JPS6045761A - Carbureter - Google Patents

Abstract

PURPOSE:To vary the preset rpm.s used for warming-up of an engine when it is under the static and running states by disposing an engaging piece which comes out of engagement at the operating time of a throttle valve, between it and a choke valve. CONSTITUTION:Since a wax expanding rod 19 stays in the retracted position when an engine is at a low temperature, a cam 7 is pushed counterclockwise by the force of a spring 11 to be restricted at the preset position so that the opening of a throttle valve 2 is determined according to the position of a pin 5 which makes contact with a cam face. Once the temperature of the engine rises from such condition, the rod 19 is urged forth to turn the cam 7 further in the counterclockwise direction, however, a pin 5 comes into engagement with the end part of the second cam 8 pulled back by a spring 14 and therefore inhibits the closing motion of the throttle valve 2. Consequently, the warming up is promoted. When the throttle valve 2 is opened during driving of a car, the engagement between the second cam 8 and the pin 5 is released. If the throttle valve 2 is thereafter closed, the opening thereof is less than the preceding opening so that the shock at the driving time of a vehicle may be reduced.

Description

【発明の詳細な説明】 〔発明の利用分野〕 本発明は気化器に係シ、特に定置暖機特性および走行中
の暖機特性を改善するのに好適な内燃機関用オートチョ
ーク式気化器に関するものである。[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a carburetor, and more particularly to an auto-choke carburetor for an internal combustion engine suitable for improving stationary warm-up characteristics and warm-up characteristics during running. It is something.

〔発明の背景〕[Background of the invention]

一般にオートチョーク式気化器においては、内燃機関の
暖気中の機関回転数制御の手段として、感温部材で駆動
されるカム機構を利用し、カムとの連動機構によシ絞弁
開度を制御する方法を採用している。そして以前は、カ
ムの回動に対して絞弁開度が段階的に変化するようにす
る方式が一般的であシ、その変化手段は人為操作として
いた。Generally, auto-choke type carburetors use a cam mechanism driven by a temperature-sensitive member as a means of controlling the engine speed while the internal combustion engine is warming up, and the throttle valve opening is controlled by a mechanism that works in conjunction with the cam. The method is adopted. In the past, it was common to have the throttle valve opening change stepwise in response to the rotation of the cam, and the changing means was manually operated.

しかし、この方式では、人為操作を加えない場合は絞弁
開度が常に一定で、かつ、大きく設定され、暖気が進む
につれて機関回転数が高くなシ過ぎるという欠点を生ず
る。そのため、この欠点を補う方式として、近年、特公
昭５７−６７５６号公報に見られるようにカムの回動に
対して絞弁開度が連続的に円滑に変化するようにした機
構が採用されるようになった。この機構を採用したもの
は、カムの回動を感温部材によシ自動的に行うようにし
てあシ、絞弁開度を変えるのに人為操作が不要になると
いう利点がある。しかし、この方式には、絞弁開度が感
温部材の特性によシー義的に決定されるため、内燃機関
のどのような運転状態においても常に最適な運転が行わ
れるという保証がない。However, this system has the disadvantage that the throttle valve opening is always constant and set to a large value unless manual operation is applied, and as the engine warms up, the engine speed becomes too high. Therefore, as a method to compensate for this drawback, in recent years, a mechanism has been adopted in which the throttle valve opening degree changes continuously and smoothly in response to the rotation of the cam, as seen in Japanese Patent Publication No. 57-6756. It became so. The device employing this mechanism has the advantage that the rotation of the cam is automatically performed by the temperature-sensitive member, so that no manual operation is required to change the opening of the throttle valve. However, in this method, since the opening degree of the throttle valve is logically determined by the characteristics of the temperature-sensitive member, there is no guarantee that the internal combustion engine will always operate optimally in any operating state.

具体的には、低温時に車両を停止した状態で内燃機関を
暖機する場合、機関回転数が比較的扁い方が望ましく、
これが低く設定されると、暖機の促進が充分行われず、
したがって、チョーク弁の開きも遅くなシ、暖機時間が
長くなると同時に燃料経済性が著しく悪化し、かつ、車
室内の暖房が充分行われず、車室内の快適性が損なわれ
るという弊害が生ずる。一方、車輛の走行中においては
、機関回転数が低い方が望しく、これが高く設定される
と、走行中や減速時において車速かしばらく低下しない
という現象が起きたシ、あるいは、自動変速機付車輛の
場合　ａｔ　Ｄ　７ルンジで停止時に、回転数が高いた
め停止不可能となシ、突然発進するなどの危険を生ずる
可能性がある。Specifically, when warming up an internal combustion engine with the vehicle stopped at low temperatures, it is desirable for the engine speed to be relatively low;
If this is set low, warm-up will not be promoted sufficiently,
As a result, the choke valve opens slowly, the warm-up time becomes longer, fuel economy deteriorates significantly, the interior of the vehicle is not sufficiently heated, and the comfort of the interior of the vehicle is impaired. On the other hand, while the vehicle is running, it is desirable for the engine speed to be low; if this is set high, the vehicle speed may not drop for a while while driving or decelerating, or if the engine speed is In the case of a vehicle, when stopping at D 7 lunge, the rotational speed is high, so it may not be possible to stop, and there is a possibility that the vehicle may start suddenly.

〔発明の目的〕[Purpose of the invention]

本発明は上記に鑑みてなされたもので、その目的とする
ところは、車輛の定置暖機中は、内燃機関の回転数を充
分高く設定することができ、かつ、走行暖機中は、必要
以上に機関回転数が上らないようにできるオートチョー
ク式の気化器を提供することにある。The present invention has been made in view of the above, and its purpose is to be able to set the rotational speed of the internal combustion engine sufficiently high while the vehicle is being warmed up in a stationary position, and to be able to set the revolution speed of the internal combustion engine sufficiently high while the vehicle is being warmed up. An object of the present invention is to provide an auto-choke type carburetor which can prevent the engine speed from increasing more than the above level.

〔発明の概要〕[Summary of the invention]

本発明の特徴は、同一軸を中心として回動可能に感温部
材で駆動される第１のカムのほかに第２のカムを設け、
上記第１のカムと上記第２のカムとはばね部材によって
お互いに引き寄せ合う状態に保持し、上記第１のカムに
は上記第２のカムの回動を制限する回動阻止部材を固定
し、上記第２のカムには上記第１．第２のカムのカム面
に接触して絞弁の開弁機構を回動させるローラー部材の
動きを阻止する突起部を設けた構成とした点にある。The present invention is characterized by providing a second cam in addition to the first cam rotatably driven by a temperature-sensitive member about the same axis,
The first cam and the second cam are held in a state where they are attracted to each other by a spring member, and a rotation prevention member that restricts rotation of the second cam is fixed to the first cam. , the second cam has the first cam. The present invention has a structure in which a protrusion is provided that contacts the cam surface of the second cam and prevents movement of a roller member that rotates the valve opening mechanism of the throttle valve.

〔発明の実施例〕[Embodiments of the invention]

以下本発明を第１図に示した実施例および第２図〜第７
図を用いて詳細に説明する。The embodiment of the present invention shown in FIG. 1 and FIGS. 2 to 7 are as follows.
This will be explained in detail using figures.

第１図は本発明の気化器の一実施例を示す要部構成説明
図である。第１図において、気化器１の絞弁２の開度は
、絞弁軸３に固定されたアクセルレバ−４またはローラ
ー部材５を有するプレート６の回動量によって設定され
る。そしてローラー部利５は、内燃機関の暖機中は第１
のカム７または第２のカム８のカム面と当接している。FIG. 1 is an explanatory diagram of the main part configuration of an embodiment of the vaporizer of the present invention. In FIG. 1, the opening degree of a throttle valve 2 of a carburetor 1 is set by the amount of rotation of an accelerator lever 4 fixed to a throttle valve shaft 3 or a plate 6 having a roller member 5. The roller section profit 5 is the first during warm-up of the internal combustion engine.
cam 7 or the cam surface of the second cam 8.

第１のカム７は従来から設けられているもので、一端が
気化器１の本体のボス９に固定してアシ、他端が第１の
カム７のばね掛は部１０に固定された第１のばね部材１
１によって常に右廻シ（時計の針の回動方向）の方向へ
付勢されている。一方、第２のカム８は新たに設けたも
ので、一端が第１のカム７のばね掛は部１２に固定され
、他端が第２のカム８のばね掛は部１３に固定された第
２のばね部１４によって左廻シの方向へ付勢されている
が、第１のカム７に設は九回動停止部材１５によシ左廻
シの回動が阻止されている。なお、１６は第１のカム７
と第２のカム８の回動中心となるカム軸である。また、
第２のカム８には、突起部１７が設けてあシ、突起部１
７がローラー部材５に係合したときは第２のカム８の左
＠シの回動が阻止されるようにしである。The first cam 7 is conventionally provided, and one end is fixed to the boss 9 of the main body of the carburetor 1, and the other end is a spring hook fixed to the part 10. 1 spring member 1
1, it is always biased in the clockwise direction (rotational direction of the clock hands). On the other hand, the second cam 8 is newly provided, and one end of the spring catch of the first cam 7 is fixed to part 12, and the other end of the spring catch of the second cam 8 is fixed to part 13. Although it is biased in the counterclockwise direction by the second spring portion 14, the counterclockwise rotation is prevented by a nine-turn stop member 15 provided on the first cam 7. In addition, 16 is the first cam 7
and a cam shaft that is the center of rotation of the second cam 8. Also,
The second cam 8 is provided with a protrusion 17.
When the second cam 7 engages with the roller member 5, the second cam 8 is prevented from rotating to the left.

一方、感温部材１８の一部品であるプランジャー１９は
、感温部材１８の動作特性に応じて左右に摺動運動を行
い、その先端は第１のカム７に固定しである調節ネジ２
０の先端に当接させてあシ、感温部材１８と第１のばね
部材１１との力関係によって第１のカム７の回動位置が
定まるようにしである。On the other hand, the plunger 19, which is a part of the temperature sensing member 18, slides left and right depending on the operating characteristics of the temperature sensing member 18, and its tip is fixed to the first cam 7, which is an adjustment screw 2.
The rotating position of the first cam 7 is determined by the force relationship between the temperature sensing member 18 and the first spring member 11.

なお、チョーク弁２１の開度は、第１のカム７のばね掛
は部１０に当接して第１のカムと同時にカム軸１６のま
わシを回動するコネクタプレート２２、チョークリンク
２３、チョークレバー２４、チョークばね２５を介して
最適に設定されるようになっている。。Note that the opening degree of the choke valve 21 is determined by the connector plate 22, the choke link 23, and the choke valve 21, which are in contact with the spring-loaded portion 10 of the first cam 7 and rotate the camshaft 16 at the same time as the first cam. It is designed to be optimally set via a lever 24 and a choke spring 25. .

次に、上記した構成の気化器の作用と効果按第２図〜第
５図および第６図、第７図を用いて説明する。Next, the operation and effects of the vaporizer having the above-described structure will be explained using FIGS. 2 to 5, and FIGS. 6 and 7.

低温始動時には、第２図に示す如く、感温部材１８は収
縮しているので、寸法りは小さくなっておシ、第１のカ
ム７は第１のばね部材１１の作用によシ大きく右廻９に
回動している。このとき、ローラー部材５は第１のカム
７のカム面に当接しているので、絞弁２の開度は、第７
図の０点の如く大きく設定される。なお、このときは、
第２のカム８は、回動停止部材１５のため左廻りの回動
が阻止されておシ、図示しであるように、ローラー部材
５は第２のカム８のカム面には当接しない。When starting at a low temperature, as shown in FIG. It is rotating around 9. At this time, since the roller member 5 is in contact with the cam surface of the first cam 7, the opening degree of the throttle valve 2 is
It is set to a large value like the 0 point in the figure. In addition, at this time,
The second cam 8 is prevented from rotating counterclockwise by the rotation stopping member 15, and the roller member 5 does not come into contact with the cam surface of the second cam 8, as shown in the figure. .

そして、内燃機関の暖機が進むにつれて、感温部材１８
が伸びるので寸法りが次第に大きくなシ、第１のカム７
は次第に左廻ルに回動し、ローラー部材５が第２のカム
８のカム面に当接するようになシ、遂には第３図に示す
状態となり、第２のカム８の突起部１７にローラー部材
５が当接するようになる。この場合は、第２のばね部材
１４の付勢力の増大にかかわらず、第２のカム８は左廻
シの回動をローラー部材５によって阻止される。このと
きの絞弁２の開度の変化は、ローラー部材５が第２のカ
ム８のカム面に当接した時点では、第７図のＡ点で、そ
の後、内燃機関の暖機が進むにしたがい、Ｂ点、０点と
第２のカム８が等径カムであれば暖気の進行にかかわら
ず一定に保持され、突起部１７とローラー部材５との当
接後はそのときの状態が保持される。したがって、機関
回転数も第６図に１点鎖線ａで示しであるように高く設
定される。As the internal combustion engine warms up, the temperature sensing member 18
As the first cam 7 expands, its dimensions gradually become larger.
gradually rotates counterclockwise until the roller member 5 comes into contact with the cam surface of the second cam 8, and finally reaches the state shown in FIG. The roller member 5 comes into contact. In this case, the second cam 8 is prevented from rotating counterclockwise by the roller member 5, regardless of the increase in the biasing force of the second spring member 14. At this time, the opening degree of the throttle valve 2 changes at point A in FIG. 7 when the roller member 5 comes into contact with the cam surface of the second cam 8, and thereafter as the internal combustion engine warms up. Therefore, if point B, point 0, and the second cam 8 are equal-diameter cams, they will be held constant regardless of the progress of warm air, and the state at that time will be maintained after the protrusion 17 and the roller member 5 come into contact. be done. Therefore, the engine speed is also set high as shown by the dashed line a in FIG.

一方、第３図相当の暖機中に人為的にアクセル操作をし
てアクダルレバー４を第４図の矢印方向に回動させる力
を加えると、プレート６が圧廻シに回動し、ローラー部
材５は、第２のカム８のカー　広面および突起部１７か
ら当接を解除され、第４図に示しであるように、第２の
カム８は、第２のばね部材１４の作用で第１のカム７に
設けた回動停止部材１５に当接するまで左廻シに回動す
る。On the other hand, when the accelerator is manually operated during warm-up as shown in Fig. 3 and a force is applied to rotate the accelerator lever 4 in the direction of the arrow in Fig. 4, the plate 6 rotates in the pressure direction, and the roller member 5 is released from contact with the wide surface of the second cam 8 and the projection 17, and as shown in FIG. The cam 7 rotates counterclockwise until it comes into contact with a rotation stop member 15 provided on the cam 7.

さらに、この状態でアクセル操作を解除すると、第５図
に示すようになシ、例えば、絞弁２の開度は通常のアイ
ドル開度に設定されるようにローラー部材５は第１のカ
ム７のカム面に接触し、第２のカム８のカム面に当接し
ない状態とな弘絞弁開度は第７図の０点から０７点に移
動し、機関回転数は第６図の０点から０７点に変わシ、
正常に設定される。Furthermore, when the accelerator operation is released in this state, as shown in FIG. The throttle valve opening moves from point 0 in Fig. 7 to point 07 in Fig. 7, and the engine speed changes to 0 in Fig. 6. The point changed to 07 points,
It is set correctly.

なお、内燃機関の暖機状態がまだ不充分なときにアクセ
ル操作を行って走行状態に入ったときは、絞弁開度およ
び機関回転数がそれぞれ第７図、第６図のＢ点からＢ′
点に変わるが、前段階で第２のカム８の作用によシ充分
暖機が促進されているので、内燃機関の運転状態は良好
に確保される。Note that if the internal combustion engine is not sufficiently warmed up and the accelerator is operated to start running, the throttle valve opening and the engine speed will change from point B to point B in Figures 7 and 6, respectively. ′
However, since warm-up is sufficiently promoted by the action of the second cam 8 in the previous stage, a good operating condition of the internal combustion engine is ensured.

また、第１図において、第２のカム８のカム形状は、カ
ム軸１６からの距離が第１のカム７のカム軸１６からの
最大距離よｐ小さく、最小距離よシ大きい範囲の点を連
続的に接続した面形状とし対 であるが、上記したように軸心につして等径カムとして
もよく、まに１例えば、絞弁開度が第７図のＡ−Ｄ−Ｅ
となるように上記の範囲で不等径の度合を任意に変えて
もよいことはいうまでもない。In addition, in FIG. 1, the cam shape of the second cam 8 has a point in a range where the distance from the cam shaft 16 is p smaller than the maximum distance from the cam shaft 16 of the first cam 7 and larger than the minimum distance. They are a pair of continuously connected surface shapes, but as mentioned above, cams of equal diameter around the axis may also be used.For example, once the throttle valve opening is A-D-E in
It goes without saying that the degree of unequal diameter may be arbitrarily changed within the above range so that

上記したように、本発明においては、感温部材１８によ
シ自動で回動される第１のカム７は、主として走行暖機
中の絞弁開度制御用に使用し、車輛の定置暖機中の絞弁
開度の制御は新たに設けた第２のカム８で行うようにし
た。そのため、第１のカム７のカム面は走行暖機に最適
な形状とし、第２のカム８のカム面は定置暖機に最適な
形状とした。また、動作は、始動時にはローラー部材５
が第１のカム７のカム面に当接し、絞弁開度を始動に最
適に設定し、その後所定の時間は、感温部材１８によシ
第１のカム７が回動され、絞弁開度は第１のカム７のカ
ム面に応じて変化する。さらに暖機が促進されると、ロ
ーラー部材５が第２のカム８のカム面に当接し、第１の
カム７のカム面との当接は解除される。この時間帯では
、絞弁開度は第２のカム８のカム面に応じて変化する。As described above, in the present invention, the first cam 7, which is automatically rotated by the temperature sensing member 18, is mainly used for controlling the opening of the throttle valve during warm-up while the vehicle is being warmed up. The opening of the throttle valve inside the machine is controlled by a newly installed second cam 8. Therefore, the cam surface of the first cam 7 has a shape optimal for running warm-up, and the cam surface of the second cam 8 has a shape optimal for stationary warm-up. In addition, the operation is performed by the roller member 5 at the time of startup.
contacts the cam surface of the first cam 7 to optimally set the opening of the throttle valve for starting, and then for a predetermined period of time, the first cam 7 is rotated by the temperature sensing member 18 and the throttle valve is opened. The opening degree changes depending on the cam surface of the first cam 7. When warm-up is further promoted, the roller member 5 comes into contact with the cam surface of the second cam 8, and the contact with the cam surface of the first cam 7 is released. During this time period, the throttle valve opening degree changes according to the cam surface of the second cam 8.

ここで、第２のカム８には、ローラー部材５と第２のカ
ム８との相互回動を阻止する突起部１７が設けであるの
で、人為的にローラー部材５が第２のカム７のカム面か
ら当接を解除されない限シ、絞弁開度は第２のカム８の
カム面で設定され、定置暖機に最適な絞弁開度の制御が
可能となる。さらに、一旦、アクセル操作が人為的に行
われると、第２のカム８は第２のばね部材１４によシ回
動されるので、再びアクセル操作が解除されたとき、ロ
ーラー部材５が当接する面は、第１のカム７のカム面と
なる。したがって、走行中は、アクセル操作が繰シ返さ
れるので、絞弁開度は第１のカム７のカム面に応じて変
化し、走行状態に適した絞弁開度の制御が可能となる。Here, since the second cam 8 is provided with a protrusion 17 that prevents mutual rotation of the roller member 5 and the second cam 8, the roller member 5 is artificially moved from the second cam 7. As long as the contact is not released from the cam surface, the throttle valve opening degree is set by the cam surface of the second cam 8, making it possible to control the throttle valve opening degree optimal for stationary warm-up. Further, once the accelerator operation is performed manually, the second cam 8 is rotated by the second spring member 14, so that when the accelerator operation is released again, the roller member 5 comes into contact with the second cam 8. The surface becomes the cam surface of the first cam 7. Therefore, since the accelerator operation is repeated while the vehicle is running, the throttle valve opening degree changes in accordance with the cam surface of the first cam 7, making it possible to control the throttle valve opening degree suitable for the driving condition.

〔発明の効果〕〔Effect of the invention〕

以上説明したように、本発明によれば、車輛の定置暖機
中は、内燃機構の回転数を充分高く設定できるので暖機
を充分促進することが可能で、かつ、走行暖機中は、必
要以上に機関回転数が上らないようにできるので停車中
に突然発進するという不具合等が発生しないようにする
ことが可能であるという効果がある。As explained above, according to the present invention, the rotational speed of the internal combustion mechanism can be set sufficiently high while the vehicle is being warmed up in a stationary position, so that warming up can be sufficiently promoted, and while the vehicle is being warmed up while the vehicle is being warmed up, Since it is possible to prevent the engine speed from increasing more than necessary, it is possible to prevent problems such as the sudden start of the vehicle while the vehicle is stopped.

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

第１図は本発明の気化器の一実施例を示す要部構成説明
図、第２図〜第５図は第１図の気化器の動作を説明する
ための各種の状態説明図、第６図。 第７図はそれぞれ機関暖気中の機関回転数および絞弁開
度を示す線図である。 １・・・気化器、２・・・絞弁、４・・・アクセルレバ
−１５・・・ローラー部材、６・・・プレート、７・・
・第１のカム、８・・・第２のカム、１１・・・第１の
ばね部材、１４・・・第２のばね部材、１５・・・回動
停止部材、１６・・・カム軸、１７・・・突起部、１７
・・・感温部材、１８・・・プランジャー、１９・・・
調節ネジ、２０・・・チョーク弁。 第　１　口FIG. 1 is an explanatory diagram of the main part configuration showing one embodiment of the carburetor of the present invention, FIGS. 2 to 5 are explanatory diagrams of various states for explaining the operation of the carburetor of FIG. 1, and FIG. figure. FIG. 7 is a diagram showing the engine speed and throttle valve opening during engine warm-up. DESCRIPTION OF SYMBOLS 1... Carburetor, 2... Throttle valve, 4... Accelerator lever 15... Roller member, 6... Plate, 7...
・First cam, 8... Second cam, 11... First spring member, 14... Second spring member, 15... Rotation stop member, 16... Cam shaft , 17... protrusion, 17
...Temperature-sensitive member, 18...Plunger, 19...
Adjustment screw, 20...Choke valve. 1st mouth

Claims (1)

【特許請求の範囲】 １、内燃機関の暖機状態を感知してチョーク弁および絞
弁の開度を自動的に制御する機構を備えた気化器におい
て、同一カム軸を中心として回動可能に感温部材で駆動
埒れる第１のカムのほかに第２のカムを設け、前記第１
のカムと前記第２のカムとはばね部材によってお互いに
引き寄せ合う状態に保持し、前記第１のカムには前記第
２のカムの回動を制限する回動阻止部材を固定し、前記
第２のカムには前記第１．第２のカムのカム面に埃触し
て前記絞弁の開弁機構を回動させるローラー部材の動き
を阻止する突起Ｗ１５を設けた構成としたことを特徴と
する気化器。 ２、前記第２のカムのカム面は、前記カム軸からの距離
が前記第１のカムの前記カム軸からの最大距離より小さ
く、最小距離よシ大きい範囲の点を連続的に接続した形
状としである特許請求の範囲第１項記載の気化器。 ３、前記内燃機関の暖気が所定値まで進んで前記ローラ
ー部材が前記第２のカムのカム面に当接した状態では、
前記感温部材による前記第１のカムの回動に関係なく前
記絞弁の開度が前記第２のカムのカム面の形状によって
設定され、前記第２のカムの突起部と前記ローラー部材
との係合は前記絞弁の開弁機構が人為操作によって駆動
されると解除され、その後の前記絞弁の開度は前記第１
のカムのカム面の形状によって設定されるように構成し
である特許請求の範囲第１項または第２項記載の気化器
。[Claims] 1. A carburetor equipped with a mechanism that detects the warm-up state of an internal combustion engine and automatically controls the opening degrees of a choke valve and a throttle valve, which can be rotated around the same camshaft. A second cam is provided in addition to the first cam that is driven by a temperature sensing member, and
The cam and the second cam are held in a state where they are attracted to each other by a spring member, and a rotation prevention member is fixed to the first cam to limit the rotation of the second cam. The second cam has the first cam. A carburetor characterized in that a protrusion W15 is provided that contacts the cam surface of the second cam with dust and prevents movement of a roller member that rotates the valve opening mechanism of the throttle valve. 2. The cam surface of the second cam has a shape in which a distance from the cam shaft is smaller than the maximum distance from the cam shaft of the first cam and continuously connects points that are larger than the minimum distance. A vaporizer according to claim 1, which is a carburetor. 3. In a state where the internal combustion engine has warmed up to a predetermined value and the roller member is in contact with the cam surface of the second cam,
The opening degree of the throttle valve is set by the shape of the cam surface of the second cam regardless of the rotation of the first cam by the temperature sensing member, and the protrusion of the second cam and the roller member The engagement of the throttle valve is released when the valve opening mechanism of the throttle valve is driven by manual operation, and the opening degree of the throttle valve thereafter is the same as that of the first throttle valve.
The carburetor according to claim 1 or 2, wherein the carburetor is configured to be set by the shape of the cam surface of the cam.