Compact reciprocating type multi-working-condition pin disc friction experiment device and method

Abstract

The invention belongs to the technical field of tribology testing, and particularly relates to a compact reciprocating type multi-working-condition pin disc friction experiment device and method.The compact reciprocating type multi-working-condition pin disc friction experiment device comprises a rack, a compact transmission mechanism, a driving motor, a linkage mechanism, a pin clamping and loading device and a friction disc assembly; the compact transmission mechanism comprises a transmission shaft I, a transmission shaft mounting seat I, a transmission shaft mounting seat II, and a transmission shaft II, a universal joint I, a transmission square rod, a universal joint II and a motor coupling which are connected in sequence; a driving motor is connected with a motor coupling, a transmission shaft I is mounted in the transmission shaft mounting seat I, and a transmission shaft II is mounted in the transmission shaft mounting seat II; the friction disc assembly comprises a mounting plate and a friction disc mounted on the mounting plate; the linkage mechanism comprises a connecting shaft, a rotating arm, a guide rod and a guide rod frame fixed to the machine frame. The problems that an existing reciprocating type pin disc friction experiment device is large in size, high in space occupancy rate, low in integration level and incapable of guaranteeing long-time test measurement precision are solved.

Description

TECHNICAL FIELD

[0001] The application relates to a compact reciprocating multi-working-condition pin-on-disc friction test device and method, and belongs to the technical field of tribology testing. BACKGROUND

[0002] Tribological testing is an integral part of material science and mechanical engineering, which is used to evaluate the friction coefficient and wear performance of materials under actual working conditions. Among various types of friction testers, reciprocating pin-on-disc friction testers are widely used because their motion mode is highly similar to the sliding contact of many actual mechanical components (such as pistons, bearings, gears, etc.).

[0003] The closest prior art to the present application on the market usually adopts the following technical measures and / or product composition: 1. Structure: The existing reciprocating friction testers usually adopt a "separated" or "benchtop" design. The main frame is used to carry the driving and loading mechanisms; the driving system (such as a crank connecting rod or a linear motor) is large in size and is arranged vertically or horizontally independently; the loading mechanism (such as a pneumatic or weight loading) is relatively independent of the sensor system. 2. Functional characteristics: They usually have basic reciprocating frequency, load control and friction torque measurement functions, and some high-end devices can be equipped with high-temperature or medium immersion accessories to realize multi-working-condition testing. 3. Motion and measurement: The motion components and force sensors are connected through complex transmission or connecting parts, forming a long force transmission chain.

[0004] Problems and shortcomings of the prior art: 1. Large equipment size, low space utilization: Due to the dispersed and modular design of the driving motor, loading system and main measurement structure, the entire device occupies a large amount of experimental bench space. In modern laboratories, there is an increasing demand for compactness and integration of equipment, and the size of existing equipment limits its application in small laboratories or vehicle-mounted mobile testing platforms.

[0005] 2. Significant decline in measurement accuracy over a long period of use: Since sample wear is essential in friction testing, it is a difficult problem to ensure maximum accuracy over a long period of testing. The existing testers do not have an effective solution.

[0006] 3. Complex multi-working-condition switching and operation: The existing devices often require users to manually install and remove large auxiliary accessories to achieve multi-working-condition testing, which is complex, time-consuming and difficult to achieve rapid and seamless switching of test conditions. SUMMARY

[0007] The present application aims at the problems existing in the prior art, and provides a compact reciprocating multi-working-condition pin-disk friction experiment device and method.

