JP2003063048A - Thermal printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermal printer which has a high operability with simple structure and can surely lock up frames each other. SOLUTION: The thermal printer 1 is constituted of a thermal head 3 conducting thermal recording on recording paper, a platen 31 to press the recording paper against the thermal head 3, a body frame 2 to carry the thermal head 3, a sub-frame 30 to carry the platen 31, a rotating shaft 21 supporting the body frame 2 and the sub-frame 30 mutually freely openable and closable, a lock shaft 40 which is disposed on the sub-frame 30, and regulated the displacement in the rotation periphery direction but allowed the displacement in the rotation radius direction, and engagement parts 23, 24 which are disposed on the body frame 2 and engaged with the lock shaft 40 and regulate the displacement of the lock shaft to the rotation periphery direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal printer having a frame opening / closing mechanism in which a thermal head and a platen can be separated from each other.

[0002]

2. Description of the Related Art In a frame opening / closing mechanism, a large space can be secured between a thermal head and a platen, so that maintenance work such as paper setting and jam removal is facilitated.

As an example of the prior art, Japanese Patent Laid-Open No. 3-763
No. 70 describes a facsimile apparatus having a double-door structure in which a thermal head is fixed to a main body, a platen is attached to a paper cover, and a printing section cover engages with the paper cover.

Further, Japanese Patent Application Laid-Open No. 11-99726 describes a thermal printer in which a thermal head is provided on a lid, a platen is attached to the main body, and the pressing force of the thermal head changes as the upper cover is opened and closed. ing.

[0005]

In the conventional thermal printer, only the forward conveyance of the sheet is assumed, and when the sheet is conveyed in the reverse direction, the platen shaft is displaced due to the reaction force, and the sheet is conveyed. This will cause transport problems and jams. Therefore, in order to reduce the margin of the leading end of the receipt, it is impossible to carry out the backward conveyance in which the leading end of the sheet cut by the cutter or the like is returned to the printing position of the thermal head.

Further, in the frame opening / closing mechanism, when the paper is conveyed in the forward direction and the backward direction, it is necessary to reliably lock the frames to prevent the positional displacement between the thermal head and the platen.

However, in order to reliably lock the frames together, a complicated locking mechanism is required, and there is a problem that an increase in cost cannot be avoided.

An object of the present invention is to provide a thermal printer having a simple structure, high operability, and capable of reliably locking the frames to each other.

[0009]

Further, according to the present invention, a thermal head for performing thermal recording on a recording sheet, a platen for pressing the recording sheet against the thermal head, and one of the thermal head and the platen are mounted. A first frame, a second frame for mounting the other one of the thermal head and the platen, a rotation shaft for rotatably supporting the first frame and the second frame, and a second frame. A lock member that is allowed to be displaced in the radial direction of rotation, and an engagement member that is provided on the first frame and that can engage with the lock member. Both ends of the lock member are opposite to each other in the second frame. A support member for supporting the lock member so that the lock member can swing freely, and a first lock member
An urging member for urging the end toward the rotation axis is provided, and the first frame includes a first engaging member that restricts displacement of the first end of the lock member and a second lock member. The thermal printer is provided with a second engaging member that regulates the displacement of the end.

According to the present invention, since the first frame and the second frame are rotatably supported with respect to each other, a wide space can be secured between them, so that maintenance work such as paper setting and jam removal is easy. become.

Further, when the first frame and the second frame are closed to each other, the engaging member provided on the first frame engages with the lock member provided on the second frame, so that the first frame and the second frame. The relative position between and is determined. As a result, the relative position between the thermal head and the platen is also determined, so that stable printing operation and the forward and backward conveyance of the paper can be realized.

Further, by supporting the lock member so that both ends thereof can swing in opposite directions, when one end of the lock member is displaced, the other end is displaced in the opposite direction, so that either one of the ends is rotated. When biased toward, the opposite biasing force can be applied to the other end. Therefore, the urging force can be applied to both ends only by providing the urging member at one end.

Further, when the first frame and the second frame are closed to each other, the first engaging member regulates the displacement of the first end and the second engaging member regulates the displacement of the second end. Both ends of the lock member are reliably positioned. As a result, the relative position between the first frame and the second frame can be reliably regulated.

Further, according to the present invention, a thermal head for performing thermal recording on a recording sheet, a platen for pressing the recording sheet against the thermal head, and a first frame for mounting one of the thermal head and the platen are provided. A second frame for mounting the other one of the thermal head and the platen, a rotation shaft for rotatably supporting the first frame and the second frame, and a second frame provided in the second frame for rotating in the circumferential direction. A lock member whose displacement is restricted and which is allowed to be displaced in the radial direction of rotation, and an engagement which is provided on the first frame and engages with the lock member to restrict the displacement of the lock member in the circumferential direction of rotation. A support member for supporting the lock member such that both ends of the lock member can swing in opposite directions, and a first shaft of the lock member on the second frame. A biasing member for biasing the lock member is provided, and the first frame restricts the displacement of the first end of the lock member and the displacement of the second end of the lock member on the first frame. A thermal printer is provided with a second engaging member.

According to the present invention, since the first frame and the second frame are rotatably supported with respect to each other, a wide space can be secured between them, so that maintenance work such as paper setting and jam removal is easy. become.

Further, when the first frame and the second frame are closed to each other, the engaging member provided on the first frame engages with the lock member provided on the second frame, and the lock member is rotated in the circumferential direction. By regulating the displacement, the relative position between the first frame and the second frame is determined. As a result, the relative position between the thermal head and the platen is also determined, so that stable printing operation and the forward and backward conveyance of the paper can be realized.

Further, by supporting the lock member so that both ends can swing in opposite directions, when one end of the lock member is displaced, the other end is displaced in the opposite direction, so that either one of the ends is rotated. When biased toward, the opposite biasing force can be applied to the other end. Therefore, the urging force can be applied to both ends only by providing the urging member at one end.

When the first frame and the second frame are closed to each other, the first engaging member regulates the displacement of the first end, and the second engaging member regulates the displacement of the second end. Both ends of the lock member are reliably positioned. As a result, the relative position between the first frame and the second frame can be reliably regulated.

Further, the present invention is rotatably supported around the rotating shaft,
An operation lever having a cam surface that contacts the lock member is provided, and the cam surface displaces the lock member engaged with the first engagement member to release the engagement when the frame of the operation lever is opened, and the lock member The second frame is rotated in the opening direction via the.

Further, the cam surface comes into contact with the lock member to rotate the second frame in the opening direction, whereby the movement of the operation lever and the movement of the second frame are interlocked with each other, so that the operability is improved. To do.

[0021]

1 is a perspective view showing an embodiment of the present invention, and FIG. 2 is a perspective view showing a state in which a subframe on the platen side is opened. 3 is a perspective view showing a state in which the subframe is removed, FIG. 4 is a perspective view showing the subframe, and FIG. 5 is a perspective view showing the subframe from another direction. FIG. 6A is a side view showing a state where the subframe is opened, and FIG. 6B is a side view showing a state where the subframe is closed.

The thermal printer 1 includes a thermal head 3
The main frame 2 on which the subframe 30 is mounted and the subframe 30 on which the platen 31 is mounted are provided. The subframe 30 is rotatably supported with respect to the main frame 2 and constitutes a frame opening / closing mechanism.

The main body frame 2 is composed of both side plates and a connecting plate that connects the side plates together, and a sheet conveying path is formed along the inside of both side plates.

In the vicinity of the center of the inside of the main body frame 2, FIG.
As shown in (a), a line-type thermal head 3 for performing thermal recording on a recording sheet is attached. A cutter unit 4 for cutting the recording paper recorded by the thermal head 3 is attached to the paper discharge surface side of the main body frame 2.

The subframe 30 is, as shown in FIG.
It is composed of both side plates located outside the side plates of the main body frame 2 and a connecting plate connecting the side plates. A rotating shaft 21 is attached to the lower portion of the side plate of the sub-frame 30, and is pivotally supported by a support hole 22 formed in the lower portion of the side plate of the main body frame 2.

A platen shaft 32 is rotatably supported by bearings 33 and 34 on the upper portion of the side plate of the subframe 30. A driven gear 32a is attached to one end of the platen shaft 32, and meshes with a drive gear (not shown) provided in the main body frame 2 with the subframe 30 closed.

A lock shaft 40 is arranged between the platen 31 and the rotary shaft 21. Lock shaft 40
Are swingably supported by a support plate 41 cut and raised near the center of the connecting plate of the subframe 30.

Guide holes 43 and 44 through which the end portions 40a and 40b of the lock shaft 40 pass are formed near the center of the side plate of the subframe 30. Guide hole 43,
44 is formed as an elongated hole having a width substantially the same as the outer diameter of the lock shaft 40, and the longitudinal directions of the guide holes 43, 44 substantially coincide with the radial direction of rotation about the rotary shaft 21. Therefore, the end portions 40a and 40b of the lock shaft 40 are restricted from being displaced in the rotation circumferential direction about the rotation shaft 21 by the guide holes 43 and 44, and are allowed to be displaced in the rotation radius direction. The lock shaft 40 moves like a seesaw around the support plate 41 as a fulcrum, and the ends 40a and 40b are displaced in opposite directions.

Further, as shown in FIG. 5, a tension coil spring 42 is bridged between the end 40b of the lock shaft 40 and the rotating shaft 21, and the end 40b is attached toward the center of rotation. I am energetic. Therefore, at the opposite end 40a,
A biasing force acts in a direction away from the rotating shaft 21.

The operating lever 47 is pivotally supported around the rotary shaft 21. As shown in FIG. 2, the end surface of the operation lever 47 is provided with a contact portion 46 capable of contacting a bent piece 49 bent outward from the side plate of the subframe 30. When the sub-frame 30 is stored in the main body frame 2, the bending piece 49 is provided with the opening / closing switch 8 installed in the main body frame 2.
It also has a function of touching the detection part of.

A cam surface 45 that engages with the end portion 40a of the lock shaft 40 is formed inside the operation lever 47. On the cam surface 45, the sub frame 30 is the main body frame 2
When the operation lever 47 is opened to the front in the state of being housed in, the inclined surface is formed so as to displace the end portion 40a toward the rotating shaft 21.

On the other hand, U-shaped grooves 13 and 14 are formed on both side plates of the main body frame 2 so as to fit substantially with the bearings 33 and 34 of the subframe 30 when the subframe 30 is housed in the main body frame 2. , The relative position of the sub-frame 30 and the main body frame 2 is regulated.

Further, below the grooves 13 and 14, engaging portions 23 and 24 capable of engaging with the end portions 40a and 40b of the lock shaft 40 of the subframe 30 are formed. Engaging part 23
Is a U-shaped groove 23a opened upward and an end portion 40b of the lock shaft 40 when the sub-frame 30 is housed.
Has a slanted surface 23b for smoothly guiding the groove to the groove 23a. The engaging portion 24 has a U-shaped groove 24a opened downward.
And an inclined surface 24b that smoothly guides the end portion 40a of the lock shaft 40 to the groove 24a when the subframe 30 is stored.

Next, the operation will be described. As shown in FIG. 6A, when the sub-frame 30 is opened with respect to the main body frame 2, a large space is secured between the thermal head 3 and the platen 31. Maintenance work becomes easy.

First, when the sub-frame 30 is stored in the main body frame 2, the user holds the operating lever 47 of the sub-frame 30 and angularly displaces it clockwise in FIG. 6A. Then, the contact portion 46 of the operating lever 47 contacts the bent piece 49 of the sub-frame 30, and the operating lever 47 is further contacted.
When is displaced, the contact portion 46 pushes up the bending piece 49, and the sub-frame 30 follows the operation lever 47 and rotates. Then, the bearing 3 of the sub-frame 30
3, 34 are introduced into the grooves 13, 14 of the body frame 2, and the ends 40a, 40b of the lock shaft 40 contact the inclined surfaces 24b, 23b, respectively. At this time, the end portion 40b is biased toward the rotary shaft 21 and the end portion 40a is biased toward the rotary shaft 21 by the tension coil spring 42.

When the user pushes the outer surface of the sub-frame 30, the end portions 40a, 40b resist the biasing force and the inclined surface 24
b, 23b, and finally grooves 24a, 23a
Is stored in. At this time, as shown in FIG. 6 (b), the grooves 24 a and 23 a restrict the displacement of the lock shaft 40 in the rotation circumferential direction.
The relative position with is fixed, and the thermal head 3 and platen 3
The relative position to 1 is also determined. As a result, it is possible to realize stable printing operation and the forward and backward conveyance of the paper.

Next, when the subframe 30 is opened from the main body frame 2, the user operates the operation lever 4 of the subframe 30.
7 is gripped and angularly displaced counterclockwise in FIG. 6 (b). Then, the cam surface 45 of the operating lever 47 contacts the end portion 40a of the lock shaft 40, and the operating lever 4
When opening 7, the end portion 40a starts to be displaced toward the rotary shaft 21 due to the contact with the cam surface 45, and finally comes out of the groove 24a against the biasing force of the tension coil spring 42. Similarly, the end portion 40b resists the urging force of the tension coil spring 42 by the seesaw motion of the lock shaft 40, and thus the groove 23a.
Get out of.

When the user further opens the operation lever 47,
The engagement between the end portions 40a, 40b and the engagement portions 23, 24 is released, and the end of the cam surface 45 contacts the end portion 40a of the lock shaft 40 to rotate the subframe 30 in the opening direction. You can Therefore, the movement of the operation lever 47 and the movement of the sub-frame 30 are interlocked with each other, and the operability is improved.

At this time, since the operating lever 47 is pivotally supported around the rotary shaft 21, the turning force of the operating lever 47 is transmitted to the subframe 30 without any loss, so that the user can easily operate the subframe 30. It can be opened.

[0040]

As described above, according to the present invention, when the first frame and the second frame are closed, the engaging member provided on the first frame engages with the lock member provided on the second frame. By doing the first frame and the second
The relative position with respect to the frame is determined.

For example, in a thermal printer in which a thermal head is mounted on the first frame and a platen is mounted on the second frame, the relative position between the thermal head and the platen is determined by the locking of the frames, so stable printing operation and paper It is possible to realize forward transport and reverse transport of.

Further, by supporting the lock member so that both ends thereof can swing in opposite directions, when one end of the lock member is displaced, the other end is displaced in the opposite direction. When biased toward, the opposite biasing force can be applied to the other end. Therefore, the urging force can be applied to both ends only by providing the urging member at one end.

Further, when the first frame and the second frame are closed to each other, the first engaging member regulates the displacement of the first end and the second engaging member regulates the displacement of the second end. Both ends of the lock member are reliably positioned. As a result, the relative position between the first frame and the second frame can be reliably regulated.

In this way, a low-cost frame lock mechanism can be realized with a simple structure. In addition, an operation lever having a cam surface that comes into contact with the lock member is pivotally supported around the rotating shaft, and the cam surface releases the engagement between the lock member and the first engagement member by the frame opening operation of the operation lever. At the same time, the engagement between the lock member and the second engagement member can be released. Therefore, the disengagement of both ends can be performed only by providing the operation lever at one end.

Further, the cam surface comes into contact with the lock member to rotate the second frame in the opening direction, whereby the movement of the operation lever and the movement of the second frame are interlocked with each other, so that the operability is improved. To do.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention.

FIG. 2 is a perspective view showing a state in which a subframe on the platen side is opened.

FIG. 3 is a perspective view showing a state in which a subframe is removed.

FIG. 4 is a perspective view showing a subframe.

FIG. 5 is a perspective view showing the sub-frame from another direction.

FIG. 6 (a) is a side view showing a state in which a sub frame is opened, and FIG. 6 (b) is a side view showing a state in which the sub frame is closed.

[Explanation of symbols]

1 thermal printer 2 body frame 3 thermal head 4 cutter unit 13,14 groove 21 rotation axis 22 Support hole 23, 24 Engagement part 30 subframes 31 Platen 32 platen shaft 32a driven gear 33,34 bearing 40 lock shaft 41 Support plate 42 tension coil spring 43,44 Guide hole 45 Cam surface 46 abutment 47 Control lever 49 bent pieces

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 2C058 AB10 AB12 AC06 AD01 AE09                       AF31 AF44 AF54 DA10 DA22                       DA26 DA32 DB03                 2C061 AQ04 BB10 BB12 BB31                 2C065 AA01 AB01 CC02 CC05 CC07                       CC10 CC25 CC32

Claims (3)

[Claims] 1. A thermal head for performing thermal recording on a recording sheet; a platen for pressing the recording sheet against the thermal head; a first frame for mounting one of the thermal head and the platen; a thermal head; A second frame for mounting the other platen, a rotation shaft for rotatably supporting the first frame and the second frame, and a second frame provided on the second frame and permitting displacement in a rotation radius direction. And a locking member provided on the first frame and engageable with the locking member. The locking member is provided on the second frame so that both ends of the locking member can swing in opposite directions. And a biasing member for biasing the first end of the lock member toward the rotation axis. The first frame is provided with a support member for supporting the lock member. Thermal printer of the first engagement member, characterized in that the second engaging member for restricting the displacement of the second end of the locking member is provided to regulate the displacement. 2. A thermal head for performing thermal recording on a recording sheet, a platen for pressing the recording sheet against the thermal head, a first frame for mounting one of the thermal head and the platen, a thermal head, and A second frame for mounting the other platen, a rotation shaft for rotatably supporting the first frame and the second frame, and a second frame provided on the second frame and restricted in displacement in the rotation circumferential direction. And a locking member that is allowed to be displaced in the radial direction of rotation, and an engagement member that is provided on the first frame and that engages with the locking member and restricts displacement of the locking member in the circumferential direction of rotation. The second frame includes a support member for supporting the lock member so that both ends of the lock member can swing in opposite directions, and a first end of the lock member facing the rotation axis. An urging member for urging is provided, and the first frame includes a first engaging member that restricts displacement of the first end of the lock member and a second engaging member that restricts displacement of the second end of the lock member. A thermal printer comprising: an engaging member. 3. An operating lever, which is pivotally supported around a rotating shaft and has a cam surface that comes into contact with a lock member, wherein the cam surface engages with the first engaging member during a frame opening operation of the operating lever. 3. The thermal printer according to claim 1, wherein the lock member is displaced to release the engagement, and the second frame is rotated in the opening direction via the lock member.