JPS63241534A - Image reader - Google Patents

Abstract

PURPOSE:To reduce the cost of production and to simplify a control circuit by driving a scanning means by a permanent magnet type pulse motor. CONSTITUTION:The pulse motor 51 is constituted of a rotor 51a disposed with plural permanent magnets around the same and a stator 51c wound with a coil 51b disposed around the rotor 51a. A 1st carriage 411 and a 2nd carriage 412 are driven by this permanent magnet type pulse motor 51, by which the number of driving pulses is decreased as compared to the case in using the conventional composite type pulse motor. The formation of the motor driving circuit to the simpler configuration is thereby permitted and the cost of producing a copying machine is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to an image forming apparatus applied to, for example, an electronic copying machine.

(Prior Art) As is well known, in a conventional electronic copying machine, an optical scanning means for exposing and scanning a document is driven by a compound pulse motor. As shown in FIG. 8, this composite pulse motor includes a rotor RT magnetized in the axial direction, a rotor R
A plurality of coils CL are connected to the stator S1- arranged around T.
It has a structure in which it is wound. Therefore, this composite pulse motor has a complicated and expensive structure, and the cost of the electronic copying machine itself has also increased.

Furthermore, the number of pulses supplied to the above-mentioned conventional compound pulse motor is 0,125 +u+/
In the case of 5 tep, as shown in FIG. 9(a), for example, 1328 PPS at SC when scanning a document, and 2 at RE at return to the standby position after scanning is completed.
500PPS.

Also, the amount of movement per step is o, i mm/5te
o, as shown in the same figure (b), SC during scanning: 1
252.3PPS, RE on return: 2340PP
S and is designed to be driven by a high rate pulse signal. Therefore, the circuit configuration for driving this composite pulse motor becomes complicated.

(Problems to be Solved by the Invention) The present invention is intended to solve the problems associated with the increase in manufacturing costs and the complexity of the control circuit due to the use of a compound pulse motor, and its purpose is to: It is possible to suppress the rise in manufacturing costs], and
It is an object of the present invention to provide an image forming apparatus whose control circuit can be simplified.

[Structure of the Invention] (Means for Solving the Problems) The present invention provides a scanning means for exposing and scanning a document image, a transfer means for transferring an optical image guided by the scanning means onto a transfer material, and a method for scanning the original image. It consists of a permanent magnet type pulse motor that drives the device.

(Function) The present invention aims to reduce the manufacturing cost and simplify the control circuit by driving the scanning means with a permanent magnet type pulse motor.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 5 and FIG. 6 schematically show an image forming apparatus of the present invention, for example, a multiplex copying machine. That is, 1 is a main body of the copying machine, and a document table (transparent glass) 2 is fixed to the upper surface of the main body 1 for holding a document. This document table 2 is provided with a fixed scale 21 that serves as a reference for setting the document, and furthermore, a document cover 1 that can be opened and closed is provided near the document table 2.
1 is provided. Therefore, the original placed on the original platen 2 is exposed to light by an optical system consisting of an exposure lamp 4 and mirrors 5, 6, and 7 reciprocating along the lower surface of the original platen 2 in the direction of arrow a. Exposure scanning is performed during reciprocation. In this case, mirror 6.7 moves at a speed of 1/'2 of mirror 5 so as to maintain the optical path length. The light emitted from the original by the scanning of the optical system, that is, the exposure lamp 4
The reflected light from the original due to the light irradiation is reflected by the mirrors 5, 6, and 5.
7, passes through the variable magnification lens block 8, is further reflected by mirrors 91, 92, and 93, and is guided to the photoreceptor drum 10, so that the image of the original is formed on the surface of the photoreceptor drum 10. It has become.

The photosensitive drum 10 rotates in the direction indicated by the arrow in the figure, and the surface is first charged by the charging device 11, and then the image is exposed to slit light at the exposure section Ph, thereby forming an electrostatic latent image on the surface. be done.

This electrostatic latent image is produced by a developing device 12 that contains, for example, red or black toner, and is selectively operated as required.
1.Is it possible because the toner is attached by 122?
Ja 11 is now available.

The developing units 121 and 122 are detachably attached to the copying machine main body 1, and the color of the toner contained in these developing units 121 and 122 can be determined by, for example, a connector (not shown) provided on the copying machine main body. It is set by the connection status of multiple bins.

On the other hand, the paper (transfer material) is sent out from the selected upper paper feed cassette 131 or lower paper feed cassette 132.
- The sheets are taken out one by one by the rollers 14r, 14z and the roller pair 151, 152, guided through the paper guide path 161, 162 to the registration roller pair 17, and guided to the transfer section by the registration roller pair 17. ing.

Here, the paper feed cassettes 131 and 132 are removably provided at the lower right end of the main body 1, and either one can be selected on the operation panel described later. Further, the cassette size of each of the paper feed cassettes 131 and 132 is detected by a cassette size detection switch 6C) 1.602.

The cassette size detection switches 601 and 602 are composed of a plurality of microswitches that are turned on and off according to the insertion of cassettes of different sizes.

Furthermore, a manual feed guide 13a is provided on the upper surface of the paper feed cassette 131.
The paper manually inserted through the feed roller 14a
The sheet is guided to the pair of rollers 151 by the roller pair 151, and is then conveyed in the same manner as sheets fed from the sheet feed cassette 131.

On the other hand, the paper sent to the transfer section comes into close contact with the surface of the photoreceptor drum 10 at the transfer charger 18, so that the toner image on the photoreceptor drum 10 is transferred by the action of the charger 18. . This transferred paper P is transferred to the peeling charger 1
The transferred image is electrostatically separated from the photoreceptor drum 10 by the action of step 9, is conveyed by a conveyor belt 20, and is sent to a fixing roller 21 as a fixing device provided at the end of the conveyor belt. It will be established. After fixing, the paper is discharged to a tray 25 outside the main body 1 by a pair of delivery rollers 22. Further, the photosensitive drum 10 after the transfer is removed by the cleaning blade 26a of the cleaner 26.
The residual toner on the surface is removed by the static elimination lamp 27, and the residual image is erased by the static elimination lamp 27, thereby returning to the initial state. Note that 29 is a cooling fan for preventing the temperature inside the main body 1 from rising. Further, the exposure lamp 4 and the mirror 5 are provided in the first carriage 41r,
The mirror 6.7 is mounted on the second carriage 412.

Further, the first carriage 411 is provided with a spot light source 131 that is movable in a direction orthogonal to the moving direction of the first carriage 411.

Furthermore, an erasing array 15 in which a plurality of light emitting elements are arranged along the longitudinal direction of the photoreceptor drum 10 is located between the charging band N unit 11 of the photoreceptor drum 10 and the exposure section Ph.
0 is provided, and when performing partial erasure of a document image, the light emitting elements constituting this erasure array are turned on corresponding to the erasure area designated by the spot light source 131, for example, and the light emitting elements of the photoreceptor drum 10 are illuminated. It is designed to remove static electricity. For this reason, the part where the charge has been removed (well,
Thereafter, since no electrostatic latent image is formed in the exposure portion ph even after exposure, the original image is erased.

FIG. 7 shows an operation panel 30 provided on the main body 1 of the copying machine. 30 a + is a copy key for commanding the start of copying, 30 b is a numeric keypad for setting the number of copies, etc.
30C is a display section that displays the operating status of each section and paper jams, etc.; 30d is a 711 degree setting section that sets the copy density;
30e is a count command key for displaying the total number of copies and the number of copies for each color; 30f is an interrupt key operated when another person makes another copy while copying; 30Q
is the same magnification key to set the copy magnification to the same magnification (100%), 30h is the magnification key to be operated when setting the copy magnification, 30i is the upper and lower paper feed power settings 131.132
A cassette selection key 30j is operated to select a toner, a color change key 30j is operated when copying with a different toner color, and 30 is operated, for example, the edit key 30n. The mode memory key 301 is operated to store the specified erasure range in the memory or to read out information on the erasure range etc. stored in the memory in advance. This is an information key that is operated when you want to obtain information. For example, if you operate this key when a paper jam occurs, the display 30 (described later) will be displayed.
Information for clearing paper jams is displayed at o.

30m is a function check key, and by operating this function check key 30m, it is possible to display on the display 30o what kind of function is set. Reference numeral 30n denotes a wA center key which is operated when performing partial deletion, multiple copying, double-sided copying, etc. in which a part of the original image is erased and copied. 300 is a display device consisting of, for example, a liquid crystal dot matrix panel, and this display device 3
For example, the setting status of the copying machine is displayed in characters at 00, and when the various keys 30e, 30f, 30g to 30m are operated, the corresponding characters are displayed. Furthermore, if a paper jam occurs during a copying operation, for example, the display 300 displays the location of the paper jam and countermeasures using text and graphics. This display 30o
Operation keys 301 to 30 and 305 to 308 for selecting various functions displayed on the display 30o are provided on both sides of the screen. Also, 30p is the spot light source 1 mentioned above.
This is a movement key to move 31, and this movement key 30p
can be tilted in all directions as shown by arrows 30q to 30t, and when these arrows 30CI to 30t are operated,
The spot light source 131 is moved in the same direction. 30u is a position designation key for inputting the coordinate position indicated by the spot light source 131.

FIG. 1 shows the main part of the present invention, and the first carriage 411 and the second carriage 412 are driven by a permanent magnet type pulse motor 51. That is, the power of this pulse motor 51 is transmitted to the pulley 52,
The signal is transmitted to a pulley 55 by a speed reduction device consisting of a belt 53 and a pulley 54. A wire 56 to which the first carriage 411 and the second carriage 412 are fixed is hung around the pulley 55.

FIGS. 2(a) and 2(b) show the permanent magnet type pulse motor 5.
1. This pulse motor 51 is shown in the same figure (
As shown in 1)), it is composed of a rotor 51a around which a plurality of permanent magnets are arranged, and a stator 51C which is arranged around the rotor 51a and around which a coil 51b is wound.

FIG. 3 shows the main parts of the control circuit. , υ control section 100 controls the operation of the entire copying machine, and this control section 100 includes the aforementioned operation panel 30, a solenoid 26b1 that drives the cleaning blade 26a, a static elimination lamp 27, and a lighting control for the exposure lamp 4. Connected thereto are a lamp regulator 101 that operates as shown in FIG.

In the above configuration, the permanent magnet type pulse motor 51 is driven by the motor drive circuit 103 as follows. That is, as shown in FIG. 4, the acceleration time ta (ills) in SC during exposure scanning, the deceleration time tb (IIIS) in SC during exposure scanning, the duration tC (ms) of exposure scanning,
The acceleration time td (ms) at RE during return, the deceleration time te (ffls>) at RE at return, and the holding time tf (ms) after return are each 50 (ms), and the deceleration consisting of the pulleys 52, 54 and belt 53 The reduction ratio of the device is set to 1/2. The moving distance of 11 steps is set to 0.2.
08 (am), and it is possible to copy 18 A4 sheets per minute, the number of pulses supplied to the permanent magnet type pulse motor 51 is 480 PPS during exposure scanning and RE: 726 PPS during return.

Also, under the same conditions, the number of SC pulses during exposure scanning was increased to 500.
When set to PPS, the number of RE pulses at return is 6.
It becomes 48PPS. Furthermore, the moving distance of one step is reduced to 0.
．． 219 (++1), when the reduction ratio is 1/1.9 and other conditions are the same, if the number of SC pulses during exposure scanning is set to 462 PPS, the RE at return is 66
It will be 4PPS.

According to the above embodiment, by driving the first carriage 411 and the first carriage 412 with the permanent magnet type pulse motor 51, it is possible to reduce the number of drive pulses compared to the case where a conventional composite type pulse motor is used. It is. Therefore, the configuration of the motor drive circuit 103 can be simplified compared to the conventional one.

Further, since the permanent magnet type pulse motor 51 has a simple configuration and is inexpensive, it is possible to reduce the manufacturing cost of the copying machine itself.

Note that this invention is not limited to the above embodiments,
Of course, various modifications can be made without departing from the gist of the invention.

[Effects of the Invention] As described in detail above, according to the present invention, an image forming apparatus is provided in which the scanning means is driven by a permanent magnet type pulse motor, thereby reducing the manufacturing cost and simplifying the control circuit. Can be provided.

[Brief explanation of drawings]

FIG. 1 shows an embodiment of the present invention. FIG. 2 is a side view schematically showing the drive system; FIG. 2 shows a permanent magnet pulse motor; FIG. 2A is a side sectional view; FIG. Figure 3 shows t+
11wJ system; FIG. 4 is a diagram for explaining motor drive control according to the present invention; FIG. 5;
6 shows the configuration of the image forming apparatus, FIG. 5 is an external perspective view, FIG. 6 is a side sectional view, FIG. 7 is a plan view showing the configuration of the operation panel, and FIG. 8 is a composite This figure shows a type pulse motor, and the figure (a) is a side sectional view and the figure (a) is a side sectional view.
b) is a front view showing the stator, and FIG. 9 is a diagram shown for explaining conventional motor drive control. 1... Copying machine main body, 30... Operation panel, 411.
...First carriage, 412...Second carriage, 5
DESCRIPTION OF SYMBOLS 1... Permanent magnet type pulse motor, 100... Control part, 103... Motor drive part. Applicant's agent Patent attorney Takehiko Suzue Figure 3 C E Figure 114

Claims (1)

[Claims] An image forming apparatus having a scanning means for exposing and scanning an original image, and a transfer means for transferring an optical image guided by the scanning means to a transfer material, wherein the scanning means is driven by a permanent magnet type pulse motor. An image forming apparatus characterized by: