摘要:
The object of the invention is to provide plant-derived component-containing polycarbonates with improved color tone, and a process for their production.This object of the invention is achieved by reducing the inorganic impurities in the polymer starting material and by reducing the inorganic impurities in the polymer product.
摘要:
A control system for a lifting device in which a load moves up or down or maintains its position by a rope that is wound up or down by the rotation of a servo motor. It includes a device for measuring a force, a first controller, a second controller and a switching device. A total force that is applied at the lower part of the rope caused by a force for controlling, the mass of the load, and the acceleration of the load is measured. The first controller, based on the measured force computes the direction and the speed of the servo motor, and outputs a signal to it. The second controller determines a stable condition using Popov's stability criterion. The switching device replaces the first controller with the second controller when the value that is measured by the measuring device becomes less than a threshold.
摘要:
A tilting-type automatic pouring method for pouring molten metal from a ladle with an outflow position into a mold. The method includes tilting the ladle forward to pour molten metal into the mold, measuring a weight of poured molten metal, calculating a flow rate of the molten metal flowing out of the ladle based on the measured weight of poured molten metal, estimating a weight of molten metal that will be poured during a backward tilting. The method also includes estimating a total weight of molten metal based on the measured weight of poured molten metal and the estimated weight of molten metal that will be poured during the backward tilting and comparing the estimated total weight of molten metal to a predetermined weight. When the estimated total weight is equal to or larger than the predetermined weight, the backward tilting is started.
摘要:
A resin composition comprising 100 parts by weight of a polycarbonate of which a specific ether diol residue constitutes 40-100 mol % and 1-40 parts by weight of polylactic acid, wherein the polylactic acid is composed of a poly-L-lactic acid component and a poly-D-lactic acid component, and wherein in the melting peak derived from the polylactic acid component during temperature increase for measurement with a differential scanning calorimeter (DSC), the proportion of the melting peak area for 195° C. and above is at least 60% of the sum of the melting peak area for 195° C. and above (high temperature) and the melting peak area for 140-180° C. (low temperature), as determined by measurement of the melting peak derived from the polylactic acid component during temperature increase with a differential scanning calorimeter (DSC).
摘要:
(Problems to be Solved) This invention provides a method that enables molten metal that flows from ladles to drop precisely into a sprue of a mold.(Means to Solve the Problems) The input voltage that is to be supplied to each of the servomotors is controlled so that the molten metal that flows from the ladle drops precisely into a sprue of a mold, the respective servomotors tilting the ladle, moving the ladle backward and forward, and moving the ladle up and down, wherein the method comprises: obtaining a mathematical model covering the locus of the positions where the molten metal that flows from the ladle drops, solving the inverse problem of the mathematical model thus obtained; estimating the position where the molten metal drops from the term for the estimated flow of the molten metal and the term for the estimated position where the molten metal drops; and processing the data on the estimated position where the molten metal drops, whereby the pouring of the molten metal is effected by determining the electrical voltages to be supplied to the respective servomotors, which tilt the ladle, move the ladle backward and forward, and move the ladle up and down, and controlling the three motors based on the electrical voltages thus determined.
摘要:
The present invention provides a tilting-type automatic pouring method wherein a very speedy and highly accurate pouring can be realized, which method pours molten metal into a mold by tilting a ladle that holds the molten metal, and the present invention also provides the storage medium for programs used for the method.The tilting-type automatic pouring method of the present invention uses a) the relationship of (1) the height of the molten metal during backward tilting of the ladle, which height is calculated from the height of the molten metal above the outflow position, which height decreases, when the forward tilting of the ladle stops and from the height of the molten metal that is above the outflow position and that decreases after the backward tilting of the ladle starts, and (2) the weight of the molten metal poured from the ladle into the mold, and b) the model expression for the flow of the molten metal, which expression defines the weight of the molten metal that flows from the ladle into the mold.In the tilting-type automatic pouring method of the present invention, the final weight of the molten metal that is poured is estimated by assuming that the final weight of the molten metal that is poured from the forward tilting of the ladle to its backward tilting is equal to the sum of the weight of the molten metal that is poured at the start of the backward tilting and the weight of the molten metal that is poured after the start of the backward tilting.
