CN211315261U

CN211315261U - Oil-filling limited exhaust combined valve for oil tank

Info

Publication number: CN211315261U
Application number: CN201921116008.9U
Authority: CN
Inventors: 吴绪顺; 齐继峰
Original assignee: WUHU SHUNRONG AUTOMOBILE PARTS CO Ltd
Current assignee: WUHU SHUNRONG AUTOMOBILE PARTS CO Ltd
Priority date: 2019-07-16
Filing date: 2019-07-16
Publication date: 2020-08-21
Anticipated expiration: 2029-07-16

Abstract

The utility model discloses an oil filling and quantity limiting exhaust combination valve for an oil tank, which comprises an upper cover, a valve body, a sealing ring, a small floater, a small spring, a big floater assembly, a big spring and a lower cover; this refuel exhaust combination valve of limiting quantity of not only can effectively play the carminative effect of refueling, guarantees the respiratory effect of oil tank, can avoid the vehicle to take place the slope moreover or fuel leaks from the combination valve when the car is turned over.

Description

Oil-filling limited exhaust combined valve for oil tank

Technical Field

The utility model relates to a car fuel tank spare part specifically, relates to an it limits quantity of exhaust combination valve to refuel for oil tank.

Background

Along with the gradual improvement of the national requirements for environmental protection, the national six regulations require that the vehicle-mounted steam recovery system is adopted in the refueling process of the whole vehicle, the system is characterized in that gas in the fuel tank is discharged into the carbon tank through a refueling limit valve in the refueling process, oil steam generated in the process is absorbed by carbon powder in the carbon tank and then discharged into the atmosphere, the oil steam contained in the filtered gas is very little, and the pollution degree to the environment is greatly reduced. When the traditional national five system refuels, the gas in the oil tank is directly discharged into the atmosphere through the refueling exhaust joint, and a large amount of oil vapor is discharged into the atmosphere during refueling, so that the environment is greatly polluted.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a refuel exhaust combination valve of limiting quantity for oil tank, this refuel exhaust combination valve of limiting quantity not only can effectively play and refuel carminative effect, guarantees the respiratory effect of oil tank, and the fuel leaks from the combination valve when can avoiding the vehicle to take place to incline or overturn moreover.

In order to achieve the purpose, the utility model provides an oiling limit exhaust combination valve for an oil tank, which comprises an upper cover, a valve body, a sealing ring, a small floater, a small spring, a large floater assembly, a large spring and a lower cover;

the small spring is sleeved in the small floater, the small floater is arranged on the large floater assembly, the large floater assembly and the small floater are integrally positioned in the valve body and can move up and down in the valve body, the upper end of the valve body is communicated with the upper cover, the lower cover is sleeved outside the valve body and is buckled with the buckling hole of the upper cover through a second buckle, the large spring is arranged in the lower cover, and at least part of the large spring is positioned in the large floater assembly; the lower cover is provided with a window, when fuel enters the lower cover through the window, the fuel can be filled into the valve body and float the large floater assembly, so that the large floater assembly drives the small floater to rise along with the liquid level;

the top of little float is fixed with the sealing ring, the upper end of valve body is provided with circular through hole, circular through hole is in the inside downwardly extending of valve body is formed with the sealing flange face, works as little float rises, the sealing ring can with the laminating of sealing flange face mutually, with will circular through hole shields.

Preferably, the top of valve body still upwards the arch be formed with annular mounting groove, the center of annular mounting groove inwards forms the through hole, the top edge of through hole outwards extends and forms protruding flange face, be provided with little air discharge duct on the protruding flange face, be provided with the video disc in the annular mounting groove, its bottom of video disc under the effect of gravity with protruding flange face laminates mutually, in order will the through hole is sealed.

Preferably, the refueling limit exhaust combination valve further comprises a disc gland in a circular ring shape, the edge of the circular ring of the disc gland extends downwards to form a plurality of buckling grooves, the annular mounting groove is provided with a plurality of first buckles, and the buckling grooves are buckled with the first buckles to buckle and seal the disc in the annular mounting groove.

Preferably, the top of the small floater protrudes upwards to form an annular button structure, the annular button structure is sleeved with a sealing ring, the upper surface of the sealing ring forms a sealing surface, and when the sealing ring is attached to the sealing flange surface, the annular button structure can extend out of the valve body.

Preferably, a plurality of guide rods are fixed on the circumference of the inner wall of the valve body, a plurality of guide grooves are formed in the outer side of the small floater, and the guide rods are at least partially positioned in the guide grooves, so that the small floater can move up and down along the guide rods.

Preferably, the large floater assembly comprises a sealing gasket gland, a sealing gasket and a large floater;

the upper end of the large floater is upwards protruded to form a trapezoidal sealing gasket attaching surface, a sealing gasket installing groove is formed in the sealing gasket attaching surface, the sealing gasket is arranged in the sealing gasket installing groove, a sealing gasket gland installing hole is formed in the upper end of the large floater, and when a circular truncated cone on the sealing gasket gland is inserted into the sealing gasket gland installing hole, the sealing gasket can be tightly pressed in the sealing gasket installing groove;

the bottom of the through hole is provided with a trapezoidal sealing surface, and when the large floater moves upwards, the sealing gasket can be attached to the trapezoidal sealing surface so as to seal the through hole.

Preferably, a semicircular installation groove is formed in the large floater, the small floater is arranged in the semicircular installation groove, a stop block is arranged in the semicircular installation groove, a stop strip is fixed on the small floater, and the small floater is prevented from sliding out of the semicircular installation groove by the mutual limit of the stop block and the stop strip.

Preferably, a cross-shaped bulge is arranged in the lower cover, one end of the large spring is sleeved on the cross-shaped bulge, and the other end of the large spring is sleeved in the large floater;

a plurality of limiting ribs are arranged in the lower cover, and the limiting ribs can prevent the valve body from rotating in the lower cover;

the top of lower cover is equipped with first face of weld, the lateral surface of valve body be provided with first face of weld looks welded fastening's second face of weld.

Preferably, a sealing ring mounting groove is formed in the valve body, and a sealing ring is arranged in the sealing ring mounting groove.

Preferably, the upper cover is provided with a communicating pipe, and the outer side of the communicating pipe is sleeved with a communicating pipe sealing ring.

The utility model provides a refuel exhaust combination valve of limiting quantity of fuel for oil tank, it is right during the fuel tank adds the fuel, rise along with the inside fuel liquid level of fuel tank, cross when the liquid level during the window on the lower cover, the fuel passes through the window gets into inside the lower cover, inside the valve body is filled to the fuel, and will big float assembly floats, big float assembly drives little float rises along with the rising of liquid level together, up to rising to the highest position, the sealing ring at little float top with the laminating of the inside sealed flange face of valve body cuts off exhaust passage, and the valve is in the complete closure state this moment, and the oil tank can't exhaust, refuels and accomplishes. When the liquid level in the oil tank is lower than the window on the lower cover, the large floater assembly descends under the action of gravity, meanwhile, the small floater descends along with the gravity, the sealing ring is separated from the sealing flange surface, and the exhaust channel is opened again. In this case, the tank is allowed to be refilled. Under the condition that the air pressure in the oil tank is greater than the gravity of the disc, the disc can move upwards under the action of the internal air pressure, the disc is separated from the circular sealing surface on the upper surface of the valve body, so that an effective air channel is formed among the valve body, the disc and the upper cover, under the condition that the oil tank is under negative pressure, the disc can move downwards, so that the disc is attached to the circular sealing surface on the upper surface of the valve body, but a plurality of small vent grooves are distributed on the circular sealing surface, a certain gap is formed between the disc and the valve body by the small vent grooves to form an air supplementing channel, and external air can enter the oil tank through the small vent grooves. When the liquid level in the oil tank is higher than the window on the lower cover, the large float assembly rises, the valve body is closed, and the fuel cannot pass through the through hole on the valve body and slosh to the outside. When the liquid level in the oil tank is lower than the window on the lower cover, the large floater assembly descends under the action of gravity, the sealing ring on the small floater is separated from the valve body, an effective exhaust channel is formed between the small floater and the valve body, and air supplement or exhaust can be completed in the oil tank. The utility model provides a refuel limit for quantity of exhaust combination valve has integrated refuel limit for quantity valve and the dual function of gravity valve, when refuel the car, guarantees that the system can be smooth and easy to exhaust, when reaching the rated capacity of oil tank, the valve can be in time closed, accomplishes refuel and guarantees the filling volume; when the automobile is normally used, the fuel system can exhaust and supplement air through the gravity valve under the condition that the oil filling limit valve is closed; under the condition that the refueling limit valve is not closed, the fuel system can exhaust and supplement gas through the combination valve; when the vehicle inclines or turns over, the system is ensured to be sealed, and fuel oil is not leaked. Therefore, the valve actually plays a role in oiling and exhausting, and also plays a role in ensuring the breathing of the oil tank.

Other features and advantages of the present invention will be described in detail in the detailed description which follows.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:

fig. 1 is an exploded view of a fuel filling quantity limiting exhaust combination valve for a fuel tank provided by the present invention;

FIG. 2 is a schematic diagram of the overall configuration of the fuel filling limited exhaust combination valve provided in FIG. 1;

FIG. 3 is a schematic structural diagram of a valve body in the fuel filling limited exhaust combination valve provided in FIG. 1;

FIG. 4 is a schematic structural diagram of a disk gland in the fuel filling limited exhaust combination valve provided in FIG. 1;

FIG. 5 is a schematic diagram of a small float in the combined fuel filling and air venting valve of FIG. 1;

FIG. 6 is a schematic structural diagram of a sealing ring in the combined fuel filling and limited exhaust valve provided in FIG. 1;

FIG. 7 is a schematic view of the internal structure of the valve body of the combined fuel filling and limited exhaust valve provided in FIG. 1;

FIG. 8 is an exploded view of the large float assembly of the refueling limited displacement combination valve provided in FIG. 1;

FIG. 9 is a schematic view of the internal structure of the lower cover of the combined fuel filling and air exhaust valve of FIG. 1;

FIG. 10 is a cross-sectional view of the upper cover of the fuel filling limited exhaust combination valve provided in FIG. 1;

fig. 11 is a structural view of a fueling-limiting exhaust combination valve provided with a small communicating pipe.

Description of the reference numerals

In the figure: 1. an upper cover; 2. a disc gland; 3. a disc; 4. a seal ring; 5. a valve body; 6. a seal ring; 7. a small float; 8. a small spring; 9. a large float assembly; 10. a large spring; 11. a lower cover; 12. A sealing gasket gland; 13. a gasket; 14. a large float; 15. a communicating pipe sealing ring; 16. an annular mounting groove; 17. a through hole; 18. a raised flange face; 19. a small exhaust duct; 20. a first buckle; 21. a fastening groove; 22. an annular button structure; 23. a sealing surface; 24. a circular through hole; 25. sealing the flange face; 26. a guide bar; 27. a guide groove; 28. a semicircular mounting groove; 29. a stop block; 30. a stop bar; 31. A gasket abutting surface; 32. a sealing gasket gland mounting hole; 33. a gasket mounting groove; 34. a circular truncated cone; 35. A guide groove; 36. a trapezoidal sealing surface; 37. a cross-shaped bulge; 38. limiting ribs; 39. a second buckle; 40. a window; 41. a first welding surface; 42. a second weld face; 43. a sealing ring mounting groove; 44. a welding part; 45. a sealing ring matching surface; 46. a snap-in hole; 47. a communicating pipe; 48. a flow oil hole; 49. an exhaust window; 50. a small communicating pipe; 51. and a small communicating pipe seal ring.

