Machine control circuit is my school maintenance electrician compulsory professional practice course , is a theory and practice are closely linked materials. The course through the introduction of several typical structure of the machine , action process , fault analysis and troubleshooting , so that students can master the machine control circuit design , choice of materials , principles of analysis and how to properly troubleshoot , so that students master the machine works and installation of wiring and process requirements , highlighting the practical . To enable students to learn in this course, improve the analysis and solution of practical problems capabilities, I combined with actual work on how to improve teaching machine control circuit to make some personal superficial view .
機床扼制線路是我校維修電工專業必須學習的實踐課程，是一門理論與實踐緊急銜接的教材。該課程經過紹介幾種典型機床的結構、動作過程、常見故障剖析及擯除辦法，可以使學生掌握機床扼制線路的預設、選料、原理剖析及怎么樣準確擯除故障，讓學生掌握了機床的辦公原理和安裝接線及工藝要求，突出了實踐性。

One can not be in the classroom presentation aspects of video recording, to students showing or to business, run factory site visits , increased perceptual knowledge
一、沒有辦法在課堂演出習的環節施行視頻文件錄制，給學生上映或到公司、校辦工廠實地參觀訪問，增加感性知識

        Because the machine equipment is relatively expensive , variety type and more general school equipment is insufficient to meet the teaching needs, but the school 's purpose is to train front-line teaching staff , student of the machine if the device is not an intuitive, emotional knowledge, pedagogical effect is certainly not will be ideal because simple to explain , analyze circuit schematics, students can not put the machine structure and movement pattern together. For example X62W universal milling machine lever operated by the two bench- six four limit switch direction , T68 boring one motor sport can drag multiple moving parts , the students difficult to understand , resulting in Theory and Practice of touch. Conversely, if the students before teaching eyes to see, touch devices , and operator assistance , hands-on equipment, machine tools to understand the structure and processing requirements , know the machine 's role in the actual production of which , such mobilization students' enthusiasm for learning and cultivate interest in learning , improve teaching quality and effectiveness. And this teaching students to understand the compliance characteristics of good teaching effect .
 由于機床設施比較極其昂貴，品品類型又比較多，普通學院設施不充足，沒有辦法滿意教學需要，但學院教學的目標是培育前線擔任職務的人，假如學生對機床設施沒有一個直觀的、感性的知識，教學效果肯定不會理想，由于天真解釋、剖析線路原理圖，學生不可以把機床結構與運動形式接合起來。

Second, on the basis of perceptual knowledge , focusing on theoretical analysis

        In speaking line troubleshooting tool when troubleshooting first clear the basic methods and ideas, through analysis of the line works to improve students' thinking ability , judgment and ability to analyze problems . So that students know troubleshooting critical step is to find a schematic diagram of the device , understand eating understand schematic diagram in the analysis when I asked the question using the side edges to explain, through a tacit understanding with students and teachers to complete the principles of analysis , the effect is good. For example when explaining T68 boring , the following several teaching :

(1) Introduction Original Role: This link can only SQ3, SQ1, SQ4, SQ2 role in detail, to lay the foundation for the line of principle , other elements have been involved in the front lines , the students have the ability to own analysis .

 (2) the line is divided into several major aspects of the overall
the main circuit section : From the main circuit can know what kind of control requirements, if any, is not reversing , braking, whether to take the buck starts and so on.

( 3) lighting circuits and indicating circuit part : This part of the circuit is relatively simple, almost any device which has a machine in question can be taken to explain the ways, such as the role of lighting circuits , HL lamp role .

 ( 4) auxiliary circuit Part 1: Introduction auxiliary line side can be used when analyzing while explaining the method, the analysis shows that the main circuit can slow reversing the spindle motor M1 , but also high-speed reversing.

 Upon completion of any of these three aspects were reviewed after a right boring principle , so that students master the knowledge more for the system , and thus the whole machine lines have a comprehensive understanding. That principle can be used when analyzing the line piecemeal approach , clear which part of the control circuit controls which part of the main circuit , the components of each part of the circuit , the formation of correct thinking, to exclude the machine fault lines and lay a good foundation.

Third, on the basis of theoretical analysis learned lines installed wiring and power test , the theory into practical skills

Machine line teaching content , not only to train students to design circuits and analysis capacity of the line , but also to pay attention to the actual operation , to provide students with adequate training materials and time, by wiring training to improve students' ability to master the machine control circuit wiring installation process requirements. To give students a solid grasp of basic skills , without a certain amount of training is mainly the . In addition, the installation wiring process, students working principle of the machine will be further analyzed , which improves the ability, but also to enable students to understand the theoretical knowledge and practical intrinsic link between , lay a solid foundation for future work .

Forth, line troubleshooting tool to take this teaching demonstration method

 Line troubleshooting tool both teaching process focus is difficult , in practice , once the machine there is an electrical fault , how maintenance, how to determine the maintenance procedure is very important. In addition to using the previous explain the law , made it clear troubleshooting specific ideas and methods in teaching before , should be ready to be a line troubleshooting analog board , the teacher in advance of the analog board set fault and demonstration operations, demonstrate troubleshooting process , this part requires students to focus on , to keep up with the teacher thinking . Such as the exclusion of T68 boring failure, set a hidden fault , through power-on test , observe the failure phenomenon , which will narrow the fault to the corresponding loop.

Fifth, the establishment of evaluation system

 their shortcomings , knowing what needs attention and improvement of the entire teaching process and student to grasp the situation also has an objective and impartial evaluation . And, one of the issues in a timely manner for each appraisal , you can always find and solve common problems students and improve teaching effectiveness and quality .

 Conclusion

 In the actual teaching process, often encounter a variety of problems , and how to enable students to put theory into practice and improve the correct and rational problem-solving abilities , full use of the knowledge , correctly principle analysis , design lines, installation wiring , commissioning and troubleshooting line , teachers can increase their exploratory instructional design to guide the students to ask questions and then tested through time , so as to achieve a full range of teaching purposes.