A profile reference surface processing apparatus for an automotive hinge

Abstract

The application discloses a profile reference surface machining equipment for automobile hinges and relates to the technical field of automobile part machining equipment, in particular to the profile reference surface machining equipment which specifically comprises a rack, a front pinch roller group, a cutting station and a rear pinch roller group arranged on the rack along a preset profile conveying path in sequence, synchronous action between the front pinch roller group and the rear pinch roller group is used for clamping the profile to feed along the conveying path at a preset constant linear velocity and limit the longitudinal movement of the profile, and the cutting station is provided with a cutting fly cutter which is suspended above the profile conveying path and rotates around a vertical axis, wherein the cutting edge of the cutting fly cutter acts on the top surface of the profile to perform rotary cutting on the top surface of the continuously fed profile, and a reference surface meeting the accuracy requirement is formed by one-time machining.

Description

Technical Field

[0001] This invention relates to the technical field of automotive parts processing equipment, and more particularly to a profile reference surface processing equipment for automotive hinges. Background Technology

[0002] Automotive hinges are core safety structural components connecting car doors to the car body. They must simultaneously meet three core requirements: bearing the weight of the door, remaining undeformed after more than 200,000 opening and closing cycles, and not detaching or failing in a side impact. The reference surface of the hot-rolled steel used in hinges serves as the positioning reference for subsequent shaft hole machining and component assembly. The industry mandates that the flatness of the reference surface be ≤0.01mm, the surface roughness Ra≤1.6μm, and the batch accuracy deviation must not exceed 0.005mm. Otherwise, problems such as excessive hinge assembly clearance, excessive fluctuations in opening and closing torque, and even structural failure in a collision may occur.

[0003] Currently, the machining of the reference surface of automotive hinge steel generally adopts the following traditional process, which has unresolved industry pain points: Single-piece cutting machine processing: The process route is "hot-rolled long steel section → fixed-length cutting into single-piece blanks → clamping each piece onto a milling machine / grinding machine → milling / grinding of the reference surface → disassembly and unloading". This process has drawbacks such as extremely low efficiency, large accuracy fluctuations, and high material loss. Specifically, 1) the single-piece clamping, processing, and disassembly cycle is about 30 seconds, and the single-line capacity is only 2 pieces / minute, which cannot meet the needs of large-scale mass production; 2) the positioning error caused by repeated clamping accumulates, resulting in a low batch pass rate; 3) the head and tail material loss caused by fixed-length cutting is high, and a processing allowance of more than 0.5mm needs to be reserved for each piece to offset the clamping error, and the material utilization rate is more than 10% lower than that of continuous processing.

[0004] Currently, there is no mature process solution that can simultaneously meet the accuracy requirements of the reference surface of automotive hinge steel and the requirements of mass production efficiency, which has become the core bottleneck restricting the industry from reducing costs and increasing efficiency. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a continuous, high-precision, and high-efficiency machining equipment for the reference surface of automotive hinge steel.

[0006] To achieve the above objectives, the present invention provides a profile reference surface processing device for automotive hinges, comprising a frame, and a front clamping roller group, a cutting station, and a rear clamping roller group arranged sequentially on the frame along a preset profile conveying path. The front clamping roller group and the rear clamping roller group operate synchronously to clamp the profile and feed it uniformly along the conveying path at a preset constant linear velocity, thereby limiting the longitudinal movement of the profile. The cutting station is provided with a cutting blade suspended above the profile conveying path and rotating about a vertical fixed axis. The cutting edge of the cutting blade acts on the top surface of the profile to perform rotary cutting on the continuously fed top surface of the profile, thereby forming a reference surface that meets the accuracy requirements in one pass.

[0007] Furthermore, both the front pinch roller group and the rear pinch roller group include at least one pair of upper pinch rollers and lower support rollers that are positioned vertically opposite each other. The upper pinch rollers and lower support rollers of the same pair have synchronous linear speeds. The profile passes through the gap between the roller surfaces of the upper pinch rollers and the lower support rollers and is continuously fed by the friction of the roller surfaces.

[0008] Furthermore, the front pinch roller group and the rear pinch roller group share a set of power drive components, wherein the power drive components include a drive motor, a front linkage gear and a rear linkage gear, and the output shaft of the motor is synchronously connected to the front linkage gear and the rear linkage gear through a transmission chain. The front linkage gear simultaneously meshes with the upper pinch roller and / or the lower support roller of the front pinch roller group, and the rear linkage gear simultaneously meshes with the upper pinch roller and / or the lower support roller of the rear pinch roller group.

[0009] Furthermore, the frame is also provided with at least two sets of side guide limiting rollers respectively arranged on the left and right sides of the profile conveying path, wherein the roller surface of each side guide limiting roller set abuts against the side wall of the profile to limit the lateral displacement of the profile.

[0010] Furthermore, the cutting station is also provided with a receiving plate located below the profile conveying path and arranged at a downward angle, the receiving plate being used to receive metal chips generated during cutting.

[0011] The present invention adopts the above-mentioned solution, and its beneficial effects are as follows: 1) It realizes online continuous processing of long profiles without the need for fixed-length cutting and clamping one piece at a time, which greatly improves production efficiency; 2) The front and rear synchronous clamping forms bidirectional positioning to eliminate cantilever vibration, the side guide in the cutting zone offsets the lateral cutting force, and the speed matching realizes pure cutting without slippage, achieving precise processing of the flatness of the reference surface and greatly improving the processing quality; 3) The front clamping roller group and the rear clamping roller group share a set of power drive components, which reduces the equipment cost and improves economic efficiency. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the equipment for processing profile reference surfaces.

[0013] Figure 2 This is a schematic diagram of the equipment for processing profile reference surfaces.

[0014] Figure 3 This is a cross-sectional view of the profile reference surface processing equipment at the front and rear clamping roller groups.

[0015] Figure 4 This is a longitudinal cross-sectional view of the profile reference surface processing equipment at the side guide limit roller group.

[0016] Figure 5 This is a cross-sectional view of the profile reference surface processing equipment at the side guide limit roller group.

[0017] Among them, 1-frame, 2-front pinch roller group, 3-rear pinch roller group, 4-cutting fly knife, 5-side guide and limit roller group, 6-power drive assembly, 7-receiving plate, 21-upper pinch roller, 22-lower support roller, A-profile. Detailed Implementation

[0018] To more fully illustrate the present invention, a detailed description will be provided below in conjunction with the accompanying drawings. The drawings illustrate preferred embodiments of the invention. However, it is worth noting that the present invention is not limited to these specific forms and can be implemented in various ways. These embodiments are provided to enable the reader to gain a deeper understanding of the present invention.

[0019] See appendix Figure 1-5 As shown in this embodiment, a profile reference surface processing device for automotive hinges addresses the requirements for reference surface processing of profiles used in existing automotive door hinges, solving the problems of low efficiency and large accuracy fluctuations in the traditional independent processing of single profile reference surfaces. Specifically, it includes a frame 1, and a front clamping roller group 2, a cutting station, and a rear clamping roller group 3 arranged sequentially on the frame 1 along a preset profile conveying path. Both the front clamping roller group 2 and the rear clamping roller group 3 include two pairs of upper clamping rollers 21 and lower support rollers 22 positioned vertically opposite each other. The upper clamping rollers 21 and lower support rollers 22 of the same pair have synchronized linear speeds. Profile A passes through the gap between the roller surfaces of the upper clamping rollers 21 and lower support rollers 22, and is continuously fed by the frictional force of the roller surfaces.

[0020] Furthermore, the gap between the upper clamping roller 21 and the lower support roller 22 is slightly smaller than the thickness of the profile A, so as to provide clamping friction force to drive continuous feeding. At the same time, the clamping action of the upper clamping roller 21 and the lower support roller 22 is used to limit the longitudinal movement of the profile A.

[0021] In this embodiment, the front pinch roller group 2 and the rear pinch roller group 3 share a set of power drive assembly 6. The power drive assembly 6 includes a drive motor (preferably a servo motor), a front linkage gear, and a rear linkage gear. The output shaft of the drive motor is synchronously connected to the front linkage gear and the rear linkage gear through a transmission chain. The front linkage gear simultaneously meshes with the upper pinch roller 21 and / or the lower support roller 22 of the front pinch roller group 2, and the rear linkage gear simultaneously meshes with the upper pinch roller 21 and / or the lower support roller 22 of the rear pinch roller group 3. Specifically, in this embodiment, the front linkage gear meshes simultaneously with the upper synchronous gears preset at the ends of the two pairs of upper pinching rollers 21 of the front pinching roller group 2 (at this time, the front linkage gear is between the two upper synchronous gears). The upper synchronous gear at the end of the upper pinching roller 21 meshes with the lower synchronous gear preset at the end of the lower pinching roller. Thus, the power output by the drive motor is transmitted to the upper synchronous gear through the transmission chain, the front linkage gear and the rear linkage gear, so that each pair of upper pinching rollers 21 and lower support rollers 22 cooperate synchronously to continuously pinch the profile A, ensuring that the profile A maintains a uniform feeding speed.

[0022] In this embodiment, a cutting fly knife 4 is provided at the cutting station, which is suspended above the profile conveying path and rotates around a vertical fixed axis. In this embodiment, the cutting fly knife 4 is a vertical rotating disc fly knife with three hard blades evenly arranged around its bottom. Those skilled in the art can select the appropriate blade material, geometric parameters and fly knife disc structure from the existing publicly available metal cutting tool selection manual according to the strength of the material being processed and the machining allowance requirements, and reproduce the cutting effect of this embodiment without creative labor.

[0023] In this embodiment, the cutting edge of the cutting fly knife 4 acts on the top surface of profile A to perform rotary cutting on the continuously fed top surface of profile A, forming a reference surface that meets the accuracy requirements in one pass. The cutting linear velocity of the rotary fly knife assembly is pre-matched with the feed linear velocity of the profile, ensuring that the relative velocity between the fly knife cutting edge and the top surface of the profile is a pure cutting velocity with no horizontal relative slippage. Specifically, the horizontal component of the cutting edge's linear velocity equals the feed linear velocity of the profile (equal in magnitude and direction). The trajectory of the cutting edge of the cutting fly knife 4 is a circle on a horizontal plane. The velocity of the cutting edge at any given moment can be decomposed into a "transverse component perpendicular to the feed direction of profile A" and a "longitudinal component parallel to the feed direction of profile A." Only when the longitudinal component of the cutting edge contacts the top surface of the profile is completely consistent with the feed velocity of the profile will there be no relative slippage between the cutting edge and the top surface of the profile along the feed direction. The cutting edge will only exert a vertically downward cutting action on the top surface of the profile, without any horizontal scraping. To facilitate understanding, a parameter example is provided below for further explanation: The feed rate of profile A is defined as 5 m / min, and the cutter diameter D = 160 mm. When the cutter speed is approximately n = 239 r / min, the linear velocity of the cutting edge is approximately V_cutter = πDn = 3.14 × 0.16 × 239 ≈ 120 m / min. Correspondingly, the longitudinal component V_longitudinal = V_cutter·sin2.39° = 120 × 0.0417 = 5 m / min. This perfectly satisfies the condition that the longitudinal component equals the feed rate at the moment of contact, resulting in no horizontal slippage and achieving a pure cutting effect without scratches on the machined surface. If the longitudinal velocity of the cutter is greater than the feed rate of profile A, the cutting edge will scrape forward against the machined surface; if the longitudinal velocity of the cutter is less than the feed rate of profile A, the cutting edge will push backward against the surface to be machined. Both situations will lead to scratches and chatter marks on the reference surface, and the surface roughness will not meet the requirements of automotive hinges.

[0024] In this embodiment, the frame 1 is also provided with at least two sets of side guide limiting roller groups 5 respectively arranged on the left and right sides of the profile conveying path. Here, in order to stabilize the conveying, the frame 1 is provided with eight sets of side guide limiting roller groups 5, which are symmetrically distributed in pairs on the left and right sides of the profile conveying path. Each set of side guide limiting roller groups 5 includes a side limiting roller and a bearing seat for pivotal engagement of the side limiting roller. The gap between the side limiting rollers synchronously distributed on the left and right sides of the profile conveying path is slightly smaller than the width of the profile A, so that the side limiting roller surface abuts against the side wall of the profile A to limit the lateral displacement of the profile.

[0025] In this embodiment, the roller surfaces of the upper clamping roller 21, the lower support roller 22, and the side limiting roller are all covered with Shore A70 polyurethane. The hardness of the polyurethane is adapted to the hardness of the side wall of the steel profile, so that it will not scratch the surface of the steel profile, nor will it cause positioning failure due to excessive deformation.

[0026] In this embodiment, a receiving plate 7 is also provided at the cutting station, which is located below the profile conveying path and is arranged at a downward angle. The receiving plate 7 is used to receive metal chips generated during cutting.

[0027] To facilitate understanding, the following explanation, in conjunction with a specific workflow, includes the following steps: Feeding stage: The front clamping roller group 2 first clamps the profile A billet and feeds it. When the front end of the profile A billet enters the rear clamping roller group 3, the two clamping roller groups form a front and rear bidirectional positioning. At this time, the cutting fly knife 4 starts and enters a stable processing state.

[0028] Cutting stage: The cutting fly knife 4 cuts the top surface of profile A once per revolution, and micro-cuts once to form a reference surface that meets the accuracy requirements.

[0029] Material output stage: The finished profile A is fed out by the rear clamping roller and can be directly connected to the subsequent fixed-length cutting process without secondary positioning, thus avoiding the error of reference transfer.

[0030] In addition, in other extended embodiments, for profiles A with different thicknesses or processing requirements, the gap between the clamping rollers and the height of the fly cutter can be adjusted to adapt them. The adjustment methods and structures are common knowledge in the field of machining. Those skilled in the art can refer to publicly available technical documents such as the "Metal Cutting Tool Design Manual", "Mechanical Design Manual", and "Servo Transmission System Design Specification" to obtain relevant parameters, which will not be elaborated here.

[0031] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any way. Any modifications or variations made by those skilled in the art, without departing from the scope of the present invention, using the disclosed technical content, are equivalent embodiments of the present invention. Therefore, all equivalent changes made based on the concept of the present invention without departing from the scope of the present invention should be covered within the protection scope of the present invention.

Claims

1. A profile reference surface processing device for automotive hinges, characterized in that: The machine includes a frame (1), and a front clamping roller group (2), a cutting station and a rear clamping roller group (3) arranged sequentially on the frame (1) along a preset profile conveying path: the front clamping roller group (2) and the rear clamping roller group (3) operate synchronously to clamp the profile (A) and feed it at a preset constant linear speed along the conveying path and restrict the longitudinal movement of the profile (A); the cutting station is provided with a cutting fly knife (4) suspended above the profile conveying path and rotating around a vertical fixed axis, wherein the cutting edge of the cutting fly knife (4) acts on the top surface of the profile (A) to perform rotary cutting on the continuously fed top surface of the profile (A) and form a reference surface that meets the accuracy requirements in one operation.

2. The profile reference surface processing equipment for automotive hinges according to claim 1, characterized in that: The front pinch roller group (2) and the rear pinch roller group (3) each include at least one pair of upper pinch rollers (21) and lower support rollers (22) that are positioned vertically opposite each other. The upper pinch rollers (21) and the lower support rollers (22) of the same pair have synchronized linear speeds. The profile (A) passes through the gap between the upper pinch rollers (21) and the lower support rollers (22) and is continuously fed by the friction of the roller surfaces.

3. The profile reference surface processing equipment for automotive hinges according to claim 2, characterized in that: The front pinch roller group (2) and the rear pinch roller group (3) share a set of power drive components (6). The power drive components (6) include a drive motor, a front linkage gear and a rear linkage gear. The output shaft of the motor is synchronously connected to the front linkage gear and the rear linkage gear through a transmission chain. The front linkage gear simultaneously meshes with the upper pinch roller (21) and / or the lower support roller (22) of the front pinch roller group (2). The rear linkage gear simultaneously meshes with the upper pinch roller (21) and / or the lower support roller (22) of the rear pinch roller group (3).

4. The profile reference surface processing equipment for automotive hinges according to claim 1, characterized in that: The frame (1) is also provided with at least two sets of side guide limiting roller groups (5) respectively arranged on the left and right sides of the profile conveying path, wherein the roller surface of each side guide limiting roller group (5) abuts against the side wall of the profile (A) to limit the lateral displacement of the profile.

5. The profile reference surface processing equipment for automotive hinges according to claim 1, characterized in that: The cutting station is also provided with a receiving plate (7) located below the profile conveying path and arranged downwards. The receiving plate (7) is used to receive metal chips generated during cutting.

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