JPS6150250B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a chassis dynamometer that is particularly suitable for performing acceleration tests on automobiles and the like.

[Conventional technology]

Fig. 2 shows the configuration of a general chassis dynamometer, where 1 is a vehicle under test such as a car, 2 is a rotating drum on which the tires of the vehicle under test 1 are placed, and this rotating drum 2 is a frame 4. is rotatably supported via a drum shaft 3. Reference numeral 5 denotes a plurality of flywheels having an inertia amount corresponding to the weight of the test vehicle 1 attached to the test vehicle 1 and having several types of inertia amounts, and these flywheels 5 are connected to the drum shaft 3. It is detachably supported by the flywheel shaft 6. A dynamometer 7 absorbs the power of the vehicle under test 1 and the rotating shaft system, and this dynamometer 7 is connected to the flywheel shaft 6. 8 is dynamometer 7
This figure shows a speed detector that detects the speed of the rotating shaft system transmitted to the rotary shaft system. As a patent related to this type of chassis dynamometer, for example, Japanese Patent Application Laid-Open No. 51-53301 is known.

Figure 3 shows the running resistance and mechanical loss curve of the test vehicle 1, where the vertical axis shows the running resistance and mechanical loss, the horizontal axis shows the running speed, and curve a shows the running resistance and mechanical loss curve of the test vehicle 1. 1, curve b shows the mechanical loss curve of the test vehicle (chassis dynamometer), and curve c shows the running resistance curve of test vehicle 1 after removing the mechanical loss. Further, the curves a, b, and c change depending on the combination of the vehicle under test 1 and the flywheel 5.

FIG. 4 is a block diagram showing a control device that imparts running resistance characteristics to the test vehicle 1, and 9 is a running resistance that electrically converts the running resistance curve a shown in FIG. 3 and outputs a running resistance signal. 10 is a mechanical loss amount setting device that electrically converts the mechanical loss curve b shown in FIG. 3 and outputs a mechanical loss signal; 11 is a subtracter into which the running resistance signal and the mechanical loss signal are input. The subtracter 11 outputs a value obtained by subtracting the mechanical loss signal from the running resistance signal, that is, a running resistance signal obtained by electrically converting the running resistance curve c shown in FIG. 2, and supplies it to the dynamometer 7. do. Reference numeral 12 denotes an operational amplifier that compares the running resistance signal output from the subtracter 11 with the detection signal output from the speed detector 8 and performs arithmetic processing.

Next, a control method for imparting running resistance characteristics to the vehicle under test 1 will be explained with reference to the block diagram of FIG.

The flywheel axis 6 is a flywheel axis 6 in which an amount of inertia corresponding to the weight of the vehicle under test 1 is calculated in advance, and a flywheel that approximates this amount of inertia is selected from among a plurality of flywheels 5 having several types of amounts of inertia.
Attach to. Mechanical losses such as windage resistance and rolling resistance were actually measured while rotating the rotating system with the flywheel 5 selected as described above attached to the flywheel shaft 6, and a mechanical loss curve b was obtained from the mechanical losses. and the running resistance curve a are electrically converted by a mechanical loss amount setting device 10 and a running resistance setting device 9, respectively, and outputted as a mechanical loss signal and a running resistance signal, and these signals are input to a subtracter 11. This subtracter 11 supplies the dynamometer 7 with a value obtained by subtracting the two signals, that is, a signal corresponding to the running resistance excluding the amount of mechanical loss in the rotating shaft system. Therefore, the dynamometer 7 is activated by the signal output from the subtracter 11, and applies a load to the vehicle under test 1 corresponding to the running resistance curve c shown in FIG.

Also, the signal supplied to the dynamometer 7 is the speed detector 8
Feedback control is performed via a feedback amplifier (not shown) using a detection signal from a load detector (not shown) that detects the load of the dynamometer 7.

[Problem that the invention seeks to solve]

However, in the above control method, the test vehicle 1
Flywheel 5 equivalent to the amount of inertia according to the weight of
When selecting, since the number of flywheels 5 is limited, even if a plurality of flywheels 5 are selected and combined, it is impossible to make the above inertia equivalent. A flywheel 5 was selected that approximated the amount. That is,
For example, if the weight of the test vehicle 1 is 2500Kg, even if multiple flywheels 5 are selected and combined, the weight will be 2450Kg.
Or 2550Kg, so these flywheels 5 were approximated to 2500Kg. Since a flywheel approximated to the amount of inertia was used in this way, it was not possible to provide the test vehicle 1 with accurate running resistance characteristics.

In addition, conventionally, the mechanical loss curve b obtained through actual measurements is set while being appropriately adjusted using a manual mechanical loss amount setting device 10, for example, a potentiometer. This method has drawbacks such as being time consuming.

In view of the above points, it is an object of the present invention to provide a chassis dynamometer that can impart accurate running resistance characteristics to a test vehicle in a short period of time.

[Means for solving problems]

In order to achieve the above objective, a weight setting device is used to set the weight of the test vehicle, and an inertia amount corresponding to the weight of the test vehicle and an inertia amount approximating this inertia amount are calculated based on multiple flywheels. and an arithmetic unit that calculates a deviation inertia amount from both of the inertia amounts, an acceleration detector that detects the acceleration of the flywheel, a running resistance setting device that outputs a running resistance signal of the test vehicle, and the approximated inertia. a mechanical loss amount setting device that sets the mechanical loss amount according to the amount of deviation; a differential amplifier that calculates the deviation inertia amount and the acceleration value of the flywheel and outputs a signal corresponding to the deviation inertia amount; and the running resistance setting device. A subtracter subtracts the output signal of the mechanical loss setting device from the output signal of the device, and the approximate running resistance value from the subtractor and the deviation inertia from the differential amplifier are used to calculate the value according to the weight of the test vehicle. The control device consists of a comparator and a comparator that calculates the amount of inertia and outputs it to the dynamometer.

[Effect]

In addition to calculating the amount of inertia according to the weight of the test vehicle, the amount of inertia that approximates this amount of inertia is calculated from among multiple flywheels, and the deviation amount of inertia obtained from these two amounts of inertia and the acceleration value is calculated. Calculates using a differential amplifier. In addition, the amount of mechanical loss corresponding to the approximated amount of inertia is calculated, this calculated value and the running resistance value from the running resistor are subtracted using a subtracter, and the approximated running resistance value from this subtracter and the above-mentioned Based on the amount of deviation inertia from the differential amplifier, a signal corresponding to the amount of inertia corresponding to the weight of the vehicle under test is calculated by a comparator and supplied to the dynamometer. As a result, accurate running resistance characteristics can be imparted to the vehicle under test in a short period of time, making it possible to perform acceleration tests on the vehicle under test with high precision.

〔Example〕

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

FIG. 1 is a block diagram showing a control device for a chassis dynamometer according to the present invention, and the same reference numerals as in FIG. 4 indicate the same parts.

Reference numeral 13 denotes a control device that imparts running resistance characteristics including acceleration resistance to the test vehicle 1, and this control device 13 is configured as follows. 14 is a weight setting device for setting the weight of the test vehicle 1; 15 is a computing device for calculating the amount of inertia; this computing device 15 is similar to the weight setting device 1;
The inertia amount corresponding to the weight of the test vehicle 1 input from 4 and the inertia amount approximated to this inertia amount are extracted from the inertia amounts of a plurality of flywheels stored in advance, and both of these inertia amounts are calculated. After calculating the deviation inertia amount (error inertia amount), an electric signal A corresponding to the approximated inertia amount and an electric signal B corresponding to the deviation inertia amount are output. 16 is a mechanical loss amount setting device in which several types of mechanical loss amounts are stored in advance;
This setting device 16 selects and outputs the amount of mechanical loss according to the electrical signal A inputted from the arithmetic unit 15. 17 is an acceleration detector that detects the acceleration of the flywheel 5 applied to the dynamometer 7; 18 is a differential amplifier; A signal C corresponding to the acceleration output from the acceleration detector 17 is calculated to output an electric signal E corresponding to the amount of deviation inertia. The subtracter 11 calculates a running resistance curve C which is a value obtained by subtracting the mechanical loss curve b from the running resistance curve a shown in FIG. 3, and outputs an electric signal D. Reference numeral 19 denotes a comparator for adding and subtracting the electric signals D and E. The comparator 19 corrects the approximated inertia amount to an inertia amount corresponding to the weight of the vehicle under test 1 using the electric signal E from the differential amplifier 18. A signal corresponding to the running resistance is supplied to the dynamometer 7.

