阅读说明：本技术 一种应用磁力联轴器的对转桨海流能发电装置 (Counter-rotating propeller ocean current energy power generation device applying magnetic coupling ) 是由 黄滨 王超 龚寅晨 王鹏忠 赵博文 于 2021-08-30 设计创作，主要内容包括：本发明公开一种应用磁力联轴器的对转桨海流能发电装置,其包括壳体、对转叶轮、转向和偏航装置、磁力联轴装置、机械变速装置和发电机装置；对转式叶轮安装在发电装置的前端,叶片在来流冲击下绕中心轴转动,并产生驱动转轴转动的切向力,两组叶片分别通过内、外轴将扭矩传递到磁力联轴器输入端。磁力联轴器通过异极排列的永磁体推拉的耦合传动方式,使用轴向联轴器和径向联轴器的组合,实现非接触式将对转轴的扭矩由发电装置外部传递到发电装置内部。机械变速装置将对转扭矩进行力矩耦合,实现单轴输出并用齿轮机构进行变速。发电机内转子与机械变速装置连接并随其转动,与外定子实现切割磁感线运动进行发电。本发明结构紧凑,动能转化率高。(The invention discloses a contra-rotating propeller ocean current energy power generation device applying a magnetic coupling, which comprises a shell, a contra-rotating impeller, a steering and yawing device, a magnetic coupling device, a mechanical speed change device and a power generator device, wherein the contra-rotating impeller is arranged on the shell; the contra-rotating impeller is arranged at the front end of the generating set, the blades rotate around the central shaft under the impact of incoming flow and generate tangential force for driving the rotating shaft to rotate, and the two groups of blades transmit torque to the input end of the magnetic coupling through the inner shaft and the outer shaft respectively. The magnetic coupling realizes that the torque of the counter shaft is transmitted to the inside of the power generation device from the outside of the power generation device in a non-contact manner by using the combination of the axial coupling and the radial coupling through a coupling transmission mode of pushing and pulling permanent magnets arranged in different poles. The mechanical speed change device carries out torque coupling on the rotating torque, realizes single-shaft output and carries out speed change by using a gear mechanism. The inner rotor of the generator is connected with the mechanical speed change device and rotates along with the mechanical speed change device, and the inner rotor and the outer stator realize cutting magnetic induction line motion to generate electricity. The invention has compact structure and high kinetic energy conversion rate.)

1. A contra-rotating propeller ocean current energy power generation device applying a magnetic coupling is characterized by comprising a shell, contra-rotating impellers positioned outside the shell, a steering and yawing device, a mechanical speed change device and a generator device positioned inside the shell, and a magnetic coupling device for transmitting torque;

the shell comprises a flow guide shell (4), a connecting shell (5), a middle shell (6) and a rear shell (7) which are sequentially connected from front to back;

the contra-rotating impeller comprises a sleeved blade outer shaft (12), a sleeved blade inner shaft (13), a front blade group (2) and a rear blade group (3) which are coaxially arranged and have opposite rotating directions; the front blade group (2) is fixedly sleeved on the blade inner shaft (13), and the rear blade group (3) is fixedly sleeved on the blade outer shaft (12); the front blade group (2) rotates to drive the inner blade shaft (13) to rotate, and the rear blade group (3) rotates to drive the outer blade shaft (12) to rotate;

the magnetic coupling device comprises an axial transmission mechanism and a radial transmission mechanism;

