JPH0314961A - Torque detection device of transmission - Google Patents

Abstract

PURPOSE:To accurately detect driving torque irrespective of aging deterioration or the like in the driving shaft by zero(0)-compensating the driving torque value calculated under operation where no deriving force is not acted on the driving shaft when the driving torque is calculated by the torsional rigidity of the driving shaft. CONSTITUTION:A torque detecting device comprises two sets of rotation signal detection means 30, 31 to detect the rotation signal of driving shaft at different two positions of driving shaft of transmission, torque calculation means 35 to calculate the drive torque of the transmission based on the phase difference between rotational signals detected by these means 30, 31. This device is also provided with an operation condition detection means 36 to detect the operation condition where no driving force is applied to the driving shaft of transmission, a correction means 37 to correct the drive torque of the torque calculation mean 35 zero(0) so as to make zero the driving torque value to be calculated based on the phase difference between the rotation signals of the means 30, 31 in the operation conditions detected by an operation condition detection means 36.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an improvement in a torque detection device for a transmission, which detects torque acting on a drive shaft of the transmission.

(Prior Art) Conventionally, for example, in an automatic transmission, when the engagement force of various friction elements is insufficient, the friction elements slip and drive torque cannot be transmitted well, whereas when the engagement force of the friction elements is high, However, there are disadvantages such as shift shock.

For this reason, in order to control the line pressure that engages the friction elements to a value that corresponds to the drive torque of the transmission, instead of the conventional structure that indirectly detects the drive torque using the throttle valve opening, for example, As disclosed in Japanese Unexamined Patent Publication No. 62-224765, it is known to employ a configuration in which a torque sensor is used to directly detect driving torque.

(Problems to be Solved by the Invention) Therefore, for example, for detecting the drive torque of a transmission, it is conceivable to use a torque sensor that utilizes the torsional rigidity of the drive shaft. In other words, the configuration of this sensor is such that two sets of rotation sensors using an electromagnetic pickup type or a phototransistor are placed, for example, at the front and rear of the drive shaft of the transmission, and drive torque acts on the drive shaft of the transmission. When the motor is running, it utilizes the characteristic that a phase difference occurs between the detected rotation signals due to torsional changes in the drive shaft, and directly calculates and detects the drive torque according to the magnitude of this phase difference. Structured.

However, when using the above torque sensor,
Due to age-related deterioration of the drive shaft, different phase differences occur even when the same drive torque is applied, resulting in detection of different torque values, resulting in disadvantages such as the inability to accurately control the line pressure.

The present invention has been made in view of the above, and its purpose is to accurately measure the drive torque regardless of age-related deterioration of the drive shaft when using a torque sensor that utilizes the torsional rigidity of the drive shaft of a transmission. The purpose is to detect.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a method for calculating the drive torque even if the phase difference occurring between the two rotation signals changes due to age-related deterioration of the drive shaft. The zero point of is to be corrected correctly.

In other words, the specific solution of the present invention, as shown in FIG.
1 and a torque calculation means 35 for calculating the drive torque of the transmission based on the phase difference between the rotation signals detected by the two sets of rotation signal detection means 30 and 31. Assuming that. and an operating state detecting means 36 for detecting an operating state in which no driving force is applied to the drive shaft of the transmission; and when the operating state detected by the operating state detecting means 36, the two sets of rotation signal detecting means 30. 31
A correction means 37 is provided for correcting the zero point of the drive torque of the torque calculation means 35 so that the drive torque value calculated based on the phase difference between the rotation signals of is set to zero.

(Function) With the above configuration, in the present invention, the phase difference that occurs between the two rotation signals to be detected differs depending on the aging of the drive shaft even when the same value of drive torque is applied. Since the zero point is corrected so that the drive torque value calculated in an operating state where no force is applied is zero, the drive torque of the transmission can be calculated with high accuracy regardless of age-related deterioration of the drive shaft.

(Effects of the Invention) As explained above, according to the torque detection device for the transmission of the present invention, when calculating the drive torque using the torsional rigidity of the drive shaft, the driving force is not applied to the drive shaft. Since the zero point correction has been made so that the drive torque value calculated in is zero, it is possible to calculate the drive torque with a simple configuration and increase the accuracy of the calculated drive torque value, regardless of age-related deterioration of the drive shaft. Can be maintained.

(Example) Hereinafter, an example of the present invention will be described based on the drawings from FIG. 2 onwards.

