GB2244043A

GB2244043A - Ink ribbon cassette

Info

Publication number: GB2244043A
Application number: GB9107986A
Authority: GB
Inventors: Harukazu Shimizu; Akio Tajima; Hiroyuki Harada
Original assignee: Seikosha KK
Current assignee: Seikosha KK
Priority date: 1990-04-17
Filing date: 1991-04-15
Publication date: 1991-11-20
Anticipated expiration: 2011-04-15
Also published as: GB2244043B; DE4112430A1; KR910018200A; GB9107986D0; JPH0462085A; JP2614784B2

Abstract

An ink ribbon cassette, seen in plan view, has horizontal arms 32, 34, Fig. 1, supporting external ribbon span 42 and extending from a flat side of chamber 40 in which zig-zag ribbon folds, extending out of the plane of the drawing, are stored. The ribbon twists between arm 32 and chamber 40, and between chamber 40 and arm 34. A driven cassette roller forms a nip with presser roller 54 to feed ribbon. A guide (70) may aid ribbon twisting (Figs. 4 and 5). The arms 32, 34 may extend at an angle to the plane of the ribbon storage part 31, Fig. 6, and may be pivotal (Fig. 7) to different angles. The ribbon may follow a Möbius path. <IMAGE>

Description

1 "INK RIBBON CASSETTE" : t_i d.!.

This invention relates to an ink ribbon cassette, e.g. for use in printers.

Printers, e.g. for use with computers and word processors, perform printing after an ink ribbon cassette has been inserted in such a way that the ink ribbon of the cassette is aligned with a print head of the printer.

Figure 9 shows a known ink ribbon cassette. In this cassette, a casing has support arms 14 and 16 projecting from opposite ends thereof in the same direction, and an endless ink ribbon 12 is passed around the outside of the casing and is stretched between the support arms 14 and 16. When the cassette is inserted in a printer, a print head 18 is positioned between the support arms 14 and 16 so as to face the ink ribbon 12 which is stretched between the distal ends of the support arms 14 and 16. The casing has a storage chamber 10 within it in which the remainder of the ink ribbon 12 is stored in a zigzag form. During printing, in response to the rotation of rollers 20 and 22, a used part of the ink ribbon 12 between the distal ends of the support arms 14 and 16 is pulled into the storage chamber 10, and at the same time, an unused part of the ink ribbon 12 is sent out of the storage chamber 10 to a position between the distal ends of the support arms 14 and 16.

In the foregoing configuration, however, the size of the cassette is large in the direction in which the support arms 14 and 16 extend (i.e. in the vertical direction in Figure 9), thus limiting the degree of 2 is design freedom of the printer itself. Specifically, the storage distribution of the ink ribbon 12 in the storage chamber 10 becomes dense on the pull-in side and sparse on the send-out side as printing proceeds. Consequently, if the transverse narrow sides of the storage chamber 10 are aligned in the extension direction of the support arms 14 and 16, such an uneven distribution becomes critical. As a result, the resistance acting on the ink ribbon 12 when it is sent out increases and, consequently, the ink ribbon 12 is sent out unevenly, or is sometimes prevented from being sent out at all. Accordingly, the width of the storage chamber 10 in the extension direction of the support arms 14 and 16 must be made large. This prevents one from decreasing the size of the printer in the extension direction of the support arms 14 and 16, or disposing printer components in the extension direction of the support arms 14 and 16 in any given space.

In view of the foregoing circumstances, it is an object of the present invention to provide an ink ribbon cassette whose size in the extension direction of the arm portions such as support arms is small.

According to one aspect of the present invention, there is provided an ink ribbon cassette having a storage chamber in which is stored a first portion of an endless ink ribbon in a convoluted form, the storage chamber having two arm portions at opposite ends respectively thereof which project from the storage chamber and which support a second portion of the ink ribbon which is disposed outside the storage chamber, the opposite edges of the said first portion of the ink ribbon being respectively disposed adjacent to oppositely disposed longitudinally extending main surfaces of the storage chamber, and the said opposite 3 edges lying in a common plane which differs substantially from that of the planes of the said oppositely disposed main surfaces.

Preferably, the said common plane is substantially 1 at right angles to the planes of the said oppositely disposed main surfaces.

Preferably, the distance between oppositely disposed longitudinally extending edges of the storage chamber is at least twice the distance between the said opposite edges of the said first portion of the ink ribbon.

The arm portions may be pivotally connected to the storage chamber, and the ink ribbon may be caused to follow a M6bius curve.

According to another aspect of the present invention, an ink ribbon cassette has a storage chamber for storing an endless ink ribbon in the form of a zigzag line, and two arm portions projecting from opposite ends of the storage chamber for supporting a part of the ink ribbon outside the storage chamber, and is characterised in that the arm portions project at a given angle to the plane of the storage chamber.

Consequently, the transverse narrow sides of the storage chamber are aligned in the extension direction of the arm portions, so that the size of the cassette in the extension direction of the arm portions is decreased.

The invention is illustrated, merely by way of example, in the accompanying drawings, in which:

Figure 1 is a sectional view of a first embodiment of an ink ribbon cassette embodying the present invention; Figure 2 is a sectional view taken along line X-X in Figure 1; Figure 3 is a left side view of the cassette shown 4 in Figure 1; Figure 4 is a sectional view showing a second embodiment; Figure 5 is a sectional view taken along line Y-Y in Figure 4; Figures 6 and 7 are side views of other embodiments; Figure 8 is a sectional view taken along line Z-Z in Figure 7; and Figure 9 is a sectional view of a known ink ribbon cassette.

Figures 1 to 3 show a first embodiment of an ink ribbon cassette 30 embodying the present invention. The ink ribbon cassette 30 may be inserted in a printer (not shown) and used under the control thereof. The ink ribbon cassette 30 is made of a box-shaped casing 31 in which an endless ink ribbon 42 is stored.

As shown in Figure 1, the casing 31 has support arms 32 and 34 projecting from opposite ends thereof in the same direction, and the ink ribbon 42 is passed around the outside of the casing and is stretched between the support arms 32 and 34 so as to define a loop. The support arms 32 and 34 are formed with respective slots 44 and 46 through which the ink ribbon 42 comes into and out of the casing 31. With the cassette inserted in the printer, a print head 47 of the printer is positioned between the support arms 32 and 34, and the print head 47 faces the portion of the ink ribbon 42 which is stretched between the distal ends of the support arms 32 and 34.

As shown in Figure 2, the casing 31 has a storage zhamber 40 defined therein by partition plates 36 and 38 in which a part 42a of the ink ribbon 42 is stored in the form of a zigzag line or in other convoluted form.

0 1 is 1 The partition plates 36 and 38 are formed with respective slits 48 and 50 through which the ink ribbon 42 comes into and passes out of the storage chamber 40.

Provided in the storage chamber 40 are a ribbon roller 52 and a push roller 54 in alignment with the slit 48 of the partition plate 36, and the ink ribbon 42 passes between the two rollers 52 and 54. The push roller 54 is pushed against the ribbon roller 52 by the urging force of a compression coil spring 56 with the ink ribbon 42 interposed between them. With the cassette inserted in the printer, the ribbon roller 52 is coupled to a driving shaft (not shown) of the printer and during the printing operation of the printer, is rotated by means of the driving shaft to advance the ink zibbon 42 in the direction of the arrow A in conjunction with the push roller 54. Due to such an advancing force, a used part 42b of the ink ribbon 42 between the distal ends of the support arms 32 and 34 moves through the slot 44 of the support arm 32 and the slit 48 of the partition plate 36 and is pulled into the storage chamber 40, and at the same time, an unused part 42a of the ink ribbon 42 in the storage chamber 40 moves through the slit 50 of the partition plate 38 and the slot 46 of the support arm 34 and is sent to between the distal ends of the support arms 32 and 34. To apply a predetermined tension to the ink ribbon 42 during its travel, a leaf spring 57 is provided between the support arm 34 on the send-out side of the ink ribbon 42 and the storage chamber 40 to push the ink ribbon 42 against the inner wall surface of the slot 46 of the support arm 34.

As shown in Figure 1, the ink ribbon 42 is stored in the storage chamber 40 such that the widthwise direction of the ink ribbon is in accord with the extension direction of the support arms 32 and 34.

1 6 Specifically, the support arms 32 and 34 project at right angles (i.e. in the direction of the arrow B) to the plane of the storage chamber 40, Thus the opposite edges-42c, 42d of the part 42a of the ink ribbon 42 are respectively disposed adjacent to oppositely disposed longitudinally extending main surfaces 40a, 40b of the storage chamber 40, and the opposite edges 42c, 42d (i.e. in a common plane which differs substantially, e.g. by 900 as shown, from that of the planes of the oppositely disposed main surfaces 40a, 40b). Moreover, the distance between the oppositely disposed longitudinally extending edges 40c, 40d of the storage chamber 40 is at least twice, and may be four times or more, the distance between the opposite edges 42c, 42d of the part 42a of the ink ribbon 42.

Specifically, as shown in Figure 2, the slit 48 of the partition plate 36 is formed such that its widthwise direction is in accord with the lengthwise direction of the slot 44 of the support arm 32. Therefore, the ink ribbon 42 is twisted through an angle of 90 degrees between the support arm 32 and the partition plate 36. Similarly, the slit 50 of the partition plate 38 is formed such that its widthwise direction is in accord with the lengthwise direction of the slot 46 of the support arm 34. Therefore, the ink ribbon 42 is twisted through an angle of 90 degrees between the partition plate 38 and the support arm 34. Accordingly, the support arms 32 and 34 project at right angles to the main plane of the storage chamber 40, and the ink ribbon 42 is stored in the storage chamber 40 such that the widthwise direction of the ink ribbon is in accord with the extension direction of the support arms 32 and 34.

In the case of the ink ribbon cassette 30 of 7 A Figures 1 and 2, the support arms 32 and 34 project at right angles to the main plane of the storage chamber 40, and the transverse narrow sides of the storage chamber 40 are aligned in the extension direction of the support arms 32 and 34. As a result, the size of the cassette in the extension direction of the support arms 32 and 34 is decreased. Consequently, a section of the printer in which the ink ribbon cassette 30 is inserted and received can be decreased in size in the extension direction of the support arms 32, 34, the size of the printer in that direction can be decreased, and thus, the degree of freedom in determining the mounting position of each component of the printer can be enhanced.

Further, since the support arms 32 and 34 project at right angles to the main plane of the storage chamber 40, the size of the cassette in the direction (the lateral direction in Figure 3) along the main plane of the storage chamber 40 is decreased (see Figure 3). Consequently, where the cassette is inserted in the printer such that the storage chamber 40 takes a horizontal position, the size of the cassette receiving section of the printer in the horizontal direction can be decreased substantially, thus allowing a decrease in the horizontal size of the printer. On the contrary, where the cassette is inserted in the printer such that the storage chamber 40 takes a vertical position, the size of the cassette receiving section of the printer in the vertical direction can be decreased substantially, thus allowing a decrease in the thickness of the printer.

Further, since the support arms 32 and 34 project at right angles to the main plane of the storage chamber 40, the degree of design freedom of the ink ribbon 1 is 1 8 cassette 30 itself is enhanced.

To control the movement of the ink ribbon 42, as shown in Figures 4 and 5, an auxiliary guide 70 may be provided between the support arm 32 on the pull-in side of the ink ribbon 42 and the partition plate 36, the auxiliary guide 70 being in contact with the ink ribbon 42. In this case, the twisted state of the ink ribbon 42 can be reliably maintained during the printing operation, thereby preventing the ink ribbon 42 from being twisted excessively during the printing operation. It should be noted that between the support arm 34 on the send-out side and the partition plate 38, no large tension acts on the ink ribbon 42 during the printing operation. Therefore, even where such an auxiliary guide is not provided for controlling the movement of the ink ribbon 42, the ink ribbon 42 is never twisted excessively during the printing operation.

Further, an anti-friction roller (not shown) may be provided in a zone where the ink ribbon 42 changes its direction, especially in a zone on the pull-in side where a large tension acts during the printing operation, or in a C zone as shown in Figure 1. In this case, the resistance acting on the ink ribbon 42 when it is pulled in is reduced, whereby the ink ribbon 42 can be smoothly pulled in.

As the ink ribbon 42, an ordinary ring ribbon or a Mbbius ribbon i.e. a ribbon which is caused to follow a M6bius curve, can be used. Epsecially, where a M6bius ribbon is used, the ink ribbon 42 can be twisted a total angle of 180 degrees naturally in two zones; one half angle of 90 degrees in the zone between the partition plate 36 and the support arm 32 and the other half angle of 90 degrees in the zone between the partition plate 38 and the support arm 34. Therefore, the resistance 1 9 acting on the ink ribbon 42 when it advances is reduced, whereby the ink ribbon 42 can be smoothly advanced.

Although the foregoing embodiments include the partition plates 36 and 38 formed with the slits 48 and 50, other means may be used to twist the ink ribbon 42 between the partition plate 36 and the support arm 32 and between the partition plate 38 and the support arm 34, this being realized, for example, by providing a guide for causing the ink ribbon 42 to twist an angle of 90 degrees.

Although the foregoing embodiments include the support arms 32 and 34 projecting at right angles to the main plane of the storage chamber 40, it is possible to arrange, as shown in Figure 6, that the support arms 32 and 34 are such as to project obliquely to the main plane of the storage chamber 40. In this case, also, the transverse narrow sides of the storage chamber 40 are aligned in the extbnsion direction of the support arms 32 and 34. Therefore, the size of the cassette in the extension direction of the support arms 32 and 34 is decreased. Further, by arranging the support arms 32 and 34 obliquely to the plane of the storage chamber 40, the disposition of the print head 47 in relation to the storage chamber 40 can be changed as desired so that the degree of design freedom is enhanced. It is desirable that the projection angle 0 of the support arms 32 and 34 to the plane of the storage chamber 40 be within the range of 45 degrees to 90 degrees.

Although the foregoing embodiment includes the support arms 32 and 34 being fixed, it is also possible, as shown in Figures 7 and 8, to arrange that the support arms 32 and 34 are rotatably pivoted via pins 72 to the side walls of the casing 31 and are adapted to be kept stationary at a desired rotational i is position by the use of fixing means (not shown). In Figures 7 and 8, reference numeral 74 designates holes through which the ink ribbon 42 passes. In this case, since the projection angle of the support arms 32 and 34 to the main plane of the storage chamber 40 can be set to a desired value by adjusting the rotational position of the support arms 32 and 34, this embodiment can be used compatibly in several different types of printers which differ from one another in terms of the disposition of the print head 47 with respect to the storage chamber 40. Where a click mechanism or the like is provided between the support arms 32 and 34 and the side wall of the casing 31 to lock the support arms 32 and 34 to the side wall of the casing 31 at any one of several rotational positions, the rotational position of the support arms 32 and 34 can be readily adjusted.

In the embodiments described above, the arm portions are made to project at a given angle to the main plane of the storage chamber. Therefore, the transverse narrow sides of the storage chamber are aligned in the extension direction of the arm portions, so that the size of the storage chamber in the extension direction of the arm portions is decreased. Further, the size of the cassette in the direction along the main plane of the storage chamber is decreased. Therefore, the horizontal size of the printer in which the storage chamber is positioned horizontally can be decreased, or the thickness of the printer in which the storage chamber is positioned vertically can be decreased.

ik J 1 j 1.

11

Claims

1. An ink ribbon cassette having a storage chamber in which is stored a first portion of an endless ink ribbon in a convoluted form, the storage chamber having two arm portions at opposite ends respectively thereof which project from the storage chamber and which support a second portion of the ink ribbon which is disposed outside the storage chamber, the opposite edges of the said first portion of the ink ribbon being respectively disposed adjacent to oppositely disposed longitudinally extending main surfaces of the storage chamber, and the said opposite edges lying in a common plane which differs substantially from that of the planes of the said oppositely disposed main surfaces.

2. An ink ribbon cassette as claimed in claim 1 in which the said common plane is substantially at right angles to the planes of the said oppositely disposed main surfaces.

3. An ink ribbon cassette as claimed in claim 1 or 2 in which the distance between oppositely disposed longitudinally extending edges of the storage chamber is at least twice the distance between the said opposite edges of the said first portion of the ink ribbon.

4. An ink ribbon cassette as claimed in any preceding claim in which the arm portions are pivotally connected to the storage chamber.

5. An ink ribbon cassette as claimed in any preceding claim in which the ink ribbon is caused to follow a M6bius curve.

i 1 f k_ 12

6. An ink ribbon cassette substantially as hereinbefore described with reference to and as shown in the accompanying drawings.

7. An ink ribbon cassette having a storage chamber for storing an endless ink ribbon in the form of a zigzag line, and two arm portions projecting from both ends of the storage chamber for supporting a part of the ink ribbon outside the storage chamber, characterised in that the arm portions project at a given angle to the plane of the storage chamber.

8. An ink ribbon cassette according to claim 7, wherein the arm portions project at right angles to the plane of the storage chamber.

9. An ink ribbon cassette according to claim 7, wherein the arm portions are swingably pivoted to both ends of the storage chamber.

10. An ink ribbon cassette according to any of claims 7-9 wherein the ink ribbon is a Mbbius ribbon.

11. Any novel integer or step, or combination of integers or steps, hereinbefore described and/or as shown in the accompanying drawings, irrespectcive of whether the present claim is within the scope of, or relates to the same or a different invention from that of, the preceding claims.

Published 1991 at The Patent Office. Concept House. Cardiff Road, Newport. Gwent NP9 IRH. Further copies may be obtained from Sales Branch, Unit 6. Nine Mile Point, CwnifelWach. Cross Keys, Newport, NP1 7HZ. Printed by Multiplex techniques ltd, St Mary Cray. Kent.

1 1