the axial transmission mechanism comprises an axial coupler input shaft (15), an axial coupler input rotor (17), an axial coupler output rotor (19) and an axial coupler output shaft (21); the radial transmission mechanism comprises a radial coupling input shaft (14), a radial coupling inner rotor (16), a radial coupling outer rotor (18) and a radial coupling output shaft (20); one end of the axial coupling input shaft (15) is connected with the inner blade shaft (13), the outside of the axial coupling input shaft is sleeved by the radial coupling input shaft (14), and the radial coupling input shaft (14) is fixedly connected with the outer blade shaft (12); the inner rotor (16) of the radial coupling is fixedly sleeved on the periphery of the input shaft (14) of the radial coupling, one end of the outer rotor (18) of the radial coupling is sleeved on the periphery of the inner rotor (16) of the radial coupling, the outer rotor (18) of the radial coupling is of a sleeve type structure, and two ends of the outer rotor (18) of the radial coupling are supported in the middle shell (6) through bearings; mounting grooves are formed in the positions, corresponding to the inner periphery of the radial coupling outer rotor (18), of the outer periphery of the radial coupling inner rotor (16), and permanent magnets (37) which are symmetrically distributed, fan-shaped and different in polar direction are embedded in the mounting grooves; a radial coupling output shaft (20) is fixedly sleeved inside the other end of the radial coupling outer rotor (18); a through hole is formed in the output shaft (20) of the radial coupler; the other end of the axial coupling input shaft (15) is fixedly sleeved with an axial coupling input rotor (17); the axial coupling output shaft (21) and the axial coupling input shaft (15) are arranged oppositely along the radial direction of the whole power generation device and are coaxial; the axial coupler output rotor (19) and the axial coupler input rotor (17) are oppositely arranged, opposite surfaces of the axial coupler output rotor and the axial coupler input rotor are respectively provided with a groove, and permanent magnets (37) which are symmetrically distributed, fan-shaped and different in polar direction are arranged in the grooves; the axial coupler output shaft (21) is sleeved in the through hole of the radial coupler output shaft (20);

the blade outer rotor (12) drives the radial coupling input shaft (14) and the radial coupling inner rotor (16) to rotate, and then drives the radial coupling outer rotor (18) and the radial coupling output shaft (20) to rotate through magnetic coupling; the inner blade shaft (13) drives an axial coupling input shaft (15) and an axial coupling input rotor (17) to rotate, and then drives an axial coupling output rotor (19) and an axial coupling output shaft (21) to rotate through magnetic coupling;

the mechanical speed changing device comprises a moment coupling device consisting of a first bevel gear (36), a second bevel gear (35), a third bevel gear (32), a central shaft (33) and a bearing seat (34) and a speed increasing device consisting of a first gear (22), a second gear (30), a third gear (29), a fourth gear (23), a speed increasing shaft (28), a first bearing seat (31) and a second bearing seat (27); the central shaft (33) is coaxially and fixedly connected with the axial coupling output shaft (21), a first bevel gear (36) is fixedly sleeved between the axial coupling output shaft (21) and the radial coupling output shaft (20), and a second bevel gear (35) is fixedly sleeved at the end part of the central shaft (33); the second bevel gear (35) is respectively meshed with the first bevel gear (36) and the third bevel gear (32), the central axis of the second bevel gear (35) is perpendicular to the central axis, the second bevel gear (35) is connected with a bearing seat (34) through a bearing, and the bearing seat (34) supports the inner wall of the middle shell (6); the torque of the output shaft (21) of the axial coupling directly acts on the central shaft (33), and the torque of the output shaft (20) of the radial coupling acts on the central shaft (33) through the bevel gear to realize torque coupling;

the first gear (22) is fixedly sleeved on a central shaft (33) of the torque coupling device, the second gear (30) and the third gear (29) are fixedly sleeved on a speed increasing shaft (28), two ends of the speed increasing shaft (28) are supported on a first bearing seat (31) and a second bearing seat (27), the first bearing seat (31) and the second bearing seat (27) are distributed on one side of the central shaft (33) in parallel, and the fourth gear (23) is fixedly connected with the motor shaft (24). Wherein the first gear (22) is meshed with the second gear (30), and the third gear (29) is meshed with the fourth gear (23);

the generator device is positioned in the rear shell (7), the mechanical speed changing device drives a generator rotor to rotate, and induced electromotive potential energy is generated by cutting a magnetic induction line, so that mechanical energy is converted into electric energy.

2. The magnetically coupled transor marine current energy generation device of claim 1, wherein said steering and yawing means comprises a convective tail rudder and a steering means consisting of a strut (11), a platform bearing housing (10), a device platform (9); the convection tail rudder (8) is fixedly connected to the tail part of the rear shell (7), and the adjusting device passively drifts to realize the incident flow and generate electricity; the device platform (9) is fixed below the shell, the platform bearing seat (10) is fixed on the support column (11), and the device platform (9) is rotatably supported on the support column (11) through a bearing.

3. The magnetically coupled counter-rotating propeller ocean current energy generating device according to claim 1, wherein the front blade set (2) is of a three-blade structure and the rear blade set (3) is of a four-blade structure, and the rotation directions of the front blade set (2) and the rear blade set (3) are opposite in operation.

4. A magnetically coupled transor ocean current energy generation device according to claim 1 further comprising a nacelle (1), wherein said nacelle (1) is arcuate and is fixed in front of said front set of blades (2).

5. A magnetic coupling-based contra-rotating propeller ocean current energy power generation device according to claim 1, wherein the middle housing (6) comprises an outer housing and an inner housing nested inside the outer housing, and the ends of the outer housing and the inner housing are connected, and the ends of the inner housing are sealed, so that after the middle housing (6) and the rear housing (7) are connected, a sealed cavity is formed inside; the radial coupling outer rotor (18), the radial coupling output shaft (20), the axial coupling output rotor (19), the axial coupling output shaft (21), the mechanical speed changing device and the generator device are all located in the sealed cavity.

Technical Field

The invention belongs to the field of ocean current energy power generation, and particularly relates to a contra-rotating propeller ocean current energy power generation device applying a magnetic coupling.

Background

Energy is a key factor of human social development, fossil energy belongs to non-renewable energy, and in order to realize sustainable development of human society, countries in the world are paid attention to development and utilization of renewable energy, and ocean current energy is one of the renewable energy. The ocean current energy utilizes the kinetic energy of the seawater directional flow, and has the characteristics of strong predictability, high energy density, cleanness, reproducibility and small influence by wind waves. Meanwhile, ocean current energy reserves in China are abundant, and the development and utilization potentials of the ocean current energy reserves are huge. If the ocean current kinetic energy is converted into the electric energy in the submarine observation network, the power utilization requirements that the low flow rate has good starting performance and high kinetic energy conversion rate and high reliability are met, the problem of self-sufficiency of the electric energy of the submarine observation network is solved, and the underwater working efficiency and time are improved.

A contra-rotating horizontal shaft ocean current energy generator is a device for converting ocean current energy into electric energy, and adopts contra-rotating blades to generate electricity. The existing horizontal shaft ocean current energy generator is mostly in a one-way or two-way power generation technology, is sealed by a sealing ring, and has the disadvantages of low adaptability to complex sea conditions, low power generation efficiency, high sealing loss and low reliability.

The traditional coupler is widely applied as a common connecting device in a current energy power generation system, and the traditional coupler adopting a mechanical type is used for transmitting torque through mechanical coupling, so that the capability of isolating vibration in operation is relatively weak, the structure of a contra-rotating machine is complex, and the sealing is difficult. The magnetic transmission coupler transmits torque by utilizing the interaction between magnetic fields, belongs to non-contact transmission, has the characteristics of vibration isolation, noise isolation, strong compensation capability on shaft system deviation and no maintenance, and is suitable for the condition needing isolation and sealing. However, conventional magnetic couplings tend to transmit only a single shaft of torque.

Disclosure of Invention

Aiming at the problems that the existing ocean current energy power generation device cannot adapt to complex sea conditions, has low energy conversion efficiency and large sealing loss, and the problems that a coupler has a complex structure and is difficult to seal in the torque transmission process, the invention provides a contra-rotating propeller ocean current energy power generation device which adopts a permanent magnet and realizes the transmission of rotating force in a magnetic coupling transmission mode.

The purpose of the invention is realized by the following technical scheme:

a contra-rotating propeller ocean current energy power generation device applying a magnetic coupling comprises a shell, contra-rotating impellers outside the shell, a steering and yawing device, a mechanical speed changing device and a power generator device inside the shell, and a magnetic coupling device for transmitting torque;

the shell comprises a flow guide shell, a connecting shell, a middle shell and a rear shell which are sequentially connected from front to back;

the contra-rotating impeller comprises a sleeved blade outer shaft, a sleeved blade inner shaft, a front blade group and a rear blade group which are coaxially arranged and have opposite rotating directions; the front blade group is fixedly sleeved on the blade inner shaft, and the rear blade group is fixedly sleeved on the blade outer shaft; the front blade group rotates to drive the inner blade shafts to rotate, and the rear blade group rotates to drive the outer blade shafts to rotate;

the magnetic coupling device comprises an axial transmission mechanism and a radial transmission mechanism;

the axial transmission mechanism comprises an axial coupler input shaft, an axial coupler input rotor, an axial coupler output rotor and an axial coupler output shaft; the radial transmission mechanism comprises a radial coupling input shaft, a radial coupling inner rotor, a radial coupling outer rotor and a radial coupling output shaft; one end of the axial coupling input shaft is connected with the inner blade shaft, the outer part of the axial coupling input shaft is sleeved by the radial coupling input shaft, and the radial coupling input shaft is fixedly connected with the outer blade shaft; the inner rotor of the radial coupling is fixedly sleeved on the periphery of the input shaft of the radial coupling, one end of the outer rotor of the radial coupling is sleeved on the periphery of the inner rotor of the radial coupling, the outer rotor of the radial coupling is of a sleeve type structure, and two ends of the outer rotor of the radial coupling are supported in the middle shell through bearings; mounting grooves are formed in the positions, corresponding to the inner periphery of the outer rotor of the radial coupler, of the outer periphery of the inner rotor of the radial coupler, and permanent magnets which are symmetrically distributed, fan-shaped and different in polar direction are embedded in the mounting grooves; a radial coupling output shaft is fixedly sleeved inside the other end of the outer rotor of the radial coupling; a through hole is formed in the output shaft of the radial coupler; the other end of the input shaft of the axial coupler is fixedly sleeved with an input rotor of the axial coupler; the axial coupling output shaft and the axial coupling input shaft are arranged oppositely and are coaxial along the radial direction of the whole power generation device; the output rotor of the axial coupler and the input rotor of the axial coupler are oppositely arranged, the opposite surfaces of the output rotor and the input rotor of the axial coupler are provided with grooves, and permanent magnets which are symmetrically distributed, have fan-shaped shapes and have different polar directions are arranged in the grooves; the axial coupling output shaft is sleeved in the through hole of the radial coupling output shaft;

the outer rotor of the blade drives the input shaft of the radial coupling and the inner rotor of the radial coupling to rotate, and then drives the outer rotor of the radial coupling and the output shaft of the radial coupling to rotate through magnetic coupling; the inner shaft of the blade drives the input shaft of the axial coupler and the input rotor of the axial coupler to rotate, and then drives the output rotor of the axial coupler and the output shaft of the axial coupler to rotate through magnetic coupling;

the mechanical speed change device comprises a torque coupling device consisting of a first bevel gear, a second bevel gear, a third bevel gear, a central shaft and a bearing seat, and a speed increasing device consisting of a first gear, a second gear, a third gear, a fourth gear, a speed increasing shaft, a first bearing seat and a second bearing seat; the central shaft is coaxially and fixedly connected with the output shaft of the axial coupler, the first bevel gear is fixedly sleeved between the output shaft of the axial coupler and the output shaft of the radial coupler, and the second bevel gear is fixedly sleeved at the end part of the central shaft; the second bevel gear is meshed with the first bevel gear and the third bevel gear respectively, the central axis of the second bevel gear is perpendicular to the central axis, and the second bevel gear is connected with a bearing seat through a bearing and supported on the inner wall of the middle shell through the bearing seat; the torque of the output shaft of the axial coupler directly acts on the central shaft, and the torque of the output shaft of the radial coupler acts on the central shaft through the bevel gear to realize torque coupling;

the first gear is fixedly sleeved on a central shaft of the torque coupling device, the second gear and the third gear are fixedly sleeved on the speed increasing shaft, two ends of the speed increasing shaft are supported on the first bearing seat and the second bearing seat, the first bearing seat and the second bearing seat are distributed on one side of the central shaft in parallel, and the fourth gear is fixedly connected with a motor shaft. The first gear is meshed with the second gear, and the third gear is meshed with the fourth gear;

the generator device is positioned in the rear shell, the mechanical speed changing device drives the generator rotor to rotate, and induced electromotive potential energy is generated by cutting the magnetic induction lines, so that mechanical energy is converted into electric energy.

Furthermore, the steering and yawing device comprises a convection tail rudder and a steering device consisting of a strut, a platform bearing seat and a device platform; the convection tail vane is fixedly connected to the tail of the rear shell, and the adjusting device passively drifts to realize the incident flow and generate electricity; the device platform is fixed below the shell, the platform bearing seat is fixed on the support column, and the device platform is rotatably supported on the support column through a bearing.

Furthermore, the front blade group is of a three-blade structure, the rear blade group is of a four-blade structure, and the rotation directions of the front blade group and the rear blade group are opposite during working.

Further, the device also comprises a flow guide cover, wherein the flow guide cover is arc-shaped and is fixed in front of the front blade group.

Further, the middle shell comprises an outer shell and an inner shell which is nested inside the outer shell, the ends of the outer shell and the inner shell are connected, and the ends of the inner shell are sealed, so that after the middle shell and the rear shell are connected, a sealed cavity is formed inside the middle shell and the rear shell; the radial coupling outer rotor, the radial coupling output shaft, the axial coupling output rotor, the axial coupling output shaft, the mechanical speed changing device and the generator device are all located in the sealed cavity.

The invention has the following beneficial effects:

(1) according to the contra-rotating propeller ocean current energy power generation device applying the magnetic coupling, the yaw device is adopted to enable the generator to rotate freely within 360 degrees in the horizontal plane, so that passive yaw can be carried out along with the change of the ocean current direction to realize an incident flow function;

(2) the invention adopts the counter-rotating propellers to enhance the output torque of the impeller, thereby improving the output torque of the single impeller at low flow rate, leading the single impeller to have good starting performance under the working condition of low flow rate, and leading the submarine observation network to realize self-sufficiency of electric energy under the power consumption requirement of high-efficiency kinetic energy conversion rate.

(3) The invention relates to a magnetic coupling for transmitting torque, belongs to non-contact torque transmission, and has the characteristics of vibration isolation, noise isolation, strong capability of compensating the deviation of the coupling and no maintenance. And because direct contact is not needed when torque is transmitted, the moment loss caused by sealing isolation is small.

(4) The invention adopts a structure of combining an axial transmission mechanism and a radial transmission mechanism, and has compact structure and low space requirement under the condition of meeting the contra-rotating transmission.

Drawings

Fig. 1 is a schematic external structural view of a counter-rotating propeller ocean current energy power generation device applying a magnetic coupling according to an embodiment of the present invention;

FIG. 2 is a side view of a counter-rotating propeller ocean current energy power plant employing a magnetic coupling according to an embodiment of the present invention;

FIG. 3 is a cross-sectional view of a contra-rotating propeller ocean current energy power generation device employing a magnetic coupling;

FIG. 4 is a cross-sectional view of the magnetic coupling device;

FIG. 5 is a cross-sectional view taken along line A-A of FIG. 3;

FIG. 6 is a cross-sectional view taken along line B-B of FIG. 3;

wherein, 1 is a guide cover, 2 is a front blade group, 3 is a rear blade group, 4 is a guide shell, 5 is a connecting shell, 6 is a middle shell, 7 is a rear shell, 8 is a convection tail rudder, 9 is a device platform, 10 is a platform bearing seat, 11 is a support, 12 is a blade outer shaft, 13 is a blade inner shaft, 14 is a radial coupling input shaft, 15 is an axial coupling input shaft, 16 is a radial coupling inner rotor, 17 is an axial coupling input rotor, 18 is a radial coupling outer rotor, 19 is an axial coupling output rotor, 20 is a radial coupling output shaft, 21 is an axial coupling output shaft, 22 is a first gear, 23 is a fourth gear, 24 is a motor shaft, 25 is a generator, 26 is a generator housing, 27 is a second bearing seat, 28 is a speed increasing shaft, 29 is a fourth gear, 30 is a second gear, 31 is a first bearing seat, 32 is a third bevel gear, 33 is a central shaft, 34 is a bearing seat, 35 is a second bevel gear, 36 is a first bevel gear, and 37 is a permanent magnet.

Detailed Description

The present invention will be described in detail below with reference to the accompanying drawings and preferred embodiments, and the objects and effects of the present invention will become more apparent, it being understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the present invention. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.

As shown in fig. 1 to 3, the contra-rotating propeller ocean current energy power generation device applying the magnetic coupling according to the embodiment of the present invention includes a housing, contra-rotating impellers located outside the housing, a steering and yawing device, and a magnetic coupling device, a mechanical speed changing device and a generator device located inside the housing.

The shell comprises a flow guide shell 4, a connecting shell 5, a middle shell 6 and a rear shell 7 which are sequentially connected from front to back.

The contra-rotating impeller comprises a sleeved blade outer shaft 12 and a sleeved blade inner shaft 13, and a front blade group 2 and a rear blade group 3 which are coaxially arranged and opposite in rotation direction; the front blade group 2 is fixedly sleeved on the blade inner shaft 13, and the rear blade group 3 is fixedly sleeved on the blade outer shaft 12; the front blade group 2 rotates to drive the inner blade shaft 13 to rotate, and the rear blade group 3 rotates to drive the outer blade shaft 12 to rotate. The front blade group 2 and the rear blade group 3 rotate in opposite directions during work.

The magnetic coupling device comprises an axial transmission mechanism and a radial transmission mechanism, a relative movement gap is reserved between the axial transmission mechanism and the radial transmission mechanism, the two parts do not influence each other in the working process, and the transmission is relatively independent.

As shown in fig. 3 and 4, the axial transmission mechanism includes an axial coupling input shaft 15, an axial coupling input rotor 17, an axial coupling output rotor 19, and an axial coupling output shaft 21. Wherein the axial coupling input rotor 17 is similar to the axial coupling output rotor 19 in structure, and is a disc shape with a central shaft mounting hole, and permanent magnet mounting grooves uniformly distributed along the central shaft, and the two rotors are coaxially sleeved. Wherein, the permanent magnets 37 which are symmetrically distributed and in fan shape are embedded in the permanent magnet mounting grooves of the axial coupling input rotor 17 and the axial coupling input rotor 19. Wherein, the axial coupling input shaft 15 and the axial coupling output shaft 21 are arranged in the central shaft mounting holes of the axial coupling input rotor 17 and the axial coupling output rotor 19 and are fixedly connected.

The radial transmission mechanism comprises a radial coupling input shaft 14, a radial coupling inner rotor 16, a radial coupling outer rotor 18 and a radial coupling output shaft 20. The radial coupling input shaft 14 and the radial coupling output shaft 20 are both tubular and are respectively sleeved on the axial coupling input shaft 15 and the axial coupling output shaft 21. And the inner hole of the input and output shaft of the radial coupling is matched with the inner hole of the input and output shaft of the axial coupling in a clearance fit manner so as to move relatively. The radial coupling inner rotor 16 is sleeved on one side of a radial coupling input shaft 14, the radial coupling inner rotor 16 is in a ring shape, permanent magnet strip mounting grooves are uniformly distributed on the outer side of the radial coupling inner rotor 16, an inner hole is fixedly connected with the radial coupling input shaft 14, the radial coupling outer rotor 18 is sleeved on one side of a radial coupling output shaft 20, the radial coupling outer rotor 18 is in a cover shape with a hole in the middle, the mounting grooves of the axial coupling rotor and the permanent magnet mounting grooves which are uniformly distributed are reserved on the inner side of a cover edge, the radial coupling outer rotor 18 and the axial coupling input and output rotors 17 and 19 can move relatively in a clearance mode, the inner hole of the radial coupling outer rotor 18 is fixedly connected with the radial coupling output shaft 20, and the permanent magnet strip mounting grooves are uniformly arranged on the inner side of the cover edge of the radial coupling outer rotor 18. Wherein, the permanent magnets 37 which are symmetrically distributed are embedded in the mounting grooves at the outer side of the inner rotor 16 of the radial coupling and the inner side of the outer rotor 18 of the axial coupling.

As shown in fig. 5 and 6, the magnetic field transmission mode is coupled transmission in a permanent magnet heteropolar arrangement push-pull mode, and the magnetic poles of two adjacent permanent magnets on the same rotor are opposite in direction. When in transmission, the permanent magnet has the attraction effect between the two permanent magnets which are coupled with each other and also has the repulsion effect of the permanent magnet and the two adjacent permanent magnets of the coupled permanent magnet.

The mechanical speed change device comprises a torque coupling device and a speed increasing device, the torque coupling device achieves the functions of torque coupling and single-shaft output, and the speed increasing device achieves the function of matching of the power generation rotating speed and the torque.

Wherein the moment coupling device comprises a first bevel gear 36, a second bevel gear 35, a third bevel gear 32, a central shaft 33 and a bearing seat 34. Wherein, the center of the first bevel gear 36 is provided with a through hole, the first bevel gear 36 is fixedly connected with the radial coupling output shaft 20, and the axial coupling output shaft 21 passes through the center hole of the first bevel gear 36 and is fixedly connected with the central shaft 33. Wherein the third bevel gear 32 is sleeved on the central shaft and fixedly connected. Wherein the second bevel gear 35 is respectively meshed with the first bevel gear 36 and the third bevel gear 32, the central axis of the second bevel gear 35 is vertical to the central shaft 33, and the second bevel gear 35 is connected with the bearing seat 34 through a bearing. Wherein the central shaft 33 receives torque from the axial coupling output shaft 21 and the first bevel gear 36 receives torque from the radial coupling output shaft 20 and acts on the central shaft 33 with the second bevel gear 35 and the third bevel gear 32.

The speed increasing device comprises a first gear 22, a second gear 30, a third gear 29, a fourth gear 23, a speed increasing shaft 28, a first bearing seat 31 and a second bearing seat 27. Wherein the first gear 22 is sleeved on the central shaft 33 and fixedly connected. Wherein the first gear 22 is in mesh with the second gear 30. The second gear 30 and the third gear 29 are sleeved on the speed-increasing shaft 28 and fixedly connected, and two ends of the speed-increasing shaft 28 are fixed in the first bearing seat 31 and the second bearing seat 27 through bearings and are placed on one side of the central shaft 33 in parallel. Wherein the third gear 29 meshes with the fourth gear 23. Wherein the fourth gear 23 is sleeved on the motor shaft 24 and fixedly connected. Wherein the speed increasing device changes the rotating speed and the torque of the central shaft 33 through the meshing of the two groups of gears and transmits the rotating speed and the torque to the motor shaft 24.

The generator device comprises a motor shaft 24, a generator 25 and a generator shell 26. Wherein the generator 25 is fixed in the generator casing 26 and the generator casing 26 is mounted in the mounting slot of the rear housing 7. Wherein the rotor of the generator 25 is fixedly connected with the motor shaft 24. The motor shaft 24 drives the generator rotor to rotate by receiving the torque transmitted from the fourth gear 23, and the rotor cuts the magnetic induction lines to generate induced electromotive potential energy, so that mechanical energy is converted into electric energy.

The middle shell 6 comprises an outer shell and an inner shell nested inside the outer shell, the end parts of the outer shell and the inner shell are connected, the end parts of the inner shell are sealed, and therefore after the middle shell 6 and the rear shell 7 are connected, a sealed cavity is formed inside the middle shell. The radial coupling outer rotor 18, the radial coupling output shaft 20, the axial coupling output rotor 19, the axial coupling output shaft 21, the mechanical speed changing device and the generator device are all located in the sealed cavity, so that the sealed isolation of the contra-rotating magnetic coupling output and the generator output is realized. And the radial coupling input shaft 14 and the axial coupling input shaft 15 are positioned outside the sealed cavity and are immersed in water.

The steering and yawing device comprises a convection tail rudder and a steering device consisting of a strut 11, a platform bearing seat 10 and a device platform 9; the convection tail vane 8 is fixedly connected to the tail part of the rear shell 7, and the adjusting device passively drifts to realize the incident flow and generate electricity; the device platform 9 is fixed below the shell, the platform bearing seat 10 is fixed on the support column 11, and the device platform 9 is rotatably supported on the support column 11 through a bearing.

The efficiency and comprehensive factors simulating various aspects are considered, and in order to reduce the influence of wake flow among blade pieces and improve the capture efficiency of the front blade group on the ocean current energy, the front blade group 2 is of a three-blade structure. In order to improve the capture efficiency of the rear blade group on the ocean current energy and reduce the equipment cost, the rear blade group 3 is of a four-blade structure. In order to balance the moment of the equipment and reduce the influence of the wake flow of the front blade group on the rear blade group, the rotation directions of the front blade group 2 and the rear blade group 3 are different.

In specific application, the input and output rotors 17 and 19 of the axial coupling and the inner and outer rotors 16 and 18 of the radial coupling are made of non-magnetic materials, and the magnetic field of the permanent magnet cannot be influenced.

In order to fully utilize the space and improve the maximum transmission torque of the magnetic coupling, the permanent magnet 37 has a fan-shaped structure or a rectangular structure.

A gap is reserved between the axial transmission mechanism and the radial transmission mechanism, and the axial transmission and the radial transmission are mutually independent in the working process.

In order to make the flow field uniform and improve the efficiency of the blade group, the device also comprises a flow guide cover 1, wherein the flow guide cover 1 is arc-shaped and is fixed in front of the front blade group 2.

When the power generation device works, the steering mechanism passively drifts through the convection tail vane 8, convection is realized by passive incident flow, and the power generation device is enabled to be incident flow and enters a working state. The front blade group 2 and the rear blade group 3 are acted by ocean current moment, and the front and the rear blades are different in mounting direction in the incident flow direction, so that the front and the rear blades are different in rotating direction. The front blade group 2 drives the axial coupling input shaft 15 to rotate through the blade inner shaft 13, and the torque is input into the axial coupling; the rear blade group 3 drives the radial coupling input shaft 14 to rotate through the outer blade shaft 12, and the torque is input by the radial coupling. The axial coupling input shaft 15 rotates to drive the axial coupling input rotor 17 to rotate, the axial coupling input rotor 17 drives the axial coupling output rotor 19 to rotate through the magnetic coupling effect and outputs torque through the axial coupling output shaft 21, namely when the axial coupling input shaft 15 rotates, the axial coupling output shaft 21 synchronously rotates. The radial coupling input shaft 14 rotates to drive the radial coupling inner rotor 16 to rotate, and the radial coupling inner rotor 16 drives the radial coupling outer rotor 18 to rotate through the magnetic coupling effect and outputs torque through the radial coupling output shaft 20, namely, the radial coupling output shaft 20 synchronously rotates when the radial coupling input shaft 14 rotates. The central shaft 33 is fixedly connected with the axial coupling output shaft 21 and receives torque; the first bevel gear 36 is fixedly connected with the radial coupling output shaft 20 and meshed with the second bevel gear 35, and the first bevel gear 36 receives the torque of the radial coupling output shaft 20 and transmits the torque to the second bevel gear 35. The third bevel gear 32 is sleeved on the central shaft 33 and fixedly connected with the central shaft and meshed with the second bevel gear 35, and the third bevel gear 32 transmits the torque on the second bevel gear 35 to the central shaft 33, namely, the contra-rotating torque is synchronously input to the central shaft finally. One end of the central shaft 33 is sleeved with the first gear 22, the first gear 22 is meshed with the second gear 30, and the first gear 22 rotates along with the central shaft 33 and drives the second gear 30 to rotate. The second gear 30 and the third gear 29 are fixedly sleeved on the speed increasing shaft 28, and the second gear 30 drives the third gear 29 to rotate through the speed increasing shaft 28. The fourth gear 23 is fixedly sleeved on the motor shaft 24 and meshed with the third gear 28, and the third gear 28 transmits torque to the fourth gear 23 and drives the motor shaft 24 to rotate. The motor shaft 24 rotates to drive the generator rotor to rotate, and the rotor cuts the magnetic induction lines to generate induced electromotive potential energy, so that the kinetic energy of the ocean current is converted into mechanical energy, and the mechanical energy is converted into electric energy for equipment to use.

It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and although the invention has been described in detail with reference to the foregoing examples, it will be apparent to those skilled in the art that various changes in the form and details of the embodiments may be made and equivalents may be substituted for elements thereof. All modifications, equivalents and the like which come within the spirit and principle of the invention are intended to be included within the scope of the invention.