JP4056521B2 - Manufacturing method of pushbutton switch member - Google Patents

Manufacturing method of pushbutton switch member Download PDF

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JP4056521B2
JP4056521B2 JP2004362261A JP2004362261A JP4056521B2 JP 4056521 B2 JP4056521 B2 JP 4056521B2 JP 2004362261 A JP2004362261 A JP 2004362261A JP 2004362261 A JP2004362261 A JP 2004362261A JP 4056521 B2 JP4056521 B2 JP 4056521B2
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rubber elastic
conductive rubber
elastic body
disc spring
metal disc
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JP2005129543A (en
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均 安藤
登 中藤
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Shin Etsu Polymer Co Ltd
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Description

本発明は、電子機器、携帯端末、自動車用部品に使用される押釦スイッチ用部材の製造方法に関し、詳しくはクリック感を発生させる逆椀状部を有する押釦スイッチ用部材の製造方法に関するものである。   The present invention relates to a method for manufacturing a member for a push button switch used in an electronic device, a portable terminal, and an automotive part, and more particularly to a method for manufacturing a member for a push button switch having a reverse hook-shaped portion that generates a click feeling. .

従来から、携帯端末など軽薄短小を求められる電子機器のスイッチ部には、確実なクリック感を最小厚みで得るために、金属製や樹脂製の皿バネ(逆椀状バネ部材)をクリック感発生用部材として用いた押釦スイッチ用部材が使用されている。図7は、従来から薄形携帯電話に使用されている押釦スイッチ用部材60を示している。この押釦スイッチ用部材60は、キートップ部材61と金属製皿バネ63とは別部品としてそれぞれ筐体に組み込まれている。すなわち、金属製皿バネ63は、固定基板64上に配置された接着剤付き孔あきPETシート65の孔の部分に金属製皿バネ63の逆椀状部が対応するように配置され、その上から皿バネ固定用シート66で覆われた状態に構成されて、キートップ部材61とは別体となっており、この金属製皿バネ63の上側にキートップ部材61を重ね合わせて用いるように構成されている。   Conventionally, switch parts of electronic devices that are required to be light and thin, such as mobile terminals, have a click feeling generated by a metal or resin disc spring (reverse hook-shaped spring member) in order to obtain a reliable click feeling with a minimum thickness. A pushbutton switch member used as a member is used. FIG. 7 shows a push button switch member 60 conventionally used in a thin mobile phone. The push button switch member 60 is incorporated in the casing as a separate part from the key top member 61 and the metal disc spring 63. That is, the metal disc spring 63 is arranged so that the reverse saddle-shaped portion of the metal disc spring 63 corresponds to the hole portion of the holey PET sheet 65 with adhesive arranged on the fixed substrate 64, and And is covered with a disc spring fixing sheet 66, and is separate from the key top member 61. The key top member 61 is used in an overlapping manner on the metal disc spring 63. It is configured.

この場合、組み込み時の組み込み公差や部品の持つ寸法公差により、2部品の位置ずれが発生し、キートップ部材61の底面に設けられた突起である押圧力伝達子62が金属製皿バネ63の中心部を押圧せず、クリック感の不良を発生させることがあった。   In this case, the positional deviation of the two parts occurs due to the assembling tolerance at the time of assembling and the dimensional tolerance of the parts, and the pressing force transmitter 62 which is a protrusion provided on the bottom surface of the key top member 61 is In some cases, the center portion is not pressed and a click feeling is poor.

そこで、本出願人は、特願平10−364919号にて、ドーム状の金属製皿バネを接着剤を用いて直接キートップ部材の押圧力伝達子に接着固定する組付け方法を提案して、位置ずれに対する対策を行っている(特許文献1参照)。
また、他の特許文献には、皿バネの内面に導電性ゴムが介設されたスイッチ機構が開示されている(特許文献2参照)。
下記のものがある。
In view of this, the present applicant proposed in Japanese Patent Application No. 10-364919 a method of assembling and fixing a dome-shaped metal disc spring directly to the pressing force transmitter of the key top member using an adhesive. Measures against misalignment are performed (see Patent Document 1).
Another patent document discloses a switch mechanism in which a conductive rubber is interposed on the inner surface of a disc spring (see Patent Document 2).
There are the following.

特開2000−188035号公報(明細書段落〔0007〕,図1)Japanese Unexamined Patent Publication No. 2000-188035 (paragraph [0007], FIG. 1) 実開平05−043436号のCD−ROM(明細書段落〔0019〕,図3)Japanese Utility Model Publication No. 05-043436 CD-ROM (paragraph [0019], FIG. 3)

上記提案でキートップ部材とクリック感発生用の金属製皿バネとの位置ずれは防止できるのであるが、金属製皿バネをクリック感発生用部材として使用した場合、金属製皿バネが極めて硬いため、上方から押圧した際に固定基板の接点と点接触をする特性がある。このため、部品の組み込み際に、金属製皿バネに形成された可動接点部に微細な異物の混入や付着があると、接触不良を起こすと言う問題が有った。この異物の具体例は、ガラスエポキシ製などからなる固定基板の切削時の粉体であったり、外部から進入する挨や砂状物であったりする。その大きさは、0.1mm径以下の物も多く、組み込み環境に注意を払っても肉眼で判別することが難しいため、問題の解決ができないのが現実であった。   Although the above-mentioned proposal can prevent misalignment of the key top member and the metal disc spring for generating a click feeling, the metal disc spring is extremely hard when used as a member for generating a click feeling. When pressed from above, there is a characteristic of making point contact with the contact of the fixed substrate. For this reason, there has been a problem in that, when a component is assembled, if there is a minute foreign matter mixed in or attached to the movable contact portion formed on the metal disc spring, contact failure occurs. Specific examples of the foreign matter include powder at the time of cutting a fixed substrate made of glass epoxy or the like, or dust or sand that enters from the outside. In many cases, the size is 0.1 mm or less, and even if attention is paid to the installation environment, it is difficult to determine with the naked eye.

