JPH0215396B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a small printer that has both a paper feed mechanism and a multicolor ink ribbon mechanism, and the electromagnets used for the paper feed mechanism and the multicolor ink ribbon mechanism are unified into one. related to technology.

Generally, small printers are equipped with a paper feeding mechanism that feeds a fixed amount of printing paper, and a multicolor ink ribbon mechanism that uses multicolor ink ribbons to use different printing colors. In particular, paper feeding mechanisms include normal paper feeding, which feeds a fixed amount of printed paper after printing, and fast feeding, which feeds a large amount of printed paper in a short period of time. Both the paper feed mechanism and the multicolor ink ribbon mechanism use electromagnets, which are used to switch between normal paper feed and rapid feed in the case of the paper feed mechanism, and to switch between printing colors in the case of the multicolor ink ribbon mechanism. This is what has become the norm. A conventional paper feeding mechanism including a rapid feeding mechanism for printing paper is typified by Japanese Patent Application Laid-Open No. 121405/1983, and a multicolor ink ribbon device is typified by Japanese Patent Application Laid-open No. 50-97511. A timing chart of a small printer equipped with this paper feeding mechanism and multicolor ink ribbon mechanism will be described with reference to FIG. This printer consists of a type wheel selection process, a printing process, and a type wheel reset process.The type wheel selection process is a process in which a predetermined type on each independent type wheel is selectively locked in the printing position. It generates timing pulses that are synchronized with movement.
The printing process is a process in which the type selected and locked in the type wheel selection process is pressed with a platen to print characters on printing paper.At this time, an ink ribbon is used as a medium for printing characters on the printing paper, and the platen and The color of the ink ribbon corresponding to the selectively locked type appears as the color of the printed character, so the color of the ink ribbon must be changed before the printing process. The type wheel reset process is
This is a process in which the selectively locked and printed type wheel is returned to its original standby state, and normal paper feeding is also performed during this period. In the following, we will explain how to rapidly advance the paper and change the ribbon color during these movements. First, the paper is rapidly fed. In this case, no printing is performed, and the paper is fed three times during one print cycle time. This means that if you energize the electromagnet for fast paper feed shown in Figure 3 from timing pulse 0 to 4, the first paper feed, second paper feed, and third paper feed (same as normal paper feed) is accomplished. The movement of the mechanism is based on JP-A-Sho.
According to 52-121405.

Next, ribbon color switching will be explained. When the ribbon color switching electromagnet is energized from timing pulses 4 to 8, the member holding the ink ribbon shifts in the vertical direction at section a in FIG. 1, and the color of the ink ribbon at the position facing the platen changes. The movement of the mechanism is based on Utility Model No. 50-97511.

The small printers described so far require two expensive parts: an electromagnet for rapid paper feeding and an electromagnet for ribbon switching, resulting in high costs. Furthermore, in order to drive this electromagnet, a drive transistor or a spark killer diode is required in the electronic circuit, but these also have the disadvantage of requiring two of each, making them increasingly expensive.

The present invention eliminates such drawbacks, and aims to provide an inexpensive small-sized printer by using a single electromagnet for fast-forwarding paper and an electromagnet for switching ink ribbon.

The small printer according to the present invention includes a paper feed roller, a paper presser roller that presses the paper feed roller through the printing paper, a paper feed pawl wheel that is coaxially attached to the paper feed roller, and a paper feed roller that oscillates about the shaft. A paper feed lever that rotates dynamically, a paper feed cam that engages with the paper feed lever to swing and rotate the paper feed lever and rotates a paper feed claw wheel intermittently, and a paper feed cam that engages with the paper feed lever to rotate the paper feed lever intermittently. A paper feed control lever that locks, a ribbon frame that guides the multicolor ink ribbon to the printing position, a spring member that biases the ribbon frame in one direction, and a multicolor ink ribbon that engages with the ribbon frame in stages. A ribbon position switching lever that selectively switches the color of the ink to the printing position, an ink ribbon reset cam that engages with the ribbon frame and returns the ribbon frame to its initial position, and a paper feed control lever and ribbon position switching lever that are sucked and shaken. The paper feed cam locks the paper feed lever and the color of the multicolor ink ribbon is changed.
The ink ribbon reset cam is characterized in that it is performed at the second timing when the ink ribbon reset cam locks the movement of the ribbon frame and the paper feed operation is performed.

FIG. 2 shows a specific example of a small printer according to the present invention and will be described.

Reference numeral 1 denotes a type wheel with type 101 provided on its outer periphery; 2 a platen that presses the type 101 via a printing paper 3 and an ink ribbon 4 to print on the printing paper 3; and 5 an ink ribbon frame that guides the ink ribbon 4. , the arrow b is always centered around 501 due to the spring 6.
trying to rotate in the direction. 7 rotates the ink ribbon frame 5 in the direction of arrow b to the first position 7.
This is a ribbon position switching lever that locks at the first position 701 or the second position 702, and when it locks at the first position 701, the ink ribbon 401 of the first color is set at the printing position (position facing the platen), and the ink ribbon 401 of the first color is If the ink ribbon 4 of the second color is locked at the position 702 of
02 is set. 8 is an ink ribbon reset cam fixed to a shaft 9 that rotates once per printing cycle, and is a part 502 of the ink ribbon frame 5.
The second color ink ribbon 402 has a function of returning to its original position after being set at the printing position. 11 is a paper feed roller, and paper feed roller shaft 1
It is fixed at 2. Reference numeral 13 denotes a paper press roller which pinches the printing paper 3 and presses the paper feed roller 11. A paper feed ratchet wheel 14 is fixed to the paper feed roller shaft 12. A paper feed claw 15 engages with the paper feed ratchet wheel and rotates the paper feed roller 11 intermittently, and is rotatably attached to the paper feed lever 16. A paper feed cam 17 is fixed to the shaft 9, and cooperates with a spring 19 to swing the paper feed lever 16. 18 is a paper feed control lever that controls the swinging of the paper feed lever 16. Reference numeral 10 is an electromagnet that can attract both the paper feed control lever 18 and the ribbon position switching lever 7. The operation of the small-sized printer having such a configuration will now be described with reference to the timing chart shown in FIG. This printer consists of a type wheel selection process, a printing process, and a type wheel reset process. A timing pulse synchronized with the movement of 1 is generated. The printing process is a process in which the type selected and locked in the type wheel selection process is pressed by the platen 2 to print characters on the printing paper 3. At this time, the ink ribbon 4 is used as a medium for printing the characters on the printing paper 3. Yes, the color of the ink ribbon corresponding to the platen 2 and selectively locked type appears as the color of the printed character, so the color of the ink ribbon must have been changed before the printing process. Must be. The type wheel reset process is a process in which the selectively locked and printed type wheel 1 is returned to its original standby state, and normal paper feeding is also performed during this period. Next, we will explain how to change the ribbon color and rapidly feed the paper during these movements. First, in ribbon color switching, the electromagnet 10 is energized from timing pulses 0 to 4 during the type wheel selection process. Part 502 of the ink ribbon frame 5 is engaged with the outer circumferential part 801 of the ink ribbon reset cam 8 until halfway through the energization, and there is a gap c between the ribbon position switching lever 7 and the ink ribbon frame 5, so the ribbon position cannot be changed. The lever 7 is easily attracted by the electromagnet 10 in the direction of arrow d. In this state, the ink ribbon reset cam 8 rotates in the direction of the arrow e, and the outer peripheral part 801 and the part 5 of the ink ribbon frame 5
Ink ribbon frame 5 due to disengagement with 02
is rotated in the direction of arrow b by the spring 6 and is locked at the second position 702 of the ribbon position switching lever 7, and the ink ribbon 402 of the second color faces the printing position, completing the ribbon color switching. (Part g in Figure 3)
If the platen 2 presses the type 101 in this state, the type will appear in the second color. During the type wheel reset process, the ink ribbon reset cam 8 comes around again and a part 502 of the ink ribbon frame 5 is removed.
Press to return to the state shown in FIG. Furthermore, electromagnet 10
If the timing pulses 0 to 4 are energized, the paper feed control lever 18 is also attracted in the direction of arrow f and disengages from the paper feed lever 16. However, during the timing pulses 0 to 4, the paper feed control lever 16 does not hold the paper. Since the paper feed lever 16 is engaged with the cam portion 171 of the feed cam 17, the paper feed lever 16 does not swing. Therefore, paper is not fed either. Next, fast forwarding of paper will be explained. In this case, printing is not performed and the paper is fed three times during one printing cycle time. The electromagnet 10 that was energized during the previous ribbon color switching is now energized from timing pulses 4 to 8. (Dotted line in FIG. 3) The paper feed control lever 18 is attracted in the direction of arrow f. During this suction, the paper feed cam 17 rotates in the direction of arrow e, and the part 161 of the paper feed lever falls into the groove 172 of the paper feed cam 17. Since the paper feed control lever 18 and the paper feed lever 16 are already disengaged, the paper feed lever 16 swings along the paper feed cam 17. This swing causes the paper feed roller 11 to rotate in cooperation with the paper feed pawl 15 and the paper feed ratchet wheel 14 to feed the printing paper 3 by a predetermined amount. The paper feed cam 17 further rotates and the cam portion 173
The paper feed lever is also swung in the groove portion 174 to feed the paper. The cam portion 173 has a slightly smaller diameter than the cam portion 171, so that when the paper feed lever 16 is pushed up by the cam portion 173, the paper feed control lever 18 and the paper feed lever 16 do not engage with each other. At this time, the paper feed control lever 18 is already
is returned to the position where it engages with the paper feed lever 16 by the spring 20. Up to now, paper has been fed twice, but the last paper feed (third paper feed) is the same as normal paper feed. This is done by rotating the paper feed control lever 18 (not shown) using a cam or the like in the direction of arrow f, and during this time, the groove 1 of the paper feed cam
Since 76 faces the part 161 of the paper feed lever 16, the paper feed lever 16 swings again and feeds the paper for the third time. When the paper feed cam 17 goes around once, the cam portion 171 engages with the paper feed lever 16 again, returning to the original standby state. The above is the paper fast-feeding operation. When the electromagnet 10 is energized from timing pulses 4 to 8, the ribbon position switching lever 7 also tries to be attracted in the direction of arrow d, but at this time the ink ribbon frame 5 has already been moved. Since the ink ribbon is disengaged from the ink ribbon reset cam 8, it is locked in the first position of the ribbon position switching lever 7, and since the frictional force in this part is very large, the ribbon position switching lever 7
is not attracted.

Note that normal paper feeding is performed only by the above-mentioned third paper feeding operation without energizing the electromagnet 10 and therefore not performing the first and second paper feeding operations.

As explained above, according to the present invention, if one electromagnet 10 is energized at the first timing, the color of the ribbon can be changed, and if it is energized at the second timing, the paper can be fast-forwarded. This makes it possible to share expensive parts (electromagnets) and make them into one, making it possible to provide a small-sized printer that is very inexpensive, including parts costs and assembly costs.

Furthermore, only one driving transistor for driving the electromagnet and one spark killer diode are required, which further reduces the cost.

Further, according to the present invention, since there is only one electromagnet, the space can be reduced and a compact printer can be provided, which is very effective.

[Brief explanation of drawings]

FIG. 1 is a specific example of a timing chart of a conventional small printer. FIG. 2 is a perspective view of a specific example of a small printer according to the present invention, in which 1 indicates a type wheel;
2 is a platen, 3 is printing paper, 4 is a two-color ink ribbon, 5 is an ink ribbon frame, 6 is a spring, 7 is a ribbon position switching lever, 8 is an ink ribbon reset cam, 10 is an electromagnet, 11 is a paper feed roller,
12 is a paper feed roller shaft, 13 is a paper press roller, 1
4 is a paper feed ratchet wheel, 15 is a paper feed pawl, 16 is a paper feed lever, 17 is a paper feed cam, and 18 is a paper feed control lever. FIG. 3 is a timing chart of the small printer of FIG. 2 according to the present invention.

Claims (1)

[Scope of Claims] 1. A paper feed roller, a paper presser roller that presses the paper feed roller through the printed paper, a paper feed ratchet wheel coaxially mounted with the paper feed roller, and a paper feed roller that is centered on the shaft. a paper feed lever that swings and rotates; a paper feed cam that engages with the paper feed lever to swing and rotate the paper feed lever and intermittently rotates the paper feed ratchet wheel; a paper feed control lever that locks the paper feed lever with the lever; a ribbon frame that guides the multicolor ink ribbon to a printing position; a spring member that biases the ribbon frame in one direction; a ribbon position switching lever that engages to selectively switch the color of the multicolor ink ribbon to the printing position; an ink ribbon reset cam that engages the ribbon frame and returns the ribbon frame to its initial position; and the paper It has an electromagnet that attracts and swings the feed control lever and the ribbon position switching lever, and when the electromagnet is energized, the paper feed cam locks the paper feed lever and the color of the multicolor ink ribbon is changed. A small printer characterized in that the ink ribbon reset is performed at a first timing when the ink ribbon reset cam locks the movement of the ribbon frame and a paper feeding operation is performed.