Special clamp device for detecting automobile parts

Abstract

The invention relates to the technical field of automobile part detection, in particular to a special clamp device for automobile part detection, which comprises a base and a top seat, and the top seat and the base are arranged in parallel at an interval; the brackets are connected between the base and the top seat; the upper mounting rod is mounted at the top of the top seat; the lower mounting rod is mounted at an opening of the top seat; the spraying assemblies are mounted at the bottom of the upper mounting rod and the top of the lower mounting rod correspondingly; according to the invention, the jet assemblies which are opposite up and down are arranged, a non-contact lifting and pressing force field for a workpiece is formed by utilizing airflow, real non-contact fixation is realized, a detection blind area and a workpiece damage risk caused by clamp contact are thoroughly eliminated, and in the fixing process, the detection precision is greatly improved. The surface of the workpiece can be synchronously purged and cleaned through the air flow sprayed by the spraying assembly, attached impurities are effectively removed, a clean working surface is provided for subsequent high-precision detection, and the reliability of a detection result is improved.

Description

Technical Field

[0001] This invention relates to the field of automotive parts testing technology, and specifically to a special fixture device for automotive parts testing. Background Technology

[0002] Traditional fixtures face two prominent problems in the inspection of automotive interior parts, especially large and vulnerable headliner assemblies.

[0003] Firstly, traditional mechanical clamps or vacuum chucks must be in direct contact with the workpiece surface to provide clamping force. This contact can not only leave indentations or scratches on the clamped area, affecting the product's appearance quality, but more importantly, the contact area creates a blind spot for inspection, making it impossible to effectively inspect the surface quality and dimensions of that area. To complete comprehensive inspection, operators must repeatedly disassemble and adjust the workpiece position, a cumbersome process that easily introduces secondary positioning errors. Furthermore, for ceilings covered with delicate fabrics, leather, or special coatings, improper control of contact pressure can easily cause permanent damage, increasing production costs and quality risks.

[0004] Secondly, existing inspection stations typically lack online cleaning capabilities. During transport and clamping, parts easily accumulate dust, fibers, and other impurities on their surfaces. If high-precision optical inspection is performed directly, these impurities can be misidentified as product defects, leading to a higher false positive rate and severely impacting the accuracy of inspection results. Setting up a separate cleaning station not only increases production line length and cycle time, but the secondary handling of workpieces after cleaning and before inspection may also introduce new contamination. Therefore, efficiently and non-contactly completing surface cleaning while fixing the workpiece is crucial for improving the automation level and first-pass yield of the inspection process.

[0005] Therefore, there is an urgent need for a special fixture device that can avoid contact with the workpiece during the inspection process and simultaneously achieve cleaning, in order to solve the three interrelated pain points of blind spots in inspection, workpiece damage and surface cleanliness. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to overcome the problems of blind spots and workpiece damage caused by contact fixation during the inspection of automotive parts, especially large interior parts such as headliners, and the need for additional cleaning procedures before inspection, which affect efficiency and accuracy. The present invention provides a special fixture device that can achieve non-contact fixation, synchronous online cleaning and is highly adaptable.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows: a special fixture device for testing automotive parts, comprising a base and a top seat arranged parallel to and spaced apart therefrom; a plurality of brackets vertically connected between the base and the top seat; an upper mounting rod installed on the top of the top seat and a lower mounting rod installed at the opening of the top seat; a plurality of injection components, respectively installed at the bottom of the upper mounting rod and the top of the lower mounting rod, for generating airflows in opposite directions; a carrier plate, fixedly connected to the brackets, on which an air pump is mounted; an air extraction pipeline, including a main air extraction pipe connected to the input end of the air pump and a secondary air extraction pipe connected to the main air extraction pipe and embedded in the bracket; and an exhaust pipe, one end of which is connected to the output end of the air pump, and the other end of which is connected to the input end of each injection component through an air path branch.

