JP2973241B2 - Line thermal printer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a line thermal printer which prints or prints on a dot line by using a thermal paper as a printing paper, and more particularly to a thermal head support and a head-up. Regarding the mechanism.

[0002]

2. Description of the Related Art Conventionally, in a line thermal printer, generally, a thermal paper is sandwiched between a platen and a head, the platen is rotated, and the paper is fed by the frictional force. As disclosed in Japanese Utility Model Laid-Open Publication No. 60-164, there is a head-up mechanism that lifts the head until a required space is obtained between the platen and the head by operating a lever. The purpose of this head-up mechanism is to lift the head and prevent the platen from deforming when the thermal paper is installed or the printer is not used for a long period of time. Is also 10 mm or less. Therefore, when performing maintenance such as cleaning of the head surface, the head surface is exposed by performing disassembly or deformation of the head support portion by removing screws or the like, or as disclosed in JP-A-63-134274. The head was removed.

In a line thermal printer, since the thermal paper is heated in the line direction with a dot pitch accuracy, the printing quality depends on how accurately the position of the heat generating portion of the thermal head can be determined with respect to the platen. It is an important factor that influences.

[0004]

However, in the above-described prior art, it is difficult to accurately determine the position of the heat generating portion of the thermal head during printing in order to operate the head portion. In some cases, the printing becomes lighter due to the displacement. Further, the conventional head-up mechanism has many problems in terms of workability.
First, in disassembly work such as removing screws during maintenance, there is a danger that the screws may fall into the printer during the work and cause a short circuit on the board and cause a failure, or the screws may be lost during the work. there were. Also, once disassembled, the position of the heat generating portion of the head is likely to shift. Further, if the head is frequently attached and detached, the FPC, the connector, and the like connected to the head are easily damaged.

In any case, the conventional head support and head-up mechanism cannot perform maintenance such as head cleaning, or even if it is possible, it involves cumbersome work, and the mechanism is easily complicated and large, and printing is difficult. There are many problems such as that the optimum position of the head for printing is easily shifted and the print quality is deteriorated.

Accordingly, the present invention is to solve the various problems of the related art at a time.
By simply adding a few parts to the lever-type head-up mechanism, you can increase the lift of the head, expose the surface of the head, and easily remove paper when a paper jam occurs without having to attach or remove the head. An object of the present invention is to provide a line thermal printer capable of performing maintenance such as head cleaning. Another object of the present invention is to provide a line thermal printer capable of maintaining a heating portion of a head with respect to a platen at an optimum position during printing and obtaining good printing quality.

Further, in a conventional mechanism for pressing a head against a platen, a structure in which a spring member and a member for holding the spring member are disposed above the head is generally used. However, according to the present invention, the above-described advantageous effects can be obtained with a simple structure without increasing the size of the printer.

Further, there has conventionally been a printer in which a paper cutter is fixedly attached to a printer. However, in such a printer, the paper cutter is an obstacle, and it is conceivable that the lifting amount of the head cannot be increased. However, the present invention is applicable to a printer having a paper cutter.

[0009]

According to the present invention, there is provided a line thermal printer comprising: (1) a platen rotatably supported by a frame;
The thermal head presses the platen
First position to press, thermal head moves away from platen
To the second position and the third position further away from the second position.
A head holding member movably supported by a frame;
Engages with the head holding member and locks the thermal head at the second position
A possible first lever member and a head holder for the frame
Auxiliary member that can move with the material, head holding member and auxiliary
Energize the member to separate it from the thermal head in the first position.
The biasing member that presses the thermal head against the platen and the thermal head
Auxiliary member for positioning to the first position or the second position
And a second lever member for restraining the
When the member is released from the second lever, the thermal
Is moved from the first position or the second position to the third position.
It is characterized by being present.

(2) A head holding portion supported by a frame
A support shaft for rotatably supporting the material and the auxiliary member.
It is characterized by that .

(3) The head holding member is a thermal head
The rotation angle between the first position and the third position is 30 degrees or more
It is characterized by.

(4) The head holding member is a thermal head
When the first position is on both sides in the line direction, the thermal head
So that the position where the plate and platen press against each other is the predetermined position.
A bearing that supports a hook or platen formed in a frame
The frame is provided with an engagement portion that fits
Characterized in that it has an abutting portion for abutting each of the portions.
You.

(5) The biasing member is a screw mounted on the support shaft.
It is a recoil spring .

(6) The second lever member is a lever part which can be manually operated by projecting a part of the auxiliary member , and a frame is provided with a restraining means for restraining the position of the auxiliary member. It is characterized by the following.

(7) A paper cutter for cutting the printing paper is mounted on the head holding member.

[0016]

According to the constitutions (1) and (2) of the present invention, since the fixing means for fixing the auxiliary member is a lever-type part called the second lever member, no tool or the like is required.
The fixing of the auxiliary member can be easily released and the auxiliary member can be rotated. Further, according to the configuration of the above (2), the head holding member
And the auxiliary member move integrally, so that the
Movement becomes easy. Further, in the above (3), the rotation angle of the thermal head becomes 30 degrees or more, and the thermal head surface is largely separated from the platen. Therefore, in this state, maintenance such as cleaning of the head surface can be easily performed. Further, the printer is likely to be large-sized simply by adding the auxiliary member and the second lever member. However, as in the configuration of (5) above, the auxiliary member is provided above the head and the head holding member by using a torsion coil spring. , The increase in the height of the printer can be suppressed and the size can be reduced.

Further, according to the present invention, as in the above configuration (4) , the thermal head is always held at a fixed position during printing by the engagement portion . And good printing quality can be stably obtained. In addition, special parts are attached to the part to be engaged with the engagement part.
Even if the setting is not made, rationalization can be achieved by adopting a configuration in which the thermal head is positioned by a part of the bearing that supports the platen . As another rationalization, according to the configuration of the above (6), the auxiliary member and the second lever member are made into one part, so that the second lever member becomes unnecessary.
According to the configuration (7), the paper cutter also rotates in conjunction with the thermal head. Therefore, the paper cutter is largely separated from the platen, and the paper cutter hinders the rotation of the thermal head. You can't move.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on embodiments. FIG. 1 is a plan view of an embodiment of the printer according to the present invention.
Is a front view of the printer, and FIG. 3 is a right side view of the printer. It should be noted that all the same numbers in the figures indicate the same items.

First, the appearance of the printer will be described with reference to FIGS. Reference numeral 1 denotes a frame formed by bending a sheet metal into a U-shape to form a bottom portion, a right side portion, and a left side portion. A platen (rubber roller) 2 is supported on the left and right side surfaces via a bearing. A manual knob 201 for manually turning the platen 2 is mounted on the right side of the platen 2, and a gear for driving the platen with a motor is mounted on the left side. Reference numeral 3 denotes a thermal head, which is usually fixed to the head fixing plate 300 and is treated as one component. Therefore, the component to which the thermal head 3 is fixed to the head fixing plate 300 is hereinafter referred to as a head portion. The center of this head is a support shaft
The head 405 is connected to the head holding member 4 by 405, and the head itself can swing with respect to the support shaft 405. Now, the width of the head holding member 4 is as shown in FIG.
The width of the head portion is set shorter than the width of the head portion, and the connecting portion with the head portion (the position of the support shaft 405) is disposed at a position shifted leftward from the center of the head holding member 4, and the head holding member 4 and the head portion are connected to the platen. The mechanism component for pressing the shutter 2 is concentrated on the right side of the printer.

Conventionally, in many line thermal printers, the width of a head holding member for applying a pressing force to a head is substantially the same as the width of a head portion in order to make the force pressing the head against the platen uniform in the line direction. Was set to However, when the head portion is pressed only by the center support shaft portion as in the present printer, the head portion only needs to be firmly held so as to be parallel to the platen at least when the head is pressed. The width of the head holding member 4 can be set short so that the head holding member 4 can be shifted to the right or left with respect to the head portion.

The mechanism by which the head of the printer is accurately parallel to the platen will be described later in detail. In this manner, an empty space surrounded by the thermal head 2, a mechanism for holding the head, and the left side surface of the frame 1 is formed in the leftward portion of the printer, and the motor 5 is arranged in this space. It is possible to provide a small printer with a small width without the motor 5 protruding outward. The power from the motor 5 is transmitted to the platen 2 via a gear train arranged on the left side of the frame 1.

