JPH03145566A - Fuel feeding device for engine - Google Patents

Fuel feeding device for engine

Info

Publication number
JPH03145566A
JPH03145566A JP1282580A JP28258089A JPH03145566A JP H03145566 A JPH03145566 A JP H03145566A JP 1282580 A JP1282580 A JP 1282580A JP 28258089 A JP28258089 A JP 28258089A JP H03145566 A JPH03145566 A JP H03145566A
Authority
JP
Japan
Prior art keywords
fuel
pressure
negative pressure
chamber
valve
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
JP1282580A
Other languages
Japanese (ja)
Other versions
JP2791432B2 (en
Inventor
Yoshiya Kamozawa
鴨沢 凱也
Yoichi Sato
庸一 佐藤
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.)
Nippon Carburetor Co Ltd
Original Assignee
Nippon Carburetor Co 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 Nippon Carburetor Co Ltd filed Critical Nippon Carburetor Co Ltd
Priority to JP1282580A priority Critical patent/JP2791432B2/en
Publication of JPH03145566A publication Critical patent/JPH03145566A/en
Application granted granted Critical
Publication of JP2791432B2 publication Critical patent/JP2791432B2/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

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  • Fuel-Injection Apparatus (AREA)
  • Control Of The Air-Fuel Ratio Of Carburetors (AREA)

Abstract

PURPOSE:To improve low-temperature startability and warm-up operability by providing a low temperature augmentation mechanism which moves a diaphragm to a pressure regulating chamber side to largely open a pressure regulator and increases the fuel pressure of the pressure regulating chamber when the temperature is low on a fuel pressure regulator. CONSTITUTION:A fuel pressure regulator 25 and a fuel flow regulator 55 are provided on the outside face of a main body 1 provided with a fixed Venturi 3 and a throttle valve 4 on an intake path 2 extended in the vertical direction in this device. The fuel pressure regulator 25 feeds the fuel regulated to the nearly constant positive pressure to a main nozzle 48 with a variable effective area via a metering needle 79, and the fuel flow regulator 55 operates the metering needle 79 in response to the difference between the Venturi negative pressure and the intake negative pressure. A low-temperature augmentation mechanism 52 penetrated with a rod 46 on the free end section of a cantilever- supported bimetal 44 through a barrel 38 into contact with a diaphragm 37 is provided on the fuel pressure regulator 25, ana a pressure regulating valve 26 is largely opened at a low temperature.

Description

【発明の詳細な説明】 [産業上の利用分野] 本発明は小排気量のエンジンに燃料(ガソリン)を供給
する装置に関するものである。
DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an apparatus for supplying fuel (gasoline) to a small displacement engine.

[従来の技術] 小形車両、産業機械、発電機などを駆動する比較的小排
気量のエンジンに燃料を供給する手段として広く用いら
れている気化器の内で、固定ベンヂュリ気化器は低速燃
料と主燃料とを別通路で供給するので燃料のつながりが
不安定になりやすいとともに通路構成が複雑であり、可
変ベンチュリ気化器はベンチュリピストンとその案内な
どきわめて高い加工精度を要求する個所が多い、などの
問題をもっている。また、燃料調整手段が浮子式のもの
は大きな傾斜に対応できず、模式のものはさまざまな姿
勢に対応できる反面燃料の制御精度がよくない、などの
問題がある。
[Prior Art] Among the carburetors that are widely used as a means of supplying fuel to relatively small displacement engines that drive small vehicles, industrial machinery, generators, etc., fixed venturi carburetors are used for low-speed fuel and Because the main fuel is supplied through a separate passage, the fuel connection tends to be unstable and the passage configuration is complicated.Variable venturi carburetors have many parts that require extremely high machining precision, such as the venturi piston and its guide. I have a problem. In addition, a float-type fuel adjustment means cannot cope with large inclinations, and a model-type one can cope with various postures, but the accuracy of fuel control is poor.

一方、ベンチュリ負圧などで燃料を吸気路に吸出す前記
の気化器に対して、第二次世界大戦中に航空機エンジン
用気化器の結氷対策とじて実用化されたいわゆる噴射気
化器がある。この気化器はペンデイックス社製のストロ
ンバーブ型気化器が広く知られており、ベンチュリ入口
動圧とベンチュリ負圧との差圧力で駆動される燃料圧力
制御弁、絞り弁に連動する燃料流量制御弁、ベンチュリ
負圧で駆動される燃料噴射弁を経て燃料を正圧力で吸気
路に噴射するものである。
On the other hand, in contrast to the above-mentioned carburetor that sucks fuel into the intake passage using a venturi negative pressure, there is a so-called injection carburetor that was put into practical use during World War II as a countermeasure against freezing in aircraft engine carburetors. The Strombarb type carburetor manufactured by Pendex is widely known as this carburetor, and the fuel pressure control valve is driven by the differential pressure between the venturi inlet dynamic pressure and the venturi negative pressure, and the fuel flow control valve is linked to the throttle valve. , fuel is injected into the intake passage at positive pressure via a fuel injection valve driven by venturi negative pressure.

そして、このようないわゆる噴射気化器はさまざまな姿
勢に対して燃料の制御精度が高いという利点をもってい
る反面、燃料通路に前記三つの弁が直列に配置され、更
に始動や加速のための燃料供給手段が別途に設けられて
いるため燃料系統がきわめて複雑であるという欠点をも
っているのを改善し、燃料通路には燃料圧力調整手段の
みを配置した構成の燃料供給装置が特開平1−3203
1号公報に開示されている。
Although such a so-called injection carburetor has the advantage of highly accurate fuel control in various postures, the three valves mentioned above are arranged in series in the fuel passage, and the fuel supply for starting and acceleration is difficult. Japanese Patent Laid-Open No. 1-3203 discloses a fuel supply device having a structure in which only a fuel pressure regulating means is disposed in the fuel passage, which improves the drawback that the fuel system is extremely complicated due to the provision of a separate means.
It is disclosed in Publication No. 1.

前記公報に開示されている技術は本発明の発明者、特許
出願人が提供したものであって、燃料をほぼ一定の正圧
力に調整して吸気路へ開口した主ノズルに送る燃料圧力
調整器と、ベンチュリ負圧と吸気マニホルド負圧との差
圧力に応じて主ノズルの有効面積を変える計量ニードル
を動作させエンジン吸気量に応じて有効面積を増減させ
る燃料流量調整器とを具えている。
The technology disclosed in the above-mentioned publication was provided by the inventor and patent applicant of the present invention, and is a fuel pressure regulator that adjusts fuel to a substantially constant positive pressure and sends it to a main nozzle that opens into an intake passage. and a fuel flow regulator that operates a metering needle that changes the effective area of the main nozzle in response to the differential pressure between the venturi negative pressure and the intake manifold negative pressure to increase or decrease the effective area in accordance with the engine intake air amount.

ところが、燃料圧力調整器は燃料を常にほぼ一定の正圧
力とし、燃料流量調整器はエンジン吸気量に応じてエン
ジンに供給される燃料流量を制御するだけであるので、
温度によって燃料流量を補正する手段がなく、低温時に
要求される燃料増量に対応することができない。
However, the fuel pressure regulator always keeps the fuel at a nearly constant positive pressure, and the fuel flow regulator only controls the fuel flow rate supplied to the engine according to the engine intake air amount.
There is no means to correct the fuel flow rate depending on the temperature, and it is not possible to respond to the increase in fuel required at low temperatures.

[発明が解決しようとする課題] 本発明は二のように燃料圧力をほぼ一定とするだけの燃
料圧力調整器や燃料流量をエンジン吸気量に応じて制御
するだけの燃料流量調整器では低温時の増量ができない
という前記技術がもっている課題を解決しようとするも
のであって、燃料圧力を低温時に高くすることによって
燃料増量を計り低温始動性および暖機運転性を向上させ
ることができる燃料供給装置を提供することを目的とす
る。
[Problems to be Solved by the Invention] The present invention, as described in item 2, has problems with a fuel pressure regulator that only keeps the fuel pressure almost constant or a fuel flow regulator that only controls the fuel flow rate in accordance with the engine intake air amount. This technology aims to solve the problem that the above-mentioned technology has that it is not possible to increase the amount of fuel, and the fuel supply is capable of increasing the amount of fuel by increasing the fuel pressure at low temperatures and improving low-temperature startability and warm-up performance. The purpose is to provide equipment.

[課題を解決するための手段] 本発明は固定ベンチュリおよび絞り弁を有する吸気路と
、前記吸気路に開口し計量ニードルにより有効面積が可
変の主ノズルと、燃料をほぼ一定の正圧力に調整して前
記主ノズルに送る燃料圧力調整器と、ベンチュリ負圧と
絞り弁の側方またはその下流側の吸気負圧との差圧力に
応じて前記計量ニードルを動作させエンジン吸気量にほ
ぼ対応して前記主ノズルの有効面積を変化させる燃料調
整器とを具えており、前記燃料圧力調整器は燃料をほぼ
一定の正圧力に維持させる調圧室と、大気室と、前記二
つの室を仕切ったダイヤフラムと、前記大気室に装入さ
れて前記ダイヤフラムを前記調圧室の方へ押す調圧ばね
と、前記調圧室に接続された燃料導入路を前記ダイヤフ
ラムの位置に応じて開閉する圧力調整弁とから構成され
ているエンジンの燃料供給装置がもっている前記課題を
解決するため次の手段を講じた。
[Means for Solving the Problems] The present invention includes an intake passage having a fixed venturi and a throttle valve, a main nozzle that opens into the intake passage and whose effective area is variable with a metering needle, and adjusts the fuel to a substantially constant positive pressure. and a fuel pressure regulator that sends the fuel to the main nozzle, and operates the metering needle in accordance with the differential pressure between the venturi negative pressure and the intake negative pressure on the side of the throttle valve or downstream thereof, so as to approximately correspond to the engine intake air amount. and a fuel regulator that changes the effective area of the main nozzle, and the fuel pressure regulator partitions the two chambers into a pressure regulating chamber that maintains the fuel at a substantially constant positive pressure, an atmospheric chamber, and an atmospheric chamber. a pressure regulating spring that is inserted into the atmospheric chamber and pushes the diaphragm toward the pressure regulating chamber, and a pressure that opens and closes a fuel introduction path connected to the pressure regulating chamber depending on the position of the diaphragm. In order to solve the above-mentioned problem of the engine fuel supply system which is composed of a regulating valve, the following measures have been taken.

即ち、温度が高いとき前記ダイヤフラムを正常な位置で
動作させるが、温度が低いとき前記ダイヤフラムを前記
調圧室の方へ移動させ前記圧力調整弁を大きく開いて調
圧室の燃料圧力を高くするように働く低温増量機構を設
けた。
That is, when the temperature is high, the diaphragm is operated at a normal position, but when the temperature is low, the diaphragm is moved toward the pressure regulating chamber and the pressure regulating valve is wide open to increase the fuel pressure in the pressure regulating chamber. We have installed a low temperature increase mechanism that works like this.

[作用] 燃料圧力調整器に付設した低温増量機構は温度が高いと
きダイヤフラムに作用せず、圧力調整弁は調圧室の燃料
を設定圧力に維持させるように動作している。温度が低
いときダイヤフラムは調圧室の方へ移動させられて圧力
調整弁を強制的に大きく開き、燃料を調圧室に大量に導
入して燃料圧力を高くする。その結果、主ノズルからエ
ンジンに供給される燃料が増量されることとなるのであ
る。
[Operation] The low temperature increase mechanism attached to the fuel pressure regulator does not act on the diaphragm when the temperature is high, and the pressure regulating valve operates to maintain the fuel in the pressure regulating chamber at the set pressure. When the temperature is low, the diaphragm is moved toward the pressure regulating chamber, forcing the pressure regulating valve to open wide, introducing a large amount of fuel into the pressure regulating chamber, and increasing the fuel pressure. As a result, the amount of fuel supplied to the engine from the main nozzle is increased.

[実施例] 図面を参照して本発明の詳細な説明する。[Example] The present invention will be described in detail with reference to the drawings.

本体lの竪方向へ延びる単一の吸気路2に固定ベンチュ
リ3と絞り弁4とが設置されているとともに、この本体
lの外側面に燃料ポンプ5、燃料圧力調整器25、燃料
流量調整器55が設けられている。
A fixed venturi 3 and a throttle valve 4 are installed in a single intake passage 2 extending in the vertical direction of the main body l, and a fuel pump 5, a fuel pressure regulator 25, and a fuel flow regulator are installed on the outer surface of the main body l. 55 are provided.

燃料ポンプ5は第5図を参照して、本体lの一つの側面
にダイヤフラムからなるポンプ膜6、ポンプ胴体7、ダ
イヤフラムからなる仕切膜8、カバニ9を順に重ねて止
ねじにより一体に締付は固定し、本体lとポンプ膜6と
の間をポンプばねlOが装入されたパルス室11.ポン
プ膜6とポンプ胴体7との間をポンプ室12、ポンプ胴
体7と仕切膜8との間を吸込室13および吐出室I4、
仕切膜8とカバー9との間を大気室15としたよく知ら
れているパルス式ダイヤフラムポンプであって、エンジ
ンのクランクケースに発生したパルス圧をパルス圧通路
16によってパルス室11に導入しポンプ膜6を往復動
させて燃料人口17から吸込室13に入った燃料を入口
逆止弁18よリポンプ室12に吸込み、次で出口逆止弁
19より吐出室14に吐出することも従来のものと同じ
である。尚、入口逆止弁18と出口逆止弁19はゴム板
で作られ、ポンプ胴体7にリベット20によって片持ち
式に支持されている。
Referring to FIG. 5, the fuel pump 5 has a pump membrane 6 made of a diaphragm, a pump body 7, a partition membrane 8 made of a diaphragm, and a cover 9 stacked one on top of the other in order on one side of a main body l, and then tightened together with a set screw. is fixed, and a pulse chamber 11. is inserted between the main body l and the pump membrane 6 into which a pump spring lO is inserted. A pump chamber 12 is provided between the pump membrane 6 and the pump body 7, a suction chamber 13 and a discharge chamber I4 are provided between the pump body 7 and the partition membrane 8,
This is a well-known pulse type diaphragm pump that has an atmospheric chamber 15 between a partition membrane 8 and a cover 9, and the pulse pressure generated in the engine crankcase is introduced into the pulse chamber 11 through a pulse pressure passage 16. It is also conventional to reciprocate the membrane 6 to suck the fuel that has entered the suction chamber 13 from the fuel port 17 into the re-pump chamber 12 through the inlet check valve 18 and then discharge it into the discharge chamber 14 through the outlet check valve 19. is the same as Incidentally, the inlet check valve 18 and the outlet check valve 19 are made of rubber plates, and are supported on the pump body 7 by rivets 20 in a cantilevered manner.

