Automobile inspection tools are simple tools used by industrial production enterprises to control various sizes of products, such as apertures and space dimensions. It can improve production efficiency and control quality. It is suitable for mass-produced products. It replaces professional measurement tools in automotive parts, such as smooth plug gauges, threaded plug gauges, outer diameter gauges, etc. So what are the factors that need to be considered when designing automotive inspection fixtures?Design and manufacture of automobile inspection fixtures. Before the design of inspection fixtures, the concept of the design of the inspection fixtures should be clarified. The main considerations are:Fully understand GD & T, a descriptive document for automotive product design. Product specifications, product positioning benchmarks, key product characteristics, and product tolerance characteristics will be reflected on GD & T, so it must be fully understood before the design of the inspection fixture.Determine the positioning and testing content of the product, analyze the benchmark characteristics of the product positioning, consider the optimal placement of product parts, understand the meaning of various tolerances, determine the testing content that product parts must implement on the inspection fixture and do not need to be achieved or even impossible What is implemented.Statistics of process control capabilities, identifying whether the product has KPC requirements, CNC precision production to understand the purpose of the fixture, correctly understand the needs of quantitative measurement and qualitative measurement, and ensure the reliability of data collection.Understand the requirements and processes, fully understand the customer's requirements for product inspection tools, learn from past success or failure cases, fully understand the customer inspection tool review and approval process, and understand the required documents.The design principle of the gage should have sufficient rigidity; it should have sufficient stability; it should have sufficient measurement accuracy to ensure the quality of the car; the operation should be convenient to ensure sufficient measurement efficiency; the structure should be as simple as possible to use; It has sufficient economic guarantee to facilitate the control of vehicle costs; at the same time, it should be easy to measure and calibrate. The design points should have the common characteristics of the auto parts inspection tool, and also have its own characteristics. Its structure is mainly composed of the following parts: base plate and frame part, positioning device, clamping device, measuring device, auxiliary device, etc.
Measuring after the inspection tool is completed is a cumbersome step. Because the structure of the inspection tool is more complicated and the 3D surface has more measurement points, it is generally measured by the desktop three-coordinate. Although the accuracy of the desktop three-coordinate is high, it is inconvenient in operation, especially the partial inspection has a large specific product and many dead angles. The drawbacks of benchtop coordinate measurement have emerged. Therefore, another measurement method is known to everyone. This is the articulated arm coordinate measuring instrument, also called cmm arm, articulating arm, portable cmm arm, a measuring instrument that resembles a robot.A plurality of fixed length arms are interconnected by joints that rotate about mutually perpendicular axes, and a coordinate measuring device of the detection system is mounted on the final shaft. Generally, the number of rotations of the shoulders, elbows and wrists is represented by three "-" separated numbers. The 2-2-3 configuration can have a0-b0-d0-e0-f0 and a0-b0-c0-d0-e0 -f0-g0 The articulated arm measuring machine with angular rotation, in order to adapt to the current situation, the number of joints is generally less than 7, usually for manual measurement.The articulated arm measuring machine replaces the length reference with an angle reference, and connects several rods and one probe in series through a rotary joint, and the probe end moves freely in space, generally consisting of a base, 6 joints, 2 arms, and The measuring head and other parts are composed. The measuring system has a space of six degrees of freedom, which can easily realize the measurement of complex workpieces. The articulated arm coordinate measuring machine uses the rotation angle of each joint and the action arm as a measurement reference to realize coordinate measurement by coordinate system transformation. Therefore, the primary measured parameter in the data acquisition system is the corner of each joint, and the length of the working arm is determined by the calibration of the mechanical structure.
The setting of the lamp can realize the positioning of the gage and the lamp through the three positioning buckles of the three positioning slots on the gage, and fix the gage and the lamp by two locking handles. The six directions of the lamp ensure the positioning and fixing of the lamp and the gage during the measurement. All the positioning block and the locking block are limited by the space or directly below the lamp. From the perspective of cost saving and ease of use, the left and right parts of the lamp are designed on the same bottom plate without affecting the use.Due to the small size of the lamp, the curvature of the surface changes greatly, and the locking area and the positioning block are under the lamp, resulting in a deep and narrow area of the gage body to be processed, and the machine tool is in the space of processing the negative angle of the area. The restriction will interfere with the body of the gage, and at the same time, there is no operation space when the partial positioning block is actually installed.In order to solve this difficulty, the resin material can be combined in the design stage to facilitate the segmentation, easy bonding, and the ability to restore the overall strength after bonding. The module is decomposed from bottom to top, and the parts that interfere with the original machine tool are avoided by separate processing. After processing, the processing is continued by bonding. The operation space of the positioning block is not installed, and the fixture body module can be disassembled, the positioning block is first installed, and the subsequent inspection tool body module is assembled, and the process improvement is solved, which not only solves the processing interference problem, but also realizes the installation of the positioning block. It does not affect the accuracy and strength of the gage.
The support of the car inspection tool is very simple. In addition to the high precision of the analog block in all parts of the car inspection tool, the height accuracy of other parts is guaranteed to be plus or minus ±0.01MM, and the shape can be plus or minus 0.1mm. Within the scope of the part, the structure of the part is also very simple, which is a simple supporting part. Before processing, the material of the incoming material is first determined. The supporting support is made of steel and aluminum. According to the customer's product, Select the support base of different materials, first determine the dimensions of the incoming material during the processing, and whether the steel has a margin of 0.3~0.5MM.The milling machine starts to punch holes. In order to facilitate the subsequent processing, the support seat of the steel must be hit with the reference point. The positioning pin hole of the blind hole should be in place. The milling machine processes the pin hole and the screw hole and sends the heat treatment after the tapping is completed. The hardness is HRC45. °C~48°C, the standard parts of the support seat ordered on the general market are not hardened. In order to consider the service life of the parts, all the steel parts of the thick-rui vehicle inspection tools will be hardened. After the heat treatment is finished, the height of the support seat should be finely ground to ±0.01MM, the shape is ±0.1MM, the support surface has beveled and profiled wire cutting and NC machining. After all the processes are completed, the chamfer deburring is perfect. The car inspection tool zero sticker is processed.