JPH08156374A - Ink ribbon cassette of printer - Google Patents

Abstract

PURPOSE: To mount only a fitted indicated ink ribbon unit by forming a constricted part or stopper piece permitting only a fitted shaft diameter to pass to the elastic member of the ink ribbon cassette corresponding to the spool shaft of an ink ribbon unit. CONSTITUTION: When an ink ribbon unit is mounted on an ink ribbon cassette, if the respective shaft parts of a pair of the spool shafts of the unit have a predetermined diameter or more, a stopper piece 35 is opened when the respective shaft parts pass through the constricted parts 34 of the elastic member 30 of the cassette to come into contact with an outside prescribing wall and, therefore, the passage of the shaft parts is prevented. When the fine diameter parts 25a of the respective shaft parts have a predetermined diameter, the fine diameter parts 25a pass through the constricted parts 34 of the elastic member 30. Therefore, the unit having both spool shafts can be mounted on the cassette. At this time, the grasping pieces 31 of the elastic ember 30 energize the spool shafts to prevent the backlash thereof. A positioning means 12 prevents the movement of the elastic member 30.

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 used in a printer for printing a recorded image such as a video image as a hard copy, a so-called color photograph.

[0002]

2. Description of the Related Art Conventionally, as an ink ribbon cassette used in this type of printer, for example, there is one as shown in FIG. This ink ribbon cassette is composed of a cassette body 1 composed of a pair of upper and lower detachable upper shells 2 and lower shells 3, and a pair of leaf springs housed in the cassette body 1.

The lower shell 3 has a substantially boat shape, one end side of which is provided with drive side bearing portions 4 and 4 having circular bearing holes 4a, 4a, and the other end side of which is U-shaped. A driven side bearing portion 5 having a bearing is provided. The upper shell 2 is detachably incorporated into a portion of the lower shell 3 having the driven side bearing portion 5, and the driven side bearing portion 5 of the lower shell 3 is attached to the upper shell 2.
A pair of leaf springs is attached at a position corresponding to.

As shown in FIG. 10, the ink ribbon unit 6 housed in the ink ribbon cassette having such a structure has a ribbon supply spool shaft 8 around which an unused ink ribbon 7 is wound, and used ink. A ribbon winding spool shaft 9 for winding the ribbon 7 is configured.
Ribbon supply spool shaft 8 and ribbon winding spool shaft 9
Drive-side shaft portions 10 and 11 are provided at one end portions of the drive-side shaft portions 10 and 11, respectively, and drive-side shaft portions 10 and 11 have drive shaft holes 10a and 1
1a and drive claws 10b and 11b on the inner peripheral surface thereof are formed. Further, driven side shafts are provided at the other ends of the ribbon supply spool shaft 8 and the ribbon take-up spool shaft 9, respectively, and U-shaped bearings are formed at the driven side shafts.

[0005]

However, in the ink ribbon cassette of the conventional printer as described above, the ink ribbon unit 6 is mounted on the ink ribbon cassette by the ribbon supply spool shaft 8 and the ribbon take-up of the ink ribbon unit 6. The drive side shaft portions 10 and 11 of the spool shaft 9 are connected to the drive side bearing portions 4 of the ink ribbon cassette 4.
After being fitted in the bearing holes 4a, 4a of No. 4, the driven side shaft portions of the ribbon supply spool shaft 8 and the ribbon take-up spool shaft 9 are fitted in the bearings of the driven side bearing portion 5. Therefore, the shaft diameter of the drive side shaft portions 10 and 11 and the bearing hole 4
If the hole diameters of a and 4a are the same and the shaft diameter of the driven side shaft portion and the diameter of the bearing are the same, it is an ink ribbon unit other than the designated ink ribbon unit of different type, manufacturer, and various other types. However, there is a problem in that the ink ribbon unit other than the designated one may be mistakenly used.

The present invention has been made in view of such conventional problems, and an object of the present invention is to provide an ink ribbon cassette of a printer which can use only a designated ink ribbon unit suitable for the ink ribbon cassette. I am trying.

[0007]

In order to solve the above-mentioned problems and the like and to achieve the above-mentioned objects, the present invention, for example, as shown in FIGS.
An ink ribbon unit 27 having a ribbon supply spool shaft 18 around which is wound and a ribbon take-up spool shaft 19 for winding a used ink ribbon 7, and a cassette body 1 to which the ink ribbon unit 27 is detachably attached, and attached to the cassette body 1. Ribbon supply spool shaft 18 and ribbon take-up spool shaft 19
In the ink ribbon cassette of the printer, in which the elastic members 30 and 40 for engaging and holding one of the shaft portions 20 and 21 provided at both ends of the spool ribbons 18 and 19 are replaceable, Shaft 2
0 and 21 are formed with small-diameter portions 25a and 25a having a small shaft diameter, and the elastic members 30 and 40 are provided with a small-diameter portion at a distance b ₂ substantially equal to the shaft diameter d ₁ of the small-diameter portion 25a. The pair of sandwiching pieces 31, 31 provided in parallel so as to sandwich 25a, and the interval b ₂ between the pair of sandwiching pieces 31, 31 provided on the upper part of at least one sandwiching piece 31 of the sandwiching pieces 31, 31 is reduced. Constricted portions 34, 34 that are narrower than the shaft diameter d ₁ of the diameter portion 25a,
On the constricted portions 34, 34, stopper pieces 35, 35 extending outward so as to be continuously wide are provided.
The restriction wall 2 for restricting the opening of the stopper pieces 35, 35
8 and 28 are provided, and the small diameter portion 25a is constricted by the narrowed portions 34 and 3 in the gap between the end portions of the stopper pieces 35 and 35 and the restriction walls 28 and 28.
It is characterized in that it is set so that the end portions of the stopper pieces 35, 35 come into contact with the restriction walls 28, 28 when passing through 4.

Further, in the ink ribbon cassette of the printer of the present invention, for example, as shown in FIGS. 7 and 8, the pair of sandwiching pieces 31, 31 of the elastic member 30 includes the spool shaft 18,
The spool shaft 1 is engaged with the small-diameter portions 25a of the 19 and 25a.
8 and 19 may be configured to be urged in the axial direction.

Further, in the ink ribbon cassette of the printer of the present invention, for example, as shown in FIGS. 1 to 3, the cassette body 1 is provided with positioning means 12, 12 for positioning the elastic member 30. Good.

[0010]

The present invention has the above-mentioned configuration,
When the ink ribbon unit 27 is attached to the ink ribbon cassette, when the shaft diameters at the predetermined positions of the shaft portions 20 and 21 of the pair of spool shafts 18 and 19 of the ink ribbon unit 27 are larger than a predetermined size, respectively. Predetermined positions of the shaft portions 20, 21 are constricted portions 34, 3 of the elastic member 30.
4, the stopper pieces 35, 35 are opened and come into contact with the regulating walls 28, 28 of the cassette body 1 located on the outer side, and the passage of the shaft portions 20, 21 is blocked, so that the spool shaft 18, The insertion of the ink ribbon 19 becomes impossible, and the ink ribbon unit having the spool shafts 18 and 19 is prevented from being attached to the ink ribbon cassette.

On the other hand, the pair of spool shafts 18, 1
Narrow-diameter portion 25 provided on each one of the shaft portions 20 and 21
When the shaft diameters of a and 25a are a predetermined size, the ends of the stopper pieces 35 and 35 that are opened when the small diameter portion 25a passes through the constricted portions 34 and 34 of the elastic member 30 have a regulation wall. 28, so that the small diameter portion 2
5a allows the constricted portions 34, 34 to pass therethrough, and allows the shaft portions 20, 21 to pass therethrough, so that the spool shafts 18, 19 can be inserted, and the ink ribbon unit 27 having the spool shafts 18, 19 is inserted. Is mounted on the ink ribbon cassette.

Further, a pair of sandwiching pieces 31 of the elastic member 30,
By urging the spool shafts 18 and 19 in the axial direction by 31, it is possible to prevent the spool shafts 18 and 19 from moving in the axial direction and prevent rattling.

Further, by mounting the elastic member 30 on the cassette body 1 by using the positioning means 12, 12, it is possible to prevent the elastic member 30 from moving and securely mount the elastic member 30 at a predetermined position.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 8 show an embodiment of the present invention, FIG. 1 is an exploded perspective view showing a state before mounting an ink ribbon unit, FIG. 2 is an enlarged perspective view of an elastic member shown in FIG.
3 is a front view of the elastic member shown in FIG. 2, FIG. 4 is an explanatory view showing the relationship between the stopper piece of the elastic member and the regulation wall of the cassette body, and FIG. 5 is a plan view showing the driven side shaft portion of the spool shaft. Figure 6
8 shows an assembled state of the elastic member attached to the cassette main body and the driven side shaft portion of the spool shaft. FIG. 7 is a plan view of a part of the state before the printer is set, FIG. 7 is a front view of FIG. 6, and FIG. FIG. 3 is a front view in which a part of the state after setting the printer is cross-sectional. FIG. 9 is a front view showing another embodiment of the elastic member according to the present invention. Note that, in FIG. 1 and the like, the same portions as those in FIG.

As shown in FIG. 1, on both sides of the bearings 5a, 5a of the driven side bearings 5, 5 of the lower shell 3, there are slits 12, showing a specific example of positioning means for positioning the elastic member. 12 are provided respectively. The driven-side bearing portions 5 and 5 having the bearings 5a and 5a and the slits 12 and 12 are provided inside the rear plate 14 with a predetermined space therebetween, and are separated from each other by a plurality of ribs 15 and 15 extending in the front-rear direction. It is connected and reinforced. Furthermore, the lower shell 3
An opening window 16 is provided at the center of the lower surface of the printer so that a print head (not shown) faces the printer when the printer is attached to the printer.

Further, the upper shell 2 has substantially semicircular upper shell bearings 17, 17 which cover the upper surface side of the driven side bearings 5, 5 of the lower shell 3, and the upper shell bearings 17, 17 are provided in the respective upper shell bearings 17, 17. Is a U-shaped bearing 17a, 1 that opens from the upper surface to the front surface
7a is provided. Inside the bearings 17a, 17a, an opening 1 for exposing a spring or the like described later is provided.
7b and 17b are provided. Further, each bearing 17a, 17
At the upper part of a, the driven side shaft portion 20 of the ribbon supply spool shaft 18 and the driven side shaft portion 2 of the ribbon take-up spool shaft 19 rotatably supported by these bearings 17a, 17a.
A guide surface 17c for facilitating the inserting operation of 1.
17c is provided. Then, bearing pieces 22, 22 for supporting the upper surfaces of the driven side shaft portion 20 and the driven side shaft portion 21 are provided on the back surfaces of the bearings 17a, 17a, respectively.

The ribbon supply spool shaft 18 and the ribbon take-up spool shaft 19 are driven shaft portions 20 and 21 provided at one end portion in the axial direction and the drive side shaft portion 1 provided at the other end portion.
0, 11 and flanges 23,
23 and 24, 24 are provided. Driven shaft 2
0 and 21 are, as shown in FIGS.
A large diameter portion 25 projecting axially outward from 24 and a small diameter portion 26 projecting axially outward from the tip of the large diameter portion 25 are provided with an annular groove continuous in the circumferential direction. To form a small diameter portion 25a. The shaft diameter of the small diameter portion 25a is d _1, and the shaft diameter of the large diameter portion 25 is d ₂ (d ₁ <
d ₂ ).

The other structure is the same as that of the conventional example, and the ink supply ribbon shaft 27, the ribbon take-up spool shaft 19, and the ink ribbon 7 having the above-described structure form an ink ribbon unit 27. .

Reference numeral 30 shown in FIG. 1 is a spring which is a specific example of an elastic member which engages and holds the driven side shaft portions 20 and 21 of the ribbon supply spool shaft 18 and the ribbon winding spool shaft 19, respectively. This spring 30, as shown in the enlarged view of FIG. 2 and FIG.
1. A pair of holding pieces 31, 31 provided in parallel so as to hold 1 from the left and right, and a pair of fixing portions 32, 32 for fixing the holding pieces 31, 31 to the cassette body side. Is bent into a predetermined shape.

The fixing portion 32 of the spring 30 is the lower shell 3
The driven-side bearing portion 5 is formed in a U shape so that it can be sandwiched from the front and rear, and the left and right fixing portions 32 and 32 are connected by a connecting piece 33 that extends laterally along the bottom surface of the lower shell 3. ing. The pair of holding pieces 31, 31 are formed so as to be parallel to each other with an interval substantially equal to the shaft diameter of the small diameter portion 25a of the driven side shaft portions 20, 21.
Constricted portions 34 and 34 are formed on the upper portions of the reference numerals 1 and 31 so as to be narrower than the shaft diameter of the small diameter portion 25a and formed into a dogleg shape. The stopper pieces 35, 35 are formed so as to extend obliquely upward so that

The two springs 30 having such a structure are attached to the driven side bearing portions 5 and 5 so as to surround the bearings 5a and 5a, respectively, and the upper end pieces of the pair of fixing portions 32 and 32, respectively. Is positioned by engaging the slits 12, 12 provided on both sides of the bearing 5a. Then, the constricted portion 3 of the pair of sandwiching pieces 31, 31.
In order to regulate the size of the shaft diameter of the shaft portion that can pass through the holes 4, 34, as shown in FIGS. 4 and 6, the upper shell 2 can be in contact with the tips of the stopper pieces 35, 35. Walls 28, 28 are provided. Therefore, the restriction walls 28, 28 are set at the back of the openings 17b, 17b of the upper shell bearings 17, 17, and the upper portions of the sandwiching pieces 31, 31 are inserted into the bearings 17a, 17a from the openings 17b, 17b. It is protruding. Reference numeral 29 shown in FIGS. 7 and 8 is a pressing piece, and the pressing piece 29 presses the spring 30 from above and prevents the spring 30 from rising.

When the space between the restriction walls 28 and 28 is L, the space L, the dimensions of the spring 30, and the small diameter portion 2 are set.
The length relationship of the shaft diameter 5a with the shaft diameter d ₁ is as follows. Here, the interval between the constricted portions 34, 34 of the spring 30 is b ₁ , the interval between the sandwiching pieces 31, 31 is b ₂ , the interval between the tips of the stopper pieces 35, 35 in the free state is b ₃ , and the constricted portion 34 is the stopper piece 35 spacing between the tips when between 34 small-diameter portion 25a (the shaft portion of the predetermined dimension) pass b ₄
And

That is, b ₃ + (d ₁ −b ₁ ) = b ₄ . Then, the gap b ₄ at this time is set to the restriction walls 28, 28.
It is set equal to the interval L (b ₄ = L) or slightly smaller. As a result, when the small-diameter portion 25a of the driven-side shaft portions 20, 21 passes through the constricted portions 34, 34 of the spring 30, the stopper pieces 35, 35 are opened to the extent that the open-side end portions thereof respectively contact the restriction walls 28, 28. Is opened.

The ink ribbon cassette having such a structure can be easily assembled as follows, for example. First, the springs 30 are attached to the driven-side bearing portions 5 and 5 of the lower shell 3, respectively. In this case, the spring 30 has the fixing portion 32, with the holding piece 31 facing forward.
32 is fitted into the driven side bearing portions 5 and 5, and each fixed portion 32,
The upper ends of 32 are engaged with the slits 12, 12, respectively.
Accordingly, the spring 30 is attached to the driven-side bearing portion 5 in a state of being positioned with respect to the bearing 5a, and the central portion between the pair of sandwiching pieces 31, 31 comes to coincide with the central portion of the bearing 5a.

Next, the upper shell 2 is aligned with the driven side of the lower shell 3 so as to cover the driven side bearing portions 5, 5, and the upper shell 2 is pressed toward the lower shell 3 side so that both shells 2, 3 are connected. To coalesce. This completes the work of assembling the ink ribbon cassette. The attachment / detachment work of the ink ribbon unit 27 to / from the ink ribbon cassette can be easily performed as follows, for example.

First, the drive side shaft portion 10 of the ribbon supply spool shaft 18 is fitted into the bearing hole 4a of the drive side bearing portion 4 of the lower shell 3 from the inside, and then the driven side shaft portion 20 of the upper shell 2 is fitted. The upper shell bearing portion 17 is inserted into the bearing 17a from above.
Next, similarly, the drive side shaft portion 11 of the ribbon take-up spool shaft 19 is connected to the bearing hole 4a of the drive side bearing portion 4 of the lower shell 3.
Then, the driven side shaft portion 21 is inserted into the bearing 17a of the upper shell bearing portion 17 of the upper shell 2 from above.

