JPS63160953A - Image forming device - Google Patents

Abstract

PURPOSE:To accurately detect the remaining sheet numbers inside a paper cassette where it is difficult to check up from the outside, by installing a device which writes information according to service page numbers, on an outer surface of the paper feed cassette, reading this information, and judging the remaining sheets numbers. CONSTITUTION:A paper feed cassette 1 doubling as a storage case has a paper feed roller opening 6, a push roller opening 7 and a paper feed slit 9 in its body 3, and in the side 11, there is provided with a blank part where a bar code 12 showing various kinds of information on the paper 5 housed as much as the specified number of sheets inside and a black strip 13 showing service sheet numbers in succession to an initial setting black strip 13a are written. And, when the paper feed cassette 1 that a certain degree of sheet numbers are already consumed and the corresponding length black strip 13 has been written is attached to a device body 2, a reading device 22 reads information on size or the like of the paper 5 from the black strip 13, and another reading device 23 reads the remaining sheet numbers from the black strip 13, and at each paper feeding, a writing device 30 interpolates to the black strip 13 by means of heat transfer or the like, whereby the length is set down to the length conformed to an amount of use.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an image forming apparatus such as a copying machine that feeds paper into the main body of the apparatus using a paper feed cassette.

(Prior Art) In an image forming apparatus such as a copying machine, a means for detecting stack thickness has conventionally been adopted as a means for detecting the number of remaining sheets of paper in a paper feed cassette.

(Problem to be solved by the invention) However, according to the conventional paper remaining amount detection method, since the paper thickness is not constant depending on the type of paper, the stacked thickness does not necessarily indicate the accurate number of remaining paper sheets, and it lacks accuracy. There is a problem. Furthermore, since a plurality of sensors or a pulse disk is used as the detection means, there are problems in that the structure is complicated and costly, and it is not suitable for miniaturization.

(Means for Solving the Problems) The present invention solves the above problems by focusing on the fact that a paper feed cassette that also serves as a storage case contains a set number of sheets of paper. .

That is, the image forming apparatus of the present invention includes a paper feeding power center which has a fixed number of initially accommodated paper sheets and also serves as a storage case, means for writing information corresponding to the number of used paper sheets on the outer surface of the paper feeding cassette, and The present invention is characterized by comprising means for reading information, and means for determining the number of remaining sheets of paper in the paper feed cassette based on the read information.

(Function) According to the present invention, information corresponding to the number of sheets of paper used can be written by the writing means on the outer surface of the paper feed center which also serves as a storage case. Since the paper feed cassette has a fixed initial number of sheets of paper to accommodate, the information serves as an index indicating the number of remaining sheets of paper.

Therefore, the number of remaining sheets of paper in the paper feed cassette can be known from the information by the reading means and the judgment means,
Based on this, the number of remaining sheets of paper can be displayed, making it convenient to use.

In addition, since the above information is written on the outer surface of the paper feed cassette according to the number of paper sheets used, it is more suitable for showing accurate numbers than the conventional method of detecting the number of remaining paper sheets based on the thickness of the paper stack in the cassette. Moreover, the means for reading the information can be formed simply and compactly, which is advantageous in terms of cost and compactness.

(Embodiment) In the embodiment shown in the drawings, the present invention is applied to a copying machine.

This copying machine consists of a paper feed cassette 1 that also serves as a storage case and a device main body 2.
is removably inserted into the

1 to 3 show the paper feed cassette 1. As shown in FIG. FIG. 3 shows the paper feed cassette 1 before use, and the inside of the cassette main body 3 is protected in a moisture-proof manner by a storage M4. A predetermined number of papers 5 are contained in the cassette body 3,
Further, a paper feed roller opening 6 is provided at the front of the upper surface of the cassette body 3, and a push-up roller opening lower portion is provided at the front of the lower surface of the cassette body 3. A push-up plate 8 is disposed above the push-up roller phase opening lower. Further, a paper feed slit 9 is provided at the upper end of the front surface of the cassette main body 3, and the paper 5 is fed one by one from this.

The cassette main body 3 is formed in the shape of a closed box, and has a structure that prevents the user from replenishing additional paper 5. Further, the storage M4 seals both the openings 6.7 and the paper feed slit 9, so that the inside of the paper feed cassette l is kept moisture-proof.

Various information about the paper 5 is printed and displayed in the form of a bar code 12 on one side 11 of the front end of the cassette body 3, that is, the insertion section 10. That is, the barcode 12 displays the characteristics of the paper 5 such as its size, paper thickness, talc amount, paper quality, etc., and also displays the initial number of sheets of paper 5 accommodated. Also, the side surface °11
A black bar (dummy bar) 13a for initial position setting is printed on the upper part of the barcode 12, and a black bar (remaining amount display bar) 13 indicating the number of sheets used is written in the blank area behind it. It has become. and the barcode 12
, the dummy bar 13a and the black belt 13 are also protected by the storage M4 when the cassette is not in use.

The paper feed cassette 1 that also serves as a storage case can be configured in various ways. For example, Utsukai Showa 61-5633
As disclosed in Japanese Patent No. 5, it is possible to use a cassette body in which a spring for biasing the push-up plate upward is built into the cassette body.

The paper feed cassette 1a shown in FIG.
It is of a type that has a built-in storage lid 4, and is equipped with a seal plate 14 in place of the storage lid 4. This sealing plate 14 closes the paper feed roller opening 6a and the paper feed liner 9a, thereby preventing moisture inside the cassette main body 3a. When using the cassette, pull out the seal plate 14 and open the paper feed slit 9a.
The paper 5 is supplied from there. Although not shown, on the outer surface of the insertion portion of the paper feed cassette 1a, specifically, on the front end of one side of the cassette main body 3a, there are marks shown in FIGS. 1 to 3.
A bar code and dummy bar similar to those of the paper feed cassette 1 shown in the figure are displayed.

The paper feed cassette 1 shown in FIGS. 1 to 3 is used by being removably inserted into an apparatus main body 2, as shown in FIG. At this time, the storage M4 has been removed, the paper feed roller 16 is in pressure contact with the upper surface of the vapor 5 entering the inside of the cassette body 3 through the feeder opening 6, and the push-up roller 17 enters the inside of the cassette body 3 through the lower push-up roller and comes into elastic contact with the lower surface of the push-up plate 8, thereby pushing up the push-up plate 8.

Then, due to the rotation of the paper feed roller 16, the paper 5
are supplied to the apparatus main body 2 one by one.

As shown in FIGS. 2, 5, and 6, a code reading means 22 for reading the bar code 12 is provided in the cassette insertion portion 21 of the main body 2 of the apparatus. In this example, L
The code reading means 22 is composed of a light projector 28 made of an ED and a light receiving sensor 29 that detects the light emitted from the light projector 28 and reflected by the bar code 12.

The code reading means 22 is configured to be movable in the direction of the arrow in FIG. 6 so that all information on the barcode 12 can be scanned. That is, the code reading means 22 is controlled by a motor control circuit 24 and is constructed by attaching a light projector 28 and a light receiving sensor 29 to a moving body 26 driven by a stepping motor 25.

The code reading means 22 scans itself, and as shown in FIG. It is also possible to use the movement of the barcode 12 when it is inserted to read all the information on the barcode 12.

A black belt reading means 23 (FIG. 2) having a structure similar to that of the code reading means 22 is disposed near the top of the code reading means 22. The black belt reading means 23 is connected to a black belt writing means 30 (described later), and scans to detect the length of the black belt 13.

The black belt 13 is written on one side 11 of the insertion section IO of the paper feed cassette 1 according to the number of sheets of paper used,
Its length is proportional to the number of sheets of paper used. As a means for writing this black band 13, a thermal transfer method is used, as shown in FIG. The black band writing means 30 has a print head 32 with an ink ribbon 31, which is driven by a stepping motor 34 controlled by a motor control circuit 33 to move in the direction of the arrow. The black belt reading means 23 reads the rear end position of the black belt 13, and based on this black belt rear end detection signal, the print head 3 is moved to the rear end position.
2 moves, and then the print head 32 additionally writes a black band 13 of a length corresponding to the number of sheets of paper used.

The black belt writing means 30 is an example of a means for writing information corresponding to the number of sheets of paper used on the outer surface of the paper feed cassette 1, but other writing means such as a dot method or an exposure method may also be used. It is also possible to display the information using a display means other than a black band. Note that the first writing of the black belt 13 is performed by detecting the rear end of the dummy bar 13a and continuing therefrom.

The basic structure of the main body 20 of the copying machine includes the paper feed cassette 1.
This is a general method for copying an image of a document onto paper 5 supplied from a paper 5, and its explanation will be omitted.

FIG. 9 shows a configuration diagram of a microcomputer that controls the main body 2 of the apparatus. A microprocessor unit (hereinafter referred to as MPU) 40 receives a barcode signal from the code reading means 22 and a black belt trailing edge detection signal from the black belt reading means 23. In addition, an empty sensor 43 Signals from the switch, key 41 (No. 8), and other sensors 42 are also input.

On the other hand, the MPU 40 outputs signals for controlling the black belt writing means 30 and the black belt reading means 23, and outputs an empty notice signal to the empty notice display section 44. Further, a signal indicating the number of remaining sheets of paper, etc. is output to the other display section 45. Furthermore, signals for controlling the paper conveying section 46, the optical system section 47, the image forming section 48, the developing and fixing section 49, etc. are outputted, and an empty operation prohibition signal, which will be described later, is outputted.

The device main body 2 is controlled according to the program stored in the memory of the MPU 40.

FIG. 10 is a flowchart showing the main program. The program starts when the power is turned on, and in step #1, the MPU 40 and the device main body 2 are initialized. Next, in step #2, MPIJ40
Controls the output load and input load connected around the device.

Thereafter, copying operation processing (step #3), paper information input processing (step #4), and black band printing processing (step #5)
, remaining paper number determination processing (step #6), cassette unusable processing (step #7), and cassette unusable detection processing (step #8) are sequentially executed. These will be explained in detail later.

In step #9, processes other than those described above, such as toner replenishment and display on the operation unit, are performed. Then step #lO
Then, it is determined whether the internal timer of the MPIJ 40 (reset and started in step #2) has finished counting, and this determination is repeated until the count is finished, and after the count is finished, the process returns to step #2. As a result, the time required for one operation of this main routine is set to a substantially constant time. This main routine is then executed repeatedly.

The copying operation process in step #3 is executed according to the subroutine shown in FIG. Since printing has not started when the power is turned on, this is determined in step #31, and the process returns to the main routine without performing any substantial processing. A detailed explanation will be given later.

FIG. 11 shows a subroutine for paper information input processing in step #4. This subroutine is for the apparatus main body 2 to read the information displayed as the barcode 12, and to prohibit the use of paper feed cassettes outside the scheduled range based on this information.

In step #41, the information on the barcode 12 is sequentially read by scanning by the code reading means 22. Then, in step #42, the information is analyzed,
The paper characteristics (size, paper thickness, talc amount, paper quality, etc.) of the paper 5 in the paper feed cassette 1 are determined, and the initial number of sheets accommodated is determined. Further, this analyzed information is stored in memory. Based on the information thus stored, the copying operation process of step #3 (FIGS. 1θ and 16) is performed. That is, based on the paper characteristics, copying (image formation) is performed by appropriately setting conditions such as image forming range, charging, transfer, developing bias, exposure, and fixing temperature.

As a result of analyzing the information, if the information is outside the planned range, or if the barcode 12 is not displayed on the paper feed cassette 1 and no information can be read, step #43 It is determined that there is an error in the information, and the process proceeds to step #44, where the copying operation (image forming operation) is prohibited. That is, when it is determined that an unscheduled paper feed cassette 1 is being used, its use is prohibited. On the other hand, if it is determined in step #43 that there is no error in the information, the process returns to the main routine.

FIG. 12 shows a subroutine for black band printing processing in step #5. This subroutine is for additionally writing a black band 13 on one side 11 of the insertion section 10 of the paper feed cassette 1 according to the number of sheets of paper used.

When one sheet of paper 5 has been copied, it is determined in step #51 whether or not a copy end signal has been received. If the copy end signal has been received, the process proceeds to step #52. In step #52, the above-mentioned The end of the black belt 13 is detected by the black belt reading means 23. Based on this detection result, the black band writing means 30 moves to the end position, additionally writes a black band with a width corresponding to one sheet of paper (step #53), and returns to the main routine. Note that even when using a new paper feed cassette 1, a black band (dummy bar) 13a for setting the initial position is printed on the paper feed cassette 1, so detecting this end will prevent any hindrance to the above work. It is carried out without any problems. If the copy end signal is not received in step #51, the process returns to the main routine.
Turn on.

FIG. 13 shows a subroutine for determining the number of remaining paper sheets in step #6. This subroutine detects the length of the black belt 13 written by the black belt writing means 30, determines the number of remaining sheets of paper based on this, and displays this externally or displays a paper empty notice. It is for.

In step #61, the black belt reading means 23 is scanned to detect the rear end position of the black belt 13. Based on this, in step #62, the number of paper sheets to be used corresponding to the effective length of the black belt 13 is calculated, and a comparison calculation is performed with the initial number of sheets stored in the memory to calculate the remaining number of paper sheets. do. Next, in step #63, it is determined whether the number of remaining sheets of paper is equal to or less than a predetermined number of sheets. If it is determined that the number of sheets is less than the predetermined number, in step #64, a preview display signal is output to the empty notice display section 44 to display a paper empty notice. After that, the process moves to step #65. On the other hand, if it is determined in step #63 that the number of sheets is greater than the predetermined number, the process jumps to step #65.

In step #65, a display signal indicating the number of remaining sheets of paper is output to the display section 45, and the number of remaining sheets of paper is displayed. Then return to the main routine.

FIG. 14 shows the subroutine of the cassette unusable process in step #7. This subroutine is for writing a use prohibition mark in order to prohibit the reuse of the paper feed cassette 1 that is empty of paper.

In step #71, it is determined whether the paper is empty based on the signal from the paper empty sensor 43, and if the paper is not empty, the process returns to the main routine. On the other hand, if it is determined in step #71 that the paper is empty, in the next step #72, the end of the black belt 13 that has already been written is detected by the black belt reading means 23.

Based on this, in step #73, the black belt writing means 30 writes a wide black belt (unusable mark).
is additionally written from the end.

When the black band 13 of a predetermined length or more is written on the outer surface of the paper feed cassette 1 in this way, the paper feed cassette 1 cannot be reused, as will be explained in step #8. Then return to the main routine.

FIG. 15 shows the subroutine of the cassette unusable process in step #8. This subroutine is for detecting and determining whether or not a black band 13 of a predetermined length or more has been written, as described above, and prohibiting the reuse of the paper feed cassette 1 that is empty of paper.

In step #81, the black belt 1 is read by the black belt reading means 23.
3 is detected, and then in step #82 it is determined whether the length is equal to or greater than a predetermined length. If it is determined that the length is shorter than the predetermined length, the process returns to the main routine, and if it is determined that the length is greater than or equal to the predetermined length, the process proceeds to step #83. In this step #83, a prohibition signal for prohibiting a copying operation (image forming operation) is sent to the paper conveying section 46 and the image forming section 4.
8, etc., and outputs the display signal to the display section 45. As a result, the use of the empty paper cassette 1 is prohibited, and a message to that effect is displayed. Then return to the main routine.

The copy operation process in step #3 is executed according to the subroutine shown in FIG. 16 as described above, and the barcode 12
Based on the information read from the printer, image forming conditions are set to suit the paper characteristics such as paper size, paper thickness, talc amount, paper quality, etc., and copies are made.

In step #31, when a signal to start printing is received from the switch or key 41 of the operation unit, etc., and it is determined that printing is to start, based on the information, step #32
Copying operation control is performed in . That is, the paper conveyance section 4
6. Control signals are outputted to the optical system section 47, image forming section 48, developing and fixing section 49, etc. so that these sections operate under image forming conditions suitable for the paper characteristics, and are also operated. Thereby, conditions such as image forming range, charging, transfer, developing bias, exposure, fixing temperature, etc. are appropriately set, and copying is performed. Then return to the main routine.

The present invention can be configured in various ways other than those shown in the above embodiments. For example, in the embodiment described above, the MPU 40 is configured to display the initial number of paper sheets accommodated in the paper feed cassette 1 using the barcode 12 and read this to detect the initial number of paper sheets accommodated. If the main body 2 of the apparatus is configured such that only a paper feed cassette with a certain initial number of sheets can be used, the number of sheets M can be determined in advance.
It can also be stored in the PU 40.

In the above embodiment, the black belt writing means 30 writes a black belt 1 every time one sheet of paper 5 is used on the outer surface of the paper feed cassette 1.
3 is configured to additionally write, but if the predetermined number of sheets (
For example, the black belt 13 can be additionally written for every 5 sheets, or after a series of copying operations are completed, the black belt 13 can be additionally written with a width corresponding to the number of sheets to be used. Note that information corresponding to the number of paper sheets may be written by means other than the black belt 13.

Further, in the above embodiment, the black belt 1 is read by the black belt reading means 23.
Although the number of paper sheets used is detected by reading the length of 3, the number of paper sheets used may be detected by other reading means.

Furthermore, in the embodiment described above, the number of remaining paper sheets is determined in the microcomputer-controlled paper remaining number determination process (step #6), and based on this, the remaining paper number is displayed and the paper empty notice is displayed. is not limited to the above, and its application examples are not limited to displaying the number of sheets and displaying a paper empty notice.

(Effects of the Invention) Since the image forming apparatus of the present invention has the above-described configuration and operation, it is possible to easily and easily determine the number of remaining paper sheets in the paper feed cassette that also serves as a storage case, making it difficult to check the remaining number of sheets from the outside. Accurate information can be obtained using compact detection means.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is a perspective view showing the paper feed cassette with the storage lid removed, and FIG. 2 is a sectional view showing the paper feed power center inserted into the main body of the device. FIG. 3 is a perspective view showing the paper feeding power center when it is not in use, FIG. 4 is a sectional view showing another aspect of the paper feeding cassette, FIG. 6 is a plan view thereof, FIG. 7 is a plan view showing another embodiment of the code reading means, and FIG.
The figure is a plan view showing the black belt writing means, FIG. 9 is a block diagram of microcomputer control, and FIGS. 10, 11, 12, 13, 14, 15, and 16 respectively. It is a flowchart of a control means. 1-------・Paper cassette that also serves as a storage case 2-
・-・Device body 13--Black belt (information according to the number of papers) 2
3--------・Black belt reading means (means for reading information)
30-----Black belt writing means (means for writing information) Fig. 2 Fig. 4 Fig. 8 Fig. 9 Fig. 11 Fig. 12 Fig. 13 Fig. μ Fig. 15 Fig. 16

Claims (1)

[Claims] (1) A paper feed cassette with a fixed initial number of paper sheets that can be accommodated and which also serves as a storage case, a means for writing information corresponding to the number of used paper sheets on the outer surface of the paper feed cassette, a means for reading the information, and a reading device. an image forming apparatus, comprising means for determining the number of remaining sheets of paper in a paper feed cassette based on information obtained from the paper feed cassette.