Sand discharging fan for helicopter

Abstract

The utility model discloses a sand discharging fan for a helicopter, which comprises a cylindrical duct shell, a fan blade, a fan blade, a fan blade, a fan blade, a fan blade, a fan blade, a fan blade, a fan blade, a fan blade, a fan blade and a fan blade, the fan motor is coaxially arranged in the internal channel; an airflow channel is reserved between the shell of the fan motor and the inner surface of the duct shell, and the fan motor and the duct shell are connected through fan stationary blades; one end of the fan motor close to the exhaust port is provided with a fan impeller; the one-way valve assembly is arranged at the exhaust port of the duct shell and comprises two semicircular cover plates and a fixing rod fixedly mounted in the exhaust port; the cover plate is rotationally connected with the fixing rod and is driven by the torsional spring; when the fan motor stops rotating, the torsional spring drives the two cover plates to cover the exhaust port; after the fan motor is started, airflow pushes the two cover plates to be folded outwards, so that the exhaust port is opened. The fan can quickly extract dust in a helicopter body through airflow, and the dust is prevented from accumulating in the helicopter body to cause mechanical faults.

Description

Technical Field

[0001] The utility model relates to the field of aircraft, in particular to a sand-removing fan for a helicopter. Background Art

[0002] When a helicopter flies at low altitude, it will encounter sand and dust problems. When a helicopter flies near the ground, due to the rotation of the rotor, it may cause the ground sand and dust to be lifted, forming the so-called "sand blindness" phenomenon. This phenomenon will seriously affect the flight safety of the helicopter, because the sand and dust may be sucked into the engine, causing engine wear or damage, and may also damage components such as the windshield, pitot tube, fan, and compressor blades of the helicopter.

[0003] Sandstorms or strong sand and dust weather are particularly harmful to helicopters, because the main components of sand and dust may melt at high temperatures and block the small holes on the surface of the engine blades, resulting in the failure of the gas film and the ablation and damage of the turbine blades. Therefore, the helicopter needs to timely discharge the sand and dust that enters the fuselage. Summary of the Utility Model

[0004] In view of the above-mentioned defects of the prior art, the utility model provides a sand-removing fan for a helicopter, which can discharge the sand and dust that enters the interior of the helicopter shell through air flow, avoiding the accumulation of sand and dust inside the helicopter.

[0005] To achieve the above object, the utility model provides a sand-removing fan for a helicopter, which comprises:

[0006] A sand-removing fan for a helicopter, which comprises:

[0007] A duct housing, which is cylindrical, and its internal passage extends to both sides, forming an air inlet and an air outlet at the two end faces of the duct housing respectively;

[0008] A fan motor, which is coaxially arranged in the internal passage; there is an air flow passage between the outer shell of the fan motor and the inner surface of the duct housing, and the two are connected by fan stator blades;

[0009] A fan impeller is installed at one end of the fan motor close to the air outlet, and the fan impeller is driven by the fan motor;

[0010] A one-way valve assembly is arranged at the air outlet of the duct housing, which comprises two semi-circular cover plates and a fixed rod fixedly installed in the air outlet; the cover plates are rotatably connected to the fixed rod and are driven by a torsion spring; when the fan motor stops rotating, the torsion spring drives the two cover plates to cover the air outlet; when the fan motor starts, the air flow generated by the fan impeller pushes the two cover plates to close outward, so that the air outlet is opened.

[0011] A further improvement of the present utility model lies in that wear-resistant coatings are provided on the inner surface of the duct housing, the surface of the fan motor, and the surface of the fan impeller.

[0012] A further improvement of the present utility model lies in that a plurality of connecting ear plates extending outward are provided at a position of the duct housing adjacent to the air inlet.

[0013] A further improvement of the present utility model lies in that the fan motor is an asynchronous motor, and its internal rotor is a cast copper rotor.

[0014] A further improvement of the present utility model lies in that the fan impeller includes an impeller disc and fan blades; the impeller disc is circular with an outer diameter larger than the outer shell of the fan motor, and its center is fixedly connected to the output shaft of the fan motor by bolts; the fan blades are fixedly arranged at the outer edge of the impeller disc and extend outward.

[0015] A further improvement of the present utility model lies in that the fan stator vane and the housing of the fan motor are of an integral structure; the outer end face of the fan stator vane abuts against the inner surface of the duct housing and is fixedly connected to the duct housing by bolts.

