GB663053A - Improvements in and relating to thermostatic control mechanism - Google Patents

Abstract

663,053. Thermally-actuated valves. CANNON IRON FOUNDRIES, Ltd. Feb. 14, 1950 [Feb. 18, 1949] No. 4432/49. Class 135 A valve for controlling the supply of fuel to an oven is itself controlled by a thermal element, and means to adjust the control point of the device comprises a ball located in a wedge-shaped space between juxtaposed surfaces pertaining respectively to the thermal element and to the valve, the ball being so connected to the setting device that it is moved positively in both senses. In an embodiment, the valve housing is provided with an inlet 4 leading to a groove 2 and an outlet (not shown) leading from a groove 3, and communication between the two grooves is controlled by a valve 7. The valve is loaded by a spring 8 and carries a short spindle 13 which can slide in a bore also housing a slidable member 16 carried by the thermal element. The latter comprises an invar steel rod 7 connected at its lower end to a brass tube 18. Movement of member 16 is transmitted to the valve spindle 13 through a ball 28, and, as the upper surface of member 16 is obliquely shaped, adjustment of the position of the ball in the wedge-shaped space between the two members will adjust the datum control point. Ball 28 runs in grooves in the two abutting surfaces and is carried by a rod whose other end is ball-shaped and is housed in a socket in a screwed rod 21 carrying a setting knob 23. A screwed sleeve 20 interposed between the rod 21 and the housing enables the initial adjustment of the ball 28 to be made. Niting pins 25, 26 limit the rotation of the setting rod, and a pin 30 carried by the valve housing engages in a slot in valve disc 7 and prevents the latter from rotating. A gauze filter 5 is fitted in the inlet.