CA1217070A - Automatic clutch control system - Google Patents
Automatic clutch control systemInfo
- Publication number
- CA1217070A CA1217070A CA000456211A CA456211A CA1217070A CA 1217070 A CA1217070 A CA 1217070A CA 000456211 A CA000456211 A CA 000456211A CA 456211 A CA456211 A CA 456211A CA 1217070 A CA1217070 A CA 1217070A
- Authority
- CA
- Canada
- Prior art keywords
- clutch
- solenoid valves
- speed
- sensor
- stroke
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
- B60W10/00—Conjoint control of vehicle sub-units of different type or different function
- B60W10/02—Conjoint control of vehicle sub-units of different type or different function including control of driveline clutches
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
- B60W10/00—Conjoint control of vehicle sub-units of different type or different function
- B60W10/04—Conjoint control of vehicle sub-units of different type or different function including control of propulsion units
- B60W10/06—Conjoint control of vehicle sub-units of different type or different function including control of propulsion units including control of combustion engines
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
- B60W10/00—Conjoint control of vehicle sub-units of different type or different function
- B60W10/10—Conjoint control of vehicle sub-units of different type or different function including control of change-speed gearings
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
- B60W40/00—Estimation or calculation of non-directly measurable driving parameters for road vehicle drive control systems not related to the control of a particular sub unit, e.g. by using mathematical models
- B60W40/10—Estimation or calculation of non-directly measurable driving parameters for road vehicle drive control systems not related to the control of a particular sub unit, e.g. by using mathematical models related to vehicle motion
- B60W40/105—Speed
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D48/00—External control of clutches
- F16D48/06—Control by electric or electronic means, e.g. of fluid pressure
- F16D48/066—Control of fluid pressure, e.g. using an accumulator
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
- B60W2510/00—Input parameters relating to a particular sub-units
- B60W2510/06—Combustion engines, Gas turbines
- B60W2510/0638—Engine speed
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
- B60W2520/00—Input parameters relating to overall vehicle dynamics
- B60W2520/10—Longitudinal speed
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
- B60W2540/00—Input parameters relating to occupants
- B60W2540/10—Accelerator pedal position
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
- B60W2710/00—Output or target parameters relating to a particular sub-units
- B60W2710/02—Clutches
- B60W2710/021—Clutch engagement state
- B60W2710/023—Clutch engagement rate
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D2500/00—External control of clutches by electric or electronic means
- F16D2500/10—System to be controlled
- F16D2500/102—Actuator
- F16D2500/1026—Hydraulic
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Transportation (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- General Engineering & Computer Science (AREA)
- Automation & Control Theory (AREA)
- Mathematical Physics (AREA)
- Hydraulic Clutches, Magnetic Clutches, Fluid Clutches, And Fluid Joints (AREA)
- Control Of Driving Devices And Active Controlling Of Vehicle (AREA)
Abstract
AUTOMATIC CLUTCH CONTROL SYSTEM
ABSTRACT OF THE DISCLOSURE
An automatic clutch control system, for use in automobiles, using a microcomputer, including an accelerator pedal sensor for detecting accelerator position; an engine speed sensor for detecting engine speed; a clutch stroke sensor for detecting clutch stroke; an automobile speed sensor for detecting automobile speed; and a controller for controlling opening or closing of solenoid valves, gear change of a transmission, and opening or closing of a throttle actuator, based on predetermined stored data and based on signals transmitted from the sensors.
The automatic clutch control system consequently can automatically control the clutch moving time and clutch moving speed for easy driving under all driving conditions.
Moreover, while the clutch control system is automatic, it can use dry-type single-plate clutches and sliding-mesh-type transmissions as in manual and semiautomatic transmissions.
ABSTRACT OF THE DISCLOSURE
An automatic clutch control system, for use in automobiles, using a microcomputer, including an accelerator pedal sensor for detecting accelerator position; an engine speed sensor for detecting engine speed; a clutch stroke sensor for detecting clutch stroke; an automobile speed sensor for detecting automobile speed; and a controller for controlling opening or closing of solenoid valves, gear change of a transmission, and opening or closing of a throttle actuator, based on predetermined stored data and based on signals transmitted from the sensors.
The automatic clutch control system consequently can automatically control the clutch moving time and clutch moving speed for easy driving under all driving conditions.
Moreover, while the clutch control system is automatic, it can use dry-type single-plate clutches and sliding-mesh-type transmissions as in manual and semiautomatic transmissions.
Description
A~rO~ATIC CLUTCH CONTROI.SYSTEM
aACKGRCUND OF THE INNEN$ICN
1. Field of the Invention The present invention relates to a clutch control system, more particularly to a method and apparatus for an automatic clutch control system using a microcomputer.
The present invention is advantageously used, for example, for automobiles having conventional dry-type single~
plate clutches and sliding-mesh-type transmissions.
The automatic clutch control system according to the present invention can automatically control the clutch moving time, clutch moving speed, and gear changes under a predetermined control program stored in a microcomputer, thus allowing easy driving under all driving conditions.
aACKGRCUND OF THE INNEN$ICN
1. Field of the Invention The present invention relates to a clutch control system, more particularly to a method and apparatus for an automatic clutch control system using a microcomputer.
The present invention is advantageously used, for example, for automobiles having conventional dry-type single~
plate clutches and sliding-mesh-type transmissions.
The automatic clutch control system according to the present invention can automatically control the clutch moving time, clutch moving speed, and gear changes under a predetermined control program stored in a microcomputer, thus allowing easy driving under all driving conditions.
2. Description of the Prior Art As is well known, three main types of transmissions are now in use for clutch control and gear change in automobiles:
manual transmissions, using dry-type single-plate clutches and sliding-mesh-t~pe transmissions, which are manually operated by ~ a clutch pedal and a change lever; semiautomatic transmissions, also using dry-type single-plate clutches and sliding-meshrtype transmissions, which have a gear change mechanism manually operated by a change lever and a clutch automatically controlled by a computer; and automatic transmissions, Eor example, using torque converters and planetary-gear~type auxiliary transmis-sions, which are automatically controlled by a computer control-ler.
As also well known, each of these types of transmission have their own advantages and disadvantages. The main disadvan-tages oE manual transmissions are troublesome operability, poor smoothness of change, and susceptibility of efficiency to driving characteristics o~ individual drivers. The main disadvantage of 7~)70 semiautomatic transmissions is poor smoothness of change. Finally, t~e main disadvantages oE automatic transmissions are poor gas mi]eaye, slow response time, and high cost.
Although technical improvements have been made alleviating the above disadvan-tages, these improvements are still not sufficient.
SUMMARY OF THE INVENTION
The primary object of the present invention is to provide an automatic clutch control system, for use in automobiles, using a microcomputer and eliminating the disadvantages in the prior art.
Another object of the present invention is to provide an automatic clutch control system enabling highly precise, automatic control of the clutch moving time and clutch moving speed under various driving conditions.
Still another object of the present invention is to provide an automatic clutch control system enabling use of conventional dry-type single-plate clutches and sliding-mesh-type transmissions.
In accordance with one embodiment of the present invention, there is provided an automatic clutch control apparatus, for use in automobiles which have an accelerator pedal, a clutch actuated via solenoid valves, a throttle actuator on an engine and a transmission having changeable gears, comprising:
accelerator sensing means, coupled to the accelerator pedal, for sensing accelerator pedal position;
engine speed sensing means r coupled to the engine, for sensing engine speed;
clutch stroke sensing means, coupled to the clutch, for sensing clutch stroke;
automobile speed sensing means, coupled to the transmission, for sensing automobile speed; and 7~
control means, operatively connected to the accelerator sensing means, -the engine speed sensing means, the clutch stroke sensing means and the automobile speed sensing means, for controlling opening and closing of the solenoid valves, the gear change of the transmission and opening and closing of the throttle actuator, based on predetermined stored data and based on the position of the accelerator pedal, engine speed, clutch stroke and automobile speed, for automatic control of clutch moving time and clutch moving speed.
In accordance with another embodiment of the present invention, there is provided a method of automatic clutch control for automobiles, using a microcomputer and comprising the steps of:
(a) detecting accelerator position by an accelerator pedal sensor, engine speed by an engine speed sensor, clutch stroke by a clutch stroke sensor, and automobile speed by an automobile speed sensor to generate sensor data;
(b) comparing the sensor data with predetermined stored data and calculating a clutch moving time and a clutch moving speed, based on the predetermined stored data, for various driving conditions;
(c) controlling at least one oE opening and closing of solenoid valves based on signals generated from flip-flop circuits via counters activated by the calculating in step (b), two of -the solenoid valves being series-connected solenoid valves and a quantity of fluid flow being controlled by overlapping timing of the least one of opening and closing of the series-connected solenoid valves using the microcomputer; and (d) controlling the clutch moving time and clutch moving speed by means of a clutch actuator controlled by the solenoid valves.
` ~21~07~
In accordance with still another embodiment of the present invention, there is provided a method of automatic clutch control, for automobiles, using a microcomputer, comprising the steps of:
(a) detecting accelerator position by an acclerator pedal sensor, engine speed by an engine speed sensor, clutch stroke by a clutch s.roke sensor, and automobile speed by an automobile speed sensor to aenerate sensor datai (b) comparing the sensor data with predeter.
mind stored data and calculating a clutch moving time and a clutch moving speed, based on the predetermined stored data, for various driving conditions;
(c) controlling at least one of opening and closing of solenoid valves based on signals generated fr,om flip-flop circuits via counters activated by said calculating in step (b); and (d) controlling the clutch moving time and speed by means of a clutch actuator controlled by the solenoid valves, using a predetermined value from - clutch disengagement to clutch slip and using one of a set of predetermined values corresponding to a selected one of parameters of driving conditions irom clutch slip to clutch engagement.
In yet another embodiment of the present invention, there is provided a method of automatic clutch control for automobiles, using a microcomputer and comprising the steps of:
3a C
.
~L7Q7~
(a) ae~ecting accelerator position by an accelerator pedal sensor, engine speed by an engine speed sensor, clutch stroke by a clutch s.ro~e sensor, and automobile speed by an automobile speed sensor to generate sensor data;
(b) comparing the sensor data with predeter-mined stored data and calculating a clutch moving time and a clutch moving speed, based on the predetermined : stored data, for various driving conditions;
(c) controlling at least one of opening and closing of solenoid valves based on signals generated from Ilip-flop Cil-CUits via counters activated by said calculating in step (b); and (d) controlling the clutch moving speed and time by means of a clutch actuator controlled by the solenoid valves, using a constant value from clutch disengagement to clutch slip and using one of a set of predetermined values corresponding to a selected one of parameters of driving conditions from clutch slip to clutch engagement.
St..i.ll another embodiment of the present inventi~Qn provides a method of automatie clutch control for automobiles, using a mieroeomputer and eornprising the steps of:
, (a) detecting accelerator position by an accelerator pedal sensor, engine speed by an engine speed sensor, clutch stroke by a clutch stroke sensor, and automobile speed by an autornobile speed sensor to generate sensor data;
3b LZ~ 70 (b) cc"paring the sensor data .ith predeter-mined stored data and calculating a c~utch moving time znd a clutch movinq speed, based on the predetermined stored data, for various driving conditions;
(c) controlling at least one of opening and closing of solenoid valves base~ on signals generated from flip-flop circuits via counters activated by said calculating in step (b); and (d) controlling the clutch moving speed and time by means of a clutch actuator controlled by the solenoid valves, using one of a set of pre~etermined constant values corresponding to a selected one of parameters of driving conditions from clutch slip to near clutch engagement and then using a preaetermined constant speed to clutch engagement.
:
; Yet another embodiment of the present invention provides a method of automatic clutch control for automobiles, using a microcomputer and comprising the steps of:
~ (a) detecting accelerator position by an accelerator pedal sensor, engine speed by an engine speed sensor, clutch stroke by a clutch stroke sensor, and automobile speed by an automobile speed sensor to generate sensor data;
(b) comparing the senso-r data with predeter-mined stored data and calculating a clutch rno~7ing time and a clutch moving speed, based on the predeterrnined stored data, for various driving conditions;
: 3c ~`~' . ' .
~Z~7(1 70 (c) cGntrollir,c at ledst one of o?ening and closing of solenoid valves based on signals generated from flip-flop circuits via counters activated by said calculating in step ~b), two of the solenoid valves being provided in series in a supply side fluid passage and another two of the solenoid valves being pl-ovided in parallel in an e~haust side fluid passage, a auantity of fluid flow being controlled by overlapping timing of the at least one of opening and closing of the solenoid valves of both the supply and e~haust sides using the microcomputer; and .
(d) controlling the clutch moving time and clutch moving speed hy means of a c1utch actuator controlled by the solenoid valves.
Yet another aspect of the invention provides an automatic clutch control system for an automobile having an engine with a throttle, an accelerator pedal and a transmission with a clutch, the system comprising~
I
a throttle actuator, coupled to the throttle, for adjustment of the throttle;
a clutch actuator, coupled to the clutch, for controlling engagement and disengagement of the clutch;
3d , C
~2~7(;~7~ , solenoid valves, hydraulically connected to said clutch actuator, for controlling the movement of said clutch actuator;
clutch stroke sen~ing means, coupled to said clutch actuator, for sensing clutch stroke;
accelerator sensing means, coupled to the accelerator pedal, for sensing accelerator position;
engine speed sensing means, coupled to : the engine, for sensing engine speed;
automobile speed sensing means, coupled to the transmission, for sensing automobile speed; and control means, operatively connected to said clutch stroke sensing means, said accelerator sensing means, said engine speed sensing means and said automobile speed sensing means, for controlling opening and-closi~ng o~ the solenoïd valves, gear change.of the transmissi.on and adjustments of the throttle actuator, in dependence upon the conditions sensed by said clutch stroke, accelerator, engine speed and automobile speed sensing means, to provide automatic control of clutch moving time.and clutch moving speed.
.
3e 17~7~
The present invention enables easy driving under all driving conditions and improved operability and gas mileage compared with conventional manual, semiautomatic, and Eully automatic transmis-sions. Moreover, it can be used with dry-type single-plate elutches and sliding-mesh-type transmissions used in conventional manual and semiautomatic transmissions.
BRIE~ DESC~IPTICN QF THE DRAWLNGS
In the drawings, Fig. 1 is a schematie bloek diagram of an automatie eluteh control system in a conventional semiautomatie transmission;
Fig. 2 is a partial schematie view of a clutch aetuator shown in Fig. l;
Fig. 3 is a timing ehart of drive current applied to a solenoid valve (A), the quantity of oil flow through one solenoid valve (B)" and the quantity of oil flow through another solenoid valve (C); -~
Fig. 4 is a schematic block diagram of an-automatic clutch control system according to the present invention;
Fig. 5 is a schematic block diagram of a hydraulic control circuit including the solenoid valves controlled by the -i rontroller -hohn in Fig. 4 3f 1~L7(~7~) Fig. 6 is a schematic block diagram for explaining the automatic clutch control system shown in Fig. 4;
Fig. 7 to Fig. 9 are graphs for explaining relations between - clutch stroke and clutch moving time (Fig. 7) and between clutch stroke and clutch moving speed (Fig. 8 and Fig. 9);
Fig. lO shows timing charts for opening and closing of valves and the quantity of fluid flow therethrough;
Fig. ll is a basic block diagram of the controller shown in Fig. 4; and lOFig. 12 is a flow chart of clutch control procedure performed in the controller shown in Fig. ll.
DESCRIPTIGN Q~ THE PREE~RRED EMBODIM~NIS
In general, rotation of an automobile engine is transmitted to the shaft of a transmission mechanism by a dry-type single-plate clutch. To control the clutch engagement, a hydrauliccontrol actuator is used. The hydraulic control actuator is constituted by a hydraulic cylinder used to engage and disengage the clutch and a plurality of solenoid valves used to control the motion of the hydraulic cylinder. Control of the hydraulic actuator, i.e., control of the solenoid valves, is effected mechanically in manual transmissions and electronically in semiautomatic transmissions.
Before describing the preferred embodiments of the present invention, an explanation will be given of a conventional clutch control system for a semiautomatic transmission using a dry-type single-plate clutch and hydraulic control actuator.
Referring to Fig. l, reference numeral l is an accelerator pedal, lA an accelerator pedal sensor, 2 an engine, 2A an engine speed sensor, 3 a throttle actuator, 4 a clutch, 5 a transmis-sion, 6 a clutch actuator, 6A a clutch stroke sensor, 7 asolenoid valve group, 8 an oil pump, 9 an oil tank, lO a control unit, and ll an automobile speed sensor.
