U.S. patent application number 13/854277 was filed with the patent office on 2013-10-03 for spray arm for a dishwasher with two spray arm parts.
This patent application is currently assigned to Etimex Technical Components GmbH. The applicant listed for this patent is ETIMEX TECHNICAL COMPONENTS GMBH. Invention is credited to Heinz Hermann, Marc Vogt.
Application Number | 20130255734 13/854277 |
Document ID | / |
Family ID | 47832835 |
Filed Date | 2013-10-03 |
United States Patent
Application |
20130255734 |
Kind Code |
A1 |
Hermann; Heinz ; et
al. |
October 3, 2013 |
SPRAY ARM FOR A DISHWASHER WITH TWO SPRAY ARM PARTS
Abstract
In a spray arm for a dishwasher, comprising a first spray arm
part and a second spray arm part, of which the first spray arm part
comprises a groove which extends substantially along the
circumference of the first spray arm part, said groove being formed
by a first, inner groove wall and a second, outer groove wall, and
of which the second spray arm part comprises a web wall which
extends substantially along the circumference of the second spray
arm part and engages with the groove, the web wall comprises a
first latching element which, in order to establish a latching
connection between the first and the second spray arm part, is
designed to interact with a second latching element which is
located on one of the groove walls.
Inventors: |
Hermann; Heinz;
(Biberach/Rib, DE) ; Vogt; Marc; (Opfingen,
DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
ETIMEX TECHNICAL COMPONENTS GMBH |
Rottenacker |
|
DE |
|
|
Assignee: |
Etimex Technical Components
GmbH
Rottenacker
DE
|
Family ID: |
47832835 |
Appl. No.: |
13/854277 |
Filed: |
April 1, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61739306 |
Dec 19, 2012 |
|
|
|
Current U.S.
Class: |
134/198 |
Current CPC
Class: |
A47L 15/4278 20130101;
A47L 15/23 20130101 |
Class at
Publication: |
134/198 |
International
Class: |
A47L 15/42 20060101
A47L015/42 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 30, 2012 |
DE |
10 2012 006 379.2 |
Claims
1. Spray arm (10) for a dishwasher, comprising a first spray arm
part (20) and a second spray arm part (24), of which the first
spray arm part (20) comprises a groove (28) which extends
substantially along the circumference of the first spray arm part
(20), said groove being formed by a first, inner groove wall (30)
and a second, outer groove wall (32), and of which the second spray
arm part (24) comprises a web wall (34) which extends substantially
along the circumference of the second spray arm part (24) and
engages with the groove (28), the web wall (34) comprising a first
latching element (41) which, in order to establish a latching
connection (40) between the first and the second spray arm part
(20; 24), is designed to interact with a second latching element
(42) which is located on one of the groove walls (30; 32).
2. Spray arm of claim 1, wherein the first latching element (41) is
embodied on the outside of the web wall (34) and the second
latching element (42) is embodied on the second, outer groove wall
(32).
3. Spray arm of claim 2, wherein the second, outer groove wall (32)
is designed to be higher than the first, inner groove wall
(30).
4. Spray arm of claim 3, wherein the first, inner groove wall (30)
is designed with an insertion chamfer (46) on its rim facing the
web wall (34) for insertion of the web wall (34) into the groove
(28).
5. Spray arm of claim 4, wherein the second, outer groove wall (32)
is designed with an insertion chamfer (48) on its rim facing the
web wall (34) for insertion of the web wall (34) into the groove
(28).
6. Spray arm of claim 5, wherein the web wall (34) is designed with
an insertion chamfer (50, 52) on at least one of its rims facing
the groove walls (30; 32) for insertion of the web wall (34) into
the groove (28).
7. Spray arm of claim 6, wherein the first latching element (41) is
designed as a detent lug and the second latching element (42) as a
detent recess.
8. Spray arm of claim 7, wherein the first latching element (41)
and the second latching element (42) are designed to extend
substantially along the entire circumference of the first and the
second spray arm part (20; 24).
9. Spray arm of claim 8, wherein the first latching element (41)
and the second latching element (42) are designed with an
interruption by a short gap (44) at predetermined spacings along
the circumference of the first and the second spray arm part (20:
24).
10. Spray arm according of claim 9, wherein at least one channel
(54) leads from the outside into the groove (28) for accommodating
a mass connecting the first spray arm part (20) with the second
spray arm part (24).
11. Spray arm of claim 1, wherein the second, outer groove wall
(32) is designed to be higher than the first, inner groove wall
(30).
12. Spray arm of claim 1, wherein the first, inner groove wall (30)
is designed with an insertion chamfer (46) on its rim facing the
web wall (34) for insertion of the web wall (34) into the groove
(28).
13. Spray arm of claim 1, wherein the second, outer groove wall
(32) is designed with an insertion chamfer (48) on its rim facing
the web wall (34) for insertion of the web wall (34) into the
groove (28).
14. Spray arm of claim 1, wherein the web wall (34) is designed
with an insertion chamfer (50, 52) on at least one of its rims
facing the groove walls (30; 32) for insertion of the web wall (34)
into the groove (28).
15. Spray arm of claim 1, wherein the first latching element (41)
is designed as a detent lug and the second latching element (42) as
a detent recess.
16. Spray arm of claim 1, wherein the first latching element (41)
and the second latching element (42) are designed to extend
substantially along the entire circumference of the first and the
second spray arm part (20; 24).
17. Spray arm of claim 16, wherein the first latching element (41)
and the second latching element (42) are designed with an
interruption by a short gap (44) at predetermined spacings along
the circumference of the first and the second spray arm part (20:
24).
18. Spray arm according of claim 1, wherein at least one channel
(54) leads from the outside into the groove (28) for accommodating
a mass connecting the first spray arm part (20) with the second
spray arm part (24).
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority on U.S. Provisional Patent
Appl. No. 61/739,306 filed on Dec. 19, 2012, the entire disclosure
of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The invention relates to a spray arm for a dishwasher,
comprising a first spray arm part and a second spray arm part, of
which the first spray arm part comprises a groove which extends
substantially along the circumference of the first spray arm
part.
[0004] 2. Description of the Related Art
[0005] In dishwashers, in particular in those used as domestic
appliances, rotating spray arms are provided for supplying and
distributing washing water in an associated washing compartment.
The spray arms are usually assembled using two spray arm parts
which enclose a cavity. The washing water is introduced into the
cavity and is thereafter sprayed into the washing compartment of
the dishwasher by means of nozzles, the nozzles being located on at
least one of the spray arm parts.
[0006] In order to ensure proper functioning of such a spray arm,
its cavity has to be enclosed tightly sealed by the two spray arm
parts. Furthermore, the manufacture and the assembly of the spray
arm parts must be cost-effective, as the cost pressure in the
manufacturing and the assembly of such dishwashers is very high,
particularly in the field of domestic appliances but also in the
field of industrial appliances.
[0007] The object underlying the invention is to provide a
dishwasher with a spray arm, of which the spray arm parts may be
manufactured and assembled in a particularly cost-effective way,
but at the same time meet the requirements in respect of
leaktightness over the service life.
SUMMARY OF THE INVENTION
[0008] The object is achieved according to the invention with a
spray arm for a dishwasher, comprising a first spray arm part and a
second spray arm part, of which the first spray arm part comprises
a groove which extends substantially along the circumference of the
first spray arm part, said groove being formed by a first, inner
groove wall and a second, outer groove wall, and of which the
second spray arm part comprises a web wall which extends
substantially along the circumference of the second spray arm part
and engages with the groove, the web wall comprising a first
latching element which, in order to establish a latching connection
between the first and the second spray arm part, is designed to
interact with a second latching element which is located on one of
the groove walls.
[0009] The solution according to the invention provides a cavity
which can be manufactured cost-effectively and is sealed toward the
outside and conducts fluid. The cavity herein is already sealed
without any additional measures upon connection of the two spray
arm parts to one another. No separate production step is required
in order to seal the components joined with one another. The
sealing is ensured only by the groove and the web wall inserted
into it, with the components at the same time being permanently
coupled to one another by means of the latching connection
provided. The inner groove wall serves as an additional support for
the web wall and in this way increases the strength of the
connection. The structure of the groove provided by the invention
creates double side walls in the spray device. This is advantageous
with a view to torsional stiffness and the stability of the
assembled spray arm. The double design of the wall is implemented
at the points exhibiting the greatest stress, shearing forces and
pressure impulses and at the same time the lowest bending
strength.
[0010] In particular, the solution according to the invention does
not necessitate any separate process steps for sealing or joining,
as in, for instance, paddle welding, vibration welding or
overmolding of conventional spray arm parts. Additionally, the risk
of leaks or distortion as indeed occurs in conventional
manufacturing methods for spray arms is avoided. As a result,
according to the invention, the requirements in terms of technical
equipment for the manufacture and assembly, and the associated
investment costs, are reduced. Moreover, the solution according to
the invention can be very well integrated into any automated
manufacturing process with short cycle times, in particular with a
view to a short-cycle injection molding process for the manufacture
of the respective spray arm parts.
[0011] Based on the solution according to the invention, a spray
arm may be manufactured which also satisfies high esthetic
requirements, as exist today for a spray arm, this being a visible
part of a dishwasher.
[0012] To this end, in particular the first latching element is
embodied on the outside of the web wall and the second latching
element is embodied on the second, outer groove wall. The latching
connection of this kind is located, hidden from the viewer from the
outside, between the outer groove wall and the web wall. Indeed, in
this solution no latch cams, as may be conventionally known from
other applications, are identifiable. Because such latch cams
should not be visible, such latch cams have hitherto been used only
on, for instance, spray arms of the so-called third spray level,
where the spray arm is located very close to the ceiling of the
washing compartment. There, not only is the visibility of the spray
arm is limited, but there is also no requirement for a high level
of leaktightness.
[0013] In the solution according to the invention, it is
particularly preferable that the second, outer groove wall is
designed to be higher than the first, inner groove wall. In this
instance, the outer groove wall extends particularly far beyond the
web wall, with sufficient space for the location of a latching
connection thus being available below. At the same time, the groove
walls of different height permit the web wall to be inserted into
the groove in a stepped manner, said web wall being first aligned
along the outer groove wall and only then being inserted into the
rear or deeper section of the groove for the purpose of sealing by
means of the inner groove wall. This stepped insertion into the
groove is particularly advantageous with a view to an automated
assembly and the leaktightness of the functional group thus
achievable.
[0014] In order to further facilitate the assembly of the
functional group according to the invention, the first, inner
groove wall is preferably also designed with an insertion chamfer
on its rim facing the web wall for insertion of the web wall into
the groove, the second, outer groove wall is preferably also
designed with an insertion chamfer on its rim facing the web wall
for insertion of the web wall into the groove, and/or the web wall
is preferably also designed with an insertion chamfer on at least
one of its rims facing the groove walls for insertion of the web
wall into the groove.
[0015] For the latching connection according to the invention, the
first latching element is preferably designed as a detent lug and
the second latching element as a detent recess. With a latching
geometry of this kind, a high strength of the latching connection
may be achieved with a comparatively narrow latching width.
[0016] The first latching element and the second latching element
are furthermore preferably designed to extend substantially along
the entire circumference of the first and the second spray arm
part. By means of the thus substantially completely surrounding
latching connection, the two spray arm parts are coupled together
in a uniformly tight manner along their entire circumference. The
risk of any local detachment, loosening or bursting open of the
connection is thus minimized, given at the same time a
comparatively low locking force. The surrounding latching may
herein be advantageously combined on at least one of the spray arm
parts with a surrounding sealing lip, which in the latching process
with its counterpart is compressed and deformed along the entire
circumference. Such a sealing lip is, however, not mandatory.
