Compressed Air Circuit

Abstract

To provide a compressed pneumatic circuit which prevents temperature drop of compressed air and drain generation by contact of outside air, and thereby prevents the drain from flowing into an oil content removal device and can achieve maximum performance.SOLUTION: A compressed pneumatic circuit includes at least a compressor, a cyclone separator, a refrigeration type air drier and an oil content removal device, wherein the cyclone separator and the refrigeration type air drier are arranged in close proximity to each other through a first connection pipe for feeding compressed air, and the refrigeration type air drier and the oil content removal device are arranged in close proximity to each other through a second connection pipe for feeding compressed air.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a compressed air circuit, and more particularly to a compressed air circuit in which an air dryer and an oil removal device, which constitute the compressed air circuit, are disposed in close proximity to each other. [Background technology]

[0002] Compressed air generated by a compressor is used for various purposes, such as spray painting, automatic train door opening and closing devices, etc. Depending on the purpose of the compressed air, various devices such as air dryers, cyclone separators, and oil removers are installed in the air pressure circuit between the compressor and the compressed air discharged.

[0003] However, in the conventional compressed air circuit configuration, when the piping connecting various devices is extended due to the arrangement of the devices, the contact area with the outside air increases, the temperature of the compressed air passing through it drops, the amount of saturated water vapor decreases, and drainage is easily generated in the piping. In addition, there is also a problem that the generated drainage flows into the oil removal device used to remove oil from the compressed air, accelerating the deterioration of the removal material filled therein. Therefore, there was a need for technology that could prevent the temperature of the compressed air from decreasing due to the extension of the piping, while also preventing moisture from entering the oil removal device.

[0004] Therefore, the applicant developed a technology in which an air dryer and an oil-water separator are integrated, and the drain generated by drying the compressed air generated by the compressor with the air dryer is passed through the oil-water separator to purify it and discharge it, and proposed the technology in Patent No. 3368429 (Patent Document 1). In addition, the applicant developed a technology in which a cyclone separator and an oil adsorption device are provided to separate and remove moisture and oil mist in the compressed air generated by the compressor, and the clean compressed air is sent to the subsequent stage, and proposed the technology in Patent No. 6713596 (Patent Document 2).

[0005] However, while the proposal in Patent Document 1 is useful for improving the efficiency of drain treatment by shortening the drain piping from the air dryer to the oil-water separation device, the purpose of the oil-water separation device is to separate and remove the drain discharged from the air dryer, and it does not solve the above-mentioned problems. Furthermore, according to the proposal in Patent Document 2, although the cyclone separator is useful for separating and removing moisture and foreign matter, the compressed air that is sent out remains at a high temperature, and the temperature difference with the inside of the oil adsorption device causes the temperature of the compressed air to drop, which can result in drainage being generated within the device, so the above-mentioned problems are still not solved.

[0006] The applicant focused on the phenomenon in conventional compressed air circuits as described above, in which drain is generated due to temperature changes accompanying the extension of the piping, and came up with the idea of ​​shortening the piping distance by changing the arrangement of the cyclone separator, air dryer, and oil removal device.He developed a compressed air circuit in which the cyclone separator, refrigerated air dryer, and oil removal device are arranged in close proximity to each other and the connecting pipes connecting each device are shortened, thereby preventing a drop in the temperature of the compressed air and the generation of drain due to contact with outside air, and preventing drain from flowing into downstream equipment, and has thus proposed the "compressed air circuit" of the present invention. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Patent No. 3368429 [Patent Document 2] Patent No. 6713596 Summary of the Invention [Problem to be solved by the invention]

[0008] In view of the above problems, an object of the present invention is to provide a compressed air pressure circuit that can prevent the temperature drop of compressed air and the generation of drainage due to contact with outside air, thereby preventing drainage from flowing into an oil removal device and maximizing performance. [Means for solving the problem]

[0009] In order to solve the above problems, the present invention provides a compressed air circuit having at least a compressor, a cyclone separator, a refrigerated air dryer, and an oil removal device, in which the cyclone separator and the refrigerated air dryer are arranged in close proximity via a first connecting pipe that supplies compressed air, and the refrigerated air dryer and the oil removal device are arranged in close proximity via a second connecting pipe that supplies compressed air.

[0010] In addition, the present invention employs a means in which the second connecting pipe has no more than three bent portions, and the second connecting pipe is ultimately connected to the oil removal device in a state in which it stands approximately vertically upward via the bent portions.

[0011] Furthermore, the present invention employs a means in which the second connecting pipe has one bent portion. Effect of the Invention

[0012] According to the compressed air circuit of the present invention, the cyclone separator and refrigerated air dryer are arranged in close proximity via a first connecting pipe, and the refrigerated air dryer and oil removal device are arranged in close proximity via a second connecting pipe. By shortening the length of each connecting pipe, the area where the connecting pipes come into contact with the outside air is also reduced, making it possible to prevent a drop in the temperature of the compressed air sent into the connecting pipe. In addition, since no drain enters the refrigerated air dryer, the performance of the refrigerated air dryer is maintained at a dew point temperature according to the specifications. Furthermore, since the oil mist is cooled to the dew point temperature of the compressed air before entering the oil removal device, the performance of the oil removal device is maximized and the oil mist is effectively adsorbed and removed. These are excellent effects.

[0013] Furthermore, according to the compressed air circuit of the present invention, the second connecting pipe has no more than three bends, and the second connecting pipe is ultimately connected to the oil removal device in a state where it stands approximately vertically upward at the bends. Therefore, the compressed air flow path in the oil removal device is also approximately vertically upward. As a result, the oil separated and removed in the oil removal device hangs downward due to gravity, making it possible to prevent oil from leaking into downstream equipment using compressed air.

[0014] Furthermore, according to the compressed air circuit of the present invention, by providing only one bent portion in the second connecting pipe, the compressed air flowing into the second connecting pipe comes into contact with the inner wall only once due to the bending, thereby achieving the excellent effect of making it possible to prevent the compressed air from being cooled or losing pressure due to contact with the inner wall while allowing it to flow into the oil removal device. [Brief description of the drawings]

[0015] [Figure 1] 1 is an explanatory diagram showing an embodiment of an air compressor according to the present invention; [Diagram 2] 1 is an explanatory diagram showing an embodiment of an air compressor according to the present invention; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] The compressed air circuit 1 according to the present invention is characterized in that the cyclone separator 7, the refrigerated air dryer 3, and the oil removal device 4 are arranged in close proximity to each other. Hereinafter, an embodiment of a compressed air pressure circuit 1 according to the present invention will be described with reference to the drawings.

[0017] The compressed air circuit 1 according to the present invention is not limited to the embodiment described below, but can be modified as appropriate within the scope of the technical idea of ​​the present invention, i.e., within the scope of the shape, dimensions, materials, etc. that can achieve the same functional effects.

[0018] Fig. 1 is an explanatory diagram showing an embodiment of a compressed air pressure circuit 1 according to the present invention, specifically, an explanatory diagram of an aspect in which the second connecting pipe 10b has three bent portions K. Fig. 2 is an explanatory diagram showing another embodiment of a compressed air pressure circuit 1 according to the present invention, specifically, an explanatory diagram of an aspect in which the second connecting pipe 10b has one bent portion K. The compressed air circuit 1 of the present invention comprises at least a compressor 2, a cyclone separator 7, a refrigerated air dryer 3, and an oil removal device 4 (hereinafter, these may be referred to as various devices). The compressed air generated by the compressor 2 is sent to the refrigerated air dryer 3 after drain is separated therefrom in the cyclone separator 7, and after being dried by the refrigerated air dryer 3, it is sent to the oil removal device 4 via a connecting pipe 10, and is supplied to a downstream compressed air-using device as compressed air from which oil has been removed.

[0019] A flow path for compressed air is formed from the compressor 2 to the compressed air using equipment through air piping 11 made of hollow pipes arranged between the compressor 2 and the cyclone separator 7 and between the oil removal device 4 and the compressed air using equipment arranged downstream, a first connecting pipe 10a made of hollow pipes arranged between the cyclone separator 7 and the refrigerated air dryer 3, and a second connecting pipe 10b made of hollow pipes arranged between the refrigerated air dryer 3 and the oil removal device 4. Although there is no particular limitation on the diameter of the air pipe 11 and each connecting pipe 10 connecting various devices, it is possible to reduce the pressure loss of the compressed air by making the respective diameters the same. In addition, although there is no particular limitation on the length of the air pipe 11, it is possible to enhance the effect of preventing a drop in the temperature of the compressed air sent into the air pipe 11 by shortening the length of the air pipe 11 and narrowing the area in contact with the outside air.

[0020] The compressor 2 is a device that compresses air and generates compressed air pressurized to a predetermined pressure (for example, 0.7 MPa). Compressor 2 comes in various types, such as reciprocating, rotary, and centrifugal, depending on the structure for generating compressed air. Also, there are types such as oil-lubricated and oil-free, depending on whether lubricating oil is used. There is no particular limitation on the type of compressor 2 used in the present invention, and any type and structure can be used. In addition, air piping 11a is connected to compressor 2 for sending the generated compressed air to cyclone separator 7. The air compressed by the compressor 2 contains not only water vapor and dust but also oil floating in the vicinity, and when the compressed air is generated, it is sent out as oil mist. If the compressor 2 is an oil-lubricated type, the mist of the lubricating oil used there is contained in the compressed air generated as oil.

