Gearbox testing device and testing method

Abstract

The invention discloses a gearbox testing device and a gearbox testing method, and relates to the field of parking mechanism detection, the gearbox testing device comprises a driving unit which comprises a driving motor used for providing rotation power for a gearbox to be tested and a motor controller used for controlling and monitoring the rotation state of the driving motor; the sensing unit is used for monitoring the rotating speed of an output shaft of the gearbox to be detected and the gear state of a parking mechanism in the gearbox to be detected; the main controller is used for driving the gearbox to be tested to execute P gear switching operation and judging the gear shifting execution process and result of a parking mechanism in the gearbox to be tested according to the monitoring data of the sensing unit after the gearbox to be tested is switched to the P gear. When the P gear is mistakenly touched at a high speed, the conditions that parking is not allowed and the P gear is changed during conventional parking are simulated, and the parking performance detection comprehensiveness of the gearbox is improved.

Description

Technical Field

[0001] The present application relates to the field of parking mechanism detection, and in particular to a gearbox testing device and a testing method. Background Art

[0002] Currently, all passenger car gearboxes are equipped with a P-lock system, which locks the transmission shaft of the gearbox when parking. The gearbox P-lock system refers to a set of P-lock parking actuators (P-lock parking actuators generally include parking gears and parking pawls) that are directly or indirectly connected to the output shaft and integrated inside the gearbox. Its function is to mechanically lock the transmission shaft and prohibit the transmission shaft from rotating, thereby parking the entire vehicle and preventing the vehicle from sliding down a slope.

[0003] However, if the driver accidentally touches the P gear while driving, if the vehicle speed is too high, the P gear will be locked, causing the gearbox to bear a huge mechanical impact, and even damage the power system, posing a danger to the driver and passengers; if the vehicle is not stopped at the end of the parking process, the vehicle still has an extremely low speed, the driver's P gear shift fails, and the gearbox cannot be mechanically self-locked. The existing P gear system offline testing generally only involves slope conditions and vehicle stationary conditions, missing the situation where the P gear does not allow parking at high speed, resulting in insufficient evaluation of the parking mechanism, and there may be safety hazards of failure. Summary of the invention

[0004] The present application provides a gearbox testing device and a testing method, which can solve the technical problems existing in the prior art that the traditional gearbox P gear system offline detection generally only involves slope conditions and vehicle static conditions, and misses the situation that the P gear does not allow parking at high speed, resulting in insufficient evaluation of the gearbox parking performance and possible safety hazards.

[0005] In a first aspect, the present application provides a gearbox testing device for testing a gearbox provided with a parking mechanism, the gearbox testing device comprising:

[0006] A drive unit, comprising a drive motor for providing rotational power to the gearbox to be tested, and a motor controller for controlling and monitoring the rotational state of the drive motor;

[0007] A sensing unit, which is used to monitor the output shaft speed of the gearbox to be tested and the gear position status of the parking mechanism in the gearbox to be tested;

[0008] The main controller is used to drive the gearbox to be tested to perform the P gear shift operation, and after the gearbox to be tested is switched to the P gear, the shift execution process and results of the parking mechanism in the gearbox to be tested are judged according to the monitoring data of the sensing unit.

[0009] In combination with the first aspect, in one implementation, the sensing unit includes a gearbox speed sensor electrically connected to the gearbox to be tested and a shift state sensing device electrically connected to a parking mechanism in the gearbox to be tested.

[0010] In one embodiment, the gear shift state sensing device includes a gear position sensor and a timer.

[0011] In one embodiment, the main controller includes a host computer for collecting data, monitoring the experimental process and alarming abnormal conditions, and a test bench control unit for performing a P gear switching operation on the gearbox to be tested.

[0012] In one embodiment, the gantry control unit includes a control end and an execution end, and the execution end includes a gantry robot arm.

