JPH07260927A - Transmission device for vehicle - Google Patents

Abstract

PURPOSE:To change an allowable transmission distance whenever necessary, avoid useless power consumption and restrain the occurrence of unnecessary detection by providing an output change means for increasing transmission output according to an increase in the speed of an own vehicle. CONSTITUTION:A transmission output control section 10 determines transmission output corresponding to a vehicle speed, according to a detection signal from a vehicle speed sensor 9, and sends a corresponding instruction signal to a final stage amplifier 7. This amplifier 7 amplifies a signal from an excited amplifier 6, up to transmission output instructed by the section 10, and the amplified signal is transmitted from an antenna 8. In other words, the section 10 keeps the transmission output at zero level until a vehicle speed reaches, for example, 10 km/h and thereafter incrementally enlarges the output for every speed increase of 10km/h. As a result, the transmission output increases, when the speed of an own vehicle is high and, therefore, the own vehicle can be made to be detected at a large distance from other vehicles. On the contrary, the transmission output is small, when the speed of the own vehicle is low. Unnecessary detection can be thereby prevented and useless electric power consumption can be avoided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle transmitter for informing another vehicle or the like of the presence of a vehicle by transmitting a signal in a predetermined frequency band.

[0002]

2. Description of the Related Art Conventionally, as shown in, for example, Japanese Patent Laid-Open No. 2-216600, a transmission device capable of transmitting an alarm radio wave over which a moving body such as a motorcycle has a radius of 20 to 40 m is mounted. There is known an example in which a receiving device mounted on the other vehicle receives a radio wave transmitted from the transmitting device and can detect the presence of a moving object within a certain area.

[0003]

As described above, in the conventional transmitter, the range of radio waves is limited to within a certain distance, and therefore, under any circumstances, the vehicles of the other party will not come unless the vehicles approach each other within a certain distance. Can not be detected.
However, when the relative speed between vehicles is fast, it is necessary to detect the other vehicle as soon as possible in order to secure sufficient braking time in an emergency. It is not necessary to detect at a long distance.

If the transmittable distance is always set to a large constant value on the assumption that the relative speed is high, the own vehicle will be detected by a long distance vehicle having a small relative speed and not necessary at all. On the contrary, it is bothersome and consumes unnecessary power. The present invention has been made in view of the above points, and an object of the present invention is to provide a vehicular transmission device capable of changing the transmittable distance as necessary.

[0005]

In order to achieve the above-mentioned object, the present invention provides a vehicle transmitting device for informing another vehicle or the like of the presence of the own vehicle by transmitting a signal in a predetermined frequency band. The vehicle transmission device includes vehicle speed detection means for detecting the vehicle speed of the vehicle and output changing means for increasing the transmission output as the vehicle speed detected by the vehicle speed detection means increases.

When the vehicle speed of the host vehicle is high, the transmission output also increases, so that the host vehicle can be detected when the vehicle is far from the other vehicle. Conversely, when the vehicle speed of the host vehicle is slow, It is possible to detect the own vehicle at an appropriate distance with a small transmission output and without unnecessary detection and without wasting power.

When the speed of the host vehicle is equal to or lower than the predetermined speed, the transmission is stopped so that unnecessary transmission to an extremely short distance is not performed and power is not wastefully consumed.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention shown in FIGS. 1 to 4 will be described below. FIG. 1 is a block diagram showing the configuration of the transmission device 1 of this embodiment. The oscillator 2 used here is a crystal oscillator with high frequency stability, and the output of the oscillator 2 is frequency-multiplied by a buffer amplifier 3 so as not to affect the oscillator 2 itself and input to a frequency mixer 4. The signal is combined with the signal synthesized by the PLL synthesizer 5, input to the excitation amplifier 6, amplified, and further input to the final stage amplifier 7 of the next stage.

On the other hand, the detection signal from the vehicle speed sensor 9 for detecting the vehicle speed of the vehicle in which the transmission device 1 is mounted is input to the transmission output control unit 10 to determine the transmission output according to the vehicle speed, and the instruction signal thereof is given. Is input to the final stage amplifier 7. The final stage amplifier 7 amplifies the signal from the excitation amplifier 6 to the transmission output instructed by the transmission output control unit 10 and transmits it from the antenna 8. In addition to controlling the voltage of the final stage amplifier 7, an attenuator may be interposed between the final stage amplifier 7 and the antenna 8 to control the resistance of the attenuator to change the transmission output.

The transmission output control unit 10 controls the transmission output as shown in FIG. That is, the transmission output is set to zero until the vehicle speed reaches 10 km / h, and the transmission output is sequentially increased every time the vehicle speed increases by 10 km / h, and the transmission output is increased stepwise. Therefore, for example, the motorcycle 20 equipped with the transmission device 1 has a different transmittable distance depending on the vehicle speed as shown in FIG. Concentric arcs centering on the motorcycle 20 indicate the transmittable distance for each vehicle speed, and the higher the vehicle speed, the longer the transmittable distance.

A motorcycle equipped with the transmitter 1 now
An actual application example for 20 is shown in FIG. This is an example of a car accident that often happens when a motor vehicle 30 goes from a side road 31 to a main road.
This is the case where the motorcycle 20 is traveling on the main road to the place where it is about to enter 32 and is trying to approach the side road 31.

When the motorcycle 20 is traveling at a vehicle speed of about 30 km / h, it is considerably four-wheeled vehicle 30 as shown in FIG. 4 (1).
Even if the motorcycle 30 receives the signal transmitted from the motorcycle 20 when approaching the vehicle, a sufficient margin can be provided to perform an operation such as braking, and the vehicle further travels at a speed of about 30 km / h. It is not necessary to be able to transmit up to the contrary, but on the contrary, if the transmission capability is high even at a low speed, an extra signal will be received up to a vehicle far away that has no influence at all and it will be annoying and the importance of the detection signal will decrease, It also consumes wasted power.

On the other hand, when the motorcycle 20 is traveling at 60 km / h, the transmission signal can be received by the automobile 30 at a considerable distance from the automobile 30 as shown in FIG. 4 (2). By increasing the transmission output like this, it is possible to give sufficient margin to perform operations such as braking, and even if the occupant of the motorcycle 30 directly sees the motorcycle 20, the vehicle speed is actually You can reduce the chances of misreading lower.

In various other cases, by increasing the transmittable distance according to the vehicle speed, a vehicle within a distance that is required to be detected without causing other vehicles to perform unnecessary detection and causing trouble. Can be surely sent. In addition, since it is not necessary to transmit to a very close distance where normal view can be entered and braking is easily performed, in this embodiment, when the vehicle speed is 10 km / h or less, the transmission is stopped to suppress unnecessary power consumption.

Although the transmission device of this embodiment has the transmission output characteristic as shown in FIG. 2 which shows the change of the transmission output with respect to the vehicle speed, the transmission output characteristic should be changed to the most suitable one depending on the type of the vehicle to be mounted. To do.

[0016]

According to the present invention, since the transmission output also increases when the vehicle speed of the host vehicle is high, the host vehicle can be detected when the vehicle is far from the other vehicle, and the braking time can be shortened in an emergency. When the vehicle speed of the host vehicle is slow, the transmission output is small so that unnecessary detection is not performed and the own vehicle is detected at an appropriate distance without wasting power. You can

When the speed of the host vehicle is equal to or lower than the predetermined speed, the transmission is stopped so that unnecessary transmission to an extremely short distance is not performed and power is not wastefully consumed.

[Brief description of drawings]

FIG. 1 is a schematic block diagram showing a configuration of a transmission device according to an embodiment of the present invention.

FIG. 2 is a diagram showing a transmission output characteristic with respect to a vehicle speed by a transmission output control unit in the transmission device.

FIG. 3 is a diagram showing how the transmittable distance changes according to the vehicle speed of a motorcycle equipped with the same transmission device.

FIG. 4 is a diagram showing an actual application example of a motorcycle equipped with the same transmission device.

[Explanation of symbols]

1 ... Transmitting device, 2 ... Oscillator, 3 ... Buffer amplifier, 4 ... Frequency mixer, 5 ... PLL synthesizer, 6 ... Excitation amplifier, 7
… Final amplifier, 8… Antenna, 9… Vehicle speed sensor, 10…
Transmission output control unit, 20 ... motorcycle, 30 ... motorcycle, 31
… Side road, 32… main road.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display part H04B 1/04 A

Claims (2)

[Claims] 1. A vehicle transmission device for informing another vehicle or the like of the existence of a vehicle by transmitting a signal in a predetermined frequency band, the vehicle speed detecting means for detecting a vehicle speed of the own vehicle, and the vehicle speed detecting means for detecting the vehicle speed. A transmission device for a vehicle, comprising: an output changing unit that increases a transmission output as a vehicle speed increases. 2. The output changing means stops transmission by setting the transmission output to zero when the vehicle speed detected by the vehicle speed detecting means is equal to or lower than a predetermined speed including the stopped state, and when the vehicle speed is equal to or higher than the predetermined speed, the transmission output increases as the vehicle speed increases. The vehicle transmission device according to claim 1, wherein: