JPH0241698A - Image processor - Google Patents

Abstract

PURPOSE:To eliminate problems with respect to noise and driving speed and to optimally control to drive by driving a pulse motor in a phase exciting system responsive to an object to be driven. CONSTITUTION:A 2-phase pulse motor 26 is employed, and driven by 2-phase excitation, 1-2-phase excitation. That is, 1-2-phase excitation which can half step is selected to drive an optical system (exposure lamp units 4-7). Since this affects an influence to an image in the movement of the optical system, it is provided to smoothly operate it. The 2-phase excitation having large output torque is selected to drive a lens, thereby driving it for a large load.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an image processing device, and particularly to an image processing device using a stepping motor as a drive source for a load.

[Prior Art] Conventionally, as an image processing device such as a copying machine, there is one in which a single stepping motor drives a plurality of loads disposed in a reading system for reading images. In such a case, normally only the load such as the scanner is driven, and if the load is switched by an appropriate switching device, the load such as the lens may be driven instead of the scanner or the like.

In some cases, it is not possible to perform optimal control, which can lead to problems in terms of noise and load drive speed.

An object of the present invention is to enable optimal drive control corresponding to each of a plurality of loads, thereby solving the above problems.

[Means for Solving the Problems] To achieve this, the present invention provides an image processing device that is equipped with a means for independently driving a plurality of loads in a single stepping sequence, and that selects a load to be driven. The present invention is characterized by comprising a load switching means connected to the stepping motor, and a drive switching means switching the driving method of the stepping motor according to the load to be driven.

[Problems to be Solved by the Invention] However, in conventional image processing devices, the same driving method has been adopted regardless of the type of load. According to the above, when a single stepping motor drives different loads independently, the stepping motor drive method is switched depending on the load, so it is possible to perform drive control appropriate to the load.

[Example] Hereinafter, the present invention will be described in detail with reference to the drawings.

Note that the nut layer side will be explained using a copying machine as an example.

FIG. 1 is a sectional view of the entire copying apparatus regarding the wood layer side.

In FIG. 1, the drive system is divided into a main drive system that drives a paper feeding section, a conveyance section, a photoreceptor, and a fixing section, and an optical drive system that drives an optical system. An AC synchronous motor 25 is used as the main drive source, and a stepping motor (pulse motor) 26 is used as the optical drive source.

As the paper feeding method, feeding from the cassette 23 or feeding from the manual feed section 24 can be selected. When feeding paper from the cassette 23, the state is managed by a switch group 31 that detects the presence or absence of the cassette 23, a switch group 31 that detects the size of the cassette, and a switch 37 that detects the presence or absence of paper in the cassette. If an abnormality is detected in the above switch, it will be displayed on the display section which will be described later. The state of the manual feed guide 24 is managed by a switch 32 that detects the state, and when an abnormality is detected, it is displayed on a display section to be described later.

The photoreceptor 12 rotates clockwise in the figure. -Charger 13
The potential charged on the photoconductor 12 is exposed to light at an exposure position, which will be described in detail later, and developed in the development unit 15. transfer the image onto paper). After the transfer, residual toner is removed from the photoreceptor 12 by the cleaning unit 38, residual potential is removed by the pre-exposure lamp 16, and image formation is performed again. This process is repeated.

The transfer paper on which the image has been transferred rides on the conveyor belt of the conveyor unit 20 and is sent to the fixing unit 21. The fixing unit 21 is composed of a heat roller 35' having a temperature detecting element 35 such as a thermistor arranged on its surface, and a roller having an elastic surface which is in pressure contact with the heat roller 35'. The heat roller 35' uses a halogen lamp as a heat source, and this halogen lamp is built in in the axial direction of the roller.

This heating lamp is controlled by a thermistor so that the surface temperature of the heat roller 35' is a predetermined temperature.

The paper that has passed through the fixing unit 21 is ejected from the fixing unit 21 by a paper ejection roller 22 and transferred to a paper tray 39.
loaded on top. In addition, 34 indicates that the transfer paper is in the fixing unit 2.
This is a discharge sensor that detects whether or not the paper has passed normally.

