An in-situ testing device and method for friction characteristics of the flow distribution interface of an inner-curve radial piston hydraulic motor

Abstract

The present invention discloses an in-situ testing device and method for the interface friction characteristics of the distribution pair of an inner curve radial piston hydraulic motor. The transmission shaft of the distribution pair simulation module is connected to the motor, and the distribution pair simulation module is threadedly connected to the distribution pair guide module. By controlling the motor speed and the high and low pressure distribution window pressures of the distribution plate, the high and low pressure distribution function of the distribution pair in the hydraulic motor and the wear state of the interface between the simulated distribution plate and the cylinder body can be truly restored, so that the interface friction characteristics of the distribution pair are consistent with the in-situ measurement results. Compared with the whole machine test of the hydraulic motor, the in-situ testing device for the interface friction characteristics of the distribution pair proposed by the present invention is easy to assemble and disassemble, has high reliability, and has a low test cycle and test cost. At the same time, it has universality and applicability for the comprehensive performance test of the distribution plate of the inner curve radial piston hydraulic motor.

Description

Technical Field

[0001] The invention belongs to the technical field of inner-curve radial piston hydraulic motors, and in particular relates to an in-situ testing device and method for friction characteristics of a distribution pair interface of an inner-curve radial piston hydraulic motor. Background Art

[0002] At present, ultra-large torque low-speed hydraulic drive systems are used in various national heavy equipment, such as the screw conveying system of large shield machines, the reamer drive system of dredgers and other large rotary drive systems. Among them, the inner curve radial piston hydraulic motor has the advantages of high power density, light weight and compactness compared with high-speed hydraulic motors / motors and reducers.

[0003] However, the numerous friction pair interfaces in the compact space of the inner curve radial piston hydraulic motor have strong nonlinear and fluctuating characteristics of friction, which restricts the mechanical efficiency and volumetric efficiency of the inner curve radial piston hydraulic motor. Among them, the distribution pair is one of the key friction pairs of the inner curve radial piston hydraulic motor, and its structural and functional characteristics have a key impact on the efficiency of the motor. Existing research on the friction characteristics of the distribution pair of the inner curve radial piston hydraulic motor is mainly completed through the motor whole machine test. Due to the large number of friction pair interfaces inside the inner curve radial piston hydraulic motor, it is difficult to qualitatively distinguish and quantitatively separate which friction pair causes the overall friction of the motor and even the temperature rise, and it is impossible to conduct a comprehensive study on the characteristics of a single friction pair. Furthermore, since the roller piston and other components in the motor are more easily damaged during the whole machine test, the moving components need to be constantly replaced, resulting in high test costs and long test cycles, which limits the design optimization and performance improvement of the distribution pair of the inner curve radial piston hydraulic motor.

[0004] Therefore, in order to be able to study the friction and wear characteristics of the distribution pair and improve the efficiency of the inner curve radial piston hydraulic motor at the same time, the present invention proposes an in-situ testing device and method for the interface friction characteristics of the distribution pair of the inner curve radial piston hydraulic motor, which helps to improve the performance of the inner curve radial piston hydraulic motor to meet the requirements of different application fields. Summary of the invention

[0005] The purpose of the present invention is to address the deficiencies of the prior art and to provide an in-situ testing device and method for the friction characteristics of the flow distribution interface of an inner-curve radial piston hydraulic motor.

[0006] The object of the present invention is achieved through the following technical scheme: an in-situ testing device for the friction characteristics of the flow distribution interface of an inner curve radial piston hydraulic motor, the device comprising a motor, a flow distribution simulation module and a flow distribution guide module;

[0007] The distribution pair simulation module includes a transmission shaft, a cylinder body, a loading chamber, a distribution plate, a high-pressure distribution window and a low-pressure distribution window of the distribution plate; the cylinder body in the distribution pair simulation module is connected to the motor through a transmission shaft; the high-pressure distribution window and the low-pressure distribution window of the distribution plate are staggered; the loading chamber is used to control the input oil so that the loading force of the cavity oil is equal to the pressing force of the distribution plate, so as to realize the calibration of the equivalent in-situ test friction torque;

[0008] The flow distribution sub-guiding module includes an oil inlet loop and an oil return loop; the oil inlet loop of the flow distribution sub-guiding module is connected to the high-pressure flow distribution window of the flow distribution plate; the oil return loop of the flow distribution sub-guiding module is connected to the low-pressure flow distribution window of the flow distribution plate;

[0009] A torque sensor is installed on the transmission shaft; the torque sensor obtains the friction torque of the distribution pair interface through data collection and calibration calculation.

[0010] Furthermore, the flow distribution sub-simulated module has a flow distribution sub-simulated module self-aligning ball bearing, which is used to ensure that the flow distribution sub-simulated module, the flow distribution sub-flow guide module and the transmission shaft are always concentric.

[0011] Furthermore, the flow distribution sub-simulated module has a flow distribution sub-simulated module thrust cylindrical roller bearing for bearing the axial force exerted on the cylinder body.

[0012] Furthermore, the flow distribution pair simulation module has a flow distribution state observation window for observing the flow field flow state of the flow distribution pair.

[0013] Furthermore, when the cylinder window of the cylinder body in the distribution sub-simulation module is connected with the high-pressure distribution window of the distribution plate, the high-pressure oil enters the oil passage through the oil inlet loop of the distribution sub-guiding module, and then enters the high-pressure distribution window of the distribution plate to enter the distribution sub-interface, and the oil is input into the cylinder window of the cylinder body of the distribution sub-simulation module and enters the plunger cavity of the cylinder body, completing the inflow function of the high-pressure oil of the distribution plate.

[0014] Furthermore, when the cylinder window of the cylinder body in the distribution sub-simulation module is connected with the low-pressure distribution window of the distribution plate, the oil in the plunger chamber of the cylinder body becomes low-pressure oil and flows from the cylinder window of the cylinder body of the distribution sub-simulation module into the low-pressure distribution window of the distribution plate, and then enters the oil passage port of the distribution sub-guiding module and returns to the oil tank through the oil return loop, completing the low-pressure oil outflow function of the distribution plate.

[0015] Furthermore, the loading chamber of the distribution plate simulation module is used to control the oil input pressure so that the loading pressure of the chamber generates a loading force on the transmission shaft, and the loading force is equal to the pressing force of the distribution plate.

[0016] Furthermore, the friction torque of the drive shaft and the transmission system connected to it when the distribution plate is not working is obtained through torque sensor testing, and the friction torque measured by the torque sensor when the distribution plate is working is calibrated to eliminate the influence of the friction torque of the drive shaft and the transmission system connected to it on the friction torque of the distribution pair, thereby realizing the calibration of the equivalent in-situ test friction torque.

[0017] Furthermore, the oil inlet of the inner cavity of the distribution pair simulation module inputs oil into and fills the distribution pair simulation module to simulate the in-situ working environment of the distribution pair in the hydraulic motor.

[0018] On the other hand, the present invention also provides an in-situ testing method for the friction characteristics of the flow distribution interface of an inner curve radial piston hydraulic motor, the method comprising the following steps:

[0019] (1) According to the assembly sequence of the flow distribution sub-simulation module, install the tested distribution plate and the corresponding cylinder body at the corresponding positions of the flow distribution sub-simulation module, and adjust the initial matching clearance between the distribution plate and the cylinder body;

[0020] (2) After the assembly of the flow distribution sub-simulation module is completed, its transmission shaft is connected to the torque sensor through a coupling. After it is fully installed, the flow distribution sub-simulation module is fixedly connected to the test bench frame by bolts;

[0021] (3) Connect the oil inlet of the distribution pair virtual module cavity, the high-pressure oil inlet of the distribution pair, the oil return port of the distribution pair virtual module cavity, the oil port of the distribution pair loading circuit and the low-pressure oil return port of the distribution pair to the corresponding oil ports of the hydraulic system respectively, and install the pressure and temperature sensor of the distribution pair leakage port, the pressure and temperature sensor of the distribution pair high-pressure port, the pressure and temperature sensor of the distribution pair loading circuit and the pressure and temperature sensor of the distribution pair low-pressure port at the corresponding positions;

[0022] (4) After the installation is completed, start the hydraulic system, fill the inner cavity of the distribution sub-simulation module with oil through the inner cavity oil inlet of the distribution sub-simulation module, and after the inner cavity of the distribution sub-simulation module is filled with oil, close the inner cavity oil inlet of the distribution sub-simulation module and open the inner cavity oil return port of the distribution sub-simulation module, and adjust the working pressure and oil temperature of the distribution plate;

[0023] (5) Then start the motor and adjust the motor speed to change the working speed of the control cylinder;

[0024] (6) Through the test process of the above steps (1) to (5), by adjusting the working pressure and the working speed, the friction characteristics of the distribution pair of the current distribution plate under different working conditions are tested;

[0025] (7) After the above working condition test is completed, the hydraulic system is switched, the high-pressure oil inlet of the distribution pair is closed, so that the current distribution plate is in a non-distribution working state, and the oil port of the distribution pair loading circuit is opened. The oil pressure of the loading circuit is adjusted according to the clamping force of the distribution plate to keep it consistent with the residual clamping force of the distribution plate. The friction torque of the transmission shaft and its transmission system is obtained by testing, and the friction torque of the distribution pair can be obtained by subtracting it from the friction torque obtained in the test in step (6);

[0026] (8) After the above tests are completed, remove the distribution plate under test and observe the wear condition of the distribution pair after the test under a microscope.

[0027] The beneficial results of the present invention are:

[0028] 1. The present invention proposes an in-situ testing device and method for the interface friction characteristics of the distribution pair of an inner curve radial piston hydraulic motor. Through the design of the distribution pair guide module and the distribution pair simulation module, it can truly restore the high and low pressure distribution function of the distribution pair in the hydraulic motor and simulate the wear state of the interface between the distribution plate and the cylinder body, so that the interface friction characteristics of the distribution pair are consistent with the in-situ measurement results.

