JPS6025778A - Antistatic structure of ribbon cassette - Google Patents

Abstract

PURPOSE:To prevent erroneous printing operation caused by static electricity in a ribbon cassette, by forming a conductive layer to the inner surface of the ribbon cassette so as to expose a part of said layer to the outer surface thereof, and bringing the exposed part into contact with the conductive member provided to the main body side of a printing apparatus. CONSTITUTION:In a ribbon cassette 6 used by attaching the same to the main body of a printing apparatus, a conductive layer 26 is formed to the inner peripheral surface of the cassette case 16 while a part 30 of the conductive layer 26 is drawn out of the outer periphery of the cassette case 16 and the conductive member 44 for use in contact provided to the main body side is brought into contact with said part 30 to earth the interior of the cassette case 16. Ribbon guides 54, 56, 64, 66 for guiding an ink ribbon 32 along the printing part surface of a platen are made of a conductive member and pref. earthed.

Description

[Detailed Description of the Invention] Attach the Nukikokuran Ribbon Force Set 1 to the main body of the printer and printer to be used.
The present invention relates to an antistatic structure for a ribbon cassette that prevents static electricity from being charged inside the ribbon cassette in a printing device such as a typewriter.

In a printing device that attaches a ribbon cassette to the main body and prints using the ribbon stored in the ribbon cassette, when the ribbon runs, the ribbon moves between the ribbon cassette, ribbon feed belt, ribbon guide, and ribbon guide. When it comes into contact with rollers, etc., static electricity is generated due to the friction between them. Further, there are disadvantages in that the ribbon is attracted to the paper, and static electricity accumulated in the ribbon force set 1 is eventually discharged, causing the printing device to malfunction.

Therefore, in conventional printing devices of this type, the feed roller (1) is made of a conductive material as shown in FIG. 1, and the feed roller (1) is connected to the feed roller as shown in FIG. Ribbon feed motor to roller (2)
The drive shaft (3), which transmits the rotation of
) is configured to release the water to the outside.

However, such a configuration is still insufficient as a countermeasure, and the above-mentioned drawbacks could not be completely eliminated.

Therefore, the present invention aims to completely eliminate the above-mentioned drawbacks by preventing static electricity from being charged in the ribbon cassette in a printing device in which the ribbon cassette is attached to the main body. With the goal.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below based on embodiments of the invention shown in the drawings.

FIG. 3 shows a state in which the ribbon cassette according to the present invention is attached to the body frame of a thermal printer as an example of a printing device. What is indicated by the symbol (io) in the figure is a ribbon cassette. The ribbon cassette is attached to the printer main body (1
2) is fixedly installed on the main frame (14) provided on both sides of the main body frame (14). As shown in FIGS. 3, 4 and 5, the cassette case (16) of this ribbon cassette (10) consists of an upper lid (18) and a lower case (20) on which it is covered.
It consists of As shown in FIG. 4, a take-up spool (22) and a feed-out spool (24) are rotatably attached to the lower case at intervals. A thin conductive sheet (26) made of, for example, polyethylene mixed with carbon is laid on the inner surface of the bottom wall (20a) of the lower case (2o). This conductive sheet has holes that match the outer diameters of the take-up spool (22) and the pay-out spool (24). Furthermore, conductive sheet 1~
(26) is a ribbon end formed near the right side wall (20b) of the lower case (20) by bending one narrow end (on the right side in the figure) as shown in FIGS. 4 and 5. It is pulled out from the detection hole (28), and its pulled-out portion (30) is aligned with the outer surface of the bottom wall (20a) of the lower case (20). A ribbon (32) is wound around the take-up spool (22) and the feed-in pool (24) on the conductive sheet (26). This ribbon is pulled out to the outside from its feed-out port (34), and then drawn into the ribbon cassette (10) again through its collection port (36). This ribbon (32)
further includes a feed roller (38) and a pinch roller (
40) and is wound around the take-up spool (22). The feed roller (38) is connected to a ribbon feed motor (not shown), and its rotation is transmitted to feed the ribbon (38) wound around the edge spool (24).
2) through the above-mentioned path to the take-up spool (22).
It is designed to be sent while being rolled up.

Here, the ribbon cassette (10) configured as described above is attached to the main body frame (14) as described above. As shown in FIG. 5, a bracket (42) made of a conductive material is attached to this main body frame, and a leaf spring (44) also made of a conductive material is attached onto the bracket 1-. Ribbon cassette (10) on this leaf spring
The drawer portion (30) of the conductive sheets 1 to (26) in
contact elastically. As a result, the conductive sheet (26
) is electrically connected to the body frame (14) via a leaf spring (44). This main body frame is grounded so that the static electricity inside the ribbon cassette (10) mentioned above is always released to the outside.

Furthermore, when this ribbon cassette (10) is installed, the portion of the ribbon (32) pulled out to the outside touches the paper (48) wrapped around the platen (46), as shown in FIGS. 3 and 6. A thermal head (52) supported by a carriage (50) faces each other, and a pair of bottle-shaped ribbon guides (54) and (56) are provided with the thermal head (52) sandwiched therebetween.
inserted between. This ribbon guide is made of a conductive material such as stainless steel, and is attached to a carriage (50), and a movable arm (58) also made of a conductive material.
(60) is erected and fixed at one end on the paper (48) side. Guide auxiliary members (62) and (64) bent into an L shape are arranged on top of the movable arms (58) and (60). This guide auxiliary member has a bent piece (
66) and (67) along the platen (46),
It is formed wide and is bent round toward the front as shown in the figure to guide the ribbon (32) so that it can be easily inserted between the thermal head (52) and the ribbon guides (54) and (56). And these movable arms (58
)・(60) and guide auxiliary members (62)・(64)
, the left and right members are screwed (68) on the outside of each other.
(6B) is mounted on the carriage (50) by the screw so that it can be opened and closed. Furthermore, here, on the carriage (50), movable arms (58) and (6
0) and guide auxiliary members (62) and (64), the conductive connection plate (70) is attached by screws (68) and (68). This conductive connection plate is connected to the carriage (50
) extends across each pair of movable arms (58), (60) and guide auxiliary members (62), (64), and is further bent downward to provide a ground line (not shown). connected to a flexible printed board. This flexible printed board has a main body frame (1
4) is connected to the fixed electronic circuit part. As a result, the static electricity charged on the ribbon (32) pulled out from the feeding opening (34) of the ribbon force separator h (10) is transferred from the ribbon guides (54) and (56) to the movable arm (58) and
(60), conductive connection plate (70), flexible printed board, and main body frame (14).

In the embodiments described above, the antistatic structure of the present invention was applied to a thermal printer, but the present invention can also be applied to various printing devices such as other printers and typewriters as long as the ribbon cassette is attached to the main body and used. can be applied to Furthermore, the ribbon cassette (10
) is fixedly installed on the main body frame (14). However, the present invention is equally applicable to a ribbon force set 1- mounted on a reciprocating carriage. Furthermore, the present invention can be applied to various ribbons such as ink ribbons and heat-sensitive ribbons as long as the ribbons include a member that can be charged with static electricity as the ribbons stored in the ribbon cassette.

Further, in the present invention, in the above-mentioned embodiments, an example was shown in which a conductive sheet (26) was laid on the lower case (20) as the conductive layer of the ribbon cassette (10). However, as this conductive layer, for example, a metal foil such as copper foil may be placed on the lower case, or conductive coating may be applied. Furthermore, the present invention is not limited to the location where the conductive layer is disposed on the inner surface of the top lid or elsewhere as long as it is inside the cassette case. Furthermore, in the above embodiment, a leaf spring (44) was used as the conductive member that comes into contact with the drawn-out portion (30) of the conductive sheet 1-(26), which is the conductive layer. but,
In the present invention, various spring members such as coil springs can be used as long as they are elastic conductive members.

