JPS6323014B2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a control device for an electromagnetic clutch for a vehicle, and in particular, it is capable of controlling the amount and time of energization to the coil of an electromagnetic clutch, thereby alleviating shock during gear shifting, and when shifting gears in an accelerated state. The present invention relates to a control device for an electromagnetic clutch for a vehicle, which can reduce clutch slippage.

[Conventional technology]

In an electromagnetic clutch for a vehicle, the driven member on the input side of the transmission is closely fitted to the drive member on the crankshaft side, which has a built-in coil, through an extremely small gap, and the clutch current is passed through the coil to connect the drive member to the drive member. The system excites the clutch and concentrates the lines of magnetic force in the gap between it and the driven member to restrain it and transmit the engine power to the input side of the transmission, and then cuts off the clutch current and time to release the constraint caused by the lines of magnetic force in the gap. The clutch current is changed to cause slippage between the drive member and the driven member.
This slippage is used to start the vehicle without the need for clutch pedal operation, which facilitates driving operations, and is already known as a publicly known technique. In addition, as an automated version of the friction plate type manual clutch, Japanese Patent Laid-Open Publication No. 52-27127 and Japanese Patent Laid-Open No.
There is a publication No. 55-76224.

[Problems to be solved by the invention]

In the above-mentioned electromagnetic clutch, if the meshing of the gears of the transmission is changed and the clutch is directly connected when the clutch is re-engaged, the shock becomes large and causes discomfort to the driver.
In conventional control devices, a current smaller than the specified current is passed through the coil of the clutch for a predetermined period of time after the gear shift is completed, and the clutch is directly connected after the clutch is in a half-clutch state, thereby eliminating the shock during gear shifting described above. However, in this conventional control method, the clutch current and its control time for half-clutching are fixed,
It was not possible to change it depending on the operating situation of the vehicle. For this reason, if the gears are being shifted slowly, there will be no shock caused by shifting and the gears will be engaged comfortably, but if the gears are being shifted while depressing the accelerator for sudden acceleration, the clutch current will increase due to the half-clutching. If the clutch was too low, the clutch would slip, and the engine torque would not be immediately transmitted to the axle, causing a slipping sensation in the clutch and making it difficult to respond to driving sensations (the clutch current for half-clutching would be lower than usual). (It is set to correspond to the speed change operation). In view of the above-mentioned drawbacks, the present invention detects and judges the operational status of the vehicle during gear shifting, controls the clutch current so as to change the amount of current for half-clutching, and reduces clutch slippage during acceleration. The present invention provides a control device for an electromagnetic clutch for a vehicle that can perform the following functions.

[Means to solve the problem]

In order to achieve the above object, the present invention provides that a crankshaft is integrally connected to a drive member having a built-in coil through a drive plate, and a driven member of a transmission input shaft is brought close to the drive member through a gap. inputting into the control circuit a gear shift signal output based on the operation of the shift lever of the transmission and a clutch hold signal output based on the acceleration or deceleration state of the vehicle;
In an electromagnetic clutch for a vehicle that transmits power by supplying clutch current from the control circuit to the coil and integrally restraining the drive and driven member by electromagnetic force, the acceleration or deceleration state of the vehicle is detected. The control circuit includes a charging circuit that inputs the speed change signal and outputs a zero level signal when the shift lever is operated, and a clutch hold signal that outputs a signal when the vehicle is decelerated or accelerated. a first reference voltage generation circuit that outputs a predetermined comparison reference voltage; a first comparator that compares and detects an output signal from the charging circuit and an output signal from the first reference voltage generation circuit; a second reference voltage generation circuit that outputs a comparison reference voltage based on the clutch hold signal;
a triangular wave oscillation circuit that outputs a triangular wave signal; a second comparator that compares the output signal from the second reference voltage generation circuit with the output signal from the triangular wave oscillation circuit; and a switching circuit for controlling the current of the first and second comparators, the detection means detects the acceleration state of the vehicle, and the output signals from the first and second comparators are determined based on the shift signal and the clutch hold signal. Therefore, the electromagnetic clutch is configured to control the amount of current and the duration of the current flowing to the coil.

