JPS59155083A - Controller for carrier-feeding stepping motor in printer - Google Patents

Abstract

PURPOSE:To enable to determine a timing in accordance with data, by a method wherein a micro-processor provided with time interruption and a timer on which data for controlling time can be preset are used for determining the timing of changing over an energizing phase for a motor. CONSTITUTION:A timing for the stepping motor M2 for feeding a carrier is generated by a programmable timer 24, and time interruption is demanded of a CPU 22. The CPU 22 incorporates a micro-processor provided with time interruption, processes time interruption, processes a counting demand made by a type selection detector 25, and gives an energizing phase command to a stepping motor driving circuit 26. The micro-processor incorporated in the CPU 22 and the timer 24 are used to accelerated and decelerate at a constant acceleration, and timing is controlled by setting respective timer data for each speed- changing stage, whereby a speed change in a trapezoidal shape or a triangular shape symmetrical on the left and right sides is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Rearward Field of the Invention] The present invention relates to a stepping motor control device for carrier feed 9 in a printer.

[Background technology of the invention and its problems]

Conventionally, in a printer using a stepping motor as a motor for feeding the glaze carrier, the stepping motor is controlled in a first mode, as shown in FIG. (α
), a voltage controlled oscillator (1) is used, and the input voltage N is controlled by the CPU and generated from the voltage generating circuit (Figure 1 G) generated from the voltage controlled oscillator (1). By varying the clock frequency, the output frequency f as shown in FIG. 1(C) is obtained. Generate tTT and drive circuit (3)
The stepping motor (4) is accelerated or decelerated through the One-shot timer Tr s for timing
T2, Ts C5), etc. were used to adjust the timing to obtain a good damping characteristic as shown in FIG. 2C). However, in this method, since it is necessary to switch between the two modes at the node level, the circuitry is complicated and there is no flexibility in timing.

[Purpose of the invention]

In view of these points, the present invention uses a microprocessor with a time interrupt and a timer capable of serially resetting data that can be controlled by time t for the excitation phase switching timing of the stepping motor for carrier feeding. 9, the present invention provides a stepping motor control device for carrier feeding in a printer which has a flexible circuit configuration as shown in FIG. 9 and whose timing can be determined by data.

[Summary of the invention]

The present invention provides a printer that uses a stepping motor as a carrier feeding motor, which uses a microprocessor with a time interrupt and a timer that can preset data that can control the time at the timing of excitation phase switching of the stepping motor. It is made by using it.

[Embodiments of the invention]

Next, an embodiment of the present invention will be described with reference to FIGS. 3 to 9.

First, in FIG. 3, ul) is a platen rotated by a paper feed motor ←, and the print head CL3, which performs printing operations opposite to this platen μD, overflows into a guide frame (not shown) and reaches the platen circle. It is provided so as to be movable in parallel to the width direction. Further, the head 0 has a hammer circle that performs an engraving operation on the platen circle, and is also equipped with an ink ribbon IIω, a print wheel QO, and a type selection motor (:L) that rotates this wheel uQt. Further, the head Q) is suspended between a pair of left and right data IJ (1→C1), and a wire 12ρ is wound and engaged with the rotating shaft (20α) of the carrier feed Q motor (A) in the middle. Both ends of the wire (c) are connected, and the wire (c) is driven by the carrier feeding motor (4).
is retracted, and the head (to) is moved in the left-right direction along the platen circle.

In addition, in FIG. 4, a DC servo motor (Ml) is used for the alpha force of the type selection motor, and is controlled in a closed loop, and the carrier feeding motor (A) and the paper loading motor (12 are the stepping motors). Motor (Mz) (Ms
) are controlled in an open loop using the CPU (a).
An excitation command is given by. Further, a RAM- having various memory areas is connected to the CPU (a), and a programmable timer (c) as a timer that can preset data for controlling time is connected. This programmable timer (c) is connected to the stepping motor (
N2) timing is generated and a time interrupt request is made to the CPU (a). In addition, various types of time occur. Furthermore, the CPU) is a microprocessor (not shown) f with time interrupts.

It is built-in, performs time interrupt processing, processing for requesting the count from the type selection detector
This is done together with the interface with the outside world.

Here, the rotational speed ω of the motor (M2) changes over time t
As shown in FIG. 5 (α), it has a trapezoidal shape that is bilaterally symmetrical. That is, the blade was accelerated from the start position at a constant speed at the blade edge for a certain period of time, and then decelerated at a constant speed at the door speed for a certain period before stopping, thereby stopping at the target position. In this way, when the acceleration, rotational speed, and rotational speed ω become 0, the stellar angle θ, that is, the rotation angle θ, matches the result of the trapezoid. Note that when the target position is reached at t3 or t4, the speed change becomes trapezoidal, but the lifting platform that reaches the target position at tl or t2 does not have a constant speed stroke and enters a deceleration stroke in the middle of the blade mouth speed stroke. The velocity change is in the form of an isosceles triangle.

For example, in Fig. 5C), when the start position is 00 and the target position is θ3, consider the change in rotational speed ω with respect to the change (rotation angle) θ when rotating from 00 to θ3 and stopping. to θ1 with constant acceleration, and θ1
The speed is constant from θ2 to θ2, and deceleration is constant from θ2 to θ3. That is, by accelerating and decelerating at a constant acceleration, the angular velocity with respect to the angle (i.e., rotational speed ω) is proportional to the square root of the displacement angle (i.e., position change θ).

Therefore, in order to accelerate and decelerate the speed at a constant acceleration, a microprocessor in the CPU () and the programmable timer (c) are used, and timer data is set for each shift stage. The timing was controlled to obtain a symmetrical trapezoidal or triangular speed change as shown in FIG. 5 (α).

In addition, in order to obtain the timer data, FIG. 6 (cL
), the number of steps n of the motor (M2) during acceleration and deceleration is
The relationship between (displacement angle) and timer time T is shown.

Based on this one gear, the number of gears is divided into a total of N gears from the initial speed to the maximum speed, from 1 to N, and the timer time T1, T2, TN for each is read, and the RAM ( Shift stage 1.2, -1--1N is set in the address area (A) in the data area (C).
The timers TI, T2, ---1TN are associated with each other as shown in FIG. 6(a)).

That is, line B11 in FIG. 6(α) has been replaced with data in FIG. 6(4)).

Here, addresses 1 to 3 when the number of gears is N-36.
An example of the timer data T1 to T36 referenced in 6 is shown in the table below. However, timer data is time (msec)
It is expressed as

Regarding the damping of vibration immediately after the carrier part stops, the timing according to the formula is not necessarily satisfactory, so by using the fact that the timing can be controlled with data, we conducted an experiment as shown in Figure 7 to reduce the vibration damping immediately before the stop. Time T1, T! I decided.

Experimentally, if the timing of count 5 is set near the time when the overshoot reaches the top of the gills using clocks 1, 2, 3, and 4, the vibration will be reduced. Other values from T3 to 136 were obtained from theoretical values.

Here, the microprocessor selects an address appropriately according to the relationship between the current position (Y) and the destination position (3) according to the flowchart of FIG. 9, and reads the timer data referenced by that address from the RAM H. Then, the programmable timer (c) is set, and other processing is performed until a time interrupt occurs.Next, the flowchart of FIG. 9 will be explained.

Here, a destination position address counter C and a deceleration start flip-flop D are respectively provided in the RAM (c).

First, in the initial installation, clear the timer data address counter C, calculate X-Y'i, and set the motor (M2).
Check the direction of rotation and set the number of pulses to be sent in register A.
Store in. Next, the contents of register A are calculated to be 1 and stored in register B.

At this time, numbers below the decimal point are rounded down. Further, the contents of the target position address counter X are transferred to the current position address counter Y, and the deceleration start flip-flop D is reset.

Next, when the conditions of C<B and C<36 are satisfied, acceleration is started, the value of C is incremented, and A
decrements the internal value of , generates a clock at the l10-port, and sets the timer data designated by C referred to above in the programmable timer (c). In other words, take the flow of (7) (a), (b)), (a), and (g).

Then, each time a time interrupt signal is received from this programmable timer (c), under the condition that ANO and D are reset, the contents of C are incremented and the timer data is updated. The process of decrementing the immanence of A, that is, the flow of (e), (7), (i), (i), (i), (g), is repeated, and acceleration is continued until C=36.

