GB2108204A - Carburetor with a sonic idling system for an IC engine - Google Patents
Carburetor with a sonic idling system for an IC engine Download PDFInfo
- Publication number
- GB2108204A GB2108204A GB08230840A GB8230840A GB2108204A GB 2108204 A GB2108204 A GB 2108204A GB 08230840 A GB08230840 A GB 08230840A GB 8230840 A GB8230840 A GB 8230840A GB 2108204 A GB2108204 A GB 2108204A
- Authority
- GB
- United Kingdom
- Prior art keywords
- fuel
- slow
- intake passage
- air intake
- air
- 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.)
- Withdrawn
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
- F02M3/00—Idling devices for carburettors
- F02M3/08—Other details of idling devices
- F02M3/12—Passageway systems
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
- F02M7/00—Carburettors with means for influencing, e.g. enriching or keeping constant, fuel/air ratio of charge under varying conditions
- F02M7/12—Other installations, with moving parts, for influencing fuel/air ratio, e.g. having valves
- F02M7/14—Other installations, with moving parts, for influencing fuel/air ratio, e.g. having valves with means for controlling cross-sectional area of fuel spray nozzle
- F02M7/16—Other installations, with moving parts, for influencing fuel/air ratio, e.g. having valves with means for controlling cross-sectional area of fuel spray nozzle operated automatically, e.g. dependent on exhaust-gas analysis
- F02M7/17—Other installations, with moving parts, for influencing fuel/air ratio, e.g. having valves with means for controlling cross-sectional area of fuel spray nozzle operated automatically, e.g. dependent on exhaust-gas analysis by a pneumatically adjustable piston-like element, e.g. constant depression carburettors
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Control Of The Air-Fuel Ratio Of Carburetors (AREA)
Abstract
An idling air intake passage 21 and/or an idling fuel passage 25 is provided with a fixed or adjustable restriction 22, 28. At or adjacent an air-fuel mixture outlet 21b of the idling air passage 21 there is provided a converging-diverging nozzle 23 which permits a flow rate of the air-fuel mixture at the throat portion 24 thereof to be at sonic velocity irrespective of variations in intake manifold vacuum during low speed engine operation. With this arrangement, the air-fuel ratio may be maintained at a constant value and accordingly, idling operation may be stabilized and pollutant exhaust gas emission may be reduced. <IMAGE>
Description
SPECIFICATION
Carburetor for an internal combustion engine
This invention relates to a carburetor for an internal combustion engine having a slow fuel system, and more particularly to a carburetor which may supply an air-fuel mixture to an intake manifold with the air-fuel ratio maintained at a constant value irrespective of any variations in intake manifold vacuum during low speed engine operation.
It is well known to provide a carburetor with a slow fuel system including an air intake passage which bypasses a throttle valve and in which fuel is injected with high velocity air flow from an idle port in the port in the slow fuel system. For example, the idle port is provided with a restriction means such as a venturi whereby the air velocity at the throat portion thereof becomes substantially sonic and a fuel discharging port is opened into the restriction means, thereby permitting fuel to be sucked by the negative pressure created in the restriction means and to be atomized by the air flow. The atomized air-fuel mixture is injected into an air intake passage. According to such a known arrangement, a sufficient pressure differential at the fuel discharge port may be obtained and mass air flow rate may be maintained at constant value.However, pressure at the fuel discharging port varies with fluctuations in intake manifold vacuum and accordingly, fuel flow rate also varies, with the result that air-fuel ratio may not be maintained at a constant value. In another known carburetor having a slow fuel system air and fuel are mixed in a slow air intake passage and thereafter, the air-fuel mixture is injected from an idle port at sonic velocity. In general, the pressure ratio P1/P2 (P,: pressure at the downstream portion of an idle port, i.e.
intake manifold vacuum; P2: pressure at the upstream portion of an idle port, i.e., pressure in the slow air intake passage) should be approximately equal to or less than 0.5 in order to render a flow rate of air-fuel mixture at the idle port to reach sonic velocity. However, in such a known carburetor, when the engine load becomes heavy and the throttle valve opening is increased so that the intake manifold vacuum becomes more than a value of about - 360 mmHg, the pressure ratio P./P2 becomes more than 0.5 and the flow rate of air-fuel mixture is reduced to a value less than the sonic velocity. As a result, there are variations in the mass air/fuel mixture flow rate and the air-fuel ratio.In a variable venturi type carburetor which generally does not have a slow fuel system, part of fuel which is discharged from the main jet during low speed engine operation and which sticks to an end surface of a suction piston or fuel may not be stably discharged because of a surrounding compiicated air stream. For the above reasons, a constant air-fuel ratio and stable idle operation may not be established.
It has been desired to solve this problem by providing a slow fuel system in a carburetor which ensures a constant fuel supply at all times and a constant air-fuel ratio.
Accordingly, a primary object of the present invention is to provide a carburetor having a slow fuel system which supplies an air-fuel mixture to the intake manifold at sonic velocity irrespective of variations in intake manifold vacuum during low speed engine operation.
Another object of the present invention is to provide a carburetor having a slow fuel system which ensures a constant air-fuel ratio irrespective of variations in intake manifold vacuum during low speed engine operation.
A further object of the present invention is to provide a carburetor having a slow fuel system which may stabilize an idle operation and reduce pollutant exhaust gas and furthermore, improve fuel consumption.
According to the present invention, at least one for each of a slow air intake passage and a slow fuel passage is provided with restriction means. At an air-fuel mixture outlet of the slow air intake passage or adjacent to the outlet, there is provided a convergingdiverging nozzle which permits a flow rate of the air-fuel mixture at the throat portion thereof to be at sonic velocity irrespective of variations in intake manifold vacuum during low speed engine operation. With this arrangement, an air-fuel ratio may be maintained at a constant value irrespective of variations in intake manifold vacuum during low speed engine operation, whereby idle operation maybe stabilized and pollutant exhaust gas may be reduced.
In order that the invention may be more readily understood, reference will now be made to the accompanying drawings, in which: Figure 1 is a vertical sectional view of a variable venturi carburetor according to a first preferred embodiment of the present invention;
Figure 2 shows the relationship between air-fuel ratio and intake manifold vacuum according to the present invention in comparison with prior art;
Figure 3 is a vertical sectional view of a variable venturi carburetor according to a second preferred embodiment;
Figures 4 and 5 are vertical sectional views of the essential parts of variable venturi carburetors according to third and fourth preferred embodiments, respectively; and
Figure 6 is a vertical sectional view of a fixed venturi carburetor according to a fifth preferred embodiment.
Referring now to Fig. 1, there is shown a carburetor body 1 of a variable venturi type having a float chamber 2, a first air intake passage 3, a throttle valve 4 and a venturi portion 5. Reference numeral 6 designates a main fuel passage communicating with the float chamber 2 and the venturi portion 5.
The main fuel passage 6 is provided with a
main fuel jet 9. The venturi portion 5 is defined upstream of the throttle valve 4 by the inside wall 10 of the first air intake passage 3 and by the right-hand (as illustrated) end portion 1 2 of a suction piston 11.
A suction chamber 1 3 is defined by a cylindrical portion 1 a of the carburetor body 1 and by the suction piston 11 which is slidably inserted into the cylindrical portion 1a. A compression spring 1 5 is inserted in the suction chamber 1 3 and serves normally to urge the suction piston 11 toward the inside wall
10 of the first air intake passage 3. A vacuum communication port 1 6 is provided at the right-hand end portion 1 2 of the suction piston 11 and is adapted to communicate with the suction chamber 1 3 and the venturi portion 5. An atmospheric pressure chamber 1 7 is defined by the sliding flange portion 11 a of the suction piston 11 and by the carburetor body 1.The chamber 1 7 is provided with an atmospheric pressure communication port 1 8 in the vicinity of the inlet of the air intake passage 3, whereby ambient air is induced through the port 1 8. A fuel metering needle 1 9 is fixed to the right-hand end portion 1 2 of the suction piston 11 at its central portion.
The free end of the metering needle 1 9 is laterally reciprocably inserted in the interior of the main fuel jet 9.
Reference numeral 21 designates a second air intake passage. An air inlet 21 a of the second air intake passage 21 opens into the first air intake passage 3 on the upstream side of the venturi portion 5 and an air/fuel outlet 21b opens into the first air intake passage 3 on the downstream side of the throttle valve 4. The second air intake passage 21 is provided with a fixed venturi 22 on the way thereof and is provided with a nozzle 23 adjacent to the air/fuel outlet 21 b. The nozzle 23 is designed in such a manner that an amount of air passing through its throat portion 24 becomes smaller than an amount of induced air during idle operation. A fuel discharging port 26 in communication with a slow fuel passage 25 opens into the most restricted portion of the fixed venturi 22.The slow passage 25 communicates with the float chamber 2 via a slow jet 27 provided on the way thereof and opens into the upstream portion of the second air intake passage 21 through an air restriction 28 diposed opposite the slow jet 27.
In operation, during middle and high speed engine operation, the suction piston 11 laterally reciprocates in response to an amount of air induced by engine vacuum and accordingly, fuel stored in the float chamber 2 is
supplied through the main fuel passage 6 to
the main fuel jet 9 and is metered by the
metering needle 1 9 and the main fuel jet 9,
and then is discharged into the venturi portion
5, wherein the amount of fuel to be dis
charged is proportional to the amount of air
passing through the venturi portion 5. During
low speed engine operation, the throttle valve
4 is in its nearly closed position, so that air is
dominantly induced through the air inlet 21a
into the second air intake passage 21 and
negative pressure is created at the most re
stricted portion of the fixed venturi 22.Be
cause of this negative pressure, the fuel
stored in the float chamber 2 is sucked up
through the slow fuel passage 25 to the slow
jet 27. For a while, part of the induced air is
metered by the air restriction 28 to enter the
slow fuel passage 25. Thus, such metered air
is mixed with the fuel metered by the slow jet
27 and the air-fuel mixture, which is under
emulsified state, flows through the down
stream portion cf the slow fuel passage 25 to
be discharged from the fuel discharging port
26.Such discharged air-fuel mixture is intro
duced to the nozzle 23 and flow velocity of
the mixture is accelerated by the pressure
differential existing between the upstream and
the downstream portions of the nozzle 23,
thereby injecting the accelerated air-fuel mix
ture from the outlet 21 b into the downstream
portion of the throttle valve 4 and then intro
ducing such injected fuel to an intake mani
fold (not shown).
It is generally known in the art that when
the ratio of the pressure at the most restricted
portion of the nozzle to the pressure at the
entry thereof reaches the value of 0.528, the
gas velocity reaches a constant sonic velocity
at the most restricted portion and the mass
gas flow rate at the nozzle becomes constant.
Accordingly when a converging nozzle is em -ployed, the ratio of the pressure at its most
restricted portion or at its exit to the pressure
at the entry needs to be increased. If such a
converging nozzle is used for the nozzle 23 in
the first preferred embodiment, sonic velocity
may be achieved, provided that ratio of the
exit pressure or the intake manifold vacuum to
the entry pressure is equal to or less than the
value of 0.528. As a result, the range of the
intake manifold vacuum is considerably limsited. Consequently, in the first preferred em
bodiment, the nozzle 23 is a convergingdiverging nozzle which converges from its
entry to its throat portion and diverges from
its throat portion to its exit. In this type of
converging-diverging nozzle 23, PO/Pj (Pj: en
try pressure; PO: exit pressure or intake mani -fold vacuum) ranges from 0 to 0.8 and PO/P.
(P,: pressure at the throat portion) is equal to
or less than 0.528. Thus, the velocity at the throat portion 24 becomes sonic and the
mass air flow rate at the nozzle 23 becomes constant. If Pi is atmospheric pressure, P0 ranges from - 760 mmHg to - 1 52 mmHg.
However, in the first preferred embodiment, as the air-fuel mixture flows through the nozzle 23, P0 practically ranges from - 760 mmHg to - 200 mmHg, which may be a sufficient value to cover the low speed area of operation. Accordingly, the mass air flow rate at the nozzle 23 is at all times constant irrespective of variations in the intake manifold vacuum, and as a result, the negative pressure downstream of the fixed venturi 22 becomes constant. Consequently, the fuel flow rate at the fixed venturi 22 is also constant irrespective of variations in the intake manifold vacuum.
Referring next to Fig. 2, the air-fuel ratio is all times constant irrespective of variations in intake manifold vacuum at an engine speed of 800 rpm as shown by the solid lines. On the other hand, in a conventional carburetor, the air-fuel ratio varies with intake manifold vacuum as shown by the dashed line.
As should be apparent from the above description, the carburetor of this embodiment ensures a constant air-fuel ratio and a stable fuel supply. As a result, idle operation may be stabilized and pollutant exhaust gas may be reduced, and furthermore fuel consumption may be improved.
In some embodiments which will be hereinafter described, the same reference numerals are used to designate the same parts or elements.
Referring next to Fig. 3, which illustrates a variable venturi carburetor of the second preferred embodiment, there is provided a variable restriction means at the air inlet of the second air intake passage 21. The variable restriction means comprises a seat 30 and a tapered needle 31 threaded through the carburetor body 1 and adapted to be reciprocably inserted into the seat 30. The needle 31 is biased by a compression spring 32 toward its head portion and thus, the degree of opening of the seat 30 may be adjusted by changing the extent of insertion of the needle 31. The slow fuel passage 25 opens into the second air intake passage 21 directly downstream of the seat 30. A slow jet 33 is provided at the fuel outlet of the float chamber 2 communicating with the slow fuel passage 25. A nozzle 23 is provided at the airfuel outlet of the second air intake passage 21.The nozzle 23 is a converging-diverging type nozzle similar to that employed in the first preferred embodiment and a part of the nozzle 23 projects into the first air intake passage 3 downstream of the throttle valve 4.
The air velocity at the throat portion 24 of the nozzle 23 is sonic under a manifold vacuum of - 760 mmHg to - 200 mmHg.
In operation, air is introduced through the annular clearance defined between the needle 31 and the seat 30 into the second air intake passage 21, thereby creating a negative pressure at the opening of the slow fuel passage 25. On the other hand, fuel stored in the float chamber 2 is metered by the slow jet 33 and is introduced to its opening where the fuel is discharged and mixed with the air supplied through the seat 30, wherein even if the negative pressure at the opening of the slow fuel passage 25 at the opening of the slow fuel passage 25 is about 5 percent of the manifold vacuum of - 500 mmHg, fuel metering of the slow system may be ensured. The velocity of the air-fuel mixture at the throat portion 24 of the nozzle 23 becomes sonic and the mass fuel flow rate is maintained at a constant level.Under these conditions, the air-fuel mixture is injected from the nozzle 23 into the first air intake passage 5 and is then introduced to the intake manifold (not shown), thereby accomplishing satisfactory effectiveness similar to that in the previous preferred embodiment.
When the extent of insertion of the needle 31 into the seat 30 is varied, the velocity of air flowing into the second air intake passage 21 is varied with the air flow maintained at constant level because of constant mass airfuel mixture flow rate at the nozzle 23. As a result, the negative pressure at the opening of the slow fuel passage 25 into the second air intake passage 21 and the fuel flow rate is varied. As is apparent from the foregoing description, control of fuel flow rate or the airfuel ratio may be ensured by adjusting the extent of insertion of the needle 31 into the seat 30, and the air-fuel ratio may be set to a required value.
Referring next to Fig. 4 illustrating a part of a carburetor of a third preferred embodiment, there is provided an air restriction means 35 at an air inlet of the second air intake passage 21 which means serves to generate a negative pressure downstream of the means 35 required for metering fuel flow rate in the flow fuel system. A nozzle 23 similar to that in the embodiment of Fig. 3 is provided at the airfuel mixture outlet of the second air intake passage 21. Th slow fuel passage 25 opens into the second air intake passage 21 on the way thereof, and is provided with a variable fuel restriction means comprising a seat 36 and a tapered needle 37 reciprocably inserted into the seat 36. As is similar to the previous preferred embodiment, the needle 37 is threaded into a hole in the carburetor body 1 and is biased outwardly of the body 1 by a compression spring 38.With this arrangement, the extent of insertion of the needle 37 into the seat 36 may be controlled and accordingly, the degree of opening of the variable fuel restriction means.
In operation, when the air flowing in the first air intake passage 3 is introduced through the air restriction means 35 into the second air intake passage 21, the fuel stored in the float chamber 2 is sucked up by way of the second air intake passage 25 upstream of the variable fuel restriction means and the fuel flow rate is controlled by the variable fuel restriction means. The fuel dicharged from the variable fuel restriction means is mixed with the air flowing in the second air intake passage 21 and it then supplied to the nozzle 23.
At the throat portion 24 of the nozzle 23, the velocity of air-fuel mixture becomes sonic under the condition of constant mass air-fuel mixture flow rate. Thus, the air-fuel mixture is injected into the first air intake passage 3 downstream of the throttle valve 4 and is then induced into an intake manifold (not shown).
As is similar to the embodiment of Fig. 3, the fuel flow rate may be controlled by adjusting the extent of insertion of the needle 37 into the seat 36 and therefore the air-fuel ratio may be set to a required value.
Referring now to Fig. 5, which illustrates a part of a variable.venturi carburetor of the third preferred embodiment, there is provided an air restriction means 40 at an air inlet of the second air intake passage 21 which means 40 serves to generate a negative pressure downstream thereof required.for metering fuel flow rate in the slow fuel system. A nozzle 23 similar to that of Fig. 4 is provided at an air-fuel mixture outlet of the second air intake passage 21. The slow fuel passage 25 opens into the second air intake passage 21 directly downstream of the air restrictions means 40. A slow jet 41 is provided at the fuel outlet of the float chamber 2 communicating with the slow fuel passage 25.There is provided, at the opening of the slow fuel passage 25, a variable restriction means which comprises a seat 42 and a tapered needle 43 threaded through the carburetor body 1 and which is adapted to be reciprocably inserted into the seat 42. The needle 43 is biased by a compression spring 44 toward its head portion and thus, the degree of opening of the seat 42 may be adjusted by changing the extent of insertion of the needle 43 into the seat 42.
In operation, air is introduced through the air restriction means 40 into the second air intake passage 21, thereby creating a negative pressure at the opening of the slow fuel passage 25. On the other hand, fuel stored in the float chamber 2 is metered by the slow jet 41 and is introduced to is opening where the fuel is discharged and mixed with the air supplied through the seat 42. As the velocity of the air-fuel mixture at the throat portion 24 of the nozzle 23 becomes sonic and the mass flow rate is constant, the velocity of air introduced through the air restriction means 40 becomes constant.However, when the introduced air is supplied to the variable air-fuel mixture restriction means, the velocity of the air-fuel mixture increases with the degree of opening of the seat 42 and thereafer gradually decreases to the extent that it corresponds to the cross-sectional area of the second air
intake passsage 21. In this embodiment, the
slow fuel passage 25 opens into the second
air intake passage 21 directly upstream of the
seat 42 and accordingly, the negative pres
sure at the opening will be influenced by the
variable air-fuel mixture restriction means, i.e.,
the negative pressure at the opening of the
slow fuel passage 25 varies with the extent of
insertion of the needle 43 into the seat 42
and thus the fuel flow rate is varied.Accord
ingly, the air-fuel ratio may be controlled by
changing the extent of insertion of the needle
43 to set it to a required value as is similar to
the second and the third preferred embodi
ments.
Referring next to Fig. 6 illustrating a carbu
retor provided with a well-known fixed ven
turi, according to the fifth preferred embodi
ment, reference numeral 51 designates a car
buretor body of a fixed venturi type having a
float chamber 52, a first air intake passage
53, a throttle valve 54, a venturi portion 55
and a small venturi 56. Reference numeral 57
designates a main fuel passage communicat
ing with the float chamber 52 and the small
venturi 56. A main fuel jet 58 is provided
near the fuel outlet of the float chamber 52.
Reference numeral 59 designates a second
air intake passage which opens into the first
air intake passage 53 upstream of the small
venturi 56 and which also opens into the
passage 53 downstream of the throttle valve
54. A variable air restriction means, which
comprises a seat 60 and a tapered needle 61
threaded into a hole in the carburetor body
51 and is adapted to be reciprocably inserted
into the seat 60, is provided on the way of
the second air intake passage 59. The needle
61 is biased by a compression spring 62
toward its head portion and thus, the degree
of opening of the seat 60 may be controlled
by changing the extent of insertion of the
needle 61 into the seat 60. A slow fuel
passage 63 communicating with a main fuel
passage 57 through a slow jet 64 is provided
downstream of the variable air restriction
means. A nozzle 65 is provided at the air-fuel
mixture outlet of the second air intake pas
sage 59. The nozzle 65 is a converging
diverging type nozzle similar to that employed
in the embodiment of Fig. 5 and a part of the
nozzle 65 projects into the first air intake
passage 53 downstream of the throttle valve
54. The air velocity at the throat portion 66 of
the nozzle 65 is sonic under a manifold va
cuum of - 760 mmHg to - 200 mmHg.
During low speed engine operation, air is
induced through the second air intake passage
59 to the variable restriction means and a
negative pressure is created downstream of
the variable restriction means. Because of this
negative pressure, the fuel stored in the float
chamber 52 is sucked up through the slow 'fuel passage 63 after being metered by the slow jet 64 and is mixed with the air directly downstream of the needle 61. Such an airfuel mixture is supplied to the nozzle 65 where the velocity of the mixture becomes sonic and is injected into the first air intake passage 53 downstream of the throttle valve 54 As is similar to the embodiment of Fig. 3, when the extent of insertion of the needle 61 into the seat 60 is varied, the velocity of air flowing through the variable restriction means is varied under the condition of contant air flow rate. As a result, the negative pressure at the opening of the slow fuel passage 63 into the second air intake passage 59 is varied, and accordingly, fuel flow rate is also varied.
Consequently, control of fuel flow rate or airfuel ratio may be ensured by adjusting the extent of insertion of the needle 61 into the seat 60, and the air-fuel ratio may be set to the required value.
Having thus described the preferred embodiments of the invention is should be understood that numerous structural modifications and adaptations may be restored to without departing from the spirit of the invention.
Claims (11)
1. A carburetor for an internal combustion engine, having a main air intake passage, a throttle valve provided in said main air intake passage, a slow air intake passage bypassing said throttle valve, an air inlet provided at one end of said slow air intake passage and opening into said main air intake passage upstream of said throttle valve, an air-fuel mixture outlet provided at the other end of said slow air intake passage and opening into said main air intake passage downstream of said throttle valve, a float chamber, and a slow fuel passage communicating with said float chamber and said slow air intake passage, wherein restriction means is provided in at least one of said slow air intake passage and said slow fuel passage and a converging-diverging nozzle is provided at or adjacent said air-fuel mixture outlet of the slow air intake passage, said nozzle permitting a flow rate of air-fuel mixture at the throat portion of said converging-diverging nozzle to be at sonic valocity irrespective of variations in intake manifold vacuum.
2. The carburetor as defined in claim 1, wherein said restriction means provided in said slow air intake passage is fixed venturi and said slow fuel passage opens into a throat portion of said fixed venturi.
3. The carburetor as defined in claim 1, wherein said restriction means for the slow air intake passage is provided downstream of said air inlet and said slow fuel passage opens into said slow air intake passage on the downstream side of said restriction means for the slow air intake passage.
4. The carburetor as defined in claim 1, wherein said restriction means for the slow air intake passage is a variable restriction comprising a seat and a needle reciprocably inserted into said seat for adjusting the degree of opening of said seat.
5. The carburetor as defined in claim 1, wherein said restriction means for the slow fuel passge is a variable restriction comprising a seat and a needle reciprocably inserted into said seat for adjusting the degree of opening of said seat.
6. The carburetor as defined in claim 1, wherein said restriction means for the slow air intake passage comprises a fixed restriction provided at said inlet and a variable restriction provided downstream of said fixed restriction, said variable restriction comprising a seat and a needle reciprocably inserted into said seat for adjusting the degree of opening of said seat, said slow fuel passage opening into the portion defined between said fixed and said variable restriction means.
7. A carburetor, substantially as hereinbefore described with reference to Fig. 1 of the accompanying drawings.
8. A carburetor, substantially as hereinbefore described with reference to Fig. 3 of the accompanying drawings.
9. A carburetor, substantially as herinbefore described with reference to Fig. 4 of the accompanying drawings.
1 0. A carburetor, substantially as hereinbefore described with reference to Fig. 5 of the accompanying drawings.
11. A carburetor, substantially as hereinbefore described with reference to Fig. 6 of the accompanying drawings.
1 2. A carburetor, substantially as hereinbefore described with reference tr. Figs. 1 and 2 of the accompanying drawings.
1 3. A carburetor, substantially as hereinbefore described with reference to Figs. 2 and 3 or Figs. 2 and 4 or Figs. 2 and 5 or Figs. 2 and 6 of the accompaning drawings.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16278781U JPS5867951U (en) | 1981-10-31 | 1981-10-31 | vaporizer |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| GB2108204A true GB2108204A (en) | 1983-05-11 |
Family
ID=15761194
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB08230840A Withdrawn GB2108204A (en) | 1981-10-31 | 1982-10-28 | Carburetor with a sonic idling system for an IC engine |
Country Status (4)
| Country | Link |
|---|---|
| JP (1) | JPS5867951U (en) |
| DE (1) | DE3238171A1 (en) |
| FR (1) | FR2515737A1 (en) |
| GB (1) | GB2108204A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| IT1224457B (en) * | 1988-09-30 | 1990-10-04 | Marco Morini | GROUP FOR THE SUPPLY OF A CARBURATION ENGINE IN SPECIAL OPERATING CONDITIONS |
Family Cites Families (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1881433A (en) * | 1929-08-12 | 1932-10-11 | Marvel Carbureter Co | Carburetor |
| GB1151802A (en) * | 1967-01-12 | 1969-05-14 | British Motor Corp Ltd | Carburetters for Internal Combustion Engines. |
| FR1547734A (en) * | 1967-10-19 | 1968-11-29 | Sibe | Improvements to carburettors for internal combustion engines |
| FR1543621A (en) * | 1967-10-27 | 1968-10-25 | Carburetor | |
| US3711069A (en) * | 1969-08-15 | 1973-01-16 | Ford Motor Co | High velocity carburetor idle system |
| US3878271A (en) * | 1972-05-17 | 1975-04-15 | Alfa Romeo Spa | Device for feeding the air-fuel mixture to an internal combustion engine during idling |
| GB1451100A (en) * | 1973-11-16 | 1976-09-29 | Ford Motor Co | Carburettor idle system |
| FR2268950B1 (en) * | 1974-04-23 | 1979-03-09 | Sibe | |
| JPS53115416A (en) * | 1977-03-18 | 1978-10-07 | Nissan Motor Co Ltd | Variable venturi carburetor |
| DE2817026C2 (en) * | 1978-04-19 | 1983-07-07 | Central'nyj naučno-issledovatel'skij avtomobil'nyj i avtomotornyj institut (NAMI), Moskva | Idle fuel system in a carburetor for internal combustion engines |
| DE2855683C2 (en) * | 1978-12-22 | 1982-12-16 | Pierburg Gmbh & Co Kg, 4040 Neuss | Carburetors for internal combustion engines |
| JPS56126654A (en) * | 1980-03-11 | 1981-10-03 | Nissan Motor Co Ltd | Electronic controlled carburetor |
-
1981
- 1981-10-31 JP JP16278781U patent/JPS5867951U/en active Pending
-
1982
- 1982-10-12 DE DE19823238171 patent/DE3238171A1/en not_active Withdrawn
- 1982-10-22 FR FR8217707A patent/FR2515737A1/en active Pending
- 1982-10-28 GB GB08230840A patent/GB2108204A/en not_active Withdrawn
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5867951U (en) | 1983-05-09 |
| DE3238171A1 (en) | 1983-05-05 |
| FR2515737A1 (en) | 1983-05-06 |
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