Electric torsion bar assembling structure for electric power steering device

Abstract

The utility model discloses an electric torsion bar assembly structure for an electric power steering device, which comprises an assembly shell, an upper power-assisted shaft and a lower power-assisted shaft which are coaxially arranged up and down and directly face each other are rotatably mounted on the assembly shell, a torsion bar is connected between the upper power-assisted shaft and the lower power-assisted shaft, and the torsion bar is constructed into a hexagonal prism structure. An upper hollow part extending from bottom to top is arranged at the lower end of the upper boosting shaft, and a lower hollow part extending from top to bottom is arranged at the upper end of the lower boosting shaft; the upper hollow part and the lower hollow part are hexagonal holes matched with the torsion bar, and the upper end and the lower end of the torsion bar are inserted into the upper hollow part and the lower hollow part respectively. The assembly structure has the advantages that the torsion bar is arranged to be of the hexagonal prism structure, the upper hollow portion and the lower hollow portion are arranged to be the hexagonal holes matched with the torsion bar, the torsion bar can be rapidly positioned and installed, and the assembly structure can prevent the torsion bar from rotating relative to the upper assistance shaft and the lower assistance shaft.

Description

Technical Field

[0001] This utility model relates to the technical field of automotive power steering devices, specifically to an assembly structure for an electric torsion bar in an electric power steering device. Background Technology

[0002] Power steering is an essential component of a car's steering system. It reduces the effort required for the driver to turn the steering wheel, making driving easier and safer. Specifically, power steering uses external power (such as hydraulic or electric) to assist the driver in turning the steering wheel, thereby reducing physical exertion.

[0003] In terms of structural composition, the power steering system mainly includes an upper power steering shaft and a lower power steering shaft, which are connected by a torsion bar. The upper power steering shaft is connected to the car's steering wheel, and the lower power steering shaft is connected to the lateral tie rod between the two front wheels of the car. When the steering wheel drives the upper power steering shaft to rotate, it can transmit the signal through the torsion bar, thereby driving the lower power steering shaft to rotate. The power steering system also includes a power steering motor, which mainly relies on the torsional deformation of the torsion bar to obtain a signal, thereby driving the lower power steering shaft to rotate.

[0004] In the existing technology, the torsion bar is a cylindrical structure. Both the upper and lower power steering shafts have circular mounting holes that match the torsion bar. After the two ends of the torsion bar are inserted into the circular mounting holes, in order to prevent slippage between the bar and the hole and to ensure that the torque can be effectively transmitted between the upper and lower power steering shafts, a radial locking pin needs to be inserted between the torsion bar and the circular mounting hole. Installing the radial locking pin in the power steering assembly is a cumbersome operation that seriously affects the assembly efficiency of the entire power steering device. Utility Model Content

[0005] In view of this, the present invention provides an assembly structure for an electric torsion bar in an electric power steering device, which enables quick positioning and installation of the torsion bar.

[0006] To achieve the above objectives, the technical solution of this utility model is as follows:

[0007] An electric torsion bar assembly structure for an electric power steering device includes an assembly housing. An upper power steering shaft and a lower power steering shaft are rotatably mounted on the assembly housing, coaxially arranged opposite each other. A torsion bar connects the upper and lower power steering shafts. The torsion bar is characterized by being constructed as a hexagonal prism structure. The lower end of the upper power steering shaft has an upper hollow portion extending upwards, and the upper end of the lower power steering shaft has a lower hollow portion extending downwards. Both the upper and lower hollow portions are hexagonal holes adapted to the torsion bar, and the upper and lower ends of the torsion bar are respectively inserted into the upper and lower hollow portions.

[0008] By adopting the above structure, and by setting the torsion bar as a hexagonal prism and the upper and lower hollow parts as hexagonal structures adapted to the torsion bar, rapid assembly can be achieved by inserting both ends of the torsion bar into the hexagonal holes. This improves the assembly efficiency of the power steering device. Furthermore, this assembly structure prevents the torsion bar from rotating relative to the upper and lower power steering shafts, thus ensuring effective torque transmission in the power steering system. Secondly, the hexagonal torsion bar also has the technical advantages of simple structure, low cost, and ease of manufacturing.

[0009] Preferably, a first bearing is fitted onto the lower power steering shaft, and the outer ring of the first bearing is fixedly fitted onto the assembly housing. With this structure, when the steering wheel drives the upper power steering shaft to rotate, the torsion bar can drive the lower power steering shaft to rotate relative to the assembly housing, ultimately transmitting force to the lateral tie rod to achieve vehicle steering.

[0010] Preferably, the lower shaft is fitted with a worm gear, and the assembly housing has a worm gear mounting chamber, the radial dimension of which is larger than the radial dimension of the worm gear. This structure ensures that when the lower shaft rotates, it drives the worm gear to rotate as well.

[0011] Preferably, the assembly housing has a through hole running horizontally through it, and a worm gear capable of meshing and driving the worm wheel is inserted into the through hole. The distal end of the worm gear is used to connect to the power steering motor. This structure provides assistance to the rotation of the power steering shaft, thereby reducing the physical burden on the driver when turning the steering wheel.

[0012] Preferably, the worm gear mounting chamber has a downwardly extending annular portion in the middle, and the outer ring of the first bearing is fixedly supported on the inner wall of the annular extension. This structure ensures stable installation of the first bearing.

[0013] Preferably, the lower end of the lower shaft has an external thread, and a support ring is threaded onto the external thread, with the bottom of the first bearing supported on the top of the support ring. This structure prevents the first bearing from falling off.

[0014] Preferably, a second bearing is fitted at the lower end of the upper assist shaft, with the outer wall of the second bearing tightly against the inner wall of the lower assist shaft. This structure allows for a rotatable connection between the upper and lower assist shafts, and a torsion bar connects them. When the upper assist shaft rotates, the torsion bar is first subjected to torsional force, which is then transmitted to the lower assist shaft, causing it to rotate.

[0015] Compared with the prior art, the beneficial effects of this utility model are:

[0016] The electric torsion bar assembly structure for electric power steering devices provided by this utility model achieves rapid assembly by designing the torsion bar as a hexagonal prism and shaping the upper and lower hollow sections into hexagonal holes adapted to the torsion bar. The two ends of the torsion bar are inserted into these hexagonal holes, thus improving the assembly efficiency of the power steering device. Furthermore, this assembly structure prevents the torsion bar from rotating relative to the upper and lower power steering shafts, ensuring effective torque transmission within the power steering system. Additionally, the hexagonal torsion bar structure offers advantages such as simple structure, low cost, and ease of manufacturing. Attached Figure Description

[0017] Figure 1 A three-dimensional structural diagram of an electric power steering system;

[0018] Figure 2 for Figure 1 Top view;

[0019] Figure 3 For along Figure 2 Sectional view of AA;

[0020] Figure 4 This is a schematic diagram of the structure of torsion bar 3;

[0021] Figure 5 A schematic diagram of the structure of the lower shaft 2;

[0022] Figure 6 A partial sectional view showing the assembly relationship between the torsion bar 3 and the upper hollow part 1a. Detailed Implementation

[0023] The present invention will be further described below with reference to the embodiments and accompanying drawings.

[0024] like Figure 1 , Figure 3 , Figure 4 and Figure 6 As shown, an electric torsion bar assembly structure for an electric power steering device includes an assembly housing 4. An upper power steering shaft 1 and a lower power steering shaft 2, arranged vertically opposite each other, are rotatably mounted on the assembly housing 4. A torsion bar 3 is connected between the upper power steering shaft 1 and the lower power steering shaft 2. The torsion bar 3 is constructed as a hexagonal prism structure. The lower end of the upper power steering shaft 1 has an upper hollow portion 1a extending from bottom to top, and the upper end of the lower power steering shaft 2 has a lower hollow portion 2a extending from top to bottom. Both the upper hollow portion 1a and the lower hollow portion 2a are hexagonal holes adapted to the torsion bar 3. The upper and lower ends of the torsion bar 3 are respectively inserted into the upper hollow portion 1a and the lower hollow portion.

[0025] This design, by transforming the torsion bar 3 from a traditional cylindrical structure into a hexagonal prism structure, and by setting the upper hollow portion 1a and the lower hollow portion 2a into hexagonal holes adapted to the torsion bar 3, allows for rapid positioning and assembly by inserting both ends of the torsion bar 3 into the hexagonal holes. This improves the assembly efficiency of the power steering device. Furthermore, this assembly structure prevents the torsion bar 3 from rotating relative to the upper and lower power steering shafts 1 and 2, thus ensuring effective torque transmission in the power steering system. Secondly, the hexagonal structure of the torsion bar 3 also offers advantages such as simple structure, low cost, and ease of manufacturing.

[0026] like Figure 3 and Figure 5 As shown, a worm gear 6 is fixedly mounted on the lower shaft 2, and a worm gear mounting chamber 4a is formed on the assembly housing 4. The radial dimension of the worm gear mounting chamber 4a is larger than the radial dimension of the worm gear 6. With this design, when the lower shaft 2 rotates relative to the assembly housing 4, it can drive the worm gear 6 to rotate together.

[0027] like Figure 1 and Figure 3 As shown, the assembly housing 4 also has a through hole 4b formed in the horizontal direction. A worm (not shown in the figure) that can mesh with the worm wheel 6 is inserted in the through hole 4b. The far end of the worm is used to connect to the power assist motor (not shown in the figure). The power assist motor drives the worm to rotate the worm wheel 6, which can reduce the physical burden on the driver when turning the steering wheel and make it easier for the driver to control the driving direction of the car.

[0028] like Figure 5 As shown, a first bearing 5 is sleeved on the lower shaft 2, and the outer ring of the first bearing 5 is fixedly sleeved on the assembly housing 4.

[0029] Specifically, such as Figure 3 As shown, a downwardly extending annular extension 4c is formed in the middle of the worm gear mounting chamber 4a. The outer ring of the first bearing 5 is fixedly supported on the inner wall of the annular extension 4c. In this embodiment, two first bearings 5 ​​are fixedly arranged inside the annular extension 4c. This design enables the lower shaft 2 to slide stably relative to the annular extension 4c.

[0030] like Figure 3 and Figure 5 As shown, an external thread 2b is formed on the lower outer surface of the assisted shaft 2. A threaded support ring 7 is installed on the external thread 2b. A flange 7a extending outward in a circumferential direction is formed on the top of the support ring 7. The bottom of the first bearing 5 located at the lower end is supported on the top of the support ring 7, so as to ensure that the first bearing 5 will not fall off the bottom of the assembly housing 4.

[0031] like Figure 3As shown, a second bearing 8 is fitted at the lower end of the upper power steering shaft 1. The outer wall of the second bearing 8 is in close contact with the inner wall of the lower power steering shaft 2. This design allows the upper power steering shaft 1 and the lower power steering shaft 2 to be rotatably connected. Since a torsion bar 3 connects the upper power steering shaft 1 and the lower power steering shaft 2, when the steering wheel drives the upper power steering shaft 1 to rotate, the torsion bar 3 will inevitably be subjected to the torsional force of the upper power steering shaft 1 first, and then the torsional force it receives will be transmitted to the lower power steering shaft 2 through the torsion bar 3, so that the lower power steering shaft 2 can rotate.

[0032] In this embodiment, a detection element (not shown in the figure) is also provided inside the assembly housing 4. The detection element is used to detect the deformation of the torsion bar 3. The detection element is also electrically connected to the assist motor. When the detection element detects that the torsion bar 3 is deformed due to the rotation of the upper assist shaft 1, it can promptly provide feedback to the assist motor, causing the assist motor to operate to assist the rotation of the lower assist shaft 2. In addition, the detection element can also provide feedback signals to the assist motor by detecting the relative angle change between the upper assist shaft 1 and the lower assist shaft 2.

[0033] Finally, it should be noted that the above description is merely a preferred embodiment of the present utility model. Those skilled in the art, under the guidance of the present utility model, can make various similar representations without departing from the spirit and claims of the present utility model, and such modifications all fall within the protection scope of the present utility model.

Claims

1. An electric torsion bar assembly structure for an electric power steering device, comprising an assembly housing (4), wherein an upper power steering shaft (1) and a lower power steering shaft (2) are rotatably mounted on the assembly housing (4) and arranged coaxially opposite each other, and a torsion bar (3) is connected between the upper power steering shaft (1) and the lower power steering shaft (2), characterized in that: The torsion bar (3) is constructed as a hexagonal prism structure, the upper shaft (1) has an upper hollow portion (1a) extending from bottom to top at its lower end, and the lower shaft (2) has a lower hollow portion (2a) extending from top to bottom at its upper end. The upper hollow part (1a) and the lower hollow part (2a) are both hexagonal holes adapted to the torsion bar (3), and the upper and lower ends of the torsion bar (3) are respectively inserted into the upper hollow part (1a) and the lower hollow part (2a).

2. The electric torsion bar assembly structure for an electric power steering device according to claim 1, characterized in that: The lower shaft (2) is fitted with a first bearing (5), and the outer ring of the first bearing (5) is fixedly fitted on the assembly housing (4).

3. The electric torsion bar assembly structure for an electric power steering device according to claim 2, characterized in that: The lower shaft (2) is fixedly fitted with a worm gear (6), and the assembly housing (4) is provided with a worm gear mounting chamber (4a), the radial dimension of which is greater than the radial dimension of the worm gear (6).

4. The electric torque rod assembly structure for an electric power steering apparatus according to claim 3, characterized by: The assembly housing (4) has a through hole (4b) extending horizontally, and a worm gear capable of meshing and driving with the worm wheel (6) is inserted in the through hole (4b), the distal end of which is used to connect to the power assist motor.

5. The electric torque rod assembly structure for an electric power steering apparatus according to claim 3, characterized by: The worm gear mounting chamber (4a) has a downwardly extending annular extension (4c) in the middle, and the outer ring of the first bearing (5) is fixedly supported on the inner wall of the annular extension (4c).

6. The electric torsion bar assembly structure for an electric power steering device according to claim 5, characterized in that: The lower end of the lower shaft (2) is provided with an external thread (2b), and a support ring (7) is provided on the external thread (2b) and the bottom of the first bearing (5) is supported on the top of the support ring (7).

7. The electric torque rod assembly structure for an electric power steering apparatus according to claim 1, characterized by: The lower end of the upper assist shaft (1) is fitted with a second bearing (8), and the outer wall of the second bearing (8) is in close contact with the inner wall of the lower assist shaft (2).

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