[0008] Each spraying component includes: a fixed base, serving as a mounting carrier; a nozzle, located at the end of the fixed base, with annular cleaning micro-holes on its periphery; a drive mechanism, located inside the fixed base, with its output end connected to the nozzle for driving the nozzle to rotate around its axis; a regulating valve, located inside the fixed base, with its input end connected to the exhaust pipe and its output end connected to the nozzle's input port via a connecting pipe, for independently regulating the airflow of the spraying component; and an infrared distance sensor located at the end of the fixed base, for real-time detection of the distance between the nozzle and the workpiece surface.

[0009] Furthermore, the top of the top seat is equipped with at least two support seats, with the upper mounting rod installed between the two support seats to enhance structural stability. The top of the base has at least two limiting grooves and a receiving box that can be pulled along the limiting grooves. The bottom of the receiving box has a limiting strip that slides with the limiting grooves, facilitating the collection and cleaning of larger particles. The end of the exhaust pipe is connected to a dust-collecting ring fixedly installed on the top of the top seat. The surface of the dust-collecting ring has micropores to create a local negative pressure zone above the workpiece, efficiently collecting suspended dust. The bottom of the carrier plate is also equipped with a discharge hopper connected to the output end of the air pump, and a first solenoid valve is installed at the connection point to achieve reverse airflow, used for periodic cleaning of the discharge hopper or strong dust removal.

[0010] Preferably, the drive mechanism is a servo motor fixedly installed within the cavity of the mounting base. The output end of the servo motor is fixedly connected to the rotating shaft of the nozzle via a coupling or reduction mechanism, achieving precise and controllable rotation of the nozzle angle. The end face of the mounting base has an annular connecting ring, the inner cavity of which is connected to the input port of the nozzle via an internal flow channel; the output end of the regulating valve is connected to the inner cavity of this connecting ring via a flexible connecting pipe. This design achieves a dynamic sealing connection between the rotating nozzle and the fixed air path, ensuring a continuous and stable supply of airflow when the nozzle rotates. The regulating valve is specifically a proportional valve, installed at the bottom of the cavity of the mounting base, facilitating wiring layout and maintenance.

[0011] The beneficial effects of this invention are as follows: By using the coordinated action of the upper and lower spray components, the workpiece (such as a car roof) is completely detached from physical contact and suspended in place. This fundamentally solves the two major problems of blind spots and surface damage caused by contact fixtures, allowing the upper and lower surfaces of the workpiece to be fully and unobstructedly exposed to various inspection devices (such as 3D scanners and vision cameras), ensuring the comprehensiveness and accuracy of the inspection.

[0012] The system utilizes the main airflow ejected from the nozzle for suspension and fixation, while simultaneously dispersing airflow through annular cleaning micro-holes on its periphery, which can drive the nozzle to rotate, achieving active sweeping cleaning of the workpiece surface. The cleaning process and fixation process are carried out simultaneously, requiring no additional steps or time, significantly improving the continuity and efficiency of the inspection process, and ensuring that the inspection is performed on a clean surface, greatly reducing the risk of false detections and missed detections caused by impurities.

[0013] Each spraying assembly integrates an infrared ranging sensor that detects its relative position to the workpiece surface in real time and feeds the signal back to the control system. Based on the feedback data from each sensor, the control system independently and dynamically adjusts the opening of the corresponding proportional valve, thereby precisely controlling the airflow at each point. This allows the device to automatically adapt to workpieces of different sizes, initial postures, or with slight deformations, intelligently compensating for differences and always maintaining the workpiece in a preset optimal suspension state, enhancing the equipment's versatility and stability.

[0014] The system utilizes an exhaust pipe, a dust collection ring, and a receiving box to form a complete pollutant treatment chain, from purging and negative pressure adsorption to material collection. This not only effectively controls secondary pollution generated during the cleaning process and maintains a clean working environment, meeting the environmental protection requirements of modern production workshops, but also demonstrates the systematic and comprehensive nature of the equipment design. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0016] Figure 1 The diagram shown is a first-view structural schematic of the present invention. Figure 2 The diagram shown is a schematic diagram of the overall second-view structure of the present invention; Figure 3 The diagram shown is a schematic diagram of the top seat structure of the present invention; Figure 4 The diagram shown is a schematic diagram of the connection structure between the air pump and several injection components of the present invention. Figure 5The diagram shown is a schematic representation of the external structure of the spray assembly of the present invention. Figure 6 The diagram shown is a front cross-sectional view of the spray assembly of the present invention.

