JPH0725649Y2 - Electric dynamometer calibration device - Google Patents

Description

[Detailed Description of the Invention] A. Field of Industrial Application The present invention relates to a calibration device for an electric dynamometer.

B. Outline of the Invention In the calibration device according to the present invention, a calibration arm is attached to one side of the oscillator of the electric dynamometer, and the tip of the calibration arm is connected to the vicinity of the rotation center of the oscillation link for attaching the calibration weight. As a result, by properly attaching the calibration weights to both ends of the swing link, the swing can be calibrated in both forward and reverse rotation directions.
Due to the boosting action of the oscillating link, a large amount of weight can be calibrated with a lightweight calibration weight, which enables downsizing of the calibrating device and facilitation of calibration work.

C. Conventional Technology An electric dynamometer is generally used as a power test device used for power tests of engines and vehicles.

FIG. 2 shows an entire engine dynamometer (hereinafter referred to as an engine dynamo) as an example of a power test device. In the figure, an electric dynamometer 1 is a levitation bearing 3 on a bed 2.
The oscillating member 4 is rotatably supported by the oscillating member 4, while the shaft 5 of the rotator (not shown) is rotatably supported by the oscillating member 4. A torque arm 6 is horizontally attached to the front surface of the oscillator 4, and a load cell 7 as a load measuring means is interposed between the tip of the torque arm 6 and the bed 2. The shaft 5 of the rotor is connected to the output shaft 10 of the engine 9 via the coupling 8.

In this engine dynamo, the rotor is rotated by driving the engine 9, and the oscillator 4 is swung by the electromagnetic induction action. The swing torque of the oscillator 4 is measured by the load cell 7, and the output of the engine 9 and the rotation torque are calculated based on the indicated value.

By the way, the load cell 7 converts a compressive load or a tensile load into an electric signal to measure the torque of the oscillating body in both the forward and reverse rotational directions. Generally, however, as the number of tests is repeated, a measurement error gradually occurs. come. Therefore, in order to perform the power performance test accurately, it is necessary to appropriately perform error check, that is, calibration.

FIG. 3 is a perspective view of an electric dynamometer equipped with a calibration device for performing calibration.

As shown in this figure, the conventional calibration device has the calibration arms 11 and 12 attached to the left and right of the oscillator 4 and the calibration arms 11 and 12, respectively.
It consists of a calibration weight 13 attached to the end of 12.
In the illustrated example, since the calibration weight 13 is suspended from the calibration arm 11 on the side opposite to the load cell 7, that is, on the left side, a counterclockwise rotational force is generated in the oscillator 4, and the torque arm 6 is generated in the load cell 7. A simulated load P in the tensile direction acts via the. Then, at this time, the measured value (displayed on the display panel 14 via an amplifier (not shown)) indicated by the load cell 7 and the rotational torque corresponding to the simulated load P acted on the oscillator 4 are indicated by the load cell 7. It is checked whether or not it is normal by comparing it with a power value (calculated in advance). When performing compression side calibration, the right side calibration arm 12
The calibrating weight 13 is suspended at the upper part of the oscillating body 4, and a clockwise rotational force is generated in the oscillating body 4 to perform the calibrating.

D. Problem to be Solved by the Invention By the way, the above-mentioned conventional calibration device has the following problems.

The calibration of the electric dynamometer is performed before carrying out a performance test of the vehicle, and the range of calibration is naturally the power measurement range in the performance test. However, in recent years, the engine performance has been remarkably improved (the output and the torque are increased), and thus it is necessary to measure a large amount of power even with an electric dynamometer. As a result, a large load has to be applied to the load cell 7 at the time of calibration, and the weight of the calibration weight 13 is often used.

For example, in the illustrated example, the distance between the rotation center of the oscillator 4 and the load cell 7 (L _{1 in the} figure), the rotation center and the calibration arm 1
The ratio of the distance between the tips of 1,12 (L _{2 in the} figure) (hereinafter referred to as the lever ratio of the arm) R ₁ is 1: 2, but in order to apply a load of 300 kg to the load cell 7, weigh 150 kg. A weight 13 is used. Therefore, it takes a lot of labor and time to carry and attach the calibration weight 13, and there is a risk of dropping the weight.

In addition, in order to measure both the tension and compression directions of the load cell 7, it is necessary to individually install the calibration weights 13 on the left and right calibration arms 11 and 12, which requires a large number of man-hours for setup and movement of workers. It was

In addition, the calibration arm 1
Although 1 and 12 are also lengthened, a large work space must be provided on both sides of the oscillating piece 1, which is a problem in terms of equipment.

E. Means for Solving the Problem Therefore, in the present invention, the link support member integrally attached to the fixed portion of the electric dynamometer and the center part swingably supported by the link support member and at both ends are provided. A swing link formed with a mounting portion for a calibration weight, a calibration arm having one end integrally attached to a swing element of an electric dynamometer and the other end connected to a swing center of the swing link. An electric dynamometer calibration device, comprising: a load measuring device arranged between the fixed part of the electric dynamometer and the oscillating device to measure a rotational torque of the oscillating device. Is.

F. Action When a calibration weight is individually attached to the mounting part at the end of the swing link, rotational torque in both forward and reverse rotation directions is generated in the oscillator via the calibration arm, and a positive and negative load measurement means is simulated. Load acts. Then, due to the boosting action of the swinging link, a large-capacity calibration is performed with a lightweight calibration weight.

G. Embodiment One embodiment of the present invention will be described below with reference to the drawings.
In the description, the same members as those of the conventional device described above are designated by the same reference numerals to avoid redundant description.

FIG. 1 shows a perspective view of an electric dynamometer equipped with a calibration device according to the present invention.

As shown in this figure, in this embodiment, a relatively short calibration arm 11 is attached only to the left side of the oscillator 4. Below the calibration arm 11, a link bracket serving as a link supporting means integrated with the bed 2 serving as a fixed portion of the electric dynamometer.
An oscillating link 16, which is rotatably supported in the central portion by 15, is arranged at a right angle to the calibration arm 11. The tip of the calibration arm 11 is linked and linked via a joint 17 to a position slightly offset from the center of rotation of the swing link 16.

Although mounting holes 16a and 16b for mounting the calibration weight 13 are formed at both ends of the swing link 16, in this embodiment, the distance between the center of rotation of the swing link 16 and the joint 17 (in the figure, l ₁ ) And the ratio (l _{2 in the} figure) of the distance between the center of rotation and the mounting holes 16a and 16b (hereinafter referred to as the link lever ratio) R ₂ is 1: 4. On the other hand, in this embodiment, since the calibration arm 11 is shorter than the conventional device described above, the lever ratio R _{1 of the} arm is
It becomes 2: 3.

Next, the operation of this embodiment will be described.

To perform calibration on the compression side of the load cell 7, the calibration weight 13 is attached to the attachment hole 16a on the front side of the swing link 16. Then,
A clockwise rotational force is generated in the oscillator 4 via the joint 17 and the calibration arm 11, and the torque arm 6 is applied to the load cell 7.
A compressive load P acts via the.

Assuming that the weight of the calibration weight 13 is W, the compression load P at this time is
From the lever ratio R _{1 of the} arm and the lever ratio R _{2 of the} link, P = 3/2 × 4/1 × W = 6 × W. Therefore, the weight of the calibration weight 13 required to apply a load of 300 kg to the load cell 7 is 50 kg, which is significantly lighter than the conventional one.

Further, when performing the calibration on the tension side of the load cell 7,
The calibration weight 13 is attached to the mounting hole 16b on the back side of the swing link 16. Then, a counterclockwise rotational force is generated in the oscillator 4,
A tensile load acts on the load cell 7 with the same boosting ratio as on the compression side.

As described above, in the calibration device of the present embodiment, the lightweight calibration weight enables large-volume calibration work, and the calibration arm
Since 11 is short and only on the left side of the oscillator 4, as shown in the figure, the size of the device can be greatly reduced. Also,
Since the calibration work can be performed only on the left side of the oscillator 4, the man-hours required for the setup and the movement of the worker are reduced.

The scope of application of the present invention is not limited to this embodiment, and may be applied to, for example, an automatic calibration device in which a calibration weight is attached to and detached from a swing link by a hydraulic or electric actuator. Further, in the present embodiment, the lever ratio of the arm and the lever ratio of the link are specified for convenience of explanation, but these should be set arbitrarily. Further, although the joint is used to connect the calibration arm and the swing link in this embodiment, other connecting methods may be used.

H. Effect of the Invention According to the calibration device for the electric dynamometer according to the present invention, the calibration arm is attached to only one side of the oscillator, and the tip of the calibration arm is connected near the rotation center of the oscillation link. The following effects are achieved.

Since the calibration arm is short and only one side of the oscillator is required, the calibration device can be downsized and the space can be saved.

A large amount of weight can be calibrated with a lightweight calibration weight due to the boosting action of the oscillating link, which reduces the man-hours for transporting and mounting the calibration weight and also reduces the risk of dropping.

Since the calibrating of the oscillating body in both the forward and reverse rotation directions can be performed on one side of the oscillating body, the man-hours required for setup of the calibrating work and movement of the operator are reduced.

[Brief description of drawings]

FIG. 1 is a perspective view showing an electric dynamometer to which an embodiment of a calibration device according to the present invention is attached. 2 is an overall view of the engine dynamometer, and FIG. 3 is a perspective view showing an electric dynamometer equipped with a conventional calibration device. In the figure, 1 is an electric dynamometer, 2 is a bed, 4 is an oscillator, 6 is a torque arm, 7 is a load cell, 11 is a calibration arm, 13 is a calibration weight, 15 is a link bracket, 16 is a swing link, 17 Is a joint.

Claims (1)

[Scope of utility model registration request] 1. A link support member integrally attached to a fixed portion of an electric dynamometer, a center portion swingably supported by the link support member, and mounting portions for calibration weights formed at both ends. A swinging link, a calibration arm having one end integrally attached to a swinger of the electric dynamometer and the other end connected to the swinging center of the swinging link, the fixing portion of the electric dynamometer, and the A calibration device for an electric dynamometer, comprising: a load measuring device arranged between the oscillator and the rotational torque of the oscillator.