このため、最近では、図8に示すように、導電性接点67をポリエステルシート65に印刷し、更にポリエステルシート65とスペーサー68とを一体化し固定基板64上に粘着フィルムで固定して、上方にキートップ部材61を配置する事例や、押釦スイッチに要求されるクリック感を犠牲にして、金属製皿バネ内面や固定基板側に繊維組織を含む異方性導電弾性体シートを追加組み込む例も見られるようになっている。   Therefore, recently, as shown in FIG. 8, the conductive contact 67 is printed on the polyester sheet 65, and the polyester sheet 65 and the spacer 68 are integrated and fixed on the fixing substrate 64 with an adhesive film. See examples of arranging the key top member 61 and examples of additionally incorporating an anisotropic conductive elastic sheet including a fiber structure on the inner surface of the metal disc spring or the fixed substrate side at the expense of the click feeling required for the pushbutton switch. It is supposed to be.

いずれにしても、組み込み工数が増加することや、押釦スイッチとしての入力認識機能(クリック感)が減少すること、さらに部品の薄形化に対し悪影響を及ぼすなど、押釦スイッチ用部材としては不十分であった。   In any case, it is not enough as a pushbutton switch member because it increases the number of assembly steps, reduces the input recognition function (click feeling) as a pushbutton switch, and adversely affects the thinning of parts. Met.

本発明は、薄形軽量で、かつ良好なクリック感を損なわず、微少異物による導通不良の発生しにくい逆椀状部材を用いた押釦スイッチ用部材の製造方法を提供することを課題としている。   An object of the present invention is to provide a method for manufacturing a member for a pushbutton switch using a reverse saddle-shaped member that is thin and lightweight, does not impair a good click feeling, and does not easily cause poor conduction due to minute foreign matter.

本発明は、上記課題を解決するためなされ、請求項1に記載の押釦スイッチ用部材の製造方法は、キートップ部底面より下方に突設した押圧力伝達子の先端部に、押圧の際にその変形によりクリック感を発生させる逆椀状バネ部材が接着剤により接着一体化された押釦スイッチ用部材の製造方法であって、
先ず前記逆椀状バネ部材の内面中央部に未硬化導電性ゴム弾性体を供給し、
先端部が前記逆椀状バネ部材の曲面と同一曲面の略凸状に形成され、かつその表面に1つ以上の微細突起を有する治具を用いて、その先端部を前記逆椀状バネ部材の内面に嵌合させて所定の圧力で押圧し、前記未硬化導電性ゴム弾性体を硬化させ、該逆椀状バネ部材の内面所定範囲に導電性ゴム弾性体層を形成し、
続いて前記押圧力伝達子の先端部に接着剤を塗布して前記逆椀状バネ部材の頂点を接着するようにしたことを特徴としている。
The present invention has been made to solve the above-mentioned problems, and the manufacturing method of the member for a push button switch according to claim 1 is characterized in that the tip of the pressing force transmitter projecting downward from the bottom surface of the key top portion is pressed. A method of manufacturing a member for a push button switch in which a reverse saddle-shaped spring member that generates a click feeling by deformation thereof is bonded and integrated with an adhesive,
First, an uncured conductive rubber elastic body is supplied to the center of the inner surface of the reverse saddle spring member,
The tip portion is formed into a substantially convex shape having the same curved surface as the curved surface of the reverse saddle-shaped spring member, and the tip portion is made to have the reverse saddle-like spring member using one or more fine protrusions on the surface. And is pressed with a predetermined pressure to cure the uncured conductive rubber elastic body, to form a conductive rubber elastic body layer in a predetermined range on the inner surface of the reverse saddle-shaped spring member,
Subsequently, an adhesive is applied to the tip of the pressing force transmitter to bond the apex of the reverse saddle spring member.

また、請求項2に記載の発明は、前記導電性ゴム弾性体層が、前記逆椀状バネ部材の中心部を中心にして、全面にわたり所定の厚さで形成されていることを特徴とする請求項1記載の押釦スイッチ用部材の製造方法である。   The invention according to claim 2 is characterized in that the conductive rubber elastic body layer is formed with a predetermined thickness over the entire surface centering on a central portion of the reverse saddle-shaped spring member. It is a manufacturing method of the member for pushbutton switches of Claim 1.

本発明に係る押釦スイッチ用部材の製造方法によれば、スイッチ構造が単純化され、導電性ゴム弾性体層が均一に付与され、スイッチ構造が薄形でかつ軽量なのに、良好なクリック感を損なわず、微少異物による導通不良の発生しにくい押釦スイッチ用部材の製造方法を提供することができる効果を有する。   According to the method for manufacturing a member for a pushbutton switch according to the present invention, the switch structure is simplified, the conductive rubber elastic body layer is uniformly applied, and the switch structure is thin and lightweight, but the click feeling is impaired. In addition, there is an effect that it is possible to provide a method for manufacturing a member for a push button switch in which a conduction failure due to a minute foreign matter is unlikely to occur.

