Electromechanical servo variable pitch mechanism for small and medium-sized underwater vehicle

Abstract

The invention relates to an electromechanical servo variable-pitch mechanism for small and medium-sized underwater vehicles, which recombines the functions of a ball nut sleeve, a ball nut sleeve bracket, a guide strip and a decoupling bearing, and achieves the purposes that a variable-pitch motor is fixed, and a lead screw transmission assembly only transmits variable-pitch thrust and does not rotate along with a hub. The variable pitch motor and the aircraft are fixed together through the fixed supporting frame, electric power and communication signals of the variable pitch motor can be conveniently transmitted, and the problem caused by using a sliding ring is avoided. According to the invention, electromechanical servo is adopted to realize pitch change, the problem of pitch change of small and medium-sized underwater vehicles is solved, and the development requirement of full electrification is met at the same time.

Description

Technical Field

[0001] The invention discloses a propulsion system for small and medium-sized submersibles, and relates to a propeller electromechanical servo pitch-changing mechanism for small and medium-sized submersibles. Background Art

[0002] The blade edge of the propeller corresponds to a spiral line, and the "pitch" of the pitch mechanism refers to the pitch of this spiral line. The use of a propulsion device with a variable pitch function can improve propulsion efficiency and save energy in a wide speed range. At the same time, the variable pitch propeller reduces the cavitation at the edge of the blade and can also reduce the noise of the propeller. The underwater propulsion device using a fixed pitch propeller can no longer meet the development needs of high propulsion efficiency and low noise. The pitch can be changed by rotating the blade relative to the hub and changing the blade angle. At present, hydraulic variable pitch propeller technology has been widely used in large ships, such as cargo ships and passenger ships. Many small and medium-sized unmanned submersibles use batteries as primary energy sources. The total weight of the vehicle is not large, and it is not suitable to be equipped with a complex hydraulic system. Hydraulic variable pitch technology generally adopts a push-pull rod variable pitch solution, which needs to be equipped with corresponding pistons, cylinders, hydraulic pumps, hydraulic pipelines, etc., which will inevitably lead to complex system solutions and poor maintainability. In addition, submersibles that use batteries as primary energy sources have the trend of full electrification, so the electromechanical servo variable pitch mechanism has a good application prospect.

[0003] "Variable pitch mechanism of wind turbine (CN101397262A)" uses a crank-connecting rod mechanism to drive, and realizes synchronous change of blade angle of all blades through a fork frame. The variable pitch motor in this patent is fixed to the hub, and the variable pitch motor always rotates with the hub. The power and communication signals required by the rotating parts need to be transmitted using slip rings. However, slip rings are easy to wear and there is a risk of sparks. When used on underwater equipment, it will also increase the difficulty of sealing, which leads to poor maintainability and reliability.

[0004] "Push-pull rod type adjustable propeller (CN202046432U)", the push-pull rod is driven by a cylinder and needs to be equipped with a hydraulic system. Its solution cannot be directly used in an electromechanical servo pitch-changing mechanism. Summary of the invention

[0005] The technical problem solved by the present invention is: in view of the pitch change requirements and full electrification requirements of small and medium-sized unmanned submersibles using batteries as primary energy sources, the deficiencies of the prior art are overcome and an electromechanical servo pitch change mechanism for small and medium-sized submersibles is proposed.

[0006] The solution of the present invention is:

[0007] An electromechanical servo pitch-changing mechanism for small and medium-sized submersibles, comprising a wheel hub, a blade shaft, a slider, a decoupling bearing, a ball nut sleeve, a ball nut, a ball screw, a screw support bearing, a pitch-changing motor, a pitch-changing motor mounting flange, a ball nut sleeve bracket, a guide bar, a support frame, and a sliding shoe;

[0008] N blade shaft holes are evenly distributed around the wheel hub, and a blade shaft is installed in each blade shaft hole; a columnar pin is provided on the side of the blade shaft facing the inner side of the wheel hub, a sliding shoe is installed on the columnar pin, and a blade is installed on the outer side of the blade shaft; the slider is installed in the central opening of the wheel hub, and N L-shaped sliding grooves are provided on the slider. After installation, the sliding shoe corresponds to the L-shaped sliding groove one by one, that is, each sliding shoe is located in a corresponding L-shaped sliding groove; a sleeve sliding groove is provided on the ball nut sleeve, and a guide strip is fixed on the ball nut sleeve bracket, and the guide strip is located In the sleeve groove, the two form a sliding friction pair; the front end of the ball nut sleeve bracket is fixedly connected to the support frame through a flange, and the support frame is fixedly connected to the aircraft shell; the rear end of the ball nut sleeve bracket is fixedly connected to the pitch motor through the motor mounting flange, and the output shaft of the pitch motor is connected to the ball screw through a coupling, the ball nut is threaded on the ball screw, and the ball nut and the ball nut sleeve are fixedly connected with screws, and the rear end cover of the wheel hub is connected to the support frame through the end cover bearing; the decoupling bearing is fixed to the front end of the ball nut sleeve and is fixedly connected to the slider.

