JP2011170479A - Alarm device for parking lot gate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an alarm device for a parking lot gate, which can discriminate between a vehicle and a person and issue an alarm corresponding to the discrimination result, is easy to install, and is suitable for a wide parking lot gate. <P>SOLUTION: The alarm device comprises two laser sensors 5 and 6 arranged with a small gap L therebetween at the parking lot gate, a calculation device 3 connected to the laser sensors, and an alarm 4. The calculation device 3 includes: a calculation means 11 which, when light from the laser sensors 5 and 6 is sequentially shielded by passage of a vehicle or a person, calculates a light shielding time difference t between the laser sensors 5 and 6 and a delay time nt being the n times the difference t; and a discrimination means 12 for discriminating between a vehicle and a person in accordance with a light shielding state during the delay time nt. The alarm 4 is provided with a function to issue an alarm corresponding to the discrimination result. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to an alarm device for a parking lot entrance that is installed at a parking lot entrance and detects traffic of a pedestrian or a car and issues a warning to a pedestrian or a driver.

  2. Description of the Related Art An alarm device for a parking lot entrance / exit in which an optical or electromagnetic sensor is installed at the entrance / exit of a parking lot and an alarm is issued by a buzzer, a patrol light or the like when an object is detected is widely used. However, since many of them cannot distinguish between cars and people, they only issue warnings indiscriminately.

  Therefore, as shown in Patent Document 1, two sensors are arranged at a fixed interval, and when both sensors issue detection signals at the same time, it is determined as a car, and when they individually detect detection signals, they are determined as humans. An alarm device for the entrance and exit of a multi-story parking lot has been proposed.

  However, the device of Patent Document 1 has a problem that the installation interval between the two sensors must be about 1 m wider than the width of the human body in order to reliably identify a person and a vehicle, and installation work is troublesome. there were. It is suitable for monitoring a narrow area such as a multilevel parking lot entrance / exit, but not suitable for a wide parking lot entrance such as a large parking lot facing the sidewalk.

Japanese Utility Model Publication No. 5-30961

  The object of the present invention is to solve the above-mentioned conventional problems, distinguish between a car and a person and issue a warning according to each, and the installation work is simple and suitable for a wide parking lot entrance / exit. It is to provide a warning device at the entrance of the parking lot.

  The parking lot entrance / exit alarm device of the present invention, which has been made to solve the above-described problems, includes two laser sensors arranged at a small interval L at the entrance / exit of the parking lot, and an operation connected to these laser sensors. An arithmetic unit comprising a device and an alarm device, when these laser sensors are sequentially shielded by the passage of a car or a person, computes a light shielding time difference t between the laser sensors and a delay time nt that is n times that time. And a discriminating means for discriminating between a car and a person based on a light shielding state during a delay time nt, and the alarm device has a function of issuing an alarm according to the discrimination result.

  Note that, as in claim 2, the determination means may be provided with a function of determining that the vehicle is an automobile when light shielding continues during the delay time nt. According to a third aspect of the present invention, the discriminating means has a function of discriminating between a car and a person based on the integrated value of the light shielding time when the incident light and the light shielding are repeated during the delay time nt. it can. Further, as defined in claim 4, it is preferable that the discriminating means has a function of judging an abnormality when the light is continuously shielded from light for a predetermined time.

  The parking lot doorway alarm device of the present invention calculates a delay time nt that is n times the delay time nt based on a light blocking time difference t between two laser sensors arranged at a small interval L at the parking lot doorway. Since the method of discriminating between the automobile and the person is adopted based on the light-shielding state during nt, the installation interval L of the two laser sensors can be made narrower than the width of the human body, and the light receiving unit can be integrated. It is possible to downsize equipment and simplify installation work.

  Moreover, the parking device entrance / exit warning device of the present invention is capable of discriminating between cars and people and issuing various warnings according to the traveling direction. Furthermore, since the parking device doorway alarm device of the present invention uses a laser sensor, it can cover a section of several tens of meters in width and can be applied to a wide parking lot doorway.