以下、図面を参照して、本発明に係る押釦スイッチ用部材の製造方法について、先ず関連するスイッチ構造を第1の実施形態として説明する。図1は、本発明に係る押釦スイッチ用部材の第1の実施形態を示し、(a)は縦断面図、(b)は底面図である。この押釦スイッチ用部材10は、図に示すように、キートップ部11を有しており、該キートップ部11底面より下方に設けられた押圧力伝達子12の先端部には、押圧の際にその変形によりクリック感を発生させる金属製皿バネ(逆椀状バネ部材)13が導電接着剤14により接着されている。また、金属製皿バネ13の内面中央部の所定範囲、すなわち直径でいうと、金属製皿バネ13直径の少なくとも8%、好ましくはほぼ全面にわたって導電接着剤により構成された厚さ0.037〜0.15mmの導電性ゴム弾性体層15が形成されている。   Hereinafter, with reference to the drawings, a related switch structure will be described as a first embodiment of a method for manufacturing a pushbutton switch member according to the present invention. 1A and 1B show a first embodiment of a push button switch member according to the present invention, in which FIG. 1A is a longitudinal sectional view and FIG. 1B is a bottom view. As shown in the drawing, the push button switch member 10 has a key top portion 11, and the tip of the pressing force transmitter 12 provided below the bottom surface of the key top portion 11 is not pressed. Further, a metal disc spring (reverse hook-like spring member) 13 that generates a click feeling due to the deformation is bonded by a conductive adhesive 14. Further, a predetermined range of the inner central portion of the metal disc spring 13, that is, in terms of diameter, at least 8% of the diameter of the metal disc spring 13, and preferably a thickness of 0.037˜ A 0.15 mm conductive rubber elastic body layer 15 is formed.

この金属製皿バネ13には、その中心部に金属製皿バネ13直径の5%〜20%径の貫通孔13aが設けられており、金属製皿バネ13の内面に形成された導電性ゴム弾性体層15と押圧力伝達子12に塗布された導電性接着剤14とは、貫通孔13aを介して連通している。これは、金属製皿バネ13を押圧力伝達子12に接着する際に生じさせたものである。   The metal disc spring 13 is provided with a through hole 13 a having a diameter of 5% to 20% of the diameter of the metal disc spring 13 at the center thereof, and a conductive rubber formed on the inner surface of the metal disc spring 13. The elastic body layer 15 and the conductive adhesive 14 applied to the pressing force transmitter 12 communicate with each other through the through hole 13a. This is generated when the metal disc spring 13 is bonded to the pressing force transmitter 12.

この製造方法について説明する。先ず、押圧力伝達子12の先端部に、シリコーン系ゴム弾性体に導電性粒子を配合した導電性接着剤14を塗布する。次に、この先端部に、金属製皿バネ13の頂点を位置決めして当接する。続いて、図4に示すような、先端部40aが金属製皿バネ13のドーム状の曲面と同一曲面の略凸状に形成され、かつ表面に直径が0.2mm程の複数の、好ましくは3点(図示した数)ないしは4点の微細突起41を有する治具40の先端部40aを、金属製皿バネ13の内面に嵌合させて、所定の圧力で押圧する。これにより、押圧力伝達子12の先端部に塗布された導電性接着剤14の一部が、金属製皿バネ13の中心部の貫通孔13aから内面に流出して導電性ゴム弾性体層15として形成される。   This manufacturing method will be described. First, a conductive adhesive 14 in which conductive particles are blended with a silicone rubber elastic body is applied to the tip of the pressing force transmitter 12. Next, the apex of the metal disc spring 13 is positioned and brought into contact with the tip. Subsequently, as shown in FIG. 4, the tip 40 a is formed in a substantially convex shape having the same curved surface as the dome-shaped curved surface of the metal disc spring 13, and a plurality of, preferably 0.2 mm in diameter on the surface, preferably A tip 40a of a jig 40 having three (number shown) or four fine projections 41 is fitted to the inner surface of the metal disc spring 13 and pressed with a predetermined pressure. As a result, a part of the conductive adhesive 14 applied to the distal end portion of the pressing force transmitter 12 flows out from the through hole 13a in the central portion of the metal disc spring 13 to the inner surface, and the conductive rubber elastic layer 15 Formed as.

なお、治具40はアルミニウム又はSUSで構成され、先端部40a及びその近傍の表面にはテフロンコートが施されている。また、金属製皿バネ13を押圧する圧力は、500grで、その時の温度は100℃、押圧時間は30secとしている。微細突起41の高さtを例えば0.04mmに設定した場合、導電性ゴム弾性体層15の厚さも0.04mm(40μm)に形成される。細突起41の高さtを、0.037〜0.15mmの範囲に設定すれば、導電性ゴム弾性体層15の厚さも0.037〜0.15mmの範囲にすることができる。この場合、微細突起41を設ける場所は、治具40の先端部の中央部分以外とする。なお、微細突起41の高さtの設定は、厳密には導電性ゴム弾性体層15の熱硬化に伴う収縮を考慮して行うことになる。なお、導電性ゴム弾性体層15の厚さを0.037〜0.15mmの範囲にした理由については後述する。   The jig 40 is made of aluminum or SUS, and a Teflon coat is applied to the front end portion 40a and the surface in the vicinity thereof. The pressure for pressing the metal disc spring 13 is 500 gr, the temperature at that time is 100 ° C., and the pressing time is 30 sec. When the height t of the fine protrusions 41 is set to 0.04 mm, for example, the thickness of the conductive rubber elastic body layer 15 is also formed to 0.04 mm (40 μm). If the height t of the fine protrusion 41 is set in the range of 0.037 to 0.15 mm, the thickness of the conductive rubber elastic body layer 15 can also be set in the range of 0.037 to 0.15 mm. In this case, the place where the fine protrusion 41 is provided is other than the central portion of the tip of the jig 40. Strictly speaking, the setting of the height t of the fine protrusion 41 is performed in consideration of the shrinkage associated with the thermosetting of the conductive rubber elastic body layer 15. The reason why the thickness of the conductive rubber elastic layer 15 is in the range of 0.037 to 0.15 mm will be described later.

