Keyless entry device having tire pressure monitoring function

• US 20030046993A1
• Filed: 09/11/2002
• Published: 03/13/2003
• Est. Priority Date: 09/13/2001
• Status: Active Grant

• Current Assignee: ALPS Electric Company Limited (Alps Alpine Co., Ltd.)
• Original Assignee: ALPS Electric Company Limited (Alps Alpine Co., Ltd.)
• Inventors: Fujii, Shohei
• Granted Patent: US 7,026,953 B2
• Time in Patent Office: Days
• US Class Current: 73/146.5
• CPC Class Codes: B60C 23/0408 transmitting the signals by non-mechanical means from the wheel or tyre to a vehicle body mounted receiver
• CPC Class Codes: B60C 23/0444 Antenna structures, control or arrangements thereof, e.g. for directional antennas, diversity antenna, antenna multiplexing or antennas integrated in fenders

Abstract

A keyless entry device includes a plurality of antennas which receive high frequency signals, a high frequency receiver which reproduces data from the high frequency signals received by the plurality of antennas, an intermittent controller which changes over an operation of the high frequency receiver between a continuous operation and an intermittent operation in an interlocking manner with turning on or off of an ignition key of an automobile, and a data processor which outputs data as control signals, wherein when the ignition key is turned on, the keyless entry device is operated as the tire pressure monitoring device and when the ignition key is turned off, the keyless entry device is operated as the keyless entry device.

Claims

1. A keyless entry device having a tire pressure monitoring function comprising a portable unit, tire pressure transmitters which are respectively mounted on a plurality of tires and a mainunit, wherein

the mainunit includes a plurality of antennas which receive high frequency signals from the portable unit or the tire pressure transmitters, a high frequency receiver which reproduces data from the high frequency signals received by the plurality of antennas, an intermittent controller which changes over an operation of the high frequency receiver between a continuous operation and an intermittent operation in an interlocking manner with turning on or off of an ignition key of an automobile, and a data processor which outputs the data as control signals,

wherein when the ignition key is turned on, the intermittent controller changes over the operation of the high frequency receiving unit to the continuous operation and the data processor is operated as a tire pressure monitoring device which outputs control signals in response to data from the tire pressure transmitters, and

wherein when the ignition key is turned off, the intermittent controller changes over the operation of the high frequency receiving unit to the intermittent operation and the data processor is operated as a keyless entry device which outputs control signals in response to data from the portable unit.

2. A keyless entry device having a tire pressure monitoring function according to claim 1, wherein the mainunit further includes an antenna changeover part,

wherein when the intermittent controller changes over the operation of the high frequency receiver to the continuous operation, the intermittent controller simultaneously changes over an operation of the antenna changeover part to an operation in which supply of high frequency signals to the high frequency receiver from a plurality of respective antennas is periodically changed over, and

wherein when the intermittent controller changes over the high frequency receiver to the intermittent operation, the intermittent controller simultaneously changes over the operation of the antenna changeover part to an operation in which supply of high frequency signals to the high frequency receiver from the plurality of antennas is intermittently turned on in synchronism with the intermittent operation of the high frequency receiver.