It is a block diagram which shows embodiment of this invention. It is an enlarged view of a reflection type laser detector and a reflector. It is an enlarged view of a light emitting and receiving type laser detector and a reflector. It is a figure which shows a mode when a motor vehicle enters a parking lot. It is a figure which shows a mode when a motor vehicle leaves a parking lot. It is a figure which shows a mode when a person passes. It is a time chart of object discrimination of the present invention. It is a time chart of malfunction prevention.

Preferred embodiments of the present invention are shown below.
FIG. 1 is a block diagram showing an embodiment of the present invention. 1 is a laser detector installed on one side of a parking lot entrance, 2 is a laser beam reflector installed on the opposite side of the entrance, and 3 is a laser. An arithmetic unit 4 connected to the detector 1 is an alarm.

  As shown in FIG. 2, the laser detector 1 includes two laser sensors 5 and 6 arranged with a small interval L inside a self-supporting sensor box. The small interval L can be made narrower than the width of the human body, and is preferably about 10 to 20 cm. The height from the ground is a height that can be reliably detected even when a car with a low vehicle height travels through the entrance of a parking lot. The two laser sensors 5 and 6 are installed in parallel with the traveling direction of the automobile at the entrance / exit of the parking lot.

  In this embodiment, each of the laser sensors 5 and 6 includes a laser projector and a light receiver. The laser beam reflector 2 is also provided with two retro-reflective laser reflectors 7 and 8 arranged with a small interval L inside the self-supporting sensor box. Laser beams projected from the laser sensors 5 and 6 are reflected by the laser reflectors 7 and 8 and received by the laser sensors 5 and 6.

  In addition to such a reflection type, as shown in FIG. 3, the laser sensors 5 and 6 may be dedicated to light reception, and the laser reflection plates 7 and 8 may be replaced with laser projectors 9 and 10 to form a light projection / reception type laser detector. it can.

  In the case of the reflection type of FIG. 2, the maximum distance between the laser detector 1 and the reflector 2 is about 15 m, and in the case of the light projection / reception type of FIG. 3, the maximum distance between the laser detector 1 and the laser projector is about 60 m. can do. In the case of the reflection type in FIG. 2, the distance L between the two laser sensors 5 and 6 is about 10 to 20 cm, and in the case of the light emitting and receiving type in FIG. About 40 cm is preferable. As described above, in any case, the distance L between the two laser sensors 5 and 6 can be narrowed, so that the integrated laser detector 1 can be obtained. The laser detector 1 and the reflector 2 or the laser detector 1 and the laser projectors 9 and 10 may be installed so as to face each other. However, as shown in FIG. This is effective for increasing the detection accuracy.

  The two laser sensors 5 and 6 arranged in this way output a signal to the arithmetic unit 3 when the laser beam is shielded by an automobile or a person. The arithmetic device 3 includes arithmetic means 11, determination means 12, and malfunction prevention means 13. When a car or a person passes through the doorway, the laser sensors 5 and 6 are always shielded sequentially, so that the computing device 3 computes the shielding time difference t. Since the distance L between the laser sensors 5 and 6 is constant, when the speed is V, t = L / V. The traveling direction can be detected depending on which laser sensor 5 or 6 is shielded first.

  Next, the computing device 3 computes a delay time nt that is n times the light shielding time difference t. When L is 20 cm, n is preferably about 6 to 10, and when L is 10 cm, n is preferably about 10 to 20. n is not necessarily an integer. When the front end of the vehicle body traveling at the speed V shields the laser sensors 5 and 6 sequentially, the vehicle travels the distance L during the light shielding time difference t. Therefore, if the speed V is constant, the vehicle should travel a distance nL during the delay time nt. If L = 20 cm and n = 10, it moves 200 cm during the delay time nt regardless of the length of the delay time t.

  When the light shield is an automobile, the length of the vehicle body is 2 m or more, so that the laser sensors 5 and 6 are still shielded from light by the vehicle body even when the tip of the vehicle body moves 200 cm. On the other hand, since the human body has a width of 1 m or less when the light shield is a person, the laser sensors 5 and 6 should receive the laser beam before moving 200 cm. For this reason, the discriminating means 12 discriminates whether it is a car or a person according to the light shielding state during the delay time nt. The advantage of the method of the present invention is that the determination can be made regardless of the passing speed V. Even if the automobile runs at the same low speed as the walking speed of the person, or the person is in front of the laser sensors 5 and 6 at a high speed. Even if you run through, you will not make a mistake.

  The operation of the discriminating means 12 will be described in more detail. First, when light shielding continues during the delay time nt, a car having a continuous vehicle body such as a passenger car or a truck has passed. to decide. However, in a vehicle such as a trailer in which the driver's seat and the loading platform are separated, the position at a distance nL from the front end of the vehicle body becomes a connecting portion, and light incident and light shielding are repeated during the delay time nt. In addition, even if a person is a group of several people, light incident and light shielding are repeated.

  That is, in any of these cases, since the light incident on the laser sensors 5 and 6 and the light shielding are repeated during the delay time nt, the determination unit 12 calculates an integrated value of the intermittent light shielding time. A car and a person are discriminated according to what percentage of the delay time nt the integrated value occupies. Specifically, in the case of an automobile, the light shielding ratio is considered to be 90% or more, and in the case of a person, it is considered to be 60% or less. Therefore, with the intermediate value as a reference, it is determined that the vehicle is a car when the shading ratio is larger than that, and that it is a person when it is small. This situation is shown in the time chart of FIG.

  In this way, when the discriminating means 12 discriminates an automobile entering the parking lot, a signal is sent to the alarm device 4 and, for example, “the vehicle is stopped at a fixed position” from the speaker 15 of the alarm device 4 as shown in FIG. , Please turn off the engine. " When the discriminating means 12 discriminates that the car is leaving the parking lot, the patrol light 14 of the alarm device 4 is turned on as shown in FIG. 5, and a message such as “Care out, please be careful” from the speaker 15, for example. Is output. If the determination means 12 determines that a person has passed, for example, a message “Please pay attention to the car” is output from the speaker 15 of the alarm device 4 as shown in FIG.

  In addition, when a person or a car stops in front of the laser sensors 5 and 6, the function of the present invention cannot be exhibited. Therefore, when the continuous light shielding time is too long, the malfunction prevention means 13 determines that the light is improperly shielded, stops the function, and prevents malfunction. Further, when only one laser sensor is shielded and the other is not shielded, there is a possibility that fallen leaves or the like are stuck. Therefore, it is determined that the shield is illegally shielded, and the function is stopped to prevent malfunction. These states are shown as malfunction prevention in the time chart of FIG.

  As described above, the parking lot doorway alarm device of the present invention of the present invention reduces the size of the equipment and reduces the installation work by making the installation interval L of the two laser sensors 5 and 6 narrower than the width of the human body. There is an advantage that simplification can be achieved, and various warnings can be issued according to the traveling direction by accurately discriminating between a car and a person. Moreover, since the laser sensor is used, it can be applied to a parking lot having a wide entrance and exit.

DESCRIPTION OF SYMBOLS 1 Laser detector 2 Reflector 3 Arithmetic device 4 Alarm device 5 Laser sensor 6 Laser sensor 7 Laser reflector 8 Laser reflector 9 Laser projector 10 Laser projector 11 Calculation means 12 Discriminating means 13 Malfunction prevention means 14 Patrite 15 Speaker

Claims (4)

It consists of two laser sensors arranged at a small interval L at the entrance / exit of the parking lot, an arithmetic unit connected to these laser sensors, and an alarm device,
The arithmetic unit is configured to calculate arithmetic means for calculating a light shielding time difference t between the laser sensors and a delay time nt that is n times greater than the laser sensors when the laser sensors are sequentially shielded by the passage of an automobile or a person, and light shielding during the delay time nt. A discriminating means for discriminating a car and a person according to the state;
An alarm device for a parking lot entrance / exit, wherein the alarm device has a function of issuing an alarm according to a discrimination result.   2. A parking lot entrance / exit warning device according to claim 1, wherein the discriminating means has a function of discriminating an automobile when light shielding continues during the delay time nt.   The discriminating means has a function of discriminating between a car and a person based on an integrated value of the light shielding time when light incident and light shielding are repeated during the delay time nt. Warning device for parking lot entrance.   2. The parking lot entrance alarm device according to claim 1, wherein the discriminating means has a function of judging an abnormality when the light is continuously shielded from light for a predetermined time or more.