Hitachi, Ltd.

Japanese National Railways

Yozo Hibino

Kohji Kamejima

Yasuaki Nara

Hideki Tanaka

Kensaku Oguni

Hideo Nishida

Susumu Nakayama

Junichi Oizumi

Hiromu Yasuda

Morio Tamura

Yoshiyuki Nakano

Kenji Tokusa

Kengo Sugiyama

Yasuo Nabeshima

Hiroshi Ohmachi

Junichi Ooizumi

Sakae Yamada

Yasumasa Ninomiya

The control system for the air-conditioner disclosed herein comprises means for setting a set value of a room temperature, means for detecting an actual value of the room temperature, means for detecting a radiant heat from walls etc. of the room as a radiation temperature, and an operational control means. The operational control means stores a comfort line which defines an inverse proportional relation between the room temperature and the radiation temperature, said comfort line depending upon set value of the room temperature. The operational control means calculates a first control index which is represented by a difference between the actual value and the set value of the room temperature and a second control index which is represented by a difference between the comfort line and the current temperature condition represented by the actual room temperature and the radiation temperature. The room temperature set value is modified in the operatal control means, according to fuzzy rule, on the basis of said first and second control indexes. The operational control means controls the air-conditioner, depending upon a difference between the modified value of the room temperature and the actual value of the room temperature, thereby providing a comfortable air-conditioned environment to a person staying in the room.

Control system for air-conductioner

A monitoring system for a screw compressor for checking the operating conditions of the screw compressor by opening and closing a suction throttle valve located on the suction side of the screw compressor and an air discharge valve located on the discharge side thereof to thereby effect on-off control of the flow rate of the discharged air, wherein the operating conditions of components of the screw compressor are checked both in on-load and unloaded conditions by comparing values of the suction pressure, discharge pressure and discharged air temperature of the screw compressor with respective preset values.

Monitoring system for screw compressor

An absorption cold and warm water system utilizing solar heat in which heat source water obtained by heating water by the solar heat and a main heating source are used is selectively made to function as a warm water system, a first heat pump and a second heat pump in accordance with temperature conditions associated with the heat source water.

Absorption cold and warm water system utilizing solar heat

An absorption cold and warm water system utilizing solar heat includes a low temperature heat generator using as a heating source low temperature warm water obtained by heating water by the solar heat, a high temperature generator using an ancillary heat source as a heating source when the system runs short of the solar heat, and a low temperature generator. The cold and warm water system is provided with an operation device operative, when the cold and warm water system is in condition in which refrigerating and heating outputs can be provided by using the low temperature warm water, to allow the low temperature warm water to be continuously fed to the cold and warm water system and to control the volume of a solution and a refrigerant in circulation in accordance with temperatures of the cold and warm water, to thereby store the solar heat in the cold and warm water system.

Operation device for absorption cold and warm water system utilizing

In an absorption type cold and warm water system, a solution pump and a refrigerant pump are operated when a heat source serving as a drive source of the absorption type cold and warm water system is rendered inoperative as a result of the temperature of cold water and warm water produced by the system reaching an OFF value set beforehand for the heat source. This enables refrigerating and heating abilities stored in the cold and warm water system to be effectively utilized.

Control device of absorption type cold and warm water system

A method of controlling the operation of a refrigerator of a type having a capacity control mechanism adapted to control the capacity of the refrigerator in such a manner as to make the temperature of the cold water supplied to an air conditioner coincide with a predetermined set temperature of cold water. The apparatus is adapted to vary the set temperature of the cold water in accordance with the level of the load imposed on the air conditioner, and to determine the difference of the new set temperature of the cold water with the actually measured temperature of the cold water. The apparatus effects the control of the capacity control mechanism of the refrigerator such that the above-mentioned difference of the temperature is nullified. In consequence, the efficiency of the refrigerator during partial-load operation is remarkably improved.

Apparatus for controlling operation of refrigerator

A method of controlling the operation of multistage centrifugal compressor equipment provided with inlet guide vanes and diffuser vanes at each stage to enable operation to be practiced at a low energy consumption level. The method includes the steps of determining whether the prevailing flow rate, for example, is in a range of flow rates near the desired flow rate or in a range of flow rates remote therefrom; and controlling a combination of the amount of operation of the guide vanes with the amount of operation of the diffuser vanes, which is set beforehand, when the prevailing flow rate is determined to be in the latter range to promptly bring the prevailing flow rate to the desired flow rate level, and effecting fine adjustments of the inlet guide vanes and diffuser vanes to control the angles thereof when the prevailing flow rate is determined to be in the former range, thereby enabling increased efficiency to be achieved in the operation of the compressor equipment.

Method of controlling multistage centrifugal compressor equipment

An apparatus with sensor mounted on a spreader for handling articles of a rectangular parallelepiped shape for detecting elements in plate form attached to both sides of such handling articles and both sides of the handling article loading and unloading bed of freight cars and trucks for conveying such handling articles, in order to position the spreader by detecting the detecting plate by the sensor. The sensor detects the deflections of the spreader with respect to the detecting plate, and the spreader is slightly moved for correcting the deflections so as to accurately position the spreader with respect to the article or the bed of a freight car or a truck.

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Ibaraki, Japan

Yozo Hibino