Abstract:
A facsimile machine performs a printing operation in an optimum environment by detecting the environment of the facsimile machine when it receives a facsimile signal from a remote device. A control circuit assembly ( 1 ) of the facsimile machine includes a scanner unit ( 15 ), a printing unit ( 20 ) and a transmission and reception unit ( 25 ). All of them are operated by commands from a main controller ( 2 ). A memory ( 5 ) that accumulates image information is associated with the main controller ( 2 ). If the image information is input into the transmission and reception unit ( 25 ), a fan ( 11 ) and a heater ( 12 ) are operated in accordance with control information stored in a table ( 31 ) prepared in the memory ( 5 ) until attainment of the operation-assured environment. After that, the printing unit ( 20 ) prints the information on sheets of paper. By pressing a button ( 8 ), the printing is forcibly output at whatever time.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     The instant application claims priority under 35 USC 119 of Japanese Patent Application No. 2000-90289 filed on Mar. 29, 2000, the entire disclosure of which is incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an apparatus, like a facsimile, for printing received image information on a sheet of paper, and particularly relates to an apparatus that performs the printing after fulfilling the environmental condition adapted to printing operation. The present invention is also related to an image forming method employing said apparatus. 
     2. Description of the Related Art 
     A facsimile machine generally includes a scanning unit to scan an image of a document, a communication unit to transmit and receive image information through telephone lines or cables, and a printing unit to produce the received image information output on a sheet of paper. Like an image forming apparatus using electrophotographic process, said printing unit often employs a transfer device to transfer a toner image to a sheet of paper and a fixing device to fix it. As an electrophotographic copier does, a facsimile machine applying said electrophotographic process uses a method to form an electrostatic latent image by irradiating a photoconductive drum with light in accordance with received image information, to cause a toner to adhere onto the latent image and to transfer a toner image to paper so as to make the printing. 
     A copier in general is used in limited time and easily able to set the optimum operating condition through the warm-up by switching on in the morning to drive the fix units and by stopping the cooling fan. Meanwhile, since a facsimile machine frequently receives data while nobody is near around like in the night-time, it prints signals without adjusting the environmental condition such as temperature or humidity to the optimum condition for printing, and cannot secure good image quality enough. In order to clear the aforesaid problem of degraded image quality, there is given a proposal to operate the apparatus so as to adapt to the condition appropriate to print when the apparatus receives the facsimile information; however, it sometimes requires long time to secure the optimum condition or occasionally it cannot secure the optimum condition under some environmental condition. 
     SUMMARY OF THE INVENTION 
     One object of the present invention is to provide an image forming apparatus that can eliminate the above-described problems. 
     According to one aspect of the present invention, there is provided an image forming apparatus including a receiving unit to receive image information, a printing unit to print the image information on paper, and a memory to keep the received image information. This image forming apparatus is adapted to keep the received information in the memory if the environment condition is not optimum when it receives the image information. The apparatus sets the optimum condition by driving the apparatus for a predetermined period without printing, and print the image from the memory after that. The printing operation is effected after the optimum condition is attained so that decent printing quality is promised. 
     The environment condition may be temperature and/or humidity. A heater and/or a fan in the printing unit may be driven to obtain the optimum condition. The apparatus may include a display for indicating a fact that the environment condition is optimum or not. 
     The received image information may be retrieved from the memory and printed on a sheet if a user directs to print it. The user can direct the printing operation even prior to fulfilling the optimum condition. The use is therefore able to obtain the printed image when he or she wants it. 
     The received image information may be retrieved from the memory and printed after the image forming apparatus is driven for a prescribed period regardless of a fact that the optimum condition is reached or not. By doing so, it is possible to prevent the received image information from being accumulated in the memory for a long period without printing. 
     According to another aspect of the present invention, there is provided an image forming method including the steps of receiving image information, accumulating the received image information in a memory, detecting an environmental condition, determining whether the detected environmental condition is an optimum one or not, driving at least one element in an apparatus for a predetermined period if the detected condition is not determined the optimum one, printing the image information accumulated in the memory after the predetermined period elapses or after the detected condition is determined the optimum one. 
     If a printing command is input by a user, the printing is effected regardless of the detected environment condition. 
     Additional objects, aspects and advantages of the present invention will become apparent to those skilled in the art to which the present invention relates from the subsequent description of the embodiment(s) and the appended claims, taken in conjunction with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
     FIG. 1 illustrates a circuit diagram of a control circuit assembly employed in a facsimile machine according to the present invention. 
     FIG. 2 is a flowchart showing the operation of the control circuit assembly shown in FIG.  1 . 
     FIG. 3 is a control table employed in the control circuit assembly. 
     FIG. 4 is similar to FIG.  2  and illustrates a modified operation of the control circuit assembly. 
     FIG. 5 is also similar to FIG.  2  and shows still another modified operation of the control circuit assembly. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Embodiments of the image forming apparatus according to the present invention will. now be described with reference to the accompanying drawings. A facsimile machine is described below as the image forming apparatus. 
     Referring to FIG. 1, illustrated is a structure of a control circuit assembly  1  employed in a facsimile machine. The control circuit assembly  1  includes the following elements, units and devices in order to control these elements and units individually or in cooperation. Specifically, the control unit assembly  1  includes a scanner unit  15  to scan an image of a document, a printing unit  20  to make a copy of the received image, and a transmission and reception unit  25  to transmit and receive the image information through a telephone line  29 . A main controller  2  providing individual or cooperative control for each unit connects to a power supply unit  3 , a sensor  4 , a memory  5 , a operation unit  6 , and a control interface  10  (hereafter called I/F), and controls every operation in accordance with the control information set in the memory  5 . In addition, the memory  5  has a function to accumulate and keep the image information scanned from an image of the document and the received image information. As described below, the main control circuit  2  also has a function of controlling the printing operation on paper by determining whether the environmental condition suits the printing upon receiving image data from a remote facsimile machine. 
     An operation unit  6  connected to the main control circuit  2  includes a display  7  and a set of input buttons  8 . The display  7  displays the operation state of facsimile, the accumulative condition of the received information, and the reserved print on paper. I/F  10  is installed as a control means for a fan  11  and a heater  12  located in the apparatus, and is used to make adjustments to the inside environment of the apparatus in accordance with the outside environment of the apparatus like temperature or humidity measured by the sensor  4  and/or the inside environment of apparatus measured by sensors or detectors installed in the apparatus. The fan  11  has a function to exhaust the inside air of apparatus, and works as an exhaust fan while a copier module in the apparatus is operated. The heater  12  may be a heating roller of a fix unit and the heat emitted from the roller warms the inside of the apparatus. Alternatively, a separate heater may be provided to warm the interior of the apparatus. 
     A control I/F  16  is installed in the scanner unit  15  of the facsimile machine to control the operation of the scanner unit  15 . The control I/F  16  is connected to a drive unit  17  to drive an image sensor  18  and an image processing circuit  19  to process the image information obtained from the image sensor  18 . The image information obtained from the image sensor  18  is temporarily stored in the memory  5 , so that the information stored in the memory  5  may be transferred to the transmission and reception unit  25  in the case of the transmission over the telephone line  29  by way of the transmission and reception unit  25 . 
     The printing unit  20  has a printing function of a general copier and includes an image processing unit  23  to control the function of image writing onto a photoconductive drum, a paper feed device  24  including a drive means like a roller for paper feeding, and a drive unit  22  to drive the unit and device. The main control circuit  2  controls the unit and device through a control I/F  21  and prints an image on a sheet of paper. The transmission and reception unit  25 , including a modem  27  and a transmission and reception circuit  28 , is controlled by the main control circuit  2  through a control I/F  26  and transmits and receives the image information over the telephone line  29 . 
     Each function installed in the control circuit assembly  1  is described on the assumption that the function is for a facsimile machine; however, the present invention (control circuit assembly  1 ) can be employed in an image forming apparatus that is a complex of a copier and a facsimile machine. For instance, in the case that only the function of a copier is operated to print on paper in accordance with the image information scanned from the document, the scanner unit  15  and the printing unit  20  are only caused to operate. In such a case, the operations of the fan  11  and the heater  12  are controlled through the control I/F  10  in order to set the optimum environmental condition for printing and the print operation is performed under the optimum condition. 
     In the case of the facsimile reception with the control circuit assembly  1 , the main controller  2  controls to print on paper in accordance with conditions shown in the flowchart of FIG.  2 . As depicted, when a facsimile signal is received, it is determined at Step a-1 whether a current environment condition reaches an operation-assured environment. If the environmental condition is satisfied, the program proceeds to Step a-2 such that a printing operation is carried out and the printed paper is produced. Unless the environmental condition is satisfied at Step a-1, the display  7  shows the warning message at Step a-3, and it is determined at Step a-4 whether a user operation for the printing operation is made or not. If the printing operation is forcefully instructed by the user regardless of the environmental condition, the display of warning message on the display  7  is cancelled at Step a-5 and printing is made on paper at Step a-2. 
     If the user operation is not set at Step a-4, the heater  12  and the fan  11  are driven at Step a-6 and a-7 respectively. One or both of the heater  12  and the fan  11  are driven for a predetermined period (Step a-8). After the time elapses longer than the predetermined period, which is set in a control table  31  of the memory  5  beforehand, the heater and/or fan is deactivated and the program proceeds to Step a-2 through Step a-5 in order to print on paper. It should be noted that even if the condition is satisfied at Step a-8, the program may not advance to Step a-2 immediately; instead, the printing unit may be kept in a stand by mode until the printing command is input by the user. In that case, the printing operation is performed only when the command of printing (the user operation of Step a-4) is set. 
     Referring to FIG. 3, illustrated is the control table  31  set in the memory  5 , which is used as the control information for the heater  12  at Step a-6 and for the fan  11  at Step a-7. The control table  31  provides the operation time of the fan  11  and the heater (fix unit)  12  with respect to the environmental condition detected by the set of sensors  4 . For example, on condition that a temperature is X° C. and the humidity is Y%, the operation time of the fix unit (the heating time of the heat roller) is set as αsec and that of the fan is βsec. If the exact temperature and/or humidity is not indicated in the table  31 , the operation times of the fix unit  12  and the fan  11  are decided according to the proportional distribution among the data in the control table. Accordingly, the environmental condition inside the apparatus is automatically set to be the optimum condition for printing. It should be noted that the control table  31  of FIG. 3 is applicable to other embodiments described below. 
     Another embodiment will be described in reference to FIG.  4 . Steps b-1 through b-7 are the same as Steps a-1 through a-7 in FIG.  2 . After the fan  11  and the fix unit  12  are operated for respective periods, which are determined from the control table  31 , Step b-8 determines whether the operation-assured environment is achieved or not. If the inside environment of the apparatus is judged suitable for printing, the alarm message is deleted at Step b-5 and the printing is operated at Step b-2. If Step b-8 concludes that the operation-assured environment is not achieved, the environmental information regarding the inside temperature and humidity of the apparatus on that occasion is measured by the sensor  4 , and the operations set in Steps b-6 and b-7 are repeated again during the times that are newly obtained from the control table  31 . Thereafter the program proceeds again to Step b-8 to determine whether the operation-assured environment is satisfied. If the answer is yes, the program proceeds to Steps b-5 and b-2. 
     A still another embodiment is illustrated in FIG.  5 . According to this flowchart, the received facsimile information is accumulated in the memory  5  if the operation-assured environment is not satisfied at the time of the facsimile information reception, and the printing operation is performed after the user instructs so. Similar to the first and second embodiments, it is determined at Step c-1 whether the operation-assured environment is satisfied or not when the facsimile information is received, and at Step c-2 the printing is carried out if the environment is considered to be the optimum one. When Step c-1 decides that the condition is not met, a warning message is displayed at Step c-3 and the next operation is on hold until the input of user operation at Step c-4. If the user presses the button  8 , the warning message is deleted at Step c-5 and the printing is operated at c-2. If the user does not touch the input button  8  at Step c-4, the received facsimile information is kept in the memory  5 . However, the printing can be operated at Step c-2 after the satisfaction of the operation-assured environment is detected through the detection of it in Step c-1 at whatever time. 
     The apparatus can have one or more flowcharts shown in FIGS. 2 to  5 , and a user freely can choose one of them for the operation. For example, at an office in the cold latitudes with extremely low ambient temperature in the night time when nobody is there, if the operation of FIG. 5 is selected, it is not necessary to warm up the apparatus and print the facsimile information whenever received, but the apparatus can print the received facsimile information at whatever time after the working time begins in the office and the copier is used. This control contributes to energy savings. The present invention is applicable to a facsimile machine or a complex apparatus which is connected to computers or servers through the network such as LAN if the apparatus prints out the data received from the computers. In such a case, energy savings is also attained.