JPS6349480B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Problem The present invention relates to a pulse motor drive method for controlling a pulse motor movable element to stop at a desired target position.

Conventional technology Conventionally, as a drive method for a pulse motor that controls the moving element of a multiphase pulse motor (including a linear motor) to stop at a target position, for example, a 4-phase pulse motor with 2-2 phase excitation is used, and a drive method using D and A phase excitation is used. When controlling the mover to stop with DC restraint, when switching the excitation from the C/D phase to the D/A phase, the C phase is simultaneously set for a preset time depending on the mover rotation speed, load conditions, etc. Excite and decelerate and brake the mover,
A method of stopping at a target position is generally known.

However, in the conventional method described above, if the load conditions of the slider change, the slider cannot be controlled to stop at the desired target position, and unnecessary vibrations (damping phenomenon) occur in the slider due to load inertia. Therefore, it takes a long time for the unnecessary vibrations to settle down, and the next operation cannot be carried out immediately.

Purpose The present invention solves the above-mentioned conventional drawbacks.
When controlling the moving element of a pulse motor to stop at the target position, by applying a driving force in the direction opposite to the direction of unnecessary vibration to the moving element that starts unnecessary vibration at the target position, unnecessary vibration is reduced and the convergence time is reduced. The purpose is to provide a pulse motor drive system that can shorten the time required.

Embodiments Hereinafter, embodiments of the pulse motor drive system according to the present invention will be described.

FIG. 1 is an electrical block diagram showing a drive outline of the pulse motor drive method according to the present invention, FIG. 2 is an explanatory diagram showing a stop control state of the mover in a plan view, and FIGS. 1 is a waveform diagram showing main signals in the figure, 1 is a 4-phase pulse motor driven by 2-2 phase excitation, 2 is a mover (rotor) of the 4-phase pulse motor 1, and one end of the mover 2 A disk 3 in which a number of slits 3a are formed corresponding to the movement positions of the disk 3 is fixed to the disk 2a.

The photodetector 4 includes light receiving diodes 4a and 4b arranged to output two detection signals Ss ₁ ÷ Ss ₂ having a phase difference with each other, and a light emitting diode for emitting light to these through a slit 3a. diode 4c
It consists of The detection device 5 detects the movement position of the mover and the forward or backward movement direction from the detection signals Ss ₁ and Ss ₂ , and outputs a movement position signal TPs and a direction detection signal _TDs to the drive control circuit 6, respectively. For example, when the slider 2 moves forward, the detection signal Ss ₁ is delayed by about 90 degrees in phase compared to the detection signal Ss ₂ , and when the slider 2 moves backward, it advances by about 90 degrees, thereby causing the mover 2 to move forward or backward. To detect.

Furthermore, the direction detection signal TDs is composed of a forward signal TDFs that exhibits a high level only during forward movement as shown in FIG. 3A, and a reverse signal TDRs that exhibits a high level only during backward movement as shown in FIG. has been done.

7 is a counter, which counts the count signal Cs inputted from the drive control circuit 6 every time the drive control circuit 6 outputs the drive signal Ds to the distribution circuit 8;
When the counted value reaches the number set by the movement amount instruction signal TIs, a disconnection signal STs is output to the drive control circuit 6, and the output of the drive signal Ds is stopped. Based on the input signal Is, the drive control circuit 6 first outputs a drive signal Ds for exciting the first two excited phases of the pulse motor 1 to the distribution circuit 8. The generated movement position detection signal TPs is fed back and the drive signal Ds is sequentially self-oscillated and output to the distribution circuit 8. Distribution circuit 8
are the contents of register 8a and the direction detection signal
Excitation signals PAs to PDs are applied to excitation phases A, B, C, and D, respectively, in accordance with the instruction of the movement direction by TDs, and the mover 2 is moved toward the target position DP.

When the drive control circuit 6 is stopped, for example, after exciting the excitation phases C and D, when the above-mentioned disconnection signal STs is generated when the excitation phases D and A are excited, the drive control circuit 6 distributes the final drive signal FDs based on this. Output to circuit 8.

As a result, the distribution circuit 8 continues to excite the excitation phases D and A using the final excitation signals FPDs and FPAs shown in FIG. As shown in the figure, the load inertia generates unnecessary vibrations F that repeatedly move forward or backward against the DC restraint before and after the target position DP.

Therefore, the drive control circuit 6 uses the final drive signal FDs.
The direction detection signal TDFs continues to be output.
Immediately after detecting the reversal position where the mover 2 reverses from forward to reverse due to the change from HIGH to LOW,
A stop drive signal SDs having a plurality of chopping pulses as a constituent unit is outputted to the distribution circuit 8 for a predetermined time _t4 , and the distribution circuit 8 refers to the contents of the register 8a and the instruction contents of the direction detection signal TDs. Mover 2
A stop control signal SCBs for energizing the non-excited phase B arranged in the opposite direction to the moving direction, that is, on the forward side.
is applied to excitation phase B.

This applies a driving force to the mover 2 in the direction of its movement, that is, the backward direction, and the mover 2
Decrease the width of the retreat.

Next, when the mover 2 reverses from backward to forward, the drive control circuit 6 changes from HIGH of the direction detection signal TDRs.
Immediately after detecting the reversal position by changing to LOW,
Outputting a stop drive signal SDs with a smaller number of pulses than the above-mentioned stop drive signal to the distribution circuit 8 for a predetermined time _t2 ,
Similarly, the distribution circuit 8 applies a stop control signal SCCs to the excitation phase C to excite the non-excitation phase C arranged on the backward side. This applies a driving force to the movable element 2 in the direction opposite to the forward moving direction, thereby reducing the forward movement width of the movable element 2.

Immediately after the mover 2 is located at the inverted position by repeating the above operation, the drive control circuit 6 sequentially outputs the stop drive signal SDs that sequentially decreases the number of pulses and the output time _t3 to _t5 , and starts the excitation phase. B and C are alternately excited to reduce the movement width of the mover 2.

The mover 2 then stops at the target position DP, and is held stopped by the excitation of the excitation phases D and A.

Furthermore, the two signals that make up the direction detection signal TDs
Since TDFs and TDRs are both at LOW at this point, the drive control circuit 6 detects that the mover 2 is in a stopped state and instructs the next operation.

Therefore, in the pulse motor drive system of this embodiment, when the mover 2 is DC-constrained by the excitation of the excitation phases D and A, the unnecessary vibration F generated in the mover 2 is suppressed by a driving force in the direction opposite to the moving direction of the mover 2. The movable element 2 can be stopped in a single period of time by alternately exciting the non-excited phase B or the non-excited phase C at the position where the oscillation is applied and applying a driving force in the opposite direction.

Effects As explained above, the present invention excites the excitation phases of the pulse motor in a predetermined order to move the mover toward the target position, and also uses a final excitation signal to stop and hold the mover at the target position. In the pulse motor drive method, when a stop control signal is applied to the excitation phase for stopping and holding, a stop control signal is applied to the non-excited phase other than the excitation phase to reduce unnecessary vibrations before and after the target position of the slider. a direction detection device for detecting the moving direction, and a de-energizing device for applying the stop control signal each time the direction detecting device detects a reversal of the moving direction of the mover while the final excitation signal is being applied. By changing the phase and applying a driving force to the mover in the opposite direction to its moving direction, unnecessary vibrations at the target position of the mover can be reduced, the mover can be stopped at the target position for a short period of time, and the desired next This realizes a pulse motor drive system that allows smooth operation.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, and FIG. 1 is an electrical block diagram showing a driving outline of the pulse motor drive method according to the present invention, and FIG. 2 is a two-dimensional diagram showing the stop control state of the mover. Explanatory diagrams shown in Figure 3 A~
F is a diagram of signal waveforms at various parts in FIG. 1. 1 is a pulse motor, 2 is a slider, 5 is a detection device, 6 is a drive control circuit, 7 is a counter, 8 is a distribution circuit, A to D are excitation phases, FPAs and FPDs are final excitation signals, PAs to PDs are excitation Signals, SCBs, and SCCs are stop control signals, TDs is a direction detection signal, DP is a target position, and F is a curve showing unnecessary vibration.

Claims (1)

[Claims] 1. Exciting the excitation phases of the pulse motor in a predetermined order to move the mover in the direction of the target position,
When the final excitation signal is applied to the excitation phase for stopping and holding in order to stop and hold the mover at the target position,
In a pulse motor drive method that applies a stop control signal to a non-excited phase other than the excited phase to reduce unnecessary vibrations before and after the target position of the moving element, a large number of motors move in synchronization with the moving element and in the direction of movement. a detection unit that detects the detection unit and outputs two types of detection signals with different phases when the detection unit moves; and a detection unit that detects the detection unit when the detection unit moves and outputs two types of detection signals with different phases; and a direction detection device for detecting the moving direction of the movable child, and applying the stop control signal each time the direction detecting device detects a reversal of the moving direction of the movable child while applying the final excitation signal. A pulse motor drive system characterized in that unnecessary vibrations at a target position of a moving element are reduced by changing the non-excited phase of the moving element and applying a driving force to the moving element in the opposite direction to the moving direction of the moving element. 2 Claim 1, characterized in that the stop control signal has a plurality of pulse signals as one constituent unit.
Pulse motor drive method described in section.