The control unit lO, constituted by a microcomputer, con-91 217C~
trols the throttle actuator 3 and the solenoid valve group 7based on a signal transmitte~ from the accelerator pedal sensor lA, a signal transmitted from the engine speed sensor 2A, a signal transmitted from the clutch stroke sensor 6A, and a signal transmitted from the automobile speed sensor 11. The control unit 10 also feeds back the stroke signal transmitted from the clutch stroke sensor 6A to control the opening of the solenoid valve group 7 for engagement, slip, or disengagement of the clutch based on the clutch moving speed, as defined by clutch engagement, clutch slip, clutch disengagement, change in engine speed, automobile speed, and other driving conditions.
In other clutch control systems used for semiautomatic transmission, the system feeds back a stroke signal transmitted from a clutch stroke sensor, engine speed sensor, and automobile speed sensor to control the duty ratio (ratio of opening and closing time of valve) of solenoid valves by a control unit so as to obtain both a clutch moving speed and clutch moving time defined by engine speed, automobile speed, and other driving conditions.
However, it is difficult to obtain the desired clutch moving speed and clutch moving time by controlling the opening or closing of the solenoid valves because it is necessary to finely control the duty ratio of the opening or closing of the valves, which necessitates complex valve control.
The above problems will be explained in detail hereinafter with respect to Fig. 2 and Fig. 3. Referring to Fig. 2, as mentioned above, the hydraulic control actuator is constituted by a clutch actuator, i.e., an oil cylinder 6, and a plurality of solenoid valves (Vl to V3). A piston 6B equipped with a piston rod 6C is provided in the oil cylinder 6. The solenoid valve Vl is provided for exhaust in a small diameter fluid passage, and the solenoid valve V2 is provided for exhaust in a large diameter fluid passage. The solenoid valve V3 is provided for supply.
~L'7~7~
Although only two exhaust solenoid valves Vl and V2 are shown in the drawing, generally a plurality of fluid passages having the same diameters are provided in the actuator and each fluid passage is controlled by a solenoid valve. In the case shown in the drawing, the solenoid valve V2 is used for coarse control of the oil flow, and solenoid valve Vl for fine control of the oil flow.
Referring to Fig. 3, when a drive cnrrent having a pulse waveform as shown in ~A) is applied to the solenoid valves Vl and V2, the oil flow through the solenoid valve Vl in the small diameter fluid passage is shown by (B), and the oil flow through the solenoid valve V2 in the large diameter fluid passage is shown by (C).
The oil flows through the solenoid valves Vl and V2 are constant so long as the pulse waveform of the drive current is the same, i.e., has the same pulse width. The oil flow, however, changes when the pulse width becomes smaller or along with increasingly smaller diameters of fluid passages, in order to achieve finer control, whereby the control of the hydraulic actuator becomes unstable. Acco~dingly, it is difficult to obtain precise control of opening or closing of solenoid valves so as to obtain the desired clutch moving speed and clutch moving time~
An automatic clutch control system according to the present invention will now be explained in detail. As explained above, the automatic clutch control system according to the present invention can be used with conventional dry-type single-plate clutches and sliding-mesh-type transmissions. In the present invention, the change lever used in semiautomatic transmissions is eliminated and a transmission changer (drive mechanism) added instead. These clutch and drive mechanisms are controlled by a microcomputer controller~ Accordingly, the clutch control system according to the present invention is a fully automatic ~Z1707V
.
transmission using a conventional clutch and transmission.
~ eferring to Fig. ~, the automatic clutch control system is constituted by the same comFonents as shown in Fig. 1, except for a controller 100, a solenoid valve group 70, and a changer 12.
Components the same as in Fig. 1 are indicated by the same reference numerals.
Referring to Fig. 5, the clutch 4 is constituted by a clutch pressure plate 4A, clutch disk 4B, diaphragm spring qC, clutch release bearing 4D, clutch release lever 4E, clutch shaft 4F, and lever 4G. Reference numeral 2B is an engine flywheel; 701, 701', 702, and 703 solenoid valves in the solenoid qroup 70; B a battery; SW a power switch associated with an ignition switch;
and AC an accumulator.
The clutch 4 is controlled by controlling the opening or 15 closing of the solenoid valves 701, 701', 702, and 703 using the controller 100. The controller 100 consists of a microcomputer storing a program with respect to driving conditions. When the solenoid valves 701 and 701', for example, are actuated by the controller 100, pressurized fluid is supplied to the oil cylinder 6 from the oil pump 8. The piston 5B of the oil cylinder 6 is thus moved toward the right as indicated by the arrow line to disengage the clutch disk 4B. When the solenoid valves 702 and 703 are actuated by the controller 100, the pressurized fluid is exhausted from the oil cylinder 6. The piston 6B thus moves in the reverse direction due to the action of a return spring (not shown) to re-engage the clutch disk ~B.
This control of clutch engagcment and disengagement ~ill be explained in more detail hereinafter with respect to Figs. 6, 7, 8, 9, and 10.
The controller 100 stores various parameters, for example, a to d shown in Figs. 7 to 9, defining the relation between the clutch stroke and clutch moving time or between the clutch stroke and clutch moving speed based on various driving conditionst 9LZ~7~7~
such as upward or downward slopes, flat roads, and stopping. The controller 100 uses these parameters a to d and the signal transmitted from the clutch stroke sensor 6A, for example, a potentiometer, to calculate the desireable clutch moving speed and clutch moving time corresponding to the clutch stroke S and controls the solenoid valve group 70 based on the results of its calculations.
The control modes will be explained in more detail with respect to Figs. 7 to 9. Referring to Fig. 7, the ordinate indicates the clutch stroke (S) and the abscissa indicates the clutch moving time (T). The lines I, II, and III indicate clutch engagement (clutch on), clutch slip (half clutch), and clutch disengagement (clutch off). As is obvious from the graph, the clutch moving time is controlled to a predetermined gradually increasing value in the clutch operation from line III to line II
and controlled to one of a set of predetermined gradually increasing values corresponding to a selected one of the driving condition parameters a to d in the clutch operation from line II
to line I.
In Figs. 8 and 9, the ordinates indicate the clutch stroke (S) and the abscissas indicate the clutch moving speed (V). In the control modes of both Figs. 8 and 9, the clutch moving speed is controlled to a constant value in the clutch operation from line III to line II. In Fig. 8, the clutch moving speed is controlled to one of a set of predetermined gradually decreasing values corresponding to a selected one of the driving condition parameters a to d in the clutch operation from line II to line I.
In Fig. 9, the clutch moving speed is controlled to one of a set of predetermined constant values in the clutch operation from line II to near line I and to a predctermined constant value to line I.
Next, fine control of the solenoid valves 701, 701', 702, and 703 shown in Fig. 5 and Fig. 6 will be explained in reference -~-` lZ~ 7~
to Fig. 10 (A) to (D).
Referring to Fig. 10, as mentioned above, the open ("on") and close (noff") timings of each solenoid valve 701, 701', 702, - and 703 are controlled by the controller 100. The "on" and "off"
timings can be independently selected by the controller 100.
Generally, there is a time delay between the "on" and "off"
timings in different valves. As a result, the quantity of oil flow through the vaives changes gradually at the leading edges and trailing edges of the waveforms shown in Fig. 10.
In the case of two valves, when both valves are turned on nearly simultaneously by drive currents il and i2 and are left on for a long time, the quantity of oil flow Q is indicated by the hatched area in Fig~ 10 (A). When both valves are simultaneously turned on for a short time, the quantity of oil flow Q is as shown in Fig. 10 (B). When the upstream valve is changed from ~onn to "off" and the downstream valve is changed from "off" to "on~ the quantity of oil flow is as shown in Fiq. 10 (C).
As is obvious from the waveform shown in Fig. 10 (D), the overlapping of the "on~ and "off" timing of the valves affects the quantity of oil flow.
The ~ethod for controlling the quantity of oil flow accord-ing to the present invention is particularly advantageous when the solenoid valves 701, 701', 702, and 703 are controlled as shown in Figs. 10 (C) and (D). Now, in the embodiment shown, the solenoid valves 701 and 701' are provided in series in the supply sidc fluid passage, while the solenoid valves 702 and 703 are provided in parallel in the exhaust side fluid passage. In conventional systems using a single solenoid valve in the supply side, the solenoid valve has not been able to operate fast enough in accordance with a rapid succession of ~on" and "off"
instructions. As a result, conventionally, the quantity of oil flow through the valves during "on" and "off" timing has been unstable.
However, according to the present invention, "on" and "off" control of valves can be independently performed by the controller 100. Consequently, it is possible to control the solenoid valves 701, 701', 702, and 703 to operate at exactly the right timings. A stable flow of oil is possible even with an extremely small overlap of time in "on" timing.
Consequently, since the quantity of oil flow through each valve can be finely controlled by the microcomputer, the clutch moving speed and the clutch moving time can be controlled for various driving conditions.
Referring to Fig. 11, the controller 100 is mainly consti-tuted by analog-digital converters ADl to AD4, an address modi-fier AMO, memories Ml to M4, a comparator and calculator CAL, counters CNTl to CNT4, and flip-flop circuits FFl to FF4. The address modifier AMO, comparator and calculator CAL, and coun-ters CNT are incorporated in a central processing unit CPU.
An analog output detected by, for example, the accelerator pedal sensor lA is applied to the analog-digital converter ADl.
An analog output detected by, for example, the clutch stroke sensor 6A is applied to the analog digital converter AD2. The digital outputs from the analog-digital converters ADl and AD2 are applied to the memories Ml and M2, respectively, via the address modifier AMO. The digital outputs designate addresses in the memories (tables) Ml and M2.
Data read out from the tables is supplied to the compara-tor and calculator CAL and appropriately processed. In the mem-ory Ml, the resultant data and the pulse G are applied to the counter CNTl and the flip-flop FFl for presetting the counter CNTl and for setting the flip-flop FFl. When the flip-flop FFl is set, the transistor TRl turns on and the solenoid valve 701 is activated. The counter CNTl sequentially counts down from the preset number using the periodically input pulse T and re-sets the flip-flop FFl when reaching zero, based on a zero de-tecting signal generating from the counter CNTl itself.
B
1'7C~7~
The output "set signal~ of the ~lip-flop FF1 is applied to a base of a transistor TRl, as explained above, the transistor turns on and the solenoid valve 701 is activated. The flip-flop FFl is rese~ based on the zero detecting signal, the tran-sistor TR1 turns off, and the solenoid valve 701 is deacti-vated. Accordingly, the larger the preset number of the coun-ter CNT1, the longer the activating time (on time) of the sole-noid 701. If the gate value which controls output of the mem-ory M1 is stored in another table, for example, memory M2, the clutch moving speed and clutch moving time can be controlled as shown in Figs. 7 to 9.
Referring to Fig. 12, the signals from each sensor, i.e., the accelerator pedal sensor lA, the engine speed sensor 2A, the clutch stroke sensor 6A, and the automobile speed sensor 11, are first applied to the analog-digital converters at step l. These analog signals are converted to digital signals at step 2~ The digital signals transmitted from the analog-digital converters designate addresses in the tables at step 3.
The stored data is read out from the tables and applied to the comparator and calculator CAL at step 4. The comparator and calculator CAL compares the read out data with prestored data ; of driving conditions a, b, c, and d and calculates dif-ferentials for obtaining clutch moving time and clutch moving speed based on commands transmitted from the central processing unit CPU at steps 5 and 6. The resultant data is applied to the counters, which se~uentially count down from preset numbers based on the periodically input pulses at step 7. The flip-flop circuits are reset by other periodically input pulses when the counts become zero at step 8. The outputs of the flip-flop circuits are applied to the bases of the transistors and the transistors turn on. The solenoid valves are activated by the current flowing through the transistors at step 9. Consequent-ly, the cylinder stroke is controlled by the "on" or "off" tim-ing of each valve at step lO. Therefore, the clutch stroke can be suitably controlled for all driving conditions.
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manual transmissions, using dry-type single-plate clutches and sliding-mesh-t~pe transmissions, which are manually operated by ~ a clutch pedal and a change lever; semiautomatic transmissions, also using dry-type single-plate clutches and sliding-meshrtype transmissions, which have a gear change mechanism manually operated by a change lever and a clutch automatically controlled by a computer; and automatic transmissions, Eor example, using torque converters and planetary-gear~type auxiliary transmis-sions, which are automatically controlled by a computer control-ler.
As also well known, each of these types of transmission have their own advantages and disadvantages. The main disadvan-tages oE manual transmissions are troublesome operability, poor smoothness of change, and susceptibility of efficiency to driving characteristics o~ individual drivers. The main disadvantage of 7~)70 semiautomatic transmissions is poor smoothness of change. Finally, t~e main disadvantages oE automatic transmissions are poor gas mi]eaye, slow response time, and high cost.
Although technical improvements have been made alleviating the above disadvan-tages, these improvements are still not sufficient.
SUMMARY OF THE INVENTION
The primary object of the present invention is to provide an automatic clutch control system, for use in automobiles, using a microcomputer and eliminating the disadvantages in the prior art.
Another object of the present invention is to provide an automatic clutch control system enabling highly precise, automatic control of the clutch moving time and clutch moving speed under various driving conditions.
Still another object of the present invention is to provide an automatic clutch control system enabling use of conventional dry-type single-plate clutches and sliding-mesh-type transmissions.
In accordance with one embodiment of the present invention, there is provided an automatic clutch control apparatus, for use in automobiles which have an accelerator pedal, a clutch actuated via solenoid valves, a throttle actuator on an engine and a transmission having changeable gears, comprising:
accelerator sensing means, coupled to the accelerator pedal, for sensing accelerator pedal position;
engine speed sensing means r coupled to the engine, for sensing engine speed;
clutch stroke sensing means, coupled to the clutch, for sensing clutch stroke;
automobile speed sensing means, coupled to the transmission, for sensing automobile speed; and 7~
control means, operatively connected to the accelerator sensing means, -the engine speed sensing means, the clutch stroke sensing means and the automobile speed sensing means, for controlling opening and closing of the solenoid valves, the gear change of the transmission and opening and closing of the throttle actuator, based on predetermined stored data and based on the position of the accelerator pedal, engine speed, clutch stroke and automobile speed, for automatic control of clutch moving time and clutch moving speed.
In accordance with another embodiment of the present invention, there is provided a method of automatic clutch control for automobiles, using a microcomputer and comprising the steps of:
(a) detecting accelerator position by an accelerator pedal sensor, engine speed by an engine speed sensor, clutch stroke by a clutch stroke sensor, and automobile speed by an automobile speed sensor to generate sensor data;
(b) comparing the sensor data with predetermined stored data and calculating a clutch moving time and a clutch moving speed, based on the predetermined stored data, for various driving conditions;
(c) controlling at least one oE opening and closing of solenoid valves based on signals generated from flip-flop circuits via counters activated by the calculating in step (b), two of -the solenoid valves being series-connected solenoid valves and a quantity of fluid flow being controlled by overlapping timing of the least one of opening and closing of the series-connected solenoid valves using the microcomputer; and (d) controlling the clutch moving time and clutch moving speed by means of a clutch actuator controlled by the solenoid valves.
` ~21~07~
In accordance with still another embodiment of the present invention, there is provided a method of automatic clutch control, for automobiles, using a microcomputer, comprising the steps of:
(a) detecting accelerator position by an acclerator pedal sensor, engine speed by an engine speed sensor, clutch stroke by a clutch s.roke sensor, and automobile speed by an automobile speed sensor to aenerate sensor datai (b) comparing the sensor data with predeter.
mind stored data and calculating a clutch moving time and a clutch moving speed, based on the predetermined stored data, for various driving conditions;
(c) controlling at least one of opening and closing of solenoid valves based on signals generated fr,om flip-flop circuits via counters activated by said calculating in step (b); and (d) controlling the clutch moving time and speed by means of a clutch actuator controlled by the solenoid valves, using a predetermined value from - clutch disengagement to clutch slip and using one of a set of predetermined values corresponding to a selected one of parameters of driving conditions irom clutch slip to clutch engagement.
In yet another embodiment of the present invention, there is provided a method of automatic clutch control for automobiles, using a microcomputer and comprising the steps of:
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.
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(a) ae~ecting accelerator position by an accelerator pedal sensor, engine speed by an engine speed sensor, clutch stroke by a clutch s.ro~e sensor, and automobile speed by an automobile speed sensor to generate sensor data;
(b) comparing the sensor data with predeter-mined stored data and calculating a clutch moving time and a clutch moving speed, based on the predetermined : stored data, for various driving conditions;
(c) controlling at least one of opening and closing of solenoid valves based on signals generated from Ilip-flop Cil-CUits via counters activated by said calculating in step (b); and (d) controlling the clutch moving speed and time by means of a clutch actuator controlled by the solenoid valves, using a constant value from clutch disengagement to clutch slip and using one of a set of predetermined values corresponding to a selected one of parameters of driving conditions from clutch slip to clutch engagement.
