2519 Dana Drive, Laurinburg, NC 28352 USA · Telephone: 910-276-4853
Toll Free: 1-800-782-3379 | Fax: 910-276-1354
info@rostratransmission.com · www.rostratransmission.com

Solenoid Construction

1. The Coil holds the magnet wire and converts electricity into magnetic energy. The Can holds parts together, is part of the magnetic circuit, and directs the magnetic flux. The Stop locates the spring and stops armature movement. The Armature is the moving part in solenoid that clicks. The Seat opens and closes to control the flow of fluid. The Port mates to the transmission VB.

2. Here are some important terms. Stroke is the amount of distance armature moves in the pace between armature and stop.

3. Voltage, also known as electromotive force (EMF) is the force that pushes the electricity through the conductor. Its electrical symbol is E. Compared to a hydraulic circuit, voltage is similar to the force of a plunger acting on the fluid. The spring force pushing on a spool valve generates a hydraulic pressure.

Current is the amount of electricity flowing through the conductor. Its electrical symbol is I, and is measured in Amps. In a hydraulic circuit, the current would be similar to the flow rate of the oil in a circuit.

Resistance, measured in ohms, is the opposition to the flow of electricity. In a hydraulic circuit, resistance can be thought of as a flow restriction, such as an orifice.

4. Hydraulic Function On/ Off solenoid is typical for a shift solenoid. This solenoid is normally closed. With the solenoid seat closed to oil flow, pressure builds up against the spool and keeps it in a downward position. Oil flows through the spool to exhaust. When turned on, the solenoid seat opens, allowing oil to exhaust. The spring pushes the spool, redirecting the flow of oil to the proper clutch.

Click on an illustration to see an enlargement.

Other related articles: