A self-capturing low-friction composite groove of an inner-curve hydraulic motor valve plate and its parametric design method

Abstract

The present invention discloses a self-oil-catching low-friction composite groove of an inner curve hydraulic motor distribution plate and a parametric design method thereof. With the low-friction design of the distribution plate as the goal, a low-friction composite groove with a self-oil-catching function is designed on the plane of the sealing belt of the distribution plate. The structural parameterization modeling of the composite groove is performed and the structural parameters corresponding to the composite groove are reasonably selected to obtain distribution plate composite grooves with different structures and establish corresponding structural models. The lubricating oil film distribution, bearing capacity and friction coefficient corresponding to different structural models of the distribution plate composite groove are obtained through calculation and experiment, and the design parameters of the optimal distribution plate composite groove that meets the optimization target are obtained by comprehensive comparison. The present invention realizes the low-friction design of the distribution plate surface by designing self-oil-catching low-friction composite grooves with different structural parameters on the surface of the distribution plate of the inner curve hydraulic motor, reduces the wear of the distribution plate surface, and improves the mechanical efficiency and service life of the inner curve hydraulic motor.

Description

Technical Field

[0001] The invention belongs to the technical field of inner-curve hydraulic motors, and in particular relates to a self-oil-catching low-friction composite groove of an inner-curve hydraulic motor distribution plate and a parametric design method thereof. Background Art

[0002] The valve plate of the inner curve hydraulic motor is an important structure for achieving the high and low pressure oil distribution in the motor. However, the surface of the valve plate's valve pair is very easy to wear under extreme working conditions such as high pressure, which may lead to the failure of the valve plate, especially in the transition area between the sealing belt and the high and low pressure windows. At the same time, the high friction torque will cause the motor to lose power and affect the mechanical efficiency of the motor. Therefore, the low friction resistance design of the valve plate of the inner curve motor is particularly important. By designing self-oil-catching composite grooves on the surface of the valve plate to achieve the low friction resistance design of the valve plate, the motor can achieve a lower friction torque, thereby achieving the working efficiency of the motor.

[0003] There are many existing designs for lubricating surfaces of valve plates, but existing research mainly adopts the method of surface texturing, and there are few studies on how to design composite grooves on the surface of valve plates. In order to realize the low friction design of the valve plate of the inner curve motor, the present invention provides a parametric design method for self-oil-catching low-friction composite grooves of the valve plate of the inner curve hydraulic motor, thereby improving the efficiency of the inner curve hydraulic motor. Summary of the invention

[0004] The purpose of the present invention is to address the deficiencies in the prior art. The present invention proposes a self-oil-catching low-friction composite groove of an inner-curve hydraulic motor distribution plate and a parametric design method thereof. By designing the shape, parameters and arrangement of the composite groove, the composite groove capable of self-oil capture is designed based on the oil film characteristics of the distribution pair surface itself, thereby reducing the friction and wear on the distribution plate surface and improving the mechanical efficiency of the inner-curve hydraulic motor.

[0005] The object of the present invention is achieved through the following technical scheme: a self-capturing low-friction composite groove of an inner curve hydraulic motor valve plate and a parametric design method thereof, the method comprising the following steps:

[0006] S1: Taking the valve plate of the inner curve hydraulic motor as the research object, a low-friction composite groove with self-oil-catching function is designed on the plane of the inner sealing belt and the outer sealing belt of the valve plate. The composite groove mainly includes three types of structures: main branch, first branch and second branch. A main branch, a first branch and a second branch are a pair of minimum unit composite grooves of the valve plate; a group of composite grooves of the valve plate is M first branches, M second branches and a main branch uniformly distributed in the circumferential direction of the valve plate sealing belt; the composite groove of the valve plate is N groups of composite grooves uniformly distributed in the radial direction of the valve plate sealing belt, and then the composite groove is parametrically designed based on the constraint conditions of the valve plate auxiliary sealing belt;

[0007] S2: According to the structural parameters of the composite groove of the distribution plate in S1, the structural parameters corresponding to the composite groove are designed and reasonably selected based on the sizes of the inner sealing band and the outer sealing band of the distribution plate, and the composite grooves of the distribution plate with different structures are obtained and the corresponding structural models are established. According to the actual working conditions and boundary conditions of the distribution pair, the lubricating oil film distribution and the bearing capacity corresponding to the different structural models of the composite groove of the distribution plate are obtained by theoretical calculation; it is judged whether the obtained bearing capacity meets the design requirements. If it meets the requirements, the design range of the structural parameters of the composite groove is preliminarily determined;

[0008] S3: Based on the design range of the composite groove structural parameters of the distribution plate determined in S2, the composite grooves of the distribution plate with different structural parameters are further designed and processed. Since the friction pair contact form of the distribution plate is surface-to-surface contact, the end face friction and wear test is performed based on the friction conditions of the real distribution plate to obtain the friction coefficients corresponding to different structures of the composite grooves of the distribution plate;

[0009] S4: Compare the friction coefficients corresponding to different structural models of the distribution plate composite groove in S3, take the optimal lubrication effect of the distribution plate composite groove as the design goal, and obtain the optimal distribution plate composite groove that meets the design and use requirements, and obtain the design parameters of the optimal distribution plate composite groove that meets the optimization goal.

[0010] Furthermore, in step S1, the structural design parameters of the composite groove structure of the pair of minimum units are: the intersection points of the first branch and the second branch with the main branch are A and B respectively, the radius Ra of the main branch, the angle between the first branch and the line segment AB α , the angle between line segment AB and the second branch β , the angles between the center of the main branch and the lines connecting A and B , the length of the first branch L a , the length of the second branch L b , the width of the main branch B, the width of the first branch B 1 、The width of the second branch B 2 The groove depth between the main branch, the first branch and the second branch is D.

[0011] Furthermore, in step S1, the constraint conditions of the distribution auxiliary sealing belt are as follows: when the M first branches and the M second branches in a group of composite grooves of the distribution disk are evenly distributed in the circumferential direction of the distribution disk sealing belt, the branches do not cross or overlap; and there is no cross or overlap between adjacent main branches and branches of the N groups of composite grooves evenly distributed in the radial direction of the distribution disk sealing belt.

[0012] Furthermore, in step S2, in order to simplify the test cycle and further improve the calculation speed by reducing the calculation grid, a disc sample can be used to replace the friction characteristics, motion characteristics, etc. of the distribution plate sample, and an oil immersion environment test is used to ensure that the lubrication characteristics of the same composite groove structure on the disc sample are consistent with the lubrication characteristics on the distribution plate, and the lubricating oil film distribution and bearing capacity corresponding to different structural models of the composite groove of the distribution plate are equivalently calculated.

[0013] Furthermore, in step S2, CFD Fluent simulation software is used to establish flow field simulation models of different structures of the distribution plate composite groove, divide the calculation grid and set basic boundary conditions such as the oil film pressure of the distribution sub-sealing belt, the inlet and outlet pressures of the flow domain, and the rotation direction according to the operating conditions of the distribution plate. The lubricating oil film distribution and bearing capacity corresponding to different structural models of the distribution plate composite groove are obtained through simulation calculation.

[0014] Furthermore, in step S3, the friction conditions of the actual distribution plate include the contact state of the distribution plate and its mating friction pair, the residual clamping force, the rotation speed, etc., and the principle of equal linear velocity and contact pressure is adopted to be equivalent to the end face friction and wear test; the end face friction and wear test adopts standard ring specimens and disc specimens, the disc specimen is used to simulate the distribution plate, and the ring specimen is used to simulate its mating friction pair.

