BACKGROUND OF THE INVENTION
1. Field of the Invention
[0001] The invention relates to a sanitary fitting comprising
- a) a housing base having a contact surface;
- b) a mounting stud bolt configured to be inserted into a mounting through hole of
a sanitary installation, wherein the mounting stud bolt is arranged eccentrically
with respect to the contact surface at the housing base;
- c) a sealing gasket configured to be interposed between the contact surface of the
housing base and a support surface around the mounting through hole;
- d) a retaining element configured to be fastened on the mounting stud bolt on a side
of mounting through hole of the sanitary installation opposite to the housing base
in order to fasten the sanitary fitting at the sanitary installation.
[0002] The invention further relates to a sealing gasket for a sanitary fitting, wherein
the sealing gasket is configured to be interposed between a contact surface of a housing
base of the sanitary fitting and a support surface around a mounting through hole
of a sanitary installation.
2. Description of the Prior Art
[0003] A sanitary fitting usually comprises water connections protruding from a housing
base of the sanitary fitting for connection of the sanitary fitting to the domestic
plumbing lines. Furthermore such a sanitary fitting comprises a mounting stud bolt,
which has a male screw thread and protrudes from the housing base for mounting purposes.
[0004] During the installation of such a sanitary fitting, the mounting stud bolt and the
water connections are inserted into a through hole of a sanitary installation like
e.g. a washing table, a washbasin, a washstand, a wall installation or a pedestal
installation. In a next step, a retaining element is fastened on the mounting stud
bolt on the opposite side of the mounting through hole. Due to the fastening of the
retaining element a contact surface of the housing base is pressed against a support
surface around the mounting through hole and the sanitary fitting gets fixed at the
sanitary installation.
[0005] In order to prevent splash water from flowing in between the contact surface of the
sanitary fitting and the support surface of the sanitary installation and onward through
the mounting through hole a sealing gasket is interposed between the contact surface
and the support surface. Such a sealing gasket also compensates for any unevenness
of the support surface of the sanitary installation which is necessary because the
sanitary installations are usually made of ceramics having a rather undefined surface
flatness.
[0006] The sealing gaskets used for this purpose are usually rotationally symmetric rings
or the like. However, it turned out that it is sometimes difficult to properly fix
the sanitary fitting using such rotationally symmetric sealing gaskets.
SUMMARY OF THE INVENTION
[0007] It is therefore an object of the present invention to provide a sanitary fitting
and a corresponding sealing gasket which allows a better fastening of the sanitary
fitting. In particular, it is an object of the invention to provide a way to more
uniformly distribute the forces exerted on the sealing gasket throughout the fastening
of the retaining element.
[0008] This object is achieved by a sanitary fitting as mentioned in the beginning, wherein
e) the sealing gasket is asymmetric such that a first part of the sealing gasket yields
to a lesser extent than a second part of the sealing gasket under the load of forces
exerted by the contact surface and the support surface on the sealing gasket when
the retaining element is fastened on the mounting stud bolt.
[0009] The inventor has realized that the mounting stud bolt is usually arranged eccentric
with respect to the contact surface of the housing base in order to provide sufficient
space for the connection of the water connections inside the housing base. However,
due to the eccentric arrangement of the mounting stud bolt the distribution of forces
exerted on the sealing gasket between the contact surface and the support is imbalanced,
because the distribution of the exerted forces is defined by a system of lever arms
of different lengths. Therefore, the part of the sealing gasket contacting the side
of the housing base corresponding to the shorter lever arm (usually the side pointing
to the backside of the sanitary fitting) is compressed stronger than the remaining
part corresponding to the longer lever arm. Accordingly, the sanitary fitting tilts
to the side of the short lever arm and the housing base finally contacts the sanitary
installation in a single point and exerts a high point load on the sanitary installation
usually made of ceramics.
[0010] By using a asymmetric sealing gasket one may counteract on this imbalance by providing
a larger reaction force for the smaller lever arm and a smaller reaction force for
the longer lever arm. Generally speaking, a first part of the sealing gasket yields
to a lesser extent than a second part of the sealing gasket under the load of forces
exerted by the contact surface and the support surface on the sealing gasket.
[0011] Or otherwise stated, the first part of the sealing gasket is stiffer than the second
part.
