Reconstruction and practice of teaching mode of mechanical design course in higher vocational colleges

Reconstruction and practice of teaching mode of mechanical design course in higher vocational colleges

According to the characteristics of mechanical design course in higher vocational colleges, combined with the training objectives of higher vocational education, this paper analyzes the present situation and existing problems of course teaching, carries out teaching reform and practice from the aspects of teaching concept, teaching content, course design, teaching methods and means, reconstructs a new teaching mode, and puts forward a unique viewpoint of integrating mechanical structure and decomposing training links, so as to change the present situation of "model practice teaching" and provide reference for curriculum reform in higher vocational colleges.

Paper Keywords: mechanical design; Teaching reform; Project teaching; Demonstration practice teaching

I. Introduction

The course reform of Mechanical Design strives to break through the traditional teaching mode, jump out of the strange circle of the existing project-oriented "model practice teaching" in higher vocational colleges, pay attention to integrating the practical links of mechanical structure and disassembly, enhance students' understanding of the structure, manufacturing and assembly process of parts, deepen students' comprehensive understanding of mechanical equipment, processing methods, processing accuracy, assembly accuracy, technical conditions and other engineering and technical knowledge, and achieve the teaching effect of combining theory with practice.

Second, the higher vocational "Mechanical Design" course teaching status analysis

"Mechanical Design" is a technical basic course connecting the preceding with the following in the basic course system of mechanical specialty in higher vocational colleges. At present, teachers emphasize discipline, systematicness and wholeness in course teaching, and adopt the traditional teaching method of teaching theory first and then teaching practice, which is completely out of touch with theory and practice. This paper analyzes the problems and reasons in traditional teaching.

(A) teachers have a weak concept of vocational education and weak engineering practice skills.

On the one hand, all teachers have received undergraduate or postgraduate education, and their ideas follow the general higher teaching mode, paying attention to the teaching of subject system and theoretical system, and emphasizing students' mastery and acceptance of knowledge. On the other hand, most teachers go to teaching posts directly after graduating from college, lacking enterprise work experience and practical engineering training, which cannot meet the needs of vocational education.

(B) the choice of course content is not conducive to the cultivation of students' ability

At present, the contents of some courses of mechanical design in higher vocational colleges have not fundamentally deviated from the characteristics of knowledge, pursuit of knowledge as a discipline and systematization, and deviated from the requirements of course knowledge serving vocational education goals. The author consulted the teaching syllabus of mechanical design in 20 higher vocational colleges in different regions through the national excellent course network, and found that the teaching content is basically the same and the knowledge range is wide. Some knowledge is rarely used or not used in engineering practice, and some knowledge is too deep for higher vocational students to accept, such as the calculation of fatigue strength and bending strength in gear transmission and the calculation and check of shaft strength.

(3) The traditional curriculum design mode has cultivated students' rigid thinking mode.

1. Most of the teachers in higher vocational colleges have received formal undergraduate education, and their teaching methods and means are branded as learning this course in universities, thus forming a traditional undergraduate teaching mode, that is, teachers use wall charts, models and blackboards to teach in class step by step according to the curriculum plan, including introduction, planar linkage mechanism, cam mechanism, belt drive and gear mechanism. Explain the theory from the aspects of composition, structure and working principle, show the model and homework, and finally design a course based on the model reducer (or other teaching models), and the whole course teaching is completed.

2. The course "Mechanical Design" in higher vocational colleges integrates mechanical principles, mechanical parts and other contents, and the course content is abstract and theoretical. However, the quality of students in higher vocational colleges is different from that in ordinary colleges, and many students have poor logical thinking ability, calculation ability and reasoning ability in using formulas and theorems. [2] In this way, there has been a teaching pattern in which the teacher's teaching plan is fixed, the method is rigid, and the students turn around the teacher's baton. As a result, teachers talk very hard, students study very hard, teachers complain that students are not serious, and students complain that teachers instill boring and useless things, forming a vicious circle between teachers and students.

(D) Teaching methods and means can not meet the needs of modern vocational and technical education.

At present, general vocational colleges still adopt the traditional teaching methods and means of writing on the blackboard, teachers giving lectures and students' homework. The hardware condition of my school is not bad, only multimedia courseware and model teaching are added. This greatly hinders the development of students' interest in learning and the guidance of thinking.

(E) The knowledge of the curriculum system is out of touch, which leads to poor learning effect of students.

"Mechanical Design" is a course in the technical basic course system of mechanical specialty. To learn this course well, students must have relevant knowledge of this course system, including mechanical drawing, tolerance and cooperation, metal materials, mechanical manufacturing and so on. However, the current situation is that students' preparatory knowledge is not solid and cross-knowledge cannot be used flexibly. Teachers often take superficial introduction to the cross-knowledge part, which makes students feel that their knowledge is out of touch, their thinking is incoherent, their understanding is not thorough and their learning effect is poor. Therefore, the author conducted a questionnaire survey on the learning effect after the end of the course. Among the 84 questionnaires, 68 people thought that the course didn't yield much, and some even described the learning experience as painful and uncomfortable.

(6) Traditional "model practice teaching" can't really cultivate students' perceptual knowledge.

At present, the practice of mechanical design course in higher vocational colleges is mainly based on "model practice teaching", that is, the parts observed by students are models, the disassembly mechanism is models, and the reducer for surveying and mapping is also models. The form of practical teaching mainly follows the centralized curriculum design of undergraduate course, and the curriculum design content of many schools adopts model reducer without exception. Due to the lack of practical engineering knowledge, the understanding of the function, structure, manufacture, assembly and use of reducer parts is only based on the model, which can only be imitated according to the model, compared with books and design manuals, resulting in the same curriculum design for a group or a class, which is nothing new. Moreover, due to the lack of knowledge in drawing, tolerance, materials and technology, even the basic projection and matching are full of mistakes reflected in the drawings, which can not achieve the actual teaching effect at all.

Third, the reconstruction and practice of the teaching mode of mechanical design course

In view of the problems existing in the above-mentioned teaching process, we have re-conceived the teaching reform from the following aspects, constructed a new teaching model and practiced it.

(A) change the concept of vocational teaching, strengthen the engineering skills training of teachers.

The concept change of vocational education is mainly the concept change of the teaching team with teachers as the main body, so well-known domestic vocational education experts and enterprise experts are specially invited to give special lectures. At the same time, teachers' engineering skills training should be actively strengthened, and teachers without enterprise experience should be required to go to enterprises to participate in engineering practice, so as to improve teachers' adaptability to vocational education.

(2) Focusing on the cultivation of ability and selecting teaching contents.

The selection of teaching content should be based on capacity building, which requires the change from focusing on professional subject system to focusing on practical teaching, and the teaching content should be adjusted and updated in time according to the development of the industry and the change of enterprise talent demand. To this end, we specially organized teachers to discuss the course content, combined with the local actual situation, deleted the course content involving principles, too abstruse theoretical derivation and formula proof content, and added practical teaching content, such as equipment observation and structure disassembly.

(3) Project teaching leads the curriculum development and forms a student-centered and teacher-led teaching model.

Project-based curriculum development has been applied and practiced in the curriculum reform of some schools. With the project as the carrier, the implementation of specific tasks and the cultivation of professional post ability have completely changed the traditional mode of knowledge transmission and student acceptance. In the past, the teaching methods of mechanical design were classroom teaching, demonstration and observation of mechanism and parts models, students' homework, and finally concentrated curriculum design. Now, we divide the whole course into four modules: common mechanism, common mechanical transmission, common mechanical parts and course design, and each module selects different projects according to the planned hours. For example, in the common mechanism module, it consists of a press motion mechanism, a sewing machine drive mechanism, an engine crank-connecting rod mechanism and an engine valve train. In the teaching process, we should follow the principle of taking professional activities as the guide, highlighting ability objectives, taking tasks as the main line, students as the main body and teachers as the leading factor, and create a strong practical engineering atmosphere in the whole course. We should follow the teaching process of task arrangement-on-the-spot observation-student discussion-scheme formulation-teacher-student interaction-teacher teaching-student practical operation-task completion, and truly form a student-centered and teacher-led teaching process.