Differential lock locking function test bed and test method thereof

Abstract

The invention relates to the technical field of differential lock detection, and discloses a differential lock locking function test bench and a test method thereof.The test bench comprises an automobile rear axle, a differential lock, a magnetic powder clutch and a variable frequency motor, and the differential lock is carried on the automobile rear axle and comprises an input shaft, a left half shaft and a right half shaft; the magnetic powder clutch and the variable frequency motor are fixed on an automobile rear axle, the magnetic powder clutch is connected with a left half shaft through the torque sensor, and a power shaft of the variable frequency motor is also connected with an input shaft through the torque sensor. The differential lock test bench has the following beneficial effects: 1, the test of the differential lock is completed through the test bench, the test bench is not limited by sites, the test cost can be greatly reduced, and the convenience is improved; and 2, the test of the differential lock is completed through the test bench, so that the test result is more accurate. And 3, the test bench can be used for testing in two different modes, so that the convenience of the test is improved.

Description

Technical Field

[0001] The invention relates to the technical field of differential lock detection, and in particular to a differential lock locking function test bench and a test method thereof. Background Art

[0002] With the continuous development of automobile technology, the requirements for vehicle maneuverability, passability and other performance are getting higher and higher. Differential locks play an important role in improving vehicle performance and maintaining vehicle driving stability. Therefore, it is necessary to test and verify the performance of differential locks. The core function of differential locks is achieved through the locking mechanism, that is, to verify the locking function of differential locks.

[0003] The significance of the differential lock test is that it can verify whether the locking function of the differential lock is normal under different working conditions, so as to ensure the safety and stability of vehicle driving; based on the test data, the problems with the differential lock can be found and improved, and it can be used as the basis for its performance.

[0004] At present, the commonly used differential lock test method is the whole vehicle road test. The differential lock to be tested is installed on the test vehicle, and the necessary test equipment is installed. Different road conditions are simulated on the site, and the vehicle completes the required test conditions. The corresponding data is collected to achieve the test objectives. This test method is limited by the site and is easily affected by other parts of the vehicle and human factors. The overall cost is too high. The overall structure of the existing differential lock fatigue test bench is relatively complex, the equipment cost is high, and maintenance and operation may also be relatively difficult; it occupies a large space, which limits the place of use. Summary of the invention

[0005] In order to solve the above problems, the present invention provides a differential lock locking function test bench and a test method thereof, and the present invention is implemented through the following technical solutions.

[0006] A differential lock function test bench comprises a rear axle of a vehicle, a differential lock, a magnetic powder clutch and a variable frequency motor, wherein the differential lock is mounted on the rear axle of the vehicle, the differential lock comprises an input shaft, a left half shaft and a right half shaft, the magnetic powder clutch and the variable frequency motor are fixed on the rear axle of the vehicle, the magnetic powder clutch is connected to the left half shaft through a torque sensor, and the power shaft of the variable frequency motor is also connected to the input shaft through the torque sensor.

[0007] As a further solution of the present invention, two speed display meters are fixedly connected to the rear axle of the vehicle, the left half shaft and the right half shaft respectively pass through the detection through hole of one of the speed display meters, and a temperature display meter is fixedly connected to the housing of the differential lock, and the detection end of the temperature display meter extends into the housing of the differential lock.

[0008] As a further solution of the present invention, it also includes 220V AC mains power, the 220V AC mains power includes a live wire and a neutral wire, the live wire is electrically connected to the anode terminal of the magnetic powder clutch, the torque sensor, the speed display meter and the temperature display meter through a circuit breaker, and the cathode terminal of the magnetic powder clutch, the torque sensor, the speed display meter and the temperature display meter is electrically connected to the neutral wire.

[0009] As a further solution of the present invention, the three-phase terminals of the variable frequency motor are electrically connected to the three-phase output terminals of the inverter, and the three-phase input terminals of the inverter are connected to the three-phase lines of the 380V external power supply through AC contactors and fuses in turn.

[0010] As a further solution of the present invention, it also includes a PLC controller, the model of the PLC controller is MELSECFX1S-20MT, the power interfaces L and N of the PLC controller are electrically connected to the live wire and the neutral wire of the 220V AC mains, respectively, and the output COM terminal of the PLC controller is connected in parallel with the X0, X1, X2, X3, X4, X5, X6, X7 and X10 interfaces of the PLC controller through switches SB1~SB9.

[0011] As a further solution of the present invention, the switches SB1 and SB4 are connected in parallel to the control circuit of the variable frequency motor. When the switch SB1 is turned on, the variable frequency motor operates at a constant speed. When the switch SB4 is turned on, the speed of the variable frequency motor increases to a predetermined test speed and is maintained. The switches SB2 and SB5 are connected in parallel to the control circuit of the differential lock. When the switch SB2 or SB5 is turned on, the differential lock is energized. When the switch SB2 or SB5 is turned off, the differential lock is energized.

[0012] As a further solution of the present invention, a switching power supply is further included, wherein the switching power supply is used to convert the 220V AC mains power into a 12V DC power output, the positive output terminal of the switching power supply is electrically connected to the Y0, Y1, Y3 and Y4 interfaces of the PLC controller through relays KA1, KA2, KA3 and KA4 respectively, and the negative output terminal of the switching power supply is electrically connected to the input terminals COM0, COM1, COM2, COM3 and COM4 interfaces of the PLC controller; The switches SB3 and SB6 are manual switches, and the switches SB1, SB2, SB4 and SB5 are electromagnetic switches, and are controlled on and off by relays KA1, KA2, KA3 and KA4 respectively.

[0013] A differential lock function test method has two test modes: mode 1 and mode 2. Switches SB3 and SB6 are mode selection switches.

[0014] As a further solution of the present invention, the process of mode 1 is as follows: S1, mode selection, switch SB3 is closed, and mode 1 is selected for testing; S2, the variable frequency motor operates at a constant speed, and the magnetic powder clutch applies load to the left half shaft; S3, the differential lock is powered off and unlocked, the left and right half shafts form a speed difference, and run for a preset time; S4, the differential lock is powered on and locked, the left and right half shafts rotate synchronously, and run for a preset time; S5, repeat steps S3 and S4.

[0015] As a further solution of the present invention, the process of Mode 2 is as follows: T1, mode selection, switch SB6 is closed, and mode 2 is selected for testing; T2, the magnetic powder clutch applies load to the left half shaft; T3, the differential lock is powered on and locked, the left and right half shafts rotate synchronously, and the speed of the variable frequency motor increases to the predetermined test speed and runs for a preset time; T4, the differential lock is powered off and unlocked, and the left and right half shafts have a speed difference, which runs for a preset time; T5, the variable frequency motor is powered off, and the speed of the variable frequency motor drops to zero; T6, repeat steps T3 to T5.

[0016] The beneficial effects of the present invention are as follows: 1. This application uses a test bench to complete the test of the differential lock. Compared with the traditional vehicle test, this application is not restricted by the site and can greatly reduce the cost of the test and improve convenience.

[0017] 2. In the traditional method of testing the differential lock by testing the whole vehicle, the test result is easily affected by other parts of the vehicle, and the test result is not accurate enough. This application uses a test bench to complete the differential lock test, which can make the test result more accurate.

[0018] 3. The test bench of the present application can conduct tests in two different modes, thus improving the convenience of the test. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solution of the present invention, the drawings required for use in the description of the specific implementation methods will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 : A structural schematic diagram of a differential lock locking function test bench according to the present invention; Figure 2: Schematic diagram of 220V AC mains power supply; Figure 3 : Schematic diagram of power connection of variable frequency motor; Figure 4 : Circuit connection diagram of PLC controller; Figure 5 :Flowchart of Mode 1; Figure 6 :Flowchart of mode 2.

[0021] The reference numerals are as follows: 1-car rear axle, 2-differential lock, 21-input shaft, 22-left half shaft, 23-right half shaft, 3-magnetic powder clutch, 4-frequency conversion motor, 41-frequency converter, 42-AC contactor, 43-fuse, 44-380V external power supply, 5-torque sensor, 6-speed display meter, 7-temperature display meter, 81-live wire, 82-neutral wire, 83-circuit breaker, 9-PLC controller, 10-switching power supply. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] like Figure 1-6 As shown, a differential lock locking function test bench includes a vehicle rear axle 1, a differential lock 2, a magnetic powder clutch 3 and a frequency conversion motor 4. The differential lock 2 is mounted on the vehicle rear axle 1. The differential lock 2 includes an input shaft 21, a left half shaft 22 and a right half shaft 23. The magnetic powder clutch 3 and the frequency conversion motor 4 are fixed on the vehicle rear axle 1. The magnetic powder clutch 3 is connected to the left half shaft 22 through a torque sensor 5. The power shaft of the frequency conversion motor 4 is also connected to the input shaft 21 through the torque sensor 5.

[0024] like Figure 1 As shown, the power shaft of the variable frequency motor 4 is connected to the input shaft 21, which is used to drive the input shaft 21 to rotate. The input shaft 21 drives the left half shaft 22 and the right half shaft 23 to rotate through the differential lock 2. The torque at the input shaft 21 and the left half shaft 22 can be detected by the torque sensor 5. When the magnetic powder clutch 3 is energized, the left half shaft 22 is loaded. When the differential lock 2 is locked and disconnected, the rotation speeds of the left half shaft 22 and the right half shaft 23 change, thereby simulating the locking condition of the differential lock 2 during the actual operation of the vehicle. The durability and stability of the differential lock 2 are detected by the cyclic test.

[0025] Preferably, two speed display gauges 6 are fixedly connected to the rear axle 1 of the automobile, and the left half shaft 22 and the right half shaft 23 respectively pass through the detection through hole of one of the speed display gauges 6. A temperature display gauge 7 is fixedly connected to the housing of the differential lock 2, and the detection end of the temperature display gauge 7 extends into the housing of the differential lock 2.

[0026] like Figure 1 As shown, the rotation speed of the left half shaft 22 and the right half shaft 23 can be detected by the rotation speed display meter 6, and the temperature display meter 7 can detect the temperature inside the housing of the differential lock 2.

[0027] Preferably, it also includes 220V AC mains power, which includes a live wire 81 and a neutral wire 82. The live wire 81 is electrically connected to the anode terminal of the magnetic powder clutch 3, the torque sensor 5, the speed display meter 6 and the temperature display meter 7 through a circuit breaker 83, and the cathode terminal of the magnetic powder clutch 3, the torque sensor 5, the speed display meter 6 and the temperature display meter 7 is electrically connected to the neutral wire 82.

[0028] like Figure 2 As shown, the magnetic powder clutch 3, the torque sensor 5, the speed display meter 6 and the temperature display meter 7 are powered by 220V AC mains electricity.

[0029] Preferably, the three-phase terminals of the variable frequency motor 4 are electrically connected to the three-phase output terminals of the inverter 41, and the three-phase input terminals of the inverter 41 are connected to the three-phase lines of the 380V external power supply 44 through the AC contactor 42 and the fuse 43 in sequence.

[0030] like Figure 3 As shown, the variable frequency motor 4 is powered by a 380V external power supply 44 , the fuse 43 is used to protect the variable frequency motor 4 , and the frequency converter 41 is used to control the rotation speed of the variable frequency motor 4 .

[0031] Preferably, a PLC controller 9 is also included, the model of the PLC controller 9 is MELSEC FX1S-20MT, the power interfaces L and N of the PLC controller 9 are electrically connected to the live wire 81 and the neutral wire 82 of the 220V AC mains respectively, and the output COM terminal of the PLC controller 9 is connected in parallel with the X0, X1, X2, X3, X4, X5, X6, X7 and X10 interfaces of the PLC controller 9 through switches SB1~SB9 respectively.

[0032] like Figure 4 As shown, switches SB1 to SB9 are controlled by a PLC controller 9 .

[0033] Preferably, switches SB1 and SB4 are connected in parallel to the control circuit of the variable frequency motor 4. When switch SB1 is turned on, the variable frequency motor 4 operates at a constant speed. When switch SB4 is turned on, the speed of the variable frequency motor 4 increases to a predetermined test speed and is maintained. Switches SB2 and SB5 are connected in parallel to the control circuit of the differential lock 2. When switch SB2 or SB5 is turned on, the differential lock 2 is energized. When switch SB2 or SB5 is turned off, the differential lock 2 is de-energized.

[0034] Preferably, a switching power supply 10 is further included, and the switching power supply 10 is used to convert 220V AC mains power into 12V DC power output, and the positive output terminal of the switching power supply 10 is electrically connected to the Y0, Y1, Y3 and Y4 interfaces of the PLC controller 9 through relays KA1, KA2, KA3 and KA4 respectively, and the negative output terminal of the switching power supply 10 is electrically connected to the input terminals COM0, COM1, COM2, COM3 and COM4 interfaces of the PLC controller 9; Switches SB3 and SB6 are manual switches, and switches SB1, SB2, SB4 and SB5 are electromagnetic switches, and their on and off are controlled by relays KA1, KA2, KA3 and KA4 respectively.

[0035] By programming the PLC controller 9, the on and off of relays KA1, KA2, KA3 and KA4 can be controlled, thereby controlling the on and off of switches SB1, SB2, SB4 and SB5, and the relay duration of relays KA1, KA2, KA3 and KA4 can control the on-time of switches SB1, SB2, SB4 and SB5, thereby controlling the variable frequency motor 4 and the differential lock 2.

[0036] A differential lock 2 locking function test method has two test modes: mode 1 and mode 2. Switches SB3 and SB6 are mode selection switches.

[0037] like Figure 5 As shown, preferably, the process of mode 1 is as follows: S1, mode selection, switch SB3 is closed, and mode 1 is selected for testing; When switch SB3 is turned on, it indicates that the test is carried out in mode 1. At this time, relays KA1 and KA2 control the on and off of switches SB1 and SB2.

[0038] S2, the variable frequency motor 4 operates at a constant speed, and the magnetic powder clutch 3 applies a load to the left half shaft 22; First, the relay KA1 controls the switch SB1 to be turned on, the variable frequency motor 4 operates at a constant speed, and the magnetic powder clutch 3 applies a load to the left half shaft 22; S3, the differential lock 2 is powered off and unlocked, and the left half shaft 22 and the right half shaft 23 form a speed difference, and run for a preset time; In the initial state, the switch SB2 is turned off, and the left half shaft 22 forms a speed difference with the right half shaft 23 under the load of the magnetic powder clutch 3 and runs for a period of time.

[0039] S4, the differential lock 2 is powered on and locked, and the left half shaft 22 and the right half shaft 23 rotate synchronously for a preset time; Then relay KA2 controls switch SB2 to turn on, differential lock 2 is energized and locked, and the left half shaft 22 and the right half shaft 23 rotate synchronously and run for a period of time.

[0040] S5, repeat steps S3 and S4.

[0041] Mode 1 can verify the life fatigue test of the differential lock 2 when the variable frequency motor 4 is at a fixed speed.

[0042] like Figure 6 As shown, preferably, the process of mode 2 is as follows: T1, mode selection, switch SB6 is closed, and mode 2 is selected for testing; When switch SB6 is turned on, it indicates that the test is carried out in mode 2. At this time, relays KA3 and KA4 control the on and off of switches SB4 and SB5.

[0043] T2, the magnetic powder clutch 3 applies a load to the left half shaft 22; T3, the differential lock 2 is powered on and locked, the left half shaft 22 and the right half shaft 23 rotate synchronously, and the speed of the variable frequency motor 4 increases to a predetermined test speed and runs for a preset time; First, relay KA4 controls switch SB5 to close, and differential lock 2 is energized and locked. Then relay KA3 controls switch SB4 to close, and the speed of variable frequency motor 4 increases to a predetermined test speed and runs for a preset time.

[0044] T4, the differential lock is powered off and unlocked, and a speed difference is generated between the left half shaft 22 and the right half shaft 23, and the operation lasts for a preset time; After a period of time, the relay KA4 controls the switch SB5 to be disconnected, the differential lock 2 is powered on, off and unlocked, and a speed difference is generated between the left half shaft 22 and the right half shaft 23.

[0045] T5, the variable frequency motor 4 is powered off, and the speed of the variable frequency motor 4 drops to zero; After a period of time, the relay KA3 controls the switch SB4 to be disconnected, the variable frequency motor 4 is powered off, and the speed of the variable frequency motor 4 drops to zero.

[0046] T6, repeat steps T3 to T5.

[0047] Cyclic test, test mode 2 is used to simulate the working condition that after a car passes through complex road conditions with differential lock 2 locked, it can automatically disengage as the speed increases to a certain stage.

[0048] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to only specific implementation methods. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A differential lock function test bench, comprising a vehicle rear axle (1), a differential lock (2), a magnetic powder clutch (3) and a variable frequency motor (4), characterized in that: The differential lock (2) is mounted on the rear axle (1) of the vehicle, and comprises an input shaft (21), a left half shaft (22) and a right half shaft (23). The magnetic powder clutch (3) and the variable frequency motor (4) are fixed on the rear axle (1) of the vehicle, the magnetic powder clutch (3) and the left half shaft (22) are connected via a torque sensor (5), and the power shaft of the variable frequency motor (4) and the input shaft (21) are also connected via the torque sensor (5).

2. A differential lock (2) locking function test bench according to claim 1, characterized in that: Two speed display meters (6) are fixedly connected to the rear axle (1) of the automobile, the left half shaft (22) and the right half shaft (23) respectively pass through a detection through hole of one of the speed display meters (6), and a temperature display meter (7) is fixedly connected to the housing of the differential lock (2), and a detection end of the temperature display meter (7) extends into the housing of the differential lock (2).

3. A differential lock (2) locking function test bench according to claim 2, characterized in that: The invention also includes a 220V AC mains power supply, wherein the 220V AC mains power supply includes a live wire (81) and a neutral wire (82), wherein the live wire (81) is electrically connected to the anode terminal of the magnetic powder clutch (3), the torque sensor (5), the speed display meter (6) and the temperature display meter (7) through a circuit breaker (83), and the cathode terminal of the magnetic powder clutch (3), the torque sensor (5), the speed display meter (6) and the temperature display meter (7) is electrically connected to the neutral wire (82).

4. A differential lock (2) locking function test bench according to claim 3, characterized in that: The three-phase connection terminals of the variable frequency motor (4) are respectively electrically connected to the three-phase output terminals of the frequency converter (41), and the three-phase input terminals of the frequency converter (41) are respectively connected to the three-phase lines of the 380V external power supply through the AC contactor (42) and the fuse (43).

5. A differential lock (2) locking function test bench according to claim 4, characterized in that: The invention also comprises a PLC controller (9), wherein the model of the PLC controller (9) is MELSEC FX1S-20MT, the power supply interfaces L and N of the PLC controller (9) are respectively electrically connected to the live wire (81) and the neutral wire (82) of the 220V AC mains power, and the output COM terminal of the PLC controller (9) is respectively connected in parallel to the X0, X1, X2, X3, X4, X5, X6, X7 and X10 interfaces of the PLC controller (9) through switches SB1 to SB9.

6. A differential lock (2) locking function test bench according to claim 5, characterized in that: The switches SB1 and SB4 are connected in parallel to the control circuit of the variable frequency motor (4); when the switch SB1 is turned on, the variable frequency motor (4) operates at a constant speed; when the switch SB4 is turned on, the speed of the variable frequency motor (4) increases to a predetermined test speed and is maintained; the switches SB2 and SB5 are connected in parallel to the control circuit of the differential lock (2); when the switch SB2 or SB5 is turned on, the differential lock (2) is energized; when the switch SB2 or SB5 is turned off, the differential lock (2) is de-energized.

7. A differential lock (2) locking function test bench according to claim 6, characterized in that: It also includes a switching power supply (10), the switching power supply (10) is used to convert 220V AC mains power into a 12V DC power output, the positive output terminal of the switching power supply (10) is electrically connected to the Y0, Y1, Y3 and Y4 interfaces of the PLC controller (9) through relays KA1, KA2, KA3 and KA4 respectively, and the negative output terminal of the switching power supply (10) is electrically connected to the input terminals COM0, COM1, COM2, COM3 and COM4 of the PLC controller (9); The switches SB3 and SB6 are manual switches, and the switches SB1, SB2, SB4 and SB5 are electromagnetic switches, and are controlled on and off by relays KA1, KA2, KA3 and KA4 respectively.

8. A differential lock (2) locking function test method, implemented based on a differential lock (2) locking function test bench according to claim 7, characterized in that: The test method has two test modes: mode 1 and mode 2. Switches SB3 and SB6 are mode selection switches.

9. A differential lock (2) locking function test method according to claim 8, characterized in that: The process of mode 1 is as follows: S1, mode selection, switch SB3 is closed, and mode 1 is selected for testing; S2, the variable frequency motor (4) operates at a constant speed, and the magnetic powder clutch (3) applies a load to the left half shaft (22); S3, the differential lock (2) is powered off and unlocked, and a speed difference is formed between the left half shaft (22) and the right half shaft (23), and the operation is performed for a preset time; S4, the differential lock (2) is powered on and locked, and the left half shaft (22) and the right half shaft (23) rotate synchronously for a preset time; S5, repeat steps S3 and S4.

10. A differential lock (2) locking function test method according to claim 9, characterized in that: The process of mode 2 is as follows: T1, mode selection, switch SB6 is closed, and mode 2 is selected for testing; T2, the magnetic powder clutch (3) applies a load to the left half shaft (22); T3, the differential lock (2) is powered on and locked, the left half shaft (22) and the right half shaft (23) rotate synchronously, and the speed of the variable frequency motor (4) increases to a predetermined test speed and runs for a preset time; T4, the differential is powered off and unlocked, a speed difference is generated between the left half shaft (22) and the right half shaft (23), and the operation is performed for a preset time; T5, the variable frequency motor (4) is powered off, and the speed of the variable frequency motor (4) drops to zero; T6, repeat steps T3 to T5.

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