GB2242495A - Electromagnetic clutch control device for vehicles - Google Patents

Electromagnetic clutch control device for vehicles Download PDF

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Publication number
GB2242495A
GB2242495A GB9106018A GB9106018A GB2242495A GB 2242495 A GB2242495 A GB 2242495A GB 9106018 A GB9106018 A GB 9106018A GB 9106018 A GB9106018 A GB 9106018A GB 2242495 A GB2242495 A GB 2242495A
Authority
GB
United Kingdom
Prior art keywords
clutch
current
reverse energization
control device
electromagnetic clutch
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.)
Granted
Application number
GB9106018A
Other versions
GB9106018D0 (en
GB2242495B (en
Inventor
Fumihiko Nishiwaki
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Mitsubishi Electric Corp
Original Assignee
Mitsubishi Electric Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Mitsubishi Electric Corp filed Critical Mitsubishi Electric Corp
Publication of GB9106018D0 publication Critical patent/GB9106018D0/en
Publication of GB2242495A publication Critical patent/GB2242495A/en
Application granted granted Critical
Publication of GB2242495B publication Critical patent/GB2242495B/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

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Classifications

    • 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
    • F16D48/064—Control of electrically or electromagnetically actuated clutches
    • 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
    • F16D2500/1021—Electrical type
    • F16D2500/1022—Electromagnet
    • 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
    • F16D2500/104—Clutch
    • F16D2500/10406—Clutch position
    • F16D2500/10412—Transmission line of a vehicle
    • 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
    • F16D2500/30—Signal inputs
    • F16D2500/306—Signal inputs from the engine
    • 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
    • F16D2500/30—Signal inputs
    • F16D2500/31—Signal inputs from the vehicle
    • 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
    • F16D2500/30—Signal inputs
    • F16D2500/316—Other signal inputs not covered by the groups above
    • F16D2500/3166—Detection of an elapsed period of time
    • 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
    • F16D2500/70—Details about the implementation of the control system
    • F16D2500/704—Output parameters from the control unit; Target parameters to be controlled
    • F16D2500/70402—Actuator parameters
    • F16D2500/70418—Current
    • 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
    • F16D2500/70—Details about the implementation of the control system
    • F16D2500/704—Output parameters from the control unit; Target parameters to be controlled
    • F16D2500/70422—Clutch parameters
    • F16D2500/70424—Outputting a clutch engaged-disengaged signal
    • 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
    • F16D2500/70—Details about the implementation of the control system
    • F16D2500/71—Actions
    • F16D2500/7107—Others
    • F16D2500/7109—Pulsed signal; Generating or processing pulsed signals; PWM, width modulation, frequency or amplitude modulation

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Electromagnetism (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • Hydraulic Clutches, Magnetic Clutches, Fluid Clutches, And Fluid Joints (AREA)

Abstract

An electromagnetic clutch control device for vehicles, comprises clutch current calculation means (2) for outputting a clutch current command signal (SI) and a clutch disengaging signal (S0) based on running control information (DD) and engine control information (SE); a reverse energization resister (18) arranged between a power source (3) and a clutch coil (41) of an electromagnetic clutch (4) for the vehicle with the control device; clutch current control means (1) for controlling the supply of a clutch current to the electromagnetic clutch (4) based on the clutch current command signal (SI) and the clutch disengaging signal (S0), the clutch current control means (1) including the reverse energization resister (18); and switching means (22) which is subjected to the on and off control by the clutch current calculation means (2), and which is arranged to be in series with the reverse energization resister (18); wherein the switching means (22) is in the form of a reverse energization transistor to which a signal (SR) is supplied for only a predetermined period when means (2) determines the clutch should be disengaged, thereby allowing a minute reverse current to flow in the reverse energization resister (18). <IMAGE>

Description

ELECTROMAGNETIC CLUTCH CONTROL DEVICE FOR VEHICLES The present invention relates to an electromagnetic clutch control device for vehicles which controls the engagement and disengagement of a vehicle electromagnetic clutch.
Referring to Figure 3, there is shown a block diagram showing the structure of a conventional vehicle electromagnetic clutch control device which is disclosed in e.g. Japanese Unexamined Patent Publications Nos.
1431/1985 and 57342/1988.
In Figure 3, reference numeral 1 designates clutch current control means. Reference numeral 2 designates clutch current calculation means such as a micro computer. Reference numeral 3 designates a battery which is mounted on a vehicle. Reference numeral 4 designates an electromagnetic clutch.
The clutch current calculation means 2 outputs a clutch current command signal SI,t which is in turn inputted into the positive input terminal of a current deviation amplifier 14 which is arranged in the clutch current control means 1. The clutch current calculation means also outputs an engagement signal So, which is in turn supplied to the base of â transistor 12 at a negative side as output transistor, which is arranged in the clutch current control means 1.
The negative side transistor 12 has the emitter connected to the negative pole of the battery 3 and to ground through a clutch current detection resistor 13.
The emitter of the negative side transistor 12 is to output a current feedback signal SF to the negative input terminal of the current deviation amplifier 14.
The current deviation amplifier 14 calculates the difference between the clutch current command signal SI and the current feedback signal SF. The result of calculation is suppl ed, through a pulse width modulator (hereinbelow, referred to as PWM 15), to the base of a transistor 11 at a positive side as output transistor in the clutch current control means 1. This arrangement controls the on and off operation of the positive side transistor 11.
The positive side transistor 11 has the emitter is connected to the positive pole of the battery 3. The positive side transistor 11 has the collector grounded through a parallel circuit of a free wheeling diode 16 and a reverse energization resistor 18, and also connected to an output terminal 20 of the clutch current control means 1.
The negative side transistor 12 has the collecter connected to the positive pole of the battery 3 through a parallel circuit of a reverse energization resistor 19 and an overvoltage prevention diode 17, and also connected to an output terminal 21 of the clutch current control means 1.
The reverse energization resistors 18 and 19 are to flow a minute reverse energizing current through the electromagnetic clutch 4 when both positive side transistor 11 and negative side transistor 12 are off.
The output terminals 20 and 21 are output terminals of the clutch current control means 1, and are connected to slip rings 42 and 42 of the electromagnetic clutch 4, respectively.
The electromagnetic clutch 4 is constituted by a clutch coil 41, and the two slip rings 42 and 42 connected in series with the clutch coil 41.
To the clutch current calculation means 2 are inputted running control information SD and engine control information SE.
Now, the operation of the conventional electromagnetic clutch control device will be explained.
The clutch current calculation means 2 calculates vehicle speed, and then calculates engine speed. In addition, the clutch current calculation means 2 receives the running control information SD and the engine control information SEr and calculates a clutch torque based on these information. The clutch current calculation means 2 outputs a clutch current which corresponds to the calculated clutch torque.
When the electromagnetic clutch is disengaged, the output from the PWM 15, and the clutch disengagement signal So from the clutch current calculation means 2 causes the positive side transistor 11 and the negative side transistor 12 to be off, respectively.
As a result, the minute reverse energization current flows in the electromagnetic clutch 4 through the reverse energization resistors 18 and 19.
When the electromagnetic clutch 4 is engaged, the clutch current is detected by the clutch current detection resistor 13. In that time, the negative side transistor 12 remains on.
The current feedback signal SF which is indicative of a feedback value of the clutch current detected by the clutch current detection resistor 13 is inputted to the negative input terminal of the current deviation amplifier 14. To the positive input terminal of the current deviation amplifier 14 is inputted the clutch current command signal SI from the clutch current calculation means 2.
The current deviation amplifier 14 compares the current feedback signal SF with the clutch current command signal SI to find the deviation therebetween, and outputs the deviation to the PWM 15.
The PWM 15 gives pulse width modulation to the output from-the current deviation amplifier 14, and inputs the modulated signal to the base of the positive side transistor 11. As a result, the positive side transistor 11 carries out the on and off operation depending on the pulse width of the output from the PWM 15. In this manner, the clutch current to the electromagnetic clutch 4 is controlled. When the PWM 15 is on, the current flows through the reverse energization resistor 18 too.
The free wheeling diode 16 has a free wheeling current flowed therethrough when the positive side transistor 11 is off.
Because the conventional vehicle electromagnetic clutch control device is constructed as stated earlier, voltages are constantly applied across the reverse energization resistors 18 and 19, respectively, in feeding power to the clutch, regardless of whether it is the time to feed the minute reverse energization current.
As a result, power loss is increased to cause the resistors to be heated to a high temperature. In order to cope with this, the reverse energization resistor 18 has to be prepared in the form of a large power element having a great size, creating a problem in that reliability will deteriorate with time.
It is an object of the present invention to dissolve the problem, and to provide a vehicle electromagnetic clutch control device capable of decreasing power loss, of minimizing the size and of maintaining reliability by limiting the time to flow a current in the reverse energization resistor in a certain period from the disengagement of an electromagnetic clutch.