Next, a method of attaching the motor 5 will be described. The surface on which the pinion is provided (the front surface of the motor) is screwed to the left side surface of the frame 1, and the surface without the pinion (the back surface of the motor) is screwed to a heat dissipation auxiliary plate 501 formed by bending a sheet metal into an L shape. The heat dissipation auxiliary plate 501 is screwed to the bottom of the frame 1. In the case of a line thermal printer such as this one, printing is performed while feeding paper, so that the motor is used in a continuous drive. For this reason, the motor generates heat at a high temperature, often causing a decrease in torque and a decrease in motor life.

However, in this printer, as described above, the heat of the motor 5 is also released from the back of the motor to the heat dissipation auxiliary plate 501 and the frame 1, so that the heat dissipation effect is much greater than when heat is radiated only from the front of the motor. Has improved.
Although this printer is a small line thermal printer driven by 24 volts, when the coil temperature inside the motor was measured in the actual printing state, it rose to a maximum of 130 ° C without the heat dissipation auxiliary plate 501. , Heat dissipation auxiliary plate 501
With the addition of, the temperature rose only up to 120 ° C.
This makes it possible to use a class E coil wire having a heat-resistant temperature of 125 ° C. or less.

Next, the mechanism of the head support will be described. Reference numeral 6 denotes an auxiliary member.
The head holding member 4 and the auxiliary member 6 are both rotatable about the position of the shaft 7 as a fulcrum. A spring member 8 (a torsion coil spring) is mounted on the shaft 7, and the arm of the spring is
When the auxiliary member 6 is fixed at a predetermined position as shown in FIG. 1, the head holding member 4 receives a force in the direction of the platen 2 by the spring force. Then, the head is pressed against the platen 2. 9 is the cam 90
1 is a first lever member, and is rotatably fitted within a range provided on a shaft provided on the right side of the frame 1. The head holding member 4 is provided with a second engaging portion 402 so as to engage with the cam portion 901 of the first lever member 9 and a second engaging portion 402 so as to engage with the auxiliary member 6. ing.
By operating the first lever member 9, the head portion can be pressed into contact with the platen 2 (head down state) or separated (head up state).

Reference numeral 10 denotes a detector of a microswitch, which is turned on and off in conjunction with the first lever member 9, and is controlled so as not to print in the head-up state. Reference numeral 11 denotes a second lever member for restraining and fixing the auxiliary member 6 at a predetermined position. The second lever member 11 is rotatably inserted in a range provided on a shaft portion provided on the auxiliary member 6, and has a force of the spring member 8. At the bottom of the frame 1. Therefore, in FIG. 2, when the second lever member 11 is rotated in the direction of the arrow, the fixing of the auxiliary member 6 is released, and the auxiliary spring 60 is released.
It rotates under the force of 1.

Next, the head-up and head-down states will be described with reference to FIGS. FIG. 4 is a left side view of the printer, in which a gear train for rotating the platen 2 can be seen. On the left side surface of the frame 1, a positioning portion 101 for positioning the head portion is formed in a groove shape. FIG. 5 is a right side view showing the head-up state in which the first lever member 9 is rotated and the head gap A is secured, and the degree determining part 10 is located at a position symmetrical to the degree determining part 101 described above.
2 is formed. Engaging portions 301 and 302 for positioning are provided as a pair on both sides of the head fixing plate 300 of the head portion so as to engage with the determining portions 101 and 102, respectively. Until the head-up state in FIG. 5, each of the engaging portions 301 and 302 moves within the degree determining portions 101 and 102 of the frame 1. In this way, in the head down state, the position of the head portion is positioned at a predetermined position. At this time, the thermal head 3 is firmly fixed so as to be parallel to the platen 2, and the force pressing the head portion, whose central portion is swingably supported, against the printer becomes uniform in the line direction. In addition, if the position of the heat generating portion of the thermal head 3 is set to the optimal position for printing with respect to the platen 2 in this head down state, even if the head up and down are repeated, the platen 2 and the thermal head Since the relative positional relationship of No. 3 is always constant, stable and good printing can be obtained.

