Filter with filter element neglected loading prevention function

Abstract

The utility model discloses a filter with a function of preventing neglected loading of a filter element, which comprises a pressure difference indicator, a filter shell, a filter element assembly and a valve assembly which are coaxially assembled, and a first sealing ring serving as a radial sealing structure is arranged between the pressure difference indicator and the filter element assembly; a second sealing ring serving as a radial sealing structure is arranged between the valve assembly and the filter element assembly, and the pressure difference indicator is assembled at the first axial end of the filter shell through an elastic check ring for a shaft. The differential pressure indicator is mainly composed of an indicator shell, a temperature sensor assembly, a signal cap assembly, a magnetic steel assembly, a sleeve and a large spring. The indicator shell and the large spring are of an assembled and movable structure in the sleeve main body of the pressure difference indicator, and the large spring with a certain pre-deformation amount is set to achieve the neglected loading prompting function of the filter element assembly. The valve assembly is located at the outlet of the filter shell and provided with a normal channel and a bypass channel. The device is suitable for accessories of an aviation fuel system and a lubricating oil system, has the bypass valve and filter element neglected loading prompting function, and can achieve the function of stably filtering oil liquid.

Description

TECHNICAL FIELD

[0001] The utility model relates to a filter with filter core leakproof loading function belongs to filter technical field. BACKGROUND

[0002] In the working process of aviation fuel system, oil system, system working oil liquid inevitably contains various impurities, and the impurities will cause damage to the system. In order to ensure the normal operation of the system, reduce the wear of the components in the system and prolong the service life, the filter is arranged in the system accessories to filter the impurities in the working oil. According to the use function of the filter, the filter is provided with a bypass valve and a self-sealing valve. The bypass valve is used to ensure the normal oil supply of the system when the filter core is blocked. The self-sealing valve is used to automatically close the inlet channel of the filter when the filter core is replaced, so as to prevent foreign matters from entering and prevent the system oil from leaking. In the maintenance process of the filter, the filter core may be missing. In order to avoid the missing of the filter core and the damage of the impurities to the system, the filter and the differential pressure indicator need to be optimized in structure to realize the filter core leakproof loading function. SUMMARY

[0003] The utility model aims at providing a filter with filter core leakproof loading function, which is suitable for aviation fuel system, oil system accessories, and has a bypass valve and filter core missing prompt function, and has the function of realizing stable filtration of oil.

[0004] To achieve the above purpose, the utility model adopts the following technical scheme:

[0005] A filter with filter core leakproof loading function comprises a differential pressure indicator, a filter housing, a filter core assembly and a valve assembly which are coaxially assembled, wherein:

[0006] The filter core assembly comprises a radial liquid inlet and an axial liquid outlet, and the filter core assembly is installed in the inner cavity of the filter housing.

[0007] The differential pressure indicator is connected to the axial first end of the filter core assembly through the axial first end of the filter housing, the high-pressure cavity of the differential pressure indicator is located outside the filter core assembly and communicates with the inner cavity of the filter housing, and the low-pressure cavity of the differential pressure indicator is located inside the filter core of the filter core assembly.

[0008] The differential pressure indicator mainly consists of an indicator housing, a temperature sensor assembly, a signal cap assembly, a magnetic steel assembly, a sleeve and a large spring, wherein the differential pressure indicator is connected with the axial first end of the filter element assembly through the sleeve, the indicator housing is slidingly connected in the sleeve, the large spring is located in the sleeve and the two ends thereof are tightly attached to the axial second end of the indicator housing and the inner wall of the sleeve respectively, the signal cap assembly contains a ring magnet and is slidingly connected inside the axial first end of the indicator housing, the temperature sensor assembly is fixed inside the axial first end of the indicator housing and contains a temperature-sensitive memory metal sheet, the free end of the temperature-sensitive memory metal sheet points to the signal cap assembly, the magnetic steel assembly is slidingly connected inside the indicator housing, the axial first end of the magnetic steel assembly is provided with a magnet with an outer diameter smaller than the inner diameter of the aforementioned ring magnet, and a piston is further provided on the magnetic steel assembly, which separates the inside of the indicator housing into a high-pressure cavity and a low-pressure cavity, and the axial second end of the magnetic steel assembly extends to the outside of the sleeve.