As mentioned above, the drive source of the optical drive system is the pulse motor 26.
It is. The pulse motor 26 which is this drive source will later be used as the fifth motor.
As will be explained in detail in the drawings, the configuration is such that a completely different load is driven by operating the drive switching solenoid 27. 1
The two loads are the exposure lamp 4 and the first mirror 5. This is a unit that makes up the second mirror 6 and the third mirror 7, and the other load is a unit that makes up the zoom lens 8.

These loads that do not require synchronous driving can be driven by a common driving source.

The apparatus according to this example has a multi-stage magnification selection function by controlling the position of the zoom lens 80 and speed control of the lamp systems 4 to 7 by using the pulse motor 2G of the optical drive unit, and the reflected light of the document placed on the three surfaces of the document glass. A function to automatically select the density using the optical sensor 40 that detects the
automatic copy magnification selection function by connecting via communication means, various countermeasure functions in the event of an abnormality such as a paper jam, etc. , a page quick copying function by controlling the position of the exposure lamp 4 by IJ using the pulse motor 26, and a plurality of color images can be formed by replacing the developing unit 15. By providing this, it has a function of switching control depending on this state.

Next, the operation of this device will be explained.

FIG. 2 shows the operation panel of this device, which is arranged on the top surface of the device shown in FIG. When the I side of the power switch 51 is pressed, power is supplied to the device. At the same time, the power indicator lamp 5
2 is displayed lit.

The thermistor 35 of the fixing unit 2I detects that the heat roller 35' has not reached a predetermined temperature in the initial state after the power is turned on, and controls lighting of a fixing heater (not shown) as a heat source. When the power is turned on, the display on the operation panel is set as the standard mode, for example, as shown below. The number of sheets display 59 displays 1°', the magnification display 67 displays equal magnification, and A of the automatic density adjustment display 76 is lit.

Further, the display section of the start key 56 is displayed in red when the temperature inside the fusing unit has not reached the fusing temperature, and when it reaches the fusing temperature, the display changes to green and the copying operation is enabled. Show what happened. Normally, all other indicators are off.

Note that the fixable temperature of the fixing unit 21 varies depending on the type of the developing unit 15, and the set temperature is changed by determining the type of the developing unit 15 using a switch 36 provided on the developing unit 15. Further, when the temperature must be lowered from a high state, a forced cooling means such as an internal cooling fan 28 is provided to quickly reach the fixing temperature.

The transmission and reception of these signals related to the operation panel, temperature control, and control operations for the optical drive system, etc. described below, are performed by the third
It is controlled by the one-chip microcomputer shown in the figure. Q in FIG. 3 indicates a one-chip microcomputer with a built-in ROMRAM, and this one-deep microcomputer Q executes control operations according to a microcomputer program whose basic configuration is shown in FIG. 4.

Next, the operation of the optical drive system after power is turned on will be explained.

The exposure lamp systems 4 to 7 scan and move the original on the original glass 3 from the left end in FIG.
．． Second mirror 6, third mirror 7, zoom lens 8. Fourth
Mirror 9. The original is exposed to the photoreceptor 12 via the fifth mirror IO and the sixth mirror 11. In other words, set the starting point of movement to the left end. Set this position to the home position (
Hereinafter, it will be referred to as 1 (, P). This 11. +1 to detect P. A P sensor 29 is also provided. When the power is turned on, 11. When the position of the exposure lamp 4 is not detected by the P sensor, the control unit, which is in the form of a one-chip microcomputer, not shown in FIG. (For forward/reverse rotation control of the pulse motor, a known technique may be used.)

The start of the rotation control will be explained using FIG. 5. FIG. 5 shows an example of the configuration of a drive system in which two loads (optical system and lens) are driven independently.

