JPS59167288A - Apparatus for preventing lift-up of ink ribbon - Google Patents

Abstract

PURPOSE:To prevent trouble such as an omission of characters by preventing an ink ribbon from being caught by a corner even if said ribbon is unstably run, by covering the corner of a front yoke end part arranged to a hammer unit by a sub-ribbon separator. CONSTITUTION:A sub-ribbon separator 22 is attached to the surface of a front yoke part 17 provided to the side of an ink ribbon 20 so as to cover the corner 17' of said yoke part 17 and provided with holes corresponding to the front surfaces of printing pins 12 so as to impart no trouble to printing and extends upwardly to also cover the surface of a hammer cover 70. An ink ribbon 20 runs between the sub-ribbon separator 22 and a ribbon separator 21 but, because the sub-ribbon separator 22 is contacted with said ribbon only in a narrow width, imparts almost no resistance to paper feed and the running of the ink ribbon 20.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an ink ribbon lifting prevention device for a dot line printer.

Many types of printers have been commercialized and are used as output devices for computers and the like. Among these printers, the slowest one is a printer called a dot line printer, which has font flexibility and high-speed printing function, and is rapidly becoming popular. One particularly important problem with this dot line printer is the ink ribbon lifting system. The mechanism and ink ribbon lifting of such a dot line printer will be explained below with reference to FIGS. 1 to 3.

A dot line printer is a printer that prints characters, figures, etc. made up of a dot matrix using a printing hammer ■ that can print dots, and this printing hammer 11f! : The hammer unit 10 is characterized in that a large number of hammer units 10 are mounted at equal intervals in the girder direction and reciprocate. As shown in the figure, the printing hammer (2) is a plate spring with a printing bottle (ν) disposed at its tip. This leaf spring is arranged in a magnetic circuit consisting of a permanent magnet B1, an L-shaped yoke plate 14, a comb yoke 16 and a front yoke 17 in which a release electromagnetic coil 15 is arranged.

The comb yoke 16 is fixed to the yoke plate H by bolts (not shown). Yoke plate 1 via front yoke 17 rB, printing hammer 11 and permanent magnet 13
4 with bolts 18. Due to the magnetic circuit configured as described above, the printing hammer 11 is normally connected to the permanent magnet 13.
The magnetic attraction force causes the comb yoke 16 to be attracted and held at one end of the comb yoke 16 in a bent shape JJ. The printing is the electromagnetic coil 1!
This is done by exciting 5. That is, the magnetic attraction force of the permanent stone 13 is canceled out by the excitation of the electromagnetic coil 15, the printing mark 11 is released from the comb yoke 16, and the printing pin m is moved through the ink ribbon 20 and paper 30. Hit the platen 50. At this time, ink ribbon 2
The ink impregnated into the paper 30 is transferred to the paper 30 to print dots.

A large number of the above-mentioned printing marks are arranged at equal intervals in the direction of the 19 digits, forming a hammer unit loe. The hammer unit 10 has slide bearings 19 at both ends thereof, and is supported by a shaft 62 fixed to a mechanical frame 60 with bolts 61 so as to be movable in the digit direction. The drive unit 10 (not shown) reciprocates in the digit direction. The total amplitude of this reciprocating motion has at least the distance between adjacent prints...7711. A tractor (not shown) moves between sheets.
It is sent in dot row units in the upward direction in the figure. Printing is performed by controlling the reciprocating movement of the printer unit 10, paper feeding, and driving of the printer printer 10, and characters, figures, etc. are formed in a dot matrix. The ink ribbon 20 is tape-shaped as shown in FIG. 2, and runs along the front surface of the front yoke 17 in the digit direction. More specifically, the ink ribbon 20 runs diagonally as shown in the figure with respect to the printing bottle of the printing hammer 11 arranged in a straight line in the printer unit 10. A ribbon separator 21 is disposed between the ink ribbon 20 and the paper 30. The ribbon separator 21 is made of a thin stainless steel plate, and has a function of preventing the ink ribbon 20 from being lifted upward when the paper 30 is fed. Furthermore, paper 30 and ink ribbon 20
It has a function of separating the ink ribbon and preventing the paper 30 from being stained by the ink ribbon. The ribbon sensor 21 has a duct for cooling the electromagnetic coil 15 above the hammer unit 10, which is provided with a hole through which the printing pin passes during printing. . . . A mechanical frame 70 is installed on a mechanical frame 60 via a stand 63. A press halter 71 is disposed above the paper cover 70 and serves as a guide for stably feeding the paper 30. Furthermore, in order to facilitate the loading of the ink ribbon 20, the platen 50 side surface of the print head <-70 is
It is shaped close to the front yoke 17 side as shown in the figure. That is, this is to prevent the lower end of the ink bottle 20 in the width direction from getting caught in the tip of the front yoke when loading the ink bottle 20. The ink ribbon 20 travels while being alternately wound up by two spools (not shown) of the tape. Therefore, the ink ribbon 20 alternately repeats running from left to right or right to left in FIG.

In the dot line printer configured as described above, there is a problem in that the ink ribbon 20 is lifted up. ink ribbon 20
Lifting is a phenomenon in which the ink ribbon 20 is swung up and down for some reason and is moved away from the front of the printing bottle. This results in omitted characters, which is an unacceptable problem for printers. One of the biggest causes
One is the perforation 31 which is the separation for each IQ of paper 30.
It is in. -6VC perforation 31 has a convex or concave shape toward the hammer unit IO side as shown in the figure. When this portion passes between the platen 50 and the printing bin 2, the ink ribbon 20 is tightened between the ribbon separator 21 and the front yoke 17. As a result, the ink ribbon 2
The resistance when 0 runs in front of the machine 10 becomes a very large value. The size of this resistance is paper 3
Although it differs depending on the type of paper 30, in general, the thicker the paper 30, the larger the paper 30. The ink ribbon 20 is stretched with a tension of Nm1jl. However, when the perforation 31 of the thick paper 30 passes as described above,
Since a resistance greater than the above-mentioned tension is generated, the ink ribbon 20 is swung in the digit direction, that is, in the running direction, together with the hammer unit n that is reciprocating in the digit direction. This shaking causes the ink ribbon 20 to run unstable. Sometimes, when the ink ribbon 20 is swung up and down, the lower end in the width direction of the ink ribbon 20 gets caught in the corner 17' of the front yoke shown in section A in Figure 2. At this time, when the ink ribbon prisoner is traveling from left to right, front yoke 1
It gets into the gap between the upper end of the hammer 11 and the hammer cover 70, and it gets separated from the printing pin of the hammer 11. That is, the ink ribbon 20 shown in FIG. 3 with two fish wins is obtained. As a result, a major problem occurs in which all digits are omitted.

In order to prevent this problem, the front yoke 17 can be made larger and the corner 17' of the front yoke 17 can be extended upward, but this makes it difficult to manufacture the front yoke 17.
This is not a good idea because there are problems such as an increase in the mass of the unit 10 and Alt misalignment with the hammer cover 70.

Furthermore, as mentioned above, when loading the ink ribbon, the lower end of the ink ribbon 20 is placed in the gap between the tip of the front yoke 17 and the hammer cover 70 (1 to 2
There is also the problem that the ink ribbon 20 enters the printer, making it difficult to load the ink ribbon 20.

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the above-mentioned drawbacks of the prior art, and to provide a glazed dot line printer that prevents the ink ribbon from lifting and at the same time facilitates the loading of the ink ribbon.

The present invention is based on Takiguchi's understanding that the cause of the above problem is caused by the gap between the front yoke and the front yoke.
A part of the gap is removed so that it does not interfere with the running of the ink ribbon and paper feeding.

An embodiment of the present invention will be described with reference to FIGS. 4 and 5. The configuration around the hammer unit 10 of the dot line printer is the same as the conventional example described above, except for the parts described below, so the explanation thereof will be omitted.

Hammer cover L-10 (7,) A sub-ribbon separator of the present invention is attached to the ink ribbon 20 side surface of the front yoke 17 so as to cover the corner 17' of the front yoke 17.
1. Attach the stainless steel thin plate 22. The sub-ribbon separator 22 has a hole provided in the front surface of the printing pin so as not to interfere with printing. Furthermore, it extends upward from the upper end surface of the printing pin of the front yoke 17, and the platen 5081jl of the printer cover 70
Covers up to the O side. When installing the sub-ribbon separator 22, use the pole that fixes the front yoke 17)
It is carried out by 18K. The ink ribbon 20 runs between the sub-ribbon separator 22 and the ribbon separator 21. Sub-ribbon separator 22 and hammer cover 7
Since an appropriate gap is provided between the two and the two, there is little contact between the two, and I≠wear rarely occurs. Further, since the sub-ribbon separator 22 contacts only a narrow width with the surface of the front yoke 17 on the platen 50 side as shown in the figure, it provides almost no resistance to paper feeding of the paper 30 and regular movement of the ink ribbon 20.

If the sub-ribbon separator 22 is arranged in a dog-like manner so as to cover all the directions of the front yoke 17 like the ribbon separator 21, distortion and warpage of the sub-ribbon separator 22 and paper gaps will be avoided. If the gap between the front yoke 17 and the platen 50 is too small, resistance to paper feeding of the paper 30 and running of the ink ribbon 20 will be large, making it impractical.

In the above embodiment, the sub-ribbon separator 22 is a fully shrunk thin plate and is arranged so as to be in close contact with the surface of the front yoke 17, but it may have the shape and arrangement shown below.

The magnetic circuits of the printing marks 11 disposed at both ends of the hammer unit IO are different from the magnetic circuits of the printing marks 11 other than both ends. This is because only the outside of the printing marks 11 at both ends are free from the printing marks 11, leaving a space. In order to compensate for this difference, it is common to provide a plate called a dummy beam as shown in FIGS. 6 and 7. Even if this dummy hammer ■' is extended upward to hit the corner 17' of the front yoke, the sub-ribbon separator 22 (!: same effect can be obtained. It is essential to provide the dummy hammer 11' and the hammer cover 70 so that they do not interfere with each other.

According to the present invention, since the corner of the end of the front yoke disposed in the hammer unit is covered by the sub-ribbon separator, even if the ink ribbon runs unstably, it will not get caught in the corner and omit characters. This makes it possible to prevent problems such as Further, by arranging the sub-ribbon separator on the front side cuff of the hammer unit, the effect of facilitating loading of the ink ribbon is also achieved.

[Brief explanation of drawings]

Figure 1 is a cross section of the area around the hammer unit of a dot line printer, Figure 2 is a front view of the hammer unit seen from the platen side (the ribbon separator is omitted), Figure 3 is Figure 2 4 is a front view showing a part of the hammer unit in which all the sub-ribbon separators according to the present invention are installed, FIG. 5 is a sectional view of FIG. 4, and FIG. 7 is a front view showing a part of the hammer unit, and FIG. 7 is a sectional view of FIG. 6. In the figure,] 11 is a printing hammer, 12 is a printing bottle, B is Mizuku Rokuishi, 14 is a yoke plate, 15 is a '1 magnetic coil, 16 is a hacom yoke, 17
is the front yoke, the other is the bolt, 19i'i, slide bear link, u' Hatamino Nma, 17' is the corner of the front yoke, 20 is the ink ribbon, 21 is the ribbon mono 2
22 (sub-ribbon separator, 30 paper,
3 is Min/N month, 50 is platen, 60 is mechanical frame,
61 is 7" bolt, 62 is shaft, 63 is stand,
70 is a) arm cover, and 71 is a hubless holder. Patent LF, -α Person's name Hitachi Koki Co., Ltd. Sai1 3rd m ri θ 4th m ri 61 yen 1 Sairi m

Claims (1)

[Claims] Multiple prints that can print dots along the digit direction "7-Z"
``K tower-mounted fc-hammer unit, ki; A! IJ means for reciprocating the hammer unit along the digit direction, and a dot having a tape-shaped ink ribbon running on the front surface of the hammer unit in the digit direction. In the line printer, the guide for the ink ribbon traveling of the hammer unit is a plate-shaped front yoke that constitutes a part of the magnetic circuit of the printing hammer, and the guide is a plate-shaped front yoke that forms a part of the magnetic circuit of the printing hammer, and covers a corner of the tip of the front yoke. An ink ribbon lifting prevention device for a dot line printer, characterized in that a plate-shaped sub-ribbon separator is mounted on at least one end of the hammer unit.