초록 ▼

The invention provides a low pressure shut off device contained within a pneumatic tool that senses the air pressure of an air stream supplied to a pneumatic motor and shuts off the air flow when the pressure falls below a predetermined level set to maintain consistent performance of the tool and to

The invention provides a low pressure shut off device contained within a pneumatic tool that senses the air pressure of an air stream supplied to a pneumatic motor and shuts off the air flow when the pressure falls below a predetermined level set to maintain consistent performance of the tool and to avoid damage to the tool or to the workpiece. The invention includes a throttle valve, a throttle piston that moves to open and close the valve, and a device for sensing the air pressure of the supply stream, holding the throttle valve open when the pressure is sufficient and closing it when the supply pressure is insufficient. The invention may also be used in combination with an air control system within a pneumatic tool such that the sensing device shuts off the flow of air to the air control system as well as the motor when the air control system pressure is insufficient.

대표청구항 ▼

An apparatus for shutting off an air supply to a pneumatic motor when the supply air pressure drops below a desired level, the apparatus comprising: a main air passageway for conducting pressurized air from an external source to the pneumatic motor; a throttle valve located in said passageway for co

An apparatus for shutting off an air supply to a pneumatic motor when the supply air pressure drops below a desired level, the apparatus comprising: a main air passageway for conducting pressurized air from an external source to the pneumatic motor; a throttle valve located in said passageway for controlling the flow of air to the pneumatic motor, said throttle valve having an open and a closed position; a piston chamber; a throttle piston in said piston chamber which controls said throttle valve and said piston being movable between a closed position in which said throttle valve is closed and an open position in which said throttle valve is open; spring means for biasing the throttle piston to the closed position; latching means for holding the throttle piston in the open position against the bias of said spring means; sensing means for sensing a drop in the air pressure introduced into said main air passageway; and said sensing means being attached to said latching means such that when the supply air pressure drops below a desired level said sensing means causes said latching means to release said throttle piston and allow said spring means to move said throttle piston to the closed position thereby closing said throttle valve to the flow of air.