JPS62108233A - Safety device for light emission of copying device - Google Patents

Abstract

PURPOSE:To prevent inadvertent emission of light with a copying device by disposing a photodetecting element near a light emitting part and prohibiting the emission of light by a flash lamp in the case of detecting the incidence of light by said element. CONSTITUTION:The charge charged in a capacitor C1 is held discharged via a resistor R1 while a switch SW1 is off. The capacitor C1 is charged to the voltage approximately equal to V1 when the SW1 is turned on. A closed circuit of V2-SW1' (interlocked to SW1)-TR1 is formed and the switching transistor TR2 turns off if there is the incident light on a photodiode TR1; therefore, the trigger voltage is not generated and the emission of the light by the flash lamp 15 is prohibited even if a switch SW2 for trigger generation is turned on. The emission of light is, therefore, obviated even if the exposing surface of the copying device 1 is directed to the direction of the other person in a room or SW2 is inadvertently turned on.

Description

[Detailed description of the invention] Technical field The present invention relates to a light emission safety device in a copying machine.

Conventional technology (i): Electrophotographic copying machines, represented by the Carlson system, are widely used, but they are large, heavy, noisy, and expensive. It is not suitable for lowering prices, etc. In addition, even if the material to be transferred is designated paper or general plain paper is possible, if it is sheet-like and has folds or missing parts, problems will occur mainly in paper transportation, and booklets such as notebooks and notebooks will It was not possible to obtain a copy of the original, and attempts were made to cut and paste it, but this had the disadvantages of being unsightly and increasing the thickness.

(■) In addition, a small copying device for plate making and printing using a flash bulb has been proposed, but in most cases the amount required to obtain copies is one or a few, and the cost of clothes, bulbs, etc. Including the cost of lamps, etc., the unit cost of copying becomes extremely expensive, which is not practical. Furthermore, many of these plate-making and printing machines have the disadvantage that, due to their structure, the original must be in the form of a sheet or a single-sided original.

Furthermore, in recent years, small digital copying machines that use a document reader and a recording printer have been proposed, but in order to maintain a high level of image quality, the pixels must be made extremely fine. However, it has become expensive.

- Copying machines have been widely used as office machines, but they are all installed on the floor, on a desk, or on a special stand, and when you want to make copies, you have to put the copying machine down. I had to go somewhere.

In view of the above-mentioned circumstances, the present applicant first proposed a device that can be easily carried around and can be stored in a bag or pocket. We have proposed a portable copying machine that is small, very inexpensive compared to conventional copying machines, and has high quality copied images.

FIG. 3 is a partially cutaway perspective view for explaining an example of a portable copying device previously proposed by the present applicant. In the figure, 1 is a portable copying device; From the top of the device, there is an electrical control section 2 with electronic components built on a board, an operation section 3 such as an indicator lamp and a switch, a charging section 4 mainly consisting of a capacitor that stores the flash lamp's emitted energy, and a flash lamp 51. , a light emitting section 5 consisting of a reflecting plate 52 and the like. A translucent platen plate 61 that brings the original and copy sheet into close contact. Transparent platen portions 6 and the like made of transparent buffer members 62 and the like are arranged in a substantially laminated manner.

FIG. 4 is a side sectional view showing an example of a transfer sheet suitable for use in the portable copying device, and FIG. 5 is a partially exploded perspective view. In the figure, 7 is a transfer sheet; is a wavelength-selective transparent and heat-melting material in which coloring agents such as dyes and pigments are dispersed on a transparent plastic film 71 which is an intermediate transfer member, and a base 72 similar to the transparent plastic film 71. It consists of an ink film 74 provided with a wax layer 73 in close contact with it, and a frame 75 is used as necessary.

Examples of the plastic film include polyethylene, polyethylene terephthalate, polypropylene, polyvinyl chloride, polyvinylidene chloride, nylon, etc.
As for the wax, it is Hitsuwa.

Candelilla wax, carnauba wax, montan wax, etc., as well as paraffins, low-molecular synthetic resins, etc. can be used. In addition, as an extreme example, a glass plate several meters thick can be used as the intermediate transfer body, but the thickness of the film may vary depending on practicality (operability).

10 to 200 μm and even 40 to 60 μm in terms of cost, etc.)
A plastic film of about μm size is used. Since the ink film base is used as a heat transfer layer during copying, a thin layer is preferable; if it becomes thick, not only high energy is required, but also the sharpness of the image deteriorates. Practically speaking, a thickness of 3 to 6 μm is used including the production of the ink film. If the ink film wax layer is thin, it will not be possible to obtain a sufficient image, and if it is too thick, the transmittance will be poor, high energy will be required, and "bleeding" will occur easily.
2 to 6 μm is suitable. As a light source, a halogen lamp, a tungsten lamp, etc. can also be used. However, since the shorter the heating time of the wax layer, the sharpness of the image is maintained, flash exposure using a high-output xenon lamp for a short time (e.g., light emission time of 2 to 3 m5 ec or less) is desirable. If the heating time is too long, the heat will be transmitted to parts of the document that do not correspond to the printed lines, resulting in poor sharpness. However, halogen lamps, tungsten lamps, etc. have the advantage of simplifying the electrical system.

FIG. 6 is a diagram for explaining a copying method when information (image area 81) on a document 8 is copied using the copying device 1 and the transfer sheet 7. The copy sheets 7 are stacked on top of each other with the ink film side facing the original, and the copy bag @1 is placed thereon so that the platen portion 6 is in close contact with the copy sheets 7. The copying apparatus 1 is connected to a commercial 100V power source or a charging battery, and the flash charging capacitor is charged to a preset potential level.

The platen, the copy sheet, and the original are uniformly pressed against the surface of the copy sheet by the weight of the device 1 and the pressure applied through the device 1. When the flash lamp trigger switch is turned on in this state, the fufunyu lamp emits light and the original is exposed to light through the platen and the copy sheet. At this time, some of the light is also absorbed by the copy sheet, especially the ink film wax layer, and generates heat, which is used as a thermal bias. The image area 81 on the document generates heat due to light absorption, and this heat is transmitted to the wax layer through the base of the ink film and melts the wax. The melted wax is transferred to the intermediate transfer body 7
When the device 1 is removed and both films 71 and 72 of the transfer sheet are peeled off, a wax image corresponding to the image area of the original is obtained on the intermediate transfer member 71. This image is a normal image when viewed from the intermediate transfer body side, and this film may be used as a copy image as it is, or may be pasted on a notebook or the like as necessary. The energy of light emission varies depending on the spectral characteristics of the platen, copy sheet, etc., and the light emission characteristics of the lamp, but it also varies depending on the type of original. For example, it is low in the case of line images using pigments such as carbon or long wavelength absorption colors. Energy is sufficient, but high energy is required for dye-based colorants and long-wavelength reflective colors. Furthermore, if more energy than necessary is applied, the periphery of the image may melt, resulting in poor sharpness, or the wax may flow due to surface tension, causing hollow spots in the image. Therefore, the charging energy for light emission is, for example, 0.8 to 2.
It is variable within a range of 5 Joule/cJ. Furthermore, since the image on the intermediate transfer member obtained is heat-fusible, it can also be thermally transferred to notebooks, notebooks, cloth, etc. using an iron or other heat source. There is no problem with transferring to materials that can be impregnated with molten wax, such as paper and cloth, but when transferring to glass plates, plastic films, etc., heat and pressure with an iron, hot roller, etc. will cause the molten wax to transfer to the intermediate transfer. It leaks between the body and the transferred body and bleeds into the image. In such a case, flash exposure is still effective, and it is sufficient to stack the intermediate transfer bodies so that the ink image faces the side of the transferred body, place the device 1 in the same manner as above, and emit light while applying pressure.

However, in this case, since heat generation due to light absorption of the wax layer itself is utilized, the heating rate is, for example, 1.5 to 2
Requires twice as much energy.

Purpose The present invention is a further improvement of the above-mentioned portable copying device,
In particular, the present invention has been made with the aim of preventing inadvertent light emission in the portable copying device described above, but the present invention can be applied not only to the portable copying device described above but also to ordinary copying devices. This will be easily understood from the explanation below.

