JP2000289286A - Printer apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a printer apparatus which can simplify an assembly process and protects a print head. SOLUTION: The printer apparatus prints to a recording paper by pressing a thermal head 3 as a print head into contact with a platen 2 while moving the recording paper supplied to a printing position by the rotation of the platen 2. In the apparatus, a supporting shaft 12 as a supporting part is set to an end part of the thermal head 3, and a bearing 11 for axially supporting the supporting shaft 12 is set so that the thermal head 3 is rendered detachable to a direction nearly equal to an installation direction of the platen 2 and the thermal head 3 can rotate. A pressing member 14 is set to the bearing 11 for pressing the supporting shaft 12 to rotate the thermal head 3 away from the platen 2 at a non-printing time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a printer device having a platen and a head incorporated in a frame and printing on recording paper. More specifically, the present invention relates to a structure for incorporating a print head into a frame.

[0002]

2. Description of the Related Art A general configuration of a conventional printer will be briefly described. A conventional printer includes a thermal head 102 as a print head and a platen 101, as shown in FIG. The platen 101 is held rotatably about a shaft 101a along the width direction of the recording paper. Specifically, the axis 10 of the platen 101
1a includes a stepping motor 10 via a train wheel 103.
4 are connected. The rotational motion of the stepping motor 104 is reduced by the train wheel 103 and transmitted to the shaft 101a, and the platen 101 rotates intermittently in the direction of the arrow a for paper feeding.

[0005] The thermal head 102 is arranged to face the platen 101 with a recording sheet therebetween. The thermal head 102 is held so as to be rotatable about a shaft 105. When performing a printing operation, the thermal head 102
The second heating element is pressed against the recording paper. When the heating element is energized in this state, one line of characters is printed on the recording paper. When printing for one line is completed, the platen 101 rotates in the direction of arrow a to feed the recording paper.

A schematic sectional structure of the printer shown in FIG. 5A is represented as shown in FIG. The thermal head 102 is disposed to face the platen 101 with the recording paper 106 therebetween. Thermal head 102
Is another axis 105 parallel to the axis 101a of the platen 101.
When rotated counterclockwise around the center, the heating element located above the shaft 105 is pressed against the platen 101. A spring member 107 is interposed between the thermal head 102 and the frame 108 of the printer to apply this pressing force. On the other hand, when the thermal head 102 is rotated clockwise against the urging force of the spring member 107, the heating element of the thermal head 102 retreats from the platen 101.

Here, a specific configuration example of the printer device shown in FIG. 5 will be described with reference to a schematic side sectional view shown in FIG. The frame 108 has a substantially rectangular parallelepiped shape having upper, lower, left, and right surfaces. 6, the upper surface of the frame 108 is represented by U, the lower surface thereof is represented by D, and the right surface thereof is represented by R. Note that the left side L of the frame 108 is
It is located on the side opposite to the right surface R and is on the near side of the page and is not shown in FIG. The platen 101 is rotatably supported between a left surface L and a right surface R of the frame 108. The thermal head 102 is also pivotally supported between the left surface L and the right surface R of the frame 108, and rotates so as to be able to open and close with respect to the platen 101. Printing is performed on recording paper (not shown) supplied from the lower surface D side of the frame 108 between the platen 101 and the thermal head 102, and the upper surface U of the frame 108 is printed.
Discharge to the side.

[0006]

In the structure of the conventional printer shown in FIG. 6, both right and left sides L,
The thermal head 102 is supported by the support shaft 105 penetrating through the R
Of both ends 102a (only one end is shown in the figure)
I support. Therefore, in order to incorporate the thermal head 102, first, the support shaft 105
Alternatively, it is necessary to insert the component from the left side L and then attach a component for regulating the movement of the support shaft 105 in the thrust direction. Next, the thermal head 102 is assembled from, for example, the upper surface U, and both ends 102 a of the thermal head 102 are engaged with the support shaft 105.

