United States Patent 1191
`Nishikawaet al.
`
`[11] Patent Number:
`[45] Date of Patent:
`
`4,628,317
`Dec. 9, 1986
`
`[54] INTER-VEHICLE DISTANCE CONTROL
`SYSTEM FOR VEHICLES
`
`[56]
`
`References Cited
`U.S. PATENT DOCUMENTS
`
`-
`.
`-
`-
`.
`[75] Inventors‘ ‘nalffosgghnlltazz’tglfkasm
`’
`’
`P
`[73] Assignee: Honda Giken Kogyo Kabushiki
`Kaisha, Tokyo, Japan
`
`[21] Appl. No.: 288,033
`
`[22] Filed:
`
`Jul. 29, 1981
`
`Foreign Application Priority Data
`[30]
`Aug. 4, 1980 [JP]
`Japan .............................. .. 55-106949
`
`[51] Int. Cl.‘ ............. .......... .. G08G 1/16; B60Q l/44;
`B6OT 7/12; GOlS 13/93
`[52] US. Cl. .................................. .. 340/903; 340/ 104;
`180/169; 367/909; 342/71
`[58] Field of Search ......... .. 343/7 VM; 340/903, 104;
`367/909; 180/169
`
`3,778,826 12/1973 Flannery eta]. ............. .. 343/7 VM
`3,786,507 1/1974 111111111. . . . . . .
`. . . .. 343/7 VM
`3,921,749 11/1975 Kawada
`. 343/7 v1v1 x
`3,952,301 4/1976 Sorkin ............................ .. 343/7 VM
`Primary Examiner-T. H. Tubbesing
`Assistant Examiner-Gilberto Barron, Jr.
`Attorney, Agent, or Firm-Irving M. Weiner; Joseph P.
`Carrier; Pamela S. Burt
`[57]
`ABSTRACT
`An inter-vehicle distance control system for a vehicle
`wherein the distance between the vehicle and a preced
`ing object and a relative velocity therebetween are
`detected by a detection system such as a radar system,
`and when this distance has become shorter than a prede
`termined value, a reaction force is imparted to a throt
`tling operation member such as a throttling pedal. The
`vehicle operator is effectively advised of this fact.
`
`11 Claims, 3 Drawing Figures
`
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`MERCEDES
`EXHIBIT 1017
`
`

`
`U.S. Patent
`
`‘ me. 9, 1986
`
`Sheet 1 of2_
`
`4,628,317
`
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`A MERCEDES
`EXHIBIT 1017
`
`MERCEDES
`EXHIBIT 1017
`
`
`

`
`‘ US. Patent ;Dec. 9,.1986 ' “ Sheet20f2
`
`4,628,317 ‘
`
`$16.2] '
`
`HYDRAULIC
`PRESSURE
`
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`
`MERCEDES
`EXHIBIT 1017
`
`

`
`1
`
`INTER-VEHICLE DISTANCE CONTROL SYSTEM
`‘
`FOR VEHICLES
`
`FIELD OF THE INVENTION
`The present invention relates to an inter-vehicle dis
`tance control system for a vehicle for safely maintaining
`the distance between the vehicle and an object such as
`another vehicle travelling ahead thereof, by detecting
`the distance from the object and the relative speed by
`the utilization of electromagnetic waves, ultrasonic
`waves, or the like.
`
`25
`
`4,628,317
`2
`member such as a throttling pedal, thereby advising the
`vehicle operator of this fact.
`It is another object of the present invention to pro
`vide an inter-vehicle distance control system for a vehi
`cle constructed such that when the vehicle has come
`abnormally close to a preceding object, thus giving rise
`to an increased danger, an automatic braking system is
`immediately actuated to mitigate a possible collision for
`minimizing the damage of a potential accident, while in
`principle the driver’s will has priority in response to a
`reaction force generated at a throttling operation mem
`ber such as a throttling pedal.
`It is a further object of the present invention to pro
`vide an inter-vehicle distance control system for a vehi
`cle wherein the detecting capability of a detection sys
`tem such as a radar system for detecting interfering
`objects may be maintained at a high level without the
`need to narrow its detection range, and even if a false
`signal is issued there is assured a smooth driving condi
`tion with priority given to the driver’s will.
`A preferred embodiment of the present invention will
`be described in detail hereinbelow with reference to the
`accompanying drawings.
`BRIEF DESCRIPTION OF THE DRAWINGS
`FIG. 1 is a block diagram of an inter-vehicle distance
`control system according to an embodiment of the pres
`ent invention.
`FIG. 2 shows an example of a throttling control unit.
`FIG. 3 shows another example of a throttling control
`unit.
`
`30
`
`RELEVANT ART
`In recent years, an increased number of vehicles and
`increased driving speeds have been giving rise to a
`correspondingly sharp increase in the number of rear
`end collision accidents, and this problem is now a social
`problem. In an effort to solve this problem there have
`been proposed many automatic control systems for
`vehicles wherein the distance from a preceding vehicle
`and a relative speed are measured at all times by the
`utilization of a radar system and when the measured
`‘ values exceed predetermined levels braking is actuated
`automatically.
`However, such conventional systems involve the
`following problems.
`First, since the radar system merely detects whether
`or not‘ there‘ is an object ahead, it is difficult to judge
`whether the detected object will cause ‘a danger. In the
`event that the detected signal is a false signal, an unnec
`essarily actuated braking may cause a danger of being
`hit from the rear by a succeeding vehicle, and this is not
`desirable from the standpoint of safety.
`Such a false signal may be generated for example
`“ where there isa viaduct or road sign, where rain is
`‘ falling heavily, or where the vehicle is passing a sharp
`‘ valley constituting of an upward slope and a downward
`slope.
`‘ Secondly,:there sometimes occurs the case where the
`‘ braking‘action by the automatic braking system and the
`intended driving‘ of the vehicle operator are different
`from each other. There are three means for avoiding a
`vehicle collision, namely, braking, steering and acceler
`45
`ation. Therefore, even when a vehicle is travelling
`ahead, collision is avoidable by a by-passing operation
`“consisting of steering and acceleration if there is enough
`of an inter-vehicle distance still remaining. In such a
`case, it is unsuitable in the actual driving situation to
`completely‘disregard the driver’s will and have the
`brakingsystem operated only automatically.
`Because of the above-mentioned problems, the con
`ventional systems of such type have not been accept
`able. As to the second problem mentioned above, there
`has been proposed the concept of changing the measur
`ing range with ‘the angle of rotation of the steering
`wheel as a parameter, but such an idea is still incomplete
`‘ technically.
`The present invention effectively solves the above
`problems.
`It is an object of the present invention to provide an
`inter-vehicle distance control system for a vehicle
`wherein ‘the distance from a preceding object and a
`relative, velocity therebetween are detected by a detec
`tion system such as a radar system, and when this dis
`tance has become shorter than a predetermined value, a
`reaction force is imparted to a throttling operation
`
`35
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`50
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`60
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`65
`
`DETAILED DESCRIPTION OF THE
`INVENTION
`In FIG. 1, the reference symbol A designates a detec
`tion system of a vehicle for detecting the distance be
`tween the vehicle and a preceding vehicle and a relative
`speed therebetween and for comparing respective thus
`detected values with predetermined ones; the symbol B
`designates a braking control system of the vehicle com
`prising a braking pedal and a device for automatically
`controlling it; the symbol C designates a throttling con
`trol system comprising a throttling pedal and a device
`for automatically controlling it; and the symbol D des
`ignates a braking lamp disposed on the rear of the vehi
`cle.
`Referring now to the detection system A, there is
`employed a FM-CW radar system, wherein oscillatory
`waves generated at an oscillator 1 are modulated by a
`modulator 2 and output therefrom is divided by a direc
`tional coupler 3 into two groups of waves, one being
`sent through circulator 4 to an antenna 5 from which
`they are radiated as radio waves toward a preceding
`object and the other being sent to a mixer 6. Re?ected
`waves from the object are received by the antenna 5,
`and sent through the circulator 4 to the mixer 6, where
`these waves are mixed with those waves directly trans—
`mitted from the directional coupler 3 to create a signal
`of beat frequency. This beat frequency signal is weak,
`and ampli?ed up to a required voltage level by a video
`ampli?er 7, then this ampli?ed signal is transmitted to a
`frequency counter 8 where the frequency is read-out,
`and this read-out value of beat frequency is provided to
`a signal processing circuit 9.
`In the signal processing circuit 9' there is calculated a _
`distance X between the vehicle and the object and a
`relative velocity V}; therebetween on the basis of the
`beat frequency value, and there is determined a proper
`
`MERCEDES
`EXHIBIT 1017
`
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`30
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`distance X5 from the object at that time by using a ve
`locity signal VS sent from the speedometer in the vehi
`cle and the relative speed VR, according to a predeter
`mined proper distance characteristic function. Then,
`the proper distance X5 is compared with the actual
`distance X, and on the basis of a difference Xs-X the
`following output signals are produced.
`Where the difference Xs-X is larger than a predeter
`mined maximum reference value, a (?rst) signal is gen
`erated through an output line 10, whereby the stop lamp
`D is lit at a luminance proportional to that signal level,
`and at the same time an element 11 in the throttling
`control unit C is operated to urge a throttling pedal 14
`toward its idle position side.
`If the value XyX continues increasing and becomes
`larger than a predetermined intermediate reference
`value notwithstanding the provision of the aforesaid
`throttling action, the signal processing circuit 9 issues
`another (third) signal through an output line 12 with a
`limit switch 15, in order to operate an automatic braking
`element 13 in the braking control system B. However,
`since the limit switch 15 is provided at an intermediate
`point of the output line 12 so as to be turned on or off
`according to the position of the throttling pedal 14, the
`25
`intended signal transmission is not effected except when
`the limit switch 15 is closed.
`Furthermore, when the distance from the object has
`become smaller and reached a predetermined minimum
`reference value presumably indicative of unavoidable
`collision, the signal processing circuit 9 generates still
`another (second) signal through an output line 16
`whereby the automatic braking element 13 is directly
`operated to effect the braking and at the same time a
`throttle retarder 17 is operated to hold the pedal 14 at
`the idle position without fail.
`Referring now to the braking control system B, a
`braking pedal 18 is adapted to rotate about a pivot point
`19 in the vehicle body, and this pivotal motion allows a
`master cylinder 21 to be operated through a push rod
`20. Preferably, between the master cylinder 21 and the
`push rod 20 there is provided a vacuum booster (not
`shown). The braking pedal 18 can be moved to its oper
`ating position not only by a treading force of the opera
`tor but also by the automatic braking element 13 ac“
`cording to what has previously been noted.
`The automatic braking element 13 used in this em
`bodiment is of such a type that a force indicated by an
`arrow 13a is applied to the pedal 18 by means of a hy
`draulic cylinder or the like. In the automatic braking
`element 13, the force for actuating the master cylinder
`21 in response to the signal on the output line 12 and the
`actuating force for the same cylinder in response to the
`signal on the output line 16 are desirably not the same;
`that is, the element 13 may be constructed such that the
`braking force based on the signal on the output line 16
`is stronger than that based on the signal on the output
`line 12.
`If the vacuum booster is included between the master
`cylinder 21 and the push rod 20, the automatic braking
`element 13 may be constructed so as to utilize this
`booster for actuation of the master cylinder. Even in
`this case, as mentioned above, the braking forces caused
`by the output lines 12 and 16 may preferably be made
`different.
`Referring now to the throttling control system C, the
`throttling pedal 14 is mounted so as to be pivotable
`about a pivot point 22 with respect to the vehicle body,
`and when it is moved pivotally in a clockwise direction
`
`4,628,317
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`in FIG. 1 by virtue of a treading force applied at the
`lower end of the pedal 14 by the vehicle operator, a
`butter?y valve (not shown) of a carburetor (not shown)
`is opened through a throttling wire whereby an acceler
`ating force can be exerted on the vehicle. On the other
`hand, when the throttling pedal 14 is returned in the
`opposite direction by a spring 24, an engine braking is
`effected to decelerate the vehicle.
`Engaged with the throttling pedal 14 are: the throt
`tling control element 11 for providing the spring 24
`with a variation of resiliency according to the intensity
`of the signal on the output line 10 from the signal pro
`cessing circuit 9 thereby urging the pedal 14 to its idle
`position side; the foregoing limit switch 15 adapted to
`be closed when the throttling pedal 14 is in its idle posi
`tion; and the retarder 17 for holding the throttlng pedal
`14 in its idle position in response to the signal on the
`output line 16.
`For the retarder 17 there may be used a hydraulic or
`pneumatic cylinder which functions to push the throt
`tling pedal 14 back to the idle position with a minimum
`time lag in response to the signal on the output line 16.
`Regarding the throttling control element 11, a partic
`ular example thereof is shown in FIG. 2, in which the
`element 11 comprises a screw 26 mounted on an output
`shaft of a pulse motor 25, a nut 27 ?tted over the screw
`26, and two rails 28 for preventing the rotation of the
`nut 27. The pulse motor 25 is ?xed to the vehicle body,
`and when it rotates the screw 26 in response to the
`signal on the output line 10, the nut 27 is moved to the
`left in the ?gure, so that a variation of resiliency propor
`tional to the signal can be imparted to the spring 24.
