Fastening tool having improved pressure regulator device
AssigneeThe Stanley Works
InventorMark F. Braunlich
Life of this patent
Estimating the term…
Abstract
An air tool for setting fasteners includes a pressure selecting valve member and internal passages for air balancing this valve member with a pressure relief pilot valve for bleeding a chamber of the valve member to atmosphere responsive to increased motor operating pressure. A plurality of such pilot valves may be provided in a manually rotatable selector disc. Each pilot valve may be set to a different torque output for quick and easy tool adjustment upon registering a given pilot valve with the pressure selecting valve chamber upon manipulation of the selector disc.
Claims13
An air operated fastener setting tool comprising
- an air motor,
- a housing for the motor, the housing having a passageway for supplying air under pressure to the motor,
- an on-off control mounted in the housing for establishing open and closed air flow conditions in the passageway,
- a pressure regulator mounted in the housing between the on-off control and the motor, the pressure regulator including
- a valve chamber having an inlet port and an outlet port, the on-off control and the motor communicating through the passageway respectively with the inlet and outlet ports,
- a pressure selecting valve member reciprocable in the chamber between a relatively open position and a relatively restricted position,
- a spring mounted in the chamber biasing the pressure selecting valve member toward open position, and
- passage means for directing air pressure on the motor side of the pressure selecting valve member against its opposite ends such that it is initially air balanced and biased by the spring into open position upon the on-off control establishing the open air flow condition, and
- a pressure relief pilot valve mounted in the housing for connecting the chamber with atmosphere and creating a pressure differential between opposite ends of the pressure selecting valve member for moving it toward restricted position responsive to increased motor operating pressure to restrict the outlet port and reduce air pressure on the motor side of the regulator whereby, when the motor operating pressure increases as load is applied to the motor output, the pressure selecting valve member is automatically positioned in a force balanced condition within the chamber for motor pressure regulation throughout a range of running conditions from free running speed to stall at a specified mean torque motor output, further including a plurality of pressure relief pilot valves mounted in the housing for connecting the chamber with atmosphere, each of the pilot valves being adjusted to a different specified tool output torque, and a manually operable selector mounted within the housing and having a passage for selectively registering the chamber with any one of the pressure relief pilot valves for connecting the chamber with atmosphere and quickly establishing a previously adjusted specified tool output torque.
In an air operated fastener setting tool having an air motor, a housing for the motor, the housing having a passageway for supplying air under pressure to the motor, and a pressure regulator mounted in the housing, the pressure regulator including a valve chamber having an inlet port and an outlet port connected to the passageway with a pressure selecting valve member movable in the chamber between a relatively open position and a relatively restricted position respectively establishing relatively open flow and restricted flow conditions in the chamber between said ports, a spring biasing the pressure selecting valve member toward its open position, and passage means for directing air pressure on the motor side of the pressure selecting valve member against its opposite ends such that it is initially air balanced and biased by the spring toward open position, a selectable set torque device comprising
- a plurality of pressure relief pilot valves in the housing for connecting the chamber with atmosphere, each of the pilot valves being adjusted to a different specified tool output torque, and
- a manually operable selector mounted within the housing and having a passage in communication with the chamber, the passage being selectively registrable with any one of the pressure relief pilot valves for connecting the chamber with atmosphere and quickly establishing a previously adjusted specified tool output torque.
Dependencies are inferred from the claim text.