JPS583879A - Cross hammer type dot printer - Google Patents

Abstract

PURPOSE:To increase the printing speed of a printer by arranging two printing hammers provided on a printing head in parallel each other with an interval corresponding to a specific multiple of the lateral pitch of a dot matrix. CONSTITUTION:Plural lines of elongated protruded part 2 are formed, in parallel each other, on the outer circumference of a rotary drum 1 in the direction of its axis and a printing head 5 equipped with 2 pieces of print hammer 10, 10a to be electromagnetically driven which is fixed to a carriage 6 supported by 2 pieces of guide shaft 7 to be freely slidable are provided to oppose each other through a recording medium 3 and an ink ribbon 4 so that they can be moved in the direction of the axis of the drum 1. The hammers 10, 10a are caused to change their opposing positions in parallel each other with an interval corresponding to n multiple (n>1) of the lateral pitch Ph of a dot matrix against the protruded part 2 in its longitudinal direction and simultaneously they are caused to drive alternately with an interval cycle of the time the protruded part 2 requires to move the dot matrix vertically by its vertical pitch Pv.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a black and white dot printer capable of forming dot matrix characters and the like at high speed.

The cross hammer type dot 1 rim is provided with a rotating drum facing the print head, and this rotating drum is provided with a plurality of parallel protuberances extending in the axial direction on its outer peripheral surface.
The print head includes a print mark extending substantially transversely to and facing the ridge. A dot is formed by the cooperation (collision) between the printing mark and the raised portion. That is, the ridge changes its cross position in the column (longitudinal) direction with respect to the print hammer due to the rotation of the rotating drum, and the print hammer changes its cross position in the column (vertical) direction depending on the spacing of the print head.
The cross constant mass can be changed in the transverse) direction.

The rotation of the rotary drum and the spacing of the print head are performed in parallel, and the print hammer is selectively driven so that the print hammer collides with the ridge and creates a dot on the recording medium at the point of intersection (impact) between the two. It is designed to form a .

The present invention enables high-speed printing in such a cross hammer type dot printer VC, and embodiments thereof will be described below with reference to the drawings.

In FIG. 1, a rotating drum 1 is driven to rotate continuously, for example, in a counterclockwise direction, and has a plurality of raised portions 2'le on its outer peripheral surface. The rotating drum has a length equal to or longer than the width of the recording medium 5, and has a raised portion 2 along its entire length.
are formed extending parallel to the axial direction. A print head 5 faces the rotating drum 1 via a recording medium 3 and an ink ribbon 4, and is configured as shown in (2).A carriage 6 of the print head 5 can freely slide on two guide shafts 7. A support plate 9 is fixed to the carriage 6 via screws 8. 10. Two printed lines. i
The oa extends in a direction substantially transverse to the raised portion 2 and is arranged in an opposite orientation.

Since its support structure and electromagnetic drive device are all (ltfj-), one of the printing hammers 10 will be explained, and the other printing hammer 10aK will have a lower case suffix a attached to the corresponding symbol.Printing hammer 10IIi movable yoke The movable yoke 11 is fixed to the tip of the leaf spring 12.
2Fi, spacer plate 15 and front yoke 14 are fixed to support plate 9 via pins 15. front yoke 1
A ring-shaped permanent magnet 16 and a cap-shaped rear yoke 17 are fixed to the rear surface Fi of 4. A column-shaped center yoke 18 is provided at the center of the bottom of the rear yoke 17 and protrudes toward the center of the front yoke 14. Opposed to the front surface of
The front surface of the center yoke 18 is being attracted by the air against the spring force of the center yoke 18. A release coil 1 is arranged around the central yoke 18.
9 is wound, and by throwing this release coil 19 [11fi VC, the above magnetic flux can be canceled out. This
Due to the VC, the movable yoke 12 is released from being biased by magnetic attraction with the center yoke 18, and the printing hammer 10 moves forward by the spring force of the leaf spring 12 and collides with the protrusion 2 of the rotating drum 1.

