36results about How to "Improve cornering maneuverability" patented technology

The invention discloses a double-motor coupling drive axle with a torque directional distribution function. The double-motor coupling drive axle comprises a main driving mechanism, a bevel gear differential, a TV control driving mechanism, a first single-row planetary gear system, a second single-row planetary gear system, a third single-row planetary gear system, a first clutch, a third clutch, a second clutch and a fourth clutch. A first sun gear of the first single-row planetary gear system is rotatably supported on a first halt shaft, and a first gear ring is connected with the output end of the TV control driving mechanism. A second gear ring of the second single-row planetary gear system is fixed on a drive axle shell body, and a second sun gear is coaxially and fixedly connected with the first sun gear. A third sun gear of the third single-row planetary gear system is fixedly connected with a second planetary frame, and a third gear ring is fixedly connected with a differential shell. The first clutch is used for separating the first half shaft from a first planetary frame or connecting the first half shaft with the first planetary frame. The third clutch is used for separating the first half shaft from a third planetary frame or connecting the first half shaft with the third planetary frame. The second clutch is used for separating the first planetary frame from the drive axle shell body or connecting the first planetary frame with the drive axle shell body. The fourth clutch is used for separating the third planetary frame from the drive axle shell body or connecting the third planetary frame with the drive axle shell body.

The invention belongs to the field of connection systems for every two adjacent carriages of a railway vehicle and relates to a traveling device used between adjacent train bodies of a motor train unit and capable of reducing the floor height. The traveling device is a low-gravity-center compact common bogie of a brand new form. An oil damper of the traveling device is used for restraining relative rolling pendulum vibration between the top of a carriage A and the top of a carriage B. The two ends of a common connecting device are fixed to underframe end beams of the two adjacent carriages respectively. Four air spring installation positions arranged on two sides are uniquely arranged on a common framework so as to contain sleeper beam middle through grooves. Under the condition that the existing fixed distance of each carriage of the motor train unit is kept unchanged, the traveling device can reduce the total number of bogies of the motor train unit and reduce the manufacturing cost of the motor train unit; moreover, while the un-obstruction performance of the interior floor of the motor train unit is improved, the overall gravity center and the floor height of the motor train unit are lowered, and passengers can conveniently get on or off the motor train unit. In addition, the traveling device remarkably improves the bend curve passage capacity and the turning maneuvering performance of the motor train unit.

The invention discloses a duplex planetary gear train torque directional distribution electric drive axle. The drive axle comprises a main drive motor, a TV control drive motor and a duplex planetarygear train, wherein a power output shaft of the main drive motor is connected with a gear ring of a two-stage planet gear planet row differential mechanism; a sun gear of the two-stage planet gear planet row differential mechanism is connected with a first axle shaft, and a planet carrier of the two-stage planet gear planet row differential mechanism is connected with a second axle shaft; the duplex planetary gear train comprises a first sun gear, a second sun gear, a first end planet gear, a second end planet gear and a first planet carrier; the first sun gear is connected with the first axleshaft, and the second sun gear is rotationally supported on the first axle shaft and connected with the planet carrier of the two-stage planet gear planet row differential mechanism; and the first end planet gear and the second end planet gear are coaxially arranged on a planet shaft, and the planet shaft is connected with a power output shaft of the TV control drive motor through the first planet carrier. Torque directional distribution of wheels on the two sides can be achieved without a clutch, and the structure is simple.

The invention discloses a double-motor coupling driving bridge with a torque directional distribution function. The double-motor coupling driving bridge with the torque directional distribution function comprises a master driving mechanism, a spur gear differential, a TV control driving mechanism, a first single row planetary gear system, a second single row planetary gear system, a third single row planetary gear system, a first clutch, a second clutch, a third clutch and a fourth clutch, wherein a first sun gear of the first single row planetary gear system can be rotatably supported on a first half shaft, and a first gear ring is connected with the output end of the TV control driving mechanism; a second gear ring of the second single row planetary gear system is fixed to a driving bridge shell, and a second sun gear is coaxially and fixedly connected with the first sun gear; a third sun gear of the third single row planetary gear system is fixedly connected with a differential shell, and a third gear ring is fixedly connected with a second planetary frame; the first clutch is used for isolating or combining the first half shaft and a first planetary frame; the second clutch is used for isolating or combining the first planetary frame and the driving bridge shell; the third clutch is used for isolating or combining the first half shaft and a third planetary frame; and the fourth clutch is used for isolating or combining the third planetary frame and the driving bridge shell.

