CAD as a computer technology under the progress of the auxiliary drawing products, for the mechanical fixture design has brought convenience. CAD greatly improve the efficiency of design, and more beautiful and accurate, according to the design of the finished product has a higher quality of course. This paper will discuss the mechanical fixture design based on CAD.

Portable electronic products are playing an increasingly important role in people’s lives, but the continuous power supply problem outdoors has increasingly become the bottleneck for its development, moreover, it also often makes people not get a good experience due to inadequate power. In allusion to the above problems, one kind of limb movement power generation device was designed. This device is composed of crank and connecting rod mechanism, speed-increasing gear set micro-generator and so on, and it converts the kinetic energy of human movement into electrical energy, stores electrical energy to storage battery or directly supplies for electronic products, in order to solve the continuous power supply problem outdoors for portable electronic products, active exploration has been made.

This article analyzes the self-priming performance of hydraulic pumps in hydraulic systemsanddescribes many factors affecting the poor self-priming performance of hydraulic pumps in hydraulic systems.All these factors are analyzed one by one and some effective solutions are proposed.

A fault diagnosis algorithm of gear pump based on sparse representation is proposed in this study. The vibration signals of the faulty gear pumps are different from those of the normal ones. Therefore, by comparing the vibration signal of an unknown gear pump with the training signals form the normal gear pumps, its fault can be analysed and identified. The sparse representation is used in this study and the vibration signal of the test sample is linearly represented based on the dictionary formed by the normal signals. When the reconstruction error is large enough, the present gear pump is judged to be faulty. Otherwise, it is a normal one. Experiments are conducted based on some measured vibrations signals from both faulty and normal gear pumps. The results show the effectiveness of the proposed method.

In this paper, combined with the working requirements of throttling speed regulation in the circuit, the structure principle and working characteristics of speed control valve in flow control valve are analyzed, the speed regulating performance and characteristics of speed regulating valve in hydraulic system are expounded, It is pointed out that the relationship between speed and load of speed regulating valve is rigid in the process of speed regulating of hydraulic system, that is to say, the speed regulating valve is suitable to be used in the case of large load variation, high speed stability requirements of the occasion.