FIG. 2 shows the relative relationship between the tips of the printing hammers 10 and 10a and the rotating drum 2, and shows the relative relationship between the printing hammers 10 and 10a and the rotating drum 2.
, 10aij Due to the continuous spacing of the print head 5, the opposing position changes in the row (horizontal) direction with respect to the raised portion 2K, and in parallel with this, the raised portion 2 is moved by the printing hammer 10°10aK due to the rotation of the rotating drum 1. On the other hand, the opposing position changes in the column (vertical) direction. From the relationship of the relative transition of the opposing positions of the printing hammers 10, 10a and the raised portion 2, the printing hammers 10, 10a
It is actually inclined at a predetermined angle with respect to the awning ridge 2.

Figure 5 shows an example of the character "A" in the dot matrix formed by this printer.
0,10Fi horizontal pinch ph of this dot matrix n
times (n is an integer greater than or equal to 1, this example is nwl
They are arranged in parallel at intervals equivalent to 64 DK. The driving timing of both printing hammers 10 and 10a is such that they are driven alternately with an interval period of time required for the raised portion 2 to move the vertical pinch Pv of the dot matrix. That is, in FIG. 2, when the raised part 2 is in the first row position rc6, the printing hammer 10 is driven, and then when the raised part 2 is in the second row position, the printing hammer 10a is driven, and so on. The printing hammers 10, 10a are driven alternately. That is, when one printing hammer 10 is responsible for forming dots on odd-numbered lines, the other printing hammer 10a is responsible for forming dots on even-numbered lines. To explain in more detail, two rows of dots separated by n rows are formed almost simultaneously by the printing hammers 10 and 10aK;
The printing hammer 10a selectively forms dots on each even numbered line, and the subsequent printing hammer 10a selectively forms dots on each even numbered line.
& means that the first printing hammer 10 forms dots in the odd row (r), and then forms dots in the even row in the next column n columns. In Fig. 3, l is marked: E indicates a dot formed by the printing hammer 10a, respectively.

Note that the design of the support structure of the printing hammers 10, 10a and their electromagnetic drive device can be changed as appropriate.

As described in detail above, according to the present invention, since characters, etc. are formed using the main printing hammer in a cross hammer type dot 1 printer, the printing speed increases, and at this time, the inner printing hammers are not driven at the same time but alternately. Because it is being driven, the peak value of the drive current is the same as when there is only one printing hammer, so there is no need to change to a large capacity power supply circuit.
The relative relationship between the printing hammer of the ``!lfc print head and the raised part of the rotating drum is also the same as when there is only one printing hammer, so the design is easy. Also, the inner printing hammers are not driven at the same time. The noise is low.

[Brief explanation of the drawing]

Fig. 1 is a side sectional view of the cross-no-marker dot printer of the present invention, Fig. 2 is an enlarged view showing the relative relationship between the printing I/marker of the print head and the rotating F-ram protrusion, and Fig. 3 is a cross-sectional view of this printer. This is an enlarged view showing an example of the character "A" in the dot matrix formed. 1... Rotating drum, 2... Protuberance, 5...
Print head, 10.10&-...Print I/mma, P
h...horizontal pinch of dot matrix, Pv...vertical pitch of dot matrix, D...internal printing]・
Parallel spacing of symbols, applicant: Seikosha Co., Ltd., Patent Attorney Mogami

Claims (1)

[Scope of Claims] A print head equipped with two electromagnetically driven print hammers is provided in front of a rotating drum so as to be movable oppositely across the recording medium and in the axial direction of the rotating drum, On the outer peripheral surface of the rotary drum, a number of protrusions are provided on the rotary shaft, which sequentially face both of the printing hammers and whose opposing position can be changed in the row direction of the dot matrix with respect to the print hammer. Formed by stretching in the axial direction, the above-mentioned both printing hammers, the horizontal pitch ph of the dot matrix
extending in parallel in a direction that substantially intersects the raised portions with an interval corresponding to n (an integer greater than or equal to nij) times n, and extending in the row direction of the dot matrix with respect to the raised portions by movement of the print head. The cross-no-matrix don't printer is characterized in that the two printing hammers are selectively driven alternately with a time period for KIL in which the raised portion moves the vertical pinch Pv of the dot matrix. .