JPS59106756A - Direct coupling controller for torque converter of automatic transmission gear for vehicle - Google Patents

Abstract

PURPOSE:To prevent the rotational speed of an engine during running at a low speed from being reduced to a level at which smooth rotation can not be held, by a method wherein, through detection of the braking condition of a vehicle, the lock up release range of a torque converter is increased on the lower car speed side during braking action. CONSTITUTION:When stepping on a brake pedal 195 is detected, a high level brake signal is inputted from a brake detector 109 to a lock up control 108 to vary a lock up schedule map. Namely, by stepping on a foot brake, a lock up release line in relation to the opening of a throttle is varied from theta1 to theta2, and a lock up release range is enlarged on the low throttle opening side. Thus, even if an acceleration pedal continues to be stepped on during deceleration, a direct clutch holds a non-engaged condition, and this enables unpleasant car vibration to be prevented from being produced as a result of the rotational speed of an engine being reduced to a level at which smooth rotation can not be maintained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a direct-coupling control device for a torque converter in a vehicle automatic transmission, and in particular, controls the operation of a direct-coupling clutch that can mechanically lock up input and output members of a hydraulic torque converter depending on vehicle speed and engine. The present invention relates to a direct-coupled control device for a torque converter that performs control based on a lock-up schedule map corresponding to indicators representing respective outputs.

Vehicles equipped with a hydraulic torque converter can continuously change the gear ratio, allowing for extremely smooth operation, but the inherent slippage of the fluid coupling makes it difficult to operate the transmission manually The disadvantage is that operational fuel efficiency is inferior to vehicles equipped with this system. To compensate for this drawback, many attempts have been made to mechanically lock up the torque converter to minimize slip loss under operating conditions in which the torque converter's torque amplification function can hardly be expected. . This mechanical lock-up does not completely lock up the torque converter, but it is better to lock it up gently to make it slippery to some extent at low speeds, absorbing engine vibrations,
Moreover, it is excellent because it can restore the torque amplification function by sliding the torque converter by depressing the accelerator pedal, and the present invention is a direct-coupled control device for the torque converter that increases the engagement force during lock-up in proportion to the vehicle speed. It has already been proposed by the applicant.

According to this direct-coupled control device, lock-up can be performed at extremely low speeds, but this necessarily means that the lock-up mechanism is operating until it is on the verge of stopping.

However, since the accelerator pedal is in the idle position just before the engine stops, the auxiliary transmission generally has the highest gear or one gear lower than this, and therefore the engine speed The speed will drop to a level where smooth rotation cannot be sustained. In order to prevent this, it has been proposed in the past to release the engagement of the direct coupling clutch when the engine is running at idle. However, many vehicle drivers have the habit of operating the accelerator and brake pedals with both feet, and these drivers may lightly press the accelerator pedal while pressing the brake pedal. In other words, the above conventional proposals do not solve the problem.

The present invention detects the braking state of the vehicle and increases the lock-up release area of the torque converter to at least one of the low vehicle speed side and the low throttle opening side during braking, thereby smoothing the engine rotation speed at low vehicle speeds. An object of the present invention is to provide a direct-coupling control device for a torque converter in an automatic transmission for a vehicle, which prevents the rotation from decreasing to an unsustainable level.

Hereinafter, an embodiment in which the present invention is applied to a vehicle automatic transmission with three forward speeds and one reverse speed will be explained with reference to the drawings. First, in FIG. 12 and then hydrodynamically to the turbine impeller 14. When there is a relative speed between the impellers 12 and 14 and a torque amplification effect occurs, the stake 16 bears the reaction force. A gear 13 is provided on the pump impeller 12, and a hydraulic pump 50 shown in FIG. 2 is driven via this gear 13.

Furthermore, when the reaction force of the stator 16 exceeds a certain value, the stator shaft 17 rotates, and the arm 17a at its tip presses the regulator valve 54 shown in FIG. 2, thereby increasing the line pressure, that is, the discharge pressure of the hydraulic pump 50. be enhanced.

A roller-type direct coupling clutch C is provided between the pump impeller 12 and the turbine impeller 14 to mechanically connect them.
d is provided. To explain this in detail with reference to FIGS. 2 and 2A, an annular drive member 3 having a drive conical surface 2 on the inner circumference is fixed to the inner peripheral wall 12a of the pump impeller 12. A driven member 5 having a driven conical surface 4 facing parallel to the driving conical surface 2 on its outer periphery is spline-fitted to the inner circumferential wall 14a of the twisted turbine impeller 14 so as to be slidable in the axial direction. A piston 6 is integrally formed at one end of the driven member 5, and this piston 6 is connected to the turbine impeller 1.
The hydraulic cylinder 7 provided on the inner circumferential wall 14a of the
The internal pressure of the cylinder 7 and the internal pressure of the torque converter 10 are simultaneously received on both the left and right sides.

A cylindrical clutch roller 8 is interposed between the driving and driven conical surfaces 2 and 4, and as shown in FIG. It is held by an annular retainer 9 so as to be inclined by a certain angle α with respect to the generatrix g of the virtual conical surface Ic passing through.

Therefore, when a hydraulic pressure higher than the internal pressure of the torque converter 10 is introduced into the hydraulic cylinder T at a stage when the torque amplification function of the torque converter 10 is no longer necessary, the piston 6, that is, the driven member 5 is pushed toward the drive member 3. be done. As a result, the clutch roller 8 is brought into pressure contact with the conical surfaces 2 and 4 on both sides. When the driving member 3 is rotated in the X direction shown in FIG. 2A with respect to the driven member 5 by the output torque of the Toki engine E, the clutch roller 8 rotates. 0 is inclined as described above, its rotation gives a relative axial displacement to both members 3 and 5 that causes them to approach each other. As a result, the clutch roller 8 bites between the two conical surfaces 2 and 4 and mechanically connects the two members 3.5, that is, the pump impeller 12 and the turbine impeller 14.

Even when the direct coupling clutch Cd is operated in this way, the output torque of the engine E exceeds the coupling force and the output torque of both impellers 12.14
If the clutch roller 8 acts between the conical surfaces 2 and 2, the clutch roller 8
, 4, slipping occurs.

As a result, the above-mentioned torque is divided into two parts, and a part of the torque is transmitted mechanically through the direct coupling clutch Cd, and the remaining torque is transmitted hydrodynamically through both impellers 12 and 14. A variable rate dynamic power splitting system is formed in which the ratio of the latter torque to the latter torque varies depending on the degree of slippage of the clutch roller 8.

If a reverse load is applied to the torque converter 10 in the operating state of the direct coupling clutch Cd, the rotational speed of the driven member 5 will become higher than the rotational speed of the driving member 3, so that the driving member 3 will be relatively faster than the driven member 5. The clutch roller 8 rotates in the Y direction in FIG. 2A, and the clutch roller 8 rotates in the opposite direction to that described above, applying a relative axial displacement to the members 3 and 5 to separate them from each other. As a result, the clutch roller 8 is released from the state of being wedged between the conical surfaces 2 and 4, and enters an idling state. The transfer of the reverse load from the turbine impeller 14 to the pump impeller 12 therefore takes place only hydrodynamically.

When the hydraulic pressure of the hydraulic cylinder 7 is released, the piston 6 receives the internal pressure of the torque converter 10 and retreats to its original position, so that the direct coupling clutch Cd becomes inactive.

Referring to FIG. 1, the output shaft 20 of the torque converter 10 also serves as the input shaft of the auxiliary transmission 18, and this output shaft, that is, the input shaft 20 of the auxiliary transmission 18 has a In order, the third speed drive gear 22, the second speed clutch C2
, the first speed clutch C1 is installed. Furthermore, the input shaft 20
When both clutches CI and C2 are engaged, the input shaft 2
A second speed drive gear 24 and a first speed drive gear 26, which rotate together with the second speed drive gear 26, are loosely fitted. Further, the second speed drive gear 24 is integrally provided with a reverse drive gear 25 .

A countershaft 30 parallel to the input shaft 20 is provided with a final drive gear 32, a third speed clutch C3,
A spline S1 that selectively engages with the second driven gear 34 or the reverse driven gear 35 and the first driven gear 36 are installed.

A one-sided clutch C4 is interposed between the first speed driven gear 36 and the countershaft 30, and transmits torque only in the direction of the driving torque from the engine E. Further, a third speed driven gear 38 is loosely fitted onto the countershaft 30, and rotates integrally with the third speed clutch C3 and the countershaft 30 when the third speed clutch C3 is engaged.

In addition, the two reverse gears 25.35 are idle gears■
are interlocked with each other through.

The driving torque of the final drive gear 32 is transmitted to the final driven gear 40, and is further transmitted to the left and right front wheels WL via a differential gear 42 that is integral with the final driven gear 40.

It is transmitted to WR. Note that when reversing, the selector sleeve 44 on the countershaft 30 is moved to the shift fork 73.
(See FIG. 2'), the countershaft 30 and the reverse driven gear 35 are engaged together, and the second speed clutch C2 is engaged. Thereby, the reverse torque is transmitted to the left and right front wheels WL and WR.

In FIG. 2, the hydraulic pump 50 is driven by the pump impeller 12 as described above, pressurizes the oil pumped up from the tank 52, regulates the pressure with the regulator valve 54, and then pressurizes the oil with the manual valve 54.
Send to 6. The spring bearing of the regulator valve 54 is attached to the arm 17a (first
(see figure), and when the reaction force of the stator 16 exceeds a value (in other words, when the torque amplification factor of the torque converter 1o exceeds a reference level), the splash receiver moves the cylinder 54a to the first position. Move it to the left in Figure 2. Accordingly, the stator spring 55 is compressed, and the pressure regulating spring 570 increases the set load. As a result, the discharge pressure of the hydraulic pump 50, that is, the oil pressure of the oil passage 51 is increased.

A part of the pressure oil whose pressure is regulated by the regulator valve 54 is guided into the torque converter 10 through an oil passage 6o including a throttle 58, and pressurizes the inside of the torque converter 10 to prevent cavitation. The pressure inside torque converter 10 is determined by the size of throttle 58 and the strength of spring 63 of check valve 64 provided in outlet oil passage 62 of torque converter 10 . The oil exiting the check valve 64 is returned to the tank 52 via an oil cooler (not shown).

The surplus of the oil discharged from the hydraulic pump 50 is supplied to each lubricating part via the oil passage 66, but in order to ensure the minimum required oil head at that time, the oil passage 66 is provided with a pressure regulating valve 68. is provided.

