JPS61106359A - Image forming device - Google Patents

Abstract

PURPOSE:To prevent such an event as the sheet rest being zero by furnishing an image forming device such as laser printer, copying machine etc. with a sensing means which senses that the residual amount of sheets in the cassette has reached the set value, and emits a signal. CONSTITUTION:This image forming device is equipped with a cassette 10 to accommodate sheets stacked, which are sent to the drum surface by a feed roller to receive transcription of a toner image on drum through the action of a transcription electric charge device. In a sheet rest sensing device 14, an arm 141A is installed as the side plates 142a, 142b of the base plate 142 in such a way as rotatable through arm shaft 141, and a transparent type photo- sensor 144 for warning the sheets going to finish and another transparent type photo-sensor 145 for sensing that the sheets have gone out are arranged in a position as mating with a light shelter 141B fixed on the arm shaft 141. At the bottom, each cassette 10 is provided with a hole 10A to serve as an escape for the arm 141A coming down.

Description

DETAILED DESCRIPTION OF THE INVENTION [Scope of Industrial Application] The present invention relates to image forming apparatuses such as laser printers and copying machines.

More specifically, the present invention relates to an image forming apparatus having a sheet material loading means such as a cassette, a deck, and a manual feed stand, and a feeding means for feeding the sheet material of the sheet material loading means.

[Conventional technology]

Conventionally, this type of device uses a reflective or transmissive photo sensor as a means to detect the remaining amount of sheet material, such as a transfer sheet, in a cassette or deck, and only detects whether there is a transfer sheet or not. It is normal that

[Problem that the invention seeks to solve]

However, in recent years, in addition to the image forming apparatus alone, peripheral devices useful for the user, such as an automatic document feeder (ADF) and a sorter, have begun to be provided, and the efficiency of printing operations has improved. When using such a device to perform a large amount of printing work, the user usually does not go near the device during the printing operation, and very often comes to pick it up when the printing operation is finished. At this time, if there are not enough transfer sheets in the cassette or deck at first, even if the user comes to pick it up, the device will stop printing when there are no more transfer sheets, causing great inconvenience to the user. There were times when I would call.

As another example, in recent years, a laser printer having the above-mentioned cassette or deck paper feeding device has been used as a facsimile receiving device.

Faxes are sent not only during the day, but also at night when no one is around. If the transfer sheet in the cassette or deck runs out at this time, reception will be impossible.

[Purpose of the invention]

The present invention has been made in view of the drawbacks of the above-mentioned conventional examples, and an object of the present invention is to provide an image forming apparatus that can prevent accidents caused by the sheet material running out midway.

[Means for solving problems]

In order to achieve the above object, an image forming apparatus according to the present invention includes a sheet stacking means for stacking sheet materials, and an image forming apparatus that feeds the sheet materials of the sheet stacking means using a feeding means. The present invention is characterized in that a detection means is provided that detects that the remaining amount of sheet material in the sheet stacking means has reached a set value and issues a signal.

〔Example〕

The present invention will be explained below based on the illustrated embodiments.

FIG. 1 shows a laser printer to which the present invention is applied.

A scanning optical system unit 1 including a scanner motor, a polygon mirror, a lens, a mirror, etc. is arranged in the upper part of the main body 1OO. A rotating cylindrical photoreceptor 3 is arranged in the middle, and around it are a charger 4, a developer 5. Transfer charger6.
A cleaning device 7 and the like are arranged. Image exposure according to information is performed from an optical system unit on the surface of the photoreceptor that is uniformly charged by the electric device 4, and an electrostatic latent image is formed.
Next, this latent image is visualized by the developing device 5. On the other hand, the transfer sheet P is fed from the cassette IO to the surface of the drum 3 by the paper feed roller 12 and the feed rollers 13A and 13B, and the toner image on the tram is transferred by the transfer charger 6. Thereafter, the transfer sheet is separated by a separating means (not shown)
The image is separated from the drum and sent to a fixing device 9 through a guide 8. The toner image on the sheet is fixed by the fixing device 9, and the sorted image is discharged to the outside of the main body. On the other hand, photosensitive tram 3
Is the toner that remains without being transferred on top cleaned? tz7
recovered by. Further, a paper remaining amount detection device 14 is arranged below the main body at a position corresponding to the cassette 10.

As shown in FIG. 2, the paper remaining amount detection device W114
277) Arm 1 on side plates 142a, , 142b
41A is rotatably attached via an arm shaft 141, and a transmission type photo sensor 14 for paperless notice is mounted at a position opposite to a light shielding plate 141B fixed on the arm shaft 141.
4 and a transmission type photosensor 145 for detecting the absence of paper. Also.

A hole 10A is provided at the bottom of the cassette 10 for escape when the arm 141A descends.