In this case, when the ink ribbon unit 27 is a product made for the ink ribbon cassette according to this embodiment, in other words, a designated component of the ink ribbon cassette, it is simply and surely mounted as follows. be able to. That is, when the ink ribbon unit 27 is a designated component of the ink ribbon cassette, the driven side shaft portions 20 and 21 of the ribbon supply spool shaft 18 and the ribbon take-up spool shaft 19 are both formed with small diameter portions 25a and 25a. Therefore, when the driven side shaft portion 20 (or 21) of the bearing 17a of the upper shell bearing portion 17 is inserted from above, first, the small-diameter portion 25a causes the pair of holding pieces 3 of the spring 30 to move.
It contacts the constricted portions 34, 34 of 1, 31.

From this state, when the driven side shaft portion 20 (or 21) is pressed against the spring force of the pair of sandwiching pieces 31, 31, the constricted portions 34, 34 are elasticized by the sandwiching pieces 31, 31.
Elastically deform rearward to allow the small diameter portion 25a to pass therethrough. Then, the small-diameter portion 25a has the constricted portion 34,
When passing through the narrowest part of 34, stopper pieces 35, 35 continuous to the upper part of each constricted part 34, 34
The tip of the contact with the restriction walls 28, 28 of the upper shell 2,
Or move to the vicinity. Therefore, in this case, since the small diameter portion 25a passes through the constricted portions 34, 34, the large diameter portion 2
5 can be inserted and supported in the bearing 5a and the bearing 17a.

As a result, in the state shown in FIGS. 6 and 7, the driven-side shaft portion 20 (or 21) is moved to both bearings 5a and 17a.
Rotatably supported by. At this time, the gap b ₂ between the pair of holding pieces 31, 31 is set to be slightly larger than the shaft diameter d ₁ of the small diameter portion 25a, so that the small diameter portion 25a
It is possible to prevent the outer peripheral surface of the from contacting the inner surfaces of the sandwiching pieces 31, 31. Therefore, the small-diameter portion 25a and the sandwiching pieces 31, 3
It is possible to prevent the frictional force from being generated between the ribbon supply spool 1 and the roller 1, and to ensure that the ribbon supply spool shaft 18 and the ribbon take-up spool shaft 19 rotate smoothly. In addition, FIG.
In the state of FIG. 7, since the upper portions of the bearings 5a and 17a are open, the driven side shaft portions 20 and 21 try to move upward due to an external force such as vibration.
Since the movement is restricted by the constricted portions 34, 34 by 1, the driven-side shaft portions 20, 21 do not accidentally come off from the bearings 5a, 17a.

On the other hand, when the ink ribbon unit 27 is taken out from the ink ribbon cassette, the sandwiching pieces 31, 3 are used.
The driven shaft portions 20 and 21 are pulled upward against the spring force of 1. As a result, the constricted portions 34, 34 retreat and the distance b ₁ between them is expanded to the diameter of the small diameter portion 25a, so that the driven side shaft portions 20, 21 can be pulled out from the bearings 5a, 17a.

On the other hand, when the ink ribbon unit is not a designated part of the ink ribbon cassette according to the present embodiment, for example, a shaft having the same shaft diameter as the conventional driven shaft but having no small diameter portion 25a. Part (for example, when the shaft diameter is d ₂ ), the driven side shaft part cannot be inserted into the bearing, and therefore such an ink ribbon unit cannot be used in this ink ribbon cassette. .

That is, when the conventional driven side shaft portion having no small diameter portion 25a is inserted into the bearings 5a and 17a, the driven side shaft portion smoothly enters until it reaches the constricted portions 34 and 34, but the driven side portion When the constricted portions 34, 34 are opened by the shaft portion, the tips of the stopper pieces 35, 35 come into contact with the restriction walls 28, 28 before the driven-side shaft portion passes through the constricted portions 34, 34. Therefore, the driven-side shaft portion cannot pass through the constricted portions 34, 34, and eventually the ink ribbon cassette cannot be used. Therefore, according to the present embodiment, only the dedicated ink ribbon unit as described above can be used in the ink ribbon cassette according to the present embodiment, and an ink ribbon unit which is not a designated part other than the standard is misused. Can be prevented.

In the ink ribbon cassette in which the designated ink ribbon unit 27 is mounted in this way, the driven side shaft portions 20, 21 before being mounted in the printer are held in the state shown in FIG. That is, the two large diameter portions 25, 25 set on both sides of the small diameter portion 25a are connected to the lower shell 3
Is supported from below by the bearing 5a of the upper shell 2 and the bearing 17a of the upper shell 2, but their upper portions are in a free state,
The constricted portions 34, 34 of the spring 30 are located above it. The small-diameter portion 26 of the driven-side shaft portions 20 and 21 is completely free.

When this ink ribbon cassette is set in the printer from this state, the drive shaft of the printer (not shown) is fitted to the drive side shaft portions 10 and 11 of the ribbon supply spool shaft 18 and the ribbon take-up spool shaft 19, respectively. 8, as shown in FIG.
It slides toward the driven bearings 5, 5 against the biasing force of 30. As a result, the large diameter portion 25 of the driven side shaft portions 20 and 21 slides on the bearings 5a and 17a, while the small diameter portion 26 enters the lower side of the bearing piece 22 of the upper shell 2 and the bearing piece 22
The upper end of the small diameter portion 26 contacts the lower surface of the. As a result, the driven side shaft portions 20 and 21 have the bearing 5a of the lower shell 3 and the upper shell 2
The bearing 17a and the bearing piece 22 are rotatably held from above and below, and the looseness of the driven side shaft portions 20 and 21 is removed, so that smooth rotation is possible.

Further, the spring 40 shown in FIG.
Of the pair of holding pieces 31, 31 of the spring 30 shown in FIG. 3, the constricted portion 34 of the right side holding piece 31 is eliminated and the constricted portion 34 is provided only on the left side holding piece 31. As described above, the same effect as that of the above-described embodiment can be obtained by providing the constricted portion 34 on only one of the pair of sandwiching pieces 31, 31.

In this case, the holding piece 4 without the constricted portion 34
It is necessary to set the height of 1 to be appropriately longer than the height of the constricted portion 34 of the other sandwiching piece 31 by the length e. By making the height of the sandwiching piece 41 higher than the height of the constricted portion 34 in this way, it is possible to apply the rotational force X toward the constricted portion 34 side to the small diameter portion 25a passing through the constricted portion 34. As a result, the sandwiching piece 31 having the constricted portion 34 can be surely bent and deformed. Even with the sandwiching piece 41 without the constricted portion 34, the stopper piece 42 for guiding the small diameter portion 25a may be provided as shown by the chain double-dashed line in FIG.

As described above, the present invention is not limited to the above-mentioned embodiment. For example, in the above-mentioned embodiment, the springs 30 and 40 using the steel wire as the elastic member have been explained. It is also possible to use a spring formed in a substantially similar shape by using. Further, the shape of the constricted portion 34 is not limited to the above-described embodiment having the dogleg shape, but may be another shape such as an arc shape. Further, it is also possible to provide a pair of sandwiching pieces as separate bodies and individually fix the sandwiching pieces to the lower shell or the like by the respective fixing portions provided.

Further, in the above embodiment, an example in which the regulating wall 28 is provided on the upper shell 2 has been described, but the regulating wall can be provided on the lower shell. Further, in the above embodiment, the driven side shaft portions 20 and 21 are provided with the small diameter portions 25a to be engaged and held by the springs 30 and 40. However, conversely, the drive side shaft portions 10 and 11 are provided. Alternatively, a small diameter portion 25a may be provided to engage and hold with an elastic member. Furthermore, although the example in which the slits 12, 12 are provided as the positioning means has been described, for example, a structure in which an engaging protrusion is provided on the bearing portion to position the elastic member may be used. As described above, the present invention can be variously modified without departing from the spirit thereof.