The invention provides a self-adaptive vehicle curve auxiliary control method and device, computer equipment and a storage medium. The method comprises the steps that S10, the type of a current curveis recognized according to signals of a sensor of a vehicle, and the lateral impact degree of the current vehicle is obtained according to the lateral acceleration corresponding to the type of the curve; S11, calculation is performed according to the lateral impact degree to obtain an expected longitudinal acceleration; S12, according to the expected longitudinal acceleration and the current actual longitudinal acceleration, an activation type of current curve auxiliary control is determined; and S13, according to the activation type, the engine torque or / and the ESC braking strength is / are cooperatively controlled, and expected longitudinal control over the curve of the vehicle is achieved. Certain vehicle longitudinal auxiliary control can be carried out on the premise that a driver doesnot perceive, so that the dynamic performance of the vehicle during turning is improved.

The invention discloses an electric differential mechanism with a directed torque distribution function. The electric differential mechanism with the directed torque distribution function comprises a main drive mechanism, a bevel gear differential mechanism body, a TV control drive mechanism used for outputting control power, a first single-row planetary gear system, a second single-row planetary gear system and a third single-row planetary gear system, wherein a first sun gear is supported on a first half axle through a bearing, a first gear ring is coaxially and fixedly connected with the first half axle, and a first planetary carrier is connected with the control output end; a second planetary carrier is fixed to a drive axle housing, and a second sun gear is fixedly connected with the first sun gear; the second sun gear is supported on the first half axle through a bearing; a third sun gear is fixedly connected with a differential mechanism shell, a third planetary carrier is fixedly connected with a second inner gear ring, and a third gear ring is fixedly connected with the first half axle; and the second single-row planetary gear system and the first single-row planetary gear system have the same characteristic parameters. By means of the electric differential mechanism with the directed torque distribution function, drive torque of an automobile can be distributed to wheels on the left side and the right side in a directed mode according to control demands of control logic.

The invention provides a torque directional distribution electric drive axle design method. The method includes the following steps that parameter matching calculation of a main drive motor of a torque directional allocation electric drive axle is completed according to vehicle dynamic indexes, the speed ratio of a cylindrical gear main speed reducer of the torque directional allocation electric drive axle is calculated according to the speed of a cruiser, and the number of stages of the main speed reducer is determined; the feature parameters k1 and k2 of a two-row planetary gear TV mechanism and the feature parameter k0 of a single-row two-line planetary gear coupling mechanism are calculated; the maximum differential torque deltaTmax of a torque directional distributor is calculated; the range of the peak torque T1038max of a TV control motor is determined, the range of the peak rotation speed n1038max of the TV control motor is determined, and a TV control motor is selected according to the ranges; the transmission ratio C of planetary gear speed reduction mechanisms is calculated according to deltaTmax and T1038max, the number of rows of the planetary gear speed reduction mechanisms of the torque directional distribution electric drive axle is determined, and feature parameters k3, (k4) and (k5) of each row are determined according to optimization targets, with the minimum feature parameter difference, of the planetary gear speed reduction mechanisms.

The invention discloses an electric differential mechanism with a torque oriented distribution function. The electric differential mechanism comprises a main drive mechanism, a bevel gear differential mechanism, a TV control drive mechanism, a first single-row planetary gear train, a second single-row planetary gear train and a third single-row planetary gear train. The TV control drive mechanism is used for outputting control power. A first sun gear is coaxially and fixedly connected with a first half shaft. A first gear ring is connected with a control output end. A second gear ring is fixed to a drive axle housing. A second planet carrier is fixedly connected with a first planet carrier. A second sun gear is supported on the first half shaft through a bearing. A third sun gear is fixedly connected with a differential mechanism shell. A third planet carrier is connected with the first half shaft through a spline. A third gear ring is fixedly connected with the second sun gear. The second single-row planetary gear train and the first single-row planetary gear train have the same characteristic parameters. By means of the electric differential mechanism, the drive torque of automobiles can be distributed to wheels on the left side and the right side in an oriented manner according to control requirements of control logic.

The invention discloses a torque directional distribution electric drive axle based on a double-rotor motor. The drive axle comprises a main drive motor and the relatively-rotating type double-rotor motor, wherein the output end of the main drive motor is connected with a shell of a bevel gear differential mechanism through a speed reduction mechanism; the relatively-rotating type double-rotor motor comprises an outer rotor and an inner rotor which are coaxially arranged and rotate relatively; a first output end drive gear of a first output end gear transmission mechanism is fixedly connectedwith the output end of the outer rotor of the double-rotor motor, and a first output end driven gear is connected with a first axle shaft; a second output end drive gear of a second output end gear transmission mechanism is fixedly connected with the output end of the inner rotor of the double-rotor motor, and a second output end driven gear is fixedly connected with the shell of the bevel gear differential mechanism; and the first output end gear transmission mechanism and the second output end gear transmission mechanism have the same transmission ratio. By the adoption of the provided torque directional distribution electric drive axle based on the double-rotor motor, torque directional distribution of wheels on the two sides can be achieved without a clutch, the action response is madequickly, and the integration degree is high.

The invention discloses an electric differential mechanism with a torque directional allocation function. The electric differential mechanism comprises a main driving mechanism, a bevel gear differential mechanism body, a TV control driving mechanism, a first single-row planetary gear train, a second single-row planetary gear train and a third single-row planetary gear train, wherein the TV control driving mechanism is used for outputting control power; a first sun gear is supported on a first half shaft through a bearing, a first gear ring is coaxially and fixedly connected with the first half shaft, and a first planet carrier is connected with a control output end; a second planet carrier is fixed to a driving axle housing, and a second sun gear is fixedly connected with the first sun gear and supported on the first half shaft through a bearing; a third sun gear is fixedly connected with a differential mechanism shell, a third planet carrier is in spline connection with the first half shaft, and a third gear ring is fixedly connected with a second inner gear ring; and the second single-row planetary gear train and the first single-row planetary gear train have the same characteristic parameters. By adoption of the electric differential mechanism, the driving torque of an automobile can be allocated directionally to left side wheels and right side wheels according to control requirements of control logic.

The invention discloses an electric differential mechanism with a directed torque distribution function. The electric differential mechanism with the directed torque distribution function comprises a main drive mechanism, a bevel gear differential mechanism body, a TV control drive mechanism used for outputting control power, a first single-row planetary gear system, a second single-row planetary gear system and a third single-row planetary gear system, wherein a first sun gear is coaxially and fixedly connected with a first half axle, and a first planetary carrier is connected with the control output end; a second planetary carrier is fixed to a drive axle housing, and a second gear ring is fixedly connected with a first gear ring; a second sun gear is supported on the first half axle through a bearing; a third sun gear is fixedly connected with the second sun gear, a third planetary carrier is fixedly connected with a differential mechanism shell, and a third gear ring is fixedly connected with the first half axle; and the second single-row planetary gear system and the first single-row planetary gear system have the same characteristic parameters. By means of the electric differential mechanism with the directed torque distribution function, drive torque of an automobile can be distributed to wheels on the left side and the right side in a directed mode according to control demands of control logic.

The invention provides a method and a structure for adjusting the vertical rigidity of a primary suspension device. The primary suspension device comprises a base, conical springs and limiting stoppers, each conical spring comprises a rubber body and a mandrel, a stopping hole is formed in the lower end of a bogie, the upper end of the mandrel is installed in the stopping hole of the bogie, and cavities are formed in the rubber body and the mandrel; the two conical springs are arranged in the base side by side in the longitudinal direction, the limiting stoppers are arranged in the cavities ofthe conical springs, each limiting stopper comprises a stop base and a stop rod, and the stop rod is integrally formed above the stop base; and an axle box is provided with an axle box seat, the baseis installed in the axle box seat, and when the bogie moves relative to the axle box in the vertical direction and the lower end of the mandrel abuts against the stop seats in the vertical direction,the primary suspension device can generate variable rigidity in the vertical direction. The capacity of a vehicle for passing through a small-curvature-radius curve can be remarkably improved, the primary suspension space is greatly saved, and the weight of the bogie is reduced.

The invention discloses an electric differential mechanism with a directed torque distribution function. The electric differential mechanism with the directed torque distribution function comprises a main drive mechanism, a bevel gear differential mechanism body, a TV control drive mechanism used for outputting control power, a first single-row planetary gear system, a second single-row planetary gear system and a third single-row planetary gear system, wherein a first planetary carrier is coaxially and fixedly connected with a first half axle, a first gear ring is connected with the control output end, and a first sun gear is supported on the first half axle through a bearing; a second gear ring is fixed to a drive axle housing, and a second sun gear is fixedly connected with the first sun gear and supported on the first half axle through a bearing; a third sun gear is fixedly connected with a differential mechanism shell, a third planetary carrier is fixedly connected with a second planetary carrier, and a third gear ring is fixedly connected with the first half axle; and the second single-row planetary gear system and the first single-row planetary gear system have the same characteristic parameters. By means of the electric differential mechanism with the directed torque distribution function, drive torque of an automobile can be distributed to wheels on the left side and the right side in a directed mode according to control demands of control logic.

The invention discloses an electric differential mechanism with a torque fixed direction allocation function. The electric differential mechanism comprises a main driving mechanism, a bevel gear main differential mechanism, a TV control driving mechanism, a first single row planetary gear system, a second single row planetary gear system and a third single row planetary gear system. The TV control driving mechanism is used for outputting control power; a first sun gear is fixedly coaxially connected to a first axle shaft, and a first gear ring is connected to a control output end; a second gear ring is fixed on a driving axle housing, and a second planetary frame is fixedly connected to the first planetary frame; a second sun gear is rotatably supported on the first axle shaft; a third sun gear is fixedly connected to the second sun gear, a third planetary frame is fixedly connected to a differential housing, and a third gear ring is fixedly connected to the first axle shaft, wherein the second single row planetary gear system has the same characteristic parameter as the first single row planetary gear system. The electric differential mechanism with the torque fixed direction allocation function enables driving torque of a vehicle to be directionally distributed to wheels at the left and right sides according to a control requirement of control logic.

The invention discloses an electric differential with a torque oriented distribution function. The electric differential comprises a main driving mechanism, a bevel gear differential, a TV control driving mechanism, a first single rod planetary gear train, a second single rod planetary gear train and a third single rod planetary gear train, wherein the TV control driving mechanism is used for outputting control power; a first planet carrier and a first half shaft are coaxially and fixedly connected; a first gear ring is connected with a control output end; a first sun gear is supported on the first half shaft through a bearing; a second gear ring is fixed to a drive axle housing; a second sun gear is fixedly connected with the first sun gear; the second sun gear is supported on the first half shaft through a bearing; a third sun gear is fixedly connected with the first half shaft; a third gear ring is fixedly connected with a second planet carrier; a third planet carrier is fixedly connected with a differential case; and the second single rod planetary gear train and the first single rod planetary gear train have the same characteristic parameters. According to the electric differential, driving torque of an automobile can be distributed to wheels on the left and right sides in an oriented manner according to the control requirement of control logic.

The invention discloses an electric differential device with a torque fixed-direction distribution function. The electric differential device comprises a main drive mechanism, a bevel gear differential device body, a TV control drive mechanism for outputting control power, a first single-row planetary gear system, a second single-row planetary gear system and a third single-row planetary gear system; a first sun gear is coaxially and fixedly connected with a first half shaft, and a first planet carrier is connected with the control output end; a second planet carrier is fixed to a drive bridge shell, and a second gear ring is fixedly connected with a first gear ring; a second sun gear is arranged on the first half shaft through a bearing in a supported manner; a third sun gear is fixedly connected with a differential device shell, a third planet carrier is connected with the first half shaft through a spline, and a third gear ring is fixedly connected with the second sun gear; and the second single-row planetary gear system and the first single-row planetary gear system have the same characteristic parameters. By means of the electric differential device, the drive torque of an automobile can be distributed to wheels on the left side and the right side in a fixed-direction manner according to the control requirement of control logic.

The invention discloses an electric differential device with a torque fixed-direction distribution function. The electric differential device comprises a main drive mechanism, a bevel gear differential device body, a TV control drive mechanism for outputting control power, a first single-row planetary gear system, a second single-row planetary gear system and a third single-row planetary gear system; a first planet carrier is coaxially and fixedly connected with a first half shaft, a first gear ring is connected with the control output end, and a first sun gear is arranged on the first half shaft through a bearing in a supported manner; a second gear ring is fixed to a drive bridge shell, and a second sun gear is fixedly connected with the first sun gear; the second sun gear is arranged on the first half shaft through a bearing in a supported manner; a third sun gear is fixedly connected with the first half shaft, a third planet carrier is fixedly connected with a second planet carrier, and a third gear ring is fixedly connected with a differential device shell; and the second single-row planetary gear system and the first single-row planetary gear system have the same characteristic parameters. By means of the electric differential device, the drive torque of an automobile can be distributed to wheels on the left side and the right side in a fixed-direction manner according to the control requirement of control logic.

