CN106769102B - Device capable of continuously adjusting capacity and simulating load of automobile brake wheel cylinder - Google Patents

Abstract

The invention provides an automobile brake performance test load device with continuously adjustable containing cavity, which solves the problem that the existing automobile brake performance test platform needs to replace brakes with different specifications in the test process of different automobile types.

Description

A load device for simulating automobile brake wheel cylinder with continuously adjustable cavity

technical field

The invention relates to a device for simulating a brake of a braking system, more precisely, the invention relates to a load device for simulating a brake wheel cylinder of an automobile with a continuously adjustable cavity.

Background technique

Automobile braking performance test bench is a relatively common type of automobile test bench. The braking load part of the braking performance test bench is generally composed of real vehicle brakes. The principle is to form a back pressure through the brake wheel cylinder in the brake. braking load. Studies have shown that during the braking process of a car, the size of the brake wheel cylinder has a great influence on the reaction time, braking torque, and braking strength of the braking system. At the same time, the size of the brake wheel cylinder and the brake master cylinder Matching will also have a greater impact on braking performance, so brake wheel cylinders of different sizes have a great influence on the response characteristics of braking loads. However, due to the different volumes of the brake wheel cylinders of different models, the braking performance under the same working conditions is different. Therefore, when testing the performance of different models, the bench needs to be replaced with the brakes of the corresponding specifications, which is very important for the test. There are many unfavorable factors in the construction cost, space configuration, installation adjustment and experimental operation of the bench. In order to avoid the operation of replacing the brake, reduce the test cost, and optimize the space configuration of the stand, the invention provides a load device for simulating a brake wheel cylinder of an automobile with a continuously adjustable cavity.

Contents of the invention

The technical problem to be solved by the present invention is to overcome the problem that brakes of different specifications need to be replaced in the test process of different vehicle models in the existing automobile braking performance test bench, and propose a vehicle braking performance test load device with continuously adjustable cavity.

In order to solve the problems of the technologies described above, the present invention adopts the following specific technical solutions:

A load device for simulated automobile brake wheel cylinder with continuously adjustable cavity, characterized in that it includes a bottom bracket, the front end of the bottom bracket is fixed with a single-acting hydraulic cylinder through a vertical bracket, and the middle part of the bottom bracket is installed with an aluminum alloy through a slide rail. The profile is fixed with two linear slide rails, and there is a lead screw between the two linear slide rails. Between the linear slide rails, interference fit is adopted between the lead screw and the deep groove ball bearing, wherein one end of the lead screw passes through the end cover of the rear end bearing seat of the rear end bearing support, and the two linear slide rails are respectively installed There is a slider that can slide along the linear slide rail. The sliders on both sides are fixedly connected with the slider installation platform. A fixed support is fixed on the upper surface of the slider installation platform. The front end of the hydraulic cylinder piston rod and the top of the fixed support adopt The fastening nut is connected, the sliding sleeve and the sliding sleeve mounting plate are located at the front end of the slider, and the sliding sleeve relies on the internal thread and the external thread of the screw to install and cooperate, so that the sliding sleeve can move under the rotation of the screw and drive the sliding sleeve mounting plate and the sliding sleeve. The slide rail installation platform moves, and the slide rail installation platform drives the slider to slide along the linear slide rail. One end of the screw passing through the rear end bearing support is connected to the output shaft of a helical gear reducer fixed at the rear end of the bottom bracket through a coupling , the outside of the helical gear reducer is connected to the drive motor through the connecting shield, the input shaft inside the helical gear reducer is the output shaft of the drive motor, and a fixed angle iron at the measuring end of the displacement sensor is fixedly installed at the rear end of the slider installation platform. A pull-wire displacement sensor is fixedly installed on the top of the end cover of the rear-end bearing seat, and the stay wire of the pull-wire displacement sensor is between the pull-wire displacement sensor and the fixed angle iron at the measuring end of the displacement sensor.

Further technical solutions include:

The fixed support and the slide rail installation platform are fixedly connected by fastening screws, the sliding sleeve and a sliding sleeve mounting plate are connected by fastening screws, and the sliding sleeve mounting plate and the front end of the slider mounting platform are connected by fastening screws;

The screw is fixed on the center of the aluminum profile installed on the slide rail through deep groove ball bearings, front-end bearing support, rear-end bearing support and fastening screws, and the front-end bearing support and rear-end bearing support are fixed on the slide rail installation through fastening screws. The front and rear ends of the aluminum profile, the deep groove ball bearing and the rear end bearing support, the front end bearing support interference fit;

The linear slide rail is installed on the track plane on the upper surface of the aluminum profile on both sides of the slide rail. One end of the linear slide rail is against the rear surface of the front bearing support, and the other end is inserted into the through hole at the bottom of the cast right-angle seat through the fastening bolt and installed on the The slider nut inside the track plane is fixedly connected, and the front surface of the cast right-angle seat abuts against one end of the linear slide rail, and fixes the linear slide rail together with the front end bearing support.

The helical gear reducer is fixed on the rear end of the bottom bracket through a reducer mounting plate. The reducer mounting plate is a steel plate with a length of 190 mm, a width of 150 mm, and a thickness of 5 mm. There are four reducer mounting plates There are threaded holes with a diameter of 6mm at the corners, and four through holes with a diameter of 5mm in the middle of the reducer mounting plate, which correspond to the mounting holes at the bottom of the base of the helical gear reducer, and the reducer mounting plate is parallel to the device. The bottom bracket and the reducer mounting plate are fixedly connected with the slider nut and the bottom bracket through fastening screws passing through the threaded holes at the four corners.

The input end of the screw and the output end of the helical gear reducer are connected by a coupling. The coupling adopts a plum blossom coupling. The coupling consists of two coupling claws and an elastic element. The elastic claws are engaged with each other in the direction of the claws, and the radial occlusal gap is filled by plum blossom elastic elements. One end of the screw and the coupling claws are fixedly connected with the input end of the screw by a flat key. The claws at one end of the helical gear reducer It is also fixedly connected with the output shaft of the helical gear reducer with a flat key.

Compared with prior art, the advantages of the present invention are:

1) The present invention is driven by a motor, and the transmission mechanism drives the piston rod to move to change the size of the cavity of the simulated brake wheel cylinder to simulate the volume of the brake wheel cylinder of different models, so as to achieve the purpose of simulating the load of the brake wheel cylinder with different specifications;

2) The analog brake wheel cylinder with continuously adjustable volume can simulate brakes with different volume specifications to simulate the braking load, so it is not necessary to frequently replace the brakes when testing the braking performance of different models; it is conducive to simplifying the bench test operation;

3) The analog brake wheel cylinder with continuously adjustable volume can simulate brakes of different volume specifications to simulate the braking load, and there is no need to prepare brakes of different specifications, which can reduce the cost of the test bench;

4) From the aforementioned advantages, it can be seen that the test bench does not need to replace the brakes frequently, so when planning the space layout of the bench, there is no need to reserve space for replacing the brakes, which is conducive to optimizing the layout of the test bench;

Description of drawings

Below in conjunction with accompanying drawing, the patent of the present invention is described in detail:

Fig. 1 is a schematic diagram of the structural composition of a simulated automobile brake wheel cylinder load device with continuously adjustable cavity according to the present invention;

Fig. 2 is a top view of the structural composition of a simulated automobile brake wheel cylinder load device with continuously adjustable cavity according to the present invention;

Fig. 3 is a schematic diagram of a single-acting hydraulic cylinder of a continuously adjustable simulated automobile brake wheel cylinder loading device according to the present invention;

Fig. 4 is a schematic diagram of installation of a driving motor, a helical gear reducer and a shaft coupling of a simulated automobile brake wheel cylinder load device with continuously adjustable cavity according to the present invention;

Fig. 5 is a schematic diagram of a transmission mechanism of a simulated automobile brake wheel cylinder load device with continuously adjustable cavity according to the present invention;

Fig. 6 is a schematic diagram of the fixing method of the fixed support of a simulated automobile brake wheel cylinder load device with continuously adjustable cavity according to the present invention;

Fig. 7 is a schematic diagram of the fixing method of the front end bearing end cover of a simulated automobile brake wheel cylinder load device with continuously adjustable cavity according to the present invention;

Fig. 8 is a schematic diagram of a sliding sleeve installation and fixing method for a simulated automobile brake wheel cylinder load device with continuously adjustable cavity according to the present invention;

Fig. 9 is a schematic diagram of a fixing method of a cable-type displacement sensor of a simulated automobile brake wheel cylinder load device with continuously adjustable cavity according to the present invention;

Fig. 10 is a schematic diagram of the fixing method of the measurement end of a cable-type displacement sensor of a simulated automobile brake wheel cylinder load device with continuously adjustable cavity according to the present invention;

Fig. 11 is a schematic diagram of a coupling of a simulated automobile brake wheel cylinder load device with continuously adjustable cavity according to the present invention;

Fig. 12 is a schematic diagram of a coupling elastic element of a simulated automobile brake wheel cylinder load device with continuously adjustable cavity according to the present invention;

Fig. 13 is a coupling claw of a simulated automobile brake wheel cylinder load device with continuously adjustable cavity according to the present invention;

Fig. 14 is a control principle diagram of a driving motor of a simulated automobile brake wheel cylinder load device with continuously adjustable cavity according to the present invention.

In the figure: 1. Single-acting hydraulic cylinder, 2. Fixed rod of hydraulic cylinder, 3. Piston rod of hydraulic cylinder, 4. Sliding sleeve, 5. Fixed support, 6. Slider installation platform, 7. Fixed angle of measuring end of displacement sensor Iron, 8. Lead screw, 9. Pull wire displacement sensor, 10. End cover of rear end bearing seat, 11. Coupling, 12. Helical gear reducer, 13. Drive motor, 14. Bottom bracket, 15. Front end Bearing support, 16. Slide rail installation aluminum profile, 17. Slider, 18. Linear slide rail, 19. Pull wire displacement sensor fixing angle iron, 20. Rear end bearing support, 21. Reducer mounting plate, 22. Front end bearing support end cover, 23. deflation screw, 24. fastening screw, 25. fixing screw, 26. fastening nut, 27. sensor pull wire, 28. sliding sleeve mounting plate, 29. deep groove ball bearing. 30 fastening bolts, 31 cast right-angle seats, 32. slider nuts, 33. connecting shields.

Detailed ways:

The present invention is described in detail below in conjunction with accompanying drawing:

Referring to Fig. 1 and Fig. 2, a load device for simulated automobile brake wheel cylinder with continuously adjustable cavity according to the present invention includes a single-acting hydraulic cylinder 1, a hydraulic cylinder fixing rod 2, a hydraulic cylinder piston rod 3, and a sliding sleeve 4 , Fixed support 5, Slider installation platform 6, Lead screw 8, Pull wire displacement sensor 9, Coupling 11, Helical gear reducer 12, Drive motor 13, Bottom bracket 14, Front bearing support 15, Slide rail Install aluminum profile 16, slider 17, linear slide rail 18, rear end bearing support 20, reducer mounting plate 21, front end bearing support end cover 22, sliding sleeve mounting plate 28, deep groove ball bearing 29, connection shield 33 compositions.

A load device for simulated automobile brake wheel cylinders with continuously adjustable cavity, including a bottom bracket 14, a single-acting hydraulic cylinder 1 is fixedly installed on the front end of the bottom bracket through a vertical bracket, and an aluminum profile 16 is installed on the middle of the bottom bracket 14 through a slide rail Two linear slide rails 18 are fixed, and there is a lead screw 8 between the two linear slide rails 18. The lead screw 8 passes through the front end bearing support 15, the rear end bearing support 20 and the deep groove ball bearing 29 inside the corresponding support. Installed between two linear slide rails 18, an interference fit is adopted between the lead screw 8 and the deep groove ball bearing 29, and a slider 17 that can slide along the linear slide rail 18 is installed on the two linear slide rails 18. The side sliders 17 are all fixedly connected with the slider installation platform 6, and a fixed support 5 is fixed on the upper surface of the slider installation platform 6, and the front end of the hydraulic cylinder piston rod 3 is connected with the top of the fixed support 5 by a fastening nut 26, and the sliding The sleeve 4 and the sliding sleeve mounting plate 28 are located at the front end of the slider 17, and the sliding sleeve 4 is screwed into the screw 8 by means of the internal thread for installation, so that the sliding sleeve 4 can move under the rotation of the screw 8, and simultaneously drive the sliding sleeve mounting plate 28 and the screw 8. The slide rail installation platform 6, the slide rail installation platform 6 drives the slider 4 to slide along the linear slide rail 18, and the end of the lead screw 8 protruding from the rear end bearing support 20 is connected to an oblique fixed on the bottom bracket 14 rear end through the coupling 11. The output shaft of the toothed gear reducer 12 is connected, and the outside of the helical gear reducer 12 is connected to the drive motor through the connecting shield 33. The input shaft inside the helical gear reducer 12 is the output shaft of the drive motor 13, and the slider is installed on the platform 6 A fixed angle iron 7 at the measurement end of the displacement sensor is fixedly installed at the rear end, and a pull-wire displacement sensor 9 is fixedly installed on the top of the end cover 10 of the rear end bearing housing. The distance between the pull-wire displacement sensor 9 and the fixed angle iron 7 at the measurement end of the displacement sensor is The sensor stay wire 27 of stay wire displacement sensor 9.

The bottom bracket 14 of the device is a frame structure with a rectangular plane, which is composed of 2 longitudinal beams, 6 cross beams and 4 vertical beams. Four beams are evenly arranged between the two longitudinal beams, and are connected and fixed by casting right-angle seats 31, fastening screws 24 and slider nuts. The longitudinal beams are all made of 4040 profile, which is a square section with a side length of 40 mm and a profile with a T-shaped groove on each side. The length of the longitudinal beam in the embodiment is 1000 mm. The fastening bolt 30 used for fixed installation in the bottom bracket of the device is a special round head bolt of the model HOU6x12-6, the cast right angle seat 31 is a European standard connector of the model HOU3030, and the slider nut 32 is a model HOU5 -8-30 European standard connector. The front end of the bottom support is composed of four vertical beams and two cross beams, all of which are made of 3030 profile. The cast right-angle seat 31 is a European standard connector of model HOU3030, and the slider nut 32 is a European standard connector of model HOU5-8-30.

Referring to Fig. 3, a load device for simulated automobile brake wheel cylinders with continuously adjustable cavity adopts single-acting hydraulic cylinder 1. By changing the volume of hydraulic cylinder 1 to simulate the size of brake wheel cylinders, the braking load The response characteristics change to meet the requirements of simulating the braking load of different models. At the same time, the movement of the piston rod causes the position of the cable-type displacement sensor 9 to change, and the displacement indication of the cable-type displacement sensor 9 will be displayed on the sensor LCD screen. becomes the wheel cylinder volume information.

The single-acting hydraulic cylinder 1 selected is a single-acting hydraulic cylinder 1 with a model number of MOB-FA30*80. The hydraulic cylinder fixing rod 2 has a threaded one end passing through the fixing angle iron fixing holes on both sides and the cylinder support is fixed longitudinally. Hole, the inner hexagon cylindrical nut is screwed into the hydraulic cylinder fixed rod 2 thread to fix the oil cylinder and the fixed angle iron. The upper end of the cylinder body is provided with a threaded hole with a diameter of 6mm adjacent to the oil inlet side, and the air release screw 23 is installed on the upper end of the cylinder body through the threaded hole. The tail end of the piston rod 3 of the hydraulic cylinder has a thread, which can be fixedly connected with the fixed support 5 by a fastening nut 26 .

Referring to FIG. 4 , there are drive motor 13 , connecting shield 33 , helical gear reducer 12 , and reducer mounting plate 21 in the figure. The reducer mounting plate 21 is a steel plate with a length of 190 mm, a width of 150 mm, and a thickness of 5 mm. The four corners are provided with threaded holes with a diameter of 6 mm. The middle of the reducer mounting plate 21 is provided with four through holes with a diameter of 5 mm. correspond to the mounting holes at the bottom of the base of the device. The reducer mounting plate 21 is parallel to the bottom bracket 14 of the device, and the reducer mounting plate 21 is fixedly connected with the slider nut 32 and the bottom bracket 14 through the threaded holes at the four corners through fastening bolts 30 .

Referring to Fig. 5, Fig. 6, Fig. 7 and Fig. 8, the mechanism in the figure is composed of slide rail installation aluminum profile 16, linear slide rail 18, front end bearing support end cover 22, rear end bearing support end cover 10, lead screw 8, Sliding sleeve installation plate 28, slide block installation platform 6, linear slide rail 18, deep groove ball bearing 29, front end bearing support 15, rear end bearing seat 20, several fastening bolts 30 are formed.

The aluminum profile 16 for mounting the slide rail is a profile of HK120, and the material model is 6023T5. The fastening bolt 30 is inserted into the through hole at the bottom of the cast right-angle seat 31 and is fixedly connected with the slider nut 32 installed inside the bottom bracket 14 of the device. The profile 16 is fixed in a fixed position on the bottom bracket 14 .

