The invention provides a high-temperature open-circuit self-protection type pressure
transmitter. A meter shell is provided with a step-shaped through hole and a step surface; a
piston block
flange plate is located in the large hole section, and a spring is clamped between the
flange plate and the step surface; a large hole section between the upper meter cover and the
piston block forms a sealed inner cavity; the power supply circuit board is fixed, the
signal circuit board is fixed with the
piston block, a spring probe is welded and fixed on the upper surface of the
signal circuit board, a probe head faces a taper hole connecting point arranged on the power supply circuit board, and the hole wall of the taper hole connecting point is coated with
copper for conduction; in a
normal state, the spring is in a half-compressed state, the spring probe is in a full-compressed state, and under the action of upward elastic force provided by the spring, a probe head of the spring probe can be connected through abutting against a corresponding taper hole connecting point on the power supply circuit board; when a short-circuit heating accident occurs, the
internal pressure is increased along with temperature rise, and the piston is pushed to move downwards to disconnect the circuit, so that high-temperature open-circuit self-protection is realized, and the device can be recovered to use after a fault is removed.