DD151214A1 - COUNTERPROOF TAILGATE BUTTON FOR AUTOMATIC LOCKING OF AN AIR DRAINAGE DIRECTION - Google Patents

Abstract

The invention relates to a gegenlaeufige check valve for self-locking a Luftstroemungsrichtung in ventilation or air conditioning systems, both for horizontal and vertical Luftfuehrung, in which the flow direction can be selected by appropriate installation position either up or down, can be used. It opens automatically at a pressure difference in the flow direction. Here are two highly eccentrically mounted and mechanically coupled in the opposite direction of rotation flap plates open the Oeffnungsquerschnitt from the center. In the fully opened state, the flap plates with minimal flow resistance are parallel in the air flow. At standstill of the system or part of the system, the flap closes automatically and locks with high tightness the opposite flow direction. By applying an additional torque to the damper axis, the flow characteristics can be adapted to other conditions of use. The invention replaces Stellmotorbetaetigte butterfly valves with OPEN-CLOSE function or in special cases, those with control function including the associated control circuits.

Description

Title of E rf i no 'υ ng

Opposite non-return flap for the automatic blocking of an air flow direction

Application field of Fiction ndu ng

The invention relates to an opposing non-return valve for the automatic blocking of an air flow in ventilation or air-conditioning systems, especially in fluidic combination with fans or as a replacement of a power-assisted valve with OPEN-CLOSE function.

Characteristic of the known technical solutions

It is known to use in air conditioning and air conditioning systems to block a flow direction and to prevent the ingress of false air butterfly valves that are operated by hand or by actuator with open-close function.

This device requires additional operating effort, or considerable effort on control or regulation.

In addition, has a special butterfly valve due to its large sealing edge length. Leakage losses that can no longer be neglected »

It is also known to use the self-opening and closing overpressure flap for blowing out air into the open air or for differential pressure compensation in a flow direction. In this component flap plates, which are slightly curved and are stored right and left at the respective upper edge in the frame, pushed in the air flow until they abut a stop web. When the system is at a standstill, they hang back into their original position due to their own weight and thus block the opposite direction of flow. Due to the structurally required limitation of the opening angle of the flap plates, the air flow is deflected strongly downwards, which leads to a disadvantageous high flow resistance. The individual folding

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pen sheets are mechanically very sensitive and prone to failure and, depending on the width, only hold back against

2 ner- 500 N / m stood.

It is also known to use for blowing air into the open air, in particular after axial fans for exhaust air, the axial fan door. It opens automatically in the air flow and closes again when the fan stops. It consists of two narrow overlapping flap plates arranged one above the other. The upper flap plate is mounted on the upper edge, the lower on the lower edge with a horizontal axis on the vertical frame outer surface in an attached sleeve. On the inside of the damper, a long lever is mounted vertically on the lower damper plate and a short lever on the upper damper. By means of a pull rod, the two levers are connected to each other via two joints that the flap plates can open from the center in the flow direction and go through Schvverkrafteinfluß alone again. They lie in the "CLOSE" position on the outside of the frame • 20 and block the opposite direction of flow.

Due to the different length levers there is no synchronism between the upper and lower flap plate. The air outlet angle is different at each flap opening angle.

The maximum gap width between the flaps. Blechen corresponds to about half of the nominal height of the axial fan door. Due to this strong Querschnittsseinschnürung occurs a high flow resistance. Further opening is not possible in principle, since otherwise the pivot point of the lower lever tilts over the dead center and blocks the flap in the open state. The connecting linkage in the air flow is maintenance-intensive and difficult to access

 The axial fan damper can only be used for horizontal air flow and is not suitable for duct installation.

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It has already been proposed a round fan door with air duct from top to bottom, consisting of 2 semicircular flap plates, which are rotatably mounted on a rod lying in diameter and are automatically closed by counterweights at standstill of the fan.

In the case of this invention, in the half-open state with turbulent flow, uncontrolled rocking motion can occur due to the glancing of the independently oscillating flap halves, which in turn can adversely affect the uniformity of the flow.

Purpose of the invention

The invention serves the purpose of achieving a reduction of the control or control technical effort in the automatic blocking of an air flow direction in ventilation and air conditioning systems.

Wese n the invention

The object of the invention is an automatic counter-rotating non-return valve, which opens in the air flow, has a minimal flow resistance in the operating mode without significant flow direction deflection and in the off state of the system or a subsystem safely and with minimal leakage locks the opposite flow direction or avoids false air inlet in both flow directions. It should be functional for the same basic concept in horizontal and vertical air flow, in which the flow direction can be up or down

 Your maximum flow resistance as a function of the flow velocity and the flap opening angle should be largely adapted to the requirements of the air technical system.

The flap should be suitable for installation between channels or other basic building units and for free blowing.

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The flap plates should be quiet in the air flow even with uneven flow. The flap should have a low maintenance.

Features of the invention

According to the invention, the object is achieved in that two narrow overlapping superimposed flap plates, of which the upper strongly eccentric parallel to its upper edge, the lower tap in the same division ratio parallel to its lower edge by means of bearing IQ, on which they in the flow direction before be screwed on the axis, are movably mounted in a square U-shaped frame. Two equal-length levers, which are attached to the protruding from the frame upper and lower axis are movably coupled by a tie rod with bearings so that the flap plates can open in the opposite direction from the center in the flow direction.

The lever and tie rod length relative to the axial distance and the angular position of the lever relative to the flap plates are coordinated so that over the entire adjustment range, the angular movement of the upper and lower axis is largely synchronous, thereby cancel the caused by the flap plate weight torques approximately mutually and the In the fully opened state, flap plates lie parallel to one another and to the horizontal frame surface.

The dead weight of a flap component causes the required torque for self-closing when the system is at a standstill due to leverage. "It is designed as the optimum between functional reliability and minimum flow resistance. The higher the weight, the greater the moment in the direction of slipping and the safety against slipping of the flap plates by increasing the bearing friction due to wear and contamination, but the higher the flow resistance of the flap increases.

By attaching a, additional weight to another lever which can be mounted on the axis at any angle, the vertical flow direction up or down can be realized with the same basic concept of the flap in addition to the horizontal air flow direction, wherein in all positions of use the fluidic properties Targeted weight selection and lever angle position relative to the flap sheet can be varied *

EXECUTIVE EXAMPLES

The invention will be explained in more detail below using an exemplary embodiment. In the accompanying drawing show:

Fig. 1: the side view of fully opened flap plates

Fig. 2 :. the side view in section with closed flap plates

Main components of the opposing check valve are the frame 1, the upper flap plate 2 and the lower

Flap plate 3, The upper flap plate is highly eccentric and parallel to its upper edge, the lower mounted in the same division ratio parallel to its lower edge by means of bearing pins movable and smooth in the frame.

Depending on the size and permissible maximum pressure difference, the flap plates can be provided with stiffeners. In the frame, the stop angle 4 are fixed to the side, on which the flap plates tightly rest in the closed state and also prevent the opening of the flap plates with back pressure in the opposite direction.

At the top and bottom are outside the frame. depending on flap size on one side or mutually equal levers 5 attached, which are connected by means of a tie rod 6 with bearings so that the flap plates in the opposite sense to parallelism with each other

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and opposite the horizontal frame surface can open.

function Weiser

When there is a pressure difference in the opening direction, the flap plates pivot out of the rest position. Due to the mechanical coupling, they are also in the partially opened state quietly in the air flow. From a certain flow rate, they are fully open.

When switching off the air flow is in this standard IQ execution of the counter-rotating check valve required for the "automatic closing of the damper plates torque that must overcome the bearing friction safely generated by the weight of the coupling linkage.

Additional functional reliability receives the flap in that the beginning of air return flow, the closing movement of the flap plates is supported. When closed, the flap plates seal well at their central overlap and laterally at the stop angles.

It is estimated that the counter-rotating check valve operates under normal conditions several years maintenance-free. Once maintenance is required, it is easy to do with the outside linkage linkage.

One application of this standard version of the opposing check valve consists z. B. in the parallel arrangement of two or more fans of the same or different nominal size for arbitrarily graduated air flow promotion in a common system. The fan is followed by a corresponding counter-rotating non-return flap instead of an actuating-motor-operated control flap, which automatically opens fully when the fan is operating, when the fan is at a standstill.

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is closed and compared to the static pressure difference by the other running fans has sufficient stability and low leakage.

The fluidic properties and the number of mounting positions can be meaningfully extended by the action of defined additional torques on the damper axles.

On one or both axes, depending on the required moment one or both sides by means of horizontally located lever 6, an additional weight 7 is mounted so that it acts in the closing direction of the flap. By varying the size of the weight or length of the lever, a variable differential pressure across the flap can build up before it begins to open after exceeding the maximum static pressure difference. With increasing opening angle oC , the momentum is reduced by reducing the projected lever length, in the open state, ie at cC «90 °, the additional weight is ineffective and the flap has its original low flow resistance. This application is shown in FIG.

If the flow velocity in the specific application is insufficient to fully open the flap even without a counterweight, the attachment angle / 3 of the lever can be selected such that the counterweight likewise reaches the top dead center at the maximum opening angle α which can be reached in the operating state , d, h. ß is equal to oC .

A stop prevents the counterweight from tipping over the top dead center.

One application of this variant - standard version with additional torque in the closing direction - is z. B.

in use as an external air damper with OPEN-CLOSE function instead of a servo-actuated damper in front of an outdoor air ventilator with a closed duct system between damper and fan. When the system is at a standstill, the flap is closed and remains tightly closed even when there is wind load against the flap sheet surface. Only at the start of the

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Fan opens sic-h the flap after reaching the maximum differential pressure automatically, when the fan expires, the flap closes at a relatively lower differential pressure. Through this hysteresis, the flap works with a smooth course of movement.

The counter-rotating non-return valve is also suitable for horizontal installation. In the case of the air duct upwards, in the standard version, the dead weight of the flap causes the build-up of a differential pressure before it opens. When fully opened, it has approximately the same low flow resistance as horizontal airflow. A stop prevents the flap plates from opening beyond the parallel position and tilting above the top dead center. The closing moment is now caused by the weight of the vertical flap plates, which are arranged with the radius of the journal as a lever to each other lying.

Possible applications exist, for example, as exhaust air damper under roof fans. The flap opens when the fan starts and automatically closes at the outlet of the fan against the pressure difference by the existing natural buoyancy and thus prevents the cooling of a room by free convection.

If, in addition, the counterweight on a lever with an angle .beta. Between 0 and 90 is allowed to act as the closing moment, then the differential pressure before opening the flap can be increased and also adjusted so that it remains approximately constant until the flap is almost fully opened , ,

Application of this fluidic property consists z. B. in use as an automatic bypass valve instead of a control loop with sensor and actuator-operated control valve to keep constant the pressure in a main channel at a constant air flow rate and variable air volume decrease various individual systems,

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Allowing the counterweight to act on a lever with an angle between 90 and 180, so it partially compensates for the increased closing torque caused by flap plate weight, and it is a minimum flow resistance over the entire adjustment range realizable. Application example analog standard version.

When installed horizontally, with air guide down must be so dimensioned the counterweight and mounted to secure the operability that the fully compensated and in the opening direction acting moment by the own weight of the flap additionally applying a safe replacement to overcome the bearing friction torque.

Application of this installation variant is z. B. as a replacement of an outside air damper with servomotor and open-close function with air flow from above into an air conditioning system.

Instead of a weight on the lever spring force can in principle be used to achieve the automatic closing and adjust the pressure difference as a function of flow velocity within wide limits the requirements äer air technical system.

The standard version of the counter-rotating non-return valve can also be used with vertical axes for horizontal air flow. The time required for automatic closing must by spring force z. B. between a fixed point on the flap frame and the pull rod or by weight over deflection , z, B. pulley, are applied. By selective selection of weight and lever arrangement, the pressure difference as a function of the flow velocity can be adapted in this mounting position special applications,

Possible application z. B. when used as an air distributor to achieve an approximately constant throw

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load-adapted, variable volume flow through a self-adjusting gap width between the flap sheets.

In the speed range up to the complete opening of the flap plates, the flap angle is speed-dependent. This property can be approximated by measuring angle and comparison with a fluidically measured flap of the same construction and size for measuring the flow velocity in all installation positions described.

In order to increase the accuracy of the display, it is possible to spread the region of interest by means of targeted torque action on the flap axis.

Application exists z. In plant adjustment and monitoring.

Claims (2)

2 19 1 69 Introduction 1. Opposing non-return valve for automatically blocking an air flow direction in ventilation and air conditioning systems with rectangular frame in which two abutting arranged flap plates, wherein the upper flap plate at its upper and lower flap plate at its lower edge arranged by means of axes movable and with outside The air flow lying adjusting device are mechanically coupled so that they open by differential pressure in the flow direction from the center in the opposite sense, automatically shut down in case of plant standstill by gravity and lock the opposite flow direction, characterized in that on the protruding from the frame axes against each other staggered levers are fixed rigidly, which are connected at its other end with the angularly movable and in length with respect to the axial distance of the flap plates' tuned pull rod, so that the flap Move nbleche with approximately synchronous angular movement, in the open state parallel to each other and to the horizontal frame surface and close by dead weight of the components or a vafiierbares additional weight on the adjusting device again. 2. Opposite non-return valve according to claim 1, characterized in that the torque of an attached to the axis with angle-adjustable variable variable additional weight the Schließmornent the flap plates so influenced that the vertical air flow can be realized with flow direction up or down at horizontally juxtaposed flap plates. For this purpose 1 ropes drawings