JPH03270963A - Thermal recorder - Google Patents

Abstract

PURPOSE:To make it possible to detach an unused head from a platen roller by providing head lifting means to be displaced at every head support means in positions on the platen roller where selected one head support means or two or more adjacent head support means are to be attached with pressure and detached. CONSTITUTION:When a dial 17 is rotated to set an index to OFF and a rotational angle of a head pressure shaft 16 is made to be zero base, head pressing plates 38, 55, 55' face eccentric narrow parts b of cam faces B, A, C so that thermal heads 44, 66, 67 go up. When the pressure shaft 16 is rotated from this state by 90 deg. and the index of the dial 17 is set to A3.A4, only the thermal head 66 is attached with pressure to the platen roller 14 and other thermal heads 44, 67 go up with respect to the platen roller 14. Selecting state of up and down of the thermal heads 66, 44, 67 is recorded on a recording paper with the size A3 or A4, which is made to correspond to the breadth of the selected recording paper in case it is to be cut.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a thermal recording device such as a thermal recording device and a thermal transfer recording device, and particularly to a thermal recording device suitable for recording large-sized recording paper.

[Conventional technology]

Conventionally, automatic drawing machines that draw on large recording paper such as AO or Al size, along with so-called pen plotters, have used array structures for their high speed of drawing, low noise, and ease of maintenance. A thermal recording device using an in-line type thermal head is used. In this type of thermal recording device, it is difficult to put into practical use a long thermal head compatible with AO and Al sizes, considering the manufacturing yield, manufacturing cost, maintainability, etc. A plurality of popular products such as A3 size heads are connected in the line direction to record large areas. In this case, during recording, all heads were brought into contact with the platen roller regardless of the size of the recording paper used.

[Problem that the invention seeks to solve]

Depending on the size of the recording paper, even when the head is not in use, during recording, the head comes into direct contact with the platen roller, ie, without the recording paper intervening, and the friction between the two causes deterioration of the head. Furthermore, the above-mentioned friction increases the mechanical load and the electric power required to drive the platen roller becomes larger than necessary.

The present invention aims to eliminate the above-mentioned defects.

[Means to solve problems]

In order to achieve the above object, the present invention provides a plurality of thermal heads disposed at shifted positions in a line direction, a platen roller facing these thermal heads, and a plurality of thermal heads arranged with respect to the platen roller. Head support means movably supported in the crimping and separating directions, and a thermal head in which the selected head support means supports a selected one of these head support means or selected two or more adjacent in the line direction. The apparatus is provided with head elevating means provided for each of the head supporting means to be displaced, at two positions, a position where the head is pressed against the platen roller and a position where the head is separated from the platen roller.

[Effect]

In the above configuration, if a desired head support means is selected according to the size of the recording paper and the selected desired head support means is moved by driving the head elevating means in the head down direction, the head support means can be moved. A thermal head supported by means presses against the platen roller. The thermal heads are arranged over the entire length of the recording paper in the width direction in contact with the platen roller, and the thermal heads that are not selected are kept separated from the platen roller. By driving a desired head elevating means in the head-up direction, a desired thermal head can be elevated from the platen roller.

〔Example〕

The structure of the present invention will be described in detail below with reference to embodiments shown in the accompanying drawings.

In FIG. 2, a case body 2 houses a recording mechanism therein, and side walls 4a on both sides thereof.

A top cover 6 is attached to the upper end of 4b so as to be openable and closable. Inside the case body 2, on the front side,
For example, a continuous recording paper 8 made of thermal paper having a width that allows production of A1 size standard paper by cutting after recording is wound into a roll in a holder 10 and stored therein. A feed roller 12 is arranged on the back side of the continuous recording paper 8. A guide (not shown) extending in the horizontal direction is attached to the further back side of the feed roller 12, and a platen roller 14
and the head pressurizing shaft 16 are arranged parallel to each other.

Above the platen roller 14, a feed roller 18,
20, and a guide, a feed roller, a loop cutter, etc. (not shown) are arranged in the recording paper conveyance path between the feed rollers 18, 20 and the platen roller 14. A paper detection sensor (not shown) is disposed in the recording paper conveyance path, and a paper detection sensor (not shown) is arranged in the recording paper conveyance path downstream of the feed roller 18° 20.
is located. the feed rollers 12, 18, 20;
The platen roller 14 and the head pressure shaft 16 are connected to the side plate 28.
, 30. The head pressure shaft 16
As shown in FIG.
a, 32b, 54a, 54b,! 54a', 54b'
It is rotatably inserted into the side hole of the A head support shaft 34 is installed between the head pedestals 32a and 32b of the head support means 50, and the head support body 3 is mounted on the head support shaft 34.
6 and head pressing plate 38 are rotatably supported.

The intermediate portion of the head pressing plate 38 faces the cam surface B (see FIG. 9) forming portion of the head pressing shaft 16. This cam surface B has an eccentric enlarged portion a and an eccentric narrowed portion a.

A thermal head 44 is fixed to the head support 36. A head pressure spring 46 is attached between the other end of the head pressing plate 38 and the vicinity of the other end of the head support 36 . The head pressing plate 38 is provided with a spring pressure adjusting means so as to be able to adjust the strength of the elastic force of the head pressing spring 46. As shown in FIG. 11, the spring pressure adjustment means of the head support means 50 has a threaded portion of a pressure adjustment screw 48 screwed into a screw hole formed in the head pressing plate 38. The tip of the pressure adjusting screw 48 is in contact with the upper surface of a cylindrical spring pressing member 72 that is slidably fitted into a cylindrical guide hole formed in the head pressing plate 38. A head pressure spring 46 made of a coil spring is compressed and disposed between the spring placement hole formed in the head support 36 and the spring pressing member 72. Head pressure spring 4
6 can be adjusted by rotating the pressure adjustment screw 48, and the degree of adjustment is determined by the index provided on the head of the screw 48 and the scale 74 provided on the top surface of the head pushing member 38. It is configured to be displayed by the numerical value of. The spring pressure adjustment means of the head support means 52 and 53 also have substantially the same structure as described above. Head support means 52
In this case, the elastic force of the head pressure spring 62 can be adjusted by rotating the pressure adjustment screw 49. 91 is the head pressing plate 3
The lower surface of the head support 36 faces the locking surface of the locking metal fitting 91, and the locking metal fitting 91 prevents the opening of the head pressing plate 38 and the head support 36. The angle is regulated. The head pedestal 32
a, 32b, head support 36 and head pushing plate 3
8 constitutes a first head support means 5o, and a second head support means 52 having substantially the same principle as this head support means 50.
and the third head support means 53 are connected to the head pressurizing shaft 1.
6. Said second head support means 52
head pedestals 54a, 54b, head pressing plate 55,
The head support 56, the head support shaft 60, and the head pressure spring 62 are connected to the head pedestals 32a, 32b, the head pressing plate 38, the head support 36, the head support shaft 34, and the head pressure spring 62, respectively, of the first head support means 5o. It corresponds to the pressure spring 46. The head pressing spring 62 is arranged between the head pressing plate 55 and the head support 56. The head pressing shaft 16 facing the head pressing plate 55
As shown in FIG. 9, a cam surface A is formed on the surface. This cam surface A has an eccentric enlarged portion a and an eccentric narrowed portion a. A thermal head 66 is fixed to the head support 56 . The head pressing plate 55
With the head support shaft 60 as a reference, the end of the head pressure spring 62 on the opposite side is attached to the head pressure shaft 1.
It faces the cam surface A forming portion of No. 6. The head support means 53 has the same structure as the head support means 52, and its head pressing plate 55' faces the cam surface C of the head pressurizing shaft 16. As shown in FIG. 8, this cam surface C has an eccentric enlarged part a and an eccentric pinched part A. Head support body 5 of the head support means 53
A thermal head 67 is fixedly installed at 6'. The thermal head 44 is arranged such that its main surface forms an approximately 9o'' angle with respect to the thermal head 66.66.The heating resistors of the thermal head 44, 66.67 are arranged in the line direction. A drive motor 68 is disposed between the side wall 4a and the side plate 28 so as to be continuous with each other in the horizontal direction.
is provided, and the driving force of this motor 68 is configured to be transmitted to the platen roller 4. A paper size selection dial 17 is fixed to one end of the pressure work 6, as shown in FIG. As shown in FIG. 10, the side plate 28 has a zero reference angle (OFF position) of the pressure shaft 16 by interaction with the indicator on the dial 17.
And A3. A4 paper size selection angle position and Al, A2
A display indicating the paper size selection angular position and the AO paper size selection angular position is formed. the feed roller 18,
20 is driven by a paper ejection motor (not shown). The motor 68 and the paper ejection motor are configured to be controlled by a control circuit 82 consisting of a microcomputer. Head support means 5
0, a return spring 93 is provided between the head rear plate 92 fixed to the pedestals 32a, 32b and the head pressing plate 38 for biasing the head pressing plate 38 in a direction to bring the head pressing plate 38 into close contact with the head pressing shaft 16. It is being The head pressing plates 55, 55' of the head supporting means 52, 53 are in close contact with the head pressing shaft 16 due to their own weight.

Next, the operation of this embodiment will be explained.

When the eccentric enlarged portions a of the cam surfaces B, A, and C face the corresponding head pressing roots 38, 55.55', the head pressing plates 38, 55.55' The head pressure spring 4 receives pressure from part a.
6, 62, 62' via the head supports 36, 56.
56' is pressed in the direction of the platen roller 14, and the thermal head 44, 6667 is pressed against the platen roller 14. The head pressure work 6 is rotated, and the cam surfaces B, A, and C
The eccentric pinching part is the corresponding head pressing plate 38°5
5.55', the head pressing plate 38.5
5.55', the pressing force from the curved surface of the head pressing shaft 16 is released by the eccentric pinching parts of the cam surfaces B, A, and C. When this pressing force is released, the head pressing plate 38 of the head support means 50 moves around the head support shaft 34.
The head pressing plates 55, 55 of the 6-head support means 52 and 53 are swung by a predetermined angle in the direction in which the thermal head 44 moves away from the platen roller 14 (head upward direction) by the rotational force generated by the tensile force of a return spring (not shown). 'teeth,
The thermal head 66.6 swings at a predetermined angle due to gravity.
7 is configured to be separated from and opposite to the platen roller 14 by a predetermined distance. In this embodiment, the rising of the thermal head refers to the movement of the thermal head in the direction away from the platen roller, and the lowering of the thermal head refers to the movement of the thermal head in the direction of pressing against the platen roller.

When the dial 17 is rotated to set the indicator to display OFF and the rotation angle of the head pressurizing shaft 16 is set as a zero reference, the head pressing plates 38, 55 are rotated as shown in FIG.
．． 55' are cam surfaces B and A.

Facing the eccentric pinching part of C, all the thermal beds 44
, 66.67 is in a rising state. From this state, rotate the pressure shaft 16 90 degrees and set the index on the dial 17 to A3/A4.
As shown in FIG. 8, the thermal head 6
Only the thermal heads 44, 67 are pressed against the platen roller 14, and the other thermal heads 44, 67 are raised relative to the platen roller 14. The up/down selection state of the thermal head 66, 44, 67 is the selected recording paper 8 when recording on the recording paper 8 in A3 or A4 size and cutting it.
It corresponds to the width of When the pressure shaft 16 is rotated 180 degrees from the zero reference angle OFF as shown in FIG. 9 This state is in a state where it has increased relative to A1.
Or, it corresponds to the recording paper 8 selected for A2 size recording. When the pressure shaft 16 is rotated 270 degrees from the zero reference angle OFF as shown in FIG. It corresponds to the selected recording paper 8.

The operator sets the rotation angle of the pressure shaft 16 corresponding to the paper width based on the display on the display section located around the dial 17 and provided on the side plate 28.

The operator turns on the main switch and inserts the recording paper 8 between the head 66, 44, 67 and the platen roller 14. When this recording paper is inserted, the thermal head 66.44
．． 67 are all set in a raised state with respect to the platen roller 14. Next, the operator operates the dial 17 to lower the thermal head corresponding to the paper width of the paper 8, for example, 66°44.67, and press them onto the platen roller 4. Next, turn on the start switch. The control circuit drives the output shaft of the motor 68 in normal rotation,
While feeding the recording paper 8 in a predetermined direction, the selected thermal head 66, 64, or 67 is driven to create an image. - When the frame drawing is completed, the control circuit 82 transports the recording paper 8 by a predetermined amount, and then drives the loop cutter to cut the recording paper 8 according to the set paper size.

1. When carrying out the present invention, the structure of the head pressure shaft 16 and its cam surfaces A, B, and C is not particularly limited to the structure shown in the drawings, and a structure in which a cam plate is fixed to the head pressure shaft may be used. Also, head pressure shaft 16 and cam surfaces A, B, and C.
Alternatively, the structure of the cam plate is the head supporting means 50, 52.
．． The thermal heads 44, 66 . . 53 which they support.
67 constitutes a head elevating means for displacing the head to two positions: a position in which it is pressed against the platen roller 14 and a position in which it is separated from the platen roller 14. Further, the present invention is applicable not only to a thermal recording device that uses thermal paper, but also to a thermal transfer recording device that uses heat-melting ink, heat-sublimating ink, and the like.

〔effect〕

As described above, the present invention can move unused heads away from the platen roller, thereby reducing deterioration of the used heads and reducing power consumption required to drive the platen roller. Exists.

[Brief explanation of drawings]

Figure 1 is an external view, Figure 2 is an external view, Figure 3 is an external view, Figure 4 is a side view, Figure 5 is a side view, Figure 6 is a side view, Figure 7 is a side view.
The figure is a side view, Figure 8 is an explanatory diagram, Figure 9 is an external view, Figure 10 is
The figure is a side view, no. Figure J is a side view, and Figure 12 is a side view. 2...Case body, 4a, 4b...Side wall, 6...
Top cover, 8... Recording paper, 10... Holder, 12
...Feed roller, 14...Platen roller, 16.
...Head pressure shaft, 18.20...Feed roller, 22
, 24, 26...Sensor, 28, 30-...Side plate, 3
2a, 32b...Head pedestal, 34...Head support shaft, 36...Head support, 38...Head pressing plate, 44...Thermal head, 46...Head pressure spring, 48 ...Spring pressure adjustment means, 50, 52, 53.
...Head support means, 54a, 54b-head pedestal, 5
6.56'-head support, 60...head support shaft, 6
2... Head pressure spring, 66.67... Thermal head, 68... Drive motor.

Claims (1)

[Claims] (1) A plurality of thermal heads arranged at shifted positions in the line direction, a platen roller facing these thermal heads, and each of the thermal heads movable in the direction of pressing against and separating from the platen roller. a position where a thermal head supported by the selected head support means is pressed against the platen roller; A thermal recording apparatus characterized by comprising: head elevating means provided for each of the head supporting means to be displaced at two positions separated from each other.