FI60069B - FOERFARANDE OCH ANORDNING FOER KONSTANTHAOLLNING OCH / ELLER REGLERING AV EN STROEM AV LUFT OCH ANDRA GASFORMIGA MEDIER - Google Patents

Description

γ-Ί ANNOUNCEMENT ^ ^ 0Γα [Β] (11) utlAggni NCSSKRIFT 60069 c (45) t: '' '11 1:31 ^ ^ (51) tCv.ik-Wci.3 p 24 P 11/04, G 05 D 7/00 FINLAND — FINLAND (21) PtMnttihakamui - Pit * nttn * eknlng 791761 (22) H »k * mlipllvi - Antekninpd ·! 01.06.79 * * (23) Alkuplivi - Giltlghttsdag 01.06.79 (41) Has become slipped - Bllvlt offamllg 02.12.80

Patent · and Registration Board .... w ,. ...., ,,, ». . . . . , (44) Date of issue:. - οι 07 St

Patentl · och registerstyrelsen '' Ansökan utlagd och utLakriftwi publlcarad -5 '· 01 (32) (33) (31) Pyydetty atuoikaut —Bagird prloritat (71) (72) Erkki Johannes Niskanen, Länsituulentie 8 A l6, 02100 Espoo 10, Finland -Finland (FI) (74) Ins.tsto Olli Heikinheimo Ky (5 ^) Method and apparatus for conditioning and / or regulating the flow of air and other gaseous media - Förfarande ooh anordning för konstanthällning och / eller regiering av en Ström av luft och andra gasformiga medier

The invention relates to a method for stabilizing and / or regulating the flow of air and other gaseous media, in which method the throttling of the flow opening is adjusted by taking advantage of the pressure difference arising from the medium's own flow.

The invention also relates to a device for controlling the flow of air and other gaseous media, comprising a cover with a flow opening and a main valve plate, the position of which is adjustable relative to each other, and control devices consisting of a cylinder-piston combination with a piston movement connected to the main valve plate.

The method according to the invention is not linked to any particular system or application. However, the invention is best seen in the application as an adjustable constant flow valve for replacing fixed exhaust air valves in common duct based mechanical exhaust air systems.

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By means of the method and device according to the invention, it is possible in said systems, taking advantage of the pressure difference between the ventilation duct and the room, to adjust the room-specific air flow and keep it constant without changing, within certain limits, the ventilation volumes of other rooms connected to the same system.

It is well known that mechanical exhaust ventilation based on a common duct system has become the cheapest for general use in apartment buildings in terms of construction costs. Such a system is characterized in that the ductwork and the vacuum cleaner are dimensioned to transfer constant air volumes according to ventilation standards from different rooms with the following consequences:

The ventilation valves are set to a fixed position and the adjustment must not be changed on a room-by-room basis, as this will cause the system to become out of balance, changes in ventilation in other apartments connected to the same system and low pressures and flow rates.

The rigidity of the system means that the areas with the greatest ventilation, usually the kitchen and the bathroom, have the greatest need for ventilation throughout the apartment. The result is a high energy loss during the cold season when heating unnecessary ventilation when these spaces are not in use, tonnage, unnecessary energy consumption to maintain sufficient humidity especially in frost, freezing of windows and health disadvantages that become costly to the economy.

Sealing windows and doors on the one hand and closing and opening them on the other hand affect the balance of the system, also causing ventilation mixing between the apartments.

The system is exposed to pressure fluctuations caused by self-traction and wind. This is especially the case when ventilation is reduced collectively by lowering the speed of the vacuum cleaner, e.g. when the temperature is below -15 ° C outside 3,60069 and the pressure difference drops below 10 mm vp.

As can be seen from the above, the possibility of apartment-specific adjustment would be very important for energy savings, public health and comfort and would be of great economic importance. It is a basic precondition for the full application of apartment-specific heat billing with a view to energy savings.

It is already known e.g. devices in which the energy required by the body used to stabilize the volume flow is obtained from the kinetic energy of the medium. Disadvantages include the relatively large pressure difference required, the difficulty of adjustability, and the effects of dust, particularly on the bearings and controls, impairing operation and accuracy.

Also known are devices in which the stabilization of the volume flow is based on the adjustment of the throttle so as to change the shape of the closing member made of a flexible material by means of a pressure difference. The disadvantages are the same as above and, in addition, the fact that the equipment does not meet the fire safety requirements.

In addition, devices that use external energy and devices to stabilize the volume flow are already known. Due to their high cost, these are only suitable for controlling higher airflows.

