Steering shaft for a vehicle steering gear

Abstract

The utility model discloses a kind of steering shafts for automobile steering gear, including steering shaft, the shaft body of steering shaft is equipped with protective sleeve, the both ends of steering shaft are equipped with lubricating cylinder;The protective sleeve includes heat-absorbing part, the outer surface of heat-absorbing part is sleeved with sleeve body, the outer surface of sleeve body is opened with several equidistant distribution's spline groove, the sleeve body is sleeved in the outside of steering shaft;The setting of this steering shaft for automobile steering gear, structure design is reasonable, the protective sleeve of steering shaft shaft body place assembly in the utility model, its internal heat-absorbing part includes heat-absorbing shaft, heat-conducting strip and heat-conducting ring, can quickly absorb the heat generated by steering shaft operation, and heat is conducted diffusion by heat-conducting strip and heat-conducting ring, effectively reduce the temperature of steering shaft, avoid the material performance decline and wear aggravation due to high temperature, greatly improve the service life and reliability of steering shaft.

Description

Technical Field

[0001] This utility model relates to the field of steering shaft technology, specifically a steering shaft for automobile steering systems. Background Technology

[0002] In automotive steering systems, the steering shaft is a critical component, and its performance directly affects the vehicle's handling stability and safety. Existing steering shafts for automotive steering systems present numerous problems in practical use. Firstly, during long-term operation, the shaft body easily generates significant heat due to friction. Traditional steering shafts lack effective heat dissipation structures, and excessively high temperatures lead to a decline in the material properties of the steering shaft, accelerating wear and affecting its lifespan and the reliability of the steering system. Secondly, when the two ends of the steering shaft rotate in connection with other components, lubrication is inadequate. Existing lubrication structures struggle to achieve continuous and efficient lubrication, increasing rotational resistance. This not only increases the driver's workload but also causes excessive wear on components, increasing maintenance costs. Furthermore, the assembly and connection structure of the steering shaft also has shortcomings. Traditional connection methods are cumbersome to install and disassemble, and the stability and sealing of the connection are difficult to guarantee, easily leading to loosening and oil leaks, affecting the normal operation of the steering system. Therefore, there is an urgent need to design a new steering shaft for automotive steering systems to solve the problems existing in the current technology. Utility Model Content

[0003] The purpose of this invention is to provide a steering shaft for an automobile steering system to solve the problems mentioned in the background art.

[0004] To achieve the above objectives, this utility model provides the following technical solution: a steering shaft for an automotive steering system, comprising a steering shaft, a protective bushing mounted on the shaft body, and lubrication cylinders mounted on both ends of the steering shaft; the protective bushing includes a heat-absorbing element, a sleeve body fitted onto the outer surface of the heat-absorbing element, and a plurality of equally spaced spline grooves on the outer surface of the sleeve body, the sleeve body being fitted onto the outside of the steering shaft; the lubrication cylinder includes a shaft cylinder a and a shaft cylinder b arranged opposite to each other, and connecting plates are installed on the outer walls of both sides of shaft cylinder a and shaft cylinder b; threaded holes are provided on the side walls of the two connecting plates on the left and right sides, and bolts are screwed into the threaded holes.

[0005] As a preferred embodiment of the present invention, the inner walls of the shaft cylinders a and b are provided with rotating cavities evenly spaced along their axis, and ball bearings are installed inside the rotating cavities.

[0006] As a preferred embodiment of the present invention, a steering shaft for an automotive steering system has a circular groove at the bottom end of the bolt, a bolt rod is installed inside the circular groove, and a nut is installed after the bolt rod is screwed into the bolt hole.

[0007] As a preferred embodiment of the present invention, a steering shaft for an automotive steering system is provided, wherein a retaining ring is installed on the upper outer end of the bolt rod, and an annular pressure plate, a spring, and an annular rubber sheet are fitted onto the circumferential surface of the bolt rod.

[0008] As a preferred embodiment of the present invention, a steering shaft for an automotive steering system has an extrusion block installed at the upper edge of the annular rubber sheet.

[0009] As a preferred embodiment of the present invention, the heat-absorbing component includes a heat-absorbing shaft, and a plurality of sets of heat-conducting strips are installed on the outer surface of the heat-absorbing shaft. Each set of the heat-conducting strips consists of four strips, and a heat-conducting ring is connected to the side of the outer surface of each set of heat-conducting strips away from the heat-absorbing shaft.

[0010] As a preferred embodiment of the present invention, a steering shaft for an automotive steering system is provided, wherein one end of the steering shaft is fitted with a first gear and the other end of the steering shaft is fitted with a second gear.

[0011] Compared with the prior art, the beneficial effects of this utility model are: the setting of the steering shaft for the automobile steering system has a reasonable structural design;

[0012] The protective bushing fitted to the steering shaft body in this patent has a heat-absorbing component inside, including a heat-absorbing shaft, a heat-conducting strip, and a heat-conducting ring. It can quickly absorb the heat generated by the operation of the steering shaft and conduct and diffuse the heat through the heat-conducting strip and the heat-conducting ring, effectively reducing the temperature of the steering shaft, avoiding the degradation of material properties and accelerated wear caused by high temperature, and greatly improving the service life and reliability of the steering shaft.

[0013] The lubrication cylinders assembled at both ends of the steering shaft have rotating cavities and balls on the inner walls of cylinder a and cylinder b. The balls roll in the rotating cavities, which can reduce the friction when the steering shaft rotates. At the same time, the rolling of the balls can also drive the lubricating oil to circulate in the rotating cavities, achieving continuous and efficient lubrication, reducing rotational resistance, making the driver's operation easier, reducing component wear, and reducing maintenance costs.

[0014] The lubrication cylinder's shafts a and b are connected via a connecting plate, threaded holes, bolts, and other structures. The bolts' unique design, including features such as a circular groove, bolt shank, retaining ring, annular pressure plate, spring, and annular rubber sheet, facilitates easier installation and disassembly. During installation, the spring's elasticity ensures the annular rubber sheet fits tightly against the connection, enhancing sealing and preventing lubricant leakage. Simultaneously, the fit between the bolt shank and threaded hole, along with the retaining ring and other structural elements, guarantees connection stability, preventing loosening and ensuring the normal operation of the steering system. Attached Figure Description

[0015] Figure 1 This is a front-view three-dimensional structural schematic diagram of the present invention;

[0016] Figure 2 This is a schematic diagram of the protective bushing of this utility model;

[0017] Figure 3 This is a schematic diagram of the lubrication cylinder of this utility model;

[0018] Figure 4 This is a schematic diagram of the bolt of this utility model.

[0019] In the diagram: 1. Steering shaft; 2. First gear; 3. Protective bushing; 31. Spline groove; 32. Sleeve body; 33. Heat-absorbing component; 331. Heat-absorbing shaft; 332. Heat-conducting ring; 333. Heat-conducting strip; 4. Second gear; 5. Lubrication cylinder; 51. Shaft cylinder a; 52. Shaft cylinder b; 6. Ball bearing; 7. Rotating cavity; 8. Connecting plate; 9. Screw hole; 10. Bolt; 101. Circular groove; 102. Annular rubber sheet; 103. Bolt rod; 104. Extrusion block; 105. Annular pressure plate; 106. Retaining ring; 107. Spring. Detailed Implementation

[0020] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0021] Please see Figure 1-4 This utility model provides a technical solution:

[0022] In this technical solution, a steering shaft for an automotive steering system includes a steering shaft 1. A protective bushing 3 is fitted on the shaft body of the steering shaft 1, and lubrication cylinders 5 are fitted on both ends of the steering shaft 1. The protective bushing 3 includes a heat-absorbing element 33, and a sleeve body 32 is fitted onto the outer surface of the heat-absorbing element 33. The outer surface of the sleeve body 32 has several equally spaced spline grooves 31, and the sleeve body 32 is fitted onto the outside of the steering shaft 1. The lubrication cylinder 5 includes a shaft cylinder a51 and a shaft cylinder b52 arranged opposite to each other. Connecting plates 8 are installed on the outer walls of both sides of the shaft cylinder a51 and the shaft cylinder b52. The side walls of the two connecting plates 8 on the left and right sides are provided with screw holes 9, and bolts 10 are screwed into the screw holes 9.

[0023] The steering shaft 1 is the core component of the entire steering system that transmits steering force. It connects with the steering wheel, steering gear, and other components to transmit the force exerted by the driver turning the steering wheel to the steering mechanism, thus enabling vehicle steering. The protective bushing 3 is mounted on the steering shaft 1 and primarily protects the shaft, reducing wear from external factors and providing some heat dissipation. The lubrication cylinders 5 are installed at both ends of the steering shaft 1 to lubricate the connections between the steering shaft 1 and other components, reducing frictional resistance during rotation.

[0024] The length of the steering shaft 1 is usually determined according to the layout of the car's steering system, with a common length range of 300-600mm and a diameter of 20-40mm. The length of the protective bushing 3 is about 1 / 3 to 1 / 2 of the length of the steering shaft 1, and its inner diameter is slightly larger than the outer diameter of the steering shaft 1 by 0.1-0.3mm to ensure a tight fit. The length of the lubrication cylinder 5 is about 50-100mm, and its inner diameter matches the end diameter of the steering shaft 1, with the error controlled within ±0.05mm.

[0025] The length of the steering shaft 1 is usually determined according to the layout of the car's steering system, with a common length range of 300-600mm and a diameter of 20-40mm. The length of the protective bushing 3 is about 1 / 3 to 1 / 2 of the length of the steering shaft 1, and its inner diameter is slightly larger than the outer diameter of the steering shaft 1 by 0.1-0.3mm to ensure a tight fit. The length of the lubrication cylinder 5 is about 50-100mm, and its inner diameter matches the end diameter of the steering shaft 1, with the error controlled within ±0.05mm.

[0026] The heat absorber 33 is mainly responsible for absorbing the heat generated during the operation of the steering shaft 1 to prevent the shaft temperature from being too high and affecting performance; the sleeve 32 serves as the outer shell of the heat absorber 33, which protects it. At the same time, the design of the spline groove 31 facilitates connection with other splined components to achieve torque transmission.

[0027] The wall thickness of the sleeve 32 is generally 2-3mm to ensure strength and heat dissipation; the number of spline grooves 31 is usually designed according to actual needs, commonly 6-12, with a groove width of 5-8mm and a groove depth of 3-5mm; the outer diameter of the heat-absorbing element 33 is 0.2-0.4mm smaller than the inner diameter of the sleeve 32 to ensure a tight fit.

[0028] The material of the heat absorber 33 can be a metal material with good thermal conductivity, such as a copper alloy.

[0029] The material of the heat absorber 33 can be a metal material with good thermal conductivity, such as aluminum or copper alloy; the tooth profile parameters of the spline groove 31 are not mentioned. Generally, a rectangular spline or an involute spline is used, and its module, pressure angle and other parameters need to be specified.

[0030] The wall thickness of shaft cylinders a51 and b52 is approximately 1.5-2.5mm to ensure structural strength and oil storage space; the thickness of connecting plate 8 is 3-5mm, and its size is designed according to the size of the shaft cylinder to ensure a stable connection; the diameter of screw hole 9 is generally 0.5-1mm larger than the nominal diameter of bolt 10 to ensure that the bolt can be screwed in smoothly.

[0031] The inner wall surface treatment of shaft cylinders a51 and b52 can be carried out by hard chrome plating or polishing in order to better store lubricating oil and reduce friction.

[0032] In some technical solutions, rotating cavities 7 are evenly spaced along the axis of the inner walls of shaft cylinders a51 and b52, and ball bearings 6 are installed inside the rotating cavities 7.

[0033] The design of the rotating cavity 7 and the ball 6 can convert the sliding friction between the steering shaft 1 and the inner wall of the lubrication cylinder 5 into rolling friction, which greatly reduces the frictional resistance. At the same time, the rolling of the ball 6 in the rotating cavity 7 can drive the flow of lubricating oil and achieve better lubrication effect.

[0034] The diameter of the rotating cavity 7 is generally 0.1-0.2mm larger than that of the ball 6 to ensure that the ball 6 can roll freely; the number of rotating cavities 7 is usually 6-12, evenly distributed on the circumference of the inner wall of the shaft cylinder; the diameter of the ball 6 is commonly 3-6mm, made of high-precision bearing steel, with a hardness of HRC60-65;

[0035] The depth of the rotating cavity 7 is generally 1 / 3 to 1 / 2 of the diameter of the ball 6 to ensure stable rolling of the ball 6; the fitting accuracy between the ball 6 and the rotating cavity 7 can be P5 or P4 grade.

[0036] In some technical solutions, a circular groove 101 is provided at the bottom end of the bolt 10, and a bolt rod 103 is installed inside the circular groove 101. After the bolt rod 103 is screwed into the bolt hole 9, a nut is installed.

[0037] The circular groove 101 is used to accommodate the bolt shank 103. This design makes the bolt 10 structure more compact, while the bolt shank 103 cooperates with the nut to enhance the stability of the connection.

[0038] The diameter of the circular groove 101 is 0.5-1mm larger than the diameter of the bolt rod 103, and the depth is designed according to the length of the bolt rod 103 to ensure that the bolt rod 103 can be fully screwed in. The length of the bolt rod 103 is generally determined according to the thickness of the connecting plate 8 and the depth of the screw hole 9 to ensure that there is sufficient thread engagement length after screwing in. Usually, the engagement length is not less than 1.2 times the nominal diameter of the bolt rod 103.

[0039] In some technical solutions, an extrusion block 104 is installed at the upper edge of the annular rubber sheet 102.

[0040] The annular rubber sheet 102 has good elasticity and sealing properties. During the tightening process of the bolt 10, the extrusion block 104 can squeeze the annular rubber sheet 102 to make it fit tightly against the connection part, prevent lubricating oil leakage, and enhance the sealing and stability of the connection.

[0041] The thickness of the annular rubber sheet 102 is 1-2mm, the inner diameter is adapted to the diameter of the bolt rod 103, and the outer diameter is designed according to the size of the circular groove 101 to ensure that it can completely cover the connection gap; the height of the extrusion block 104 is 2-3mm, the width is 3-5mm, and the material can be plastic or metal with high hardness.

[0042] In some technical solutions, the heat-absorbing component 33 includes a heat-absorbing shaft 331, and a number of sets of heat-conducting strips 333 are installed on the outer surface of the heat-absorbing shaft 331. Each set of heat-conducting strips 333 has four strips, and a heat-conducting ring 332 is connected to the side of the outer surface of each set of heat-conducting strips 333 away from the heat-absorbing shaft 331.

[0043] The heat-absorbing shaft 331 directly contacts the steering shaft 1 to absorb heat. The heat-conducting strip 333 and the heat-conducting ring 332 form a heat dissipation network, which quickly conducts and diffuses heat to the outside, improving heat dissipation efficiency.

[0044] The diameter of the heat-absorbing shaft 331 is 0.5-1mm smaller than the outer diameter of the steering shaft 1, and its length is adapted to the inner diameter of the protective bushing 3; the width of the heat-conducting strip 333 is 3-5mm, the thickness is 1-2mm, and the length is designed according to the size of the protective bushing 3 to ensure effective heat conduction; the thickness of the heat-conducting ring 332 is 2-3mm, the inner diameter is 1-2mm larger than the outer diameter of the heat-absorbing shaft 331, and the outer diameter is adapted to the inner diameter of the sleeve 32;

[0045] The thermal conductivity of the heat-conducting strip 333 and the heat-conducting ring 332 is selected from materials with excellent thermal conductivity; the connection between the heat-absorbing shaft 331, the heat-conducting strip 333 and the heat-conducting ring 332 is achieved by brazing.

[0046] In some technical solutions, a first gear 2 is mounted on one end of the steering shaft 1, and a second gear 4 is mounted on the other end of the steering shaft 1.

[0047] The first gear 2 and the second gear 4 are used to mesh with other gear components in the steering system to realize the transmission of steering force and the transformation of steering angle, so as to ensure the accuracy and stability of vehicle steering;

[0048] The module of the first gear 2 and the second gear 4 is determined according to the transmission requirements of the steering system, and is usually 2-4mm; the number of teeth is calculated according to the transmission ratio, and is generally between 15-30 teeth; the tooth width of the gear is 10-20mm to ensure sufficient load-bearing capacity; the gear material is generally 20CrMnTi carburizing steel, and after carburizing and quenching treatment, the tooth surface hardness reaches HRC58-62.

[0049] The gear precision grade is 7-8 for automotive steering system gears; the first gear 2 and the second gear 4 are assembled with the steering shaft 1 using key connection or interference fit, and are axially positioned.

[0050] Working process and principle:

[0051] Overall power transmission basics: When the driver turns the steering wheel, the torque is first transmitted to the steering shaft 1. As the core transmission component, the steering shaft 1, with its high-strength structure (usually made of alloy steel such as 40Cr), converts the rotation of the steering wheel into axial torque. Through the first gear 2 and the second gear 4 mounted at both ends, it meshes with other gear components of the steering system, further transmitting the torque to the steering gear, driving the steering mechanism to achieve the car's steering action.

[0052] Heat dissipation and protection of the protective bushing: During the operation of the steering shaft 1, the shaft body generates a large amount of heat due to friction. The heat-absorbing shaft 331 in the protective bushing 3 is in direct contact with the steering shaft 1 and rapidly absorbs heat using its high thermal conductivity (e.g., using copper or aluminum alloy with high thermal conductivity). The heat is conducted to the heat-conducting ring 332 through the heat-conducting strips 333 evenly distributed on the outer surface of the heat-absorbing shaft 331, forming a three-dimensional heat dissipation network. The heat-conducting ring 332 then dissipates the heat into the surrounding air, thereby reducing the temperature of the steering shaft 1 and preventing material performance degradation and accelerated wear due to overheating. At the same time, the spline groove 31 on the outer surface of the bushing 32 can connect with other splined components, not only to assist in torque transmission but also to provide circumferential positioning for the protective bushing 3, enhancing the overall structural stability.

[0053] Lubrication and friction reduction in the lubrication cylinders: The rolling balls 6 installed in the rotating cavities 7 on the inner walls of the lubrication cylinders 5 at both ends of the steering shaft 1, specifically in the cylinders a51 and b52, play a crucial role. When the steering shaft 1 rotates, the rolling balls 6 roll within the rotating cavities 7, converting the sliding friction between the steering shaft 1 and the inner wall of the lubrication cylinder into rolling friction. The coefficient of rolling friction is much lower than the coefficient of sliding friction, which significantly reduces rotational resistance. Simultaneously, the rolling of the rolling balls 6 agitates the lubricating oil stored in the lubrication cylinders, causing it to circulate between the rotating cavities 7 and the steering shaft 1, continuously providing lubrication to the rotating parts, reducing wear, and extending the service life of the steering shaft 1 and related components.

[0054] The bolted connection structure ensures stability and sealing: The lubrication cylinder 5 is connected to shaft cylinders a51 and b52 via connecting plate 8, screw holes 9, and bolts 10. During installation, the bolt shank 103 is screwed into screw hole 9 and the nut is tightened. The structural design within the circular groove 101 at the bottom of bolt 10, in conjunction with the fixing ring 106, annular pressure plate 105, spring 107, and annular rubber sheet 102, achieves a stable connection and seal. During the tightening of bolt 10, the elastic force of spring 107 pushes the annular pressure plate 105, thereby squeezing the annular rubber sheet 102, making it tightly fit the gap between connecting plates 8. The presence of the compression block 104 further enhances the compression effect on the annular rubber sheet 102, effectively preventing lubricating oil leakage and ensuring a stable lubrication environment inside the lubrication cylinder 5.

[0055] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0056] Although the present invention has been described above with reference to embodiments, various modifications can be made and components can be replaced with equivalents without departing from the scope of the present invention. In particular, as long as there is no structural conflict, the features in the embodiments disclosed in this invention can be combined with each other in any way. The lack of an exhaustive description of these combinations in this specification is merely for the sake of brevity and resource conservation. Therefore, the present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A steering shaft for an automobile steering system, comprising a steering shaft (1), characterized in that, The steering shaft (1) is fitted with a protective bushing (3), and both ends of the steering shaft (1) are fitted with lubrication cylinders (5). The protective bushing (3) includes a heat-absorbing element (33), and a sleeve body (32) is sleeved on the outer surface of the heat-absorbing element (33). The outer surface of the sleeve body (32) has several equally spaced spline grooves (31), and the sleeve body (32) is sleeved on the outside of the steering shaft (1). The lubrication cylinder (5) includes a shaft cylinder a (51) and a shaft cylinder b (52) arranged opposite to each other, and connecting plates (8) are installed on both outer walls of the shaft cylinder a (51) and the shaft cylinder b (52); The two connecting plates (8) on the left and right sides are provided with screw holes (9) on their side walls, and bolts (10) are screwed into the screw holes (9).

2. The steering shaft for an automobile steering system according to claim 1, characterized in that, The inner walls of the shaft cylinders a (51) and b (52) are provided with rotating cavities (7) evenly spaced along their axes, and ball bearings (6) are installed inside the rotating cavities (7).

3. A steering shaft for an automobile steering system according to claim 1, characterized in that, The bottom end of the bolt (10) is provided with a circular groove (101), and a bolt rod (103) is installed inside the circular groove (101). After the bolt rod (103) is screwed into the bolt hole (9), a nut is installed.

4. A steering shaft for an automobile steering system according to claim 3, characterized in that, A retaining ring (106) is installed on the upper outer end of the bolt rod (103), and an annular pressure plate (105), a spring (107) and an annular rubber sheet (102) are fitted on the circumferential surface of the bolt rod (103).

5. A steering shaft for an automobile steering system according to claim 4, characterized in that, An extrusion block (104) is installed at the upper edge of the annular rubber sheet (102).

6. A steering shaft for an automobile steering system according to claim 1, characterized in that, The heat-absorbing component (33) includes a heat-absorbing shaft (331), and a number of sets of heat-conducting strips (333) are installed on the outer surface of the heat-absorbing shaft (331). Each set of heat-conducting strips (333) has four strips, and a heat-conducting ring (332) is connected to the side of the outer surface of each set of heat-conducting strips (333) away from the heat-absorbing shaft (331).

7. A steering shaft for an automobile steering system according to claim 1, characterized in that, One end of the steering shaft (1) is equipped with a first gear (2), and the other end of the steering shaft (1) is equipped with a second gear (4).

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