1. Technical Field
The present invention relates to an indicator and an image forming apparatus, and more specifically relates to a mechanism to indicate where a paper jam occurs in the apparatus, and apparatus incorporating the indicator.
2. Related Art
In an image forming apparatus employing an electrophotographic method, a toner image is transferred to a sheet of recording media to obtain a printed document or a copy. The recording sheet is conveyed from a sheet feed device disposed inside the image forming apparatus to a transfer position, and to a fixing device after the transfer, after which the printed sheet is discharged.
The recording sheet is conveyed along a conveyance path, and therefore is subject to occasional defective conveyance such as a paper jam. Defective conveyance of the recording sheet is recognized by a sensor disposed in the conveyance path or by measuring the time required for the conveyance. If defective conveyance occurs, a message to that effect is displayed, prompting an operator to remove the jammed sheet from the apparatus.
When fixing a paper jam, it is useful to know the exact location of the jam. JP-H11-119609-A discloses a structure that indicates where the jammed recording sheet is located and how to take it out, and includes a liquid crystal display on a part of the control panel disposed on the exterior of the apparatus and another display on a part of the housing which is exposed when an openably closable door is opened.
In the structure disclosed above, the door is opened and the display is observed to find the defective conveyance. Without observing the display, there is no finding the paper jam quickly. Accordingly, because the jam cannot be located promptly, a long time can be taken to handle the problem. For example, if multiple covers are provided for covering different parts of the recording sheet conveyance path, it may not be clear which of the exterior panels should be opened.
To solve such a problem, it is conceivable that a display is provided on the exterior panel indicating which of the covers is to be opened. However, such an arrangement requires the addition of a power source to the display. Such modification in turn necessitates, for example, improving the mechanical rigidity of the exterior panel when disposing a drawer connector between the panel and the apparatus frame, thereby enlarging and complicating the panel structure, both of which are undesirable.