JPH03270964A - Thermal recorder - Google Patents

Abstract

PURPOSE:To make it possible to automatically lift a thermal head dependent on the width of a recording paper by providing a control circuit which controls a first clutch, a second clutch and a drive motor, and selects a thermal head corresponding to the size of the paper so as to attach it with pressure to a platen roller. CONSTITUTION:A control circuit turns on a clutch 70, turns off a clutch 78, detaches a motor device from a drive motor 68, and couples the drive motor 68 with cam means 16. The control circuit selects head support means 50, 52, 53 corresponding to the size of a recording paper, drives the the drive motor 68 to drive the car means 16 for a predetermined quantity, changes the position of the head support means to one position of two positions, and makes selected thermal heads 44, 66, 67 contact tightly to a platen roller 14. Also, when the control circuit drives the cam means 16 in a direction that the selected thermal heads 44, 66, 67 are driven in the head up direction, the selected thermal heads 44, 66, 67 go up from the platen roller 14.

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 different positions in the line direction, a platen roller facing these thermal heads, and a plurality of thermal heads arranged with respect to the platen roller. A head support means that supports movably in the crimping and separating directions, and a thermal head that supports a selected one of these support means or selected two or more adjacent in the line direction are attached to the platen. A cam means for displacing the roller to two positions, a position where it is pressed against the roller and a position where it is separated from the roller, a power transmission mechanism that connects the cam means and an output shaft of a drive motor, and a first clutch provided in the power transmission mechanism. , a second clutch disposed between the output shaft of the drive motor and a device interlocked with the output shaft, and controlling the clutch and the drive motor to select a thermal head according to the paper size. and a control circuit for pressing the platen roller against the platen roller.

[Effect]

The control circuit turns on the first clutch and turns off the second clutch, disconnecting the motor equipment from the drive motor and coupling the drive motor with the cam means. The control circuit selects the head support means corresponding to the size of the recording paper, drives the drive motor to drive the cam means by a predetermined amount, changes the head support means to one of two positions, and adjusts the selected thermal Bring the head into close contact with the platen roller. These 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. The control circuit causes the cam means to
If the selected thermal head is driven in the head-up direction, the selected thermal head will rise 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 22 is provided on the recording paper conveyance path.
．． 24 (see FIG. 7) are arranged, and the feed roller 1
A paper detection sensor 26 (see FIG. 7) is disposed on the recording paper conveyance path downstream of the recording paper sheets 8 and 20. The feed rollers 12, 18, 20, platen roller 14, and head pressing shaft 16 are supported by side plates 28 and 30.

As shown in FIG. 3, the head pressurizing shaft 16 is connected to head support means 50, 52, .
53 head pedestals 32a, 32b, 54a, 54b.

It is rotatably inserted into the side holes 54a' and 54b'. a head pedestal 32a of the head support means 50;
A head support shaft 34 is installed between the head support shafts 32b, and one of the head support body 36 and the head pressing plate 38 is rotatably supported on the head support shaft 34. An intermediate portion of the head pressing plate 38 faces a portion forming a cam surface B (see FIG. 4) 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 . A spring pressure adjustment means 48 is provided on the head pressing plate 38, and the head pressing spring 4
The strength of the elastic force of 6 can be adjusted.

Reference numeral 91 denotes a locking metal fitting fixed to the head pressing plate 38, the locking surface of which faces the lower surface of the head support 36, and the locking metal fitting 91 allows the head pressing plate 38 and the head to be connected to each other. The opening angle with respect to the support body 36 is regulated. The head pedestal 32a.

32b, the head support 36, and the head pressing plate 38 constitute a first head support means 50, and a second head support means 52 and a third head support means 53, which have substantially the same principle as this head support means 50, constitute a first head support means 50. is installed on the head pressurizing shaft 16. a head pedestal 54a of the second head support means 52;

54b The head pressing plate 55, the head support 56, the head support shaft 60, and the head pressure spring 62 are respectively connected to the head pedestals 32a, 32b of the first head support means 50,
It corresponds to the head pressing plate 38, the head support body 36, the head support shaft 34, and the head pressure spring 46. The head pressing spring 62 is arranged between the head pressing plate 55 and the head support 56. As shown in FIG. 4, the cam surface A is formed on the surface of the head pressing shaft 16 that the head pressing plate 55 faces.

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 end of the head pressing plate 55 on the opposite side to the mounting side of the head pressure spring 62 with respect to the head support shaft 60 faces the cam surface A forming portion of the head pressure shaft 16. ing. The head supporting means 53 has the same structure as the head supporting means 52, and the head pressing plate 55' is connected to the head pressing shaft 1.
It faces the cam surface C of No.6. As shown in FIG. 5, this cam surface C has an eccentric enlarged portion a and an eccentric narrowed portion a. A thermal head 67 is fixed to the head support body 56' of the head support means 53. The thermal head 44 is arranged such that its principal surface forms an approximately 90'' angle with respect to the thermal heads 66 and 66.

The heating resistors of the thermal heads 44, 66, and 67 are arranged so as to be continuous in the line direction, with some parts overlapping in the horizontal direction. As shown in FIG. 1, a drive motor 68 is provided between the side wall 4a and the side plate 28, and the drive force of this motor 68 is transmitted to the platen roller 14 via a clutch 70. has been done. Further, the driving force of the motor 68 is applied to the belt pulley 72. Timing belt 74, belt pulley 76 and clutch 7
8 to the head pressurizing shaft 16. A positioning plate 94 is fixed to the pressure shaft 16, and a slit is formed at the origin angle position [P] of the positioning plate 94. Reference numeral 96 denotes a sensor, which is arranged opposite to the positioning plate 94 so as to be able to detect the slit.

The feed rollers 18, 20 are driven by a single paper ejection motor 80 (see FIG. 7). The motor 68, the paper ejection motor 80, and the clutch 70.
78 is configured to be controlled by a control circuit 82 consisting of a microcomputer, and the input section of the control circuit 82 includes the sensors 22, 24, 26, 96 and the platen roller 14 of the thermal head 44, 66, 67. A sensor 84 provided for each head is connected to detect the crimping state, that is, the head down state. In the head support means 50, a return spring 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. (not shown) is provided. Head pressing plate 55 of head support means 52 and 53
．． 55' is in close contact with the head pressurizing shaft 16 due to its own weight.

Next, the operation of this embodiment will be explained.

Eccentric enlarged portion a of the cam surfaces B, A, and C of the head pressurizing shaft 16
When the head pressing plate 38, 55.55' faces the corresponding head pressing plate 38, 55.55', the head pressing plate 38, 55.55' receives a pressing force from the eccentric enlarged portion a of the cam surface of the head pressing shaft 16, and the head pressing plate 38, 55.55' The head support 36.56.56' is pressed in the direction of the platen roller 14 via the thermal head 44.6667 against the platen roller 14. The head pressure shaft 16 is rotated,
When the eccentric pinching parts of the cam surfaces B, A, and C face the corresponding head pressing plates 38, 55, and 55', the head pressing plates 38, 55, and 55' The pinching portion releases the pressing force from the surface of the head pressing shaft 16. When this pressing force is released, the head pressing plate 38 of the head support means 50 is pressed against the head support shaft 3.
4 as the center, the thermal head 44 swings by a predetermined angle in the direction away from the platen roller 14 (head upward movement direction) by the rotational force caused by the tensile force of a return spring (not shown). The head pressing plates 55, 55' of the head support means 52, 53 are configured to swing by a predetermined angle due to gravity, so that the thermal heads 66, 67 are separated from and opposed to the platen roller 14 for 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. If the rotation angle of the pressurizing shaft 16 when the point P of the positioning plate 94 faces the sensor 96 is taken as a zero reference, then as shown in FIG. 5, when the pressurizing shaft 16 is at zero degree (OFF), the head Pressing plate 38.55.
55' faces the eccentric pinching parts of the cam surfaces B, A, and C;
All thermal heads 44, 66, 67 are in the raised state.

When the pressure shaft 16 rotates 90 degrees from this state, as shown in FIG.
It rises relative to the platen roller 14. The up/down selection state of this thermal head 66, 44, 67 is A3
Alternatively, it corresponds to the width of the selected recording paper 8 when recording on the recording paper 8 in A4 size and cutting it. When the pressurizing shaft 16 rotates 180 degrees from the zero reference angle as shown in FIG.
4 is pressed against the platen roller 14, and the other thermal head 67 is in a raised state relative to the platen roller 14. In this state, the recording paper 8 selected for Al or A2 size recording It corresponds to the pressure shaft 16.
As shown in FIG. 5, when the paper rotates 270 degrees from the zero reference angle, all the thermal heads 66, 44, 67 are pressed against the platen roller 14, which was selected for recording of AO size. Compatible with recording paper 8.

As shown in the flowchart of FIG. 6, the recording operation starts with the operator setting the continuous recording paper 8 in the holder IO (block 1).

Next, when the operator turns on the main switch (block 2), the clutch 70 is turned off, the clutch 78 is turned on, and the drive motor 68 is driven forward (block 3).
, the pressurizing shaft 16 rotates (block 4). Next, when the sensor 96 detects the P point of the first positioning plate 94, the control circuit 82 stops driving the motor 68 and stops the rotation of the pressure shaft 16 based on the output of the sensor 96 (block 5).
. As a result, 1. All heads 66, 44, 67 are raised relative to the platen roller 14 (block 6).

Next, the operator moves the recording paper 8 to the head 66.44.6.
7 and the platen roller 14 (block 7
). Next, the operator specifies the paper size using the panel keys (block 8). Next, when the drawing switch is turned on (block 9), the control circuit 82 executes judgment block 1.
Thermal bed 66.44.67 is down at 0
If the determination is negative, the clutch 70 is turned off, the clutch 78 is turned on, and the output shaft of the motor 68 is rotated in the forward direction by a predetermined amount (block 11). A thermal head corresponding to the width of the paper, for example 66, 44, 67, is lowered and pressed against the butylan roller 14 (block 12). Next, the clutch 70 is turned on, the clutch 78 is turned off, and the motor 6 is turned on.
The output shaft of No. 8 is driven in the normal rotation (block 13), and the output shaft of No. 8 is
While sending the image in a predetermined direction, the selected thermal head 66°64.67 is driven to perform drawing (block 14).
, when one frame of drawing is completed (block 15), the control circuit 82 transports the recording paper 8 by a predetermined amount (block 16), and then drives the loop cutter to cut the recording paper 8 according to the set paper size. Cutting is performed (block 17). Next, the motor 68 is reversely rotated to feed the recording paper a predetermined amount in the reverse direction (block 18). Next, the control circuit 82 determines whether or not to continue one drawing in a judgment block E9, and if it judges yes based on the input state of drawing data from the host computer, the process moves to block E9. If the judgment block 19 is negative, it is judged whether or not to turn off the main switch (power switch) 100 (block 16); if it is determined to be turned off, the main switch 100 is turned off (block 20), and processing is performed. Complete the action.

In 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. Also good. These head pressure shaft 16 and cam surfaces A, B,
C or the configuration of the cam plate is the head support means 50, 5.
Thermal heads 44.66 which they support 2,53
．． 67 constitutes a cam means for selectively displacing the platen roller 14 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. Furthermore, the motor that drives the cam means is not particularly limited to a platen roller drive motor. 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 automatically moves the thermal head up and down according to the paper width size of the recording paper, so it is possible to reduce the deterioration of the thermal head due to friction between the unused thermal head and the platen roller. At the same time, the power consumption required to drive the platen roller can be reduced. Furthermore, there are effects such as the ability to perform up-down control of the thermal head without preparing a special power device.

[Brief explanation of drawings]

Figure 1 is an explanatory diagram of the exterior, Figure 2 is an exterior diagram, Figure 3 is an exterior diagram, Figure 4 is an exterior diagram, Figure 5 is an explanatory diagram, Figure 6 is a flowchart, and Figure 7 is a block diagram. be. 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-x Rad pedestal, 56.56'-x Rad support, 60... Head support shaft, 62... Head pressure spring, 66.67... Thermal head, 68... Drive Motor, 70...Clutch, 72...Belt pulley, 74...Timing belt, 76...Belt pulley, 78...Clutch 6

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 head support means to support, and a selected one or selected two or more of these support means adjacent to each other in the line direction are separated from a position where the thermal head supported by the head support means presses against the platen roller. a power transmission mechanism that connects the cam means and the output shaft of the drive motor; a first clutch provided in the power transmission mechanism; and an output shaft of the drive motor; a second clutch disposed between a device interlocked with the output shaft; and a control circuit that controls the clutch and the drive motor, selects a thermal head according to the paper size, and presses the thermal head to the platen roller. A thermal recording device equipped with.