JPS58198000A - Method and apparatus for manufacturing bimorph diaphragm - Google Patents

Abstract

PURPOSE:To eliminate influence exerted to a characteristic due to an adhesive agent, by tightly adhering and coupling a piezoelectric element, at the time of reaction of polymerization or polycondensation of thermosetting resin which becomes a diaphragm. CONSTITUTION:A gel-like base material 19 of thermosetting resin is flowed, extended and formed to a gel-like thin film 20 with uniform thickness onto a container sheet 5 from a jet nozzle, is inserted, held and transferred by the container sheets 5, 22 from the upper and lower parts together with a reinforcing sheet material 21, is slightly hardened by a preheating device 24, the film thickness is adjusted by rolls 13, 14, and thereafter, a piezoelectric element 3 is supplied by one sheet each at constant interval from a piezoelectric element supplying device 26, on a table 25. Subsequently, the piezoelectric element 3 is lightly pressed against the thin film 20 by auxiliary rolls 27, 28 provided behind the table 25, and thereafter, is made to pass through a main heating device 29. By this main heating device, the thin film 20 becomes a hardened thin film 20 as a hardening reaction of polymerization or polycondensation advances, and at the same time, the piezoelectric element 3 is tightly adhered and coupled with the thin film 20. It is punched to a bimorph diaphragm 1 of a desired shape by a press device 30 in the end.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for manufacturing a bimorph diaphragm used, for example, in a piezoelectric buzzer.

In a pressure chamber buzzer, etc., an asymmetric bimorph vibrating metal 1 such as the one shown in Fig. 1 is used as the sounding body.
It consists of an ih2 and an EI: type element 3 made of ceramic or the like attached to one side of the ih2. The vibration pattern 2 and the piezoelectric element 6 are
In most cases, the sound is fixed with an adhesive such as the above, but this adhesive method has the drawback that the adhesive increases the stiffness and stiffness, and the vibration frequency shifts to the high-pitched side. Moreover, variations in the resonance frequency occur due to factors such as the amount of adhesive applied during production.

The notes are also bad. Various techniques are known for bonding separate parts to plastic films, such as thermal F6 bonding, ultrasonic bonding, and high frequency bonding, but the use of such techniques for bimorph vibration MS is The present invention was invented in consideration of the practical situation, and the % enemy is , during the polymerization and condensation polymerization reactions of thermosetting resins, F
A manufacturing apparatus and a manufacturing method according to an embodiment of the present invention, in which the tE cold element 1r is tightly coupled, will be described with reference to the drawings. A film forming apparatus [4] is a well-known apparatus,
Although there are 11 different types, in this embodiment shown as an example, a container sheet 5 such as a metal band, which is configured as shown in FIG.
14, and then horizontally transferred to the winding drum 15 at a constant speed. Above the bench 17 is a hopper 18.
is arranged, and inside this hopper 18, Evokin is placed.

・ Contains gel material (dope) of thermosetting resin such as phenol, bo1) ester, polyimide, etc.□
It is. The gel-like material 19 is cast into a gel-like thin film 20 with a predetermined width and uniform thickness onto the container sheet 5 being transferred from the jet nozzle 20 below the hopper 18 . 21 is a reinforced sorting material such as glass fiber cloth or paper, which is fed into the gel-like thin M20 via a roll 10.

The reinforced sheet material 21 is impregnated with a gel-like thin film 20, and defoaming and film thickness adjustment are performed when it passes through the rolls 11 and 12. Between the rolls 11 and 13, an upper container sheet 22 of the same material as the container 7-5 is placed over the gel-like membrane 20. The container sheet 22 is transferred from the delivery drum 23 to the roll 11.13'i (and then wound onto the take-up drum 24). The thin film 20 that has passed through the preheating device Mt24, which is then somewhat hardened by passing it through the preheating device k24, is further adjusted in film thickness by means of rolls 13.14, and the container sheets 5.22 are each wound up. Drum 16.24F (1
As it is wound up, the thin film 20 is peeled off.

In addition, the container sheets 5 and 22 may be endless pads. Thin film 2 coming out of the film forming apparatus 4
0 is passed over the table 25, and the piezoelectric elements 5 are supplied one by one at regular intervals from the Oichi element feeder ff126 arranged above the table 25.

The piezoelectric element 3 is then pressed lightly against the membrane 20' by means of auxiliary rolls 27, 28 arranged behind the table 25 and then passed into the main heating device 29. By this main heating @ 29 VC, the thin film 20 is heated to a sufficiently high temperature, whereby the hardening reactions of polymerization and condensation of the thin film 20 proceed completely, and the thin film 20 becomes a completely hardened thin film 20'. At times, the pressure 1E element 3 is tightly coupled to the membrane 20'. Thereafter, the continuous strip-shaped thin film 20' is sent to a press machine, and is formed into a bimorph IE 11 with a desired shape as shown in FIG. Punched out. The top of the bimorph diaphragm is punched and made of sulfuric material 20.
" is wound up on a scrap winding drum (not shown).

In addition, the above 1! In the embodiment, the reinforcing sheet material 21 and the preheating device 1i24 may be omitted in some cases.

According to the uninvented bimorph diaphragm manufacturing method and device described in detail above, FEi! The elements can be attached without using adhesives, and the influence of adhesives on properties can be completely eliminated.

Furthermore, distortion and deformation of m1Flfii itself can be reduced compared to other coupling methods, and there is no effect on sound quality or imaging characteristics.

Moreover, continuous production of pages is possible, resulting in excellent productivity and a significant reduction in manufacturing costs.

[Brief explanation of the drawing]

Figure 1(a) is a front view of an example of a bimorph vibrating tank;
FIG. 2B is a sectional view thereof, and FIG. 2 is a schematic structural diagram of the manufacturing apparatus of the present invention. Yu... Bimorph Shikei 2... Shake [15... Piezoelectric element 4...
Film forming device 5 Container sheet 18 Hopper 19 Gel material (thermosetting resin) 20.20
'... Thin membrane 22... Container unit 26... Pressurized nitrogen feeder 29... Main heating device 30... Press equipment Applicant Kozue Co., Ltd.]: Agent Tsutomu Mondo, patent attorney

Claims (2)

[Claims] (1) After forming a thermosetting resin gel-like material into a thin film and before causing a curing reaction by heating, a piezoelectric element is placed on one side of this gel-like thin film, and then heated. A method for producing a bimorph diaphragm, comprising: (1) causing a curing reaction in the gel-like thin film, and tightly bonding the thin plate and the piezoelectric element by the curing reaction. (2) Continuously form a thin film of thermosetting resin gel material [! A pressure 11N element feeding device that places pressure 11N elements at regular intervals on the gel-like thin film that has come out of the film forming apparatus, and a pressure 11N element feeder that places pressure 11N elements at regular intervals on top of the gel-like thin film that has come out of the film forming apparatus. Bimorph vibration characterized by comprising: a heating device through which the thin film is passed; and a press mounting device for punching out the hardened thin film that comes out of the heating device into a predetermined shape in accordance with the position of the piezoelectric element. Book manufacturing equipment.