机械-手臂可调式捆包打结器-毕业论文

1Bale twine knotter with adjustable wiperBackground of the inventionThis invention relates to twine knotters for hay or straw baling machines and more particularly to an improved wiper arm for such knotters.In one conventional baler, the twine knotter includes a rotatably mounted billhook for forming a loop of twine thereabout. On one side of the billhook is a wiper arm which has a pair of finers defining a fork for receiving and guiding twine used to tie a bale. On one side of the billhook is a knife riveted to the fork for cutting the twine after a loop in the twine has been formed around the billhook. A wiper is formed integrally with the fork of the arm and strips or wipers the loop of twine form around the billhook as the severed end of the twine is held in the billhook jaw. Proper adjustment of the wiper arm relative to the billhook is critical to the operation of the nkotter as the wiper must strip or wipe the twine loop from the billhook to complete the formation of the knot. Wiper arm adjustment is performed initially at the point of manufacture and periodically thereafter when servicing the baler. It is accomplished by modeling or bending the arm in three areas with a special tool. By modeling, the wiper is centered with respect to the heel of the billhook and adjusted so theat it just clears the billhook jaw. For this reason, it is desirable that the wiper arm be relatively rigid and unyielding so that proper adjustment can be maintained and yet be sufficiently bendable to permit initial adjustmen. Also, in recent years , stronger twines are being used on such balers to tie bales of higher density. Such changes subject the wiper arm to higher forces during op...