JPH01271254A - Printing head - Google Patents

Abstract

PURPOSE:To eliminate the movement of the center of a support shaft at the time of printing, to achieve the stabilization and speedup of printing operation and to obtain sufficient impact force, by arranging the support axis of a movable body at the almost center of the straight line connecting the centers of the contact point parts with the movable body of a pair of drive elements. CONSTITUTION:A current is supplied to drive elements 2, 3 for a predetermined time at the time of printing. The drive elements 2, 3 are respectively displaced in the directions shown by arrows by this current supply to revolve a movable body 1 around a support shaft 4 in a printing direction and printing is performed by the printing member (e.g., wire) 5 provided to the leading end of the movable body 1. At this time, the drive elements 2, 3 are present at the positions of almost point symmetry from the center of the support shaft 4 to impart torques to the movable body 1 in the same direction. As a result, the movement of the center of the support shaft 4 being the center of revolution is almost eliminated and printing operation becomes stable and high speed driving becomes possible and sufficient impact force can be obtained.

Description

[Detailed Description of the Invention] [Summary] A print head that prints by rotating a movable body equipped with a printing member such as a printing wire by displacement of a drive element such as a piezoelectric element, which achieves high speed due to stable operation. The purpose is to make it possible to drive and to obtain sufficient impact force.The movable body is rotatably supported on a support shaft and has a printing member at the tip, and the movable body is connected to the movable body and displaces when energized. and a drive element that rotates the movable body in the printing direction, the drive element being provided as a pair facing the movable body, and each drive element being connected to the movable body of each drive element. The support shaft is disposed approximately at the center of a straight line connecting the centers of the connecting portions.

[Industrial application field]

The present invention relates to a print head that performs printing by rotating a movable body provided with a printing member such as a printing wire by displacement of a drive element such as a piezoelectric element.

[Conventional technology]

In recent years, there has been a strong demand for higher speed printing heads for impact printers, and conventional electromagnetic print heads such as release type and suction type are reaching their limits. Therefore, print heads using driving elements such as piezoelectric elements with high response speed have been developed. This piezoelectric element is shown, for example, in Nikkei Mechanical, P. 92, published March 1211, 1984. After laminating the ceramic Green Sea-1, the material obtained by performing bulk C firing is used.

[Problem to be solved by the invention 1.7] In this type of print head, the displacement of the drive element is minute, so various magnifying mechanisms have been tried to magnify this, but it is difficult to smoothly magnify the displacement. It was difficult to do so, and there were various problems such as unstable operation and inability to obtain sufficient impact force.

SUMMARY OF THE INVENTION An object of the present invention is to provide a print head that has stable operation, can be driven at high speed, and can obtain sufficient force for the impact 1.

[Means for solving the problem] Fig. 1 is a diagram explaining the principle of the present invention, in which 1 is a movable body, 2 is a movable body, and 2 is a movable body;
．． 3 is a driving element such as a laminated piezoelectric element.

The movable body 1 is rotatably supported by a support shaft 4 whose both ends are supported by a frame of the apparatus, etc., and has a printing member 5 such as a wire or a chip at its tip.

The drive element 2 is connected to the L surface of the movable body 1 on the left side of the support shaft 4, and the drive element 3 is connected to the lower surface of the movable body 1 on the right side of the support shaft 4. It is located approximately at the center of the straight line connecting the centers 01 and 0□ of the connecting portion with the movable body 1 of .3. Each drive element 2.3 is adapted to be displaced in a direction that rotates the movable body 1 in the printing direction (counterclockwise in FIG. 1) when energized.

[Effect]

During printing, each drive element 2.3 is energized for a predetermined period of time. As a result, each of the drive elements 2 and 3 is displaced in the direction of the arrow, and the movable body 1 is rotated in the printing direction to cause the printing member 5 to perform printing. If the displacement of the drive element 3 in this case is δ, the displacement (printing stroke) δ of the printing member 5 is as follows.

1°S=δ・-111 During this printing operation, each driving element 2.3 is located at a position approximately symmetrical to the center of the support shaft 4 and applies torque in the same direction to the movable body 1, so that it rotates. The movement of the center is almost eliminated, the movement is stable, and sufficient impact force can be obtained.

Energization to the drive element 2.3 is stopped immediately before printing is completed, and the printing member 5 that has completed printing returns to its original state together with the movable body 1 as the drive element 2.3 returns.

〔Example〕

The invention will now be described in detail with reference to FIG.

FIG. 2(a) is a plan view showing the structure of the print head according to the present invention, FIG. 2(b) is a front view of the same, and FIG. 2(C) is a side view of the same. /-mu. Note that the same members as in FIG. 1 are given the same reference numerals.

The printer 11 is integrally equipped with a pair of spindle supports 12.12, and both ends of the spindle 4 are supported by the spindle supports 12.12.

Further, each drive element 2.3 has a base that is connected to the printer 1, respectively.
1, and the tip part is fixed to the movable body 1 as shown in FIG.
is connected to.

During printing, each drive element 2.3 is energized for a predetermined period of time. As a result, the movable body 1 receives torque in the same direction from each of the drive elements 2.3, which are arranged at approximately point-symmetrical positions from the center of the support shaft 4.
The movable body 1 is rotated counterclockwise in FIG. 2(e), and printing is performed by the printing member 5. During this operation, there is almost no movement of the center of rotation, the operation is stable, and sufficient impact force can be obtained.

The energization to the driving element 2.3 is stopped immediately before printing is completed, and the printing member 5 that has completed printing returns to its original state together with the movable body 1 as the driving element 2.3 returns.

〔Effect of the invention〕

As described above, according to the present invention, the support shaft is disposed approximately at the center of the straight line connecting the centers of the contact portions of the pair of drive elements with the movable body, and each drive element causes the movable body to Since torque is applied in the printing direction, there is no movement of the center of the spindle during printing, resulting in stable operation and high-speed driving. In addition, sufficient impact force can be obtained.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of the principle of the present invention, and FIGS. 2(a), (b), and (C) are structural explanatory diagrams of a print head according to an embodiment of the present invention. In the figure, 1 is a movable body; 2. 3 is a drive element, 4 is a support shaft, 5 is a printing member, and 0 and O' are the centers of the connecting portions of each drive element with the movable body. 2 driving elements 3wA driving element Fig. 1 is an explanatory diagram of the principle of the present invention.

Claims (1)

[Scope of Claims] A movable body (1) that is rotatably supported on a support shaft and has a printing member (5) at its tip; and a movable body (1) that is connected to the movable body (1) and is displaced when energized. (1) in the printing direction, a pair of the drive elements are provided facing the movable body (1), and each of the drive elements (2, 3) has the movable body ( 1), the support shaft (4
) is arranged.