WO2007029636A1

WO2007029636A1 - Intrusion detecting sensor

Info

Publication number: WO2007029636A1
Application number: PCT/JP2006/317437
Authority: WO
Inventors: Masatoshi Tsuji
Original assignee: Optex Co., Ltd.
Priority date: 2005-09-09
Filing date: 2006-09-04
Publication date: 2007-03-15
Also published as: JP2007071829A

Abstract

An intrusion detecting sensor, in one example, is provided with a microwave sensor (1) which transmits a microwave toward a detection area, receives the reflection wave of the microwave from an object existing within the detection area and judges whether the object is a detection target object or not; a heat generating means (3) which generates heat; and a heat insulating material (M1) which surrounds the microwave sensor (1) and the heat generating means (3) and almost entirely covers an inner plane of a case (2).

Description

Specification

Intrusion detection sensor

Technical field

TECHNICAL FIELD [0001] The present invention relates to an intrusion detection sensor incorporating a microwave sensor or an infrared sensor, and particularly relates to an intrusion detection sensor suitable for outdoor installation in a cold region.

[0002] Intrusion detection sensors such as microwave sensors and surveillance cameras are often installed outdoors. The ambient temperature can vary greatly depending on the region and season in which they are used. For example, in the winter in extremely cold regions, the ambient temperature may be well below freezing.

[0003] The various electronic components used in these intrusion detection sensors and surveillance cameras have their operating temperature ranges guaranteed for their functions and performance. The temperature is often! /, Often 20 ° C!

[0004] Therefore, in order to operate the intrusion detection sensor, the surveillance camera, etc. normally even in an environment where the ambient temperature can be lower than that, for example, a heat source such as a heater is arranged inside, or external force is directly or and and supplies the indirect heat, it is necessary to perform thermal insulation (for example, Patent Document 1, Patent Document 2.) ₀

Patent Document 1: Japanese Patent Laid-Open No. 2005-94545

Patent Document 2: JP-A-7-107348

Disclosure of the invention

Problems to be solved by the invention

[0005] Even if the interior is simply warmed with a heater, etc., the heat is likely to be radiated to the outside through the housing, so the temperature inside the housing will rise sufficiently, especially when the outside air temperature is extremely low There were also things that I couldn't let you do.

[0006] Although it is conceivable to use a heater that generates a large amount of heat by predicting the amount of heat radiated to the outside in advance, there is a problem that power consumption increases. [0007] In order to reduce heat radiation to the outside, it is also conceivable to arrange a heat insulating material on the inner surface of the housing. In order to obtain a sufficient heat retention effect in this case, it is necessary to cover the entire inner surface of the housing with a heat insulating material without any gaps. However, if it is a surveillance camera, the optical path to the taking lens must be kept at a minimum. In the case of an intrusion detection sensor that uses microwaves, if there is any obstruction on the front of the antenna, the detection sensitivity will decrease, so it is necessary to leave that part open. For this reason, in practice, a large gap remained, and it was difficult to obtain a sufficient heat retention effect.

[0008] In view of such problems of the prior art, the object of the present invention is to operate normally without degrading the detection performance even under conditions where the ambient temperature is extremely low, with a simple and inexpensive configuration. Is to provide a simple intrusion detection sensor.

Means for solving the problem

[0009] The intrusion detection sensor of the present invention transmits a microwave toward a detection area, receives a reflected wave of the microwave of the object force existing in the detection area, and the object is a detection target object. A microwave sensor for determining whether or not, a heat generating means for generating heat, and a heat insulating material that surrounds the microwave sensor and the heat generating means and covers almost all of the inner surface of the housing It is characterized by that.

[0010] Here, as the heat insulating material, a material having a relative permittivity ε r = 1 and hardly affecting the microwave is used. Specifically, the force includes a foam material such as polystyrene foam, but is not limited thereto.

[0011] According to the intrusion detection sensor having such a configuration, the microwave sensor forms a detection area having the same detection sensitivity as that in a normal case. Only a small amount of heat generated by the heat generating means is radiated to the outside through the housing, and efficient heat insulation can be performed. This makes it possible to realize an intrusion detection sensor that operates properly even under conditions where the ambient temperature is extremely low while maintaining sufficient detection sensitivity in an intrusion detection sensor incorporating a microwave sensor. .

[0012] In addition, in the intrusion detection sensor of the present invention, at least a portion of the heat insulating material on a microwave path transmitted and received by the microwave sensor has a relative dielectric constant of approximately 1 and is almost equal to the microwave. You may use the material which does not affect. In this case However, any other material can be used for other parts.

[0013] According to the intrusion detection sensor having such a configuration, the degree of freedom in selecting a heat insulating material to be used in a portion other than the microwave path is expanded, so that the intrusion detection sensor can be reduced in size and cost. it can.

[0014] Alternatively, the intrusion detection sensor of the present invention receives infrared rays from the detection area and determines whether or not there is an object to be detected in the detection area based on a temperature difference from the surrounding area. A heat generating means for generating heat, and a heat insulating material that surrounds the passive infrared sensor and the heat generating means and covers almost all of the inner surface of the housing. It is a feature that a through-hole through which infrared rays pass is formed in the part of the infrared ray path to the type infrared sensor.

[0015] According to the intrusion detection sensor having such a configuration, only a small amount of the heat generated by the heat generating means is radiated to the outside through the housing, and efficient heat insulation can be performed. This makes it possible to realize an intrusion detection sensor that operates normally even under conditions where the ambient temperature is extremely low in an intrusion detection sensor incorporating a passive infrared sensor.

[0016] Alternatively, the intrusion detection sensor of the present invention transmits a microwave toward a detection area, receives a reflected wave of the microwave from an object existing in the detection area, and the object is A microwave sensor that determines whether or not the force is a detection target object and infrared rays from within the detection area, and the presence or absence of a detection target object in the detection area is determined based on a temperature difference from the surroundings. Surrounds the passive infrared sensor, the heat generating means for generating heat, and the microwave sensor, the passive infrared sensor and the heat generating means.

And a heat insulating material covering almost all of the inner surface of the housing, and at least a portion of the heat insulating material on a microwave path transmitted and received by the microwave sensor has a relative dielectric constant of approximately 1. A material that hardly affects the microwave is used, and a through hole that allows infrared rays to pass through is formed in a portion of the heat insulating material on the infrared path to the passive infrared sensor. It is characterized by that.

[0017] According to the intrusion detection sensor having such a configuration, only a small amount of heat generated by the heat generating means is radiated to the outside through the housing, and efficient heat insulation can be performed. . As a result, intrusion detection sensors with built-in microwave sensors and passive infrared sensors can achieve intrusion detection sensors that operate normally even under conditions where the ambient temperature is extremely low while maintaining sufficient detection sensitivity. Is possible.

The invention's effect

[0018] According to the intrusion detection sensor of the present invention, in the intrusion detection sensor incorporating a microwave sensor or a passive infrared sensor, the ambient temperature is extremely low while maintaining sufficient detection sensitivity. However, an intrusion detection sensor that operates normally can be realized.

Brief Description of Drawings

FIG. 1 is a cross-sectional view showing a schematic configuration of an intrusion detection sensor according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a schematic configuration of an intrusion detection sensor according to a second embodiment of the present invention.

FIG. 3 is a cross-sectional view showing a schematic configuration of an intrusion detection sensor according to a third embodiment of the present invention.

FIG. 4 is a cross-sectional view showing a schematic configuration of an intrusion detection sensor according to a fourth embodiment of the present invention.

Explanation of symbols

[0020] 10 Intrusion detection sensor (first embodiment)

20 Intrusion detection sensor (second embodiment)

30 Intrusion detection sensor (Third embodiment)

40 Intrusion detection sensor (4th embodiment)

1 Microwave sensor

la Antenna section

2 Enclosure

3 Heater

4 PIR sensor

4a Pyroelectric element 6 Through hole

A1 detection area

A4 detection area

Ml Insulation (Styrofoam)

M2 insulation

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0022] <First embodiment>

FIG. 1 is a cross-sectional view showing a schematic configuration of an intrusion detection sensor 10 according to the first embodiment of the present invention. As shown in FIG. 1, the intrusion detection sensor 10 has a box-shaped housing 2, and the microwave sensor 1 is arranged at the approximate center inside the housing 2. An antenna section la for transmitting and receiving microwaves is arranged on the front side (right side in FIG. 1) of the microphone mouth wave sensor 1, and the inside of the intrusion detection sensor 10 is placed on the back side of the microwave sensor 1. A heater 3 that generates heat when energized is installed in order to maintain heat.

[0023] The microwave sensor 1 is a type that transmits and receives microwaves of two different frequencies. Microwaves are transmitted from the antenna unit la to the detection area A1, and the transmitted microwaves are reflected when any object is present in the detection area A1. Part of the reflected microwave is received back in the direction of the antenna unit la. Then, the microwave sensor 1 detects the phase difference between the two IF signals based on the received reflected waves, and based on this phase difference, the detected object is an original detection target object such as an intruder. The presence / absence (in other words, the presence / absence of the object to be detected) and the distance to the object are detected.

However, the microwave sensor 1 is not limited to transmitting and receiving microwaves having two different frequencies. For example, it may be one that transmits / receives microwaves of three or more different frequencies, or only one that detects the presence / absence of an object to be detected using only a single frequency microwave. .

[0025] All the inner surfaces of the housing 2 of the intrusion detection sensor 10 have a thickness of a predetermined value or more. Heat material Ml is placed in close contact. In FIG. 1, the force shown in the case where a plate-like heat insulating material is attached to each surface of the inner surface of the housing 2 is not limited to this. Also, there may be a slight gap between the insulating materials.

[0026] Insulating materials generally include foamed materials, glass fibers, acrylic materials, aluminum materials, wood, etc. The insulating material Ml used in this intrusion detection sensor 10 has a relative dielectric constant ε r ^ l. Use materials that have little effect on microwaves. Specific examples include the strength of foamed materials such as polystyrene foam. /.

[0027] Although the casing 2 does not need to have heat insulation properties, it is necessary to use a material that hardly affects the microwave.

[0028] According to the configuration of the first embodiment described above, the microwaves transmitted and received by the antenna part la of the microwave sensor 1 are hardly affected by the presence of the heat insulating material Ml in front of the antenna part la. Therefore, a detection area A1 having the same detection sensitivity as that in the normal case is formed. On the other hand, since the heat insulating material Ml is arranged on the inner surface of the housing 2 with almost no gap, only a small amount of the heat generated from the heater 3 is radiated to the outside through the housing 2 with less power consumption. Efficient heat insulation can be performed. As a result, an intrusion detection sensor with a built-in microwave sensor can achieve an intrusion detection sensor that operates normally even under conditions where the ambient temperature is extremely low while maintaining sufficient detection sensitivity. It becomes. In addition, since the structure is simple, it is easy to design and manufacture, and since heat insulating materials and the like can be obtained at a low price, the intrusion detection sensor as a whole can suppress an increase in cost.

[0029] It should be noted that, in order to always maintain the optimum temperature regardless of the ambient temperature, a temperature sensor is further incorporated, and the amount of heat generated from the heater 3 is appropriately controlled according to the detection result of the temperature sensor. It may be configured as ヽ.

[0030] <Second Embodiment>

FIG. 2 is a sectional view showing a schematic configuration of the intrusion detection sensor 20 according to the second embodiment of the present invention. The same components as those in the first embodiment described above are denoted by the same reference numerals, and differences from the first embodiment will be mainly described below.

[0031] As shown in Fig. 2, in this intrusion detection sensor 20, two types of heat insulating material M are provided on the inner surface of the housing 2. 1 and heat insulating material M2 are used in close contact. Specifically, the heat insulating material M 1 that hardly affects the microwave is disposed only in the front direction of the antenna portion la as in the first embodiment, and other types of heat insulating materials M 2 are disposed other than that. RU

[0032] Since there is no restriction on the presence or absence of an influence on the microwave in the heat insulating material M2, it is possible to select a material from the viewpoint of the heat insulating effect and cost. For example, if a material having a high heat insulating effect is used, the heat insulating material can be made thin, so that the intrusion detection sensor 20 as a whole can be miniaturized.

[0033] According to the configuration of the second embodiment described above, the microwaves transmitted and received by the antenna unit la of the microwave sensor 1 are hardly affected by the presence of the heat insulating material Ml in front of the antenna unit la. Therefore, a detection area A1 having the same detection sensitivity as that in the normal case is formed. On the other hand, the heat insulating material Ml or the heat insulating material M 2 is arranged on the inner surface of the housing 2 with almost no gap, so that only a small amount of the heat generated from the heater 3 is radiated to the outside through the housing 2. Efficient heat insulation can be performed with less power consumption. This makes it possible to realize an intrusion detection sensor that operates normally even under conditions where the ambient temperature becomes extremely low while maintaining sufficient detection sensitivity in the intrusion detection sensor incorporating the microwave sensor. Furthermore, since the degree of freedom in selecting a heat insulating material other than the front surface of the antenna portion la is increased, the intrusion detection sensor 20 can be reduced in size and cost.

[0034] <Third embodiment>

FIG. 3 is a cross-sectional view showing a schematic configuration of the intrusion detection sensor 30 according to the third embodiment of the present invention. Note that the same reference numerals are given to the same constituent members as those in the above-described embodiments, and differences from the first embodiment will be mainly described below.

As shown in FIG. 3, in the intrusion detection sensor 30, a passive infrared sensor (hereinafter referred to as “PIR sensor”) 4 is arranged at the approximate center inside the housing 2. On the front side (right side in FIG. 3), a pyroelectric element 4a that receives infrared rays from a human body or the like is arranged. The PIR sensor 4 receives infrared rays from the detection area A4 by the pyroelectric element unit 4a, and detects the presence or absence of a detection target object such as a human body based on a temperature difference from the surroundings.

[0036] The heat insulating material Ml on the front surface of the pyroelectric element section 4a is necessary to secure an infrared optical path. A minimum through hole 6 is formed, and an opening is formed in a portion corresponding to the through hole 6 in the housing 2, and the lens 5 is arranged there. Infrared rays from the human body existing in the detection area A4 are refracted by the lens 5 and reach the pyroelectric element 4a.

[0037] In the intrusion detection sensor 30, there is no particular restriction on the material of the heat insulating material, so the heat insulating effect may be selected based on cost or the like.

[0038] According to the configuration of the third embodiment described above, since the heat insulating material is disposed on the inner surface of the casing 2 with almost no gap except for the through-hole 6, the casing of the heat generated from the heater 3 is disposed. Only a small amount of radiation is emitted through the body 2 to the outside, and efficient heat insulation can be performed with low power consumption. As a result, an intrusion detection sensor with a built-in PIR sensor can be realized that operates normally even under conditions where the ambient temperature is extremely low.

[0039] Such a configuration is not limited to an intrusion detection sensor with a built-in PIR sensor, but is also suitable for an intrusion detection sensor with a built-in active infrared sensor (AIR sensor), for example. In addition to the infrared light receiving element, AIR also includes an infrared light emitting element. By detecting the reflected light from objects in the infrared detection area generated by this infrared light emitting element force, the human body, etc. The presence or absence is detected.

[0040] <Fourth embodiment>

FIG. 4 is a cross-sectional view showing a schematic configuration of an intrusion detection sensor 40 according to the fourth embodiment of the present invention. Note that the same reference numerals are assigned to the same constituent members as those of the above-described embodiments, and differences from the first embodiment and the third embodiment will be mainly described below.

[0041] As shown in FIG. 4, in this intrusion detection sensor 40, the microwave sensor 1 and the PIR sensor 4 are arranged together in the center of the inside of the housing 2 (for example, the microphone mouth wave sensor on the front side of this figure). 1. PIR sensor 4 is placed adjacent to the back side. This is also called a combination sensor (or a combined sensor). By issuing a warning signal only when both the microwave sensor 1 and the PIR sensor 4 detect a detection target object such as a human body, It is intended to increase the reliability of operation by preventing false alarms as much as possible. [0042] On the front side of the microwave sensor 1 (right side in Fig. 4), an antenna unit la for transmitting and receiving microwaves is arranged, and on the front side of the PIR sensor 4 (right side in Fig. 4) A pyroelectric element unit 4a for receiving infrared rays from the human body is disposed. A heater 3 that generates heat for keeping the inside of the intrusion detection sensor 10 is attached to the back side.

[0043] A heat insulating material Ml made of a material that hardly affects microwaves is disposed in close contact with the inner surface of the housing 2 and the heat insulating material Ml on the front surface of the pyroelectric element portion 4a As in the case of the third embodiment, the minimum through-hole 6 required to secure the infrared optical path is formed. Further, an opening is formed in a portion of the housing 2 corresponding to the through hole 6, and the lens 5 is disposed there.

[0044] According to the configuration of the fourth embodiment described above, the microwaves transmitted / received by the antenna unit la of the microwave sensor 1 are hardly affected by the presence of the heat insulating material Ml in front of the antenna unit la. Therefore, a detection area A1 having the same detection sensitivity as that in the normal case is formed. Infrared rays from a human body or the like existing in the detection area A4 are refracted by the lens 5 and reach the pyroelectric element unit 4a. Since the heat insulating material is arranged on the inner surface of the case 2 with almost no gap except for the through holes 6, only a small amount of the heat generated from the heater 3 is radiated to the outside through the case 2 and consumes less power. Can be used for efficient heat insulation. As a result, intrusion detection sensors with built-in microwave sensors and PIR sensors can achieve intrusion detection sensors that operate normally even under conditions where the ambient temperature is extremely low while maintaining sufficient detection sensitivity. It becomes.

[0045] As in the second embodiment, the heat insulating material Ml that hardly affects the microwaves is disposed only in the front direction of the antenna unit la, and other types of heat insulating materials M2 are disposed. Do it.

[0046] The present invention can be implemented in various other forms without departing from the gist or main characteristic power thereof. Therefore, the above-described embodiment is merely an example in all respects and should not be interpreted in a limited manner. The scope of the present invention is indicated by the claims, and is not restricted by the text of the specification. Further, all modifications and changes belonging to the equivalent scope of the claims are within the scope of the present invention. [0047] This application claims priority based on Japanese Patent Application No. 2005-262194 filed on September 9, 2005 in Japan. The contents of which are hereby incorporated by reference into this application. In addition, all references cited in this specification are specifically incorporated by reference.

Industrial applicability

The present invention is suitable for a security sensor that detects an intruder into a detection area and issues an alarm.

Claims

The scope of the claims

[1] A microwave is transmitted to the detection area, and the reflected wave of the microwave from the object existing in the detection area is received to determine whether or not the object is a detection target object. A microwave sensor,

Heating means for generating heat;

A heat insulating material that surrounds these microwave sensors and heating means and covers almost all of the inner surface of the housing

An intrusion detection sensor comprising:

[2] In the intrusion detection sensor according to claim 1,

An intrusion detection sensor characterized in that the heat insulating material is a material having a relative dielectric constant of approximately 1 and hardly affecting microwaves.

[3] In the intrusion detection sensor according to claim 2,

The insulative detection sensor, wherein the heat insulating material is a polystyrene foam.

[4] In the intrusion detection sensor according to claim 1,

At least a portion of the heat insulating material on the microwave path transmitted and received by the microwave sensor is made of a material having a relative dielectric constant of about 1 and hardly affecting the microwave. Intrusion detection sensor.

[5] In the intrusion detection sensor according to claim 4,

An intrusion detection sensor using foamed polystyrene in at least a portion of the heat insulating material on a microwave path transmitted and received by the microwave sensor.

[6] A passive infrared sensor that receives an infrared ray from within the detection area and determines the presence or absence of an object to be detected in the detection area based on a temperature difference from the surroundings.

Heating means for generating heat;

Insulation that surrounds these passive infrared sensors and heating means, and covers almost all of the inner surface of the housing

With

An intrusion detection sensor characterized in that a through hole through which an infrared ray passes is formed in a portion of the heat insulating material on the infrared path to the passive infrared sensor. Microwave that transmits microwaves toward the detection area, receives the reflected waves of the microwaves from the objects existing in the detection area, and determines whether the object is a detection target object A sensor,

A passive infrared sensor that receives infrared rays from the detection area and determines the presence / absence of an object to be detected in the detection area based on a temperature difference from the surroundings;

Heating means for generating heat;

Surrounding these microwave sensors, passive infrared sensors, and heating means, and a heat insulating material covering almost all of the inner surface of the housing

With

At least a portion of the heat insulating material on the microwave path transmitted and received by the microwave sensor uses a material having a relative dielectric constant of approximately 1 and hardly affecting the microwave.

A penetration hole through which an infrared ray passes is formed in a part on the infrared path to the passive infrared sensor in the heat insulating material.