Abstract: A shut-off nozzle includes: an injection nozzle in which a flow path is formed; a needle valve provided in the flow path coaxially with the injection nozzle, the needle valve being movable forward and backward in an axial direction; and a guide ring provided in the flow path. The needle valve includes a columnar shaft portion, and the guide ring is configured to guide the forward and backward movement of the needle valve at the shaft portion. An injection device includes: a heating cylinder; a screw provided in the heating cylinder; and the shut-off nozzle provided in the heating cylinder. An injection molding machine includes: a mold clamping device configured to clamp a mold; and the injection device configured to inject a resin.

Abstract: A shut-off nozzle includes: an injection nozzle in which a flow path is formed; a needle valve provided in the flow path coaxially with the injection nozzle, the needle valve being movable forward and backward in an axial direction; and a guide ring provided in the flow path. The needle valve includes a columnar shaft portion, and the guide ring is configured to guide the forward and backward movement of the needle valve at the shaft portion. An injection device includes: a heating cylinder; a screw provided in the heating cylinder; and the shut-off nozzle provided in the heating cylinder. An injection molding machine includes: a mold clamping device configured to clamp a mold; and the injection device configured to inject a resin.

Abstract: A mold clamping device includes: a fixed platen; a movable platen facing the fixed platen; a mold clamping housing; a plurality of tie bars connecting the fixed platen and the mold clamping housing; a plurality of tie bar nuts respectively provided on the plurality of tie bars, and configured to adjust a distance between the fixed platen and the mold clamping housing; a toggle mechanism provided between the mold clamping housing and the movable platen; a plurality of rotation members respectively provided integrally with the plurality of tie bar nuts; one endless string-shaped force transmission member wound around the plurality of rotation members; and a rotation driver configured to transmit a driving force to at least one of the plurality of the tie bar nuts as a drive target tie bar nut.

Abstract: A refractory composition which is suitable for forming a sliding gate to be used at the bottom of a ladle or tundish is provided. The refractory composition comprises 10 to 30 parts by weight of an alumina-magnesia spinel material containing 40 to 70% by weight of Al.sub.2 O.sub.3, 25 to 60% by weight of MgO and 10% or less of impurities, and 70 to 90 parts by weight of a magnesia material containing at least 90% by weight of MgO, wherein the composition contains 10 to 25% by weight of Al.sub.2 O.sub.3 and 75 to 90% by weight of MgO. 1 to 10 parts by weight of Al.sub.2 O.sub.3 material may be further added together with the alumina-magnesia spinel material and the magnesia material, to form the refractory composition.