JPS62152882A - Position-adjusting mechanism for thermal head - Google Patents

Abstract

PURPOSE:To print while constantly maintaining the printing position of a thermal head and a platen in an appropriate positional relationship and ensure high-accuracy printing, by supporting the thermal head through a movable intermediate plate so that the head can be moved relative to a head support frame, and engaging a thermal head position adjusting body (which is fitted to the intermediate plate or the thermal head) to a platen shaft. CONSTITUTION:When designing, the center line of a U-shaped notched part 37a of a thermal head position adjusting body 37 is set to be located on a line passing through the printing position of a thermal head 33. Therefore, even when a platen 36 is shifted in a horizontal direction, the head 33 is followingly moved together with the position-adjusting body 37, so that the printing position of the head 33 can be located on a line normal to the platen 36. Accordingly, even when vibration or the like is generated in operation of the device, a printing operation can be performed while maintaining the thermal head 33 and the platen 36 in an appropriate positional relationship, and clear printing can be performed with high accuracy.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a thermal head position adjustment mechanism for a 7-mark printing device, and in particular to a thermal head position adjustment mechanism with improved means for positioning the thermal head and the platen. Regarding the J adjustment mechanism.

[Conventional technology]

There are various types of thermal printing apparatuses for sending out a label mount including a label printed by a thermal head. In other words, after printing the desired items on the label pasted on the label backing paper, the label is peeled off and the label backing paper is rolled up. A format in which the label is sent out as it is, a format in which the label is wound onto a take-up roller with the label attached to the label mount, and a format in which the label mount is cut with a predetermined number of labels affixed.
There is a format in which the desired printing item □ is printed on a sheet without a label, and the sheet is sent out and cut.

In any of these types of thermal printing devices, if the thermal head and platen are not in a fixed positional relationship,
Desired items cannot be clearly printed on labels, etc.

Therefore, conventionally, a position adjustment mechanism as shown in FIG. 2 has been used as a position adjustment means for the thermal head and the platen. That is, this mechanism is shown centering around the support shaft 1 (
b) A hole 3 is formed in the middle part of the head support frame 2 that rotates in the direction of the arrow, and a screw 4 having an outer diameter smaller than the diameter of this hole 3 is passed through the hole 3 to attach the thermal head. 5, the thermal head 5
is supported by a head support frame 2.

A spring 6 presses the end of the head support frame 2 opposite to the support shaft 1 with a predetermined pressing force.

A platen 8 is provided so as to be rotatably in contact with the printing position which is to become the printing section 7 of the thermal pad 5 supported as described above.

Furthermore, the printing section 7 of the thermal head 5 and the platen 8
For example, a transfer ribbon 9 and a label mount 11 to which a label 10 is attached are fed into the space between the two, and by heating the printing section 7, the printed content is transferred and printed onto the label 10 through the ribbon 9.

By the way, in the above-described apparatus, when the apparatus is shipped or when the thermal head is replaced, the thermal head 5 is fixed using the screw 4 so that the printing part 7 of the thermal head 5 is located on the normal line position of the platen 8. The position is being adjusted.

[Problem that the invention seeks to solve]

However, the thermal head position adjustment mechanism as described above is
Unless the apparatus is actually operated and the density of the print content printed on the label 10 is observed, it is impossible to judge whether the thermal head 5 and the platen 8 are in the appropriate positions. Moreover, this position adjustment requires repeating the printing operation several times and observing the density of the print, otherwise it will be difficult to set the print position of the thermal head 5 and the platen 8 in an appropriate positional relationship, making the position adjustment work extremely difficult. It becomes complicated. Additionally, during the actual printing operation, positional deviations may occur due to vibrations from the drive source, external shocks, etc. In this case as well, it is necessary to perform position adjustment, and the position adjustment work is performed in the same way as described above. It's a nuisance.

Therefore, the present invention was developed with the above points in mind. By simply assembling the printer, the printing position of the thermal head and the platen can be adjusted to the appropriate positions, and the printing position and platen can be adjusted to the appropriate positions. To provide a position adjustment mechanism for a thermal head capable of automatically moving the thermal head to follow the positional deviation even if a platen or the like is displaced and setting the printing position of the thermal head and the platen at appropriate positions. There is a particular thing.

[Means for solving problems]

In order to achieve the above objects, the present invention supports a thermal head via a movable relay plate so as to be movable with respect to a head support frame, and also allows the thermal head position adjustment to be performed on the movable relay plate or the thermal head. The position adjustment body is attached to the shaft of the platen.

[Effect]

Therefore, by using the above means, the present invention
When the platen moves due to misalignment of the thermal head or platen, the movable relay plate moves via the thermal/rad position adjustment body, and with this movement, the thermal head, which moves integrally with the movable relay plate, moves. In order to
Even if vibration or other causes of positional deviation occur in the device, printing can be performed while maintaining an appropriate positional relationship between the printing position of the thermal/rad printer and the platen, and clear printing can be ensured over a long period of time.

〔Example〕

Hereinafter, one embodiment of the present invention will be described with reference to FIG. In the figure, reference numeral 21 denotes a head having a predetermined width in the depth direction of the page, for example, equal to or larger than the width of the label mount 22, and a desired length in the moving direction of the label mount 22. It is a support frame.

This head support frame 21 has screw holes 23 formed at both ends in the depth direction (width direction) of the drawing, and one end of the head support frame 21 rotates in the direction of the arrow (b) in the figure with a support shaft 24 as the center of rotation. It is movably supported, and the other end is pressed with a desired pressing force by an elastic member 25 such as a spring.

Reference numeral 26 denotes a movable relay plate in which a hole 27 is formed whose center axis is on the central axis of the screw hole 23. A base 28 is inserted into the flange receiver and screwed into a screw hole 23 of the head support frame 21 with a screw 29.

That is, as a parallel movement mechanism for the movable relay plate 26, the diameter of the hole 27 is formed to be larger than the screw hole 23, and a collar with an outer diameter smaller than the hole diameter is provided in the hole 27. In the support with a support, the stand 2B is inserted to form a gap 30, and in the support with a collar, the brim surface of the stand 28 is set to have some gap 31 from the face of the movable relay plate 26,
In this state, by screwing the screw 29 into the screw hole 23 of the head support frame 21 through the hole of the base 28, the relay plate 26 is attached to the support frame 21.
The structure is such that it moves with play. Then, the thermal head 33 is screwed to this movable relay plate 26 from the back side with flat head screws 32, and the movable relay plate 26
The structure is such that the thermal head 33 and the thermal head 33 move together.

The label mount 22 on which a ribbon 34 and a label 35 are attached to the printing surface side of the thermal head 33 is supplied from the right end side in the figure to the printing position 35 of the thermal head 33. The head support frame 2 is pressed with a predetermined pressing force so that the label mount 22 is sandwiched between the thermal head 33 and the thermal head 33 .

Reference numeral 37 denotes a platen position adjustment body, which has its base side fixed to the relay plate 26 or the thermal head 33 side, and has a U-shaped notch 37a formed at its end side. Then, U of this thermal head position adjustment body 37
The letter-shaped notch 37a is connected to the platen shaft 3 of the platen 36.
The moving relay plate 26 is attached to a bearing 38 attached to the movable relay plate 6a.
The position of the platen 36 is adjusted by a thermal head position adjustment body 37 that moves integrally with the thermal head 33.

Therefore, according to the above configuration, if the center line of the U-shaped notch 37a of the thermal head position adjustment body 37 is set on the line of the printing position of the thermal head 33 at the time of design, for example, shipping The thermal head 33 and platen 36 are aligned so that the head 33 can follow along with the thermal head position adjustment body 37 even if the platen 36 shifts horizontally due to vibrations of the device drive source, etc., as well as when replacing the head. Thermal head 3 on the line position
3 can be made to coincide with each other, and as a result, even if vibrations occur during operation of the device, the thermal head 33 and platen 36 can be maintained in an appropriate positional relationship to perform the printing operation, resulting in clear and clear printing. Can print with high precision. Furthermore, since the notch 37a of the thermal head position adjustment body 37 is U-shaped, the thermal head 33 can be lifted up when necessary, making maintenance of the apparatus easier.

Inspection, replacement of the ribbon 34 and label sheet 22, etc. can be easily performed. Further, since the bearing 38 is attached to the platen shaft 36a and is engaged with the thermal head position adjustment body 37, there is less wear on the thermal head position d:A assembly 37 and the platen shaft 36a.

In the above embodiment, the head support frame 21 and the movable relay plate 26 are screwed together, but they may be supported using bolts and nuts. In addition, although the thermal head position adjustment body 37 has a U-shaped notch, it may have a V-shape or other shapes.

In addition, the present invention can be implemented with various modifications without departing from the gist thereof.

〔Effect of the invention〕

As described in detail above, according to the present invention, there is no need to adjust the relative positions of the thermal head and the platen, and even if the thermal head and the platen are misaligned due to vibration of the device, the printing position of the thermal head and the platen can be adjusted. It is possible to provide a position adjustment mechanism for a thermal head that can perform printing while always maintaining an appropriate positional relationship and can perform highly accurate printing.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway sectional view showing an embodiment of a thermal head position adjustment mechanism according to the present invention, and FIG. 2 is a partially cutaway sectional view showing a conventional position adjustment mechanism. 21... Head support frame, 22... Label mount, 23... Screw hole, 26... Moving relay board, 27...
... hole, 28 ... holder with flange is stand, 29 ... screw, 30° 31 ... gap, 33 ... thermal head,
34... Ribbon, 35... Label, 36... Platen, 36a... Platen shaft, 37... Thermal head position adjustment body, 37a... Notch, 38... Bearing. Applicant's agent Patent attorney Takehiko Suzue Figure 2

Claims (1)

[Claims] a movable relay plate provided between the head support frame and the thermal head and attached to the head support frame so as to move integrally with the thermal head along the surface of the head support frame; a platen provided so as to be in contact with the printing position of the head; fixed to the movable relay plate or the thermal head, for causing the printing position of the thermal head to follow the movement of the platen so as to be always in contact with the platen; 1. A thermal head position adjustment mechanism comprising: and a thermal head position adjustment body attached to a platen shaft.