Gear Unit - Bosch TCA640 Series Repair Instruction

4.4

Gear unit

The gear unit is the drive for the brewing unit.
The gear motor is actuated at +/– 16 V DC and transfers its power via
gears to a drive shaft which is connected to the brewing unit.
4.4.1 Front housing
Micro switches (S1 and S2) are attached to the front housing of the
gear unit. These micro switches measure the position of the gears and
the brewing unit via a cam (B) connected to the drive shaft.
58300000120060_ARA_en_c.doc – 18.09.09
Note: From production date FD8701 on the drip tray
is monitored by an additional micro switch in the
appliance. If the drip tray is pulled out, the micro switch
opens and interrupts the power supply to the gear motor
via the power module.
4.4.2 Rear housing
On the rear housing section of the gear unit the drainage valve (B) is
attached to the expansion chamber (C). This valve controls the
passage of water from and to the brewing unit. The micro switch (D) is
actuated by the lock on the brewing unit. The drive shaft (E) is the
connection to the brewing unit.
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