An apparatus for controlling the flow of gas is known, for example, from U.S. Pat. No. 4,121,762. The apparatus comprises a flow chamber, in the outlet channel of which is placed an axis provided with flow restrictor means, which can be moved in its longitudinal direction by means of a bellows device. The automation of the flow control is based on the fact that there is a pressure difference between the different sides of the flow control valve plate, which manifests itself as a force applied to the plate. The valve plate is kept in balance by a spring which counteracts the force caused by the above-mentioned pressure. Correspondingly, the change in pressure causes the valve plate to move in the axial direction, and thus the flow is also adjusted in a manner corresponding to the change in pressure.

In order for the apparatus described above to function as desired, it requires that the spring constant of the balancing spring of the valve plate be nonlinear. In practice, however, it is impossible to use such springs 4,60069, so that several springs with different spring constants have also been reported in said publication. The bellows can be used to select the desired volume flow.

A device for automatically regulating the flow of a gaseous medium is already known from Finnish patent publication No. 30,755. Ko. the control device comprises a flow opening and a limiting member limiting it, the direction of movement of which is approximately transverse to the direction of flow. The restrictor member is shaped so that the flow causes a pressure difference on different sides of the edge of the restrictor member. The force caused by the pressure difference is parallel to the tendency to close the flow opening. The apparatus also includes a spring which acts against the force generated by the flow and thus tends to keep the flow opening open. By adjusting the spring force, the volume flow through the opening can be regulated within certain limits. The equipment also includes means for damping oscillations.

Furthermore, Finnish Patent Publication No. 30,542 discloses a device for controlling the volume flow of a medium. The device comprises a flow channel and a throttling piece fitted to it. The resistance caused by the flow tends to move the body in a channel formed to curve upwards and at the same time taper. Thus, the throttle body is affected by a force equal to its weight which tends to return the body to its initial position. Because the flow channel is formed to taper, the increase in pressure and the upward movement of the throttle body in the channel cause the flow to be restricted.

The devices disclosed in the above-mentioned patent publications can be considered to have the following disadvantages in addition to those already disclosed. The devices have a number of closely moving and even abrasive surfaces which cause entrapment if the flowing medium, e.g. supply air, or the medium surrounding the device, e.g. exhaust air, contain greasy kitchen or industrial dust. Even a small number has a strong effect on the operation and accuracy of the equipment. The duct noise attenuation properties of the devices are non-existent. In addition, the equipment is not suitable for wall mounting in residential apartments. The device disclosed in Finnish Patent Publication No. 5,60069 still lacks damping means.

The medium flow controller disclosed in said U.S. patent has the disadvantages described above, with the possible exception of duct noise attenuation, in which case the device itself causes a lot of noise. Indeed, in order to operate under the conditions shown, the device requires efficient filtration of the main flow and a remarkably large pressure difference.

The object of the invention is e.g. avoidance of the above disadvantages. This is achieved by the features of the invention as set out in claims 1 and 2.

The main technical advantages of the invention are the following:

The entire control system and all bearing surfaces are in a filtered pilot air mode, so operation is not affected by mainstream contaminants. Thanks to the vacuum field created in the throttling area, the device is made small. The system operates accurately over a wide pressure range from low pressures. It can be built to follow the desired pressure / volume flow function.

The device is suitable for wall mounting and also functions as a fire shut-off valve with a heat trigger, in which case separate fire shut-off valves are not required. The operating range of the device is adjustable. The device has a specific damping, it opens completely when the fan stops and closes when the flow is reversed.

The main advantages of the invention in the embodiment shown are the following. Because the volume flow can be kept constant with a certain accuracy, regardless of the variation of pressure differences, ventilation can be regulated on an apartment-by-apartment basis according to local and temporal ventilation needs and health requirements without changing or disturbing the ventilation of other apartments connected to the same system. This enables significant energy savings and improves the health conditions of housing.

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The valve stabilizes the balance of the common duct system so that the effect of variations in absolute draft due to temperature and altitude differences and variations in pressure due to changes in wind direction is reduced or eliminated. This also improves the chances of taking advantage of the central control.

The design of the entire system is simplified and ensured when the valves eliminate the effect of errors and piping leaks in the pressure drop calculations.

Standardization of ventilation improves the control of the heating system.

The apartment can be ventilated without disturbing the ventilation of other apartments.

The possibility of apartment-specific ventilation control is a prerequisite for making full use of apartment-specific heat billing in an energy-saving way.

