Quick-response fuel oil return heating structure

Abstract

The invention relates to a quick-response fuel oil return heating structure which comprises a filter seat and a fuel oil return heating assembly, the fuel oil return heating assembly comprises a shell, one side of the shell is provided with a first connector, the other side of the shell is provided with a second connector and a third connector, and the top of the shell is provided with a second control valve assembly. The second control valve assembly comprises a second control valve and a third control valve, the second control valve is used for controlling and connecting the second interface and the third interface, the third control valve is used for controlling and connecting the second interface and the first interface, and the first control valve assembly is used for controlling and connecting the first interface and the connecting part of the filter element cavity. An additional external power supply is not needed, and compared with the external power supply, the SMA spring adjusts a high-temperature fuel oil loop path according to the temperature of surrounding fuel oil, response lag is removed, and the problem that an engine cannot be started or a fuel oil system is damaged is solved.

Description

Technical Field

[0001] The invention relates to the technical field of automobile fuel, and in particular to a fast-response fuel return heating structure. Background Art

[0002] With the implementation of the National VI and above emission standards, engine and vehicle manufacturers have increasingly stringent requirements for engine lightweighting, fuel consumption reduction, high reliability, highly integrated modules and low cost. Engines require lower fuel consumption, lighter weight, more reliable performance, high integration and lower cost. The common heating method on the market is to arrange a heater with an internal resistance wire at the bottom of the fuel filter, which generally has an internal thermostat. Or a PTC ceramic heater arranged between the filter seat and the filter element, most of which also have an internal thermostat.

[0003] However, the inventors found that these two heating methods have the following problems: first, they both require an external power supply, consume a lot of power and take a very long time to heat; second, there is a delay between turning the heating on and off; finally, the thermostat is easily damaged. Once damaged, the heater will continue to heat, which may drain the battery and cause the engine to fail to start, or even damage the fuel system and cause serious consequences.

[0004] Therefore, the present application provides a technical solution for the fuel return system with low energy consumption and the ability to quickly and accurately respond to different engine requirements to solve the problems of high energy consumption, delayed response and fuel system damage in the prior art. Summary of the invention

[0005] The purpose of this section is to summarize some aspects of embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the specification abstract and the invention title of this application to avoid blurring the purpose of this section, the specification abstract and the invention title, and such simplifications or omissions cannot be used to limit the scope of the present invention.

[0006] The present invention is proposed in view of the above-mentioned problems.

[0007] The present application provides a technical solution for a fuel return system with low energy consumption and the ability to quickly and accurately respond to different engine requirements, so as to solve the problems of high energy consumption, delayed response and fuel system damage in the prior art.

[0008] In order to solve the above technical problems, the present invention is solved by the following technical solutions:

[0009] A fast-response fuel return heating structure comprises a filter seat and a fuel return heating assembly installed at a connection portion between the filter seat and a filter element cavity, the fuel return heating assembly comprising a shell, one side of the shell is provided with a first interface connected to a connection portion of the filter element cavity, a first control valve assembly is provided between the first interface and the connection portion of the filter element cavity, the other side of the shell is provided with a second interface for fuel return of a high-pressure oil pipe and a third interface for outputting fuel to a fuel tank, a second control valve assembly is also provided at the top of the shell, the second control valve assembly comprises a second control valve and a third control valve, the second control valve is used to control the connection between the second interface and the third interface, the third control valve is used to control the connection between the second interface and the first interface, the first control valve assembly is used to control the connection between the first interface and the filter element cavity, the first control valve assembly comprises a valve seat, a valve body, a first elastic member provided between the valve seat and the valve body, and a second elastic member provided between the valve body and the connection portion of the filter element cavity on one side of the shell.

[0010] As a preferred solution of the fast-response fuel return heating structure described in the present invention, the valve seat includes a valve cover and an annular wall arranged perpendicular to the valve cover, a valve column extends from the valve body on one side close to the valve seat, the valve column is connected to the valve cover, and the first elastic member is located between the annular wall and the valve column.

[0011] As a preferred solution of the fast-response fuel return heating structure described in the present invention, a first annular boss and a second annular boss are sequentially arranged on the side of the valve body away from the valve seat, the cross-sectional area of ​​the first annular boss is larger than the cross-sectional area of ​​the second annular boss, and the second elastic member is located between the second annular boss and the first interface.

[0012] As a preferred solution of the fast-response fuel return heating structure described in the present invention, an abutting portion abutting against the second annular boss is further provided inside the first interface of the shell.

