JPS60101342A - Speed change control method for automatic speed change gear - Google Patents

Abstract

PURPOSE:To always maintain an automatic speed change gear in the optimum operating condition by keeping the speed from changing to the top speed step when a throttle valve opening is comparatively large, that is, more than a designated value in an automatic speed change gear in which a part of function in a high speed range of a hydraulic control device is compensated by an electric control device. CONSTITUTION:A speed change control device of an automatic speed change gear including a plurality of frictional engagement devices for obtaining plural speed change steps has a valve element for controlling for permitting a speed change to the top speed step or not, and the supply of oil pressure to the valve element is controlled by a solenoid valve 92 which is controlled to turn on electricity by an electric arithmetic operation device 101. Output signals of a car velocity sensor 102 and a throttle sensor 103 for generating an electric signal according to a throttle valve opening are input to the electric arithmetic operation device 101, and the electric arithmetic operation device 101 is adapted to apply an electric current to the solenoid valve 92 on detecting that the throttle valve opening is more than a designated value, for example, 85%. In this arrangement, a speed change to the top speed step can be checked through the valve element.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to controlling the speed change of an automatic transmission for a vehicle using a speed change control device, and in particular to controlling the operating characteristics of a hydraulic control device that has conventionally been commonly used as this type of control device. This relates to electrically compensating for limitations.

In an automatic transmission for a vehicle that includes a hydraulic torque converter and a gear transmission mechanism equipped with a plurality of frictional engagement devices for obtaining several gears, the ftl friction changes depending on the driving state of the vehicle. The operation of the engagement device is changed over in various ways, and the gear transmission mechanism is automatically controlled to the most suitable speed change state for the driving condition of the vehicle at that time. Switching control of the friction engagement device is normally performed by a hydraulic control device, and this hydraulic control device has a control system that controls the throttle oil pressure, which changes depending on the amount of time the accelerator pedal is pressed, that is, the intake throttle opening, and the vehicle speed. A gear shift valve is built in that is switched to C depending on the equilibrium relationship of the changing governor oil pressure, and selects the gear position of the gear transmission mechanism based on the comparative relationship between the throttle oil pressure and the governor oil pressure, that is, the amount of accelerator pedal depression and the vehicle speed. It is supposed to be done. However, in the switching control of the transmission valve by such a hydraulic control device, a certain amount of oil leakage inevitably occurs in the throttle hydraulic control valve and the governor hydraulic control valve, which generate throttle hydraulic pressure and governor hydraulic pressure. Due to the structure of the hydraulic control device, there are naturally certain restrictions on the value of the line hydraulic pressure, which is the result of the throttle hydraulic pressure and the governor hydraulic pressure. The governor hydraulic control valve that generates the governor hydraulic pressure also has a limit to the vehicle speed that it can detect due to structural constraints, and these various constraints can increase the operating error of the hydraulic control device, especially in high vehicle speed ranges, or prevent it from operating properly. There is a problem that control operation cannot be obtained.

The present invention addresses the above-mentioned problems by incorporating an electric control device into the hydraulic control device of a vehicle automatic transmission, and supplementing part of the function of the hydraulic control device, especially in high-speed vehicle ranges, with an electric power all device. The purpose of this invention is to provide a multi-layered speed change control method capable of setting an automatic transmission to an optimal operating state in a wide range of vehicle operation ranging from low-speed to high-speed operating states.

According to the invention, such an object is to provide an automatic transmission including a hydraulic torque converter and a gear transmission mechanism with a plurality of frictional engagement devices for obtaining several gears, a hydraulic power source, A line hydraulic control valve that generates a line hydraulic pressure regulated from the hydraulic pressure source, a throttle hydraulic control valve that generates a throttle hydraulic pressure that corresponds to the intake throttle opening, and a governor hydraulic control valve that generates a governor hydraulic pressure that corresponds to the vehicle speed. a manual switching valve that manually switches the speed range; and a plurality of shift valves that switch the hydraulic pressure supplied to the forward friction engagement device according to the balanced relationship between the throttle hydraulic pressure and the governor hydraulic pressure.
A vehicle speed sensor that generates an electric signal according to the vehicle speed, a throttle sensor that generates an electric signal according to the intake throttle opening, and one end that is displaced depending on whether or not oil pressure is selectively supplied to determine the maximum speed. a valve element that controls whether or not to allow gear shifting; a solenoid valve that controls the supply of hydraulic pressure to the one end of the valve element; and an electric signal generated by the vehicle speed sensor and the throttle sensor. In the method of controlling the speed change using a speed change control device having an electric sieve actuating device that controls energization to the solenoid valve, the speed is changed to the highest speed gear when the throttle opening is equal to or higher than a relatively large predetermined value. This is achieved by a method characterized by preventing.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the drawings shown in FIG.