次に、本発明の押釦スイッチ用部材の製造方法について、先ずそのスイッチ構造を示し、第2の実施形態として説明する。図2は、第2の実施形態を示し、(a)は縦断面図、(b)は底面図である。この押釦スイッチ用部材20は、図に示すように、キートップ部21を有しており、該キートップ部21底面に突設された押圧力伝達子22の先端部には、押圧の際にその変形によりクリック感を発生させる金属製皿バネ(逆椀状バネ部材)23が接着剤24により接着されている。また、金属製皿バネ23の内面(内面)中央部の所定範囲、すなわち直径でいうと、金属製皿バネ23直径の少なくとも8%以上の範囲に厚さ0.037mm〜0.15mmの導電性ゴム弾性体層25が形成されている。この押釦スイッチ用部材20が、第1の実施形態と異なる部分は、金属製皿バネ23の中心部に貫通孔が設けられていない点である。   Next, the manufacturing method of the member for a pushbutton switch of the present invention will be described as a second embodiment by first showing the switch structure. FIG. 2 shows a second embodiment, where (a) is a longitudinal sectional view and (b) is a bottom view. As shown in the figure, the push button switch member 20 has a key top portion 21, and the distal end portion of the pressing force transmitter 22 projecting from the bottom surface of the key top portion 21 is pressed. A metal disc spring (reverse hook-shaped spring member) 23 that generates a click feeling due to the deformation is bonded by an adhesive 24. In addition, a predetermined range of the central portion of the inner surface (inner surface) of the metal disc spring 23, that is, a diameter of 0.037 mm to 0.15 mm in the range of at least 8% of the diameter of the metal disc spring 23. A rubber elastic body layer 25 is formed. This push button switch member 20 is different from the first embodiment in that a through hole is not provided in the central portion of the metal disc spring 23.

本発明の実施形態の製造方法について説明する。先ず、金属製皿バネ23の内面中央に液体状の導電性ゴム弾性体を供給し、さらに続いて、図5に示すような、先端部50aが金属製皿バネ23のドーム状の曲面と同一曲面の凸状に形成され、かつ表面に微細突起51を有する治具50を用いて、その先端部50aを、金属製皿バネ23の内面に嵌合させて、所定の圧力で押圧する。これにより、金属製皿バネ23の内面所定範囲に導電性ゴム弾性体層25が形成される。次に、押圧力伝達子22の先端部に、接着剤24を塗布し、金属製皿バネ23の頂点を位置決めして接着する。この場合の治具50も、アルミニウム又はSUSで構成され、先端部50a及びその近傍の表面にはテフロンコートが施されている。また、金属製皿バネ23を押圧する圧力は、500grで、その時の温度は100℃、押圧時間は30secとしている。この場合も、微細突起41の高さtを例えば0.04mmに設定した場合、導電性ゴム弾性体層15の厚さも0.04mm(40μm)に形成される。細突起41の高さtを、0.037〜0.15mmの範囲に設定すれば、導電性ゴム弾性体層15の厚さも0.037〜0.15mmの範囲にすることができる。   A manufacturing method according to an embodiment of the present invention will be described. First, a liquid conductive rubber elastic body is supplied to the center of the inner surface of the metal disc spring 23, and then the tip 50a is the same as the dome-shaped curved surface of the metal disc spring 23 as shown in FIG. Using a jig 50 which is formed in a curved convex shape and has fine protrusions 51 on the surface, the tip 50a is fitted to the inner surface of the metal disc spring 23 and pressed with a predetermined pressure. Thereby, the conductive rubber elastic body layer 25 is formed in a predetermined range on the inner surface of the metal disc spring 23. Next, an adhesive 24 is applied to the tip of the pressing force transmitter 22, and the apex of the metal disc spring 23 is positioned and bonded. The jig 50 in this case is also made of aluminum or SUS, and the tip portion 50a and the surface in the vicinity thereof are coated with Teflon. The pressure for pressing the metal disc spring 23 is 500 gr, the temperature at that time is 100 ° C., and the pressing time is 30 sec. Also in this case, when the height t of the fine protrusion 41 is set to 0.04 mm, for example, the thickness of the conductive rubber elastic body layer 15 is also formed to 0.04 mm (40 μm). If the height t of the fine protrusion 41 is set in the range of 0.037 to 0.15 mm, the thickness of the conductive rubber elastic body layer 15 can also be set in the range of 0.037 to 0.15 mm.

第2の実施形態の押釦スイッチ用部材20では、金属製皿バネ23の内面に形成した導電性ゴム弾性体層25の範囲は、図2に示すように、金属製皿バネ23の中心部の一定範囲(金属製皿バネ23直径の少なくとも8%以上)であるが、供給する導電性ゴム弾性体の量を増やして、図3に示すように、内面全範囲に導電性ゴム弾性体層25を形成させるようにしてもよい。このようにすると、キートップ部21を押圧して、金属製皿バネ23を変形させると、金属製皿バネ23の裾部が当接している固定基板の固定接点面を摺動して、わずかに傷を生じさせることもあるが、このように金属製皿バネ23の内面全面にわたって導電性ゴム弾性体層25が形成されていると、導電性ゴム弾性体層25自体が固定接点面に当接摺動するので、傷が付きにくい。   In the pushbutton switch member 20 of the second embodiment, the range of the conductive rubber elastic body layer 25 formed on the inner surface of the metal disc spring 23 is the center of the metal disc spring 23 as shown in FIG. Although it is in a certain range (at least 8% or more of the diameter of the metal disc spring 23), the amount of the conductive rubber elastic body to be supplied is increased, and as shown in FIG. May be formed. In this way, when the key top portion 21 is pressed to deform the metal disc spring 23, the fixed contact surface of the fixed substrate with which the hem portion of the metal disc spring 23 abuts is slid slightly. If the conductive rubber elastic body layer 25 is formed over the entire inner surface of the metal disc spring 23 in this way, the conductive rubber elastic body layer 25 itself contacts the fixed contact surface. Because it slides in close contact, it is hard to be damaged.

