JP2003048536A - Air conditioning system for rolling stock - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the noise of a propeller fan on outdoor machine side of an air conditioning system for rolling stock. SOLUTION: This air conditioning system for rolling stock comprises the propeller fan 1 set with a rotating shaft vertical, and a heat exchanger 3 arranged on the side of the propeller fan and constituted to pass the air driven by the propeller fan. A substantially truncated conical guide member 5a having a minor diameter-side end surface opposed to the downstream face of the boss part of the propeller fan 1 is provided on the downstream side of the propeller fan 1 concentrically to the propeller fan 1, and the outer diameter of the minor diameter-side end surface is set larger than the outer diameter of the boss part of the propeller fan 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a railcar air conditioner, and more particularly to an air conditioner outdoor unit installed on a roof of a railcar.

[0002]

2. Description of the Related Art An outdoor unit of an air conditioner for a railroad vehicle installed on the roof of a railroad vehicle has heat exchangers arranged on both sides of an outdoor propeller fan arranged with a rotating shaft in the vertical direction. Is common. Depending on the flowing direction of the air, there are both a mode in which the air discharged from the propeller fan enters the heat exchanger and a mode in which the air enters the propeller fan after passing through the heat exchanger. In both cases, heat exchangers are arranged on both sides so as to sandwich the propeller fan.By rotating the propeller fan, an air flow is generated, and outside air is sent to the heat exchanger to Heat is exchanged with the refrigerant flowing in the heat transfer tube.

In addition to this, the railroad vehicle air-conditioning system has an indoor unit room and a machine room. The indoor unit room contains a heat exchanger, a fan, etc. for the passenger compartment, and the machine room is in the machine room. Contains refrigeration cycle components such as compressors. A refrigeration cycle is constructed from them to air-condition the passenger compartment.

[0004]

In order to meet the required performance of a railroad vehicle air-conditioning system, heat exchangers are arranged in a plurality of rows, and as a result, the pressure loss on the air side becomes extremely large. . In such a state, the flow of air flowing out of the propeller fan becomes centrifugal rather than axial flow, and spreads radially. On the boss side downstream of the propeller fan, a backflow that enters between the blades of the propeller fan is generated, which increases noise.
Further, since it is used at an operating point where the pressure loss is high, the flow flowing out from the propeller fan has a large swirl speed associated with the rotation of the propeller fan. Therefore,
In the case where the air discharged from the propeller fan enters the heat exchanger, it flows in at a large angle with respect to the fins of the heat exchanger, so the pressure loss increases there and the cause of the air flow decrease. It was.

On the other hand, in the case where the air enters the propeller fan after passing through the heat exchanger, the air discharged from the propeller fan has a large centrifugal flow, and therefore the discharged air is installed laterally in the heat exchanger. It is easy to cause a short circuit to suck again from the intake port to. When a short circuit occurs, the heat exchanger sucks again the air whose temperature has risen after passing through the heat exchanger due to the cooling operation, for example, so that the performance as an air conditioner deteriorates.

In either case, the required air volume is achieved by increasing the rotational speed of the propeller fan to increase the air volume, but as a result, noise is also increased.

An object of the present invention is to reduce the blast noise of an air conditioning system for railway vehicles.

[0008]

As described above, the backflow generated near the boss portion on the downstream side of the propeller fan is one of the causes of noise. The inventors were able to reduce noise by preventing the occurrence of this backflow.

That is, the present invention for solving the above problems is
It has a propeller fan installed with its axis of rotation in the vertical direction, and a heat exchanger arranged on the side of the propeller fan and configured to allow the air driven by the propeller fan to pass through. In the air conditioning system for railway vehicles,
On the downstream side of the propeller fan, a guide member having a guide surface concentrically with the rotation axis of the propeller fan and having a shape that separates in the downstream direction from the rear surface of the propeller fan as being radially away from the rotation axis is provided. Characterize.

When the heat exchanger is arranged so that the air sucked into the propeller fan flows in, the guide member forms a part of a cover that covers the heat exchanger and the propeller fan. Can be formed.

