JP2985498B2 - Shift engagement time measuring device for hydraulic automatic transmission - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[Industrial application] As a vehicle equipped with a hydraulic automatic transmission is accelerated, the governor pressure rises and the first gear → 2
The speed is changed in the order of speed → third speed → fourth speed. At this time, for example, when shifting from the first gear to the second gear, a time is required between the start of shifting to the second gear and the completion of shifting to the second gear. The present invention relates to a device for measuring this time, that is, the shift engagement time.

[0002]

2. Description of the Related Art The shift engagement time can be used as one of the evaluation items of a hydraulic automatic transmission. In order to measure the shift engagement time, the shift engagement time is transmitted when the actual vehicle is accelerated to the input shaft of the hydraulic automatic transmission (the shaft to which the torque from the engine is input when mounted on the vehicle). While transmitting the torque, a technique for measuring the shift engagement time while applying a load generated when the actual vehicle is accelerated to an output shaft (an axis associated with wheels when mounted on a vehicle) is known. Have been.

In the prior art, A. From the timing at which the rotation speed ratio (output shaft rotation speed / input shaft rotation speed) exceeds the rotation speed ratio at the low speed stage to the timing at which the rotation speed ratio reaches the high speed stage. Detect the time difference of
Or B. The torque transmitted to the output shaft pulsates temporarily,
Next, the time difference until the torque level in the high-speed stage is reduced is detected.

[0004] Further, instead of reproducing and measuring the actual vehicle acceleration state, Japanese Patent Application Laid-Open No. 63-168531 discloses a method of adjusting the governor pressure by a hydraulic circuit. However, this publication does not disclose any specific technique for measuring the shift engagement time. In addition, Japanese Patent Application Laid-Open No. Sho 62-106340 discloses that an operator shifts a lever in the "P (parking)" or "N (neutral)" range to the "R (reverse)" or "D (drive)" range. A technique for detecting a time from when the switching is performed to when the torque starts to be transmitted to the output shaft is introduced.

[0005]

The technique A detects the time required for the rotational speed ratio to switch from the rotational speed ratio at the low speed stage to the rotational speed ratio at the high speed stage. However, the automatic transmission has a built-in torque converter, and the speed ratio is affected by the magnitude of the slip generated in the torque converter. For this reason, the above-mentioned time is not necessarily the shift engagement time, and different times are measured depending on the magnitude of the slip generated in the torque converter although the automatic transmission has the same shift engagement time.

The technique B is intended to measure the shift engagement time from the state of torque fluctuation occurring on the output shaft. However, the governor pressure is transmitted to the valve, and there is some trouble in the hydraulic circuit until the shift actuator is actuated, causing the phenomenon that the start of shift control is delayed while the governor pressure has reached the value at the time of shifting. However, the above technique cannot measure this delay. This is the same in the case of the technique A.

The technique disclosed in Japanese Patent Application Laid-Open No. 63-168531 only discloses that the governor pressure can be varied in accordance with the actual vehicle acceleration state. I do not know whether to measure. Finally, the technique disclosed in Japanese Patent Application Laid-Open No. 62-106340 is
This technique measures the shift engagement time when the vehicle is switched to the “R” or “D” range while the vehicle is stopped in the “P” or “N” range. The shift engagement time that occurs during the D range cannot be measured. SUMMARY OF THE INVENTION The present invention solves the above-mentioned drawbacks, and makes it possible to accurately measure a time difference generated during acceleration from a shift start timing to a shift completion timing.

[0008]

According to the present invention, there is provided:
A device that transmits the torque that reproduces the actual vehicle acceleration time to the input shaft of the hydraulic automatic transmission, and measures the shift engagement time while applying a load that reproduces the actual vehicle acceleration time to the output shaft. A hydraulic circuit, comprising: means for detecting the timing at which the torque pulsates; means for detecting the timing at which the torque transmitted to the output shaft changes suddenly; and means for calculating the time difference between the two detected timings. We have created a shift engagement time measuring device for automatic transmissions.

[0009]

The governor pressure pulsates at the shift start timing. In the present invention, the shift start timing is detected by detecting the timing at which the pulsation occurs. Also, at the shift completion timing, the torque of the output shaft suddenly changes from a large value at the low speed stage to a low value at the high speed stage.
In the present invention, the shift completion timing is detected by detecting the sudden change timing. As a result, according to the present invention, the time difference from the shift start timing to the shift completion timing can be accurately measured.

