JPH0447974A - Thermal head supporting device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention provides a thermal head that switches between a printing operation state in which the thermal head is urged toward the platen side with a predetermined pressure and a standby state in which the thermal head is lifted in a direction away from the platen side. The present invention relates to a support device.

A conventional printer device for printing on labels is constructed as shown in FIG. The label 1 is pasted on a strip-shaped release mount 2 at a fixed pitch. Wrapping body 3 of peel-off mount 2 with label
is attached to the supply shaft 4, and the peeling mount 2 pulled out from the winding body 3 passes between the platen roller 5 and the thermal head 6, and is further passed through the peeling plate 7. The hook is passed to the take-up shaft IO via between the drive roller 8 and the pinch roller 9, and the platen roller 5, the drive roller 8, and the take-up shaft IO are connected to each other.
O are each rotated in the direction of arrow A at a printing speed by a motor (not shown). The thermal head 6 is pivotally supported by a support shaft 11 and is biased in the direction of arrow B by a spring (not shown).

FIG. 5 shows the actual structure of the thermal head support device 12 used for mounting the thermal head 6. As shown in FIG. The support shaft 11 is a fixed body frame 13a.

The thermal head 6 is supported by the arrow B by a coil spring 14 whose one end engages with the body frame 13b and the other end engages with the lower surface of the thermal head 6.
It is biased in the opposite direction (direction of arrow C). In addition to the thermal head 6 , a press plate 15 is rotatably supported on the support shaft 11 , and a compression spring 16 is interposed between the back surface of the press plate 15 and the top surface of the thermal head 6 . The pressing plate 15 is pressed by a cam body 18 attached to an operating shaft 17 supported by the body frames 13a and 13b, and the thermal head is pressed against the platen roll by the urging force of the compression spring 1B against the urging force of the coil spring 14. It is pressed to the side of 5.

In such a thermal head support device 12, an operator operates the operating lever IS to place the thermal head 6 in a standby state where it is lifted from the platen roll 5, and then the label-attached peeling paper 2 is hung and replaced. .

Problems to be Solved by the Invention In such a conventional configuration, in order to move the thermal head 6 between a printing operation state and a standby state, and to press the thermal head 6 appropriately against the platen roll 5 side in the printing operation state, is two springs 14. te is required.

In addition, the operating shaft 17 is driven by a motor, and the thermal head 6 is
Even if an attempt is made to configure the printer to switch between a printing operation state and a standby state, unless the stop position of the operating shaft 17 at that time is accurately positioned, proper pressing will not be achieved in the printing operation state. be.

SUMMARY OF THE INVENTION An object of the present invention is to provide a thermal head support device that requires only one spring and that can provide a proper pressing state during printing operation without having to accurately position the stop position of the operating shaft. .

Means for Solving the Problems The thermal head support device of the present invention includes a guide means for linearly moving the thermal head in a radial direction with respect to the rotation center of the platen roll, and a rotation axis centered along the line direction of the thermal head. The present invention is characterized in that it includes an extending camshaft and a spring whose one end is connected to the thermal head side and the other end is connected to the camshaft side.

According to this configuration, the thermal head supported by the guide means so as to be linearly movable in a radial direction with respect to the rotation center of the platen roll is aligned with the rotation axis along the line direction of the thermal head and this thermal head during printing operation. is pressed against the platen roll by the biasing force of the spring that connects the camshaft to the extending camshaft. When the camshaft is rotated, the thermal head is pulled up in the direction supported by the guide means via the spring and placed in a standby state.

EXAMPLE Hereinafter, an example of the present invention will be described based on FIGS. 1 to 3. Components having the same functions as in FIGS. 4 and 5 showing the conventional example will be described with the same reference numerals.

1 and 2 show a thermal head support device 12 of the present invention.
Indicates the printing operation status. The end face type thermal head 6 attached to the thermal head support frame 20 is guided by the guide means 21 to the body frame 13a.

It is supported from 13b. Here, the guide means 21 includes folded pieces 22a, 22 of the fuselage frames 13a, 13b.
b, and shafts 23a and 23b, one end of which is inserted through the folded pieces 22a and 22b and the other end of which is fixed to the thermal head support frame 20. can move in a straight line along the radiation line. 24 is a camshaft, which is attached to the fuselage frame 13a;
Both ends are supported by 13b, and the rotation axis is the thermal head θ.
Coil springs 2Ga and 2[ib are interposed between the protrusions 25a and 25b of the camshaft 24 and the thermal head support frame 20.

During printing operation, coil spring 2G is activated as shown in Figure 2.
The thermal head 6 is pressed against the platen roll 5 by a biasing force of 2 Gb.

When the cam shaft 24 is rotated by a motor or the like as shown in FIG. 3, the thermal head support frame 20 is moved by the coil springs 26a, 2
It is pulled up via 8b and placed in a standby state.

When the camshaft 24 is rotated by a motor or the like as shown in FIG. 2, the thermal head support frame 2o is moved by the coil springs 2Ba,
2Gb to enter the printing operation state, and the stopping position of the camshaft 24 at this time is not accurate (however, the amount of error is absorbed by the coil springs 2Ba and 26b, and an appropriate pressing force is obtained.

Effects of the Invention As described above, according to the present invention, there is provided a guide means for linearly moving the thermal head in a radial direction with respect to the rotation center of the platen roll, and a cam shaft whose rotation axis extends along the line direction of the thermal head. and a spring whose one end is connected to the thermal head side and the other end is connected to the camshaft side, so that the thermal head supported by the guide means is able to move between the thermal head and this thermal head in the printing operation state. It is pressed against the platen roll by the biasing force of a spring that connects the camshaft whose rotation axis extends along the line direction of the camshaft.

Therefore, only one spring is required, and even if the stop position of the operating shaft is not positioned accurately, the error amount is absorbed by the spring, and proper pressing can be achieved during printing operation. .

[Brief explanation of the drawing]

FIG. 1 is a perspective view of an embodiment of the thermal head support device of the present invention, FIG. 2 is an explanatory diagram of the printing operation state of the device, FIG. 3 is an explanatory diagram of the standby state of the device, and FIG. FIG. 5, which is a block diagram of a printer device, is a perspective view of a conventional thermal head support device. 5...Platen roll, 6...Thermal head, 2
0... Thermal Rad support frame, 21... Guide means,
24...Camshaft, 2Ga, 28b...Coil spring [
spring].

Claims (1)

[Claims] 1. A guide means for linearly moving the thermal head in a radial direction with respect to the rotation center of the platen roll, a cam shaft whose rotation axis extends along the line direction of the thermal head, and one end connected to the thermal head side. and a spring whose other end is connected to the camshaft side.