Rather, the surrounding latching according to the invention
especially additionally forms a labyrinth which significantly
contributes to the mutual sealing of the two spray arm parts. The
solution according to the invention thus achieves an optimum
balance between joining force and deformation and leaktightness.
The particular embodiment of the latching geometry according to the
invention additionally contributes toward leaktightness being
ensured along the entire circumference of the two spray arm
parts.
[0017] Moreover, it is advantageous that the first latching element
and the second latching element are designed with an interruption
by a short gap at predetermined spacings along the circumference of
the first and the second spray arm part. Such interruptions of the
latching elements advantageously extend over a gap of 0.5 cm to 1.5
cm, particularly preferably approx. 1.0 cm, and are of advantage in
particular with a view to the shaping of the injection molds used
for the spray arm parts.
[0018] Finally, the solution according to the invention is also
outstandingly suited to providing at least one channel leading from
the outside into the groove for accommodating a mass connecting the
first spray arm part with the second spray arm part. The mass
introduced into the channel may ensure an additional means of
sealing and a cohesive connection of the two spray arm parts, if so
desired.
[0019] In the following, exemplary embodiments of the solution
according to the invention are explained in more detail with
reference to the attached schematic drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] FIG. 1 shows a first perspective view of a first spray arm
according to the invention with its two spray arm parts prior to
assembly.
[0021] FIG. 2 shows a second perspective view of the spray arm
parts shown in FIG. 1.
[0022] FIG. 3 shows a perspective view of the spray arm parts shown
in FIG. 1 after assembly to form the complete spray arm.
[0023] FIG. 4 shows the cross section IV-IV in FIG. 1.
[0024] FIG. 5 shows the cross section V-V in FIG. 3.
[0025] FIG. 6 shows the detail VI in FIG. 5.
[0026] FIG. 7 shows the view shown in FIG. 5 for a variant of a
spray arm according to the invention.
[0027] FIG. 8 shows a perspective view of a second spray arm
according to the invention with its two spray arm parts prior to
assembly.
[0028] FIG. 9 shows a perspective view of the spray arm parts shown
in FIG. 8 after assembly to form the complete spray arm.
[0029] FIG. 10 shows a perspective view of a third spray arm
according to the invention with its two spray arms prior to
assembly.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0030] The figures show a spray arm 10 of a domestic dishwasher
which is not illustrated, comprising a vertical hollow-cylindrical
hub section 12, with two arm sections 14 and 16 extending
horizontally therefrom in opposite directions. When fitted to the
dishwasher, the spray arm 10 is supplied through the hub section 12
with water under pressure, which water then sprays out through the
nozzles 18 which are arranged distributed on the spray arm 10.
[0031] The nozzles 18 are distributed on the upper side 19 of an
upper, shell-shaped spray arm part 20 and, if appropriate, also on
the lower side 22 of a lower, also shell-shaped spray arm part 24.
The spray arm parts 20 and 24 herein are made of plastic by means
of injection molding or alternatively of metal, in particular of
stainless steel, by means of deep-drawing, and are each placed
against one another by way of their shell shape such that a cavity
26 is created.
[0032] The region of the joint or connection between the two shells
placed against one another in such a way is sealed and coupled in a
form-fitting manner. To this end, a groove 28 which extends
substantially along its circumference is embodied on the upper
spray arm part 20, said groove being formed by a first, inner
groove wall 30 and a second, outer groove wall 32. Furthermore, a
web wall 34 which also extends substantially along its entire
circumference and engages with the groove 28 is embodied on the
lower spray arm part 24.
[0033] The web wall 34 is, at its top, designed to be so high that
it is sealed against the upper spray arm part 20 right up to the
base of the groove 28 and there in a first, upper seal region 36
(refer to FIG. 6) by pressing in a force-fitting manner.
Furthermore, the groove 28 is designed to be so narrow that the web
wall 34, when inserted into the groove 28, is laterally forced
against the inner groove wall 30, where it is also sealed in a
second lateral seal region 38 (refer again to FIG. 6) against the
upper spray arm part 20. Alternatively, the web wall 34 is designed
to be so high and/or wide that it lies against the walls of the
groove 28 without any major contact pressure. In this instance,
sealing between the upper spray arm part 20 and the lower spray arm
part 24 is essentially achieved solely as a result of the
labyrinth-type geometry of groove 28 and web wall 34.
[0034] A latching connection 40 is further achieved between the
upper spray arm part 20 and the lower spray arm part 24, by means
of which connection the two parts are coupled to one another in a
form-fitting manner. The form-fitting coupling is made without a
separate production step when joining the spray arm part 20 and the
spray arm part 24 during assembly of the spray arm 10. For this
purpose, the web wall 34 on the lower spray arm part 24 comprises a
first latching element 41 on its outside which interacts with a
second latching element on the inside of the outer groove wall 32.
The latching connection 40 of this kind is not visible to anyone
viewing the spray arm 10 from the outside.
[0035] The first latching element 41 is designed as a detent lug
and the second latching element 42 as a detent recess, both
extending substantially along the entire circumference of the first
and the second spray arm part 20 or 24, respectively, and only
being interrupted by a short gap 44 at predetermined spacings along
the circumference.
[0036] The second, outer groove wall 32 is designed to be higher
than the first, inner groove wall 30 and extends far beyond the web
wall 34 when the lower spray arm part 24 is brought together with
the upper spray arm part 20. Moreover, the first, inner groove wall
30 is designed with an insertion chamfer 46 on its rim facing the
web wall 34 for insertion of the web wall 34 into the groove 28,
the second, outer groove wall 32 is designed with an insertion
chamfer 48 on its rim facing the web wall 34 also for insertion of
the web wall 34 into the groove 28, and the web wall 34 itself is
designed with an insertion chamfer 50 and 52 on each of its two
rims facing the groove walls 30 and 32. By means of these insertion
chamfers 46, 48, 50 and 52, the insertion of the web wall 34 into
the groove 28 overall is also possible in the event of relatively
large dimensional differences between spray arm part 20 and spray
arm part 24.
[0037] FIG. 7, finally, shows a variant of a spray arm 10 in which
a plurality of channels 54 for accommodating a mass connecting the
first spray arm part 20 with the second spray arm part 24 are
distributed along the circumference on the upper rim region of the
upper spray arm part 20. The mass may be introduced into the
channels 54 during the assembly process, in particular in order to
be distributed within the groove 28 above the web wall 34, for
additional sealing and for cohesive connection of the two spray arm
parts 20 and 24.
[0038] FIGS. 8 and 9 show a spray arm 10, of which the spray arm
part 20 is also designed with a groove 28, an inner groove wall 30
and an outer groove wall 32. A substantially vertical slot 56 is
formed in the outer groove wall 32 approximately in the center of
each arm section 14 and 16. The slot 56 extends substantially along
the entire height of the groove wall 32 and is open toward the
outside and/or accessible from outside. A fin 58 is inserted in the
slot 56 of this kind in a form-fitting manner when the two spray
arm parts 20 and 24 are joined, said fin 58 being embodied at a
corresponding position on the exterior of the web wall 34 of the
lower spray arm part 24. The fins 58 of this kind, of which a total
of four are located on the circumference of the spray arm part 24,
in interaction with the four associated slots 56 on the upper spray
arm part 20, serve as stiffening elements and in particular prevent
any distortion of the spray arm 10 when water passes through it in
the operational state and thus sets it in rotational motion.
[0039] FIG. 10 shows a spray arm 10 in which, in a functionally
similar manner, vertical slots 56 are embodied on the inner groove
wall 30 and fins 58 are embodied on the inner side of the web wall
34. This arrangement of the slots 56 and the form-fitting ribs 58
results in a stiffening effect which is not visible from
outside.
[0040] In concluding, it should be observed that all features
mentioned in the application documents and, in particular, in the
dependent claims are to be protected in their own right
individually or in any combination with one another,
notwithstanding the formal references made to one or more specific
claims.
* * * * *