JPS6087354A - Image recording device - Google Patents

Abstract

PURPOSE:To grasp the replacement period of a unit properly by detecting variation of a developer from its rated value in a developing device and a cleaning device. CONSTITUTION:The image process unit consisting of an electrostatic image carrier 1, developing device 2, and cleaning device 3 in one body is fitted detachably. Then, the device 2 is provided with a detecting means V1 which detects the developer decreasing in amount below a specific value. Therefore, the replacement period of the unit is known accurately and the small-sized, easy-to- service device is realized.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an image recording apparatus such as an electrostatic copying machine, and more particularly to an image recording apparatus having a replaceable image processing unit.

[Prior art]

In an image recording device that uses electrostatic images, an electrostatic image is formed on an electrostatic image carrier, toner is applied to the electrostatic image by a developing device to make it visible, and the resulting image is transferred to recording paper. , and fix it to obtain the desired recorded matter. After the image transfer is completed, the electrostatic image carrier is removed. ! ! After the residual charge is erased by stopping the electrodes, the toner remaining on the surface is removed by a cleaning device and the toner is reused.

The structure of the image recording device is functionally comprised of the above-mentioned image forming section, that is, the so-called image processing section, an optical system that scans the original and forms an image on the electrostatic image carrier, and a recording section from the abrasive feeding section to the paper ejecting section. The image forming unit is the most complex in terms of structure and function, and it is comprised of components with a limited service life, such as electrostatic image carriers, or components with a limited service life, such as toner. In order to simplify the maintenance of the image forming section, JP-A No. 58-21262 describes the use of electrostatic image carriers, charging electrodes, and developing parts. vessel.

An image recording apparatus has been disclosed in which an image forming means of a cleaning device is assembled into an integrated unit and detachably attached to a recording apparatus main body. When using such an apparatus, an image processing unit (hereinafter simply referred to as the unit) containing an amount of toner approximately corresponding to the service life of the electrostatic image carrier used is manufactured, and the unit is removed as necessary.
If the unit is replaced with a new one, frequent operations such as toner replenishment, electrostatic image bearing member replacement, and #5 adjustment are no longer necessary, making maintenance extremely easy.

When replacing the unit, count the number of recorded sheets, check the lifespan of the electrostatic image carrier, and check the toner loaded in the unit! Normally, this is done when a preset number of sheets has been reached, taking into account the actual toner consumption), or when the toner remains on the electrostatic image carrier during transfer and is collected in the cleaning device. The amount of toner is not necessarily constant depending on the density area of the original image or the conditions during development and transfer, and the toner may be consumed before the specified number of sheets are recorded, or conversely even though there is surplus toner. In some cases, the specified number of sheets is reached and usage is discontinued. In some cases, the amount of toner collected in the cleaning device may increase and overflow from the cleaning device, causing problems such as staining the copies.

In order to solve these problems, it is possible to have sufficient margin in the amount of toner loaded and the capacity of the cleaning device, but this can cause disadvantages such as the developing device and cleaning device becoming overcrowded, and toner waste increasing. There are many points.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide an image recording apparatus that is small and easy to maintain, and allows the user to accurately know when to replace a unit.

[Structure of the invention]

The above purpose is to keep the main body of the recording device busy, at least the electrostatic image carrier,
An image recording apparatus in which an image envelope forming process unit integrally configured with a developing device and a cleaning device is detachably attached is provided with a detection means for detecting that a pressure of a certain amount or more of agent has been reached. The method of detecting the amount of toner in the developing device and replenishing the toner by various methods is already known, but the present invention provides a completely closed system for the donor. A toner detection means is installed in both the developing device and the cleaning device, which is built into the replaceable unit. By generating a signal when the collected collected toner exceeds a certain amount and replacing the unit when any of the signals is generated, the process unit can be maintained until the toner is exhausted or the toner is about to overflow from the cleaning device. The aim is to use the most economical unit that uses up its capacity.

The development method used in the present invention is preferably a so-called -component development f& method using a magnetic toner.

As a means for detecting the presence of toner, for example, a method of detecting the amount of toner in a container using a microswitch or the like;
A known toner detection method can be used, such as an electrical detection method using the electrical resistance of the toner;
Particularly preferred is the method using a vibrating member disclosed in Japanese Patent No. 36874.

The method of detecting toner using the vibrating member is to detect the toner based on the effective displacement amount X when the vibrating part resonates.

A mechanically vibrating substance, for example, as shown in Figure 1, lies on a smooth surface with mechanical resistance r, and its center of gravity G is connected to a fixed point through a spring with a constant S, and an external force F is applied to the center of gravity G.
is applied, the side body with vibrating mass m becomes lot
Q t X K has been analyzed as is well known.

FIG. 2 shows an electrical circuit equivalent to that in FIG. 1. In the figure, C' indicates the capacitance between the electrodes.

Incidentally, the toner in contact with the vibrating member not only increases the mass of the assisting body as an additional substance, but also increases mechanical resistance to vibration as viscous resistance of the toner and sound radiation resistance. If the increase in mass is Δm9 and the increase in mechanical resistance is △r, then Q=□ r+Δr can.

The above-mentioned vibrating members include a plate that vibrates by receiving an instantaneous external force, a plate that vibrates by receiving an electrostatic or magnetic external force periodically or instantaneously, and a plate that vibrates by exciting vibration by itself. A magnetostrictive oscillator or the like can be used for the strain oscillation. When the toner oscillates due to an instantaneous force rather than a periodic external force, the amount of toner f can also be detected by detecting the decay time of the vibration.

As mentioned above, the toner detection using the vibrating member detects the toner adhering to the vibrating part, and this is installed near the lower end of the side wall of the developing device and near the upper limit of the collected toner storage section on the wall of the cleaning device, so that the toner is not consumed. It is possible to detect when the toner-accumulating surface is separated from the vibrating member attached to the developing device, and when the toner-accumulating surface reaches the vibrating member attached to the cleaning device to indicate that the toner-accumulating surface is full. Based on this detection result, an indicator lamp or a warning buzzer may be activated to notify that the toner is exhausted or the cleaning device is full, respectively, to notify that the process kit needs to be replaced.

The present invention will be explained below with reference to Examples.

〔Example〕

Fig. 3 shows an example of an electronic copying machine as an image recording device according to the present invention.

In the figure, 1 is an electrostatic image bearing member, a photosensitive drum 12 is a developing device, and 3 is a cleaning device, and together with some other members, these three constitute an integrated unit surrounded by a dashed line U in the figure. It is removably attached to the main body of the copying apparatus by known means. A certain amount of toner 4 is sealed in advance in the developing device 2 constituting the unit, and an electrostrictive vibrator Vl is attached to the lower side wall of the developing device 2 as a vibrating member for a toner detector. Further, an electrostrictive vibrator V for the same purpose is attached to the upper part of the side wall of the cleaning device 3. The toner is attached to the electrostatic image on the photosensitive drum 1 by the developing device 2, and transferred by the transfer electrode 5 onto the transfer material fed from the conveyance roller 6, but the remaining toner is scraped by the cleaning blade 7. It is collected and stored in the cleaning device.

The electrostrictive vibrator Vs s Vt has electrodes attached to both sides of a thin circular ceramic plate, and the - side is divided into two electrodes as shown in Fig. 4, each connected to a lead wire 41.
, 42 are exposed, and the entire surface of the other side is one electrode.
A lead wire 43 is coming out. Regarding the mass per unit area of the electrostrictive vibrator and the mounting method, the following considerations are taken to improve detection efficiency. In other words, it is possible to reduce the mass per unit area, to improve the adhesion of toner to the electrostrictive vibrator, or to prevent adhesive from forming on the vibrator surface when attaching the electrostrictive vibrator to the wall surface of the developing device or cleaning device. Care must be taken to avoid increasing the mechanical resistance Δr by adding an unnecessarily large number of them on the top. Lead wires from each electrostrictive vibrator are connected to an electric circuit shown in FIG. 5 to constitute a toner detector.

The circuit is an oscillation circuit A,'f that vibrates the electrostrictive vibrator V.
! It consists of a detection circuit B that detects whether the L strain oscillator V is oscillating or not, and a circuit C that converts the output of the detection circuit B to direct current.