Here, ■ is a lamp drive gear 26' that is integrated with the boob to drive the optical load (exposure lamp systems 4 to 7).
is the motor output gear provided on the output shaft of the pulse motor, ■ is the switching gear that meshes with gear 26' and selectively meshes with gear ■ or ■ to switch the load, and 27 is the link ■
Solenoid 1 for causing gear ■ to perform switching operation via
~, ■ are gears for driving the lens.

First, when the drive switching solenoid 27 is in the OFF state (there is no force b'), the switching motor moves in six directions by the IJ spring pressure. As a result, the output of the pulse motor 26 is connected to the lamp drive gear (2) via the switching gear (2), and the exposure lamp units 4 to 7 are driven. During this gear connection, the rotation speed of the pulse motor 26 is controlled to be sufficiently lowered when the switching gear (1) and the lamp driving gear (2) are engaged.

When the exposure units 4 to 7 or II, P are located, the pulse motor 26 drives the zoom lens unit 8. In other words, the zoom lens position before the power is turned on is unknown. As mentioned above, when the power is turned on, the same magnification value is selected as the standard mode. Therefore, temporarily return to the standard position,
An operation is performed to set the point at a predetermined position.

The above reference position is the zoom lens Baum position (Z,
(referred to as HP). A Z and IIP sensor 30 is provided to detect this position.

The operation will be explained with reference to FIG.

When the drive switching solenoid 27 is turned on, the solenoid 2
Move the plunger number 7 to the right. Therefore, due to the force b', the switching gear (2) moves to the right against the spring force. Due to this movement, the switching gear (2) and the lamp drive gear (2) are disengaged. By moving roughly to the right, the switching gear (2) meshes with the lens drive gear (2). The rotation control when the gears are engaged is the same as described above.

The zoom lens 8 has a magnification of 200% when the lens position is located near the 7 and 11 P sensors, with the Z and II P sensors as the reference position, and a reduction ratio of 50* when the lens position is moved further to the right. Performs position control.

At the start of zoom lens driving, the operation is determined as follows depending on the states of Z and lIP.

(1) When the position of the zoom lens 8 is detected by the z and OP sensor.

(1) Move the -1-degree zoom lens 8 to the right and set Z, lI
Move it out to a range where it is not detected by the P sensor and stop.

(1)-2 Move to the left, move a predetermined distance from the point at which the Z and II P sensors are detected, and then stop.

However, if Z,)II' sensor does not detect the position of the zoom lens, execution starts from operation (1)-2.

The above operation is necessary control to prevent setting position errors due to gear neck backlash.

After this, move the zoom lens 8 to the right again, move the zoom lens 8 or Z from the position outside the HP sensor to a predetermined position, that is, in the case of the standard mode setting, move to the position corresponding to the same magnification and stop. do. After this, the drive switching solenoid 27 is turned off. As a result, the switching gear (2) moves in the direction of meshing with the lamp driving gear (2) as described above. However, in order to achieve smooth meshing, it is necessary to rotate the switching gear (2) as already mentioned.

At this point, the exposure lamp units 4 to 7 are at H, P29. Therefore, the pulse motor 26 is connected to the exposure lamp unit 4.
~ Rotate 7 in the direction of moving it to the right. As a result, when the exposure lamp units 4 to 7 are disengaged from the H and P sensors 29 (this means that the switching gear ■ and the lamp drive gear ■ have finished mating), the rotation is stopped, and the rotation is started again in the opposite direction. 11. After detecting the P sensor 29, it stops at a predetermined position.

The initial operation of the optical drive system and the fixing unit 21 explained above
When the fixing temperature is reached, the preparation for multiple operations of the apparatus is completed.

Next, the copying operation by feeding paper from the cassette 23 will be explained.

When the copy start key 56 is pressed, the transfer paper size data is generated by a manual signal from the switch group 31 that detects cassette size, the number of sheets is set by the number key 54, and the magnification selection keys 81, 62, 64, 65.66 The copying operation is started based on the magnification data obtained by the image forming apparatus and data obtained by various other mote selection means.

When the copy start key 56 is received, the display G changes from green to red, and the number key 54 and magnification key 61626 are pressed.
Input of mode switching keys such as 4, 65, and 66 is prohibited.

