JPS6144853Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a type selection mechanism for a small-sized printer that includes a plurality of type wheels arranged.

The type selection devices that have been commonly used in the past have many drawbacks, such as a complicated mechanism, a large number of parts, an increase in the overall volume of the device, a complicated assembly process, and a large amount of power consumption. It was hot.

The present invention constitutes a type selection mechanism by combining a permanent magnet and an electromagnet, and an object thereof is to provide a type selection mechanism that is small, simple in structure, and low in power consumption, which improves the above-mentioned drawbacks.

An embodiment of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a vertical sectional view of a type selection mechanism showing one embodiment of the present invention. FIG. 2 is a plan view including a partial cross section taken along the line AA of the type selection mechanism in FIG. Figure 3 shows B- of the type selection mechanism in Figure 1.
FIG. Figure 4 is the first
FIG. 3 is a left side view including a broken surface of a main part of the type selection mechanism in the figure. FIG. 5 is an enlarged view of the main part showing the control portion of the type selection mechanism in FIG. 1.

A fixed yoke 1 made of magnetic material has a rod-shaped magnetic core 2.
A magnetic pole portion 3 formed into a concave shape is provided. The magnetic core 2 has a coil bobbin 5 wound with an appropriate number of coils 4.
is mounted on the outside and constitutes an electromagnet. The fixed yoke 1 is magnetized in synchronization with the electromagnet of the magnetic core part 2 and generates a magnetic field at the magnetic pole part 3. Furthermore, fixing protrusions 6 and 7 are provided on both end faces of the fixed yoke 1, and front plates 8 and 7 are respectively provided.
The fixed yoke 1 is inserted into the mounting hole of the back plate 9 and fixed. The front plate 8 and the rear plate 9 are connected by side frames 10 and 10' located on both sides to form a housing. Both ends of the magnetic path plate 12 are inserted into the guide grooves 11, 11' of the side frames 10, 10', and the magnetic path plate 12 comes into contact with the back plate 9 and is fixed with screws or the like. Both ends of the coil 4 wound around the coil bobbin 5 are connected to connection terminals of printed circuit boards 13, 13' disposed on the top and bottom sides, and current is supplied thereto. The protrusions 14 of the coil bobbin 5 are fitted into the notched grooves of the printed circuit boards 13, 13', so that the digit pitch spacing is maintained accurately. The printed circuit boards 13, 13' to which the coil bobbin 5 is fixed are screwed to the side frames 10, 10'. The fixed yokes 1 are arranged facing each other in a staggered manner vertically with the magnetic path plate 12 as a boundary, and the pitch interval in the girder direction is maintained at 3 mm. By arranging them in a staggered manner, a small pitch interval can be obtained in the direction of the girder. On the front surface of the front plate 8, a comb-shaped stopper plate 18 is provided with a stopper claw 17 that comes into contact with the stopper protrusion 16 of the ratchet wheel 15 to stop the rotation of the ratchet wheel 15, and a guide for the tip end claw of the selection lever 19. A selection lever guide plate 20 is installed, and the tip claw of the selection lever 19 is connected to the selection lever guide plate 20.
It reciprocates while being guided by the grooves while accurately maintaining the pitch spacing in the digit direction. The magnetic path plate 12 is formed with cutout grooves for arranging the selection levers 19. The selection lever 19 is rotatably supported by a support shaft 21, and its distal end claw engages with the ratchet wheel 15 to restrict rotation of the ratchet wheel 15. The main body side swinging portion is screw-bent so as to be orthogonal to the plane of the tip claw portion, and is disposed oppositely within the concavely formed magnetic pole portion 3 of the fixed yoke 1. Permanent magnets 2 on both sides of the swinging part
2 and 23 are fixed with adhesive. Each permanent magnet 2
2 and 23 are fixed yoke 1, back plate 9, magnetic path plate 12,
The polarities are fixed, for example, as shown in FIG. 5 so that the magnetic fluxes flowing through the selection lever 19 are in opposite directions. The swinging portion of the selection lever 19 reciprocates about the support shaft 21 within the magnetic pole portion 3 of the fixed yoke 1, so that the tip claw portion engages with the ratchet wheel 15.

The fixed yoke 1, the back plate 9, the magnetic path plate 12, and the selection lever 19 are made of magnetic material such as low carbon steel. The coil bobbin 5 and the like are made of non-magnetic material such as copper alloy or plastic. With this configuration, multiple selection levers 1
The magnetic flux flowing through 9, 19, ... is all connected to a single magnetic path plate 1.
2.

The operation of the type selection mechanism having the above configuration will be explained as follows.

FIG. 1 shows a standby state before type selection, in which the tip claw portion of the selection lever 19 is detached from the ratchet wheel 15.

When the rotating shaft 24 is rotated in the direction of arrow Y by a motor (not shown) or the like, the ratchet wheel 15 and the type wheel 26, which are frictionally engaged by the spring 25, rotate in conjunction with each other, and the type 27 to be printed is printed. When I arrived at the position,
A current is passed through a coil 4 installed in the magnetic core part 2 of the fixed yoke 1, and a magnetic field is generated in the magnetic pole part 3. The magnetomotive force of the coil 4 is generated by the magnetic field of the magnetic pole part 3
9 act on the permanent magnets 22 and 23 bonded to the swinging part 9 to move the swinging part in the direction of the arrow X shown in FIG. . The tip pawl of the selection lever 19 and the pawl wheel 15
The rotation of the ratchet wheel 15 and the type wheel 26 is stopped by this engagement. The swinging part of the selection lever 19 is a permanent magnet 2
3, the permanent magnet 23 is held in magnetic contact with one pole side of the magnetic pole portion 3 of the fixed yoke 1, and even when the coil 4 is de-energized, the selection lever 19 remains in the ratchet wheel 15. remains engaged. The number of type wheels 26, ratchet wheels 15, and selection levers 19 are arranged in a number corresponding to the number of displayed digits, and by repeating the above operation for each digit, all the type characters 27 are aligned at the printing position. . When the arrangement of the printed characters is completed, the hammer 28 places the printed characters 2 on the recording paper 29.
Stamp 7.

When printing is completed, the rotating shaft 24 rotates in a direction opposite to the direction of the arrow Y, and the ratchet wheel 15 and type wheel 26 similarly rotate in conjunction with each other. At this time, the tip claw of the selection lever 19 that was engaged with the ratchet wheel 15 is kicked down by the claw of the ratchet wheel 15, and the swinging part moves within the magnetic pole part 3 in the opposite direction to the direction of the arrow X. and return to the original standby state. In the standby state, the permanent magnet 22 of the swinging portion is held in magnetic contact with the other pole side of the magnetic pole portion 3 of the fixed yoke 1. The rotating shaft 24, ratchet wheel 15, and type wheel 26 continue to rotate until they return to their original standby positions, and stop when the stopper protrusion 16 of the ratchet wheel 15 and the stopper pawl 17 of the stopper plate 18 come into contact.

In addition to the above method, the selection lever 19 can be returned to the standby state by energizing the coil in the opposite direction to generate a magnetic field in the opposite direction.

As explained in detail above, according to the type selection mechanism of the present invention, the selection lever is self-held in the standby state and the printing position, so that power consumption can be reduced.
Furthermore, since the selection lever directly locks the ratchet wheel, the number of parts is reduced and the structure is simplified. In addition, since a magnetic path is constituted by the plate body with the support shaft that supports the selection lever, the selection lever, the permanent magnet, the magnetic material of the electromagnet, and the back plate, the generated magnetism can be effectively used as driving force. Can be done. Further, by configuring the magnetic flux flowing through the plurality of selection levers to flow into a single plate member, the overall configuration of the magnetic circuit can be simplified and assembly of the device can be made very convenient. Therefore, it is an effective type selection mechanism for printers in electronic devices that require miniaturization such as calculators with low power consumption.

[Brief explanation of the drawing]

FIG. 1 is a vertical sectional view of a type selection mechanism showing one embodiment of the present invention. FIG. 2 is a plan view including a partial cross section taken along the line AA of the type selection mechanism in FIG. Figure 3 shows B- of the type selection mechanism in Figure 1.
FIG. Figure 4 is the first
FIG. 3 is a left side view including a broken surface of a main part of the type selection mechanism in the figure. FIG. 5 is an enlarged view of the main part showing the control portion of the type selection mechanism in FIG. 1. DESCRIPTION OF SYMBOLS 1... Fixed yoke, 2... Magnetic core part, 3... Magnetic pole part, 4... Coil, 5... Coil bobbin, 15...
...Rawl wheel, 19...Selection lever, 21...Support shaft,
22, 23...Permanent magnet, 26...Type wheel, 27
...Print.

Claims (1)

[Scope of utility model registration request] A plurality of type wheels arranged with type characters, a plurality of ratchet wheels interlocking with the type wheels, and a support shaft formed as a part of a single magnetic plate are rotatably supported, and the tip claw portion is A plurality of selection levers made of a magnetic material that engage with the ratchet wheel, a plurality of magnets provided on the swinging portion of the selection levers, and a magnetic field generated at the position of the magnets to move the selection levers to the support shaft. a plurality of magnetic bodies that are rotated about a rotation axis; a coil wound around the magnetic bodies; and a back plate made of a magnetic material that contacts the magnetic bodies and the back surface of the single magnetic plate; A magnetic path is formed by one magnetic plate, the selection lever, the magnet, the magnetic body, and the back plate, and the magnetic flux flowing through the plurality of selection levers flows into the single magnetic plate. A type selection mechanism featuring: