HU191704B - Clack serving for securing constant volume flow - Google Patents

Abstract

The present invention provides a flap for providing a constant volume flow, in which an automatically-locking closure is provided in the air channel section to the desired instantaneous throttle position. It is an object of the present invention to provide a ratio of 0 <m <0.4 d between the axis of rotation (4) of the closure (4) and the longitudinal symmetry axis (5) of the airflow section (1) perpendicular to the axis of rotation (4) (4) and the distance (k) between the inlet (6) of the closure (2) opposite the flow direction (7) and the rotation axis (4) is within the limits of (^ ♦ m) <Λ <2 (γ m), and the ratio of the exit edge (8) of the closure (2) to the flow direction (7) and the distance (1) between the rotation axis (4) to the distance (k) is 0.8 to 2.5. -1-

Description

(57) EXTRAS

The invention relates to a damper for providing a constant volume flow, whereby a self-adjusting shut-off member is incorporated in the duct section in a position corresponding to the desired instantaneous throttle state.

The object of the invention is that the ratio (m) between the axis of rotation (4) of the locking member (2) and the longitudinal axis of symmetry (d) of the duct section (1) perpendicular to the axis of rotation (d) is 0 <m <0.4 d. , and the distance (k) between the inlet edge (6) of the closure (2) facing the flow direction (7) and the axis of rotation (4) is within the limits (^ ♦ m) <Λ <2 (γ m), and the ratio of the exit edge (8) of the closing member (2) in the downstream direction (7) and the distance (1) between the axis of rotation (4) and the distance (k) is 0.8 2.5.

The present invention relates to a damper for providing a constant volume flow, whereby a shut-off member which automatically adjusts to the desired instantaneous throttle state is installed in the duct section.

When installing AHUs, there are many problems with adjusting the flow rates as planned, especially in multi-branched ducts, the desired flow rate can only be adjusted in several steps with lengthy work.

Conventional adjustment of a bayonet is usually done with a shutter or a butterfly valve. With its planned volumetric adjustment, the overhead line will behave as a passive ventilation element during its further operation, which is characterized by a resistance factor. If the supply pressure of the air duct changes relative to the control state (eg change of filter resistance, further control of other connected ducts, etc.), the resulting flow rate will be significantly different from the value previously set.

The listed drawbacks of conventional controls (cumbersome system control, volumetric flow, which varies significantly with the supply pressure) are addressed by active ventilation components.

Such an active element is the automatic butterfly valve of the TROX company, which keeps the flow rate practically constant, even when the supply pressure changes significantly. The torque generated by the flow forces acting on the butterfly valve rotating about the axis through the centerline of the duct is enhanced by the plastic foil bag attached to the lower pressure (back) side of the valve such that a greater pressure space is created through the bore through the valve or flap plate. The disadvantage of this solution is the vulnerability of the film and the risk of blocking of the through hole.

The air valve with axial blades also acts as an active control element, whereby the closing torque can be derived from the circumferential force generated by the air flowing through the blades. A control element of this design is also susceptible to contamination and is difficult to manufacture, especially at larger sizes.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a damper which maintains a constant flow rate of flowing air, even over a wide range of pressures, so that the structure is insensitive to contamination and easy to manufacture.

In view of this task, the inventive idea has been realized that, as usual, an asymmetrical positioning and design of the closure plate having an axis offset from the center line of the duct, e.g. a flap is used.

The object of the present invention is achieved by having a ratio of 0 <m <0.4 between the axis of rotation of the closure member and the longitudinal axis of symmetry of the duct section perpendicular to the axis of rotation, and the distance between the inlet edge and the axis of rotation * m) Within the range <k <2 (^ ni), and the ratio of the distance between the flowing edge of the closure member and the axis of rotation relative to the distance: 0.8 2.5.

Preferably, the desired flow rate can be adjusted either by counterweights placed on the lever fixed to the shaft of the closure or by varying the spring force of the spring connected to the lever fixed to the shaft of the closure.

Preferably, the duct section and the closure can also be used as fire dampers in a design with adequate fire resistance.

Advantages of the control device thus obtained compared to the previous designs:

- the flowing air is the closing element which produces the maximum hydraulically possible closing moment,

- the closure is not susceptible to soiling, or Aunt sensitive to reliable dusting,

- it is relatively easy to manufacture in any size.

DETAILED DESCRIPTION OF THE INVENTION The invention will be described in more detail with reference to the drawings, which illustrate an exemplary embodiment of the damper according to the invention.

Figure 1 is a longitudinal sectional view of the closure embedded in the channel section. .

Figure 2 is a front view of the closure member of Figure 1.

Figure 3 is a schematic diagram of the weight-adjusting mechanism of the closure member.

Figure 4 is a schematic diagram of a weight-loaded spring adjusting mechanism of the closure.

The principle structure of the control device according to the invention is shown in Figure 1. The pressure loss Δ p 'of the duct section 1, preferably of rectangular cross-section, is automatically varied by the flow-adapted closure member 2 so that the flow rate through it is kept constant. The locking member 2 may pivot about an axis 4 perpendicular to the flow direction in a bearing 3 located in two opposite side walls of the duct section 1. In the duct section 1, perpendicular to the axis 4, the closure member 2 is disposed such that the distance m between the axis 4 of the closure member 2 and the longitudinal axis of symmetry 5 of the duct section:

<ni <0.4 d.

The closure 2 is configured such that the distance k from the inlet 6 facing the flow direction 7 and the axis 4 lies within the boundaries ♦ m) <k <2 (| ♦ m) and the outlet edge 8 of the closure member 2 in the downstream direction 7 ratio of 1 distance between 4 axes for distance k:.

0.8 <y <2.5.

The locking member 2 can measure any angle turn φ up to the closing position ι / y, measured from its basic opening φ = 0 ° C. The instantaneous equilibrium of the closure member 2 at position adja is the result of the equilibrium between the closing torque M applied to the 4 axes by the hydraulic forces acting on the closure member 2 and the return torque M _{y for} the angular rotation φ. As the flow rate c changes, the magnitude of the torque also changes, which is

As a result of 191 704, the locking member 2 rotates about the axis 4 until, at the new angular rotation φ, the torques received on the axis 4 again equalize. The torque 5M is given by the combined torque derived from the counterweight 10 or the force exerted by the spring 11 and the dead weight of the closure member 2 on the lever 9 fixed to the shaft 4 of the closure 2 as shown in Figure 2 as a function of angular rotation. By appropriately selecting the M _y return torque, the damper can be set to different nominal controlled flow rates.

The damper can also perform a dual function in a single air duct: providing a constant flow rate and also serving as a fire damper if 8 structures are designed to meet fire resistance requirements.

The closure element 2 may be a straight sectional damper or an arcuate damper.

Claims (4)

PATENT CLAIMS A damper for providing a constant flow rate, wherein a shut-off member which is automatically pivoting in a position corresponding to the desired instantaneous throttle condition is incorporated in the air trunnion section, such that the pivot (2) is perpendicular to the axis of rotation the distance (m) between the longitudinal axis of symmetry (5) of the size (d) duct section (1) is 0 <ra <0.4 d, and the leading edge (6) of the closure (2) opposite the flow direction (7) and the axis of rotation The distance (k) between (4) is within the limits ^ ♦ m) <k <2 ^ m), and the distance (8) between the closing member (2) in the downstream direction (7) and the axis of rotation (4) 1) proportion to distance (k) The damper according to claim 1, characterized in that counterweights (10) are provided on the lever (9) fixed on the shaft (4) of the closure (2) for adjusting the desired flow rate. The damper according to claim 1, characterized in that a spring (11) with a variable force is coupled to a lever (9) fixed to the shaft (4) of the closure (2) for adjusting the desired flow rate. 4. A damper according to any one of claims 1 to 3, characterized in that the air channel section (1) and the closure (2) are made of refractory material. 2 drawing Published by. National Office of Inventions Responsible publisher: Zoltán Himer KODEX -3191.704 sj · International Classification Number: F 16 L55 / 10 - _____J F 1 Τ ' lr Fig. 2a