The main drive motor 25 starts rotating, and the yarn feeding roller 18
．． Photoreceptor 12.1lfj feed unit 20. Fixed uni・
The driving force is transmitted to the components 21 and the like.

Furthermore, when the copy key 56 is pressed, the fixing temperature of the fixing unit 21 is changed depending on the cassette size data.

0.5 seconds after the main drive motor 25 starts rotating, the paper feed solenoid (not shown) operates, the paper feed roller 17 rotates accordingly, and the transfer paper in the cassette 23 is transferred to the paper feed roller 18. Send in the direction. The transfer paper feed amount of the paper feed roller 17 is controlled by cassette size data. In other words, if the transfer paper is larger than a predetermined value, the amount of feed is increased. When the transfer paper reaches the paper feed roller 18, the transfer paper
The paper feed roller 18 feeds the paper to the registration rollers 19 and stops there. A manual feed switch 33 installed between the paper feeding roller 18 and the registration roller 19 detects the feeding state of the transfer paper.

At a predetermined timing until the transfer paper is sent along the paper feed path and reaches the registration rollers 19, the exposure lamp units 4 to 7 are allowed to start scanning the document. At this time, the exposure lamp is at a position where it can be detected by the H, P sensor 29. More specifically, during the initial operation or during the backward movement of the copy operation, 11. It stops at a position that is a distance or backwards from the position where the P sensor is detected, depending on the selection magnification at that time.

With the start of document scanning, the novel motor 26, which is an optical system drive source, moves the exposure units 4 to 7 forward (to the right) until the drive pulse rate corresponding to the selected (fz, rate value) is reached. Pulse rays 1 to 1 are gradually increased (referred to as slow-up control) until the target speed is reached.In other words, the moving speed is gradually accelerated until it reaches the target speed. system, and has a configuration in which the drive current value can be switched in multiple stages (two stages in the example) (selected by the pH4 output signal of the optical drive pulse motor control signals shown in Figure 3). ing).

Generally, the characteristics of a pulse motor are such that the pull-in torque decreases as the pulse rate increases.

For this reason, a means for switching the constant current setting value is provided, and the current value is switched as necessary.

In this device, the set current is kept low during a relatively low pulse rate from the start of movement, and the set current value is increased from the point when the speed exceeds a predetermined value, and after reaching the target speed, the set current value is controlled to be increased. As time passes, control is implemented to lower the set current value again. This is mainly aimed at preventing noise, temperature rise, and step-out phenomena of the pulse motor.

Next, a method for forming a margin at the leading edge of the image and a method for aligning the leading edge with the transfer paper will be explained using FIG.

As a means to prevent toner damage in non-image areas, LE
Although static elimination means using light sources such as D lamps and fuse lamps are generally used, this device uses a primary charging unit 13.
A similar effect is achieved by controlling the voltage value of the glyph F13' provided in the image. This is an important method in the current situation where it has become difficult to arrange a plurality of members around the photoreceptor due to miniaturization of devices. Since the distance between the exposure point and the grid cannot be placed sufficiently short compared to the distance between the H and P sensor 29 and the document placement position, the movement of the exposure lamp 4 is started in order to form a margin of 2 mm at the leading edge of the document. After a predetermined period of time corresponding to the selected magnification value, the voltage I~ is switched from the L level to a predetermined voltage. In other words, when the grid voltage is at the L level, the photoreceptor is not charged with potential, so a toner image is not formed, and an image is formed from the timing when the voltage is switched to the above-mentioned predetermined voltage. It forms a margin.

Next, regarding alignment of the leading edge of the image with the transfer paper, the distance C between the exposure point and the transfer section is made shorter than the distance C between the registration roller 19 and the transfer section. For this reason, before the image at the leading edge of the document is actually exposed on the photoreceptor 12, it is necessary to re-feed the transfer paper waiting in the registration roller 19 section mentioned above and send it toward the transfer section.

In this apparatus, when the exposure lamp 4 starts moving and reaches the target speed, the H and P sensors 29 are still detecting the movement. The value obtained by dividing the value of distance + 2 mm from the timing of passing the H, P sensor 29 by the speed according to the selected magnification is the time when the exposure lamp 4 reaches the end of the white board after passing the H, P sensor 29. There is a time required for
Let this time be X. Also, from the time from the start of paper refeeding by the registration roller 19 until the transfer paper reaches the transfer section,
The value obtained by subtracting the time required for the image at the exposure point of the photoreceptor 12 to reach the transfer section is y, and the transfer paper is placed at a distance of 2 mm from this y.
Time required to send (2mm÷100mm/s-0, [
12 sec...conveying speed-toOmm/s) is added. The above values are calculated using the following formula.

x - (y 10.02) = Z (sec) In other words, the registration roller 19 is operated at the timing when the above formula value Z has passed from the time when the paper passes the H9P sensor 29, and the paper is re-feeded. 2mm margin depending on the magnification
A formed transfer paper image is obtained.

The scanning distance of the exposure units 4 to 7 is moved a predetermined distance according to the cassette size data, magnification data, etc., and when the target position is reached, the pulse rate is gradually decreased (called slowdown control) and stopped, and then returned to H. , and performs slow-up control and constant speed control in the direction of the P sensor 29 to move backward. And 11. P
When the sensor 29 is detected, slowdown control is performed to stop the exposure units 4 to 7 at a position corresponding to the selected g rate.

The manual copy operation is started when the manual feed sensor 33 detects the inserted transfer paper.

The main drive motor 25 starts rotating, which causes the paper feeding roller 18 to rotate. As a result, the inserted transfer paper is transferred to the registration roller 19 by the paper feed roller 18.
sent in the direction. Further, after a predetermined period of time from the time when the manual feed sensor 33 detects the transfer paper, the exposure lamp unit 4
-7 document scanning start is permitted. The subsequent operations of the exposure lamp system and the leading edge of the transfer paper are the same as in the case of cassette paper feeding, and will therefore be omitted. Next, the rear edge of the transfer paper is at the manual feed sensor 3.
The operation of the registration roller 19 is stopped when the time X' required for the transfer sheet to pass through the distance between the manual feed sensor 33 and the transfer section has elapsed from the time when the transfer sheet passes through the transfer section 3. However, if the manual feed sensor 33 detects the next sheet while measuring X', the time required for the transfer paper to pass the distance mt between the manual feed sensor 33 and the registration roller ]9 will elapse. The operation of the registration roller 19 is stopped.

Further, the document scanning distance is also controlled by the rear end of the transfer paper (No. 8).

As shown in "2" below, the pulse motor 26 drives the exposure lamp units 4 to 7 and the zoom lens 8 independently, or the pulse motor 26 drives the exposure lamp units 4 to 7 and the zoom lens 8 independently. Performs pulse motor control such as.

As is well known, a pulse motor rotates according to an excitation pattern input to each phase. In the case of a two-phase pulse motor, there are the following three excitation patterns.

a) 1-phase excitation b) Two-phase excitation/large output torque c) 1-2 phase excitation: Can be driven in half steps.

In this example, a two-phase motor is used as the pulse motor 26, and driving is performed using two-phase excitation and 12-phase excitation. In other words, for driving the optical system (exposure lamp units 4 to 7), 1-2 phase excitation, which can be half-stepped, is selected. This is to ensure proper driving.And,
Two-phase excitation with large output torque is selected to drive the lens, making it possible to drive the lens even under large loads.

FIG. 7 shows an example of a control section related to the main part of this embodiment.

Here, 101 is a controller that drives a motor 26 and a load switching solenoid 27 for driving the optical system and lens, which are loads, and is a simplified representation of a one-chip microcomputer Q that executes a series of copy sequences. .

102 is a constant current driver for driving the pulse motor according to excitation signals A, A, B, and B.

In the above configuration, a mode of switching the excitation method according to the load will be explained.