金属製皿バネ13(23)の表面に導電性ゴム弾性体を付与するには、印刷、塗装、転写などの技術手法が考えられるが、目視確認できない異物の大きさを0.1mm以下として、この異物が該導電性ゴム弾性体層15(25)に確実に潜り込み固定基板との導通が取れる厚みが必要であること、また、金属製皿バネ13(23)の基本要求特性であるクリック感を確保しながら、荷重値180grから280grを確保し、しかも異物に対し効果を示すこと、さらに導電性ゴム弾性体は、金属製皿バネ13の逆椀状曲面に対し均一に付与されていることが要求される。   In order to give the conductive rubber elastic body to the surface of the metal disc spring 13 (23), technical techniques such as printing, painting, and transfer are conceivable, but the size of the foreign matter that cannot be visually confirmed is 0.1 mm or less. The foreign material must have a thickness that allows it to surely sink into the conductive rubber elastic layer 15 (25) and to be electrically connected to the fixed substrate, and the click feeling that is a basic required characteristic of the metal disc spring 13 (23). While ensuring a load value of 180 gr to 280 gr and exhibiting an effect on foreign matters, and further, the conductive rubber elastic body is uniformly applied to the inverted saddle-shaped curved surface of the metal disc spring 13 Is required.

次に、検証した結果であるが、0.1mm以下の異物に対し導通を損なわない導電性ゴム弾性体15(25)の厚みは、0.037mmから0.05mmあればよいことが判明し、好ましくは0.04mmでよいことがわかった。なお、前提である0.1mm以下の大きさの異物に対し電気的導通を損なわない範囲とした場合は、0.037mm以上であれば特に厚みは問わないが、厚みを厚くすれば、それだけ金属製皿バネのクリック感を損なうこととなる。そこで、上述のように厚みを0.04mmとするのが好ましい。   Next, as a result of verification, it has been found that the thickness of the conductive rubber elastic body 15 (25) that does not impair conduction with respect to a foreign object of 0.1 mm or less may be 0.037 mm to 0.05 mm. It has been found that 0.04 mm is preferable. In addition, when it is set as the range which does not impair electrical conduction with respect to the foreign material having a size of 0.1 mm or less, which is a premise, the thickness is not particularly limited as long as it is 0.037 mm or more. This will impair the click feeling of the disc spring. Therefore, the thickness is preferably 0.04 mm as described above.

次に、導電性ゴム弾性体15(25)の厚みを0.04mmとして、金属製皿バネ13(23)の直径を3,4,5mmと変え、クリック感を損なわないドーム状部の高さについて検証した結果を表1に記す。   Next, the thickness of the conductive rubber elastic body 15 (25) is set to 0.04 mm, the diameter of the metal disc spring 13 (23) is changed to 3, 4, and 5 mm, and the height of the dome-shaped portion that does not impair the click feeling. Table 1 shows the results of the verification.

Figure 0004056521
Figure 0004056521

表1から、逆椀状部の高さは0.19mm〜0.35mmで実現可能で、好ましくは最も良好なクリック感を示したのは0.22mmであることがわかった。なお、クリック感について説明すると、キートップ部を押し下げていくと、図6に示すように、はじめはストローク変化とともに荷重は徐々に増加して行くが、所定のストロークポイントS1に至り、逆椀状部が下方向に急激に反転変形する。逆椀状部が下方向に急激に反転変形した直後は、ストロークが増加しても荷重はかえって低下する。さらにストロークS2に至り、逆椀状部に設けられた可動接点が下方に設けられた固定接点に接触するようになると、逆椀状部の変形が終わり、その後にストロークを増加させると、格別の変形を伴わずに荷重だけが急激に増加する。なお、クリック感の良好性の指標といわれているクリック率は、 (F1−F2)/F1×100(%)
(但し、F1:ストロークS1のときの荷重、F2:ストロークS2のときの荷重)
であらわされる。ここで、良好なクリック感とは上記式の数値が30%以上である場合とした。
From Table 1, it can be seen that the height of the reverse saddle-shaped portion can be realized at 0.19 mm to 0.35 mm, and preferably 0.22 mm that showed the best click feeling. The click feeling will be described. When the key top portion is pushed down, as shown in FIG. 6, the load gradually increases with the stroke change, but reaches a predetermined stroke point S1, and has a reverse saddle shape. The part suddenly reverses and deforms downward. Immediately after the reverse saddle-shaped portion suddenly reversely deforms downward, the load is reduced even if the stroke increases. Further, when the stroke S2 is reached and the movable contact provided in the reverse saddle-shaped portion comes into contact with the fixed contact provided below, the deformation of the reverse saddle-shaped portion ends, and when the stroke is subsequently increased, Only the load increases rapidly without deformation. The click rate, which is said to be an indicator of good click feeling, is (F1-F2) / F1 × 100 (%)
(However, F1: Load at stroke S1, F2: Load at stroke S2)
It is expressed. Here, the good click feeling is defined as a case where the numerical value of the above formula is 30% or more.

