JP2587305Y2 - Fire detector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a fire detector provided with a printed circuit board on which electric parts and the like are mounted and an electric circuit is formed.

[Prior Art] For example, a conventional fire detector includes a main body for accommodating a printed circuit board on which an electric circuit is formed as disclosed in Japanese Utility Model Publication No. 59-6288 and Japanese Patent Application Laid-Open No. 63-133292. A semiconductor heat sensor consisting of a semiconductor element whose lead varies with temperature, such as a thermistor whose leads are connected to this printed circuit board, and a cover that covers the body with the semiconductor element exposed, or As disclosed in JP-A-63-34520, a main body that accommodates a printed circuit board on which an electric circuit is formed, a cover that covers the main body, an optical table in which a labyrinth is formed, and an optical table attached to the optical table. An optical smoke detector including a light-emitting element and a light-receiving element whose leads are connected to a printed circuit board, a net covering an optical bench, a cover, and the like are often used.

[Problem to be Solved by the Invention] The electric circuit of the conventional fire detector as described above is composed of a single printed circuit board. With the increase in the number of components mounted on an electric circuit necessary for a fire detector or a relay device (for example, with increasing intelligence), it is becoming difficult to mount components on a single printed circuit board. In order to mount many components, it is necessary to enlarge the printed circuit board, but as a result, fire detectors and repeaters naturally become large,
It will not be able to meet the demand for miniaturization.

In addition, in some electric appliances, two printed circuit boards on which electric components and the like are mounted are arranged in two stages at predetermined intervals via a plurality of columns. However, the supporting column for supporting the printed circuit board having such a structure is used for mechanical coupling and positioning of the two printed circuit boards, and electrical connection between the two printed circuit boards is performed by, for example, wiring or a connector. ing. For this reason, not only is a space for a plurality of columns required on the printed circuit board, but also a space for electrical connection by a connector or the like must be provided. Since a circuit pattern cannot be provided or an electric component cannot be provided in these spaces, the space becomes a dead space, and miniaturization of the device is restricted.

Further, when two printed boards are arranged in two stages via a plurality of columns, a horizontal shift occurs due to the twist generated in the upper and lower printed boards, and an error occurs in the mounting position of the columns on each printed board. The assembling work is troublesome, and even after the assembly, the printed circuit board is displaced, so that the strength is inevitably reduced, and it is difficult to insert the printed circuit board into the main body.

In the present invention, the electric circuit of the fire detector is composed of a plurality of printed circuit boards, and by efficiently arranging the printed circuit boards, a large number of small-sized fire detectors can be efficiently produced without increasing the size of the present situation. The purpose is to obtain parts.

[Means for Solving the Problems] The fire detector according to the present invention has a bottomed frame-shaped main body in which electric components and the like are housed, various elements mounted on one surface, and a fire on the other surface. A first printed circuit board to which the detection unit is attached, and a second printed circuit board which is opposed to an element mounting surface of the first printed circuit board at a predetermined interval and is disposed close to the bottom surface of the main body; And a plurality of columns interposed between the first and second printed circuit boards, the plurality of columns connecting the first and second printed circuit boards. 1, formed of a conductive material that electrically connects an electric circuit pattern of a second printed circuit board, and the plurality of columns are densely arranged in at least one place, and the densely arranged columns are formed of an insulating material. Are integrally connected with a tying tool consisting of Those were.

Further, a female screw portion is provided on the second printed circuit board side,
The second printed circuit board is fixed to the main body by screwing a male screw member penetrating the bottom surface of the main body into the female screw portion.

Further, a plurality of column assemblies connected by the binding device are formed, and the plurality of column assemblies are arranged concentrically.

[Operation] In the fire detector configured as described above,
Since the plurality of pillars that couple the second printed circuit board are densely arranged at least at one location, even if the pillars are sparsely arranged in other areas, horizontal directions such as twists between the printed circuit boards may occur. Can withstand the power of Also, this can prevent horizontal displacement,
It is possible to eliminate an error in the mounting position of the support of each printed circuit board.

In addition, since all or a part of the support is made of a conductive material, the support can be used as a connection line of a circuit pattern on the upper and lower printed circuit boards.

Further, since the closely arranged struts are integrally connected by the binding device, the struts can be reinforced.

Also, the fire detection unit is attached to the surface of the first printed circuit board opposite to the element mounting surface.
The printed circuit board and the fire detection unit can be brought into close contact with each other. Therefore, the height of the fire detector can be reduced, and the whole can be made compact.

Further, since the second printed circuit board is fixed to the main body by a male screw member penetrating the bottom surface of the main body, the second printed circuit board can be easily fixed, and the first printed circuit board has a fixing portion to the main body. , It is possible to effectively utilize the board surface of the first printed board.

In addition, since the plurality of column assemblies connected by the binding device are arranged concentrically, even if a torsional force acts on the printed circuit board in the circumferential direction, the torsional force can be countered.

FIG. 1 is a longitudinal sectional view of an embodiment of the present invention, FIG. 2 is a plan view of a second printed circuit board with circuit patterns and circuit elements omitted, and FIG. 3 is a state in which a cover is removed. FIG. 2 is a bottom view of FIG. In the figure, (1) is a cylindrical sensor main body, (11) is an annular step provided at the lower part of the inner wall, (12) is a plurality of hooks provided at the lower edge of the inner wall, and (13) is a part of the inner wall. A plurality of steps protruding inward on the bottom side, (14) is a through hole provided in the step (13), (15)
Are mounting screws that are inserted into the through holes (14), are electrically and mechanically connected to a printed circuit board described later, and are connected to external wiring.

Reference numeral (2) denotes a sensor circuit printed circuit board (hereinafter, referred to as a first printed circuit board) on which a hybrid IC (21), other circuit elements (22), a shield case (23), a volume (24), and the like are mounted. (2a) is the MPU (2
5) and other printed circuit boards for transmission circuits to which the circuit elements (26) are attached (hereinafter referred to as a second printed circuit board)
It is. (28) is a confirmation light (see FIG. 3) made of, for example, a light emitting diode which is suspended from the periphery of the first printed circuit board (2) to the lower surface, and (29) and (29a) correspond to the mounting screw (15). It is a provided nut.

(3) is a plurality of columns for vertically connecting the first and second printed circuit boards (2) and (2a). This post (3)
Is made of a conductive material, has through-hole insertion portions (31) at both ends as shown in FIG. 4, and a large-diameter portion (32) at an intermediate portion.
When a plurality of columns (3) are juxtaposed, they are integrally connected by a binding device (33) made of an insulating material as shown in FIG. In FIG. 5 showing the binding device (33), (34) is a connecting hole of the support (3), (3)
5) is a connecting part. The tying member (33) also serves as a reinforcing material for the column (3). The through-hole insertion portions (31) of these columns (3) are provided in the through-holes (30) of the terminals (30) provided on the first and second printed circuit boards (2) and (2a).
a), soldered and connected to each other, so that the first and second printed circuit boards (2),
The circuit pattern of (2a) is electrically connected via the pillar (3).

The plurality of columns (3) mechanically support the first and second printed circuit boards (2) and (2a), and the main body (1)
Mechanical strength,
Structural positional accuracy is required. Therefore, in the present invention, the pillars (3) are arranged at a plurality of positions substantially symmetrically along the periphery of the printed circuit boards (2) and (2a). With this configuration, the vertical strength between the first and second printed circuit boards (2) and (2a) can be obtained over the entire periphery of the two printed circuit boards (2) and (2a). The parallelism between the two printed boards (2) and (2a) can also be obtained with high accuracy. Furthermore, by arranging the column group (3a), which includes a plurality of columns (3) as a set, substantially symmetrically in the diameter direction (in the embodiment, disposed near the nut (29)), Even if the arrangement density of the pillars (3) other than the above is sparse, it can sufficiently counter the horizontal force such as twisting of the printed circuit boards, and also prevents the printed circuit boards from shifting in the horizontal direction. Printed circuit board (1),
(2) The error of the mounting position of the support can be eliminated.

(4) is an optical bench, (41) is a projection protruding from the center of the upper surface, (42) is a hook provided at a plurality of locations on the periphery, and (43) is a hook (12) of the main body (1). It is a locking portion provided as follows. (44) is a light emitting element such as a light emitting diode provided on the lower surface of the optical bench (4), (45) is a light receiving element such as a solar cell, and both receive light of the light emitting element (44) directly from the light receiving element ( Four
5) It is arranged so that it does not enter. Reference numeral (46) denotes a test light emitting diode provided to face the light receiving element (45), and light emitted from the light emitting diode directly enters the light emitting element (45). (47) is a cutout into which the confirmation light (28) provided on the first printed circuit board (2) is inserted, and (48) is a ring-shaped J-shaped partition wall provided on the periphery of the lower surface of the optical bench (4). The labyrinth (49) is an optical bench cover for covering the lower surface of the optical bench (4), and forms a dark box together with the labyrinth (48).

(5) an insect net wound around the optical bench (4);
(6) is a sensor cover, (61) is a smoke inlet, and (62) is an engaging portion provided on the upper edge of the inner wall corresponding to the hook (42) of the optical bench (4).

Next, an example of an assembling order of the present invention configured as described above will be described.

[1] Support IC (3) and hybrid IC standing upright
The first printed circuit board (2) on which the (21) and circuit elements (22) are mounted, and the MPU (25) and other circuit elements (2)
6) Prepare a second printed circuit board (2a) to which is attached.

[2] The first printed circuit board (2) is placed on the convex portion (41) of the optical bench (4), and the first printed circuit board (2) is placed from the labyrinth (48) side of the optical bench (4). The leads of the light emitting element (44), the light receiving element (45), and the test light emitting diode (46) are inserted into the through holes, and each is soldered to a circuit pattern. Next, the lens (45a) is replaced with the light receiving element (45).
Attach before.

[3] Attach the insect net (5) to the optical bench (4), and press-fit the optical bench cover (49) into the labyrinth (48).

[4] Solder the shield case (23) to the first printed circuit board (2), and lower the hybrid IC (21) so as to cover the shield case (23).