[0015] The beneficial results of the present invention are:

[0016] 1. By designing self-oil-catching low-friction composite grooves with different structural parameters on the surface of the distribution plate of the inner curve hydraulic motor, the low-friction design of the distribution plate surface is achieved by utilizing the structural design of the composite grooves, thereby improving the mechanical efficiency of the inner curve hydraulic motor.

[0017] 2. By designing a self-oil-catching low-friction composite groove on the surface of the distribution plate of the inner curve hydraulic motor, the lubrication characteristics of the distribution pair are improved, which can store abrasive debris and other exfoliated materials to a certain extent, reduce the wear on the surface of the distribution plate, and improve the reliability and service life of the inner curve hydraulic motor.

[0018] 3. The first branch and the second branch of the composite groove can actively drain the surface oil to the main branch during the rotation of the distribution pair, and automatically capture the leaked oil on the sealing belt of the inner curve hydraulic motor distribution plate to the main branch without adding external lubricating oil, which can increase the bearing capacity of the distribution pair and improve the surface lubrication ability of the distribution pair. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0020] Figure 1 A design flow chart of a self-oil-capturing low-friction composite groove structure provided by the present invention.

[0021] Figure 2 A schematic structural diagram of an inner curve hydraulic motor distribution plate provided by the present invention.

[0022] Figure 3 A locally enlarged parametric design diagram of a self-oil-capturing low-friction composite groove structure provided by the present invention.

[0023] Figure 4 A bearing pressure distribution diagram of a self-oil-capturing low-friction composite groove in a specific example provided by the present invention.

[0024] Figure 5 A comparison of friction coefficients of different branch widths of a self-capturing oil-low friction composite groove in a specific example provided by the present invention.

[0025] In the attached drawings, the reference numerals are: 1. Guide rail; 2. Roller; 3. Cylinder body; 4. Distribution plate; 5. Housing; 4.1. Outer sealing belt; 4.2. Inner sealing belt; 4.3. Local enlarged area; 4.3.1. Main branch; 4.3.2. First branch; 4.3.3. Second branch. DETAILED DESCRIPTION

[0026] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.

[0027] The present invention is further described below with reference to the accompanying drawings. The present invention provides a parameterized design method for a self-capturing low-friction composite groove of an inner curve hydraulic motor valve plate. Figure 1 As shown, the following steps are included:

[0028] S1: Taking the valve plate of the inner curve hydraulic motor as the research object, the present invention uses an inner curve hydraulic motor such as Figure 2As shown, the inner curve hydraulic motor includes a guide rail 1, a roller 2, a cylinder body 3, a distribution plate 4, and a housing 5; low-friction composite grooves with self-oil capture function are designed on the planes of the inner sealing belt and the outer sealing belt of the distribution plate, and the composite grooves mainly include three types of structures: main branches, first branches, and second branches. A main branch 4.3.1, a first branch 4.3.2, and a second branch 4.3.3 are a pair of minimum unit composite grooves of the distribution plate; a group of composite grooves of the distribution plate are M first branches, M second branches, and one main branch uniformly distributed in the circumferential direction of the distribution plate sealing belt; the composite grooves of the distribution plate are N groups of composite grooves uniformly distributed in the radial direction of the distribution plate sealing belt, and then the composite grooves are parameterized based on the constraint conditions of the distribution auxiliary sealing belt;

[0029] Further, in step S1, a local enlarged parameterized design diagram of a self-capturing oil low-friction composite groove structure provided by the present invention is as follows: Figure 3 As shown, Figure 3 That is Figure 2 The enlarged parametric design diagram of the local enlarged area in 4.3, the structural design parameters of the composite groove structure of the pair of minimum units are: the intersection points of the first branch and the second branch with the main branch are A and B respectively, the radius Ra of the main branch, the angle between the first branch and the line segment AB α , the angle between line segment AB and the second branch β , the angles between the center of the main branch and the lines connecting A and B , the length of the first branch L a , the length of the second branch L b , the width of the main branch B, the width of the first branch B 1 、The width of the second branch B 2 The groove depth D between the main branch, the first branch and the second branch;

[0030] Further, in step S1, the present invention uses an inner curve hydraulic motor valve plate such as Figure 2 As shown, 4.1 is the outer sealing belt, 4.2 is the inner sealing belt, and the low-friction composite groove with self-oil-catching function is located on the outer sealing belt and the inner sealing belt; the constraint conditions of the distribution auxiliary sealing belt are as follows: when the M first branches and the M second branches in a group of composite grooves of the distribution disk are evenly distributed in the circumferential direction of the distribution disk sealing belt, the branches do not cross or overlap; there is no cross or overlap between the adjacent main branches and branches of the N groups of composite grooves evenly distributed in the radial direction of the distribution disk sealing belt.

[0031] S2: According to the structural parameters of the composite groove of the distribution plate in S1, the structural parameters corresponding to the composite groove are designed and reasonably selected based on the sizes of the inner sealing band and the outer sealing band of the distribution plate, and the composite grooves of the distribution plate with different structures are obtained and the corresponding structural models are established. According to the actual working conditions and boundary conditions of the distribution pair, the lubricating oil film distribution and the bearing capacity corresponding to the different structural models of the composite groove of the distribution plate are obtained by theoretical calculation; it is judged whether the obtained bearing capacity meets the design requirements. If it meets the requirements, the design range of the structural parameters of the composite groove is preliminarily determined;

[0032] Furthermore, in step S2, in order to simplify the test cycle and further improve the calculation speed by reducing the calculation grid, a disc sample can be used to replace the friction characteristics, motion characteristics, etc. of the valve plate sample, and an oil immersion environment test is used to ensure that the lubrication characteristics of the same composite groove structure on the disc sample are consistent with the lubrication characteristics on the valve plate, which is used to equivalently calculate the lubricating oil film distribution and bearing capacity corresponding to different structural models of the valve plate composite groove;

[0033] Further, in step S2, CFD Fluent simulation software is used to establish flow field simulation models of different structures of the composite groove of the distribution plate, and the calculation grid is divided and the basic boundary conditions such as the oil film pressure of the distribution sub-sealing belt, the inlet and outlet pressures of the flow domain, and the rotation direction are set according to the use conditions of the distribution plate. The lubricating oil film distribution and bearing capacity corresponding to different structural models of the composite groove of the distribution plate are obtained through simulation calculation;

[0034] In a specific embodiment, the composite groove structure parameters of the equivalent disk are first determined as follows: the main branch radius Ra is 11 mm, the angle between the first branch and the line segment AB is α The angle between line segment AB and the second branch is 30° β The angles between the center of the main branch and the lines connecting A and B are 150°. is 2°, the length of the first branch is L a is 1200 μm, the length of the second branch is L b The width of the main branch is 1200 μm, the width of the main branch is 100 μm, and the width of the first branch is 1 The width of the second branch is 50 μm. 2 is 50 μm, the groove depth D of the main branch and the first branch and the second branch is 50 μm, N is 1, and M is 32; a self-capturing oil low friction composite groove under a specific example is obtained and a corresponding structural model is established. The CFD Fluent simulation software is used to divide the calculation grid and calculate the lubricating oil film distribution and bearing capacity of the composite groove under a specific example, such as Figure 4 shown.

[0035] S3: Based on the design range of the composite groove structural parameters of the distribution plate determined in S2, the composite grooves of the distribution plate with different structural parameters are further designed and processed. Since the friction pair contact form of the distribution plate is surface-to-surface contact, the end face friction and wear test is performed based on the friction conditions of the real distribution plate to obtain the friction coefficients corresponding to different structures of the composite grooves of the distribution plate;

[0036] Furthermore, in step S3, the friction conditions of the real valve plate include the contact state of the valve plate and its matching friction pair, the residual clamping force, the rotation speed, etc., and the end face friction and wear test is equivalent to the principle of equal linear speed and contact pressure; the end face friction and wear test uses standard ring specimens and disc specimens, the disc specimen is used to simulate the valve plate, and the ring specimen is used to simulate its matching friction pair;

[0037] In a specific embodiment, by changing the groove depth D of the first branch and the second branch, the influence of different branch groove depths on the friction coefficient of the composite groove of the distribution plate is studied, and the remaining structural parameters are consistent with the composite groove structural parameters of the equivalent disk determined in the above step S2; the width B of the first branch is designed 1 and the width of the second branch B 2 The diameters of the discs are the same, and are 50 μm, 100 μm, 150 μm and 200 μm respectively. The disc samples corresponding to different composite grooves are processed according to the structural parameters of steps S2 and S3. The actual working pressure of the distribution disc is selected as 35 MPa and the working speed is 100 r / min. The conditions of the end face friction and wear test are obtained by equivalent calculation. The end face friction and wear tests are carried out on the smooth disc sample and the disc samples corresponding to different composite grooves, and the friction coefficients of the disc samples corresponding to different composite grooves are obtained as follows: Figure 5 As shown, it can be seen that as the width of the first branch and the second branch increases, the friction coefficient gradually decreases, that is, the lubrication effect of the corresponding composite groove model is better. The main reason is that as the width of the first branch and the second branch increases, the self-oil capture area and oil storage range of the composite groove increase, thereby improving the bearing capacity and surface lubrication characteristics of the friction pair.

[0038] S4: Compare the friction coefficients corresponding to different structural models of the distribution plate composite groove in S3, take the optimal lubrication effect of the distribution plate composite groove as the design goal, and obtain the optimal distribution plate composite groove that meets the design and use requirements, and obtain the design parameters of the optimal distribution plate composite groove that meets the optimization goal.

[0039] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A parametric design method for a self-capturing low-friction composite groove of an inner curve hydraulic motor valve plate, characterized in that: The method comprises the following steps: S1: A low-friction composite groove with a self-oil-catching function is designed on the plane of the sealing belt of the inner curve hydraulic motor valve plate, the composite groove comprising a main fork and a first branch and a second branch connected to the main fork; the main fork is arranged on the sealing belt, the first branch and the second branch are arranged on both sides of the main fork, forming a pair of composite grooves of the minimum unit, and a plurality of units are repeatedly arranged and evenly distributed along the circumference of the main fork; S2: Based on the sealing strip size of the distribution plate, the structural parameters of the composite groove are obtained to establish the corresponding structural model. According to the actual working conditions and boundary conditions of the distribution pair, the lubricating oil film distribution and bearing capacity corresponding to different structural models of the composite groove are calculated, and the design range of the composite groove structural parameters that meet the requirements is selected; S3: Based on the design range of the composite groove structural parameters determined in S2, the composite groove of the distribution plate corresponding to different structural parameters is processed, and the friction coefficient corresponding to the different structural parameters of the composite groove of the distribution plate is obtained by end face friction and wear test based on the friction conditions of the real distribution plate; S4: Based on the test results of S3, the structural parameters corresponding to the composite groove of the distribution plate with the optimal lubrication effect are selected as the design results.

2. The parametric design method for a self-capturing low-friction composite groove of an inner curve hydraulic motor valve plate according to claim 1 is characterized in that: In step S1, composite grooves are provided on the inner sealing belt and the outer sealing belt of the inner curve hydraulic motor valve plate.

3. The parametric design method for a self-capturing low-friction composite groove of an inner curve hydraulic motor valve plate according to claim 1 is characterized in that: In step S1, the composite groove structure parameters are: the intersection points of the first branch and the second branch with the main branch are A and B respectively, the radius Ra of the main branch, the angle between the first branch and the line segment AB α , the angle between line segment AB and the second branch β , the angles between the center of the main branch and the lines connecting A and B , the length of the first branch L a , the length of the second branch L b , the width B of the main branch, the width B1 of the first branch, the width B2 of the second branch and the groove depth D of the main branch, the first branch and the second branch.

