JP2002178594A - Cover of printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a cover of a printer in which an urging member, i.e., a coil spring can be fixed easily between a frame and a head fixing plate having a print head fixed rotatably to the frame. SOLUTION: The cover of a printer comprises a frame 17 having side plates 17d and 17e facing each other, and a head fixing plate 25 having a thermal head 26 fixed rotatably to the side plates 17d and 17e through a supporting shaft 18, and a coil spring 23 stooped between the frame 17 and the head fixing plate 25 and urging the head fixing plate 25 resiliently against the frame 17. The frame 17 is provided with a protrusion 17k abutting against the head fixing plate 25 through rotation thereof. The head fixing plate 25 is provided with a first rotary stop abutting against the protrusion 17k in a first attitude to regulate rotation of the head fixing plate 25, and the head fixing plate 25 rotated further from the first attitude to the frame 17 side while resisting against resiliency of the coil spring 23 is provided with a second rotary stop engaging with the protrusion 17k in a second attitude by sliding in the axial direction of the supporting shaft 18.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal printer, and more particularly, to a structure of a cover of a thermal printer having a line type printing mechanism.

[0002]

2. Description of the Related Art In recent years, with the progress of computerization in society, demand for printers, which are one of information output devices, is increasing in various fields. Thermal printers have the features of being small, lightweight, and easy to maintain, and their use is being expanded to personal computer output devices, measuring instruments, medical equipment, financial terminals, POS terminals, and the like. .

[0003] This type of thermal printer mainly comprises a printer main body and a cover body which is attached to the printer main body so as to be openable and closable around a hinge shaft.
The printer body includes a platen roller. The platen roller has a rubber-coated surface, is rotatably supported by the printer main body, and feeds the paper.

[0004] The cover body includes a frame made of sheet metal, and a head mounting plate having a thermal head mounted on the frame via a plurality of coil springs so as to be elastically urged.

When the cover body is closed by the printer body, the paper is elastically pressed and held between the rotating platen roller and the thermal head of the head mounting plate supported by the frame, and according to the print record information. The recording is performed on the paper by the heated thermal head. The print-recorded paper is discharged to the outside by a paper feed roller (not shown).

[0006]

In such a thermal printer, a coil spring is indispensable in order to keep the pressure of the thermal head pressed against the platen roller across the paper. However, in response to recent miniaturization and thinning of thermal printers, the distance between the frame and a head mounting plate rotatably supported by the frame has also become narrower, and a plurality of coil springs have been provided in this narrow gap. There has been a problem that the work for assembling has become more and more difficult, and a large jig has to be prepared for the incorporation.

SUMMARY OF THE INVENTION An object of the present invention is to provide a thermal printer in which a coil spring is easily mounted between a frame and a head mounting plate having a print head rotatably supported by the frame. To provide.

[0008]

As a first means for solving the above problems, a frame having side plates facing each other, and a print head rotatably provided on the side plates via a support shaft. A head mounting plate having: and a biasing member engaged between the frame and the head mounting plate, the biasing member elastically biasing the head mounting plate with respect to the frame. The head mounting plate is provided with a restricting portion capable of contacting the head mounting plate, and the head mounting plate is provided with a rotation locking portion for restricting the rotation of the head mounting plate, and the head mounting plate is provided with a biasing member. It is rotated by being resiliently pressed toward the frame while resisting the elastic urging force, and is slid in the axial direction of the support shaft so that the rotation locking portion engages with the restricting portion.

As a second solution, a frame having side plates facing each other, a head mounting plate having a print head rotatably provided on a side plate via a support shaft, a frame and a head mounting are provided. A biasing member engaged between the plate and the frame, the biasing member elastically biasing the head mounting plate against the frame; The head mounting plate is provided with first and second rotation locking portions for restricting rotation of the head mounting plate, and the first rotation locking portion abuts on the restriction portion. Then, the head mounting plate is rotated from the first posture by being resiliently pressed toward the frame side while resisting the elastic urging force of the urging member, and slid in the axial direction of the support shaft. Is moved to the second posture, and in this second posture, Second pivot locking portion is one that was to engage the control unit.

As a third solution, the regulating portion is formed by projecting at least one part of the side plate portion, and the head mounting plate is formed by bending both ends on the side where the longitudinal direction of the print head is located, A bearing plate portion formed so as to be able to support the support shaft facing the side plate portion, and a print head is arranged on one side of the head mounting plate, and the other edge of the head mounting plate is oriented in the same direction as the bearing plate portion. A first turning locking portion is formed by a bent base portion of the bearing plate portion, and a second turning locking portion is formed by the wall portion. It is.

As a fourth solution, the wall portion is formed in a belt shape by bending the edge of the head mounting plate along the longitudinal direction of the print head.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A thermal printer according to an embodiment of the present invention will be described below with reference to FIGS. As shown in FIG. 1, the thermal printer mainly includes a printer main body 12 and a cover body 16 that can be opened and closed with respect to the printer main body 12 about a hinge axis.
The printer body 12 is made of sheet metal and has a rectangular bottom plate (not shown), and first and second side plates 30b and 30c bent upward at substantially right angles from both ends of the bottom plate.
And an inclined wall 30m bent at a substantially acute angle along the rear side edge of the bottom plate.

A platen roller 35 whose surface is made of an elastic member such as rubber is rotatably supported between the first and second side plate portions 30b and 30c. Platen roller 3
The metal rotary shaft 35 a is attached at one end to a part of the illustrated gear group 55, and the platen roller 35 is rotated via the gear group 55 by the driving force of the stepping motor 54. . Further, between the first and second side plate portions 30b and 30c, a rotatable thin metal turning bar 31 is rotatably supported near the upper portion of the platen roller 35.

The first and second lever arms 44 and 46 are
Attached to each end of a lever shaft 42 pivotally supported between the first and second side plate portions 30b, 30c so as to be along the first and second side plate portions 30b, 30c, respectively, and to be rotatable. Has become. Lock claw receiving portions 44b, 46b are formed at the distal ends of the first and second lever arms 44, 46, respectively.
Further, the lock claw receiving portion 46b of the first lever arm 44
, A lock release knob 44c is formed.

Next, as shown in FIGS. 1 to 5, the cover body 16 includes a frame 17 made of sheet metal, a head mounting plate 25 also made of sheet metal, a thermal head (print head) 26, Shaft 18 made of shaft made of
And a plurality of coil springs (biasing members) 23 and a support 27 made of resin. Frame 1
Reference numeral 7 denotes a substantially rectangular flat plate portion 17a, side wall portions 17b and 17c bent downward at substantially right angles from both ends on the front side of the flat plate portion 17a, and a narrower rear portion between the side wall portions 17b and 17c. Side plate portions 17d and 17e are bent downward at substantially right angles from both side ends to face each other.

The flat plate portion 17a has three engaging pieces 17f which are notched at the center and bent downward (upward in FIG. 4).
An opening 17g having a rectangular shape elongated in the width direction at the tip side.
And are respectively formed. The side wall portions 17b and 17c
Pressing pieces 24 bent at substantially right angles are provided at respective front ends (obliquely upper left side in FIG. 4) of the front side, and lock claws 17h and 17i are provided at respective rear corners. A paper feed roller 22 is rotatably supported between the side wall portions 17b and 17c in the vicinity of each pressing piece 24.

As shown in FIG. 4, the side plate portions 17d, 1d
7e has an arc-shaped tip and a mounting hole 1
7m and 17n are formed to penetrate the tip side, respectively. Further, the one side plate portion 17d has a projection 17 formed by cutting off the arc-shaped tip of the outer peripheral edge and projecting a part thereof.
k.

The head mounting plate 25 is made of sheet metal, and is formed by bending a rectangular and horizontally long flat plate portion 25a and both ends in the longitudinal direction of the flat plate portion 25a on the opposite side to the side where the thermal head 26 is mounted. The bearing plate portions 25b and 25c and the other side opposite to the one side (obliquely upper left in FIG. 4) on which the thermal head 26 is disposed on the flat plate portion 25a are provided.
A rear wall (wall) 25d is formed by being bent in the same direction as b and 25c. The plate portion 25a has three holes 28 formed in parallel in the longitudinal direction thereof. The bearing portions 25b and 25c have bearing holes 25m and 25n formed therethrough. Also, the head mounting plate 2
5 has a bent base portion 25s on one of the bearing plate portions 25b.
Is provided, and the bent base portion 25s is used as a first rotation locking portion. The projection 17k engages with the bent base portion 25s in the first posture (see FIGS. 6A and 8) of the head mounting plate 25 with respect to the frame 17, and the coil spring 23 is inserted or detached at this position. To leave. A corner (filled portion in the figure) of the front end surface of the rear wall portion 25d is a second rotation locking portion 25t,
The projection 17k is engaged with the second rotation locking portion 25t in a state of elastic contact. The position of the second posture is a position where the head mounting plate 25 is mounted when the cover body 16 is in the most opened state with respect to the printer main body 12.

