JPS6113993B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a printing ribbon feeding rate control method in a serial impact printer, and in particular, to changing the feeding rate of a printing ribbon (hereinafter abbreviated as ribbon) in accordance with the width of printed characters. This provides a control method that allows efficient use of expensive carbon film ribbons and the like and reduces the frequency of ribbon replacement.

Conventionally, in serial impact printers, the type is selected using a printing character code such as an ASCII code or JIS code, and the type is printed by pressing the type provided on a rotating wheel or cylinder onto paper via a ribbon. In the past, the ribbon feed amount was always determined to be a constant length for each print, regardless of the type of type printed. For example, when using a ribbon such as a carbon film ribbon that cannot be used again once it has been used for printing, the ribbon should be fed according to the maximum width of the type, regardless of the width of the printed type. was being carried out. Therefore, there are disadvantages in that the efficiency of using the ribbon decreases and the frequency of ribbon replacement increases.

Therefore, in order to solve these difficulties, the present invention includes a type holding means such as a rotary wheel or a rotary cylinder having type, an electric drive means for feeding the ribbon, and a method for controlling the position of each character on the type holding means. A character position data storage means for storing data, a ribbon feeding data storage means for storing data regarding ribbon feeding according to characters, and a ribbon feeding data storage means provided between the ribbon feeding data storage means and the electric drive means for feeding the ribbon. The ribbon feeding amount is electrically variably controlled by controlling the electric drive means for feeding the ribbon by the counting means.

In a serial impact printer that uses a rotary wheel or a rotary cylinder holding type as a type holding means, the position of the type can be selected by inputting a print character code in the form of an ASCII code, for example, in a fixed storage device, e.g.
Reads the position address code indicating the location of the type on the type wheel from ROM (read-only memory), counts up or down the contents of the counter for each character pitch on the wheel, and outputs the counter. The current position code of the type wheel is used as the current position code of the type wheel, the position address code read from the ROM is compared with the current position code of the type wheel, and the rotation of the type wheel is controlled until the two match to select the type. Are known. The method for selecting the position of such typefaces is
Since this is not a direct object of the present invention, a detailed explanation of conventionally known methods will be omitted.

Next, the printer of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows three examples of characters with different print widths. For example, the print widths of the uppercase letter "A," the uppercase letter "I," and the lowercase letter "b" are represented by 2x, 2y, and 2z, respectively.

When printing characters with different widths, the ribbon can be used efficiently by controlling the ribbon feed amount using a corresponding feed amount designation code.

FIG. 2 is a block diagram showing an embodiment of the printer of the present invention, FIG. 3 is a time chart thereof, and FIG.
The figure is an example of a ROM code table. In Figure 2, 1 is a 7-bit buffer, 2 is a 256 x 8-bit ROM, 3 is a rotating wheel motor control circuit,
4 is a rotary wheel motor, 5 is a print sequence control circuit, 6 is a ribbon feed control circuit, 7 is a step motor for ribbon feed, and L1 is an ASII
Input line for code printing character code, L2 is input line for print start command, L3 is output line for buffer 2, L4 is input/output line for ribbon feed start command, L5 is input/output line for ROM switching command, L
6 is an input/output line for the ribbon feed control signal, L7 is an input/output line for the rotating wheel motor control signal, L9 is an input/output line for the buffer-in command, L10 is an input/output line for the wheel rotation end signal, and L11 is an input/output line for the wheel rotation end signal.
7 output input/output line, L12 is also ROM2 1
〜4 output input/output lines, L13 indicates the input/output line of the ribbon feeding end signal, and L1〜 in FIG.
L7 is the signal waveform of the corresponding coded part in FIG.
8 is the signal waveform of the hammer command.

In this case, the ribbon is fed twice for one printing, half before printing and the other half after printing. The ribbon feed amount designation code is made up of, for example, a 4-bit binary number, so that 16 states from 0 to 15 can be output, and 1 state corresponds to 1 step of the step motor 7 that drives the ribbon feed mechanism. We are beginning to respond. In the case of FIG. 1, for example, x is 12, y is 5, and z is 9, which are determined corresponding to each printed character code. In addition, in the case of Alphabet, the printed character code and position address code require the use of 26 uppercase and lowercase letters, numbers 0 to 9, and other symbols, so up to 128 types of codes are possible.
It consists of 7 bits of base number.

While the print character code in ASCII code is being input to the 7-bit buffer 1 from the input line L1, a print start command pulse is applied from the input line L2 to the print sequence control circuit 5, and a buffer in command is generated from the control circuit 5. controls the 7-bit buffer 1 through the input/output line L9,
The inputted print character code is stored in buffer 1. The buffer 1 also provides a print character code to the ROM 2 through the input/output line L3.

This ROM2 has a storage capacity of 256 x 8 bits, and uses two addresses for each of up to 128 possible print character codes, and a 7-bit position address code and its A 4-bit ribbon feed amount designation code corresponding to the type width is stored. FIG. 3 is an example of a ROM code table, in which one bit out of eight bits is used to switch between a position address code and a ribbon feed amount designation code.

From ROM2, from the address specified by the input 7-bit print character code,
First, the ribbon feed amount specification code is read. In this case, the ROM switching command given from the print sequence control circuit 5 through the input/output line L5 becomes a logic "0" state, and the ROM switching command as shown in FIG.
The bit ribbon feed amount specification code is sent from the specified address to the input/output line L as ribbon feed data.
12, the data is stored in a 4-bit counter provided in the ribbon feed control circuit 6.

Next, when a ribbon start command is given from the print sequence control circuit 5 to the ribbon feeding control circuit 6 through the input/output line L4, the control circuit 6 rotates the ribbon feeding step motor 7 through the input/output line L6. Ribbon feed data stored in a 4-bit counter is used for this rotation control, and the contents of the counter are decremented one by one as the step motor rotates one step, and when the contents reach "0", the step motor 7 is Rotation is stopped.

In this way, the ribbon feeding control before printing is completed. When the ribbon feeding is completed, a ribbon feeding end signal is given from the control circuit 6 to the print sequence control circuit 5 via the input/output line L13.

On the other hand, after the ribbon feed data is stored in the counter in the control circuit 6, the print sequence control circuit 5 changes the ROM switching command to a logic "1" state and changes the input address of the ROM2 through the input/output line L5. , reads out the position address code corresponding to the inputted print character code.

The position address code is composed of 7 bits, and outputs 1 to 4 are given to the rotating wheel motor control circuit 3 from the output line L12, and outputs 5 to 7 are given from the output line L11. This position address code is given to the rotating wheel motor control circuit 3 as target position address data, and the control circuit 3 is provided with a counter for indicating the current position of the wheel, which holds the current position address code. .

The input target position address data is then compared with the contents of a counter indicating the current position address, and the rotary wheel motor 4 is rotated in the forward or reverse direction depending on the comparison result. That is, the contents of the counter in the control circuit 3 are counted up or down for each character pitch, and the motor 4 is rotated through the input/output line L7 until the target position address and the current position address match, and then the motor 4 is rotated through the input/output line L7 until the target position address and the current position address match. Sometimes it stops rotating.
At the same time, the control circuit 3 provides a motor rotation end signal to the print sequence control circuit 5 through the input/output line L10.

When the control circuit 5 receives the ribbon feeding end signal from the input/output line L13 and the motor rotation end signal from the input/output line L10, it changes the ROM switching command to the logic "0" state again, and outputs the signal through the input/output line L5.
The address of the ROM 2 is changed so that the ribbon feed amount designation code after printing can be read out, and a hammer command for operating the hammer is generated (not shown).

After the hammer operation is completed, as before printing,
Ribbon feed data is applied from the ROM 2 to the ribbon feed control circuit 6 via the L12, and the step motor 7 is operated to feed the ribbon after printing. When the ribbon feeding is completed, the control circuit 6 connects the input/output line L.
A ribbon feeding end signal is given to the print sequence control circuit 5 via the printer 13, and one printing cycle is completed.

In this way, in response to the input printing character code, the position address code of the type and the ribbon feed amount designation code are read from the ROM 2, and the ribbon feed amount is controlled in proportion to the width of the type to be printed. For example, the printing ribbon can be used efficiently.