[0013] In a second aspect, an embodiment of the present application provides a gearbox testing method, which is implemented based on the above-mentioned gearbox testing device. The gearbox testing method includes:

[0014] The input shaft of the gearbox to be tested is driven to rotate, and the gearbox to be tested is controlled to perform a P gear shift operation, so that the pawl of the parking mechanism in the gearbox to be tested is engaged with the ratchet wheel, locking the output shaft of the gearbox to be tested;

[0015] Obtain the engagement speed of the output shaft of the gearbox to be tested when the pawl is engaged with the ratchet wheel, and determine whether the engagement speed is within a preset speed range:

[0016] If so, the gear position of the parking mechanism and the parking time are obtained to compare with the preset parameters, and based on the comparison result, the experiment is terminated or the evaluation result of the gear shifting process and result is output.

[0017] If not, an abnormality is indicated and the experiment ends;

[0018] In combination with the second aspect, in one implementation, the driving the input shaft of the gearbox to be tested to rotate and controlling the gearbox to be tested to perform a P gear shift operation so that a pawl of a parking mechanism in the gearbox to be tested is engaged with a ratchet wheel to lock the output shaft of the gearbox to be tested specifically includes:

[0019] Based on the preset vehicle driving condition, the initial speed of the drive motor is determined, and under the scheduling of the main controller, the motor controller controls the drive motor to drive the input shaft of the gearbox to be tested to rotate at the initial speed;

[0020] The main controller controls the gearbox to be tested to perform the P gear shift operation, and the drive motor decelerates at a certain rate until the pawl in the parking mechanism is engaged with the ratchet wheel, and the output shaft of the gearbox to be tested is locked;

[0021] Among them, when the drive motor starts to decelerate until the output shaft of the gearbox to be tested is locked, the sensing unit continuously obtains the rotation speed of the output shaft of the gearbox to be tested.

[0022] In one embodiment, the step of obtaining the engagement speed of the output shaft of the gearbox to be tested when the pawl is engaged with the ratchet wheel and determining whether the engagement speed is within a preset speed range specifically includes:

[0023] Based on the parameter information of the vehicle model pre-assembled with the gearbox to be tested, the speed range allowed for the vehicle model is calculated as the preset speed range;

[0024] Based on the rotation speed of the driving motor and the rotation speed change of the output shaft of the gearbox to be tested when the pawl is engaged with the ratchet wheel, the main controller draws a rotation speed curve of the output shaft of the gearbox to be tested;

[0025] Based on the speed curve, the main controller determines the engagement speed of the output shaft of the gearbox to be tested when the pawl is engaged in the ratchet wheel, and determines whether the engagement speed is within a preset speed range.

[0026] In one implementation, the maximum speed and the minimum speed in the preset speed range are calculated as follows:

[0027] L low =V low *R a *1000 / 2 / π / R / 60.

[0028] L up =V up *R a *1000 / 2 / π / R / 60.

[0029] Among them, L low is the lowest speed in the preset speed range, L up is the maximum speed in the preset speed range, V low is the minimum speed required for the vehicle, V up is the maximum speed required by the vehicle, R a is the speed ratio from the power shaft to the output shaft, and R is the static radius of the vehicle tire.

[0030] In one embodiment, the obtaining of the gear position of the parking mechanism and the parking time for comparison with preset parameters, and ending the experiment or outputting the evaluation results of the shifting process and results based on the comparison results, specifically includes:

[0031] After the P gear switching operation is completed, a reasonable position of the parking mechanism gear is set, and based on the initial speed of the drive motor, a reasonable parking time is set, wherein the reasonable position is that the gear lever of the parking mechanism is in the P gear, and the reasonable parking time is the time allowed for the drive motor to start decelerating until the pawl is engaged with the ratchet wheel at different initial speeds;

[0032] The sensing unit obtains the gear position of the parking mechanism and the parking time, and transmits the sensing value to the main controller, which determines:

[0033] When the gear position of the parking mechanism is not in a reasonable position, the gear shift is judged to have failed, an abnormality is indicated, and the experiment is terminated;

[0034] When the gear position of the parking mechanism is at a reasonable position, it is determined whether the parking time is within the reasonable parking time. If so, the gear shift is determined to be successful, and the gear shift execution process and results of the parking mechanism are judged and the judgment result is output. If not, the gear shift is determined to be a failure, an abnormality is prompted and the experiment ends.