The invention discloses a duplex planetary gear train torque directional distribution electric drive axle. The drive axle comprises a main drive motor, a TV control drive motor and a duplex planetarygear train, wherein a power output shaft of the main drive motor is connected with a shell of a bevel gear differential mechanism through a speed reduction mechanism; a first axle shaft is rotationally supported on the shell, penetrates through the shell and is connected with a first axle shaft gear of the bevel gear differential mechanism, and a second axle shaft is rotationally supported on theshell, penetrates through the shell and is connected with a second axle shaft of the bevel gear differential mechanism; and the duplex planetary gear train comprises a first sun gear, a second sun gear, a first end planet gear, a second end planet gear and a first planet carrier. The torque of wheels on the left side and the right side is distributed at will.

The invention belongs to the field of connection systems for every two adjacent carriages of a railway vehicle and relates to a traveling device used between adjacent train bodies of a motor train unit and capable of reducing the floor height. The traveling device is a low-gravity-center compact common bogie of a brand new form. An oil damper of the traveling device is used for restraining relative rolling pendulum vibration between the top of a carriage A and the top of a carriage B. The two ends of a common connecting device are fixed to underframe end beams of the two adjacent carriages respectively. Four air spring installation positions arranged on two sides are uniquely arranged on a common framework so as to contain sleeper beam middle through grooves. Under the condition that the existing fixed distance of each carriage of the motor train unit is kept unchanged, the traveling device can reduce the total number of bogies of the motor train unit and reduce the manufacturing cost of the motor train unit; moreover, while the un-obstruction performance of the interior floor of the motor train unit is improved, the overall gravity center and the floor height of the motor train unit are lowered, and passengers can conveniently get on or off the motor train unit. In addition, the traveling device remarkably improves the bend curve passage capacity and the turning maneuvering performance of the motor train unit.

The invention discloses an electric differential mechanism with a torque directional distributing function. The electric differential mechanism comprises a main drive mechanism, a bevel gear differential mechanism, a TV control drive mechanism used for outputting control power, a first single-row planet gear train, a second single-row planet gear train and a third single-row planet gear train. A first sun gear is supported on a first half shaft through a bearing, a first gear ring is coaxially and fixedly connected with the first half shaft, and a first planet carrier is connected with the control output end. A second planet carrier is fixed to a drive axle housing, and a second sun gear is fixedly connected with the first sun gear. A second sun gear is supported on the first half shaft through a bearing. A third sun gear is fixedly connected with a second inner gear ring, a third planet carrier is fixedly connected with a differential mechanism shell, and a third gear ring is fixedly connected with the first half shaft. The second single-row planet gear train and the first single-row planet gear train are the same in characteristic parameter. According to the electric differential mechanism, the drive torque of an automobile can be directionally distributed to wheels on the left side and the right side according to the control requirement of the control logic.

The invention discloses a lightweight axle box built-in primary suspension device and a lightweight design method. An axle box seat is arranged on an axle box of a vehicle, a stop hole is formed in the lower end of a bogie, the lower end of the primary suspension device is installed in the axle box seat, and the upper end of the primary suspension device is installed in a stop hole of the bogie. According to the invention, the capacity of a vehicle for passing through a small-curvature-radius curve can be remarkably improved, the primary suspension space is greatly saved, and the weight of thebogie is reduced. The minimum curve passing radius of the bogie of the vehicle is remarkably reduced compared with that of a common bogie, so that the turning maneuverability and flexibility of the bogie are greatly improved, and the loading capacity, the dynamic performance and the critical speed of the whole vehicle are improved.

The invention discloses an electric differential mechanism with a torque directional distribution function. The electric differential mechanism comprises a main driving mechanism, a cone gear differential mechanism, a TV control driving mechanism; a first signal row of planetary gear system, a second signal row of planetary gear system, and a third row of planetary gear system, wherein the TV control driving mechanism is used for outputting control power; a first sun wheel is coaxially and fixedly connected with a first half axle, and a first gear ring is connected with a control output end; a second gear ring is fixed on a driving axle shell, and a second planetary rack is fixedly connected with a first planetary rack; a second sun wheel is supported on the first half axle by a bearing; a third sun wheel is fixedly connected with the second sun wheel, a third planetary rack is fixedly connected with the first half axle, and the third gear ring is fixedly connected with a differential mechanism shell; the second signal row of planetary gear system, and the first single row of planetary gear system have same characteristic parameters. According to the electric differential mechanism disclosed by the invention, driving torque of an automobile can be directionally distributed to a left-sided wheel and a right-sided wheel according to a control requirement of control logic.

The invention discloses an electric differential with a directional torque distribution function. The electric differential comprises a main driving mechanism, a bevel gear differential, a TV control driving mechanism, a first single-row planetary gear train, a second single-row planetary gear train and a third single-row planetary gear train, wherein the TV control driving mechanism is used for outputting control power; a first sun wheel and a first half shaft are coaxially and fixedly connected, and a first planetary carrier is connected with the control output end; a second planetary carrier is fixed to a driving axle shell, and a second gear ring is fixedly connected with a first gear ring; a second sun wheel is supported on the first half shaft through a bearing; a third sun wheel is fixedly connected with the second sun wheel, a third planetary carrier is fixedly connected with the first half shaft, and a third gear ring is fixedly connected with a differential shell; and the second single-row planetary gear train and the first single-row planetary gear train have the same characteristic parameters. According to the electric differential, the driving torque of an automobile can be distributed to wheels on the left side and the right side in a directional mode according to control requirements of the control logic.

The invention provides an adaptive vehicle curve assist control method, device, computer equipment and storage medium. The method includes: step S10, identifying the type of the current curve according to the signal of the sensor of the vehicle, corresponding to the type of the curve, obtaining the lateral impact of the current vehicle according to the lateral acceleration; step S11, according to The lateral impact is calculated to obtain the expected longitudinal acceleration; step S12, according to the expected longitudinal acceleration and the current actual longitudinal acceleration, determine the current activation type of the curve assist control; step S13, according to the activation Type, cooperatively control the engine torque or / and ESC braking strength to achieve the desired longitudinal control of the vehicle in curves. The present invention can carry out certain vehicle longitudinal auxiliary control on the premise that the driver does not notice, so as to improve the dynamic performance of the vehicle when turning.

Provided are a rigidity adjusting method and structure for conical springs of a primary suspension device. The primary suspension device comprises a base, conical springs and limiting stoppers. Each conical spring comprises a rubber body and a mandrel. Stopping holes are formed in the lower end of a bogie, and the upper ends of the mandrels are installed in the stopping holes of the bogie. Cavities are formed in the rubber bodies and the mandrels. The two conical springs are arranged in the base side by side in the longitudinal direction, one limiting stopper is arranged in a cavity of each conical spring, and the lower end of each limiting stopper is connected with the base. An axle box is provided with an axle box seat, and the base is installed in the axle box seat. When the bogie movesrelative to the axle box in the vertical direction and the lower ends of the mandrels abut against the limiting stoppers, the primary suspension device can generate variable rigidity in the verticaldirection. According to the invention, the capacity of a vehicle for passing through a small-curvature-radius curve can be remarkably improved, the primary suspension space is greatly saved, and the weight of the bogie is reduced.

The invention discloses a transverse and longitudinal rigidity adjusting method and structure of a primary suspension device. The primary suspension device comprises a base, a top plate, conical springs and a limiting stopper; cavities are formed in the conical springs; and the two conical springs are arranged between the base and the top plate side by side in the longitudinal direction. A limiting stopper is arranged in the cavity of each conical spring; the lower end of the limiting stopper is connected with the base; an axle box seat is arranged on an axle box, the base is installed in theaxle box seat, a stop hole is formed in the lower end of a bogie, the upper end of each conical spring further penetrates through the top plate to extend into the stop hole of the bogie, and when thebogie moves relative to the axle box in the transverse direction or the longitudinal direction and the limiting stop abuts against the inner sides of the conical springs, the primary suspension devicecan generate variable rigidity. According to the invention, the capacity of a vehicle for passing through a small-curvature-radius curve can be remarkably improved, the primary suspension space is greatly saved, and the weight of the bogie is reduced.