JP4435238B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an image forming apparatus such as a copying machine or a facsimile.

  In an image forming apparatus such as a copying machine or a facsimile, a toner supply unit, a photosensitive drum unit, a developing unit, etc. are detachably provided inside the apparatus casing, and are pulled out of the apparatus casing or stored again. Further, in order to perform maintenance inside the apparatus housing, many have a front cover or a front door (referred to as a front cover in this specification) that can be opened and closed.

  In many of such image forming apparatuses, during operation, toner is supplied from a toner supply unit in the apparatus casing through a toner path in the photosensitive drum unit to the developing unit, and an image is formed on the photosensitive drum. However, when a service engineer performs maintenance on the photosensitive drum unit, the photosensitive drum unit and the developing unit are detached, and toner or the like existing between the units is spilled. The paper may be soiled.

  For example, as in the conventional image forming apparatus shown in FIGS. 1 and 2, the front cover 3 is opened to draw out the developing unit 2 built in the apparatus housing 1, and the developing unit 2 is pulled out (the drawing direction is indicated by an arrow in the figure). X)), the developing unit 2 hits against the reinforcing rib 4 formed on the front cover 3 and cannot be pulled out smoothly, and further, the toner or developer is discharged from the developing unit 2 by a shock hitting the reinforcing rib 4. As described above, the paper feed tray in the paper feed device 5 below the device housing 1, the transfer paper stored in the paper feed tray 5, etc., and various parts in the machine, and the device housing 1 may spill out of the gap between the front cover 3 and the outside of the machine.

  The present invention has been made in view of such conventional problems, and an image forming apparatus that can reliably prevent spillage of toner, etc., and dirt caused by this when a photosensitive drum unit, a developing unit, and the like are attached and detached. The purpose is to provide.

  Another object of the present invention is to provide an image forming apparatus in which a unit such as a photosensitive drum unit can be attached / detached smoothly, and there is no fear of hitting the unit and breaking it or spilling contents.

In order to achieve the above object, an image forming apparatus according to a first aspect of the present invention is an image forming apparatus provided with a front cover that can be opened and closed for attaching / detaching a unit to / from the inside of the apparatus casing or for maintenance inside the apparatus casing. ,
The distal end portion of the lower base of the apparatus housing for mounting on the SL unit, formed by providing a bag-like or groove-like concave portion for containing the toner spilling, etc. when detaching the unit by opening the front cover It is characterized by that.

An image forming apparatus according to claim 1, at the time of maintenance of the current image unit and a photosensitive drum unit, even if the toner or the like is spilled by desorbing these units, etc., be made to accumulate spilled toner in the concave portion can, toner can be prevented it due to contamination and child splashed into and outside of the apparatus system, reliably preventing the recording sheet in the sheet feed tray and the paper feed tray is often at the bottom of the device housing from dirt There is an effect that can be.

  The best mode for carrying out the present invention will be described below with reference to the embodiments shown in the drawings. In the following description, common parts are denoted by common reference numerals, and redundant description is omitted.

  FIG. 3 is a schematic perspective view of the first embodiment of the image forming apparatus according to the present invention, and FIGS. 4A and 4B are enlarged sectional views of the main part. The image forming apparatus according to the present embodiment includes a developing unit 2, a toner supply unit, a photosensitive drum unit, and the like inside the apparatus housing 1, and the front cover 3 is pivoted about a fulcrum 3a for attachment and detachment of each unit and maintenance. The inner surface of the front cover 3, that is, the upper surface when opened, is positioned further below the surface of the lower base 10 of the apparatus housing 1 in which each unit is housed. It is comprised so that it may do.

Therefore, in this embodiment, a bag-like or groove-like concave portion 11 is formed at the tip of the lower base 10 of the apparatus housing 1. As a result, when the service engineer opens the front cover 3 and performs maintenance on the developing unit 2 and the like, even if the developing unit 2 and the like are detached and the toner or the like is spilled, most of the spilled toner is the concave portion 11. A small amount of toner that enters and does not enter also remains on the upper surface of the lower base 10 or the upper surface of the front cover 3. Therefore, it is possible to surely prevent the toner from being soiled and to easily clean and remove the spilled toner.

  FIG. 6 shows a modification in which the spilled toner can be easily and reliably cleaned by forming the inner side edge and corner of the concave portion 11 in a curved shape.

Further, the image forming apparatus according to the present embodiment has the same height as the reinforcing rib 4 extending on the inner side surface of the front cover 3 in the direction orthogonal to the unit drawing direction (arrow X in the figure) of the developing unit 2 and the unit drawing direction. Guide ribs 4a oriented in the same direction as X are formed. With this guide rib 4a, the developing unit 2 and the like can be pulled out and inserted smoothly, and toner spillage due to shock or the like can be avoided.

Further, in the image forming apparatus of the present embodiment, in addition to the guide rib 4a of the third embodiment, the pair of lateral misalignment prevention ribs 4b are arranged at positions corresponding to the left and right width w of the developing unit 2 with a slight interval W. Is provided to be wider than the right and left width w of the developing unit 2 and is used as a guide for drawing out and inserting the developing unit 2 so that the developing unit 2 can be inserted and removed almost straight. Is missing.

It is a perspective view which shows the state which opened the front cover of the conventional image forming apparatus. It is a perspective view which shows the drawer state of the developing unit. 1 is a schematic perspective view of a first embodiment of an image forming apparatus according to the present invention. It is an expanded sectional view which shows the site | part used as the implementation object of this invention . 1 is an enlarged cross-sectional view of a main part of a first embodiment of an image forming apparatus according to the present invention. It is an enlarged sectional view of a modification of the embodiment shown in FIG. It is a principal part perspective view of another modification . It is a principal part perspective view of another modification .

Explanation of symbols

1: Device housing 2: Development unit 3: Front cover 4: Reinforcement rib 4a: Guide rib 4b: Horizontal displacement prevention rib 5: Paper feeding device 10: Lower base 11: Concave portion w: Horizontal width of development unit W: Horizontal displacement Interval between prevention ribs X: Pull-out direction of development unit

Claims (1)

In an image forming apparatus provided with a front cover that can be opened and closed for detaching a unit inside the apparatus housing and maintenance inside the apparatus housing ,
The distal end portion of the lower base of the apparatus housing for mounting on the SL unit, formed by providing a bag-like or groove-like concave portion for containing the toner spilling, etc. when detaching the unit by opening the front cover An image forming apparatus.