JPH01184157A - printing device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a raster scan type printing device that outputs characters or images as a set of dots, and particularly relates to a raster scan type printing device that outputs characters or images as a set of dots. The present invention relates to a printing device that allows for the shortest time possible.

[Conventional technology]

In a printing device such as a laser printer in which the printing process speed is fixed, the printing speed is faster when the paper is fed horizontally. FIG. 4 shows an example of a document written horizontally on vertically long paper, where (a) shows the case where the paper is fed vertically, and (b) shows the case where the paper is fed horizontally, and F indicates the feeding direction of the paper.

Here, assuming that the maximum paper width of the printing device is A3, if the paper used is A4 or smaller, the paper shown in FIG. 4(a).

Both printing methods in (b) are possible, but the paper used is A.
3, only the printing direction (a) can be taken.

Therefore, the character information for printing needs to have vertical information as shown in FIG. 5(,). Furthermore, if you try to improve the printing speed of the printing device by printing in the direction shown in Fig. 4(b) using paper of A4 or smaller, the printing speed shown in Fig. 5(b)
Horizontal text information as shown in is also required.

The methods that have been mainly used in the past as means for obtaining the two types of character information shown in FIGS. 5(a) and 5(b) can be roughly divided into the following two types. Namely.

(1) Two types of information, vertical and horizontal, are stored for the same character.

(2) Only one of vertical and horizontal character information is stored, and the other character information is generated by vertical and horizontal conversion when necessary.

As a specific example of (2), LS of vertical and horizontal conversion! (for example,
Advanced Micro Devices Co., Ltd., Japanese version technical data, Am 95C760RP).

[Problem to be solved by the invention]

However, in the above-mentioned conventional technology, there is a drawback that (1) requires the storage capacity of character information twice the number of characters, and as for (2), it takes a long time to execute vertical/horizontal conversion using software. There was a problem in that in order to increase the speed, hardware having a function of vertical/horizontal conversion was required.

SUMMARY OF THE INVENTION An object of the present invention is to provide a printing device that has only the minimum necessary character information and can perform high-speed printing without requiring hardware for vertical/horizontal conversion.

[Means to solve the problem]

The purpose of the above 4 is to calculate the sum of print data creation time and printing time from the print format and number of print sheets when printing a document.
This can be achieved by providing a printing apparatus that calculates the case where the paper is fed vertically and the case where the paper is fed horizontally, and selects the shorter of the above sum values.

[Effect]

The length in the paper feeding direction is LP, and the paper interval during continuous printing is L.
If B is the paper feed speed and V is the printing time per sheet of paper, then the printing time T per sheet is expressed by the following equation.

Tm (Lp+Lu)/v ・=(
1) Also, let To be the time required to create the print data, and TLS be the lost time until the printing of the first sheet is completed.

The time Tm actually required to print m sheets of paper is expressed by the following equation.

T m = To + T X m + T +, s
・=(2) Furthermore, the time per character required for vertical/horizontal conversion of character information is Tr, and the number of characters in one document is Nc.
h, then the print data creation time To (a), TD (b) in Fig. 4 (a), (b) is the following relational expression % formula % (1), (2), (3) From the relationship of the equations, the times Tm(a) and Tm(b) required to print m sheets using methods (a) and (b) in FIG. 4 are 1, respectively, and Tm(a)=To+(Lp(a) )+LB)/v−m+
TLs...(4)Tm(b
)=Tn+TrXNch+(Lp(b)+LB)/s
−m+Tt,s ・=(5), therefore, Tm (a)−T m (b)=(Lp(a)−LB
(b))/v-m-TrX Ncb-(6) holds true.

As described above, for documents to be printed, before creating print data, the paper size, print format, number of characters, and number of required sheets can be determined (
The optimum printing direction can be determined by calculating the values of Lp(a), LB(b), Nch, m, etc. in equation 6).

〔Example〕

Hereinafter, the content of the present invention will be explained in more detail with reference to Examples.

The printing apparatus of this embodiment is composed of a laser printer that combines an electrophotographic process and a laser scanning system, and a printer controller that creates raster data to be applied to the laser scanning system.
It has an automatic paper feeding mechanism with two paper cassettes, and the selection of paper cassettes is controlled by the printer controller.

Figure 1 shows a block diagram of the printer controller, including a central processing unit (CPU) 1 that performs overall management and drawing processing, and a computer graphics read-only memory (CGROM) that stores information in units of character dots.
) 2, program memory for CPUI 3, host (
A host interface (host I/F) 4 that exchanges signals with a computer (not shown), a batch message program memory (BMP memory) 6 for developing print data, and converts the Plallel data in the BMP memory 6 into serial data for the laser printer. P/S converter 7, CPU 1 and P/S
A time division control unit 5 controls the accesses of the conversion unit 7 to the BMP memory 6 so as not to collide, and an LP interface (LPi/ F) Indicates that it consists of 8.

Here, the CPUI reads the character information from the CGROM2 in accordance with the print information given via the host i/F4.
Transfer the data to the MP memory 6 to create print image data on the memory, and transfer the data to the BMP memory 6-
/S converter 7 converts the data into serial data and outputs it to a laser printer.

In addition, here, the CGROM 2 stores only vertical character patterns, and a schematic example thereof is shown in FIG. 5(a).
Shown below.

Further, FIG. 4(a) shows a standard printing form in the printing apparatus of this embodiment, where F indicates the paper feeding direction, S indicates the raster scan direction, and O indicates the origin position when printing data is developed. . In the case of a laser printer, the printer's printing time is determined by the length of the paper in the printing direction, so
The printing time of the printer in FIG. 4(b) is shorter than that in FIG. 4(a). In the laser printer of this example,
When using A4 paper, the processing capacity is 12 sheets/minute in FIG. 4(a) and 15 sheets/minute in FIG. 4(b).

Figure 3 shows the relationship between Tm(a) and Tm(b) and the number of printed sheets m when the number of characters Nch is fixed and printed using equations (4) and (5). , the number of printed sheets m is the point where the two straight lines intersect, that is, (b)
If the number of sheets corresponding to the point where the value of the formula becomes zero is less than the number
It can be determined that this method is more advantageous. Depending on this result, a cassette selection signal may be issued from the L P i /F 8 to select a necessary cassette.

FIG. 2 shows a flowchart of paper feeding direction selection.

In other words, ■ From the print format in the document data, if the paper is to be fed horizontally, it is determined whether vertical/horizontal conversion of character data is necessary; ■ If vertical/horizontal conversion is not necessary, the print data for horizontal feeding is , and perform horizontal feed printing.

■If vertical/horizontal conversion is required, the printing time Tm (
Calculate a) and the printing time Tm (b) required for horizontal feed printing, and (2) compare Tm(a) and Tm(b).

■When horizontal feed printing takes less time (Tm(a)
>Tm In (b)), while converting the character data vertically and horizontally, print data for horizontal printing is created, and (1) horizontal printing is performed.

■If the time required for horizontal printing is longer (Tm(a)
<Tm (b)) Create print data for vertical printing, and perform vertical printing.

In addition, in the case of Tm (a) = Tm (b), when horizontal printing is performed, the print data creation time To becomes longer due to the time required for vertical/horizontal conversion, and the time until the printing of the first page is completed also becomes longer. Therefore, print vertically.

〔Effect of the invention〕

As mentioned above, in a raster scan type printing device that outputs characters or images as a set of dots,
In other words, the printing apparatus configured according to the present invention calculates the sum of development time and printing time based on the printing format and the number of sheets to be printed, for when the paper is fed vertically and when the paper is fed horizontally, and the required time is calculated. By creating a printing device that makes it possible to select the shorter one, the drawbacks seen in the prior art are overcome, and it only has character information in a single direction, and does not require hardware for vertical/horizontal conversion. It was possible to provide a printing device that can minimize the time required for printing without having to do so.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a printer controller of an embodiment of the printing apparatus of the present invention, FIG. 2 is a flow chart 1 to 1 showing the procedure of printing direction selection processing, and FIG. FIG. 4 is an explanatory diagram of the printing method, and FIG. 5 is a diagram showing the dot decomposition of character information. 1...CPU, 2...CGROM, 3...Program memory, 4...Host I/F, 5...Time division control unit, 6...BMP memory, 7...P/ S conversion unit, 8...LPi/F.

Claims (1)

[Claims] 1. In a raster scan type printing device that outputs characters or images as a set of dots, the printing time is determined by the paper size in the paper feed direction, and the paper direction during printing can be selected between portrait and landscape. Based on the number of sheets to be printed, the sum of the print data creation time and printing time is calculated for when the paper is fed vertically and when the paper is fed horizontally, and it is possible to select the smaller of the above sum values. A printing device characterized by: