JPS61116058A - Two-cycle internal-combustion engine - Google Patents

Two-cycle internal-combustion engine

Info

Publication number
JPS61116058A
JPS61116058A JP23543984A JP23543984A JPS61116058A JP S61116058 A JPS61116058 A JP S61116058A JP 23543984 A JP23543984 A JP 23543984A JP 23543984 A JP23543984 A JP 23543984A JP S61116058 A JPS61116058 A JP S61116058A
Authority
JP
Japan
Prior art keywords
crankcase
fan housing
single piece
lower half
cylinder
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
JP23543984A
Other languages
Japanese (ja)
Other versions
JPH0347424B2 (en
Inventor
Tetsuzo Fujikawa
藤川 哲三
Michichika Uda
宇田 亨爾
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Kawasaki Heavy Industries Ltd
Original Assignee
Kawasaki Heavy Industries Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Kawasaki Heavy Industries Ltd filed Critical Kawasaki Heavy Industries Ltd
Priority to JP23543984A priority Critical patent/JPS61116058A/en
Publication of JPS61116058A publication Critical patent/JPS61116058A/en
Publication of JPH0347424B2 publication Critical patent/JPH0347424B2/ja
Granted legal-status Critical Current

Links

Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02FCYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
    • F02F7/00Casings, e.g. crankcases or frames
    • F02F7/0043Arrangements of mechanical drive elements
    • F02F7/0046Shape of casings adapted to facilitate fitting or dismantling of engine parts
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02BINTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B75/00Other engines
    • F02B75/02Engines characterised by their cycles, e.g. six-stroke
    • F02B2075/022Engines characterised by their cycles, e.g. six-stroke having less than six strokes per cycle
    • F02B2075/025Engines characterised by their cycles, e.g. six-stroke having less than six strokes per cycle two

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Cylinder Crankcases Of Internal Combustion Engines (AREA)

Abstract

PURPOSE:To reduce the number of parts used and suppress the man-hours in assembly process by dividing a crank case construction into two, up and below, with the crank axis as the boundary of dividing, and by forming the upper half in the center of fan housing and cylinder and the lower half in the lower part of the fan housing solidly each as in a single piece. CONSTITUTION:A crank case 1 is divided into two up and below with the crank axis as the boundary of dividing. A fan housing 6 is divided into three; an upper part 7, a central part 8 and lower part 9 the latter two being formed as a box. The upper half 2 of the crank case 1 is made from aluminum by die-casting as in a single piece with the cylinder 5 and the said central part 8. The lower half 3 is made also as in a single piece with the said lower part 9. The upper part 7 is made from resin as in a single piece with the said lower part 9. The upper part 7 is made from resin as in a single piece with a cooling wind cover 10 and a muffler cover 11. Thereafter the upper half 2 and the central part 8 are coupled with the lower half 3 and the lower half 9 using bolts etc. This can well reduce the number of parts used as well as suppress the man-hours required in assembly process.

Description

【発明の詳細な説明】 (産業上の利用分野) 本発明は主として刈払機等に用いられる2サイクル内燃
機関に関する。
DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a two-stroke internal combustion engine mainly used in brush cutters and the like.

(従来技術及びその問題点) 従来の2サイクル内燃機関では、例えばクランクケース
は左右に2分割されており、またシリンダやファンハウ
ジング等もそれぞれクランクケースとは別体物とし構成
されている。そのために次のような不具合がある。
(Prior Art and its Problems) In a conventional two-stroke internal combustion engine, for example, the crankcase is divided into left and right halves, and the cylinder, fan housing, etc. are each constructed separately from the crankcase. This causes the following problems.

(1)シリンダ及びハウジング等の部品の数が多いため
に、各部品間の取付面の加工、締付レプねじ孔の加工及
び位置決めノックビン孔の加工等が必要になると八に、
多くのガスケット類、ねじ類及びノックビン類が必要に
なり、組立て工数がふえる。
(1) Due to the large number of parts such as cylinders and housings, it is necessary to process the mounting surfaces between each part, the tightening screw holes, and the positioning dowel holes.
Many gaskets, screws, and knock bottles are required, which increases the number of assembly steps.

(2)部品の組立て順序が制限される。例えばクランク
軸をクランクケースに装着した後でないとクランク軸に
フライホイルを装着できない。
(2) The assembly order of parts is restricted. For example, the flywheel cannot be attached to the crankshaft until after the crankshaft has been attached to the crankcase.

(3)上記(1)(2>により、コスト高、重量増及び
大型化を避けることが内列である。
(3) According to (1) and (2) above, it is essential to avoid high costs, increased weight, and increased size.

(問題を解決するための手段) 上記問題を解決するために本発明は、クランクケースを
クランク軸中心を境として上下に2分割し、クランクケ
ース上半部をシリンダ及びファンハウジングの箱状中央
部と一体に形成し、クランクケース下半部をファンハウ
ジングの箱状下部と一体に形成している。
(Means for Solving the Problems) In order to solve the above problems, the present invention divides the crankcase into upper and lower halves with the center of the crankshaft as the border, and divides the upper half of the crankcase into the box-shaped center of the cylinder and fan housing. The lower half of the crankcase is integrally formed with the box-shaped lower part of the fan housing.

(実施例) 第1図において、クランクケース1はクランク軸中心O
を境として上半部2と下半部3とに上下に2分割されて
いる。ファンハウジング6は上部7と箱状の中央部8と
箱状の下部9とに3分割されている。クランクケース上
半部2はアルミダイカスト成型によりシリンダ5及びフ
ァンハウジング6の箱状中央部8と一体に形成されてい
る。クランクケース上半部3はアルミダイカスト成型に
よりファンハウジング6の下部9と一体に形成されてい
る。ファンハウジング6の上部7は樹脂により冷l!I
J!Iカバー10及びマフラカバー11と一体に形成さ
れている。
(Example) In Fig. 1, the crankcase 1 is located at the crankshaft center O.
It is vertically divided into an upper half part 2 and a lower half part 3 with the border as the border. The fan housing 6 is divided into three parts: an upper part 7, a box-shaped central part 8, and a box-shaped lower part 9. The crankcase upper half 2 is integrally formed with the cylinder 5 and the box-shaped central portion 8 of the fan housing 6 by aluminum die-casting. The crankcase upper half 3 is integrally formed with the lower part 9 of the fan housing 6 by aluminum die casting. The upper part 7 of the fan housing 6 is cooled by resin! I
J! It is formed integrally with the I cover 10 and the muffler cover 11.

縦断面図を示す第2図において、クランクケース1の上
半部2及びハウシング6の中央部8は複数本のボルト等
によりクランクケース1の下半部3及ハウジング6の下
半部9に締結されている。
In FIG. 2, which shows a longitudinal cross-sectional view, the upper half 2 of the crankcase 1 and the central portion 8 of the housing 6 are fastened to the lower half 3 of the crankcase 1 and the lower half 9 of the housing 6 using a plurality of bolts or the like. has been done.

クランクケース1の上半部2とF半部3の間には左右1
対の軸受12.12のアウターレース及び左右1対のシ
ール13.13が一定の圧力で保持されており、軸受1
2のインブーレースにクランク軸15が圧入されている
。クランク@15の右端部はリコイルスタータケース1
6内に延び、その先端部にはりコイルスタータ用プーリ
17が固着されている。18はりコイルスタータ用の取
手である。
Between the upper half 2 and the F half 3 of the crankcase 1, there is a
The outer races of the pair of bearings 12.12 and the pair of left and right seals 13.13 are held at a constant pressure, and the bearing 1
A crankshaft 15 is press-fitted into the inlet race of No. 2. The right end of crank @15 is recoil starter case 1
6, and a coil starter pulley 17 is fixed to its tip. This is a handle for an 18-beam coil starter.

クランク軸15の左端部はファンハウジング6内へと延
び、その先端部にはナツト19等によりフライホイル2
0が固着されている。フライホイル20の右面には複数
枚のファン21が放射状に設けられ、フライホイル20
の左面にはクラッチシュー取付部22が形成されており
、取付部22には支軸23を介してクラッチシュー24
が回動自在に支持されている。ハウジング6の左面には
例えば刈払機のクラッチハウジングが固着される。
The left end of the crankshaft 15 extends into the fan housing 6, and the flywheel 2 is attached to the tip by a nut 19 or the like.
0 is fixed. A plurality of fans 21 are provided radially on the right side of the flywheel 20, and the flywheel 20
A clutch shoe attachment part 22 is formed on the left side of the clutch shoe 24 , and a clutch shoe 24 is attached to the attachment part 22 via a support shaft 23 .
is rotatably supported. For example, a clutch housing for a brush cutter is fixed to the left side of the housing 6.

フ7ンハウジングング上部7はボルト27によりハウジ
ング中央部8の上面に固着されており、上部7と一体の
冷却風カバー10はシリンダ5を覆っている。30はピ
ストンであって、ピストンピン32、コネクティングロ
ッド33、クランクビン34及びクランクアーム35を
介してクランク軸15に連結している。またピストンに
はピストンリング(図示せず)を嵌装している。36は
燃料タンクであって、バンド37によりクランクケース
1の下側に固定されている。
A fan housing upper part 7 is fixed to the upper surface of the housing center part 8 by bolts 27, and a cooling air cover 10 integrated with the upper part 7 covers the cylinder 5. A piston 30 is connected to the crankshaft 15 via a piston pin 32, a connecting rod 33, a crank pin 34, and a crank arm 35. Further, a piston ring (not shown) is fitted to the piston. 36 is a fuel tank, which is fixed to the lower side of the crankcase 1 by a band 37.

第2図の1−■断面を示す第3図において、マフラカバ
ー11はマフラ38を覆っている。3つは気化器である
In FIG. 3, which shows the cross section 1--■ in FIG. 2, the muffler cover 11 covers the muffler 38. Three are vaporizers.

第4図は第2図のIV−rV断面図であり、クランクケ
ース1の上半部3の取付面の形状を示している。40は
軸受取付面である。40−はクランクケース1の上半部
2と下半部3の位置決め用ノックピンであり、1対は取
付面に対し凸、他の1対は取付面に対し凹となっている
FIG. 4 is a sectional view taken along the line IV-rV in FIG. 2, and shows the shape of the mounting surface of the upper half 3 of the crankcase 1. 40 is a bearing mounting surface. Reference numeral 40- designates knock pins for positioning the upper half 2 and lower half 3 of the crankcase 1, one pair being convex with respect to the mounting surface and the other pair being concave with respect to the mounting surface.

(作用) 内燃は関を組立てる場合には、クランク軸15に左右の
軸受12.12、シール13.13、フライホイル20
及びリコイルスタータのプーリ17を予め装着しておく
と共に、クランクビン34、コネクティングロッド33
及びピストンピン32を介してピストン30を連結して
おく。
(Function) When assembling the internal combustion engine, the left and right bearings 12, 12, seals 13, 13, and flywheel 20 are attached to the crankshaft 15.
In addition to installing the pulley 17 of the recoil starter in advance, the crank bin 34 and the connecting rod 33 are installed in advance.
A piston 30 is connected via a piston pin 32.

そして上記のクランク軸15のユニットをクランクケー
ス1の下半部3に嵌込む。即ちピストン30をシリンダ
5の内径(内周部)に挿入しつつ、軸受12.12をク
ランクケース下半部3の軸受取付面40に嵌める。つぎ
に上方からクランクケース1の上半部2とファンハウジ
ング6の中央部8のユニットを締着する。またハウジン
グ中央部8の上端にハウジングの上部9を固着する。
Then, the above crankshaft 15 unit is fitted into the lower half 3 of the crankcase 1. That is, while inserting the piston 30 into the inner diameter (inner circumference) of the cylinder 5, the bearings 12, 12 are fitted into the bearing mounting surface 40 of the lower half 3 of the crankcase. Next, the upper half 2 of the crankcase 1 and the central part 8 of the fan housing 6 are fastened together from above. Further, the upper part 9 of the housing is fixed to the upper end of the central part 8 of the housing.

(別の実施例) 第5〜第8図に示す実施例は、刈払機の取付部、即ちク
ラッチハウジング41を上側部41aと下側部41bに
2分割し、上側部41aをファンハウジング6の中央部
8及びクランクケース1の上半部2と一体に形成し、下
側部41bをファンハウジング6の下部9及びクランク
ケース1の下半部3と一体に形成している。
(Another embodiment) In the embodiment shown in FIGS. 5 to 8, the attachment part of the brush cutter, that is, the clutch housing 41 is divided into two parts, an upper part 41a and a lower part 41b, and the upper part 41a is attached to the fan housing 6. It is formed integrally with the central part 8 and the upper half part 2 of the crankcase 1, and the lower part 41b is integrally formed with the lower part 9 of the fan housing 6 and the lower half part 3 of the crankcase 1.

クラッチハウジング41内には第6図に示すように軸受
43を介してクラッチドラム44が回転自在に支持され
ており、ドラム44の内周面はクラッチシュー24に対
向している。
As shown in FIG. 6, a clutch drum 44 is rotatably supported within the clutch housing 41 via a bearing 43, and the inner peripheral surface of the drum 44 faces the clutch shoe 24.

なお第5〜第8図に丞づ゛実施例において、上記クラッ
チハウジング41以外の構造は第1〜第4図のものと同
様であり、従って第1〜第4図に対応する部品には第1
〜第4図のものと同じ番号を付しである。
In the embodiment shown in Figs. 5 to 8, the structure other than the clutch housing 41 is the same as that in Figs. 1 to 4, so the parts corresponding to Figs. 1
- The same numbers as those in FIG. 4 are given.

〈作用) 組立ての要領は前記第1〜第4図のものと略同様である
(Function) The assembly procedure is substantially the same as that shown in FIGS. 1 to 4 above.

ただし第5〜第8図のものでは、刈払機のクラッチハウ
ジング41もクランクケース1と一体に形成されている
ので、クランク軸芯0と刈払機側の回転軸心〇−との1
mの芯ずれをなくすことができる。それにより刈払機の
撮動を減少させることができる。
However, in the models shown in FIGS. 5 to 8, the clutch housing 41 of the brush cutter is also formed integrally with the crankcase 1, so that the crank shaft center 0 and the rotation shaft center 0- of the brush cutter are 1
It is possible to eliminate misalignment of m. Thereby, it is possible to reduce the number of shots taken by the brush cutter.

(発明の効果) (1)クランクケース上半部、ファンハウジング中央部
およびシリンダを一体物として形成し、クランクケース
下半部及びファンハウジング下部を一体物として形成し
ており、また当機関を搭載する作業償の部品の一部(例
えば刈払機のクラッチハウジング等)をも一体物として
形成できるので、ガスケット類、ねじ類及び位置決め用
ノックビン類の数を減らすことができると共に、取付面
の加工、締付けねじ孔の加工及び位置決めノックビン孔
の加工を大幅に減少させることができる。
(Effects of the invention) (1) The upper half of the crankcase, the center of the fan housing, and the cylinder are formed as one body, and the lower half of the crankcase and the lower part of the fan housing are formed as one body, and this engine is installed. Some of the parts that require additional work (for example, the clutch housing of a brush cutter, etc.) can be formed as a single piece, so the number of gaskets, screws, and positioning knock pins can be reduced, and the mounting surface can be processed easily. The machining of tightening screw holes and the machining of positioning dowel holes can be significantly reduced.

それにより部品点数の削減と加工時間及び組立時間の短
縮を達成することができ、製造コストが安くなる。また
内燃機関の重量の軽減も達成できる。
This makes it possible to reduce the number of parts, reduce processing time and assembly time, and lower manufacturing costs. It is also possible to reduce the weight of the internal combustion engine.

(2)クランクケースを上下に2分割し、しかも上半部
にはシリンダ及びファンハウジングの中央部を一体に形
成し、下半部にはファンハウジングの下部を一体に形成
しているので、機関組立て時にはクランク軸に予め軸受
、オイルシール、フライホイル及びリコイルスタータの
プーリ、さらにはピストン等を組付けておくことができ
、そのようなりランク軸の1ニツトとしてクランクケー
スに装着することができる。
(2) The crankcase is divided into upper and lower halves, with the cylinder and fan housing centrally formed integrally in the upper half, and the lower part of the fan housing integrally formed in the lower half. At the time of assembly, bearings, oil seals, flywheels, recoil starter pulleys, pistons, etc. can be pre-assembled to the crankshaft, and in this way it can be installed in the crankcase as one part of the crankshaft.

即ち組立て工程上の順序の制限が大幅に減ることにより
、幾つかの組立て行程を1つにまとめることができ、組
立ての自動化と組立工数の削減を達成することができる
。従ってより一層の製造コストの低減を達成することが
できる。
That is, by significantly reducing restrictions on the order of assembly processes, it is possible to combine several assembly processes into one, thereby achieving automation of assembly and reduction of assembly man-hours. Therefore, further reduction in manufacturing costs can be achieved.

(3)機関を搭載する作業機の軸受部(例えば刈払機の
クラッチドラム軸受等)を一体形成することにより、ク
ランク軸軸心と作業別軸軸心の心図れが少なくなり、撮
動が減少する。また作業機軸受にかかる負荷も減少する
ため、軸受が小型化できるので軽量化が可能となり、刈
払機等の携帯する作業機においては作業機の疲労が大幅
に減少する。
(3) By integrally forming the bearing part of the working machine equipped with the engine (for example, the clutch drum bearing of a brush cutter, etc.), there is less misalignment between the crankshaft center and the work-specific shaft center, which reduces the need for photographing. do. Furthermore, since the load on the working machine bearing is reduced, the bearing can be made smaller and lighter, and in portable working machines such as brush cutters, fatigue of the working machine is significantly reduced.

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

第1図は本発明の第1実施例の分解斜視図、第2図は第
1実施例の縦断面図、第3、第4図はそれぞれ第2図の
■−■、TV−IV断面図、第5図は第2実施例の分解
斜視図、第6図は第2実施例の縦断面図、第7、第8図
はそれぞれ第6図のVI −■、■−■断面図である。 1・・・クランクケース、2.3・・・上半部、下半部
、5・・・シリンダ、6・・・ファンハウジング、7.
8.9、・・・上部、中央部、下部、10・・・冷却風
カバー、11・・・マフラカバー第2図 ML 第6図 第γ図
Fig. 1 is an exploded perspective view of the first embodiment of the present invention, Fig. 2 is a vertical sectional view of the first embodiment, and Figs. 3 and 4 are sectional views taken along ■-■ and TV-IV in Fig. 2, respectively. , FIG. 5 is an exploded perspective view of the second embodiment, FIG. 6 is a longitudinal cross-sectional view of the second embodiment, and FIGS. 7 and 8 are VI-■ and ■-■ cross-sectional views of FIG. 6, respectively. . 1... Crank case, 2. 3... Upper half, lower half, 5... Cylinder, 6... Fan housing, 7.
8.9, ... upper part, center part, lower part, 10 ... cooling air cover, 11 ... muffler cover Fig. 2 ML Fig. 6 Fig. γ

Claims (1)

【特許請求の範囲】[Claims] クランクケースをクランク軸中心を境として上下に2分
割し、クランクケース上半部をシリンダ及びファンハウ
ジングの箱状中央部と一体に形成し、クランクケース下
半部をファンハウジングの箱状下部と一体に形成したこ
とを特徴とする2サイクル内燃機関。
The crankcase is divided into two parts, upper and lower, with the center of the crankshaft as the boundary, the upper half of the crankcase is formed integrally with the box-shaped center part of the cylinder and fan housing, and the lower half of the crankcase is integrated with the box-shaped lower part of the fan housing. A two-stroke internal combustion engine characterized by having the following features:
JP23543984A 1984-11-08 1984-11-08 Two-cycle internal-combustion engine Granted JPS61116058A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP23543984A JPS61116058A (en) 1984-11-08 1984-11-08 Two-cycle internal-combustion engine

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP23543984A JPS61116058A (en) 1984-11-08 1984-11-08 Two-cycle internal-combustion engine

Publications (2)

Publication Number Publication Date
JPS61116058A true JPS61116058A (en) 1986-06-03
JPH0347424B2 JPH0347424B2 (en) 1991-07-19

Family

ID=16986125

Family Applications (1)

Application Number Title Priority Date Filing Date
JP23543984A Granted JPS61116058A (en) 1984-11-08 1984-11-08 Two-cycle internal-combustion engine

Country Status (1)

Country Link
JP (1) JPS61116058A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103644021A (en) * 2013-12-08 2014-03-19 许岩 Dedicated cylinder head silencer cover protection assembling unit for ground auger engine cylinder head silencer
JP2014062473A (en) * 2012-09-20 2014-04-10 Fuji Heavy Ind Ltd Engine

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5476403U (en) * 1977-04-30 1979-05-31
JPS5922256U (en) * 1982-08-03 1984-02-10 埴岡 盛作 ×× Cutting part structure of tape cutter

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5476403U (en) * 1977-04-30 1979-05-31
JPS5922256U (en) * 1982-08-03 1984-02-10 埴岡 盛作 ×× Cutting part structure of tape cutter

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2014062473A (en) * 2012-09-20 2014-04-10 Fuji Heavy Ind Ltd Engine
CN103644021A (en) * 2013-12-08 2014-03-19 许岩 Dedicated cylinder head silencer cover protection assembling unit for ground auger engine cylinder head silencer

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