JPH09113131A - Hot air drying device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve a drying efficiency during a hot air drying operation by a method wherein a nozzle header having many nozzle holes therein is installed in a drying chamber, compressed air is injected from nozzle holes to agitate high temperature air in the drying chamber. SOLUTION: Compressed air is supplied from a compressed air supplying device 3 to a nozzle header 11 through an air dryer 4, a pressure regulating valve 5 and an air filter 6. The compressed air is blown out at a high speed from nozzle holes 12 into a drying chamber 1, and struck against a cleaned item 7 while agitating the surrounding high temperature air and entangling it. At this time, the high temperature air is supplied from a hot air generating device 2 composed of a blower 8 and a heater 9 to a lower part of a drying chamber 1, gradually blown from a blowing-out port 10 so as to circulate the high temperature air in the drying chamber 1. With such an arrangement as above, it is possible to improve a drying efficiency during the hot air drying operation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drying device for washing machine parts, precision parts, etc., especially for products and parts having deep bag holes or complicated shapes, using a water-based or hydrocarbon-based cleaning agent. The present invention relates to a hot air drying device after cleaning.

[0002]

2. Description of the Related Art As a device for drying an object to be cleaned after cleaning,
Drying with hot air, that is, holding the object to be cleaned in a drying chamber filled with high-temperature air, and blowing high-temperature air onto the object to be cleaned causes heat transfer from the hot air to adhere to the object to be cleaned and the object to be cleaned. Generally, the cleaning solution is heated to evaporate and scatter the cleaning solution.However, it is difficult to evaporate the cleaning solution with deep bag holes or complicated shapes such as water-based or hydrocarbon-based cleaning agents. In the case of cleaning with hot air, it is difficult to completely dry the inside of the bag hole by hot air drying, so the drying temperature is increased or the drying time is increased.

Further, as a drying device other than the hot air drying, a vacuum drying device or a device which dries by replacing with a low boiling point substance such as isopropyl alcohol (IPA) is also employed.

[0004]

Although hot-air drying is simple, the object to be cleaned having a deep bag hole or a complicated shape is cleaned using a cleaning liquid such as a water-based or hydrocarbon-based cleaning agent which hardly evaporates. In this case, it is difficult to completely dry the inside of the bag hole, and it is necessary to raise the drying temperature or lengthen the drying time. When the drying temperature is raised, problems such as discoloration may occur depending on the material to be cleaned. Further, in order to lengthen the drying time, it is necessary to lengthen the tact time or lengthen the entire length of the washing / drying device.

For the object to be washed which is difficult to dry by hot air drying, vacuum drying or isopropyl alcohol (I
This can be improved by adopting substitution drying with a low boiling point substance such as PA), but in both cases, the apparatus becomes complicated as compared with hot air drying.
Furthermore, in the case of vacuum drying, since the drying chamber is evacuated each time after the object to be cleaned is introduced, the tact time becomes long, and the amount of heat required for evaporation after cleaning is efficiently transferred to the object to be cleaned in vacuum. There is a need. In addition, in the case of displacement drying, the number of substitution steps is increased, and when alcohols are used, measures to prevent ignition are required.

The object of the present invention is to improve the drying efficiency in hot air drying, so that it is possible to perform cleaning even on a deep bag hole or an object to be cleaned having a complicated shape, without raising the drying temperature or lengthening the drying time. It is to provide a hot air drying device that can completely dry the inside of the bag hole.

[0007]

A hot air drying apparatus according to the present invention holds an article to be cleaned in a drying chamber filled with high temperature air, and transfers heat from the high temperature air to the article to be cleaned and the article to be cleaned. In a hot-air drying device that heats the adhered cleaning liquid to evaporate and scatter the cleaning liquid, a nozzle header with multiple nozzle holes is equipped in the drying chamber, and compressed air is ejected from the nozzle holes to agitate the high-temperature air in the drying chamber. It is characterized by that.

By stirring the high temperature air in the drying chamber, the heat transfer coefficient to the object to be cleaned is increased, and effective drying is performed.

The compressed air ejected from the nozzle holes is preferably dry air.

Further, it is preferable to keep the distance from the nozzle hole to the object to be cleaned appropriately, and the distance from the nozzle hole to the object to be cleaned is 30 mm to 200 mm.

Furthermore, the nozzle header is moved in parallel,
It is preferable to perform swinging, rotating, or a combination thereof. As a result, the drying effect can be increased.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a hot air drying device according to the present invention will be described with reference to the drawings. In the following description, up, down, left and right mean up, down, left and right in the figure.

In FIG. 1, the hot-air drying device comprises a drying chamber (1) having a hot-air outlet (10) below, and a hot-air generating device (2) consisting of a blower (8) and a heater (9). , A compressed air device that generates compressed air and supplies it into the drying chamber (1)
(3) An air dryer (4), a pressure regulating valve (5), an air filter (6) and a nozzle header (11) are provided. The nozzle header (11) extends in the horizontal direction and has a plurality of nozzle holes (12) for blowing compressed air upward. The nozzle header (11) is arranged above the hot air outlet (10) and directly below the object to be cleaned (7).

The hot air supplied from the hot air generator (2) to the lower side of the drying chamber (1) gently blows out from the blowing port (10) to keep the air in the drying chamber (1) in a high temperature atmosphere. Drying room
The hot air in (1) is circulated, which
The capacity of the heater (9) is reduced and the energy consumption is reduced.

Compressed air is supplied from the compressed air device (3) to the nozzle header (11) via the air dryer (4), the pressure regulating valve (5) and the air filter (6), and is supplied at high speed from the nozzle hole (12). It blows into the drying chamber (1) and collides with the object to be cleaned (7) while entraining the high temperature air around it. As a result,
Hot air becomes turbulent around (7), increasing the heat transfer coefficient from the hot air to the object to be cleaned (7).
The heating and drying of (7) is promoted.

Here, any or all of the air dryer (4) and the pressure adjusting valve (5) and the filter (6) may be omitted, but the drying effect is enhanced and the inside of the drying chamber (1) is clean. In order to maintain the atmosphere, it is preferable to equip all of them.

In the example shown in FIG. 1, hot air is blown from below the drying chamber (1), and the nozzle header (11) is hot air blowing port.
It is located above (10) and directly below the item to be cleaned (7), but the placement of the hot air outlet and nozzle header is optional, and the size, number, direction, etc. of the nozzle holes as well as the item to be cleaned are It should be decided in consideration of the shape and size, especially the size and position of the bag hole, etc. and the arrangement of the object to be cleaned.

FIG. 2 shows the nozzle header (13) to be cleaned (7).
The nozzle header (13) extends in the vertical direction and has a plurality of nozzle holes (14) for ejecting compressed air inward. Such an arrangement is a bag hole where the object to be cleaned (7) opens horizontally.
It is effective when it has (7a). In addition,
In the description after FIG. 2, the same components as those in FIG.

In the hot air drying apparatus shown in FIGS. 1 and 2, the distance from the nozzle holes (12) and (14) to the object to be cleaned (7) is at least sufficient to enclose the surrounding high temperature air, and It is necessary to maintain the flow velocity of hot air even in the vicinity of the object to be cleaned (7).
To 200 mm. Also, the nozzle hole (12)
The flow rate of the compressed air ejected from (14) is preferably in the range of 10 to 20% of the total circulating hot air volume of the hot air drying device. Furthermore, it is preferable that the compressed air ejected from the nozzle holes (12) and (14) is dry air. By doing this, the hot air can be circulated and the humidity in the drying chamber (1) can be kept low, so it is not necessary to take in some fresh air from the outside to prevent the humidity in the drying chamber (1) from becoming too high. .