[0013] As a preferred solution of the fast-response fuel return heating structure described in the present invention, a cover plate for sealing the second control valve and the third control valve is provided on the top of the shell, the second control valve includes a circulation cavity and a spherical valve body disposed in the circulation cavity, the circulation cavity includes a first cavity and a second cavity, the diameter of the spherical valve body is smaller than the diameter of the first cavity and larger than the diameter of the second cavity, the first cavity is connected to the third interface, and the second cavity is connected to the second interface.

[0014] As a preferred solution of the fast-response fuel return heating structure described in the present invention, the third control valve includes a circulation cavity 2 and a spherical valve body 2 disposed in the circulation cavity, the circulation cavity 2 includes a third cavity and a fourth cavity, the diameter of the spherical valve body 2 is smaller than the diameter of the third cavity and larger than the diameter of the fourth cavity, and a circulation hole is provided on the side wall of the fourth cavity to connect with the first interface.

[0015] As a preferred solution of the fast-response fuel return heating structure of the present invention, the first elastic member is an SMA spring, and the SMA spring stretches when the temperature exceeds 20°C.

[0016] As a preferred solution of the fast-response fuel return heating structure of the present invention, the SMA spring retracts when the temperature is below 7°C.

[0017] As a preferred solution of the fast-response fuel return heating structure described in the present invention, the shell is also connected to the filter seat by fixing bolts.

[0018] Beneficial effects of the present invention: The fast-response fuel return heating structure provided by the present application does not require an additional external power supply, and compared with the external power supply method, the SMA spring of the present application can more accurately adjust the high-temperature fuel circuit path according to the ambient fuel temperature, eliminating the problem of response lag, thereby eliminating the problem of the engine failing to start or the fuel system being damaged. In addition, the shell of the fuel return heating assembly in the present application can be a plastic part integrated on the fuel filter, meeting the requirements of high integration and lightweight. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. Among them:

[0020] Figure 1 This is a structural schematic diagram of a fast-response fuel return heating structure described in an embodiment of the present application;

[0021] Figure 2 This is a structural schematic diagram of an exploded view of a fuel return heating assembly according to an embodiment of the present application;

[0022] Figure 3 Based on Figure 1 BB is a schematic diagram of the cross-sectional structure of the embodiment of the present application;

[0023] Figure 4 This is a schematic diagram of the temperature-expansion rate of the first elastic member described in an embodiment of the present application.

[0024] The parts indicated by the numbers in the accompanying drawings are as follows:

[0025] 100-fast response fuel return heating structure; 1-filter seat; 11-connection part of filter element cavity; 2-fuel return heating assembly 2; 21-housing; 212-first interface; 2121-top; 213-second interface; 214-third interface; 215-cover plate; 3-first control valve assembly; 31-valve seat; 311-valve cover; 312-annular wall; 32-valve body; 321-valve column; 322-first annular boss; 323-third Two annular bosses; 33-first elastic member; 34-second elastic member; 35-bolt; 36-metal insert; 4-second control valve assembly; 41-second control valve; 411-circulation cavity one; 4111-first cavity; 4112-second cavity; 412-spherical valve body one; 42-third control valve; 421-circulation cavity two; 4211-third cavity; 4212-fourth cavity; 42121-circulation hole; 422-spherical valve body two. DETAILED DESCRIPTION

[0026] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in the art without creative work should fall within the scope of protection of the present invention.

[0027] like Figures 1 to 2 As shown, the present invention provides a fast-response fuel return heating structure 100, comprising a filter seat 1 and a fuel return heating assembly 2 installed at a connection portion 11 of the filter seat 1 and connected to the filter element cavity, the fuel return heating assembly 2 comprising a housing 21, one side of the housing 21 is provided with a first interface 212 connected to the connection portion 11 of the filter element cavity, a first control valve assembly 3 is provided between the first interface 212 and the connection portion 11 of the filter element cavity, the other side of the housing 21 is provided with a second interface 213 for high-pressure fuel pipe fuel return and a third interface 2114 for outputting fuel to a fuel tank, and the top of the housing 21 is also provided with a second The control valve 41 assembly 4 includes a second control valve 41 and a third control valve 42. The second control valve 41 is used to control the connection between the second interface 213 and the third interface 2114. The third control valve 42 is used to control the connection between the second interface 213 and the first interface 212. The first control valve assembly 3 is used to control the connection between the first interface 212 and the connection part 11 of the filter element cavity. The first control valve assembly 3 includes a valve seat 31, a valve body 32, a first elastic member 33 arranged between the valve seat 31 and the valve body 32, and a second elastic member 34 arranged between the valve body 32 and the connection part 11 of the filter element cavity on one side of the shell 21.

[0028] Specifically, the fuel return heating assembly 2 is integrated on the body of the filter seat 1. The housing 21 of the fuel return heating assembly 2 includes a first interface 212, a second interface 213 and a third interface 2114. The first interface 212 is connected to the connection portion 11 of the filter element cavity of the filter seat 1 and is controlled by the first control valve assembly 3 to determine whether it is connected. The second interface 213 and the third interface 2114 are used for the return of the fuel in the high-pressure oil pipe and the return of the returned fuel to the oil tank, respectively. A second control valve 41 assembly 4 is also provided on the top of the housing 21, including a second control valve 41 and a third control valve 42. The second control valve 41 is used to control the connection between the second interface 213 and the third interface 2114, and the third control valve 42 is used to control the connection between the second interface 213 and the first interface 212.

[0029] It can be seen that there are two routes for fuel reflux. One is to enable the high-pressure fuel pipe to flow into the second interface 213 through the opening of the second control valve 41 and flow out from the third interface 2114 to the fuel tank. The other is to enable the high-pressure fuel pipe to flow into the second interface 213 through the opening of the third control valve 42 and the first control valve assembly 3 and flow out from the first interface 212 to the connecting part 11 of the filter element cavity.

[0030] Furthermore, the first control valve assembly 3 includes a valve seat 31 , a valve body 32 , a first elastic member 33 disposed between the valve seat 31 and the valve body 32 , and a second elastic member 34 disposed between the valve body 32 and the connecting portion 11 of the filter element cavity on one side of the housing 21 .

[0031] Specifically, the first control valve assembly 3 realizes the opening or closing of the connection portion 11 between the first interface 212 and the filter element cavity through the action between the first elastic member 33 and the second elastic member 34. It should be noted that in the present application, the first elastic member 33 is an SMA spring, and the second elastic member 34 is an ordinary spring. The SMA spring is a shape memory alloy spring, which is made of one of the three alloys of nickel-titanium-based shape memory alloy, copper-based shape memory alloy and iron-based shape memory alloy. In the present application, the preferred SMA spring is preferably a nickel-titanium-based shape memory alloy. Figure 3 As shown, the SMA spring is affected by temperature and can quickly change the length of the spring itself according to different ambient temperatures. It can be seen that the SMA spring will stretch when the temperature is below 7 degrees Celsius and above 20 degrees Celsius. Obviously, ordinary springs stretch when the temperature is low and shorten when the temperature is high.

[0032] Furthermore, the valve seat 31 includes a valve cover 311 and an annular wall 312 arranged perpendicular to the valve cover 311. A valve column 321 extends from the valve body 32 on the side close to the valve seat 31. The valve column 321 is connected to the valve cover 311. The first elastic member 33 is located between the annular wall 312 and the valve column 321. A first annular boss 322 and a second annular boss 323 are sequentially arranged on the side of the valve body 32 away from the valve seat 31. The cross-sectional area of ​​the first annular boss 322 is larger than that of the second annular boss 323. The second elastic member 34 is located between the second annular boss 323 and the first interface 212.

[0033] Specifically, the SMA spring is located between the annular wall 312 of the valve seat 31 and the valve column 321 of the valve body 32 . One end of the ordinary spring contacts the first annular boss 322 , is sleeved on the second annular boss 323 , and the other end is connected to the first interface 212 .

[0034] Furthermore, a butting top portion 2121 which butts against the second annular boss 323 is further provided inside the first interface 212 of the housing 21 .

[0035] Specifically, the first interface 212 is provided with an abutting top portion 2121 connected to the second annular boss 323 . It can be understood that the common spring is sleeved on the abutting top portion 2121 and the second annular boss 323 and is located in the first interface 212 .

[0036] It can be imagined that when the SMA spring is extended, the ordinary spring is compressed by the force, and the second annular boss 323 of the valve body 32 abuts against the abutting top 2121 of the first interface 212. When the SMA spring is shortened, the ordinary spring is extended, and the second annular boss 323 of the valve body 32 does not abut against the abutting top 2121 of the first interface 212.

[0037] It can be seen that the SMA spring is extended or shortened due to the influence of temperature, thereby changing the shortening or elongation of the ordinary spring, so that the second annular boss 323 of the valve body 32 is in contact with or not in contact with the abutting top portion 2121 in the first shell body 21, and finally the first interface 212 and the connecting portion 11 of the filter element cavity are connected or not connected.

[0038] Furthermore, a cover plate 215 for sealing the second control valve 41 and the third control valve 42 is provided on the top of the shell 21. The second control valve 41 includes a circulation cavity 411 and a spherical valve body 412 disposed in the circulation cavity. The circulation cavity 411 includes a first cavity 4111 and a second cavity 4112. The diameter of the spherical valve body 412 is smaller than the diameter of the first cavity 4111 and larger than the diameter of the second cavity 4112. The first cavity 4111 is connected to the third interface 2114, and the second cavity 4112 is connected to the second interface 213.

[0039] The third control valve 42 includes a circulation cavity 421 and a spherical valve body 42 placed in the circulation cavity. The circulation cavity 421 includes a third cavity 4211 and a fourth cavity 4212. The diameter of the spherical valve body 42 is smaller than the diameter of the third cavity 4211 and larger than the diameter of the fourth cavity 4212. The side wall of the fourth cavity 4212 is provided with a circulation hole 42121 connected to the first interface 212.

[0040] Specifically, the spherical valve body 1 412 and the spherical valve body 2 are respectively connected to the second cavity 4112 and the third cavity 4211 by gravity, and the spherical valve body 1 412 and the spherical valve body 2 can be plastic balls or hollow metal balls. They are lifted up under the influence of different pressures, thereby achieving the communication between the second interface 213 and the third interface 2114 or the communication between the second interface 213 and the first interface 212.

[0041] It should also be noted that the cover plate 215 seals the second control valve 41 and the third control valve 42 at the same time, and the cover plate 215 and the housing 21 may be sealed by welding or by a sealing ring, thereby meeting the airtightness requirement.

[0042] In addition, the position where the side wall of the fourth cavity 4212 engages with the two side walls of the spherical valve body is lower than the position of the flow hole 42121 .

[0043] Furthermore, the housing 21 is also connected to the filter seat 1 by fixing bolts 35. It can be understood that the stability of the fuel return heating assembly 2 is ensured. In addition, in the present application, the housing 21 can also be made of plastic. When the housing 21 is made of plastic, in addition to being connected to the filter seat 1 by bolts 35, a metal insert 36 is also provided at the connection position.

[0044] Furthermore, a sealing ring is sleeved on the first interface 212 of the housing 21 to ensure the sealing between the first interface 212 of the housing 21 and the connecting portion 11 of the filter element cavity of the filter seat 1. The sealing ring is made of fluororubber or fluorosilicone rubber.

[0045] In an actual application scenario provided by the present application, if the ambient temperature is high, such as in summer or after the engine has been running for a period of time, the temperature of the fuel tank and the entire fuel line is high, which is greater than the temperature at which the SMA spring can be deformed and stretched, such as Figure 4As shown, the SMA spring is stretched, the ordinary spring is compressed, the second annular boss 323 of the valve body 32 and the abutting top 2121 in the first interface 212 abut against each other, no air pressure is generated in the first interface 212, no air flows through the flow hole 42121 between the fourth cavity 4212 and the first interface 212, and the spherical valve body 2 is clamped in the fourth cavity 4212 by gravity. The fuel in the high-pressure oil pipe flows into the second interface 213, and when passing through the second control valve 41, the spherical valve body 1 412 is lifted to the first cavity 4111, and then flows back to the fuel tank through the third interface 2114.

[0046] like Figure 4 As shown, if the ambient temperature is low, such as in winter or when the engine has just started to run, the temperature of the fuel tank and the entire fuel pipeline is low, which is lower than the temperature at which the SMA spring deforms and shortens, the SMA spring retracts, the ordinary spring is extended, the second annular boss 323 of the valve body 32 and the abutting top 2121 in the first interface 212 do not abut against each other, the first interface 212 is connected to the connecting portion 11 of the filter element cavity, the flow hole 42121 between the fourth cavity 4212 and the first interface 212 is ventilated and is under negative pressure, the spherical valve body 2 is sucked into the third cavity 4211 under the influence of negative pressure, and similarly, the spherical valve body 1 412 of the second control valve 41 is affected by gravity and negative pressure and is clamped in the second cavity 4112, the fuel refluxed from the high-pressure oil pipe flows into the second interface 213, flows to the first interface 212 through the third control valve 42 and the flow hole 42121, and flows to the filter element cavity through the first interface 212. The high-temperature fuel from the high-pressure fuel pipe is mixed and heated with the low-temperature fuel in the fuel tank inside the filter cavity, and then enters the fuel pump after being filtered.

[0047] That is, it can also be understood that when the ambient temperature around the SMA spring is low, the SMA spring shortens, and the high-temperature fuel enters the fuel filter element cavity through the SMA spring and mixes with the low-temperature fuel from the fuel tank, which can quickly increase the temperature of the fuel inside the fuel filter and improve the fluidity of the fuel. It can also provide sufficient fuel pressure to the suction side of the fuel pump, and can provide the common rail system with high-temperature and stable-pressure fuel to ensure the power and economy of the engine and meet higher emission regulations. When the temperature around the SMA spring is high, the SMA spring extends, and the fuel supply on the suction side of the fuel pump is smooth. There is no need for high-temperature fuel to enter the fuel filter, and the high-temperature fuel returns directly to the fuel tank.

[0048] It can be seen that the present invention can sense the surrounding fuel temperature through the SMA spring without the need for an external power supply, and can more quickly and accurately adjust the high-temperature fuel return path to eliminate the problem of response lag. At the same time, the technical solution of the present application can solve the problem of insufficient power during low-temperature startup and initial operation. For example, at low temperatures, the fuel will wax, the viscosity will increase, the fluidity will deteriorate, the resistance of the entire fuel system is very high, and it is impossible to provide the engine with enough fuel for combustion; after the engine is ignited, due to the poor fluidity of the fuel, the precipitation of air will be aggravated, the engine fuel supply is insufficient, and a large amount of air is mixed in the fuel, which will cause the engine to shake, lack of power, and even stall; due to insufficient fuel supply, the emission requirements of the engine will be affected, and in a low-temperature environment, the emission regulations cannot be met.

[0049] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. A fast-response fuel return heating structure, characterized in that: The invention comprises a filter seat and a fuel return heating assembly installed at a connection part between the filter seat and a filter element cavity, the fuel return heating assembly comprises a shell, a first interface connected to a connection part of the filter element cavity is provided on one side of the shell, a first control valve assembly is provided between the first interface and the connection part of the filter element cavity, a second interface for fuel return of a high-pressure oil pipe and a third interface for outputting fuel to a fuel tank are provided on the other side of the shell, a second control valve assembly is also provided on the top of the shell, the second control valve assembly comprises a second control valve and a third control valve, the second control valve is used to control the connection between the second interface and the third interface, the third control valve is used to control the connection between the second interface and the first interface, the first control valve assembly is used to control the connection between the first interface and the connection part of the filter element cavity, the first control valve assembly comprises a valve seat, a valve body, a first elastic member provided between the valve seat and the valve body, and a second elastic member provided between the valve body and the connection part of the filter element cavity on one side of the shell.

2. The fast-response fuel return heating structure according to claim 1, characterized in that: The valve seat comprises a valve cover and an annular wall arranged perpendicular to the valve cover. A valve column extends from one side of the valve body close to the valve seat. The valve column is connected to the valve cover. The first elastic member is located between the annular wall and the valve column.

3. The fast-response fuel return heating structure according to claim 1, characterized in that: A first annular boss and a second annular boss are sequentially arranged on a side of the valve body away from the valve seat, the cross-sectional area of ​​the first annular boss is larger than the cross-sectional area of ​​the second annular boss, and the second elastic member is located between the second annular boss and the first interface.

4. The fast-response fuel return heating structure according to claim 3, characterized in that: An abutting top portion abutting against the second annular boss is also provided inside the first interface of the shell.

5. The fast-response fuel return heating structure according to claim 1, characterized in that: A cover plate for sealing the second control valve and the third control valve is provided on the top of the shell. The second control valve includes a circulation cavity and a spherical valve body disposed in the circulation cavity. The circulation cavity includes a first cavity and a second cavity. The diameter of the spherical valve body is smaller than the diameter of the first cavity and larger than the diameter of the second cavity. The first cavity is connected to the third interface, and the second cavity is connected to the second interface.

6. The fast-response fuel return heating structure according to claim 5, characterized in that: The third control valve includes a circulation cavity 2 and a spherical valve body 2 placed in the circulation cavity. The circulation cavity 2 includes a third cavity and a fourth cavity. The diameter of the spherical valve body 2 is smaller than the diameter of the third cavity and larger than the diameter of the fourth cavity. A circulation hole is opened on the side wall of the fourth cavity to connect with the first interface.

7. The fast-response fuel return heating structure according to claim 1, characterized in that: The first elastic member is an SMA spring, and the SMA spring stretches when the temperature exceeds 20°C.

8. The fast-response fuel return heating structure according to claim 1, characterized in that: The SMA spring retracts below 7°C.

9. The fast-response fuel return heating structure according to claim 1, characterized in that: The shell is also connected to the filter seat via fixing bolts.

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