[0021] The cyclone separator 7 is a device that separates and removes drainage from the compressed air sent from the compressor 2 via the air piping 11a. The structure of the cyclone separator 7 is not particularly limited and any conventionally known structure may be used, but a structure in which centrifugal force is generated by circularly moving the cyclone separator 7 at high speed near the outer periphery of the inner wall along a flow path provided in a spiral shape, causing the drain, which has more mass than air, to collide against the inner wall, separating the compressed air from the drain, and discharging the separated drain outside the cyclone separator 7, is generally used. The drain separated and removed by the cyclone separator 7 is discharged to the outside via a drain pipe 12 provided at the bottom of the cyclone separator 7, as shown in FIG. Then, the compressed air from which the drain has been removed in the cyclone separator 7 flows into the refrigerated air dryer 3 via the first connecting pipe 10a.

[0022] The cyclone separator 7 is preferably disposed in the vicinity of the downstream refrigerated air dryer 3. The term "close" means that the compressed air leaving the cyclone separator 7 is close enough to prevent drainage from occurring in the first connecting pipe 10a due to a temperature drop while the compressed air passes through the first connecting pipe 10a and reaches the refrigerated air dryer 3. The shorter the distance, the better, but for example, a possible embodiment is that the distance between the first connecting pipe 10a is 0.5 m to 1 m on each side. If the distance is shorter than 0.5 m, it is expected that the piping and installation work of the first connecting pipe 10a will become more difficult, and it is also expected that an unnecessary bend K will need to be provided in the middle of the first connecting pipe 10a. Also, if the distance is longer than 1 m, the first connecting pipe 10a will be longer, which will make it more susceptible to the effects of outside air and more likely to generate drainage.

[0023] The refrigerated air dryer 3 is a device for drying the compressed air sent from the cyclone separator 7 via the first connecting pipe 10a, and removing moisture. There are various types of air dryers, such as refrigeration type, hollow fiber membrane type, and adsorption type, depending on the method of removing moisture, but the air dryer used in the present invention is a refrigeration type air dryer 3. The refrigeration type air dryer 3 is a device that uses the latent heat of evaporation of a refrigerant to cool compressed air and condense and remove the contained moisture, and is preferable because it can be introduced relatively inexpensively. In addition, in the present invention, by interposing a cyclone separator 7 in the upstream stage, drain does not enter the refrigeration type air dryer 3, so the performance of the refrigeration type air dryer 3 maintains the dew point temperature as specified. The dried compressed air from which moisture has been removed is sent via a connecting pipe 10 to an oil removal device 4 disposed downstream, where the oil is removed. In addition, in the process of condensing and removing moisture contained in the compressed air, the refrigerated air dryer 3 generates drainage due to a decrease in the amount of saturated water vapor caused by cooling, so as shown in Figure 1, a drainage pipe 12 is provided at the bottom of the refrigerated air dryer to discharge the drainage, and the drainage that flows into the drainage pipe 12 is discharged to the outside.

[0024] The connecting pipe 10 is a piping made of a hollow tube, and includes a first connecting pipe 10a that connects the cyclone separator 7 and the refrigeration type air dryer 3, and a second connecting pipe 10b that connects the refrigeration type air dryer 3 and the oil removal device 4. Regarding the diameter of the connecting pipe 10 teeth, By making the diameter the same as that of the air pipe 11 that forms the compressed air flow path, it is possible to reduce the pressure loss of the compressed air. Also, by shortening the length of the connecting pipe 10 and reducing the area in contact with the outside air, it is possible to reduce the temperature change on the inner wall of the connecting pipe 10, prevent a drop in the temperature of the compressed air sent into the connecting pipe 10, and prevent the generation of drainage due to a decrease in the amount of saturated water vapor, which contributes to a reduction in the amount of drainage (moisture) entering the oil removal device 4 connected in the subsequent stage.

[0025] As shown in FIG. 1 and FIG. 2, the first connecting pipe 10a used to connect the cyclone separator 7 and the refrigerated air dryer 3 is a straight pipe without any bends in the middle. That is, the compressed air outlet of the cyclone separator 7 and the compressed air inlet of the refrigerated air dryer 3 are at the same level. In contrast, the second connecting pipe 10b used to connect the refrigerated air dryer 3 and the oil removal device 4 may have a bent part K in the middle due to the relationship between the respective connection positions (the positions of the outlet and the inlet). In this case, when the compressed air passes through the bent part K of the second connecting pipe 10b, it collides with the inner wall of the bent part K due to a change in the traveling direction, and the moisture in the compressed air adheres to the inner wall of the bent part K due to such collision and turns into water droplets, which is assumed to generate drainage. Therefore, it is preferable to have as few bent parts as possible, and it is preferable to have three or less bent parts K, and more preferably, it is preferable to have only one bent part K. By adopting this embodiment, it is possible to reduce the collision of the compressed air with the inner wall and suppress the generation of drainage in the second connecting pipe 10b.

[0026] 1 and 2, in the present invention, the second connecting pipe 10b just before flowing into the oil removal device 4 is connected to the oil removal device 4 in a state where it rises up approximately vertically from the final bent part K'. By adopting such a configuration, the compressed air that flows into the oil removal device 4 is sent toward the air pipe 11b provided above while resisting gravity inside the oil removal device 4, and even if the oil separated and removed in the oil removal device 4 condenses, it hangs down due to gravity, making it possible to prevent the oil from leaking out to downstream equipment. Although not shown, by disposing the oil removal device 4 above the refrigerated air dryer 3, it is possible to eliminate the bent portion K in the connecting pipe 10 and connect the refrigerated air dryer 3 and the oil removal device 4 with a straight pipe. When this embodiment is adopted, it is also possible to make the length of the connecting pipe 10 extremely short, or to directly connect the air supply port of the refrigerated air dryer 3 and the air inlet of the oil removal device 4 without using the connecting pipe 10, making it possible to form a flow path that does not cause a drop in temperature or the generation of drainage.

[0027] The drain trap 5 is provided in the drain pipe 12 and mechanically discharges to the outside the drain that has flowed into the drain pipe 12 from the cyclone separator 7 or the refrigerated air dryer 3, and makes it possible to prevent compressed air from being discharged together with the drain when it is discharged. The drain trap 5 may be of any known type, and may be of an electromagnetic or float type depending on the drainage method, but is not limited thereto.

[0028] It is preferable that a valve 6 capable of adjusting the flow rate in the pipe is provided at a predetermined central location between the drain pipe 12 and the drain trap 5. By adopting this configuration, it becomes easy to adjust the flow rate of the drain discharged from the drain pipe 12, and it becomes possible to cut off the relevant flow path during maintenance of various devices or when an abnormality occurs.

[0029] The oil removal device 4 separates and removes oil contained in the dried compressed air sent from the refrigerated air dryer 3 via the second connecting pipe 10b by bringing the air into contact with a filler provided in the oil removal device 4, and sends the resulting air to the subsequent stage as clean compressed air. The oil removal device 4 is disposed near the refrigerated air dryer 3, and separates and removes oil from the compressed air that flows in from the connecting pipe 10. The oil is then discharged into the air piping 11b, where the compressed air is sent to the equipment that uses the compressed air that is connected downstream. There are no particular limitations on the shape or performance of the oil removal device 4, and it is sufficient to use a conventionally known device that has a shape and performance capable of supplying clean compressed air to a compressed air-using device connected downstream, taking into account the oil that may be generated during the air compression process and in various devices. Similarly, there is no limitation on the filler to be placed in the oil removal device 4, and conventionally known materials such as, for example, cubic or rectangular shaped polyethylene, polypropylene, polyethylene terephthalate, amines coated or impregnated into nonwoven fabric, zeolite, which is a porous mineral, activated carbon, etc., can be used to achieve the above-mentioned performance. In addition, in the present invention, by providing a refrigeration type air dryer 3 at the front stage, the oil mist is also cooled to the dew point temperature of the compressed air before entering the oil removal device 4, so that the performance of the oil removal device 4 is maximized and the oil mist can be effectively adsorbed and removed.

[0030] The refrigerated air dryer 3 and the oil removal device 4 are disposed in close proximity to each other. Close proximity means a distance close enough that drainage due to a temperature drop does not occur in the second connecting pipe 10b while the compressed air leaving the refrigerated air dryer 3 reaches the oil removal device 4 through the second connecting pipe 10b. The shorter the distance, the better, but taking into consideration the presence of the bent portion K, for example, a mode in which the distance between them is within 1 m in the lateral and vertical directions can be considered. If the distance is shorter than 1 m, even if the refrigerated air dryer 3 and the oil removal device 4 are disposed in a negative distance state with a partial overlap in the lateral distance or vertical distance, connection by the second connecting pipe 10b is possible without any problem. Conversely, if the distance is greater than 1 m, the second connecting pipe 10b is longer by that amount, and therefore they are more susceptible to the influence of outside air and more likely to generate drainage.

[0031] The main operations and functions of the compressed air circuit 1 consisting of the above-mentioned components will be described with reference to Figs. The compressed air circuit 1 comprises a compressor 2, a cyclone separator 7, a refrigeration type air dryer 3, and an oil removal device 4, with the cyclone separator 7, the refrigeration type air dryer 3, and the oil removal device 4 arranged in close proximity to each other. First, compressed air is generated in the compressor 2 and flows into the cyclone separator 7 via the air piping 11a. The compressed air from which drain has been separated and removed in the cyclone separator 7 flows into the refrigerated air dryer 3 via the first connecting pipe 10a. The compressed air cooled and dried in the air dryer 3 flows into the second connecting pipe 10b, and passes through the second connecting pipe 10b which finally rises almost vertically upward at the final bending part K' while contacting the inner wall of the bending part K in the second connecting pipe 10b, and is sent to the oil removing device 4. The compressed air that flows into the oil removing device 4 becomes clean compressed air from which oil has been removed by contacting the filler, and is sent to the downstream compressed air using equipment via the air piping 11b.

[0032] Although the basic configuration and operation / effect of the compressed air pressure circuit 1 according to the present invention have been described above, the present invention is not limited to the configuration shown in the above embodiment and drawings. For example, by arranging the compressor 2, the cyclone separator 7, the refrigerated air dryer 3, and the oil removal device 4 in one housing, the air pipe 11 connecting the devices can be shortened, and the compressed air pressure circuit 1 can be made space-saving as a whole. In addition, the shortening of the length of the air pipe 11 reduces the temperature change of the inner wall of the air pipe 11 due to contact with the outside air, as with the connecting pipe 10, and suppresses the generation of drainage due to a decrease in the temperature of the compressed air, thereby providing an excellent effect of preventing the performance degradation of the oil removal device 4 due to moisture adhesion. Furthermore, the compressed air pressure circuit 1 according to the present invention employs a configuration including at least the cyclone separator 7, but the configuration may be such that the cyclone separator 7 is replaced with another device that is capable of separating and removing drainage from compressed air like the cyclone separator 7.

[0033] As described above, the compressed air circuit 1 of the present invention, by arranging the cyclone separator 7, refrigeration type air dryer 3, and oil removal device 4 in close proximity, makes it possible to shorten the length of the connecting pipe 10 connecting them, preventing a decrease in the temperature of the compressed air and a decrease in the amount of saturated water vapor that may occur by passing through the connecting pipe 10, and also makes it possible to prevent performance degradation of the oil removal material in the oil removal device 4 due to moisture adhesion. [Industrial Applicability]

[0034] The present invention can be used as a compressed air circuit with excellent oil removal performance in any field that requires oil-free compressed air, such as food processing, electronic component painting, car body painting, etc. Therefore, it is considered that the "compressed air circuit" according to the present invention has great industrial applicability. [Explanation of symbols]

[0035] 1 Compressed air circuit 2. Compressor 3 Refrigerated air dryer 4 Oil removal device 5 Drain Trap 6 Valves 7 Cyclone Separator 10 Connecting pipe 10a First connecting pipe 10b Second connecting pipe 11 Air piping 11a Air piping 11b Air piping 12 Drain piping K bent part K' final bend

Claims

1. A compressed air circuit including at least a compressor, a cyclone separator, a refrigerated air dryer, and an oil removal device, the compressor and the cyclone separator are disposed via an air pipe for supplying compressed air, and the oil removal device and the compressed air-using device are disposed via an air pipe for supplying compressed air, the cyclone separator and the refrigerated air dryer are disposed adjacent to each other within 0.5 m to 1 m via a first connecting pipe which is a straight pipe for supplying compressed air, and the refrigerated air dryer and the oil removal device are disposed adjacent to each other within 0.5 m to 1 m via a second connecting pipe which is a straight pipe or a curved pipe having a bend for supplying compressed air, The air pipe, the first connecting pipe, and the second connecting pipe have the same diameter, The second connecting pipe is connected to an oil removing device in a state where it rises substantially vertically upward.

2. 2. The compressed air circuit according to claim 1, wherein, in the case where the second connecting pipe is a curved pipe, the second connecting pipe has at most three bent portions.

3. 3. The compressed air circuit according to claim 2, wherein the second connecting pipe has one bent portion.

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