IL120473A - Air conditioning device - Google Patents

Abstract

An air-conditioning device which is provided with an evaporator (12) and a liquefier (14) which are located one behind the other in the forward driving direction, in particular on the roofs of large vehicles, such as buses, characterized in that the evaporator is divided thus forming a slit (24) extending substantially in the forward driving direction, the side walls of said slit being provided with suction openings for fresh ai

Description

IN :m>)_)> un AN AIR CONDITIONING DEVICE AURORA Konrad G.Schulz GmbH & Co.

The present invention relates to an air-conditioning device which is provided with an evaporator and a liquefier which are located one behind the other in the forward driving direction, in particular on the roofs of large vehicles, such as buses.

Such air-conditioning devices are known as so-called "on roof air-conditioning devices", in particular on buses. Said devices have, inter alia, the advantage that they enable complete pre-assembling and thus also enable simplified production of the vehicle.

Such an air-conditioning device is known, for example, from DE-OS 32 24 895. Said device is provided with a liquefier block which extends across the entire width of the hood. In order to follow substantially the roof curvature of the bus, the hood is curved at its ends. However, as becomes apparent from Fig. 5, a slit is obtained between the climate hood and the roof of the bus. Said slit requires not only suitably formed connecting fitting parts, but it is also not favorable from the flow-technical aspect, as it increases the air resistance and the construction height of the hood.

A similar construction is also known from De-OS 27 57 415. In accordance with said specification, the climate hood is supported by side carrier rails so that also in this case remains a rather substantial slit.

The most advantageous solution from the flow-technical aspect consists in the possibility that the air-conditioning device is constructed in such a manner that it extends along the entire width of the roof and has a minimum construction height in that it is adapted to the form of the roof. Such a solution has already been 2 120473/2 suggested. However said solution requires significant costs for the adaptation of the model and for the adaptation of the air-conditioning device to different types of buses. Practically the entire construction has in each case to be newly designed, which results in large tool costs.

Modern heat exchangers operate very efficiently in the evaporator. However, in order to achieve a good efficiency degree in the liquefier region large flow cross-sections have to be provided and flat liquefiers have to be used. For reasons of space availability it is therefore advantageous to locate a liquefier in the forward driving direction behind or in front of the evaporator, as is already known, for example, from DE-OS 32 42 895. However, this known air-conditioning device is already quite large and therefore not easy to handle. However, it is desirable even to enlarge the flow cross-section region being available for the liquefier block so that an even larger device will be obtained.

U.S. Patent Specifications Nos. 4,732,011, 4,787,210 and 4,926,655 describe and claim air-conditioning units which may be mounted on several parts of a vehicle. Each of the above patents describes devices in which the evaporator unit is formed as an undivided housing which comprises two divided evaporator-heat exchangers. This requires a fixed width of the air-conditioner and thus fixed positions for the outlets of the cooled air in relation to the width of the vehicle. In view of the fact that the roofs of the vehicles, in particular of busses, have various forms and the position of the air channels which conduct the air in the inside of the vehicle from the air-conditioner is dependent on the type of the vehicle this constitutes a drawback.

The present invention describes and claims an air-conditioning unit for a vehicle that has the big advantage that the evaporator thereof is divided into two parts which are located in different housings. Moreover, the present invention has the advantage that an 2A 120473/2 optimal construction is achieved which corresponds to the form of the roof of the vehicle and the position of the inner air channels, by an adequate positioning of the evaporator parts of the device right or left of the axis of the vehicle. The form of the device is independent from the type of the vehicle.

The object of the present invention, therefore, is to design an air-conditioning device as indicated above, which overcomes the drawbacks of the known units and has an improved efficiency degree in spite of the reduction of the assembly costs, as well as of the storage - and tool costs.

The present invention thus consists in an air-conditioning device as indicated above, characterized in that the evaporator is divided thus forming a slit extending substantially in the forward driving direction, the slide walls of said slit being provided with suction openings for fresh air.