Next, a case will be described in which an acceleration test is performed on the vehicle under test 1 using the chassis dynamometer configured as described above.

First, a signal corresponding to the running resistance curve a of the vehicle under test 1 is sent from the running resistance setting device 9 to the weight setting device 14.
The signals corresponding to the weight of the vehicle under test 1 are outputted from the two, and the signal from one running resistance setter 9 is supplied to the subtracter 11, and the signal from the other weight setter 14 is supplied to the calculator 15. be done. Arithmetic unit 1
In step 5, an amount of inertia corresponding to the weight of the test vehicle 1 is calculated, and an inertia amount approximating this amount of inertia is calculated from among a plurality of flywheels 5, and an inertia amount corresponding to the weight of the test vehicle 1 is calculated. The error between the approximate inertial amount and the approximate inertial amount is calculated as the deviation inertial amount. The number of flywheels corresponding to the approximated inertia amount is displayed. A plurality of flywheels 5 corresponding to the approximate inertia amount calculated by the calculator 15
is attached to the flywheel shaft 6. Further, when the electric signal A corresponding to the approximate inertia amount output from the calculator 15 is input to the mechanical loss amount setting device 16,
The mechanical loss amount setter 16 selects a mechanical loss amount corresponding to the approximate inertia amount output from the calculator 15, and a signal corresponding to this mechanical loss amount is supplied to the subtracter 11. The subtracter 11 subtracts the amount of mechanical loss (curve b) from the amount of running resistance (curve a) and outputs the amount of running resistance (curve c). Furthermore, the signal B corresponding to the deviation inertia amount output from the arithmetic unit 15 and the signal C corresponding to the acceleration output from the acceleration detector 17 are input to a differential amplifier 18, and from this differential amplifier 18, the deviation inertia amount is inputted. A corresponding electrical signal E is output. The electrical signal E from the differential amplifier 18 and the electrical signal D from the subtracter 11
is input to the comparison calculator 19. This comparison calculator 19 responds to the weight of the test vehicle 1 by adding the electric signal E (deviation inertia amount) from the differential amplifier 18 and the electric signal D (approximate running resistance value) from the subtractor 11. The amount of inertia is calculated and supplied to the dynamometer 7 as an electrical signal.

〔Effect of the invention〕

According to the chassis dynamometer of the present invention, the inertia of the approximated flywheel is automatically corrected and supplied to the dynamometer, so accurate running resistance characteristics can be imparted to the test vehicle in a short time. This makes it possible to perform acceleration tests on test vehicles such as automobiles with high precision.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing the control device in the chassis dynamometer of the present invention, Fig. 2 is a schematic diagram showing the configuration of the chassis dynamometer, and Fig. 3 shows the running resistance curve, mechanical loss curve, and mechanical loss curve. FIG. 4 is a block diagram showing a control device in a conventional chassis dynamometer. 9... Running resistance setting device, 13... Control device, 1
4... Weight setting device, 15... Arithmetic unit, 16... Mechanical loss amount setting device, 17... Acceleration detector, 18...
...differential amplifier, 19...comparison calculator.

Claims (1)

[Claims] 1. A weight setting device that sets the weight of the tested vehicle, an inertia amount corresponding to the weight of the tested vehicle, and an inertia amount approximating this inertia amount based on a plurality of flywheels, and from both of the above inertia amounts. A computing unit that calculates the deviation inertia amount, an acceleration detector that detects the acceleration of the flywheel, a running resistance setting device that outputs a running resistance signal of the test vehicle, and a mechanical loss amount according to the approximated inertia amount. a mechanical loss amount setter for setting the amount of deviation, a differential amplifier that calculates the deviation inertia amount and the acceleration value of the flywheel and outputs a signal corresponding to the deviation inertia amount, and a mechanical loss amount setting device from the output signal of the running resistance setting device. A subtracter subtracts the output signal of the quantity setting device, and an inertia amount corresponding to the weight of the test vehicle is calculated using the approximate running resistance value from the subtracter and the deviation inertia amount from the differential amplifier. A chassis dynamometer characterized in that a control device includes a comparison calculator that outputs an output to a dynamometer.