Patent ID: 8108101

Claim:
A traveling speed reduction gear lubricating oil cooling device in a work vehicle, including: a tubular wheel mounting sleeve that rotates as one with wheels of the work vehicle; a traveling motor used to drive said wheel mounting sleeve; a reduction gear unit housed inside said wheel mounting sleeve and constituted with a gear mechanism that slows the rotation of said traveling motor and transmits the slowed rotation to said wheel mounting sleeve; and a circulation path and a lubricating oil pump disposed outside said wheel mounting sleeve, via which reduction gear lubricating oil drawn out of said wheel mounting sleeve is cooled at an oil cooler and then made to travel back into said wheel mounting sleeve: characterized in that said traveling speed reduction gear lubricating oil cooling device comprises: a speed sensor that detects said speed of said traveling motor; a reference speed setting means for setting in advance a reference speed Vh at which said lubricating oil pump is stopped in order to prevent air intake at said lubricating oil pump during normal operation and a startup operation reference speed Vc, lower than said reference speed Vh, at which said lubricating oil pump is stopped in order to prevent air intake at said lubricating oil pump during startup operation; a speed comparison means for comparing said speed V detected by said speed sensor with a startup operation reference speed Vc set for said traveling motor; and a startup operation control means for engaging a drive motor for said lubricating oil pump at a speed lower than a normal operation speed if the detected speed V is lower than said startup operation reference speed Vc and stopping said drive motor for said lubricating oil pump if the detected speed V is higher than said startup operation reference speed Vc.