[0001] The present invention relates to an oil cut-off device for floor drains or similar,
wherein the floor drain comprises a liquid-containing member and a pipe member which
is directed down into liquid in said liquid-containing member such that a liquid seal
is defined, wherein the pipe member is adapted to guide liquid down to the liquid
seal, wherein the pipe member down below has an opening through which liquid can flow
out of said pipe member, wherein a valve seat for a valve body which is located in
the pipe member, is provided around the opening, wherein the valve body is provided
to float in liquids with higher density than liquid mixed with oil or oil, but sink
in liquids which are mixed with oil or consist of oil and thereby have a lower density
than the first mentioned liquids, wherein the valve body is provided to sink to the
valve seat and, in cooperation therewith, to close the opening and thereby interrupt
the flow of liquid through the floor drain and wherein at least one screening means
is provided in the pipe member, said screening means preventing liquid streams, which
flow down into the floor drain when the valve body floats in the liquid in the liquid
seal, from pressing said valve body in downwards direction to the valve seat.
[0002] Oil cut-off devices of the abovementioned type are already known from e.g. SE patent
specification 222 843. These oil cut-off devices are provided with screening means
which are mounted on a cover. However, screening means can only be used if the covers
are designed for holding them.
[0003] The object of the present invention has been to solve this problem and this is arrived
at according to the invention by providing the oil cut-off device defined above with
the characterizing features of claim 1.
[0004] By providing the screening means with legs which are adapted to engage lower, inwardly
directed wall portions of the pipe member, there is no need for covers which are designed
for holding the screening means.
[0005] The invention will be further described below with reference to the accompanying
drawings, wherein
fig. 1 is a vertical section of a floor drain having an oil cut-off device according
to the invention, whereby a valve body is situated in an upper opening position;
fig. 2 is a vertical section corresponding to fig. 1, whereby the valve body is situated
in a lower closing position;
fig. 3 is a section along the line III-III through the floor drain of fig. 2;
fig. 4 illustrates an enlarged part of the section of the floor drain according to
fig. 1; and
fig. 5 illustrates another enlarged part of the section of the floor drain according
to fig. 2.
[0006] The drawings illustrate a floor drain including an outer member 1 with an upper inlet
portion 2, a portion 3 located beneath said inlet portion for receiving and carrying
an insert and an outlet pipe 4 extending from said insert-carrying portion 3, said
outlet pipe 4 being connectable to a discharge system (not shown). The outlet pipe
4 is here directed laterally relative to the insert-carrying portion 3, but may alternatively
be directed downwards.
[0007] An insert 5 is removably located in the insert-carrying portion 3 of the floor drain.
This insert 5 includes a pipe member 6 which at the top has an outwardly directed
support flange 7 which is adapted to rest on inwardly directed support surfaces 8
on the outer member 1. At the top, the pipe member 6 also includes a sealing ring
9 which is in contact with downwardly directed surfaces 10 on the outer member 1,
so that a sealing is obtained between said outer member 1 and the insert 5. The sealing
ring 9 may assist in retaining the insert 5 at the outer member 1.
[0008] The upper portions of the pipe member 6 is provided with a number - preferably four
- of downwardly directed flanges 11 having holes 12, the purpose of which will be
described below.
[0009] The pipe member 6 includes downwardly directed wall portions 13 which down below
transform into lower, inwardly directed wall portions 14 with a centrally located
opening 15. The wall portions 14 define around the opening 15 an obliquely upwards/inwards
directed edge portion 16 with a softly rounded end edge 17. This edge portion 16 is
adapted to define a valve seat 18 on the pipe member 6.
[0010] The pipe member 6 further includes outer or external flange portions 19 - preferably
four flange portions - which extend along the downwardly directed and the inwardly
directed wall portions 13, 14. The flange portions 19 are inter alia adapted for centering
and for keeping the distance between the pipe member and a member 20 containing liquid.
The pipe member 6 is adapted to extend downwards into the liquid-containing member
20, which preferably consists of a trough with hook portions 21 - preferably four
- located at the top thereof. These hook portions 21 are adapted to permit snapping
of the liquid-containing member 20 onto the downwardly directed flanges 11 of the
pipe member 6 by bringing said hook portions 21 into engagement in the holes 12 of
said flanges 11.
[0011] The insert 5 functions so that liquid - normally water - flows down into the pipe
member 6 and gathers in the liquid-containing member 20 until it is filled. The liquid
surface 23 is then situated substantially above the lower, inwardly directed wall
portions 14 of the pipe member 6, i.e. the pipe member 6 extends far down into the
liquid-containing member 20, whereby a liquid seal 22 - normally called water seal
or odour or stench trap - is defined, which prevents odours in the discharge system
from rising through the floor drain.
[0012] If more liquid flows down into the pipe member 6 - after the liquid-containing member
20 is filled - liquid will flow over the upper edge 24 thereof and down into the outer
member 1 and through the outlet pipe 4 into the discharge system.
[0013] For preventing oil or liquids mixed with oil from flowing out through the floor drain,
the pipe member 6 includes a valve body 25 which is adapted to close the opening 15
in cooperation with the valve seat 18. This valve body 25 has such a density that
it floats in liquids having higher density than liquid mixed with oil or oil and that
it sinks in liquids mixed with oil or consisting of oil. The valve body 25 may e.g.
have a density of about 0,95 kg/dm
3, which means that it floats in water (with about one tenth above the surface) but
sinks in water mixed with oil or in oil, e.g. when fuel oils or Diesel oil flows down
into the floor drain.
[0014] When the valve body 25 sinks, it is brought in contact with the valve seat 18 so
that said valve body closes the opening 15 and thus, it is ensured that the liquid
mixed with oil or the oil can not flow out into the discharge system through the floor
drain.
[0015] The valve body 25 consists e.g. of a substantially cylindrical hollow body 26, which
down below is sealed or closed by an underside 27 and at the top by a cap 28.
[0016] The underside 27 has a downwardly directed retaining member 29 which is tubular in
shape and which has an outer or external seat 30 for a sealing ring 31. At the top
thereof, said sealing ring 31 engages the underside 27 and it is adapted to cooperate
down below with the seat 18 for closing the opening 15.
[0017] The inner space 32 of the valve body has an upwardly open member 33 into which a
weight 34 can be inserted from above. Lower portions of the upwardly open member 33
are situated in inner parts of the retaining member 29, so that the weight 34 can
be located as far below as possible in the valve body 25. This means that the valve
body 25 can be given a very low centre of gravity.
[0018] The upwardly open member 33 may be cylindrical and the weight 34 may be a cylindrical
body of metallic material.
[0019] The cylindrical hollow body 26 has at the top a seat 36 for a sealing ring 37 which
is adapted to provide a sealing between said cylindrical hollow body 26 and the cap
28. The cap 28 can preferably be snapped onto the cylindrical hollow body 26 so that
it can be removed when required for change of weight 34. Furthermore, the cylindrical
hollow body 26 has down below a lateral, outwardly directed guide flange 38 and the
cap 28 defines at the top another guide flange 39 by having a lateral, outwardly directed
shape.
[0020] The sealing ring 31 preferably consists of a soft material, which can be formed into
the rounded end edge 17 of the valve seat 18 and which also is capable of engaging
the valve seat 18 around contaminants adhering thereto. This sealing ring 31 may consist
of oil resistant cellular rubber material.
[0021] In the pipe member 6 there is provided a screening means 40 which is adapted to prevent
liquid streams 41, which from above flow down into the pipe member 6, from hitting
the valve body 25. Hereby, it is prevented that the valve body 25, when it floats
in liquid, is pressed down to the seat 18, and thus, there is no risk that the valve
body 25 unintentionally can interrupt the flow through the floor drain.
