FR2605759A1 - Apparatus for arranging several developing devices, apparatus for forming images and developing device - Google Patents

Abstract

The invention relates to an apparatus for forming images, fitted with a magazine with several developing devices. The developing devices 13A, 13B, 13C, 13D are housed inside an arrangement container 150 which can be moved vertically in front of an opening, the latter being closable by a shutter 55, in the main body 100 of an image formation apparatus. Field of application: colour image formation apparatuses.

Description

 An apparatus for storing or housing multiple development devices for an image forming apparatus such as a copying machine, a recording machine and a printer, and also relates to a training apparatus for images and a developing device which can be used with such an apparatus, and more particularly to apparatuses of this type in which the developing device can be removably mounted in the image forming apparatus.

 Typically, a developing device is set up in an image forming apparatus such as a copying machine by an experienced service agent, after which the user operator does not remove the developing device from the copy machine. Consequently, in most cases, a maintenance agent manually introduces the developing device into the machine to a position, for example, in which the developing device is near a photosensitive element, but without touching it, then a manual lever is operated to apply the development device against the photosensitive drum in order to position it correctly with respect to the latter. This type is described in United States patents Nos. 4,373,468 and Nos. 4,583,832, for example.

 However, a new type of imaging device has recently become widespread, in which the developing device can be replaced by another developing device containing a pigment powder, or ink powder or "toner" of a different color, such as red and blue powders, in addition to the black powder, to allow the formation of images with a different color. As a result of this trend, it is more common for the user operator to mount the development device in or out of the device himself. This type is described, for example, in United States patents of America Nos. 4,470,689, Nos. 4,500,195 and Nos. 4,575,221, in which a processing unit containing a photosensitive element and developing means is replaced, and in the United States patent application America N 802 537, deposited on November 27, 1985, in which the apparatus contains two development devices which can be used selectively, one of these development devices being made interchangeable.

 United States Patent Application No. 844,718, filed March 27, 1986, describes another proposal in which two development devices can be selectively activated.

The United States patents N 4 615 612 and N 4 622 916 describe another proposal in which the apparatus comprises means housing a developer, of the turret type.

 However, since all of the systems described above involve manual exchange or replacement of the development device, this requires difficult work and implies the possibility for the development device to strike the device or the like, thereby communicating a shock or unnecessary vibration to the developing device.

 Furthermore, if we consider the development operation, the size of the developer particles becoming smaller and smaller to improve the image quality, in particular the sharpness, this results in an increase in the fluidity of the developer. when the latter is mixed with air. It therefore becomes necessary to handle the development device with great care because, otherwise, the developer risks being distributed unevenly in the container or dispersing outside.

 In general, uneven distribution of the developer in the container is eliminated by agitation of the developer and, taking into account the variations between the ways in which the various users carry out the manipulations, the agitation period is relatively extended to cover wide variations.

Therefore, the time required until a first copy can be obtained is long after exchanging the developing device or after the developer has been introduced into the type of device in which said developing device is removed from the device. device so that the developer can be charged. When the movement of the developing device is stopped by a stopper when this device is mounted in the apparatus, the degree of the resulting lack of uniformity in the distribution of the developer and the dispersion varies according to the speed at which the user places the development device against the stopper.

 More particularly, in the system in which the mounting of the development device is carried out by the user, the mounting operation is carried out in a similar manner to the closing of a drawer by the user and, consequently, the shock communicated to the development device differs according to the particular force with which the user mounts this device. If the force is great, the shock applied in the longitudinal direction to the developing device is violent (in the system in which the developing device is introduced through a front door of the device in the direction of a generator of a drum photosensitive that the device contains), and the developer located in the container is not distributed uniformly in the longitudinal direction. The developer having been rejected towards the back can then be expelled towards the outside while passing in the play of the circumference d 'a cover of the development device and disperse. In particular, when the developer device is recharged, a bottle containing a development reserve used for recharging is shaken so that the fluidity of the developer increases so that this developer can pass entirely from the bottom of the bottle into the container of the development device. This facilitates the dispersion of the developer.

 When the developing device is exchanged, the developer that its container contains has usually remained stationary for a relatively long period of time and, therefore, the fluidity is not as high. However, once the uniformity of its distribution has been broken, the developer must be agitated firmly and relatively strongly by means of agitation such as an agitation rod. Therefore, the prior rotation period of the photosensitive member to prepare the apparatus for an image forming operation should be lengthened. This also results in the lengthening of the period of time from switching on the device to be copied until the execution of the first copy.

 From the point of view of the users, various positioning means or other means must be operated during the disassembly or the assembly of the development device, and this operation is therefore troublesome.

 United States patent application No. 071,316, filed July 9, 1987, has proposed a solution to the above problems. This proposal contains, as a feature, a passage through the apparatus for formation of images to allow the development device to be mounted in the device or to be removed therefrom. The invention provides an additional improvement to this proposal by the fact that several development devices are introduced and put in place without require annoying handling on the part of users.

 Therefore, the main object of the invention is to provide an apparatus capable of storing several development devices, of small size and by means of which a development device containing a developer of the desired color can be chosen easily and reliably.

 The invention also relates to an image forming apparatus which can be used with an apparatus intended to store several development devices.

 Another subject of the invention is a development device which is suitable for use with an apparatus for storing several development devices.

 A small device has been developed which can store several development devices and therefore makes it possible to reduce the size of the entire image forming device.

The invention will be described in more detail with reference to the accompanying drawings by way of non-limiting examples and in which:
- Figure 1 is a longitudinal sectional view of an image forming apparatus according to an embodiment of the invention
- Figure 2 is a partial top plan view of the image forming apparatus, showing developer erasing means
- Figure 3 is a side view of the developer displacement means
- Figure 4 is a section along the line IV-IV of Figure 3
- Figure 5 is a perspective view of the image forming apparatus seen from the side of the device receiving the developer
- Figure 6 is a partial perspective view on an enlarged scale of Figure 5
- Figure 7 is a flowchart illustrating part of the operations performed in the part shown in Figure 1
- Figure 8 is a cross section showing the junction between the image forming apparatus and the apparatus housing the development devices
- Figure 9 is a partial top plan view illustrating an example other than that of Figure 8
- Figure 10 is a partial cross-section illustrating another important part - of the arrangement of Figure 9
- Figure 11 is a section illustrating the movement of a first example of the development device
- Figure 12 is a side view of the arrangement shown in Figure 11
- Figure 13 is a section illustrating a second, more advantageous example of the mechanism moving the developing device ----- nt
- Figure 14 is a section showing again this second example
- Figures 15 to 17 are top views, front and again from above showing a connecting element between the image forming apparatus and the apparatus housing the development devices;
- Figures 18 to 23 illustrate, in sectional views, in elevation and in perspective, the relationship between the apparatus housing the development devices and a mechanism for manually advancing a copy sheet
- Figures 24 and 25 are sections illustrating developer collection means associated with development passages
- Figure 26 is a perspective view of a variant of the apparatus shown in Figure 21 ;;
- Figures 27 to 31 illustrate in section, in elevation and in perspective, a safety mechanism for the device housing several development devices
- Figure 32 is a view showing a modification to the structures shown in Figures 13 and 14
- Figure 33 is a front sectional view of a structure according to Figures 32 and 13
- Figure 34 is a front sectional view showing a second example of the displacement means of the developing device in accordance with the structure of Figure 32
- Figure 35 is a front sectional view of part of another embodiment of an image forming apparatus according to the invention;
- Figure 36 is a side view of the embodiment of Figure 35
- Figures 37 and 38 are a front view and a side view of a third example of the displacement means.

 FIG. 1 represents an image forming apparatus, more particularly a copying machine in this example, used with an apparatus intended to receive several development devices in accordance with an embodiment of the invention.

The image forming apparatus of this example is capable of producing images on opposite sides of a sheet, in different colors, and is capable of forming superimposed images in different colors.

 Before describing this embodiment of the apparatus for receiving development devices, the image forming apparatus which can be used with the apparatus for storing development devices will be described.

 In the image-forming apparatus, an original 2 placed on an original carrier glass tray 1, is illuminated by a lamp 3, and the resulting light image is applied to a photosensitive drum (image-carrying element) 11 at by means of an optical system comprising reflecting mirrors 4, 5, 6, 7, 8 and 9 and a variable focal lens.

The lamp 3 and the mirror 4 as well as the mirrors 5 and 6 are moved at respective predetermined speeds in the direction indicated by an arrow A so as to scan the original '2. Furthermore, the photosensitive drum 11 is put in rotation in the direction indicated by an arrow B at the same time as it is uniformly charged by a main charger 12. The light image is applied to the surface of the photosensitive drum 11 which has therefore been electrically charged and a latent image is formed electrostatic according to the original 2. there is provided, in the immediate vicinity of the surface of the photosensitive drum 11, a device 13C for developing in a chromatic color containing a developer of a chromatic color (for example green) and a device 14 for development in black containing a black developer. The developing devices 13C and 14 can be moved in directions C and C ', respectively, to access the photosensitive drum 11 as a function of the choice of color for developing the electrostatic latent image, carried by the photosensitive drum 11, in one visible image. Figure 1 shows the chromatic development device (glass development device, for example) 13C distant from its working position, while the development device 14 in black is in its working position close to the photosensitive drum 11, so that a black image can be formed on the photosensitive drum 11.

The developed image is transferred onto a sheet of paper (recording medium) by a transfer charger 15. Next, the surface of the photosensitive drum 11 is moved to the cleaning means which includes a cleaning station 16 in which the remaining pigment powder or "toner" is removed from the surface of the photosensitive drum 11 so that it is ready for use. next image forming operation. The sheet 17 is advanced in the following manner. There are several types of feeding means intended to advance the sheet 17 to an image forming station comprising a photosensitive drum 11. In a first type, the sheet 17 housed in a cassette or an upper magazine 18 is advanced towards a pair 20 of rollers by a feed roller 19. The pair of rollers 20 has the effect, when two or more sheets 17 are advanced, of separating the highest sheet 17 and advance it to the imaging station. The sheet 17 having passed between the pair 20 of rollers advances towards a pair of framing rollers 23 being guided by plates and being advanced by a pair 50 of rollers and guided by other plates. In the second type, the sheet 17 housed in the lower cassette 18 is advanced towards a pair 26 of rollers by a feed roller 19, in a manner similar to that described above. The framing rollers 23 first stop the sheet 17 which arrives and start to rotate in synchronism with the developed image formed on the photosensitive drum 11 so that this image is aligned on the sheet. After the framing rollers 23 have started to turn, the sheet 17 is advanced towards the surface of the photosensitive drum 11 by means of an upper guide 31 and a lower guide 32.

The sheet 17 receives the image of the photosensitive drum 11 under the action of a transfer charger 15. The sheet 17 is then separated from the surface of the photosensitive drum 11 by the separation charger 34 and it is further advanced, by means of a transport passage 34, to an image fixing device 35 which contains a heating roller and a pressure roller. In the fixing device 35, the sheet 17 is heated and pressed so that the image which it carries is fixed to constitute a permanent image. Then, the sheet 17 is transported to a first discharge roller 36 and is further transported to a second discharge roller 39 by one of two valves 37 and 38 by means of which it is discharged from the device. the valve 38 is shown as closing the passage of the sheet but, since the valve 38 is made of a light and flexible material, it is therefore flexible in the direction indicated by an arrow B and it is lifted by the front edge of sheet 17 when it passes so as not to hinder the passage of sheet 17. We will now describe the circuit of sheet 17 in the duplex imaging mode and in the imaging mode in overlay.

 When the duplex imaging mode is selected in the image forming apparatus (images must be formed on the opposite sides of sheet 17), sheet 17 is transported in the same manner as that described above (mode for forming images on one side) so that the image of an original is transferred and fixed on one side (the first side) of the sheet.

The sheet is transported to the second discharge roller 39 and it is then advanced by the latter to a tray not shown. During this transport, the rear edge of the sheet 17 is detected by a sheet detection mechanism comprising a detection lever 40 and a photosensor 41 and, after a predetermined time (i.e. the period of time ending at the passage of the rear edge of the sheet 17 under the flap 38), the second discharge roller 39 begins to rotate in the opposite direction to reintroduce the sheet into the apparatus. The sheet 17 is brought back, its rear edge then being forward, along the flap 38 of an inclined surface on the left side of the flap 37 and the guide plate 42. In addition, it is transported by means of the plates 43 and 44 and is advanced towards rollers 45, its orientation being reversed. The sheet 17 is further advanced towards rollers of lateral alignment by means of rollers 46. At this moment, the lateral alignment rollers are at rest, so that the front edge of sheet 17 abuts in the clamping zone of the rollers 47 and then the pairs of rollers 45 and 46 stop. When an image signal on the second side is produced, the lateral framing rollers 47 begin to rotate in order to advance the sheet 17 along the guide plates. Before the sheet 17 reaches the framing rollers 23 , a lateral edge of the transfer sheet 17 is detected by a photosensor and the rollers 47 for lateral alignment correct the lateral position of the sheet 17 in the direction perpendicular to the direction of movement of this sheet 17, that is to say perpendicularly on the drawing board, to align the side edge with the position of the side edge of the first image formed. After the sheet 17 has reached the framing rollers 23, the operations are similar to those performed for the formation of an image on a single face, as described previously. After an image has been formed on the second face of the sheet 17, the latter is discharged towards the external tray by the second discharge rollers 39.

 When a superimposed image forming mode is selected in this image forming apparatus, the operation of forming the first image is the same as that performed for forming the image in the single mode face described previously. After the formation of an image on the first face, the flap 37 is placed in a position in which it is shown in broken lines, and therefore the sheet 17 is discharged by the first discharge rollers 36 and is transported towards the guides 42 and 43 following the inclined surface on the right side of the flap 37. It is further transported to the rollers 45 along the guides 43 and 44. Then the sheet 17 reaches the rollers 47 for lateral alignment by means of rollers 46. When a predetermined period of time ends after the detection of the rear edge of the sheet 17 by the detection lever 40 and the photosensor 41, the flap 37 is returned to the position in solid lines. When the signal for forming the second image is produced, the side alignment rollers 47 begin to rotate. The lateral translation of the sheet 17 is the same as that carried out in the case of the formation of an image on the second face in the operation of forming duplex images. After the second image has been formed on the transfer sheet 17, the latter is unloaded towards the external plate of the machine by the second unloading rollers 39. The preceding explanation relates to the case in which two images are superimposed, but more images can be superimposed, the leaf movements being basically the same. However, here, the repositioning of the flap 37 from the position in broken lines to the position in solid lines takes place only before the formation of the last image.

 The apparatus 150 intended to store or house several development devices according to one embodiment of the invention will now be described.

The developing device receiving apparatus 150 is optionally connected to an exterior face of the imaging apparatus 100, in this embodiment.

 The apparatus or magazine 150 can optionally be attached to an exterior face of the image forming apparatus 100 when it is desired to form chromatic color images using a chromatic color developing device other than the developing device in black which is fixed in the apparatus 100 of this embodiment. A desired color developing device is then transported and brought to the vicinity of the photosensitive drum 11 therein in the image forming apparatus 100.

The store 150 comprises, as main body, a housing enclosure 151 provided with bottoms or shelves 151a, 151b, 151c and 151d of partitioning which are produced in a single piece with the enclosure 151. Color developing devices chromatic, containing "toners" of different colors, for example a red development device 13A containing a red developer, a blue development device 13B containing a blue-development, a green development device 13C containing a green developer and a 73D developing device in brown containing a brown developer, are placed on the partitioning shelves 151a, 151b, 151c, 151d and can be moved from the shelves to the imaging device 100. In the state shown as a example in FIG. 1, the device 13C for developing in green is not in the enclosure 151, but in the device 100, in the immediate vicinity of the photosensitive drum 11 which is ready to develop the latent image. The transport or transfer of the development device in chromatic colors (development device in green 13C) is carried out by means
Transport X (means turning in the direction of the arrows
E and E 'in Figures 2-4). The developing device is transported inside the apparatus 100 by passing an opening shutter (inlet) provided in the image forming apparatus 100. The shutter 55 can rotate on an axis 54 in the directions F and F 'and, when the color developing device is transported inside the apparatus 100, the shutter is retracted to the position in which it is represented in broken lines by a coil, not shown, or the like so this does not interfere with the transport of the development device.

The store 150 also includes means
Y intended to move the enclosure (Figure 5 described below). The means Y as a whole move the enclosure 151 of the store up and down relative to the apparatus 100. Consequently, one of the partitioning shelves 151a-151d, which receives the development device containing the desired color, is moved by the means Y until it is aligned with the input of the image forming apparatus 100 constituted by the shutter 55 described above, (in the example of FIG. 1, the partition wall 151c is placed in alignment). Thus, a desired developing device can be transported to the interior of the apparatus 100. For example, when the image forming apparatus selects the developing device 13A in red, for example, the developing device 13C green, then placed in the apparatus 100, is first brought back to the partition 151c for partitioning the enclosure 151 by the means
X of displacement of the development device. During this return transport, the shutter 55 is retracted to the position in broken lines, that is to say the open position. When the device 13C for developing in green is brought back into the enclosure 151 of the store, means Z of discrimination, which will be described below with reference to FIG. 6,
confirm the presence of the device 13C for developing in green in the enclosure 151. When this is confirmed, the means for moving the enclosure begin to move the assembly of the enclosure 151 vertically relative to the apparatus 100 (in this case down) using the means Y, and stop when the partitioning shelf 151a supporting the development device 13A in red, desired, is brought into alignment with the inlet (shutter 55) of the device 100.

The development device 13A in red is then transported to the vicinity of the photosensitive drum 11 by the means X for moving the development devices shown in FIGS. 2 to 4 and it is thus placed in the position ready for the development of the image. the tent. The operation is the same when another color developing device located in the enclosure 151 of the store is chosen.

 Front and rear plates 101 and 102 of the image forming apparatus 100 have guide rails 111 and 112 which are fixed to their inner faces to support and guide the color developing device of the enclosure 151 of the store towards the photosensitive drum 11. The axis of the shutter 55 constituting the inlet of the apparatus 100 is fixed to the front and rear plates 101 and 102 by its opposite ends. When the shutter takes the closed position in which it is shown in solid lines in Figure 1, it is attracted to a magnet lock 551 provided on the device 100 in order to be maintained in the closed state. By cons, when it takes the open position in which it is shown in dashed lines, one end of this shutter 155 is applied in abutment against a support 104 of the apparatus 100 in order to keep the open state. At this time, the shutter is positioned by being attracted by a not shown coil, or the like, as described above. A microswitch MS is provided in the immediate vicinity of the position in which the shutter 155 is in abutment against the support 104 in order to detect the arrival of the shutter 55 in the open position.

A groove 13a is formed by ribs on an outer surface of the bottom of each of the devices 13A, 13B, 13C and 13D of development in chromatic color in order to engage with a tessellation roller of a control arm which will be described below after. The top wall of each of the developing devices has an opening 13b for the developer supply, which opening is covered with a cover 13c. In addition, the opposite end edges of a developing sleeve 13d are provided with rotating rollers. 13th stop intended to maintain a predetermined space between the surface of the developing sleeve 13d and the surface of the photosensitive drum 1 1
Below one of the guide rails 112, a control arm 130 is provided having a drive zone intended to transport a selected color developing device from the enclosure 151 of the store to the vicinity of the drum. photosensitive 11 of the apparatus 100. The control or drive arm 130 can rotate on an axis 131 mounted perpendicular to the guide rail 112. In addition, a long arm 132 is mounted on the side of the color developing device and comprises, at one end, an axis 133 carrying a pressure roller 134 which can be engaged with the groove 13a of the color developing device. At the other end of the arm 132, there is mounted a toothed wheel (toothed sector) 135 of worm. The worm gear has a central axis 131 and projects from a rear plate 102 passing through an opening provided in this plate. The worm wheel 135 is engaged with a worm 140 mounted on the image forming apparatus 100, outside the rear plate 102.

The worm 140 is integrally connected to a motor (direct current motor) 142 which can rotate in both directions, by means of a torque limiter 141. In addition, outside the rear plate 102 , a photo-switch 145 is provided for detecting the amplitude of the rotation of the arm 132.

The photo-switch 145 has the effect of detecting the instantaneous position of the arm 132 by detecting one or more notches of a disc 136 produced in one piece with the control arm 130.

 The operation of the control arm 130 will now be described. When instructions to change color, for example from green development devices 13C to red development device 13A, in the image forming apparatus, are produced, the motor 142 is released to facilitate rotation of the limiter torque 141, returned by spring, so that the pressure under which the device 13C developing in green is pressed towards the photosensitive drum 17 is released. Then the motor 142 begins to turn backwards so that the pressure roller 134 located at the end of the arm 132 pushes the wall of the groove 13a from the bottom of the development device 13C in green to move this device 1 3C in the direction E '. During this operation, the arm o132 pivots. When its end reaches the vicinity of the shutter 55 then open, the photo-interrupter 145 detects the notch of the disc 136. A predetermined period of time after, the motor 142 s' stopped. Thanks to these operations, the green development device 13C is returned to the partitioning shelf 151c of the enclosure 151 of the store.

When the device has returned to the store, the discrimination means Z shown in FIG. 6 confirm the presence of the development device 13C in green. Then, the enclosure 151 of the magazine is moved vertically, more particularly downwards, by the means Y of displacement of the magazine (FIG. 5) and when the shelf 151a carrying the developing device 13A in red, which is the desired development, is brought into alignment with the input of the apparatus 100, it stops. Then, the motor 142 begins to rotate forward, which rotates the arm 132 in order to move the development device 13A in red in the direction E via the pressure roller 134. it is introduced into the device 100 passing through shutter 55. The arm 132 rotates again and when the pressure roller 134 reaches the end of its range of motion, which is close to the photosensitive drum, the notch of the disc 136 actuates the photo- switch 145 for informing a controller of the image forming apparatus of the completion of transportation of the developing device 13A in red. Then, for a predetermined period, the motor 142 continues to rotate, which bandages a torque limiter spring 141, and pressure is applied to the pressure roller 134 at the end of the arm 132. The device 13A for development in red is thus brought into contact with the photosensitive drum 11 by means of spacing rollers 13e mounted coaxially with the developing sleeve 13b so as to maintain a space between the developing sleeve 13d and the photosensitive drum 11.

 The description will now relate to the means for moving the enclosure shown in FIG. 5. Two rails 200 are mounted on the rear plate 103 of the device 100 and extend approximately vertically and parallel to each other. 'other. The enclosure 151 of the magazine is engaged with the rails 200 so as to move vertically. The enclosure 151 is engaged with the rails 200 by means of guides 150a formed in the upper and lower positions of this enclosure. The guide 150a is provided with a roller 150b in order to reduce friction and the roller 150b rolls on the inner surface of the rail 200. A driving pulley 201a and a return pulley 201b, which constitute means of movement, are mounted so as to be able to rotate on the rear plate 103. A belt 202 passes over the pulleys 201a and 201b under a predetermined tension. An arm 150c, produced in one piece with the enclosure 151 of the magazine, is connected to a part of the belt 202. A central shaft of the lower pulley, which is the driving pulley 201a, is connected to a reversible motor ( pulse motor) 203 so that the enclosure 151 of the magazine moves substantially vertically 'relative to the device 100 along the rails 200 under the effect of a rotation of the motor 203. A microswitch 2 to 4 is mounted on the enclosure 151 of the store and is actuated by a part of this enclosure 151 when the device 13A for development in red, placed on the upper shelf of enclosure 151, is positioned. in alignment with the input of the device 101. The adjustment over time of the operations carried out by the means Y of displacement of the enclosure of the store has been described with the operation of the means X of displacement of the development devices and, by Therefore, it will therefore not be described again for clarity, except for the following.

The motor 203 begins to rotate in response to instructions from the control device of the image forming apparatus and it stops after turning a predetermined degree in a predetermined direction.

The direction and degree of rotation is based on how far the color development device, currently in place, is from the entrance to the device.

 In this embodiment, the movement mechanism consists essentially of a driving pulley 201a, a deflection pulley 201b and a belt 202. However, other types of mechanism can be used, for example a mechanism with light rack and pinion or a linear motor mechanism can be used.

 The means Y for moving the enclosure of the magazine also function in the case where the pressure roller 134 of the arm 132 is released from the groove 13a of the color developing device when the latter, housed in the device 100, is returned to the enclosure 151 of the store by the drive arm 130 in response to instructions for changing the developer. At the moment when the color development device is returned to the partitioning shelf of the enclosure 151 of the store, the pressure roller 134 of the arm 132 is engaged with the groove 13a of the color development device so that the arm 132 is in the position in which it cannot be retracted to the position which does not interfere with the vertical movement of the enclosure 151 of the magazine.

Consequently, to release the pressure roller 134 from the groove 13a in order to allow the arm 132 to retract, the means Y of displacement of the enclosure of the magazine drive the enclosure 151 slightly when it is confirmed by the means Z of discrimination that the color developing device has returned to enclosure 151 of the store. More particularly, the motor 203 rotates slightly to raise the enclosure 151 over a distance corresponding to the width of the pressure roller 134. Thus, the arm 132 can now retract to a position which does not interfere with the vertical movement of the '151 store enclosure. The displacement means Y execute only at this moment pedetermined operations to move the enclosure 151.

In this embodiment, the means
Y of movement of the store entrance raise the enclosure 151 to establish a removable engagement between the pressure roller 134 of the arm 132 and the groove 13a on the side of the color developing device.

However and as a variant, a rib constituting the groove 13a is produced so as to be able to pivot so that, when the color developing device is brought back into the enclosure 151, the rib pivots to release the engagement between the pressure roller 134 and the groove 13a, which allows the arm 132 to be retracted to the position not obstructing the vertical movement of the enclosure 151 of the magazine.

 Referring to Figure 6, we will now describe the means Z of discrimination intended to discern a color of the developer contained in a particular color development device when it is brought back to a predetermined partitioning shelf of the store 151 by the means X of displacement of the development devices, from the apparatus 100.

 The discrimination means Z comprise color detection switches (microswitches) mounted in the enclosure 151 of the magazine and a color detection projection provided in the color development device. A rear wall 155 of the enclosure 151 has three color detection switches 160a, 160b and 160c which are juxtaposed for each of the parts receiving a developing device, constituted by the partitioning shelves 151a-151d, respectively. Correspondingly, the rear wall of each of the color development devices 13A, 13B, 13C and 13D comprises one of three color detection projections 161a, 161b and 161c which are juxtaposed so as to actuate the respective switches 160a, 160b and 160c for color detection. Therefore, when the color developing devices 13A, 13B, 13C and 13D are inserted sufficiently to a predetermined position in the receiving parts of the developing devices, the projections 161a, 161b and Color detection 161c operate the color detection switches 160a, 160b and 160c. In response to signals from the detection switches, the color of the developer contained in the color developing device is determined, together with the detection of the presence or absence of the color developing device in the parts of corresponding reception of these devices.

In this example, the color and presence or absence detections are performed as follows. The signals from color detection switches 160a, 160b and 160c are represented by switches C1, C2 and C3, respectively, which signals are 0 when the switches are open and 1 when the switches are closed. The absence of the color developing device is detected by the fact that all the signals
Ci, C2 and C3 have the value 0. When C1 = 1,, C2 = 0 and
C3 = 0, it is then determined the presence of the development device in red, for example. In addition, when C1 = 1, C2 = 1 and C3 = 1, for example, blue is discriminated, for example. it is obvious, here, that the projections 161a, 161b and 161c of color detection are carried out according to the formula above.

 In this example, the color and the presence or absence of the color development device are detected by cooperation between the three color detection microswitches 160a, 160b and 160c provided in the parts receiving the developer of the enclosure 151 of the magazine and the three color detection projections 161a, 161b and 161c provided in the color development devices 13A, 13B, 13C and 13D.

However, the number of these switches is not limited to this example, but can be conveniently chosen by those skilled in the art. According to another variant, the color detection switches can be of the photo-interrupter type or the like instead of the microswitch type. It is requested here that the color discrimination and the presence or absence discrimination can be carried out when the color developing device is housed in position in the receiving parts of these developing devices.

 In this example, whether the color developing device is housed in position or not in the associated part intended to receive it is established by the use of the color discrimination means. However, other types of discriminating devices can be used by those skilled in the art.

The development device magazine of this embodiment is therefore equipped with means for detecting development devices associated with the respective parts housing these devices, and the following advantages therefore result.
(1) The development device store is kept informed of the identity of the development devices (colors) housed in the associated parts and, therefore, it is not necessary to enter this information during a stage. operation initialization. In addition, even if the power supply is temporarily interrupted, an undesired development device is not chosen, which could otherwise occur due to a memory failure.

 (2) it is possible to display which development devices (colors) are housed at this time in the parts intended to receive it from the store, on the display device of the imaging device in - using a control system for this device. it is also easy to provide means for displaying the development device which can be chosen from the store, independently of the control system of the image forming apparatus.

 (3) When a development device is removed, there is no need to pay attention to the receiving or receiving parts when it is reinserted.

 (4) The signal produced by the detection means of the development devices is taken as a signal indicating that the development device has fully returned so that, for example, the signal is used for controlling the following sequential operation: for example , in response to this signal, the means for moving the developing device and the means for moving the magazine are controlled from this signal.

 The number of development devices that can be accommodated in the enclosure 151 of the store is determined as a function of the space that the enclosure 151 of the store can occupy and which is located outside the device 100. Any number development devices can be put in place provided that the available space allows it.

 The development device housed in the enclosure 151 of the store is not limited to the device containing the chromatic colors as e>: pleated previously, but it may be an auxiliary development device containing the black pigment powder. In addition, the development devices which can be housed in the enclosure 151 do not necessarily contain developers of different colors but, on the other hand, several development devices of the same color can be housed if, for example, the color is often used .When the auxiliary development device in black is housed in position or more than one development device contains often used color developers, the developer ("toner") can be supplied to the empty device without stopping the imaging operation .

Consequently, the need to interrupt the image forming operation has been avoided, which is conventionally necessary when the developing device is empty or during developer. In addition, "toner" dispersion can be avoided during the "toner" refilling operation, thereby eliminating image deterioration which is otherwise caused by contamination of the guide plates or the like in the sheet transport passage.

 In this embodiment, the magazine for multiple development devices is an option without which the image forming apparatus can operate. In this case, the usual operation for forming a monochromatic image is carried out by means of the device 14 for developing in black mounted in the apparatus 100.

 The operations of feeding a color developing device will now be explained with reference to FIG. 7, which operations are carried out under the control of the means 400 for controlling the image forming apparatus.

 When a selection signal is introduced into the control means (step S1), it is first discriminated whether the chosen color development device is in place in the apparatus 100 or not, according to the information provided. by the means Z of discrimination (step S2). When it is confirmed that the selected development device is in place in the device 100 (answer yes), the sequence goes to step S3 where the color development device is translated to the working position by the means X, described above, of displacement of the development device. On the other hand, if it is discriminated that the color development device chosen is not located in the apparatus 100 (answer no) by means of the sensors C1 and C2, the sequence goes to a step S4 in which it is discriminated whether or not the chosen color developing device is in the magazine 150 according to the information supplied by the color discrimination means Z. When it is confirmed by the sensors C1 and C2 that the chosen color development device is in store 150 (answer yes), the sequence goes to step S5 where it is discriminated if a color development device is found or not in the transport passage of the device 100. If the answer is yes, the sequence goes to a step S6 where an empty shelf of the magazine 150 is brought into alignment with the shutter 55 (entry of the device 100) by the means Y of moving the magazine, then in a step S7, the color developing device located in the transport passage of the device 100 is brought back to the empty shelf by the means X of moving the developing devices and, then in a step S8, the development device chosen in the store 150 is brought to the level.

supply by the means Y for moving the magazine. In step S9, the selected color development device is introduced from the magazine 150 into the apparatus 100. When the switch C1 detects that the selected development device is now in the development standby position, the color development having been introduced into the apparatus is brought to the working position in step S10. here, in steps S9 and S10, the means
X of movement of the development device intervene. On the other hand, if in step S4, it is discriminated that the development device in color chosen is not in the magazine 150 (answer no), the sequence goes to a step S11 in order to display the impossibility of development and the need to set up the development device in the magazine 150. If in step S5, it is determined that no color development device is in the passage of the apparatus 100, the sequence goes to step S8 where the color developing device chosen in the magazine 150 is moved to the power input.

 After the complete execution of steps S3 and S10, the development operation is executed in step S12 and, in step S13, it is determined whether it is necessary for the operation to continue.

If this necessity exists (answer yes), the reaction command is executed, while in the opposite case (answer no), this program ends.

 The control means 400 are equipped with an interface for transmitting a signal from the main device 100 to the store 150 of development devices and for transmitting a signal from the store 150 to the main device.

 As previously described, according to this embodiment, a developing device selected in accordance with a selection signal is automatically taken out of the developing device store and is automatically transported inside the device to place the training device d images in condition of executing the desired image formation operation, the installation of the requested development device being able to be carried out without requiring manipulation on the part of the operator and in a precise and rapid manner. In addition, it is possible to prevent the device from becoming bulky by being equipped with several development devices.

 FIG. 8 illustrates a connection part between the apparatus 100 and the magazine 150. In the main body of the image-forming apparatus, there is formed a passage 500 for transporting developing devices consisting of guide rails 112 to establish a connection between the functional development position in the vicinity of the photosensitive drum 11 and the input 22 of the development device, closed or open by the shutter 55.

 The magazine 150 for developing devices comprises a base element 7 in the form of a flat plate having an inlet 22A for introducing a developing device into predetermined entry positions and a storage enclosure 151 which can be moved little by little. vertically close by a drive mechanism, not shown, relative to the base element 7. The front end (left side in this figure) of the enclosure 151 is open, and the base element also assumes the cover function for enclosure 151.

 As shown in Figures 8 and 9, lugs (latching means) 211 are fixedly mounted on the base element 7 of the magazine 150, on the front and rear sides of the supply inlet 22A to correctly position the input 6 for supplying the developing device with respect to the input 2 for developing device in the vertical and horizontal directions. The lugs 211 have tapered ends.

 I. when the magazine 150 for developing devices is to be mounted on the main body 100 of the image-forming apparatus, the magazine 150 is arranged so that the horizontal pins 211 are aligned with horizontal holes formed on the side and on the other side of the input 2 of the development device, in accordance with the lugs 211, then the magazine 150 is moved so that the lugs engage in the holes. Then, the base member 7 is attached to the main body 100 by removable removal means such as bolts or the like.

 In this way, the supply opening 22a of the magazine 150 for developing devices is positioned relative to the input 22 of the developing device of the apparatus 100 with great precision. Therefore, a color developing device selected from store 150, namely the green developing device 13D in the example illustrated, can be gently transported to the feed opening re 22a and is still transported in smooth entry from 2 to the working position by the means of transport located in the apparatus 100 (rack 511 and pinion 52), so that the desired development device can be brought into the working position without problem . The lugs 211 and the holes 221 can be interchanged.

 With reference to FIGS. 9 and 10, a structure will be described making it possible to adapt to a vertical and horizontal deviation, in a transfer position between the image forming apparatus 100 and the store.

As shown in Figures 5 and 21, if there is a gap between the guide rails 27 of the developing device housing part which receives the selected color developing device and the guide rails 28 of the transport passage 50 of the apparatus 100 after the enclosure 15 of the store has been suitably moved by the mechanism Y (a vertical gap is shown in this figure, but the gap can be horizontal), the color developing device cannot then be moved smoothly, especially when transported from the store enclosure to the device 100.

 To avoid this problem, the guide rails 28 of the device 100 and the guide rails 27 of the store enclosure are flared in order to present an enlarged sliding space on the respective connection sides. The guide rails 27 and 28 are in the form of a U-shaped profile with which are intended to engage associated projections formed on the lower surface of the developing device, on both sides of the latter, and the walls side 272 and 282 and the bottom walls 281 and 271 of the profile are inclined to form a progressively widening guide space, therefore, even in the case of horizontal deviation and / or vertical deviation between the guide slide 27 of apparatus 100 and guide rail 28 of magazine 150, the color developing device is firmly guided by the inclined surfaces so that it can be transferred from the magazine to the device or from the device to the store, for sure.

 With reference to FIG. 11 considered with FIGS. 8 and 9, the description will relate to means P of return or pressure of the developing device. In FIG. 11, the solid lines show the state in which the means P for pressing the developing device are in the position in which they exert pressure on the developing device, while the dashed lines illustrate the state in which these means are released.

 The pressure means P are arranged below each of the guide rails 112 in the immediate vicinity of the working position of the apparatus 100, and they execute their pressure and release operations in association with operations carried out by the means transport of the development device. As described in more detail below, the release or release operation is performed when color change instructions are produced in the image forming apparatus, and the means of transport of the developing device begins to operate, while the restoring pressure operation is performed when it is known that the transportation of the developing device within the image forming apparatus, by the transportation means, is completed.

 The pressure means P comprise a pressure lever 21 which can act on a lower part of the rear surface of the development device (development device 13A in red, for example) in order to push or return the development device towards the exterior surface of the photosensitive drum 11, a cam 212 intended to rotate the pressure lever 21 and a return spring.

 The pressure lever 21 is mounted so as to rotate on a fixed axis 213. The cam 212 is fixed on a rotating axis 211. When the cam 212 rotates under the effect of the rotation of the axis 211, the lever 21 of pressure rotates on the fixed axis 213 while being in contact with the surface of the cam located behind the lever 21. When the rotary axis 211 rotates so that the cam 212 takes the position located most to the left, the processing lever 21 moves upwards. When the rotary axis 211 continues to rotate from this state so that the cam takes the rightmost position, the pressure lever 21 is moved down under the action of the spring, as shown in FIG. 11 .The maximum range of rotation, when the pressure lever 21 is in the high position, is limited by a limiting stud (stop 175 provided for safety in the event of an emergency). Thanks to this structure, the pressure lever 21, when it performs a pressure operation, pushes the developing device under a predetermined pressure in the transport passage, while, when it is released, it is retracted below of the guide slide 112, that is to say it is retracted down the passage 500. Consequently, the developing device is placed in the working position by the pressure means in a safe manner and with great precision and, in addition, the horizontal movement of the developing device can be carried out smoothly.

With reference to FIGS. 11 and 14, the structure by which the development device can be brought into position with greater precision with regard to the pressure operation towards the development position and the means of transport of the development device will be described. (especially in the image forming apparatus). In FIGS. 11 and 12, the image forming apparatus comprises the main body X to which the magazine is juxtaposed
Y to development devices. The magazine Y contains on the shelves several development devices 13A, 13B and 13C containing "toners" of different colors. The magazine Y can be moved substantially vertically to place a desired development device, for example the device 13A, facing a input of the main body X, and so that the developing device is transported to a rest position (position in dashed lines in FIG. 11) adjacent to the photosensitive drum 11.

 In Figure 11, the following structure is provided on each side with respect to the transport direction of the developing device. Pressure means P have the function of pushing the developing device 13A, placed in the rest position, towards the photosensitive drum 11 in order to bring it into contact with it. The pressure means P comprise a pressure cam 212 fixed to a drive shaft 211 which can be rotated by a source of motive force, and a pressure lever 21 journalled on an axis 21 3 and kept in contact with the pressure cam 212 by a spring. Transport means 53, intended to transport the development device between the rest position and the magazine Y, will be described. A mad gear 524 is fixed to a drive shaft 528 driven by drive means not shown, and a lever 526 is mounted so as to be able to rotate on the drive shaft 528. One end of the lever 526 carries a first toothed transport wheel 522 which is constantly engaged with the idler gear 524. The other end of the lever 526 is connected to an operating arm of a reel 525 and is always returned clockwise by a spring 523 mounted on the side of the first toothed transport wheel 522. The magazine Y is provided with a second toothed wheel 51 for transporting at the level of each of the housing parts, which wheel can engage with a rack 511 formed on the left and right parts of the upper surface of each of the devices. 13A, 13B and 13C. The source of motive force for the second toothed wheel 51 of transport can be common to that of the first toothed wheel 522 of transport, or independent of this one.

The description will now relate to the operation of vertically moving the store.
Y to bring a selected development device, for example the device 13A, into the rest position.

First of all, the second toothed transport wheel 57 rotates to move the developing device 13A towards the main body 13Y by means of the rack 511. When a microswitch C3 mounted in the main body X detects the arrival of the 13A development, the coil 525 is controlled so as to rotate the lever 526 in the opposite direction to that of clockwise. Thus, the first toothed transport wheel 522 moves to the position in which it is shown in phantom in Figure 11 in order to be brought into engagement with the created Maillera 511 of the development device 13A. understand from the relative positions shown in the figures, there is a period of time during which the two gears 51 and 522 are engaged with the rack 511 of the developing device 13A, so that the transport is stabilized. The development device 13A continues to be advanced towards the rest position (dashed line position in FIG. 11) in which it is stopped. When the stop is detected and the coil 525 is de-energized, the. lever 526 rotates clockwise under the action of spring 523 so that the first transport wheel 522 is released from the rack 511 to take the position in which it is shown in solid lines. pressure means then rotates from the dashed line position to the solid line position in order to rotate the pressure lever 21 which pushes the developing device 13A towards the position shown in solid line, that is to say the position functional development, the development device then being applied against the photosensitive drum 11 under a predetermined pressure. Thus, the developing device 13A is placed in the position allowing the latent image to be developed on the photosensitive drum 11.

 The main body X is equipped with an additional developing device (not shown), for example a developing device in black which is always positioned in the immediate vicinity of the photosensitive drum. When this development device in black is used, the development device 13A in red, described above, must be retracted to its rest position. To this end, the pressure cam 212 is turned towards the position in phantom in such a way that the pressure lever 21 rotates clockwise to release the pressure applied to the development device 13A, the latter being retracted to the rest position by conventional means of displacement, following the release of the pressure. When the development device 13A is brought back to the store Y, it is first discriminated whether or not the development device 13A is in the rest position, using the microswitch C3. If this position is determined, the coil 525 is controlled in order to rotate the lever 526 anticlockwise and to make the first toothed transport wheel 522 mesh with the rack 511.

Then, under the effect of a reverse rotation of the first toothed transport wheel 522, the transport of the developing device 13A in the opposite direction begins. When the developing device 13A reaches the magazine Y, the backward transport is continued by the second toothed wheel 51 of transport. When the microswitch 150B is actuated, the rearward transport is completed and stopped.

 In this embodiment, when the developing device 13A is in the image forming apparatus, more particularly in the developing position, the first toothed wheel 522 of the transport means 52 is not engaged with the rack 511, but it meshes with rack 511 when the developing device 13A is in the rest (standby) position. As a result of this clearance between the first toothed transport wheel 522 and the rack 511, the transport means 52 and the pressure means do not interfere with each other. As a result, the developing device can be placed precisely in the image forming apparatus and is contacted with the photosensitive drum 11 under appropriate pressure.

 Furthermore, in this embodiment, the source of motive force of the first toothed transport wheel 522 is not subjected to an unnecessary load and, when the developing device 13A returns to the rest position, the toothed wheel 522 and rack 511 can be suitably engaged.

 A modification of the second embodiment described above will now be discussed with reference to FIGS. 13 and 14. This modification relates to the force transmission system for the rack and the toothed wheel of the developing device and the toothed wheel of the store of the structure of FIGS. 11 and 12. A drive shaft F1 is actively connected to a source of motive force not shown.

The driving force is transmitted to a toothed wheel 51A via the drive shaft F1. The toothed wheel 51A is mounted on a plate 51F. On the plate, toothed wheels 51E and 51G are mounted on a first side of the toothed wheel 51A, and toothed wheels 51H and 51C and the second toothed wheel 51 of transport are mounted on the opposite side. In addition, on the plate 51, one end of a link 52C is connected to a coil, not shown. The plate 51F can rotate in a horizontal plane under the action of the coil. When the plate 22 is in the position shown in solid lines in FIG. 14, the toothed wheel 51G is engaged with the wheel 51D, while the second transport gear 51 meshes with the rack 511 formed on the side wall of the developing device 13A. The rotation of the toothed wheel 51G is transmitted to the rotating shaft F by means of the toothed wheels 51D, 51D ′ and of a bevel gear F21, and it is also transmitted to the first transport toothed wheel 52 by means of toothed wheels 51C (51I), 52B and 52A. The first toothed transport wheel 52 can mesh, in the main body of the image-forming apparatus, with the rack 521 formed on the upper surface of the developing device 13A. Similar to the case of the first embodiment, when the developing device 13A is in the rest (standby) position, the first transport gear is moved to a position in which it meshes with the rack 521, but, when the developing device is in the working position, the first toothed transport wheel 52 is moved so as to engage with it.

 When the developing device 13A is transported between the main body X and the magazine Y, the coil is excited to rotate the plate 51F towards the position in solid line of FIG. 14, so as to transmit the driving force of a source of motive power, not shown, at the first toothed wheel 52 for transport and at the second toothed wheel 51 for transporting the developing device 13A by means of the racks 521 and 511. Once the transport is completed, the spool is de-energized to rotate the plate 51F to the position shown in phantom. Then the meshing between the second toothed wheel 51 of transport and the rack 511 is released.

 As described above, in this embodiment, the developing device is correctly placed in the operational developing position and it is further applied under appropriate contact pressure against the image bearing member.

 Furthermore, in this embodiment, the length of the rack 521 on the top, or alternatively on the bottom surface of the developing device, and of the rack 511 located on its side, measured in the direction of transport of the developing device. development, is greater than a distance L1 between a position C'1 of engagement between the rack 511 and the toothed wheel 51, and a position of engagement C'2 between the rack 521 and the wheel 52 (Lî <L) for further improve transport between the imaging device and the store with development devices.

 With reference to FIGS. 15 to 17, a structure will now be described making it possible to tolerate a difference in position of the connection part between the image forming apparatus and the magazine with development devices used with it, in order to improve transfer between them. The characteristic of this embodiment resides in an intermediate element intended to assist in the transfer of the developing device, arranged in the junction between the magazine guide and the guide of the main body of the image forming apparatus. In this embodiment, an intermediate plate and an intermediate roller are arranged opposite the inner surface of the developing device. In FIGS. 15 and 17, the intermediate element is provided on the main body of the image-forming apparatus, while in FIG. 16, it is provided in the magazine.

 In FIG. 15, the intermediate plate 24 is arranged to guide elements of both the main body and the magazine in order to guide the projection of the developing device. The function of the intermediate plate 24 is similar to that of the flared guide part 272 and 282, explained with reference to FIG. 9, which is better than this structure from a practical point of view.

 FIG. 16 shows an example in which guide rollers 2 are mounted so as to rotate on the corresponding partition shelves 151A151D of the enclosure of store Y.

 FIG. 17 shows a structure making it possible to tolerate the horizontal deviation, the guide rollers 24 being arranged on both sides of the guide slides of the main body X.

 The guide rollers 24 can be in the form of rollers which can rotate freely or they can be driven in rotation by a reversible pulse motor.

 Thanks to these structures, the transport between the main body X and the store can be carried out smoothly, which improves the quality of the advance operations of the development devices.

 Referring to Figures 18 to 25, the relationship between the main body of the imaging apparatus, the magazine with developing devices, and the sheet feed means, in particular manual feed means, will now be described. advance or sheet feed. This embodiment is particularly advantageous when a sheet advance means is arranged below the magazine, but it is also advantageous in the other case to prevent the developer from dispersing and falling.

 In FIG. 18, the image forming apparatus is equipped with means allowing manual advance of the recording medium, in addition to the embodiment shown in FIG. 1. The recording medium or sheet manually advanced on the feed or manual feed tray 66 is received in the image forming apparatus by a feed roller 64. The sheet is then advanced towards framing rollers 23 by means of guide plates and pairs of rollers. The manual supply device 67 is made in one piece with the magazine B with developing devices, in its lower position. In addition, an element 70, mounted on the magazine with which it is made in one piece, is intended to receive the developer falling from the development device. The element 70 extends from its base, which is secured at the store, to a free end, and it is tilted slightly upwards from its base end, as shown in FIG. 18. The receiving element 70 has the effect of preventing manual feeding into recording sheets to be contaminated by the developer falling from the development device moved for transfer between the main body of the device and the store, since this element 70 receives the falling developer. Figures 22 to 25 show modifications.

 In FIG. 18, the manual advance device and the element 70 for receiving the falling developer are fixed below the range of vertical movement of the enclosure 150 of the magazine. However, when the number of developing devices housed in the magazine Y is large and that, consequently, the vertical movement range of the enclosure 150 of the magazine is longer, or when it is desired to position the device in advance manual as high as possible, the manual advance device 60 and the element 70 for receiving the falling developer are advantageously arranged in the range of movement of the enclosure 150 of the magazine.

 The embodiment of Figures 22 and 23 satisfies this requirement. In this embodiment, the manual feed plate and the receiving element 70 can be moved, but without a mechanism intended to drive them. As can be seen in FIGS. 22 and 23, the plate 65 for feed or manual feed and the element 70 for receiving the developer are turned by coming into contact of the element 70 for reception with the magazine Y descending as far as in a recess of the main body, which recess is intended to house the receiving element 70 and the plate 65 for manual advance. These elements being housed in the recess, they are towed so as not to impede the movement of the magazine Y with development devices. More particularly, the plate 65 for manual advance and the element 70 for receiving the falling developer can rotate integrally on an axis 66 as far as in the recess 67 of the main body X. They are normally returned by a predetermined moment exerted by return means not shown, in the direction indicated by an arrow in FIG. 22, that is to say in a direction such that the plate 65 for manual feeding and the element 70 for receiving are in the rest position, that is to say protrude from the recess. In the state shown in FIG. 22, one end 70a of the receiving element is in abutment against a wall 67a of the recess 67. The moment value is then determined so that the plate 65 for manual feeding does not not rotate down when one or more record sheets 17 are placed thereon.

 If necessary, the magazine Y moves down as shown in Figure 23.