[0029] 2. Compared with the internal curve radial piston hydraulic motor, the internal curve radial piston hydraulic motor distribution pair test device proposed by the present invention has fewer parts and higher reliability. Especially when studying the friction characteristics of different distribution pair interfaces under durable working conditions, the test device of the present invention only needs to replace different distribution plates. However, when using the hydraulic motor for testing, not only do different distribution plates need to be replaced, but the rollers, plungers and other parts inside are more easily worn and need to be frequently replaced, resulting in high testing costs and long assembly cycles.

[0030] 3. The internal curve radial piston hydraulic motor distribution pair testing device proposed in the present invention can realize comprehensive performance testing of various forms of distribution pairs by replacing the distribution pair simulation test module, because the distribution pair simulation module is replaceable and easy to install and disassemble. It is universal and applicable to the comprehensive performance testing of the distribution plate of the internal curve radial piston hydraulic motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] 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.

[0032] Figure 1 An axonometric diagram of an in-situ testing device for the friction characteristics of the distribution pair interface of an inner-curve radial piston hydraulic motor provided by the present invention.

[0033] Figure 2 The left side view of an in-situ testing device for the friction characteristics of the flow distribution interface of an inner-curve radial piston hydraulic motor provided by the present invention.

[0034] Figure 3 A schematic cross-sectional view (AA) of a distribution pair simulation module, a distribution pair flow guide module and a sealing end cover of an in-situ testing device for the interface friction characteristics of a distribution pair of an inner-curve radial piston hydraulic motor provided by the present invention.

[0035] Figure 4 A schematic cross-sectional (BB) diagram of a distribution pair simulation module, a distribution pair flow guide module and a sealing end cover of an in-situ testing device for the interface friction characteristics of a distribution pair of an inner-curve radial piston hydraulic motor provided by the present invention.

[0036] Figure 5 A schematic diagram of a distribution plate in a distribution pair simulation module of an in-situ testing device for the interface friction characteristics of a distribution pair of an inner-curve radial piston hydraulic motor provided by the present invention.

[0037] Figure 6 A cylinder body and a cross-sectional view thereof in a distribution pair simulation module of an in-situ testing device for the interface friction characteristics of a distribution pair of an inner-curve radial piston hydraulic motor provided by the present invention.

[0038] Figure 7 A schematic diagram of a distribution pair flow guide module of an in-situ testing device for the friction characteristics of the distribution pair interface of an inner-curve radial piston hydraulic motor provided by the present invention.

[0039] Figure 8 A schematic diagram of the wear condition of a distribution plate 6.1a of an in-situ testing device for the friction characteristics of the distribution pair interface of an inner-curve radial piston hydraulic motor provided by the present invention after being tested by the testing device described in the present invention.

[0040] Fig. 9 This is a schematic diagram of the wear condition of an inner curve radial piston hydraulic motor distribution plate 6.1b provided by the present invention after being installed on a hydraulic motor and undergoing a whole machine test on a comprehensive performance test bench.

[0041] In the attached drawings, the reference numerals are: 1-motor; 2-reducer; 3-reducer bracket; 4-coupling; 5-torque sensor; 6-distribution pair virtual module; 7-distribution state observation window; 8-distribution pair flow guide module; 9-sealed end cover; 10-distribution pair leakage port pressure and temperature sensor; 11-distribution pair high pressure port pressure and temperature sensor; 12-distribution pair loading circuit pressure and temperature sensor; 13-test bench stand; 14-eddy current displacement sensor; 15-distribution pair virtual module inner cavity oil inlet; 16-distribution pair flow guide module and sealing end cover connecting bolt 1; 17-distribution pair high pressure oil inlet; 18-distribution pair flow guide module and sealing end cover connecting bolt 2; 19-distribution pair virtual module inner cavity oil return port; 20-distribution pair loading circuit oil port; 21 - low-pressure oil return port of the distribution pair; 22- connection bolts between the distribution pair flow guide module and the distribution pair virtual module; 23- pressure and temperature sensor of the distribution pair low-pressure port; 6.1- distribution plate of the distribution pair virtual module; 6.2- self-aligning ball bearing 2 of the distribution pair virtual module; 6.3- cylinder body of the distribution pair virtual module; 6.4- left end cover of the distribution pair virtual module; 6.5- lower end cover of the distribution pair virtual module; 6.6- thrust cylindrical roller bearing of the distribution pair virtual module; 6.7- self-aligning ball bearing 1 of the distribution pair virtual module; 6.8- transmission shaft of the distribution pair virtual module; 6.9- support end cover of the distribution pair virtual module; 6.10- right end cover of the distribution pair virtual module; 6.11- upper end cover of the distribution pair virtual module; 6.12- observation window of the distribution pair virtual module and the distribution state Connecting bolts; 6.13-loading cavity of the distribution pair virtual module; 6.14-connecting bolts of the distribution pair virtual module cylinder body and the transmission shaft; 6.1.1-limiting bolt mounting hole of the distribution plate; 6.1.2-high-pressure distribution window of the distribution plate; 6.1.3-low-pressure distribution window of the distribution plate; 6.1.4-eddy current sensor mounting hole of the distribution plate; 6.1.5-transition window of the distribution plate; 6.1.6-spring sleeve of the distribution plate; 6.1.7-spring of the distribution plate; 6.1.8-balancing plunger of the distribution plate; 6.3.1-sealing window cover of the cylinder body; 6.3.2-cylinder window of the cylinder body; 6.3.3-locating pin of the cylinder body; 6.3.4-plunger cavity of the cylinder body; 6.3.5-first connecting surface of the cylinder body; 6.3.6 -The second connecting surface of the cylinder body; 8.1-the connecting threaded hole between the distribution sub-guiding module and the distribution sub-simulated module; 8.2-the oil passage of the distribution sub-guiding module; 8.3-the lead hole of the eddy current sensor of the distribution sub-guiding module; 8.4-the connecting threaded hole between the distribution sub-guiding module and the distribution plate; 8.5-the oil inlet loop of the distribution sub-guiding module; 8.6-the first sealing ring of the distribution sub-guiding module; 8.7-the second sealing ring of the distribution sub-guiding module; 8.8-the third sealing ring of the distribution sub-guiding module; 8.9-the sealing grid ring mounting surface of the distribution sub-guiding module; 8.10-the self-aligning ball bearing mounting surface of the distribution sub-guiding module; 8.11-the oil return loop of the distribution sub-guiding module; 8.12-the fourth sealing ring of the distribution sub-guiding module. DETAILED DESCRIPTION

[0042] 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.

[0043] The present invention is further described below with reference to the accompanying drawings. The present invention provides an in-situ testing device for the friction characteristics of the flow distribution interface of an inner curve radial piston hydraulic motor. Figure 1 and Figure 2 As shown, it includes a motor 1, a reducer 2, a reducer bracket 3, a coupling 4, a torque sensor 5, a distribution pair simulated module 6, a distribution state observation window 7, a distribution pair guide module 8, a sealing end cover 9, a distribution pair leakage port pressure and temperature sensor 10, a distribution pair high-pressure port pressure and temperature sensor 11, a distribution pair loading circuit pressure and temperature sensor 12, a test bench stand 13, an eddy current displacement sensor 14, a distribution pair simulated module inner cavity oil inlet 15, a distribution pair guide module and a sealing end cover connecting bolt 16, a distribution pair high-pressure oil inlet 17, a distribution pair guide module and a sealing end cover connecting bolt 2 18, a distribution pair simulated module inner cavity oil return port 19, a distribution pair loading circuit oil port 20, a distribution pair low-pressure oil return port 21, a distribution pair guide module and a distribution pair simulated module connecting bolt 22, and a distribution pair low-pressure port pressure and temperature sensor 23;

[0044] like Figure 3 and Figure 4 As shown, the present invention provides a flow distribution pair simulated module, a flow distribution pair flow guide module and a sealing end cover of an in-situ test device for the friction characteristics of the flow distribution pair interface of an inner curve radial piston hydraulic motor, wherein the flow distribution pair simulated module includes a flow distribution pair simulated module flow distribution plate 6.1, a flow distribution pair simulated module self-aligning ball bearing 2 6.2, a flow distribution pair simulated module cylinder body 6.3, a flow distribution pair simulated module left end cover 6.4, a flow distribution pair simulated module lower end cover 6.5, a flow distribution pair simulated module 6.6, thrust cylindrical roller bearing of the distribution vice simulation module, self-aligning ball bearing 6.7, transmission shaft of the distribution vice simulation module 6.8, support end cover 6.9 of the distribution vice simulation module, right end cover 6.10 of the distribution vice simulation module, upper end cover 6.11 of the distribution vice simulation module, bolts connecting the distribution vice simulation module and the distribution state observation window 6.12, loading chamber 6.13 of the distribution vice simulation module, bolts connecting the cylinder body of the distribution vice simulation module and the transmission shaft 6.14;

[0045] like Figure 1-Figure 4As shown, the distribution pair simulated module 6 is fixed on the test bench stand 13, the distribution pair simulated module 6 is connected to the distribution pair guide module 8 through the threaded connection threaded hole 8.1, the cylinder body 6.3 and the transmission shaft 6.8 in the distribution pair simulated module are connected by bolts 6.14 and interference fit, the transmission shaft 13 is connected to the torque sensor 5 through the coupling 4, and the other side of the torque sensor 5 is connected to the reducer 2 through the coupling 4, wherein the reducer 2 is fixed on the reducer bracket 3, and the other side is connected to the motor 1, and the side connection relies on the motor 1 to drive the cylinder body 6.3 in the distribution pair simulated module to rotate through a coaxial connection, and the speed of the cylinder body 6.3 is indirectly controlled by controlling the speed of the motor 1, and the torque sensor 5 obtains the friction torque of the distribution plate 6.1 and the cylinder body 6.3 distribution pair in the distribution pair simulated module through data acquisition and shaft system verification calculation;

