There are provided: an on-off valve (7) which opens/closes flow between a first port (P) where compressed air is supplied and a second port (A) connected to an outside; and a delay mechanism (8) which opens the on-off valve (7) after a predetermined period of time has elapsed. The delay mechanism (8) includes: a throttle valve (22) communicatively connected to the first port (P); a piston (36) connected to the on-off valve (7); a pressurizing chamber (40) communicatively connected to a pressure-receiving surface (37) of the piston (36); and a communicating passage (42) communicatively connecting a throttle passage (28) of the throttle valve (22) to the pressurizing chamber (40). When a pressure of the compressed air supplied from the first port (P) to the pressurizing chamber (40) through the throttle passage (28) and the communicating passage (42) reaches a set pressure, a valve opening force exerted on the piston (36) exceeds a valve closing force exerted on the on-off valve (7), and thereby the on-off valve (7) is opened. Thus, the compressed air from the first port (P) is supplied to the outside through the second port (A).

A time-out indicator is adapted for use in a pneumatic strapping tool for tensioning a strap around a load, adhering the strap onto itself, and cutting a feed end of the strap. The strapping tool has a cylinder housing, a piston disposed within a cylinder in the cylinder housing, a pneumatic weld motor operably connected to the piston, a vibrating weld element operably connected to the piston for contacting the strap and adhering the strap onto itself. A pneumatic module is mounted to the cylinder housing to provide compressed gas to the cylinder housing and the pneumatic weld motor. The time-out indicator includes a sleeve fitted into an opening in the module. The opening is disposed above and in communication with the cylinder. The sleeve defines a central, longitudinal opening. An indicator is biasedly mounted in the sleeve and disposed for contact with the piston. The indicator reciprocates between a retracted position and an extended position and indicates a cycle of the strapping tool as an in-cycle state in which the cylinder is under pressure, pressurizing the piston to urge the weld element into contact with the strap and a timed-out state in which the piston is not pressurized.

The connector comprises a manual ring actuator (86) operatively connected to a valve (34) so as to permit air to be conducted to a fastener driving tool (24) when the actuator is moved to an extreme position. When the tool is activated and its nosepiece engaged with a substrate, it will be enabled and it can be fired. Exhaust generated from each firing operation maintains a piston (52) of the valve (34) at the desired position so as to permit the air to reach the tool. If it is not fired for a predetermined period of time the valve (34) is moved, under the influence of a spring (62) or a pneumatic-biasing force, to a position which disables the tool. Enablement of the tool is only again achieved by moving the actuator (86) to the extreme position. The disabling of the tool prevents the inadvertent or accidental firing of the tool.

The invention provides for a a fluid operated timer comprising an input for the fluid, reservoir means for receiving fluid from the input, actuator means responsive to the fluid pressure in the reservoir means reaching a threshold value, wherein the reservoir means comprises a plurality of reservoirs and the timer further comprises means for selectively controlling operative connection of at least one of the plurality of reservoirs to the input so that the volume of the reservoir means presented to the input fluid can be selectively varied.

The invention provides for a a fluid operated timer comprising an input for the fluid, reservoir means for receiving fluid from the input, actuator means responsive to the fluid pressure in the reservoir means reaching a threshold value, wherein the reservoir means comprises a plurality of reservoirs and the timer further comprises means for selectively controlling operative connection of at least one of the plurality of reservoirs to the input so that the volume of the reservoir means presented to the input fluid can be selectively varied.

A pneumatic circuit prolongs a pneumatic valve (20) opening time using an accumulator with two quick exhaust type valves (36, 46) in series while providing a rapid valve closing time. This structure and method is self-contained and amenable to retrofit in existing installations without any external connections. Slow opening is achieved by routing inlet gas pressure simultaneously to an accumulator (51) and the operating cylinder (21) of the valve to be opened. A tortuous piping path (61, 36, 62, 63, 44, 46) and increased volume to be pressurized due to the addition of the accumulator (51) substantially reduces the isolation valve opening time, thereby eliminating problems associated with quick opening of a pneumatic valve.

When the pneumatic valve (20) needs to be closed quickly, slight venting toward the inlet valve (29) immediately causes the quick exhaust valves (36, 46) to vent (39, 49) their downstream pressure. The accumulator (51) then vents through its quick exhaust valve (46) while separately the main quick exhaust valve (36) quickly vents the air cylinder (21) of the pneumatic valve. Closing times penalties of less than 50 milliseconds can be achieved using this configuration and opening times can be increased by adjusting the volume of the accumulator.