초록 ▼

The air tool of the present invention includes a torque shut-off valve totally enclosed within and substantially coaxial with the body housing of the tool. The torque shut-off valve includes a valve member reciprocally sliding in and guided by a bore and counterbore in the valve body. The valve memb

The air tool of the present invention includes a torque shut-off valve totally enclosed within and substantially coaxial with the body housing of the tool. The torque shut-off valve includes a valve member reciprocally sliding in and guided by a bore and counterbore in the valve body. The valve member is biased by a reset spring to its open position before the tool cycle is initiated. In operation, the valve member is axially biased toward its open position by supply line air pressure in an air inlet chamber in conjunction with controlled reduced air pressure in an associated compartment and is axially biased toward the closed position by motor inlet pressure. A preselected motor back pressure resulting from achieving the desired tool torque operates to overcome the opposing pressure to close the valve member to block air flow to the motor.

대표청구항 ▼

An air tool comprising a body housing, an air motor in the body housing, an air line in the body housing selectively to supply compressed inlet air to the motor and a torque shut-off valve coaxially contained totally within the body housing in the air line upstream of the air motor, the torque shut-

An air tool comprising a body housing, an air motor in the body housing, an air line in the body housing selectively to supply compressed inlet air to the motor and a torque shut-off valve coaxially contained totally within the body housing in the air line upstream of the air motor, the torque shut-off valve comprising (a) a valve body having a bore and counterbore along its longitudinal axis and having an air inlet passage to the motor extending from the bore radially around the counterbore, (b) a valve member having opposed upstream and downstream sides reciprocally slidable in the bore and counterbore between an open position allowing air to pass from the bore through the air inlet passage to the motor and a closed position blocking flow through the air inlet passage when the tool has reached a preselected torque, and (c) air pressure control means for controlling pressure of the inlet air acting on the upstream side of the valve member, the valve member only being subjected to axially applied air pressure loads with the controlled pressure inlet air acting on the upstream side of the valve member and the motor back pressure acting on the downstream side of the valve member.