Nozzle adjusting device for water-jet propeller

Abstract

The invention discloses a nozzle adjusting device for a water-jet propeller, the nozzle adjusting device is integrally mounted on the periphery of a basic nozzle of the water-jet propeller, and the nozzle adjusting device comprises a sliding sheet, a straight rod and a telescopic driving mechanism; the multiple sliding pieces are arranged in the circumferential direction of the small end of the basic nozzle, a straight rod is installed on the outer wall of each sliding piece, one end of each straight rod is fixedly connected with the corresponding sliding piece, the other end of each straight rod extends towards the large end of the basic nozzle and is connected with the output end of the telescopic driving mechanism, and the telescopic driving mechanism is installed at the large end of the basic nozzle. The telescopic driving mechanism drives the straight rod to move along the wall face of the basic nozzle, and then the sliding piece is driven to slide along the wall face of the basic nozzle, so that synchronous adjustment of the size and the length of the nozzle is achieved. According to the invention, double adjustment of extension and convergence can be realized, the area is changed, the nozzle length is increased, and the conversion efficiency is improved; and zero obstruction of flow in the nozzle can be realized, namely, all structures are arranged on the outer side of the nozzle, so that the flow resistance in the nozzle is prevented from being increased.

Description

Technical Field

[0001] This invention relates to the field of water jet propulsion technology, and more particularly to a nozzle adjustment device for a water jet propulsion device. Background Technology

[0002] Waterjet propulsion systems are widely used in ship propulsion due to their advantages such as high efficiency at high speeds, good cavitation resistance, and low handling noise. Examples include amphibious vehicles, coastal vessels, and landing craft. During ship navigation, the coordination of main engine load and speed, as well as the maintenance of thrust and efficiency, are extremely important.

[0003] Currently, most waterjet propulsion nozzles on ships are manufactured as a single piece. Because the nozzle outlet size is not adjustable, it cannot meet the different nozzle shape requirements for various operating conditions, such as high-speed cruising and rapid acceleration at low speeds. The following are some current methods for adjusting waterjet propulsion nozzles: (1) Two symmetrical hydraulic cylinders are arranged on the outer wall of the nozzle to push the sleeve to extend and retract along the axial direction to adjust the length, and control the angle of the swing blade to adjust the size of the outlet cross-sectional area; (2) Blade swing / rotation type vector nozzle, a swingable blade is set in the nozzle outlet section. The blade is driven by a hydraulic cylinder to rotate around the radial pin shaft to achieve contraction or expansion. At the same time, the hydraulic motor drives the entire blade assembly to rotate around the axis, thereby achieving the change of jet direction at all angles.

[0004] The above adjustment scheme cannot simultaneously adjust both the nozzle area and length; it can only change a single element.

[0005] In addition, existing variable displacement nozzles in other fields are either unable to meet the requirements of underwater navigation nozzles, or the synchronous control of multiple mechanical structures is complex and costly. Summary of the Invention

[0006] The main objective of this invention is to provide a nozzle adjustment device for a waterjet propulsion system. This device can achieve dual adjustment of "extension + convergence," which changes the area and increases the nozzle length to improve conversion efficiency. It can also achieve zero flow obstruction inside the nozzle, meaning that all structures are placed outside the nozzle to avoid increasing flow resistance inside the nozzle.

[0007] The technical solution adopted in this invention is: A nozzle adjustment device for a waterjet propulsion device is integrally installed on the outer periphery of the base nozzle of the waterjet propulsion device. The device includes a sliding vane, a straight rod, and a telescopic drive mechanism. Several sliding vanes are arranged circumferentially along the small end of the base nozzle. A straight rod is installed on the outer wall of each sliding vane. One end of the straight rod is fixedly connected to the sliding vane, and the other end extends towards the large end of the base nozzle and connects to the output end of the telescopic drive mechanism, which is installed at the large end of the base nozzle. The telescopic drive mechanism drives the straight rod to move along the wall of the base nozzle, thereby causing the sliding vanes to slide along the wall of the base nozzle to achieve synchronous adjustment of the nozzle size and length.

[0008] In the above scheme, there is a gap between adjacent sliding plates in the fully contracted state; in the fully extended state, adjacent sliding plates are tightly connected.

[0009] In the above scheme, in the fully retracted state, the small end of the sliding vane is flush with the small end of the base nozzle.

[0010] In the above scheme, the telescopic drive mechanism includes a fixed ring frame, a drive gear, a pin-driven gear, a cam internal gear, and a tie rod. The fixed ring frame is fixedly installed on the outer periphery of the large end of the base nozzle. The drive gear is installed on the outside of the fixed ring frame and driven by a motor. The pin-driven gear is installed on the fixed ring frame and includes a main tooth and a pin tooth. The main tooth meshes with the drive gear, and the pin tooth extends axially and is spaced apart along the circumference of the pin-driven gear. The cam internal gears are arranged along the circumference of the pin-driven gears, and their number is the same as the number of sliding vanes. The axial direction of the cam internal gears is parallel to the tangent of the base nozzle, and the cam internal gears mesh with the pin teeth of the pin-driven gears. A tie rod is installed on each cam internal gear. One end of the tie rod is hinged to the cam internal gear, and the other end is hinged to the straight rod.

[0011] In the above scheme, the fixed ring frame includes a column and a ring structure. The inner end of the column is fixedly connected to the base nozzle, and the outer end is fixedly connected to the ring structure. The ring structure has a cavity for installing the main tooth. The main tooth is installed in the cavity of the ring structure. The rear end face of the ring structure has an annular groove, and the pin tooth extends out of the groove axially.

[0012] In the above scheme, the nozzle adjustment device also includes a limiter that corresponds to the straight rod. The limiter is fixedly installed on the outer wall of the base nozzle and has a cavity for the straight rod to pass through.

[0013] In the above scheme, a linear bearing is provided between the inner wall of the cavity of the limiter and the straight rod.

[0014] In the above scheme, the nozzle adjustment device further includes several support structures arranged circumferentially along the base nozzle. The support structures are fixedly installed on the outer wall of the base nozzle. Each support structure extends along the sliding direction of the sliding plate and is located on the inner side of the sliding plate to provide support force.

[0015] The present invention also proposes a water jet propulsion device, including a base nozzle, a hub and rectifier blades, wherein the hub and rectifier blades are disposed inside the base nozzle, and the present invention also includes the above-mentioned nozzle adjustment device.

[0016] In the above scheme, the outer wall of the small end of the basic nozzle is a slope, and the wall thickness between the outer wall and the inner wall of the small end decreases from back to front.

[0017] The beneficial effects of this invention are: 1. The nozzle adjustment device of the present invention enables the adjustment of the nozzle outlet size and length within a certain range, so that the nozzle outlet flow velocity is always kept in the "optimal kinetic energy conversion range", which expands the range of working conditions and solves the problems of single navigation efficiency and inability to adapt to the different requirements of the thrust of the ejected water flow during rapid braking at sea.

[0018] 2. The nozzle adjustment device of the present invention is located on the outer wall of the nozzle. It will not damage the original nozzle shape during operation and will not obstruct the flow of fluid inside the nozzle. Maintenance does not require disassembling the basic nozzle itself, which shortens maintenance time. This solution has good economic efficiency and is easy to operate. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the overall structure of the nozzle adjustment device for a water jet propulsion system according to the present invention; Figure 2 This is a schematic diagram of the basic nozzle structure; Figure 3 This is an assembly diagram of the nozzle adjustment device and the basic nozzle for a water jet propulsion device according to the present invention; Figure 4 yes Figure 3 Another perspective illustration; Figure 5 This is a schematic diagram of the nozzle adjustment device in its fully retracted state. Figure 6This is a schematic diagram of the nozzle adjustment device in its fully extended state. Figure 7 This is an enlarged view of a portion of the structure of the driven gear with pin and the internal gear of the cam in the nozzle adjustment device; Figure 8 This is a cross-sectional view of the linear bearing inside the limit switch. Figure 9 This is a schematic diagram showing the connection between the nozzle adjustment device and the impeller and flow channel of the water jet propulsion unit; Figure 10 This is a structural cross-sectional view of the basic nozzle.

[0021] In the diagram: 100, nozzle adjustment device; 10. Sliding slide; 20. Straight rod; 30. Limiter; 31. Linear bearing; 40. Telescopic drive mechanism; 41. Fixed ring frame; 411. Column; 412. Ring structure; 42. Driving gear; 43. Driven gear with pin; 431. Main gear; 432. Pin tooth; 44. Cam internal gear; 45. Tie rod; 46. Cylindrical pin; 50. Support structure; 200. Basic nozzle; 201. Hub; 202. Rectifier blades; 300. Impeller casing; 400. Water inlet channel. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0023] It should be noted that the illustrations provided in the embodiments of the present invention are only schematic representations of the basic concept of the present invention. Therefore, the drawings only show the components related to the present invention and are not drawn according to the number, shape and size of the components in actual implementation. In actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0024] In this invention, it should also be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first" and "second" are used only for descriptive and distinguishing purposes and should not be construed as indicating or implying relative importance.

[0025] like Figure 1 As shown, this invention proposes a nozzle adjustment device 100 for a waterjet propulsion system, comprising a sliding vane 10, a straight rod 20, and a telescopic drive mechanism 40. The structure of the basic nozzle 200 of the waterjet propulsion system is as follows: Figure 2 As shown, Figure 3-4 As shown, the nozzle adjustment device 100 is integrally installed on the outer periphery of the base nozzle 200 of the water jet propulsion device. Several sliding vanes 10 are evenly arranged circumferentially along the small end of the base nozzle 200. A straight rod 20 is installed on the outer wall of each sliding vane 10. One end of the straight rod 20 is fixedly connected to the sliding vane 10, and the other end extends towards the large end of the base nozzle 200 and connects to the output end of the telescopic drive mechanism 40, which is installed at the large end of the base nozzle 200. The telescopic drive mechanism 40 drives the straight rod 20 to move back and forth along the wall of the base nozzle 200, thereby causing the sliding vanes 10 to slide back and forth along the wall of the base nozzle 200 to achieve synchronous adjustment of the nozzle size and length.

[0026] It should be noted that the directions described in this patent are defined as follows: "inside and outside" refers to the radial direction of the base nozzle 200, with the direction closer to the central axis of the base nozzle 200 being "inside" and the direction farther from the central axis of the base nozzle 200 being "outside"; "front and back" refers to the axial direction of the base nozzle 200, with the direction closer to the small end of the base nozzle 200 being "front" and the direction farther from the small end of the base nozzle 200 being "back".

[0027] like Figure 5 As shown, in the fully retracted state, the small end of the sliding vane 10 is flush with the small end of the base nozzle 200, and there is a gap between adjacent sliding vanes 10. Figure 6 As shown, in the fully extended state, adjacent sliding pieces 10 are closely connected to form the side of a frustum.

[0028] In this embodiment, the number of sliding sliders 10 is 6. In other embodiments, the number of sliding sliders 10 can be adjusted as needed. The present invention does not limit the number of sliding sliders 10.

[0029] like Figure 7As shown, the telescopic drive mechanism 40 includes a fixed ring frame 41, a driving gear 42, a pin-driven gear 43, a cam internal gear 44, and a pull rod 45. The fixed ring frame 41 is fixedly installed on the outer periphery of the large end of the base nozzle 200 and is coaxially arranged with the base nozzle 200. The fixed ring frame 41 includes a column 411 and a ring structure 412. The inner end of the column 411 is fixedly connected to the base nozzle 200, and the outer end is fixedly connected to the ring structure 412. The driving gear 42 is installed on the outer side of the fixed ring frame 41 and is driven by a motor. The driven gear 43 includes a main tooth 431 and a pin tooth 432. The driven gear 43 is mounted on a fixed ring frame 41. Specifically, a cavity for mounting the main tooth 431 is provided within the annular structure 412. The main tooth 431 is mounted within the cavity of the annular structure 412 and meshes with the driving gear 42. An annular groove is provided on the rear end face of the annular structure 412. The pin tooth 432 extends axially out of the groove and is spaced apart along the circumference of the driven gear 43. The number of cam internal gears 44 is the same as the number of sliding vanes 10 and corresponds one-to-one with the sliding vanes 10. The cam internal gears 44 are evenly arranged along the circumference of the driven gear 43. The axial direction of the cam internal gears 44 is parallel to the tangent of the base nozzle 200. The cam internal gears 44 mesh with the pin teeth 432 of the driven gear 43. A pull rod 45 is installed on each cam internal gear 44, with one end of the pull rod 45 hinged to the cam internal gear 44 and the other end hinged to the straight rod 20.

[0030] The telescopic drive mechanism 40 of this invention has a fixed ring frame 41 and a pin-driven gear 43 coaxially arranged with the base nozzle 200. The axial direction of the drive gear 42 is parallel to the axial direction of the base nozzle 200, and the axial direction of the cam internal gear 44 is parallel to the tangential direction of the base nozzle 200. The working principle is as follows: When the motor rotates forward, it drives the drive gear 42 to rotate, which in turn drives the pin-driven gear 43 to rotate. The pin teeth 432 of the pin-driven gear 43 drive the cam internal gear 44 to rotate around the tangential axis, thereby driving the pull rod 45 to move. The pull rod 45 further drives the straight rod 20 to move forward along the wall of the base nozzle 200, and pushes the sliding plate 10 to slide forward along the wall of the base nozzle 200, achieving a contraction in nozzle area and an extension in length. When the motor rotates in reverse, it ultimately drives the sliding plate 10 to slide backward along the wall of the base nozzle 200, achieving an expansion in nozzle area and a shortening in length.

[0031] The telescopic drive mechanism 40 of the present invention has the following structural design advantages: 1. Multiple sets of cam internal gears 44 correspond one-to-one with the sliding vanes 10 and are evenly distributed circumferentially. All cam internal gears 44 are driven by the same set of driving gears 42 and driven gears 43 with pins, ensuring that power is synchronously transmitted to each straight rod 20. The straight rods 20 and sliding vanes 10 are rigidly fixed, with uniform connecting rod lengths and consistent connection methods, avoiding displacement deviations in a single set of sliding vanes 10, and achieving synchronous extension and retraction of the sliding vanes 10 to accurately form the target cross section.

[0032] 2. All moving parts are concentrated on the outer wall of the nozzle to avoid direct contact with the internal fluid, reduce the risk of corrosion and impurity blockage, and ensure long-term operational stability.

[0033] 3. After the sliding vane 10 extends synchronously, it forms an "extended nozzle of the original nozzle". Compared with other structures that control the outflow size, it is more in line with the diffusion trend of water flowing out of the nozzle, reduces the turbulence of water flow at the outlet end, and further optimizes the flow field distribution and improves the kinetic energy conversion efficiency in conjunction with the angle gradient of the basic nozzle 200.

[0034] 4. The rigid fixation of the straight rod 20 and the sliding plate 10 allows the pushing and pulling force of the straight rod 20 to be directly and without loss to the sliding plate 10. At the same time, when the sliding plate 10 is subjected to water pressure, the load can be distributed to the limiter 30 and the fixed ring frame 41 through the straight rod 20, avoiding damage to a single component due to overload and improving the overall load resistance.

[0035] Further optimization involves hinged connection between the pull rod 45 and the straight rod 20 via a cylindrical pin 46.

[0036] like Figure 8 As shown, the nozzle adjustment device 100 also includes limiters 30 corresponding to the straight rods 20. The limiters 30 are fixedly installed on the outer wall of the base nozzle 200, and each limiter 30 has a cavity for the straight rod 20 to pass through. The function of the limiters 30 is to provide a force perpendicular to the wall of the base nozzle 200 to the straight rod 20, so that the straight rod 20 can only move back and forth along the outer wall of the base nozzle 200, thus ensuring its stability.

[0037] To further optimize the design, a linear bearing 31 is provided between the inner wall of the cavity of the limiter 30 and the straight rod 20, which can change the sliding friction of the straight rod 20 into rolling friction and reduce wear.

[0038] Further optimization involves fixing the limiter 30 near the retraction limit position of the sliding slide 10.

[0039] In a further optimization, the nozzle adjustment device 100 also includes a support structure 50, which is fixedly installed on the outer wall of the base nozzle 200. The support structure 50 is located inside the sliding vane 10 to provide support force and can reduce vibration during extension.

[0040] In this embodiment, two symmetrical support structures 50 are provided on the inner side of each sliding slide 10.

[0041] Accordingly, the present invention also proposes a waterjet propulsion device, including a base nozzle 200, a hub 201, and rectifier blades 202, wherein the hub 201 and rectifier blades 202 are disposed inside the base nozzle 200, and further including the aforementioned nozzle adjustment device 100, which is integrally mounted on the outer periphery of the base nozzle 200 of the waterjet propulsion device. Figure 9 As shown, the large end of the base nozzle 200 is connected to the impeller housing 300 and the water inlet channel 400 in sequence.

[0042] The water flow gradually becomes more even after passing through the original nozzle. To better concentrate the thrust, such as... Figure 10 As shown, the outer wall of the small end of the basic nozzle 200 is inclined, and the wall thickness between the outer and inner walls of the small end decreases from the large end to the small end. By increasing the wall thickness of the basic nozzle 200 at an angle, the exit cross-sectional area when the sliding vane 10 is fully lowered to the far end is smaller than the exit cross-sectional area when lowered along the original nozzle trajectory, thus exacerbating the area shrinkage. The exit area of ​​the sliding vane 10 when fully extended to the far end can shrink by 50% relative to the original nozzle exit area.

[0043] It should be noted that, depending on the implementation needs, the various steps / components described in this application can be broken down into more steps / components, or two or more steps / components or parts of the operation of steps / components can be combined into new steps / components to achieve the purpose of this invention.

[0044] The order of the steps in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0045] It should be understood that those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A nozzle adjustment device for a waterjet propulsion system, characterized in that, The nozzle adjustment device is integrally installed on the outer periphery of the base nozzle of the water jet propulsion device, and includes a sliding vane, a straight rod and a telescopic drive mechanism; Several sliding vanes are arranged circumferentially along the small end of the basic nozzle. A straight rod is installed on the outer wall of each sliding vane. One end of the straight rod is fixedly connected to the sliding vane, and the other end extends toward the large end of the basic nozzle and is connected to the output end of the telescopic drive mechanism. The telescopic drive mechanism is installed at the large end of the basic nozzle. The telescopic drive mechanism moves the straight rod along the wall of the base nozzle, thereby causing the sliding vane to slide along the wall of the base nozzle to achieve synchronous adjustment of the nozzle size and length.

2. The nozzle adjustment device for a waterjet propulsion device according to claim 1, characterized in that, In the fully contracted state, there is a gap between adjacent sliding plates; in the fully extended state, adjacent sliding plates are tightly connected.

3. The nozzle adjustment device for a waterjet propulsion system according to claim 2, characterized in that, In the fully retracted state, the small end of the sliding vane is flush with the small end of the base nozzle.

4. The nozzle adjustment device for a waterjet propulsion system according to claim 1, characterized in that, The telescopic drive mechanism includes a fixed ring frame, a drive gear, a pin-driven gear, a cam internal gear, and a tie rod. The fixed ring frame is fixedly installed on the outer periphery of the large end of the base nozzle. The drive gear is installed on the outside of the fixed ring frame and driven by a motor. The pin-driven gear is installed on the fixed ring frame and includes a main tooth and a pin tooth. The main tooth meshes with the drive gear, and the pin tooth extends axially and is spaced apart along the circumference of the pin-driven gear. The cam internal gears are arranged along the circumference of the pin-driven gears, and their number is the same as the number of sliding vanes. The axial direction of the cam internal gears is parallel to the tangent of the base nozzle, and the cam internal gears mesh with the pin teeth of the pin-driven gears. A tie rod is installed on each cam internal gear, with one end of the tie rod hinged to the cam internal gear and the other end hinged to the straight rod.

5. The nozzle adjustment device for a waterjet propulsion system according to claim 4, characterized in that, The fixed ring frame includes a column and a ring structure. The inner end of the column is fixedly connected to the base nozzle, and the outer end is fixedly connected to the ring structure. The ring structure has a cavity for installing the main tooth. The main tooth is installed in the cavity of the ring structure. The rear end face of the ring structure has an annular groove, and the pin tooth extends out of the groove axially.

6. The nozzle adjustment device for a waterjet propulsion device according to claim 1, characterized in that, The nozzle adjustment device also includes a limiter that corresponds to the straight rod. The limiter is fixedly installed on the outer wall of the base nozzle and has a cavity for the straight rod to pass through.

7. The nozzle adjustment device for a waterjet propulsion system according to claim 6, characterized in that, A linear bearing is provided between the inner wall of the cavity of the limiter and the straight rod.

8. The nozzle adjustment device for a waterjet propulsion system according to claim 1, characterized in that, The nozzle adjustment device also includes several support structures arranged circumferentially along the base nozzle. The support structures are fixedly installed on the outer wall of the base nozzle. Each support structure extends along the sliding direction of the sliding plate and is located on the inner side of the sliding plate to provide support force.

9. A waterjet propulsion device, comprising a base nozzle, a hub, and rectifier blades, wherein the hub and rectifier blades are disposed inside the base nozzle, characterized in that, It also includes the nozzle adjustment device as described in any one of claims 1-8.

10. The waterjet propulsion device according to claim 9, characterized in that, The outer wall of the small end of the basic nozzle is inclined, and the wall thickness between the outer and inner walls of the small end decreases from back to front.

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