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| Valve Body: Valves |
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©Copyright 2008-09 ®All Rights Reserved Disclaimer Privacy Policy
©Copyright 2008-09 ®All Rights Reserved Disclaimer Privacy Policy
At the heart of the automatic transmissions hydraulic control system is the
valve body. It usually consists of three parts: the separator plate, the transfer
plate and the valve body itself. These three parts are installed on the
transmission as a single unit. It will be constructed of either iron or aluminum.
Inside the valve body you will find three different types of valves: the poppet,
the check ball, and the spool valve.
The poppet valve can be a ball or a flat disc and usually has a stem that acts
as a guide for the valves opening or closing. This valve like so many others
acts as a port to either block or allow the flow of fluid.
A check ball valve sits in a seat in the valve body that allows or blocks fluid
according to the direction of its flow. These check balls can be either normally
open or closed depending on the application and manufacturer.
The spool valve is by far the most common valve found in automatic
transmissions. They resemble a spool of thread with large areas used to block
fluid flow called lands and stemmed areas called valleys. At each end of the
valve is located a reaction area. This is the area where fluid pressure, linkage,
or a spring acts as a force to activate the valve.
valve body. It usually consists of three parts: the separator plate, the transfer
plate and the valve body itself. These three parts are installed on the
transmission as a single unit. It will be constructed of either iron or aluminum.
Inside the valve body you will find three different types of valves: the poppet,
the check ball, and the spool valve.
The poppet valve can be a ball or a flat disc and usually has a stem that acts
as a guide for the valves opening or closing. This valve like so many others
acts as a port to either block or allow the flow of fluid.
A check ball valve sits in a seat in the valve body that allows or blocks fluid
according to the direction of its flow. These check balls can be either normally
open or closed depending on the application and manufacturer.
The spool valve is by far the most common valve found in automatic
transmissions. They resemble a spool of thread with large areas used to block
fluid flow called lands and stemmed areas called valleys. At each end of the
valve is located a reaction area. This is the area where fluid pressure, linkage,
or a spring acts as a force to activate the valve.