JPS5913987B2 - line printer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a line printer having a type drum in which type characters are arranged on the outer peripheral surface of a cylinder.

10 In general, there are demands for line printers to diversify type types, improve print quality, and make printing devices smaller, more reliable, and lower in price.

In addition, since the printing paper used for line printers has different characteristics depending on the purpose, line printers 15
Evening is required. In a conventional line printer, all characters are arranged in the circumferential direction of the outer peripheral surface of the type drum for each digit so that one line of printing can be completed with one rotation of the type drum.

For this reason, in conventional type drums, the diameter of the type drum has increased as the type of type has diversified into 20 types, resulting in an increase in the size of the printing device and an increase in the moment of inertia of the type drum, resulting in deterioration in the starting performance of the printing device. . In general, the larger the type drum, the more expensive it is. In addition, in the conventional line print 25 fern, when thick paper, 90 x 9 paper, or multi-sheet copy paper is used as the printing paper, the rigidity of the printing paper is high, so when printing the desired type, it is adjacent to the target type. A side print phenomenon occurs in which printed characters are printed, which deteriorates print quality. In view of these points, it is an object of the present invention to reduce the diameter of the type drum without reducing the type or size of the type, and to prevent the side print phenomenon by adapting to the characteristics of the printing paper. The object of the present invention is to provide a line printer that satisfies the above-mentioned requirements for line printers as much as possible.

, □Ku To achieve the above objects, the gist of the present invention is as follows:
A plurality of typed characters are arranged in a right-handed and left-handed spiral shape on the outer peripheral surface of the cylinder, and an area adjacent to the typed characters in the generatrix direction of the cylinder has a portion without typed characters roughly equivalent to the one typed character. a type drum on which the type characters are arranged; a rotating means for rotationally driving the type drum around a cylindrical rotation center axis; and a reciprocating drive of the type drum in the axial direction of the cylindrical rotation center in synchronization with the rotation means. A line printer is constituted by a type drum reciprocating means and a printing means for selectively recording desired type on the printing paper with respect to the type drum.

Embodiments of the present invention will be described below based on the drawings.

First, the arrangement of the type on the type drum that holds the type will be explained. FIG. 1 is an explanatory diagram showing an expanded layout of the type arrangement of a conventional type drum, where A indicates the pitch of the type in the digit direction, and B indicates the pitch of the type in the circumferential direction.

FIG. 2 is an explanatory diagram showing the expanded layout of the type drum of the embodiment of the present invention, where C is the digit pitch of the type, D is the circumferential pitch of the type, and E is the right-handed and left-handed type, which will be described later. The amount of deviation in the circumferential direction of each of the printed characters in groups 50 and 52 is shown. As shown in FIG. 2, the type arrangement of the type drum of the present invention is arranged around the periphery of the conventional type drum on a single right-handed spiral in which the pitch C in the digit direction is set to twice the pitch A in the digit direction of the conventional type drum. A right-handed type group 50 that accommodates all types of type by arranging each type with a circumferential pitch D that is twice the direction pitch B and making three revolutions around the type drum, and a right-handed type group 50 that has the same digit direction as the single right-handed spiral. Arranging each type on a single left-handed spiral having a pitch C with the same circumferential pitch D as the right-handed type group 50,
A left-handed type group 52 accommodates all types of type by rotating the type drum three times, and each type in both the right-handed type group 50 and the left-handed type group 52 is a double type in the circumferential direction. The right-hand type type group 50 is arranged with a displacement amount E that is half the circumferential pitch D of the group (the displacement amount E is the same amount as the circumferential pitch B of a conventional type drum), and the right-hand type type group 50 is designed to print odd-numbered digits. ,
Further, the left-hand type character group 52 is arranged to print even numbered digits. By arranging each type as described above, as shown in FIG. 2, the direction of the generating line of the type drum according to the present invention is
Adjacent to each printed character in the digit direction there is a portion with no printed characters, which is approximately equivalent to one printed character.

The specific arrangement of the type of type on the type drum in this example is as follows:
As shown in the figure, the first volume of the right-handed type group 50 gives the symbol!
In the second volume, 22 types of type from the number 7 to the alphabet L are arranged, and in the third volume.
22 types of characters are arranged according to the volume, from the alphabetical letter M to the kanji symbol, and 66 types of characters are accommodated in the right-handed type group 50, and the third volume.

Similarly, the first volume of the left-handed type group 52 arranges 22 types of characters from symbol ゛ to alphabet A, the second volume arranges 22 types of characters from alphabet B to alphabet W, and the third volume arranges 22 types of characters from symbol ゛ to alphabet A. 22 types of characters from the alphabet X to the symbol 10 are arranged according to the eyes, and 66 types of characters are accommodated by the left-handed type group 52 and 3 volumes.
As described above, in the type drum of the embodiment according to the present invention, as shown in FIG. By arranging the type in a spiral, 66 types of type can be accommodated.

On the other hand, in order to accommodate the same number of types of type in the conventional type drum as in this embodiment, 66 types of type must be arranged in the circumferential direction of the type drum. Therefore, the diameter of the type drum of this embodiment is two-thirds of the diameter of the conventional type drum, and the type drum is made smaller. FIG. 4 shows a first embodiment of a line printer according to the present invention, in which a drum shaft 1
The type drum 12, which is fixed at zero, is pivoted to be rotatable and axially movable.

On the outer peripheral surface of the type drum 12, there is a right-handed type group 5 as described above.
0 and a left-handed type group 52 are arranged in alignment. In FIG. 3, a first resultant motion 1 of movement in the rotational direction shown in direction F and movement in the axial direction shown in direction G, and a movement in the rotational direction shown in direction F and the axis shown in direction H A drum drive is provided for alternately imparting to the type drum 12 both a resultant movement and a second resultant movement J due to the directional movement. In the first embodiment shown in FIG. The drive device includes a drive gear mechanism as a rotating means for rotationally driving the type drum 12, and a cam device as a type drum reciprocating means for reciprocating the type drum 12 in the axial direction.

A pinion 14 fixed to the drum shaft 10 is connected to the pinion 1
The main shaft 18 of the gear 16 is rotatably supported by a frame (not shown).
This is also connected to a well-known motor mechanism (not shown), and the main shaft 1 is operated by a motor device whose startup is controlled by a printing command.
8 is rotated. This rotation causes the drum shaft 10 to rotate through the gear 1.
6 and pinion 14. drum shaft 1
0 is rotatably supported by a frame (not shown) so as to be slidable in its axial direction. Ring 20 is drum shaft 1
A pin 22 fixed to the ring 20 is provided so as to be rotatable to zero but not slidable in the axial direction.
It engages with the long groove 26 of No. 4. The swing lever 24 is supported so as to be swingable about a fixed shaft 28 fixed to a frame (not shown). The cam followers 30 and 32 provided on the swing lever 24 are cam surfaces 34 of positive cams constituted by a pair of bell cams 34 and 35 fixed to the main shaft 18.
a, 35a, and as the main shaft 18 rotates, it moves according to the cam surfaces 34a, 35a, and the type drum 1
2 in its axial direction. FIG. 5 shows a cam diagram of the positive cam.

In FIG. 5, the horizontal axis represents the rotation angle of the main shaft 18 and the type drum shaft 10, the vertical axis represents the amount of movement of the type drum 12 in the axial direction, M represents one rotation of the main shaft 18, and N
indicates one rotation of the type drum 12, which is 7N-M, P indicates the printing start point, N1 indicates the first rotation of the type drum 12, and N2 indicates the second rotation of the type drum 12. Similarly, N7 indicates the seventh rotation of the type drum 12. Q and R indicate the amount of movement of the type drum 12 in the axial direction, and in this embodiment, the values of Q and R correspond to six digits. As shown in FIG.
During the first, second, and third rotations, which are the first three rotations, the cam curve is given in a straight line so that the axial movement of the type drum 12 (movement in the direction of arrow K in FIG. 4) is performed at a constant speed. A curve for reversing the direction of movement is provided for reversing the axial movement of the type drum 12 in the first half of the fourth rotation of the type drum 12. During the last three rotations from the second half of the fourth rotation to the first half of the seventh rotation, the type drum 12 moves in the axial direction (movement in the direction of arrow L in FIG. 4).
, the cam curve is given in a straight line in order to perform at a constant speed, and the seventh
A curve for reversing the direction of movement is again provided for reversing the axial movement of the type drum in the second half-turn of the rotation. The above two curves for reversing the moving direction are curves such that the change in acceleration caused by reversing the type drum 12 is smooth. Near the type drum 12,
A printing means constituted by a printing hammer device and an ink ribbon (not shown) is provided, and a printing paper (also not shown) is provided, and the outer peripheral surface of the type drum 12 is applied to the printing paper via the ink ribbon. Print the selected type.

FIG. 4 shows a first embodiment in which a printing solenoid and a corresponding printing hammer are provided for each digit as a line printer for thick paper printing using highly rigid 90k9 paper or multi-copy paper as the printing paper. It is shown.
The printing hammer device of the first embodiment will be described below. A printing hammer 42 having the same number of printing digits is rotatably supported on a hammer shaft 40 fixed to a frame (not shown), and the printing hammer portion 42a is aligned to approach the outer peripheral surface of the type drum 12. are doing. Each printing hammer 42 is constantly urged in a direction away from the type drum 12 by a spring 44. Each printing hammer 42 is provided with a printing solenoid 46 fixed to a frame (not shown), and when an excitation current is supplied to the printing solenoid 46, the printing hammer 42
is attracted by the printing solenoid 46, and the spring 44
Each printing hammer part 42a resists the urging force of the type drum 1.
The printer is configured so that the printing operation can be performed by striking 2. According to the embodiment of the present invention, the printing operation is performed as follows.

