A vibration damper friction test device

Abstract

The present invention discloses a shock absorber friction force test device, which relates to the field of shock absorber testing technology and includes a frame; a three-degree-of-freedom platform for driving a workbench to move along the X-axis, along the Y-axis, and rotate around the Z-axis; a suspension mechanism including a mounting frame, a shock absorber, a swing arm assembly, and a wheel; the mounting frame is arranged on the workbench; one end of the shock absorber is connected to the swing arm assembly, and the other end of the shock absorber is connected to the mounting frame; a displacement sensor and a force sensor are provided on the shock absorber; a driving mechanism for driving the wheel to rotate; a bearing assembly for bearing the wheel; a vibration mechanism, which is arranged on the frame and is used to drive the bearing platform to vibrate up and down; and a processor. The shock absorber friction force test device of the present invention can effectively simulate the state of the shock absorber in real working conditions, and then use the displacement sensor and force sensor to respectively record the excitation velocity and damping force of the shock absorber, so as to analyze the friction force experienced by the shock absorber in real working conditions.

Description

Technical Field

[0001] The present invention relates to the technical field of shock absorber testing, in particular to a shock absorber friction force testing device. Background Art

[0002] Shock absorbers are widely used in automobiles. They can suppress the shock caused by the spring rebounding after absorbing shock and the impact from the road surface to improve the driving smoothness of the car. Shock absorbers need to undergo friction testing before being put on the market. In the existing technology, technicians usually use test equipment to apply vibration parallel to the shock absorber axis to the shock absorber, and apply lateral force perpendicular to the shock absorber axis to the shock absorber to detect the friction of the shock absorber. However, during the actual driving of the car, the working conditions of the shock absorber are relatively complex. In addition to its own axial expansion and contraction deformation, the shock absorber may also experience deflection deformation and other phenomena.

[0003] The test device in the prior art cannot test the friction force experienced by the shock absorber in real working conditions. Summary of the Invention

[0004] The main purpose of the present invention is to provide a vibration damper friction test device, aiming to solve the technical problem that the test device in the prior art cannot test the friction conditions of the vibration damper in real working conditions.

[0005] To achieve the above-mentioned object, the present invention provides a vibration damper friction force testing device, comprising:

[0006] frame;

[0007] A three-degree-of-freedom platform, one end of which is arranged on the frame and the other end of which is provided with a workbench; the three-degree-of-freedom platform is used to drive the workbench to move along the X-axis, move along the Y-axis, and rotate around the Z-axis;

[0008] The suspension mechanism includes a mounting frame, a shock absorber, a swing arm assembly, and a wheel; the mounting frame is disposed on the workbench; one end of the swing arm assembly is connected to the mounting frame, and the other end of the swing arm assembly is rotatably connected to the wheel; one end of the shock absorber is connected to the swing arm assembly, and the other end of the shock absorber is connected to the mounting frame; a displacement sensor and a force sensor are provided on the shock absorber; the displacement sensor is used to detect the excitation velocity of the shock absorber; and the force sensor is used to detect the damping force applied to the shock absorber;

[0009] a driving mechanism, disposed on the frame and used to drive the wheel to rotate;

[0010] The bearing assembly comprises a bearing platform and a plurality of rotating rollers rotatably connected to the bearing platform; wherein the wheels abut against the rotating rollers;

[0011] a vibration mechanism, the vibration mechanism being arranged on the frame and being used to drive the carrying platform to vibrate up and down;

[0012] a processor, the three-degree-of-freedom platform, the driving mechanism, the displacement sensor, the force sensor, and the vibration mechanism being electrically connected to the processor;

[0013] Based on the excitation velocity and damping force of the shock absorber, the friction force of the shock absorber is calculated using a friction force algorithm, which is:

[0014] F p =f c sgn(v0)+c m v0;

[0015] Among them, F p represents the damping force, f c represents friction, c m represents the viscous term of mechanical damping, sgn represents the sign function, and v0 represents the excitation velocity of the shock absorber.

[0016] Optionally, the shock absorber includes a first cylinder, a second cylinder, a shock absorbing spring, a screw, a transmission unit and a generator;

[0017] One end of the first cylinder is connected to the mounting bracket, and the other end of the first cylinder is slidably sleeved in the second cylinder; a positioning block is provided on the outside of the second cylinder; an end of the second cylinder away from the first cylinder is connected to the swing arm assembly; the vibration damping spring is sleeved on the outside of the first cylinder, one end of the vibration damping spring abuts against the first cylinder, and the other end of the vibration damping spring abuts against the positioning block;

[0018] One end of the screw extends into the first cylinder and is threadedly connected to the first cylinder, and the other end of the screw is in transmission connection with the transmission unit; the transmission unit is used to convert the forward and reverse rotation of the screw into the forward rotation of the generator shaft, and the forward rotation state of the generator is the power generation state.

[0019] Optionally, the transmission unit includes a first bevel gear, a second bevel gear, a third bevel gear, a first one-way bearing, and a second one-way bearing;

[0020] A shell is provided at one end of the second cylinder away from the first cylinder, and the transmission unit is located in the inner cavity of the shell; the first bevel gear and the second bevel gear are both connected to the screw for transmission, and the first one-way bearing is provided between the first bevel gear and the screw, and the second one-way bearing is provided between the second bevel gear and the screw; the first bevel gear and the second bevel gear are both engaged with the third bevel gear, and the third bevel gear is fixed on the rotating shaft of the generator; when the screw rotates forward, the first bevel gear rotates with the screw, and the second bevel gear remains stationary; when the screw rotates reversely, the first bevel gear remains stationary, and the second bevel gear rotates with the screw.

[0021] Optionally, it also includes a side-pressure telescopic rod; one end of the side-pressure telescopic rod is arranged on the frame, and the other end of the side-pressure telescopic rod abuts against the outer side wall of the second cylinder; the side-pressure telescopic rod is electrically connected to the processor.

[0022] Optionally, it also includes a battery and a rectifier; the generator, the rectifier and the battery are electrically connected in sequence; and the battery is electrically connected to the processor.

[0023] Optionally, the three-degree-of-freedom platform includes a mounting plate and three electric push rods; the mounting plate is arranged on the frame; one end of each electric push rod is rotatably connected to the mounting plate, and the other end of the electric push rod is rotatably connected to the workbench; the electric push rod is electrically connected to the processor.

[0024] Optionally, the workbench is provided with a connecting piece extending along the vibration direction of the vibration mechanism, the connecting piece is provided with a plurality of first mounting holes along the length direction of the connecting piece, the mounting frame is provided with a second mounting hole, and the bolt passes through the first mounting hole and the second mounting hole and is connected to the nut.

[0025] Optionally, the driving mechanism includes a driving motor, a support rod, a driving roller, a mounting tube and a driving spring; the driving roller is rotatably connected to the support rod, and the driving motor is arranged on the support rod and is transmission-connected to the driving roller; a limit block is provided on the outer side of the support rod, and the support rod is slidably sleeved in the mounting tube; the driving spring is sleeved on the outer side of the support rod, one end of the driving spring abuts against the limit block, and the other end of the driving spring abuts against the mounting tube; the mounting tube is fixed on the frame.

[0026] Optionally, the vibration mechanism includes a first rod, a second rod, a third rod, a rocker, a crank and a vibration motor;

[0027] One end of the first rod is rotatably connected to the frame, and the other end of the first rod is rotatably connected to the rocker; an end of the rocker away from the first rod is rotatably connected to the crank; the vibration motor is disposed on the frame and is used to drive the crank to rotate; one end of the second rod is rotatably connected to the middle portion of the first rod, and the other end of the second rod is rotatably connected to the third rod;

[0028] The frame is provided with a mounting seat, and the mounting seat is provided with a sliding hole extending in a vertical direction; the third rod is matched with the sliding hole, and the third rod is fixedly connected to the bearing platform.

[0029] The present invention proposes a shock absorber friction test device. A drive mechanism rotates the wheel on a supporting platform to simulate the wheel's state during driving. A vibration mechanism also causes the supporting platform to vibrate up and down, simulating the wheel's up-and-down motion on an uneven road surface. A three-degree-of-freedom platform can move the wheel along the X-axis, along the Y-axis, and rotate about the Z-axis to simulate wheel roll and side slip on the road. The drive mechanism, vibration mechanism, and three-degree-of-freedom platform effectively simulate the shock absorber's state under real-world operating conditions. Displacement sensors and force sensors are then used to record the shock absorber's excitation velocity and damping force, respectively, enabling analysis of the friction experienced by the shock absorber under real-world conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. 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 the structures shown in these drawings without paying any creative work.

[0031] Figure 1 This is a schematic structural diagram of a vibration damper friction force testing device according to an embodiment of the present invention;

[0032] Figure 2 This is a schematic structural diagram of a wheel and a drive mechanism according to an embodiment of the present invention;

[0033] Figure 3 Schematic diagram of the structure of the shock absorber according to an embodiment of the present invention.

[0034] Icons: 10, rack; 11, mounting base; 20, three-degree-of-freedom platform; 210, mounting plate; 220, electric push rod; 230, workbench; 240, connector; 2401, first mounting hole; 310, mounting bracket; 320, shock absorber; 3210, first cylinder; 3220, second cylinder; 3230, shock absorber spring; 3240, screw; 32510, first bevel gear; 32520, second bevel gear; 32530, third bevel gear; 3260, generator; 3270, housing; 3280, transmission shaft; 3290, coupling Axle; 330, swing arm assembly; 3310, upper swing arm; 3320, lower swing arm; 340, wheel; 350, displacement sensor; 360, force sensor; 410, drive motor; 420, support rod; 430, drive roller; 440, mounting cylinder; 450, drive spring; 510, load-bearing platform; 5110, first platform; 5120, second platform; 520, rotating roller; 610, first rod; 620, second rod; 630, third rod; 640, rocker; 650, crank; 660, vibration motor; 70, data collector. DETAILED DESCRIPTION

[0035] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0036] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0037] In the present invention, unless otherwise specified or limited, the terms "connection" and "fixation" should be understood in a broad sense. For example, "fixation" can mean fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two elements or interaction between two elements, unless otherwise specified. Those skilled in the art will be able to understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0038] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of such features. In addition, the meaning of "and / or" appearing throughout the text includes three parallel schemes. Taking "A and / or B" as an example, it includes scheme A, or scheme B, or a scheme in which A and B are satisfied at the same time. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0039] refer to Figure 1-Figure 3 A shock absorber friction test device comprises: a frame 10; a three-degree-of-freedom platform 20, one end of which is arranged on the frame 10 and the other end of which is provided with a workbench 230; the three-degree-of-freedom platform 20 is used to drive the workbench 230 to move along the X-axis, move along the Y-axis and rotate around the Z-axis; a suspension mechanism comprises a mounting frame 310, a shock absorber 320, a swing arm assembly 330 and a wheel 340; the mounting frame 310 is arranged on the workbench 230; one end of the swing arm assembly 330 is connected to the mounting frame 310, and the other end of the swing arm assembly 330 is rotatably connected to the wheel 340; one end of the shock absorber 320 is connected to the swing arm assembly 330, and the other end of the shock absorber 320 is connected to the mounting frame 310; There are a displacement sensor 350 and a force sensor 360; the displacement sensor 350 is used to detect the excitation speed of the shock absorber 320; the force sensor 360 is used to detect the damping force exerted on the shock absorber 320; a driving mechanism is arranged on the frame 10 and is used to drive the wheel 340 to rotate; a bearing assembly includes a bearing platform 510 and a plurality of rotating rollers 520 rotatably connected to the bearing platform 510; wherein the wheel 340 abuts the rotating rollers 520; a vibration mechanism, the vibration mechanism is arranged on the frame 10 and is used to drive the bearing platform 510 to vibrate up and down; a processor, the three-degree-of-freedom platform 20, the driving mechanism, the displacement sensor 350, the force sensor 360 and the vibration mechanism are all electrically connected to the processor.

[0040] The drive mechanism rotates the wheel 340 on the support platform 510 to simulate the state of the wheel 340 during driving. At this time, the vibration mechanism causes the support platform 510 to vibrate up and down to simulate the up and down movement of the wheel 340 on an uneven road surface. The three-degree-of-freedom platform 20 can move the wheel 340 along the X-axis, along the Y-axis, and rotate about the Z-axis to simulate the wheel 340 rolling and sliding on the road. The drive mechanism, vibration mechanism, and three-degree-of-freedom platform 20 effectively simulate the state of the shock absorber 320 in real-world operating conditions. By using the displacement sensor 350 and force sensor 360 to record the excitation velocity and damping force of the shock absorber 320, respectively, the friction force acting on the shock absorber 320 in real-world operating conditions can be analyzed.

