WO2010050782A2

WO2010050782A2 - Filter assembly

Info

Publication number: WO2010050782A2
Application number: PCT/KR2009/006354
Authority: WO
Inventors: In-Tak Lee
Original assignee: Woongjin Coway Co., Ltd.
Priority date: 2008-10-31
Filing date: 2009-10-30
Publication date: 2010-05-06
Also published as: MY149265A; EP2361132A2; CN102202760A; KR20100048775A; CN102202760B; WO2010050782A3; KR101094803B1; EP2361132A4

Abstract

There is provided a filter assembly that can reduce the thickness of a filter housing and the weight of the filter assembly. A filter assembly may include: a filter housing having a hollow therein and a welding rib provided along a periphery of one side thereof; a filter member arranged inside the filter housing and filtering water flowing into the filter housing; and a housing cap having a welding recess in which the welding rib is inserted, the welding recess smaller than the welding rib so that the welding rib is welded to the welding groove as both sides of the welding rib are rubbed against both sides of the welding recess.

Description

FILTER ASSEMBLY

The present invention relates to a filter assembly.

In general, a water treatment apparatus filters water to remove heavy metals or foreign substances contained in the water. Examples of the water treatment apparatus may include a water purifier, a bidet, a humidifier, a dish washer, and a refrigerator having a water purification system.

At least one filter assembly may be installed in the water treatment apparatus in order to filter water. In the filter assembly, while a filter member is inserted into a filter housing, a housing cap may be welded to the filter housing. Here, the filter housing and the housing cap are separately manufactured using molds and are then welded together.

FIG. 7 is a view illustrating a coupled structure of a filter housing and a housing gap in a conventional filter assembly.

A welding recess 12 is formed in the outer periphery of one side of a filter housing 10. A welding rib 22 is formed along the outer periphery of a housing cap 20 so that the welding rib 22 is inserted into the welding recess 12. When the housing cap 20 is installed on one side of the filter housing 10, the welding rib 22 of the housing cap 20 corresponds to the welding recess 12 of the filter housing 10. When the housing cap 20 is rotated, the welding rib 22 and the welding groove 12 are rubbed together so that the welding rib 22 and the welding groove 12 are welded together.

However, in order to form the welding groove 12 and a structure (rib) around both sides of the welding groove 12, the filter housing 10 needs to have a minimum thickness, thereby increasing the thickness of the entire filter housing 10. Furthermore, as the thickness of the filter housing 10 increases, the weight, manufacturing costs and logistical costs of the filter assembly are significantly increased.

When external shocks are applied when the housing cap 20 is inserted into the filter housing 10, the welding rib 22 may be inserted into the welding recess 12 at an unusual position. This may cause a welding failure because the housing cap 20 is abnormally welded to the filter housing 10. When the housing cap 20 is supported by a jig on one side of the filter housing 10, incomplete welding may occur due to the tolerance of the jig.

Furthermore, the welding rib 22 has three surfaces, that is, side surfaces and an end surface, which increases welding time.

In addition, it is difficult to determine whether the filter housing and the housing cap are normally welded. Therefore, when a minute welding error occurs in the filter assembly, an additional test is conducted to determine whether a welding failure occurs or not, thereby reducing productivity and requiring additional equipment.

An aspect of the present invention provides a filter assembly that can improve productivity and reduce the thickness and weight of a filter housing by a new design of a welding portion.

An aspect of the present invention also provides a filter assembly that can minimize welding failures even when external shocks are applied or the tolerance of a jig occurs during a welding process.

An aspect of the present invention also provides a filter assembly that facilitates checking whether a welding failure has occurred in the filter assembly in a manufacturing process.

According to an aspect of the present invention, there is provided a filter assembly including: a filter housing having a hollow therein and a welding rib provided along a periphery of one side thereof; a filter member arranged inside the filter housing and filtering water flowing into the filter housing; and a housing cap having a welding recess in which the welding rib is inserted, the welding recess being smaller than the welding rib so that the welding rib is welded to the welding groove as both sides of the welding rib are rubbed against both sides of the welding recess.

Both sides of the welding rib may be tapered.

Both sides of the welding groove may be tapered so that the welding rib is slid and inserted into the welding groove in an exact welding position.

A guide portion may be provided along one end of the housing cap in order to prevent tolerance from occurring when the welding rib is inserted into the welding groove.

A welding depth determination portion may be provided along an outer surface of the filter housing so that the welding depth determination portion corresponds to an end of the guide portion when the housing cap and the filter housing are normally welded together.

A distance between an end of the filter housing and the welding depth determination portion may be greater than a distance between an opening of the welding groove of the filter housing cap and the end of the guide portion by a welding depth.

The welding depth determination portion may have a circular shape along a circumferential direction of the filter housing.

According to an aspect of the invention, the thickness and weight of a filter housing can be reduced.

According to an aspect of the invention, a welding failure can be minimized even when external shocks are applied or the tolerance of a jig occurs during a welding process.

According to an aspect of the invention, productivity can be improved by shortening the time required for a process of manufacturing a filter assembly as well as the time required for a process of manufacturing a filter housing.

According to an aspect of the invention, it can be checked during a manufacturing process whether a welding failure has occured in a filter assembly.

FIG. 1 is a perspective view illustrating a filter assembly according to an exemplary embodiment of the present invention.

FIG. 2 is an exploded sectional view illustrating the filter assembly of FIG. 1.

FIG. 3 is an exploded sectional view illustrating a welding structure of the filter housing and the housing cap, shown in FIG. 2.

FIG. 4 is a cross-sectional view illustrating a state in which one end of the filter housing of FIG. 2 is inserted into a guide portion of the housing cap.

FIG. 5 is a cross-sectional view illustrating a state in which the housing cap is inserted into the filter housing before the filter housing and the housing cap of FIG. 2 are welded together.

FIG. 6 is a cross-sectional view illustrating a state in which the housing cap is welded to the filter housing of FIG. 2.

A filter assembly according to exemplary embodiments of the present invention will now be described in detail.

FIG. 1 is a perspective view illustrating a filter assembly. FIG. 2 is an exploded sectional view illustrating the filter assembly of FIG. 1.

Referring to FIGS. 1 and 2, a filter assembly 100 includes a filter housing 110, a filter member 120 and a housing cap 130.

The filter housing 110 has a hollow therein. An inlet housing cap 111 may be formed integrally with the water inlet side of the filter housing 110. This filter housing 110 may have a cylindrical shape.

An inlet pipe 112 may protrude from the inlet housing cap 111 so as to be connected to a water pipe (not shown). A plurality of support ribs (not shown) may be formed in a radial manner inside the inlet housing cap 111. Therefore, water can pass between the support ribs.

The filter member 120 is detachably arranged in the filter housing 110. Here, an inlet cover 121 may be coupled to the end of the water inlet side of the filter member 120, while a discharge cover 125 may be coupled to the end of the water discharge side of the filter member 120.

The housing cap 130 is arranged at one end of the filter housing 110. A discharge pipe 131 may be formed at the center of the housing cap 130 so that the discharge pipe 131 is coupled to a discharge purification pipe (not shown).

The filter housing 110 and the housing cap 130 may be formed of various kinds of synthetic resins, such as polypropylene.

FIG. 3 is an exploded sectional view illustrating a welding structure of a filter housing and a housing cap.

Referring to FIG. 3, a welding rib 115 may be formed along the periphery of one end of the filter housing 110. Here, the inner and outer surfaces of the welding rib 115 are tapered in cross-section so that the welding rib 115 is wedge-shaped. The entire shape of the welding rib 115 may be a circular ring-shaped cross section.

As such, since the welding rib 115, having a relatively smaller width than the filter housing 110, is only formed on one end of the filter housing 110 without forming a welding recess and a structure (ribs formed in both sides of the welding recess) around the welding recess, the entire thickness of the filter housing 110 can be relatively reduced. Like the present invention, by forming the welding rib 115 on the filter housing 110, the thickness of the filter housing 110 can be reduced by approximately 30 to 50% as compared to the film assembly in the related art.

Both sides of the welding rib 115 may be tapered. The welding rib 115 may be wedge-shaped so that the thickness thereof decreases toward the end.

The welding recess 135 may be formed in the housing cap 130 so that the welding rib 115 of the filter housing 110 is inserted into the welding recess 135. Here, the entire shape of the welding recess 135 may have a circular ring cross section.

In addition, the welding recess 135 is smaller than the welding rib 115. Therefore, as the housing cap 130 is rotated and both sides of the welding rib 115 are rubbed against both sides of the welding recess 135, the welding rib 115 is welded to the welding recess 135. Here, the filter housing 110 is further placed into the housing cap 130 to a predetermined distance (hereinafter, referred to as "welding depth") as the welding rib 115 is melted when being welded.

Both sides of the welding recess 135 may be tapered. As both sides of the welding recess 135 are tapered, the welding recess 135 is wider toward the opening thereof. Here, the opening of the welding recess 135 may be rounded so that the welding rib 115 is smoothly guided into the welding recess 135.

Therefore, when the housing cap 130 is put into one end of the filter housing 110 with a jig, the welding rib 115 is slid along one or both sides of the welding recess 135, thereby arranging the housing cap 130 at the exact rotation position.

In addition, the housing cap 130 may be located at a slightly inclined position in the filter housing 110 when a small tolerance occurs in the jig, the rotation center of the housing cap 130 may not coincide with that of the filter housing 110. However, according to the present invention, the welding rib 115 of the filter housing 110 is slid along one or both sides of the welding recess 135, the rotation center of the housing cap 130 can be appropriately compensated.

Furthermore, since both sides of the welding recess 135 are tapered, and both sides of the welding rib 115 are tapered, even when the housing cap 130 is inserted at a slightly inclined position, the insertion of the housing cap 130 can be facilitated.

A guide portion 137 may be formed in one end of the housing cap 130 so that the filter housing 110 can be inserted into the housing cap 130 while the outer circumferential surface of the filter housing 110 makes contact with the guide portion 137. The guide portion 137 may have a cylindrical shape.

The guide portion 137 allows the housing cap 130 to be inserted into the filter housing 110 while the housing cap 130 is parallel with a longitudinal direction of the filter housing 110. Further, the guide portion 137 prevents the generation of tolerance when the welding rib 115 is inserted intothe welding recess 135.

Furthermore, a welding depth determination portion 117 may be formed on the outside of the filter housing 110 so that the welding depth determination portion 117 corresponds to the end of the guide portion 137 when the housing cap 130 and the filter housing 110 have been normally welded together.

A distance L1 between the end of filter housing 110 and the welding depth determination portion 117 may be longer than a distance L2 between the opening of the welding recess 135 of the housing cap 130 and the end of the guide portion 137 by the welding depth (L1>L2).

Therefore, it can be determined whether welding has been normally performed by checking whether the welding depth determination portion 117 corresponds to the end of the guide portion 137.

The welding depth determination portion 117 is formed along a circumferential direction of the filter housing 110. The welding depth determination portion 117 may have a circular shape. When the housing cap 130 is completely welded to the filter housing 110, it can be checked whether the filter housing 110 and the housing cap 130 are welded together by a normal welding depth by examining the filter housing 110.

A welding process of the filter assembly having the above-described configuration will now be described.

FIG. 4 is a cross-sectional view illustrating a state in which an end of a filter hosing is inserted into a guide portion of a housing cap.

Referring to FIG 4, after the filter member 120 is inserted into the filter housing 110, the filter housing 110 is raised using a jig, and the housing cap 130 is put on one end of the filter housing 110 with the use of the jig.

The guide portion 137 of the housing cap makes contact with and is inserted into the outer circumferential surface of one side of the filter housing 110. Here, the housing cap 130 may rarely be shaken because the housing cap 130 is guided by the guide portion 137 and may be inserted into the filter housing 110 in a direction nearly parallel with the longitudinal direction of the filter housing 110.

FIG. 5 is a cross-sectional view illustrating a state in which the housing cap is inserted into the filter housing before the filter housing and the housing cap are welded together.

Referring to FIG. 5, when the housing cap 130 is further inserted into the end of the filter housing 110, the welding rib 115 of the filter housing 110 is engaged in the welding recess 135 of the housing cap 130. Here, since both sides of the welding rib 115 and both sides of the welding recess 135 are tapered, the welding rib 115 of the filter housing 110 is accurately engaged in the welding recess 135 of the housing cap 130. Therefore, even when external shocks are applied to the filter housing 110 and the housing cap 130 or tolerance occurs, the welding rib 115 can be accurately inserted into the welding recess 135.

If the housing cap 130 rotates around the rotation center, the welding rib 115 of the housing cap 130 is rubbed against both sides of the welding recess 135. Since the welding rib 115 has a greater thickness than the welding recess 135, both sides of the welding rib 115 are rubbed against both sides of the welding recess 135.

FIG. 6 is a cross-sectional view illustrating a state in which a housing cap is welded to a filter housing.

Referring to FIG. 6, as the housing cap 130 continuously rotates, molten materials are generated on friction surfaces of the welding rib 115 and the welding recess 135 due to frictional heat therebetween. Here, the welding rib 115 is melted due to the frictional heat and is gradually reduced in size.

As the welding rib 115 is melted, the filter housing 110 enters the housing cap 130. Here, the molten material is created in greater profusion on the friction surfaces of the welding rib 115 and the welding recess 13.

When it is determined the predetermined welding time is up, the jig stops the operation of the housing cap 130.

When the housing cap 130 is stopped, both sides of the welding rib 115 and both sides of the welding recess 135 are welded together with the molten material. Here, the welding time can be shortened because the welding rib 115 has two welding surfaces (both side surfaces) compared to when the welding rib 115 has three welding surfaces (both side surfaces and end surface). Here, a portion in which the welding rib 115 and the welding recess 135 are welded together is denoted by reference numeral 138.

When the welding process of the filter assembly 100 is completed, it can be determined whether the end of the guide portion 137 corresponds to the welding depth determination portion 117.

When the end of the guide portion 137 generally corresponds to the welding depth determination portion 117, it is determined that filter assembly 100 has been normally welded.

On the other hand, when the end of the guide portion 137 partially corresponds to or does not completely correspond to the welding depth determination portion 117, it is determined that the welding process of the filter assembly 100 has not been performed in a normal manner.

As such, it is determined whether the filter assembly 100 is defective or not by checking whether the guide portion 137 and the welding depth determination portion 117 correspond to each other.

An aspect of the present invention can reduce the thickness and weight of a filter housing and allows checking in advance whether there is an error in a welding process of a filter assembly, thereby ensuring significant industrial applicability.

Claims

A filter assembly comprising:

a filter housing having a hollow therein and a welding rib provided along a periphery of one side thereof;

a filter member arranged inside the filter housing and filtering water flowing into the filter housing; and

a housing cap having a welding recess in which the welding rib is inserted, the welding recess being smaller than the welding rib so that the welding rib is welded to the welding groove as both sides of the welding rib are rubbed against both sides of the welding recess.
The filter assembly of claim 1, wherein both sides of the welding rib are tapered.
The filter assembly of claim 1, wherein both sides of the welding groove are tapered so that the welding rib is slid and inserted into the welding groove in an exact welding position.
The filter assembly of claim 1, wherein a guide portion is provided along one end of the housing cap in order to prevent tolerance from occurring when the welding rib is inserted into the welding groove.
The filter assembly of claim 4, wherein a welding depth determination portion is provided along an outer surface of the filter housing so that the welding depth determination portion corresponds to an end of the guide portion when the housing cap and the filter housing are normally welded together.
The filter assembly of claim 5, wherein a distance between an end of the filter housing and the welding depth determination portion is greater than a distance between an opening of the welding groove of the filter housing cap and the end of the guide portion by a welding depth.
The filter assembly of claim 5, wherein the welding depth determination portion has a circular shape along a circumferential direction of the filter housing.