Further, the guide member may have a truncated cone shape in which the end surface on the small diameter side is arranged to face the rear surface of the boss portion of the propeller fan. In this case, it is desirable that the radius of the end surface on the small diameter side be equal to or larger than the radius of the rear surface of the boss portion of the propeller fan.

As another cause of noise, in the case of a structure in which the air discharged from the propeller fan flows into the heat exchanger to perform heat exchange, the air discharged from the propeller fan with respect to the fins of the heat exchanger. The point of inflow is raised from an oblique direction. On the other hand, the inventors of the present invention, in the air flow path between the propeller fan and the heat exchanger, have a deflection guide plate that causes the flow direction of the air discharged from the propeller fan to approach the direction of the fins of the heat exchanger. Was set up. As a result, the flow direction of the air discharged from the propeller fan approaches the direction of the fins of the heat exchanger, and the air flows in from the direction close to the fins of the heat exchanger, thereby reducing noise. At the same time, the pressure loss could be reduced.

As another cause of noise, when the air that has passed through the heat exchanger is sucked into the propeller fan and exhausted upward from the propeller fan, the air exhausted upward from the propeller fan is not directly above. Since it becomes a centrifugal flow and is exhausted obliquely upward, it flows into the suction port of the heat exchanger, which may require an extra amount of air. The inventors
On the other hand, a partition plate extending in the vehicle front-rear direction is erected on the upper surface of the cover formed between the intake port and the exhaust port formed in the cover of the air conditioner to eliminate excess air volume, and as a result, reduce noise. I was able to.

[0014]

Embodiments of the present invention will be described below with reference to the drawings, but the present invention is not limited thereto. FIG. 1 shows an outdoor unit of a vehicle air conditioner according to a first embodiment of the present invention. The present embodiment is configured to include a compressor, an indoor unit, an outdoor unit, and piping and a control system for connecting them, but since the feature of the present invention lies in the outdoor unit part, description of other parts will be omitted. Omit it.

The outdoor unit shown in FIG. 1 has a housing 8 having a flat bottom surface, a motor 4 installed so that its rotation axis is perpendicular to the bottom surface, and a motor 4 coupled to the rotation axis. And the propeller fan 1 disposed above the motor 4 (on the side facing the bottom surface with the motor 4 sandwiched therebetween), and on both sides of the propeller fan 1 with the propeller fan 1 side inclined so as to be higher. Pair of heat exchangers 3, a fan ring 2a arranged so as to close the space between the propeller fan 1 and the heat exchanger 3, and a truncated cone shape arranged concentrically with the motor 4 around the motor 4. Guide member 5a, a deflection guide plate 6 provided upright on the bottom surface between the guide member 5a and the heat exchanger 3, and the upper surfaces of the heat exchanger 3 and the propeller fan 1 arranged so as to face the bottom surface. And a cover 7 for covering.

The cover 7 has an opening serving as an intake port 7a at a position facing the upper surface of the propeller fan 1 and an opening serving as an exhaust port 7b at a position facing the upper surface of the heat exchanger 3. .

The frustum-shaped guide member 5a has an opening formed on the end surface on the small diameter side to which the outer shape of the motor 4 is fitted, and the outer shape of the end surface on the small diameter side is smaller than the outer diameter of the boss portion of the propeller fan 1. It is large.

FIG. 2 is a schematic plan view seen from above with the cover 7 and the fan ring 2a of the outdoor unit of the vehicle air conditioner shown in FIG. 1 removed.

The propeller fan 1 is driven by a motor 4 to rotate and generate an air flow 9a. Air intake 7
The air flows into the outdoor unit of the vehicle air conditioner from a, passes through the propeller fan 1, changes its direction, and then passes through the outdoor heat exchangers 3 arranged on both sides of the propeller fan 1. When the air passes through the outdoor heat exchanger 3, the air exchanges heat with the refrigerant flowing in the heat transfer tube of the heat exchanger 3. The air whose temperature has changed due to heat exchange is exhausted to the outside of the machine through the exhaust port 7b.

In such an operating condition as the vehicle air conditioner, in the vehicle air conditioner of the present embodiment, the propeller fan 1 is arranged downstream from the propeller fan 1 with its shaft being concentric with the propeller fan 1 rotation shaft. Since the guide member 5a having a substantially frustoconical shape that opens to the right is installed, the backflow 11 on the boss side downstream of the propeller fan 1 is suppressed,
In addition, the centrifugally flowing flow is smoothly guided to the heat exchanger. As a result, the backflow on the boss side downstream of the propeller fan 1, which has been easily generated in the past, is suppressed and noise is reduced.

Since the end face on the small diameter side of the truncated cone-shaped member 5a is close to the trailing edge of the propeller fan 1, a backflow that tends to flow between the blades of the propeller fan 1 near the boss where backflow easily occurs is generated. Has the effect of suppressing further,
Since the distance from the propeller fan 1 gradually increases toward the blade tip side, it also has the effect of a diffuser that slows the flow and increases the static pressure by gently expanding the main flow passage. A slight increase in static pressure can be achieved. As a result, there is an effect of reducing noise by suppressing backflow, an increase in air volume by increasing static pressure, and further an effect of further reducing noise by reducing the number of revolutions of the propeller fan 1.

FIG. 3 shows a propeller fan 1 for a vehicle air conditioner.
The schematic side sectional view at the time of installing the truncated-cone-shaped guide member 5a and measuring a noise is shown. The shape of the guide member 5a is such that the propeller fan 1 side (end surface on the small diameter side) has a diameter substantially equal to the boss portion of the propeller fan 1, and from there, an angle is formed with respect to a plane orthogonal to the rotation axis of the propeller fan 1. A truncated cone having a slope that separates from the fan 1 at 30 °. The diameter of the guide member 5a farther from the propeller fan 1 (the end surface on the larger diameter side) is substantially the diameter of the propeller fan 1 (outer diameter of the blade tip).
Is the same as. The noise measurement was performed without the deflection guide plate 6.

FIG. 4 shows a comparison of noise spectra of the propeller fan 1 with and without the guide member 5a (measurement in the state of FIG. 3). As shown, the guide member 5
When a is present, the broadband noise due to turbulence is reduced over a wider frequency range than when the guide member 5a is not present.

Further, in the vehicle air conditioner of the present embodiment, the direction of the flow discharged from the propeller fan 1 between the propeller fan 1 and the heat exchanger 3 approaches the direction of the fins 3a of the heat exchanger 3. A deflection guide plate 6 for deflecting the light is provided. By this deflection guide plate 6, a flow 9a of air having a large swirling component discharged from the propeller fan 1
Can smoothly flow into the fins 3a of the heat exchanger 3, and the pressure loss that has increased there can be greatly reduced. As a result, the number of revolutions of the propeller fan 1 for obtaining the required air volume can be reduced, and the noise can be reduced.

In the present embodiment, the guide member 5a having a substantially truncated cone shape and the deflection guide plate 6 for changing the flow according to the fins 3a of the heat exchanger 3 are used in combination to reduce the noise. Although it is increased, even if the deflection guide plate 6 is applied alone, it has the effect of reducing noise.

In the present embodiment, a member having a truncated cone-shaped guide surface is provided as the guide member 5a. However, as the guide surface (the surface on the propeller fan 1 side) moves away from the axis of the propeller fan 1, the propeller fan 1 If the surface is away from the trailing edge of No. 1, it is not necessarily the truncated cone shape. However, at least the portion of the propeller fan 1 that faces the rear edge of the boss is a plane that is located close to the rear edge of the boss, and the diameter of the shoulder that transitions from this plane to the inclined surface is the rear edge of the boss. It is desirable that the diameter be equal to or larger than the diameter.

A second embodiment of the present invention will be described with reference to FIG. The present embodiment is different from the first embodiment in that the air flows in the opposite direction and that the air that has passed through the heat exchanger 3 flows into the propeller fan 1 and that the truncated cone-shaped guide member is provided. On the upper side of the propeller fan 1, that is, at a position facing the motor 4 with the propeller fan 1 interposed therebetween, the small-diameter side end face is concentrically installed with the propeller fan 1 facing, and instead of the deflection guide plate 6, The point is that a partition plate 10 is provided to partition the space between the intake port 7c and the exhaust port 7d on the upper surface of the cover 7. Since other configurations are the same as those in the first embodiment, the same reference numerals are given and the description thereof will be omitted. The opening of the cover above the heat exchanger 3 serves as an intake port 7c, and the opening of the cover formed in an annular shape diagonally above the propeller fan 1 serves as an exhaust port 7d. That is, the exhaust port 7b in the first embodiment becomes the intake port 7c in the present embodiment, and the gap left by the guide member 5b arranged in the intake port 7a in the first embodiment is the gap in the present embodiment. It is the exhaust port 7d.

In this embodiment, the propeller fan 1 is
It is mounted upside down from the first embodiment, and the direction of air flow is also opposite. That is, the air flow 9b generated by rotating the propeller fan 1 flows into the machine through the intake port 7c, first enters the heat exchanger 3 to perform heat exchange, and then is sucked into the propeller fan 1. Then, the gas is exhausted obliquely upward from the exhaust port 7d.

In the present embodiment, the portion of the cover that is located on the downstream side of the propeller fan 1 has the same shape as the truncated cone-shaped member 5a in the first embodiment, so that the first embodiment Similar to the configuration, the noise of the propeller fan 1 is reduced by the effect of suppressing the backflow on the downstream side and the boss side of the propeller fan 1 and increasing the static pressure.

Further, in the vehicle air conditioner configured to exhaust air upward as shown in FIG. 5, the flow out of the propeller fan 1 has a large centrifugal component. It is easy to generate a short circuit that flows to the mouth 7c side and sucks into the aircraft again. While the vehicle is traveling, the exhausted air is scavenged from the upper part of the vehicle air conditioner by the traveling wind, so the influence is relatively small, but the influence cannot be ignored when the vehicle is stopped.

In the present embodiment, in order to reduce the influence, a partition plate 10 extending in the vehicle front-rear direction is provided upright so as to partition between the intake port 7c and the exhaust port 7d above the cover 7. As a result, the flow of air exhausted from the propeller fan 1 and heading toward the intake port 7c hits the partition plate 10 before it reaches the upper part of the intake port 7c and changes its direction upward, so that the effect of the short circuit is reduced. . as a result,
The rotation speed of the propeller fan 1 for obtaining the required performance can be reduced, and the noise can be reduced. In addition, the partition plate 1 described above
Since 0 is mounted along the traveling direction of the vehicle, the noise generated by itself during traveling is much smaller than the sound of the propeller fan 1 and is at a level that does not pose a problem.

In FIG. 5, the partition plate 10 is installed so as to be inclined with respect to the bottom plate of the housing 8. However, it is not necessary to incline it and the partition plate 10 is perpendicular to the bottom plate of the housing 8. You may install like this.

Further, in the present embodiment, the effect of reducing noise is enhanced by using the truncated cone-shaped member 5b and the partition plate 10 for suppressing the short circuit together. It has the effect of making noise.

[0034]

As described above, according to the present invention, a favorable flow can be formed around the propeller fan of the outdoor unit for an air conditioner for a railway vehicle, so that the noise of the apparatus can be reduced. Furthermore, as a result of the reduction of pressure loss and the suppression of short circuits, the propeller fan speed can be reduced more than before, and further noise reduction can be expected.

[Brief description of drawings]

FIG. 1 is a schematic side cross-sectional view of a vehicle air conditioner outdoor unit showing a first embodiment of the present invention.

FIG. 2 is a schematic plan view of the vehicle air conditioner outdoor unit shown in FIG.