[0039]

As described above, according to the present invention,
A small diameter portion is formed on one shaft portion of the spool shaft, a sandwiching piece having a constriction portion and a stopper piece and a fixing portion are formed on the elastic member, and a regulation wall is provided on the cassette body, and the stopper piece and the regulation wall. Since the gap between and is set so as to touch the regulation wall when the small-diameter portion passes, only the specified ink ribbon unit that is compatible with this ink ribbon cassette can be installed, and therefore the dedicated ink ribbon unit It is possible to use only the ink ribbon unit other than the designated one, and it is possible to prevent the ink ribbon unit from being misused.

Further, by arranging the pair of elastic members to urge the spool shaft in the axial direction, the urging force urges the spool shaft in the axial direction, so that the spool shaft rattles in the axial direction. The effect of being able to prevent sticking is obtained.

Further, by arranging the elastic member on the cassette body by using the positioning means, it is possible to prevent the elastic member from moving due to vibration and the like, and it is possible to always attach the elastic member at a predetermined position. can get.

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention and is an exploded perspective view of a state before mounting an ink ribbon unit.

FIG. 2 is a perspective view showing an embodiment of an elastic member according to the present invention.

FIG. 3 is a front view of the elastic member shown in FIG.

FIG. 4 is an explanatory diagram showing the relationship between the stopper piece of the elastic member shown in FIG. 2 and the regulation wall of the cassette body.

FIG. 5 is an explanatory view showing a driven side shaft portion of the spool shaft according to the present invention.

6 shows an assembled state of the driven shaft portion of the spool shaft shown in FIG. 5 and an elastic member attached to the cassette body, and is a plan view in which a part of the state before being set in the printer is shown in section.

7 is a cross-sectional view of the front side of FIG.

FIG. 8 is a front view in which a part of the state after setting the printer in the state of FIG. 7 is shown in section.

FIG. 9 is a front view showing another embodiment of the elastic member according to the present invention.

FIG. 10 is a perspective view showing a state in which an ink ribbon unit is attached to a conventional ink ribbon cassette.

[Explanation of symbols]

 1 Cassette Main Body 2 Upper Shell 3 Lower Shell 7 Ink Ribbon 10, 11 Drive Side Shaft 12 Slit (Positioning Means) 17 Upper Shell Bearing 17a Bearing 17b Opening 18 Ribbon Supply Spool Shaft 19 Ribbon Winding Spool Shaft 20, 21 Driven Side shaft portion 22 Bearing piece 25 Large diameter portion 25a Small diameter portion 26 Small diameter portion 27 Ink ribbon unit 28 Control wall 30,40 Spring (elastic member) 31 Holding piece 32 Fixing portion 34 Constriction portion 35 Stopper piece

Claims (3)

[Claims] 1. A cassette body to which an ink ribbon unit having a ribbon supply spool shaft around which an unused ink ribbon is wound and a ribbon take-up spool shaft around which a used ink ribbon is wound is detachably mounted, A printer that includes an elastic member that engages and holds one of shaft portions provided at both ends of the ribbon supply spool shaft and the ribbon take-up spool shaft mounted on the cassette body, and in which the ink ribbon unit is replaceable In the ink ribbon cassette described in (1), a small diameter portion having a small shaft diameter is formed on one of the shaft portions of the spool shaft, and the elastic member is provided with the thin diameter portion at a distance substantially equal to the shaft diameter of the thin diameter portion. A pair of sandwiching pieces that are provided in parallel so as to sandwich the diameter portion, and a gap between the pair of sandwiching pieces that is provided on the upper part of at least one of the sandwiching pieces and that has the above-mentioned narrowing interval. A constricted portion that is narrower than the shaft diameter of the diameter portion and a stopper piece that extends outward so as to be wider continuously are provided on the constricted portion, and the cassette body restricts the opening of the stopper piece. An ink ribbon cassette for a printer, characterized in that a restriction wall is provided, and the opening of the end of the stopper piece when the small-diameter part passes through the constricted part is restricted by the restriction wall. 2. The ink ribbon cassette for a printer according to claim 1, wherein the pair of sandwiching pieces of the elastic member engages with the small diameter portion of the spool shaft to urge the spool shaft in the axial direction. Ink ribbon cassette for printers. 3. The ink ribbon cassette of the printer according to claim 1, wherein the cassette body is provided with a positioning means for positioning the elastic member.