In the hot-air drying device shown in FIGS. 1 and 2, the nozzle headers (11) and (13) are fixed, but the nozzle header is constructed so that it can move in parallel, swing and rotate. May be done. By moving the nozzle header, the ejection direction and the distance to the object to be cleaned (7) are constantly changed, whereby any part of the object to be cleaned (7) is heated uniformly and the drying effect can be improved. 3 to 6 show a hot-air drying device provided with movable nozzle headers (15) (19) (24).

In the hot air drying apparatus shown in FIG. 3, the nozzle header (15) extends in the horizontal direction, has a plurality of nozzle holes (16) for blowing compressed air upward, and has a hot air blowing port (10). It is located above and below the object to be cleaned (7), and is vertically movable. The vertical movement of the nozzle header (15) is achieved by attaching the left end of the nozzle header (15) to the downward facing cylinder (17) provided on the left wall of the drying chamber (1). The flexible pipe (18) connects the filter (6) with the filter (6).

In the hot air drying device shown in FIG. 4, the nozzle header (19) extends in the horizontal direction and has a plurality of tubular nozzles (20) for blowing compressed air, and the hot air blowing port (1
It is located above (0) and below the object to be cleaned (7),
It is designed to be movable left and right. The nozzle (20) has its lower end attached to the nozzle header (19) and its upper end near the support member (23) arranged above the nozzle header (19) by pins, respectively. It is made possible to swing with the left and right movement of 19). Nozzle header
The lateral movement of (19) is achieved by attaching the right end of the nozzle header (19) to the left-facing cylinder (21) provided on the right wall of the drying chamber (1).
The flexible pipe (22) connects the filter (6) and the filter (6).

In the hot-air drying device shown in FIGS. 5 and 6, the hot-air outlets (27) are provided at predetermined intervals on the left and right sides of the drying chamber (1), and the nozzle header (24) is a flat surface. It is more cross-shaped as viewed from above, has a plurality of nozzle holes (25) for blowing compressed air upward, and is arranged directly below the object to be cleaned (7). A vertical pipe (26) communicating with the nozzle header (24) is connected to the center of the nozzle header (24), and the vertical pipe (26) is rotated around the vertical axis by a rotating device (28). By being rotated, the nozzle header (24)
Is rotated about the vertical axis.

In the hot air drying, the cleaning liquid adhered to the object to be cleaned (7) is heated directly by the high temperature air around the object to be cleaned (7) into droplets and indirectly heated through the object to be cleaned (7). It is heated and evaporates and scatters. The mechanism of direct heating is shown in FIG. 7, and the mechanism of indirect heating is shown in FIG.

In the direct heating shown in FIG. 7, deep bag holes (7
For the liquid droplets (71) remaining in a), the amount of heat transferred is small because the heat transfer area is small and the heat transfer coefficient is small in direct heating to the liquid droplets (71) (see FIG. (a)). Evaporation is limited from the surface of the droplet (71) (see FIG. (B)). Moreover, if the droplets (71) are left behind in the holes due to the progress of evaporation, the holes are filled with moist air (72) (humidity: 100%), which makes it difficult to evaporate (see FIG. (C)). ).

In the indirect heating shown in FIG. 8, since the heat transfer area is large, a large amount of heat is given to the droplet (71) (see FIG. (A)), and the droplet (71) in the bag hole (7a) is also heated. When heated, the air first dissolved in the liquid becomes bubbles (73) (see FIG. (B)), and the droplets (71) are pushed out and most of them are scattered (see FIG. (C)). The remaining droplets (71) adhere to the inner surface of the bag hole (7a) in the form of a thin film (74), which facilitates evaporation (see FIG. (D)).

