Abstract: A valve spring includes a nitrided layer, and a core portion that is further inward than the nitrided layer. A chemical composition of the core portion consists of, in mass %, C: 0.53 to 0.59%, Si: 2.51 to 2.90%, Mn: 0.70 to 0.85%, P: 0.020% or less, S: 0.020% or less, Cr: 1.40 to 1.70%, Mo: 0.17 to 0.53%, V: 0.23 to 0.33%, Ca: 0.0001 to 0.0050%, Cu: 0.050% or less, Ni: 0.050% or less, Al: 0.0050% or less, Ti: 0.050% or less, and N: 0.0070% or less, with the balance being Fe and impurities. In the core portion, a number density of V-based precipitates having a maximum diameter ranging from 2 to 10 nm is 500 to 8000 per ?m2, and in the core portion, a numerical proportion of Ca sulfides with respect to a total number of oxide-based inclusions and sulfide-based inclusions is 0.20% or less.

Abstract: A storage apparatus such as a refrigerator includes a heat-insulated housing having a storage compartment defined by a ceiling, a bottom, two side walls, and a rear wall and a front opening, and a partition frame including a horizontal frame and a vertical frame and mounted on the heat-insulated housing so as to partition the front opening into a plurality of access openings, the access openings having doors respectively. The horizontal frame is formed into a single member fixed to both side walls of the heat-insulated housing so as to extend between them. The vertical frame is formed so as to extend between the ceiling of the heat-insulated housing and the horizontal frame and/or between the bottom of the heat-insulated housing and the horizontal frame.

Abstract: The refrigerator of this invention includes a thermal insulating box, an upper storing box and a lower storing box within the thermal insulating box, and a cooling unit arranged above the upper storing box. An interior space within the thermal insulating box is divided into a first passage communicating with a cold air blowing side of the cooling unit to cool the storing box while lowering the cold air and a second passage communicating with a cold air sucking side of the cooling unit to cool the storing box while raising the cold air descended down to the bottom part of the thermal insulating box and to return the cold air to the cooling unit. A space having the cooling unit stored therein is divided by a partition wall into a first chamber having the cooling unit arranged therein and a second chamber having an air blowing fan arranged therein. The partition wall is provided with through-holes at locations corresponding to the cold air passage within the first chamber.

Abstract: There is disclosed a refrigerator comprising a first passage defined in a space in the interior of a heat-insulating box to guide cold air from a evaporator downwardly, and a second passage which guides the cold air that has flowed downwardly in the first passage and rises to return to the evaporator, a partition plate which is disposed within the first passage to divide the passage into a passage which communicates the first passage with the second passage in order to allow the flow of the cold air in contact with the upper storage box, and a passage communicating with the second passage, allowing the cold air to flow into the upper storage box out of contact with the upper storage box; a regulating means which is disposed in a cold air passage from the evaporator, and regulates the flow of the cold air into the passage; and a cold air introducing means disposed in the passage.

Abstract: A refrigerator comprising a thermal insulation box, a plurality of storing boxes, a cooler, a horizontal passage and a partition plate, wherein the cold air coming from any one of the upper and lower internal spacings is communicated within the horizontal passage along the partition plate, and further the internal spacing of the thermal insulation box is divided into a first passage and a second passage, the horizontal passage and a first passage are divided into an upper segment and a lower segment by a partition plate, and the upper passage and the lower passage defined in the horizontal passage are communicated at a side opposite to a side communicating with the first passage.