JPH01228182A - Piezoelectric element connecting structure - Google Patents

Abstract

PURPOSE:To enable the common connection of electrodes of piezoelectric elements easily and reliably by a method wherein a flexible printed board provided with through-holes is used, where the through-holes are arranged at the interval corresponding to the arrangement pitch of the piezoelectric elements and are connected with electrode patterns respectively. CONSTITUTION:A conductive pattern 21' is provided on an upside of a flexible printed board 21, and moreover through-holes 25 are provided at a pitch nearly equal to the arrangement pitch of piezoelectric elements 1-10. Therefore, after the piezoelectric elements 1-10 are arranged at the ends of boards 23 and 24 and fixed, the through-holes 25 of the board 21 can be successively soldered to the electrodes formed on the upper face of the piezoelectric elements 1-5, and the through-holes 25 at the end can be soldered to a common electrode pattern 25' of the printed board 23, and the piezoelectric elements 6-10 on the printed board 24 side can be connected in a similar way as of the elements 1-5 through a flexible printed board 22. By these processes, the electrodes of the piezoelectric elements 1-10 can be connected in common easily and assuredly.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a piezo element connection structure, and particularly to a piezo element connection structure in which a plurality of piezo elements are fixed on a printed circuit board and predetermined electrodes of each piezo element are commonly connected. It's about structure.

[Prior Art] Conventionally, a plurality of tactile needles are arranged in a matrix and used as a device for blind or visually impaired people to identify and read characters such as kana, alphabets, and kanji. The 0 character pattern, which is known as a device that selects and vibrates a character pattern in the form of a dot matrix and gives tactile stimulation to fingertips, etc., can be created with a character generator or the like, or can be read with an optical reader. It can be anything.

In this type of device, a piezo bimorph element is used as a vibration source for vibrating the tactile needle.

FIG. 3 shows the structure of a driving section of a tactile needle of a conventional tactile stimulation device.

In the figure, reference numerals 61 to 70 indicate tactile needles arranged in a matrix, which are attached at almost right angles to the tips of striped piezo bimorph elements (hereinafter simply referred to as piezo elements) 51 to 60, respectively. ~60
It vibrates in the vertical direction by driving the . Tactile needle 61
The tips of ~70 are arranged in a matrix so as to be lined up on a plane on an output surface (not shown).

Each piezo element has one end fixed to a drive electrode at the end of the same printed circuit board 73, 74, etc. for each row or column of the matrix, and receives and receives a drive signal.

On the other hand, the common electrodes on the top surfaces of the piezo elements 51 to 60 are commonly connected by jumper wires 71, 72, . . . . Jumper wires 71 and 72 connect the piezo elements 51 to 60 to the printed circuit board 7.
3. After fixing to 74, solder 7 in order from the piezo element at the end.
It is soldered by 5.

[Issue 8 to be solved by the invention] However, in the above conventional configuration, the jumper wire has a diameter of 0.2
Since it is a very thin and light material with a diameter of about mm, it is necessary to use tweezers to solder it, which poses the problem of very poor workability.

Furthermore, during soldering, the amount of solder is often inconsistent during work, and sometimes the solder 88 of adjacent piezo elements bond to each other, as shown in Figure 4, which can adversely affect the vibration characteristics of the piezo elements. be.

Furthermore, as shown in FIG. 5, the solders 89 of adjacent piezo elements may bond to each other and reach the intermediate electrodes 90, 90 of the piezo elements 51, 52, resulting in a short circuit between the piezo elements. Note that FIGS. 4 and 5 illustrate the structure on the printed circuit board 73 side of FIG. 3.

For these reasons, it has been extremely difficult to manufacture a tactile needle drive unit of uniform quality at a high yield and at low cost.

The object of the present invention is to solve the following problems, improve workability,
The purpose is to enable the piezo element to be fixed to the substrate-L with a high yield.

[Means for Solving the Problems] In order to solve the above problems, the present invention provides a piezo element connection structure in which a plurality of piezo elements are fixed on a printed circuit board and predetermined electrodes of each piezo element are commonly connected. In this method, using a flexible printed circuit board having through holes provided at intervals corresponding to an arrangement pitch of the piezo elements on the printed circuit board and connected to each other by an electrode pattern, the through hole portion is connected to the predetermined electrode. Accordingly, a configuration in which the predetermined electrodes are commonly connected was adopted.

[Function] According to the above configuration, the electrodes of the piezo elements can be easily and reliably connected in common through the through holes provided at fixed positions.

[Example] Hereinafter, the present invention will be described in detail based on the example shown in the drawings.

FIG. 1 shows the structure of a tactile needle drive section of a tactile stimulation device according to a first embodiment of the present invention.

In the figure, numerals 1 to 10 are piezo elements, numerals 11 to 20
is assembled in the same manner as before with a tactile needle, and the printed circuit board 23
．． They are arranged and fixed at the ends of 24.

In this embodiment, the common electrodes of the piezo elements 1-10 are connected by flexible printed circuit boards 21 and 22. Since the flexible printed circuit board 22 on the board 24 side has the same structure as the flexible printed circuit board 21, the structure on the flexible printed circuit board 21 side will be shown below.

The flexible printed circuit board 21 is in the form of a stripe, and a conductive pattern 21' is provided on its upper surface as shown by diagonal lines.

Furthermore, through holes 25 are provided in the flexible printed circuit board 21 at a pitch approximately equal to the array pitch of 2,000 pixels of the piezo elements 1-10. The through hole 25 connects common electrode patterns 25', 25' at both ends of the printed circuit board 23.
It is also located at The through hole 25 is configured to connect the land portion on the back side of the flexible printed circuit board 21 and the pattern on the front side.

The conductive pattern 421' indicated by diagonal lines is the through hole 2.
All of the upper surface portions except 5 are covered with a resist layer.

According to the above configuration, after the piezo elements 1 to 10 are arranged and fixed at the ends of the printed circuit board 23 and 24 as in the conventional case, the through holes 25 of the flexible printed circuit board 21 are sequentially connected to the electrodes on the upper surface of the piezo elements 1 to 5 by soldering 49. The common electrodes of the piezo elements 1 to 5 can be easily connected by soldering. Also, connect the through holes 25.25 at the end of the flexible printed circuit board 21 to the printed circuit board 23.
By soldering to the common electrode patterns 25', 25', connection to the common line on the printed board 23 side can be made. The piezo element on the printed circuit board 24 side can also be connected to the flexible printed circuit board 22 in the same manner as in F.

According to the above configuration, by providing the resist layer in the portion other than the through hole 25, the common electrode can be soldered at a fixed position using the solder 49 of a substantially fixed amount, which is different from the conventional method. Piezo element adjacent to -
The solder will not join or penetrate into the intermediate electrode of the piezo element, causing a short circuit.

Therefore, it is possible to connect the common electrode of the piezo elements with improved workability, and also to manufacture good products with a high yield, thereby increasing the productivity of the device and reducing costs.

In the above, a structure in which a through hole 25 is provided passing through a flexible printed circuit board has been shown, but as shown in FIG. It has a groove-shaped through hole 48 formed of the same peach.

Even when such a flexible printed circuit board 46 is used, by soldering the groove-shaped through-hole 48 with the solder 50, the common electrode can be soldered reliably and easily in the same manner as described above, and short circuits of the elements can be prevented. It can be prevented.

Although the embodiment of the tactile stimulation stirrup has been described above, it goes without saying that the same configuration can be applied to devices using various piezo elements.

[Effects of the Invention] As is clear from below-L, according to the present invention, in the piezo element connection structure in which a plurality of piezo elements are fixed to the printed circuit board -F and predetermined electrodes of each piezo element are commonly connected, By using a flexible printed circuit board having through holes provided at intervals corresponding to the arrangement pitch of the piezo elements on the printed circuit board-F and connected to each other by electrode patterns, and connecting the through hole portions to the predetermined electrodes. Since a configuration is adopted in which the predetermined electrodes are commonly connected, the electrodes of the piezo elements can be easily and reliably commonly connected through the through holes provided at the foot positions, and good products can be manufactured with a high yield. This has the excellent effect of increasing the productivity and reducing costs of devices that adopt the same structure.

[Brief Description of the Drawings] Figures 1 and 2 are perspective views showing different connection structures for piezo elements according to the present invention, Figure 3 is a perspective view showing a conventional connection structure for piezo elements, and Figure 4 3 is a perspective view showing the problems of the conventional structure shown in FIG. 3, and FIG. 5 is a sectional view showing the problems of the conventional structure shown in FIG. 1 to 10... Piezo elements 11 to 20... Tactile needle 21.22... Flexible printed circuit board 23.24
...Printed circuit board 25.48...Through hole 49.50...Solder

Claims (1)

[Claims] (1) In a piezo element connection structure in which a plurality of piezo elements are fixed on a printed circuit board and predetermined electrodes of each piezo element are commonly connected, the piezo elements are arranged at intervals corresponding to the arrangement pitch of the piezo elements on the printed circuit board. A connection structure for a piezo element, characterized in that the predetermined electrodes are commonly connected by using a flexible printed circuit board having through holes connected by electrode patterns, and by connecting the through hole portions to the predetermined electrodes.