Bostitch T55 manual Basic Tool Operation, Maintaining the Pneumatic Tool, Replacement Parts

BASIC TOOL OPERATION

Stanley-Bostitch pneumatic tools are cycled by a compressed air operated single piston design. The following illustrations show the four functional cycles that occur when the tool is operated to drive a fastener:

EXHAUST	FIG.1		FIG.2
OPEN	AT REST		DRIVING STROKE
PISTON		EXHAUST
STOP		SEALED BY
		PISTON STOP

HEAD VALVE CLOSED

HEAD VALVE OPEN

TRIGGER VALVE PORT

TRIGGER VALVE PORT

RESERVOIR

OF HIGH

(TO SUPPLY AIR TO TOP OF HEAD VALVE)

BLOCKED

PRESSURE

RESERVOIR OF

AIR

HIGH PRESSURE

AIR

HOLES IN

CYLINDER

WALL

RETURN

TRIGGER VALVE RELEASED

TRIGGER VALVE

CHAMBER

ACTUATED

BUMPER

PASSAGE FOR

AIR RELEASED FROM HEAD VALVE

AIR RELEASED

FROM ABOVE

HEAD VALVE

SLOTS FOR AIR FLOW

FOR PISTON RETURN

FIG.3

EXHAUST

FIG.4

OPEN

RETURNING

END OF STROKE

EXHAUST

TRIGGER STILL

STILL

PULLED

CLOSED

HEAD VALVE CLOSED

HEAD VALVE OPEN

AIR FLOWS

AIR IN

INTO

RETURN

RETURN

CHAMBER

CHAMBER

PUSHES

PISTON

UPWARD

TRIGGER VALVE

PISTON IS

TRIGGER VALVE

STILL ACTUATED

RELEASED –

SEALED

AIR PRESSURE RETURNS

AGAINST	TO TOP OF HEAD VALVE
BUMPER

MAINTAINING THE PNEUMATIC TOOL

When working on air tools, note the warnings in this manual and use extra care evaluating problem tools.

CAUTION: Pusher spring (constant force spring). Caution must be used when working with the spring assembly. The spring is wrapped around, but not attached to, a roller. If the spring is extended beyond its length, the end will come off the roller and the spring will roll up with a snap, with a chance of pinching your hand. Also the edges of the spring are very thin and could cut. Care must also be taken to insure no permanent kinks are put in the spring as this will reduce the springs force.

REPLACEMENT PARTS:

STANLEY-BOSTITCH replacement parts are recommended. Do not use modified parts or parts which will not give equivalent performance to the original equipment.

ASSEMBLY PROCEDURE FOR SEALS:

When repairing a tool, make sure the internal parts are clean and lubricated. Use Parker “O”-LUBE or equivalent on all “O”- rings. Coat each “O”-ring with “O”-LUBE before assembling. Use a small amount of oil on all moving surfaces and pivots. After reassembly add a few drops of STANLEY-BOSTITCH Air Tool Lubricant through the air line fitting before testing.

AIR SUPPLY-PRESSURE AND VOLUME:

Air volume is as important as air pressure. The air volume supplied to the tool may be inadequate because of undersize fittings and hoses, or from the effects of dirt and water in the system. Restricted air flow will prevent the tool from

receiving an adequate volume of air, even though the pressure reading is high. The results will be slow operation,

misfeeds or reduced driving power. Before evaluating tool problems for these symptoms, trace the air supply from the tool to the supply source for restrictive connectors, swivel fittings, low points containing water and anything else that would prevent full volume flow of air to the tool.

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