Electric steering gear and vehicle

Abstract

The utility model discloses an electric steering gear and a vehicle. The electric steering gear comprises a shell; the steering rod is arranged in the shell and movably connected with the shell, and the steering rod is provided with a rack part and a lead screw part; the input shaft is in transmission connection with the rack part and is used for driving the steering rod to move; the ball nut is arranged outside the lead screw part in a sleeving mode and matched with the lead screw part, the ball nut is rotatably connected with the shell, the driving motor is arranged on the shell and suitable for driving the ball nut to rotate so as to drive the steering rod to move, and the speed reducing mechanism comprises a first gear and a second gear; the first gear is connected with the ball nut, the second gear is connected with an output shaft of the driving motor, and the first gear is meshed with the second gear. According to the electric steering gear, gear transmission between the driving motor and the ball nut can be achieved, the working stability of the electric steering gear is improved, and the operation experience of a driver is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of vehicle steering gears, in particular to an electric steering gear and a vehicle. Background Art

[0002] In the related technology, traditional electric steering gears are generally driven by belts, but the consistency of the belt tension is difficult to control and the belts are prone to slipping, resulting in poor accuracy in torque transmission within the electric steering gear and affecting the consistency of its no-load rotational torque. At the same time, electric steering gears with belt drive may also have problems such as belt breakage or motor shaft breakage during operation, causing the steering system to easily lose the power assistance of the motor, reducing the stability of the electric steering gear and affecting the driver's operating experience. There is room for improvement. Utility Model Content

[0003] The utility model aims to solve at least one of the technical problems existing in the prior art. To this end, one purpose of the utility model is to provide an electric steering gear, which has high working stability and can improve the driver's operating experience.

[0004] The utility model also provides a vehicle.

[0005] According to the first aspect of the utility model, the electric steering gear comprises: a housing; a steering rod, the steering rod is arranged in the housing and movably connected to the housing, the steering rod has a rack portion and a screw portion; an input shaft, the input shaft is drivingly connected to the rack portion to drive the steering rod to move; a ball nut, the ball nut is sleeved outside the screw portion and cooperates with the screw portion, the ball nut is rotatably connected to the housing, a driving motor, the driving motor is arranged on the housing, the driving motor is suitable for driving the ball nut to rotate to drive the steering rod to move, and a reduction mechanism, the reduction mechanism comprises a first gear and a second gear, the first gear is connected to the ball nut, the second gear is connected to the output shaft of the driving motor, the first gear is meshed with the second gear, and the rotation axis of the first gear is parallel to the rotation axis of the second gear, and the reduction mechanism is configured to increase the torque of the driving motor to drive the steering rod to move, wherein the top circle diameter of the first gear is larger than the top circle diameter of the second gear.

[0006] According to the electric steering gear of the embodiment of the utility model, by setting the first gear on the ball nut and setting the second gear on the output shaft of the drive motor, and the second gear and the first gear are meshed, gear transmission between the drive motor and the ball nut can be realized, the accuracy of torque transmission to the output shaft of the drive motor can be improved, the consistency of no-load rotation torque of the electric steering gear can be improved, the stability of the operation of the electric steering gear can be improved, and the driver's operating experience can be improved; in addition, by driving the first gear with the second gear, and the first gear is larger than the second gear, the torque output of the reduction mechanism can be increased, the driving force on the steering rod can be increased, and the power assistance effect on the input shaft can be improved, which can save the driver's physical strength. At the same time, the speed output of the reduction mechanism can be reduced to reduce the activity speed of the steering rod, prevent the steering rod from driving the input shaft to rotate, and improve the driving safety of the driver.

[0007] According to some embodiments of the present invention, the first gear sleeve is disposed outside the ball nut and has an interference fit with the ball nut.

[0008] In some examples, the electric steering gear further includes: a bearing, wherein the bearing is sleeved outside the ball nut, an inner ring of the bearing and the ball nut are interference fit, and an outer ring of the bearing is connected to the housing.

[0009] In some examples, in the extension direction of the ball nut, the bearing and the first gear are coaxially arranged and opposite to each other.

[0010] In some examples, the first gear is disposed at an end of the ball nut, and in the axial direction of the second gear, the drive motor is disposed on a side of the first gear close to the bearing.

[0011] According to some embodiments of the present invention, the second gear sleeve is disposed outside the output shaft and has an interference fit with the output shaft.

[0012] According to some embodiments of the present invention, the tooth top circle diameter of the first gear is greater than the tooth top circle diameter of the second gear, and / or the number of teeth of the first gear is greater than the number of teeth of the second gear.

[0013] In some examples, the electric steering gear further includes: a controller, which is electrically connected to the electronic control unit of the vehicle and the drive motor, respectively, and the controller can control the drive motor to execute the target torque and speed according to the power output torque calculated by the electronic control unit.

[0014] In some examples, the electric steering gear further includes: a plurality of sensors, each of which is electrically connected to an electronic control unit of the vehicle to detect a vehicle speed signal and a torque signal of the output shaft and transmit the signals to the electronic control unit.

[0015] The vehicle according to the second aspect embodiment of the utility model includes the electric steering gear according to the first aspect embodiment of the utility model. By adopting the above-mentioned electric steering gear, gear transmission between the drive motor and the ball nut can be realized, thereby ensuring the consistency of the no-load rotational torque of the electric steering gear, improving the working stability of the electric steering gear, and improving the steering stability of the vehicle.

[0016] Additional aspects and advantages of the present invention will be given in part in the following description, and in part will become apparent from the following description, or will be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0018] Figure 1 is a schematic structural diagram of an electric steering gear according to some embodiments of the utility model;

[0019] Figure 2 It is a schematic diagram of the partial structure of an electric steering gear according to some embodiments of the utility model.

[0020] Reference numerals:

[0021] Electric steering gear 100,

[0022] Housing 10,

[0023] Steering rod 20, screw part 21,

[0024] Input shaft 30, ball nut 40, drive motor 50,

[0025] Speed ​​reduction mechanism 60, first gear 61, second gear 62,

[0026] Bearing 70, tie rod 80. DETAILED DESCRIPTION

[0027] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0028] In the description of the present utility model, it is necessary to understand that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present utility model 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 utility model. In addition, features defined as "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present utility model, unless otherwise specified, "multiple" means two or more.

[0029] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" 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 indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0030] Reference below Figure 1-Figure 2 An electric power steering gear 100 according to an embodiment of the present invention is described.

[0031] like Figure 1-Figure 2 As shown, the electric steering gear 100 according to the embodiment of the utility model includes: a housing 10, a steering rod 20, an input shaft 30, a ball nut 40, a drive motor 50 and a reduction mechanism 60. The steering rod 20 is arranged in the housing 10, and the steering rod 20 is movably connected to the housing 10. The steering rod 20 has a rack portion and a screw portion 21. The input shaft 30 and the rack portion are transmission-connected to drive the steering rod 20 to move.

[0032] The ball nut 40 is sleeved outside the screw part 21, and the ball nut 40 cooperates with the screw part 21. The ball nut 40 is rotatably connected to the housing 10, so that the ball nut 40 can rotate relative to the screw part 21 to drive the screw part 21 to move along the axial direction of the steering rod 20 (such as Figure 2Specifically, a return guide device may be provided outside the ball nut 40, so that a closed spiral channel can be formed between the ball nut 40 and the screw portion 21, and a plurality of balls can be filled in the spiral channel. When the ball nut 40 and the screw portion 21 rotate relative to each other, the plurality of balls can circulate and roll along the spiral channel, thereby reducing the friction between the ball nut 40 and the screw portion 21 and improving the smoothness of the movement of the steering rod 20.

[0033] The drive motor 50 is arranged on the housing 10. The drive motor 50 can drive the ball nut 40 to rotate, so as to drive the steering rod 20 to move, and can provide assistance for the input shaft 30; the drive motor 50 drives the ball nut 40 to rotate through the reduction mechanism 60, and the reduction mechanism 60 includes a first gear 61 and a second gear 62. The first gear 61 is connected to the ball nut 40, and the second gear 62 is connected to the output shaft of the drive motor 50, and the first gear 61 is meshed with the second gear 62, that is, the drive motor 50 drives the ball nut 40 to rotate through the transmission of gears, which can improve the accuracy of torque transmission to the output shaft of the drive motor 50, and can improve the consistency of the no-load rotation torque of the electric steering gear 100, that is, ensure the consistency of the no-load friction force of the electric steering gear 100, improve the working stability of the electric steering gear 100, and improve the driver's operating experience.

[0034] The rotation axis of the first gear 61 and the rotation axis of the second gear 62 are parallel to each other, so that the axial direction of the output shaft of the driving motor 50 is parallel to the axial direction of the steering rod 20 (such as Figure 1 The left and right directions shown in FIG. 1 are beneficial for the drive motor 50 to fully utilize the lateral direction of the electric steering gear 100 (such as Figure 1 The left and right directions (as shown) space can save space, realize the miniaturization of the electric steering gear 100, and facilitate layout.

[0035] Among them, the tooth top circle diameter of the first gear 61 is larger than the tooth top circle diameter of the second gear 62, so that the reduction mechanism 60 can amplify the torque of the output shaft of the drive motor 50 to drive the steering rod 20 to move, that is, when the first gear 61 and the second gear 62 rotate synchronously, the torque of the first gear 61 is greater than the torque of the second gear, and the first gear 61 is driven by the second gear 62, which can increase the torque output of the reduction mechanism 60, increase the driving force on the steering rod 20, and improve the power assistance effect on the input shaft 30, which can save the driver's physical strength and improve the driver's operating experience.

[0036] At the same time, the first gear 61 is driven by the second gear 62, so that the rotational angular velocity of the first gear 61 is smaller than the rotational angular velocity of the second gear 62. Since the steering rod 20 and the first gear 62 rotate at the same angular velocity, the speed output of the reduction mechanism 60 can be reduced to reduce the moving speed of the steering rod 20, thereby preventing the moving speed of the screw part 21 from being greater than the moving speed of the rack part, and preventing the steering rod 20 from driving the input shaft 30 to rotate. The power assist effect on the input shaft 30 can be improved, thereby improving the driver's operating experience and improving the driver's driving safety.

[0037] According to the electric steering gear 100 of the embodiment of the utility model, by setting a first gear 61 on the ball nut 40, and by setting a second gear 62 on the output shaft of the drive motor 50, and the second gear 62 and the first gear 61 are meshed, it is possible to realize gear transmission between the drive motor 50 and the ball nut 40, improve the accuracy of torque transmission to the output shaft of the drive motor 50, improve the consistency of the no-load rotational torque of the electric steering gear 100, improve the working stability of the electric steering gear 100, and improve the driver's operating experience.

[0038] In addition, by driving the first gear 61 through the second gear 62, and the first gear 61 is larger than the second gear 62, the torque output of the reduction mechanism 60 can be increased, the driving force on the steering rod 20 can be increased, and the assist effect on the input shaft 30 can be improved, which can save the driver's physical strength. At the same time, the speed output of the reduction mechanism 60 can be reduced to reduce the movement speed of the steering rod 20, prevent the steering rod 20 from driving the input shaft 30 to rotate, and improve the driver's driving safety.

[0039] like Figure 2 As shown, according to some embodiments of the utility model, the first gear 61 can be sleeved on the outside of the ball nut 40, and the first gear 61 can be interference fit with the ball nut 40, so that the rotation of the first gear 61 can drive the ball nut 40 to rotate, and the probability of relative sliding between the first gear 61 and the ball nut 40 can be reduced, which is beneficial to improving the transmission efficiency of the electric steering gear 100, improving the power assist effect on the input shaft 30, and improving the driver's operating experience; of course, the first gear 61 can be integrally formed with the ball nut 40, or the first gear 61 is connected to the ball nut 40 by a fastener, which can improve the structural strength of the connection between the first gear 61 and the ball nut 40, improve the service life of the electric steering gear 100, and facilitate maintenance.

[0040] like Figure 2As shown, in some examples, the electric steering gear 100 further includes: a bearing 70, the bearing 70 can be sleeved outside the ball nut 40, the inner ring of the bearing 70 and the ball nut 40 are interference fit, so that the inner ring of the bearing 70 and the ball nut 40 can rotate together, and the outer ring of the bearing 70 and the housing 10 can be connected by a fastener. On the one hand, the connection between the ball nut 40 and the housing 10 can be achieved, that is, on the basis that the driving motor 50 can drive the ball nut 40 to rotate normally, the ball nut 40 can be prevented from rotating along the extension direction of the steering rod 20 (such as Figure 1 On the other hand, the bearing 70 can support the ball nut 40, which is beneficial to improve the rotation stability of the ball nut 40 and the working stability of the electric steering gear 100.

[0041] like Figure 2 As shown, in some examples, in the extension direction of the ball nut 40 (such as Figure 2 In the left and right directions shown in the figure, the bearing 70 and the first gear 61 are coaxially arranged, which can ensure the normal rotation of the ball nut 40 and improve the stability of the rotation of the ball nut 40; the bearing 70 and the first gear 61 are relatively positioned, which can increase the distance between the reduction mechanism 60 and the bearing 70, and prevent the reduction mechanism 60 from interfering with the bearing 70 during the rotation of the ball nut 40, which is beneficial to improving the reliability of the electric steering gear 100.

[0042] like Figure 2 As shown, in some examples, the first gear 61 is disposed at the end of the ball nut 40 (eg Figure 2 The right end shown in FIG. 1 is in the axial direction of the second gear 62 (as shown in FIG. Figure 2 The drive motor 50 is arranged on one side of the first gear 61 close to the bearing 70 (as shown in the left and right directions). Figure 2 As shown in the left side, based on preventing the interference between the driving motor 50 and the ball nut 40, the structure of the electric steering gear 100 can be made more compact and convenient for layout.

[0043] like Figure 2 As shown, according to some embodiments of the utility model, the second gear 62 can be sleeved on the output shaft of the drive motor 50, and the second gear 62 can be interference fit with the output shaft, so that the rotation of the output shaft can drive the second gear 62 to rotate, and the probability of relative sliding between the second gear 62 and the output shaft can be reduced, which is beneficial to improving the transmission efficiency of the electric steering gear 100, and then the power assist effect on the input shaft 30 can be improved, and the driver's operating experience can be improved; of course, the second gear 62 can be integrally formed with the output shaft, which can improve the structural strength of the connection between the second gear 62 and the output shaft, improve the service life of the electric steering gear 100, and facilitate maintenance.

[0044] like Figure 2 As shown, according to some embodiments of the utility model, the first gear 61 and the second gear 62 are meshed, that is, the gear teeth on the first gear 61 and the gear teeth on the second gear 62 are the same size, wherein the top circle diameter of the first gear 61 is larger than the top circle diameter of the second gear 62, that is, the number of teeth of the first gear 61 is greater than the number of teeth of the second gear 62, and since the second gear 62 is the driving wheel and the first gear 61 is the driven wheel, the transmission ratio of the reduction mechanism 60 can be increased, and the torque of the ball nut 40 can be increased and the rotation speed of the ball nut 40 can be reduced on the basis of the unchanged rotation speed of the output shaft of the drive motor 50.

[0045] On the one hand, the driving force on the steering rod 20 can be increased, the assist effect on the input shaft 30 can be improved, and the smoothness of the movement of the steering rod 20 can be improved, making the steering of the wheels easier and more convenient for the driver to operate. On the other hand, the movement speed of the screw part 21 can be ensured to be lower than the movement speed of the rack part, preventing the steering rod 20 from driving the steering wheel to rotate through the input shaft 30, thereby improving the safety of the occupants.

[0046] In some examples, the electric steering gear 100 also includes: multiple sensors, each of which is electrically connected to the vehicle's electronic control unit (ECU), and the sensor can be set on the input shaft 30 to detect the torque signal of the output shaft. The sensor can also be set on the wheel to detect the vehicle speed signal, that is, the multiple sensors can be set at multiple locations in the vehicle to detect various data signals of the vehicle's driving and transmit the above signals to the electronic control unit for analysis and calculation by the electronic control unit.

[0047] In some examples, the electric steering gear 100 also includes: a controller, which is electrically connected to the vehicle's electronic control unit (ECU) and the drive motor 50, respectively. The controller can control the drive motor 50 to execute the target torque and speed based on the power-assist output torque calculated by the electronic control unit, thereby ensuring the timeliness of the electric steering gear 100 assisting the input shaft 30, which is beneficial to improving the assisting effect on the input shaft 30 and improving the driver's driving experience.

[0048] like Figure 1 As shown, in some examples, the electric steering gear 100 further includes: two tie rods 80, which are respectively arranged at both ends of the steering rod 20 (such as Figure 1 The left and right ends shown in the figure) and the two pull rods 80 are movably connected to the two ends of the steering rod 20, and the input shaft 30 cooperates with the drive motor 50 to drive the steering rod 20 along its own axial direction (such as Figure 1 The steering rod 20 moves in the left and right directions as shown, and then the steering rod 20 pulls the wheel through the pull rod 80 to drive the wheel to rotate, thereby realizing the steering of the vehicle.

[0049] According to the vehicle of the embodiment of the utility model, the electric steering gear 100 is included. By adopting the above-mentioned electric steering gear 100, the gear transmission between the drive motor 50 and the ball nut 40 can be realized, thereby ensuring the consistency of the no-load rotation torque of the electric steering gear 100, improving the working stability of the electric steering gear 100, and improving the steering stability of the vehicle.

[0050] Other components and operations of the vehicle according to the embodiment of the utility model are known to those skilled in the art and will not be described in detail here. In the description of the utility model, "first feature" and "second feature" may include one or more of the features. Among them, the up-down direction, left-right direction and front-back direction are based on the up-down direction, left-right direction and front-back direction shown in the figure.

[0051] In the description of the present utility model, unless otherwise clearly specified and limited, a first feature "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature "above", "above" and "above" a second feature include that the first feature is directly above and obliquely above the second feature, or simply means that the first feature is higher in level than the second feature.

[0052] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0053] Although the embodiments of the present invention have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. An electric steering gear, characterized in that: include: case; A steering rod, the steering rod is arranged in the housing and movably connected to the housing, and the steering rod has a rack portion and a screw portion; An input shaft, the input shaft is drivingly connected to the rack portion to drive the steering rod to move; A ball nut, the ball nut is sleeved outside the screw part and cooperates with the screw part, and the ball nut is rotatably connected to the housing, A driving motor, wherein the driving motor is arranged on the housing and is suitable for driving the ball nut to rotate so as to drive the steering rod to move. A reduction mechanism, the reduction mechanism comprising a first gear and a second gear, the first gear being connected to the ball nut, the second gear being connected to the output shaft of the drive motor, the first gear being meshed with the second gear, and the rotation axis of the first gear and the rotation axis of the second gear being parallel to each other, the reduction mechanism being configured to increase the torque of the drive motor to drive the steering rod to move, Wherein, the tooth top circle diameter of the first gear is greater than the tooth top circle diameter of the second gear.

2. The electric steering gear according to claim 1, characterized in that: The first gear sleeve is arranged outside the ball nut and is interference fit with the ball nut.

3. The electric steering gear according to claim 2, characterized in that: Also includes: The bearing is sleeved outside the ball nut, the inner ring of the bearing and the ball nut are interference fit, and the outer ring of the bearing is connected to the housing.

4. The electric steering gear according to claim 3, characterized in that: In the extending direction of the ball nut, the bearing and the first gear are coaxially arranged and opposite to each other.

5. The electric steering gear according to claim 4, characterized in that: The first gear is arranged at the end of the ball nut, and in the axial direction of the second gear, the driving motor is arranged at a side of the first gear close to the bearing.

6. The electric power steering gear according to claim 1, characterized in that: The second gear sleeve is arranged outside the output shaft and is interference fit with the output shaft.

7. The electric steering gear according to any one of claims 1 to 6, characterized in that: Also includes: A controller is electrically connected to the electronic control unit of the vehicle and the drive motor respectively, and the controller can control the drive motor to execute the target torque and speed according to the power output torque calculated by the electronic control unit.

8. The electric power steering gear according to claim 7, characterized in that: Also includes: A plurality of sensors are electrically connected to an electronic control unit of the vehicle respectively, and are used to detect a vehicle speed signal and a torque signal of the output shaft and transmit the signals to the electronic control unit.

9. A vehicle, characterized in that: It comprises an electric steering gear according to any one of claims 1-8.

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