JPH0422504B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a scanning exposure type image forming apparatus using a silver halide photographic material.

(Prior Art) Conventionally, there have been the following representative examples of methods and devices for obtaining duplicate images (copies) of documents, drawings, etc. First, electrophotographic equipment is very small and efficient for producing single-color copies, but in order to reproduce color originals, color separation filters such as blue, green, and red are used to expose the photoreceptor. The latent image formed thereon is developed using color toners such as yellow, magenta, cyan, etc., and each color is transferred onto the recording paper, and the same process must be repeated for each color on the same recording paper. The equipment becomes very large and repeatability is required, but
This was difficult and caused color shift, making it difficult to reproduce high-quality clear images.

On the other hand, copying apparatuses using silver halide photographic light-sensitive materials use a full-surface exposure method that simultaneously exposes the entire apparatus at once, and therefore the optical system occupies a large space, making the entire apparatus large and requiring a large installation space. A large light source capable of uniform irradiation was required, and it was extremely difficult to find a way to keep the entire surface of the photosensitive material flat.

In addition, in JP-A-59-204042, the image exposure beam scans the entire surface of the photosensitive material that is stationary, but like the simultaneous exposure of the entire surface, the exposure device is complicated and large, making it difficult to maintain the flatness of the surface of the photosensitive material. I was in a difficult situation.

(Problems to be Solved by the Invention) In order to solve these problems, it is conceivable to use a scanning type exposure device as the exposure device and downsize the entire device by downsizing the exposure optical system. .

By the way, in scanning exposure, or in other words, slit exposure, image exposure is performed through a narrow slit, so if the photosensitive material at the exposure position vibrates as it moves, or if there is a fluctuation in the moving speed,
A change in exposure amount results in a change in image density, and band-like density unevenness occurs in the longitudinal direction of the slit.

In particular, in copying machines that use silver halide photographic light-sensitive materials that have excellent image reproducibility and are capable of reproducing delicate halftones, the light-sensitive material during exposure may vibrate due to the influence of the conveyance means, or the conveyance means may be uneven. If this happens, exposure unevenness becomes noticeable.

SUMMARY OF THE INVENTION An object of the present invention is to solve this problem and provide a scanning exposure type image forming apparatus that is compact and capable of producing high-quality copied images without density unevenness.

(Means for Solving the Problems) The above object is to transport the silver halide photographic light-sensitive material sent from the feeding section to the exposure section, scan and expose it while being transported by a transportation means provided in the exposure section, Control is performed to keep the other conveyance means in a non-energized state so that the conveyance force of the conveyance means other than the conveyance means provided in the exposure section is not applied to the silver halide photographic light-sensitive material during scanning exposure. This is achieved by a scanning exposure type image forming apparatus characterized by the following.

(Examples) Examples of the present invention will be described in detail below, but the present invention is not limited to these embodiments.

FIG. 1 is a schematic cross-sectional view showing an embodiment of a scanning exposure type image forming apparatus that implements a scanning exposure type image forming method according to the present invention.

The copy image forming apparatus main body 1 includes an image exposure section 3, a paper feed section 11, a conveyance section 13, a photo processing section 24, and a drying section 30.

The image exposure section 3 includes a light source 4, a first scanning mirror 5, a second scanning mirror 6, a third scanning mirror 7, a lens 8,
It consists of a fourth fixed mirror 9 and a fifth fixed mirror 10. The light source 4 is provided with a slit, and a light source with no uneven light distribution particularly in the axial direction is preferably used. In this example, a rod-shaped halogen lamp (200 W) with a slit width of 10 mm is used, and a ground glass is provided on the light exit surface to eliminate uneven light distribution.

The light source 4 and the first scanning mirror 5 move together in parallel to the document surface 2 and illuminate the document. The second scanning mirror 6 and the scanning mirror 7 shown in FIG. 3 move in the same direction as the first scanning mirror 5 and at half the moving speed of the first scanning mirror 5.

