Abstract: A signal transponder transceiving signals using different communication protocols has a control module, a receiving module and a transmitting module. The control module is electrically connected to the receiving module and the transmitting module, is built in with multiple communication protocols, decodes a tire pressure signal transmitted from and encoded by an external tire pressure sensor with one of the communication protocols, encodes the decoded information to a new tire pressure signal, and further transmits the new tire pressure signal to a tire pressure receiver. Accordingly, there is no failure in decoding and transmissions and cost increase when the signal transponder communicates with tire pressure sensors and a tire pressure receiver using two different communication protocols.

Abstract: A wireless tire pressure sensing device, a method for setting a standard tire pressure thereof and a wireless tire pressure sensing activation device adjust the tire pressure of each tire in a vehicle to a standard tire pressure according to a requirement of the vehicle after the wireless tire pressure sensing device is mounted in each tire, maintain each tire at the standard tire pressure for a preset time period or employ the wireless tire pressure sensing activation device to transmit a setup instruction to the wireless tire pressure sensing device to set a current tire pressure as the standard tire pressure. The wireless tire pressure sensing device can be set up with the standard tire pressure and conveniently modified. As no threshold value of tire pressure needs to be pre-stored, wireless tire pressure sensing devices with different threshold values are not necessarily prepared beforehand, thereby effectively lowering the stocking pressure on inventory management.

Abstract: A valve stem with an adjustable tire pressure detector has a tire pressure detector, a valve stem body, a conducting member and a fastening assembly. The tire pressure detector has a guiding slot, a concave surface and a convex surface. The guiding slot is formed through the tire pressure detector and forms two openings. The concave surface and the convex surface are formed on the tire pressure detector respectively adjacent to the openings. The valve stem body is moveably mounted through the guiding slot and has a head being moveably mounted on the concave surface. The conducting member is mounted on the concave surface or the convex surface and is electrically contacted to the valve stem body and the tire pressure detector. The fastening assembly mounts the valve stem body on a rim securely.