St..i.ll another embodiment of the present inventi~Qn provides a method of automatie clutch control for automobiles, using a mieroeomputer and eornprising the steps of:
, (a) detecting accelerator position by an accelerator pedal sensor, engine speed by an engine speed sensor, clutch stroke by a clutch stroke sensor, and automobile speed by an autornobile speed sensor to generate sensor data;
3b LZ~ 70 (b) cc"paring the sensor data .ith predeter-mined stored data and calculating a c~utch moving time znd a clutch movinq speed, based on the predetermined stored data, for various driving conditions;
(c) controlling at least one of opening and closing of solenoid valves base~ on signals generated from flip-flop circuits via counters activated by said calculating in step (b); and (d) controlling the clutch moving speed and time by means of a clutch actuator controlled by the solenoid valves, using one of a set of pre~etermined constant values corresponding to a selected one of parameters of driving conditions from clutch slip to near clutch engagement and then using a preaetermined constant speed to clutch engagement.
:
; Yet another embodiment of the present invention provides a method of automatic clutch control for automobiles, using a microcomputer and comprising the steps of:
~ (a) detecting accelerator position by an accelerator pedal sensor, engine speed by an engine speed sensor, clutch stroke by a clutch stroke sensor, and automobile speed by an automobile speed sensor to generate sensor data;
(b) comparing the senso-r data with predeter-mined stored data and calculating a clutch rno~7ing time and a clutch moving speed, based on the predeterrnined stored data, for various driving conditions;
: 3c ~`~' . ' .
~Z~7(1 70 (c) cGntrollir,c at ledst one of o?ening and closing of solenoid valves based on signals generated from flip-flop circuits via counters activated by said calculating in step ~b), two of the solenoid valves being provided in series in a supply side fluid passage and another two of the solenoid valves being pl-ovided in parallel in an e~haust side fluid passage, a auantity of fluid flow being controlled by overlapping timing of the at least one of opening and closing of the solenoid valves of both the supply and e~haust sides using the microcomputer; and .
(d) controlling the clutch moving time and clutch moving speed hy means of a c1utch actuator controlled by the solenoid valves.
Yet another aspect of the invention provides an automatic clutch control system for an automobile having an engine with a throttle, an accelerator pedal and a transmission with a clutch, the system comprising~
I
a throttle actuator, coupled to the throttle, for adjustment of the throttle;
a clutch actuator, coupled to the clutch, for controlling engagement and disengagement of the clutch;
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~2~7(;~7~ , solenoid valves, hydraulically connected to said clutch actuator, for controlling the movement of said clutch actuator;
clutch stroke sen~ing means, coupled to said clutch actuator, for sensing clutch stroke;
accelerator sensing means, coupled to the accelerator pedal, for sensing accelerator position;
engine speed sensing means, coupled to : the engine, for sensing engine speed;
automobile speed sensing means, coupled to the transmission, for sensing automobile speed; and control means, operatively connected to said clutch stroke sensing means, said accelerator sensing means, said engine speed sensing means and said automobile speed sensing means, for controlling opening and-closi~ng o~ the solenoïd valves, gear change.of the transmissi.on and adjustments of the throttle actuator, in dependence upon the conditions sensed by said clutch stroke, accelerator, engine speed and automobile speed sensing means, to provide automatic control of clutch moving time.and clutch moving speed.
.
3e 17~7~
The present invention enables easy driving under all driving conditions and improved operability and gas mileage compared with conventional manual, semiautomatic, and Eully automatic transmis-sions. Moreover, it can be used with dry-type single-plate elutches and sliding-mesh-type transmissions used in conventional manual and semiautomatic transmissions.
BRIE~ DESC~IPTICN QF THE DRAWLNGS
In the drawings, Fig. 1 is a schematie bloek diagram of an automatie eluteh control system in a conventional semiautomatie transmission;
Fig. 2 is a partial schematie view of a clutch aetuator shown in Fig. l;
Fig. 3 is a timing ehart of drive current applied to a solenoid valve (A), the quantity of oil flow through one solenoid valve (B)" and the quantity of oil flow through another solenoid valve (C); -~
Fig. 4 is a schematic block diagram of an-automatic clutch control system according to the present invention;
Fig. 5 is a schematic block diagram of a hydraulic control circuit including the solenoid valves controlled by the -i rontroller -hohn in Fig. 4 3f 1~L7(~7~) Fig. 6 is a schematic block diagram for explaining the automatic clutch control system shown in Fig. 4;
Fig. 7 to Fig. 9 are graphs for explaining relations between - clutch stroke and clutch moving time (Fig. 7) and between clutch stroke and clutch moving speed (Fig. 8 and Fig. 9);
Fig. lO shows timing charts for opening and closing of valves and the quantity of fluid flow therethrough;
Fig. ll is a basic block diagram of the controller shown in Fig. 4; and lOFig. 12 is a flow chart of clutch control procedure performed in the controller shown in Fig. ll.
DESCRIPTIGN Q~ THE PREE~RRED EMBODIM~NIS
In general, rotation of an automobile engine is transmitted to the shaft of a transmission mechanism by a dry-type single-plate clutch. To control the clutch engagement, a hydrauliccontrol actuator is used. The hydraulic control actuator is constituted by a hydraulic cylinder used to engage and disengage the clutch and a plurality of solenoid valves used to control the motion of the hydraulic cylinder. Control of the hydraulic actuator, i.e., control of the solenoid valves, is effected mechanically in manual transmissions and electronically in semiautomatic transmissions.
Before describing the preferred embodiments of the present invention, an explanation will be given of a conventional clutch control system for a semiautomatic transmission using a dry-type single-plate clutch and hydraulic control actuator.
Referring to Fig. l, reference numeral l is an accelerator pedal, lA an accelerator pedal sensor, 2 an engine, 2A an engine speed sensor, 3 a throttle actuator, 4 a clutch, 5 a transmis-sion, 6 a clutch actuator, 6A a clutch stroke sensor, 7 asolenoid valve group, 8 an oil pump, 9 an oil tank, lO a control unit, and ll an automobile speed sensor.
The control unit lO, constituted by a microcomputer, con-91 217C~
trols the throttle actuator 3 and the solenoid valve group 7based on a signal transmitte~ from the accelerator pedal sensor lA, a signal transmitted from the engine speed sensor 2A, a signal transmitted from the clutch stroke sensor 6A, and a signal transmitted from the automobile speed sensor 11. The control unit 10 also feeds back the stroke signal transmitted from the clutch stroke sensor 6A to control the opening of the solenoid valve group 7 for engagement, slip, or disengagement of the clutch based on the clutch moving speed, as defined by clutch engagement, clutch slip, clutch disengagement, change in engine speed, automobile speed, and other driving conditions.
In other clutch control systems used for semiautomatic transmission, the system feeds back a stroke signal transmitted from a clutch stroke sensor, engine speed sensor, and automobile speed sensor to control the duty ratio (ratio of opening and closing time of valve) of solenoid valves by a control unit so as to obtain both a clutch moving speed and clutch moving time defined by engine speed, automobile speed, and other driving conditions.
However, it is difficult to obtain the desired clutch moving speed and clutch moving time by controlling the opening or closing of the solenoid valves because it is necessary to finely control the duty ratio of the opening or closing of the valves, which necessitates complex valve control.
The above problems will be explained in detail hereinafter with respect to Fig. 2 and Fig. 3. Referring to Fig. 2, as mentioned above, the hydraulic control actuator is constituted by a clutch actuator, i.e., an oil cylinder 6, and a plurality of solenoid valves (Vl to V3). A piston 6B equipped with a piston rod 6C is provided in the oil cylinder 6. The solenoid valve Vl is provided for exhaust in a small diameter fluid passage, and the solenoid valve V2 is provided for exhaust in a large diameter fluid passage. The solenoid valve V3 is provided for supply.
~L'7~7~
Although only two exhaust solenoid valves Vl and V2 are shown in the drawing, generally a plurality of fluid passages having the same diameters are provided in the actuator and each fluid passage is controlled by a solenoid valve. In the case shown in the drawing, the solenoid valve V2 is used for coarse control of the oil flow, and solenoid valve Vl for fine control of the oil flow.
Referring to Fig. 3, when a drive cnrrent having a pulse waveform as shown in ~A) is applied to the solenoid valves Vl and V2, the oil flow through the solenoid valve Vl in the small diameter fluid passage is shown by (B), and the oil flow through the solenoid valve V2 in the large diameter fluid passage is shown by (C).
The oil flows through the solenoid valves Vl and V2 are constant so long as the pulse waveform of the drive current is the same, i.e., has the same pulse width. The oil flow, however, changes when the pulse width becomes smaller or along with increasingly smaller diameters of fluid passages, in order to achieve finer control, whereby the control of the hydraulic actuator becomes unstable. Acco~dingly, it is difficult to obtain precise control of opening or closing of solenoid valves so as to obtain the desired clutch moving speed and clutch moving time~
An automatic clutch control system according to the present invention will now be explained in detail. As explained above, the automatic clutch control system according to the present invention can be used with conventional dry-type single-plate clutches and sliding-mesh-type transmissions. In the present invention, the change lever used in semiautomatic transmissions is eliminated and a transmission changer (drive mechanism) added instead. These clutch and drive mechanisms are controlled by a microcomputer controller~ Accordingly, the clutch control system according to the present invention is a fully automatic ~Z1707V
.
transmission using a conventional clutch and transmission.
~ eferring to Fig. ~, the automatic clutch control system is constituted by the same comFonents as shown in Fig. 1, except for a controller 100, a solenoid valve group 70, and a changer 12.
Components the same as in Fig. 1 are indicated by the same reference numerals.
Referring to Fig. 5, the clutch 4 is constituted by a clutch pressure plate 4A, clutch disk 4B, diaphragm spring qC, clutch release bearing 4D, clutch release lever 4E, clutch shaft 4F, and lever 4G. Reference numeral 2B is an engine flywheel; 701, 701', 702, and 703 solenoid valves in the solenoid qroup 70; B a battery; SW a power switch associated with an ignition switch;
and AC an accumulator.
The clutch 4 is controlled by controlling the opening or 15 closing of the solenoid valves 701, 701', 702, and 703 using the controller 100. The controller 100 consists of a microcomputer storing a program with respect to driving conditions. When the solenoid valves 701 and 701', for example, are actuated by the controller 100, pressurized fluid is supplied to the oil cylinder 6 from the oil pump 8. The piston 5B of the oil cylinder 6 is thus moved toward the right as indicated by the arrow line to disengage the clutch disk 4B. When the solenoid valves 702 and 703 are actuated by the controller 100, the pressurized fluid is exhausted from the oil cylinder 6. The piston 6B thus moves in the reverse direction due to the action of a return spring (not shown) to re-engage the clutch disk ~B.
This control of clutch engagcment and disengagement ~ill be explained in more detail hereinafter with respect to Figs. 6, 7, 8, 9, and 10.
The controller 100 stores various parameters, for example, a to d shown in Figs. 7 to 9, defining the relation between the clutch stroke and clutch moving time or between the clutch stroke and clutch moving speed based on various driving conditionst 9LZ~7~7~
such as upward or downward slopes, flat roads, and stopping. The controller 100 uses these parameters a to d and the signal transmitted from the clutch stroke sensor 6A, for example, a potentiometer, to calculate the desireable clutch moving speed and clutch moving time corresponding to the clutch stroke S and controls the solenoid valve group 70 based on the results of its calculations.
The control modes will be explained in more detail with respect to Figs. 7 to 9. Referring to Fig. 7, the ordinate indicates the clutch stroke (S) and the abscissa indicates the clutch moving time (T). The lines I, II, and III indicate clutch engagement (clutch on), clutch slip (half clutch), and clutch disengagement (clutch off). As is obvious from the graph, the clutch moving time is controlled to a predetermined gradually increasing value in the clutch operation from line III to line II
and controlled to one of a set of predetermined gradually increasing values corresponding to a selected one of the driving condition parameters a to d in the clutch operation from line II
to line I.
In Figs. 8 and 9, the ordinates indicate the clutch stroke (S) and the abscissas indicate the clutch moving speed (V). In the control modes of both Figs. 8 and 9, the clutch moving speed is controlled to a constant value in the clutch operation from line III to line II. In Fig. 8, the clutch moving speed is controlled to one of a set of predetermined gradually decreasing values corresponding to a selected one of the driving condition parameters a to d in the clutch operation from line II to line I.
In Fig. 9, the clutch moving speed is controlled to one of a set of predetermined constant values in the clutch operation from line II to near line I and to a predctermined constant value to line I.
Next, fine control of the solenoid valves 701, 701', 702, and 703 shown in Fig. 5 and Fig. 6 will be explained in reference -~-` lZ~ 7~
to Fig. 10 (A) to (D).
Referring to Fig. 10, as mentioned above, the open ("on") and close (noff") timings of each solenoid valve 701, 701', 702, - and 703 are controlled by the controller 100. The "on" and "off"
timings can be independently selected by the controller 100.
Generally, there is a time delay between the "on" and "off"
timings in different valves. As a result, the quantity of oil flow through the vaives changes gradually at the leading edges and trailing edges of the waveforms shown in Fig. 10.
In the case of two valves, when both valves are turned on nearly simultaneously by drive currents il and i2 and are left on for a long time, the quantity of oil flow Q is indicated by the hatched area in Fig~ 10 (A). When both valves are simultaneously turned on for a short time, the quantity of oil flow Q is as shown in Fig. 10 (B). When the upstream valve is changed from ~onn to "off" and the downstream valve is changed from "off" to "on~ the quantity of oil flow is as shown in Fiq. 10 (C).
As is obvious from the waveform shown in Fig. 10 (D), the overlapping of the "on~ and "off" timing of the valves affects the quantity of oil flow.
The ~ethod for controlling the quantity of oil flow accord-ing to the present invention is particularly advantageous when the solenoid valves 701, 701', 702, and 703 are controlled as shown in Figs. 10 (C) and (D). Now, in the embodiment shown, the solenoid valves 701 and 701' are provided in series in the supply sidc fluid passage, while the solenoid valves 702 and 703 are provided in parallel in the exhaust side fluid passage. In conventional systems using a single solenoid valve in the supply side, the solenoid valve has not been able to operate fast enough in accordance with a rapid succession of ~on" and "off"
instructions. As a result, conventionally, the quantity of oil flow through the valves during "on" and "off" timing has been unstable.
However, according to the present invention, "on" and "off" control of valves can be independently performed by the controller 100. Consequently, it is possible to control the solenoid valves 701, 701', 702, and 703 to operate at exactly the right timings. A stable flow of oil is possible even with an extremely small overlap of time in "on" timing.
Consequently, since the quantity of oil flow through each valve can be finely controlled by the microcomputer, the clutch moving speed and the clutch moving time can be controlled for various driving conditions.
Referring to Fig. 11, the controller 100 is mainly consti-tuted by analog-digital converters ADl to AD4, an address modi-fier AMO, memories Ml to M4, a comparator and calculator CAL, counters CNTl to CNT4, and flip-flop circuits FFl to FF4. The address modifier AMO, comparator and calculator CAL, and coun-ters CNT are incorporated in a central processing unit CPU.
An analog output detected by, for example, the accelerator pedal sensor lA is applied to the analog-digital converter ADl.
An analog output detected by, for example, the clutch stroke sensor 6A is applied to the analog digital converter AD2. The digital outputs from the analog-digital converters ADl and AD2 are applied to the memories Ml and M2, respectively, via the address modifier AMO. The digital outputs designate addresses in the memories (tables) Ml and M2.
Data read out from the tables is supplied to the compara-tor and calculator CAL and appropriately processed. In the mem-ory Ml, the resultant data and the pulse G are applied to the counter CNTl and the flip-flop FFl for presetting the counter CNTl and for setting the flip-flop FFl. When the flip-flop FFl is set, the transistor TRl turns on and the solenoid valve 701 is activated. The counter CNTl sequentially counts down from the preset number using the periodically input pulse T and re-sets the flip-flop FFl when reaching zero, based on a zero de-tecting signal generating from the counter CNTl itself.
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The output "set signal~ of the ~lip-flop FF1 is applied to a base of a transistor TRl, as explained above, the transistor turns on and the solenoid valve 701 is activated. The flip-flop FFl is rese~ based on the zero detecting signal, the tran-sistor TR1 turns off, and the solenoid valve 701 is deacti-vated. Accordingly, the larger the preset number of the coun-ter CNT1, the longer the activating time (on time) of the sole-noid 701. If the gate value which controls output of the mem-ory M1 is stored in another table, for example, memory M2, the clutch moving speed and clutch moving time can be controlled as shown in Figs. 7 to 9.
Referring to Fig. 12, the signals from each sensor, i.e., the accelerator pedal sensor lA, the engine speed sensor 2A, the clutch stroke sensor 6A, and the automobile speed sensor 11, are first applied to the analog-digital converters at step l. These analog signals are converted to digital signals at step 2~ The digital signals transmitted from the analog-digital converters designate addresses in the tables at step 3.
The stored data is read out from the tables and applied to the comparator and calculator CAL at step 4. The comparator and calculator CAL compares the read out data with prestored data ; of driving conditions a, b, c, and d and calculates dif-ferentials for obtaining clutch moving time and clutch moving speed based on commands transmitted from the central processing unit CPU at steps 5 and 6. The resultant data is applied to the counters, which se~uentially count down from preset numbers based on the periodically input pulses at step 7. The flip-flop circuits are reset by other periodically input pulses when the counts become zero at step 8. The outputs of the flip-flop circuits are applied to the bases of the transistors and the transistors turn on. The solenoid valves are activated by the current flowing through the transistors at step 9. Consequent-ly, the cylinder stroke is controlled by the "on" or "off" tim-ing of each valve at step lO. Therefore, the clutch stroke can be suitably controlled for all driving conditions.
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Claims (13)
1. An automatic clutch control apparatus, for use in automobiles which have an accelerator pedal, a clutch actuated via solenoid valves, a throttle actuator on an engine and a transmission having changeable gears, comprising:
accelerator sensing means, coupled to the accelerator pedal, for sensing accelerator pedal position;
engine speed sensing means, coupled to the engine, for sensing engine speed;
clutch stroke sensing means, coupled to the clutch, for sensing clutch stroke;
automobile speed sensing means, coupled to the transmission, for sensing automobile speed; and control means, operatively connected to said accelerator sensing means, said engine speed sensing means, said clutch stroke sensing means and said automobile speed sensing means, for controlling opening and closing of the solenoid valves, the gear change of the transmission and opening and closing of the throttle actuator, based on predetermined stored data and based on the position of the accelerator pedal, engine speed, clutch stroke and automobile speed, for automatic control of clutch moving time and clutch moving speed.
accelerator sensing means, coupled to the accelerator pedal, for sensing accelerator pedal position;
engine speed sensing means, coupled to the engine, for sensing engine speed;
clutch stroke sensing means, coupled to the clutch, for sensing clutch stroke;
automobile speed sensing means, coupled to the transmission, for sensing automobile speed; and control means, operatively connected to said accelerator sensing means, said engine speed sensing means, said clutch stroke sensing means and said automobile speed sensing means, for controlling opening and closing of the solenoid valves, the gear change of the transmission and opening and closing of the throttle actuator, based on predetermined stored data and based on the position of the accelerator pedal, engine speed, clutch stroke and automobile speed, for automatic control of clutch moving time and clutch moving speed.
2. An apparatus as claimed in claim 1, wherein said clutch stroke sensing means comprises a potentio-meter.
3. An apparatus as claimed in claim 1, wherein said control means comprises a microcomputer.
4. A method of automatic clutch control for automobiles, using a microcomputer and comprising the steps of;
(a) detecting accelerator position by an accelerator pedal sensor, engine speed by an engine speed sensor, clutch stroke by a clutch stroke sensor, and automobile speed by an automobile speed sensor to generate sensor data;
(b) comparing the sensor data with predeter-mined stored data and calculating a clutch moving time and a clutch moving speed, based on the predetermined stored data, for various driving conditions;
(c) controlling at least one of opening and closing of solenoid valves based on signals generated from flip-flop circuits via counters activated by said calculating in step (b), two of the solenoid valves being series-connected solenoid valves and a quantity of fluid flow being controlled by overlapping timing of the least one of opening and closing of the series-connected solenoid valves using the microcomputer; and (d) controlling the clutch moving time and clutch moving speed by means of a clutch actuator controlled by the solenoid valves.
(a) detecting accelerator position by an accelerator pedal sensor, engine speed by an engine speed sensor, clutch stroke by a clutch stroke sensor, and automobile speed by an automobile speed sensor to generate sensor data;
(b) comparing the sensor data with predeter-mined stored data and calculating a clutch moving time and a clutch moving speed, based on the predetermined stored data, for various driving conditions;
(c) controlling at least one of opening and closing of solenoid valves based on signals generated from flip-flop circuits via counters activated by said calculating in step (b), two of the solenoid valves being series-connected solenoid valves and a quantity of fluid flow being controlled by overlapping timing of the least one of opening and closing of the series-connected solenoid valves using the microcomputer; and (d) controlling the clutch moving time and clutch moving speed by means of a clutch actuator controlled by the solenoid valves.
5. A method of automatic clutch control, for automobiles, using a microcomputer, comprising the steps of:
(a) detecting accelerator position by an acclerator pedal sensor, engine speed by an engine speed sensor, clutch stroke by a clutch stroke sensor, and automobile speed by an automobile speed sensor to generate sensor data;
(b) comparing the sensor data with predeter-mind stored data and calculating a clutch moving time and a clutch moving speed, based on the predetermined stored data, for various driving conditions;
(c) controlling at least one of opening and closing of solenoid valves based on signals generated from flip-flop circuits via counters activated by said calculating in step (b); and (d) controlling the clutch moving time and speed by means of a clutch actuator controlled by the solenoid valves, using a predetermined value from clutch disengagement to clutch slip and using one of a set of predetermined values corresponding to a selected one of parameters of driving conditions from clutch slip to clutch engagement.
(a) detecting accelerator position by an acclerator pedal sensor, engine speed by an engine speed sensor, clutch stroke by a clutch stroke sensor, and automobile speed by an automobile speed sensor to generate sensor data;
(b) comparing the sensor data with predeter-mind stored data and calculating a clutch moving time and a clutch moving speed, based on the predetermined stored data, for various driving conditions;
(c) controlling at least one of opening and closing of solenoid valves based on signals generated from flip-flop circuits via counters activated by said calculating in step (b); and (d) controlling the clutch moving time and speed by means of a clutch actuator controlled by the solenoid valves, using a predetermined value from clutch disengagement to clutch slip and using one of a set of predetermined values corresponding to a selected one of parameters of driving conditions from clutch slip to clutch engagement.
6. A method of automatic clutch control for automobiles, using a microcomputer and comprising the steps of:
(a) detecting accelerator position by an accelerator pedal sensor, engine speed by an engine speed sensor, clutch stroke by a clutch stroke sensor, and automobile speed by an automobile speed sensor to generate sensor data;
(b) comparing the sensor data with predeter-mined stored data and calculating a clutch moving time and a clutch moving speed, based on the predetermined stored data, for various driving conditions;
(c) controlling at least one of opening and closing of solenoid valves based on signals generated from flip-flop circuits via counters activated by said calculating in step (b); and (d) controlling the clutch moving speed and time by means of a clutch actuator controlled by the solenoid valves, using a constant value from clutch disengagement to clutch slip and using one of a set of predetermined values corresponding to a selected one of parameters of driving conditions from clutch slip to clutch engagement.
(a) detecting accelerator position by an accelerator pedal sensor, engine speed by an engine speed sensor, clutch stroke by a clutch stroke sensor, and automobile speed by an automobile speed sensor to generate sensor data;
(b) comparing the sensor data with predeter-mined stored data and calculating a clutch moving time and a clutch moving speed, based on the predetermined stored data, for various driving conditions;
(c) controlling at least one of opening and closing of solenoid valves based on signals generated from flip-flop circuits via counters activated by said calculating in step (b); and (d) controlling the clutch moving speed and time by means of a clutch actuator controlled by the solenoid valves, using a constant value from clutch disengagement to clutch slip and using one of a set of predetermined values corresponding to a selected one of parameters of driving conditions from clutch slip to clutch engagement.
7. A method of automatic clutch control for automobiles, using a microcomputer and comprising the steps of:
(a) detecting accelerator position by an accelerator pedal sensor, engine speed by an engine speed sensor, clutch stroke by a clutch stroke sensor, and automobile speed by an automobile speed sensor to generate sensor data;
(b) comparing the sensor data with predeter-mined stored data and calculating a clutch moving time and a clutch moving speed, based on the predetermined stored data, for various driving conditions;
(c) controlling at least one of opening and closing of solenoid valves based on signals generated from flip-flop circuits via counters activated by said calculating in step (b); and (d) controlling the clutch moving speed and time by means of a clutch actuator controlled by the solenoid valves, using one of a set of predetermined constant values corresponding to a selected one of parameters of driving conditions from clutch slip to near clutch engagement and then using a predetermined constant speed to clutch engagement.
(a) detecting accelerator position by an accelerator pedal sensor, engine speed by an engine speed sensor, clutch stroke by a clutch stroke sensor, and automobile speed by an automobile speed sensor to generate sensor data;
(b) comparing the sensor data with predeter-mined stored data and calculating a clutch moving time and a clutch moving speed, based on the predetermined stored data, for various driving conditions;
(c) controlling at least one of opening and closing of solenoid valves based on signals generated from flip-flop circuits via counters activated by said calculating in step (b); and (d) controlling the clutch moving speed and time by means of a clutch actuator controlled by the solenoid valves, using one of a set of predetermined constant values corresponding to a selected one of parameters of driving conditions from clutch slip to near clutch engagement and then using a predetermined constant speed to clutch engagement.
8. A method of automatic clutch control for automobiles, using a microcomputer and comprising the steps of:
(a) detecting accelerator position by an accelerator pedal sensor, engine speed by an engine speed sensor, clutch stroke by a clutch stroke sensor, and automobile speed by an automobile speed sensor to generate sensor data;
(b) comparing the sensor data with predeter-mined stored data and calculating a clutch moving time and a clutch moving speed, based on the predetermined stored data, for various driving conditions;
(c) controlling at least one of opening and closing of solenoid valves based on signals generated from flip-flop circuits via counters activated by said calculating in step (b), two of the solenoid valves being provided in series in a supply side fluid passage and another two of the solenoid valves being provided in parallel in an exhaust side fluid passage, a quantity of fluid flow being controlled by overlapping timing of the at least one of opening and closing of the solenoid valves of both the supply and exhaust sides using the microcomputer; and (d) controlling the clutch moving time and clutch moving speed by means of a clutch actuator controlled by the solenoid valves.
(a) detecting accelerator position by an accelerator pedal sensor, engine speed by an engine speed sensor, clutch stroke by a clutch stroke sensor, and automobile speed by an automobile speed sensor to generate sensor data;
(b) comparing the sensor data with predeter-mined stored data and calculating a clutch moving time and a clutch moving speed, based on the predetermined stored data, for various driving conditions;
(c) controlling at least one of opening and closing of solenoid valves based on signals generated from flip-flop circuits via counters activated by said calculating in step (b), two of the solenoid valves being provided in series in a supply side fluid passage and another two of the solenoid valves being provided in parallel in an exhaust side fluid passage, a quantity of fluid flow being controlled by overlapping timing of the at least one of opening and closing of the solenoid valves of both the supply and exhaust sides using the microcomputer; and (d) controlling the clutch moving time and clutch moving speed by means of a clutch actuator controlled by the solenoid valves.
9. A method as claimed in claim 8, wherein step (c) comprises controlling the solenoid valves in the exhaust side fluid passage which has a first diameter and in the supply side fluid passage which has a second diameter different from the first diameter.
10. An automatic clutch control system for an automobile having an engine with a throttle, an accel-erator pedal and a transmission with a clutch, said system comprising:
a throttle actuator, coupled to the throttle, for adjustment of the throttle;
a clutch actuator, coupled to the clutch, for controlling engagement and disengagement of the clutch;
solenoid valves, hydraulically connected to said clutch actuator, for controlling the movement of said clutch actuator;
clutch stroke sensing means, coupled to said clutch actuator, for sensing clutch stroke;
accelerator sensing means, coupled to the accelerator pedal, for sensing accelerator position;
engine speed sensing means, coupled to the engine, for sensing engine speed;
automobile speed sensing means, coupled to the transmission, for sensing automobile speed; and control means, operatively connected to said clutch stroke sensing means, said accelerator sensing means, said engine speed sensing means and said automobile speed sensing means, for controlling opening and closing of the solenoid valves, gear change of the transmission and adjustments of the throttle actuator, in dependence upon the conditions sensed by said clutch stroke, accelerator, engine speed and automobile speed sensing means, to provide automatic control of clutch moving time and clutch moving speed.
a throttle actuator, coupled to the throttle, for adjustment of the throttle;
a clutch actuator, coupled to the clutch, for controlling engagement and disengagement of the clutch;
solenoid valves, hydraulically connected to said clutch actuator, for controlling the movement of said clutch actuator;
clutch stroke sensing means, coupled to said clutch actuator, for sensing clutch stroke;
accelerator sensing means, coupled to the accelerator pedal, for sensing accelerator position;
engine speed sensing means, coupled to the engine, for sensing engine speed;
automobile speed sensing means, coupled to the transmission, for sensing automobile speed; and control means, operatively connected to said clutch stroke sensing means, said accelerator sensing means, said engine speed sensing means and said automobile speed sensing means, for controlling opening and closing of the solenoid valves, gear change of the transmission and adjustments of the throttle actuator, in dependence upon the conditions sensed by said clutch stroke, accelerator, engine speed and automobile speed sensing means, to provide automatic control of clutch moving time and clutch moving speed.
11. An automatic clutch control system as claimed in claim 10, wherein said solenoid valves comprise a first group of at least two solenoid valves hydrauli-cally connected to said clutch actuator in series and controlled by first overlapping timing signals from said control means.
12. An automatic clutch control system as claimed in claim 11, further comprising supply and exhaust fluid passages hydraulically connecting said clutch actuator and said solenoid valves, wherein said first group of at least two solenoid valves is connected to the supply fluid passage, and wherein said solenoid valves further comprise a second group of at least two solenoid valves connected to the exhaust fluid passage in parallel and controlled by second overlapping timing signals from said control means.
13. An automatic clutch control system as claimed in claim 12, wherein said supply fluid passage has a first diameter and said exhaust fluid passage has a second diameter different than the first diameter.
Applications Claiming Priority (6)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58108248A JPS601448A (en) | 1983-06-16 | 1983-06-16 | Clutch controller |
| JP58-108248 | 1983-06-16 | ||
| JP58108247A JPS601402A (en) | 1983-06-16 | 1983-06-16 | Actuator |
| JP58-108247 | 1983-06-16 | ||
| JP58-119165 | 1983-06-30 | ||
| JP58119165A JPS6011721A (en) | 1983-06-30 | 1983-06-30 | Controller for clutch |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1217070A true CA1217070A (en) | 1987-01-27 |
Family
ID=27311184
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000456211A Expired CA1217070A (en) | 1983-06-16 | 1984-06-08 | Automatic clutch control system |
Country Status (5)
| Country | Link |
|---|---|
| KR (1) | KR880001730B1 (en) |
| AU (1) | AU549350B2 (en) |
| CA (1) | CA1217070A (en) |
| DE (1) | DE3480993D1 (en) |
| ES (2) | ES8601498A1 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112879466A (en) * | 2021-01-08 | 2021-06-01 | 大连职业技术学院 | Semi-linkage automatic control mechanism of manual transmission automobile clutch, stroke calculation method and execution steps |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109305036A (en) * | 2018-10-17 | 2019-02-05 | 邢台威力汽车零部件有限公司 | A kind of executing agency not stepping on clutch and putting into gear |
-
1984
- 1984-06-08 CA CA000456211A patent/CA1217070A/en not_active Expired
- 1984-06-14 AU AU29366/84A patent/AU549350B2/en not_active Ceased
- 1984-06-15 ES ES533454A patent/ES8601498A1/en not_active Expired
- 1984-06-15 DE DE8484304033T patent/DE3480993D1/en not_active Expired - Fee Related
- 1984-06-15 KR KR8403373A patent/KR880001730B1/en not_active IP Right Cessation
-
1985
- 1985-05-10 ES ES543021A patent/ES8609064A1/en not_active Expired
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112879466A (en) * | 2021-01-08 | 2021-06-01 | 大连职业技术学院 | Semi-linkage automatic control mechanism of manual transmission automobile clutch, stroke calculation method and execution steps |
| CN112879466B (en) * | 2021-01-08 | 2022-11-08 | 大连职业技术学院 | Semi-linkage automatic control mechanism of manual transmission automobile clutch, stroke calculation method and execution steps |
Also Published As
| Publication number | Publication date |
|---|---|
| ES533454A0 (en) | 1985-10-16 |
| DE3480993D1 (en) | 1990-02-15 |
| ES8609064A1 (en) | 1986-08-01 |
| ES8601498A1 (en) | 1985-10-16 |
| AU2936684A (en) | 1984-12-20 |
| ES543021A0 (en) | 1986-08-01 |
| KR850000319A (en) | 1985-02-26 |
| AU549350B2 (en) | 1986-01-23 |
| KR880001730B1 (en) | 1988-09-10 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry | ||
| MKEX | Expiry |
Effective date: 20040608 |