JPH10145551A - Original reader - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the occurrence of disturbance and loss of synchronism in reading image data by predicting a load state by means of correlation with a present original carrier position and selecting an optimum driving control pattern as against a corresponding re-start operation from a storage table. SOLUTION: A separation roller group 40 separates the original from an original sheaf 31 on an original tray 32 one by one so as to carry it. A contact image sensor 34 reads image data of the original which passes through at prescribed carrier speed by a carrier roller group 50. A paper discharge roller group 60 feed the original where reading is completed to a paper discharge tray 35. The respective roller groups 40, 50 and 60 of separation, carriage and paper discharge are driven by a stepping motor, synchronized with the original carrier position and interlocked. A controller stores the prediction value of the load state in the stepping motor and the driving control pattern being optimum for the re-start operation of the stepping motor in the state.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a document reading apparatus, and more particularly, to a document reading apparatus optimally applied to a facsimile apparatus having an intermittent operation such as a stop and a restart during a document reading operation.

[0002]

2. Description of the Related Art Generally, in a filing apparatus, a facsimile apparatus, or the like for reading, storing, and transmitting image data serving as a document, the image on the document surface is conveyed and moved to a sensor unit fixed at a predetermined position. A sheet transport type document reading device that sequentially reads data is employed.

For example, when such a document reading apparatus is applied to a facsimile apparatus and image data of a document is directly transmitted, the transmission operation is executed after the read image data is temporarily stored in a transmission data memory. When the transmission data memory is in the FULL state, a control method of stopping the original reading operation and giving priority to the transmission operation is adopted.
Therefore, the intermittent drive for stopping and restarting the reading operation of the image data at an intermediate position of the document must be performed, and the document transport system performing such an intermittent drive has high transport control accuracy and is easy to handle. A stepping motor is used as a drive source.

[0004]

An example of a document feeder using a stepping motor as a driving source is disclosed in Japanese Unexamined Patent Publication No. Hei.
As described in Japanese Patent Application Laid-Open No. 142395, by switching the supply current value to the stepping motor in response to a load change caused by normal document conveyance and executing slow-up control, smooth and efficient driving is achieved. It can be performed.

However, as described above, in the facsimile apparatus, intermittent driving in which the reading operation of the image data of the original is stopped and restarted at an intermediate position inevitably occurs, so that the conveyance as described in JP-A-2-142395 is required. When a document reading device of the document type is applied, in addition to the load fluctuation accompanying the normal document conveyance, the motor load fluctuates due to the intermittent operation. There was a problem that tone occurred.

According to the present invention, a drive control according to a load variation on a stepping motor is performed for an intermittent operation such as stop and restart that occurs during a document reading operation,
It is an object of the present invention to provide a document reading apparatus capable of preventing the occurrence of disturbance of read image data and step-out.

[0007]

According to the first aspect of the present invention,
In a sheet-conveying type document reading device that conveys a document having image data by rollers driven by a stepping motor and sequentially reads the image data, a pulse number counting unit that counts the number of driving pulses supplied to the stepping motor; Pattern storage means for storing a plurality of drive control patterns for controlling the driving state of the stepping motor corresponding to the load state of the stepping motor for each of the document transport positions; and the document when reading image data of the document. Load determining means for determining the load state of the stepping motor at the stop position of the document in accordance with the number of pulses counted by the pulse number counting means in response to the stop and restart of the conveyance, and stored in the pattern storing means. From the plurality of drive control patterns thus determined by the load determining means. Pattern selection means for selecting a drive control pattern corresponding to the load state of the stepping motor, and drive control means for controlling the drive state of the stepping motor in accordance with the drive control pattern selected by the pattern selection means. It is characterized by having.

[0008] According to the document reading apparatus having such a configuration,
During intermittent operation involving stop and restart of image data reading operation, it is possible to accurately grasp the load fluctuation of the stepping motor and select the optimal drive control pattern corresponding to the load state. Even in the case of a large document conveying path or intermittent operation during high-speed reading of image data, disturbance of read image data and occurrence of step-out can be prevented.

According to a second aspect of the present invention, in the original reading apparatus according to the first aspect, the drive control pattern of the stepping motor stored in the pattern storage means is a slow-up control pattern. I have. According to the document reading apparatus having such a configuration, at the time of the intermittent operation accompanied by the stop and restart of the image data reading operation, the load state of the stepping motor at the time of restarting the reading operation is accurately grasped, and the load state is reduced. Since it is possible to select a slow-up control pattern for executing the optimum start-up control in accordance therewith, it is possible to prevent the read image data from being disturbed or stepping out due to the intermittent operation.

[0010] Further, the invention according to claim 3 is based on claim 1.
In the above document reading apparatus, the drive control pattern of the stepping motor stored in the pattern storage means is a slowdown control pattern. According to the document reading apparatus having such a configuration, at the time of the intermittent operation involving the stop and restart of the reading operation of the image data, the load state of the stepping motor at the time of the stop of the reading operation is accurately grasped, and according to the load state. Thus, it is possible to select a slowdown control pattern for executing the optimal fall control, and thus it is possible to prevent the read image data from being disturbed or stepping out due to the intermittent operation.

The invention described in claim 4 is the first invention.
In the above-described original reading apparatus, the drive control pattern of the stepping motor stored in the pattern storage unit is a slow-up control pattern and a slow-down control pattern. According to the document reading apparatus having such a configuration, when the reading operation of the image data is stopped and the intermittent operation accompanied by the restart is performed, the reading operation is stopped and the load state of the stepping motor at the time of the restart is accurately grasped. Since it is possible to select a slow-up control pattern and a slow-down control pattern for executing optimal startup and shutdown control of the stepping motor corresponding to the state, it is possible to prevent disturbance or loss of read image data due to intermittent operation. be able to.

The invention described in claim 5 is the first invention.
In the above document reading apparatus, the drive control pattern of the stepping motor stored in the pattern storage means is a phase excitation pattern. According to the document reading apparatus having such a configuration, in the case of the intermittent operation involving the stop and restart of the reading operation of the image data, the load state of the stepping motor when the reading operation is stopped is accurately grasped, and the load state is responded to. Since it is possible to select a phase excitation pattern that generates an optimal braking force, it is possible to prevent disturbance of read image data and step-out due to intermittent operation.

The invention described in claim 6 is the first invention.
In the document reading apparatus described above, the drive control patterns of the stepping motor stored in the pattern storage means are a slowdown control pattern and a phase excitation pattern. According to the document reading apparatus having such a configuration, in the case of the intermittent operation involving the stop and restart of the reading operation of the image data, the load state of the stepping motor when the reading operation is stopped is accurately grasped, and the load state is responded to. Since it is possible to select the slowdown control pattern and the phase excitation pattern for performing the optimal fall control and the optimal braking control to be performed, it is possible to prevent disturbance of read image data and step-out due to the intermittent operation.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, the basic concept of drive control of a stepping motor in a document reading apparatus according to the present invention will be described with reference to the block diagram of FIG.
As shown in FIG. 1, a control signal to a motor driver (drive control means) 2 which outputs a predetermined pulse signal to the stepping motor 1 and controls the drive is a CP in the controller 10.
U20, in particular, counts the number of pulses of a signal supplied to the stepping motor 1 in the CPU 20 to detect a document transport position associated with an intermittent operation such as stopping and restarting the stepping motor 1 during document transport. And a plurality of drive control patterns (for example, a slow-up table) related to start-up and shutdown control at the time of stop and restart accompanying intermittent operation according to the load state of the stepping motor. , A drive control pattern storage unit (pattern storage means) 24 storing a slow down table or a phase excitation method, and a pulse number counting unit to determine the load state of the stepping motor from the document transport position detected and output. A load state determination unit (load determination means) 22 which performs the determination based on the determined load state. It is configured to include a drive control pattern selecting unit for the raising and the drive control pattern for executing falling control to select from the drive control pattern storage unit of optimal and (pattern selection section) 23.

