JPH07112786B2 - Fail-safe device for constant-speed traveling device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a fail-safe device for a constant speed traveling device used in a vehicle such as an automobile.

[Conventional technology]

A conventional device of this type is a latch composed of, for example, a D-flip-flop (hereinafter, referred to as D.F.F.) separately from a microcomputer for controlling constant speed (hereinafter referred to as a microcomputer). A means is provided to control ON / OFF of the power supply to the actuator for opening and closing the throttle valve for constant speed traveling according to the output state of the latch means. The latch means is set by a command signal for instructing the start of constant speed traveling and reset by a cancel signal for instructing the end of constant speed traveling. The command signal and the cancel signal are input from the command signal input means and the cancel signal input means provided separately from the microcomputer. If the latch means is set, the actuator is powered on, and if it is reset, it is off. On the other hand, the microcomputer turns ON the actuator when the command signal is input.
When the OFF speed was controlled to adjust the opening of the throttle valve, the vehicle was controlled to run at a constant speed so as to reach the target speed, and the control was terminated when the cancel signal was input.

[Problems to be Solved by the Invention]

Since the conventional fail-safe device for a constant speed traveling device is configured as described above, the output state of the latch means and the control operation state of the microcomputer are not monitored because the microcomputer does not monitor the output state of the latch means. However, when the latch means malfunctions due to external noise or the like, there is a case where they do not match. In this case, the fail-safe double system is impaired, and there is a problem in that the vehicle is not safe to drive.

The present invention has been made to solve the above problems, and a constant speed traveling device that can safely drive a vehicle by monitoring the output state of the latch means and setting the output state of the latch means to the correct state. The purpose is to obtain a fail-safe device for use.

[Means for Solving the Problems]

A fail-safe device for a constant speed traveling device according to the present invention comprises a second latch means for controlling OFF of power supply to an actuator.
Second detecting means for detecting the output state of the second latch means and second latch means until the cancel signal is inputted until the detection signal is inputted.
And a reset means for outputting a reset signal for setting the output state.

A fail-safe device for a constant-speed traveling device according to another invention of the present invention is a detection device for detecting a first output state of a latch device for controlling ON of power supply to an actuator, and a command signal not generated. When the detection signal is received, the reset means is provided for outputting to the actuator a reset signal for setting the latch means for controlling the power OFF to the second output state.

[Work]

The fail-safe device for a constant speed traveling device according to the present invention,
When the latch means does not enter the second output state even when the cancel signal is generated, the reset means continues to output the reset signal until the latch means enters the second output state.

In a fail-safe device for a constant-speed traveling device according to another invention of the present invention, when the latch means is in the first output state and the power to the actuator is turned on, even if the command signal is not generated, the reset means resets the reset signal. A signal is output to put the latch means in the second output state, and the power supply to the actuator is turned off.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings. First
FIG. 1 is a configuration diagram of an electric system of a constant speed traveling device including a failsafe device for a constant speed traveling device according to an embodiment of the present invention.
In FIG. 1, 1 is a speed signal generating means for generating a pulse train signal of a desired frequency according to the traveling speed of the vehicle, and 2 is a command signal input means for generating a command signal for instructing the start of constant speed traveling by an external operation. Reference numeral 3 denotes a cancel signal input means for generating a cancel signal for giving an instruction to cancel the constant speed traveling by an external operation. 4, each input terminal has a cancel signal input means 3 and a microcomputer 15 described later.
Is an OR gate connected to. 5 is a D / F / F whose D input terminal (D terminal) is pulled up by a power source through a pull-up resistor 6 and whose reset terminal (R terminal) is
It is connected to the output terminal of the OR gate 4, its clock input terminal (CL terminal) is connected to the command signal input means 2, and its set terminal (S terminal) is grounded. The normal output terminal (Q terminal) is connected to the base of the transistor 7 whose emitter is grounded. The base of the transistor 9 whose emitter is connected to the DC power supply 8 is connected to the collector of the transistor 7 via the resistor 10. 11,12
Are first and second solenoid valves constituting a drive unit of a well-known negative pressure type actuator (the structure of which is shown in FIG. 2) for driving a throttle valve provided in an intake pipe of an engine for constant speed traveling control. Therefore, each coil 11a, 12a is provided. One end of each of the coils 11a and 12a is commonly connected to the collector of the transistor 9. The other end of the coil 11a is connected to the collector of the transistor 13 whose emitter is grounded, and the other end of the coil 12a is connected to the collector of the transistor 14 whose emitter is grounded. Reference numeral 15 is a microcomputer for performing various controls, and an input circuit 15a for processing an input signal, a third
ROM15 that stores the flow shown in the figure as a program
b, a RAM 15c as a work memory, a CPU 15d for performing various kinds of discrimination and calculation, an output circuit 15e for processing a signal for output, and the like. The input circuit 15a is connected to elements 1 to 3 and inverting output terminals (terminals) of D, F, F5. The output circuit 15e is connected to the 1 input terminal of the OR gate 4 and the bases of the transistors 13 and 14.

In FIG. 2, reference numeral 16 denotes an actuator composed of both solenoid valves 11 and 12 and a diaphragm device 17, which opens and closes a throttle valve 19 provided in an intake pipe 18 of the engine during constant speed traveling. The diaphragm device 17 is connected to the input pipe 11b of the solenoid valve 11 whose output pipe is connected to the engine negative pressure and the output pipe 12 of the solenoid valve 12 whose input pipe is connected to the atmospheric pressure, and the air chamber which communicates with the input pipe 11b and the output pipe 12b. A housing 17b forming a 17a,
A tire diaphragm 17c, a rod 17d that connects the throttle valve 19 and the diaphragm 17c, and a spring 17e that presses the diaphragm 17c from the air chamber 17a side are provided.

Next, the main part of the operation of this embodiment will be described with reference to FIG. When a rising command signal is generated from the command signal input means 2, the signal is input to the CL terminal, D / F / F5.
Is set. By setting D, F, and F5, the Q terminal becomes "H" level, so that the transistor 7 is turned on, and the transistor 9 is turned on by this and the transistor 9 is turned on. Transistor 9
Is turned on, the power source 8 and the coils 11a, 12a are brought into conduction. Therefore, the microcomputer 15 turns on the transistors 13 and 14.
・ By controlling OFF, opening / closing of both solenoid valves 11 and 12 can be controlled for constant speed running. Further, when a cancel signal is generated from the cancel signal input means 3, D / F / F5 which has input this "H" level signal to the R terminal via the OR gate 4 is reset. On the other hand, when the cancel signal is inputted from the cancel signal input means 3, the microcomputer 15 outputs the "H" level reset signal for resetting the D / F / F5, and the D / F / F5
Continues to output until it is judged that the terminal of has been inverted from "L" level to "H" level. In other words, the microcomputer 15
Until the F / F5 terminal output determines that F5 is in the reset state, the "H" level reset signal is continuously output to the D / F / F5 R terminal through the OR gate 4. D
When the Q terminal becomes "L" level by resetting F / F5, the transistor 7 is turned off, and the transistor 9 is also turned off. Power supply 8 by turning off transistor 9
And the coils 11a and 12a are disconnected.

The operation of the well-known negative pressure type actuator shown in FIG. 2 is as shown in the following table, and the detailed description thereof is omitted because it is well known.

Next, the detailed operation of the microcomputer 15 will be described with reference to FIG. When power is supplied from a power source (not shown), the third
The processing of the main routine shown in the figure is started. Step
At 101, the contents of the RAM 15c are cleared and initialization is performed. In step 102, the actual vehicle speed v _s is calculated based on the measurement cycle value of the output pulse of the speed signal generating means 1. In step 103, the output is input from the command signal input means 2, and the terminal output of D / F / F5 is input. Step 10
At 4, the output from the cancel signal input means 3 is input. In step 105, the calculated actual vehicle speed v _s is determined whether or 40km per hour, it is determined whether or not input a cancel signal in step 104 at step 106 if 40km per hour or more, inputs the cancel signal If not, step 10
At 7, the state of the settable flag that indicates whether or not constant speed running can be set is determined. If the settable flag is "0" and it is impossible to set the constant speed traveling, the process proceeds to step 108,
Determine whether the terminal output of D / F / F5 is at "H" level,
If it is at "H" level, D, F, F5 have been reset, so in step 109 a settable flag is set to "1" in the RAM 15c to indicate that constant speed running can be set. If the actual vehicle speed v _s in step 105 is determined to be less than per hour 40 km, if it is determined that there is an input of the cancellation signal in step 106, D · F · F in step 108
If the terminal output of 5 is at "L" level and it is determined that D / F / F5 is in the set state, the process proceeds to step 110, the settable flag is set to "0", and the constant speed is set. A constant speed running flag indicating whether or not the vehicle is running is set to "0". The flag that can be set in step 107 is "1"
If it is determined that the state of the constant speed running flag is determined in step 111. In the case of "0", it is determined in step 112 whether or not a rising command signal is input. If it is input, in step 113 the actual vehicle speed v _s is set as the target speed v _r and R
It is stored in AM15c and the constant speed running flag is set to "1". The constant speed running flag is set to "1" in step 111 above.
When it is determined that the vehicle is traveling at a constant speed in step 112, when it is determined that the command signal is not input in step 112, when step 109 is processed, step 110 is processed, and step 113 is processed. In either case, the process proceeds to step 114. In step 114, the state of the settable flag is determined. If it is "0", in step 115 an "H" level reset signal is output to the R terminal of DF, F5 via the OR gate 4, and "1" is output. If so, in step 116, the reset signal is not output and the “L” level is output. In step 117, the state of the constant speed running flag is determined,
If "0", the process returns to step 102 after waiting for a predetermined time in step 120, and if "1", the process proceeds to step 118. In step 118, the control amount is calculated based on the actual vehicle speed v _s and the target speed v _r, and the calculated result is output to the transistors 13 and 14 in pulses in step 119 to turn the solenoid valves 11 and 12 ON and OFF. Control. After the process of step 119, the process proceeds to step 120, and after the process of step 119, the process returns to step 102 to repeat the above operation.

Next, another embodiment of the present invention will be described below. The configuration of the apparatus is the same as that shown in FIGS. 1 and 2, except that the ROM 15b stores the program of the flow shown in FIG.

Next, the operation of this embodiment will be described with reference to FIG. Although the microcomputer 15 does not input the command signal from the command signal input means 2 during non-constant speed running, the terminal output of DF / F5 changes from "H" level to "L" level and If it is determined that F / F5 has been set,
The "H" level reset signal is output to the R terminals of D, F and F5 via the OR gate 4. As a result, D, F, F5 are reset, and the constant speed traveling set is canceled.

Next, the detailed operation of the microcomputer 15 will be described with reference to FIG. In step 201 initializes, to calculate the actual vehicle speed v _s In step 202, in step 203, receives a signal from the command signal input means 2 and enter the terminal outputs of D · F · F5, step 204, cancellation Signal input means 3
Input the signal from. In step 205, the actual vehicle speed v _s Time 4
If 0 km or more is determined, if 40 km / h or more, step 2
In 06, it is determined whether or not the cancel signal is input. If not input, the state of the settable flag is determined in step 207. If it is "0", the setting is changed to "1" in step 208. To do. If the settable flag is determined to be "1" in step 207, the state of the constant speed traveling flag is determined in step 209. If the flag is "0", the constant speed traveling state is not established, and therefore, a rising command is issued in step 210. It is determined whether or not a signal is input. Step if you have entered
At 211, the actual vehicle speed v _s is set to the target speed v _r and the constant speed running flag is set to "1" to indicate that the vehicle is in the constant speed running state. If it is determined in step 210 that the command signal is not input, it is determined in step 212 whether the D / F / F5 terminal output is at "H" level, and it is at "H" level. If not, it is determined that D / F / F5 is set even though the vehicle is running at non-constant speed.
Proceed to 213. Further, when it is determined in step 205 that the speed is less than 40 km / h or when it is determined in step 206 that the cancel signal is input, the process proceeds to step 213. In step 213, both the settable flag and the constant speed running flag are set to "0". When any of the above steps 208, 211, 213 is processed, when it is determined that the constant speed traveling flag is "1" and the vehicle is in the constant speed traveling state in step 209, and when the terminal output is determined to be the "H" level in step 212. In either case, the process proceeds to step 214. Step 214
Then, the state of the settable flag is discriminated. If it is "0", in step 215 a "H" level reset signal is output to the R terminal of DF, F5 via the OR gate 4, and if it is "1". For example, in step 216, the "L" level is output without outputting the reset signal. Steps 217 to 220 are the same as steps 117 to 120 in FIG. 3 and their explanations are omitted. After waiting for a predetermined time in step 220, the process returns to step 202 to repeat the above operation.

Although a negative pressure type actuator is used as the actuator in each of the above-described embodiments, the actuator can be applied to a motor type actuator composed of a DC motor and an electromagnetic clutch, and the same effect as that of the above-described embodiments is obtained.

〔The invention's effect〕

As described above, according to the present invention, the output state of the latch means for turning ON / OFF the power supply to the actuator is detected according to the first and second output states, and the latch means is set to the second output state. Or the reset signal is output so that when the latch means is in the first output state even though the command signal is not generated, the reset signal is output so as to be in the second output state. Therefore, the fail-safe dual system for constant speed traveling is not impaired, and there is an effect that a highly safe vehicle can be obtained in traveling.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an electric system of a constant speed traveling device including a fail-safe device according to an embodiment of the present invention, FIG. 2 is a configuration diagram showing a relationship between an actuator and a throttle valve according to the embodiment, and FIG. FIG. 4 is a flow chart showing the operation of the microcomputer in FIG. 1, and FIG. 4 is a flow chart showing the operation of the microcomputer according to another embodiment of the present invention. In the figure, 2 ... Command signal input means, 3 ... Cancel signal input means, 4 ... OR gate, 5 ... DF / F, 6
...... Pull-up resistance, 7,9 ...... Transistor, 8 ...... Power supply, 10 is resistance, 11,12 ...... Solenoid valve, 11a, 12a ...... Coil,
16 …… Actuator, 18 …… Intake pipe, 19 …… Throttle valve. The same reference numerals in the drawings indicate the same or corresponding parts.

Claims (2)

[Claims] 1. A command signal input means for generating a command signal for instructing the start of constant speed traveling by an external operation, and a cancel signal input for generating a cancel signal for instructing the end of constant speed traveling by an external operation. Means, a latch means which is brought into a first output state by the command signal and is brought into a second output state by the cancel signal or the reset signal, and a throttle valve provided in an intake pipe of the engine for constant speed traveling control. Switch means for turning on and off the power supply to the actuator which is driven to open and close according to the first and second output states of the latch means, the detecting means for detecting the second output state of the latch means, and the canceling. Constant-speed running equipped with reset means for outputting the reset signal until the detecting means detects the second output state after the signal is input. Fail-safe device for a device. 2. A command signal input means for generating a command signal for instructing the start of constant speed traveling by an external operation, and a cancel signal input for generating a cancel signal for instructing the end of constant speed traveling by an external operation. Means, a latch means which is brought into a first output state by the command signal and is brought into a second output state by the cancel signal or the reset signal, and a throttle valve provided in an intake pipe of the engine for constant speed traveling control. Switch means for turning on and off the power supply to the actuator which is driven to open and close according to the first and second output states of the latch means, the detecting means for detecting the first output state of the latch means, and the command. Resetting means for outputting the reset signal when the detecting means detects the first output state although no signal is generated, For example was the constant speed running device for fail-safe devices.