Abstract: A communication system includes a power line, a plurality of PLC networks connected to the power line in common, and an electronic control unit for controlling an electric equipment, connected to the power line between the PLC networks. The electronic control unit includes a bypass capacitor that attenuates a communication signal transmitting over the power line.

Abstract: An object is to provide a beverage supply device which can cool cooling water in a water tank provided with a beverage cooling pipe by use of a cooling unit using a refrigerant having little influence on global environment, a beverage dispenser is provided with the beverage cooling pipe (syrup cooling pipe, diluting water cooling pipe, carbonated water cooling pipe) disposed in the water tank to store cooling water, the water tank being cooled by an evaporation pipe, the beverage dispenser passes syrup, diluting water, and carbonated water as beverage ingredients through the beverage cooling pipe to extract beverage, and the beverage dispenser comprises: a cooling unit in which a compressor, a radiator, a capillary tube, the evaporation pipe and the like are connected to one another via a pipe to constitute a refrigerant circuit and which is filled with carbon dioxide as the refrigerant.

Abstract: Plural communication areas are provided, and plural electronic control units for mutually making communication in each of the communication areas are provided. A vehicular power line communication system includes a power line coupling the respective communication areas to one another, branch power lines coupling the respective electronic control units in each of the communication areas to one another, and a battery for supplying electric power to the electronic control units through the power line and the branch power lines. The power line is formed of a +B line turning to a positive polarity and a ground line turning to a negative polarity, which are cabled to be spaced from each other in a part of the power line. The branch power lines superpose communication data thereon, thereby making data communication.

Abstract: An ECU monitoring device includes a driver's seat J/B ECU and an immobilizer ECU both connected to a main battery through a power line. In operation, the immobilizer ECU is formed so as to output a communication signal superimposed on the power line. While the driver's seat J/B ECU is formed so as to receive the communication signal from the power line. When the communication signal is not received by the driver's seat J/B ECU, it judges that the immobilizer ECU is disconnected from the power line on purpose or that a false instrument in place of the immobilizer ECU is connected to the power line falsely. In this way, the ECU monitoring device allows the driver's seat J/B ECU to monitor a connection between the power line and the immobilizer ECU to be monitored.

Abstract: An ASK communication device has a carrier signal generator which is connected to a bus line which outputs carrier signals. One of ECUs, which attempts to transmit data, attenuates carrier signals superimposed on the bus line with predetermined timing by use of a transmission switch and a signal attenuator thereby to cause ASK modulation of the carrier signals. Other ECUs receive the ASK-modulated data superimposed on the bus line by use of a receiver, and obtain data by demodulating the ASK-modulated data.

Abstract: A master station includes a main clock generator using a high precision oscillator such as a crystal oscillator or a ceramic oscillator, and generates a carrier signal used for ASK modulation of a transmission signal in response to the clock signal outputted from the main clock generator. A slave station uses sampling means to sample the carrier signal sent from the master station, and generates a carrier signal used for ASK modulation of a transmission signal based on the sampling data.

Abstract: An ASK communication device includes a master station and slave stations connected to the master station through a bus line. The master station includes a transmission unit for ASK-modulating a carrier signal outputted from an oscillation circuit owned thereby and outputting, to a bus line, ID signals of the respective stations and data transmitted to the respective slave stations in a case of transmitting the data from the master station, and outputting the ID signal of the slave station as a transmission source and the carrier signal to the bus line in a case of transmitting the data from the slave station, and a master-side reception unit for receiving, through the bus line, the data transmitted from the slave station. The at least one slave station includes a slave-side reception unit for receiving the data transmitted from the master station and other slave stations, and an attenuation unit for attenuating and ASK-modulating the carrier signal outputted from the master station to the bus line.

Abstract: An ECU monitoring device includes a monitoring ECU connected to a power line for supplying power from a main battery to an immobilizer ECU. The monitoring ECU includes a high-frequency signal generating circuit for superimposing a high-frequency signal on the power line, a high-frequency signal detecting circuit for detecting the high-frequency signal superimposed on the power line and a CPU for judging a connection between the power line and the immobilizer ECU or between the power line and a false instrument. With the constitution, the ECU monitoring device can detect a situation that the immobilizer ECU is detached from a vehicle with high accuracy, preventing the vehicle from being stolen by theft.