4. The parametric design method for a self-capturing low-friction composite groove of an inner curve hydraulic motor valve plate according to claim 1 is characterized in that: In step S1, a group of composite grooves of the distribution disc has M repeating units, including M first branches, M second branches and one main branch evenly distributed circumferentially on the distribution disc sealing belt; the composite grooves of the distribution disc are N groups of composite grooves evenly distributed radially on the distribution disc sealing belt.

5. The parametric design method for a self-capturing low-friction composite groove of an inner curve hydraulic motor valve plate according to claim 4 is characterized in that: In step S2, the constraint conditions of the distribution auxiliary sealing belt are: when the M first branches and the M second branches in a group of composite grooves of the distribution disk are evenly distributed in the circumferential direction of the distribution disk sealing belt, the branches do not cross or overlap; and there is no cross or overlap between the adjacent main branches and branches of the N groups of composite grooves evenly distributed in the radial direction of the distribution disk sealing belt.

6. The parametric design method for a self-capturing low-friction composite groove of an inner curve hydraulic motor valve plate according to claim 1 is characterized in that: In step S2, in order to simplify the test cycle and further improve the calculation speed by reducing the calculation grid, a disc sample is used to replace the friction characteristics and motion characteristics of the distribution plate sample. At the same time, an oil immersion environment test is used to ensure that the lubrication characteristics of the same composite groove structure on the disc sample are consistent with the lubrication characteristics on the distribution plate. The lubricating oil film distribution and bearing capacity corresponding to different structural models of the composite groove of the distribution plate are equivalently calculated.

7. The parametric design method for a self-capturing low-friction composite groove of an inner curve hydraulic motor valve plate according to claim 1 is characterized in that: In step S2, CFD Fluent simulation software is used to establish flow field simulation models of different structures of the distribution plate composite groove, divide the calculation grid, and set the oil film pressure of the distribution sub sealing belt, the inlet and outlet pressures of the flow domain, and the rotation direction boundary conditions according to the operating conditions of the distribution plate. After simulation calculation, the lubricating oil film distribution and bearing capacity corresponding to different structural models of the distribution plate composite groove are obtained.

8. The parametric design method for a self-capturing low-friction composite groove of an inner curve hydraulic motor valve plate according to claim 1 is characterized in that: In step S3, the friction conditions of the actual distribution disc include the contact state of the distribution disc and its mating friction pair, the residual clamping force and the rotation speed, and the end face friction and wear test is equivalent to the principle of equal linear speed and contact pressure; the end face friction and wear test uses standard ring specimens and disc specimens, the disc specimen is used to simulate the distribution disc, and the ring specimen is used to simulate its mating friction pair.

9. The parametric design method for a self-capturing low-friction composite groove of an inner curve hydraulic motor valve plate according to claim 1, characterized in that: The first branch and the second branch of the composite groove guide the surface oil to the main branch during the rotation of the distribution pair. Without adding external lubricating oil, the leaked oil on the sealing belt of the inner curve hydraulic motor distribution plate is automatically captured to the main branch, thereby increasing the bearing capacity of the distribution pair and improving the surface lubrication ability of the distribution pair.

10. A self-capturing low-friction composite groove of an inner curve hydraulic motor valve plate based on the parametric design method of the self-capturing low-friction composite groove according to any one of claims 1 to 9, characterized in that: The composite groove includes a main branch and a first branch and a second branch connected to the main branch; the main branch is arranged on the sealing belt, and the first branch and the second branch are arranged on both sides of the main branch to form a pair of minimum unit composite grooves, and multiple units are repeatedly arranged and evenly distributed along the circumference of the main branch to form a group of composite grooves; when the branches are evenly distributed in the circumferential direction of the distribution disk sealing belt, there is no cross-overlap; there is no cross-overlap between adjacent main branches and branches of multiple groups of composite grooves evenly distributed in the radial direction of the distribution disk sealing belt.

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