JPH0193893A - Sensor unit structure for photoelectric smoke sensor - Google Patents

Abstract

PURPOSE:To diversify a specification and to attain a compact structure by separately forming a base, a cover and a sensor unit. CONSTITUTION:A photoelectric smoke sensor consists of the base 16 fixed to a mounting face, the cover 17 mounted on the lower face of the base and the sensor unit inserted from the opening 17a of the cover 17 and mechanically and electrically connected to the base 16. The cover 17 is covered on the lower face of the base 16 by engaging an engaging claw disposed on an upper end limb with an engaging recessed part 16d disposed at the lower end limb of the base 16. The sensor unit 18 is inserted from the central opening 17a of the cover 17 to fit an engaging piece 20 into the notch 16c of the base 16 downward and rotate the sensor unit 18 horizontally, thereby, engaging and connecting the engaging piece 20 to an engaging groove 16b.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a sensor unit structure of a photoelectric smoke detector.

[Background Art] Figure fjS8 shows a conventional photoelectric smoke detector. In this conventional example, a printed circuit board 2 is arranged below a base 1 on which a shield plate 4 is provided, and the external ceiling surface of the printed circuit board 2 is A lead wire 7 from a printed circuit board 2 with a feedthrough capacitor 6 passed through it is connected to an input/output terminal 5 provided at the input/output terminal 5 provided on the board. The light-emitting element 10 and the light-receiving element 11 attached to the metal substrate 9 fixed to the lower surface of the printed circuit board 2 with free-standing legs 8 are mounted downward through an opening window 12 opened in the center of the shield cover 3. It's exposing. Then, the upper edge of the cover 14 is locked and fixed to the edge of the base 1, and the light emitting element 10 and the light receiving element 11 are attached to the cover 1.
It is stored in the dark room 13 in the lower part of 4, and the above-mentioned shield cover is
3 is covered entirely. An insect screen 15 is provided on the outer periphery of the lower part of the shield cover 3 so as to cover the smoke inlet communicating with the dark room 13.

By the way, in such a conventional example, since the cover 14 constitutes a cover for the entire sensor, the cover 14 provided with the dark room 13 is
The cover 14 is exclusively for the rechargeable type, which means that the cover 14 cannot be used for other purposes. Furthermore, there is a problem that the entire structure becomes larger.

[Objective of the Invention 1 The present invention has been made in view of the above-mentioned problems, and its purpose is to provide a sensor unit BJ structure for a photoelectric smoke detector that can be assembled compactly and does not need to be integrated with a cover. It is on offer.

[Disclosure of the Invention 1] The present invention includes a labyrinth body provided to introduce invading smoke into an internal darkroom through a labyrinth from a smoke inlet opening opened on the periphery, and a labyrinth body disposed on the opening side, A bottomed cylindrical plate with input/output terminals protruding from the outer bottom, a printed circuit board wired with a sensor circuit that drives the light emitting element and processes the light reception signal of the light receiving element, and is housed inside the plate. A bottomed cylindrical shield box containing the printed circuit board, the light emitting element which is disposed between the labyrinth body and the printed circuit board, and which projects light into the darkroom of the labyrinth body. The present invention will be described below with reference to examples.

Dog W Figure 1 shows an overall perspective view of a rechargeable smoke detector using an embodiment. It consists of a cover 17 attached to the lower surface of the base 16, and a sensor unit 18 that is inserted through an opening 17a in the center of the cover 17 and is mechanically coupled to the base 16 and electrically connected.

The cover 17 has a locking claw (not shown) provided on the upper edge.
The locking hole el 6d provided on the lower edge of the base 16
It is attached to the lower surface of the base 16 by being locked to the base 16.

On the other hand, the base 16 has a locking groove 16 [1 formed all around the inner peripheral surface of the central opening window 16a, and the opening window 16
Notches 16c communicating with the opening window lea and the locking groove 16b are provided at symmetrical positions with respect to the center of the cover 17, and the notches 16c are provided at the upper edge of the sensor unit 18 inserted through the central opening 17a of the cover 17. By fitting the locking piece 20 into the notch 16c from below and rotating the sensor unit 18 in the horizontal direction, the locking piece 20 is locked in the locking groove 16b, and the sensor unit 18 is mechanically coupled. It is supposed to be done. At the same time, the bottle-shaped input/output terminal 21 on the top surface of the sensor unit 18 inserted through the opening window 16a is brought into contact with a connection terminal (not shown) provided inside the base 16, and the circuit or receiver FF provided in the base 16 is connected.
1fi (not shown).

Figure @2 shows an exploded perspective view of the sensor unit 18, and the bottomed cylindrical plate 19 made of a synthetic wood Il'ff molded product serving as the upper structure integrally forms the above-mentioned locking piece 20 and also serves as an input/output A cylindrical metallic shield box 24 with a bottom is housed in which a terminal 21 is inserted and a disc-shaped printed circuit board 26 to which a sensor circuit necessary as a sensor unit 18 is wired is housed. As shown in FIG. 3, the shield box 24 has a feedthrough capacitor 35 extending from the printed circuit board 26 from the input/output end through the glued wire @ 34 and soldering to the bottom surface thereof, and a feedthrough capacitor 35 which is soldered to the input/output end which is led out from the printed circuit board 26. The shield cover 25 is mechanically and electrically engaged with a bulge 36a formed on the outer surface of the tip of the elastic leg piece 36 that protrudes from the peripheral edge of the shield cover 25.
Holes 37 for connecting the elastic legs 36 are provided in the peripheral wall in correspondence with the respective elastic leg pieces 36.

The printed circuit board 26 has electronic components on both sides that operate the sensor circuit shown in FIG. 4, and the shield box 24
The shield box 24 is placed on a piece protruding inward from the peripheral wall of the shield box 24 on the bottom of the shield box 24, or separated and insulated with an insulating sheet (not shown) disposed on the bottom of the shield box 24.
As shown in FIG. 3, the lead #I34, which is disposed in the plate 19 and soldered through the feedthrough capacitor 35 as described above, is inserted into the hollow input/output terminal 21 provided on the plate 19. Go ahead! Secure the connection at the @ part by soldering or spin processing.

Here, a reed switch 38 for testing a sensor circuit, which will be described later.
The printed circuit board 26 is disposed at a position away from the amplifier circuit 37 so that the magnetism of the drive magnet does not affect the amplifier circuit 37, which will be described later, and on the periphery so that it can be easily driven by the drive magnet. A light emitting element 39 for confirmation is provided upright on the periphery.

The shield cover 25 is recessed in a U-shaped cross section along the diameter direction to form a fitting groove 40 on the surface side, and this fitting groove 40 houses a light emitting element 28 and a light receiving element 29 for smoke detection. This is for mounting the element holder 27, and the bottom has holes 40a for each element 28 and two lead wires to be led out to the back side and soldered to the printed circuit board 26.
40b is drilled.

The element holder 27 has a base 27a made of a synthetic resin molded product.
and a case body 27b, and a light emitting element 28 is placed on both sides of the lower surface of the base 27a in a dark room 31 in a labyrinth body 30, which will be described later.
The sloped surface on which the light emitting element 28 is placed and the sloped recess 41 with the lead wire conduction notch 41a provided at the bottom so that light can be projected at just the right angle into the dark room, and the light receiving surface of the light receiving element 29 are arranged at just the right angle. A holding hole 42 is provided with an inclined inner surface along which the light receiving element 29 is placed so as to face the hole 31, and a hole (not shown) for leading out the lead wire is bored at the bottom of the holding hole 42, as shown in FIG.
, ), and a case body 27b is formed on the lower center surface.
A locking groove 43 is formed for coupling with the main body. Further, as shown in FIG. 5(b), locking claws 44 for fixing to the case body 27b are provided at both ends of both side surfaces. The case body 27b is formed into a box shape, and the base 27a is fitted into the opening, and the locking claws 44 of the base 27a are attached to the inner side of both side walls as shown in Figure 6 (,). A locking hole 45 is provided in each case, and a locking protrusion 46 that locks into the locking groove 43 is provided at the center inner bottom portion, and light is emitted from the light emitting element 28 disposed on the base 27a. A floodlight window 47 through which
A light-receiving window 48 facing the light-receiving surface of the light-receiving element 27 is formed diagonally in alignment with the respective optical axes. Furthermore, a collar piece 49 is provided protruding from the outer bottom periphery. The element holder 27 is fitted into the fitting groove 40 of the shield cover 25 on the upper surface (lower surface in FIG. 6(b)) of the flange pieces 49 on both sides, and the element holder 27 is fitted onto the lower surface of the shield cover 25 on both sides of the fitting groove 40. A small protrusion 5 inserted into a small hole 50 formed in the shield cover 25 when abutting
1 is integrally provided, and by crushing the tip of this small protrusion 51 with heat, the element holder 27 is attached to the shield cover 2.
Fixed at 5.

The lower structure consists of a labyrinth body 30, etc., and the labyrinth body 30 is made of a synthetic resin molded product, and dogleg-shaped projections 52 are integrally formed at equal intervals on the circular bottom 30a, as shown in FIG. 7(a). to form a labyrinth 32 and a dark room 31 in the center.
and a smoke inlet 33 facing the outside are communicated via a labyrinth 32.

Further, a flange 53 is integrally or separately formed on the outer periphery of the upper part to form a hat body as a whole. The outer periphery is covered with an insect repellent net 23 formed in a cylindrical shape, and this insect repellent net 23 is attached to the flange 5.
3 and a cap 22 attached to the lower part.

The lower structure consisting of the labyrinth body 30 and the like that is diseased in this way is shown in FIG.
) As shown in (b), a small protrusion 54 is formed in the shield cover 25 and inserted into a small hole 55 from below and fixed to the lower surface of the shield cover 25 by heat bonding.

The element holder 27 constructed as described above is fitted into the fitting groove 40 of the shield cover 25 and fixed by heat bonding, and then the lower structure consisting of the labyrinth body 30 is attached to the lower surface of the shield cover 25. The light emitting window 47 and the light receiving window 48 of the element holder 27 are fixed to face the dark room 31 of the labyrinth body 30. Then, the lead wires of the elements 28 and 29 of the element holder 27 are led out to the back side of the shield cover 25 through the holes 40a and 40b at the bottom of the fitting groove 40, and connected to the printed circuit board 26. Upper light emitting element 39
A notch 25a formed at the periphery of the shield cover 25
The shield cover 25 is attached to the opening of the shield box 24 with the shield cover 25 exposed to the surface side of the shield cover 25 and exposed below the square hole 56 of the flange 53 of the labyrinth body 30, and the printed circuit board 2 is attached. The lead wire 34 from the printed circuit board 2 is housed in the plate 19 and connected to the plate 1.
By connecting to two input/output terminals 21, the sensor unit 18 is completed. Note that the assembly order is not particularly limited to the above. Also labyrinth body 30
is thermally bonded to the shield cover 25, but the upper surface of the flange piece 53 may be adhesively fixed to the lower surface of the shield cover 25 or the lower end surface of the periphery of the plate during final assembly.

Next, according to the circuit diagram shown in FIG.
Explain the operation.

The line voltage connected through the input/output terminal 21 is applied to the power supply circuit 58 via the guide circuit 57, and is stabilized to a voltage necessary for the sensor circuit. This stabilized direct current is applied to the detector circuit 59, the drive circuit 60 of the monitoring status display light emitting element 39, and the amplification circuit 37 of the light reception signal.
, and are supplied to the signal processing circuit 61, respectively. Further, a light emitting element 39 is connected between the output terminals of the diode bridge 57 via a switching circuit 62, a resistor R2, and a diode D1.

In the monitoring state, the light emitting element 28 is intermittently driven by the oscillation output of the oscillation circuit 59 to emit light intermittently, and the light emitting element 39 is caused to emit light intermittently via the drive circuit 60.

The intermittent light emission of this light emitting element 39 indicates that it is in a monitoring state.

On the other hand, the light from the light emitting element 28 is projected into the dark room 31, but when there is no smoke entering the dark room 31, the amount of light received by the light receiving element 29 is small, so the signal processing circuit 61 outputs the light to the switching circuit 62. No signal is output.

Next, when smoke enters the dark room 31, the light scattered by the smoke enters the light receiving element 29, so the level of the light receiving signal increases, and when the amplified output exceeds the threshold, the signal processing circuit 61 changes the oscillation output of the oscillation circuit 59. The detection signal is synchronously taken in and the switching circuit 62 is triggered to turn on the switching circuit 62. When turned on, the input/output terminal 21 is short-circuited via the resistor R3 and the diode bridge 57, and an alarm output is generated on the line. On the other hand, the switching circuit 62 and the resistor R
Since a light emitting current flows through the light emitting element 39 through the light emitting element 2 and the diode D, the light emitting element 39 changes to a continuous lighting state to indicate that it is in the alarm operation state.

When the test reed switch SW is turned on by being driven by an external magnet, it gives a pseudo detection signal to the signal processing circuit 61 as a signal similar to the detection signal described above, triggers the switching circuit 62, and artificially activates the sensor unit 18. It is something that can be reported. If the light emitting element 39 is an element made of an alloy based on lithium or phosphorus with arsenic added, low current consumption and high brightness light emitting display can be achieved.

[Effects of the Invention] The present invention includes a labyrinth body provided to introduce invading smoke into the internal darkroom through a labyrinth from a "smoke introduction port opened at the periphery," and a labyrinth body disposed on the opening side. , a bottomed cylindrical plate with input/output terminals protruding from the outer bottom, a printed circuit board on which a sensor circuit for driving the light emitting element and processing the light reception signal of the light receiving element is wired, and the plate is housed inside the plate. and a bottomed cylindrical shield box containing the printed circuit board, the light emitting element disposed between the labyrinth body and the printed circuit board, and projecting light into the dark room of the labyrinth body, and the light emitting element that emits light inside the dark room. Since it consists of an element holder that firmly holds the above-mentioned light-receiving element that receives light, it is possible to obtain a sensor unit that does not have a cover integrated into it, making it possible to separate the base, cover, and sensor unit, allowing for diversification of specifications. In addition, the sensor unit itself can be manufactured compactly because the photoelectric part and circuit part of the light emitting element and the light receiving element can be housed in the plate together with the shield box.

[Brief explanation of the drawing]

FIG. 1 shows an embodiment of the present invention. Figure 2 is an exploded perspective view of the rechargeable smoke detector, Figure 2 is an exploded perspective view of the sensor unit as above, Figure tjS3 is an explanatory diagram of the connection of the input/output terminals as above, Figure 4 is the circuit diagram of the same as above, Figure PIS5 ( a) (+3) is a cross-sectional view and side view of the base of the above element holder, Fig. 6 (a)
(b) is a cross-sectional view and side view of the case body of the element holder as above, FIG. . 16... Base, 17... Cover, 18... Sensor unit, one... Plate, 21... Input/output terminal, 23... Insect screen, 24... Shield box, 25... ...Shield cover, 25a...q9 missing,
26... Printed circuit board, 27... Element holder, 2
7a... Base, 27b... Case body, 28... Light emitting element, 29... Light receiving element, 30... Labyrinth body, 31... Dark room, 32... Labyrinth, 33...・
Smoke inlet, 39... Light emitting element, 41... Inclined recess,
42...Holding hole, 47...Light emitting window, 48...Light receiving window, 56...Square hole Agent Patent attorney Ishi 1) 议 Figure 7 Figure 3 Figure 5 (G) (b) Figure 6 (b) Figure 7 Figure 8 Procedural amendment (voluntary) 1. Indication of the case 1988 Patent Application No. 250858 2. Title of the invention 3. Relationship with the Ill-correction case Patent applicant address 1048 Kadoma, Kadoma City, Osaka Prefecture Name (58
3) Matsushita Electric Works Co., Ltd. Representative Sadao Fujii 4, agent postal code 530 5, date of amendment order Voluntary (1) The scope of claims on pages 51 to 152 of the specification of the present application is corrected as follows. . [(1) A labyrinth body provided so that invading smoke is introduced into the internal darkroom through a labyrinth from a smoke introduction port opened on the periphery, and this labyrinth body is placed on the opening side and enters the outside bottom. A bottomed cylindrical plate with a protruding output terminal, a printed circuit board wired with a sensor circuit for driving a light emitting element and processing a light reception signal of a light receiving element, and the printed circuit board housed within the plate. a cylindrical shield box with a bottom that houses the labyrinth body, the light emitting element that emits light into the dark room of the labyrinth body, and the light receiving element that receives the light inside the dark room that is disposed between the labyrinth body and the printed circuit board. A sensor unit structure of a photoelectric smoke detector characterized by consisting of an element holder and an element holder. (2) F
n. A base having an inclined recess for placing and storing the light-receiving element, and a holding hole for placing and storing the light-receiving element on the inner surface inclined in the light-receiving direction; The photoelectric smoke according to claim 1, characterized in that the element holder is constituted by a case body in which a light emitting element is exposed to a light emitting window that is opened on the surface, and a light receiving element is exposed to a light receiving window. Structure of sensor sensor unit. (3) The light emitting element for operation confirmation provided on the printed circuit board is exposed to the outside through a hole formed in the periphery of the labyrinth body through a notch provided in the shield cover attached to the opening of the shield box. A structure of a sensor unit of a photoelectric smoke detector according to claim 1, characterized in that: ” (2) Change “sensor unit” in line 3 of fjS, page 1, to “
"Sensor unit", corrected. (3) Change the “sensor unit” in the 2nd Qf51S line above to “
"Sensor unit", corrected. (4) "Sensor unit" on page 4, line 6 of the above is corrected to "sensor unit." (5) On page 4, line 9 of the same page, ``to introduce'' is corrected by 31 to ``to introduce.'' (6) The full text of lines 18 and 19 on page 5 of tjS above is corrected as follows. [are provided respectively, and the upper edge of the sensor unit "z) 18" (7) "The machine" in page 7, line 19 of the same as [the base 1
6 Machine J (8) Insert the following sentence next to "Connect." on line 9 of the same page as above. [The cover 17 is attached to the base 16 after the sensor unit 18 is coupled to the base 16, with the sensor unit 18 exposed to the outside through the opening 17a. (9) The entire text of page 7, lines 19 to 20 of the above is corrected as follows. "The printed circuit board 26 to which the 138 is attached has been increased because the leads of the reed switch 38 may become an antenna for the oscillation circuit output and affect the amplifier circuit 37, which will be described later." (10) Same as above, page 7, line 19. Correct "to introduce" to "to introduce." (11) Correct the drawing Medium Temperature 2 as shown in the attached sheet. Agent Patent Attorney Ishi 1) Ai Shichi

Claims (3)

[Claims] (1) A labyrinth body is provided to introduce incoming smoke into the internal darkroom through a labyrinth from a smoke inlet opening on the periphery, and this labyrinth body is placed on the opening side, and input/output is provided at the outer bottom. A bottomed cylindrical plate with protruding terminals, a printed circuit board wired with a sensor circuit for driving the light emitting element and processing the light reception signal of the light receiving element, and the printed circuit board housed within the plate. A cylindrical shield box with a bottom is housed therein, and the light emitting element is disposed between the labyrinth body and the printed circuit board, and the light emitting element projects light into the dark room of the labyrinth body, and the light receiving element receives the light inside the dark room. A sensor unit structure of a photoelectric smoke detector characterized by comprising a fixed element holder. (2) It has an inclined recess in which the light-emitting element is placed and housed on an inclined surface inclined in the light-emitting direction, and a holding hole in which the light-receiving element is placed and housed in an inner surface inclined in the light-receiving direction. The element holder is constituted by a base and a case body into which the base is fitted from the bottom opening so that the light-emitting element faces the light-emitting window opened to the ceiling surface, and the light-receiving element faces the light-receiving window. A sensor unit structure of a photoelectric smoke detector according to claim 1, characterized by: (3) The light emitting element for operation confirmation provided on the printed circuit board is exposed to the outside through a hole formed in the periphery of the labyrinth body through a notch provided in the shield cover attached to the opening of the shield box. A sensor unit structure of a photoelectric smoke detector according to claim 1, characterized in that the sensor unit structure comprises: