CN115326381A - Gear shifting endurance test device and test method for two-gear reduction gearbox - Google Patents
Gear shifting endurance test device and test method for two-gear reduction gearbox Download PDFInfo
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- CN115326381A CN115326381A CN202210853418.1A CN202210853418A CN115326381A CN 115326381 A CN115326381 A CN 115326381A CN 202210853418 A CN202210853418 A CN 202210853418A CN 115326381 A CN115326381 A CN 115326381A
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- gear
- reduction box
- gear reduction
- shifting
- input shaft
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M13/00—Testing of machine parts
- G01M13/02—Gearings; Transmission mechanisms
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M13/00—Testing of machine parts
- G01M13/02—Gearings; Transmission mechanisms
- G01M13/025—Test-benches with rotational drive means and loading means; Load or drive simulation
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M17/00—Testing of vehicles
- G01M17/007—Wheeled or endless-tracked vehicles
- G01M17/0072—Wheeled or endless-tracked vehicles the wheels of the vehicle co-operating with rotatable rolls
Abstract
The invention relates to the technical field of vehicle verification, and discloses a gear shifting endurance test device for a two-gear reduction box, which comprises a test bench, wherein the two-gear reduction box is arranged on the test bench, a gear shifting system is arranged on an input shaft of the two-gear reduction box, a motor shaft of the test bench provides power for an output shaft of the two-gear reduction box so as to drive the input shaft of the two-gear reduction box to rotate, and a rotating speed detection device and a motor rotating inertia simulation device are arranged on the input shaft. The invention also discloses a test method of the gear shifting endurance test device of the two-gear reduction box. The two-gear reduction box gear shifting endurance test device and the test method thereof simulate the inertia of the electric automobile motor, reduce the test complexity and the test cost, and avoid the failure which is not in accordance with the actual working condition and is caused by excessive acceleration.
Description
Technical Field
The invention relates to the technical field of vehicle verification, in particular to a gear shifting endurance test device and a gear shifting endurance test method for a two-gear reduction box.
Background
Electric automobile wide application single-gear reducing gear box at present, but on high-end motorcycle type, in order to further promote electric automobile's dynamic nature and economic nature, the design and the use of two fender reducing gear boxes are also increasing day by day. Two keep off the reducing gear box and increased the function of shifting relative single-gear reducing gear box, but compare in traditional multi-gear gearbox, because often can carry out the motor speed governing before shifting for the condition of shifting is loose a lot compared with traditional multi-gear gearbox. The gear shifting is used as one of the core functions of the two-gear reduction box, and the verification of the gear shifting endurance test is very important.
At present, a plurality of verification methods of shift endurance tests, such as a QC/T568 automobile mechanical transmission assembly bench test method, are available for the traditional multi-gear transmission. But no relevant standard is used as reference for the two-gear reduction gearbox of the electric automobile.
Different from the traditional multi-gear gearbox, the two-gear reduction box of the electric automobile is directly connected with a motor. When the bench is used for implementing the gear shifting endurance test of the two-gear reduction box, generally, in order to save test cost and improve test efficiency, a motor test is not always assembled, so that the loss of motor inertia influence factors can be brought, and the loss of input rotating speed signals of the reduction box is avoided.
Therefore, it is necessary to develop a bench test apparatus that is easy to implement for the shift endurance test apparatus of the two-speed reduction gear box. Aiming at the gear shifting endurance test method of the two-gear reduction box, a more reasonable gear shifting endurance test method is provided according to the actual gear shifting characteristics of the electric automobile.
Disclosure of Invention
Aiming at the defects of the technology, the invention provides the two-gear reduction box gear shifting endurance test device and the test method thereof, which are used for simulating the inertia of the electric automobile motor, reducing the test complexity and the test cost and avoiding the failure which is not in accordance with the actual working condition and is caused by excessive acceleration.
In order to achieve the purpose, the gear shifting endurance test device for the two-gear reduction gearbox comprises a test bench, the two-gear reduction gearbox is installed on the test bench, a gear shifting system is arranged on an input shaft of the two-gear reduction gearbox, a motor shaft of the test bench provides power for an output shaft of the two-gear reduction gearbox to further drive the input shaft of the two-gear reduction gearbox to rotate, and a rotating speed detection device and a motor rotating inertia simulation device are arranged on the input shaft.
Preferably, the rotating speed detecting device comprises a gear sleeved on the input shaft and a rotating speed detector arranged on the two-gear reduction box and used for detecting the rotating speed of the gear, and the gear is limited by a first spline on the input shaft and driven by the input shaft and the first spline to rotate.
Preferably, the gear is provided with an internal bore which is an interference fit with a first spline on the input shaft.
Preferably, the number of teeth Z of said gear gear ≤f TSS *60/n max Wherein, f TSS Is the maximum frequency, n, of the revolution detector max Is the maximum rotational speed of the input shaft, in units: the rpm is given.
Preferably, the pitch of the gear crests is greater than the distance between the sensing units on the rotation speed detector.
Preferably, the distance between the rotation speed detector and the gear satisfies the detection distance of the rotation speed detector.
Preferably, the motor rotational inertia simulation device comprises an inertia disc sleeved on the input shaft, the rotational inertia value of the inertia disc is equal to the rotational inertia value of the motor of the electric vehicle, and the inertia disc is limited by a second spline on the input shaft and is driven by the input shaft and the second spline to rotate.
Preferably, the two-gear speed reduction box further comprises an end cover mounted on the two-gear speed reduction box shell, a bearing is assembled on the end cover, and the inertia disc is mounted on the bearing.
Preferably, the end cover is further provided with a gasket for abutting against the bearing.
A test method of the two-gear reduction box gear shifting endurance test device comprises the following steps:
a) And (3) a small rotating speed difference gear shifting working condition: setting the speed regulation precision of the electric automobile motor during gear shifting to be +/-N max The rotating speed of the motor shaft of the test bed is N, unit: rpm, N = delta N/(i 1-i 2), where delta N is the upshift speed difference, in which case, delta N = N max I1 is the total speed ratio of the first gear, i2 is the total speed ratio of the second gear, and the rotating speed N = N of the motor shaft of the test bench is kept max (i 1-i 2), wherein the two-gear reduction box is lifted from the first gear to the second gear, and then is lowered from the second gear to the first gear for one cycle, and the cycle is performed for C1 time;
b) The medium speed difference gear shifting working condition is as follows: at this time, Δ n = Δ w × 60/2 pi, Δ w is an angular velocity difference of the input shaft of the two-speed reduction gearbox before and after shifting, and a unit: rad/s,. DELTA.w = V Slippage *1000 × 2/d, d is the average friction diameter of the synchronizer cone of the two-gear reduction box, unit: mm, V Slipping of the ball The unit of the slip linear speed between the conical surfaces of the synchronizer of the two-gear reduction box is as follows: m/s, and the maximum linear speed of the slip capable of being borne by the synchronizer of the two-gear reduction box is Vmax Slippage ，V Slipping of the ball ＝αVmax Slippage Alpha is a slippage verification coefficient, the value range in the medium rotating speed difference gear shifting working condition is 0.4-0.6, and the rotating speed N = alpha Vmax of the motor shaft of the test bed is kept Slippage *1000 x 2/d 60/2 pi/(i 1-i 2), wherein the two-gear reduction box is lifted from the first gear to the second gear, and then is lowered from the second gear to the first gear to form a cycle, and the cycle is performed for C2 times;
c) Integrally circulating the step A) and the step B) for D times;
d) After the circulation is finished, checking the two-gear reduction box;
the total friction work of the synchronizer of the two-gear reduction box in the test needs to be covered by the total friction work W of the synchronizer of the two-gear reduction box in the specified service life Target Namely:
(2*E1*C1+2*E2*C2)*D≥β*W target
In the formula, beta is a verification coefficient, E1 is single-cycle friction work of upshifting or downshifting under a small rotating speed difference shifting working condition, E2 is single-cycle friction work of upshifting or downshifting under a medium rotating speed difference shifting working condition, E = 0.5J (2 pi Δ N/60) ^2, in the formula, J is the sum of rotating inertia values of a two-gear reduction box and a motor rotating inertia simulation device, and Δ N = N max The obtained value is E1, delta n = alpha Vmax Slippage * The result is E2 at 1000 x 2/d 60/2 pi.
Compared with the prior art, the invention has the following advantages:
1. the speed detection function of the input shaft is added, so that the problem that the speed signal of the input shaft is lost when the rack provides the speed from the output end and the motor of the vehicle without the electric motor is used for a gear shifting endurance test is solved;
2. the motor rotational inertia simulation device is adopted to replace an electric automobile motor, an electric drive assembly (the motor and a reduction gearbox) is not required to be adopted for a gear shifting endurance test, and the test complexity and the test cost are reduced;
3. the invention adopts the low and medium speed difference to carry out the gear-shifting endurance test, thereby not only verifying the gear-shifting function of the reduction gearbox under the conventional speed difference, but also accelerating the gear-shifting endurance test, reducing the test period and the cost, canceling the gear-shifting working condition with high speed difference existing in the traditional gearbox, and avoiding the failure generation which is not in accordance with the actual working condition and is caused by excessive acceleration.
Drawings
Fig. 1 is a schematic structural view of a two-gear reduction gearbox in the gear shifting endurance test apparatus of the two-gear reduction gearbox of the present invention.
The components in the figures are numbered as follows:
the device comprises an input shaft 1, a gear 2, a rotating speed detector 3, an inertia disc 4, an end cover 5 and a bearing 6.
Detailed Description
The invention is described in further detail below with reference to the figures and the specific embodiments.
As shown in figure 1, the gear shifting endurance test device of the two-gear reduction box comprises a test bench, wherein the two-gear reduction box is installed on the test bench, a gear shifting system is arranged on an input shaft of the two-gear reduction box, a motor shaft of the test bench provides power for an output shaft of the two-gear reduction box so as to drive an input shaft 1 of the two-gear reduction box to rotate, and a rotating speed detection device and a motor rotating inertia simulation device are arranged on the input shaft 1.
Wherein, rotational speed detection device is including the cover put install at the gear 2 of input shaft 1 and install the rotational speed detector 3 of surveying the 2 rotational speeds of gear on two grades of reducing gear boxes, and gear 2 is spacing through the first spline on the input shaft 1, rotates under the drive of input shaft 1 and first spline, gear 2 be equipped with the input shaft 1 on first spline interference fit's hole.
In the present embodiment, the number of teeth Z of the gear gear ≤f TSS *60/n max Wherein f is TSS Maximum frequency, n, of the revolution detector max Maximum speed of the input shaft, unit: and (3) rpm, the tooth top distance of the gear is greater than the distance between the sensing units on the rotating speed detector, and the distance between the rotating speed detector and the gear meets the detection distance of the rotating speed detector.
In addition, the motor rotational inertia simulation device comprises an inertia disc 4 which is sleeved on the input shaft 1, the rotational inertia value of the inertia disc 4 is equal to that of the motor of the electric automobile, and the inertia disc 4 is limited by a second spline on the input shaft 1 and rotates under the driving of the input shaft 1 and the second spline.
Meanwhile, the end cover 5 is installed on the shell of the two-gear speed reduction box, the bearing 6 is installed on the end cover 5, the bearing 6 is provided with lubricating grease, the inertia disc 4 is installed on the bearing 6, namely one end of the inertia disc 4 is installed on the bearing 6, the other end of the inertia disc 4 is installed on the input shaft 1, and the end cover 5 is further provided with a gasket which abuts against the bearing 6 to prevent the inertia disc 4 from axially moving.
In this embodiment, the input shaft 1 of the two-speed reduction gearbox is provided with the first spline and the second spline, and in other embodiments, if the input shaft 1 is not provided with the splines, the splines can be processed to be provided with the first spline and the second spline.
The test method of the gear shifting endurance test device of the two-gear reduction box comprises the following steps of:
a) And (3) a small speed difference gear shifting working condition: setting the speed regulation precision of the electric automobile motor during gear shifting to be +/-N max The rotating speed of the motor shaft of the test bed is N, unit: rpm, N = delta N/(i 1-i 2), where delta N is the upshift speed difference, in which case, delta N = N max I1 is the total speed ratio of the first gear, i2 is the total speed ratio of the second gear, and the rotating speed N = N of the motor shaft of the test bench is kept max (i 1-i 2), the two-gear reduction box is lifted from the first gear to the second gear, and then is lowered from the second gear to the first gear for one cycle, and the cycle is carried out for C1 times;
b) The medium speed difference gear shifting working condition is as follows: at this time, Δ n = Δ w × 60/2 pi, Δ w is an angular velocity difference of the input shaft 1 of the two-speed reduction gearbox before and after shifting, unit: rad/s, Δ w = V Slippage *1000 x 2/d, d is the average friction diameter of the synchronizer conical surface of the two-gear reduction box, unit: mm, V Slippage The unit of the slip linear speed between the conical surfaces of the synchronizer of the two-gear reduction box is as follows: m/s, and the maximum linear speed of slip which can be borne by a synchronizer of the two-gear reduction box is Vmax Slipping of the ball ，V Slippage ＝αVmax Slippage Alpha is a slippage verification coefficient, the value range in the medium rotating speed difference gear shifting working condition is 0.4-0.6, in the embodiment, 0.5, and the rotating speed N = alpha Vmax of the motor shaft of the test bed is kept Slippage *1000 x 2/d 60/2 pi/(i 1-i 2), wherein the two-gear reduction gearbox is lifted from the first gear to the second gear, and then is lowered from the second gear to the first gear for one cycle, and the cycle is carried out for C2 times;
c) Integrally circulating the step A) and the step B) for D times;
d) After the circulation is finished, checking the two-gear reduction box;
wherein, the total friction work of the synchronizer of the two-gear reduction box in the test needs to cover the total friction work W of the synchronizer of the two-gear reduction box in the specified service life Target Namely:
(2*E1*C1+2*E2*C2)*D≥β*W target
In the formula, beta is a verification coefficient and is set according to the reliability requirement, E1 is single-time cyclic friction work of upshift or downshift under the small speed difference shifting working condition, E2 is single-time cyclic friction work of upshift or downshift under the medium speed difference shifting working condition, E = 0.5J (2 pi delta N/60) ^2, in the formula, J is the sum of the rotational inertia values of the two-gear reduction box and the motor rotational inertia simulation device, and delta N = N max The obtained result is E1, Δ n = α Vmax Slippage * The result is E2 when the value is 1000X 2/d 60/2 pi.
In this embodiment, a cycle parameter of the small speed difference shift condition and the medium speed difference shift condition is as follows:
the overall cycle number was then 5.
In this embodiment, shift after the electric automobile motor speed governing, because the motor speed governing precision is high, do not have the well rotational speed difference that appears in traditional multi-gear transmission and the operating mode of shifting of high rotational speed difference. However, in order to compress the period of the gear shifting endurance test and improve the test efficiency, the gear shifting speed difference still needs to be increased to accelerate the test, so that the gear shifting endurance test of the two-gear reduction box cancels the high speed difference gear shifting working condition in the traditional multi-gear transmission box, and avoids excessive acceleration to cause a failure mode which is not in line with the actual working condition.
According to the gear-shifting endurance test device and the test method thereof for the two-gear reduction box, the input shaft rotating speed detection function is added, and the problem that the rotating speed signal of the input shaft is lost when the rack provides the rotating speed from the output end and the electric automobile motor is not electrified for performing the gear-shifting endurance test is solved; the motor rotating inertia simulation device is adopted to replace an electric automobile motor, an electric drive assembly (the motor and a reduction gearbox) is not required to be adopted for a gear shifting endurance test, and the test complexity and the test cost are reduced; the invention adopts the low and medium speed difference to carry out the gear-shifting endurance test, thereby not only verifying the gear-shifting function of the reduction gearbox under the conventional speed difference, but also accelerating the gear-shifting endurance test, reducing the test period and the cost, canceling the gear-shifting working condition with high speed difference existing in the traditional gearbox, and avoiding the failure generation which is not in accordance with the actual working condition and is caused by excessive acceleration.
Claims (10)
1. The utility model provides a two keep off reducing gear box endurance test device that shifts, includes test bench, its characterized in that: the test bench is characterized in that the two-gear reduction box is installed on the test bench, a gear shifting system is arranged on an input shaft of the two-gear reduction box, a motor shaft of the test bench provides power for an output shaft of the two-gear reduction box to further drive an input shaft (1) of the two-gear reduction box to rotate, and a rotating speed detection device and a motor rotational inertia simulation device are arranged on the input shaft (1).
2. The two-gear reduction box gear shifting endurance test apparatus of claim 1, wherein: the rotating speed detection device comprises a gear (2) sleeved on the input shaft (1) and a rotating speed detector (3) arranged on the two-gear reduction box and used for detecting the rotating speed of the gear (2), wherein the gear (2) is limited through a first spline on the input shaft (1), and rotates under the driving of the input shaft (1) and the first spline.
3. The two-gear reduction box gear shifting endurance test apparatus of claim 2, wherein: the gear (2) is provided with an inner hole in interference fit with the first spline on the input shaft (1).
4. The two-gear reduction box gear shifting endurance test apparatus of claim 2, wherein: the number of teeth Z of the gear (2) gear ≤f TSS *60/n max Wherein f is TSS Is the maximum frequency, n, of the revolution speed detector (3) max Is the maximum rotational speed of the input shaft (1) in units: rpm.
5. The two-gear reduction box gear shifting endurance test apparatus of claim 2, wherein: the tooth crest distance of the gear (2) is larger than the distance between the sensing units on the rotating speed detector (3).
