Patent ID: 8678340

Claim:
A hydraulic control valve apparatus for an automatic transmission in a vehicle, the hydraulic control valve apparatus comprising: a valve body that is formed with a hydraulic circuit for a pressurized oil and disposed in the vehicle in a horizontal direction; and a hydraulic control valve that is disposed in the valve body in parallel to an upper horizontal surface of the valve body, the hydraulic control valve including a spool, a biasing member that biases the spool, a damper chamber that accommodates the biasing member, a housing in which the spool is accommodated and slidably guided, and a drain port formed in the housing so as to discharge the pressurized oil, wherein the valve body includes a drain hole through which the pressurized oil is discharged from the hydraulic control valve, and a first communication passage that supplies the discharged oil from the drain hole of the valve body to the damper chamber of the hydraulic control valve, and the drain hole and the first communication passage are formed on the upper horizontal surface of the valve body, wherein the first communication passage allows fluid communication between the drain port of the hydraulic control valve and the damper chamber of the hydraulic control valve through the drain hole of the valve body, and wherein the first communication passage is in the form of a horizontally extending groove that is open to the upper horizontal surface of the valve body.