Water removal filters for onboard oxygen systems

Abstract

The present invention discloses a dewatering filter for an airborne oxygen system, wherein an air inlet pipe is provided at the upper end of a shell, a water outlet hole is provided at the bottom of the shell, an air outlet pipe is provided on the outer wall of the shell, a spiral tooth plate and a filter body are installed in the shell, a vertical filter body is located at the center of the shell, the spiral tooth plate is installed around the middle and upper outer wall of the filter body, a gap is provided between the outer wall of the spiral tooth plate and the inner wall of the shell, a filter air inlet is provided at the lower part of the filter body, a filter air outlet is provided at the upper part of the filter body, and the filter air outlet is connected to the air outlet pipe. The present invention highly integrates a dewatering device and a filter device into one device, which has both dewatering and filtering functions, so that the air entering the oxygen concentrator meets the high quality requirements of dryness and cleanliness, prolongs the life of the airborne oxygen concentrator, and significantly reduces the volume and weight of the entire oxygen system, reducing the flight load and cost of the aircraft.

Description

Technical Field

[0001] The invention relates to a filtering device used in an oxygen production system, in particular to a water removal filter used in an airborne oxygen system. Background Art

[0002] The onboard oxygen system is a system used to prepare oxygen on the aircraft. It uses the air in the environment as the gas source and prepares oxygen through an oxygen generator by separating oxygen and nitrogen. Since air is a multi-component mixed gas, in addition to oxygen, nitrogen, rare gases, water vapor, carbon dioxide, acetylene and hydrocarbons, it also contains solid impurities such as dust. These impurities can cause harm to the oxygen generator, such as blocking the gas pipeline and reducing the life of the molecular sieve. Therefore, it is necessary to remove water and filter the air before it enters the molecular sieve.

[0003] In traditional airborne oxygen systems, air dehydration and filtration are performed separately using separate equipment, which increases the volume and weight of the entire oxygen system, and increases the aircraft's flight load and cost. Some airborne oxygen systems only have one of the functions of dehydration and filtration, so the air entering the oxygen concentrator is difficult to meet high quality requirements, which will damage the oxygen concentrator and reduce its life.

[0004] At present, there are two main air filtration methods for traditional airborne oxygen systems, and each has its own disadvantages, as follows: one is wet filtration, which is to use oil film to adhere to solid particles in the air. This method is easy to cause the surface oil film to be saturated and fail during dust removal in dusty environments, and has a short service life; the other is dry filtration, which is to use fabric mesh to block dust in the air with a diameter smaller than the aperture, but it is easy to get clogged, resulting in reduced dust removal efficiency.

[0005] In addition, in order to promptly understand whether the filter of the onboard oxygen system is clogged, a differential pressure switch is generally used to compare and monitor the air pressure at the inlet and outlet ends of the filter. Once the air pressure at the inlet end is significantly greater than the air pressure at the outlet end, it is judged that the filter is clogged, and a real-time alarm is issued through the alarm on the differential pressure switch.

[0006] However, traditional differential pressure switches generally use electronic structures such as air pressure sensors or mechanical structures such as elastic sheets. They have problems such as large size, low sensitivity, and poor sealing. They are not suitable for use in airborne oxygen systems that need to minimize size and weight. Summary of the invention

[0007] The object of the present invention is to provide a water removal filter for an onboard oxygen system which integrates water removal and filtering functions in order to solve the above problems.

[0008] The present invention achieves the above-mentioned purpose through the following technical solutions:

[0009] A dewatering filter for an onboard oxygen system comprises a shell, wherein an air inlet pipe is provided at the upper end of the shell, a water outlet hole is provided at the bottom of the shell, an air outlet pipe is provided on the outer wall of the shell, a spiral tooth piece for dewatering gas and a filter body for filtering gas are installed in the shell, the filter body is vertically located at the center of the shell, the spiral tooth piece is installed around the middle and upper outer wall of the filter body, a gap is provided between the outer wall of the spiral tooth piece and the inner wall of the shell, a filter air inlet is provided at the lower part of the filter body and the filter air inlet is located above the water outlet hole of the shell, a filter air outlet is provided at the upper part of the filter body and the filter air outlet is communicated with the air outlet pipe.

