JPH02196984A - Horn of ultrasonic wave switch - Google Patents

Abstract

PURPOSE:To detect a human body early and to preclude malfunction due to reflection from the irregular surface of the gratings of a folding fan by forming a concave surface part as one internal surface part facing the horn and a concave surface part as the other internal surface part. CONSTITUTION:The horn 1 has a front surface shape which spreads gradually to both sides, one internal surface part of the side wall part facing the horn is formed of the convex surface part 1a and the other internal surface part is formed of the concave surface part 1b. Thus, the right and left parts off the front surface shape of a detection area 11 are not symmetrical about the center of a transmitter receiver 2, so the nonspreading part of the detection area 11 can be directed to the side of the folding fan 9. Consequently, the detection area 11 extends to in front of the folding fan 9 and does not reach the irregular part 9a of the gratings of the folding fan 9, etc. Consequently, the human body 12 can be detected early, there is no misdetection due to the reflection from the rugged part 9a of the folding fan 9, and stable detecting operation is enabled.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a horn for an ultrasonic switch for human body detection in automatic doors and the like.

[Conventional technology]

In reflective ultrasonic switches for human body detection on automatic doors,
Conventionally, the sensor was mounted on the ceiling, but in recent years it has become mainstream to mount the sensor in a blind area for reasons such as installing a shutter just in front of the door.

[Problem to be solved by the invention]

As shown in FIG. 26, a reflective ultrasonic switch 101
When the sensor 102 is attached to the blind part 104 above the door 103, a wide detection area 105 is required because the ultrasonic sensor 102 has a slower detection response than other sensors. However, if the detection area 105 is made too wide, there is a problem that the ultrasonic waves are reflected by the uneven parts 103a such as the grid of the door 103, resulting in malfunction.

That is, the human body 106 that has come toward the door 103 enters the detection area 105 and the ultrasonic switch 101 operates, opening the door 103. However, in order to prevent malfunction, the human body 106 enters the detection area 105. Even if the human body 106 enters the body, it is not determined that the human body 106 has been captured based on one reflected wave. Therefore, in reality, the door 103 does not begin to open at the position of the maximum distance X of the detection area 105, and the door 103 actually
Door 103 begins to open after approaching . Therefore, if the maximum path #X is shortened, the person 106 will collide with the door 103 before the door 103 opens. In order to avoid this, it is necessary to make the maximum path Nx sufficiently large.

However, if the maximum path #X is set large, the sardine sound wave sensor 10
Even if the angle of 2 is changed greatly, the detection area 105 is the same as the door 10.
3, causing malfunction.

An object of the present invention is to provide a horn for an ultrasonic switch that can quickly detect a human body and provide a detection area that can prevent malfunctions due to waves reflected from uneven parts of a door, etc.

[Means to solve the problem]

The horn of the ultrasonic switch of the present invention has one opposing inner surface portion having a convex curved surface and the other inner surface having a concave curved surface.

[Effect]

According to the configuration of the present invention, the detection area spreads asymmetrically, being wider toward the convex curved surface portion of the inner surface of the horn and narrower toward the concave curved surface portion. Therefore, when installing above the door, by orienting the narrower side of the detection area toward the door, it is possible to obtain a detection area that extends widely in front of the door and does not cover the surface of the door.

[Embodiment] An embodiment of the present invention will be described based on FIGS. 1 to 5.

FIG. 1 is a longitudinal sectional front view of the horn, and FIG. 2 is a longitudinal sectional side view. The horn 1 is provided with a fitting cylindrical portion 1c at its base end, into which an ultrasonic transducer 2 consisting of a microphone is fitted. The horn 1 has a front face shape that gradually slopes toward both sides, and one inner surface of opposing side walls is formed into a convex curved surface 1a, and the other inner surface is formed into a concave curved surface 1b. The opening side end positions of the convex curved surface portion 1 a and the concave curved surface portion 1 b are symmetrical to each other with respect to the center line l of the transducer 2 . As shown in FIG. 2, the front and rear inner surfaces 1d and le of the horn 1 are substantially parallel surfaces. The shape of the opening edge If of the horn l is shown in Figure 3 (B
), it is formed into an oblong shape with the front and rear portions flattened.

FIG. 4 is an overall external view of the ultrasonic switch.

The horn l is attached to the front surface of the amplifier housing part 3, and the amplifier housing part 3 is attached to a pair of brackets 5 provided on both sides so as to be movable up and down about a support shaft 6. The bracket 5 projects from the control circuit housing part 4, and the control circuit housing part 4 is provided with a mounting hole 8 through which a fixing screw 7 to the building material is inserted. The control circuit storage section 4 is installed in the blind area 10 above the door 9, as shown in FIG.

According to this configuration, as shown in FIG.
1 spreads toward the convex curved surface part le side of the horn l, and the concave curved surface part lb
The shape does not spread much to the sides.

11a is a boundary on the expanding side of the detection area 11, and llb is a boundary on the non-expanding side. The side shape of the detection area 11 is a shape that spreads symmetrically from front to back as shown in FIG.

In this way, since the front shape of the detection area 11 is asymmetrical in the left and right directions with respect to the center of the transducer 2, the non-expanding side of the detection area 11 can be directed toward the door 9 side, as shown in FIG. can. As a result, the detection area 11 extends far in front of the door 9 and does not overlap the uneven portion 9a of the door 9, such as a grid.

Therefore, the human body 12 can be detected quickly, and the uneven portion 9 of the door 9 can be detected quickly.
．． ! There are no false positives due to reflections, and stable detection can be achieved.

Figures 6 to 8 show a second embodiment, which includes:
The inclination angles of the convex curved surface portion 1a and the concave curved surface portion 1b with respect to the center line i are different from each other, and the distances @wl and w from the center line i of the opening edge if to both ends are different from each other. Eccentricity ratio, that is, distance Mw1. lol.

The ratio can be set freely. The other configurations are similar to the first embodiment. The detection area 1F in this case is as shown in FIGS. 7 and 8. In this way, by changing the eccentricity ratio of the convex curved surface portion 1a and the concave curved surface portion 1b, the degree of eccentricity of the detection area 11' can be changed, making it easier to deal with the installation situation.

In the examples shown in FIGS. 9 to 11, the distance between the opening edges is W3°w4.
are made different from each other, and the ratio of the width W in the longitudinal direction and width 2 in the transverse direction, which is the sum thereof, is made different from the example shown in FIG.

Further, the side shape of the horn 1 is also such that the mouth part widens as shown in FIG. Detection area 11 in this case
' is as shown in FIGS. 10 and 11. In this way, by appropriately combining the aperture shape and eccentricity ratio (ratio of w, w) of the horn 1, even more various detection areas can be formed, making it easier to deal with the installation W1 cane situation.

By preparing the horns 1 of these first to third embodiments, various detection areas can be freely selected.

FIGS. 12 and 13 show a fourth embodiment.

In this example, the length of the fitting part 1c' is increased so that a distance can be obtained between the front surface of the transducer 2 and the front end of the fitting part 1c'.

By varying the distance #h and the diameter φ of the fitting portion 1c', it is possible to stably obtain a biased detection area even if the ambient temperature changes.

FIGS. 14 and 15 show a fifth embodiment.

In this example, an extending portion 1g is provided at the tip of the horn l. By extending the extension portion 1g in this manner, a detection area with a biased shape can be stably obtained even if the ambient temperature changes.

FIG. 16 is an electric circuit diagram of an ultrasonic switch using the horn 1 of this embodiment, and will be explained together with the time chart of FIG. 17. The transmission signal (FIG. 17(A)) applied to the transducer 2 is obtained by amplifying the high frequency signal generated by the light wave circuit 25 with the driver 26. The first monostable circuit 22 sets the rest period of the transmitted signal, and the second monostable circuit 24 sets the application period. The first integrating circuit 21 integrates at the same time as the power is turned on, and drives the first monostable circuit 22 when a certain level is reached. The switching circuit 23 is for discharging the first integrating circuit 21.

The delivery signal of the transducer 2 is amplified by the amplifier circuit 28 (
In FIG. 17(B)), envelope detection is performed by the detection circuit 29.

The amplified transfer signal includes a transfer signal part a of the human body and a transfer signal part A of the floor. Output of the detection circuit 29 (Fig. 17 (C)
)) is determined by the level detection circuit 30 whether it has reached a predetermined detection level L+, and the output when it is 1 or more above the detection level (FIG. 17(E)) is input to the second integration circuit 31. Ru. The second integrating circuit 31 determines whether or not the temporal width of the input signal that has reached the detection level is within a predetermined time width, based on a predetermined level Lt (FIG. 17(F)). In other words, if this time is shorter than the predetermined time width, it is determined that the reflected wave is not a reflected wave from the sensing object but is noise. Further, the second integrating circuit 31 applies a gate signal (FIG. 17(D)) from the gate 27, and also determines whether the input wave is present within a predetermined time. The gate 27 is the first monostable circuit 2
A gate signal (Fig. 17 (
D)) and sends the signal to the second integration circuit 31, which is a time gate that determines the so-called detection distance. The flip-flop 32 stores the signal when the second integrating circuit 31 determines that the input wave has a predetermined time width and is within the gate time (FIG. 17(G)). It is reset by the second monostable circuit 24, and when the reflected wave disappears, it is no longer stored. The third integration circuit 35 integrates the output of the flip-flop 32. This integral output (
In FIG. 17 (H)), if two consecutive reflected waves occur within the gate time, the switching level is L.

