Tham khảo tài liệu 'mechanical movement 2', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 8 Mechanical Movements. . X gm c ịpỳ ằ J 10 L Mechanical Movements. 9 I. Illustrates the transmission of power by up the slack the belt transmits motion from one of the larger pulleys to the other but simple pulleys and an open belt. In this case both of the pulleys rotate in the same direction. 2. Differs from I in the substitution of a . crossed belt for the open one. In this case the direction of rotation of the pulleys is reversed. By arranging three pulleys side by side upon the shaft to be driven the middle one fast and the other two loose upon it and using both an open and a crossed belt the direction of the said shaft is enabled to be reversed without stopping or reversing the driver. One belt will always run on the fast pulley and the other on one of the loose pulleys. The shaft will be driven in one direction or the other according as the open or crossed belt is on the fast pulley. 3. A method of transmitting motion from a shaft at right angles to another by means of guide-pulleys. There are two of these pulleys side by side one for each leaf of the belt. 4. A method of transmitting motion from a shaft at right angles to another whose axis is in the same plane. This is shown with a crossed belt. An open belt may be used but the crossed one is preferable as it gives more surface of contact. 5. Resembles I with the addition of a movable tightening pulley B. When this pulley is pressed against the band to take i when it is not the belt is so slack as not to transmit motion. 6. By giving a vibratory motion to the lever secured to the semi-circular segment the belt attached to the said segment imparts a reciprocating rotary motion to the two pulleys below. 7. A method of engaging disengaging and reversing the upright shaft at the left. The belt is shown on the middle one of the three pulleys on the lower shafts a which pulley is loose and consequently no movement is communicated to the said shafts. When the belt is traversed on the left-hand pulley which is .
