hydraulic torque converter
Quick Summary
A hydraulic torque converter is a device that uses a liquid, typically oil, to transmit and modify rotary motion and torque. It is a type of hydrokinetic hydraulic power transmission system.1
Similar to a hydraulic coupling, it features an impeller on the drive shaft and a runner on the driven shaft, both within a liquid-filled casing. The key difference is the addition of a stationary, vaned member between the impeller and runner. This stationary member allows the torque on the driven shaft to be greater than that on the drive shaft, especially when the driven shaft is stalled. In such a state, the torque can be up to 3.5 times the drive-shaft torque. This capability makes the hydraulic torque converter function like an infinitely variable speed transmission, delivering higher torque at lower output speeds. It is often used in automatic transmissions as a substitute for a gearbox and clutch.1
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The hydraulic torque converter resembles the fluid coupling. Oil transmits power in both. At lower speeds the blades of a pump, or impeller, force oil against the blades of a stator. These blades deflect the oil against a turbine, therefore increasing torque. At higher speeds, as…
Read MoreThe hydraulic torque converter resembles the fluid coupling. Oil transmits power in both. At lower speeds the blades of a pump, or impeller, force oil against the blades of a stator. These blades deflect the oil against a turbine, therefore increasing torque. At higher speeds, as…
Read More 
hydraulic transmissionThe hydraulic torque converter is similar to the hydraulic coupling, with the addition of a stationary vaned member interposed between the runner and the impeller. All three elements are enclosed in a casing containing a liquid, usually oil. The effect of the stationary member is to…
Read MoreThe hydraulic torque converter is similar to the hydraulic coupling, with the addition of a stationary vaned member interposed between the runner and the impeller. All three elements are enclosed in a casing containing a liquid, usually oil. The effect of the stationary member is to…
Read More