(51) Int. Cl. 3rd
`G 05 D 13/162
`
`(19) Japan Patent Office (JP)
`(11) Patent Application Disclosure
`S58-52708
`(12) Patent Disclosure Publication (A)
`Classification
`Internal Control No.
`(43) Disclosure March 29 S58 (1983)
`7740-5H
`
`Number of inventions 1
`Examination requested Not requested
`
`(Total 6 pages)
`
`(54) SPEED CONTROLLING METHOD
`FOR VEHICLE
`
`(21) Application number: 56-151849
`(22) Date of filing:
`September 24, 1981
`
`(72) Inventor Takahiko MUTO
`c/o NIPPON DENSO CO LTD
`1-1 Showa-cho, Kariya-shi
`
`(72) Inventor Y oshikazu MIZUNO
`c/o NIPPON DENSO CO LTD
`1-1 Showa-cho, Kariya-shi
`(72) Inventor Akira IKUMA
`c/o NIPPON DENSO CO LTD
`1-1 Showa-cho, Kariya-shi
`(71) Applicant NIPPON DENSO CO LTD
`1-1 Showa-cho, Kariya-shi
`(74) Agent Takashi Okabe, Patent Attorney
`
`SPECIFICA TION
`
`1 TITLE OF INVENTION
`SPEED CONTROLLING METHOD FOR VEHICLE
`2 CLAIMS
`A speed controlling method for vehicle which adjusts the position of a speed control element of a vehicle
`according to the actual measurement value indicating the actual vehicle speed and the set value indicating the
`target vehicle speed, said method comprising
`a process decreasing or increasing said set value by specified quantity according to a respective number of
`times of accelerating operation and decelerating operation regardless of set operation and cancel operation,
`a process indicating said set value,
`a process which adjusts the position ofthe speed control element using said set value and actual value from
`when set operation is performed to when cancel operation is performed.
`3 DETAILED DESCRIPTION OF INVENTION
`
`This invention relates to a speed controlling method for vehicle controlling automatically so that the
`vehicle speed such as a passenger car follows the target speed, and especially applies to the cruise
`control system which maintains the vehicle speed at set constant speed.
`
`The cruise control system is useful in freeing the driver from the trouble of frequently performed
`adjustment operation of the accelerator pedal. A control system, having the function of accelerating set speed
`or decelerating set speed, which maintains the cruise control at new speed after change by accelerating or
`decelerating during cruise control in order to take further advantage of this system, is also known.
`As a general example, as shown in Examined Patent Publication (Kokoku) No. S51-24677, the
`configuration is: during when the accelerating switch or the decelerating switch is turned on, while the output
`signal, which forcibly drives speed control element to the accelerating side or decelerating side by acting on
`the output circuit, is generated from the output circuit, the actual vehicle speed signal after accelerati
`
`I IAlSEAl
`DARREN L DEJONG
`NOTARY PUBLIC - STATE OF ILLINOIS
`MY COMMISSION EXPIRES:02l07/16
`
`Subaru of America, Inc., et al.
`Ex. 1004 p. 1
`
`

`

`decelerating is stored newly as the control reference value with the action on the memory circuit with the
`timing of resuming the accelerating switch or the decelerating switch.
`The drawback of this system becomes having to continue to turn on the accelerating switch or the
`decelerating switch at the time of accelerating or decelerating until the actual vehicle speed changes to the
`target value. Because of this, the driver's one arm is being constrained during the vehicle speed change, and
`this is inconvenient when it is necessary to conduct vehicle speed change and other operation at the same time,
`for example, changing lanes or in the case of passing, for example.
`
`- 43-
`
`Subaru of America, Inc., et al.
`Ex. 1004 p. 2
`
`

`

`Kokkai JP S58-52708 (2)
`
`Moreover, the time to turn on the switch required for the actual vehicle speed to change until the target
`value changes significantly each time depending on the traveling burden, for example, road surface inclination
`or vehicle load weight, resulting in a sense of inconvenience during driving.
`Disclosed in another example is the control system of Utility Model Application Publication No. S54-596,
`wherein switching the accelerating switch or the decelerating switch with one touch acts on the memory circuit,
`thereby forcefully increasing or decreasing only a set amount of the electric quantity indicating the target
`vehicle speed.
`According to this system, the advantage is that the system requires only a short time to turn on the switch.
`The present invention is an improvement of this system, and the first purpose of the present invention is to
`increase and decrease the target speed with one touch during speed control and make it possible to transfer the
`vehicle speed, while at the same time to enable to increase and decrease the target speed of speed control to be
`started with one touch even before speed control. The second purpose of the present invention is to make it
`possible to easily conduct the increase and decrease operation by displaying the value of the target speed.
`According to the preferred embodiment of the present invention, the set value indicating the target vehicle
`speed is processed as a digital value in the digital control circuit, especially microcomputer. And by the
`increase and decrease operation conducted by the driver and the increase and decrease operation, the digital set
`value indicating the target vehicle speed is increased and decreased by the specified quantity only for the set
`number of times of the operation. This process is performed regardless of whether it is during the speed
`control or not, and the increased and decreased set value is displayed by the display device. The speed control
`is started by the set operation (start operation) which is going to execute the speed control with the set value as
`the target speed.
`To process the set value as the digital value, in the case of continuing speed control for a long period of
`time, has the advantage that the value does not change because of current leakage. Moreover, the digital value
`is advantageous in the case of using a numeric speed display device.
`In Figure 1 showing the first embodiment of the present invention, (1) is the electrical signal processing
`circuit (controller), and this controller is provided with microcomputer (lA) in which the processing step such
`as input, output, computing, and memory is preset by a computer program, and furthermore, necessary input
`signal is transmitted from the sensor and switch to this microcomputer; in addition, an appropriate transmission
`circuit which transmits output signals to the actuator from the microcomputer is provided.
`The microcomputer, as is well known, is provided with a temporary memory (RAM) other than the
`program memory (ROM), and according to the present invention, part of this temporary memory is used to
`store the digital set value indicating the target speed.
`(2) is an actuator which displaces the position of the throttle valve 7, which is a speed control element of a
`vehicle, by the signal of controller (1), and an electric-pneumatic converter which modulates the pressure in
`the pressure chamber by the switching of magnetic valve according the electrical signal is used. This actuator
`is provided with an electromagnetic-actuated release valve which communicates with the pressure chamber
`and the atmosphere to promptly stop the actuation.
`(3) is the speed vehicle speed sensor which generates the pulse signals synchronizing with the rotation angle
`of axle of the vehicle and (4) is the cancel switch which is linked to the clutch pedal and the brake pedal; here,
`at least the time of operation of one of each pedal is "on" and the time of non-operation of both is referred to as
`"off." (5) is a self-reset start switch provided to conduct set operation in terms of starting the speed control and
`is installed in the cover protector of steering rotating shaft. Similarly with this start switch, a self-reset cancel
`switch can be provided in the vicinity of the start switch to stop the speed control manually and can be used in
`combination with the pedal switch.
`(6) is a control panel and is installed in the vicinity of the steering such as the instrument panel. This control
`panel comprises decelerating (down) switch (6A), accelerating (up) switch (6B), and display device (6C) to
`display the set value as numbers indicating the target speed. Depending on the necessity, said start switch (5)
`or manual cancel switch (4) can be installed in this control panel.
`
`- 44-
`
`Subaru of America, Inc., et al.
`Ex. 1004 p. 3
`
`

`

`Kokkai JP 858-52708 (3)
`
`The controller (1) checks the status of cancel switch (4) and start switch (5) by the execution of the program
`in the microcomputer and determines whether it is under control. If under control, the actual vehicle speed Vs
`is computed as the digital value based on the pulse signal provided from the vehicle speed sensor (3). As this
`actual vehicle speed Vs approximates the set value VM of the target vehicle speed stored in RAM, the
`microcomputer generates the output signal to compute and adjust the displacement magnitude of actuator 2.
`Here, the size of the set value VM
`is increased or decreased by the specified quantity, regardless of
`whether under control or not, by the number of times ofthe operation of down-switch (6A) and up-switch (6B)
`provided on the control panel and is stored again in RAM. The set value VM stored in RAM is output to
`control panel (6) and is displayed there as a decimal number.
`The above operation is implemented by the control program exemplified in Figure 3. Now, if the key switch
`of the vehicle is turned on, the power source is supplied to the electric system of Figure 1, the microcomputer
`(lA) is power-on reset in controller (1), and the process starts from the start step 11 ofthe program.
`First, in the initial set step 11, set the status of internal memory, register, and input/output port at the preset
`status. Here, as the set value VM indicating the target vehicle speed, binary number corresponding to 80 km/H
`is stored in the specified address of RAM. Furthermore, the value of the set value VM is serial transferred to
`the control panel. The control panel, when receiving this, parallel converts in the built-in shift register, and
`furthermore, converts to the light-emitting display signal of 7 segments in the decoder for display in the
`display device 6C.
`Subsequently, the program shifts to the circulation routine of after step 13. In step 13, by the frequency of
`the pulse signal provided from vehicle speed sensor (3), the calculation is as the value Vs indicating the actual
`vehicle speed, which will be stored in RAM. Though not shown in figures, the microcomputer sets the
`interrupt program, activates the interrupt program by synchronizing with the pulse signal from the vehicle
`sensor, stores sequentially the value of clock counter, and by the difference between the pervious memory
`value and the latest memory value, the pulse frequency is calculated.
`In decision steps 14 and 15, the switch signals of up and down switches (6A) and (6B) switch signals from
`the control pane (6) is checked, and that from "off' to become "on" is detected. When up-switch (14) is turned
`on, the set value VM is added only for a set amount C in step 16. This additional value C, for example, is
`prescribed at the value corresponding to 2 kglH. On the other hand, in case the down-switch 15 is turned on,
`the set value VM is subtracted for only the set amount C in step 17.
`In this way, the target set value VM, though the initial value 80 km/H is set at first, is increased and
`reduced by the set amount by the switch operation of the control panelS and the value after change is newly
`stored in RAM. With regards to decision steps 14 and 15, the on timing of the switch is detected, and also, the
`circulation routine is repeated at higher speed than the time interval of ordinary switch operation of human
`being so that the set value VM is increased or decreased by only the number of times of the switch operation of
`human being.
`When the set value VM is changed in steps 16 and 17, immediately a new set value VM is transferred in
`output step 18, and the display of display device (6C) is renewed. Therefore, in control panel (6), the switch
`operation can be conducted while viewing the target vehicle speed displayed by the display device (6C) and
`the latest value can be confirmed.
`
`- 45-
`
`Subaru of America, Inc., et al.
`Ex. 1004 p. 4
`
`

`

`Kokkai JP S58-52708 (4)
`
`This display continues while the key switch is turned on regardless of whether under speed control or not.
`The start and stop of the speed control is decision step 19 and 20, and cancel switch 4 is performed by
`checking the turned on status of start switch 5. The decisions can be made by detecting whether each switch is
`in the status of "on" or not.
`In the program process, flag F is used in order to determine whether under speed control or not, and when it
`is detected that the cancel switch 4 is turned on, the value of flag F is 0 in step 21; on the other hand, when it is
`detected that start switch 5 is turned on, the value of flag F is 1 in step 22. The value of this flag F is set using a
`specified address of RAM and can be read; in the initial set step 12 mentioned previously, it is preset at O.
`Speed control step 24 is conducted after being determined that the value of flag F is constantly 1. In the
`case flag F is 0, speed control stop step 25 is executed.
`In speed control step 24, the displacement magnitude of actuator (2) relating to the actual vehicle speed and
`the target vehicle speed is calculated and the calculation result is output. Moreover, in order to have actuator
`(2) in an operating condition, the output which closes the relief valve is provided to the actuator. The control
`system used here performs advance compensation using the speed change and conducts the calculation process
`of the following equation.
`
`D = G 1 {VM - Vs-G2 (Vs-Vso)}
`
`More specifically, the adjustment magnitude D of actuator predicts the vehicle speed after thousands of several
`hundred ms from the actual vehicle speed value V s and its varying gradients (V s is the latest value and V so is
`the value calculated in advance) and determination is made according to the difference between this predictive
`value and the target value VM. Here, G 1 is gain constant and G2 is advance compensation constant, which are
`determined in advance and set in the program.
`By the repeated execution of speed control step 24, actuator (2) displaces the vehicle speed every minute to
`approximate to the target speed and adjust the opening of throttle valve (7).
`On the other hand, in speed control stop step 25, the output to have the displacement of actuator (2) as 0 is
`generated. Furthermore, the output to release the release valve of the actuator is provided to the actuator. By
`the execution of this stop step, the actuator (2) is released from energization and loses the force acting on
`throttle valve (7). As a result, throttle valve (7) is replaced promptly by the return spring, not shown in the
`Figure, in the direction of deceleration, more specifically, the direction closing the intake passage, and the
`speed control operation is left to the driver.
`To sum up the operation ofthis device, first, the initial value "80kmlH" is displayed on the display device
`6C by turning on the key switch. By turning on up and down switches (6B) and (6A), the set stored value VM
`is added or subtracted by the set amount and the latest value is constantly maintained as the speed request by
`the driver. Every time the set value changes, the display of the display device (6C) is changed and the latest
`target speed is displayed. If start switch 5 is turned on, actuator (2) is displaced by using the set value (the
`latest value) VM which has remained in RAM and the actual vehicle speed is controlled. In this case, the speed
`control transfers toward a new target speed. When the cancel switch 4 is turned on, actuator (2) is de-energized
`and the speed control is stopped.
`The device above can be modified and used in combination with the conventional one-touch stored set
`operation. For example, as shown in the coding (8) in Figure 1, the set switch can be added as the input
`elements of controller (1), and the program shown in Figure 3 responding to this switch operation is added to
`the point X. this set switch is arranged in the vicinity of the steering.
`And then, step 26 of Figure 3 detects the closing operation of set switch 8, and if there is a closing operation,
`stores the actual speed value V s at this time as a set value VM. At this time, it immediately jumps to step 18
`and transfers the set value VM to display device (6C).
`In the embodiments described above, the display indicating to the driver whether it is during the influence
`of speed control or not can be performed. The value of said flag F can be used to indicate whether it is during
`the influence of speed control or not, and depending on the value, the flashing of the display lamp (for example,
`set up on the control panel (6) can be changed.
`
`Subaru of America, Inc., et al.
`Ex. 1004 p. 5
`
`

`

`Also, in speed control step 24, an inconvenience status can be detected and be automatically transferred to
`stop step 25. For example, comparing the actual speed value Vs and set value VM and when the difference is
`larger that the specified value (a different value can be used such as 10 kmJH when the speed is under control,
`and 20 kmlH when reaching step 24 for the first time to control speed), flag F can be set at o.
`
`- 46-
`
`Subaru of America, Inc., et al.
`Ex. 1004 p. 6
`
`

`

`Kokkai JP 858-52708 (5)
`
`Moreover, in order to continue to store the memory of the set value VM, during the off time of the key
`switch, a backup power supply can be provided only to RAM. In addition, only the set value VM can be stored
`in the memory circuit as the outside part of computer (lA) and, for example, a backup power supply can be
`provided to only the memory circuit consisting oflatching circuit. In this way, by having the set value VM
`non-volatile to the off operation ofthe key switch, a temporary stop when the speed is under control occurs,
`which is advantageous in the case of resuming the speed control at the same target speed again afterwards.
`Figure 4 depicts the device which uses an analog hard logic circuit of the present invention.
`In the Figure, the intermittent pulse which the vehicle speed sensor (28) generates is converted to direct
`voltage (V9) with frequency-to-voltage conversion circuits (38) and input into error amplifier (30). Moreover,
`the direct voltage is input into the derivative network (31) and the changed portion of the vehicle speed ~ V3 is
`input into error amplifier (30). As one more input of error amplifier (30), there is preset voltage VM indicating
`the target vehicle speed, and error amplifier (30) responds to the above (8) input and generates control voltage
`Vc. Control voltage Vc is provided to amplifier (32) including the voltage value response-type pulse string
`generator circuit and drives actuator (33) in order to displace throttle (34).
`The part described above is well-known, for example, it is embodied in Japanese Patent Laid-Open No. S60-
`106089.
`In the Figure, (35) is the up-switch and (36) is down-switch and both are self-reset; and the keying signal of
`each switch is input into the pre-settabJe up-down counter (37). In counter (37), code generator (37A) for
`preset (for example, consisting of a pull-up resistor and a switch group )is attached, and by the signal of pulse
`generator (37 B), which generates 1 pulse by the key switch 9 being turned on, the set value is preset at the
`time the key switch is turned on.
`And then, when up down switches 35 and 36 are turned on, the count value increases or decreases in
`counter (37) for only the number of times it occurs.
`Digital output generated by counter (37) is converted to analog voltage in the digital-to-analog conversion
`circuits (38). This analog voltage corresponds to preset voltage VM, which is decreased or increased by the
`operation of up down switches 35 and 36.
`The digital output generated by counter (37) is also input into decoder (39), which decodes in order to drive
`the 7 segments of the light-emitting display device (40).
`At the time of changing the memory voltage VM in the above, the display value of the light-emitting
`display device (40) is also changed. These changes are possible while the circuit power supply is provided by
`the key switch 9 being turned on.
`(41) is a start switch and (42) is a stop switch, and both, which are provided to the set input and the reset
`input ofthe flip-flop (43) respectively, are the self reset type. The set output of flip-flop (44) drives the relay
`(45) by amplifier circuit (44). More specifically, by the closing operation of the start switch (41), flip-flop (43)
`is set and the normally open contact of relay (45) is closed. By this, amplifier (32) and actuator (33) are
`powered and the speed control goes into operation mode. On the other hand, when cancel switch (42) is turned
`on, flip-flop (48) is reset and the speed control is stopped since the actuator part of power feeding is cut off by
`de-energizing of relay (45).
`According to the present invention as described above, excellent results can be obtained in that, regardless
`of whether the speed is under control or not, the value of target speed can be increased or decreased, and in
`addition, along with its display, increase and decrease operation can be easily performed.
`4 BRIEF DESCRIPTION OF FIGURES
`Figure 1 is block line drawing depicting one embodiment of the device implementing the present invention
`methodology; Figure 2 is a flow chart depicting the flow chart of the microcomputer program in Figure 1;
`Figure 3 is a flow chart depicting a modified example of the program; Figure 4 is a block line drawing
`depicting another example of the device implementing the present invention methodology.
`
`- 47-
`
`Subaru of America, Inc., et al.
`Ex. 1004 p. 7
`
`

`

`Kokkai JP S58-52708 (6)
`
`1... Controller, 1 A ... Microcomputer, 2 ... Actuator, 3 ... Vehicle speed sensor, 4 ... Cancel switch, 5 ...
`Start switch for setting operation, 6 ... Operating panel, 6 A ... Down-switch for speed reduction operation, 6
`B ... Up-switch for speed increase operation, 6 C ... Numerical readout, 7 ... Throttle valve, 9 ... Key switch,
`28 ... Vehicle speed sensor, 30 ... Differential amplifier, 33 ... Actuator, 34 ... Throttle valve, 35 '" Up-
`switch, 36 ... Down-switch, 37 ... Pre-settable up/down counter, 38 ... Digital/Analog converter, 40 ...
`Readout, 41 ... Start switch, 42 ... Cancel switch, 43 Flip-flop, 45 ... Relay c
`
`Agent Takashi Okabe, Patent Attorney
`
`Figure 1
`
`f-------~
`:
`7
`I
`
`8 Set switch
`3 Vehicle speed sensor
`4 Cancel switch
`5 Start switch
`1 Controller
`1 A Microcomputer
`2 Actuator
`
`Subaru of America, Inc., et al.
`Ex. 1004 p. 8
`
`

`

`Kokkai JP S58-52708 (6)
`
`Figure 2
`1
`
`11 ... Power ON switch
`12 ... Initial setting
`Vm+-80
`13 ... Vehicle speed input processing V s
`14 ... UPSW
`OFF~ON
`15 ... DOWNSW
`OFF~ON
`
`18 ... VM Output
`19 ... CANSW
`ON
`20 ... STA SW
`ON
`24 ... Speed control
`25 ... Speed. control stop
`
`Subaru of America, Inc., et al.
`Ex. 1004 p. 9
`
`

`

`Kokkai JP S58-52708 (6)
`
`Figure 3
`
`Step 13
`To Step 14
`To Step 18
`26 SET SW ON ~OFF
`
`Figure 4
`
`- 48-
`
`Subaru of America, Inc., et al.
`Ex. 1004 p. 10
`
`