[0022] The screening means 40 preferably includes a cylindrical member 42 with a larger
diameter than the valve body 25. This cylindrical member 42 is open down below and
has an upper wall portion 43 with preferably a centrally located aeration opening
44 which is adapted to permit air (see arrow 45, fig. 1) to flow out of the screening
means 40 when liquid and the valve body 25 rise therein. The aeration opening 44 is
located so that the liquid streams 41 coming from above can not flow into the screening
means 40 from above to such an extent that they affect the valve body 25 in downwards
direction towards the valve seat 18. In order to prevent or obstruct the flow of liquid
streams 41 into the screening means 40, the aeration opening 44 may be screened off
from above by a casing or cover 46. This casing or cover 46 comprises. downwardly
directed mounting flanges 47 - preferably four such mounting flanges - which makes
it possible to snap the cover 46 onto a collar 48 which is provided extending upwards
from the upper wall portion 43 around the aeration opening 44.
[0023] The cover 46 is provided to define a laterally directed air slit 49 with the upper
wall portion 43 such that air 45 can flow out of the aeration opening 44 in a lateral
direction. The cover 46 is also provided such that lower parts of the air slit 49
lie on a level below the upper edge 50 of the collar 48.
[0024] The screening means 40 is removably mounted in the pipe member 6 and has outwardly
and downwardly directed support legs 51 - preferably four such support legs - which
down below are adapted to engage the lower, inwardly directed wall portions 14 of
said pipe member 6 so that said legs 51 determine the elevation of the screening means
40 in the pipe member 6. The support legs 51 are preferably also adapted to center
the screening means 40 relative to the pipe member 6.
[0025] The support legs 51 can form guide portions 52 for guiding the valve body 25 during
its movement between its upper position - in which it floats in the liquid - and its
lower position - in which it cooperates with the seat 18. Said guide portions 52 preferably
include members 53 which are located inside the screening means 40 and which may be
connected with the cylindrical member 42 as well as with the upper wall portion 43.
[0026] As is apparent from fig. 2, the screening means 40 is designed and located so that
it from above covers and receives the major part of the valve body 25 when said valve
body floats in the liquid in the liquid seal 22 so that the liquid streams 41 flowing
downwards pass said valve body 25 externally thereof in downwards direction towards
the opening 15, whereby liquid will flow out of the water seal 22 via the upper edge
24 of the liquid--containing member 20.
[0027] The invention is not limited to the embodiment described above and illustrated in
the drawings, but may vary within the scope of the following claims. As not specifically
described alternatives one should mention that the oil cut-off device may be used
in other types of floor drains than the type shown and it may also be used in roof
drains. The valve body 25 may be of another design than what is illustrated and the
screening means 40 may also be designed otherwise than what is shown and may also
consist of more than one member. The screening means 40 may e.g. be provided so that
upper portions thereof are located above the liquid surface 23 in the liquid seal
22, while lower portions thereof are located below said liquid surface 23. Furthermore,
the screening means 40 may be mounted so that its upper portions are situated in level
with upper portions of the pipe member 6 and it may be somewhat higher than half the
height of the pipe member 6. If there is an aeration opening 44 in the screening means
40, said opening 44 should preferably be located above the liquid surface 23 in the
liquid seal 22.
1. Oil cut-off device for floor drains or similar,
wherein the floor drain comprises a liquid-containing member (20) and a pipe member
(6) which is directed down into liquid in said liquid-containing member (20) such
that a liquid seal (22) is defined,
wherein the pipe member (6) is adapted to guide liquid down to the liquid seal (22),
wherein the pipe member (6) down below has an opening (15) through which liquid can
flow out of said pipe member (6),
wherein a valve seat (18) for a valve body (25) which is located in the pipe member
(6), is provided around the opening (15),
wherein the valve body (25) is provided to float in liquids with higher density than
liquid mixed with oil or oil, but sink in liquids which are mixed with oil or consist
of oil and thereby have a lower density than the firstmentioned liquids,
wherein the valve body (25) is provided to sink to the valve seat (18) and, in cooperation
therewith, to close the opening (15) and thereby interrupt the flow of liquid through
the floor drain, and
wherein at least one screening means (40) is provided in the pipe member (6), said
screening means (40) preventing liquid streams (41), which flow down into the floor
drain when the valve body (25) floats in the liquid in the liquid seal (22), from
pressing said valve body (25) in downwards direction to the valve seat (18),
characterized in
that the screening means (40) is removably positioned in the pipe member (6) and has outwardly
and downwardly directed support legs (51) which are adapted to engage lower, inwardly
directed wall portions (14) of said pipe member (6) for determining the elevation
of the screening means (40) in said pipe member (6).
2. Oil cut-off device according to claim 1, characterized in that the support legs (51) are adapted to center said screening means (40) relative to
said pipe member (6).
3. Oil cut-off device according to claim 1 or 2, characterized in that the support legs (51) define guide portions (52) for guiding the valve body (25)
during its movements in vertical direction between an upper position in which it floats
in liquid in the liquid seal (22) and a lower position in which it cooperates with
the seat (18).
4. Oil cut-off device according to claim 3, characterized in that the guide portions (52) cooperate with a lower lateral, outwardly directed, annular
guide flange (38) as well as an upper lateral, outwardly directed annular guide flange
(39) provided on a substantially cylindrical hollow body (26) of the valve body (25),
said cylindrical hollow body (26) being sealed or closed down below by an underside
(27) and at the top by a removable cap (28).
5. Oil cut-off device according to claim 4, characterized in that the upper lateral, outwardly directed annular guide flange (39) is defined by the
cap (28).
6. Oil cut-off device according to any of claim 4 or 5, characterized in that the cap (28) permits opening of the valve body (25) at the top thereof for removable
location of a weight (34) in lower portions of an inner space (32) in said valve body
(25), said weight being adapted to give said valve body (25) a predetermined weight.
7. Oil cut-off device according to claim 6, characterized in that the inner space (32) of the valve body (25) includes an in upwards direction open
member (33) which is designed to receive and position the weight (34) and that lower
portions of said upwardly open member (33) are situated in a retaining member (29)
which is directed downwards from an underside (27) of the valve body (25) and on which
a sealing ring (31) forming part of said valve body (25) is mounted externally, whereby
said valve body (25) attains a low centre of gravity.
8. Oil cut-off device according to claim 6 or 7, characterized in that the weight is a metal body (34).
9. Oil cut-off device according to any of claims 3-8, characterized in that the guide portions (52) include members (53) located inside the screening means (40).
10. Oil cut-off device according to any preceding claim, characterized in that the screening means (40) includes a cover (46) which from above screens off at least
one aeration opening (44) which is located at the top of said screening means (40)
and adapted to permit air (45) to flow out of said screening means (40) when the liquid
surface (23) in the liquid seal (22) and the valve body (25) rise in the screening
means (40), and that the cover (46) is located so that liquid streams (41) can not
flow into the screening means (40) through the aeration opening (44) to such an extent
that they press the valve body (25) in downwards direction to the valve seat (18).
11. Oil cut-off device according to claim 10, characterized in that the cover (46) is provided to define a laterally directed air slit (49) such that
air (45) can flow out through the aeration opening (44) in at least one lateral direction.
12. Oil cut-off device according to claim 11, characterized in that an upper wall portion (43) of the screening means (40) has an upwardly directed collar
(48) which is located around the aeration opening (44), that the cover (46) has downwardly
directed mounting flanges (47) through which said cover (46) can be snapped onto the
collar (48), and that the cover (46) is provided so that lower portions of the air
slit (49) are located at a level beneath an upper edge (50) of the collar (48).