FIG. 1 is a schematic diagram showing an example of a hydraulic automatic transmission with an overdrive device. A more specific structure of such an automatic transmission is illustrated and explained in detail in Japanese Patent Application No. 159179/1979 filed by the same applicant as the present applicant, and if necessary, please refer to these applications. Referring to the specification and drawings, 1゜this automatic transmission includes a torque converter 1,
It includes an overdrive mechanism 2 and a gear transmission mechanism 3 with three forward speeds and one reverse speed, and is controlled by a speed change control device as shown in FIG. Torque converter 1
is a well-known type including a pump 5, a turbine 6, and a stator 7. The pump 5 is connected to an engine crankshaft 8, and the turbine 6 is connected to a turbine shaft 9. The turbine shaft 9 forms the output shaft of the torque converter 1, and also serves as the input shaft of the overdrive mechanism 2.
It is connected to the carrier 10 of the planetary gear device in the overdrive mechanism 2. A planetary pinion 14 (a planetary pinion 11) rotatably supported by a carrier 10
and meshes with the ring gear 15.

A multi-disc clutch 12 is located between the sun gear 11 and the carrier 10.
A one-way clutch 13 is provided, and a multi-disc brake 19 is provided between the sun gear 11 and a housing or overdrive case 16 containing the overdrive mechanism.

The ring gear 15 of the A-Budry 1 mechanism 2 is connected to the input shaft 23 of the gear transmission mechanism 3. A multi-disc clutch 24 is connected between the input shaft 23 and the intermediate shaft 29.
A multi-disc clutch 25 is provided between the input shaft 23 and the Zang gear shaft 30.

A multi-disc brake 26 is provided between the gear shaft 30 and the transmission case 18. Nan gear axis 3
The Zang gear 32 provided at 0 has a carrier 33, a planetary binion 371 carried by the carrier, a ring gear 35 meshing with the binion, another carrier 36, a planetary binion 37 carried by the carrier, Together with the ring gear 38 that meshes with the binion, a two-row planetary gear mechanism is constructed. The ring gear 35 in one of the planetary gear mechanisms is connected to the intermediate shaft 29. The carrier 33 in this planetary gear mechanism is connected to a ring gear 38 located next to the other planetary gear IIl, and the carrier and ring gear are connected to an output shaft 39. Further, a multi-disc brake 27 and a one-way clutch 28 are provided between the carrier 36 and the transmission case 18 in the other planetary gear mechanism.

Such an overdrive device (=lhydraulic automatic transmission) uses a hydraulic control system, which will be explained in detail below, to engage or release each clutch and brake according to the output of one engine and the vehicle speed. It is designed to perform four forward gear shifts including drive (0/D) or one reverse gear shift by manual switching.

Table 1 shows the shift gear position and operating status of clutches and brakes.
Shown below.

Table 1 Operating status of clutches and brakes Here, the ○ mark indicates the engagement of each clutch/brake, the Δ mark indicates the engagement when the vehicle is being driven from the engine side (released during engine braking), and the × mark indicates the disengaged state. (0/D)
indicates the overdrive position.

For forward movement, in D range 1st, 2nd, 3rd, 4th (0/
I)) automatic speed change operation is possible; in the 2nd range, automatic speed change operation of 1st speed and 2nd speed is possible; in the L range, the automatic speed change operation is fixed at 1st speed.

FIG. 2 is a diagram showing one embodiment of the speed change control device. Oil pumped up from the oil reservoir 40 by the oil pump 41 is sent to the line oil pressure control valve 42, and is sent to the oil line 43.
A line oil pressure P/ is generated which is regulated to a predetermined pressure.

This line oil pressure is also supplied to a manual switching valve 44, a throttle oil pressure control valve 45, and a detent oil pressure III valve 46.

The manual switching valve 44 is for parking (P), reverse (R),
Neutral (N), D range (D), 2 range (2>
, L range (L), and the line oil pressure supplied to its input port 43a is switched to its output boats 43b, 43c, 43d according to the switching position of the valve.
and 438 as shown in Table 2.

Table 2 The throttle hydraulic pressure control valve 45 generates a hydraulic pressure pth at its output port 50, which increases in accordance with the opening degree of the intake throttle valve at the depressed end of the accelerator pedal. The detent oil pressure control valve 46 regulates the line oil pressure to a lower predetermined oil pressure and generates detent oil pressure in its output oil path 51.The detent oil pressure is incorporated into the throttle oil pressure control valve and is activated when the accelerator pedal is depressed at a predetermined value or more. It is supplied to the transmission valves described below through a switching valve 52 and an oil passage 53 which are in communication with each other when the valve is turned on, and has the function of holding these valves at one switching position. Boat 43 of manual switching valve 44
The output oil passage 47 connected to b is connected to the clutch 24 (forward clutch), and the oil passage 47 a branched from the middle thereof is connected to the governor hydraulic control valve 54 . The governor oil pressure control valve generates governor oil pressure P (10) at its output port 55 in accordance with the vehicle speed.

56 and 57 are a 1st-2nd speed switching valve and a 2nd-3rd speed switching valve, respectively, and 58 is an overdrive control valve C.

The 1-2 speed switching valve 56 includes two valve elements 60 and 61 facing each other in the axial direction via a compression coil spring 59. The valve element 60 has the sum of the downward pressing force in the drawing exerted by the spring 59 and the downward pressing force in the drawing acting by the throttle oil pressure pth exerted on the boat 62 via the oil passage 50a, and the boat 63 at the lower end. Due to the balance with the upward pressing force in the figure given by the governor hydraulic pressure Poo applied through the oil passage 55a, the displacement occurs between the downwardly displaced position shown at 56A and the upwardly displaced position shown at 56B. It is now possible to do so. The valve element 61 is supplied to its boats 64 and 65 with the line hydraulic pressure that appears at its output port 43d when the manual switching valve 44 is switched to the low range, after being regulated through the oil line 49 and the low modulator valve 66. When such oil pressure is supplied, the valve element 61 is displaced downward in the figure, and serves to forcibly hold the valve element 60 below the vehicle speed at which it reaches the switching position 56A.

The 2-3 speed switching valve 57 similarly has valve elements 68 and 69 facing each other in the axial direction via a compression coil spring 67. The sum of the downward pressing force applied to the boat 70 via the pressure and the oil passage 501) and the throttle oil pressure applied to the boat 70 via the oil passage 501) and the oil passage 55b are the sum of the downward pressure applied to the boat 70 via the oil passage 501). Due to the equilibrium relationship with the upward pressing force, 1/JIM can be determined between the downward switching position shown at 57Δ and the upward switching position shown at 57B. Further, the line oil pressure that appears at the output port 430 when the manual switching valve 44 is switched to the 2nd range is applied to the upper surface of the upper valve element 69 via the oil passages 48 and 48a and the boat 72. The valve hair 169 is then displaced downwardly, forcing the valve element 68 in the downwardly switched position shown at 57A.

The overdrive control valve 58 has axially opposed valve elements 74 and 87 with a helical compression spring 73 in between. Furthermore, another valve element 88 is provided above the valve element 87. Valve element 74 is pressed downward in the figure by compression coil spring 73, while valve elements 87 and 88 are pressed upward in the figure by compression coil spring 73. An oil passage 5 is provided at the lower end of the valve element 74.
The governor hydraulic pressure PgO supplied to the boat 75 via 5G is applied. Further, a throttle oil pressure Pth is applied to the upper end of the valve element 87 via the oil passage 50C and the boat 77, and when this throttle oil pressure exceeds a certain value that overcomes the repulsive force of the compression coil spring 73, the Valve element 87 in the compressed state of the compression coil spring
directly engages with the valve element 74 and exerts a downward pressing force on the valve element 74 in the figure. Therefore, when the valve element 88 is biased toward its upper end as shown in the right half of the illustrated overdrive control valve, and the throttle oil pressure acting on the boat 77 is below the pressure that compresses the compression coil spring 73, the piston element 74 is a compression coil spring 7
Due to the balanced relationship between the downward spring force exerted by 3 and the governor hydraulic pressure acting on the boat 75, the switch is appropriately switched between the downward switching position shown at 58A and the upward switching position shown at 58B depending on the vehicle speed. It will be done. In addition, when the valve element 88 is biased to the upper end position in the figure, the thrower 1-hell hydraulic pressure acting on the boat 77 increases, compressing the compression coil spring 73 and bringing the valve element 87 into a state in which it is in direct contact with the valve element 74. <T, the valve element 74 moves the boat 77 with the downward pressing force in the figure due to the throttle oil pressure acting on the light C valve tether 87 and the boat 7
It is appropriately switched between the switching positions 58Δ and 58B depending on the balance of the upward pressing force in the figure due to the governor oil pressure acting on the controller 5. .

Line hydraulic pressure is supplied to the boat 78 of the 1st-2nd speed switching valve 56 via the oil passage 47I) when the manual switching valve 44 is switched to the D range. This line oil pressure is 1-2
When the speed changeover valve is in the upward switching position indicated by 56B, the oil is guided from the boat 79 to the boat 80 of the 2-3 speed changeover valve 57 via the oil passage 470. The line oil pressure led to the boat 80 is transferred from the boat 81 to the oil passage 47 when the 2-3 speed switching valve is in the downward switching position (not shown at 57A).
d to the brake 26 (second brake). Further, when the 2-3 speed switching valve is in the upward switching position as shown at 57B, the hydraulic pressure supplied to the boat 80 is guided to the boat 82, from where it passes through the oil passage 47e and the shuttle valve 47f to the clutch 25 ( reverse clutch).

Incidentally, when the manual switching valve 44 is switched to the 1-range, the oil pressure appearing on the output boat 43d is the boat 64 of the low modulator valve 66.1-2 speed switching valve 56,
It is supplied to the inside side of the brake 27 (first brake) via the boat 83 and the oil path 49a. still,
A manual switching valve 44 is located on the outside side of the brake 27.
The hydraulic pressure that appears on the output boat 43B when it is switched to the position is supplied.

The boat 84 of the overdrive control valve 58 is connected to the oil passages 43f and 43! from the oil passage 43! Line hydraulic pressure is supplied via. When the overdrive control valve is in the downward switching position as shown at 58A, the line oil pressure supplied to the boat 84 is supplied to the clutch 12 of the A-Patrive model through the boat 85 and the oil line 43 (+). , and when the overdrive control valve is to be switched upward as shown at 58B, the boat 86 and oil line 431
) to the brake 19 of the overdrive mechanism.

On the upper end face of the valve element 88 of the A-patribe i, II control valve 58 in the drawing, the line oil pressure that appears in the boat 43c when the manual switching valve is switched to the 2 or 1 position is connected to the oil passage 48.48b1. Shuttle valve 89 and boat 9
It is designed to be supplied through 0. Line hydraulic pressure is also selectively supplied to the boat 90 through another route passing through the solenoid valve 91 and the shuttle valve 89.

The solenoid valve 91 has a solenoid 92 and an armature 93.
, a compression coil spring 94, a valve boat 95 that is opened and closed by a valve element formed at the tip of the armature 93, an inlet boat 96, an outlet port 97, and a drain boat 98 communicating with the valve boat 95. When the solenoid 92 is not energized, the armature 93 is displaced downward in the figure by the action of the compression coil spring 94, and its tip closes the valve port 95. In this state, the line hydraulic pressure supplied to the inlet boat 96 via the oil passage 43J and the orifice 99 continues from the outlet port 97 through the oil passage 43k to the shuttle valve 89, and from there to the oil passage 4.
31 is supplied to the boat 90 of the overdrive control valve 58. On the other hand, when the solenoid 92 is energized,
Armature 93 is displaced upward in the figure against the action of compression coil spring 94, and valve ports 1-95 are opened. In this state, the line hydraulic pressure supplied to the inlet boat 96 via the oil passage 43J and the orifice 99 is applied to the valve boat 95.
The line hydraulic pressure is not effectively transmitted to the outlet boat 97 and the oil passage 43k following it.

A manual switch 1 is attached to the solenoid 92 of the solenoid valve 91.
Excitation current is selectively supplied from the electric arithmetic operation device 101 via the voltage 00. Electric computing device 1
01 is a medium-speed sensor 10 that uses an electric signal depending on the vehicle speed.
2 and a throttle sensor +J103 that generates an electric signal in response to the intake throttle opening lα.

Note that the throttle sensor 103 generates an electric signal in response to opening of the intake throttle.
The electric signal may be generated by directly detecting the opening degree of the intake throttle valve that is
As shown in the figure, it may be a device such as an oil pressure switch 104 that detects the detent oil pressure that appears on the boat 53 of the throttle oil pressure 11i1J all valve when the accelerator pedal is depressed beyond a predetermined amount.

The operating procedure of the speed change control device shown in FIG.
Except for the special operation of the electric control device including the solenoid valve 91, etc., which are related thereto, are generally well known, but in order to make the description of the present invention clearer, the operation of the hydraulic control circuit that is the basis thereof will be described here. A brief explanation will be given below.

When the D range manual switching valve 44 is switched to the D range, line oil pressure is supplied to the oil passage 47, and this line oil pressure is supplied to the clutch 24 as it is. At this time, when the vehicle is stopped or running at low speed, the governor oil pressure PQO generated by the governor oil pressure control valve 54 is low and 1-2.
The speed switching valve 56.2-3 speed switching valve 57 and overdrive control valve 58 are in the downward switching position as shown at 56A157A and 58A, respectively, and the hydraulic pressure supplied through the oil path 47b is shut off at the boat 78. Therefore, hydraulic pressure is not supplied to the reverse clutch 25 and second brake 26 that are connected to the subsequent oil passages. On the other hand, hydraulic pressure led to the overdrive control valve 58 from the oil passage 43f is supplied to the clutch 12 of the overdrive mechanism. Therefore, in this state, the overdrive mechanism is in a locked state and the gear transmission mechanism is in the first speed state.

When the vehicle speed gradually increases from this state, the governor oil pressure Po
o gradually increases, and at a certain vehicle speed, the 1st-2nd speed switching valve 56 is switched to the position 56B, and the line oil pressure is introduced to the boat 79, and this oil pressure is transferred to the boat 8 of the 2nd-3rd speed switching valve 57.
It is transmitted from 0 to 81, and is supplied to the second brake 26 through the oil path 47d, thereby engaging the second brake 26. In this state, the gear transmission mechanism is switched to the second speed state.

When the vehicle speed further increases, the 2nd-3rd speed switching valve 57 is also switched to the position 57B, and the hydraulic pressure supplied to the boat 80 is then transmitted to the boat 82, from which the oil passage 47
It is supplied to the reverse clutch 25 through the e1 shuttle valve 471, engages the clutch 25, and on the other hand brake 26
The hydraulic pressure acting on the oil passage 47d1 is discharged through the boat 81 and the re-drain boat 81a. In this state, the gear transmission mechanism is switched to the third speed (directly connected) state.

As vehicle speed increases further, the overdrive control valve 58 is also switched to position 58B, assuming that the boat 90 is not being supplied with hydraulic pressure, whereby the hydraulic pressure supplied to the boat 84 is replaced by the boat 85. boat 86
The oil path 43h is supplied to the light brake 19, and on the other hand,
The hydraulic pressure acting on the clutch 12 is discharged through the oil passage 43g and the boat 85 to the drain boat 85a. In this state, the overdrive mechanism 2 operates and an overdrive state is achieved.

The above has explained the switching changes that occur as the governor oil pressure increases due to an increase in vehicle speed, but of course, such switching changes are based on the balance between the governor oil pressure and the throttle oil pressure that act in opposition to the valve elements of each switching valve, as described above. The switching point changes not only depending on the vehicle speed but also on the amount of depression of the accelerator pedal. Conversely, when the vehicle speed decreases, the overdrive control valve 58.2 - 3rd speed switching valve 57.1 - 2nd speed switching valve 56 are sequentially operated from 58B to 5V.
8A, 57B to 57A, and 56B to 56A, and it is clear that the gear position changes accordingly.

When the 2-range manual switching valve 44 is switched to the 2-range, in addition to the output port 43b, a ?b? lII
FFb+ is generated, and the oil pressure is supplied to the boat 72 of the 2-3 speed switching valve 57 and the boat 90 of the overdrive control valve 58 through oil lines 48a and 4811, respectively, and these valve elements 69 and 74 are shown below in the figure. Forcibly press the
The 2-3 speed switching valve and the overdrive 7R, + control valve are forcibly held at switching positions 57A and 58A, respectively. Therefore, in such a state, the overdrive mechanism is held in a locked state, and the gear transmission mechanism operates only in the second speed or lower, that is, in the first speed or the second speed.

When the L-range manual switching valve 44 is switched to lunge, hydraulic pressure is also generated in the boat 43d, which flows through the low modulator valve 66 to the boat 64 of the 1st-2nd speed switching valve 56.
and 65, driving its valve element 61 downward in the figure and forcibly holding the 1-2 speed selector valve in the condition 56A. In this state, the automatic transmission mechanism is maintained at the first speed state.

Next, there is an electric control for electrically controlling the overdrive control valve 58, that is, the highest gear shift valve that achieves the highest speed gear among the shift valves! The II device will be explained. Third
The figure is a pictorial diagram showing an example of the logic circuit in the electric driver operating device 101 in FIG. 2. In this embodiment, the throttle sensor 103 is configured as a switch that detects whether the throttle opening exceeds 85%, and this switch detects kickdown of the accelerator pedal. It may be called a switch. Therefore, in the following description, this will be referred to as a kickdown switch.

The output a of the kickdown switch 103 is output when the throttle opening (T) does not reach 85% (T<85%), H(
When the throttle opening is 85% or more (1285%), it becomes 1-(low).

The output of the vehicle speed sensor 102 is the comparator 105 and 1
06. Comparators 105 and 106
A high-speed reference voltage X and a low-speed reference voltage Y are respectively input to the . The output C of the comparator 105 becomes L when the output voltage V that indicates the vehicle speed is equal to or smaller than the high-speed reference voltage X (V≦X), and when the voltage V is greater than the high-speed reference voltage X (V>X ). The high-speed reference voltage X is designed to take one of two values, V+ and Vi-ΔV+, depending on changes in throttle opening and vehicle speed. In this case, for example, V+L
;L 165km/h Thea VJ, ΔVt Ha 10kl
It may be l/h.

] In the comparator 106, the voltage V and the low-speed reference voltage Y are compared, and the output d is 1- when V≧Y.
When V<Y), it is set to -1. The low-speed reference voltage Y also changes due to changes in throttle opening and vehicle speed.
2 and v2-ΔV2. In this case, for example, v2 may be 65 kII/h, and Δv2 may be 20 kII/17/11.

Output a of kickdown switch 103, outputs C and dG of comparators 105 and 106, and tOR circuit 107
is supplied to. The output e of the OR circuit 107 becomes L when all of the human forces a, c, and d are L, and becomes (g) under other conditions. 108 is a solenoid drive circuit for driving the solenoid 92; When the human power is set to H, the solenoid 92 is energized and energized (O
). On the other hand, when the human power e is L, the solenoid drive circuit 108 does not supply current to the solenoid 92 and de-energizes it (turns it OFF). As is clear from this, when the throttle opening does not reach 85% (that is, when kickdown is not performed), the solenoid 92 is in the ON state regardless of the vehicle speed.

FIG. 4 is a graph showing the design value of the change in the high-speed reference voltage X with respect to the vehicle speed when the throttle opening is 85% or more, and the change in the output C of the comparator 105 with respect to the vehicle speed based on the design value. FIG. 5 is a graph showing changes in high speed reference voltage x and output C with respect to vehicle speed when the throttle opening is 85% or less or when kickdown is performed at a constant vehicle speed from that state.

Similarly, Figure 6 shows the gQ of low speed reference voltages n and Y for a vehicle speed of 1 when the throttle opening is 85% or above.
3 is a graph showing changes in gllfi and the output d of the comparator 106 based on the gllfi with respect to vehicle speed.

In addition, Figure 7 is a graph that does not show the changes in the low-speed reference voltage Y and output d with respect to the vehicle speed when the throttle opening is 85% or less or when kickdown is performed at a constant vehicle speed. be.

By combining these graphs, when kickdown is performed at a constant vehicle speed, the solenoid 92 will be in a state as shown in FIG. 8 depending on the vehicle speed at the time of kickdown. In other words, if the vehicle speed before kickdown is greater than vl-△V+ or less than V9, the solenoid that was previously in the ON state will remain in the ON state even after the kickdown.
When the vehicle speed is between Vp and Vl-Δv1, the solenoid that was previously in the ON state is turned OFF due to kickdown.

Further, when the vehicle speed changes while the throttle opening is 85% or more, the solenoid 92t is switched between ON and OFF with hysteresis as shown in FIG.

By switching the solenoid 92 as described above according to the vehicle speed, the overdrive control valve 58 is controlled in the high speed range.
As shown in FIG. 10, the shifting characteristics are corrected compared to when only the hydraulic control device is used. That is, the shift line section 1+-1-J in FIG. 10 is the modification of the upshift characteristic from 3rd gear to overdrive by the electric control device, and the shift line section -1-m is the correction of the upshift characteristic from 3rd gear to overdrive by the electric control device. This is a modification of the downshift characteristics from overdrive to third gear by the device. It will be understood that such modification ideally modifies the transmission characteristics in the high speed range for vehicles. By providing hysteresis in turning the solenoid ON and OFF at high speeds, frequent switching between 3rd gear and overdrive can occur due to changes in vehicle speed, for example on uphill roads. Prevented. In addition, the vehicle speed limit at which downshifting is prohibited when kicking down at high speed is set lower than when downshifting from low speed and increasing vehicle speed, so downshifting at high speed causes a large shift shock. occurrence is avoided.

