Turbine energy-capture hydraulic variable-pitch mechanism

Abstract

The application discloses a turbine energy-capturing hydraulic variable-pitch mechanism, which comprises a transmission shaft, a radial support bearing I, a cylinder, a hollow rack piston rod, a radial support bearing II and turbine blades; the hollow rack piston rod is a hollow rod structure, is coaxially sleeved on the transmission shaft and is supported in the cylinder through the radial support bearing I and the radial support bearing II; a plurality of turbine blades are installed on the input end of the transmission shaft and are in gear pair transmission cooperation with U-shaped grooves arranged on the hollow rack piston rod corresponding to the input end of the transmission shaft; two oil cavities are formed between the hollow rack piston rod and the cylinder, the two oil cavities are connected with a hydraulic system, pressure oil is input into different oil cavities to drive the hollow rack piston rod to move linearly to the left or to the right, so as to drive the turbine blades to rotate forward or reversely; wherein the turbine blades rotate forward to increase the pitch angle, and reversely to reduce the pitch angle.

Description

Technical Field

[0001] This invention relates to the field of turbine energy capture or variable pitch propulsion technology, specifically to a turbine energy capture hydraulic variable pitch mechanism. Background Technology

[0002] Hydroelectric turbines are increasingly used in energy capture and power generation, such as ocean current energy generation and towed energy capture. However, the speed of ocean or river currents varies frequently. Even with towed energy capture, changes in ship speed alter the current velocity. Often, at lower current velocities, the turbine needs to increase its pitch angle to improve capture efficiency and increase energy input. Conversely, at higher current velocities, the turbine needs to decrease its pitch angle to reduce capture efficiency and energy input, ensuring equipment safety. Using variable-pitch turbines, which adjust the turbine pitch angle according to the current velocity, effectively solves these problems. Furthermore, many devices currently using underwater turbines for power generation convert the turbine's energy input into hydraulic energy, which is then directly output as hydraulic energy. In this way, hydraulic energy becomes an ideal driving power source for variable-pitch turbines.

[0003] Current turbine blade pitch angle adjustment generally uses a separate electric actuator (such as a motor) or hydraulic actuator (such as a hydraulic cylinder) to drive the pitch angle change. This method has the following problems:

[0004] 1. Hydrodynamic turbine blades generally use at least three blades. Since each blade is driven independently, there are often many variable pitch drive components. Even if a single drive input and multi-link mechanism multi-output drive method is used, it will still lead to structural complexity. In addition, more actuators and complex structures will lead to larger structural dimensions.

[0005] 2. The presence of numerous drive components complicates the synchronous control of blade pitch angle. To achieve consistent changes in blade pitch angle, more sensors are needed to detect parameters such as displacement and rotation angle, followed by synchronous control, which makes the system control more complex. Summary of the Invention

[0006] In view of this, the present invention provides a turbine energy capture hydraulic pitch variable mechanism for underwater turbine energy capture equipment. It uses a hydraulic system to control and drive the turbine blades to achieve pitch variable, which solves the problem of the complexity of the turbine blade pitch variable mechanism in current energy conversion equipment that uses turbine energy capture input and hydraulic energy storage output.

[0007] The technical solution of the present invention is: a turbine energy capture hydraulic pitch mechanism, comprising: a drive shaft, a radial support bearing I, a cylinder, a hollow rack piston rod, a radial support bearing II, and turbine blades;

[0008] The hollow rack piston rod is a hollow rod-shaped structure, which is coaxially mounted on the drive shaft and supported in the cylinder by radial support bearing I and radial support bearing II; multiple turbine blades are installed at the input end of the drive shaft and form a gear pair transmission with the U-shaped groove on the hollow rack piston rod corresponding to the input end of the drive shaft.

[0009] The hollow rack piston rod forms two oil chambers with the cylinder. Both oil chambers are connected to the hydraulic system. By inputting pressurized oil into different oil chambers, the hollow rack piston rod is driven to move linearly to the left or right, thereby driving the turbine blades to rotate in the forward or reverse direction. The forward rotation of the turbine blades increases the pitch angle, while the reverse rotation decreases the pitch angle.

[0010] Preferably, it further includes: piston end cap I and piston end cap II, wherein the hollow rack piston rod has a shoulder at the axial center, which divides the cavity between the hollow rack piston rod and the cylinder into two oil chambers; the inner wall surface of the cylinder and the shoulder of the hollow rack piston rod are sealed by a sealing ring; piston end cap I and piston end cap II are coaxially fitted on both ends of the hollow rack piston rod and abut against both ends of the cylinder, and piston end cap I and piston end cap II are sealed with the hollow rack piston rod and with the cylinder by sealing rings respectively; wherein the two ends of the cylinder are fastened to piston end cap I and piston end cap II by bolts respectively.

[0011] Preferably, it further includes: a bell-shaped cover and a thrust bearing, wherein the bell-shaped cover has an opening at one end and an open end, and is coaxially mounted on the drive shaft. The end face of the opening is pressed against the end of the output end of the drive shaft by the thrust bearing, and the open end is fixed to the cylinder along with the piston end cover I by bolts.

[0012] Preferably, an axial space is reserved between the opening end of the bell-shaped cover and the end of the hollow rack piston rod, which serves as the effective stroke for the hollow rack piston rod to perform free linear motion.

[0013] Preferably, the hollow rack piston rod has a plurality of U-shaped grooves evenly distributed circumferentially at one axial end, and a serrated strip is provided on one side of each U-shaped groove. All the serrated strips are evenly distributed circumferentially along the hollow rack piston rod. The root of the turbine blade is a gear shaft structure. The turbine blade passes through the U-shaped groove on the hollow rack piston rod and is inserted into the corresponding mounting hole on the input end of the transmission shaft. The gear shaft at the root of the turbine blade and the serrated strip at the end of the hollow rack piston rod form a gear pair transmission engagement.

[0014] Preferably, a retaining ring is provided coaxially at the root of the turbine blade to limit the axial movement of the turbine blade.

[0015] Beneficial effects:

[0016] 1. The pitch control mechanism of this invention achieves the following breakthroughs in the pitch control mechanism of turbine blades in energy conversion equipment that currently employs turbine energy capture input and hydraulic energy storage output:

[0017] (1) The pitch adjustment mechanism of the present invention uses hollow rack piston rod and turbine blades to achieve pitch adjustment. After assembly, the drive shaft, hollow rack piston rod and turbine blades can be integrated into one unit, which reduces the number of pitch adjustment actuators and makes the structure compact.

[0018] (2) At the same time, the present invention utilizes the transmission shaft and hollow rack piston rod to cooperate with multiple turbine blades, which solves the problem of difficult synchronous adjustment of turbine blades. The device is entirely implemented by mechanical structure, which is simple to operate and highly reliable. The mechanism uses a hydraulic system as a power source to achieve precise adjustment of the pitch angle.

[0019] 2. The present invention divides the cavity between the hollow rack piston rod and the cylinder into two oil chambers by piston end cap I, piston end cap II and a shoulder set in the axial middle of the hollow rack piston rod. The two oil chambers cooperate with the hydraulic system to achieve precise adjustment of the paddle pitch angle.

[0020] 3. The present invention provides a bell-shaped cover between the output end of the transmission shaft and the hollow rack piston rod, which can effectively prevent the hollow rack piston rod from hitting the end of the transmission shaft output end during linear movement, thus avoiding damage to the transmission shaft, and also facilitates the effective stroke for the linear movement of the hollow rack piston rod.

[0021] 4. The hollow rack piston rod of the present invention has multiple U-shaped grooves with serrated teeth at one end, which form a gear pair transmission with the gear shaft at the root of the turbine blade, so that when the hollow rack piston rod moves in a straight line, it can synchronously drive the turbine blade to rotate. Attached Figure Description

[0022] Figure 1 This is a three-dimensional structural schematic diagram of the variable pitch mechanism of the present invention.

[0023] Figure 2 This is a right view of the pitch-changing mechanism of the present invention.

[0024] Figure 3 for Figure 2 AA section view in the image.

[0025] Figure 4 This is a schematic diagram of the hollow rack and pinion piston rod of the present invention.

[0026] Figure 5 This is a schematic diagram of the turbine blade of the present invention.

[0027] Figure 6 This is a schematic diagram showing the fit between the hollow rack piston rod and the blades of the present invention.

[0028] Among them, 1-drive shaft, 2-thrust bearing, 3-bell cover, 4-piston end cap I, 5-radial support bearing I, 6-cylinder, 7-hollow rack piston rod, 8-radial support bearing II, 9-turbine blade, 10-retaining ring, 11-piston end cap II. Detailed Implementation

[0029] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0030] This embodiment provides a turbine energy capture hydraulic pitch variable mechanism for underwater turbine energy capture equipment. It uses a hydraulic system to control and drive the turbine blades to achieve pitch variable, which solves the problem of complex turbine blade pitch variable mechanism in current energy conversion equipment that uses turbine energy capture input and hydraulic energy storage output.

[0031] like Figure 1-3 As shown, the pitch control mechanism includes: a drive shaft 1, a thrust bearing 2, a bell-shaped cover 3, a piston end cap I4, a radial support bearing I5, a cylinder 6, a hollow rack piston rod 7, a radial support bearing II8, a turbine blade 9, a retaining ring 10, and a piston end cap II11.

[0032] like Figure 4 As shown, the hollow rack piston rod 7 is a hollow rod-shaped structure, coaxially mounted on the drive shaft 1. The hollow rack piston rod 7 can move linearly relative to the drive shaft 1. The axial ends of the hollow rack piston rod 7 are supported in the cylinder 6 by radial support bearings I5 and II8, respectively, to facilitate the rotational movement of the hollow rack piston rod 7 together with the turbine blade 9 located at one axial end. The axial end of the hollow rack piston rod 7 has multiple (three or more) U-shaped grooves evenly distributed circumferentially, and each U-shaped groove has a serrated edge on one side. All the serrated edges are evenly distributed circumferentially along the hollow rack piston rod 7. Figure 5 As shown, the root of turbine blade 9 is a gear shaft structure, as... Figure 6 As shown, the turbine blade 9 passes through the U-shaped groove on the hollow rack piston rod 7 and is inserted into the corresponding mounting hole on the input end of the transmission shaft 1. The gear shaft at the root of the turbine blade 9 and the serrated rack at the end of the hollow rack piston rod 7 form a gear pair transmission engagement. When the hollow rack piston rod 7 moves in a straight line, it can synchronously drive the turbine blade 9 to rotate.

[0033] The hollow rack piston rod 7 has a shoulder at its axial center. The cylinder 6 is coaxially mounted on the hollow rack piston rod 7, and the inner wall of the cylinder 6 is sealed to the shoulder of the hollow rack piston rod 7 by a sealing ring. Piston end caps I4 and II11 are coaxially mounted on both ends of the hollow rack piston rod 7 and abut against both ends of the cylinder 6. Piston end caps I4 and II11 are sealed to the hollow rack piston rod 7 and to the cylinder 6 by sealing rings. 4. The hollow rack piston rod 7, piston end cap II11, cylinder 6, and sealing ring together form a double-rod hydraulic cylinder structure. This double-rod hydraulic cylinder structure has two oil chambers (chamber A and chamber B), each with an oil port. Both oil ports (port A and port B) are connected to the hydraulic system, thus facilitating the use of the hydraulic system to drive the hollow rack piston rod 7 to reciprocate linearly along the transmission shaft 1. The cylinder 6 is fastened to the piston end cap I4 and piston end cap II11 at both ends by bolts.

[0034] The bell-shaped cover 3 has an opening at one end and an open end at the other. It is coaxially mounted on the transmission shaft 1. The end face of the opening is pressed against the end of the output end of the transmission shaft 1 by the thrust bearing 2 (to prevent the axial clearance of the transmission shaft 1 from moving). The open end is fixed to the cylinder 6 together with the piston end cover I4 by bolts. Sufficient space is reserved axially between the opening end of the bell-shaped cover 3 and the end of the hollow rack piston rod 7 so that the hollow rack piston rod 7 can move freely in a straight line within the effective stroke.

[0035] In this embodiment, a retaining ring 10 is coaxially provided at the root of the turbine blade 9 to limit the axial movement of the turbine blade 9 and prevent the turbine blade 9 from coming out of the mounting hole.

[0036] The working principle of this pitch-changing mechanism is as follows:

[0037] When the water flow drives the turbine blades 9 to rotate circumferentially, the turbine blades 9 drive the hollow rack piston rod 7 and the drive shaft 1 to rotate together, and the output end of the drive shaft 1 can output energy. When it is necessary to increase the pitch angle, the pressure oil is connected to port B, and the hollow rack piston rod 7 moves to the left (in the direction of the output end of the drive shaft 1). Since the hollow rack piston rod 7 and the turbine blades 9 form a gear pair transmission, the hollow rack piston rod 7 simultaneously drives multiple turbine blades 9 to rotate synchronously in the forward direction, thus increasing the pitch angle. When it is necessary to decrease the pitch angle, the pressure oil is connected to port A, and the hollow rack piston rod 7 moves to the right in a straight line. The hollow rack piston rod 7 also simultaneously drives multiple turbine blades 9 to rotate synchronously in the opposite direction, thus decreasing the pitch angle.

[0038] In addition, since the liquid in chambers A and B at both ends of the hollow rack piston rod 7 is hydraulic oil, and hydraulic oil is incompressible, the hollow rack piston rod 7 can effectively lock the turbine blades 9 in both the axial and circumferential directions.

[0039] In summary, the above are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A turbine energy capture hydraulic pitch mechanism, characterized in that, include: Drive shaft (1), radial support bearing I (5), cylinder (6), hollow rack piston rod (7), radial support bearing II (8), turbine blade (9), piston end cap I (4), piston end cap II (11), bell cover (3) and thrust bearing (2); The hollow rack piston rod (7) is a hollow rod-shaped structure, coaxially mounted on the transmission shaft (1), and supported in the cylinder (6) by radial support bearing I (5) and radial support bearing II (8); the hollow rack piston rod (7) has a shoulder in the axial middle part, which divides the cavity between the hollow rack piston rod (7) and the cylinder (6) into two oil chambers; the inner wall of the cylinder (6) and the shoulder of the hollow rack piston rod (7) are sealed by a sealing ring; piston end cap I (4) and piston end cap II (11) are coaxially mounted on both ends of the hollow rack piston rod (7) and abut against both ends of the cylinder (6). The piston end cap I (4) and piston end cap II (11) are sealed with the hollow rack piston rod (7) and the piston end cap I (4) and piston end cap II (11) are sealed with the cylinder (6) by sealing rings respectively. The two ends of the cylinder (6) are fastened to the piston end cap I (4) and piston end cap II (11) by bolts respectively. The bell-shaped cover (3) has an opening at one end and an opening at the other end. It is coaxially mounted on the transmission shaft (1). The end face of the opening is pressed against the end of the output end of the transmission shaft (1) by the thrust bearing (2). The opening end is fixed to the cylinder (6) together with the piston end cover I (4) by bolts. Multiple turbine blades (9) are installed at the input end of the transmission shaft (1) and form a gear pair transmission with the U-shaped groove on the hollow rack piston rod (7) corresponding to the input end of the transmission shaft (1); the hollow rack piston rod (7) and the cylinder (6) form two oil chambers, both of which are connected to the hydraulic system. By inputting pressurized oil into different oil chambers, the hollow rack piston rod (7) is driven to move linearly to the left or right, thereby driving the turbine blades (9) to rotate in the forward or reverse direction; wherein, the forward rotation of the turbine blades (9) increases the pitch angle, and the reverse rotation decreases the pitch angle.

2. The turbine energy harvesting hydraulic pitch mechanism as described in claim 1, characterized in that, The opening end of the bell-shaped cover (3) and the end of the hollow rack piston rod (7) are reserved axially to provide an effective stroke for the hollow rack piston rod (7) to make free linear motion.

3. The turbine energy harvesting hydraulic pitch mechanism as described in claim 1 or 2, characterized in that, The hollow rack piston rod (7) has a plurality of U-shaped grooves evenly distributed circumferentially at one end of its axial direction. Each U-shaped groove has a serrated edge on one side. All the serrated edges are evenly distributed circumferentially along the hollow rack piston rod (7). The root of the turbine blade (9) is a gear shaft structure. The turbine blade (9) passes through the U-shaped groove on the hollow rack piston rod (7) and is inserted into the corresponding mounting hole on the input end of the transmission shaft (1). The gear shaft at the root of the turbine blade (9) and the serrated edge at the end of the hollow rack piston rod (7) form a gear pair transmission engagement.

4. The turbine energy harvesting hydraulic pitch mechanism as described in claim 1 or 2, characterized in that, The root of the turbine blade (9) is provided with a retaining ring (10) to limit the axial movement of the turbine blade (9).

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