1. A hydrofoil device adaptive to a light amphibious vehicle comprises a hydrofoil assembly (1), a hinge assembly (2), a hydrofoil base (3), a connecting seat (4), a joint bearing (5), a pin shaft (6) and a connecting seat (1)^#Hydraulic cylinder (7), rotating shaft (8), rotating shaft seat (9) and 2^#A hydraulic cylinder (10); the hydrofoil assembly is characterized in that the hydrofoil assembly (1) is sequentially composed of a T-shaped framework (1 a), stringers (1 b) and skins (1 c), wherein the stringers (1 b) are sequentially assembled and welded on a preset position of the T-shaped framework (1 a), the skins (1 c) sequentially cover the surfaces of the stringers (1 b), the cross section of the hydrofoil assembly (1) is generally in the shape of a wing, the front edge of the hydrofoil assembly is in the shape of a water drop, the sweepback angle of the front edge of the hydrofoil assembly is 16 degrees, the rear edge of the hydrofoil assembly is a straight line, the adjusting range of the attack angle of the hydrofoil assembly (1) is 3-15 degrees, and the hydrofoil assembly (1) is fixedly connected with the hydrofoil base (3) through two hinge assemblies (2) in sequence through fastening bolts; a plurality of mounting holes (3 a) are formed in the rear part of the hydrofoil base (3) in order; the three connecting seats (4) are respectively and sequentially arranged in the middle of the upper surface of the hydrofoil assembly (1) and on preset positions of a rear lower cross beam (B) and a rear middle cross beam (C) of the frame assembly; the joint bearing (5) is formed by assembling a GE type bearing (5 a) and a rod end (5 b) with external threads, the inclination angle ranges from 3 degrees to 15 degrees, wherein the GE type bearing (5 a) is orderly sleeved in the connecting seat (4) positioned in the middle of the upper surface of the hydrofoil assembly (1) through the pin shaft (6), and the rod end (5 b) is connected with the connecting seat (4) through the pin shaft (6)^#The threaded holes at the lower end of the hydraulic cylinder (7) are orderly connected and assembled; 1 is described^#The upper end of the hydraulic cylinder (7) is provided with an ear ring, and the hydraulic cylinder is orderly connected and assembled with the connecting seat (4) on the rear lower cross beam (B) of the frame assembly through the pin shaft (6); one end of the rotating shaft (8) is sequentially and fixedly arranged in the middle of the hydrofoil base (3), and the other end of the rotating shaft is sequentially sleeved in the rotating shaft seat (9); the rotating shaft seat (9) Orderly welded and installed at the preset position of a rear lower side beam (A) of the frame assembly; 2 is described^#Two ends of the hydraulic cylinder (10) are respectively provided with an ear ring 2^#The earrings at the lower end of the hydraulic cylinder (10) are orderly connected and assembled with the mounting hole (3 a) at the rear part of the hydrofoil base (3) through the pin shaft (6), and the earrings at the upper end of the hydraulic cylinder are orderly connected and assembled with the connecting seat (4) on the rear middle cross beam (C) of the frame assembly through the pin shaft (6); the two sets of hydrofoil devices are orderly assembled at preset positions on two sides of the rear lower part of the vehicle body in a symmetrical mode.

2. The hydrofoil device adapted to a light amphibious vehicle according to claim 1, wherein the folding mechanism of the hydrofoil assembly (1) consists of a hinge assembly (2), a hydrofoil base (3), a connecting seat (4), a joint bearing (5), a pin shaft (6) and a pin shaft (1)^#A hydraulic cylinder (7) which is manually controlled and operated 1^#Control of hydraulic cylinder (7) and control device 1^#The hydraulic cylinder (7) extends out or retracts in order to drive the hydrofoil assembly (1) to turn over for 90 degrees upwards or downwards by taking the connecting point of the hinge assembly (2) as the center, so that the hydrofoil assembly (1) is folded or unfolded.

3. The hydrofoil device adapted to light amphibious vehicle of claim 1, wherein the "angle of attack adjustment mechanism" of hydrofoil assembly (1) is composed of hydrofoil base (3), connection seat (4), pin shaft (6), rotation shaft (8), rotation shaft seat (9) and 2^#A hydraulic cylinder (10); by manual manipulation and 2^#Control associated with the hydraulic cylinder (10) of 2^#The hydraulic cylinder (10) extends out or retracts in order to drive the hydrofoil assembly (1) to rotate upwards or downwards for 3-15 degrees by taking the rotating shaft (8) as a center, so that the required optimal attack angle (alpha) of the hydrofoil assembly (1) is obtained timely.

4. The hydrofoil device adapted to a light amphibious vehicle according to claim 1, characterized in that for amphibious special vehicle without adjusting the angle of attack (α), the hydrofoil assembly (1) can be assembled directly on the preset position of the lower side beam (a) behind the frame assembly through two said hinge assemblies (2) via fastening bolts.

Background

The water surface running speed of the amphibious vehicle is an important index for measuring the comprehensive performance of the amphibious vehicle; the first factor influencing the water surface speed per hour of the amphibious vehicle is the so-called 'shape resistance' caused by the volume and shape of the vehicle body immersed in water; researches and experiments prove that the basic principles of 'water drift principle', 'potential flow theory' and 'viscous fluid mechanics' are scientifically applied, a 'hydrofoil device' capable of continuously generating water lift power is arranged for the amphibious vehicle, and the method is the most economical and effective scientific method for remarkably improving the water surface speed per hour of the amphibious vehicle on the premise of not increasing the power of an engine.

Hydrofoils are now widely used in the ship industry for rudders, paddles, stabilizer fins, submarine and mine fin wings, missile stabilizer rings, water jet propeller blades, etc., and play a very important role in the ship industry, particularly in the development of high-speed hydrofoils, novel propulsion wings and control wings for ships; at present, the research on the hydrofoil is deepened day by day, the method is advanced day by day, and the water lift dynamic performance of the hydrofoil can be accurately forecasted by applying the potential flow theory; on the basis, the FLUENT software is applied to simulate and observe the surrounding flow field of the hydrofoil when the hydrofoil has an attack angle; the hydrodynamic performance of the hydrofoil can be further subjected to detailed computational analysis by using a computational formula of viscous fluid mechanics.

The patent number ZL201010158215.8 is named as an invention patent of an amphibious vehicle folding hydrofoil device, and the disclosed technical scheme is as follows: the device is a 6-rod mechanism with the degree of freedom of 1, and is additionally arranged on two sides of a vehicle body of a crawler-type amphibious vehicle, when the amphibious vehicle sails in water, a hydrofoil device is unfolded under the driving of a hydraulic cylinder, and a flat plate connected to a folding mechanism is used as a hydrofoil to increase the water-facing area of the amphibious vehicle when the amphibious vehicle sails in water, so that the amphibious vehicle rises from the water as soon as possible, and the purposes of reducing water resistance and improving the sailing speed are indirectly achieved; when the amphibious vehicle runs on the land, the hydraulic cylinder retracts, the folding mechanism is folded, and the flat plate is in a vertical state parallel to the side edge of the vehicle body; the folding mechanism comprises a first hydraulic cylinder 1, a first reinforcing cross beam 2, a first hydraulic cylinder cylindrical pin 3, a hydrofoil flat plate 4, a first vertical rod 5, a first connecting bolt 6, a first slider lower cylindrical pin 7, a first slider 8, a second reinforcing cross beam 9, a second connecting bolt 10, a second vertical rod 11, a third connecting bolt 12, a second slider lower cylindrical pin 13, a third reinforcing cross beam 14, a second slider 15, a third vertical rod 16, a second hydraulic cylinder cylindrical pin 17, a fourth reinforcing cross beam 18, a second hydraulic cylinder 19, a fourth vertical column 20, a third long slider cylindrical pin 21, a third long slider 22, a third fixed slot slider 23, a connecting cross rod 24, a second connecting rod 25, a second slider upper cylindrical pin 26, a second long slider cylindrical pin 27, a second long slider 28, a second fixed slider slot 29, a first connecting rod 30, a first long slider cylindrical pin 31, a first long slider 32, a first fixed slider slot 33, the first slide block comprises a cylindrical pin 34, a first upright post 35, a crawler belt 36, a vehicle body 37, a second upright post 38, a third upright post 39 and the like.

The patent No. ZL201010248926.4 is named as an invention patent of a folding hydrofoil device for avoiding a crawler-type amphibious vehicle action system, and the technical scheme is as follows: when the amphibious vehicle sails in water, the hydrofoil device is unfolded under the driving of the hydraulic cylinder, and the flat plate connected to the folding mechanism is used as the hydrofoil, so that the water-facing area of the amphibious vehicle during sailing in water is increased, the lift force borne by the amphibious vehicle is improved, the amphibious vehicle is lifted from the water as soon as possible, and the purposes of reducing the resistance borne by the amphibious vehicle and improving the sailing speed are indirectly achieved; when the amphibious vehicle runs on land, the hydraulic cylinder retracts, the folding mechanism is retracted under the auxiliary action of the spring, and the flat plate is in a vertical state parallel to the side edge of the vehicle body; the folding mechanism comprises a flat plate 4, a first upright column 32, a second upright column 31, a third upright column 29, a fourth upright column 16, a first reinforcing cross beam 2, a second reinforcing cross beam 9, a third reinforcing cross beam 14, a fourth reinforcing cross beam 19, a first hydraulic cylinder 1, a second hydraulic cylinder 20, a first sliding block 8, a second sliding block 30, a first vertical rod 5, a second vertical rod 11, a third vertical rod 15, a first long sliding block 58, a second long sliding block 47, a third long sliding block 24, a first steel wire rope 35, a second steel wire rope 44, a third steel wire rope 21, a first pulley 36, a second pulley 53, a third pulley 40, a first spring 56, a second spring 49, a third spring 41 and the like.

The invention relates to a water wing device, in particular to a water wing device, which is characterized in that a flat plate is used as a hydrofoil, a hydrofoil plate and a folding mechanism thereof are shown in the two invention patents, the structure is complicated and original, the parts are various and heavy, the flat plate or the hydrofoil plate can only be longitudinally assembled, and the ' water float principle ' and a theoretical formula for calculating the water wing water lift power ' can be known.

The invention discloses an invention patent with application number 202011383462.8 named as 'an adjustable T-shaped hydrofoil stealth composite ship and a control method thereof', and the technical scheme is as follows: the device comprises a ship body, a working box, a lifting device and a hydrofoil piece; the hydrofoil part is connected with the other end of the transmission shaft assembly, is arranged outside the working box, and further comprises an up-down rotating device for completing up-down rotation of the wing, and the water penetration depth of the wing is adjusted through a cylinder; the invention aims to solve the defect of poor stability of the traditional inward-inclined stealth ship and improve the stability of the inward-inclined ship by installing the adjustable T-shaped wing below a keel of the bow of the stealth single ship and enabling the hydrofoil to be positioned at different positions under different navigation conditions of the ship by rotating the hydrofoil and lifting the hydrofoil.

The invention patent with application number 202011415925.4, named as 'an electric hydrofoil', discloses the technical scheme as follows: the electric hydrofoil comprises a surfboard, a propeller component, a mast and an electronic speed regulation device, wherein the surfboard and the hydrofoil are respectively arranged at two ends of the mast; the invention aims to provide an electric hydrofoil, which is used for solving the technical problems that in the prior art, the size of an electronic speed regulating device arranged at the bottom of the electric hydrofoil is limited, the electronic speed regulating device is inconvenient to install and the requirement on waterproof sealing performance is high.

The invention patent with application number 202011333034.4 and named as 'a hydrofoil' discloses the technical scheme as follows: the bottom surface of the hydrofoil is provided with a groove structure which is used for reducing the flow velocity when water flows through the bottom surface; the bottom surface of the hydrofoil is provided with the groove structure, so that the flow speed of water flow passing through the bottom surface of the hydrofoil is reduced, the pressure of the bottom surface of the hydrofoil is improved, the pressure difference between the bottom surface of the hydrofoil and the upper surface of the hydrofoil is increased, and the lift force of the hydrofoil is improved; the aim of the invention is to improve the efficiency of the hydrofoil while controlling the cost.

The invention patent of application number 201910653648.1, named as 'foldable hydrofoil craft', discloses the technical scheme as follows: the submarine comprises a submarine body and at least one hydrofoil propelling mechanism connected with the submarine body; the hydrofoil propelling mechanism comprises a support frame, a folding arm component, a driving component and a hydrofoil propelling component; the support frame is arranged on the boat body; the two sides of the boat body are respectively provided with a hydrofoil propelling component which is movably connected with the support frame through a folding arm component; the driving assembly is respectively movably connected with the support frame and the folding arm assembly and is used for adjusting the unfolding angle of the folding arm assembly relative to the horizontal plane; the unfolding angle of the folding arm component relative to the horizontal plane is adjusted through the driving component, so that the angle of the hydrofoil propelling component relative to the horizontal plane is adjusted, and the driving stability and safety are guaranteed; the invention aims to realize the adjustment of the angle of the hydrofoil propelling component relative to the horizontal plane in the advancing process and guarantee the driving stability and safety.

The invention discloses an invention patent with application number 201510312468.9 named as 'a T-shaped hydrofoil and rotor wing composite stabilizer', which discloses the technical scheme as follows: the T-shaped hydrofoil and rotor wing composite stabilizer consists of a strut, a horizontal main wing, a flap and a rotor wing, wherein the upper end of the strut 1 is fixed at the bottom of a ship, the lower end of the strut is vertically connected with the horizontal main wing 2, the rotor wing 3 is of a cylindrical structure, is positioned in an aileron cabin in the horizontal main wing and is driven by a hydraulic oil cylinder and a motor; the invention aims to improve the wave resistance and the seaworthiness of a high-speed ship at low speed and reduce the discomfort of passengers.

The invention patent of 'an amphibious unmanned transporter based on hydrofoil technology' is applied to the patent number 202011555883.4, and the technical scheme is as follows: the water-tight buoyancy tank is arranged at the lower half part of the fuselage, the wing is a hydrofoil type wing with a downward turning function at the outer side, and the tail wing adopts a T-shaped tail wing structure; the aircraft further comprises a wing layout structure, an inner side wing structure, an outer side downward-reversed hydrofoil structure, an airframe structure, an empennage structure and a take-off and landing system; the invention aims to balance the airplane by adopting the arrangement of the single-wing type airplane with the outer wing capable of turning down and turning down, and utilizing the hydrodynamic lift force generated by the turning-down outer wing of the hydrofoil type airplane, and reduce the immersion volume of the airplane body, so that the hydrodynamic resistance of the airplane is obviously reduced during takeoff, and the required maximum thrust is reduced.

The technical schemes disclosed by the invention patents do not relate to the internal structure of the hydrofoil, and do not refer to the condition that a proper attack angle is preset for the hydrofoil; and the advanced technical scheme that the hydrofoil can be folded by upwards turning for 90 degrees and can also be used for timely adjusting the attack angle by longitudinally rotating is not involved.

Disclosure of Invention

According to the theory of potential flow and viscous hydrodynamics, the water lift force (C) generated by the hydrofoil_L) The following can be obtained by means of the general formula: "C_L=L / (1/2) ρV²S' calculating; where rhoIs the incoming flow density, V is the incoming flow velocity, S is the hydrofoil plane area, C_LIs the lift coefficient. The lift characteristic is also referred to as the characteristic of the lift coefficient, which affects the lift coefficient (C)_L) The factors include the angle of attack alpha of incoming flow, Reynolds number Re of incoming flow, chord Froude number Fr and immersion Froude number of hydrofoil (which can not be considered when the water surface wave is not considered), the chord length Lambda of wing, and sweep angle alpha_LAirfoil type, camber to thickness ratio, and the like. The typical lift characteristic is usually represented by a relationship curve (called lift curve) of the lift coefficient to the angle of attack alpha.

According to "potential flow theory" and "viscous fluid mechanics", the drag (D) generated by the hydrofoil can also be determined by means of the general formula: "C_D=D / (1/2) ρV²S' calculating; in the formula C_DIs the coefficient of resistance. When wave-making resistance is not included, the typical resistance characteristic is also represented by a resistance coefficient C_DAnd the relation with the attack angle alpha is shown. Wherein C is_DIncluding coefficient of viscous drag C_doAnd coefficient of induced resistance C_di。

The hydrofoil assembly 1 of the present invention is obtained through extensive research and simulation tests.

(1) The stall angle of the hydrofoil is 15 degrees, and before the attack angle alpha of 15 degrees, the lift coefficient of the hydrofoil increases gradually along with the increase of the attack angle alpha and is approximately in a linear change relationship; after an angle of attack α of 15 degrees, the lift coefficient decreases with increasing angle of attack α and changes at a rate less than before 15 degrees.

(2) Within a certain range, the resistance coefficient increases with the increase of the attack angle alpha, the change rate also increases continuously, and the resistance also increases. Therefore, in order to obtain better lift-drag performance, attention should be paid to not too large drag while selecting the attack angle α to satisfy the lift.

(3) From the pressure profile of the hydrofoil it can be found that: the leading edge pressure of the hydrofoil is greater than the trailing edge, which is the main reason for the hydrofoil drag; as the angle of attack α increases, a positive pressure region occurs near and below the leading edge of the hydrofoil and a negative pressure region occurs at the upper surface of the hydrofoil, resulting in a pressure differential between the upper and lower surfaces of the hydrofoil, thereby causing the hydrofoil to generate a water lift force.

The invention aims to provide a novel structure which has the advantages of compact structure, reliable performance, convenient assembly and disassembly and obvious effect; three functions and functions of greatly shortening the water surface skidding time of the amphibious vehicle, continuously generating water lifting power, reducing water resistance, obviously improving the comfort performance of the amphibious vehicle when the amphibious vehicle runs in wind waves and the like; can be folded at 90 degrees and arranged at two sides of the rear part of the vehicle body; the adjustment of the attack angle of the hydrofoil can be realized timely and flexibly; the hydrofoil device can be matched with light amphibious vehicles of various models.

The technical problems to be actually solved by the invention are as follows: how to realize the specific functions, folding, retracting and angle of attack adjustment of the hydrofoil assembly.

The invention adopts the following technical scheme to achieve the purpose of the invention.

A hydrofoil device adaptive to a light amphibious vehicle comprises a hydrofoil assembly 1, a hinge assembly 2, a hydrofoil base 3, a connecting seat 4, a joint bearing 5, pin shafts 6 and 1^#Hydraulic cylinder 7, rotary shaft 8, rotary shaft seat 9 and 2^#A hydraulic cylinder 10.

The hydrofoil assembly 1 which is optimized by SIMPLE9 through system research and scientific design has the following technical characteristics.

The main structure of the hydrofoil assembly 1: the hydrofoil assembly 1 is sequentially composed of a T-shaped framework 1a, stringers 1b and a skin 1c, wherein the stringers 1b are sequentially assembled and welded on a preset position of the T-shaped framework 1 a; the skin 1c is in turn wrapped over the surface of the stringer(s) 1 b.

Geometrical features of the hydrofoil assembly 1: the cross section of the hydrofoil assembly 1 is in a wing shape, wherein the front edge is in a water drop shape, the rear edge is in a tile shape, and a high water lift dynamic effect can be continuously generated.

Layout design of the hydrofoil assembly 1: (unilateral) hydrofoil area of 0.45m²Aspect ratio of 1.07, span of 0.7m, and sweep angle of leading edge of 16⁰The trailing edge is a straight line, the torsion angle is-3.5 degrees, and the upturning angle in folding is 90 degrees⁰The adjusting range of the attack angle (alpha) of the hydrofoil assembly 1 is 3 to 15⁰。

Performance of hydrofoil assembly 1Indexes are as follows: the hydrofoil load is 2670 kg/m²Wing weight 2400kg (structure weight 1900kg, fuel weight 200kg, load 300 kg)

The hydrofoil assembly 1 is fixedly connected with the hydrofoil base 3 in order through a hinge assembly (two hinge assemblies) 2 and a fastening bolt.

The rear part of the hydrofoil base 3 is orderly provided with (a plurality of) mounting holes 3 a.

The (three) connecting seats 4 are respectively and orderly arranged in the middle of the upper surface of the hydrofoil assembly 1 and the preset positions of the rear lower cross beam B and the rear middle cross beam C of the frame assembly.

The knuckle bearing 5 is assembled by a GE type bearing 5a and a rod end 5b with external threads, and the inclination angle ranges from 3 degrees to 15 degrees; wherein the GE type bearing 5a is orderly sleeved in the connecting seat 4 positioned in the middle of the upper surface of the hydrofoil assembly 1 by the pin shaft 6, and the rod end 5b is sleeved in the connecting seat 4 positioned in the middle of the upper surface of the hydrofoil assembly 1 by the pin shafts 6 and 1^#The threaded holes at the lower end of the hydraulic cylinder 7 are orderly connected and assembled.

1^#The upper end of the hydraulic cylinder 7 is provided with an ear ring, and the pin shaft 6 is connected and assembled with the connecting seat 4 on the rear lower beam B of the frame assembly in order.

One end of the rotating shaft 8 is orderly arranged in the middle of the hydrofoil base 3, and the other end is orderly sleeved in the rotating shaft seat 9.

The rotating shaft seat 9 is orderly welded and installed on a preset position of a rear lower side beam A of the frame assembly.

2^#The two ends of the hydraulic cylinder 10 are provided with earrings 2^#The earrings at the lower end of the hydraulic cylinder 10 and the mounting holes 3a at the rear parts of the pin shaft 6 and the hydrofoil base 3 are orderly connected and assembled, and the earrings at the upper end of the hydraulic cylinder are orderly connected and assembled with the connecting seats 4 on the rear middle cross beam C of the frame assembly through the pin shaft 6.

For some amphibious special vehicles without adjusting the attack angle (alpha), the hydrofoil assembly 1 can also be directly assembled on a preset position of a lower side beam A behind the vehicle frame assembly through two hinge assemblies 2 and fastening bolts.

The invention consists of two sets of hydrofoil devices which are arranged as above and are orderly assembled at preset positions on two sides of the rear lower part of the vehicle body in a symmetrical mode.

The working principle of the invention is as follows: by artificial manipulation of the phasesThe corresponding oil cylinder controller can lead 1^#The hydraulic cylinder 7 extends or retracts to drive the hydrofoil assembly 1 to turn over for 90 degrees upwards or downwards by taking the connecting point of the hinge assembly 2 as the center, so that the hydrofoil assembly 1 is folded or unfolded, and therefore, after the amphibious vehicle is assembled with the amphibious vehicle, the land driving performance of the vehicle is not influenced at all.

Similarly, by manually operating the corresponding cylinder controller, 2 can be controlled^#The hydraulic cylinder 10 extends or retracts to drive the hydrofoil assembly 1 to rotate upwards or downwards by 3-15 degrees by taking the rotating shaft 8 as a center, so that the required optimal attack angle (alpha) of the hydrofoil assembly (1) is obtained timely.

When the amphibious vehicle provided with the hydrofoil device runs on the water surface, a proper attack angle (alpha) is set for the hydrofoil assembly 1 in advance, so that once the hydrofoil assembly 1 is opened, the water surface skidding time of the amphibious vehicle can be greatly shortened; after the amphibious vehicle enters a high-speed operation stage, because the cross section of the hydrofoil assembly 1 is designed into a wing shape, water flows flowing through the upper surface and the lower surface of the hydrofoil form pressure difference, so that water lift power can be continuously generated to support most of the bottom of the hull out of the water surface, water resistance can be obviously reduced, and the water surface operation speed per hour of the amphibious vehicle can be improved; in addition, the hydrofoil assembly 1 is immersed into the water surface deeply, so that the running stability of the amphibious vehicle on the water surface can be improved, and most of the bottom of the amphibious vehicle leaves the water surface at the moment, so that impact and beating of sea wave splash on the vehicle are small, and the driving comfort is improved and improved remarkably.

The technical problems to be actually solved by the present invention are as follows.

(1) Sequentially assembling, welding, coating and processing the T-shaped framework 1a, the stringer 1b and the skin 1c into the hydrofoil assembly 1; the cross section of the hydrofoil assembly 1 is designed into a wing shape, so that water flow flowing through the upper surface and the lower surface of the hydrofoil forms pressure difference, water lift power can be continuously generated, and water resistance of the amphibious vehicle during water surface running is remarkably reduced.

(2) Comprises a hinge assembly 2, a hydrofoil base 3, a connecting seat 4, a joint bearing 5, pin shafts 6 and 1^#The hydraulic cylinder 7 forms a folding mechanism of the hydrofoil assembly 1; by manual manipulation with 1^#Control of hydraulic cylinder 7, 1^#The hydraulic cylinder 7 extends or retracts in order to realize the expansion or folding of the hydrofoil assembly 1.

(3) Comprises a hydrofoil base 3, a connecting seat 4, a pin shaft 6, a rotating shaft 8, rotating shaft seats 9 and 2^#The hydraulic cylinder 10 forms an attack angle adjusting mechanism of the hydrofoil assembly 1; by manual manipulation and 2^#Control associated with hydraulic cylinder 10, 2^#The hydraulic cylinder 10 extends out or retracts in sequence, so that the attack angle (alpha) of the hydrofoil assembly 1 is timely adjusted, water lifting power is generated as soon as possible, and the water surface skidding time of the amphibious vehicle is shortened.

(4) The underwater depth of the hydrofoil assembly 1 is increased as much as possible, and the water lift power of the hydrofoil assembly 1 is continuously improved; the vibration of the vehicle caused by the waves is obviously reduced, and the comfort performance of the driver is improved and provided.

Due to the adoption of the technical scheme, the invention perfectly achieves the aim.

After the amphibious vehicle is assembled with the invention, the water surface skidding time can be greatly shortened; can continuously generate water-lifting power; the comfort of the operation in wind and wave can be obviously improved; compared with similar products, the product has the following outstanding advantages, namely the beneficial effect.

1. Scientific design, advanced structure, reliable performance and obvious resistance and speed increasing effects.

2. The standardization degree of the parts is high, the manufacturing technology is advanced, and the parts are easy to assemble, disassemble and maintain.

3. Can be conveniently matched with various light amphibious vehicles, and has wide application range.

Drawings

The invention is further described below with reference to the given figures.

Fig. 1 is a schematic view of the main structure of the present invention.

Fig. 2 is a schematic view of the folded state of the present invention.

Fig. 3 is a schematic view of the open state of the present invention.

Fig. 4 is a schematic view of the present invention mounted directly on the rear lower side member a.

Detailed Description

As can be seen from FIGS. 1, 2 and 3, the present inventionComprises a hydrofoil assembly 1, a hinge assembly 2, a hydrofoil base 3, a connecting seat 4, a joint bearing 5, pin shafts 6 and 1^#Hydraulic cylinder 7, rotary shaft 8, rotary shaft seat 9 and 2^#The hydraulic cylinder 10 has the obvious technical characteristics of scientific design, advanced structure, reliable performance and the like.

As also shown in fig. 1, 2 and 3, in order to enable the hydrofoil assembly 1 to continuously generate water-lift power, the cross section of the hydrofoil assembly is designed to be wing-shaped; at the moment, the flow velocity of water flow passing through the bottom surface of the hydrofoil is small, and the pressure on the bottom surface of the hydrofoil is increased, so that a pressure difference is formed between the upper surface and the lower surface of the hydrofoil, and the hydrofoil can continuously generate water lift power; by means of the hydrodynamic lift force generated by the hydrofoil assembly 1, the amphibious vehicle can lift the vehicle body originally immersed in water out of the water surface at a low speed, so that the immersion area of the vehicle in water can be reduced rapidly, and the water resistance can be reduced.

As further shown in fig. 1, 2 and 3, in order to significantly improve the driving comfort during operation on water, the pivot seat 9 is welded to a predetermined position of the rear lower side member a of the frame assembly in order to immerse the hydrofoil assembly 1 as far as possible into the water through the pivot 8, the hydrofoil base 3 and the hinge assembly 2.

Practice proves that: coefficient of lift (C) of hydrofoil assembly 1_L) Closely related to the depth of immersion of the hydrofoil assembly 1 under water. When the upper surface of the hydrofoil assembly 1 is not underwater, the hydrofoil assembly is in a sliding state, and the lift coefficient (C) of the hydrofoil assembly 1 in the sliding state_L) Only 50% of the total immersion state exists, which greatly reduces the function of the hydrofoil assembly 1; in addition, because the underwater depth of the hydrofoil assembly 1 is very small, the vehicle vibrates greatly when the sea wave is large, and the comfort of drivers and passengers is greatly reduced.

As further shown in fig. 1, 2 and 3, in order to adapt to and satisfy the adjustment of the attack angle (α) of the hydrofoil assembly 1, a joint bearing 5 is installed in a connecting seat 4 on the surface of the hydrofoil assembly 1, and a joint bearing 2 is installed at the rear end of a hydrofoil base 3^#A hydraulic cylinder 10.

The method is known through deep research and simulation experiments.

(1) Before the attack angle of 15 degrees, the lift coefficient of the hydrofoil increases along with the increase of the attack angle (alpha) and is approximately in a linear change relationship; after an angle of attack of 15 degrees, the lift coefficient decreases with increasing angle of attack, and the rate of change is less than the rate of change before 15 degrees, which is generally called as angle of loss spouse, and the lift coefficient at stall angle is the maximum lift coefficient (i.e. the maximum possible gain of lift); at about-1.5 degrees, the lift coefficient is zero, and typically this angle of attack is zero, representing the lift onset angle.

(2) The drag coefficient increases with increasing angle of attack (α) and the rate of change also increases. Therefore, in a certain range, the lift force is gradually increased along with the increase of the attack angle, but the resistance is increased along with the increase of the attack angle, so that when the attack angle is selected, the resistance is not too large while the lift force is satisfied, in order to obtain good lift-drag performance. As the angle of attack increases, the lift-to-drag ratio L/D increases gradually, with the slope of the curve increasing and thereafter reaching a peak, and as the angle of attack (α) continues to increase, the lift-to-drag ratio decreases. This indicates that the hydrofoil has an optimum angle of attack (α) where the lift of the hydrofoil is at its maximum and the drag is at its minimum.

(3) When the angle of attack (α) is at 0 degrees, the streamlines flow smoothly along the hydrofoil surface, after which the streamlines gradually leave the surface of the hydrofoil as the angle of attack (α) increases, while the streamlines at the trailing edge of the hydrofoil gradually converge into three parts: namely, the upper wing end, the lower wing end and the middle part of the wing, if the attack angle (alpha) is increased, the separation phenomenon of the streamline on the surface of the hydrofoil is more serious, and meanwhile, the middle streamline of the tail edge of the hydrofoil is gradually gathered towards the two ends, the middle streamline disappears, and only the streamlines at the two ends of the hydrofoil are left.

By manual manipulation and 2^#Control associated with hydraulic cylinder 10, 2^#The hydraulic cylinder 10 extends or retracts in sequence to realize the timely adjustment of the attack angle (alpha) of the hydrofoil assembly 1; the purpose of adjusting the attack angle (alpha) of the hydrofoil assembly 1 is to generate water lifting power as soon as possible and shorten the water surface skidding time of the amphibious vehicle.

As further shown in fig. 1, 2 and 3, in order to better satisfy the passing performance required for land driving of the amphibious vehicle, the upturning angle of the hydrofoil assembly 1 is designed to be 90⁰。

As can be seen from fig. 4, the hydrofoil assembly 1 can also be directly assembled on the preset position of the lower side beam a behind the frame assembly through two hinge assemblies 2 via fastening bolts.