JPS61249841A - Electronic control transmission for automobile - Google Patents

Abstract

PURPOSE:To make an engine brake appliable with a shift step at the time of acceleration, by making the shift step in the existing driving state so as to be maintained at a time when an accelerator is suddenly put back where it was, during acceleration. CONSTITUTION:This transmission is provided with a maximum speed shift step judging device (b) which receives an output signal out of a shift step detecting device (a) detecting a shift step in the existing driving state and judges of whether the shift step is a maximum speed shift step or not, an accelerator opening variation detecting device (d) which receives an output signal out of an accelerator opening detecting device 9c) and detects a fact that accelerator opening is varied to being less than the setting value from a state of being more than this value, an accelerator opening variation measuring device 9e) which measures a variation in the accelerator opening, an accelerator opening variation judging device (f) which judges of whether an accelerator opening variation is more than the specified value of not, and a holding device (g) which maintains the existing driving shift step when the shift step is out of the maximum speed shift step and the accelerator opening variation is less than the setting value.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an electronically controlled automatic transmission for automobiles, and more specifically, the present invention relates to an electronically controlled automatic transmission for automobiles, and more specifically, it is installed in an automobile and changes the transmission path of engine output according to the driving condition. The present invention relates to an automatic transmission that automatically changes gears.

(Prior art) Automatic transmissions for automobiles that use a planetary gear mechanism are generally used, but when an attempt is made to increase the number of gears for a truck, etc., a system that uses a planetary gear mechanism is used. The structure of the gear train becomes significantly more complex, and the entire transmission becomes larger. Therefore, we adopted the gear train structure conventionally used in manual transmissions, in which multiple gear trains with different gear ratios are arranged in parallel between two parallel axes, and one of these gear trains is selectively set to a power transmission state. Automatic transmission uses a gear train that obtains multiple gears by using a friction clutch, and automatically switches gears using a shift map by selecting the gear train using a friction clutch. It is possible to adopt a machine.

The shift map that automatically changes the gears mentioned above is as follows:
For example, a 1-2 shift line T1 and a 2-3 shift line T2 are determined based on the accelerator opening-vehicle speed characteristics as shown in FIG.
．． 34 transmission line T3 is generally used. However, when changing gears according to this shift map, if deceleration is required during acceleration, if the brake is applied and the accelerator is released, the accelerator opening becomes smaller, resulting in an upshift, and the next There is a problem with poor responsiveness when accelerating.

There is also the problem that engine braking is not effective due to upshifting like this.

Therefore, in the automatic transmission disclosed in Japanese Unexamined Patent Publication No. 59-100023, the above-mentioned problem is solved by detecting the operation of the brake and inhibiting upshifting when the brake is applied.

(Object of the Invention) The present invention provides an electronically controlled transmission for an automobile that solves the above-mentioned problems by a method different from the above-mentioned prior art.

(Structure of the Invention) The present invention is an electronically controlled transmission for an automobile that automatically controls gear stages from low speed to high speed by electronic control means,
A gear position detection means a for detecting the gear position in the current running state; and a highest speed gear position determination means for receiving an output signal from the gear position detection means a and determining whether or not the gear position is the highest gear position. Then, the accelerator opening detecting means C detects the accelerator opening and receives an output signal from the accelerator opening detecting means C, and detects that the accelerator opening has changed from the set value or more to the set value or less. Detecting accelerator opening change detection means d
When receiving the output signal of the accelerator opening change detection means d, the accelerator opening change rate measuring means e measures the change rate of the accelerator opening degree, and the output signal from the accelerator opening change rate measuring means e. an accelerator opening change rate determination means f for determining whether or not the accelerator opening change rate is equal to or higher than a predetermined value; The present invention is characterized in that it includes a holding means g for holding the currently running gear position.

(Operations and Effects of the Invention) In the electronically controlled transmission for automobiles of the present invention having the above-described configuration, when the accelerator is suddenly released during acceleration, the gear position in the current driving state is maintained, so that the gear position in the current driving state is maintained. It is possible to do this without applying engine braking in the current gear position, and the acceleration response when the accelerator is fully depressed is improved.

(Example) Hereinafter, an electronically controlled transmission for an automobile according to a preferred example of the present invention will be described with reference to the accompanying drawings.

As shown in FIG. 3, the automatic transmission 1 includes an input shaft 10, which is housed in a mission case 2 and whose front end is connected to an engine output shaft 3 via a flywheel 4 and a buffer disc 5. An output shaft 20 which is arranged coaxially at the rear and to which a propeller shaft (not shown) is attached to the rear end is connected to the drum 6, and a counter shaft 30 which is arranged parallel to these shafts 10, 20. These shafts 10.2
The structure includes multiple gear trains, friction clutches, one-way clutches, etc. that transmit and cut off power within 0.30 mm.

The input shaft 10 has a first gear 4 in the middle part.
1 is loosely fitted to the countershaft 30, and a second gear 42, which is always in mesh with the gear 41, is spline-fitted to the front part of the countershaft 30, and these gears 41 and 42 constitute a first gear train I. There is. and input shaft 1
A wet multi-plate first friction clutch 51 is provided on the shaft 10 to connect and separate the shaft 10 and the first gear 41. This first friction clutch 51 is connected to the input shaft I
A drum 51a spline-coupled to O, a hub 51b integrally formed with the first gear 41, and a plurality of friction plates 51c disposed between the two and alternately spline-fitted to the drum 51a and the hub 51b. and these friction plates 51. when the working pressure is introduced. C is fastened to the drum 51a.
In other words, the hub 51b1 includes a piston 51d that connects the input shaft 10 and the first gear 41.

Further, a third gear 43 is fitted to the rear end of the input shaft 10 via a one-way clutch 61, and a fourth gear 44, which is always in mesh with the gear 43, is loosely fitted to the counter shaft 30. These gears 43 and 44 constitute a second gear train (2). The shaft 30 and the fourth gear 4 are disposed on the counter shaft 30.
A second friction clutch 52 is provided for coupling and separating the countershaft 30 and the countershaft 30.
and a hub 52b connected to the sleeve-like extension 44a of the fourth gear 44.
A plurality of friction plates 52c are disposed between the drum 52a and the hub 52b, and when operating pressure is introduced, these friction plates 52c are fastened to connect the drum 52a and the hub 52b1, that is, the countershaft 30 and the fourth The piston 52b is connected to the gear 44.

Further, a third friction clutch 53 is disposed between the one-way clutch 61 at the rear end of the input shaft 10 and the front end of the output shaft 20.

This clutch 53 also includes a drum 53a spline-coupled to the output shaft 20, a knob 53b integrated with the outer race 61a (third gear 43) of the one-way clutch 61, and a plurality of friction elements arranged between the two. It is composed of a plate 53c and a piston 53d that fastens these friction plates 53c and connects the hub 53b and drum 53a when operating pressure is introduced. Then, this third friction clutch 53 is engaged, and the one-way clutch 6
1 is locked, the input shaft 10 and the output shaft 20 are coupled. Here, an engine brake friction clutch 56 is provided on the input shaft 10 in parallel to the one-way clutch 61. This clutch 56 includes a drum 56 splined to the input shaft 10.
a, a hub 56b integral with the outer race 61a of the one-way clutch 61, a plurality of friction plates 56C disposed between these, and a piston that connects the friction plates 56C to connect the drum 56a and the hub 56b. 56d. Therefore, when this friction clutch 5G is engaged, the input shaft 10 and the third gear 43 to the hub 53b of the third friction clutch 53 are coupled even if the one-way clutch 61 is in a free state.

On the other hand, a fifth gear 4 is provided at the rear of the countershaft 30.
A sixth gear 46, which always meshes with the gear 45, is loosely fitted to the output shaft 20, and these gears 45 and 46 constitute a third gear train (2). A fourth friction clutch 54 is disposed on the output shaft 20 to connect and disconnect the shaft 20 and the sixth gear 46. This fourth friction clutch 54 is connected to the drum 53 of the third friction clutch 53.
a drum 54a integrally formed with the output shaft 20 and spline-coupled to the output shaft 20; a hub 54b integral with the sixth gear 46; and a plurality of friction plates 54c disposed between the drum 54a and the hub 54b. When the working pressure is introduced, the # diaphragm 54C is fastened to the drum 54a and the hub 54b1.
That is, the piston 54d connects the output shaft 20 and the sixth gear 46.

Furthermore, a seventh gear 47 is provided at the rear end of the countershaft 30.
are spline-fitted to each other, and an eighth gear 48 that constantly meshes with the gear 47 is loosely fitted to the output shaft 20, and these gears 47 and 48 constitute a fourth gear train (2). A fifth friction clutch 55 is disposed at the rear of the output shaft 20 to couple and separate the shaft 20 and the eighth gear 48. This clutch 55 also includes a drum 55a spline-coupled to the output shaft 20, a hub 55b integrated with the eighth gear 48, and a plurality of friction plates 55c disposed between the drum 55a and the hub 55b. When the working pressure is introduced, these friction plates 55c are fastened to connect the drum 55a and the hub 55b1.
That is, it is composed of a piston 55d that connects the output shaft 20 and the eighth gear 48.

Here, the one-way clutch 61 locks when the rotational speed of the input shaft (inner race) 10 is about to become larger than the rotational speed of the outer race 61a in a predetermined rotational direction, and transmits the rotation of the input shaft IO to the outer race 61a. However, when the rotational speed of the outer race 61a exceeds the rotational speed of the input shaft 10, it idles. Further, the first gear train I has a gear ratio of approximately 1, and the second gear train (I) has a gear ratio of approximately 1, and the second gear train (2) has a gear ratio of approximately 1.
The third gear train ■ is decelerated when the rotation is transmitted from the fifth gear 45 to the sixth gear 4, and the fourth gear train ■ is decelerated when the rotation is transmitted from the fifth gear 45 to the sixth gear 48. The diameter of each gear 41 to 48 is set so that the gears 41 to 48 are decelerated at a larger reduction ratio than the third gear train (2) when transmitting the rotation.

Further, the fifth friction clutch 55 disposed at the rear of the output shaft 20 is connected to the other friction clutches 51 to 54.
．． 56, and is arranged at a position rearward from the rear end of the countershaft 30 so as not to interfere with the countershaft 30.

In addition to the above configuration, a reverse speed gear train V is provided between the counter shaft 30 and the output shaft 20. This gear train ■ has a countershaft 30
, an idle gear 73 on an idle shaft 72 that constantly meshes with the gear 71, and a driven gear 74 that is loosely fitted on the output shaft 20 that constantly meshes with the gear 73. has been done. and,
A spline 75 is formed on the output shaft 20, and a spline 74a of the same shape is formed adjacent to the spline 74a on the side surface of the driven gear 74, and a sleeve is slidably fitted onto the former spline 75. 76 is fitted across both splines 75.74a by a shift fork 77, so that the driven gear 74 is coupled to the output shaft 20.

Further, in this embodiment, a parking gear 81 is fixedly installed on the outer periphery of the drum 55a of the fifth friction clutch 55.
When the parking pole 82 is engaged with the gear 81, the output shaft 20 is fixed via the drum 55'a.

Further, a power take-off gear 84 supported on the shaft 83 is meshed with the fourth gear 44 on the counter shaft 30.
Power is extracted from the gear 84 for use in various operations other than driving the vehicle.

Next, the power transmission state at each gear stage of the automatic transmission will be explained using the clutch operation table shown in Table 1 and the outline diagrams shown in FIGS. 4 to 8. Here, in Table 1, the O mark is Ff! For friction clutches, this indicates the engaged state, and for one-way clutches, it indicates the locked state. Further, the mark (0) indicates a state in which the connection is made but does not participate in power transmission.

First, in the first speed, as shown in Table 1, the second friction clutch 52 and the fifth friction clutch 55 are engaged, and the one-way clutch 61 is in a locked state. At this time,
The output rotation of the engine is as shown by the shaded area in Fig. 2.
The signal is transmitted from the input shaft 10 via the one-way clutch 61 to the third gear 43 of the second gear train (2), and is further input from the fourth gear 44 via the second friction clutch 52 to the countershaft 30. The cough countershaft 30 is further connected to the output shaft 20 via the 7.8th gear 47.48 constituting the fourth gear train (2) and the fifth friction clutch 55.

In this case, the rotation of the input shaft 10 is decelerated by the second gear train (2), and is also greatly decelerated by the fourth gear train (2) and transmitted to the output shaft 20, so that a first speed state with a large reduction ratio is obtained.

Next, when shifting from 1st speed to 2nd speed, the first friction clutch 51 is newly engaged in the above-mentioned 1st speed state as shown in Table 1. At this time, as shown in FIG. 5, the rotation of the input shaft 10 is input from the first friction clutch 51 to the counter shaft 30 via the first and second gears 41 and 42 that constitute the first gear train I. At the same time, the rotation is transmitted from the countershaft 30 to the output shaft 20 via the seventh and eighth gears 47, 48 of the fourth gear train (2) and the fifth friction clutch 55, as in the first speed. In this case, the reduction ratio of the first gear train T is approximately 1, which is smaller than the reduction ratio of the second gear train (3) that transmits rotation from the input shaft 10 to the countershaft 30 in the first gear. Reduction ratio is smaller than 1st speed 2
A state of speed is obtained.

Note that the shift from 1st to 2nd gear is performed only by the engagement operation of the first friction clutch 51 as described above, and the second friction clutch 52, which was engaged during 1st gear, remains engaged even after shifting from 1 to 2. It is in a contracted state.

Therefore, as shown by dotted lines in FIG. 3, the rotation transmitted to the countershaft 30 is transferred from the second friction clutch 52 to the fourth
It is transmitted to the gear 44 through the third gear 43, but in this case, the one-way clutch 61 between the third gear 43 and the in-button shaft 10 is in an idling state because the outer race 6] and the a side rotate at high speed. Therefore, rotation is not transmitted from the input shaft 10 to the countershaft 30 via the second gear train (2).

Further, when shifting from second speed to third speed, the fourth friction clutch 54 is newly engaged from the second speed state, and the fifth friction clutch 55 is released, as shown in Table 1. Therefore, as shown in FIG. 6, 100 revolutions of the input shaft are transmitted from the first friction clutch 51 to the counter shaft 30 via the first and second gears 41 and 42 of the first gear train I, and The signal is transmitted from the shaft 30 to the output shaft 20 via the fifth and sixth gears 45 and 46 of the third gear train (2). In this case, the reduction ratio of the third gear train ■ is smaller than the reduction ratio of the fourth gear train ■, which transmits rotation from the counter shaft 30 to the output shaft 20 at the time of 1.2 speed, so the reduction ratio of the third gear train The state is obtained. In this case as well, since the second friction clutch 52 is engaged, the rotation of the countershaft 30 is transmitted to the outer race 61a of the one-way clutch 61, but since the one-way clutch 61 is idling, the second gear train The rotation of the input shaft 10 and the rotation of the counter shaft 30 do not interfere with each other. and,
The second friction clutch 5 is activated at an appropriate time after shifting to third gear.
2 is released.

In addition, as shown in Table 1, shifting from 3rd to 4th speed is as follows:
From the third speed state (the state in which the second friction clutch 52 is already released), the third friction clutch 53 is engaged, the fourth friction clutch 54 is released, and the one-way clutch 61 is locked. Therefore, as shown in FIG. 7, the rotation of the input shaft 10 is transmitted from the one-way clutch 61 to the output shaft 20 via the third friction clutch 53. In this case, input shaft 1 does not pass through any gear train.
0 rotation is directly transmitted to the output shaft 20,
A so-called 4-speed direct connection state is obtained. In this case, the first friction clutch 51, which was engaged during the third gear, remains engaged. Therefore, as shown by the dotted line in FIG. However, since the clutch 55 is released, the rotation is not transmitted from the counter shaft 30 to the output shaft 20.

Further, when shifting from 4th speed to 5th speed, the second friction clutch 52 is further engaged from the 4th speed state, as shown in Table 1. Therefore, as shown in FIG. 8, the rotation of the input shaft 10 is input from the first friction clutch 51 to the countershaft 30 via the first and second gears 41 and 42 of the first gear train (2). Furthermore, a second friction clutch 5
2 to the output shaft 20 via the fourth and third gears 44, 43 of the second gear train (2), and the third friction clutch 53.
transmitted to. In this case, the rotation transmission from the counter shaft 30 to the output shaft 20 is 1
．． This is done via the second gear train (2) instead of the fourth gear train (2) at second speed or the third gear train (3) at third speed. At this time, the second gear train
The rotation speed is increased by transmitting the rotation from the third gear 43 to the third gear 43 having a smaller diameter. As a result, a so-called 5th speed in an overdrive state is obtained. in this case,
The one-way clutch 61 idles for the same reason as when in second gear.

As described above, the four gear trains ■ to ■ arranged in parallel between the two parallel shafts are selectively put into the power transmission state by the operation of the five friction clutches 51 to 55 and the one-way clutch 61. This results in two forward gears. Then, each of the 1-2 and 4-5 speed changes is performed by operating only one friction clutch.

Further, the fifth friction clutch 55, which transmits power together with the fourth gear train (2) at the 1st and 2nd speeds, requires a large torque capacity. Since the shafts 20 and 30 are arranged in the same direction, a sufficient diameter can be secured without increasing the distance between the shafts 20 and 30. Therefore, there is no need to increase the number of friction plates 55c.

In addition, the one-way clutch 61 locks and transmits power in 1st and 4th gears, but the output shaft 20
During coasting of a car where driving force is input from the side, the one-way clutch 61 idles and the automatic transmission 1
becomes a neutral state. Therefore, when applying the engine brake during coasting, the engine brake friction clutch 56 arranged in parallel with the one-way clutch 61 is engaged as shown in Table 1, and the power is applied in place of the one-way clutch 61. introduce. Therefore, in this case as well, a predetermined gear position is obtained and the engine brake is activated.

Further, during the reverse speed, the one-way clutch 61 is locked, the second friction clutch 51 is engaged, and the driven gear 74 of the reverse speed gear train 2 is coupled to the output shaft 20 via the sleeve 76. Because of that,
The rotation of the input shaft 10 is controlled by the one-way clutch 6
1, the second gear train (2), the second friction clutch 52, the counter shaft 30, and the reverse speed gear train (2) are transmitted to the output shaft 20. , the direction of rotation of the output shaft 20 is reversed.

The above speed change operation is achieved by selectively operating the first to fifth friction clutches 51 to 55 in accordance with Table 1 above by an electronic control circuit 100 constituted by, for example, a microcomputer.

The electronic control circuit 100 includes an input/output device 101, a random access memory (hereinafter referred to as RAM) 102, and a central processing unit (hereinafter referred to as CPU) as shown in FIG.
) 103. The input/output device 201 detects the throttle opening and outputs a throttle opening signal Sα.
A throttle opening sensor 104 that outputs a vehicle speed, a vehicle speed sensor 105 that detects the vehicle speed and outputs a vehicle speed signal Sv, and a gear position sensor 106 that detects the gear position of the current driving state and outputs a gear position signal Ss are connected, The input/output device 101 is configured to manually input the signals and the like from these sensors and the like.

The input/output device 201 processes the throttle opening signal Sα', the vehicle speed signal Sv, and the gear position signal Ss received from the sensor and supplies them to the RAM 102.

The RAM 102 stores these signals Sα, SV, and SS, and also stores these signals Sα, 5vSSS, or other data in response to instructions from the CPU 103.
PU 103 is supplied. CP0103 outputs the vehicle speed signal S according to a program compatible with the shift control of the present invention.
v and throttle opening signal Sα are compared with a shift map having shift lines TI, T2, and Ta determined based on the vehicle speed-throttle opening characteristic as shown in FIG. 1 to determine whether or not to shift. Perform the calculation.

