JPS603673A - Blank exposing device of copying machine - Google Patents

Abstract

PURPOSE:To execute mechanically an opening and closing operation, to consume no electric power and simplify a constitution by constituting so that an arm of an original platen contacts by pressing to a sliding member as the original platen moves, and a blank exposing shutter interlocked with the sliding member is opened and closed. CONSTITUTION:A sliding arm 16 is provided so as to be slidable to the left and right since dowels 17, 18 are fitted into long holes 16a, 16b. A blank exposing shutter 7 is supported so as to be freely rotatable by a shaft 8, and a pin 7d is fitted to a long hole 16e of the arm 16. Accordingly, when an original platen moves to the right, an arm 20 of the original platen presses a projecting part 16c of the sliding arm 16, moves the arm 16 to the right, rotates the shutter 7 clockwise, and moves it to an original scanning plate 7a. On the contrary, when the original platen moves to the left, the shutter 7 is moved to a blank exposing state 7b state of a chain line. Therefore, opening and closing of the shutter 7 are executed mechanically, no electric power is consumed, and the constitution is simplified.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a blank exposure device for a copying machine that erases charges on a photosensitive drum during backward movement of a scanning optical system of the copying machine.

Conventionally, a blank exposure device of a copying machine electrically detects the operation of a scanning optical system using a microswitch or the like, and performs blank exposure by opening and closing an exposure shutter or blinking a lamp in accordance with this electrical signal. This is the first
This will be explained in the figure.

In Figure 1, / is a photosensitive drum, / is a document platen glass,
3 is a document, q is an illumination lamp, Shio is a reflective shade, and O is a small-diameter imaging element array in which bar lenses and the like are arranged in a line. 7′
is a blank exposure shutter that can be rotated around axis g'. Reference numeral 7 designates a plunger of a solenoid 9', which is hooked through a member 10 to sequentially operate the blank exposure shutter 7' into a normal image scanning state 71a and a blank exposure state 7'b. // is engaged with the shaft /2 fixed to the main body by a spring, and the blank exposure printer 7' is in the blank exposure state when the solenoid solenoid is not energized. Keep it at 'b. /3. /
'I is a microswitch, /3 detects the end of image scanning of the document platen glass λ that reciprocates in the direction a in the figure, /4'
detects when image scanning starts.

When scanning an original, the original table glass moves to the right in the figure and the switch 'f-iy' is turned on. This signal controls the control circuit/S.
turns on the solenoid 9 and moves the blank exposure shutter 7' to the right.
f+” state (7′ B state).

Then, the light image of the document 3 illuminated by the light source Lampke passes through the small-diameter imaging element row B and reaches the top of the photosensitive drum, where it is image exposed. In this state, the document table glass moves to the left and scans. When scanning the original, the original glass moves to the left and the switch /3 is pressed.
When turned on, the control circuit/S turns off the power to the solenoid 9', and the blank exposure shutter 7' closes 11.
state (state 7'b). Then, the light from the light source q hits the white reflective surface 7/c of the blank exposure shutter 7', passes through the small-diameter imaging element array B, and reaches the photosensitive drum/, and the photosensitive drum/ is subjected to blank exposure. This blank exposure is continued until the document table glass moves back and the switch /l is turned on again.

Such a conventional example has the drawback that it consumes electric power to operate the plunger of the solenoid during the copying operation, and also requires electrical components such as a microswitch and a control circuit, resulting in a complicated configuration.

The present invention has been made in view of the above-mentioned points and to eliminate the above-mentioned drawbacks.The present invention is a simple method that does not consume electric power and only mechanically opens and closes the blank exposure shutter on the optical path of the imaging lens for blank exposure. An object of the present invention is to provide a blank exposure device for a copying machine having a configuration.

Embodiments of a blank exposure device for a copying machine according to the present invention will be described below with reference to the drawings. Figure Ω is a diagram showing the first embodiment of the present invention, and the configuration of the members indicated by the symbols
This has already been explained in the figure, so it will be omitted. /B is a sliding arm that has a surface parallel to the paper surface and extends in the left and right direction.
Both ends are protrusions bent in the same direction perpendicular to the surface.
A'c.

/Otsu d, and horizontally elongated long hole /Otsu a
, /has a. /7.1g is a dowel fixed to the main machine frame 2/ (not shown), and the sliding arm /7.
, /g, and b, respectively. 7A/g (D□F,,
,,□□,-11,).

Reference numeral 7 denotes a holding member for holding the last Ω of the document table, and an arm 2q is provided near the center of this holding member. This arm 20 is configured so that when the document table moves to the right or left, it comes into contact with and pushes the protrusions of the sliding arm/Ot C and/Ot d, respectively. Reference numeral 7 designates a blank exposure shutter, which is bent so as to have a bent portion in the arrangement direction of the small-diameter imaging element array B, that is, in a direction perpendicular to and parallel to the plane of the paper, and one of the bent portions has a white reflective surface 7C. A protrusion 7e having a surface perpendicular to the surface of this portion and parallel to the plane of the paper is provided at the end of the bent portion that does not have the white reflective surface 7c. A hole is provided in this projection 7e, and a shaft g fixed to the main machine frame 2/ is fitted into this hole. As a result, the blank exposure shutter 7 is rotated about the shaft.
is rotatable (・).A pin 7 is attached to the end of the bent portion of the blank exposure shutter 7 in a direction perpendicular to the plane of the paper.
d is provided, and this pin 7e passes through a vertically long notch e provided at the center of the sliding arm e.

Next, the operation of this embodiment will be explained. The copy command assistant document table glass is at the home position above the frame 2/ of the main machine, and at this time the blank exposure shutter 7 is at the blank exposure state 7b. Next, in response to a copy command, the photosensitive drum / starts rotating in the direction of the arrow shown in the figure, and at the same time, the illumination lamp is turned on, and the light from this is reflected on the white reflective surface 7C of the blank exposure shutter 7, and then the small diameter The photosensitive drum passes through the image element array B and is exposed to blank light during forward rotation. In this state, the document table glass unit moves rightward from the home position together with the arm 20. As a result, the arm 20 comes into contact with the protrusion/B, pushes the protrusion/B, and moves the sliding arm/B to the right. As a result, the blank exposure shutter 7 is moved to the right by the elongated hole that moves to the right, and therefore the blank exposure shutter 7 rotates clockwise around the axis g.
As shown in the figure, this white reflective surface 7C is retracted out of the optical path of the small-diameter imaging element array B, and the blank exposure shutter 7 is placed in the normal document scanning state 7a. From this state, when the document table glass moves to the left to scan the document, the engagement between the protrusion C and the arm 20 is released, and the blank exposure shutter 7 is maintained in the normal document scanning state 7a. In this state, the light from the illumination lamp is reflected 1'A4 by the document 3 and passes through the small-diameter imaging element array B to the photosensitive drum/
An image is formed on the photosensitive drum and the original is scanned and exposed.

When the scanning of the original is completed, the arm 20 and the protrusion d come into contact with each other, and the protrusion d is pushed to move the sliding arm d to the left. As a result, the pin 7d is moved to the left by the elongated hole/e which moves to the left.
The blank exposure printer 7 rotates counterclockwise around the axis g, and the white reflective surface 7C is aligned with the small diameter imaging element array 6.
The blank exposure shutter 7 is located at the position of the blank exposure state 7b located above. As a result, the photosensitive drum is again subjected to blank exposure. When this state is reached, the document glass λ moves to the right again to return to the home position to finish the copying operation, but at this time, the contact between the arm 20 and the protrusion/B d The blank exposed shirt tough is allowed to remain in this state. In addition, the movement of the document glass from the right side edge to the left side edge is defined as the direction of movement of the document glass glass of the pin 7d necessary for opening and closing the blank exposure shutter 7. If the amount of movement in the same direction is S, the width of the arm 20 is l, and the minimum distance between the protrusions /C and /D is L, then L=Lo+
It will be understood that it is sufficient to set it so that it becomes J-8.

FIG. 3 shows a second embodiment of a blank exposure device for a copying machine according to the present invention. 1. Members with the same reference numerals in FIG. 1 and FIG. 2g is a sliding arm, which has horizontal elongated holes 211h and 2'1l-b on both sides, and a protrusion bent at right angles in the middle, 24t (1
It is capable of sliding in the left and right direction. Further, 1, 211c is a vertically elongated hole provided in the sliding arm 2g between the elongated hole/7°7g, and the pin 7d of the blank exposure shirt tough passes through it. Reference numerals 22 and 23 denote arms provided at both left and right ends of the holding member/9, and when the holding member 79 moves to the right or left together with the document table glass, it comes into contact with the protrusion 2Ild and presses the protrusion. This is for moving the sliding arm 2g to the right or left.

By moving the original platen platen to the right from the home position, the arm 22 moves to the protrusion,! lld and pushes the protrusion 2.1I-d to the right, so the sliding arm 2
11. moves to the right, and the blank exposure shutter 7 rotates clockwise about the shaft, shifting from the blank exposure state 7b to the normal original scanning state 7a as shown in the figure. Next, when the document table glass moves to the left to scan the document, the arm 22 and the protrusion 2 q d come out of contact and the blank exposure shutter 7 is maintained in this state. When scanning the original, the arm 23 comes into contact with the protrusion 211d and pushes the protrusion 211d to the left, causing the sliding arm 2g to slide to the left, so that the blank exposure shutter 7 is in the blank exposure state 7b. Move to. After this, the document table glass returns to the Baum position.

In the above embodiment, the blank exposure shutter 7 is rotated to selectively guide the light from the original or the reflected light from the light source Lampke, but as a third embodiment, the blank exposure shutter 7 shown in FIG. It is also possible to fix the shutter plate 2k having the same configuration as the protrusion 7e of the exposure shutter 7 on the sliding arm 2'l of the apparatus shown in FIG. 3 as shown in FIG.

In FIG. 9, 25 is a sliding arm, a shutter surface fixed on 24, and 25 & are white reflective surfaces as in the previous embodiment. Further, the arm 211 reciprocates in the left-right direction to selectively guide reflected light from the original 3 or reflected light from a light source lamp (not shown) to the small-diameter imaging element array B.

In the present invention, the following advantages were obtained by configuring the blank exposure device as described above to mechanically open and close the shutter as the scanning optical system reciprocates.

(11 The above objectives are achieved with a simple configuration by reducing the number of parts.

(2) Does not consume electricity.

(3) By providing abutment members at both ends of the moving document table as in the first embodiment of the present invention, the structure can be made smaller.

[Brief explanation of the drawing]

FIG. 7 is an explanatory diagram of a conventional example, and FIGS. Ω to 7 are explanatory diagrams of each embodiment of an exposure apparatus for a copying machine according to the present invention. / is the photosensitive drum, 2 is the original table glass, and 3 is the original. G is an illumination lamp, B is a small-diameter imaging element array, '7. , 25 is the blank exposure shutter, '7 (1 is the pin, 7c., 25a is the white reflective surface 9g is the shaft, /7.1g is the dowel. 2/ is the main machine, 20.22.23 is the arm. /Otsu, 2g is the sliding arm, /Otsu a, /Otsusu, /Otsu8.2
``la,, 21Ib, 2'lc is a long hole, /Otsu C1/
d9.2 d is a protrusion.

Claims (1)

[Claims] It opens and closes the optical path of the reading optical system that reads the original on the moving original table for scanning the original, and when the reading optical system is closed, it reflects the light from the illumination lamp that illuminates the original onto the photoreceptor. In a copying machine equipped with a blank exposure shutter that performs blank exposure, an arm provided on the document table and a slidable member that slides in the direction of movement of the document table when it comes into contact with the arm. A copying machine comprising a member, wherein the arm contacts the sliding member as the document table moves, and by pushing the arm, opens and closes the blank exposure shutter that is interlocked with the sliding member. blank exposure equipment.