JPS60139958A - Control for automatic speed change gear - Google Patents

Abstract

PURPOSE:To prevent the knocking after shift-up by estimating the engine speed after the shift-up from the number of engine revolution within the range of low- speed ratio and performing shift-up when the estimated number of revolution is outside a knocking region. CONSTITUTION:In an automatic speed change gear in which a manual speed change gear 3 provided with 4-stages for advance and one-stage for retreat and a sub speed change gear 4 equipped with hydraulically driven high-speed and low-speed clutches 27 and 28 are integrally installed into a common case 5, and the high-speed clutch 27 is connected by the electric conduction to a solenoid valve 33 through a control circuit, and the low-speed clutch 28 is connected by deenergizing a solenoid valve 34, input and output revolution-angle sensors 37 and 38, an engine revolution-angle sensor, etc. are connected to the control circuit. When the speed change ratio is within the range of high-speed ratio in the control circuit, the number of revolution after the shift-up from the engine speed at that time to the high-speed ratio is estimated, and the solenoid valves 33 and 34 are controlled so that shift-up is performed when the estimated number of revolution is outside a knocking region.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for controlling an automatic transmission in a vehicle equipped with an internal combustion engine.

In automatic transmissions, when an upshift is performed from a low speed ratio to a high speed ratio during normal driving, the engine speed decreases, so depending on the engine speed just before the shift up, knocking may occur in the engine after the shift up, making driving difficult. It can be difficult.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a method for controlling an automatic transmission that prevents the occurrence of knocking after an upshift.

The automatic transmission control method of the present invention detects the engine speed when it is in a low speed ratio, predicts the engine speed after upshifting from the engine speed, and prevents the predicted engine speed from falling outside the knocking range. It is characterized by upshifting at certain times. .

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a power transmission system of an automobile to which the control method according to the present invention is applied.

In this figure, the rotational power generated by the engine 1 is transmitted to the wheels (
(not shown). Clamp 2, manual transmission 3
and the sub-transmission 4 are integrally formed by the case 5. The manual transmission 3 includes a clutch shaft 6, a counter shaft 7, a drive shaft 8, a clutch gear 9, and counter gears 10 to 14. Third speed gear 15, second speed gear 16, first speed gear 17,
It is a synchronous mesh type transmission with 4 forward speeds and 1 reverse speed, consisting of synchronizers 18 and 19, reverse gear 2°, etc.

The sub-transmission 4 includes a sun gear 21, a planetary carrier 22,
It is a planetary gear type two-stage automatic transmission using a planetary pinion 23 and a ring gear 24.

The sun gear 21 is rotatably provided on a drive shaft 8 which is the output of the manual transmission 3, and the planetary carrier 22 is fixed to the drive shaft 8 which is the input gear of the sub-transmission 4. A plurality of planetary pinions 23 meshed with the sun gear 21 are connected to a planetary carrier 22.
They are rotatable and are spaced apart from each other at regular intervals. A ring gear 24 meshed with each of the planetary pinions 23 is connected to the drive shaft 8 via a one-way clutch 25 and is fixed to an output shaft 26. The one-way clutch 25 is connected to the drive shaft 8
When the drive shaft 8 attempts to rotate beyond the rotational speed of the ring gear 24, a locked state occurs, and in this state, the drive shaft 8 and the ring gear 24 are connected. Further, the sub-transmission 4 has a high-speed clutch 27 and a low-speed clutch 28 which are hydraulically operated multi-plate clutches. When the high-speed clutch 27 is engaged, the high-speed clutch 27 fixes the sun gear 21 to the case 5 in pairs, and the rotational power of the drive shaft 8 is transmitted to the output shaft 26 via the planetary carrier 22, the planetary pinion 23, and the ring gear 24. The speed is increased and the gear ratio becomes a high speed ratio. Furthermore, when the low speed clutch 28 is engaged, the planetary carrier 22 and the ring gear 24 are connected to the low speed clutch 281.
The gears are directly connected to each other through the gears, and the gear ratio is set to a low speed ratio.

As shown in FIG. 2, pressure oil is supplied to the high-speed clutch 27 from a hydraulic source 30 via a hydraulic passage 31'ft, and to the low-speed clutch 28, pressure oil is supplied via a hydraulic passage 32 branched from the hydraulic passage 11!331. is supplied. A solenoid valve 33 is provided downstream of the branch point F of the hydraulic passage 31 to the hydraulic passage 32,
A solenoid valve 34 is also provided in the hydraulic passage 32. When the solenoid valve 330 solenoid 33α is de-energized, the valve body 31A
is moved to the left in the diagram by the biasing force of the spring 33C to close the hydraulic passage 31, and when the solenoid 33cL is energized, the valve body 33h resists the biasing force of the spring 33C and moves to the right in the diagram. In particular, the hydraulic pressure passage 31 is brought into communication. Further, when the solenoid 34α of the solenoid valve 34 is de-energized, the valve body 34b moves to the left in the figure by the biasing force of the spring 340 to communicate the hydraulic passage 32, and when the solenoid 34α is energized, the valve body 34b is moved by the spring 34C.
The hydraulic passage 32 is closed by moving to the right in the figure against the urging force of. Energization/de-energization of the solenoid valves 33, 34 is controlled by a control circuit 35, which will be described later.

As shown in FIG. 3, the control circuit 35 includes solenoid valves 33 and 34.
In addition, there is an engine rotation angle detection sensor 36 that is synchronized with the rotation of the camshaft of the engine 1 and generates an angular position signal with a period proportional to the rotation speed, and an engine rotation angle detection sensor 36 that is synchronized with the rotation of the camshaft of the engine 1 and generates an angular position signal with a period proportional to the rotation speed of the drive shaft 8. An input rotation angle detection sensor 37 that generates an angular position signal, an output rotation angle detection sensor 38 that generates an angular position signal with a period proportional to the number of rotations of the output shaft 26, and an opening degree of a throttle valve (not shown). A throttle opening sensor 39 that generates a corresponding output voltage is connected to the electromagnetic valve 40 that forcibly closes the throttle valve completely in order to reduce the engine speed. The engine rotation angle detection sensor 36, the input rotation angle detection sensor 37, and the output rotation angle detection sensor 38 are of a magnetic detection type consisting of a permanent magnet and a magnetic detection element.

The control circuit 35 includes waveform shaping circuits 51 to 53 which are provided corresponding to the rotation angle detection sensors 36 to 38 and shape the waveforms of the angular position signals into pulse signals, and the generation interval of the output pulses of the waveform shaping circuit 51. A pigeon counter 55 that measures the clock pulses counted by the engine and generates a digital signal representing the engine rotation speed, and a waveform shaping circuit 52.
The NIN counter 56 generates a digital signal representing the number of rotations of the drive shaft 8 by measuring all the clock pulses counted at the generation interval of the output pulse of the waveform shaping circuit 53, and the clock pulse counted at the generation interval of the output pulse of the waveform shaping circuit 53. N for measuring the rotation speed of the output shaft 26 and generating a digital signal representing the rotation speed of the output shaft 26. UT counter 57 and
A level correction circuit 59 that corrects the entire output level of the throttle valve opening sensor 39, an A/D converter 61 that converts the output voltage of the level correction circuit 59 into a digital signal, and a drive circuit 62 for each of the electromagnetic valves 33, 34, and 40. to 64, the CPU 65, various processing programs, and the sub-transmission 4
It consists of a 2ROM 66 and a RAM 67 in which the gear ratio, etc. of
OM66 and RAM67 are connected by a data bus line 68.

Further, the output pulse of the waveform shaping circuit 51 is supplied to the CPU 65 as an interrupt signal.

In such a configuration, the counters 55 to 57 indicate the engine rotational speed Ne1 and the rotational speed NI of the drive shaft 8.
The data of N and the rotational speed N0UT of the output shaft 26 are
Data on the throttle valve opening is supplied from the A/D converter 61 to the CPU 65 via a pass line 68.

The CPU 65 reads each of the above-mentioned data according to a calculation program stored in advance in the ROM 66, and determines whether the downshift condition or upshift condition of the sub-transmission 4 is satisfied based on the data. When the downshift condition is satisfied, a shift command signal is generated in the order of a high speed clutch off signal and a low speed clutch on signal, and when the upshift condition is satisfied, a low speed clutch off signal, a torque down on signal, and a high speed clutch are generated. A shift command signal is generated in the order of an on signal and a torque down/off signal.

The drive circuit 62 starts driving the solenoid valve 33 to open by energizing the solenoid 33α in response to the high-speed clutch-on signal. When the solenoid valve 33 is opened, pressure oil is supplied to the hydraulic source 3.
0 to the high-speed clutch 27 through the hydraulic passage 31 having a throttle 931α, and the high-speed clutch 27 is engaged. In addition, the drive circuit 62 stops driving the solenoid valve 33 to open in response to the high-speed clutch off signal, so that the pressure oil is restricted to 31h.
The high speed clutch 27 is released.

The drive circuit 63 operates the solenoid valve 34 by de-energizing the solenoid 34 (Lf) in response to the low-speed thalassotion signal.
The valve opening drive of the solenoid valve 34 is stopped and the solenoid valve 34 is fully opened. When the electromagnetic valve 34 is opened, pressure oil is supplied from the hydraulic source 8-30 to the low-speed clutch 28 through a part of the hydraulic passage 31 and the hydraulic passage 32 having the throttle 32af, and the low-speed clutch 28 is engaged. Further, the drive circuit 63 starts driving the solenoid valve 34 to close in response to the low-speed clutch off signal, so that the pressure oil is discharged through the throttle 32hf and the low-speed clutch 28 is released. The drive circuit 64 drives the solenoid valve 40 in response to the torque down on signal to close the throttle valve from the opening set by the driver to, for example, fully closed, and drives the solenoid valve 40 in response to the torque down off signal. The engine stops and the throttle valve returns to the opening set by the driver. Closing the throttle valve causes the engine rotational speed, that is, the rotational speed of the drive shaft 8 to decrease.

Therefore, during downshifting, the high speed clutch 27 is released and the low speed clutch 28 is engaged.

