JPH047312B2 - - Google Patents

Description

TECHNICAL FIELD The present invention relates to a typewriter, and more particularly to a typewriter with an improved paper feeding device.

BACKGROUND ART In recent years, typewriters have become more sophisticated and sophisticated, and as a result, the number of operating points has increased, requiring operators to perform a variety of operations.

In other words, typewriters have not only a keyboard but also various levers, and the operation thereof has become extremely complicated. Furthermore, the same applies to the levers used to release and set the paper, and there are two types of levers: a paper conveyance roller release lever and a lever that releases the paper presser roller that brings the paper into close contact with the platen.

Recently, some typewriters are equipped with a paper feeding device that performs these two functions with a single lever.

An example of a conventional typewriter having such a structure is shown in FIG.

In FIG. 1, the reference numeral 1 indicates a frame shaped like a frame, and a platen 2 is rotatably supported between the left and right side plates 1a and 1b, and a pulse motor (not shown) is connected to the frame. Rotated by driving force.

A feed roller 3 is arranged below the platen 2 so as to be parallel in the front and back, and is rotatably supported by a feed arm 5 fixed to a feed lever 4.

A feed lever 4 is rotatably supported on a shaft 6a of a bracket 6 fixed to the frame 1, and the feed rollers 3 are pressed against the platen 2 by the tensile force of a spring 7.

A paper guide 8 is located between the platen 2 and the feed roller 3, and is inserted into the platen 2 through an opening (not shown) formed in the paper guide 8, and is in contact with the platen 2. . As a result, the printing paper guided along the paper guide 8 between the platen 2 and the feed roller 3 is fed out at a predetermined pitch as the platen 2 rotates.

A bail shaft 11 is horizontally suspended on the front side of the platen 2 in parallel with the platen 2, and a plurality of paper pressing rollers 10 in contact with the platen 2 are rotatably supported on the bail shaft 11.

The left and right ends of the bail shaft 11 are each fixed to a bail arm 12, and the lower end of the bail arm 12 is rotatable via a shaft 1d on protrusions 1c, 1c protruding from the side plates 1a, 1b of the frame. The bearing is mounted on the shaft. And this bail arm 1
A torsion coil spring 13 is wound between the bail arm 2 and the protruding piece 1c, so that the bail arm 12 can be positioned in two stable states.

One stable state is a state in which the roller 10 is in close contact with the platen 2, and the other stable state is a state in which the roller 10 is separated from the platen and the printing paper 9 can be passed between the feed roller 3 and the platen 2. .

A release shaft 14 having, for example, a D-shaped cross section is rotatably suspended below the rear end of the feed lever 4, and the release shaft 14 is rotated counterclockwise as shown by the arrow in FIG. When the release shaft 14 is rotated, the arcuate side surface of the release shaft 14 contacts the lower edge of the feed lever 4, and the feed lever 4 is rotated counterclockwise in FIG. 1 about the shaft 6a against the tensile force of the spring 7, and the feed roller 3, 3 descends and leaves the platen 2.

One end of the release shaft 14 is fitted through a D-shaped through hole 15a formed at one end of a lever 15, and a pin 15b protruding from this lever 15 is fitted into a cam hole formed at the release lever 16. 1
6a. The release lever 16 is rotatably supported on a pin 1f protruding from the outer surface of the side plate 1b.

On the other hand, one end of a link lever 17 is rotatably supported on a pin 12a protruding from the outer surface of the lower end of the bail arm 12, and between the middle of the link lever 17 and the pin protruding from the side plate 1b. A spring 18 is tensioned on the link lever 17.
A clockwise rotational behavior is given in the figure.

A serrated cam 18a is formed on the lower surface of the free end side of the link lever 17.
is the pin 1 protruding from the side of the release lever 16.
6b.

Next, the operation of the conventional example configured as above will be explained with reference to FIGS. 3 to 6.

In the state before paper is set, the back side of the cam 18a of the link lever 17 is engaged with the pin 16b of the release lever 16, as shown in FIG. causes the first stable state, i.e. the roller 10
is in contact with platen 2.

Further, the release lever 16 is in a state in which the pin 15b is located at the lowest end of the cam hole 16a, the arcuate surface of the release shaft 14 having a D-shaped cross section faces upward, and the front side of the feed lever 4 has a spring. 7 and the feed roller 3 is in contact with the platen 2.

In this state, when the release lever 16 is rotated counterclockwise around the pin 1d in FIG. 3, the link lever 17 is pulled to the right in FIG. 3 by the pin 16b, and the bail arm 12 is rotated around the pin 1d. By rotating counterclockwise, the roller 10 is separated from the platen 2. The function of the torsion coil spring 13 maintains the second stable state in which the roller 10 is separated from the platen 2.

This state is the state shown in FIG.

When the release lever 16 is further rotated counterclockwise in the figure from this state, the pin 16b of the release lever 16 begins to overcome the cam 18a as shown in FIG. 5, and the link lever 17 moves slightly counterclockwise around the pin 12a. rotated in the direction.

At the same time, as the release lever 16 rotates, the pin 15b of the lever 15 begins to advance near the outer end of the cam hole 16a formed in the shape of an inverted dogleg, and the lever 15 rotates counterclockwise in the figure. Initially, the release shaft 14 having a D-shaped cross section is also rotated counterclockwise, and its arc-shaped peripheral surface is connected to the feed lever 4.
Push up the bottom surface of the spring 7 side. As a result, the feed lever 4 is rotated counterclockwise about the pin 6a in FIGS. 1 and 2 against the tensile force of the spring 7, and the feed roller 3 is separated from the platen 2. This state is shown in FIGS. 5 and 6. and release lever 16
is rotated counterclockwise to the maximum extent as shown in FIG. 6, and when the pin 15b reaches the outer end of the cam hole 16a, the pin 16b fits into the outer side of the cam 18a.
This state is maintained.

This state is the state in which paper release can be performed.

However, if the conventional structure as described above is adopted, the force of the spring 18 must be extremely large in order to prevent the pin 16b from overcoming the cam 18a when changing from the state shown in FIG. 3 to the state shown in FIG. It is necessary to do so.

Further, between the state shown in FIG. 4 and the state shown in FIG. 6, when the pin 16b gets over the cam 18a, the spring force of the spring 18 is strong, or an extremely large force is required to operate the release lever 16. , operation becomes extremely inconvenient.

Purpose The present invention was made in order to eliminate the above-mentioned drawbacks of the conventional type, and an object of the present invention is to provide a typewriter whose release lever can be operated extremely easily.

Means for Solving the Problems In order to achieve the above objects, the present invention has the following features:
a platen, a paper pressing roller provided so as to be movable toward and away from the platen, a feed roller provided so as to be movable toward and away from the platen, a bail arm holding the paper pressing roller, and a bail arm holding the feed roller. a release lever for moving the paper pressing roller and the feed roller toward and away from the platen; and a rotation of the release lever for moving the paper pressing roller and the feed roller toward and away from the platen. a typewriter comprising a link lever that rotates the bail arm and the feed arm by a motion, wherein the release lever and the link lever are in a first engaged state and a second engaged state. a regulating portion for regulating the rotation of the link lever in the direction of releasing the first engaged state in the first engaged state; The link lever is characterized by having a notch provided in the link lever that allows the link lever to rotate when the link lever moves to the engaged state.

Effects With the above-described structure of the present invention, it is possible to obtain a typewriter in which the release lever can be operated with an extremely small operating force and which can easily press and release paper.

Embodiments Hereinafter, details of the present invention will be explained based on embodiments shown in the drawings.

The embodiment described below includes a feed roller that comes into contact with and moves away from the platen in conjunction with a release lever, and a bail arm that has a roller that comes into contact with and moves away from the platen through a link lever that moves in conjunction with the release lever. In the typewriter, a pin is provided to restrict the rotation of the link lever, and a spring with a relatively weak spring force that allows the release lever to be easily operated is used as a spring to maintain the interlocking relationship between the link lever and the release lever. It's a typewriter.

7 and 8 illustrate one embodiment of the present invention, and the same parts in the figures as in FIGS. 1 to 6 are given the same reference numerals, and the explanation thereof will be omitted.

In this embodiment, a spring 19 having much weaker force than the spring 18 is used as the spring provided on the link lever 17.
The strength of this spring 19 is such that the pin 16b can easily overcome the cam 18a.

On the other hand, above the link lever 17, the side plate 1
A pin 20 is provided protruding from b. A notch 17a is formed on the upper surface of the link lever 17.

If such a structure is adopted and the position of the pin 20 and the position of the notch 17a are selected correctly, the pin 20 will be in the seventh position at the initial stage of operation of the release lever 16.
As shown in the figure, the notch 17a of the link lever 17
The link lever 17 can be prevented from rotating counterclockwise in the drawing by contacting the upper edge 17b near the upper edge 17b. Therefore, a very large spring force of the spring 19 is not required.

In addition, as shown in FIG. 8, the release lever 16
is further rotated counterclockwise in the figure, and when the pin 16b approaches a state where it passes over the cam 18a, the link lever 17 tries to rotate counterclockwise in the figure around the pin 12a, but the pin 20 17a
Since the link lever is located in a position corresponding to that of the link lever, counterclockwise rotation of the link lever can be permitted. Further, since the spring 19 is a weak spring, the operation at this time can be performed extremely easily, and the sheet can be released easily.

Effects As is clear from the above explanation, according to this embodiment, a pin is provided on the frame side of the device to restrict the rotation of the link lever that rotates the bail arm in conjunction with the release lever. In addition, the link lever has a notch that allows the link lever to rotate when the pin provided on the release lever side passes over the cam provided on the link lever, so it can be operated with an extremely small operating force. It is possible to obtain a typewriter in which a release lever can be operated and paper can be easily released.

As is clear from the above description, according to the present invention, it is possible to obtain a typewriter in which the release lever can be operated with an extremely small operating force, and which can also easily press and release paper.

[Brief explanation of drawings]

1 and 2 are perspective views and side views of main parts to explain the conventional structure, FIGS. 3 to 6 are side views to explain the operation, and FIGS. 7 and 8 are views of the part of the present invention. It is a side view explaining the structure and operation of an example. 1... Frame, 2... Platen, 3... Feed roller, 4... Feed lever, 8... Paper guide, 11... Bail shaft, 12... Bail arm, 13... Torsion coil spring, 14...
Release shaft, 15...Lever, 16...Release lever, 17...Link lever, 18...
Spring, 18a...cam.

Claims (1)

[Scope of Claims] 1. A platen, a paper pressing roller provided so as to be movable toward and away from the platen, and a feed roller disposed so as to be movable toward and away from the platen,
a bail arm that holds the paper pressing roller;
a feed arm for holding the feed roller; a release lever for moving the paper press roller and the feed roller toward and away from the platen; and a release lever for moving the paper press roller and the feed roller toward and away from the platen. A typewriter including a link lever that rotates the bail arm and the feed arm by rotation of a release lever, wherein the release lever and the link lever are in a first engaged state and a second engaged state. a regulating portion for restricting the rotation of the link lever in the direction of releasing the first engaged state in the first engaged state; and the first engaged state. A typewriter comprising: a notch provided in the link lever that allows rotation of the link lever when the link lever moves from the first engagement state to the second engagement state.