JPH0413607B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an air conditioner that blows cooling air cooled by a cooling unit to necessary locations through a duct.

(Problems with the prior art) Conventionally, air conditioners that locally condition air in large spaces such as factories, etc., have been known to provide cooling air cooled by a cooling unit through ducts, such as when people are present. It was meant to guide wind to the location.

In this case, the cold air blown into the surrounding warm air from the air outlet provided at the tip of the duct diffuses with distance, the wind speed and temperature difference decrease, and the cooling effect decreases. Therefore, conventionally, in order to increase the cooling effect, it was necessary to increase the cooling capacity of the cooling unit. However, in this case, there were problems such as an increase in the size of the cooling unit due to the increase in cooling capacity and an increase in manufacturing costs.

(Objective of the Invention) Therefore, an object of the present invention is to prevent the spread of cold air by making the duct of an air conditioner a double structure, thereby improving the cooling performance without increasing the cooling capacity of the cooling unit. .

(Example) Hereinafter, the present invention will be specifically described based on an example shown in the drawings.

FIG. 1 is a schematic diagram showing the overall configuration of an air conditioner according to a first embodiment of the present invention. The internal configuration of the air conditioner 1 includes a refrigerant circuit consisting of a compressor 2, a condenser 3, an expansion valve (not shown), and an evaporator 4, and a condenser 3.
It consists of a condenser fan 5 for air cooling, an air conditioning fan 6 for blowing cold air cooled by the evaporator 4, and a double-shaft motor 7 for driving the fans 5 and 6. This configuration corresponds to the cooling unit in the present invention. That is, in this example, a vapor compression refrigeration system is adopted for the cooling unit. Other methods include an absorption refrigeration method that uses an absorbent and heating means, a steam injection refrigeration method that injects refrigerant vapor into the ejector at high speed, and the jet stream lowers the pressure inside the evaporator. There are electronic refrigeration systems that utilize the Peltier effect. In short, any method may be used as long as it can cool the air-conditioned area, and the method is not limited thereto.

In the configuration of the air conditioner described above, the evaporator 4 is housed in the evaporator case 8.
A drain tank 9 is installed in the space below. Therefore, the condensed water of the evaporator 4 is discharged from the drain port 8a opened at the bottom of the evaporator case 8, and is stored in the drain tank 9.

A suction port 10 for ambient air to cool the condenser 3 is provided on the back of the air conditioner main body 1, and an outlet 11 for air that has become warm after cooling the condenser 3 is provided on the top surface of the air conditioner main body 1. is set up. Furthermore, an air intake port 12 for cooling is provided on the front surface of the air conditioner main body 1, and the air taken in from this air intake port 12 is cooled by the evaporator 4 and then connected to the evaporator case 8. It is designed to be fed into a lead-out duct 13.

Further, a duct 15 for blowing the cooling air is attached to an upper inclined portion of the front surface of the air conditioner main body 1 by an attachment member 16. This duct 15 has a cylindrical outer tube 15a and a cylindrical inner tube 15.
The inner cylinder 15b is connected to the outlet duct 13 at an appropriate portion. Therefore, only the air cooled by the evaporator 4 is blown into the main flow passage 17 inside the inner cylinder 15b.

On the other hand, a subflow passage 18 is formed between the outer cylinder 15a and the inner cylinder 15b of the duct 15. This sub-flow passage 18 communicates with the air conditioner internal space 1a which is isolated from the outlet duct 13 and the evaporator case 8. Air surrounding the air conditioner main body 1 is introduced from the suction port 19 by a centrifugal blower fan 20. Reference numeral 21 is a motor for driving the fan 20, and a motor smaller than the motor 7 is used. This motor 21 is the motor 7
An electric circuit is configured to operate simultaneously with the operation of the .

Note that filters are attached to the suction ports 10, 12, and 19 to prevent dust and the like from entering.

Next, the structure of the duct 15 will be explained in detail. In the duct 15, both the outer cylinder 15a and the inner cylinder 15b are cylindrical, and the contact area with the surroundings is the smallest compared to other shapes, so the reach of air blown from the duct tip 15c is the highest compared to other shapes. big. The outer cylinder 15a and the inner cylinder 15b are made of a resin such as vinyl chloride having heat insulating properties, and are formed into a bellows shape that is flexible enough to be bent in vertical and horizontal directions. In this case, the length of the duct 15 is actually longer than that shown in FIG. 1, and the length of the duct 15 is actually longer than that shown in FIG. A plurality of ring-shaped holding members 22 are arranged in the subflow passage 18 at appropriate intervals so that the center points of the outer cylinder 15a and the inner cylinder 15b coincide. This holding member 22 has a resin honeycomb structure, and the secondary flow passage 1
The air passing through the chamber 8 can be ventilated and can be rectified. The holding member 22 may be attached to either the inner tube 15b or the outer tube 15a with an adhesive, or to both with screws or the like.

In addition to the above, the holding member may be provided with four protrusions 23 at appropriate intervals within the side flow passage 18, as shown in FIG. This protrusion 23 is provided by integral molding on the inner cylinder 15b or the outer cylinder 15a, or is installed separately from both, and is attached from the outer cylinder 15a side with a bolt or the like.
In this example, there are four protrusions 23, but two or more protrusions 23 will have the same effect.

Next, the operation of the first embodiment with the above configuration will be explained.

When the operating switch (not shown) provided on the front panel of the air conditioner body 1 is switched to cold air mode, the drive motor of the compressor 2 is activated, the refrigerant is compressed to high temperature and pressure by the compressor 2, and is compressed by the condenser 3. A refrigeration cycle is formed in which the refrigerant is condensed to become a liquid refrigerant, rapidly reduced in pressure by an expansion valve (not shown), and evaporated by an evaporator 4. Further, at the same time as the drive motor of the compressor 2 is operated, the air blowing motors 7 and 21 are also operated.

Therefore, the ambient air sucked in through the suction port 12 by the rotation of the fan 6 is cooled by the evaporator 4 and sent into the inner cylinder 15b through the outlet duct 13. On the other hand, due to the rotation of the fan 20 driven by the motor 21, the ambient air sucked in from the suction port 19 passes through the space 1a and enters the side flow path 1.
Sent into 8.

As a result of the above, among the air outlets 15c provided at the tip of the duct 15, the air outlet 17a of the main flow passage 17
Cold air flows from the outlet 18a of the side flow passage 18.
Air is blown out from the main passage 17 so as to envelop the cold air from the main flow passage 17, and whose temperature is approximately the same as that of the surrounding air.

In this case, the amount of air sent into the side flow passage 18 by the fan 20 is smaller than the amount of air sent into the main flow passage 17 by the fan 6.
That is, the flow velocity of the air flowing through the subflow passage 18 is smaller than the flow velocity of the air flowing through the main flow passage 17.

Therefore, since the flow velocity of the air blown out from the subflow passage 18 is low, the viscous force with the surrounding air can be suppressed to a low level, and the diffusion attenuation of the cold air blown out from the main flow passage 17 is prevented, and the temperature of the cold air is reduced. This will extend the reach of the cold air.

Here, the reach distance of the cold air is determined by the flow velocity ratio of the main stream and the side stream, and the flow velocity ratio of the main stream passage 17 and the side stream passage 18.

Therefore, the present inventors conducted detailed experiments regarding these relationships. The following was revealed.

FIG. 4 is a schematic diagram showing the velocity and temperature of air blown out from the duct of the present invention.

The symbols shown in FIG. 4 are each defined as follows.

Uo: Mainstream wind speed, Us: Sidestream wind speed, Temperature at the center of the mainstream jet at the point, t∞: Ambient air temperature near the point X apart from the tip of the duct 15, Δto=t∞−to: Mainstream outlet temperature difference, Δtx=t∞−
tx: Mainstream temperature difference, Do: Diameter of inner cylinder 15b, Ds:
Diameter of outer cylinder 15a Furthermore, the following is defined by the above symbols.

Ux/Uo: Speed attainment rate, Δtx/Δto: Temperature attainment rate σ=Us/Uo: Speed ratio, γ=Ds/Do: Diameter ratio In addition, in a conventional duct without side flow, the wind speed at the tip of the duct 15 and The temperature is Uo, respectively.
If to is the wind speed and temperature at a point X apart from the tip of the duct 15 are Uxo and txo, respectively.
The speed attainment rate of conventional ducts is expressed as Uxo/Uo,
The temperature attainment rate is (t∞−txo)/(t∞−to)=Δtxo/Δto Therefore, when comparing the attainment rates of the conventional and this example, the speed attainment improvement rate α and temperature attainment improvement rate β are as follows. It is shown as follows.

α=Ux/Uo/Uxo/Uo=Ux/Uxo β=Δtx/Δto/Δtxo/Δto=Δtx/Δtxo Generally, the temperature attainment rate and the speed attainment rate are in a proportional relationship, so from the above equation, α≈β.

Here, the inventors have determined that the velocity attainment rate Ux/Uo is obtained by changing the speed ratio Us/Uo of the main stream and the side stream and the diameter ratio Ds/Do of the inner cylinder 15b and the outer cylinder 15a.
and changes in temperature attainment rate Δtx/Δto were investigated. Figures 5 and 6 show the measurement results, and the horizontal axes in Figures 5 and 6 are the speed ratio Us/Uo and the aperture ratio, respectively.
Indicates Ds/Do. Further, the vertical axes in FIGS. 5 and 6 both indicate the speed attainment improvement rate α and the temperature attainment improvement rate β. Here, the air volume is the total air volume that is the sum of the mainstream air volume and the side flow air volume, and the experiment was conducted with the distance X from the tip of the duct 15 being 8 times the diameter Do of the inner cylinder 15b. Almost the same result can be obtained if the length of X is approximately five times or more the diameter Do of the inner cylinder 15b. In addition, in the experiment shown in Figure 5, the aperture ratio γ = 1.4, and in the experiment shown in Figure 6, the speed ratio σ =
It was set to 0.3.

In FIGS. 5 and 6, the case where the speed ratio σ=Us/Uo is 0 and 1 and the case where the diameter ratio γ=Ds/Do is 1 shows the case of a conventional duct structure without a subflow passage.

As can be clearly seen from Figures 5 and 6, the following has become clear.

That is, the speed ratio σ is 0.15 to 0.6, and the aperture ratio γ is
In the range of 1.25 to 2.0, the speed and temperature attainment rates are improved by more than 10% compared to the conventional one without the side flow passage 18. Moreover, since there is no need to cool the side stream side, there is a further power saving effect, and the highest efficiency point (σ = 0.3, γ =
1.4), it was found that the same ultimate wind speed and cold air temperature could be obtained with 50% of the conventional cooling capacity.

Therefore, in the first embodiment, in order to obtain the maximum cooling effect, the duct 15 is configured such that the diameter ratio γ of the inner cylinder 15b and the outer cylinder 15a is γ=1.4.
The drive motor 21 of the fan 20 may be selected so that the speed ratio σ becomes σ=0.3.

Further, a variable resistor, a transistor, or the like may be connected to the drive electric circuit of the motor 21 so that the motor rotation speed can be made variable so that any speed and temperature attainment rate can be obtained according to preference.

Next, a second embodiment of the present invention will be described. In this example, as shown in FIG. 7, a main flow passage 17 and a sub-flow passage 18 are formed midway inside the duct 15, and cold air is introduced into the sub-flow passage 18 by a fan 6. Here, the main flow passage 17 and the side flow passage 1
The end portion 15d of the inner cylinder 15b that partitions the inner cylinder 15b is widened in a tapered shape, increasing the ventilation resistance of the air flowing into the side flow passage 18, and making the speed of the air flow in the side flow passage 18 slower than that in the main flow passage 17. fulfill the role of Note that the other configurations are the same as those in the first embodiment, so explanations will be omitted.

In the first example, ambient air is introduced into the side stream side, but it is possible to obtain the same velocity attainment rate and temperature attainment rate even if cold air is introduced into the side stream side as in this example. The inventors have confirmed this. In other words, the velocity attainment rate and the temperature attainment rate are determined not by the temperature of the air on the side stream side but by the flow velocity of the air flowing through the side flow path 18.

However, in this example, since the cold air is also caused to flow through the sub-flow passage 18, the cooling capacity of the air conditioner is required to correspond to that amount compared to the first example. However, Figures 5 and 6
At the highest efficiency point (σ = 0.3, γ = 1.4) shown in the figure, the same ultimate wind speed and cold air temperature can be obtained with approximately 70% of the cooling capacity compared to the conventional example without side flow passages.

Furthermore, when compared with the first embodiment, this embodiment has the advantage that the fan 20 and motor 21 dedicated to the side stream can be eliminated, and the structure can be simplified because the inner cylinder 15b can be disposed from the middle.

Next, a third embodiment of the present invention will be described. In this example, an inner cylinder is provided only near the duct outlet, and the inside of the duct is divided into a main stream and a side stream. Furthermore, this example is characterized in that by changing the opening area of the side flow passage, the side flow wind speed is changed, thereby making it possible to select the arrival rate.

8 to 10 show the third embodiment, in which an inner cylinder 40b is held inside an outer cylinder 40a near an outlet 15c of a duct 15 by a holding member 41.
a, and a main flow passage 50 and a side flow passage 51 are formed. Four holding members 41 are provided in the circumferential direction as in FIG. 3, and one end is attached to the inner cylinder 40b.
Further, the other end is fixed to the outer cylinder 40a with screws or the like. In addition, the subflow passage 5 of the inner cylinder 40b
A ring-shaped fixed control plate 42 is attached near the first inlet. This fixed control plate 42 is a perforated plate, and has a plurality of ventilation holes 42a as shown in FIG.

On the other hand, a ring-shaped movable control plate 43 is provided in the sub-flow passage 51 on the duct tip end side of the fixed control plate 42 so as to be rotatable in the circumferential direction of the duct 15 . That is, the movable control plate 43 is a perforated plate similar to the fixed control plate 42, and is provided with ventilation holes 43a as shown in FIGS. 9 and 10. This movable control plate 43 is provided with an operation knob 43b protruding from the outer cylinder 40a, and the knob 43b is manually operated so as to draw an arc along a long groove 40a-1 provided in the outer cylinder 40a. Ru.

FIG. 9 shows a state in which the side of the secondary flow passage 51 is closed. When the knob 43b is operated in the direction of arrow A from the state shown in FIG. 9, the ventilation hole 4
2a and 43a begin to overlap, and wind is introduced into the subflow passage 51. FIG. 10 shows ventilation holes 42a and 43.
a indicates a completely overlapping state, and the maximum amount of air is introduced into the subflow passage 51.

In this way, by operating the knob 43b, the amount of air introduced into the subflow passage 51 is adjusted, and therefore the wind speed within the subflow passage 51 is changed, and the speed attainment rate and temperature attainment rate are adjusted. becomes possible.

Note that the opening area of the fixed control plate 42 and the movable control plate 43 with ventilation 42a, 43a is the same as that of the inner cylinder 40.
b. It can be provided as appropriate so that an appropriate arrival rate can be selected depending on the size of the outer cylinder 40a.

The shape of the duct in the air conditioner of the present invention is most preferably cylindrical as shown in the above embodiments, but it is not limited to the cylindrical shape and can be modified in various ways, such as having a rectangular cross section or an elliptical shape. be.