FIG. 3 is a schematic side sectional view illustrating a test situation in which a truncated cone-shaped member is installed in a propeller fan for a vehicle air conditioner.

FIG. 4 is a graph showing a comparison of noise levels when a truncated cone-shaped guide member is provided and when a truncated cone-shaped guide member is not provided.

FIG. 5 is a schematic side sectional view of a vehicle air conditioner outdoor unit showing a second embodiment of the present invention.

[Explanation of symbols]

1 propeller fan 2 fan ring 3 heat exchanger 4 motor 5 Frustum-shaped guide member 6 Deflection guide plate 7 cover 8 housing 9 Air flow 10 partition boards

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ Identification code FI Theme Coat (reference) F24F 5/00 F24F 5/00 Q (72) Inventor Makoto Otani 502, Kandachi-cho, Tsuchiura-shi, Ibaraki Japan Co., Ltd. Inside the Tate Seisakusho Laboratories (72) Hiroaki Matsushima, 502 Kintatecho, Tsuchiura-shi, Ibaraki Prefecture Hitate Co., Ltd. Inside the R & D Laboratories (72) Kazuya Matsuo, 502 Kintate-cho, Tsuchiura-shi, Ibaraki Nitate Mills Co., Ltd. Inside the laboratory (72) Haruo Hirakawa 794 Higashitoyo Higashitoyo, Shimomatsu, Yamaguchi Prefecture Inside the Kasado Plant, Hiritsu Manufacturing Co., Ltd. (72) Yoshichika Fukushima 794 Higashitoyoi Higashitoyo, Shimomatsu City, Yamaguchi Prefecture Inside the Kasado Plant, Hiritsu Manufacturing Co., Ltd. Term (reference) 3L011 BS01

Claims (6)

[Claims] 1. A propeller fan installed with its rotation axis oriented in a vertical direction, and a heat exchanger arranged laterally of the propeller fan and configured to allow air driven by the propeller fan to pass therethrough. In an air conditioner for a railroad vehicle comprising: a propeller fan, on the downstream side, concentrically with a rotation axis of the propeller fan, and a shape that is separated from a rear surface of the propeller fan in a downstream direction as being radially away from the rotation axis. An air conditioner for a railroad vehicle, characterized in that it is provided with a guide member having a guide surface. 2. The air conditioner for a railway vehicle according to claim 1, wherein a cover is provided above the propeller fan and the heat exchanger, and the heat exchanger prevents the air taken in by the propeller fan. An air conditioner for a railway vehicle, which is arranged so as to flow in and the guide member forms a part of the cover. 3. The air conditioner for a railway vehicle according to claim 1, wherein the guide member has a truncated cone shape in which an end surface on the small diameter side is arranged to face a rear surface of a boss portion of the propeller fan. An air conditioning system for railway vehicles, which is characterized in that 4. The railcar air conditioner according to claim 3, wherein the radius of the end surface on the small diameter side is equal to or larger than the radius of the rear surface of the boss portion of the propeller fan. 5. A propeller fan installed with its rotation axis oriented in a vertical direction, and a heat exchanger arranged laterally of the propeller fan and configured to allow air driven by the propeller fan to pass therethrough. In a railcar air conditioning system comprising, the heat exchanger is arranged so that the air discharged from the propeller fan flows in, and in the air flow path between the propeller fan and the heat exchanger, An air conditioner for a railway vehicle, comprising: a deflection guide plate that makes a flow direction of air discharged from a propeller fan closer to a direction of the fins of the heat exchanger. 6. A propeller fan installed with its rotation axis oriented in the vertical direction, and a heat exchanger arranged laterally of the propeller fan and configured so that air drawn into the propeller fan flows in. A railcar having a cover provided above the propeller fan and the heat exchanger, having an intake port above the heat exchanger and an exhaust port above the propeller fan, respectively. In the air conditioner, a partition plate extending in the vehicle front-rear direction is provided upright on the upper surface of the cover between the intake port and the exhaust port, the air conditioner for a railway vehicle.