FIG. 8(A) shows an example of a control procedure when the power is turned on. When the power is turned on, first in step 5121 it is determined whether the optical system (exposure lamp units 4 to 7) is at the home position, and if a negative determination is made, 1
- Drive the pulse motor 26 with two-phase excitation and set the optical system to the Bauhm position (step 5131).

Thereafter, in order to position the zoom lens 8 to the set position, the optical system/lens switching solenoid 4 is turned on (step 5122), and the process waits for a predetermined time until the solenoids 1 to 4 are completely turned on (step 5122). 5123), and moves the lens 8 in the direction of the lens Bauhm position (2/11P) using two-phase excitation (step 5124).
), and is driven a distance corresponding to the set magnification from Z/HP (step 5125). After completing this setting, the optical system/lens switching solenoid 4 is turned off (step 5127) after waiting for a predetermined time (step 512B). Further, wait for a predetermined time (step 5128), 1-2
The optical system is temporarily moved out of the detection position of the home position sensor by phase excitation (step 5129), and then the optical system is stopped at the home position where detection is performed by the home position sensor again (step 5130).

Next, the operation when the copy key 58 is turned on will be described using FIG. 8(B). When the copy star milk key 56 is pressed (step 5132), it is determined whether or not there is a change in the set magnification, and if it is determined that it is fixed, the same processing as steps 5122 to 5130 is performed in step 5134. . Then, a series of appropriate copying processes 3 as mentioned above! [! (Step 5135) is performed.

As described below, in this embodiment, noise and drive speed are reduced by driving the pulse motor that independently drives the optical system and lens using a phase excitation method depending on the drive target. This makes it possible to perform optimal drive control without causing any problems.

In the following, the present invention is applied to an image reading system of an image processing apparatus in the form of a copying machine, but it is of course applicable to any appropriate part of an image processing apparatus in an appropriate form. It is.

[Effects of the Invention] As explained above, according to the present invention, by providing a means for switching the excitation method of the stepping motor (pulse motor) that is the drive source, the optimum drive according to the load can be achieved with a simple configuration. It has the effect of being able to be controlled and reducing noise. Furthermore, since such control can be performed using a single motor, it is advantageous in terms of cost.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a copying apparatus according to an embodiment of the present invention, FIG. 2 is a plan view showing an example of the configuration of the operation panel of the apparatus shown in FIG. 1, and FIG. A block diagram showing a one-chip microcomputer that performs all the controls, Fig. 4 is an explanatory diagram showing an example of the basic configuration of the program of the one-chip microcomputer shown in Fig. 3, and Fig. 5 shows a switch for switching the load driven by the pulse motor. An explanatory diagram showing an example of the configuration of the system. Figure 6 is a diagram for explaining the formation of a margin at the leading edge of an image and alignment of the leading edge with the transfer paper. Figure 7 shows a control system related to the main part of this embodiment. Block Diagram FIGS. 8(8) and 8(B) are flowcharts showing an example of the control procedure of this embodiment. 4... Exposure lamp, 5.6, 7, 8, 9, 10. ll 12...Photoreceptor, 13...Charger, 14...Transfer unit 1-. 15...Developing unit, 20...Transporting unit, 21...Fixing unit, 26...Pulse motor, 27...Drive switching solenoids 1-. 29...1 (-P sensor. ...Mirror section C square diagram (B)

Claims (1)

[Scope of Claims] 1) An image processing device comprising means for independently driving a plurality of loads with a single stepping motor, comprising: load switching means for selecting a load to be driven and connecting it to the stepping motor; An image processing apparatus comprising: drive switching means for switching a drive method of the stepping motor according to a load to be driven. 2) A reading means for reading image information from a document, the reading means having an optical system for scanning the image information during the reading, and a zoom lens for changing the reading magnification, The plurality of loads are zoom lenses, the stepping motor has a form of a two-phase stepping motor, and the drive switching means selects a 1-2 phase excitation method and a 2-phase excitation method when driving the optical system and the zoom lens, respectively. An image processing device characterized in that the two-phase stepping motor is driven by an excitation method.