[0046] like Figure 5 As shown, the present invention provides a distribution plate of an in-situ testing device for the friction characteristics of the distribution pair interface of an inner curve radial piston hydraulic motor, comprising a limit bolt mounting hole 6.1.1 of the distribution plate, a high-pressure distribution window 6.1.2 of the distribution plate, a low-pressure distribution window 6.1.3 of the distribution plate, an eddy current sensor mounting hole 6.1.4 of the distribution plate, a transition window 6.1.5 of the distribution plate, a spring sleeve 6.1.6 of the distribution plate, a spring 6.1.7 of the distribution plate, and a balancing plunger 6.1.8 of the distribution plate; the distribution pair guide module 8 and the distribution plate 6.1 of the distribution pair simulation module are connected by bolts in the limit bolt mounting hole 6.1.1 and the connecting threaded hole 8.4 of the distribution pair guide module and the distribution plate, and the high The high-pressure distribution window 6.1.2, the transition window 6.1.5 of the distribution plate and the low-pressure distribution window 6.1.3 of the distribution plate are arranged alternately in sequence. The spring sleeve 6.1.6 on the inlet and outlet sides of the distribution plate 6.1 in the distribution pair simulation module is concentric with the distribution window. The spring 6.1.7 is placed in the spring sleeve 6.1.6. The spring sleeve 6.1.6 is completely and tightly fitted with the inlet side of the distribution plate by the oil pressure and the spring pressure. The eddy current displacement sensor 14 is installed through the eddy current sensor lead hole 8.3 of the distribution pair guide module and the eddy current sensor installation hole 6.1.4 of the distribution plate, and the sensor test end face is parallel to the distribution surface, and has a certain initial gap with the cylinder body matching surface, which is used to test the oil film thickness of the distribution pair.

[0047] like Figure 6As shown, the present invention provides a cylinder body of an in-situ testing device for the friction characteristics of the distribution pair interface of an inner curve radial piston hydraulic motor, comprising a sealing window cover 6.3.1 of the cylinder body, a cylinder window 6.3.2 of the cylinder body, a positioning pin 6.3.3 of the cylinder body, a plunger cavity 6.3.4 of the cylinder body, a first connecting surface 6.3.5 of the cylinder body, and a second connecting surface 6.3.6 of the cylinder body; the cylinder body 6.3 and the transmission shaft 6.8 are connected and limited by the positioning pin 6.3.3 of the cylinder body, the first connecting surface 6.3.5 of the cylinder body and the second connecting surface 6.3.6 of the cylinder body are interference fit with the transmission shaft 6.8, and the sealing window cover 6.3.1 of the cylinder body is connected to the plunger cavity 6.3.4 of the cylinder body by bolts;

[0048] like Figure 7 As shown, the present invention provides a flow distribution pair guide module of an in-situ test device for the friction characteristics of the flow distribution pair interface of an inner curve radial piston hydraulic motor, comprising a connecting threaded hole 8.1 of the flow distribution pair guide module and the flow distribution pair virtual module, an oil passage 8.2 of the flow distribution pair guide module, an eddy current sensor lead hole 8.3 of the flow distribution pair guide module, a connecting threaded hole 8.4 of the flow distribution pair guide module and the flow distribution plate, an oil inlet loop 8.5 of the flow distribution pair guide module, and a first sealing hole 8.6 of the flow distribution pair guide module. Sealing ring 8.6, second sealing ring 8.7 of distribution sub-flow guide module, third sealing ring 8.8 of distribution sub-flow guide module, sealing Gley ring mounting ring surface 8.9 of distribution sub-flow guide module, self-aligning ball bearing mounting surface 8.10 of distribution sub-flow guide module, oil return loop 8.11 of distribution sub-flow guide module, fourth sealing ring 8.12 of distribution sub-flow guide module; spring between the oil passage 8.2 of distribution sub-flow guide module and the inlet and outlet sides of distribution plate 6.1 in distribution sub-real module The sliding sleeve 6.1.6 is concentric and has clearance fit, the oil inlet loop 8.5 of the distribution sub-guiding module is connected with the distribution sub-high pressure oil inlet port 17 to flow the high pressure oil into the distribution plate 6.1, and the oil return loop 8.11 of the distribution sub-guiding module is connected with the distribution sub-low pressure oil return port 21 to flow the low pressure oil out of the distribution plate 6.1; the first sealing ring 8.6 of the distribution sub-guiding module, the second sealing ring 8.7 of the distribution sub-guiding module, the third sealing ring 8.8 of the distribution sub-guiding module, and the distribution sub-guiding module are connected to the distribution sub-high pressure oil inlet port 17 to flow the high pressure oil into the distribution plate 6.1. The fourth sealing ring 8.12 of the flow sub-guiding module is installed with sealing rings to isolate the oil in different cavities to avoid oil cross-talk. The sealing grid ring installation ring surface 8.9 of the flow sub-guiding module is installed with grid rings to prevent leakage of high-pressure oil in the loading cavity 6.13 of the flow sub-simulated module. The self-aligning ball bearing installation surface 8.10 of the flow sub-guiding module is installed with the second self-aligning ball bearing 6.2 of the flow sub-simulated module to ensure that the flow sub-guiding module 6 and the transmission shaft 6.8 are always concentric.

[0049] like Figure 3-Figure 7As shown, when the cylinder window 6.3.2 of the distribution sub-simulation module is connected with the high-pressure distribution window 6.1.2 of the distribution plate, the high-pressure oil enters the oil passage 8.2 through the oil inlet loop 8.5 of the distribution sub-guiding module and then enters the high-pressure distribution window 6.1.2 of the distribution plate to enter the distribution sub-interface, and the oil is input into the cylinder window 6.3.2 of the cylinder 6.3 of the distribution sub-simulation module and enters the plunger cavity 6.3.4 of the cylinder, completing the inflow function of the high-pressure oil of the distribution plate 6.1;

[0050] like Figure 3-Figure 7 As shown, when the cylinder window 6.3.2 of the distribution sub-simulation module is connected with the low-pressure distribution window 6.1.3 of the distribution plate, the oil in the plunger cavity 6.3.4 of the cylinder body becomes low-pressure oil and flows from the cylinder window 6.3.2 of the distribution sub-simulation module cylinder body 6.3 into the low-pressure distribution window 6.1.3 of the distribution plate, and then enters the oil passage 8.2 of the distribution sub-guiding module and returns to the oil tank through the oil return loop 8.11, completing the outflow function of the low-pressure oil of the distribution plate 6.1;

[0051] like Figure 1-Figure 4 As shown, the oil port 20 of the distribution pair loading circuit is connected to the distribution pair virtual module loading cavity 6.13 to control the oil input pressure so that the loading pressure of this cavity is equal to the clamping force of the distribution plate, which is used to check the friction torque of the mechanical structure transmission system under non-distribution working conditions and compare it with the friction torque of the whole system when the distribution plate is working, so as to accurately obtain the friction torque of the distribution pair;

[0052] like Figure 1-Figure 4 As shown, the flow distribution state observation window 7 is made of transparent material, which can directly observe the flow field flow state of the flow distribution pair. The distribution plate 6.1 and the cylinder body 6.3 can be further changed to transparent materials such as acrylic plates, and the PIV observation equipment can be used to test the flow field state of the oil flow field streamline distribution, vortex, etc. of the distribution plate under low pressure conditions;

[0053] like Figure 1 and Figure 2 As shown, the distribution sub leakage port pressure and temperature sensor 10, the distribution sub high pressure port pressure and temperature sensor 11 and the distribution sub low pressure port pressure and temperature sensor 23 can respectively test and obtain the oil pressure and oil temperature of the distribution sub high pressure port, low pressure port and leakage port;

[0054] like Figure 2As shown, the oil inlet 15 of the distribution pair simulated module inner cavity inputs oil with a certain pressure and fills the distribution pair simulated module 6 to simulate the oil-immersed working state of the distribution pair in the hydraulic motor. After the distribution pair simulated module inner cavity is filled with oil, the oil inlet 15 of the distribution pair simulated module inner cavity is closed and the oil return port 19 of the distribution pair simulated module inner cavity is opened. Due to the existence of system back pressure, the oil in the distribution pair simulated module inner cavity will not flow out. When the distribution plate starts to work, the leaked oil generated by the distribution pair will flow into the distribution pair simulated module inner cavity. At this time, the total amount of oil in the closed cavity increases, and due to the incompressibility of the oil, the oil pressure in the cavity increases. At this time, the excess oil will flow out from the oil return port 19 of the distribution pair simulated module inner cavity until the total amount of oil returns to the volume when the cavity is just filled. At this time, the oil in the distribution pair simulated module inner cavity will no longer continue to flow out.

[0055] like Figure 3 and Figure 4 As shown, the eddy current displacement sensor 14 can be used to check the initial matching clearance between the distribution plate 6.1 and the cylinder body 6.3 to ensure that the installation state is consistent with the installation position in the hydraulic motor, so that the oil pressure and oil temperature at the high-pressure port, the low-pressure port, and the leakage port can ensure that the force state of the distribution pair is consistent with the force state of the distribution pair of the hydraulic motor, thereby obtaining the friction and wear state of the distribution plate.

