Abstract: A rack bar includes: a rack tooth row including a plurality of rack teeth meshing with pinion teeth; a hardened layer provided continuously over an entire circumference of the rack tooth row; and a center portion provided inside the hardened layer and having lower hardness than the hardened layer. When the rack bar is viewed in an axial direction of the rack bar, a depth of the hardened layer from the following positions i), ii), and iii) increases in this order: i) a bottom land of the rack teeth; ii) a side of the rack bar relative to the bottom land; and iii) a back of the rack bar relative to the bottom land.

Abstract: A rack bar includes: a rack tooth row including a plurality of rack teeth meshing with pinion teeth; a hardened layer provided continuously over an entire circumference of the rack tooth row; and a center portion provided inside the hardened layer and having lower hardness than the hardened layer. When the rack bar is viewed in an axial direction of the rack bar, a depth of the hardened layer from the following positions i), ii), and iii) increases in this order: i) a bottom land of the rack teeth; ii) a side of the rack bar relative to the bottom land; and iii) a back of the rack bar relative to the bottom land.

Abstract: A fluidized bed incinerator having a combustion furnace includes first to fourth combustion sections. Fuel is supplied to the first combustion section and an combustion exhaust gas is exhausted after the fourth combustion section. First to fourth airs are supplied to the first to fourth combustion sections in first to fourth air surplus rates, respectively. The second air surplus rate is equal to or more than the first air surplus rate, the third air surplus rate is equal to or more than the second air surplus rate, and the fourth air surplus rate is equal to or more than the third air surplus rate.

Abstract: A fluidized bed incinerator having a combustion furnace includes first to fourth combustion sections. Fuel is supplied to the first combustion section and an combustion exhaust gas is exhausted after the fourth combustion section. First to fourth airs are supplied to the first to fourth combustion sections in first to fourth air surplus rates, respectively. The second air surplus rate is equal to or more than the first air surplus rate, the third air surplus rate is equal to or more than the second air surplus rate, and the fourth air surplus rate is equal to or more than the third air surplus rate.

Abstract: A particle movement controller, being disposed between a first fluidized bed, to where particles are supplied, and a second fluidized bed, from where particles are discharged, which controls the moving amount of the particles from the first fluidized bed to the second fluidized bed, is improved to have a substantially proportional characteristic without a hysteresis. Flow rate control nozzle pipes 30a, 30b, . . . , 30j made of horizontal pipes are disposed vertically at intervals and nozzle holes 31 are formed in a lower surface of each of the nozzles. An amount of air emitted from each nozzle hole 31 is controlled using opening and closing valves 33a, 33b, . . . , 33j or flow rate adjustment valves 35a, 35b, . . . , 35j (FIG. 2).

Abstract: In an engine valve comprising a valve body of an iron base material, a Stellite or similar alloy is clad on the body using a laser beam with a sufficient energy to form a cladding layer as a valve face such that the iron from the body-forming iron base material is diffused into the cladding layer throughout its thickness through an interface layer between the cladding layer and the valve body, whereby the cladding layer has 5 to 15 wt % of iron diffused and the interface layer has an iron content continuously decreasing from the iron content of the body-forming iron base material to that of the cladding layer.