FIG. 2 shows an automatic transmission with 4 forward speeds and 1 reverse speed, where 1 is an engine output shaft, 2 is a bomb 2a connected to the engine output shaft 1, a stator 2b, and a transmission bin 2c. The stator 2b is fixed to the case 4 via a one-way clutch 3 for preventing the stator 2b from rotating in the opposite direction to the turbine 2c. Turbine 2 of the torque converter 2
A turbine shaft 2d serving as a drive shaft is connected to C, and a speed change gear device is connected to the turbine shaft 2d.

The speed change gear device 5 is equipped with a Ravigneau type planetary gear mechanism 7 inside, and the planetary gear mechanism 7 includes a small-diameter sangya 8 and a large-diameter sangya 9 arranged in the front and rear, and the small-diameter sangya 8.
A short pinion gear 10 meshes with the large diameter sun gear 9 and the short pinion gear 10, a long pinion gear 11 meshes with the long pinion gear 11, and a ring gear 12 meshes with the long pinion gear 11. Above small path Sangya 8
is connected to the forward clutch 15 disposed behind it and the turbine shaft 2 connected in series to the clutch 15.
a first one-way clutch 16 that prevents reverse drive of d; and a coast clutch 17 connected in parallel with these clutches.
It is connected to the output shaft 2d of the torque converter 2 via. In addition, the large-diameter Sangya 9 also includes a 2-4 brake 18 and a 2-4 brake 18 arranged diagonally rearward thereof.
The torque converter 2 is connected to the output shaft 2d of the torque converter 2 via a reverse clutch 19 arranged at the rear of the torque converter 2. Furthermore, the long pinion gear 11 (hereinafter referred to as a low & reverse brake 21 that fixes the long pinion gear 11 via its rear side carrier 20) and a low and reverse brake 21 that fixes the long pinion gear 11 through its rear side carrier 20, and a 2nd to allow rotation
A one-way clutch 22 is connected in parallel, and its front side is connected to the output shaft 2d of the torque converter 2 via a 3-4 clutch 24.

In addition, the ring gear 12 is connected to an output gear 25 located in front of it. In the figure, 27 is a lock-up clutch that directly connects the engine output shaft 1 and the turbine shaft 2d, and 28 is an oil pump driven by the engine output shaft 1 via an intermediate shaft 29.

Therefore, the turbine shaft 2d as a drive shaft of the transmission
, first and second rotation sensors are provided as rotation signal detection means for detecting rotation signals of the turbine shaft 2d at a portion slightly forward of the center portion and at a rear end portion where the reverse clutch 19 is disposed. The rotation sensors 30 and 31 in which the rotation sensors 30 and 31 are arranged are of an electromagnetic pickup type, and include a rotating disk 30a that rotates integrally with the turbine shaft 2d (the second rotation sensor 31 is not shown).
The rotating disk 30a has a plurality of convex portions arranged at equal intervals on the outer periphery, and an induced electromotive force is generated according to the rotation of each of the convex portions. sensor 30,
The rotation signal detected by 31 is input to a controller 32 which has a CPU etc. inside.

The controller 32 has a function of controlling a plurality of electromagnetic valves SQL provided in a hydraulic circuit 38 for controlling engagement and disengagement of friction elements such as the clutch of the automatic transmission, and also detects the temperature of lubricating oil of the engine. Oil temperature sensor 3
3 and each automatic transmission? Range position, e.g. P (parking)
Detection signals for an inhibitor switch 34 that detects the position, N (neutral) position, and D (driving) position, and an idle switch 35 that detects the idle operating state of the engine are manually generated.

Next, control of the line pressure by the controller 32 will be explained based on the control flow shown in FIG. 3.

After starting, initial settings were made in step S1 (setting r1'-0 for the average value of the delay time and setting n-0 for the number of measurements n, which will be described later), and then placing it on the front side of the turbine shaft in step S2. FIG. 4 (a) of the first rotation sensor 30
) is detected at the rising edge of the pulse t■, and at the same time, the second
The pulse rising time t1 of the rotation signal of the rotation sensor 31 shown in FIG. 3B is detected. Then, in step S4, calculate the time difference tn between the detected time t■ and the time t1,
In order to absorb the engine torque, the above operation is repeated n times in step S5.

Thereafter, in step S6, the average delay time ゜口゜ for n times is calculated, and in step S7, the driving torque T acting on the turbine shaft is approximately calculated based on the following formula: Then, this determined driving torque T is stored in the memory in step S8.

Thereafter, from step S9 onwards, the zero point correction of the calculation formula for the drive torque T is performed. That is, in step S9, it is first determined whether the conditions for zero point correction are satisfied. This determination is made when the temperature of the engine lubricating oil is equal to or higher than the set temperature value corresponding to when the engine is warm, and when the range position of the automatic transmission is P.
Alternatively, when the engine is in the N range position and the engine is in an idling operating state, the zero point correction condition is satisfied.

Then, when this condition is established, after changing the value of the driving torque T stored in the memory in step Slfi to T-0,
In step Sl+, the formula for calculating the driving torque T is calculated as shown by the broken line in FIG.
The constant b is replaced with b+α so that l+b=0, so that the zero point of the calculation formula is corrected, and the process returns to step S1.

Moreover, FIG. 6 shows line pressure control of an automatic transmission, and after reading the driving torque T from the memory in step SA+, the above-mentioned reading is performed in step SA2 based on the measured torque-duty ratio characteristics shown in FIG. The duty rate corresponding to the drive torque T is calculated, and the solenoid valve is duty-controlled at the calculated duty rate in step SA2.
Returning to step SAI is repeated.

Therefore, in steps Sl to S7 of the control flow shown in FIG. 3, the drive torque T of the transmission is calculated based on the delay time tn (phase difference) between the rotation signals detected by the two sets of rotation sensors 30 and 31. The torque calculation means 35 is configured to do the following. Further, in step S9, an operating state detecting means 36 is configured to detect an operating state in which no driving force is applied to the turbine shaft 2d of the transmission, and in step Sl+, the operating state detected by the operating state detecting means 36 is configured. In this case, the zero point of the drive torque calculation formula in the torque calculation means 35 is set so that the value of the drive torque T calculated based on the phase difference tn between the rotation signals of the two sets of rotation sensors 30 and 31 becomes a zero value. A correction means 37 is configured to correct by rewriting the constant b.

Therefore, in the above embodiment, when the turbine shaft 2d deteriorates over time, the phase difference tn between the rotation signals of the two sets of rotation sensors 30 and 31 increases, but the drive torque T
The constant b in the calculation formula is rewritten, and in an operating state where no driving force is applied to the turbine shaft 2d, the zero point is corrected so that the drive torque T calculated by the above calculation formula becomes a zero value. The value of the driving torque T has good accuracy regardless of age-related deterioration of the turbine shaft 2d. As a result, the torque sensor can be easily configured with two sets of rotation sensors 30 and 31, and the line pressure of the automatic transmission can be adjusted with high precision, without causing slippage of friction elements or shift shock during gear shifts. Automatic gear shifting can be performed well.

Incidentally, in the above embodiment, a case where the present invention is applied to an automatic transmission has been described, but it goes without saying that the present invention can be similarly applied to a manual transmission.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of the present invention. 2 to 7 show embodiments of the present invention, FIG. 2 is a skeleton diagram of an automatic transmission, FIG. 3 is a flowchart for calculating the driving torque, and FIG. 4 is a diagram showing the relationship between two sets of rotation signals. FIG. 5 is a diagram showing the phase difference, FIG. 5 is an explanatory diagram of zero point correction, FIG. 6 is a flowchart diagram showing line pressure control, and FIG. 7 is a diagram showing measured torque-duty rate characteristics. 30.31... Rotation sensor (rotation signal detection means), 3
2... Controller, 34... Inhibitor switch, 35... Torque calculation means, 36... Operating state detection means, 37... Correction means. 2 others Fig. 4 T Chiewa Enoki v T Fig. 5

Claims (1)

[Claims] (1) Two sets of rotation signal detection means for detecting rotation signals of the drive shaft at two different locations on the drive shaft in the transmission;
and a torque calculation means for calculating the drive torque of the transmission based on the phase difference between the rotation signals detected by the rotation signal detection means of the set, and an operating state in which no driving force acts on the drive shaft of the transmission. and a driving torque value calculated based on the phase difference between the rotation signals of the two sets of rotation signal detection means to a zero value when the operation state detected by the operation state detection means is detected. A torque detection device for a transmission, comprising: a correction means for correcting the zero point of the driving torque of the torque calculation means.