以上のように、この実施形態では、スイッチ用装置における最大荷重要求の一般的値である180grから280grの値で、かつ金属製皿バネ径4mmから6mmの範囲での検証をしたが、金属製皿バネ径6mm以上、最大荷重280gr以上の場合は、金属製皿バネの内面に設けられる導電性ゴム弾性体の厚みは、クリック感が得られるドーム状部高さの変化と共に増すことができる。その場合、必要に応じて、治具40,50の微細突起の高さtを0.037〜0.15mmに変えて、導電性ゴム弾性体層15の厚さを0.037mm〜0.15mmにすればよい。   As described above, in this embodiment, verification was performed in the range of 180 to 280 gr, which is a general value of the maximum load requirement in the switch device, and in the range of the metal disc spring diameter from 4 mm to 6 mm. When the disc spring diameter is 6 mm or more and the maximum load is 280 gr or more, the thickness of the conductive rubber elastic body provided on the inner surface of the metal disc spring can be increased with a change in the height of the dome-shaped portion where a click feeling can be obtained. In that case, if necessary, the height t of the fine protrusions of the jigs 40 and 50 is changed to 0.037 to 0.15 mm, and the thickness of the conductive rubber elastic body layer 15 is set to 0.037 mm to 0.15 mm. You can do it.

次に、導電性ゴム弾性体層15(25)の厚みを0.04mmとし、異物の径を0.04mm〜0.150mmと変えて、キートップ部材11(21)を押し込み、金属製皿バネのみの場合と比較して、オンするまでの時間を検証したものを表2に示す。   Next, the thickness of the conductive rubber elastic layer 15 (25) is set to 0.04 mm, the diameter of the foreign matter is changed from 0.04 mm to 0.150 mm, the key top member 11 (21) is pushed in, and the metal disc spring is pressed. Table 2 shows the results of verifying the time to turn on compared to the case of only the case.

Figure 0004056521
Figure 0004056521

表2からわかるように、導電性ゴム弾性体層15(25)を設けた場合に比べ、金属製皿バネ13(23)のみの場合は反応時間がかかり、かつ異物の径が0.09mmでは接点をオンすることができなかった。導電性ゴム弾性体層15(25)を設けた場合は、異物の径が0.09mmでも接点はオンすることがわかった。   As can be seen from Table 2, compared to the case where the conductive rubber elastic body layer 15 (25) is provided, the reaction time is longer when only the metal disc spring 13 (23) is used, and the foreign matter diameter is 0.09 mm. The contact could not be turned on. When the conductive rubber elastic layer 15 (25) was provided, it was found that the contact point was turned on even when the diameter of the foreign material was 0.09 mm.

ところで、導電性ゴム弾性体層15(25)の厚さを0.037mm〜0.15mmの範囲とした理由を、ここで説明する。先ず、下限である0.037mmについてであるが、表2から、金属製皿バネのみの場合は、異物の径が0.09mmでは導通が得られず、異物の径が0.063mmのときにはオンするまでの時間がかかるもののオンするので、ここがほぼ限界点と考えられる。したがって、目視不能な異物の最大径を0.1mmとすると、これが導電性ゴム弾性体層15(25)の中に埋まった場合に、外部に突出する部分の高さを0.063mmにするには、導電性ゴム弾性体層15(25)の厚さを0.037mm(0.1−0.063=0.037mm)にすれば良いことがわかる。   Now, the reason why the thickness of the conductive rubber elastic layer 15 (25) is set in the range of 0.037 mm to 0.15 mm will be described here. First, regarding the lower limit of 0.037 mm, from Table 2, when only a metal disc spring is used, conduction is not obtained when the diameter of the foreign object is 0.09 mm, and on when the diameter of the foreign object is 0.063 mm. Although it takes time to do, it turns on, so this is considered to be almost the limit point. Therefore, if the maximum diameter of a foreign object that cannot be seen is 0.1 mm, the height of the portion protruding to the outside is set to 0.063 mm when this is buried in the conductive rubber elastic layer 15 (25). Indicates that the thickness of the conductive rubber elastic layer 15 (25) may be 0.037 mm (0.1−0.063 = 0.037 mm).

次に、上限である0.15mmについて説明する。導電性ゴム弾性体15(25)の厚さは、厚い方向に振れるほど異物対策の点に対しては良好な結果をもたらすが、スイッチとしての基本性能である明瞭なクリック感の発生という点では、ストロークが減少するため、好適とはいえない。一般的に、金属製皿バネは、その断面形状が略台形状の上底部になだらかな半球を乗せたような形状をしており、ストロークは0.18mmから0.7mm、多くは0.2mmから0.35mmである。この0.35mmストローク時においても、クリック感を損なわないようにするには、クリック感を損なわない最低ストローク0.2mmを差し引いて、0.35−0.2=0.15mmとなることがわかる。したがって、径が0.1mm以下の異物全てに対し効果を満たすために必要な導電性ゴム弾性体層は、0.03mm〜0.15mmということになる。なお、0.1mmを超える異物は、製造・組立工程における目視検査にて除去されうる。   Next, the upper limit of 0.15 mm will be described. As the thickness of the conductive rubber elastic body 15 (25) swings in the thicker direction, a better result is obtained in terms of measures against foreign matters, but in terms of generating a clear click feeling, which is a basic performance as a switch. Since the stroke is reduced, it is not preferable. In general, a metal Belleville spring has a cross-sectional shape in which a gentle hemisphere is placed on the upper base of a substantially trapezoidal shape, with a stroke of 0.18 mm to 0.7 mm, many 0.2 mm. To 0.35 mm. In order not to impair the click feeling even at this 0.35 mm stroke, it is understood that 0.35-0.2 = 0.15 mm is obtained by subtracting the minimum stroke of 0.2 mm that does not impair the click feeling. . Therefore, the conductive rubber elastic body layer necessary for satisfying the effect on all foreign matters having a diameter of 0.1 mm or less is 0.03 mm to 0.15 mm. In addition, the foreign material exceeding 0.1 mm can be removed by visual inspection in the manufacturing / assembly process.

次に、同様にして、接触抵抗値を測った結果を表3に記す。   Next, the results of measuring the contact resistance values are shown in Table 3.

Figure 0004056521
Figure 0004056521

表3からわかるように、金属製皿バネ13(23)のみのときの方が、抵抗値の低いことが当然の結果として現れたが、特に問題となる差ではなく、導電性ゴム弾性体層15(25)も十分接点部材として使用することができることが表示されている。導電性ゴム弾性体層15(25)の接触抵抗値としては、50Ω以下であれば問題なく、弾性率と抵抗値の関連で、所望の弾性体を選べる。
但し、導電性を上げ抵抗値を下げる事を念頭に検証した場合、導電性炭素粒子や金属粒子をゴム弾性体に過分に配合すると、物理的強度から接点寿命に支障をきたすのみならず、接点粉による接点間の短絡を引き起こす可能性もある。
ゴム弾性体原材料の材料部数の10%から45%以内が可能で、より好ましくは15%から35%の範囲とする。
As can be seen from Table 3, it is obvious that the resistance value is lower when only the metal disc spring 13 (23) is used, but this is not a particularly problematic difference. 15 (25) is also shown to be sufficient as a contact member. As a contact resistance value of the conductive rubber elastic body layer 15 (25), if it is 50Ω or less, there is no problem, and a desired elastic body can be selected in relation to the elastic modulus and the resistance value.
However, when verifying with the aim of increasing the conductivity and decreasing the resistance value, adding conductive carbon particles or metal particles to the rubber elastic body excessively will not only affect the contact life from the physical strength, but also contact points. There is also the possibility of causing a short circuit between the contacts due to powder.
It can be within 10% to 45% of the number of material parts of the rubber elastic body raw material, and more preferably within the range of 15% to 35%.

金属製皿バネは、ステンレス0.05mm厚のSUS301製を逆椀状にプレス金型にて逆椀状部径5mm、逆椀状部高さ0.26mm、最大荷重230grの逆椀状形状に成形する。
逆椀状部内面にKE−3490導電性RTV接着剤(信越化学工業製)を0.15gr供給、逆椀状部形状と同じく先端形状を加工され、テフロン処理されたアルミニウム製円筒形治具を(図5参照)100℃に加熱後、金属製皿バネ内面に500grにて30秒間加圧形成する。ここで得られた金属製皿バネを押圧力伝達子に接着固定することにより、押釦スイッチ用部材20を得た。
Stainless steel disc spring made of SUS301 with a thickness of 0.05 mm in a reverse bowl shape is formed into a reverse bowl shape with a reverse bowl shape part diameter of 5 mm, a reverse bowl part height of 0.26 mm, and a maximum load of 230 gr. Mold.
KE-3490 conductive RTV adhesive (manufactured by Shin-Etsu Chemical Co., Ltd.) is supplied to the inner surface of the reverse hook-shaped part in an amount of 0.15 gr. (See FIG. 5) After heating to 100 ° C., pressure is formed on the inner surface of the metal disc spring at 500 gr for 30 seconds. The pushbutton switch member 20 was obtained by bonding and fixing the metal disc spring obtained here to the pressing force transmitter.

金属製皿バネは、ステンレス0.05mm厚のSUS301製を逆椀状にプレス金型にて逆椀状部径5mm、逆椀状部高さ0.28mm、最大荷重250grの逆椀状部形状を成形する。この際、金属製皿バネ中央には0.7mmの貫通孔を設けておく。
押圧力伝達子と金属製皿バネを接着固定する際に使用されるシリコーン系接着剤スーパーX(セメダイン社製)に炭素系導電粒子5材料部数、銀粒子10材料部数配合し接着固定する。
その際、金属製皿バネ中心部から吐出した導電性接着剤を逆椀状形状と同じく先端形状を加工され、テフロン処理されたアルミニウム製円筒形治具を(図4参照)100℃に加熱後、金属製皿バネ内面に500grにて30秒間加圧形成することにより硬化した導電性ゴム弾性体層を付与された押釦スイッチ用部材10を得た。
The metal disc spring is made of stainless steel 0.05 mm thick made of SUS301 in a reverse saddle shape with a reverse die shape with a reverse saddle shape part diameter of 5 mm, reverse saddle shape part height of 0.28 mm, and a maximum load of 250 gr. Is molded. At this time, a 0.7 mm through hole is provided in the center of the metal disc spring.
5 parts of carbon-based conductive particles and 10 parts of silver particles are blended and fixed in a silicone-based adhesive Super X (manufactured by Cemedine Co., Ltd.) used when the pressing force transmitter and a metal disc spring are bonded and fixed.
At that time, after the conductive adhesive discharged from the center part of the metal disc spring was heated to 100 ° C. (see FIG. 4), the aluminum cylindrical jig whose tip shape was processed in the same manner as the inverted saddle-like shape and processed with Teflon Then, a member 10 for a push button switch provided with a conductive rubber elastic body layer cured by press forming at 500 gr for 30 seconds on the inner surface of the metal disc spring was obtained.

なお、上記実施形態及び実施例において、本発明にいう逆椀状部材としてSUS等による金属製皿バネ12(23)を用いているが、クリック感を得られる部材であれば金属に変わってプラスチックなども用いることができる。   In the above-described embodiment and examples, the metal disc spring 12 (23) made of SUS or the like is used as the inverted saddle-like member referred to in the present invention. Etc. can also be used.

本発明の押釦スイッチ用部材の製造方法に関係した第1の実施形態を示し、(a)は押釦スイッチ用部材の縦断面図、(b)はその底面図である。1A and 1B show a first embodiment related to a method for manufacturing a member for a push button switch according to the present invention, in which FIG. 本発明の押釦スイッチ用部材の製造方法に係わる第2の実施形態を示し、(a)は押釦スイッチ用部材の縦断面図、(b)はその底面図である。2nd Embodiment concerning the manufacturing method of the member for pushbutton switches of this invention is shown, (a) is a longitudinal cross-sectional view of the member for pushbutton switches, (b) is the bottom view. 第2の実施形態の押釦スイッチ用部材の変形例を示し、(a)はその縦断面図、(b)はその底面図である。The modification of the member for pushbutton switches of 2nd Embodiment is shown, (a) is the longitudinal cross-sectional view, (b) is the bottom view. 第1の実施形態に係る押釦スイッチ用部材を製造するときの治具及び製造方法を示し、(a)は治具の平面図、(b)は側面図、(c)は導電性ゴム弾性体層の成形方法を示す図である。The jig | tool and manufacturing method when manufacturing the member for pushbutton switches which concern on 1st Embodiment are shown, (a) is a top view of a jig | tool, (b) is a side view, (c) is a conductive rubber elastic body It is a figure which shows the shaping | molding method of a layer. 第2の実施形態に係る押釦スイッチ用部材を製造するときの治具及び製造方法を示し、(a)は治具の平面図、(b)は側面図、(c)は導電性ゴム弾性体層の成形方法を示し、(d)は金属製皿バネをキートップ部材の押圧力伝達子に接着した状態を示す図である。The jig | tool and manufacturing method when manufacturing the member for pushbutton switches concerning 2nd Embodiment are shown, (a) is a top view of a jig | tool, (b) is a side view, (c) is a conductive rubber elastic body FIG. 4D shows a layer forming method, in which (d) shows a state in which a metal disc spring is bonded to a pressing force transmitter of a key top member. 押圧荷重とストロークとの関係を示すスイッチ特性曲線である。It is a switch characteristic curve which shows the relationship between a pressing load and a stroke. 従来の押釦スイッチ用部材の縦断面図である。It is a longitudinal cross-sectional view of the conventional member for pushbutton switches. 同じく、従来の押釦スイッチ用部材の縦断面図である。Similarly, it is a longitudinal cross-sectional view of the conventional member for pushbutton switches.

符号の説明Explanation of symbols

10、20 押釦スイッチ用部材
11、21 キートップ部材
12、22 押圧力伝達子
13、23 金属製皿バネ(逆椀状バネ部材)
14 導電性接着剤
15、25 導電性ゴム弾性体層
24 接着剤
40、50 治具
41、51 微細突起
10, 20 Pushbutton switch member 11, 21 Key top member 12, 22 Pressing force transmitter 13, 23 Metal disc spring (reverse saddle spring member)
14 Conductive adhesive 15, 25 Conductive rubber elastic layer 24 Adhesive 40, 50 Jig 41, 51 Fine protrusion

Claims (2)

キートップ部底面より下方に突設した押圧力伝達子の先端部に、押圧の際にその変形によりクリック感を発生させる逆椀状バネ部材が接着剤により接着一体化された押釦スイッチ用部材の製造方法であって、
先ず前記逆椀状バネ部材の内面中央部に未硬化導電性ゴム弾性体を供給し、
先端部が前記逆椀状バネ部材の曲面と同一曲面の略凸状に形成され、かつその表面に1つ以上の微細突起を有する治具を用いて、その先端部を前記逆椀状バネ部材の内面に嵌合させて所定の圧力で押圧し、前記未硬化導電性ゴム弾性体を硬化させ、該逆椀状バネ部材の内面所定範囲に導電性ゴム弾性体層を形成し、
続いて前記押圧力伝達子の先端部に接着剤を塗布して前記逆椀状バネ部材の頂点を接着するようにしたことを特徴とする押釦スイッチ用部材の製造方法。
A pushbutton switch member in which a reverse saddle-shaped spring member that generates a click feeling due to deformation thereof is bonded and integrated with an adhesive at the tip of a pressing force transmitter projecting downward from the bottom surface of the key top portion. A manufacturing method comprising:
First, an uncured conductive rubber elastic body is supplied to the center of the inner surface of the reverse saddle spring member,
The tip portion is formed into a substantially convex shape having the same curved surface as the curved surface of the reverse saddle-shaped spring member, and the tip portion is made to have the reverse saddle-like spring member using one or more fine protrusions on the surface. And is pressed with a predetermined pressure to cure the uncured conductive rubber elastic body, to form a conductive rubber elastic body layer in a predetermined range on the inner surface of the reverse saddle-shaped spring member,
Then, the manufacturing method of the member for pushbutton switches characterized by apply | coating an adhesive agent to the front-end | tip part of the said pressing force transmission element, and adhere | attaching the vertex of the said reverse saddle-like spring member.
前記導電性ゴム弾性体層が、前記逆椀状バネ部材の中心部を中心にして、全面にわたり所定の厚さで形成されていることを特徴とする請求項1記載の押釦スイッチ用部材の製造方法。   2. The member for a push button switch according to claim 1, wherein the conductive rubber elastic body layer is formed with a predetermined thickness over the entire surface centering on a central portion of the reverse saddle-shaped spring member. Method.
JP2004362261A 2004-12-15 2004-12-15 Manufacturing method of pushbutton switch member Expired - Lifetime JP4056521B2 (en)

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JP2007234532A (en) * 2006-03-03 2007-09-13 Shin Etsu Polymer Co Ltd Key-switch member and key switch provided with the same
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