Abstract: A temperature-dependently actuated 3-port, 2-way valve 1 has a bimetallic disc 22 which closes either a valve seat 15, as shown, or a valve seat 14 when it snaps over into an upwardly domed position. The disc 22 is floatingly supported by two 3-legged springs 23 and 24 acting on its opposite sides. When, as shown, the disc is downwardly domed, only the upper spring 23 acts on the disc 22 and the legs of the lower spring 24 act against abutments 26. The reverse happens when the disc is upwardly domed. In this way the disc is always pressed against one seat or the other only by the appropriate spring and the closure force is independent of the flexural strength of the disc. The floating support of the disc 22 also ensures that it snaps over at or very near the correct operating temperature.

Abstract: An actuator for use as part of an electrically heated thermal delay valve (FIG. 1) or switch (FIG. 2) includes a thermally responsive plate (12) the periphery of which is fixed and the central part of which forms a temperature-dependent control element. The actuator also includes a metal carrier plate (9) which has a PTC element (10) mounted on it and which is free to move in a direction normal to its surface between stop abutments, and at least one spring (11) which electrically contacts the PTC element (10) and biases the carrier plate (9) towards the thermally responsive plate (9) to ensure that it is constantly in thermal contact with the carrier plate (10). This ensures that a direct thermal contact between the PTC element and the thermally responsive plate is constantly maintained which results in consistently reproducible functions being achieved with the apparatus by virtue of this direct thermal contact. The thermally responsive plate (9) may be biased towards the carrier plate (10).

Abstract: An arrangement for heating the intake pipe of a spark-ignited internal combustion engine with electrical heating elements having a positive temperature coefficient. These heating elements are located on a heating plate which forms part of the intake pipe wall, and are held by a carrier member, rigidly fastened to these elements. This carrier member has several elastic plates, one for each heating element, connected to one central current contact surface. The carrier member is centered in the heating plate and is loaded by a compression spring which is centered in the cover of the housing of the arrangement.