Image recording apparatus with the ability to determine if enough expendable supplies are available to carry out a recording job

An image recording apparatus using expendable supplies, the apparatus including a rotary portion of the paper tray for detecting the amount of expendable supplies which are available for use during image recording, a similar rotary portion of the document tray or an automated document feeder capable of counting sheets of paper for calculating the quantity of expendable supplies necessary for the selected recording operation, a comparator for comparing the detected amount with the calculated amount, and a display for informing an operator of the result of comparison.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to an image recording apparatus, suitable for 
use in a digital copying machine, or the like, of the type in which an 
image of a document is read and stored, and in which the stored image 
information is recorded. The invention particularly relates to an image 
recording apparatus capable of judging, prior to execution of the 
recording operation instructed by an operator, as to whether there are or 
are not expendable supplies such as recording sheets, or the like, in the 
amount required for the chosen recording operation, and the invention 
further relates to an apparatus capable of preventing interruption of the 
recording operation because of a shortage of expendable supplies. 
2. Discussion of the Related Art 
Recently, with the spread of personal computers and word processors, etc., 
the types of image information to be copied, or likewise processed, has 
become diverse and large in quantity. 
To cope with this phenomena, improvements in the quality of copied images 
has been necessary. Also, it has been necessary to increase flexibility 
and functions of copying machines over the traditional functions of number 
of copies and scale reduction/ enlargement. 
Examples of the various functions which have been required in copying 
machines include electronic recirculating document handling (hereinafter 
abbreviated to "electronic RDH") in which a plurality of documents are 
copied a desired number of times for each document; and bookbinding in 
which images of a plurality of documents are suitably edited and copied in 
a manner so that images of two documents are copied on opposite ends of a 
sheet of recording paper so as to make a two page sheet, the sheets of 
recording paper on which images have been copied are stacked, and the 
stack is bound at the center and doubled into booklet in which the copies 
of the documents are arranged in the order of pages. 
Other examples of functions which have been required in copying machines 
include image communication as in facsimile equipment, and printing for 
outputting information from a host computer, a personal computer, or the 
like. 
Conventionally, copying machines in which the above-mentioned functions are 
available have been the so-called digital copying machines. In such a 
digital copying machine, documents are set in an automatic document feeder 
(hereinafter abbreviated to "ADF"), and the documents are automatically 
successively fed by the ADF onto a platen of the copying machine so that 
the image on each document is read by a scanner and stored in a storage 
device after it is converted into an electric signal. 
Depending on the copying function designated by an operator, the image 
information of a document stored in the storage device is read out from 
the devise and converted into optical image information by a raster output 
scanner (hereinafter abbreviated to "ROS") unit so that image recording 
can be carried out through known electrophotographic copying processes. 
During the electrophotographic copying process, at the time of image 
recording, expendable supplies such as recording sheets, toner, etc., 
stored in the copying machine are consumed. Accordingly, it is desirable 
to provide a digital copying machine with a function to detect and 
indicate existence of the expendable supplies. 
If the copying machine is used as facsimile equipment, image information 
transmitted through a telephone line is stored in the storage device, and 
then the stored information is read out from the storage device and 
converted into an optical image by means of the ROS, or the like, so that 
image recording can be carried out through known electrophotographic 
copying processes. 
On the other hand, when the above digital copying machine is used as a 
printer, image information transmitted from a host computer, or the like, 
is stored in the storage device, and then the information is read out from 
the storage device and converted into an optical image by the ROS, or the 
like, so that image recording can be carried by known electrophotographic 
copying processes. 
In the copying machine discussed above there is the following problem. The 
prior-art digital copying machines have no function to detect and indicate 
the amount of expendable supplies such as recording sheets, toner, and the 
like, although they do have a function to detect and indicate the 
existence of expendable supplies such as recording sheets, toner, and the 
like. 
Further, digital copying machines have, in addition to an ordinary document 
copying functions, various complicated functions such as an electronic RDH 
function in which a desired number of copies is made of plurality of 
documents and so on. Accordingly, it is it is difficult for an operator to 
estimate the amount of expendable supplies such as recording sheets, and 
the like, required for execution of a designated job based upon the number 
of sheets of documents and whether a function such as RDH or the like is 
to be executed. Sometimes, the expendable supplies, such as recording 
sheets, or the like, become used up during the copying operation. If the 
supplies are used up, the copying machine interrupts the copying operation 
and indicates the used-up state of the expendable supplies such as paper 
or toner, and thereby calls upon the operator to supplement the supplies. 
After the operator supplements the expendable supplies and pushes the 
start button again, the digital copying machine restarts the interrupted 
copying operation. 
However, digital copying machines have complicated functions such as RDH, 
bookbinding, in addition to an ordinary document copying function. 
Accordingly, if sheets of recording paper, for example, become used up 
during the RDH function, the remainder portion of the job is restarted 
after additional recording paper is added. Therefore, the operator must 
examine the remaining number of pages of the documents for which the 
copying operation has been interrupted, and the remaining number of sheets 
of recording paper on which the copies are to be made so as to designate, 
on a control board, the number of pages of the documents, the number of 
sheets of recording paper, etc., on which the copying operation is 
restarted. Thus, the operation to start copying operation again after 
interruption of the copying operation is troublesome. 
If the digital copying machine has the capability to act as facsimile 
equipment or a printer, there is sometimes a not-yet finished portion of a 
job stored in the storage device within the copying machine when an 
operator newly designates another job to be executed. In such a case, even 
if there is a sufficient quantity of expendable supplies such as sheets of 
recording paper, or the like, in the copying machine for execution of the 
job newly designated by the operator, the expendable supplies consumed by 
the not-yet finished job (for example, image recording for an incoming 
facsimile) so that the remaining quantity of the expendable supplies 
becomes inadequate to execute the job newly designated by the operator. 
In this case, even if the quantity of expendable supplies such as sheets of 
recording paper, or the like, within the copying machine is examined, it 
is impossible to judge whether the newly designated job can be executed by 
the examined quantity of expendable supplies. Accordingly, in some cases, 
expendable supplies such as sheets of recording paper, or the like, may be 
used up in the copying operation so that the copying operation is 
interrupted. Also in this case, as described above, when copying operation 
is restarted after interruption of the copying operation, the operator is 
required to perform a complicated operation to examine the remaining 
number of pages of the documents, the remaining number of sheets of 
recording paper, etc., for which copying operation has been interrupted 
and to designate through control board the number of pages of the 
documents, the number of sheets of recording paper, etc., on which the 
copying operation be restarted. Thus, also in this case, the operation to 
start copying operation again after interruption is troublesome. 
SUMMARY OF THE INVENTION 
The present invention has been made in view of the above circumstances and 
has an object to provide an image recording apparatus in which, when a job 
is to be executed, the operator can confirm whether or not the expendable 
supplies are sufficient for execution of the job are available within the 
copying machine, thereby preventing the job from being interrupted because 
of a shortage of supplies. 
Additional objects and advantages of the invention will be set forth in 
part in the description which follows and in part will be obvious from the 
description, of may be learned by practice of the invention. The objects 
and advantages of the invention may be realized an attained by means of 
the instrumentalities and combinations particularly pointed out in the 
appended claims. 
To achieve the above object and in accordance with the purpose of the 
invention, as embodied and broadly described herein, the invention 
comprises an image recording apparatus using expendable supplies, the 
apparatus performing a selectable recording operation, the apparatus 
comprising means for detecting the amount of expendable supplies which are 
available for use during image recording, means for calculating the 
quantity of expendable supplies necessary for the selected recording 
operation, means for comparing the detected amount with the calculated 
amount, and means for informing an operator of the result of comparison.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Referring to the drawings, embodiments of the image recording apparatus 
according to the present invention will be described hereunder. 
According to a first aspect of the present invention, the image recording 
apparatus in which an image of a document is read and converted into an 
electric signal so that, after the read image information of the document 
is stored, the image information is read out so as to record the image, 
the apparatus comprises an expendable supplies residue detection means for 
detecting a residue of expendable supplies which are consumed with the 
execution of image recording operation, and an information means for 
informing an operator of the residue of the expendable supplies detected 
by the expendable-supplies residue detection means. 
Further, according to a second aspect of the present invention, the image 
recording apparatus in which an image of a document is read and converted 
into an electric signal so that, after the read image information of the 
document is stored, the image information is read out so as to record the 
image, the apparatus comprises an expendable-supplies residue detection 
means for detecting a residue of expendable supplies which are consumed 
with the execution of image recording operation, an expendable supplies 
consumption operation means for calculating a quantity of consumption of 
the expendable supplies necessary for execution of recording operation 
indicated by an operator, and an information means for comparing the 
residue of the expendable-supplies detected by the expendable-supplies 
residue detection means with the quantity of consumption of the 
expendable-supplies calculated by the expendable-supplies consumption 
operation means and for informing the operator of the result of 
comparison. 
An image recording means used in either image recording apparatus has, for 
example, means in which the read image information is converted into 
optical image information by means of a ROS unit so that image recording 
is carried out through a known electrophotographic copying process. 
However, the present invention is not limited to this, because means for 
recording images by an electrostatic recording system, means for recording 
images by an ink jet recording system, or the like, may be used. 
Expendable-supplies consumed with the image recording operation include 
sheets of recording paper on which image recording is carried out, toner 
by which development of an electrostatic latent image is carried out, and 
so on. 
The above-mentioned expendable-supplies residue detection means has, for 
example, means for detecting the residue of sheets of recording paper, as 
expendable-supplies, accommodated in a paper supply cassette. However, the 
present invention is not limited to this but means for detecting the 
residue of toner accommodated in a developing device, means for detecting 
the residue of ink used in the ink jet recording system, or the like, may 
be used. 
Further, as the above-mentioned expendable-supplies consumption operation 
means, for example, there is used means provided with means for detecting 
the thickness of documents arranged on a document feeding tray. 
Alternatively, as the above-mentioned expendable-supplies consumption 
operation means may be provided with means for detecting the number of 
sheets of read-in documents. Further alternatively, the above-mentioned 
expendable-supplies consumption operation means may have means in which an 
operation is performed so that, in the case where a recording operation in 
execution or a not-yet executed operation is present at a designated point 
of time, the calculation of expendable-supplies consumption is carried out 
by additionally summing up the expendable-supplies consumption necessary 
for the recording operation in execution or the not-yet executed 
operation. 
According to the first aspect of the present invention, the residue of 
expendable-supplies which are consumed with the execution of the image 
recording operation is detected by the expendable-supplies residue 
detection means and the operator is informed, before the start of 
recording operations, by the information means of the detected residue of 
the expendable supplies. Thus, the operator can know the residue of the 
expendable supplies and can make a rough calculation of the expendable 
supplies to be consumed on the basis of the number of documents and the 
contents of recording operation which is to be carried out by the 
operator. Accordingly, by comparing the result of the above rough 
calculation with the residue of expendable supplies informed by the 
information means, the operator can make a judgment as to whether or not 
the expendable supplies necessary for execution of the recording operation 
to be carried out by the operator are present in the apparatus. 
Accordingly, the recording operation designated by the operator can be 
prevented from being interrupted because of shortage of the expendable 
supplies. 
According to the second aspect of the present invention, the residue of 
expendable supplies which are consumed with the execution of image 
recording operation is detected by the expendable supplies residue 
detection means and the quantity of consumption of the expendable supplies 
necessary for execution of the recording operation designated by the 
operator is calculated by the expendable-supplies consumption operation 
means. The residue of expendable supplies detected by the expendable 
supplies residue detection means and the quantity of consumption of the 
expendable supplies calculated by the expendable-supplies consumption 
operation means are compared with each other by the information means so 
that the information means informs the operator of the result of 
comparison. Thus, the operator can easily make a judgment as to whether or 
not the expendable supplies necessary for execution of the recording 
operation to be carried out by the operator are present in the apparatus. 
Accordingly, the recording operation designated by the operator can be 
prevented from being interrupted because of shortage of the expendable 
supplies. 
FIG. 1 is a perspective view showing the exterior of a digital copying 
machine which is an embodiment of the image recording apparatus according 
to the present invention. The digital copying machine is provided with, in 
addition to ordinary functions for making copies of documents, not only a 
function for performing copying on opposite surfaces and multiple copying 
on one-side surface, but an RDH function in which a plurality of documents 
are copied for desired number of sheets for every document under the 
condition of suitable assortment, a bookbinding function in which images 
of a plurality of documents are suitably edited and copied so that images 
of two documents are copied on each of opposite surfaces of a sheet of 
recording paper so as to divide each surface into two pages, the sheets of 
recording paper on which images have been copied are stacked, and the 
stacked sheets are bound at the center thereof and doubled into one 
booklet in which the copies of the documents are arranged in the order of 
pages. 
Generally, the digital copying machine 1 is constituted by an image input 
terminal (hereinafter abbreviated to an "IIT") 2, an image output terminal 
(hereinafter abbreviated to an "IOT") 3, and a controller (hereinafter 
abbreviated to a "CONT") 4 for controlling the operation of the IIT 2 and 
IOT 3. The IIT 2 is arranged to read an image of a document, convert the 
read image into an electric signal, and output the electric signal after 
making fundamental processing such as zigzag correction, or the like, on 
the electric signal. The IOT 3 is arranged to store the image information 
supplied from the IIT 2, record the image information after making 
secondary processing according to demand, and output the image 
information. 
The CONT 4 has a user interface (hereinafter abbreviated to a "UI") 5 
through which an operator can designate copying operation, or the like. 
The UI 5 is provided with a keyboard 6 and a mouse 7 through which an 
operator can designate a copying operation, and a display 8 for displaying 
the contents of the copying operation designated by the operator. 
In this embodiment, the IIT 2 is provided at its upper portion with an 
automatic document feeder (hereinafter abbreviated to an "ADF") 10 for 
automatically feeding a document onto a platen of the IIT 2. 
The ADF 10 is incorporated in a cover unit which openably covers the top of 
the platen of the IIT body as shown in FIG. 1. The ADF 10 includes, as 
shown in FIGS. 2 and 3, a document feed tray 12 for accommodating a large 
number of documents 11 therein in a state that the forward ends of the 
respective documents are made to abut against a side wall 12a, a feed belt 
13 for feeding, one by one, the documents 11 accommodated in the document 
feed tray 12, conveyer rolls 16 for conveying the document 11, which is 
fed by the feed belt 13, to the platen 16 through a paper shoot 14, a 
conveyer belt 17 for conveying the document, which is conveyed by the 
conveyer rolls 16, to a document setting position on the platen 15, 
discharging conveyer rolls 18 for discharging the document 11 sent out by 
the conveyer belt 17 upon the completion of reading the image of the 
document 11 mounted on the platen 15, and a document receiving tray 19 for 
accommodating the discharged documents 11. 
The document 11 fed onto the platen 15 of the IIT body by the ADF 10 is 
read by a scanner 20 of the IIT 2 as shown in FIG. 4. The scanner 20 is 
provided with a light source 21 for illuminating the document 11 mounted 
on the platen 15, a reflection plate 22 for reflecting light from the 
light source 21 toward the document 1, a plurality of mirrors 24, 25, and 
26 for leading the reflection light from the document 11 to an image 
sensor array 23 including Charge Couple Devices (CCDs), or the like, and a 
lens 27 for focusing the image carrying light directed by the mirrors 24, 
25, and 26 onto the image sensor array 23. The light source 21, the 
mirrors 24, 25, and 26, the image sensor array 23, and the like, are 
integrally assembled as the scanner 20 (as shown in FIG. 2) and the 
scanner 20 is driven by a drive mechanism (not shown) so as to be 
reciprocally below the platen 15 in a sub-scanning direction. Further, the 
scanner 20 is arranged so as to read the image of the document 11 mounted 
on the platen 15 by means of the image sensor array 23 while moving below 
the platen 15 in the subscanning direction. 
The image information of the document 11, read by the image sensor array 23 
of the scanner 20, is supplied to a processor 28 so as to be subject to 
fundamental processing such as zigzag correction or the like, and then 
supplied to the IOT 3, as show in FIG. 5. 
After being subject to secondary image processing in accordance with 
requirements, the image information received by the IOT 3 is stored in a 
storage device 30 including a hard disk, a semiconductor memory, or the 
like. The image information stored in the storage device 30 is read out 
from the storage device 30 in predetermined order on the basis of an 
instruction from the UI 5 provided in the CONT 4. The image information 
read out from the storage device 30 is converted into an optical signal 
which is supplied by a raster output scanner (hereinafter abbreviated to 
an "ROS") unit 31 onto a photoreceptor belt 32 through scanning exposure, 
as shown in FIG. 5. 
The ROS unit 31 comprises a semiconductor laser 33 and a polygon mirror 34, 
as shown in FIG. 2, so that a beam from the semiconductor laser 33 is 
reflected by reflection surfaces of the polygon mirror 34 so as to be 
directed onto the photoreceptor belt 32 over a predetermined scanning 
range. 
The ROS unit 31 is arranged so that a laser beam Bm emitted from the 
semiconductor laser 33, which oscillates in accordance with image 
information, is scanned by the polygon mirror 34 in the axial direction of 
the photoreceptor belt 32 so that an image corresponding to the image 
information is transferred onto the photoreceptor belt 32 through scanning 
exposure. 
After the photoreceptor belt 32 is uniformly electrically charged in 
advance by primary chargers 36 so as to have a predetermined electrical 
potential, an image is applied onto the photoreceptor belt 32 by means of 
the ROS unit 31 through scanning exposure as described above, so that an 
electrostatic latent image is formed on the surface of the photoreceptor 
belt 32. 
The electrostatic latent image is developed to form a toner image by a 
developing device 36 using black toner. Then, the toner image formed on 
the photoreceptor belt 32 is transferred, by electrification of a transfer 
charger 41, from the photoreceptor belt 32 onto recording paper 40 of a 
predetermined size supplied from one of a plurality of paper supply 
cassettes 37, 38 provided in the IOT body. More than two paper cassettes 
may be provided. The recording paper 40 on which the toner image has been 
transferred is separated from the photoreceptor belt 32 by a separation 
charger 42 using electrification, and conveyed to a fusing device so that 
the toner image is fused and fixed on the recording paper 40. 
After the completion of the transfer step, the surface of the photoreceptor 
belt 32 is cleaned by a cleaner 44 so that residual toner, paper powder, 
and the like are removed, and the surface of the photoreceptor belt 32 is 
electrified by a static eliminator 45 so that residual charge thereon is 
eliminated. Thus, the photoreceptor belt 32 is made ready for the next 
image recording process. 
The recording paper 40 on which the toner image has been fused as described 
above is discharged as-is onto a discharge tray 46 in the case of a normal 
copy mode. 
In the case of a double-side copy mode, a one-side multiple copy mode, or 
the like, on the contrary, the recording paper 40 on which the toner image 
has been fused is not discharged as-is, but conveyed to the transfer 
section again through a convey path 47 and a paper turn-over mechanism 48 
in the state where the recording paper 40 is left as-is or the front and 
rear surfaces of the recording paper 40 are turned over, so that a 
predetermined toner image is transferred and fused. After repetition of 
such transferring and fusing of predetermined images, the recording paper 
40 is discharged for the first time onto the discharge tray 46. 
In this embodiment, there is provided means for detecting the amount 
(residue) of expendable supplies which are available for recording. As 
embodied herein, the recording paper residue detection means is provided 
in each of the paper supply cassettes 37, 38. As shown in FIG. 6, each of 
the paper supply cassettes 37 and 38 has a paper supply cassette body 51 
which is opened at its upper end surface and is shaped so as to be like a 
relatively thin box. The sheets of recording paper 40 having a 
predetermined size are accommodated in the paper supply cassette body 51 
in the state in which they are stacked one up on one. A side plate 52, on 
which the rear ends of the respective sheets of recording paper 40 are 
abutted is provided in the upright state inside the paper sup ply cassette 
body 51. Further, the paper cassette includes means for sensing the 
thickness of the paper in the cassette, the means herein embodied as a 
bottom plate 53 on which the sheets of recording paper 40 are placed is 
provided on the bottom portion of the paper supply cassette body 51. The 
bottom plate 53 is rotatable about a rotary shaft 54 integrally provided 
with the rear end of the bottom plate 53. The bottom plate 53 is urged 
upward by an arm 56 penetrating an opening portion 55 formed in the bottom 
portion of the paper supply cassette body 61. The uppermost one of the 
sheets of recording paper 40 stacked on the bottom plate 53 is always 
pressed against a feed roller 57. 
Further, a rotary encoder 58 is attached to the rotary shaft 54 of the 
bottom plate 63 provided on the bottom portion of the paper supply 
cassette body 51. The tilt angle of the bottom plate 53 can be detected by 
the rotary encoder 58. 
That is, the rotary shaft 54 of the bottom plate 53 is integrally provided 
with the bottom plate 53 to thereby rotate together with the bottom plate 
53 the tilt angle which changes in accordance with the residue of the 
sheets of recording paper 40. The rotary encoder 58 is mounted on the 
rotary shaft 54 at its end portion. 
As shown in FIG. 7, the rotary encoder 58 includes a rotary disk 59 fixed 
to the rotary shaft 54 and a photo sensor 60 provided so as to sandwich 
the rotary disk 59. As shown in FIG. 8, slits 61 corresponding to binary 
codes, which are different at every predetermined angle .DELTA..theta., 
are circumferentially formed in the rotary disk 59 at its outer 
circumference. The photo sensor 60 comprises plural pairs (four pairs in 
the drawing) of luminous elements 62 and light detection elements 63 
provided so as to be in opposition to each other through the slits 61, of 
the rotary disk 59. When the rotary disk 59 rotates in accordance with the 
tilt angle of the bottom plate 53, the existence of the slits 61, provided 
in the rotary disk 59 is detected by the photo sensor 60, so that the tilt 
angle of the rotary disk 59 is detected in the form of a binary-coded 
electric signal. 
