The Development Of Automatic Vehicle Pointer Mounting Machine

The automobile electronic instrument reflects all the key state and data information of the automobile in the most intuitive form.For the accuracy and timeliness of the key control quantity displayed by the automobile instrument pointer,there is a very high requirement,which directly affects the driver's comfort and even safety.Therefore,the automotive instrument industry of china has paid more attention to pointer installation technology and development efforts.At the same time,it also serves as a reliable quality guarantee for products while improving the technology content and technology level of domestic automotive instruments.Firstly,aiming at the key structural coordination problems of pointer and motor when they are installed due to the reduction of raw material cost,practical and feasible solutions are put forward.It is determined that the lowest surface of the external connecting column is higher than the backlight of the dial,and the lowest depth driven by the inertial traction torque of the pointer is the reasonable selection criterion of the installation depth of the pointer.In order to meet the requirement of precise positioning of installation depth,the PLC servo precise positioning system is used as the basis of stroke control.A design scheme of applying negative feedback automatic positioning correction algorithm to stroke control is proposed to ensure the installation depth of instrument pointer.By analyzing the actual necessary production links,the optimum assembly mode of automobile instrument pointer installation is put forward.Secondly,in order to automatically judge whether the installat ion process is successful,and to minimize the error rate of artificial judgment,the design idea of self-determination method of instrument pointer pressure is put forward.Aiming at the problem of pointer-driven defect caused by abnormal contact force,a pressure monitoring platform for pointer installation was developed to precisely control and monitor the contact force of pointer and motor in actual installation.Then,according to the motor driving parameters provided by the motor manufacturer and the analysis of large number repaired instruments data,it is concluded that there are more sticking phenomena in the range of 10°,40°,210°after the pointer is installed.The detailed design scheme of instrument full-function testing after installation is put forward,and the automo bile instrument full-function signal source is developed.In order to transmit data stably under the condition of strong magnetic interference such as servo motor driver and high switching power supply,TJA1050 CAN bus is used as the internal communication carrier of the signal source to construct the data platform between the signal modules,and each signal module uses Fujitsu MB96F386 chip as the topology unit to control the transmission of corresponding signals.Finally,in order to verify whether the subject can solve the key problems of installation depth,installation strength and installation angle in the process of instrument pointer installation,and achieve the expected process design standard,the corresponding functional test experiment is designed to verify the effect,and the experimental results are listed.After the experiment is passed,more than 9000 sets of instruments installed by the equipment are taken as samples,and the matching degree,vibration,rotation,high and low temperature aging of the instrument pointer and motor are tested to further verify the practicability of the equipment.