Lead screw nut hard limiting structure for electrically-controlled tubular column

Abstract

The utility model relates to the technical field of steering systems, in particular to a lead screw nut hard limiting structure for an electrically-controlled tubular column. A lead screw nut hard limiting structure for an electrically-controlled tubular column comprises a lead screw and limiting blocks and is characterized in that the end of the lead screw is in shaft connection with a worm gear, the two ends of threads of the lead screw are connected with an upper limiting block and a lower limiting block respectively, the upper limiting block and the lower limiting block are in shaft connection with the upper end and the lower end of the lead screw respectively, and the worm gear is located below the lower limiting block; the lead screw, the worm gear, the upper limiting block and the lower limiting block are integrally formed in an injection molding mode. Compared with the prior art, according to the lead screw nut hard limiting structure for the electrically-controlled tubular column, an injection molding structure is adopted for flexible adjustment according to the stroke requirement of a customer and the structural design, so that the universality of the same lead screw is enhanced, assembly parts are reduced, the reliability is improved, the input of a preassembling production line is reduced, the beat is improved, and the product cost is reduced.

Description

Technical Field

[0001] This utility model relates to the field of steering system technology, specifically to a hard-limiting structure for a lead screw nut in an electronically controlled steering column. Background Technology

[0002] The electric adjusting column has a four-way adjustment function. The stroke adjustment principle is based on the motor driving the lead screw, which drives the lead screw nut and the adjusting part to move. The stroke is adjusted according to customer requirements and actual design structure, and hard limits are installed at the front and rear positions of the lead screw. Often, due to different customer structures and requirements, the adjustment stroke is different, the lead screw length needs to be adjusted, and the hard limit structure also needs to be adjusted. The product has poor versatility, and there are many models of lead screw limit sleeves, which can easily lead to material mixing.

[0003] Due to varying customer requirements for the four-way adjustment of the ESC and differences in product structure, the hard limit of the motor lead screw often varies, as does the lead screw length, resulting in poor product versatility, high mold costs, and high error prevention costs. The lead screw hard limit composed of the previous three parts also has a complex structure and poor reliability, high equipment investment and long production cycle during assembly, and there is a risk of detachment and abnormal noise during use. Summary of the Invention

[0004] To overcome the shortcomings of the prior art, this utility model provides a hard-limiting structure for the lead screw nut of an electrically adjustable column. The injection-molded structure is flexibly adjusted according to customer stroke requirements and structural design, which enhances the versatility of the same lead screw, reduces the number of assembly parts and improves reliability, reduces pre-assembly production line investment and increases cycle time, and reduces product cost.

[0005] To achieve the above objectives, a hard-limiting structure for a lead screw nut in an electrically adjustable tube column is designed, comprising a lead screw and a limiting block. The characteristic feature is that a worm gear is shaft-connected to the end of the lead screw, and an upper limiting block and a lower limiting block are respectively connected to the threaded ends of the lead screw. The upper and lower limiting blocks are shaft-connected to the upper and lower ends of the lead screw, respectively, with the worm gear located below the lower limiting block. The lead screw, worm gear, upper limiting block, and lower limiting block are integrally injection molded.

[0006] The upper limit block and lower limit block are cylindrical injection-molded limit block structures. The height of the lower limit block is greater than that of the upper limit block, and the diameters of the upper limit block and lower limit block are the same.

[0007] The worm gear mentioned is an injection-molded worm gear.

[0008] The aforementioned hard limiting structure is used in the lead screw and nut sub-assembly, on which the lead screw and nut are connected.

[0009] The aforementioned hard limiting structure is used in the motor sub-assembly. The end of the worm gear is connected to the drive shaft of the motor. A housing cover is provided on the outside of the worm gear and the motor. The reducer housing is connected below the housing cover.

[0010] The lower limit block is located at the top of the housing cover.

[0011] Compared with the prior art, this utility model provides a hard limit structure for the lead screw nut of an electrically adjustable column. The injection-molded structure can be flexibly adjusted according to customer stroke requirements and structural design, which enhances the versatility of the same lead screw, reduces the number of assembly parts and improves reliability, reduces the investment in pre-assembly production lines and increases cycle time, and reduces product costs. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the structure of this utility model.

[0013] Figure 2 This is a schematic diagram of the present invention installed on the lead screw and nut sub-assembly.

[0014] Figure 3 This is a schematic diagram of the present invention installed on a motor sub-assembly. Detailed Implementation

[0015] The present invention will be further described below with reference to the accompanying drawings.

[0016] like Figure 1 As shown, the end of the lead screw 1 is shafted to the worm gear 2, and the upper limit block 3 and the lower limit block 4 are respectively connected to the threaded ends of the lead screw 1. The upper limit block 3 and the lower limit block 4 are shafted to the upper and lower ends of the lead screw 1, respectively, and the worm gear 2 is located below the lower limit block 4. The lead screw 1, worm gear 2, upper limit block 3 and lower limit block 4 are injection molded as one piece.

[0017] The upper limit block 3 and the lower limit block 4 are cylindrical injection-molded limit block structures. The height of the lower limit block 4 is greater than the height of the upper limit block 3, and the diameters of the upper limit block 3 and the lower limit block 4 are the same.

[0018] Worm gear 2 is an injection-molded worm gear.

[0019] The hard limit structure is used in the lead screw and nut sub-assembly, and the lead screw nut 5 is connected to the lead screw 1.

[0020] like Figure 2 As shown, the lead screw and nut assembly consists of lead screw 1, worm gear 2, upper limit block 3, lower limit block 4, and lead screw nut 5. Lead screw 1 (including lead screw thread), worm gear 2 (injection molded worm gear), upper limit block 3, and lower limit block 4 (upper injection molded limit block and lower injection molded limit block) are one part. The lead screw nut 5 needs to be installed into the thread of lead screw 1 at the injection molding supplier to injection mold worm gear 2, upper limit block 3, and lower limit block 4 according to customer requirements. The working stroke of lead screw nut 5 is adjusted according to the length of upper limit block 3 and lower limit block 4 according to customer requirements.

[0021] like Figure 3As shown, the hard limiting structure of this utility model is used in a motor sub-assembly. The end of the worm gear 2 is connected to the drive shaft of the motor 6. A housing cover 7 is provided on the outside of the worm gear 2 and the motor 6. The reducer housing 7 is connected to the bottom of the housing cover 7. The lower limiting block 4 is located at the top of the housing cover 7.

[0022] Through the structural design of this utility model, the hard-limiting structure of the ESC column solves the problem of complex assembly process of the lead screw and nut sub-assembly, meets the customized requirements of different customers, reduces pre-assembly time, reduces equipment and tooling investment, improves production cycle time, and the injection-molded limit block provides reliable limiting, good compatibility, and low price. It ensures the limiting requirements of the ESC column during use.

[0023] The implementation steps of this utility model are as follows:

[0024] 1. Design process of the lead screw sub-assembly:

[0025] like Figure 1 As shown, the adjustment stroke and structure of the electric adjusting column vary depending on the needs of the OEM customers. Therefore, the lengths of the lead screw 1, upper limit block 3, and lower limit block 4 need to be redesigned according to the stroke of the lead screw nut. The diversity of these parts leads to complex production line equipment, poor tooling compatibility, poor error prevention measures, and often high costs, resulting in poor customer acceptance. Injection molding can be used to adjust the injection position and injection length of the limit blocks as needed.

[0026] 2. Assembly process of the lead screw and nut sub-assembly:

[0027] like Figure 2 As shown, when the worm gear 2 is produced by injection molding at the injection molding supplier, the screw nut 5 is installed at the same time, and the upper limit block 3 and lower limit block 4 are produced according to the customer's required stroke. This ensures the universality of the screw 1 and meets the customer's customized needs. Moreover, the supplier supplies the screw nut assembly, saving the time and tooling equipment investment for pre-installing the screw nut assembly, improving the factory's production efficiency and reducing costs.

[0028] 3. Motor sub-assembly assembly process:

[0029] like Figure 3 As shown, the lead screw and nut assembly uses upper limit block 3 and lower limit block 4 as hard limits to restrict the stroke of lead screw and nut 5. During use, since motor 6 has a soft limit, it basically does not touch the hard limit. When motor 6 or other mechanisms have problems, hard limits are needed to restrict the position of lead screw and nut 5 to ensure safety. The injection-molded limit structure has a buffer limit function and is sturdy. The mechanical limit has the advantages of reliable and noiseless operation.

[0030] As can be seen from the above implementation steps, this structure is simple, easy to understand, and easy to implement. Furthermore, this principle can be applied to other lead screw and nut structures requiring limit switches.

[0031] This novel structure has been successfully applied to the production of electrically adjustable tubular columns, and the results meet the requirements. Therefore, the purpose of the new design has been achieved.

Claims

1. A hard-limiting structure for a lead screw nut in an electrically adjustable tube column, comprising a lead screw and a limiting block, characterized in that: The end of the lead screw (1) is connected to the worm gear (2), and the upper limit block (3) and the lower limit block (4) are respectively connected to the two ends of the thread of the lead screw (1). The upper limit block (3) and the lower limit block (4) are respectively connected to the upper and lower ends of the lead screw (1), and the worm gear (2) is located below the lower limit block (4). The lead screw (1), worm gear (2), upper limit block (3) and lower limit block (4) are injection molded as one piece.

2. The hard-limiting structure for a lead screw nut in an electrically adjustable tube column according to claim 1, characterized in that: The upper limit block (3) and lower limit block (4) are cylindrical injection-molded limit block structures. The height of the lower limit block (4) is greater than the height of the upper limit block (3), and the diameters of the upper limit block (3) and lower limit block (4) are the same.

3. The hard-limiting structure for a lead screw nut in an electrically adjustable tube column according to claim 1, characterized in that: The worm gear (2) is an injection-molded worm gear.

4. The hard-limiting structure for a lead screw nut in an electrically adjustable tube column according to claim 1, characterized in that: The aforementioned hard limiting structure is used in the lead screw nut sub-assembly, and the lead screw nut (5) is connected to the lead screw (1).

5. The hard-limiting structure for a lead screw nut in an electrically adjustable tube column according to claim 1, characterized in that: The hard limit structure is used for the motor sub-assembly. The end of the worm gear (2) is connected to the drive shaft of the motor (6). A housing cover (7) is provided on the outside of the worm gear (2) and the motor (6). The reducer housing (8) is connected below the housing cover (7).

6. A hard-limiting structure for a lead screw nut in an electrically adjustable tube column according to claim 1 or 2, characterized in that: The lower limit block (4) is located at the top of the housing cover (7).

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