Combination valve

Abstract

A first discharge port and a second discharge port are formed in the upper end of a valve body, a single-floater valve element assembly and a sealing assembly are arranged in a valve element containing cavity of the valve body, and a pressure maintaining part communicated with the second discharge port is further arranged on the top face of the valve body so as to limit the pressure needed by discharge and circulation from the second discharge port; the single-float valve element assembly is configured to drive the sealing assembly to float upwards to close the first discharge port when the oil tank is filled with oil, and the single-float valve element assembly closes the communication channel and the second discharge port. After refueling and gun jumping, oil in the oil tank is balanced, the difference between the gravity of the single-float valve element assembly and the buoyancy of the oil is larger than the opening force needed by the communication channel and smaller than the opening pressure needed by the first discharge port, the second discharge port is opened, and the first discharge port is kept closed. The functions of a refueling limiting valve and a turnover valve are achieved, only one valve element is needed, the size of the whole valve is similar to that of a common refueling limiting valve, and the use area on an oil tank is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of fuel tank valves, and in particular relates to a combination valve. Background Art

[0002] At present, fuel tanks on the market generally have these two requirements: 1. Refueling limit (overfilling is prohibited); 2. The fuel tank can be vented normally under certain circumstances: when there is positive pressure in the fuel tank, the pressure can be released in time, or when there is negative pressure in the fuel tank, the fuel tank can be replenished in time. In general, in order to meet the above requirements of the fuel tank, a fuel tank needs to be equipped with a refueling limit valve and at least one rollover valve. Gradually, some new designs have appeared in the market. A fuel tank valve can meet the two functional requirements mentioned above at the same time, integrating the functions of the two valves into one product, so that the number of valves required to be configured in the fuel tank can be reduced, and it is also easier to layout on the fuel tank. We generally call it a combination valve, that is, the refueling limit valve and the rollover valve are combined together, so that one product has both functions.

[0003] With the promulgation of the "National VI" regulations, the requirements for evaporative emissions of the entire fuel system have become increasingly stringent, and the requirements for dynamic leakage of fuel tanks (generally including horizontal shaking tests, angle flip shaking tests and six-axis shaking tests, etc.) have also increased. This has put a certain test on the design of the valve, whether it is a refueling limit valve or a flip valve or a combination valve, because these valves are installed and fixed on the fuel tank, the valve core is connected to the inside of the fuel tank, and the valve nozzle is generally connected to the carbon canister through a pipeline. When the vehicle fluctuates during driving, the fuel in the fuel tank will also surge. If the valve core inside the valve cannot seal the exhaust channel in time at this time, there is a certain probability that the fuel will flip out of the valve exhaust channel and flow out through the nozzle, forming a leakage phenomenon.

[0004] There are two main types of combination valves on the market. One type is: the combination valve is relatively large as a whole, with the valve core of the refueling limit valve on one side and the valve core of the flip valve on the other side. The two do not interfere with each other, but because the two valve cores are separate, the combination valve is much larger than an ordinary refueling limit valve, so the cost will be relatively high, and it is also relatively difficult to layout on the fuel tank. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a combination valve to solve the problem that the existing combination valve adopts two valve cores resulting in excessive volume.

[0006] To solve the above problems, the technical solution of the present invention is:

[0007] A combination valve of the present invention comprises a valve body, a valve core part and a pressure maintaining part;

[0008] The valve body is provided with a valve core accommodating cavity, the valve body is provided with at least one inflow channel communicating with the valve core accommodating cavity, and the upper end of the valve body is provided with a first discharge port and a second discharge port communicating with the valve core accommodating cavity;

[0009] The valve core part includes a single float valve core assembly and a sealing assembly; the sealing assembly is provided with a communication channel for connecting the inflow channel of the second discharge port, and the communication channel is smaller than the first discharge port; the single float valve core assembly is slidably connected to the valve core accommodating cavity, the single float valve core assembly is configured to drive the sealing assembly to open or close the first discharge port under the buoyancy of the oil, and the single float valve core assembly is configured to open or close the communication channel when the first discharge port is closed;

[0010] The pressure-maintaining portion is disposed on the top surface of the valve body, and an input end thereof is communicated with the second discharge port, and is used to limit the pressure required to discharge the fluid from the second discharge port;

[0011] In the refueling state, the single float valve core assembly drives the sealing assembly to float up and close the first discharge port under the action of the buoyancy of the oil and the tank pressure, and the single float valve core assembly closes the connecting passage and the second discharge port, and the refueling gun jumps to realize the refueling limiting function; after the refueling gun jumps, the oil in the tank is balanced, the gravity of the single float valve core assembly is greater than the buoyancy of the oil, the difference between the gravity of the single float valve core assembly and the buoyancy of the oil is the gravity difference, the gravity difference is greater than the opening force required for the connecting passage, and the gravity difference is less than the opening pressure required for the first discharge port, the second discharge port is opened, and the first discharge port remains closed to realize the exhaust function.

[0012] In the combined valve of the present invention, the single-float valve core assembly comprises a connected small float section and a large float section, the small float section is located above the large float section, and the large float section is slidably connected to the valve core accommodating chamber; the sealing assembly is slidably connected to the valve core accommodating chamber and is located above the single-float valve core assembly, and is used to cooperate with the large float section and / or the small float section to switch the first discharge port; the sealing assembly is also provided with a connecting channel for connecting the second discharge port and the inflow channel, and is used to cooperate with the small float section to switch the second discharge port, and the connecting channel is smaller than the first discharge port;

[0013] Wherein, at least one downwardly extending lap joint is arranged on the sealing assembly, and the lap joint end of the downwardly extending lap joint is located outside the small float section in the horizontal direction; and an lap joint matching piece matching the lap joint end of the downwardly extending lap joint is arranged on the upper part of the small float section.

[0014] In the combined valve of the present invention, the single float valve core assembly further comprises a movable member, which is rotatably connected to the top surface of the small float section and is used for opening and closing the communication channel.

[0015] In the combination valve of the present invention, the single float valve core assembly further comprises an elastic member, a first end of the elastic member is connected to the valve body, and a second end of the elastic member is connected to the small float section and / or the large float section.

[0016] The combined valve of the present invention, the sealing assembly comprises a sliding member and a sealing member;

[0017] The sliding member is slidably connected to the valve core accommodating chamber, and the sealing member is installed on the sliding member; the sealing member is provided with the communicating channel and a sealing block for sealing the first discharge port;

[0018] The sliding member is driven by the large float section and / or the small float section to slide up and down, and cooperates with the sealing block to open and close the first outlet; the connecting channel connected to the second outlet is used to cooperate with the small float section to open and close the second outlet.

[0019] In the combined valve of the present invention, the sealing block comprises a large sealing ring, a middle sealing ring and a small sealing ring; the large sealing ring and the middle sealing ring are both arranged on the upper surface of the sealing member and correspond to the large discharge port; the large sealing ring is sleeved on the large discharge port; the middle sealing ring is located between the large discharge port and the small discharge port; the small sealing ring is arranged on the lower surface of the sealing member, and the small sealing ring is communicated with the middle sealing ring to cooperate to form the communicating channel.

[0020] The combination valve of the present invention, the downwardly extending lap joint comprises a vertically extending member and a lateral lap joint protrusion;

[0021] The upper end of the vertical extension piece is connected to the sealing assembly, and the lower end of the vertical extension piece is located away from the small float section; the lateral overlapping protrusion is arranged at the lower end of the vertical extension piece and is arranged toward the small float section.

[0022] In the combined valve of the present invention, the overlapping matching piece is a lateral annular protrusion arranged around the small float section.

[0023] In the combination valve of the present invention, the pressure-maintaining part includes a pressure-maintaining shell and a pressure-maintaining cover; a accommodating space is provided in the pressure-maintaining shell, and an inlet hole and a discharge hole connected to the accommodating space are also provided on the pressure-maintaining shell; the pressure-maintaining shell is provided on the top surface of the valve body, and the inlet hole is connected to the second discharge port; the pressure-maintaining cover is slidably connected to the accommodating space and is used to open and close the inlet hole.

[0024] The combination valve of the present invention further comprises a connecting flange; the connecting flange is connected to the valve body and cooperates with the top surface of the valve body to form a fluid discharge chamber for guiding the fluid discharged from the first discharge port and the pressure maintaining portion.

[0025] The combined valve of the present invention, the valve body comprises an outer shell with an upward opening and a transfer shell with a downward opening; the outer shell is sleeved on the lower end of the transfer shell and is fixedly connected to the transfer shell;

[0026] The inner wall surface of the adapter shell cooperates with the bottom surface of the outer shell to form the valve core accommodating chamber; at least one first connecting port is opened on the shell of the outer shell, and the first connecting port, the outer wall surface of the adapter shell and the inner wall surface of the outer shell cooperate to form an inflow channel connected to the valve core accommodating chamber.

[0027] Due to the adoption of the above technical solution, the present invention has the following advantages and positive effects compared with the prior art:

[0028] In one embodiment of the present invention, a first discharge port and a second discharge port are arranged at the upper end of the valve body, a single float valve core assembly and a sealing assembly are arranged in the valve core accommodating chamber of the valve body, and a pressure retaining portion connected to the second discharge port is further arranged on the top surface of the valve body to limit the pressure required for discharge from the second discharge port; the single float valve core assembly is configured so that when the oil tank is refueled, the single float valve core assembly drives the sealing assembly to float up and close the first discharge port under the action of the buoyancy of the oil and the pressure of the oil tank, and the single float valve core assembly closes the connecting passage and the second discharge port; after the oil tank is refueled and the gun jumps, the oil in the oil tank is balanced, and the single float valve core assembly The gravity of the float valve core assembly is greater than the buoyancy of the oil, and the difference between the gravity of the single float valve core assembly and the buoyancy of the oil is the gravity difference. Since the connecting channel is set to be smaller than the first outlet, the opening performance between the connecting channel and the single float valve core assembly under high pressure is better, so that the gravity difference can be greater than the opening force required by the connecting channel and less than the opening pressure required by the first outlet, thereby realizing the function of opening the second outlet and keeping the first outlet closed; and when the oil level in the valve body drops, the single float valve core assembly can drive the sealing assembly to move down and open the first outlet. Thus, the functions of the refueling limit valve and the flip valve are realized, and only one valve core is used. The size of the overall valve is similar to that of an ordinary refueling limit valve, which reduces the use area of ​​the combination valve on the oil tank, facilitates the layout of the oil tank during design, and reduces costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is a schematic diagram of a combination valve of the present invention;

[0030] Figure 2 It is a schematic diagram of a first working state of the combination valve of the present invention;

[0031] Figure 3It is a schematic diagram of a second working state of the combination valve of the present invention;

[0032] Figure 4 It is a schematic diagram of the third working state of the combination valve of the present invention;

[0033] Figure 5 It is a schematic diagram of a fourth working state of the combination valve of the present invention;

[0034] Figure 6 It is a schematic diagram of the fifth working state of the combination valve of the present invention;

[0035] Figure 7 It is a schematic diagram of the sixth working state of the combination valve of the present invention.

[0036] Explanation of the reference numerals in the accompanying drawings: 1. outer shell; 2. adapter shell; 201. barrier member; 3. large float section; 4. small float section; 5. vertical extension member; 6. lateral overlap protrusion; 7. lateral annular protrusion; 8. connecting channel; 9. first discharge outlet; 10. second discharge outlet; 11. large sealing ring; 12. medium sealing ring; 13. small sealing ring; 14. spring; 15. connecting flange; 16. pressure maintaining shell; 17. pressure maintaining cover; 18. movable part. DETAILED DESCRIPTION

[0037] The advantages and features of the present invention will become more apparent from the following description and claims.

[0038] See also Figure 1 In one embodiment, a combined valve includes a valve body, a valve core portion and a pressure-maintaining portion. A valve core accommodating cavity is provided in the valve body, at least one inflow channel connected to the valve core accommodating cavity is provided on the valve body, and a first discharge port 9 and a second discharge port 10 connected to the valve core accommodating cavity are provided at the upper end of the valve body.

[0039] The valve core part includes a single float valve core assembly and a sealing assembly. The sealing assembly is provided with a communication channel 8 for connecting the inflow channel of the second discharge port 10, and the communication channel 8 is smaller than the first discharge port 9. The single float valve core assembly is slidably connected to the valve core accommodating cavity, and the single float valve core assembly is configured to drive the sealing assembly to open or close the first discharge port 9 under the buoyancy of the oil, and the single float valve core assembly is configured to open or close the communication channel 8 when the first discharge port 9 is closed.

[0040] The pressure-maintaining portion is disposed on the top surface of the valve body, and the input end thereof is communicated with the second discharge port 10 , so as to limit the pressure required for discharging the fluid from the second discharge port 10 .

[0041] In the refueling state, the single float valve core assembly drives the sealing assembly to float up and close the first discharge port 9 under the action of the oil buoyancy and the oil tank pressure, and the single float valve core assembly closes the connecting channel 8 and the second discharge port 10. After the refueling gun jumps, the oil in the tank is balanced, the gravity of the single float valve core assembly is greater than the oil buoyancy, and the difference between the gravity of the single float valve core assembly and the oil buoyancy is the gravity difference. The gravity difference is greater than the opening force required for the connecting channel 8, and the gravity difference is less than the opening pressure required for the first discharge port 9. The second discharge port 10 is opened, and the first discharge port 9 remains closed.

[0042] In this embodiment, a first discharge port 9 and a second discharge port 10 are arranged at the upper end of the valve body, and a single float valve core assembly and a sealing assembly are arranged in the valve core accommodating cavity of the valve body, and a pressure-maintaining portion connected to the second discharge port 10 is further arranged on the top surface of the valve body to limit the pressure required for discharge from the second discharge port 10; the single float valve core assembly is configured so that when the oil tank is refueled, the single float valve core assembly drives the sealing assembly to float up and close the first discharge port 9 under the action of the buoyancy of the oil and the pressure of the oil tank, and the single float valve core assembly closes the connecting channel 8 and the second discharge port 10; after the oil tank jumps out of the gun during refueling, the oil in the oil tank is balanced, and the single float valve core assembly is closed. The gravity of the sub-valve core assembly is greater than the buoyancy of the oil, and the difference between the gravity of the single-float valve core assembly and the buoyancy of the oil is the gravity difference. Since the connecting channel 8 is set to be smaller than the first discharge port 9, the opening performance between the connecting channel 8 and the single-float valve core assembly under high pressure is better, so that the gravity difference can be greater than the opening force required by the connecting channel 8 and less than the opening pressure required by the first discharge port 9, thereby realizing the function of opening the second discharge port 10 and keeping the first discharge port 9 closed; and when the oil level in the valve body drops, the single-float valve core assembly can drive the sealing assembly to move downward to open the first discharge port 9. Thus, the functions of the refueling limit valve and the flip valve are realized, and only one valve core is used. The size of the overall valve is similar to that of an ordinary refueling limit valve, which reduces the use area of ​​the combination valve on the oil tank, facilitates the layout of the oil tank during design, and reduces costs.

[0043] The specific structure of the combination valve of this embodiment is further described below:

[0044] In this embodiment, the single float valve core assembly may specifically include a connected small float section 4 and a large float section 3 (the small float section 4 and the large float section 3 cooperate to form an integrated float, and the large and small here mainly refer to the size of the cross-sectional area), the small float section 4 is located above the large float section 3, and the large float section 3 is slidably connected to the valve core accommodating cavity. The sealing assembly is slidably connected to the valve core accommodating cavity and is located above the single float valve core assembly, and is used to cooperate with the large float section 3 and / or the small float section 4 to switch the first discharge port 9. The sealing assembly is also provided with a connecting channel 8 for connecting the second discharge port 10 and the inflow channel, and is used to cooperate with the small float section 4 to switch the second discharge port 10, and the connecting channel 8 is smaller than the first discharge port 9.

[0045] Among them, at least one downward-extending lap joint is provided on the sealing assembly, and the lap joint end of the downward-extending lap joint is located outside the small float section 4 in the horizontal direction. The upper part of the small float section 4 is provided with an lap joint matching piece that matches the lap joint end of the downward-extending lap joint (the purpose of setting the small float section 4 is to form a gap with the valve core accommodating cavity, so that the downward-extending lap joint can extend downward to the side of the small float section 4, and then the lap joint end of the downward-extending lap joint can reach the bottom of the lap joint matching piece, so that the two can be overlapped).

[0046] In this embodiment, in order to further reduce the opening pressure required at the connecting passage 8, the single float valve core assembly may also include a movable member 18, which is rotatably connected to the top surface of the small float section 4, and is used to switch the connecting passage 8. Regarding the connection mode between the movable member 18 and the small float section 4, a connecting shaft can be set on the small float section 4, and a connecting groove for sleeved with the connecting shaft is set at the first end of the movable member 18, and the connecting shaft can rotate and move up and down freely in the connecting groove, and the size of the opening of the connecting groove is smaller than the diameter of the connecting shaft. By setting the movable connection between the movable member 18 and the small float section 4 as the connection between the connecting groove and the connecting shaft, and setting the opening of the connecting groove smaller, so that the connecting shaft cannot be separated, and setting the size of the connecting groove inside the opening larger, so that the movable member 18 can achieve a certain degree of up and down movement relative to the small float section 4, so as to facilitate the opening of the connecting passage 8, of course, the connection between the movable member 18 and the small float section 4 can also be adopted in other ways, which are not specifically limited here.

[0047] Furthermore, a recessed groove may be provided on the top surface of the small float section 4, and the movable member 18 may be provided to be rotatably connected in the recessed groove, that is, the connecting shaft is also arranged in the recessed groove.

[0048] The movable part 18 is used to open the valve core in time to relieve the pressure in the fuel tank when the entire valve core is in a closed state (the single float valve core assembly forms a seal with the sealing assembly, and the entire single float valve core assembly closes the valve core due to the buoyancy in the fuel tank or the shaking of the fuel tank). In some cases, the fuel tank may be filled with a certain amount of pressure. At this time, the valve core needs to be opened in time to relieve the pressure in the fuel tank. Since P = F / S, when F is constant, the larger S is, the smaller P is. That is to say, when there is a higher pressure in the fuel tank, since the cross-sectional area S of the large hole on the sealing assembly is larger, it will only open under a lower pressure. At this time, it is necessary to open it in time through the small hole under the sealing assembly (i.e., the connecting channel 8) to relieve the pressure in the fuel tank. The combination of the movable part 18 and the small float section 4 is to make it easier to open after sealing with the small hole, so as to achieve the pressure relief in the fuel tank. Therefore, the combined structure of the movable part 18 and the small float section 4 can be diverse, and its purpose is to achieve the function of making it easier to reopen the small hole.

[0049] In this embodiment, the single float valve core assembly may further include an elastic member, a first end of the elastic member is connected to the valve body, and a second end of the elastic member is connected to the small float section 4 and / or the large float section 3 . The elastic member may specifically be a spring 14 .

[0050] In this embodiment, the sealing assembly may specifically include a sliding member and a sealing member (the sealing member may be made of a flexible material).

[0051] The sliding member is slidably connected to the valve core accommodating chamber (the sliding connection method can be to open a guide groove on the sliding member and set a corresponding guide protrusion in the valve core accommodating chamber), and the sealing member is installed on the sliding member (the sliding member can be provided with an intermediate through hole, and the sealing member is installed on the intermediate through hole). The sealing member is provided with a communication channel 8 and a sealing block for sealing the first discharge port 9.

