JP4558073B2

JP4558073B2 - Solder bath and heating method of solder bath

Info

Publication number: JP4558073B2
Application number: JP2008299750A
Authority: JP
Inventors: 彰高口; 敏雄宮下; 昇橋本
Original assignee: Senju Metal Industry Co Ltd
Current assignee: Senju Metal Industry Co Ltd
Priority date: 2008-11-25
Filing date: 2008-11-25
Publication date: 2010-10-06
Anticipated expiration: 2023-06-17
Also published as: JP2009061506A

Description

本発明は、はんだ槽内のはんだを加熱溶融する技術分野に関する。 The present invention relates to the technical field of heating and melting solder in a solder bath.

従来、はんだを加熱する手段としては、はんだ槽内にシーズヒーターを通す技術が知られている（例えば、特許文献１参照。）。 Conventionally, as a means for heating solder, a technique of passing a sheathed heater in a solder bath is known (see, for example, Patent Document 1).

特開２００３−１３６２３３号公報（第２頁、第７図）JP 2003-136233 A (2nd page, FIG. 7)

しかしながら、はんだ槽内のはんだはシーズヒーターによって局部的に加熱されているので、シーズヒーターの付近と離れている箇所でははんだの温度バラツキが大きく、それ故、ノズルから流出するはんだの温度バラツキが生じ、ひいてははんだ不良を招くことになった。また、シーズヒーター付近が加熱されて局部的に膨張するため、はんだ槽の寿命が短くなる。さらに、はんだ槽の熱が外面から空気中に逃げるため、運転コストが高くなった。 However, since the solder in the solder bath is locally heated by the sheathed heater, the temperature variation of the solder is large in the vicinity of the sheathed heater and away from the sheathed heater. As a result, a solder defect was caused. Further, since the vicinity of the sheathed heater is heated and locally expands, the life of the solder bath is shortened. Furthermore, since the heat of the solder bath escapes from the outer surface into the air, the operating cost is increased.

本発明は上記実情を考慮してなされたもので、はんだ槽内のはんだ温度をできる限り均一に保つと共にはんだ槽の寿命を延ばし、その上、運転コストの低下をも図ることのできるはんだ槽及びはんだ槽の加熱方法の開発を、解決しようとする課題とする。 The present invention has been made in consideration of the above circumstances, and a solder bath that can maintain the solder temperature in the solder bath as uniform as possible and extend the life of the solder bath, and can also reduce the operating cost. The development of a solder bath heating method is a problem to be solved.

本発明のうち請求項１の発明は、はんだの液面レベルよりも下側に入口が設けられると共に前記液面レベルよりも上側に出口が設けられ且つ前記入口付近にポンプが備えられるはんだ送り室を内部に有したはんだ槽の外周面のうち前記液面レベルよりも少なくとも下側全域、および前記はんだ槽の底面全域を、ステンレスからなる熱伝導板、発熱する抵抗体を埋没させたセラミックボードの順番にそれぞれ直に覆い、前記熱伝導板および前記セラミックボードを前記はんだ槽とは別体とし、前記熱伝導板を介して前記抵抗体の熱が前記はんだ槽に均一に伝わるようにしたものである。 According to the first aspect of the present invention, there is provided a solder feed chamber in which an inlet is provided below a solder liquid level, an outlet is provided above the liquid level, and a pump is provided near the inlet. Of the outer peripheral surface of the solder bath having the inside thereof, at least the entire region below the liquid level and the entire bottom surface of the solder bath are made of a heat conductive plate made of stainless steel, a ceramic board in which a heating resistor is embedded respectively directly covered in turn, the heat conduction plate and the ceramic board and separately from said solder bath, in which the heat of the resistor via the heat conducting plate is so transmitted uniformly to the solder bath is there.

また、請求項２の発明は、前記はんだ槽の外周面には支持プレートが上下に間隔をあけて設けてあり、前記熱伝導板、前記セラミックボードを前記支持プレート同士の間に配置した状態で固定してあることを特徴とする。
According to a second aspect of the present invention, a support plate is provided on the outer peripheral surface of the solder tank with an interval in the vertical direction, and the heat conducting plate and the ceramic board are arranged between the support plates. It is characterized by being fixed.

また、請求項３の発明は、請求項１又は２記載のはんだ槽を用い、前記抵抗体より発熱した熱が前記熱伝導板を介して前記はんだ槽に伝わるように、前記はんだ槽の外周面のうち前記液面レベルよりも少なくとも下側全域、および前記はんだ槽の底面全域を均一に加熱するはんだ槽の加熱方法である。 The invention of claim 3, using solder bath of claim 1 or 2, wherein, as heat generated from the resistor is transmitted to the solder bath via the thermal conductive plate, the outer peripheral surface of the solder bath a method of heating a solder bath to uniformly heat at least the lower whole, and the bottom surface the whole area of the solder bath than the liquid level of the.

はんだ槽の底面全域をステンレスからなる熱伝導板等で覆うとしてあるが、厳密に全域を覆ってあるという意味ではなく、外観的に全域を覆ってあると判断できる程度であれば良いという意味である。詳しく言えば、はんだ槽にはリブが通常付いているので、リブは必ずしも覆わなくても良い。また、リブ以外の箇所は全域隙間無く覆ってあるという意味では必ずしもなく、例えば底面にリブが付いていると、複数枚の熱伝導板で底面を覆うことになり、取り付けの際には、リブと熱伝導板の間に通常、隙間をあけるので、このような隙間部分も熱伝導板で覆われない。なお、はんだ槽の外周面を熱伝導板で覆う場合も同様である。 Although the entire bottom surface of the solder bath is covered with a heat conductive plate made of stainless steel, it does not mean that the entire area is covered strictly, but it is only necessary to be able to judge that the entire area is covered externally. is there. Specifically, since the solder bath is usually provided with ribs, the ribs do not necessarily have to be covered. In addition, it does not necessarily mean that parts other than the ribs are covered without gaps throughout the area. For example, if there are ribs on the bottom surface, the bottom surface is covered with a plurality of heat conduction plates. Since a gap is usually formed between the heat conduction plate and the heat conduction plate, such a gap is not covered with the heat conduction plate. The same applies to the case where the outer peripheral surface of the solder bath is covered with a heat conductive plate.

本発明のはんだ槽は、はんだ槽のほぼ全域を覆ったステンレスからなる熱伝導板を介して抵抗体の熱がはんだ槽に伝わるので、はんだ槽の底面及び外周面が均一に加熱されることになり、はんだ槽内のはんだ温度が従来に比べて均一となる。従って、はんだ送り室の出口から流出するはんだの温度が均一となり、良品率が向上する。また、はんだ槽全体が均一に加熱されて膨張するので、製品寿命も延びる。さらに、はんだ槽の外面を熱伝導板、セラミックボードで順に覆って熱を逃げ難くしてあるので、運転コストが低下する。 In the solder bath of the present invention, the heat of the resistor is transmitted to the solder bath via the heat conductive plate made of stainless steel covering almost the entire area of the solder bath, so that the bottom surface and the outer peripheral surface of the solder bath are uniformly heated. Thus, the solder temperature in the solder bath becomes uniform as compared with the conventional case. Therefore, the temperature of the solder flowing out from the outlet of the solder feed chamber becomes uniform, and the yield rate is improved. In addition, since the entire solder bath is uniformly heated and expanded, the product life is extended. Furthermore, since the outer surface of the solder bath is covered with a heat conductive plate and a ceramic board in order to make it difficult for heat to escape, the operating cost is reduced.

本発明のはんだ槽としての噴流型はんだ槽は、図１に示すように、上向きに開口する四角形のはんだ槽１のほぼ外面全域を熱伝導板２、断熱材付きの面ヒーター３で順番に覆い、はんだ槽１、熱伝導板２、面ヒーター３、断熱材の四層構造としたものである。 As shown in FIG. 1, the jet type solder bath as the solder bath of the present invention covers the entire outer surface of a square solder bath 1 opening upward with a heat conductive plate 2 and a surface heater 3 with a heat insulating material in order. The solder tank 1, the heat conduction plate 2, the surface heater 3, and the heat insulating material have a four-layer structure.

面ヒーター３はその外面を断熱材のパネルで覆ったもので、一例としてはセラミックヒーターを用いる。セラミックヒーターは、図２に示すように発熱する抵抗体４をセラミックボード５内に埋没させ、図示しない断熱材のパネルでセラミックボードの外面を覆ったものである。従って、セラミックボード５の加熱面である内面は、抵抗体４の付近では高温となり、抵抗体４から離れると低温となり、温度バラツキが生ずる。また、熱伝導板２の材料としては、面ヒーター３の熱で溶けないもの、例えばステンレスを用いる。 The surface heater 3 has an outer surface covered with a panel of heat insulating material. As an example, a ceramic heater is used. As shown in FIG. 2, the ceramic heater has a resistor 4 that generates heat embedded in a ceramic board 5 and covers the outer surface of the ceramic board with a panel of heat insulating material (not shown). Therefore, the inner surface which is the heating surface of the ceramic board 5 becomes high temperature in the vicinity of the resistor 4, and becomes low temperature away from the resistor 4, resulting in temperature variation. Further, as the material of the heat conductive plate 2, a material that does not melt by the heat of the surface heater 3, for example, stainless steel is used.

はんだ槽１はその底面には、補強用のリブ６が間隔をあけて付いており、リブ６，６同士の間に熱伝導板２、面ヒーター３を順番に配置して底面全域を覆い、リブ６，６同士の間に複数本のロッド７を架設して面ヒーター３の下側を支えてある。また、はんだ槽１の外周面も同様に上下に延びるリブ８が付いていると共に、リブ８の上下に支持プレート９を突出しているので、リブ８の左右では上下の支持プレート９，９の間に熱伝導板２、面ヒーター３を順番に配置して外周面の液面レベルＬとほぼ同じ高さよりも下側全域を覆い、ロッド１０を上下の支持プレート９に固定して、面ヒーター３の外側を支えてある。 Reinforcing ribs 6 are attached to the bottom surface of the solder tank 1 with an interval, and the heat conduction plate 2 and the surface heater 3 are arranged in order between the ribs 6 and 6 to cover the entire bottom surface. A plurality of rods 7 are installed between the ribs 6 and 6 to support the lower side of the surface heater 3. Also, the outer peripheral surface of the solder tank 1 is similarly provided with ribs 8 extending vertically, and the support plates 9 protrude above and below the ribs 8. Therefore, between the upper and lower support plates 9, 9 on the left and right sides of the ribs 8. The heat conduction plate 2 and the surface heater 3 are arranged in order to cover the entire region below the same level as the liquid surface level L of the outer peripheral surface, and the rod 10 is fixed to the upper and lower support plates 9 to fix the surface heater 3. The outside is supported.

また、はんだ槽１は、内部にはんだ送り室１１を有する。はんだ送り室１１は、液面レベルＬよりも下側に入口１２を設けると共に、液面レベルＬよりも上側に出口１３を設け、入口付近のポンプ１４の駆動によって、入口１２から内部にはんだが送り込まれ、最終的に出口１３からはんだが流出する。はんだ送り室１１の具体的な構造は、液面レベルＬよりも下側ではんだ槽１内を仕切り１５で上下に区画し、仕切り１５に入口１２をあけると共に、出口１３に向かう抜穴１６を入口１２とは別の箇所にあけ、抜穴１６にダクト１７を固定し、ダクト１７の上端にはノズル１８を液面レベルＬよりも上側まで起立して取り付けてある。ノズル１８は上端が開口して出口１３となっており、溶融はんだを流出可能としてある。 The solder tank 1 has a solder feeding chamber 11 inside. The solder feed chamber 11 is provided with an inlet 12 below the liquid level L and an outlet 13 above the liquid level L. By driving a pump 14 near the inlet, solder is introduced from the inlet 12 to the inside. The solder is finally discharged from the outlet 13. The specific structure of the solder feed chamber 11 is as follows. The interior of the solder bath 1 is divided vertically by a partition 15 below the liquid level L, and an inlet 12 is opened in the partition 15 and a hole 16 directed toward the outlet 13 is formed. A duct 17 is fixed to the hole 16 at a location different from the inlet 12, and a nozzle 18 is attached to the upper end of the duct 17 so as to stand above the liquid level L. The upper end of the nozzle 18 is open and serves as an outlet 13 so that molten solder can flow out.

（イ）（ロ）本発明のはんだ槽を示す縦断面図、Ａ−Ａ線断面図である。(A) (b) It is the longitudinal cross-sectional view which shows the solder tank of this invention, and AA sectional view. 面ヒーターを示す正面図である。It is a front view which shows a surface heater.

Explanation of symbols

１はんだ槽
２熱伝導板
３面ヒーター 1 Solder bath 2 Heat conduction plate 3 Surface heater

Claims

An outer peripheral surface of a solder bath having a solder feed chamber in which an inlet is provided below the solder level and an outlet is provided above the level and a pump is provided in the vicinity of the inlet. Among them, at least the entire region below the liquid level and the entire bottom surface of the solder tank are directly covered in the order of a heat conductive plate made of stainless steel and a ceramic board in which a heat generating resistor is embedded, and the heat conductive plate A solder bath, wherein the ceramic board is separated from the solder bath, and heat of the resistor is uniformly transmitted to the solder bath through the heat conductive plate.

A support plate is provided on the outer peripheral surface of the solder tank with an interval in the vertical direction, and the heat conducting plate and the ceramic board are fixed in a state of being arranged between the support plates. The solder bath according to claim 1.

Using the solder bath according to claim 1 or 2,
At least the entire region below the liquid level and the entire bottom surface of the solder bath on the outer peripheral surface of the solder bath so that the heat generated from the resistor is transferred to the solder bath via the heat conducting plate. A method of heating the solder bath that heats uniformly.