FI92431B - Device for air conditioning units - Google Patents

Description

92431

Device used in air conditioning equipment

The invention relates to a device for use in connection with an air conditioner equipped with a cross-flow type plate heat exchanger-5a, comprising - at least one exchanger element with a plurality of substantially parallel plates forming mutually intersecting, intersecting flow channels 10 for supply air. relatively cold outdoor air, and for outflow air, which is normally relatively warm exhaust air, and a side damper rigidly connected to the derailleur, which in the open position of the 20 damper at least partially closes the bypass passage and the derailleur in the closed position release it.

Such a device is known from the Finnish Announcement 76 420, in which case there are two gear elements. 25 spaced apart to form a common bypass channel therebetween. The derailleur damper belonging to each derailleur element is pivotally mounted around an axis which runs along the edge of the derailleur element in the vicinity of the bypass channel, namely in a plane passing substantially 30 bypass channels. In the closed state, the derailleur damper extends slightly inwards over the inlet of the bypass duct and joins the outwardly directed side damper plate, which forms an acute angle with the derailleur damper plate. In this case, the aim is for the damper plate in question (after turning to the open position) to form a supply air flow deflection control gear element towards the flow channels and the bypass duct, whereby both side damper plates close the inlet duct 5 after turning into the closed position.

However, this known arrangement has certain drawbacks. Since the two sheet metal plates form an acute angle with each other, these sheet metal plates must be turned more than 90 ° between the respective closing end positions. Such a large turning angle combined with the high torque requirements in both end positions (to achieve effective closing) requires the use of powerful, expensive and space-consuming adjusting members. In addition, a lot of free space is required to receive the rotary damper swivel-15 movement of more than 90 °. These disadvantages cannot be eliminated by allowing the sheet metal plates to form an obtuse angle with each other, since then in the open position the sheet metal plate slanted interferes with the air flow, resulting in turbulence, pressure drop and loading of the sheet metal device 20.

Against this background, it is an object of the invention to provide an improved device of the quality indicated in the introduction, in which case the sheet metal device only needs to be turned by a reasonable angle, so that it can be operated reliably with relatively simple and inexpensive setting means. In addition, the aim is to have a simple mechanical structure, favorable flow conditions and the possibility of achieving a rapid resetting of the sheet metal device.

These objects are achieved by the specific features indicated in the characterizing part of claim 1. Thus, the pivot axis of the derailleur is oriented perpendicular to the plane of the derailleur plate and located in the vicinity of one corner edge of the derailleur element. The inlet or outflow bus is connected to the bypass channel and comprises inlet and outflow

II

3 92431 oriented parallel to the plane of the shifter plates. This inlet or outlet opening is closed when the damper is closed by means of a side damper plate fixedly connected to the peripheral part of the damper and connected perpendicular thereto and acting as a thrust damper with respect to the inlet and outlet of the bypass, although closing in its plane.

The device according to the invention is preferably (in a manner known per se, cf. the above-mentioned Finnish publication) mentioned at least with two switching elements arranged on both sides of a common bypass channel (or several such adjacent units). In order to provide a particularly simple and reliable mechanical structure in connection with a structure which would also allow intermittent use for intermittent use of one gear element at a time, the inlet or outlet passage of the bypass channel is preferably limited by a strip-like wall portion with an bypass extension. , on the outflow side), so that each derailleur element has an inlet or outflow opening which cooperates with a derailleur plate connected to the derailleur plate.

Other advantageous features appear from the dependent claims 3-10. The device according to claim 10 can thus advantageously be readjusted between different operating cases by controlling the supply air temperature sensor, in particular the outdoor temperature sensor, namely summer operation (all damper ducts closed and all air flowing through the bypass duct) and so-called winter operation (all the damper open and the bypass damper closed) and the so-called defrost drive, whereby one switch element is closed at a time and the supply air is distributed between the bypass duct 35 belonging to the closed switch element and the other open switch elements.

1 · 4 92431 Thus, the total air flow during defrosting can be kept substantially constant, a certain heat recovery can be maintained and all exchanger elements can be kept free of ice, which can otherwise impair heat recovery or even block the flow channels. The readjustment between the different applications can be carried out quickly and efficiently thanks to the relatively small turning angles of the sheet metal devices and the simple mechanical structure, which ensures reliable operation and a long service life of the device.

The invention will be explained in more detail below with reference to the accompanying drawings, which illustrate a preferred embodiment of the device of the invention.

Figure 1 schematically shows an apparatus according to the invention comprising a plate heat exchanger for recovering heat from the outflow air (normally exhaust air) to the supply air (normally outdoor air); Fig. 2 shows a perspective view (obliquely from the left in Fig. 1) of the plate heat exchanger of the device and the associated damper device with both exchanger dampers 20 closed; Fig. 3 shows the plate heat exchanger of Fig. 2 with both exchanger plates open; Fig. 4 shows the plate heat exchanger of Fig. 2 with one exchanger damper open; and Figure 5 shows a cross-section of the plate heat exchanger of Figure 2.

The air conditioner shown in Fig. 1 consists essentially of a cross-flow type plate heat exchanger 1 for recovering heat from the exhaust air, normally relatively warm exhaust air F, to the supply air, normally relatively cold outdoor air U. The exhaust air F flows through the inlet part 2 through the limited flow channels to the outlet part 4 provided with the exhaust air fan 5 and flows out as exhaust air A.

5,92431

The outdoor air U flows as a filter 7 and an inlet part 6 provided with an outdoor temperature sensor 8, through flow channels in the plate heat exchanger 1, which through the parallel plates 9 (see Fig. 2) ra-5 flow into the exhaust air flow ducts 11 via the air heaters 11 The air heater 11 can be electric or water-operated and operates depending on the temperature of the supply air T, which is known by the sensor 13, so that the supply air T is kept constantly at the desired temperature level, e.g. about +20 ° C.

The plate heat exchanger 1, shown more clearly in Figures 2-5, in this exemplary embodiment consists of two separate exchanger elements 14 and 15 15, the intermediate space forming a bypass duct 16 (see Figure 5) on the sides facing the exhaust air inlet and outlet sections 2, 4. closed by side walls 17, so that the supply air can flow freely through the bypass duct 16 when the inlet passage leading to it is open, of which more later.

Each exchanger element 14, 15 consists of a plurality of mutually parallel plates 9 (as mentioned above) which are substantially square, so that the exchanger elements have the shape of a cube or a parallelogram with a square bottom surface (in the plane of the plates 9), the heat exchangers 14, 15 being arranged so that the diametrically opposed corner edges 18, 19 are fixed by means of relatively narrow, vertical wall portions 20, 21 to the upper and lower walls 30 22 of the box-like housing 24, and so on. 23 (shown only schematically in Fig. 1) in which the device is placed. The two remaining corner edges 25 and 26 each join their horizontal partition walls 27 and resp. 28 in the housing 24.

In order to close the supply or outdoor air flow passages 29 (the corresponding flow passages 30 for the outflow or * · 6 92431 exhaust air F, on the other hand, are always kept open), plate-shaped exchange dampers 31, 32 are dimensioned to cover the part of the exchange element 14, 15 facing the inlet part 6. the entire surface of the side between the corner edges 18 and 25. Each exchange damper 31, 32 is pivotally mounted around a pivot axis 33 perpendicular to the plates 9 in the vicinity of the corner edge 18 closest to the upper wall 22 of the housing 24. Thus, good flow conditions can also be achieved with a limited opening of the respective exchange plates 10 by turning upwards by about 30-45 ° from the closed position (cf. Fig. 1).

For each derailleur plate 31 and resp. 32 is associated with a substantially circular sector shaped sheet metal plate 34 and resp. 35 (see Figs. 3 and 4) connected to the edge portion of the shifter plate 31, 32 closest to the bypass duct 16 and extending perpendicularly therefrom towards the interior of the bypass duct 16 in a plane parallel to the shifter plates 9. Side damper plate 34 and resp. 35 thus extends from the pivot axis 33 of the sheet metal device, next to the corner edge 20 18 to the opposite corner edge 25 and protrudes in its entirety into the bypass channel 16 when the corresponding gear damper 31 or resp. 32 is closed. In connection with the latter opening, the side sheet plate 34 or equivalent is pulled. 35 out like a damper and then closes the inlet openings 36 and 25, respectively. 37 to the inlet passage 38 of the bypass channel 16, which is bounded on the entry side by a strip-like wall portion 39 located on the extension side of the bypass channel 16. The wall portion 39 consists of a first straight strip part 39a, which leaves the exchanger 14, 15 of the joint an angle of 30 masärmäviivasta 18 (17 vicinity of the wall portion) and is directed obliquely outwards to some extent half the kulmasärmäviivojen 18 and 25 a distance past the preferably 20 -30 bp angle to the exchanger inlet surface (the plane between the corner edge lines 18 and 25) and a second straight strip portion 39b associated therewith, preferably at an obtuse angle, 35b, which joins the opposite corner edge line 25 (in the vicinity of the wall portion 17). Both inlet openings 36, 37 are thus delimited by the corresponding edge of the wall part 39 and by the edge 40 and the respective element 15, 14 of the exchanger-5 located closest to this wall part. 41 (see Figure 2).

Exchanger dampers 31, 32 with their associated side damper plates 34 and resp. 35 are controlled separately by each of its electric setting motor 42 and resp. 43, which in the exemplary embodiment shown is fixed to the outside of the respective exchanger-10 sheet metal plate 31, 32 and connected to a fixed, intermediate wall part 39 by an articulation device 44 with two or more articulated arms and the like. Through 45. The exchange dampers 31, 32 can thus be opened and closed independently of each other, whereby the respective side damper plates 34, 35 simultaneously close or open the respective inlet opening 36, 37 into the bypass duct 16. The area of said inlet opening 36, 37 and the cross-sectional area of the bypass duct 16 the area is dimensioned so that the supply air pressure drop remains substantially the same regardless of whether the supply air passes through the derailleur element 14, 15 (with the derailleur open and side flap closed) or through the corresponding inlet duct 36, 37 and bypass duct 16 (with the derailleur closed and side cover open). Thus, the total pressure drop and thus also the inlet air flow through the heat exchanger 1 can be kept substantially constant and independent of the damper control.

The described device is preferably allowed to operate as follows:

In the so-called summer operation, i.e. when the outdoor temperature sensor 8 senses a relatively high temperature, e.g. above + 15 ° C, both diverter dampers 31, 32 are kept closed, as shown in Fig. 2, so that all supply air U passes through the bypass duct 16 through the free inlets 36, 37. At lower temperatures of 35, in so-called winter use, ie when the outdoor temperature • • 8 92431

the state sensor 8 senses a temperature within a predetermined, relatively lower, preferably adjustable temperature range, e.g. between + 15 ° C and -10 ° C, both exchange dampers 31, 32 are kept open, as shown in Figures 5 1 and 3, so that all supply or outdoor air U

passes through the flow channels 29 of the exchange elements 14, 15. This results in a relatively good temperature-to-space efficiency, at least 50%, whereby the air heater 11 covers the remaining heating power demand.

At even lower outdoor temperatures (so-called defrost operation), i.e. when the sensor 8 detects an outdoor temperature below a predetermined, relatively low, preferably adjustable temperature, e.g. -10 ° C, the damper dampers 31, 32 are periodically controlled alternately to open and for a predetermined period of time, the shifter 31 of the second shifter element 15 is kept closed, whereby the warm exhaust air flowing through it melts this shifter element and the outside air is distributed between the second shifter element 14 and 20 bypass duct 16. closed so that this second gear element melts. This results in a lower temperature efficiency, about 25%, whereby the air heater 11 brings in the remaining 25 thermal power.

Resetting between different operating cases is achieved by means of electrical control devices (not shown) connected to the temperature sensors 8 and 13 and to the electric motors 42 and 43.

30 The device described can be modified within the scope of the claims. Optionally, only one switch element with adjacent bypass channels can be arranged as well as three or more switch elements, each with a corresponding bypass channel, which can possibly be common to two adjacent, separated switch elements.

Furthermore, the control of the sheet metal devices can be achieved in another way, for example by fitting the setting motor 5 to one of the wall parts 20, 27 or 38 or by acting on the pivot shaft. The wall part 39, which delimits the inlet passage 38 of the bypass duct 16 with its inlet openings 36, 37, can of course also be shaped in a manner other than that shown.

10 Dampers 31, 34 and resp. Instead of placing the passage 38 of the bypass duct 32, 35 and the bypass duct 16 on the inlet side, these dampers and the corresponding outflow passage with outflow openings can be arranged on the outflow side of the heat exchanger in connection with the outflow part 10.

Finally, it is conceivable to control the corresponding electric motor 42, 43 under certain operating conditions so that the corresponding gear damper 31 or resp. 32 opens at a small opening angle, so that the side sheet plate 34 or 35 in question closes only a part of the inlet 36 or 37 leading to the bypass duct 16 20. Thus, the heat recovery rate in the respective exchange element 15 or equivalent decreases. 14, which may be advantageous when the outside air temperature is somewhat below normal room temperature or moderate winter temperatures, e.g. about -10 ° C, in which case there is a risk of ice forming in the exchange plates.

Claims (10)

Apparatus for air conditioning units with a cross-flow type heat exchanger (1), comprising - at least one gear cell (14, 15) having a plurality of substantially parallel plates (9) forming between them, intersecting, intersecting flow channels (29, 30) for inlet air, which is normally made up of relatively potassium outside air (U), and the outlet air, which is normally made up of relatively hot fresh air (F), - a shunt duct (16) adjacent to the switch cell (14, 15) for flow through inlet air ( U) past the switching cell under certain operating conditions, 15. a pivotally stored switching damper (31, 32), which in open position exposes the through-pass ducts (29) for inlet air (U) and in the closed position shuts the same, and - one with the switching damper (31, 32). ) rigidly connected shunt damper (34 and 35, respectively), which in the open position of the switch damper 20 at least partially shuts off the shunt channel (16) and in the closed position of the switch damper, releases the same, characterized in that - the shutter damper (31, 32) is arranged about an oblique axis (33) oriented perpendicular to said plates (9). 25, the shunt channel (16) connects to an inlet or outlet passage (38) with an inlet and outlet (18). outlet port (36, 37) located in a tab oriented parallel to said plates (9), and 30. that the shutter damper (34, 35) is perpendicular to the gear damper oriented and having an edge portion of this joined damper blade (34, 35), which, during swinging of the switch damper (31, 32), acts as a push damper relative to said inlet and. outlet opening to the shunt channel. li 92431 Device according to claim 1, wherein at least two switching cells (4, 15) are arranged on either side of a common shunt channel (16), characterized in that said inlet or outlet passage (38) of the shunt channel 5 is at least partially delimited by a band-shaped wall portion (39) located in the extension of the shunt channel (16), the edge portions of said band-shaped wall portion constituting boundary edges of two inner and outer channels, respectively. outlet openings (36, 37) of the shunt channel (16) belonging to each of the changing cells (15, 14). Device according to claim 2, characterized in that said band-shaped wall portion (39) extends from a corner edge (18) which is in line with said corner edge (18) of the respective gear cell 15 (14, 15), to an opposite corner edge (25). 4. Apparatus according to claim 3, characterized in that said wall portion (39) comprises two rectilinear strip portions (39a, 39b) which form a trub-big angle with each other. Device according to any of the preceding claims, characterized in that the respective gear damper (31, 32) and the associated damper blade (34, 35) are operable by means of an electric motor (42, 43) which operates a link device (44, 45) between the switch damper 25 (31, 32) and a wall portion (39) attached to the switch cell. Device according to claim 5 in combination with any of claims 2-4, characterized in that an electric motor (43, 42) belonging to a respective gear cell (14, 15) is mounted on the corresponding switch damper (32, 42). associated switching damper (32, 31), the linking device (45, 44) being connected to said band-shaped wall portion (39). 92431 16 Device according to any of the preceding claims, characterized in that the respective shunt damper blades (34, 35) project from an edge portion of the switch damper (31, 32) and extend inwardly towards the lower of the shunt channel (16). 8. Apparatus according to claim 7, characterized in that the shutter damper blade (34, 35) is substantially circular sector-shaped with a circular center located in the region of the pivot shaft line (33). Device according to any of the preceding claims, wherein the plate heat exchanger (1) is mounted in a leather-shaped housing (24) with diametrically opposed corner edges (18, 19) of the respective gear cell (14, 15) fixed at two resistances, in particular upper and lower housing walls (22, 23), characterized in that the pivot shaft (33) for the respective shutter dampers (31, 32) is located in the vicinity of one (22) of said opposing housing walls. Apparatus according to any of the preceding claims, wherein the plate heat exchanger comprises at least two exchanger cells (14, 15) and a temperature sensor (8) is arranged on the inlet side of the exchanger cells (14, 15) for sensing the temperature of the inlet air and setting of the exchanger voltage. (31, 32) and associated shutter dampers (34, 35) by means of electrical and mechanical control means (42, 43), characterized in that said control means are arranged to - upon sensing an inlet air temperature exceeding a predetermined, high operating temperature, preferably adjustable temperature, e.g. +15 ° C, close all switching dampers 30 (31, 32), so that all inlet air passes through said shunt duct (16) or ducts and associated inlet and duct respectively. outlet openings (36, 37), - upon sensing an inlet air temperature lying in a predetermined, relatively lower, preferably adjustable li. Temperature ranges, e.g. between +15 ° C and -10 ° C, open all the exchanger valves (31, 32), say that the entire inlet air flow flows through the exchanger cells (14, 15), while the shunt damper blades (34, 35) close in or out. the outlet openings (36, 37) of said shunt duct (16) or ducts, and - upon sensing an inlet air temperature below a predetermined relative layer, preferably adjustable temperature, e.g. -10 ° C, intermittently and alternately shutting down respective shutter dampers (31, 32) for counteracting or eliminating ice formation on said plates (9), whereby shunt damper blades (34, 35) of respective shutter dampers (34, 35) expose the respective inlet or shutter. outlet port (36, 37) of said shunt channel (16) so that the total inlet air flow is poured substantially constant.