Furthermore, in the above electric control all devices, low speed 1
14, in which the solenoid is held ON in a speed range in which gear changeover is performed only by the hydraulic control device. This is to prevent the solenoid from being turned OFF unnecessarily every time a 4-down occurs in such a low speed range. This greatly increases the durability of the solenoid valve 91. In addition, since hysteresis is given to the solenoid's 0N-OFF in this low speed range with respect to the vehicle speed,
There is no risk of hunting occurring in the solenoid near the N-OFF boundary. Furthermore, the control to keep the solenoid ON at low speeds is performed.
+ or higher) if a kickdown is performed while driving,
Downshifting can also be prohibited when a vehicle speed signal cannot be obtained due to a break in the speedometer cable or a malfunction in the vehicle speed sensor, preventing shift shocks caused by inadvertent downshifts at high speeds. .

FIGS. 11 and 12 are diagrams showing a more specific embodiment of the electric arithmetic operation device 101. FIG. FIG. 12 shows an IC incorporated in the circuit shown in FIG. 11, and this IC is shown in FIG. 11 with its terminal A-1 matching the terminal A-1 in FIG. This is incorporated into the circuit shown in .

When the vehicle is running, the reed switch of the vehicle speed sensor 102 is activated intermittently to generate a vehicle speed pulse signal. This vehicle speed pulse signal is input to a terminal of the IC 109, from which it is converted into a voltage signal V proportional to the vehicle speed by an F-V conversion circuit 110 incorporated in the IC, and is output to a terminal C. Resistors RB and R4 connected to terminal C are regulating resistors for voltage V. Terminal C is connected to a comparator 111 inside the IC, and is compared with a high-speed reference voltage X at the terminal divided by resistors R6, Ra, and R7. When V>X, the output at terminal F is It becomes L. A comparator 112 is further incorporated in the IC 109, and its input terminal G
is connected to the kickdown switch 103. Since the switch 103 is turned on during kickdown, the output of the comparator 112 becomes 1 to 1 at this time. The output stages of the comparators 111 and 112 are both oven collector ties/41 (and terminals F and G are connected to each other, so both outputs are all L except 11).

Terminal ■ is a power supply terminal for 10109, and terminal E is a ground terminal.

The transistors Tr+ and Tr2 constitute a low-speed side comparator. When the vehicle speed signal @V at the terminal C is lower than the low speed reference voltage Y, the collector of the transistor TrI and the base of the transistor Tr2 become I-1, and the base of the transistor TrQ becomes L. When V>Y, if the output at the terminal 1 is 1-1, the base of the transistor Tr8 becomes 1-1, and if the output at the terminal H is 1-1, the base becomes L. When the base of the transistor Tra is 1, the base of the transistor Tra is l-1, and the base of the transistor Tra is L. Transistor Tr
If the overdrive main switch 113 is ON when the base of , is 1-, the solenoid 92 is energized (ON).
state. Note that the diodes D+ and D2 are diodes for absorbing reverse voltage surges.

When the kickdown switch is OFF, that is, when it is not in the kickdown state, the output of the comparator 112 becomes L, and the output of the comparator 111, transistor Tr+ and TI
Regardless of the operation of 'fi, the base of the transistor Trs becomes the base, and the solenoid 92 is kept ON. At this point, the high-speed reference voltage
p.

When the kickdown switch is turned from OFF to ON at a constant vehicle speed, the following occurs.

First, when V<Vp, the terminal 1 becomes 1, but since the base of the transistor Tr2 becomes 1 to 1, the base of the transistor Tr8 becomes the base, and the solenoid 92 remains ON. At this time, the high-speed reference voltage
7 and rises to X=V+.

Since Vp<V<Vl-△VI, the base of terminal H, l-'7 transistor Tr2 is
The base of ra becomes H, and the solenoid is inverted to 0 (:).Then, the low-speed reference voltage Y is 1-transistor Tr.
Since the collector of a becomes a current and the potential of the emitter of transistor Tr+ decreases, it becomes Y-Vp-ΔV2.

When V>VI-ΔV+, the terminal H is L, so the transistor T
The base of rs becomes active and the solenoid remains on.

If the vehicle speed is increased or decreased in the kickdown state, the following will occur.

First, when kicking down when V<Vp, the solenoid remains ON and X=V+. Vehicle speed increases and Vp
When <V<VI, the base of the transistor Tr becomes low, the base of the transistor Tra becomes 1-1, and the solenoid 92 turns OFF. At this time Y
-V9-ΔV2.

When the vehicle speed further increases and v>VI, the terminal H becomes L and the base of the transistor Tra becomes 1-1.
The solenoid returns to ON again and becomes X = V + - ΔVl.

