JPH0212190B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a serial impact type printing device using a type wheel.

Construction of conventional examples and their problems In recent years, instead of printing devices using petal-shaped type wheels with type at the tips of radially formed spokes, printers have been replaced with conventional flat type type wheels in order to speed up printing. A printing device has been developed that uses a type cup in which the spokes of the type wheel are bent into a cup shape to reduce the moment of inertia. Since this type cup has two levels of type, the type can be selected by the two movements of rotation and shifting, reducing the moment of inertia and shortening the type selection time, making high-speed printing possible.

FIG. 1 is a diagram showing the printing mechanism of a conventional printing device using a type cup as described above.
0 is a platen that holds the printing paper 11; 12 is a printing section 14a, 14 at the tip of a large number of spokes 13;
B is a type cup arranged in two rows. A printing hammer 16 is arranged on the back side of the printing characters 14a and 14b located on the side of the platen 10, and when a signal is input, the printing hammer 16 presses the printing part 14b or 14a against the printing paper 11. Type section 14
There is an ink ribbon 17 between b or 14a and the printing paper 11, and printing is performed. Type cup 1
2 is attached to a type holding member 18, and since the convex portion 19 of the type holding member 18 is fitted into the hole or notch 15 of the type cup 12, rotational movement can be transmitted. The type holding member 18 is supported on a rotating shaft 19a of a motor 19 so as to be rotatable and movable up and down. Rotating shaft 1 of motor 19
A rotation transmission member 20 is fixed to the rotation transmission member 9a, and a pin 21 fixed to the rotation transmission member 20 and a protrusion 22 of the type holding member 18 are movable relative to each other in the longitudinal direction of the rotation shaft 19a of the motor 19. The rotation of the motor 19 is transmitted to the type cup 12 via the type holding member 18, but
The type cup 12 can be freely moved up and down.

23 is a rotary solenoid, and an eccentric shaft 24 is attached to its output shaft. Eccentric shaft 24
is fitted into a long hole drilled at one end of a shift lever 26 rotatably attached to a fixed part (not shown) with a pin 25, and a type holding member 18 is fitted at the other end of the shift lever 26. A pin 27 that fits into the groove 18a is provided. The rotation of the rotary solenoid 23 causes the shift lever 26 to move to the pin 25.
The type holding member 18 is moved up and down by rotating around the center.

When printing, the motor 19 and rotary solenoid 23 rotate to rotate and move the type cup 12 up and down to select a type, and then the print hammer 16 operates to complete the printing operation.

However, the conventional printing device configured as described above requires a complicated mechanism to rotate and move the type cup up and down, so it is not suitable for miniaturization of the device, and furthermore, due to its structure, frictional force is high. Due to the large size, there were problems such as an increase in the load on the motor and rattling due to wear.

Purpose of the invention The purpose of the present invention is to be suitable for miniaturization, and to reduce friction.
An object of the present invention is to provide a printing device with excellent reliability due to reduced wear and the like.

Structure of the Invention The printing device of the present invention supports a type cup rotatably around its rotation axis, and
An electromagnetic solenoid having a movable iron core (armature) that, when energized, moves the type cup in the longitudinal direction of its axis of rotation (for example, in the vertical direction) and brings the type portion of each row to the striking position of the printing hammer. By using this, the type cup can be moved efficiently.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 2 is a partially cutaway side view of a printing device according to an embodiment of the present invention. In the figure, 40 is a platen that holds printing paper 41. 42 is a type cup, which has a plurality of spokes 44 extending vertically from the vicinity of the outer periphery of a disc portion 43 at predetermined intervals, and the outer tip of each spoke 44 has type portions 45a, 45b arranged in two upper and lower stages. is formed. A gear 46 is formed on the outer periphery of the disc portion 43 of the type cup 42 and meshes with a gear 48 fixed to the rotating shaft of a motor 47. In addition, holes or notches 43a are provided in the disk portion 43, and convex portions 50 such as pins implanted in the type mounting member 49 are fitted into the holes or notches 43a. 49 and the type cup 42 can be rotated and moved up and down together.

On the back side of the type part 45a or 45b, there is an actuating body 5 of a printing hammer 51 disposed on a fixed base 60.
1a is located. When a signal is applied to the printing hammer 51, the operating body 51a is projected to the right in FIG. Then, since the spokes 44 have appropriate elasticity, the printed portions 45a or 45b are pressed against the printing paper 41. Type section 4
Since an ink ribbon 52 is provided between 5a or 45b and the printing paper 41, printing is performed.

47 is a motor for controlling the rotational position of the type cup 42, which is connected to a control circuit (not shown).
The rotational position is controlled by . The gear 48 attached to the motor 47 has a thickness such that it remains in mesh with the gear 46 of the type cup 42 even when the type cup 42 is shifted vertically. Reference numeral 53 denotes an electromagnetic solenoid for moving the type cup 42 up and down, and this solenoid is attached to the lower surface of a fixed base 60, on which the printing hammer 51 is attached, in the inner space of the type cup 42.

Note that when a shift signal is input, this electromagnetic solenoid 53 connects the type mounting member 49 to its lower end.
The armature 54 with the attached armature is moved upward by electromagnetic force.

As a result, as shown in FIG.
From the position in which the type cup 42 is lowered so that the lower type portions 5a face each other (hereinafter referred to as the first position), the type cup 42 is lowered so that the lower type portion 45b faces the tip of the actuating body 51a of the printing hammer 51. 42 is brought to the raised position (hereinafter referred to as the second position).

FIG. 3 is a side sectional view showing an example of the electromagnetic solenoid 53, in which a shaft 6 is provided in the center of the fixing base 60.
1 is fixed, and a cylindrical rotor 62 and an armature 54, which is a movable iron core, are supported by the shaft 61 in a vertical positional relationship.
The rotor 62 is made of a magnetic material, and a sliding bearing 63 is press-fitted into the center thereof. Therefore, the rotor 62 can freely rotate on the shaft 61. Although the rotor 62 can also move in the axial direction, it normally rests on a flange portion 61a provided on the shaft 61 due to its own weight. The armature 54 is also made of magnetic material, and has sliding bearings 55, 56 in its center.
is press-fitted. Therefore, armature 54
is rotatable on the shaft 61 and movable in the longitudinal direction of the shaft. A coiled spring 64 is provided between the armature 54 and the collar portion 61a of the shaft 61, and biases the armature 54 downward to bring the type cup 42 to the first position. The armature 54 is attached to an E-ring 65 whose lower end is attached to the shaft 61 by the urging force of a coiled spring 64.
It is stopped at the position where it hits.

In this position, the slider washer 66 is sandwiched between the slide bearing 56 and the E-ring 65, so the rotational resistance of the armature 54 is very small.

The upper part 54a of the armature 54 is tapered and the upper part 54a of the armature 54 is tapered.
The lower part of the rotor 62 facing the upper part 54a of the rotor 4 also has the same tapered recess 6 as the upper part of the armature 54.
2a is formed. Yokes 67 and 68 are made of magnetic material and have substantially convex and concave cross sections, respectively, and are coupled to surround the coil 69.

The yoke 67 accommodates the rotor 62 in a non-contact manner in the center, and the upper part 54a of the armature 54 is inserted into the recess 6 of the rotor 62 from below.
A through hole 67 large enough to allow entry and exit into 2a.
It has a. Inner peripheral portions 67b and 68a of the through holes of the yokes 67 and 68 face the outer peripheral surfaces of the rotor 62 and the armature 54, respectively, with appropriate gaps 70 and 71 maintained therebetween.

When the coil 69 is energized, the yokes 68, 67 to
Magnetic flux is generated in the magnetic path formed by the rotor 62 and the armature 54, and the armature 54 is connected to the rotor 6.
2 is attracted by magnetic attraction. armature 5
The moving distance of 4 is equal to the amount of shift of the type cup 42.

FIG. 4 schematically shows the outline of the magnetic flux generated inside the electromagnetic solenoid 53 when the coil 69 is energized, and the magnetic flux is represented by a broken line in the figure. Since the magnetic flux passing through the gaps 70 and 71 is directed in the radial direction and is uniform over the entire circumference, no radial force is generated in the rotor 62 and armature 54. However, the magnetic flux passing through the gap G between the tapered upper part 54a of the armature 54 and the tapered recess 62a of the rotor 62 generates a force in the longitudinal direction of the shaft, compressing the coiled spring 64 and moving the armature 54 upward. The rotor 62 and armature 54 are attracted to each other.
The rotor 62 and armature 54, which are attracted to each other, are pulled together by the shaft 61 due to the force of the coiled spring 64.
Since the rotor 62 stops at the position where it touches the flange portion 61a of the letter cup 42, the shifted position of the type cup 42 is always constant. Since there is no lateral pressure acting on the bearing even after suction, the rotational resistance of the armature 54 is extremely small. Further, after the attraction, the gap G becomes smaller and the magnetic resistance decreases, so the excitation force for maintaining the attraction of the armature 54 can be reduced. Since the suction portion of the armature 54 is tapered, a large excitation force is not required even at the suction start position where the gap G is large.

When the coil 69 is de-energized, the armature 5
4 is its own weight and coiled spring 64
It moves downward and waits at the position where the lower end touches the E-ring 65.

As described above, according to this embodiment, the armature connected to the type mounting member to which the type cup is attached can be moved up and down directly by magnetic force without contact. Furthermore, the number of moving parts is reduced, reliability is improved, and the device can be made smaller. Further, since the rotational resistance when rotating the type cup is small and the load inertia is also small, effects such as a reduction in the load on the motor are produced.

In the above-described embodiment of the present invention, the motor and the type cup are connected by a gear in order to rotate the type cup, but the connection between the motor and the type cup is not limited to the one using a gear, and other methods may be used. , for example, as shown in the conventional example, the shaft 6
It is also possible to employ a structure in which the rotating shaft of the motor is arranged coaxially with 1 and a rotation transmitting member is used.

Figure 5 shows an electromagnetic solenoid 53 used in the present invention.
FIG. 3 is a side sectional view showing another embodiment of the invention. This will be explained below, but the same reference numerals will be given to those having the same functions as those explained in the embodiment shown in FIG. 3, and the redundant explanation will be omitted here. In the embodiment shown in FIG. 5, a cylindrical (or ring-shaped) permanent magnet 72 is fixed to the lower surface 67c of the yoke 67. The permanent magnet 72 is magnetized in the thickness direction, and a ring-shaped core 73 made of a magnetic material is fixed to the lower surface. The inner circumferential surface 73a of the core 73 faces the outer circumferential surface of the armature 54 with a required gap 74 in between.

Figures 6 and 7 show the electromagnetic solenoid 53 in Figure 5.
Fig. 6 schematically shows the state of the magnetic flux generated inside the armature 54. Fig. 6 shows the armature 54 in its lowered return position, and Fig. 7
4 is in the upward shift position.

In FIG. 6, the solid line represents the magnetic flux generated by the permanent magnet 72, and the broken line and the one-dot chain line represent the magnetic flux generated by the coil 69 when a shift signal is input. As shown in FIG. 6, when the armature 54 is in the return position, the magnetomotive force of the permanent magnet 72 causes the core 73 to the gap 74 to the armature 54 to the gap 71 to the yoke 68 to the yoke 6.
Generate magnetic flux in the magnetic path of 7. Gap 74 and Gap 7
Since the direction of the magnetic flux passing through 1 is in the radial direction of the armature 54, no force is generated to move the armature 54 in the longitudinal direction of the shaft. Note that the magnetic flux generates a force that pulls the armature 54 in the radial direction,
Since the gaps 71 and 74 are axially symmetrical, they cancel each other out and the armature 54 is not subjected to any force in the radial direction. Therefore, the sliding bearings 55 and 56 of the armature 54 are not subjected to lateral pressure, so rotational resistance is extremely small.

In the state shown in FIG. 6, when a shift signal is input to the coil 69, the yokes 67 to 68
A magnetic flux is generated in the magnetic path between the gap 71 and the armature 54. When the distance between the armature 54 and the rotor 62 is large, most of the magnetic flux emitted from the armature 54 does not pass through the rotor 62 but passes through the flange portion 67c at the bottom of the yoke 67. When the armature 54 begins to move upward as the coil 69 is energized and the distance from the rotor 62 becomes smaller, the magnetic flux emitted from the armature 54 flows from the rotor 62 to the gap as shown by the dashed line in FIG. 70 and enters the yoke 67. Armature 54 and yoke flange portion 67d, or armature 54 and rotor 6
The magnetic flux passing between the two generates a force that moves the armature 54 in the longitudinal direction of the shaft. In this case as well, the forces that pull the armature 54 in the radial direction cancel each other out, so no lateral pressure is generated, and the armature 54 can be smoothly moved and rotated in the axial direction.

Here, when the armature 54 is attracted to the rotor 62, the magnetomotive force of the permanent magnet 72 generates a magnetic flux as shown by the solid line in FIG. Permanent magnet 72 ~ core 73 ~ gap 74 ~ armature 54
The armature 54 is magnetically attracted to the rotor 62 due to the magnetic flux passing through the magnetic path of the rotor 62, the gap 70, the yoke 67, and the permanent magnet 72. Another magnetic path is permanent magnet 72 ~ core 73 ~ gap 74 ~
Magnetic flux is also generated from the armature 54 to the gap 71 to the yoke 68 to the yoke 67 to the permanent magnet 72, but no force is generated in the armature 54. Further, since this magnetic path has a larger magnetic resistance than the aforementioned magnetic path, most of the magnetomotive force of the permanent magnet 72 acts to attract the armature 54 to the rotor 62. Therefore, even if the coil 69 is de-energized, the armature 54 remains moved upward, and the type cup 42 remains in the second position.

When a return signal (a signal flowing in the opposite direction to the shift signal) is applied to the coil 69 in order to return the armature 54 to the return position, a magnetic flux as shown by the broken line in FIG. 7 is generated. Of the magnetic flux generated by the permanent magnet 72, the magnetic flux passing through the armature 54 to the rotor 62 is canceled out by this magnetic flux, and a portion of the magnetic flux is detoured from the armature 54 to the yoke flange portion 67d as shown by the dashed line. Therefore, the armature 54 is no longer subjected to the attraction force in the longitudinal direction of the shaft due to the magnetic force of the permanent magnet 72, so it moves downward due to its own weight and the action of the coiled spring 64, returns to the return position, and stops.

By energizing the coil 69 as described above, the armature 54 is attracted to the rotor 62 by electromagnetic force, and after being attracted, the attracted state is maintained by the magnetomotive force of the permanent magnet 72. Then, when the coil 69 is energized in the opposite direction to that during shifting, the suction is released and the armature 54 returns to the return position. Therefore, by supplying a shift signal and a return signal to the coil 69, the type cup 42 is moved from the first position to the second position.
position (select type 45b),
It can be moved from the position to the first position (selecting the type 45a).

According to the embodiment shown in FIG. 5, in addition to the effects obtained in the embodiment shown in FIG. can get.

In addition, in the embodiment shown in FIG. 5, the permanent magnet 72
Although it is arranged inside the yoke 68, it is not limited to this location, and the same effect can be obtained by placing it outside the solenoid or inside the movable iron core, for example. In addition, in order to cancel the shift, a current opposite to that used during the shift was passed through the coil, but it is also possible to easily adjust the current value by using a coil dedicated to shifting and resetting. It is.

Effects of the Invention As is clear from the above description, in the printing device of the present invention, the type cup is directly moved up and down by the movable core (armature) of the electromagnetic solenoid. This simplifies the mechanism and reduces the number of moving parts, which improves reliability and maintainability and allows the printing device to be made smaller. In particular, by arranging the electromagnetic solenoid in the interior space of the type cup, further compactness can be achieved. In addition, in a solenoid, by rotatably supporting the part that attracts the movable core with an appropriate gap from the yoke, it is possible to reduce the rotational resistance of the type cup and to significantly reduce wear on the rotating part. Effects can be obtained. Moreover, since the rotational resistance is reduced and the inertial load is also reduced, the output of the motor for rotating the type cup can be reduced, and the positioning accuracy of the type cup is improved.

Furthermore, when permanent magnets are used, as illustrated in Figure 5 above, special electrical energy is not required to hold the type in the shifted state, and resetting can be done with a small amount of energy. This also has the excellent effect of being able to be driven by the printer, which brings about a great effect in realizing a power-saving and compact printing device.

[Brief explanation of drawings]

Fig. 1 is a partially cutaway side view showing an example of a conventional printing device, Fig. 2 is a partially cutaway side view showing an embodiment of the present invention, and Fig. 3 is an example of an electromagnetic solenoid used in the present invention. 4 is an enlarged side sectional view of the main part to explain the operation of the electromagnetic solenoid,
FIG. 5 is a side sectional view of another example of the electromagnetic solenoid used in the present invention, and FIGS. 6 and 7 are enlarged side sectional views of essential parts of the electromagnetic solenoid shown in FIG. 5 in various states. 40...platen, 41...printing paper, 42...
...Type cup, 43...Disc part, 44...Spoke, 45a, 45b...Type part, 51...Printing hammer, 52...Ink ribbon, 53...Electromagnetic solenoid, 54...Armature, 60...Fixed Base, 61... Shaft, 62... Rotor, 64...
...Coil spring, 67,68...Yoke,
69...Coil, 72...Permanent magnet, 73...Core.

Claims (1)

[Scope of Claims] 1. A plurality of flexible spokes are arranged in parallel at predetermined intervals on the outer periphery of a disk-shaped member to form a cup shape, and each of the spokes has a printed portion at its outer tip. A type cup formed in two stages in the length direction of each spoke, a printing hammer for hitting the type part on the printing paper, a motor for rotating the type cup, and a type cup with its rotation axis centered on the type cup. The electromagnetic solenoid is provided with an electromagnetic solenoid that moves in the longitudinal direction to bring the type portions of each stage to the striking position of the printing hammer, and the electromagnetic solenoid includes a rotor made of a magnetic material rotatably disposed on a shaft, and a movable iron core rotatably provided on the shaft and movable between a first position spaced apart from the rotor by a predetermined distance and a second position in contact with or close to the rotor; A yoke made of a magnetic material arranged at least partially in close proximity to each of the rotor and the movable core so as to form a magnetic circuit including the movable core. Device. 2. The printing cup is configured to include a gear part provided coaxially with the disc-shaped member, and the motor is connected to a connecting gear that engages with the gear part. The printing device according to item 1.