A roof-mounted parking air conditioner

Abstract

The application provides a top-mounted parking air conditioner, which comprises a shell, an air return port, a heat exchanger, a fan and an air return air guide structure, the air return port is arranged on the shell, the heat exchanger is arranged in the interior of the shell, the fan is arranged in the interior of the shell to drive airflow to enter the shell from the air return port and exchange heat with the heat exchanger, and the air return air guide structure is arranged in the interior of the shell and at least partially located between the air return port and the heat exchanger, so that the air inlet of the air return port can be guided to different positions on the heat exchanger through the air return air guide structure. According to the application, the airflow distribution uniformity on the heat exchanger is improved, so that the heat exchange of the heat exchanger is more uniform, the refrigeration / heating performance of the top-mounted parking air conditioner is improved, and the problem of uneven heat exchange of the evaporator is solved.

Description

Technical Field

[0001] This invention relates to the field of refrigeration technology, specifically to a roof-mounted parking air conditioner. Background Technology

[0002] Currently available roof-mounted parking air conditioners have a compact structure. The drainage channel inside the evaporator is directly connected to the outside environment. When the internal fan is turned on, the evaporator will form a negative pressure chamber. Outside air will enter the evaporator through the drainage channel, and after passing through the heat exchanger, the return air will be blown out from the inner air outlet through the evaporator fan. When the air conditioner is cooling, the outlet air temperature will increase, increasing the load inside the vehicle and reducing performance and user experience.

[0003] Because it is installed on the roof, the height of its outdoor unit is limited, which in turn limits the height of the heat exchanger, thus limiting the heat exchanger's frontal area and consequently its performance.

[0004] Because the indoor unit is placed indoors through a skylight, the air outlet and return air outlet are limited by the size of the skylight. The width of the return air outlet is much smaller than the length of the heat exchanger, which results in low air velocity, uneven heat exchange, and poor performance in the part of the heat exchanger far from the return air outlet.

[0005] Because the width of the return air vent in the existing roof-mounted parking air conditioner is much smaller than the length of the heat exchanger, resulting in low air velocity and uneven heat exchange in the part of the heat exchanger far from the return air vent, this invention studies and designs a roof-mounted parking air conditioner. Summary of the Invention

[0006] Therefore, the technical problem to be solved by the present invention is to overcome the defect that the width of the return air vent of the existing roof-mounted parking air conditioner is much smaller than the length of the heat exchanger, resulting in low wind speed and uneven heat exchange in the part of the heat exchanger far from the return air vent, thereby providing a roof-mounted parking air conditioner.

[0007] To address the above problems, the present invention provides a roof-mounted parking air conditioner, comprising:

[0008] The system comprises a housing, a return air inlet, a heat exchanger, a fan, and a return air guide structure. The return air inlet is disposed on the housing, the heat exchanger is disposed inside the housing, and the fan is disposed inside the housing to drive airflow from the return air inlet into the housing and exchange heat with the heat exchanger. The return air guide structure is disposed inside the housing and is at least partially located between the return air inlet and the heat exchanger. The return air guide structure can guide the incoming air from the return air inlet to different positions on the heat exchanger.

[0009] In some embodiments, a central plane perpendicular to the axis is made at a position halfway along the axial direction of the fan, and the distance between different positions on the heat exchanger and the central plane is L. x And:

[0010] X = (L x -(β1*L f ) / 2) / ((β1*L f ) / 2);

[0011] The return air guide structure ensures that the static pressure ratios Y and X of the airflow within the heat exchanger satisfy the following relationship:

[0012] Y = 1 - β²X 2 -β3X;

[0013] in:

[0014] L z The length of the heat exchanger extending in a direction parallel to the fan axis;

[0015] L f The length of the fan extending along its axial direction;

[0016] β1: Effective return air correction factor;

[0017] β2: Auxiliary correction coefficient for static pressure ratio curve;

[0018] β3: Static pressure ratio curve correction factor.

[0019] In some implementations...

[0020] The heat exchanger extends for a length L in a direction parallel to the fan axis. z Greater than the length L of the fan extending along its axial direction f L z >L f And L z ≤3β1L f .

[0021] In some implementations...

[0022] L z The value range is 600-1000mm, L f The value range is 250-400mm, the value range of β1 is 1.1-1.4, the value range of β2 is 0.5-0.75, and the value range of β3 is 0.15-0.3.

[0023] In some implementations...

[0024] There are two or more return air inlets, which are distributed sequentially at intervals along the length of the heat exchanger. There are also two or more return air guiding structures, with at least a portion of the return air guiding structure disposed between two adjacent return air inlets. Furthermore, at least a portion of the return air guiding structure extends from the return air inlet to connect with the heat exchanger or to be spaced at a predetermined distance from the heat exchanger.

[0025] In some implementations...

[0026] Within the projection plane of the horizontal plane, the return air guiding structure includes a straight section between two adjacent return air inlets and a straight section and / or a curved section between the return air inlet and the heat exchanger.

[0027] In some implementations...

[0028] Within the horizontal projection plane, the total length of the plurality of return air inlets extending in a direction parallel to the fan axis is less than the length L of the heat exchanger extending in a direction parallel to the fan axis. z The total length of the plurality of return air inlets extending in a direction parallel to the fan axis is greater than the length L of the fan extending in the fan axis direction. f， The return air guide structure that is relatively close to the longitudinal end of the plurality of return air inlets bends and extends toward the longitudinal end of the heat exchanger, and the return air guide structure that is relatively close to the middle of the longitudinal direction of the plurality of return air inlets also bends and extends toward the longitudinal end of the heat exchanger. However, the bending angle of the return air guide structure that is relatively close to the longitudinal end of the plurality of return air inlets is larger than the bending angle of the return air guide structure that is relatively close to the middle of the longitudinal direction of the plurality of return air inlets.

[0029] In some implementations...

[0030] The return air inlet includes a first return air inlet, a second return air inlet, a third return air inlet, a fourth return air inlet, and a fifth return air inlet, which are arranged at intervals along a direction parallel to the axis of the fan.

[0031] The return air guiding structure includes a first guide plate, a second guide plate, a third guide plate, and a fourth guide plate arranged sequentially at intervals along a direction parallel to the fan axis. The first guide plate extends from a position between the first return air inlet and the second return air inlet towards one end of the length of the heat exchanger. The section of the first guide plate between the first return air inlet and the second return air inlet is a straight section, and the bending angle of the section of the first guide plate between the first return air inlet and the heat exchanger relative to the straight section of the first guide plate is a first angle.

[0032] The second air guide plate extends from the position between the second return air inlet and the third return air inlet toward one end of the length of the heat exchanger. The section of the second air guide plate between the second return air inlet and the third return air inlet is a straight section. The bending angle of the section of the second air guide plate between the second return air inlet and the heat exchanger relative to the straight section of the second air guide plate is a second angle, and the first angle is greater than the second angle.

[0033] The third air guide plate extends from the position between the third return air inlet and the fourth return air inlet towards the other end of the length of the heat exchanger. The section of the third air guide plate between the third return air inlet and the fourth return air inlet is a straight section, and the bending angle of the section of the third air guide plate between the third return air inlet and the heat exchanger relative to the straight section of the third air guide plate is a third angle.

[0034] The fourth air guide plate extends from the position between the fourth return air inlet and the fifth return air inlet toward the other end of the length of the heat exchanger. The section of the fourth air guide plate between the fourth return air inlet and the fifth return air inlet is a straight section. The bending angle of the section of the fourth air guide plate between the fourth return air inlet and the heat exchanger relative to the straight section of the fourth air guide plate is a fourth angle, and the fourth angle is greater than the third angle.

[0035] In some implementations...

[0036] Within the horizontal projection plane, the first return air inlet and the fifth return air inlet are symmetrically arranged relative to the third return air inlet, and the second return air inlet and the fourth return air inlet are symmetrically arranged relative to the third return air inlet. The length centerline of the third return air inlet coincides with the centerline perpendicular to the fan axis.

[0037] In some implementations...

[0038] The area of ​​the air blown out of the first return air outlet covered by the air through the first air guide plate is S1. The area of ​​the air blown out of the second return air outlet covered by the air through the first air guide plate and the second air guide plate is S2, and S1 / S2 = 60%-85%. The area of ​​the air blown out of the third return air outlet covered by the air through the second air guide plate and the third air guide plate is S3, and S2 / S3 = 60%-85%.

[0039] The area of ​​the air blown out of the fourth return air outlet covering the heat exchanger is S4 due to the guiding effect of the third and fourth air guide plates. The area of ​​the air blown out of the fifth return air outlet covering the heat exchanger is S5 due to the guiding effect of the fourth air guide plate. S4 / S3 = 60%-85% and S5 / S4 = 60%-85%.

[0040] In some implementations...

[0041] The heat exchanger is an evaporator, and the heat exchanger is a plate heat exchanger. The heat exchange plates of the plate heat exchanger are inclined to the horizontal plane, and the inclination angle is between 6° and 25°.

[0042] In some implementations...

[0043] The housing includes a chassis, and a volute is also provided inside the housing. The fan is located inside the volute and downstream of the heat exchanger along the airflow direction. The volute and the chassis are integrally formed. An air outlet is provided on the chassis opposite to the fan and faces the interior of the vehicle. The return air outlet is also provided on the chassis and communicates with the interior of the vehicle.

[0044] In some implementations...

[0045] The chassis is formed into a water receiving structure below the heat exchanger. The lower end of the water receiving structure is connected to a drain outlet, which is connected to an external drain pipe to discharge condensate from the shell.

[0046] The roof-mounted parking air conditioner provided by this invention has the following beneficial effects:

[0047] 1. This invention, by setting a return air guiding structure inside the housing, with at least a portion of the structure located between the return air inlet and the heat exchanger, effectively guides the air drawn in from the return air inlet to different positions on the heat exchanger. This results in a more uniform airflow distribution within the heat exchanger. Compared to existing solutions where uneven airflow distribution occurs due to unequal lengths of the fan, heat exchanger, and return air inlet, this invention improves the uniformity of airflow distribution on the heat exchanger. Consequently, the heat exchange is more uniform, improving heat exchange capacity, enhancing the cooling / heating performance of the roof-mounted parking air conditioner, and improving the uniformity of airflow velocity in different parts of the evaporator. This further enhances the uniformity of heat exchange in different parts of the evaporator, allowing for better evaporator performance and solving the problem of uneven heat exchange in the evaporator.

[0048] 2. The present invention also ensures that the static pressure ratio Y of the airflow within the heat exchanger range satisfies the relationship X (relative length ratio) by setting the return air guide structure: Y = 1 - β²X 2 -β3X; where X=(L x-(β1*L f ) / 2) / ((β1*L f The invention enables the static pressure ratio of the airflow within the heat exchanger to satisfy a downward-opening parabolic distribution, with the maximum static pressure ratio on the central plane and a slowly descending distribution pattern from the central plane to both sides. This results in a highly uniform airflow distribution within the heat exchanger. Compared to existing solutions where uneven airflow distribution is caused by unequal lengths of the fan, heat exchanger, and return air inlet, this invention significantly improves the uniformity of airflow distribution on the heat exchanger. This leads to more uniform heat exchange, increased heat exchange capacity, improved cooling / heating performance of the roof-mounted parking air conditioner, and improved wind speed uniformity in different parts of the evaporator, thereby enhancing the heat exchange uniformity of each part of the evaporator, better utilizing evaporator performance, and solving the problem of uneven evaporator heat exchange.

[0049] 3. The present invention further improves the uniformity of airflow distribution in all parts of the heat exchanger by guiding the airflow through the first air guide plate, ensuring that the area S1 of the first return air outlet blown onto the heat exchanger and the area S2 of the second return air outlet (guided by the first and second air guide plates) blown onto the heat exchanger satisfy S1 / S2 = 60%-85%, and the area S2 of the third return air outlet (guided by the second and third air guide plates) blown onto the heat exchanger satisfy S2 / S3 = 60%-85%. This results in the airflow being maximized in the middle of the heat exchanger due to the action of the air guide plates, and the airflow gradually decreasing towards both ends of the length. This greatly improves the uniformity of airflow distribution in all parts of the heat exchanger, further enhances the heat exchange uniformity in all parts of the evaporator, and better utilizes the performance of the evaporator.

[0050] 4. This invention also improves cooling capacity by setting the heat exchanger as an inclined plate heat exchanger, which increases the evaporator height within the limited height of the outdoor unit, increasing the airflow area by 25%-33%, thus increasing the heat exchange area and improving cooling capacity. Cooling capacity is increased by 4%-9% under various operating conditions, maximizing the evaporator's airflow area within a limited space. Furthermore, the integrated design of the chassis and the lower volute of the internal fan (centrifugal) reduces the installation steps of pre-installing the internal fan and then assembling it, simplifying the production process. Simultaneously, the internal fan no longer has an installation gap with the chassis, improving the waterproofness of the evaporator chamber and further simplifying the production process. Finally, the invention uses an externally connectable drain outlet to prevent air mixing with the vehicle's airflow, effectively reducing the cooling outlet temperature by 0.7℃-2.9℃ under various operating conditions, improving cooling sensation and user experience, and solving problems such as capacity reduction and poor user experience caused by mixed airflow. Attached Figure Description

[0051] Figure 1 This is a top view of the overhead parking air conditioner of the present invention;

[0052] Figure 2 This is a schematic diagram of the left-side cross-sectional view of the roof-mounted parking air conditioner of the present invention;

[0053] Figure 3 This is a schematic diagram of the installation structure of the roof-mounted parking air conditioner of the present invention;

[0054] Figure 4 This is a top-view diagram of the airflow distribution of the roof-mounted parking air conditioner of the present invention.

[0055] The attached figures are labeled as follows:

[0056] 210. Shell; 310. Fan; 510. Heat exchanger; 610. Return air guide structure; 611. First air guide plate; 612. Second air guide plate; 613. Third air guide plate; 614. Fourth air guide plate; 710. Drain outlet; 711. First drain outlet; 712. Second drain outlet; 810. Return air inlet; 811. First return air inlet; 812. Second return air inlet; 813. Third return air inlet; 814. Fourth return air inlet; 815. Fifth return air inlet; 111. Volute; 410. Evaporator foam; 420. Evaporation chamber; 910. Indoor unit; 920. Outdoor fan; 1010. Truck. Detailed Implementation

[0057] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0058] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0059] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0060] In the description of this invention, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is generally based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this invention; the directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0061] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0062] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0063] like Figure 1-4As shown, the present invention provides a roof-mounted parking air conditioner, which includes:

[0064] The system comprises a housing 210, a return air inlet 810, a heat exchanger 510, a fan 310, and a return air guide structure 610. The return air inlet 810 is disposed on the housing 210, the heat exchanger 510 is disposed inside the housing 210, and the fan 310 is disposed inside the housing 210 to drive airflow from the return air inlet 810 into the housing 210 and exchange heat with the heat exchanger 510. The return air guide structure 610 is disposed inside the housing 210 and is at least partially located between the return air inlet 810 and the heat exchanger 510. The return air guide structure 610 can guide the airflow from the return air inlet 810 to different positions on the heat exchanger 510.

[0065] This invention, by incorporating a return air guiding structure within the housing, with at least a portion of the structure located between the return air inlet and the heat exchanger, effectively directs the air drawn in through the return air inlet to different locations on the heat exchanger. This results in a more uniform airflow distribution within the heat exchanger. Compared to existing solutions where uneven airflow distribution occurs due to unequal lengths of the fan, heat exchanger, and return air inlet, this invention improves the uniformity of airflow distribution on the heat exchanger. Consequently, it leads to more uniform heat exchange, enhanced heat exchange capacity, improved cooling / heating performance of the roof-mounted parking air conditioner, and improved uniformity of airflow velocity across the evaporator. This further enhances the heat exchange uniformity across the evaporator, allowing for better evaporator performance and resolving the problem of uneven evaporator heat exchange.

[0066] In some embodiments, a center plane perpendicular to the axis is made at a position halfway along the axial direction of the fan, and the distance between different positions on the heat exchanger 510 and the center plane is L. x And:

[0067] X = (L x -(β1*L f ) / 2) / ((β1*L f ) / 2);

[0068] The return air guide structure 610 ensures that the static pressure ratios Y and X of the airflow within the heat exchanger 510 satisfy the following relationship:

[0069] Y = 1 - β²X 2 -β3X;

[0070] in:

[0071] L z The length of the heat exchanger extending in a direction parallel to the fan axis;

[0072] Lf The length of the fan extending along its axial direction;

[0073] β1: Effective return air correction factor;

[0074] β2: Auxiliary correction coefficient for static pressure ratio curve;

[0075] β3: Static pressure ratio curve correction factor.

[0076] This invention, by incorporating a return air guiding structure within the casing, with at least a portion of the structure located between the return air inlet and the heat exchanger, effectively directs the air drawn in through the return air inlet to different positions on the heat exchanger. Furthermore, the arrangement of the return air guiding structure ensures that the static pressure ratio Y of the airflow within the heat exchanger range satisfies the relationship X (relative length ratio): Y = 1 - β²X. 2 -β3X; where X=(L x -(β1*L f ) / 2) / ((β1*L f The invention enables the static pressure ratio of the airflow within the heat exchanger to satisfy a downward-opening parabolic distribution, with the maximum static pressure ratio on the central plane and a slowly descending distribution pattern from the central plane to both sides. This results in a highly uniform airflow distribution within the heat exchanger. Compared to existing solutions where uneven airflow distribution is caused by unequal lengths of the fan, heat exchanger, and return air inlet, this invention significantly improves the uniformity of airflow distribution on the heat exchanger. This leads to more uniform heat exchange, increased heat exchange capacity, improved cooling / heating performance of the roof-mounted parking air conditioner, and improved wind speed uniformity in different parts of the evaporator, thereby enhancing the heat exchange uniformity of each part of the evaporator, better utilizing evaporator performance, and solving the problem of uneven evaporator heat exchange.

[0077] The outer casing (shell 210) of the present invention is preferably the outer casing of the whole unit; the evaporation chamber 420 is a cavity formed by combining the evaporator foam 410 with the chassis and is isolated from the outdoor unit. Judging from the principle of conventional air conditioning system, it belongs to the indoor unit of air conditioner. The evaporation chamber 420 contains an internal fan (i.e., fan 310), heat exchanger 510, return air guide structure 610, drain outlet 710, and return air outlet 810.

[0078] In some implementations...

[0079] The heat exchanger 510 extends for a length L in a direction parallel to the fan axis. z Greater than the length L of the fan extending along its axial direction f L z >L f And L z ≤3β1L f .

[0080] This is the preferred structural form of the present invention, where the length of the heat exchanger is greater than the length of the fan. Typically, the fan's volume and length are smaller than the length of the heat exchanger; it only needs to drive the airflow and does not need to be very long. However, this is also the main factor leading to uneven distribution of airflow across different positions on the heat exchanger. The present invention, by setting a return air guiding structure, can guide the air drawn in from the return air inlet to different positions on the heat exchanger. In particular, the static pressure ratio Y of the airflow satisfies the relationship with X (relative length ratio): Y = 1 - β²X 2 -β3X can maximize the uniformity of airflow distribution on the heat exchanger, and L z ≤3β1L f Limiting the length of the heat exchanger can prevent the structure of the air guide plate from being too long, which would make it impossible to guarantee a relatively uniform distribution of airflow on the heat exchanger. Therefore, limiting its length to a certain extent can further improve the uniformity of airflow distribution on the heat exchanger and further improve the performance of the evaporator.

[0081] Figure 3 The diagram shows the installation of the roof-mounted integrated parking air conditioner of the present invention. The roof-mounted integrated parking air conditioner indoor unit 910 is placed indoors through the sunroof of the truck 1010 (tractor, heavy truck). The dimensions (length and width) of the roof-mounted integrated parking air conditioner indoor unit 910 are limited by the dimensions of the sunroof of the truck 1010 (tractor, heavy truck). The length and width of the roof-mounted integrated parking air conditioner indoor unit 910 are smaller than the length and width of the sunroof of the truck 1010 (tractor, heavy truck).

[0082] Figure 1 The diagram shown is a top-view view of the indoor unit of a roof-mounted integrated parking air conditioner. The total length of the return air vent 810 of the evaporator chamber is less than the length of the indoor unit 910 of the roof-mounted integrated parking air conditioner.

[0083] In some implementations...

[0084] L z The value range is 600-1000mm, L f The values ​​of β1 and β2 range from 250 to 400 mm, β1 range from 1.1 to 1.4, β2 range from 0.5 to 0.75, and β3 range from 0.15 to 0.3. More preferably, β1 is 1.3, β2 is 0.6, and β3 is 0.2.

[0085] This is the variable L of the present invention. z and L f The preferred range of values ​​for parameters β1, β2 and β3, and the preferred range of values ​​for parameters β3, β4 and β5, can further improve the uniformity of airflow distribution on the heat exchanger, make the heat exchanger more uniform, and further improve the cooling / heating performance of the roof-mounted parking air conditioner.

[0086] In some implementations...

[0087] There are two or more return air inlets 810, which are distributed sequentially at intervals along the length of the heat exchanger 510. There are also two return air guide structures 610, at least a portion of which is disposed between two adjacent return air inlets 810. At least a portion of which extends from the return air inlet 810 to connect with or be spaced a predetermined distance from the heat exchanger 510.

[0088] This invention utilizes two or more return air vents distributed sequentially and at intervals along the horizontal direction of the heat exchanger, along with two or more corresponding return air guiding structures. These structures extend from between adjacent return air vents to either connect with or be spaced a predetermined distance from the heat exchanger. This effectively separates the airflow from the two return air vents, guiding the airflow from one vent to a designated heat exchanger area, and vice versa. The arrangement of the return air vents and guiding structures further enhances the uniformity of airflow distribution on the heat exchanger, improves the uniformity of airflow velocity across the evaporator, enhances the heat exchange uniformity of the heat exchanger, and ultimately improves the cooling / heating performance of the roof-mounted parking air conditioner.

[0089] In some implementations...

[0090] Within the horizontal projection plane, the return air guiding structure 610 includes a straight segment between two adjacent return air inlets 810 and a straight segment and / or a curved segment between the return air inlet 810 and the heat exchanger 510. This is a further preferred structural form of the return air guiding structure of the present invention. By including the straight segment between two adjacent return air inlets, the airflow between the two return air inlets can be effectively separated. The straight segment and / or curved segment between the return air inlet and the heat exchanger can further guide the airflow introduced by the separated return air inlets to different positions or different areas on the heat exchanger, improving the separation performance and the uniformity of the airflow guided to the heat exchanger, thereby further improving the heat exchange performance of the heat exchanger.

[0091] In some implementations...

[0092] Within the horizontal projection plane, the total length of the plurality of return air inlets 810 extending in a direction parallel to the fan axis is less than the length L of the heat exchanger extending in a direction parallel to the fan axis. z The total length of the plurality of return air inlets 810 extending in a direction parallel to the fan axis is greater than the length L of the fan extending in the fan axis direction. fThe return air guide structure 610 that is relatively close to the longitudinal end of the plurality of return air inlets 810 bends and extends toward the longitudinal end of the heat exchanger. The return air guide structure 610 that is relatively close to the middle of the longitudinal direction of the plurality of return air inlets 810 also bends and extends toward the longitudinal end of the heat exchanger. However, the bending angle of the return air guide structure 610 that is relatively close to the longitudinal end of the plurality of return air inlets 810 is larger than the bending angle of the return air guide structure 610 that is relatively close to the middle of the longitudinal direction of the plurality of return air inlets 810.

[0093] This is a further preferred structural form of the multiple return air inlets, heat exchangers, and fans of the present invention. The length of the multiple return air inlets extending in a direction parallel to the fan axis is less than the length of the heat exchanger but greater than the length of the fan. This limits the length or number of return air inlets due to structural constraints, preventing them from being too long or too numerous. Furthermore, different airflow guiding structures can be formed at different locations to provide airflow guidance for different areas of the heat exchanger. For example, for areas near the ends of the heat exchanger along its length, the corresponding return air guiding structure needs to have a larger bending angle, while for areas near the middle of the heat exchanger along its length, the corresponding return air guiding structure needs to have a smaller bending angle. Figure 1 and 4 As shown, separate airflow guides are created for the end and middle regions of the heat exchanger to achieve uniform airflow distribution. The bending angle here refers to the angle at which the curved segment connected to the straight segment of the return air guide structure bends in a certain direction, based on the straight segment between two adjacent return air inlets. For example... Figure 1 and 4 As shown, the bending angles of the first and fourth air guide plates are acute angles of approximately 75°, while the bending angles of the second and third air guide plates are acute angles of approximately 45°.

[0094] In some implementations...

[0095] The return air inlet 810 includes a first return air inlet 811, a second return air inlet 812, a third return air inlet 813, a fourth return air inlet 814, and a fifth return air inlet 815, which are arranged at intervals along a direction parallel to the axis of the fan.

[0096] The return air guiding structure 610 includes a first guide plate 611, a second guide plate 612, a third guide plate 613, and a fourth guide plate 614 arranged sequentially at intervals along a direction parallel to the fan axis. The first guide plate 611 extends from a position between the first return air inlet 811 and the second return air inlet 812 toward one end of the length of the heat exchanger 510. The segment of the first guide plate 611 between the first return air inlet 811 and the second return air inlet 812 is a straight segment. The bending angle of the segment of the first guide plate 611 between the first return air inlet 811 and the heat exchanger 510 relative to the straight segment of the first guide plate 611 is a first angle.

[0097] The second air guide plate 612 extends from the position between the second return air inlet 812 and the third return air inlet 813 toward one end of the length of the heat exchanger. The section of the second air guide plate 612 between the second return air inlet 812 and the third return air inlet 813 is a straight section. The bending angle of the section of the second air guide plate 612 between the second return air inlet 812 and the heat exchanger relative to the straight section of the second air guide plate 612 is a second angle, and the first angle is greater than the second angle.

[0098] The third air guide plate 613 extends from the position between the third return air inlet 813 and the fourth return air inlet 814 towards the other end of the length of the heat exchanger. The segment of the third air guide plate 613 between the third return air inlet 813 and the fourth return air inlet 814 is a straight segment. The bending angle of the segment of the third air guide plate 613 between the third return air inlet 813 and the heat exchanger 510 relative to the straight segment of the third air guide plate 613 is a third angle.

[0099] The fourth air guide plate 614 extends from the position between the fourth return air inlet 814 and the fifth return air inlet 815 toward the other end of the length of the heat exchanger 510. The section of the fourth air guide plate 614 between the fourth return air inlet 814 and the fifth return air inlet 815 is a straight section. The bending angle of the section of the fourth air guide plate 614 between the fourth return air inlet 814 and the heat exchanger 510 relative to the straight section of the fourth air guide plate 614 is a fourth angle, and the fourth angle is greater than the third angle.

[0100] This is a further preferred structural form of the return air inlet and return air guide structure of the present invention, namely, the preferred embodiment of the present invention: the return air inlet includes a structure with a first, second, third, fourth, and fifth return air inlet, and the return air guide structure includes a structure with a first, second, third, and fourth guide plate. The third return air inlet is opposite to the area of ​​the fan. The first and second return air inlets are located to the left of the third return air inlet as shown in the figure, and the fourth and fifth return air inlets are located to the right of the third return air inlet as shown in the figure. The first guide plate is located between the first and second return air inlets to guide the airflow of the first return air inlet, and the second guide plate is located between the second and third return air inlets to work together with the first guide plate. The third air guide plate is located between the third and fourth air guide plates, and together with the second air guide plate, it guides the airflow at the third air guide plate. The fourth air guide plate is located between the fourth and fifth air guide plates, and together with the third air guide plate, it guides the airflow at the fourth air guide plate. The fourth air guide plate also guides the airflow at the fifth air guide plate, and forms different bending angles as mentioned above, so as to create different guiding effects on the airflow at different positions on the heat exchanger, further improving the uniformity of airflow distribution on the heat exchanger, thereby improving the heat exchange performance of the heat exchanger and improving the cooling / heating performance of the roof-mounted parking air conditioner.

[0101] Figure 4 The diagram shown is a top-view schematic of the return air distribution of the top-mounted integrated parking air conditioner of the present invention. The design of the return air inlet guide device within the evaporator cavity is illustrated. The guide device is a plastic guide plate that can be integrated with the chassis. The first guide plate 611, the second guide plate 612, the third guide plate 613, and the fourth guide plate 614 separate the first return air inlet 811, the second return air inlet 812, the third return air inlet 813, the fourth return air inlet 814, and the fifth return air inlet 815 of the evaporator cavity.

[0102] The first air guide plate 611 separates the first return air inlet 811 of the evaporation chamber from the second return air inlet 812 of the evaporation chamber, so that the return air of the first return air inlet 811 of the evaporation chamber only flows through the left side area of ​​the first air guide plate 611 and exchanges heat with the left side of the evaporator.

[0103] The second air guide plate 612 separates the second return air inlet 812 of the evaporation chamber from the third return air inlet 813 of the evaporation chamber, so that the return air of the second return air inlet 812 of the evaporation chamber only flows through the area between the first air guide plate 611 and the second air guide plate 612, and exchanges heat with the left-center side of the evaporator.

[0104] The third air guide plate 613 separates the third return air inlet 813 of the evaporator from the fourth return air inlet 814 of the evaporation chamber, so that the return air of the third return air inlet 813 of the evaporation chamber only flows through the area between the second air guide plate 612 and the third air guide plate 613, and exchanges heat with the middle part of the evaporator.

[0105] The fourth air guide plate 614 separates the fourth return air inlet 814 of the evaporator cavity from the fifth return air inlet 815 of the evaporator; so that the return air of the fourth return air inlet 814 of the evaporator cavity flows only through the area between the third air guide plate 613 and the fourth air guide plate 614, and exchanges heat with the right-side middle side of the evaporator; so that the return air of the fifth return air inlet 815 of the evaporator cavity flows only through the right side area of ​​the fourth air guide plate 614, and exchanges heat with the right side of the evaporator.

[0106] In some implementations...

[0107] Within the horizontal projection plane, the first return air inlet 811 and the fifth return air inlet 815 are symmetrically arranged relative to the third return air inlet 813, and the second return air inlet 812 and the fourth return air inlet 814 are symmetrically arranged relative to the third return air inlet 813. The length centerline of the third return air inlet 813 coincides with the centerline perpendicular to the fan axis.

[0108] This is a further preferred structural form of the five return air inlets of the present invention, namely, the third return air inlet is located in the middle position, and its length centerline coincides with the centerline perpendicular to the fan axis, thereby further ensuring the uniformity of airflow distribution to different areas of the heat exchanger, improving heat exchange performance, and improving the cooling / heating performance of the parking air conditioner.

[0109] In some implementations...

[0110] The area of ​​the air blown out of the first return air outlet 811 by the first air guide plate 611 covering the heat exchanger is S1. The area of ​​the air blown out of the second return air outlet 812 by the first air guide plate 611 and the second air guide plate 612 covering the heat exchanger is S2, and S1 / S2 = 60%-85%. The area of ​​the air blown out of the third return air outlet 813 by the second air guide plate 612 and the third air guide plate 613 covering the heat exchanger is S3, and S2 / S3 = 60%-85%.

[0111] The area of ​​the air blown out of the fourth return air outlet 814 covered by the air through the guiding effect of the third air guide plate 613 and the fourth air guide plate 614 is S4. The area of ​​the air blown out of the fifth return air outlet 815 covered by the air through the guiding effect of the fourth air guide plate 614 is S5. S4 / S3 = 60%-85% and S5 / S4 = 60%-85%.

[0112] This invention further ensures that the area S1 of the first return air outlet blowing onto the heat exchanger is equal to the area S2 of the second return air outlet (due to the guiding effect of the first and second guide air outlets) blowing onto the heat exchanger, and that the area S2 of the third return air outlet (due to the guiding effect of the second and third guide air outlets) blowing onto the heat exchanger is equal to the area S2 of the third return air outlet (due to the guiding effect of the second and third guide air outlets), resulting in an unequal distribution of the evaporator area controlled by each return air outlet: the first return air outlet 811 and the fifth return air outlet 811... The evaporator area of ​​the air outlet 815 is symmetrical and the same as that of the second return air outlet 812 and the fourth return air outlet 814, which are also symmetrical and the same as those of the evaporator area of ​​the third return air outlet 813 in the evaporation chamber. This results in the air volume being the largest in the middle of the heat exchanger due to the effect of the air guide plate, and the air volume gradually decreasing towards both ends of the length. Therefore, the uniformity of airflow distribution in all parts of the heat exchanger is greatly improved, further enhancing the heat exchange uniformity of all parts of the evaporator and better utilizing the evaporator performance.

[0113] In some implementations...

[0114] The heat exchanger 510 is an evaporator, and it is a plate heat exchanger. The heat exchange plates of the plate heat exchanger are inclined relative to the horizontal plane, with an inclination angle between 6° and 25°. This invention also allows for increasing the evaporator height within the limited height of the outdoor unit by setting the heat exchanger as an inclined plate heat exchanger, increasing the windward area by 25%-33%, increasing the heat exchange area, and thus improving the cooling capacity. Cooling capacity under various operating conditions is increased by 4%-9%, maximizing the evaporator's windward area within a limited space.

[0115] Figure 1 The diagram shown is a top-down view of a roof-mounted integrated parking air conditioner, with the heat exchanger 510 tilted 6°-25° towards the inward fan direction.

[0116] In some implementations...

[0117] The housing 210 includes a chassis, and a volute 111 is also provided inside the housing 210. The fan 310 is disposed inside the volute 111 and is located downstream of the heat exchanger 510 along the airflow direction. The volute 111 is integrally formed with the chassis. An air outlet is provided on the chassis opposite to the fan 310 and faces the interior of the vehicle. The return air vent 810 is also provided on the chassis and communicates with the interior of the vehicle.

[0118] The present invention also integrates the chassis and the lower volute of the internal fan (centrifugal) into a single design. Preferably, the volute 111 integrated with the chassis is the lower volute of the internal fan, which is molded as an integral part of the chassis. This reduces the installation steps of pre-assembling the internal fan and then assembling it into a final assembly, thus simplifying the production process. At the same time, the internal fan no longer has an installation gap with the chassis, improving the waterproofness of the evaporation chamber and reducing installation steps to simplify the production process.

[0119] In some implementations...

[0120] A water receiving structure is formed on the chassis and below the heat exchanger 510. The lower end of the water receiving structure is connected to a drain outlet 710, which is connected to an external drain pipe to discharge condensate from the housing 210.

[0121] This invention also avoids mixing of air from outside the vehicle by using an externally connectable drain outlet, thereby effectively reducing the cooling air outlet temperature by 0.7℃-2.9℃ under various operating conditions, improving the cooling sensation and user experience, and solving problems such as reduced cooling capacity and poor user experience caused by air mixing.

[0122] The first drain outlet 711 and the second drain outlet 712 are located on both sides of the chassis near the upper edge of the drainage trough (as shown by the dotted line);

[0123] Figure 2 The diagram shown is a left-side cross-sectional view of the roof-mounted integrated parking air conditioner. Its drain outlet 710 faces downwards and can be connected to an external drain outlet 710. The outer diameter of the drain outlet 710 is φ7-φ20mm and the height is 8-15mm. It can be connected to the drain pipe that comes with the sunroof or a specially equipped drain pipe. Due to the small diameter and long length of the drain pipe, the wind resistance is large, which is sufficient to counteract the static pressure generated by the evaporator chamber when it is turned on, thereby avoiding the mixing of air from outside the vehicle and effectively improving the cooling sensation and user experience.

[0124] Conventional roof-mounted integrated parking air conditioners have relatively low performance, mainly due to the following two reasons:

[0125] First, the overall machine height limits the evaporator height, thus restricting the overall machine performance.

[0126] Conventional roof-mounted integrated parking air conditioner evaporators are typically placed vertically. Due to limitations in the overall unit height, the evaporator height is also limited, resulting in a limited evaporator return air area. To improve system performance without changing the overall unit height, it is necessary to increase the evaporator return air area. There are two ways to increase the return air area:

[0127] 1. The evaporator is tilted to increase its height. If the evaporator is tilted, the condensate on the evaporator will fall to the vicinity of the lower volute of the inner fan, and then seep out through the connection between the lower volute of the inner fan and the chassis, flowing through the air outlet and falling into the room. Therefore, this invention adopts an integrated design of chassis and lower volute of inner fan, reducing the installation steps of pre-installing the inner fan and then assembling it into the final assembly, thus simplifying the production process. Due to the integrated design, there is no longer an installation gap between the inner fan and the chassis, raising the threshold for condensate to enter the vehicle through the inner fan.

[0128] 2. Increase evaporator length: Because the size of the skylight limits the size of the indoor unit, it also limits the size of the return air vent. If the evaporator length is increased, the two ends of the evaporator will be far from the return air vent, resulting in low airflow and poor heat exchange, which cannot be fully utilized. Therefore, this invention adopts a return air guide plate design to solve the problem of different return air velocities caused by different static pressures in different parts of the evaporator (static pressure decreases as it moves away from the indoor fan). By distributing the return air vents in different areas, the heat exchange uniformity of the evaporator is balanced, thereby improving the heat exchange efficiency of the evaporator.

[0129] Second, because the outdoor unit is located on the roof of the vehicle, the drain outlet discharges condensate onto the roof and is connected to the outside environment. When the air conditioner is turned on, the internal fan creates a negative pressure chamber in the evaporator, which causes the drain outlet to draw in high-temperature outside air, mixes with the air cooled by the evaporator, and blows it out from the air outlet, resulting in reduced performance.

[0130] This invention uses an externally connectable drain outlet to connect with the sunroof's built-in drain pipe or a specially designed drain pipe. Because the drain pipe has a small diameter and long length, it has high wind resistance, which is sufficient to counteract the static pressure generated by the evaporator chamber when it is turned on, thereby avoiding the mixing of air from outside the vehicle and effectively improving the cooling sensation and user experience.

[0131] 1. This invention, through the design of the air return vent guide device inside the evaporator chamber, preferably a plastic air guide plate that can be integrated with the chassis, addresses the issue of varying distances between the air return vents and the fan, resulting in low air velocity and poor heat exchange on the left and right sides of the evaporator. The uneven distribution of the evaporator area through each air return vent improves the air velocity across the evaporator surface, enhancing the uniformity of air velocity across different parts of the evaporator. This, in turn, improves the heat exchange uniformity of the evaporator, allowing for better performance and maximizing its heat exchange effect. Consequently, it increases the cooling capacity by 9%-17% and energy efficiency by 5%-11% under various operating conditions.

[0132] 2. This invention features an evaporator tilted at an angle of 6°-25°. By tilting the evaporator, the height of the evaporator is increased within the limited height of the outdoor unit, increasing the windward area by 25%-33%, thus increasing the heat exchange area and improving the cooling capacity. The cooling capacity under various operating conditions is increased by 4%-9%.

[0133] 3. This invention integrates the chassis and the lower volute of the internal fan (centrifugal fan) into a single design. The chassis is designed with the lower volute of the internal fan included in the mold. This reduces the installation steps of pre-assembling the internal fan and then assembling it into a final assembly, thus simplifying the production process. At the same time, the internal fan no longer has an installation gap with the chassis, improving the waterproofness of the evaporation chamber.

[0134] 4. This invention features an externally connectable drain outlet, preferably with an outer diameter of φ7-φ20mm and a height of 8-15mm. It can connect to the sunroof's built-in drain pipe or a specially designed drain pipe. Due to the small diameter and long length of the drain pipe, the wind resistance is large enough to counteract the static pressure generated by the evaporator chamber when it is turned on, thereby avoiding the mixing of air from outside the vehicle and effectively reducing the cooling air outlet temperature. The air outlet temperature is reduced by 0.7℃-2.9℃ under various operating conditions, which can effectively improve the cooling sensation and user experience.

[0135] This invention solves the following technical problems:

[0136] 1. Solved the problem of uneven heat exchange in the evaporator;

[0137] 2. Solving the problem of not being able to increase the evaporator's frontal area within a limited space;

[0138] 3. Resolve issues such as reduced capacity and poor user experience caused by mixed airflow;

[0139] 4. Solve the problem of complicated installation steps and complex production processes.

[0140] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention. The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the protection scope of the present invention.

Claims

1. A roof-mounted parking air conditioner, characterized in that: include: The system comprises a housing (210), a return air inlet (810), a heat exchanger (510), a fan (310), and a return air guide structure (610). The return air inlet (810) is disposed on the housing (210), the heat exchanger (510) is disposed inside the housing (210), and the fan (310) is disposed inside the housing (210) to drive airflow from the return air inlet (810) into the housing (210) and exchange heat with the heat exchanger (510). The return air guide structure (610) is disposed inside the housing (210) and is at least partially located between the return air inlet (810) and the heat exchanger (510). The return air guide structure (610) can guide the airflow from the return air inlet (810) to different positions on the heat exchanger (510). A center plane perpendicular to the axis is made at a position half the length of the fan axis. The arrangement of the return air guide structure (610) ensures that the static pressure ratio Y of the airflow within the heat exchanger (510) satisfies the following relationship with the relative length ratio X: Y=1-β2X 2 -β3X ; in: Relative length ratio X: is the length position of a specific location on the heat exchanger (510) relative to the center plane; β2: Auxiliary correction coefficient for static pressure ratio curve; β3: Correction factor for static pressure ratio curve; There are two or more return air inlets (810), and the two or more return air inlets (810) are distributed sequentially at intervals along the length direction of the heat exchanger (510). There are also two or more return air guide structures (610). At least a part of the return air guide structure (610) is disposed between two adjacent return air inlets (810), and at least a part of the return air guide structure (610) extends from the return air inlet (810) to connect with the heat exchanger (510) or to be spaced at a predetermined distance from the heat exchanger (510). The return air inlet (810) includes a first return air inlet (811), a second return air inlet (812), a third return air inlet (813), a fourth return air inlet (814), and a fifth return air inlet (815) arranged sequentially at intervals along a direction parallel to the fan axis. The return air guiding structure (610) includes a first air guide plate (611), a second air guide plate (612), a third air guide plate (613), and a fourth air guide plate (614) arranged sequentially at intervals along a direction parallel to the fan axis. The area of ​​the air blown out by the first return air port (811) through the guiding effect of the first air guide plate (611) covering the heat exchanger is S1. The area of ​​the air blown out by the second return air port (812) through the guiding effect of the first air guide plate (611) and the second air guide plate (612) covering the heat exchanger is S2, and S1 / S2=60%~85%. The area of ​​the air blown out by the third return air port (813) through the guiding effect of the second air guide plate (612) and the third air guide plate (613) covering the heat exchanger is S3, and S2 / S3=60%~85%. The area of ​​the air blown out by the fourth return air outlet (814) through the guiding effect of the third air guide plate (613) and the fourth air guide plate (614) covering the heat exchanger is S4, and the area of ​​the air blown out by the fifth return air outlet (815) through the guiding effect of the fourth air guide plate (614) covering the heat exchanger is S5, with S4 / S3=60%~85% and S5 / S4=60%~85%.