The linear slide rail 18 is a linear slide rail of the type HGW4CC, and the linear slide rail 18 is designed with a special bundle structure to bear loads of up, down, left, and right at the same time. The two sets of guide rails are respectively installed on the track planes on the upper surfaces of the aluminum profiles 16 on both sides of the slide rails. One end of the linear slide rail 18 is against the rear surface of the front end bearing support 15 at the front end. The method for fixing the other end of the linear slide rail 18 is : The fastening bolt 30 is inserted into the through hole at the bottom of the cast right-angle seat 31 and is fixedly connected with the slider nut 32 installed inside the track plane. Fix the linear slide rail 18 together. The slide block 17 on the linear slide rail 18 has a self-locking nut. When adjusted to the target position, the self-locking nut can be tightened to fix the slide block 17 at a designated position and prevent the slide block 17 from loosening.

The model of the front end bearing support 15 selected is a bearing support of WBK17DF-WBK40DFF, and the fastening screws 24 pass through a total of four threaded holes at both ends of the bearing support and are fixedly connected with the threaded holes on the aluminum profile 16 installed on the slide rail. The deep groove ball bearing 29 installed inside the front end bearing support 15, the deep groove ball bearing 29 is a high carbon chromium bearing steel bearing model RQZC30200, the fastening bolt 30 passes through the thread of the end cover 22 of the front end bearing support The hole is fixedly connected with the threaded hole of the front end bearing support 15. Rear end bearing support 20 selects type, installation method and front end bearing support 15 to be consistent, difference is that the through hole that diameter is 20mm is provided with in the middle of rear end bearing support end cover 10, provides space for screw mandrel 8.

The lead screw 8 selected is a high-speed silent lead screw model XSVR01520, the front end of the lead screw 8 and the deep groove ball bearing 29 adopt an interference fit, the rear end of the lead screw 8 and the inner ring of the rear end deep groove ball bearing 29 adopt a surplus cooperation. The fastening screw 24 passes through the front end surface of the sliding sleeve 4 and the threaded hole of the sliding sleeve mounting plate 28 to fasten the sliding sleeve 4 with the sliding sleeve mounting plate 28 . The fastening screw 24 passes through the threaded hole on the front end surface of the sliding sleeve mounting plate 28 and the front end of the sliding block mounting platform 6 to securely connect the sliding sleeve mounting plate 28 to the slider mounting platform 6 . The fastening screw 24 passes through the counterbore on the upper surface of the slider mounting platform 6, and is screwed into the corresponding threaded hole with a diameter of 2mm on the slider 17, and the slider mounting platform 6 is fixedly connected with the sliders 17 on both sides. The fastening bolt 30 passes through the mounting hole of the fixed support 5 and is screwed into a threaded hole with a diameter of 2 mm on the upper surface of the slider installation platform 6 , so that the fixed support 5 is fixedly connected with the slider installation platform 6 . The fixed support 5 is fixedly connected with the hydraulic cylinder piston rod 3, and the specific method is: the fastening nut 26 is screwed into the thread on the hydraulic cylinder piston rod 3, and now one end of the hydraulic cylinder piston rod 3 passes through the upper end of the fixed support 5. In the installation hole, one side of the fastening nut 26 is close to the front surface of the fixed support 5. At this time, another fastening nut 26 is screwed into the thread of the hydraulic cylinder piston rod 3, so that the fastening nut 26 is close to the fixed support. 5 Rear surface.

The input shaft of the lead screw 8 and the output shaft of the helical gear reducer 12 are connected by a coupling 11. The coupling 11 is a high-strength plum-shaped coupling of the model KH8-20, and the fixing method is a keyway type fixed. Insert the input shaft of the lead screw 8 and the output shaft of the helical gear reducer 12 into the two ends of the coupling 11 respectively, so that the output shaft of the helical gear reducer 12 is fixedly connected with the input shaft of the lead screw 8 .

What described drive motor 13 selects for use is the model is YVP250M-2 three-phase frequency conversion speed regulation drive motor. What described gear reducer 12 selects is model is R47-Y11.5KW-4P-12.54 helical gear reducer 12, and installation mode is horizontal installation.

The drive motor 13 has four threaded holes with a diameter of 6 mm arranged in a circular array on the power output end housing, and the connecting shield 33 is also arranged with four threaded holes with a diameter of 6 mm on the same circumference toward one end of the motor. The two parts are fixedly connected by the screw 24 through the threaded hole connecting the drive motor 13 and the shield 33 . The connecting shield 33 arranges four threaded holes with a diameter of 6 mm on the circumference of one end of the helical gear reducer 12, and arranges four threaded holes with a diameter of 6 mm around the input shaft of the helical gear reducer 12 in the same circular array. The two parts are fixedly connected by the screw 24 through the threaded hole of the helical gear reducer 12 and the connecting shield 33 . What fastening screw 24 has chosen is the special round head screw that model is HOU-6x12-6. Each corner of the base of the helical gear reducer 12 is provided with a through hole with a diameter of 6mm. The arrangement of the through holes is consistent with the arrangement of the through holes on the accelerator mounting plate 21. The through hole is fixedly connected with the fastening nut 26 close to the lower surface of the reducer mounting plate 21 .

The circuit diagram of the forward and reverse control circuit of the three-phase variable frequency speed regulation drive motor is shown in Figure 13, SB1 is the forward rotation start button, SB2 is the reverse rotation start button, and there is another stop button SB3, Q1 and Q2 are relays , M is a three-phase AC motor. Its working principle is: when rotating forward, press the button SB1, the relay Q1 will absorb power and lock itself, its normally open contact will be closed, and the motor will run normally; when it is stopped, press the button SB3, K1 will be de-energized and released, and the motor will stop. When reversing, press the button SB2, the relay K2 is energized and self-locked, its normally open contact is closed, and the motor runs in reverse; when stopping, press the button SB3, K2 is de-energized and released, and the motor stops. The control circuit is connected in series with the normally closed auxiliary contact of the internal thermal relay of the inverter to improve the circuit protection performance.

Referring to Fig. 9, Fig. 10, the type that described pull-type displacement sensor 9 selects is the small range pull-type displacement sensor of MPS-XS-4-20mA, and the both sides of pull-type displacement sensor 9 are respectively provided with the installation that diameter is 4mm. Threaded holes, while two installation threaded holes with a diameter of 4mm are arranged on the upper end of the rear end bearing support 20, the method for installing the pull-wire displacement sensor 9 on the rear-end bearing support 20 is: each side is fixed by a pull-wire displacement sensor The angle iron 19 and two fastening screws 24 securely connect the pull-wire displacement sensor 9 to the rear end bearing support 20, and the measuring end of the pull-wire displacement sensor 9 is fixed by the angle iron 7 and the fastening nut 26 at the measuring end of the displacement sensor Fixed on the slider installation platform 6, the measuring end and the pull-wire displacement sensor 9 will be connected by silk wires. The pull-wire displacement sensor 12 is installed on the central axis of the slider installation platform 6. The measuring end of the displacement displacement sensor is fixed with an angle iron 7, and the pulling measuring end is fixed. The gasket is close to the surface of the front end of the fixed angle iron 7 at the measuring end of the displacement sensor, and the fastening nut 26 is tightened with the threaded joint on the other side of the fixed angle iron 7, and the measuring end of the displacement sensor is fixed on the slider installation platform 6. When the slider installation platform 6 moves, the movement of the slider installation platform 6 drives the sensor measuring end to move. At this time, the pull-wire displacement sensor 9 outputs displacement information on its display screen, which is converted into the volume information of the simulated wheel cylinder by calculation.

The working principle of a simulated automobile brake wheel cylinder load device with continuously adjustable cavity is as follows:

Referring to Fig. 1 and Fig. 2, a kind of simulated car brake wheel cylinder load device with adjustable cavity is shown in the figure.

A continuously adjustable analog car brake wheel cylinder load device uses a variable volume hydraulic cylinder to replace the original real vehicle brake wheel cylinder, and increases or decreases the wheel cylinder brake in the braking circuit by controlling the volume of the wheel cylinder. The increase or decrease of fluid volume can control the change of brake pressure. This adjustment method is called variable volume pressure adjustment. The available references for its principle basis: model test on the rate of change of the brake pressure of automobile ABS (published in the "Journal of Agricultural Machinery", No. 9, Volume 38, September 2007, authors: Li Zhiyuan, Liu Zhaodu, Cui Haifeng, Wang Renguang):

In this paper, the dynamic equations of boosting and pressure-holding stages during braking are as follows:

The dynamic equation of the supercharging stage when the car brakes:

The winter equation of the pressure holding stage when the car brakes:

Where V ₀ is the volume of the wheel cylinder, p _c is the pressure of the wheel cylinder, K _c is the equivalent bulk elastic modulus of the wheel cylinder, R _e is the equivalent liquid resistance during the pressurization process, and R _e ' is the equivalent liquid resistance during the decompression process , p _v is the wheel cylinder inlet pressure, h ₁ and h ₂ are the throttle valve index. It can be seen that the volume of the wheel cylinder will affect the performance of the pressure and decompression process of the automobile braking system, so the load of the brake wheel cylinder of each model is simulated by changing the volume of the brake wheel cylinder.

The specific use process is as follows:

The load device for simulated automobile brake wheel cylinders with continuously adjustable cavity according to the present invention needs to connect the input port of the single-acting hydraulic cylinder 1 to the brake main body of the bench through the brake pipeline before the bench test. The output port of the cylinder ensures the sealing of the output pipeline, and ensures that the brake hydraulic oil in the output pipeline can be input without loss to a single-acting hydraulic cylinder 1 with a continuously adjustable cavity that simulates the load device of the brake wheel cylinder of an automobile. The motor part needs to be connected to the power supply circuit to ensure the normal operation of the drive motor 13. The pull-wire displacement sensor 9 also needs to be powered on, and the hydraulic cylinder piston rod 2 of the single-acting piston cylinder 1 is guaranteed to be at the zero working volume position. The reading of the cable-type displacement sensor is zero-adjusted. By obtaining the volume information of the simulated target brake wheel cylinder, it is calculated as the displacement of the piston rod when the target simulated volume is obtained, and the calculated displacement is used as the target displacement to control the drive motor 13 The positive and negative rotation of the single-acting hydraulic cylinder achieves the purpose of simulating the volume of the brake wheel cylinder.

When the load device of the simulated automobile brake wheel cylinder with continuously adjustable volume cavity according to the present invention works initially, the piston rod 3 of the single-acting hydraulic cylinder is at the initial position, that is, the working space of the single-acting hydraulic cylinder 1 is zero. Record this When the reading W ₁ of the pull-wire displacement sensor 9 is displayed, the oil inlet end of the single-acting hydraulic cylinder 1 is connected to the brake pipeline branched from the brake master cylinder, and at the same time, the drive motor 13 of the device is energized, and the switch motor is pressed. Forward rotation, the drive motor 13 works to drive the helical gear reducer 12 to rotate, the output shaft of the helical gear reducer 12 drives the screw 8 to rotate through the coupling 11, and the lead screw 8 rotates to drive the sliding sleeve 4, the sliding sleeve mounting plate 28, Slider mounting platform 6, slider 17 and fixed support 5 move to the rear end of the device at the same time, and the movement of fixed support 5 drives the movement of hydraulic cylinder piston rod 3. At this time, the working volume of single-acting hydraulic cylinder 1 will become larger. Press the reversing switch of the driving motor 13, the lead screw 8 rotates reversely, the sliding sleeve 4 drives the sliding sleeve mounting plate 28, the sliding block mounting platform 6, and the fixed support 5 to move to the front end, and the single-acting hydraulic cylinder piston rod 3 is fixed Driven by the support 5, it moves in the reverse direction, and the working volume of the single-acting hydraulic cylinder 1 becomes smaller accordingly. Press the stop button of the driving motor 13, the hydraulic cylinder piston rod 3 will be fixed at the current position due to the self-locking of the screw rod 8, and the measuring end of the pull-wire displacement sensor 9 will change with the moving position of the slider installation platform 6. The cable-type displacement sensor 9 shows the number W ₂ , and the volume information of the simulated brake wheel cylinder can be calculated according to the changes in the readings of the front and rear displacement sensors. The specific calculation formula is as follows:

V=(W ₁ -W ₂ )×S

V is the volume of the wheel cylinder, W ₁ is the displacement indication of the motor of the wire displacement sensor before operation, W ₂ is the displacement indication of the motor of the wire displacement sensor after operation, and S is the cavity cross-sectional area of the single-acting hydraulic cylinder.

Claims (4)

1. a continuously adjustable simulated automobile brake wheel cylinder loading device with a cavity, is characterized in that it comprises a bottom bracket (14), and the front end of the bottom bracket (14) is fixedly installed with a single-acting hydraulic cylinder ( 1), the middle part of the bottom bracket (14) is fixed with two linear slide rails (18) through the slide rail installation aluminum profile (16), and there is a lead screw (8) between the two linear slide rails (18), and the lead screw ( 8) The front end bearing support (15), the rear end bearing support (20) and the deep groove ball bearings (29) inside the above two supports are installed between the two linear slide rails (18), and the lead screw ( 8) and the deep groove ball bearing (29) adopt an interference fit, wherein one end of the lead screw (8) passes through the rear end bearing seat end cover (10) of the rear end bearing support (20), two A slide block (17) that can slide along the linear slide rail (18) is respectively installed on the linear slide rail (18), and the slide blocks (17) on both sides are fixedly connected with the slide block mounting platform (6). (6) A fixed support (5) is fixed on the upper surface. The front end of the hydraulic cylinder piston rod (3) is connected with the top of the fixed support (5) by a fastening nut (26). The sliding sleeve (4) and the sliding sleeve are installed The plate (28) is located at the front end of the slider (17), and the sliding sleeve (4) relies on the internal thread to fit with the external thread of the lead screw (8), so that the sliding sleeve (4) can move under the rotation of the lead screw (8) Simultaneously drive the sliding sleeve mounting plate (28) and the slide rail mounting platform (6) to move, the slide rail mounting platform (6) drives the slide block (17) to slide along the linear slide rail (18), the slide block (17) has a self-locking nut , when adjusted to the target position, tighten the self-locking nut to fix the slider (17) at the specified position, and the end of the screw (8) passing through the rear end bearing support (20) is fixed on the The output shaft of a helical gear reducer (12) at the rear end of the bottom bracket (14) is connected. The internal input shaft is the output shaft of the drive motor (13), the rear end of the slider mounting platform (6) is fixedly installed with a displacement sensor measuring end fixed angle iron (7), and the top of the rear end bearing housing end cover (10) is fixedly installed There is a backguy type displacement sensor (9), and between the backguy type displacement sensor (9) and the fixed angle iron (7) of the displacement sensor measuring end is the sensor backguy (27) of the backguy type displacement sensor (9). 2. A continuously adjustable analog automobile brake wheel cylinder loading device according to claim 1, characterized in that: The fixed support (5) and the slide rail installation platform (6) are fixedly connected by fastening screws (24), the sliding sleeve (4) is connected with a sliding sleeve mounting plate (28) by fastening screws (24), and the sliding sleeve is installed Plate (28) and slide block installation platform (6) front end are connected by fastening screw (24); Lead screw (8) is fixed on the center of slide rail installation aluminum profile (16) through deep groove ball bearing (29), front end bearing support (15), rear end bearing support (20) and fastening screw (24), front end The bearing support (15) and the rear end bearing support (20) are fixed on the front and rear ends of the slide rail installation aluminum profile (16) by fastening screws (24), and the deep groove ball bearing (29) and the rear end bearing support ( 20), front end bearing support (15) interference fit; The linear slide rail (18) is installed on the track plane on the upper surface of the aluminum profile (16) on both sides of the slide rail. One end of the linear slide rail (18) is against the rear surface of the front bearing support (15), and the other end is fastened The bolt (30) is inserted into the through hole at the bottom of the cast right-angle seat (31) and fixedly connected with the slider nut (32) installed inside the track plane, and the front surface of the cast right-angle seat (31) leans against one end of the linear slide rail (18) , together with the front end bearing support (15) the linear slide rail (18) is fixed. 3. A load device for simulated automobile brake wheel cylinders with continuously adjustable cavity according to claim 1, characterized in that: said helical gear reducer (12) passes through a reducer mounting plate (21) Fixed on the rear end of the bottom bracket (14), the reducer mounting plate (21) is a steel plate with a length of 190mm, a width of 150mm, and a thickness of 5mm. The four corners of the reducer mounting plate (21) are provided with diameters The threaded hole is 6mm, and four through holes with a diameter of 5mm are arranged in the middle of the reducer mounting plate (21), corresponding to the mounting holes at the bottom end of the base of the helical gear reducer (12), and the reducer mounting plate (21 ) is parallel to the bottom bracket (14) of the device, and the reducer mounting plate (21) is fixedly connected with the slider nut (32) and the bottom bracket (14) through the threaded holes at the four corners by fastening screws (24). 4. A load device for analog automobile brake wheel cylinders with continuously adjustable cavity according to claim 1, characterized in that: the input end of the lead screw (8) and the output end of the helical gear reducer (12) Use the coupling (11) to connect. The coupling (11) is a plum blossom coupling. The coupling (11) is composed of two coupling claws and an elastic element. The two elastic claws are on the claw The directions interlock with each other, and the position of the radial interlocking gap is filled by plum blossom elastic elements. One end of the lead screw (8) and the coupling claw and the input end of the lead screw (8) are fixedly connected by a flat key, and one end of the helical gear reducer (12) The output shaft of the claw and the helical gear reducer (12) is fixedly connected by a flat key equally.

Images