Next, a specific example of a correlation table between the original transport position and the load state of the stepping motor referred to by the load state determining means of the present invention will be described in the case where the original reading apparatus of the present invention is applied to a general facsimile apparatus. Will be described as an example. Note that, for the sake of simplicity, the roller configuration and the like are simplified. 2, a document reading unit 100 includes a document tray 32 on which a document bundle 31 including a plurality of documents is placed, and a document bundle 3 on the document tray 32.
A separation roller group 40 that separates originals one by one and transports them toward an image data reading unit, and an image data reading unit that reads image data of the original, for example, a contact image sensor (CIS) 34 on a predetermined position. Roller group 50 for passing at a transport speed of
And a paper discharge roller group 60 that discharges the document whose image data has been read onto the paper discharge tray 35. Here, each roller group 4 for separation, conveyance, and paper discharge
Reference numerals 0, 50, and 60 are connected via a drive system such as a gear mechanism so that the same stepping motor or a stepping motor provided for each roller group synchronizes the transfer speed of the entire document transfer unit. A registration sensor 33 for detecting the leading edge and the trailing edge of the document to be transported is provided between the transport roller group 50 and the CIS 34.
The start and end timings of reading image data in IS34 are detected. The CIS 34 includes a scanning light source that irradiates scanning light line by line to image data on the surface of the document, a lens that converges the scanning reflected light, a mirror that guides the converging light to a predetermined path, and a convergent light that is guided by the lens and the mirror. It is composed of a CCD sensor for reading and detecting. The document conveyed on the CIS 34 is pressed and adhered to the image data reading surface by the conveyance roller group 50 and the paper ejection roller group 60.

In the document reading section 100 of the facsimile apparatus having such a configuration, when a predetermined drive pulse signal is output from the motor driver 2 to the stepping motor 1 in accordance with an instruction from the controller 10, the separation roller group 40
The pickup roller 40a rotates in the counterclockwise direction to feed the uppermost document from the document bundle 31, and the feed roller 40b and the reverse roller 40c rotate in the counterclockwise direction to feed the uppermost document. Only the upper document is separated and transported. Next, the separated document is sandwiched between a pull-out roller 50a that rotates clockwise and a pull-out pressure roller 50b that rotates while being pressed by the roller, and is conveyed toward the CIS.
When the leading edge of the document is detected by the registration sensor 33, a signal to start the reading operation is output from the controller 10 to the CIS 34, and the document is conveyed on the CIS 34 at a predetermined reading conveyance speed, and the image data of the document is read. Are read line by line. The leading end of the document that has passed through the CIS 34 reaches a paper discharge roller group 60, and is sandwiched between a paper discharge roller 60a that rotates clockwise and a paper discharge pressure roller 60b that is pressurized and rotates together with the paper discharge roller 60a. And the rear end of the document is sequentially passed through the separation roller group 40 and the conveyance roller group 50,
When detected by the registration sensor 33, a signal to end the reading operation is output from the controller 10 to the CIS 34, and the document from which all the image data has been read is finally discharged to the discharge tray 35 by the discharge roller group 60. .

An example of the correlation between the document transport position (time) in the document reading section and the load state of the stepping motor will be described with reference to FIG. Note that the correlation shown here is different depending on the roller configuration of the document reading unit, the document transport path, the separation method, etc. Actually, an individual load state for each document transport position is extracted, and the type of load variation is determined. To set.

In FIG. 3, the document transport position and the load state will be described with reference to the document reading section 100 and Table 1 shown in FIG. 2. A to M in FIG. Yes, ~ represent the load state of the motor. Here, as the document transport position, the transport roller group 50 that most affects the reading operation of the image data of the document is used.
And the position of the discharge roller group 60 will be described.

