JPS6161599B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a diaphragm for an electroacoustic transducer, in which a powder of an inorganic solid material is diffused onto the surface of a diaphragm base molded from an inorganic solid material such as a thin metal plate.

Conventionally, materials that have been used as diaphragms for electroacoustic transducers such as speakers not only have a high Young's modulus, but also have high compliance, are lightweight, have appropriate rigidity, and are unaffected by temperature, humidity, etc. It is desirable that Those formed using lightweight metal materials such as aluminum, titanium, and perium; those formed from plastic such as polyester; those formed by impregnating cloth with resin and heating; and those formed from carbon fiber composite materials. There are things that have been done.

By the way, the diaphragm base 5', which is made of a lightweight metal thin plate such as titanium or aluminum, is made of boron or silicon to increase rigidity, make it chemically inert, and not be affected by temperature and humidity. The diaphragm was formed by surface treatment such as depositing an inorganic solid material such as carbon on the surface. However, since the coefficient of thermal expansion is significantly different from that of the vapor deposited layer of the inorganic solid substance surface-treated on the surface of the diaphragm base 5' after cooling, the vapor deposited layer surface-treated after cooling will crack and become unusable.

Therefore, boron was added to the surface of the diaphragm base 5', which was molded from a lightweight metal thin plate such as titanium or aluminum.
As shown in Figure 1, a method for diffusing inorganic solid substances such as silicon and carbon involves molding metals such as titanium and aluminum or inorganic solid substances such as carbon fiber into a cone-shaped or dome-shaped diaphragm shape. The outer peripheral edge 5'a of the diaphragm base 5' is placed on the mounting step 6'b formed on the outer periphery and upper surface of the jig, and housed in the sealed container 1, and then boron, silicon, Then, the inside of the sealed container 1 containing powder 3 of an inorganic solid material such as carbon is heated to diffuse the inorganic solid material such as boron onto the surface of the diaphragm base 5' to form a diaphragm.

However, in this conventional method, the outer periphery of the diaphragm base 5' is slightly elongated relative to the mounting step 6'b of the jig 6' due to heating during the diffusion of the inorganic solid substance, and furthermore, the outer periphery 5'a became wavy, warped, and other deformations occurred. Moreover, manufacturing the diaphragm by stacking the diaphragm substrates 5' and diffusing the inorganic solid substance all at once has the drawback of poor mass productivity.

The present invention has been made in view of the above-mentioned points, and its object is to provide a storage step portion in which the outer peripheral edge of a diaphragm base for diffusing an inorganic solid substance is formed on the upper surface and inner periphery of a jig. By storing the inorganic solid material in a container, the expansion of the outer periphery of the diaphragm substrate is restricted due to heating during the diffusion of the inorganic solid substance, preventing the outer periphery from waving or deforming such as warping, thereby reducing product loss. It is to provide a diaphragm with less vibration.

The outline of the present invention will be explained below in accordance with FIGS. 2 to 4 along with the apparatus used.

Reference numeral 1 denotes a sealed container made of a heat-resistant material such as alumina, and the sealed container 1 is fitted with a lid 2 that can be freely fitted and removed. The powder 3 is contained therein and heated by a heater 4 wound around the outer periphery.

First, as a first step, an annular storage step is formed on the upper surface of the jig 6 by forming the outer peripheral edge 5a of the diaphragm base 5, which is formed into a predetermined diaphragm shape such as a cone shape or a dome shape, using an inorganic solid material. 6 a and embedded in an inorganic solid material powder 3 housed in a sealed container 1 . As the inorganic solid substance forming the diaphragm base 5, materials such as titanium, aluminum, silicon, or alloys containing these as main components are used. Reference numeral 5b denotes a rib for absorbing stretch formed on the outer peripheral edge 5a of the diaphragm base 5. Although the rib 5b is formed in a roll shape in the drawing, it may be formed in a V-shape.

Next, as a second step, a heater (not shown) is heated to heat the inside of the sealed container 1 at a temperature of 800 to 1000 degrees Celsius, thereby activating the inorganic solid substance powder 3 housed inside the sealed container 1 and An inorganic solid substance is diffused onto the surface of the substrate 5. At this time, even if the diaphragm base 5 expands due to the heat during diffusion, the diaphragm base 5
Since the outer peripheral edge 5a of the jig 6 is fitted into and stored in the storage step 6a formed on the upper surface of the jig 6, the outer peripheral edge 5
Since the end portion of a is abutted against the inner peripheral wall of the storage step portion 6a, the elongation is absorbed by the ribs formed on the outer peripheral edge portion 5a, and deformation such as waving or warping of the outer peripheral edge portion 5a can be prevented.

As a third step, after cooling, the diaphragm substrate 5 is taken out from the sealed container 1 and the inorganic solid material is diffused using the male die 7 and the female die 8, and the diaphragm substrate 5 is cut from the outer peripheral edge 5a to produce a diaphragm as a finished product. Get 9.

As an embodiment of the present invention, a case will be explained in which titanium is used as the inorganic solid material for molding the diaphragm base 5 to form a dome shape, and boron is used as the inorganic solid material powder 3 housed in the sealed container 1. do. First, the outer peripheral edge 5a of the diaphragm base 5 molded into a dome shape using titanium is stored in the storage step 6a formed on the top surface of the jig 6 in the sealed container 1, and the outer peripheral edge 5a of the diaphragm base 5 is molded into a dome shape using titanium. By embedding it in boron powder and heating it at a temperature of 800 to 1000° C. for about one hour, boron is activated and diffused into the diaphragm base 5 made of titanium.
At this time, the outer peripheral edge 5a of the diaphragm base 5 is stored and placed on the upper surface of the storage step 6a formed on the upper surface of the jig 6, so the outer peripheral edge 5a abuts against the inner wall of the storage step 6a. In addition to regulating the stretching, the ribs 5b formed on the outer peripheral edge 5a can absorb the stretching and prevent deformation such as warping. Thereafter, after cooling, the diaphragm substrate 5 is cut from the sealed container 1 using a male die 7 and a female die 8 to obtain a diaphragm 9 as a finished product.

What is shown in FIG. 5 is another embodiment of the present invention, in which an outer peripheral edge 5a of the diaphragm 9 is attached to the inner periphery of the upper surface of the jig 6.
The placement and storage of the jig 6 is the same as in the previous embodiment, but by providing the fitting step 6b on the outer periphery of the lower surface of the jig 6, the fitting step 6b of the upper jig 6 can be placed and housed in the lower jig. The outer peripheral edge 5a of the lower diaphragm base 5 is inserted into the storage step 6a of the jig 6 and is held between the storage step 6a of the lower jig 6 and the insertion step 6b of the upper jig 6. The diaphragm substrate 5 is sequentially laminated in several layers in a sealed container 1 and embedded in boron powder 3, and boron is laminated on the diaphragm substrate 5 under the same conditions as in the previous embodiment. Note that the same parts in each figure are indicated by the same reference numerals.

As described above, the present invention has the outer periphery of the diaphragm substrate that diffuses the inorganic solid substance stored in the storage stage formed on the top surface of the jig and the inner periphery, thereby heating the inorganic solid substance during diffusion. This makes it possible to restrict the extension of the outer peripheral edge of the diaphragm base, thereby preventing the outer peripheral edge from waving, warping, or other deformation, thereby providing a diaphragm with less product loss.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an apparatus showing a conventional method for manufacturing a diaphragm for an electroacoustic transducer, and FIGS. 2 to 4 similarly show the process order in an embodiment of the diaphragm for an electroacoustic transducer of the present invention. 5 is a sectional view showing another embodiment of the present invention. 1... Sealed container, 3... Powder of inorganic solid substance,
4... Heater, 5a... Outer periphery, 6... Jig,
6a...Storage stage section.

Claims (1)

[Scope of Claims] 1. The outer peripheral edge of a diaphragm base formed in a predetermined diaphragm shape such as a cone shape or a dome shape using an inorganic solid substance is attached to an annular storage step formed on the top surface of a jig. The inorganic solid substance is applied to the diaphragm substrate by a first step of storing the diaphragm substrate, and heat-treating the diaphragm substrate in a powder of an inorganic solid substance different from the inorganic solid substance in a sealed container made of a heat-resistant material. A method for manufacturing a diaphragm for an electroacoustic transducer, comprising a second step of diffusing the diaphragm, and a third step of cutting the outer peripheral edge of the diaphragm base by cooling and press-molding. 2. The method of manufacturing a diaphragm for an electroacoustic transducer according to claim 1, wherein the inorganic solid material used to mold the diaphragm substrate is titanium or an alloy containing titanium as a main component. 3. Claim 1, wherein the inorganic solid substance diffused into the diaphragm substrate is boron or a powder of an inorganic solid substance containing boron as a main component.
A method for manufacturing a diaphragm for an electroacoustic transducer as described in . 4. The method for manufacturing a diaphragm for an electroacoustic transducer according to claim 1, wherein the inorganic solid substance diffused into the diaphragm substrate is silicon or a powder of an inorganic solid substance mainly composed of silicon. . 5. Manufacturing a diaphragm for an electroacoustic transducer according to claim 1, wherein the inorganic solid substance diffused into the diaphragm substrate is carbon or a powder of an inorganic solid substance containing carbon as a main component. Method. 6. The jig is made of a heat-resistant material, and has a storage step on the inner periphery of the upper surface for placing and accommodating the outer peripheral edge of the diaphragm base, and has a step on the outer periphery of the lower surface into which the upper jig is inserted. The outer peripheral edge of the lower diaphragm base is held and fixed between the storage step of the lower jig and the insertion step of the upper jig by inserting it into the storage step of the lower jig. A vibration for an electroacoustic transducer according to claim 1, characterized in that the diaphragm substrate is laminated in a sealed container via a tool, and then heat-treated to diffuse an inorganic solid substance into the diaphragm substrate. Method of manufacturing the board.