Gear shaft for automobile steering system

Abstract

The utility model provides a gear shaft for an automobile steering system, which comprises a gear shaft body, a plurality of helical teeth uniformly distributed in the circumferential direction of the gear shaft body are arranged on the outer wall of the lower part of the gear shaft body, the helical teeth are used for being meshed with racks in the automobile steering system, and a tooth groove is formed between every two adjacent helical teeth; an oil inlet channel with an opening in the upper end is axially formed in the gear shaft body, a plurality of oil outlet holes distributed at intervals in the circumferential direction are formed in the gear shaft body, each oil outlet hole extends in the radial direction of the gear shaft body, and the inner end of each oil outlet hole communicates with the lower end of the oil inlet channel. The outer end part of each oil outlet hole extends to the upper end of one tooth groove; according to the gear shaft, the gear shaft body and the rack can be lubricated under the condition that the gear shaft body is not dismantled, and therefore convenience can be brought to lubrication of the gear shaft body and the rack.

Description

Technical Field

[0001] The utility model relates to the technical field of automobile parts, in particular to a gear shaft for an automobile steering system. Background Art

[0002] The gear shaft is an important transmission component in the automobile steering system. Its function is to connect the steering shaft and the rack in the automobile steering system. When in use, the gear shaft is installed at the inner bottom of the steering gear housing, and the helical teeth on the outer peripheral wall of the gear shaft are engaged with the rack, and the upper end of the gear shaft is rotatably connected to the steering shaft. During the long-term use of the automobile steering system, the lubrication performance between the helical teeth on the outer peripheral wall of the gear shaft and the rack will decrease. For this reason, when the automobile is repaired, it is necessary to add lubricating oil between the helical teeth of the gear shaft and the rack. However, since the gear shaft is installed at the inner bottom of the steering gear housing, when it is necessary to add lubricating oil between the helical teeth of the gear shaft and the rack, the gear shaft needs to be removed from the steering gear housing, which has the disadvantage of being troublesome to add lubricating oil. Utility Model Content

[0003] The technical problem to be solved by the utility model is to provide a gear shaft for an automobile steering system, which can realize lubrication of the gear shaft body and the rack without removing the gear shaft body, thereby bringing convenience to the lubrication of the gear shaft body and the rack.

[0004] The utility model provides a gear shaft for an automobile steering system, comprising a gear shaft body, wherein the outer wall of the lower portion of the gear shaft body is provided with a plurality of spiral teeth uniformly distributed around the circumference of the gear shaft body, the spiral teeth being used to mesh with a rack in the automobile steering system, and tooth grooves being formed between every two adjacent spiral teeth; an oil inlet passage with an upper end opening is axially provided inside the gear shaft body, and the gear shaft body is provided with a plurality of oil outlet holes distributed at intervals in the circumferential direction, each oil outlet hole extending in the radial direction of the gear shaft body, the inner end portion of each oil outlet hole being communicated with the lower end of the oil inlet passage, and the outer end portion of each oil outlet hole extending to the upper end of one of the tooth grooves.

[0005] After adopting the above structure, the utility model has the following advantages: when it is necessary to add lubricating oil between the helical teeth and the rack of the gear shaft, it is only necessary to separate the upper end of the gear shaft body from the steering shaft, and then add lubricating oil to the tooth groove through the oil inlet channel and the oil outlet hole to lubricate the helical teeth and the rack, that is, the gear shaft body and the rack can be lubricated without removing the gear shaft body, thereby facilitating the lubrication of the gear shaft body and the rack. After the lubricating oil is added, the upper end of the gear shaft body can be connected to the lower end of the steering shaft.

[0006] In one possible embodiment, a circular cylinder having an outer diameter smaller than that of the gear shaft body is provided at the lower end of the gear shaft body. The circular cylinder is coaxially arranged with the gear shaft body and is configured to be inserted into the inner hole of a needle roller bearing installed in the steering system of an automobile. A first annular conical surface is provided on the outer wall of the lower end of the circular cylinder. The first annular conical surface is configured to cooperate with the inner wall of the inner hole of the needle roller bearing to guide the circular cylinder to facilitate insertion of the circular cylinder into the inner hole of the needle roller bearing. With this structure, after the circular cylinder is inserted into the inner hole of the needle roller bearing installed in the steering system of the automobile, the gear shaft body can be smoothly rotatably connected to the housing of the steering system of the automobile, thereby reducing rotational friction between the gear shaft body and the housing of the steering system of the automobile. Moreover, since the first annular conical surface is provided on the outer wall of the lower end of the circular cylinder, during the process of inserting the circular cylinder into the inner hole of the needle roller bearing, the first annular conical surface can cooperate with the inner wall of the inner hole of the needle roller bearing to guide the circular cylinder into the inner hole of the needle roller bearing, thereby facilitating the insertion of the circular cylinder into the inner hole of the needle roller bearing.

[0007] In one possible embodiment, spline teeth are circumferentially provided on the outer wall of the upper part of the gear shaft body, and the upper end of the gear shaft body is used to be inserted into the lower end of the steering shaft, and the spline teeth are used to engage with the key groove on the inner wall of the lower end of the steering shaft and limit the position circumferentially; by adopting this structure, after the upper end of the gear shaft body is inserted into the lower end of the steering shaft, the spline teeth can engage with the key groove on the inner wall of the lower end of the steering shaft and limit the position circumferentially, so that the steering shaft connected to the steering wheel can reliably drive the gear shaft to rotate.

[0008] In one possible embodiment, an annular boss is provided on the outer wall of the gear shaft body below the spline teeth, and the annular boss is used to abut against the lower end of the steering shaft; after the annular boss is provided on the outer wall of the gear shaft body below the spline teeth, after the upper end of the gear shaft body and the lower end of the steering shaft are fitted and plugged in, the annular boss can abut against the lower end of the steering shaft, thereby achieving the limitation of the gear shaft body and the steering shaft, and the annular boss can play a supporting role for the steering shaft, thereby improving the reliability of the connection between the gear shaft body and the steering shaft.

[0009] In one possible embodiment, a second annular conical surface is provided on the outer wall of the upper end of the gear shaft body, and the second annular conical surface is used to cooperate and guide with the inner wall of the lower end of the steering shaft to facilitate the insertion of the upper end of the gear shaft body into the lower end of the steering shaft; after the second annular conical surface is provided on the outer wall of the upper end of the gear shaft body, when the upper end of the gear shaft body and the lower end of the steering shaft are cooperated and plugged in, the second annular conical surface can cooperate and guide with the inner wall of the lower end of the steering shaft to facilitate the insertion of the upper end of the gear shaft body into the lower end of the steering shaft, which can facilitate the connection between the gear shaft body and the steering shaft. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a schematic diagram of the three-dimensional structure of the utility model;

[0011] Figure 2 This is a schematic cross-sectional view of the utility model;

[0012] Figure 3 for Figure 2 Schematic diagram of the structure after enlarging point A in the middle. DETAILED DESCRIPTION

[0013] First, those skilled in the art should understand that these embodiments are merely used to explain the technical principles of the embodiments of the present application and are not intended to limit the scope of protection of the embodiments of the present application. Those skilled in the art may adjust them as needed to suit specific application scenarios.

[0014] In the description of the embodiments of this application, it should be noted that, unless otherwise specified or limited, the terms "connected" and "connection" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium. Those skilled in the art will understand the specific meanings of the above terms in the embodiments of this application based on the specific circumstances.

[0015] In the embodiments of the present application, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, a first feature being "above," "above," and "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0016] The present application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0017] See also Figure 1-3As shown, the embodiment of the present application discloses a gear shaft for an automobile steering system, including a gear shaft body 1. The outer wall of the lower part of the gear shaft body 1 is provided with a plurality of helical teeth 11 uniformly distributed around the circumference of the gear shaft body 1. The helical teeth 11 are used to engage with the rack in the automobile steering system, and a tooth groove 12 is formed between each adjacent two helical teeth 11; an oil inlet channel 13 with an upper end opening is axially provided inside the gear shaft body 1, and a plurality of oil outlet holes 14 distributed at circumferential intervals are provided on the gear shaft body 1. Each oil outlet hole 14 extends along the radial direction of the gear shaft body 1, and the inner end portion of each oil outlet hole 14 is connected to the lower end of the oil inlet channel 13, and the outer end portion of each oil outlet hole 14 extends to the upper end of one of the tooth grooves 12.

[0018] The lower end of the gear shaft body 1 is provided with a circular cylinder 15 having an outer diameter smaller than that of the gear shaft body 1. The circular cylinder 15 is coaxially arranged with the gear shaft body 1. The circular cylinder 15 is used to be inserted into the inner hole of the needle roller bearing installed in the steering system of the automobile. The outer wall of the lower end of the circular cylinder 15 is provided with a first annular conical surface 16. The first annular conical surface 16 is used to cooperate with the inner wall of the inner hole of the needle roller bearing to guide the circular cylinder 15 to be inserted into the inner hole of the needle roller bearing. After adopting this structure, when the circular cylinder is inserted into the inner hole of the needle roller bearing installed in the steering system of the automobile, the circular cylinder 15 is inserted into the inner hole of the needle roller bearing. After the circular cylinder is inserted into the inner hole of the needle roller bearing, the gear shaft body can be smoothly connected to the housing in the automobile steering system to reduce the rotational friction between the gear shaft body and the housing in the automobile steering system; and because a first annular conical surface is provided on the outer wall of the lower end of the circular cylinder, during the process of inserting the circular cylinder into the inner hole of the needle roller bearing, the first annular conical surface can cooperate with the inner wall of the inner hole of the needle roller bearing to guide the circular cylinder to be inserted into the inner hole of the needle roller bearing, that is, it can bring convenience to the process of inserting the circular cylinder into the inner hole of the needle roller bearing.

[0019] Spline teeth 17 are circumferentially arranged on the outer wall of the upper part of the gear shaft body 1. The upper end of the gear shaft body 1 is used to be inserted into the lower end of the steering shaft, and the spline teeth 17 are used to engage with the keyway on the inner wall of the lower end of the steering shaft and limit the position circumferentially. After adopting this structure, after the upper end of the gear shaft body is inserted into the lower end of the steering shaft, the spline teeth can engage with the keyway on the inner wall of the lower end of the steering shaft and limit the position circumferentially, so that the steering shaft connected to the steering wheel can reliably drive the gear shaft to rotate.

[0020] An annular boss 18 is provided on the outer wall of the gear shaft body 1 below the spline teeth 17, and the annular boss 18 is used to abut against the lower end of the steering shaft; by providing the annular boss on the outer wall of the gear shaft body below the spline teeth, after the upper end of the gear shaft body and the lower end of the steering shaft are fitted and plugged in, the annular boss can abut against the lower end of the steering shaft, thereby achieving the limitation of the gear shaft body and the steering shaft, and the annular boss can play a supporting role for the steering shaft, thereby improving the reliability of the connection between the gear shaft body and the steering shaft.

[0021] A second annular conical surface 19 is provided on the outer wall of the upper end of the gear shaft body 1, and the second annular conical surface 19 is used to cooperate and guide with the inner wall of the lower end of the steering shaft so that the upper end of the gear shaft body 1 is inserted into the lower end of the steering shaft; after the second annular conical surface is provided on the outer wall of the upper end of the gear shaft body, when the upper end of the gear shaft body and the lower end of the steering shaft are cooperated and plugged in, the second annular conical surface can cooperate and guide with the inner wall of the lower end of the steering shaft so that the upper end of the gear shaft body is inserted into the lower end of the steering shaft, which can facilitate the connection between the gear shaft body and the steering shaft.

[0022] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A gear shaft for an automobile steering system, comprising a gear shaft body (1), wherein a plurality of helical teeth (11) are arranged on the outer wall of the lower portion of the gear shaft body (1) and are evenly distributed around the circumference of the gear shaft body (1), wherein the helical teeth (11) are used to mesh with a rack in the automobile steering system, and a tooth groove (12) is formed between each two adjacent helical teeth (11); and characterized in that: An oil inlet passage (13) with an upper opening is axially provided inside the gear shaft body (1), and a plurality of oil outlet holes (14) are provided on the gear shaft body (1) and are distributed at intervals in the circumferential direction. Each of the oil outlet holes (14) extends in the radial direction of the gear shaft body (1), and the inner end of each of the oil outlet holes (14) is communicated with the lower end of the oil inlet passage (13), and the outer end of each of the oil outlet holes (14) extends to the upper end of one of the tooth grooves (12).

2. The gear shaft for an automobile steering system according to claim 1, characterized in that: The lower end of the gear shaft body (1) is provided with a circular cylinder (15) having an outer diameter smaller than that of the gear shaft body (1), the circular cylinder (15) being coaxially arranged with the gear shaft body (1), and the circular cylinder (15) being used to be inserted into the inner hole of a needle roller bearing installed in the steering system of an automobile, and the outer wall of the lower end of the circular cylinder (15) is provided with a first annular conical surface (16), and the first annular conical surface (16) is used to cooperate with the inner wall of the inner hole of the needle roller bearing for guiding so as to facilitate the circular cylinder (15) to be inserted into the inner hole of the needle roller bearing.

3. The gear shaft for an automobile steering system according to claim 1 or 2, characterized in that: Spline teeth (17) are circumferentially provided on the outer wall of the upper portion of the gear shaft body (1); the upper end of the gear shaft body (1) is used to be inserted into the lower end of the steering shaft; the spline teeth (17) are used to engage with the keyway on the inner wall of the lower end of the steering shaft and limit the position circumferentially.

4. The gear shaft for an automobile steering system according to claim 3, characterized in that: An annular boss (18) is provided on the outer wall of the gear shaft body (1) below the spline teeth (17), and the annular boss (18) is used to abut against the lower end of the steering shaft.

5. The gear shaft for an automobile steering system according to claim 3, characterized in that: A second annular conical surface (19) is provided on the outer wall of the upper end of the gear shaft body (1), and the second annular conical surface (19) is used to cooperate with the inner wall of the lower end of the steering shaft () for guidance so that the upper end of the gear shaft body (1) can be inserted into the lower end of the steering shaft.

Images