EP0280628A1 - Original-reproduction apparatus using diazo copying - Google Patents

Abstract

The apparatus especially comprises means for entraining the original and the copy, exposure means in order to insolate the copy through the original in order to form a latent image on the copy and means for revealing the latent image carried by the said copy. The exposure means (102) comprise a light source (106) inside a substantially transparent cylindrical surface (2) of closed directrix and movably driven, the means for entraining the original and the copy are formed by a stationary belt (6) which cooperates with the cylindrical surface (2). The belt (6) is stretched between two attachment zones (7,8) and it encloses a portion of the cylindrical surface (2). The original and the copy are displaced under the effect of the movement between the cylindrical surface (2) and the belt (6). The means for revealing the latent image carried by the copy are means for putting the copy into contact with the product in order to reveal the latent image, these means being formed by at least one channel (22), the inner space of the channel (22) communicating with the face of the copy in contact with the belt (6) by means of at least one opening (26), the channel (22) being provided with means (27) for input and output of the said product. <IMAGE>

Description

The present invention relates to an apparatus for reproducing originals by diazocopying.

In the present text, for convenience, we will call "copy" the support sheet, of paper or polymeric film, coated with a sensitive diazo layer and "original" the sheet of paper or polymeric film, transparent or semi-transparent carrying the graph to reproduce.

Apparatuses for reproducing originals by diazocopy also called diazocopy apparatuses generally comprise at least one exposure station in which the copy is exposed through the original to form on the copy a latent image and a development station in which the copy carrying the latent image is brought into contact with a product to reveal the latent image so that the latent image becomes visible.

The product for revealing the latent image, also called development product, can be liquid or gaseous. In the present text we will refer more specifically to a development station using as product to reveal the latent image a gas made up of ammoniacal vapors.

An apparatus for reproducing originals by diazocopying has been proposed which includes both an exhibition area and a development area in the same station. In such an apparatus, the copy and the original travel together and superimposed throughout their journey in the apparatus, a path that envelops substantially the entire surface of the exposure cylinder.

The exposure zone of such a device is constituted by the transparent cylinder with which are associated rollers of axes parallel to the cylinder axis, one of the rollers being driven in rotation, the rollers are arranged in such a way that endless belts stretched around the rollers partially envelop the outer surface of the transparent cylinder. Inside the transparent cylinder in the vicinity of the area of the surface thereof enveloped by the belts are placed lamps and a reflector intended to reflect the radiation towards the exhibition area.

The development area of the device is formed by a box supplied with product to reveal the latent image, a wall of the box is concave, perforated and closely follows the surface of the transparent cylinder not wrapped by the endless belts. Inside the transparent cylinder in the vicinity of the surface enveloped by the porous wall of the box, that is to say on the back of the reflector is placed a heating resistor intended to improve the development of the latent image.

Of course, means for entering and leaving the original and the copy are provided.

In such a device the original and the copy are introduced and entrained between the exposure cylinder and the belts, the copy is exposed through the original in the exposure zone to form the latent image on the copy. The whole continues on its way in the development zone between the transparent cylinder and the perforated concave wall of the box, the product to reveal the latent image passes through the perforated wall to reach the copy, reveal the latent image and make it visible.

The original and the copy then exit the machine and are separated manually.

Such an embodiment of reproduction apparatus by diazocopy has drawbacks.

Indeed, many sealing problems arise at the level of the boxes and these diazocopy devices are often smelly.

To ensure the tightness of the box it is firstly necessary to provide a sealed construction thereof in particular at its end walls and on the other hand it is also necessary to provide seals on all around the perforated wall of the box, between the perforated wall and the transparent cylinder to avoid leaks.

In addition, as the volume of the box traversed by the ammonia vapors is relatively large and that, to improve the development efficiency, the speed of the vapors coming into contact with the sensitive layer must be high, large volumes of ammonia vapors are implemented which, on the one hand, increases the size of the diazocopy apparatus and, on the other hand, also increases the size of the means for supplying ammoniacal vapors, requires the treatment of a volume significant amount of unused vapor which also increases the size of the deodorization equipment.

In this type of device, the surface of the transparent cylinder enveloped by the porous wall of the box is relatively large, which decreases all the more the surface part of the transparent cylinder through which the exposure of the copy can be done through the 'original, which therefore penalizes the exposure phase of the copy. Thus with such a device in order to have good exposure conditions of the original it is necessary to increase both the diameter of the transparent cylinder and the power of the light source placed in the transparent cylinder. The increases in the diameter of the transparent cylinder and in the light power obviously increase, on the one hand, the space requirement and, on the other hand, the cost of the diazocopy apparatus.

An object of the invention is a device for reproducing originals by diazocopying of small dimensions in which the sealing problems are reduced.

Another object of the invention is a diazocopy device without odors and which uses only small volumes of product to reveal the latent image.

An apparatus for reproducing originals by diazocopying has now been found, comprising in particular means for driving the original and the copy, exposure means for exposing the copy through the original to form on the copy. a latent image and means for revealing the latent image carried by said copy, characterized in that the exposure means comprise a light source inside a cylindrical surface of closed director, substantially transparent, driven in movement, the means for driving the original and the copy consist of a fixed mat which cooperates with the cylindrical surface, the mat being stretched between two attachment zones, said mat enveloping part of the cylindrical surface, the original and the copy moving under the effect of movement between the cylindrical surface and the mat and that the means for revealing the latent image carried by the copy are means for bringing the copy into contact with the product for revealing the latent image, said means are formed by at least one channel , the interior space of the channel communicating with the face of the copy in contact with the carpet by means of at least one opening, said channel being provided with means for inlet and outlet of said product.

In the present text, we refer to the face of the carpet in contact with the copy or to the face of the copy in contact with the carpet. This means more generally that we refer to the face of the carpet located on the side of the copy.

According to one embodiment of the diazocopy apparatus according to the invention, the channel is located on the face of the mat not in contact with the copy, the interior space of the channel communicating with the face of the copy in contact with the mat at the through openings through the carpet.

The original and the copy run through the diazocopy machine. object of the invention, a common path, and being superimposed around the exposure means, the length of this path corresponds to the length of wrapping of the cylindrical surface by the mat counted between the generators of the first and last contact of the carpet and the cylindrical surface, we will call below this length of wrapping "arc of wrapping".

According to part of this path, the copy is exposed through the original to form the latent image, then the latent image is revealed when the copy is brought into contact with the product to reveal it.

The quality of the copy obtained depends on various parameters and in particular depends on the exposure of the copy through the original.

The insolation of the copy through the original depends on the power of the exposure lamps, the distance between the lamps and the original, the duration of the exposure, which for a given diazocopy machine is a function of the speed of movement of the original and of the superimposed copy, and of the contrast existing between the background of the original and the graph carried by it.

Thus, the position of the means for revealing the latent image along this path is not critical, the quality of the copy obtained being able to be adjusted by the operator by acting on the speed of movement of the original and the copy in the diazocopy machine.

However, preferably, the means for revealing the latent image are placed in such a way that the original and the superimposed copy have traveled at least 50% of their common path in the diazocopy machine, i.e. 50% of the arc of envelopment of the cylindrical surface by the carpet.

The exposure means of the diazocopying apparatus, according to the invention, comprise a substantially transparent cylindrical surface of closed director intended to envelop the light source, which can be constituted by one or more exposure lamps.

The cylindrical surface of the closed director can be formed by a substantially transparent endless band enveloping at least two rollers, the light source then being constituted by at least one exposure lamp placed inside the cylindrical surface. The rollers can of course be replaced by two exposure lamps.

The endless strip can be driven in movement by usual means, such as for example one of the rollers can be driven in rotation, a wheel with rotating pins can cooperate with holes located in the vicinity of the edges of the strip, or still the strip can be driven in movement by friction by means of rotating rollers.

Preferably, the closed director cylindrical surface of the exposure means is a circular director cylinder provided internally with a light source formed by at least one exposure lamp, we will call this embodiment "cylinder of exposure".

According to a variant of the diazocopy apparatus, object of the invention, the cylindrical surface and the light source can be formed directly by an exposure lamp.

A cylindrical surface formed by a strip can be produced from a film of transparent or substantially transparent polymer material, that is to say translucent, the strip can also be constituted by a translucent fabric for example a glass or glass fabric. polymeric material.

A cylindrical surface of circular director can be made of a transparent or translucent material such as glass or a plastic material, for example polycarbonate. The external surface of such a cylindrical surface may have undergone a chemical or physical treatment intended to modify its surface state, in order to increase the coefficient of friction of the cylindrical surface on the original and thus reduce the risks of slipping. of the original on it.