In addition, in the explanation of Figures 2 to 4, the ROM
This example shows a method of using 7 bits of a character code printed in ASCII code and 1 bit of a ROM switching instruction as input for 2, but this method uses a standard ROM (256 x 8 bits) available on the market. It is also possible to configure the ROM 2 with two pieces, one for the position address code and the other for the ribbon feed amount designation code. In this case, 128 x 7 bits and 128
It is sufficient that a storage capacity of ×4 bits can be obtained. In addition, the input printing character code should be used only to output the position address code, and a signal re-encoded from the current or target position address code should be used to specify the address for the ribbon feed amount specification code. You can also do it.

Furthermore, although this explanation has given an example of a control method in which the ribbon is fed by an amount corresponding to half the type width before and after the hammer operation, the printer of the present invention is limited to such a control method. It's not something you can do.

For example, after printing a certain character, first feed the ribbon by an amount corresponding to the maximum type width,
When the next character code to be printed is input, the ribbon may be fed backwards in accordance with the character width. In such a control system, the ribbon feed amount designation code is given by the difference from the maximum type width. Even with this control method, the ribbon feed amount specification code can determine a unique feed amount for each print character code, so as in the case described above, the ribbon feed amount specification code can be used to determine the next print When the desired printing character code is input, the ribbon can be fed as necessary for printing.

On the other hand, a control method in which the ribbon is fed only once for each print is also possible. In this control method, it is necessary to determine the ribbon feed amount by adding the width of the type that was previously printed and the width of the type that is to be printed next. In that case, the ribbon feed data read from the ROM 2 using the previously printed character code is stored in a counter in the ribbon feed control circuit 6, for example, and then read using the input character code. Addition is made to the issued ribbon feed data. In this way, ribbon feeding can be completed in one operation.

As described in detail above, the printer of the present invention uses a ribbon for printing, and includes a printing means for printing characters, an electric drive means for feeding the ribbon, and a printer for each character for printing. character data storage means for storing data;
Ribbon feeding data storage means for storing data regarding ribbon feeding according to characters, and counting means provided between the ribbon feeding data storage means and the electric driving means, and the counting means causes the electric driving means to By controlling , the amount of ribbon feed is electrically variably controlled.

That is, as explained in connection with FIGS. 2 to 4, data on the ribbon feed amount is stored.
ROM and other memories, a counter provided in the ribbon feed control circuit that stores data from this memory, and the contents set in this counter allow variable feeding of the ribbon by an electric drive means such as a step motor. This is what we do.

Further, the character data storage means and the ribbon feed data storage means may be the same storage means, and each data may be sequentially outputted from the storage means.

With the configuration described in detail above, the printer of the present invention makes it possible to feed the minimum amount of ribbon necessary for actual printing in accordance with each character width, and particularly improves the efficiency of using expensive printing ribbon. It can be significantly improved, and the effect is extremely large.

[Brief explanation of the drawing]

Fig. 1 shows three examples of characters with different print widths, Fig. 2 is a block diagram showing an embodiment of the printer of this invention, Fig. 3 is its time chart, and Fig. 4 is
This is an example of a ROM code table. In the drawing, 1 is a 7-bit buffer, and 2 is a 7-bit buffer.
ROM, 3 is a motor control circuit for rotating wheels, 4
5 is a rotating wheel motor, 5 is a print sequence control circuit, 6 is a ribbon feed control circuit, and 7 is a ribbon feed step motor.

Claims (1)

[Scope of Claims] 1. In a printer using a ribbon for printing, a type holding means such as a rotating wheel or a rotating cylinder having type, an electric drive means for feeding the ribbon, and a type holding means for each character. a character position data storage means for storing data regarding the position of the character, a ribbon feed data storage means for storing data regarding the ribbon feed according to the character, and an electric drive means for feeding the ribbon with the ribbon feed data storage means. and a counting means provided between the
A printer characterized in that the amount of ribbon feeding is variably controlled electrically by controlling the electric drive means for feeding the ribbon by the counting means. 2. The printer according to claim 1, characterized in that the character position data storage means and the ribbon feed data storage means are the same storage means, and each data is sequentially output from the storage means. printer.