JPH0670597A - Pulse motor controller for printer - Google Patents

Abstract

PURPOSE:To allow the suppressing of heat generation and maintaining of a high throughput of a motor to be compatible with each other under the control of a pulse motor such as a carriage motor, a sheet feed motor, etc., to be used for a printer. CONSTITUTION:An operating time TR of a printer is measured (steps S4-S6, S7), and the driving amount PR of a pulse motor executed during a measuring time is measured (step S7). If a measured value PR of the operating time reaches a predetermined amount PRmax before the time PR of the driving amount becomes a predetermined PRmax (step S9), a waiting time tw of intermittently driving a pulse motor is reduced (step S11). If the value PR of the driving amount reaches the amount PRmax before the value TR of the time becomes the time TRmax (step S8), the time tw is increased (step S11). As a result, the amount to be executed within the time TRmax is controlled so as to converge to a suitable predetermined amount PRmax.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to control of pulse motors such as carriage motors and paper feed motors used in printers.

[0002]

2. Description of the Related Art When a printer is used under a heavy duty condition, heat generation of a pulse motor such as a carriage motor or a paper feed motor becomes a problem. In the printer, these pulse motors are driven intermittently.In the past, however, a long enough waiting time was set between the intermittent driving so that the heat generation of the pulse motor does not become a problem. There is.

[0003]

However, a sufficiently long waiting time between motor drives leads to a reduction in throughput.

Therefore, an object of the present invention is to achieve both suppression of motor heat generation and maintenance of high throughput in controlling a pulse motor such as a carriage motor or a paper feed motor in a printer.

[0005]

An object of the present invention is to measure the operating time of a printer, and to measure the drive amount of a pulse motor executed during the measured operating time.
A pulse motor control device having means for increasing or decreasing the intermittent drive waiting time of the pulse motor so that the quantitative relationship between the measurement value of the operating time and the measurement value of the driving amount satisfies a predetermined constant condition. To be achieved.

[0006]

The operation time of the printer and the drive amount of the pulse motor executed during that time are measured, and intermittent drive between drives is performed so that the quantitative relationship between both measured values satisfies a predetermined condition. The waiting time is increased or decreased. As a result, the drive amount executed within a certain operating time is controlled so as to be equal to or less than a certain value when continuously used under heavy duty conditions. In this case, if the drive amount that is executed within a certain operating time is set in advance so that the highest possible throughput can be obtained within the range that does not cause the problem of heat generation of the pulse motor, heat generation can be suppressed. It is possible to satisfy both requirements of maintaining high throughput.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention configured as a control device for a paper feed motor will be described below with reference to the drawings. In general, the control of the paper feed motor is performed by a print engine control microcomputer installed in the printer. The present invention can be carried out by using a microcomputer having such known hardware and loading a program that causes the functions according to the present invention to play.

FIG. 1 shows the control operation of the microcomputer in one such embodiment.

The control is started by turning on the power of the printer (step S1). First, the internal time tint is zero, the paper feed amount count PR is zero, the operating time count TR is zero, and the paper feed interval is between paper feed. Wait time tw is 20
Initially set to m seconds (step S2).

Next, it is judged whether or not the paper is to be fed by a command from the host computer (step S3). When the paper is not fed, the internal time tint is counted as the count time t.
It is determined whether or not cnt has been reached (step S4). Here, the count time tcnt is a predetermined time interval for incrementing the operation time count TR by 1. In this embodiment, tcnt = 6.71 ± 0.2 ms. Now, in step S4, when the internal time tint has not yet reached the count time tcnt, a predetermined increment Δt is added to the internal time tint (step S4).
5). Here, the increment Δt is the time required for the processing in steps S3 to S5, and is, for example, Δt = 1.02 μsec. After step 5, the process returns to step S3. Step S
4, when the internal time tint reaches the count time tcnt, the operating time count TR is incremented by 1 and the internal time tint is returned to zero (step S
6). By repeating the above steps S3 to S6, the operating time of the printer while the paper is not being fed is recorded in the operating time count TR.

As a result of the determination in step S3, when the paper is to be fed, the process proceeds to step S7. Here, the number of rotation steps of the paper feed motor in the paper feed (hereinafter referred to as the paper feed step number) is added to the paper feed amount count PR, and the time required for the paper feed (uniquely from the number of paper feed steps The value obtained by dividing (determined) by the count time tcnt is added to the operation time count TR. Therefore, the number of paper feed steps is recorded in the paper feed amount count PR, and the operation time of the printer including the time when the paper is not fed and the time when the paper is fed is recorded in the operation time count TR. Become.

Next, in step S8, it is determined whether or not the paper feed amount count PR has reached a predetermined paper feed amount maximum count PRmax. In this embodiment, 2 ¹⁶ is the maximum paper feed amount count value PRmax. If the paper feed amount count PR does not reach the paper feed amount maximum count value PRmax, the process proceeds to step S9, and it is determined whether the operating time count TR reaches the operating time count maximum value TRmax. . In this embodiment, 2 ¹⁶ is the maximum operation time count value TRmax. As described above, tcnt = 6.
Since it is 71 ± 0.2 msec, the operation time count TR reaches the maximum value TRmax in about 7.3 minutes. In this embodiment, the 7.3 minutes is a value determined from the heat generation characteristic of the paper feed motor and has the following meaning. That is, 7.
If the number of paper feed steps performed in 3 minutes exceeds 2 ¹⁶ steps, heat generation problem of the paper feed motor may occur. If it does not exceed 2 ¹⁶ steps, heat generation problem occurs. Absent. Therefore, if the number of paper feeding steps performed in 7.3 minutes is controlled so as not to exceed 2 ¹⁶ steps and be as high as possible, the highest throughput can be obtained without generating heat of the motor. .
Under this idea, control is performed as follows.

As a result of the determination in step S9, when the operating time count TR has not reached the operating time count maximum value TRmax, the process returns to step S3 and the above-described processing is repeated. On the other hand, when the operating time count TR reaches the operating time count maximum value TRmax, the number of paper feed steps is still 2 ¹⁶ when the operating time of 7.3 minutes has elapsed.
Means that it has not reached. In this case, since the problem of motor heat generation does not occur, the paper feed motor may be driven with a heavier duty. Therefore, step S10
And the waiting time tw between paper feeds is the minimum value 20.
If it is 20 msec or more, it is judged whether it is msec or more.
In step S11, a predetermined increase / decrease amount Δtw is subtracted from the waiting time tw, and the operation time count TR and the paper feed amount count PR are reset to zero. Here, Δtw is, for example, 50 ± 0.2 msec. If the waiting time tw has reached the minimum value of 20 ms in step S10, the waiting time tw is maintained at 20 ms,
Then, the operation time count TR and the paper feed amount count PR are reset to zero (step S12). In this way, when the number of paper feeding steps in 7.3 minutes is 2 ¹⁶ or less, the waiting time tw is shortened, and then step S3
Return to.

If the paper feed amount count PR reaches its maximum value PRmax as a result of the judgment in step S8, it means that the paper feed step count reaches 2 ¹⁶ before the operation time of 7.3 minutes has elapsed. It means that you have done it. In this case, it is necessary to reduce the duty because the problem of motor heat generation may occur. Therefore, go to step S13,
The waiting time tw is increased by adding the increase / decrease amount Δtw to the waiting time tw. Further, the quotient obtained by dividing the current operating time count TR by the optimum count ratio tavg is subtracted from the maximum paper feed amount count value PRmax, and the value is set as the paper feed amount count PR. Here, the optimum count ratio tavg is the minimum drive cycle per step allowed for heat generation of the paper feed motor, which is 1 of the paper feed amount count PR.
It is indicated by the count number of the operation time count TR corresponding to the count (one step of the number of paper feeding steps), and tavg = 1 in this embodiment. That is, in this embodiment, when one count of the paper feed amount count PR corresponds to one count of the operation time count TR, in other words,
2 ¹⁶ when step of paper feeding is performed in 7.3 minutes, and the heat generation limit duty during prolonged heavy-duty drive it. The quotient obtained by dividing the current operation time count TR by the optimum count ratio tavg means the number of paper feed steps allowed by the heat generation limit duty, and the value obtained by subtracting this from the paper feed amount count maximum value PRmax. ,
This means the number of steps in which the number of paper feed steps actually executed exceeds the number of steps at the above-mentioned limit duty. In step S13, this excess step number is set in the paper feed amount count PR. Further, the operating time count TR is reset to zero. In this way, when the number of paper feed steps reaches 2 ¹⁶ before the operating time reaches 7.3 minutes, the waiting time tw between paper feeds is extended and exceeded in order to reduce the duty. Then, the number of paper feed steps executed is set in the paper feed amount count PR, and the control returns to step S3.

By repeating the above process, the waiting time tw is adjusted so that the waiting time tw is extended if the duty is too heavy, and the waiting time tw is shortened if the duty is too light. The average number of paper feed steps for 7.3 minutes during heavy duty drive is set to converge to 2 ¹⁶ steps or less.

FIG. 2 shows a modification of the processing flow of FIG. The difference of the processing flow of FIG. 2 from FIG. 1 lies in step S
This is the point where the control proceeds to step S9 after 5 or S6.
That is, the operating time count TR is checked even when the paper is not fed, and if it reaches the maximum value TRmax, the waiting time tw is shortened and the duty is increased.

By the way, in the above embodiment, the control is entirely performed by the programmed computer, but it is also possible to realize a part or all of it by only hardware. For example, the counters TR and PR may be realized by using a hardware counter circuit.

[0018]

As described above, according to the present invention,
By monitoring the printer operation time and the pulse motor drive amount performed during that period, the waiting time for intermittent drive of the pulse motor is increased or decreased so that the relationship between the two becomes less than the heat generation limit duty during long-term heavy duty drive. Therefore, the prevention of heat generation of the pulse motor and the maintenance of high throughput can both be achieved.

[Brief description of drawings]

FIG. 1 is a flowchart showing a process of a microcomputer in an embodiment of a paper feed control device according to the present invention.

FIG. 2 is a flowchart showing a modification of the processing flow of FIG.

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Claims (3)

[Claims] 1. A device for controlling a pulse motor used in a printer, comprising means for measuring an operating time of the printer, and means for measuring a drive amount of the pulse motor executed during the operating time. A means for increasing or decreasing the waiting time for the intermittent driving of the pulse motor so that the numerical relationship between the measurement value of the operating time and the measurement value of the driving amount satisfies a predetermined constant condition. Paper feed control device. 2. The apparatus according to claim 1, wherein the waiting time increasing / decreasing means is configured to, when the drive amount measurement value reaches a predetermined fixed amount before the operating time measurement value reaches a predetermined constant time, A paper feed control device characterized by increasing the waiting time and decreasing the waiting time when the operating time measurement value reaches the predetermined time before the drive amount measurement value reaches the predetermined amount. 3. The apparatus according to claim 2, wherein the actuation time measuring means resets the actuation time measurement value to zero when the actuation time measurement value reaches the predetermined time and measures the subsequent actuation time. Repeatedly, the drive amount measuring means,
When the drive amount measurement value reaches the predetermined amount, the drive amount measurement value is reset to an excess amount of drive and the subsequent measurement of the drive amount is repeated.