JPH06227003A - Piezoelectric printing head - Google Patents

Abstract

PURPOSE:To provide a piezoelectric printing head by preventing interference to other printing element caused by vibration of a printing element from occurring when the head is driven at high speed to enable printing with high quality with stabilized wire action in relating to the piezoelectric printing head using a piezoelectric actuator. CONSTITUTION:A piezoelectric printing head prepd. by mounting a plurality of printing elements 4 constituted by connecting a piezoelectric actuator 5 provided with a piezoelectric element 8 with a movable body 6 provided with a wire 14 through an enlarged mechanism part 7 on an integrated base 31 in a specified pitch, has a constitution wherein both ends of the channels are connected between each two printing elements 4 on a base 31.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a piezoelectric print head using a piezoelectric actuator.

There is a limit to the electromagnetic system to meet the demand for high speed of the impact printer, and therefore, a piezoelectric actuator using a piezoelectric element is reviewed for high speed printing. In order to achieve high speed using this piezoelectric actuator, it is necessary to stabilize the operation of the piezoelectric actuator in order to achieve high print quality.

[0003]

2. Description of the Related Art The structure of a conventional piezoelectric print head using a piezoelectric actuator is shown in FIG. 6A is a side sectional view of the piezoelectric print head, FIG. 6B is a partially cutaway perspective view of the same, and the piezoelectric print head 1 has a wire guide nose 2a.
A plurality of printing elements 4 on an integrated base 3 suspended in a heat sink (housing) 2 in which
It is configured to be attached at a predetermined pitch in the circumferential direction.

The printing element 4 is a piezoelectric actuator 5.
And the movable body 6 are connected to each other via the expansion mechanism section 7. The piezoelectric actuator 5 includes blocks 9, 1 above and below the piezoelectric element 8.
The piezoelectric element 8 was obtained by stacking a plurality of piezoelectric ceramic green sheets each having a metal paste film to be an internal electrode formed on one surface thereof, and then firing them together. It is a thing. The piezoelectric element 8 has
A preload is applied to the blocks 9 and 10 by a preload spring 11 whose ends are fixed.

The movable body 6 has a beam 1 on the armature 12.
3 is fixed, and the wire 14 is fixed to the tip of the beam 13. The enlarging mechanism section 7 is composed of two leaf springs 15 and 16 arranged substantially in parallel. Leaf spring 15
Has one end fixed to a fixing member 17 fixed to the base 3 and the other end fixed to the armature 12. One end of the leaf spring 16 is fixed to the block 9 and the armature 1
The other end is fixed to 2.

Although not shown, the piezoelectric print head 1 having such a structure is mounted on a carrier that can move forward and backward along a platen around which a recording paper is wound, and operates at a predetermined time to perform printing. The details of the operation are as follows.

During non-printing, each piezoelectric element 8 is not energized, and in this state, the wire 14 of each printing element 4 is retracted from the platen.

At the time of printing, the piezoelectric element 8 of a predetermined printing element 14 is energized for a predetermined time at a predetermined time to operate the printing element 4. The energization is performed by supplying power to the connector 20 fixed to the printed board 19 attached to the bottom of the heat sink 2. As a result, the piezoelectric element 8 is energized from the terminal 22 having the lead wire 21 connected to the printed board 19, and the piezoelectric element 8 is displaced upward.

Due to this displacement, the leaf spring 16 is pushed upward, the movable body 6 is rotated in the printing direction, and the wire 14 is projected to perform printing. At the time of completion of printing, the energization to the piezoelectric element 8 is stopped, and the movable body 6, the piezoelectric element 8 and the enlarging mechanism section 7 that have completed the printing return to the original state.

[0010]

In the conventional piezoelectric print head having such a structure and operation, when a predetermined print element is driven at a high speed, the base near the print element vibrates and is adjacent to it. There is a problem that it is transmitted to another printing element and causes it to malfunction.

It is an object of the present invention to provide a piezoelectric print head which prevents interference with other print elements due to vibration of the print element when the head is driven at high speed, and enables high quality printing with stable wire operation. Has an aim.

[0012]

In order to achieve the above object, according to the present invention, a plurality of printing elements are formed by connecting a piezoelectric actuator having a piezoelectric element and a movable body having a wire by an expansion mechanism. , A piezoelectric print head, which is mounted on an integrated base at a predetermined pitch in the circumferential direction, in the base between the respective print elements,
A configuration (first configuration) is characterized in that a groove having both ends connected is formed.

Further, a plurality of printing elements, which are formed by connecting a piezoelectric actuator having a piezoelectric element and a movable body having a wire by an enlarging mechanism, are provided on an integral type base at a predetermined pitch in the circumferential direction. In the attached piezoelectric print head, a piezoelectric actuator for braking, which is driven in synchronization with the piezoelectric actuator, is attached to the back side of the base so as to dampen the vibration of the base during a printing operation ( The second configuration).

[0014]

In the case of the first construction, the vibration of the base during the operation of a certain print element is canceled by the groove between the print element and the adjacent print element and is not transmitted to the adjacent print element side. In the case of the second configuration, the vibration of the base during the operation of a certain print element is damped by the operation of the braking piezoelectric actuator on the back side of the base. As described above, in any of the configurations, the vibration of the base plate caused by the operation of a certain print element does not affect the other print elements.

[0015]

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

FIG. 1 and FIG. 2 show a first embodiment.

FIG. 1 is a partially cutaway perspective view showing the structure of the main part of the piezoelectric print head of this embodiment, in which 31 is a base (corresponding to the conventional base 3). The same reference numerals are used for the same members as the conventional ones. Although not shown, the base 31 is suspended in a heat sink similar to the conventional one, and a groove 32 is formed between the print elements 4 in the base 31, and both ends of the groove 32 are connected. There is.

As described above, in this example, since the groove 32 is formed in the base 31 between the respective printing elements 4, the vibration of the base 31 during the operation of a certain printing element 4 is different from that of the adjacent printing element 4. It is erased by the groove 32 between and is not transmitted to the adjacent printing element 4 side. Therefore, the operation of the wire is stable and high quality printing is realized.

FIG. 2 shows an application example. This example is different from FIG. 1 in that the groove 32 is filled with a vibration-proof member 33. In this case, since the anti-vibration effect of the anti-vibration member 33 is added, a further effect can be obtained.

A second embodiment is shown in FIGS.

FIG. 3 is a side sectional view of the piezoelectric print head of this embodiment, in which 41 is a heat sink and 42 is a braking piezoelectric actuator. The braking piezoelectric actuator 42 has a structure similar to that of the piezoelectric actuator 5, and the upper end of the auxiliary base 4 is fixed to the base 3 behind the center of the base 3.
The lower end portions are fixed to 3 respectively. The electrode of each piezoelectric actuator 5 and the electrode of the braking piezoelectric actuator 42 are connected to the printed board 1 through the lead wire 44 and the lead wire 45.
9 to receive power supply from the connector 20.

When a certain piezoelectric actuator 5 is energized for a predetermined time to activate the printing element 4, the braking piezoelectric actuator 42 is energized for a predetermined time and driven synchronously. Thus, the deformation (vibration) of the base 3 caused by the operation of the printing element 4 is canceled by the displacement of the braking piezoelectric actuator 42.

In the case of this example, not only the same effects as in the previous example can be obtained, but also the vibration and deformation of the base 3 are reduced. Instability of movement is improved,
Higher printing quality is realized.

FIG. 4 is a side sectional view of another piezoelectric print head of this embodiment. In this case, the same number of braking piezoelectric actuators 42 as the printing elements 4 are prepared, and the braking piezoelectric actuators 42 are arranged concentrically on the back side of the piezoelectric actuators 5 of the printing elements 4.

When activating a certain printing element 4, the braking piezoelectric actuator 42 on the back side of the piezoelectric actuator 5 of the printing element 4 is synchronously driven. In this case, since the braking piezoelectric actuator 42 operates at the same position as the operating piezoelectric actuator 5 on the base 3, the above effect is more effectively realized.

FIG. 5 shows an example of the structure of the piezoelectric actuator group shown in FIG. As is apparent from this figure, the plurality of braking piezoelectric actuators 42 are mounted on the base plate 46 and fixed by fixing the base plate 46 to the auxiliary base 43. By adopting this configuration, it becomes possible to accurately and easily mount a plurality of braking piezoelectric actuators 42.

[0027]

As described above, according to the present invention, it is possible to prevent the vibration and deformation of the base by the piezoelectric actuator when the piezoelectric print head is driven at a high speed from propagating to and interfering with other piezoelectric actuators. Therefore, the operation of the wire is stable and high-quality printing is realized.

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view showing a main structure of a piezoelectric print head according to a first embodiment of the present invention.

FIG. 2 is a partially cutaway perspective view showing an application example of the first embodiment of the present invention.

FIG. 3 is a side sectional view of a piezoelectric print head according to a second embodiment of the present invention.

FIG. 4 is a side sectional view of another piezoelectric print head according to the second embodiment of the present invention.

5 is a perspective view showing a configuration example of a braking piezoelectric actuator group in FIG. 4. FIG.

FIG. 6 is a structural explanatory view of a conventional piezoelectric print head.
FIG. 6A is a side sectional view of the piezoelectric print head, and FIG. 6B is a partially cutaway perspective view of the same.

[Explanation of symbols]

 3, 31 Base 4 Printing Element 5 Piezoelectric Actuator 6 Movable Body 7 Enlargement Mechanism Section 8 Piezoelectric Element 14 Wire 32 Groove 33 Anti-Vibration Member 42 Piezoelectric Actuator for Braking

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Shigeo Miura 1015 Kamiodanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture, Fujitsu Limited (72) Inventor Yuji Oshime, 1015, Kamedotachu, Nakahara-ku, Kawasaki City, Kanagawa Prefecture, Fujitsu Limited

Claims (2)

[Claims] 1. A plurality of printing elements (1) comprising a piezoelectric actuator (5) provided with a piezoelectric element (8) and a movable body (6) provided with a wire (14) connected by a magnifying mechanism (7). 4) a piezoelectric print head in which a fixed pitch is circumferentially attached to an integrated base (31), and the base (31) is provided between the print elements (4).
A piezoelectric print head having a groove (32) having both ends connected to each other. 2. A plurality of printing elements comprising a piezoelectric actuator (5) having a piezoelectric element (8) and a movable body (6) having a wire (14) connected by an enlarging mechanism (7). In a piezoelectric print head in which 4) is attached to an integrated base (3) at a predetermined pitch in the circumferential direction, a braking driven synchronously with the piezoelectric actuator (5) is provided on the back side of the base (3). Piezoelectric actuator (4
2. A piezoelectric print head, wherein 2) is attached so as to dampen the vibration of the base (3) during a printing operation.