Accumulator; Pressure Switch - Honda Prelude 1993 Service Manual

Accumulator
The accumulator is a pneumatic type which accumulates high-pressure brake fluid fed from the pump incorporated in the
power unit. When the anti-lock brake system operates, the accumulator and the power unit supply high-pressure brake
Jluid to the modulator valve via the inlet side ot the solenoid valve.
ACCUMULATOR
ALADDER
Pressure Switch
The pressure switch monito,s the pressure accumulation (pressure lrom the pump) in the accumulator and is turned off
when the pressure becomes lower than a prescribed level. When the pressure switch is turned oft, the switching signal is
sent to the ABS control unit. Upon receiving the signal, the ABS control unit activates the pump motor relay to operate
the motor. lf the pressure doesn't reach the prescribed value, the ABS indicator light comes on.
ODeration
When the pressure in the accumulator rises, the Bourdon tube in the pressure switch deforms outwards. When the
free end of the Bourdon tube moves more than the prescribed amount, the micro-switch is activated by the force of
the spring attached to the sensing lever. When the pressure in the accumulator decreases due to anti-lock brake
system operations. the Bourdon tube moves in the direction opposile to the one described above, and the micro-
switch is eventually turned off. Upon receiving this signal, the ABS control unit activates the motor relay to operate
the motor.
SENSING LEVER
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