[0010] In the above structure, the spiral tooth blades are conventional components used to make the gas form a cyclone to achieve water-gas separation and achieve the purpose of water removal; the filter body is used for gas filtration, and conventional filter bodies of various structures can be selected according to needs. At the same time, the filter body has a further blocking and dewatering effect on the remaining water in other parts, thereby achieving a better dewatering effect; the focus of the present invention is to combine the dewatering device and the filtering device together to achieve the functions of dewatering and filtering at the same time, and utilize the layout of gas flowing downward to separate and remove water circumferentially and gas gathering to the middle for upstream filtration to achieve efficient integration of the two structures and achieve the purpose of high integration.

[0011] Preferably, in order to facilitate installation, cleaning and replacement of the filter body, the filter body includes a filter element seat and a filter element cartridge installed on the filter element seat. The filter element built into the filter element cartridge can effectively filter out dust and other impurities in the gas, has the advantages of large flow area and small gas flow resistance, and is also easy to clean and replace.

[0012] Preferably, in order to facilitate the centralized discharge of water flowing down the inner wall of the shell after gas separation, the bottom inner wall of the shell is conical and the water outlet is located at the center of the cone. The aperture of the water outlet is set according to actual needs, and the aperture is minimized as much as possible while ensuring timely drainage to minimize gas loss.

[0013] Furthermore, in order to monitor the pressure difference between the inlet pressure and the outlet pressure of the filter body in real time and issue an alarm when the pressure difference is too large, a diaphragm-type pressure difference switch for monitoring the pressure difference between the inlet pressure and the outlet pressure of the filter body is installed on the shell or the outlet pipe. The diaphragm-type pressure difference switch includes a switch shell, a diaphragm, a spring, a valve rod and a contact conductor. The switch shell is provided with a shell inner cavity. The diaphragm is placed in the shell inner cavity and isolates the shell inner cavity into an upper inner cavity and a lower inner cavity. Positions in the switch shell corresponding to the upper inner cavity and the lower inner cavity are respectively provided with a valve rod for The air on the inlet side of the filter body is introduced into the air inlet collection hole of the upper inner cavity, and the air on the outlet collection hole of the filter body is used to introduce the air on the outlet side of the filter body into the lower inner cavity. The valve rod and the contact conductor are both placed in the lower inner cavity and are both electrical conductors. The upper end of the vertical valve rod is in contact with the diaphragm and maintains upward stress through the spring. The contact conductor is located below the valve rod. After the diaphragm is bent downward, the lower end of the valve rod can be in conductive contact with the upper surface of the contact conductor. The valve rod and the contact conductor serve as two connection ends respectively and are connected to the alarm through wires. The filter body will inevitably become clogged after being used for a period of time. The diaphragm-type differential pressure switch can monitor the pressure difference between the inlet pressure and the outlet pressure of the filter body in real time and send out an alarm signal when the pressure difference is too large, which is conducive to the staff to clean or replace the filter body in time; the diaphragm-type differential pressure switch adopts a mechanical pressure-sensing structure, has high sensitivity and long life, and can monitor the pressure difference by utilizing the elasticity of the diaphragm and the auxiliary effect of the spring, and has the advantages of simple structure, small size and light weight; the above-mentioned diaphragm adopts a conventional diaphragm with an annular groove, the part of the diaphragm located on the outer periphery of the annular groove is used for connection and installation, and the part located within the annular groove is used to form an elastic structure, which will bend to one side when subjected to external force, and will return to its original state after the external force is lost, and can achieve better elastic effect in combination with the spring, and it is also convenient to adjust the size of the pressure required for the diaphragm to bend, and the spring is in contact with the part of the diaphragm located within the annular groove; the above-mentioned alarm can adopt a conventional auditory or / and visual alarm, and the principle of connecting the alarm to the two terminals to realize the alarm is very simple, that is, the two terminals are connected in series to the power input end of the alarm.

[0014] Preferably, in order to facilitate the installation of the diaphragm, the valve rod and the contact conductor and to facilitate the connection with the alarm, the diaphragm type differential pressure switch also includes a non-metallic ring, a screw ring, a metal guide ring, a stud and a non-metallic sleeve. The lower end of the switch housing is sealed and connected to the outer wall of the shell or the outer wall of the air outlet pipe to form a sealed lower inner cavity. The non-metallic ring is composed of an integrally formed horizontal plate and a circular ring with a vertical axial direction, and a plurality of vertical through holes are provided on the horizontal plate. The upper end of the circular ring of the non-metallic ring presses the diaphragm against the corresponding cavity wall of the inner cavity of the shell, and the screw ring is threadedly connected to the corresponding cavity wall of the inner cavity of the shell and the non-metallic ring The lower end of the circular ring is pressed upward, a vertical center through hole is provided at the center position of the horizontal plate of the non-metallic ring and the metal guide ring is installed in the center through hole, the valve rod passes through the vertical through hole of the metal guide ring and can slide vertically in close contact, the upper and lower ends of the spring are respectively in contact or connected with the upper end of the valve rod and the horizontal plate of the non-metallic ring, the metal guide ring serves as a connecting end conductively connected to the valve rod, the stud is threadedly connected to the outer wall of the shell or the outer wall of the outlet pipe at a corresponding position, the non-metallic sleeve is sleeved on the stud, and the contact conductor is sleeved outside the non-metallic sleeve.

[0015] Preferably, in order to facilitate processing and assembly, the shell includes an upper shell and a lower shell connected to each other, and an integrally formed inverted "L"-shaped tube is provided in the upper shell. The gear mounting seat is mounted on the lower outer wall of the inverted "L"-shaped tube through its own internal thread, and the upper end of the spiral gear is mounted on the outer wall of the gear mounting seat through its own internal thread.

[0016] The beneficial effects of the present invention are:

[0017] The present invention integrates the dehydration device and the filtering device into one device, which has both dehydration and filtering functions, so that the air entering the oxygen concentrator meets the high quality requirements of dryness and cleanliness, prolongs the life of the airborne oxygen concentrator, and significantly reduces the volume and weight of the entire oxygen system, reducing the flight load and cost of the aircraft; by adopting a diaphragm type differential pressure switch with a simple structure, small volume, light weight and high sensitivity, the pressure difference between the inlet pressure and the outlet pressure of the filter body is monitored in real time and an alarm is given, thereby avoiding the problem of poor filtering effect due to clogging of the filter body, and is particularly suitable for air dehydration and filtering of airborne oxygen systems; in the diaphragm type differential pressure switch, the pre-compression amount of the spring is changed by adjusting the screw ring, thereby changing the pressure difference required to push the diaphragm, and the function of adjustable alarm pressure difference value of the differential pressure switch can be realized. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a partially cutaway perspective view of a water removal filter for an airborne oxygen system according to the present invention;

[0019] Figure 2is a front cross-sectional view of a water removal filter for an airborne oxygen system according to the present invention;

[0020] Figure 3 yes Figure 1 Enlarged view of "A". DETAILED DESCRIPTION

[0021] The present invention will be further described below in conjunction with the accompanying drawings:

[0022] like Figure 1 , Figure 2 and Figure 3 As shown, the water removal filter for the airborne oxygen system of the present invention comprises a housing (see Figure 1 and Figure 2 The upper shell 3 and the lower shell 8 in the shell are provided with an air inlet pipe 1 at the upper end of the shell, a water outlet hole 18 is provided at the bottom of the shell, an air outlet pipe 9 is provided on the outer wall of the shell, and a spiral tooth piece 13 for removing water from the gas and a filter body for filtering the gas are installed in the shell (see Figure 2 The filter element seat 15 and the filter element barrel 14 are arranged in the middle of the shell, the vertical filter body is located at the center of the shell, the spiral gear pieces 13 are installed around the middle and upper outer wall of the filter body, and a gap is provided between the outer wall of the spiral gear pieces 13 and the inner wall of the shell to facilitate the centrifugally separated water to flow down along the inner wall of the shell, the lower part of the filter body is provided with a filter air inlet and the filter air inlet is located above the water outlet hole 18 of the shell, the upper part of the filter body is provided with a filter air outlet and the filter air outlet is connected to the outlet pipe 9.

[0023] Preferably, the filter body includes a filter element seat 15 and a filter element barrel 14 installed on the filter element seat 15; the bottom inner wall 17 of the shell is conical and the water outlet 18 is located at the center of the cone; a connecting mounting portion 5 is provided on the outlet pipe 9 (or on the shell), and a diaphragm type differential pressure switch 4 for monitoring the pressure difference between the inlet pressure and the outlet pressure of the filter body (in this case, the gas pressure at both ends of the filter element barrel 14) is installed on the connecting mounting portion 5. The diaphragm type differential pressure switch 4 includes a switch housing 41, a diaphragm 43, a spring 46, a valve rod 44 and a contact conductor 50. The switch housing 41 is provided with a housing inner cavity, and the diaphragm 43 is placed in the housing inner cavity and isolates the housing inner cavity into an upper inner cavity. 42 and the lower inner cavity 49, the positions corresponding to the upper inner cavity 42 and the lower inner cavity 49 in the switch housing 41 are respectively provided with an inlet collection hole 40 for introducing the inlet side gas of the filter body into the upper inner cavity 42 and an outlet collection hole 51 for introducing the outlet side gas of the filter body into the lower inner cavity 49, the specific implementation of the inlet collection hole 40 and the outlet collection hole 51 depends on the actual situation, as long as the function can be achieved, the valve rod 44 and the contact conductor 50 are both placed in the lower inner cavity 49 and are both electrical conductors, the upper end of the vertical valve rod 44 contacts the diaphragm 43 and maintains upward stress through the spring 46, the contact conductor 50 is located below the valve rod 44, and the lower end of the valve rod 44 is bent downward after the diaphragm 43 It can be in conductive contact with the upper surface of the contact conductor 50, and the valve rod 44 and the contact conductor 50 are respectively used as two connection ends and are respectively connected to the alarm 6 through wires; the diaphragm type differential pressure switch 4 also includes a non-metallic ring 47, a screw ring 48, a metal guide ring 45, a stud 53 and a non-metallic sleeve 52, and the lower end of the switch housing 41 is sealed and connected to the outer wall of the connecting and mounting part 5 on the outlet pipe 9 (it can also be the outer wall of the shell) to form a sealed lower inner cavity 49, the non-metallic ring 47 is composed of an integrally formed horizontal plate and a circular ring with a vertical axial direction, and a plurality of vertical through holes are provided on the horizontal plate, and the upper end of the circular ring of the non-metallic ring 47 presses the diaphragm 43 against the corresponding cavity wall of the inner cavity of the shell, and the screw ring 48 is in contact with the inner cavity of the shell. The corresponding cavity wall is threadedly connected and the lower end of the circular ring of the non-metallic ring 47 is pressed upward. A vertical central through hole is provided at the central position of the horizontal plate of the non-metallic ring 47 and the metal guide ring 45 is installed in the central through hole. The valve rod 44 passes through the vertical through hole of the metal guide ring 45 and can slide vertically in close contact. The upper and lower ends of the spring 46 are respectively in contact or connected with the upper end of the valve rod 44 and the horizontal plate of the non-metallic ring 45. The metal guide ring 45 serves as a connecting end conductively connected to the valve rod 44. The stud 53 is threadedly connected to the outer wall of the connecting and mounting portion 5 on the outlet pipe 9 (it can also be the outer wall of the shell) at a corresponding position. The non-metallic sleeve 52 is sleeved on the stud 53, and the contact conductor 50 is sleeved outside the non-metallic sleeve 52.The housing comprises an upper housing 3 and a lower housing 8 connected to each other, wherein an integrally formed inverted "L"-shaped tube 12 is provided in the upper housing 3, a tooth piece mounting seat 11 is mounted on the lower outer wall of the inverted "L"-shaped tube 12 through its own internal thread, and the upper end of the spiral tooth piece 13 is mounted on the outer wall of the tooth piece mounting seat 11 through its own internal thread. ;

[0024] Figure 1 Also shown is the gas source collection component 2, Figure 2 Also shown is a gap 16 between the outer wall of the filter element seat 15 and the inner wall of the lower housing 8. The gap 16 is used for centrifugally separated water to flow along the inner wall of the lower housing 8 to the water outlet 18. These are conventional adaptive structures.

[0025] like Figure 1-Figure 3 As shown, during operation, the compressed air used for oxygen production enters the upper shell 3 from the air inlet pipe 1, passes through the gas channel 10 and quickly impacts the spiral tooth plate 13 from top to bottom to form a vortex, and the water droplets in the gas undergo centrifugal motion, the water droplets are separated from the gas and attached to the inner wall of the upper shell 3, and a large number of accumulated water droplets are affected by gravity, flow down along the inner wall of the upper shell 3 and the inner wall of the lower shell 8, converge at the inner wall 17 of the conical bottom, and are discharged to the outside of the shell through the water outlet 18; at the same time, in this process, the airflow will also flush the water droplets attached to the inner wall of the shell, causing it to flow down quickly and be discharged outside the shell; the air after most of the water is removed enters the filter cartridge 14 from bottom to top, the dust particles are blocked by the filter element in the filter cartridge 14, and the filtered air is discharged through the inverted "L"-shaped tube 12 and the through hole 7 of the air outlet pipe 9 and is sent to the oxygen generator.

[0026] After being used for a period of time, a large amount of foreign particles will be attached to the filter cartridge 14, causing some of the small holes on the surface of the filter cartridge 14 to be blocked, resulting in a decrease in the dust filtering effect. At this time, the filter cartridge 14 needs to be cleaned or replaced. The diaphragm pressure differential switch 4 is used to monitor in real time whether the filter cartridge 14 is blocked. Its working principle is: the air on the intake side of the filter cartridge 14 enters the upper inner cavity 42 in the inner cavity of the shell through the intake collection hole 40, and the gas on the outlet side of the filter cartridge 14 enters the lower inner cavity 49 in the inner cavity of the shell through the outlet collection hole 51. If the filter cartridge 14 is not blocked, the air pressure in the upper inner cavity 42 is basically the same as the air pressure in the lower inner cavity 49, the diaphragm 43 will not bend, the valve rod 44 will not contact the contact conductor 50, and the alarm 6 is in In the disconnected state, there will be no alarm; when the filter cartridge 14 is blocked and blocked to a certain extent, the air on the outlet side of the filter cartridge 14 is reduced and the air pressure is reduced, and the air pressure in the upper inner cavity 42 is significantly greater than the air pressure in the lower inner cavity 49. The diaphragm 43 will overcome its own elasticity and the elasticity of the spring 46 and bend downward until the valve rod 44 contacts the contact conductor 50. The alarm 6 is in the on state and sends out an alarm signal. At this time, the staff will promptly understand the problem of filter cartridge 14 blockage and solve this problem by cleaning or replacing it; after the blockage problem is resolved, the air pressure in the upper inner cavity 42 and the air pressure in the lower inner cavity 49 are restored to balance, and the valve rod 44 rebounds upward and resets under the elasticity of the diaphragm 43 and the elasticity of the spring 46 to resume normal working state.

[0027] The above embodiments are only preferred embodiments of the present invention and are not limitations of the technical solutions of the present invention. Any technical solution that can be implemented on the basis of the above embodiments without creative work should be deemed to fall within the scope of protection of the patent of the present invention.

Claims

1. A dewatering filter for an airborne oxygen system, comprising a housing, an air inlet pipe is provided at the upper end of the housing, a water outlet hole is provided at the bottom of the housing, and an air outlet pipe is provided on the outer wall of the housing, characterized in that: The shell is provided with a spiral tooth piece for removing water from the gas and a filter body for filtering the gas, the vertical filter body is located at the center of the shell, the spiral tooth piece is installed around the outer wall of the middle and upper part of the filter body, a gap is provided between the outer wall of the spiral tooth piece and the inner wall of the shell, a filter air inlet is provided at the lower part of the filter body and the filter air inlet is located above the water outlet hole of the shell, a filter air outlet is provided at the upper part of the filter body and the filter air outlet is connected to the outlet pipe; a diaphragm type differential pressure switch for monitoring the pressure difference between the inlet pressure and the outlet pressure of the filter body is installed on the shell or the outlet pipe, and the diaphragm type differential pressure switch comprises a switch housing, a diaphragm, a spring, A valve rod and a contact conductor, the switch housing is provided with a housing inner cavity, the diaphragm is placed in the housing inner cavity and separates the housing inner cavity into an upper inner cavity and a lower inner cavity, positions in the switch housing corresponding to the upper inner cavity and the lower inner cavity are respectively provided with an inlet collection hole for introducing the inlet side gas of the filter body into the upper inner cavity and an outlet collection hole for introducing the outlet side gas of the filter body into the lower inner cavity, the valve rod and the contact conductor are both placed in the lower inner cavity and are both electrical conductors, the upper end of the vertical valve rod is in contact with the diaphragm and maintains an upward stress through the spring, the contact conductor is located below the valve rod, and after the diaphragm is bent downward, the lower end of the valve rod can contact the contact conductor The upper surface of the conductor is in conductive contact, the valve rod and the contact conductor are respectively used as two connection ends and are respectively connected to the alarm through wires; the diaphragm type differential pressure switch also includes a non-metallic ring, a screw ring, a metal guide ring, a stud and a non-metallic sleeve, the lower end of the switch shell is sealed and connected to the outer wall of the shell or the outer wall of the outlet pipe to form a sealed lower inner cavity, the non-metallic ring is composed of an integrally formed horizontal plate and a circular ring with a vertical axial direction and a plurality of vertical through holes are provided on the horizontal plate, the upper end of the circular ring of the non-metallic ring presses the diaphragm against the corresponding cavity wall of the inner cavity of the shell, the screw ring is threadedly connected to the corresponding cavity wall of the inner cavity of the shell and presses the lower end of the circular ring of the non-metallic ring upward, the horizontal plate of the non-metallic ring A vertical center through hole is provided at the center position and the metal guide ring is installed in the center through hole, the valve rod passes through the vertical through hole of the metal guide ring and can slide vertically in close contact, the upper and lower ends of the spring are respectively in contact or connected with the upper end of the valve rod and the horizontal plate of the non-metallic ring, the metal guide ring serves as a connecting end conductively connected to the valve rod, the stud is threadedly connected to the outer wall of the shell or the outer wall of the air outlet pipe at a corresponding position, the non-metallic sleeve is sleeved on the stud, and the contact conductor is sleeved outside the non-metallic sleeve; the filter body includes a filter element seat and a filter element barrel installed on the filter element seat; the bottom inner wall of the shell is conical and the water outlet is located at the center of the cone.

2. The water removal filter for an airborne oxygen system according to claim 1, characterized in that: The shell includes an upper shell and a lower shell that are connected to each other. An integrally formed inverted "L"-shaped tube is provided in the upper shell. The gear plate mounting seat is mounted on the lower outer wall of the inverted "L"-shaped tube through its own internal thread. The upper end of the spiral gear plate is mounted on the outer wall of the gear plate mounting seat through its own internal thread.

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