At this moment, the lower end of the magazine Y with developing devices is brought into contact with the receiving element 70 which is then turned, with the plate 65 for manual feeding, on the axis 66 in the direction indicated by an arrow in this figure so that the element 70 and the plate 65 are housed in the recess 67.

After the desired development device 13A has been placed in the main body
X of the apparatus, the magazine Y with developing devices is moved upwards to the initial position shown in FIG. 22. Then the plate 65 for manual feeding and the element 70 for receiving go up by pivoting under the moment exerted by the return means, not shown, in order to return to the working position shown in FIG. 22, thus allowing a manual feeding operation.

As a variant, the operation of returning the magazine Y to the position of FIG. 22 can be carried out to allow a manual feed operation only when the manual feed is chosen on the control panel of the training apparatus. images.

 In FIG. 24, a recess or a recessed part is formed in a lower portion of the main body, at the same level of position as in the arrangement of FIG. 18, and an element 70 of receiving the falling developer which is in the form of a container. An inclined sheet 70a of elastic resin extends from the receiving container 70. The falling pigment powder or "toner" is collected in the container along the elastic sheet 70a. The free end of the sheet 70a of elastic resin is arranged so that, when the magazine Y with developing devices arrives in its lowest position, this free end of the sheet 70a of elastic resin comes into contact with the bottom of the This store. The "toner" present on the elastic sheet 70a is then effectively collected in the container 70 by the resulting vibration.

 In FIG. 25, the bottom of the enclosure 150 of the magazine Y with developing devices is produced in the form of a container 70 intended to receive the falling developer, container from which a similar sheet 70a of elastic resin leaves. Thus, the falling "toner" is collected in the container 70 along the elastic resin sheet. It is preferable that the elastic resin sheet 70a touches the main body.

 Referring again to FIG. 19, the description will relate to a reversing mechanism D making it possible to selectively transmit a driving force from a single source of motive force (motor 493) to the device 67 for manual feeding or to the magazine Y to development devices. The motor 493 comprises an output shaft on which is fixed a toothed wheel 494. Its rotation is transmitted either to a toothed wheel 643, or to a toothed wheel 207 by means of a toothed wheel 495 and a toothed wheel tilting 208. The tilting gear 208 is mounted on an arm 206, close to its end, and the arm has the shape of an "L" and can rotate on a shaft 205 of the gear 495 in the direction indicated by arrows P1 and P2.

Another arm 491B of "L" shape, which can pivot in the direction indicated by arrows N1 and N2 on an axis 491 C, is connected to a coil 49 by one end. The other end of the arm 491B is engaged with the other end of the arm 206. The arm 491B is normally returned in the direction N1 by the action of a spring 492 mounted on one end of the arm 491A which is fixed in the center of the arm 491B, so that the arm 206 is normally returned in the direction P1 and that, consequently, the toothed wheel 208 is normally engaged with the toothed wheel 207 as shown in solid lines.

 The toothed wheel 207 transmits the driving force of the motor to the development device magazine or to an automatic development device changer Y. Furthermore, the toothed wheel 643 has the effect of transmitting the driving force to the device 67 for manual feeding. As shown in FIG. 20, a wheel 642 with conical teeth is fixedly mounted on the other end of the shaft 64B of the toothed wheel 643 and meshes with another conical toothed wheel 641 to which two feed rollers 64 are connected fixedly.

 Consequently, when the reel 200 pulls the arm 491 in the direction M2, the pivoting toothed wheel 208 moves in the direction P2 through the arms 491 and 201 in order to mesh with the toothed wheel 463, following whereby the rotation of the motor 493 is transmitted to the bevel wheels 642 and 641 by means of the toothed wheels 494, 495, 208, 207 and of the shaft 64B, as well as to the feed rollers 64 by means of the wheel 215. A recording medium or sheet 17 placed on the manual feed tray 66 is thus inserted into the main body A.

 With reference to FIGS. 21 and 26, the description will relate to another example of the automatic changer Y of development devices. The automatic changer Y includes a magazine enclosure 150 with development devices intended to accommodate several development devices 13A, 13B and 13C, and drive means C intended to vertically move the enclosure 150 in one piece (in the direction Y-Y ') as well as transporting the selected development device 13B, for example to the image-forming station, in a direction X-X'.

The drive means C can be applied to the arrangements shown in Figure 14 and in Figure 32 which will be described below. As shown in Figure 21, the drive means
C comprise a coil 491 which comprises a rod 491A which can be moved in the directions indicated by arrows aa 'in FIG. 21. A pivoting lever of "L" shape is mounted so as to be able to rotate on an axis 107 at one end free from rod 491A.

One end of the pivoting lever 105 pivots on an axis 105a of the toothed wheel 105 and, in the immediate vicinity of the other end of the lever 106, a toothed wheel 108 is mounted so as to rotate in a horizontal plane, the wheel 108 being normally engaged with the toothed wheel 105. The latter meshes with the toothed wheel 207 (FIG. 19) adjacent to one end of the reversing mechanism D.

 In close proximity to the toothed wheel 108, toothed wheels 111 and 51A are mounted so that they can rotate in a horizontal plane and can be selectively engaged with the toothed wheel 108. An endless screw 114 is fixed to a shaft turning 113 carrying the gear 111 as shown in the figure. The worm 114 meshes with a small rack 115 extending approximately vertically on one end of the enclosure 150 of the development device store, near the main body. The toothed wheel 51A is engaged with a toothed wheel 51 in order to move the developing device in the direction X-X 'via the toothed wheels 51H and 51I which can rotate in a horizontal plane.

The toothed wheel 51 meshes with a rack 511 formed on one side of the developing device 13B.

 The pivoting lever 106 can pivot on the axis 105a of the toothed wheel 105 in the direction of the arrows b-b '. This pivoting lever 106 is normally returned by a spring 120 in direction b and, when the coil is not excited, the toothed wheel 108 which it carries is engaged with the toothed wheel 111, as shown in FIG. 21.

 Then the motor 208 is rotated forward by control means not shown, the pivoting toothed wheel 210 of the drive mechanism D being engaged with the toothed wheel 207, as shown in FIG. 19, and, the toothed wheel 108 shown in FIG. 21 being engaged with toothed wheel 111, the rotation of the motor is transmitted to the endless screw 114 by means of toothed wheels 207, 204, 210, 206, 105, 108 and 111 and of the shaft 113 to rotate the worm 114 by means of which the enclosure 150 of the magazine, equipped with the rack 115 in engagement with the worm 114, is moved in the direction Y, for example upwards .

If the motor is rotated in the opposite direction, the enclosure 150 of the magazine moves in the direction
Y ', that is to say down. In this way, the enclosure 150 of the magazine is raised and lowered and, consequently, a developing device having a developer of a desired color, chosen from the developing devices located in the enclosure 150 of the magazine, is moved so as to be opposed to an input, not shown, of development device, presented by the main body
X, when the motor 493 is stopped in this position.

Then, the control means 400 of FIG. 6 control the coil 104 to retract the rod 104a in the direction a '. The lever 106 then pivots on the axis 105a in the direction b ', at the same time as the toothed wheel 108, against the force of the return spring 120 and, as shown in FIG. 26, the toothed wheel 108 is tilted so to pass from its position engaged with the toothed wheel 111 to that engaged with the toothed wheel 51A. When the motor 493 is rotated forward, in this state, the rotation is transmitted to the toothed wheel 51 of drive in the direction X via the toothed wheels 207, 105, 108, 51A, 51H and 51I, so that the toothed wheel 51 is driven, after which the development device equipped with the rack 511 in engagement with the toothed wheel 51 is transported in the direction X as far as the image forming station of the main body X of the imaging device. Furthermore, if the motor 493 is rotated in the opposite direction, the drive device is returned from the image forming station, in the direction X ′, to the enclosure 150 of the magazine with development devices.

 By repeating the operations described above, it is possible to automatically change the development device.

 As previously described, in this embodiment, the automatic developer device changer and the manual feeder cannot operate simultaneously and, therefore, the scattering of "toner" or the image disturbance, which may result movement of the developing device can be avoided, as can an erroneous image forming operation, thereby obtaining good quality images.

 It is possible to provide separate drive means for vertically moving the enclosure 150 from the development device magazine, for transporting the chosen development device 101, from the store enclosure to the image forming station, and for the manual feed device, but at least three reversible pulse motors must be used, which results in increasing the cost, complicating and making the device bulky and complicating the control system. This is the reason why the embodiment described above is advantageous in that the driving force is transmitted firmly to suitable means and in a synchronized manner so that the developing device is protected from any risk. The control system for driving the apparatus according to the present invention can be presented as follows. It includes a source of motive force intended to move the development device magazine so that it accommodates several development devices, the source of motive force also being used to advance the selected development device towards the imaging station. , and it also comprises reversing means intended to reverse the force transmission between the source of motive force and the drive element of the magazine with development devices, and the source of motive force and the drive element for transporting the developing device. In accordance with this structure, the automatic developing device changer can be simplified and its size can be reduced with, for advantage, the possibility of preventing the transmission of the driving force in both direction (if the force is transmitted in both directions, the magazine enclosure or the developing device is damaged).

 The last described type of horizontal drive mechanism for the developing device (Figures 9-14, 15, 17, -21 and 32) is advantageous compared to the first described type of the horizontal drive mechanism (Figures 2- 4), because in the latter type, the driving force is applied to the two lateral sides of a developing device with respect to its direction of transport, which stabilizes the transport, unlike the first case in which the force of drive is applied in a single line and therefore, if a rack and pinion mechanism is used for force transmission, the force applied to the respective sides is substantially the same.

Referring again to Figures 8 and 21, the features of the drive mechanism are as follows
(1) practically the same driving forces are applied to the respective lateral sides of the developing device with respect to the direction of its transport
(2) for this purpose, the first and second force transmission means are designed to apply substantially the same driving forces to the lateral sides of the device
(3) the developing device is equipped with first and second elements for receiving the driving force on its two lateral sides.

 Thanks to these features, the development device is transported while receiving substantially the same driving forces on its two lateral sides. Therefore, the developing device can be transported stably and smoothly, without being tilted relative to the transport direction.

 Furthermore, with reference again to FIG. 8, the lever 27 of "L" shape has the function of blocking the developing device housed in the magazine in the state shown in FIG. 8, and it can be actuated by the coil 28 to be retracted from the passage of the development device.

 As shown in FIG. 12 and in FIGS. 33 and 36 which will be described below, the horizontal drive mechanism, intended to drive the development device in a horizontal plane in the magazine and in the apparatus for forming images, is provided on each of the lateral sides of the developing device with respect to the transport direction of the latter so that substantially the same driving force is transmitted to both sides by dividing the horizontal driving mechanism into first and second means of transmission. The first and second transmission means can be provided on the upper and lower surfaces, respectively.

In all cases, the first and second transmission means are formed substantially by the same rack and pinion mechanism, substantially of the same design (511-51, 521-52), so that the same driving forces are transmitted. on both sides.

The gear and rack mechanism smoothly transports the development device and the guide means (concave) and the intermediate elements further stabilize the transport.

With reference to FIGS. 27 to 31, a safety mechanism used with the apparatus according to the invention will be described. In the previously described image forming apparatus, the drive mechanism for the vertical movement of the developing device magazine is of the bidirectional type and, therefore, when the engine stops, for example as a result of If the power supply fails, the source of motive power is unintentionally driven by the weight of the developer magazine, which results in the magazine falling. In this embodiment, a control element is provided to limit the movement of the magazine. Due to the presence of the control element, the magazine cannot fall under the effect of its own weight, even if the motive power source stops working for one reason or another, because the control element has the effect of allowing the transmission of the driving force between the source of motive force and the magazine only in one direction. The drive means C comprise a pulse motor M which can be started in both directions by an element
O motor control, and the output shaft of the pulse motor M is oriented upwards, as shown in the figure. In the immediate vicinity of its end, a worm 114, assuming the function of the control element, is formed to establish the unidirectional nature of the transmission of force from the pulse M motor. The worm -114 does not allows a force transmission from the pulsed motor M to the magazine Y. The worm 114 is still engaged with the rack 115 formed on the end of the magazine Y.

 Thanks to this worm mechanism, the force transmission can only take place under the effect of a rotation of the worm 114, which rotation is transformed into a linear movement of the rack 115, but the transmission in the opposite direction, the linear movement of the rack 115 in a rotational movement of the worm 114, is prevented.

Therefore, even if the pulse motor M stops due to a power failure or the like during the control of this motor M, the worm 114 is not rotated by the rack 115 due to the weight of the magazine, so that magazine Y cannot fall under the effect of its own weight.

 Referring to Figure 28, there is shown a top plan view of a modification to the arrangement of Figure 27. In this modification, a stepped gear mechanism is used in the drive means C 'for move magazine Y vertically. The resistance resulting from the reduction function of the stepped gear mechanism is used to prevent magazine Y from falling due to its weight.

 The pulse motor M constituting the drive means C 'comprises an output shaft 114G which carries toothed wheels 114A and 114F of large and small diameter, fixed to this shaft. The toothed wheel 114F of small diameter meshes with a toothed wheel 114E of large diameter mounted so as to rotate on an axis 114G 'fixed to the main body X. In addition, the axis 114G' carries a toothed wheel 114C of small diameter which can rotate freely and this toothed wheel 114C is engaged with a toothed wheel 114A fixed to a long shaft 114B extending parallel to the axis 114G '.

A toothed wheel 114A of the same diameter as the first toothed wheel 114A cited, is fixed to one end of the shaft 114B and these toothed wheels 114A and 114A mesh with racks 115 and 115 extending approximately vertically on both sides from magazine Y. The rotation of the motor M is transmitted to the toothed wheel 114A, with the reduction in two stages (in this embodiment, the reduction is approximately 1/40). When the impulse motor M stops due to a power failure or the like, the weight of the magazine
Y tends to rotate the toothed wheels 114A and 114A in engagement with the racks 115 and 115; however, the transmission of force from the toothed wheel 114A to the pulse motor M involves an increase in speed and, consequently, meets a great resistance opposed by the transmission. Consequently, the toothed wheels 114A and 114A do not turn, of so that the development device magazine Y cannot fall under its own weight.

 Referring to Figures 29 and 30, a stop is used for the same purpose. The stop can be engaged with the rack 115 (figure 29) and the bottom of the enclosure 150 of the magazine (figure 30). The stop is moved, in the event of a power failure or the like, by the control means 117 which cause movement of the axes 116 and 118 by de-energizing a coil in order to prevent the enclosure of the magazine from falling.

 In FIG. 31, a mechanical stop 119 is arranged so as to bear against the bottom of the enclosure 150 of the magazine when this magazine takes the lowest position for transporting a development device. The stopper is placed in the main body of the image forming apparatus.

By this means, the magazine is firmly prevented from falling under the effect of its own weight even if the source of motive power fails for one reason or another.

 Referring to Figure 32, the description will now relate to the structure allowing additionally the developing device to be mounted in or disassembled from the main body of the imaging apparatus, as well as to another advantageous structure of the development system.

 In this embodiment, the means of transporting the developing device inside the main body of the image forming apparatus, which means are intended to transport the developing device to the image forming station, consist of a rack formed on the upper or lower surface of the developing device, a toothed wheel which can be engaged with this rack and a motor intended to drive the toothed wheel.

This structure makes it possible to easily mount or dismount the development device.

 The drive mechanism inside the magazine comprises a toothed wheel 51 which can be moved by a lever 51F connected to the coil P3, between the working position in which it is engaged with the rack 511 and a cleared position of withdrawal , and the toothed wheel 51I which can turn on the fixed axis F1 to transmit the driving force there. The drive mechanism operates in the synchronized manner described above. The drive mechanism, inside the main body of the image forming apparatus, is disposed above the developing device. In the main body, guide passages 80 and 81 extend in a direction perpendicular to the direction of movement by which the developing device approaches and moves away from the imaging station. drive passages which is close to the photosensitive member 11 is narrower than the other. These passages are associated with projections shown in broken lines, formed on the bottom of the developing device, and they assume the function of anti-adjustment means to ensure that the side of a developing device, comprising the developing sleeve, is facing the photosensitive drum 11.

Compared with the structure shown in Figure 9, the developing device 13B can be retracted from the main body of the device
X only by being pulled outwards (downwards in FIG. 23) along the guides 80 and 81, without the drive mechanism (coil M1 and toothed wheel 52) performing a major release operation. The mechanism of the image forming apparatus can therefore be simplified.

 In Figures 32, 14 and 21 and in Figure 34 which will be described below, it is not necessary to provide the means of transport in the store for each of the housing shelves, unlike the arrangement of the figure 11. The removal of the guide means can be carried out using a simple structure and by a slight displacement of the toothed wheels 51 in the longitudinal direction of the developing device. Consequently, the magazine Y can be made to smaller dimensions and in a more simplified manner. This leads to a smaller and simplified structure of the image forming apparatus equipped with the magazine Y with development devices as a whole.

 Referring to Figure 34, where a developing device 14 in black, which is usually used most often, is provided below the transport passage of the developing device, i.e. below the device 2A of development in this figure1 the drive mechanism inside the image forming apparatus is preferably arranged above the development device 2A because, otherwise, that is to say when the mechanism drive is arranged below the developing device 2A, the developing device 14 must be placed even lower, which influences the imaging conditions and causes image deterioration.

 FIGS. 35 and 36 represent an arrangement in which a hopper H, intended for recharging the developer device 14 in black in developer, is arranged so as to avoid any discomfort with the first means of transport 52.

 In addition, when, for example, the device 13A for developing in green must be the subject of a maintenance operation or supply of "toner", this device 13A is pulled outside along the guides 80 and 81 of the developing device (FIG. 32) without it being necessary to retract the toothed wheel 12 or the like, then it is removed from the main body of the imaging device. Thus, the mechanical arrangement of the main body X can be simplified.

 Furthermore, in this embodiment, the black developing device containing a one-component magnetic developer is disposed at a higher level, while a chromatic developing device 13A (13B, 13C) containing the non-magnetic "toner" with two components is arranged at a lower level. Consequently, a decrease in the density of the image can be avoided as a result of a darkening of the photosensitive element, and it is possible to prevent deterioration of the sleeve, erroneous operation and the appearance of vacuum in an image result from deterioration of the support.

 Figures 37 and 38 show a structure in which the mechanisms driving or containing the developing device, provided in the main unit X and in the magazine Y, are connected to each other by gear at their junction. Thanks to this structure, the drive motor can be common for the two devices. In addition, in this example, the development device can be moved correctly and synchronously.

To transport the developing device to the imaging station in the vicinity of the photosensitive drum 1 in the main body
X of the device, there are two means of transport (left and right). A DC motor M is fixed as a source of motive force to that of the means of transport of the store Y which is close to the motor M, and the rotation of the output shaft of this motor is transmitted to a transmission shaft 75 by means of toothed wheels 71 and 72. The rotation of the transmission shaft 75 is transmitted to shafts 74A and 74A by means of bevel gears 73 and 73, 74 and 74 arranged on the respective sides, and it is further transmitted to a toothed wheel 51 mounted on levers 51F via the toothed wheel located in the lower position of Figure 38.The lever 51F is mounted on the shaft 74A in order to rotate in a horizontal plane. A control rod for the coil 76 is mounted on one end of one of the levers 51F, while a spring SP is mounted on the other end. A link 77A is articulated, by a point adjacent to one of its ends, on the other lever 51F, and the other end of the link 77A is articulated on the magazine Y. The link 77A and the first city of the levers 51F are connected by a link 77.

 In the middle of the transmission shaft 75 are mounted left and right gear wheels 78 and 78. The rotation of the shaft 75 is transmitted to the gear wheels 52 and 52 which mesh with racks 521 and 521 formed on the two sides of the upper surface of the developing device 13A, by means of the toothed wheels 78 and 78 and the toothed wheels 79 and 79. On the two sides of each of the developing devices 13A, 13B and 13C, similar racks are formed to mesh with toothed wheels 51 and 51.

 Under the action of the coil 21, the toothed wheel 51 is brought into engagement with the rack 511 and the DC motor M is started, then the toothed wheels 51 and 52 located on the two sides are driven simultaneously. Thus, the developing device is transported to the image forming apparatus. When the front end of the developing device 13A reaches the toothed wheels 52 and 52, these mesh with the racks 521 and 521, whereby the transport of the developing device 13A is continued until this device 13A is placed in position in the imaging station.

 As described above, in this embodiment, a single source of motive force (the DC motor M) can be used to control several drive means for transporting the development device in synchronism.

 In the preceding description, the drive mechanism comprising the DC motor (source of motive force) is arranged in the magazine Y; but it can be arranged in the main body of the image forming apparatus, and the transport means can be divided between the mechanism located on the side of the magazine and a mechanism located on the side of the main body.

 Regarding the source of motive force, one can use a motor for this particular use, or another motor placed in the main body X, in which case the driving force is taken as desired by means of a transmission mechanism such as a clutch or the like.

 It goes without saying that many modifications can be made to the device described and shown without departing from the scope of the invention.

Claims (40)

 1. Apparatus for storing several development devices, characterized in that it comprises an enclosure (150) of a mobile store approximately vertically, comprising several shelves (151a151d) of partitioning arranged vertically to accommodate in a mobile manner the various devices for development (13A, 13B, 13C), and a motive force receiving member for fixedly supporting the partitioning shelves and for receiving motive force in a substantially vertical direction, a displacement mechanism for engaging with one , selected, development devices resting on the partitioning shelves for moving in a horizontal plane the development device chosen with respect to the partitioning shelf, and means for mounting the storage device (Y) on a image forming apparatus (X) with which said storage apparatus is used.  2. Apparatus according to claim 1, characterized in that it further comprises an enclosure (150) having an opening adjacent to its vertical center and having a space intended to store said development devices, this space having a vertical length greater than the sum of the thicknesses of the elements constituting the partitioning shelves and the heights of (2n-1) developing devices, where n is the number of developing devices that can be accommodated in the storage device, said enclosure being equipped with said means mounting.  3. Apparatus according to claim 2, characterized in that the movement mechanism can act on the developing device located on one of the partitioning shelves, only in a position corresponding to the opening.  4. Apparatus according to claim 3, characterized in that the movement mechanism is laterally distant from the enclosure of the store at least when this enclosure moves vertically, and is brought into its working position close to the enclosure of the store when the development device must be moved in order to engage with the development device.  5. Apparatus according to claim 1, characterized in that it further comprises means (C1, C2, C3) for detecting colors of the developers contained in the development devices.  6. Apparatus according to any one of claims 1 to 5, characterized in that it further comprises a source of motive force intended to produce a substantially vertical driving force and a substantially horizontal driving force, and means intended to reverse the force transmission between the vertical drive and the horizontal drive.  7. Apparatus according to claim 1, characterized in that it further comprises means (67) for feeding a sheet towards the image forming apparatus, said feeding means being arranged below the lowest of the partitioning shelves.  8. Apparatus according to claim 7, characterized in that it further comprises a collecting element (70) intended to collect the developer fallen from the developing device, this collecting element being disposed above the supply means and au- below the lowest of the partitioning shelves.  9. Apparatus according to claim 7, characterized in that it further comprises a source (493) of motive force intended to drive the supply means and the storage enclosure, and reversing means (D) intended to reverse the transmission of the driving force between the supply means and the enclosure.  10. Apparatus according to claim 2, characterized in that it further comprises means intended to assist the horizontal movement of the development devices from the partitioning shelves.  11. Apparatus according to claim 1, characterized in that it further comprises means intended to prevent a development device from arriving on a partitioning shelf when it carries another of said development devices.  12. Apparatus according to claim 1, characterized in that the movement mechanism comprises a force transmission element for each of the partitioning shelves.  13. Apparatus according to claim 1, characterized in that each of the development devices housed in the storage apparatus comprises racks (511) located on its respective lateral sides relative to the direction of movement of the development devices, the movement mechanism comprising toothed wheels (51) for transmitting force which can mesh with the created links.  14. Apparatus according to claim 13, characterized in that the racks are provided on the lateral vertical surfaces of each of the developing devices extending in the direction of movement of these devices, the toothed wheels being brought into engagement simultaneously with the rack respective lees and released simultaneously from these racks, and having the effect of transmitting substantially the same driving forces to said created meshes.  15. Apparatus according to claim 14, characterized in that a part of the lateral surface projects and in that the storage enclosure has a recess intended to guide the projection.  16. Apparatus according to claim 1, characterized in that it further comprises a guide (272, 282) of substantially concave shape, intended to guide a projection provided on each of the developing devices, one end of the guide close to the image forming apparatus being flared.  17. Apparatus according to claim 1, characterized in that the movement mechanism applies substantially the same transport forces to the lateral sides of the developing device with respect to the direction of movement of this device.  18. Apparatus according to claim 1, characterized in that it further comprises a control element intended to reduce the substantially vertical movement of a force transmission mechanism to drive the storage enclosure substantially vertically.  19. An image-forming apparatus, characterized in that it comprises an image-carrying element (11), means intended to form a latent image on this element, a transport passage (112) extending towards the image-bearing element for guiding a development device (13A-13C), a first movement mechanism intended to engage with the development device in the transport passage and to move it in a substantially horizontal plane, the image-bearing element, the means for forming a latent image, the transport passage and the first movement mechanism being arranged in a main body (100) of the image-forming apparatus (X), a device (Y), intended to store several development devices, which can be removably mounted on the main body, this storage device comprising a second movement mechanism intended to move the development device, located opposite the passage from tr ansport, to introduce it into this passage in a substantially horizontal plane, and a storage enclosure (150) comprising partitioning shelves (151a-151d) arranged approximately vertically to receive several development devices with which they can be moving, drive means being for selectively transmitting a drive force to the first drive mechanism, the second drive mechanism, and the storage enclosure.  20. Apparatus according to claim 19, characterized in that the drive means comprise an interface for transmitting a signal from the main body to the storage device and for transmitting a signal from the storage device to the main body.  21. Apparatus according to claim 19, characterized in that the main body comprises a shutter (55) intended to close and open the transport passage, ce. shutter being open when one of the developing devices moves between the transport passage and the storage device.  22. Apparatus according to claim 19, characterized in that it further comprises an intermediate element (24) intended to be inserted between the main body and the storage means to assist the transfer of the development devices between them.  23. Apparatus according to claim 19, characterized in that it further comprises a control element intended to limit the vertical movement of the storage device.  24. Apparatus according to claim 23, characterized in that the control element is in the form of a worm mechanism (114), of a stepped gear (C ') of a coil (116, 118) or a mechanical stop (119).  25. Apparatus according to claim 19, characterized in that it further comprises a collecting element (70) intended to collect the developer falling from the developing devices, this element being disposed in a lower position between the main body and the device 'storage.  26. Apparatus according to claim 25, characterized in that it further comprises means (67) for feeding a sheet towards the interior of the main body, the collecting element being disposed above said means d 'food.  27. Apparatus according to claim 19, characterized in that the main body comprises a development device guide located along the transport passage, the storage device comprising development device guides (80, 81) designed to be aligned with said guide of the main body, the parts of the respective guides close to each other having an inclined surface to form flared guides (271, 281).  28. Apparatus according to claim 19, characterized in that the transport passage and an outlet of the storage device are aligned by engagement between the main body and the storage device.  29. Apparatus according to claim 19, characterized in that the first drive mechanism comprises first and second transport means located on lateral sides of the developing device relative to the direction of movement of the developing devices so that substantially the same driving forces are applied alongside the development devices.  30. Apparatus according to claim 29, characterized in that the first drive mechanism comprises toothed wheels capable of meshing with an upper or lower surface of each of the developing devices, and in that the second drive mechanism comprises wheels gears (51) capable of meshing with racks (511) formed on the respective lateral vertical sides of each of the developing devices.  31. Apparatus according to claim 30, characterized in that it further comprises an additional developing device (14) located in the main body, which uses a one-component developer and which is arranged above the transport passage, the developing devices disposed in the storage device using a two-component developer, the toothed wheel of the first drive mechanism being capable of engaging a rack (521) formed on a bottom surface of each of the developing devices capable of being housed in the storage device.  32. Apparatus according to claim 19, characterized in that the drive means assume at least two force transmission functions from a single source of motive force.  33. Apparatus according to claim 32, characterized in that the drive means comprise reversing means (D) intended to produce a selective force transmission.  34. Apparatus according to claim 19, characterized in that it further comprises means (66) for manual feeding of a sheet into the main body, at least one of the drive mechanisms and means of the manual feed being driven by a common source of motive force, means (D) being provided for reversing the transmission of force from the motive force source.  35. Apparatus according to claim 19, characterized in that it further comprises pressure means (P) selectively disposed in the transport passage or outside this passage, in order to act on one of the development devices by applying pressure to it and releasing itself from the transport passage following a pressure relieving operation.  36. Apparatus according to claim 19, characterized in that the first drive mechanism comprises transport means intended to effect transport between the storage device and a waiting position in the main body, the training apparatus of images further comprising means (P) for pushing the developing device present in the waiting position towards the working position, the developing device and the transport means being engaged when they are in the position waiting, while the engagement is released when they are in the working position.  37. Development device which can be moved between a magazine (Y) with development devices and a main body (100) of an image forming apparatus (X), in a horizontal plane, characterized in that it comprises a container for containing a developer, a developer support member for removing the developer from the container to a development area in which the developer support member is opposed to, or in contact with, imaging means these means, and to bring the developer remaining in the container of the development device, an enclosure (150), the development device being movable in a certain direction when it is advanced from the magazine towards the interior of the training apparatus of images, a rack (511) being formed on each of the lateral sides of this device with respect to the direction of movement of said developing device, a rack (521) being formed on an upper or lower surface of the developing device.  38. Device according to claim 37, characterized in that it comprises a projection intended to be guided by a concave part (281) of the main body.  39. Device according to claim 38, characterized in that the projection in fact comprises several protruding parts arranged in several lines in the direction of movement.  40. Apparatus according to claim 19 or 30, characterized in that the image forming apparatus can be implemented in a manual sheet feeding mode, in which, when the storage enclosure is in a low position before the manual feed mode is chosen, the storage enclosure is moved up to allow manual feeding of the sheets after selecting the manual feed mode.