automatic_gear_changer

8/7/2019 automatic_gear_changer

1/12

United States Patent [19]Sato et al.

[11] Patent Number:

[45] Date of Patent:4,884,201

Nov. 28, 1989

[54] AUTOMATIC GEAR CHANGE DEVICE

[75] Inventors: Yuji Sato; Hiromi Kono; AkifumiTanoue; Yoshiyuki Kimura, all ofHigashi-matsuyama, Japan

[73] Assignee: Diesel Kiki Co., Ltd., Tokyo, Japan

[21] Appl. No.: 206,865

[22] Filed: Jun. 13, 1988

[30] Foreign Application Priority Data

Jun. 12, 1987 [JP] Japan 62-146725

[51] Int. CI.4 B60K 41/18; G05B 9/02[52] U.S. CI 364/424.1; 74/866;

364/431.11[58] Field of Search 364/424.1, 431.11;

74/866; 192/0.052,0.092

[56] References Cited

U.S. PATENT DOC~ENTS

4,324,322 4/1982 Sibeud 192/0.0924,361,060 11/1982 Smyth 192/0.0924,531,190 7/1985 Drews et al. 364/431.114,532,594 7/1985 Hosaka et al................. 364/431.114,558,416 12/1985 Pauwels et al 364/431.114,638,690 111987 Hattori et al 74/866

4,662,494 5/1987 Wakiya et al 192/0.0524,677,880, 7/1987 Hattori et al 192/0.052

4,698,763 10/1987 Smyth 364/424.14,722,248 2/1988 Braun 74/8664,765,450 8/1988 Kurihara et al 192/0.092

Primary Examiner-Parshotam S. LallAssistant Examiner-Christopher L. MakayAttorney, Agent, or Firm- Wenderoth, Lind & Ponack

[57] ABSTRACT

An automatic gear change device includes a first actua-tor operation control circuit for controlling the opera-tion of a . first actuator, a second actuator operationcontrol circuit forcontrolling the operation of a secondactuator, and a main control circuit for controlling theoperation of the first and second actuator operationcontrol circuits. The device further includes a commu-nication line interconnecting the first and second actua-tor operation control circuits to thereby enable datatransmission/reception between each operation controlcircuit and the main control circuit through the otheractuator operation control circuit and the communica-tion line.

5 Claims, 6 Drawing Sheets

I 4 3

I~ERNAL E ? 2COMBUSTION t-.. CLUTCH .. TRANSMISSION 9 JENGINE7

5 ,OPERATION

CONTROL1ST _ _ j

ICIRCUITFOR 1ST

ACTUATOR

ACTUATOR

I17

129

10

I18

OPERATION

CONTROLCIRCUIT

2ND . .__j

FOR 2NDACTUATOR

13 ACTUATOR 6

"


2/12

u . s . Patent Nov. 28,1989

(\JT

- _

(!)

u,

zo(J)

(J)

~(J)

Z


3/12

u . s . Patent Noy.28, 1989 Sheet 2 of 6

~--

w a : : :""=~O~ 0 C f )o a : : : za : : : I - Wl L . C f ) C f ) N

o

LL

4,884,201

0o : ; tC \J

: : :>a .o

.Q

~ ..~

O'l

I"-./

.Q0C \J roC \J a : : : r oW

00 I -U

~ zZW C f ) : : >

0 0 0ro 0ro 0 , , ro fC)c o \C \J

,\\ ,

I -o~~--

:, ~z ,,

L _~~ J

O 'l .'C \ J /

I -z _ r zwO < t o< ! > f - : c : : t : : > f - < {0: : C f ) ~ 1 - C f ) 1 -< t 0 < t u o < tI - a . 0 < t a . o

a : : :W 0

_ r ~ID _ r< tz: : >a : : :. . . . .< ! >...........w> < ! > a : : :

,0,-C \J

eo~

eO' l- r- . .. . .. . .. . .,

a : : :WoooWo

.Q ,

C \ J '

L__---+

a : : :WoooWo

.Q

C \JC \ J , .. .- - '- - .. .. ,

a : : :WooozW

.Q

oro


4/12

u . s . Patent Nov. 28,1 989 Sheet 3 o f 6 4,884,201F I G . 3

~-------T---------

WillW ill,IIII

\

\

D/U-C/ U Will l l iW

TIME

C/U: MAIN CONTROL CIRCUIT

D/U: OPERATION CONTROL CIRCUIT FOR 1ST OR2ND ACTUATOR

F I G . 6

TRANSMISSION RECEPTIONTASK FORCOMMUNICATION CABLE

168

ACTUALPOSITION 174DATATRANSMISSION

~176


5/12

u . s . Patent Nov. 28, 1989

FIG.4 (0)

TARGETPOSITION 104DATATRANSMISSION

RECEPTION BACK UPFLAG RESET PROCESSING

100

NO

Sheet 4 of 6

FIG.4 (b)

1 1 2

RECEPTIONFLAG SET ~114

RECEPTIONDATA =ERRORCODE?

RECEPTION ERROR CODEDATA SAVESAVE

110

4,884,201

108 120

RETURN 122


6/12

u . s .Patent No v. 28, 1989 Sheet 5 of 6 4,884,201FIG 5. (a)

TRANSMISSION/RECEPTION 130TASK

NO

138

ERROR CODESAVE

RECEPTIONDATA SAVE

BACK-UPPROCESSINGINDICATIONDATATRANSMISSION

140

ACTUALPOSITIONDATATRANSMISSION

~144

TRANSMISSIONTO OTHER D iu

162

RECEPTIONFROMOTHER C/

U

164

TRANSMISSIONTO C/ U


7/12

u . s . Patent Nov. 28, 1989

FIG s.u

146

BACK-UP 150FLAG SET

ERROR CODETRANSMISSIONINDICATIVEOF ERROR INCOMMUNICATIONLINE FROMC/

UTO D/U

156

Sheet 6 of 6

154

RECEPTIONFLAG RESET

4,884,201


8/12

14,884,201

AUTOMATIC GEAR CHANGE DEVICE

BACKGROUND OF THE INVENTION

1. Field of the Invention:

The present invention relates to an automatic gearchange device for controlling the operation of a geartransmission and a clutch in an automotive vehicle.2. Description of the Prior Art: 10One example of automatic gear change devices of the

type described is disclosed in Japanese patent laid-openpublication No. 61-192954 in which two actuators formanipulating a clutch and a gear transmission are con-trolled based on the control signals issued from a single 15control unit. The control unit is mainly composed of amicroprocessor operable to determine the control sig-nals based on input signals representing various travel-ling condition data including the vehicle speed.The disclosed device is disadvantageous, however, in 20

that the control unit and the actuators have a low com-patibility -with the corresponding components in anautomobile of a different type.With this difficulty in view, a somewhat successful

device has been proposed in Japanese patent application 25No. 61-154339 filed by the present assignee. The pro-posed device includes an actuator operation controlunit which takes over a portion of the function of theconventional main control unit, and a main control unitfor controll ing the actuator operation control unit, the 30actuator operation control unit being disposed adjacentto each actuator for controlling the operation of thelatter.The foregoing device is still unsatisfactory, however,

in that since the actuator operation control units are 35connected to the main control unit by exclusive con-necting lines, they are likely to runaway when the ex-clusive connecting lines are damaged or broken away.

SUMMARY OF THE INVENTION

With the foregoing drawbacks in view, it is an objectof the present invention to provide an automatic gearchange device which has a safe and reliable operation.To achieve this object, there isprovided according to 45

the present invention an automatic gear change device,comprising:a gear transmission for transmitting the rotary motion

of a driving shaft to a drive shaft while allowing thespeed of rotation of the driving shaft to be changed 50through a plurality of speed ranges;a clutch for connecting and disconnecting said driv-

ing shaft and said gear transmission for transimitt ing atorque of said driving shaft to said gear transmission;a first actuator responsive to a first external signal for 55

operating said clutch;a second actuator responsive to a second external

signal for operating said gear transmission;first actuator operation control means for controlling

the operation of said first actuator; 60second actuator operation control means for control-

ling the operation of said second actuator;main control means for controlling said first and sec-

ond actuator operation control means; andcommunication means electrically interconnecting 65

said first actuator operation control means and saidsecond actuator operation control means for permittingelectric signals to be transmitted through said communi-

2cation means between said first and second actuatoroperation control means.With this construction, when a communication line

extending between the main control means and the first5 actuator operation control means is damaged or out of

order, the first actuator operation control unit isbrought into communication with the main controlmeans through the second actuator operation controlmeans held in communication with the main controlmeans and the communication means extending be-tween the second actuator operation control means andthe first actuator operation control means. Thus, signaltransmission/reception between the first actuator oper-ation control means and the main control means is stillpossible. Alternatively, when an exclusive communica-tion line extending between the main control means andthe second actuator operation control means is dam-aged or out of order, the second actuator operationcontrol means is brought into communication with themain control means via the first actuator operationcontrol means and the communication means.Many other advantages and features of the present

invention will become manifest to those versed in theart upon making reference to the detailed descriptionand the accompanying sheets of drawings in which apreferred structural embodiment incorporating theprinciples of the present invention is shown by way ofillustrative example. 'FIG. 1 is a block diagram showing the general con-

struction of an automatic speed change device accord-ing to the present invention;FIG. 2 isa schematic block diagram of a first actuator

operation control circuit incorporated in the automaticgear change device shown in FIG. 1;

FIG. 3 is a time chart illustrative of data transmis-sion/reception timing between a main control circuitand the first actuator operation control circuit or be-tween the main control circuit and[a second actuatoroperation control circuit;FIG. 4(a) is a flowchart illustrative of a manner in

which data transmission is controlled in the main con-trol circuit;FIG. 4(b) is a flowchart illustrative of a manner in

which data reception is controlled in the main controlcircuit;FIGS. 5(a) and 5(b) are flowcharts il lustrative of a

manner in which data transmission/reception is con-trolled in the first actuator operation control circuit or

in the second actuator operation control circuit; andFIG. 6, appearing with FIG. 3, is a flowchart show-ing a manner in which data transmission/receptionachieved in the first actuator operation control circuitand the second actuator operation control circuitthrough a communication cable is controlled.

40

DETAILED DESCRIPTION

A preferred embodiment of the present invention willbe described hereinbelow in detail with reference to theaccompanying drawings.FIG. 1 shows the general construction of an auto-

matic speed change device embodying the present in-vention. The device includes an internal combustionengine 1, a gear transmission 3 connected with a driveshaft 2 of a motor vehicle, and a clutch 4 connecting' anddisconnecting the gear transmission 3 and a drivingshaft of the internal combustion engine 1. The clutch 4and the gear transmission 3 are drivingly connectedwith first and second actuators 5, 6, respectively. The


9/12

34,884,201

4first and second actuators 5,6 are operative in response The first actuation operation control circuit 7 in-to electric signals delivered from first and second actua- eludes a decoder 19a for receiving target position datator operation control circuits 7, 8, respectively, The for the clutch 4 delivered from the main control circuitactuators 5, 6 comprise fluid-pressure actuators each 13 and converting the thus inputted data into corre-composed of a fluid-pressure cylinder, a solenoid- 5 sponding voltage signals, The output signals of the de-operated valve and the like (not shown). coder 19a are delivered to a subtractor 20a where they

