| 摘要 |
#CMT# #/CMT# The device has a tensioning pulley (7) loosely mounted in rotation around a vertical axis (Z2) at an end of a tensioner arm (2). A compression spring (21) solicits the arm in pivoting around another vertical axis (Z1). A blocking and unblocking unit blocks and unblocks movement of the arm with respect to a plate (1) according to operation speed of an engine. The unit is constituted by a cam (3), another compression spring (8), ball bearings (4a, 4b), a slanting bearing (4c), a double rowed ball bearing (11), a ring (10), a platform body (12) e.g. machined washer, a lever (5) and a mass (6). #CMT#USE : #/CMT# Device e.g. automatic tensioning pulley, for automatically tensioning a belt of an engine e.g. petrol engine, of a motor vehicle e.g. automobile, for a power train. #CMT#ADVANTAGE : #/CMT# The device improves the prohibition of the movement of the tensioner arm during the start-up phase of the engine. The device preserves the path length equal to the length of the belt, thus reducing the beats of strand during the start-up of the engine, during operation phase of the engine at low-power and at heavy load or during high brutal decelerations of the engine, and hence allowing the device to avoid the radial runout of the belt at the start-up, and avoiding the usage of additional components of accessory surface such as one-way clutch. #CMT#DESCRIPTION OF DRAWINGS : #/CMT# The drawing shows a sectional view of a belt tensioning device for an engine of a motor vehicle in a blocked mode. Z1, Z2 : Vertical axes 1 : Plate 2 : Tensioner arm 3 : Cam 4a, 4b : Ball bearings 4c : Slanting bearing 5 : Lever 6 : Mass 7 : Tensioning pulley 8, 21 : Compression springs 10 : Ring 11 : Double rowed ball bearing 12 : Platform body. |