6. The two-gear reduction box gear shifting endurance test apparatus of claim 2, wherein: the distance between the rotating speed detector (3) and the gear (2) meets the detection distance of the rotating speed detector (3).
7. The two-gear reduction box gear shifting endurance test apparatus of claim 1, wherein: the motor rotational inertia simulation device comprises an inertia disc (4) which is sleeved on the input shaft (1), wherein the rotational inertia value of the inertia disc (4) is equal to the rotational inertia value of a motor of the electric automobile, and the inertia disc (4) is limited by a second spline on the input shaft (1) and rotates under the driving of the input shaft (1) and the second spline.
8. The two-gear reduction box gear shifting endurance test apparatus of claim 7, wherein: the two-gear speed reducer is characterized by further comprising an end cover (5) installed on the shell of the two-gear speed reducer, a bearing (6) is assembled on the end cover (5), and the inertia disc (4) is installed on the bearing (6).
9. The two-gear reduction box gear shifting endurance test apparatus of claim 8, wherein: and the end cover (5) is also provided with a gasket which props against the bearing (6).
10. A test method of the two-gear reduction box gear-shifting endurance test device according to claims 1-9 is characterized in that: the method comprises the following steps:
a) And (3) a small speed difference gear shifting working condition: setting the speed regulation precision of the electric automobile motor during gear shifting to be +/-N max The rotating speed of the motor shaft of the test bed is N, unit: rpm, N = delta N/(i 1-i 2), where delta N is the upshift speed difference, in which case, delta N = N max I1 is the total speed ratio of the first gear, i2 is the total speed ratio of the second gear, and the rotating speed N = N of the motor shaft of the test bench is kept max (i 1-i 2), the two-gear reduction box is lifted from the first gear to the second gear, and then is lowered from the second gear to the first gear for one cycle, and the cycle is C1 times;
b) The medium speed difference gear shifting working condition is as follows: at this time, Δ n = Δ w 60The/2 pi and the delta w are the angular speed difference of the input shaft (1) of the two-gear reduction box before and after gear shifting, and the unit is as follows: rad/s, Δ w = V Slippage *1000 x 2/d, d is the average friction diameter of the synchronizer conical surface of the two-gear reduction gearbox, unit: mm, V Slippage The unit of the slip linear speed between the conical surfaces of the synchronizer of the two-gear reduction box is as follows: m/s, and the maximum linear speed of the slip capable of being borne by the synchronizer of the two-gear reduction box is Vmax Slippage ，V Slipping of the ball ＝αVmax Slippage Alpha is a slippage verification coefficient, the value range in the medium rotating speed difference gear shifting working condition is 0.4-0.6, and the rotating speed N = alpha Vmax of the motor shaft of the test bed is kept Slippage *1000 x 2/d 60/2 pi/(i 1-i 2), wherein the two-gear reduction box is lifted from the first gear to the second gear, and then is lowered from the second gear to the first gear to form a cycle, and the cycle is performed for C2 times;
c) Integrally circulating the step A) and the step B) for D times;
d) After the circulation is finished, the two-gear reduction gearbox is checked;
the total friction work of the synchronizer of the two-gear reduction box in the test needs to be covered by the total friction work W of the synchronizer of the two-gear reduction box in the specified service life Target Namely:
(2*E1*C1+2*E2*C2)*D≥β*W target
In the formula, beta is a verification coefficient, E1 is single-cycle friction work of upshifting or downshifting under a small rotating speed difference shifting working condition, E2 is single-cycle friction work of upshifting or downshifting under a medium rotating speed difference shifting working condition, E = 0.5J (2 pi Δ N/60) ^2, in the formula, J is the sum of rotating inertia values of a two-gear reduction box and a motor rotating inertia simulation device, and Δ N = N max The obtained value is E1, delta n = alpha Vmax Slipping of the ball * The result is E2 when the value is 1000X 2/d 60/2 pi.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202210853418.1A CN115326381A (en) | 2022-07-08 | 2022-07-08 | Gear shifting endurance test device and test method for two-gear reduction gearbox |
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| CN202210853418.1A CN115326381A (en) | 2022-07-08 | 2022-07-08 | Gear shifting endurance test device and test method for two-gear reduction gearbox |
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| CN115326381A true CN115326381A (en) | 2022-11-11 |
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| CN202210853418.1A Pending CN115326381A (en) | 2022-07-08 | 2022-07-08 | Gear shifting endurance test device and test method for two-gear reduction gearbox |
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