JPH01154777A - Type position detector in printer - Google Patents

Abstract

PURPOSE:To enable a type position to be detected correctly and rapidly without providing a reset-exclusive pulse detecting means, by a method wherein, armatures are alternately made to face codes which are corresponding to types, and at the detection of a pulse by one of the armatures a pulse detected by the other armature is reset. CONSTITUTION:Armatures 25, 25 detecting codes are so disposed as to alternately come into contact with codes 24 corresponding to types. As shown in Fig.3, the respective armatures 25, 25 are constructed so that at the detection of a pulse by one of the armatures 25 a pulse detected by the other armature 25 is reset and the detection of a pulse by the former armature 25 has been prohibited until a pulse is detected by the latter armature 25. Thus, the respective armatures 25, 25 alternately set and reset a pulse. Therefore, even if the armatures 25, 25 generate chattering when coming into contact with the codes 24, the correct detection of a type position detection pulse is ensured.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a type position detection device for printers, and in particular detects the position of type in type belt type printers used on trains, etc. using mechanical contacts. The present invention relates to a type position detection device for a printer.

[Conventional technology]

FIGS. 4 and 5 show a general type printer of type bell 1, in which a pinion 4 is fitted to the output shaft 3 of a motor 2 supported by a frame 1. The rotation is transmitted to the drive pulley 7 via a pair of idle gears 5 and 6. Further, a selection lever 8 is movably disposed near the drive pulley 7, and a claw portion 9 of the selection lever 8 is attached to the drive pulley 7.
The rotation of the drive pulley 7 is stopped by fitting into the drive pulley 7. Further, an electromagnetic clutch 10 is disposed near the selection lever 8, and when the electromagnetic clutch 10 is turned on, the selection lever 8 rotates and the claw portion 9 engages with the drive pulley 7. It looks like this.

The drive pulley 7 faces one side of the frame 1, and the driven pulley 11 faces the other side of the frame 1. The driving pulley 7 and the driven pulley 11 have a large number of printed characters 14, 14 and 14 on the belt body 13.
A type belt 12 with projecting characters . . . is wound around it.

A flat platen 15 supported by the frame 1 is disposed in front of the type belt 12, and inside the type belt 12, the type belt 1 of the platen 15 is disposed.
A carriage 16 carrying a hammer member 17 for pressing two desired type bodies 14 against a platen 15 is disposed so as to be movable laterally by a mechanism not shown. In general, at the lower end of this carriage 16, when the desired type body 14 of the type belt 12 is pressed against the platen 15 by the hammer member 17, the type bodies 14 on both sides of the desired type body 14 are prevented from being printed. A pair of mask members 18 and 18 are provided on the type belt 12 with an interval of approximately one type body 14 left and right.
It is supported in a cantilevered manner so as to be located at the platen 15.

Incidentally, there are eleven gear ridges 16 so as to be returned to the home position in a free state by a spring member 19. Further, between the type belt 12 and the carriage 16, paper (not shown) is supplied to a pinch roller 20 and a paper feed roller (not shown). Further, the type bell 1-1 near the driven pulley 11
2 is provided with an ink roll 21 for applying ink to each type body 14 of this type belt 12.

Further, a code plate 23 is fixed to the lower surface of the printer main body coaxially with the drive/vJ shaft 22 of the drive pulley 7, as shown in FIG. This code plate 23 has a plurality of codes 24 indicating the position of the printed characters 14 on the printed character belt 12.
．． 24... are formed at appropriate pitches on the outer periphery,
A plurality of (two) contact pieces 25, 2 fixed to the main body 1119
Code detection unit 25a and 25a are placed on the movement locus of each code 24 to detect which typeface 14 is located at which position. In addition, the code plate 23
A sensor gear 26 is provided adjacent to the sensor gear 26 so as to follow the rotation of the code plate 23 and rotate at a predetermined speed, and a code 27 is provided on the sensor gear 26 to indicate that the printing state of the printer is at the initial position. ing. The cord 27 is detected by an initial position detecting end 28a of a contact piece 28 fixed to the main body, and it is determined whether the cord 27 is at the initial position.

Further, a plurality of conductive wires 29a, 29a are connected between the printer main body side formed in this way and the drive board section (not shown).
... are electrically connected via a built-in flat cable 29. That is, flat cable 2
Each conductive wire 29 led out from the printer body side end of No. 9
The terminals 30, 30, . . . of the electromagnetic clutch 10 are connected to the ends of the contact pieces 25, 28 and the motor 2 by soldering.

In the conventional printer, printing commands are sent from the drive board to each component via the flat cable 29, and printing is performed while the position of the type belt 12 is detected by each contact piece 25.2B.

That is, the rotation of the motor 2 is transmitted from the pinion 4 to the drive pulley 7 via the idle gears 5 and 6, causing the drive pulley 7 to rotate. Accordingly, the type belt 12 rotates together with the driven pulley 11.

When the electromagnetic clutch 10 is turned on, the selection lever 8 rotates,
Each claw portion 9 fits into the drive pulley 7 to stop the rotation of the drive pulley 7 and stop the desired type body 14 at a position facing the key I7 ridge 16. Then, by driving the hammer member 17 in the carriage 16 and pressing the type body 14 against the paper facing in front of the platen 15, the ink applied to the type body 14 is transferred to the paper, and printing of the first digit is completed. Next, after the electromagnetic clutch 10e is turned off and the carriage 16 is carried up, the above-described operation is repeated for the necessary digits and printing for one line is completed, and the carriage 16 is returned to the home position by the spring member 19. Then, the MS is transferred by one line using a pinch roller 20 and a paper feed roller (not shown), and the next line is printed.

[Problem that the invention seeks to solve]

However, in the conventional printer J3, a plurality of codes 2/1.24 formed on the outer periphery of the code plate 23 are connected to the code detection end of the contact piece 25. 25a, 25a are used for detection. When such mechanical contacts are used, the cord detection ends 25a, 25a of the contact pieces 25.25 vibrate and cause chattering, which makes accurate detection difficult. The problem was that it couldn't be done.

Therefore, conventionally, as shown in FIG.
One of the contact pieces 5 is used as a setting contact for detecting pulses corresponding to the printed characters, and the other contact piece 25 is used for detecting pulses generated approximately in the middle of the printed characters and resetting or setting the pulses corresponding to the printed characters. After the position of the type is detected by the setting contact piece, the pulse by the setting contact piece is not detected until the pulse by the reset contact piece is detected.

Thereby, even if a character position detection pulse generated by the setting contact piece is generated multiple times due to chattering, it is possible to accurately detect the character position.

However, in order to reset the pulse corresponding to the type, it is necessary to provide a pulse detection means separate from that for detecting the position of the type. However, if the size of the code plate is limited, the number of pulses to be detected is limited.

The present invention has been made in view of these points, and it is an object of the present invention to provide a type position detection device for a printer that can accurately and quickly detect the type position n without providing a pulse detection means exclusively for reset. The purpose is to

[Means for solving problems]

In order to achieve the above object, the printer type position detection device according to the present invention is provided with a code plate on the printer body, on which a plurality of codes indicating the position of the type are formed at appropriate pitches in the circumferential direction. At the same time, a plurality of contact pieces are arranged so that their tips face the movement locus of each of the codes, and the position of the type is detected by detecting pulses generated when each of the contact pieces comes into contact with each of the codes. In the type position detection device of the printer, each contact piece is made to correspond to the code corresponding to the type character, and when a pulse is detected by one of the contact pieces, the pulse detected by the other contact piece is reset. It is configured in such a way.

[For production]

According to the present invention, each of the Iyr contact pieces is made to correspond alternately to the code corresponding to a printed character, and each contact piece is configured to set and reset each other, so that one contact piece is used to generate a printed character position detection pulse. By preventing the pulse from one of the contacts from being detected after detecting the character position detection pulse from the other contact H, the character position detection pulse from the contact piece is generated multiple times due to chattering. It is possible to accurately detect the position of printed characters even when Furthermore, there is no need to detect a pulse dedicated to reset, and the position of printed characters can be detected quickly.

〔Example〕

Embodiments of the present invention will be described below with reference to FIGS. 1 to 3.

1 and 2 show an embodiment of the present invention, and the same parts as in FIGS. 4 and 5 are given the same reference numerals.

In this embodiment, a rectangular small printed circuit board 31 is fixed to the frame 1 on the bottom side of the printer main body, and a plurality of conductive backs 32, 32, . is forming. and,
Each contact piece 25 is provided at the inner end of each conductive pattern 32,
28 and terminal 30 are soldered. In this embodiment, there are three contact pieces 25 for detecting the code 24 of the code plate 23, two of them on both sides are contact pieces 25.25 for detecting the position of printed characters, and the center one is a common contact. Piece 25'
Furthermore, one out of every two 1a pieces 28 for detecting the position of the sensor gear r26 is used for common use. Then, in the flat cable 29 having seven conductive wires 29a, each conductive wire 29a is inserted from above into a small hole bored at the outer end of each conductive pattern 32 of the small printed circuit board 31, and Thereafter, each conducting wire 29a and each conductive pattern 32 are connected by soldering.

In addition, in this embodiment, the contact piece 25. which detects the code.
25, as shown in FIG. 2, are arranged so as to come into contact with the cords 24 corresponding to the printed characters alternately, and each of these contact pieces 25, 25, as shown in FIG. When a pulse is detected by the contact piece 25, the pulse detected by the other contact piece 25 is reset, and the pulse by the one contact piece 25 is detected until the pulse by the other contact piece 25 is detected. We are trying not to do that. That is, each of the contact pieces 25, 25 is set and reset alternately.

Therefore, in this embodiment, even if chattering occurs when the contact piece 25°25 contacts the cord 24, the character position detection pulse can be accurately detected and normal operation can be performed. can. Moreover, since the position of the type is detected by each contact piece 25.2.5, it is possible to detect practically twice as many pulses while keeping the size of the code plate 23 the same. Therefore, the position of the printed characters can be detected even more quickly.

Note that the present invention is not limited to the above embodiments,
It can be changed as necessary.

[Effect of four shots]

In this way, in the printer type position detection device of the present invention, a plurality of contact pieces are made to correspond alternately to the codes corresponding to the type characters, and each contact piece is configured to let and reset each other. When chattering occurs in the contact piece by controlling so as not to detect the pulse from one of the contact pieces until the type position detection pulse is detected by the other contact piece after the type position detection pulse is detected by the contact piece. However, it is possible to accurately detect the position of the printed characters. In addition, since there is no need to detect a pulse dedicated to reset, it is possible to detect more type position detection pulses with a compact configuration, which has the effect of enabling rapid type position detection. .

[Brief explanation of the drawing]

1 to 3 show an embodiment of the printer type position detection device of the present invention, in which FIG. 1 is a plan view of a part of the printer, FIG. 2 is a bottom view of FIG. 1, and FIG. The figure is a line diagram showing the detection pulse of each contact piece, Figure 4 is a plan view showing a conventional general printer, Figure 5 is a bottom view of a part of Figure 4, and Figure 6 is a conventional printer. Shows the detected pulse by the piece? FIG. 7... Drive pulley, 12... Type belt, 15...
・Platen, 23... Code board, 25, 2, 8...
Contact piece, 25a... Cord detection end, 28a... Initial position detection end, 29... Flat cable, 29a...
Conductor, 30...Terminal, 31...Small printer board, 3
2... Continuity pattern. Figure 1 Figure 2 Figure 3 Figure 6 Figure 4

Claims (1)

[Claims] A code plate is provided on the printer body, and a code plate is provided with a plurality of codes formed at appropriate pitches in the circumferential direction to indicate where the type is located, and a plurality of contact pieces are arranged so that their tips are on the movement locus of each of the codes. In a type position detection device for a printer that detects the position of a type by detecting a pulse generated when each of the contact pieces comes into contact with the code, A type position detection device for a printer, characterized in that the type position detection device for a printer is configured to correspond to each code alternately, and when a pulse is detected by one of the contact pieces, a pulse detected by the other contact piece is reset.