Air curtain device and method for manufacturing the same

A method for manufacturing an air curtain device includes steps of: a) providing a frame that includes two side wall bodies and two end wall bodies cooperatively defining an inner space thereamong, and an upper opening and a lower opening through which the inner space communicates with the external environment; b) covering an upper surface and a lateral outer surface of the frame with a first covering layer; c) closing the lower opening by placing an air-permeable plate; d) sealing a gap between the air-permeable plate and the frame by a first adhesive; e) removing a portion of the first covering layer that covers the upper surface of the frame; and f) closing the upper opening by a cover that is sealingly connected to the frame.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to Taiwanese Invention Patent Application No. 109125598, filed on Jul. 29, 2020.

FIELD

The disclosure relates to an air curtain device and a method for manufacturing the same, and more particularly to an air curtain device from which air is prevented from leaking, and a method for manufacturing the same.

BACKGROUND

A conventional air curtain device includes a frame that has an upper opening and a lower opening spaced apart from each other in an up-down direction, a cover and an air-permeable plate. Specifically, the frame is formed by two side wall members that are spaced apart from each other, and two end wall members that interconnect the side wall members. The side wall members cooperate with the end wall members to define an inner space thereamong. The inner space communicates with the external environment through the upper opening and the lower opening. The cover and the air-permeable plate respectively cover the upper opening and the lower opening. When the conventional air curtain device is in operation, clean air is fed into the inner space to increase air pressure in the conventional air curtain device. When the air pressure is high enough, the conventional air curtain device produces a laminar airflow.

However, in a conventional method for manufacturing the conventional air curtain device, each of the end wall members is connected to the side wall members only by an adhesive, and the air-permeable plate is adhered to each of the end wall members and the side wall members to cover the lower opening by the adhesive as well. Consequently, the air pressure in the conventional air curtain device that the frame can withstand may be relatively low, which may easily cause air leakage through the frame. With the conventional method, strength of the frame can only be increased by applying more adhesive, and the adhesive may be likely to be over-applied. When the adhesive is over-applied during the assembling of the frame and the air-permeable plate, appearance of the conventional air curtain device may be affected, and the subsequent assembly of the frame and the cover may not be well-executed due to the excessive adhesive used.

SUMMARY

Therefore, an object of the disclosure is to provide a method for manufacturing an air curtain device that can alleviate at least one of the drawbacks of the prior art.

According to the disclosure, the method for manufacturing the air curtain device includes steps of: a) providing a frame that includes two side wall bodies spaced apart from each other, and two end wall bodies interconnecting the side wall bodies and cooperating with the side wall bodies to define an inner space thereamong, upper edges of the side wall bodies and the end wall bodies cooperatively forming a first connecting section, lower edges of the side wall bodies and the end wall bodies cooperatively forming a second connecting section, the first connecting section and the second connecting section respectively defining an upper opening and a lower opening through which the inner space communicates with the external environment; b) covering an upper surface and a lateral outer surface of each of the side wall bodies and the end wall bodies with a first covering layer; c) closing the lower opening of the frame by placing an air-permeable plate that abuts against a surface of the second connecting section facing the inner space, the air-permeable plate having a plurality of pores to thereby be air permeable; d) sealing a gap between the air-permeable plate and the second connecting section of the frame by a first adhesive; e) removing a portion of the first covering layer that covers the upper surface of each of the side wall bodies and the end wall bodies; and f) closing the upper opening of the frame by a cover that is sealingly connected to the first connecting section of the frame.

Another object of the disclosure is to provide an air curtain device that can alleviate at least one of the drawbacks of the prior art.

According to the disclosure, the air curtain device includes a frame, an air-permeable plate, a cover, a first adhesive and at least one gas fitting. The frame includes two side wall bodies and two end wall bodies. The side wall bodies are spaced apart from each other. The end wall bodies interconnect the side wall bodies, and cooperate with the side wall bodies to define an inner space thereamong. Upper edges of the side wall bodies and the end wall bodies cooperatively form a first connecting section. Lower edges of the side wall bodies and the end wall bodies cooperatively form a second connecting section. The first connecting section and the second connecting section respectively define an upper opening and a lower opening through which the inner space communicates with the external environment. The frame is formed by a base frame member having a base protruding part that surrounds the inner space and that protrudes upwardly, and a plurality of plate members. Each of the plate members is indented with abase-connecting recess, is located over the base frame member, and is coupled to the base protruding part by the base-connecting recess thereof. The base frame member and the plate members cooperatively define the side wall bodies and the end wall bodies. The air-permeable plate abuts against a surface of the second connecting section of the frame facing the inner space, and closes the lower opening. The air-permeable plate has a plurality of pores to thereby be air permeable. The cover is sealingly connected to the first connecting section of the frame to thereby close the upper opening of the frame. One of the frame and the cover is formed with at least one inlet opening through which the inner space of the frame communicates with the external environment. The first adhesive is applied to a gap between the air-permeable plate and the second connecting section of the frame, to a junction between the base frame member and each of the plate members, and to a junction between any adjacent ones of the plate members. The at least one gas fitting is connected to the at least one inlet opening of the one of the frame and the cover.

DETAILED DESCRIPTION

Before the disclosure is described in greater detail, it should be noted that, directional terms, such as “vertical,” “horizontal,” “upper,” “lower,” “inner,” “inwardly,” “outer,” “outwardly,” “front,” “rear,” “left,” “right,” “top” and “bottom,” may be used to assist in describing the disclosure based on the orientation of the embodiment shown in the illustrations. The use of these directional definitions should not be interpreted to limit the disclosure in any way.

Referring toFIGS.1to4, an embodiment of an air curtain device100according to the disclosure includes a frame1, an air-permeable plate2, a cover3, a first adhesive4a, a second adhesive4b, two gas fittings5and a plurality of screwing members6.

The frame1includes two side wall bodies12and two end wall bodies13. The side wall bodies12are spaced apart from each other. The end wall bodies13interconnect the side wall bodies12and cooperate with the side wall bodies12to define an inner space11thereamong. Upper edges of the side wall bodies12and the end wall bodies13cooperatively form a first connecting section14extending inwardly. Lower edges of the side wall bodies12and the end wall bodies13cooperatively form a second connecting section15extending inwardly. The first connecting section14and the second connecting section15respectively define an upper opening141and a lower opening151through which the inner space11communicates with the external environment. Each of the side wall bodies12and the end wall bodies13has an upper surface and a lateral outer surface that are opposite to (i.e., that face away from) the inner space11. The upper surfaces of the side wall bodies12and the end wall bodies13cooperatively form an upper surface of the first connecting section14that is opposite to the inner space11. Specifically, in this embodiment, the frame1is formed by an annular base frame member16and a plurality of plate members17. The base frame member16has a base protruding part161surrounding the inner space11and protruding upwardly. Each of the plate members17is indented with a base-connecting recess171, is located over the base frame member16, and is coupled to the base protruding part161by the base-connecting recess171thereof. Adjacent ones of the plate members17are connected to each other. The base frame member16and the plate members17cooperatively define the side wall bodies12and the end wall bodies13. It is noted that, in this embodiment, the frame1is formed by four plate members17. Two of the plate members17cooperate with the base frame member16to respectively define the side wall bodies12, and the other two of the plate members17cooperate with the base frame member16to respectively define the end wall bodies13. However, in certain embodiments, the frame1may be formed by, but not limited to, two plate members17. In one embodiment where the frame1is formed by two plate members17, one of the plate members17may cooperate with the base frame member16to define the end wall bodies13and one of the side wall bodies12, and the other one of the plate members17may cooperate with the base frame member16to define the other one of the side wall bodies12. The configurations of the base frame member16and the plate members17are not limited to those mentioned above. Moreover, the base frame member16and the plate members17may be integrated into a single piece.

The air-permeable plate2abuts against a surface of the second connecting section15of the frame1facing the inner space11, and closes the lower opening151of the frame1. The air-permeable plate2has a plurality of pores22(not shown) to thereby be air permeable. Specifically, the thickness of the air-permeable plate2ranges from 3 to 10 millimeters. The air-permeable plate2may be made from a sintered polymer material that is hydrophobic and that has moisture absorption of less than 5% (by mass). The sintered polymer material may be ultra-high-molecular-weight polyethylene (UHMWPE) that is resistant to corrosion and chemicals, and that has relatively high toughness, high impact resistance, low coefficient of friction and low moisture absorption among thermoplastic materials. Furthermore, the diameter of each of the pores22ranges from 0.01 to 100 micrometers. In one embodiment, the thickness of the air-permeable plate is 5 millimeters.

The cover3is sealingly connected to the first connecting section14of the frame1to thereby close the upper opening141of the frame1. Specifically, the first connecting section14of the frame1is indented with a groove142surrounding the upper opening141of the frame1, and is formed with a plurality of threaded holes143. The cover3has an annular protrusion31protruding from a bottom surface thereof and coupled to the groove142, is formed with a plurality of through holes32respectively corresponding in position to the threaded holes143, and has a lateral surrounding surface surrounding the through holes32.

The first adhesive4ais applied to a gap between the air-permeable plate2and the second connecting section15of the frame1, to a junction between the base frame member16of the frame1and each of the plate members17of the frame1, and to a junction between any adjacent ones of the plate members17. Preferably, the first adhesive4ais applied to an inner side of each of the side wall bodies12and the end wall bodies13opposite to the lateral outer surface thereof. The second adhesive4bis applied to the groove142of the first connecting section14of the frame1. The screwing members6respectively extend through the through holes32of the cover3, and respectively and threadedly engage the threaded holes143of the first connecting section14, so that the cover3and the first connecting section14are sealingly connected by the second adhesive4band the upper opening141of the frame1is closed.

In this embodiment, one of the plate members17of the frame1is formed with two inlet openings172through which the inner space11of the frame1communicates with the external environment. The gas fittings5are respectively connected to the inlet openings172. It is noted that, in certain embodiments, the frame1may be formed with only one inlet opening172, or more than two inlet openings172, and the air curtain device100may include only one gas fitting5, or more than two gas fittings5. The location of the frame1at which the inlet opening172is formed is not limited. In addition, in certain embodiments, the inlet opening172may be formed at the cover3.

When the air curtain device100is in operation, clean air (e.g., compressed dry air (CDA) or noble gases) is fed into the inner space11of the frame1through the gas fittings5. Because of the small diameter of the pores22, the clean air is not able to flow through the air-permeable plate2until the air pressure in the inner space11is high enough. When the increasing air pressure reaches the maximum static pressure, the pressure difference between the inner space11and the external environment urges the clean air to flow downwardly through the pores22of the air-permeable plate2. Therefore, a uniform air stream (i.e., an air curtain) (not shown) is generated. By virtue of the first adhesive4aand the second adhesive4b, the clean air is prevented from leaking out of the air curtain device100through the junctions between the frame1and the air-permeable plate2, between the frame1and the cover3, and between the frame1and each of the gas fittings5. The air-permeable plate2further has a zigzag-shaped structure21(seeFIG.3) at an edge thereof. The zigzag-shaped structure21has serrations substantially forming a zigzag pattern. The air-permeable plate2abuts against the surface of the second connecting section15facing the inner space11with the zigzag-shaped structure21thereof when the first adhesive4ais applied to the gap between the air-permeable plate2and the second connecting section15. By virtue of the serrations of the zigzag-shaped structure21, the area of contact between the first adhesive4aand the air-permeable plate2is larger than that between the first adhesive4aand an air-permeable plate with a uniformly straight edge, so that the air-permeable plate2is firmly connected to the frame1by the first adhesive4awith an airtight fit. Moreover, in addition to the connection formed by the first adhesive4a, the plate members17are each coupled to the base frame member16to cooperatively define the side wall bodies12and the end wall bodies13of the frame1. The coupling strengthens the frame1and prevents the clean air from leaking out of the air curtain device100through the frame1.

Referring toFIGS.5A and5B, an embodiment of a method for manufacturing an air curtain device100according to the disclosure includes steps S1to S8. Referring further toFIG.6, in step S1, the frame1is provided.

Referring further toFIG.7, in executing step S2, the upper surface and the lateral outer surface of each of the side wall bodies12and the end wall bodies13of the frame1are covered with a first covering layer7. Specifically, the first covering layer7may be a masking tape. In this embodiment of the method, the first covering layer7completely covers the upper surfaces and the lateral outer surfaces of the side wall bodies12and the end wall bodies13, and the groove142of the first connecting section14of the frame1, but in certain embodiments, the first covering layer7may only cover a portion of the upper surfaces and the lateral outer surfaces from which the excess first adhesive4ais more likely to come out when the first adhesive4ais accidentally over-applied.

Referring further toFIG.8, in executing step S3, the air-permeable plate2is placed in the inner space11of the frame1to close the lower opening151(seeFIG.2) of the frame1.

Referring further toFIG.9, in executing step S4, the gap between the air-permeable plate2and the second connecting section15of the frame1is sealed by the first adhesive4a. In this embodiment, the junction between the base frame member16of the frame1and each of the plate members17of the frame1, and the junction between any adjacent ones of the plate members17are sealed by the first adhesive4aas well. In addition, a fixture (not shown) that holds the base frame member16and the plate members17, by clamping the first connecting section14and the second connecting section15of the frame1, may be deployed before the application of the first adhesive4ato facilitate the application. It is noted that, for certain embodiments in which the base frame member16and the plate members17are integrated as one piece, the first adhesive4ais only applied to the gap between the air-permeable plate2and the second connecting section15.

Referring further toFIG.10, in executing step S5, a portion of the first covering layer7that covers the upper surface of each of the side wall bodies12and the end wall bodies13, and a portion of the first covering layer7that covers the groove142of the first connecting section14of the frame1are removed.

Referring further toFIG.11, in executing step S6, the gas fittings5are respectively connected to the inlet openings172of the frame1. Since the inlet openings172are formed at the frame1in this embodiment, portions of the first covering layer7that respectively cover the inlet openings172are removed right before step S6to thereby allow the connection. However, for certain embodiments in which the inlet openings172are formed at the cover3, the removal is not required because the first covering layer7does not cover the inlet openings172. After the gas fittings5are respectively connected to the inlet openings172, the cover3and the first connecting section14of the frame1may be temporarily assembled, and compressed dry air may be provided into the inner space11of the frame1through the gas fittings5to conduct an air tightness testing of the connection between the frame1and the air-permeable plate2.

Referring further toFIGS.12and13, in executing step S7, the cover3is sealingly connected to the first connecting section14of the frame1to close the upper opening141of the frame1. Specifically, step S7includes sub-steps S71to S74(seeFIG.5B). In executing sub-step S71, the second adhesive4bis applied to the groove142of the first connecting section14. It is noted that, in one embodiment, the second adhesive4bmay be flush with the upper surface of the first connecting section14. In executing sub-step S72, the lateral surrounding surface of the cover3is covered with the second covering layer8. Then, in executing sub-step S73, the annular protrusion31of the cover3and the groove142of the first connecting section14are coupled (seeFIG.4). Afterwards, the cover3is fastened to the first connecting section14by the screwing members6so that the cover3and the first connecting section14are sealingly connected by the adhesive4and the upper opening141of the frame1is closed.

Referring further toFIG.14, in executing step S8, the second covering layer8that covers the cover3, and the remaining portion of the first covering layer7that covers the lateral outer surface of each of the side wall bodies12and the end wall bodies13are removed. After that, the air curtain device100may be cleaned and then may be ready for product inspection.

In summary, by virtue of the first covering layer7covering the upper surface and the lateral outer surface of each of the side wall bodies12and the end wall bodies13, and the groove142of the first connecting section14of the frame1, and by virtue of the second covering layer8covering the lateral surrounding surface of the cover3, when the first adhesive4aand the second adhesive4bare accidentally over-applied, the excess first adhesive4aand the excess second adhesive4bare prevented from coming out to the upper surfaces and the lateral outer surfaces of the side wall bodies12and the end wall bodies13and to the lateral surrounding surface of the cover3. Therefore, an appearance of the air curtain device100is not affected by the application of the first adhesive4aand the second adhesive4b, and step S7in which the cover3is sealingly connected to the frame1may be well-executed. Moreover, by virtue of the base frame member16and the plate members17cooperatively forming the frame1, the strength of the structure of the air curtain device100is reinforced, and air leakage through the frame1is prevented.