JPS6225708Y2 - - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a brake dynamometer.

The basic configuration of a conventional brake dynamometer is
As shown in FIG. 1, the flywheel 2 is accelerated to the braking start speed by the drive motor 1, which is a DC motor, and when the energy stored in the flywheel 2 is consumed by the brake under test 3. The torque applied to the brake 3 is measured by a torque meter 4 connected to its fixed side. Here, since the flywheel 2 is configured so that its moment of inertia can be adjusted according to the type and capacity of the brake 3 to be tested, there is a problem that the flywheel 2 generally has a large structure.

The purpose of this invention is to provide a brake dynamometer that omit the flywheel and torque meter, thereby making the device more compact and inexpensive, and making test operations easier. It is on offer.

The brake dynamometer according to the present invention has a second
The basic configuration is shown in the figure. The drive motor 5, which is made into a DC motor, has a stator side frame 5A supported by a swing bearing 6, and an automatic scale or load cell that engages with the tip of a torque arm 7 protruding from both sides of the frame 5A. The load detector 8 detects the torque that the frame 5A receives between it and its rotor. The rotor shaft 5B of the drive motor 5 is connected to one rotating member such as a drum or shoe of the brake under test 3, and the other rotating member of the brake under test 3 is fixed. In this mechanical system configuration, during a brake test, the rotor of the drive motor 5 is accelerated to the braking start speed, and after the test brake 3 is applied, the brake 3 has the same inertial energy as a conventional flywheel.
The drive motor 5 is provided with a speed control device for controlling the deceleration of the drive motor 5.

FIG. 3 shows an embodiment of the speed control device for the drive electric motor 5 according to the present invention, in which the electric motor 5 has a predetermined deceleration characteristic after the start of braking to obtain a desired flywheel effect. The armature current of the drive motor 5 is controlled by a thyristor forward converter 9, and the initial speed to be set as the brake start speed is determined by the output N of the pulse pickup 10 and the initial speed setter 11.
The output of the speed control amplifier 12 is used as a current command, and the armature current is controlled by the current control system consisting of the current control amplifier 13, the phase controller 14, and the current detector 15, and the initial speed setting value is determined. Feedback control is performed. Initial speed setting device 1
The set value 1 is given to the point where it matches the detected speed value N via the changeover switch 16, and the speed command after the brake operation is given from the function generator 17 as another speed command to the speed control system. Function generator 17
is activated by the switching command Vs of the changeover switch 16, and outputs a speed command of a function having the deceleration characteristic set by the deceleration setting device 18 with the setting value of the initial speed setting device 11 as the initial value.

Therefore, as shown in FIG. 4, the speed of the drive motor 5 is controlled by setting the selector switch 16 to the state shown in the figure and accelerating to the set value No. of the initial speed setting device 11 and speeding up to the set speed at the start of the brake test. No, and at time t ₁ when brake 3 is applied, selector switch 1 is turned on.
6 from the illustrated state and the function generator 1
7 is activated, the speed is controlled by the output of the function generator 17, and by driving the brake 3 based on this speed, the deceleration characteristic is controlled to be the same as that of the flywheel.

FIG. 5 is a configuration diagram of a control device showing another embodiment of the present invention. The difference between this figure and FIG. 3 is that the deceleration is directly set instead of the function generator 17, and the deceleration signal is generated by differentiating the detected speed N of the pickup 10 with a differentiator 19. This deceleration signal is compared with the set value of the deceleration setter 20 and passed through the deceleration control amplifier 21 as a current command for the current control system during brake operation. In addition,
Switches 22A and 22B are switched in synchronization with changeover switch 16.

Therefore, according to the present invention, in order to provide the drive motor with an initial speed adjustment function, a flywheel function, and a torque meter function, the flywheel and torque arm mechanism of the torque meter are omitted compared to the conventional device, and the same structure is used. A small and inexpensive brake tester can be constructed by adding a small control circuit to the drive motor control device and supporting the drive motor frame with a swing bearing. Furthermore, the inertia constant of the flywheel can be set by operating the motor's deceleration setting device rather than by operating the flywheel itself, making it easy and safe to operate in the test room. In particular, since the current command is obtained from the deceleration signal corresponding to the deceleration setting value using the speed setting value as the initial value, there is an effect that the circuit configuration for inertia amount control is simplified.

[Brief explanation of the drawing]

Fig. 1 is a basic configuration diagram of a conventional brake dynamometer, Fig. 2 is a basic configuration diagram of the present invention, Fig. 3 is a circuit diagram showing the control device for the drive motor in Fig. 2, and Fig. 4 is a diagram of the control device of the drive motor in Fig. 3. FIG. 5 is a diagram showing the configuration of another control device for the drive motor in FIG. 2. 1, 5... Drive electric motor, 3... Brake under test, 4... Torque meter, 6... Rocking bearing, 7...
... Torque arm, 8 ... Load detector, 9 ... Thyristor order converter, 11 ... Initial speed setting device, 16 ...
...Selector switch, 17...Function generator, 18,2
0... Deceleration setting device, 19... Differential circuit.

Claims (1)

[Scope of utility model registration request] A drive motor having a stator side frame supported by a swing bearing and measuring the torque applied to the frame via a torque arm provided on the frame; The drive motor is controlled by a speed control system that matches the speed setting value with the speed detection value of the drive motor, and a current control system that controls the armature current of the drive motor using the output of this control system as a current command. means for accelerating the brake to the test speed of the brake under test, and after the start of braking operation of the brake under test, the speed setting value is set as an initial value, and a current command for the current control system is obtained from a deceleration signal corresponding to the deceleration setting value. A brake dynamometer characterized by comprising an inertia control means.