JPH0542038B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a cover fitting structure for a smoke detector for removably attaching an outer cover to a sensor body.

(Prior Art) Conventionally, as a structure for fitting an outer cover to a sensor main body, for example, the structure shown in FIG. 8 is known.

In FIG. 8, 100 is the sensor body;
An outer cover 102 is detachably attached to the lower side of the sensor body. As a cover fitting structure for this purpose, a plurality of fitting pieces 103 extend from the fitting side periphery of the outer cover 102, and a fitting groove 104 that opens on the right side is formed in the fitting pieces 103. . on the other hand,
On the sensor main body 1 side, a circumferential fitting protrusion 105 is formed on an inner wall that is a fitting position.

Therefore, when the outer cover 102 is fitted into the sensor body 100 and turned clockwise, the fitting groove 1 of the fitting piece 103
04 can fit into the fitting protrusion 105 on the main body side.

(Problems to be Solved by the Invention) However, in such a conventional fitting structure, since the structure is such that the fitting is rotated after fitting, there is a need for fitting on the sensor main body 1 side. The space becomes larger, which increases the size of the sensor body.Furthermore, since it can be easily removed by turning it in the opposite direction after fitting, there is a risk that the outer cover may be removed by mischief or the like.

Furthermore, when the outer cover is removed, the internal detection section is affected by ambient light and the like, resulting in false alarms.

(Means for Solving the Problems) The present invention has been made in view of such conventional problems, and it reduces the fitting space on the sensor main body side, and also facilitates removal after fitting. It is an object of the present invention to provide a cover fitting structure for a smoke detector that prevents smoke detectors from being exposed.

In order to achieve this object, the present invention provides a sensor cover fitting structure in which a cap-shaped cover member is removably fitted to the sensor main body.
A T-shaped fitting piece is protruded from the fitting side peripheral edge of the cover member, a fitting hole having a slit-like opening is formed at a fitting position of the sensor main body opposite to the fitting piece, and The inner wall surface of this fitting hole is provided with a wedge-shaped engagement protrusion tapered higher than the insertion side to which the T-shaped tip of the fitting piece is engaged.

(Function) According to the cover fitting structure of the present invention,
It can be fitted by simply fitting the cover member into the sensor body, and there is no need to turn it to fit it after fitting it as in the conventional case, so the fitting space on the sensor body side can be fitted by turning it. It is possible to save money by the amount that does not match, and the sensor itself can be made smaller.

Furthermore, in the fitted state, the T-shaped tip of the fitting piece on the cover side is engaged with the wedge-shaped engagement protrusion formed in the fitting hole of the sensor body, and this engaged state cannot be seen from the outside. Since the cover member cannot be easily removed even if an attempt is made to remove the cover member, it is possible to reliably prevent the cover from being removed due to mischief or the like.

(Example) FIG. 1 is an exploded view of a smoke detector equipped with a cover fitting structure of the present invention.

In FIG. 1, reference numeral 1 denotes a main body cover on the sensor main body side. A smoke detection section 4 with an insect screen 3 attached to the outer side of the peripheral wall having a labyrinth structure is installed in the storage section 1a opened on the lower side of the main body cover 1 through a shield case 2. 4 is fixed to the fitting fitting 5 on the upper part of the main body cover 1 by screwing a screw 6 from below. Further, a printed circuit board 30 on which a sensor circuit is mounted is installed between the shield case 2 and the smoke detection section 4.

Also, inside the smoke detection section 4, a light emitting holder 7 containing a light emitting element and a light receiving holder 8 containing a light receiving element are provided.
are provided, a light emitting holder 7 and a light receiving holder 8
Holder covers 9 and 10 are attached to each of them, and a shield cap 11 is attached to the light receiving unit holder 8, respectively.

Following such a smoke detection part 4 is a smoke detection part cover 1.
An outer cover 13 is detachably attached to the main body cover 1 with the outer cover 2 interposed therebetween.

FIG. 2 is a plan view of the outer cover 13 shown in FIG. 1 taken out and viewed from below, and FIG. 3 is a side view thereof.

In FIGS. 2 and 3, the outer cover 13 has a cap-like cover shape, and has a plurality of smoke inlets 14 opened on the tapered peripheral side, and as is clear from FIG. Three fitting pieces 15 having T-shaped tips protrude from the periphery on the fitting side.

FIG. 4 is a plan view of the main body cover 1 shown in FIG. 1 viewed from below, and shows a slit-shaped opening along the circumference of the peripheral wall opening of the storage section 1a that houses the smoke detection section 4. A fitting hole 16 is formed through the back side.

This fitting hole 16 is shown in the enlarged plan view in FIG. 5, in FIG. 6 showing the AA cross section in FIG.
As is clear from FIG. 7 showing cross-section B, a wedge-shaped engagement protrusion 17 is provided on the inner wall of the fitting hole 16, tapering upward from the insertion side. When the illustrated fitting piece 15 of the outer cover 13 is pushed in, the T-shaped tip of the fitting piece 15 passes over the wedge-shaped engagement protrusion 17 and fits into the stepped portion 18 at the lower end of the wedge-shaped engagement protrusion 17. This will prevent it from falling out.
Furthermore, the width W1 of the fitting hole 16 is set in a relationship such that W1≧(2×W2) with respect to the thickness W2 of the fitting piece 15 of the outer cover 13 shown in FIGS. The height of the wedge-shaped engaging protrusion 17 provided in the matching hole 16 is the same as that of the outer cover 13.
The dimension is approximately equal to the thickness W1 of the fitting piece 15.

Next, the operation of the above embodiment will be explained.

First, the outer cover 13 is attached to the main body cover 1 on the sensor main body side in FIG. When the fitting piece 15 of the outer cover 13 is aligned and pushed into the hole 16, the fitting piece 15 of the outer cover 13 fits into the fitting hole 16 formed in the main body cover 1, and further the outer cover 13 When pushed in, the T-shaped tip of the fitting piece 15 will
As shown in FIG. 7, the outer cover 13 is fitted onto the main body cover 1 by passing over the engagement protrusion 17 formed in the fitting hole 16 and fitting into the stepped portion 18 .

On the other hand, the removal after fitting the outer cover 13 is as follows.
Even if you try to remove the outer cover 13 from the outside, the T-shaped tip of the fitting piece 15 will not fit into the engagement protrusion 1 of the fitting hole 16.
Since it is fitted into the stepped portion 18 of No. 7, it cannot be easily removed.

To remove this outer cover 13, for example, push a small flathead screwdriver from the back side of the main body cover 1 into the base of the fitting piece 15, push it outward, and insert the T-shaped tip of the fitting piece 15 into the fitting hole 16. It can be removed by removing it from the engagement protrusion 17.

Therefore, the outer cover cannot be easily removed when the sensor is mounted on the ceiling.

(Effects of the Invention) As described above, according to the present invention, in a sensor cover fitting structure in which a cap-shaped cover member is removably fitted to a sensor main body, the fitting side periphery of the cover member A T-shaped fitting piece is protruded from the part, a fitting hole with a slit-shaped opening is formed at the fitting position of the sensor body opposite to this fitting piece, and a fitting hole is formed on the inner wall surface of the fitting hole. Since a wedge-shaped engagement protrusion tapered from the insertion side to which the T-shaped tip of the fitting piece is engaged is provided, the cover member can be fitted to the sensor body simply by fitting it. Since there is no need to turn the sensor to fit it after fitting as in the conventional case, the fitting space can be saved by not having to turn the sensor, and the sensor main body can be made smaller.

In addition, in the fitted state, the T-shaped tip of the fitting piece on the cover side is engaged with the wedge-shaped engagement protrusion formed in the fitting hole on the sensor body side, so this engaged state can be detected from the outside. Therefore, even if you try to remove the cover member when the sensor is attached to the ceiling, it will not be possible to remove it easily.This will surely prevent the cover member from being removed due to mischief, etc., and will prevent the cover from being removed. It is possible to prevent false alarms caused by

[Brief explanation of the drawing]

Fig. 1 is an exploded view of a smoke detector equipped with the cover fitting structure of the present invention, Figs. 2 and 3 are explanatory views of Fig. 1 with the outer cover removed, and Fig. 4 is the same as Fig. A plan view with the main unit cover removed, Figure 5 is the 4th
An enlarged explanatory view of the fitting hole in the figure, Figure 6 is A- in Figure 5.
A sectional view, Fig. 7 is a BB sectional view of Fig. 5, Fig. 8
The figure is an explanatory diagram showing a conventional example. 1: Main body case, 2: Shield case, 3: Insect screen, 4: Smoke detection part, 5: Fitting metal fittings, 6: Screws,
7: Light emitting holder, 8: Light receiving holder, 9,1
0: Holder cover, 11: Shield cap, 1
2: Smoke detector cover, 13: Outer cover, 14: Smoke inlet, 15: Fitting piece, 16: Fitting hole, 17: Engagement protrusion, 18: Step part.

Claims (1)

[Scope of Claims] 1. In a sensor cover fitting structure in which a cap-shaped cover member is removably fitted to a sensor main body, a T-shaped fitting is provided from a peripheral edge of the fitting side of the cover member. A plurality of fitting pieces protrude, a fitting hole with a slit-shaped opening is formed at a fitting position of the sensor main body opposite to the fitting piece, and a T in the fitting piece is formed on the inner wall surface of the fitting hole. A cover fitting structure for a smoke detector, characterized in that a wedge-shaped engagement protrusion tapered from the insertion side to which the tip of the letter-shaped tip is engaged is provided.