That is, when the line printer starts printing, the type drum 12 is in the initial position, which is returned to the rightmost direction in FIG. When the first three rotations of the type drum 12, which moves in the direction of the arrow K in synchronization with the rotational movement and prints on odd-numbered digits, are completed, the movement along the drum shaft 10 is smooth due to the above-mentioned curve for reversing the direction of movement. is reversed from the direction of arrow K to the direction of arrow L. Thereafter, the type drum 12 moves in the direction of the arrow L along with the rotational movement, and when the last three rotations of the type drum in which printing is performed on even-numbered digits are completed, the movement along the drum shaft 10 is reversed in the direction of movement described above. The direction of the arrow L is smoothly reversed again in the direction of the arrow K by the curve. Although not shown, a well-known control circuit memorizes and discriminates the printed characters that move past the printing hammer part 42a corresponding to each digit, and when the printed characters that continuously pass match the desired print signal of the desired digit. Excitation current is supplied to the printing solenoid 46 of each corresponding digit, and the corresponding printed character at that time is recorded on the printing paper. Generally, the printing force by the printing hammer also acts on printed characters adjacent to desired printed characters via the printing paper.

When the force acting on adjacent printed characters is large, a side print phenomenon occurs. The force acting on the adjacent printed characters becomes smaller as the distance between the desired printed characters and the adjacent printed characters becomes longer, and as the rigidity of the printing paper decreases. In a type drum-type line printer, the type drum is cylindrical, so even when a highly rigid printing paper is used, the force acting on the characters adjacent to the printing drum in the circumferential direction through the printing paper is small. As shown in Figure 4, the number of printing hammers 4 equal to the number of printing digits.
In the first embodiment in which 2 is provided, cardboard such as 90
Even when printing on highly rigid printing paper such as K9 paper or multi-sheet copy paper, as described above, the type drum according to the present invention can print approximately one type in the area adjacent to the desired type in the generatrix direction, that is, in the digit direction. Since there is a part without corresponding type, the distance between the desired type and the adjacent type is long, and the printing force of the printing hammer when printing the desired type is adjacent to the desired type in the digit direction via the paper to be printed. The force acting on printed letters becomes smaller. Therefore, no side print phenomenon occurs. Next, as a second embodiment of the present invention, 45
A line printer for printing on thin paper using low-rigidity paper such as K9 paper or 55K9 paper as the printing paper will be described.

The second embodiment differs from the first embodiment in the printing hammer device, which is one of the components of the printing means, and since the other components are the same in both embodiments, FIG. A printing hammer device for a line printer for printing on thin paper will be described below.

In FIG. 6, a printing hammer 142 corresponding to half the number of printing digits is rotatably supported on a hammer shaft 140, and a printing hammer portion 142a of the printing hammer 142 has a width corresponding to two digits since it also serves to print two digits. They are arranged in a manner that closely corresponds to the outer peripheral surface of the type drum 12. Each printing hammer 142 is constantly urged in a direction away from the type drum 12 by a spring 144. A printing solenoid 146 is provided corresponding to each printing hammer 142. When an excitation current is supplied to the printing solenoid 146, the printing hammer 142 is attracted to the printing solenoid 146, and each printing hammer The printing operation is performed by the portion 142a hitting the type drum 12. 7 and 8, the difference between the printing hammer devices of the first embodiment and the second embodiment, especially the difference between the printing hammers, will be clarified.

In FIG. 7, which is an explanatory diagram of the first embodiment, in the developed view 12' of the type drum 12, between the digit direction pitch C having a pitch of two digits, there is a printing hammer 42 having a printing hammer width A. Two of them are arranged, forming what is called a hammer for each digit. On the other hand, the eighth example is an explanatory diagram of the second embodiment.
In the figure, one printing hammer 142 having a printing hammer width A is disposed between digit direction pitches C having two digit pitches in a developed view 12' of the type drum 12.
A so-called two-digit printing hammer 142 is configured to also print two digits, and the two-digit printing hammer 142 prints two digits. As mentioned above, in the type drum according to the present invention, the type 1 is approximately adjacent to the desired type in the generatrix direction, that is, in the digit direction.
and 45k.
Due to the low rigidity of thin paper such as 9 paper or 55k9 paper, even if a 2-digit printing hammer is used in the printing hammer device in a line printer for printing on thin paper, the force acting on adjacent characters through the paper to be printed is small. No side print phenomenon occurs.

Therefore, in a line printer for printing on thin paper, the number of printing hammers and printing solenoids can be halved. Furthermore, in the first embodiment shown in FIG. 4, a printing solenoid 46 is required for each digit, so the printing solenoid 46 is distributed at three locations, but according to the second embodiment shown in FIG. Since the number of printing solenoids 146 is reduced by half compared to the first embodiment, the printing solenoids 146 do not need to be placed in at least one of the three locations distributed in FIG.
can be accommodated, thus making the line printer more compact. Therefore, a line printer for printing on thin paper that can employ a two-digit printing hammer can achieve improved reliability, lower cost, and smaller size of the line printer by reducing the number of components such as the printing hammer and printing solenoid by half.

According to the present invention, the printing hammer device, which is one of the components of the printing means, can also be configured as follows. The printing hammers have almost the same shape as the first embodiment, and are arranged so that one printing hammer is provided for every two digits and can be moved by one digit in the digit direction.By moving the printing hammer in the digit direction, one printing hammer is formed. Press to print two digits. The printing operation of this printing hammer device will be explained below. At the start of printing, the printing hammer is set to odd-numbered digits, and the odd-numbered digits are printed by the first three rotations of the type drum. Synchronized with the reversal of the type drum's movement along the drum axis, the print hammer moves to an even numbered digit,
Even-numbered digits are printed by the last three revolutions of the type drum. In synchronization with the reversal of movement of the type drum along the drum axis, the print hammer moves to an odd numbered digit and returns to the printing start state. In the first and second embodiments described above, 66
An example has been described in which one line of printing is completed in 7 revolutions of the type drum for the type of type, but as another example where the type drum diameter is the same as that in the example, in the case of 88 type type, printing of one line is completed by 9 revolutions of the type drum. Rotating, type drum 1 for 110 type types
In the case of 132 types of type, printing of one line can be completed in 13 rotations of the type drum in one rotation. In this manner, the present invention can accommodate multiple character types without increasing the diameter of the type drum. Further, if it is desired to reduce the diameter of the type drum shown in the embodiment to about two-thirds, this can be achieved by configuring the type drum, drum, and drive device so that one line of printing can be completed by 11 rotations of the type drum. As explained above, according to the present invention, the diameter of the type drum can be reduced by arranging each type on the type drum in a right-handed and left-handed spiral, so the printing device can be downsized and the starting performance of the line printer can be improved. improves.

In addition, in the type arrangement on the type drum, there is a part with no type corresponding to approximately one type in the adjacent part of the type in the digit direction, so line printers that use highly rigid printing paper can print each digit separately. By providing a hammer, the side print phenomenon can be prevented, and by adopting a two-digit printing hammer for line printers that use printing paper with low rigidity and reducing the number of components of the printing hammer and printing solenoid by half, line printers can be improved. It is possible to achieve high reliability, low cost, and miniaturization, and to obtain a line printer that is adapted to the characteristics of the printing paper.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing a developed type arrangement of a conventional type drum, FIGS. 2 and 3 are explanatory diagrams developed and shown a type arrangement of a type drum according to an embodiment of the present invention, and FIG. The diagram is
FIG. 5 is a cam diagram of the positive cam shown in the first embodiment of the present invention, and FIG. 6 is a perspective view showing the main parts of the first embodiment of the present invention. A perspective view showing the printing hammer device of the embodiment, FIG. 7 is an explanatory diagram of the arrangement of the printing hammer on the type drum of the first embodiment, and FIG. 8 is an illustration of the arrangement of the printing hammer on the type drum of the second embodiment. It is an explanatory diagram. 10... Type drum shaft, 12... Type drum, 14... Pinion, 16...
Gear, 20... Ring, 24... Rocking lever, 30, 32... Cam follower, 34,
35...Belcome, 42,142...
Printing hammer, 46,146...Printing solenoid, 50...Right hand type group, 52...Left hand type group.

Claims (1)

[Claims] 1. It has a first type group consisting of a plurality of type characters arranged in a left-handed spiral shape on the outer peripheral surface and a second type group consisting of a plurality of type characters arranged in a right-handed spiral shape, and performs rotational movement. a type drum that reciprocates in its axial direction in synchronization with the rotational movement; and a plurality of hammers that are disposed close to the outer periphery of the type drum and parallel to the axis of the type drum and that hit the type as appropriate. , a paper conveying means for feeding printing paper disposed between the hammer and the type drum, in which a group of characters on the type drum is arranged in a direction parallel to the axis of the type drum. A line printer characterized in that a blank area with no printed characters, which corresponds to one printed character, is provided adjacent to the printed characters.