A coaxial differential rotating cam orthogonal gear type variable pitch propeller and control method

Abstract

The present invention relates to a coaxial differential rotating cam orthogonal gear variable pitch propeller and a control method. The present invention comprises a blade support outer shaft, a plurality of blades, a cam inner shaft and a transmission mechanism, wherein the blade support outer shaft is connected to the output end of a first speed change device; a plurality of blades are distributed at equal intervals in the circumferential direction of the blade support outer shaft, and the root of the blade is rotatably mounted on the blade support outer shaft through a mounting hole provided on the blade support outer shaft; one end of the cam inner shaft is connected to the second speed change device, and a cam is fixedly mounted on the other end, and the cam inner shaft and the cam are located on a straight line where the central axis of the blade support outer shaft is located; a track is provided on the outer wall of the cam; the number of the transmission mechanism is consistent with the number of the blades, one end of the transmission mechanism is slidably arranged on the track, and the other end of the transmission mechanism is rotatably connected to the root of the blade. The cam inner shaft and the blade support outer shaft of the present invention can be coaxially differentially rotated to achieve a change in pitch, so as to better adapt to the complex environment at sea.

Description

Technical Field

[0001] The invention relates to a propeller, and more particularly to a coaxial differential rotating cam orthogonal gear type variable pitch propeller and a control method thereof. Background Art

[0002] There are many kinds of propellers available now. A propeller is a device that converts the engine's rotational power into propulsion by rotating the blades in the air or water. The pitch refers to the pitch of the propeller surface: the propeller blade surface is the rotating surface. The intersection of any cylindrical surface coaxial with the propeller and the blade surface is a section of the helix. The section of the blade is obtained by intersecting the cylindrical surface and the blade, that is, the section of the blade is on the helix where the cylindrical surface and the blade surface intersect, and the axial distance between the two ends of the blade is equal to the pitch of the helix. It is customary to use the geometric moment at 70% of the diameter as the name value, also expressed as the blade angle.

[0003] When operating vessels travel through rivers, lakes, oceans, and ice oceans, the environment of the waters in which they are located changes significantly. The pitch of the propeller is designed according to a specific point of the working condition. When the ship is operating at a non-specific design point (such as changes in load, speed, and rotation speed), the pitch set by the fixed-pitch propeller cannot match the operating point, resulting in a decrease in the working efficiency of the propeller. In addition, when braking is required in an emergency, the fixed-pitch propeller can only stop first and then reverse, which is not as fast as the variable-pitch propeller that reverses the pitch to obtain reverse thrust.

[0004] Existing variable pitch propellers include hydraulic variable pitch propellers and elastic element adaptive variable pitch propellers. The hydraulic variable pitch propellers require a separate hydraulic system and push-pull rods, which are expensive. The elastic element adaptive variable pitch propellers are low-cost but cannot reverse the pitch to quickly provide reverse thrust in emergency avoidance. Summary of the invention

[0005] In view of the problems that the existing variable pitch propellers cannot reverse the pitch to quickly provide reverse thrust in emergency avoidance or are expensive, the present invention designs a coaxial differential rotating cam orthogonal gear variable pitch propeller and a control method. Without changing the direction of the propeller during normal operation, the inner shaft of the cylindrical cam and the outer shaft of the blade bracket can produce a differential through the gearbox, thereby changing the pitch, thereby effectively improving the propeller efficiency and achieving a rapid braking effect. It is not only low-cost, but also can quickly provide reverse thrust to shorten the necessary time for emergency avoidance.

[0006] In order to achieve the above object, the technical solution provided by the present invention is:

[0007] A coaxial differential rotating cam orthogonal gear variable pitch propeller and control method, comprising a blade holder outer shaft, a plurality of blades and a cam inner shaft, wherein the blade holder outer shaft is connected to the output end of a first speed change device; the plurality of blades are distributed at equal intervals in the circumferential direction of the blade holder outer shaft, and the roots of the blades are rotatably mounted on the blade holder outer shaft through mounting holes provided on the blade holder outer shaft; one end of the cam inner shaft is connected to the output end of a second speed change device, and a cam is fixedly mounted on the other end of the cam inner shaft, and the cam inner shaft and the cam are located on a straight line where the central axis of the blade holder outer shaft is located; a track is provided on the outer wall of the cam; and a transmission mechanism is also included, the number of the transmission mechanisms is consistent with the number of blades, one end of the transmission mechanism is slidably arranged on the track, and the other end of the transmission mechanism is rotatably connected to the root of the blade.

[0008] A further technical solution is that the transmission mechanism includes a gear connecting rod, a slider, a driving bevel gear and a driven bevel gear, the slider is fixed at one end of the gear connecting rod, the driving bevel gear is fixed at the other end of the gear connecting rod, the other end of the gear connecting rod is rotatably mounted on the inner wall of the outer shaft of the blade bracket, and the slider is slidably arranged in the track; the driven bevel gear is fixedly mounted on the root of the blade located inside the outer shaft of the blade bracket, and the driving bevel gear and the driven bevel gear are meshed with each other.

[0009] According to a further technical solution, the track is in a spiral shape.

[0010] According to a further technical solution, the shape of the track is a sinusoidal waveform.

[0011] A further technical solution is that a mounting platform for mounting the gear connecting rod is provided on the inner wall of the outer shaft of the blade bracket, and the number of the mounting platforms is consistent with the number of the gear connecting rods; each mounting platform is provided with a fixing block, and a fixing column is provided at the center position of the fixing block; a through hole is opened at one end of the gear connecting rod rotatably mounted on the inner wall of the outer shaft of the blade bracket, and the inner diameter of the through hole is consistent with the outer diameter of the fixing column.

[0012] According to a further technical solution, three blades are provided and are evenly spaced along the circumference of the outer axis of the blade bracket.

[0013] According to a further technical solution, the input ends of the first speed change device and the second speed change device are both connected to the ship power system.

[0014] A control method for a coaxial differential rotating cam orthogonal gear type variable pitch propeller adopts the above coaxial differential rotating cam orthogonal gear type variable pitch propeller, including the following control method:

[0015] During normal driving: the ship power system drives the first transmission device and the second transmission device to output the same speed, the outer shaft of the blade bracket and the inner shaft of the cam rotate at the same speed, the two remain relatively still, the transmission mechanism does not move, and the propeller pitch is fixed;

[0016] When the propeller pitch needs to be changed: driven by the ship's power system, the first speed change device and the second speed change device output different speeds, the outer shaft of the blade bracket and the inner shaft of the cam rotate to produce a speed difference, the two move relative to each other, the gear connecting rod of the transmission mechanism swings up and down along the track on the cam, the active bevel gear on the gear connecting rod drives the driven bevel gear to rotate, and the propeller pitch changes.

[0017] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects:

[0018] (1) The present invention provides a coaxial differential rotating cam orthogonal gear variable pitch propeller and control method. When the ship needs to adjust the thrust, the cam inner shaft and the blade bracket outer shaft realize differential rotation, thereby changing the blade angle of attack, and the rotation angles of each blade are the same, thereby realizing the change of reverse thrust or thrust. Compared with the traditional fixed propeller, it saves the time of stopping and reversing, can achieve the braking effect more quickly, and can better adapt to the complex environment at sea.

[0019] (2) The invention provides a coaxial differential rotating cam orthogonal gear variable pitch propeller and control method. The variable blade angle also enables the propeller to adapt to different environments, thereby improving the efficiency of the propeller. Compared with ordinary variable pitch propellers, only one power source is needed, and the power source can be the existing power system on the ship. No additional hydraulic power system is required, thus saving energy.

[0020] (3) The coaxial differential rotating cam orthogonal gear variable pitch propeller and control method of the present invention use a gear meshing transmission mode to achieve more accurate and convenient control. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a front view of the present invention;

[0022] Figure 2 A top view of the present invention;

[0023] Figure 3 It is a structural breakdown diagram of the present invention;

[0024] Figure 4 It is a side view of the transmission mechanism of the present invention;

[0025] Figure 5 It is a front view of the gear connecting rod of the transmission mechanism of the present invention;

[0026] Figure 6 It is a structural schematic diagram of the first track on the inner shaft of the cam of the present invention;

[0027] Figure 7 It is a schematic structural diagram of the second track on the inner shaft of the cam of the present invention;

[0028] Figure 8 This is a schematic diagram of the structure of the outer shaft of the blade support of the present invention;

[0029] Fig. 9 It is a schematic diagram of the follow-up trajectory of the gear connecting rod roller end and the ideal linear motion target trajectory of the present invention;

[0030] Fig.10 It is the actual track diagram on the cam of the present invention.

[0031] The numbers in the figure represent:

[0032] 1. Blade bracket outer shaft; 11. Mounting platform; 12. Fixing block; 13. Fixing column;

[0033] 2. Paddle blade; 3. Cam inner shaft; 4. Cam;

[0034] 5. Transmission mechanism; 51. Gear connecting rod; 511. Through hole; 52. Slider; 53. Active bevel gear; 54. Driven bevel gear;

[0035] 6. Track. DETAILED DESCRIPTION

[0036] In order to further understand the content of the present invention, the present invention is described in detail in conjunction with the accompanying drawings.

[0037] Example 1

[0038] A coaxial differential rotating cam orthogonal gear type variable pitch propeller and control method of this embodiment, such as Figure 3 As shown, it includes a blade support outer shaft 1, a plurality of blades 2, a cam inner shaft 3, a cam 4, a transmission mechanism 5 and a track 6. The blade support outer shaft 1 is connected to the output end of the first speed change device.

[0039] like Figure 6 As shown, one end of the cam inner shaft 3 is connected to the output end of the second speed change device, and the input ends of the first speed change device and the second speed change device are connected to the east-west system on the ship, and the kinetic energy is provided by the ship power system, saving energy. The other end of the cam inner shaft 3 is fixedly mounted with a cam 4, as shown in FIG. Figure 1 and 2 As shown, the cam 4 and the cam inner shaft 3 are both cylindrical in shape, the diameter of the cam 4 is larger than the diameter of the cam inner shaft 3, the central axis of the cam inner shaft 3 and the central axis of the cam 4 are located in a straight line, and the central axes of the cam inner shaft 3 and the cam 4 are located in a straight line with the central axis of the blade bracket outer shaft 1. A track 6 is provided on the outer wall of the cam 4.

[0040] like Figures 1 to 3As shown, in this embodiment, three blades 2 are provided, and the three blades 2 are evenly spaced along the circumference of the blade holder outer shaft 1 , and the root of the blade 2 is rotatably mounted on the blade holder outer shaft 1 through a mounting hole opened on the blade holder outer shaft 1 .

[0041] like Figure 2 As shown, the number of transmission mechanisms 5 is consistent with the number of blades 2, so there are three transmission mechanisms 5. One end of the transmission mechanism 5 is slidably arranged on the track 6, and the other end of the transmission mechanism 5 is rotatably connected to the root of the blade 2. The transmission mechanism 5 moves along the track 6. The transmission mechanism 5 is used to control the rotation of the blade 2. The rotation angle of the blade 2 is related to the design shape of the track 6.

[0042] Example 2

[0043] The present embodiment is a coaxial differential rotating cam orthogonal gear type variable pitch propeller and control method, the basic mechanism is the same as that of embodiment 1, such as Figure 3 , Figure 4 and Figure 5 As shown, the transmission mechanism 5 includes a gear connecting rod 51, a slider 52, a driving bevel gear 53 and a driven bevel gear 54. The slider 52 is fixed to one end of the gear connecting rod 51, and the driving bevel gear 53 is fixed to the other end of the gear connecting rod 51. The other end of the gear connecting rod 51 is rotatably mounted on the inner wall of the blade bracket outer shaft 1. The slider 52 is slidably arranged in the track 6. When moving, the slider 52 is tangent to the track 6. The driven bevel gear 54 is fixedly mounted on the root of the blade 2 located inside the blade bracket outer shaft 1, and the driving bevel gear 53 and the driven bevel gear 54 are meshed with each other. By driving the driving bevel gear 53 located on the gear connecting rod 51 to move, the driven bevel gear 54 is driven to rotate, thereby realizing the rotation of the blade 2.

[0044] Example 3

[0045] The present embodiment is a coaxial differential rotating cam orthogonal gear type variable pitch propeller and control method, the basic mechanism is the same as that of embodiment 2, such as Figure 6 As shown, the track 6 is in the shape of a spiral.

[0046] In order to prevent the propeller from being damaged by impact force as much as possible during the pitch change process, the present invention fits the motion trajectory curve of the propeller so that the change in pitch size is linearly related to the change in the relative motion arc size between the cam inner shaft 3 and the blade bracket outer shaft 1.

[0047] During the operation of the propeller, the motion trajectory of the end of the gear connecting rod 51 is an arc with the center of the active bevel gear 53 as the center. To ensure that the pitch can reach the optimal working pitch at both the positive and negative ends, the pitch of the gear connecting rod 51 is zero when it is in the horizontal position, and its end is at the axial midpoint of the trajectory of the cam inner shaft 3 when the gear connecting rod 51 is in the horizontal position.

[0048] The change in the pitch size is essentially the axial movement of the end of the gear connecting rod 51 on the cam inner shaft 3. The relative movement between the end of the gear connecting rod 51 and the cam inner shaft 3 is regarded as the blade bracket outer shaft 1 being stationary, the cam inner shaft 3 rotating, and the gear connecting rod 51 moving on the track 6 of the cam inner shaft 3. Then the shape of the track 6 on the cam inner shaft 3 needs to satisfy: the rotation angle of the cam inner shaft 3 is linearly related to the axial movement of the end of the gear connecting rod 51 on the cam inner shaft 3, so it is necessary to compensate for the arc trajectory of the end of the gear connecting rod 51.

[0049] Take the end of the trajectory as the origin, assume that the linearity of the relative motion trajectory is k, and the pitch variation range is θ. The fitting process is as follows: Fig. 9 As shown, the horizontal axis represents the arc of relative motion of the inner and outer axes, and the vertical axis represents the motion distance of the end of the gear connecting rod parallel to the axial direction: The target trajectory of the ideal linear motion is Fig. 9 The linear trajectory in y=kx, x∈(0,2π); the arc trajectory of the end of the gear connecting rod 51 is Fig. 9 The arc track in: When not synthesized, the roller follower track of the end of the gear connecting rod 51 is Fig. 9 The arc track in the figure: Since the motion track of the gear connecting rod 51 is arranged symmetrically in the axial direction, the coordinates of the center of the moving track of the roller end of the gear connecting rod 51 when not synthesized are The radius is Therefore, the arc trajectory equation is y∈(0, 2kπ). x represents the relative motion arc of the inner and outer shafts, and y represents the motion distance of the end of the gear connecting rod parallel to the axial direction.

[0050] like Fig.10 As shown, the horizontal axis represents the arc of relative motion of the inner and outer axes, and the vertical axis represents the motion distance of the end of the gear connecting rod parallel to the axial direction. The linear trajectory y=kx and the trajectory equation are Adding together, the equation of the trajectory curve of the track 6 on the cam 4 is expressed as: x∈(0,2π).

[0051] Example 4

[0052] The present embodiment is a coaxial differential rotating cam orthogonal gear type variable pitch propeller, the basic mechanism is the same as that of the embodiment 2, such as Figure 7 As shown, the shape of the track 6 is a sine wave. To match the sine wave shape of the track 6, the meshing mode of the driving bevel gear 53 and the driven bevel gear 54 is orthogonal. The track of the sine wave is continuous, and only one transmission is needed for control, which saves costs.

[0053] Example 5

[0054] The present embodiment is a coaxial differential rotating cam orthogonal gear type variable pitch propeller and control method, the basic mechanism is the same as that of embodiment 3, such as Figure 8 As shown, a mounting platform 11 for mounting the gear connecting rod 51 is provided on the inner wall of the blade bracket outer shaft 1, and the number of the mounting platforms 11 is consistent with the number of the gear connecting rods 51. Therefore, in this embodiment, three mounting platforms 11 are provided, each mounting platform 11 is provided with a fixing block 12, and a fixing column 13 is vertically provided at the center position of each fixing block 12. A through hole 511 is provided at one end of the gear connecting rod 51 rotatably mounted on the inner wall of the blade bracket outer shaft 1, and the inner diameter of the through hole 511 is consistent with the outer diameter of the fixing column 13. The fixing column 13 passes through the through hole 511 on the gear connecting rod 51, so that the gear connecting rod 51 rotates around the fixing column 13.

[0055] Example 6

[0056] This embodiment is a coaxial differential rotating cam orthogonal gear type variable pitch propeller and control method, the basic mechanism is the same as that of embodiment 5, and the method for changing the angle of attack of the blade 2 is as follows;

[0057] During normal driving: driven by the ship's power system, power is input to the first speed change device and the second speed change device, the first speed change device and the second speed change device output the same rotational speed, the blade bracket outer shaft 1 and the cam inner shaft 3 rotate at the same speed; the cam inner shaft 3 and the blade bracket outer shaft 1 remain relatively stationary, the transmission mechanism 5 does not move, the propeller pitch is fixed, and the propeller works normally.

[0058] When the pitch needs to be changed: under the drive of the ship's power system, power is input into the first speed change device and the second speed change device. The first speed change device and the second speed change device have different output rotation speeds, which causes a speed difference between the cam inner shaft 3 and the blade bracket outer shaft 1. The cam inner shaft 3 and the blade bracket outer shaft 1 move relative to each other, and the track 6 on the cam 4 is used to make the gear connecting rod 51 swing up and down along the shape of the track 6, so that the active bevel gear 53 fixed on the gear connecting rod 51 rotates, and the driven bevel gear 54 is driven to rotate through the active bevel gear 53, so that the pitch changes, and the rotation angles of each blade 2 are the same, thereby realizing a change in reverse thrust or thrust, and allowing the propeller to reach the optimal blade angle in different water environments, thereby improving the efficiency of the propeller.

[0059] The above working processes are converted to each other by adjusting the rotation speed output by the first speed changing device and the second speed changing device to realize the change of reverse thrust or thrust, so as to change the driving direction of the ship. Moreover, the ship can realize speed regulation, hovering, etc. by adjusting the angle of attack of the blade 2 during operation, thereby improving the efficiency of the propeller in different environments, achieving the braking effect more quickly, having a simple structure, strong practicality, and being more adaptable to the complex environment at sea.

[0060] The present invention and its embodiments are described schematically above, and the description is not restrictive. The drawings show only one embodiment of the present invention, and the actual structure is not limited thereto. Therefore, if a person skilled in the art is inspired by it and designs a structural method and an embodiment similar to the technical solution without creativity without departing from the purpose of the invention, they shall all fall within the protection scope of the present invention.

Claims

1. A coaxial differentially rotating cam orthogonal gear type variable pitch propeller, comprising a blade support outer shaft (1), a plurality of blades (2) and a cam inner shaft (3), wherein the blade support outer shaft (1) is connected to the output end of a first speed change device; the plurality of blades (2) are distributed at equal intervals in the circumferential direction of the blade support outer shaft (1), and the roots of the blades (2) are rotatably mounted on the blade support outer shaft (1) through mounting holes provided in the blade support outer shaft (1); one end of the cam inner shaft (3) is connected to the output end of a second speed change device, and a cam (4) is fixedly mounted on the other end; the characteristics are as follows: The central axes of the cam inner shaft (3) and the cam (4) are located on a straight line with the central axis of the blade bracket outer shaft (1); a track (6) is provided on the outer wall of the cam (4); and a transmission mechanism (5) is also included, the number of the transmission mechanisms (5) being the same as the number of the blades (2); one end of the transmission mechanism (5) is slidably arranged on the track (6), and the other end of the transmission mechanism (5) is rotatably connected to the root of the blade (2); the track (6) is in a spiral shape, and the cam (4) and the cam inner shaft (3) are both in a cylindrical shape.

2. The coaxial differential rotating cam orthogonal gear variable pitch propeller according to claim 1, characterized in that: The transmission mechanism (5) comprises a gear connecting rod (51), a slider (52), a driving bevel gear (53) and a driven bevel gear (54); the slider (52) is fixed to one end of the gear connecting rod (51); the driving bevel gear (53) is fixed to the other end of the gear connecting rod (51); the other end of the gear connecting rod (51) is rotatably mounted on the inner wall of the blade bracket outer shaft (1); the slider (52) is slidably arranged in the track (6); the driven bevel gear (54) is fixedly mounted on the root of the blade (2) located inside the blade bracket outer shaft (1); the driving bevel gear (53) and the driven bevel gear (54) are meshed with each other.

3. The coaxial differential rotating cam orthogonal gear variable pitch propeller according to claim 2, characterized in that: The shape of the track (6) is replaced by a sinusoidal waveform.

4. The coaxial differential rotating cam orthogonal gear variable pitch propeller according to claim 3, characterized in that: A mounting platform (11) for mounting the gear connecting rod (51) is provided on the inner wall of the blade support outer shaft (1), and the number of the mounting platforms (11) is the same as the number of the gear connecting rods (51); each mounting platform (11) is provided with a fixing block (12), and a fixing column (13) is provided at the center of the fixing block (12); a through hole (511) is provided at one end of the gear connecting rod (51) rotatably mounted on the inner wall of the blade support outer shaft (1), and the inner diameter of the through hole (511) is the same as the outer diameter of the fixing column (13).

5. The coaxial differential rotating cam orthogonal gear type variable pitch propeller according to claim 4, characterized in that: The blades (2) are provided with three blades (2) which are distributed at equal intervals along the circumference of the blade support outer shaft (1).

6. The coaxial differential rotating cam orthogonal gear variable pitch propeller according to claim 5, characterized in that: The input ends of the first speed change device and the second speed change device are both connected to the ship power system.

7. A control method for a coaxial differential rotating cam orthogonal gear variable pitch propeller, using the coaxial differential rotating cam orthogonal gear variable pitch propeller according to any one of claims 1 to 6, characterized in that: The control methods include: During normal travel: the ship power system drives the first speed change device and the second speed change device to output the same rotation speed, the propeller blade bracket outer shaft (1) and the cam inner shaft (3) rotate at the same speed, the two remain relatively stationary, the transmission mechanism (5) does not move, and the propeller pitch is fixed; When the propeller pitch needs to be changed: under the drive of the ship power system, the first speed change device and the second speed change device output different rotation speeds, the propeller blade bracket outer shaft (1) and the cam inner shaft (3) rotate to generate a speed difference, the two perform relative motion, the gear connecting rod (51) of the transmission mechanism (5) swings up and down along the track (6) on the cam (4), the active bevel gear (53) on the gear connecting rod (51) drives the driven bevel gear (54) to rotate, and the propeller pitch changes.

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