Multi-station comprehensive performance test equipment for ball screw pair for automobile braking

Abstract

The invention discloses a multi-station comprehensive performance test device for a ball screw pair for automobile braking. The test equipment is used for carrying out comprehensive performance tests including service life, static efficiency and NVH (Noise Vibration and Harshness) on the ball screw pair, and comprises a plurality of stations which are respectively used for testing the comprehensive performance of different types of ball screw pairs. The test equipment comprises a lathe bed and a plurality of test equipment units arranged on the lathe bed, and the plurality of test equipment units are respectively in one-to-one correspondence with the plurality of stations; the test equipment unit comprises a driving mechanism, a loading mechanism and a guiding mechanism. The device is compact in layout and reliable in structure, can provide service life, static efficiency and NVH comprehensive performance tests for a plurality of ball screw pairs for automobile braking of different models at the same time, and greatly shortens the service life verification period of the ball screw pairs for automobile braking. On the basis, the output torque of the ball screw pair is measured through static efficiency testing equipment so as to calculate the static efficiency of the ball screw pair; axial and normal vibration acceleration signals of the ball screw pair are measured through the vibration acceleration sensor so as to judge the vibration condition of the ball screw pair.

Description

Technical Field

[0001] The present invention belongs to the technical field of rolling functional component testing, and particularly relates to a multi-station comprehensive performance testing device for ball screw pairs used in automotive braking. Background Technique

[0002] Compared with traditional trapezoidal screws, ball screws are widely used in fields such as machine tools, automobiles, aerospace, etc. due to their characteristics of high precision, high efficiency, and high reliability. In the automotive field, ball screw pairs can be used in the steering system, braking system, accelerator pedal, seat adjustment system, and window glass lifting system of automobiles to improve the precision, efficiency, and safety of automobiles. In recent years, with the popularization of new energy vehicles, the application of ball screw pairs in automotive braking systems has become more and more extensive. In the electro-hydraulic braking system (EHB), the hydraulic components slow down in response speed during long-term use, and the vacuum booster is gradually replaced by an electric booster mainly composed of a ball screw pair; in the electro-mechanical braking system (EMB), the motor provides braking force through a reducer and a ball screw pair. In the future, the market scale of ball screw pairs for automotive braking will increase significantly, becoming the focus of attention of domestic and foreign automotive parts manufacturers and ball screw manufacturers.

[0003] As a core safety component in the braking system, the life reliability of the ball screw pair for automotive braking directly determines the safety of the entire vehicle during driving. Therefore, the automotive field pays more attention to the service life of the ball screw; at the same time, since the ball screw pair is in a static state during braking, the static transmission efficiency of the ball screw pair is also highly concerned; the vibration and noise of the ball screw pair during operation will affect the riding comfort, so NVH is also a key factor to be considered. Existing testing equipment can only test a single performance of the ball screw pair, seriously affecting the development cycle of the ball screw for automotive braking. Summary of the Invention

[0004] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a multi-station comprehensive performance testing device for ball screw pairs used in automotive braking. The device provides four ball screw testing channels and can simultaneously test four different types of ball screws to improve the testing efficiency.

[0005] The technical solution to achieve the purpose of the present invention is: a multi-station comprehensive performance testing device for ball screw pairs used in automotive braking. The testing device conducts comprehensive performance tests on the ball screw pair, including life, static efficiency, and NVH. It includes multiple stations, which are respectively used to test the comprehensive performance of different types of ball screw pairs; the testing device includes a bed body, multiple testing device units arranged on the bed body, and a static efficiency and NVH testing device connected to the testing device units. The multiple testing device units correspond to the multiple stations one by one;

[0006] The test equipment unit includes:

[0007] A driving mechanism for driving the nut or screw sample under test to rotate, and measuring the output torque of the ball screw pair through a static efficiency test equipment.

[0008] A loading mechanism for providing stable linear loading to the ball screw and monitoring the magnitude of the loading force in real time.

[0009] A guiding mechanism for guiding the moving parts to move along a predetermined trajectory, bearing loads, and ensuring motion accuracy.

[0010] The bed body is used to provide a base surface with a certain level of accuracy for installing the guiding mechanism.

[0011] Furthermore, the test equipment uses the reaction force generated by a compression spring to perform axial loading on the ball screw pair.

[0012] Furthermore, the loading mechanism can provide a load that is always unidirectional and linearly increases with the increase of the compression distance, and adjusts the magnitude of the loading force by controlling the movement stroke of the screw and the stiffness of the spring.

[0013] Furthermore, the ball screw pair adapted to the test equipment at least includes: small ball screw pairs with a length not exceeding 150 mm used in automotive electro-hydraulic braking systems (i.e., EHB) and electromechanical braking systems (i.e., EMB).

[0014] Furthermore, the test equipment includes at least four workstations, namely Workstation 1, Workstation 2, Workstation 3, and Workstation 4. Workstation 1 is used to test the first type of EHB ball screw pair, Workstation 2 is used to test the second type of EHB ball screw pair, Workstation 3 is used to test the third type of EHB ball screw pair, and Workstation 4 is used to test the first type of EMB ball screw pair;

[0015] The first type of EHB ball screw pair at least includes a screw and a nut, and the head of its screw has a thread; the second type of EHB ball screw pair at least includes a screw and a nut, and the head of its screw does not have a thread; the third type of EHB ball screw pair at least includes a planetary pin, a four-point contact bearing, a nut, and a screw, and the nut serves as the inner ring of the bearing; the first type of EMB ball screw pair at least includes a screw and a nut, and a U-shaped groove is opened at the bottom of the screw.

[0016] Furthermore, the driving mechanism includes a servo motor, a coupling, a motor bearing seat, and an ultra-precision angular contact thrust ball bearing;

[0017] For the first station, the driving mechanism further includes a first transmission shaft, a first bearing end cover, a locking nut, a first sensor connector, a sensor connector support seat, and a shrink disc;

[0018] For the second station, the difference between the driving mechanism corresponding to the second station and that of the first station is that it further includes a transmission adapter plate which is fixed on the second transmission shaft corresponding to the second station;

[0019] For the third station, the driving mechanism further includes a third transmission shaft, a third bearing end cover, and a third sensor connector;

[0020] For the fourth station, the driving mechanism further includes a fourth transmission shaft, a fourth bearing end cover, and a nut support seat;

[0021] The servo motor is installed on the motor bearing seat, and the motor bearing seat is fixed on the guiding mechanism. The motor shaft is connected to the transmission shafts corresponding to each station through the coupling. Each transmission shaft is installed in the motor bearing seat through the ultra-precision angular contact thrust ball bearing, and the outer ring of the ultra-precision angular contact ball bearing is fixed in the motor bearing seat through the bearing end covers of each station; wherein, the inner ring of the ultra-precision angular contact ball bearing corresponding to the first station and the second station also needs to be fixed on the corresponding transmission shaft through the locking nut;

[0022] For the first station, the thread at the head of the screw of the first type of EHB ball screw pair is threadedly connected to the first transmission shaft, and the bottom of its nut also has a thread and is threadedly connected to one end of the first sensor connector. At the same time, the outside of the first sensor connector is connected to the sensor connector support seat through the shrink disc for keyless connection, and the sensor connector support seat is fixed on the slider of the guiding mechanism. In summary, the rotational motion of the screw is converted into the linear motion of the nut; for the second station, the difference from the first station is that the screw of the second type of EHB ball screw pair is fixed to the transmission adapter plate to transmit torque;

[0023] For the third station, the nut of the third type of EHB ball screw pair serves as the inner ring of the bearing, and a raceway is machined on its outer circle; the third bearing end cover fixes the outer ring of the four-point contact bearing in the motor bearing seat. The output end of the third transmission shaft is machined with a pin hole, and the ball screw pair is connected to the third transmission shaft through at least three planetary pins. The third transmission shaft drives the nut to complete rotational motion under the support of the internal bearing through the planetary pins, thereby converting it into the linear motion of the screw;

[0024] For station four, the output end of the fourth transmission shaft has a U-shaped convex surface, which is engaged with the U-shaped groove at the bottom of the lead screw of the first type of EMB ball screw pair and is axially positioned with the fourth transmission shaft; both sides of the nut of the first type of EMB ball screw pair are provided with anti-rotation devices. The nut is installed on the nut support seat, and the nut support seat is fixed on the slider of the guiding mechanism. Grooves are also formed on both sides of the nut support seat to cooperate with the anti-rotation devices, thereby enabling the fourth transmission shaft to drive the lead screw to rotate, and then converting it into a linear motion of the nut;

[0025] The driving mechanism has a certain rotational accuracy, anti-torsion and anti-bending capabilities to stably drive the transmission shaft to rotate smoothly within the bearing seat.

[0026] Further, the loading mechanism includes a tension sensor, a spring guide rod, a spring pressing plate, a spring seat, a loading spring and a slider clamping strip;

[0027] For station one and station two, the other ends of the corresponding first sensor connector and second sensor connector are respectively connected to one threaded end of the tension sensor, and the other end of the tension sensor is fixed on the spring pressing plate; two spring guide rods are installed in the spring seat and are connected to the tail of the spring seat; two loading springs are also installed in the spring seat and are respectively sleeved on the two spring guide rods; the other ends of the spring guide rods are sleeved on the spring pressing plate, and both the spring pressing plate and the spring seat are fixed on the slider of the guiding mechanism; on one side of the tail of the spring seat, there is provided the slider clamping strip installed on the guide rail of the guiding mechanism, and the guide rail and the slider clamping strip are fixed by screws, and the friction between the screws and the slider clamping strip is used to bear the spring loading force to fix the spring seat;

[0028] For station three, there is a groove at the front end of the third sensor connector, which is positioned and engaged with the convex surface of the lead screw end face. The other side of the third sensor connector is connected to the tension sensor;

[0029] For station four, the front end of the tension sensor is directly connected to the nut support seat.

[0030] Further, the groove at the front end of the third sensor connector and the convex surface of the lead screw end face are simultaneously fastened by screws in the threaded holes on the side of the third sensor connector.

[0031] Further, the bed body includes a marble slab, a welded frame plate and a bottom support seat. The marble slab is installed on the welded frame plate; both ends of the bottom of the welded frame plate are respectively fixed on the ground through the bottom support seats.

[0032] Furthermore, the guiding mechanism includes a slider, a guide rail and a guide rail seat; the slider is installed on the guide rail and can slide along the guide rail, the guide rail is installed on the guide rail seat, and the guide rail seat is installed on the marble slab of the machine tool bed.

[0033] Compared with the prior art, the present invention has the following remarkable advantages:

[0034] 1) The test equipment of the present invention has a compact and reasonable structural layout, a large load-bearing capacity and stable support, provides at least four ball screw test channels, can simultaneously perform comprehensive performance tests on at least four ball screw pairs of different models, improves the test efficiency, and is convenient for installation and disassembly.

[0035] 2) By referring to relevant literature, the axial loading device of the ball screw pair, such as Chinese Patent CN 110657987, performs loading through a horizontal ball screw, which has a relatively complex structure and cannot provide a linear loading force. However, the test equipment of the present invention uses the reaction force generated by the spring when the spring is compressed to axially load the automotive ball screw pair, can provide a unidirectional loading force that linearly increases with the increase of the compression distance, has a stable loading force, is convenient for replacement and has a low use cost.

[0036] 3) The test equipment of the present invention can complete the NVH test of the ball screw pair for automotive braking through an external acceleration sensor, a vibration acquisition system and a vibration noise meter.

[0037] 4) The test equipment of the present invention can collect the input axial force in real time through a tension sensor, and calculate the static efficiency of the measured ball screw pair by collecting the output torque through a static efficiency test device.

[0038] The present invention will be further described in detail below with reference to the accompanying drawings. Description of the Drawings

[0039] Figure 1 It is a schematic diagram of the overall structure of the multi-station comprehensive performance test equipment for the ball screw pair for automotive braking in an embodiment.

[0040] Figure 2 It is an exploded structural schematic diagram of the transmission mechanism of the first station of the multi-station comprehensive performance test equipment for the ball screw pair for automotive braking in an embodiment.

[0041] Figure 3 It is an exploded structural schematic diagram of the transmission mechanism of the second station of the multi-station comprehensive performance test equipment for the ball screw pair for automotive braking in an embodiment.

[0042] Figure 4 It is an exploded structural schematic diagram of the transmission mechanism of the third station of the multi-station comprehensive performance test equipment for the ball screw pair for automotive braking in an embodiment.

[0043] Figure 5 It is an exploded structural schematic diagram of a four-station transmission mechanism of a multi-station comprehensive performance test device for a ball screw pair used in automobile braking in an embodiment.

[0044] Figure 6 It is an exploded structural schematic diagram of a loading mechanism of a multi-station comprehensive performance test device for a ball screw pair used in automobile braking in an embodiment.

[0045] Figure 7 It is an exploded structural schematic diagram of a guiding mechanism and a bed of a multi-station comprehensive performance test device for a ball screw pair used in automobile braking in an embodiment.

[0046] Figure 8 It is an exploded structural schematic diagram of a ball screw sample of model 1203-2 to be measured in a multi-station comprehensive performance test device for a ball screw pair used in automobile braking in an embodiment.

[0047] Figure 9 It is an exploded structural schematic diagram of a ball screw sample of model 1803.3 to be measured in a multi-station comprehensive performance test device for a ball screw pair used in automobile braking in an embodiment.

[0048] Reference numerals: 1. Driving mechanism; 2. Loading mechanism; 3. Guiding mechanism; 4. Bed; 5. Servo motor; 6. Motor bearing seat; 7. Coupling; 8. Locking nut; 9. Ultra-precision angular contact thrust ball bearing; 10. First bearing end cover; 11. First transmission shaft; 12. Ball screw of model 1203-1; 13. Expansion sleeve; 14. Sensor joint support seat; 15. First sensor joint; 16. Second transmission shaft; 17. Transmission adapter plate; 18. Ball screw of model 1203-2; 19. Second sensor joint; 20. Third transmission shaft; 21. Third bearing end cover; 22. Ball screw of model 1803.3; 23. Third sensor joint; 24. Fourth bearing end cover; 25. Fourth transmission shaft; 26. Ball screw of model 45.804; 27. Nut support seat; 28. Slider clamping strip; 29. Spring seat; 30. Spring guide rod; 31. Loading spring; 32. Spring pressure plate; 33. Tensile sensor; 34. Slider; 35. Guide rail; 36. Guide rail seat; 37. Marble plate; 38. Welded frame plate; 39. Bottom support seat; 40. Nut of model 1203-2; 41. Screw of model 1203-2; 42. Screw of model 1803.3; 43. Nut of model 1803.3; 44. Four-point contact bearing; 45. Planet pin. Detailed implementation manners

[0049] In order to make the objectives, technical solutions and advantages of the present application clearer and more understandable, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0050] It should be noted that if there are directional indications (such as up, down, left, right, front, back...) involved in the embodiments of the present invention, then such directional indications are only used to explain the relative positional relationship, movement conditions, etc. between components in a certain specific posture (as shown in the attached drawings). If this specific posture changes, then the directional indications will also change accordingly.

[0051] In addition, if there are descriptions such as "first", "second", etc. involved in the embodiments of the present invention, then such descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first", "second" can explicitly or implicitly include at least one such feature. In addition, the technical solutions between various embodiments can be combined with each other, but it must be based on the fact that those of ordinary skill in the art can implement it. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0052] In addition, if there are descriptions such as "spring", "screw", etc. involved in the embodiments of the present invention, then such descriptions of "spring", "screw", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "spring", "screw" can explicitly or implicitly include at least one such feature. In addition, the technical solutions between various embodiments can be combined with each other, but it must be based on the fact that those of ordinary skill in the art can implement it. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0053] In one embodiment, in combination with Figures 1 to 9 , a multi-station comprehensive performance test device for a ball screw pair used in automotive braking is provided. The test device conducts comprehensive performance tests on the ball screw pair, including life, static efficiency, and NVH (including noise, vibration, and squeakiness) vibration. It includes multiple stations, which are respectively used to test the comprehensive performance of different types of ball screw pairs; the test device includes a bed body 4, a plurality of test device units arranged on the bed body 4, and a static efficiency and NVH test device connected to the test device units. The multiple test device units respectively correspond to the multiple stations one by one;

[0054] The test device unit includes:

[0055] A driving mechanism 1, which is used to drive the nut or screw sample under test to rotate, and the output torque of the ball screw pair is measured through a static efficiency test device;

[0056] The loading mechanism 2 is used to provide stable linear loading for the ball screw and monitor the magnitude of the loading force in real time;

[0057] By analyzing the magnitude of the collected loading force, the static efficiency of the measured ball screw pair can be calculated through the static efficiency calculation formula;

[0058] The guiding mechanism 3 is used to guide the moving parts to move along a predetermined trajectory, bear the load and ensure the motion accuracy;

[0059] The bed body 4 is used to provide a base surface with a certain level of accuracy to install the guiding mechanism 3.

[0060] Further, in one embodiment, the

[0061] Further, in one embodiment, the test equipment uses the reaction force generated by the compression spring to perform axial loading on the ball screw pair.

[0062] Further, in one embodiment, the loading mechanism can provide a load that is always unidirectional and linearly increases with the increase of the compression distance, and the magnitude of the loading force is adjusted by controlling the movement stroke of the screw and the stiffness of the spring.

[0063] Further, in one embodiment, the ball screw pairs adapted to the test equipment at least include: small ball screw pairs with a length not exceeding 150 mm used in automotive electronic hydraulic brake systems (i.e., EHB) and electromechanical brake systems (i.e., EMB).

[0064] Further, in one embodiment, the test equipment at least includes four workstations, namely Workstation 1, Workstation 2, Workstation 3 and Workstation 4. Workstation 1 is used to test the first type of EHB ball screw pair, Workstation 2 is used to test the second type of EHB ball screw pair, Workstation 3 is used to test the third type of EHB ball screw pair, and Workstation 4 is used to test the first type of EMB ball screw pair;

[0065] The first type of EHB ball screw pair at least includes a screw and a nut, and the head of its screw has a thread; the second type of EHB ball screw pair at least includes a screw and a nut, and the head of its screw does not have a thread; the third type of EHB ball screw pair at least includes a planetary pin, a four-point contact bearing, a nut and a screw, and the nut serves as the inner ring of the bearing; the first type of EMB ball screw pair at least includes a screw and a nut, and the bottom of the screw is provided with but not limited to a U-shaped groove.

