top of valve housing. The unit will immediately retract to the initial position, whereupon the unit will stop with all air to the unit shut off.
The needle type retract feed control valve regulates the flow of air from the piston, thus regulating the rate of retraction of the unit. The model 8670-( ) is furnished with a hydraulic check to control the rate of forward feed of the
SPECIAL NOTE: There are two needle valves (34617) contained in the valve block. One needle valve is for the retract feed control. The other needle valve [visible only after the removal of the name- plate (45184)) should not be adjusted or removed. If this needle valve should ever be removed, the correct assembled position is
The unit may be operated remotely thru the use of the start and retract signal ports located in top of the valve housing, using rec- ommended fittings, tubing and valves - see page 16.
The auxiliary supply port is pressurized whenever air is present at the air inlet of the tool.
The depth signal port is momentarily pressurized at the comple- tion of the forward feed stroke when the retract valve (44981) is actuated and can be used to activate a remote valve for the pur- pose of starting another tool or an accessory function.
M105
40
The tool retracted signal port is located in rear of piston rod
The valve section can be easily removed from tool for servicing and replaced with a spare unit, eliminating excessive
MOTOR AND GEARING SECTION
The motor and gearing section has been designed into a single unit that can be easily removed from tool and replaced with a spare unit while it is being serviced or repaired, eliminating exces- sive
HOUSING AND VALVE SECTION
The housing and valve section consists of a main housing, which houses the piston section and motor and gearing section, and the valve housing, which houses the retract valve that is actuated by the adjustment screw contained in the trip bracket. The retract valve components are accessible by removing striker plate (44987) from rear of valve housing. The piston and components are accessible by separating the main housing from the valve housing. See page 4 for disassembly procedure.
MOUNTING
The nose end of tool housing is provided with
as accessory items for tool mounting (see accessories section). The tool can be mounted in any position desired without impairing the function of the tool (see
SET-UP PROCEDURE
At the time the model 8670-( )
STROKE ADJUSTMENT
Determine the total stroke length the drill must travel to perform the drilling operation (see figure 1). Adjust the length of the stroke by loosening the two cap screws
FEED CONTROL VALVES
The models 8670-( ) are shipped from the factory with the retract feed regulating valve set at a fairly slow rate of feed. Turn valve counterclockwise to increase rate of feed. Turn valve clockwise to decrease rate of feed.
TIMING VALVES (59231 METERING NEEDLE)
The timing valve (59231 metering needle), located at the rear of the valve section, is used to regulate the time lapse between the time the drill bit has reached the
NOTE: A final adjustment of the adjusting screw
RETRACT VALVE
ADJUSTMENT SCREW
TOTAL STROKE LENGTH
3