Vehicle antenna device

Abstract

A vehicle antenna device has a high noise-resistance performance even in high-frequency bands and capable of preventing breakage of a connector due to corotation at the time of fastening / fixing. The vehicle antenna device includes a vehicle exterior antenna and a vehicle interior antenna module. The vehicle interior antenna module includes a circuit board, a module side coaxial connector, a housing and a protecting fixing part. When the vehicle interior antenna module is fastened / fixed to the vehicle exterior antenna through a roof, the protecting fixing part slidably fixes the circuit board to the housing with pressing force that the circuit board is slid where force applied to the module side coaxial connector is larger than a predetermined force if the vehicle exterior antenna and the vehicle interior antenna module corotate due to the fastening and that the circuit board is not slid by vibration of the vehicle.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application is a U.S. national stage application of International Application No. PCT / JP2018 / 031860, filed on Aug. 29, 2018, and claims priority to Japanese Patent Application No. 2017-172009 filed on Sep. 7, 2017.BACKGROUNDTechnical Field[0002]The present invention relates to a vehicle antenna device, and more particularly to a vehicle antenna device including a vehicle exterior antenna and a vehicle interior antenna module.Background Information[0003]As a vehicle antenna device, there is known a roof-mount antenna which is, for example, a low-profile vehicle exterior antenna fixed to the roof of a vehicle. A typical roof-mount antenna is connected to a vehicle interior antenna module through a coaxial connector cable or a relay cable. The vehicle interior antenna module is normally provided in a dashboard. The vehicle interior antenna module has an amplifier circuit and the like and performs various signal processing. The coaxial c...

AI Technical Summary

Benefits of technology

The design achieves high noise resistance and prevents connector breakage during fastening / fixing, maintaining signal integrity even under vibration, by ensuring the connector terminals remain securely aligned and functional.

Problems solved by technology

When the above-mentioned relay cable is used, there may occur loss in a long cable, and, particularly in a vehicle antenna device, a cable is vibrated with vibration of the vehicle to generate noise.

Therefore, the vehicle interior antenna module becomes large and heavy.

Allowance in connector fitting must be avoided since it may cause signal loss or noise.

However, a friction force acting on a screw seat surface during the screw fastening causes corotation of the vehicle exterior antenna and vehicle interior antenna module, which may generate relative rotational displacement.

In this case, when a connector produced with high fitting accuracy is used, the relative displacement of a connector fitting part cannot be structurally absorbed, which may cause cracking of a solder joint part or contact failure at a terminal part due to an external force caused by the rotational displacement.

However, when a connector having the floating structure is used so as to prevent breakage of a connector due to corotation at direct fastening / fixing between the vehicle exterior antenna and the vehicle interior antenna module, structural complications may occur.

Particularly, noise-resistance performance at a high-frequency band of, e.g., 6 GHz, is low, and signal loss in a moving part of a terminal may occur.

A vehicle antenna device is always subject to vibration from a vehicle, so that when a connector having the floating structure is used, noise caused due to vibration cannot be avoided.

Thus, it is difficult to apply a connector having the floating structure to a vehicle antenna device for DSRC.

Images