附件243 中》 Problem7-13 7-14na hand-operated slide valve with H type neutral,the four valve openingsare i.e.xAt the left position of the valve:p connects with port A.and port b connects with port T.at the right position of the valve:p connects with B.A connects with T.How do the openings of the four valves change when the slide valve shifts from the neutral position to the left position or the right position? In addition,in engineering mechanical occasions,valves of this type are usually used to regulate speed. what is the operating principle and what kind of speed does it belong to? Problem7-14 Chapter 8 8-1 The figure shows the operating principle chart of a Zl5o loader hydraulic system.The actuators working characteristics of the loader are:1)flow rate conversion valve 4 ensures a constant flow rate q,to make the turning parts operate at a speed ranging from 600r/min to 1500r/min.q increases with n when n 1500r/min.Turning valve 6 is a hand-operated servo valve.Operating the turning hand wheel can open the valve which locates at the upstream of the tumning ylinder,the valve retums to its neutral position by mechanical feedback e the turing hand wheel is released.2)Boom ylinder and bucket cylinder can operate either individually or simultaneously,without the influence of the tuming actions. (1)Which speed control type does the turing cylinder belong to?What is the function of valve 5 here? (2)Which connection form does the multiple direction control valve belong to?How does it meet the equirements of the bucket cylinder and the boom cylinder? (3)How to regulate the speed of the bucke etcylinder and the boom eylinder? (4)What is the function of valve 10 in this system 附件 24.3 Problem 7-13 7-14 In a hand-operated slide valve with H type neutral configuration, the four valve openings are equal, i.e., x1=x2=x3=x4.At the left position of the valve: p connects with port A, and port b connects with port T; at the right position of the valve: p connects with B, A connects with T. How do the openings of the four valves change when the slide valve shifts from the neutral position to the left position or the right position? In addition, in engineering mechanical occasions, valves of this type are usually used to regulate speed, what is the operating principle and what kind of speed regulation circuit does it belong to? Problem 7-14 Chapter 8 8-1 The figure shows the operating principle chart of a ZL50 loader hydraulic system. The actuators include turning cylinders, bucket cylinders and boom cylinders. The power source is provided by a twin pumps and a single pump driven by a diesel engine, who’s working speed ranges from 600r/min to 2200r/min. The working characteristics of the loader are: 1) flow rate conversion valve 4 ensures a constant flow rate qz to make the turning parts operate at a speed ranging from 600r/min to 1500r/min. qz increases with n when n＞ 1500r／min. Turning valve 6 is a hand-operated servo valve. Operating the turning hand wheel can open the valve which locates at the upstream of the turning cylinder, the valve returns to its neutral position by mechanical feedback when the turning hand wheel is released. 2) Boom cylinder and bucket cylinder can operate either individually or simultaneously, without the influence of the turning actions. (1) Which speed control type does the turning cylinder belong to? What is the function of valve 5 here? (2) Which connection form does the multiple direction control valve belong to? How does it meet the requirements of the bucket cylinder and the boom cylinder? (3) How to regulate the speed of the bucket cylinder and the boom cylinder? (4) What is the function of valve 10 in this system?