2. The roof-mounted parking air conditioner according to claim 1, characterized in that: The distance between different locations on the heat exchanger (510) and the center plane is L. x And: X=(L x -(β1*L f ) / 2) / ((β1*L f ) / 2); in: L f The length of the fan extending along its axial direction; β1: Effective return air correction coefficient.

3. The roof-mounted parking air conditioner according to claim 2, characterized in that: L z The length of the heat exchanger extending in a direction parallel to the fan axis; The heat exchanger (510) extends for a length L in a direction parallel to the fan axis. z Greater than the length L of the fan extending along its axial direction f L z >L f And L z ≤3β1L f .

4. The roof-mounted parking air conditioner according to claim 3, characterized in that: L z The value range is 600~1000mm, L f The value range is 250~400mm, the value range of β1 is 1.1~1.4, the value range of β2 is 0.5~0.75, and the value range of β3 is 0.15~0.

3.

5. The roof-mounted parking air conditioner according to claim 1, characterized in that: Within the projection plane of the horizontal plane, the return air guide structure (610) includes a straight segment between two adjacent return air inlets (810) and a straight segment and / or a curved segment between the return air inlet (810) and the heat exchanger (510).

6. The roof-mounted parking air conditioner according to claim 5, characterized in that: Within the horizontal projection plane, the total length of the plurality of return air inlets (810) extending in a direction parallel to the fan axis is less than the length L of the heat exchanger extending in a direction parallel to the fan axis. z The total length of the plurality of return air inlets (810) extending in a direction parallel to the fan axis is greater than the length L of the fan extending in the fan axis direction. f The return air guide structure (610) that is relatively close to the longitudinal end of the plurality of return air inlets (810) bends and extends toward the longitudinal end of the heat exchanger. The return air guide structure (610) that is relatively close to the middle of the longitudinal direction of the plurality of return air inlets (810) also bends and extends toward the longitudinal end of the heat exchanger. However, the bending angle of the return air guide structure (610) that is relatively close to the longitudinal end of the plurality of return air inlets (810) is larger than the bending angle of the return air guide structure (610) that is relatively close to the middle of the longitudinal direction of the plurality of return air inlets (810).

7. The roof-mounted parking air conditioner according to claim 6, characterized in that: The first air guide plate (611) extends from the position between the first return air inlet (811) and the second return air inlet (812) toward one end of the length of the heat exchanger (510). The section of the first air guide plate (611) between the first return air inlet (811) and the second return air inlet (812) is a straight section. The bending angle of the section of the first air guide plate (611) between the first return air inlet (811) and the heat exchanger (510) relative to the straight section of the first air guide plate (611) is a first angle. The second air guide plate (612) extends from the position between the second return air inlet (812) and the third return air inlet (813) toward one end of the length of the heat exchanger (510). The section of the second air guide plate (612) between the second return air inlet (812) and the third return air inlet (813) is a straight section. The bending angle of the section of the second air guide plate (612) between the second return air inlet (812) and the heat exchanger (510) relative to the straight section of the second air guide plate (612) is a second angle, and the first angle is greater than the second angle. The third air guide plate (613) extends from the position between the third return air inlet (813) and the fourth return air inlet (814) toward the other end of the length of the heat exchanger (510). The section of the third air guide plate (613) between the third return air inlet (813) and the fourth return air inlet (814) is a straight section. The bending angle of the section of the third air guide plate (613) between the third return air inlet (813) and the heat exchanger (510) relative to the straight section of the third air guide plate (613) is a third angle. The fourth air guide plate (614) extends from the position between the fourth return air inlet (814) and the fifth return air inlet (815) toward the other end of the length of the heat exchanger (510). The section of the fourth air guide plate (614) between the fourth return air inlet (814) and the fifth return air inlet (815) is a straight section. The bending angle of the section of the fourth air guide plate (614) between the fourth return air inlet (814) and the heat exchanger (510) relative to the straight section of the fourth air guide plate (614) is a fourth angle, and the fourth angle is greater than the third angle.

8. The roof-mounted parking air conditioner according to claim 7, characterized in that: Within the projection plane of the horizontal plane, the first return air inlet (811) and the fifth return air inlet (815) are arranged symmetrically with respect to the third return air inlet (813), and the second return air inlet (812) and the fourth return air inlet (814) are arranged symmetrically with respect to the third return air inlet (813). The center line of the length of the third return air inlet (813) coincides with the center line perpendicular to the axis of the fan.

9. The roof-mounted parking air conditioner according to any one of claims 1-8, characterized in that: The heat exchanger (510) is an evaporator, and the heat exchanger (510) is a plate heat exchanger. The heat exchange plate surface of the plate heat exchanger is inclined to the horizontal plane, and the inclination angle is between 6° and 25°.

10. The roof-mounted parking air conditioner according to any one of claims 1-8, characterized in that: The housing (210) includes a chassis, and a volute (111) is also provided inside the housing (210). The fan (310) is located inside the volute (111) and is located downstream of the heat exchanger (510) along the airflow direction. The volute (111) is integrally formed with the chassis. An air outlet is provided on the chassis opposite to the fan (310) and faces the interior of the vehicle. The return air port (810) is also provided on the chassis and communicates with the interior of the vehicle.

11. The roof-mounted parking air conditioner according to claim 10, characterized in that: A water receiving structure is formed on the chassis and below the heat exchanger (510). The lower end of the water receiving structure is connected to a drain outlet (710). The drain outlet (710) is connected to an external drain pipe to discharge condensate from the shell (210).

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