[0010]

Next, an embodiment of the present invention will be described. FIG. 1 shows the overall configuration of this embodiment. An input shaft drive motor 24 is connected to an input shaft 25 of a hydraulic automatic transmission 20 via a torque sensor 22. The output shaft 23 has a torque sensor 18 and a gear train 14 → 10 → 8 →
The output shaft load motor 4 for applying a load to the output shaft is connected via 6, 16, 12 → 8 → 6. Each motor 4, 2
4 are connected to pulse generators 2 and 26 that output pulses each time the motor rotates by a unit angle. The gear trains 14 → 10 → 8 and 16 → 12 → 8 limit the differential of the output shaft 23. Also, the governor pressure sensor 28 is connected to the automatic transmission 20.
Is connected.

The pulse waves of the pulse generators 2 and 26 are input to the CPU 32 via the I / O 30. CPU3
2 operates according to a program stored in the ROM 34, calculates the number of pulses input per unit time, calculates the respective rotation speeds of the input shaft 25 and the output shaft 23, and outputs the calculated rotation speed as I It is sent to another CPU 40 via / O36.

The other CPU 40 receives detection signals from the torque sensors 18 and 22 and the governor pressure sensor 28 via an I / O 38. The CPU 40 is a ROM 42
The input signal is processed according to the program stored in the I / O 44 and a control signal based on the processing result is sent to the output shaft load motor 4 and the input shaft drive motor 24 via the I / O 44. In addition, the console 46 is controlled.

FIG. 2 shows a processing procedure for reproducing the actual vehicle acceleration state in the automatic transmission for measurement. First, the motors 4 and 24 are controlled in step S2. In this embodiment, since the test is performed in a state where the engine output is increased and the vehicle speed is accelerated, the output of the motor 24 is increased after the start of the measurement, and the rotation speed of the motor 4 is accelerated. , The motors 4 and 24 are controlled. Thereby, the automatic transmission 20 is reproduced in a state where the vehicle is actually accelerated.

In step S4, the governor pressure detected by the governor pressure sensor 28 after the start of measurement is stored and stored in the RAM 42 one after another. Similarly, in step S6, the torque values detected by the torque sensor 18 and transmitted to the output shaft 23 are stored and stored one after another. The governor pressure and the output shaft torque are sampled at intervals of ΔT. The above processing is continued until the switching from the first speed to the second speed,... → the highest speed is completed (step S8).

According to the above processing, for example, the governor pressure P and the output shaft torque T illustrated in FIG. 3 are obtained. This corresponds to the shift from the first speed to the second speed, but a similar change occurs at other shifts.

The governor pressure P increases as the vehicle speed increases. When a predetermined vehicle speed is reached, a shift valve for shifting is operated. At this time, the governor pressure pulsates. PV in the figure corresponds to this pulsation. When the shift valve for shifting is actuated, the actuator for shifting (piston in this embodiment)
Starts operating, and when the actuator has finished operating, the gear change is completed, and the output shaft torque T rapidly decreases as indicated by TD.

When the measurement process of FIG. 2 is completed (step S
8 is yes), as shown in step S10,
The analysis processing routine is started. Details of the analysis processing routine are shown in FIG. 3 and 4, N
Corresponds to the sampling numbers accumulated and stored in steps S4 and S6 in FIG. First, in step S12 in FIG. 4, a sampling number N0 immediately after the start of measurement is set in N. Next, in step S14, the absolute value of the difference between the output shaft torque T sampled between the sampling numbers N-ΔN and N and the average value of the output shaft torque T sampled between the sampling numbers N and N + ΔN ( The value on the left side of step S14) is compared with a predetermined value ΔTR or more. Here, a short time is set as ΔN as shown in FIG.

As shown by N0 or N1 in FIG. 3, when the output shaft torque T fluctuates continuously, the absolute value of the difference does not exceed the predetermined value ΔTR. Predetermined value ΔTR
Is set to a higher value. If the absolute value of the difference is not equal to or larger than the predetermined value ΔTR, 1 is added to N in step S16 in FIG. 4, and the comparison in step S14 is continued. In the case of FIG. 3, N starts to increase from N0 and repeats the processing of steps S14 and S16 until immediately before N2.
Although the output shaft torque T changes slightly during the shifting as shown by TV, step S14 does not become YES at TV because ΔTR is set to be greater than or equal to this value. Step S is performed while N is increased in this manner.
When the comparison of 14 is repeated and N = N2 is reached, the output shaft torque T changes abruptly, so that step S14 becomes YES. Therefore, in step S18, N
Is stored as N2. As can be seen from the above, the loop of steps S14 and S16 and the step S18 exiting from it perform the processing for detecting the timing at which the output shaft torque T shown by TD in FIG. 3 changes suddenly.

