JPS59111876A - Typewriter - Google Patents

Abstract

PURPOSE:To operate a releasing lever with an extremely small operating force and to facilitate releasing a blank form, by a method wherein a spring for maintaining an interlocked relationship of a link lever and a releasing lever is made to be one having a relatively weak spring force. CONSTITUTION:A spring 19 having a small force is used as a spring provided for the link lever 17, the spring force is so set that a pin 16b can easily ride over a cam 18a. When the position of a pin 20 and that of a notched part 17a are appropriately selected, the pin 20 comes into contact with an upper edge 17b proximate to the notched part 17a in the beginning of operation of the releasing lever 16, thereby preventing the lever 17 from being rotated counterclockwise. When the lever 16 is further rotated counterclockwise and the pin 16b approaches to a condition of riding over the cam 18a, the lever 17 tends to be rotated counterclockwise, and since the pin 20 is located at a position corresponding to the notched part 17a, the link lever 17 is permitted to rotate counterclockwise. Since the force of the spring 19 is weak, movement at this moment proceeds extremely easily, and a blank form can be easily released.

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, a typewriter has more than just a keyboard.
The number of various levers has gradually increased, and their operation has become extremely complicated. Furthermore, the same applies to levers related to releasing and setting paper, and there are two types of levers: a lever for releasing rollers for transporting paper, and a lever for releasing paper pressing rollers for bringing 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 la and lb, and a pulse motor (not shown) is connected to the frame. , rotated by a driving force.

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

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

A paper guide 8 is provided between the platen 2 and the feed roller 3.
is located on the platen 2 side through an opening (not shown) formed in this paper guide 8, and the paper guide 8 is inserted into the platen 2 side.
is in contact with. 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 pail shaft 11 is horizontally suspended in parallel with the platen 2 on the front side of the platen 20, and a plurality of paper pressing rollers 10 in contact with the platen 2 are rotatably supported on this shaft.

The left and right ends of the pail shaft 11 are respectively fixed to the pail arm 12, and the lower ends of the pail arm 12 are protruded from the side plates 1a, lb of the frame with projecting pieces 1c, l.
c through a shaft 1d so as to be rotatable. A torsion coil spring 13 is wound between the pale arm 12 and the protrusion IC, and the pale arm 12 has two
can be located 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 is passed between the feed roller 3 and the platen 2.
It is possible to pass between.

For example, the section below the rear end of the feed lever 4 is D.
A letter-shaped release shaft 14 is rotatably suspended horizontally, and when the release shaft 14 is rotated counterclockwise as shown by the arrow in FIG. 1, the arc-shaped side surface of the release shaft 14 becomes a feed lever. 4, the feed lever 4 is rotated counterclockwise in FIG. Leave.

One end of the release shaft 14 is fitted through a D-shaped through hole 15a formed at one end of the lever 15.
A pin 151) projecting from this lever 15 is fitted into a cam hole 16a formed in the release lever 16.

The release lever 16 is rotatably supported by a pin 1 (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 12 protruding from the outer surface of the lower end of the pale arm 12, and a pin U protruding from the side plate 1b is connected to the middle of the link lever 17. A spring 18 is stretched between them, giving the link lever 17 the ability to rotate in the open direction in the figure.

A serrated cam 1 is provided on the lower surface of the free end side of the link lever 17.
8a is formed, and this cam i8a is engaged with a pin 16b protruding from the side surface of the curry release lever 16.

Next, we will explain the third part regarding the operation of the conventional example configured as above.
This will be explained with reference to FIGS.

In the state before paper is set, as shown in FIG. 3, the back side of the cam 18a of the link lever 17 is the release lever 16
The pale arm 12 is in a first stable state due to its positional relationship with the torsion coil spring 13.
That is, the roller 10 is in contact with the platen 2.

The mater release lever 16 is in a state where the pin 15b is located at the lowest end of the cam hole 16a, the arc-shaped surface of the release shaft 14 having a D-shaped cross section faces upward, and the near side of the feed lever 4 is The feed roller 3 is raised due to the tensile force of the spring 7 and 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. Rotate counterclockwise,
Roller 10 leaves 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.

From this state, when the release lever 16 is further rotated counterclockwise in the figure, the release lever 16 is rotated as shown in FIG.
The G pin 16b begins to ride over the cam 18a, and the link lever 17 is rotated slightly counterclockwise about the pin 12a.

At the same time, as the release lever 160 rotates, the pin 151) of the lever 15 moves into the cam hole 16a formed in a reverse dogleg shape.
The lever 15 begins to rotate counterclockwise in the figure, and the release shaft 14 having a D-shaped cross section is also rotated counterclockwise, and its arcuate peripheral surface becomes the feed l/ Push up the lower surface of the bar 4 on 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. Then, the release lever 16 is rotated counterclockwise to the maximum extent as shown in FIG.
When the pin 16b reaches the outer end of the cam 18a, the pin 16b is fitted to the outside of the cam 18a, and this state is maintained.

This state is a 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 1
If the spring force of the release lever 8 is strong, an extremely large force is required to operate the release lever 16, making the operation extremely inconvenient.

OBJECTS The present invention has been made in order to eliminate the above-mentioned drawbacks of the conventional typewriter, and an object of the present invention is to provide a typewriter configured so that the release lever can be operated extremely easily.

EXAMPLE 1 The present invention will be described in detail based on Example 1 shown in the drawings.

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 a much weaker force than the spring 18 is used as the spring 1 nong provided on the link lever 17.

The strength of the spring 19 is such that the pin 16b can easily be attached to the cam 1.
It is strong enough to overcome 8a.

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

If such a structure is adopted, the position of the pin 2o and the notch 1
If the position of 7a is selected correctly, at the initial stage of operation of the release lever 16, the pin 2o contacts the upper edge 17b of the link lever 17 near the notch 17a, as shown in FIG. 7, and the link lever 17 moves counterclockwise in the figure. rotation can be prevented. Therefore, the spring force of the spring 19 does not need to be so large.

Further, as shown in FIG. 8, when the release lever 16 is further rotated counterclockwise in the figure and the pin 161 approaches the state where it passes over the cam 18a, the link lever 17
However, since the pin 20 is located at a position corresponding to the notch 17a, the rotation of the link lever 4 in the counterclockwise direction is allowed. Furthermore, since the sedge 1 nong 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 the present invention, the engagement relationship between the cam provided on the link lever that interlocks with the release lever and rotates the pale arm, and the pin provided on the release lever side. A relatively weak spring is used to maintain the link lever, and a pin is provided on the frame side of the device to restrict the rotation of the link lever.This allows the release lever to be operated with an extremely small operating force, releasing the paper. You can easily get a typewriter.

[Brief explanation of the drawing]

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...Flann 3...Feed roller 4...Feed lever 8...Paper guide 11...Pail shaft 12...Pail arm 13...Torsion coil spring 14...
Release shaft 15...Lever 1699. Release lever 1719. Link lever 18...Spring 18a...Cam. Patent applicant Canon Co., Ltd.

Claims (1)

[Claims] A typewriter comprising: a feed roller that can come into contact with and be separated from the platen in conjunction with a release lever; and a pail arm that has a roller that can come into contact with and be separated from the platen through a link lever that is interlocked with the release lever. The pin that restricts the rotation of the lever is set up using a spring ring that maintains the interlocking relationship between the link lever and release lever, and has a relatively weak spring force that allows the release lever to be easily operated. Typewriter.