[0016] The device provided by the present utility model has the following technical effects:

[0017] 1. It can quickly extract the dust and sand inside the helicopter body through the airflow, avoiding the accumulation of dust and sand inside the body and causing mechanical failures.

[0018] 2. A one-way valve assembly is provided. When not working, the one-way valve assembly covers the exhaust port, which can prevent foreign objects from entering the helicopter body.

[0019] 3. Structures such as the fan impeller are provided with wear-resistant coatings, which can effectively improve the service life of structures such as the fan.

[0020] The concept, specific structure, and technical effects generated by the present utility model will be further described below in conjunction with the drawings to fully understand the purpose, features, and effects of the present utility model. Description of the Drawings

[0021] Figure 1 is a perspective view of the sand discharge fan for helicopters of the present utility model;

[0022] Figure 2 is another perspective view of the sand discharge fan for helicopters of the present utility model;

[0023] Figure 3 is a schematic cross-sectional view of the sand discharge fan for helicopters of the present utility model;

[0024] Figure 4 is a schematic view of the fan motor and the fan impeller. Detailed Implementation Modes

[0025] The following describes the implementation modes of the present utility model through specific examples. Those skilled in the art can easily understand other advantages and effects of the present utility model from the content disclosed in this specification. The present utility model can also be implemented or applied through other different specific implementation modes. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present utility model. It should be noted that, without conflict, the following embodiments and the features in the embodiments can be combined with each other.

[0026] It should be noted that the diagrams provided in the following embodiments only illustrate the basic concept of the present utility model in a schematic manner. Therefore, only the components related to the present utility model are shown in the diagrams, rather than being drawn according to the number, shape, and size of the components in actual implementation. The type, quantity, and ratio of each component in actual implementation can be arbitrarily changed, and the component layout type may also be more complex.

[0027] For the purpose of illustration, some exemplary embodiments of the present utility model are described. It should be understood that the present utility model can be implemented in other ways not specifically shown in the drawings.

[0028] As Figure 1 、 Figure 2 and Figure 3 shown, an embodiment of the present utility model provides a sand - discharging fan for a helicopter, which includes: a duct housing 10, a fan motor 20, and a check valve assembly 30. Among them:

[0029] The duct housing 10 is cylindrical, and its internal channel 11 extends to both sides, forming an air inlet and an air outlet at the two end faces of the duct housing 10 respectively; both the air inlet and the air outlet are circular, and their shapes are the same as the cross - section of the internal channel 11 of the duct housing 10.

[0030] The fan motor 20 is coaxially arranged in the internal channel; there is an air flow channel between the outer shell of the fan motor 20 and the inner surface of the duct housing 10, and the two are connected by fan stator blades 21. The fan motor 20 is an asynchronous motor, and its internal rotor is a cast - copper rotor. In this embodiment, the motor stator includes an iron core welded by silicon steel sheets, and high - temperature resistant polyimide enameled wire and impregnating varnish. The motor rotor includes a motor output shaft, a cast - copper rotor composed of silicon steel sheets and copper, and a limit baffle that can limit the position of the bearing.

[0031] A fan impeller 22 is installed at one end of the fan motor 20 adjacent to the air outlet, and the fan impeller 22 is driven by the fan motor 20;

[0032] The one-way valve assembly 30 is disposed at the exhaust port of the duct housing 10 and includes two semi-circular cover plates 31 and a fixing rod 32 fixedly installed in the exhaust port. The cover plates 31 are rotatably connected to the fixing rod and are driven by a torsion spring 33. When the fan motor 20 stops rotating, the torsion spring drives the two cover plates 31 to cover the exhaust port. When the fan motor 20 starts, the airflow generated by the fan impeller 22 pushes the two cover plates 31 to close outward, opening the exhaust port.

[0033] The inner surface of the duct housing, the surface of the fan motor, and the surface of the fan impeller are all provided with wear-resistant coatings. The wear-resistant coatings are prepared using existing materials and existing processes. The wear-resistant coating is composed of a diamond-like carbon insulating coating and a CoMoCrSi coating. The thickness of the diamond-like carbon insulating coating is approximately 3 μm, its friction coefficient is 0.15, the film hardness is approximately 2200 HV, it can be firmly bonded to aluminum alloy, and the applicable temperature is approximately 350 °C. The CoMoCrSi coating is an alloy coating containing elements such as Co, Cr, Mo, and Si. It has excellent high and low temperature resistance, chemical corrosion resistance, and friction resistance. The service temperature of the coating is as high as 800 °C, and it is applied to the outer surface of the sand discharge fan by plasma spraying, with a thickness of approximately 0.1 mm, providing a second layer of surface protection for the sand discharge fan.

[0034] In order to be fixed to the helicopter body, a plurality of connecting ear plates 12 extending outward are provided at the position of the duct housing 10 near the air inlet. The connecting ear plates 12 are fixedly attached to the helicopter body by bolts or rivets.

[0035] In this embodiment, the fan impeller 22 includes an impeller disk 23 and fan blades 24. The impeller disk 23 is circular with an outer diameter larger than the housing of the fan motor 20, and its center is fixedly connected to the output shaft of the fan motor 20 by bolts. The fan blades 24 are fixedly arranged at the outer edge of the impeller disk 23 and extend outward.

[0036] As Figure 4 shown, the fan stator vane 21 and the housing of the fan motor 20 are of an integral structure. The outer end face of the fan stator vane 21 abuts against the inner surface of the duct housing 10 and is fixedly connected to the duct housing 10 by bolts.

[0037] When the fan motor 20 rotates, the fan impeller 22 extracts the air inside the helicopter body from the air inlet of the duct housing 10, and also extracts the dust inside the body; the airflow passes through the air passage between the duct housing 10 and the motor and pushes the two cover plates 31 of the one-way valve assembly 30 to close outward, and the airflow is discharged from the exhaust port of the duct housing 10; the air passing through the air passage can also cool the housing of the fan motor 20. After the fan motor 20 stops, the torsion spring of the one-way valve assembly 30 pushes the two cover plates 31 to block the exhaust port of the duct housing 10 to prevent foreign objects from entering the body interior.

[0038] The above embodiments are only illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical idea disclosed by the present invention should still be covered by the claims of the present invention.

Claims

1. A sand discharge fan for a helicopter, characterized in that Comprising: A ducted housing (10), which is cylindrical, and its internal passage (11) extends to both sides, forming an air inlet and an air outlet at the two end faces of the ducted housing (10) respectively; A fan motor (20), coaxially arranged in the internal passage; there is an air flow passage left between the outer shell of the fan motor (20) and the inner surface of the ducted housing (10), and the two are connected by fan stator vanes (21); A fan impeller (22) is installed at one end of the fan motor (20) close to the air outlet, and the fan impeller (22) is driven by the fan motor (20); A check valve assembly (30), arranged at the air outlet of the ducted housing (10), which includes two semicircular cover plates (31) and a fixed rod (32) fixedly installed in the air outlet; the cover plates (31) are rotatably connected to the fixed rod and are driven by a torsion spring (33); when the fan motor (20) stops rotating, the torsion spring drives the two cover plates (31) to cover the air outlet; when the fan motor (20) starts, the air flow generated by the fan impeller (22) pushes the two cover plates (31) to close outward, so that the air outlet is opened.

2. The sand discharge fan for a helicopter according to claim 1, characterized in that: Wear-resistant coatings are provided on the inner surface of the ducted housing, the surface of the fan motor, and the surface of the fan impeller.

3. The sand discharge fan for a helicopter according to claim 1, wherein: A plurality of connecting lugs (12) extending outward are arranged at a position of the ducted housing (10) close to the air inlet.

4. The sand discharge fan for a helicopter according to claim 1, characterized in that: The fan motor (20) is an asynchronous motor, and its internal rotor is a cast copper rotor.

5. A sand discharge fan for a helicopter according to claim 1, characterized in that: The fan impeller (22) includes an impeller disc (23) and fan blades (24); the impeller disc (23) is circular with an outer diameter larger than the outer shell of the fan motor (20), and its center is fixedly connected to the output shaft of the fan motor (20) by bolts; the fan blades (24) are fixedly arranged at the outer edge of the impeller disc (23) and extend outward.

6. The sand discharge fan for a helicopter according to claim 1, characterized in that: The fan stator vanes (21) and the housing of the fan motor (20) are of an integral structure; the outer end face of the fan stator vanes (21) abuts against the inner surface of the ducted housing (10) and is fixedly connected to the ducted housing (10) by bolts.

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