The pressure oil sent to the manual valve 56 via the oil path 51 is transferred to the throttle valve 56.
When the plunger 56a is in the neutral (N) position as shown, it is not sent in either direction. However, when the plunger 56a moves from the neutral (N) position by one step to the left in FIG. 2 and reaches the forward (D) position, the oil passage 51 is connected to the oil passage TO which communicates with the first speed clutch C1. and is connected to the spring chamber 74 of the hydraulic servo motor 2 for moving the selector sleeve 44. At this time, the first speed gear ratio is established. At the same time, the hydraulic servomotor 72 remains in the leftward movement position shown and holds the selector sleeve 44 in the first shown position via the shift fork 73, so that the reverse gear train 25.1.35
is placed in the inoperative position.

Pressure oil introduced into the spring chamber 74 of the hydraulic servo motor 72 is guided to the modulator valve 78 via the oil passage 76, and after the upper limit pressure is regulated by the modulator valve 78, the oil is introduced into the oil passage 8.
The oil is guided to the right end chamber of the 1-2 shift valve 82 via the 0 and throttle 84, and to the right end chamber of the 2-3 shift valve 83 via the oil passage 80 and the throttle 85. The right end chambers of these shift valves 82.degree. 830 are connected to the tank 52 through oil passages 86.87, respectively, and poppet-type solenoid valves 8B and 897JZ are provided in the middle of each oil passage 86.87, respectively.

Plunger 82a of each shift valve 82.83.

83a is biased to the right by the spring force of springs 82b and 83b housed in the left end chamber, and operates in accordance with the hydraulic pressure in the right end chamber. That is, when hydraulic pressure acts in each right-end chamber, the plungers 82a, 83a move to the left against the spring force of the springs 82b, 83b, and when the hydraulic pressure in each right-end chamber is released, the plungers 82a, 83a move against the springs 82b, 83b. It is energized and moves to the right.

When the silane 82a of the 1-2 shift valve 82 is in the rightward movement position shown in the second figure, the oil passage 71 branched from the oil passage 70
is blocked by the plunger 82a, and only the first speed clutch C1 is engaged under pressure.

Further, the plunger 82a is in the left movement position, and 2-3
When the plunger 83a of the shift valve 83 is in the rightward movement position shown in the second figure, the oil passage 71 is connected to the oil passage 90 via the 1-2 shift valve 82 and the 2-3 shift valve 83, and is further in the "D" position. The manual valve 56 is connected to the oil passage 91 through an annular groove 59 therein. As a result, the second gear clutch C2
are engaged under pressure. At this time, the first speed clutch C1 is also still pressurized, but the second speed gear ratio is established by the action of the one-way clutch C4 (see FIG. 1).

When the 1-2 shift valve 82 remains in the leftward movement position and the 2-3 shift valve 83 also moves to the left, the oil passage 1 is connected to the 3rd speed clutch C3 via these two shift valves 82 and 83. At the same time, the oil passage 90 is connected to the tank 52. Therefore, the second gear clutch C2 is released from the engaged state, and the third gear clutch C2 is released from the engaged state.
The top gear ratio is established.

The right or left movement of each plunger 82a, 83a in the 1-2 shift valve 82 and 2-3 shift valve 83 is caused by the solenoid 88a, 89 in the corresponding solenoid valve 88.89.
This corresponds to excitation or deactivation of a, respectively. That is, in each solenoid valve 88, 89, solenoids 88a, 89
a is energized, a poppet-type valve body 88b,
89b is drawn into the solenoids 88a and 89a to open the valves, and when the solenoids 88a and 89a are demagnetized, the spring 8
The valve is closed by the spring force of 8c and 89c.

Therefore, as the solenoids 88a and 89a are energized, the pressure inside the right end of each shift valve 82, 83 decreases, causing the grangers 82a and 83a to move to the right, and conversely, when the solenoids 88a and 88b are demagnetized, Each shift valve 8
2.83 right end chamber 1] Pressure increases and each plunger 8
2a and 83a move to the left.

The above is an explanation of the engaged state of each clutch 01 to C3 when the manual valve 56 is in the D position. However, the plunger 56a of the manual valve 56 further moves to the left and reaches the position tt2.
When placed in the position, the oil passage 70 is cut off from the oil passage 51,
In response, the first speed clutch C1 becomes disengaged. Further, the oil passage 51 is connected to the second speed clutch C2 via the oil passages 75, 77, the annular groove 59, and the oil passage 91, and the second speed clutch C2 is engaged with pressure accordingly. At the same time, the third speed clutch C3 operates the 2-3 shift valve 83.1.
-2 solenoid 88a, because it is connected to tank 52 via either one of shift valve 82 or manual valve 56;
The second gear ratio is established regardless of the magnetization and demagnetization of 89a.

When the plunger 56a of the manual valve 56 moves to the right from the position shown in the second figure and is placed in the retreat (R) position, the high pressure oil passage 51 is connected to the left end chamber T9 of the hydraulic servo motor 72.
6. In response, the piston 72a of the hydraulic servo motor 72 first moves to the right, moves the selector sleeve 44 (see FIG. 1) to the right, and moves the FM warehouse row 25 for retreat.
1.35 becomes the operating state. Next, the oil passage 51 is connected to the oil passage 77 through an oil passage 72b in the axis of the piston 72a, and is further connected to the second speed clutch C2 through another annular groove 61 of the manual valve 56. This establishes reverse speed.

Table 1 summarizes the correspondence between each gear stage and the energized or deenergized state of the solenoids 88a and 89a of the solenoid valves 88 and 89 in the above description.

Table 1 Here, when the torque converter 10 stalls, it is necessary that the discharge oil pressure of the hydraulic pump 50, that is, the line pressure, be at the highest level, so the amount of pressure oil returned from the control system to the tank 52 should be minimized. However, this is desirable in order to reduce the capacity of the hydraulic pump 50 and save energy. Therefore, when the solenoid 89a in the first speed is "arbitrary" in Table 1, the "demagnetized" state should be selected so that the amount of oil returned from the solenoid valve 89 to the tank 52 should theoretically be zero. However, if the manual valve 56 is in the ND position and there is no delay in operation when shifting from 1st gear to 2nd gear, it is necessary to keep the solenoid 89a in the "energized" state while in 1st gear. It is preferable to keep it on standby. Therefore, there are mutually contradictory requirements, but according to this embodiment, the solenoid 89g is demagnetized and the first
Solenoid 89a is activated just before shifting up from speed to second speed.
The above-mentioned two contradictory requirements are satisfied by exciting the magnet.

A part of the discharge pressure of the hydraulic pump 50 is guided to a governor 93 via an oil passage 92 branched from the oil passage 51.

The casing 94 of the governor 93 is rotationally driven about an axis 96 by a governor drive gear 95 that meshes with the final driven gear 40 . Due to the centrifugal force acting on the weight 97 due to this rotational movement and the spring force of the spring 98, a force directed upward in FIG. 2 is applied to the valve body 99. Further, a downward force is applied to the valve body 99 by an output pressure acting on a shoulder portion 99a that creates a difference in cross-sectional area at the lower portion. As a result, the output oil path 116
, a governor pressure PG is generated which is given by a quadratic curve as shown in FIG. 4(b). The governor pressure Pc when the vehicle speed is 0 at 2 in FIG. 4(b) is determined by the set load of the spring 98.

The output oil passage 116 is connected to the hydraulic cylinder 7 of the direct coupling clutch Cd via the lock amplifier control valve 11\oil passage 117, which uses the solenoid valve 114 as a pilot valve.

The governor pressure Pc of the output oil passage 116 acts on the right end chamber of the lock-up control valve 115 via the throttle 118. This right end chamber is connected to the tank 52 via a solenoid valve 114. The plunger 115a of the lock-up control valve 115 is biased to the right by the spring force of a spring 115b housed in the left end chamber, and operates in accordance with the hydraulic pressure in the right end chamber. That is, the solenoid 114a of the electromagnetic valve 114 is deenergized, and the valve body 1
14b is closed by the spring force of the spring 114c, governor pressure PG from the governor 93 acts on the right end chamber of the lock-up control valve 115, and when that pressure overcomes the spring force of the spring 115b, the plunger 115a is closed as shown in the second figure. Move to the left like this. As a result, the oil passage 117 communicating with the hydraulic cylinder 7 of the direct coupling clutch Cd is opened to the atmosphere via the annular groove 119 provided on the outer peripheral surface of the plunger 115a. Therefore, atmospheric pressure acts on the left end face of the piston 6 in the direct coupling clutch Cd, and internal pressure of the Nitorque converter 10 acts on the right end face, and as a result, the piston 6
moves to the left and does not have a lockup effect.

In response, the solenoid 114a is energized and the solenoid valve 1
14 opens, the right end chamber of the lock-up control valve 115 is communicated with the tank 52, and is maintained at a low pressure by the action of the throttle 118, so that the plunger 115a is moved by the spring 115.
It moves to the right due to the spring force of b. As a result, the output oil path 116
is communicated with the oil passage 117 via the annular groove 119, and the governor pressure P is applied to the hydraulic cylinder 7 of the direct coupling clutch Cd.
a acts to perform a lock-up effect.

The lock-up engagement force of the direct coupling clutch Cd at this time is
The internal pressure PO of the torque converter 10 acting on the right side of the piston 6 is almost constant as shown in FIG. The governor pressure PG, which acts on the left side of the vehicle and performs the engagement action, is proportional to the square of the vehicle speed, as described above. Therefore, the overall lock-up engagement force is also approximately proportional to the square of the vehicle speed, and since the required torque of the engine E increases in proportion to the vehicle speed during cruising, an extremely desirable engagement force can be obtained.

Note that when the accelerator pedal is temporarily depressed when overtaking, etc., the torque of the engine E exceeds the lock-up engagement force and causes the torque converter 10 to slip, so part of the power flows through the torque converter 10 and the power is reduced. A split system is formed. This slippage also causes the engine speed to rise slightly.

Therefore, it is possible to greatly alleviate the feeling of insufficient power when driving at low speeds, which is common when conventional systems that lock up completely lock up from low speeds. Furthermore, since the lock-up engagement force is small at low speeds, the fluctuating peak torque of engine vibrations at low speeds is not transmitted, allowing smooth operation.

In FIG. 3 showing a control circuit for controlling solenoids 88a, 89a, and 114a, a vehicle speed detector consisting of a vehicle speed sensor 100 and a vehicle speed detection circuit 1 is a first
A 6-bit digital signal vo to V5 corresponding to the vehicle speed as an index is applied to the shift position determining circuit 1042 and the lockup control circuit 108, respectively. An engine output detector composed of a twisted throttle sensor 102 and a throttle detection circuit 103 sends a 3-bit digital signal Th0 to TH2 corresponding to a throttle opening degree as a second index representative of engine output to a shift position determining circuit. 104
and is applied to the lockup control circuit 108. The shift position determination circuit 104 generates a shift signal ShO+Sht according to the input vehicle speed signal and throttle signal.

Sb2 is applied to the solenoid control circuit 110, and the solenoid control circuit 110 controls the solenoid drive circuit 111,
A drive signal is given to 112. Moreover, the shift position determination circuit 1
04 and the solenoid control circuit 110 are configured to output a signal for exciting the solenoid 89a just before shifting up from the first gear to the second gear. The lock-up control circuit also includes a brake detector 109.
A braking signal as a third indicator representative of the braking state is given from 1 to 3, and the lock-up control circuit 108 receives a fourth indicator, which will be described later, in response to the vehicle speed signal, throttle signal, and braking signal.
A drive signal is applied to the solenoid drive circuit 113 of the solenoid 114a based on the lockup schedule map described in detail in connection with FIG. 5A and FIG.

To explain the configuration of each circuit in detail, first, the vehicle speed sensor 10
0 is composed of a reed switch 105 fixed in a proper position on the vehicle body, and a member that rotates in conjunction with the wheels, such as a magnet 107 fixed to a speedometer cable 106, which converts the rotation of the speedometer cable 106 into a pulse signal. and provides it to the vehicle speed detection circuit 101.

In the vehicle speed detection circuit 101, the signal from the vehicle speed sensor 100 is detected by the resistance! 120. ．． 121, a flip-flop 124 via a capacitor 122 and an inverter 123
is input to the data input terminal. flip flop 1
The 240 set output Q is applied to the data input terminal of the flip-flop 125, and is also applied to the NOR gate 126.
is applied to one input terminal of .

The other input terminal of NOR gate 126 is provided with the reset output page of flip-flop 125.

The output of the NOR gate 126 is applied to the clock input terminal C of the counter 134, and is also applied to the NAND gate (12).
It is applied to one input terminal of B.

The other input terminal of NAND gate 128 is connected to timer 1.
27 output Q12 is given and 'NANDNOR
The gate 126 is applied to the data input terminal of the flip-flop 129. The reset output q of this flip-flop 129 is applied to the 1) set input terminal R of the timer 127. The output Q12 of the timer 127 is also applied to one input terminal of a NOR gate 131, one input terminal of a NAND gate 132, and a data input terminal of a flip-flop 130. The reset output of the flip-flop 130 is applied to the other input terminal of the NOR gate 131 and the other input terminal of the NAND gate 132, respectively, and the output of the NOR gate 131 is applied to the counter 134.
and one input terminal of NOR gate 137, respectively.

Further, the output of the NAND gate 132 is applied to a NOR gate 138 via an inverter 133.

The outputs Q1 to Q4 of the counter 134 are individually given to input terminals A-D of the converter 1390, and the NA
are respectively applied to ND gates 135. Also, the output Q5 of the counter 134. Q6 is converter 1400 input terminal A,
H and the NAND gate 13
5 each. The output of NAND gate 135 is provided to NOR gate 138 via inverter 136.

The output of NOR gate 138 is given to the other input terminal of NOR gate 137, and the output of NOR gate 137 is
They are applied to the remaining input terminals of OR gate 138 and to clock input terminals CK of converters 139 and 140, respectively.

An oscillation circuit 148 is attached outside the vehicle speed detection circuit 1. In this oscillation circuit 148, a series circuit consisting of a resistor 145 and a variable resistor 146, and a series circuit consisting of three inverters 141, 142, 143 are connected in parallel, and two inverters 141, 142 are connected in parallel.
A capacitor 147 is connected in parallel with . Oscillation circuit 14
The clock pulses from 8 are sent to flip-flops 124,
125 and 129, respectively, and via an inverter 144 to each clock input terminal C of the timer 1272 and flip-flop 13v).

The vehicle speed detection circuit 101 configured as described above is a so-called counter circuit, which counts input pulses from the vehicle speed sensor 100 for a certain period of time set by the timer 127, and calculates the counted number by vo- v5 no 6
Output as a bit digital signal. That is, from the output terminals Q'A, QB, QC, and QD of the converter 139, v
4-bit digital signals o to ■3 are output, and output terminals QA and QB of the converter 140 output signals ■4. ■A 502-bit digital signal is output.