[0056] Corresponding to the above-mentioned embodiment of an in-situ testing device for the friction characteristics of the distribution pair interface of an inner curve radial piston hydraulic motor, the present invention also provides a testing method for the in-situ testing device for the friction characteristics of the distribution pair interface of an inner curve radial piston hydraulic motor, and the specific steps are as follows:

[0057] (1) Prepare two identical valve plate 6.1a, 6.1b and two identical cylinder bodies 6.3a, 6.3b. According to the assembly sequence of the valve plate sub-simulation module 6, install the valve plate 6.1a to be tested and the corresponding cylinder body 6.3a in the corresponding positions of the valve plate sub-simulation module 6, and adjust the initial matching clearance between the valve plate 6.1 and the cylinder body 6.3;

[0058] (2) After the assembly of the distribution sub-simulation module 6 is completed, its transmission shaft 6.8 is connected to the torque sensor 5 through the coupling 4. After it is fully installed, the distribution sub-simulation module 6 is fixedly connected to the test bench frame 13 by bolts;

[0059] (3) The inner cavity oil inlet 15 of the distribution pair virtual module, the high pressure oil inlet 17 of the distribution pair, the inner cavity oil return port 19 of the distribution pair virtual module, the oil port 20 of the distribution pair loading circuit and the low pressure oil return port 21 of the distribution pair are respectively connected to the corresponding oil ports of the hydraulic system, and the sensors of the distribution pair leakage port pressure temperature sensor 10, the distribution pair high pressure port pressure temperature sensor 11, the distribution pair loading circuit pressure temperature sensor 12 and the distribution pair low pressure port pressure temperature sensor 23 are installed at the corresponding positions;

[0060] (4) After the installation is completed, the hydraulic system is turned on, and the inner cavity of the distribution sub-simulated module is filled with oil through the inner cavity oil inlet 15 of the distribution sub-simulated module. After the inner cavity of the distribution sub-simulated module is filled with oil, the inner cavity oil inlet 15 of the distribution sub-simulated module is closed and the inner cavity oil return port 19 of the distribution sub-simulated module is opened, and the working pressure and oil temperature of the distribution plate 6.1 are adjusted;

[0061] (5) Then start the motor 1, and adjust the speed of the motor 1 to change the working speed of the control cylinder 6.3;

[0062] (6) Through the test process of the above steps (1) to (5), by adjusting the working pressure and working speed, the basic characteristics of the current valve plate such as friction and temperature under different working conditions can be tested, and the test can be carried out continuously for 15 hours;

[0063] (7) After the above working condition test is completed, the hydraulic system is switched, the high-pressure oil inlet port 17 of the distribution pair is closed, so that the current distribution plate is in a non-distribution working state, and the distribution pair loading circuit oil port 20 is opened. The oil pressure of the loading circuit is adjusted according to the clamping force of the distribution plate to keep it consistent with the residual clamping force of the distribution plate. The friction torque of the shaft system is obtained by testing, and the friction torque of the distribution pair can be obtained by subtracting it from the friction torque obtained in the test in step (6);

[0064] (8) After all the above tests are completed, remove the tested distribution plate 6.1a and observe the wear state of the distribution pair after the test under a microscope. Figure 8 As shown;

[0065] (9) At the same time, the tested valve plate 6.1b and the corresponding cylinder body 6.3b are installed in the inner curve radial piston hydraulic motor, and the working conditions and test cycles are set to be exactly the same as those in the above test process steps (4) to (6). After all the above tests are completed, the tested valve plate 6.1b is removed and the wear state of the valve pair after the test is observed under a microscope. Fig. 9 By comparison, the wear areas of the tested valve plates 6.1a and 6.1b are basically the same, and the wear characteristics such as pear grooves appear at the junction of the high and low pressure windows, which further verifies that the test device and method proposed in the present invention can realize the in-situ test of the friction characteristics of the valve pair interface of the inner curve radial piston hydraulic motor.

[0066] 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. An in-situ testing device for the friction characteristics of the flow distribution interface of an inner curve radial piston hydraulic motor, characterized in that: The device comprises a motor, a flow distribution sub-simulation module and a flow distribution sub-flow diversion module; The distribution pair simulation module includes a transmission shaft, a cylinder body, a loading chamber, a distribution plate, a high-pressure distribution window and a low-pressure distribution window of the distribution plate; the cylinder body in the distribution pair simulation module is connected to the motor through a transmission shaft; the high-pressure distribution window and the low-pressure distribution window of the distribution plate are staggered; the loading chamber is used to control the input oil so that the loading force of the cavity oil is equal to the clamping force of the distribution plate, so as to realize the calibration of the equivalent in-situ test friction torque; the oil inlet of the inner cavity of the distribution pair simulation module inputs the oil and fills the distribution pair simulation module to simulate the in-situ working environment of the distribution pair in the hydraulic motor; the distribution pair guide module includes an oil inlet loop and an oil return loop; the oil inlet loop of the distribution pair guide module is connected to the high-pressure distribution window of the distribution plate; the oil return loop of the distribution pair guide module It is connected with the low-pressure distribution window of the distribution plate; when the cylinder window of the cylinder body in the distribution sub-simulation module is connected with the high-pressure distribution window of the distribution plate, the high-pressure oil enters the oil passage through the oil inlet loop of the distribution sub-guiding module, and then enters the high-pressure distribution window of the distribution plate to enter the distribution sub-interface, and the oil is input to the cylinder window of the cylinder body of the distribution sub-simulation module and enters the plunger cavity of the cylinder body, completing the inflow function of the high-pressure oil of the distribution plate; when the cylinder window of the cylinder body in the distribution sub-simulation module is connected with the low-pressure distribution window of the distribution plate, the oil in the plunger cavity of the cylinder body becomes low-pressure oil and flows from the cylinder window of the cylinder body of the distribution sub-simulation module into the low-pressure distribution window of the distribution plate, and then enters the oil passage of the distribution sub-guiding module and returns to the oil tank through the oil return loop, completing the outflow function of the low-pressure oil of the distribution plate; A torque sensor is installed on the transmission shaft; the torque sensor obtains the friction torque of the distribution pair interface through data collection and calibration calculation.

2. The in-situ testing device for the friction characteristics of the flow distribution interface of the inner curve radial piston hydraulic motor according to claim 1 is characterized in that: The flow distribution sub-simulated module has a flow distribution sub-simulated module self-aligning ball bearing, which is used to ensure that the flow distribution sub-simulated module, the flow distribution sub-flow guide module and the transmission shaft are always concentric.

3. The in-situ testing device for the friction characteristics of the flow distribution interface of the inner curve radial piston hydraulic motor according to claim 1 is characterized in that: The flow distribution pair virtual module has a flow distribution pair virtual module thrust cylindrical roller bearing, which is used to bear the axial force exerted on the cylinder body.

4. The in-situ testing device for the friction characteristics of the flow distribution interface of an inner curve radial piston hydraulic motor according to claim 1 is characterized in that: The flow distribution pair simulation module has a flow distribution state observation window, which is used to observe the flow field flow state of the flow distribution pair.

5. The in-situ testing device for the friction characteristics of the flow distribution interface of an inner-curve radial piston hydraulic motor according to claim 1, characterized in that: The loading chamber of the distribution pair simulation module is used to control the oil input pressure so that the loading pressure of the chamber generates a loading force on the transmission shaft, and the loading force is equal to the pressing force of the distribution plate.

6. The in-situ testing device for the friction characteristics of the flow distribution interface of an inner-curve radial piston hydraulic motor according to claim 1, characterized in that: The friction torque of the drive shaft and the transmission system connected to it when the valve plate is not working is obtained through the torque sensor test. The friction torque measured by the torque sensor when the valve plate is working is calibrated to eliminate the influence of the friction torque of the drive shaft and the transmission system connected to it on the friction torque of the valve pair, thereby realizing the calibration of the equivalent in-situ test friction torque.

7. A testing method for an in-situ testing device for the friction characteristics of the flow distribution interface of an inner curve radial piston hydraulic motor according to any one of claims 1 to 6, characterized in that: The method comprises the following steps: (1) According to the assembly sequence of the flow distribution sub-simulation module, install the tested distribution plate and the corresponding cylinder body at the corresponding positions of the flow distribution sub-simulation module, and adjust the initial matching clearance between the distribution plate and the cylinder body; (2) After the assembly of the flow distribution sub-simulation module is completed, its transmission shaft is connected to the torque sensor through a coupling. After it is fully installed, the flow distribution sub-simulation module is fixedly connected to the test bench frame by bolts; (3) Connect the oil inlet of the distribution pair virtual module cavity, the high-pressure oil inlet of the distribution pair, the oil return port of the distribution pair virtual module cavity, the oil port of the distribution pair loading circuit and the low-pressure oil return port of the distribution pair to the corresponding oil ports of the hydraulic system respectively, and install the pressure and temperature sensor of the distribution pair leakage port, the pressure and temperature sensor of the distribution pair high-pressure port, the pressure and temperature sensor of the distribution pair loading circuit and the pressure and temperature sensor of the distribution pair low-pressure port at the corresponding positions; (4) After the installation is completed, start the hydraulic system, fill the inner cavity of the distribution sub-simulation module with oil through the inner cavity oil inlet of the distribution sub-simulation module, and after the inner cavity of the distribution sub-simulation module is filled with oil, close the inner cavity oil inlet of the distribution sub-simulation module and open the inner cavity oil return port of the distribution sub-simulation module, and adjust the working pressure and oil temperature of the distribution plate; (5) Then start the motor and adjust the motor speed to change the working speed of the control cylinder; (6) Through the test process of the above steps (1) to (5), by adjusting the working pressure and the working speed, the friction characteristics of the distribution pair of the current distribution plate under different working conditions are tested; (7) After the above working condition test is completed, the hydraulic system is switched, the high-pressure oil inlet of the distribution pair is closed, so that the current distribution plate is in a non-distribution working state, and the oil port of the distribution pair loading circuit is opened. The oil pressure of the loading circuit is adjusted according to the clamping force of the distribution plate to keep it consistent with the residual clamping force of the distribution plate. The friction torque of the transmission shaft and its transmission system is obtained by testing, and the friction torque of the distribution pair can be obtained by subtracting it from the friction torque obtained in the test in step (6); (8) After the above tests are completed, remove the distribution plate under test and observe the wear condition of the distribution pair after the test under a microscope.

Images