Abstract: A disc-shaped diaphragm 16 is fixed on a protruding portion 15a formed on the bottom of case 15. Piezoelectric elements 17 and 18 are bonded on upper and lower surfaces of the diaphragm 16. A printed circuit board 24 closes the opening of case 15. Outer surfaces of case 15 and printed circuit board 24 are covered by a resin package 28. Lead terminals 22 and 23 are held by a lead holding member 21. Lend terminals 22 and 23 connect the piezoelectric elements 17 and 18 with a circuit on printed circuit board 24. With this arrangement, it becomes possible to provide an acceleration sensor used in an air bag system which is capable of reducing the number of parts and simplifying the structure.

Abstract: An atmospheric oven containing an atmospheric gas kept at a predetermined purity accommodates a transport for transporting an object to be heated along a predetermined transporting path. A rectangular sectioned tubular body for preventing the gas from flowing outside the oven extends a certain length from an entrance of the oven and an exit of the oven and has a sectional area necessary for passing the object through the tubular body.

Abstract: An atmospheric oven containing an atmospheric gas kept at a predetermined purity and accommodates a transporting means for transport an object to be heated along a predetermined transporting path. A includes a cylindrical portion for preventing the gas from flowing outside the oven, extends in a certain length from an entrance of the oven and an exit of the oven and has a sectional area necessary for passing the object through the portion.

Abstract: A multilayer ceramic substrate comprises plural conductive layers and insulation layer for insulating the plural conductive layers, and the insulation layer is made of an inorganic composition comprising at least one member selected from the group of Al.sub.2 O.sub.3 and ZrO.sub.2, SiO.sub.2, PbO, and at least one member selected from the group of BaO, CaO and ZnO in predetermined range. The multilayer ceramic substrate can be sintered at low temperature in the air and is splendid in a heat resistance, a solderability and resistance value of the insulation layer and furthermore, a microcrack is not caused in a laser trimming of a top resistance film.