The liquefier is preferably located behind the evaporator in the forward driving direction.

Each evaporator half is advantageously pre-fabricated with consistent outer dimensions; the width of the slit being variable in order to adapt it to the various widths of the roofs of various vehicles. Moreover, suitably, the liquefier is also divided, as is the evaporator, thus forming a slit, certain surfaces of which slit joining in a concise manner the slit of the evaporator.

The suction opening preferably extends along the entire length of the evaporator and is suitably located in the lower area of the slit. Moreover, the suction opening extends preferably at the side walls of the evaporator half along one-third of the height of said side walls. Additionally said suction opening is suitably formed in a nozzle form by curved ends of the side walls pointing towards the slit.

Suitably, each evaporator half consists of at least one upper cup, and in particular of one lower cup, between which cups extends a fresh air/circulating air-flap, an evaporator and a blower; in particular a multiple arrangement of double radial blowers.

The circulating air flap is preferably swingably located at an elevated spot of the lower cup; the swinging axis extending in parallel to the front driving direction; the relation between fresh air and circulating air being steeples adaptable from 0 - 100%, by said swinging axis over a swinging angle of 50-180°, in particular of 70-130° and advantageously of about 120°.

The location position of the circulating air flap is preferably arranged at a height which substantially corresponds to the upper end of the suction opening.

The liquefier and the evaporator are preferably located immediately one behind the other and have substantially the same cross-section. However, said parts may be distanced from each other and in this case the distance between said parts is advantageously bridged by a plate or by a covering.

The liquefier, and in particular the evaporator, are suitably provided on their upper side, with a diagonal surface which extends at an angle of about 25° towards the horizontal level; under which level the liquefier or the diagonally extending radial blower are preferably located.

The fresh air/circulating air flap is preferably formed as a roller section form-like covering element with which element either the fresh air suction opening or the circulating air opening is at least partially coverable in such a manner that the sum of the free flow cross-sections remains substantially equal.

The suction openings are advantageously provided with a device increasing the dynamic pressure and extend substantially in a diagonal manner towards the forward driving direction; or are provided with air conducting elements to provide an over-pressure.

Advantageously at least the evaporator, and in particular also the liquefier, extend substantially vertically at the tail of the vehicle.

As a result of the division of the evaporator, e.g. into two halves or into an asymmetric division, many advantages may be achieved. The evaporator halves and also the liquefier halves may, in an advantageous embodiment, be completely pre-assembled. Thus, all four parts of an air-conditioning unit may be stapled one on top of the other and thus may be transported in a compact manner to the destination i.e. the bus assembly plant. In a very advantageous embodiment each of the individual parts has the same basic surface and the curvature of their upper sides substantially corresponds to the curvature of the lower sides. The tool and storage costs are thus drastically reduced since no different air-conditioning device is required for each different bus type having different lengths and widths of the roof, and no separate tools have to be prepared as reserve parts. Moreover, the fact that most of the bus roofs have a flat surface and are only curved at the sides may be utilized advantageously in connection with the present invention.

The adaptation of the width can be performed by an appropriate assembly at a suitable place on the roof. The fact that the width of the slit is not a critical feature may be suitably utilized and thus the width may be adapted in wide regions to the requirements. Thus, for example, buses having roof widths of 1.80 to 2.80 m may be equipped with the same evaporator halves. It is well understood that the minimum construction width is conditioned by a sufficiently flow technical dimensioned slit. Such slit should have, for example, a minimum width of 5-10 cm.

The fact that the slit extends in the forward driving direction does not cause any losses of flow. On the contrary there are obtained, in the course of the fresh air operation, very suitable in-flow rates with comparatively low flow speeds for the heat exchanger of the evaporator.

The degree of efficiency in the liquefier may become nearer to the theoretical optimum in that there may be used very large, flat lying and comparatively thin liquefiers. Said liquefiers extend advantageously at diagonal outer surfaces of the liquefier halves. The axial blowers which are intended to be used for the through flow of the liquefier are supported in their suction effect by the low-pressure being present centrally to an strengthened extent at the rear end of the bus. In this case only relatively little flow speeds are required due to the largely dimensioned liquefiers.

The provision of the side walls of the slit with suction openings enables, in particular when a relatively narrow slit is used, a good protection of the evaporator against the influences of the weather conditions. As the slit may also be relatively broad the fresh air/circulating air flap may be advantageously located so high, that by displacement towards the fresh air opening a spray water protection is obtained.

In accordance with another advantageous embodiment, the liquefier is located in the forward direction behind the evaporator. The waste heat of the liquefier does then not influence the fresh air supply of the evaporator in the course of the fresh air operation. The axial blowers of the liquefier comprise advantageously engines located in capsules so that the liquefier may be formed in a rain open manner.

The liquefier and the evaporator are formed at their undersides either flat or curved. When the construction is flat it is possible to operate also with a constant slit, so that the adaptation may also be achieved favorably with a flat underside in that the evaporator half is moved outwards to such an extent that blowing into air channels, which are provided outside below the roof of the bus, may be performed without any air diversion.

In accordance with a further advantageous embodiment, it may be considered to provide, in addition to the heat exchangers in the evaporator which serves for cooling, behind same in the forward flow direction further heat exchangers, which additional heat exchangers are heated by the engine heat. In this embodiment also a so-called reheat operation is possible, in which the fresh air in the evaporator-heat exchanger is at first cooled and then humidity is removed; and thereafter the fresh air is again heated in the heat exchanger. It is readily understood that in this embodiment a heating operation may also be obtained by closing the pumps and the axial blowers.

Further details, advantages and features become apparent from the following description of an embodiment of the device according to the present invention with reference to the drawings.

The present invention will thus now be illustrated with reference to the accompanying drawings, without being restricted by same.

In said drawings: Fig. 1 shows a schematic top view of an embodiment of an air conditioning device according to the present invention; Fig. 2 shows a side view of the air conditioning device shown in Fig. 1; Fig. 3 shows a schematic cross-section through a liquefier as part of the embodiment according to Fig. 1; Fig. 4 shows a view from the top on the liquefier according to Fig. 3; Fig. 5 shows a view of the evaporator in the embodiment according to Fig. 1; Fig. 6 shows a cross-section through the evaporator according to Fig. 5; Fig. 7 shows an enlarge clip of the view shown in Fig. 6 for the illustration of a fresh air/circulating air flap; and Fig. 8 shows an alternative embodiment of the embodiment shown in Fig. 7.

The air conditioning device shown in Fig.l comprises evaporator 12 and liquefier 14 which are located one behind the other in the forward driving direction. Evaporator 12 is located in front of liquefier 14. Evaporator 12 consists of two evaporator halves 16 and 18, and liquefier 14 consists of two liquefier halves 20 and 22.

Evaporator half 16 is distanced from evaporator half 18 by slit 24. Said parts are mounted on a roof (not shown) of a vehicle (not shown) , i.e. of a bus. Said bus may be replaced by any other 8 large vehicle which requires air conditioning. In the embodiment shown in Fig. 1, evaporator 12, as well as liquefier 14, each extend tightly along the entire width of the vehicle. The distance between evaporator halves 16 and 18 and therefore the width of slit 24, are so dimensioned that the blowers shown in Fig. 6 may blow with their outlet openings directly into the pressure channels located at the side on the top of the roof of the vehicle.

Slit 24 extends in the illustrated embodiment along the entire length of air conditioning device 10 and thus divides halves 20 and 22 of liquefier 14 as well as halves 16 and 18 of evaporator 12. The air flow obtained by the driving wind can therefore enter into slit 24 without any disturbances.

Evaporator 12 is distanced from liquefier 14 via a further slit 26. In the embodiment shown in Figs, l and 2 said slit is provided in order to obtain a good heat insulation between the evaporator and the liquefier. If not required, slit 26 has not to be present and then parts 12 and 14 are formed in such a manner that they are connected tightly one to another. When slit 26 is present, it is advantageous to provide cover 28 which extends in the form of an U-like band over slit 26 between halves 16 or 20 or halves 18 and 22, respectively and serves to avoid the whirl losses which otherwise may be created.

Liquefier 14 comprises two liquefiers 30 and 32 which extend in an angle of about 25° in halves 20 and 22 respectively, and cover nearly half of the basis surface of the corresponding half.

As becomes apparent from Fig. 2 evaporator 12 at the front and liquefier 14 behind are provided with a diagonal surfaces 34 and 3 -376", respectively. Said diagonal surfaces 34 and 36 improve the ιη- and out-flow and may be formed in any suitable manner.

Fig. 3 illustrates the position and arrangement of liquefiers 9 30 and 32. Each liquefier half 20 and 22 has an upper cup which serves simultaneously as housing and as assembling location for liguefiers 30 and 32 and for corresponding axial blowers 40.

In accordance with another embodiment, there is provided a part of a synthetic material which is used as lower tub and serves as carrier for the axial blowers and as upper part of the liquefier.

The axial blowers blow freely upwards and operate therefore in the suction device so that fresh air is drawn through liquefiers 30 or 32 and blown out by axial blower 40.

As becomes apparent from Fig. 4, in the exemplified embodiment are located two axial blowers one behind the other for each half 20 and 22. The number of the axial blowers may be reduced or increased. According to the present invention it is particularly favorable that the entire operation flow for the axial blower 40 is lower than in the prior art as comparatively large, flat, equally admitted and longitudinally extending liquefiers 30 or 32 are used. Space 42 serves practically as low-pressure space and causes equal continuous flow through liquefier 30 or 32. Said embodiment has the advantage that it is relatively independent from the driving wind so that also when the bus stands, the efficiency degree does not decrease to such an extent that the safety reserve for the operation of the air-conditioning device which is usually required may not be reduced.

Fig. 5 shows that the air conditioning device in the illustrated advantageous embodiment comprises four double radial blowers which are located in evaporator halves 16 or 18. In comparison with the axial blowers, the double radial blowers provide a significantly higher pressure. Air is also conducted, in the course of the suction operation, through evaporator-heat exchangers 46 and 10 48. Each evaporator half consists of one upper cup 50 and one lower cup 52, which are notched and/or screwed together for the pre-assembling. Lower cup 52 forms condensation water basin 54 for the reception of evaporator-heat exchanger 46 or 48. Said water basin 54 has a sufficient width that so when reguired an additional heater-heat exchanger 56 or 58, as shown schematically in Fig. 6, may be located therein. When no reheat operation is desired, said heater-heat exchanger 56 or 58 are not reguired.

Evaporator halves 16 and 18 may be operated both with fresh air as well as with circulating air. For this purpose fresh air/circulating air flaps 60 and 62 are provided which flaps are located with their swinging axis 64 and 66, respectively on lower cup 52. With fresh air/circulating air flap 60 or 62 there may be operated a circulating operation in which flap 60 or 62 extend vertically ; as well as a fresh air operation in which the circulating flap extends substantially in a horizontal manner. However, also a mixed air operation may be achieved, as is illustrated by the position of fresh air/circulating air flap 60 in Fig. 7.

Slit 24 is limited at the bottom by roof 70 of the bus and at the sides by side walls 72 and 74 of evaporator halves 16 and 18. Side walls 72 and 74 each have a suction opening. In Fig. 7 suction opening 76 can be seen clearly.

As becomes apparent from Fig. 7, fresh air filter 78 is located between suction opening 76 and fresh air/circulating flap 60. When operating with 100% circulating air fresh air/circulating air flap 60 extends parallel to fresh air filter 78 and thus seals therewith suction opening 76. In a preferred embodiment, suction opening 76 is displaced higher in relation to fresh air filter 78 which causes an increases of the spray water protection. Moreover, 11 it is formed in the form of a nozzle by the ends of side wall 72 curved towards slit 24. Said embodiment achieves particularly advantageous in-flow ratios with certain flow soothing and equalizing zones located between suction opening 76 and fresh air filter 78.

