JPS627502Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a driving connection between a printing mechanism and a ribbon cartridge of a printing device using a ribbon cartridge.

A ribbon cartridge is used in which an endless ribbon is stored in an irregular shape and a free span section is equipped with a printing wheel, a hammer, etc., and the ribbon taken out from the storage chamber is fed under tension. This ribbon cartridge is provided with rollers at the exit and entrance of the storage chamber for feeding the ribbon, and these rollers are driven by a ribbon motor provided in the main body of the printing mechanism. When the ribbon cartridge is attached to the main body of the printing mechanism, the motor shaft of the ribbon motor is drivingly connected to the drive roller shaft of the ribbon cartridge.

For example, when the ribbon cartridge stores two-color ribbons of black and red and performs two-color printing, it is necessary to move the free span portion by the positional difference between the black stripe portion and the red stripe portion of the ribbon. Therefore, the ribbon cartridge itself must move by the above positional difference when switching printing colors. Moreover, regardless of this movement, it is necessary to maintain the driving connection between the ribbon motor, which is the main component of the printing mechanism, and the drive roller of the ribbon cartridge.

A recess is formed at the lower end of the drive roller of the ribbon cartridge, and a member attached to the intermediate gear of the drive coupling mechanism that elastically escapes only in the axial direction is engaged with the recess to feed the ribbon, and further switch between red and black. A drive connection is used which maintains a drive connection between the intermediate gear and the ribbon motor for driving the intermediate gear and the drive roller of the cartridge when performing motion or character visibility motion.

In this driving coupling mechanism, the driving member, that is, the ribbon motor, etc., is also caused to swing vertically along with the ribbon cartridge, so a considerable amount of force is required for the swinging motion of the ribbon cartridge, and a large magnet, etc., is required. The weight will increase. Therefore, high-speed printing is hindered. In this case, if a driving member such as a ribbon motor is mounted near the center of the vertical swing of the ribbon cartridge, the swinging force can be reduced, but this is often difficult to realize mechanically. Furthermore, if the recess at the lower end of the drive roller of the ribbon cartridge and the axially movable member of the intermediate gear are not on the same line, the rotation of the ribbon motor will be transmitted irregularly and the ribbon will not be fed properly. become a rule,
A problem arises in that printing shading occurs. Furthermore, since the input lead wire to the ribbon motor moves together with the vertical swinging motion of the ribbon cartridge, there is a risk of the wire breaking due to bending fatigue, so it is necessary to use a special wire material to prevent the wire from breaking.

As a drive coupling mechanism, components that can move only in the direction perpendicular to the shaft and members that can escape only in the axial direction are attached to the intermediate gear that is coupled to the drive shaft of the ribbon motor, so that even if misalignment of each axis occurs, the ribbon There is also a mechanism that allows ribbon feeding of the cartridge.

This mechanism can compensate for some misalignment of each axis, but since it is approximately an Oldham mechanism, there is a problem in that smooth rotation of the drive roller cannot be obtained. Moreover, since the number of structural members is increased and sliding members are required, there is a problem of lack of durability.

An object of the present invention is to provide a printing device using a ribbon cartridge with a new configuration that allows reliable rotation with simple components.

The details of the present invention will be explained with reference to the drawings with reference to embodiments.

In FIGS. 1 and 2, an endless ribbon 2 stored in a ribbon cartridge 1 in an irregular shape is fed out by a drive roller 3. As shown in FIGS. The drive roller 3 is a first drive rotating body rotatably supported by a bearing 4 attached to the ribbon cartridge 1.
It has a drive shaft 5, a driven shaft 6, and rollers 7, 8 supported by the first drive shaft 5 and driven shaft 6, respectively, pressed against each other, and feeding the ribbon 2 with the ribbon 2 sandwiched between them. An engagement groove 9 is formed at the lower end of the first drive shaft 5 .

The ribbon cartridge 1 is supported so as to be vertically swingable around a support shaft 11 by a support base 10 which is integrally or removably formed as a support means.

A ribbon motor 12 for driving the drive roller 3 is fixed to a bracket 13 attached to the machine frame of the printing device, and a drive gear 14 is fixed to the drive shaft. Intermediate gear 1 meshing with drive gear 14
5 is fixed to a second drive shaft 17 as a second drive rotary body which is rotationally supported by a bearing 16 attached to the bracket 13. Therefore, the second drive shaft 17 serving as the second drive rotation body does not move as the ribbon cartridge 1 swings. A drive spring 18 is attached to the second drive shaft 17 and has one end engaged with the second drive shaft 17 or the intermediate gear. The other end of the drive spring 18 is an engagement protrusion, for example, which has enough rigidity to engage the engagement groove 9 of the first drive shaft 5 and reliably transmit the rotation of the second drive shaft 17 to the first drive shaft 5. It is formed as a hook portion 18a. Length of second drive shaft 17 and second drive shaft 1
Although the diameter of the helical winding of the drive spring 18 attached to the drive spring 7 is slightly bent with respect to the axis in response to the misalignment of the first drive shaft 5 due to the swinging of the ribbon cartridge 1, the rotation of the second drive shaft 17 is It is selected to the extent that it can be transmitted faithfully to the first drive shaft 5. That is,
The drive spring 18 can swing laterally and can transmit the rotation of the second drive shaft 17 to the first drive shaft 5. It is therefore formed as a fairly strong spring.

Drive roller 3 when installing ribbon cartridge 1
The engagement groove 9 of the first drive shaft 5 and the drive spring 18
If the hook portions 18a do not match, the drive spring 18 will be compressed in the axial direction as shown in FIG. In this state, by manually rotating the drive roller 3 or the intermediate gear 15, or by rotating the ribbon motor 1.
2 provides relative rotation between the drive spring 18 and the first drive shaft 5. When the hook portion 18a and the engagement groove 9 match, the hook portion 18a fits into the engagement groove 9 as shown in FIG.
Thereafter, the rotation of the second drive shaft 17 is transmitted to the first drive shaft 5, and the drive roller 3 rotates smoothly.

When the ribbon cartridge 1 is tilted as in the case of switching between black and red ribbon 2, the first drive shaft 5
The relative positions of the first drive shaft 5 and the second drive shaft 17 are selected in advance so that the hook portion 18a can be engaged with the engagement groove 9, although a misalignment occurs between the axis of the first drive shaft 5 and the axis of the second drive shaft 17. Therefore, the drive spring 18 is slightly bent in the vicinity of the hook portion 18a.
and the first drive shaft 5 is a shaft 17 as shown in FIG.
Even if the ribbon cartridge 9 does not move together with the ribbon cartridge 9, the engaged state can be maintained reliably. Therefore, irrespective of the tilted position of the ribbon cartridge 1, the drive connection between the intermediate gear and the drive roller is reliably maintained.

In the present invention, in a printing device using a ribbon cartridge, the first driving rotary body of the ribbon cartridge and the second driving rotary body provided in the printing mechanism are drivingly connected by a drive spring that can swing laterally. Therefore, even if the ribbon cartridge swings, the drive connection can be prevented from becoming disconnected.

Therefore, irregular ribbon feeding can be avoided, and a printing device that can print clearly can be obtained.

In contrast to the example shown in the figures, it is also possible to attach a member having an engagement groove to the tip of the drive spring and form an engagement protrusion at the tip of the first drive shaft.

[Brief explanation of the drawing]

Figure 1 is an exploded perspective view of the mechanism according to the present invention;
The figure is a partial side view, Figure 3 is a diagram showing the intermediate gear and the drive roller in a drive uncoupled state, Figure 4 is a diagram showing the drive connection state compared to Figure 3, and Figure 5 is a diagram when the cartridge is tilted. It is a figure which shows a drive connection state. 1... Ribbon cartridge, 2... Ribbon, 3
... Drive roller, 5 ... First drive shaft, 7 ... Roller, 9 ... Engagement groove, 12 ... Ribbon motor, 15
... Intermediate gear, 17 ... Second drive shaft, 18 ... Drive spring, 18a ... Engagement protrusion (hook part).

Claims (1)

[Claims for Utility Model Registration] (1) A ribbon cartridge that accommodates a ribbon therein, a first driving rotor provided in the ribbon cartridge for feeding the ribbon, and a first drive rotor that is capable of swinging the ribbon cartridge. a second drive rotor provided in the printing mechanism and which does not move with the swinging of the ribbon cartridge; and a lateral rocker for drivingly connecting the first drive rotor and the second drive rotor. A printing device using a ribbon cartridge, characterized in that a movable drive spring is provided, and the first drive rotor is rotated by the second drive rotor. (2) A printing device using a ribbon cartridge according to claim 1, wherein the drive spring is expandable and retractable in the axial direction.