A cylindrical surface of circular director can be driven directly by a motor mounted on its axis, it can also be driven by a motor associated with a pinion mounted on its axis. According to another embodiment, the cylindrical surface of circular director can be driven by friction, for example by means of rollers driven in rotation and bearing on the surface. Preferably, a cylindrical surface of circular director driven in rotation by friction, is driven by means of at least one roller and advantageously by means of two rollers driven in rotation bearing on the surface in the vicinity of the inlet and the outlet. (case of two rollers) of the assembly formed by the copy and the original, the copy and the original being introduced into the diazocopy machine between the roller and the cylinder. These rollers are advantageously made of natural, artificial or synthetic rubber in order to have good adhesion to the cylindrical surface and to the copy.

According to one embodiment, the diazocopy apparatus comprises a channel and the opening or openings communicating the interior space of the channel with the face of the copy in contact with the mat form a strip placed substantially along a generatrix of the cylindrical surface. , the strip being such that its length is substantially equal to the useful width of the diazocopy apparatus and its width between 0.05 and 20% of the length of the arc of envelopment of the cylindrical surface by the carpet.

Preferably the width of the strip is between 0.1 and 15% of the length of the arc of envelopment of the cylindrical surface by the belt.

According to another embodiment, the diazocopy apparatus comprises several channels, and is such that the opening or openings communicating the interior space of a channel with the face of the copy in contact with the mat form bands placed substantially along a generatrix of the cylindrical surface, at each corresponding channel a strip, the strips being such that their length is substantially equal to the useful width of the diazocopy machine and the sum of their widths between 0.1 and 20% of the length of the arc of envelopment of the surface cylindrical by the mat.

Preferably the sum of the widths of the bands is between 0.2 and 15% of the arc of envelopment of the cylindrical surface by the belt.

Of course, the dimensions of the channel are substantially equal to the dimensions of the strip.

It goes without saying that the duration of the development of the latent image carried by the copy is not equal to the time taken by the latent image to cover the width of the band or bands formed by the opening (s) in effect the development of the latent image continues as long as the product to reveal the latent image is present in the copy and / or as products capable of reacting with it are present in the diazo layer.

The channel can be scanned by a product to reveal the latent liquid or gaseous image. For a diazocopy machine intended to use a liquid product, the opening or openings ensuring the communication between the interior space of the channel and the face of the copy in contact with the mat will have dimensions such that the face of the copy is wetted by the liquid without it dripping.

The channel can be by a fold of the carpet, the fold being located on the face of the carpet not in contact with the copy. Inside the fold, that is to say on the face of the carpet in contact with the copy, is inserted a hollow cylinder provided with at least one opening, for example a slot, placed substantially according to a generator, in such a way that the opening is located as close as possible to the cylindrical surface of the exposure means. The hollow cylinder thus forms a distributor ensuring a blade distribution of the product to reveal the latent image, the hollow cylinder being connected at its ends to means of entry and exit of the product to reveal the latent image.

The mat is preferably kept pinched on the hollow cylinder by means, for example, of a plurality of spring clips. It is preferably held on the hollow cylinder by means of a split tube made of elastic material ensuring a pinching effect substantially over the entire width of the mat.

The channel can be obtained directly with the carpet, that is to say be integral with the carpet, it can for example be obtained by extrusion if the carpet is made of plastic. It can also be produced by means of a strip, preferably preformed, secured to the periphery of the strip formed by the opening (s), for example by welding or gluing, and provided with product inlet and outlet pipes for reveal the latent image.

The channel can also be formed by an open section profile secured to the periphery of the strip formed by the opening (s), by gluing or welding to the mat, and provided at its ends with plugs traversed by the inlet and outlet pipes. of the product.

According to another embodiment, the channel may include, inside, a product distributor. Such a dispenser may be constituted by a hollow cylinder open at one end and closed at the other, provided with a slot along substantially a generator close to the strip formed by the opening or openings of the belt. The development product is brought to the open end of the dispenser and the unused product, collected by the channel leaves it through an opening provided for this purpose.

According to another embodiment of a diazocopy apparatus object of the invention, the channel includes a distributor, the distributor occupies substantially the entire interior space of the channel, said distributor having the shape of a hollow cylinder provided with at least one opening substantially along a generator and being held in place by a band, secured to the carpet to form the channel, so that the opening is located as close as possible to the band formed by the opening or openings of the carpet, said distributor being connected at its ends to inlet and outlet pipes of the product to reveal the latent image.

According to this embodiment, the strip can be formed from a fabric, for example glass, impregnated with a resin such as polytetrafluoroethylene, it can also be formed by an elastomer extruded into a profile of shape suitable for wrapping the distributor.

The strip can be secured to the carpet by gluing.

According to another embodiment, the diazocopy apparatus is such that the channel is constituted by a distributor having the shape of a hollow cylinder provided with at least one opening substantially along a generator, said distributor being provided with two fins located on either side of the opening to secure it to the mat, at the periphery of the strip formed by the opening (s), said dispenser being connected to the inlet and outlet pipes of the product to reveal the latent image .

According to another embodiment, the channel may include a gutter-forming zone situated at an altitude lower than the altitude of the strip provided with openings in the belt.

A channel according to this embodiment makes it possible to circulate a liquid product in the gutter, this liquid product generating vapors which passing through the carpet openings come into contact with the latent image.

Advantageously, the product for revealing the latent image is fed into the channel only when an original and a superimposed copy are introduced into the diazocopy apparatus. Thus, preferably, the diazocopy apparatus comprises means which, in response to the passage of the assembly, control the supply or the stopping of the supply of the product in the channel.

These means can be constituted by a contactor which, when activated by the front edge of the assembly, controls the supply of the product in the channel and when it is deactivated by the passage of the rear control edge, with a delay , stopping the feeding of the product in the channel.

Advantageously, the diazocopy apparatus includes means for degassing the copy downstream of the means for revealing the latent image with respect to the direction of movement of the copy.

Thus, the degassing means can be of a structure analogous to that of the means for bringing the copy into contact with the product to reveal the latent image. The degassing means of the copy can be constituted by an area of the carpet provided with through openings and suction means located in the vicinity of the area provided with openings, acting on the face of the carpet not in contact with the copy.

Preferably, a diazocopying apparatus intended to use a liquid product to reveal the latent image will comprise, between the channel and the degassing means, means for drying the copy generally constituted by heating means.

The suction means can be constituted by a box, a wall of which is provided with openings located in the vicinity of the zone provided with openings of the carpet, the depression being created for example by means of a fan.

According to another embodiment, the degassing means are constituted by an area of the carpet provided with through openings and by a box maintained in depression, the open area of said box being placed in the vicinity of the area provided with openings of the carpet, the walls of the box limiting the open area extending on either side of the area provided with openings substantially up to the face of the carpet not in contact with the copy.

According to another embodiment of the diazocopy apparatus, object of the invention, the suction means consist of a hollow cylinder, closed at at least one end and provided with an orifice intended to put the interior of the cylinder in depression, the cylinder wall being provided with at least one opening placed substantially according to a generator of the cylinder close to the zone provided with openings of the carpet

The orifice intended to put the interior of the cylinder in vacuum can be the opening located at one end of the cylinder connected to the suction side of a fan. The opening placed substantially along a generatrix of the cylinder may be a slit passing through the wall of the cylinder.

The cylinder can be made of any material, in particular plastic.

The diazocopy apparatus, object of the invention, may include means for recovering the unused product downstream from the means for bringing the copy into contact with the product to reveal the latent image, with respect to the direction of movement of the original and the copy.

The means for recovering the unused product can be constituted by collection means connected to suction means, acting on the face of the copy in contact with the carpet, directing the product towards the entrance of the channel intended for the product for reveal the latent image.

According to one embodiment, the collection means are constituted by a collector produced by means of a band secured to the periphery of an area provided with through openings of the carpet.

According to another embodiment, the collection means can be constituted by a collector formed by a profile of open section, closed at at least one end, secured to the periphery of an area provided with carpet openings.

According to yet another embodiment, the collection means consist of a collector formed by a hollow cylinder closed at at least one end, the wall of the cylinder being provided with at least one opening placed substantially along a generatrix of the cylinder close to the area with carpet openings.

According to a variant, the collector can be held in place by a strip secured to the carpet so that the opening is located as close as possible to the zone provided with carpet openings.

According to another variant, the collector is provided with two fins located on either side of the opening, said fins being secured to the carpet in such a way that the opening is located as close as possible to the zone provided with openings of the carpet. .

The various embodiments of the collection means can be analogous to those described for the channel intended for the product to reveal the latent image, thus the collection means can be constituted, like the channel, by a fold of the carpet, located on the face of the mat not in contact with the copy.