However, if B≦36 in the initial setting, C≦3
At 6, C=B, 9, at this time set D and enter deceleration,
The entire contents of C are decremented, the timer data is changed, and the contents of A are decremented. That is, (a) (b) (7)
Take the flow of (to) (b) (b) (goods) to) (b). Then, by the time interrupt, the process of decrementing the contents of C and decrementing the contents of A, that is, (1
) ρ) ) (g) (a) (a) (b) Repeat the flow and continue decelerating until A=O. That is, in this case, the acceleration/deceleration strokes shown in FIG. 8 are taken.

Further, in the case where B>36 in the initial setting, when C=36 due to acceleration, D is set and the A>360 condition is satisfied and the equation is entered. In this case, the contents of C decrement the contents of the unchanged binding A. That is, (to) (a)
(7) Take the following flow. Then, the process of decrementing the contents of A by the time interrupt, that is, (1) ρ) (B)) (B)
Return the flow of ψ) to green and keep the velocity constant &' until A=36.
c.

Then, when A=36, the conditions of A≦36 and A≦B are satisfied and deceleration is started, the contents of C are decremented, the timer data is changed, and the contents of A are decremented.

That is, ←) (a) (ff) (b) (goods)) (6) Φ
) flow. Then, the same flow is repeated by a time interrupt, and the speed is decelerated until A=O.

In this case, the knob takes the acceleration/deceleration strokes shown in FIG. 8.

In this way, by referring to the existence of C and setting data in the programmable timer 04, the simulator (M
, ) are symmetrical with respect to the center of the stroke, as shown in FIG. 8, and stop exactly at the target position. As mentioned above, the timing can be finely adjusted by changing the data, and the acceleration and deceleration can also be programmed using data.

Therefore, the motor (M2
) is operated at high speed or when vibration is an issue such as when moving one pitch, the timing can be controlled by presetting data suitable for each case, providing flexibility. The circuit configuration can be simplified just by using it.

〔Effect of the invention〕

According to the present invention, a microprocessor with a time interrupt signal and a timer that can be preset with data that can control the time are used for the timing of excitation phase switching of the stepping motor for carrier feeding. This change makes it possible to program the acceleration/deceleration speed using data when the stepping motor is used for positioning, and the final clock time can be freely programmed to reduce vibration when stopped. Therefore, it is possible to control the timing by presetting data suitable for each case, such as when the motor is operated at high speeds such as during carrier return, or when vibration is a problem such as during one-pitch feed, thereby providing flexibility. Moreover, the circuit configuration can be simplified by only using a microprocessor and the above-mentioned timer. Furthermore, the remaining processor capacity can be used to control the position of the motor for character selection and to send and receive signals to and from the outside.

[Brief explanation of drawings]

Figure 1 (α) is a block diagram showing a conventional timing generation circuit during high-speed operation of a stepping motor, ω) is a diagram showing the input voltage of the voltage controlled oscillator shown above, and Figure 1 (C) is a diagram showing the input voltage of the voltage controlled oscillator shown above. Diagram showing output frequency, summary 2 diagram (cL)
3 is a block diagram showing a timing generation circuit when a conventional stepping motor is fed by one pitch; FIG. Figure 4 is a block diagram showing the circuit configuration of the above, and Figure 5 (cL) is a graph showing speed changes over time of the stepping motor according to the present invention.
Figure 6 (α) is a graph showing the change in speed relative to the position change as above, Figure 6 (α) is a graph showing the change in one hour of the timer against the number of steps as above, axis) is a diagram showing the memory area in RAI'/I, Figure 7 FIG. 8 is an explanatory diagram showing an experiment conducted to eliminate vibration when the motor is stopped, FIG. 8 is a diagram showing an acceleration/deceleration process according to the present invention, and FIG. 9 is a flowchart showing timing control of the micro 70 processor. (M2)...stepping motor for carrier feeding,
Q: A CPU with a built-in microprocessor that provides time interrupts. A programmable timer that can be used to preset data.

Claims (1)

[Claims] (1) In a printer that uses a stepping motor as a carrier feeding motor, a microprocessor with a time interrupt 9 and a timer that can reset data that can control time are used at the timing of excitation of the stepping motor @ phase switching. A stepping motor control device for carrier feeding in a printer, characterized by using the following.