Mitsubishi Denki Kabushiki Kaisha

Hitchi, Ltd.

Hitachi, Ltd., Trustee, for the Benefit of Hitachi Air Conditioning Systems Co., Ltd.

Cleanup Corporation

Hitachi, Ltd., Tokyo, Japan, As Trustee for the Benefit of Hitachi Air Conditioning Systems Co., Ltd., Tokyo, Japan, Beneficiary

Masanori Takagi

Shunichi Wada

Tadashi Takai

Yukio Ito

Yasuo Naito

Kazuhisa Nishino

Makoto Ito

Tomotsune Taira

Hiroshi Sato

Takayuki Kifuku

Shigeki Ohtagaki

Kazunori Miura

Hideto Watabe

Makoto Itoh

Yoshinori Momose

Masahisa Kujiraoka

A converter unit connected to a monitor apparatus for monitoring and controlling a plurality of air conditioners, including: PAC transmission software for transmitting a setting data from the monitor apparatus regarding a running start/stop state, a running node, an air quality and a temperature, respectively of the air conditioners, to a transmission path, and for receiving running data regarding a temperature and a pressure of a component during the refrigerating cycle from the transmission path; transmission software for receiving the setting data from the monitor apparatus and transmitting the running data to the monitor apparatus; and a converter to convert the running data for the PAC transmission software to a running data for the transmission software, and to convert the setting data for the transmission software to a setting data for the PAC transmission software, respectively, wherein the running data is collected from the control message at a predetermined interval, and the collected running data is transmitted to the monitor apparatus; and wherein the setting data is transmitted to the transmission path if the setting data is changed.

Air conditioner management system and converter unit therefor

A service system for air conditioner is provided which offers a total solution to a wide range of fields, from the customer relationship management covering individual users, building owners and administrators and building management companies to the maintenance and management, manufacture, design, and development on the part of the manufacturer. The service system includes a monitoring center which has the customer database, an operation information database for storing operation information of air conditioners for each customer, and a device information database having device information on the air conditioners related with each customer of the customer database. The monitoring center, upon deciding that there is anomaly in the operation information, dens to the cellular phone over the Internet the information representing the content of the anomaly and the customer information and device information associated with the operation information which was judged abnormal.

Service system for air conditioner and server system for monitoring center

A service system which includes the monitoring center which has a customer database, an operation information database for storing operation information of the air conditioners for each customer, and a device information database having device information on the air conditioners related with each customer of the customer database. When the system decides that there is anomaly in the operation information, the monitoring center sends to the cellular phone over the Internet information representing the content of the anomaly and customer and device information associated with the operation information which was judged abnormal.

A method of detecting the angle of rotation of a DC motor includes the steps of: driving the DC motor with a predetermined torque for a predetermined period of time which is selected so that the angular acceleration of the DC motor is substantially constant during the above period of time; and calculating the angle of rotation of the DC motor from the driving time period and the voltage generated by the DC motor after the driving of the DC motor is stopped. This method makes it possible to accurately detect the angle of rotation and the load torque using an apparatus having a simple structure.

Method of detecting the angle of rotation and load torque of a DC motor,

A motor for a motor-assisted power steering device is controlled with a control value which is obtained by detecting an error between an actual steering torque which has undergone phase lead compensation and a target steering torque, and by summing a proportional value, an integration value and a differentiation value of the error, or with a control value which is obtained by detecting an error between actual steering torque and a target torque; obtaining a proportional value, an integration value and a differentiation value of the error; clipping the lower limit value of the integration value with a first clipping circuit, and clipping the upper and lower limit values of motor-controlling quantity obtained by summing the proportional value, the integration value and the differentiation value by using a second clipping circuit.

Motor-assisted power steering control device

A power steering system for a motor vehicle comprises a speed sensor 11, a steering torque sensor 12, a current calculating/driving circuit 21 for outputting a motor current command value on the basis of the vehicle speed and the steering torque, an assist torque generating electric motor 10 coupled to the steering system through an electromagnetic clutch 9, a clutch control circuit 50 for controlling a coupling effort of the electromagnetic clutch, an abnormal torque decision calculating circuit 31 for arithmetically determining an abnormal torque and a vehicle speed corresponding to the abnormal torque for a predetermined reference temporal duration to thereby output both an abnormal torque decision value indicating an abnormal torque corresponding to the vehicle speed detected by the vehicle speed sensor and the reference temporal duration, a load torque arithmetic circuit 33 for arithmetically determining both a load torque value indicating a sum of the steering torque detected by the steering torque sensor and an assist torque generated by the electric motor and a temporal duration of the load torque value, a torque comparison circuit 35 for comparing the load torque value with the abnormal torque decision reference value and comparing the temporal duration of the load torque value with the reference temporal duration, and a motor fault monitor/control circuit 40 responsive to results of the comparisons indicating that the load torque value is greater than the abnormal torque decision value and that the temporal duration of the load torque value is not shorter than the reference temporal duration, to thereby control the clutch control circuit so that the coupling effort of the electromagnetic clutch is lowered in a continuous manner to a predetermined coupling effort which permits manual steering.

Control apparatus for motor-driven power steering system of motor vehicle

A motor-driven power steering control system of a motor vehicle for assisting a driver in manipulating a steering wheel by making use of an assist torque generated by a reversible motor which is operatively coupled to a steering mechanism of the motor vehicle includes an electric reversible motor mechanically coupled to a steering system of the motor vehicle through an electromagnetic clutch, a motor drive circuit, an H-bridge switching driver circuit for driving the electric reversible motor in forward or reverse direction under the control of the motor drive circuit, and a clutch control circuit for controlling the electromagnetic clutch. A motor voltage detection circuit for detecting terminal voltages at both terminals of the electric reversible motor is provided for generating a voltage signal of high level and subsequently a fail-safe signal of a low level on the basis of the high-level voltage signal when both of the terminal voltages are approximately zero, while generating a voltage signal of a low level and subsequently a fail-safe signal of high level on the basis of the low-level voltage signal unless both of the terminal voltages are approximately zero. A switch is connected between an electric power source and the switching drive circuit and the clutch control circuit. A microcomputer fetches the fail-safe signal from the motor voltage detection circuit to thereby open the switch for interrupting the power supply to the reversible motor and the clutch control circuit when the fail-safe signal is at the low level.

Control apparatus for reversible motor and motor-driven power steering

An electric locker apparatus with a plurality of locker boxes each having an electric lock device including a latch member normally maintained by a stopper member in a lock position in engagement with the door of the box, and biased toward an unlock position wherein the door can be opened, and an actuator responsive to electric command signal, with an output member movable into an operative position for allowing the latch member to be released from the stopper member and moved into the unlock position. The apparatus further includes an emergency unlocking device for forcibly moving the output member of the actuator into the operative position without requiring input of the command signal. The unlocking device has an emergent key cylinder into which an emergent key can be inserted from outside. The angular motion of the key is converted into a linear motion of the output member of the actuator toward the operative position.

Growing community of inventors

Tokyo, Japan

Masanori Takagi