[0012] Thereby, the sanitary fitting does not tilt during fastening and the housing base
and the contact surface are flatly pressed on the sealing gasket. This results in
a reduced point load on the sanitary installation which may prevent cracking of any
ceramic parts. Furthermore, this results in a higher resistance against twisting of
the sanitary fitting, because the sanitary fitting mainly resides on the sealing gasket
generally having a higher friction coefficient than only a small metallic backside
edge of the housing base.
[0013] Because the general shape of the sealing gasket depends on the shape of the housing
base of the sanitary fitting, the sealing gasket may have any usually used general
shape like substantially a ring shape, an elliptical shape, a rectangular shape or
the like. Even asymmetric shapes may be used, although in the context of this invention
an asymmetric sealing gasket mainly refers to the distribution of the counterforces
exerted by the sealing gasket when interposed between the contact surface and the
support surface.
[0014] The sealing gasket may or may not include further parts which are not relevant for
the distribution of the forces.
[0015] Furthermore, the first part of the sealing gasket may have a different cross section
than the second part. A different cross section provides a different stiffness even
if the same material is used for both parts of the sealing gasket.
[0016] Furthermore, the cross section of the first part may have a larger area than the
cross section of the second part. Therefore, the first part of the sealing gasket
is more massive than the second part of the sealing gasket and consequently is stiffer
if made from the same material.
[0017] Furthermore, the first part of the sealing gasket comprises a strengthening element,
in particular ribs or beadings. The stiffness of the different parts of the sealing
gasket is not only influenced by the overall area of the cross section but also by
its shape. Therefore, the first part of the sealing gasket may be stiffened by providing
strengthening elements which add additional area to the cross section area or which
are provided by a reshaped cross section having the same cross section area than the
second part.
[0018] Furthermore, the sealing gasket may have a substantially rotational symmetric geometry
but the first part is made of a material with a lower elasticity than the material
of the second part. In particular, the sealing gasket may be provided with different
shore hardness on the first and the second parts. This may be achieved for example
by a subsequent thermal hardening of the first part of an originally symmetric sealing
gasket.
[0019] The eccentric arrangement of the mounting stud bolt with respect to the contact surface
defines two lever arms having different lengths. Therefore, it is advantageous if
the stiffness of the first part and the stiffness of the second part of the sealing
gasket are chosen such that counter forces exerted by the first and the second part
compensate for the different lengths of the lever arms. This can be achieved by using
the ratio of the lever arm lengths to determine the ratio of the stiffness values
of the first and second parts.
[0020] Furthermore, the sealing gasket comprises an orientation element which allows to
properly orientate the sealing gasket with respect to the eccentric arrangement of
the mounting stud bolt. Such an orientation element may for example be a lug having
a through hole for the mounting stud bolt and protruding inwards from the sealing
gasket.
[0021] Furthermore, the first part of the sealing gasket circumferentially runs along an
angle of less than approximately 120°, in particular 90°, in particular 40°, and the
second part respectively runs along an angle of at least approximately 240°, in particular
270°, in particular 320°.
[0022] Regarding the sealing gasket the object of the invention is achieved by a sealing
gasket configured to be interposed between a contact surface of a housing base of
a sanitary fitting and a support surface around a mounting through hole of a sanitary
installation, wherein the sealing gasket is asymmetric such that a first part of the
sealing gasket yields to a lesser extent than a second part of the sealing gasket
under the load of forces exerted by the contact surface and the support surface on
the sealing gasket when a retaining element is fastened on a mounting stud bolt of
the sanitary fitting. The advantageous features mentioned above for the sanitary fitting
also apply correspondingly to the sealing gasket.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] Various features and advantages of the invention may be more readily understood with
reference to the following detailed description which refers to the following drawings
in which:
- Figure 1
- shows a side view of a sanitary fitting mounted on a sanitary installation by interposition
of a sealing gasket;
- Figure 2
- shows a side view of a sanitary fitting having a sealing gasket according to the state
of the art when a retaining element is fastened;
- Figure 3
- shows a perspective top view of a sealing gasket according to the invention;
- Figure 4
- shows a perspective bottom view of the sealing gasket according to the invention;
- Figure 5
- shows a bottom view of the sealing gasket;
- Figure 6
- shows a section along cut line A-A shown in Figure 5;
- Figure 7
- shows a perspective top view of a sealing gasket according to a second embodiment;
- Figure 8
- shows a perspective bottom view of the sealing gasket of Figure 7;
- Figure 9
- shows a bottom view of the sealing gasket of Figure 7;
- Figure 10
- shows a section along cut line A-A shown in Figure 9;
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0024] Figure 1 shows sanitary fitting 10 mounted to a mounting plate 12 of washing basin
as an exemplary sanitary installation.