When upshifting, the low speed clutch 28 is first released, the engine speed is reduced, and the high speed clutch 27 is engaged.

Next, the procedure of the control method according to the present invention executed by the control circuit 35 will be explained according to the flow diagram of FIG.

In this procedure, first, the engine rotational speed N, the rotational speed N1N of the drive shaft 8, and the rotational speed N of the output shaft 26 are determined. UT, the throttle valve opening θthk is read (step 80), and then it is determined whether the gear ratio of the sub-transmission 4 is at a low speed ratio (step 81). This determination is made in part by the generation of the low-speed clutch on signal.
1 in the RAM 67, which is rewritten when the gear ratio becomes the low speed ratio and does not change until just before the low speed clutch off signal is generated to release the low speed clutch 28.
It is determined from the value of the shift flag using two address areas. In the case of a low speed ratio, it is determined whether the read engine speed Ne is greater than or equal to a predetermined engine speed NKNOCK (step 82).

The engine knocking characteristic is the engine rotation speed N.

and the throttle valve opening θth, and as shown in FIG. 5, the low engine speed portion where the engine speed is lower than the knocking limit rotation speed (solid line A) is the knocking region at the high speed ratio. If we show the knocking region at a high speed ratio by considering the gear ratio at a low speed ratio, the dashed line B in Fig. 2 is also a part where the engine speed is small, and the engine speed shown by the broken line B is the predetermined speed NKN.
It is ocK. That is, when the engine speed N is greater than the predetermined speed NKNocK at the low speed ratio, the vehicle can run without knocking even if the engine is shifted up to the high speed ratio.

Therefore, in the case of Ne≧NKNocK, the shift amplifier processing to the high speed ratio is performed by generating the low speed clutch off signal and the high speed clutch on signal (step 8).
3). On the other hand, if Ne < NKNOCK, knocking occurs when the gear is shifted up, so the vehicle continues to drive at a low speed ratio.

If it is determined in step 81 that the low speed ratio is dangerous, the speed ratio is the high speed ratio and continues in that state.

Note that in the embodiment of the present invention described above, step 8
Determination of low □ speed ratio in 1 All low speed clutch 11- This was done based on the occurrence of shift command signals such as switch-on signals, but it can also be determined by detecting the vehicle speed and engine speed and dividing the vehicle speed by the engine speed. good.

In addition, it was determined whether or not the detected engine rotation speed N at the low speed ratio was greater than the predetermined rotation speed NKNocK, which was obtained by multiplying the detected engine rotation speed N by the gear ratio at the high speed ratio. It is also possible to determine whether the rotational speed is higher than the rotational speed indicated by -A in FIG. 5 or not. □ In Figure 5, the engine speed for determining the knocking region in two steps relative to the throttle valve opening is shown, but in order to more closely approximate the knocking characteristics of the actual engine, it is possible to change the knocking region by three or more steps or continuously. Of course, it is also good as a discrimination engine speed.

□In this way, according to the automatic transmission control method of the present invention, the i
The engine speed after shifting to the other high speed ratio is predicted from the same engine speed at the same speed, and when the predicted engine speed is outside the knob keying range, the shift is performed. The engine speed is prevented from being within the knocking range. Therefore, smooth driving is maintained even after shifting up.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing the power transmission system of an automobile according to the present invention, and FIG. 2 is a hydraulic circuit for high-speed and low-speed clutch wandering in the power transmission system of FIG. i3' is a schematic configuration diagram, Fig. 3 is a block diagram showing the control circuit of the auxiliary transmission in the power transmission system of Fig. '1, and Fig. 4 is an operational flow of the surface control circuit showing the control method using misfire i. 0. Explanation of symbols of main parts 1...Engine 2...Clutch 3...Manual transmission 4...Sub-transmission 6...・Clear・・Chishi: Yaft 8...Drive shaft -゛21...Sun gear ' □ 22...Planetary brake'' Kiria 23...Planetary pinion 24...Ring gear 25...One-way clutch 26
...Output shaft 27...High speed clutch 28...
・Low speed clutch 31.32...Hydraulic passage 33.34
．． 40... Solenoid valve 35... Side circuit applicant Honda Motor Co., Ltd. agent Patent attorney Motohiko Fujimura 15- 〈 4 @ □ , ``1'' Kuso □ ′- ′, ″ □ , ゛352-”: Vero-All #-5

Claims (4)

[Claims] (1) A method for controlling an automatic transmission that is supplied with rotational power by an on-vehicle internal combustion engine and has at least two gear ratios, wherein the engine rotational speed is controlled when the gear ratio is at least one of the two low speed ratios. detecting the engine speed and predicting the engine speed after upshifting to the other high speed ratio of the transmission ratio, and shifting up to the high speed ratio when the predicted engine speed is outside the knocking range. A control method characterized by performing the following. (2) The control method according to claim 1, wherein the knocking region is set according to a signal representing engine load. (3) The control method according to claim 2, wherein the knocking region is a low engine speed range that is set according to the throttle valve opening of the engine and the engine speed. (4) The control method according to claim 3, wherein the knocking region includes a higher engine rotational speed when the throttle valve opening is small than when the throttle valve opening is small.