JPH02220561A - Facsimile equipment - Google Patents

Abstract

PURPOSE:To decrease the temperature rise of a motor and a drive circuit by decreasing a drive current at the rotation more than that at the rotation stop of a stepping motor driven intermittently. CONSTITUTION:A device control section 9 has a drive circuit 17, the circuit 17 supplies a drive current to a stepping motor 16 according to a command from a system control section 8 to drive or stop the motor 16 with the constant current drive method as a rule. Thus, the drive current supplied to the motor 16 is controlled small at the stop of the drive of the motor 16, Thus, while the motor 16 is stopped for a long time, a small drive current flows to reduce the power consumption at the drive stop. As a result, the power consumption of the facsimile equipment is reduced and the temperature rise in the motor 16, the circuit 17 and the power supply is suppressed lower.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a facsimile machine, and particularly to a facsimile machine that uses a stepping motor as a drive source for conveying recording paper.

(Prior Art) Recently, many devices use stepping motors as drive sources for precision control.

For example, in a facsimile machine, a stepping motor drives a recording paper conveyance mechanism to improve recording paper feeding accuracy, thereby improving recording accuracy.

(Problems to be Solved by the Invention) In a facsimile machine, it is necessary to intermittently drive a recording paper conveyance mechanism in accordance with the reception status of image data.

Therefore, the stepping motor also needs to be driven intermittently, but in conventional facsimile machines, the same amount of drive current was applied not only when the stepping motor was rotating, but also when it was stopped, and the stopped position was maintained. However, there was a problem in that the temperature of the stepping motor and the drive circuit increased, and the power consumption increased.

In particular, the temperature of the stepping motor and drive circuit increases more when the stepping motor is stopped than when it is rotating, which is an important problem for facsimile machines that frequently operate intermittently.

Furthermore, in a facsimile machine that is equipped with two rolls of recording paper and is used by switching between them as necessary, the load on the mechanical system varies greatly depending on its operating conditions. That is, when switching between rolls of recording paper, the stepping motor is reversely rotated to rewind one roll of recording paper, and then the stepping motor is rotated forward to feed the other roll of recording paper to the platen roller. The recording head is in contact with this platen roller, and during printing, a roll of recording paper is fed between the platen roller and the recording head, but when switching, the roll of recording paper is fed between the platen roller and the recording head. There is a state where there is no. When the platen roller and recording head come into direct contact, the load is larger than when there is a roll of recording paper between them, and the load torque applied to the stepping motor that drives the platen roller is also large (for example, when printing When the load torque is 700gfcm,
When switching between rolls of recording paper, a load torque of 1200 gfca+ is applied.

Conventionally, two types of countermeasures have been taken for facsimile machines such as those mentioned above. One of them is always 1200gfc
- This is a method that uses a stepping motor that generates more than 1000 torque. However, with this method, there were problems in that the stepping motor became larger, the facsimile machine became larger and more expensive, and a large drive current constantly flowed, increasing power consumption and increasing the temperature of the monitor and drive circuit. . Furthermore, as shown in FIG. 7(a), the recording paper is repeatedly conveyed and stopped, but as shown in FIG. 7(b)
As shown in Figure 7, if the torque of the stepping motor is too large relative to the load of the mechanical system, the positional fluctuation of the recording paper when stopped will be larger than when the torque is small (Figure 7 (C)).
There was a problem that print quality deteriorated.

Another method is to generate a torque of 1200 gfcm or more only during switching, and to generate a torque of 700 gfcm or more during printing. Conventionally, this method has been adopted in Japanese Patent Publication No. 63-27248 and Japanese Patent Application Laid-Open No. 62-2
The one described in Publication No. 64149 has been proposed.

Both of the devices described in these publications change the torque by changing the pulse rate of the drive current supplied to the stepping motor.

However, as shown in Fig. 8, in general, the torque of a stepping motor does not change significantly even if the pulse rate is changed slightly, and the
In order to satisfy gfcm, it is necessary to use a stepping motor with a large output torque. As a result, not only will the same problems as the previous method occur, but the motor rotational speed during switching will be reduced, so the time required to switch the roll paper will be longer (and therefore, there is a risk that communication may sometimes be cut off). There is.

(Purpose of the Invention) Therefore, the invention as claimed in claim 1 reduces the power consumption when the rotation of a stepping motor that is driven intermittently is stopped by making the drive current when the rotation is stopped smaller than the drive current when the rotation is stopped. The aim is to reduce the power consumption of facsimile machines and to keep the temperature rise of the motor and drive circuit to a low level.

Further, the invention according to claim 2 provides a smaller, lower-torque stepping motor by making the driving current of the stepping motor larger than the driving current during recording operation, at least when the platen roller and the recording head are in direct contact with each other. Enables the use of motors to make facsimile machines smaller and
The purpose is to reduce costs, improve print quality, and prevent communication problems.

(Structure of the Invention) In order to achieve the above object, the invention according to claim 1 includes: a conveyance mechanism that conveys recording paper to a recording section; a stepping motor that drives the conveyance mechanism;
a facsimile machine that transports recording paper by intermittently driving a stepping motor in accordance with the reception status of image data during reception, further comprising current control means for controlling the magnitude of a drive current supplied to the stepping motor; The invention according to claim 2 is characterized in that the current control means controls the driving current when the stepping motor stops rotating to be smaller than the driving current when the stepping motor rotates. a recording head that contacts the platen roller and records an image on a roll of recording paper fed between the platen roller; and a second recording head that conveys one of the two rolls of recording paper between the platen roller and the recording head. 1 Fti feeding means;
A second wL feeding means transports the other of the two rolls of recording paper between the platen roller and the recording head; A facsimile machine comprising: a stepping motor that transports recording paper in a forward direction from each transporting means to a platen roller, and a stepping motor that transports recording paper in a reverse direction from the platen roller to each transporting means; A current control means for controlling the magnitude of the current is provided, and the current control means makes the drive current at least when the platen roller and the recording head are in direct contact larger than the drive current during the recording operation. That is.

Hereinafter, a detailed description will be given based on examples.

1 to 4 are diagrams showing an embodiment of the invention according to claim 1. FIG.

FIG. 1 is a block diagram of a facsimile device 1, which includes a scanner 2, a buffer memory 3, a data compression/reproduction section 4, a transmission control section 5, a modem 6, a network control section 7, a system control section 8, and a mechanism. It includes a control section 9, a plotter 10, an operation section 11, and the like.

When transmitting, the facsimile machine 1 scans the document 12 into the scanner 2.
The image information is read by scanning, converted into an electrical signal, and stored in the buffer memory 3. The image data once stored in the buffer 7 memory 3 is reduced in data amount (data compression) in the data compression/reproduction unit 4 without losing the original information.
The signal is sent to the modem 6 via the transmission control section 5 and modulated.

The image data modulated by the modem 6 is sent to the line via the network control section 7. On the other hand, during reception, the modulated signal (image data) manually input from the line is led to the modem 6 via the network control unit 7, demodulated by the modem 6, and then transmitted to the transmission control unit 5 for data compression/reproduction. The data is sent to the data compression/reproduction section 4, where it is reproduced into original information and stored in the buffer memory 3. The image data stored in the buffer memory 3 is sent to the profiler IO and recorded on the recording paper 13. Recording paper 1
3 is controlled by a mechanism control section 9, which controls the drive of the plotter 10 and the scanner 2 according to instructions from the system control section 8.

The system control unit 8 is a ROM that stores the basic program of the facsimile machine and the motor control program of the present invention.
(Read Only Memory) and RAM (Randoa+Acce) where work areas are formed.
ss Memory), etc., and controls each part of the facsimile machine 1 according to the program in the ROM to execute the sequence as the facsimile machine 1, and also executes the motor control process of the present invention.

The operation section 11 is an interface section with an operator, and the network control section 7 is a so-called AA-NCU. A line is connected to the network control section 7, and a telephone 14 is also connected thereto.

As shown in FIG. 2, the printer 10 is equipped with a conveyance mechanism 15 for conveying the recording paper 13 to the recording section, a stepping motor 16 for driving the conveyance mechanism 15, and the like. , a feed roller, a pressure roller that contacts and follows the feed roller, a paper guide that guides the recording paper 13 to the recording section, a platen roller, and the like. The recording section includes a platen roller and a thermal head that comes into contact with the platen roller. The thermal head generates heat and records an image on a recording paper 13 that is fed between it and the platen roller.

The mechanism control section 9 has a drive circuit 17, and the drive circuit 1
7 controls the driving of the stepping motor 16 according to instructions from the system 1 and the control section 8; That is, drive circuit 1
7 supplies a driving current to the stepping motor 16 according to instructions from the system control unit 8, and the stepping motor 1
6 is basically rotated and stopped by a constant current drive method, and when the stepping motor 16 stops rotating, the magnitude of the drive current supplied to the stepping motor 16 is controlled to be small. Therefore, the drive circuit 17 constitutes a current control means.

Next, the invention according to claim 1 is characterized in that the drive current when the stepping motor 16 stops rotating is controlled to be smaller than the drive current when the stepping motor 16 rotates. This motor control process will be explained below based on the flowchart of FIG. 3.

At the time of reception, the facsimile machine 1 reproduces the image data received from the line in the data compression/reproduction section 4, temporarily stores it in the buffer memory 3, and then transfers it to the plotter 10 and prints it on recording paper 13 using the plotter IO. Record.

At the time of this reception, the drive circuit 17 drives the stepping motor 16 according to the transfer state of the image data from the buffer memory 3.
drive the rotation. First, in the initial state, the drive circuit 17 stops the rotation of the stepping motor 16, but instead of not passing a drive current, it supplies a drive current to maintain a predetermined stop position. However, the drive current in this case is less than the drive current C which has a smaller current value than that during rotation (referred to as a small drive current), and the motor holding state is maintained by this small drive current (step Sl). System system'＜B
The unit 8 checks whether there is image data in the buffer memory 3 (step S2), and if there is image data, the driving circuit 17 rotates the stepping motor 16 in accordance with the transfer state of this image data. The drive type current is a drive current with a larger current value than the drive current when rotation is stopped (hereinafter referred to as large drive current). In step S3, the plotter 10 records an image while generally feeding the recording paper 13 by rotating the stepping motor 16.
), the stepping motor 16 is stopped after recording. The system control unit 8 checks the status of the image data in the buffer memory 3.
When there is no more image data, a check is made to see if the end of the document is reached based on whether a facsimile control signal indicating the end of the communication document has been input (step S4). At the end of the original, a large drive current is applied to the stepping motor 1.
6, and performs normal ejection processing of the recording paper 13, that is, ejection processing of the recording paper 13 to the outside of the facsimile apparatus 1 (step S).

In step S, if the document is not at the end, it is determined that the transmission of the image data is delayed for some reason, and no image data is present in the buffer memory 3 for a predetermined period of time, for example, 8 m5e (or more). Please check it out (Step S6).

Step Sz, S<
S6) After a predetermined period of time has elapsed, the drive current is switched to a small drive current and waits for image data to enter the buffer memory 3 (step S).

That is, as shown in FIG. 4, image data is transferred line by line to the buffer memory 3, but when the image data is transferred to the buffer memory 3, the system control unit 8 sends a large amount of information to the mechanism control unit 9. The drive circuit 17 instructs the stepping motor 16 to rotate with the drive current, and the drive circuit 17 sends a large drive current to the stepping motor 16 to record while conveying the recording paper 13. When one line is recorded, the stepping motor 1
The rotational drive of 6 is stopped and a holding state is achieved with a large drive current.

However, the transfer of image data to buffer memory 3 is
If there is no current for m5ec, the drive current for stopping the stepping motor 16 is switched to a small drive current with a small current value, and the stepper motor 16 waits. When image data enters the buffer memory 3 again, the stepping motor 16 is rotated by a large drive current.

Therefore, when the stepping motor 16 is stopped for a long time, a small drive current Uj can be passed instead of the same large drive current as when rotating, as in the conventional case, and the electric power when the stepping motor 16 is stopped is reduced. Consumption can be reduced.

As a result, the power consumption of the facsimile machine 1 can be reduced, and the stepping motor 16 and drive circuit 1
7.Furthermore, the temperature rise of the power supply can be suppressed to a low level.

In addition, after the stepping motor 16 is rotated with a large drive current, it is not immediately switched to a small drive current, and the holding state is maintained at a large drive current for a predetermined period of time, so that paper can be fed smoothly during continuous recording. .

FIG. 5.6 is a diagram showing an embodiment of the invention according to claim 2.

FIG. 5 is a side view of the main part of the facsimile machine 21 that accommodates two rolls of recording paper.

In FIG. 5, the facsimile machine 21 stores two rolls of recording paper 22 and 23.
2 is conveyed toward the platen roller 26 by a feed roller 24 and a pressure roller 25, and the rolled recording paper 23
is conveyed via a turn roller 27 toward a platen roller 26 by a feed roller 28 and a pressure roller 29 . A thermal head (recording head) 30 is in contact with the platen roller 26, and the thermal head yF30 is urged toward the platen roller 26 by an unillustrated urging means. The thermal head 30 has a thermal element, and the rolled recording paper 22 or the rolled recording paper 2 supplied between the platen roller 26 and the platen roller 26 due to the heat generated by the thermal element.
Record the image in step 3.

The facsimile machine 21 has a bronch construction similar to that shown in FIG. 1, except that the mechanism control section 9 stores two rolls of recording paper 22 and 23 as shown in FIG.

Furthermore, the configuration of the system control section 8 is different in order to switch the conveyance of the rolled recording paper 22 and the rolled recording paper 23 and to perform the motor control processing of the invention in the present claims. Furthermore, feed roller 24, feed roller 28
The platen roller 26 is driven by a stepping motor similar to the Stella Pink-F-116 shown in Figure i2, and the stepping motor is driven by a drive circuit similar to the drive J circuit 17 in Figure 2, in principle using the ζ constant current drive method. is driven by. Therefore, the feed roller 24, paper guides 31, 32, pressure roller 25, etc.
2 in the direction of the platen roller 26. The turn roller 27, the feed roller 28
, the pressure roller 29 and the paper guides 32 and 34 constitute a second i1 feeding means 35 that conveys the rolled recording paper 23 toward the platen roller 26.

Next, the effect will be explained.

The present invention is applicable when there is no recording paper between the platen roller 26 and the thermal head 3o and the platen roller 26 and the thermal head 30 come into direct contact with each other due to switching between two rolls of paper, resulting in a large mechanical load. Its feature is that the drive current supplied to the stepping motor is made larger than the drive power supplied during recording. This motor control process will be explained below.

In the facsimile machine 21 shown in FIG. 5, normally one of the rolled recording paper 22 and the rolled recording paper 23 is supplied between the platen roller 26 and the thermal head 3o. Suppose that the signal is supplied as shown in FIG. , when recording in the second state, the facsimile machine I drives the feed roller 24 and the platen roller 26 with a stepping motor to convey the rolled recording paper 22 in the forward direction from the feed roller 24 toward the platen roller 26. Thermal head 3
Recording is performed using o. During this recording, etc., the platen roller 2
When the rolled recording paper 22 or the rolled recording paper 23 is present between the thermal terminal 6 and the thermal outlet 30, the mechanical load on the stepping motor of the facsimile machine 21 is approximately 700 gfcm, and at this time, the load torque of the stepping motor is approximately 700 gfcm. If the torque of the stepping motor becomes too large, as shown in FIG. 7, the amount of vibration of the recording paper increases (and the recording quality deteriorates. In the facsimile machine 21, a driving current is supplied whose stepping motor torque slightly exceeds about 700 gfcm during recording.

Now, the stepping motor has a current as shown in Figure 6.
If it has torque characteristics, it will supply a drive current of about 240 mA.

On the other hand, the facsimile machine 21 needs to switch from one recording paper to another due to the recording paper being used running out or the document size being different.

In this recording paper switching mode, for example, the roll recording paper 2
2 is rewound to a predetermined position between the platen roller 2G and the feed roller 24, and then the rolled recording paper 23 is conveyed in the forward direction to the platen roller 26 and the thermal head 3.
It is necessary to supply it between 0 and 0. At this time, as described above, a state occurs in which the rolled recording paper 22 or the rolled recording paper 23 is not present between the platen roller 26 and the thermal head 30, and the load torque increases. In this state, the torque required for the stepping motor is 1200 gfc.
m, it can be handled by supplying a drive current of about 400 mA as shown in FIG. Therefore,
In this embodiment, when the switching mode is entered, the drive current supplied from the drive circuit to the stepping motor is switched to a large drive current, and the switched recording paper is supplied between the platen roller 26 and the thermal head 30, and the recording paper is then printed. When the mode is switched, the drive current is switched to the normal recording mode.

However, the frequency of the drive current remains unchanged.

Therefore, it is possible to use a large drive current only when a large torque is required, and a small drive current when only a small torque is required, and it is possible to use a small, low-torque motor. It is possible to reduce power consumption and heat generation.

As a result, the facsimile machine 21 can be made smaller and less expensive, and the power consumption of the facsimile machine 21 can be reduced. Furthermore, since unnecessarily large torque is not generated during recording, recording accuracy can be improved. Furthermore, since a large torque is generated in switching mode, switching speed can be increased.
It is possible to prevent communication troubles from occurring as in the conventional case.

In the above embodiment, a large drive current is applied during the switching mode, but this is not a limitation. Calculated numerically, a large drive current may be caused to flow only when there is no recording paper between the platen roller 26 and the thermal head 30 and the platen roller 26 and the thermal head 30 are in direct contact.

(Effects) According to the invention as set forth in claim 1, since the driving current can be reduced when the stepping motor is stopped, the power consumption when the stepping motor is stopped can be reduced, and the power consumption of the facsimile machine 1 can be reduced. At the same time, the temperature rise of the stepping motor, drive circuit, power supply, etc. can be suppressed to a low level.

According to the second aspect of the invention, at least when the platen roller and the thermal head are in direct contact without using the recording paper, a larger drive current is applied than during recording, and the stepping motor is driven with a smaller drive current during recording. Therefore, it is possible to use a small stepping motor with low l/lux, and also to reduce power consumption and heat generation of the stepping motor. As a result, the facsimile machine can be made smaller and less expensive, and the power consumption of the facsimile machine can be reduced. Furthermore, since unnecessarily large torque is not generated during recording, recording accuracy can be improved. Furthermore, since a large torque is generated in the switching mode, the switching speed can be improved and communication troubles can be prevented.

[Brief explanation of the drawing]

1 to 4 are diagrams showing an embodiment of a facsimile apparatus according to the invention as claimed in claim 1, in which FIG. 1 is a block diagram of the facsimile apparatus, FIG. 2 is a block diagram of its main parts, and FIG. The figure is a flowchart of the motor control process, and FIG. 4 is a diagram showing the relationship between image data and drive current in the motor control process. 5.6 is a diagram showing an embodiment of the facsimile device of the invention as claimed in claim 2, FIG. 5 is a side view of the main part of the facsimile device, and FIG. 6 is a torque-drive current of the stepping motor. It is a characteristic diagram. Figure 7.8 is an explanatory diagram of the operation of a conventional facsimile machine, and Figures 7(a), (b), and (c) are diagrams each showing the conveyance state of recording paper, and Figure 7(a) is a diagram for explaining the operation of a conventional facsimile machine. Figure 7(b) shows the amount of paper movement in relation to time; Figure 7(b) shows the amount of variation in the recording paper at high torque; and Figure 7(C) shows the amount of variation in the recording paper at low torque. The diagram shown in FIG. 8 is a diagram showing the relationship between the torque of the pulse motor and the pulse rate of the drive current. DESCRIPTION OF SYMBOLS 1...Facsimile device, 3...Buffer memory, 9...Mechanism control unit, 10...Block, 13...Recording paper, 15... Conveyance mechanism, 16... Stepping motor, 17...
・Drive circuit, 21...Facsimile device, 22.23...Rolled recording paper, 24.28.
...Feed roller, 26...Platen roller, 30...Thermal head, 33...First feeding means, 35...Second conveyance means.

Claims (2)

[Claims] (1) Includes a transport mechanism that transports the recording paper to the recording section and a stepping motor that drives the transport mechanism, and when receiving,
In a facsimile machine that transports recording paper by intermittently driving a stepping motor in accordance with the reception status of image data, a current control means for controlling the magnitude of a drive current supplied to the stepping motor is provided, and the current control means performs the following steps: A facsimile device characterized in that the drive current when the stepping motor stops rotating is controlled to be smaller than the drive current when the stepping motor rotates. (2) Two rolls of recording paper, a platen roller, a recording head that contacts the platen roller and records an image on the roll of recording paper that is fed between the platen roller, and two rolls of recording paper. a first conveyance means for conveying one of the two rolls of recording paper between the platen roller and the recording head; a second conveyance means for conveying the other of the two rolls of recording paper between the platen roller and the recording head; The reverse rotation drives the platen roller, the first conveyance means, and the second conveyance means to convey the rolled recording paper in the forward direction from each conveyance means to the platen roller, and also in the reverse direction from the platen roller to each conveyance means. A facsimile apparatus is provided with a stepping motor for conveyance, and includes current control means for controlling the magnitude of the drive current supplied to the stepping motor, and the current control means causes at least the platen roller and the recording head to be in direct contact with each other. A facsimile apparatus characterized in that a drive current during a facsimile operation is larger than a drive current during a recording operation.