The tilt angle of the bottom plate 53 of each of the paper supply cassettes 
37 and 38 changes in accordance with the thickness, that is, the residue, 
of the sheets of recording paper 40 remaining in each of the paper supply 
cassettes 37 and 38 and the tilt angle of the bottom plate 53 is detected 
as an output signal of the rotary encoder 68, so that the residue of the 
recording paper 40 can be detected. 
Further, in this embodiment, there is provided means for calculating the 
quantity of expendable supplies necessary for execution of the selected 
recording operation. As embodied herein, the calculating means is provided 
with means for detecting the number of documents. The document number 
detection mean 65 is provided in the ADF 5. As shown in FIG. 3, the ADF 5 
is provided with the document feed tray 12 for accommodating lots of 
documents 11 in a state in which the forward ends of the respective 
documents 11 abut against the side wall 12a. The document feed tray 
includes means for sensing the thickness of the paper in the cassette, the 
means herein embodied as arm 66 provided inside the side wall 12a of the 
document feed tray 12 so as to abut the top end of the documents 11 
accommodated in the document feed tray 12. The arm 66 is attached so as to 
be rotatable about a rotary shaft 67 and urged by a spring (not shown) in 
the direction shown by an arrow. When the documents 11 are accommodated in 
the document feed tray 12 in the state in which the forward ends of the 
respective documents 11 abut against the side wall 12a, the arm 66 is 
pressed upward by the upper end of the documents 11 so as to rotate 
counterclockwise in FIG. 3. 
A rotary encoder 68 is mounted on the rotary shaft 67 of the arm 66 
provided in the document feed tray 12 of the ADF 5. The tilt angle of the 
arm 66 can be detected by the rotary encoder 68. 
The rotary encoder 68 is configured similarly to the rotary encoder 58 of 
the recording paper residue detection means shown in FIGS. 7 and 8. 
Accordingly, the tilt angle of the arm 66 of the ADF 5 changes in 
accordance with the thickness, that is, the number of sheets, of the 
documents 11 set in the document feed tray 12 of the ADF 5, and the tilt 
angle of the arm 66 is detected as an output signal of the rotary encoder 
68, so that the number of sheets of the documents 11 can be detected. 
Further, in this embodiment, there is means for calculating the quantity of 
expendable supplies necessary for execution of the selected recording 
operation on the basis of the residue of the sheets of recording paper 
detected by the recording paper residue detection means 50 as described 
above and the recording operation designated by the operator through the 
UI 5, and means for comparing the detected amount with the calculated 
amount and means for informing the operator of the result of the 
comparison. The calculating means, comparison means, and informing means 
are configured so as to be realized by a control circuit of the digital 
copying machine. 
FIG. 9 is a block diagram showing the control circuit of the digital 
copying machine. In the drawing, the control circuit comprises the IIT 2 
for reading out an image of the document 11, for converting the read image 
into an electric signal, for executing basic processing such as zigzag 
correction, or the like, on the image information converted into the 
electric signal, and for producing the processed electric signal, the IOT 
3 for temporarily storing the image information sent from the IIT 2, for 
recording the image after making secondary processing onto the image 
information in case of need, and for outputting the image information, a 
CPU 70 provided in the CONT 4 so as to control the operation of the IIT 2 
and the IOT 3 and having a part of the functions of the 
expendable-supplies consumption operation means and the information means, 
the UI 5 through which a user designates a desired recording operation, 
the storage device 30 for temporarily storing the image information sent 
from the IIT 2, the ADF 10 for automatically conveying the documents 11 
onto the platen 15 of the IIT 2, the rotary encoder 68 of the document 
number detection means 65 provided in the ADF 10, and the rotary encoder 
50 of the recording paper residue detection means provided in the IOT 3. 
In a digital copying apparatus according to this embodiment having such a 
configuration as described above, the residual quality of expendable 
supplies is detected and the operation is controlled on the basis of the 
detection in such a manner as follows. An operator sets the documents 11 
to be copied on the document feed tray 12 of the ADF 10 and simultaneously 
designates the kind of copying operation (job) by use of the keyboard of 
the UI 5 or the like, and then starts the copying operation. 
When the operator has set the documents 11 to be copied on the document 
feed tray 12 of the ADF 10, designated the kind of recording operation 
(job) to be performed through the keyboard 6 of the UI 5, or the like, and 
pressed a start button, the CPU 70 detects the number of sheets of the 
documents to be copied by means of the rotary encoder 68 of the document 
number detection means 65 and simultaneously detects the residual quantity 
of the sheets of recording paper in each of the paper supply cassettes 37 
and 38 by means of the rotary encoder 58 of the recording paper residue 
detection means 50 as shown in FIG. 10 (Step 1). 
The CPU 70 then judges whether paper selection is automatic or not (Step 
2). In the case where the automatic paper selection is designated by an 
operator by use of the UI 5, the CPU 70 drives the ADF 10 so that the 
first document is read (Step 3), and detects the size of the document 11 
to thereby automatically determine the size of the recording paper 40 on 
the basis of the copy magnification or scale designated from the UI 5 
(Step 4). 
After the size of the recording paper 40 is thus determined, or in the case 
where the operator designates the size of the recording paper 40 for 
himself/herself without designating automatic paper selection, the CPU 70 
calculates the quantity of use of the sheets of recording paper 40 having 
the determined or selected predetermined size (Step 5). The calculation of 
the quantity of use of the sheets of recording paper 40 is performed by 
multiplying the number of sheets of the documents 11 detected by the 
document number detection means 65 by the number of copy sheets designated 
by the UI 5. At this time, in the case where a bookbinding function or the 
like is designated, the quantity of sheets of recording paper 40 to be 
used is calculated in accordance with the bookbinding function, or the 
like. 
Next, the CPU 70 judges whether or not a job is being processed or a 
not-yet processed job exists (Step 6). In the case where a job is being 
processed or not-yet processed job exists, the quantity of use of the 
sheets of recording paper 40 necessary for performing the job being 
processes or not-yet processed is added (Step 7). 
After the quantity use of the sheets of recording paper 40 necessary for 
use in the job being processed or the not-yet processed job is thus added, 
or in the case where no job is being processed or no not-yet processed job 
exists, a judgment is made as to whether the sheets of recording paper 40 
corresponding to the obtained required quantity of the sheets of recording 
paper 40 exists in each of the paper supply cassettes 37 and 38 of the IOT 
3 or not on the basis of the signal supplied from the recording paper 
residue detection means 50 (Step 8). 
In the case where the sheets of recording paper 40 existing in the paper 
supply cassettes 37 and 38 of the IOT 3 are not sufficient when compared 
to the required quantity of sheets of recording paper 40 obtained in the 
manner described above, an alarm is displayed on the display 8 of the UI 5 
so as to inform the operator of the existing condition (Step 9). The 
operator judges whether a job is to be started or not (Step 10). When the 
operator selects stoppage of the job, the operator stops the copying 
operation (Step 11). 
On the other hand, when the sheets of recording paper 40 is sufficient when 
compared to the required quantity of sheets of recording paper 40, or when 
the operator selects start of the job, acceptance of the job, the job is 
accepted (Step 12) to thereby start the copying operation in accordance 
with the job designate by the operator. 
Thus, the recording paper residue detection means 50 detects the residual 
quantity of the sheets of recording paper 40 consumed by image recording 
operation, and CPU 70 calculates the quantity of consumption of the sheets 
of recording paper 40 necessary for execution of the recording operation 
designated by the operator. The CPU 70 compares the residual quantity of 
the sheets of recording paper 40 detected by the recording paper residue 
detection means 50 and the quantity of consumption of the sheets of 
recording paper 40 calculated by the CPU 70, and the display 8 of the UI 5 
displayed thereon the result of comparison, so that the operator is 
informed of the result before starting of the recording operation. 
Accordingly, while looking at the display 8 of the UI 5, the operator can 
easily judge whether or not the sheets of recording paper 40 necessary for 
the recording operation to be carried out exist in the apparatus, so that 
the operator can prevent the recording operation designated by 
himself/herself from being interrupted because of shortage of the 
expendable supplies. 
FIG. 11 shows another embodiment of the present invention, in which the 
same portions of the apparatus as those in the above embodiment are 
correspondingly referenced. In this embodiment, a job is started after 
images of documents 11 have been read previously without detecting the 
number of sheets of the documents 11 in the state in which the documents 
11 are set in the ADF 10. That is, in this embodiment, as shown in FIG. 
11, an operator sets the documents 11 to be copied onto the document feed 
tray 12 of the ADF 10, designates the kind of copying operation or job 
through the key board 6 of the UI 5 or the like, and operates the start 
button. Then, the CPU 70 detects the residual quantity of the sheets of 
recording paper 40 in each of the paper supply cassettes 37 and 38 on the 
basis of the signal produced from the rotary encoder 58 of the recording 
paper residue detection means 50 (Step 1). 
Then, the CPU 70 actuates the ADF 10 to start reading of the documents 11, 
and the CPU 70 detects the number of sheets of the documents 11 by 
counting the number of sheets of the documents 11 read by the ADF 10 (Step 
2). 
Next, the CPU 70 calculates the quantity of use of the sheets of recording 
paper 40 having a predetermined size and read by the ADF 10 (Step 3). The 
calculation of the quantity of use of the sheets of recording paper 40 is 
performed by multiplying the number of the sheets of documents 11 detected 
by the ADF 10 by the number of sheets of copies designated by the UI 5. At 
that time, in the case where a bookbinding function, or the like, is 
designated, the quantity of use of the sheets of recording paper 40 
corresponding to the bookbinding function, or the like is, calculated. 
Next, the CPU 70 makes a judgment as to whether any job is being processed 
or any not-yet processed job exists (Step 4). If a job is being processed 
or a not-yet processed job exists, the quantity of use of the sheets of 
recording paper 40 necessary for performing the job be processed or the 
not-yet processed job is added (Step 5). 
Thus, after the quantity of use of the sheets of recording paper 40 
necessary for the job being processed or not-yet processed is added, or in 
the case where no job exists, a judgment is made as to whether or not the 
number of the sheets of recording paper 40 in the paper supply cassettes 
37 and 38 of the IOT 3 insufficient when compared to the required quantity 
of use of the sheets of recording paper 40 calculated as described above, 
on the basis of the signal produced from the recording paper residue 
detection means 50 (Step 6). 
If the number of sheets of recording paper 40 in the paper supply cassettes 
37 and 38 of the IOT 3 is insufficient when compared to the required 
quantity of the sheets of recording paper 40 obtained by calculation, an 
alarm is displayed on the display 8 so as to inform the operator of the 
existing condition (Step 7). The operator makes a judgment whether the job 
is started or not (Step 8), and if the operator selects to stop the job, 
the operator stops the copying operation (Step 9). 
On the other hand, if the number of the sheets of recording paper 40 in the 
paper supply cassettes 37 and 38 of the IOT 3 is sufficient when compared 
to the required quantity of the sheets of recording paper 40 obtained by 
calculation, or if the operator selects to start the job, the job is 
accepted (Step 10) and the copying operation corresponding to the job 
designated by the operator is began. 
Thus, in the case where the apparatus is arranged so that the number of 
sheets of the documents 11 is previously read and detected by the ADF 10, 
it is not necessary to provide document number detection means 65 in the 
ADF 10. Accordingly, the configuration of the apparatus can be simplified, 
resulting in reduction in cost. 
Although the case in which an alarm is displayed on the display 8 of the UI 
5 as the informing means has been described in the above embodiments, the 
present invention is not limited to this, but any means (for example) 
means for informing the operator of shortage of the sheets of recording 
paper with sound, means for informing the operator of shortage of the 
sheets of recording paper by actively inhibiting the operation of the 
apparatus, or the like may be used as the informing means. 
The present invention is constituted by the above configuration and 
operation, so that an operator can make confirmation as to whether 
expendable supplies sufficient to perform the job designated by the 
operator are available inside the apparatus. Thus, it is possible to 
provide an image recording apparatus in which the job designated by the 
operator is prevented from being interrupted because of a shortage of the 
expendable supplies. 
The foregoing description of preferred embodiments of the invention has 
been presented for purposes of illustration and description. It is not 
intended to be exhaustive or to limit the invention to the precise form 
disclosed, and modifications and variations are possible in light of the 
above teachings or may be acquired from practice of the invention. The 
embodiments were chosen and described in order to explain the principles 
of the invention and its practical application to enable one skilled in 
the art to utilize the invention in various embodiments and with various 
modifications as are suited to the particular use contemplated. It is 
intended that the scope of the invention be defined by the claims appended 
hereto, and their equivalents.