When N2 is specified in this way, step S20 is executed next. This is for comparing whether or not the average value of the governor pressure P changes by a predetermined value ΔP or more, and corresponds to step S14. As shown in FIG. 3, when N = N2, the governor pressure is continuously changing, and the result in step S20 is NO. Therefore, this time, 1 is subtracted from N (step S22), and step S20 is executed for this new N. That is, a search is made for the timing at which the governor pressure P changes abruptly while going back in the past. In FIG. 3, when N advances to N3 (returns to the past), step S20 becomes YES. Therefore, in step S24, the sampling number N at that time is stored as N3.

By the above processing, the sampling number at the timing when the output shaft torque T suddenly changes is set to N2.
3 stores the sampling number at the timing when the governor pressure P suddenly changes. Step S26,
The difference between this sampling number and the sampling period Δ
A process of multiplying T and converting the time difference is executed. As a result, the time from the shift start timing to the shift completion timing, that is, the shift engagement time (TIME) is calculated.

The shift engagement time (TIME) thus calculated is displayed on the console 46 (step S).
28) The operator is notified. Step S3
0, the shortest time TIME1 of the normal product and the longest time TIME
2, and if there is between the two, OK (S32) is displayed, otherwise NG (S34) is displayed.

In this embodiment, the governor pressure pulsation timing detecting means of the present invention comprises the governor pressure sensor 28 and the I / O 38.
And a loop for repeating steps S20 and S22 in FIG. 4 and exiting from the loop to execute the processing of step S24.
It is composed of PU40. Means for detecting a sudden change timing of the output shaft torque includes a torque sensor 18, an I / O
38 and steps S14 and S16 of FIG.
Then, the CP that escapes and executes the process of step S18
U40. Further, in the present embodiment, the means for calculating the time difference between the two timings corresponds to step S
26 and a CPU 40 for executing the same.

In the present embodiment, while the acceleration state is reproduced in the transmission, the governor pressure and the output shaft torque are temporarily stored and the sampling values are analyzed later. The pulsation timing or the sudden torque change timing may be detected. Furthermore, in the present embodiment, the state in which the engine output is accelerated while being increased is reproduced. However, the state in which the engine is accelerated while the engine output is kept constant may be reproduced. The shift engagement time may be measured under various acceleration conditions. In addition, in this embodiment, since the time is measured from the governor pressure pulsation timing, if there is an abnormality in the hydraulic circuit of the governor pressure → the valve → the shift actuator, the abnormality can also be detected, which is well-suited to the inspection purpose of the hydraulic automatic transmission. You can measure the time to do.

[0024]

According to the present invention, the shift engagement time is measured based on the governor pressure pulsation timing generated at the shift start timing and the sudden change timing of the output shaft torque generated at the shift completion timing. The shift engagement time can be measured.

[Brief description of the drawings]

FIG. 1 is a system diagram according to an embodiment embodying the present invention;

FIG. 2 is a processing procedure diagram during measurement.

FIG. 3 is a diagram showing measured data;

FIG. 4 is a diagram showing an analysis processing procedure executed after measurement.

[Explanation of symbols]

4: output shaft load motor 20: hydraulic automatic transmission 23: output shaft 24: input shaft drive motor 25: input shaft 28: governor pressure sensor 38: I / O, 40: CPU, steps S20, S2
2, S24 → governor pressure pulsation timing detecting means 38: I / O, 40: CPU, steps S14, S1
6, S18 → output shaft torque sudden change timing detecting means 40: CPU, step S26 → time difference calculating means

Claims (1)

(57) [Claims] An apparatus for measuring a shift engagement time in a state in which a torque that reproduces actual vehicle acceleration is transmitted to an input shaft of a hydraulic automatic transmission and a load that reproduces actual vehicle acceleration is applied to an output shaft of the hydraulic automatic transmission. And a means for detecting a timing at which the governor pressure pulsates; a means for detecting a timing at which the torque transmitted to the output shaft changes suddenly; and a means for calculating a time difference between the two detected timings. A shift engagement time measuring device for a hydraulic automatic transmission, characterized in that: