JP6288455B2 - Human body detector - Google Patents

Description

  The present invention relates to a human body detector, and more particularly to an infrared human body detector including an infrared detection element that detects infrared rays emitted from a human body.

  Conventionally, as this type of human body detector, for example, an automatic switch with a heat ray sensor attached to a ceiling is known (Patent Document 1).

  The automatic switch with a heat ray sensor includes a heat ray sensor that detects a heat ray emitted from a human body, and a switch that is inserted into a power supply path from a power source to a load and turned on and off according to the output of the heat ray sensor. The automatic switch with a heat ray sensor includes a lens block having a condensing lens that condenses heat rays from the detection range on a light receiving portion of the heat ray sensor. The automatic switch with a heat ray sensor includes a housing in which the switch and the heat ray sensor are housed. The housing has a window hole that exposes the condenser lens. The housing holds the lens block rotatably.

  The lens block has a holding frame held by the housing. The holding frame is formed in a cylindrical shape, and one end is closed with a condensing lens.

JP 2005-135613 A

  In the automatic switch with a heat ray sensor, malfunction may occur when the door of the room where the automatic switch with the heat ray sensor is arranged is opened or closed.

  The objective of this invention is providing the human body detector which can suppress generation | occurrence | production of a malfunctioning.

  The human body detector of the present invention includes an infrared sensor module that outputs a human body detection signal based on an output signal of an infrared detection element, and a housing that houses the infrared sensor module. The infrared sensor module includes an infrared sensor having the infrared detection element and a circuit board on which the infrared sensor is mounted. The infrared sensor includes the infrared detection element and a package. The package includes a package main body in which the infrared detection element is accommodated, an infrared transmission member that is provided in a portion of the package main body facing the light receiving surface of the infrared detection element and transmits infrared rays, and a terminal. The housing is formed with an opening for exposing the infrared sensor. The human body detector of the present invention further includes a protective cover that is disposed so as to cover the infrared sensor and closes the opening. The protective cover includes a dome-shaped lens member having a lens that collects infrared rays on the infrared detection element, and a holding member that is disposed between the housing and the lens member in the opening and holds the lens member. . The holding member includes a frame-like holding frame that holds the lens member and is held by the housing, a wall portion that surrounds the infrared sensor inside an opening edge of the lens member, the holding frame, and the wall portion And a connecting portion that connects the two.

  In the human body detector of the present invention, it is possible to suppress the occurrence of malfunction.

FIG. 1A is a schematic longitudinal sectional view of the human body detector of the embodiment. FIG. 1B is an enlarged view of a main part of FIG. 1A. FIG. 2 is a schematic exploded perspective view of the human body detector according to the embodiment. FIG. 3A is a schematic plan view of an infrared detection element in the human body detector according to the embodiment. 3B is a schematic cross-sectional view taken along the line X1-X1 of FIG. 3A. FIG. 4 is a schematic explanatory diagram of a light receiving surface of an infrared detecting element in the human body detector according to the embodiment. FIG. 5 is a circuit block diagram of the infrared sensor module in the human body detector according to the embodiment. FIG. 6 is a schematic perspective view of a protective cover in the human body detector according to the embodiment. FIG. 7 is a schematic exploded perspective view of the protective cover in the human body detector according to the embodiment. FIG. 8 is a schematic perspective view of a partially broken protective cover in the human body detector of the embodiment. FIG. 9A is a schematic perspective view of a holding member in the human body detector according to the embodiment. FIG. 9B is a schematic plan view of a holding member in the human body detector according to the embodiment. FIG. 9C is a schematic bottom view of the holding member in the human body detector according to the embodiment. FIG. 10 is a schematic perspective view of a leaf spring in the human body detector according to the embodiment. FIG. 11A is a schematic perspective view of a holding member in the human body detector of the first modification. FIG. 11B is a schematic plan view of the holding member in the human body detector of the first modification. FIG. 11C is a schematic bottom view of the holding member in the human body detector of the first modified example. FIG. 12 is a schematic cross-sectional view of a main part of a human body detector according to a second modification. FIG. 13: is a principal part schematic sectional drawing in the human body detector of a 3rd modification. FIG. 14 is a schematic bottom view of the main part of the human body detector of the fourth modified example. FIG. 15: is a principal part schematic sectional drawing in the human body detector of a 5th modification. FIG. 16 is a schematic cross-sectional view of a main part of a human body detector according to a sixth modification. FIG. 17 is a schematic cross-sectional view of a main part of a human body detector according to a seventh modification.

  Each figure described in the following embodiment is a schematic diagram, and the ratio of each size and thickness of each component does not necessarily reflect an actual dimensional ratio. In addition, the materials, numerical values, and the like described in the embodiments are merely preferable examples and are not intended to be limited thereto. Furthermore, the present invention can be appropriately modified in configuration without departing from the scope of its technical idea.

  Below, the human body detector 1 of this embodiment is demonstrated based on FIG. 1A, 1B, 2, 3A, 3B, 4-8, 9A, 9B, 9C, and 10. FIG.

  The human body detector 1 includes an infrared sensor module 2 that outputs a human body detection signal based on an output signal of the infrared detection element 31, and a housing 5 that houses the infrared sensor module 2. The infrared sensor module 2 includes an infrared sensor 3 having an infrared detection element 31 and a circuit board 4 on which the infrared sensor 3 is mounted. The infrared sensor 3 includes an infrared detection element 31 and a package 32. The package 32 includes a package main body 33 in which the infrared detection element 31 is accommodated, and an infrared transmission member that transmits infrared rays provided in a portion of the package main body 33 that faces the light receiving surface 31a (see FIGS. 1B and 4) of the infrared detection element 31. 34 and a terminal 35. The housing 5 is formed with an opening 51 through which the infrared sensor 3 is exposed. The human body detector 1 further includes a protective cover 6 that is disposed so as to cover the infrared sensor 3 and closes the opening 51. The protective cover 6 is disposed between the housing 5 and the lens member 7 in the opening 51 and holds the lens member 7 in the opening 51, and the dome-shaped lens member 7 having a lens 71 that collects infrared rays on the infrared detection element 31. Holding member 8. The holding member 8 includes a frame-like holding frame 81 that holds the lens member 7 and is held by the housing 5, a wall portion 82 that surrounds the infrared sensor 3 inside the opening edge of the lens member 7, and the holding frame 81 and the wall A connecting portion 83 that connects the portion 82. In the human body detector 1 having the above configuration, it is possible to suppress the occurrence of malfunction.

  Each component of the human body detector 1 will be described in more detail below.

  The human body detector 1 can be used by being attached to the ceiling, for example, as in the conventional automatic switch with a heat ray sensor.

  For example, as shown in FIGS. 3A, 3B and 4, the infrared detection element 31 can be configured by a quad-type pyroelectric element in which four detection units 314 are formed on one pyroelectric substrate 310. .

  In the infrared detection element 31, four detection units 314 are arranged in a 2 × 2 array on one pyroelectric substrate 310. In the infrared detection element 31, the planar view shape of each detection unit 314 can be a square shape. In the infrared detection element 31, the four detection units 314 are arranged so that the centers of the detection units 314 are positioned at the four corners of the virtual square VR <b> 1 (see FIG. 4) at the center of the pyroelectric substrate 310. The virtual square VR1 is inside the outer peripheral line 310d of the pyroelectric substrate 310.

The pyroelectric substrate 310 is a substrate having pyroelectric properties. The pyroelectric substrate 310 is made of, for example, a single crystal LiTaO ₃ substrate.

  The detection unit 314 includes a front electrode 315 formed on the front surface 311 of the pyroelectric substrate 310, a back electrode 316 formed on the rear surface 312 of the pyroelectric substrate 310, and the front electrode 315 and the back surface of the pyroelectric substrate 310. A capacitor including a portion 313 sandwiched between electrodes 316. In FIG. 3A, the polarity of the surface electrode 315 located on the infrared transmitting member 34 side in each detection unit 314 is indicated by the signs “+” and “−”. The light receiving surface 324 of the detection unit 314 is the surface of the surface electrode 315. In the infrared detection element 31, among the four detection units 314, two detection units 314 having the same polarity on one diagonal line of the virtual square VR1 are connected in parallel, and the same polarity 2 on the other diagonal line. The detection units 314 are connected in parallel. In short, the infrared detection element 31 is formed by connecting two detection units 314 arranged side by side in the left-right direction in FIG. 3A in antiparallel and side by side in the vertical direction in FIG. 3A. The two detection units 314 are connected in antiparallel.

  When the infrared detection element 31 includes a plurality of detection units 314, the light receiving surface 31a of the infrared detection element 31 is an outer peripheral line of the smallest convex polygon VR2 (see FIG. 4) that includes the plurality of light receiving surfaces 324. It means the surface of the area surrounded by. Therefore, in the example of FIG. 3, the smallest convex polygon VR2 is a square larger than the above-described virtual square VR1.

  As shown in FIG. 1B, the package main body 33 in the infrared sensor 3 includes a pedestal 36 and a cap 37 fixed to the pedestal 36. The package body 33 has a window hole 37 d formed at a portion of the cap 37 that faces the light receiving surface 31 a of the infrared detection element 31. In the package 32, the window hole 37 d of the package body 33 is closed by the infrared transmitting member 34.

  The pedestal 36 is preferably made of metal. The pedestal 36 is formed in a disk shape. A flange 36 b that is thinner than the central portion of the pedestal 36 is formed on the periphery of the pedestal 36.

  The cap 37 is preferably made of metal. The cap 37 preferably includes a cylindrical body 37a, a first flange 37b, and a second flange 37c. The cylindrical body 37a is formed in a cylindrical shape. The first flange 37b protrudes outward from a first end 37aa on the side close to the pedestal 36 in the cylindrical body 37a. The second flange 37c protrudes inward from a second end 37ab opposite to the first end 37aa in the cylindrical body 37a. In the cap 37, the inner peripheral surface of the second flange 37c constitutes the inner peripheral surface of the window hole 37d. The cap 37 has a bottomed cylindrical shape as a whole.

  The terminal 35 is provided so as to penetrate in the thickness direction of the pedestal 36. The terminal 35 is formed in a pin shape. The package 32 includes three terminals 35. In short, the package 32 includes three terminals 35 held by the pedestal 36. In the package 32, one of the three terminals 35 constitutes a terminal for taking out a human body detection signal, another one terminal 35 constitutes a power feeding terminal, and the remaining one terminal 35 has Configures the ground terminal.

  In the package 32, the flange 36b of the pedestal 36 and the first flange 37b of the cap 37 are joined by welding so as to ensure airtightness.

  For example, a silicon substrate or a germanium substrate can be used as the infrared transmitting member 34. The infrared transmitting member 34 preferably includes an appropriate optical filter film, antireflection film, and the like.

  As shown in FIG. 5, the infrared sensor module 2 preferably includes a signal processing circuit 305 in addition to the infrared detection element 31. The signal processing circuit 305 includes an amplifier circuit 301, a band filter 302, a comparison circuit 303, and an output circuit 304.

  In the signal processing circuit 305, the amplifier circuit 301, the band filter 302, the comparison circuit 303, and the output circuit 304 are preferably integrated in one IC element. In the infrared sensor 3, a substrate 307 (see FIG. 1B) on which the infrared detection element 31 and the component parts of the signal processing circuit 305 (for example, the above-described IC element) are mounted is housed in the package body 33. preferable. The substrate 307 can be configured by, for example, an MID (Molded Interconnect Devices) substrate. The substrate 307 is not limited to an MID substrate, and can be constituted by, for example, a component built-in substrate, a ceramic substrate, a printed substrate, or the like.

  The amplifier circuit 301 is a circuit that amplifies the output signal of the infrared detection element 31. The amplifier circuit 301 can be configured by, for example, a current-voltage conversion circuit and a voltage amplifier circuit. The current-voltage conversion circuit is a circuit that converts a current signal that is an output signal output from the infrared detection element 31 into a voltage signal and outputs the voltage signal. The voltage amplification circuit is a circuit that amplifies and outputs a voltage signal in a predetermined frequency band among the voltage signals converted by the current-voltage conversion circuit.

  The band filter 302 is a filter that removes unnecessary frequency components that become noise from the voltage signal amplified by the amplifier circuit 301.

  The comparison circuit 303 is a circuit that compares the voltage signal amplified by the amplifier circuit 301 with a preset threshold value and determines whether or not the voltage signal exceeds the threshold value. The comparison circuit 303 can be configured using, for example, a comparator.

  The output circuit 304 is a circuit that outputs a human body detection signal as an output signal when the comparison circuit 303 determines that the voltage signal has exceeded a threshold value.

  The infrared sensor module 2 is not limited to the example in which the components of the signal processing circuit 305 are housed in the package 32, and some or all of the components of the signal processing circuit 305 are mounted on the circuit board 4 separately from the infrared sensor 3. A configuration may be adopted.

  The circuit board 4 (hereinafter, also referred to as “first circuit board 4”) can be configured by a printed board, for example.

  As shown in FIGS. 1A and 2, the human body detector 1 preferably includes a circuit module 9 separately from the infrared sensor module 2. The circuit module 9 includes a switch element 91, a control circuit component, an external connection terminal, a circuit board 94 (hereinafter referred to as “second circuit”) on which the switch element 91, the control circuit component, and the external connection terminal are mounted. A substrate 94 ”). The second circuit board 94 is disposed on the second surface side opposite to the first surface on which the infrared sensor 3 is disposed in the first circuit board 4. The second circuit board 94 is disposed away from the first circuit board 4 in the thickness direction of the first circuit board 4. The second circuit board 94 is electrically connected to the first circuit board 4 by lead wires or the like.

  As the switch element 91, for example, a semiconductor switch element can be adopted. An example of the semiconductor switch element is a bidirectional thyristor. The switch element 91 is not limited to a semiconductor switch element, and for example, a relay contact or the like may be employed.

  The control circuit is configured to control the switch element 91 based on a human body detection signal output from the output circuit 304 of the infrared sensor module 2.

  The external connection terminal can be constituted by a quick connection terminal to which an electric wire inserted into the housing 5 is electrically and mechanically connected through an electric wire insertion hole formed in the upper wall of the housing 5.

  The quick connection terminal includes a metal terminal plate mounted on the second circuit board 94 and a leaf spring that holds the electric wire between the terminal plate. The plate spring in the quick connection terminal can be formed by, for example, bending a conductive plate made of a band-shaped metal plate or the like. It is preferable that the human body detector 1 is detachably attached with a terminal cover 56 that covers an electric wire insertion hole or the like. Thereby, for example, when the human body detector 1 is used by being attached to the ceiling without using an embedding box for wiring equipment, dust or water droplets enter the wire insertion hole and the like and adhere to the external connection terminal. Can be suppressed. The terminal cover 56 is preferably formed of a synthetic resin, for example.

  The circuit module 9 includes a pair of power supply terminals, a pair of load terminals, and a pair of slave terminals as external connection terminals. In short, the circuit module 9 includes six external connection terminals. The switch element 91 is connected between the first conductor part electrically connected to the power supply terminal and the second conductor part electrically connected to the load terminal in the second circuit board 94. The pair of child device terminals can be connected to a child device having substantially the same structure as the human body detector 1 with the human body detector 1 as a parent device. The slave unit includes the infrared sensor module 2 but does not include the switch element 91. When the human body detection signal is output from the infrared sensor module 2, the slave unit changes the voltage between the signal lines connecting the slave unit and the pair of slave unit terminals to the control circuit of the master unit. A detection signal can be transmitted. The second circuit board 94 can be configured by a printed board.

  The human body detector 1 can be used, for example, by connecting a series circuit of a power source and a load to be controlled between a power source terminal and a load terminal. Thereby, the human body detector 1 can control the on / off of the load by controlling the on / off of the switch element 91 based on the output signal of the infrared sensor module 2. In short, the human body detector 1 can be used as a load control device that controls a load to be controlled. Examples of the load to be controlled include a lighting load, an air conditioner, and a ventilation fan.

  For example, if the load to be controlled is an illumination load, the human body detector 1 has a person in the room by setting the detection area of the infrared sensor 3 in the room where the illumination load is installed. The lighting load can be turned on and off according to whether or not it exists. Therefore, for example, the human body detector 1 can turn on the lighting load when a person enters the room and turn off the lighting load when the person leaves the room.

  As shown in FIGS. 1A and 2, the housing 5 is configured by coupling a body 52 and a cover 53. The body 52 is made of a synthetic resin and is formed in a box shape having an open upper surface. The cover 53 is formed in a box shape having an open bottom surface. The body 52 is provided with a plurality of assembly pieces 52b protruding upward from the upper edge. Each assembly piece 52b has an assembly hole 52c. As for the cover 53, the assembly protrusion 53c which fits in the assembly hole 52c protrudes and is provided in the outer peripheral surface of the lower end part.

  The housing 5 includes a flange 54 that extends laterally from the lower end of the body 52. The flange 54 preferably has a circular outer periphery.

  In the housing 5, the opening 51 described above is formed at the center of the lower end of the body 52. The opening shape of the opening 51 is preferably circular.

  The human body detector 1 includes, for example, a ceiling using a flange 54, a tightening screw 560 inserted through the screw insertion hole 54 b of the flange 54, and a clip metal 570 fitted to the shaft portion 562 of the tightening screw 560. It can be attached to the material 100. The cover 53 is formed with a storage portion 55 for storing the shaft portion 562 of the tightening screw 560, and the storage portion 55 is formed in a rectangular parallelepiped shape with one side surface and a lower surface opened. A slit 551 is formed at the upper end of the storage portion 55 to allow the metal fittings 570 to enter and exit within a plane orthogonal to the vertical direction.

  For example, when the human body detector 1 is constructed by replacing an existing automatic switch with a heat ray sensor or the like, the circular embedded hole 101 formed in the ceiling member 100 as shown by a two-dot chain line in FIG. 1A. May be larger than the outer diameter of the flange 54. In this case, the human body detector 1 can be configured to include a plate frame 59 having an outer diameter larger than that of the flange 54. The plate frame 59 is preferably formed of, for example, a synthetic resin. The plate frame 59 is provided with an opening 591 into which the housing 5 can be inserted, and a recess 592 for accommodating the flange 54 of the housing 5 is formed in the periphery of the opening 591 on the lower surface. In FIG. 1A, the ceiling material 100 in the case where the inner diameter of the embedded hole 101 is smaller than the outer diameter of the flange 54 is indicated by a one-dot chain line.

  In the human body detector 1, when the head 561 of the tightening screw 560 is turned in a state in which the pinch metal 570 is in the slit 551, the pinch metal 570 comes out of the slit 551 and moves downward. Therefore, when the human body detector 1 rotates the tightening screw 560 in a state where the upper surface of the flange 54 or the upper surface of the plate frame 59 is in contact with the lower surface of the ceiling material 100, the pinching metal fitting 570 comes out of the slit 551 and the flange 54. Move in the direction approaching. Therefore, the human body detector 1 can sandwich the ceiling material 100 between the sandwiching fitting 570 and the flange 54 or the plate frame 59.

  The flange 54 of the human body detector 1 is inserted with a screw that fits into a screw hole of an embedding box arranged on the upper side of the ceiling material 100 or a tapping screw that is used when the human body detector 1 is directly attached to the ceiling material 100. Two insertion holes 54c are formed. The human body detector 1 preferably includes a decorative plate 58 that covers the lower surface of the housing 5. The decorative plate 58 is detachably attached to the housing 5. The outer peripheral shape of the decorative plate 58 is preferably circular. The outer diameter of the decorative plate 58 is preferably substantially the same as the outer diameter of the flange 54. The decorative plate 58 is provided with four hooks protruding from the upper surface, and can be attached to the housing 5 by inserting the hooks into the attachment holes 54d of the flange 54 and hooking the hooks on the periphery of the attachment holes 54d. The decorative plate 58 is a plate for improving the appearance of the human body detector 1. The decorative plate 58 is preferably formed of a synthetic resin. An opening 581 for exposing the protective cover 6 is formed at the center of the decorative plate 58. The opening shape of the opening 581 is preferably circular.

  As a material of the lens member 7 shown in FIGS. 1A, 1B, 2 and 6 to 8, it is preferable to employ, for example, polyethylene. The lens member 7 can be formed by, for example, a molding method. As the molding method, for example, an injection molding method, a compression molding method, or the like can be employed. For example, the lens member 7 is preferably configured to suppress the infrared sensor 3 from being visually recognized by a person who has seen the human body detector 1. For this reason, as a material of the lens member 7, it is preferable to employ, for example, polyethylene to which a white pigment is added. As the white pigment, it is preferable to employ inorganic pigments such as titanium dioxide and zinc white (zinc oxide).

  Each lens 71 of the lens member 7 is a condensing lens, and is constituted by a convex lens. The lens member 7 is preferably designed so that the focal points of each lens 71 on the infrared detection element 31 side are at the same position.

  As shown in FIGS. 7 and 8, the lens member 7 is integrally formed with a lens array 700 including a plurality of lenses 71. In the lens member 7, a lens array 700 is formed on a lens member main body 70 formed in a dome shape. In the lens array 700, a first surface 701 on which infrared rays are incident is configured by a group of light incident surfaces of the lenses 71, and a second surface 702 from which infrared rays are emitted is configured by a group of light emission surfaces of the lenses 71. ing. Here, in the lens array 700, the first surface 701 is constituted by a part of a hemispherical surface, and the second surface 702 has irregularities. Thereby, the lens array 700 can be improved in appearance as compared with the case where the first surface 701 has irregularities.

  In the lens array 700, the boundary between the light emitting surfaces of the adjacent lenses 71 is preferably linear. Thereby, the lens array 700 can reduce the gap between the adjacent lenses 71. Therefore, the human body detector 1 can achieve high sensitivity.

  In the lens member 7, it is preferable that the thickness of a portion other than the plurality of lenses 71 in the lens member main body 70 having the plurality of lenses 71 is larger than the thickness of each lens 71. Thereby, the human body detector 1 can attenuate infrared rays from unnecessary directions as compared with the case where the thickness of the portions other than the plurality of lenses 71 in the lens member 7 is equal to or less than the thickness of each lens 71. Become. In short, the human body detector 1 can reduce the transmittance of infrared rays incident on the lens member 7 from an unnecessary direction other than the detection area. Therefore, the human body detector 1 can reduce the amount of incident infrared rays that are incident on the infrared detection element 31 after entering the lens member 7 from an unnecessary direction, and can suppress the occurrence of erroneous detection. .

  Examples of infrared rays to be controlled that are controlled by the lens 71 include infrared rays having a wavelength range of 5 μm to 25 μm. In the lens 71, as the thickness of the lens 71 increases, the transmittance of infrared rays to be controlled decreases. When the lens 71 has a thickness of 0.1 mm, the transmittance of the infrared light to be controlled that is incident perpendicularly decreases by approximately 10%. The term “perpendicularly incident” means that the light is incident on an arbitrary point on the light incident surface of the lens 71 along the normal of the arbitrary point. Further, in the lens 71, there is a concern that the optical path length of the infrared light to be controlled that is obliquely incident on an arbitrary point on the light incident surface becomes longer than the thickness of the lens 71 corresponding to the arbitrary point and the transmittance becomes too low. is there. The term “obliquely incident” means that the light is incident on an arbitrary point on the light incident surface of the lens 71 from a direction inclined with respect to the normal of the arbitrary point.

  The detection area of the human body detector 1 is determined by the infrared light receiving path. The infrared light receiving path is a three-dimensional region formed when the infrared bundle incident on the detection unit 314 through the lens 71 is extended in a direction opposite to the direction in which the infrared light travels. In other words, the infrared ray receiving path means an infrared ray passing region through which an infrared ray bundle used for forming an image on the light receiving surface 324 of the detecting unit 314 of the infrared ray detecting element 31 can pass. Furthermore, the infrared light receiving path is an effective area for detecting infrared rays from the human body.

  The detection area of the human body detector 1 can be substantially determined by the infrared detection element 31 and the lens member 7. In this case, in the detection area of the human body detector 1, as many infrared light receiving paths as the number of detection units 314 are formed for each lens 71.

  As shown in FIGS. 1B, 7 and 8, the lens member 7 is integrally provided with two hooks 73 protruding from the opening edge of the lens member main body 70.

  1A, 1B, 2, 6-8, 9A, 9B and 9C are formed of a synthetic resin. As the synthetic resin that is a material of the holding member 8, for example, ABS (acrylonitrile butadiene styrene) or the like can be employed. The holding member 8 is preferably formed of a molded product made of a material obtained by adding a black pigment or a white pigment to a synthetic resin. As the black pigment and the white pigment, inorganic pigments are preferable. As the black pigment, for example, carbon black can be employed. Examples of white pigments that can be used include titanium dioxide and zinc white (zinc oxide).

  On the inner peripheral surface of the holding frame 81 in the holding member 8, a stepped portion 81c is provided that makes the inner diameter of the first end 81a in the axial direction of the holding frame 81 smaller than the inner diameter of the second end 81b. In the protective cover 6, the holding frame 81 holds the lens member 7 by the hook 73 of the lens member 7 being hooked on the stepped portion 81 c of the holding frame 81. Two attachment holes 86 (see FIGS. 9B and 9C) into which the two hooks 73 can be inserted are formed in the connecting portion 83. In short, the lens member 7 is held by the holding frame 81 by inserting the hook 73 into the mounting hole 86 and hooking it on the stepped portion 81c. The amount of insertion of the lens member 7 into the holding frame 81 is limited by the connecting portion 83. Therefore, the lens member 7 is prevented from coming off from the holding member 8.

  The outer peripheral surface of the holding frame 81 is constituted by a part of a spherical surface. The holding member 8 includes two shaft portions 85 protruding from the outer peripheral surface of the holding frame 81. The shaft portion 85 is formed in a semi-cylindrical shape. The shaft portion 85 has a semi-cylindrical surface on the side close to the first end portion 81 a in the direction along the axial direction of the holding frame 81. The holding member 8 preferably has a center of the spherical surface on a straight line connecting the two shaft portions 85.

  The wall part 82 and the connecting part 83 of the holding member 8 will be described later.

  The human body detector 1 includes a leaf spring 10 (see FIGS. 2 and 10) that holds the protective cover 6 between the housing 5. In short, the leaf spring 10 gives a force in a direction to press the shaft portion 85 against the upper surface of the lower wall of the body 52 against the protective cover 6.

  Therefore, the human body detector 1 can rotate the protective cover 6 around the axis of the pair of shaft portions 85 with respect to the housing 5. Thereby, since the human body detector 1 can change the direction of the lens member 7, it can change a detection area. The human body detector 1 is designed so that the focal point of each lens 71 on the infrared detection element 31 side and the center 31b of the light receiving surface 31a of the infrared detection element 31 shown in FIG. 4 are located at the center of the spherical surface. Is preferred. Thereby, the human body detector 1 can focus the lens 71 on the side of the infrared detection element 31 on the center 31 b of the light receiving surface 31 a of the infrared detection element 31 regardless of the direction of the protective cover 6.

  The housing 5 includes a cylindrical spring holding portion 512 that protrudes upward from the periphery of the opening 51 at the center of the lower wall of the body 52. The inner diameter of the spring holding portion 512 is set to be slightly larger than the distance between the tips of the pair of shaft portions 85 of the protective cover 6. Thereby, in the human body detector 1, the movement of the protective cover 6 in the direction along the upper surface of the lower wall of the body 52 is regulated by the spring holding portion 512.

  In the human body detector 1, the shaft portion 85 can rotate in the direction along the inner peripheral surface of the spring holding portion 512 inside the spring holding portion 512 in the peripheral portion of the opening 51. In short, the human body detector 1 includes the protective cover 6 in a plane perpendicular to the vertical direction of the housing 5 in a state where the semi-cylindrical surface of the shaft portion 85 hits the peripheral portion of the opening 51 on the upper surface of the lower wall of the body 52. Can be rotated.

  As shown in FIG. 10, the leaf spring 10 includes a first plate piece 111, a second plate piece 112, and four third plate pieces 113. The first plate piece 111 is formed in an annular shape and is fixed to the housing 5. The second plate piece 112 is separated from the first plate piece 111 inside the first plate piece 111. The second plate piece 112 sandwiches the two shaft portions 85 of the protective cover 6 with the lower wall of the body 52. In the leaf spring 10, the first plate piece 111 and the second plate piece 112 are preferably arranged concentrically. The third plate piece 113 is between the first plate piece 111 and the second plate piece 112, and connects the first plate piece 111 and the second plate piece 112. The third plate piece 113 is formed in an arc shape and is arranged away from the inner peripheral surface of the first plate piece 111 and the outer peripheral surface of the second plate piece 112. The third plate piece 113 is connected to the inner peripheral surface of the first plate piece 111 by bending the first end portion in the length direction toward the first plate piece 111. The third plate 113 is connected to the outer peripheral surface of the second plate 112 by bending the second end portion in the length direction toward the second plate 112. Each of the third plate pieces 113 has the same shape, and is preferably arranged at substantially equal intervals in the direction along the inner circumferential direction of the first plate piece 111. The first plate piece 111 is provided with four protruding pieces 114 bent in the thickness direction.

  On the upper surface of the spring holding portion 512, two arc-shaped protruding portions having a height from the lower wall of the body 52 larger than other portions of the spring holding portion 512 are provided, and slits are provided at both ends of the protruding portion. Is formed. The leaf spring 10 can elastically contact the inner surface of the slit by inserting the protruding piece 114 of the first plate piece 111 into the slit.

  The inner diameter of the second plate piece 112 is set to be approximately the same as the outer diameter at a predetermined position on the second end 81 b side of the shaft 85 in the axial direction of the holding frame 81. Accordingly, in the human body detector 1, the inner peripheral surface of the second plate piece 112 and the outer peripheral surface of the holding frame 81 are in contact with each other. Therefore, the human body detector 1 protects against the frictional force generated between the inner peripheral surface of the second plate piece 112 of the leaf spring 10 and the outer peripheral surface of the holding frame 81 when the orientation of the protective cover 6 is changed. The cover 6 is rotated. Therefore, the human body detector 1 can suppress the rotation of the protective cover 6 after rotating the protective cover 6.

  The leaf spring 10 can be formed, for example, by punching or bending a metal plate.

  By the way, the inventors of the present application have studied a mechanism in which a malfunction occurs when opening or closing a door of a room where the automatic switch with a heat ray sensor is arranged in the conventional automatic switch with a heat ray sensor. Then, the inventors of the present application, in a state where the temperature of the package of the heat ray sensor is rising due to heat generation of the heat-generating component, the gas flows into the space around the heat ray sensor through the gap between the condenser lens and the holding frame. Since the temperature of the liquid crystal was cooled and a temperature change occurred, it was thought that malfunction occurred.

  Therefore, the human body detector 1 according to the present embodiment has a configuration in which the above-described wall portion 82 is provided on the holding member 8 and a connecting portion 83 that connects the holding frame 81 and the wall portion 82 is provided. Thereby, in the human body detector 1 of this embodiment, it becomes possible to suppress a malfunction from occurring when the door of the room is opened or closed. More specifically, in the human body detector 1 of the present embodiment, the temperature of the package main body 33 due to the air flow is less likely to occur due to the fact that the gas flowing from the outside does not easily reach the package main body 33 of the infrared sensor 3, and malfunctions occur. It is assumed that it is possible to suppress the occurrence of

  The wall 82 is preferably formed in a cylindrical shape. In the wall portion 82, an end 82 a far from the circuit board 4 (hereinafter also referred to as “lower end 82 a”) is farther from the circuit board 4 than the infrared transmitting member 34 in the direction along the thickness direction of the circuit board 4. Preferably it is in position. In short, it is preferable that the human body detector 1 has the lower end 82a of the wall portion 82 below the infrared transmitting member 34 in the vertical direction. As a result, the human body detector 1 makes it difficult for the airflow to circulate to the lower surface side of the infrared transmission member 34, and suppresses a temperature change due to the airflow of the infrared transmission member 34 close to the light receiving surface 31 a of the infrared detection element 31. The occurrence of malfunctions can be further suppressed. The wall portion 82 is more preferably a cylindrical shape as a cylindrical shape.

  The wall 82 has an end 82b on the side close to the circuit board 4 (hereinafter also referred to as “upper end 82b”) at a position away from the circuit board 4 in the direction along the thickness direction of the circuit board 4, and It is preferable to be at a position closer to the circuit board 4 than the infrared transmitting member 34. In short, in the human body detector 1, the upper end 82 b of the wall portion 82 is preferably below the circuit board 4 and above the infrared transmitting member 34 in the vertical direction. As a result, the human body detector 1 makes it difficult for the airflow to circulate toward the package body 33, suppresses a temperature change due to the airflow, and further suppresses the occurrence of malfunction.

  In the human body detector 1, the infrared detection element 31 is preferably a pyroelectric element. As a result, the human body detector 1 can suppress the occurrence of malfunction due to airflow while achieving high sensitivity by using a pyroelectric element that is sensitive to temperature changes as the infrared detection element 31.

  In addition, the outer peripheral surface of the wall part 82 may be comprised by the uneven surface.

  11A, 11B, and 11C show the holding member 8 in the human body detector of the first modification. The human body detector of the first modified example has the same basic configuration as the human body detector 1 of the embodiment, and only the point that the through hole 84 is formed in the connecting portion 83 of the holding member 8 is the human body detector of the embodiment. 1 and different.

  In the human body detector of the first modified example, a through hole 84 that penetrates in the direction along the axial direction of the holding frame 81 is formed in the connecting portion 83 of the holding member 8. Thereby, even if an airflow flows in from the gap between the lens member 7 and the holding member 8, the human body detector 1 easily flows into the circuit board 4 through the through hole 84. Therefore, in the human body detector 1, it becomes difficult for the airflow to go around to the package body 33 side of the infrared sensor 3, and it is possible to suppress the occurrence of malfunction caused by the airflow.

  The holding member 8 preferably includes a plurality of through holes 84 formed in the connecting portion 83, and the plurality of through holes 84 are arranged at equal intervals in the direction along the inner circumferential direction of the holding frame 81. . Thereby, even if airflow flows in from the clearance between the lens member 7 and the holding member 8, the human body detector 1 easily flows into the circuit board 4 through the through hole 84 regardless of the inflow path. Become. Therefore, in the human body detector 1, it becomes difficult for the airflow to go around to the package body 33 side of the infrared sensor 3, and it is possible to suppress the occurrence of malfunction caused by the airflow.

  The human body detector of the second modified example has the same basic configuration as the human body detector 1 of the embodiment, and includes a sensor cover 38 surrounding the side surface of the package body 33 as shown in FIG. The difference is that the main body 33 is formed of a material having a lower thermal conductivity. Thereby, the human body detector of the second modified example can suppress the temperature change of the package main body 33, and can further suppress the occurrence of malfunction due to the airflow. The sensor cover 38 preferably has a cylindrical shape, and more preferably has a cylindrical shape.

  As a material of the sensor cover 38, for example, resin, rubber, or the like can be used. As the resin, for example, ABS, polyethylene or the like can be employed.

  The human body detector of the third modified example has the same basic configuration as the human body detector of the second modified example. As shown in FIGS. 13 and 14, the human body detector of the third modified example has a sensor cover 38 with a cylindrical sensor cover main body 381 and ribs that protrude from the inner peripheral surface of the sensor cover main body 381 and hit the side surface of the package main body 33. 384. In the human body detector of the third modified example, there is a gap 380 between the sensor cover main body 381 and the side surface of the package main body 33. Thereby, in the human body detector of the third modified example, the air layer of the gap 380 can function as a heat insulating layer, the temperature change of the package body 33 can be suppressed, and the malfunction due to the airflow occurs. Can be further suppressed. In the human body detector of the third modified example, the gap length of the gap 380 can be defined by the rib 384. The number of ribs 384 is preferably plural.

  The human body detector of the fourth modified example has the same basic configuration as the human body detector of the second modified example. As shown in FIG. 15, the human body detector of the fourth modification includes a sensor cover 38 that includes a cylindrical sensor cover main body 381 and an infrared transmission cover portion 382 that covers the infrared transmission member 34. The part 382 is made of polyethylene. Thereby, the human body detector of the fourth modified example can further suppress the temperature change of the package body 33 due to the airflow, and can further suppress the occurrence of malfunction due to the airflow.

  In the sensor cover 38 in the human body detector of the fourth modified example, it is preferable that the infrared transmission cover portion 382 transmits infrared rays and the sensor cover main body 381 blocks infrared rays and visible light. Such a sensor cover 38 can be constituted by, for example, a two-color molded product in which at least one of the additive and the concentration of the additive with respect to polyethylene is different between the infrared transmitting cover portion 382 and the sensor cover main body 381. A two-color molded product means a product that is integrally molded by supplying molding materials of different colors or types, and then injecting them simultaneously or sequentially into one mold cavity after melt plasticization. . Here, the different types of molding materials mean molding materials having the same type of additive to polyethylene and different concentrations of additives. A two-color molded product can be integrally molded using a two-color injection molding machine which is an injection molding machine of a type in which two mold injection devices are provided in one mold clamping device.

  The additive is preferably at least one selected from the group of, for example, a pigment, a hindered amine light stabilizer (HALS), and an infrared absorber. Thereby, the human body detector of the fourth modified example can prevent the wavelength conversion of incident visible light or infrared light from being performed in the sensor cover main body 381, and the visible light transmitted through the sensor cover main body 381. And it becomes possible to reduce the amount of each of infrared rays.

  The pigment may be either an organic pigment or an inorganic pigment, but an inorganic material is more preferable from the viewpoint of light resistance, weather resistance and the like. As the pigment, for example, a white pigment, a black pigment or the like can be used in both cases of an organic pigment and an inorganic pigment. As the white pigment among the inorganic pigments, for example, titanium dioxide, zinc white or the like can be used. Moreover, as a black pigment among inorganic pigments, for example, carbon black can be used.

  When the sensor cover 38 is an infrared transmitting cover portion 382 and a sensor cover main body 381 and the additive to polyethylene is a white pigment, the sensor cover main body 381 can be set to a higher concentration of the additive to polyethylene. Good. Similarly, in the sensor cover 38, when the infrared transparent cover portion 382 and the sensor cover main body 381 are both black pigments, the sensor cover main body 381 has a higher concentration of the additive relative to polyethylene. You only have to set it. Further, in the sensor cover 38, when the additive for polyethylene is different between the infrared transmitting cover portion 382 and the sensor cover main body 381, for example, the additive in the infrared transmitting cover portion 382 is a white pigment, and the sensor cover main body 381 is used. The additive can be a black pigment.

  As the infrared absorbing agent, an additive capable of improving functions such as light resistance improvement, oxidation prevention, coloring, and moldability improvement of polyethylene is preferable. Examples of such absorbents include benzotriazole ultraviolet absorbers, phosphate ester additives, phosphite esters, and the like. The hindered amine light stabilizer, like the above-described absorber, can improve functions such as improvement of light resistance, oxidation prevention, coloring, and improvement of moldability of polyethylene.

  Further, in the human body detector of the fourth modified example, since the infrared transmission cover portion 382 and the sensor cover main body 381 are configured by the above-described two-color molded product, the number of parts can be reduced and the cost can be reduced. . Further, when the sensor cover main body 381 is formed of a material other than polyethylene, it is difficult to adhere to the infrared transmitting cover portion 382 formed of polyethylene, and it is necessary to separately provide a structure for connecting the two. On the other hand, in the human body detector of the fourth modified example, it is not necessary to separately provide a structure for coupling the infrared transmitting cover portion 382 and the sensor cover main body 381, so that the shape design of the sensor cover 38 is easy. And the degree of freedom of the shape of the sensor cover 38 is increased.

  The shape of the infrared transmission cover portion 382 is a curved shape, but is not limited thereto, and may be a flat plate shape or a dome shape, for example.

  The human body detector of the fifth modified example has the same basic configuration as that of the human body detector 1 of the embodiment, and is implemented by the fact that there is a gap 390 between the package body 33 and the circuit board 4 as shown in FIG. This is different from the human body detector 1 in the form. Thereby, in the human body detector of the fifth modified example, the air layer formed by the gap 390 can function as a heat insulating layer. Therefore, in the human body detector of the fifth modified example, heat transfer from the circuit board 4 to the package body 33 can be suppressed, and the temperature change of the package body 33 due to the airflow can be suppressed. It becomes possible to suppress the malfunction due to.

  The human body detector of the sixth modified example has the same basic configuration as the human body detector of the second modified example. As shown in FIG. 17, the human body detector of the sixth modified example has a sensor cover 38 protruding from the inner peripheral surface of the cylindrical sensor cover main body 381, the sensor cover main body 381, and the package main body 33, the circuit board 4, And a rib 383 interposed therebetween. In the human body detector of the sixth modified example, there is a gap 390 between the package body 33 and the circuit board 4. Accordingly, the human body detector of the sixth modification can define the gap length of the gap 390 by the rib 383, and can further suppress the heat transfer from the circuit board 4 to the package body 33. The number of ribs 383 is preferably plural.

DESCRIPTION OF SYMBOLS 1 Human body detector 2 Infrared sensor module 3 Infrared sensor 4 Circuit board 5 Housing 6 Protective cover 7 Lens member 8 Holding member 31 Infrared detecting element 31a Light receiving surface 32 Package 33 Package main body 34 Infrared transmitting member 35 Terminal 38 Sensor cover 71 Lens 51 Opening Part 81 holding frame 82 wall part 82a end 82b end 83 connecting part 84 through hole 380 gap 381 sensor cover main body 382 infrared ray transmitting cover part 383 rib 384 rib 390 gap

Claims (11)

An infrared sensor module that outputs a human body detection signal based on an output signal of the infrared detection element; and a housing that houses the infrared sensor module;
The infrared sensor module includes an infrared sensor having the infrared detection element, and a circuit board on which the infrared sensor is mounted,
The infrared sensor includes the infrared detection element and a package,
The package includes a package main body in which the infrared detection element is housed, an infrared transmission member that is provided in a portion of the package main body facing the light receiving surface of the infrared detection element and transmits infrared rays, and a terminal.
The housing has an opening for exposing the infrared sensor,
A protective cover arranged to cover the infrared sensor and closing the opening;
The protective cover includes a dome-shaped lens member having a lens that collects infrared rays on the infrared detection element, and a holding member that is disposed between the housing and the lens member in the opening and holds the lens member. With
The holding member includes a frame-like holding frame that holds the lens member and is held by the housing, a wall portion that surrounds the infrared sensor inside an opening edge of the lens member, the holding frame, and the wall portion A connecting portion for connecting
A human body detector characterized by that. The wall portion is formed in a cylindrical shape, and an end far from the circuit board is located farther from the circuit board than the infrared transmitting member in a direction along the thickness direction of the circuit board. ,
The human body detector according to claim 1. The wall portion has an end closer to the circuit board at a position away from the circuit board in a direction along the thickness direction of the circuit board, and closer to the circuit board than the infrared transmitting member. In position,
The human body detector according to claim 2. The connecting portion is formed with a through hole penetrating in a direction along the axial direction of the holding frame.
The human body detector according to any one of claims 1 to 3. The number of the through holes formed in the connecting portion is a plurality, and the plurality of through holes are arranged at equal intervals in the direction along the inner circumferential direction of the holding frame.
The human body detector according to claim 4. The infrared detection element is a pyroelectric element;
The human body detector according to claim 1, wherein the human body detector is a human body detector. A sensor cover surrounding the side surface of the package body;
The sensor cover is formed of a material having a lower thermal conductivity than the package body.
The human body detector according to any one of claims 1 to 6. The sensor cover includes a cylindrical sensor cover main body, and a rib that protrudes from an inner peripheral surface of the sensor cover main body and hits a side surface of the package main body,
There is a gap between the sensor cover main body and the side surface of the package main body,
The human body detector according to claim 7. The sensor cover includes a cylindrical sensor cover main body and an infrared transmission cover portion that covers the infrared transmission member,
The infrared transmission cover part is made of polyethylene,
The human body detector according to claim 7 or 8, wherein There is a gap between the package body and the circuit board,
The human body detector according to claim 1, wherein the human body detector is a human body detector. The sensor cover includes a cylindrical sensor cover main body, and a rib projecting from an inner peripheral surface of the sensor cover main body and interposed between the package main body and the circuit board,
There is a gap between the package body and the circuit board,
The human body detector according to claim 7, wherein the human body detector is a human body detector.

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