Furthermore, in the embodiment described above, the ribbon guide (54)
(56), but in this invention, for example, the movable arm 4. It is also possible to make a plate-shaped guide piece stand up from (5, 8) and (60) and use it as a ribbon guide. Furthermore, in the embodiment described above, a conductive connection plate (70) is separately attached to the carriage (50), and the flexible printed board is connected to the flexible printed board through the conductive connection plate for grounding. However, it goes without saying that the ribbon guide may be directly connected to the main body frame and grounded by another conductive member, for example.

Effects According to the present invention, in a printing device in which a ribbon force set 1- is attached to the main body and used, a conductive layer is formed on the outer surface of the cassette case, and a part of the conductive layer is drawn out to the outer surface of the cassette case to actively apply it to the printing device main body. Since the configuration is such that the static electricity charged inside the ribbon cassette is constantly released, it is possible to prevent static electricity from accumulating inside the ribbon cassette and discharging it, thereby accurately preventing malfunctions of the printing device. It is possible to provide an electrostatic charge prevention structure with an extremely simple configuration that can prevent problems such as the ribbon being attracted to and sticking to the paper.

Further, according to the present invention, since the ribbon guide made of a conductive member is configured to be actively electrically connected to the main body of the printing device, the ribbon pulled out from the cassette case may be damaged as the carriage moves or the like. Even if static electricity is generated and charged due to friction with other parts such as guides, the static electricity can be released each time, thereby reliably preventing malfunctions of the printing device if the ribbon gets tied to paper, etc. be able to.

[Brief explanation of the drawing]

FIG. 1 is a plan view schematically showing the internal structure of a conventional ribbon cassette. FIG. 2 is a sectional view showing the antistatic structure of a conventional ribbon cassette. FIG. 3 is an overall perspective view showing a thermal printer as an example of a printing device equipped with the electrostatic charging prevention structure of the ribbon force set 1 of the present invention. FIG. 4 is a plan view showing the internal structure of the ribbon cassette according to the present invention with the top cover removed. FIG. 5 is a cross-sectional view showing a state in which the conductive portion of the ribbon cassette is electrically connected to the printer main body. FIG. 6 is an enlarged perspective view of the carriage of the thermal printer shown in FIG. 3, showing the antistatic structure of the ribbon cassette according to the present invention. (Work 0)... Ribbon cassette (12)...
...Printer body (I4) ...Body frame (16) ...Cassette case (2G)
...... Conductive sheet (30) ...... Pull-out part of the conductive sheet (32) ... Ribbon (44) ...... Leaf spring (50) Carriage (54) (5
G)・・・・・・Ribbon guide (70)・・・・
... Conductive connection plate patent applicant Rico Co., Ltd. Ricoh Electronics Co., Ltd. agent Patent attorney Shun Nakao Bunpei 3 Figure 2

Claims (1)

[Claims] 1. In a printing device that uses a ribbon cassette that can be inserted into the main body, a conductive layer is formed on the inner surface of the cassette case,
A ribbon force set is provided in which a part of the conductive layer is pulled out to the outer surface of the cassette case, a conductive member is provided on the printing device main body side that comes into contact with the pulled-out part when the ribbon cassette is installed, and the conductive part is grounded. 1- Anti-static structure. 2. In a printing device that uses a ribbon cassette attached to the main body, a conductive layer is formed on the inner surface of the cassette case,
A part of the conductive layer is drawn out to the outer surface of the force cell 1 case, and a conductive member is provided on the printer main body side that comes into contact with the drawn-out part when the ribbon cassette is attached, and the conductive member is grounded. A ribbon guide is provided to guide the ribbon along the paper wound around the platen, the ribbon guide is made of a conductive member, the ribbon guide is connected to a conductive connecting member, and the conductive connecting member is grounded. Anti-static structure of ribbon cassette.