JPS62231271A - Life detection system for drum unit of image forming device - Google Patents

Abstract

PURPOSE:To decide the life of a drum unit directly by providing a means which measured the operation time of the blade of a cleaning device and integrates the measurement result and a means which displays the integrated value. CONSTITUTION:A CPU 60 has a program which calculates the time from the reception of a blade-on signal to its turn-off state, a program which integrated the calculated value, and a program which converts the integrated value to a standard form, and the converted value is displayed on a display means 70. When a print key is pressed, the on signal for the solenoid of the blade of the cleaning device is inputted to the CPU 60, which determines a clutch-on time per form by the calculation program on the basis of the signal. Then, a blade-on time per form is calculated and integrated by the integration program and if the integral value exceeds a specific time, the conversion program operates to display the integrated time in terms of the number of standard forms. When the displayed value reaches a specific quantity, it is decided that the life of the drum unit reaches its expiration.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for detecting the life of a drum unit in an image forming apparatus.

Generally, in an image forming apparatus, there is a developer storage case installed near the photoreceptor, and a waste toner tank that collects toner remaining on the surface of the photoreceptor by scraping it off with a blade in a cleaning device. It is provided.

In other words, in the cleaning process of electrophotographic methods such as copying machines, toner is removed from the photoreceptor (hereinafter referred to as the drum) and collected in a waste toner tank, and normally the drum, cleaning blade, and waste toner tank are In many types of image forming devices, a drum unit configured as a single system is built into a general copying machine, and when the waste toner tank reaches a predetermined level, the life of the drum itself has come to an end. As a possible solution, the drum unit is replaced.

n<y! However, the deterioration of the quality of the drum is more precisely proportional to the operating time of the blade in the cleaning device. In other words, in the above example, the lifespan of the drum unit is determined by the amount of waste toner, but since the amount of waste toner varies depending on the content printed and the density of the print, the waste toner itself is a factor in determining the lifespan of the drum unit. It's not proportional as it is.

Therefore, an object of the present invention is to provide a determination method that calculates the blade operating time of a cleaning device and determines that the drum unit has reached the end of its life if the blade operating time of the cleaning device exceeds a predetermined value, in order to more accurately determine the life of the drum unit. The purpose of the present invention is to provide a lifespan detection method that can accurately determine the lifespan of a drum unit.

Another object of the present invention is to accurately calculate the operating time of the blade, that is, the time that the drum unit actually contributes to printing, display this result on a counter, and attach the counter to the drum unit. , it is possible to directly determine the lifespan of a drum unit.

, I 2 This invention comprises means for measuring the operating time of the blade of the cleaning device and integrating the measurement results, and means for displaying the integrated value.

1. When the print key is pressed, the blade of the cleaning device is activated. This operating time is input to the CPU side as a blade clutch ON signal. The CPU integrates this and displays the result.

Before explaining the present invention in detail, an outline of an image forming apparatus will be explained using a laser printer as an example.

FIG. 1 is a sectional view of an image forming apparatus (laser printer) according to the present invention, and FIG. 2 is a sectional view showing essential parts of the image forming apparatus.

This laser printer consists of an upper unit A and a lower unit B that can be rotated in the direction of arrow P about a support shaft 2, and is configured in a so-called Taramsiel type.

Inside the upper unit A, there is a laser optical unit C1 photoreceptor, which includes a laser oscillator 3, a rotating mirror 4, a reflecting mirror 5, etc., which receives a signal from an image forming apparatus (not shown) and outputs an output according to the signal. 6 and a charging device 7, a developing device 8, a cleaning device 9, and a charging device 7 provided near the photoreceptor drum 6.
Image forming unit D consisting of waste toner tank 10 etc., copy paper path switching device 11, roller pair 12, 12, guide 1
An upper paper ejection unit E made of 3.13 or the like is provided. Note that the drum unit is one in which the photosensitive drum 6 and the waste toner tank 10 are integrally constructed.

14 is an upper paper discharge section. Inside the lower unit B is a paper feed unit consisting of a paper feed cassette 15, a paper feed roller 16, a timing switch 44, a registration roller 45, etc.
F. A transfer device 17 and a fixing device 18 are provided near the photoreceptor 6. Reference numeral 19 indicates a paper discharge tray that is provided to be freely unfoldable and foldable in the direction of arrow Q, and reference numeral 20 indicates a manual feed unit that can rotate in the direction of arrow R about the support shaft 2. Note that 44 is a timing switch for detecting that paper has been fed, and 45 is a registration roller provided in front of the timing switch 44 for timing with the photosensitive drum 6.

The developing device 8 is configured as follows.

That is, 22 is a developer storage case for storing a developer 23 made of toner and carrier, and an opening 24 is formed corresponding to the photoreceptor 6, and a non-magnetic developing sleeve 25 is formed in the opening 24. are horizontally arranged around an axis parallel to the rotation axis of the photoreceptor 6. A magnet 26 is disposed within the developing sleeve 25 in a stationary state.

Reference numeral 27 denotes a toner replenishment case that is connected to the developer storage case 22 through an opening 28 above the developer storage case 22, and a toner replenishment roller 29 is provided above the opening 28 (on the side of the toner replenishment case 27). ing. The toner replenishing roller 29 is made of, for example, a sponge having a large number of recesses on its outer peripheral surface, and is configured to be rotated at a predetermined speed by a motor (not shown).

As the toner replenishing roller 29 rotates, the toner 31 present in the recess is squeezed out by the edge of the opening 28, and a predetermined amount of toner 31 is supplied to the developer storage case 22. Reference numeral 32 denotes an agitation supply tool that agitates the developer 23 and the toner 31 supplied through the opening 28 and supplies it to the developing sleeve 25, and is rotatable around an axis parallel to the rotation axis of the developing sleeve 25. It is installed horizontally.

Reference numeral 33 denotes a cutting plate that relatively cuts off excess developer 23 on the developing sleeve 25 as the developing sleeve 25 rotates. 34 is a partition plate, and the developer 23 after the ear cutting is
It is configured to flow down and return onto the stirring supply tool 32 while being biased toward one end of the stirring supply tool 32. 35
is a spiral body for transporting the developer that introduces the biased and reduced developer 23 into one end of the agitation and supply tool 32 and leads it out to the other end of the agitation and supply tool 32; It is installed horizontally so that it can freely rotate around an axis parallel to the . Reference numeral 36 denotes a toner concentration detection sensor provided in a case portion near the spike plate 33, which detects a decrease in toner concentration within the developer storage case 22 and outputs a predetermined signal. Based on this signal, a motor (not shown) rotates, whereby a predetermined amount of toner 31 is supplied to the developer storage case 22 through the opening 28 . Further, the waste toner tank 10 is connected to the cleaning device 9 via an opening 37.
A blade 38 is provided on the cleaning device 9 side of 7, which is activated by turning on a blade clutch (not shown). A sponge roller 40 is provided to rotate around the rotation axis of the photoreceptor 6 for discharging the waste toner 39 scraped off by the blade 38 to the waste toner tank 10 side.

FIG. 3 shows a block diagram of one embodiment of the present invention.

Reference numeral 60 denotes a CPU having an internal time counter, and this CPU 60 runs a calculation program that calculates the time from when the blade-on signal is received until the signal turns off, an integration program that integrates the calculated value, and It has a conversion program that converts the value into standard paper.

Reference numeral 70 denotes a display means for externally displaying the converted value, and this display means is, for example, a segment type electronic display or a mechanical type counter, and is composed of a photosensitive drum 6 and a waste toner tank 10. This includes cases where it is installed directly on the drum unit, or cases where it is installed together with the drum unit and the panel of the aircraft body.

Here, it is assumed that a new drum unit has been replaced, and in this case, the display means of the drum unit has been reset to the initial value.

The operation of lifespan detection will be explained with reference to FIG.

(2) When a print key (not shown) is pressed, a signal is input to the CPU 60 to turn on a solenoid (not shown) for the clutch of the blade of the cleaning device.

(2) After the copying is completed, the blade solenoid OFF signal is input to the CPU EO.

(2) The CPU 60 uses the calculation program to determine the clutch-on time per sheet based on the blade solenoid-on signal.

(2) The CPU 60 calculates the blade on time for each sheet of paper, and the integration program integrates this. When the integrated value exceeds a predetermined time, a conversion program operates to convert it to standard paper (for example, A4 paper).

(2) The converted value is displayed by the display means.

(2) When the displayed value reaches a predetermined number of sheets, it is determined that the drum unit has reached the end of its life.

It should be noted that although the above description has exemplified a laser printer as an image forming apparatus, the present invention is not limited thereto, and can also be applied to general copying machines.

According to the present invention, the lifespan of the image forming apparatus is detected by calculating the operating time of the blade of the cleaning device, that is, the time that the drum unit contributes to printing, so it is difficult to accurately determine the lifespan. Since the drum unit is configured to measure, calculate, integrate, and display the results directly on the display means attached to the drum unit, it is possible to know without a doubt when it is time to replace the drum unit.

[Brief explanation of drawings]

FIG. 1 is a sectional view of an image forming apparatus (laser printer) according to the present invention, FIG. 2 is a sectional view showing the main parts of the image forming apparatus, and FIG. 3 is a block diagram of an embodiment of the invention. show. 60...CPU, 70...Display means.

Claims (2)

[Claims] (1) A method for detecting the lifespan of a drum unit in an image forming apparatus, comprising means for measuring the operating time of a blade of a cleaning device and integrating the measurement results, and means for displaying the integrated value. (2) A method for detecting the lifespan of a drum unit in an image forming apparatus according to claim 1, wherein the display means is provided directly on the drum unit.