【Example】

An embodiment of the present invention will be described below with reference to the drawings. In this embodiment, the present invention will be explained by embodying an electromagnetic powder clutch, which is a type of electromagnetic clutch. In Figures 1 and 2, the electromagnetic powder clutch assembled into the transaxle type transmission will be explained in detail. Reference numeral 1 is the electromagnetic powder clutch, 2 is the 4-speed forward transmission, and 3 is the electromagnetic powder clutch. is the final gearbox. In the electromagnetic powder type clutch 1, a drive member 8 containing a built-in coil 7 is integrally connected to a crankshaft 5 from the engine via a drive plate 6 within a clutch case with a sealed structure. 10 are spline-fitted so as to be integrated in the rotational direction, and are closely fitted to the drive member 8 via a gap 11, and electromagnetic powder from the powder chamber 12 is accumulated in this gap 11. Further, a gear 13 is integrally connected to the drive member 8, and its cylindrical end is loosely fitted to the input shaft 9, and a slip ring 14 is inserted therein.
is attached, and a lead wire X is connected between the slip ring 14 and the drive member 8, and the slip ring 14 has a brush 16 connected to the lead wire Y, as detailed in FIG. It is held by a holder 17 and is in sliding contact with the coil 7 to supply power. With this configuration, the drive plate 6 and the drive member 8 rotate together with the crankshaft 5, and the electromagnetic powder sealed in the powder chamber 12 is appropriately gathered toward the inner peripheral surface of the drive member 8 by centrifugal force. There is. Therefore, from the lead wire Y to the brush 16,
When power is supplied to the coil 7 via the slip ring 14 and the lead wire X, the excitation of the drive member 8 generates lines of magnetic force around the driven member 10 as shown by the arrow, so that electromagnetic particles accumulate in the gap 11. The drive member 8 and the driven member 10 are integrated, and the engine power of the crankshaft 5 is transmitted to the input shaft 9. Next, in the transmission 2, first to fourth speed drive gears 18 to 21 are integrally provided to an input shaft 9 from the clutch 1, and an output shaft 22 is arranged parallel to the input shaft 9. There is a driven gear 2 in constant mesh with each of the above gears 18 to 21.
3 to 26 are rotatably fitted, two adjacent driven gears 23 and 24 are connected to the output shaft 22 by a synchronization mechanism 27, and driven gears 25 and 26 are connected to the output shaft 22 by another synchronization mechanism 28. Furthermore, a gear mechanism 29 for reversing is provided between the input and output shafts 9 and 22. In this way, by operating the change lever, the synchronizer 27
By integrally connecting the driven gear 23 to the output shaft 22, the power of the input shaft 9 is reduced in amount by the gears 18 and 23 and taken out to the output shaft 22 to obtain the first speed. will be held. Further, an output gear 30 is provided at the end of the output shaft 22.
is provided and meshes with the ring gear 32 in the differential device 31 of the final reduction gear 3, so that the power of the output shaft 22 of the transmission 2 is immediately transferred from the ring gear 32 to the side gear via the case 33, spider 34, and pinion 35. 36 and further transmitted to the drive wheels via the axle 37. Figure 3 shows the configuration of the control circuit, and the input signal system includes a shift signal a generated when the shift switch is turned on when the shift lever (not shown) is operated, and a shift signal a generated when the gear shift switch is turned on when the shift lever (not shown) is operated. It consists of a clutch hold signal b that is generated by turning on a clutch hold switch (described later) when the clutch is depressed more than 3 degrees, and a vehicle speed signal c that detects the set speed by a vehicle speed sensor (not shown).These signals are judged to generate a clutch control signal. can be output. gear shift signal a
is applied to the base of a transistor 41 via an inverter 40, the emitter of the transistor 41 is grounded, and the collector is connected to a charging circuit 44 consisting of a resistor 42 and a capacitor 43. The clutch hold signal b is applied to the base of a transistor 46 via an inverter 45, the collector of the transistor 46 is connected to a resistor 48 via a resistor 47, and the other end of the resistor 48 is grounded. A positive potential is applied to the emitter 46, and a resistor 49 is interposed between the positive potential and the resistor 48. These transistor 46 and resistors 47 to 49 form a reference voltage generation circuit 50. Both outputs of the charging circuit 44 and the reference voltage generation circuit 50 are connected to respective input terminals of a comparator 51, and the output of the comparator 51 is connected to an AND gate 52 and a NAND gate 53 of the switching circuit. A vehicle speed signal c is connected to the other input terminal. Both outputs of the AND gate 52 and the NAND gate 53 are connected to the NAND gate 54.