[0025] For this purpose the mounting plate 12 of the washing basin comprises a mounting
through hole 14. The region adjacent to the mounting through hole 14 defines a support
surface 16, which substantially supports a housing base 18 of the sanitary fitting
10.
[0026] The housing base 18 of the sanitary fitting 10 often has a sleeve shape comprising
an inner shoulder recessing slightly in axial direction and thereby providing a contact
surface 20 which is oriented towards the mounting plate 12 and configured to receive
a sealing gasket 34. The contact surface 20 has a substantially ring shaped foot print
in accordance with the general layout of the housing base 18.
[0027] For connection of the sanitary fitting 10 to domestic plumbing lines the sanitary
fitting 10 comprises water connection lines 22 and 24 protruding from the housing
base 18.
[0028] Furthermore, the sanitary fitting 10 comprises a mounting stud bolt 26 protruding
from the housing base 18 as an integrated part of the sanitary fitting 10 or screwed
into the sanitary fitting 10. The mounting stud bolt 26 comprises a male screw thread
on which a retaining element 28 may be fastened against the mounting plate 12 using
a securing nut 30.
[0029] However, because of the space needed for the water connection lines 22, 24 the mounting
stud bolt 26 is arranged eccentrically with respect to the contact surface 20 of the
housing base 18. In particular, the mounting stud bolt 26 is radially shifted towards
the backside of the sanitary fitting 10, namely the side opposite to a protruding
water outlet 32.
[0030] In order to prevent spray water from flowing in between the housing base 18 and the
mounting plate 12, the sealing gasket 34 is interposed between the contact surface
20 of the housing base 18 and the support surface 16 around the mounting through hole
14 of the mounting plate 12.
[0031] As it can be seen from Figure 2 which shows the use of a sealing gasket 34 according
to the state of the art, the forces, which are exerted by the contact surface 20 and
the support surface 16 on the sealing gasket 34 when the retaining element 28 is fastened,
are distributed unequally because of the different lengths of the lever arms A and
B with respect to the mounting stud bolt 26.
[0032] Therefore, the sealing gasket 34 gets compressed stronger by a backside edge 36 of
the housing base 18 than by a front edge 38 of the housing base 18. Consequently,
the backside edge 36 contacts the mounting plate 12 long before the front edge 38
resulting in a tilt of the sanitary fitting 10 towards the backside edge 34 and in
a difficult fastening of the sanitary fitting 10 using a sealing gasket 34 according
to the state of the art.
[0033] Therefore, Figures 3-7 show an exemplary sealing gasket 34 according to the present
invention having a substantially round ring shape with a flat top surface 40 from
which a circumferential sleeve 42 projects axially on the outer circumference. Thereby,
a free shoulder 44 is provided pointing towards the inside, which runs along the circumference
in an angular section of approximately 320°.
[0034] Along the remaining 40° angular section of the sealing gasket 34 the sealing gasket
34 is more massive such that the space above the shoulder 44 next to the circumferential
sleeve 42 is filled. This can be best seen from Figure 6 showing a cross section of
the sealing gasket 34. The radial cross section of the sealing gasket 34 within the
40° angular section, which defines a first part 46 of the sealing gasket 34, has an
approximately rectangular, in particular quadratic, shape. In contrast, the cross
section within the other 320° angular section, which defines a second part 48 of the
sealing gasket 34, has substantially an L-shape. Therefore, the area of the cross
section of the first part 46 is larger than the cross section of the second part 48.
Consequently, the first part 46 is stiffer than the second part 48.
[0035] Furthermore, the sealing gasket 34 comprises a lug 50 which radially protrudes inwards
from the general ring shape and which provides a through hole 52 for receiving the
mounting stud bolt 26 of the sanitary fitting 10.
[0036] When mounting the sanitary fitting 10 with the sealing gasket 34 according to the
invention, the first part 46 of the sealing gasket 34 yields to a lesser extent than
a second part 48 of the sealing gasket 34 under the load of forces exerted by the
contact surface 20 and the support surface 16 when the retaining element 28 is fastened
on the mounting stud bolt 26. Accordingly, the sealing gasket 34 is more evenly compressed
even though the mounting stud bolt 26 is arranged eccentric with respect to the contact
surface 20 of the housing base 18.