Structure In order to achieve the above object, the present invention provides a copying apparatus that uses a flash lamp as an exposure light source, in which a photodetecting element is disposed near the exposure part or the light emitting part, and the incident light is detected by the element. This feature is characterized in that the flash lamp does not emit light when the camera is in use. Hereinafter, the present invention will be explained based on examples.

FIG. 1 is a main part configuration diagram for explaining one embodiment of the present invention. In the figure, 11 and 12 are side plates, 63 is a light shielding plate, 64 is a photodiode, and 65 is a cover for the photodiode 64. Other parts having the same functions as those in the copying machine shown in FIG. 3 are given the same reference numerals as in FIG. Therefore, in this embodiment, a photodetecting element (photodiode) 64 is attached to the inner side of the reflecting plate 52 of the light emitting part 5, and this photodetecting element may be attached at a location other than the location shown in the figure. Any part may be used as long as it is in the vicinity of the light emitting part to the platen part and that external light, for example, indoor light, is blocked when the copying apparatus 1 is pressed against the surface to be exposed. In the illustrated example, if the light is directly incident on the photodiode 64 when the flash is emitted, it will be damaged, so a cover 65 is provided to prevent the flash light from directly entering the photodiode 64.

FIG. 2 is a diagram showing an example of an electric circuit used in a copying machine using the photodetector element 64 (T Ro). When the switch SW1 is OFF, the charge stored in the capacitor C1 is transferred to the resistor. It is discharged through R8. Here, when SWl is turned on, the capacitor C1 becomes approximately V,
charged to a voltage equal to . Now photodiode TR
When there is incident light at Even if it is turned on, no trigger voltage is generated and the flash lamp 51 does not emit light. Therefore, even if the exposure surface of the copying device 1 is directed toward another person indoors, or if SW2 is inadvertently turned ON, no light will be emitted. Next, when the copying device 1 is placed 14 on the surface to be exposed and pressurized from above, no light is incident on the photodiode TR at this time, so the potential of v2 is added to the base of the switching transistor TR. It is being Here, when switch SW2 is turned on.

A high voltage is generated in the trigger circuit by the inductance L and the capacitor C2, the inside of the flash lamp 51 is excited, and the charging energy of the capacitor C□ is discharged within the flash lamp 51.

It should be noted that the circuit shown in FIG. 2 is a simplified one, and it will be easily understood that circuits for circuit protection, matching, control, etc. may be added and used.

Effects As is clear from the above explanation, according to the present invention, it is possible to prevent the flash lamp from emitting light inadvertently and to prevent unnecessary light emission, and also to block indoor light. Therefore, conversely, there is no leakage of light to the outside when the flash is turned on, and an adverse effect on the surroundings can be prevented.

[Brief explanation of drawings]

FIG. 1 is a block diagram of main parts for explaining one embodiment of the present invention, FIG. 2 is a diagram showing an example of an electric circuit used for carrying out the present invention, and FIG. FIG. 4 is a partially cutaway perspective view for explaining an example of the previously proposed portable copying device; FIG. 4 is a side sectional view showing an example of a transfer sheet; FIG. 5 is a partially exploded perspective view of a copying sheet; FIG. 6 is a diagram for explaining how to use a copying apparatus to which the present invention is applied. DESCRIPTION OF SYMBOLS 1... Copying device, 2... Electrical control section, 3... Operating section, 4... Charging section, 5... Light emitting section, 6... Platen section, 7... Transfer sheet, 8...Manuscript, 11.12
...Side plate, 51...Light emitting lamp, 52...Reflector plate, 61...Platen plate. 62... Buffer member, 63... Light shielding plate, 64 (TR,
)...Phototransistor. Patent applicant Ricoh Co., Ltd. = 1 Figure 3

Claims (1)

[Claims] In a copying apparatus that uses a flash lamp as a light source for exposure, a light detection element is disposed near the exposure part or the light emitting part, and if the element detects the incidence of light, the flash lamp does not emit light. A light emission safety device for a copying machine, characterized in that: