JPH05162364A - Thermal recording device - Google Patents

Abstract

PURPOSE:To prevent the life of a thermal head from being shortened even when a cut line expressing a boundary of a diagram arranged by layout function is drawn. CONSTITUTION:A layout processor 3 arranges various diagram data having different sizes most properly so as to avoid waste of recording paper. At a layout deciding section 7, an optimum arrangement of a diagram data is decided and a cut line showing a boundary of each diagram is generated. A roll paper exchange detector 15 detects an exchange of a roll paper due to out of paper when it occurs. When the roll paper exchange is detected, a reference point changing section 16 renews a value of a reference point P stored in a memory 14. Thus, the position of the cut line is shifted to the line direction and a heat generating resistor of a thermal head 13 for drawing the cut line is changed, Therefore, load is not concentrated on any specific heat generating resistor so that the life of the thermal head may not be affected.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal recording apparatus such as a thermal plotter and a facsimile apparatus using a thermal head in which a large number of heat generating resistors are arranged in a line, and more particularly, a plurality of drawings need not be used for recording sheets. The present invention relates to a thermal recording apparatus that optimally arranges so as to reduce the number and outputs a cut line that indicates a boundary of arranged drawings.

[0002]

2. Description of the Related Art Conventionally, in the field of automatic drafting machines and the like, a thermal recording apparatus using a thermal head has been used along with a pen plotter because of its high speed of drawing, low noise and easy maintenance. As is well known, thermal heads
A large number of heating resistors are arranged in an array. Recently, large thermal plotters such as A0 and A1 sizes have been developed with the development of long heads and advances in assembly technology.

By the way, in the case of mechanical drawings, drawings of various sizes are generally used according to the size of parts, the connecting level of parts, and the like. When these drawings are drawn by a thermal plotter, if the drawings are drawn in the order of inputting the drawing data, the recording paper must be replaced frequently. Further, if drawings of various sizes are continuously output on the maximum size recording sheet, an unrecorded and useless portion will occur on the recording sheet.

Therefore, as shown in FIG. 6, there is also known a thermal plotter having a layout function for automatically recognizing the size of an input drawing and optimally arranging each drawing so that the recording paper 41 is not wasted. .. Known layout functions include a simple layout function of sequentially laying out in the order of input, and a page layout function of temporarily buffering a plurality of drawing data and performing a sorting process to determine an optimum layout. Further, the thermal plotter having this kind of layout function is additionally provided with a function of performing automatic cutting for each drawing size, a function of displaying a cut line indicating a boundary line between the drawings, and the like.

[0005]

In the thermal recording apparatus having the layout function described above, a plurality of drawings are arranged in the line direction of the thermal head 43 as shown in FIG. The line 42 is a straight line extending extremely long in the conveyance direction of the recording paper 41.
In the thermal recording apparatus, when such a long straight line is drawn in the sheet conveying direction, it is necessary to continuously generate heat from the specific heating resistors P1, P2, P3, P4 and P5 of the thermal head 43. In particular, such a cut line has a unique recording position determined according to the paper size. Therefore,
The heat generating resistor that draws the cut line has a significantly longer heating time than other heat generating resistors, and the life of the entire head is determined by the life of the heat generating resistor that draws the cut line.

As described above, in the thermal recording apparatus which displays the cut line by the layout function, there is a peculiar circumstance in which a specific heating resistor is overused in order to draw the cut line. Despite the small number of printed sheets, there is a problem that the life of the entire thermal head is shortened due to the deterioration of a certain part of the heating resistors.

The present invention has been made in view of the above problems. Even when a cut line is drawn together with drawing data,
An object of the present invention is to provide a thermal recording device that can effectively prevent the life of the thermal head from becoming extremely short.

[0008]

SUMMARY OF THE INVENTION A thermal recording apparatus according to the present invention analyzes a drawing data to recognize a drawing size, and records a plurality of drawings based on the drawing size recognized by the analyzing means. Layout processing means for optimally arranging paper so that waste of paper is reduced and generating a cut line indicating a boundary of the arranged plurality of drawings, and the drawing data and the cut line processed by the layout processing means are bitmapped. Bitmap expansion processing means for expanding, frame storage means for storing the drawing data and cut lines expanded into bitmap data by the bitmap expansion processing means, and the drawing data and cut stored in the frame storage means Control means for sequentially reading out the lines and controlling each part, and conveying the recording paper under the control of this control means A thermal recording apparatus comprising: a paper conveying unit; and a thermal head that outputs the drawing data and the cut line to the recording sheet based on the drawing data and the cut line sequentially read from the frame storage unit. FIG. 3 is a diagram illustrating a sheet exchange detection unit that detects that a sheet has been exchanged, and a position that shifts the position of the cut line in the heating resistor array direction of the thermal head each time the recording sheet exchange is detected by the sheet exchange detection unit. And a shift means.

The drawing shift means may shift the positions of both the cut line and the drawing data, or may shift only the position of the cut line. In the former case, the processing can be performed only by shifting the coordinate origin of the entire drawing data including the cut line, and in the latter case, there is an advantage that the amount of data used for the shift processing becomes small. Further, the drawing shift means may shift the storage position of the cut line in the frame storage means, for example, at the time of expanding the bitmap, or the drawing data can be transferred from the frame storage means to the thermal head. Alternatively, the shift amount of the cut line may be controlled.

[0010]

In general, the drawing size is not so strict, and variations of about ± 2 mm are practically acceptable. According to the present invention, for example, the position of the cut line in the direction of arrangement of the heating resistors of the thermal head is shifted within the range of this variation each time the recording paper replacement is detected. For this reason, the position of the cut line shifts every time the recording paper is replaced, and the position of the heating resistor of the thermal head for drawing the cut line also shifts accordingly.

As described above, according to the present invention, the heat generating resistor that draws the cut line in the sheet conveying direction can be changed every time the recording paper is replaced, so that only a specific heat generating resistor can be used as in the conventional case. As compared with the case where a cut line is drawn, the usage time of the heating resistor can be shortened to several tenths to several tenths. Therefore, the life of the thermal head can be significantly extended as compared with the conventional case.

Further, according to the present invention, the timing for shifting the cut line is when the recording paper is replaced.
Usually, when the recording paper is replaced, its set position often deviates slightly from the previous set position. Therefore, even if the cut line is shifted for each recording sheet, it will not be noticeable unless the shift amount is extreme. Moreover, in the present invention, the position of the cut line does not change unless the recording paper is replaced, so that there is no problem due to the shift of the cut line for the drawings of the same lot.

[0013]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a functional block diagram showing the configuration of a thermal plotter according to the first embodiment of the present invention.
Drawing data is, for example, CAD consisting of ASCII coat
CA (not shown) in the form of data (plotter command)
Sent from the D system. This CAD data (plotter command) is stored in the input buffer 1. CAD data (plotter command) stored in input buffer 1
Is supplied to the layout processing unit 3 after being analyzed by the analysis unit 2 and converted into internal (intermediate) data composed of vector data and the drawing size is recognized.

The layout processing unit 3 stores a plurality of storage units 4a, 4b, ..., 4 for storing drawing data for each drawing size.
n, a layout table 5 that stores the rules for the optimum layout, a management unit 6 that sorts the drawing data of each size stored in the storage units 4a to 4n, and determines the output order of the drawing data according to the layout rules. The layout determining unit 7 optimally arranges each drawing in accordance with the output order of the drawing data determined by the management unit 6 and generates a cut line indicating the boundary between them. The layout determining unit 7 also constitutes drawing shifting means for determining the layout position of the drawing data and the cut line based on the reference point P from the reference point changing unit 16 described later.

The drawing data and cut lines optimally arranged by the layout determining unit 7 are D-mapped by the bitmap expansion processing unit 8.
DA (Digital differential analyzer) processing is performed and expanded into bitmap data. The obtained bitmap data is stored in the frame buffer 9.

The bitmap data stored in the frame buffer 9 is sequentially read by the controller 10. The controller 10 controls the paper transport unit 11 to control the transport of the recording paper, and sequentially supplies the drawing data and the cut lines read from the frame buffer 9 to the shift register 12. The shift register 12 sends the supplied drawing data and cut lines to the thermal head 13. The thermal head 13 performs necessary thermal recording or thermal transfer recording on a recording sheet (not shown) according to the drawing data and the cut lines.

On the other hand, the thermal plotter has a storage unit 14 for storing drawing data and cut line arrangement reference points.
And a roll paper replacement detection unit 15 that detects that the roll paper, which is a recording paper, has been replaced, and a reference point stored in the storage unit 14 each time the roll paper replacement detection unit 15 detects replacement of the roll paper. A reference point changing unit 16 that changes For the storage unit 14, a non-volatile memory such as an EEPROM is used. The reference point changed by the reference point changing unit 16 is supplied to the layout determining unit 7 as data for specifying the reference point when the bitmap is developed.

Next, the operation of the thermal plotter according to this embodiment having the above structure will be described. Figure 2
It is a flow chart which shows operation of the plotter. When CAD data (plotter command) is stored in the input buffer 1 and analyzed by the analysis unit 3 and a predetermined amount of drawing files is stored in the storage units 4a to 4n, the flow of FIG. 2 is activated.

First, the management unit 6 sorts the drawing files in order of size (S1), and the layout determining unit 7 determines the optimum layout of the drawings (S2). Next, for example, in the case of outputting a horizontally placed drawing vertically in terms of layout, the drawing is rotated by 90 ° (S3). Then, a cut line is generated according to the drawing arrangement (S4). Next, the reference point P is read from the storage unit 14 (S5), and the offset coordinate values of the drawing data and the cut line are calculated based on this reference point P (S6). When the positions of the drawing data and the cut line are determined in this way, these are expanded into a bit map in the frame buffer 9 (S7), and the drawing is performed under the control of the controller 10 (S8).

By the way, when the roll paper runs out and the roll paper is replaced in the course of such processing, the roll paper replacement detection unit 15 detects this and the reference point update interrupt routine shown in FIG. 3 is executed. To start. That is, the reference point changing unit 16 reads the reference point P from the storage unit 14 (S1
1) The reference point P is counted up (S12). At this time, if the reference point P exceeds the maximum shift amount PL,
P is reset to 0 (S13, S14). The maximum shift amount PL is determined by the allowable width of deviation of the cut line (± 2 mm), the arrangement pitch of the heating resistors of the thermal head 13, the one-time shift pitch, and the like. The updated reference point P is stored in the storage unit 14 (S15). The updating of the reference point P is completed by the processing of FIG.

By executing the above processing, as shown in FIG. 4, the position of the cut line 22 on the recording paper 21 before and after the roll paper replacement is located at the thermal head 13.
It will be slightly shifted by Δx in the line direction. As a result, the heating resistor of the thermal head 13 that draws the cut line 22 in the vertical direction is changed, and the specific heating resistor is prevented from being continuously used.

When the heating resistors are arranged at a pitch of 16 dots / mm, if the cutting line 22 is 0.5 mm, the cutting line 22 is drawn by the heating resistors for 8 dots. If the shift operation is performed by one dot for each roll paper exchange, if the allowable width is set to 2 mm, one cycle of the process is completed by 32 roll paper exchanges. In this case, even the resistor that generates heat for the longest time can be shortened to 1/4 the energization time of the conventional one.

FIG. 5 is a functional block diagram showing the structure of the thermal plotter according to the second embodiment of the present invention. In addition,
5, the same parts as those in FIG. 1 are designated by the same reference numerals, and the description of the overlapping parts will be omitted. In the first embodiment, the shift processing is performed on the drawing data and the cut line immediately before the bitmap expansion, but in the second embodiment, the data shift processing is performed after the bitmap expansion. ..

That is, in general, this type of thermal plotter does not use the entire printable range of the thermal head, but the thermal head has a margin of several dots at both ends. Therefore, in this example,
Each time the roll paper is replaced, the controller 31 inputs the updated reference point P from the reference point changing unit 16 and changes the feed amount of the drawing data and the cut line to the shift register 12 according to the reference point P. As a result, the position of the cut line with respect to the thermal head 13 can be changed for each drawing, so that the same effect as that of the above embodiment can be obtained.

According to this embodiment, since it is not necessary to perform the coordinate changing process of each vector data, the processing time required for the coordinate conversion can be shortened and the process up to the bit map expansion can be made common. There are advantages.

In the above embodiment, the example in which both the cut line and the drawing data are shifted has been described, but only the cut line may be shifted. Further, although the thermal plotter is taken as an example, it goes without saying that the present invention can be applied to other thermal recording devices such as a facsimile device.

[0027]

As described above, according to the present invention, since the position of the heating resistor of the thermal head that draws the cut line is changed every time the recording paper is replaced, the heating resistor that draws the cut line is used. The use time of the body can be shortened to several tenths to several tenths of the conventional time. As a result, it is possible to prevent only a specific heating resistor of the thermal head from being overused, and it is possible to significantly improve the life of the entire thermal head.

[Brief description of drawings]

FIG. 1 is a functional block diagram showing a configuration of a thermal plotter according to a first embodiment of the present invention.

FIG. 2 is a flowchart showing an operation of the plotter.

FIG. 3 is a flowchart showing an interrupt routine at the time of roll paper exchange in the plotter.

FIG. 4 is a diagram for explaining a drawing form by the plotter.

FIG. 5 is a functional block diagram showing a configuration of a thermal plotter according to a second embodiment of the present invention.

FIG. 6 is a diagram for explaining an output form of a conventional thermal plotter having a layout function.

[Description of Reference Signs] 1 ... Input buffer, 2 ... Analysis unit, 3 ... Layout processing unit, 4a to 4n ... Storage unit, 5 ... Layout table, 6
... management unit, 7 ... layout determination unit, 8 ... bitmap expansion processing unit, 9 ... frame buffer, 10, 31 ... controller, 11 ... paper transport unit, 12 ... shift register, 1
3, 43 ... Thermal head, 14 ... Storage unit, 15 ... Roll paper replacement detection unit, 16 ... Reference point changing unit, 21, 41 ... Recording paper, 22, 42 ... Cut line.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location B43L 13/00 J 7318-2C

Claims (5)

[Claims] 1. An analyzing unit for analyzing drawing data to recognize a drawing size, and optimally arranging a plurality of drawings on the basis of the drawing size recognized by the analyzing unit so as to reduce waste of recording paper. Layout processing means for generating cut lines indicating boundaries of a plurality of arranged drawings, bitmap expansion processing means for expanding the drawing data and cut lines processed by the layout processing means into bitmaps, and bitmap expansion Frame storage means for storing the drawing data and cut lines expanded into bitmap data by the processing means, and control means for sequentially reading out the drawing data and cut lines stored in the frame storage means and controlling each part, A paper transport means for transporting the recording paper under the control of this control means and a sequential reading from the frame storage means. In a thermal recording apparatus comprising a thermal head that outputs the drawing data and the cut line to the recording paper based on the drawing data and the cut line that are output, a paper exchange detection that detects that the recording paper has been replaced And a drawing shift means for shifting the position of the cut line in the direction of arrangement of the heating resistors of the thermal head each time the replacement of the recording paper is detected by the paper replacement detection means. Recording device. 2. The thermal recording apparatus according to claim 1, wherein the drawing shift means shifts the positions of the drawing data and the cut line. 3. The thermal recording apparatus according to claim 1, wherein the drawing shift means shifts only the position of the cut line. 4. The thermal recording apparatus according to claim 1, wherein the drawing shift means shifts a storage position of the cut line in the frame storage means. 5. The drawing shift means is provided inside the control means, and controls the shift amount of the drawing data and the cut line transferred from the frame storage means to the thermal head. The thermal recording device according to claim 1, wherein