JPH03211075A - Ink ribbon winding mechanism - Google Patents

Abstract

PURPOSE:To prevent the overslip of a friction clutch by providing the second rotating element to which a drive power transmitted to the first rotating element, is transmitted through a friction material and a reel stand when in the printing mode and a lock mechanism for rotating the first rotating element and the second rotating element in one piece when in the non-printing mode. CONSTITUTION:A reel stand 5 rotates in a state in which it is slightly braked by a friction clutch 12 when in the printing mode because a drive power is transmitted to a reel stand 5 through the friction clutch 12. In addition, a switching gear 22 idles in a state where it engages with the gear part 17 of a brake plate 14. Thus an appropriate tension is given by the sliding friction of the friction clutch 12 and therefore, a slack in an ink ribbon 1 can be eliminated during a printing process. If a printer is set in the non-printing mode, the one end 30 of a switching lever 25 moves the switching gear 22 in an arrow Y direction resisting the energization force of a return spring 24. Consequently, the switching gear 22 engages with the gear part 17 of the braking plate 14 and a clutch gear 13 and the friction clutch 12 is locked.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an ink ribbon winding mechanism, particularly an ink ribbon winding mechanism suitable for a thermal transfer (sublimation type) printer.

[Summary of the invention]

In an ink ribbon winding mechanism, the present invention includes a first rotary body to which a driving force is transmitted from a drive source, and a first rotary body disposed coaxially with the first rotary body through a friction material. The second rotating body and the reel stand, to which the driving force transmitted to the rotating body is transmitted via the friction material, and the first rotating body and the second rotating body are rotated integrally when not printing. With this locking mechanism, the required performance for the torque range of the friction clutch can be relaxed, and the ink ribbon can be reliably fed rapidly, even when the winding diameter ratio is large. It is designed to be rolled up.

[Conventional technology]

An example of a conventional thermal transfer (sublimation) printer that prints in color with a print head by bringing photographic paper into contact with a platen and using an ink ribbon in a ribbon cartridge is as follows.
There is one as shown in Japanese Patent Application Laid-Open No. 1-249486.

An example of an ink ribbon winding mechanism in a conventional thermal transfer (sublimation type) printer is shown in FIG.

In the configuration shown in FIG. 5, the end portion 53 of the ribbon reel 52 on which the ink ribbon 51 is wound is provided with an annular piece 54 for preventing the ink ribbon 51 from shifting during winding, and a reel stand 55. A recess 56 is formed for inserting.

A plurality of protrusions 58 are formed in the recess 56 to engage with a locking body 57 attached to the reel stand 55 to prevent the ribbon reel 52 from spinning idly.

The reel stand 55 is provided on the main body side of the printer and is fixed to a shaft 59. A tip 60 is formed on the ribbon reel 52 side of the reel stand 55, and a spring presser 61 is formed on the opposite side of the reel stand 55 from the ribbon reel 52 in the direction of arrow X. A friction clutch 62 is constructed between the clutches 61 and 61 .

The tip portion 60 has a size that can be inserted into the recess 56 of the ribbon reel 52, and a locking member is provided on the outside of the tip portion 60 to engage with the protruding strip 58 in the recess 56 to prevent idle rotation. A plurality of stoppers 57 are provided.

The friction clutch 62 connects the reel stand 55 and the clutch gear 6.
3, brake plate 64, coil spring 65, and friction material 6
It consists of 6. A friction material 66 such as felt is provided between the clutch gear 63 and the reel stand 55 and between the clutch gear 63 and the brake plate 64.
are arranged.

The above-mentioned coil spring 65 is disposed between the spring presser 61 and the brake plate 64, and biases the brake plate 64 toward the clutch gear 63 in the direction of arrow Y. This brake plate 64 can only move in the thrust direction relative to the reel stand 55.

Friction clutch 62 constitutes a torque limiter.

That is, between the clutch gear 63, the reel stand 55, and the brake plate 64, frictional resistance due to sliding friction is generated due to the pressing force of the coil spring 65 and the action of the friction material 66, thereby forming a torque limiter. Ru.

