JP2001038980A - Thermal transfer printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure high quality printing by providing a head fixing base bonded with a thermal head for a platen roller in a cassette fixing section while positioning the free end side at the inlet of a fixing section, and providing a cover member at the inlet thereby regulating movement of a roll sheet in the carrying direction at the time of printing. SOLUTION: An inlet part 2a of a cassette fixing section 2 is punched in the side plate 1a of a frame 1 and one side of the fixing section 2 is opened. A thermal head 8 is bonded to a head fixing base 9 fixed to a side plate 1b on the side opposite to the side plate 1a and facing a platen roller 4. The fixing base 9 is cantilevered by the side plate 1b and placed in the fixing section 2 formed to contain a ribbon cassette. Furthermore, a cover member 24 is fixed to the side plate 1a to be opened/closed freely by means of screws and a regulating wall 25 for clamping the opposite end faces 9a, 9b at the free end 9a, when the cover member 24 closes the inlet part 2a, is formed at a part 24a for regulating movement of the free end 9a of the fixing base 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal transfer printer, and more particularly, to a thermal transfer printer in which a thermal head is mounted on a cantilevered head mounting base.

[0002]

2. Description of the Related Art A conventional thermal transfer printer is disclosed in
No. 3,149,952 is disclosed. Such a conventional thermal transfer printer has a thick plate-shaped printer base 3 on one side as shown in FIG.
The printer base 31 is provided with a paper feed unit 32 at the right end in the figure. In addition, at a position facing the paper feeding unit 32, a cassette mounting unit 33 is mounted on one side surface of the printer base 31 in a cantilever manner on the upper side.

[0003] A head operation plate 34 is mounted on the cassette mounting portion 33, one side of which is supported by the cassette mounting portion 33 and the other side is rotatable. Further, a thermal head 35 which is elastically urged by the head operation plate 34 and can move up and down is attached to the lower side of the head operation plate 34. Further, a platen roller 37a is provided below the cassette mounting portion 33 facing the thermal head 35,
The platen roller 37a is rotatably mounted on a platen support 37 that is cantilevered by the printer base 31.

The cassette mounting section 33 has an operation arm 36 attached to its free end, and the operation arm 36 can be manually rotated in the directions of arrows A and B. The other side of the head operation plate 34 is turned up and down by turning operation of the operation arm 36 in the directions of the arrows A and B, so that the thermal head 35 can be moved up and down. The rotating operation of the operation arm 36 causes the thermal head 35 to move up and down so as to be able to contact and separate from the platen roller 37a.

A case 37b for accommodating a drive source (not shown) for driving a platen roller 37a and the like is formed in the lower platen support portion 37 facing the cassette mounting portion 33. In the vicinity of the platen roller 37a on the free end side of the platen support portion 37, a support portion 37c for supporting the end portion 36a when the operation arm 36 is rotated in the direction of arrow B is formed. Then, by rotating the operation arm 36 in the direction of arrow B, the operation arm 36 is rotated.
The thermal head 35 is pressed against the platen roller 37a by a pressing portion (not shown) formed on the thermal head 35 being moved downward. The paper feed unit 32
Is formed with a roll paper supply shaft 32a, and a roll paper 39 wound in a roll shape around the roll paper supply shaft 32a is detachable.

[0006] A ribbon cassette 40 detachable from the cassette mounting section 33 is provided with a supply shaft 40 disposed on the right side in the figure.
a and the ink ribbon 40 wound around the winding shaft 40b
c is arranged around the outer circumference of the ribbon cassette 40. In the ribbon cassette 40, a gap 40e is formed between the upper ribbon guide 40d and the lower ink ribbon 40c, and the gap 40e is positioned at the free end of the cantilevered cassette mounting section 33. Thus, it is inserted into the cassette mounting section 33 and mounted. A guide plate 41 is provided between the paper feed unit 32 and the cassette mounting unit 33 near the paper feed unit 32, and the guide plate 41 is used to feed the roll paper 39 fed from the paper feed unit 32. It is designed to guide to the platen roller 37a side

In the conventional thermal transfer printer having such a configuration, the ribbon cassette 40 is mounted on the cassette mounting section 33, and the ink ribbon 40c and the roll paper 39 are held between the thermal head 35 and the platen roller 37a. The operation arm 36 is rotated in the direction of arrow B by manual operation, and a pressing portion (not shown) provided on a part of the operation arm 36
Presses the head operation plate 34 to move it downward. The downward movement of the head operation plate 34 causes the head operation plate 34
The thermal head 35 elastically urged moves toward the platen roller 37a.

