Patent Publication Number: US-8528128-B2

Title: Closure device for drain pipeline

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a closure device for a drain pipeline and, more particularly, to a closure device suitable for mounting between a drain of a sink or washbasin and a drainpipe. 
     2. Description of the Related Art 
     The drain opening of a sink or washbasin is mostly installed with a drain to prevent sundries from flowing into a drainpipe of the sink or washbasin. However, the drain is not closed, and odor generated from dirt accumulated within the drainpipe will flow through the drain opening into an indoor space. In addition, pests such as cockroaches and mosquitoes might also climb into the indoor space through the drain, which might lead to the lowering of the environment hygiene quality of the indoor space. 
     The sink drain may be installed with a conventional closing device for blocking odor and pests. However, the sundries and residues in the discharged water are usually stopped by the closing device and get accumulated within the sink drain, leading to plugging of the pipeline. Further, cleaning of the sundries and residues in the closing device is always not easy. Furthermore, A U-shaped or S-shaped drain trap has been proposed for being mounted between the drain and the drainpipe of the sink or washbasin so that odor and pests can be prevented by the retained water in the U-shaped or S-shaped drain trap. However, if water is not discharged into the drain opening for a certain period of time, the water in the drain trap will get dried due to negative pressure in the drainpipe, and then the effect of blocking odor and pests will be lost. Further, it is troublesome to install the drain trap in existing drain pipelines. 
     BRIEF SUMMARY OF THE INVENTION 
     Thus, it is an objective of the present invention to solves this need and other problems in the field of blocking odor and pests in the pipeline by providing a closure device that is adapted to be installed between a drain of a sink or washbasin and a drainpipe so as to block the odor and the pests in the pipeline from flow into or entering the indoor space and to avoid the reverse flow of water in the drain pipeline. 
     To achieve the foregoing objective, a closure device of the present invention includes an outer sleeve, an inner sleeve mounted in the outer sleeve, and a closure member. The outer sleeve includes upper and lower ends spaced in a vertical direction. The upper end of the outer sleeve has an upper coupling opening for connecting with a drain of a sink or washbasin, and the lower end of the outer sleeve has a lower coupling opening for connecting with a drainpipe. The inner sleeve includes upper and lower sections spaced in the vertical direction. The upper section of the inner sleeve has an inner flange formed on an inner periphery of the upper section of the inner sleeve and defining a flow port. The inner sleeve is provided with a spring seat installed in the lower section of the inner sleeve, a guide extending from the spring seat toward the upper section of the inner sleeve in the vertical direction, and a spring mounted around the guide and including top and lower ends spaced in the vertical direction. The lower end of the spring abuts against the spring seat. The closure member is received in the inner sleeve and includes a closure portion and a tube portion extending upwards from the closure portion in the vertical direction. The closure portion is located between the spring seat and the inner flange of the inner sleeve and abuts against the upper end of the spring. The tube portion is mounted around an upper end of the guide. The closure member is moveable between a first position and a second position in the vertical direction. The spring biases the closure portion to close the flow port when the closure member is in the first position, and the closure portion is spaced from the inner flange to open the flow port when the closure member is in the second position. 
     In a preferred form, the closure device further includes a tubular lower connector having an upper end with an outer thread. The lower coupling opening of the outer sleeve has an inner thread, and the upper end of the lower connector is threadedly coupled with the lower coupling opening of the outer sleeve and abuts the lower section of the inner sleeve. The upper and lower sections of the inner sleeve are detachably coupled with each other to form the inner sleeve. The upper end of the outer sleeve includes an annular groove formed between an outer periphery of the upper end of the outer sleeve and the upper coupling opening of the outer sleeve. The upper section of the inner sleeve is engaged in the annular groove of the outer sleeve. 
     Preferably, the closure device further includes a tubular upper connector having a lower end with an outer thread. The upper coupling opening of the outer sleeve has an inner thread, and the lower end of the upper connector is threadedly coupled with the upper coupling opening of the outer sleeve. 
     The present invention will become clearer in light of the following detailed description of illustrative embodiments of this invention described in connection with the drawings. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
       The illustrative embodiments may best be described by reference to the accompanying drawings where: 
         FIG. 1  shows a perspective view of a closure device for a drain pipeline according to the preferred teachings of the present invention. 
         FIG. 2  shows an exploded, perspective view of the closure device of  FIG. 1 . 
         FIG. 3  shows a cross sectional view of the closure device of  FIG. 1  with the closure device mounted between a bottom of a sink drain and a drainpipe. 
         FIG. 4  shows a cross sectional view similar to  FIG. 3 , with a closure member of  FIG. 3  moved downwards to open a flow port. 
         FIG. 5  shows a cross sectional view of a closure device of another embodiment according to the preferred teachings of the present invention, with the closure device applied to a drainpipe of another type of sink. 
         FIG. 6  shows a cross sectional view similar to  FIG. 5 , with the closure device applied to a drainpipe of a washbasin. 
         FIG. 7  shows a cross sectional view similar to  FIG. 6 , with the closure device applied to a drainpipe of another type of washbasin. 
         FIG. 8  shows another cross sectional view similar to  FIG. 3 , with a lower connector fitted to a lower end of an outer sleeve. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     A closure device for a drain pipeline according to the preferred teachings of the present invention is shown in  FIGS. 1 through 4  of the drawings and generally designated  10 . The closure device  10  is adapted to be mounted between a bottom  14  of a sink drain  12  and a drainpipe  16 . Closure device  10  includes an outer sleeve  18 , an inner sleeve  20  mounted within outer sleeve  18 , and a closure member  22  received in the inner sleeve  20 . Outer sleeve  18  includes upper and lower ends  24  and  26  spaced in a vertical direction and a through-hole  28  extending from upper end  24  through lower end  26 . Through-hole  28  of outer sleeve  18  includes an upper coupling opening  30  formed in upper end  24  and a lower coupling opening  32  formed in lower end  26 . Upper and lower coupling openings  30  and  32  have inner thread  34  respectively. Upper coupling opening  30  is adapted to connect with the bottom  14  of sink drain  12 . The upper end  24  of outer sleeve  18  is provided with an annular groove  36  formed between an outer periphery of upper end  24  of outer sleeve  18  and upper coupling opening  30 . 
     Inner sleeve  20  includes upper and lower sections  38  and  40  spaced in the vertical direction and a through-hole  42  extending from upper section  38  through lower section  40 . A top end of upper section  38  of inner sleeve  20  is engaged in the annular groove  36  of outer sleeve  18 . According to the preferred form shown, each of upper and lower sections  38  and  40  is in the form of a sleeve body, and upper and lower sections  38  and  40  are detachably coupled with each other to form inner sleeve  20  so that closure member  22  can be easily installed within inner sleeve  20 . Moreover, an annular inner flange  44  is formed on an inner periphery of upper section  38  of inner sleeve  20  and defines a flow port  45  therein. According to the preferred form shown, inner flange  44  has conical cross sections. 
     Inner sleeve  20  is provided with a spring seat  46 , a guide  48 , and a spring  50 . Spring seat  46  is installed within lower section  40  of inner sleeve  20 . In this embodiment, spring seat  46  includes three spaced supports  52  each of which includes an outer end  54  engaged to a hole wall of through-hole  42  of lower section  40  and an inner end  56  located at a center axis of through-hole  42  (see  FIG. 4 ). The inner ends  56  of supports  52  are engaged together. Guide  48  extends from inner ends  56  of supports  52  towards upper section  38  of inner sleeve  20  in the vertical direction. According to the preferred form shown, guide  48  is a screw and includes a lower end  58  engaged to spring seat  46  and an upper end  60  located in upper section  38  of inner sleeve  20 . Spring  50  is mounted around guide  48  and includes an upper end  62  and a lower end  64  abutting against spring seat  46 . 
     According to the preferred form shown, closure member  22  includes a plate-shaped closure portion  66  and a tube portion  68  extends upwards from a top surface of closure portion  66 . Closure portion  66  is located between spring seat  46  and inner flange  44  of inner sleeve  20  in the vertical direction. Closure portion  66  has an outer diameter smaller than that of through-hole  42  but larger than that of flow port  45 . In assembly, closure member  22  is installed within lower section  40  of inner sleeve  20  first, and then upper section  38  of inner sleeve  20  is coupled to lower section  40  of inner sleeve  20 . Closure portion  66  abuts on upper end  62  of spring  50  such that closure member  22  is moveable up and down in inner sleeve  20  between a first position and a second position in the vertical direction. Tube portion  68  of closure member  22  is put on upper end  60  of guide  48  to guide the ascending and descending motion of closure member  22 . Closure portion  66  is biased by spring  50  to abut against a lower end of inner flange  44  so as to close flow port  45  when closure member  22  is in the first position, and closure portion  66  is spaced from inner flange  44  and compresses spring  50  to open flow port  45  when closure member  22  is in the second position. 
     According to the preferred form shown, closure device  10  further includes a tubular lower connector  70  having an upper end  72  with an outer thread and a lower end  74  with an inner thread. Upper end  72  of lower connector  70  is threadedly coupled with lower coupling opening  32  of outer sleeve  18  and abuts lower section  40  of inner sleeve  20  to position inner sleeve  20  in place. The lower end  74  of lower connector  70  is adapted to connect with drainpipe  16 . 
     In practice of closure device  10 , when water  76  is discharged into sink drain  12  (see  FIG. 4 ), the weight of water  76  will press closure member  22  downwards so that closure member  22  is moved to the second position to open flow port  45 , and water  76  can then be smoothly discharged into the drainpipe  16 . On the other hand, closure member  22  is biased by spring  50  and moved to the first position to close flow port  45  when there is no water  76  to be discharged into sink drain  12  (see  FIG. 3 ). Thus, flow port  45  is normally closed or sealed by closure member  22  to prevent flow of residual water in drainpipe  16  back into sink drain  12 , and the odor and pests such as cockroaches in drainpipe  16  can be prevented from flowing into or entering the indoor space. Further, When there are too much sundries accumulated in closure device  10  to affect the water drainage, the user can easily disassemble closure device  10  for cleaning purposes. 
       FIG. 5  shows that closure device  10  further includes a tubular upper connector  78  having an upper end  80  with an outer thread and a lower end  82  with an outer thread. Lower end  82  is threadedly coupled with upper coupling opening  30  of outer sleeve  18 , and upper end  80  is connected with a lower end  14  of drain  12  of another type of sink. 
       FIGS. 6 and 7  show that closure device  10  can be installed between drain  12  and drainpipe  16  of different types of washbasins, wherein upper connector  78  of closure device  10  is connected with washbasin drain  12 , and lower connector  70  is connected with washbasin drainpipe  16 . 
     It can be appreciated that the connection between lower connector  70  and lower end  26  of outer sleeve  18  is not limited to a thread connection.  FIG. 8  shows that lower connector  70  is fitted with lower end  26  of outer sleeve  18 . Alternatively, lower connector  70  can be integrally formed with lower end  26  of outer sleeve  18 . 
     Thus since the invention disclosed herein may be embodied in other specific forms without departing from the spirit or general characteristics thereof, some of which forms have been indicated, the embodiments described herein are to be considered in all respects illustrative and not restrictive. The scope of the invention is to be indicated by the appended claims, rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are intended to be embraced therein.