Next, on the pitching road, etc., the vehicle speed is V while still in the kickdown state.
> Consider the case where VI decreases.

Since X=V+-ΔV+r, the solenoid remains ON when V>Vl-ΔV+. v2-Δv2・guV<V
At I-Δv1, the solenoid is turned OFF, and X=V+
becomes. When the vehicle speed further decreases to V<Vp−Δv2, the solenoid 92 returns to ON again, and Y −V t
becomes.

It will be understood that with this configuration, ON-OFF operation of the solenoid as shown in FIGS. 8 and 9 can be obtained.

Although the present invention has been described in detail with respect to specific embodiments above, the present invention is not limited to such embodiments, and it is understood that various embodiments are possible within the scope of the present invention. It will be clear to those skilled in the art.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing an example of a hydraulic automatic transmission with an overdrive device. FIG. 2 is a schematic diagram showing an example of a shift control I device according to the present invention for the automatic transmission shown in FIG. FIG. 3 is a diagram showing the logical configuration of the electric arithmetic operation device incorporated in the transmission control device shown in FIG. 1. 4 to 9 are graphs illustrating the operation of the electric arithmetic operation device shown in FIG. 3. FIG. 10 is a shift diagram showing how the shift diagram is corrected by the shift IQ all device according to the present invention. FIG. 11 is an electric circuit diagram showing a more specific embodiment of the electric arithmetic operation device. FIG. 12 is a diagram showing IC elements incorporated into the electric circuit shown in FIG. 11. DESCRIPTION OF SYMBOLS 1... Torque converter, 2... Overdrive mechanism, 3... Gear transmission mechanism, 5... Pump, 6...
Turbine, 7... Stator, 8... Engine crankshaft, 9... Turbine shaft, 10... Carrier, 11...
・Sun gear, 12...Multi-plate clutch, 13...One-way clutch. 14... Planetary pinion, 15... Ring gear 7° 16... Overdrive case, 18... Transmission case, 19... Multi-disc brake, 23
...Input shaft of gear shifting m4H, 24.25...Multi-disc clutch. 26.27...Multi-disc brake, 28...One-way clutch, 29...Intermediate shaft, 30...Zan gear shaft,
31...Support, 32...Sun Gear, 33...
4 grin. 34...Planetary binion, 35...Ring gear. 36...Carrier, 37...Planetary Binion,
38...Ring gear, 39...Output shaft, 40...
Oil reservoir, 41...Oil pump, 42...
Line hydraulic control valve, 44...Manual switching valve, 45...
Throttle oil pressure control valve, 46... Detent oil pressure control valve, 47... D range output oil path, 48... 2 range output oil path, 49... Range output oil path, 52... Switching valve , 54... Governor hydraulic control valve, 56... 1-2 speed switching valve, 57... 2-3 speed switching valve, 58... Overdrive control piece, 66... Low modulator valve, 91
...Solenoid valve. 100... Manual switch, 101... Electric calculation operating device, 102... Vehicle speed sensor, 103... Throttle control J-, 104-... Oil pressure switch, 105.1
06... Comparator, 107... OR circuit, 10
8... Solenoid drive circuit, 109... IC element,
110...F-V conversion circuit, 111.112...Conditioner 1 < rater special r

Claims (1)

[Claims] An automatic transmission including a hydraulic torque converter and a gear transmission mechanism equipped with a plurality of frictional engagement devices for obtaining several gears is connected to a hydraulic power source and a line hydraulic pressure regulated from the hydraulic power source. The line hydraulic control valve generates throttle hydraulic pressure according to the intake throttle opening, the governor hydraulic control valve generates governor hydraulic pressure according to the vehicle speed, and the gear range is manually switched. a manual switching valve; a plurality of speed change valves that switch the hydraulic pressure supplied to the frictional engagement device according to the equilibrium relationship between the throttle hydraulic pressure and the governor hydraulic pressure; a vehicle speed sensor that generates an electric signal according to the vehicle speed; A throttle sensor that generates an electric signal depending on the intake throttle opening, and one end that is displaced depending on whether or not hydraulic pressure is selectively supplied to control whether or not to allow shifting to the highest speed gear. a solenoid valve that controls the supply of hydraulic pressure to the one end of the valve element; and an electrical calculation that controls energization of the solenoid valve based on electrical signals generated by the vehicle speed sensor and the throttle sensor. 1. A method of controlling a speed change using a speed change control device having an actuating device, the method comprising inhibiting a speed change to the highest speed gear when the throttle opening is equal to or greater than a relatively large predetermined value.