[0037] Figures 7-10 show a second embodiment of the sealing gasket 34, wherein elements
having the same structural function have the same reference number.
[0038] As can be seen from Figures 7 and 10 the sealing gasket 34 according to the second
embodiment comprises a frustoconical centering shoulder 80 recessing inwards from
the flat top surface 40. Furthermore, the top surface 40 is surrounded on its circumference
by a small sealing lip 81 protruding axial upwards from the top surface 40.
[0039] Furthermore, the sealing gasket 34 comprises a centering apron 82 provided on radially
inwards and protruding downwards for centering the sealing gasket 34 inside the mounting
through hole 14.
[0040] In this embodiment of the sealing gasket 34 the first part 46 is formed by a filled
space between the centering apron 82 and the circumferential sleeve 42.
1. A sanitary fitting (10) comprising
a) a housing base (18) having a contact surface (20);
b) a mounting stud bolt (26) configured to be inserted into a mounting through hole
(14) of a sanitary installation (12), wherein the mounting stud bolt (14) is arranged
eccentrically with respect to the contact surface (20) at the housing base (18);
c) a sealing gasket (34) configured to be interposed between the contact surface (20)
of the housing base (18) and a support surface (16) around the mounting through hole
(14);
d) a retaining element (28) configured to be fastened on the mounting stud bolt (26)
on a side of mounting through hole (14) of the sanitary installation (12) opposite
to the housing base (18) in order to fasten the sanitary fitting (10) at the sanitary
installation (12);
characterized in that
e) the sealing gasket (34) is asymmetric such that a first part (46) of the sealing
gasket (34) yields to a lesser extent than a second part (48) of the sealing gasket
(34) under the load of forces exerted by the contact surface (20) and the support
surface (28) on the sealing gasket (34) when the retaining element (28) is fastened
on the mounting stud bolt (26).
2. The sanitary fitting according to claim 1, wherein the first part (46) of the sealing
gasket (34) is stiffer than the second part (48).
3. The sanitary fitting according to any of the preceding claims, wherein the first part
(46) of the sealing gasket (34) has a different cross section than the second part
(48).
4. The sanitary fitting according to claim 3, wherein the cross section of the first
part (46) has a larger area than the cross section of the second part (48).
5. The sanitary fitting according to any of the preceding claims, wherein the first part
(46) of the sealing gasket (34) comprises a strengthening element, in particular ribs
or beadings.
6. The sanitary fitting according to claim 1, wherein the sealing gasket (34) has a substantially
rotational symmetric geometry but the first part (46) is made of a material with a
lower elasticity than the material of the second part (48).
7. The sanitary fitting according to any of the preceding claims, wherein the eccentric
arrangement of the mounting stud bolt (46) with respect to the contact surface (20)
defines two lever arms (A, B) having different lengths and wherein the stiffness of
the first part (46) and the stiffness of the second part (48) of the sealing gasket
(34) are chosen such that counter forces exerted by the first part (46) and the second
part (48) compensate for the different lengths of the lever arms (A, B).
8. The sanitary fitting according to any of the preceding claims, wherein the sealing
gasket (34) comprises an orientation element (50) which allows to properly orientate
the sealing gasket (34) with respect to the eccentric arrangement of the mounting
stud bolt (26).
9. The sanitary fitting according to any of the preceding claims, wherein the first part
(46) of the sealing gasket (34) circumferentially runs along an angle of less than
approximately 120°, in particular 90°, in particular 40°, and the second part (48)
respectively runs along an angle of at least approximately 240°, in particular 270°,
in particular 320°.
10. A sealing gasket (34) for a sanitary fitting (10), wherein the sealing gasket (34)
is configured to be interposed between a contact surface (20) of a housing base (18)
of the sanitary fitting (10) and a support surface (16) around a mounting through
hole (14) of a sanitary installation (12),
characterized in that
a) the sealing gasket (34) is asymmetric such that a first part (46) of the sealing
gasket (34) yields to a lesser extent than a second part (48) of the sealing gasket
(34) under the load of forces exerted by the contact surface (20) and the support
surface (16) on the sealing gasket (34) when a retaining element (28) is fastened
on a mounting stud bolt (26) of the sanitary fitting (10).