JP3017410B2 - Printing device ribbon cassette - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ribbon cassette for a printing apparatus.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 7, as shown in FIG. 8, inside a cassette case 2 in which an endless ink ribbon 1 partly pulled out from the front of a print head (not shown) is stored. There is a ribbon cassette in which a ribbon winding gear 3 and a driven gear 4 are rotatably provided. Both ends of the ribbon take-up gear 3 are exposed from the cassette case 2, and when the cassette case 2 is attached to the printing apparatus, as shown in FIG.
Are connected at one end. In some cases, an ink pad for supplying ink to the ink ribbon 1 is provided in the cassette case 2. However, if the ink ribbon 1 is used for a certain period of time, the ink becomes weak and the ink ribbon 1 itself hurts. There is a need.

[0003]

As shown in FIG. 8, the ribbon take-up gear 3 and the driven gear 4 have a large number of teeth 3a,
Since the ink ribbon 1 is sandwiched with the ink ribbon 1a, the ink ribbon 1 pulled into the cassette case 2 from the front of the print head is folded in a zigzag and stored in a packed state. Therefore, during a long use period, the ink ribbon 1 may be clogged in the cassette case 2 or a ribbon jam may occur due to the ink ribbon 1 being caught by some member in a traveling path. When the ribbon jam occurs, a large load is applied to the ribbon winding gear 3 because the ink ribbon 1 does not move, and if the load exceeds a certain value, the ribbon drive shaft 5 of the printing apparatus may be broken. In this case, since the printing device needs to be repaired, the printing operation cannot be continued, and the maintenance cost also increases.

[0004]

According to the first aspect of the present invention,
A cassette case detachably mounted to the printing apparatus, an endless ink ribbon housed in the cassette case and partially pulled out to the front of the print head, and a cassette case rotatably held inside the cassette case. A ribbon take-up gear and a driven gear that have a number of teeth on an outer periphery thereof and take up the ink ribbon; and a ribbon drive shaft of the printing device that is detachably provided in the ribbon take-up gear from one direction. The engaging portion to be fitted and the inner peripheral surface of the ribbon take- up gear are attached to the ribbon take-up gear.
And a power transmission means having a connection portion which is connected to the formed groove and has a strength determined to such an extent that it is broken when a load corresponding to the occurrence of the ribbon jam is applied. . Invention of claim 2
Is the ribbon cassette according to claim 1, wherein power transmission is performed.
The means comprises an opening at both ends and the ribbon from any direction.
It is set in a removable shape inside the take-up gear.
In the ribbon take-up gear even from this direction.
Connected to the groove formed on the inner peripheral surface of the ribbon take-up gear
Printing with a connecting part at a position to be connected and a position not to be connected
It is a ribbon cassette of an apparatus.

[0005]

According to the present invention, the rotation of the ribbon drive shaft is normally transmitted to the ribbon winding gear via the engaging portion and the connecting portion of the power transmitting means. If the ribbon jam took high load the ribbon take-up gear occurs, maintained since the consolidated portion of the power transmission means is destroyed, the power transmission interrupted state between the ribbon drive shaft and the ribbon take-up gear Is done. Power transmission means
According to the invention described in claim 2, when the joint is broken,
Reverse the power transmission means to the ribbon take-up gear and
Power transmission means by attaching it to the ribbon take-up gear.
Can be used.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described with reference to FIGS. The same parts as those described in FIGS. 7 to 9 are denoted by the same reference numerals, and description thereof is omitted (the same applies hereinafter). FIG. 1 is a longitudinal sectional side view showing a part of the cassette case 2. On the bottom surface 6 of the cassette case 2, a fitting for rotatably holding a lower end of a ribbon take-up gear 7 having a plurality of teeth 3 a formed on the outer periphery. A mating portion 8 and an insertion hole 9 which is provided at the center of the fitting portion 8 and through which the ribbon drive shaft 5 on the printing apparatus side is inserted are formed. The cover 10 of the cassette case 2 is formed with a fitting hole 12 for projecting a knob 11 formed at the upper end of the ribbon winding gear 7.

