JP2510642Y2 - Thermal printer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a thermal printer applied to a label printer or the like for printing a barcode on a wide label sheet.

[Conventional technology]

Conventionally, a label printer that prints a bar code on a wide label paper uses a line thermal head having a long printing width as disclosed in Japanese Patent Laid-Open No. 61-266271, and the line thermal head is pressed against a platen. Has become.

In such a label printer, when the label paper is set between the platen and the line thermal head, the line thermal head has to be set far apart from the platen and set by hand, which makes the paper setting troublesome. was there.

[Problems to be solved by the device]

As described above, conventionally, when the paper is set between the platen and the head, the line thermal head has to be largely separated from the platen.

The present invention has been made in view of these problems, and provides a thermal printer capable of automatically setting a sheet between the platen and the thermal head without significantly separating the thermal head from the platen. It is intended to be provided.

[Means for solving the problem]

In order to achieve the above object, the present invention provides a platen rotatably supported by a body frame, a line thermal head that presses against the platen, a head frame that holds the line thermal head, and a body frame that is rotatable. A head arm that is pivotally supported on the head frame to rotatably support the head frame, a fixing means that fixes the head arm to the main body frame, and a head drive unit that rotates the head frame with the head arm fixed to the main body frame when setting paper. The head-up mechanism that moves the line thermal head away from the platen automatically, the feed roller that feeds the paper between the platen and the line thermal head, and the head-up mechanism separates the line thermal head when the paper is set. Next, a drive means for automatically rotating the feed roller is installed. Those were.

[Action]

According to the present invention, when the paper is set, the thermal head is separated from the platen with the head arm fixed to the main body frame, and in this state, the feed roller is rotated to feed the paper. Therefore, the thermal head is largely separated from the platen. The paper can be automatically set between the platen and the thermal head without the need to do so.

〔Example〕

 Embodiments of the present invention will be described below with reference to the drawings.

1 to 8 show an embodiment of the present invention.
In the figure, 1 is a main body frame, 2 is a platen rotatably supported by the main body frame 1, and 3 is a line thermal head that is in pressure contact with the platen 2. As shown in FIG. 2, the line thermal head 3 is fixed to the lower surface of the head base 4 and is swingably held by the head bracket 6 via the connecting shaft 5.

Fitting portions 8 are provided at both ends of the head base 4 to fit platen shafts 7 protruding from both ends of the platen 2. Further, the head bracket 6 is fixed between the head frames 9, 9 rotatably supported by the tips of the head arms 11, 11 via a support shaft 10. The head arms 11 and 11 are rotatably supported on the upper portion of the main body frame 1 via a support shaft 12, and as shown in FIG.
Both ends of the support shaft 10 are engaged with the recesses 14, 14 formed in the main body frame 1 by means of 3, 13, and are fixed to the main body frame 1. The head arms 11, 11 are urged to rotate by a spring (not shown) in a direction of separating the line thermal head 3 from the platen 2.

As shown in FIG. 2, the head arm 9, 9 has a support shaft 1
A pair of leaf springs 15, 15 attached to the outer periphery of 0 urges the line thermal head 3 to rotate in a direction of pressing it against the platen 2. One ends of the leaf springs 15, 15 are in contact with the rear end of the head bracket 6, and the other ends are locked by the head pressure adjusting cams 16, 16. As shown in FIGS. 4 (a) and 4 (b), the head pressure adjusting cams 16 and 16 have a plurality of flat portions 17 on their outer circumferences, and these flat portions 17 are rotated about the cam shaft 18. The head pressure is adjusted accordingly. Both ends of the cam shaft 18 have head arms 1
It is inserted into arcuate elongated holes 19 and 19 formed in 1 and 11, and is adapted to rotate integrally with the head frames 9 and 9 along the elongated holes 19 and 19.

Further, below the head arms 11 and 11, roll holders 23 and 24 for holding the supply shaft 21 and the take-up shaft 22 of the ink ribbon 20 are rotatably attached to the inner surfaces of the main body frame 1 which face each other. . The roll holder 23 holding the supply shaft 21 is provided with an ink ribbon loosening prevention gear 25 that prevents the ink ribbon 20 from loosening when the line thermal head 3 is pressed against the platen 2. This gear 25 has a gear 26 attached to the support shaft 12 as shown in FIG.
Rotation is transmitted through the intermediate gear 27,
The intermediate gear 27 has a built-in one-way clutch 28 that transmits the rotation of the intermediate gear 27 to the ink ribbon slack preventing gear 25 only when the gear 26 rotates in the arrow direction. An ink ribbon take-up gear 29 is provided on the roll holder 24 that holds the take-up shaft 22. This ink ribbon take-up gear
The one-way clutch (not shown) that rotates the roll holder 24 only in the winding direction is built in the 29, and is driven by a winding motor (not shown).

Label paper holding members 32, 32 that rotatably hold the roll-shaped label paper 30 via a holding shaft 31 are attached to the rear portion of the main body frame 1. The label paper 30 is guided to the vicinity of the feed roller 34 by a paper pan 33 provided at the bottom of the main body frame 1. A pinch roller 35 is in rolling contact with the feed roller 34, and the label paper 30 has both rollers 34, 35.
The rotation of the sheet passes through a paper pan 36 provided between the feed roller 34 and the platen 2, and is fed to a printing unit composed of the platen 2 and the line thermal head 3. A reflective paper sensor 37 for detecting the presence or absence of paper is attached to the paper pan 36. Further, the roller shaft 38 of the feed roller 34,
As shown in FIG. 6, a timing pulley 40 having an electromagnetic clutch 39 is attached. This timing pulley 40
The rotational force of the platen 2 is transmitted through the timing belt 41, and the feed roller 34 rotates in synchronization with the platen 2. The platen 2 is driven by the platen motor 42 and the timing belt 43.
And is driven via the timing pulley 44.

Relay rollers 46, 46 engaging with the head up cams 45, 45 are attached to the lower ends of the head frames 9, 9. The head up cams 45, 45 are for separating the line thermal head 3 from the platen 2 by pushing up the head frames 9, 9 via the relay rollers 46, 46 as shown in FIG. It is adapted to be driven by a head-up motor (not shown) as a drive source via a cam shaft 47 rotatably supported by the main body frame 1.

When setting the label paper on the thermal transfer printer configured as described above, first, the label paper 30 formed in a roll shape is rotatably held by the holding members 32, 32 attached to the rear portion of the main body frame 1. The leading edge of the label sheet 30 is inserted between the feed roller 34 and the pinch roller 35 through a paper pan 33 provided at the bottom of the main body frame 1. When a paper feed button (not shown) is pressed in this state, the feed operation is started according to the flow shown in FIG.

That is, first, in step S1, the paper sensor 37
After confirming that is OFF, the head-up motor (not shown) rotates by a predetermined amount, and the head-up cams 45, 45 are attached to the lower ends of the head frames 9, 9 by the relay rollers 46, 46.
(Step S2). As a result, the head frames 9, 9 are pushed upward by the head-up cams 45, 45, and the line thermal head 3 is separated from the platen 2.

Next, in this state, the electromagnetic clutch 39 of the timing pulley 40
ON to drive the platen motor 40 (step S3),
The platen 2 and the feed roller 34 are rotated. As a result, the label paper 30 inserted between the feed roller 34 and the pinch roller 35 is fed to the printing unit by the rotation of the feed roller 34. When the leading edge of the label sheet 30 is detected by the paper sensor 37 (step S
4), the platen motor 42 rotates by a fixed amount and stops (step S5). At this time, the electromagnetic clutch 39 is also turned off.
Becomes As a result, the leading edge of the label sheet 30 is set between the platen 2 and the line thermal head 3. After that, the head-up motor is driven again by a predetermined amount (step S6), the head frames 9, 9 pushed up by the head-up cams 45, 45 are lowered, and the line thermal head 3 is brought into pressure contact with the platen 2 again.

As described above, in this embodiment, since the line thermal head 3 is separated from the platen 2 in a state where the head arms 11 and 11 are fixed to the main body frame 1 when the paper is set, the thermal head is not greatly separated from the platen and the paper is Can be automatically set between the platen and the thermal head. The present invention is not limited to the above embodiment, and various design changes can be made.

[Effect of device]

As described above, according to the present invention, the thermal head separates from the platen while the head arm is fixed to the main body frame when the paper is set, and the feed roller rotates to feed the paper in this state. The paper can be automatically set between the platen and the thermal head without being largely separated from the platen.

[Brief description of drawings]

1 to 8 show an embodiment of a thermal printer according to the present invention, FIG. 1 is an overall configuration diagram, FIG. 2 is a detailed view showing a head frame, FIG. 3 is a detailed view showing a head arm, 4 (a) and 4 (b) are views showing the structure of the head pressure adjusting cam, FIG. 5 is a detailed view showing the ink ribbon slack preventing mechanism, and FIG. 6 is a perspective view showing one end of the feed roller.
FIG. 7 is a diagram showing a state in which the thermal head is separated from the platen, and FIG. 8 is a flow chart showing a sheet feeding operation. 1 ... Main body frame, 2 ... Platen, 3 ... Line thermal head, 6 ... Head bracket, 9 ... Head frame,
11 ... Head arm, 13 ... Fixed lever, 15 ... Leaf spring, 16 ...
Head pressure adjusting cam, 20 ... Ink ribbon, 25 ... Ink ribbon loosening prevention gear, 29 ... Ink ribbon winding gear, 30 ... Label paper, 34 ... Feed roller, 37 ... Paper sensor,
42 ... Platen motor, 45 ... Head up cam, 46 ... Relay roller.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Ikuzo Sugiura, 570, Ohito, Ohito-cho, Takata-gun, Shizuoka Tokyo Electric Engineering Co., Ltd. (56) References JP 61-266262 (JP, A) 107253 (JP, U)

Claims (1)

(57) [Scope of utility model registration request] 1. A platen rotatably supported by a main body frame, a line thermal head in pressure contact with the platen, a head frame holding the line thermal head, and a rotatably pivotally supported by the main body frame. A head arm that rotatably supports the head frame, a fixing unit that fixes the head arm to the main body frame, and a head that rotates the head frame with a drive source while the head arm is fixed to the main body frame when setting paper. A head-up mechanism that moves the line thermal head away from the platen automatically; a feed roller that feeds a sheet between the platen and the line thermal head; Automatically rotate the feed roller following head separation Thermal printer characterized by comprising a dynamic driving means.