A diazocopy apparatus according to the present invention which includes means for recovering the unused product can, of course, include degassing means, downstream from the means for recovery, in relation to the direction of movement of the original and the copy.

Generally the calorific energy released by the light source of the diazocopy apparatus, object of the invention, is sufficient for the development of the latent image to be correct and the image obtained to be of good quality.

In order to improve the development efficiency, it may be advantageous for the product used to develop the latent image to be hot, so the diazocopy apparatus, according to the invention, can also comprise means for heating the product.

The product can be heated in a suitable device before being fed into the channel, it can also be heated by a heating means, such as an electrical resistance placed in the channel.

Optionally, the diazocopy apparatus may include means for preheating the product.

According to one embodiment, the preheating means consist of a circulation tube connected at one end to the inlet of the channel and at the other end to the source of product, said tube being located in the vicinity of the channel.

The vicinity of the channel is generally a hot region of the diazocopy machine because the product for revealing the latent image is fed into the channel after being heated and / or heating means are provided in order to directly heat the product in the channel.

In order to further improve the efficiency of the development of the latent image, it may be advantageous for the latter to be heated. Thus, the diazocopy apparatus, object of the invention, may also include means for preheating the copy located upstream of the channel.

According to one embodiment, the means for preheating the copy are constituted by an electrical resistance placed in the vicinity of the face of the mat not in contact with the copy, upstream of the channel.

According to another embodiment of the diazocopy apparatus, object of the invention, the means for heating the product and the means for preheating the copy are constituted by an electrical resistance associated with a reflector located in the vicinity of the channel and arranged of so that the reflector directs the heat radiation on the channel and an area of the face of the carpet not in contact with the copy, adjacent to the channel and situated upstream of the latter.

According to one embodiment, the diazocopy apparatus, according to the invention, can be such that the electrical resistance is placed in a housing provided in the reflector and that the means for preheating the product consist of conduits provided in the reflector .

Such a reflector can be formed by a profile, for example aluminum, the housing for the electrical resistance and the conduits being obtained directly during the manufacture of the profile.

In order also to improve the efficiency of the development of the latent image, it may be advantageous for the diazocopy apparatus to include means for humidifying the copy located upstream of the channel.

Humidification of the copy can be achieved by contacting it with a humid gas, such as moist air. Thus, the means of humidifying the copy can be constituted by a channel located on the face of the carpet not in contact with the copy, the interior space of the channel communicating with the face of the carpet in contact with the copy by means of openings passing through said mat, said channel being provided with means for entering and leaving wet gas.

The various embodiments of this channel are similar to those described for the channel intended for the product to reveal the latent image and for the collection means. They will not be described specifically.

In a diazocopy apparatus comprising a channel intended for the circulation of wet gas, the means for preheating the copy can be constituted by an electrical resistance placed in the channel for circulation of wet gas.

For the original and the copy to be correctly entrained by the cylindrical surface it is necessary that the carpet closely matches the surface, for this, the carpet is thin in order to present sufficient flexibility which allows it to follow as well as possible. irregularities of the cylindrical surface.

In order for the copy to slide on the surface of the carpet, the surface of the carpet in contact with the copy must be relatively smooth.

The carpet can be made using a sheet of various materials, such as a metal sheet or plastic, the chosen material must, of course, have good resistance to the product to reveal the latent image.

A carpet made of polytetrafluoroethylene is particularly suitable. Indeed, polytetrafluoroethylene makes it possible to obtain a relatively flexible carpet, resistant to corrosion and of a satisfactory surface condition, in addition, the low coefficient of friction of polytetrafluoroethylene promotes the sliding of the copy in contact with the carpet.

In order to further improve the sliding of the copy in contact with the mat, it may be advantageous to load the polytetrafluoroethylene with glass beads, this also has the advantage of reducing the deposition of polytetrafluoroethylene on the cylindrical surface by wear of the mat, the possible contact of the mat and the cylindrical surface then being made by means of the glass balls.

The carpet can also be made of a textile material, such as for example a polytetrafluoroethylene fabric or a glass fabric. A glass cloth carpet can advantageously be coated with a resin such as polytetrafluoroethylene.

According to the invention, the mat is provided at each of its ends with attachment zones formed by two profiles provided with fixing means at each end of the mat and means for attaching the profile to an attachment means provided for this purpose. in the structure of the diazocopy machine.

So that the carpet closely matches the cylindrical surface and best follows irregularities thereof, it is preferable that the diazocopie apparatus includes means for automatically adjusting the tension of the carpet.

These adjustment means make it possible to obtain a substantially constant contact pressure of the carpet on the cylindrical surface regardless of its cylindricity or whether an original and a copy are entrained or not between the carpet and the surface. Constant tension of the belt allows the original and the copy to be moved at high speed regular and avoids any overload of operation of the drive motor of the cylindrical surface.

Advantageously, according to one embodiment, the means for automatically adjusting the tension of the carpet can be constituted by at least one flexible blade acting on the face of the carpet not in contact with the copy, between the fastening profile and the first contact line of the mat and the cylindrical surface. Preferably the diazocopy apparatus includes two means for adjusting the tension of the belt.

According to another embodiment, the means for automatically adjusting the tension of the belt can be constituted by elastic means placed between the profile and the hooking means provided in the structure of the diazocopy apparatus. Preferably, the diazocopy apparatus includes means for automatically adjusting the tension of the belt constituted by elastic means in the vicinity of each profile.

According to yet another embodiment, the means for automatically adjusting the tension of the belt can be constituted by elastic means such as an elastic blade, for example made of rubber, interposed between the fastening profile and the end of the carpet. Preferably, an elastic blade is provided at each end of the mat.

The diazocopy original reproduction apparatus can be used alone, it can also include a copy paper feed module.

• La figure 1 est une vue en coupe par un plan perpendiculaire à la surface cylindrique d'un mode de réalisation d'un appareil de diazocopie objet de l'invention.
• La figure 2 est une vue en coupe par un plan perpendiculaire à l'axe du cylindre d'exposition d'un autre mode de réalisation d'un appareil de diazocopie, objet de l'invention.
• La figure 3 est une vue de détail en coupe par un plan exial d'un mode d'entrainement du cylindre d'exposition.
• La figure 4 illustre un mode de réalisation du tapis.
• La figure 5 est une coupe par un plan perpendiculaire à l'axe du cylindre d'exposition du tapis selon le mode de réalisation représenté figure 4.
• La figure 6 est une vue en coupe par un plan perpendiculaire à l'axe du cylindre d'xposition d'un autre mode de réalisation d'un appareil de diazocopie selon la présente invention.
• La figure 7 est une vue de détail des canaux et de distributeurs de l'appareil de diazocopie selon la figure 6.
• La figure 8 illustre un autre mode de réalisation du tapis.
• La figure 9 illustre un mode de réalisation du canal en coupe par un plan perpendiculaire à l'axe du cylindre d'exposition.
• La figure 10 représente un autre mode de réalisation du canal en coupe par un plan parallèle à l'axe du cylindre d'exposition.
• La figure 11 est une coupe par le plan XI XI d'un canal selon le mode de réalisation représenté figure 10.
• Les figures 12, 13 et 14 illustrent d'autres modes de réalisation du canal en coupe par un plan perpendiculaire à l'axe du cylindre d'exposition.
• La figure 15 est une vue en coupe par un plan perpendiculaire à l'axe du cylindre d'exposition d'un mode de réalisation des moyens de récupération.
• La figure 16 représente en coupe un mode de réalisation de la zone d'accrochage du tapis.
• La figure 17 est une section d'un mode de réalisation du réflecteur.
• Les figures 18a et 18b représentent un autre mode d'entrainement du cylindre d'exposition, en coupe par un plan perpendiculaire au cylindre d'exposition et en vue de dessus par rapport au tapis.
• La figure 19 est une vue schématique d'un appareil de reproduction d'originaux par diazocopie, objet de l'invention, comportant un module d'alimentation de papier, en coupe par un plan perpendiculaire à l'axe du cylindre d'exposition.

The invention will be better understood from the description of the attached figures, which illustrate schematically, by way of examples, and without a given scale of the embodiments of the invention.

• Figure 1 is a sectional view through a plane perpendicular to the cylindrical surface of an embodiment of a diazocopy apparatus object of the invention.
• Figure 2 is a sectional view through a plane perpendicular to the axis of the exposure cylinder of another embodiment of a diazocopy apparatus, object of the invention.
• Figure 3 is a detail view in section through an exial plane of a drive mode of the exposure cylinder.
• FIG. 4 illustrates an embodiment of the carpet.
• FIG. 5 is a section through a plane perpendicular to the axis of the exposure cylinder of the carpet according to the embodiment shown in FIG. 4.
• Figure 6 is a sectional view through a plane perpendicular to the axis of the exposure cylinder of another embodiment of a diazocopy apparatus according to the present invention.
• FIG. 7 is a detailed view of the channels and of the distributors of the diazocopy apparatus according to FIG. 6.
• Figure 8 illustrates another embodiment of the carpet.
• FIG. 9 illustrates an embodiment of the channel in section through a plane perpendicular to the axis of the exposure cylinder.
• FIG. 10 shows another embodiment of the channel in section through a plane parallel to the axis of the exposure cylinder.
• FIG. 11 is a section through the plane XI XI of a channel according to the embodiment shown in FIG. 10.
• Figures 12, 13 and 14 illustrate other embodiments of the channel in section through a plane perpendicular to the axis of the exposure cylinder.
• Figure 15 is a sectional view through a plane perpendicular to the axis of the exposure cylinder of an embodiment of the recovery means.
• FIG. 16 shows in section an embodiment of the belt attachment zone.
• Figure 17 is a section of an embodiment of the reflector.
• Figures 18a and 18b show another mode of driving the exposure cylinder, in section through a plane perpendicular to the exposure cylinder and in top view relative to the mat.
• Figure 19 is a schematic view of an apparatus for reproducing originals by diazocopy, object of the invention, comprising a paper feed module, in section through a plane perpendicular to the axis of the exposure cylinder.

The invention will be described below with more specific reference to the use of a gaseous product to reveal the image the tent. It is not, of course, outside the scope of the invention to use a liquid product to reveal the latent image.

The diazocopy apparatus (1), an embodiment of which is shown in FIG. 1 in section through a plane perpendicular to the axis of the cylindrical surface (2), comprises a body (not shown) fixed to a support frame, constituted two flanges (not shown) connected by two spacers (4, 5), for example of aluminum profile. Inside the bodywork, the diazocopy apparatus includes means for driving the copy and the original, exposure means for exposing the copy through the original and means for revealing the latent image. .

According to this embodiment, the exposure means (102) consist of a cylindrical surface (2) of closed director, formed by an endless strip (103), substantially transparent, enveloping two rollers (104, 105) , the light source consists of three exposure lamps (106) placed between the rollers (104, 105) between the parallel strands (109,110) of the endless strip (103). The strip (103) is driven in movement for example by means of the roller (104) itself driven in rotation.

The means for driving the original and the copy consist of the band (103) driven in movement which cooperates with a fixed mat (6) stretched between two attachment zones (7, 8).

The strip (103) can be made of any material provided that it has good light permeability and, advantageously, has sufficient adhesion to entrain the original and the copy, for this the surface of the strip may be provided with a coating.

The fixed mat (6) which cooperates with the strip (103) is, according to the present embodiment, formed by a sheet of plastic material, which here is polytetrafluoroethylene. The mat is stretched between two attachment zones (7, 8) [see detail] formed by two profiles (14) provided with fixing means (15), such as rivets, at each end of the mat (6). The profile (14) also comprises fixing means (16), formed by bending the profile (14) in L to hooking means provided for this purpose in the structure of the device. diazocopy. According to the embodiment shown, these attachment means are formed by a groove (18) located between two fins (17) carried by the spacers (4, 5), along their entire length.

The mat (6) envelops part of the cylindrical surface formed by the band (103), to allow engagement, movement and output of the original and a copy between the mat (6) and the band ( 103).

In order for the carpet (6) to best fit the cylindrical surface (103), the diazocopy apparatus includes means for automatically adjusting the tension of the carpet (6). These means consist of a flexible blade (19), for example made of rubber, carried by a rod (20) fixed at its ends to the flanges, the flexible blade (19) acting on the face (24) of the mat (6) not in contact with the copy between the attachment profile (14) and the first (21) and the last (28) contact lines of the mat (6) and the strip (103).

According to the embodiment shown in Figure 1, the diazocopy apparatus includes two flexible blade adjustment means (19).

After describing the means for driving the original and the copy, we will describe below the means for revealing the latent image carried by the copy, which are means for bringing the copy into contact with a product for reveal the latent image.

In the diazocopying apparatus, according to the invention, the means for bringing the copy into contact with the product to reveal the latent image are formed by a channel (22) located on the face (24) of the mat (6) not in contact with the copy, the interior space of the channel (22) communicates with the face of the copy in contact with the carpet (6) by means of openings (26) passing through the carpet (6). The channel (22) is, of course, provided with tubing (27) for inlet and outlet of the product to reveal the latent image carried by the copy.

The openings (26) passing through the belt (6) are grouped into a strip placed along a generatrix of the cylindrical surface formed by the strip (103). The strip formed by the openings (26) is such that its length is equal to the useful width of the diazocopy machine and its width is between 0.05 and 20% det preferably between 0.1 and 15% of the length of the wrapping arc of the cylindrical surface (103) by the belt (6), the wrapping arc being counted between the contact lines (21) and (28) between the belt (6) and the cylindrical surface (103), the lines (21) and (28) are generatrices of the cylindrical surface.

Thus, in the diazocopy apparatus, object of the invention, one point of the copy is brought into contact with the development product only during its travel time necessary to cover the width of the strip provided with openings ( 26).

The original and the copy, which are introduced in (107) into the diaocopy machine and come out in (108), travel in the machine a common path by being superimposed around the exposure means, this common path being limited by the generators (21) and (28) of the first and last contact of the belt (6) and the endless belt (103).

According to the embodiment represented in FIG. 1, the means for revealing the latent image are placed in such a way that the original and the superimposed copy have traversed approximately two thirds of their common path in the diazocopy machine before the copy is in contact with the product to reveal the latent image.

As shown in Figures 4 and 5, the channel (22) is formed by means of a preformed strip (29) secured, for example by gluing, at the periphery of the strip formed by the openings (26) of the carpet.

The strip may consist of a textile material, for example a glass fabric, coated with a resin, or may consist of a sheet, for example of polytetrafluoroethylene.

The diazocopying apparatus, according to the invention, also comprises means for degassing the copy constituted by an area (30) of the mat (6) provided with through openings placed downstream of the channel (22) relative to the direction of displacement of the copy and by suction means (31) located in the vicinity of the area (30) of the carpet (6) provided with openings and acting on the face (24) of the carpet (6) not in contact with the copy.

According to the present embodiment, the suction means (31) consist of a box (83) held in depression by connection with the suction side of a fan, the wall of the box has an open area (84) located in the vicinity of the area (30) provided with openings of the belt (6). The walls (85, 86) of the box limiting the open area (84) extending on either side of the area (30) provided with openings substantially up to the face (24) of the mat (6) not in contact with the copy.

As can be seen, the diazocopy apparatus, object of the invention, according to the embodiment shown in Figure 1 does not include special heating means. Indeed, the calorific energy released by the light source is sufficient for the development of the latent image to be effective and for the image obtained on the copy to be of good quality.

Guides (40) and (41), formed for example by folded sheets, make it possible to guide the original and the copy respectively, at the entry and the exit of the diazocopie apparatus.

The guide (40) preferably comprises a contact (42) which, when activated by the front edge of the original and of the superimposed copy, controls the supply of the product in the channel (22). When the contact (42) is deactivated, after passing the rear edge, it controls, with a delay, the stopping of the supply of the product in the channel (22). Thus, in the channel (22) the product practically circulates only for the time necessary to reveal the latent image.

The contact (42) can also control the switching on and off of the light source, ie lamps (106).

The operation of the diazocopy apparatus, according to the invention, will be described briefly below.

An original and a superimposed copy are introduced, guided by the guide (40) between the carpet (6) and the strip (103) according to the arrow F₄. When the front edge of the assembly passes over the contact (42), the lighting of the lamps (106) and the supply of the product in the channel (22) are controlled. Under the effect of the movement of the strip (103) which cooperates with the fixed belt (6), the original and the copy are entrained between the belt (6) and the strip (103).

During the passage of the original and the copy superimposed in contact with the strand (109) of the strip (103), the copy is exposed through the original and the latent image is thus formed on the copy. The whole, the copy of course being located in contact with the mat (6), then continues its common path in the device. When the copy carrying the latent image reaches the strip provided with openings (26) of the mat (6), the copy is then brought into contact with the product supplied in the channel (22) passing through the openings (26) of the carpet (6), and the latent image becomes visible.

The original and the copy continue their movement between the belt (6) and the strip (103) when passing in contact with the zone (30) provided with openings, the residual gases on the copy are sucked into the box (83) and directed to a neutralization station. When the rear edge of the original and the copy pass over the contact (42), the latter is released and it controls the extinction of the lamps and the stopping of the supply of product in the channel (22) , the extinction and the stop will intervene with a certain delay.

The original and the copy then exit from the diazocopy apparatus according to the arrow F₆, the original and the copy being separated manually by the operator, the copy is ready for use.

The diazocopy apparatus (1), according to the embodiment shown in section in Figure 2, comprises a body (3) fixed to a support frame, consisting of two flanges (not shown) connected by two spacers (4, 5) , for example in aluminum profile. Inside the bodywork (3) the diazocopy apparatus includes means for driving the copy and the original, exposure means and development means.

The exposure means (102) are, according to this embodiment, constituted by a cylindrical surface of circular director, which we will call hereinafter "cylinder" (2) provided internally with a light source formed by five lamps exhibition (106). The cylinder (2) is rotated.

The means for driving the original and the copy consist of the cylinder (2) driven in a rotational movement which cooperates with the fixed mat (6) stretched between two attachment zones (7,8).

The cylinder (2) is supported at its ends by the flanges (9) [Figure 3] provided with cylindrical surfaces (10). The cylinder (2) is provided at its ends with end caps (11). At one end of the cylinder (2) as shown in FIG. 3, the end piece (11) is integral with the cylinder (2), it is for example force-fitted or glued, and provided with drive means in rotation of the cylinder (2), these means possibly being a pinion (12). In order to facilitate the rotation of the cylinder (2) relative to the cylindrical surface (10) of the flange (9), a ring (13) can be placed between the end piece (11) and the cylindrical surface (10), for example in polytetrafluoroethylene. The ring (13) turns freely relative to the end piece (11) on the one hand, and relative to the cylindrical bearing surface (10) of the flange (9) on the other hand.

The cylinder (2) can be made of any material provided that it has good light permeability and mechanical properties such that the cylinder (2) is practically undeformable.

For the production of a diazocopy apparatus according to this embodiment, a cylinder (2) made of glass or polycarbonate is particularly suitable. Advantageously, the surface condition of the cylinder (2) is such that it has sufficient adhesion to cause the original and the copy, for this the surface of the cylinder can be provided with a coating, if the latter does not affect the light permeability of the cylinder. Preferably the surface condition of the cylinder (2) will have been modified, for example by a chemical or physical process. Thus, a glass cylinder whose outer surface has been lapped is very satisfactory, because on the one hand the light permeability of the cylinder has practically not been reduced and on the other hand the adhesion of the original on the cylinder has been increased.

The fixed belt (6) which cooperates with the cylinder (2) is, similar to that of the diazocopy apparatus shown in FIG. 1. The means by which the belt (6) is stretched between the attachment zones (7,8 ) are also similar to those described above.

The carpet (6) envelops part of the surface of the cylinder (2), to allow the engagement of the original and the copy between the carpet (6) and the cylinder (2).

So that the mat (6) best follows the irregularities of the cylinder (2), the diazocopy apparatus includes means automatic adjustment of the tension of the belt (6) with flexible blade (19) such as those previously described.

In the diazocopying apparatus, according to FIG. 2, the means for bringing the copy into contact with the product to reveal the latent image are also formed by a channel (22) located on the face (24) of the mat (6) not in contact with the copy, the interior space of the channel (22) communicating with the face of the copy in contact with the mat (6), that is to say with the face (25) of the mat (6) in contact with the copy, by means of openings (26) passing through the carpet (6).

According to the embodiment shown, the means for bringing the copy into contact with the product to reveal the latent image are placed substantially in the middle of the common path of the original and the copy in the diazocopy apparatus.

The openings (26) passing through the carpet (6) form a strip placed along a generatrix of the cylinder (2) such that its width is between 0.05 and 20% and preferably between 0.1 and 15% of the length of the cylinder wrapping arc (2) by the belt (6).

The diazocopying apparatus, according to the invention, also comprises means for degassing the copy constituted by an area (30) of the mat (6) provided with through openings placed downstream of the channel (22) relative to the direction of movement of the original and the copy and by suction means (31) located in the vicinity of the area (30) of the carpet (6) provided with openings and acting on the face (24) of the carpet (6) not in contact with the copy.

According to the embodiment shown, the suction means (31) are formed by a hollow cylinder (32) closed at one end and the other end of which is connected to the suction side of a fan. The wall of the cylinder (32) is provided with a through opening (33), placed substantially along a generatrix of the cylinder (32) close to the zone (30) provided with openings in the belt (6). During the operation of the diazocopy apparatus, the residual gases on the copy are sucked towards the inside of the cylinder (32) through the opening (33). The opening (33) can be a slot or a plurality of holes.

Such an embodiment of the suction means allows perform an efficient degassing of the copy.

Although the calorific energy released by the exposure lamps (106) is sufficient, the diazocopy apparatus may include means for heating the product and means for preheating the copy.

Thus, according to the embodiment shown in FIG. 2, the means for heating the product and the means for preheating the copy are formed by an electrical resistance (34) associated with a reflector (35) located in the vicinity of the channel (22) arranged in such a way that the reflector (35) directs the heat radiation onto the channel (22) and an area (36) of the face (24) of the mat (6) adjacent to the channel (22) and situated upstream of the latter . The resistor (34) and the reflector (35) are placed inside a screen (37) provided with wings (38) extending as far as the belt (6), this screen (37) has to prevent the heating of the other parts of the diazocopy machine.

The resistor (34), the reflector (35) and the screen (37) of course extend parallel to a generator of the cylinder (2) over the entire useful width of the diazocopy apparatus.

The resistor (24), the reflector (35) and the screen (37) are fixed to each other by suitable means and are then fixed to a closure panel (39) of the dia copy machine, the closure panel ( 39) being for example screwed to the spacers (4) and (5).

Thus, it suffices to remove the closure panel (39) to have access to the electrical resistance (34) on the one hand, to the channel (22) and to the pipes (27) on the other hand.

Guides (40) and (41), formed for example by folded sheets, make it possible to guide the original and the copy, respectively at the entry and the exit of the diazocopie apparatus.

The guide (40) preferably comprises a contact (42) which controls the supply and the stopping of the supply of the product in the channel (22), the lighting and extinction of the lamps (106).

Between the guides (40) and (41), towards the front of the device, a screen (111) is preferably placed, the face (112) of which faces the cylinder (2) is reflective. This screen (111) protects, on the one hand, the user of the light and, on the other hand, reflect it towards the cylinder (2).

The operation of the diazocopy apparatus, according to this embodiment will be described briefly below.

An original and a copy are introduced, guided by the guide (40) between the carpet (6) and the cylinder (2) according to arrow F₄, the original being in contact with the cylinder (2).

When the front edge of the assembly passes over the contact (42), the lighting of the lamps (106) and the supply of product in the channel (22) are controlled. Under the effect of the rotation of the cylinder (2) which cooperates with the fixed belt (6), the original and the copy are entrained between the belt (6) and the cylinder (2).

During the passage of the original and the copy superimposed between the cylinder (2) and the belt (6) upstream of the channel (22) relative to the direction of movement of the assembly, the copy is exposed through the original and the latent image is thus formed on the copy. The copy already subjected to the calorific action of the lamps (106) is preheated during its passage in contact with the area (36) of the mat (6). The copy carrying the latent image then reaches the strip formed by the openings (26) of the mat (6), the copy is then brought into contact with the product supplied in the channel (22) passing through the openings (26) of the carpet (6), and the latent image becomes visible.

The original and the copy continue their movement between the belt (6) and the cylinder (2), when passing in contact with the zone (30) provided with openings, the residual gases on the copy are sucked into the hollow cylinder (32 ) through the opening (33) and directed towards a neutralization station. When the rear edge of the original and the copy pass over the contact (42), the latter is released and it controls the extinction of the lamps and the stopping of the supply of the product in the channel (22) , the lights go out and the stop will occur with a certain delay so that the whole copy is passed in contact with the strip formed by the openings (26) of the carpet (6).

The original and the copy, then leave the diaocopy machine according to the arrow F₆, are separated by the operator, the copy is ready to be used.

Above the operation of the diazocopying apparatuses according to the invention represented in FIGS. 1 and 2 have been described with more specific reference to a copy whose support sheet coated with the diazo sensitive layer is porous, such as for example a sheet of paper, so that the product to reveal the latent image which is brought into contact with the back of the copy can pass through the support sheet and thus reach the sensitive diazo layer.

The photocopying machines, objects of the invention, can of course also be used with a copy whose support sheet is not porous, such as for example a polymer film. With such copies it suffices when the copy and the original are introduced into the apparatus to superimpose the original and the copy in such a way that the sensitive diazo layer of the copy is not in contact with the original but is located in contact with the carpet. The latent image is then formed on the sensitive diazo layer by exposure through the original and through the support sheet and the latent image is revealed directly when brought into contact with the product to reveal the latent image.

It is also possible, with the diazocopying apparatus according to the invention, to make a copy of which the support sheet is not porous in two stages. In a first step, the superimposed original and copy are introduced into the diazo copy machine so that the diazo sensitive layer is in contact with the original, the copy is thus exposed through the original and the whole leaves the diazocopy machine without the latent image becoming visible, the copy and the original are then separated manually by the operator. In a second step, the operator reintroduces the copy into the diazo copy machine so that the sensitive diazo layer is in contact with the carpet so that the product to reveal the latent image comes into contact with the latter.

A diazocopy apparatus according to the invention can then include a switch intended to stop the supply in the product channel to reveal the latent image during the first step.

The diazocopy apparatus (1), according to the embodiment shown in FIG. 6 in section through a plane perpendicular to the cylinder (2), comprises a body (3) fixed to a support frame, consisting of two flanges (not shown) connected by two spacers (4, 5), for example of aluminum profile. Inside the bodywork (3) the diazocopy apparatus comprises exposure means, means for driving the original and the copy and development means.

The exposure means are identical to those of the embodiment of the diazocopy apparatus shown in FIG. 2 and will not be described again.

The means for driving the original and the superimposed copy, as according to the embodiment shown in Figure 2, consist of a cylinder (2) driven in a rotational movement which cooperates with a fixed fixed belt (6) between two attachment zones (7, 8) formed by two curved sections (14) which cooperate with corresponding curved zones (80) provided on the spacers (4, 5).

So that the carpet (6) best follows the irregularities of the cylinder (2), the diazocopy apparatus includes means for automatically adjusting the tension of the carpet (6). These means are constituted by an elastic blade (81), for example made of rubber, interposed between the profile (14) and the end of the mat (6). Preferably an elastic blade (81) is provided at each end of the mat (6). The elastic blade (81) can be fixed on the one hand to the mat (6) and on the other hand to the profile (14) for example by means of rivets.

After describing the means for driving the original and the copy, we will describe below the means for revealing the latent image carried by the copy, which are means for bringing the copy into contact with a product for reveal the latent image.

In the diazocopying apparatus, according to the present embodiment, the means for bringing the copy into contact with the product to reveal the latent image are formed by two channels (22) located on the face (24) of the mat (6 ) not in contact with the copy, the interior space of the channels (22) communicates with the face of the copy in contact with the mat (6) by means of openings (26) passing through the mat (6). Each channel (22) is, of course, provided with product inlet and outlet pipes to reveal the latent image carried by the copy.

The openings (26) passing through the belt (6) form strips placed according to generatrices of the cylinder (2), to each channel (22) of course corresponds a strip of openings (26).

The bands formed by the openings (26) are such that their length is equal to the useful width of the diazocopy machine and the sum of their widths is between 0.1 and 20% and preferably between 0.2 and 15 % of the length of the wrapping arc of the cylinder (2) by the carpet (6), the wrapping arc being counted between the lines (21) and (28) of contact between the carpet (6) and the cylinder (2).

Thus, in the diazocopy apparatus, a point of the copy is in contact with the development product only during its travel time necessary to traverse the widths of the bands formed by the openings (26).

According to this embodiment of the diazocopy apparatus, object of the present invention, shown in Figure 6, a distributor (45) is placed in the channel (22). The distributor (45) occupies substantially the entire interior space of the channel (22), it has the shape of a hollow cylinder provided with an opening (49) in the form of a slot substantially along a generatrix (FIG. 7). The slot can of course be replaced by several openings, for example by a plurality of small holes, we have generalized in the present text by writing "opening (49)".

The distributor (45) is held in place by a strip (82) of textile material, for example glass fabric coated with a resin, which is secured to the mat (6) at the periphery of the strip formed by the openings ( 26), for example by gluing, to form the channel (22).

According to the embodiment shown in Figures 6 and 7, the same strip (82) of textile material forms the two channels (22) and holds the two distributors (45) in place so that their openings (49) are located at most near the corresponding bands formed by the openings (26) of the mat (6). Each distributor (45) is connected at its ends to inlet and outlet pipes for the product to reveal the latent image.

The diazocopy apparatus also includes degassing means (96) of the copy constituted by an area (30) of the mat (6) provided with through openings placed downstream of the channels (22) relative to the direction of movement of the original and the copy and by suction means (31) located in the vicinity of the zone (30) provided with openings of the carpet (6) and acting on the face (24) of the carpet ( 6) not in contact with the copy.

According to the present embodiment, the suction means consist of a box (83) maintained in depression by connection with the suction side of a fan, the wall of the box has an open area (84) located in the vicinity of the area. (30) provided with belt openings (6). The walls (85, 86) of the box limiting the open area (84) extend on either side of the area (30) provided with openings substantially up to the face (24) of the mat (6) not in contact with the copy.

The wall (113) of the box (83), opposite the open area (84), constitutes, according to the embodiment shown, a receiving area (115) of the copy located at the top of the diaocopy machine. . Advantageously, the wall (113) is provided with openings (114) communicating the reception area (115) of the copy with the interior of the box (83), thus a copy received on the reception area is subjected to the action of the degassing means (96). This embodiment is particularly advantageous for very long copies which can thus be subjected to the action of the degassing means as long as the rear edge of the copy has not come out of the diazocopy apparatus.

The diazocopy apparatus shown in Figure 6, comprises downstream means for bringing the copy into contact with the product to reveal the latent image, constituted by the channels (22), means for recovering (87) the unused product. The recovery means (87) are of course placed upstream of the degassing means (96) when the diazocopy apparatus includes such means.

The recovery means (87) of the unused product consist of an area (88) of the carpet (6) provided with through openings and collecting means (89) located in the vicinity of the area (88) connected to means suction acting on the face (24) of the carpet (6) not in contact with the copy, the suction means direct the recovered product to the inlet of the channels (22).

According to the embodiment shown in Figure 6, the collection means (89) are of a structure similar to that of the means for bringing the copy into contact with the product to reveal the latent image. The collection means (89) consist of a collector (90) in the form of a hollow cylinder closed at at least one end and provided with an orifice intended to bring the interior of the cylinder into depression. The wall of the manifold (90) is provided with at least one opening (91), such as a slot or a plurality of holes, placed substantially along a generatrix of the cylinder close to the area (88) provided with openings in the mat. (6). The collector (90) can be held in place, like the distributor (45), by means of a strip (92) secured to the face (24) of the mat (6) for example by gluing.

The diazocopy machine can of course include several recovery means (87).

A diazocopy apparatus as shown can have the distributors (45) and the collector (90) held by the same band, that is to say that the band (82) and the band (92) consist of a single piece of textile material.

The diazocopy apparatus, according to the present embodiment, includes means for preheating the product to reveal the latent image before the product is fed into the channel (22). According to the embodiment shown in Figure 6, the preheating means are constituted by a tube (93) for circulation of the product in a round trip connected at one end to the channels (22) and at the other end to the source of product, the tube (93) is located in the vicinity of the channels (22). This tube (93) is thus placed in the hottest zone of the diazocopy apparatus, that is to say in the zone on which the reflector (35) directs the heat radiation due to the electrical resistance (34) for heating the product flowing in the channel (22).

The operation of the diazocopy apparatus according to this embodiment will be briefly described below.

An original and a copy are introduced, guided by the guide (40) between the carpet (6) and the cylinder (2) according to arrow F₄, the original being in contact with the cylinder (2).

When the front edge of the assembly passes over the contact (42), the lighting of the lamps (106) and the supply of product in the channel (22) are controlled. Under the effect of the rotation of the cylinder (2) which cooperates with the fixed belt (6), the original and the copy are entrained between the belt (6) and the cylinder (2).

During the passage of the original and the copy superimposed between the cylinder (2) and the belt (6) upstream of the channel (22) relative to the direction of movement of the assembly, the copy is exposed through the original and the latent image is thus formed on the copy. The copy already subjected to the calorific action of the lamps (106), is preheated during its passage in contact with the zone (36) of the mat (6) on which the reflector (35) directs the calorific radiation due to the electrical resistance (34). The copy carrying the latent image then reaches the strip formed by the openings (26) of the belt (6), the copy is then brought into contact with the product supplied in the channels (22) and passing through the openings (26) of the carpet (6), the latent image becomes visible.

The original and the copy continue their movement between the carpet (6) and the cylinder (2), when passing in contact with the area (88) provided with openings, the product to reveal the latent image which has not summer used is sucked through the openings to the recovery means (87), then recycled to the inlet of the channels (22).