Each of the first and second actuator operation con- are subtracted with the signal generated by the firsttrol circuits 7, 8 is mainly composed of a microproces- stroke sensor 9. The output signal from the subtractorsor and is constructed such that it produces a control 20a isthen inputted to a variable gain regulator 21a. Thesignal required for controlling the clutch or the gear 10 signal generated by the first stroke sensor 9 is also sup-transmission 3 based on data received from a main con- plied to an encoder 22a which in tum converts thetrol circuit 13 (described later in detail) and delivers the signal into a predetermined digital code signal. Thecontrol signal to the first actuator 5 or the second actua- digital code signal is thereafter transmitted to the maintor.6 to thereby control the operation of the clutch 5 or control circuit 13 as actual position data.the gear transmission 3: 15 The variable gain regulator 21a serves to regulate theThere are provided three stroke sensors 9, 10 and 11. input signal into a desired signal level required for oper-

The first stroke sensor 9 serves to detect the stroke of a ation o.f the first actuato~ 5 and supply the thus. reg?-. , th 5 lated SIgnal to a pulse-WIdth modulator 23a which In

non-illustrated. operanon member of e first actuator . he signal ived i t di 'tal' 1 t' . tum converts t e SI receive In 0 a 181 SIgna 0The second ~d third stroke sensors ~O, 11 serve to 20 be suppled to the first actuator 5 while regulating thedetect, respectively, the stroke of a non-illustrated oper- ul idth f th di 'tal . al th b hi'. 6 ble i P se-wr 0 e 181 SIgn ere y ac evmg aation ~em~r o~ the second actuator mova e ~ a duty factor control of the first actuator 5,gear-shift direction and the stroke of the ,operatIon A central processing unit (CPU) 24 a is composed of amember, of ~e second actuat~r 6 movable In a gear- microprocessor of a per se known construction andselect ~rrectIo~. The output SIgnal of the ~rrst stroke 25 serves to control the data transmission/reception tim-s~nso~ISsup~hed to the first actuator operation cont~ol ing, error processing and the like.circuit 7 while the outputs ?f the second and third The second actuator operation control circuit 8 isstroke ,sensors 10, 11,are.supplied to the second actuator substantially the same in construction as the first actua-operatI~>ncontrol crrc.wt 8 so that a feedback control tor operation control circuit 7 except that it is providedsystem IS completed Wl~hrespect to ~ach.of the first and 30 with two sets of the aforesaid components, other thansecond actuator operation ~ontrol crrcu~ts 7? 8. the CPU 24a, since the second actuator 6 is composed. The first actuator op:ratlon contrOl.crr~uIt 7 and the of a gear shift actuator member and a gear select actua-second actuator operation cont~ol ,crrcUlt 8 are con- tor member. With this structural similarity in view, anected t?ge!her by a commu~catI?n cable 12.. ~he portion of only one set of the components of the secondcommurucation. cable 12 I?e~ts SIgnal transmission 35 actuator operation control circuit 8 is shown in FIG. 2.

between ~e main contrlC~CUIt13 and the first ac~- The decoder 19 a has an input terminal connectedtor operation control circuit 7 when a first exclusive with a first fixed contact 26a of a first changeover de-communication cable 17 (described later) is damaged or vice or switch25a. The encoder 22a has an input termi-out of order, or between the main control circuit 13 and nal connected with a first fixed contact 30a of a secondthe second actuator operation control circuit 8 when a 40 changeover device or switch 29a. The operation of thesecond exclusive communication cable 18 (described first and second switches 25a, 29a is controlled by alater) is damaged or out of order. switching (SW) unit 33a to alternatively connect theThe main control circuit 13, likewise the first and decoder 19a and the encoder 22a with the exclusive

second actuator operation control circuits 7,8, is mainly comminication cable 17 (FIG. 1) or the communicationcomposed of a microprocessor of a per se known con- 45 cable 12.struction and is supplied with various signals represent- The SW unit 33a serves to changeover the first anding the engine speed (r.p.m.) delivered from a revolu- second switches 25a, 29 a based on a control signal de-tion sensor 14, the shift/select set position delivered livered from the main control circuit 13. The firstfrom a shiftlever sensor 15. the amount of depression of switch 25 a has a second fixed contact 27a and a mov-an accelerator pedal delivered from an accelerator 50 'able contact 28a additional to the first fixed contact 26a.pedal sensor 16, and the vehicle speed delivered from a Likewise, the second switch 29 a has a second fixedspeed sensor (not shown). The main control circuit 13 contact 31a and a movable contact 32a additional to thethen computes target positions of the clutch 4 and the first fixed contact 3&. The second fixed contact 27a ofgear transmission 3 based on the input signals and re- the first switch 25 a is connected with a first fixedspectively provides the first and second actuator opera- 55 contact 26a of a first changeover device or switch 25btion control circuits 7, 8, with the thus computed target of the second actuator operation control circuit 8positions in the form of proper signals. The main con- through a first cable 12a which constitutes one part oftrol circuit 13 further serves to control the operation of the communication cable 12. The second fixed contactan air conditioner, display units and indicators, etc. of 31a of the second switch29a isconnected to a first fixedthe automobile. The main control circuit 13 and the first 60 contact 30b of a second changeover device or switchand second actuator operation control circuits 7, 8 are 29b of the second actuator operation control circuit 8connected by the above-mentioned first and second through a second cable 12b which constitutes the otherexclusive communication cables 17, 18. part of the communication cable 12. Thus, upon receiptFIG. 2 shows the general construction of the first of the control signal from the SW unit 33a, the movable

actuator operation control circuit 7 and a connecting 65 contacts 28a, 32a of the first and second switches 25a,part or junction between the first and 'Second actuator 29a are brought into contact with the second fixedoperation control circuits 7,8 composed of the commu- contacts 27a, 31a, respectively, At the same time, thenication cable 12. control signal from the SW unit 33a changes over mov-


10/12

54,884,201

able contacts 28b, 32b of the first and second switches25b, 29b of the second actuator operation control circuit8 into contact with the first fixed contacts 26b, 30b.Consequently, data transmission/reception between thesecond actuator operation control circuit 8 and the main 5control circuit 13 is performed through the first exclu-sive communication cable 17, the first actuator opera-tion control circuit 7 and the communication cable 12.For purposes of illustration, the CPU 24a as shown in

FIG. 2 is structurally independent of other components 10of the first actuator operation control circuit 7, how-ever, in practice, the CPU 24a selfcontains the functionof the decoder 19 a and other components of the firstactuator operation control circuit 7. This is also true incase of the second actuator operation control circuit 8. ISOperation of the automatic gear change device of the

foregoing construction will be described below withreference to FIGS. 3 through 6.The data transmission/reception between the main

control circuit 13 and the first actuator operation con- 20trol circuit 7 (or the second actuator operation controlcircuit 8) is performed in the manner as shown in FIG.3. At first, target position data for the clutch 4 (or thegear transmission 3) is transmitted from the main con- 25trol circuit 13 to the first actuator operation controlcircuit 7 (or the second actuator operation control cir-cuit 8)in the form of serial digital signals for a period oftime tl shown in this figure. Upon completion of thisdata transmission, the first actuator operation control 30circuit 7 (or the second actuator operation control cir-cuit 8) transmits the actual set position data (hereinafterreferred to as "actual position data") of the clutch 4 (orthe gear transmission 3)to the main control circuit 13inthe form of serial digital signals for a period of time t2. 35Then the main control circuit 13 computes the targetposition data again based on the actual position datathus transmitted and input signals indicative of variousvehicle travelling conditions such as engine r.p.m. Aftera predetermined period of time T has elapsed, the thus 40computed target position data are transmitted again tothe first actuator operation control circuit 7 (or thesecond actuator operation control circuit 8). The fore-going cycle of operation is repeated at equal time inter-vals T. 45FIG. 4(a) shows an example ofthe flow of the control

performed in the main control circuit 13 when it trans-mits the target position data. The main control unit 13produces offering signals at the aforesaid predetermined

intervals T whereupon the control is commenced at a 50step 100.In the next step 102,a determination is made asto whether or not the reception flag is set. If "YES", i.e.the determination indicates a set condition of the recep-tion flag in which data transmission from the main con-trol circuit 13ispermitted (namely, the data reception is 55prohibited), the target position data are tansmitted instep 104. Conversely, if the determination in step 102 shows a

reset ("NO") condition of the reception flag in whichdata transmission isprohibited due to the presence of an 60accident or trouble in the communication lines betweenthe main control circuit 13and the first actuator opera-tion control circuit 7 or between the main control cir-

cuit 13 and the second actuator operation control cir-cuit 8, the control goes on to step 108. In step 108, a 65back-up processing is performed to eliminate or removethe trouble. The back-up processing includes determi-nation of the mode of trouble which is achieved by one

6or more subroutines. Then the control proceeds to step110 to complete the series of steps of the operation.After the data transmission in step 104, the control

goes on to step 106 in which the reception flag is reset.Thus the main control circuit 13is placed in a conditionready state for reception of data delivered from the firstactuator operation control circuit 7 (or the second actu-ator operation control circuit 8). The step 106 is fol-lowed by the step 110 in which the successive steps ofoperation come to an end.FIG. 4(b) is a control flowchart showing the data

reception performed by the main control circuit 13.Upon transmission of actual position data from the

first actuator operation control circuit 7 (or the secondactuator operation control circuit 8), the main controlcircuit 13 produces an offering signal in step 112 topermit the reception of signals. Upon production of theoffering signal, the control proceeds from step 112 tostep 114 in which a reception flag is set to prevent sub-sequent reception of undesired signals such as noise.Then, a determination is made as to whether or not thereception data are error code in step 116. To achievethis determination, the extent of actual position datawhich are transmissible from the first actuator opera-tion control circuit 7 (or the second actuator operationcontrol circuit 8) is previously assigned to hexadecimalnotation codes, for example, and any other data areassigned to error codes. If the determination shows acondition free of error code, then the control goes on inthe direction "NO" to step 118.Conversely, ifthe deter-mination indicates the presence of an orror code, thecontrol proceeds in the direction "YES" to step 120.In step 118,the reception data are stored for saving in

a predetermined memory. The thus stored receptiondata are used for computation of new target positiondata. Thereafter, the control goes on to step 122 tocomplete the successive steps of the operation.In the step 120, the reception data assigned to error

codes are stored in a predetermined memory. The thusstored error codes are subjected to the back-up process-ing when the control goes back to the main routine.Then the control proceeds to step 122 to complete thesuccessive steps of the data reception operation.FIOS. 5(a), 5(b) and 6 show the flow of the control

performed in the first actuator operation control circuit7 (or the second actuator operation control circuit).In FIG. 5(a), there is shown a control flowchart illus-

trative of data transmission/reception of the first actua-tor operation control circuit 7 (or the second actuatoroperation control circuit 8). When the main controlcircuit 13 performs data transmission, the first actuatoroperation control circuit 7 (or the second actuator oper-ation control circuit 8) produces an offering signal forpermitting data reception whereupon the control iscommenced in step 130.In the next step 132,a receptionflag is set in the same manner as done in step 114 statedabove, and the control proceeds to step 133.In step 133, a determination is made as to whether or

not the input data relate to the first actuator operationcontrol circuit 7 or the second actuator operation con-trol circuit 8. If the input data are determined as being

related to the first actuator operation control circuit 7,then the control goes on in the direction "YES" to step134. Conversely, if the input data are determined asbeing related to the other control circuit 8, then thecontrol proceeds in the direction "NO" to step 160.


11/12

74,884,201

Step 134 and steps 136 and 138 are identical to theaforesaid steps 116, 118and 120,respectively, and hencerequire no further description.Subsequent to step 136, the actual position data are

transmitted in step 140 and the control goes on to step 5144 to complete the processing operation.

