外文资料In recent years, the hydraulic motor with brachytely and big torsional moment has great changes, the new structure continuously appears. But, all these hydraulic motors can be divided into two broad categories of single and multi-role according to the role of the number of plunger in each turn. The motors also can be divided into radial and horizontal direction according to the arrangement of the plunger. And the radial motors can be divided into different types according to structure and the summon power way of the plunger.No matter single and multi-role, the plug-hole of radial-piston hydraulic motor is equated by circle, arrayed radial. The plunger displaced by the impulse of pressure oil, then the volume of the cylinder changed, the summon power formed the rotation of the motor, all of these above are the mechanism of action of the motors.The rotor of the single role hydraulic motor has a circle of rotation, each plunger worker once reciprocation. The principal axis is eccentric axis in all the radial-piston hydraulic motors. The multi-role hydraulic motor had a guide rail curve, whose numbers are the action times. The rotor had a circle of rotation, the plunger worker many times reciprocal at the same time. The radial motors can be divided into several categories of plunger, ball blocker, blade.The structure of the single-role motors is simpler, the machine element number of it is less, the technology is better, and the cost is less. But the structure dimension of the single-role motor is longer than the multi-role motor in the same displacement each turn (or output torsional moment), and the single-role motor also have fluctuation of the output torsional moment and rotary speed.The homonymyhigh-pressure column tune of the single-role motor had major radial unbalance force that causes the brachytely stabilization of the motor became worse. Only increasing the capacity of the bearing, it can meet the requirements of the operating life of the bearing at the same time.Generally speaking, the speed of single-role motors is higher than the multi-role in the same displacement because of the work feature of the single-role motors. The structure of the multi-role motors is complicated than single-role, the number of machine element is bigger as well. Some machine element needs some special equipment to process them. The heat treatment of the guide rail is more difficult. And the selection of the texture parameters in design is more difficult and harder. The cost is higher without a doubt.But the multi-role motor output larger torsional moment and had lighter weight of unit power in the same working pressure. The radial force of hydraulic motor can completely equilibrate and had higher started torsional moment efficiency as long as selecting the suitable plunger number and action number. In abstract the pulsation work of output torsional moment would be zero if one select guide rail curve reasonable and assign argument to the principle of non-pulsation in design. All of these can made it’s low speed stab ility better.People manufactured many new types of hydraulic motor in recent years. The structure of old motor refreshes and develops continuously. The motor’s life and performance are raised but the cost is dropped as well. Various kinds of brachytely big torque hydraulic motors utilized more than 60 main frame extensively because theirstrong competitive ability.Multi-role within the curve of the radial piston hydraulic motor is divided into transmission plunger, beam transmission, wheel transmission .The most used are Beam transmission and Wheel Transmission motor .the france Crane Park motor produces the most ,the Rated working pressure is 30 MPa in all the Low Speed and High Torque motors Crane Park motor has the highest working pressure Recently , end assignment wheel motors is developed ,and the function was greatly improved . In recent years, Accompanied by Ball Cypriot Vice static and dynamic pressure bearing theory developed, Multi-role Radial ball plug Hydraulic Motor Developed quickly , such as Japan’s HMA series . Which are widely used in engineering and architecture. The hydraulic motor with brachytely and big torsional moment , commonly can be designed into Rotating shell or Axis rotation ,they are named shellmotor . shell motor that build in the Wheel rim is called Wheel motor ,which direct drive the wheels ,can replace the gear drive and make up the Hydraulic drive axle .In the 1970s , engineering Machine ,architecture Machine, mine Machine and Watercraft Deck Machine etc all use sap pressure technology .The element that advance the hydraulic motor with brachytely and big torsional moment has sharply increased to 40s . Variety species and main engine application has developedgreatly .but most for the main engine factory. Because losing the main knowledge of kinematic pair .The using were still remain in mapping ,imitation and Experience in analog design manufacture were still in Groping .so although we have many Developers ,there are still no one hydraulic motor passed the appraisement . the hydraulic motor with brachytely and big torsional moment .However，Imitation and digestion of foreign products, can provides us a useful design and manufacturing experience. From 1974, Multi-role inner curve oil hydraulic motor Spot Turn NJM and Cranked shell model NKM etc were worked out and designed .There are some species in Spot Turn series , after experience according to JB 2148-77 standard and pass the qualification ,we can produce in quantity in fixed-point .In NJM hydraulic motor, guide rail is Sectional Type , according to discharge capacity, the succession has 16 discharge capacity species .this kind of motor has a good efficiency ,and the experiencing duration of life has exceeded 5000h.中文译文近年来，低速大扭矩液压马达有了较大的发展，新结构不断出现。