[0052] The sliding member is driven by the large float section 3 and / or the small float section 4 to slide up and down, and cooperates with the sealing block to open and close the first outlet 9. The connecting channel 8 connected to the second outlet 10 is used to cooperate with the small float section 4 to open and close the second outlet 10.

[0053] Specifically, the sealing block includes a large sealing ring 11, a medium sealing ring 12 and a small sealing ring 13. The large sealing ring 11 and the medium sealing ring 12 are both arranged on the upper surface of the sealing member, and correspond to the first discharge port 9. The large sealing ring 11 is sleeved on the first discharge port 9. The medium sealing ring 12 is located between the first discharge port 9 and the small discharge port. The small sealing ring 13 is arranged on the lower surface of the sealing member, and the small sealing ring 13 is connected to the medium sealing ring 12 to cooperate in forming a connecting channel 8 (of course, in other embodiments, the arrangement of the sealing block, the sealing member and the sliding member may also be various, for example, part of the sealing member or the sealing block may be arranged on the top surface of the valve core accommodating cavity, and the physical structure on the sliding member may also be used to achieve sealing).

[0054] That is, the diameter of the large sealing ring 11 needs to be larger than the maximum diameter of the first outlet 9, and the diameter of the middle sealing ring 12 needs to be smaller than the minimum diameter of the first outlet 9 and larger than the maximum diameter of the small outlet. This arrangement is to ensure that when the sliding member is in the closed position, it can be close to the top surface of the inner cavity of the valve body and the wall surface inside and outside the first outlet 9 to achieve sealing of the first outlet 9.

[0055] After the first discharge port 9 is sealed, the small discharge port is connected to the inner cavity of the valve body through the above-mentioned communication channel 8. In order to seal the small discharge port, a small sealing ring 13 is provided on the lower end surface of the sealing member, and the diameter of the small sealing ring 13 needs to match the diameter of the communication channel 8. When the small float segment 4 rises, the small sealing ring 13 can contact the top surface of the small float segment 4 (specifically, the above-mentioned movable member 18) and seal the small discharge port.

[0056] In this embodiment, in order to achieve stable overlapping, the downward extending overlapping member may specifically include a vertical extending member 5 and a lateral overlapping protrusion 6 .

[0057] The upper end of the vertical extension member 5 (specifically, it may be rod-shaped) is connected to the above-mentioned sliding member (the specific connection position may be at the bottom edge of the sliding member), and the lower end of the vertical extension member 5 is located away from the small float segment 4 (that is, located on the outside of the small float segment 4 in the horizontal direction), and the lateral overlap protrusion 6 is arranged at the lower end of the vertical extension member 5 and is arranged toward the small float segment 4, that is, there is an interference portion between the lateral overlap protrusion 6 and the overlap matching member in the axial direction, so that when the large float segment 3 and the small float segment 4 slide down as a whole, the overlap matching member can abut against the top surface of the lateral overlap protrusion 6 from above, and drive the sealing assembly to move downward as a whole under the action of the gravity of the two float segments, thereby opening the first discharge port 9.

[0058] Furthermore, the above-mentioned overlapping matching piece is a lateral annular protrusion 7 arranged around the small float section 4.

[0059] In this embodiment, the combination valve may further include a connecting flange 15, which is used to connect to an external pipeline to guide the gas discharged from the two discharge ports to the external pipeline for processing. The connecting flange 15 can be sleeved on the valve body and cooperate with the top surface of the valve body to form a fluid discharge chamber. At this time, the first discharge port 9 and the pressure holding part are located in the fluid discharge chamber to guide the fluid discharged from the first discharge port 9 and the pressure holding part. The connection method of the connecting flange 15 and the valve body can be welding or other fixed connection methods, and a sealing ring needs to be further used for sealing when necessary.

[0060] In the present embodiment, the pressure-maintaining part specifically includes a pressure-maintaining shell 16 and a pressure-maintaining cover 17. A accommodating space is provided in the pressure-maintaining shell 16, and an inlet hole and a discharge hole connected to the accommodating space are also provided on the pressure-maintaining shell 16. The pressure-maintaining shell 16 is provided on the top surface of the valve body, and the inlet hole is connected to the second discharge port 10. The pressure-maintaining cover 17 is slidably connected to the accommodating space and is used to switch the inlet hole. That is, the pressure-maintaining cover 17 is pressed on the inlet hole of the accommodating space by its own gravity to close the inlet hole. After the gas pressure in the valve core accommodating cavity reaches a level that can offset the gravity of the pressure-maintaining cover 17, the pressure-maintaining cover 17 can be pushed to rise, so that the gas can enter the accommodating space through the inlet hole and be discharged through the discharge hole to the fluid discharge chamber formed by the connecting flange 15.

[0061] In this embodiment, the valve body may specifically include an outer shell 1 with an opening facing upward and an adapter shell 2 with an opening facing downward. The outer shell 1 is sleeved on the lower end of the adapter shell 2 and is fixedly connected to the adapter shell 2. The inner wall surface of the adapter shell 2 cooperates with the inner cavity bottom surface of the outer shell 1 to form a valve core accommodating cavity. In addition, the outer shell 1 and the adapter shell 2 may cooperate to form the three aforementioned inflow channels, namely, a first inflow channel, a second inflow channel, and a third inflow channel.

[0062] Among them, at least one first connection port is opened on the shell of the housing 1, and the first connection port, the outer wall surface of the adapter shell 2 and the inner wall surface of the housing 1 cooperate to form a third inflow channel connected to the valve core accommodating cavity. That is, after the oil enters the interior of the housing 1 through the first connection port, it can flow to the bottom surface of the inner cavity of the housing 1 through the gap between the housing 1 and the adapter shell 2 under the action of gravity, thereby gradually filling the valve core accommodating cavity and providing buoyancy for the first single-float valve core assembly and the second single-float valve core assembly.

[0063] The housing of the adapter shell 2 is provided with at least one second connection port connected to the valve core accommodating chamber, and the first connection port and the second connection port cooperate to form a first inflow channel. The second connection port is usually required to be located higher than the first connection port to prevent the oil flowing in through the first connection port from entering the valve core accommodating chamber through the second connection port. When the pressure in the fuel tank increases, the gas will enter the valve core accommodating chamber through the first inflow channel and be discharged through the first discharge port 9 and the second discharge port 10 at the top to reduce the pressure in the fuel tank.

[0064] At least one third connection port is provided on the housing 1, and at least one fourth connection port connected to the valve core accommodating chamber is provided on the shell of the adapter shell 2. The third connection port, the fourth connection port and the connecting channel 8 of the sealing assembly cooperate to form a second inflow channel. The height of the third connection port and the fourth connection port both need to be higher than the first inflow channel. The preferred method is to be close to the top of the housing 1 and the adapter shell 2, so that when the oil level in the valve core accommodating chamber is high, the gas in the fuel tank can still flow into the valve core accommodating chamber through the second inflow channel, and form pressure on the pressure holding part through the second discharge port 10, so as to open the pressure holding part to discharge the gas.

[0065] Furthermore, the first connection port, the second connection port, the third connection port and the fourth connection port can be through holes respectively arranged on the outer shell 1 or the adapter shell 2, and the specific size and shape can be determined according to actual needs and are not specifically limited here.

[0066] Furthermore, a barrier 201 may be provided on the third inflow channel to limit the flow area of ​​the third inflow channel. When the inflow pressure of the oil is constant, the oil flowing into the valve core accommodating chamber will be reduced.

[0067] In this embodiment, the large float section 3 is slidably connected to the valve core accommodating chamber. The specific connection method can be that a plurality of vertically arranged guide rails can be arranged on the inner wall surface of the adapter shell 2, and a corresponding slide groove is arranged on the large float section 3, and the large float section 3 is slidably connected to the guide rail through the slide groove.

[0068] The operating principle of the combination valve of this embodiment in various states is described below:

[0069] 1. The fuel tank realizes the exhaust function through the refueling limit valve in the combination valve. Figure 2 This situation is generally when the fuel tank is not full of fuel, or it can be understood that there is not enough fuel in the fuel tank to submerge the valve core. At this time, the large float section 3 and the small float section 4 are in a dropped state, and the large hole on the sealing component and the first discharge port 9 on the valve body do not form a seal. At this time, the gas inside the fuel tank can be discharged through the first discharge port 9 (at this time, the combination valve plays the function of a refueling limit valve).

[0070] Second, the combination valve realizes the refueling limit (refueling gun jumping) function of the refueling limit valve. Generally, there are two situations to realize the refueling gun jumping of the fuel tank. But in general, after the first row of outlets 9 in the refueling limit valve is closed or reduced, but refueling continues, it will cause the pressure in the fuel tank to rise sharply, and the liquid level on the side of the refueling pipe will also rise sharply, causing the refueling gun to jump.

[0071] See also Figure 3 During the refueling process, when the fuel level rises to the position of the ventilation window, the fuel will instantly enter the valve core. At this time, the overall gravity of the single float valve core assembly (large float section 3 and small float section 4) and the sealing assembly may be less than the buoyancy of the fuel + the elastic force of the spring 14. Therefore, the single float valve core assembly will drive the sealing assembly to move upward until the sealing assembly hits the top surface of the valve core accommodating cavity. The large sealing ring 11 and the middle sealing ring 12 on the sealing assembly will close the first exhaust port 9, so that the large exhaust channel of the combination valve will be closed, which will cause the pressure in the fuel tank to rise sharply, and then form a refueling gun jump.

[0072] At this time, due to the design of the single float, the top surface of the small float section 4 is attached to the small sealing ring 13 of the sealing assembly, that is, the connecting channel 8 and the second discharge port 10 are closed. When refueling, the oil rises to the closing height, and the single float valve core assembly is subjected to the large buoyancy of the oil. The single float valve core assembly and the sealing assembly are simultaneously pushed upward, and the internal part increases instantly to reach the oil gun jump gun condition. After the gun jumps, the oil inside and outside the valve core gradually balances, and the gravity of the large float section 3 and the small float section 4 will be slightly greater than the buoyancy of the spring 14 force to add oil liquid, and due to the small area of ​​the connecting channel 8 and the setting of the movable part 18, the place has a good opening performance under high pressure environment, so that the large float section 3 and the small float section 4 will move downward until the gravity is equal to the buoyancy of the spring 14 force to add oil liquid.

[0073] 3. The ventilation channel of the refueling limit valve in the combination valve is closed, and the pressure in the fuel tank is released through the flip valve to realize the function of the flip valve. Figure 4This situation usually occurs when the fuel tank is full or some vehicles are at a certain tilt angle, causing the single float valve core assembly and the sealing assembly inside the valve body to rise, closing the large ventilation flow channel. However, due to the large overall difference after the gravity of the single float valve core assembly + movable part 18 minus the elastic force of the spring 14, there is also a large downward gravity, so the single float valve core assembly and the movable part 18 do not rise as a whole. At this time, the small hole (connecting channel 8) under the sealing assembly is still open, but because a pressure-maintaining part is provided above the second discharge port 10, the combined valve as a whole is still in a relatively sealed state. At this time, since the fuel inside the fuel tank will continue to evaporate or be affected by the increase in temperature, the pressure inside the fuel tank will continue to increase. At this time, the function of the flip valve is required to promptly relieve the increased pressure inside the fuel tank. See. Figure 5 When the pressure inside the fuel tank rises to a level high enough to blow up the pressure-maintaining cover 17, the pressure inside the fuel tank will decrease, and the airflow will enter the valve through the small exhaust channel on the side of the base, and then pass through the connecting channel 8 on the sealing assembly to the second exhaust port 10, and then pass through the exhaust channel designed in the pressure-maintaining cover 17 and the pressure-maintaining shell 16, and then be discharged through the pipe mouth.

[0074] 4. When the vehicle is driving, it may shake violently or tilt at a certain angle, and the oil in the fuel tank will also shake violently. At this time, all the exhaust channels inside the combination valve need to be sealed in time to prevent the oil in the fuel tank from leaking out through the vent holes inside the combination valve. Figure 6 The single float valve core assembly and the sealing assembly inside the combination valve will rise in time with the shaking to close the large ventilation flow channel (first discharge port 9) on the valve body, and then the single float valve core assembly and the movable part 18 will also rise in time to close the corresponding small hole flow channel (communication channel 8) under the sealing assembly. In this way, the entire valve core will form a sealed state to prevent fuel leakage (dynamic leakage).

[0075] 5. See Figure 7 In the above four, during the fuel sloshing process, the valve core can be closed in time to prevent dynamic fuel leakage. At the same time, after the valve core is closed in time, the valve core needs to be not only closed in time during the fuel sloshing process, but also needs to be opened in time, because when the valve core is closed in time, the inside of the fuel tank will be in a completely closed state, so the internal pressure will increase accordingly. At this time, the flip valve inside the valve core needs to be opened in time to relieve the pressure inside the fuel tank.

[0076] From P=F / S, it can be known that when F is constant, the larger the contact area S is, the smaller P is. Since the contact area S between the float inside the valve core and the large hole corresponding to the sealing component is relatively large, when there is a certain pressure inside the fuel tank, it is difficult for the large ventilation flow channel to open in time to release the pressure. Therefore, at this time, the small hole (communication channel 8) corresponding to the internal single float valve core component and the movable part 18 needs to be opened in time to release the pressure.

[0077] The refueling limit valve and the rollover valve of the present embodiment both have a theoretical closing height, that is, when the liquid level inside the fuel tank rises to a certain height, the floats inside the refueling limit valve and the rollover valve will rise until the exhaust passage is closed. However, when the liquid level rises to the point where the exhaust passage of the refueling limit valve is closed, it is necessary to ensure that the rollover valve will not close, because at this time the exhaust passage of the rollover valve is needed to relieve the pressure in the fuel tank. Therefore, the closing height of the rollover valve generally needs to be designed to be relatively high to ensure that the rollover valve is still in an open state after the refueling limit valve is closed.

[0078] The following is a supplementary explanation of the implementation principle of the single-float combination valve of this embodiment: when refueling, when the oil rises to reach the closing height, the oil flows into the valve core accommodating chamber, the oil level inside the valve core accommodating chamber is higher than the oil level in the tank, the float is subjected to the larger buoyancy of the oil, and the float and the sealing assembly are simultaneously pushed upward to close the large discharge port and the small discharge port. The interior of the oil tank instantly increases to reach the condition of the oil gun jumping. After the oil inside and outside the valve core accommodating chamber is balanced, the gravity of the float is slightly greater than the buoyancy of the refueling liquid due to the spring force, so that the float will move downward until the gravity of the float is equal to the buoyancy of the refueling liquid due to the spring force, at which time the connecting channel 8 on the sealing assembly is opened to perform the function of exhausting.

[0079] The embodiments of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above embodiments. Even if various changes are made to the present invention, if these changes fall within the scope of the claims of the present invention and their equivalents, they still fall within the protection scope of the present invention.

Claims

1. A combination valve, characterized in that: It includes a valve body, a valve core part and a pressure-maintaining part; The valve body is provided with a valve core accommodating cavity, the valve body is provided with at least one inflow channel communicating with the valve core accommodating cavity, and the upper end of the valve body is provided with a first discharge port and a second discharge port communicating with the valve core accommodating cavity; The valve core part includes a single-float valve core assembly and a sealing assembly; the single-float valve core assembly includes a small float section and a large float section connected to each other, the small float section is located above the large float section, and the large float section is slidably connected to the valve core accommodating chamber; the sealing assembly is slidably connected to the valve core accommodating chamber and is located above the single-float valve core assembly, and is used to cooperate with the large float section and / or the small float section to switch the first discharge port; the sealing assembly is also provided with a connecting channel for connecting the second discharge port and the inflow channel, and is used to cooperate with the small float section to switch the second discharge port, and the connecting channel is smaller than the first discharge port; The pressure-maintaining portion is disposed on the top surface of the valve body, and an input end thereof is communicated with the second discharge port, and is used to limit the pressure required to discharge the fluid from the second discharge port; Wherein, at least one downwardly extending lap joint is arranged on the sealing assembly, and the lap joint end of the downwardly extending lap joint is located outside the small float section in the horizontal direction; and an lap joint matching piece matching the lap joint end of the downwardly extending lap joint is arranged on the upper part of the small float section.

2. The combination valve according to claim 1, characterized in that: The single-float valve core assembly also includes a movable part, which is rotatably connected to the top surface of the small float section and is used to open and close the communication channel.

3. The combination valve according to claim 1, characterized in that: The single-float valve core assembly further comprises an elastic member, a first end of the elastic member is connected to the valve body, and a second end of the elastic member is connected to the small float section and / or the large float section.

4. The combination valve according to claim 1, characterized in that: The sealing assembly includes a sliding member and a sealing member; The sliding member is slidably connected to the valve core accommodating chamber, and the sealing member is installed on the sliding member; the sealing member is provided with the communicating channel and a sealing block for sealing the first discharge port; The sliding member is driven by the single float valve core assembly to slide up and down, and cooperates with the sealing block to open and close the first discharge outlet; the connecting channel connected to the second discharge outlet is used to cooperate with the single float valve core assembly to open and close the second discharge outlet.

5. The combination valve according to claim 4, characterized in that: The sealing block includes a large sealing ring, a middle sealing ring and a small sealing ring; the large sealing ring and the middle sealing ring are both arranged on the upper surface of the sealing member and correspond to the first discharge port; the large sealing ring is sleeved on the first discharge port; the middle sealing ring is located between the first discharge port and the second discharge port; the small sealing ring is arranged on the lower surface of the sealing member, and the small sealing ring is communicated with the middle sealing ring to cooperate to form the communicating channel.

6. The combination valve according to claim 1, characterized in that: The downwardly extending overlapping piece includes a vertically extending piece and a lateral overlapping protrusion; The upper end of the vertical extension piece is connected to the sealing assembly, and the lower end of the vertical extension piece is located away from the small float section; the lateral overlapping protrusion is arranged at the lower end of the vertical extension piece and is arranged toward the small float section.

7. The combination valve according to claim 6, characterized in that: The overlapping matching piece is a lateral annular protrusion arranged around the small float section.

8. The combination valve according to claim 1, characterized in that: The pressure-maintaining part includes a pressure-maintaining shell and a pressure-maintaining cover; a accommodating space is provided in the pressure-maintaining shell, and an inlet hole and a discharge hole connected to the accommodating space are also provided on the pressure-maintaining shell; the pressure-maintaining shell is arranged on the top surface of the valve body, and the inlet hole is connected to the second discharge port; the pressure-maintaining cover is slidably connected to the accommodating space and is used to open and close the inlet hole.

9. The combination valve according to claim 1, characterized in that: It also includes a connecting flange; the connecting flange is connected to the valve body and cooperates with the top surface of the valve body to form a fluid discharge chamber for guiding the fluid discharged from the first discharge port and the pressure maintaining part.

10. The combination valve according to claim 1, characterized in that: The valve body comprises an outer shell with an upward opening and a transfer shell with a downward opening; the outer shell is sleeved on the lower end of the transfer shell and is fixedly connected to the transfer shell; The inner wall surface of the adapter shell cooperates with the bottom surface of the outer shell to form the valve core accommodating chamber; at least one first connecting port is opened on the shell of the outer shell, and the first connecting port, the outer wall surface of the adapter shell and the inner wall surface of the outer shell cooperate to form an inflow channel connected to the valve core accommodating chamber.

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