JPS6043640A - Electrophotographic copying device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for driving a reciprocating object with good start-up and at a constant speed, and in particular, the present invention relates to a device for driving a reciprocating object with good start-up and at a constant speed. The present invention relates to a device for driving a moving body. Although the present invention can be applied to various types of devices, the description will be limited to the driving device of a copying machine.

Rotating torque from a motor or a clutch directly connected to the motor is used to reciprocate the document table in the case of a copying machine with a moving document table or the optical mirror in the case of a copying machine with a moving optical system. When moving, the wire winding creates a tight side and a loose side on both sides of the pulley. When the pulley is reversed, the winding suddenly switches from the slack side to the tight side, which prevents the moving object from instantaneously reaching a constant speed.1. A sudden shock can also cause the wire to break. Furthermore, compared to the sudden activation of a motor or clutch, a moving object cannot follow the movement as rapidly due to inertia. Therefore,
The energy from the shock at startup is transferred into the wire.
It is stored in time and causes the initial vibration of the moving object. Although this initial vibration is gradually absorbed by the frictional force of the wire tension system, it takes a long time to do so. In particular, in the exposure stroke (forward movement) of a copying machine, a long run-up section is required prior to exposing the original.

In addition, to prevent permanent stretching of the wire, a tensioner is installed on the reciprocating side of the pulley when winding the wire, which has the effect of absorbing the strain, but the initial shock caused by the initial shock when starting the motor or clutch causes the wire to be stretched. − “It cannot absorb vibrations (which inevitably lead to vibrations of the moving object).Moreover, the tension on the tensioner is small compared to the tensile strength of the wire, so that it does not vibrate when the moving object moves back. ht etc., which often has an adverse effect on various parts of the device.

DESCRIPTION OF THE PREFERRED EMBODIMENTS A conventional copying machine driving device will be described below with reference to the drawings. Although the drawings show the case of a copying machine with a moving optical system, exactly the same applies to a copying machine with a moving document table.

In FIG. 7, the operation of the optical system will be briefly explained together with the operation of the copying machine. The document forming the document placement surface on the top of the machine box is placed on the Cusco.

When the copy button is pressed, the photosensitive drum 3 starts rotating in the open direction as shown. When the drum 3 reaches a predetermined position, a signal to start exposure is issued, and the illumination lamp and first mirror S, which are the movable parts of the optical system, move toward the right in the figure at the same speed as the circumferential speed of the photosensitive drum 3. The Ω mirrors 6 also start moving toward the right in the figure at half the speed. Manuscript/
The image is irradiated by an illumination lamp and formed on the photosensitive layer on the surface of the photosensitive drum 3 by an optical system consisting of a first mirror S, a second mirror B, an in-mirror lens 7, and a fixed mirror g. When the first mirror S and the Ω-th mirror 4 move to the positions 3/ and O' indicated by the imaginary lines in the figure, the exposure ends, and the optical moving unit detects the position and moves to the right by one stroke. Then, immediately return in the opposite direction, that is, to the left. The surface of the photosensitive drum 3 is uniformly charged by the primary charger 9, and then exposed to light as described above when it reaches the image forming part /θ at The entire surface is exposed by the lamp /2, and an electrostatic latent image is formed on the drum surface.Furthermore, the liquid is developed by the liquid developer /3, and the remaining liquid is squeezed by the aperture charger /da.Next, the drum is used for transfer. The image on the drum 3 is transferred by the charger 15 onto the copy paper 7g sent from the paper feed section /O or /7.The transferred copy paper is pulled from the drum by the separation section /7. After fixing, the tray 2 is guided by the fixing section λθ.
/ is discharged. On the other hand, the drum surface is cleaned by the blade cleaner 22 pressed against it, and the next cycle becomes possible again.

As shown in the explanation on the second side, the exposure optical system of a copying machine requires a device that drives the first mirror and the second mirror at a speed ratio of 22/14 reliably. . Below, a conventional mirror drive device using steel wire will be explained.
, wire diameter 0. / m, 7×7, outer diameter i Q +
nm nylon coated steel wire was used.

In Fig. Ω, the first mirror 57 is fixedly disposed on the first support part S2 at a certain angle inclined with respect to the horizontal, and the first mirror S3 is fixedly supported vertically by the first support part +71S da. has been done. On both sides y1'Mj of the third mirror 57 and the second mirror S3, there are guide shafts 33 parallel to the mirror along the moving direction of the first mirror 57 and the first mirror 53. 'f;A, , 37 are arranged through other parts. The first support member Sλ is slidably fitted on the guide shaft 55 at one end, and supported at the other end by a rotatably attached roller 5g so as to be slidable on the guide shaft s7. Similarly, the arm parts 51Ia and 54b at one end of the first support part 4; supported in a movable manner. A movable pulley B is provided on the arm portion 311h and the arm portion S of the support portion S, respectively.

and a first movable pulley O/ are arranged to rotate freely. Guide shaft5. , ff, to the left of 5B in the figure is the movement Q6 of the first support part A'A' 52, to the left of the circle C). A first movable pulley O/ is installed at a fixed position and freely rotatable, and a first movable pulley O/ is installed at a fixed position and freely rotatable to the right of the movable enclosure of the second movable boot υ-40 in the drawing. ing. There is a winding pulley 6 fixed to the drive shaft A at the lower intermediate position between the 1st/fixed boolean Ω and the λ fixed boolean J-A3, and the drive shaft A is connected to the motor or motor and clutch. The combination is arranged in a fixed position so that the city can be reversed. Furthermore, between the first movable pulley B/ and the wrapped pulley S, a pulley that can freely swing around the fixed axis B is installed. is arranged, and the spring 9
Therefore, the winding f=I is always pulled toward the pulley S side. The optical drive wire 70 has one end Oa fixed to a fixed plate 7 fixedly attached to the main body, and is connected to the first support member 52 via a third movable pulley. ．． 21
It is further fixed through the first movable pulley B/, and is wound several times around the pulley O through Ten V Yonpu 9 = 6g, through the first movable pulley O/, and the first movable pulley O/. The other end 70d is fixed to the fixing plate 7/. Now, the wrapping is boo! When J-45 rotates in the direction of the arrow in the drawing, part 70b of wire 0 is wound around pulley O S, and conversely, part VOc of wire is let out by the same length. As a result, the first support part shrine 52 is connected to the pulley S
It moves to the arrow side at the same speed as the winding speed of
The driving pulley 4/ moves in the same direction as the second/supporting member 52 at half the wire winding speed. The first movable pulley O/ is fixed to the 7th support member.
It moves in the same direction as the supporting part 3.2, and at 1/2 the speed. On the other hand, the wire 70c loosens by that amount, but this is offset by the movement of the λ-th movable pulley /)o in the direction of the arrow, and the wire 70 as a whole does not loosen. Similarly, when the winding is performed, if the boot IJ-, 43 is rotated in the direction opposite to the arrow, the first support portion 52 and the second support portion paulownia 54 are rotated 2:/
move at a speed of In this way, the second mirror S3 and the second mirror Shio 3 can be connected without changing the overall length of the wire 7o.
are guaranteed to move in the same direction and at a speed of 2:/.

The direction of the arrow in FIG. 2 is the exposure process of the original. At the moment when the exposure process is finished and the wire 70 starts to rotate in the opposite direction to the arrow, the tension side and the slack side of the wire 70 are reversed, so the part 70c of the wire becomes the tension side and the tension is increased. The pulley Og is swung counterclockwise with respect to the pulley A.

Conversely, part 0b of the wire becomes slack, and until that slack is absorbed by spring Otsu 7, the speed of the seventh mirror 3/and second mirror S3 is not completely transmitted to the right hand of pulley A5. . However, the return stroke of such an optical system does not pose much of a problem without image irradiation. On the other hand, when the winding roller Otsu S enters the exposure process, a portion 70b of the wire becomes tight and a portion 70C of the wire becomes loose. part of wire 70
When C becomes loose, the tension pulley 4g is swung in the direction 1 around the heel 6 by the tension spring 9 in order to absorb the slack. However, the absorption of slack in the wire by this tension spring is much slower than the speed at which the wire loosens, and the optical system is shaken by the shock when the motor or clutch is started.
During the uJ period of the exposure process, the speed of the movable mirror and the speed of the winding pulley do not match. Therefore, during this period, the original cannot be exposed due to the discrepancy between the mirror speed and the drum circumferential speed. Since the document can be exposed from the time when the mirror speed and the drum circumferential speed match, the period until then becomes an unnecessary run-up period. Moreover, the shock caused by switching the wire between the tight and loose sides significantly shortens the life of the wire. In addition, due to friction between the steel wire and the pulley or between the steel wires, the nylon coat may peel off.
Frays and the like occur due to strand breakage, which may cause the device to move or ultimately cause the steel wire to break.

It is an object of the present invention to provide an optical system drive device that is improved from the drawbacks mentioned above, and further to provide an optical system drive wire that has a long life and wear resistance. In order to achieve the object -1-, the present invention is characterized by using a 4J''K poly-p-phenylene terephthalamide fiber for the optical system driving wire.

The poly-p-phenylene terephthalamide fiber, which is the material of the optical drive wire of the present invention, is synthesized by a general low-temperature solution polycondensation method using p-phenylenediamine and terephthalic acid dichloride using an amide solvent. For dimethylacetamide, hegisamethylphosphoramide or tetramethylurea and lithium chloride, etc. /'+%
The above solution is dissolved to form an otropic liquid crystal in an imatic state, and the solution in the liquid crystal state is wet- or dry-spun and hot-stretched to a tension height of 11111.

On the other hand, in order to make poly-p-phenylene terephthalamide fibers into wires, /~sdenyl fibers are combined with 7
000 to 10,000 denier and then covered with a braided cord made of polyester fiber.

When the wire of the present invention is used as an optical system drive wire, it is necessary to change it to some extent depending on the load of the device, but in general, p-phenylene terephthalamide fibers are combined with /S00 to N000 denier, It is suitable to cover this with a braided cord of polyester fiber and make the outer diameter O3~/Kida.

According to the above-described optical system drive wire of the present invention, in addition to extending the life of the wire, it is possible to obtain improvements such as reducing drive shake of the device and improving image quality, thereby achieving the object of the present invention.

Hereinafter, a comparison will be made between the wire of the present invention and a conventional steel wire using reference examples.

Reference example/ Outer diameter o of 00 denier poly-p-phenylene terephthalamide fiber covered with polyester fiber braid,
Inventive wire of g mm s and outer diameter 0, / m
M96 5US30Il-WPB configuration 7 x 7
Iron-coated outer diameter 10 +nm i
A constant speed tension type tensile test is performed using a conventional steel wire. The results are shown in Table-/.

Table-/

[Brief explanation of the drawing]

Claims (2)

[Claims] (1) Poly-p- is attached to the optical system drive wire inside the copying machine.
An electronic copying device characterized by using phenylene terephthalamide fiber. (2) The electronic copying bag according to claim 1, wherein the polyester braid contains the (2) All Revo IJ-T)-phenylene terephthalamide fibers.