JPS5825515Y2 - fire detector - Google Patents

Description

[Detailed description of the invention] This invention relates to a fire detector that is lined with a shield plate inside the container that serves as both fire resistance and electrical shielding.The purpose of this invention is to reduce the number of parts used and to ensure that the shielding It is to provide fire detectors where the fire occurs.

FIG. 1 shows a conventional fire detector, in which a lead wire 5 is used to conduct electricity between a cover 2 lined with a shielding material 1 and a base 4 also lined with a shielding material 3, between the shielding materials 1 and 3. After connecting, connect the cover 2 and base 4 with screws 6, 6.
However, the lead wire 5
It is not easy to connect, and it is a very difficult tightening work to close the lid and tighten the screws 6, 6 in that connected state.
In addition, in order to tighten the screws 6, 6, it is necessary to form long protrusions 7, 7 on the cover 2, but generally such long protrusions 7, 7 are formed in plastic molding of synthetic resin materials.
It is not preferable to integrally form the protrusion 7 due to problems in terms of efficiency and quality, and there are also drawbacks such as the protrusion 7 being easily damaged by tightening the screw 6.

This invention was made in view of the above reasons.

Hereinafter, an embodiment of the fire detector of the present invention will be described with reference to FIG. 2, in which the same parts as in the conventional example are given the same reference numerals.A shielding material 3 is lined with a surrounding wall 8 that protrudes downward on the outer periphery. A base body 4 having an engaging element 9 protruding inwardly from the surrounding wall 8 and a sensing chamber portion 10 attached below the shield material 3; and a mouth edge portion that fits into the surrounding wall 8. From the cover 2, which has an engaging element 12 protruding from the outer wall of the base body 4 to engage with the engaging element 9 of the base body 4, a sensing chamber 14 having a smoke introduction hole 13 in the center, and an inner surface lined with a shielding material 1. The shield material 3 of the base body 4 forms a downwardly curved spring portion 15 on the outer peripheral edge, and the shield material 1 of the cover 2 also forms a spring portion 15 bent downward.
The fire detector has its outer peripheral edge 16 pressed against the spring portion 15.

In addition, 17 is a small protruding pillar that locks the shield materials 1 and 3,
18 is a printed board 1 to which a sensing chamber portion 10 is attached using a retaining piece.
9 is a locking device, 20 is a radiation source, 21 is a smoke blocking plate,
22 is an introduction hole to the ion chamber, 23 is a removal groove formed between the inner wall of the surrounding wall 8 and the outer wall of the mouth edge 11, and 24 is a removal tool.

Thus, the opening edge 11 of the cover 2 is placed inside the surrounding wall 8 of the base 4.
When they are inserted and fitted, the engaging element 9 and the engaging element 12 are engaged as shown in the figure.

In this state, the spring portion 1 of the shielding material 3 lined with the base 4
5 is in pressure contact with the outer peripheral edge 16 of the shield material 1 of the cover 2.

The reaction force caused by this acts in the direction of opening the space between the base body 4 and the cover 2. Therefore, the two protruding engaging elements 9 and 12 are also pressed together in the closing engagement direction by the reaction force. Therefore, in the present invention, the base body 4 and the cover 2 are
At the same time as the combination, the mutual shielding materials 1 and 3 are electrically connected to ensure electrical shielding, and the bonding between the base body 4 and the cover 1 without wobbling is ensured.

As described above, the shield material 3 is lined with a surrounding wall 8 that protrudes downward on the outer peripheral edge, and the engaging element 9 is provided inwardly to project from the surrounding wall 8, and the sensing chamber component 10 is provided below the shield material 8. An engaging element 12 that engages with the engaging element 9 of the base body 4 is provided protruding from the outer wall of the mouth edge part 11 that fits into the surrounding wall 8, and smoke is introduced into the central part. The cover 2 has a sensing chamber 14 having a hole 13 and is lined with a shielding material 1 on the inner surface. The shield material 1 has its outer peripheral edge 16 connected to the spring portion 15.
By making the fire detector in pressure contact with the lead wires, the electrical connection of the shielding materials 1 and 3 and the connection of the base body 4 and the cover 2 can be made without using the conventional lead wires 5 and screws 6. It is possible to ensure a reliable connection and connection without the risk of cutting like the wire 5, and without the risk of loosening like a screw, which is advantageous in manufacturing and reduces the required materials and lowers the price.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional front view showing a conventional fire detector, and FIG. 2 is a cross-sectional front view showing an embodiment of the fire detector of the present invention. DESCRIPTION OF SYMBOLS 1... Shielding material, 2... Curved cover, 3... Curved shielding material, 4... Base, 8... Enclosing wall, 9... Hitting/engaging element, 11... ...rim of mouth, 12...
...Engager, 15...Bent spring part, 16...
The outer periphery.

Claims (1)

[Scope of utility model registration request] a base body lined with a shielding material, forming a surrounding wall protruding downward on its outer periphery, an engaging element projecting inward of the surrounding wall, and a sensing chamber attached below the shielding material; A cover in which an engaging element that engages with the engaging element of the base body is protruded from the outer wall of the mouth edge that fits into the surrounding wall, a sensing chamber having a smoke introduction hole is formed in the center, and the inner surface is lined with a shielding material. The shielding material of the base has a downwardly curved spring portion on its outer periphery, and the shielding material of the cover has its outer periphery pressed into contact with the spring portion.