Abstract: A transmitting and receiving circuit may include a first CMOS inverter configured to receive a first power supply signal and a first input signal. The transmitting and receiving circuit may include a first calculation amplifier including a non-inverted input terminal connected to an output terminal of the first CMOS inverter, and a first resistor connected between the output terminal of the first calculation amplifier and a first node. The output terminal of the first calculation amplifier and an inverted input terminal of the first calculation amplifier may be connected to each other. A first output signal may have a level smaller than that of the first input signal and may be output to the first node.

Abstract: An air-bed for a vehicle has a front seat on which an air-bed filled with air can be formed after a back of the front seat is reclined rearward, thereby providing a comfortable, easy rest space during a long distance tour or auto camping. An air-bed for a vehicle can be used in the vehicle during a long distance tour or auto camping. The air-bed for the vehicle is designed to provide a full level plane and to thereby provide comfortable rest without muscle pain that may be caused by protruded portions formed by unevenness of front and rear seats.

Abstract: A foldable bed for a vehicle, and more particularly a foldable bed for a vehicle which can be folded for storage in a trunk and unfolded for installation in the vehicle in case of necessity. It is an object of the invention to provide a foldable bed for a vehicle which can utilize spaces in the passenger's seat and back side of seats to serve for a rest in case of tiredness and to easily evacuate an emergent patient.