JPH0367872B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement of a printer in a data processing device, and in particular to a cylindrical platen having protrusions arranged in a spiral manner on its outer circumferential surface, and a cylindrical platen having protrusions formed on the platen in a spiral direction. A recording medium is interposed between a plurality of hammers having perpendicular protrusions and arranged in the axial direction of the platen, and the recording medium is moved in a direction perpendicular to the axis of the platen in relation to the rotational position of the platen. This invention relates to a dot matrix printer that prints figures, characters, symbols, etc. by selectively driving the hammer and striking the platen in relation to the feeding position.

Conventional impact-type dot matrix printers are small and inexpensive, and have become popular as printers that can clearly print many characters and symbols on a recording medium. As an attempt, cross-point dot matrix printers have begun to appear here and there. However, the cross-point dot matrix printer has a cylindrical platen with a spiral projection of a constant width formed on the outer periphery, and a linear projection that is approximately orthogonal to the spiral projection of the platen, and has a linear projection that is approximately perpendicular to the spiral projection of the platen. interposing a recording medium between a plurality of hammers arranged in a direction, and associating the recording medium with the rotational position of the platen, and associating the recording medium with a feeding position in a direction perpendicular to the axis of the platen; Graphics, characters, symbols, etc. are printed by selectively driving the hammer to impact the platen, so the shape of each dot is determined by the width of the spiral protrusion on the platen and the spiral shape. It is a small square formed by the protrusion and the width of the hammer that is approximately perpendicular to it, and its size can only be changed by methods that generate noise, such as double striking, and clear character or graph printing is not possible. Nakatsuta.

In view of these points, it is an object of the present invention to provide a compact and inexpensive device that can be used to create graphics or many types of characters.
An object of the present invention is to obtain a printer capable of printing symbols and the like on a recording medium at a desired density.

Still another object is to obtain a printer that can print in color by mixing three primary colors.

The gist of the present invention for achieving the above object is to include a cylindrical platen having a spiral shape on its outer peripheral surface, and a hammer having a linear protrusion substantially perpendicular to the spiral direction of the helical protrusion. and selecting the hammer in relation to the rotational position of the platen and in relation to the feeding position of a recording medium disposed between the platen and the hammer in a direction perpendicular to the axis of the platen. In a cross-point dot printer that prints characters, symbols, figures, etc. by driving the platen to impact the platen through the recording medium, a unit of spiral protrusions formed on the outer periphery of the platen. A predetermined length is obtained by continuously changing the area per length, a plurality of spiral protrusions of the predetermined length are arranged in series, and the hammer is energized in relation to the rotational position of the platen. By appropriately selecting and impacting the area of the intersection of the spiral protrusion and the hammer, characters, symbols, figures, etc. are printed at a desired density.

The configuration of the present invention will be explained below based on the drawings.
FIG. 1 is a perspective view showing the outline of the main structure of the first embodiment, FIG. 2 is an exploded view showing the platen of the first embodiment in an expanded state, and FIG. 3 is a diagram showing the platen and hammer of the first embodiment. Fig. 4 is a side view showing the hammer support and drive structure; Fig. 6 is an explanatory diagram showing the interaction relationship;
The figure is an exploded view showing the expanded state of the platen of the second embodiment.

First, the structure of the first embodiment will be explained using FIGS. 1, 2, 3, and 4. Reference numeral 1 denotes a motor, which is fixed to a frame (not shown) and has a motor shaft 1a that rotates when energized. Note that illustrations and descriptions of lead wires, drive circuits, control circuits, etc. for energizing the motor 1 are omitted. A voter pulley 2 has teeth on its outer periphery and is fixed to the motor shaft 1a. Reference numeral 3 denotes a platen shaft, which is rotatably supported by a frame (not shown). A platen shaft pulley 4 has teeth on its outer periphery and is fixed to the platen shaft 3. Reference numeral 5 denotes a synchronized belt, which is placed between the motor pulley 2 and the platen shaft pulley 4, and is provided to transmit the power of the motor 1, that is, the rotational movement of the motor shaft 1-a, to the platen shaft 3. Reference numeral 6 denotes a platen, which is fixed to the platen shaft 3, as shown in FIG. 2, to continuously change the area per unit length to a predetermined length, and to form a spiral protrusion of the predetermined length. A plurality of spiral protrusions are arranged in series, and a separating member 6b is provided between each spiral pitch of the protrusions 6a to prevent the recording medium 33 from accidentally coming into contact with the protrusions 6a. It is fixed. The isolation member 6
b is made of a resilient material such as rubber sponge, and has an outer diameter slightly larger than the outer diameter of the protrusion 6a. In this embodiment, it is made of a rubber or sponge-like material, but it can also be made of a metal or plastic having spring properties. Reference numeral 7 denotes a platen gear, which is fixed to the platen shaft 3 and has tooth profiles formed on its outer periphery. Reference numeral 8 denotes a transfer roller shaft, which is rotatably supported by a frame (not shown). Reference numeral 9 denotes a transfer roller, which is fixed to the transfer roller shaft 8, and has a spiral projection 9a having the same diameter as the platen 6 and spiraling in the opposite direction at the same pitch as the spiral of the projection 6a formed on the outer periphery of the platen 6.
is formed on the outer periphery. Reference numeral 10 denotes transfer roller grease, which is fixed to the transfer roller shaft 8 and has tooth profiles formed on the outside. The transfer roller gear 10 has the same number of teeth as the platen shaft 7, meshes with the platen gear 7, and has the protrusion 6a and the spiral protrusion 9a.
are constructed so that they rotate while always in contact with each other. Reference numeral 11 denotes an ink roller shaft, which is rotatably supported by a frame (not shown). Reference numeral 12 denotes an ink roller, which is made of a rubber-like material and is fixed to the ink roller shaft 11, and is formed into a so-called sponge shape having non-independent cells, and contains ink in the bubbles. The ink roller 12 has a cylindrical shape, and the ink roller shaft 1
Even when the ink roller 1 rotates, the outer periphery of the ink roller 12 and the spiral protrusion 9a of the transfer roller 9 are always kept in contact with each other. Reference numeral 13 denotes an ink roller gear, which is fixed to the ink roller shaft 11 and has tooth profiles formed on its outer periphery. The ink roller gear 13 is configured to mesh with the transfer roller gear 10 so that the ink roller 12 rotates as the transfer roller 9 rotates. A first worm 14 is fixed to the platen shaft 3. 1
Reference numeral 5 denotes a connecting shaft, which is rotatably supported by a frame (not shown). Reference numeral 16 denotes a first worm wheel, which is fixed to the connecting shaft 14, has a tooth profile formed on its outer periphery, and meshes with the first worm wheel 14 by the tooth profile, and when the platen shaft 3 rotates in the direction of the arrow, the connecting shaft 15 is configured to rotate in the direction of the arrow. A second worm 17 is fixed to the connecting shaft 15. A feed roller shaft 18 is a shaft for driving a recording medium feeding means (not shown), and is rotatably supported by a frame (not shown). Reference numeral 19 denotes a second worm wheel, which is fixed to the feed roller shaft 18 and has a tooth profile formed on its outer periphery and meshes with the second worm wheel 17 due to the tooth profile, and when the connecting shaft 15 rotates in the direction of the arrow, the feed roller shaft 18 is configured to rotate in the direction of the arrow. 20 is a first timing disk, which is connected to the feed roller shaft 18;
10 long holes 20a are formed at equal angular intervals. 21 is the first timing sensor;
a light emitting element that is attached to a frame (not shown) and emits a luminous flux that passes through the elongated hole 20a;
It includes a light receiving element that receives the light beam passing through the elongated hole 20a and converts it into an electrical signal. 2
A second timing disk 2 is fixed to the platen shaft 3, and has 21 long holes 22a formed at equal angular intervals. Reference numeral 23 denotes a second timing sensor, which is attached to a frame (not shown) and is connected to the elongated hole 22.
It incorporates a light emitting element that emits the light beam that passes through the passage point a, and a light receiving element that receives the light beam that has passed through the elongated hole 22a and converts it into an electronic signal.
Note that illustrations and descriptions of lead wires and drive circuits for conducting energization and signal transmission processing to the first timing sensor 21 and the second timing sensor 23 are omitted. A third timing disk 24 is fixed to the platen shaft 3 and has one elongated hole 24a. 25 is a third timing sensor, which is attached to a frame (not shown);
It has a built-in light-receiving element that receives the light beam that has passed through the elongated hole 24a and converts it into an electrical signal. Reference numeral 26 denotes a hammer, which has a hammer driving coil 26a inside as shown in FIG. 27 is hammerhead,
The platens 6 are fixed to the tips of the hammers 26, respectively.
It is slightly tilted with respect to the axial direction. Reference numeral 28 denotes a hammer support plate spring, which is made of an elastic material and has one end fixed to the frame 31 and the other end fixed to the hammer 26, respectively, as shown in FIG. 26 is supported so as to be movable back and forth with respect to the platen 6 without tilting in any of the up, down, left, and right directions, and the rear end of the hammer 26 is pressed against a stop piece 32a of a hammer stopper 32 attached to a frame 31. There is. Reference numeral 29 denotes a first permanent magnet, which is fixed to a frame (not shown) close to above the hammer 26, and has magnetic poles arranged parallel to the direction of movement of the hammer 26. 30 is a second permanent magnet,
They are fixedly disposed on a frame (not shown) close to the lower side of the hammer 26, and have opposite magnetic poles facing the first permanent magnet 29.

Next, the operation of the structure of the first embodiment when it functions as a line printer will be explained based on the respective drawings. In FIG. 1, when the motor shaft 1a of the motor 1 rotates in response to a start command, the platen shaft 3 rotates in the direction of arrow A via the motor pulley 2, synchro belt 5, and platen shaft pulley 4. Therefore, the platen 6, platen gear 7, first worm 14, and second timing disk 22 also rotate together. Due to the rotation of the platen gear 7, the transfer roller 9 is rotated via the transfer roller gear 10 at the same rotational speed as the platen 6, and the spiral protrusion 9a rolls while constantly in contact with the plurality of protrusions 6a of the platen 6. do. Further, due to the rotation of the transfer roller gear 10, the ink roller 12 rotates in the direction of arrow E through the ink roller gear 13 while constantly contacting the spiral protrusion 9a of the transfer roller 9, and due to the contact pressure, the ink roller The ink oozing from the transfer roller 9 sequentially adheres to the spiral protrusion 9a of the transfer roller 9. The attached ink is further transferred to the platen 6.
are sequentially attached to the protrusions 6a. Here, as described above, the recording medium 33 is close to the platen 6, but since the separating member 6b protrudes more than the protrusion 6a, the ink adhering to the protrusion 6a may accidentally adhere to the recording medium 33. There's nothing to do. On the other hand, due to the rotation of the first worm 14, the feed roller shaft 1 is
8 rotates in the direction of arrow C at a rate of 1 rotation for every 110 rotations of the platen 6. As the feed roller shaft 18 rotates, the recording medium 33 moves upward. Further, the first timing disk 20 rotates as the feed roller shaft 18 rotates, and the first timing sensor 21 outputs one timing signal every time the feed roller shaft 18 rotates by 36 degrees. The second timing disk 22 and the third timing disk 24 rotate, and every time the platen 6 rotates 120 degrees/7, the second timing sensor 23 outputs one timing signal to reset the integrating circuit in the control circuit. . The integrator circuit then begins to integrate the constant voltage. The third timing sensor 25 outputs one timing signal every time the platen 6 rotates once. In such a state, printing is performed based on the print data and the print command at a timing obtained by a timing signal generated from the timing signal of the first timing sensor 21 and the voltage value integrated by the integrating circuit in the control circuit. . That is, when a print command signal is input to the printer, a control circuit (not shown) uses the timing signals from the first timing sensor 21 and the third timing sensor 25 to move a dot to a desired horizontal position in a predetermined row on the recording medium 33. The output of an integrating circuit that serves as an analog timer in the control circuit indicates that the protrusion 6a of the platen 6 has reached a suitable position to be struck by the corresponding hammer head 27, and the voltage value corresponding to the desired dot width is detected. When it is sensed by the output of a comparator that determines whether or not the hammer 26 has been reached, a drive pulse is applied to the hammer drive coil 26a of the corresponding hammer 26.

The signal circuit and timing relationship during this time will be explained using FIGS. 7 and 8.

The output TP from the bootstrap circuit increases with time according to the signal TRiG from the second timing sensor 23, and when it exceeds the dot width signal WiDTH applied in advance to the comparator 701, the output HAMMER of the comparator 701 becomes high level. The rising edge is used as the hammer head drive signal. The dot shape as mentioned above and
FIG. 8 shows a relationship diagram of the above-mentioned signals, including the relationship of TRiG. As is clear from FIG. 8, by appropriately applying a WiDTH signal proportional to the required dot width _DW , it is possible to print with any dot width.

The hammers 26 to which the driving pulses have been applied fly toward the platen 6 against the force of the hammer support plate springs 28, and the hammer heads 27 bend the separating member 6b via the recording medium 33 and push the protrusion 6a of the platen 6.
The ink adhering to the protrusion 6a is transferred to the recording medium 33 in delicate square shapes with various side ratios. In this way, one hammer head 27 can print 3 characters or symbols consisting of 5 dots horizontally and 7 dots vertically.
Digit printing is performed, and one line of print data is printed on the recording medium 33.
After that, when it is detected by the timing signals of the first timing sensor 21 and the third timing sensor 25 that the next print line on the recording medium 33 has been reached, the first line is printed in the same way as above. Then, in the same manner, each print line is printed one after another. In the embodiment described above, the feed roller shaft 18 always rotates at a constant speed, so the hammer head 27 is slightly inclined with respect to the axis of the platen 6, but the feeding operation of the recording medium 33 is sufficient to print one dot line. To do each end, hammerhead 2
7 must be configured parallel to the direction of the axis of the platen 6.

Next, the structure of the second embodiment will be explained using FIGS. 5 and 6. Note that the isolation member 6b is omitted in FIGS. 5 and 6. In this embodiment, printing can be performed in two colors using two types of dot areas. Note that the structure other than the description below is the same as that of the first embodiment. Reference numeral 106 denotes a platen, which has the same structure as the platen 6 of the first embodiment, but has a spiral protrusion 1 whose width changes in the axial direction as shown in FIG.
06a and 106b are arranged half a pitch apart like a double thread screw. Reference numeral 109 denotes a first transfer roller, which has the same structure as the transfer roller 9, but a spiral protrusion 109a is formed in a spiral shape in the opposite direction at the same pitch as the spiral of the protrusions arranged on the platen 106. The spiral protrusions 109a are formed to rotate while constantly contacting the first protrusions 106a arranged on the platen 106. A second transfer roller 209 has the same structure as the first transfer roller 109, and has a spiral protrusion 20.
9a is a spiral projection formed in the opposite direction at the same pitch as the spiral of the projections arranged on the platen 106, and the spiral projection 209a is formed on the platen 106.
It is formed so as to rotate while constantly contacting the second protrusions 106b arranged in a row. A first ink roller 112 has the same structure as the ink roller 12 and contains black ink, and is configured to rotate while constantly in contact with the spiral protrusion 109a of the first transfer roller 109. . 2
Reference numeral 12 denotes a second ink roller, which has the same structure as the first ink roller 112 and contains red ink.
It is configured to rotate while always in contact with 09a. The hammer head 27 is arranged in the same manner as in the first embodiment shown in FIG.

Next, the operation of the structure of the second embodiment when it functions as a line printer will be explained based on the drawings. In FIG. 5, the platen 106 is rotated in the same manner as in the first embodiment, and as the platen 106 rotates, the first
The transfer roller 109 and the first ink roller 112 rotate while rolling with each other, and the second transfer roller 209 and the second ink roller 212 also rotate while rolling with each other. Therefore, the first ink roller 112
The black ink contained in
Spiral protrusion 106 whose width changes in the axial direction of 06
The red ink that adheres to the second ink roller 212 and is contained in the second ink roller 212 adheres to the helical protrusion 106b whose width changes in the axial direction of the platen 106 via the helical protrusion 209a of the second transfer roller 209. . Subsequently, when the hammer head 27a is driven in the state shown in FIG. 6, for example, the hammer head 27a is driven.
When the hammer head 7a is driven, the hammer head 27a hits the protrusion 106a through the recording medium 33, and the protrusion 1
The black ink attached to 06a is the recording medium 3.
3 is transferred in the form of a small dot. Also hammerhead 27
When the hammer head 27b is driven, the hammer head 27b hits the protrusion 106d via the recording medium 33, and the protrusion 106d
The red ink attached to 6b is the recording medium 33
It is transferred in the form of a large dot. Further, for example, when the platen 106 further rotates from the state shown in FIG. 6 and the wide part of the protrusion 106a comes to a position facing the hammer head 27a, the hammer head 27a hits the protrusion 106b through the recording medium 33. When the medium 33 comes to the narrow part of the red horizontally long small rectangular protrusion 106a, it is struck with the hammer head 27a, and a red vertically long small square is transferred onto the recording medium 33. The above functions are the same for other hammer heads. Therefore, by selectively driving the hammer 26 at appropriate timing, it is possible to display dots in black or red at any position, and even in large or small areas, so that thin and bold dots can be changed to black, respectively. can be printed in red. Although each of the above-mentioned embodiments has a configuration capable of printing in one color and two colors, the number of threaded rows of protrusions formed on the surface of the platen is three, and each thread is colored, for example, with yellow, magenta, and yellow. By configuring the printer to supply cyan ink and appropriately selecting each color and the width of the protrusions, it is possible to print out color figures with shading. By making the dots finer, natural color photographs can also be printed. Further, although an ink roller is used in this embodiment, the same effect can be obtained by using an ink ribbon.

As is clear from the above description, according to the present invention, the shape of the dots can be changed without using a method that generates noise such as double dot printing, so character printing or graph printing can be realized with a desired density. When an ink roller is used, the effect of the present invention is even greater because the density of the transferred dots is not affected by the printing pressure. Furthermore, the printing speed can be relatively high compared to the method using double striking.

[Brief explanation of drawings]

The drawings all relate to the present invention, and FIG. 1 is a perspective view showing the outline of the main structure of the first embodiment, and FIG.
A developed view showing the expanded state of the platen of the embodiment,
FIG. 3 is an explanatory diagram showing the interaction relationship between the platen and the hammer in the first embodiment, FIG. 4 is a side view showing the structure of supporting and driving the hammer, and FIG. 5 is an explanatory diagram showing the interaction between the platen and the hammer in the second embodiment. FIG. 6 is an exploded view showing the platen of the second embodiment in an expanded state, FIG. 7 is a signal circuit diagram, and FIG. 8 is a timing explanatory diagram. 6,106... platen, 6a, 106-a,
106-b...protrusion, 27...hammer.

Claims (1)

[Claims] 1 A cylindrical platen having a spiral protrusion formed on its outer peripheral surface, and a hammer having a linear protrusion substantially orthogonal to the spiral direction of the helical protrusion, the hammer being associated with the rotational position of the platen; The hammer is selectively driven in relation to the feeding position of a recording medium disposed between the platen and the hammer in a direction perpendicular to the axis of the platen, and the platen is moved through the recording medium. In a cross-point dot printer that prints characters, symbols, figures, etc. by impact, the area per unit length of the spiral protrusion formed on the outer periphery of the platen is continuously changed to print a predetermined length. A plurality of helical protrusions of a predetermined length are formed in series, and the hammer is energized in relation to the rotational position of the platen to form a part where the helical protrusions and the hammer intersect. A cross-point dot printer that prints characters, symbols, figures, etc. at a desired density by appropriately selecting and striking an area.