FIELD OF THE INVENTION
[0001] The present invention relates to an interface for connecting an indoor floor to a
draining system, and more particularly to a self-sealing floor drain for draining
waste water smoothly and preventing sewage in a drain pipe from flowing back into
indoor floor.
BACKGROUND OF THE INVENTION
[0002] It is known that a floor drain is an important interface for connecting an indoor
floor to a draining system. One of the conventional floor drains is a so-called bell-type
floor drain, which generally includes an inverted bell-shaped drain basket and a strainer.
The drain basket of the conventional bell-type floor drain is easily removable from
the floor, and might by moved upward by a positive pressure in a drain pipe system
to destroy a water sealing effect of the floor drain, resulting in the invasion of
bad smell, hazardous gas, insects, and sewage from the drain pipe into a room via
the floor drain. To prevent the bad smell, hazardous gas, insects, and sewage from
entering into a room, self-sealing floor drains have been developed and received wide
acceptance. Fig. 1 shows a device preventing sewage from flowing backward disclosed
in
Chinese Patent No. 99801762.0. As shown, the device is a switch unit employing reverse water energy to achieve
upward and downward movements thereof. This switch unit includes a unique piston-like
structure to effectively solve the self-sealing problem in the conventional floor
drains. However, this switch unit also includes a weight, which offsets the opening
size of the switch unit under water pressure. Moreover, since the switch unit is located
at a center of the floor drain, it blocks a path via which waste water is drained
when the switch unit is moved upward, and inevitably lowers the draining speed. When
the amount of waste water is large, part of the waste water fails to pass through
the floor drain into the drain pipe and overflows the floor drain. Further, the switch
unit is driven to move upward and downward via meshed gears and rack, and therefore
involves in complicate structure and high manufacturing cost. Moreover, the weight
and the switch unit of the floor drain are mounted on a centered slide rod in the
drain basket. Large amount of waste water flows along the centered slide rod and permeates
into the weight and the switch unit, resulting in a switch unit working in an environment
containing waste water and thereby failing to work normally. That is, the device disclosed
in
Chinese Patent No. 99801762.0 limits the function of a floor drain and makes the floor drain unstable in performance.
SUMMARY OF THE INVENTION
[0003] A primary object of the present invention is to provide a self-sealing floor drain
to eliminate the drawbacks of unsmooth draining, complicate structure, high manufacturing
cost, and unstable function existed in the conventional floor drains.
[0004] To achieve the above and other objects, the self-sealing floor drain according to
the present invention includes a hollow cylindrical drain basket mounted in a drain
pipe or an existing bell-type floor drain, and a sealing disc movably mounted at a
water outlet of the drain basket. The drain basket has a case, on an inner wall surface
of which a switch unit is mounted. And, a torsion spring is provided in the switch
unit for opening and closing the sealing disc.
[0005] The self-sealing floor drain of the present invention has reasonable and simple structure
to enable lowered manufacturing cost, as well as convenient, stable, and safe use
thereof to allow smooth draining of waste water.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] The structure and the technical means adopted by the present invention to achieve
the above and other objects can be best understood by referring to the following detailed
description of the preferred embodiments and the accompanying drawings, wherein
Fig. 1 is a vertical sectional view of a conventional floor drain;
Fig. 2 is a vertical sectional view showing the structure of a self-sealing floor
drain according to a preferred embodiment of the present invention;
Fig. 3 is a vertical sectional view of a case of the self-sealing floor drain of Fig.
2;
Fig. 4 is a top view of Fig. 3;
Fig. 5 is a vertical sectional view of a switch unit for the self-sealing floor drain
of Fig. 2;
Fig. 6 is top view of Fig. 5;
Fig. 7 is a vertical sectional view of a torsion spring pull rod for the self-sealing
floor drain of Fig. 2; and
Fig. 8 is a top view of Fig. 7.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0007] Please refer to Figs. 2 to 8, in which a self-sealing floor drain according to a
preferred embodiment of the present invention is shown. The self-sealing floor drain
provided by the present invention may be independently mounted to a drain pipe or
be used with an existing bell-type floor drain. In the illustrated embodiment, the
self-sealing floor drain is used with an existing bell-type floor drain. As shown
in Fig. 2, the self-sealing floor drain according to the present invention includes
a drain basket 1, a connecting interface 2, and a sealing member 3. The drain basket
1 may be mounted to a drain pipe or be used with an existing bell-type floor drain.
