CN213323323U - Electric power steering device and screw nut assembly thereof - Google Patents

Abstract

The utility model discloses an electric power steering device and screw nut assembly thereof relates to power transmission technical field, establish the first nut on the screw rod including screw rod and cover, first nut periphery cover is equipped with the second nut, the cavity has between first nut and the second nut, the second nut be used for with the output shaft meshing. When the output shaft exerts the reaction force to the second nut, the second nut atress moves towards radial direction, because have the cavity between first nut and the second nut, makes the first nut that sets up in the inside of second nut can not receive the effect of radial force, avoids making the lead screw atress warp.

Description

Electric power steering device and screw nut assembly thereof

Technical Field

The utility model relates to a power transmission technical field, concretely relates to electric power steering device and screw nut assembly thereof.

Background

The electric steering gear of the recirculating ball is that a motor drives a steering screw nut to move up and down through a speed reducing mechanism, and the steering screw nut is converted into an output shaft to rotate so as to fulfill the aim of steering.

SUMMERY OF THE UTILITY MODEL

1. Technical problem to be solved by the utility model

The technical problem to radial force then can make the lead screw bending deformation that turns to, the utility model provides an electric power steering device and screw-nut assembly thereof, it makes to have the cavity between first nut and the second nut, makes to set up and can not receive the effect of radial force at the inside first nut of second nut, avoids making the lead screw atress warp.

2. Technical scheme

In order to solve the above problem, the utility model provides a technical scheme does: the utility model provides a screw nut assembly, includes the screw rod and establishes the first nut on the screw rod, first nut periphery cover is equipped with the second nut, have the cavity between first nut and the second nut, the second nut is used for with the output shaft meshing.

When the output shaft exerts the reaction force to the second nut, the second nut atress moves towards radial direction, because have the cavity between first nut and the second nut, makes the first nut that sets up in the inside of second nut can not receive the effect of radial force, avoids making the lead screw atress warp.

Optionally, the first nut includes first body and sets up the first limiting plate at first body both ends and perpendicular to first body, the second nut includes the second body and sets up the second limiting plate at second body both ends and perpendicular to second body, the lateral wall of first limiting plate supports each other with the inside wall of second limiting plate and leans on, the cavity has between first body and the second body.

Optionally, the second limiting plate at one end of the second body is detachably connected with the second body.

Optionally, the outer side wall of the second limiting plate and the inner side wall of the second body are both provided with threads, and the second limiting plate and the second body are matched through the threads.

Optionally, the first limiting plate and the second limiting plate are both provided with holes for the screw to pass through.

Optionally, a gear is arranged on one side of the second body, and the gear is used for being meshed with the output shaft.

Optionally, the screw rod includes a threaded section and smooth sections arranged at two ends of the threaded section, the first nut and the second nut are arranged on the threaded section, and the smooth sections are used for mounting the bearing.

Optionally, the threaded section and the smooth section are of an integrally formed structure.

Optionally, gear oil is used as a lubricant between the screw and the first nut.

The utility model also discloses an electric power steering device, establish bearing on the screw rod, with worm wheel complex worm, with second nut meshing's output shaft and the above including casing, worm wheel, cover the screw rod nut assembly, the worm wheel cover is established on the screw rod, screw rod nut assembly, worm wheel, worm and output shaft all set up inside the casing.

3. Advantageous effects

Adopt the technical scheme provided by the utility model, compare with prior art, have following beneficial effect:

(1) the screw nut assembly that this application embodiment provided, when the output shaft and applys reaction force to the second nut, the second nut atress moves towards radial direction, because have the cavity between first nut and the second nut, makes the setting can not receive the effect of radial force at the inside first nut of second nut, avoids making the lead screw atress warp.

Drawings

Fig. 1 is a schematic structural view of a screw nut assembly according to an embodiment of the present invention.

Fig. 2 is a schematic structural view of an electric power steering apparatus according to an embodiment of the present invention.

Detailed Description

For a further understanding of the present invention, reference will be made to the following detailed description taken in conjunction with the accompanying drawings and examples.

The present application will be described in further detail with reference to the following drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the relevant invention and are not limiting of the invention. It should be noted that, for convenience of description, only the portions related to the present invention are shown in the drawings. The utility model discloses in words such as first, second, be for the description the utility model discloses a technical scheme is convenient and set up, and does not have specific limiting action, is general finger, right the technical scheme of the utility model does not constitute limiting action. It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplification of description, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. Unless expressly stated or limited otherwise, the terms "mounted," "connected," and "connected" are intended to be inclusive and mean, for example, that they may be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art. The technical solutions in the same embodiment and between the technical solutions in different embodiments can be arranged and combined to form a new technical solution without contradiction or conflict, which is all within the scope of the present invention.

Example 1

With reference to fig. 1-2, the screw nut assembly of this embodiment includes a screw rod 1 and a first nut 2 sleeved on the screw rod 1, a second nut 3 is sleeved on the periphery of the first nut 2, a cavity 4 is provided between the first nut 2 and the second nut 3, and the second nut 3 is used for meshing with an output shaft 5. When the output shaft 5 exerts a reaction force on the second nut 3, the second nut 3 is stressed to move towards the radial direction, and the cavity 4 is arranged between the first nut 2 and the second nut 3, so that the first nut 2 arranged inside the second nut 3 cannot be stressed by the radial force, and the lead screw is prevented from being stressed and deformed.

Example 2

With reference to fig. 1-2, the screw nut assembly of the present embodiment can be improved as follows compared with the technical solution of embodiment 1: the first nut 2 comprises a first body 21 and a first limiting plate 22 which is arranged at two ends of the first body 21 and is perpendicular to the first body 21, the second nut 3 comprises a second body 31 and a second limiting plate 32 which is arranged at two ends of the second body 31 and is perpendicular to the second body 31, the outer side wall of the first limiting plate 22 is abutted against the inner side wall of the second limiting plate 32, and a cavity 4 is arranged between the first body 21 and the second body 31. The lateral wall of first limiting plate 22 supports with the inside wall of second limiting plate 32 each other and leans on, makes first nut 2 fix inside second nut 3, has avoided taking place axial displacement between first nut 2 and the second nut 3.

Example 3

With reference to fig. 1-2, the screw nut assembly of the present embodiment can be improved as follows compared with the technical solutions of embodiment 1 or 2: the second limiting plate 32 at one end of the second body 31 is detachably connected to the second body 31. When needs inspect first nut 2, dismantle the second limiting plate 32 of second nut 3 one end, even realize first nut 2 and the separation of second nut 3, be convenient for inspect first nut 2.

Example 4

With reference to fig. 1-2, the screw nut assembly of the present embodiment can be improved as follows compared with any of the technical solutions of embodiments 1-3: the outer side wall of the second limiting plate 32 and the inner side wall of the second body 31 are both provided with threads 321, and the second limiting plate 32 and the second body 31 are matched through the threads 321. When the limiting plate needs to be disassembled, the second limiting plate 32 and the second body 31 can be separated by unscrewing the threads 321, and the disassembly method is convenient and fast.

Example 5

With reference to fig. 1-2, the screw nut assembly of the present embodiment can be improved as follows compared with any of the technical solutions of embodiments 1-4: the first limiting plate 22 and the second limiting plate 32 are both provided with holes 221 for the screw 1 to pass through. The first nut 2 and the second nut 3 are sleeved on the screw rod 1 through the hole 221, so that the screw rod 1 drives the first nut 2 and the second nut 3 to rotate.

Example 6

With reference to fig. 1-2, the screw nut assembly of the present embodiment can be improved as follows compared with any of the technical solutions of embodiments 1-5: one side of the second body 31 is provided with a gear 311, and the gear 311 is used for being meshed with the output shaft 5. The second body 31 is meshed with the output shaft 5 through the gear 311, so that the output shaft is driven to rotate by the second nut 3.

Example 7

With reference to fig. 1-2, the screw nut assembly of the present embodiment can be improved as follows compared with any of the technical solutions of embodiments 1-6: the screw rod 1 comprises a threaded section 11 and smooth sections 12 arranged at two ends of the threaded section 11, the first nut 2 and the second nut 3 are arranged on the threaded section 11, and the smooth sections 12 are used for installing the bearing 6. In the use process, the output shaft 5 applies axial force to the second nut 3, the second nut 3 transmits the axial force to the bearings 6 at the two ends through the screw rod 1, the bearings 6 bear the axial force, and the screw rod 1 is prevented from being influenced.

Example 8

With reference to fig. 1-2, the screw nut assembly of the present embodiment can be improved as follows compared with any of the technical solutions of embodiments 1-7: the threaded section 11 and the smooth section 12 are of an integrally formed structure. The integrated structure makes the screw rod 1 a whole without any connection, and has stronger bearing capacity.

Example 9

With reference to fig. 1-2, the screw nut assembly of the present embodiment can be improved as follows compared with any of the technical solutions of embodiments 1-8: gear oil is adopted as a lubricant between the screw rod 1 and the first nut 2. The gear oil can greatly reduce the noise generated by the matching of the screw rod 1 and the first nut 2, and also can effectively reduce the heat generated by the rotation friction between the first nut 2 and the screw rod 1, thereby prolonging the service cycle.

Example 10

With reference to fig. 1-2, the electric power steering apparatus of the present embodiment includes a housing 7, a worm wheel 8, a bearing 6 sleeved on the screw rod 1, a worm 9 engaged with the worm wheel, an output shaft 5 engaged with the second nut 3, and the screw and nut assembly according to any one of embodiments 1-9, wherein the worm wheel 8 is sleeved on the screw rod 1, and the screw and nut assembly, the worm wheel 8, the worm 9, and the output shaft 5 are all disposed inside the housing 7.

The present invention and its embodiments have been described above schematically, and the description is not limited thereto, and what is shown in the drawings is only one of the embodiments of the present invention, and the actual structure is not limited thereto. Therefore, if the person skilled in the art receives the teaching of the present invention, without departing from the inventive spirit of the present invention, the person skilled in the art should also design the similar structural modes and embodiments without creativity to the technical solution, and all shall fall within the protection scope of the present invention.

Claims (10)

1. The screw and nut assembly is characterized by comprising a screw and a first nut sleeved on the screw, wherein a second nut is sleeved on the periphery of the first nut, a cavity is formed between the first nut and the second nut, and the second nut is used for being meshed with an output shaft.

2. The screw nut assembly according to claim 1, wherein the first nut includes a first body and a first limiting plate disposed at two ends of the first body and perpendicular to the first body, the second nut includes a second body and a second limiting plate disposed at two ends of the second body and perpendicular to the second body, an outer sidewall of the first limiting plate and an inner sidewall of the second limiting plate abut against each other, and a cavity is disposed between the first body and the second body.

3. The screw nut assembly of claim 2 wherein the second retainer plate at the one end of the second body is removably attached to the second body.

4. The screw nut assembly of claim 2 wherein the outer sidewall of the second retainer plate and the inner sidewall of the second body are both threaded, and the second retainer plate and the second body are engaged by the threads.

5. The screw nut assembly according to claim 2 wherein the first and second retainer plates each have a hole for the screw to pass through.

6. The screw nut assembly of claim 5 wherein the second body has a gear on one side for engaging the output shaft.

7. The screw nut assembly of claim 1 wherein the screw includes a threaded section and smooth sections at opposite ends of the threaded section, the first and second nuts being disposed in the threaded section, the smooth sections being configured to receive bearings.

8. The screw nut assembly of claim 7 wherein the threaded section and the smooth section are of one-piece construction.

9. A screw nut assembly according to any one of claims 1 to 8 in which gear oil is used as a lubricant between the screw and the first nut.

10. An electric power steering device is characterized by comprising a shell, a worm wheel, a bearing, a worm, an output shaft and a screw nut assembly, wherein the bearing is sleeved on a screw, the worm is matched with the worm wheel, the output shaft is meshed with a second nut, the screw nut assembly is arranged on the screw in a sleeved mode, and the screw nut assembly, the worm wheel, the worm and the output shaft are arranged inside the shell.

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