Next, the structure of the head section of the printer will be described in more detail with reference to FIGS. First,
In FIG. 6, reference numeral 305 denotes a head cover formed by bending a stainless steel plate, and has bent portions 306 and 307 on the left and right. At the left and right ends of the back surface of the thermal head 3, steps 30 having substantially the same steps as the thickness of the head cover 305 are provided.
8, 309 are provided. A driver IC or FPC (not shown) is joined to the thermal head 3, and the joint between the driver IC and FPC is protected by a head cover 305. The head fixing plate 300 has positioning engaging portions 30 at symmetrical positions on both left and right sides.
1, 302 are provided, and a support shaft hole 303,
304 is provided. FIG. 7 is a diagram showing a configuration for holding the head unit. The bending portion of the head holding member 4 is provided with support shaft holes 403, 404, and the support shaft 405 is provided in the support shaft hole.
403 and 404 and support shaft holes 303 and 304 are passed through.

A male screw portion 406 is formed at one end of the support shaft 405, and a flange portion 407 is formed at the other end. A female screw is formed in the support shaft hole 404 that engages with the screw portion 406. The support shaft 405 is screwed to the head holding member 4.
Thus, the head portion is held by the head holding member 4.
Is set to be longer than the distance b outside the bent portion of the head fixing plate 300, and the support shaft holes 303 and 304 are
Is larger than the diameter of the head portion, the head portion is held with a certain gap vertically and horizontally.
Replace the head with a screwdriver or coin.
This can be easily performed by turning the 407 and attaching and detaching the support shaft 405.

Next, the operation of the present printer will be described based on a sectional view. FIG. 8 is a left sectional view of the printer. Reference numeral 12 denotes a paper ejection guide, which is attached to the inside of both side surfaces of the frame 1 for the purpose of preventing the printed paper from being caught in the platen 2 again. Paper guide 13 is frame 1
It is placed on the bottom of the camera. The paper guide 13 has two types of paper insertion sections 1301 and 1302. When ordinary thermal paper is used as printing paper, the thermal paper 14 is wound around the platen 2 through the paper insertion section 1301 as shown in FIG. Be mounted. When using thick printing paper such as the thermal label paper 1401, the thermal label paper 1401 is fed almost linearly through a paper passage hole formed in the bottom of the frame 1 and a paper insertion section 1302. At this time, the head cover 30
5 is the paper guide surface. In either case, the printing paper is sandwiched between the platen 2 and the thermal head 3, and is fed by frictional force due to rotation of the platen 2.

The position 310 of the heat generating portion of the thermal head 3
Is always kept at the optimum position during printing by the above-described determination mechanism. Reference numeral 1303 denotes a paper detector, which uses a reflection type photosensor. Reference numeral 1304 denotes an auxiliary roller for paper feeding. When the thermal paper 14 is inserted between the platen 2 and the auxiliary roller 1304, the paper is automatically fed by the rotation of the platen 2 and printing is started. The above is the printing operation in the head down state.

One feature of this printer is that the head is pressed against the platen by a torsion coil spring. As shown in the figure, by attaching a spring member 8 of a torsion coil spring to a fulcrum shaft 7, the spring is formed. A compact printer having a low height can be provided without being disposed above the head section. By the way, when printing is not performed for a long time, the first lever member 9 is operated to raise the head as shown in FIG. Then, a gap of about A = 1 mm to 3 mm is formed between the thermal head 3 and the platen 2 to prevent the platen 2 from being deformed. In this head-up state, the printing paper is moved to finely adjust the printing position.

When the second lever member 11 is operated, as shown in FIG. 9, the head rotates about the shaft 7 and moves largely away from the platen 2 to protrude upward from the printer body. become. This state is called a head open state and is distinguished from a head-up state by operating the first lever member 9. At this time, the rotation angle B of the thermal head 3 is 4
5 degrees.

In the conventional line thermal printer, the rotation angle B of the head at the time of head-up in normal operation is at most less than 30 degrees. Therefore, this rotation angle B is set to 30 degrees or more as in this example. Then, the thermal head 3 is separated from the platen 2 so that it cannot be obtained by the conventional lever operation, and the surface of the head is exposed. Therefore, by setting the head in the open state, the user can easily perform head cleaning with a swab or the like. Further, the head can be replaced or the paper can be removed at the time of paper jam (paper jam) by opening the head. In general, the frequency with which the head is opened is much lower than when the head is raised.Therefore, using a lever other than the lever for raising the head and changing the color for identification, etc. And the usability is improved.

Further, as an advantage of the head-up and head-open mechanism of the present construction, as shown in FIG. 10, even when the auxiliary member 6, the second lever member 11, and the auxiliary spring 601 are removed, the frame If the spring member 8 is set so as to urge the bottom surface of the first lever 1, the head-up and head-down operations by the first lever member 9 can be performed in exactly the same manner. This is because when developing a product based on this printer, if a low-cost, disposable printer is made that requires no maintenance, the auxiliary member 6 is required.
And the second lever member 11 and the auxiliary spring 601 are removed.
On the other hand, if you make an advanced machine that needs maintenance,
The configuration may be changed depending on the application, such as a complete configuration. That is, by using the same parts for the low-priced machine and the advanced machine, the cost can be reduced due to the mass production effect.

Next, a method of fixing the paper guide 13 will be described with reference to FIG.
This will be described with reference to FIG. The platen 2 is mounted on the frame 1 by placing the paper guide 13 on the bottom surface of the frame 1 and fitting the left and right platen bearings 202 to the corresponding left and right engaging portions 1305 and 103 respectively. Therefore, the left and right bearings
Reference numeral 202 supports the platen 2 at the same time as preventing the paper guide 13 from slipping upward, and the paper guide 13 is locked to the frame 1. With the above-described configuration, the present printer does not require a medium such as a screw when fixing the paper guide, thereby improving the assemblability and reducing the assembling cost. Further, if the platen portion is removed, the paper guide 13 can also be removed, so that maintenance of the paper detector 1303 and the auxiliary roller 1304 provided on the paper guide 13 and removal of the paper dust are easy. Further, the platen bearing 202 and the paper guide 13
, The gap between the paper guide surface and the surface of the platen 2 can be accurately obtained.

The printer can be equipped with a paper cutter and a motor cover. These will be described with reference to FIGS. As shown in Fig. 12, the paper cutter 15 has fixing screws.
The screw is fixed to the head holding member 4 by 1501.
Conventionally, the paper cutter is generally fixed to the upper part of the frame or the case of the printer. However, the paper cutter is mounted on the rotatable head holding member 4 as in the present invention, so that the head-up operation is performed. Since the printing paper is slightly separated from the platen 2 as in the case of the head, the printing paper hardly gets stuck on the paper cutter 15 and the insertability of the printing paper is improved. Further, in the head open state, the paper cutter 15 is far away from the platen 2 and does not hinder the removal of the paper or the cleaning of the head. In addition, the paper cutter 15 largely covers the head portion, and not only cuts the printed paper by hand cutting, but also protects the head portion and prevents foreign matters from falling.
In the thermal printer, the head is hot, so
Safety is also considered so as not to touch the head directly with the hand. FIG. 13 shows a side surface of the motor cover 16. As shown in the figure, the frame 5 is fastened together with the motor 5 from the side of the frame 1 by a fixing screw 1601. The motor cover 16 prevents the motor 5 from directly touching the motor 5 because the motor 5 generates heat at a high temperature, and also covers the gear train so as to prevent foreign matter from being caught in the gear. Fig. 14 shows the paper cutter 15 and motor cover 16.
FIG. 1 is a plan view of a printer equipped with a printer. Although an example of a hand-cut paper cutter is shown in the drawing, an automatic cutter unit driven by a motor can be attached to the head holding member 4.

The present invention has been described with reference to one embodiment. Next, another embodiment of the present invention will be described. 15 to 16 show a second embodiment. Head holding member 17
The first lever member 18 is engaged with the first lever member 18 to perform head-up and head-down operations, but in the second example, the width of the auxiliary member 19 is equal to the width of the head holding member 17. Larger, the second lever member 20 is attached to the right side of the frame like the first lever member. By adopting such a configuration, the operation unit can be arranged near, and the degree of freedom in case design is increased. However, auxiliary members
Since the width of 19 is long, the auxiliary member 19 is easily twisted and deformed by the spring force. Therefore, the shaft 21 serving as the rotation fulcrum is not a round shaft but a deformed shaft, and the shape of the shaft hole of the auxiliary member 19 is the same as that of the deformed shaft, and the shaft 21 and the auxiliary member 19 are connected and integrally rotated. By doing so, the strength is increased.

The head opening operation is performed by releasing the fixing of the auxiliary member 19 by rotating the second lever member 20 in the direction of the arrow in FIG. The positioning of the head portion is performed by abutment of the degree determining portion 22 attached to the side surface of the frame with the thermal head 23. Note that the degree determination unit 22 can finely adjust the position while printing so as to be at the optimum position for printing.

Next, rationalization will be described with reference to third and fourth embodiments. FIG. 17 shows a third embodiment. Numeral 24 denotes bearings for supporting the shaft portions at both ends of the platen, which are paired on the left and right. A part of this bearing 24 is
The thermal head 25
A position determining part for determining the position is formed. As described above, the determining unit, which is one of the features of the present invention, can form the determining unit by simply changing a part of the existing part without making a new part. .

Further, since the bearing is a component fixed coaxially with the platen, it is easy to accurately determine the relative position with respect to the platen. FIG. 18 is a perspective view of a part of the printer according to the fourth embodiment. A part of the auxiliary member 26 protrudes to form a lever 2601 that can be manually operated. Thereby, the auxiliary member and the second lever member described in the first embodiment can be made into one part, and the number of parts can be reduced. Normally,
The dowel 2602 provided on the auxiliary member 26 is engaged with the dowel hole 27 provided on the side surface of the frame to lock the auxiliary member 27.
Next, when the head is in the open state, if the lever 2601 is strongly turned in the direction of the arrow, the dowel 2601 comes off the dowel hole 27,
The engagement with the dowel hole 28 stops. As a result, the auxiliary member 26 is fixed at each position during normal operation and when the head is open.

The present invention has been described through several embodiments. By additionally mounting the auxiliary member and the second lever member on the conventional printer, the lifting amount of the head portion is increased (the head is in an open state), the surface of the head is exposed, and the paper can be easily removed when paper jam occurs. Maintenance such as cleaning can be performed, and at the time of printing, the position of the head unit with respect to the platen is maintained at an optimum position, and a series of effects of obtaining good printing quality is not limited to the embodiment described in the text. .

[0042]

As described above, the line thermal printer of the present invention has a head holding member, an auxiliary member, and a second lever member, which are unique to the present invention, and can be operated by a simple lever operation that does not require tools or the like. Can be lifted upward, and the effect of facilitating maintenance such as removal of paper in the event of paper jam and head cleaning can be obtained.

Further, in such a mechanism in which the head portion is largely moved, the relative position between the head and the platen is easily shifted. However, the degree determining portion provided in a part of the printer main body and the engagement portion provided in the head portion are provided. Since the parts are in contact with each other, during printing, the position of the head with respect to the platen is maintained at an optimum position, and good printing quality is obtained.

As an indirect effect, even if the auxiliary member and the second lever member are removed, a normal head-up operation can be performed, and a low-cost printer can be developed using the same components.

Further, since the lever for opening the head and the lever for raising the normal head are separate levers, it is difficult for an operation error to occur and the usability is good.

Further, since the paper cutter is mounted on the head holding member, the paper cutter is largely separated from the platen when the paper is removed or the head is cleaned while the head is open, so that the paper cutter does not become an obstacle. As described above, the present invention has a great effect.

[Brief description of the drawings]

FIG. 1 is a plan view of a printer showing one embodiment of the present invention.

FIG. 2 is a front view of the same printer as FIG. 1;

FIG. 3 is a right side view of the same printer as FIG. 1;

FIG. 4 is a left side view of the same printer as FIG. 1;

5 is a right side view of the same printer as in FIG. 1 (when the head is up).

FIG. 6 is a configuration diagram of a head unit of the same printer as in FIG. 1;

FIG. 7 is a configuration diagram of a head holding unit of the same printer as in FIG. 1;

FIG. 8 is a left sectional view of the same printer as in FIG. 1 (when the head is down).

FIG. 9 is a left sectional view of the same printer as in FIG. 1 (when the head is open).

FIG. 10 is a left sectional view of the same printer as that of FIG. 1 (when the head open mechanism is removed).

FIG. 11 is a perspective view of a paper guide unit of the same printer as in FIG. 1;

FIG. 12 is a left sectional view of the same printer as in FIG. 1 (when a paper cutter is mounted).

FIG. 13 is a left side view of the same printer as in FIG. 1 (when a motor cover is attached).

FIG. 14 is a plan view of the same printer as that of FIG. 1 (when a paper cutter and a motor cover are attached).

FIG. 15 is a perspective view of a printer showing a second embodiment.

FIG. 16 is a sectional view of the same printer as FIG.

FIG. 17 is a sectional view of a printer according to a third embodiment.

FIG. 18 is a partial perspective view of a printer showing a fourth embodiment.

[Explanation of symbols]

 1 Frame 101, 102 degree determining part 2 Platen 201 Manual knob 202 Platen bearing 3 Thermal head 300 Head fixing plate 301, 302 Engagement part 305 Head cover 4 Head holding member 405 Support shaft 5 Motor 501 Radiation auxiliary plate 6 Auxiliary member 601 Auxiliary spring 7 axis 8 spring member 9 first lever member 11 second lever member 13 paper guide 14 thermal paper 1401 thermal label paper 15 paper cutter 16 motor cover 17 head holding member 18 first lever member 19 auxiliary member 20 second lever member 21 shaft 22 Degree setting part 23 Thermal head 24 Bearing 25 Thermal head 26 Auxiliary member 27, 28 Dowel hole

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B41J 25/304 B41J 2/32

Claims (7)

(57) [Claims] A platen rotatably supported by a frame.
And a thermal head , and the thermal head supports the thermal head.
A first position for pressing the Latin, wherein the thermal head is
A second position separated from the platen, and from the second position
It is movably supported by the frame to the third position further apart.
And the thermal head engaged with the head holding member and
A first lever member which can be locked at two positions, and which can be moved together with the head holding member with respect to the frame;
Auxiliary member, and the head holding member and the auxiliary member are separated from each other.
Force the thermal head at the first position to the platen.
An urging member for pressing the thermal head, the thermal head being in the first position or the second position.
The auxiliary member is restrained at a predetermined position so that the
The auxiliary member is released from the restriction by the second lever.
And the thermal head is in the first position or the first position.
Being movable from the second position to the third position.
Line thermal printer. 2. The head support supported by the frame.
A support shaft for rotatably supporting the holding member and the auxiliary member.
2. The line thermal printer according to claim 1, wherein the line thermal printer is provided. 3. The thermal head according to claim 2, wherein the head holding member is a thermal head.
The rotation angle between the first position and the third position of the pad is 30 degrees or more.
3. The line thermal pudding according to claim 2, wherein
Ta. 4. The thermal head according to claim 1, wherein the head holding member is a thermal head.
At the first position on both sides in the line direction of the pad,
The pressing position between the thermal head and the platen is
Hook or front part formed on the frame to be in position
An engagement portion that fits with a bearing that supports the platen.
The frame is in contact with each of the engagement portions
4. The method according to claim 1, further comprising a contact portion.
Line thermal printer. 5. The urging member is mounted on the support shaft.
3. The torsion coil spring according to claim 2, wherein
Line thermal printer. 6. The second lever member is a lever portion which is formed by projecting a part of the auxiliary member and can be operated by hand.
3. The line thermal printer according to claim 1, wherein a restraining means for restraining a position of the auxiliary member is provided on the frame . 7. The printing apparatus according to claim 1, wherein a paper cutter for cutting printing paper is mounted on the head holding member.
To 5 line thermal printers.