Patent · US Expired

Thermostatically controlled switch

US5173679A · kind A · utility

3Cited by
4References
20Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 25, 1992
Grant dateDec 22, 1992
Priority date
Expiry dateFeb 25, 2012

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01H37/22
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A housing (10), (54) defines a well which holds a diaphragm assembly (12). The diaphragm assembly has a stud portion (14) that extends through an aperture in the housing and is biased into the housing by a spring (16). The stud portion defines a channel (18) which is received in a slot between arms of a calibration plate (20). Movement of the calibration plate transverse to the axis of the stud portion engages a cam surface (24) to position the diaphragm, more particularly a dielectric button (34) which engages a switch control member (50). As a fluid in a bulb (32) expands, it causes the diaphragm to expand, moving the control member (50) and one end of spring portion (48) causing contacts (46, 52) to open. The temperature or degree of diaphragm extension at which the switch contacts open is adjusted by rotating a shaft (60). As the stem is rotated, a cam follower (76) and cam (70) interact causing a dielectric actuator (64 ) to change the bias force, hence pivot point, of spring elements (44).

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.