As described above, in the conventional printer, there are two or three directions of assembling and disassembling the thermal head 102, and there is a problem that the assembling process is complicated. That is, in order to mount the support shaft 105 and engage the thermal head 102 with the support shaft 105, the frame 108
Has to be performed from the left side L or right side R and the upper surface U, or from the left and right sides L and R of the frame 108 and the upper surface U. Further, when removing the thermal head 102 for component replacement or the like, the support shaft 105 must be pulled out from the frame 108 in the thrust direction. Therefore, if there is a deceleration wheel train 103 or the like in the vicinity, it is necessary to remove them all.

There is a printer device designed to improve the assemblability of such a printer device. This printer is disclosed in Japanese Utility Model Laid-Open Publication No. 7-5745, and is configured as shown in FIG. In the thermal head 203 as a print head,
A heat sink 204 is provided. Projections 206 are formed below both ends of the heat sink 204 of the thermal head 203 in the longitudinal direction, and bushes 207 are fitted into the projections 206. The bush 207 has a D-shaped cross section in which one side of the outer periphery is cut off, and is fitted into the protruding piece 206 by press fitting.

A frame 201 of the printer body rotatably supports a platen 202. Lock holes 208 for fitting the bushes 207 of the thermal head 203 are formed on the lower surfaces of both ends of the frame 201. This locking hole 2
08 has an insertion groove 208a below and a hole 208b above the bush 207 having a diameter that allows the cross-sectional shape of the bush 207 to rotate. The width of the insertion groove 208a is
The bush 207 slides when the thermal head 203 is mounted on the frame 201, and the bush 207 is prevented from falling off when the mounted thermal head 203 is tilted to the platen 202 side.
Is smaller than the diameter of the D-shaped portion. This hole 208b
In order to make the printing surface of the thermal head 203 closely adhere to the outer periphery of the platen 202, the thermal head 203 is made slightly larger than the bush 207 so as to have a slight play to avoid being over-constrained.

The pressing member 205 presses the thermal head 203 held by the frame 201 toward the platen 202. A spring member 2 for pressing the thermal head 203 attached to the frame 201 is provided in front of the pressing component 205.
09 are attached, stopper portions 210 are formed at both ends of the pressing component 205, and holes 213 to be fitted into the positioning projections 212 of the frame 201 are formed in the holder 211 behind the pressing component 205. Here, the head-up lever 214 releases the pressing of the thermal head 203 toward the printing side, and the stopper 210 of the pressing component 205 slides into the receiving window 215.

When assembling the printer device shown in FIG.
No. 3 heat sink 204 is inserted.
7 and 207 are inserted into the insertion grooves 208 of the respective locking holes 208 and 208.
a, 208a and slides toward the upper surface, and the thermal head 203 is lowered to the platen 202 side in a state where the whole of the bushes 207, 207 enter the holes 208b, 208b. This allows the thermal head 203 to move the frame 2 without the bush 207 falling out of the locking hole 208.
01 is held.

As described above, in this conventional example, the platen 20
2 and the pressing component 205 are assembled into the frame from the upper surface side, and the thermal head 203 is assembled into the frame from the lower surface side. In general, when performing automatic assembly, the direction in which the components are incorporated is preferably as small as possible, and it is more preferable to incorporate the components from the upper surface side than from the lower surface side. However, in the conventional example shown in FIG. It has to be assembled from the lower surface side, so that it is necessary to add a reversing step of the frame 201 and the like, and there is a problem that handling becomes complicated.

Further, in such a configuration, the thermal head 203 is always in pressure contact with the platen 202 even during a period other than the printing operation, and the heating element formed on the thermal head 203 always contacts the platen 202. Therefore, it is not preferable for the heating element, and there is a problem that the life is reduced. SUMMARY OF THE INVENTION It is an object of the present invention to provide a printer device capable of simplifying an assembly process and protecting a print head.

