JP2008230093A - Recording device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a recording device that properly handles ribbon locking without providing a connecting part while preventing an ink ribbon cartridge from drop out even when a ribbon winding shaft receives a force that pushes out a ribbon winding roller. <P>SOLUTION: A female screw part of a ribbon winding roller 45 provided in an ink ribbon cartridge 29 is fitted with a male screw part of a ribbon winding shaft 47. The ribbon winding shaft 47 is driven so as to allow an ink ribbon to be windable by the ribbon winding roller 45. The rigidity of the female screw part is formed weaker than that of the male screw part so that the female screw part of the ribbon winding roller 45 is formed to be breakable when an excessive load is applied. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a recording apparatus having a mechanism for driving a ribbon winding shaft and winding an ink ribbon by a ribbon winding roller.

  In general, a dot impact printer is known in which a recording head mounted on a carriage is provided with a plurality of recording wires and an image is recorded on a recording medium via an ink ribbon by the protruding operation of these recording wires. A conventional dot impact printer of this type includes a ribbon drive mechanism that winds up an ink ribbon in both directions of carriage movement using, for example, power when the carriage reciprocates. The ribbon drive mechanism includes a mechanism for winding a ribbon. The mechanism includes a male screw portion of a ribbon take-up shaft fitted to a female screw portion of a ribbon take-up roller provided in an ink ribbon cartridge, and the ribbon take-up shaft Is generally used, and an ink ribbon is taken up by a ribbon take-up roller (see, for example, Patent Document 1).

In the above configuration, a structurally weak connecting portion is interposed between the ribbon take-up shaft and the ribbon take-up roller, and when the force for pushing the ribbon take-up roller is applied to the ribbon take-up shaft by the ribbon lock, the connecting portion is damaged. A technique has been proposed (see, for example, Patent Document 2).
JP 2004-330516 A JP-A-8-72374

However, in the conventional configuration, the number of components increases by providing the connecting portion, and the work of mounting the ink ribbon cartridge becomes difficult by providing the connecting portion.
Also, depending on the ink ribbon cartridge mounting structure, the ink ribbon cartridge may drop out before the connecting portion is damaged, which may adversely affect other devices of the dot impact printer.

  Accordingly, the object of the present invention is to solve the above-described problems of the prior art, appropriately deal with ribbon lock without providing a connecting portion, and when a force for pushing out the ribbon take-up roller acts on the ribbon take-up shaft. Another object of the present invention is to provide a recording apparatus in which the ink ribbon cartridge does not fall off.

The present invention provides a recording apparatus that includes a plurality of recording wires in a recording head mounted on a carriage, and records an image on a recording medium via an ink ribbon from an ink ribbon cartridge by a protruding operation of these recording wires. The ribbon thread take-up roller can be wound around the internal thread part of the ribbon take-up roller provided in the ink ribbon cartridge, and the ribbon take-up shaft can be driven to wind the ink ribbon. The internal thread portion is formed to be less rigid than the external thread portion, and the internal thread portion is formed to be capable of being broken when an excessive load is applied.
In this case, the teeth of the female screw portion may be formed thinner than the teeth of the male screw portion so that the teeth can be lost with an excessive load.

In this invention, when an excessive load pushing the ribbon take-up roller acts on the ribbon take-up shaft due to the occurrence of the ribbon lock, the internal thread portion of the ribbon take-up roller provided in the ink ribbon cartridge is lost, and the ribbon take-up shaft is lost. And the power transmission between the ribbon take-up roller is cut off.
Accordingly, the ribbon lock is eliminated and the recording wire provided in the recording head can be prevented from being lost. In addition, since the ribbon take-up shaft can be prevented from being lost when the ribbon is locked, the printer main body is not repaired, and can be dealt with only by replacing the ink ribbon cartridge. Furthermore, the conventional connecting portion is not necessary, the number of parts is reduced, and the ink ribbon cartridge can be easily attached.