[0008] The technical scheme provided by the present application to solve the above technical problems is: a compact reciprocating multi-working-condition pin-disk friction experiment device, comprising a rack, a compact transmission mechanism, a driving motor, a linkage mechanism, a pin clamping and loading device, and a friction disc assembly. The compact transmission mechanism comprises a transmission shaft I, a transmission shaft mounting seat I, a transmission shaft mounting seat II, and a transmission shaft II, a universal joint I, a transmission square rod, a universal joint II, and a motor shaft coupling connected in sequence; the driving motor is connected with the motor shaft coupling; the transmission shaft I is mounted in the transmission shaft mounting seat I; the transmission shaft II is mounted in the transmission shaft mounting seat II; the transmission shaft mounting seat I and the transmission shaft mounting seat II are both fixed on the rack; the transmission shaft I is provided with a rotary disc and a large bevel gear at both ends thereof; and the transmission shaft II is provided with a small bevel gear meshing with the large bevel gear at one end thereof. The friction disc assembly comprises a mounting plate and a friction disc mounted on the mounting plate; and the mounting plate is slidingly mounted on the rack. The linkage mechanism comprises a connecting shaft, a rotary arm, a guide rod, and a guide rod holder fixed on the rack; the guide rod is slidingly mounted on the guide rod holder; one end of the connecting shaft is fixed on the rotary disc, and the other end thereof is rotatably mounted on one end of the rotary arm; and both ends of the guide rod are hingedly connected with the mounting plate and the rotary arm respectively. The pin clamping and loading device is mounted on the rack and located above the friction disc.

[0009] Further, the pin clamping and loading device comprises a clamping table, a universal joint, a pin clamp, a cylinder fixing frame, and a cylinder; the cylinder fixing frame is mounted on the clamping table; the cylinder is vertically fixed on the cylinder fixing frame; and both upper and lower ends of the universal joint are connected with a piston rod of the cylinder and an upper end of the pin clamp respectively.

[0010] Further, the pin clamp comprises a clamp shell and a fixed cylinder fixed at a lower end of the clamp shell; a fixed block and a fixed bolt are arranged in the fixed cylinder; and an upper end of the clamp shell is connected with the universal joint.

[0011] Further, a first force sensor is arranged between the upper end of the clamp shell and the universal joint; and a second force sensor is arranged between the rotary arm and the guide rod.

[0012] Further technical solutions are that the rack is provided with a liquid injection system, the liquid injection system comprises a liquid tank, a liquid hose, a water pump and a metal pipe connected in sequence and communicated, and the liquid tank and the water pump are fixed on the rack and the clamping table respectively.

[0013] Further technical solutions are that the rack is provided with an air cooling system, the air cooling system comprises a bracket mounted on the rack, and the bracket is provided with a fan and an air duct.

[0014] Further technical solutions are that the rack is provided with a gear protection shell for protecting the large bevel gear and the small bevel gear.

[0015] Further technical solutions are that the friction disc is installed on the mounting plate through a fixing screw.

[0016] Further technical solutions are that the bottom of the rack is provided with a plurality of supporting feet.

[0017] A compact reciprocating multi-working-condition pin-disc friction experiment method, specifically comprising the following steps: Step one, select the required friction disc and pin sample, install the friction disc on the mounting plate, and fix the pin sample on the fixed block through the fixing bolt; Step two, start the air cylinder, lower the pin sample to the upper surface of the friction disc, record the data through the first force sensor, obtain the real-time normal load, and adjust the output air pressure of the air cylinder through the down pressure closed loop control method, so that the real-time normal load reaches the set value; Step three, start the driving motor to drive the friction disc to reciprocate, and record the data through the second force sensor; Step four, process the data recorded by the second force sensor to obtain the real-time effective friction force; Step five, determine the instantaneous friction coefficient according to the real-time normal load and the real-time effective friction force, and output the friction coefficient related curve.

[0018] Further technical solutions are that the specific steps of the down pressure closed loop control method in step two are as follows: Step 1, set the target pressure spectrum according to the experimental requirements; Step 2, the controller generates a target signal according to the target pressure spectrum; Step 3, read the first force sensor signal and calculate the deviation between the first force sensor signal and the target signal, if the deviation is greater than the threshold deviation, the controller outputs an adjustment signal; Step 4, control the electric control valve on the gas cylinder to adjust the output air pressure according to the adjustment signal; Step 5, repeat steps 3-4 until the deviation is less than or equal to the threshold deviation, then end the control.

[0019] The beneficial effects of the present application are as follows: 1. Good compactness and operation efficiency can be realized, and it is more suitable for laboratories with limited space or as desktop research equipment. This reduces the threshold and cost of equipment placement.

[0020] 2. Convenient operation and maintenance, the design of the disc groove and its guide rail will ensure the quick positioning and replacement of the test piece (disc). At the same time, the modular integration (such as air cooling and liquid system) allows the operator to quickly switch the experimental conditions, improving the turnover efficiency of the experiment.

[0021] 3. Application and research value. It can quickly and efficiently test the friction and wear properties of different materials (metal, ceramic, polymer, etc.) under reciprocating motion mode, accelerating the research and development and screening of new materials; it can be used to optimize the lubricant formula, load parameters and motion frequency of specific parts (such as piston rings, bearings, gears, etc.) under reciprocating sliding conditions. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 is a three-dimensional schematic view of the present application; Figure 2 is a front view of the present application; Figure 3 is a top view of the present application; Figure 4 is a left view of the present application; Figure 5 is a right view of the present application; Figure 6 is a structural schematic view of the rotating disc; Figure 7 is a structural schematic view of the pin clamping and loading device; Figure 8 is a structural schematic view of the pin clamp; Figure 9 is a structural schematic view of the fixed block; Figure 10 is a structural schematic view of the liquid injection system; Figure 11 is a structural schematic view of the air cooling system; Figure 12 is a structural schematic view of the gear protection shell; Figure 13 is a structural schematic view of the sandbox; Figure 14 is a flowchart of the present application.

[0023] The figure mark: 1-drive motor, 2-motor coupling, 3-gimbal II, 4-transmission square pole, 5-gimbal I, 6-transmission shaft mounting seat II, 7-protection shell, 8-mounting plate, 9-friction disc, 10-pinch loading device, 101-clamping table, 102-cylinder fixing frame, 103-cylinder, 104-clamp shell, 105-fixed cylinder, 106-fixed block, 107-fixed bolt, 11-air cooling system, 111-bracket, 112-fan, 113-air duct, 12-guide rod, 13-guide rod frame, 14-second force sensor, 15-rack, 16-rotating arm, 17-connecting shaft, 18-transmission shaft I, 19-rotating disc, 20-supporting leg, 21-transmission shaft mounting seat I, 22-transmission shaft II, 23-small bevel gear, 24-large bevel gear, 25-liquid tank, 26-liquid hose, 27-water pump, 28-metal pipe, 29-sand tank. DETAILED DESCRIPTION

[0024] The technical solutions of the present application will be described clearly and completely below in conjunction with the drawings. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work belong to the scope of protection of the present application.

[0025] In the description of the present application, it should be noted that the orientations or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second", "third" are only for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0026] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected. For those skilled in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.

[0027] In addition, the technical features involved in the different embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0028] As Figures 1-5As shown, a compact reciprocating multi-working condition pin disc friction experimental device and method of the present application comprises a rack 15, a compact transmission mechanism, a driving motor 1, a linkage mechanism, a pin clamping loading device 10 and a friction disc assembly. The compact transmission mechanism comprises a transmission shaft I 18, a transmission shaft mounting seat I 21, a transmission shaft mounting seat II 6 and sequentially connected transmission shaft II 22, universal joint I 5, transmission square rod 4, universal joint II 3 and motor coupling 2; the output shaft of the driving motor 1 is connected with the motor coupling 2; the transmission shaft I 18 is mounted in the transmission shaft mounting seat I 21; the transmission shaft II 22 is mounted in the transmission shaft mounting seat II 6; the transmission shaft mounting seat I 21 and the transmission shaft mounting seat II 6 are both fixed on the rack 15; the transmission shaft I 18 is provided with a turntable 19 and a large bevel gear 24 at both ends; the transmission shaft II 22 is provided with a small bevel gear 23 at one end which is engaged with the large bevel gear 24. The friction disc assembly comprises a mounting plate 8 and a friction disc 9 mounted on the mounting plate 8 by screws; the mounting plate 8 is slidingly mounted on the slide rail of the rack 15. The linkage mechanism comprises a connecting shaft 17, a rotating arm 16, a guide rod 12 and a guide rod holder 13 fixed on the rack 15; the guide rod 12 is slidingly mounted in the guide rod holder 13; one end of the connecting shaft 17 is fixed on the turntable 19 and the other end is rotatably mounted on one end of the rotating arm; the guide rod is hingedly connected with the mounting plate and the rotating arm at both ends. A specific structure of the turntable 19 is shown in Figure 6 As shown, the turntable 19 is provided with positioning holes at different positions at both sides; the connecting shaft 17 changes the connection position on the turntable 19, so as to realize multi-gear accurate conversion and adjustment of the reciprocating stroke. The pin clamping loading device 10 is mounted on the rack 15 and located above the friction disc 9; the pin sample is pressed on the friction disc 9 by clamping and loading of the pin clamping loading device 10; when the friction disc 9 reciprocates, the friction disc 9 rubs with the pin sample.