Equipped with a fire shut-off mechanism, the valve eliminates the need, under certain conditions, for separate fire shut-off valves with service hatches, securing systems and facilitating maintenance. The desired number of ventilation valves can be installed in the same space.

The pneumatic control itself forms a damping, which prevents the valve from vibrating.

Thanks to its structure and mode of operation, the valve is easy to equip with remote and time control of operation based on different methods.

In the following, the invention will be explained in detail with the aid of the accompanying drawing.

Figure 1 shows a preferred embodiment of the invention in a sectional view

Fig. 2 shows an accessory to the device of Fig. 1. Fig. 3 schematically shows the control principle of the apparatus according to the invention.

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A mounting ring 2 with a base ring 35 is attached to the ventilation duct 1 by means of a mounting compound and nails or screws 17, to which a valve body 3 is attached by means of a sealing compound and screws 34. A bearing housing 16 is attached to the latter by means of three supports. 19. The bearing sleeve 15 and the balls 14 of the ball frame 13 form a symbolically described linear bearing on which the valve stem 11 slides at its front end with a main valve plate 20 and at its rear end with a control valve plate 10. The rear end of the bearing housing is closed by a The latter is corresponding to the above-mentioned bearing sleeve 15, the front end of which is closed by an adjusting plate 27 and a locking washer 26.

The front of the main valve plate forms a housing with a cascade control inlet d ^ drilled in the rear plate. The housing is equipped with a felt filter 25 for cleaning the control air. If necessary, the filter can be enlarged to cover the entire cylinder space by turning the valve base to the opposite position and making the main valve plate of two parts, the front of which must be removed to replace the filter. The main valve plate is attached to the valve stem by riveting via a housing washer 21. At the same time, the latter forms a housing for the Teflon ring 22 and the sliding ring 23, to which the counter spring 24 corresponds at one end.

The valve cover 30 is provided with threaded grooves which, when the cover is rotated, move it axially in the direction of the mandrel, determining its position, which in turn affects the spring force and its volume flow. The guides are pins 32 embedded in a plastic ring 33. The latter at the same time covers the bases of the screws 34 and the structure allows easy removal of the cover for cleaning the valve.

The valve cover 30 is sealed with a mineral felt seal 18 and forms the housing of the central part to which the counter spring 24 corresponds at its front end. The cover is equipped with metal wool extruded sound insulation 31.

The bearing housing with seat rings, the valve base and the main valve plate form a closed space hermetically sealed by a thin rubber or plastic film 6. The latter is fastened 8 60069 by means of plastic O-rings 5 and 7 which at the same time acts as a flow body. The edge of the valve base 19 is bent to protect the membrane and to prevent non-metallic debris burning in the event of a fire from entering the ductwork.

Figure 2 shows an automatic fire shut-off mechanism that can be installed in place of the seat ring 9. The device has a pusher 41 arranged in the housing 39, tuned by a spring 40 and a holder 37, which closes the entire valve in a metal-tight manner, regardless of its adjustment position, by pushing the control valve plate 10 and stem 11 forward when the thermal fuse 36 breaks at about + 70 ° C. The system eliminates the need for separate fire shut-off valves where the duct between the valve and the fire compartment interface is adequately insulated.

Valve operation:

The operation of a private valve is based on the so-called cascade phenomenon known in Pneumatics (e.g. Kurt W Geisler: Regelung von Heiz- und Klima-Anlagen, 2nd ed., Marhold-Verlag, Berlin 1969, p. 65), according to which, with reasonable pressure differences and in the arrangement of Figure 3, if the ratio (p2 - PjJ / Cpj ~ P3) = n is denoted, n = -—-—.

(d ^ dj) 4 + 1

The device has an aperture d ^ drilling the main valve disc 20 of the housing rear panel and drilling d2 corresponds to the control of the valve disc 10 and a seat 9 delimited by the equivalent aperture 0β ^ ν · Thus, e.g. if d ^ = is the pressure differential between the interior of the cylinder and the room space = 1/2 x the total pressure differential .

The valve base 19, the main valve plate 20 and the diaphragm 6 form a cylindrical space located in the duct on the vacuum side. This space is affected through the front by the normal room pressure, which tends to push the valve closed when the cylinder cross-section and piston force are large enough to overcome the total airflow resistance, static pressure on the cross-section of the main valve plate outside the opening, diaphragm resistance, bearing friction and In addition to the piston force of 9,60069, a parallel force is exerted on the main valve plate, which arises from an annular vacuum field on its front surface and which is greatly influenced by the geometric shape of the space after the discharge opening.

By measuring the forces applied to the main valve plate at each cover position and pressure difference, the corresponding ^ eq opening can be dimensioned using the selected d-^ opening and the above formula so that there is a balance between the cylinder and counter forces. In this case, if the valve operates fixed, i.e. only one cover position is used and e.g. as the pressure difference increases and the main valve plate pushes forward, De ^ v increases, weakening the piston force so that as the flow opening decreases enough to keep the flow constant, the piston force and vacuum to stop the movement to a new equilibrium position. Correspondingly, as the pressure difference decreases, the main valve plate moves to the left until the reduced D has increased the reduced piston force enough to stop the movement to a new equilibrium position where the volume flow is unchanged as the orifice increases to match the reduced pressure difference. As a function of the movement of the control valve cone and at the same time the graph of the opening Dg ^ y, a curve is thus formed which is always mechanically determinable and maintains a constant volume flow regardless of pressure fluctuations.

When the valve has to be adjusted, an additional condition arises that the curves obtained with the position of the control valve corresponding to each position of the cover 30 must form a common envelope with sufficient accuracy, which is obtained by superimposing them in the direction of the horizontal axis. In this case, there is always a position of the control valve that meets the balance requirements for both control and pressure fluctuations, and the valve can be used both fixed and adjustable.

In order to form an envelope with sufficient control accuracy, the sum curve of the above-mentioned counter forces must have a certain shape as a function of the movement. This is obtained by a suitable valve characteristic grid (magnitude of volume flow and corresponding total resistance as a function of motion), spring constant (steepness and position of the sum of the counterforce curves as a function of motion), (abrasion and shape resistance as a function of motion).

The structure of the valve can be changed in many ways to suit the operating conditions. Thus, for example, at low pressures, air can be removed in the desired direction perpendicular to the inlet direction, whereby the counterforce forces are considerably reduced. In this case, the control air is led to the exhaust duct via a separate duct. In addition, if necessary, the adjustment of the steering can also be performed by moving the seat ring 9 by changing its sealing method and the locking method of the bearing sleeve 15. In this case, e.g. in the internal installation of the pipe, the cover can also be fixed and the main valve plate can move alone, performing both the basic adjustment of the volume flow of air or other gaseous medium and its correction when the pressure varies. The adjustment of the control can also be performed by adjusting the d ^ aperture either simultaneously with the aperture or separately. Since the shape of the cylinder-blade space is not important for adjustment, the d ^ opening can also be placed in its projection, if necessary. At higher pressures and higher temperatures, the membrane may be replaced with a metal bellows.

Claims (5)

11 60069 A method for stabilizing and / or controlling the flow of air and other gaseous media, in which the constriction of the flow orifice is adjusted by taking advantage of the pressure difference of the medium itself, characterized in that - the flow channel is preferably provided with a cylindrical space with openings (Dg ^ y »dj, which - consists of a fixed base (19) and a piston resiliently connected to it, e.g. acting as a main valve plate (20) - communicates via a first opening (Dg ^ y) to the lower pressure side (p ^) and through a second opening (d ^) to a higher on the side of the pressure (p ^) - the adjustment of the pressure (P2) of the cylindrical space is achieved by changing the mutual surface area ratio of the openings (0β ^ ν> d ^) e.g. by adjusting the main valve plate (20) itself and / or from the outside so that the flow opening the throttling force required to regulate the flow at each moment and the pressure difference is equal to that v the sum of the flow and other forces acting. A device for stabilizing and / or regulating the flow of air and other gaseous media, the device comprising a cover (30) with a flow opening and a main valve plate (20), the position of which is adjustable relative to each other, and control devices consisting of a cylinder-piston combination with a piston the movement is connected to the main valve plate (20), characterized in that the cylinder space (43) is connected by an opening (d ^) to the higher pressure side (p- ^) and by a second opening (Deq) to the lower pressure side (P3) and the ratio of the areas of said openings must be adjusted. Device according to claim 2, characterized in that one of said openings of the control device is formed as a seat ring (9), in the middle of which a control valve plate (10) with e.g. a conical surface is arranged. 60069 12 Device according to Claim 2 or 3, characterized in that the cylinder space is formed by a fixed base (19) located on the lower pressure side and a main valve plate (20) which are hermetically connected to one another by a resilient member (6). Device according to Claim 3 or 4, characterized in that the main valve plate (20) is connected by a stem (11) to the control valve plate (10). 13 60069