Detailed Description

The following detailed description of the embodiments of the present invention will be made with reference to the accompanying drawings. It is to be understood that the description of the embodiments herein is for purposes of illustration and explanation only and is not intended to limit the invention.

As shown in fig. 1-10, the utility model provides an oil filling and quantity limiting exhaust combination valve for an oil tank, which comprises an upper cover 1, a valve body 5, a sealing ring 6, a small float 7, a small spring 8, a large float assembly 9, a large spring 10 and a lower cover 11; the small spring 8 is sleeved in the small floater 7, the small floater 7 is arranged on the large floater assembly 9, the large floater assembly 9 and the small floater 7 are integrally positioned in the valve body 5 and can move up and down in the valve body, the upper end of the valve body 5 is communicated with the upper cover 1, the lower cover 11 is sleeved outside the valve body 5 and is buckled with the buckling hole 46 of the upper cover 1 through a second buckle 39, the large spring 10 is arranged in the lower cover 11, at least part of the large spring 10 is positioned in the large floater assembly 9, and the bottom of the lower cover 11 is provided with an oil flowing hole 48; the lower cover 11 is provided with a window 40, when fuel enters the lower cover 11 through the window 40, the fuel can be filled into the valve body 5, and the large float assembly 9 is floated, so that the large float assembly 9 drives the small float 7 to rise along with the liquid level; the top of little float 7 is fixed with sealing ring 6, the upper end of valve body 5 is provided with circular through hole 24, circular through hole 24 is in inside downwardly extending of valve body 5 is formed with sealing flange face 25, works as little float 7 rises, sealing ring 6 can with sealing flange face 25 is laminated mutually, in order to with circular through hole 24 shields.

When the fuel tank is filled with fuel, the fuel liquid level in the fuel tank rises, when the liquid level overflows through a window in the lower cover, the fuel enters the lower cover through the window, the fuel is filled in the valve body, the large floater assembly floats, the large floater assembly drives the small floater to rise along with the rise of the liquid level until the small floater rises to the highest position, the sealing ring at the top of the small floater is attached to the sealing flange surface in the valve body, the exhaust channel is cut off, the valve is in a completely closed state, the fuel tank cannot exhaust, and the refueling is completed. When the liquid level in the oil tank is lower than the window on the lower cover, the large floater assembly descends under the action of gravity, meanwhile, the small floater descends along with the gravity, the sealing ring is separated from the sealing flange surface, and the exhaust channel is opened again. In this case, the tank is allowed to be refilled. Under the condition that the air pressure in the oil tank is greater than the gravity of the disc, the disc can move upwards under the action of the internal air pressure, the disc is separated from the circular sealing surface on the upper surface of the valve body, so that an effective air channel is formed among the valve body, the disc and the upper cover, under the condition that the oil tank is under negative pressure, the disc can move downwards, so that the disc is attached to the circular sealing surface on the upper surface of the valve body, but a plurality of small vent grooves are distributed on the circular sealing surface, a certain gap is formed between the disc and the valve body by the small vent grooves to form an air supplementing channel, and external air can enter the oil tank through the small vent grooves. When the liquid level in the oil tank is higher than the window on the lower cover, the large float assembly rises, the valve body is closed, and the fuel cannot pass through the through hole on the valve body and slosh to the outside. When the liquid level in the oil tank is lower than the window on the lower cover, the large floater assembly descends under the action of gravity, the sealing ring on the small floater is separated from the valve body, an effective exhaust channel is formed between the small floater and the valve body, and air supplement or exhaust can be completed in the oil tank. The utility model provides a refuel limit for quantity of exhaust combination valve has integrated refuel limit for quantity valve and the dual function of gravity valve, when refuel the car, guarantees that the system can be smooth and easy to exhaust, when reaching the rated capacity of oil tank, the valve can be in time closed, accomplishes refuel and guarantees the filling volume; when the automobile is normally used, the fuel system can exhaust and supplement air through the gravity valve under the condition that the oil filling limit valve is closed; under the condition that the refueling limit valve is not closed, the fuel system can exhaust and supplement gas through the combination valve; when the vehicle inclines or turns over, the system is ensured to be sealed, and fuel oil is not leaked. Therefore, the valve actually plays a role in oiling and exhausting, and also plays a role in ensuring the breathing of the oil tank.

In the utility model discloses a preferred embodiment, the top of valve body 5 still upwards the arch be formed with annular mounting groove 16, the center of annular mounting groove 16 inwards forms through hole 17, the top edge of through hole 17 outwards extends and forms protruding flange face 18, be provided with little exhaust duct 19 on the protruding flange face 18, be provided with video disc 3 in the annular mounting groove 16, video disc 3 receive the effect of gravity its bottom with protruding flange face 18 laminates mutually, with will through hole 17 is sealed.

In a preferred embodiment of the present invention, for better exhaust, the combined valve for fuel filling and exhaust with limited amount further includes a disc gland 3 in a circular ring shape, a plurality of buckle grooves 21 extend downwards from the edge of the circular ring of the disc gland 3, the annular mounting groove 16 is provided with a plurality of first buckles 20, the buckle grooves 21 are buckled with the first buckles 20, so as to buckle the disc 3 in the annular mounting groove 16.

The utility model discloses an in a preferred embodiment, for the leakproofness of the sealing ring at better realization little float top, the top of little float 7 is upwards protruding to be equipped with cyclic annular button structure 22, sealing ring 6 has been cup jointed on the cyclic annular button structure 22, sealing ring 6 upper surface forms sealed face 23, works as sealing ring 6 with when sealed flange face 25 is laminated mutually, cyclic annular button structure 22 can stretch out the outside of valve body 5.

In a preferred embodiment of the present invention, in order to make the small float 7 move up and down more smoothly, a plurality of guide rods 26 are fixed on the circumference of the inner wall of the valve body 5, a plurality of guide grooves 27 are provided on the outer side of the small float 7, the guide rods 26 are at least partially located in the guide grooves 27, so that the small float 7 can move up and down along the guide rods 26.

In a preferred embodiment of the present invention, the large float assembly 9 comprises a gasket gland 12, a gasket 13 and a large float 14; the outer side surface of the large floater 14 is also provided with a second guide groove 35, and a second guide rod matched with the valve body 5 is arranged in the valve body;

the upper end of the large floater 14 protrudes upwards to form a trapezoidal sealing gasket attachment surface 31, a sealing gasket installation groove 33 is formed in the sealing gasket attachment surface 31, the sealing gasket 13 is arranged in the sealing gasket installation groove 33, a sealing gasket gland installation hole 32 is further formed in the upper end of the large floater 14, and when the circular truncated cone 34 on the sealing gasket gland 12 is inserted into the sealing gasket gland installation hole 32, the sealing gasket 13 can be tightly pressed in the sealing gasket installation groove 33;

the bottom of the through hole 17 is provided with a trapezoidal sealing surface 36, and when the large float 14 moves upwards, the sealing gasket 13 can be attached to the trapezoidal sealing surface 36 to seal the through hole 17.

In a preferred embodiment of the present invention, for better setting the small float on the large float, a semicircular installation groove 28 is provided on the large float 14, the small float 7 is disposed in the semicircular installation groove 28, a stop block 29 is disposed in the semicircular installation groove 28, a stop strip 30 is fixed on the small float 7, through the stop block 29 and the stop strip 30 are mutually limited to prevent the small float 7 from sliding out of the semicircular installation groove 28.

In a preferred embodiment of the present invention, in order to better realize the connection between the lower cover 11 and the valve body 5, a cross-shaped protrusion 37 is disposed inside the lower cover 11, one end of the large spring 10 is sleeved on the cross-shaped protrusion 37, and the other end thereof is sleeved inside the large float 14;

a plurality of limiting ribs 38 are arranged inside the lower cover 11, and the limiting ribs 38 can prevent the valve body 5 from rotating in the lower cover 11;

the top of the lower cover 11 is provided with a first welding surface 41, and the outer side surface of the valve body 5 is provided with a second welding surface 42 welded and fixed with the first welding surface 41.

In a preferred embodiment of the present invention, in order to increase the sealing performance of the valve body 5, a sealing ring mounting groove 43 is provided on the valve body 5, and a sealing ring 4 is provided in the sealing ring mounting groove 43.

In a preferred embodiment of the present invention, the upper cover 1 is provided with a communication pipe 47, and the outside of the communication pipe 47 is sleeved with a communication pipe seal ring 15. The upper cover 1 is formed by injection molding of two materials, wherein the two materials comprise a welding piece 44 and a main material for the upper cover 1, and the main material has good permeation and discharge resistance. The two materials are bonded together in a chemical connection mode, and defects of layering, bubbles and the like can be avoided. A communication pipe 47 is preferably disposed on the upper cover 1, and an annular communication pipe sealing ring 15 may be preferably disposed on the connection pipe 47. A small communication pipe 50 may also be preferably disposed on the upper cover 1, and a small communication pipe sealing ring 51 may also be preferably disposed on the small communication pipe 50.

The preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, however, the present invention is not limited to the details of the above embodiments, and the technical concept of the present invention can be within the scope of the present invention to perform various simple modifications to the technical solution of the present invention, and these simple modifications all belong to the protection scope of the present invention.

It should be noted that the various technical features described in the above embodiments can be combined in any suitable manner without contradiction, and in order to avoid unnecessary repetition, the present invention does not need to describe any combination of the features.

In addition, various embodiments of the present invention can be combined arbitrarily, and the disclosed content should be regarded as the present invention as long as it does not violate the idea of the present invention.

Claims

1. The combined valve for the oil filling and the exhaust limiting is characterized by comprising an upper cover (1), a valve body (5), a sealing ring (6), a small floater (7), a small spring (8), a large floater assembly (9), a large spring (10) and a lower cover (11);

the small spring (8) is sleeved in the small floater (7), the small floater (7) is arranged on the large floater assembly (9), the large floater assembly (9) and the small floater (7) are integrally positioned in the valve body (5) and can move up and down in the valve body, the upper end of the valve body (5) is communicated with the upper cover (1), the lower cover (11) is sleeved outside the valve body (5) and is buckled with a buckling hole (46) of the upper cover (1) through a second buckle (39), the large spring (10) is arranged in the lower cover (11), at least part of the large spring (10) is positioned in the large floater assembly (9), and a flow oil hole (48) is formed in the bottom of the lower cover (11); the lower cover (11) is provided with a window (40), when fuel enters the lower cover (11) through the window (40), the fuel can be filled into the valve body (5) and float the large floater assembly (9), so that the large floater assembly (9) drives the small floater (7) to rise along with the liquid level;

the top of little float (7) is fixed with sealing ring (6), the upper end of valve body (5) is provided with circular through hole (24), circular through hole (24) are in valve body (5) inside downwardly extending is formed with sealing flange face (25), works as little float (7) rise, sealing ring (6) can with sealing flange face (25) are laminated mutually, with will circular through hole (24) shield.

2. The combination valve for adding oil and limiting exhaust of claim 1, wherein the top of the valve body (5) is further protruded upwards to form an annular mounting groove (16), the center of the annular mounting groove (16) is inwardly provided with a through hole (17), the top edge of the through hole (17) extends outwards to form a protruded flange surface (18), the protruded flange surface (18) is provided with a small exhaust groove (19), the annular mounting groove (16) is internally provided with a disc (3), and the bottom of the disc (3) is attached to the protruded flange surface (18) under the action of gravity to seal the through hole (17).

3. The combined valve for oil filling and gas emission limiting as claimed in claim 2, further comprising a circular disc gland (2), wherein a plurality of snap grooves (21) extend downwards from the edge of the circular ring of the disc gland (2), the annular mounting groove (16) is provided with a plurality of first snaps (20), and the snap grooves (21) are snapped with the first snaps (20) to snap the disc (3) into the annular mounting groove (16).

4. The combined valve for fuel filling and air exhaust with limited quantity according to claim 3 is characterized in that the top of the small float (7) is provided with an annular button structure (22) in a protruding manner, a sealing ring (6) is sleeved on the annular button structure (22), a sealing surface (23) is formed on the upper surface of the sealing ring (6), and when the sealing ring (6) is jointed with the sealing flange surface (25), the annular button structure (22) can extend out of the valve body (5).

5. The combined valve for fuel filling and limited exhaust as claimed in claim 4, characterized in that a plurality of guide rods (26) are fixed on the circumference of the inner wall of the valve body (5), a plurality of guide grooves (27) are arranged on the outer side of the small float (7), and the guide rods (26) are at least partially positioned in the guide grooves (27), so that the small float (7) can move up and down along the guide rods (26).

6. The combined valve for fuel filling and air exhaust of claim 5, wherein the large float assembly (9) comprises a gasket gland (12), a gasket (13) and a large float (14);

the upper end of the large floater (14) protrudes upwards to form a trapezoidal sealing gasket attaching surface (31), a sealing gasket mounting groove (33) is formed in the sealing gasket attaching surface (31), the sealing gasket (13) is arranged in the sealing gasket mounting groove (33), a sealing gasket gland mounting hole (32) is further formed in the upper end of the large floater (14), and when the round platform (34) on the sealing gasket gland (12) is inserted into the sealing gasket gland mounting hole (32), the sealing gasket (13) can be tightly pressed in the sealing gasket mounting groove (33);

the bottom of the through hole (17) is provided with a trapezoidal sealing surface (36), and when the large floater (14) moves upwards, the sealing gasket (13) can be attached to the trapezoidal sealing surface (36) so as to seal the through hole (17).

7. The combined valve for refueling and limited exhaust of claim 6, characterized in that a semicircular installation groove (28) is formed in the large float (14), the small float (7) is arranged in the semicircular installation groove (28), a stop block (29) is arranged in the semicircular installation groove (28), a stop strip (30) is fixed on the small float (7), and the small float (7) is prevented from sliding out of the semicircular installation groove (28) by mutual limiting of the stop block (29) and the stop strip (30).

8. The combined valve for fuel filling and exhaust with limited quantity according to claim 7 is characterized in that a cross-shaped bulge (37) is arranged inside the lower cover (11), one end of the large spring (10) is sleeved on the cross-shaped bulge (37), and the other end of the large spring is sleeved inside the large float (14);

a plurality of limiting ribs (38) are arranged inside the lower cover (11), and the limiting ribs (38) can prevent the valve body (5) from rotating in the lower cover (11);

the top of lower cover (11) is equipped with first face of weld (41), the lateral surface of valve body (5) be provided with first face of weld (41) looks welded fastening's second face of weld (42).

9. The combined valve for adding oil and limiting exhaust of claim 8 is characterized in that a sealing ring installation groove (43) is arranged on the valve body (5), and a sealing ring (4) is arranged in the sealing ring installation groove (43).

10. The combined valve for filling oil and limiting exhaust gas as claimed in claim 9, wherein a communicating pipe (47) is arranged on the upper cover (1), and a communicating pipe sealing ring (15) is sleeved on the outer side of the communicating pipe (47).