Fireproof smoke damper

• US 3,912,223 A
• Filed: 03/15/1974
• Issued: 10/14/1975
• Est. Priority Date: 03/15/1974
• Status: Expired due to Term

• Current Assignee: Yoshiaki Iwata
• Original Assignee: Yoshiaki Iwata
• Inventors: Iwata, Yoshiaki
• Primary Examiner(s): Wayner, William E.
• Assistant Examiner(s): Yuen, Henry C.
• Application Number:
  US05/451,343
• Time in Patent Office: 578 Days
• Field of Search: 98/1,58-62,108 126/285R,285B,287.5,293,285.5,292,297,289 251/30,299,298,303,300 236/49 169/60,61,65,5
• US Class Current: 251/299
• CPC Class Codes: A62C 2/12 Hinged dampers
• CPC Class Codes: F16K 17/386 the closure members being rotatable or pivoting

Abstract

A fireproof smoke damper having a casing or duct which includes a curved sector and a shutter plate within the sector and pivoted at the center of curvature thereof.

Claims

1. A fireproof smoke damper assembly comprising a duct having a substantially straight section and a curved elbow section joined one to the other, said curved section having a longitudinal section in the form of a sector of a circle having its center at one side of said duct, a shaft on said one side of said duct and substantially coincident with said center and a damper plate attached along one edge to said shaft for rotation within said duct about said center, said damper being movable from an open position lying against a wall of said straight section to closed positions when disposed at any point within said curved section and is in close proximity with the wall of said curved section.

2. A fireproof smoke damper according to claim 1 including an arm carried by said shaft, a cylinder including a spring loaded piston, a rod coupling said arm to said piston whereby said piston under the action of said spring will normally hold said damper in the closed position, means including an electrically operated valve for feeding a fluid under pressure to said cylinder, said valve upon being energized permitting fluid pressure to act on said position and move it in opposition to said spring to open said damper and means on said valve for interrupting said fluid pressure upon de-energization and permit discharge of said fluid in said cylinder and said piston to move said damper to the closed position.

3. A fireproof smoke damper according to claim 2 including a power switch, a thermostatically controlled switch and at least one test switch connected in series one with the others and with said electrically operated valve for controlling the application of energy to said valve.

4. A fireproof smoke damper according to claim 3 wherein a heat responsive fuse is positioned within said damper casing and connected in series with said switches.