Patent ID: 7187272

Claim:
A transmitter in an apparatus for monitoring a condition of a tire attached to a wheel of a vehicle, wherein the transmitter is fixed to the wheel such that the transmitter faces an outer circumferential surface of a wheel rim, the transmitter comprising: a circuit portion that detects the condition of the tire and generates a transmission signal that contains data representing the detected condition of the tire; a casing that accommodates the circuit portion; and a leg that extends from the casing toward the outer circumferential surface of the wheel rim, wherein the extended amount of the leg is adjustable such that the leg contacts the outer circumferential surface of the wheel rim when the transmitter is fixed to the wheel, wherein the leg includes an attachment that is detachably attached to the casing, and wherein the attachment is selected from a plurality of attachments that are prepared in advance according to variations in the size and the shape of the wheel, wherein an engagement mechanism for engaging the attachment with the casing is located between the casing and the attachment.