Then, the thermal head 35 is connected to the platen roller 37a via the ink ribbon 40c and the roll paper 39.
Is pressed against. At this time, as shown in FIG. 15, the end portion 36a of the operation arm 36 is connected to the engaging portion 3 of the platen support portion 37.
7c, the pressure contact state between the thermal head 35 and the platen roller 37 can be maintained. Further, by manually returning the operation arm 36 to the initial state in the direction of the arrow A, the pressure contact state between the thermal head 35 and the platen roller 37 can be released.

In such a thermal transfer printer, with the ink ribbon 40c and the roll paper 39 pressed and held between the thermal head 35 and the platen roller 37a, the roll paper 39 is moved in the transport direction by the rotation of the platen roller 37a. An image of a desired color can be printed on the roll paper 39 while being transported from the upstream side to the downstream side. During this printing, the thermal head 35 moves the ink ribbon 40 c and the roll paper 39.
, The rotational force of the platen roller 37 a is applied to the thermal head 35, and the platen roller 37 a
A force is applied to move in the same direction as the rotation direction.

[0010]

However, since the cassette mounting portion 33 is cantilevered by the printer base 31, the rotational force of the platen roller 37a applied to the thermal head 35 during printing causes the cassette mounting portion 33 to rotate. The free end side sometimes moved in the transport direction of the roll paper 39. When the cassette mounting portion 33 moves during such printing, the thermal head 35 cannot be uniformly pressed against the platen roller 37a. For this reason, there is a problem in that print unevenness or the like occurs in an image printed on the roll paper 39, and print quality deteriorates.

The thermal transfer printer of the present invention has been made in view of the above-described problems, and restricts the movement of the roll paper, which is applied to the cantilevered thermal head in the transport direction during printing, in the transport direction to achieve high quality. It is an object of the present invention to provide a thermal transfer printer capable of printing an image.

[0012]

According to a first aspect of the present invention, there is provided a thermal transfer printer having a ribbon cassette containing an ink ribbon, and a cassette mounting portion to which the ribbon cassette can be attached and detached. A frame, a rotatable platen roller, and a head mount that is cantilevered on a side plate of the frame and has a thermal head fixed to a position facing the platen roller. It is formed in the cassette mounting portion formed so as to extend in parallel with the center of rotation and configured to accommodate the ribbon cassette, and has a free end located at an entrance side of the cassette mounting portion, and the entrance portion is A lid member capable of closing the entrance was provided on the formed side plate side.

[0013] As a second means for solving the above-mentioned problems, the lid member is attached to the side plate on which the entrance is formed so as to be openable and closable, and the lid is closed with the entrance closed. It has a configuration having a restricting portion that can restrict the movement of the head mount.

According to a third aspect of the present invention, when the lid member closes the entrance portion, the regulating portion is configured to move the head mounting base in the width direction on the free end side. A pair of regulating walls capable of sandwiching both end faces are formed, and the movement of the head mount in the conveying direction of the recording sheet when printing an image on the recording sheet is regulated by the regulating section.

According to a fourth aspect of the present invention, when the cover member closes the entrance, the cover member is connected to the frame. The locking means for stopping is provided.

According to a fifth aspect of the present invention, the locking means includes a positioning pin protruding from a side plate having the entrance and a positioning pin formed on the lid member. A positioning hole that can be fitted, such that when the lid member closes the entrance, the positioning hole fits into the positioning pin, and the lid member is locked to the frame. The configuration was adopted.

