JPS63262535A - Torque detector for automobile - Google Patents

Abstract

PURPOSE:To accurately measure a torque, by setting the average value of the outputs of a torque sensor during a predetermined period to a zero point before calculating the torque. CONSTITUTION:An automobile does not yet run within the predetermined period immediately after the operation of an ignition switch is started and no torque acts on a torque transmission shaft. The average value of the outputs of a torque sensor 18 during this period is calculated by an averaging processing means 20 and regarded as the zero point of the torque sensor 18. The deviation between said average value and the output value of the torque sensor 18 is calculated by a calculation means 21 to be outputted as a torque value.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a torque detection device for an automobile, and more particularly to one that accurately measures the transmitted torque of a torque transmission shaft.

(Prior art) Conventionally, as a four-wheel drive vehicle, for example, Japanese Patent Laid-Open No. 61-111
- As disclosed in Japanese Patent No. 155027, the output torque of the transmission is distributed between the front wheels and the rear wheels at an appropriate ratio depending on the driving condition, and each output torque is transmitted through two propeller shafts. It is known that the power is transmitted to the front wheels and the rear wheels, respectively. In this case, a torque sensor is provided on the output shaft of the transmission to detect the torque acting on the output shaft, and the output distribution to the front wheels and rear wheels is controlled based on the measured value of this torque sensor. There is. A commonly used torque sensor is one in which, for example, a strain gauge is attached to an output shaft and the torque is measured based on the output voltage of the strain gauge.

(Problem to be Solved by the Invention) However, in the above-mentioned conventional system, the torque is only measured indirectly by the state quantity such as the strain of the output shaft, so the torque is not affected by changes in temperature etc. There is a problem that a deviation occurs between the measured value and the true torque value, making it impossible to accurately control the output distribution.

The present invention has been made in view of the above, and its purpose is to adjust the zero point of a torque sensor using the output of the torque sensor when no torque is acting on a torque transmission shaft such as a transmission output shaft. The purpose of this is to make it possible to accurately measure torque without being affected by temperature changes, etc.

(Means for Solving the Problems) In order to achieve the above object, in the present invention, the average value of the torque sensor output when the car is not running is set as the zero point of the torque sensor, and the torque value is measured using this as a reference. It is to do so.

Specifically, the solution taken by the present invention, as shown in FIG. an average processing means 2o that calculates and stores an average value of the output of the torque sensor 18 in The configuration includes a calculation means 21 for calculating .

(Function) With the above configuration, in the present invention, the vehicle is not yet running and no torque is acting on the torque transmission shaft within the predetermined period immediately after the ignition switch starts operating, so the torque sensor 18 during this period The average value of the output can be regarded as the zero point of the torque sensor 18. By calculating the difference between this average value and the output value of the torque sensor 18 as a torque value, measurement errors due to the influence of temperature changes etc. are removed from the output of the torque sensor 18, and torque can be accurately measured. Become.

(Example) Embodiments of the present invention will be described below based on the drawings.

2 and 3 show a four-wheel drive vehicle equipped with a torque detection device according to an embodiment of the present invention. In the figure, 1 is an engine, 2 is a transmission, and 3 is a transfer. A drive shaft 4 is pivotally supported on the transfer 3, and one end of the drive shaft 4 is connected to an output shaft 2a of the transmission 2.

Furthermore, a wet friction clutch 5 for the front wheels and a wet friction clutch 6 for the rear wheels are attached to the drive shaft 4. The output shaft of each clutch 5, 6 is two propeller shafts 7.
The engine 1 is connected to a front wheel 9 and a rear wheel 10 via a transmission 8, and after the output torque of the engine 1 is shifted by the transmission 2, it is distributed to the front wheel side and the rear wheel side at a predetermined ratio by a transfer 3. The distributed torque is transmitted via the propeller shaft 7.8 to the front wheels 9 and the rear wheels 10, respectively.

The hydraulic working chamber of each of the clutches 5 and 6 is a hydraulic pressure supply passage 11.
．． 12 to a hydraulic pump 13, respectively. Each hydraulic supply passage 11.12 has a respective clutch 5.
By adjusting the hydraulic pressure supplied to the hydraulic working chamber of 6, each clutch 5
, 6 variable flow control valve 14.1 for changing the transmitted torque
5 are provided respectively.

= 5 - Also, 16 is an ignition sensor that detects whether the ignition switch is ON or OFF, 17 is a neutral sensor that detects whether the transmission 2 is in the neutral position, and 18 is the output of the transmission 2. The output shaft 2 is provided on the shaft 2a.
The output signal of each of the sensors 16 to 18 is input to a controller 19, and the controller 19 controls the operation of each of the variable flow control valves 14 and 15. is controlled.

As shown in FIG. 4, the torque sensor 18 includes a strain gauge 1.88 attached to the surface of the output shaft 2a of the transmission 2, and a strain gauge 1.88 attached to the flange formed on the output shaft 2a. The output voltage signal is
a transmitter 18b that converts into an M wave and transmits it; the strain gauge 18a and the transmitter 18 provided on the flange;
), and a ring-shaped receiving section 18d that is disposed in a stationary state facing the flange section and receives the signal transmitted from the transmitting section 18b using the flange section as an antenna, and outputs The amount of shear strain on the shaft 2a is detected as a physical quantity related to i~lux, and the torque is measured based on this shear strain.

Next, the operation control of the controller will be explained based on the flowchart of FIG. 5. First, in step 81, a signal from the ignition sensor 16 is read, and in step S2, it is determined whether the ignition switch has been switched from OFF operation to ON operation. If this determination is No, it is determined that the car is running, and the process immediately proceeds to step $9 without performing zero point adjustment. On the other hand, if YES, the signal of the neutral sensor 17 is read in step S3, and the signal of the neutral sensor 17 is read in step S4.
It is determined whether transmission 2 is in neutral or not. If this determination is NO, it is determined that torque is acting on the transmission output shaft 2a, and the process immediately proceeds to step S without performing zero point adjustment. On the other hand, Y
At FS, it is determined that the car is not running yet, and in step S5 the signal from the torque sensor 18 is changed, for example, at 2/sec.
Read with 0 reading speed.

Then, in step S6, it is determined whether or not the number of data to be read has reached a predetermined number. If the number of read data is less than the predetermined number (No), the process proceeds to step $9 to continue reading the signal of the torque sensor 18. On the other hand, when the number of read data reaches a predetermined number (YES), the average value of the torque data is calculated in step S7, and this average value is recorded in the RAM as the zero point of the torque sensor 18 in step S8.

Thereafter, in step $9, the signal from the torque sensor 18 is read, the deviation between the average value and the output value of this torque sensor is calculated, and the torque value is calculated based on this deviation.

In the above flow, steps 81 to S8 constitute the averaging processing means 20 that calculates and stores the average value of the output of the torque sensor 18 within a predetermined period from the start of operation of the ignition switch, and
9 and S10 constitute calculation means 21 which calculates a torque value based on the deviation between the average value stored in the average processing means 20 and the output value of the torque sensor 18.

Therefore, in the above embodiment, it can be assumed that the vehicle is not yet running and no torque is acting on the transmission output shaft 2a. The torque sensor output is read within a predetermined period immediately after the ignition switch starts operating, and the average value of this torque data is set as the zero point, and the deviation from the torque sensor output value is calculated, making it easy to adjust the zero point of the torque sensor. By this zero point adjustment, it is possible to accurately measure torque by eliminating measurement errors caused by the influence of temperature, etc., on the output force of the torque sensor.

(Effects of the Invention) As explained above, according to the i-luke detection device for an automobile of the present invention, the average value of the torque sensor output within a predetermined period from the start of operation of the ignition switch is set as the zero point, and this average value Since the torque is calculated based on the deviation between the torque sensor output value and the torque sensor output value, the zero point adjustment of the 1-lux sensor can be easily performed and the torque can be accurately measured.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of the present invention. 2 to 5 show embodiments of the present invention, FIG. 2 is a plan view of the main parts of the automobile, FIG. 3 is a schematic configuration diagram of the torque transmission system,
FIG. 4 is a partially enlarged perspective view of the circumferential surface of the torque sensor on the transmission output shaft, and FIG. 5 is a flowchart illustrating the operation of the controller. 2... Transmission, 2a... Output shaft, 16
... Ignition sensor, 18 ... Torque sensor, 20 ... Average processing means, 21 ... Calculation means.

Claims (1)

[Claims] (1) A torque sensor that detects a signal related to torque on the torque transmission shaft of an automobile, and an averaging processing means that calculates and stores the average value of the output of the torque sensor within a predetermined period from the start of operation of the ignition switch. 1. A torque detection device for an automobile, comprising: a torque detection device for calculating a torque value based on a deviation between the average value stored in the average processing device and the output value of the torque sensor.