摘要:
The present invention provides a method for controlling a process for automatically pouring molten metal by a tilted ladle, wherein the pouring can be performed in a manner that is as close as possible to that of an experienced operator by using a computer that has programs installed for such purpose.The method to control the automatic pouring of molten metal by a ladle comprises controlling a servomotor, corresponding to the desired flow pattern of the molten metal, so that the molten metal can be poured into a mold, wherein the servomotor, which tilts the ladle to pour the molten metal in a mold, is controlled by a computer that has programs installed that control the process of pouring, the method comprising: producing a mathematical model covering the electrical voltage that is supplied to the servomotor for tilting the ladle to a rate of the flow of the molten metal poured by the tilted ladle, solving the inverse problem of the mathematical model thus produced, estimating the rate of the flow of the molten metal by an observer having an exponential damping that uses an extended Kalman filter, based on an electrical voltage being supplied to the servomotor and the weight of the molten metal poured into the mold that is measured by weighing equipment, wherein the measurement is calibrated by eliminating errors caused by the movement of the center of gravity of the object to be measured, treating the rate of the flow of the molten metal and the targeted rate of the flow of the molten metal with a gain-scheduled PI controller, obtaining data on the electrical voltage to be supplied to the servomotor thereby, and controlling the servomotor based on the data on the electrical voltage thus obtained and to be supplied to the servomotor.
摘要:
This invention is aimed to provide a control system for a lifting device that can lift a load that enables the operator to have a good judgment for handling the load, so that an operator can simultaneously hold and control the load.The control system of the lifting device of this invention controls the rotation of a servo motor 1 so that an operator can move a load in a direction and at a speed that he or she desires by applying a force for controlling to the load. The load is hoisted up or down or maintains its position by means of a rope 2. The rope is wound up or down by the rotation of the servo motor in the forward or the reverse direction. The system comprises a means 3 for measuring a force, a first controller means, a second controller means, and a switching means. The means for measuring measures the total force that is applied at the lower part of the rope caused by a force for controlling of the operator, the mass of the load, and the acceleration of the load. In the first controller means, based on the force that is measured by the means for measuring, the arithmetic part computes the direction and the speed of the servo motor, and outputs a signal to the servo motor to have it operate. The second controller means determines a stable condition using Popov's stability criterion. Under this condition, when the load touches the ground, the input and output signals of the servo motor rotating in the forward and the reverse direction are stable. The switching means replaces the first controller means with the second controller means, at the right time, namely, when the value that is measured by the means for measuring becomes less than the threshold.
摘要:
A wholly aromatic polyester carbonate having a good color and excellent heat resistant stability. This polymer had an extremely low alkali metal content of 10 ppm or less. This polymer is advantageously produced by reacting an aromatic dicarboxylic acid, aromatic diol and diaryl carbonate in a specific molar ratio in the presence of a pyridine-based compound as a catalyst.
摘要:
A process for producing a wholly aromatic polyester which is excellent in heat resistance, mechanical properties and yet color and has a high degree of polymerization by melt polymerizing a dicarboxylic acid and a diol directly on an industrial scale at a low cost in a short period of time without esterifying the dicarboxylic acid or diol in advance. To produce the wholly aromatic polyester by reacting and molding an aromatic dicarboxylic acid such as terephthalic acid, an aromatic diol such as 2,2-bis(4-hydroxyphenyl)propane and a diaryl carbonate by heating, a combination of a specific pyridine compound and an alkali metal (bi)carbonate, a combination of a specific pyridine compound and an organic tin compound or a specific titanium compound is existent as a catalyst. Thereby, the wholly aromatic polyester having the above properties is obtained.