JPH0124248B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an unbalance correcting positioning device.

In order to correct an unbalance in a rotating body, such as a motor rotor, it is first necessary to measure the size and position of the unbalance that exists in the rotor, and then perform correction processing at that position according to the above-mentioned size. There is.

The method of measuring and correcting unbalance is to separate the actual unbalance vector into two components and make corrections on each component, especially when the position where correction is possible is limited to poles, etc., such as with rotors. It is mainly used for rotating bodies.

Another method for measuring and correcting unbalance is a method called the polar coordinate correction method, which is a method of correcting a single point in the direction of the unbalance vector without decomposing it into component force components. . In this method, when modifying the motor rotor, etc.,
Usually, the restriction on the correctable position is resolved by using a drum-shaped milling cutter or the like. According to this polar coordinate correction method, the unbalance can be removed by correcting only one location, which is more efficient than the former method of separating force components and correcting each of them.

By the way, in any of the above-mentioned known correction methods, it is necessary to position the position to be corrected at the installation position of the correction blade after measuring the unbalance.

In the correction method that separates into two components, the correction is performed in two component force directions that sandwich the unbalance vector among multiple component force directions set in advance corresponding to the rotor poles, etc. Positioning stops for this purpose are limited to any one of several component force directions on the rotating body. A method for automatically performing such positioning has already been proposed in Japanese Patent Application Laid-Open No. 49-68786, and it can be used for unbalance measurement without requiring a separate device or procedure for shifting from the reference position to the corrected position. The rotating body that has been rotated is immediately stopped so that the direction of the first component of force to be corrected is directed toward the position where the correction cutter is installed.

On the other hand, in the polar coordinate correction method, the direction in which the rotating body should be corrected is, for example, as in the two-component separation method described above.
The angle is not discrete such as 0°, 90°, 180°, etc., and the technique of JP-A-49-68786 cannot be adopted.
Therefore, conventionally, in the polar coordinate correction method, a method has been adopted in which the rotating body is once stopped at a fixed reference position (zero degree), and then shifted so that the unbalance direction is directed to the installation position of the correction blade. For example, in a device that rotates a rotating body by the friction of a drive belt, this shift is performed after the rotating body is stopped at a zero degree position.
A method is adopted in which the drive belt is driven by a pulse motor by an amount corresponding to the angle based on the unbalance measurement result. However, with this method, accurate positioning is difficult due to slippage between the drive belt and the rotating body, inertia of the rotating body, expansion and contraction of the belt, etc.

An object of the present invention is to provide a device that uses a polar coordinate correction method that requires the positioning of a rotating body at an arbitrary angle, in which a rotating body can be fixed for unbalance measurement without a step of shifting the rotating body. An object of the present invention is to provide an unbalance correction positioning device capable of correctly stopping a correction cutter at a position where the correction cutter is disposed.

The present invention will be described below with reference to drawings of embodiments.

The rotor 1 of the motor has its shaft supported by a bearing to which a vibration detection pick-up 2 is attached,
It rotates by friction with a drive belt 24 driven by a motor 25. The sensor 3 provided close to the outer circumference of the rotor 1 irradiates light onto a pole 23 formed on the outer circumference of the rotor 1, detects the pole 23 from the reflected light, and outputs a pulse signal. be. Note that a proximity switch or the like can also be used as the sensor. The output of the sensor 3 is introduced into a frequency divider circuit 5 via an amplifier 4, and the frequency divider circuit 5 divides the frequency by the total number of poles 23, and transmits the first reference pulse every rotation to a two-component separation circuit 8 and a second reference pulse. This signal is output to the first clock pulse generation circuit 6 and the first counter 7. The first clock pulse generation circuit 6 generates the first reference pulse by a predetermined multiple B (for example,
360) The first clock pulse multiplied by
It is output to the counter 7 of. The first counter 7 counts the first clock pulses using the first reference pulse as a reset signal and outputs the number to the coincidence detection circuit 17.

The pickup 2 detects the vibration of the rotor 1 and outputs an unbalance signal to the two-component separation circuit 8. In the two-component separation circuit 8, the unbalanced signal is DC-converted into two DC signals E ₁ and E ₂ with a phase difference of 90° from the phase relationship with the first reference pulse. These two DC signals are stored in a storage circuit 9 and introduced into a two-component combining circuit 10, respectively. In the two-component synthesis circuit 10, these DC signals are synthesized based on the frequency of the second reference pulse. The second reference pulse generation circuit 11 generates second reference pulses, which are two square wave signals with a phase difference of 90 degrees and have a predetermined frequency ω and are sent to the two-component synthesis circuit 10. Output. One of the second reference pulses includes the position of the sensor 3 and the unbalance correcting device (for example a milling cutter) 28.
A predetermined phase angle A determined by the positional relationship with the installation position of
is added by the phase angle adding circuit 12. The phase difference detection circuit 13 corrects the phase difference between the second reference pulse to which the phase angle A is added and the signal obtained by combining the DC signals E ₁ and E ₂ , that is, the unbalance angle θ ₁ by adding the phase angle A. The time width corresponding to the magnitude of the phase angle θ ₂ is detected and the value is output to the gate circuit 15. Second
The clock pulse generation circuit 14 is a circuit that outputs to the gate circuit 15 a second clock pulse obtained by multiplying the second reference pulse by a predetermined multiple B that is the same as the multiple generated by the first clock pulse generation circuit 6. A square wave signal having a time width of phase angle θ ₂ is output from the gate circuit 15 to the counter 16 .
The second counter 16 counts the second clock pulses corresponding to the time width of the phase angle θ ₂ using the second reference pulse as a reset signal, and stores the value in the storage circuit 30. The coincidence detection circuit 17 determines whether the content of the first counter 7 matches the content stored in the storage circuit 30, and when they match, outputs a coincidence signal to the stop device. The stop device consists of a notch 21 driven by a solenoid 20, which is connected to an SCR element 19, a differential circuit (C,
R) 18 and a switch 29 to the coincidence detection circuit 17. The tip of the notch 21 is made of urethane or the like to protect the surface of the rotor 1.

In the above configuration, the rotor 1 of the motor is rotated at a practical rotation speed, and the unbalance signal generated at that rotation speed is passed through a two-component separation circuit 8, a storage circuit 9, and a two-component synthesis circuit 10, as is known in the art. The signal is converted into a signal having a phase difference of _one unbalance angle θ with respect to the second reference pulse, and is introduced into the phase angle detection circuit 13.

On the other hand, a signal obtained by adding the aforementioned phase angle A to the second reference pulse is introduced into the phase angle detection circuit 13, so its output is a square wave having a time width corresponding to the unbalance angle θ ₁ . Instead, it becomes a square wave having a time width corresponding to the angle θ ₂ obtained by correcting θ ₁ by an angle A based on the arrangement positional relationship between the sensor 3 and the correction device 28 .

The second counter 16 counts the second clock pulses using a square wave with a time width corresponding to θ ₂ as a gate signal, so the memory circuit 30 stores θ ₂ ,
In other words, the value corresponding to the corrected unbalance angle at angle A is stored. For example, a predetermined multiple B
When is 360, the angle (degree) corresponding to θ ₂
That will be remembered.

Next, return the rotation speed to a low speed that can be stopped, and turn switch 2.
Close 9. At this time, the first counter 7 counts the first clock pulse obtained by multiplying this first reference pulse by a factor of B, starting from the generation of the first reference pulse. When the counted value reaches the content of the storage circuit 30, that is, the value corresponding to θ ₂ , a match signal is output. This coincidence signal passes through the differentiating circuit 18 to the SCR element 19.
is input, the solenoid 20 is activated and the notch 21 is
The tip 22 of the rotor 23 contacts the rotor 23 and the rotor 23
rotation is stopped. At this time, since the rotation is stopped at a phase angle that is the sum of the unbalance angle θ ₁ and the phase angle from the rotation start point to the correction position, the unbalance position and the correction position just coincide.

As described above, according to the present invention, in an apparatus using a polar coordinate correction method in which the unbalanced position of a rotating body is corrected once,
There is no need for the conventional process of stopping the rotating body at a fixed point and then shifting it.
A rotating body that is being rotated for unbalance measurement,
The location to be corrected can be immediately positioned and stopped so that it coincides with the installation position of the correction device.
Moreover, with this polar coordinate correction method, the stopping position is 2
Conventionally, even if a shift process was provided, accurate positioning was difficult due to slips, etc., because the components were not installed discretely as in the component force correction method and needed to be stopped at an arbitrary angle. It is also possible to configure the notch to be reliably stopped by a notch driven by the generation of a coincidence signal, so that corrective positioning can be performed with high precision without overrun.

[Brief explanation of drawings]

The drawing is a block diagram showing the configuration of an embodiment of the present invention. 1... Rotor, 2... Pickup, 3... Sensor, 21... Notch, 24... Drive belt.

Claims (1)

[Claims] 1 A rotating body is rotated by the friction of the drive belt, an unbalance signal is detected from the vibration of the rotating body, and the output of a sensor that detects a change in the state of the outer periphery of the rotating body is introduced to detect the rotation of the rotating body. A first reference pulse synchronized with the rotation is generated, and from the first reference pulse and the unbalance signal, this first reference pulse is generated.
Two types of DC signals related to the phase difference of the unbalanced signal with respect to the reference pulse are derived, these two types of DC signals are synthesized using the second reference pulse, and the synthesized signal and the second By introducing the reference pulse into a phase difference detection circuit and detecting the phase difference, a square wave having a time width related to the phase angle of the unbalanced position existing in the rotating body with respect to the first reference pulse generation position is generated. The signal output device includes a stop device that stops the rotating body upon input of a drive command signal, a correction device disposed in a predetermined positional relationship with respect to the sensor, and a phase difference detection circuit to be introduced into the phase difference detection circuit. a phase angle adding circuit that shifts the second reference pulse by a phase angle determined by the positional relationship between the sensor and the correction device; a first clock pulse generating means that multiplies the first reference pulse by a predetermined multiple; a first counter for counting the output of the first clock pulse generating means; a second clock pulse generating means for multiplying the second reference pulse by the same multiple as the predetermined multiple; and a square clock pulse from the phase difference detection circuit. a second counter for counting the output of the second clock pulse generation means generated within the time width of the wave signal; a memory circuit for storing the counting result of the second counter; and a count value by the first counter. An unbalance correcting positioning device comprising: coincidence detection means for supplying a drive command signal to the stop circuit when the information matches the contents stored in the memory circuit.