In the embodiment shown in Fig. 6, the evaporator is provided with a plane lower area. It is readily understood that said embodiment is chosen when the evaporator halves 16 and 18 are not to be closed at the side by the side walls of the buses, but a more central arrangement is chosen.

In the embodiment closing the side walls, the outer side end of lower cup 52 is curved to a certain extent downwards and thus follows the roof curvature.

It is readily understood} that a corresponding arrangement may also be provided for .evapora or halves 20 and 22.

As becomes apparent from Fig. 6, a pressure support of blower 40 is formed in a curved manner and extends as part of lower cup 52. Upper cup 50 extends in this region as diagonal surface 82 corresponding to the diagonal surface above liquefiers 30 and 32. In another embodiment, the lower cup terminates at the upper outer end of the flange of double radial blower 44 and upper cup 50 extends curved downwards. Said embodiment is being chosen when the curvature of the outer region of the evaporator halves should be adapted to the outer region of the roof curvature.

It is readily understood that evaporator halves 16 and 18 may be optionally pushed from each other in order to enable an adaptation to the various widths of the roof. The same applies to liquefier halves 20 and 22 which advantageously are in alignment with evaporator halves 16 and 18.

Another embodiment of the fresh air/circulating air flap is 12 illustrated in Fig. 8. In said embodiment roller section formed cover element 84 is provided for circulating air opening 86 and fresh air-suction opening 76. Said element is swingable around swinging axis 88 which is distanced from the openings and enables to leave the openings entirely free and to cover same, but also enables a mixed operation. In view of the fact that circulating air opening 86 and fresh air opening 76 have the same width -calculated vertically to the drawing level in accordance with Fig. 8 - an equal flow cross-section is left free in the course of the swinging of the cover element. Thus, the sum of the free flow cross-sections remains equal, which ascertains equal pressure ratios also in the mixed operation.

It is readily understood that instead of the preferred embodiment in which the liquefier and the evaporator have the same cross-section, also an embodiment with different cross-sections is possible. This possibility is within the scope of the present invention. However, it is advantageous to realize an adaptation of various effects of evaporator and liquefier by a different construction length. The liquefier and the evaporator may also be mounted with an adequate separation even of several meters when this is more favorable for reasons of space. It is also possible to construct liquefier and evaporator 14 and 12 only with lower parts and to produce them with a common cover which may be made of, e.g. a synthetic material. In another embodiment only a narrow slit of a few centimeters is left between liquefier and evaporator 14 and 12 and in this case the slit may be left open without any cover .

In another embodiment, no diagonal surface 82 is provided so that both the liquefier and the evaporator 14 and 12 extend with their upper sides straightforward up to the side end or up to the 13 optionally provided radius located there. However, also in this embodiment, liquefiers 30 and 32 are advantageously mounted in a diagonal direction.

In a further embodiment it is considered to compensate by flow-technical means the dynamic lower pressure resulting, by high speeds of, e.g. the buses, in the region of the tail end of the buses. Thus, for example, fresh air/suction opening 76 may be arranged diagonally in relation to the forward driving direction so that between both liquefier halves 20 and 22 there is formed a slit which extends convergently to the tail. Said slit creates an over-pressure in the course of accelerating forward driving speed which compensates the low-pressure at the outer sides of the bus.

A different embodiment for the compensation of the dynamic low-pressure consists in the insertion of air conducting sheets which extend across or diagonally in relation to the fresh air-suction opening and cause, due to the head wind, an over-pressure at suction opening 76 in the course of accelerating driving speeds.

A further different embodiment consists in that the modular air-conditioning device according to the present invention is mounted as tail device. Advantageously, evaporator halves 16 and 18 may be assembled, in this embodiment, either vertically or horizontally. In the assembling as tail device a modified construction is advantageously utilized for the liquefier, which is construction is designed for vertically extending components. In the course of the tail assembly the modular parts may be assembled one upon another so that evaporator 12 extends advantageously directly adjoining the tail and on each evaporator half 16 and 18, the corresponding liquefier half 20 and 22, respectively is mounted .