(Effects of the Invention) As described above, the present invention divides the inside of a duct that blows cooling air cooled by a cooling unit to necessary locations into a main flow passage and a subflow passage by a partition member. In addition, since the flow velocity of the air in the side flow passage is slower than the flow velocity of the air in the main flow passage, the cold air blown into the surrounding air from the main flow passage side flows around it at a slower flow velocity than that of the air blown out from the side flow passage. By blowing out the air while being covered with air, the diffusion into the surrounding air is suppressed, which has the excellent effect of extending the reach of the cold air while maintaining a cool temperature, and increasing the feeling of cooling. .

Further, from the above, the present invention can improve the cooling effect of the air conditioner without increasing the cooling capacity of the cooling unit, and therefore has the effect of making it possible to save energy without impairing the cooling effect. .

[Brief explanation of drawings]

The drawings all show embodiments of the present invention, and FIG. 1 is a configuration diagram of an air conditioner according to the first embodiment, FIGS. 2 and 3 are structural diagrams showing the duct structure of the first embodiment, and FIG. Principle diagrams of the duct of the air conditioner of the present invention, Figures 5 and 6
The figures are characteristic diagrams showing temperature attainment improvement rate and speed attainment improvement rate with respect to speed ratio and aperture ratio, respectively. Fig. 7 is a configuration diagram of an air conditioner showing a second embodiment of the present invention. Fig. 8 is a diagram showing the configuration of an air conditioner according to the second embodiment of the present invention. A sectional view showing a third embodiment of
9 and 10 are sectional views taken along the line BB in FIG. 8. 1... Air conditioner body, 2... Compressor, 3... Condenser,
4...Evaporator, 5...Condenser cooling fan, 6...Cooling air blower fan, 15...Duct, 15a...Outer cylinder, 15
b...Inner cylinder, 17...Mainstream passage, 18...Substream passage, 2
0...Ambient air blowing fan to the side flow passage, 15d...
Lump-shaped inner cylinder end, 23... Holding member, 42... Fixed control plate, 43... Movable control plate, 42
a, 43a...Vent hole, 40a...Outer cylinder, 40b...Inner cylinder, 50...Main flow passage, 51...Side flow passage.

Claims (1)

[Claims] 1. Inhale ambient air, cool the inhaled air,
In an air conditioner comprising a cooling unit configured to send out cooling air, and a duct provided protruding from the cooling unit to blow the cooling air to necessary locations, at least one of the ducts is provided. Inside the outlet, there is a main flow passage through which the cooling air passes, and a subflow passage is formed around the outer periphery of the main flow passage, and a variable flow rate is formed to make the flow velocity of the air in the subflow passage slower than the flow velocity of the main flow passage. An air conditioner characterized by comprising means. 2 Of the duct, at least the outlet portion thereof is composed of a cylindrical outer cylinder and an inner cylinder provided inside the outer cylinder, the main flow passage is formed inside the inner cylinder, and the secondary flow passage is formed inside the inner cylinder. 2. The air conditioner according to claim 1, wherein a passage is formed between the inner cylinder and the outer cylinder. 3 The diameter of the outer cylinder is Ds, and the diameter of the inner cylinder is Do.
The air conditioner according to claim 2, wherein the aperture ratio is set to be 1.25≦Ds/Do≦2.0. 4. Claims 1, 2, and 3, wherein the flow rate variable means is a fan provided in the cooling unit so as to introduce ambient air into the subflow passage. Air conditioner described in any of the paragraphs. 5. The flow rate variable means according to any one of claims 1, 2, and 3, wherein the upstream opening end of the inner cylinder is expanded toward the upstream side. Air conditioner. 6. Claim 6, characterized in that the flow rate variable means is two perforated plates provided between the inner tube and the outer tube and controlling the amount of air flowing into the auxiliary flow passage. The air conditioner according to any one of item 1, item 2, and item 3.