[5] The through holes (30a) of the terminals (30) of the second printed circuit board (2a) are fitted into the respective columns (3), and soldered.

[6] The electric circuit portions (the first and second printed circuit boards (2) and (2a)) of the assembled product assembled as described above are housed in the main body (1), and the optical table (4) The hook (12) provided on the lower edge of the main body (1) is engaged with the engaging portion (43) provided on the peripheral edge.

[7] Insert the two mounting screws (15) into the through holes (1
4) Insert the nut (2) of the second printed circuit board (2a)
9) and (29a), respectively, and fix the second printed circuit board (2a) to the main body (1).

[8] Cover the labyrinth (48) and the optical bench cover (49) with the sensor cover (6), and lock the engaging portion (62) of the sensor cover (6) with the optical bench hook (42).

 Adjustment after assembly is performed, for example, according to the following procedure.

[1] Insert a screwdriver into the through holes (17) and (27) provided in the main body (1) and the second printed circuit board (2a), operate the volume (24), etc., and operate the amplifier gain and test diode (46). Adjustment of the light emission amount, etc.) is performed.

[2] Set an address through the dip switch window (16).

[3] Attach a sticker for address display or inscription on the window hole (16) or through hole (17).

In the above description, an example in which the present invention is applied to a photoelectric smoke sensor is shown. However, the present invention can be applied to a semiconductor heat sensor and other sensors. Therefore, the main body, the optical bench, the labyrinth, the optical bench cover, the sensor cover, and the like are not limited to the above-described embodiment, and can be appropriately changed.

Further, the case where the first printed circuit board (2) is used for the sensor circuit and the second printed circuit board (2a) is used for the transmission circuit has been described. The case where the upper and lower parts are integrally joined is shown.
One or more printed circuit boards may be stacked by columns.

[Effects of the Invention] As is clear from the above description, in the present invention,
Since the plurality of pillars connecting the first and second printed circuit boards are densely arranged in at least one place, even if the pillars are sparsely arranged in other areas, it is like a twist between printed circuit boards. It can sufficiently counteract horizontal forces. Also,
As a result, the displacement in the horizontal direction can be prevented, so that it is possible to eliminate the error in the mounting position of the support of each printed circuit board.

In addition, since all or a part of the pillar is made of a conductive material, the pillar can be used as a connection line of a circuit pattern on the upper and lower printed circuit boards, and there is no need to separately wire the pillar.

Further, since the closely arranged struts are integrally connected by the binding device, the struts can be reinforced.

Also, the fire detection unit is attached to the surface of the first printed circuit board opposite to the element mounting surface.
The printed circuit board and the fire detection unit can be brought into close contact with each other. Therefore, the height of the fire detector can be reduced, and the whole can be made compact.

Further, since the second printed circuit board is fixed to the main body by a male screw member penetrating the bottom surface of the main body, the second printed circuit board can be easily fixed, and the first printed circuit board has a fixing portion to the main body. , It is possible to effectively utilize the board surface of the first printed board.
Further, the second printed circuit board is provided with a female screw portion, and it is only necessary to screw a male screw member into this female screw portion. Therefore, there is no need to provide a female screw portion for screwing the male screw member into the main body side. The internal space of the main body can be used effectively. Thereby, the main body can be downsized.

In addition, since the plurality of column assemblies connected by the binding device are arranged concentrically, even if a circumferential torsion force acts on the printed circuit board, the torsion force can be counteracted.
1. Distortion between the second printed circuit boards can be prevented.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of an embodiment of the present invention, FIG.
FIG. 3 is a plan view of the second printed circuit board with circuit patterns omitted, FIG. 3 is a bottom view of FIG. 1 showing a state where a cover is removed, FIG. 4 is a front view of the printed circuit board part of FIG. Fifth
Figure (a) is a plan view of an embodiment of the binding device, and (b) is a side view thereof. (1): body, (15): mounting screw, (2): first printed circuit board, (2a): second printed circuit board, (29): nut, (30): terminal, (3): support , (33): tying tool,
(4): optical bench, (5): insect net, (6): sensor cover.

Claims (3)

(57) [Scope of request for utility model registration] 1. A bottomed frame-shaped main body in which electric components and the like are housed, a first printed circuit board on which various elements are mounted on one surface, and a fire detection unit is mounted on the other surface, A second printed circuit board facing the element mounting surface of the first printed circuit board at a predetermined distance and being close to the bottom surface of the main body; and interposing between the first and second printed circuit boards. And a plurality of columns for coupling the first and second printed circuit boards. Part or all of the plurality of columns are electrically connected to an electric circuit pattern of the first and second printed circuit boards. The plurality of columns are densely arranged in at least one place, and the closely arranged columns are integrally connected with a binding member made of an insulating material to form a column assembly. A fire detector characterized by forming a body. 2. A method according to claim 1, wherein a female screw portion is provided on the second printed circuit board side, and a male screw member penetrating a bottom surface of the main body is screwed into the female screw portion to fix the second printed circuit board to the main body. 2. The method according to claim 1, wherein
The described fire detector. 3. The fire detector according to claim 1, wherein a plurality of column assemblies connected by the binding device are formed, and the plurality of column assemblies are arranged concentrically.