The calculation result of the CPU 103 is given via the input/output device 101 as a signal for controlling the excitation of a group of electromagnetic valves 107 of a hydraulic control circuit that selectively controls the operation of the clutch. Through the above steps, upshift or downshift control is performed.

In the above-mentioned shift control, when the accelerator opening becomes small while the vehicle is running at a constant speed, the gear is generally shifted up. However, as mentioned above, if you suddenly decelerate during acceleration and then accelerate again immediately after that, the accelerator opening will be small during the sudden deceleration, or even if it is fully open. , it is desirable to maintain the gear position in the current driving state. Therefore, in the present invention, the gear position holding mechanism 110 is provided in the transmission, and when the electronic control circuit 100 determines that a sudden deceleration has occurred during the above-mentioned acceleration, the gear position holding mechanism 110 is
0 is activated to maintain the gear position in the current driving state.

Next, with reference to FIG. 10, one mode of control of gear position holding by the electronic control circuit 100 will be described.

This gear position holding control is performed by first reading out the gear position, that is, the position of the gear position. Next, based on the read gear position, it is determined whether the current gear position is the fifth gear, which is the highest gear position. When the vehicle is in fifth gear, it is not possible to shift up, so high-speed control is performed using a normal shift map. If the fifth speed is not possible, the accelerator opening degree α is read out, and it is determined whether the accelerator opening degree α is 4 or more of the full throttle opening degree αFULL, that is, whether or not acceleration is being performed. If this determination is YES, α is stored and then the shift-up speed change control is performed.

On the other hand, when the determination of α>αFtlLL is No, it is determined whether α in the previous control routine was 2αFLILL, and it is determined whether this determination is YBSO°C. This set value is set to be slightly larger than the rate of change in the accelerator opening when the driver takes his foot off the accelerator pedal and the accelerator opening becomes zero.

Based on the above multiple determinations, it is determined whether sudden deceleration has occurred during acceleration, and if the determination is YES, a signal is output to hold the current running gear, that is, the gear position. If this determination is No, it is not necessary to hold the gear position, so the gear change control is performed using the shift map.

To hold the above gear, turn the accelerator switch ON again.
It continues until it reaches the ON state, and when it reaches the ON state,
Release the hold and perform upshift control.

According to the above-described hold control of the gear position in the current driving state of the present invention, a shift-up is not performed by a sudden off-operation of the accelerator in the case of sudden deceleration during acceleration. There is no shifting, making it easier to drive.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an example of a shift map used in an automatic transmission, FIG. 2 is a block diagram showing the structure of the automatic transmission of the present invention, and FIG. 3 is an automatic transmission according to an embodiment of the present invention. Figures 4, 5, 6, 7, and 8 are diagrams showing the gear transmission mechanism of the machine, respectively. Figure 9 is a schematic diagram of the gear train showing the power transmission path of each gear stage. FIG. 10, which is a block diagram of the control system, is a flowchart showing an example of the control for maintaining the gear position in the current running state. 1... automatic transmission, a... gear stage detection means, b.
...Maximum speed gear stage determination means, C...Accelerator opening detection means, d...Accelerator opening change detection means, e...Accelerator opening change rate measuring means, f...Accelerator opening change Rate determining means, g...Holding means Vehicle speed V Fig. 2 Fig. 9 Choice 0 Treetop 7 Fig. 8

Claims (1)

[Claims] An electronically controlled transmission for automobiles that automatically controls shift positions from low speed to high speed by electronic control means,
a shift position detection means for detecting the shift position in the current driving state; a maximum speed range determination means for receiving an output signal from the shift position detection means and determining whether the shift position is in the highest speed range; an accelerator opening degree detection means for detecting the accelerator opening degree, and an accelerator opening degree change detection device that receives an output signal from the accelerator opening degree detection means and detects that the accelerator opening degree has changed from a state above a set value to below the set value. an accelerator opening change rate measuring means for measuring a rate of change in the accelerator opening when receiving an output signal from the accelerator opening change detecting means; , an accelerator opening change rate determining means for determining whether or not the accelerator opening change rate is equal to or higher than a predetermined value; An electronically controlled transmission for an automobile, comprising a holding means for holding a running position.