Abstract: A multiplex transmission system according to the present invention is provided with a plurality of multiplex nodes which are connected in parallel with two common buses so that data are transmitted between the nodes. A receiver circuit of each multiplex node includes a passive potential detector section and bias sections. In case of any trouble on the buses, in this multiplex transmission system, the passive potential detector section detects the respective passive-mode potentials of the buses, controls the bias sections in accordance with the detected passive potentials, and sets input potentials within a predetermined range, thereby enabling data transmission between the multiplex nodes.

Abstract: A terminal node (40); which includes a first bias unit (41) for biasing a first transmission line (10), out of two common transmission lines (10, 11), to a power supply potential, a second bias unit (42) for biasing a second transmission line (11) to the ground potential, and a communication control unit (43) for controlling data transmission. Another terminal node (50), which includes a communication control unit (51) is also provided. Connecting terminals (44 to 47, 52 to 55) are provided which connect the bias units (41, 42) and the communication control units (43, 51) of the terminal nodes (40, 50) to the transmission lines (10, 11) at two points for each line, and the terminal nodes (40, 50) are daisy-chain-connected to the transmission lines (10, 11) by means of the connecting terminals.

Abstract: A multiplex transmission system for automotive vehicles includes a plurality of communication nodes interconnected via a common multiplex transmission line.

Abstract: A transmission failure diagnosis apparatus for use in a multiplex transmission system which sends and receives data by time division communication among a plurality of nodes connected by a common transmission path. This transmission failure diagnosis apparatus comprises a reception circuit, connected in the transmission path, for receiving a transmission signal on the transmission path, an amplitude detection circuit for detecting the signal amplitude of a transmission signal received by this reception circuit, and a judgment circuit for judging failures in the system on the basis of the amplitude of the transmission signal detected by the amplitude detection circuit.

Abstract: A multipath transmission system for an automobile according to the present invention comprises a plurality of multiplex transmission units connected in parallel with each other to one common bus. Each transmission unit is assigned to one of groups in which various devices attached to the automobile are classified. The transmission unit includes a sending circuit for transmitting the multiple signals from the devices in the group concerned to the other units through the bus. The system further comprises a power source for always applying electric power to the sending circuit of at least one of the multiplex transmission units. Only that multiplex transmission unit to which the electric power is always applied is provided with a bias circuit which sets the potential of the multiple signals on the bus when the multiple signals are supplied from the sending circuits of any multiplex transmission unit to the bus.

Abstract: A multiplex transmission system, in which a node as a transmission node transmits data frame by frame to a transmission path, and a plurality of other nodes, as reception nodes, returns a reception acknowledgment signal to the transmission path upon proper reception of the frame of data. Each of the reception nodes which properly received the frame returns the reception acknowledgment signal specific thereto to that division of a reception acknowledgment signal area in the frame which corresponds to this node. Each node discriminates the success/failure of signal transmission, by comparing the information registered beforehand in its reception acknowledgment signal table with the information in the reception acknowledgment signal area. When the information of the reception acknowledgment signal table does not coincide with that of the reception acknowledgment signal area, the transmission node re-transmits the frame and the reception acknowledgment signal tables of all the nodes are updated.

Abstract: A multiplex transmission system, in which a plurality of nodes are coupled together through a transmission path, and a node as a transmission node transmits a frame of data including a data area containing transmission data, to other nodes as reception nodes through the transmission path. The frame of data includes a data valid/invalid area having the same bit length as the data area and indicating, bit by bit, the validness/invalidness of the data carried by the corresponding bits in the data area. The system need not be modified depending on the model and grade of vehicles, and can be used widely and applied to various options by the use of a signal allocation system common to different models and grades of vehicles.

Abstract: A multiplex transmission system, in which one of a plurality of nodes, as a transmission node, mutually coupled together through a transmission path transmits data frame by frame to at least one of other nodes as at least one of reception node, and the reception node returns a reception acknowledge signal to the transmitting node upon proper reception of the frame of data. A reception acknowledge signal area comprising a plurality of bits is provided following the frame transmitted from the transmitting node. The reception acknowledge signal area is divided into a plurality of bit areas which are respectively assigned to the plurality of nodes. The reception node returns the reception acknowlege signal to the transmitting node from the respectively-assigned bit areas of the reception acknowledge signal area.

Abstract: A plastic optical fiber cable with a ferrule in which a plastic sheath of the end side of the optical fiber cable is removed to expose a plastic optical fiber from the end of the optical fiber cable, and the ferrule is secured to the outer periphery of the end side of the optical fiber cable, wherein the ferrule is axially formed as a combination of a plastic cylindrical member for forming the end of the ferrule, and a metal cylindrical member for forming the base end, wherein the plastic cylindrical member is in contact with the enlarged part of the end of the optical fiber core at the inner peripheral surface of the end side to be secured to the end of the optical fiber core, and the metal cylindrical member is contacted under pressure with the outer periphery of the end of the plastic sheath by a stopper projecting from the inner peripheral surface of the metal cylindrical member so as to be fastened to the plastic sheath.