摘要:
A transmitter is located in a tire of a vehicle and transmits data indicating a tire condition using a carrier wave. The transmitter has an oscillator circuit and a transmission controller. The oscillator circuit generates the carrier wave. The transmission controller compensates a deviation of the amplitude of the carrier wave generated by the oscillator circuit relative to a predetermined reference value such that the amplitude of the carrier becomes equal to the reference value. This is capable of maintaining a constant amplitude of a carrier wave.
摘要:
A transmitter for a tire condition monitoring apparatus includes a pressure sensor for detecting of the internal pressure of a tire, a transmission circuit for generating a transmission signal, and a transmission antenna for transmitting the transmission signal as a radio wave. The transmission antenna is a planar antenna and includes a plate-like transmission conductor for transmitting the radio wave. The transmission antenna is configured such that the radio wave transmitted from the transmission conductor becomes a circularly polarized wave. As a result, the transmitter has a superior transmission performance and a reduced size.
摘要:
A compact and light semiconductor sensor for detecting pressure and acceleration. A pressure sensor is formed on a first surface of an intermediate plate. An acceleration sensor is formed on a second surface of the intermediate plate. A first plate having a diaphragm is bonded to the intermediate plate to define a hermetic chamber of the pressure sensor. A second plate is bonded to the second surface of the intermediate plate. A spring support supports the mass in a manner relatively movable with respect to the second plate.
摘要:
A transmitter is provided in each of tires to wirelessly transmit data representing the condition of the associated tire and data representing the direction of acceleration. A first reception antenna receives data from the transmitters provided in left and right front tires. A second reception antenna receives data from the transmitters provided in left and right rear tires. When receiving data from one of the transmitters, the receiver determines the position of the tire in which the transmitter that is the source of the data is provided based on the levels of received signals each sent from the first reception antenna and the second reception antenna.
摘要:
A tire status monitoring apparatus capable of providing notification of an abnormal status for a tire in accordance with the speed of a vehicle. The tire status monitoring apparatus includes transponders which are provided on the respective tires, detect statuses of the tires in response to a request signal and generate transponder data including data indicative of the statuses of the tires detected, and a transceiver which transmits the request signal to each transponder and receives the transponder data from each transponder. The transceiver determines the number of times the request signal is transmitted per unit time in accordance with the speed of the vehicle.
摘要:
A tire monitoring apparatus includes transponders and a transmitter-receiver. Each transponder is provided in one of the tires of a vehicle, and the transmitter-receiver is mounted on the body frame of the vehicle. In response to a predetermined interrogating radio wave, each transponder detects a condition of the corresponding tire and wirelessly transmits data representing the detected condition of the tire. The transmitter-receiver transmits the interrogating radio wave and receives data wirelessly transmitted by each transponder. In a part of a period during which the corresponding tire rotates through one revolution, each transponder passes through a communication range. The transmitter-receiver changes the time interval at which the interrogating radio wave is transmitted such that the interrogating radio wave is transmitted while the transponder is in the communication zone. As a result, the conditions of the tires are always monitored in a reliable manner.
摘要:
Each of transmitters includes a condition detecting device for detecting the condition of a corresponding tire, and an acceleration detecting device for detecting the direction of acceleration accompanying rotation of the corresponding tire. Each transmitter wirelessly transmits data containing data representing the condition of the tire and data representing the direction of the acceleration. A repeater receives data from the transmitters provided in front tires or data from the transmitters provided in rear tires. When receiving data from any of the transmitters, the repeater wirelessly transmits a response signal when a predetermined period has elapsed after the reception of the data. A receiver receives data from the transmitters and the response signal from the repeater. Based on whether the receiver has received the response signal from the repeater after receiving data from one of the transmitters, the receiver determines the position of the tire in which the transmitter that is the source of the data is provided.
摘要:
A transmitter in an apparatus for monitoring a condition of a tire of a vehicle includes a circuit portion and a casing that accommodates the circuit portion. The casing has a first pressure transmitting portion that transmits the pressure in the tire to the circuit portion so that the circuit portion can detect the pressure in the tire. The pressure transmitted to the circuit portion through the first pressure transmitting portion produces force that presses the circuit portion. The casing further has a second pressure transmitting portion that transmits the pressure in the tire to the circuit portion to apply force that acts against the pressing force to the circuit portion. Therefore, the transmitter prevents a substrate from flexing.
摘要:
A tire air monitoring apparatus includes transmitters for wirelessly transmitting data regarding the inner pressure of tires and a receiver for receiving the data transmitted by the transmitters. Each transmitter is powered by a battery. Each transmitter includes a pressure sensor, which measures the inner pressure of the tire at predetermined measuring intervals. Each transmitter periodically and wirelessly transmits data every time the pressure sensor has taken a measurement a predetermined number of times. When the tire pressure changes by an amount that is equal to or greater than a predetermined upper limit value during a predetermined judging time, the transmitter performs an early data transmission. Therefore, an abnormality in the tire pressure is immediately communicated to a driver, and battery strength is conserved.