Propeller blade and manufacturing method thereof

Abstract

According to the propeller blade and the manufacturing method thereof, the propeller blade comprises a blade body made of a non-metal material, a lattice structure framework made of a metal material is embedded in the blade body, and the overall structure of the lattice structure framework is matched with the structure of the blade body; and the whole propeller blade is manufactured by designing the lattice structure framework, manufacturing the lattice structure framework and performing subsequent processing, so that the blade main body is made of a non-metal material, and the lattice structure framework is made of a metal material and is embedded into the blade main body, the defect that the metal propeller blade is not resistant to corrosion can be avoided, and the service life of the propeller blade is prolonged. And the cost is relatively low.

Description

Technical Field

[0001] The present invention relates to the technical field of propeller blade manufacturing, and particularly to a propeller blade and a manufacturing method thereof. Background Art

[0002] In the prior art, for metal alloy propellers, the metal alloy materials are prone to corrosion, cavitation damage and fatigue failure, resulting in crack generation. With the development of modern ships towards large-scale and high-speed, the high-speed operation of the propeller inevitably leads to cavitation. The shock wave micro-jet generated during the collapse of the cavitation bubble will cause erosion damage to the propeller. The rough and uneven damaged surface will not only reduce the propulsion efficiency of the propeller, but may further exacerbate the erosion of the blade surface. In severe cases, the blade may be perforated, and even the entire blade may be completely damaged and lose its use value. Generally speaking, materials with high hardness have good cavitation resistance. Elastic materials can effectively reduce the impact force due to their good elasticity, have low cavitation stress response characteristics, and can absorb a large amount of energy, but their hardness is relatively low.

[0003] For composite material propellers, they have many advantages that metal propellers do not have. They can be combined with more potential cavitation-resistant materials and have better acoustic characteristics. However, composite materials need to be used, and compared with general materials, composite materials have the problem of complex processing procedures, and high-performance composite materials such as carbon fiber are also very expensive. Summary of the Invention

[0004] The purpose of the present invention is to provide a propeller blade and a manufacturing method thereof to solve the problems existing in the above prior art. The blade body is made of non-metallic materials, and the lattice structure skeleton is made of metal materials and embedded inside the blade body, which can not only avoid the defect of poor corrosion resistance of metal propeller blades, but also have a relatively low cost.

[0005] To achieve the above purpose, the present invention provides the following solution: The present invention provides a propeller blade, including a blade body made of non-metallic materials, and a lattice structure skeleton made of metal materials is embedded inside the blade body, and the overall structure of the lattice structure skeleton matches the structure of the blade body.

[0006] A manufacturing method for the propeller blade is also provided, including the following steps:

[0007] S1. Design the lattice structure skeleton: Obtain the external geometric features of the blade body to be prepared, design the lattice structure skeleton embedded in the blade body, and determine the design domain required for the lattice structure skeleton inside the blade body;

[0008] S2. Fabricate the lattice structure skeleton: Prepare a support component for additive manufacturing, determine the relative position between the support component and the lattice structure skeleton, and after determining the positional relationship between the lattice skeleton and the support component, perform layer-by-layer printing along a certain direction until the fabrication of the lattice structure skeleton is completed;

[0009] S3. Subsequent processing: Separate the lattice structure skeleton from the support component, prepare a metal material for fabricating the blade body, and use the metal material to cast and fabricate the blade body by transfer molding, such that the cast blade body wraps around the lattice structure skeleton.

[0010] Preferably, in step S1, one side surface of the blade body facing the forward direction is the first surface, and the side surface facing away from the forward direction is the second surface. The minimum distance between each of the first surface and the second surface and the lattice structure skeleton is d. The design domain of the lattice structure skeleton is the set of points whose distances to the first surface and the second surface are both greater than or equal to d.

[0011] Preferably, in step S1, there is an auxiliary surface inside the blade body that is equidistant from the first surface and the second surface, and this auxiliary surface serves as the design domain of the lattice structure skeleton.

[0012] Preferably, the support component includes a substrate. When additive manufacturing the lattice structure skeleton in step S2, keep the position of the substrate parallel to the axis of the blade body.

[0013] Preferably, in step S2, the substrate supports the side of the lattice structure skeleton where the structure is relatively dense.

[0014] Preferably, in step S2, a plurality of support rods are evenly connected between the structure of the lattice structure skeleton that is not in the plane of the substrate and the substrate.

[0015] Preferably, in step S2, after determining the positional relationship between the lattice structure skeleton and the substrate, select the required printing equipment and print the lattice structure skeleton layer by layer along the required direction. The relative positional relationship between the wire feeding tube and the print head of the printing equipment determines the printing direction.

[0016] Preferably, in step S3, before casting and fabricating the blade body, first manufacture a mold according to the geometric parameters of the blade body and the required machining allowance. Before casting, position and place the fabricated lattice structure skeleton in the cavity of the mold, start casting the metal material, and after the metal material is completely cured, disassemble the mold and take out the blank of the blade body embedded with the lattice structure skeleton.

[0017] Preferably, after step S3 is completed, a numerical control machine tool is used to process the blank to complete the final manufacturing of the blade body.

[0018] The present invention has achieved the following technical effects compared with the prior art:

[0019] The present invention uses a non-metallic material that is more resistant to cavitation to replace the metal material in the prior art as the blade body, enabling the blade body to have better cavitation resistance. Combined with the lattice structure framework made of metal material, the enhancement effect on the blade body is achieved, and there is no need to use reinforcing fibers, etc., avoiding the problems of complex composite material processing technology and insufficient interlaminar shear strength, making the entire propeller blade disclosed in the present invention more cost-effective. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0021] Figure 1 It is a schematic structural diagram of a propeller formed by combining propeller blades in an embodiment of the present invention;

[0022] Figure 2 It is a schematic diagram of the lattice reinforcement structure design domain in an embodiment of the present invention;

[0023] Figure 3 It is a schematic structural diagram of a propeller blade in an embodiment of the present invention;

[0024] Among them, 1 - lattice structure framework, 2 - blade body. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0025] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0026] The purpose of the present invention is to provide a propeller blade and its manufacturing method to solve the problems existing in the above-mentioned prior art. The blade body is made of a non-metallic material, and the lattice structure framework is made of a metal material and embedded inside the blade body, which can not only avoid the defect of non-corrosion resistance of metal propeller blades but also have a relatively low cost.

[0027] In order to make the above objects, features, and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0028] As Figures 1 to 3 shown, this embodiment provides a propeller blade, which includes a blade body 2 made of a non-metallic material. Preferably, the non-metallic material includes, but is not limited to, resin polymers, etc. When the entire propeller blade is working, the blade body 2 is in direct contact with the water body, and the advantage of the strong cavitation resistance of the non-metallic material can be exerted. A lattice structure framework 1 made of a metallic material is embedded inside the blade body 2. Preferably, the metallic material includes, but is not limited to, stainless steel materials, etc. The lattice structure framework 1 can bear the load and play a role in enhancing the overall structure of the blade body 2, and the overall structure of the lattice structure framework 1 matches the structure of the blade body 2, fully ensuring the strength of the entire blade body 2. The present invention uses a non-metallic material with better cavitation resistance to replace the metallic material in the prior art as the blade body 2, so that the blade body 2 can have better cavitation resistance, and combines the lattice structure framework 1 made of a metallic material to achieve the enhancement effect on the blade body 2, and there is no need to use reinforcing fibers, etc., avoiding the problems of complex composite processing technology and insufficient interlaminar shear strength, making the entire propeller blade disclosed in the present invention more cost-effective.

[0029] Furthermore, a manufacturing method for the propeller blade is also provided, including the following steps:

[0030] S1. Design the lattice structure framework 1: Obtain the external geometric features of the blade body 2 to be prepared, design the lattice structure framework 1 embedded in the blade body 2, and determine the design domain required for the lattice structure framework 1 inside the blade body 2, so that after the design domain is determined, the lattice structure framework 1 with high specific stiffness and high specific strength can be used to fill this design domain later to complete the preliminary design of the lattice structure framework 1;

[0031] S2. Manufacture the lattice structure framework 1: Prepare a support component for additive manufacturing, determine the relative position between the support component and the lattice structure framework 1, and after determining the positional relationship between the lattice framework and the support component, layer by layer printing is carried out along a certain direction until the manufacture of the lattice structure framework 1 is completed. Preferably, the arc additive manufacturing technology is used for manufacturing, and the welding wire uses austenitic stainless steel with good welding performance and mechanical properties;

[0032] S3. Subsequent processing: Separate the lattice structure framework 1 from the support component, preferably by wire cutting to minimize damage to the lattice structure framework 1. Prepare the polymer for manufacturing the blade body 2, and use the polymer to cast and manufacture the blade body 2 by transfer molding, so that the cast blade body 2 wraps around the lattice structure framework 1 to finally obtain a blank of the blade body 2 embedded with the lattice structure framework 1.

[0033] In a specific embodiment, in step S1, one side surface of the blade body 2 facing the forward direction is the first surface, and the side surface facing away from the forward direction is the second surface. The minimum distance between the first surface and the second surface and the lattice structure framework 1 is d. The design domain of the lattice structure framework 1 is the set of points whose distances to the first surface and the second surface are both greater than or equal to d, so as to ensure that in subsequent processing, the lattice structure framework 1 is not easily exposed from the blade body 2. As another preferred embodiment, in step S1, the blade body 2 has an auxiliary surface that is equidistant from the first surface and the second surface. For the area with a small distance between the first surface and the second surface, the auxiliary surface serves as the design domain of the lattice structure framework 1.

[0034] In a specific embodiment, the support component includes a substrate. Preferably, the substrate is made of austenitic stainless steel with good welding performance and mechanical properties. When additive manufacturing the lattice structure framework 1 in step S2, keep the position of the substrate parallel to the axis of the blade body 2, which can reduce the necessary supports and the number of small-angle rods. As another preferred embodiment, in step S2, the substrate supports the side of the lattice structure framework 1 with a relatively dense structure to avoid interference between the printing device and the structure of the printed lattice structure framework 1 during printing. Further preferably, in step S2, a plurality of support rods are evenly connected between the structure of the lattice structure framework 1 not in the plane of the substrate and the substrate to use the support rods as supports to lift the support nodes of the lattice structure framework 1 not in the plane of the substrate, and separate the lattice structure framework 1 from the support rods during subsequent processing. Further preferably, in step S2, after determining the positional relationship between the lattice structure framework 1 and the substrate, select the required printing device to print the lattice structure framework 1 layer by layer in the required direction. The relative positional relationship between the wire feeding tube and the print head of the printing device determines the printing direction. For example, if the wire feeding tube of the printing device is located on the right side of the print head, it should be printed from left to right.

[0035] In a specific embodiment, in step S3, before casting the blade body 2, a mold is first manufactured according to the geometric parameters of the blade body 2 and the required machining allowance. Before casting, the manufactured lattice structure framework 1 is positioned and placed in the cavity of the mold, and then the polymer is poured. After the polymer is completely cured, the mold is disassembled, and the blank of the blade body 2 embedded with the lattice structure framework 1 is taken out. And after step S3 is completed, the blank is machined using a numerical control machine tool to complete the final manufacture of the blade body 2.

[0036] Adaptations made according to actual needs are all within the protection scope of the present invention.

[0037] It should be noted that for those skilled in the art, obviously the present invention is not limited to the details of the above exemplary embodiments, and without departing from the spirit or basic characteristics of the present invention, the present invention can be implemented in other specific forms. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be embraced within the present invention. Any reference signs in the claims should not be regarded as limiting the claimed claim.

[0038] Specific examples are used in the present invention to elaborate on the principles and implementation manners of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manners and application scopes. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A propeller blade, characterized in that: It comprises a blade body made of non-metallic material, wherein a lattice structure skeleton made of metallic material is embedded in the blade body, and the overall structure of the lattice structure skeleton matches the structure of the blade body.

2. A method for manufacturing a propeller blade according to claim 1, characterized in that: The steps include: S1. Designing a lattice structure skeleton: obtaining external geometric features of a blade body to be prepared, designing the lattice structure skeleton embedded in the blade body, and determining a design domain required for the lattice structure skeleton inside the blade body; S2, making the lattice structure skeleton: preparing a support component for additive manufacturing, determining the relative position of the support component and the lattice structure skeleton, and after determining the positional relationship between the lattice skeleton and the support component, printing layer by layer along a certain direction until the lattice structure skeleton is completed; S3. Subsequent processing: separating the lattice structure skeleton from the supporting assembly, preparing metal material for making the blade body, and using the metal material to cast the blade body by transfer molding, so that the casted blade body is wrapped around the lattice structure skeleton.

3. The method according to claim 2, characterized in that: In step S1, the side surface of the blade body facing the forward direction is the first surface, and the side surface away from the forward direction is the second surface. The minimum distances between the first surface and the second surface and the lattice structure skeleton are both d, and the design domain of the lattice structure skeleton is a set of points whose distances to the first surface and the second surface are greater than or equal to d.

4. The method according to claim 3, characterized in that: In step S1, the blade body has an auxiliary surface inside which is equidistant from the first surface and the second surface, and the auxiliary surface serves as a design domain of the lattice structure skeleton.

5. The method according to claim 2, characterized in that: The support assembly includes a base plate. When the lattice structure skeleton is additively manufactured in step S2, the position of the base plate is kept parallel to the axis of the blade body.

6. The method according to claim 5, characterized in that: In step S2, the substrate is supported on a side of the lattice structure where the skeleton structure is relatively dense.

7. The manufacturing method according to claim 6, characterized in that: In step S2, a plurality of support rods are evenly connected between the structure of the lattice structure framework that is not in the plane where the substrate is located and the substrate.

8. The method according to claim 7, characterized in that: In step S2, after determining the positional relationship between the lattice structure skeleton and the substrate, the required printing device is selected to print out the lattice structure skeleton layer by layer along the required direction. The relative positional relationship between the wire feeding tube of the printing device and the print head of the printing device determines the printing direction.

9. The manufacturing method according to claim 2, characterized in that: In step S3, before casting the blade body, a mold is first manufactured according to the geometric parameters of the blade body and the required processing allowance. Before casting, the manufactured lattice structure skeleton is positioned in the cavity of the mold, and the metal material is started to be cast. After the metal material is completely solidified, the mold is disassembled and the blank of the blade body embedded with the lattice structure skeleton is taken out.

10. The manufacturing method according to claim 9, characterized in that: After step S3 is completed, the blank is processed using a CNC machine tool to complete the final manufacturing of the blade body.

Images