燃料圧力調整器25は第5.6図を参照して、本体1の
前記とは別の側面に配置された圧力調整弁26と調圧室
36とを有している。圧力調整弁26は燃料ポンプ5の
吐出室14と燃料導入路2Iによって接続された弁室2
7、弁室27に装入された弁体28および弁ばね29、
弁座30を有しており。
Referring to FIG. 5.6, the fuel pressure regulator 25 has a pressure regulating valve 26 and a pressure regulating chamber 36 arranged on a side surface of the main body 1 different from the above. The pressure regulating valve 26 is a valve chamber 2 connected to the discharge chamber 14 of the fuel pump 5 by a fuel introduction passage 2I.
7. Valve body 28 and valve spring 29 inserted into valve chamber 27;
It has a valve seat 30.

弁室27と調圧室36とを連通する弁座口31が弁体2
8によって開閉される。弁体28の後方へ延びる案内桁
32は気化器本体1に固着されて弁室27を塞いだプラ
グ33の案内孔34に密嵌して弁体28を直線往復動さ
せ、弁体28の前方へ延びる作動桁35は弁座口31を
緩く貫通して調圧室36に突出しダイヤフラム37に接
している。このダイヤフラム37は本体lに調整器胴体
38と重ねて一体に固定されており、ダイヤフラム37
と調整器胴体38との間は大気室39を形成し調圧ばね
40が装入されている。
The valve seat opening 31 that communicates the valve chamber 27 and the pressure regulating chamber 36 is connected to the valve body 2.
It is opened and closed by 8. A guide spar 32 extending toward the rear of the valve body 28 is tightly fitted into a guide hole 34 of a plug 33 that is fixed to the carburetor body 1 and closes the valve chamber 27, causing the valve body 28 to reciprocate in a straight line. The operating girder 35 extending to the valve seat opening 31 loosely passes through the valve seat opening 31 , projects into the pressure regulating chamber 36 , and comes into contact with the diaphragm 37 . This diaphragm 37 is fixed to the main body l overlapping with the regulator body 38, and the diaphragm 37
An atmospheric chamber 39 is formed between the regulator body 38 and the regulator body 38, and a pressure regulating spring 40 is inserted therein.

圧力調整弁26の弁体28は調圧室36の燃料圧力と弁
ばね29および調圧ばね40のばね荷重とによって定ま
るダイヤフラム37の位置に応じて弁座口31を開閉す
るものであって、調圧室36の燃料圧力が高くなると閉
弁し低くなると開弁して燃料ポンプ5から弁室27に送
られてきた燃料を予め設定した0、05〜0.2kg/
cm程度の範囲内の一定正圧力に調整し、調圧室36の
燃料をこの範囲内の正圧力に維持する。
The valve body 28 of the pressure regulating valve 26 opens and closes the valve seat port 31 according to the position of the diaphragm 37 determined by the fuel pressure in the pressure regulating chamber 36 and the spring loads of the valve spring 29 and the pressure regulating spring 40. When the fuel pressure in the pressure regulating chamber 36 increases, the valve closes, and when it decreases, the valve opens, and the fuel sent from the fuel pump 5 to the valve chamber 27 is adjusted to a preset rate of 0.05 to 0.2 kg/
The pressure is adjusted to a constant positive pressure within a range of about cm, and the fuel in the pressure regulating chamber 36 is maintained at a positive pressure within this range.

調整器胴体38の外側には保護カバー41がねじ42に
よって取外し可能に固定してあり、これらに囲まれた空
間は調整器胴体38にねじ43によって片持ち式に取付
けた板状のバイメタル44を内蔵したバイメタル室45
を形成している。このバイメタル44の自由端部はm祭
器胴体38を貫通してダイヤフラム37に接するバイメ
タルロッド46が結合されており、このバイメタル44
、バイメタルロッド46は低温増量機構52を構成して
いる。
A protective cover 41 is removably fixed to the outside of the regulator body 38 with screws 42, and the space surrounded by these covers a plate-shaped bimetal 44 that is cantilevered to the regulator body 38 with screws 43. Built-in bimetal chamber 45
is formed. A bimetal rod 46 is coupled to the free end of this bimetal 44, passing through the m ritual vessel body 38 and contacting the diaphragm 37.
, the bimetal rod 46 constitutes a low temperature increase mechanism 52.

調圧室3Gの燃料は第4.6図を参照して、本体lに形
成された燃料通路47を通り、固定ベンチュリ3の最狭
部に向かって突出した主ノズル(またはニードルジェッ
ト)48の先端から噴射し、吸入空気と混合してエンジ
ンに供給される。
Referring to FIG. 4.6, the fuel in the pressure regulating chamber 3G passes through a fuel passage 47 formed in the main body l, and enters a main nozzle (or needle jet) 48 that protrudes toward the narrowest part of the fixed venturi 3. It is injected from the tip, mixes with intake air, and is supplied to the engine.

燃料通路47は電磁弁49によってエンジンが運転され
ているとき開くがエンジンが停止すると閉じられる。
The fuel passage 47 is opened by a solenoid valve 49 when the engine is running, but is closed when the engine is stopped.

燃料通路47は調圧室36の低い所に開口しており、調
圧室36の最も高い所には図示しない燃料タンクに達す
る戻し通路50が開口している。この戻し通路50は燃
料に含まれている気泡が調圧室36で分#tしたとき、
またはエンジンが停止した後に高い温度のため燃料が蒸
気を発生したとき、これらの空気や燃料蒸気を排出する
ものである。また、エンジン運転中は燃料の一部が戻し
通路50を通って燃料タンクに戻るように、燃料ポンプ
5から調圧室36に送られる燃料流量をエンジン要求量
よりも多くするように設定しておくことにより、殊に燃
料圧力調整器25の温度上昇を抑制することができる0
本実施例では、低温時に増量する燃料やエンジンの高負
荷時に要求される燃料の一部を必要以上に戻し通路50
に流れさせず、且つ空気や燃料蒸気の排出を妨げないよ
うに考慮した絞り51が戻し通路50の入口部分に設け
られている。
The fuel passage 47 opens at a lower part of the pressure regulation chamber 36, and a return passage 50 that reaches a fuel tank (not shown) opens at the highest part of the pressure regulation chamber 36. When the air bubbles contained in the fuel reach the pressure regulating chamber 36,
Or, when the fuel generates steam due to high temperature after the engine has stopped, these air and fuel vapors are discharged. Further, while the engine is operating, the fuel flow rate sent from the fuel pump 5 to the pressure regulating chamber 36 is set to be greater than the amount required by the engine so that a portion of the fuel returns to the fuel tank through the return passage 50. By setting the temperature to 0, it is possible to particularly suppress the temperature rise of the fuel pressure regulator 25.
In this embodiment, a portion of the fuel that increases at low temperatures and the fuel that is required when the engine is under high load is returned to the passage 50 more than necessary.
A throttle 51 is provided at the entrance of the return passage 50 in order to prevent the flow of air and fuel vapor and to prevent the discharge of air and fuel vapor from being obstructed.

次に、第4.5図を参照して、燃料流量調整器55は本
体1の前記とは更に別の側面にダイヤフラム56を挟ん
で固定されたハウジング57と、このハウジング57に
設置した負圧制御弁80とを有している。ダイヤフラム
56のハウジング57側は第一負圧室58を形成し、本
体1側は第二負圧室59を形成しており、第一負圧室5
8は固定ベンチュリ3の最狭部に開口した第一負圧路6
0および絞り99を有していて燃料ポンプ5のパルス室
11に開口した補助負圧路61のいずれかと負圧制御弁
80によって接続される。第二負圧室59はアイドル位
置における絞り弁4の側方で吸気路2に開口しておりそ
して絞り69を有する第二負圧路62が接続されており
、更に第−負正室58と第二負圧室59とにはダイヤフ
ラム56を押す押圧ばね63とバランスばね64とがそ
れぞれ装入されている。
Next, referring to FIG. 4.5, the fuel flow regulator 55 includes a housing 57 fixed to another side of the main body 1 with a diaphragm 56 in between, and a negative pressure installed in the housing 57. It has a control valve 80. The housing 57 side of the diaphragm 56 forms a first negative pressure chamber 58, the main body 1 side forms a second negative pressure chamber 59, and the first negative pressure chamber 5
8 is a first negative pressure path 6 opened at the narrowest part of the fixed venturi 3
0 and an auxiliary negative pressure path 61 having a throttle 99 and opening into the pulse chamber 11 of the fuel pump 5 by a negative pressure control valve 80 . The second negative pressure chamber 59 opens into the intake passage 2 on the side of the throttle valve 4 in the idle position, and is connected to a second negative pressure passage 62 having a throttle 69. A pressure spring 63 and a balance spring 64 that press the diaphragm 56 are inserted into the second negative pressure chamber 59, respectively.

第一負圧路60は第3.4.7図を参照してアイドル位
置における絞り弁4の前記と反対の側方で吸気路2に開
口した第一補正通路65と、固定ベンチュリ3の上流側
で吸気路2に開口した第二抽圧通路67とを有している
。これらの補正通路65.67は絞り66.68をもっ
ており、ベンチュリ負圧が急激に変化しても第一負圧路
60を通って第一負圧室58に入るまでに圧力変化をや
わらげるように働き、その結果ダイヤフラム56は衝撃
的に動かされることがない。
Referring to FIG. 3.4.7, the first negative pressure passage 60 includes a first correction passage 65 that opens into the intake passage 2 on the opposite side of the throttle valve 4 in the idle position, and a first correction passage 65 that opens into the intake passage 2 upstream of the fixed venturi 3. It has a second extraction pressure passage 67 that opens to the intake passage 2 on the side. These correction passages 65 and 67 have throttles 66 and 68, so that even if the venturi negative pressure changes suddenly, the pressure change is softened until it passes through the first negative pressure path 60 and enters the first negative pressure chamber 58. so that the diaphragm 56 is not moved impulsively.

第二負圧室59は第4.8図を参照して、第二負圧路6
2のほかに大気例えば図示しないエアクリーナの内部に
開口した補正通路70が接続されており、この補正通路
70は大気取入れ側で二つに分岐していて、その第一分
岐路71には本体lに外部から手動で調整可能にねじ込
んだ調整ねじ72の先端の針片73が差込まれ、第二分
岐路74には温度弁75が設けられている。温度弁75
は片持ち式の板状のバイメタル76の自由端に取付けた
針状の弁体77を有しており、温度が低いとき弁孔78
を大きく開き温度が高いとき閉じる。
The second negative pressure chamber 59 is connected to the second negative pressure path 6 with reference to FIG. 4.8.
2, a correction passage 70 that opens into the atmosphere, for example, an air cleaner (not shown) is connected, and this correction passage 70 is branched into two on the air intake side, and the first branch passage 71 is connected to the main body l. A needle piece 73 at the tip of an adjustment screw 72 screwed in manually and adjustable from the outside is inserted into the second branch passage 74, and a temperature valve 75 is provided in the second branch passage 74. temperature valve 75
has a needle-shaped valve body 77 attached to the free end of a cantilevered plate-shaped bimetal 76, and when the temperature is low, the valve hole 78
Open wide and close when the temperature is high.

負圧制御弁80は第5.9図を参照して、弁室81、弁
室81の両側に向かい合せに設けた弁座82.83、弁
室81に内蔵された弁体84、戻しばね85を有してお
り、第一の弁座82は第一負圧路60の弁室81への開
口を囲んでいるとともに第二の弁座83は補助負圧路6
1の弁室81への開口を囲んでいる。戻しばね85は弁
体84を第二の弁座83に押付けて補助負圧路61を閉
じ、第一負圧路60を弁室81、出口路86を経て第一
負圧室58に連通させるように働く。
Referring to FIG. 5.9, the negative pressure control valve 80 includes a valve chamber 81, valve seats 82 and 83 facing each other on both sides of the valve chamber 81, a valve body 84 built in the valve chamber 81, and a return spring. 85, the first valve seat 82 surrounds the opening of the first negative pressure path 60 to the valve chamber 81, and the second valve seat 83 surrounds the opening of the first negative pressure path 60 to the valve chamber 81.
It surrounds the opening to the valve chamber 81 of 1. The return spring 85 presses the valve body 84 against the second valve seat 83 to close the auxiliary negative pressure path 61 and connect the first negative pressure path 60 to the first negative pressure chamber 58 via the valve chamber 81 and the outlet path 86. work like that.

第二の弁座83と補助負圧路61の一部とはハウジング
57に固定した案内片87に形成されており、弁体84
から延びるロッド89が補助負圧路61を緩く貫通しそ
の前方で案内片87の案内孔88を気密に貫通して大気
室90に突出している。大気室90はハウジング57の
くぼみによって形成され、その開放端面ばカバー91と
重ねてハウジング57に一体に固定したダイヤフラム9
2によって塞がれているが、空気フィルタ110を有す
る開口111によって大気に連通している(第2図)、
カバー91とダイヤフラム92とに囲まれた部分は負圧
室93を形成し、始動ばね94が装入されているととも
に、吸気路2の絞り弁4よりも下流側の部分と絞り95
を有する負圧通路96によって接続されている。
The second valve seat 83 and a part of the auxiliary negative pressure path 61 are formed on a guide piece 87 fixed to the housing 57, and the valve body 84 is formed on a guide piece 87 fixed to the housing 57.
A rod 89 extending from the auxiliary negative pressure path 61 loosely passes through the guide hole 88 of the guide piece 87 in front thereof in an airtight manner and projects into the atmospheric chamber 90 . The atmospheric chamber 90 is formed by a recess in the housing 57, and the diaphragm 9 is integrally fixed to the housing 57 by overlapping the cover 91 on its open end surface.
2, but communicates with the atmosphere by an opening 111 with an air filter 110 (FIG. 2),
A portion surrounded by the cover 91 and the diaphragm 92 forms a negative pressure chamber 93, in which a starting spring 94 is inserted, and a portion of the intake path 2 downstream of the throttle valve 4 and the throttle 95.
They are connected by a negative pressure passage 96 having a .

燃料流量調整器55のダイヤフラム56の中心部には計
量ニードル79が固着されており、この計量ニードル7
9は第二負圧室59を横切り案内23を貫通して固定ベ
ンチュリ3の反対側に位置する主ノズル48に差込まれ
ている。計量ニードル79の先端の前方には、本体lに
外部から手動で調整可能にねじ込んだねじ97の先端に
設けたストッパ98が主ノズル48の後方において燃料
通路47に突出して設置されている。
A metering needle 79 is fixed to the center of the diaphragm 56 of the fuel flow regulator 55.
9 crosses the second negative pressure chamber 59 , passes through the guide 23 , and is inserted into the main nozzle 48 located on the opposite side of the fixed venturi 3 . In front of the tip of the metering needle 79, a stopper 98 is provided at the tip of a screw 97 screwed into the main body 1 so as to be manually adjustable from the outside and protrudes into the fuel passage 47 behind the main nozzle 48.

計量ニードル79はエンジンの通常の運転状態で第一負
圧路60によって第一負圧室58に導入されたベンチュ
リ負圧、第二負圧路62によって第二負圧室59に導入
された絞り弁4の側方の吸気負圧、押圧ばね63および
バランスばね64の荷重によって定まるダイヤフラム5
6の位置に応じて直線往復動し、主ノズル48の有効面
積を変えてエンジンに供給される燃料流量を変える。即
ち、絞り弁4がアイドル位置のときおよび小開度のとき
第二負圧路62の吸気路2に開口したボート62aには
高い負圧が発生しており、ベンチュリ負圧は低いのでダ
イヤフラム56は第二負圧室59ノ方へ大きく移動して
主ノズル48の有効面積を小さくする。絞り弁4が大き
く開くとベンチュリ負圧と絞り弁4の側方の吸気負圧と
の差が小さくなり、成る開度以上ではベンチュリ負圧の
方が高くなるのでダイヤフラム56は第一負圧室58の
方へ次第に大きく移動して主ノズル48の有効面積を大
きくする。このようなダイヤフラム56の動きによって
、吸入空気量と燃料流量とを基本的に比例させ空燃比を
一定とすることができる。
The metering needle 79 controls the venturi negative pressure introduced into the first negative pressure chamber 58 through the first negative pressure path 60 and the throttle introduced into the second negative pressure chamber 59 through the second negative pressure path 62 in the normal operating state of the engine. The diaphragm 5 is determined by the intake negative pressure on the side of the valve 4 and the loads of the pressure spring 63 and balance spring 64.
The main nozzle 48 reciprocates in a straight line depending on the position of the main nozzle 48, and changes the effective area of the main nozzle 48 to change the fuel flow rate supplied to the engine. That is, when the throttle valve 4 is at the idle position or at a small opening, a high negative pressure is generated in the boat 62a of the second negative pressure path 62 that opens into the intake path 2, and since the venturi negative pressure is low, the diaphragm 56 moves largely toward the second negative pressure chamber 59, reducing the effective area of the main nozzle 48. When the throttle valve 4 opens wide, the difference between the venturi negative pressure and the intake negative pressure on the sides of the throttle valve 4 becomes small, and when the opening is greater than the opening, the venturi negative pressure becomes higher, so the diaphragm 56 closes in the first negative pressure chamber. 58 to increase the effective area of the main nozzle 48. By such movement of the diaphragm 56, the intake air amount and the fuel flow rate can be made basically proportional, and the air-fuel ratio can be kept constant.

本発明の装置が製造されたとき、燃料圧力調整器25、
主ノズル48、燃料流量調整器55、計量ニードル79
の寸法誤差、組立ての狂いによって主ノズル48からエ
ンジンに供給される燃料流量がエンジン要求流量と異な
る場合がある。このような場合、調整ねじ72を回して
針片73を前後へ動かし、第一分岐路71の有効面積を
変えて第二負圧室62に導入される空気量を変え、第二
負圧室69の負圧を規準値よりも高く或いは低くするこ
とによってダイヤフラム56の動きを修正し、燃料流量
をエンジン要求流量と一致させる。
When the device of the invention is manufactured, the fuel pressure regulator 25;
Main nozzle 48, fuel flow regulator 55, metering needle 79
The fuel flow rate supplied to the engine from the main nozzle 48 may differ from the engine required flow rate due to dimensional errors or assembly errors. In such a case, turn the adjustment screw 72 to move the needle piece 73 back and forth to change the effective area of the first branch path 71 and change the amount of air introduced into the second negative pressure chamber 62. By making the negative pressure at 69 higher or lower than the standard value, the movement of diaphragm 56 is modified to match the fuel flow rate with the engine required flow rate.

また、ダイヤフラム56が絞り弁4のアイドル位置のと
きの高い負圧で第二負圧室59の方へ大きく移動したと
き、計量ニードル79が主ノズル48に必要異常に深く
差込まれて燃料流量をエンジン要求流量よりも減少させ
ることがある。或いは絞り弁4が開いた位置から急激に
閉じて第二負圧室59の負圧が急激に高くなってダイヤ
フラム56がオーバストロークし計量ニードル79を主
ノズル48に衝突させて破損するという心配がある。そ
のために、ねじ97を回してストッパ98を前後に移動
させ、アイドル時に適正流量の燃料を供給する位置、或
いは主ノズル48に衝突する少し手前の位置で計量ニー
ドル79の先端がストッパ98に衝ってそれ以上は差込
まれないように調整する。
Also, when the diaphragm 56 moves largely toward the second negative pressure chamber 59 due to the high negative pressure when the throttle valve 4 is in the idle position, the metering needle 79 is inserted abnormally deep into the main nozzle 48, causing the fuel flow rate. may be lower than the engine's required flow rate. Alternatively, there is a fear that the throttle valve 4 may suddenly close from the open position and the negative pressure in the second negative pressure chamber 59 will suddenly increase, causing the diaphragm 56 to overstroke and cause the metering needle 79 to collide with the main nozzle 48, causing damage. be. To do this, turn the screw 97 to move the stopper 98 back and forth, so that the tip of the metering needle 79 hits the stopper 98 at a position where a proper flow of fuel is supplied at idle, or at a position slightly before hitting the main nozzle 48. Adjust so that no more can be inserted.

次に、エンジンが始動するときの動作を説明する。Next, the operation when the engine starts will be explained.

小形車両、産業機械、発電機などを駆動する比較的小排
気量のエンジンはガバナをもっており、吸入空気量を制
御する絞り弁はエンジンが停止しているとき半開または
全開とされている。
Relatively small displacement engines that drive small vehicles, industrial machinery, generators, etc. have governors, and the throttle valves that control the amount of intake air are half open or fully open when the engine is stopped.

エンジンは絞り弁を開いたまま始動し急激に高速回転す
るようになるが、成る回転速度に達するとガバナが働い
て絞り弁をアイドル位置まで閉じさせ、その後は運転者
の操作によって絞り弁を所要開度とするものである。
The engine starts with the throttle valve open and rapidly rotates at high speed, but when the engine reaches this speed, the governor works to close the throttle valve to the idle position, and then the driver operates the throttle valve as required. This is the opening degree.

このため、エンジンがクランキングを行なっているとき
ベンチュリ負圧、絞り弁4の側方の吸気負圧、絞り弁4
の下流側の吸気負圧はいずれも低い、従って、負圧通路
96によって絞り弁4の下流側と接続されている負圧室
93に導入される負圧は低く、始動ばね94がダイヤフ
ラム92を大気室90の方へ移動させてロッド89を押
し、弁体84を第一の弁座82に押付けて第一負圧路6
0を閉じ補助負圧路61を開いている。
For this reason, when the engine is cranking, the venturi negative pressure, the intake negative pressure on the side of the throttle valve 4, the throttle valve 4
The intake negative pressure on the downstream side of the throttle valve 4 is low. Therefore, the negative pressure introduced into the negative pressure chamber 93 connected to the downstream side of the throttle valve 4 by the negative pressure passage 96 is low, and the starting spring 94 causes the diaphragm 92 to Move it toward the atmospheric chamber 90 and push the rod 89, press the valve body 84 against the first valve seat 82, and open the first negative pressure path 6.
0 is closed and the auxiliary negative pressure path 61 is opened.

エンジンのクランクケースに発生するパルス圧の平均値
は2サイクルエンジンおよび4サイクルエンジンのいず
れであってもマイナスであって、補助負圧路61から弁
室81.出口路86を経て第一負圧室58に負圧が導入
される。このため、ダイヤフラム56は第一負圧室58
の方へ少し移動して主ノズル48から供給される始動用
燃料を増加させることができる。エンジンが完爆すると
吸気負圧はクランキング時に比べて高くなるので負圧室
93に導入される負圧が高くなってダイヤフラム92を
負圧室93の方へ移動させロッド89から離れる。この
ため、弁体84は戻しばね85のばね力で第一の弁座8
2から離れ第二の弁座83(:押付けられ、第一負圧路
60を第一負圧室58に連通させる。
The average value of the pulse pressure generated in the engine crankcase is negative regardless of whether it is a 2-cycle engine or a 4-cycle engine, and is negative from the auxiliary negative pressure path 61 to the valve chamber 81. Negative pressure is introduced into the first negative pressure chamber 58 via the outlet passage 86 . Therefore, the diaphragm 56 is connected to the first negative pressure chamber 58.
The starting fuel supplied from the main nozzle 48 can be increased by moving a little towards the main nozzle 48. When the engine completely explodes, the intake negative pressure becomes higher than during cranking, so the negative pressure introduced into the negative pressure chamber 93 becomes higher, causing the diaphragm 92 to move toward the negative pressure chamber 93 and away from the rod 89. Therefore, the valve body 84 is moved to the first valve seat 8 by the spring force of the return spring 85.
2, the second valve seat 83 (: is pressed, and communicates the first negative pressure path 60 with the first negative pressure chamber 58.

このように、エンジンの始動時に燃料流量を増加させる
ことは低い温度のときに有効であり。
Thus, increasing the fuel flow rate when starting the engine is effective at low temperatures.

そのために補助負圧路61に温度弁100が設けられて
いる。この温度弁100は片持ち式の板状のバイメタル
101の自由端に取付けた針状の弁体102を有してお
り、温度が低いとき弁孔+03を大きく開き温度が高い
とき閉じる。従って、温度が高いときにエンジンが始動
すると、第一負圧路60は負圧制御弁80によって閉鎖
され補助負圧路61は温度弁100によって閉鎖されて
いるため第一負圧室58は大気圧となっている。このた
め。
For this purpose, a temperature valve 100 is provided in the auxiliary negative pressure path 61. This temperature valve 100 has a needle-shaped valve body 102 attached to the free end of a cantilevered plate-shaped bimetal 101, and opens the valve hole +03 wide when the temperature is low and closes it when the temperature is high. Therefore, when the engine starts when the temperature is high, the first negative pressure chamber 58 becomes large because the first negative pressure path 60 is closed by the negative pressure control valve 80 and the auxiliary negative pressure path 61 is closed by the temperature valve 100. It is atmospheric pressure. For this reason.

ダイヤフラム56は第二負圧室59の方へ移動して主ノ
ズル48から供給される燃料流量をエンジンが完爆する
まで少量とする。
The diaphragm 56 moves toward the second negative pressure chamber 59 to reduce the amount of fuel supplied from the main nozzle 48 until the engine completely explodes.

更に、エンジンのクランクケースに発生させるパルス圧
を第一負圧室58に導入するとき、パルス圧の平均値が
低いとダイヤフラム56を充分に吸引して燃料を増加さ
せることができない。
Furthermore, when the pulse pressure generated in the engine crankcase is introduced into the first negative pressure chamber 58, if the average value of the pulse pressure is low, the diaphragm 56 cannot be sufficiently suctioned to increase the amount of fuel.

そのために補助負圧路61に一方向弁105が設けられ
ている。この一方向弁105は第9図を参照して球状の
弁体106とばね107とを有しており、燃料ポンプ5
のパルス室11から送られてくるパルス圧の一定以上の
負圧成分が弁体106に作用したときばね107を圧縮
して弁孔lO8を開く、従って、エンジンのクランキン
グ時に第一負圧室58を高い負圧とすることができる。
For this purpose, a one-way valve 105 is provided in the auxiliary negative pressure path 61. This one-way valve 105 has a spherical valve body 106 and a spring 107, as shown in FIG.
When the negative pressure component of the pulse pressure sent from the pulse chamber 11 acts on the valve body 106, it compresses the spring 107 and opens the valve hole lO8. Therefore, when the engine is cranked, the first negative pressure chamber 58 can be at a high negative pressure.

エンジンが完爆した後は、先に述べたように絞り弁4が
大きく開かれているので急激に回転速度が高くなり、次
にガバナが働いて絞り弁4をアイドル位置まで閉じさせ
る。このとき、第二負圧路62の吸気路2へ開口したボ
ート62aは絞り弁4の上流側から下流側に突然移行し
て第二負圧室59の圧力が急激に変化するのを防ぐため
、ボート62aは吸気路2の軸線方向へ向かって複数個
設けられている。また、ベンチュリ負圧は絞り弁4が閉
じるに従って低くなるので。
After the engine has completely exploded, the throttle valve 4 is wide open as described above, so the rotational speed increases rapidly, and then the governor operates to close the throttle valve 4 to the idle position. At this time, in order to prevent the boat 62a opened to the intake path 2 of the second negative pressure path 62 from suddenly shifting from the upstream side to the downstream side of the throttle valve 4 and the pressure in the second negative pressure chamber 59 to change suddenly. , a plurality of boats 62a are provided in the axial direction of the intake passage 2. Also, the venturi negative pressure decreases as the throttle valve 4 closes.

第一負圧室58の圧力が急激に変化する心配がある。そ
こで、第一補正通路65の吸気路2へ開口したボート6
5aを吸気路2の軸線方向へ向かって複数個設けた。こ
れらのボート62a、65aの配列によって絞り弁4が
アイドル位置の近くで動いたときの第一負圧室58と第
二負圧室59の圧力の急激な変化を避けることができ、
ダイヤフラム56の動きを安定化して燃料流量を急激に
変化させたり計量ニードル79をオーバストロークさせ
て燃料流量を大幅に狂わせたりしない。
There is a concern that the pressure in the first negative pressure chamber 58 may change rapidly. Therefore, the boat 6 which opens the first correction passage 65 to the intake passage 2
A plurality of the air intake passages 5a are provided in the axial direction of the intake passage 2. By arranging these boats 62a and 65a, it is possible to avoid sudden changes in the pressures of the first negative pressure chamber 58 and the second negative pressure chamber 59 when the throttle valve 4 moves near the idle position.
The movement of the diaphragm 56 is stabilized to prevent sudden changes in the fuel flow rate or overstroke of the metering needle 79 to prevent the fuel flow rate from being significantly deviated.

第二負圧路62は特開平1−32031号公報に開示さ
れているように絞り弁4の下流側で吸気路2に開口させ
ることも可能である。この場合は、第二負圧室59の圧
力の急激な変化を避けるため、絞り69および補正通路
70の針片73が有効に働く。
The second negative pressure path 62 can also be opened into the intake path 2 on the downstream side of the throttle valve 4, as disclosed in Japanese Patent Application Laid-Open No. 1-32031. In this case, the throttle 69 and the needle piece 73 of the correction passage 70 work effectively to avoid a sudden change in the pressure in the second negative pressure chamber 59.

第4図に見られるように、第二負圧室59の最も低い位
置に第二負圧路62を接続し、高い位置に補正通路70
を接続すると、計量ニードル79を伝わって第二負圧室
59に入った燃料が空気と一緒に第二負圧路62を通っ
て吸気路2に排出され、第二負圧室59にためられるこ
とがない、補正通路70の第一分岐路71の有効面積を
調整する針片73は、第二負圧室59に導入される空気
流量を制御して第二負圧室59の負圧を調整し、ダイヤ
フラム56の位置従って主ノズル48から供給される燃
料流量を適正とするように働<、第二分岐路74の温度
弁75は温度が低いときに弁孔78を大きく開いて第二
負圧室59に大量の空気を導入し、第二負圧室59の負
圧を低下させてダイヤフラム56を通常よりも第一負圧
室58の方へ移動させ、燃料流量を増加するように働く
As seen in FIG. 4, the second negative pressure passage 62 is connected to the lowest position of the second negative pressure chamber 59, and the correction passage 70 is connected to the highest position.
When connected, the fuel that has passed through the metering needle 79 and entered the second negative pressure chamber 59 is discharged together with air through the second negative pressure path 62 to the intake path 2, and is stored in the second negative pressure chamber 59. The needle piece 73 that adjusts the effective area of the first branch path 71 of the correction passage 70 controls the flow rate of air introduced into the second negative pressure chamber 59 to increase the negative pressure in the second negative pressure chamber 59. The temperature valve 75 of the second branch passage 74 opens the valve hole 78 wide when the temperature is low and operates to adjust the position of the diaphragm 56 and thus the fuel flow rate supplied from the main nozzle 48. A large amount of air is introduced into the negative pressure chamber 59, the negative pressure in the second negative pressure chamber 59 is lowered, and the diaphragm 56 is moved more toward the first negative pressure chamber 58 than usual, thereby increasing the fuel flow rate. work.

本発明の要旨は第5図に示されているような低温増量機
構52を燃料圧力調整器25に付設したことにある。
The gist of the present invention is that a low temperature increase mechanism 52 as shown in FIG. 5 is attached to the fuel pressure regulator 25.

即ち、バイメタル44は温度が低いときバイメタルロッ
ド46を押してダイヤフラム37を調圧室36の方へ移
動させ、圧力調整弁26を大きく開がせて燃料ポンプ5
から送られてくる燃料を大量に調圧室36に導入し、燃
料圧力を高くするように(至)く、温度が高いときバイ
メタルロッド46はダイヤフラム37から離れてダイヤ
フラム37を正常な位置に戻して燃料を予め設定した範
囲内の一定正圧力に調整させる。
That is, when the temperature is low, the bimetal 44 pushes the bimetal rod 46 to move the diaphragm 37 toward the pressure regulating chamber 36, widening the pressure regulating valve 26, and shutting down the fuel pump 5.
In order to increase the fuel pressure by introducing a large amount of fuel sent from to adjust the fuel to a constant positive pressure within a preset range.

その結果、温度が低いときに主ノズル48がらエンジン
に供給される燃料が増量され、またバイメタル44を用
いたことによってバイメタルロッド46は温度に応じて
位置を変え、燃料を温度に応じた適正量に増量すること
ができる。従って、負圧制御弁80を廃して第一負圧室
58に常時第一負圧路60を接続した構成としても実用
上差支えはない。
As a result, when the temperature is low, the amount of fuel supplied to the engine from the main nozzle 48 is increased, and by using the bimetal 44, the bimetal rod 46 changes its position according to the temperature, and the fuel is supplied in the appropriate amount according to the temperature. The amount can be increased to Therefore, there is no practical problem even if the negative pressure control valve 80 is eliminated and the first negative pressure path 60 is always connected to the first negative pressure chamber 58.

尚、バイメタル44の代りに例えばサーモワックスを用
いても同じ結果が得られるが、バイメタルは価格および
構造の面で有利である。
Note that the same result can be obtained by using, for example, thermowax instead of the bimetal 44, but bimetal is advantageous in terms of cost and structure.

[発明の効果コ 本発明によると、温度が低いときに圧力調整弁を大きく
開かせて調圧室に燃料を大量に導入し、エンジンに供給
される燃料を増量して低温始動性、暖機運転性を向上さ
せることができる。
[Effects of the Invention] According to the present invention, when the temperature is low, the pressure regulating valve is opened wide to introduce a large amount of fuel into the pressure regulating chamber, thereby increasing the amount of fuel supplied to the engine and improving low-temperature startability and warm-up. Drivability can be improved.

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

第1図は本発明の一実施例を示す平面図、第2図は一部
切載した正面図、第3図は第1図のA −A線に沿う拡
大断面図、第4図は第1図のB−B線に沿う拡大断面図
、第5図は第2図のC−C線に沿う拡大断面図、第6図
は第2図のD−D線に沿う拡大断面図、第7図は第2図
のE−E線に沿う拡大断面部分図、第8図は第1図のF
−Filに沿う拡大断面部分図、第9図は第1図のG−
G線に沿う拡大断面部分図、第10図は全体の部品と通
路との関係を説明する図である。 2・・・吸気路、3・・・固定ベンチュリ、4・・・絞
り弁、5・・・燃料ポンプ、25・・・燃料圧力調整器
、47・・・燃料通路、48・・・主ノズル、26・・
・圧力調整弁、36・・・調圧室、37・・・ダイヤフ
ラム、39・・・大気室、40・・・調圧ばね、44・
・・バイメタル、46・・・バイメタルロッド、52・
・・低温増量機構、55・・・燃料流量調整器、79・
・・計量ニードル、
FIG. 1 is a plan view showing one embodiment of the present invention, FIG. 2 is a partially cutaway front view, FIG. 3 is an enlarged sectional view taken along line A-A in FIG. 1, and FIG. 1. FIG. 5 is an enlarged sectional view taken along line C-C in FIG. 2. FIG. 6 is an enlarged sectional view taken along line D-D in FIG. 2. Figure 7 is an enlarged partial cross-sectional view taken along line E-E in Figure 2, and Figure 8 is F in Figure 1.
- An enlarged partial cross-sectional view along Fil, Fig. 9 is G- of Fig. 1.
FIG. 10, an enlarged partial cross-sectional view taken along line G, is a diagram illustrating the relationship between the overall components and the passages. 2... Intake path, 3... Fixed venturi, 4... Throttle valve, 5... Fuel pump, 25... Fuel pressure regulator, 47... Fuel passage, 48... Main nozzle , 26...
・Pressure regulating valve, 36...Pressure regulating chamber, 37...Diaphragm, 39...Atmospheric chamber, 40...Pressure regulating spring, 44...
... Bimetal, 46... Bimetal rod, 52.
・・Low temperature increase mechanism, 55・・Fuel flow rate regulator, 79・
・Measuring needle,

Claims (1)

【特許請求の範囲】 固定ベンチュリおよび絞り弁を有する吸気路と、前記吸
気路に開口し計量ニードルにより有効面積が可変の主ノ
ズルと、燃料をほぼ一定の正圧力に調整して前記主ノズ
ルに送る燃料圧力調整器と、ベンチュリ負圧と絞り弁の
側方またはその下流側の吸気負圧との差圧力に応じて前
記計量ニードルを動作させエンジン吸気量にほぼ対応し
て前記主ノズルの有効面積を変化させる燃料流量調整器
とを具えており、前記燃料圧力調整器は燃料をほぼ一定
の正圧力に維持させる調圧室と、大気室と、前記二つの
室を仕切ったダイヤフラムと、前記大気室に装入されて
前記ダイヤフラムを前記調圧室の方へ押す調圧ばねと、
前記調圧室に接続された燃料導入路を前記ダイヤフラム
の位置に応じて開閉する圧力調整弁とから構成されてい
るエンジンの燃料供給装置において; 温度が高いとき前記ダイヤフラムを正常な位置で動作さ
せるが、温度が低いとき前記ダイヤフラムを前記調圧室
の方へ移動させ前記圧力調整弁を大きく開いて調圧室の
燃料圧力を高くするように働く低温増量機構を具えてい
ることを特徴とする燃料供給装置。
[Scope of Claims] An intake passage having a fixed venturi and a throttle valve, a main nozzle which opens into the intake passage and whose effective area is variable by means of a metering needle, and a fuel which is adjusted to a substantially constant positive pressure and supplied to the main nozzle. The fuel pressure regulator operates the metering needle in accordance with the differential pressure between the venturi negative pressure and the intake negative pressure on the side of the throttle valve or downstream thereof, and adjusts the effectiveness of the main nozzle approximately in accordance with the engine intake amount. a fuel flow rate regulator that changes the area; the fuel pressure regulator includes a pressure regulation chamber that maintains the fuel at a substantially constant positive pressure; an atmospheric chamber; a diaphragm that partitions the two chambers; a pressure regulating spring inserted into an atmospheric chamber and pushing the diaphragm toward the pressure regulating chamber;
In an engine fuel supply system comprising a pressure regulating valve that opens and closes a fuel introduction path connected to the pressure regulating chamber according to the position of the diaphragm; the diaphragm is operated at a normal position when the temperature is high. is characterized by comprising a low-temperature increase mechanism that moves the diaphragm toward the pressure regulating chamber to widen the pressure regulating valve to increase the fuel pressure in the pressure regulating chamber when the temperature is low. Fuel supply device.
JP1282580A 1989-10-30 1989-10-30 Engine fuel supply Expired - Fee Related JP2791432B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP1282580A JP2791432B2 (en) 1989-10-30 1989-10-30 Engine fuel supply

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP1282580A JP2791432B2 (en) 1989-10-30 1989-10-30 Engine fuel supply

Publications (2)

Publication Number Publication Date
JPH03145566A true JPH03145566A (en) 1991-06-20
JP2791432B2 JP2791432B2 (en) 1998-08-27

Family

ID=17654346

Family Applications (1)

Application Number Title Priority Date Filing Date
JP1282580A Expired - Fee Related JP2791432B2 (en) 1989-10-30 1989-10-30 Engine fuel supply

Country Status (1)

Country Link
JP (1) JP2791432B2 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100827984B1 (en) * 2007-04-03 2008-05-07 (주)모토닉 Apparatus for raise the pressure of gas fuel vehicle

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100827984B1 (en) * 2007-04-03 2008-05-07 (주)모토닉 Apparatus for raise the pressure of gas fuel vehicle

Also Published As

Publication number Publication date
JP2791432B2 (en) 1998-08-27

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