JPS6031309B2 - Ultrasonic alarm transmitter/receiver configuration - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a wave transmitting/receiving unit configuration of an ultrasonic warning device, and an object thereof is to provide a wave transmitting/receiving unit configuration with good detection sensitivity.

The configuration of the wave transmitting/receiving unit in a conventional ultrasonic warning device is such that a wave transmitting element A and a wave receiving element B are arranged in a plane as shown in Fig. 1. However, in order to detect changes in Doppler frequency, It is sensitive to movements that move away from or approach the warning device D, but it is less sensitive to movements that cross it because it is difficult to detect Doppler changes, and therefore the detection area must be expanded. If an attempt is made to mount the sensor on the ceiling surface, the detection sensitivity will be adversely affected.

Generally, for the movement of a movable body M with respect to a warning device D as shown in Fig. 2, if the speed of sound is c, the transmission frequency is f, and the velocity of the movable body is v, then its Doppler frequency ' is △f= This is something that can be seen in science.For a movable body M that moves across a fence D, as shown in Figure 3, the angle between its line of movement and the centripetal line to the security device M is the same. When, that △r=
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As the ratio increases, the peak becomes smaller, and in the oval detection pattern as shown in FIG. 2, the movable body M immediately goes outside the detection area and is not detected. In view of the above, the present invention is to provide a wave transmitting/receiving section configuration of an ultrasonic warning device that can be attached to a ceiling surface and has good detection sensitivity.

The configuration of the wave transmitting/receiving section of the ultrasonic warning device of the present invention will be explained below with reference to FIGS. 4 to 7 shown as examples. It constitutes a plate block, and a wave transmitting element A and a wave receiving element B are separately mounted in the center between the shade-shaped reflecting plates K, , K2, and K3.

The shade-shaped reflectors K, , K2, and K3 are attached to the ceiling as shown in Figure 4, and are exposed to the floor from between one shade-shaped reflector K and the intermediate shade-shaped reflector K2. Transmitting element A in the direction of plane F
The ultrasonic waves are projected in a tilted shade-like manner, and the reflected waves enter the wave receiving element B between the intermediate shade-shaped reflecting plate K2 and the outer shade-shaped reflecting plate K3. Therefore, as shown in FIGS. 6 and 7, an annular detection area S is formed around the warning device D, so the detection area is expanded, and the movable body M is moved to the floor surface F with respect to this detection area S. When moving above, the angle 8' between the direction of the warning device and the floor F changes, increasing the amount of change in movement in the direction directly facing the warning device D, and increasing the change in Doppler frequency, making it easier to detect. It is. As described above, according to the configuration of the wave transmitting/receiving section of the ultrasonic warning device according to the present invention,
By using a shade-shaped reflector to radiate an ultrasonic radiation pattern consisting of a transmitting element and a receiving element in a shade-shaped manner, it is possible to increase the Doppler frequency change in response to the movement of a movable object across the detector. When installed on the ceiling, movement on the floor can be detected with good sensitivity.

In addition, the transmitting element and receiving element are coaxially arranged at the rough center of the overlapped shade-shaped reflector, which prevents ultrasonic waves from being directly projected from the transmitting element to the receiving element. It also increases the sensitivity of the Doppler frequency), etc.
It is intended to be used as a transmitter/receiver part of an ultrasonic warning device with good sensitivity.

[Brief explanation of the drawing]

Figure 1 is a front view showing the transmitting and receiving part of a conventional ultrasonic warning device.
FIG. 2 is an installation diagram, and FIG. 3 is a diagram showing one detection state. FIG. 4 is a cross-sectional front view showing the structure of the transmitting and receiving part of the ultrasonic warning device of the present invention, FIG. 5 is a perspective view, FIG. 6 is a view showing the detection state, and FIG. 7 is a diagram showing the projection pattern on the floor. FIG. A.
... Wave transmitting element, B... Wave receiving element, K,, K2, K3.
...Shaped reflector. Figure 1 Figure 2 Figure 3 Figure 4 Figure 6 Figure 5 Figure 7

Claims (1)

[Claims] 1. A superstructure characterized by comprising a reflector block in which shade-shaped reflectors are stacked at intervals, and a wave transmitting element and a wave-receiving element are separately mounted at the center between the shade-shaped reflectors. Configuration of the transmitter/receiver section of a sonic alarm.