[0017] The labels in the diagram represent: 1. Base; 2. Air pump; 3. Fixing seat; 11. Top seat; 12. Bracket; 13. Support seat; 14. Upper mounting rod; 15. Limiting slide groove; 16. Lower mounting rod; 17. Carrier plate; 18. Receiving box; 19. Limiting strip; 21. Discharge hopper; 22. Main exhaust pipe; 23. Secondary exhaust pipe; 24. Dust suction ring; 25. Exhaust pipe; 31. Nozzle; 32. Annular cleaning micro-hole; 33. Infrared transmitter; 34. Infrared receiver; 35. Servo motor; 36. Connecting ring; 37. Proportional valve. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0019] The present invention will be further described below with reference to embodiments. Example

[0020] The basic structure of a special fixture device for inspecting automotive parts. For example... Figures 1 to 6 As shown, the device mainly includes a frame structure, an exhaust system, and a core injection component.

[0021] The frame structure consists of a base 1, a top seat 11, and several vertical supports 12. The base 1 is placed horizontally, serving as the mounting base for the entire device. The top seat 11 is fixed directly above the base 1 by the supports 12, maintaining parallelism and a certain distance between them to form an open working chamber. A rectangular opening is machined in the central area of ​​the top seat 11. Two support seats 13 arranged along their length are fixedly installed on the top surface of the top seat 11. Between these two support seats 13, several parallel upper mounting rods 14 are horizontally mounted. At the same time, several parallel lower mounting rods 16 are also horizontally fixed inside the two long sides of the rectangular opening of the top seat 11. The lower mounting rods 16 are located directly below the upper mounting rods 14. The top surface of the base 1 is machined with two parallel limiting grooves 15. A top-open receiving box 18 is slidably mounted in these limiting grooves 15 via two limiting strips 19 at its bottom, and can be pulled out as a whole to dump waste materials.

[0022] The air supply and exhaust system is integrated into the frame. A carrier plate 17 is fixedly mounted on a bracket 12 on the side via connectors. An air pump 2 is mounted on the top of the carrier plate 17. The input end of the air pump 2 is connected to a main suction pipe 22, which is arranged along the bracket 12. Inside the bracket 12, a secondary suction pipe 23 is pre-embedded, one end of which is connected to the main suction pipe 22. On the top surface of the top seat 11, a hollow dust collection ring 24 is installed around its central opening. The internal cavity of the dust collection ring 24 is connected to the other end of the secondary suction pipe 23, and the upper surface of the dust collection ring 24 is covered with tiny dust collection holes. The main output end of the air pump 2 is connected to an exhaust pipe 25, which branches into multiple branch pipes after exiting the air pump 2. In addition, a discharge hopper 21 is installed at the bottom of the carrier plate 17, and the discharge hopper 21 is connected to the other output end of the air pump 2 via a pipe equipped with a first solenoid valve.

[0023] The core spraying assembly is divided into two groups, upper and lower. One group of spraying assemblies is mounted on the top of the lower mounting rod 16 via its mounting base 3, with the nozzle 31 facing upwards; the other group of spraying assemblies is mounted on the bottom of the upper mounting rod 14 via its mounting base 3, with the nozzle 31 facing downwards. The upper and lower nozzles are corresponding in the vertical direction.

[0024] The specific internal structure of each jet assembly is as follows: Figure 5 and Figure 6As shown. The mounting base 3 is a hollow shell. The nozzle 31 is mounted on the end of the mounting base 3 via bearings, allowing it to rotate around its own axis. The center of the nozzle 31 is the main spray hole, and a ring of annular cleaning micro-holes 32 is opened around its cylindrical surface. A servo motor 35 is installed inside the cavity of the mounting base 3. The output shaft of the servo motor 35 is directly connected to the rotating shaft of the nozzle 31 via a miniature coupling, thereby driving the nozzle 31 to rotate. A proportional valve 37 is installed at the bottom of the cavity of the mounting base 3. The air inlet of the proportional valve 37 is connected to the corresponding branch pipe of the exhaust pipe 25 via a pipeline. An annular connecting ring 36 is press-fitted onto the end face of the mounting base 3. The annular connecting ring 36 is fixedly embedded in the groove on the end face of the mounting base 3, with an O-ring seal provided to achieve static sealing. A precise annular gap is formed between the inner wall of the connecting ring 36 and the outer wall of the air inlet port of the nozzle 31, or a miniature rotating sealing ring is installed, thereby achieving dynamic sealing and maintaining air passage continuity when the nozzle 31 rotates. The inner cavity of the connecting ring 36 is connected to the air inlet port of the nozzle 31 through a drilled hole inside the fixed base 3. The air outlet of the proportional valve 37 is connected to the inner wall of the connecting ring 36 through a flexible silicone tube, thereby delivering airflow to the rotatable nozzle 31. On both sides of the end of the fixed base 3 where the nozzle 31 is installed, an infrared emitter 33 and an infrared receiver 34 are respectively embedded. The infrared emitter 33 and the infrared receiver 34 are installed side by side at a small angle, both facing the workpiece surface. After the emitted light is diffusely reflected by the workpiece surface, part of it is received by the infrared receiver 34. The intensity of the received light varies with distance, thereby allowing for distance measurement.

[0025] The device also includes a control system (not shown in the figure), which can be a programmable logic controller (PLC) or an industrial computer. The input ports of the control system are connected to all infrared transmitters 33 and infrared receivers 34 via cables, and its output ports are connected to all proportional valves 37, servo motors 35, air pump 2, and the first solenoid valve via drive circuits. The control system pre-stores the target suspension height parameters of the workpiece and the control algorithm.

[0026] The work process is as follows: Before the inspection begins, the operator horizontally hoists the car roof workpiece into the working chamber between the base 1 and the top seat 11, placing it roughly in the center. The air pump 2 is started, and compressed air is delivered through the exhaust pipe 25 to the proportional valve 37 of each injection component, and then enters the nozzle 31 through the connecting ring 36.

[0027] The lower spray assembly ejects a concentrated airflow upwards from its nozzles 31. This airflow impacts the lower surface of the ceiling, forming an air cushion that generates an upward lifting force. The upper spray assembly ejects airflow downwards from its nozzles 31, applying downward pressure to the upper surface of the ceiling. The combined action of the upper and lower airflows overcomes the workpiece's gravity, keeping it stably suspended at a balance position a certain distance from the nozzles. During this process, the infrared emitter 33 of each spray assembly continuously emits infrared light, which is reflected by the ceiling surface and received by the infrared receiver 34 of the same assembly. The control system processes the signals from all infrared sensors in real time, calculating the real-time distance between the nozzle 31 and the workpiece surface at each measurement point.

[0028] The control system processes signals from all infrared ranging sensors in real time, calculating the deviation between the actual workpiece position and the preset target position at each measurement point. Based on a preset PID control algorithm, the control system calculates the required opening adjustment for each proportional valve 37. For example, when the system detects that the workpiece position in a certain area is too low, it increases the opening of the proportional valve 37 of the injection assembly below that area to enhance the lifting force, and may simultaneously decrease the opening of the proportional valve 37 of the injection assembly above that area to balance the pressure, thereby smoothly adjusting the workpiece in that area to the target height. This is achieved through multi-input, multi-output closed-loop feedback control.

[0029] When surface cleaning is required, the control system issues a command. The servo motors 35 of all spray components activate, driving the nozzles 31 to oscillate periodically at a certain angle (e.g., ±30 degrees). Simultaneously, the system can control the proportional valve 37 to direct a portion of the airflow more towards the annular cleaning micro-holes 32 surrounding the nozzles 31. The oscillating nozzles 31, in conjunction with the diffused cleaning airflow, efficiently sweep and blow across the upper and lower surfaces of the ceiling, removing most of the attached dust and fibers.

[0030] During the cleaning process, air pump 2 continuously draws air from suction ring 24 through main suction pipe 22 and secondary suction pipe 23, creating a localized negative pressure zone above the ceiling. Lighter dust particles blown up are drawn into the micropores of suction ring 24 by the airflow, enter the suction pipe, and are ultimately captured by the filter before air pump 2. Heavier particles or debris that are not sucked up fall downwards under gravity into the collection box 18 on base 1. If a large amount of debris accumulates in the collection box 18, it can be manually pulled out along the limiting slide groove 15 for cleaning.

[0031] Throughout the inspection, the canopy remains in a clean, stable, and contactless suspended state. Inspection equipment (such as a mobile 3D scanning arm or a top-mounted camera) can perform unobstructed comprehensive scanning and measurement of the workpiece's upper and lower surfaces. After inspection, the control system sequentially closes proportional valve 37 and air pump 2, and the canopy slowly and smoothly descends under gravity onto a soft support pad pre-placed on base 1, where it is safely removed by operators or a robotic arm. Example

[0032] Based on Embodiment 1, this embodiment provides an implementation method with functional expansion and performance optimization. Its overall framework and exhaust system are the same as those in Embodiment 1. The main differences are in the driving method of the injection component, the air path control strategy, and the enhancement of the dust collection function.

[0033] Firstly, this embodiment provides an alternative solution for the drive mechanism of the injection assembly. Instead of using a servo motor 35, the drive mechanism within the mounting base 3 is replaced by a shape memory alloy (SMA) wire drive mechanism. Specifically, within the mounting base 3, the rotation axis of the nozzle 31 is connected to the base of the mounting base 3 via a two-dimensional flexible hinge. Four SMA wire actuators are symmetrically arranged around the X and Y axes of this flexible hinge. One end of each SMA wire is fixed to a specific point on the flexible hinge, and the other end is fixed to the base of the mounting base 3. By electrically heating different combinations of SMA wires, they contract, thereby pulling the flexible hinge to produce precise elastic deformation, driving the nozzle 31 to oscillate in both pitch and yaw degrees of freedom. The oscillation mode can be flexibly defined through an electronic control program.

[0034] Secondly, in terms of airflow control, the regulating valve in this embodiment employs a combination of a high-speed switching valve and a proportional valve 37. Within each fixed seat 3 cavity, a high-speed switching valve is connected in series before the air inlet of the proportional valve 37. The high-speed switching valve generates a high-frequency pulsed airflow, while the proportional valve 37 precisely regulates the average flow rate. This combination generates a high-frequency vibrating airflow in cleaning mode, more effectively shaking off stubborn deposits.

[0035] Furthermore, the dust collection function is enhanced. In this embodiment, the interior of the suction ring 24 is divided into four independent air chambers, each connected to an independent auxiliary suction pipe 23 branch, and connected to the main suction pipe 22 via an independently controlled second solenoid valve. Simultaneously, a flip-up mesh baffle is added at the upper inlet of the discharge hopper 21. Normally closed to prevent debris from falling directly into the bottom pipe of the discharge hopper 21, it is opened only when strong dust removal is required.

[0036] The work process is as follows: The basic suspension and fixation process is similar to that in Example 1. However, during the cleaning phase, its operating modes are more diverse and efficient.

[0037] When the deep cleaning mode is activated, the control system first drives the shape memory alloy wire according to a preset program, adjusting all nozzles 31 to an optimal initial angle, such as slightly tilting them outwards to facilitate blowing dust towards the edges. Subsequently, the high-speed switching valves of all spray components operate in a high-frequency (e.g., 50Hz) pulse mode, while the proportional valve 37 maintains the basic suspended flow rate based on feedback from the infrared sensor. The pulsed airflow is ejected from the main nozzle orifice of the nozzle 31 and the annular cleaning micro-holes 32, generating high-frequency micro-impacts on the ceiling surface, effectively loosening tightly adhered particles.

[0038] Simultaneously, the control system can control the nozzles in different areas to swing in coordination. For example, first, the nozzle 31 located in the middle is controlled to swing to one side, blowing dust to one side edge; then, the nozzle 31 located on that side edge is controlled to tilt downwards, cooperating with the independently opened air chamber of the suction ring 24 in that area (by opening the corresponding second solenoid valve), forming a powerful directional blowing and collecting flow field, efficiently sucking the dust gathered at the edge into the suction ring 24.

[0039] For larger particles collected in the receiving box 18, cleaning is more convenient in this embodiment. During testing breaks, the operator can pull out the receiving box 18 and empty it directly. If it is necessary to clean the pipe or discharge hopper 21, other air lines can be closed, and the first solenoid valve on the pipe connected to the discharge hopper 21 can be opened separately, along with the mesh baffle above the discharge hopper 21. The high-pressure gas output by the air pump 2 flows in reverse into the discharge hopper 21 and the short pipe connected to it, blowing out any accumulated dust and achieving self-cleaning.

[0040] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions will not cause the essence of the corresponding technical solutions to deviate from the protection scope of the technical solutions of the embodiments of the present invention.

Claims

1. A special fixture device for inspecting automotive parts, characterized in that, include: A base (1) and a top seat (11) arranged parallel to and spaced apart from it; Several brackets (12) are connected between the base (1) and the top seat (11); An upper mounting rod (14) is installed on the top of the top seat (11) and a lower mounting rod (16) is installed at the opening of the top seat (11). Several spraying components are respectively installed at the bottom of the upper mounting rod (14) and the top of the lower mounting rod (16); The carrier plate (17) is fixedly connected to the bracket (12), and an air pump (2) is provided on it. The air extraction pipeline includes a main air extraction pipe (22) connected to the input end of the air pump (2) and a secondary air extraction pipe (23) connected to the main air extraction pipe (22) and embedded in the bracket (12). The exhaust pipe (25) is connected at one end to the output end of the air pump (2) and at the other end to the input end of each of the injection components.

2. The special fixture device for inspecting automotive parts according to claim 1, characterized in that, Each of the aforementioned injection components includes: Fixed base (3); The nozzle (31) is located at the end of the fixed base (3), and its periphery is provided with annular cleaning micro-holes (32). The drive mechanism is located inside the fixed base (3), and its output end is connected to the nozzle (31) to drive the nozzle (31) to rotate. The regulating valve is located in the fixed seat (3), with its input end connected to the exhaust pipe (25) and its output end connected to the input port of the nozzle (31) through the connecting pipe; An infrared ranging sensor is integrated at the end of the mounting base (3) and specifically includes an infrared transmitter (33) and an infrared receiver (34).

3. The special fixture device for inspecting automotive parts according to claim 1, characterized in that, The top of the top seat (11) is also provided with at least two support seats (13), and the upper mounting rod (14) is installed between the two support seats (13).

4. The special fixture device for inspecting automotive parts according to claim 1, characterized in that, The base (1) has at least two limiting grooves (15) on its top and a receiving box (18) with a limiting strip (19) at the bottom that slides in cooperation with the limiting grooves (15).

5. The special fixture device for inspecting automotive parts according to claim 1, characterized in that, The exhaust pipe (23) is connected to a dust collection ring (24) installed on the top of the top seat (11).

6. The special fixture device for inspecting automotive parts according to claim 1, characterized in that, The bottom of the carrier plate (17) is also provided with a discharge hopper (21) that is connected to the output end of the air pump (2), and a first solenoid valve is provided at the connection point.

7. The special fixture device for inspecting automotive parts according to claim 1, characterized in that, The drive mechanism includes a servo motor (35) fixedly installed in the cavity of the fixed base (3), and the output end of the servo motor (35) is fixedly connected to the nozzle (31).

8. The special fixture device for inspecting automotive parts according to claim 2, characterized in that, The end face of the fixed seat (3) is provided with an annular connecting ring (36). The inner cavity of the connecting ring (36) is connected to the input port of the nozzle (31). The output end of the regulating valve is connected to the inner cavity of the connecting ring (36) through a connecting pipe.

9. The special fixture device for inspecting automotive parts according to claim 8, characterized in that, The regulating valve is a proportional valve (37) and is installed at the bottom of the cavity of the fixed seat (3).

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