Specifically, as shown in Table 1, when the original is not conveyed, the stepping motor receives only basic loads such as the rotational resistance of each roller group and the contact resistance of the drive system gears. It is in an applied, so-called no-load state. Subsequently, when the original is transported in the order of the separation roller group 40, the transport roller group 50, and the discharge roller group 60, the motor load is reduced at the time (A) when the leading end of the first original (1) reaches the transport roller group 50. The load is increased, and the motor load is further increased at the time (B) when the leading edge of the first document (1) passes through the CIS 34 and reaches the sheet discharge roller group 60 (B), and enters the load state. Subsequently, at the time (C) when the rear end of the first document (1) passes through the transport roller group 50, the motor load becomes only the paper discharge roller group 60, the load is reduced, and the load state is established. Next, at the time (D) when the leading edge of the second document (2) reaches the transport roller group 50, the motor load increases again and the load state is entered.
As described above, when a plurality of originals are continuously conveyed and image data is read, the loads on the separation roller group 40, the conveyance roller group 50, and the paper discharge roller group 60 are regularly repeated, and the load of the motor is reduced. The state is →→→→ ・ ・ ・
repeat. When the trailing end of the final document (END) passes through the separation roller group 40 (K), the load on the motor is applied only to the conveyance and discharge roller groups 50 and 60, the load is reduced, and the load state is established. Manuscript (EN
D) When the rear end passes through the transport roller group 50 (L),
Further, the load is reduced to a load state, and the sheet returns to a no-load state when the sheet passes through the discharge roller group 60.

The load state discriminating section refers to the correlation table between the document conveying position and the load state of the stepping motor, which is prepared in advance, so that the load state is determined from the document position counted and detected by the pulse number counting section. Is determined.

[0021]

[Table 1]

Further, the drive control pattern storage section stores FIG.
And a slow-up table capable of executing a start-up control of a stepping motor and a slow-down capable of executing a fall-off control, which are optimal for stopping and restarting operations of the stepping motor in each load state known in advance as shown in Table 1. A drive control pattern composed of a table or a phase excitation method capable of executing a braking control alone or a combination thereof is stored, and the drive control pattern selection unit determines the load state of the stepping motor determined by the load state determination unit. And selects the optimal drive control pattern from the drive control pattern storage unit and outputs a control command to the motor driver.

Next, the operation when the original reading apparatus according to claim 2 is applied to a normal facsimile apparatus will be described with reference to FIG.
This will be described with reference to the flowchart shown in FIG. When a command to start transporting and reading a document is output from the controller 10, the motor driver 2 operates the stepping motor 1.
A pulse signal is output to the stepping motor 1 and the document conveying operation is started (S11), and the pulse number counting section 21 in the CPU 20 starts counting the number of driving pulses output to the stepping motor 1 (step S11). S12). The image data of the document is sequentially read by the CIS 34 and temporarily stored in the transmission memory. The document is conveyed and the image data is read out until the transmission memory is in the FULL state. When the capacity of the transmission memory becomes the FULL state or when the predetermined memory capacity is reached (S13), the controller 10 sets the motor to the motor state. Stepper motor 1 for driver 2
Is output (S14). The motor driver 2 stops the output of the drive pulse signal based on the stop command from the controller 10, and stops the reading operation of the document at the predetermined transport position (S15). At this time, the facsimile communication unit (not shown) transmits the image data stored in the transmission memory to a predetermined destination. When the transmission of the image data is completed, the capacity of the transmission memory becomes EMPTY
When the state or the predetermined free space is reached, the CPU 2
The load state determination unit 22 within 0 obtains the document position information from the pulse number counting unit 21, and determines the load state of the stepping motor 1 with reference to the above-described load state correlation table (S16). Next, the drive control pattern selection unit 23
An optimal control pattern corresponding to the load state determined by the load state determination unit 22 is selected from the drive control pattern storage unit 24 (S17). Here, a plurality of types of slow-up control patterns related to the start-up control of the stepping motor 1 are stored in the drive control pattern storage unit 24,
As a specific example, the shape and inclination of the slow-up curve represented by the time from the stop state to the predetermined rotation frequency or the stationary time are set variously so that the document does not run idle for each load state of the stepping motor 1. The stored throw-up table is stored. Therefore, by referring to the slow-up table in the drive control pattern storage unit 24 based on the load state of the stepping motor 1 determined by the load state determination unit 22, an optimal slow-up control pattern that does not cause the document to run idle is uniquely determined. The drive control pattern selection unit 23 selects a predetermined slow-up control pattern as the start-up control when the stepping motor 1 is stopped, and the controller 10 controls the motor driver 2 based on the selected control pattern. A command is issued to execute a restart operation (S18). Motor driver 2
Increases the drive pulse signal based on the slow-up control pattern commanded by the controller, and restarts the original reading operation from a predetermined transport position (S19).

Thus, in the document reading apparatus according to the second aspect, the load state of the stepping motor 1 at the time of restart after the reading operation is stopped is accurately grasped by the load state determining section 22 with reference to the correlation table. The drive control pattern selection unit 23 selects a control pattern capable of executing the optimum start-up control corresponding to the load state determined from the plurality of slow-up control patterns stored in the drive control pattern storage unit 24. Therefore, the idle running of the document accompanying the restart operation of the document reading operation stopped halfway can be suppressed.

Next, the operation when the original reading apparatus according to the third, fifth or sixth aspect is applied to a normal facsimile apparatus will be described with reference to the flowchart shown in FIG. When a command to start a document conveyance and reading operation is output from the controller 10, the motor driver 2 outputs a predetermined pulse signal to the stepping motor 1 to start the document conveyance operation (S21). Starts counting the number of drive pulses output to the stepping motor 1 (S22). The image data of the document is sequentially read by the CIS 34 and temporarily stored in the transmission memory. The document is conveyed and the image data is read until the transmission memory is in the FULL state. When the capacity of the transmission memory becomes the FULL state or when the predetermined memory capacity is reached (S23),
The load state discriminating unit 22 in the CPU 20 is a pulse number counting unit 2
1, the load state of the stepping motor 1 is determined by referring to the load state correlation table described above (S24). Next, the drive control pattern selection unit 2
3 stores the optimum control pattern corresponding to the load state determined by the load state determination unit 22 in the drive control pattern storage unit 2.
4 (S25). Here, the drive control pattern storage unit 24 stores a slowdown control pattern or a phase excitation pattern related to the fall control of the stepping motor 1,
Alternatively, a plurality of types of combinations of the slowdown control pattern and the phase excitation pattern are stored. As a specific example of the slowdown control pattern, a stepping motor 1
A slow-down table in which the shape and inclination of a slow-down curve represented by a time from a predetermined rotation frequency to a stop and a slope or a stationary time are set so that the document does not run idle for each load state is stored. . Further, as a specific example of the phase excitation pattern, in a state where the load of the stepping motor 1 is small, for example, in a load state of the load variation points K to M in FIG. Since idling is likely to occur, the stepping motor 1 is subjected to a stop control in which a strong braking force (brake) is applied by employing an excitation pattern in a single phase, and the stepping motor 1 has a large load, for example, as shown in FIGS. The load states of the load change points A to K in Table 1,
In the case of (1), since the braking component due to the load is large and the document is unlikely to run idle, the stop control in which the stepping motor 1 has a weak braking force (brake) by using an excitation pattern of a plurality of phases is performed. The phase excitation table set as described above is stored. Therefore, if the slowdown table and / or the phase excitation table of the drive control pattern storage unit 24 or both tables are referred to from the load state of the stepping motor 1 determined by the load state determination unit 22, the optimal running that does not cause the idle running of the document is obtained. The control pattern for executing the fall control is uniquely determined, and this control pattern is selected by the drive control pattern selection unit 23, and the controller 10 is based on the control pattern selected for the motor driver 2. A command is issued to execute a stop operation (S26). The motor driver 2 reduces the drive pulse signal based on the control pattern commanded by the controller 10, or stops the reading operation of the document at a predetermined transport position by a predetermined braking force (S2).
7). At this time, the facsimile communication unit (not shown) transmits the image data stored in the transmission memory to a predetermined destination. When the transmission of the image data is completed and the capacity of the transmission memory becomes the EMPTY state or a predetermined free space, the controller 10 instructs the motor driver 2 to execute a restart operation (S28). The motor driver 2 outputs a drive pulse signal based on a restart command from the controller 10, and restarts the original reading operation from a predetermined transport position (S29).

As described above, the load state discriminating section 22 accurately grasps the load state of the stepping motor 1 when the reading operation is stopped by referring to the correlation table. Selector 23
6. A control pattern capable of executing optimum start-up control corresponding to the determined load condition from a plurality of slow-up control patterns stored in the drive control pattern storage unit 24. 7. The original reading apparatus according to claim 6, wherein a control pattern capable of executing an optimal start-up control is selected from a plurality of phase excitation patterns stored in the drive control pattern storage unit. In, since a control pattern capable of executing an optimal start-up control can be selected from a combination of a plurality of slow-up control patterns and phase excitation patterns stored in the drive control pattern storage unit 24, It is possible to suppress the idle running of the document due to the stop operation at the middle position of the reading operation.

Next, the operation when the original reading apparatus according to claim 4 is applied to a normal facsimile apparatus will be described with reference to FIG.
This will be described with reference to the flowchart shown in FIG. When a command to start transporting and reading a document is output from the controller 10, the motor driver 2 operates the stepping motor 1.
, A predetermined pulse signal is output, and when the document conveying operation is started (S31), the pulse number counting section 21 in the CPU 20 starts counting the number of driving pulses output to the stepping motor 1 ( S32). The image data of the document is sequentially read by the CIS 34 and temporarily stored in the transmission memory. The document is conveyed and the image data is read until the transmission memory is in the FULL state. When the capacity of the transmission memory becomes the FULL state or the predetermined memory capacity (S33), the load in the CPU 20 is reduced. The state determination unit 22 obtains the document position information from the pulse number counting unit 21 and determines the load state of the stepping motor 1 with reference to the above-described load state correlation table (S3).
4). Next, the drive control pattern selection unit 23 selects an optimal control pattern corresponding to the load state determined by the load state determination unit 22 from the drive control pattern storage unit 24 (S35). The drive control pattern storage unit 24 stores a plurality of types of slowdown control patterns and slowup control patterns related to the fall control of the stepping motor 1. Specific examples of the slowdown control pattern and the slowup control pattern are the same as those described with reference to FIGS.
By referring to the slowdown table of the drive control pattern storage unit 24 based on the load state of the stepping motor 1 determined by the step 2, the control pattern for executing the optimal fall control that does not cause the document to run idle is uniquely determined, Once selected, the controller 10 instructs the motor driver 2 to execute a stop operation based on the selected control pattern (S36). The motor driver 2 reduces the drive pulse signal based on the control pattern commanded by the controller 10, or stops the reading operation of the document at a predetermined transport position by a predetermined braking force (S3).
7). At this time, the facsimile communication unit (not shown) transmits the image data stored in the transmission memory to a predetermined destination. When the transmission of the image data is completed and the capacity of the transmission memory reaches the EMPTY state or a predetermined free space, the drive control pattern selection unit 23 determines in step S
In step 34, a slow-up control pattern capable of executing the optimal start-up control of the stepping motor 1 without causing the document to run idle in accordance with the load state determined by the load state determination unit 22 is selected from the drive control pattern storage unit 24. (S38). The controller 10 instructs the motor driver 2 to execute a restart operation based on the selected control pattern (S39), and the motor driver 2 issues a drive pulse signal based on the slow-up control pattern instructed by the controller. And the reading operation of the document is restarted from the predetermined transport position (S40).

