Abstract: An injection molding apparatus includes an electric motor, a torque variable mechanism that changes an output torque of the electric motor, and a screw driving unit that transmits the output torque of the torque variable mechanism to a feed screw, whereby the feed screw is turned by the electric motor, the torque variable mechanism and the screw driving unit. The torque variable mechanism applies, to the feed screw, a torque equivalent to a hydraulic drive. The electric motor is interchangeable with a hydraulic motor to enable the injection molding apparatus to change between electric and hydraulic drive of the feed screw.

Abstract: An injection molding apparatus is on the basis of a hydraulic injection molding device, and the apparatus includes an electric motor, a torque variable mechanism that changes output torque by the electric motor, and a screw driving unit that transmits the output torque by the torque variable mechanism to a screw. The screw is turned by the electric motor, the torque variable mechanism, and the screw driving unit. The torque variable mechanism applies, to the screw, torque equivalent to a hydraulic drive.

Abstract: A problem of the invention is to provide a process of producing polyesters having a stable quality and a process of producing polyesters with a greatly reduced load against the environment. The invention relates to a process of producing polyesters by using a polycondensation reaction apparatus provided with one or more sets of an ejector, a condenser placed in the downstream portion of the ejector and a hot well tank connected to the condenser via a barometric leg and including a step of driving the ejector by a vapor composed mainly of 1,4-butanediol, condensing the vapor composed mainly of 1,4-butanediol as discharged from the ejector in the condenser placed in the downstream portion of the ejector, and making the reactor in a reduced pressure state to undergo polycondensation reaction, characterized in that the concentration of tetrahydrofuran contained in a sealing liquid in at least one hot well tank is not more than 4% by weight.

Abstract: A method of contact catalytic reaction by introducing a gas and a liquid into a lower part of a reaction zone comprising a liquid phase and a catalyst-packed bed held therein, where the catalyst-packed bed is a fixed bed.

Abstract: A problem of the invention is to provide a process of producing polyesters having a stable quality and a process of producing polyesters with a greatly reduced load against the environment. The invention relates to a process of producing polyesters by using a polycondensation reaction apparatus provided with one or more sets of an ejector, a condenser placed in the downstream portion of the ejector and a hot well tank connected to the condenser via a barometric leg and including a step of driving the ejector by a vapor composed mainly of 1,4-butanediol, condensing the vapor composed mainly of 1,4-butanediol as discharged from the ejector in the condenser placed in the downstream portion of the ejector, and making the reactor in a reduced pressure state to undergo polycondensation reaction, characterized in that the concentration of tetrahydrofuran contained in a sealing liquid in at least one hot well tank is not more than 4% by weight.

Abstract: In yielding diacetoxybutene by feeding butadiene, acetic acid, and oxygen in the presence of a solid catalyst containing palladium, the butadiene can be efficiently reacted to produce diacetoxybutene in high yield by feeding an oxygen-containing gas containing 7 mol % or more oxygen as fine bubbles to a reaction zone containing the solid catalyst.

Abstract: In yielding diacetoxybutene by feeding butadiene, acetic acid, and oxygen in the presence of a solid catalyst containing palladium, the butadiene can be efficiently reacted to produce diacetoxybutene in high yield by feeding an oxygen-containing gas containing 7 mol % or more oxygen as fine bubbles to a reaction zone containing the solid catalyst.

Abstract: In yielding diacetoxybutene by feeding butadiene, acetic acid, and oxygen in the presence of a solid catalyst containing palladium, the butadiene can be efficiently reacted to produce diacetoxybutene in high yield by feeding an oxygen-containing gas containing 7 mol % or more oxygen as fine bubbles to a reaction zone containing the solid catalyst.

Abstract: Disclosed is a hydraulic drive system of an injection molding machine which has a hydraulic power source equipped with a fixed-displacement hydraulic pump and a servomotor for driving the hydraulic pump and functioning to control discharge rate and discharge pressure of the hydraulic pump through control of the rotational speed of the servomotor. In the hydraulic drive system, a pilot port of a control valve connected to a hydraulic actuator of the injection molding machine is connected to a supply line of working fluid discharged from the hydraulic power source, via a series circuit including a check valve for preventing backflow from the pilot port and a changeover valve.

Abstract: A vibration applying apparatus associated with an injection molding machine for applying vibrational repetitive movements to a melt of molding materials includes a rod having a tip end received inside a heating cylinder and disposed in the proximity of a nozzle of the heating cylinder, a stationary guide supporting the rod such that the rod is movable back and forth, a rotating shaft being orthogonal to the rod, a drive motor for rotating the rotating shaft, and a cam mechanism acting between the rotating shaft and the rod so as to convert rotary motion of the rotating shaft into linear reciprocal motion of the rod. With the apparatus thus arranged, the tip end of the reciprocating rod applies vibrational repetitive movements to the melt of molding material, thereby lower the viscosity of melt. The frequency of vibrational repetitive movements can be varied by changing the rotational speed of the drive motor.

Abstract: A material feeding apparatus including a material container as a hopper serves to feed a molding material sealably received in the material container to a molding machine via a heating sleeve. The material feeding apparatus includes as essential components a material container molded of a transparent synthetic resin or a translucent synthetic resin so as to enable a quantity of molding material remaining in the material container to be visually confirmed from the outside, and an adapter of which one end is formed in the shape of an open end part to be threadably fitted into an opening portion of the material container and of which the other end is formed in the shape of an open end part to be fitted onto a receiving member of the molding machine. To openably shut the interior of the material container, a shutter is slidably displaceably arranged in the adapter.

Abstract: A clamping apparatus of molding machine including a base; a fixed board disposed on the base; a movable board movable relative to the fixed board; a plurality of mold clamping cylinders disposed in predetermined positions of the fixed board, the mold clamping cylinders each having a mold clamping piston with a tie bar reception hole and a tie bar connection device disposed on the mold clamping piston; a plurality of tie bars with a thread at their one end, the tie bars being disposed in correspondence with the mold clamping cylinders on the movable board; a plurality of mold opening/closing cylinders for moving the movable board; and an axially movable sleeve associated with each clamping cylinder for adjusting an axial position of an associated piston to adjust an engagement position of the tie bar connection device, the sleeve being disposed in an opening in the fixed board and forming an extension of the tie bar reception hole, with one end of the sleeve abutting against a reception wall provided in each p

Abstract: A safety apparatus for a clamping device which includes a machine base, a first fixed board fixed on the base, a movable board movably disposed on the base, either a second fixed board or a bearing member fixed to the base behind the movable board, and a safety door slidably disposed on the base between an open and a closed position. The safety apparatus includes an engagement device disposed on the movable board, the engagement device having a stopper member which is vertically movable between an engaged and a disengaged position when the safety door is opened or closed, a safety rod disposed between the first fixed board and either the bearing member or the second fixed board, the safety rod having a plurality of engagement portions spaced therealong, and a drive device disposed on either the bearing member or the second fixed board for axially moving the safety rod.

Abstract: A clamping apparatus of molding machine including a base; a fixed board disposed on the base; a movable board movable relative to the fixed board; a plurality of mold clamping cylinders disposed in predetermined positions of the fixed board, the mold clamping cylinders each having a mold clamping piston with a tie bar reception hole and a tie bar connection device disposed on the mold clamping piston; a plurality of tie bars with a thread at their one end, the tie bars being disposed in correspondence with the mold clamping cylinders on the movable board; a plurality of mold opening/closing cylinders for moving the movable board; and a mold thickness adjustment device having a movable stopper for contacting an end of each tie bar to control the axial position of each of the tie bars with respect to the connection devices during clamping.

Abstract: A clamping apparatus of molding machine including a base; a fixed board disposed on the base; a movable board movable relative to the fixed board; a plurality of mold clamping cylinders disposed in predetermined positions of the fixed board, the mold clamping cylinders each having a mold clamping piston with a tie bar reception hole and a tie bar connection device disposed on the mold clamping piston; a plurality of tie bars with a thread at their one end, the tie bars being disposed in correspondence with the mold clamping cylinders on the movable board; a plurality of mold opening/closing cylinders for moving the movable board; and a differential circuit connected between a front oil chamber and a rear oil chamber of each of the plurality of mold clamping cylinder.

Abstract: A material feeding apparatus including a material container as a hopper serves to feed a molding material sealably received in the material container to a molding machine via a heating sleeve. The material feeding apparatus includes as essential components a material container molded of a transparent synthetic resin or a translucent synthetic resin so as to enable a quantity of molding material remaining in the material container to be visually confirmed from the outside, and an adapter of which one end is formed in the shape of an open end part to be threadably fitted into an opening portion .Iadd.of the outer wall .Iaddend.of the material container and of which the other end is formed in the shape of an open end part to be fitted onto a receiving member of the molding machine. To openably shut the interior of the material container, a shutter is slidably displaceably arranged in the adapter.