JPS62242570A - Ribbon feeder - Google Patents

Abstract

PURPOSE:To constantly prevent a ribbon from sagging and print clearly, by providing a controlling means which drives a ribbon-feeding motor by a one- character amount each time an operation of a printing part is finished, and drives the ribbon-feeding motor for a predetermined period of time each time a carrier-returning operation is finished. CONSTITUTION:When data designates a carrier return, a carrier return code is received through an interface 11, a common signal COM (a) for a carrier motor driving circuit 19 is kept at an L level for a period of time T0, exciting signals for phases A, B, A<->, B<-> of a carrier motor 18 are switched, and the motor 18 is rotated, thereby returning a carrier leftward to a home position. In the next period T1, a common signal COM (f) for a ribbon-feeding motor driving circuit 23 is kept at an L level, exciting signals for phases A, B, A<->, B<-> of a ribbon-feeding motor 22 are switched by a two-phase amount, and a take-up shaft 7 is driven to feed a ribbon leftward by 1/2 or 1/4 times a one-character amount, thereby stretching the ribbon 8 tight. Immediately thereafter, a solenoid driving circuit 15 drives a solenoid 14, and a printing hammer is caused to strike the back face of a type part of a print wheel, thereby printing a character.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention This invention relates to a ribbon feeding device for use in printing machines.

Conventional technology In a printing machine in which a printing unit, a ribbon, and a ribbon feed motor are mounted on a carrier, each time a character is printed, the carrier motor is driven to move the carrier by one character, and the ribbon feed motor is driven to move the ribbon. The carrier motor is driven to return the carrier to the home position each time the carrier is fed by one character and each line is printed.

Problems to be Solved by the Invention However, in order to reduce the driving force for feeding the ribbon, it is not possible to apply a large amount of tension to the ribbon. There is a problem that the ribbon becomes loose and the print marks in front of the ribbon overlap during each printing operation, making the print unclear.

The second invention was made in view of these points, and aims to provide a ribbon feeding device that can always prevent the ribbon from becoming slack and can perform clear printing.

Means for Solving the Problems A control section is provided which drives the ribbon feed motor for one character each time one operation of the printing section is completed, and drives the ribbon feed motor for a certain period of time each time the return operation of the carrier is completed.

Therefore, no matter what purpose the carrier is moved, the ribbon is always fed to prevent the ribbon from becoming loose.

Example An embodiment of the present invention will be described based on the drawings.

As shown in FIG. 2, a carrier 3 is slidably fitted onto a carrier shaft 2 parallel to the platen 1. As shown in FIG. This carrier 3 is printed with a print wheel 4 and a printing hammer 5! ) IS6 is mounted, and a cassette case 9 having a ribbon winding shaft 7 and storing a ribbon 8 is detachably attached thereto.

Next, FIG. 1 shows a control circuit. CPU which is the control unit
10 includes an interface 11, a ROM 12 in which a program is written, a RAM 13, and a solenoid 14.
Solenoid drive circuit 15 that drives the paper feed motor 1
6, a carrier motor drive circuit 19 that drives the carrier motor 18, a print wheel motor drive circuit 21 that drives the print wheel motor 20, and a ribbon feed motor that drives the ribbon feed motor 22. A drive circuit 23 and a clock signal generation circuit 24 are connected. The solenoid 14 is fixed to the carrier 3, and its movable core is in contact with the back surface of the printing hammer 5. A paper feed motor 16 is connected to the platen l. The carrier motor 18 is the carrier shaft 2
The carrier 3 is connected to one of pulleys (not shown) disposed near both ends of the carrier 3, and a portion of the wire wound around these pulleys is fixed to the carrier 3. The print wheel motor 20 is mounted on the carrier 3 and connected to the print wheel 4. The ribbon feed motor 22 is mounted on the carrier 3 and connected to the ribbon take-up shaft 7.

In such a configuration, first, the moving operation of the carrier 3, the ribbon feeding operation, and the printing operation will be described with reference to the timing chart of FIG.

If the data is a carrier return, the return code of the carrier 3 is received and received by the interface 11, the common signal COM of the carrier motor drive circuit 19 is set to the T0 time level, and the excitation signal of each phase of ABAB of the carrier motor 18 is switched. , the carrier motor 18 is rotated to return the carrier 3 to the left home position.

At the next time T1, the common signal COMti of the ribbon feed motor drive circuit 23 is set to L level, and the excitation signal of each phase of ABAB of the ribbon feed motor 22 is switched for two excitation phases.
Drive the take-up shaft 7 to move the ribbon 8 leftward by half the length of one character.
The slack in the feed ribbon 8 is removed by a feed amount of 1/4 to 1/4. Immediately after this, the solenoid drive circuit 15 drives the solenoid 14, and the print hammer 5 drives the print wheel 5.
Tap the back of the type part to type one character.

During the next 13 hours, the common signal COM of the carrier motor drive circuit 19 is set to L level, and the A of the carrier motor 18 is
Switch the excitation signal of each phase of Bx100, carrier motor 18
Rotate and move carrier 3 one character to the right. Although not shown in the timing chart, during these 18 hours, the print wheel motor 20 is driven to rotate the print wheel 5 and the next printed character section is opposed to the print hammer 5.

At the next time T1, the common signal COM of the ribbon feed motor drive circuit 23 is set to L level, and the ribbon feed motor 22
The excitation signal for each phase of ABλ100 is switched by 4 to 8 excitation phases, and the take-up shaft 7 is driven to send the ribbon 8 to the left with a feed amount equivalent to one character. Immediately after this, the solenoid 14 is driven and the printing hammer 5 prints.

Next, the flow of operations for printing, carrier movement, ribbon feeding, and carrier return will be explained with reference to the flowchart in FIG. The operations of circuit parts and mechanical parts are redundant and will therefore be omitted. First, when you turn on the power, initial processing is performed.
If there is data and it is determined that the data is a printed character, the ■ character part is printed and the carrier 3 moves 1 in the printing direction to the right.
The ribbon 8 is fed by one character. If the data is determined to be a carrier return, the ribbon 8 is sent for two excitation phases. If the data is neither a printed character nor a carrier return, other processing (for example, paper feeding by driving the paper feeding motor 16) is performed.

In this way, when the carrier 3 is moved, the ribbon can be constantly fed, so that the ribbon 8 can be prevented from becoming loose and clear printing can be performed.

Effects of the Invention Since the present invention is configured as described above, it is possible to prevent the ribbon from becoming loose even when the carrier is moved in the printing direction and even when it is returned to the home position. This has the effect that clear printing can be performed using the unused portion of the ribbon.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention; FIG. 1 is a circuit diagram, FIG. 2 is a plan view, FIG. 3 is a timing chart, and FIG. 4 is a flow chart. 3...Carrier, 6...Printing section, 8...Ribbon,
■. ...CPU (control unit), 18...Carrier motor, 22...Ribbon feed motor

Claims (1)

[Claims] A carrier on which at least a printing section, a ribbon, and a ribbon feed motor are mounted is connected to the carrier motor so as to be movable back and forth, and each time one operation of the printing section is completed, the ribbon feed motor is driven by one character, and the A ribbon feeding device comprising: a control section that drives the ribbon feeding motor for a predetermined period of time each time a carrier return operation is completed.