The ribbon take-up gear 7 is provided with power transmission means 13 driven by the ribbon drive shaft 5. The power transmission means 13 is formed in a cylindrical shape having both ends open, and an inner peripheral portion thereof has an engaging portion which engages with the ribbon drive shaft 5 having a cross-shaped cross section such as a tool driver. A plurality of ribs 14 are integrally formed, and a plurality of pin-shaped connecting portions that are selectively connected to grooves 15 formed on the inner peripheral surface of the ribbon winding gear 7 at both ends of the outer peripheral surface. The protrusion 16 is formed integrally. The strength of these protrusions 16 is determined to such an extent that the protrusions 16 are broken when a load corresponding to the occurrence of ribbon jam is applied. That is, the rotation torque of the ribbon take-up gear 7 normally required for running the ink ribbon 1 is t, the torque (∞) for rotating the ribbon take-up gear 7 when a ribbon jam occurs is T, Assuming that the breaking torque of the section 16 is T1 and the breaking torque of the ribbon drive shaft 5 of the printing apparatus is T2, t <
The relationship is defined as T1 <T2, T> T1 <T2.

In such a configuration, when the cassette case 2 is mounted on the printing device, the power transmission means 13 is connected to the ribbon drive shaft 5. When the ribbon drive shaft 5 is driven in this state, the power transmission means 13 rotates. In a normal state in which the ribbon jam does not occur, the rotation of the power transmission means 13 is restricted by the groove 15 and the protrusion
The ink ribbon 1 is transmitted to the ribbon winding gear 7 by the engagement with the ribbon winding gear 6.

If a ribbon jam occurs due to the ink ribbon 1 clogging inside the cassette case 2 or the like, the projection 16 of the power transmission means 13 is broken due to the relationship of T> T1 <T2 described above. Although the occurrence frequency of the ribbon jam is not particularly large enough to break the power transmission means 13 in this way, it can be dealt with by exchanging the ribbon cassette as a consumable, so that the ribbon driving shaft of the printing apparatus is used. 5
Can be eliminated, and the cost for maintenance can be eliminated.

In this embodiment, the projection 16 of the power transmission means 13 is formed at one end as shown in FIG.
When only the protrusion 16 is broken, the cover 10 of the cassette case 2 is opened, and the power transmission means 13 is turned upside down with respect to the ribbon winding gear 7 when only the projection 16 is broken. The power transmission is achieved by fitting the broken projection 16 downward and the new projection 16 upward to engage the groove 15 of the ribbon winding gear 7 again. Means 13 can be reused.

[0011]

Next, a second embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 4, the driven gear 4 and the ribbon take-up gear 17 are rotatably provided in the cassette case 2, and an ink reservoir 18 is provided. The ink reservoir 18 has an ink roller 19 for supplying ink impregnated in a sponge or the like to the ribbon winding gear 17. Further, when the ink ribbon 1 is wound by the ribbon winding gear 17 and the driven gear 4, a leaf spring 20 that presses the ink ribbon 1 against the cassette in order to apply tension to the ink ribbon 1 drawn out to the cassette case 2. The case 2 is provided.

As shown in FIGS. 5 and 6, the power transmission means 21 in this embodiment comprises a rib 14 engaged with the ribbon drive shaft 5 and a groove 1 formed on the inner periphery of the ribbon take-up gear 17.
5 and a knob 11 penetrated by the ribbon take-up gear 17 and protruding from the fitting hole 12 of the case 2.

In such a configuration, when the cassette case 2 is mounted on the printing apparatus and the ribbon drive shaft 5 is driven, the power transmission means 21 rotates. When a ribbon jam occurs due to the ink ribbon 1 clogging inside the cassette case 2 or the like, the projection 16 of the power transmission means 21 is broken.

The ribbon cassette applied to the present invention is applicable to both a cassette mounted on a carriage on which a print head is mounted and a ribbon cassette fixed separately from the carriage.

[0016]

According to the first aspect of the present invention, the engaging portion engaged with the ribbon drive shaft of the printing apparatus and the ribbon take-up gear.
Formed on the inner peripheral surface of the ribbon take-up gear
When a load corresponding to the occurrence of a ribbon jam is applied to the ribbon take-up gear, a power transmission means having a connection portion whose strength is determined to such a degree that the ribbon is broken is disposed in the ribbon take-up gear.
Since it is provided detachably from the direction , usually, the rotation of the ribbon drive shaft is transmitted to the ribbon take-up gear via the engagement portion and the connection portion of the power transmission means, and ribbon jam occurs and the ribbon take-up gear when a high load is applied, since the consolidated portion of the power transmission means is destroyed, can be maintained between the ribbon drive shaft and the ribbon take-up gear to the power transmission interrupted state, thereby, the printing device This prevents the ribbon drive shaft on the side from being destroyed, eliminates the hassle of replacing the ribbon drive shaft of the printing device, and eliminates the cost required for maintenance. Claim 2
According to the described invention, the power transmission means is open at both ends.
Removable shape inside the ribbon take-up gear from any direction
And ribbon winding from any direction
While mounted inside the gear, it is formed on the inner peripheral surface of the ribbon take-up gear.
Between the position where it is connected to the formed groove and the position where it is not connected.
With the connection, the connection of the power transmission means is broken.
Power transmission means in the reverse direction with respect to the ribbon take-up gear
Power transmission by attaching it to the ribbon take-up gear
Means can be reused.

[Brief description of the drawings]

FIG. 1 is a vertical sectional side view showing a relationship among a ribbon drive shaft, a power transmission means, and a ribbon winding gear according to a first embodiment of the present invention.

FIG. 2 is a horizontal sectional view showing a relationship between a power transmission means and a ribbon winding gear.

FIG. 3 is an exploded perspective view showing a relationship among a ribbon drive shaft, a power transmission means, and a ribbon winding gear.

FIG. 4 is a plan view showing the inside of a cassette case according to a second embodiment of the present invention.

FIG. 5 is a vertical sectional side view showing a relationship between a power transmission means and a ribbon winding gear.

FIG. 6 is a horizontal sectional view showing the relationship between the power transmission means and the ribbon take-up gear.

FIG. 7 is a perspective view showing the appearance of a conventional ribbon cassette.

FIG. 8 is a partial plan view showing the winding operation of the ink ribbon.

FIG. 9 is an exploded perspective view showing a relationship between a ribbon winding gear and a ribbon drive shaft.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Ink ribbon 2 Cassette case 3a, 4a Teeth 4 Follower gear 5 Ribbon drive shaft 7 Ribbon winding gear 13 Power transmission means 14 Engagement part 15 Groove 16 Connection part 17 Ribbon winding gear 21 Power transmission means

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B41J 35/36 B41J 32/00

Claims (2)

(57) [Claims] 1. A cassette case removably mounted on a printing apparatus, an endless ink ribbon housed in the cassette case and partially drawn out to the front of a print head, and a rotatable interior of the cassette case. A ribbon take-up gear and a driven gear that are held and have a number of teeth on an outer peripheral portion thereof and take up the ink ribbon; and a ribbon take-up gear that is detachably provided in the ribbon take-up gear from one direction . An engagement portion engaged with the ribbon drive shaft and a ribbon take-up gear associated with the attachment to the ribbon take-up gear ;
And a power transmission means having a connection part which is connected to a groove formed on the inner peripheral surface of the hook and has a strength determined to such an extent that it is broken when a load corresponding to the occurrence of the ribbon jam is applied. Characteristic ribbon cassette for printing equipment. 2. The power transmission means, wherein both ends are open.
To be removable in the ribbon take-up gear
And the ribbon winding from any direction.
The inner circumference of the ribbon take-up gear in a state of being mounted in the take-up gear.
The position connected to the groove formed on the surface and the position not connected
The seal according to claim 1, further comprising a connecting portion.
Ribbon cassette for character unit.