[0066] Preferably, the first type of EHB ball screw pair and the second type of EHB ball screw pair are 1203 model EHB ball screw pairs, the third type of EHB ball screw pair is 1803.3 model EHB ball screw pair, and the first type of EMB ball screw pair is 45.804 model EMB ball screw pair.

[0067] Furthermore, in one of the embodiments, the driving mechanism 1 includes a servo motor 5, a coupling 7, a motor bearing seat 6, and an ultra-precision angular contact thrust ball bearing 9;

[0068] For the first station, the driving mechanism 1 further includes a first transmission shaft 11, a first bearing end cover 10, a locking nut 8, a first sensor connector 15, a sensor connector support seat 14, and a shrink disc 13;

[0069] For the second station, the difference between the driving mechanism corresponding to the second station and that of the first station is that it further includes a transmission adapter plate 17, which is fixed on the second transmission shaft 16 corresponding to the second station;

[0070] For the third station, the driving mechanism 1 further includes a third transmission shaft 20, a third bearing end cover 21, and a third sensor connector 23;

[0071] For the fourth station, the driving mechanism 1 further includes a fourth transmission shaft 25, a fourth bearing end cover 24, and a nut support seat 27;

[0072] The servo motor 5 is installed on the motor bearing seat 6, the motor bearing seat 6 is fixed on the guiding mechanism 3, the motor shaft is connected to the transmission shafts corresponding to each station through the coupling 7, each transmission shaft is installed in the motor bearing seat 6 through the ultra-precision angular contact thrust ball bearing 9, and the outer ring of the ultra-precision angular contact ball bearing 9 is fixed in the motor bearing seat 6 through the bearing end covers of each station; among them, the inner ring of the ultra-precision angular contact ball bearing 9 corresponding to the first station and the second station also needs to be fixed on the corresponding transmission shaft through the locking nut 8;

[0073] It should be noted here that the multi-station comprehensive performance test equipment for ball screw pairs used in automobile braking mainly bears axial forces during testing, and since the servo motor 5 is directly connected to the transmission shaft through the coupling 7, the rotational speed of the transmission shaft will be relatively high. Therefore, the present invention selects the ultra-precision angular contact thrust ball bearing 9 to support the transmission shaft. The ultra-precision angular contact thrust ball bearing 9 not only has high precision, but also can bear loads in both axial and radial directions, and is beneficial for high-speed rotation.

[0074] For the first station, the thread at the head of the screw of the first type of EHB ball screw pair is threadedly connected to the first transmission shaft 11. The bottom of its nut also has a thread and is threadedly connected to one end of the first sensor connector 15. At the same time, the outside of the first sensor connector 15 is keylessly connected to the sensor connector support seat 14 through the expansion sleeve 13. The sensor connector support seat 14 is fixed on the slider 34 of the guiding mechanism. In summary, the rotational motion of the screw is converted into the linear motion of the nut. For the second station, the difference from the first station is that the screw of the second type of EHB ball screw pair is fixed to the transmission adapter plate 17 to transmit torque.

[0075] For the third station, the nut of the third type of EHB ball screw pair serves as the inner ring of the bearing, and a raceway is machined on its outer circle. The third bearing end cover 21 fixes the outer ring of the four-point contact bearing in the motor bearing seat 6. The output end of the third transmission shaft 20 is machined with a pin hole. The ball screw pair is connected to the third transmission shaft 20 through at least three planetary pins. The third transmission shaft 20 drives the nut to complete rotational motion under the support of the internal bearing through the planetary pins, thereby converting it into the linear motion of the screw.

[0076] For the fourth station, the output end of the fourth transmission shaft 25 has a U-shaped convex surface, which is matched with the U-shaped groove (not limited to) at the bottom of the screw of the first type of EMB ball screw pair and is axially located with the fourth transmission shaft 25. Anti-rotation devices are provided on both sides of the nut of the first type of EMB ball screw pair. The nut is installed on the nut support seat 27. The nut support seat 27 is fixed on the slider 34 of the guiding mechanism. Grooves are also provided on both sides of the nut support seat 27 to cooperate with the anti-rotation devices. Thus, the fourth transmission shaft 25 drives the screw to rotate, thereby converting it into the linear motion of the nut. According to the test requirements of different screws, different axial loading forces and motion strokes are applied to calculate the spring stiffness required for loading, and different stiffness springs are selected to adapt to different test environments.

[0077] The driving mechanism has a certain rotational accuracy, anti-torsion and anti-bending capabilities to stably drive the transmission shaft to rotate smoothly in the bearing seat.

[0078] Preferably, in some embodiments, the diameter and effective length of the threaded hole of the first sensor connector 15 and the diameter and effective length of the threaded hole of the first transmission shaft 11 can be changed to adapt to ball screw pairs with similar structures to the 1203-1 model EHB ball screw pair, so that they can be installed and tested.

[0079] Preferably, in some embodiments, the diameter and effective thread length of the threaded hole of the second sensor joint 19, the diameter and effective thread length of the threaded hole of the second transmission shaft 16, the shape and size of the middle through-hole of the transmission adapter plate 17 and the size of the side threaded hole are all adjustable, for adapting to a ball screw pair with a similar structure to the 1203-2 model EHB ball screw pair, so that it can be installed and tested.

[0080] Preferably, in some embodiments, the aperture of the motor bearing seat 6, the size of the third bearing end cover 21, and the size of the groove of the third sensor joint 23 are all adjustable, for adapting to a ball screw pair with a similar structure to the 1803.3 model EHB ball screw pair, so that it can be installed and tested.

[0081] Preferably, in some embodiments, the aperture and depth of the hole where the nut support seat 27 cooperates with the nut, the size of the side groove, and the size of the fourth transmission shaft 25 are all adjustable, for adapting to a ball screw pair with a similar structure to the 45.804 model EHB ball screw pair, so that it can be installed and tested.

[0082] Further, in one of the embodiments, the loading mechanism includes a tension sensor 33, a spring guide rod 30, a spring pressing plate 32, a spring seat 29, a loading spring 31, and a slider clamping bar 28;

[0083] For station one and station two, the other ends of the first sensor joint 15 and the second sensor joint 19 respectively corresponding thereto are connected to the threaded end of the tension sensor 33, and the other end of the tension sensor 33 is fixed on the spring pressing plate 32; two spring guide rods 30 are installed in the spring seat 29 and are connected to the tail of the spring seat 29; two loading springs 31 are also installed in the spring seat 29 and respectively sleeved on the two spring guide rods 30; the other end of the spring guide rod 30 is sleeved on the spring pressing plate 32, and both the spring pressing plate 32 and the spring seat 29 are fixed on the slider 34 of the guiding mechanism; on one side of the tail of the spring seat 29, there is provided the slider clamping bar 28 installed on the guide rail 35 of the guiding mechanism, and the guide rail 35 and the slider clamping bar 28 are fixed by screws, and the spring loading force is borne by the friction between the screws and the slider clamping bar 28 to fix the spring seat 29;

[0084] For station three, there is a groove at the front end of the third sensor joint 23, which is in positioning fit with the convex surface of the screw end face, and the other side of the third sensor joint 23 is connected to the tension sensor 33;

[0085] For station four, the front end of the tension sensor 33 is directly connected to the nut support seat 27.

[0086] According to the test requirements of different lead screws, axial loading forces and movement strokes are applied to calculate the spring stiffness required for loading, and springs with different stiffnesses are selected to adapt to different test environments.

[0087] Preferably, in some embodiments, the groove at the front end of the third sensor joint 23 and the convex surface of the lead screw end face are simultaneously fastened by screws in the threaded holes on the side of the third sensor joint 23.

[0088] Further, in one of the embodiments, the bed body 4 includes a marble plate 37, a welded frame plate 38, and a bottom support base 39. The marble plate 37 is installed on the welded frame plate 38; both ends of the bottom of the welded frame plate 38 are fixed to the ground through the bottom support base 39.

[0089] Further, in one of the embodiments, the guiding mechanism includes a slider 34, a guide rail 35, and a guide rail seat 36. The slider 34 is installed on the guide rail 35 and can slide along the guide rail 35. The above parts can move freely on the guide rail 35 for installation and use. The guide rail 35 is installed on the guide rail seat 36, and the guide rail seat 36 is installed on the marble plate 37 of the bed body 4.

[0090] It should be noted that the fixed installation mentioned above adopts but is not limited to methods such as bolts and screws.

[0091] When the comprehensive performance test equipment for ball screw pairs of the present invention is working, in accordance with Figure 1The structure successively installs a driving mechanism, a loading mechanism, and a sample ball screw to be measured; selects a loading spring with appropriate stiffness according to the sample test requirements, and adjusts the position of the nut to control the appropriate initial compression force of the spring; sets parameters such as the reciprocating stroke, the rotational speed of the nut or the screw, the forward and backward delay times, and the running-in times on the software interface of the industrial control computer. Then, turn on the servo motor switch. The output shaft of the servo motor is connected to the transmission shaft through a coupling, and the transmission shaft is connected to the screw through a thread to drive the screw to complete a rotational motion on the support of the internal bearing and finally be converted into a linear motion of the nut. Or connect the nut through a planetary pin to drive the nut to complete a rotational motion on the support of the internal bearing and finally be converted into a linear motion of the screw. During the extension process of the nut or the screw, the sensor joint is pushed to drive the tension sensor to press the loading spring. The compressed loading spring generates an elastic force to provide a linear load for the ball screw. The magnitude of the loading force can be adjusted by controlling the movement stroke of the screw or the nut and the stiffness of the spring. The magnitude of the loading force can be displayed in real time on the software interface of the industrial control computer. By analyzing the magnitude of the loading force collected in real time and providing an external fixture to calculate the output torque, the static efficiency of the sample to be measured can be calculated. In addition, the NVH vibration test of the ball screw pair for automotive braking is completed through an external vibration acceleration sensor, a vibration acquisition system, and a vibration noise meter.

[0092] The above shows and describes the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. What is described in the above embodiments and the specification only illustrates the principles of the present invention. Without departing from the spirit and scope of the present invention, any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A multi-station comprehensive performance testing equipment for ball screw pairs for automobile brakes, characterized in that: The testing device performs a comprehensive performance test on a ball screw pair including life, static efficiency and NVH, and comprises a plurality of workstations, respectively used to test the comprehensive performance of different types of ball screw pairs; the testing device comprises a bed (4), a plurality of testing device units arranged on the bed (4), and static efficiency and NVH testing devices connected to the testing device units, and the plurality of testing device units correspond one to one to the plurality of workstations respectively; The test equipment unit comprises: A driving mechanism (1) is used to drive the nut or screw sample to be tested to rotate, and to measure the output torque of the ball screw pair through a static efficiency test device; The loading mechanism (2) is used to provide a stable linear load to the ball screw and monitor the magnitude of the loading force in real time; A guide mechanism (3) is used to guide the moving parts to move along a predetermined trajectory, bear the load and ensure the movement accuracy; The bed (4) is used to provide a base surface with a certain horizontal accuracy for installing the guide mechanism (3).

2. The multi-station comprehensive performance testing equipment for ball screw pairs for automobile brakes according to claim 1 is characterized in that: The test device utilizes the reaction force generated by the compression spring to axially load the ball screw pair.

3. The multi-station comprehensive performance testing equipment for ball screw pairs for automobile brakes according to claim 2 is characterized in that: The loading mechanism can provide a load that is always unidirectional and increases linearly with the increase of the compression distance, and the size of the loading force is adjusted by controlling the movement stroke of the lead screw and the stiffness of the spring.

4. The multi-station comprehensive performance testing equipment for ball screw pairs for automobile brakes according to claim 1 is characterized in that: The ball screw pairs adapted to the test equipment include at least: small ball screw pairs with a length not exceeding 150 mm used in automobile electronic hydraulic brake systems (EHB) and electronic mechanical brake systems (EMB).

5. The multi-station comprehensive performance testing equipment for ball screw pairs for automobile brakes according to claim 1, characterized in that: The testing equipment includes at least four stations, namely station one, station two, station three and station four, the station one is used to test the first type of EHB ball screw pair, the station two is used to test the second type of EHB ball screw pair, the station three is used to test the third type of EHB ball screw pair, and the station four is used to test the first type of EMB ball screw pair; The first type of EHB ball screw pair includes at least a screw and a nut, and its screw head has a thread; the second type of EHB ball screw pair includes at least a screw and a nut, and its screw head does not have a thread; the third type of EHB ball screw pair includes at least a planetary pin, a four-point contact bearing, a nut and a screw, and the nut serves as the inner ring of the bearing; the first type of EMB ball screw pair includes at least a screw and a nut, and a U-shaped groove is opened at the bottom of the screw.

6. The multi-station comprehensive performance testing equipment for ball screw pairs for automobile brakes according to claim 5, characterized in that: The driving mechanism (1) comprises a servo motor (5), a coupling (7), a motor bearing seat (6) and an ultra-precision angular contact thrust ball bearing (9); For the workstation 1, the driving mechanism (1) further comprises a first transmission shaft (11), a first bearing end cover (10), a locking nut (8), a first sensor connector (15), a sensor connector support seat (14) and a locking sleeve (13); The difference between the driving mechanism of the workstation 2 and that of the workstation 1 is that it further comprises a transmission adapter plate (17) which is fixed on the second transmission shaft (16) corresponding to the workstation 2; For the workstation three, the driving mechanism (1) further comprises a third transmission shaft (20), a third bearing end cover (21) and a third sensor connector (23); For the workstation four, the driving mechanism (1) further comprises a fourth transmission shaft (25), a fourth bearing end cover (24) and a nut support seat (27); The servo motor (5) is mounted on the motor bearing seat (6), the motor bearing seat (6) is fixed on the guide mechanism (3), the motor shaft is connected to the transmission shaft corresponding to each workstation through the coupling (7), each transmission shaft is mounted in the motor bearing seat (6) through the ultra-precision angular contact thrust ball bearing (9), and the outer ring of the ultra-precision angular contact ball bearing (9) is fixed in the motor bearing seat (6) through the bearing end cover of each workstation; wherein, the inner ring of the ultra-precision angular contact ball bearing (9) corresponding to the workstation one and the workstation two is also required to be fixed on the corresponding transmission shaft through the locking nut (8); For the workstation 1, the thread of the lead screw head of the first type EHB ball screw pair is threadedly connected to the first transmission shaft (11), and the bottom of the nut thereof also has a thread, which is threadedly connected to one end of the first sensor connector (15), and at the same time, the outside of the first sensor connector (15) is keylessly connected to the sensor connector support seat (14) through the expansion sleeve (13), and the sensor connector support seat (14) is fixed on the slider (34) of the guide mechanism, so as to realize the conversion of the rotational motion of the lead screw into the linear motion of the nut; for the workstation 2, the difference from the workstation 1 is that the lead screw of the second type EHB ball screw pair is fixed to the transmission adapter plate (17) to transmit torque; For station three, the nut of the third type of EHB ball screw pair serves as the inner ring of the bearing, and a raceway is machined on its outer circle; the third bearing end cover (21) fixes the outer ring of the four-point contact bearing in the motor bearing seat (6), and the output end of the third transmission shaft (20) is machined with a pin hole, and the ball screw pair is connected to the third transmission shaft (20) through at least three planetary pins. The third transmission shaft (20) drives the nut through the planetary pins to complete the rotational motion under the support of the internal bearing, thereby converting it into the linear motion of the screw; For station four, the output end of the fourth transmission shaft (25) has a U-shaped raised surface, which cooperates with the U-shaped groove at the bottom of the screw of the first type EMB ball screw pair, and is shoulder-positioned with the fourth transmission shaft (25); the nut of the first type EMB ball screw pair has anti-rotation devices on both sides, the nut is installed on a nut support seat (27), the nut support seat (27) is fixed on the slider (34) of the guide mechanism, and grooves are also provided on both sides of the nut support seat (27) to cooperate with the anti-rotation device, thereby realizing that the fourth transmission shaft (25) drives the screw to rotate, thereby converting it into linear motion of the nut; The driving mechanism has certain rotation accuracy and anti-torsion and bending capabilities, so as to stably drive the transmission shaft to rotate smoothly in the bearing seat.

7. The multi-station comprehensive performance testing equipment for ball screw pairs for automobile brakes according to claim 6, characterized in that: The loading mechanism comprises a tension sensor (33), a spring guide rod (30), a spring pressure plate (32), a spring seat (29), a loading spring (31) and a slider clamping strip (28); For station one and station two, the other ends of the first sensor connector (15) and the second sensor connector (19) respectively corresponding to the first and second sensor connectors are connected to one end of the thread of the tension sensor (33), and the other end of the tension sensor (33) is fixed on the spring pressure plate (32); two spring guide rods (30) are installed in the spring seat (29) and connected to the tail of the spring seat (29); two loading springs (31) are also installed in the spring seat (29) and are respectively sleeved on the two spring guide rods (30); The other end of the spring guide rod (30) is sleeved on the spring pressure plate (32), and the spring pressure plate (32) and the spring seat (29) are both fixed on the slider (34) of the guide mechanism; on one side of the tail of the spring seat (29), there is the slider clamping strip (28) installed on the guide rail (35) of the guide mechanism, and the guide rail (35) and the slider clamping strip (28) are fixed by screws, and the friction between the screws and the slider clamping strip (28) is used to bear the spring loading force to fix the spring seat (29); For station three, a groove is provided at the front end of the third sensor connector (23), which is positioned and matched with the raised surface of the end face of the lead screw, and the other side of the third sensor connector (23) is connected to the tension sensor (33); For station four, the front end of the tension sensor (33) is directly connected to the nut support seat (27).

8. The multi-station comprehensive performance testing equipment for ball screw pairs for automobile brakes according to claim 7, characterized in that: The groove at the front end of the third sensor connector (23) and the convex surface at the end face of the lead screw are fastened together by screws in the threaded holes on the side faces of the third sensor connector (23).

9. The multi-station comprehensive performance testing equipment for ball screw pairs for automobile brakes according to claim 1, characterized in that: The bed (4) comprises a marble slab (37), a welded frame plate (38) and a bottom support seat (39); the marble slab (37) is mounted on the welded frame plate (38); and the bottom ends of the welded frame plate (38) are respectively fixed to the ground via the bottom support seats (39).

10. The multi-station comprehensive performance testing equipment for ball screw pairs for automobile brakes according to claim 1, characterized in that: The guide mechanism comprises a slider (34), a guide rail (35) and a guide rail seat (36); the slider (34) is mounted on the guide rail (35) and can slide along the guide rail (35); the guide rail (35) is mounted on the guide rail seat (36); and the guide rail seat (36) is mounted on a marble slab (37) of the bed (4).

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