JP2629827B2 - Type ring selection mechanism - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a type wheel selecting mechanism for a small printer or the like.

[Conventional technology]

Conventionally, as described in JP-B-59-13985, a selection claw (latch plate) is urged by a spring to be in a selected state, and the urge is attracted to a magnet via an iron core. Was supported by a movable piece.

At the time of selection, the coil generates a magnetic field opposite to that of the magnet, cancels out the attraction force of the movable piece, and engages the selection claw with the ratchet of the print ring (character ring) by the urging force of the spring.

When retracting the selection claw out of the rotation trajectory of the reset tooth of the type ring, the selection claw is controlled by a cam and the spring is compressed.

[Problems to be solved by the invention]

Therefore, in the method described in JP-B-59-13985,
Each of the girders requires a movable piece and a spring, increasing the number of parts, and has been a barrier to downsizing and lowering the cost of the selection mechanism.

Furthermore, high precision is required for springs,
High production technology was required to ensure quality, and this was a barrier to mass production.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned drawbacks and to provide a type-ring selecting mechanism that is low-cost, small-sized, and easily mass-produced.

[Means for solving the problem]

In order to solve the above problems, a type wheel selecting mechanism according to the present invention includes a type wheel having a ratchet corresponding to the type and a reset tooth protruding from a rotation locus of the ratchet on a side surface, and a type wheel frictionally engaged with the type wheel. , A selection claw having a claw that engages with a ratchet of the type ring to select a type, a selection claw shaft rotatably supporting and supporting the selection claw, and a selection claw. A trigger mechanism for rotating the ratchet of the print ring to engage with the ratchet of the type ring, and a reset mechanism for releasing the engagement between the selection claw and the ratchet and returning the selection claw to a standby state. When the claw is retracted to the outside of the rotation locus of the reset tooth, the selection claw shaft moves.

[Action]

According to the above configuration of the present invention, when the selection claw shaft that rotatably supports the selection claw is movably disposed, and the claw portion of the selection claw is retracted outside the rotation locus of the reset tooth, the selection claw shaft is Is moved, the displacement of the claw portion of the selection claw is obtained by combining the displacement of the selection claw rotating the selection claw shaft and the displacement of the selection claw shaft.

〔Example〕

 The present invention will be described with reference to examples.

FIG. 1 is a cross-sectional view showing one embodiment of the present invention, and shows a standby state of a selection claw.

The selection claw 1 is fitted on the selection claw shaft 2 and is rotatable. The foot 1a of the selection claw 1 is
It has a structure that penetrates a hollow portion 3a provided in the trigger coil 3 inside and also serves as an iron core. Tip 1b of foot of selection nail 1
Are attracted to the permanent magnet 4 via the pole plate 5 and rotation is restricted.

Reference numeral 6 denotes a reset lever, which is engaged with the head 1c of the selection claw 1 and is pressed by a reset lever spring 17 against a reset cam 7 which makes one rotation during one printing line, and is rotatable around a reset lever shaft 8. Has become.

The selection claw shaft 2 is movable in the direction of arrow A, is supported by a bearing having an oval hole (not shown), is urged in the direction of arrow B by the selection claw shaft spring 9, and is positioned. .

The print ring 10 has a ratchet 1 corresponding to each print 10a.
0b and a reset tooth 10c protruding from the rotation locus of the ratchet 10b. A type ring spring 11 is attached to the type ring 10, and a tip 11c of the type ring spring 11 is provided on a type wheel axle 12 by a spring force.
, And can rotate integrally with the type wheel set 12.
At this time, the tip 1a of the selection claw 1 is
Although it is out of the rotation locus of b, it is in the rotation locus of the reset tooth 10c.

 FIG. 2 shows a state of selection start.

When the reset cam 7 starts rotating in the direction of the arrow, the reset lever 6 rotates in the direction of the arrow c by the protrusion 7a of the cam. Then, the hook 6a of the reset lever 6 urges the head 1c of the selection claw 1 in the direction of arrow D, and moves the selection claw shaft 2 in the direction of arrow A against the spring force of the selection claw shaft spring 9. Let me know. At this time, the selection 1b of the foot of the selection claw 1 slightly moves in the direction of arrow E while being attracted to the electrode plate 5.

In this state, the selection 1d of the selection claw 1, which is the claw portion, is outside the rotation locus of the reset tooth 10c of the type wheel 10, and the type wheel axle 12
Is rotated in the direction of arrow F, the reset tooth 10c can be located below the tip 1d of the selection claw 1.

FIG. 3 is a diagram showing a state where characters can be selected, and FIG.
When the reset cam 7 further rotates from the selection start state shown in the drawing, the reset river 6 rotates in the direction of arrow A by the selectable portion 7b, and the selection claw shaft 2 and the selection claw 1 are moved by the selection claw shaft spring 9 by the selection claw shaft spring 9. Returning to the same position as in FIG. 1, the hook 6a of the reset river 6 and the head 1c of the selection claw 1 are separated from each other, and a gap of x is formed.

FIG. 4 is a view showing a selection state, and is shown in FIG.
When the character wheel axle 12 further rotates in the direction of arrow F from the state in which characters can be selected, the ratchet portion 10b of the character wheel 10 becomes a position facing the tip 1a of the selection claw 1. Here, when applied to the trigger coil 3, the tip 1b of the foot of the selection claw 1 is magnetized to the S pole. Since the permanent magnet 4 has the polarity as shown in FIG. 1, a repulsive force is generated between the pole plate 5 and the tip 1b of the foot of the selection claw 1, and the selection claw 1 is moved in the direction of arrow G. Rotate to
Jump into the ratchet 10b of the print wheel 10 and stop the rotation of the print wheel 10. The type wheel axle 12 further rotates. At this time, the type wheel axle 11 escapes from the V groove 12a of the type wheel axle 12 and rises up to the outer shape portion 12b.

FIG. 5 is a diagram showing a printing state. Selected type
Reference numeral 10d denotes a printing roller 15 supported by a printing roller receiver 14 fixed to the printing shaft 13, and performs printing by pressing.

 FIG. 6 is a view showing a return process of the type wheel 10.

The reset lever 6 is rotated in the direction of arrow C by the selection claw reset portion 7c of the reset cam 7, the hook portion 6a hooks the head 1a of the selection claw 1, and the tip 1d of the selection claw 1 is moved by the arrow D. , And escapes from the rotation locus of the ratchet 10b of the type ring 10.

Then, the tip 1b of the foot is attracted to the permanent magnet 4 via the pole plate 5, and the selection claw 1 is in a standby state.

Further, when the print wheel 12 rotates, the print wheel 10 rotates in the same direction due to the frictional force between the print wheel spring 11 and the print wheel axle 12, and the reset tooth 10 c contacts the tip 1 d of the selection claw 1. Touch, the rotation stops, and the type wheel 10 is reset.

In this state, the type wheel set 12 further rotates, but the type wheel set 12
11 and the print wheel shaft 12 slide, and the print wheel 10 becomes the reset tooth 10c.
However, it does not rotate only by being pressed against the tip 1d of the selection claw 1.

The print ring spring 11 is engaged with the V groove 12a, and one printing line is completed.

FIG. 7 is a perspective view of one embodiment of the present invention. In the trigger case 16, the bearing 16a of the selection claw shaft 2 and the bearing 16b of the reset lever shaft 8 are integrated.
The bearing portion 16a has an elongated hole shape, and has a structure in which the selection claw shaft 2 is movable.

Further, by adding functions such as a reset lever shaft, a bearing of a selection claw shaft, and a hook portion of a selection claw shaft spring to the trigger case, the functions are easily integrated, the selection mechanism is unitized, and the printer body is assembled. There is another effect that is significantly easier.

In the embodiment, the reset lever has a function of moving the selection claw shaft. However, the effect of the present invention is not changed even if the reset lever is operated by another independent mechanism.

〔The invention's effect〕

As described above, according to the present invention, a type wheel having a ratchet corresponding to the type and a reset tooth protruding from a rotation locus of the ratchet on a side surface, and a type wheel axle frictionally engaging with the type wheel to rotate the type wheel And a selection claw that includes a claw portion that engages with a ratchet of the type ring to select a type, a selection claw shaft that rotatably supports and moves the selection claw, and that rotates the selection claw. A trigger mechanism for engaging the ratchet of the type ring, and a reset mechanism for releasing the engagement between the selection claw and the ratchet and returning the selection claw to a standby state,
The reset mechanism is configured such that when the claw portion of the selection claw is retracted to the outside of the rotation trajectory of the reset tooth, the displacement amount of the claw portion of the selection claw is changed by rotating the selection claw shaft. Since the displacement amount and the displacement amount due to the movement of the selection claw shaft are combined, the displacement amount of the selection claw that rotates the selection claw shaft that the trigger mechanism rotates with respect to the desired displacement amount of the claw portion is small. Therefore, the rotation is stable, the reliability of selection by the trigger mechanism is greatly improved, and a printer free from erroneous selection can be provided.

Also, since the amount of rotation of the selection claw at the time of selection is small,
The function can be improved by increasing the printing speed by shortening the selection time. Furthermore, the simple mechanism allows the practical effect of the present invention to be extremely large, such as reduction in size and cost as well as improvement in reliability.

[Brief description of the drawings]

 1 to 6 are sectional views showing an embodiment of the present invention. FIG. 1 is a sectional view showing a standby state. FIG. 2 is a sectional view showing a selection start state. FIG. 3 is a sectional view showing a type selectable state. FIG. 4 is a sectional view showing a selected state. FIG. 5 is a sectional view showing a printing state. FIG. 6 is a sectional view showing a return stroke. FIG. 7 is a perspective view showing an embodiment of the present invention. 1 ... Selection claw 2 ... Selection claw shaft 3 ... Trigger coil 4 ... Permanent magnet 5 ... Electrode plate 6 ... Reset lever 7 ... Reset cam 8 ... Reset lever shaft 9 ... Selection claw shaft spring 10 … Type wheel 10a …… Type 10b …… Ratchet tooth 10c …… Reset tooth 10d …… Selected type 11 …… Type ring spring 12 …… Type wheel axle 13 …… Print shaft 14 …… Print roller receiver 15 …… Printing roller 16… Trigger case 16 a… Bearing part of the selection claw shaft 16 b… Bearing part of the reset lever shaft 17… Reset lever spring

Claims (1)

(57) [Claims] 1. A printer in which selection and resetting of a character ring having a character on the outer periphery is performed by rotation in one direction, wherein a ratchet corresponding to the character and a reset tooth protruding from a rotation locus of the ratchet are provided on a side surface. A type wheel provided with: a type wheel shaft that frictionally engages with the type wheel to rotate the type wheel; a selection claw that includes a claw portion that engages with the ratchet of the type ring to select the type; A selection claw shaft rotatably supporting and supporting a claw; a trigger mechanism for rotating the selection claw to engage with the ratchet of the type ring; and a connection between the selection claw and the ratchet. A reset mechanism for canceling the engagement and returning the selection claw to a standby state, wherein the reset mechanism is configured to perform the selection when the claw portion of the selection claw is retracted to the outside of the rotation locus of the reset tooth. A type ring selection mechanism characterized in that the claw shaft moves.