JPH0523379B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Field of Industrial Application> The present invention relates to a balance tester, and more particularly to a balance tester of a type in which a specimen is fixed to one end of a rotating main shaft and rotated.

<Prior art> In the above-mentioned balance test machine, the specimen is fixed to the end of the rotating main shaft via an adapter,
In this state, the unbalance vector of the specimen is determined from the unbalance signal generated by rotating the rotating main shaft. Therefore, unbalance on the rotating main shaft side,
It is necessary to compensate for the eccentricity between the center of the specimen and the center of rotation of the rotating main shaft.

Conventionally, to explain the principle of this type of compensation, prior to the test, the specimen is attached to the rotating main shaft via an adapter and rotated, and the unbalance due to the above-mentioned eccentricity is detected. Find the balance vector, then adjust the mounting direction of the specimen to 180°.
Rotate it and find the unbalance vector in the same way.
When the two types of unbalance vectors obtained are added, the true unbalance vector existing in the specimen is canceled, and the remaining vector 〓
is twice the vector that is the sum of the unbalance due to eccentricity of the specimen and the unbalance vector existing on the rotating seed axis side. Therefore, by finding the electric signal corresponding to this -1/2〓 vector and adding it to the measured unbalance vector, the true unbalance vector of the specimen can be obtained.

<Problems to be Solved by the Invention> According to the conventional compensation method, the eccentricity of the specimen due to processing errors of the adapter, etc. and the unbalance of the rotating main shaft side including the adapter are compensated for at the same time. If there is no moving part on the rotating spindle side, the above-mentioned compensation signal is effective for a long time, but after an automated balance test, an automatic chucking mechanism for the specimen is adopted on the spindle side, and the moving part is exist. Therefore, the unbalance on the rotating main shaft side changes over time, albeit slightly. In order to compensate for this change, it is necessary to find the vector 〓 mentioned above at a predetermined period, but this work involves a lot of manual work such as shifting the mounting direction of the specimen by 180 degrees, so it is not possible to automatically This is not possible during operation, and there is a problem in that efficiency is significantly reduced.

An object of the present invention is to automatically monitor the above-mentioned change in unbalance on the rotating main shaft side over time in an automated balance testing machine to which specimens are sequentially supplied, and to reflect this in compensation. , to provide a balance testing machine.

<Means for Solving the Problems> The present invention is characterized by a cycle counter that counts the number of measurements on the specimen, and based on the output of the cycle counter, the handling device A means for rotating the rotating spindle in a state in which the specimen is not fixed by stopping the supply of the specimen, and an unbalance vector existing in the rotating main shaft obtained from the unbalance signal generated when the specimen is not fixed. 2 corresponding to x and y components
A storage means for sequentially updating and storing DC signals of various species, and a signal having an opposite phase to the unbalance signal generated when the rotating main shaft is rotated with the specimen not fixed, using the contents of the storage means. It is equipped with an inverter circuit that generates an AC signal corresponding to , and an arithmetic circuit that adds the output of the inverter circuit to the discrepancy signal that occurs when the rotating main shaft is rotated with the specimen fixed. .

<Function> When the rotating main shaft is rotated without fixing the specimen, an unbalance signal is generated due to the unbalance of the rotating main shaft. When a signal with the opposite phase of this unbalance signal is added to the unbalance signal generated during normal measurement rotation with the specimen fixed, the unbalance vector of the rotational main shaft is canceled. The present invention utilizes this point to automatically measure and update the unbalance of the rotating main shaft that changes over time at each set number of measurements, and generate the above-mentioned anti-phase signal based on the measurement. By adding this to the unbalance signal during normal measurement, the intended purpose is to be achieved.

In other words, each time the number of measurements of the specimen determined by the cycle counter reaches the set number,
The supply of the specimen by the handling device is stopped and the rotating main shaft is rotated with the specimen not fixed, and each time the x and y of the unbalance vector in that state are calculated.
Two types of DC signals corresponding to the components are sequentially updated and stored in the storage means. The alternating current signal generated by the inverter circuit using this memory content and added to the unbalance signal in the subsequent measurement state is therefore based on the actual unbalance of the rotating spindle at a constant period. The signal will be updated to the current signal.

<Example> Examples of the present invention will be described below based on the drawings.

FIG. 1 is a block diagram of an embodiment of the present invention.

The rotating main shaft 1 is rotationally driven by a motor 2. A specimen is fixed to this rotating main shaft 1 via an adapter 1a. An unbalance signal U generated when the rotating main shaft 1 rotates is detected by a pull-up 3 and guided to a synchronous rectifier 6 via operational amplifiers 4 and 5. Rotation reference phase signal J of rotating main shaft 1
is obtained by detecting a reference protrusion or the like provided on the rotating main shaft 1 with a proximity switch 7, and this reference phase signal J is led to a phase circuit 8. The phase circuit 8 uses the reference phase signal J as a carrier,
It is configured to output square wave signals having phase differences of 0°, 90°, 180° and 270° with respect to this signal J, and each having a switching ratio of 180°.

In the synchronous rectifier 6, the unbalance signal U that has passed through the operational amplifiers 4 and 5 is smoothed by chopping it with the 0° and 90° square wave signals from the phase circuit 8, so that the unbalance vector x component,
Obtain DC signals x and y corresponding to the y component. This DC signal is sent to a display and displayed. The above is a known unbalance measurement method using a so-called synchronous rectification method. The rotation of the motor 2 is automatically controlled by a motor drive circuit 9, and the specimen is attached to and removed from the adapter 1a by a handling device (not shown). Being teased. This results in fully automatic unbalance measurement.

The operational amplifier 5 includes an eccentricity compensation signal generator 10.
The output signal from the output signal is introduced, and this output signal is added to the unbalance signal here. This eccentricity compensation signal generator 10 includes a DC voltage generator 10a that generates two types of DC signals, and a 0°
and an inverter circuit 10b that chops and adds 90° square wave signals, and is a compensation circuit based on the conventional compensation method described above. That is, the output of this eccentricity compensation signal generator 10 is:
This is an electric signal corresponding to the above-mentioned -1/2〓 vector, and the magnitude of the output of the DC voltage generator 10a is artificially determined by the above-mentioned procedure. however,
In the embodiment of the present invention, the electric signal corresponding to the −1/2 vector obtained in the same way as in the conventional method includes only the component of the unbalance vector based on the eccentricity of the specimen, as will be described later. , the component of the unbalance vector of the rotational main shaft 1 is not included.

Now, in the embodiment of the present invention, the following circuit is added in order to compensate for the unbalance of the rotating main shaft 1. That is, a cycle counter 11 that counts the number of times the rotating spindle 1 is operated by the motor drive circuit 9 and generates an output when a preset number of times is reached, and a memory that stores input signals based on the output of the cycle counter 11. The circuit 12, the inverter circuit 13 that chops the output of the memory circuit 12 and converts it into an alternating current signal, and the arithmetic amplifier 5 that adds the output of the eccentricity compensation signal generator 10, are provided before the inverter circuit 12, the above-mentioned inverter circuit. 13 to the unbalance signal U, and an amplifier driven by the output of the cycle counter 11 to compare the magnitude of the output of the synchronous rectifier 6 with a preset value. Balance amount determination circuit 1
4 is provided.

When the number of normal measurement operations, in which the rotating spindle 1 is rotated with the specimen fixed, reaches a predetermined number of times, the cycle counter 11 issues a command to the handling device to rotate the rotating spindle 1 without fixing the specimen. let As a result, DC signals x and y corresponding to the x and y components of the unbalance vector present in the rotating main shaft 1 including the adapter 1a are output from the synchronous rectifier 6, but these signals are output from the cycle counter 11. It is stored in the memory circuit 12 according to the command.

Thereafter, normal measurement operation is resumed in which the specimen is fixed and the rotating main shaft 1 is rotated, but at this time, the DC signals x and y stored in the memory circuit 12 are The signal A is converted into an alternating current signal A as shown in FIG.

FIG. 2 shows the process of obtaining the AC signal A in the inverter circuit 13. That is, memory circuit 1
DC signals x and y from 2 are stepped with 180 and 270° square wave signals from phase circuit 8, respectively, to obtain signals x' and y'. Next, these are added to obtain AC signal A. Here, memory circuit 1
The DC signals x and y stored in the rotating main shaft 1 are smoothed by chopping the unbalance signal U generated when the rotating main shaft 1 is rotated with 0° and 90° square wave signals. Since the x and y components of the unbalance vector exist in
The AC signal A obtained as described above is equivalent to the opposite phase signal -U of the unbalanced signal U.

Therefore, during normal measurement with a fixed specimen, the unbalance signal that has passed through the operational amplifier 4 is one in which the unbalance component present in the rotating main shaft 1 is removed.

Therefore, prior to measurement, first, the x and y components of the unbalance of the rotating main shaft 1 are stored in the storage circuit 12 as described above, and then the eccentricity compensation signal generator 10 is used to perform the conventional method. Therefore, when a compensation signal is obtained, since the unbalance component of the rotating main shaft 1 has already been canceled in the stage before the operational amplifier 5, the obtained compensation signal does not reflect the bias of the specimen due to processing errors of the adapter 1a, etc. There is only an unbalanced component corresponding to the core amount. The unbalance component corresponding to this amount of eccentricity hardly changes over time and is effective over a long period of time.

Since the contents of the memory circuit 12 are automatically updated each time a predetermined number of measurements is reached based on the output of the cycle counter 11, the unbalance of the rotating main shaft 1 due to the movable parts present in the rotating main shaft 1 can be detected over time. This makes it possible to provide compensation in response to major changes.

When measuring the x component and y component of the unbalance of the rotating main shaft 1, the unbalance amount determination circuit 14 determines the magnitude, and if it exceeds a predetermined value, it is determined to be abnormal and automatic operation is started. It is also possible to stop the system and issue an alarm.

Further, in the above embodiment, an example was described in which the unbalance of the rotating main shaft 1 is measured only by the output of the cycle counter 11, but for example, if the unbalance measurement results of the specimen are consecutively rejected. It can also be configured to be performed even when the child has grown old.

Furthermore, although an example in which the present invention is applied to a vertical one-plane balance testing machine has been described above, it goes without saying that the present invention can be similarly applied to a vertical two-plane dynamic balance testing machine.

<Effects> As explained above, according to the present invention, the unbalance of the rotating main shaft 1 is automatically measured and stored at a predetermined period, and an opposite phase signal of the unbalance signal of the rotating main shaft 1 is determined from the stored contents. Since the configuration is configured to generate an alternating current signal corresponding to , and add it to the unbalance signal during normal measurement, the unbalance of the rotary main shaft 1 will increase over time due to the presence of movable parts in the rotary main shaft 1. It is now possible to automatically follow and compensate for changes in conditions. This not only improves the reliability of unbalance measurement results obtained through fully automatic operation, but also eliminates the need to stop the automatic cycle and perform complicated work to update compensation values, significantly improving work efficiency.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of the present invention, and FIG. 2 is a diagram showing the process of obtaining an alternating current signal A using an inverter circuit 13. 1...Rotating spindle, 1a...Adapter, 2...Motor, 3...Pickup, 4, 5...Arithmetic amplifier, 6...Synchronous rectifier, 7...Proximity switch, 8
...Phase circuit, 9...Motor drive circuit, 10...
Eccentricity compensation signal generator, 11...cycle counter, 12...memory circuit, 13...inverter circuit.

Claims (1)

[Claims] 1. Synchronously rectifying the unbalance signal generated by fixing the specimens sequentially supplied by the handling device to one end of the rotating spindle and applying rotation, based on the rotation reference phase signal of the rotating spindle. In a device that obtains two types of DC signals corresponding to the x and y components of the unbalance vector existing in the specimen and calculates the magnitude and angle of the unbalance of the specimen, the cycle counts the number of measurements of the specimen. a counter, a means for stopping the supply of the specimen by the handling device every predetermined number of measurements based on the output of the cycle counter and rotating the rotating spindle without fixing the specimen; A storage means for sequentially updating and storing two types of DC signals corresponding to the x and y components of an unbalance vector present in the rotating main shaft obtained from an unbalance signal generated in a stuck state, and the contents of the storage means. Using the A balance testing machine characterized by being equipped with an arithmetic circuit that adds to a misalignment signal generated when a rotating main shaft is rotated with a specimen fixed.