Since driving force is transmitted from a motor (not shown) to the reel stand 55 via the drive gear 67 and the clutch gear 63, the reel stand 55 rotates while being lightly braked by the friction clutch 62.

[Problem to be solved by the invention]

The conventional ink ribbon winding mechanism as described above transmits driving force to the reel stand 55 via the friction clutch 62, drives the ribbon reel 52, and winds the ink ribbon during printing or non-printing. It was configured to wind up 51 pieces.

In such a configuration, strict performance conditions regarding the torque range of the friction clutch 62 are required. In other words, when printing, it is sufficient to consider a torque range that is sufficient to remove the slack in the ink ribbon 51 fed by the platen without affecting the rotation of the platen (not shown), whereas when not printing, the ink ribbon 51 is wound. The torque range must be considered so that the friction clutch 62 does not slip too much when the clutch is released. Of course, when printing and when not printing,
Although different torque ranges are required, both must be compatible.

Conventionally, there has been a problem that the ink ribbon 51 may not be able to be wound up due to excessive slippage of the friction clutch 62 during non-printing.

Furthermore, the winding diameter of the ink ribbon 51 on the ribbon reel 52 changes between the beginning and the end of winding, but the above torque range is based on the winding diameter ratio (the diameter of the ribbon reel 52 and the winding of the ink ribbon 51). It must also be able to respond to changes in the diameter (ratio of diameter at time).

Conventionally, when this winding diameter ratio is large, the friction clutch 62
There is a problem that the ink ribbon 51 tends to slip and the ink ribbon 51 may not be fed.

Therefore, an object of the present invention is to provide an ink ribbon winding mechanism that can apply appropriate tension to the ink ribbon during printing and appropriately wind the ink ribbon when not printing.

[Means to solve the problem]

In this invention, a first rotary body to which driving force is transmitted from a drive source, and a first rotary body disposed coaxially with the first rotary body via a friction material,
At the time of printing, the driving force transmitted to the first rotating body is transmitted to the second rotating body and the reel stand through the friction material, and the first rotating body
The structure includes a lock mechanism for rotating the rotating body and the second rotating body integrally during non-printing.

[Effect]

Driving force is transmitted from the driving source to the first rotating body.

During printing, the driving force transmitted to the first rotating body is transmitted to the second rotating body and the reel stand via the friction material.

Therefore, the friction clutch is driven by sliding friction.

When not printing, the lock mechanism locks the first rotating body and the second rotating body.
The rotating bodies are locked and rotate as one unit. Thereby, the driving force supplied to the first rotating body is directly transmitted to the reel stand.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 4. This embodiment describes an example in which an ink ribbon winding mechanism is applied to a thermal transfer (sublimation type) printer. Further, in this embodiment, it is assumed that the ribbon reels on the supply side and take-up side and the ink ribbon are configured as a ribbon cartridge.

In the configuration shown in FIG. 1, the end portion 3 of the ribbon reel 2 on which the ink ribbon 1 is wound is provided with an annular piece 4 for preventing the ink ribbon 1 from shifting during winding, and a reel stand 5. A recess 6 is formed for inserting.

A plurality of protrusions 8 are formed in the recess 6 to engage with a locking body 7 attached to the reel stand 5 and to prevent the ribbon reel 2 from spinning idly.

The reel stand 5 is provided on the main body side of the printer and is fixed to the shaft 9. A tip 10 is formed on the ribbon reel 2 side of the reel stand 5, and a spring retainer 11 is formed on the opposite side of the reel stand 5 from the ribbon reel 2 in the direction of arrow X.
A friction latch 12 is formed between the tip 10 and the spring retainer 11.

The tip 10 is sized to be inserted into the recess 6 of the ribbon reel 2, and the tip 10 has a recess 6 on the outside.
A plurality of locking bodies 7 are provided for locking with the inner convex strip 8 to prevent idle rotation.

The friction clutch 12 includes a reel stand 5, a clutch gear 13 as a first rotating body, a brake plate 14 as a second rotating body, a coil spring 15, and a friction material 16. A friction material 16 such as felt, for example, is arranged between the clutch gear 13 and the reel stand 5 and between the clutch gear 13 and the brake plate 14.

Further, the above-mentioned coil spring 15 is disposed between the spring retainer 11 and the brake plate 14, and urges the brake plate 14 toward the clutch gear 13 in the direction of arrow Y. This brake plate 14 is configured to be movable only in the thrust direction with respect to the reel stand 5, and a gear portion 1 is provided on the outer periphery of the brake plate 14.
7 is formed.

Friction clutch 12 constitutes a torque limiter.

That is, between the clutch gear 13, the reel stand 5, and the brake plate 14, frictional resistance due to sliding friction is generated due to the pressing force of the coil spring 15 and the action of the friction material 16, thereby forming a torque limiter. Ru.

A lock mechanism 20 is provided near the friction clutch 12. This locking mechanism 20 is for switching the friction clutch 12 between a locked state and an unlocked state during printing and non-printing.

As shown in FIG. 1, the lock mechanism 20 includes a gear support 21 provided near the friction clutch 12 and a switching gear 22 coaxially attached to the gear support 21.
, the return spring 24 which is disposed between the spring presser 23 of the gear support 21 and the switching gear 22 and biasing the switching gear 22 in the direction of the arrow X, and the position of the switching gear 22 when printing. It consists of a switching lever 25 for switching between printing and non-printing, and a cam 28 provided on the head crimp shaft 26.

0 The above-described switching lever 25 is for changing the position of the switching gear 22 in the X and Y directions by the cam of the head crimping shaft 26 shown in FIGS. 1 and 3. By rotating the shaft 26 in the direction of arrow A, the positions of one end 30 and the other end 31 of the switching lever 25 change to the shaft 29.
It is structured so that it changes around the fulcrum. One end 30 of the switching lever 25 is in contact with the lower surface 32 of the switching gear 22, and the other end 31 is in contact with the upper surface 33 of the disc 27 of the head crimp shaft 26. Incidentally, this head pressure-bonding shaft 26 is configured not to move during printing and is configured to maintain the state shown in FIG. 1.

Printed portion 35 is shown in FIG.

Rollers 37, 38 are provided around the outer periphery of the platen 36, and the photographic paper 39 is wound around the platen 36 and pressed by these rollers 37, 38.

On the other hand, the print head 40 is fixed to a support 41, and the support 41 is rotatable in the directions of arrows T and IT via a shaft 42. Further, the shaft 43 of the support body 41 and the head pressure bonding shaft 26 are connected by a link 44, and the support body 41 is rotated by the link 44.

Accordingly, the rotation of the head pressure shaft 26 causes the print head 40 to rotate in the direction of arrow T during printing, and presses the ink ribbon 1 against the photographic paper 39 wound around the platen 36. Furthermore, when not printing, the link 44 is actuated by the rotation of the head crimp shaft 26, and the print head 40 is rotated in the direction of the arrow IT force.

At this time, the ink ribbon 1 separates from the photographic paper 39 wound around the platen 36 and returns to the position shown by the two-dot chain line in the figure.

Next, the operation during printing will be explained with reference to FIG. In this embodiment, the mechanism is operated under the control of a system controller (not shown).

When printing, as shown in FIG.
Since the other end 31 of 5 is located on the upper surface 33 of the disc 27, the switching gear 22 meshes with the gear portion 17 of the brake plate 14.

In this case, the driving force is transmitted via the friction clutch 12,
Since the signal is transmitted to the reel stand 5, the reel stand 5 rotates while being lightly braked by the friction clutch 12. Further, the above-mentioned switching gear 22 idles while being meshed with the gear portion 17 of the brake plate 14.

In this way, during printing, an appropriate tension can be applied by the sliding friction of the friction clutch 12, and slack in the ink ribbon 1 can be removed.

Next, with reference to FIG. 4, the operation of the mechanism during non-printing, for example, when the ink ribbon is rapidly fed, will be described.

When not printing, the print head 40 is not pressed against the platen 36, so as shown in FIG. 4, the head press shaft 26 rotates and the cam 28 moves to the illustrated position. As a result, the other end 31 of the switching lever 25 is located on the upper surface 34 of the convex portion 35 of the cam 28, and the switching lever 25 is positioned on the shaft 2.
It rotates around 9 as a fulcrum. As a result, the one end 30 of the switching lever 25 moves the switching gear 22 in the direction of arrow Y against the biasing force of the return spring 24.

Therefore, the switching gear 22 is connected to the gear portion 1 of the brake plate 14.
7 and clutch gear 13, and the friction clutch 12 is in a locked state.

In this case, the driving force is transmitted to the reel stand 5 via the drive gear 18 and the clutch gear 13.

As described above, since the friction clutch 12 is locked, the brake plate 14, clutch gear 13, and reel stand 5 rotate integrally. Therefore, the driving force supplied from the motor (not shown) is directly transmitted to the reel stand 5 and the ribbon reel 2.

In this way, since the friction clutch 12 is locked during non-printing, there is no need to consider an excessive torque range for the friction clutch 12, and the required performance of the friction clutch 12 can be relaxed.

Also, when not printing, for example, when the ink ribbon is fast-forwarding,
Excessive slippage of the friction clutch 12 can be prevented, and the ink ribbon 1 can be reliably fed.

Furthermore, since the friction clutch 12 is in a locked state, even if the winding diameter ratio becomes large, the friction clutch 12 is prevented from slipping too much, and the ink ribbon 1 can be reliably wound.

Although this embodiment is explained using a thermal transfer (sublimation type) printer as an example, it is not limited to this, and any printer that uses the friction clutch 12 to wind up the ink ribbon 1 can be used. Applicable to all printers.

Further, in this embodiment, the clutch gear 13 and the brake plate 14 are locked by the switching gear 22, but the invention is not limited to this, and any configuration can be used. It may also be locked.

Furthermore, although this embodiment explains that the operation is controlled by the system controller, the system controller is not limited to this, and the same function can be achieved by a mechanical configuration or an electronic circuit configuration. You may.

〔Effect of the invention〕

5 According to this invention, since the friction clutch is locked by the locking mechanism when not printing, it is only necessary to mainly consider the torque range during printing, and there is no need to consider an unnecessary torque range. Therefore, there is an effect that the performance required for the torque range of the friction clutch can be relaxed.

Also, when not printing, for example, when the ink ribbon is fast-forwarding,
This has the effect of preventing the friction clutch from slipping too much and ensuring reliable feeding of the ink ribbon.

Furthermore, since the friction clutch is in a locked state, even if the winding diameter ratio becomes large, the friction clutch is prevented from slipping too much, and the ink ribbon can be reliably wound.

[Brief explanation of drawings]

Fig. 1 is a sectional view showing an embodiment of the present invention, Fig. 2 is a configuration diagram illustrating the main parts of the printing part, Fig. 3 is a plan view illustrating the cam, and Fig. 4 is an embodiment of the invention. A cross-sectional view showing the operation of the mechanism during rapid forwarding of the ink ribbon in the example, No. 5
The figure is a sectional view illustrating a conventional example. Explanation of main symbols in the drawings 1.51: Ink ribbon, 2.52: Ribbon reel, 5
．． 55: Reel stand, 12.62: Friction clutch, 13.
63: Clutch gear, 14.64 Brake plate, 16.
66: Friction material, 20: Port/link mechanism, 21: Gear support, 22: Switching gear, 25: Switching lever, 28: Cam.

Claims (1)

[Scope of Claims] A first rotating body to which driving force is transmitted from a drive source; and a first rotating body disposed coaxially with the first rotating body through a friction material, and during printing, the driving force is transmitted to the first rotating body. a second rotary body and a reel stand to which a driving force is transmitted via a friction material; and a lock mechanism for integrally rotating the first rotary body and the second rotary body when not printing. An ink ribbon winding mechanism characterized by comprising: