JPH0346727A - Electromagnetic switch - Google Patents

Abstract

PURPOSE:To realize low cost and miniaturization and improve reliability of a switch by providing a protruding portion on the abutting surface of a packing so as to surround a contact chamber. CONSTITUTION:The formation surface of a protruding portion 14c is interposedly provided in a cap 6 side between a fixed iron core 3 and the cap 6 in a packing 14. The packing 14 is made line abutting since it abuts the cap 6 and the protruding portion 14c and even some dispersion exists in dimensional accuracy in the iron core 3 and the cap 6, the sealing of an abutted surface is sufficiently ensured with the protruding part 14c to realize low cost. Moreover since pressing force to the packing 14 is small, the possibility of the bulge of the center part is eliminated. Consequently even the diameter of a hole 14b' is made small so that the center part of a packing 7 is positioned between a movable contact 11 and the iron core 3, the contact of the packing 14 to the contact 11 is eliminated and a sufficient creeping distance is obtained, and since the space between a fixed contact 12 and the iron core 3 can be minimized, miniaturization can be realized and high reliability can be obtained.

Description

【発明の詳細な説明】 〔産業上の利用分野〕 この発明は主として機関を始動させる始動電動機に用い
られる電磁スイッチに関するものである。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electromagnetic switch mainly used in a starter motor for starting an engine.

〔従来の技術〕[Conventional technology]

第２図は始動電動機に用いられる従来の電磁スイツチの
断面図である０図中、１は円筒状の継鉄で、その内周側
には励磁コイル２が設けられている。継鉄１の後端部（
図面左方向）には固定側磁極を構成する固定鉄心３が固
定され、また固定鉄心３の中央部は励磁コイル２内周の
内部通路４内に所定長突出している。内部通路４には固
定鉄心３に対向して可動側磁極を構成する可動鉄心５が
軸方向移動可能に配設されている。FIG. 2 is a sectional view of a conventional electromagnetic switch used in a starting motor. In FIG. 2, numeral 1 is a cylindrical yoke, and an excitation coil 2 is provided on the inner circumferential side of the yoke. Rear end of yoke 1 (
A fixed iron core 3 constituting a fixed side magnetic pole is fixed to the left side of the drawing, and a central portion of the fixed iron core 3 protrudes a predetermined length into an internal passage 4 on the inner periphery of the exciting coil 2. A movable core 5, which constitutes a movable magnetic pole, is disposed in the internal passage 4 so as to be movable in the axial direction, facing the fixed core 3.

固定鉄心３の後側には樹脂からなるキャップ６が設けら
れ、継鉄１後端のインロ一部１ａに固定鉄心３と共にか
しめ固着されており、また固定鉄心３とキャップ６との
間にはゴムからなるパツキン７が介在設置されている。A cap 6 made of resin is provided on the rear side of the fixed iron core 3, and is caulked and fixed together with the fixed iron core 3 to the spigot part 1a at the rear end of the yoke 1. Also, between the fixed iron core 3 and the cap 6, A gasket 7 made of rubber is interposed therebetween.

このパツキン７は第３ｒｐＪに示すように中心部に後述
するロンドを挿通させるための孔７ａを有したいわゆる
ドーナツ状に形成され、また励磁コイル２の口出線挿通
用の日出孔７ａが形成されている。９は固定鉄心３の中
心部に軸方向移動可能に配設されたロンドで、接点室８
に位置する後端部には絶縁体１０を介して可動接点１１
が設けられており、この可動接点１１がキャップ６に固
定された固定接点１２に当接するよう構成されている。As shown in 3rd rpJ, this gasket 7 is formed in a so-called donut shape with a hole 7a in the center for inserting a rond, which will be described later, and a sun hole 7a for inserting the output wire of the excitation coil 2. has been done. Reference numeral 9 denotes a rond disposed in the center of the fixed iron core 3 so as to be movable in the axial direction, and a contact chamber 8.
A movable contact 11 is connected to the rear end located at the insulator 10.
is provided, and the movable contact 11 is configured to come into contact with a fixed contact 12 fixed to the cap 6.

また、１３は励磁コイル２の口出線を導出する日出部で
ある。Further, 13 is a sunrise part from which a lead wire of the excitation coil 2 is derived.

〔発明が解決しようとする課題〕[Problem to be solved by the invention]

従来の電磁スイッチは上記のように構成されており、接
点室８を密閉状態とし、キャップ６と固定鉄心３との接
合面からの浸水を防止するためにパツキン７が設けられ
ている。また、上記電磁スイッチはその固定接点１２が
バッテリに接続されて常時正電位であり、また継鉄１お
よび固定鉄心３はアースされて常時負電位となっており
、しかも固定接点１２前端面と固定鉄心３後端面との間
隔も小さいため、パツキン７によって固定接点１２と固
定鉄心３間の沿面距離を大きくする必要がある。このた
めパツキン７の孔７ａ径も可能な限り小さくなるよう構
成されている。The conventional electromagnetic switch is constructed as described above, and a packing 7 is provided to seal the contact chamber 8 and prevent water from entering through the joint surface between the cap 6 and the fixed core 3. In addition, the fixed contact 12 of the electromagnetic switch is connected to the battery and is always at a positive potential, and the yoke 1 and the fixed iron core 3 are grounded and always have a negative potential. Since the distance from the rear end surface of the iron core 3 is also small, it is necessary to increase the creepage distance between the fixed contact 12 and the fixed iron core 3 using the packing 7. For this reason, the diameter of the hole 7a of the packing 7 is also configured to be as small as possible.

しかしながら上記従来の電磁スイッチは、パツキン７の
締代となっている部分、すなわちキャップ６の当接部分
（第４図斜線部Ｂで示す）の面積が大きいため、確実な
シール効果を得るのに適正な締代の制限があり、従って
高い部品精度が要求されることからコスト高となってい
た。However, in the above-mentioned conventional electromagnetic switch, the area of the tightening portion of the packing 7, that is, the abutting portion of the cap 6 (shown by the shaded area B in FIG. 4) is large, so it is difficult to obtain a reliable sealing effect. There is a limit to the appropriate tightening margin, and therefore high component precision is required, resulting in high costs.

また、パツキン７は、上述したように当接面積が大きく
、かつ比較的大きな圧力で押圧されるため、押圧されて
いない中心部がふくらみ、第５図に示すようにパツキン
６が可動接点１１に接触してしまう状態が発生し、この
ような状態に至ると、可動接点１１の繰り返し接触によ
るパツキン７の摩耗粉の発生で可動接点１１と固定接点
１２との導通不良が発生する問題や、高温環境下放置に
よってパツキン７と可動接点１１とが固着し、可動接点
１１の動作不良が発生する問題等があった。Furthermore, as described above, the seal 7 has a large contact area and is pressed with a relatively large pressure, so the center part that is not pressed swells, and the seal 6 is attached to the movable contact 11 as shown in FIG. If a situation occurs in which contact occurs, there may be problems such as poor conduction between the movable contact 11 and the fixed contact 12 due to the generation of abrasion powder on the packing 7 due to repeated contact of the movable contact 11, or high temperature When left in the environment, the gasket 7 and the movable contact 11 become stuck together, causing problems such as malfunction of the movable contact 11.

特にこのような問題は、固定接点１２と固定鉄心３との
間隔が接近しているほど沿面距離を大きくするためにパ
ツキン７を内周側まで延ばさなければならない点と、パ
ツキン７と可動接点１１との間隔を大きくできない点で
顕著となり、従ってこのような問題の発生を防止するた
めには固定接点１２と固定鉄心３との間隔を大きくしな
ければならないが、このような構造をとると装置が大き
くなってしまうという別の問題を発生させていた。In particular, such a problem is that the closer the distance between the fixed contact 12 and the fixed iron core 3 is, the more the seal 7 must be extended to the inner circumference in order to increase the creepage distance, and Therefore, in order to prevent such a problem from occurring, it is necessary to increase the distance between the fixed contact 12 and the fixed iron core 3, but if such a structure is adopted, the equipment This caused another problem in that the size of the image became large.

この発明は上記従来の問題点を解決するためになされた
もので、低コスト化が図れ、かつ信頼性の向上した電磁
スイッチを得ることを目的とする。This invention was made to solve the above-mentioned conventional problems, and aims to provide an electromagnetic switch that can be manufactured at low cost and has improved reliability.

〔課題を解決するための手段〕[Means to solve the problem]

この発明に係る電磁スイッチは、キャップと固定鉄心と
の間に介在設置されるパツキンの少なくともキャップと
固定鉄心とのいずれか一方の当接面に、該当接面上で接
点室を包囲する凸部を形成したものである。In the electromagnetic switch according to the present invention, a convex portion surrounding a contact chamber on the contact surface of at least one of the cap and the fixed core of the packing interposed between the cap and the fixed core is provided. was formed.

〔作　用］ この発明においては、パツキンの締代部分が面当接から
線当接となるため当接部に高い寸法精度が要求されず、
また当接部以外のパツキンのふくれが発生しない。[Function] In this invention, since the tightening portion of the packing changes from surface contact to line contact, high dimensional accuracy is not required for the contact portion.
Also, the seals do not bulge in areas other than the contact areas.

〔実施例〕〔Example〕

第１図（ａ）（ハ）はこの発明の一実施例による電磁ス
イッチのパツキン１４を示す平面図およびＣ−Ｃ線断面
図である。このパツキン１４はその一表面側の外周と口
出７Ｊ、１４ｂ内周側を包囲するよう連続した線状の凸
部１４ｃが形成されている。また、１４ａは従来のパツ
キン７の孔７ａと同様の孔である。FIGS. 1(a) and 1(c) are a plan view and a sectional view taken along the line C--C, showing a packing 14 of an electromagnetic switch according to an embodiment of the present invention. This packing 14 is formed with a continuous linear convex portion 14c so as to surround the outer periphery on one surface side and the inner periphery side of the openings 7J and 14b. Further, 14a is a hole similar to the hole 7a of the conventional gasket 7.

このように形成されたパツキン１４は従来と同様に固定
鉄心３とキャップ６との間に凸部１４ｃ形成面をキャッ
プ６側にして介在設置される。この場合、パツキン１４
はキャップ６と凸部１４ｃで当接するため、締代部分は
従来の面当接から線当接となる。従って固定鉄心３とキ
ャップ６との寸法精度に多少のばらつきがあっても、こ
れら固定鉄心３とキャップ６との当接面のシールは凸部
１４ｃによって十分に確保される。また、パツキン１４
への押圧力も小さいため、中心部がふくれる恐れもなく
、従ってパッキン７中心部が可動接点１１と固定鉄心３
との間に位置するよう孔１４ａ径を小さ（してもパツキ
ン１４が可動接点１１に接触することがなく、十分な沿
面距離が得られ、固定接点１交と固定鉄心３との間隔を
小さくすることができるため電磁スイッチの小型化を図
ることができる。The packing 14 formed in this manner is interposed between the fixed iron core 3 and the cap 6 with the surface on which the convex portion 14c is formed facing the cap 6 as in the conventional case. In this case, Patsukin 14
Since the cap 6 contacts the convex portion 14c, the interference portion changes from the conventional surface contact to a line contact. Therefore, even if there is some variation in the dimensional accuracy between the fixed core 3 and the cap 6, the convex portion 14c ensures a sufficient seal on the abutting surfaces between the fixed core 3 and the cap 6. Also, Patsukin 14
Since the pressing force on the packing 7 is small, there is no fear that the center part will swell.
The diameter of the hole 14a is made small so that the hole 14a is located between the Therefore, the size of the electromagnetic switch can be reduced.

なお、上記実施例ではパツキン１４の外周と口出部１４
ｂ内周側に凸部１４ｃを形成したが、この形成位置に限
定されるものではなく、少なくとも当接面上で接点室８
を包囲する位置であれば上記実施例と同様の効果を奏す
る。In addition, in the above embodiment, the outer periphery of the packing 14 and the opening part 14
b Although the convex portion 14c is formed on the inner peripheral side, the formation position is not limited to this, and the contact chamber 8 is formed at least on the contact surface.
The same effect as in the above embodiment can be obtained if the position surrounds the .

また、パツキン１４の凸部１４ｃ形成面もキャップ６側
としたが、固定鉄心３側でも良く、更にパツキン１４の
両面に形成しても良い。Furthermore, although the convex portion 14c of the packing 14 is formed on the cap 6 side, it may also be formed on the fixed core 3 side, or may be formed on both sides of the packing 14.

〔発明の効果〕〔Effect of the invention〕

以上のようにこの発明の電磁スイッチによれば、パツキ
ンの当接面上に接点室を包囲するよう凸部を設けたので
、パツキンの当接部が線当接となるため、パツキン当接
部の部品精度に高い精度が要求されず、十分な防水効果
が得られ、従って低コスト化を図ることができる。しか
もパツキン当接部の押圧力も小さくて済むためパツキン
のふくれ発生がなく、従って接点の導通不良発生もなく
、小型で信頼性の高い電磁スイッチが得られる効果があ
る。As described above, according to the electromagnetic switch of the present invention, since the convex portion is provided on the contact surface of the packing so as to surround the contact chamber, the contact portion of the packing comes into line contact. High accuracy is not required for the precision of the parts, a sufficient waterproofing effect can be obtained, and therefore costs can be reduced. Moreover, since only a small pressing force is required on the seal abutting portion, the seal does not bulge, and therefore there is no conduction failure at the contacts, resulting in a compact and highly reliable electromagnetic switch.

【図面の簡単な説明】[Brief explanation of drawings]

第１図（ａ）はこの発明の一実施例による電磁スイッチ
のパツキンの正面図、第１図〜）は第１図（ａ）のＣ−
Ｃ線断面図、第２図は従来の電磁スイッチの断面図、第
３図（ａ）は同電磁スイッチのパツキンの正面図、第３
図ら）は第３図（ａ）のＡ−ＡｖＡ断面図、第４図は同
パツキンの当接状態を示す正面図、第５図は従来のｉｔ
Ｍ１スイッチのパツキンと可動接点との固着状態を示す
断面図である。 ３・・・固定鉄心、６・・・キャップ、８・・・接点室
、１１・・・可動接点、１２・・・固定接点、１４・・
・パツキン、１４ｃ・・・凸部。 なお、図中、同一符号は同一または相当部分を示す。FIG. 1(a) is a front view of a packing of an electromagnetic switch according to an embodiment of the present invention, and FIGS.
2 is a sectional view of a conventional electromagnetic switch, 3(a) is a front view of the gasket of the same electromagnetic switch, 3.
Fig. 4) is a sectional view taken along line A-AvA in Fig. 3(a), Fig. 4 is a front view showing the contact state of the packing, and Fig. 5 is a conventional IT
FIG. 3 is a cross-sectional view showing a state in which the packing of the M1 switch and the movable contact are fixed. 3... Fixed iron core, 6... Cap, 8... Contact chamber, 11... Movable contact, 12... Fixed contact, 14...
・Patsukin, 14c...Protrusion. In addition, in the figures, the same reference numerals indicate the same or corresponding parts.

Claims (1)

【特許請求の範囲】[Claims] 固定鉄心と、この固定鉄心の端面に当接し、該固定鉄心
端面との間に可動接点と固定接点とが位置する接点室を
形成するキャップと、これらキャップと固定鉄心との当
接面に配設され、前記接点室を密閉状態に保持する弾性
体からなるパッキンとを備えた電磁スイッチにおいて、
前記パッキンの少なくとも前記キャップと固定鉄心との
いずれか一方の当接面に、該当接面上で前記接点室を包
囲する凸部を形成したことを特徴とする電磁スイッチ。A fixed core, a cap that abuts the end face of the fixed core and forms a contact chamber in which a movable contact and a fixed contact are located between the fixed core end face, and a cap disposed on the contact face between these caps and the fixed core. and a packing made of an elastic body that maintains the contact chamber in a sealed state,
An electromagnetic switch characterized in that a convex portion surrounding the contact chamber is formed on the contact surface of at least one of the cap and the fixed core of the packing.