SENSOR WATER FREEZE PROTECTOR

摘要

Apparatus that detects the pressure of water that can move through a water channel (26) towards and away from a pressure sensor (22), wherein the apparatus is constructed to avoid damage from freezing water. The water channel is constructed with a narrow channel portion (40) and a wide channel portion (42) connected in series, with the narrow channel portion lying closer to the pressure sensor. When the ambient temperature falls below the freezing temperature of water, water in the narrow channel portion freezes before water in the wide channel portion freezes, and frozen water in the narrow channel portion acts like a plug to prevent water (or ice) from moving toward the pressure sensor.

主权项

1. A pressure detector that has a water inlet and a pressure sensor (22) for sensing the pressure of water in said inlet, said inlet including a channel (26) that carries water toward and away from said pressure sensor, wherein said water in said channel can freeze when the ambient temperature falls below the water freezing temperature, wherein:
said channel includes narrow (40) and wide (42) channel portions lying in series, with said narrow channel portion lying closer to said pressure sensor than does said wide channel portion, said channel including channel walls that have inside surfaces that form said channels and outside surfaces exposed to the ambient temperature; said narrow channel portion is of smaller cross-sectional area than said wide channel portion, whereby to cause water in said narrow channel portion to freeze and act as a plug before water in said wide channel portion freezes.