The connecting interface 2 is externally mounted around the drain basket 1 for directly
connecting to the drain pipe or to the bell-type floor drain. The sealing member 3
is mounted around an outer side of the connecting interface 2 to provide a sealing
effect between the connecting interface 2 and an inner wall surface of the existing
bell-type floor drain or the drain pipe.
[0008] The drain basket 1 includes a case 11, a switch unit 12, and a sealing disc 13.
[0009] As shown in Figs. 3 and 4, the case 11 is a hollow cylinder having a radially outward
flange 111 integrally formed around a top water inlet thereof. The case 11 is formed
at a bottom with a water outlet. A sealed section 112 is downward extended from a
position slightly higher than the water outlet to a slightly radially inward projected
position. The sealed section 112 has curved upper and lower surfaces. The case 11
is provided on an inner sidewall surface 114 with an axially extended shallow recess
with two opposite slide grooves 113. The shallow recess may be formed at any place
on the inner sidewall surface 114 of the case 11. The two slide grooves 113 have a
triangular cross section. However, the slide grooves 113 may also be any other geometrical
cross section.
[0010] As can be seen from Figs. 5 and 6, the switch unit 12 is a hollow body having a trapezoid
vertical section and a substantially oblong cross section. The switch unit 12 has
a top surface 121 and a left end wall surface 122, both of them have a curved cross
section to prevent impurities and wastes, such as hair, in waste water from being
accumulated or trapped thereat to block water flown into the floor drain. The switch
unit 12 also has an open right end 124 and two sidewalls 125. Each of the two sidewalls
125 is integrally provided along an end adjacent to the open right end 124 with an
outward protruded edge 126, which has a cross section and size identical to that of
the slide groove 113 on the case 11. In the illustrated embodiment, the protruded
edges 126 have a triangular cross section. The switch unit 12 is installed in the
case 11 by inserting the protruded edges 126 into the slide grooves 113, so that the
protruded edges 126 and the slide grooves 113 are engaged with one another in the
manner of tight fitting. End surfaces of the sidewalls 125 and the protruded edges
126 of the switch unit 12 in contact with the case 11 also have a curved cross section
corresponding to the curved inner sidewall surface 114 of the case 11, so that the
switch unit 12 may be tight fitted to the case 11. Therefore, the switch unit 12 may
be tightly mounted to the case 11 via engagement of the protruded edges 126 with the
slide grooves 113, and axially slidable along the slide grooves 113. The switch unit
12 includes a bottom surface 123, on which a through hole 127 is formed. The bottom
surface 123 is integrally formed on an upper side thereof with a vertically extended
curved wall 128, which is concentric with the through hole 127 and has an inner diameter
the same as a diameter of the through hole 127. The curved wall 128 together with
the curved left end wall 122 of the switch unit 12 define an internal hollow guide
pipe 138, which is concentric with the through hole 127 and has an inner diameter
the same as the diameter of the through hole 127. Alternatively, the hollow guide
pipe 138 may be directly integrally formed on the bottom surface 123.
[0011] A cylindrical torsion spring pull rod 129 is provided in the hollow guide pipe 138.
As can be seen from Figs. 7 and 8, the torsion spring pull rod 129 is provided on
an outer wall surface with an axially extended groove 130 of any geometrical cross
section. In the illustrated embodiment, the groove 130 has a triangular cross section.
Meanwhile, the hollow guide pipe 138 is provided on an inner wall surface with an
axially extended rib 131 having a cross section corresponding to the groove 130. The
torsion spring pull rod 129 is mounted in the hollow guide pipe 138 by aligning and
engaging the groove 130 with the rib 131, such that the torsion spring pull rod 129
is guided by the rib 131 to slide in the hollow guide pipe 138 only in an axial direction.
A stopper 132 is provided near an upper end of the torsion spring pull rod 129 to
limit a distance by which the torsion spring pull rod 129 can be moved downward in
the hollow guide pipe 138. The torsion spring pull rod 129 is provided at a lower
end surface with an internally threaded hole 133, and at an upper end surface with
a hole 139 for a bar 140 to insert therein. A spring holding ring 134 is connected
to a top of the bar 140. The bar 140 may be integrally formed with or additionally
screwed to the torsion spring pull rod 129. The hollow guide pipe 138 is also integrally
formed on the outer wall surface with a spring seat 135, on a top center of which
a dent is provided. A torsion spring 136 is mounted in the switch unit 12 with two
ends separately movably connected to the spring holding ring 134 on the bar 140 and
the dent on the spring seat 135.
[0012] The sealing disc 13 is located at the bottom of the case 11 below the sealed section
112. The sealing disc 13 has an annular lower end surface flush with the bottom of
the case 11, and has a curved peripheral surface matching with the curved lower surface
of the sealed section 112. The curved peripheral surface of the sealing disc 13 effectively
prevents impurities and wastes in the waste water from staying around the sealing
disc 13 to adversely affect a sealed condition at a joint 137 between the sealing
disc 13 and the sealed section 112. The sealing disc 13 is provided with a through
hole, which is aligned with the threaded hole 133 on the lower end surface of the
torsion spring pull rod 129 when the switch unit 12 is mounted in the case 11. A screw
is extended through the through hole on the sealing disc 13 into the threaded hole
133 to fixedly connect the sealing disc 13 to the torsion spring pull rod 129.
[0013] The connecting interface 2 is a hollow cylindrical member externally mounted around
an upper part of the case 11 of the drain basket 1, so as to connect the drain basket
1 to the drain pipe or the existing bell-type floor drain. A first sealing ring 5
is mounted between the flange 111 of the case 11 and the connecting interface 2.
[0014] The sealing member 3 is an annular member externally mounted around the connecting
interface 2. A contact surface between the connecting interface 2 and the sealing
member 3 is sealed by an L-shaped second sealing ring 6. The second sealing ring 6
may be other suitable shape. The sealing member 3 is formed along an outer circumferential
surface with a semi-circular recess 31, in which an O-ring 8 is mounted. With the
sealing member 3, a good sealing effect is produced at the joint of the drain basket
1 and an inner wall surface of the drain pipe or the existing bell-type floor drain.
[0015] When the present invention is in use, waste water flown into the drain basket 1 applies
a downward force on the sealing disc 13. At this point, the torsion spring pull rod
129 is caused to move downward and open the joint 137, allowing the waste water to
flow into the drain pipe via the opened joint 137. When all the waste water has been
drained, the torsion spring 136 brings the pull rod 129 upward, and the sealing disc
13 is caused to move upward and seal the joint 137 again, so that sewage, bad smell,
hazardous gas, and insects are stopped from entering into a room via the floor drain
due to a positive pressure state in the drain pipe.
[0016] It is noted the switch unit 12 in the present invention is mounted to one side of
the drain basket 1. As compared with the existing floor drain having a sealing switch
unit mounted to a center of the drain basket, a hindrance from the switch unit 12
of the present invention to the waste water flowing through the drain basket 1 is
minimized, preventing an overflowed floor drain when there is a large amount of waste
water. Moreover, the present invention eliminates the problem of hair and other impurities
held to the switch unit. The switch unit 12 of the present invention also has simple
structure and reduced components to enable convenient, stable, and safe use thereof.
1. A self-sealing floor drain, comprising a drain basket mounted in a drain pipe or an
existing bell-type floor drain, and a sealing disc movably mounted at a water outlet
of said drain basket; said drain basket being a hollow cylinder having a case; said
self-sealing floor drain being characterized in that said case of said drain basket is provided on an inner wall surface with a switch
unit, and said switch unit is internally provided with a torsion spring for opening
and closing said sealing disc.
2. The self-sealing floor drain as claimed in claim 1, wherein said case of said drain
basket is provided on an inner sidewall surface with a pair of slide grooves, and
said switch unit is slidably mounted to said slide grooves.
3. The self-sealing floor drain as claimed in claim 2, wherein said switch unit is a
hollow body having a trapezoid vertical section and a substantially oblong cross section,
a top surface and a left end wall surface, both of which have a curved cross section,
an open right end, two sidewalls, and a bottom surface; each of said two sidewalls
being integrally provided along an end adjacent to said open right end with an outward
protruded edge, said protruded edges having a cross section and size identical to
that of said slide grooves on said case of said drain basket, so that said protruded
edges may be inserted into said slide grooves; and said bottom surface of said switch
unit being formed with a through hole.
4. The self-sealing floor drain as claimed in claim 3, wherein end surfaces of said sidewalls
and said protruded edges of said switch unit in contact with said case have a curved
cross section corresponding to that of the inner sidewall surface of said case.
5. The self-sealing floor drain as claimed in claim 4, wherein said bottom surface of
said switch unit is integrally formed on an upper side thereof with a vertically extended
hollow guide pipe, which is concentric with said through hole on said bottom surface
and has an inner diameter the same as a diameter of said through hole; said hollow
guide pipe having a cylindrical torsion spring pull rod provided therein; said torsion
spring pull rod being provided on an outer wall surface with an axially extended groove,
and said hollow guide pipe being provided on an inner wall surface with an axially
extended rib corresponding to and received in said groove on said torsion spring pull
rod.
6. The self-sealing floor drain as claimed in claim 5, wherein said torsion spring pull
rod is provided near an upper end with a stopper to limit a distance by which said
torsion spring pull rod can be moved downward in said hollow guide pipe; said torsion
spring pull rod being provided at a lower end surface with an internally threaded
hole, and at an upper end surface with a hole for a bar to insert therein, and said
bar having a spring holding ring connected to a top thereof; said hollow guide pipe
being also integrally formed on the outer wall surface with a spring seat, on a top
center of which a dent is provided; and the torsion spring being mounted in said switch
unit with two ends separately movably connected to said spring holding ring on said
bar and said dent on said spring seat.
7. The self-sealing floor drain as claimed in any one of claims 1 to 6, wherein said
drain basket includes a sealed section downward extended from a position slightly
higher than the water outlet of said case to a slightly radially inward projected
position, and said sealed section having curved upper and lower surfaces; said sealing
disc having a curved peripheral surface matching with the curved lower surface of
said sealed section; said sealing disc being provided with a through hole, which is
aligned with said threaded hole on the lower end surface of said torsion spring pull
rod, such that a screw may be extended through said through hole on said sealing disc
into said threaded hole on said torsion spring pull rod to fixedly connect said sealing
disc to said torsion spring pull rod.
8. The self-sealing floor drain as claimed in claim 7, wherein said case of said drain
basket has a radially outward flange integrally formed around a top water inlet of
said drain basket.
9. The self-sealing floor drain as claimed in claim 8, further comprising a connecting
interface externally mounted around said case of said drain basket; said connecting
interface being a hollow cylindrical member for connecting said drain basket to the
drain pipe or the existing bell-type floor drain; and a first sealing ring being mounted
between said flange of said case and said connecting interface.
10. The self-sealing floor drain as claimed in claim 9, further comprising an annular
sealing member externally mounted around said connecting interface; and a contact
surface between said connecting interface and said sealing member being sealed by
an L-shaped second sealing ring; and said sealing member being formed along an outer
circumferential surface with a semi-circular recess, in which an O-ring is mounted.