JPH10309855A - Ink ribbon cassette - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pressing mechanism that imparts a tension to an ink ribbon in a simple structure. SOLUTION: A box-shaped cassette body which is opened upwardly is comprised of a bottom piece 2 and side pieces 3, 4. A gap is formed between an inner wall of one side piece 3 and a tip section of the other side piece 4 at a portion where the side pieces 3, 4 are crossed with each other to provide a slit-shaped ribbon outlet 6. A piece housing hole 17 which is opened toward an inner wall of the side piece 3 is formed on a bottom face of a recess section 16 which is formed on the top face in the tip section of the side piece 4. Apiece 11, which consists of a plate piece 18 having a knob 8 on the top thereof and a ribbon urging piece 19 protruding downwardly horn the tip of the plate piece of which lateral width L is slightly greater than an inner width of the piece housing hole 17, is formed. The ribbon urging piece 19 is provided to be opposite to the inner wall of the side piece 3 in the piece housing hole and is housed in the cassette body so as not to contact the bottom piece 2. The lower face of the plate piece is loaded on the bottom face of the recessed 16. A spring 12 is inserted into a space between the ribbon urging piece and the innermost face of the piece housing hole 17 such that the spring contacts both of them.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink ribbon cassette having an improved ribbon pressing mechanism for applying tension to an ink ribbon.

[0002]

2. Description of the Related Art Conventionally, an ink ribbon cassette is provided with a ribbon pressing mechanism for carrying out an ink ribbon while maintaining a constant tension, and those shown in FIGS. 3 and 4 are known. This ribbon pressing mechanism includes a cassette body 1
Is formed in the shape of a box having an opening at the top with the bottom piece 2 and the side pieces 3, 4 and 5, and at the portions where the side pieces 3 and 4 are orthogonal to each other, the inner wall of one side piece 3 and the tip of the other side piece 4 A slit-shaped ribbon outlet 6 is provided with a gap formed between the ribbon outlet 6 and the portion. And
A piece storage hole 7 is formed by recessing the upper surface of the tip of the side piece 4 and opening toward the inner wall of the side piece 3, while a plate piece 9 having a knob 8 formed on the upper surface, A piece 11 consisting of a ribbon pressing piece 10 hanging downward from the tip is formed, the ribbon pressing piece 10 of the piece 11 is opposed to the inner wall of the side piece 3 in the piece storing hole 7, and the bottom of the piece 11 is The knob 8 is pulled out of the frame receiving hole 7 and a spring 12 is inserted between the ribbon pressing piece 10 and the inner surface of the frame receiving hole 7 so as to be in contact with both. .

[0003] However, such a ribbon pressing mechanism has a drawback that, when the piece 11 is slid to replace the ink ribbon 13, the piece 11 is lifted up and does not operate smoothly. The cause is that the force F given by the user to the knob 8 is, as shown in FIG.
Does not pass through the contact bottom surface T, and the piece 11 rotates around the point A.

In order to solve this drawback, the length of the contact piece 11 may be increased by increasing the length of the piece 11, or the operation may be performed even when the user's force F is applied in the downward direction. Such new problems arise. That is, in the former case, the length of the piece 11 in the design in the limited space of the ink ribbon cassette has a drawback that the dead space increases and the ribbon storage space decreases. Further, in the latter, among the components of the force F applied by the user, the horizontal component Fx (FIG. 4) for pressing the spring 12 is reduced, and when the vertical component Fy (FIG. 4) increases, the frictional force with the base 2 also increases. There is a disadvantage that the piece 11 cannot be operated smoothly because it increases in proportion.

FIGS. 5 and 6 show a possible ribbon pressing mechanism for overcoming these disadvantages. In this ribbon pressing mechanism, the piece 11 is covered with a cover member 14, and the knob 8 is taken out of a guide hole 15 formed in the upper surface of the cover 14.

[0006]

By the way, in a ribbon pressing mechanism using such a cover member 14,
The direction of the force F applied by the user to the knob 8 does not pass through the contact bottom surface as shown in FIG. 5, so that the piece 11 rotates around the point A as shown in FIG. Since the cover member 14 only prevents excessive rotation, smooth operation cannot be expected, and the use of the cover member 14 has the disadvantage of increasing the number of parts.

Accordingly, an object of the present invention is to provide an ink ribbon cassette having a simple pressing mechanism for applying tension to the ink ribbon.

[0008]

That is, according to the invention described in claim 1, "(A) the cassette body is formed in a box shape with the bottom piece and the side piece opened at the top, and the side pieces are orthogonal to each other. A gap is formed between the inner wall of one side piece and the tip of the other side piece to provide a slit-shaped ribbon outlet, and the bottom surface of the recess formed on the top face of the tip of the other side piece (B) forming a piece storage hole opening toward the inner wall of one side piece;
(C) Forming a piece consisting of a slide piece having a knob formed on the upper surface and a ribbon pressing piece hanging downward from the tip of the slide piece, the width of the slide piece being slightly larger than the inner width of the piece storage hole. The ribbon pressing piece is placed in the piece storage hole so as to face the inner wall of the side piece on one side, and is stored in a non-contact state with the bottom piece of the cassette body. The lower surface of the slide piece is placed on the bottom surface of the concave portion, and the ribbon pressing piece and the piece are stored. An ink ribbon cassette in which a spring that comes into contact with both of them is inserted between the inner surface of the ink ribbon cassette. "
It is.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the ink ribbon cassette of the present invention will be described with reference to FIGS. FIG. 1 is a cross-sectional view of a main part of the ink ribbon cassette of the invention, and FIG. 2 is a cross-sectional view taken along line AA of FIG. The same parts as those in the conventional example are denoted by the same reference numerals.

In this embodiment, similarly to the above-mentioned conventional example, the cassette main body 1 is formed in a box shape with the bottom piece 2 and the side pieces 3, 4, 5 opened at the top, and the side pieces 3, 4 are mutually connected. A gap is formed between the inner wall of the side piece 3 on one side and the tip of the side piece 4 on the other side, and a slit-shaped ribbon outlet 6 is provided at the orthogonal portion. The piece 11 provided with the knob 8 is urged by the coil spring 12.

The present embodiment is different from the above-described conventional example using the cover member in the following points. That is, a recess 16 is formed on the upper surface of the tip of the side piece 3, a piece storage hole 17 that opens toward the inner wall of the side piece on one side is formed on the bottom of the recess 16, and the knob 8 is formed on the upper surface. , A piece 18a, 18b hanging downward from both sides of the piece 18 and a ribbon pressing piece 19 hanging downward from the tip of the piece 18. The width L of the piece 18 is In order to form the piece 11 in which the inner width of the storage hole 17 is slightly larger and the hanging length of the ribbon pressing piece 19 is slightly shorter than the depth of the piece storage hole 17 so as not to be in contact with the bottom piece 2 of the cassette body 1. , Ribbon pressing piece 1 in piece storage hole 17
9 is placed facing the inner wall of the side piece 3, and the lower surface of the plate piece 18 is placed on the bottom surface of the recess 16, the side piece 18 a of the piece 11,
The engaging claw 11a formed on the side piece 4 is engaged with the guide groove 4a along the sliding direction of the
1 is prevented.

With such a configuration, the ribbon pressing piece 19 of the piece 11 does not contact the bottom piece 2 of the cassette body 1 and the piece 11
Since the sliding portion is the bottom surface of the concave portion 16 on which the plate piece 17 is placed, when the piece 11 is slid for exchanging the ink ribbon, the direction of the force F applied by the user to the knob 8 is close to the knob 8. It passes through the contact bottom surface, that is, the bottom surface of the concave portion 16. For this reason, the piece 11 can slide smoothly without rotating.

[0013]

As described above, according to the present invention, when exchanging the ink ribbon, the piece for pressing the ink ribbon can be slid smoothly without rotating, and the slide of the piece can be reduced in the number of parts. It can be constituted by a mechanism. Therefore, an ink ribbon cassette provided with a simple and reliable tension applying mechanism can be obtained. Further, since the engaging claw formed on the side of the piece is engaged with the guide groove formed on the side piece of the cassette body, the piece does not fall off.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part of an ink ribbon cassette of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a perspective view of a main part of an ink ribbon cassette provided with a conventional ribbon pressing mechanism.

FIG. 4 is a sectional view of the ribbon pressing mechanism of FIG. 3;

FIG. 5 is a sectional view showing another example of the ribbon pressing mechanism of FIG. 3;

FIG. 6 is a cross-sectional view taken along the line BB of FIG. 5 and omitting a coil spring.

FIG. 7 is a sectional view showing an operation state of the ribbon pressing mechanism of FIG. 7;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cassette main body 2 Bottom piece 3, 4, 5 Side piece of cassette main body 4a Guide groove 6 Ribbon outlet 8 Knob 11 Piece 11a Engagement claw 12 Spring 16 Concave part 17 Piece storage hole 18 Plate piece 18a, 18b Side piece 19 Ribbon Pressing piece

Claims (2)

[Claims] (A) A cassette body is formed in a box shape having an upper portion opened at a bottom piece and a side piece, and at a portion where the side pieces are orthogonal to each other, an inner wall of one side piece and a tip end of the other side piece. A slit-shaped ribbon outlet is formed by forming a gap between the side piece and a piece storage hole that opens toward the inner wall of one side piece on the bottom surface of the recess formed on the top of the tip of the other side piece. (B) A piece formed of a slide piece having a knob formed on the upper surface thereof, and a ribbon pressing piece hanging downward from the tip of the slide piece, wherein the width of the slide piece is slightly larger than the inner width of the piece storage hole. (C) storing the ribbon pressing piece in the piece storage hole so as to face the inner wall of one of the side pieces, and store the ribbon pressing piece in a non-contact state with the bottom piece of the cassette body, and put the lower surface of the slide piece on the bottom surface of the concave portion; Do not insert a spring between the ribbon pressing piece and the back of the Ink ribbon cassette. 2. The ink ribbon cassette according to claim 1, wherein an engaging claw formed on a side portion of the piece is engaged with a guide groove formed on a side piece of the cassette body.