The throttle sensor 102 is a potentiometer provided in connection with a throttle valve shaft (not shown) of the engine E, and sends a signal voltage corresponding to the opening degree of the throttle valve to the amplifier 1 of the throttle valve detection circuit 103.
In the throttle detection circuit 103, the output of the amplifier 155 is fed to the comparators 164, 165, 16.
6.167.168°169.170 are applied to each non-inverting input terminal. Also, the comparator 164
Each inverting input terminal of ~170 has a voltage dividing resistor 156, 15
7,158,159,160゜161.162.163
A reference voltage divided by is given respectively. The output of the output comparator 164 is connected to NAND via the inverter 171.
gate 183 and NAND gate 17
is applied to one input terminal of 2. Comparator 165
The output of is applied to the other input terminal of NAND gate 172 and, via inverter 173, to one input terminal of NAND gate 174. The output of the comparator 166 is applied to the other input terminal of the NAND gate 174 and is passed through the inverter 175 to the NAND gate 174.
It is applied to one input terminal of the ND gate 176. The output of comparator 167 is applied to the other input terminal of NAND gate 176 and, via inverter 177, to one input terminal of NAND gate 178. The output of comparator 168 is applied to the other input terminal of NAND gate 178.
is applied to one input terminal of the NAND gate 180 via the NAND gate 180. The output of comparator 169 is NAND gate 1
80 and one input terminal of a NAND gate 182 via an inverter 181. The output of comparator 170 is provided to the other input terminal of NAND gate 182. NAND gate 172. The output of NAND gate 183.184 is applied to NAND gate 183.184, the output of NAND gate 174 is applied to NAND gate 183.185, the output of NAND gate 176 is applied to NAND gate 183, the output of NAND gate 178 is applied to NAND gate 184, 185 and the output of NAND gate 180 is applied to NAND gate 1
84 and the output of NAND gate 182 is NAN
The signal is applied to D gate 185. Each NAND gate 183
The output of ゜184・185 is a flip-flop 186,
A clock pulse is applied to the clock input terminals C of each of the seven lip-flops 186 to 188 from the aforementioned oscillation circuit 148.

Such a throttle detection circuit 103 generates a three-focus digital signal Tho +T1111 corresponding to the throttle opening based on the detection signal of the throttle sensor 102.
'Output rh2. That is, flip-flop 188
The digital signal Tho is output as the set output Q from the flip-flop 187, the digital signal Th1 is output as the set output Q from the flip-flop 187, and the digital signal Th1 is output from the flip-flop 187 as the set output Q.
6 outputs a digital signal Th2 as a set output Q. Moreover, by selecting the resistance values of the voltage dividing resistors 156 to 163, it is possible to make the relationship between the throttle opening and the output nonlinear.

The shift position determining circuit 104 includes a memory element 189, and input terminals AO to A5 of this memory element 1890 receive vehicle speed signals ■0 to ■5, respectively, and input terminals A6 to A88 receive a throttle signal Tho-'rh2. Each is input. Note that the input terminal AIO is grounded.

The memory element 189 stores in advance a shift map according to the vehicle speed 2 and the throttle opening, and input terminals AO to A8
Based on the vehicle speed signal and throttle signal input to the output terminal DO
, DI, and D2, respectively.

The shift position determining circuit 104 includes an inverter 190.
and a NOR gate 191, but since they are irrelevant to the present invention, their explanation will be omitted.

In such a shift position determination circuit 104, generally two
Although the speed change characteristics can be obtained with only one speed change signal ShO*Shl, in this embodiment, as described above, the solenoid 89a is demagnetized in the first speed to reduce the amount of pressure oil returned to the tank 52, and Just before shifting up from the first speed to the second speed, a shift signal Sh2 is output to excite the solenoid 89a. Here, the relationship between the speed ratio and the speed change signals Sho and Sh1 is shown in Table 2.

Table 2 In Table 2, ηL〃 indicates a low level, and whisper H
〃 indicates a high level.

In FIG. 4(,), the 1-2 shift line LL indicated by a dashed line indicates the switching position from 1st gear to 2nd gear, and the 2-3 shift line LH indicated by a dashed dotted line indicates the shift position from 2nd gear to 3rd gear. Indicates the switching position to speed. '1. The shift signal Sh2 is at a low level to the left of the vehicle speed U1, and is at a high level to the right of the vehicle speed U1.

Referring again to FIG. 3, the solenoid control circuit 110 includes a series circuit consisting of inverters 204 and 205 corresponding to the solenoid 88a, and a NAN circuit consisting of the inverters 204 and 205 corresponding to the solenoid 89a.
D game) 206s and a series circuit consisting of an inverter 2o7. The inverter 204 is given a shift signal Sho from the shift position determination circuit 104, and the NAN
A shift signal Shl + Shz from the shift position determining circuit 104 is applied to the D game +2o6.

The solenoid drive circuit 111 includes a transistor 209 as a switching element connected to the solenoid 88a, and the output of the inverter 205 in the solenoid control circuit 110 is applied to the base of this transistor 2090 via a resistor 208. Therefore, the speed change signal Sh
When o is at level 7, the transistor 209 becomes conductive, the solenoid 88a is energized, and the solenoid valve 88 opens.

When the shifted shift signal Sho is at a low level, the transistor 209 is cut off, the solenoid 88a is demagnetized, and the electromagnetic valve 88 is closed.

The solenoid drive circuit 112 includes a transistor 211 as a switching element connected to the solenoid 89a, and the output of the inverter 207 in the solenoid control circuit 110 is applied to the base of the transistor 2110 via a resistor 210. Therefore, when the signal applied to the base of transistor 2110 is at high level,
That is, only when both of the speed change signals Sh1 + Sb2 are at a high level, the transistor 211 becomes conductive and the solenoid 89a is excited. To explain with reference to FIG. 4(,), the shift signal Sh is at a high level to the left of the vehicle speed U1, but the shift signal sh2 is at a low level, so the solenoid 89a is demagnetized, and the vehicle speed U1 and 2- 3
Both shift signals Sh1. Sh2
is at a high level, so the solenoid 89a is energized,
Also, on the right side of the 2-3 shift line LH, the shift signal S
Since the shift signal Sh1 is at a low level while h2 is at a high level, the solenoid 89a is demagnetized.

The lock-up control circuit 108 includes a memory element 192, and vehicle speed signals 10-v5 are input to input terminals AO-A5 of the memory element 1920, respectively. Also, input terminal A
Throttle signals Tho to Th2 are input to 6 to A8, respectively. This memory element 192 stores in advance a lock-up schedule map corresponding to vehicle speed and throttle opening as shown by solid lines and broken lines in FIG. In addition, the input terminal A10 of the memory element 192
is given a braking signal from the braking detector 109,
During braking, the memory element 192 changes the lock-up schedule map shown in FIG. 4(a) as shown in FIG. 5. A lock amplifier signal according to such a lock-up schedule map is applied from output terminal Do to solenoid drive circuit 113 via inverters 193 and 194, and is also input to input terminal A9.

Brake detector 109 is provided in association with brake pedal 195, for example. That is, a brake lamp 197 is connected in series to a switch 196 that is linked to the brake pedal 195, and when the brake pedal 195 is depressed and the switch 196 becomes conductive, that is, when the brake lamp 197 lights up, the switch 196 and the brake lamp 197 are turned on.
A high-level braking signal is applied to the input terminal AIO of the memory element 1920 from the connection point of the memory element 1920 through the resistors 198 and 199, the capacitor 200, and the inverter 212.

The solenoid drive circuit 113 includes a transistor 213 as a switching element connected in series to the solenoid 114a, and the output from the output terminal DO of the memory element 192 is connected to the base of the transistor 2130 to the inverter 1.
93.194 and resistor 214 are provided at the valve port. Therefore, when the output of the output terminal Do is at a high level, the transistor 213 becomes conductive, the solenoid 114a is energized, and the solenoid valve 114 opens accordingly. Conversely, when the output is at a low level, transistor 213 is cut off, and therefore solenoid 1
14a is demagnetized and the solenoid valve 114 is closed.

Next, the operation of this embodiment will be explained as shown in Fig. 4(a).
), first assume that the vehicle starts at throttle opening θ0. In this case, the direct coupling clutch Cd does not operate until the vehicle speed reaches Ul, and the gear ratio is at the first speed, so that the vehicle starts in exactly the same way as a conventional vehicle with an automatic transmission. Next, when the vehicle speed exceeds Ul, the lock amplifier control circuit 108
A high-level lock-up signal is given to the solenoid drive circuit 113 from the solenoid drive circuit 113, and the solenoid 114a is energized.
Direct coupling clutch Cd begins to operate. However, the engagement force is due to the hydraulic pressure (Pl-PO) obtained by subtracting the internal pressure PO of the torque converter 10 from the governor pressure P1 at vehicle speed U1, and is so small that the torque converter 10 loses its original function. Therefore, sufficiently strong starting acceleration is maintained.

Further, when the vehicle speed reaches Ul, the solenoid 89a is switched from demagnetized to energized to prepare for establishing the next second gear ratio. By demagnetizing the solenoid 89a near the stall of the torque converter 10, the amount of pressure oil returned to the tank 52 can be reduced at the stall when the highest line pressure, that is, the discharge pressure of the hydraulic pump 50 is required. As a result, the capacity of the hydraulic pump 50 can be made relatively small to save energy.

When the vehicle speed increases further and reaches Ul-2, the solenoid 88a is demagnetized to establish the second speed gear ratio, and when the vehicle speed increases further and reaches Ul-3, the solenoid 88a is demagnetized.
a is demagnetized and the third speed gear ratio is established.

Next, assume that the vehicle is decelerated from the vehicle speed U3 in the third gear. At this time, if the driver completely takes his foot off the accelerator pedal and decelerates, the throttle opening will go from position A to position B and reach the lock-up release line of throttle opening θ1, so the direct coupling clutch Cd will be protected. The connection will be cleared and no problem will occur. but,
Many drivers have the habit of operating the accelerator pedal and brake pedal with both feet. In urban areas where acceleration and deceleration are frequently repeated, these people keep one foot lightly on the accelerator pedal in preparation for the next acceleration operation and press the brake pedal 195 with the other foot to achieve the desired deceleration. try

In this way, when the vehicle is decelerated by the engine brake or the foot brake along B-+C in FIG. 4(a), if the lock-up control of the present invention is not performed, the lock-up is released until the vehicle speed drops to Ul. As a result, the rotational speed of the engine E decreases to a level where smooth rotation cannot be maintained, resulting in unpleasant vehicle body vibration.

Therefore, according to the present invention, when it is detected that the brake pedal 195 is depressed, a high-level braking signal is input from the braking detector 109 to the lock-up control circuit 108, and in response, the lock-up control circuit 108 The schedule map is changed as shown in FIG. That is, by applying the footbrake, the lockup release line relative to the throttle opening changes from θ1 to θ2 as shown in FIG. 5, and the lockup release area expands at the lower throttle opening. In this way, even if one foot continues to depress the accelerator pedal during deceleration to B-+C, the direct coupling clutch Cd is maintained in the disengaged state.

Therefore, it is possible to prevent the rotational speed of engine 5 E from decreasing to a level where smooth rotation cannot be maintained, thereby preventing unpleasant vehicle body vibrations from occurring.

In another embodiment of the present invention, the lock-up schedule map may be changed as shown in FIG. 6 during braking. That is, the lockup release area may be expanded at lower vehicle speeds by changing the lockup release line. Even if this is done, the lock amplifier is released early before the vehicle speed drops completely, so the rotational speed of the engine E will not drop to a level where smooth rotation cannot be maintained, as in the above embodiment. do not have.

As yet another embodiment of the present invention, the lock-up schedule map has a characteristic that combines FIGS. 5 and 6, that is, the lock amplifier release line is changed from throttle opening θ1 to 02, and at the same time the vehicle speed is changed from U1 to UB. In this way, the lock-up release area may be expanded at lower throttle openings and lower vehicle speeds.

In addition, in the above-mentioned embodiment, the speed change map is shown in FIG.
), step-like digital control is used as shown by the dashed-dotted line in FIGS. (Shift control using pure hydraulic pressure, which has been implemented, may also be used.) Furthermore, in FIGS. 4(a) and 6, the vehicle speed at which the lock-up should be released at the idle position of the throttle is set to be below U4, but it will be understood that this is also irrelevant to the present invention. Further, in FIG. 4(b), the internal pressure Po of the torque converter 10 is depicted as if it were constant, but this is only for convenience of explanation and is not actually constant. For example, under operating conditions of the torque converter 10 near stall, where the throttle opening is large and the vehicle speed is low, the line pressure is increased, so the amount of pressurized oil flowing into the torque converter 1o via the throttle 58 is increased. Sometimes, the internal pressure Po of the torque converter 10 also inevitably becomes high. In such a case, as shown in FIG. 4(a), even if the solenoid 114a is energized at the vehicle speed U1, the direct coupling clutch Cd cannot be expected to engage.
Although the pickup vehicle speed is delayed to U2, this is also not directly related to the present invention.

In the above embodiment, the throttle opening degree is used as an index representing the output of the engine E, but this can also be represented by the intake manifold negative pressure. Further, although the control signal is extracted in response to a change in the switching mode of the switch 196 connected to the brake lamp 197, a brake oil pressure signal, deceleration, etc. may also be used.

Further, the present invention is not limited to an automatic transmission with three forward speeds, but can be broadly implemented in an automatic transmission with four or more forward speeds.

As described above, according to the present invention, when braking the vehicle, the lock amplifier release area of the lock-up schedule map is set to the lower side of at least one of the first index representing the vehicle speed and the second index representing the engine output. This makes it possible to ensure that even if you decelerate the vehicle by depressing the accelerator pedal and the brake pedal, the engine rotational speed will drop to a level where smooth rotation cannot be maintained and the vehicle body will vibrate. can be prevented.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is a schematic diagram showing an embodiment when the present invention is applied to an automatic transmission with three forward speeds and one reverse speed, and FIG. Fig. 2A is an exploded view of the main parts of the direct coupling clutch shown in Fig. 2, and Fig. 3 shows the solenoids 88a, 89a, and
114a, FIG. 4 is a diagram for explaining the lock-up schedule map, and FIG. 5 is a T-diagram showing the changed lock-up schedule map.
FIG. 6 is a diagram without showing a modified lockup schedule map in another embodiment of the present invention. DESCRIPTION OF SYMBOLS 10... Hydraulic torque converter, 12... Pump impeller, 14... Turbine impeller, 1oO... Vehicle speed sensor which is one element of vehicle speed detector, 101... One element of vehicle speed detector A vehicle speed detection circuit, 102, which is a throttle sensor, which is an element of an engine output detector, 103
. . . Throttle detection circuit, which is an element of the engine output detector, 108 . . . Lock-up control circuit, 109.
...Brake detector, 195...Brake pedal be...
・Engine, CD...direct clutch. Procedural amendment (release) 1. Display of the case 1982 Patent Application No. 217638 3, Relationship with the amended case Patent applicant name (532) Honda Motor Co., Ltd. 4, Agent 105 Telephone Tokyo 434-4151 418-

Claims (1)

[Claims] a hydraulic torque converter having an input member including a pump impeller and an output member including a turbine impeller; a direct coupling clutch capable of mechanically directly coupling and locking up the input and output members of the converter; a vehicle speed detector that detects and outputs an index; an engine output detector that detects and outputs a second index representative of engine output; and actuation of the direct coupling clutch in response to the first and second indexes. It has a lock-up schedule map that determines the state, and outputs a signal for controlling the operation of the direct coupling clutch based on the lock-up schedule map in response to the first and second indicators inputted from the vehicle speed and engine output detector. A direct-coupled control device for a torque converter in a vehicle automatic transmission including a lock-up control circuit that includes a brake detector that detects and outputs a third index representative of the braking state of the vehicle, the lock amplifier control circuit The lock-up release area of the lock amplifier schedule map is expanded to the lower side of at least one of the first and second indicators when the third indicator indicating the time of braking is input from the braking detector. A direct-coupled control device for a torque converter in a vehicle automatic transmission, characterized in that it is configured as follows.