The forgoing and other objects of the present invention have been attained by providing an electromagnetic control device for vehicles, comprising clutch current calculation means for outputting a clutch current command signal and a clutch disengaging signal based on running control information and engine control information; a reverse energization resistor arranged between a power source and a clutch coil of an electromagnetic clutch for the vehicle with the control device; clutch current control means for controlling the supply of a clutch current to the electromagnetic clutch based on the clutch current command signal and the clutch disengaging signal, the clutch current control means including the reverse energization resistor; and switching means which is subjected to the on and off control by the clutch current calculation means, and which is arranged to be in series with the reverse energization resistor; wherein the switching means is being on for a predetermined period since the clutch disengaging signal was outputted, thereby allowing a minute reverse current to flow in the reverse energization resistor.
The vehicle electromagnetic control device according to the present invention has such structure that the switching means is turned on only for the predetermined period since the electromagnetic clutch was disengaged, allowing the minute reverse energization current to flow in the reverse energization resistor only for that period, and to prevent the reverse energization resistor from being energized in other times.
The present invention allows the reverse energization resistor to have a small power capacity and to be minimized. In addition, the present invention can eliminate waste power consumption, and can minimize an increase in temperature. As a result, it is provided an advantage in that reliability will not deteriorate with time.
In drawings: Figure 1 is a schematic diagram showing an embodiment of the vehicle electromagnetic clutch control device according to the present invention; Figure 2 is a flow chart showing the operations of the clutch current calculation means shown in Figure 1; and Figure 3 is a schematic diagram showing a conventional electromagnetic clutch control device.
Now, the present invention will be described in detail with reference to a preferred embodiment illustrated in the accompanying drawings. Figure 1 is a schematic diagram showing the structure of the embodiment of the control device according to the present invention.
In Figure 1, like reference numerals indicate parts identical or corresponding to those shown in Figure 3, and explanation of these parts will be omitted for the sake of simplicity. Parts different from those shown in Figure 3 will be mainly described.
The embodiment of Figure 1 is different from the conventional device of Figure 3 in that another reverse energization transistor 22 is provided between a reverse energization resistor 18 and ground in the form of common-emitter connection. The reverse energization transistor 22 has the collecter connected to a positive side transistor 11 through the reverse energization resistor 18. The reverse energization transistor 22 has the base connected t an output port of a clutch current calculation means 2.
Now, the operations of the embodiment will be explained though the explanation on the operations which overlaps with that of the conventional device shown in Figure 3 will be omitted for the sake of simplicity.
When an electromagnetic clutch 4 is energized to be engaged, a clutch reverse energization signal SR which provides power to the base of the reverse energization transistor 22 is held zero by the clutch current calculation means 2, causing the reverse energization transistor 22 to be held off. As a result, no current flow through the-reverse energization resistor 18 to eliminate waste power consumption.
When the clutch is disengaged, the clutch current calculation means 2 is supplying the clutch reverse energization signal SR to the base of the reverse energization transistor 22 for only a predetermined period from the moment when the clutch current calculation means 2 judged that it was the time to disengage the clutch. In this manner, the reverse energization transistor 22 is held on only for that period. A minute reverse energization current flows through the reverse energization resistor 18 and a reverse energization resistor 19 only for the predetermined period where the reverse energization transistor 22 is held on. After the predetermined period has passed, the clutch current calculation means 2 cut off the reverse energization transistor 22 to prevent the minute reverse energization current from flowing thereafter.
The main operations of the clutch current calculation means 2 will be described in reference to the flow chart of Figure 2. At Step 101, whether the clutch is to be disengaged or not is judged based on engine control information SE and running control information SD. For example, whether a variable speed range switch signal which can be obtained based on the engine control information SE and the running control information SD is in the parking range or the neutral range of a transmission is judged. If the clutch is not to be disengaged, the program proceeds to Step 102 where a clutch current which corresponds to a clutch torque for engaging the clutch is outputted to take an energizing mode. At that time, the reverse energization transistor 22 is held off.
If it is judged at Step 101 that the clutch is to be disengaged, the program proceeds to Step 103. At Step 103, whether the predetermined period has continuously passed since the moment when it was judged that the clutch should be disengaged. Such judgment can be made e.g. by reading the count of a timer which becomes down to 0 when the predetermined period has passed, and finding whether the count is 0 or not. If the predetermined period has not passed, the program proceeds to Step 104 where the reverse energization transistor 22 is turned on to take a reverse energization mode. If the predetermined period or longer has passed, the program proceeds to Step 105 where the reverse energization transistor 22 is turned off to take zero current mode.
When one of Steps 102, 104 and 105 has been completed, the program finishes one unit of operations.
Such operations are repeated to carry out the on and off control for the reverse energization transistor 22.
For example, suppose that the reverse energization resistors 18 and 19 have a resistance of 100 Q and that the output voltage of a battery 3 which is mounted to a vehicle is 12 V. In the case of the conventional control device, about 120 mA of current flows in the reverse energization resistor 18 on feeding power to the clutch.
On the other hand, the current which flows through the reverse energization resistor 18 is 0 in the embodiment.
Suppose that the impedance of a clutch coil 41 is 1-2 Q on disengaging the clutch, the minute reverse energization current which flows through the reverse energization resistor 18 is about 60 mA, and the minute reverse energization current is flowing only for the certain period in the embodiment. As a result, this shows that the reverse energization resistor 18 in the embodiment is sufficient to have a fourth the power capacity of the reverse energization resistor in the conventional control device.

Claims (6)

CLAIMS:
1. An electromagnetic clutch control device for vehicles, comprising: clutch current calculation means for outputting a clutch current command signal and a clutch disengaging signal based on running control information and engine control information a reverse energization resistor arranged between a power source and a clutch coil of an electromagnetic clutch for the vehicle with the control device; clutch current control means for controlling the supply of a clutch current to the electromagnetic clutch based on the clutch current command signal and the clutch disengaging signal , the clutch current control means including the reverse energization resistor ; and switching means which is subjected to the on and off control by the clutch current calculation means and which is arranged to be in series with the reverse energization resistor wherein the switching means is being on for a predetermined period since the clutch disengaging signal was outputted, thereby allowing a minute reverse current to flow in the reverse energization resistor
2. An electromagnetic clutch control device according to Claim 1, wherein the switching means comprises a transistor.
3. An electromagnetic clutch control device according to Claim 2, wherein the transistor is connected between the reverse energization resistor and ground.
4. An electromagnetic clutch control device according to Claim 3, wherein the transistor has common-emitter connection.
5. An electromagnetic clutch control device according to Claim 3, wherein the transistor has the base connected to an output port of the clutch current calculation means
6. An electromagnetic clutch control device for vehicles, substantially as herein described with reference to Figures 1 and 2 of the accompanying drawings.
GB9106018A 1990-03-23 1991-03-21 Electromagnetic clutch control device for vehicles Expired - Fee Related GB2242495B (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2075110A JPH03277829A (en) 1990-03-23 1990-03-23 Control device of electromagnetic clutch for vehicle

Publications (3)

Publication Number Publication Date
GB9106018D0 GB9106018D0 (en) 1991-05-08
GB2242495A true GB2242495A (en) 1991-10-02
GB2242495B GB2242495B (en) 1994-01-19

Family

ID=13566708

Family Applications (1)

Application Number Title Priority Date Filing Date
GB9106018A Expired - Fee Related GB2242495B (en) 1990-03-23 1991-03-21 Electromagnetic clutch control device for vehicles

Country Status (2)

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JP (1) JPH03277829A (en)
GB (1) GB2242495B (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4571550B2 (en) * 2005-07-20 2010-10-27 富士機工株式会社 Vehicle steering system

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2233420A (en) * 1989-06-30 1991-01-09 Mitsubishi Electric Corp A short-circuit and ground fault detecting apparatus for automotive electromagnetic clutches
GB2233419A (en) * 1989-06-27 1991-01-09 Mitsubishi Electric Corp Temperature detecting device for a vehicular electromagnetic clutch
GB2233729A (en) * 1989-06-27 1991-01-16 Mitsubishi Electric Corp Temperature detection device for electromagnetic clutch of vehicle

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2233419A (en) * 1989-06-27 1991-01-09 Mitsubishi Electric Corp Temperature detecting device for a vehicular electromagnetic clutch
GB2233729A (en) * 1989-06-27 1991-01-16 Mitsubishi Electric Corp Temperature detection device for electromagnetic clutch of vehicle
GB2233420A (en) * 1989-06-30 1991-01-09 Mitsubishi Electric Corp A short-circuit and ground fault detecting apparatus for automotive electromagnetic clutches

Also Published As

Publication number Publication date
JPH03277829A (en) 1991-12-09
GB9106018D0 (en) 1991-05-08
GB2242495B (en) 1994-01-19

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Legal Events

Date Code Title Description
PCNP Patent ceased through non-payment of renewal fee

Effective date: 20090321