When the electrostrictive vibrator V is not in contact with toner, it exhibits the frequency-admittance characteristic shown in FIG. Using this difference in admittance,
In this embodiment, the electrostrictive vibrator V vibrates when the toner is in contact with the electrostrictive vibrator V, and does not vibrate when the toner is in contact with the electrostrictive vibrator VC (that is, so that Q is 0). The constants of the electrodes of V, the resistance of the oscillation circuit A, the transistors, etc. are determined.

When the vibrator V is vibrating, an AC voltage waveform as shown in the figure Tb) is shown, and the vibration is detected. The integrating circuit C receives this output, and the electrostrictive vibrator outputs a signal voltage when the vibrator is vibrating, and stops the signal when the vibrator comes into contact with toner and stops the vibrator.

When the copying machine shown in Fig. 1 is operated continuously and the toner in the developing device N2 gradually decreases until the surface of its accumulation reaches the lowest position Dyn1n and moves away from the electrostrictive vibrator v8, the vibrator starts to vibrate and a signal is output from the detection circuit. Output (ON).

Further, the collected toner in the cleaning device 3 increases and the surface of the accumulated toner reaches the overflow limit Rwax, and the electrostrictive vibrator V,
When it comes into contact with , the vibration stops and the signal from the detection circuit also stops (turns OFF).

As shown in the eighth prisoner, the output of each detection circuit is processed by CPU K, and the detection circuit 81 of the vibrator Vl attached to the developing device 2
When the signal output is turned ON, the indicator light 82 provided on the control panel 80 to indicate "no developer remaining" lights up, and the detection circuit section of the vibrator 6 attached to the cleaning device lights up. The configuration is such that when the signal output is turned on, the indicator light 8 indicating "collected toner full" lights up. It is preferable to use a light emitting diode or the like as the indicator light. It is also possible to sound a 9-notice buzzer or automatically stop the copying operation of the main body of the copying machine at the same time as the light is turned on.

If any of the above displays appears, copying can be resumed immediately by removing the process unit in use and replacing it with a new one.

〔Effect of the invention〕

In the image recording apparatus according to the present invention, although a closed type process unit is used, it is clearly indicated that the process unit must be replaced due to consumption of internal developer or the recovered toner is full, and defective copies due to lack of developer can be produced. It is possible to prevent troubles such as the occurrence of dust, staining of copies due to overflow of toner, or waste of materials due to premature replacement of the process unit.

Another advantage is that it is possible to detect malfunctions in the main body of the recording apparatus from an abnormal increase in the amount of A-recovered toner.

Although all the explanations regarding the structure of the invention have been made with reference to the embodiments of electronic copying machines, the application of the invention is not limited to this, and can be applied to various recording devices that utilize electrostatic images, such as data printers and facsimiles. Needless to say, it is widespread.

[Brief explanation of drawings]

Figure 1 (9m2) is a diagram showing the mechanical vibration system and electrical vibration system of the vibrating member, Figure 3 is a schematic structural diagram of the copying machine according to the present invention, Figure 4 is the structure of the vibrator) Figure 5 is Vibration detection circuit, Figure 6 shows vibration frequency-admittance characteristics, Figure 7
The figure shows the output waveforms, and the eighth row in the first row is a diagram of the main part of the embodiment. U...Process unit 2...Developing device 3...Cleaning device 81, 83...Vibration detection circuit 82, 84
... Indicator light V1 + shield ... Vibration member agent Yoshimi Kuwahara No. 4 Port No. 5 Figure 6 bY diagram

Claims (4)

[Claims] (1) In an image recording device in which an image forming process unit integrally configured with at least an image forming photoreceptor, a developing device, and a cleaning device is removably attached to the main body of the image recording device, the developing device is attached to the main body of the image recording device. An image recording apparatus comprising: a detection means for detecting that the amount of developer has fallen below a certain amount; and a detection means for detecting that the amount of developer has reached the certain amount or more in the cleaning device. (2) The image recording apparatus according to claim 1, further comprising display means for displaying the life span of the process unit based on the signals from each detection means. (3) The image recording apparatus according to claims 1 and 2, characterized in that the display means is configured so that the display based on the signal from each detection means is performed independently. (4) The image recording apparatus according to Claims 1, 2, and 3, wherein the earliest display among the independently displayed displays is the life span of the process unit.