 is turned off, the count value of the internal timer is read, and the timer is cleared and started. Furthermore, if the count value of the timer is greater than or equal to a predetermined value (that is, the vehicle speed is less than or equal to a predetermined value), a low speed flag is set. When the low speed flag is set, the process proceeds from step S8 of the main routine to step 815, where the constant speed control mode is canceled in the same way as when the clutch pedal or brake pedal is operated.

In the above embodiment, a CMOS type microcomputer with low power consumption is used as the microcomputer CPU, and a battery backup circuit for retaining memory data is provided.
An example of a non-volatile memory connected to the CPU and its peripheral circuits is shown in Figure 4, which may be configured to connect a memory that is a combination of (electrically programmable and erasable read-only memory) and static RAM to the outside of the CPU. .

Referring to Figure 4, Z2 is a non-volatile read/write memory.
(X2210 manufactured by Xicor), Z3 is a bus driver (SN74LS245), and 60 is a circuit for preventing erroneous data writing when the power is turned on/off. If a non-volatile memory is used, this memory itself may be used as the vehicle speed memory data storage area, or a separate vehicle speed memory may be provided, and the data is transferred from the non-volatile memory to the vehicle speed memory only immediately after the power is turned on, and the vehicle speed data is stored. Data may be written (data updated) to the nonvolatile memory only when there is a change in the data.

Note that the above-mentioned embodiment is one aspect of the present invention, and the present invention can be practiced even if the configuration and operation of the apparatus are partially changed, for example, as described below.

a) The throttle drive means is not limited to the negative pressure actuator, but may also be replaced by a motor such as a stepping motor.

b) The selection of the vehicle speed memory is not limited to the number of times the switch is activated, but may be determined based on the activation time or a combination of multiple types of times. Alternatively, a large number of switches may be provided and one vehicle speed memory may be assigned to each switch.

C) The electronic control device does not necessarily need to use a microcomputer, but can be constructed from general logic circuits or analog circuits. For example, when configured with analog circuits,
The vehicle speed detection pulse may be passed through an F/V conversion circuit to be converted into a voltage, and the vehicle speed memory may be a sampling and holding circuit using a capacitor and an analog gate circuit.

d) The vehicle speed detection means may be of any type as long as it can provide a frequency output or an analog output according to the vehicle speed.

e) As for the switch, for example, the set switch and resume switch are housed in one case and integrated, and when the top is pressed, the set switch turns on (resume switch off).
The resume switch may be turned on (ceramic switch off) when the lower part is pressed.

23-f) The number of vehicle speed memories can be set arbitrarily as long as the memory capacity allows.

As described above, according to the present invention, even if the power is turned off due to engine stoppage, the stored vehicle speed data is retained, so there is no need to re-memorize the same vehicle speed many times, resulting in good operability. In particular, when a plurality of vehicle speed memories are provided, the vehicle speed can be changed with a simple switch operation, and there is no need to perform a vehicle speed memory operation each time the vehicle speed is changed.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an electric circuit configuration of an embodiment of the present invention. FIG. 2 is a longitudinal sectional view showing a negative pressure actuator controlled by the electric circuit of FIG. Figures 3a, 3b, 3c, 3d and 3e
FIG. 1 is a flowchart showing the general operation of the microcomputer CPU shown in FIG. FIG. 4 is a block diagram of a nonvolatile memory and its peripheral circuits showing another embodiment of the present invention. 10: Electronic control device (electronic control means) 24- 20: A constant detection circuit 30: Stabilized power supply circuit 50: Standby voltage generation circuit (memory data protection means) 100: Negative pressure actuator (throttle drive means) 101: Housing 102 :Diaphragm 103:Compression coil spring 104:Protrusion 105:Throttle valve 106:Intake manifold 107=Negative pressure intake 108.109:Atmospheric intake 1■0:Negative pressure control valve 111;Negative pressure release valve 112.1
14: Movable piece 116: Accelerator pedal 117: Tension coil spring SWI: Ignition key switch SW2: Reed switch (vehicle speed detection means) SW3: Clutch switch SW4 Nistop switch SW5: Set switch (first switch means) SW6
:Resume switch (second switch means) SLl
: Control solenoid SL2: Release solenoid CPU: Microcomputer IFI, IF2. IF3. IF4. IF5: Interface circuit DVI, DV2: Driver CP: Comparator Zl: Constant voltage circuit Z2: Non-volatile memory (memory data protection means) Patent applicant Aisin Seiki Co., Ltd. 27- 282- Foil 2 ■ 1 village 17 type; door L Meo. I Knee〇9 Old! ,'02 Otsu 2-□"i-1 Procedural amendment (voluntary) November 21, 1988 1, Case description 1981 Patent application No. 42827 2, Title of invention Vehicle speed control device 3, amendment Patent applicant 4, agent 103 Telephone (13-864-6052 Address 2-27-6-5 Higashi Nihonbashi, Chuo-ku, Tokyo) Detailed description of the invention in the specification subject to amendment Column and drawing 6, Contents of amendment (1) The part marked as (incorrect) on the next page and line of the description should be marked as (correct) 7. Attached documents

Claims (9)

[Claims] (1) Throttle driving means connected to the throttle valve; at least two switch means; vehicle speed detection means; and memory data protection means for protecting the vehicle speed memory and the contents of the vehicle speed memory from power failure, the first switch means being connected to the throttle valve; In response to the operation of the second switch means, a value corresponding to the output signal of the vehicle speed detection means is stored in the vehicle speed memory, and in response to the operation of the second switch means, the contents of the vehicle speed memory are read out, and the throttle is driven according to the contents. A vehicle speed control device comprising: electronic control means for energizing the means. (2) There are multiple vehicle speed memories, and the electronic control means is the first one.
The vehicle speed memory is selected according to the number of times the switch means and the second switch means are activated within a predetermined time. A vehicle speed control device according to claim (1). (3) When the first switch means operates, the electronic control means stores a value corresponding to the output signal of the vehicle speed detection means in the vehicle speed memory, and applies a throttle drive means according to the vehicle speed corresponding to the stored value. Claim No.
The vehicle speed control device described in item 1). (4) The electronic control means biases the throttle drive means in a direction to reduce the opening degree of the throttle valve when the first switch means is in a predetermined state. Vehicle speed control device. (5) When the second switch means maintains a predetermined state for a predetermined time or more, the electronic control means biases the throttle drive means in a direction to increase the opening degree of the throttle valve while the second switch means maintains the predetermined state for a predetermined time or more. , Claim No. (+)
Vehicle speed control device described in Section 1. (6) When the second switch means maintains a predetermined state for a predetermined time or more, the electronic control means biases the throttle drive means in a direction to increase the opening degree of the throttle valve while the second switch means maintains the predetermined state for a predetermined time or more. Additionally, when the state of the second switch means changes, the vehicle speed at that time is stored in a vehicle speed memory, and the vehicle speed is controlled at that vehicle speed. (7) Claim (1) above, wherein the memory protection means is an auxiliary power supply circuit that generates a memory content holding voltage;
The vehicle speed control device according to item (2), item (3), item (4), item (5), or item (6). (8) The memory protection means is a non-volatile memory. 6) The vehicle speed control device described in item 6). (9) The vehicle speed control device according to claim 1, wherein the throttle drive means is a negative pressure actuator including a negative pressure control valve and a negative pressure control solenoid.