Device for automatically adjusting tension of endless running member in wrapping connector driving

In a wrapping connector driving apparatus including an endless running member reeved around two rotatable shafts spaced apart by a specified distance, tensioning means disposed on the slack side of the running member for imparting tension to the running member by a tightener, and a transmission case housing the endless running member therein and containing at its lower portion oil so that the oil is entrained by the endless running member, a device for automatically adjusting the tension on the endless running member characterized by:

• a main body of the adjusting device being attached to the transmission case and having at its upper portion an oil well for accommodating the oil entrained by the endless running member,
• the adjusting device main body being internally formed with a cylinder portion and having a piston slidably inserted in the cylinder portion and a resilient member causing the piston to press the tightener against the endless running member,
• the adjusting device main body being formed with an oil supply channel for supplying the oil from the oil well to the cylinder portion through a check valve and with an oil escape passageway for permitting the cylinder portion to communicate with the oil well and releasing the internal high pressure of the cylinder portion resulting from impact on the piston,
• the oil supply channel having a starting end in communication with a bottom portion of the oil well, the oil escape passageway having a terminal end in communication with a bottom portion of the oil well, the supply channel starting end being in communication with the oil well at a higher level than the escape passageway terminal end,
• the adjusting device main body being attached to the transmission case by bolts positioned at least above and below the cylinder portion toward the endless running member, the oil well being positioned at a larger distance away from the endless running member than the upper and lower attaching bolts.