[0014]

According to the present invention, a printer is provided with a support at an end of a print head so that the print head can be freely attached and detached in a direction substantially the same as the direction in which the platen is mounted. And a bearing for supporting the supporting portion. ADVANTAGE OF THE INVENTION According to this invention, a print head can be made detachable in the substantially same direction as the installation direction of a platen, and the assembly process of a printer apparatus can be simplified.

Further, the printer device is configured to pivotally support an end of the print head so that the print head rotates, and to rotate the print head so as to separate from the platen during a non-printing operation. Then, it is possible to prevent the printing head from being pressed against the platen during the non-printing operation, and to protect the printing head.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS According to the first aspect of the present invention, a printing head is pressed against the platen while rotating a recording paper supplied to a printing position by rotating a platen to print on the recording paper. In the printer device, a support portion is provided at an end of the print head, and the print head is supported in such a manner that the print head is detachably mounted in the same direction as the mounting direction of the platen so that the print head rotates. This is a printer device provided with bearings. The direction of assembling and disassembling the print head can be substantially the same as the direction of assembling the platen, so that the assembling process of the printer device can be simplified.

According to a second aspect of the present invention, there is provided a printer apparatus for printing on the recording paper by pressing a print head against the platen while moving the recording paper supplied to a printing position by rotating the platen. A printer device configured to pivotally support an end of the print head so that the print head rotates, and rotate the print head so that the print head separates from the platen during a non-printing operation. In addition, the problem that the life of the print head is shortened due to the print head being constantly in contact with the platen can be solved, and the print head can be protected.

According to a third aspect of the present invention, there is provided the bearing according to the first aspect, wherein the bearing is provided with a pressing member which presses the supporting portion so as to separate the print head from the platen during a non-printing operation. It is a printer device that can automatically separate the print head from the platen during non-printing operation,
The problem that the print head life is shortened by the print head being constantly in contact with the platen can be solved, the print head can be protected, and a complicated link for separating the print head from the platen during non-printing operation A mechanism or the like can be made unnecessary, and the number of parts of the printer device can be reduced.

According to a fourth aspect of the present invention, there is provided the printer device according to any one of the first to third aspects, wherein the print head is a thermal head. The direction can be substantially the same as the direction of mounting the platen, which simplifies the assembly process of the printer device and eliminates the problem that the life of the thermal head is reduced by the constant contact of the thermal head with the platen And the thermal head can be protected.

Hereinafter, a printer according to the present invention will be described based on specific embodiments. (Embodiment) A printer apparatus according to an embodiment of the present invention shown in FIG. 1 has a thermal head as a print head while moving a recording sheet supplied to a print position by rotating a platen 2 as in the conventional example. A printing apparatus for printing on the recording paper by pressing the head 3 against the platen 2, wherein a support shaft 12 as a support portion is provided at an end of the thermal head 3, and the thermal head 3 is substantially the same as the mounting direction of the platen 2. A bearing 11 is provided to support the support shaft 12 so that the thermal head 3 can be detachably mounted in the direction. The thermal head 3 is supported on the bearing 11 so that the thermal head 3 is rotated and separated from the platen 2 during a non-printing operation. The point that a pressing member 14 for pressing the shaft 12 is provided is different from the conventional example.

FIG. 1A shows a completed state of the printer device, and FIG. 1B shows an assembled / disassembled state of the printer device. The thermal head 3 is shown in FIG.
As shown in (b), a circuit board 6 made of ceramic or the like is mounted on a support 5 made of a metal plate or the like. On the circuit board 6, a heating element and a semiconductor element for driving the heating element are formed. Further, support shafts 12 are provided on both sides of an end of the thermal head 3 far from the circuit board 6.

Specifically, the support 5 of the thermal head 3
The support shaft 12 is formed at both ends 5a of the support shaft. The support shaft 12 is, for example, injection-molded into a D-cut shape in which a cross section thereof is obtained by cutting a part of the circumference, and is press-fitted into the protruding end 5 a of the support 5. This support shaft 1
2 is, for example, an injection molded article of polyacetal. However, the support shaft 12 is not limited to this, and the support shaft 12 may be formed integrally with the support 5 of the thermal head 3 by die casting or the like.

The frame 1 has an upper surface U, a lower surface D, a left surface L, and a right surface R (the right surface R is not shown because it is located on the side facing the left surface L and is on the near side of the paper). It has a housing structure for holding the head 3 and the like. The frame 1 has a pair of side walls formed along the left and right surfaces L and R, and has a base formed along the lower surface D and connecting both side walls to each other. Bearings 11 each having a notch 13a are integrally formed on the inside of the both side walls facing each other. FIG. 1B shows only the bearing 11 formed inside the side wall on the left side L side. The frame 1 and the bearing 11 are integrally formed, for example, by injection molding of a plastic material.

As shown in FIG. 2 (a), the bearing 11 has a notch 13a opened upward for inserting the support shaft 12 of the thermal head 3, and the support 11 with the thermal head 3 mounted. And a bearing portion 13b that pivotally supports the shaft 12. This notch 13
The width A of a is about the shortest diameter length of the cross section of the support shaft 12 in the D-cut shape so that the thermal head 3 can be inserted.

Further, the bearing 11 is provided with a pressing member 14 for pressing the support shaft 12 so as to rotate the thermal head 3 and separate from the platen 2 during a non-printing operation. The pressing member 14 includes, for example, a pressing spring 15, a pressing force adjusting slide 16, and an adjusting screw 17. The specific configuration of the pressing member 14 will be described later.

Here, the configuration of the printer will be described more specifically. This printer is shown in FIG.
As shown in (a), basically, the frame 1 and the platen 2
And a thermal head 3. The platen 2 is rotatably supported between a left surface L and a right surface R of the frame 1. Similarly, the thermal head 3 is pivotally supported between the left surface L and the right surface R of the frame 1, and rotates so as to be able to open and close with respect to the platen 2. With this structure, printing is performed on the recording paper (not shown) supplied from the lower surface D of the frame 1 between the platen 2 and the thermal head 3,
Is discharged to the upper surface U side.

In FIG. 1A, the recording paper supply port formed on the lower surface D of the frame 1 is represented by IN1.
The outlet located on the upper surface U side is denoted by OUT.
The supply path from IN1 to OUT is called a straight path. In this case, in order to prevent the recording paper from coming into contact with the circuit element mounted on the thermal head 3, the protection sheet 4
Are interposed between the platen 2 and the thermal head 3. In some cases, the recording paper may be inserted from another supply port IN2 opened on the rear surface of the frame 1 and taken out from the discharge port OUT on the upper surface U side. The supply path from IN2 to OUT is called a curl path.

The thermal head 3 is pressed against the platen 2 by a leaf spring member 7. At the time of printing operation, the pressing cam 8 presses the leaf spring member 7 to further apply a pressing force. Further, the frame 1 incorporates a stepping motor 9 for feeding paper. The stepping motor 9 is connected to the platen 2 via a reduction gear train (not shown), and drives the platen 2 to rotate. The platen 2 feeds the recording paper inserted from IN1 or IN2 as it rotates.

The recording paper supplied to the frame 1 is
It is detected by the paper sensor 10. In FIG. 1, the paper sensor 10 monitors a straight path on the IN1 side. Here, the assembling / disassembling operation of the printer device will be described with reference to FIGS.

As shown in FIG. 1B, the thermal head 3 is dropped vertically from the opening in the upper surface U of the frame 1 toward the lower surface D, and as shown in FIG. The support shafts 12 at both ends of the thermal head 3 are dropped so as to engage with the bearings 11 of the frame 1, and as shown in FIG. 2B, the support shafts 12 at both ends of the thermal head 3 correspond to the support shafts 12 through cutouts 13a. Engage with bearing 11. After engaging the thermal head 3 with the bearing 11 in this manner, as shown in FIG. 2C, the circuit board 6 side of the thermal head 3 is tilted toward the platen 2 to The pressure comb 8 and the like are mounted above the thermal head 3. In addition, the platen 2, the leaf spring member 7 and the pressure comb 8
These are mounted at respective mounting positions from the opening on the upper surface U of the frame 1 toward the lower surface D.

As described above, the thermal head 3 is configured as shown in FIG.
As shown in (b), the thermal head 3 can be attached to and detached from the frame 1 only when it is held in the vertical state. By simply rotating the thermal head 3 beyond a certain angle from the above vertical state, the thermal head 3 is irremovably rotated from the bearing 11 about the two support shafts 12 and is supported to open and close with respect to the platen 2. . Therefore, the direction of assembly and disassembly of the thermal head 3 can be limited to one direction from the upper surface U of the frame 1.

Here, a specific configuration of the pressing member 14 provided on the bearing 11 will be described. FIG.
As shown in FIG. 2B, the thermal head 3 dropped into the bearing 11 in a vertical direction from the upper surface U of the frame 1 is shown in FIG.
As shown in (c), the support shaft 1 of the thermal head 3
A pressing spring 15 such as a leaf spring is attached to the bearing portion 13b of the bearing 11 formed inside the both side walls of the frame 1 so that the pressing force to the flat portion 12a having the D-cut cross section increases in the direction. Is incorporated. This pressing spring 15
When the thermal head 3 is not engaged, FIG.
Pressing force adjusting slide 16 and adjusting screw 1
7, the position is adjusted so as to protrude toward the bearing surface of the bearing portion 13b.

As shown in FIG. 3, the projecting amount of the pressing spring 15 is determined by the flat portion 12a of the support shaft 12 of the thermal head 3.
The pressure is adjusted to an appropriate value so as to balance the pressing force P by the pressing member 14 for pressing the pressure and the pressing force F of the leaf spring member 7 for pressing the thermal head 3 against the platen 2.
When the weight of the thermal head 3 is W, the balance between the pressing force P of the pressing spring 15 and the pressing force F of the leaf spring member 7 is represented by the following (Equation 1). The projection amount of the pressing spring 15 is set so as to satisfy (Equation 1).

P × L3> F × L1 + W × L2 (Equation 1) where L1 is the distance from the center of the bearing 11 to the point where the pressing force F of the leaf spring member 7 acts, and L2 is the bearing 11 The distance from the center to the center of gravity of the thermal head 3 and L3 is the distance from the center of the bearing 11 to the point where the pressing force P of the pressing spring 15 acts. As described above, the thermal head 3 includes the pressing spring 1.
5 and the leaf spring member 7, respectively, but at the time of print recording for printing on a recording paper (operation for forming an image on the recording paper), the pressure cam 8 rotates about its rotation axis. The plate spring member 7 is pressed, and the pressing force of the pressing cam 8 is further applied to the pressing force F of the plate spring member 7 to press the thermal head 3 against the platen 2. After the end of the printing operation (during the non-printing operation), as shown in FIG.
The pressing cam 8 rotates in the opposite direction to release the pressing force from the pressing cam 8, and the pressing spring 15 of the bearing 11 is released.
The thermal head 3 is driven by the platen 2
Separated from That is, the thermal head 3 is rotated in a direction away from the platen 2 by the pressing spring 15 of the bearing 11, is separated from the platen 2 to a position of the distance δ, and becomes a stationary state, and maintains this stationary state until the next printing operation. It will be.

With this configuration, the thermal head 3 can be assembled and disassembled only in one direction from the upper surface U of the frame 1. The one direction from the upper surface U is the same as the direction in which the platen 2 is mounted. Since the directions are substantially the same, the assembly process of the printer device can be simplified. In addition, by incorporating a pressing member 14 that presses the support shaft 12 of the thermal head 3 so as to separate the thermal head 3 from the platen 2 during a non-printing operation, the bearing 11 that supports the support shaft 12 of the thermal head 3 is installed. During operation, the thermal head 3 can be automatically separated from the platen 2, and the problem that the life of the thermal head 3 is shortened due to the thermal head 3 always contacting the platen 2 can be solved. It is possible to protect the thermal head 3 from the platen 2 during the non-printing operation, thereby eliminating the need for a link mechanism and the like, thereby reducing the number of components of the printer device.

In this embodiment, the support shaft 12 of the thermal head 3 is pressed by the pressing member 14 to
Is separated from the platen 2. However, even when the thermal head 3 is pulled by a spring member or the like from the leaf spring member 7 side of the thermal head 3 so as to separate the thermal head 3 from the platen 2, the same applies. Has an effect. In this embodiment, the print head is a thermal head. However, similar effects can be obtained even when the print head is an inkjet head or the like other than the thermal head.

[0037]

As described above, according to the printer device of the first aspect of the present invention, the support portion is provided at the end of the print head, and the print head is detachable in the substantially same direction as the mounting direction of the platen. By providing a bearing that supports the support portion so that the print head rotates, the direction of assembly and disassembly of the print head can be made substantially the same as the direction of assembling the platen. The assembling process can be simplified.

According to the printer device of the present invention, the end of the print head is pivotally supported so that the print head rotates, and the print head separates from the platen during a non-printing operation. By thus rotating the print head, it is possible to solve the problem that the life of the print head is reduced due to the print head being constantly in contact with the platen, and the print head can be protected.

According to the printer device of the third aspect of the present invention, the support portion is provided on the bearing of the first aspect so that the print head is rotated to separate from the platen during a non-printing operation. By providing a pressing member for pressing, the print head can be automatically separated from the platen during a non-printing operation, and the problem that the life of the print head is reduced due to the print head being constantly in contact with the platen is solved. Thus, the print head can be protected, a complicated link mechanism for separating the print head from the platen during a non-printing operation can be dispensed with, and the number of parts of the printer device can be reduced.

According to a fourth aspect of the present invention, the print head of the printer according to any one of the first to third aspects is a thermal head, thereby assembling the thermal head. -The direction of disassembly can be made almost the same as the direction of mounting the platen,
The printer device assembly process can be simplified,
The problem that the life of the thermal head is shortened due to the thermal head being constantly in contact with the platen can be solved, and the thermal head can be protected.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a configuration of a main part of a printer device according to an embodiment of the present invention.

FIG. 2 is an exemplary sectional view showing an assembled state of the printer device according to the embodiment;

FIG. 3 is a sectional view showing the relationship between the pressing force applied to the thermal head of the embodiment.

FIG. 4 is a sectional view showing a printing standby state of the printer according to the embodiment;

FIG. 5 is a schematic diagram showing a general configuration of a conventional printer device.

FIG. 6 is a cross-sectional view showing a specific configuration of a conventional printer device.

FIG. 7 is an exploded perspective view showing another conventional printer device different from the printer device shown in FIG. 6;

[Explanation of symbols]

 Reference Signs List 1 frame 2 platen 3 thermal head 11 bearing 12 support shaft 12a bearing flat portion 13a notch 13b bearing portion 14 pressing member 15 pressing spring 16 pressing force adjusting slide 17 adjusting screw

Claims (4)

[Claims] 1. A printing apparatus for printing on a recording sheet by pressing a printing head against the platen while rotating a recording sheet supplied to a printing position by rotating a platen, wherein a supporting portion is provided at an end of the printing head. And a bearing for supporting the support portion so that the print head is detachably mounted in a direction substantially the same as the mounting direction of the platen and the print head is rotated. 2. A printing apparatus for printing on said recording paper by pressing a printing head against said platen while rotating a recording paper supplied to a printing position by rotation of a platen, wherein said printing head is rotated. A printer device configured to pivotally support an end of the print head and rotate the print head so that the print head is separated from the platen during a non-printing operation. 3. The printer device according to claim 1, wherein the bearing is provided with a pressing member for rotating the print head during a non-printing operation and pressing the supporting portion away from the platen. 4. The printer according to claim 1, wherein the print head is a thermal head.