Moreover, the thickness of the tooth | gear of an internal thread part and an external thread part should just be the thickness of the tooth | gear of a meshing part. If the teeth of the female screw portion are formed thinner than the teeth of the male screw portion in the meshing portion, the same effect can be obtained.
Further, the ink ribbon cartridge may include an engagement piece that slides toward the support portion of the ink ribbon cartridge and that can be engaged with the support portion to prevent the ink ribbon cartridge from falling off the mounting portion. .
In the present invention, even when an excessive load pushing the ribbon take-up roller acts on the ribbon take-up shaft in the process in which the female thread side of the ribbon take-up roller is lost, the ribbon cartridge is prevented from falling off.

The engaging piece of the ink ribbon cartridge is spring-biased so that the tip of the engaging piece protrudes outward from the side edge of the ink ribbon cartridge, and when attached, the tip of the engaging piece resists the spring force. After the attachment, the tip of the engagement piece protrudes outward from the side edge by the spring force and engages with the support portion of the ink ribbon cartridge. Good.
Further, the support portion may be a locking hole formed in the side frame.
In these configurations, the engagement piece is slid to engage the support portion of the ink ribbon cartridge when the ink ribbon cartridge is mounted. This prevents the ink ribbon cartridge from falling off even when an excessive load that pushes the ribbon take-up roller acts on the ribbon take-up shaft.

In the present invention, the internal thread portion of the ribbon take-up roller is lost when the ribbon is locked, and the ribbon take-up shaft can be prevented from being lost, so that the printer main body is not repaired. No part is required, the number of parts is reduced, and the ink ribbon cartridge can be easily attached.
Further, when the ink ribbon cartridge is mounted, the engagement piece is slid and the engagement piece is engaged with the support portion of the ink ribbon cartridge, so that an excessive load that pushes the ribbon take-up roller to the ribbon take-up shaft is applied. Even when it acts, the ink ribbon cartridge is prevented from falling off the mounting portion.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a perspective view showing a front appearance of a printer 10 according to an embodiment of a recording apparatus of the present invention, FIG. 2 is a side sectional view of the printer 10, and FIGS. It is a perspective view which shows the frame structure of this.
The printer 10 includes a recording head 20 that selectively ejects a plurality of recording wires, and a carriage 21 on which the recording head 20 is mounted. The recording wire ejected from the recording head 20 is a recording medium (hereinafter referred to as a sheet). .) Is a serial dot impact printer that records an image including characters by striking. As shown in FIG. 2, this printer 10 is roughly divided into a printer main body 12, which constitutes a recording unit, a tractor unit 13, and a sheet guide 14. These upper and lower parts are as shown in FIG. Further, the upper case 15 and the lower case 16 are covered. The sheet includes a cut sheet cut to a predetermined length and a continuous sheet in which a plurality of sheets are connected. Examples of the cut sheet include a cut sheet, a copy paper, a passbook, and a cut film, and the continuous sheet includes a continuous sheet.

  The printer main body 12 includes a recording head 20, a carriage 21, and a platen 22 as a recording mechanism unit, and a plurality of conveying rollers 23 as a sheet conveying mechanism unit. More specifically, as shown in FIGS. 3 and 4, the printer main body 12 includes a back frame 27, a platen 22, a carriage shaft 28, a plurality of roller shafts 23 a, and a tractor unit 13 between a pair of side frames 25 and 26. The carriage shaft 28 is provided with a carriage 21, and each roller shaft 23 a is provided with a conveyance roller 23.

  The conveyance rollers 23 are arranged in pairs in the vertical direction in front of and behind the printer main body 12 with respect to the platen 22 (some conveyance rollers 23 are not shown), and a sheet conveyance motor (not shown) and the motor The drive wheel train 41 connected and arranged outside the right side frame 26 is rotationally driven clockwise or counterclockwise in FIG. Thus, the sheet can be conveyed from the front (sheet guide 14 side) of the printer main body 12 to the rear, and can be conveyed from the rear of the printer main body 12 to the front, and the sheet is orthogonal to the main scanning direction of the carriage 21. Is conveyed in the sub-scanning direction.

The carriage 21 is slidably inserted into the carriage shaft 28 and mounted on a timing belt 43 (see FIG. 3) mounted with a recording head 20 and driven by a carriage drive motor constituted by a stepping motor (not shown). Combined.
As a result, the carriage 21 is guided to the carriage shaft 28 via the timing belt 43 by the forward or reverse rotation of the carriage drive motor, and coincides with the axial direction of the carriage shaft 28 and the longitudinal direction of the platen 22. (Scanned). The recording head 20 includes a large number of recording wires (not shown), and drives these recording wires toward the platen 22.

As shown in FIG. 5, a stationery type ink ribbon cartridge 29 is detachably mounted on the printer main body 12, and the ink ribbon of the ink ribbon cartridge 29 is fed between the recording head 20 and the platen 22.
As a result, while the recording head 20 is traveling in the main scanning direction together with the carriage 21, these recording wires are projected and applied to the ink ribbon, and the ink on the ink ribbon is placed between the platen 22 and the recording head 20. An image containing characters is recorded on the sheet conveyed to the sheet. As shown in FIG. 3, a ribbon mask holder 51 is installed on the carriage 21, and the ribbon mask holder 51 is conveyed from the ink ribbon in the ink ribbon cartridge 29 in contact with the upper surface of the platen 20 ( The cut sheet or continuous sheet) is protected.

The tractor unit 13 supplies a continuous sheet to the sheet conveying mechanism, and includes a pair of left and right tractors 30 as shown in FIG.
As shown in FIG. 2, each tractor 30 includes a tractor drive pulley 30a, a tractor driven pulley 30b, and a tractor belt 31 wound around these pulleys 30a and 30b, and a tractor drive pulley by a drive mechanism (not shown). 30a is rotated and the tractor belt 31 is driven to convey the continuous sheet.

  In the recording operation by the recording head 20, recording for one line is performed by ejecting a recording wire from the recording head 20 while the recording head 20 is moved in the main scanning direction by the carriage 21, and recording for this one line is performed. Each time, the conveyance roller 23 (and the tractor unit 13) as the sheet conveyance mechanism unit conveys the continuous sheet for a predetermined length, and these operations are repeated.

Next, the ribbon drive mechanism of the ink ribbon cartridge 29 will be described.
FIG. 6 shows the configuration of the ribbon take-up portion of the ribbon drive mechanism. The ribbon drive mechanism is a mechanism that winds up the ink ribbon of the ink ribbon cartridge 29, and uses the power when the carriage 21 reciprocates, and uses a planetary gear mechanism or the like to perform ink in both directions of movement of the carriage 21. Take up the ribbon. FIG. 6 shows the configuration of the ribbon take-up portion, in which the male screw portion of the ribbon take-up shaft 47 attached to the back frame 27 is fitted to the female screw portion of the ribbon take-up roller 45 provided in the ink ribbon cartridge 29. The ribbon take-up shaft 47 is driven by the ribbon drive mechanism, and the ink ribbon is taken up by the ribbon take-up roller 45.

  FIG. 7A shows a state where the ribbon take-up roller 45 and the ribbon take-up shaft 47 are fitted, and FIG. 7B shows a state before the fitting.

As shown in FIG. 7B, a male threaded portion 47A is provided at the tip of the ribbon take-up shaft 47, and the male threaded portion 47A is an internal threaded portion of the ribbon take-up roller 45 of the ink ribbon cartridge 29 as shown in FIG. 7A. (Not shown in FIG. 7A). In FIG. 7B, 47B is a guide taper for the female thread portion.
8 is a cross-sectional view taken along the line XIII-XIII in FIG. 7A.
The male threaded portion 47A of the ribbon take-up shaft 47 has six teeth 147, and the female threaded portion 45A of the ribbon take-up roller 45 to which the male threaded portion 47A is fitted corresponds to the same number of the six teeth 147. Teeth 145 are formed. And in the thickness of the meshing part of each tooth 145,147, thickness T1 of the tooth 145 of 45 A of internal thread parts is formed thinner than thickness T2 of the tooth 147 of 47 A of external thread parts.