The original and the copy continue their movement between the belt (6) and the cylinder (2), when passing in contact with the zone (30) provided with openings, the residual gases on the copy are sucked into the box (83) and directed to a neutralization station. During the passage of the rear edge of the original and the copy on the contact (42) this is released, it controls the extinction of the lamps and the stopping of the supply of product in the channels (22), switching off the lamps and stopping will take place with a certain delay so that the entire copy is passed in contact with the strip formed by the openings (26) of the carpet (6).

The original and the copy, then leave the diaocopy machine according to the arrow F₆, are separated by the operator, the copy is ready to be used.

When the original and therefore the copy are of great length, the operator grasps the copy when it leaves the diazocopy machine and directs it to the reception zone (115) where it undergoes an additional degassing until the rear edges of the copy and the original come out of the diazocopy machine.

FIG. 8 shows another embodiment of the mat (6) in which the channel is formed by a profile (43) of open section secured by welding to the mat (6). The ends of the profile (43) are closed by plugs (44) traversed by the pipes (27) for inlet and outlet of the product.

Figure 9 shows yet another embodiment of the channel (22). This channel (22) is also formed by a section (43) of open section which has a shape such that the channel comprises a zone forming a gutter (76) situated at an altitude lower than the altitude of the strip formed by the openings of the carpet. It comprises at one end a tube for supplying liquid into the gutter (76) and at the other end a gas outlet tube in the upper part.

The liquid (77) circulating in the gutter (76) is heated by the heating means as shown in Figure 2, and generates vapors which pass through the openings (26) of the carpet (6) come into contact with the latent image and the latent image becomes visible.

Another embodiment of the channel (22) is shown in Figures 10 and 11. According to this embodiment, the channel (22) has, inside a dispenser (45) of product to reveal the latent image. The channel is formed by a profile (46), closed at its ends by two plugs (47, 48), secured, for example by gluing, to the periphery of the strip formed by the openings (26) of the belt (6). The distributor (45) consists of a hollow cylinder held in place by the plugs (47) and (48), the cylinder passing through the plug (47) is engaged in the plug (48), the plug (48) closing off this end. of the cylinder. The cylinder has a slot-shaped opening (49) substantially along a generatrix of the cylinder close to the strip formed by the openings (26) of the belt (6). The product for revealing the latent image is fed to the distributor (45) through the end of the latter situated on the side of the plug (47), leaves the distributor through the slot (49), according to a distribution in the form of a strip and passes through the carpet (6) through the openings (26) to come into contact with the latent image carried by the copy. The slot (49) can of course be replaced by a plurality of holes.

The channels for distribution in a strip are particularly suitable when the product for revealing the latent image is gaseous.

The means for bringing the copy into contact with the product to reveal the latent image represented in FIG. 12 are such that the channel (22) is constituted by a distributor (45) having the shape of a cylinder provided with at least one opening. (49), such as a slot, or a plurality of openings substantially along a generator. The distributor (45) is provided with two fins (95) located on either side of the opening (49) intended to secure, for example by gluing, the distributor (45) to the mat (6), at the periphery of the strip formed by the openings (26) of the belt (6).

Of course, two channels (22) as shown in Figure 12 may have a fin (95) placed between the distributors (45) common.

Channels according to the embodiment shown in Figure 12, can easily be obtained by extrusion in the form of a profile.

According to FIG. 13, the channel (22) is constituted, as described above, by a distributor (45) provided with two fins (95) secured to the mat (6), which has been cut into two parts (6A) and (6B), so that an opening (26) is made between the parts (6A) and (6B) of the carpet. This opening (26) forms a strip, it allows the communication of the interior space of the channel (22) with the face of the copy in contact with the mat (6). Such a channel can easily be obtained by extrusion.

According to this embodiment, the strip formed by the opening (26) can have a very small width. Preferably its width is between 0.05% and 20% and advantageously between 0.1% and 15% of the length of the wrapping arc of the cylindrical surface (2) by the belt (6).

For a photocopy machine comprising several channels (22) as described above, the sum of the widths of the bands formed by the openings (26) corresponding to the channels (22) will be between 0.1% and 20% and preferably between 0.2% and 15% of the length of the enveloping arc of the cylindrical surface (2) by the mat (6).

According to the embodiment of the means for bringing the copy into contact with the product to reveal the latent image shown in FIG. 14, the channel (22) is formed by a fold (119) of the mat (6), the fold being located on the face (24) of the mat (6) not in contact with the copy.

Inside the fold (119), that is to say on the face (25) of the mat (6) in contact with the copy, is inserted a hollow cylinder (45) provided with at least one opening (49) , such as a slot, placed substantially along a generator, such that the opening (49) is as close as possible to the cylindrical surface of the exposure means (2). The hollow cylinder forms a distributor ensuring a distribution in blade of the product to reveal the latent image on the face of the copy in contact with the carpet (6). The mat (6) is held on the hollow cylinder (45) by means of a split tube (12) of elastic material ensuring a pinching effect over the entire width of the mat.

According to this embodiment, the width of the opening (26), located at the base of the fold, can be very small.

The embodiments of the channels (22) described above and represented in figures 2,4,5,7,8,10,11,12,13 and 14 can of course be used to make the collector of the means for collecting the product. not used to reveal the latent image.

Another alternative embodiment of the collecting means (89) is shown in FIG. 15. The collecting means (89) here consist of a collector formed by a section (99) of open section, closed at one end, the other end being connected to suction means. The profile can be closed at both ends, it is then provided with a tube passing through its wall. The profile (99) is secured to the periphery of the area (88) provided with openings of the carpet (6) on the face (24) thereof not in contact with the copy.

FIG. 16 shows in section another embodiment of the attachment zone (7) of the belt (6) and of means for automatic adjustment of the tension of the belt (6).

The attachment zone is formed by a profile (14) having three wings (50, 51, 52), the wings (50) and (51) being substantially parallel. The mat (6) is engaged between the parallel wings (50, 51) and the assembly is deformed in a zigzag fashion by crushing between profiled rollers. The wing (52) of the profile (14) has holes (54) intended for hooking one end of a spring (55), the other end of the spring (55) being hooked to the wing ( 17) of the spacer (4) which is provided with holes (56). Thus, according to the present embodiment, a plurality of springs (55) distributed along the profile (14) constitutes elastic means for automatic adjustment of the tension of the belt (6).

The reflector (35) according to the embodiment shown in Figure 17 is formed of a metal profile, for example aluminum, in which are provided directly during manufacture, a housing (100) in which will be placed the heating resistor ( 34) and the two conduits (93) intended for the circulation of the product to reveal the latent image before its introduction into the channel (22), circulation thus allowing the preheating of the product. The reflector (35) according to this embodiment with two wings (101) extending as far as the vicinity of the mat (6) in order to avoid the heating of the other parts of the diazocopy apparatus.

Figures 18a and 18b show another mode of driving the exposure cylinder in section through a plane perpendicular to the axis of the exposure cylinder (2) [Figure 18a] and in top view relative to the mat (6 ) [Figure 18b].

According to this embodiment, the cylinder (2) is rotated strongly by means of a plurality of rollers (116) integral with a shaft (117), with an axis parallel to the axis of the cylinder (2) , the shaft (117) being rotated. The rollers (116) are in contact with the outer surface of the cylinder (2) through openings (118) made in the belt (6). The original and the superimposed copy are introduced into the diazocopy apparatus according to the arrow F between the rollers (116) and the cylinder (2).

The diazocopy apparatus according to the invention can include such drive means not only in the vicinity of the entry of the original and the copy in the diazocopy apparatus, but also in the neighborhood of the exit of the set.

An original reproduction apparatus according to the invention is shown in Figure 19 associated with a copy paper supply module (57).

The copy paper feed module (57) has substantially the shape of a rectangular housing (60) provided with an opening closed by a pivoting cover (61) to place one or more rolls (62) of paper copy in the housing (60). The rollers (62) can rotate freely on themselves under the effect of the traction of the copy paper (63), and are, for example, placed on a cradle (64) formed by two cylindrical rods parallel to the axis of the roller (62) and provided with means for immobilizing the roller (62) in translation.

The upper surface of the housing (61) has a copy paper exit slot (65) and a wire cutter (66).

The diazocopy apparatus (1) used is similar to that shown in FIG. 2, but it has neither a reflector (35) nor a heating resistor (34).

The use of such a copy-copying apparatus will be described briefly below.

The operator pulls the end of the copy paper (63) and places the original to be reproduced above it. It engages the assembly constituted by the original and the copy paper superimposed according to the arrow F₁ between the cylinder (2) and the mat (6). When moving this assembly around the cylinder (2) the latent image is formed on the copy by isolation through the original upstream of the channel (22). During the displacement of the original and the copy around the cylinder (2), the ammoniacal vapors brought by the channel (22) and brought into contact through the openings (26) of the mat (6) with the copy, reveal the latent image that becomes visible. The copy after passing along the area (30) of the mat (6) undergoes degassing and the copy and the original exit from the diazocopy apparatus according to the arrow F₅, the copy is ready to be used.

The apparatus for reproducing originals by diazocopy, object of the invention, has many advantages.

By design, the heat energy released by the light source is generally sufficient for the development of the latent image to be correct and the image obtained to be of good quality, it is therefore not necessary to '' equip the device with specific heating means. This has the advantage of simplifying construction and assembly, makes maintenance easy and reduces the cost of the device.

As can only be seen on reading the description above, the sealing problems are reduced to a minimum by the design of the diazocopy apparatus. Indeed, only the channel is traversed by the product and obtaining its tightness at the periphery of the strip provided with openings is easy to perform since the channel can be obtained either directly with the carpet or by bonding or welding of a strip or a profile at the periphery of the strip provided with openings.

In addition, the diazocopying apparatus according to the invention has the advantage of using only small volumes of product. Indeed, on the one hand, the volume of the channel is low and, on the other hand, the product is fed into the channel only for the time necessary for the passage of the original and the copy in the machine of diazocopy.

In addition, the diazocopy apparatus, object of the invention, is particularly effective during the development of a latent image by ammoniacal vapors. In fact, development is all the more effective as the speed of the gas coming into contact with the diazo layer is high, in the present diazocopy apparatus, on the one hand, the gas passage section, from the channel to the copy, is low since it is equal to the surface of the openings situated in the strip, and on the other hand, the volume of the channel being small the gas practically does not undergo expansion, it follows that the speed of the gas passing through the openings is high.

A diazocopying apparatus according to the invention which uses a product to reveal the gaseous latent image also has the advantage of being compact.

Indeed, the use of a small volume of gas makes it possible to considerably reduce, on the one hand, the size of the apparatus and on the other hand, its handling.

In addition, as the volume of gas used is low, on the one hand, the volume of gas recovered during degassing of the paper is also small, which makes it possible to reduce the size of the neutralization device and the neutralization device does not saturates only slowly, and on the other hand, the frequency of supply of the ammonia vapor generation station is low.

Claims (24)

1. - Apparatus for reproducing originals by diazocopying, comprising in particular means for driving the original and the copy, exposure means for exposing the copy through the original to form a latent image on the copy and means for revealing the latent image carried by said copy, characterized in that the exposure means (102) comprise a light source (106) inside a cylindrical surface (2) of closed director, substantially transparent, driven in movement, the means for driving the original and the copy consist of a fixed mat (6) which cooperates with the cylindrical surface (2), the mat (6) being stretched between two zones of hanging (7, 8), said mat enveloping part of the cylindrical surface (2), the original and the copy moving under the effect of movement between the cylindrical surface (2) and the mat (6) and means for revealing the latent image carried by the copy are means for bringing the copy e in contact with the product to reveal the latent image, said means are formed by at least one channel (22), the interior space of the channel (22) communicating with the face of the copy in contact with the mat (6) by means of at least one opening (26), said channel (22) being provided with means (27) for inlet and outlet of said product. 2. - Apparatus according to claim 1, characterized in that said channel (22) is located on the face (24) of the mat (6) not in contact with the copy, the interior space of the channel (22) communicating with the face of the copy in contact with the mat (6) by means of openings (26) passing through said mat (6). 3. - Apparatus according to any one of claims 1 or 2, characterized in that it comprises a channel (22) and that the opening (s) (26) communicating the interior space of the channel with the face of the copy in contact with the mat (6) form a strip placed along a generatrix of the cylindrical surface (2), the strip being such that its length is substantially equal to the useful width of the device (1) and its width between 0 , 05 and 20% of the length of the arc of envelopment of the cylindrical surface (2) by the belt (6). 4. - Apparatus according to claim 3 characterized in that the width of the strip is between 0.1 and 15% of the length of the arc of wrapping of the cylindrical surface (2) by the belt (6). 5. - Apparatus according to any one of claims 1 out 2 characterized in that it comprises several channels (22) and that the opening (s) (26) communicating the interior space of a channel (22) with the face of the copy in contact with the mat (6) form strips, for each corresponding channel a strip placed substantially along a generatrix of the cylindrical surface (2), the strips being such that their length is substantially equal to the useful width of the device (1) and the sum of their widths between 0.1 and 20% of the length of the arc of envelopment of the cylindrical surface (2) by the belt (6). 6. - Apparatus according to claim 5 characterized in that the sum of the widths of the bands is between 0.2 and 15% of the length of the arc of envelopment of the cylindrical surface (2) by the belt (6) . 7. - Apparatus according to any one of the preceding claims, characterized in that the means for revealing the latent image are placed so that the original and the copy have traveled at least 50% of their common path in the apparatus. 8. - Apparatus according to any one of claims 1 to 7 characterized in that the channel (22) is produced by means of a strip secured to the periphery of the strip formed by the opening (s) (26). 9. - Apparatus according to any one of claims 1 to 7 characterized in that the channel (22) is formed by a profile (43) of open section secured to the periphery of the strip formed by the opening (s) (26) , and provided at its ends with plugs (44). 10. - Apparatus according to any one of the preceding claims, characterized in that a distributor (45) for the development product is placed in the channel (22). 11. - Apparatus according to any one of claims 8 to 10, characterized in that the distributor (45) occupies substantially the entire interior space of the channel (22). said distributor (45) having the shape of a hollow cylinder provided with at least one opening (49) substantially according to a generator and being held in place by the strip (29) forming the channel (22) so that the opening (49) is located as close as possible to the strip formed by the opening (s) (26), said distributor (45) being directly connected at its ends to product inlet and outlet tubes to reveal the latent image. 12. - Apparatus according to any one of claims 1 to 11, characterized in that the channel (22) is constituted by a distributor (45) having the shape of a hollow cylinder provided with at least one opening (49) substantially along a generator, said distributor (45) being provided with two fins (95) located on either side of the opening (49) to secure it to the mat (6) at the periphery of the strip formed by the or the openings. 13. - Apparatus according to any one of claims 1 to 9 characterized in that the channel (22) comprises a zone forming gutter (76) located at an altitude lower than the altitude of the strip provided with openings (26) of the carpet (6). 14. - Apparatus according to any one of the preceding claims, characterized in that it comprises means (42) which, in response to the passage of a copy, control the feeding or stopping of the feeding of the product in the canal. 15. - Apparatus according to any one of the preceding claims, characterized in that it comprises degassing means (96) of the copy downstream of the means for revealing the latent image relative to the direction of movement of the copy. 16. - Apparatus according to any one of the preceding claims, characterized in that it comprises downstream means (22) for bringing the copy into contact with the product to reveal the latent image of the recovery means (87) of the unused product. 17. - Apparatus according to claim 16 characterized in that said means (87) are constituted by collection means (89) connected to suction means acting on the face of the copy in contact with the carpet (6) said suction means directing the product towards the inlet of the channel (22). 18. - Apparatus according to claim 19, characterized in that the collection means (89) consist of a collector (90) formed a hollow cylinder closed at at least one end and provided with an orifice intended to bring the interior of the cylinder into depression, the wall of the cylinder being provided with at least one opening (91) placed in the vicinity of the face of the copy in contact with the mat (6). 19. - Apparatus according to any one of the preceding claims, characterized in that it comprises means for heating the product and / or means for preheating and / or humidifying the copy located upstream of the channel (22) . 20. - Apparatus according to claim 19, characterized in that the means for heating the product and / or the means for preheating the copy consist of an electrical resistance (34) associated with a reflector (35) located in the vicinity of the channel (22) and arranged in such a way that the reflector (35) directs the heat radiation onto the channel (22) and an area (36) of the face (24) of the mat (6) not in contact with the copy, adjacent to the channel (22) and located upstream thereof. 21. - Apparatus according to any one of the preceding claims, characterized in that the attachment zones (7, 8) of the carpet (6) are formed by two profiles (14) provided with fixing means (15) to each end of the mat (6) and of means (16) for fixing the profile (14) to a hooking means (17, 18) provided in the structure (4) of the device (1). 22. - Apparatus according to any one of the preceding claims, characterized in that it comprises means for automatic adjustment of the tension of the belt (6). 23. - Apparatus according to any one of the preceding claims characterized in that the cylindrical surface has a circular director. 24. - Apparatus according to claim 38 characterized in that the cylindrical surface of circular director is the outer surface of an exposure lamp.

Images