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(Multiplate Clutch, Basic Function - GF27.51-P-2003A)

Model all with transmission 725 

Example illustration of automatic transmission with multiplate clutches 

G14472109Courtesy of MERCEDES-BENZ USA

Shown on automatic transmission with multiplate clutches 

G14472110Courtesy of MERCEDES-BENZ USA

Overview 

This document contains information on:

General 

A multiplate clutch distributes the clamping force to several friction surfaces between the individual inner and outer plates and therefore produces a frictional connection.

Function 

The transmission achieves different gear ratios via different combinations of sun gear, ring gear and planetary gears. The sun gear, ring gear and planetary gears each have their own shaft, which is frictionally connected or disconnected via the respective multiplate clutch.

A multiplate clutch consists of several, alternating in series, inner plates (6) located on an inner plate carrier and outer plates (5) located on an outer plate carrier. Inner and outer plates produce the clutch pack. The inner plates are coated on both sides with friction linings for multiplate clutch K38 (2) and K27 (3). In contrast, the outer plates are coated with friction linings in multiplate clutch K81 (1). The contact pressure of the inner and outer plates is created with oil pressure. The outer plates are connected to the respective hollow shaft by teething. During the journey, the electrohydraulic controller unit actuates different oil holes and enables the processes described below. In order to enable different gear ranges, the torque converter lockup clutch separates the power flow on the transmission input side before the shift operation. By discharging oil pressure, the multiplate clutch opens or closes. A frictional connection of the gearwheels changes the gear ratio between the transmission input and the main shaft at the transmission output.