A kind of circulating ball type electric power steering gear

Abstract

This invention relates to the field of frame equipment technology, and in particular to a recirculating ball type electric power steering system, comprising a steering power shaft; a steering assembly, mounted on the output end of the steering power shaft, which transmits signals through a Hella sensor after the steering power shaft rotates; a transmission mechanism, mounted on one end of the steering assembly, which provides power to the worm gear after receiving the transmitted signal; and a lubrication mechanism, mounted on one end of the transmission mechanism, which lubricates the threaded rod of the recirculating ball type mechanical steering system and simultaneously limits the movement of the threaded rod. It features light and flexible steering, active self-centering, autonomous driving, and assisted driving. Employing a Hella torque sensor capable of simultaneously outputting torque and angle signals, it offers more sensitive sensing, enabling not only active self-centering, autonomous driving, and assisted driving while ensuring power assist, but also light and flexible steering with a smooth and continuous feel.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vehicle steering devices, in particular to a circulating ball type electric power steering gear. BACKGROUND

[0002] At present, the vehicle steering gear mainly adopts electric power assistance type, which is divided into three types of column type, rack and pinion type and circulating ball type. The electric power steering gear directly provides assistance by electric motor. The electric power steering system mainly includes steering wheel torque sensor, vehicle speed sensor, controller, power motor and speed reducer mechanism, etc. The basic principle is that the controller receives the steering wheel torque signal, vehicle speed signal and engine signal, and outputs the control signal to control the power motor to output the assistance torque according to the predetermined assistance characteristic. The electric power steering system has many advantages such as energy saving, high safety performance, being conducive to environmental protection, etc., and is one of the development directions of future power steering technology. However, there are still many problems in the current electric power steering system: first, most of them are only applied to cars, and all are column type or rack and pinion type steering gears, with narrow application range. At present, special vehicles with front axle above 1.5t still use hydraulic power steering, which is complex to install, has large energy loss, and the wear between the gear and the rack is more serious after long time use; second, the existing electric power steering gear adopts torque sensor which can only output torque signal, and the system steering is not light and flexible enough to realize unmanned driving and auxiliary driving; third, the speed reducer part and the mechanical circulating ball structure connecting mechanism are not reasonably arranged, which causes inconvenient assembly and low product assembly qualification.

[0003] And the rocker arm shaft power type circulating ball electric power steering gear provided by CN112829825A is complex to install and has large energy loss in use. The adopted sensor is torque sensor which can only output torque signal, and the system steering is not light and flexible enough to realize unmanned driving and auxiliary driving. Meanwhile, the speed reducer part and the mechanical circulating ball structure connecting mechanism are not reasonably arranged. SUMMARY

[0004] In view of the above problems existing in the prior art, a circulating ball type electric power steering gear is provided.

[0005] The specific technical scheme is as follows: the steering is flexible and can assist driving, the wear between the gear and the rack is reduced, the application range is wide, and the assembly is convenient.

[0006] A circulating ball type electric power steering gear is designed, which includes a steering power shaft;

[0007] A steering assembly is assembled on the output end of the steering power shaft, so that the steering power shaft rotates and transmits the signal to the outside through the hall sensor;

[0008] A transmission mechanism is assembled at one end of the steering assembly, and the transmission mechanism provides power to the worm after receiving the transmission signal;

[0009] A lubricating mechanism is assembled at one end of the transmission mechanism, lubricates the threaded rod, and limits the threaded rod. The steering power shaft and the threaded rod of the recirculating ball mechanical steering gear are connected through a helical spline structure.

[0010] Preferably, the steering assembly includes a cover plate, a reducer housing, and a steering gear housing. The inner surface of the hall sensor is rotatably connected to the outer surface of the steering power shaft, and the bottom of the hall sensor is connected to a sensor bearing sleeve.

[0011] Preferably, the inner cavity of the reducer housing is provided with a worm, and the bottom end of the steering power shaft is provided with a worm shaft. The outer surface of the worm shaft is provided with a worm gear.

[0012] Preferably, the inner cavity of the steering gear housing is provided with a limiting nut, and the middle part of the inner cavity of the steering gear housing is provided with a steering rack. The inner surface of the steering rack is provided with a rotatable threaded rod, the outer surface of the threaded rod is slidably provided with a steel ball, the bottom of the limiting nut is provided with a first thrust ball bearing, and the bottom of the inner cavity of the steering gear housing is provided with a second thrust ball bearing.

[0013] Preferably, one end of the steering gear housing is provided with an oil seal, the bottom of the oil seal is connected to a needle bearing, and one end of the threaded rod is connected to a steering rocker shaft.

[0014] Preferably, the transmission mechanism includes an integrated motor controller, the output end of the integrated motor controller is connected to a worm, the outer surface of the worm is provided with a connecting sleeve, the inner cavity of the steering gear housing is provided with a locking nut, and one end of the locking nut is connected to a pressing nut.

[0015] Preferably, one end of the pressing nut is connected to a check ring, the inner cavity of the check ring is provided with a first ball bearing, and both sides of the top end of the worm are provided with a second ball bearing.

[0016] Preferably, the lubricating mechanism includes a disc, one end of the disc is connected to a pressing block, and the inner cavity of the pressing block is provided with a pressing rod.

[0017] Preferably, one end of the pressing rod penetrates the disc and extends to the inside of the disc, the bottom of the inner cavity of the disc is slidably provided with a lubricating brush, and the top of the lubricating brush is slidably connected to the bottom of the pressing rod.

[0018] Preferably, one end of the pressing rod is connected to an elastic mechanism, and the bottom of the lubricating brush penetrates the disc and extends to the outside of the disc.

[0019] The above technical scheme has the following advantages or beneficial effects:

[0020] 1、The present application has the advantages of light and flexible steering, active return, unmanned driving, and auxiliary driving. The Haila torque sensor can output torque signals and angle signals simultaneously, and is more sensitive. It can not only realize active return, unmanned driving, and auxiliary driving, but also ensure the assistance effect, and the steering is light and flexible, and the hand feeling is continuous and smooth.

[0021] 2、The present application has the advantages of simple mechanism and convenient assembly. The screw rod of the steering power shaft and the circulating ball type mechanical steering gear is connected through a helical spline structure, the worm gear is supported by ball bearings in front and back, the sensor is through the main transmission shaft, and the steering screw rod is supported by thrust ball bearings in front and back. The mechanism is stable and reliable, and the assembly method is simple. Four-φ15 mounting holes are arranged on the right end face of the steering gear housing. The installation on the frame is very convenient, and the connection size can be interchanged with the mechanical steering of the vehicle.

[0022] 3、The present application has the advantages of reducing energy consumption and pollution. The motor used is a direct-current brushless motor, the output power is 850W, the output torque is 8N.m, and the rated voltage is 24V. The power loss of the engine is reduced, the oil is saved, the pollution is reduced, and the low-temperature working performance of the steering system is improved.

[0023] 4、The present application has the advantages of reducing the wear between the steering rack and the threaded rod, limiting the threaded rod, preventing the threaded rod from being dislocated, and lubricating the threaded rod through a lubricating brush, effectively prolonging the service life of the threaded rod and the steering rack. BRIEF DESCRIPTION OF DRAWINGS

[0024] Reference will now be made to the accompanying drawings, which illustrate the embodiments of the application more fully. However, the accompanying drawings are only used for illustration and explanation, and do not constitute a limitation on the scope of the application.

[0025] Figure 1 It is an internal front view of the structure of the embodiment of the present application.

[0026] Figure 2 It is an internal side view of the structure of the embodiment of the present application.

[0027] Figure 3 It is an internal top view of the structure of the embodiment of the present application.

[0028] Figure 4 It is a lubricating mechanism structure of the embodiment of the present application.

[0029] Figure 5 It is a lubricating mechanism internal structure of the embodiment of the present application.

[0030] Figure 6Fig. 1 is a schematic diagram of the internal structure of a disc according to an embodiment of the present application;

[0031] Figure 7 Fig. 2 is a perspective view of the disc structure according to an embodiment of the present application;

[0032] Figure 8 Fig. 3 is a front view of the disc structure according to an embodiment of the present application.

[0033] The above reference signs represent:

[0034] 1, steering power shaft; 2, steering assembly; 3, transmission mechanism; 4, lubricating mechanism; 21, Hall sensor; 22, cover plate; 23, reducer housing; 24, steering gear housing; 25, sensor bearing sleeve; 26, worm; 27, worm shaft; 28, worm gear; 241, limiting nut; 242, steering rack; 243, threaded rod; 244, steel ball; 245, first thrust ball bearing; 246, second thrust ball bearing; 247, oil seal; 248, needle bearing; 249, steering rocker shaft; 31, worm; 32, integrated motor controller; 33, connecting sleeve; 34, locking nut; 35, pressing nut; 36, retaining ring; 37, first ball bearing; 38, second ball bearing; 41, disc; 42, pressing block; 43, pressing rod; 44, lubricating brush; 45, elastic mechanism. DETAILED DESCRIPTION

[0035] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of protection of the present application.

[0036] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application; the terms "first", "second", "third" are only for the purpose of description, and cannot be understood as indicating or implying relative importance, in addition, unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting" should be understood in a broad sense, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0037] Referring to Figures 1-8 , a circulating ball type electric power steering gear, comprising a steering power shaft 1;

[0038] A steering assembly 2 is assembled to the output end of the steering power shaft 1, so that the steering power shaft 1 rotates and transmits signals to the outside through the hall sensor 21;

[0039] A transmission mechanism 3 is assembled to one end of the steering assembly 2, and after receiving the transmission signal, the transmission mechanism 3 provides power to the worm 26;

[0040] A lubricating mechanism 4 is assembled to one end of the transmission mechanism 3, which lubricates the threaded rod 243 and limits the threaded rod 243 at the same time, and the threaded rod 243 of the circulating ball type mechanical steering gear is connected through the helical spline structure.

[0041] The threaded rod 243 is horizontally installed inside the steering gear housing 24 through the second thrust ball bearing 246 and the first thrust ball bearing 245 at both ends respectively; the threaded rod 243 is sleeved with a steering rack 242; the inner thread raceway of the steering rack 242 and the outer thread raceway of the threaded rod 243 are connected by steel balls 244 and steel ball guide pipes to form a steel ball circulating raceway, and a plurality of steel balls 244 are arranged in the steel ball circulating raceway; the rack on the outer side of the steering rack 242 is engaged with the sector gear of the steering rocker shaft 249 below it

[0042] As Figure 1 shown, on the basis of the above technical solution, further, the steering assembly 2 is described, the steering assembly 2 comprises a cover plate 22, a reducer housing 23 and a steering gear housing 24, the inner surface of the hall sensor 21 is rotatably connected with the outer surface of the steering power shaft 1, and the bottom of the hall sensor 21 is connected with a sensor bearing sleeve 25.

[0043] The inner cavity of the speed reducer shell 23 is mounted with a worm 26, the bottom end of the steering power shaft 1 is mounted with a worm shaft 27, and the outer surface of the worm shaft 27 is fitted with a worm wheel 28.

[0044] As shown in Figure 1 , on the basis of the above technical scheme, further, the steering gear housing 24 is described, the inner cavity of the steering gear housing 24 is fitted with a limiting nut 241, the middle part of the inner cavity of the steering gear housing 24 is mounted with a steering rack 242, the inner surface of the steering rack 242 is mounted with a rotatable threaded rod 243, the outer surface of the threaded rod 243 is slidingly mounted with a steel ball 244, the bottom of the limiting nut 241 is fitted with a first thrust ball bearing 245, and the bottom of the inner cavity of the steering gear housing 24 is fitted with a second thrust ball bearing 246.

[0045] As shown in Figure 2 , on the basis of the above technical scheme, further, the steering gear housing 24 is described, one end of the steering gear housing 24 is fitted with an oil seal 247, the bottom of the oil seal 247 is connected with a needle bearing 248, one end of the threaded rod 243 is connected with a steering rocker shaft 249.

[0046] As shown in Figure 3 , on the basis of the above technical scheme, further, the transmission mechanism 3 is described, the transmission mechanism 3 comprises an integrated motor controller 32, the output end of the integrated motor controller 32 is connected with a worm 31, the outer surface of the worm 31 is mounted with a connecting sleeve 33, the inner cavity of the steering gear housing 24 is mounted with a locking nut 34, one end of the locking nut 34 is connected with a compression nut 35.

[0047] One end of the compression nut 35 is connected with a check ring 36, the inner cavity of the check ring 36 is fitted with a first ball bearing 37, and both sides of the top end of the worm 31 are fitted with a second ball bearing 38.

[0048] As shown in Figure 5 , on the basis of the above technical scheme, further, the lubricating mechanism 4 is described, the lubricating mechanism 4 comprises a disc 41, one end of the disc 41 is connected with a pressing block 42, and the inner cavity of the pressing block 42 is fitted with a pressing rod 43.

[0049] One end of the pressing rod 43 penetrates through the disc 41 and extends to the inside of the disc 41, the bottom of the inner cavity of the disc 41 is slidingly mounted with a lubricating brush 44, and the top of the lubricating brush 44 is slidingly connected with the bottom of the pressing rod 43.

[0050] One end of the pressing rod 43 is connected with an elastic mechanism 45, and the bottom of the lubricating brush 44 penetrates through the disc 41 and extends to the outside of the disc 41.

[0051] Embodiment

[0052] The module of the rack outside the steering nut rack 13 and the sector gear of the steering rocker shaft 19 is 5.5-9, and the module of the rack outside the steering nut rack 13 and the sector gear of the steering rocker shaft 19 is 7.5. The diameter of the steel ball 10 is 7.5-8.5 mm, the reduction gear worm gear transmission ratio is 18-23, and the reduction gear worm gear transmission ratio is 20.5. Four-φ15 mounting holes are arranged on the right end face of the steering gear housing 12, four-φ15 mounting holes are arranged on the right end face of the steering gear housing, the installation on the frame is very convenient, and the connection size can be interchanged with the mechanical steering of the vehicle. The module of the worm 7 and the worm gear is 1.75-3.25, the number of heads of the worm 7 is 2, and the number of teeth of the worm gear is 41. The motor of the integrated motor controller is a direct-current brushless motor, the output power is 850w, the output torque is 8N·m, the rated voltage is 24V, the power-assisted effect and the maximum output torque of the steering gear are ensured, and the installation position of the motor can be arbitrarily changed according to the actual needs of the user. The rotation angle of the steering rocker is ±45°, the transmission ratio is 20.31, the total number of turns of the input end is 5.08 turns, and the maximum output torque is 1600N·m.

[0053] The above only describes the preferred embodiments of the present application, and does not limit the implementation and protection scope of the present application. Those skilled in the art should realize that any equivalent replacement and obvious change made according to the content of the present application should be included in the protection scope of the present application.

Claims

1. A recirculating ball electric power steering gear, The utility model relates to a kind of steering mechanism, which is characterized by comprising: A steering power shaft; A steering assembly is assembled to the output end of the steering power shaft, so that the steering power shaft rotates and sends signals out through a hall sensor; A transmission mechanism is assembled to one end of the steering assembly, and the transmission mechanism provides power to a worm after receiving the transmitted signals; The steering assembly includes a cover plate, a reducer housing and a steering housing, the inner surface of the hall sensor is rotationally connected to the outer surface of the steering power shaft, and the bottom of the hall sensor is connected with a sensor bearing sleeve; The worm is installed in the inner cavity of the reducer housing, the bottom end of the steering power shaft is installed with a worm shaft, and the outer surface of the worm shaft is assembled with a worm gear; The inner cavity of the steering housing is assembled with a limiting nut, the middle part of the inner cavity of the steering housing is installed with a steering rack, the inner surface of the steering rack is installed with a rotatable threaded rod of a circulating ball mechanical steering device, the outer surface of the threaded rod is slidingly installed with a steel ball, the bottom of the limiting nut is assembled with a first thrust ball bearing, and the bottom of the inner cavity of the steering housing is assembled with a second thrust ball bearing; One end of the steering housing is assembled with an oil seal, the bottom of the oil seal is connected with a needle bearing, and one end of the threaded rod is connected with a steering rocker shaft; A lubricating mechanism is assembled to one end of the transmission mechanism to lubricate the threaded rod and limit the threaded rod, and the steering power shaft and the threaded rod are connected through a helical spline structure; The transmission mechanism includes an integrated motor controller, the output end of the integrated motor controller is connected with a worm, the outer surface of the worm is installed with a connecting sleeve, the inner cavity of the steering housing is installed with a locking nut, and one end of the locking nut is connected with a pressing nut; One end of the pressing nut is connected with a retainer, the inner cavity of the retainer is assembled with a first ball bearing, and both sides of the top end of the worm are assembled with a second ball bearing; The lubricating mechanism includes a disc, one end of the disc is connected with a pressing block, and the inner cavity of the pressing block is assembled with a pressing rod; One end of the pressing rod penetrates through the disc and extends to the inside of the disc, the bottom of the inner cavity of the disc is slidingly installed with a lubricating brush, and the top of the lubricating brush is slidingly connected with the bottom of the pressing rod; One end of the pressing rod is connected with an elastic mechanism, and the bottom of the lubricating brush penetrates through the disc and extends to the outside of the disc.

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