JPH04164377A - Structure for fitting substrate of laminated piezoelectric actuator - Google Patents

Abstract

PURPOSE:To easily fit and remove a laminated piezo-electric actuator to and from a substrate by holding a piezo-electric element main body formed to a quadrangular prism between two platy electrodes composed of a pair of conductive spring members. CONSTITUTION:Two platy electrodes 8 composed of a pair of conductive spring members are conductively joined in parallel with each other to the upper surface of a substrate 7 provided with a pattern 6 for applying a voltage to a laminated piezo-electric actuator 10 having a piezo-electric element main body 4 of a quadrangular prism constituted of an ordinary layer 1 composed of a piezo-electric ceramic plate, double layer 2, and dummy layer 3 having no piezo-electric property and external electrodes 5 in such a state that the electrodes 8 are faced to each other. The two platy electrodes 8 are brought into contact with the two exposed external electrodes 5 and, because of the spring forces of the electrodes 8, the electrodes 8 do not come off the electrodes 5 even when the electrodes 8 are subjected to vibrations.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a substrate mounting structure for a laminated piezoelectric actuator, and more particularly to a substrate mounting structure for a laminated piezoelectric actuator that serves as a driving source for a printing hammer or the like of a printer.

[Conventional technology]

A conventional board mounting structure of a laminated piezoelectric actuator will be explained with reference to the drawings.

FIG. 5 is a perspective view showing an example of a conventional laminated piezoelectric actuator substrate mounting structure.

In FIG. 5, a rectangular prism-shaped piezoelectric element body 4 consisting of a normal layer 1 and a double layer 2 made of piezoelectric ceramic plates and a dummy layer 3 having no piezoelectricity is perpendicular to the displacement direction of the piezoelectric element body 4. A substrate 7 having a pattern 6a for climbing the normal layer 1, which is disposed on two opposing sides and extending up to the dummy layer 3.
The lead wire 9 is passed through the through hole of a, and the wire is attached by soldering or the like.

In the conventional laminated piezoelectric actuator board mounting structure,
To replace the laminated piezoelectric actuator, connect the lead wire 9 to the board 7.
This was done by removing the solder etc. bonded to the substrate 7a and attaching the lead wire 9 of a new multilayer piezoelectric actuator to the substrate 7a.

[Problem to be solved by the invention]

The conventional board mounting structure of the laminated piezoelectric actuator described above has the drawback that the lead wire is passed through a through-hole in the board or the like and is attached to the board by soldering, or it is very difficult to attach because the lead wire has low rigidity.

In addition, when replacing a multilayer piezoelectric actuator, the solder, etc. that connects the lead wires to the board is removed, and the lead wires of a new multilayer piezoelectric actuator are attached to the board, but the drawback is that it is very time-consuming and time-consuming to remove the solder, etc. There is.

[Means to solve the problem]

The substrate mounting structure of the laminated piezoelectric actuator of the present invention is as follows:
A square prism piezoelectric element body consisting of a normal layer and a double layer made of a piezoelectric ceramic plate and a dummy layer having no piezoelectricity;
2 facing perpendicular to the displacement direction of the piezoelectric element body
a substrate having a pattern for applying a voltage to a laminated piezoelectric actuator having an external electrode extending to the dummy layer and partially or completely uncovered on the surface; two plate-shaped electrodes each made of a conductive spring member that is in contact with the pair of external electrodes on the dummy layer, the other end of which is conductively coupled to the pattern, and which are provided in parallel and opposite to each other; .

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a perspective view showing a state before a laminated piezoelectric actuator is attached to a substrate according to an embodiment of the present invention, and FIG.
The figure is a perspective view showing the state in which the laminated piezoelectric actuator is attached to the substrate in this example, FIG. 3 is a front view showing the state before the laminated piezoelectric actuator is attached to the substrate in this example, and FIG. 4 is FIG. 3 is a front view showing a state in which a laminated piezoelectric actuator is attached to a substrate in this example.

In FIG. 1 and FIG. 2, this embodiment has a square prism piezoelectric element body 4 consisting of a normal layer 1 and a double layer 2 made of piezoelectric ceramic plates and a dummy layer 3 having no piezoelectricity; A laminated piezoelectric actuator 10 having an external electrode 5 extending to the dummy layer 3 and disposed on two opposing surfaces perpendicular to the displacement direction of the piezoelectric actuator 10, which is partially or completely uncovered and exposed. Two plate electrodes 8 made of a pair of conductive spring materials are electrically bonded to face each other in parallel on a substrate 7 having a pattern 6 for applying a voltage to.

Next, the laminated piezoelectric actuator 10 in this embodiment
A method of attaching the device to the substrate 7 will be explained with reference to FIGS. 1 to 4.

When attaching the piezoelectric element body 4 of the laminated piezoelectric actuator 10 to the substrate 7, the distance A between the tips 8-a of the two plate electrodes 8 is determined by the external voltage f!, as shown in FIG. Since the distance MB between the piezoelectric actuators 5 and 5 is smaller than the distance MB between the piezoelectric actuators 5 and 5, the laminated piezoelectric actuator 10 is attached to the substrate 7 by expanding the plate electrodes 8.

As shown in FIGS. 2 and 4, the two plate electrodes 8 are in contact with the two exposed external electrodes 5,
Due to the spring force of the two plate electrodes 8, 2
The two plate electrodes 8 are never separated from the two external electrodes. Further, the plate electrode 8 is the external electrode 5 on the dummy layer 3.
Since the layered piezoelectric actuator 10 is in contact with the layered piezoelectric actuator 10, the layered piezoelectric actuator 10 can be arranged so as not to shift even if it is displaced due to expansion and contraction.

〔Effect of the invention〕

As explained above, the present invention has a rectangular prism piezoelectric element body consisting of a normal layer and a double layer made of a piezoelectric ceramic plate and a dummy layer having no piezoelectricity, and a a substrate having a pattern for applying a voltage to a multilayer piezoelectric actuator, which has external electrodes extending to the dummy layer and partially or completely uncovered on two sides thereof; By having two plate-shaped electrodes each made of a conductive spring member that is in contact with the pair of external electrodes on the dummy layer and that is conductively coupled to the pattern at the other end and is provided in parallel and opposite to each other, Since the piezoelectric actuator can be attached and removed from the board very easily, the number of man-hours required for attaching and replacing the laminated piezoelectric actuator 5 can be reduced compared to the conventional method.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing a state before a laminated piezoelectric actuator is attached to a substrate according to an embodiment of the present invention, and FIG.
The figure is a perspective view showing the state in which the laminated piezoelectric actuator is installed on the substrate in this example, FIG. 3 is a front view showing the state before the laminated piezoelectric actuator is attached to the substrate in this example, and FIG. 4 5 is a front view showing a state in which a laminated piezoelectric actuator is attached to a substrate in this embodiment, and FIG. 5 is a perspective view showing an example of a conventional laminated piezoelectric actuator substrate mounting structure. 1... Normal layer, 2... Double layer, 3... Dummy layer, 4
... Piezoelectric element body, 5... External electrode, 6, 6a...
Pattern, 7, 7a... Substrate, 8... Plate electrode, 8-a... Tip, 9... Lead wire, 10...
Laminated piezoelectric actuator.

Claims (1)

[Claims] A square prism piezoelectric element body consisting of a normal layer and a double layer made of a piezoelectric ceramic plate and a dummy layer without piezoelectricity, and a dummy layer on two opposing faces perpendicular to the displacement direction of the piezoelectric element body. a substrate having a pattern for applying a voltage to a laminated piezoelectric actuator having external electrodes that are partially or completely uncovered and extending over the dummy layer; A laminated piezoelectric actuator comprising two plate-like electrodes each made of a conductive spring member that is in contact with the external electrode and that has the other end conductively connected to the pattern and is provided in parallel and opposite to each other. Board mounting structure.