JPH0242466A - image forming device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a digital or analog method as a method of forming a latent image on an image carrier using light based on electrophotography, electrostatic recording, etc. The present invention relates to an image forming apparatus in which optical units employing these combinations can be easily replaced in one apparatus main body as necessary.

(Prior Art) Taking a copying machine as an example, the optical system and the vicinity of an image carrier inside a conventional image forming apparatus such as a copying machine or a printer such as a laser beam printer (LBP) are shown in FIG. It is constructed as follows: an original table glass 2 (either movable or fixed type is acceptable) for placing the original 1, a fluorescent lamp 3, and a fluorescent lamp 3 that illuminates the original 1 and illuminates the surface of the photoreceptor drum, which is an image carrier. 4. Reflective shade used for pre-exposure (however, pre-exposure is not necessary during contact charging).
It includes a short-range focusing lens group (hereinafter referred to as SLA) 5 for receiving reflected light from the original 1 and forming an image thereon, a photosensitive drum 6 on the surface of which this image formation is performed, and the like. Here, the surface of the photoreceptor drum 6 whose surface has been uniformly negatively charged by the charger 7 in advance (surface potential Vo at this time -700V)
, an electrostatic latent image is formed on the surface by the light that passes through 5LA5 while rotating in the direction of arrow a in the figure. and,
The toner image is developed by the developing device 8 to form a toner image on the surface of the photosensitive drum 6. Then, the toner image is transferred onto the transported paper by the transfer charger 9 and fixed by the fixing device 11. This conveyance is performed by registration rollers 12 and the like. At this time, the toner remaining on the surface of the photoreceptor drum 6 is cleaned by the cleaner 10, and the remaining potential on the drum is eliminated by the pre-exposure, completing one cycle.

By repeating the above steps, any number of copies of the original can be easily obtained.

(Problem to be Solved by the Invention) However, in the conventional example, since the image forming apparatus main body is provided with optical systems such as fluorescent lamps 3 and 5LA5, each function is A comprehensive check (adjustment, etc.) of each component was required. Furthermore, since the image carrier, developing device, etc. were designed to be used as an image forming device with only the functions of a copying machine, there are cases where it is designed to be used as a printer by modification, or when it is designed to be used as a printer with digital/analog compatibility. When developed into a device, it was not only difficult to standardize the optical system, but also required major modifications.

In addition, in general, only one function is preferentially added to one device, such as a copying machine, a printer (LBP, LED
, LSA, etc.).

Further, digital copying machines (such as LC) having multiple functions have a complicated structure and are expensive.

Therefore, the present invention has been made to solve the above-mentioned problems of the conventional example, and its purpose is to make it possible to deploy it to various devices at low cost, to make it possible to adjust it with a single optical unit, and to make the device An object of the present invention is to provide an image forming apparatus that does not require adjustment after being assembled into a main body.

(Means for Solving the Problems) The present invention provides an optical unit that illuminates a document and reflects light, or emits, reflects and transmits light in conjunction with an image information signal, and an optical unit that forms an image of the light on an image carrier. The image forming apparatus includes an apparatus main body for developing, developing, and transferring onto a transfer material, and the optical unit is configured to be detachable from the apparatus main body via a positioning means.

(Function) The part responsible for the process of forming an image with light on an image carrier, developing it, and transferring it to a transfer material is an analog copier, digital printer,
A common device can be provided for digital/analog copying machines, etc. Therefore, by making the optical unit removable, which illuminates the document and reflects the light (analog method), or emits, reflects, and transmits light along with the image information signal (digital method), the conventional Various functions such as an analog copying machine, a digital printer, and a digital/analog copying machine can be obtained, and costs can be reduced because only one device body is required.

In addition, since multiple optical units can be used and each unit can be checked, even if a failure or abnormality occurs and requires repair, all you need to do is check one of the multiple optical units. Moreover, since the main body of the apparatus is designed from the beginning to be used in common with a plurality of optical units, the conventional problem of difficulty in standardization is solved.

(Embodiment) An embodiment of the present invention is shown in FIGS. 1 and 2, and parts that are the same as those in the prior art will be described with the same reference numerals. Figures 1 and 2 are longitudinal cross-sectional views showing the state in which different optical units (22) U are attached to the same device body A.
In the figure, the casing of the optical unit U is indicated by thin diagonal lines.

Figure 1 shows an analog unit as an optical unit that illuminates the original and reflects light, especially a sheet-through analog unit that manually feeds the original. It is fed by sliding on the surface. This supply is carried out by two pairs of document transport rollers 21 provided before and after the document table glass 2.
22. A document 1 passing over a document table glass 2 is illuminated by a fluorescent lamp 3 . A reflective shade 4 is provided around the fluorescent lamp 3 to concentrate the light near the document table glass 2. The light reflected from the illuminated original is received by 5LA5, and an image is formed on the surface of photosensitive drum 6, which is an image carrier provided in translation main body A. Note that the shutter 23 is shown in the figure, and is in the position indicated by the dotted line in the figure when the device is in operation.

In addition, a charger 7, a developer 8, a transfer charger 9, a cleaner 1
0, the fixing device 11, and the registration rollers 12 are similar to those in the conventional example, so their explanations will be omitted.

Further, the optical unit U and the main body A of the apparatus are positioned so that the optical axis of the optical unit 5LA5 of the optical unit U is on a predetermined surface of the photosensitive drum 6. This positioning is performed by a convex portion 24 as a positioning means formed on the optical unit U side and a concave portion 25 provided on the device main body side that fits into this convex portion.

The illuminance on the surface of the photoreceptor drum 6 is automatically adjusted.

In other words, a dimmer for the fluorescent lamp 3 is provided on the optical unit side, and a sensor detects the reflected light using a mirror (not shown) on the main body of the device, and the sensor automatically detects the reflected light. The light is controlled by the dimmer. In addition, in other embodiments, if the main body of the device is provided with a dimming function, the light may be dimmed while performing serial communication between the main body of the device and the optical unit. Switching knob (not shown) that switches to the image forming conditions on the device main body side that are optimal for the optical unit.
is provided.

FIG. 2 shows an LBP digital unit as an optical unit (U) which emits a laser beam in response to an image information signal and forms an electrostatic latent image on the surface of a photosensitive drum on the side of the main body A of the apparatus.

This LBP digital unit mainly includes a laser scanner 31 that emits a laser beam that scans in the main scanning direction (in the width direction of the photoreceptor drum), and a reflecting mirror 32. The laser scanner 31 mainly includes an interface (I/F), a controller, an LD, a polygon lens, and the like.

Upon receiving the image information signal sent from the outside, the signal is sent to the laser scanner 31 via the I/F, and the laser beam is scanned onto the surface of the photoreceptor drum 6, and as the photoreceptor drum 6 itself rotates. , an electrostatic latent image is created. At this time, the optical axis of the laser beam is positioned at a predetermined position on the surface of the photosensitive drum by the same positioning as explained in FIG. 1 above. Further, a dimmer is provided on the optical unit side to automatically adjust the amount of light of the laser beam as described in FIG. 1 above.

In this embodiment, the laser scanner 31 scans by so-called back brand scanning. Thereby, there is no need to replace the photosensitive drum 6, the developing device 8, etc.

In other embodiments, it is also possible to perform so-called image scanning by switching the operating conditions of the charger 7, the developer 8, etc.

This switching may be performed by a frame on the optical unit side as explained with reference to FIG. 1. Note that the recording density of the LBP is assumed to be about 400 dpi.

Note that the L unit is different from the digital unit explained in Fig. 2.
An embodiment in which the ED array digital unit is an optical unit is also conceivable. This LED array unit includes an interface (I/F), a controller, an LED array,
It consists of 5LA (wide angle type), FL lashatter, etc.

In this optical unit, the amount of light from the LED must be increased in accordance with the characteristics of the photosensitive drum of the apparatus main body 9, and therefore the SLA is of a wide angle of view type. This embodiment allows high-speed image formation with a degree of resolution of about 240 dpi to 300 dpi.

Furthermore, it is also possible to create other embodiments by employing a liquid crystal shutter array digital unit as the digital unit as the optical unit. This liquid crystal shutter array digital unit is composed of an interface (I/F), a controller, a liquid crystal shutter array, a backlight, an SLA, and the like.

Further, it is also possible to adopt an embodiment in which an analog unit serving as an optical unit is different from that explained in FIG. 1 above. The analog unit of this embodiment is composed of a fluorescent lamp, a reflective shade, an original table glass, an SLA, and a filter (replaceable with other filters). By changing the transmission wavelength of the filter, it is possible to reproduce only a specific color, that is, to develop only the desired color. However, it is impossible to separate white and black and develop only one.

In the above embodiments, an analog unit or a digital unit was explained as the optical unit.
In addition, as other embodiments, it is possible to create a dedicated optical unit according to the purpose, such as an optical unit for both analog and digital use, and an optical unit dedicated to negative/positive projectors. It becomes possible to arrange a large number of optical units and use them for multiple purposes.

(Effects of the Invention) As explained above, according to the multifunctional image forming apparatus of the present invention, by arranging a plurality of optical units, one apparatus main body can be used for analog copying machines, digital printers, digital/analog copying machines, etc. You can get multiple functions at low cost.

In addition, it is no longer necessary to perform a total check (adjustment, etc.) for each component that has each function in the event of a failure or abnormality, as in the past, and only the optical unit that has one function needs to be checked. Since the main body is designed to be common for multiple functions, there is no need for major modifications to provide each function, unlike in the past.

[BRIEF DESCRIPTION OF THE DRAWINGS] FIG. 1 is a vertical sectional view of the entire device in which an analog unit is installed as an optical unit, and FIG. FIG. 3 is a vertical sectional view of the entire apparatus showing a state in which the optical unit shown in the figure has been replaced with a digital unit, and FIG. 3 is an explanatory diagram showing the main parts of the conventional image forming apparatus. Explanation of symbols 1...Original 2...Original table glass 3.
...Fluorescent lamp 4...Reflector shade 5...SLA
6...Drum 7...Charger 9...Transfer charger 11...Fixer 8...Developer 10...Cleaner 12...Register roller Fig. 1A...Device main body U...Optical Ninit-nl11. iii> Figure 2

Claims (1)

[Claims] an optical unit that illuminates a document and reflects light, or emits, reflects and transmits light in conjunction with an image information signal;
An image forming apparatus comprising: an apparatus main body for forming an image of the light on an image carrier, developing the image, and transferring the image to a transfer material; the optical unit is configured to be detachable from the apparatus main body via a positioning means. Device.