[0009] Preferably, the inner ring of the decoupling bearing is fixedly connected to the ball nut sleeve by a locking nut, the decoupling bearing cover is pressed on the outer ring of the decoupling bearing, and the decoupling bearing cover, the outer ring of the decoupling bearing and the slider are fixedly connected by screws.

[0010] Preferably, a sealing ring is provided between the rear end cover of the wheel hub and the support frame.

[0011] Preferably, the blade shaft is an integrated structure with a disc-shaped structure in the middle, one side of the disc-shaped structure is a columnar protrusion, and the other side is provided with a columnar pin, and the diameter of the columnar protrusion is much larger than the diameter of the columnar pin.

[0012] Preferably, the columnar pin is away from the center of the disc-shaped structure.

[0013] Preferably, during installation, one side of the columnar pin faces the inner side of the hub, and one side of the columnar protrusion is used for installing the blade.

[0014] Preferably, the sliding shoe is clearance-fitted with the columnar pin.

[0015] Preferably, the slider is square, a corresponding square hole is opened in the center of the hub, and the slider is installed in the square hole in a clearance fit manner.

[0016] Preferably, the slider rotates synchronously with the wheel hub.

[0017] Preferably, when pitch change is not required, the ball screw, ball nut and inner ring of the decoupling bearing are stationary relative to the aircraft hull.

[0018] The beneficial effects of the present invention compared with the prior art are:

[0019] (1) Many small and medium-sized underwater vehicles powered by batteries are not conveniently equipped with complex hydraulic systems. The present invention uses electromechanical servo to achieve pitch change, which solves the pitch change problem of small and medium-sized underwater vehicles and meets the development requirements of full electrification.

[0020] (2) The variable pitch motor of the present invention does not rotate together with the wheel hub. The variable pitch motor is fixed to the aircraft through a fixed support frame. The power and communication signals of the variable pitch motor can be easily transmitted, thus avoiding the problems caused by the use of slip rings.

[0021] (3) The present invention recombines the functions of the ball nut sleeve, the ball nut sleeve bracket, the guide bar and the decoupling bearing, thereby achieving the purpose of fixing the variable pitch motor and allowing the screw transmission assembly to only transmit the variable pitch thrust and not rotate with the wheel hub.

[0022] (4) Compared with the electromechanical servo pitch-changing technology of the fan, the connecting rod, crankshaft, fork arm and other parts are eliminated and replaced by a simple ball nut sleeve, which improves the bearing capacity of the pitch-changing mechanism. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the pitch changing mechanism when the blade angle is 0°;

[0024] Figure 2 It is a schematic diagram of the pitch-changing mechanism when the blade angle is 30°;

[0025] Figure 3 It is a schematic diagram of the blade shaft structure;

[0026] Figure 4 Schematic diagram of the positional relationship between the petiole and the sliding shoe, where (a) is the positional relationship when the blade angle is 0°, and (b) is the positional relationship when the blade angle is 30°;

[0027] Figure 5 It is a schematic diagram of the slider structure;

[0028] Figure 6 It is a schematic diagram of the ball nut sleeve structure. DETAILED DESCRIPTION

[0029] The present invention will be further described below in conjunction with the accompanying drawings.

[0030] The present invention is a pitch-changing mechanism for an underwater vehicle, comprising a wheel hub 1, a blade shaft 2, a slider 3, a decoupling bearing 4, a ball nut sleeve 5, a ball nut 6, a ball screw 7, a screw support bearing 8, a pitch-changing motor 9, a pitch-changing motor mounting flange 10, a ball nut sleeve bracket 11, a guide bar 12, a support frame 13, a sliding shoe 14, a decoupling bearing locking nut 15, and a decoupling bearing gland 16. Figure 1 and Figure 2 As shown. The hub 1 has N blade shaft holes evenly distributed around the circumference, and each blade shaft hole is equipped with a blade shaft 2. N is a positive integer. In a preferred embodiment, N=4. The structure of the blade shaft 2 is as shown Figure 3 As shown, the blade shaft 2 is an integrated structure, with a disc-shaped structure in the middle, a columnar protrusion on one side of the disc-shaped structure, and a columnar pin on the other side. The diameter of the columnar protrusion is much larger than the diameter of the columnar pin. The columnar pin is far away from the center of the disc-shaped structure. When installing, one side of the columnar pin faces the inner side of the hub, and one side of the columnar protrusion is used to install the blade.

[0031] The columnar pin is used to install the sliding shoe 14. After the blade shaft 2 is installed in the blade shaft hole of the hub 1, it can rotate; after the sliding shoe 14 is installed on the columnar pin of the blade shaft 2, it can also rotate. Figure 4 The positional relationship between the blade shaft 2 with the sliding shoe 14 installed and the hub 1 is shown when the blade angles are 0° and 30° respectively. Figure 5 As shown, the slider 3 is square and is installed in the central opening of the wheel hub 1. The slider 3 is provided with N L-shaped slots, and the N L-shaped slots correspond to the N sliding shoes. After assembly, the sliding shoes 14 can slide in the corresponding L-shaped slots and only move in the slots perpendicular to the axis of the wheel hub. The ball nut sleeve 5 is provided with slots, such as Figure 6 As shown. The guide bar 12 is fixed to the ball nut sleeve bracket 11 by screws. After assembly, the slide groove of the ball nut sleeve 5 and the guide bar 12 form a sliding friction pair, which means that the ball nut sleeve 5 can only move axially relative to the ball nut sleeve bracket 11, but cannot rotate. The front end of the ball nut sleeve bracket 11 is fixedly connected to the support frame 13 through a flange, and the support frame 13 is fixed to the aircraft shell. The rear end of the ball nut sleeve bracket 11 is fixedly connected to the variable pitch motor 9 through the motor mounting flange 10. The output shaft of the variable pitch motor 9 is connected to the ball screw 7 through a coupling, the ball nut 6 is installed on the ball screw 7, and the ball nut 6 is fixedly connected to the ball nut sleeve 5 by screws. The rear end cover of the hub 1 is connected to the support frame 13, and the connection is provided with an end cover bearing and a sealing ring. The inner ring of the decoupling bearing 4 is fixedly connected to the ball nut sleeve 5 by a locking nut 15, and the outer ring of the decoupling bearing 4 is fixed to the slider 3 by a decoupling bearing pressure cover 16.

[0032] The sliding shoe is clearance-fitted with the cylindrical pin. The slider is installed in the wheel hub opening in a clearance-fitted manner.

[0033] The pitch-changing working principle of the present invention is as follows: after receiving the command, the pitch-changing motor 9 drives the ball screw 7 to rotate the specified angle, so that the ball nut 6 moves the corresponding distance; according to the connection relationship described above, the ball nut sleeve 5, the decoupling bearing 4 and the slider 3 will move the same distance as the ball nut 6 along the axis of the wheel hub; the slide groove of the slider 3 pushes the sliding shoe 14 to move the same distance as the ball nut 6 along the axis of the wheel hub; at the same time, the sliding shoe 14 moves a certain distance in the slide groove of the slider 3 in the direction perpendicular to the axis of the wheel hub, so that the sliding shoe 14 drives the blade shaft 2 to rotate a certain angle. The blade is fixedly connected to the blade shaft 2, so that the propeller pitch can be changed. Figure 1 , Figure 2 They are schematic diagrams of the pitch-changing mechanism when the blade angles are 0° and 30° respectively. By comparison, it can be seen that compared with the case of 0°, the ball nut 6, the ball nut sleeve 5, the decoupling bearing 4, the sliding shoe 14 and the slider 3 have all moved a certain distance to the left at 30°.

[0034] During the pitch change process, the sliding shoe 14 moves along the axis of the hub relative to the wheel hub, and also slides in the slide groove of the slider 3 in a direction perpendicular to the axis of the hub. The resultant movement of the center of the sliding shoe 14 is a fixed-axis rotation around the axis of the blade shaft 2. The slider 3 can move along the axis of the hub and rotate relative to the ball nut sleeve 5. The slider 3 needs to have several slide grooves if there are several blades on the propeller. The function of the decoupling bearing 4 is to transmit the axial movement of the ball nut sleeve 5 to the slider 3 and prevent the ball nut sleeve 5 from rotating with the slider 3. The slider 3 always rotates synchronously with the wheel hub 1. When pitch change is not required, the ball screw 7, ball nut 6 and the inner ring of the decoupling bearing 4 are stationary relative to the aircraft shell.

[0035] The present invention uses electromechanical servo to achieve pitch change, which solves the pitch change problem of small and medium-sized underwater vehicles that use batteries as primary energy, and meets the development requirements of full electrification. The pitch-changing motor of the present invention is fixed to the vehicle through other parts, does not rotate with the wheel hub, and avoids the problems caused by the use of slip rings to transmit electricity. The electromechanical servo pitch change technical solution of the fan eliminates the connecting rod, crankshaft, fork arm and other parts, and replaces them with a simple ball nut sleeve, which improves the bearing capacity of the pitch change mechanism.

[0036] The undisclosed technologies in the present invention are common knowledge to those skilled in the art.

Claims

1. An electromechanical servo pitch-changing mechanism for small and medium-sized submersibles, characterized in that: It comprises a wheel hub (1), a blade shaft (2), a slider (3), a decoupling bearing (4), a ball nut sleeve (5), a ball nut (6), a ball screw (7), a screw support bearing (8), a pitch-changing motor (9), a pitch-changing motor mounting flange (10), a ball nut sleeve bracket (11), a guide strip (12), a support frame (13), and a sliding shoe (14); The wheel hub (1) is provided with N blade shaft holes evenly distributed in the circumferential direction, and each blade shaft hole is provided with a blade shaft (2); a columnar pin is provided on the side of the blade shaft (2) facing the inner side of the wheel hub (1), and a sliding shoe (14) is provided on the columnar pin, and a blade is provided on the outer side of the blade shaft (2); a slider is installed in the central opening of the wheel hub (1), and N L-shaped sliding grooves are provided on the slider (3); after being installed in place, the sliding shoe corresponds to the L-shaped sliding groove one by one, that is, each sliding shoe is located in a corresponding L-shaped sliding groove; a sleeve sliding groove is provided on the ball nut sleeve (5), a guide strip (12) is fixed on the ball nut sleeve bracket (11), and the guide strip (12) is located in the sleeve sliding groove, and the two are in the shape of The front end of the ball nut sleeve bracket (11) is fixedly connected to the support frame (13) through a flange, and the support frame (13) is fixedly connected to the aircraft shell; the rear end of the ball nut sleeve bracket (11) is fixedly connected to the variable pitch motor (9) through a motor mounting flange (10), the output shaft of the variable pitch motor (9) is connected to the ball screw (7) through a coupling, the ball nut (6) is screwed onto the ball screw (7), and the ball nut (6) and the ball nut sleeve (5) are fixedly connected with screws, and the rear end cover of the wheel hub (1) is connected to the support frame (13) through an end cover bearing; the decoupling bearing (4) is fixed to the front end of the ball nut sleeve (5) and is fixedly connected to the slider (3).

2. The electromechanical servo pitch-changing mechanism for small and medium-sized submersibles according to claim 1, characterized in that: The inner ring of the decoupling bearing (4) is fixedly connected to the ball nut sleeve (5) via a locking nut (15), the decoupling bearing pressure cover (16) is pressed on the outer ring of the decoupling bearing (4), and the decoupling bearing pressure cover (16), the outer ring of the decoupling bearing (4) and the slider (3) are fixedly connected via screws.

3. The electromechanical servo pitch-changing mechanism for small and medium-sized submersibles according to claim 1, characterized in that: A sealing ring is provided between the rear end cover of the wheel hub (1) and the support frame (13).

4. The electromechanical servo pitch-changing mechanism for small and medium-sized submersibles according to claim 1, characterized in that: The blade shaft (2) is an integrated structure with a disc-shaped structure in the middle. One side of the disc-shaped structure is a columnar protrusion, and the other side is provided with a columnar pin. The diameter of the columnar protrusion is much larger than the diameter of the columnar pin.

5. The electromechanical servo pitch-changing mechanism for small and medium-sized submersibles according to claim 4, characterized in that: The cylindrical pin is away from the center of the disc-shaped structure.

6. The electromechanical servo pitch-changing mechanism for small and medium-sized submersibles according to claim 5, characterized in that: During installation, one side of the columnar pin faces the inner side of the hub (1), and one side of the columnar protrusion is used for installing the blade.

7. The electromechanical servo pitch-changing mechanism for small and medium-sized submersibles according to claim 1, characterized in that: The sliding shoe (14) is clearance-matched with the columnar pin.

8. The electromechanical servo pitch-changing mechanism for small and medium-sized submersibles according to claim 1, characterized in that: The slider (3) is square, and a corresponding square hole is opened at the center of the wheel hub (1). The slider is installed in the square hole in a clearance fit manner.

9. The electromechanical servo pitch-changing mechanism for small and medium-sized submersibles according to claim 1, characterized in that: The slider (3) rotates synchronously with the wheel hub (1).

10. The electromechanical servo pitch-changing mechanism for small and medium-sized submersibles according to claim 1, characterized in that: When there is no need to change the pitch, the ball screw (7), the ball nut (6) and the inner ring of the decoupling bearing (4) are stationary relative to the aircraft shell.

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