Step 138 is followed by step 142 in which indicationdata are transmitted to indicate that a back-up process-ing to be performed in the presence of an error code inthe reception data is now in progress. Thereafter, the 10control goes on to step 144 to complete the processingoperation.In step 160, the reception data are transmitted

through the first cable 12 a to the second actuator opera-tion control circuit 8 dependent on the result of deter- 15mination in step 133. Stated more specifically, if thedetermination in step 133 indicates a "NO" condition,the SW unit 33a of the first actuator operation controlcircuit 7 produces an output signal to changeover thepositions of the respective movable contacts 2 8a , 3 2a of 20the first and second switches 2 5a , 2 90 from the connec-tion with the first fixed contacts 2 60 , 3 00 to the connec-tion with the second fixed contacts 27a, 31a, therebypermitting data transmission as stated above (a controlflow performed in the second actuator operation con- 25trol circuit 8 will be described later with reference toFIG. 6). Then the control goes on to step 162 in whichthe reception of the actual position data delivered fromthe second actuator operation control circuit 8 is per-formed. The actual position data thus received are then 30transmitted to the main control circuit 13 in step 164.Then the control goes on to step 144 to complete thepocessing operation. .After the completion of the successive steps of opera-

tion in step 144, the control returns to the main routine 35

in which a control signal is suppliedto the clutch 4 (orthe gear transmission 3) to place the latter in the targetposition.FIG. 5(b) shows the flow of the control flow which is

performed prior to the data reception of the first actua- 40tor operation control circuit 7 (or the second actuatoroperation control circuit 8). The control is commencedin step 146 and then goes on to step 148 in which adetermination is made as to whether or not a reception_is~ ~If the reception flag is set to thereby prohibit data

reception, the control proceeds in the direction "YES"to step 154 in which the reception flag is reset, therebypermitting data reception. Step 154 is followed by step156 in which the control operation is completed. There- S Oafter the control goes on to a non-illustrated main rou-tine in which successive steps of operation are per-formed in the same manner as done in the control rou-tine shown in FIG. 4(a).If the-determination in step 148 shows a reset ("NO") 55

condition of the reception flag, the control goes on tostep 150in which a back-up flag isset. Since this controlroutine is performed before the first actuator operationcontrol circuit 7 (or the second actuator operation con-trol circuit 8) is set in a condition ready for data recep- 60tion, the reset condition of the reception flag which isdetermined in step 146 means that the first actuatoroperation control circuit 7 (or the second actuator oper-ation control circuit 8)which should be held in a condi-

tion to prohibit data reception isplaced in a condition to 65accept data reception due to the absence of data trans-mission from the main control circuit 13. Consequently,a back-up flag is set as a mark or sign so as to indicate a

8defective condition for proceeding a back-up process-ing in the main routine, not illustrated here.Step 150 is followed by step 152 in which an error

code indicative of the occurrence of an accident ortrouble in a communication line between the main con-trol circuit 13 and the first actuator operation control

circuit 7 (or the second actuator operation control cir-cuit 8) is transmitted to the main control circuit 13.Then the control goes on to step 156 to complete theprocessing operation.FIG. 6 shows the flow of the control for performing

data transmission/reception between the second actua-tor operation control circuit 8 (or the first actuatoroperation control circuit 7) and the main control circuit13 through the communication cable 12. The control iscommenced in step 168 and then goes on to step 170 inwhich a determination is made as to whether or not thereception data have departed from the first actuatoroperation control circuit 7 for back-up processing. If"YES", the control proceeds to step 172 in which theSW unit 33b changes over the movable contacts 28b,32b of the first and second switches 25b, 29b into en-gagement with the first fixed contacts 26b, 30b tothereby store the reception data in a predeterminedmemory. Then the control goes on to step 174.In step 174, the actual position data on the clutch 4

(or the gear transmission 3) are fed from the secondactuator operation control circuit 8 successivelythrought the second cable 12b, the first actuator opera-tion control circuit 7 and the first exclusive cable 17 tothe main control circuit 13.The data transmission/reception between the first

actuator operation control circuit 7 and the main con-trol circuit 13 via the communication cable 12 is per-formed in essentially the same manner as the above-

mentioned data transmission/reception.In the illustrated embodiment, the connection be-tween the communication cable 12 and the first andsecond actuator operation control units 7,8 isprovidedfor the data transmission/reception between the secondactuator operation control circuit 8 and the main con-trol circuits 13 via the communication cable 12. Theconnection or junction between the communicationcable 12 and the first and second actuator operationcontrol units 7, 8 for enabling data transmission/recep-tion between the first actuator operation control circuit7 and the main control circuit 13through the communi-cation cable 12is not illustrated but such data transmis-sion/reception can be performed by providing an addi-tional set of connecting components which is the sameas the connection component set shown in FIG. 2.Obviously, various modifications and variations of

the present invention are possible in the light of theabove teachings. It is therefore to be understood thatwithin the scope of the appended claims the inventionmay be practiced otherwise than as specifically de-scribed.What is claimed is:1. An automatic gear change device for controll ing

the operation of a gear transmission and a clutch, saidclutch for engaging and disengaging said gear transmis-sion, said device comprising:a first actuator connected to said clutch, said firstactuator operating said clutch in response to a firstactuator signal;

a second actuator connected to said gear transmis-sion, said second actuator operating said gear trans-mission in response to a second actuator signal;


12/12

94,884,201

10a first actuator operation control means, connected to and second position data respectively correspond-said first actuator, for outputting said first actuator ing to said first and second position signals.signal in response to target data; 2. An automatic gear change device as claimed in

a second actuator operation control means, con- claim 5, said first actuator operation control meansnected to said second actuator, for outputting said 5 comprising:second actuator signal in response to said target a decoder for converting said target data receiveddata; from said main control means into corresponding

a main control means, connected to said first actuator electrical signals;operation control means by a first signal path and a variable gain regulator connected to said"decoder

t d to said d ti tr I 10 for converting each of said electrical signals to aconnec e 0 sai secon opera IOncon 0 means corresponding signal having a predetermined volt-by a second signal path, for outputting said target age level;data; a pulse-width modulator connected to said variable

a communication means for electrically interconnect- gain regulator for modulating the pulse-width ofing said first actuator operation control means and 15 said signal having a predetermined voltage levelsaid second actuator operation control means; and for supplying the thus generated modulated

a first stroke sensor connected to said first actuator signal to said first actuator; andand said first actuator operation control means, said an encoder connected to said first stroke sensor forfirst stroke sensor outputting to said first actuator outputting said first position data in response tooperation control means a first position signal in 20 said first position signal.accordance with a stroke of said first actuator; and, 3. An automatic gear change device as claimed in

a second stroke sensor connected to said second actu- claim 1, wherein said first actuator operation controlator and said second actuator operation control means comprises a switching unit for selectively estab-means, said second stroke sensor outputting to said lishing an electrical signal path between said main con-second actuator operation control means a second 25 trol means and said first actuator operation controlposition: signal in accordance with a stroke of said means, and between said second actuator operationsecond actuator; control means and said first actuator operation control

wherein a first electrical signal path is established means.between said main control means and said first 4. An automatic gear change device as claimed inactuator operation control means through said 30 claim 2, wherein said first actuator operation controlsecond signal path and said second actuator opera- means further comprises a switching unit for selectivelytion control means and said communication means establishing an electrical signal path between said main

control means and said first actuator operation controlwhen said first signal path is inoperative; means, and between said second actuator operation

wherein a second electrical signal path is established 35 control means and said first actuator operation controlbetween said main control means and said second means.actuator operation control means through said first 5. An automatic gear change device as claimed insignal path and said first actuator operation control claim 4, wherein said first actuator operation controlmeans and said communication means when said means further comprises a central processing unit forsecond signal path is inoperative; and, 40 controlling the operation of said decoder, said variable

wherein said first and second actuator operation con- gain regulator, said pulse-width modulator, said en-trol means respectively output first and second coder, and said switching unit.position data to said main control means, said first * * * * *

45

50

55

60

65

automatic_gear_changer

Documents