As described above, in the document reading apparatus according to the fourth aspect, the load state determining section 22 accurately grasps the load state of the stepping motor 1 when the reading operation is stopped and restarted by referring to the correlation table. The drive control pattern selection unit 23 determines from the plurality of slowdown control patterns and the slowup control patterns stored in the drive control pattern storage unit 24 an optimal stand-up and stop operation corresponding to the determined load state. Since it is possible to select a control pattern capable of executing the lowering and starting control, it is possible to suppress the idle running of the document due to the stop and restart operations in the middle of the document reading operation.

In the above-described embodiment, the configuration and operation when the original reading apparatus of the present invention is applied to a facsimile apparatus has been described as an example. However, the present invention is not limited to this. It goes without saying that the present invention can be favorably applied to a device that involves an intermittent operation such as stop and restart during the data reading operation.

[0030]

As described above, according to the first aspect of the present invention, at the time of the intermittent operation involving the stop and restart of the image data reading operation, the document conveying position is detected by the pulse number counting means, and the load state is detected. The discriminating means accurately grasps the load condition of the stepping motor by referring to the correlation table, and selects the optimum drive corresponding to the load condition by the drive control pattern selecting means from the plurality of drive control patterns stored in the drive control storage means. Since the control pattern can be selected, the drive control and the braking control when stopping and restarting the document conveyance can be performed under the load condition even in the case of the intermittent operation during the high speed reading operation of the document conveyance path or image data where the load fluctuation is large. It can be executed in the optimal pattern according to the original, and efficiently prevent the occurrence of disturbance of read image data and step-out due to idle running of the document It can be. Therefore, it is possible to realize a good reading operation without disturbing an image for a device that causes an intermittent operation during reading of a document as in the case of direct transmission of a facsimile apparatus.

According to the second aspect of the present invention, at the time of the intermittent operation accompanied by the stop and restart of the image data reading operation, the load state of the stepping motor at the restart after the stop of the reading operation is determined by the load state determining means. It is possible to accurately grasp by referring to the correlation table and to select a slow-up control pattern for executing the optimal start-up control corresponding to the load state from a plurality of slow-up control patterns stored in the drive control storage means. Therefore, even in the case of intermittent operation with a large load fluctuation, restart operation after stopping document conveyance is executed in a slow-up control pattern that suppresses the occurrence of disturbance and loss of synchronization of read image data due to idling of the document. Can be.

Further, according to the third aspect of the present invention, at the time of the intermittent operation involving the stop and restart of the image data reading operation, the load state determining means determines the load state of the stepping motor when the reading operation is stopped by using the correlation table. The slowdown control pattern for executing the optimal fall control corresponding to the load state can be selected from the plurality of slowdown control patterns stored in the drive control storage unit, so that the load control can be performed. Even in the case of an intermittent operation having large fluctuations, it is possible to execute the document transport stop operation in a slowdown control pattern in which disturbance of read image data and occurrence of step-out due to idle running of the document are suppressed.

According to the fourth aspect of the present invention, at the time of the intermittent operation involving the stop and restart of the image data reading operation, the load state of the stepping motor at the time of stopping and restarting the reading operation is determined by the load state determining means. Can accurately grasp by referring to the correlation table, and execute the optimum fall and rise control corresponding to the load state from the plurality of slowdown control patterns and the slowup control patterns stored in the drive control storage means. Since a down control pattern and a slow up control pattern can be selected, even in the case of an intermittent operation with a large load variation, a slow down control pattern that suppresses the occurrence of disturbance of read image data and loss of synchronization due to idle running of the document. And a document transport stop operation and a restart operation can be executed with a slow-up control pattern. Therefore, the optimal drive control of the stepping motor is performed in both the stop and the restart due to the intermittent operation, so that the disturbance and the step-out of the image data can be further suppressed.

According to the fifth aspect of the present invention, at the time of the intermittent operation involving the stop and restart of the image data reading operation, the load state determining means determines the load state of the stepping motor at the time of stopping the reading operation by using the correlation table. Since the phase excitation pattern for executing the optimal braking control corresponding to the load state can be selected from the plurality of phase excitation patterns stored in the drive control storage unit, the phase excitation pattern can be accurately grasped by referring to, so that the load fluctuation is large. Even in the case of an intermittent operation, the original conveyance stop operation can be executed with a phase excitation pattern in which the disturbance of read image data and the occurrence of step-out due to the idle running of the original are suppressed.

According to the sixth aspect of the present invention, at the time of the intermittent operation involving the stop and restart of the image data reading operation, the load state determining means determines the load state of the stepping motor when the reading operation is stopped by using the correlation table. The slow down control pattern and the phase for executing the optimum fall control and the braking control corresponding to the load condition from the plurality of the slow down control patterns and the phase excitation patterns stored in the drive control storage means by accurately grasping the reference. Since the excitation pattern can be selected, even in the case of intermittent operation with a large load variation, the original is controlled by the slowdown control pattern and the phase excitation pattern that suppress the occurrence of disturbance of read image data and loss of synchronization due to idle running of the original. A transport stop operation can be performed.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a basic configuration of a document reading apparatus according to the first embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of a good facsimile apparatus to which the original reading apparatus of the present invention is applied.

FIG. 3 is a diagram illustrating a correlation between a document transport position and a load state of a stepping motor, which are referred to in a load state determination unit according to the present invention.

FIG. 4 is a flowchart showing a drive control procedure of the stepping motor according to claim 2;

FIG. 5 is a flowchart showing a drive control procedure of the stepping motor according to the third, fifth or sixth aspect.

FIG. 6 is a flowchart showing a drive control procedure of the stepping motor according to claim 4;

[Explanation of symbols]

REFERENCE SIGNS LIST 1 stepping motor 2 motor driver (drive control means) 10 controller 20 CPU 21 pulse number counting section (pulse counting means) 22 load state determination section (load determination means) 23 drive control pattern selection section (pattern selection means) 24 drive control Pattern storage unit (pattern storage means) 31 Document bundle 32 Document tray 33 Registration sensor 34 SIS 35 Discharge tray 40 Separation roller group 40a Pickup roller 40b Feed roller 40c Reverse roller 50 Transport roller group 50a Pull-out roller 50b Pull-out pressure roller 60 Discharge Paper roller group 60a Discharge roller 60b Discharge pressure roller 100 Document reading unit

Claims (6)

[Claims] 1. A sheet transporting type original reading apparatus which transports an original having image data by a roller driven by a stepping motor and sequentially reads the image data, counts the number of driving pulses supplied to the stepping motor. Pulse number counting means, pattern storage means for storing a plurality of drive control patterns for controlling the driving state of the stepping motor corresponding to the load state of the stepping motor for each document transport position, and image data of the document. Load determining means for determining a load state of the stepping motor at a stop position of the document according to the number of pulses counted by the pulse number counting means with respect to stop and restart of transport of the document when reading; From the plurality of drive control patterns stored in the pattern storage means, the load determination Pattern selecting means for selecting a drive control pattern corresponding to the load state of the stepping motor determined by the above, and drive control means for controlling the drive state of the stepping motor in accordance with the drive control pattern selected by the pattern selecting means A document reading apparatus comprising: 2. The original reading apparatus according to claim 1, wherein the drive control pattern of the stepping motor stored in the pattern storage means is a slow-up control pattern. 3. The original reading apparatus according to claim 1, wherein the drive control pattern of the stepping motor stored in the pattern storage means is a slowdown control pattern. 4. The original reading apparatus according to claim 1, wherein the drive control pattern of the stepping motor stored in the pattern storage means is a slow-up control pattern and a slow-down control pattern. apparatus. 5. The original reading apparatus according to claim 1, wherein the drive control pattern of the stepping motor stored in the pattern storage means is a phase excitation pattern. 6. The original reading apparatus according to claim 1, wherein the drive control patterns of the stepping motor stored in the pattern storage means are a slowdown control pattern and a phase excitation pattern. .