As a sixth solution for solving the above-mentioned problem, the locking means is formed on an engagement recess formed in the frame and the lid member engageable with the engagement recess. An engagement projection, wherein when the lid member closes the entrance, the engagement projection engages with the engagement recess, and the lid member is locked to the frame. Configuration.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A thermal transfer printer according to the present invention will be described below with reference to FIGS. 1 is a front view of a first embodiment of the thermal transfer printer of the present invention, FIG. 2 is a bottom view of FIG. 1, FIG. 3 is a left side view of FIG. 1, and FIG. 5 is a top view when the lid member according to the present invention is closed, FIG. 6 is a front view of FIG. 5, and FIG. 7 is a schematic perspective view around a platen roller according to the present invention. 8 is a schematic diagram for explaining the operation of the platen roller according to the present invention, FIG. 9 is a top view of the ribbon cassette according to the present invention, and FIG. 10 is a right side view of FIG. FIG. 11 is a front view of FIG. 9, and FIG. 12 is a sectional view of a main part for explaining the operation of the thermal transfer printer of the present invention.

The thermal transfer printer of the present invention is provided with a frame 1 made of a metal plate and having a box-like outer shape, and the frame 1 is formed with a hollow inside. The frame 1 is formed by bending by pressing or the like.
As shown in FIG. 3, a side plate 1a formed on the near side and a side plate 1b formed on the rear side at a position facing the side plate 1a.
And a top plate 1c that covers the upper part inside the cavity, and a lower plate 1d that covers a part of the lower part inside the cavity on the left side in the figure. A cassette mounting portion 2 is formed inside such a cavity of the frame 1, and an opening 2a of the cassette mounting portion 2 as shown in FIG. 1 is punched and formed in the side plate 1a. One side of the part 2 is formed open. Such a cassette mounting section 2
Is configured such that a ribbon cassette 17 described later can be detached from the entrance 2a.

The cassette mounting portion 2 has a rotatable take-up bobbin 3 disposed on a side plate 1b opposite to the side plate 1a having an entrance 2a formed therein. Take-up roller 2 for cassette 17
0 is located and can be engaged. A hole 1e for positioning a ribbon cassette 17 to be described later is punched and formed in the side plate 1b near the winding bobbin 3. Also, as shown in FIGS. 3 and 4, the end face 1f of the top plate 1c on the side plate 1a side is slightly bent outward, so that the cassette mounting portion 2 of the ribbon cassette 17 described later is used.
Easy to put on and take off.

As shown in FIG. 2, the frame 1 is provided with a rotatable platen roller 4 supported by both side plates 1a and 1b via a support member 5. The platen roller 4 has a configuration in which a rotary shaft 4a is covered with a rubber roller 4b. The platen roller 4 is
Both ends of the rotating shaft 4a are supported by a pair of supporting members 5, respectively, and are rotatable. The pair of support members 5
Is formed of a metal plate, and an end portion side of the platen roller 4 opposite to the side supporting the rotation shaft 4a is bent into a substantially right-angled L-shape to form a bent portion 5a. Such a pair of support members 5 are provided on both side surfaces 1 of the frame 1.
The shaft member 6 is rotatably mounted near an end of a shaft member 6 rotatably supported by the members a and b. The bent portions 5a face inward so as to face each other.

The shaft member 6 has a pair of first and second pins 6a and 6b, which protrude in the same direction and are fixed to the outer peripheral surface, inside the support member 5 pivotally supported near the ends. It is arranged on the side close to the support member 5. The bent portion 5a of the support member 5 can contact the first pins 6a, 6a near the support member 5. The shaft member sandwiched between the first and second pins 6a and 6b has springs 6 respectively.
c, 6c are wound, one end of the spring 6c abuts the bent portion 5a of the support member 5, and the other end of the spring 6c is the second pin 6b.
Assembled in contact with

The support member 5 and the shaft member 6 are urged to rotate clockwise in FIG. 7 by the spring force of the spring 6c, and the support member 5 is rotated counterclockwise. , So that the bent portion 5
a and the first pin 6a are always in contact with each other. Therefore, the platen roller 4 is
When the shaft member 6 shown in FIG. 8 rotates counterclockwise, the platen roller 4 rotates in the direction of arrow C, and the shaft member 6 shown in FIG.
When the shaft member 6 rotates clockwise, the platen roller 4 rotates in the direction of arrow D. That is, the platen roller 4 is supported by both side plates 1a and 1b of the frame 1 so as to be rotatable in the directions of arrows C and D.

The shaft member 6 shown in FIG.
A cam lever 7 is secured to one end of the lower end of the side plate 1b which projects outward from the lower side plate 1b. This cam lever 7
Is formed of a resin material. As shown in FIG. 8, a lever portion 7a is formed so that a part of the outer peripheral portion protrudes downward in the figure, and a position detecting portion 7b is formed to protrude from a part of the lever portion 7a. 7 is formed in a forked shape.

A thermal head 8 is disposed at a position facing the platen roller 4, and a head mount 9 to which the thermal head 8 is fixed with an adhesive or the like is fixed to one side plate 1b of the frame 1 by screws or the like. It is supported and mounted. The head mounting base 9 is made of a material having good heat dissipation such as aluminum die casting, is cantilevered by the side plate 1b, and is located in the cassette mounting portion 2 formed so as to house a ribbon cassette 17 to be described later. The free end 9a side projects slightly outward from the entrance 2a of the cassette mounting portion 2.

The cassette mounting portion 2 between the top plate 1c of the frame 1 and the head mounting base 9 has a gap 2c of a predetermined size.
Is formed, and a ribbon guide portion 17b of the ribbon cassette 17 described later can be inserted into the gap portion 2c.
A torsion coil spring 10 is wound around the shaft member 6 between the side plate 1b and a cam lever 7 attached to one end of the shaft member 6 that protrudes outward from the side plate 1b. This torsion coil spring 10 has one end locked to the cam lever 7 and the other end locked to the frame 1 side, and constantly biases the shaft member 6 shown in FIG. 8 in a counterclockwise direction. 4 is always urged to rotate away from the thermal head 8 in the direction of arrow D.

A cam member 11 is provided at a position facing the lever portion 7a of the cam lever 7, and the cam lever 7 and the cam member 11 constitute a cam mechanism. The cam member 11 is made of a resin material, and as shown in FIG. 6, is formed by combining outer radii of different radii, that is, a large radii and a small radii, and is formed in a fan shape. , Can be rotated by rotation of a drive source (not shown).

When the cam member 11 is rotated to bring the outer peripheral portion having a large radius into contact with the lever portion 7a, the shaft member 6 rotates forward in the clockwise direction and resists the spring force of the torsion coil spring 10. The platen roller 4 can be rotated in the direction of arrow C toward the thermal head 8. Further, when the cam member 11 is further rotated to bring the outer peripheral portion having a small radius into contact with the lever portion 7a, the shaft member 6 is rotated in reverse by the spring force of the torsion coil spring 10, and the platen roller 4 is moved in the direction of arrow D. By rotating, the platen roller 4 is separated from the thermal head 8.

Further, in the thermal transfer printer of the present invention, a wall member 12 made of a resin material is disposed inside the cavity on the left end side of the frame 1 shown in FIG. As shown, the sheet insertion opening 12a leading to the internal cassette mounting section 2 is formed open. FIG.
The right side of the platen roller 4 shown in FIG.
A paper feed roller 13 made of a metal bar or the like is disposed downstream of the thermal head 8 in the transport direction 3. The paper feed roller 13 and a pressure roller 14 that presses against the paper feed roller 13 are rotatably mounted on a resin bearing 1g mounted on both side plates 1a and 1b.

As shown in FIG. 2, the paper feed roller 13 has a rotating shaft 13a projecting downward and outward from the side plate 1b.
A helical gear 15 having teeth formed at an angle is attached thereto, and the rotation of a drive source (not shown) is transmitted to the paper feed roller 13 via the helical gear 15, and the paper feed roller A pressing roller 14 that presses against the roller 13 is rotatable in a direction opposite to the rotation of the paper feed roller 13. Outside the side plate 1b, on the side where the helical field gear 15 is disposed, not only the helical gear 15 but also a plurality of drive members for transmitting driving force to various driving members such as the platen roller 4. A drive source such as a gear or a motor is attached.
Illustration and description are omitted. The pressing roller 14
A substantially V-shaped leaf spring 16 as shown in FIG. 1 is disposed between the leaf spring 16 and the top plate 1 c of the frame 1.
Thus, the pressure roller 14 is always in pressure contact with the paper feed roller 13.

The ribbon cassette 17 detachable from the cassette mounting section 2 will be described with reference to FIGS.
As shown in FIG. 11, the ribbon cassette 17 includes a main body 17a formed substantially in an elliptical shape, and a ribbon guide 17b which is a part of the main body 17a extending to one side from the main body 17a. It is configured. An ink ribbon 18 is housed inside the main body 17a, and the ink ribbon 18 is wound around a supply roller 19 and a take-up roller 20 whose both ends are housed in the main body 17a. Further, the ribbon cassette 17 is formed with a ribbon folding portion 17d in which a rotatable roller 17c is attached to the tip of a ribbon guide portion 17b.

Also, the main body 17a and the ribbon folded portion 1
As shown in FIG. 10, a ribbon guide groove 17g having a predetermined gap size is formed in the ribbon guide portion 17b between the upper plate 17e and the lower plate 17f. The ink ribbon 18 can run in the groove 17g. The ink ribbon 18 is rotated by the take-up roller 20 shown in FIG.
Once drawn out from the supply roller 19 inside, it is drawn around in the direction of arrow F, and is folded upward by the ribbon folding section 17d. Then, the ink ribbon 18 can be drawn back into the main body portion 17a through the ribbon running groove 17g of the ribbon guide portion 17b from the state of being folded back at the ribbon folding portion 17d, and can be wound around the winding roller 20. It has become.

As shown in FIG. 11, the main body 17a
Between the ribbon guide portion 17d and the ribbon return portion 17d.
A head insertion portion 21 into which the head mounting base 9 can be inserted is formed on the lower surface side of b. In the vicinity of the take-up roller 20 slightly protruding above the ribbon cassette 17 shown in FIG. 9, a projection 17h that can be fitted to the hole 1e of the side plate 1b when mounted on the cassette mounting portion 2 is formed so as to protrude. .
When the ribbon cassette 17 is mounted on the cassette mounting section 2, the head mount 9 is inserted into the head insertion section 21, the projection 17h is fitted into the hole 1e of the side plate 1b, and the ribbon cassette 17 is mounted on the cassette mounting section 2. Positioned. Further, a drawer 17j extending in a tongue shape from the lower end face of the main body 17a shown in FIG.

In the frame 1, a cover member 24 capable of closing the entrance 2a as shown in FIG. 1 is provided on the side plate 1a side where the entrance 2a is formed. This lid member 24
Is made of a metal plate such as stainless steel, and is disposed below the side plate 1a in which the entrance 2a is formed, as shown in FIG. As shown in FIG. 2, the left and right ends of the lid member 24 are attached to the side plate 1 a so as to be openable and closable with screws 26 and the like. Is formed by stamping. The regulating member 24a has an opening 2a
When the cover is closed, a pair of regulating walls 25 are formed which can hold both end surfaces 9b, 9b in the width direction on the free end 9a side of the head mounting base 9. The restricting wall 25 is a restricting portion 2 shown in FIG.
The side wall 4a in the width direction is cut and raised to face each other.

