JP3273836B2 - Encoder signal output method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an encoder signal output method, and more particularly, to outputting a preload signal indicating a state of coarse accuracy at the time of turning on a power supply and a subsequent precision accuracy so that a high precision control is performed on a control device side. The present invention relates to a novel improvement for enabling easy determination of whether to switch to the control mode and efficient control.

[0002]

2. Description of the Related Art Conventionally, as an encoder signal output method of this kind, generally, in order to increase the resolution of an absolute encoder signal, tracks for the number of bits are formed on a code plate, and the precision of the signal is increased. I was getting the encoder signal.

[0003]

Since the conventional encoder signal output method is configured as described above, there are the following problems. That is, if tracks for the number of bits are formed on the code plate, it becomes extremely expensive and
The receiving circuit on the control device side also has a complicated configuration, which is an obstacle to miniaturization and cost reduction.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and in particular, by outputting a preload signal indicating a state of coarse accuracy at the time of turning on the power and a state of the fine accuracy thereafter, the control device side. Therefore, it is an object of the present invention to provide an encoder signal output method capable of easily determining when to switch to high-precision control and performing efficient control.

[0005]

An encoder signal output method according to the present invention is directed to an encoder signal output method in which an encoder signal is output from an encoder provided on a rotating shaft of a motor having U, V, and W phase coils. From the time when the initial value at the time of turning on the power is output until the time when the motor is re-initialized, the motor is started with an encoder signal having a coarse resolution of at least 3 bits required as magnetic pole data of the motor and H indicating coarse accuracy. Outputs a level preload signal,
The preload signal is set to L level by the Z phase strobe signal from the encoder, and the A phase from the encoder is
This is a method of counting the B-phase incremental signal to obtain the encoder signal with high precision.

[0006]

In the encoder signal output method according to the present invention, for example, a, b in the U, V, W phases in FIG.
When the power is turned on at the axis position between the points a and b, the center value between the points a and b is output as an initial value and a preload signal is output. The signal goes to L level and U,
The data of the V and W phases are re-initialized and output, and thereafter, the axis data can be output with high resolution and high precision using the A and B phases which are the fine signals. Therefore, an H-level preload signal indicating coarse accuracy is output from the time when the initial value at the time of initial power-on is output to the time when re-initialization is performed,
When outputting axis data consisting of encoder signals based on the precision A-phase and B-phase incremental signals, it has a function to output an L-level preload signal. Therefore, it is necessary to determine the H and L levels of the preload signal. By
The controller can know when to switch to the high-accuracy control, and can perform efficient control.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the encoder signal output method according to the present invention will be described below in detail with reference to the drawings. In FIG. 1, reference numeral 1 denotes a U, V, W phase signal 2a, 2 from a track on a code plate of the encoder of the motor 2.
b, 2c are input units to which the 3-bit U, V, W data 1a from the input unit 1 is input to the load control unit 3 and the counter 4.

The load control unit 3 has a power-on signal 5
And a Z-phase strobe signal 6 from an encoder code plate (not shown). A preload signal 3a is output from the load control unit 3 and a load command 3b is output to a counter 4.

An up signal 10a and a down signal 10b from an up / down circuit 10 are input to the counter 4, and the up / down circuit 10 is provided with an A-phase and a B-phase incremental signal of the rotary code plate. 1
1, 12 are input.

The counter 4 outputs a parallel output 4a as an encoder signal and a serial output 4b as an encoder signal via a parallel / serial converter 13.

Next, the operation will be described. For example, FIG.
When the power is turned on at the axis position of the rotating shaft (not shown) of the motor between a and b of the U, V and W phase data 1a at
The parallel output 4a is set with the center value between a and b as an initial value.
Alternatively, it is output as a serial output 4b and c between a and b is output.
, That is, after passing through the Z-phase strobe signal 6, the preload signal 3a changes from the previous H level to the L level. After that, the U, V, and W phase data 1a is reinitialized and output, and then the parallel output 4a and the serial output 4b with high resolution precision using the A and B phase incremental signals 11 and 12, which are precision signals. Can output axis data.

Therefore, during the period from when the initial value at the time of initial power-on is output to when the motor is re-initialized, the motor is started with the minimum required resolution of 3 bits or more as the magnetic pole data of the motor and the coarse accuracy is obtained. The H-level preload signal 3a is output to indicate that this is the case. The axis data consisting of the encoder signal consisting of the parallel output 4a or the serial output 4b based on the precision A-phase and B-phase incremental signals 11 and 12 is the same as the axis data of FIG. It is output as shown in the angle characteristic diagram.
When this axis data is being output, the preload signal 3a is at the L level. Therefore, it is possible to determine whether the encoder signal is coarse or precise, depending on which level of the preload signal 3a is L or H, and the control device (not shown) can reliably and easily perform the control operation. Is what you can do. Although not shown, the present embodiment uses a motor encoder in which an encoder is coupled to the rotation shaft of the motor described above.

[0013]

Since the encoder signal output method according to the present invention is configured as described above, the number of tracks on the code plate can be reduced, and a high-resolution absolute encoder can be provided in a small size and at low cost. In addition, the state of coarse accuracy at power-on and the accuracy after that can be determined using the preload signal, and it is easy to know when to switch to high-precision control on the control device side, and control efficiently and smoothly You can do it.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an encoder signal output method according to the present invention.

FIG. 2 is a waveform diagram during operation.

[Explanation of symbols]

3a Preload signal 4a, 4b Encoder signal (parallel output, serial output)

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H02P 6/16 G01D 5/245 H03M 1/24

Claims (1)

(57) [Claims] An encoder signal (4a, 4a, 4a, 4b, 4b, 4b) is provided from an encoder provided on a rotating shaft of a motor having U, V, W phase coils.
In the encoder signal output method which outputs the signal b), an encoder having a minimum resolution of 3 bits or more required as the magnetic pole data of the motor from the time when the initial value at power-on is output to the time when the initialization is performed again. It starts with the signals (4a, 4b) and outputs an H level preload signal (3a) indicating coarse accuracy. The Z phase strobe signal (6) from the encoder changes the preload signal (3a) to L level. A and B phase incremental signals from the encoder
(11,12) is counted and the encoder signal (4
a, 4b) obtaining an encoder signal output method.