JP7744021B2 - Compressed air dehumidifier and compressed air dehumidifier unit - Google Patents

Description

The present invention relates to a compressed air dehumidifier and compressed air dehumidifier unit in which a heat exchanger is provided in two stages, a first heat exchanger section and a second heat exchanger section, inside the dehumidifier housing so as to dehumidify primary-side compressed air introduced from a compressed air unit through heat exchange and discharge the dehumidified secondary-side compressed air to pneumatic equipment; the first heat exchanger section is provided by arranging a pre-cooling flow path for the primary-side compressed air and a reheating flow path for the secondary-side compressed air so that the first heat exchanger section pre-cools the primary-side compressed air and reheats the secondary-side compressed air so that the pre-cooling flow path for the primary-side compressed air and the reheating flow path for the secondary-side compressed air intersect; and the second heat exchanger section is provided to cool the compressed air pre-cooled in the first heat exchanger section with a cooling medium, thereby causing condensation and dehumidifying the air.

A conventional compressed air dehumidifier proposed by the present applicant includes a dehumidifier main body having an inlet for introducing compressed air, a cooling unit that cools the compressed air introduced through the inlet and condenses the moisture in the compressed air to dehumidify it, and an outlet for discharging the compressed air dehumidified by the cooling unit; an evaporator located in the cooling unit inside the dehumidifier main body, and a cooling circuit having a compressor, condenser, and expansion valve located outside the dehumidifier main body, and circulating a refrigerant through the evaporator, compressor, condenser, and expansion valve in that order; and a reheater that heats the compressed air discharged from the outlet using heat from the cooling circuit (see Patent Document 1).

The present applicant has also proposed a conventional vertically mounted compressed air dehumidifier, which includes a heat exchanger arranged in two stages, a first heat exchanger section and a second heat exchanger section, arranged side by side vertically and housed within a cylindrical outer wall body. The first chamber 26 is located below the two heat exchanger sections and is a small chamber into which the air outlet of the second heat exchanger section and the inlet of the reheating flow path open, with a drain section at its lower end; a second chamber is located above the two heat exchanger sections and retains compressed air just before it is discharged; an extended air vent section that extends downward so that the air outlet of the second heat exchanger section is located below the inlet of the reheating flow path; and a demister located at the lower end of the extended air vent section and through which compressed air passes (see Patent Document 2).

Furthermore, the present applicant has proposed a compressed air dehumidifier equipped with a conventional temperature sensor. The dehumidifier includes a dehumidifier main body having an inlet for introducing compressed air, a cooling section that cools the introduced compressed air and condenses the moisture in the compressed air to dehumidify it, and an outlet port for discharging the dehumidified compressed air; a compressor, a condenser, an expansion valve, and an evaporator located in the cooling section of the dehumidifier main body, and a cooling circuit having a refrigerant circulation pipe that circulates refrigerant through the compressor, condenser, expansion valve, and evaporator in that order; in which a temperature sensor is attached to the refrigerant circulation pipe on the refrigerant outlet side of the evaporator, where it comes into contact with the compressed air after passing through the evaporator (see Patent Document 3).

Furthermore, the present applicant has proposed a compressed air dehumidifier capable of maintaining the required dew point. The dehumidifier includes a dehumidifier main body having an inlet for introducing compressed air, a cooling unit that cools the introduced compressed air and condenses the moisture in the compressed air to dehumidify it, and an outlet for discharging the dehumidified compressed air; a compressor, a condenser, an expansion valve, and an evaporator located in the cooling unit of the dehumidifier main body, and a cooling circuit that circulates refrigerant through the compressor, condenser, expansion valve, and evaporator in that order. The controller stops operation of the compressor if the refrigerant temperature falls below a predetermined temperature while the compressor is operating, based on the refrigerant temperature at the refrigerant outlet side of the evaporator, and resumes operation of the compressor if the compressed air temperature exceeds a predetermined temperature while the compressor is stopped, based on the temperature of the compressed air passing through the evaporator (see Patent Document 4).

JP 2011-005374 A (page 1) JP 2017-127801 A (page 1) JP 2016-052610 A (page 1) JP 2016-052611 A (page 1)

The problem to be solved with regard to compressed air dehumidifiers and compressed air dehumidifier units is that, in vertically elongated compressed air dehumidifiers that are designed to dehumidify compressed air by cooling it with a cooling medium to cause condensation, there have been no proposals regarding the appropriate placement of a temperature sensor that can detect (monitor) the dew point temperature so as to appropriately adjust and control the cooling load of the cooling medium. Prior art (see Patent Documents 3 and 4) proposes attaching a temperature sensor to the refrigerant flow pipe on the refrigerant outlet side of the evaporator to measure the refrigerant temperature and thereby control the cooling load, but because it does not directly measure the dew point temperature, it is difficult to improve accuracy.

The object of the present invention is to provide a vertically elongated compressed air dehumidifier and compressed air dehumidifier unit in which a temperature sensor capable of detecting dew point temperature is disposed in an appropriate position.

In order to achieve the above object, the present invention has the following configuration.
According to one aspect of the compressed air dehumidifier of the present invention, a heat exchanger is provided in two stages, a first heat exchanger unit and a second heat exchanger unit, inside a dehumidifier housing so as to dehumidify primary-side compressed air introduced from a compressed air device by heat exchange and discharge the dehumidified secondary-side compressed air to pneumatic equipment, the first heat exchanger unit is provided by arranging a pre-cooling flow path for the primary-side compressed air and a reheating flow path for the secondary-side compressed air so as to pre-cool the primary-side compressed air and reheat the secondary-side compressed air so as to intersect, and the second heat exchanger unit is provided to cool the compressed air pre-cooled in the first heat exchanger unit with a cooling medium to cause condensation and dehumidify the compressed air, and a temperature sensor having a sensing unit disposed adjacent to the first chamber at the position of the air outlet of the second heat exchanger unit.

Furthermore, one embodiment of the compressed air dehumidifier according to the present invention comprises an extended air vent section extending downward so that the air outlet of the second heat exchanger section is located below the inlet of the reheat flow path, and a demister disposed at the lower end of the extended air vent section and separating moisture from the compressed air by passing the compressed air discharged at the air outlet of the second heat exchanger section through the demister, and the sensing portion at the tip of the temperature sensor is inserted inside the demister so as to come into contact with components that make up the demister.

Furthermore, according to one embodiment of the compressed air dehumidifier of the present invention, the temperature sensor can be attached by fixing the base of the temperature sensor to a portion of the dehumidifier housing that forms the first small chamber.

Furthermore, according to one embodiment of the compressed air dehumidifier of the present invention, the cooling medium is a refrigerant of a refrigeration cycle device including a compressor, a condenser, an expansion valve, and an evaporator, and the evaporator is a component of the second heat exchanger unit.

Furthermore, one embodiment of the compressed air dehumidifier according to the present invention can be characterized by including a control device that controls the operation of the refrigeration cycle device based on information detected by the temperature sensor.

Furthermore, according to one embodiment of the compressed air dehumidifier unit of the present invention, the compressed air dehumidifier and the refrigeration cycle device are housed inside a casing, and the dehumidifier housing has a compressed air inlet through which compressed air is introduced and a compressed air outlet through which dehumidified compressed air is discharged. The compressed air outlet and outlet piping extending from the compressed air outlet are disposed at an upper portion inside the casing, the condenser of the refrigeration cycle device is disposed below the compressed air outlet, and a cooling fan of the condenser is disposed so as to blow air toward the inside of the casing, and exhaust air generated when air is heated by the blowing of the cooling fan as it passes through a heat exchanger of the condenser is blown through the compressed air outlet and The exhaust port in the casing for the exhaust air is provided at the top of the casing so that the exhaust air passes through the space in which the outlet piping is arranged, the compressed air inlet and the inlet piping extending from the compressed air inlet are arranged at the top of the interior of the casing, the condenser of the refrigeration cycle device is arranged below the compressed air inlet and the cooling fan of the condenser is arranged to blow air toward the interior of the casing, and the exhaust port in the casing for the exhaust air is provided at the top of the casing so that the exhaust air generated when the air is heated by the blowing of the cooling fan as it passes through the heat exchanger of the condenser is exhausted through the space in which the compressed air inlet and the inlet piping are arranged.

The compressed air dehumidifier and compressed air dehumidifier unit of the present invention have the particularly advantageous effect of allowing a temperature sensor capable of detecting the dew point temperature to be positioned in an appropriate position when the compressed air dehumidifier is installed in a vertically elongated configuration.

1 is a schematic vertical cross-sectional view seen from the side, showing an example of a compressed air dehumidifier unit according to the present invention. FIG. 2 is a schematic front view of the embodiment of FIG. 1 as viewed from the front side. 2 is a schematic vertical cross-sectional view of the embodiment of FIG. 1 as seen from the rear side. FIG. 1 is an explanatory diagram showing an example of a compressed air dehumidifier system according to the present invention, and schematically illustrating a longitudinal section and a refrigeration cycle of a compressed air dehumidifier. 1 is a vertical cross-sectional view showing an example of a compressed air dehumidifier according to the present invention.

An example of a compressed air dehumidifier unit according to the present invention will be described in detail below with reference to the accompanying drawings (Figures 1 to 5).

The compressed air dehumidifier unit of the present invention comprises a refrigeration cycle device 10 including a compressor 11, a condenser 12, an expansion valve 14, and an evaporator 15; a dehumidifier housing 21 serving as a pressure vessel having a compressed air inlet 22 through which compressed air is introduced and a compressed air outlet 24 through which dehumidified compressed air is discharged; and a compressed air dehumidifier 20 including an evaporator 15 of the refrigeration cycle device 10 installed inside the dehumidifier housing 21 so as to cool the compressed air introduced into the dehumidifier housing 21 and dehumidify the moisture in the compressed air by condensing it, all housed inside a casing 50. In other words, the evaporator 15 of the refrigeration cycle device 10 is built into the compressed air dehumidifier 20, and the compressor 11, condenser 12, and expansion valve 14 of the refrigeration cycle device 10 are installed outside the compressed air dehumidifier 20 and housed inside the casing 50.

In addition, in the compressed air dehumidifier unit according to the present invention, the compressed air outlet 24 and the outlet piping 25 extending from the compressed air outlet 24 are positioned at the top of the interior of the casing 50, the condenser 12 of the refrigeration cycle device 10 is positioned below the compressed air outlet 24, and the cooling fan 13 of the condenser 12 is positioned so as to blow air (outside air) toward the interior of the casing 50.

In the compressed air dehumidifier unit of the present invention, an exhaust port 51 in the exhaust casing 50 is provided at the top of the casing 50 so that the exhaust air generated when the air is heated as it passes through the heat exchanger section 12a of the condenser 12 by the air blown by the cooling fan 13 is exhausted through the space in which the compressed air outlet 24 and outlet piping 25 are arranged.

The compressed air dehumidifier unit of the present invention has the particularly advantageous effect of being able to appropriately utilize the exhaust heat of the condenser 12 of the refrigeration cycle device 10 to reheat the dehumidified compressed air discharged from the compressed air outlet 24 of the compressed air dehumidifier 20. That is, the dehumidified compressed air discharged from the compressed air outlet 24 of the compressed air dehumidifier 20 is cooled when dehumidified by the cooling action of the evaporator 15, but can be reheated by directing the exhaust air heated by the exhaust heat of the condenser 12 toward the compressed air outlet 24 and outlet piping 25. This allows the compressed air to be reheated and compressed air of the desired temperature to be discharged and supplied as product air, thereby making effective use of the exhaust heat of the condenser 12 and achieving energy savings. For example, compressed air cooled by a refrigerant in a heat exchanger such as the second heat exchanger section 40 described below and discharged has a relative humidity of 100% at the air outlet 47. Reheating the air through the reheating flow path 32 reduces the relative humidity, but to prevent re-condensation, it is desirable to reheat the air to approximately the outside temperature. According to the present invention, by utilizing the exhaust heat from the condenser 12 of the refrigeration cycle device 10 as described above, reheating can be performed effectively to prevent re-condensation.

In addition, in this embodiment, the compressed air dehumidifier 20 is installed vertically inside the casing 50. In other words, the vertically-installed compressed air dehumidifier 20, which is long vertically, is stored upright inside the vertically-shaped casing 50. The casing 50 in this embodiment has a box-like shape that is a vertically-long rectangular parallelepiped.

This configuration allows the exhaust air from the condenser 12 to flow smoothly, reducing the installation floor space and enabling a compact installation. In other words, the vertical installation configuration allows for effective use of the installation space, and the heated air creates an ascending air current, allowing the exhaust air from the condenser 12 to flow smoothly. This allows the exhaust air from the condenser 12 to be smoothly directed toward the compressed air outlet 24 and outlet piping 25, efficiently heating (reheating) the dehumidified compressed air discharged from the compressed air outlet 24. Note that the compressed air dehumidifier unit of the present invention is not limited to a vertical installation of the compressed air dehumidifier 20; a certain level of effectiveness can be achieved as long as the condenser 12, compressed air inlet 22, and compressed air outlet 24 are positioned as shown in this embodiment.

In addition, in this embodiment, the condenser 12 is positioned along the upright surface of the casing 50, and is piped so that the refrigerant heated by being compressed by the compressor 11 flows in from the top of the condenser 12 and out from the bottom, as shown schematically by the dashed-dotted line in Figure 1. Note that the upright surface is not limited to a vertical surface when installed, but rather refers to a surface that is upright so as to be essentially placed vertically, and may be an actual wall surface or an imaginary surface.

In this configuration, the refrigerant that has been pressurized by the compressor 11 and heated to its highest temperature is supplied to the high-temperature, high-pressure region, which is the upper part of the heat exchanger section 12a of the condenser 12. The upper exhaust air (first exhaust air F1), which is the air that passes through to cool the upper part of the heat exchanger section 12a (high-temperature, high-pressure region), is at a higher temperature than the lower exhaust air (second exhaust air F2), which passes through the other part of the heat exchanger section 12a (the lower part, the medium-temperature, medium-pressure region) and exchanges heat. Air that is warmer than its surroundings flows as an ascending air current, and because the upper exhaust air is warmer than the lower exhaust air, the flow of the exhaust air is smoother, resulting in more efficient exhaust.

In this embodiment, the condenser 12 is installed vertically, and two cooling fans 13a, 13b are arranged side by side, one above the other, corresponding to the heat exchanger section 12a of the condenser 12. In this embodiment, as shown in FIG. 1, the casing 50 is formed in the shape of a vertically elongated rectangular box, with the heat exchanger section 12a of the condenser 12 facing the front and exposed, and the two cooling fans 13a, 13b are arranged on the interior side of the casing 50. As a result, the two cooling fans 13a, 13b blow cooling air (outside air) so as to draw it into the casing 50, and exhaust air (first exhaust air F1, second exhaust air F2), which is air that has passed through the heat exchanger section 12a, is exhausted from the exhaust port 51 provided at the top of the casing 50.

As shown by the dotted lines in FIG. 1, this configuration allows the exhaust air flow to be guided so that the first exhaust air F1, which is exhaust air from the upper cooling fan 13a, is exhausted higher in the casing 50, and the second exhaust air F2, which is exhaust air from the lower cooling fan 13b, is exhausted lower in the casing 50 than the exhaust air from the upper cooling fan 13a. In this embodiment, the exhaust ports 51 are composed of an exhaust port 51a on the top surface and an exhaust port 51b on the rear surface, and are provided on the top surface and the upper part of the rear surface of the casing 50, as shown in FIG. 1. The provision of the exhaust ports 51a and 51b in this manner allows the first exhaust air F1 and the second exhaust air F2 to be exhausted with as little interference as possible and with as little airflow resistance as possible. Furthermore, these exhaust ports 51a and 51b can be provided with a wide opening area and a high aperture ratio, for example, using a lattice-like member, to minimize airflow resistance. This lattice-like member functions to protect the exhaust ports 51a and 51b and ensure safety. In this embodiment, the casing 50 has its upright surfaces, such as the sides, surrounded by vertical wall panels 50a, except for the front where the heat exchanger section 12a is exposed and the upper part of the back where the exhaust port 51b is located.

In other words, in this embodiment, the compressed air outlet 24 and outlet piping 25 are positioned higher than the compressed air inlet 22 and inlet piping 23, with the outlet piping 25 extending from the top surface to the outside and the inlet piping 23 extending from the back surface to the outside. Therefore, in relation to the arrangement of the compressed air dehumidifier 20 within the casing 50, the first exhaust air F1 from the upper cooling fan 13a can be guided to hit the compressed air outlet 24 and outlet piping 25, and the second exhaust air F2 from the lower cooling fan 13b can be guided to hit the compressed air inlet 22 and inlet piping 23. Therefore, the compressed air outlet 24 and outlet piping 25 can be appropriately heated, and the compressed air inlet 22 and inlet piping 23 can be appropriately cooled. In this embodiment, the compressed air outlet 24 is located at the top of the side surface of the dehumidifier housing 21, and the outlet piping 25 is extended horizontally from the compressed air outlet 24 and then bent upward, forming a non-insulated area that facilitates heat exchange. In this embodiment, the compressed air inlet 22 is located at the top of the side surface of the dehumidifier housing 21, below the compressed air outlet 24, and the inlet piping 23 is extended horizontally, forming a non-insulated area that facilitates heat exchange.

In addition, in this embodiment, the distribution board 16 of the refrigeration cycle device 10 is positioned above the condenser 12 with a cooling gap 52 to allow air to be taken in for cooling. In this embodiment, the condenser 12 and distribution board 16 are exposed on the front surface (front face) of the casing 50, and air is drawn in from the front by the cooling fan 13, causing heat exchange to occur to cool the heat exchanger section 12a of the condenser 12, and the distribution board 16 is also cooled by the influence of the airflow generated by the cooling fan 13.

In other words, the provision of the cooling gap 52 makes it difficult for heat to be transferred from the condenser 12 to the switchboard 16, and also attracts outside air (external air) to be drawn into the airflow (first exhaust air F1) generated by the cooling fan 13, generating a secondary airflow F3 as shown in Figure 1. This secondary airflow F3 passes through the switchboard 16, including the area on the back side of the switchboard 16 where the inverter heat sink 17 is located, as an airflow that cools the switchboard 16, thereby effectively cooling the switchboard 16.

Furthermore, in this embodiment, a shielding member 53 is disposed between the switchboard 16 and the condenser 12 to prevent the exhaust air from the cooling fan 13 from directly hitting the switchboard 16. As shown in FIG. 1, the shielding member 53 in this embodiment is disposed between the upper cooling fan 13a of the condenser 12 and the heat sink 17 of the switchboard 16, in the form of a plate that slopes upward and functions as a rectifying plate, gradually narrowing the upward flow of air (first exhaust air F1) from the upper cooling fan 13a.

This effectively blocks the radiant heat generated by the condenser 12, and the Venturi effect, which occurs when the air flow is narrowed and its flow speed is increased, strengthens the flow of the secondary air flow F3 generated by the first exhaust air F1 generated by the cooling fan 13, thereby enhancing the cooling effect.

Next, an example of a compressed air dehumidifier unit according to the present invention, which uses exhaust air from the condenser 12 to cool the compressed air introduced into the compressed air dehumidifier 20, will be described in detail with reference to the accompanying drawings (Figures 1 to 3).

In the compressed air dehumidifier unit of the present invention, the compressed air inlet 22 and the inlet piping 23 extending from the compressed air inlet 22 are located at the top of the interior of the casing 50, the condenser 12 of the refrigeration cycle device 10 is located below the compressed air inlet 22, and the cooling fan 13 of the condenser 12 is positioned to blow air toward the interior of the casing 50. An exhaust port 51 in the exhaust casing 50 is provided at the top of the casing 50 so that the exhaust air generated when the air is heated as it passes through the heat exchanger section 12a of the condenser 12 by the air blown by the cooling fan 13 is exhausted through the space in which the compressed air inlet 22 and inlet piping 23 are disposed.

This has the particularly advantageous effect of allowing the exhaust air from the condenser 12 of the refrigeration cycle device 10 to be appropriately utilized to cool the compressed air introduced from the air compressor of the compressed air dehumidifier 20 to the compressed air inlet 22. In other words, the compressed air introduced into the compressed air dehumidifier 20 from the compressed air inlet 22 is heated by the compression action of the air compressor, but can be cooled by directing the exhaust air blown by the cooling fan 13 of the condenser 12 against the compressed air inlet 22 and inlet piping 23. This allows the compressed air introduced into the compressed air dehumidifier 20 to be cooled, the exhaust air from the condenser 12 to be effectively utilized, and energy savings to be achieved.

In addition, in this embodiment, as described above, the compressed air dehumidifier 20 is a vertically-installed type that is long vertically and is stored upright inside the vertically-elongated casing 50. This configuration allows for compact installation by reducing the installation floor space, as described above, and also allows for smooth flow of exhaust air from the condenser 12. Therefore, the exhaust air from the condenser 12 can be smoothly directed toward the compressed air inlet 22 and inlet piping 23, efficiently cooling the compressed air introduced into the compressed air outlet 24. Note that the compressed air dehumidifier unit of the present invention is not limited to a vertical installation of the compressed air dehumidifier 20; a certain level of effectiveness can be achieved as long as the condenser 12, compressed air inlet 22, and compressed air outlet 24 are positioned as described above.

In addition, in this embodiment, an air guide member 55 is disposed between the upper and lower cooling fans 13a, 13b, which branches the air exhausted by the upper cooling fan 13a, 13b so that the air exhausted by the upper cooling fan 13a is guided to heat the compressed air outlet 24 and outlet piping 25, and the air exhausted by the lower cooling fan 13b is guided to cool the compressed air inlet 22 and inlet piping 23. While the air guide member 55 in this embodiment shown in Figures 1 and 3 is formed in a flat plate shape, the present invention is not limited to this. It goes without saying that the air exhausted by the upper and lower cooling fans 13a, 13b may be branched as effectively as possible in relation to the exhaust port 51, as appropriate.

This allows the compressed air (product compressed air) discharged through the compressed air outlet 24 and outlet piping 25 to be efficiently heated (reheated) by the higher-temperature exhaust air from the upper cooling fan 13a, allowing appropriately dried and temperature-controlled product compressed air to be supplied to pneumatic equipment. Furthermore, the compressed air introduced into the compressed air dehumidifier 20 through the compressed air inlet 22 and inlet piping 23 can be efficiently cooled by the exhaust air from the lower cooling fan 13b, which is cooler than the exhaust air from the upper cooling fan 13a, thereby increasing the dehumidification efficiency of the compressed air dehumidifier 20. This improves the thermal efficiency of the system and achieves energy savings.

Next, specific examples of temperatures at each component will be presented to explain the conditions under which heat is exchanged at each component. For example, if the outside air temperature is 30°C, the temperature of the intake compressed air introduced into the compressed air dehumidifier 20 is approximately 80°C at most, the temperature of the exhaust air from the upper cooling fan 13a is 60-70°C, the temperature of the exhaust air from the lower cooling fan 13b is 40-60°C, and the temperature of the exhaust compressed air discharged from the compressed air outlet 24 is 20°C, the high-temperature exhaust air from the upper cooling fan 13a can efficiently heat (reheat) the exhaust compressed air, while the relatively low-temperature exhaust air from the lower cooling fan 13b can efficiently cool the intake compressed air. Furthermore, the heat sink 17 of the inverter disposed in the switchboard 16 will reach a temperature of, for example, 50-60°C, and will be effectively cooled because the secondary air flow F3 described above is outside air at, for example, 30°C.

Next, an example of a compressed air dehumidifier according to the present invention will be described in detail with reference to the accompanying drawings (Figures 4 and 5).

The compressed air dehumidifier 20 of the present invention dehumidifies primary-side compressed air introduced from a compressed air device (compressed air source) such as an air compressor through heat exchange, and discharges (supplies) the dehumidified secondary-side compressed air to pneumatic equipment. A two-stage heat exchanger, consisting of a first heat exchanger unit 30 and a second heat exchanger unit 40, is provided inside the dehumidifier housing. The first heat exchanger unit 30 pre-cools the primary-side compressed air and reheats the secondary-side compressed air, with a pre-cooling flow path for the primary-side compressed air and a reheating flow path 32 for the secondary-side compressed air arranged so as to intersect. The second heat exchanger unit 40 cools the compressed air pre-cooled in the first heat exchanger unit 30 with a cooling medium, causing condensation and dehumidifying the air.

The first heat exchanger section 30 and the second heat exchanger section 40 are arranged side by side vertically and are housed in a dehumidifier housing 21, which serves as a vertical pressure vessel. In this embodiment, the dehumidifier housing 21 is configured as a cylindrical body with both ends closed by a lower end head 28a and an upper end head 28b. In this embodiment, the upper part of the dehumidifier housing 21 is provided with an inlet (compressed air inlet 22) for primary-side compressed air introduced from the compressed air device, and an outlet (compressed air outlet 24) for discharging dehumidified secondary-side compressed air to pneumatic equipment. The compressed air outlet 24 is located above the compressed air inlet 22 and opens into a second small chamber 27, described below. Note that 21a and 21b are partition walls that support the second heat exchanger section 40 inside the dehumidifier housing 21, with partition wall 21a separating the first heat exchanger section 30 from a first small chamber 26 (described below), and partition wall 21b separating the first heat exchanger section 30 from a second small chamber 27.

By arranging the compressed air inlet 22 and compressed air outlet 24 at the top of the dehumidifier housing 21 in this way, the flow path can be configured so that the upper side is the side with the higher compressed air temperature for each heat exchange process. Due to the specific gravity of air (compressed air), which becomes lighter as the temperature increases, the compressed air tends to flow more smoothly, allowing for more efficient heat exchange and, as a result, more efficient dehumidification of the compressed air.

26 is the first small chamber, located below the first heat exchanger section 30 and the second heat exchanger section 40, into which the air outlet 47 of the second heat exchanger section and the inlet 34 of the reheating flow path open. It is designed so that drain water generated by condensation is discharged from the drain outlet 29 located at the bottom end.

That is, this first small chamber 26 is located at the lower end, which is one end side, of the dehumidifier housing 21, and serves as a retention space that guides compressed air discharged from the second heat exchanger section 40 to the reheating flow path 32 of the first heat exchanger section 30. Furthermore, in this embodiment, a drain hole for the drain outlet 29 is provided at the center of the bottom of the concave inner surface formed by the pressure vessel head plate (lower end head plate 28a) at the lower end of the first small chamber 26, and is configured to be connected to a drain discharge device. This allows condensed water (drain water) to be efficiently drained from the bottom of the lower end head plate 28a, which is the lower end plate of the dehumidifier housing 21.

27 is a second small chamber located above the first heat exchanger section 30 and the second heat exchanger section 40, into which the outlet 35 of the reheating flow path and the compressed air outlet 24 for discharging secondary compressed air to pneumatic equipment are opened, and which is designed to retain compressed air just before it is discharged.

In other words, this second chamber 27 is located at the upper end, which is the other end, of the dehumidifier housing 21, and serves as a retention space that guides the compressed air discharged from the reheating flow path 32 of the first heat exchanger section 30 to the compressed air outlet 24. Because the first chamber 26, second chamber 27, and reheating flow path 32 are provided in this way, the compressed air flows from bottom to top through the reheating flow path 32, causing the compressed air to be reheated, flow into the second chamber 27, and be discharged from the compressed air outlet 24.

In this embodiment of the compressed air dehumidifier according to the present invention, a temperature sensor 60 with a sensing unit 61 is provided on the side of the first chamber 26, at the air outlet 47 of the second heat exchanger unit 40. That is, the temperature sensor 60 in this embodiment is configured so that the sensing unit 61 is located at the bottom inside the dehumidifier housing 21, in the space where the compressed air is cooled by the cooling medium in the second heat exchanger unit 40 and is at its lowest temperature.

In this configuration, the temperature sensor 60 directly measures the temperature (dew point temperature) of the compressed air at its coolest point and dehumidified by condensing the moisture in the compressed air, allowing for the most accurate detection of the dew point temperature. Furthermore, if the operating status of the compressed air dehumidifier system of this embodiment drops to a low level or stops, the lowest-temperature compressed air will remain in a settled state due to its high density and weight. Furthermore, because the dehumidifier housing 21 is vertically long, convection is less likely to occur, making it easier for the low-temperature compressed air to remain in a settled state. Therefore, the low-temperature compressed air will stably remain at or near the air outlet 47 of the second heat exchanger section 40 in the first small chamber 26 where the temperature sensor 60 is located, making it less susceptible to external disturbances. Therefore, the temperature sensor 60 positioned as in this embodiment can accurately and stably monitor the dew point temperature and function optimally to ensure continued stable operation of the system.

In this embodiment, the first small chamber 26 is provided with an extended air passage 45 that extends downward so that the air outlet 47 of the second heat exchanger is located below the inlet 34 of the reheat flow path. This embodiment also includes a demister 48 that is disposed at the lower end of the extended air passage 45 and separates moisture from the compressed air discharged at the air outlet 47 of the second heat exchanger by passing the compressed air through it. The demister 48 used in this embodiment is made from thin metal wires such as stainless steel, which are woven to create a highly breathable coarse dust filter with uniformly spaced voids, and then appropriately layered and molded.

This demister 48 causes moisture in the compressed air to collide with the metal wires, causing the moisture to condense and separate from the compressed air into water particles, which then break up into larger droplets. It also acts to collect the water and create a water flow. This causes the water separated from the compressed air to form larger clumps that drip from the air outlet 47 of the second heat exchanger, preventing the separated moisture from returning to the dehumidified secondary compressed air and enhancing the dehumidification effect.

Furthermore, the extended air passage 45 positions the air outlet 47 of the second heat exchanger unit lower than the inlet 34 of the reheat flow path, thereby increasing the distance between the air outlet 47 and the inlet 34 of the reheat flow path. When the compressed air leaves the air outlet 47 of the second heat exchanger unit and enters the first chamber 26, the flow velocity of the compressed air can be sufficiently reduced, allowing water particles and water to be efficiently separated from the compressed air flow. This prevents the separated moisture from being sucked back into the dehumidified secondary compressed air, thereby enhancing the dehumidification effect. Furthermore, the extended air passage 45 bends (including reverses) the flow of compressed air, allowing the moisture to be separated by inertial force, thereby enhancing the dehumidification effect.

The above effects allow the relatively simple configuration of the extended ventilation passage section 45 to work synergistically with the demister 48, effectively separating compressed air and moisture while suppressing an increase in ventilation resistance (pressure loss).

In this embodiment, the sensing portion 61 at the tip of the temperature sensor 60 is inserted into the demister 48 so as to come into contact with the components that make up the demister 48. As mentioned above, the demister 48 in this embodiment is formed into a coarse dust filter using metal wire, and the sensing portion 61 of the temperature sensor 60 is placed in contact with the metal wire.

This allows the temperature sensor 60 to detect the dew point temperature more accurately and stably. Specifically, the demister 48 is cooled by the passage of low-temperature compressed air, which has been cooled by the second heat exchanger section 40 to its lowest temperature, and the temperature of the demister 48 becomes the same as that of the low-temperature compressed air. Furthermore, because the sensing section 61 is in contact with the components of the demister 48, which are solid compared to compressed air and therefore have high thermal conductivity, the temperature sensor 60 is less susceptible to the effects of airflow, which can be uneven, and can detect the averaged temperature more accurately and stably.

Furthermore, in this embodiment, as shown in FIG. 5, the temperature sensor 60 is attached by fixing the base portion 62 of the temperature sensor 60 to the portion of the dehumidifier housing 21 that forms the first small chamber 26. That is, in this embodiment, the temperature sensor 60 is configured so that the sensing portion 61 is inserted from the outside of the dehumidifier housing 21 and the base portion 62 is screwed into a female thread portion provided in the dehumidifier housing 21, thereby allowing it to be attached and detached to a component that constitutes the dehumidifier housing 21. This allows the temperature sensor 60 to be easily attached and detached, facilitating maintenance and management.

In addition, this embodiment may include a control device (not shown) that controls the operation of the refrigeration cycle apparatus 10 based on the detection information (monitored information) from the temperature sensor 60. For example, a control device may be provided that, based on the detection information from the temperature sensor 60, reduces the rotation speed of the electric motor that drives the compressor 11 through inverter control when the detected temperature (compressed air temperature) drops below a required temperature during operation of the compressor 11 of the refrigeration cycle apparatus 10, and increases the rotation speed of the electric motor that drives the compressor 11 through inverter control when the compressed air temperature exceeds the required temperature. In other words, the cooling load of the refrigeration cycle apparatus 10 can be more precisely controlled based on the precise monitoring information from the temperature sensor 60 of the present invention. Furthermore, for example, a control device may be provided that, based on the detection information from the temperature sensor 60, stops the operation of the compressor 11 when the detected temperature (compressed air temperature) drops below a predetermined temperature during operation of the compressor 11 of the refrigeration cycle apparatus 10, and resumes operation of the compressor 11 when the compressed air temperature exceeds the predetermined temperature while the compressor 11 is stopped. Furthermore, because restarting the refrigeration cycle apparatus 10 after it has been stopped is likely to result in energy loss, it is preferable to control the rotation speed of the electric motor using inverter control. Furthermore, controlling the operation of the refrigeration cycle apparatus 10 is not limited to controlling the compressor 11, but also includes controlling other components, such as the cooling fan 13 of the condenser 12. For example, if the sensing unit 61 is located at the top of the dehumidifier housing 21, and the system is stopped and the supply of compressed air is cut off, resulting in a no-load situation, heat gradually rises and accumulates at the top of the dehumidifier housing 21, potentially resulting in a false detection that the required temperature has been exceeded. In contrast, according to the present invention, the sensing unit 61 is located at the bottom of the dehumidifier housing 21, eliminating the possibility of false detection.

Next, a more specific example of the configuration of the compressed air dehumidifier according to the embodiment shown in FIGS. 4 and 5 will be described.
In this embodiment, the first heat exchanger section 30 and the second heat exchanger section 40 are configured such that the second heat exchanger section 40 is formed in a cylindrical shape with a closed upper end, and the first heat exchanger section 30, which is composed of a plurality of pipes (reheat pipes 33 that form the reheat flow path 32) arranged in a crescent shape surrounding the cylindrical side wall from one side, is arranged side by side with the second heat exchanger section 40, so that they are arranged side by side vertically and are built into the dehumidifier housing 21, which is formed in the shape of a vertical container.

The first heat exchanger section 30 of this embodiment is equipped with a pre-cooling flow path 31 for compressed air, which is formed by a space where the compressed air inlet 22 opens and which opens to the air inlet 44 of the second heat exchanger section, and a reheating flow path 32 that runs vertically within the pre-cooling flow path 31. The reheating flow path 32 is made up of multiple reheating pipes 33 arranged in a pipe shape, and is arranged to connect the first small chamber 26 and the second small chamber 27. In practice, in this first heat exchanger section 30, a large number of reheating pipes 33 are arranged as shown in Figure 5 to improve heat exchange performance.

In this embodiment, the second heat exchanger section 40 includes a built-in cylindrical body 41 that is vertically disposed in an eccentric position inside the dehumidifier housing 21, a refrigerant pipe 15a that passes a cooling medium inside the built-in cylindrical body 41, and heat exchange fins 15b attached to the refrigerant pipe 15a. As shown in Figure 4, 41b is the upper end end plate of the built-in cylindrical body, which closes the built-in cylindrical body 41.

Furthermore, the second heat exchanger section 40 of this embodiment is equipped with a plurality of refrigerant pipes 15a through which a cooling medium flows, numerous heat exchange fins 15b attached to the refrigerant pipes 15a, and a plurality of plates 43 arranged at intervals to cause the flow of compressed air in the cooled flow path 42 to bend in a zigzag pattern. Furthermore, the configuration of the refrigerant pipes 15a and heat exchange fins 15b of this second heat exchanger section 40 can be used, for example, as in this embodiment, as the evaporator 15 of a refrigerator (refrigeration cycle device 10 (see Figure 4)), allowing the compressed air to be efficiently cooled by the refrigerant circulating within the refrigerant pipes 15a.

That is, in this embodiment, the cooling medium is the refrigerant of the refrigeration cycle device 10, and the evaporator 15 is disposed as a component of the second heat exchanger section 40. However, the invention is not limited to this. Even if the cooling medium is cooling water supplied from a cold water source, the operation (cooling load) of the compressed air dehumidifier 20 can be appropriately controlled by appropriately controlling the amount of cooling water supplied to the second heat exchanger section 40 via a flow control valve or the like based on detection information from the temperature sensor 60.

The extended vent passage 45 extends downward through the built-in cylindrical body 41, excluding the portion where the refrigerant pipe 15a extends to the outside, and is open at the bottom end. The side eccentrically positioned close to the inner wall of the dehumidifier housing 21 is cut out, creating a D-shaped horizontal cross section (see Figure 3 of Patent Document 2). The extended vent passage 45 in this embodiment is formed by a cylindrical member 46 with a D-shaped horizontal cross section, and is open except for the support portion that supports the demister 48 on its lower end surface. The support portion that supports the demister 48 in this embodiment is formed in a lattice pattern, increasing the open area ratio.

This extended air vent passage 45 allows for optimal placement of the refrigerant piping 15a, which must extend from the interior to the exterior of the dehumidifier housing 21. The D-shaped cylindrical member 46 that forms this extended air vent passage 45 is composed of a sidewall peripheral surface 46a, whose horizontal cross section corresponds to the arc of the D, and a sidewall flat surface 46b, whose horizontal cross section corresponds to the chord of the D. This configuration enhances the dehumidifying effect by appropriately guiding the flow of compressed air. Note that 41a is a partition plate that serves as an end plate that closes off part of the lower end of the built-in cylindrical main body 41, allowing for the rational formation of the extended air vent passage 45, whose horizontal cross section is D-shaped.

Furthermore, the extended ventilation path section 45 of this embodiment can be appropriately configured so that the side wall flat section 46b, which forms the chord portion of the extended ventilation path section 45 whose horizontal cross section is D-shaped, is provided with a side opening 47b that forms part of the air outlet 47 of the second heat exchanger section at the lower end side of the side wall flat section 46b (see Figure 4 of Patent Document 2).

In this way, in addition to the lower end opening 47a on the lower end surface of the D-shaped cylindrical member 46, a side opening 47b can be appropriately formed on the side wall flat portion 46b, which allows the air outlet 47 of the second heat exchanger section to be enlarged, appropriately suppressing an increase in airflow resistance and improving performance.

The side opening 47b is formed on the surface opposite the position where the multiple reheat pipes 33 are arranged, so as to be as far away as possible from the reheat flow path inlet 34 (the surface on the side where the outer surface of the built-in cylindrical body 41 is closest to the inner surface of the dehumidifier housing 21, due to the second heat exchanger section 40 being located eccentrically within the dehumidifier housing 21). In this way, since the side opening 47b is formed on the sidewall flat surface section 46b on the D-shaped cutout side, a sufficient distance from the inner surface of the dehumidifier housing 21 is maintained, preventing an increase in the flow rate of the compressed air being blown out. This prevents water particles from being drawn into the compressed air flow, being blown up, and being re-scattered, improving dehumidification performance.

Furthermore, as described above, the compressed air dehumidifier of this embodiment can be installed vertically while still achieving dehumidification performance above the required level, and the vertical installation configuration allows for free selection of the installation position relative to the direction of the compressed air inlet 22 and compressed air outlet 24 around the axis of the dehumidifier housing 21. This provides greater flexibility in the piping connected to the compressed air inlet 22 and compressed air outlet 24. For example, when connecting two compressed air dehumidifiers of this embodiment, the connecting piping can be made shorter compared to conventional horizontally installed units, resulting in the advantage of a more rational configuration.

The present invention has been described above in various ways using preferred embodiments, but the present invention is not limited to these embodiments, and of course many modifications can be made without departing from the spirit of the invention.

10 Refrigeration cycle device 11 Compressor 12 Condenser 12a Heat exchanger section 13 Cooling fan 13a Upper cooling fan 13b Lower cooling fan 14 Expansion valve 15 Evaporator 15a Refrigerant piping 15b Heat exchange fins 16 Distribution board 17 Heat sink 20 Compressed air dehumidifier 21 Dehumidifier housing 21a Partition wall section 21b Partition wall section 22 Compressed air inlet 23 Inlet piping 24 Compressed air outlet 25 Outlet piping 26 First small chamber 27 Second small chamber 28a Lower end end plate 28b Upper end end plate 29 Drain discharge port 30 First heat exchanger section 31 Pre-cooling flow path 32 Reheating flow path 33 Reheating pipe 34 Inlet of reheating flow path 35 Outlet of reheating flow path 40 Second heat exchanger section 41 Built-in cylindrical body 41a Partition plate 41b Upper end end plate 42 of built-in cylindrical body, cooled flow path 43, plate 44, air inlet 45 of second heat exchanger section, extended ventilation path section 46, D-shaped cylindrical member 46a, side wall peripheral surface section 46b, side wall flat section 47, air outlet 47a of second heat exchanger section, lower end opening 47b, side opening 48, demister 50, casing 50a, vertical wall face plate 51, exhaust port 51a, top exhaust port 51b, rear exhaust port 52, cooling gap 53, shielding member 55, air guide member 60, temperature sensor 61, sensing section 62, base section F1, first exhaust air F2, second exhaust air F3, secondary air flow

Claims (6)

A compressed air dehumidifier in which a heat exchanger is provided in two stages, a first heat exchanger unit and a second heat exchanger unit, inside a dehumidifier housing so as to dehumidify primary-side compressed air introduced from a compressed air device by heat exchange and discharge the dehumidified secondary-side compressed air to pneumatic equipment, the first heat exchanger unit is provided by arranging a pre-cooling flow path for the primary-side compressed air and a reheating flow path for the secondary-side compressed air so as to pre-cool the primary-side compressed air and reheat the secondary-side compressed air so as to intersect, and the second heat exchanger unit is provided to cool the compressed air pre-cooled in the first heat exchanger unit with a cooling medium to cause condensation and dehumidify the compressed air,
the first heat exchanger unit and the second heat exchanger unit are disposed adjacent to each other in a vertically long manner and are built into the dehumidification device housing as a vertically long pressure vessel,
a first small chamber located below the first heat exchanger section and the second heat exchanger section, into which an air outlet of the second heat exchanger section and an inlet of the reheating flow path are opened, and into which drain water generated by condensation is discharged from a drain outlet provided at a lower end of the first small chamber;
a second small chamber located above the first heat exchanger section and the second heat exchanger section, into which an outlet of the reheating flow path opens and into which a compressed air outlet for discharging the secondary-side compressed air to a pneumatic device opens, the second small chamber retaining the compressed air immediately before being discharged;
a temperature sensor having a sensing unit disposed on the side of the first small chamber at an air outlet of the second heat exchanger unit ,
an extended air passage portion extending downward so that an air outlet of the second heat exchanger portion is located below an inlet of the reheating flow passage;
a demister disposed at a lower end of the extended air passage portion and configured to separate moisture from the compressed air discharged at an air outlet of the second heat exchanger portion by passing the compressed air therethrough,
A compressed air dehumidifier characterized in that the sensing portion at the tip of the temperature sensor is inserted into the demister so as to come into contact with a component constituting the demister . A compressed air dehumidifier in which a heat exchanger is provided in two stages, a first heat exchanger unit and a second heat exchanger unit, inside a dehumidifier housing so as to dehumidify primary-side compressed air introduced from a compressed air device by heat exchange and discharge the dehumidified secondary-side compressed air to pneumatic equipment, the first heat exchanger unit is provided by arranging a pre-cooling flow path for the primary-side compressed air and a reheating flow path for the secondary-side compressed air so as to pre-cool the primary-side compressed air and reheat the secondary-side compressed air so as to intersect, and the second heat exchanger unit is provided to cool the compressed air pre-cooled in the first heat exchanger unit with a cooling medium to cause condensation and dehumidify the compressed air,
the first heat exchanger unit and the second heat exchanger unit are disposed adjacent to each other in a vertically long manner and are built into the dehumidification device housing as a vertically long pressure vessel,
a first small chamber located below the first heat exchanger section and the second heat exchanger section, into which an air outlet of the second heat exchanger section and an inlet of the reheating flow path are opened, and into which drain water generated by condensation is discharged from a drain outlet provided at a lower end of the first small chamber;
a second small chamber located above the first heat exchanger section and the second heat exchanger section, into which an outlet of the reheating flow path opens and into which a compressed air outlet for discharging the secondary-side compressed air to a pneumatic device opens, the second small chamber retaining the compressed air immediately before being discharged;
a temperature sensor having a sensing unit disposed on the side of the first small chamber at an air outlet of the second heat exchanger unit ,
A compressed air dehumidifier characterized in that the temperature sensor is attached by fixing a base portion of the temperature sensor to a portion of the dehumidifier housing that forms the first small chamber . 2. The compressed air dehumidifier according to claim 1 , wherein the temperature sensor is attached by fixing a base portion of the temperature sensor to a portion of the dehumidifier housing that forms the first small chamber. A compressed air dehumidifier according to any one of claims 1 to 3, characterized in that the cooling medium is a refrigerant from a refrigeration cycle device equipped with a compressor, a condenser, an expansion valve, and an evaporator, and the evaporator is a component of the second heat exchanger unit. The compressed air dehumidifier of claim 4, further comprising a control device that controls the operation of the refrigeration cycle device based on information detected by the temperature sensor. A compressed air dehumidifier unit in which the compressed air dehumidifier according to claim 4 and the refrigeration cycle device are housed inside a casing,
the dehumidifier housing has a compressed air inlet through which compressed air is introduced and a compressed air outlet through which dehumidified compressed air is discharged,
the compressed air outlet and an outlet pipe extending from the compressed air outlet are disposed at an upper portion inside the casing,
the condenser of the refrigeration cycle device is disposed below the compressed air outlet, and a cooling fan of the condenser is disposed so as to blow air toward the inside of the casing,
an exhaust port in the casing for the exhaust air is provided at an upper portion of the casing so that exhaust air generated by air being heated as it passes through the heat exchanger portion of the condenser by the air blown by the cooling fan is exhausted through a space in which the compressed air outlet and the outlet piping are arranged;
the compressed air inlet and an inlet pipe extending from the compressed air inlet are disposed at an upper portion inside the casing,
the condenser of the refrigeration cycle device is disposed below the compressed air inlet, and a cooling fan of the condenser is disposed so as to blow air toward the inside of the casing,
A compressed air dehumidifier unit characterized in that an exhaust port in the casing for the exhaust air is provided at the top of the casing so that the exhaust air generated when air is heated as it passes through the heat exchanger section of the condenser by the blowing of the cooling fan is exhausted through the space in which the compressed air inlet and the inlet piping are arranged.