The thermal head 26 is formed by arranging a plurality of heating elements (not shown) in a strip shape. The thermal head 26 has a front end (one side) of the flat plate portion 25a of the head mounting plate 25 (the upper left side in FIG. 4). The bearing plate portions 25b and 25c and the rear wall portion 25d are attached and fixed to the surface of the flat plate portion 25a on the opposite side to the bent direction.

One end of each of the plurality of coil springs (biasing members) 23 is a protruding portion projecting outward in the elastic biasing direction, and the other ends thereof extend in a direction perpendicular to the elastic biasing direction. It has a flat ring shape. Then, the side plate portions 17d and 17e of the frame 17 and the head mounting plate 2
5, the bearing plate portions 25b and 25c are respectively arranged to face each other, and the mounting holes 17m and 17n, and the bearing holes 25m and 25n
Are overlapped and supported by a support shaft 18, and a plurality of coil springs 23
7 and the head mounting plate 25, the frame 17
The head mounting plate 25 is elastically urged against this. In addition, a C-shaped washer 19 for retaining is fitted in a notch formed in the outer peripheral wall of the support shaft 18.

As shown in FIG. 2, the support 27 is made of black resin, has a substantially inverted triangular cross section, and is provided on the inner side (the lower side in the figure) of the flat plate portion 17a of the frame 17. Is provided. At the vertex (lower end) of the support 27,
Two paper feed rollers 29 are rotatably supported.

A paper feed roller 22 is rotatably supported between the side walls 17b and 17c of the frame 17 near each pressing piece 24. The paper feed roller 22 is formed of a non-adhesive member to which an adhesive is unlikely to adhere, such as a coating material such as silicon or fluorine on the surface thereof, or a coating material containing a particulate material added thereto. The paper feed roller 22 elastically contacts the platen roller 35 and is driven by the rotation of the platen roller 35.

Next, a method of assembling the cover body 16 will be described with reference to FIGS. First, FIGS. 3 and 4
As shown in (1), the frame 17 is installed with its flat plate portion 17a inside facing upward. Next, a head mounting plate 25 having a thermal head 26 previously attached and fixed to the flat plate portion 25a with an adhesive (not shown) or the like is prepared. As shown in FIG. 5, the bearing plates 25b and 25c of the head mounting plate 25 are opposed to the side plates 17d and 17e of the frame 17, and the outer surface of the side plate 17d and the bearing plate 25
b with the inner side surface of the side plate abutting against the inner side surface.
7d, 17e mounting holes 17m, 17n, bearing plate 25
The support shaft 18 is inserted through the bearing holes 25m and 25n of the b and 25c from the bearing plate 25b side (the left side in FIG. 5). The insertion operation of the inserted support shaft 18 stops when the C-type washer 19 fitted on the outer peripheral wall of the support shaft 18 hits the bearing plate 25b. Thus, the head mounting plate 25 is rotatably supported by the frame 17 via the support shaft 18. And the projection 17k of the frame 17
When the head mounting plate 25 rotates about the support shaft 18 at a rotation angle of a predetermined angle or more, the head mounting plate 25 comes into contact with the bent root portion 25s in the first posture.
Not to be engaged with.

Next, as shown in FIGS. 7 and 8, the head mounting plate 25 is widely opened with respect to the frame 17, and the coil springs 23 are individually placed in the gaps between the frame 17 and the head mounting plate 25. , And the ring portion at one end of the coil spring 23 is fitted into each engagement piece 17f of the frame 17, and the projection at the other end of the coil spring 23 is inserted into each hole 28 of the head mounting plate 25 and locked. . by this,
The head mounting plate 25 is axially supported on the frame 17 in the first posture by the elastic biasing force of the coil spring 23, and abuts the bent base portion 25s with the projection 17k with a weak elastic biasing force. (See FIG. 6A).

Next, as shown in FIG. 6B, the head mounting plate 25 is moved against the frame 1 against the elastic biasing force of the coil spring 23.
7 is pressed against the flat plate portion 17a side, the head mounting plate 25
Corresponds to the support shaft 18 in the arrow direction shown (counterclockwise direction).
Rotate around the fulcrum. Then, the head mounting plate 25 is slid in the axial direction of the support shaft 18 at a position where the coil spring 23 is elastically pressed. That is, the sliding movement is performed by the frame 17 of the support shaft 18 and the head mounting plate 25.
In the opposite direction (the direction of the arrow S shown in the figure)
The head mounting plate 25 is slid along with the support shaft 18 by a predetermined distance (t). In a state where the coil spring 23 is not pressed against the frame 17, even when the head mounting plate 25 is moved in the axial direction of the support shaft 18, the end face of the rear wall portion 25d hits the side plate portion 17d and cannot be slid. ing.

6C and FIGS. 9 and 10
As shown in the figure, the second rotation locking portion 2 of the head mounting plate 25
5t is engaged with the projection 17k in the second posture. The rear wall portion 2 which is the second rotation locking portion 25t of the head mounting plate 25
5d is engaged with the projection 17k while maintaining a state of being strongly pressed against the elastic biasing force of the three coil springs 23.

Next, the cover body 16 assembled so far is
Is mounted and fixed inside the flat plate portion 17a of the frame 17, and further, the side walls 17b, 17
The paper feed roller 22 is mounted between the points c.

Next, the operation of such a thermal printer will be briefly described. First, a roll of label paper is inserted into the printer main body 12, and the cover 16 is closed. Here, the label paper is composed of a band-shaped backing sheet on which a label release layer is applied and formed on the front side, and a label having an adhesive layer on the back side temporarily attached to the front side of the backing sheet at a predetermined interval. . By closing the cover 16, the first and second lever arms 44 and 46 pressed against the cover 16 rotate. The lock claws 17h and 17i of the cover body 16 are connected to the first and second lever arms 4 respectively.
Locked to lock claw receiving portions 44b, 46b of 4, 46,
A detection switch (not shown) is pressed by the pressing piece 24 to detect the closed state and the locked state of the cover body. The gear group 5 is driven by the driving force of the stepping motor 54.
5 rotates to rotate the platen roller 35. By the thermal head 26 elastically contacting the platen roller 35, print recording is performed on the label of the label sheet sandwiched therebetween. The mounting paper of the label paper is turned in the paper feeding direction by the turning bar 31, and is sandwiched between the rotating platen roller 35 and the paper feeding roller 22 driven by the rotation of the platen roller 35,
Paper is fed in the discharge direction. On the other hand, the printed label is discharged to the outside through the opening 17g of the cover body 16.

Next, the effects of the cover 16 of the thermal printer described above will be described. 1) The cover body 16 of the thermal printer has a head 17 having a frame 17 having side plates 17d and 17e facing each other, and a thermal head 26 rotatably provided on the side plates 17d and 17e via a support shaft 18. Board 25
And a coil spring 23 which is engaged between the frame 17 and the head mounting plate 25 and elastically urges the head mounting plate 25 with respect to the frame 17. The head mounting plate 25 is provided with a protruding portion 17k to which the head mounting plate 25 can abut by movement. The head mounting plate 25 has a bent root portion (first rotation locking portion) 25s and a rear wall portion (second rotation locking portion).
25t) is provided, and the bent base portion 25s is brought into contact with the protrusion 17k to be in the first posture, and further from the first posture, while resisting the elastic urging force of the urging member. The head mounting plate 25 which is rotated by being pressed against the frame 17
Is moved to the second posture by sliding in the axial direction of the support shaft 18, and the rear wall 25d is engaged with the projection 17k in the second posture, so that the frame 17 and the The coil spring 23 can be inserted or removed in the first position in which the head mounting plate 25 is widely opened, so that a large-scale jig is not required, and assembling work and maintenance work can be easily performed. Can be. Further, in the second posture, the head mounting plate 2 with a predetermined elastic biasing force.
5 with the platen roller 35
And a desired print record can be made on the sandwiched sheet.

2) The projections 17k are provided on the side plates 17d and 17d.
The head mounting plate 25 is formed so as to cut out and project at least a portion of at least one of the side plates 17d (in the embodiment, the side plate portion 17d). The support shaft 18 faces the portions 17d and 17e.
And a thermal head 26 are arranged on one side of the head mounting plate 25 and the other edge is bent in the same direction as the bearing plate portions 25b and 25c. 25d, and the first rotation locking portion is formed by the bent base portion 25s of the bearing plate portion 25b, and the second rotation locking portion is formed by the rear rotation locking portion. The first and second walls are configured by the wall portion 25d.
17k for determining the posture of the head, and this projection 17k
The bent base portion 25s and the rear wall portion 25d that are engaged with the boss can be formed easily and with high precision by press working or the like.

3) The rear wall 25d is provided with a thermal head 26
The head mounting plate 25 attached to the frame 17 is formed in a belt-like shape by bending the edge of the head mounting plate 25 along the longitudinal direction of the frame 17. Even if the tip corner of the portion 25d is applied in addition to the left and right unequal elastic biasing force, the head mounting plate 25
Can be prevented from being deformed.

Although the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment.
Changes can be made without departing from the spirit of the invention.

[0033]

The cover body of the printer of the present invention described above has a frame having side plates facing each other and a print head rotatably provided on the side plates via a support shaft. The head mounting plate, comprising a biasing member that is engaged between the frame and the head mounting plate and elastically biases the head mounting plate with respect to the frame.
The head mounting plate is provided with a restricting portion that can be brought into contact with the head mounting plate by rotation of the head mounting plate, and the head mounting plate is provided with a rotation locking portion that restricts the rotation of the head mounting plate. Is rotated by being resiliently pressed toward the frame side against the elastic biasing force of the biasing member, and is slid in the axial direction of the support shaft so that the rotation locking portion engages with the regulating portion. This allows the biasing member to be smoothly inserted or removed in the first position in which the frame and the head mounting plate are widely opened, so that a large-scale jig is not required, and assembly and maintenance work is performed. And so on.

[Brief description of the drawings]

FIG. 1 is a schematic overall perspective view of a thermal printer according to an embodiment of the present invention with a cover body opened.

FIG. 2 is a perspective view of a cover body of the printer.

FIG. 3 is a perspective view of a main part of the cover body.

FIG. 4 is an exploded perspective view of a cover body in FIG.

FIG. 5 is an enlarged perspective view of a main part of a cover body in FIG. 3;

FIG. 6 is an explanatory diagram illustrating a method of assembling a cover body of the thermal printer according to the embodiment of the present invention.

FIG. 7 is a perspective view for explaining a state of a cover body in FIG. 6A.

FIG. 8 is a perspective view for explaining a state of a cover body in FIG. 6A.

FIG. 9 is a perspective view for explaining a state of a cover body in FIG. 6C.

FIG. 10 is a perspective view for explaining a state of a cover body in FIG. 6C.

[Explanation of symbols]

 Reference Signs List 16 cover body 17 frame 17d, 17e side plate part 17k regulating part (projection part) 18 support shaft 23 coil spring (biasing member) 25 head mounting plate 26 thermal head (print head) 25s first rotation locking part (folding) 25t 2nd rotation locking part 25d Rear wall part (wall part)

Claims (4)

[Claims] 1. A frame having side plates facing each other, a head mounting plate having a print head rotatably provided on the side plates via a support shaft, and between the frame and the head mounting plate. Locked to the
An urging member for elastically urging the head mounting plate with respect to the frame, wherein the frame is provided with a regulating portion that can be brought into contact with the head mounting plate by rotation of the head mounting plate; The head mounting plate is provided with a rotation locking portion for restricting the rotation of the head mounting plate, and the head mounting plate is pressed against the frame side while resisting the elastic biasing force of the biasing member. A cover body for a printer, wherein the cover is rotated and slid in the axial direction of the support shaft so that the rotation locking portion engages with the restricting portion. 2. A frame having side plates facing each other, a head mounting plate having a print head rotatably provided on the side plate via a support shaft, and between the frame and the head mounting plate. Locked to the
An urging member for elastically urging the head mounting plate with respect to the frame, wherein the frame is provided with a regulating portion that can be brought into contact with the head mounting plate by rotation of the head mounting plate; The head mounting plate is provided with first and second rotation locking portions for restricting the rotation of the head mounting plate. And the head mounting plate is rotated from the first posture by being resiliently pressed toward the frame while resisting the elastic urging force of the urging member, and is slid in the axial direction of the support shaft. The cover body of the printer is moved to a second posture by the operation, and the second rotation locking portion is engaged with the regulating portion in the second posture. 3. The restricting portion is formed by projecting at least a part of at least one of the side plate portions, and the head mounting plate is formed by bending both ends on a side where a longitudinal direction of the print head is located, and forming the side plate portion. A bearing plate portion formed so as to be able to support the support shaft in opposition to, the print head is arranged on one side of the head mounting plate,
A wall formed by bending an edge on the other side of the head mounting plate in the same direction as the bearing plate, wherein the first rotation locking portion is a bent base of the bearing plate. The cover body of the printer according to claim 2, wherein the second rotation locking portion is configured by the wall portion. 4. The cover body of the printer according to claim 3, wherein the wall portion is formed in a band shape by bending an edge portion of the head mounting plate along a longitudinal direction of the print head. .