[0035] The beneficial effects brought by the technical solution provided in the embodiments of the present application include:

[0036] By setting different initial exclusive drive motors and simulating the detection of the locking process of the transmission parking mechanism under different driving conditions, the vehicle power parking system detection is realized, the effectiveness of the parking mechanism is fully detected, and safety problems are prevented. The overall structure is simple to operate and can be applied to the testing of all transmissions equipped with parking mechanisms. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0038] Figure 1 A schematic diagram of the structure of a parking mechanism testing device provided in this application;

[0039] Figure 2 A flow chart of a parking mechanism testing method provided in this application;

[0040] Figure 3 A flow chart of a method for judging the shifting execution process and results of a parking mechanism in a parking mechanism testing method provided in the present application.

[0041] In the figure: 1. drive motor; 2. motor controller; 3. main controller; 301. host computer; 302. test bench control unit; 4. gearbox speed sensor; 5. gear shift state sensing device; 6. clutch; 7. gearbox to be tested; 8. parking mechanism. DETAILED DESCRIPTION

[0042] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0043] On the first aspect, the embodiments of the present application provide a transmission testing device, which can solve the technical problem that the traditional transmission P gear system offline detection in the prior art generally only involves slope conditions and vehicle stationary conditions, and lacks the situation where P gear does not allow parking at high speed, resulting in insufficient evaluation of the transmission's parking performance and possible safety hazards.

[0044] Figure 1 A schematic diagram of the parking mechanism testing device provided in this application is shown in FIG. Figure 1 As shown, the parking mechanism testing device in this application includes:

[0045] A drive unit, comprising a drive motor 1 for providing rotational power to the gearbox 7 to be tested, and a motor controller 2 for controlling and monitoring the rotational state of the drive motor 1;

[0046] A sensing unit, which is used to monitor the output shaft speed of the gearbox 7 to be tested and the gear position state of the parking mechanism 8 in the gearbox 7 to be tested;

[0047] The main controller 3 is used to drive the gearbox 7 to be tested to execute the P gear shift operation, and to judge the gear shift execution process and results of the parking mechanism 8 in the gearbox 7 to be tested according to the monitoring data of the sensing unit after the gearbox 7 to be tested is switched to the P gear.

[0048] The gearbox generally includes an input shaft, an output shaft, a parking mechanism 8 and a clutch 6, among which the clutch 6 is located between the input shaft and the output shaft. The parking mechanism 8 is usually composed of a ratchet and a pawl. The ratchet refers to a mechanical device composed of a number of racks, usually consisting of a circular gear with a small and flat friction surface fixed on it. The parking pawl is a "metal arm" rigidly connected to the gearbox housing, and its fixed position is immovable. When switched to the P gear state, the pawl will combine with the parking ratchet to lock the output shaft of the gearbox to prevent the vehicle from sliding or moving.

[0049] In the assembled working condition, the output end of the drive motor 1 in the present application is connected to the input shaft of the gearbox 7 to be tested, the motor controller 2 is electrically connected to the drive motor 1, and the motor controller 2 is dispatched by the main controller 3 to control the drive motor 1 to drive the input shaft of the gearbox 7 to be tested to rotate at a preset initial speed. A CAN bus interface is provided between the motor controller 2, the sensing unit and the main controller 3, and a loop is formed through the CAN bus electrical connection.

[0050] Furthermore, the sensing unit includes a gearbox speed sensor 4 electrically connected to the gearbox 7 to be tested and a gear shift state sensing device 5 electrically connected to the parking mechanism 8 in the gearbox 7 to be tested. The gearbox speed sensor 4 is arranged on the output shaft of the gearbox 7 to be tested, and can sense the speed of the output shaft of the gearbox 7 to be tested during the entire experimental process. The gear shift state sensing device 5 includes a gear position sensor and a timer. The gear position sensor is arranged on the parking mechanism 8 in the gearbox 7 to be tested, and is used to sense the gear position after the gear shift is completed. The timer is used to obtain the time used for parking, and the position can be freely changed according to actual conditions. No specific restrictions are made in this application.

[0051] Furthermore, the main controller 3 includes a host computer 301 for collecting data, monitoring the experimental process and alarming abnormal conditions, and a test bench control unit 302 for performing a P gear switching operation on the gearbox 7 to be tested.

[0052] Specifically, the host computer 301 is also used to realize the collection and storage of test data, the notification of test status, the alarm of abnormal status, etc.; it can also realize the selection, startup and shutdown of the test process; the test bench control unit 302 is the core control system, and is provided with the following functions: calculation of speed ratio, control instructions for P gear action, automatic cycle test, system protection, etc. The test cycle is selected through the host computer 301, and the tester starts or stops the test by operating the control switch (start test switch, stop test switch, P gear switch, manual mode switch, automatic mode switch, etc.). The host computer 301 is provided with a stop test instruction activation module. When the module is activated, no matter which sub-state the program is running in this program block, it must immediately exit this program block.

[0053] In one embodiment of the present application, the test bench control unit 302 includes a control end and an execution end. The execution end includes a test bench robotic arm. The test bench robotic arm is located at the gearbox 7 to be tested. The control end accepts the scheduling of the host computer 301 and controls the test bench robotic arm to perform the gear shifting action. At the same time, the test bench robotic arm will transmit the progress status, gear shifting angle, etc. to the test bench control unit 302, and the gear position sensor will feedback the progress status, P gear position and other information to the test bench control unit 302 through the CAN bus.

[0054] During the experiment, the drive motor 1 first rotates at a certain speed, and then the test bench control unit 302 outputs a P gear switching operation instruction. The test bench mechanical arm in the test bench control unit 302 performs the P gear switching operation on the gearbox 7 to be tested. The pawl in the gearbox 7 to be tested will combine with the parking ratchet to lock the output shaft of the gearbox 7 to be tested. During this period, the sensing unit will continuously obtain the rotational speed of the output shaft of the gearbox 7 to be tested, as well as the gear position of the parking mechanism 8 after the P gear switching operation is completed, and the parking time during the whole process, and transmit the obtained values ​​to the test bench control unit 302. The test bench control unit 302 comprehensively evaluates the rationality of the P gear switching operation process of the gearbox 7 to be tested, and finally outputs the evaluation result to complete the test of the gearbox 7 to be tested.

[0055] In a second aspect, an embodiment of the present application provides a gearbox testing method, which is implemented based on the above-mentioned gearbox testing device. Specifically, Figure 2 A flow chart of a parking mechanism testing method provided in this application is shown as follows: Figure 2 As shown, the gearbox testing method specifically includes:

[0056] S1: driving the input shaft of the gearbox 7 to be tested to rotate, and controlling the gearbox 7 to be tested to perform the P gear shift operation, so that the pawl of the parking mechanism 8 in the gearbox 7 to be tested is engaged with the ratchet wheel, locking the output shaft of the gearbox 7 to be tested, and then going to S2;

[0057] S2: Obtain the engagement speed of the output shaft of the gearbox 7 to be tested when the pawl is engaged with the ratchet wheel, and determine whether the engagement speed is within a preset speed range. If so, go to S3; if not, go to S4;

[0058] S3: Obtain the gear position of the parking mechanism 8 and the parking time to compare with the preset parameters, and based on the comparison result, end the experiment or output the evaluation result of the gear shifting process and result.

[0059] S4: prompt abnormality and end the experiment;

[0060] At the beginning of the test, the drive motor 1 is controlled to be in a rotating state to simulate the vehicle driving condition, and then the gearbox 7 to be tested is controlled to perform the P gear switching operation. When the drive motor 1 starts to decelerate and the pawl is engaged with the ratchet, the output shaft of the gearbox 7 to be tested is locked and the speed drops to 0, so as to complete the entire process of triggering the P gear during vehicle driving.

[0061] During this period, the sensing unit continuously obtains the rotational speed of the output shaft of the gearbox 7 to be tested, the gear position of the parking mechanism 8 after the P gear switching operation is completed, and the parking time during the whole process, and compares the above-mentioned parameters with the preset parameter range to evaluate the rationality of the whole parking process. If during the experiment, the obtained parameters exceed the preset parameters, the main controller 3 prompts an abnormality and controls the end of the test to facilitate the staff to find the cause. If during the experiment, the obtained parameters are always within the preset parameters, the experiment ends according to the normal process, and the main controller 3 outputs the evaluation results for the convenience of the staff to view.

[0062] Specifically, step S1 specifically includes:

[0063] S101: Based on a preset vehicle driving condition, the initial speed of the drive motor 1 is determined, and under the dispatch of the main controller 3, the motor controller 2 controls the drive motor 1 to drive the input shaft of the gearbox 7 to be tested to rotate at the initial speed;

[0064] First, the system is powered on and initialized, and the test bench control unit 302 reads the parameters set by the host computer 301, such as the test cycle, input speed, wheel parameters, driving mode, etc., and then the experimental phase begins.

[0065] After the initial speed is set in the main controller 3, the motor controller 2 receives the set parameters of the main controller 3 and drives the drive motor 1 to rotate. The gearbox testing method in the present application can cover a variety of working conditions of the vehicle in high-speed driving, low-speed driving and stationary state, which can be achieved by setting the initial speed of the drive motor 1. That is, if the vehicle stationary state needs to be tested, the drive motor 1 is controlled to rotate at a lower speed or completely stationary. Similarly, if the vehicle high-speed driving and low-speed driving need to be tested, the initial speed of the drive motor 1 is controlled to increase. Under the same working conditions, different models have different engine types, and the initial speed of the drive motor 1 may also vary. Therefore, the initial speed of the drive motor 1 is flexibly determined according to experimental requirements. In the present application, no specific restrictions are made.

[0066] S102: the main controller 3 controls the gearbox 7 to be tested to perform a P gear shift operation, and the drive motor 1 decelerates at a certain rate until the pawl in the parking mechanism 8 is engaged with the ratchet wheel, and the output shaft of the gearbox 7 to be tested is locked;

[0067] When the speeds of the drive motor 1 and the gearbox 7 to be tested are stable, the main controller 3 performs a P gear switching operation on the gearbox 7 to be tested. At this time, the parking mechanism 8 in the gearbox 7 to be tested starts to act, so that the speed of the drive motor 1 gradually slows down. Until the drive motor 1 drops to a certain speed, the pawl in the parking mechanism 8 engages with the ratchet wheel, and the output shaft of the gearbox 7 to be tested is locked. At this time, the speed of the output shaft of the gearbox 7 to be tested drops to 0.

[0068] During the whole process from the start of the parking mechanism 8 to the completion of parking, the sensing unit continuously acquires the rotation speed of the output shaft of the gearbox 7 to be tested, and the main controller 3 receives the acquired value of the sensing unit.

[0069] Furthermore, step S2 specifically includes:

[0070] S201: Based on the parameter information of the vehicle model pre-assembled with the gearbox 7 to be tested, the speed range allowed for the vehicle model is calculated as the preset speed range;

[0071] S202: Based on the rotation speed of the driving motor 1 and the rotation speed change of the output shaft of the gearbox 7 to be tested during the process of the pawl being engaged with the ratchet wheel, the main controller 3 draws a rotation speed curve of the output shaft of the gearbox 7 to be tested;

[0072] S203: Based on the speed curve, the main controller 3 determines the engagement speed of the output shaft of the gearbox 7 to be tested when the pawl is engaged in the ratchet wheel, and determines whether the engagement speed is within a preset speed range.

[0073] Each vehicle model is affected by many factors, and the parking performance of the gearbox with the same configuration installed in different models is also inconsistent. Therefore, before the experiment begins, the preset speed range of the vehicle model is determined according to the vehicle model pre-installed with the gearbox 7 to be tested. Subsequently, based on the change in the speed of the output shaft of the gearbox 7 to be tested caused by the process of the pawl being engaged in the ratchet, the speed curve of the output shaft of the gearbox 7 to be tested is drawn. The speed curve is one of the important indicators reflecting the performance of the gearbox. It shows how the speed of the output shaft of the gearbox 7 to be tested changes under different working conditions. By analyzing this curve, we can understand the gear shifting performance, power transmission efficiency and adaptability of the gearbox under different working conditions.

[0074] During the operation of the gearbox 7 to be tested, the speed of the output shaft of the gearbox 7 to be tested will change according to the selected gear and the engine speed. This change is usually smooth, but in some cases, such as during the gear shifting process, a sharp change in speed may occur. This change may appear as an obvious "corner" or "inflection point" on the speed curve. Therefore, the engagement speed of the output shaft of the gearbox 7 to be tested can be clearly and accurately obtained through the position of the corner of the speed curve.

[0075] The main controller 3 compares the engagement speed of the output shaft of the gearbox 7 to be tested with the preset speed range. If the engagement speed is within the speed range, it means that at the current initial speed, the gearbox 7 to be tested can meet the parking function, and then the gear position of the parking mechanism 8 and the parking time can be compared. If the engagement speed is outside the speed range, the experiment is stopped and the staff investigates the cause. At the same time, it is also to prevent the engagement speed of the gearbox output shaft from being too high, which may cause damage to the parts of the parking mechanism 8.

[0076] Furthermore, for the maximum speed and the minimum speed in the preset speed range, the calculation method is:

[0077] L low =V low *R a *1000 / 2 / π / R / 60.

[0078] L up =V up *R a *1000 / 2 / π / R / 60.

[0079] Among them, L low is the lowest speed in the preset speed range, L up is the maximum speed in the preset speed range, V low is the minimum speed required for the vehicle, V up is the maximum speed required by the vehicle, R a is the speed ratio from the power shaft to the output shaft, and R is the static radius of the vehicle tire.

[0080] Furthermore, Figure 3 This is a flow chart of a method for judging the shifting execution process and results of a parking mechanism in a parking mechanism testing method provided in this application, such as Figure 3 As shown, step S3 specifically includes:

[0081] S301: after the P gear switching operation is completed, a reasonable position of the parking mechanism 8 is set, and based on the initial speed of the driving motor 1, a reasonable parking time is set, wherein the reasonable position is that the gear lever of the parking mechanism 8 is at the P gear, and the reasonable parking time is the time allowed for the driving motor 1 to start decelerating until the pawl is engaged with the ratchet wheel at different initial speeds, and then go to S302;

[0082] S302: the sensing unit obtains the gear position of the parking mechanism 8 and the parking time, and transmits the sensing value to the main controller 3, the main controller 3 determines whether the gear position of the parking mechanism 8 is at a reasonable position, if not, then go to S303, if yes, then go to S304;

[0083] S303: determining that the gear shift fails, indicating an abnormality and terminating the experiment;

[0084] S304: Determine whether the parking time is within the reasonable parking time, if so, go to S305, if not, go to S306;

[0085] S305: Determine whether the gear shift is successful, evaluate the gear shift execution process and result of the parking mechanism 8, and output the evaluation result;

[0086] S306: Determine that the gear shift fails, indicate an abnormality, and end the experiment.

[0087] When evaluating the parking function of the gearbox 7 to be tested, in addition to the speed, the gear position after parking and the time used for parking must also be considered. Therefore, the sensing unit will sense the gear position of the parking mechanism 8 and the time used for parking after parking is completed, and transmit the sensing value to the main controller 3 for comparison and judgment with the preset reasonable position and reasonable parking time, and based on the judgment result, choose to prompt the abnormality and end the experiment to facilitate the staff to investigate, or the P gear shift operation is successful, the experimental process ends normally, and the main controller 3 outputs the judgment result of the normal function of the gearbox 7 to be tested and all the data of the gear shifting process.

[0088] In this step, the gear position monitoring of the parking mechanism 8 takes precedence over the parking time to facilitate troubleshooting, that is, first determine that the gear position of the parking mechanism 8 is at a reasonable position, and then compare the parking time. Because the gear position is fully confirmed, if the parking time exceeds the limit, the most likely possibility is that the parking mechanism 8 inside the reduction box 7 to be tested is damaged, resulting in the failure of the parking function, or the parking mechanism 8 is subjected to the parking torque, and the reaction force causes the actuator to reset. These are all situations that the P gear system does not allow, and the system must stop the test for fault analysis.

[0089] It should be noted here that, consistent with the above reasons, the parking performance of the same configuration of gearboxes installed in different models is also inconsistent. Therefore, the reasonable parking time is not specifically restricted in this application and can be determined according to different models.

[0090] After a single experiment is completed, if the initial setting is to perform a cyclic test, the system will return to step S1 to repeat the test.

[0091] In the description of the present application, it should be noted that the terms "upper", "lower", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. Unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.

[0092] It should be noted that, in this application, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0093] The above description is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest range consistent with the principles and novel features applied for herein.

Claims

1. A gearbox testing device for testing a gearbox provided with a parking mechanism (8), characterized in that: The gearbox testing device comprises: A drive unit, comprising a drive motor (1) for providing rotational power to a gearbox (7) to be tested, and a motor controller (2) for controlling and monitoring the rotational state of the drive motor (1); A sensing unit, which is used to monitor the output shaft speed of the gearbox (7) to be tested, and the gear position state of the parking mechanism (8) in the gearbox (7) to be tested; A main controller (3) is used to drive the gearbox to be tested (7) to execute a P gear shift operation, and to judge the gear shift execution process and result of the parking mechanism (8) in the gearbox to be tested (7) according to the monitoring data of the sensing unit after the gearbox to be tested (7) is switched to the P gear.

2. A gearbox testing device as claimed in claim 1, characterized in that: The sensing unit comprises a gearbox speed sensor (4) electrically connected to the gearbox (7) to be tested, and a shift state sensing device (5) electrically connected to a parking mechanism (8) in the gearbox (7) to be tested.

3. A gearbox testing device as claimed in claim 2, characterized in that: The gear shift state sensing device (5) comprises a gear position sensor and a timer.

4. A gearbox testing device as claimed in claim 1, characterized in that: The main controller (3) comprises a host computer (301) for collecting data, monitoring the experimental process and alarming abnormal conditions, and a test bench control unit (302) for performing a P gear switching operation on the gearbox (7) to be tested.

5. A gearbox testing device as claimed in claim 4, characterized in that: The gantry control unit (302) comprises a control end and an execution end, and the execution end comprises a gantry mechanical arm.

6. A gearbox testing method, implemented based on the gearbox testing device according to any one of claims 1 to 5, characterized in that: The gearbox testing method comprises: The input shaft of the gearbox to be tested (7) is driven to rotate, and the gearbox to be tested (7) is controlled to perform a P gear switching operation, so that the pawl of the parking mechanism (8) in the gearbox to be tested (7) is engaged with the ratchet wheel, thereby locking the output shaft of the gearbox to be tested (7); Obtaining the engagement speed of the output shaft of the gearbox (7) to be tested when the pawl is engaged with the ratchet wheel, and determining whether the engagement speed is within a preset speed range: If so, the gear position of the parking mechanism (8) and the parking time are obtained to compare with the preset parameters, and based on the comparison result, the experiment is terminated or the evaluation result of the gear shifting process and result is output. If not, an abnormality is prompted and the experiment ends.

7. A gearbox testing method as claimed in claim 6, characterized in that: The method drives the input shaft of the gearbox (7) to be tested to rotate, and controls the gearbox (7) to be tested to perform a P gear shift operation, so that the pawl of the parking mechanism (8) in the gearbox (7) to be tested is engaged with the ratchet wheel, thereby locking the output shaft of the gearbox (7) to be tested, and specifically includes: Based on a preset vehicle driving condition, an initial rotation speed of the drive motor (1) is determined, and under the control of a main controller (3), the motor controller (2) controls the drive motor (1) to drive the input shaft of the gearbox (7) to be tested to rotate at the initial rotation speed; The main controller (3) controls the gearbox (7) to be tested to perform a P gear switching operation, and the drive motor (1) decelerates at a certain rate until the pawl in the parking mechanism (8) is engaged with the ratchet wheel, and the output shaft of the gearbox (7) to be tested is locked; In the process where the drive motor (1) starts to decelerate until the output shaft of the gearbox (7) to be tested is locked, the sensing unit continuously acquires the rotation speed of the output shaft of the gearbox (7) to be tested.

8. A gearbox testing method as claimed in claim 7, characterized in that: The step of obtaining the engagement speed of the output shaft of the gearbox (7) to be tested when the pawl is engaged with the ratchet wheel and judging whether the engagement speed is within a preset speed range specifically includes: Based on the parameter information of the vehicle model pre-assembled with the gearbox (7) to be tested, the speed range allowed for the vehicle model is calculated and obtained as the preset speed range; Based on the rotation speed of the driving motor (1) and the rotation speed change of the output shaft of the gearbox (7) to be tested when the pawl is engaged with the ratchet wheel, the main controller (3) draws a rotation speed curve of the output shaft of the gearbox (7) to be tested; Based on the speed curve, the main controller (3) determines the engagement speed of the output shaft of the gearbox (7) to be tested when the pawl is engaged with the ratchet wheel, and judges whether the engagement speed is within a preset speed range.

9. A gearbox testing method as claimed in claim 8, characterized in that: For the highest speed and the lowest speed in the preset speed range, the calculation method is: L low =V low *R a *1000 / 2 / π / R / 60. L up =V up *R a *1000 / 2 / π / R / 60. Among them, L low is the lowest speed in the preset speed range, L up is the maximum speed in the preset speed range, V low is the minimum speed required for the vehicle, V up is the maximum speed required by the vehicle, R a is the speed ratio from the power shaft to the output shaft, and R is the static radius of the vehicle tire.

10. A gearbox testing method as claimed in claim 6, characterized in that: The obtaining of the gear position of the parking mechanism (8) and the parking time for comparison with preset parameters, and based on the comparison result, terminating the experiment or outputting the evaluation result of the gear shifting process and result, specifically includes: After the P gear switching operation is completed, a reasonable position of the parking mechanism (8) is set, and based on the initial rotation speed of the drive motor (1), a reasonable parking time is set, wherein the reasonable position is when the gear lever of the parking mechanism (8) is in the P gear, and the reasonable parking time is the time allowed for the drive motor (1) to start decelerating until the pawl is engaged with the ratchet wheel at different initial rotation speeds; The sensing unit obtains the gear position of the parking mechanism (8) and the parking time, and transmits the sensing values ​​to the main controller (3). The main controller (3) determines: When the gear position of the parking mechanism (8) is not at a reasonable position, it is determined that the gear shift has failed, an abnormality is indicated, and the experiment is terminated; When the gear position of the parking mechanism (8) is at a reasonable position, it is determined whether the parking time is within the reasonable parking time. If so, it is determined that the gear shift is successful, and the gear shift execution process and results of the parking mechanism (8) are judged and the judgment result is output. If not, it is determined that the gear shift fails, an abnormality is prompted and the experiment ends.

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