The light source 4, the first scanning mirror 5, the second scanning mirror 6, the third scanning mirror 7, and the photosensitive material conveying rollers 20, 20', 21, 21', which will be described later, operate in synchronization. The synchronous operation can be performed by a known synchronization mechanism widely used in electrophotographic copying machines and the like.

An original image (not shown) placed on a transparent platen glass 2 is slit-exposed by a light source 4, and as the light source 4 scans, light reflected from the original screen, that is, a light image, is reflected by a first scanning mirror 5, The exposure opening 2
3, the silver halide photographic material 12, which is moving in synchronization with the scanning movement of the light source 4, is sequentially exposed.
In this embodiment, the scanning speed of the light source 4 is 60 mm/sec.

Note that this copying apparatus is capable of performing variable-magnification copying. That is, when the lens 8 and the fourth and fifth fixed mirrors 9 and 10 are in the position shown by the solid line, it is the state in which the same-magnification copying is performed, and the lens 8 is in the position shown by 8a.
When it is at the position indicated by 8b, it is an enlarged copy, and when it is at the position indicated by 8b, it is a reduced copy.

Then, in order to correct the displacement of the imaging position due to the movement of the lens 8 to the above-mentioned position, the fourth and fifth fixed mirrors are integrally moved to the dotted line position indicated by 9a. In this way, a light image corresponding to the original image is exposed onto the silver halide photographic material 12.

On the other hand, the silver halide photographic material 12 is formed into a roll and is housed in a dark box 12'. Silver halide photographic material 12 pulled out from dark box 12'
is conveyed within the conveying section 13 by a series of roller pairs 14, 14' to 21, 21' that rotate under pressure.
By the way, the silver halide photographic material 12, which has hitherto been in the form of a roll, is cut into a desired size by a cutting member 22 provided in the conveyance path. Therefore, after being cut, the silver halide photographic material 12 is conveyed in the form of a sheet. The cutting member 22 may be one in which a cutter blade cuts the silver halide photographic material 12 while moving in the width direction, or one in which the cutter blade descends horizontally with respect to the silver halide photographic material 12. Items to be cut at once, etc.
Various materials may be mentioned, but there is no particular limitation as long as the material can cut the silver halide photographic material 12. Of course, the silver halide photographic material 12 may be in the form of a sheet instead of a roll. When a sheet-like material is used, the cutting member 22 does not need to be provided. Silver halide photographic material 1 cut in this way
2 is held between belts B and B' and sent slightly obliquely upward, and then changed direction almost at right angles at rollers 19 and 19', and then passes through rollers 20, 20', 21, and 2.
1', it is conveyed approximately vertically downward. Image exposure is then performed between the rollers 20, 20' and the rollers 21, 21'. Roller 20, 20', 2
1 and 21' rotate at a speed synchronized with the light source 4 and the first reflecting mirror 5, and transport the silver halide photographic material.

As is clear from the above explanation, the silver halide photographic material is transported in a direction almost along the document surface from the paper feed section to just before the exposure section;
It is rotated by 90° and is positioned at a position where it is fed almost perpendicularly to the surface of the document, that is, at the exposure aperture 23, and scanning image exposure is performed at this position.

The exposed silver halide photographic material 12 is then sent to the photographic processing section 24, where it is processed in each processing tank for a predetermined time, and then transferred to the drying section 30.
is sent to dry, and then discharged from the device.

The explanation will be continued below with reference to FIG. 2, which is an enlarged view of the main part of FIG. 1.

As mentioned above, when a roll-shaped photosensitive material is used instead of a sheet-shaped photosensitive material from the beginning, the web is cut into a desired size by the cutting member 22 while the rolled web is being pulled out. The photosensitive material is then cut into sheet-like sheets and is sequentially conveyed to an exposure position. To simplify the mechanism, the web is cut while the web is being cut by stopping the conveyance of the web, so if an integrated conveyance means is used, the photosensitive material that has been cut into a sheet will first cut the exposed area. Once the sheet has passed, the next sheet cannot be pulled out, so conveyance is restarted after a considerable delay from the preceding sheet of photosensitive material, resulting in a longer processing time interval. In order to avoid this and increase capacity, this conveying means is roughly divided into two parts, and conveys it toward the exposure position 40. A first conveying means which holds the belts B and B' stretched between each other and conveys the photosensitive material between them; Roller pair 2 for conveying the photosensitive material at 40
A second conveying means is provided in the exposure section consisting of 0, 20' and 21, 21'.

Further, the conveyor belt and roller 1 stretched between rollers 14 and 15 provided upstream of the first conveyor means
4' and 15', and a pair of rollers 16, 16' and 17, 1.
Reference numeral 7' denotes a conveying member for pulling out the photosensitive material web from the photosensitive material roll 12 and feeding the web to the first conveying means, and is driven at approximately the same circumferential speed.

It is pulled out from the photosensitive material roll 12 by a length corresponding to a predetermined size, and its leading end is held by the first conveying means, and the drive is released by the time it reaches a predetermined position. The one whose drive is released is one of the upper and lower conveyor mechanisms, for example, the upper conveyor mechanism, that is, the belt B stretched between rollers 18 and 192, the belt stretched between rollers 14 and 15,
This is done by lifting and pulling the rollers 16 and 17 from the lower transport mechanism, respectively.

The mechanism is shown in the side view of FIG. 3 and the perspective view of FIG. 4, and will be explained here. A conveyor belt made of rollers 18, 19 and a belt placed between them is attached to frames 42a, 42.
b, and constitutes an upper conveyance unit, the upper conveyance unit push-up pin 43 is attached to the frame 42, and the upper conveyance unit rotation shaft 41 is attached to the frame 42.
a and 41b are provided.

When receiving the conveyance stop signal, the solenoid coil 48
is energized, moves the mover 47 in the direction of arrow A, and the upper transport unit push-up lever 44 rotates around the lever rotation shaft 45 in the direction of arrow C, pushing up the pin 43 and pushing up the upper transport unit, which also moves the rollers 18 and 19. By rotating around the rotation axes 41a and 41b, it is turned in the direction of arrow D, and is completely cut off from the lower conveyance section. In this way, conveyance of the web is stopped.

On the other hand, when receiving a signal and restarting the conveyance, the solenoid is de-energized, so the mover 47
becomes free, and the upper conveyance unit inevitably overlaps the lower conveyance unit, returning to the state of holding and conveying the photosensitive material.

As a result, the conveyance of the photosensitive material sheet at the exposure position 40 is not affected by the first conveying means, and during scanning exposure, the photosensitive material sheet is conveyed only by the driving force of the second conveying means. The vibrations exerted on the image forming apparatus are reduced, and the unevenness of the feeding speed is also reduced, so that unevenness in image density is almost eliminated.

The photosensitive material sheet is conveyed by a pair of rollers 20, 20' and 21, 21' of the second conveying means at a speed αv ₁ in which the exposure scanning speed is synchronized with the scanning exposure, and is transferred to the photographic processing section 24. Go. Here, v ₁ is the scanning speed of the light source, and α is the copying magnification.

On the other hand, the detector _S3 detects the moment when the trailing edge of the preceding photosensitive material sheet passes through the exit of the first conveyance means, thereby returning the conveyance means to a conveyable state. In response to this signal, the subsequent photosensitive material sheets that have been cut by the cutting member 22 before or after this are quickly cut at the leading edge of the photosensitive material sheet at a speed of v ₂ higher than αv ₁ so as to reduce the distance from the preceding photosensitive material. part is second
Until reaching the roller pair 20, 20' of the conveying means,
It is transported by the first transport means.

By using such a conveying means, it is possible to cut a sheet-like photosensitive material of a predetermined length from a roll-like photosensitive material, and the sheet is accurately image-formed and conveyed. Moreover, the processing time is shortened and the image efficiency is increased. A forming device is provided.

In the above embodiment, the rear end of the preceding photosensitive material sheet is the first
When the sheet passes through the exit of the conveying means, the conveying means is returned to the conveying state, but in order to save some time, in another embodiment, the rear end of the sheet is moved to the roller pair 20, 20' of the second conveying roller. There is a system in which the detection means _S1 detects that the first transport means has passed and causes the first transport means to return to the transport state, and as another embodiment, it detects that the scanning exposure has ended, that is, the first transport means returns to the transport state. One method is to detect the passage of the trailing edge of the sheet through the exposure position by the detection means _S1 or _S2 , and then detect the time from when it reaches the exposure position.
There is also a method in which d ₂ /αv ₁ or (d ₁ +d ₂ )/αv ₁ is added by a timer to cause the first conveying means to return to the conveying state. However, d ₁ is the distance between S ₁ and S ₂ , and d ₂ is the distance between the exposure position 40 and S ₁ .

Further, the clamp release means of the first conveyance means, that is, the conveyance release means is located at the position of the roller pair 20, 20' of the second conveyance means in order to detect that the leading edge of the sheet has reached the roller pair 20, 20'. An embodiment in which the detection means S ₁ is placed, and the detection means S ₂ is placed at a distance d ₁ on the upstream side, and after S ₂ detects the leading edge of the sheet.
There is an embodiment in which the time d ₁ /v ₂ is delayed by a timer, and then the clamping of the first conveyance means is released and the conveyance is stopped.

(Effects of the Invention) As in the present invention, scanning exposure is carried out on the silver halide photographic material while the silver halide photographic material is transported only by the transport means substantially provided in the exposure section, in other words, other transport means are used. Since the silver halide photographic material is transported without being affected by the means, it is possible to prevent the effects of uneven transport speed caused by vibration or other transport means, and therefore to reduce uneven image density. This has the effect of being able to form high-quality images with almost no blemishes.

[Brief explanation of drawings]

FIG. 1 shows one of the scanning exposure type image forming apparatuses of the present invention.
FIG. 2 is a schematic sectional view showing an embodiment, and FIG. 2 is a partially enlarged view of the main part thereof. FIG. 3 is a side view of the clamp release portion of the first conveyance means, and FIG. 4 is a perspective view of the upper conveyance unit push-up portion. 1... Copying device main body, 3... Image exposure section, 11
...Paper feeding section, 12...Silver halide photographic light-sensitive material, 13...Transportation section, 22...Cutting member, 40...
...Scanning exposure position, S ₁ ... Photosensitive material sheet leading and trailing edge detection device, S ₂ ... Photosensitive material sheet leading and trailing edge detection device, S ₃ ... Photosensitive material sheet trailing edge detection device, d ₁ ... S Film path length between ₁ and S ₂ , d ₂ ...S ₁
and the film path length between the exposure position 40, 41a, 4
1b... Upper transport unit rotation shaft, 42a, 42b
...Upper transfer unit side plate, 43...Upper transfer unit push-up pin, 44...Upper transfer unit push-up lever, 45...Lever rotation shaft, 46...Solenoid engagement pin, 47...Solenoid mover, 48... …
solenoid coil.

Claims (1)

[Scope of Claims] 1. A silver halide photographic light-sensitive material sent from a feeding section is conveyed to an exposure section, and is scanned and exposed while being conveyed by a conveying means provided in the exposure section, and a silver halide photographic material provided in the exposure section is The method is characterized in that the other conveying means is controlled to be kept non-energized so that the conveying force of the other conveying means is not applied to the silver halide photographic light-sensitive material during scanning exposure. Scanning exposure type image forming device.