Disc type multi-oil-cylinder five-degree-of-freedom loading mechanism

Abstract

The invention discloses a disc-type multi-oil-cylinder five-degree-of-freedom loading mechanism, and belongs to the technical field of mechanical assembly bearing testing. The disc-type multi-oil-cylinder five-degree-of-freedom loading mechanism comprises a supporting base; a loading bracket is arranged on the supporting base; the middle of the loading bracket is used for connecting a tested piece; an axial loading unit and a radial loading unit are respectively arranged on the outer wall of the loading bracket; the axial loading unit and the radial loading unit respectively and independently provide axial force and radial force and transmit the axial force and the radial force to a tested piece through the loading bracket, or provide bending moment in a combined manner and transmit the bending moment to the tested piece through the loading bracket. The disc type multi-oil-cylinder five-degree-of-freedom loading mechanism can effectively solve the problems that a test bed in the prior art can only provide torque needed by a wind power main shaft and cannot truly simulate axial thrust, bending moment and other acting loads of actual wind loads on the main shaft.

Description

Technical Field

[0001] The present invention belongs to the technical field of mechanical component bearing tests. Specifically, it relates to a disc-type multi-cylinder five-degree-of-freedom loading mechanism. Background Art

[0002] "Large scale, long life and high reliability" of wind power equipment are the development trends of the global wind power equipment manufacturing industry and also common technical challenges. The service conditions load of wind power equipment is affected by irregular variable-direction loads, such as wind force and even strong gusts, which can easily cause the failure of key components. According to the wind power equipment failure statistics data at home and abroad in the past decade or so, the failures of megawatt-level wind power equipment mainly concentrate on key components such as gearboxes, fan drive trains, generators, blades, power systems, and yaw systems. Among them, the fan drive train is the key component that causes the longest downtime of wind power equipment. Due to the strict requirements of the wind power equipment technology field for the reliability and life of the fan drive train, bench test of the fan drive train is an important link in the development, design, and production of the fan drive train. Currently, the widely used fan test bench in engineering is a motor-driven reducer directly connected to the wind turbine drive system. This test bench can only provide the torque required by the wind turbine, but cannot truly simulate the other acting loads of the actual wind load on the main shaft. In addition, the input main shaft part of the fan drive train also needs to bear axial thrust and bending moment loads. Summary of the Invention

[0003] The purpose of the present invention is to provide a disc-type multi-cylinder five-degree-of-freedom loading mechanism for the above-mentioned deficiencies, so as to solve the problems that the existing test bench can only provide the torque required by the wind power main shaft and cannot truly simulate the axial thrust and bending moment and other acting loads of the actual wind load on the main shaft. To achieve the above purpose, the present invention provides the following technical solutions:

[0004] A disc-type multi-cylinder five-degree-of-freedom loading mechanism includes a support base; a loading bracket is provided on the support base; the middle of the loading bracket is used to connect the test piece; axial loading units and radial loading units are respectively provided on the outer walls of the loading bracket; the axial loading unit and the radial loading unit respectively provide axial force and radial force alone and transmit them to the test piece through the loading bracket, or provide bending moment in combination and transmit it to the test piece through the loading bracket.

[0005] Further, two axial force-bearing surfaces and radial force-bearing surfaces are provided on the outer wall of the loading bracket; the two groups of axial force-bearing surfaces are symmetrically distributed on both sides of the radial force-bearing surface.

[0006] Further, the axial loading unit includes two groups of axial brackets, which are symmetrically arranged on the two axial force-bearing surfaces; a number of servo cylinders are evenly provided on the two groups of axial brackets, and the servo cylinders on the two groups of axial brackets are symmetrically arranged to respectively provide axial force and transmit it to the two axial force-bearing surfaces.

[0007] Furthermore, the radial loading unit includes a radial support disposed on the radial stress surface; a number of servo cylinders are evenly arranged on the radial support to provide radial force and transmit it to the radial stress surface.

[0008] Furthermore, the servo cylinder includes a cylinder barrel and a piston rod; the cylinder barrel is fixed on the loading support; the piston rod moves telescopically in the cylinder barrel, and a loading assembly is provided at one end of the piston rod; the piston rod transmits the acting force to the radial stress surface or the axial stress surface through the loading assembly.

[0009] Furthermore, the loading assembly includes a ball head seat, a ball head seat gland, and a stress disk; the end of the piston rod is set as a universal ball head that mates with the ball head seat and is connected to the ball head seat through the ball head seat gland; the stress disk is connected to the side of the ball head seat opposite to the universal ball head and contacts the radial stress surface or the axial stress surface.

[0010] Furthermore, a modified PTFE coating is provided on the side of the stress disk that contacts the radial stress surface or the axial stress surface; 15%-25% of carbon fiber and 5%-10% of graphite are added to the modified PTFE coating on the basis of the PTFE coating.

[0011] Furthermore, flange interfaces are provided at both ends of the loading support for fixedly connecting the test piece.

[0012] Furthermore, a tensile and compressive force sensor is provided between the ball head seat and the stress disk.

[0013] Furthermore, a displacement sensor is provided on the servo cylinder for detecting the displacement of the piston rod.

[0014] The beneficial effects of the present invention are as follows:

[0015] A disc-type multi-cylinder five-degree-of-freedom loading mechanism of the present invention can simulate the loading mechanism of actual working conditions. This mechanism can provide radial loading, axial loading, bending moment loading, simultaneous bending moment and axial loading, simultaneous radial and axial loading, simultaneous radial and bending moment loading, and simultaneous radial, axial and bending moment loading separately. This mechanism can provide stable loads or loads that change according to certain rules such as alternating loads, etc., and can conduct load tests according to design requirements and actual working conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a three-dimensional structural schematic diagram of the present invention;

[0017] Figure 2 is a front view of the present invention;

[0018] Figure 3 is Figure 2 a sectional view taken along A-A;

[0019] Figure 4 This is a cross-sectional view of the servo cylinder of the present invention;

[0020] Figure 5 This is a schematic diagram of the position of the servo cylinder;

[0021] In the drawings: 1, axial bracket; 2, servo cylinder; 3, radial bracket; 5, loading bracket; 6, support base; 201, displacement sensor; 202, cylinder barrel; 203, piston rod; 204, ball head seat gland; 205, ball head seat; 206, tension and compression sensor; 207, force-receiving disc; 208, modified PTFE coating. Specific embodiments

[0022] The present invention will be further described in detail below with reference to the drawings and specific embodiments. To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Usually, the components of the embodiments of the present invention described and illustrated herein can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the scope of protection of the present invention.

[0023] It should be noted that like reference numerals and letters denote like items in the following figures. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the figures, or the orientation or positional relationship in which the product of the invention is usually placed during use. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention. In addition, the terms "first", "second", "third", etc. are only used for distinguishing descriptions and should not be construed as indicating or implying relative importance. In addition, terms such as "horizontal" and "vertical" do not mean that the components are required to be absolutely horizontal or hanging vertically, but may be slightly inclined. For example, "horizontal" only means that its direction is more horizontal relative to "vertical", and does not mean that the structure must be completely horizontal, but may be slightly inclined. In the description of the present invention, it should also be noted that unless otherwise clearly specified and limited, the terms "set", "installed", "connected", "connected" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0024] Embodiment:

[0025] As shown in the Figures 1 to 5 accompanying drawings, a disc-type multi-cylinder five-degree-of-freedom loading mechanism includes a support base 6, which is fixedly connected to the ground. A loading bracket 5 is provided on the support base 6. The middle of the loading bracket 5 is connected to the main shaft, and its overall cross-section is circular. A flange interface is provided in the middle of the loading bracket 5 and is fixedly connected to the test piece. Axial loading units and radial loading units are respectively provided on the outer edge of the loading bracket 5, which provide axial force and radial force to the loading bracket 5 respectively, and are transmitted to the test piece through the loading bracket 5 to complete the loading test. Among them, the axial loading unit can be combined with the radial loading unit to provide a bending moment, so as to meet the loading of the bending moment of the test piece.

[0026] The outer edge of the loading bracket 5 is set as a convex disc structure. The symmetric two ends of the convex disc structure are the axial force bearing surfaces, and the side wall is the radial force bearing surface. The axial loading unit includes two groups of axial brackets 1, which are respectively arranged on the outer edge of the loading bracket 5 and symmetrically arranged. A number of servo cylinders 2 are evenly arranged on the circumferential bracket for providing force. Specifically, each group of axial brackets 1 is provided with 24 groups of servo cylinders 2. The servo cylinders 2 on the two groups of axial brackets 1 are arranged symmetrically in pairs. The output ends of the servo cylinders 2 all face the axial force bearing surface. The force is loaded onto the axial force bearing surface through the servo cylinders 2. The servo cylinders 2 on the axial bracket 1 are numbered from 1 to 48. As shown in the appendix Figure 5 As shown, the positions of the servo cylinders 2 numbered 25 to 48 are opposite to those of the servo cylinders 2 numbered 1 to 24.

[0027] The radial loading unit includes a radial bracket 3, which is also arranged at the convex disc structure of the loading bracket 5. A number of groups of servo cylinders 2 are also arranged on the radial bracket 3. In this embodiment, 24 groups of servo cylinders 2 are arranged, which are evenly arranged along the outer edge of the loading bracket 5. The output ends of the servo cylinders 2 on the radial bracket 3 face the radial force bearing surface. By starting the servo cylinders 2 at different positions on the radial bracket 3, radial forces in different directions are output to the loading bracket 5 and transmitted to the test piece. The servo cylinders 2 on the radial bracket 3 are numbered from 49 to 72. As shown in the appendix Figure 5 As shown.

[0028] The servo cylinder 2 includes a cylinder barrel 202 and a piston rod 203. The piston rod 203 is slidably arranged in the cylinder barrel 202, and the piston rod 203 is driven to move by means of hydraulic oil or a servo motor. The end of the piston rod 203 contacts each bearing surface through a loading assembly. The loading assembly includes a ball head seat 205, a ball head seat gland 204 and a force bearing disc 207. The end of the piston rod 203 is provided with a universal ball head in cooperation with the ball head seat 205, and is connected to the ball head seat 205 through the ball head seat gland 204. The ball head seat 205 is fixed on the loading bracket 5. The force bearing disc 207 is arranged on the side of the ball head seat 205 away from the piston rod 203 and contacts the bearing surface. The piston rod 203 transmits the force to the bearing surface of the loading bracket 5 through the universal ball head, the ball head seat 205 and the force bearing disc 207 in sequence, and is transmitted to the test piece through the loading bracket 5. The acting position of the piston rod 203 and the force bearing disc 207 is set as a universal ball head structure. Its force is always on one surface. Compared with using a straight rod structure, its force is on one point. Compared with the contact surface, the pressure received is smaller, which can play a protective role, extend the service life at the same time, or be applicable to tests with greater force. At the same time, the universal ball head structure can avoid the piston rod 203 from being bent due to force under certain conditions, resulting in damage to the piston rod 2, and reducing the service life of the equipment.

[0029] A displacement sensor 201 is provided on the servo cylinder 2 to detect the displacement of the piston rod 203 during operation. An alarm device can be set according to the movement range of the piston rod 203. When the displacement of the piston rod 203 exceeds the range, it indicates that there is a risk of fracture of the piston rod 203 or a fault occurs in the loading component. A tension and compression sensor 206 is provided between the force-receiving disc 207 and the ball head seat 205 to detect the thrust output by the servo cylinder 2.

[0030] On one side of the force-receiving disc 207 in contact with the force-receiving surface, a modified PTFE coating 208 is provided. The modified PTFE coating 208 is added with 15%-25% carbon fiber and 5%-10% graphite on the basis of the PTFE coating, making it have the characteristics of high compressive strength, self-lubrication, wear resistance, high temperature resistance, low friction, etc.

[0031] The servo cylinder 2 is installed around the convex disc structure, so that the axial dimension of the entire loading mechanism will be very short, which can reduce the overall size and space.

[0032] Working process: Place it in the xyz space as shown in the appendix. Figure 5 Shown.

[0033] First, radial loading in the Z direction: The servo cylinder 2 applies a thrust from 56-66, and the other radial servo cylinders 2 do not apply force values; radial loading in the Y direction: The servo cylinder 2 applies a thrust from 62-72, and the other radial servo cylinders 2 do not apply force values; for loading of force values in any other direction, only need to adjust the servo cylinders 2 at different positions to apply thrust according to the loading force direction.

[0034] Second, axial loading: The servo cylinder 2 applies a thrust from 1-24, and the servo cylinders 2 from 25-48 do not apply force values; or the servo cylinder 2 applies a thrust from 28-48, and the servo cylinders 2 from 1-24 do not apply force values.

[0035] Third, bending moment loading in the y direction: The servo cylinder 2 applies a thrust from 8-18, 25-30, 44-48, and the other axial servo cylinders 2 do not apply force values; bending moment loading in the z direction: The servo cylinder 2 applies a thrust from 2-12, 38-48, and the other axial servo cylinders 2 do not apply force values; for bending moment loading in any other direction, only need to adjust the servo cylinders 2 at different positions to apply thrust according to the bending moment direction.

[0036] Fourth, simultaneous radial and axial loading: Just apply force values simultaneously according to the loading methods in Embodiment 1 and Embodiment 2; for example, the servo cylinder 2 from 56-66 applies a thrust, the other radial servo cylinders 2 do not apply force values, the servo cylinder 2 from 1-24 applies a thrust, and the servo cylinders 2 from 25-48 do not apply force values; for simultaneous radial and axial loading in any other direction, only need to adjust the servo cylinders 2 at different positions to apply thrust according to the direction.

[0037] V. Simultaneous radial and bending moment loading: Just apply the force values simultaneously according to the loading methods of Embodiment 1 and Embodiment 3; for example, the servo cylinder 2 of 56 - 66 applies a thrust force, and the other radial servo cylinders 2 do not apply force values. The servo cylinders 2 of 8 - 18, 25 - 30, and 44 - 48 apply thrust forces, and the other axial servo cylinders 2 do not apply force values. For the simultaneous loading of the radial and bending moment in any other direction, just adjust the servo cylinders 2 at different positions to apply thrust forces according to the direction.

[0038] VI. Simultaneous axial and bending moment loading: Just apply the force values simultaneously according to the loading methods of Embodiment 2 and Embodiment 3. It should be noted that the force values applied by each servo cylinder 2 need to be superimposed before loading; for example, the servo cylinders 2 of 1 - 24 apply thrust forces, the servo cylinders 2 of 8 - 18, 25 - 30, and 44 - 48 apply thrust forces, and the other axial servo cylinders 2 do not apply force values. And the servo cylinders 2 of 8 - 18 need to be superimposed and loaded. The sum of the force value generated by applying the axial force and the force value generated by applying the bending moment is the thrust force that needs to be applied in this state.

[0039] Embodiment: Simultaneous radial, axial, and bending moment loading: Just apply the force values simultaneously according to the loading methods of Embodiment 1 and Embodiment 6; for example, the servo cylinder 2 of 56 - 66 applies a thrust force, the other radial servo cylinders 2 do not apply force values, the servo cylinders 2 of 1 - 24 apply thrust forces, the servo cylinders 2 of 8 - 18, 25 - 30, and 44 - 48 apply thrust forces, and the other axial servo cylinders 2 do not apply force values. For the simultaneous loading of the radial, axial, and bending moment in any other direction, just adjust the servo cylinders 2 at different positions to apply thrust forces according to the direction.

[0040] The above are only the preferred embodiments of the present invention, and do not limit the patent scope of the present invention accordingly. Any equivalent structural or equivalent process transformation made by using the description and drawings of the present invention, or directly or indirectly applied in other related technical fields, shall be equally included in the patent protection scope of the present invention.

Claims

1. A disc-type multi-cylinder five-degree-of-freedom loading mechanism, characterized in that: It includes a support base (6); a loading bracket (5) is provided on the support base (6); the middle of the loading bracket (5) is used to connect the test piece; axial loading units and radial loading units are respectively provided on the outer walls of the loading bracket (5); the axial loading unit and the radial loading unit respectively provide axial force and radial force alone and transmit them to the test piece through the loading bracket (5), or provide combined bending moment and transmit it to the test piece through the loading bracket (5).

2. The disc-type multi-cylinder five-degree-of-freedom loading mechanism according to claim 1, wherein: Two axial force-bearing surfaces and radial force-bearing surfaces are provided on the outer wall of the loading bracket (5); the two groups of axial force-bearing surfaces are symmetrically distributed on both sides of the radial force-bearing surface.

3. A disc-type multi-cylinder five-degree-of-freedom loading mechanism according to claim 2, characterized in that: The axial loading unit includes two groups of axial brackets (1), which are symmetrically arranged on the two axial force-bearing surfaces; a number of servo cylinders (2) are evenly provided on the two groups of axial brackets (1), and the servo cylinders (2) on the two groups of axial brackets (1) are symmetrically arranged to respectively provide axial force and transmit it to the two axial force-bearing surfaces.

4. A disc-type multi-cylinder five-degree-of-freedom loading mechanism according to claim 3, characterized in that: The radial loading unit includes a radial bracket (3), which is arranged on the radial force-bearing surface; a number of servo cylinders (2) are evenly provided on the radial bracket (3) to provide radial force and transmit it to the radial force-bearing surface.

5. A disc-type multi-cylinder five-degree-of-freedom loading mechanism according to claim 4, characterized in that: The servo cylinder (2) includes a cylinder barrel (202) and a piston rod (203); the cylinder barrel (202) is fixed on the loading bracket (5); the piston rod (203) makes a telescopic movement in the cylinder barrel (202), and a loading assembly is provided at one end of the piston rod (203); the piston rod (203) transmits the acting force to the radial force-bearing surface or the axial force-bearing surface through the loading assembly.

6. A disc-type multi-cylinder five-degree-of-freedom loading mechanism according to claim 5, characterized in that: The loading assembly includes a ball head seat (205), a ball head seat gland (204) and a force-bearing disc (207); the end of the piston rod (203) is set as a universal ball head matching with the ball head seat (205) and is connected to the ball head seat (205) through the ball head seat gland (204); the force-bearing disc (207) is connected to the side of the ball head seat (205) opposite to the universal ball head and contacts the radial force-bearing surface or the axial force-bearing surface.

7. The disc-type multi-cylinder five-degree-of-freedom loading mechanism according to claim 6, characterized in that: A modified PTFE coating (208) is provided on the side of the force-bearing disc (207) contacting the radial force-bearing surface or the axial force-bearing surface; 15%-25% of carbon fiber and 5%-10% of graphite are added to the modified PTFE coating (208) on the basis of the PTFE coating.

8. The disk-type multi-cylinder five-degree-of-freedom loading mechanism according to claim 7, wherein: Flange interfaces are provided at both ends of the loading bracket (5) for fixedly connecting the test piece.

9. The disk-type multi-cylinder five-degree-of-freedom loading mechanism according to claim 8, wherein: A tension and compression sensor (206) is arranged between the ball head seat (205) and the force-bearing disc (207).

10. A disc-type multi-cylinder five-degree-of-freedom loading mechanism according to claim 9, characterized in that: A displacement sensor (201) is provided on the servo cylinder (2) for detecting the displacement of the piston rod (203).

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