GB2186950A - Damper, e.g. for air conditioning - Google Patents

Abstract

Damper blades 4-6 are pivotally mounted in a frame 1. A control member 21 is rotatable to pivot the blades 4-6 via a worm gear in a gearbox 14. The angle of pivoting is indicated by a finger 16, moving over a scale 17, rigid with the worm wheel. The blades 4-6 are linked so as to pivot in synchronism, either in the same direction or in opposite directions. The worm wheel is rigid with the pivot of the middle blade 5; and the worm is rigid with an extension rod carrying the control member 21. <IMAGE>

Description

SPECIFICATION Damper, e.g. for air conditioning This invention relates to a damperforcontrolling air orgasflow, comprising one or more damper blades pivotally mounted in aa frame, and a control member which is rotatable to pivot the damper blade(s). Such a damper may be used for manual or automatic control of the airflow rate in a duct of an air conditioning installation,forexample.

In accordance with the present invention the control member is kinematicallyconnectedtothedamper blade(s) via a worm gear.

An advantage ofthis arrangement is that a worm gear can allow the damper blades to be turned by application of a low torque to the control member even when a strong air or gas flow is acting on the damper blades.

Preferably, the worm wheel ofthe worm gear is connected to an indicating meansforindicatingthe angle through which the worm wheel is turned, and hence indicating the degree of damping by the blade(s).

The invention will be described further, by way of example, with reference to the accompanying draw ings, inwhich: Figure 1 is a front view of a damper for use in an air conditioning installation, with damper blades all pivoting in the same direction; Figure 2 is a side view of the damper; Figure 3 is a front view of a damper with damper blades pivoting in opposite directions; and Figure4 is a sideviewofthe damper of Figure 3.

The damper illustrated in Figures 1 and 2 has a rectangularframe 1 with front and rearflanges 2 having punched holes 3, for connection by means of nuts and bolts to corresponding flanges on upstream and downstream sections of a duct of an air conditioning installation. Three damper blades4, 5, 6 are pivoted between sidewalls 7,8 of the frame 1 with their pivot axes paralled to the base wall 9. The blades 4-6 have brackets 11 pivoted to respective brackets 12 on a vertical link 13 which ensures that all the blades pivot in synchronism and in the same direction.

A gear box 14 accommodating aworm gears mounted on the outside ofthe sidewall 8. The worm wheel is rigid with the pivot axis of the middle blade5 and is also connected to an indicating finger 16 whose position can be read in conjunction with an angular scale 17 on the gear box 14. An extension rod 18, rigid with the worm oftheworm gear, is rotatably mounted parallel with the sidewall 8 by means of a bracket 19.

The free end of the rod 18 projects beyond the base wall 9 and carries a control knob 21 which is manually accessible without difficulty. The gearing down provided by the worm gear is such that the control knob 21 can be turned by hand evenwhen aforceful stream of air is passin-g overthe blades 4-6.

The damperillustratedin Figures 3 and 4 is similar to the damper described above, except that the upper and lower blades 4 and 6 pivot in the opposite direction to the middle blade 5. Forth is purpose a bracker22 on onesideofthe pivot axis of the middle blade 5 is connected by a linkage 23 to a bracket on the opposite side ofthe pivot axis of the upper blade4; and the upper and lower blades 4 and 6 are linked by brackets 11,12 and a vertical link 13 in the manner described above with reference to Figures 1 and 2.

Although the above-described dampers are shown with three blades, more orfewer blades can be used, depending onthe required size ofthe damper. The materials used in the construction of the damper, such as, for example, galvanised steel, stainless steel, mild steel, and aluminium, are selected in accordance with requirement of weight, wear resistance, corrosion resistance, fire resistance, and cost.

1. A damperfor controlling air or gas flow, comprising one or more damper blades pivotally mounted in a frame, and a control memberwhich is rotatableto pivot the damper blade(s), the control member being kinematically connected to the damper blade(s) via a worm gear.

2. Adamperasclaimed in claim 1, in which the worm wheel of the worm gear is connected to an indicating means for indicating the angle through which the worm wheel is turned.

3. A damper as claimed in claim 1 or2, in which the worm ofthe worm gear is rigid with one end of an extension rod on whose other end the control member is fixed.

4. Adamperasclaimed in claim 3, inwhichthe extension rod extends along one side of the frame, and the control member is manually accessible beyond one end of that side.

5. Adamperas claimed in any preceding claim, in which one ofthe damper blades is connected to the output of the worm gear by a pivot shaft, the remaining damper blade(s) being connected to the said one damper blade by a linkage so as to pivot synch ronously with it.

6. A damper as claimed in claimS, in which the linkage is so arranged thatthe blades all pivot in the same direction.

7. A damper as claimed in claimS, in which the linkage is so arranged that the pivoting ofthe said remaining blade(s) is in the opposite direction to the pivoting of the said one blade.

8. A damper substantially as described with refer enceto, and as shown in, Figures 1 and 2 or Figures3 and 4 ofthe accompanying drawings.

9. An air conditioning installation including an air duct provided with a damper according to any preceding claim.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (9)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Damper, e.g. for air conditioning This invention relates to a damperforcontrolling air orgasflow, comprising one or more damper blades pivotally mounted in aa frame, and a control member which is rotatable to pivot the damper blade(s). Such a damper may be used for manual or automatic control of the airflow rate in a duct of an air conditioning installation,forexample. In accordance with the present invention the control member is kinematicallyconnectedtothedamper blade(s) via a worm gear. An advantage ofthis arrangement is that a worm gear can allow the damper blades to be turned by application of a low torque to the control member even when a strong air or gas flow is acting on the damper blades. Preferably, the worm wheel ofthe worm gear is connected to an indicating meansforindicatingthe angle through which the worm wheel is turned, and hence indicating the degree of damping by the blade(s). The invention will be described further, by way of example, with reference to the accompanying draw ings, inwhich: Figure 1 is a front view of a damper for use in an air conditioning installation, with damper blades all pivoting in the same direction; Figure 2 is a side view of the damper; Figure 3 is a front view of a damper with damper blades pivoting in opposite directions; and Figure4 is a sideviewofthe damper of Figure 3. The damper illustrated in Figures 1 and 2 has a rectangularframe 1 with front and rearflanges 2 having punched holes 3, for connection by means of nuts and bolts to corresponding flanges on upstream and downstream sections of a duct of an air conditioning installation. Three damper blades4, 5, 6 are pivoted between sidewalls 7,8 of the frame 1 with their pivot axes paralled to the base wall 9. The blades 4-6 have brackets 11 pivoted to respective brackets 12 on a vertical link 13 which ensures that all the blades pivot in synchronism and in the same direction. A gear box 14 accommodating aworm gears mounted on the outside ofthe sidewall 8. The worm wheel is rigid with the pivot axis of the middle blade5 and is also connected to an indicating finger 16 whose position can be read in conjunction with an angular scale 17 on the gear box 14. An extension rod 18, rigid with the worm oftheworm gear, is rotatably mounted parallel with the sidewall 8 by means of a bracket 19. The free end of the rod 18 projects beyond the base wall 9 and carries a control knob 21 which is manually accessible without difficulty. The gearing down provided by the worm gear is such that the control knob 21 can be turned by hand evenwhen aforceful stream of air is passin-g overthe blades 4-6. The damperillustratedin Figures 3 and 4 is similar to the damper described above, except that the upper and lower blades 4 and 6 pivot in the opposite direction to the middle blade 5. Forth is purpose a bracker22 on onesideofthe pivot axis of the middle blade 5 is connected by a linkage 23 to a bracket on the opposite side ofthe pivot axis of the upper blade4; and the upper and lower blades 4 and 6 are linked by brackets 11,12 and a vertical link 13 in the manner described above with reference to Figures 1 and 2. Although the above-described dampers are shown with three blades, more orfewer blades can be used, depending onthe required size ofthe damper. The materials used in the construction of the damper, such as, for example, galvanised steel, stainless steel, mild steel, and aluminium, are selected in accordance with requirement of weight, wear resistance, corrosion resistance, fire resistance, and cost. CLAIMS

1. A damperfor controlling air or gas flow, comprising one or more damper blades pivotally mounted in a frame, and a control memberwhich is rotatableto pivot the damper blade(s), the control member being kinematically connected to the damper blade(s) via a worm gear.

2. Adamperasclaimed in claim 1, in which the worm wheel of the worm gear is connected to an indicating means for indicating the angle through which the worm wheel is turned.

3. A damper as claimed in claim 1 or2, in which the worm ofthe worm gear is rigid with one end of an extension rod on whose other end the control member is fixed.

4. Adamperasclaimed in claim 3, inwhichthe extension rod extends along one side of the frame, and the control member is manually accessible beyond one end of that side.

5. Adamperas claimed in any preceding claim, in which one ofthe damper blades is connected to the output of the worm gear by a pivot shaft, the remaining damper blade(s) being connected to the said one damper blade by a linkage so as to pivot synch ronously with it.

6. A damper as claimed in claimS, in which the linkage is so arranged thatthe blades all pivot in the same direction.

7. A damper as claimed in claimS, in which the linkage is so arranged that the pivoting ofthe said remaining blade(s) is in the opposite direction to the pivoting of the said one blade.

8. A damper substantially as described with refer enceto, and as shown in, Figures 1 and 2 or Figures3 and 4 ofthe accompanying drawings.

9. An air conditioning installation including an air duct provided with a damper according to any preceding claim.