JPH0525872U - Equipment - Google Patents

Abstract

(57) [Abstract] [Purpose] An object of the present invention is to provide a facsimile device capable of keeping the print density constant regardless of the type of thermal paper. In a facsimile apparatus equipped with a thermal printer, when the thermal paper P is set in the printer,
Print instruction means for instructing the thermal head 4 to print a predetermined area on the thermal paper P, print density detecting means 9 and C for detecting the density printed on the area, and the print density detecting means. It is characterized by including a changing means 41 for changing the print pulse width or pulse height of the thermal head 4 according to the detection results of 9 and C.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a facsimile machine, and more particularly, to a facsimile machine that can keep a print density constant even when thermal papers having different sensitivities are used.

[0002]

[Prior Art]

 Generally, a facsimile apparatus employs a recording method such as a heat-sensitive method, a thermal transfer method, or an electrophotographic method as a typical image recording method. Among them, the thermal recording method can obtain the recording only by heating the heating element in contact with the thermal paper, and does not require development and fixing. Therefore, the thermal paper used is relatively inexpensive. Therefore, it is widely used in small facsimile machines. Further, the thermal paper used here is usually loaded in a printer as a roll-shaped thermal paper wound around a paper tube.

The coloring principle of the thermal recording method is as follows. The thermal paper has a thermosensitive layer of about 10 μm provided on the base paper, and the electron donor and the electron acceptor in the form of solid fine particles are physically separated through the binder in the thermosensitive layer. Exists in a state. These components do not develop color when heated alone, but when the thermal head comes into contact, both components are heated and melted at the same time, causing a rapid ion-exchange type electron transfer reaction, producing an irreversible colored substance. Of. In the thermal recording system, the received information is recorded by such a coloring principle.

[0004]

[Problems to be solved by the device]

 However, currently used fax machines are obliged to use thermal paper specified by the manufacturer, and if you use thermal paper of another manufacturer that is not specified, printing will be performed due to the difference in sensitivity of the thermal paper. The concentration will be different. It is expected that thermal paper of each manufacturer will be displayed in supermarkets, stationery stores, etc. as the facsimile machine spreads to general households in the future. There may be problems such as deciding whether to purchase other thermal papers or mistakenly purchasing thermal papers from other manufacturers.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a facsimile apparatus capable of keeping the print density constant regardless of the type of thermal paper.

[0006]

[Means for Solving the Problems]

 The present invention is, in a facsimile machine equipped with a thermal printer, a printing instruction means for instructing a thermal head to print a predetermined area on the thermal paper when setting the thermal paper on the printer, It is characterized by comprising a print density detecting means for detecting the density printed in the area and a changing means for changing the print pulse width or pulse height of the thermal head according to the detection result of the print density detecting means. ..

[0007]

[Action]

 According to the above configuration, when the thermal paper is set to the thermal printer equipped in the facsimile machine, the print instruction means instructs the thermal head to print a predetermined area on the thermal paper. To do. Subsequently, the print density detecting means detects whether or not the print density of the thermal paper is within the range of the reference density. When the print density is outside the range of the reference density, the changing means changes the print pulse width or pulse height of the thermal head.

[0008]

【Example】

 An embodiment of the present invention will be specifically described below with reference to the drawings. FIG. 1 is a sectional configuration diagram showing a recording unit in a facsimile apparatus according to the present invention. The recording unit 1 is housed in a part of the frame of the main body of the facsimile apparatus, and the recording unit 1 for the thermal paper P set in a rolled state and the thermal paper P for which reception information has been recorded are recorded. The thermal paper discharge port 2 serves as a discharge port from the outside to the outside, and the following devices arranged between the thermal paper discharge port 2 and the transport line PL of the thermal paper P. That is, a feeding roller 3 provided as a pair of upper and lower rollers for feeding the set thermal paper P forward, and a thermal printer provided for printing received information on the thermal paper P fed out. A head 4 and a cutter 5 provided for cutting the printed thermal paper P at a predetermined position are provided for the transport line PL.

Further, a thermal paper leading edge position detection sensor Se for detecting the set position of the leading edge of the thermal paper P in the reception waiting state is provided at a lower position on the downstream side of the cutter 5 with respect to the transport line PL. At the upper position on the upstream side of the thermal head 4, the CCD 9 for detecting whether or not the print density of the thermal paper P is within the range of the reference density when starting to use the thermal paper P set, and A comparator C is provided. As the thermal paper front end position detection sensor Se, for example, an optical sensor for detecting the light transmittance is used. The functions of the thermal paper front end position detection sensor Se, the CCD 9 and the comparator C will be described in detail with reference to FIG.

On the other hand, the feeding roller 3, the thermal head 4, the thermal head drive circuit 40, the cutter 5, the RAM 6, the operation panel unit 8, the thermal paper front end position detection sensor Se, the CCD 9 and the comparator C are all the CPU 7 and the CPU 7. Connected, each controlled by the CPU 7. FIG. 2 is a flow chart showing a processing procedure from detection of print density to start of printing. First, when the operator sets the thermal paper P to a predetermined position (S1), the feeding roller 3 then feeds the thermal paper P to a predetermined position (S2). Then, when it is confirmed by the thermal paper front end position detection sensor Se that the front end of the thermal paper P has been set to the predetermined position (Yes in S3), the thermal paper P is again fed by the feeding roller 3 (S4). ), The thermal head 4 prints on a predetermined area of the thermal paper P (S5). Subsequently, the print density of the print area is read by the CCD 9, and the comparator C determines whether the print density is higher or lower than the voltage Er corresponding to the reference density (whether it is within the threshold dead zone). (S6). Here, if it is confirmed that the print density is within the range of the reference density (Yes in S6), the feeding roller 3 is turned off when the last portion of the print area passes the cutter 5, The conveyance of the thermal paper P is stopped (S7). Subsequently, the cutter 5 is turned on, and a cut is made to discard the printed portion on the thermal paper P (S8). In this state, the recording unit is in a reception waiting state, and printing is started immediately upon reception (S9).

On the other hand, when it is confirmed that the print density is out of the range of the reference density (No in S 6), when the last part of the print area passes the cutter 5, the feeding roller 3 Is turned off and conveyance of the thermal paper P is stopped (S10). Here, when the operator selects the density of the thermal paper on the operation panel unit 8 (S11), the pulse width of the strobe signal from the strobe generating circuit 41 is changed, and the pulse width applied to the thermal head 4 is changed accordingly. Adjustment is performed (S12). Subsequently, the cutter 5 is turned on, and cutting is performed to discard the printed portion on the thermal paper P (S13). In this state, the recording unit waits for reception, and printing is started immediately upon reception (S14).

Although the pulse width is changed in the above embodiment, the pulse height is not limited to this, and the pulse height can be changed by the voltage. Further, in the above embodiment, the operator selects the density of the thermal paper, but the present invention is not limited to this, and the density of the thermal paper can be automatically selected.

[0013]

[Effect of the device]

 According to the present invention described above, when a thermal paper is set in a thermal printer equipped in a facsimile machine, printing is performed on a predetermined area of the thermal paper according to an instruction from the printing instruction means. .. Regarding the detection of print density whether or not the print is within the range of reference density, if it is confirmed that the print density is automatically detected by the print density detecting means and it is confirmed that the print density is outside the range of reference density, By changing the pulse width and pulse height applied to the thermal head, it is possible to print at a constant density without being affected by the difference in sensitivity even when using thermal paper of other companies.

[Brief description of drawings]

FIG. 1 is a cross-sectional configuration diagram showing a recording unit in a facsimile apparatus according to the present invention.

FIG. 2 is a flowchart showing a processing procedure from detection of print density to start of printing.

[Explanation of symbols]

 4 Thermal Head 40 Thermal Head Drive Circuit 41 Strobe Generation Circuit 9 CCD C Comparator P Thermal Paper

Claims (1)

[Scope of utility model registration request] 1. In a facsimile apparatus equipped with a thermal printer, when a thermal paper is set in the printer, a print instruction means for instructing a thermal head to print a predetermined area on the thermal paper, A facsimile comprising: a print density detecting means for detecting the density printed in the area; and a changing means for changing the print pulse width or pulse height of the thermal head according to the detection result of the print density detecting means. apparatus.