The pair of opposing regulating walls 25 are
As shown in FIG. 5, the cut and raised root portion can hold both end surfaces in the width direction on the free end 9 a side of the head mount 9. The cut and raised tip portion is bent outward. Therefore, the lid member 2
When the door 4 closes the entrance portion 2a, the regulating wall 25 of the regulating portion 24a is smoothly guided to the free end 9a side of the head mounting base 9, and the free end 9a side of the head mounting base 9 is narrowed by the regulating wall 25. You can have. Further, the lid member 24 is provided with a stopper portion 24b formed by bending the upper end portions on both right and left sides shown in FIG.

The lid member 24 and the frame 1 are provided with locking means for locking the lid member 24 to the frame 1 when the lid member 24 closes the entrance 2a. Means include a positioning pin 27 attached by caulking or the like to the upper right side of the side plate 1a in which the entrance 2a is formed as shown in FIG. 1, and a positioning pin formed to penetrate the upper side of the lid member 24 to the upper right side as shown in FIG. The positioning pin 27 can be fitted into the positioning hole 24c. When the lid member 24 closes the entrance 2a, the positioning holes 24c are fitted into the positioning pins 27 to lock the lid member 24 to the frame 1 and restrict the movement of the lid member 24 relative to the frame 1. It is supposed to.

A sheet guide 22 made of a metal plate is provided below the inclined portion 2b of the cassette mounting portion 2 shown in FIG. As shown in FIG. 2, a plurality of rib grooves 22a are formed in the paper guide 22, so as to reduce the frictional resistance with the recording paper 23 shown in FIG.
The recording paper 23 can be used in either a roll shape or a cut paper shape, and is fed from a feeding unit (not shown).

As shown in FIG. 12, the recording paper 23 supplied from the paper supply unit (not shown) is inserted into the paper insertion port 12 with the ribbon cassette 17 mounted on the cassette mounting unit 2.
a can be inserted. The recording paper 23 inserted from the paper transport port 12a passes through a lower portion of the ribbon cassette 17 mounted on the cassette mounting unit 2, and is transported between the thermal head 8 and the ink ribbon 18 via the paper guide 22. Is pressed and held between the paper feed roller 13 and the pressure roller 14. The paper feed roller 23 and the pressing roller 1
The recording paper 23 pressed and held in contact with the paper feed roller 1
By the rotation of 3, the recording paper 23 can be transported from the upstream side to the downstream side in the transport direction P.

The printing operation of the thermal transfer printer of the present invention having such a configuration will be described. First, a driving source (not shown) is driven to drive a cam member composed of the cam lever 7 and the cam member 11 as shown in FIG. By rotating the platen roller 4 in the direction of arrow D, the platen roller 4 is separated from the thermal head 8. Next, the head insertion section 21 of the ribbon cassette 17 is positioned at the free end 9a of the head mount 9, and the ribbon cassette 17 is inserted into the cassette mounting section 2 from the entrance 2a and mounted. Then, the head mount 9 is located at the head insertion portion 21 of the ribbon cassette 17, and the ink ribbon 18 pulled out from the main body portion 17 a toward the ribbon folding portion 17 d is located between the thermal head 8 and the platen roller 4. . Also, the ribbon guide 17b
Are located in the gap 2c between the head mount 9 and the top plate 1c of the frame 1.

When the ribbon cassette 17 is mounted on the cassette mounting portion 2, the projection 17h fits into the hole 1e of the side plate 1b and the winding roller 20 is mounted on the winding bobbin 3.
Engage. Then, in conjunction with the rotation of the winding bobbin 3, the winding roller 20 becomes rotatable in the direction of arrow E. At this time, the tongue-shaped drawer 17j is connected to the entrance 2
The state protrudes outside from a.

Next, as shown in FIG.
Is inserted from the paper insertion slot 12a, and the recording paper 23
And the leading end of the recording paper 23 is pressed and held between the paper feed roller 13 and the pressing roller 14. Next, when the lid member 24 is operated and the lid member 24 closes the entrance 2a, both end surfaces in the width direction on the free end 9a side of the head mount 9 are narrowed by the pair of regulating walls 25 of the regulating portion 24a. Be held. At this time, the lid member 24 is locked to the frame 1 with the positioning pin 27 fitted in the positioning hole 24c and the entrance 2a closed. The closing of the entrance 2a by the lid member 24 may be performed before the recording paper 23 is conveyed to the paper feed roller 13 side.

Next, the ink ribbon 18 and the recording paper 23 are moved between the thermal head 8 and the platen roller 4 by rotating the platen roller 4 in the direction of arrow C by the cam mechanism including the cam lever 7 and the cam member 11. Pressing and holding. When the platen roller 4 is in pressure contact with the thermal head 8, a dot-like heat generating portion (not shown) of the thermal head 8 intermittently generates heat based on recording information, and performs recording by rotation of the paper feed roller 20. By transporting the paper 23 downstream, the ink of the ink ribbon 18 is transferred to the recording paper 23, and a desired image can be printed on the recording paper 23.

In such a thermal transfer printer according to the present invention, the rotatable platen roller 4 is in pressure contact with the thermal head 8 via the ink ribbon 18 and the recording paper 23 while an image is being printed on the recording paper 23. For this purpose, the paper feed roller 13 transports the recording paper 23 downstream in the transport direction P and winds the ink ribbon 18 so that the free end 9 a of the head mounting base 9 is moved in the transport direction of the recording paper 23. The force to move is added.

Even if such a force as to move the free end 9a side of the head mount 9 is applied during printing, the thermal transfer printer of the present invention can maintain the free end 9a of the head mount 9.
The side is sandwiched by a pair of regulating walls 25 formed on the regulating portion 24a of the lid member 24 to restrict the movement.
The positioning pin 27 and the positioning hole 24 serving as locking means
With c, the movement with respect to the frame 1 is regulated, and the movement of the head mount 9 on the free end 9a side during printing can be reliably regulated.

As another embodiment of the present invention,
The locking means for locking the lid member 24 in a state in which the entrance 2a is closed is not shown, but is engageable with an engaging recess formed in the frame 1 and the engaging recess. When the cover 24 closes the entrance 2a, the engaging protrusion engages with the engaging recess, and the cover 24 is attached to the frame 1. It may be one that is locked.

[0046]

As described above, in the thermal transfer printer of the present invention, the lid member capable of closing the entrance is provided on the side plate side where the entrance of the cassette mounting portion is formed. The movement of the head mount can be regulated by the lid member, and a thermal transfer printer capable of printing high-quality images can be provided. In addition, since the entrance is closed by the lid member during printing, the operator cannot erroneously remove the ribbon cassette during printing.

Further, the cover member has a restricting portion that can restrict the movement of the head mounting table in a state where the entrance is closed, and the head is mounted in the transport direction of the recording paper when printing an image on the recording paper. Since the movement of the table is regulated by the regulation section, the movement of the free end side of the head mounting table during printing can be reliably regulated, and a thermal transfer printer capable of printing high-quality images can be provided.

The restricting portion has a pair of restricting walls which can hold both end surfaces in the width direction on the free end side of the head mount when the lid member closes the entrance portion. Since the movement of the head mount in the transport direction of the recording paper during printing is restricted by the restricting portion, the movement of the free end of the head mount during printing can be reliably performed by the restricting wall. Can be regulated.

Further, the lid member and the frame are provided with locking means for locking the lid member to the frame when the lid member closes the entrance, so that the entrance is closed. Can be securely locked by the locking means,
The lid member does not open due to vibration or the like.

The locking means comprises a positioning pin attached to a side plate having an entrance formed therein, and a positioning hole formed in the lid member, into which the positioning pin can be fitted.
When the lid member closes the entrance, the positioning holes are fitted to the positioning pins and the lid member is locked to the frame, so that the lid member is securely locked to the frame with the lid closed. be able to.

The locking means comprises an engagement recess formed in the frame and an engagement projection integrally formed on the lid member engageable with the engagement recess. When the cover is closed, the engaging protrusion engages with the engaging recess, and the lid member is locked to the frame. Therefore, when the lid member is processed by pressing or the like, the engaging convex portion is simultaneously formed. Can be
A low-cost thermal transfer printer can be provided.

[Brief description of the drawings]

FIG. 1 is a front view of a first embodiment of a thermal transfer printer according to the present invention.

FIG. 2 is a bottom view of FIG.

FIG. 3 is a left side view of FIG.

FIG. 4 is a right side view of FIG. 1;

FIG. 5 is a top view when the lid member according to the present invention is closed.

FIG. 6 is a front view of FIG. 5;

FIG. 7 is a schematic perspective view around a platen roller according to the present invention.

FIG. 8 is a schematic diagram illustrating the operation of a platen roller according to the present invention.

FIG. 9 is a top view of the ribbon cassette according to the present invention.

FIG. 10 is a right side view of FIG.

FIG. 11 is a front view of FIG. 8;

FIG. 12 is a sectional view of a main part for explaining the operation of the thermal transfer printer of the present invention.

FIG. 13 is a perspective view of a conventional thermal transfer printer.

FIG. 14 is a perspective view illustrating the operation of a conventional thermal transfer printer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Frame 1a, 1b Side plate 1c Top plate 1f End surface 2 Cassette mounting part 2a Entrance part 2c Gap part 3 Take-up bobbin 4 Platen roller 4b Rubber roller 5 Support member 5a Bending part 6 Shaft member 6a 1st pin 6b 2nd pin 7 Cam lever 8 Thermal head 9 Head mount 9a Free end 10 Torsion coil spring 11 Cam member 13 Paper feed roller 14 Pressure contact roller 17 Ribbon cassette 17a Main body 17b Ribbon guide 17d Ribbon fold 18 Ink ribbon 19 Supply roller 20 Winding roller 21 Head Insertion part 21a Narrow part 22 Paper guide 23 Recording paper 24 Lid member 24a Restriction part 24c Positioning hole 25 Restriction wall 26 Screw 27 Positioning pin

Claims (6)

[Claims] 1. A ribbon cassette accommodating an ink ribbon, a frame having a cassette mounting portion to which the ribbon cassette can be attached and detached, a rotatable platen roller, and a cantilever supported by a side plate of the frame. A head mounting base to which a thermal head is fixed at an opposing position, wherein the head mounting base extends parallel to the rotation center of the platen roller, and is formed to accommodate the ribbon cassette. In addition to being located in the mounting portion, the free end side is located at the entrance side of the cassette mounting portion, and a lid member capable of closing the entrance portion is disposed on the side plate side where the entrance portion is formed. And thermal transfer printer. 2. The apparatus according to claim 2, wherein the lid member is provided on the side plate on which the entrance portion is formed so as to be openable and closable, and has a regulating portion capable of regulating the movement of the head mounting base with the entrance portion closed. The thermal transfer printer according to claim 1, wherein: 3. The restricting portion is formed with a pair of restricting walls capable of holding both end surfaces in the width direction on the free end side of the head mounting base when the lid member closes the entrance portion. 3. The thermal transfer printer according to claim 2, wherein the movement of the head mount in the transport direction of the recording sheet when printing an image on the recording sheet is restricted by the restricting portion. 4. The apparatus according to claim 1, wherein said lid member and said frame are provided with locking means for locking said lid member to said frame when said lid member closes said entrance. The thermal transfer printer according to claim 1, 2 or 3, wherein: 5. The locking means comprises: a positioning pin attached to a side plate having the entrance formed therein; and a positioning hole formed in the lid member to which the positioning pin can be fitted. 5. The thermal transfer printer according to claim 4, wherein when the lid is closed, the positioning hole is fitted to the positioning pin, and the lid member is locked to the frame. 6. The locking means comprises an engaging recess formed in the frame and an engaging protrusion integrally formed on the lid member engageable with the engaging recess. 5. The thermal transfer device according to claim 4, wherein when the cover is closed, the engaging protrusion engages with the engaging recess so that the cover is locked to the frame. Printer.