  By the way, an excessive load that pushes the ribbon take-up roller 45 may act on the ribbon take-up shaft 47 due to occurrence of a so-called ribbon lock.

In the present embodiment, when an excessive load pushing the ribbon take-up roller 45 is applied to the ribbon take-up shaft 47, the thickness T1 of the tooth 145 of the female screw portion 45A is larger than the thickness T2 of the tooth 147 of the male screw portion 47A. Since it is thin, the weak tooth 145 on the female thread 45A side of the ribbon take-up roller 45 provided in the ink ribbon cartridge 29 is lost, and power transmission between the ribbon take-up shaft 47 and the ribbon take-up roller 45 is interrupted. Be drunk.
Therefore, the ribbon lock is released and the recording wire provided in the recording head 20 can be prevented from being lost. Further, since the loss of the teeth 147 on the ribbon take-up shaft 47 side when the ribbon is locked can be prevented, the printer main body is not repaired and can be dealt with only by replacing the ink ribbon cartridge 29. Further, the conventional connecting portion is not necessary, the number of parts is reduced, and the mounting work of the cartridge 29 is facilitated.

  In the above configuration, the thickness of the tooth 145 of the female screw portion 45A is made thinner than the thickness T2 of the tooth 147 of the male screw portion 47A, thereby reducing the rigidity of the female screw portion 45A. The rigidity of the part 45A may be weakened, or the shape of the tooth 145 may be changed to weaken the rigidity of the female screw part 45A.

Next, a structure for preventing the ink ribbon cartridge 29 from falling off will be described.
In general, when the ink ribbon cartridge 29 is mounted on the left and right side frames 25 and 26 (supporting portions), the ribbon take-up roller 45 is fitted to the ribbon take-up shaft 47, and as shown in FIG. The spring portions 129 at both end portions of the ink ribbon cartridge 29 are locked to the pin members 126 provided on the inner surfaces of 25 and 26 with a weak spring force. The reason why the locking force is a weak spring force is that the ease of attaching and detaching the ink ribbon cartridge 29 is taken into consideration.

  In the present embodiment, as shown in FIG. 5, a pair of engagement pieces 61, 61 are provided at both ends of the surface of the ink ribbon cartridge 29 so as to be slidable on the surface. As shown in FIG. 9, the engagement piece 61 includes a slide portion 62 and a knob portion 63 that rises perpendicularly to the slide portion 62, and is attached to and extends from the slide portion 62 and the knob portion 63. A spring portion 65 at one end of the body 64 is provided on the surface of the ink ribbon cartridge 29 and is locked to a base portion of a stopper 66 that rises in parallel with the knob portion 63. The pair of engagement pieces 61 are biased by the spring portion 65, and the front ends 61 a of the engagement pieces 61 protrude outward from the side edges 29 a of the ink ribbon cartridge 29 and are provided on the left and right side frames 25 and 26. Locked in the locking holes 25a and 26a (supporting portions).

In a state before the ink ribbon cartridge 29 is mounted, the engaging piece 61 is biased by the spring force of the spring portion 65, and the tip 61 a of the engaging piece 61 is outward from the side edge 29 a of the ink ribbon cartridge 29. It protrudes.
When the ink ribbon cartridge 29 is mounted, the knob portion 63 and the stopper 66 are pinched to apply a knob force in the direction indicated by the arrow X, and the tip 61 a of the engagement piece 61 is resisted against the spring force of the spring portion 65. Shrink inward from the side edge 29a. This operation is performed by the user with both hands referring to FIG. Then, after the ink ribbon cartridge 29 is mounted at a predetermined mounting position, when both hands are released, the tip of the engagement piece 61 protrudes outward from the side edge 29a by the spring force of the spring portion 65 of the engagement piece 61. As above-mentioned, it latches to the locking holes 25a and 26a provided in the left and right side frames 25 and 26.

In the present embodiment, when the ink ribbon cartridge 29 is mounted, the engagement piece 61 is slid and the tip of the engagement piece 61 is locked to the locking holes 25a and 26a (supporting portions) of the left and right side frames 25 and 26. Therefore, even if an excessive load that pushes the ribbon take-up roller 45 acts on the ribbon take-up shaft 47, the ink ribbon cartridge 29 is prevented from falling off the left and right side frames 25 and 26.
Further, as described above, even in the process in which the weakened tooth 145 on the female thread portion 45A side of the ribbon take-up roller 45 is lost, an excessive load that pushes the ribbon take-up roller 45 may act on the ribbon take-up shaft 47. is there.
Also in this case, since the tip of the engagement piece 61 is locked to the left and right side frames 25 and 26, the ink ribbon cartridge 29 is prevented from falling off, and thus each device of the dot impact printer can be prevented from being damaged.

  The above-described embodiment is merely one aspect of the present invention, and can be arbitrarily modified within the scope of the present invention. For example, the engaging piece 61 is locked in the locking holes 25a and 26a of the left and right side frames 25 and 26. However, it is needless to say that the engaging piece 61 may be locked to another frame. Further, although the stationery type ink ribbon cartridge 29 has been described, the present invention is not limited to this, and each of the above embodiments can also be applied to an on-carriage type ink ribbon cartridge.

1 is a perspective view showing a dot impact printer to which an embodiment of a recording apparatus according to the present invention is applied. FIG. 2 is a side view illustrating a recording head, a carriage, and the like in FIG. 1. It is the perspective view which removed and looked at the ink ribbon cartridge. It is a perspective view which shows the frame structure of FIG. 3 seeing from the tractor unit side. FIG. 4 is a perspective view showing a state where an ink ribbon cartridge is mounted on the frame configuration of FIG. 3. It is sectional drawing which shows a ribbon drive mechanism. A and B are side views each showing a ribbon winding mechanism. It is XIII-XIII sectional drawing of FIG. 7A. It is sectional drawing which shows the engagement piece of an ink ribbon cartridge.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Printer (recording device), 20 ... Recording head, 21 ... Carriage, 25, 26 ... Side frame, 29 ... Ink ribbon cartridge, 45 ... Ribbon take-up roller, 45A ... Female thread part, 145 ... Teeth, 47 ... Ribbon winding Take-up shaft, 47A ... male screw part, 147 ... tooth, 61 ... engagement piece, 62 ... slide part, 63 ... knob part, 65 ... spring part.

Claims (6)

In a recording apparatus that includes a plurality of recording wires in a recording head mounted on a carriage and records an image on a recording medium via an ink ribbon from an ink ribbon cartridge by a protruding operation of these recording wires.
The ribbon thread take-up roller can be wound around the internal thread part of the ribbon take-up roller provided in the ink ribbon cartridge, and the ribbon take-up shaft can be driven to wind the ink ribbon. And a rigidity of the female screw portion is made weaker than that of the male screw portion, and the female screw portion is formed so as to be capable of being broken when an excessive load is applied.   The recording apparatus according to claim 1, wherein the teeth of the female screw portion are formed thinner than the thickness of the teeth of the male screw portion so as to be deficient with an excessive load.   The recording apparatus according to claim 2, wherein the tooth thickness of the female screw portion and the male screw portion is a tooth thickness of a meshing portion.   The ink ribbon cartridge includes an engagement piece that slides toward the support portion of the ink ribbon cartridge and can be engaged with the support portion to prevent the ink ribbon cartridge from falling off the mounting portion. The recording apparatus according to any one of claims 1 to 3.   The engaging piece of the ink ribbon cartridge is spring-biased so that the tip of the engaging piece protrudes outward from the side edge of the ink ribbon cartridge, and when attached, the tip of the engaging piece resists the spring force. After the mounting, the tip of the engaging piece protrudes outward from the side edge and engages with the support portion of the ink ribbon cartridge. The recording apparatus according to claim 4, characterized in that:   The recording apparatus according to claim 4, wherein the support portion is a locking hole formed in a side frame.

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