It is set to reach . Switching level L3
When the output reaches this level, the second switching circuit 33 turns on the relay 34. The relay 34 turns on and off the power of the door drive motor.

18 to 21 show another example of an ultrasonic switch using the horn 1. This example includes an amplifier housing 3 to which the horn 1 is attached, and a bracket 5' that rotatably supports the horn 1. The detection horn block 60 is configured with the screw 40 that fixes the detection horn block 60 to the control circuit storage part 4
It is attached removably. The amplifier housing 3 and the control circuit housing 4 are connected to cords 41, 42 and connectors 4.
Connect at 3°44. An additional connector 45 is provided in the control circuit housing portion 4 via a cord 46. FIG. 21 is a circuit diagram of the control circuit. The output of the driver 26 is connected to the output terminals of the connector 44 and the expansion connector 45,
The input of the amplifier circuit 28 is connected to the input terminal. 50
is an amplifier circuit in the amplifier storage section 3 of the detection horn block 60, and is connected between the transducer 2 and the amplifier circuit 28. Reference numeral 60' denotes an additional detection horn block, which has the same configuration as the detection horn block 60.

In the case of the second configuration, the detection horn block 60 equipped with the transducer 2 can be freely connected to the control circuit storage section 4, and the connectors 42, 43 and an additional connector 45 are provided, so that the detection Areas can be easily changed.

For example, as shown in FIG.
When the control circuit storage part 4 is installed in the ceiling 61 and the detection horn block 60 is installed in front and behind the door 9 to form the detection area 11 as shown in the figure, the detection horn block 60' is installed in the ceiling 61.
It is possible to add a detection area 63 as shown by a broken line.

Thereby, the human body 12 can be detected from the front side. The additional detection horn block 60' is connected to the control circuit housing 4 by a cord 62. In this case, the relay harness 48 shown in FIG. 19 can be used as the cord 62. If the detection area 11 is not required on the front side of the door 9, only one detection horn block 60 may be removed from the control circuit storage section 4 of the blind section 10 and reinstalled on the ceiling 61.

FIGS. 22 to 25 show still another example of an ultrasonic switch using this horn I. This example is intended to prevent malfunctions due to air faults. To explain the outline, an indoor ultrasonic switch 70 and an outdoor ultrasonic switch 70' are provided in the blind area lO above the door 9, and after the indoor ultrasonic switch 70 detects a human body, the outdoor ultrasonic switch 70 remains open for a certain period of time. This is to reduce the detection ability of the ultrasonic switch 70'.

FIG. 25 shows the circuit diagram of the indoor ultrasonic switch 7.
The timer 72 is operated by the output of the relay 34 when a human body is detected at 0, and the switching circuit 78 provides a signal for reducing the gain of the amplifier circuit 28' of the outdoor ultrasonic switch 70' for the time set in the timer 72. be. The electric circuit of the indoor ultrasonic switch 70 is similar to the example shown in FIG. 16.

The outdoor ultrasonic switch 70' receives the driver input of the transducer 2' from the oscillation circuit 25 of the indoor ultrasonic switch 70. The other electric circuit configuration of the outdoor ultrasonic switch 70' is the same as that of the indoor ultrasonic switch 70, and corresponding parts are given the same reference numerals with a dashed dash.

Indoor ultrasonic switch 70 and outdoor ultrasonic switch 70
′ means parent/child unit. The indoor ultrasonic switch 70 serves as a parent unit, and is provided with a connector 79 (FIG. 23) for connection to an outdoor ultrasonic switch 70' that serves as a child unit.

Before explaining the operation of this example, the problem of human body detection using ultrasonic waves will be explained. By installing air conditioners and refrigeration equipment,
There can be a large temperature difference in the air on both sides of the door. In cold regions, it is often the case that the indoors is warm due to heating and the outdoors is cold, which can lead to the following malfunction problem.

As shown in FIG. 22, an indoor ultrasonic switch 70 and an outdoor ultrasonic switch 70'' are provided in the blind area 10 to detect a human body, and when the door 9 is opened, -1 human body is detected and the door is opened. 9 opens and a person leaves the detection area 11, an air fault 82 is generated between the hot air 80 (Fig. 24) and the cold air 81.The ultrasonic wave is reflected by this air fault 82, and the operating level is slightly lowered. Therefore, the opening time of the door 9 becomes unnecessarily long.

In other words, the door 9 remains open until the hot air 80 and the cold air 81 mix, the temperature difference becomes small, and the reflection from the air fault 82 falls below the operating level. In addition, when the outside is cold and the inside is warm, the reflection of the ultrasonic waves outside is large.
Malfunctions often occur in the ultrasonic switch 70' on the outdoor side.

However, according to the configuration shown in FIG. 25, when the indoor ultrasonic switch 70 detects a human body, the outdoor ultrasonic switch 70 detects a human body.
At 0', the gain of the amplifier circuit 28' is reduced by the time set by the timer 72, and the detection area becomes narrower. In Figure 22, llO indicates a narrowed detection area, so the second
The reflection by the air fault 82 shown in FIG. 4 is not detected, and malfunctions are eliminated.

That is, the door 9 is reliably closed. When the ultrasonic wave is reflected by the air fault 82 and exceeds the operating level as described above, it only exceeds the operating level by a small amount, and it is rare that the operating level is exceeded significantly even in the middle of winter. Therefore, the amplifier circuit 2
There is no need to extremely reduce the gain of 8', and it will not interfere with human body detection. Since the information is obtained from the inner ultrasonic switch 70, there is no problem of interference due to a difference in wave transmission timing between the base unit and the slave unit.

In this example, the detection level outside the room is lowered, but depending on the installation environment, the detection level inside the room may be lowered.
Although the detection level was lowered by lowering the gain of 8′,
The detection level may be lowered by lowering the output of the transmitted wave.

[Effects of the Invention] The horn of the ultrasonic switch of the present invention has one opposing inner surface portion having a convex curved surface portion and the other inner surface portion having a concave curved portion. A narrow detection area can be obtained on the curved surface side.

Therefore, when installed above the door, the detection of a human body is quick and stable operation is achieved without malfunctions due to reflections from uneven surfaces such as the grid of the door.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional front view showing a horn and detection area of an embodiment of the present invention, FIG. 2 is a longitudinal sectional side view thereof, and FIG. 3 (A
) is also an enlarged longitudinal sectional front view of the horn, Figure 3 (B)
is a bottom view of the horn, FIG. 4 is a perspective view of an ultrasonic switch using the horn, FIG. 5 is an explanatory diagram of its operation, and FIG. 6 is a front view of the horn of the second embodiment. 7 is a longitudinal sectional front view showing the detection area, FIG. 8 is a longitudinal sectional side view showing the detection area, and FIG. 9(A) is a longitudinal sectional front view of the third embodiment. B)
10 is a longitudinal sectional front view showing the detection area, FIG. 11 is a longitudinal sectional side view showing the detection area, and FIG. 12 is a longitudinal sectional front view of the fourth embodiment.
3 is a vertical side view of the fifth embodiment, FIG. 14 is a vertical front view of the fifth embodiment, FIG. 15 is a perspective view thereof, and FIG. 16 is an example of an electric circuit of an ultrasonic switch using the horn of this embodiment. A block diagram, FIG. 17 is a waveform diagram, FIG. 18 is a perspective view of another example of an ultrasonic switch using the same horn, FIG. 19 is an exploded perspective view of the same, and FIG. 20 is another example of this horn. 21 is a block diagram of the electric circuit, FIG. 22 is an explanatory diagram of another example of the use of this horn, and FIG. 23 is a perspective view of the indoor ultrasonic switch.
FIG. 24 is an explanatory diagram of its operation, FIG. 25 is a block diagram of its electric circuit, and FIG. 26 is an explanatory diagram of a conventional example. DESCRIPTION OF SYMBOLS 1... Horn, la... Convex curved surface part, lb... Concave curved surface part, 2... Transducer/receiver, 11... Detection area, 3.
...Amplifier storage section, 4...Control circuit storage section, 9...
Door, 12...Human bodyFigure 1Card 2Figure 3Figure 26Figure 10Figure 10','S 14 Leap C,'f 15Figure ( D) Gate circuit output Fig. 17 = 1↑ Fig. 23 Fig. 22 Fig. 24

Claims (1)

[Claims] A horn for an ultrasonic switch in which one opposing inner surface is formed into a convex curved surface and the other inner surface is formed into a concave curved surface.