Abstract: A heater pattern is arranged on at least one substrate among substrates configuring a package, and a temperature in the package is controlled by controlling a quantity of electricity carried to the heater pattern corresponding to the ambient temperature of a sensor chip in the package.

Abstract: A package is configured by stacking a flat board whereupon a rectangular hole for storing a sensor chip is formed, a flat board whereupon a hole section to be a package inner channel for introducing a measurement target gas into the sensor chip is formed, and a flat board whereupon hole sections which communicate with the package inner channel as an inlet and an outlet of the measurement target gas on the same end surface of the package are formed.

Abstract: A method for making a disposable model for a precision investment casting, which comprises casting a naphthalene or para-dichlorobenzene-containing modeling material into a pattern mold at a temperature of 150.degree. C or less, preferably 80 to 150.degree. C and further preferably at a casting speed of 5 to 0.1 kg/second; the modeling material being optionally admixed with a resin selected from the group consisting of polystyrene, polyethylene, polyvinyl acetate and a mixture thereof as a reinforcing material or comprising a mixture of naphthalene or paradichlorobenzene (preferably 80 to 30% by weight), a wax (preferably 20 to 70% by weight) and the resin as mentioned above (preferably 0.5 to 15% by weight on the basis of the whole weight of the modeling material).

Abstract: There is disclosed a method of burning a ceramic shell mold for use in precision casting for curing the ceramic shell mold. The ceramic shell mold is positioned within a heating compartment while a mass of sand within the heating compartment is fluidized so as to submerge the ceramic shell mold thereinto. Thereafter, particles of the sand are heated to a predetermined curing temperature, which sand particles then heat the ceramic shell mold enveloped by the sand particles.

Abstract: An investment casting method for making a desired casting of a relatively large size by the use of a mold of one-piece construction within close dimensions, which comprises preparing a thermally fusible pattern which is a replica of the desired casting, forming a refractory investment enveloping the thermally fusible pattern, melting the thermally fusible pattern out of the investment leaving a cavity in the refractory investment, and heating the investment to provide a rigid ceramic mold of one-piece construction. Melting of the thermally fusible pattern out of the investment is carried out in contact with a vaporized organic solvent without causing the thermally fusible pattern to thermally expand which may otherwise result in formation of cracks in the refractory, investment, that is, mold.