It is readily understood that instead of said construction 14 liquefier 14 may be assembled also above or below evaporator 12 at the tail of the vehicle. Moreover, one can also use an integrated construction method in which the vehicle skin extends over the evaporator and the liquefier.

Claims (1)

An air-conditioning device which is provided with an evaporator and a liquefier which are located one behind the other in the forward driving direction, in particular on the roofs of large vehicles, such as buses, characterized in that the evaporator is divided thus forming a slit extending substantially in the forward driving direction, the side walls of said slit being provided with suction openings for fresh air. An air-conditioning device, according to Claim 1, characterized in that the liquefier is located behind the evaporator in the forward driving direction. An air-conditioning device according to Claim 1 or 2, characterized, in that each evaporator half is pre-fabricated with constant outer dimensions; the width of the slit being variable in order to adapt it to the various widths of the roofs of various vehicles. An air-conditioning device according to any of Claims 1 to 3, characterized in that the liquefier is also divided, as is the evaporator, thus forming a slit, certain surfaces of which slit joining in a concise manner the slit of the evaporator. An air-conditioning device according to any of Claims 1 to 4, characterized in that the suction opening extends along the entire length of the evaporator and is located in the lower area of the slit. An air-conditioning device according to any of Claims 1 to 5, characterized in that the suction opening extends at the side walls of the evaporator half along one-third of the height of said side walls. An air-conditioning device according to any of Claims 1 to 6, characterized in that said suction opening is formed in a 16 nozzle form by curved ends of the side walls pointing towards the slit. An air-conditioning device according to any of Claims 1 to 7, characterized in that each evaporator half consists of at least one upper cup, and in particular of one lower cup, between which cups extends a fresh air/circulating air-flap, an evaporator and a blower; in particular a multiple arrangement of double radial blowers. An air-conditioning device according to any of Claims l to 8, characterized in that the circulating air flap is swingably located at an elevated spot of the lower cup; the swinging axis extending in parallel to the front driving direction; the relation between fresh air and circulating air being steeples adaptable from 0 - 100%, by said swinging axis over a swinging angle of 50-180°, in particular of 70-130° and advantageously of about 120°. An air-conditioning device according to any of Claims 1 to 9, characterized in that the location position of the circulating air flap is arranged at a height which substantially corresponds to the upper end of the suction opening. An air-conditioning device according to any of Claims l to 10, characterized in that the liquefier and the evaporator are located immediately one behind the other and have substantially the same cross-section. An air-conditioning device according to any of Claims l to 11, characterized in that the liquefier and the evaporator are distanced from each other and the distance between same is bridged by a plate or by a covering. An air-conditioning device according to any of Claims 1 to 12, characterized in that the liquefier, and in particular the 17 evaporator, are provided on their upper side, with a diagonal surface which extends at an angle of about 25° towards the horizontal level; under which level the liquefier or the diagonally extending radial blower are located. An air-conditioning device according to any of Claims 1 to 13, characterized in that the fresh air/circulating air flap is formed as a roller section form-like covering element with which element either the fresh air suction opening or the circulating air opening is at least partially coverable in such a manner that the sum of the free flow cross-sections remains substantially equal. An air-conditioning device according to any of Claims 1 to 14, characterized in that the suction openings are provided with a device increasing the dynamic pressure and extend substantially in a diagonal manner towards the forward driving direction; or are provided with air conducting elements to provide an over-pressure. An air-conditioning device according to any of Claims 1 to 15, characterized in that at least the evaporator, and in particular also the liquefier, extend substantially vertically at the tail of the vehicle. An air-conditioning device as defined in

1. Claim 1, substantially as hereinbefore described with reference to the accompanying drawings. For the Applicant: Dr. Yitzhak Hess & Partners