# US 4,398,697 A · Pivotal flap

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- Number: US 4,398,697 A
- Document ID: US4398697A
- Status: Granted
- Kind: A
- Application number: 06/266,510
- Filed: 1981-05-22
- Granted: 1983-08-16
- Earliest claimed: 1980-06-19
- Inventors: Hans-Jurgen Janich
- Web page: https://patentgrep.com/patent/US4398697A

## CPC

- F23L 13/02: pivoted about a single axis but having not other movement (formed as linked slats each pivoted about an axis F23L13/08)
- F16K 27/0218: {Butterfly valves}
- F23L: SUPPLYING AIR OR NON-COMBUSTIBLE LIQUIDS OR GASES TO COMBUSTION APPARATUS IN GENERAL ({air-supply arrangements for fluent fuels F23C;} firebridges with means for feeding air or steam F23M3/04; baffles or shields with air supply passages F23M9/04); VALVES OR DAMPERS SPECIALLY ADAPTED FOR CONTROLLING AIR SUPPLY OR DRAUGHT IN COMBUSTION APPARATUS {(dampers and throat restrictors for open fire-places F24; air inlet valves for open fire fronts F24)}; INDUCING DRAUGHT IN COMBUSTION APPARATUS; TOPS FOR CHIMNEYS OR VENTILATING SHAFTS; TERMINALS FOR FLUES
- F16K: VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING {(devices for emptying and evacuating the excess liquid in valves or conduits F16L55/07)}

## Abstract

The invention relates to a pivotal shut-off and control flap of which the central section (1) comprises an elongate shell (3) which at its two ends is fixedly connected to shaft elements (4) through hub members (6), provision being made for a limited relative movement between the shell and the vane section (2). In an arrangement such as this, the vane section does not undergo excessive deformation, even in the event of severe temperature stressing on one side. The torque required for operating the flap is uniformly transmitted to the vane section.

## Claims

### Claim 1

A rectilinear, pivotal shutoff control flap adapted for use in large, hot gas pipes comprises at least one mounting shaft rotatable about an axis; a pair of elongate vane sections extending longitudinally of said shaft and on opposite sides of said axis; and means connecting said vane sections to said shaft, said connecting means comprising at least one hub member fixed to said shaft, an elongate shell member carried by said hub member and extending longitudinally of said shaft, said shell member being of distortion resistant shape having opposite ends extending on opposite sides of said axis toward said vane sections and having a central section spaced transversely to one side of said axis and said shaft, and means coupling the opposite ends of said shell member to respective ones of said vane sections and enabling limited relative movement therebetween longitudinally of said shaft.

### Claim 2 (depends on 1)

A flap according to claim 1 wherein said shell member comprises a hollow member enclosing said shaft.

### Claim 3 (depends on 1)

A flap according to claim 1 wherein said shell member comprises an elongate plate and wherein said central section is dished to one side of said shaft.

### Claim 4 (depends on 1)

A flap according to claim 1 wherein said vane sections are coplanar with each other and with said axis.

### Claim 5 (depends on 1)

A flap according to claim 1 wherein said vane sections are coplanar with each other and offset to one side of said axis.

### Claim 6 (depends on 1)

A flap according to claim 1 wherein said connecting means includes a number of gusset plates secured to said shell member and to said hub member.

### Claim 7 (depends on 1)

A flap according to claim 1 wherein said coupling means comprises a plurality of bolts and wherein each of said vane sections has slots in which said bolts are accommodated, said slots extending in the longitudinal direction of said vane sections.

### Claim 8 (depends on 1)

A flap according to claim 1 wherein said vane sections are longer than and project beyond said shell member, and including fillers extending between those portions of said vane sections which project beyond said shell member.

### Claim 9 (depends on 1)

A flap according to claim 1 wherein said coupling means comprises low friction means.

### Claim 10 (depends on 1)

A flap according to claim 1 wherein said shell member is provided with spaced apart ventilation openings along its length.

### Claim 11 (depends on 1)

A flap according to claim 1 wherein the distance transversely of said flap between the coupling means of each of said vane sections and said axis is between 0.25 and 0.5 times the transverse width of said flap.