Implement Control Valve Without a Line Relief Valve
Illustration 1
Typial Ty pial implement ontrol valve !ithout a line relief valve in the "#L$ position %1& Che' valve %2& (iston %)& Che' valve %4& *tem
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%+& *olenoi, %6& Che' valve for signal net!or' %-& Compensator spool %.& *ignal port %9& *olenoi,
The follo!ing implement iruits ,o not have line relief valves/ •
rtiulation
•
Centershift
•
Cirle ,rive
•
Wheel lean
Control stem %4& has metering holes an, slots that are ,esigne, to math the flo! reuirements for eah iruit If the omponents 3eome ,amage, or !orn the omponents in the ontrol valves are replaea3le Che' valve %1& an, he' valve %)& are inorporate, into the ontrol valve 3o,y gui,e, poppet is use, in or,er to re,ue lea'age The re,ution in lea'age re,ues ylin,er ,rift (iston %2& !ill shift !hen pressuri5e, oil is ,irete, to one si,e of the piston (iston %2& !ill unseat one of he' valves (ressuri5e, oil !ill open the other he' valve When the total flo! ,eman, eee,s the maimum pump flo! ompensator spool %-& ,istri3utes the hy,rauli pump flo! that is availa3le Compensator spool %-& reates an a,,itional restrition in eah iruit This is ,one so a single iruit annot use all of the availa3le pump flo! Compensator spool %-& maintains an eual pressure ,rop aross eah opening The oil flo! from eah implement ontrol valve is proportional to the opening of stem %4& Che' valve %6& allo!s pressuri5e, oil to travel out of the implement ontrol valve through a passage an, into the signal net!or' The he' valve also prevents 3a' pressure from the other ontrol valves from ating on the ontrol valve The highest loa, pressure is the only pressure that passes through the signal he' valve ll other signal he' valves !ill remain seate, The signal oil also 3eomes the input signal to the 3a' of ompensator spool %-& The signal oil enters through port %.& *ignal oil plus the fore of the spring at on ompensator spool %-&
Compensator spool %-& regulates the flo! of oil to the ylin,er s !hen multiple implement iruits are 3eing use, *olenoi, %+& an, solenoi, %9& !or' in,epen,ently of eah other in or,er to shift ontrol stem %4& When the operator moves the 7oysti' an eletrial signal !ill ause one solenoi, to energi5e The energi5e, solenoi, !ill ,iret pilot oil to the en, of ontrol stem %4& The ,e8energi5e, solenoi, !ill have a passage open to the hy,rauli tan' The pilot oil on one si,e of ontrol stem %4& !ill shift ontrol stem %4& against the spring on the opposite si,e *olenoi, %+& an, solenoi, %9& are varia3le
Illustration 2
Typial implement ontrol valve !ithout a line relief valve in operation
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%1& Che' valve %2& (iston %)& Che' valve %4& *tem %+& *olenoi, %6& Che' valve for signal net!or' %-& Compensator spool %.& *ignal port %9& *olenoi,
When the operator moves the 7oysti' an eletrial signal !ill ause one solenoi, to energi5e When solenoi, %+& is energi5e, solenoi, %+& !ill ,iret pilot oil to the en, of ontrol stem %4& When solenoi, %9& is ,e8energi5e, solenoi, %9& !ill have a passage open to the hy,rauli tan' The pilot oil on one si,e of the ontrol stem %4& !ill shift ontrol stem %4& (ump supply oil !ill flo! into the internal passages of the ontrol valve (ump supply oil !ill flo! past ompensator spool %-& an, shift piston %2& to the left (iston %2& !ill unseat he' valve %1& (ump supply oil !ill flo! past he' valve %)& to the ylin,er The opposite en, of the ylin,er !ill 3e open to the hy,rauli tan' 3y he' valve %1& (ump supply oil !ill also unseat he' valve %6& The oil that flo!s past he' valve %6& !ill flo! into the signal net!or' The signal net!or' !ill sen, pilot oil to the implement piston pump in or,er to upstro'e the pump The implement piston pump !ill maintain oil flo! in or,er to meet the system ,eman,s Implement Control Valve With a Line Relief Valve
Illustration )
%1& Che' valve %2& (iston %)& Che' valve %4& *tem %+& *olenoi, %6& Che' valve for signal net!or' %-& Compensator spool %.& *ignal port %9& *olenoi,
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The follo!ing implement iruits inlu,e one line relief valve/ •
la,e lift
•
la,e tip
•
la,e si,eshift
•
Ripper
•
*arifier
•
*no! plo!:,o5er lift
•
*no! plo!:,o5er angle
The follo!ing implement iruits inlu,e t!o line relief valves/ •
*no! !ing lift
•
*no! !ing tilt
Che' valve %)& ontains a he' valve an, a relief valve The relief valve protets the ro, en, of the iruit from high pressures If the pressure in the ro, en, of the iruit rises a3ove the setting of the relief valve the relief valve !ill open The relief valve !ill ,rain the eessive pressure to the hy,rauli tan' Implement Control Valves !ith la,e ;loat
Illustration 4
%1& Che' valve %2& (istons %)& Che' valve %4& *tem %+& *olenoi, %6& Che' valve for signal net!or' %-& Compensator spool %.& *ignal port
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%9& *olenoi, %10& #rifie %11& #rifie
The follo!ing implement valves have a 3la,e float funtion/ •
la,e lift
•
*no! plo!:,o5er lift
*olenoi, %9& is energi5e, to the maimum of one amp in the float position The solenoi, ,irets pilot oil to the 3a' of stem %4& (ilot oil shifts stem %4& all the !ay to the left #rifie %11& meters pressuri5e, oil from the pump supply port into the internal passages of the ontrol valve (ressuri5e, oil flo!s through the internal passages in the ontrol valve to pistons %2& (ressuri5e, oil moves pistons %2& out!ar, (istons %2& push he' valve %1& an, he' valve %)& open #rifie %10& an, orifie %11& are ,ifferent si5es #rifie %10& is smaller #rifie %10& !ill meter a small amount of pressuri5e, oil to the hy,rauli tan' in or,er to limit the pressure of the oil insi,e the ontrol valve #rifie %10& maintains the pressure insi,e the ontrol valve in or,er to 'eep pistons %2& shifte, out!ar, In the float position 3oth ylin,er ports are vente, to the hy,rauli tan' Control Valve #peration
Illustration +
la,e ontrol valve in the L#W
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%.& *ignal port %9& *olenoi,
When the operator moves the 7oysti' an eletrial signal !ill ause one solenoi, to energi5e *olenoi, %9& is energi5e, in the L#W