[0029] In this embodiment, as shown in Figure 7 A specific implementation structure of the pin clamping loading device 10 comprises a clamping table 101, a pin clamp, a universal joint, a cylinder fixing frame 102 and a cylinder 103; the cylinder fixing frame 102 is mounted on the clamping table 101; the cylinder 103 is vertically fixed on the cylinder fixing frame 102; the universal joint is connected with the piston rod of the cylinder 103; the upper end of the pin clamp is connected with the universal joint and the lower end is located above the friction disc 9.

[0030] As shown in Figure 8As shown, the pin fixture comprises a fixture housing 104 and a fixed cylinder 105 fixed at the lower end of the fixture housing 104, and the fixed cylinder 105 is provided with a fixed block 106 (structure as Figure 9 shown) and a fixed bolt 107, and the upper end of the fixture housing 104 is connected with the universal joint. The fixture housing 104 passes through the clamping table 101, and in order to avoid the rotation of the fixture housing 104, the fixture housing 104 is prismatic, and the clamping table 101 is provided with a groove matched therewith.

[0031] The structure of the fixed block 106 is as Figure 9 shown, the fixed block 106 is fixed on the inner wall of the fixed cylinder 105 by a bolt, then the pin sample is placed between the fixed block 106 and the fixed bolt 107, and then the fixed bolt 107 is rotated to press the pin sample on the fixed block 106, that is, the fixing process of the pin sample in the fixed cylinder 105 is completed.

[0032] In this embodiment, a first force sensor 108 is arranged between the upper end of the fixture housing and the universal joint; a second force sensor 14 is arranged between the rotating arm 16 and the guide rod 12; the first force sensor 108 is used to measure the normal load, and the second force sensor 14 is used to measure the friction force, that is, the friction coefficient is calculated through the above two data.

[0033] In this embodiment, as Figure 1 and Figure 10 shown, in order to facilitate the injection of various liquids in the experiment, the preferred embodiment is that the rack 15 is provided with a liquid injection system, and the liquid injection system comprises a liquid tank 25, a liquid hose 26, a water pump 27 and a metal pipe 28 connected in sequence, the liquid tank 25 and the water pump 27 are fixed on the rack 15 and the clamping table 101 respectively, and the end of the metal pipe 28 is opposite to the contact position of the friction disc 9 and the pin sample, so that the experimental liquid can be sprayed on the pin sample by directly starting the water pump 27.

[0034] The liquid tank 25 in the system can be used in combination with a liquid storage tank. The liquid storage tank can be filled with cooling liquid, lubricating oil and other liquids, so that different experimental liquid requirements under different working conditions can be met by quickly replacing the liquid storage tank.

[0035] In this embodiment, as Figure 1 and Figure 11As shown, the problem of too high temperature of the friction surface of the pin disc during the experiment is solved, and preferably, the rack 15 is provided with a forced air cooling system 11, the forced air cooling system 11 comprises a support 111 mounted on the rack 15, the support 111 is provided with a fan 112 and an air duct 113, the air inlet of the air duct 113 is connected with the air outlet of the fan 112, and the air outlet of the air duct 113 is opposite to the contact position of the friction disc 9 and the pin sample, so that the fan 112 can blow air to cool the pin disc friction surface sample, and the worn particles can be blown away during long time experiment, so as to ensure that the contact of the pin disc friction surface is not affected by the worn particles during long time experiment.

[0036] In this embodiment, as shown in Figure 1 The rack 15 is provided with a gear protection shell 7 for protecting the bevel gear 24 and the pinion 23, and the specific structure of the gear protection shell 7 is as shown in Figure 12 The gear protection shell 7 specifically comprises an upper shell and a lower shell, the lower shell is fixed with the rack table top, and the upper shell is fixed with the lower shell, so as to prevent dust from entering the gear and prolong the service life of the testing machine; during daily maintenance, the upper shell can be disassembled for maintenance.

[0037] In this embodiment, as shown in Figure 1 The bottom of the rack 15 is provided with a plurality of supporting feet 20.

[0038] In this embodiment, as shown in Figure 1 Since there is a large inertia in the reciprocating motion, preferably, the rack 15 is provided with a sand box 29, and large particle sand is placed in the sand box 29 to reduce the inertia and avoid affecting the experimental results.

[0039] As shown in Figure 14 A compact reciprocating multi-working-condition pin-disc friction experiment method, specifically comprising the following steps: Step one, selecting the friction disc 9 and the pin sample required for the experiment, and installing the friction disc 9 on the mounting plate 8, and fixing the pin sample on the fixed block 106 through the fixing bolt 107; Step two, starting the air cylinder 103, lowering the pin sample to the upper surface of the friction disc 9, and recording the data F x (t) through the first force sensor 108, wherein t represents the time variable, that is, it is a dynamic real-time process; obtaining the real-time normal load; obtaining the real-time normal load, and adjusting the output air pressure of the air cylinder through the down pressure closed loop control method, so that the real-time normal load reaches the set value; As shown in Figure 14 The specific steps of the pressure closed loop control method are as follows: Step 1, setting the target pressure spectrum according to the experimental requirements; Step 2, the controller generates a target signal according to the target pressure spectrum; Step 3, read the first force sensor signal, and calculate the deviation of the first force sensor signal and the target signal, if the deviation is greater than the threshold deviation, the controller outputs an adjustment signal; Step 4, control the electric control valve on the gas cylinder to adjust the output gas pressure according to the adjustment signal; Step 5, repeat steps 3-4 until the deviation is less than or equal to the threshold deviation, then end the control.

[0040] Step three, start the drive motor 1, drive the friction disc 9 to reciprocate, and record the data F t (t) through the second force sensor 14; Step four, process the data F t (t) recorded by the second force sensor 14 to obtain the real-time friction force; Wherein F t (t) contains components for overcoming static friction (when the speed direction changes) and dynamic friction (in the uniform speed stage), that is, by processing the F t (t) signal through the data processor, identifying the stage representing stable dynamic friction in the reciprocating motion cycle, and extracting the effective value in this stage as the real-time friction force; Step five, determine the real-time friction coefficient according to the real-time normal load and the real-time friction force, that is, normal load / friction force=friction coefficient; wherein the relationship curve of the friction coefficient and the experimental time can be drawn according to the data of a time period.

[0041] The above description is not any form of limitation on the present application, although the present application has been disclosed by the above examples, however, it is not used to limit the present application, any skilled person in the art, without departing from the technical solution range of the present application, can make some changes or modifications for equivalent examples with the above disclosed technical content, as long as it does not deviate from the technical solution of the present application, according to the technical essence of the present application, any simple modification, equivalent change and modification of the above examples, all belong to the range of the technical solution of the present application.

Claims

1. A compact reciprocating multi-condition pin-on-disc friction test device, characterized in that, It includes a frame, a compact transmission mechanism, a drive motor, a linkage mechanism, a pin-clamping loading device, and a friction disc assembly; The compact transmission mechanism includes a drive shaft I, a drive shaft mounting seat I, a drive shaft mounting seat II, and a drive shaft II, a universal joint I, a drive square rod, a universal joint II, and a motor coupling connected in sequence. The drive motor is connected to the motor coupling. The drive shaft I is installed in the drive shaft mounting seat I, and the drive shaft II is installed in the drive shaft mounting seat II. Both the drive shaft mounting seat I and the drive shaft mounting seat II are fixed on the frame. The drive shaft I has a turntable and a large bevel gear at each end, and the drive shaft II has a small bevel gear at one end that meshes with the large bevel gear. The friction disc assembly includes a mounting plate and a friction disc mounted on the mounting plate, the mounting plate being slidably mounted on the frame; The linkage mechanism includes a connecting shaft, a rotating arm, a guide rod, and a guide rod frame fixed on the frame. The guide rod is slidably mounted on the guide rod frame. One end of the connecting shaft is fixed on the turntable, and the other end is rotatably mounted on one end of the rotating arm. The two ends of the guide rod are respectively hinged to the mounting plate and the rotating arm. The pin clamping loading device is mounted on the frame and located above the friction disc.

2. The compact reciprocating multi-condition pin-on-disc tribometer of claim 1, wherein, The pin clamping loading device includes a clamping platform, a universal joint, a pin clamp, a cylinder fixing frame, and a cylinder; the cylinder fixing frame is installed on the clamping platform, the cylinder is vertically fixed on the cylinder fixing frame, and the upper and lower ends of the universal joint are respectively connected to the piston rod of the cylinder and the upper end of the pin clamp.

3. The compact reciprocating multi-condition pin-on-disc tribometer of claim 2, wherein, The pin clamp includes a clamp housing and a fixing cylinder fixed to the lower end of the clamp housing. The fixing cylinder is provided with a fixing block and a fixing bolt. The upper end of the clamp housing is connected to a universal joint.

4. The compact reciprocating multi-condition pin-on-disc tribometer of claim 3, wherein, A first force sensor is provided between the upper end of the clamp housing and the universal joint; a second force sensor is provided between the rotating arm and the guide rod.

5. The compact reciprocating multi-condition pin-on-disc tribometer of claim 2, wherein, The frame is equipped with a liquid injection system, which includes a liquid tank, a liquid hose, a water pump, and a metal pipe connected in sequence. The liquid tank and the water pump are respectively fixed on the frame and the clamping platform.

6. The compact reciprocating multi-condition pin-on-disc tribometer of claim 2, wherein, The rack is equipped with an air-cooling system, which includes a bracket mounted on the rack, and the bracket is equipped with a fan and an air duct.

7. The compact reciprocating multi-condition pin-on-disc tribometer of claim 1, wherein, The frame is equipped with gear protective shells to protect the large bevel gear and the small bevel gear.

8. The compact reciprocating multi-condition pin-on-disc tribometer device of claim 1, wherein, The friction disc is mounted on the mounting plate by fixing screws.

9. A compact reciprocating multi-condition pin-on-disk friction test method, characterized in that, This method uses a compact reciprocating multi-condition pin-disc friction test apparatus as described in any one of claims 1-8, and specifically includes the following steps: Step 1: Select the friction disc and pin sample required for the experiment, and install the friction disc on the mounting plate and fix the pin sample to the fixing block with fixing bolts. Step 2: Start the cylinder to lower the pin sample to the upper surface of the friction disc, record the data through the first force sensor and obtain the real-time normal load, and adjust the output air pressure of the cylinder through the down-pressure closed-loop control method so that the real-time normal load reaches the set value. Step 3: Start the drive motor to drive the friction disc to reciprocate, and record the data through the second force sensor; Step 4: Process the data recorded by the second force sensor to obtain the real-time effective frictional force; Step five, determining the instantaneous friction coefficient according to the real-time normal load and the real-time effective friction force, and outputting a friction coefficient related curve.

10. The compact reciprocating multi-condition pin-on-disc friction test method of claim 9, wherein, The specific steps of the down pressure closed loop control method in the step two are as follows: Step 1, setting a target pressure spectrum according to experimental requirements; Step 2, the controller generates a target signal according to the target pressure spectrum; Step 3, reading the first force sensor signal and calculating the deviation of the first force sensor signal and the target signal, if the deviation is greater than a threshold deviation, the controller outputs an adjustment signal; Step 4, controlling the electric control valve on the gas cylinder to adjust the output gas pressure according to the adjustment signal; Step 5, repeating steps 3-4 until the deviation is less than or equal to the threshold deviation, and then ending the control.

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