`Referring now to the braking lamp D, there may be
`used an existing braking lamp, provided its luminance is
`not ?xed but rather is variable in proportion to the
`intensity of the signal on the output line 10. The opera
`tion of the above construction is described hereinbelow.
`Even when there is an interfering object such as a
`vehicle ahead, if the object is so far away that the radar
`detection system A does not detect any danger, the
`signal processing circuit 9 provides no signal on any of
`the output lines 10, 12 and 16, so that the vehicle opera
`tion can be performed on the basis of the driver’s judg
`ment only. In such state, the vehicle driver can effect
`the engine braking by releasing his foot from the throt
`tling pedal 14, or he can actuate the brakes any time by
`treading the braking pedal 18.
`When the object approaches and the radar detection
`system A detects the possibility of collision and pro
`vides a signal through the output line 10, the throttling
`control element 11 operates to apply a force to the
`throttling pedal 14 so as to return the latter to its idle
`position. The vehicle driver is warned by feeling the
`weight of the pedal 14 based on the reaction force. At
`the same time, the braking lamp D is lit whereby a
`succeeding vehicle is advised of a possible impending
`actuation of the brakes.
`In the above case, the reaction force transmitted as a
`warning to the vehicle driver through the pedal 14 is
`proportional to the intensity of the signal on the output
`line 10, so the vehicle driver can fully recognize the
`degree of the possibility of collision with the interfering
`object. In case the vehicle driver continues to tread the
`throttle pedal 14 in opposition to the above reaction
`force, there will be no sudden actuation of the brakes
`for the vehicle against the driver’s will, nor will a decel
`erated state occur. Conversely, when the vehicle driver
`anticipated a danger, he may slacken the treading force
`
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`MERCEDES
`EXHIBIT 1017
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`4,628,317
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`6
`on the pedal 14. Particularly, when the vehicle drive is
`lating valve 31 allows the pressurized ?uid from the
`unaware of a preceding object because of looking to the
`hydraulic pressure source 30 to ?ow into a tank 32;
`side while driving or the like, the pedal 14 will be re
`. thereby removing the load on the pump. Basically, the
`turned little by little by virtue of the above reaction
`pressure regulating valve of such a construction may be
`force which opposes the constant treading force of the
`a control valve of a power steering device having a
`vehicle driver, whereby the danger of collision can be
`hydraulic reaction chamber.
`avoided or reduced.
`The throttling pedal 14 is pulled. to its idle position at
`In such a state, if the vehicle driver continues to tread
`all times by means of a known return spring 33. In this
`I the throttle pedal 14in opposition to the increased reac
`embodiment, in place of the retarder 17 in the above
`tion force, the possibility of collision becomes larger
`embodiment, the pressure regulating valve 31 is actu
`and the detection system A intensi?es the signal on the
`ated so as to obtain its maximum pressure with a signal
`output line 10 and at the same time outputs a signal
`on the output line 16 which directs a braking control
`through the output line 12. In this case, because of the
`system B7 to apply a full braking, whereby the same
`limit switch 15 at an intermediate point of the output
`effect is attained. The hydraulic cylinder 29 may be
`line 12, the automatic braking operation based on the
`replaced by a diaphragm type actuator driven with a
`signal on the output line 12 is under the vehicle driver’s
`pneumatic pressure.
`judgment; accordingly, if the driver desires to actuate
`The limit switch 15 in the aforesaid embodiment is
`the brakes and releases his foot from the throttling pedal
`not shown in FIG. 3, but in the ordinary throttling
`14 for treading the braking pedal 18, the limit switch 15
`system the throttle valve and the throttling pedal are
`is closed to start braking immediately. In this case, it is
`positioned in one-to-one relationship, so it is convenient
`possible to save the time required for the vehicle driver
`to mount a limit switch on the pedal side. But in the case
`to move his foot from the throttling pedal 14 onto the
`of a vehicle equipped with an automatic cruise control
`braking pedal‘ 18. On the other hand, as long as the
`device, the limit switch 15 should be affixed to a part
`vehicle driver continues depressing the throttling pedal
`other than the throttling pedal.
`14 against the reaction force, the braking'operation by
`25
`In the above embodiment the detection system A
`the automatic‘braking element 13 is not effected since
`utilizes a radar system, but it will be understood that
`the limit switch 15 is open.
`there may be employed a system which utilizes ultra
`When the throttling pedal 14 is returned to its idle
`sonic waves.
`position before a signal is issued through the output line
`As another example of the braking lamp D there may
`12 and theengine braking is being actuated, if the possi
`be used one wherein the number of times of ?ashing
`bility of collision has increased because a preceding
`thereof varies according to the intensity of a signal on
`vehicle has effected a sudden braking or for some other
`the output line 10, that is, the interval of ?ashing is
`reason and there is issued the signal through the output
`changed, whereby a succeeding vehicle can be advised
`line 12,. the brakes will be actuated automatically since
`of the degree of a possible deceleration.
`the limit switch 15 is already closed. In this case, there
`From the foregoing description it should be readily
`i will arise no problem because the vehicle driver agrees
`clear that the present invention attains the following
`to the. actuation of the brakes.
`effects.
`In case a preceding vehicle suddenly changes its
`Since the invention is constructed such that a reaction
`speed from a cruising speed to a zero speed as in the
`force is produced at a throttling pedal according to the
`case of a multiple vehicle collision on an expressway, or
`degree of a possible danger, the vehicle driver can di
`in case the driver of a preceding vehicle suddenly actu
`rectly feel the degree of the danger, and since the inven
`ates the‘brakes notwithstanding the foregoing operation
`tion is constructed so that the vehicle driver’s will has
`a for deceleration of the vehicle, in question or in case the
`priority over a mechanical judgment except in an emer
`situation suddenly changes contrary to the vehicle driv
`gency, it is possible to overcome problems, e.g., rear
`er’s judgment and it becomes impossible to avoid colli
`end collision, which may be caused by the operation of
`‘ sion, the detection system A issues a signal through the
`a conventional automatic braking system.
`1 output line 16 to allow the retarder 17 to force the
`When the driver’s attention is not directed to the
`throttling pedal 14 back to its idle position, and at the
`front, such as due to inattention or‘ when looking to the
`same time the automatic braking element 13 is operated
`side while driving, the throttling pedal gradually moves
`to apply the brakes fully. In this case, since the pedal 14
`to its idle position against the treading force of the vehi
`is sure to be held in its idle position by the retarder 17,
`cle driver, so that collision can be prevented from oc
`the mass of the driver’s foot due to an inertial forward
`curring.
`acceleration at the time of braking is prevented from
`A manner of driving such as turning a T-shaped cor
`being exerted on the pedal 14 to the extent of moving
`the latter to its accelerating position.
`ner with a guardrail placed ahead while the tires are
`55
`screeching at a certain degree of high speed is not desir
`In FIG. 3 there is shownlanother example of the
`able from the standpoint of traf?c hindrance. In such a
`throttling control system, wherein the same elements
`case, an increased reaction force of the throttling pedal
`are indicated with the same reference numerals. The
`‘numeral 29 designates a hydraulic cylinder, into which
`in accordance with the invention calls on the vehicle
`is supplied a pressurized oil from a hydraulic pressure
`driver to stop such as act.
`60
`An initial signal for detecting an object is varied ac‘
`source 30 through a pressure regulating valve 31. One
`cording to the possibility of collision, and the throttle
`end of a piston rod 29a is connected to the upper end of
`a throttling pedal 14, and when a signal is provided
`closing action with this signal can be controlled by the
`vehicle driver through the throttling pedal, so that it is
`through an output line 10 the opening of the valve 31 is
`adjusted in proportion to the intensity of the signal and
`no longer necessary to fear the occurrence of a false
`65
`signal which has heretofore been a problem and hence it
`the hydraulic pressure is transmitted to a cylinder 29 to
`urge the throttling pedal 14 to itsidle position through
`is not necessary to narrow the detection range of the
`detection unit.
`a rod 29a. In the absence of a signal, the pressure regu
`
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`MERCEDES
`EXHIBIT 1017
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`15
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`20
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`7
`In case of an emergency wherein the possibility of
`collision is very high, the throttling pedal is returned to
`its idle position quickly and independently of the vehi
`cle driver’s will, and the automatic braking device is
`sure to be operated, so that it is possible to promptly
`avoid collision or mitigate collision effectively.
`We claim:
`1. An inter-vehicle distance control system for a vehi
`cle having brake means and throttle means, comprising:
`a control signal generating means for providing a
`control signal output indicative of a possibility of
`collision with an object ahead of the vehicle;
`throttle control means for imparting to a throttle
`pedal a reaction force according to the intensity of
`said control signal output;
`said reaction force being imparted in the direction of
`urging said throttle pedal to the engine-idling posi
`tion thereof;
`brake control means for operating in conjunction
`with said throttle control means in response to said
`control signal output to brake the vehicle automati
`cally if a possibility of collision increases in the
`throttle control means activated condition;
`said control signal output including a ?rst signal pro
`vided when the distance between said vehicle and
`said object drops below a predetermined maximum
`reference value;
`said ?rst signal being fed directly to said throttle
`control means to operate said throttle control
`means;
`said throttle control means including an assembly for
`producing said reaction force according to the
`intensity of said ?rst signal;
`said control signal output includes a second signal
`provided when the distance between said vehicle
`and said object drops below a predetermined mini
`mum reference value; and
`said second signal serving to operate said brake con
`trol means to brake said vehicle regardless of the
`operative condition of said throttle pedal.
`2. A control system according to claim 1, wherein:
`said reaction force producing assembly includes a
`spring engaged with said throttle pedal and means
`for providing said spring with a variation of resil
`iency in dependence upon said ?rst signal.
`3. A control system according to claim 2, wherein:
`said resiliency providing means has a control motor
`for providing a rotational displacement in depen
`dence upon said ?rst signal and means for convert
`ing said rotational displacement into a linear dis
`placement of said spring.
`4. A control system according to claim 1, wherein:
`said reaction force producing assembly includes a
`hydraulic cylinder connected to said throttle pedal
`and valve means for supplying hydraulic ?uid to
`said hydraulic cylinder to apply hydraulic pressure
`in dependence upon said ?rst signal.
`5. A control system according to claim 1, wherein:
`in addition to operating said throttle control means,
`said ?rst signal operates a warning means at the
`rear of said vehicle.
`6. A control system according to claim 5, wherein:
`said warning means is a light which is operated such
`that the intensity of illumination, or rate of ?ashing,
`
`4,628,317
`8
`thereof is dependent upon the strength of said reac
`tion force.
`7. A control system according to claim 1, wherein:
`said control signal output includes a third signal pro
`vided when the distance between said vehicle and
`said object drops below a predetermined interme
`diate reference value, said third signal serving to
`operate said brake control means to brake said
`vehicle if said throttle pedal is in an engine-idling
`condition thereof.
`8. A control system according to claim 7, wherein:
`said third signal is fed to said brake control means via
`a limit switch which is controlled by said throttle
`pedal.
`9. An inter-vehicle distance control system for a vehi
`cle having brake means and throttle means, comprising:
`a control signal generating means for providing a
`control signal output indicative of a possibility of
`collision with an object ahead of the vehicle;
`throttle control means for imparting to a throttle
`pedal a reaction force according to the intensity of
`said control signal output;
`said reaction force being imparted in the direction of
`urging said throttle pedal to the engine-idling posi
`tion thereof;
`brake control means for operating in conjunction
`with said throttle control means in response to said
`control signal output to brake the vehicle automati
`cally according to the intensity of said control
`signal output;
`said control signal output including a ?rst signal pro
`vided when the distance between said vehicle and
`said object drops below a predetermined maximum
`reference value;
`said ?rst signal being fed directly to said throttle
`control means to operate said throttle control
`means;
`said throttle control means including an assembly for
`producing said reaction force according to the
`intensity of said ?rst signal;
`said control signal output includes a second signal
`provided when the distance between said vehicle
`and said object drops below a predetermined mini
`mum reference value, said second signal serving to
`operate said brake control means to brake said
`vehicle regardless of the operative condition of
`said throttle pedal; and
`said control signal output including a third signal
`provided when the distance between said vehicle
`and said object drops below a predetermined inter
`mediate reference value, said third signal serving to
`operate said brake control means to brake said
`vehicle if said throttle pedal is in an engine-idling
`condition thereof.
`10. A control system according to claim 1, wherein:
`said second signal is fed directly to said brake control
`means.
`11. A control system according to claim 1, wherein:
`said brake control means includes an automatic brak
`ing device operable by said second or said third
`signals; and
`said braking device operably cooperates with said
`second and third signals such that the braking force
`initiated by said second signal is greater than that
`initiated by said third signal.
`
`35
`
`65
`
`i
`
`MERCEDES
`EXHIBIT 1017