An EPB drive screw and an EPB caliper assembly
Patent Information
- Application Number
- CN202522006309.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-18
- Publication Date
- 2026-10-20
- Estimated Expiration
- 2035-09-18
AI Technical Summary
而螺杆具有依次连接的头部1、法兰部3以及杆部2，执行器总成通过端面轴承连接于头部1，因而为了满足法兰部3朝向头部1的端面装配端面轴承不干涩要求，需要对法兰部3以及头部1的连接处进行清根以形成清角结构，如图1所示，现有技术中所形成的清角结构过于简单，仅类似自法兰朝向头部的端面与头部相接处沿轴向向内凹陷的多个半球形槽部4，为了不干涉，切削余量大(每一半球形槽部4的深度达1.4mm，其远离螺杆中心轴线的一侧与螺杆中心轴线所成角度α也达45°)，且需要使用专用清角刀具进行一刀一刀的车削加工(这就涉及到换刀实施对法兰部3和头部1的加工，换刀易接刀损坏刀具)，加工效率低，且易发生振刀，导致加工精度低，而加工所得的螺杆强度也较差，其法兰根部易因应力集中导致头部断裂；此外，清角刀具的加工刚性不足，也会影响加工效率和精度
[0017]本实用新型所提供的EPB传动螺杆仍包括头部、杆部以及连接于头部和杆部之间的法兰部，头部和法兰部的连接处形成清角结构，清角结构包括由法兰部沿轴向朝向头部的端面向内凹陷的多个槽部，多个槽部首尾相连地围绕头部，不同的是，每一槽部沿EPB传动螺杆轴向的截面均呈半水滴形的扫掠体结构，在EPB传动螺杆的轴向上，槽部的深度不超过0.5mm，而槽部沿EPB传动螺杆的径向所具有的宽度仍和现有技术中保持一致，从而使得法兰部根部的切削余量少，螺杆整体强度更高，应力集中减少，由此有效减小了EPB传动螺杆在后续的正常使用过程中因法兰部根部应力集中而导致头部发生断裂的风险，更利于延长法兰部厚度更小的EPB传动螺杆的使用寿命；此外，由于每一槽部沿EPB传动螺杆轴向的截面均呈半水滴形的扫掠体结构，因此也可直接结合标准刀具及CNC加工程序将其直接与法兰部、头部通过连续性走刀完成加工，可有效缩短加工时长，节约生产成本。
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Figure CN224871747U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of brake technology, and in particular relates to an EPB transmission screw and an EPB caliper assembly. Background Technology
[0002] With the rapid development of the automotive industry and increasingly stringent market demands for safety performance, the Electronic Parking Brake (EPB), as a new generation of braking system, has gradually become the mainstream trend in the automotive industry. The EPB caliper assembly mainly consists of the caliper body, the EPB screw and sleeve, and the actuator assembly. The EPB screw and sleeve, as a crucial component of the caliper assembly, comprises a screw and a sleeve, typically made of high-strength alloy steel. When current flows, the actuator assembly drives the screw and sleeve to move, causing the caliper body to clamp or release the brake disc. The screw has a head 1, a flange 3, and a rod 2 connected in sequence. The actuator assembly is connected to the head 1 via an end-face bearing. Therefore, to ensure a smooth fit of the end-face bearing on the flange 3 facing the head 1, the connection between the flange 3 and the head 1 needs to be cleaned to form a clean angle structure. Figure 1 As shown, the existing corner clearing structure is too simple, merely resembling multiple hemispherical grooves 4 recessed axially inward at the junction of the flange end face and the head. To avoid interference, the cutting allowance is large (each hemispherical groove 4 has a depth of 1.4 mm, and the angle α between its side away from the screw's central axis and the screw's central axis is also 45°). Furthermore, it requires the use of a special corner clearing tool for one-cut-one-turn turning (which involves changing tools to process the flange 3 and the head 1, and tool changes can easily damage the tool). This results in low processing efficiency and a tendency for tool vibration, leading to low processing accuracy. The resulting screw also has poor strength, and the flange root is prone to head breakage due to stress concentration. In addition, the insufficient processing rigidity of the corner clearing tool also affects processing efficiency and accuracy. Utility Model Content
[0003] In view of the problems existing in the prior art, the main purpose of this utility model is to provide an EPB drive screw and a connecting structure. The provided EPB drive screw has a clever corner clearing structure design, which can be combined with standard tools and CNC machining programs for rapid prototyping. The cutting allowance is small, which can effectively improve the product strength and reduce the risk of head breakage due to stress concentration at the flange root.
[0004] The objective of this utility model is achieved through the following technical solution:
[0005] This utility model provides an EPB drive screw, which includes a head, a rod, and a flange connecting the head and the rod. The connection between the head and the flange forms a clear angle structure.
[0006] The clearing structure includes a plurality of grooves recessed inward from the end face of the flange portion toward the head along the axial direction, the plurality of grooves being connected end to end around the head; in the axial direction of the EPB drive screw, the cross-section of each groove portion is a semi-teardrop-shaped swept body structure; in the axial direction of the EPB drive screw, the depth of the groove portion does not exceed 0.5mm.
[0007] As a further description of the above technical solution, in the radial direction of the EPB drive screw, the end of the sweeping body structure away from the head is pointed at the end adjacent to the head.
[0008] As a further description of the above technical solution, the thickness of the flange portion in the axial direction of the EPB drive screw is no more than 6mm.
[0009] As a further description of the above technical solution, the connection between the head and the flange adopts a rounded transition, and the clear corner structure is closer to the rod than the rounded corner.
[0010] As a further description of the above technical solution, the corner clearing structure and the rounded corner are smoothly connected.
[0011] As a further description of the above technical solution, the depth of the fillet in the radial direction of the EPB drive screw does not exceed 0.2 mm.
[0012] As a further description of the above technical solution, in the axial direction of the EPB drive screw, the distance between the end of the fillet away from the flange and the end face of the flange facing the head does not exceed 0.5mm.
[0013] As a further description of the above technical solution, the outer wall of the rod is also formed with threads.
[0014] As a further description of the above technical solution, the rod, head, corner clearing structure and flange are integrally formed by CNC machining.
[0015] This utility model also provides an EPB caliper assembly, including the EPB drive screw as described above.
[0016] Based on the above technical solutions, the outstanding effects of this utility model are as follows:
[0017] The EPB drive screw provided by this utility model still includes a head, a rod, and a flange connecting the head and the rod. The connection between the head and the flange forms a clear-angle structure. This clear-angle structure includes multiple grooves recessed inward from the flange along the axial direction towards the head end. These grooves are connected end-to-end around the head. The difference is that the cross-section of each groove along the axial direction of the EPB drive screw is a semi-teardrop-shaped swept-body structure. The depth of the groove along the axial direction of the EPB drive screw does not exceed 0.5 mm, while the width of the groove along the radial direction of the EPB drive screw remains consistent with the prior art. This design results in less cutting allowance at the flange root, higher overall screw strength, and reduced stress concentration. This effectively reduces the risk of head breakage due to stress concentration at the flange root during normal use of the EPB drive screw, extending the service life of the EPB drive screw with its thinner flange. Furthermore, since each groove has a semi-teardrop-shaped swept-body structure along the EPB drive screw's axial direction, it can be directly machined with standard tools and CNC programs using continuous feed, effectively shortening machining time and saving production costs. Attached Figure Description
[0018] Figure 1 This is a partial axial sectional view of an EPB drive screw in the prior art;
[0019] Figure 2 This is an axial sectional view of the EPB transmission screw in an embodiment of this utility model;
[0020] Figure 3 This is a side view of the EPB transmission screw in an embodiment of this utility model;
[0021] Figure 4 for Figure 2 A magnified view of a portion of point A in the middle.
[0022] Explanation of icon numbers:
[0023] 1. Head; 2. Rod; 3. Flange; 4. Groove; 5. Fillet; 6. Thread; d1. Depth of the groove in the axial direction of the EPB drive screw; d2. Depth of the fillet in the radial direction of the EPB drive screw; l. Distance between the end of the fillet away from the flange in the axial direction of the EPB drive screw and the end face of the flange facing the head. Detailed Implementation
[0024] 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.
[0025] In the description of this utility model, it should be noted that the terms "upper," "middle," "lower," "inner," "outer," "front," "rear," "left," and "right," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this utility model and for simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances. The implementation methods of this utility model will now be described based on its overall structure.
[0026] Please see Figures 2 to 4 This utility model discloses an EPB drive screw, which includes a head 1, a rod 2, and a flange 3 connected between the head 1 and the rod 2. The connection between the head 1 and the flange 3 forms a clear corner structure.
[0027] The clearing structure includes a plurality of grooves 4 recessed inward from the flange 3 along the axial direction toward the end face of the head 1, the plurality of grooves 4 being connected end to end around the head 1; in the axial direction of the EPB drive screw, the cross section of each groove 4 is a semi-teardrop-shaped swept body structure; in the axial direction of the EPB drive screw, the depth d1 of the groove 4 does not exceed 0.5mm.
[0028] In the above configuration, the EPB drive screw still includes a head 1, a rod 2, and a flange 3 connecting the head 1 and the rod 2. The connection between the head 1 and the flange 3 forms a clear corner structure. This clear corner structure includes multiple grooves 4 recessed inward from the flange 3 along the axial direction towards the end face of the head 1. These grooves 4 are connected end-to-end around the head 1. The difference is that each groove 4 has a semi-teardrop-shaped swept-body structure along the axial direction of the EPB drive screw. The depth d1 of the groove 4 along the axial direction of the EPB drive screw does not exceed 0.5 mm, while the groove 4 along the radial direction of the EPB drive screw... Some widths remain consistent with existing technologies, resulting in less cutting allowance at the root of flange 3 and higher overall screw strength. This effectively reduces the risk of head 1 breaking due to stress concentration at the root of flange 3 during normal use of the EPB drive screw, and further extends the service life of the EPB drive screw with a thinner flange 3. In addition, since the cross-section of each groove 4 along the axial direction of the EPB drive screw is a semi-teardrop-shaped swept body structure, it can be directly machined with standard tools and CNC machining programs to complete the machining of flange 3 and head 1 through continuous tool feed, which can effectively shorten the machining time and save production costs.
[0029] Please see Figure 2 and Figure 4 Specifically, in this embodiment, in the radial direction of the EPB drive screw, the end of the sweeping body structure away from the head 1 is pointed at the end adjacent to the head 1, which is more conducive to the cutting of the standard tool (i.e., from the outer peripheral surface of the flange 3 to its end face facing the head 1, then to the groove 4, and then cutting to form the outer peripheral surface of the head 1, etc.).
[0030] Specifically, in this embodiment, the thickness of the flange portion 3 is 5.5mm along the axial direction of the EPB drive screw, and the depth d1 of the groove portion 4 is 0.5mm, accounting for only 1 / 11 of the thickness of the flange portion 3. This effectively ensures the strength of the root of the flange portion 3, making it less likely for the head 1 of the EPB drive screw to break due to stress concentration at the root of the flange portion 3 during later use. Of course, in other embodiments, the thickness of the flange portion 3 can also be other values not exceeding 6mm. In other words, a design in which the cross-section of each groove portion 4 is a semi-teardrop-shaped swept body structure along the axial direction of the EPB drive screw, and the depth d1 of the groove portion 4 does not exceed 0.5mm, is more suitable for EPB drive screws with a small flange portion 3 thickness.
[0031] Please see Figure 4Specifically, in this embodiment, the connection between the head 1 and the flange 3 is transitioned by a rounded corner 5. The corner clearing structure is closer to the rod 2 than the rounded corner 5. That is, in the axial direction, the rounded corner 5 is located between the corner clearing structure and the end of the head 1 away from the flange 3.
[0032] Specifically, in this embodiment, since the flange 3 and head 1 are machined directly using standard cutting tools and CNC machining programs through continuous tool feed, the corner clearing structure and fillet 5 located between the flange 3 and head 1 are smoothly connected without any steps (caused by tool changes). Furthermore, to ensure the smooth connection between the corner clearing structure and fillet 5, the depth d2 of the fillet 5 in the radial direction of the EPB drive screw does not exceed 0.2 mm, and the distance l between the end of the fillet 5 away from the flange 3 and the end face of the flange 3 facing the head 1 in the axial direction of the EPB drive screw does not exceed 0.5 mm.
[0033] Please see Figure 2 Specifically, in this embodiment, the outer wall of the rod 2 is also formed with threads 6, which is also formed by continuous cutting through a standard tool and CNC machining program.
[0034] Specifically, in this embodiment, the rod 2, head 1, corner clearing structure and flange 3 are integrally formed by CNC machining. During the forming process, the standard tool moves from one end of the rod 2 to the other end of the flange 3 along its outer wall surface according to the set CNC machining program.
[0035] Specifically, this embodiment also provides an EPB caliper assembly (not shown in the figure), including the EPB drive screw as described above. The actuator assembly included in the EPB caliper assembly drives the EPB drive screw and screw sleeve to move, so that the caliper body clamps or releases the brake disc. During this process, the EPB drive screw is less likely to break at the head 1 from the root of the flange 3, thereby making the braking of the EPB caliper assembly more stable.
[0036] Finally, it should be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any changes, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.
Claims
1. An EPB drive screw, characterized in that, It includes a head, a rod, and a flange connecting the head and the rod, wherein the connection between the head and the flange forms a clear corner structure; The clearing structure includes a plurality of grooves recessed inward from the end face of the flange portion toward the head along the axial direction, the plurality of grooves being connected end to end around the head; in the axial direction of the EPB drive screw, the cross-section of each groove portion is a semi-teardrop-shaped swept body structure; in the axial direction of the EPB drive screw, the depth of the groove portion does not exceed 0.5mm.
2. The EPB drive screw according to claim 1, characterized in that, In the radial direction of the EPB drive screw, the end of the sweeping body structure away from the head is pointed at the end adjacent to the head.
3. The EPB drive screw according to claim 1, characterized in that, The thickness of the flange portion in the axial direction of the EPB drive screw is no more than 6 mm.
4. The EPB drive screw according to claim 1, characterized in that, The connection between the head and the flange is rounded, and the corner structure is closer to the rod than the rounded corner.
5. The EPB drive screw according to claim 4, characterized in that, The corner clearing structure and rounded corners are smoothly connected.
6. The EPB drive screw according to claim 5, characterized in that, The depth of the fillet in the radial direction of the EPB drive screw does not exceed 0.2 mm.
7. The EPB drive screw according to claim 5, characterized in that, In the axial direction of the EPB drive screw, the distance between the end of the fillet away from the flange and the end face of the flange facing the head does not exceed 0.5 mm.
8. The EPB drive screw according to claim 1, characterized in that, The outer wall of the rod is also formed with threads.
9. The EPB drive screw according to claim 1, characterized in that, The rod, head, corner structure, and flange are all integrally formed using CNC machining.
10. An EPB caliper assembly, characterized in that, Includes the EPB drive screw as described in any one of claims 1 to 9.