[0041] The frame 10 may be a frame structure. When the frame 10 is placed on a horizontal ground, the vibration direction of the vibration mechanism is a vertical direction.

[0042] The upper end of the three-degree-of-freedom platform 20 can be fixed on the frame 10 , and the lower end of the three-degree-of-freedom platform 20 is connected to the mounting frame 310 .

[0043] The swing arm assembly 330 includes a lower swing arm 3320 and an upper swing arm 3310, while the wheel 340 includes a tire and a wheel hub. One end of the upper swing arm 3310 is rotatably connected to the wheel hub, while the other end is rotatably connected to the mounting bracket 310. One end of the lower swing arm 3320 is rotatably connected to the wheel hub, while the other end is rotatably connected to the mounting bracket 310. There are two upper and two lower swing arms 3310, respectively. A connecting rod is provided between the two lower swing arms 3320. One end of the shock absorber 320 is rotatably connected to the connecting rod, while the other end of the shock absorber 320 passes between the two upper swing arms 3310 and is rotatably connected to the mounting bracket 310.

[0044] The displacement sensor 350 may be disposed on the shock absorber 320. The force sensor 360 may be disposed at the end of the shock absorber 320 connected to the mounting bracket 310.

[0045] The shock absorber friction force testing device may further include a data collector 70, which is used to record data detected by the force sensor 360 and the displacement sensor 350. The data collector 70 may include a display and an operating platform both electrically connected to the processor.

[0046] The driving mechanism may be located on the side of the wheel 340 , and the driving mechanism contacts the outer side of the wheel 340 , and utilizes friction to drive the wheel 340 to rotate relative to the swing arm assembly 330 .

[0047] Multiple rotating rollers 520 are arranged radially along the wheel 340, with the axis of each roller 520 parallel to the axis of the wheel 340. When the wheel 340 remains stationary, it contacts one or more of the central rotating rollers 520. When the three-degree-of-freedom platform 20 drives the wheel 340 to simulate side slip or roll, the multiple rotating rollers 520 ensure that the wheel 340 remains in contact with the rotating rollers 520, preventing the wheel 340 from separating from the rotating rollers 520.

[0048] The rotating roller 520 is detachably connected to the supporting platform 510. The rotating roller 520 includes a roller body and connecting shafts at both ends of the roller body. The supporting platform 510 includes a first platform 5110 and a second platform 5120. The first platform 5110 is connected to the vibration mechanism and has a receiving groove for accommodating the roller body of the rotating roller 520 and a first retaining groove for engaging the connecting shaft. The receiving groove is connected to the first retaining groove. The second platform 5120 is shaped like a cover plate and has multiple rolling holes for exposing the roller body and second retaining grooves corresponding to the first retaining grooves. The second retaining grooves are also used to engage the connecting shaft. The first platform 5110 can be provided with threaded holes. The second platform 5120 can be placed on the first platform 5110 and bolts can be passed through the second platform 5120 and threadedly connected to the first platform 5110 to connect the first platform 5110 and the second platform 5120.

[0049] The rotating roller 520 can be made of various materials. In some embodiments, the roller body can be cast from concrete, while the connecting shaft is made from metal. In this case, the contact between the rotating roller 520 and the wheel 340 can simulate the wheel 340 running on a concrete surface. In other embodiments, the connecting shaft can be made from metal, and a metal mesh can be attached to the side of the connecting shaft. The maximum outer diameter of the metal mesh is smaller than the outer diameter of the roller body. In this case, asphalt is poured outside the connecting shaft, and the asphalt is in close contact with the metal mesh. The poured asphalt forms the roller body, and the contact between the rotating roller 520 and the wheel 340 simulates the wheel 340 running on an asphalt surface.

[0050] As an optional implementation, based on the excitation velocity and damping force of the shock absorber 320, the friction force of the shock absorber 320 is calculated using a friction force algorithm. The friction force algorithm is:

[0051] F p =f c sgn(v0)+c m v0;

[0052] Among them, F p represents the damping force, f c represents friction, c m represents the viscous term of mechanical damping, sgn represents a sign function, and v0 represents the excitation velocity of the shock absorber 320.

[0053] v0 = 2πfs0cos(2πft);

[0054] Wherein, f represents the excitation frequency, s0 represents the excitation amplitude, and t represents time. The excitation frequency and the excitation amplitude can be detected by the displacement sensor 350 , and then the excitation speed of the shock absorber 320 can be further calculated.

[0055] In this embodiment, the vibration absorber 320 is a regenerative vibration absorber. The damping force reflects the internal friction losses of the vibration absorber, which mainly include friction within the screw 3240, the bevel gear pair (including the first bevel gear 32510, the second bevel gear 32520, and the third bevel gear 32530), and the generator 3260, as well as windage and magnetic losses within the generator 3260.

[0056] As an optional embodiment, the shock absorber 320 includes a first cylinder 3210, a second cylinder 3220, a shock absorbing spring 3230, a screw 3240, a transmission unit and a generator 3260;

[0057] One end of the first cylinder 3210 is connected to the mounting bracket 310, and the other end of the first cylinder 3210 is slidably sleeved within the second cylinder 3220. A positioning block is provided on the outside of the second cylinder 3220. The end of the second cylinder 3220 away from the first cylinder 3210 is connected to the swing arm assembly 330. The damping spring 3230 is sleeved on the outside of the first cylinder 3210, with one end of the damping spring 3230 abutting against the first cylinder 3210 and the other end of the damping spring 3230 abutting against the positioning block.

[0058] One end of the screw 3240 extends into the first cylinder 3210 and is threadedly connected to the first cylinder 3210, and the other end of the screw 3240 is in transmission connection with the transmission unit; the transmission unit is used to convert the forward rotation and reverse rotation of the screw 3240 into the forward rotation of the rotating shaft of the generator 3260, and the forward rotation state of the generator 3260 is the power generation state.

[0059] In this embodiment, when the vibration mechanism drives the wheel 340 upward, the second cylinder 3220 compresses the damping spring 3230 upward, and the second cylinder 3220 drives the screw 3240 upward. At this time, the first cylinder 3210 is relatively stationary. Because the screw 3240 is threadedly connected to the first cylinder 3210, the linear motion of the screw 3240 is converted into rotational motion, and the screw 3240 rotates in the forward direction. When the vibration mechanism moves downward, the damping spring 3230 returns to its original length and drives the second cylinder 3220 downward, and the screw 3240 rotates in the reverse direction. Regardless of whether the screw 3240 rotates forward or reverse, the transmission unit transmits the rotational motion of the screw 3240 to the generator 3260, causing the generator 3260 to rotate and generate electricity.

[0060] The shock absorber friction force test device also includes a battery and a rectifier. The generator 3260, the rectifier, and the battery are electrically connected in sequence, and the battery is electrically connected to the processor. Some of the energy lost by the shock absorber 320 can be converted into electrical energy by the generator 3260, which is ultimately stored in the battery. The electrical energy in the battery can be used to power the displacement sensor 350 and the force sensor 360. In some embodiments, a vehicle can utilize the shock absorber of this embodiment, and the electrical energy generated by the shock absorber 320 and the generator 3260 can be used to power the vehicle's electronic devices, such as sensors.

[0061] The screw 3240 may be a ball screw, and a ball is included in the matching structure between the screw 3240 and the first cylinder 3210 .

[0062] As an optional embodiment, the transmission unit includes a first bevel gear 32510, a second bevel gear 32520, a third bevel gear 32530, a first one-way bearing and a second one-way bearing;

[0063] A shell 3270 is provided at the end of the second cylinder 3220 away from the first cylinder 3210, and the transmission unit is located in the inner cavity of the shell 3270; the first bevel gear 32510 and the second bevel gear 32520 are both connected to the screw 3240 for transmission, and a first one-way bearing is provided between the first bevel gear 32510 and the screw 3240, and a second one-way bearing is provided between the second bevel gear 32520 and the screw 3240; the first bevel gear 32510 and the second bevel gear 32520 are both engaged with the third bevel gear 32530, and the third bevel gear 32530 is fixed on the rotating shaft of the generator 3260.

[0064] In this embodiment, when the screw 3240 rotates in the forward direction, the first bevel gear 32510 rotates with the screw 3240, while the second bevel gear 32520 remains stationary. When the screw 3240 rotates in the reverse direction, the first bevel gear 32510 remains stationary, while the second bevel gear 32520 rotates with the screw 3240. Because the third bevel gear 32530 is engaged with both the first bevel gear 32510 and the second bevel gear 32520, when the first bevel gear 32510 drives the third bevel gear 32530 to rotate, the third bevel gear 32530 rotates in the forward direction. At this time, the generator 3260 generates electricity, and the second bevel gear 32520 can also drive the third bevel gear 32530 to rotate in the forward direction.

[0065] In some embodiments, the third bevel gear 32530 can be fixed on the transmission shaft 3280 , and the transmission shaft 3280 is connected to the rotating shaft of the generator 3260 through a coupling 3290 .

[0066] As an optional embodiment, it also includes a side pressure telescopic rod; one end of the side pressure telescopic rod is set on the frame 10, and the other end of the side pressure telescopic rod abuts against the outer wall of the second cylinder 3220; the side pressure telescopic rod is electrically connected to the processor.

[0067] In this embodiment, the lateral pressure telescopic rod can be an electric push rod, and a curved rubber pad can be provided on the end of the lateral pressure telescopic rod that abuts the second cylinder 3220. The lateral pressure telescopic rod applies a lateral force to the shock absorber 320. The displacement sensor 350 and force sensor 360 detect the excitation velocity and damping force of the shock absorber 320 to analyze the effect of the lateral force on the friction of the shock absorber 320.

[0068] As an optional embodiment, the three-degree-of-freedom platform 20 includes a mounting plate 210 and three electric push rods 220; the mounting plate 210 is set on the frame 10; one end of each electric push rod 220 is rotatably connected to the mounting plate 210, and the other end of the electric push rod 220 is rotatably connected to the workbench 230; the electric push rod 220 is electrically connected to the processor.

[0069] In this embodiment, three electric push rods 220 are arranged on the mounting plate 210 at intervals of 120°. By controlling the extension of the three electric push rods 220 to different lengths, the workbench 230 can be driven to move along the X-axis, along the Y-axis, and rotate about the Z-axis. For example, if two electric push rods 220 are extended by a and one electric push rod 220 is extended by b, when a and b reach certain specific values, the workbench 230 can be moved horizontally. The specific values of a and b can be measured experimentally.

[0070] As an optional embodiment, the workbench 230 is provided with a connecting member 240 extending along the vibration direction of the vibration mechanism, the connecting member 240 is provided with a plurality of first mounting holes 2401 along the length direction of the connecting member 240, the mounting frame 310 is provided with a second mounting hole, and the bolt passes through the first mounting hole 2401 and the second mounting hole and is connected to the nut.

[0071] In this embodiment, the distance between the center of wheel 340 and support platform 510 can be adjusted by aligning the second mounting holes with first mounting holes 2401 at different locations and then securing mounting bracket 310 to connector 240 using bolts and nuts. When shock absorbers on different vehicles are tested, the diameter of wheel 340 and the dimensions of swing arm assembly 330 may vary. In this case, mounting bracket 310 can be secured to different locations on connector 240 to ensure that wheel 340 contacts support platform 510.

[0072] As an optional embodiment, the driving mechanism includes a driving motor 410, a support rod 420, a driving roller 430, a mounting tube 440 and a driving spring 450; the driving roller 430 is rotatably connected to the support rod 420, and the driving motor 410 is arranged on the support rod 420 and is transmission-connected to the driving roller 430; a limit block is provided on the outside of the support rod 420, and the support rod 420 is slidably sleeved in the mounting tube 440; the driving spring 450 is sleeved on the outside of the support rod 420, one end of the driving spring 450 abuts against the limit block, and the other end of the driving spring 450 abuts against the mounting tube 440; the mounting tube 440 is fixed on the frame 10.

[0073] In this embodiment, the drive motor 410 rotates the drive roller 430. The outer surface of the drive roller 430 may be made of a rubber material. The drive roller 430 drives the wheel 340 to rotate through friction. When the drive roller 430 contacts the surface of the wheel 340, a certain pressure exists between the drive roller 430 and the wheel 340. At this time, the drive roller 430 drives the support rod 420 to slide along the mounting tube 440, and the drive spring 450 is compressed. When the vibration mechanism drives the wheel 340 to vibrate up and down, the contact point between the drive roller 430 and the wheel 340 changes. The presence of the drive spring 450 ensures that the support rod 420 can always drive the drive roller 430 to contact the surface of the wheel 340.

[0074] As an optional embodiment, the vibration mechanism includes a first rod 610, a second rod 620, a third rod 630, a rocker 640, a crank 650 and a vibration motor 660;

[0075] One end of the first rod 610 is rotatably connected to the frame 10, and the other end of the first rod 610 is rotatably connected to the rocker 640; the end of the rocker 640 away from the first rod 610 is rotatably connected to the crank 650; a vibration motor 660 is disposed on the frame 10 and is used to drive the crank 650 to rotate; one end of the second rod 620 is rotatably connected to the middle portion of the first rod 610, and the other end of the second rod 620 is rotatably connected to the third rod 630;

[0076] The frame 10 is provided with a mounting seat 11 , and the mounting seat 11 is provided with a sliding hole extending in a vertical direction; the third rod 630 is matched with the sliding hole, and the third rod 630 is fixedly connected to the carrying platform 510 .

[0077] In this embodiment, the first rod 610, the rocking arm 640, and the crank 650 form a crank 650-rocker 640 mechanism. The vibration motor 660 drives the crank 650 to rotate. The crank 650, through the rocking arm 640, then drives the first rod 610 to swing relative to the frame 10. The first rod 610, through the second rod 620, then drives the third rod 630 to move up and down. The sliding hole limits the third rod 630. The vibration frequency of the vibration mechanism is related to the rotation speed of the vibration motor 660, and the amplitude of the vibration mechanism is related to the length of the first rod 610, the crank 650, and the rocking arm 640.

[0078] In some embodiments, the first rod 610 may be an electric push rod. In this case, the first rod 610 is electrically connected to the processor, and the amplitude of the vibration mechanism can be changed by controlling the extension or contraction of the first rod 610, which is simple to operate.

[0079] The above descriptions are merely optional embodiments of the present invention and do not limit the patent scope of the present invention. All equivalent structural transformations made using the contents of the present description and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included in the patent protection scope of the present invention.

Claims

1. A vibration damper friction test device, characterized in that: include: frame; A three-degree-of-freedom platform, one end of which is arranged on the frame and the other end of which is provided with a workbench; The three-degree-of-freedom platform is used to drive the workbench to move along the X-axis, move along the Y-axis, and rotate around the Z-axis; The suspension mechanism includes a mounting frame, a shock absorber, a swing arm assembly, and a wheel; the mounting frame is disposed on the workbench; one end of the swing arm assembly is connected to the mounting frame, and the other end of the swing arm assembly is rotatably connected to the wheel; one end of the shock absorber is connected to the swing arm assembly, and the other end of the shock absorber is connected to the mounting frame; a displacement sensor and a force sensor are provided on the shock absorber; the displacement sensor is used to detect the excitation velocity of the shock absorber; and the force sensor is used to detect the damping force applied to the shock absorber; a driving mechanism, disposed on the frame and used to drive the wheel to rotate; The bearing assembly comprises a bearing platform and a plurality of rotating rollers rotatably connected to the bearing platform; wherein the wheels abut against the rotating rollers; a vibration mechanism, the vibration mechanism being arranged on the frame and being used to drive the carrying platform to vibrate up and down; a processor, the three-degree-of-freedom platform, the drive mechanism, the displacement sensor, the force sensor, and the device vibration mechanism being electrically connected to the processor; Based on the excitation velocity and damping force of the shock absorber, the friction force of the shock absorber is calculated using a friction force algorithm, which is: F p =f c sgn(v0)+c m v0; Among them, F p represents the damping force, f c represents friction, c m represents the viscous term of mechanical damping, sgn represents the sign function, and v0 represents the excitation velocity of the shock absorber.

2. The shock absorber friction force testing device according to claim 1, characterized in that: The vibration absorber includes a first cylinder, a second cylinder, a vibration damping spring, a screw, a transmission unit and a generator; One end of the first cylinder is connected to the mounting bracket, and the other end of the first cylinder is slidably sleeved in the second cylinder; a positioning block is provided on the outside of the second cylinder; an end of the second cylinder away from the first cylinder is connected to the swing arm assembly; the vibration damping spring is sleeved on the outside of the first cylinder, one end of the vibration damping spring abuts against the first cylinder, and the other end of the vibration damping spring abuts against the positioning block; One end of the screw extends into the first cylinder and is threadedly connected to the first cylinder, and the other end of the screw is in transmission connection with the transmission unit; the transmission unit is used to convert the forward and reverse rotation of the screw into the forward rotation of the generator shaft, and the forward rotation state of the generator is the power generation state.

3. The shock absorber friction force testing device according to claim 2, characterized in that: The transmission unit includes a first bevel gear, a second bevel gear, a third bevel gear, a first one-way bearing and a second one-way bearing; A shell is provided at one end of the second cylinder away from the first cylinder, and the transmission unit is located in the inner cavity of the shell; the first bevel gear and the second bevel gear are both connected to the screw for transmission, and the first one-way bearing is provided between the first bevel gear and the screw, and the second one-way bearing is provided between the second bevel gear and the screw; the first bevel gear and the second bevel gear are both engaged with the third bevel gear, and the third bevel gear is fixed on the rotating shaft of the generator; when the screw rotates forward, the first bevel gear rotates with the screw, and the second bevel gear remains stationary; when the screw rotates reversely, the first bevel gear remains stationary, and the second bevel gear rotates with the screw.

4. The shock absorber friction force testing device according to claim 2, characterized in that: It also includes a side-pressure telescopic rod; one end of the side-pressure telescopic rod is arranged on the frame, and the other end of the side-pressure telescopic rod abuts against the outer side wall of the second cylinder; the side-pressure telescopic rod is electrically connected to the processor.

5. The shock absorber friction force testing device according to claim 2, characterized in that: It also includes a battery and a rectifier; the generator, the rectifier and the battery are electrically connected in sequence; and the battery is electrically connected to the processor.

6. The shock absorber friction force testing device according to claim 1, characterized in that: The three-degree-of-freedom platform includes a mounting plate and three electric push rods; the mounting plate is arranged on the frame; one end of each electric push rod is rotatably connected to the mounting plate, and the other end of the electric push rod is rotatably connected to the workbench; the electric push rod is electrically connected to the processor.

7. The shock absorber friction force testing device according to claim 1, characterized in that: The workbench is provided with a connecting piece extending along the vibration direction of the vibration mechanism, the connecting piece is provided with a plurality of first mounting holes along the length direction of the connecting piece, the mounting frame is provided with a second mounting hole, and the bolt passes through the first mounting hole and the second mounting hole and is connected with a nut.

8. The shock absorber friction force testing device according to claim 1, characterized in that: The driving mechanism includes a driving motor, a support rod, a driving roller, a mounting tube and a driving spring; the driving roller is rotatably connected to the support rod, and the driving motor is arranged on the support rod and is transmission-connected to the driving roller; a limit block is provided on the outer side of the support rod, and the support rod is slidably sleeved in the mounting tube; the driving spring is sleeved on the outer side of the support rod, one end of the driving spring abuts against the limit block, and the other end of the driving spring abuts against the mounting tube; the mounting tube is fixed to the frame.

9. The shock absorber friction force testing device according to claim 1, characterized in that: The vibration mechanism includes a first rod, a second rod, a third rod, a rocker, a crank and a vibration motor; One end of the first rod is rotatably connected to the frame, and the other end of the first rod is rotatably connected to the rocker; an end of the rocker away from the first rod is rotatably connected to the crank; the vibration motor is disposed on the frame and is used to drive the crank to rotate; one end of the second rod is rotatably connected to the middle portion of the first rod, and the other end of the second rod is rotatably connected to the third rod; The frame is provided with a mounting seat, and the mounting seat is provided with a sliding hole extending in a vertical direction; the third rod is matched with the sliding hole, and the third rod is fixedly connected to the bearing platform.

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