As can be seen from the comparison between the direct heating and the indirect heating described above, when the droplets (71) in the deep bag hole (7a) are dried, the object to be cleaned (7) itself can be efficiently heated. It is important, and conventionally, high-speed hot air was blown onto the object to be cleaned (7). However, the conventional drying device has a drawback that a blower with a large air volume and a large air pressure is required, which makes the device large and expensive. On the other hand, in the drying device of the present invention, the nozzles (12) (14) (1
6) By injecting compressed air from (20) (25), the surrounding high temperature air is engulfed to create a high-speed hot air flow,
The same effect as when a blower with a large air volume and a large air pressure is adopted can be obtained.

[0028]

According to the hot air drying apparatus of the present invention, the heat transfer coefficient to the article to be cleaned is increased by stirring the high temperature air in the drying chamber, and effective drying is performed. Even when using a cleaning liquid that does not evaporate easily, such as water-based or hydrocarbon-based cleaning agents, objects to be cleaned that have different shapes can be cleaned by hot air drying without raising the drying temperature or extending the drying time. Can be completely dried up to the depths.

By making the compressed air ejected from the nozzle holes dry air, the humidity inside the dry room can be kept low without taking in fresh air from the outside so that the humidity inside the dry room does not become high.

Further, by setting the distance from the nozzle hole to the object to be cleaned to 30 mm to 200 mm, the compressed air entrains the high temperature air around it, and the flow velocity of the hot air is maintained near the object to be cleaned, which is more effective. Drying is performed.

Furthermore, the nozzle header is moved in parallel,
The drying effect can be further increased by performing swinging, rotating, or a combination thereof.

[Brief description of the drawings]

FIG. 1 is a front view showing a first embodiment of a hot air drying device according to the present invention.

FIG. 2 is a front view showing a second embodiment of the hot air drying device according to the present invention.

FIG. 3 is a front view showing a third embodiment of a hot air drying device according to the present invention.

FIG. 4 is a front view showing a fourth embodiment of a hot air drying device according to the present invention.

FIG. 5 is a front view showing a fifth embodiment of the hot air drying device according to the present invention.

FIG. 6 is a sectional view taken along the line VI-VI in FIG. 5;

FIG. 7 is an explanatory view of direct heating of droplets by hot air among drying mechanisms of droplets remaining in the bag hole of the object to be cleaned.

FIG. 8 is an explanatory diagram of indirect heating via the object to be cleaned among the drying mechanisms of the droplets remaining in the bag hole of the object to be cleaned.

[Explanation of symbols]

 (1) Drying chamber (7) Cleaning object (11) (13) (15) (19) (24) Nozzle header (12) (14) (16) (20) (25) Nozzle hole

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazuyuki Miyake 5-3-2, Nishikujo 5-chome, Konohana-ku, Osaka City Hitachi Shipbuilding Co., Ltd.

Claims (5)

[Claims] 1. An object to be cleaned (7) and an object to be cleaned are held in a drying chamber (1) filled with high temperature air after the cleaning, and heat is transferred from the high temperature air. In a hot air dryer that heats the cleaning liquid attached to (7) to evaporate and scatter the cleaning liquid, a large number of nozzle holes (12) (14) (16) (2) are provided in the drying chamber (1).
Equipped with nozzle headers (11) (13) (15) (19) (24) having 0) (25), compressed air is supplied from the nozzle holes (12) (14) (16) (20) (25). A hot-air drying device characterized by being jetted to agitate the hot air in the drying chamber (1). 2. The hot air dryer according to claim 1, wherein the compressed air ejected from the nozzle holes (12) (14) (16) (20) (25) is dry air. 3. The distance from the nozzle hole (12) (14) to the object to be cleaned is 30 mm to 200 mm.
Hot air dryer. 4. The hot air drying device according to claim 1, wherein the nozzle headers (15), (19) and (24) are caused to perform parallel movement, swing, rotation or a combination thereof. 5. The flow rate of the compressed air ejected from the nozzle holes (12) (14) (16) (20) (25) is in the range of 10 to 20% of the total circulating hot air volume of the hot air drying device. The hot air dryer according to claim 1.