The output of is connected to an AND gate 55, and the other input terminal of the AND gate 55 is connected to a speed change signal a. The output of the AND gate 55 is connected to the base of a transistor 56, the emitter of the transistor 56 is grounded, and the collector is connected to one end of the coil 7. And coil 7
A commutation circuit 5 consisting of a diode and a resistor is installed at both ends of the
7 is connected. The output of the inverter 45 is connected to the base of a transistor 59 via an inverter 58, and resistors 60 and 61 are connected in series to the collector of the transistor 59, with the resistor 61 being grounded. A positive potential is applied to the emitter of the transistor 59, and the positive potential and the resistor 61
A resistor 62 is interposed between them, and a reference voltage generating circuit 63 is formed by the transistor 59 and the resistors 60 to 62. Further, 64 is a triangular wave oscillation circuit formed of an operational amplifier (operational amplifier), a resistor, etc., and the outputs of the aforementioned reference voltage generation circuit 63 and triangular wave oscillation circuit 64 are connected to each input terminal of a comparator 65, respectively. The output of the comparator 65 is connected to the other input terminal of the NAND gate 53. Next, FIG. 4 shows the vicinity of the accelerator mechanism, and the bracket 70 fixed to the vehicle body is formed by bending thin sheet metal.
A support shaft 71 is rotatably supported on the support shaft 7.
A U-shaped arm 72 is fixed to 1.
An accelerator pedal 73 is attached to the tip of the arm 72. Further, as detection means for detecting acceleration and deceleration states, a pair of cams 74 and 75 are fixed at the center of the support shaft 71 at a distance, and a pair of cams 74 and 75 are fixed to the support rod 76 fixed in the bracket 70. An accelerator switch 77 and a clutch hold switch 78 are opposed to the cams 74 and 75, respectively. This arm 72 is always biased clockwise in the figure by a spring (not shown), and is rotated counterclockwise by pressing the accelerator pedal 73 with the foot. In FIG. 4, the accelerator pedal 73 is in the normal stopped position shown by , and the accelerator pedal 73 is not depressed. At the position where the accelerator pedal 73 is slightly depressed, the cam 74 pushes the accelerator switch 77 to turn on the accelerator switch 77, and when the accelerator pedal 77 is further depressed, the cam 74 moves about 1/4 to 1/3 of the entire stroke. Cam 75 in the position shown in the figure
presses the clutch hold switch 78 to turn the clutch hold switch 78 on. Next, the operation of this embodiment will be explained with reference to the timing chart of FIG. The shift signal a is a signal that changes to low level only when shifting while operating the shift lever, and the clutch hold signal b is a signal that turns on the clutch hold switch 78 when the accelerator pedal is depressed by 1/4 to 1/3 or more. The vehicle speed signal c is a signal that changes from high level to low level depending on the vehicle speed, e.g.
This signal becomes high level when the speed is 15m/h or more. If the accelerator pedal is pressed less than 1/4 to 1/3 of the entire stroke (deceleration or slow acceleration) after shifting at a set vehicle speed or higher. Clutch hold signal b is at high level,
Vehicle speed signal c is at high level. Therefore, the low level signal converted by the inverter 45 turns on the transistor 46, and the resistors 47 to 49 turn on.
The high-level reference signal _f1 resulting from the divided voltage of is sent to comparator 5.
1. Furthermore, since the low level signal from the inverter 45 is converted to a high level by the inverter 58, the transistor 59 is turned off, and the low level reference signal is generated by the voltage division of the resistors 61 and 62.
j ₁ will be applied to comparator 65. When a speed change operation is performed in this state, the speed change signal a changes from high level to low level, is converted to high level by inverter 40, and turns on transistor 41. Therefore, the capacitor 4 of the charging circuit 44
3 is discharged, and the output of the charging circuit 44 drops to zero level and is output to the comparator 51. Comparator 5
1, the signal e from the charging circuit 44 and the reference voltage generating circuit 50 is compared with _f1 , and when the signal e is lower than the signal _f1 , a high level signal g is output. When a high level signal is input to the AND gate 52, since the vehicle speed signal c is at a high level, the AND gate 52 outputs a high level signal as indicated by n. Next, since the triangular wave signal i output from the triangular wave oscillation circuit 64 and the reference signal j ₁ from the reference voltage generation circuit 63 are applied to the comparator 65, the comparator 65 receives the reference signal j more than the triangular wave signal i. It outputs a high level only when ₁ is high, and outputs a solid pulse wave indicated by k to the NAND gate 53. Since the high-level signal g from the comparator 51 is input to the NAND gate 53, it outputs a pulse wave m that is the inverse of the pulse wave k. Then, the NAND gate 54 outputs a signal p synthesized from the signals n and m to an AND gate 55, but unless the speed change signal a becomes a high level, the AND gate 55 outputs a low level, and therefore the transistor 56 is turned off. state, and no clutch current flows. When the speed change operation is completed and the speed change signal a changes from a low level to a high level, the AND gate 55 changes the signal p.
Among them, only the high level portion of the pulse wave is outputted, and a waveform shown by q is outputted, the transistor 56 is turned on and off, and a pulsed periodic current is caused to flow through the coil 7. As a result, a half-clutch current smaller than the rated current flows through the coil 7, and the electromagnetic powder clutch 1 transmits torque while causing the driven member 10 to slide. When the speed change signal a changes from a low level to a high level, the inverter 4
0 turns off transistor 41 and capacitor 4
3 is released from the short state, and the capacitor 43 is charged via the resistor 42. Therefore, the voltage of the signal e from the charging circuit 44 gradually increases in a parabolic manner, and when the voltage becomes higher than the signal _f1 from the adding circuit 51, the comparator 51 goes low as shown by r. Outputs a level signal. Therefore, the output n of the AND gate 53 also becomes a low level, the NAND gate 54 becomes a high level, and the AND gate 55 becomes a high level state together with the shift signal a, which is a high level signal, turning on the transistor 56 and turning on the coil 7. The electromagnetic powder type clutch 1 is directly connected by passing a rated current through the terminals. The change in the current flowing through the coil 7 has a waveform indicated by u. When the accelerator pedal 73 is depressed by 1/4 to 1/3 or more after shifting when the vehicle speed is higher than the set speed (rapidly accelerating). Clutch hold signal b is at low level,
Therefore, the transistor 46 is off, the transistor 59 is on, the reference signal from the reference voltage generation circuit 50 becomes low level _f2 , and the reference signal from the reference voltage generation circuit 63 becomes high level _j2 . . With this reference signal _f2 , when the output of the comparator 51 becomes a low level after the shift signal a becomes a high level, this is indicated by s, and the timing of the change is brought forward. Furthermore, since the potential of the reference signal j ₂ increases, the waveform of the pulse wave k output from the comparator 65 has a broken line shape, and the pulse width changes greatly.
For this reason, the pulse width of the pulse wave q for turning on and off the transistor 56 is also expanded, and since the on-time period becomes longer, the clutch current for half-clutching becomes larger. Furthermore, since the signal g changes from high level to low level quickly at time t, the time for the output of the AND gate 52 to switch from high level to low level is also shortened.
Therefore, the time for half-clutching is shortened. From this, the clutch current Ic changes as shown by v, the half-clutching time becomes shorter and the clutching current for half-clutching becomes larger than in other cases. The above signals a, b,
FIG. 6 shows the control of the clutch current by the combination of c. When driving steadily without shifting, the clutch current flows by the rated Im and the clutch is directly connected, as shown by A, but when the shift signal a changes from high level to low level, the clutch current changes as shown by B. becomes zero. When the speed change operation is completed and the speed change signal a is switched from low level to high level, the clutch current rises as shown by C, and the clutch is in a half-clutch state. Normally, the half-clutch current is I1, and after the current of I1 is passed for _t1 hour, the rated current Im is passed at time E to bring the clutch into reconnection state F, and the series of clutch controls is completed. In addition, in the case of acceleration, the half-clutch current is I2, and the time is t ₂
The clutch current can be varied in steps in the order of C→G→J. In this way, in this embodiment, the state of the half-clutch can be varied in two stages depending on the amount of depression of the clutch pedal, making it possible to perform detailed control that matches the operating situation. Next, FIG. 7 shows another embodiment of the acceleration detecting means, in which a throttle shaft 81 is pivotally supported in a suction pipe 80 of a carburetor, and a throttle valve is attached to the throttle shaft 81 in the suction pipe 80. 82 is fixed. A half-moon-shaped wire drum 83 is fixed to the throttle shaft 81 outside the suction pipe 80, and an accelerator wire 84 is wound around the outer periphery of the wire drum 83. Further, a slider 85 is fixed to the tip of the throttle shaft 81, and a resistor 87 wound around the outer circumference of a circular ring 86 is brought into contact with the slider 85. This ring 86
is made of an insulating material such as plastic,
It is located concentrically with the throttle shaft 81.
Terminals 88 and 89 are fixed to two places on the ring 86, and a resistor 87 is attached to these terminals 88 and 89.
Both ends of are connected. FIG. 8 shows the signal processing circuit from FIG. 7, in which an amplifier 90 is connected to the contact 85, and a differential circuit 91 is connected to the output of the amplifier 90. A determining circuit 92 is connected to this differentiating circuit 91, and the output of this determining circuit 92 is taken out as a high or low acceleration detection signal. Next, to explain this embodiment, the accelerator wire 84 is pulled in conjunction with the accelerator pedal, rotates the throttle shaft 81 and the throttle valve 82 via the wire drum 83, and supplies a large amount of air-fuel mixture to the engine. to accelerate. This rotation by the throttle shaft 81 causes the slider 85 to follow at the same time, changing the position where the slider 85 contacts the resistor 87, and varying the voltage input to the amplifier 90. The voltage input to the amplifier 90 is amplified by the amplifier 90 and input to the differentiating circuit 91 to differentiate the voltage fluctuation so that the throttle shaft 81 has a positive or negative potential depending on the acceleration direction or deceleration direction. Output. The judgment circuit 92 extracts only the signal in the acceleration direction from among the signals transmitted from the differentiating circuit, and outputs a high level signal when the signal changes in the acceleration direction. The output signal 93 of this judgment circuit 92 is
Input to c in the figure, clutch hold switch 7
Perform the same operation as in step 8. FIG. 9 shows yet another embodiment of the acceleration detection means, in which an intake pipe 97 is provided to communicate between the carburetor 95 and the engine 96,
A negative pressure switch 98 is installed on the side wall of the intake pipe 97, and an exhaust pipe 99 is connected to the exhaust port of the engine 96. Figure 10 shows this negative pressure switch 98.
The internal hollow cylinder 100 is airtightly separated into a pressure chamber 102 and a switch chamber 103 by a diaphragm 101.
2 and the switch chamber 103 are airtightly separated.
The pressure chamber 102 is communicated with the intake flow path of the suction pipe 97, and the switch chamber 103 is pressurized with atmospheric pressure. A coil spring 104 is inserted into the pressure chamber 102, and an actuating body 105 is interposed between the coil spring 104 and the diaphragm 101.
In addition, a diaphragm 10 is installed in the switch chamber 103.
1 is provided. The operation by this negative pressure switch 98 is
When the negative pressure 7 is shallow (when the accelerator pedal is depressed), the pressure difference between the pressure chamber 102 and the switch chamber 103 is small, and the coil spring 104 causes the actuating body 10 to
5 is turned on by pressing the micro switch 106, and when the negative pressure is deep (when the accelerator pedal is released), the pressure difference is large, so the diaphragm 101 is turned on.
As a result, the coil spring 104 is compressed, and the micro switch 106 is turned off. Therefore, the output of the microswitch 106 becomes a signal for detecting the deceleration state. The output signal of this microswitch 106 is input to c in FIG. 3, and performs the same operation as the clutch hold switch 78.

【Effect of the invention】

Since the present invention is configured as described above, a charging circuit that inputs a gear shift signal and outputs a zero level signal when the shift lever is operated, and a predetermined comparison based on the clutch hold signal that is output when the vehicle decelerates and accelerates. a first reference voltage generation circuit that outputs a reference voltage; a first comparator that compares and detects the output signal from the charging circuit and the output signal from the first reference voltage generation circuit; a second reference voltage generation circuit that outputs a comparison reference voltage; a triangular wave oscillation circuit that outputs a triangular wave signal; and a second reference voltage generation circuit that compares the output signal from the second reference voltage generation circuit with the output signal from the triangular wave oscillation circuit.
a comparator and a switching circuit for controlling the current to the coil of the electromagnetic clutch.
Based on the output signal from the comparator, the detection means detects the acceleration state of the vehicle and controls the current to the coil of the electromagnetic clutch.
Since the amount and time of energization to the clutch are controlled during deceleration and acceleration, it is possible to control the clutch current in accordance with the acceleration/deceleration state of the vehicle.
Clutch engagement characteristics can be optimized. Furthermore, during gear shifting operations, the clutch engagement time during deceleration can be made longer than the clutch engagement time during acceleration, making it possible to alleviate the shift shock that occurs when downshifting during deceleration. At the same time, during acceleration, the half-clutch current can be increased to reduce clutch slippage. Furthermore, the clutch engagement time can be set according to the operating state using a simple electric circuit, and no special additional equipment is required, so the control system can be made compact.

[Brief explanation of drawings]

Fig. 1 is a sectional view showing an electromagnetic powder clutch embodying the present invention, Fig. 2 is a sectional view taken along the Z-Z line in Fig. 1, and Fig. 3 is an electric circuit showing an embodiment of the present invention. , FIG. 4 is a perspective view showing the vicinity of the accelerator, FIG. 5 is a timing chart showing changes in signals at various parts in FIG. 3, FIG. 6 is a graph showing changes in clutch current, and FIG. 7 is a diagram showing other embodiments. Perspective view shown, No. 8
9 is a partial sectional view showing still another embodiment, and FIG. 10 is a sectional view of the negative pressure switch in FIG. 9. 1... Electromagnetic powder clutch, 5... Crankshaft,
6... Drive plate, 7... Coil, 8...
Drive member, 9...Transmission input shaft, 10...
Driven member, 11...gap.

Claims (1)

[Scope of Claims] 1. A crankshaft is integrally connected to a drive member containing a coil through a drive plate, and a driven member of a transmission input shaft is closely fitted to the drive member through a gap, A shift signal output based on the operation of the shift lever of the transmission and a clutch hold signal output based on the acceleration or deceleration state of the vehicle are input to the control circuit, and the clutch current from the control circuit is supplied to the coil. In a vehicle electromagnetic clutch that transmits power by integrally restraining a drive and a driven member using electromagnetic force, a detection means for detecting the acceleration or deceleration state of the vehicle is provided, and the control circuit includes: a charging circuit that inputs the shift signal and outputs a zero level signal when the shift lever is operated; and a first standard that outputs a predetermined comparison reference voltage based on a clutch hold signal that is output when the vehicle decelerates and accelerates. a voltage generation circuit, a first comparator for comparing and detecting an output signal from the charging circuit and an output signal from the first reference voltage generation circuit, and outputting a comparison reference voltage based on the clutch hold signal. a second reference voltage generation circuit; a triangular wave oscillation circuit that outputs a triangular wave signal; and a second comparator that compares the output signal from the second reference voltage generation circuit with the output signal from the triangular wave oscillation circuit. , a switching circuit for controlling the current to the coil of the electromagnetic clutch, and detecting the acceleration state of the vehicle by the detection means,
Based on the speed change signal and the clutch hold signal, the amount of current and the energization time to the coil of the electromagnetic clutch are controlled by the output signals from the first and second comparators. A control device for electromagnetic clutches for vehicles.