JPS62231269A - Life detection system for drum unit of image forming device - Google Patents

Abstract

PURPOSE:To decide the life of a unit by providing a means which measures and integrated the time required for a form to pass and a means which displays the integrated value. CONSTITUTION:A CPU 60 is provided with a program which receives an on signal from a detection switch 46 provided on the paper discharge side of a fixing device and calculates the time required for the form to pass through the detection switch 46, an integrating function program which integrates the calculated value, and a program which converts the integrated value to a stan dard form, and the converted value is displayed on the side of the CPU 60. When a print button is pressed, a print start signal is inputted to the side of the CPU 60 to start copying operation with the signal, and the detection switch 46 is turned on by the front end of the form and turned off when the rear end leaves the detection switch 46. The on signal and off signal are inputted to the side of the CPU 60, which determines the passing time of one form accord ing to the calculation program. Consequently, the replacement period of a drum unit is known without any mistake.

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.

Conventionally, image forming apparatuses are equipped with a developer storage case provided 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 being

In other words, in the cleaning process of electrophotographic systems 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 in this type of image forming device, when the waste toner tank reaches a predetermined level or higher, the life of the drum itself has come to an end. As a possible solution, the drum unit is replaced.

However, the deterioration in drum quality is more precisely proportional to the time the paper passes through the drum. In other words, in the above example, the life of the drum unit is determined by the amount of waste toner, but the amount of waste toner varies depending on the content of the print and the density of the print, so the waste toner itself is the same as the life of the drum unit. Not proportional.

Therefore, an object of the present invention is to provide a method for calculating the paper passage time and determining that the drum unit has reached the end of its life if it exceeds a specified value, in order to more accurately determine the life of the drum unit. The object of the present invention is to provide a lifespan detection method that can accurately determine the lifespan of a drum unit.

Another object of this invention is to accurately determine paper passing time.
That is, by calculating the time that the drum unit actually contributes to printing, displaying this result on a counter, and attaching the counter to the drum unit, it is possible to directly determine the lifespan of the drum unit.

1. For divination.

The present invention includes means for measuring the time during which the paper passes and integrating the measurement results, and means for displaying the integrated value.

1. To measure the time it takes the paper to pass, an on signal from the paper detection switch is input to the CPU side. The CPU integrates this and displays the result.

1 starBefore giving a detailed explanation of the present invention, 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 photosensitive laser optical unit C1 consisting of a laser oscillator 3, a rotating mirror 4, a reflecting mirror 5, etc., which receives a signal from an image forming device (not shown) and outputs an output according to the signal. A charging device 7, a developing device 8, a cleaning device 9, which are provided near the body 6 and the photoreceptor drum 6,
An image forming unit (D) consisting of a waste toner tank 10, etc., a copy paper path switching device 11. Roller pair 12.12, guide 1
An upper paper ejection unit I-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, there 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 is fed, and 45 is the timing switch 44.
This is a registration roller provided in front of the photoreceptor drum 6 for timing with the photoreceptor 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 supply 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 rotation axis.

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. The motor rotates based on this signal, and thereby 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 sponge roller 40 is provided on the cleaning device 9 side of 7 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 a time counter therein, and this CPU 60 receives an on signal from a detection switch 46 provided on the paper ejection side of the fixing device 18, and detects the paper by detecting the detection switch 4.
6, an integration function program that integrates the calculated values, and a conversion program that converts the integrated values 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.

■When a print button (not shown) is pressed, a print start signal is input to the CPU 60 side.

(2) Copying is started based on the print start signal, the paper passes through the fixing device 18, and the leading edge of the paper turns on the detection switch 46.

(2) When the trailing edge of the paper comes off the detection switch 46, the detection switch 46 is turned off. These ON and OFF signals are input to the CPU 60 side, and the CPU EO side determines the passing time of one sheet of paper based on the calculation program.

By repeating steps 1 and 2, the Cr'U 60 calculates the passing time for each sheet of paper, and the integration program integrates the time. When the integrated value exceeds a predetermined time, a conversion program operates to convert it to standard paper (for example, ^44 side).

(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.

Note 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 a general copying machine.

According to the present invention, the lifespan of an image forming apparatus is detected by calculating the paper passing time, that is, the time that the drum unit actually contributes to printing, which makes it possible to accurately determine the lifespan. It will be done. Specifically, the paper passing time is measured by calculating and integrating the ON signal of the detection switch on the CPU side, and displaying the result directly on the display means attached to the drum unit side. , you can definitely know when 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...CI'U, 70...Display means. Patent applicant: Sanda Kogyo Co., Ltd. Agent: Patent attorney: Takaharu Ohnishi Figure 3

Claims (2)

[Claims] (1) A method for detecting the lifespan of a drum unit in an image forming apparatus, comprising means for measuring the time during which paper passes 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.