[0009] The valve assembly is connected with the axial second end of the filter element assembly through the axial second end of the filter housing, and there is an annular gap between the valve assembly and the filter housing to form a fuel inlet channel, the valve assembly is provided with a fuel bypass valve inlet on the end face outside the filter housing, and the valve assembly further contains a valve for sealing the bypass valve inlet driven by a spring.

[0010] Further,

[0011] The differential pressure indicator and the filter element assembly contain a first sealing ring as a radial sealing structure.

[0012] The valve assembly and the filter element assembly contain a second sealing ring as a radial sealing structure.

[0013] Further, the differential pressure indicator is assembled at the axial first end of the filter housing through an elastic retaining ring for the shaft.

[0014] Further,

[0015] The indicator housing is further provided with a reset channel, the reset channel contains at least two cavities with different inner diameters, and the signal cap assembly is slidingly connected outside the reset channel.

[0016] The differential pressure indicator further comprises a conical spring and a ball, and the conical spring and the ball are assembled in the cavity with the smallest inner diameter in the reset channel.

[0017] Further, the signal cap assembly contains a cap body and an indicating cap, the cap body is tubular, the indicating cap is fixed on the end face of the axial first end of the cap body and located in the cavity with the largest inner diameter in the reset channel, an annular magnet is embedded in the axial second end of the cap body, and the signal cap assembly is slidingly connected outside the reset channel through the cap body.

[0018] Further, the indicator housing is also provided with a blocking ring and a small spring, the blocking ring is installed in the low pressure cavity of the indicator housing through screw thread, and the small spring is located in the low pressure cavity and tightly contacts the piston and the blocking ring at both ends.

[0019] Further, the magnetic steel assembly is installed with a locking nut on the axial second end outside the sleeve.

[0020] Further, the valve assembly comprises a shell, a valve seat and a valve, the shell is installed on the axial second end of the filter element assembly, the end surface of the shell is provided with a fuel bypass valve inlet, the valve seat is a hollow structure and extends through the shell to the filter element of the filter element assembly, the axial first end of the valve seat is a fuel first inlet, the axial second end is a fuel outlet, the circumferential surface of the valve seat is provided with a fuel second inlet, and the valve is slidably connected to the outer surface of the valve seat through a spring.

[0021] The utility model mainly comprises temperature sensor assembly, signal cap assembly, pagoda spring, shell, magnetic steel assembly, sleeve, big spring and locking nut etc. The main role of temperature sensor assembly is to lock or release signal cap assembly at the specified temperature value, and realize the temperature locking function of the product. Signal cap assembly cooperates with built-in magnetic steel and magnetic steel assembly, generates an action force of locking signal cap or ejecting signal cap, gives visual alarm indication, and realizes the indication cap locking function of the product through internal pagoda spring and ball. Magnetic steel assembly forms high and low pressure cavities in the indicator housing through sealing ring, so that the filter cooperates with signal cap assembly to give visual alarm indication when reaching the specified pressure difference value, and realizes the indication pressure difference function of the filter. Big spring pushes the components in the indicator housing, and the action force between magnetic steel assembly and signal cap assembly makes the indication cap in the trend of ejection, so as to realize the filter element anti-leakage installation function of the filter.

[0022] Temperature sensor assembly and signal cap assembly are gap cooperation, signal cap assembly can slide in the axial direction of temperature sensor assembly, and is affected by temperature sensing memory metal sheet on temperature sensor assembly, and the temperature sensing memory metal sheet is in the locking state (signal cap assembly is limited, cannot slide in the axial direction, and cannot generate alarm) under low temperature condition. Pagoda spring and ball in the indicator housing realize the horizontal locking function of signal cap assembly, realize the locking function of signal cap assembly, control the locking of pressure difference indicator in the horizontal state, and realize the reset in the vertical state. Pressure difference indicator is fixed on the filter housing and belongs to the fixed state. Magnetic steel assembly realizes axial displacement under the action of high and low pressure cavities and spring cooperation. Indicator housing and sleeve are mainly used for the mutual connection of internal components, realize the fixation with filter cup in filter element assembly and the connection of filter element, big spring pushes the components in the indicator housing, the action force between magnetic steel assembly and signal cap assembly makes the indication cap in the trend of ejection, and realizes the filter element anti-leakage installation function.

[0023] Compared with the prior art, this utility model designs a filter structure with filter element anti-leakage function and bypass function. It realizes the function of alarming by differential pressure indicator when the filter element is missing, thereby realizing the leakage detection function, preventing unnecessary failure of the system caused by the missing filter element assembly, and improving the reliability of the system. On the other hand, the valve assembly realizes the fuel bypass function when the filter element assembly is blocked. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the filter structure of this utility model;

[0025] Figure 2 This is a schematic diagram of the media flow direction when the filter of this utility model is working normally. The arrows in the diagram indicate the media flow direction.

[0026] Figure 3 This is an exploded view of the filter assembly of this utility model;

[0027] In the diagram: 1-shaft elastic retaining ring, 2-differential pressure indicator, 3-filter housing, 4-first sealing ring, 5-filter element assembly, 6-second sealing ring, 7-valve assembly;

[0028] Figure 4 This is a structural diagram of the differential pressure indicator of this utility model;

[0029] Figure 5 This is a schematic diagram of the path through which the medium flows via the bypass valve in the valve assembly when the filter element assembly becomes clogged. The arrows in the diagram indicate the direction of medium flow.

[0030] In the diagram: 8-Temperature sensor assembly, 9-Signal cap assembly, 10-Magnet assembly, 11-Sleeve, 12-Large spring, 13-Locking nut, 14-Pagoda spring, 15-Indicator housing, 16-Temperature memory metal sheet. Detailed Implementation

[0031] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. However, it should not be construed that the scope of the subject matter of the present invention is limited to the following embodiments. Any modifications, substitutions and alterations made based on ordinary technical knowledge and conventional means in the art without departing from the above-described technical concept of the present invention are included within the scope of the present invention.

[0032] like Figure 1 and Figure 3 As shown, the filter with anti-leakage function of filter element in this utility model is mainly composed of valve assembly 7, second sealing ring 6, filter element assembly 5, first sealing ring 4, filter housing 3, differential pressure indicator 2 and shaft elastic retaining ring 1.

[0033] like Figure 1 and Figure 3 As shown, valve assembly 7 is assembled with filter element assembly 5 and sealed by second sealing ring 6; filter element assembly 5 is assembled with differential pressure indicator 2 and sealed by first sealing ring 4; differential pressure indicator 2 is assembled with filter housing 3 and sealed by sealing ring, and fixed by shaft elastic retaining ring 1. Valve assembly 7 is secured by threads (…). Figure 1 The external thread on the rightmost surface is fixed to the accessory housing and sealed by a sealing ring.

[0034] Among them, such as Figure 4 As shown, the differential pressure indicator 2 has a large spring 12 inside, with a certain amount of compression space in the axial direction. The filter element assembly 5 and the differential pressure indicator 2 are assembled in a state of certain pre-compression in the axial direction (the compression of the large spring 12 is 1mm to 2mm). The fuel medium can flow inside the filter, such as... Figure 2 As shown, the filter element assembly 5 filters impurities to achieve the function of removing impurities. Figure 2 The middle arrow shows the path of fuel flowing normally from the inlet (annular gap) between the filter element assembly 5 and the filter housing 3 into the filter element assembly 5 inside the filter housing 3, and then out through the valve assembly 7.

[0035] The differential pressure indicator 2 consists of a temperature sensor assembly 8, a signal cap assembly 9, a pagoda spring 14, an indicator housing 15, a magnet assembly 10, a sleeve 11, a large spring 12, and a locking nut 13, etc., see below. Figure 4Wherein the temperature sensor assembly 8, the signal cap assembly 9, the indicator housing 15, the magnetic steel assembly 10 are the traditional functional structures of the existing pressure differential indicator (for example, CN213699081U, 2021.07.16, a pressure differential indicator). The indicator housing 15 and the large spring 12 are assembled and movable within the sleeve 11 body of the pressure differential indicator 2. The indicator housing 15 has a certain displacement activity in the axial direction due to the compression and elongation of the large spring 12. When the filter cartridge assembly 5 is not installed, the high pressure chamber pressure of the pressure differential indicator 2 is equal to the low pressure chamber pressure (i.e. no pressure differential state), so the pre-compressed large spring 12 will elongate, and the position of the magnetic steel assembly 10 is limited by the lock nut 13 at this time, thereby causing the large spring 12 to move the internal components of the indicator housing 15 except the magnetic steel assembly 10 axially, resulting in the relative displacement of the magnet on the magnetic steel assembly 10 and the annular magnet on the signal cap assembly 9, changing the direction of the force between the two magnets. The force between the magnetic steel assembly 10 and the signal cap assembly 9 causes the signal cap assembly 9 to be in the tendency of being ejected. When the specified temperature condition is reached (which can be set by changing the temperature sensing memory metal sheet 16), the temperature sensing memory metal sheet 16 deforms and no longer limits the movement of the signal cap assembly 9. Finally, the indicator cap of the signal cap assembly 9 on the pressure differential indicator 2 is ejected, giving an alarm signal, realizing the filter cartridge anti-leakage function.

[0036] The magnetic steel assembly 10 is a long rod structure with a piston, Figure 4 The magnetic steel assembly 10 is shown. The left end is a cylindrical magnet, the right side of the magnet is a piston structure, the piston structure is connected to the retaining ring screwed into the indicator housing 15 through a small spring (here, small means that the outer diameter of the small spring is smaller than that of the large spring 12), the left side of the piston structure is the high pressure chamber (the surface of the indicator housing 15 has a through hole communicating with the inner cavity of the filter housing 3), and the right side is the low pressure chamber (the pressure in the filter cartridge is transmitted to the right side of the piston structure through the axial second end of the sleeve 11 to the inside of the sleeve 11). The magnetic steel assembly 10 extends through the retaining ring and the large spring 12 to the outside of the axial second end of the sleeve 11, and is then limited by the lock nut 13 outside the axial second end of the sleeve 11.

[0037] The indicator housing 15 can slide within the sleeve 11, and the action of the signal cap assembly 9 is realized by the force of the large spring 12.

[0038] The signal cap assembly 9 cooperates with the conical spring 14 and the ball (copper ball in this embodiment) inside the indicator housing 15 to realize the latching function of the signal cap assembly 9. Specifically, Figure 4As shown, the left end of the indicator housing 15 is internally formed with a stepped cylindrical cavity, the left cylindrical cavity has a larger inner diameter and the right cylindrical cavity has a smaller inner diameter, the smaller inner diameter cavity is internally installed with the ball and the cone spring 14, the indicator cap of the signal cap assembly 9 is installed in the larger inner diameter cavity, and the cap body of the signal cap assembly 9 is slidingly sleeved outside the cavity. When the signal cap assembly 9 is not popped out (non-alarm state, the filter element assembly 5 is correctly installed), the indicator cap in the signal cap assembly 9 compresses the cone spring 14 through the ball. When the signal cap assembly 9 is popped out (alarm state, the filter element assembly 5 is not installed), the indicator cap in the signal cap assembly 9 moves to the left (arrow direction in the figure) away from the ball, so the ball also moves under the push of the cone spring 14 until it falls into the larger inner diameter cavity. Since the filter is in a horizontal state at this time, the indicator cap cannot continue to move when it moves to the right and is blocked by the ball at the step between the two cavities with different inner diameters, so it cannot be reset, achieving the locking function. When the filter is placed vertically, the ball can overcome the step and enter the smaller inner diameter cavity, thereby completing the reset of the indicator cap. Figure 4

[0039] When the filter element leak-proof installation function alarm occurs, the maintenance personnel need to redevelop maintenance and installation work. The maintenance personnel need to manually press the indicator cap of the differential pressure indicator 2, correctly complete the installation of the filter, and the filter can achieve normal function, and the product can be used normally.

[0040] As shown in Figure 1 and Figure 3 , the valve assembly 7 comprises a shell, a valve seat and a valve, the shell is installed at the axial second end of the filter element assembly 5, the end face of the shell is provided with a fuel bypass valve inlet, the valve seat is a hollow structure and extends through the shell to the filter element of the filter element assembly, the axial first end of the valve seat is a fuel first inlet, the axial second end is a fuel outlet, the circumferential surface of the valve seat is provided with a plurality of small holes as fuel second inlets, and the valve is slidingly connected to the outer surface of the valve seat through a spring.

[0041] As shown in Figure 5 , when the filter element in the filter element assembly 5 is blocked, the fuel cannot continue to flow normally into the filter element from the normal fuel inlet (the annular gap between the filter element assembly 5 and the filter housing 3), when the fuel pressure is greater than the deformation force of the spring in the valve assembly 7, the fuel pressure pushes open the valve of the valve assembly 7 and flows into the shell from the fuel bypass valve inlet on the end face of the shell, then flows into the inner cavity of the valve seat through the openings (fuel second inlets) on the outer surface of the valve seat, and then flows out from the fuel outlet on the valve seat, achieving the fuel bypass function when the filter element is blocked, Figure 5 , the arrow shows the flow path of the fuel when the filter element is blocked.

[0042] When the filter is used normally, the differential pressure indicator 2 alarms when the differential pressure before and after the filter element reaches a specified value, and the filter needs to be normally maintained.​

[0043] As an example, when the temperature and oil pressure difference is normal, the signal cap assembly 9 is kept in the reset state under the force of the magnetic steel assembly 10; when the temperature is higher than T1℃, the temperature sensing memory metal sheet 16 on the temperature sensor assembly 8 is unfolded from the bent state in the Figure 4 , and no longer hinders the axial sliding of the signal cap assembly 9, when the oil pressure difference reaches the indicating value (0.30-0.42) MPa, the oil pressure will push the piston on the magnetic steel assembly 10, so that the magnet at the end of the piston is opposite to the annular magnet of the signal cap assembly 9 by a certain distance, at this time, the magnetic force between the signal cap assembly 9 and the magnetic steel assembly 10 becomes opposite, so that the signal cap assembly 9 is popped out to achieve the purpose of alarm. When the temperature is lower than T2 (T2

[0044] The use process of the filter of the utility model is as follows:

[0045] 1. When the filter works normally, the working oil liquid flows into the filter housing 3 from the oil liquid inlet, and flows out from the oil liquid outlet after being filtered by the filter core assembly 5, as shown by the arrow in the Figure 2 , at this time, the filter core assembly 5 of the filter is normally installed with the differential pressure indicator 2, and is in the pre-tightening state (1mm-2mm) in the axial direction, the differential pressure indicator 2 does not alarm under the condition of no pressure and at the specified temperature value. If the filter core assembly 5 is not installed on the filter, the differential pressure indicator 2 has no pre-tightening pressure in the axial direction, the large spring 12 on the differential pressure indicator 2 pushes the zero components inside the indicator housing 15, the force between the magnetic steel assembly 10 and the signal cap assembly 9 makes the indicating cap in the tendency of being popped out, the indicating cap of the differential pressure indicator 2 is popped out under the condition of reaching the specified temperature (which can be set), an alarm signal is given, and the filter core anti-leakage installation function of the filter is realized.

[0046] 2. When the filter core in the filter is blocked, the fuel cannot continue to flow into the filter core from the normal fuel inlet (the annular gap between the filter core assembly 5 and the filter housing 3), when the fuel pressure is greater than the deformation force of the spring in the valve assembly 7, the fuel pressure pushes open the valve of the valve assembly 7 and flows into the housing from the fuel bypass valve inlet on the end surface of the housing, and then flows into the inner cavity of the valve seat through the opening (the second fuel inlet) on the outer surface of the valve seat, and then flows out from the fuel outlet on the valve seat, realizing the fuel bypass function when the filter core is blocked, Figure 5 , the arrow shows the flow path of the fuel when the filter core is blocked.

[0047] Those skilled in the art can make various modifications to the present application according to the actual situation. The general principles defined in the present application can be implemented in other implementations without departing from the essence thereof. Therefore, the present application will not be limited to the structures shown in the specific embodiments, but will conform to the widest scope consistent with the principles and characteristics set forth in the claims of the present application.

Claims

1. A filter with a leak-proof filter cartridge function, characterized in that: The differential pressure indicator (2), the filter housing (3), the filter element assembly (5) and the valve assembly (7) are coaxially assembled, wherein: The filter element assembly (5) comprises a radial inlet and axial outlet filter element, and is installed in the inner cavity of the filter housing (3); The differential pressure indicator (2) is connected to the axial first end of the filter element assembly (5) through the axial first end of the filter housing (3), the high pressure cavity of the differential pressure indicator (2) is located outside the filter element assembly (5) and communicates with the inner cavity of the filter housing (3), and the low pressure cavity of the differential pressure indicator (2) is located inside the filter element of the filter element assembly (5); The differential pressure indicator (2) mainly comprises an indicator housing (15), a temperature sensor assembly (8), a signal cap assembly (9), a magnetic steel assembly (10), a sleeve (11) and a large spring (12), wherein the differential pressure indicator (2) is connected to the axial first end of the filter element assembly (5) through the sleeve (11), the indicator housing (15) is slidingly connected in the sleeve (11), the large spring (12) is located in the sleeve (11) and tightly contacts the axial second end of the indicator housing (15) and the inner wall of the sleeve (11) at both ends, the signal cap assembly (9) comprises an annular magnet and is slidingly connected inside the axial first end of the indicator housing (15), the temperature sensor assembly (8) is fixed inside the axial first end of the indicator housing (15) and comprises a temperature sensitive memory metal sheet (16), the free end of the temperature sensitive memory metal sheet (16) points to the signal cap assembly (9), the magnetic steel assembly (10) is slidingly connected inside the indicator housing (15), the axial first end of the magnetic steel assembly (10) is provided with a magnet with an outer diameter smaller than the inner diameter of the annular magnet, and a piston is further provided on the magnetic steel assembly (10), the piston divides the inside of the indicator housing (15) into a high pressure cavity and a low pressure cavity, and the axial second end of the magnetic steel assembly (10) extends to the outside of the sleeve (11); The valve assembly (7) is connected to the axial second end of the filter element assembly (5) through the axial second end of the filter housing (3), there is an annular gap between the valve assembly (7) and the filter housing (3) to form a fuel inlet channel, the valve assembly (7) is provided with a fuel bypass valve inlet on the end face outside the filter housing (3), and the valve assembly (7) further comprises a valve driven by a spring for sealing the bypass valve inlet.

2. The filter with filter element leakage prevention function according to claim 1, wherein: The differential pressure indicator (2) and the filter element assembly (5) comprise a first sealing ring (4) as a radial sealing structure; The valve assembly (7) and the filter element assembly (5) comprise a second sealing ring (6) as a radial sealing structure.

3. The filter with filter core leakage prevention function according to claim 1, characterized in that: The differential pressure indicator (2) is assembled at the axial first end of the filter housing (3) through the shaft elastic retainer ring (1).

4. The filter with filter element leakage prevention function according to claim 1, wherein: The indicator housing (15) is further provided with a reset channel, the reset channel comprises at least two cavities with different inner diameters, and the signal cap assembly (9) is slidingly connected outside the reset channel. The differential pressure indicator (2) further comprises a conical spring (14) and a ball, the conical spring (14) and the ball are assembled in the cavity with the minimum inner diameter in the reset channel.

5. The filter with filter core leakage prevention function according to claim 4, characterized in that: The signal cap assembly (9) comprises a cap body and an indicating cap, the cap body is tubular, the indicating cap is fixed on the axial first end surface of the cap body and located in the cavity with the maximum inner diameter in the reset channel, a ring-shaped magnet is embedded in the axial second end of the cap body, and the signal cap assembly (9) is slidingly connected to the outside of the reset channel through the cap body.

6. The filter with filter core leakage prevention function according to claim 1, characterized in that: A stop ring and a small spring are further arranged in the indicator housing (15), the stop ring is installed in the low-pressure cavity of the indicator housing (15) through screw threads, and the small spring is located in the low-pressure cavity and tightly contacts the piston and the stop ring at both ends.

7. The filter with filter core leakage prevention function according to claim 1, characterized in that: The magnetic steel assembly (10) is installed with a locking nut (13) on the axial second end outside the sleeve (11).

8. The filter with filter core leakage prevention function according to claim 1, characterized in that: The valve assembly (7) comprises a shell, a valve seat and a valve, the shell is installed on the axial second end of the filter element assembly (5), an oil bypass valve inlet is formed on the end surface of the shell, the valve seat is a hollow structure and extends to the filter element in the filter element assembly (5) after penetrating the shell, the axial first end of the valve seat is an oil first inlet, the axial second end is an oil outlet, an oil second inlet is formed on the circumferential surface of the valve seat, and the valve is slidingly connected to the outer surface of the valve seat through a spring.

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