Next, the paper remaining amount detection operation will be described (Figs. 3(a) to 5(b)).

When there are enough transfer sheets P in the cassette IO (FIG. 3(a)), the arm 14LA is rotated to the right in the figure.
The light shielding plate 141B on the arm is sensor 1 for paperless notice.
44 without blocking the sense window 144A (Fig. 3(b)
)), the printing operation of the main device continues.

Therefore, sensor 144. ．． At 145, the light from the light emitting diodes D, D2 is transmitted to the transistor T1.

When T2 is reached, a loop current as shown in (2) flows and the light emitting elements L1 and L2 (LED) do not light up.

As the printing operation continues, the transfer sheet P gradually decreases, and the arm 14LA descends accordingly. When the remaining amount of the transfer sheet P reaches the set value (Fig. 4 (&)), the amount of the transfer sheet P gradually decreases. The light-shielding plate 141B blocks the entrance window 144A of the sensor 144 for paper-free notice (FIG. 4(b)), and outputs a signal (lights up the light-emitting element) to display the information. Then, if the user replenishes the transfer sheet in the cassette, again: IS3 (a),
(b) Return to the state shown in the figure. If you continue the blitting operation without replenishing transfer sheet P, arm 1 will
41A rotates to the lowest point and arm 141A moves to hole 10A.
5(a)), the light shielding plate 141B blocks the sense window 145A of the paper-out detection sensor 145 (
:ttJS diagram (b)), outputs a signal (lights up the light emitting element L2).1 light emitting element L l + L2 is a light emitting tie auto D1. The light from D2 is blocked and the transistor T1
It lights up when the 9th block 2 is turned off and a loop current as shown in (■) flows.

As explained above, in an image forming apparatus having a cassette or deck, a remaining paper amount warning device is arranged for the cassette or deck to detect the state in which some transfer sheet remains in the cassette or deck, and output a signal to display the information. As a result, the user is informed of the remaining amount of transfer sheets in the cassette or deck, and when printing a larger amount, the user is asked to replenish the transfer sheets, thereby preventing accidents such as those described in C@. or,
When used as a facsimile receiving device.

By displaying as described above, it is possible to prevent an accident in which the transfer sheet suddenly runs out during reception and reception becomes impossible. This is particularly effective when using the transfer sheet at night when there is no one nearby and it is not possible to replenish the transfer sheet.

The above is a description of the embodiment of the image forming apparatus according to the present invention, but it goes without saying that the present invention is not limited to this embodiment.

For example, in the above embodiments, a case where a cassette or a deck is used has been described, but it is not necessarily necessary to use a cassette or deck type.

It may also be of a type in which the sheet material is simply placed on a sheet loading table.

Furthermore, regarding the remaining amount notice, see FIG. 7(a).

As shown in (b), a sensor 243 may be provided to issue an earlier notice. Therefore, the user may replenish the sheet material when the light emitting element L3 lights up. Light emitting element L1. The sheet material may be replenished when the lamp lights up, or depending on the subsequent usage conditions (■), the timing at which the warning message is generated may be increased.

〔Effect of the invention〕

Since the image forming apparatus according to the present invention is as described above, it is effective in preventing accidents caused by the remaining amount of sheet material in the sheet material loading means becoming zero.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of an image forming apparatus to which the present invention is applied, FIG. 2 is a perspective view of a cassette unit and a remaining paper amount warning device, FIGS. 3(a), (b), and 4(a). . (b), Figures 5 (a) and (b) are diagrams showing the operation of the remaining paper amount warning device, Figure 6 is a circuit diagram, and Figures 7 (a) and (b).
is a diagram showing the operation of the remaining paper amount warning device of another embodiment:
JSg diagram is a circuit diagram of another embodiment. 10---One cassette, 12---One paper feed roller. 14---One paper remaining amount detection device, 141A-, -arm,
141B---One light shielding plate. 144.145.243---One transmission type food sensor, 144A, l45A, 243A---Sense window.

Claims (3)

[Claims] (1) In an image forming apparatus that has a sheet loading means for loading sheet materials and feeds the sheet materials of the sheet loading means using a feeding means, the remaining amount of the sheet materials of the sheet loading means is a set value. An image forming apparatus characterized in that it is provided with a detection means that detects that the threshold has been reached and issues a signal. (2) The image forming apparatus according to claim 1, wherein the detection means is means for detecting the thickness of the sheet material of the sheet stacking means. (3) The means for detecting the thickness of the sheet material includes a member that is in contact with the surface of the sheet material of the sheet stacking means and operates in accordance with the decrease in the sheet material, and a signal that corresponds to the amount of operation of the member. The image forming apparatus according to claim 2, which comprises a member.