Air filter of aircraft fuel system

Abstract

The invention provides an air filter of an aircraft fuel system, and belongs to the field of aircraft fuel systems, the air filter comprises a shell, a slidable joint, a fixed joint and the like, the shell is hermetically mounted at an opening of an aircraft sealing frame, a filter screen mounting groove is formed in one end of the shell, a filter screen is arranged in the groove, one end of the shell is connected with the fixed joint, and the other end of the shell is connected with the slidable joint; the inner wall of the slidable connector is provided with a rectification slope. According to the invention, the occupied space is small, and rapid disassembly and assembly can be realized; the sealing device can be used for sealing frame penetrating positions such as pressure bulkheads; the thread specifications of the interfaces on the two sides can be designed as required, so that variable-diameter switching is realized; one side of the slidable connector can adjust the installation stress of the pipeline system in a self-adaptive mode, the pipeline is protected, and the risk of pipeline breakage is reduced.

Description

Technical Field

[0001] The invention belongs to the field of aviation fuel systems and relates to an air filter of an aircraft fuel system. Background Art

[0002] The air filter is one of the commonly used devices in the aircraft fuel system, which is used to filter impurities in the air and ensure the cleanliness of the aircraft fuel tank. There are two types of commonly used air filters. One type is a larger device, which is equipped with a mounting seat, two inlet and outlet interfaces, and a filter cup. This type of air filter needs to be designed to support and connect with the interface when in use, and occupies a large space. This type of filter is hard-connected to the pipeline, and there is installation stress in the pipeline, which poses a risk of damage. The other type is a single filter, which has a flange structure at one end and is directly stuck at the connection between the pipeline and the pipeline joint (there is no structure to tighten / press it). This type of filter is not stable to install, and the filter will shake when it is vibrated (when air flows through), affecting the filtering effect, and the filter is easy to fall off during disassembly and assembly. Summary of the invention

[0003] The present invention provides an air filter for an aircraft fuel system. The air filter occupies a small space and can be quickly disassembled and assembled through a configuration design. The air filter can be used in a pressure bulkhead or other frame locations where sealing is required. The thread specifications of interfaces on both sides can be designed as required to achieve diameter-changing connection. One side of a slidable joint can adaptively adjust the installation stress of a pipeline system (after changing the configuration of an outer shell, the installation stress of the pipeline system can be adaptively adjusted on both sides), thereby protecting the pipeline and reducing the risk of the pipeline being broken.

[0004] The technical solution adopted by the present invention is as follows:

[0005] An air filter for an aircraft fuel system, the air filter comprising a housing 1, a slidable joint 2, a fixed joint 3, a spring 4, a filter screen 5, a gasket 6, a locking gasket 7, a nut 8, and a sealing ring 9.

[0006] The shell 1 is a long cylindrical part, and its inner hole is a stepped hole. The outer wall of the end with a smaller inner diameter is provided with an external thread and a sealing ring installation groove for installing a sealing ring 9 and sealingly connecting the fixed joint 3. The inner wall of this end is provided with a filter screen installation groove; the middle part of the shell 1 is provided with an external thread for threaded cooperation with the nut 8, a sealing flange is provided on the side away from the fixed joint 3 next to the external thread area, and a sealing ring installation groove is provided on the end surface of the sealing flange facing the external thread, and another sealing ring 9 is installed in the groove. The shell 1 is inserted into the opening of the sealing frame so that the sealing flange fits the sealing frame, and the nut 8 is screwed in from the other side of the sealing frame to press the sealing frame between the nut 8 and the sealing flange. A hexagonal boss is provided on the shell 1 near the other side of the sealing flange, and clamping is achieved by using tools during installation; a boss is provided along the circumference of the inner wall of the end with a larger inner diameter of the shell 1, and a plurality of through-grooves and non-through-grooves are evenly distributed on the boss, which are distributed at intervals and are used to connect the slidable joint 2.

[0007] The slidable joint 2 is a long cylindrical part, and its outer wall is stepped. The outer diameter of its small diameter section matches the inner diameter of the small diameter section of the shell 1, and the outer diameter of the large diameter section matches the inner diameter of the boss on the inner wall of the large diameter section of the shell 1; the inner wall of the small diameter section of the slidable joint 2 is set as a rectifying inclined surface, and the spring 4 is sleeved outside the small diameter section and pressed between the inner wall shoulder of the shell 1 and the outer wall shoulder of the slidable joint 2; the large diameter end of the slidable joint 2 is formed with an external thread for connecting the pipeline, and the other end of the large diameter section is evenly distributed along the circumference with a plurality of mounting bosses, which are connected to the inner wall of the shell 1. The card groove on the wall boss cooperates to achieve a quick fixed connection between the two. The slidable joint 2 is inserted into the outer shell 1, and the mounting boss is pressed into the through card groove and then the slidable joint 2 is rotated. Under the action of the spring 4, the mounting boss is pressed into the non-through card groove. A protruding sealing ring mounting groove is also formed on the large diameter section of the slidable joint 2 for installing another sealing ring 9 to achieve a sealed fit with the inner wall of the large diameter section of the outer shell 1. The part of the large diameter section of the slidable joint 2 located outside the outer shell 1 is formed with a structural plane for easy installation with the cooperation of tools.

[0008] The fixing joint 3 is a cylindrical part, one end of which is formed with an internal thread for connecting with the housing 1, and the inner wall of the side is formed with a locking gasket installation groove, and the other end of the fixing joint 3 is formed with an external thread for connecting the pipeline.

[0009] The filter screen 5 , the gasket 6 , and the anti-loosening gasket 7 are sequentially placed in the filter screen installation groove of the housing 1 , and another anti-loosening gasket 7 is installed in the anti-loosening gasket installation groove in the fixed joint 3 .

[0010] Furthermore, the load output by the spring 4 should be appropriate and not too large.

[0011] Furthermore, the external threads on the fixed joint 3 and the slidable joint 2 are provided with a plurality of different specifications to realize the connection of different pipelines or to realize the change-diameter conversion.

[0012] The air filter assembly process is as follows: the filter 5, gasket 6 and anti-loosening gasket 7 are sequentially installed in the filter installation groove of the shell 1, the sealing ring 9 is respectively installed in the two sealing ring installation grooves of the shell 1, and then another anti-loosening gasket 7 is installed in the anti-loosening gasket installation groove in the fixed joint 3, and the shell 1 and the fixed joint 3 are tightened; the sealing ring 9 is installed in the sealing ring installation groove of the slidable joint 2, the spring 4 is inserted into the small diameter section of the slidable joint 2 and then inserted into the shell 1 together, the installation boss on the slidable joint 2 is pressed into the through-groove and then the slidable joint 2 is rotated, and under the action of the spring 4, the installation boss is pressed into the non-through-groove.

[0013] The beneficial effects of the present invention are:

[0014] 1. The present invention not only meets the functions of traditional air filters, but also adds functions such as quick disassembly and assembly of equipment, quick disassembly and assembly of filter screens, and stress adjustment of pipeline installation, and has high practicality;

[0015] 2. The present invention has a simple structure, is easy to manufacture and assemble, has a simple operation form, is easy to implement, and has high economic benefits;

[0016] 3. The present invention has good versatility, occupies a small space, does not need to be configured with special support, has a small weight, can be used in aircraft fuel systems (auxiliary fuel systems), and has a wide range of applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is an overall schematic diagram of the present invention;

[0018] Figure 2 It is a schematic diagram of each part of the present invention;

[0019] Figure 3 The figures are the external structure diagram and the internal cross-sectional view of the shell, wherein (a) is the external structure diagram of the shell, and (b) is the internal cross-sectional view of the shell;

[0020] Figure 4 It is a slidable joint and an internal cross-sectional view;

[0021] Figure 5 The figures are external structure diagrams and internal cross-sectional diagrams of the fixed joint, wherein (a) is the external structure diagram of the fixed joint, and (b) is the internal cross-sectional diagram of the fixed joint;

[0022] Figure 6 It is a cross-sectional view of the present invention;

[0023] Figure 7 This is a schematic diagram of a housing without a frame-penetrating sealing function;

[0024] In the figure: 1 housing; 2 sliding joint; 3 fixed joint; 4 spring; 5 filter screen; 6 gasket; 7 anti-loosening gasket; 8 nut; 9 sealing ring 9. DETAILED DESCRIPTION

[0025] The technical solution of the present invention is described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. All other embodiments improved or adjusted by ordinary technicians in this field based on the embodiments of the present invention belong to the protection scope of the present invention.

[0026] This embodiment provides an air filter for an aircraft fuel system, the air filter comprising a housing 1, a slidable joint 2, a fixed joint 3, a spring 4, a filter screen 5, a gasket 6, a locking gasket 7, a nut 8, and a sealing ring 9. Figure 1 , Figure 2 and Figure 6 shown.

[0027] like Figure 3 As shown, the shell 1 is a long cylindrical part, and its inner hole is a stepped hole. The outer wall of the end with a smaller inner diameter is formed with an external thread and a sealing ring installation groove for installing a sealing ring 9 and sealingly connecting the fixed joint 3. The inner wall of this end is formed with a filter screen installation groove; the middle part of the shell 1 is formed with an external thread for threaded cooperation with the nut 8, and a sealing flange is provided on the side away from the fixed joint 3 next to the external thread area, and a sealing ring installation groove is formed on the end surface of the sealing flange facing the external thread, and another sealing ring 9 is installed in the groove. The shell 1 is inserted into the opening of the sealing frame to make the sealing flange fit the sealing frame, and the nut 8 is screwed in from the other side of the sealing frame to press the sealing frame between the nut 8 and the sealing flange. A hexagonal boss is provided on the shell 1 near the other side of the sealing flange, and clamping is achieved by using tools during installation; the inner wall of the end with a larger inner diameter of the shell 1 is provided with a boss along the circumference, and a plurality of through-grooves and non-through-grooves are evenly distributed on the boss, which are distributed at intervals and are used to connect the slidable joint 2.

[0028] like Figure 4As shown, the slidable joint 2 is a long cylindrical part, and its outer wall is stepped. The outer diameter of its small diameter section matches the inner diameter of the small diameter section of the shell 1, and the outer diameter of the large diameter section matches the inner diameter of the boss on the inner wall of the large diameter section of the shell 1; the inner wall of the small diameter section of the slidable joint 2 is set as a rectifying inclined surface, and the spring 4 is sleeved outside the small diameter section and pressed between the inner wall shoulder of the shell 1 and the outer wall shoulder of the slidable joint 2; the large diameter end of the slidable joint 2 is formed with an external thread for connecting the pipeline, and the other end of the large diameter section is evenly distributed along the circumference with a plurality of mounting bosses, which are connected to the shell 1, the card groove on the inner wall boss cooperates to realize the quick fixed connection between the two, the slidable joint 2 is inserted into the shell 1, the mounting boss is pressed into the through card groove and then the slidable joint 2 is rotated, and under the action of the spring 4, the mounting boss is pressed into the non-through card groove, and a protruding sealing ring mounting groove is also formed on the large diameter section of the slidable joint 2 for installing another sealing ring 9 to achieve sealing cooperation with the inner wall of the large diameter section of the shell 1, and a structural plane is formed on the part of the large diameter section of the slidable joint 2 located outside the shell 1 for easy installation with the matching tool.

[0029] like Figure 5 As shown, the fixing joint 3 is a cylindrical part, one end of which is formed with an internal thread for connecting to the housing 1, the inner wall of which is formed with an anti-loosening gasket installation groove, and the other end of the fixing joint 3 is formed with an external thread for connecting the pipeline.

[0030] The filter screen 5 , the gasket 6 , and the anti-loosening gasket 7 are sequentially placed in the filter screen installation groove of the housing 1 , and another anti-loosening gasket 7 is installed in the anti-loosening gasket installation groove in the fixed joint 3 .

[0031] The air filter assembly process is as follows: the filter 5, gasket 6 and anti-loosening gasket 7 are sequentially installed in the filter installation groove of the shell 1, the sealing ring 9 is respectively installed in the two sealing ring installation grooves of the shell 1, and then another anti-loosening gasket 7 is installed in the anti-loosening gasket installation groove in the fixed joint 3, and the shell 1 and the fixed joint 3 are tightened; the sealing ring 9 is installed in the sealing ring installation groove of the slidable joint 2, the spring 4 is inserted into the small diameter section of the slidable joint 2 and then inserted into the shell 1 together, the installation boss on the slidable joint 2 is pressed into the through-groove and then the slidable joint 2 is rotated, and under the action of the spring 4, the installation boss is pressed into the non-through-groove.

[0032] The installation process of the air filter is as follows: pass one end of the fixed joint 3 of the air filter through the opening of the sealing frame, use a tool to clamp the hexagonal boss of the housing 1 until the sealing flange fits the sealing frame, and tighten the nut 8 on the other side of the sealing frame; continue to use the tool to clamp the hexagonal boss of the housing 1 to complete the pipe installation on the side of the slidable joint 2; then use the tool to clamp the structural plane outside the fixed joint 2 to complete the pipe installation on the side of the fixed joint 3. The disassembly process is the reverse operation of the above.

[0033] The filter replacement process is as follows: after removing the air filter, remove the fixing joint 3 from the outer shell 1, take down the anti-loosening gasket 7, gasket 6 and filter 5 in the filter installation groove of the outer shell 1, and then install the new filter 5, gasket 6 (replace as needed), and anti-loosening gasket 7 (replace as needed) into the outer shell 1 in sequence, and then connect the fixing joint 3 to the outer shell 1 to complete the filter replacement.

[0034] In other embodiments, the air filter does not need to pass through the sealing frame and is only used to realize the double-sided adaptive adjustment of the installation stress of the pipeline system. Then, the structure of the air filter is improved by removing the external thread and the sealing flange in the middle of the housing 1 and removing the nut 8. Figure 7 shown.

[0035] The above-described embodiments merely express the implementation methods of the present invention, but they should not be understood as limiting the scope of the present invention. It should be pointed out that for those skilled in the art, several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. An air filter for an aircraft fuel system, characterized in that: The air filter comprises a housing (1), a slidable joint (2), a fixed joint (3), and a filter screen (5); The middle part of the shell (1) is sealed and connected to the opening of the sealing frame, and one end thereof is detachably sealed and connected to the fixed joint (3). The inner wall of the end is provided with a filter screen installation groove, in which a filter screen (5) is arranged. The other end of the shell (1) is detachably sealed and connected to the slidable joint (2).

2. An air filter for an aircraft fuel system according to claim 1, characterized in that: The specific structure of the air filter is: The shell (1) is a long cylindrical part, and its inner hole is a stepped hole. The outer wall of the end with a smaller inner diameter is provided with an external thread and a sealing ring installation groove for installing a sealing ring (9) and sealingly connecting the fixed joint (3). The inner wall of this end is provided with a filter screen installation groove, and the filter screen (5), a gasket (6) and a locking gasket (7) are placed in the groove in sequence; the middle part of the shell (1) is provided with an external thread for threading with a nut (8), and a sealing flange is provided on the side of the external thread area away from the fixed joint (3), and a sealing ring installation groove is provided on the end surface of the sealing flange facing the external thread, and another sealing ring (9) is installed in the groove. The shell (1) is inserted into the opening of the sealing frame, and the nut (8) is screwed into the sealing frame from the other side, so that the sealing frame is pressed between the nut (8) and the sealing flange; the inner wall of the end with a larger inner diameter of the shell (1) is provided with a boss along the circumference, and a plurality of through-grooves and non-through-grooves are evenly distributed on the boss, and the two are distributed at intervals, and are used to connect the slidable joint (2); The slidable joint (2) is a long cylindrical part, and its outer wall is stepped. The outer diameter of its small diameter section matches the inner diameter of the small diameter section of the shell (1), and the outer diameter of the large diameter section matches the inner diameter of the boss on the inner wall of the large diameter section of the shell (1); the inner wall of the small diameter section of the slidable joint (2) is set as a rectifying inclined surface, and the spring 4 is sleeved outside the small diameter section and pressed between the inner wall shoulder of the shell (1) and the outer wall shoulder of the slidable joint (2); the large diameter end of the slidable joint (2) is provided with an external thread for connecting the pipeline, and the other end of the large diameter section is provided with a plurality of mounting bosses evenly distributed along the circumference, which cooperate with the card groove on the inner wall boss of the shell (1) to realize the quick fixed connection between the two, and the large diameter section of the slidable joint (2) is also provided with a protruding sealing ring mounting groove for installing another sealing ring (9) to achieve sealing cooperation with the inner wall of the large diameter section of the shell (1); The fixing joint (3) is a cylindrical part, one end of which is provided with an internal thread for connecting to the housing (1), the inner wall of which is provided with an anti-loosening washer installation groove, in which another anti-loosening washer (7) is installed, and the other end of the fixing joint (3) is provided with an external thread for connecting to a pipeline.

3. The air filter of an aircraft fuel system according to claim 1, characterized in that: The inner wall of the small diameter section of the slidable joint (2) is arranged as a rectifying inclined surface.

4. The air filter of an aircraft fuel system according to claim 1, characterized in that: A hexagonal boss is provided on one side of the sealing flange on the housing (1) close to the fixed joint (3), and a structural plane is provided on the part of the large diameter section of the slidable joint (2) located outside the housing (1) for clamping during installation.

5. The air filter of an aircraft fuel system according to claim 1, characterized in that: The external threads on the fixed joint (3) and the slidable joint (2) are provided with a variety of different specifications to achieve connection of different pipelines or diameter-changing switching.

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