U.S. patent application number 17/306599 was filed with the patent office on 2021-08-19 for sealing element and method for producing a sealing element.
The applicant listed for this patent is ElringKlinger AG. Invention is credited to Klaus Hocker, Walter Schuhmacher.
Application Number | 20210254720 17/306599 |
Document ID | / |
Family ID | 1000005555364 |
Filed Date | 2021-08-19 |
United States Patent
Application |
20210254720 |
Kind Code |
A1 |
Hocker; Klaus ; et
al. |
August 19, 2021 |
SEALING ELEMENT AND METHOD FOR PRODUCING A SEALING ELEMENT
Abstract
In order to provide a sealing element, in particular for use as
a rod seal, piston seal and/or shaft seal, which ensures a reliable
seal and which can be produced easily and economically, it is
proposed that the sealing element includes a main body formed from
a thermoplastic material, wherein the main body has obtained at
least part of its final outer shape in a high-pressure process
and/or in a high-temperature process.
Inventors: |
Hocker; Klaus; (Ingersheim,
DE) ; Schuhmacher; Walter; (Bietigheim-Bissingen,
DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
ElringKlinger AG |
Dettinggen |
|
DE |
|
|
Family ID: |
1000005555364 |
Appl. No.: |
17/306599 |
Filed: |
May 3, 2021 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
15606238 |
May 26, 2017 |
|
|
|
17306599 |
|
|
|
|
PCT/EP2015/077942 |
Nov 27, 2015 |
|
|
|
15606238 |
|
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F16J 15/3284 20130101;
F16J 15/328 20130101; F16J 15/3208 20130101; B29C 45/0001 20130101;
F16J 15/3236 20130101; B29C 45/37 20130101; B29C 45/0055
20130101 |
International
Class: |
F16J 15/3284 20060101
F16J015/3284; B29C 45/00 20060101 B29C045/00; F16J 15/3236 20060101
F16J015/3236; F16J 15/328 20060101 F16J015/328; F16J 15/3208
20060101 F16J015/3208; B29C 45/37 20060101 B29C045/37 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 28, 2014 |
DE |
10 2014 224 378.5 |
Claims
1. A sealing element, comprising a main body formed from a
thermoplastic material which has obtained only part of its final
outer shape in a high-pressure process or in a high-temperature
process, which is an injection molding process, wherein the main
body consists of a fluoro-thermoplastic material, wherein the main
body is annular and comprises two radially inner dynamic sealing
portions for dynamically sealing between the sealing element and a
movable component, wherein the main body further comprises one or
more radially outer sealing portions,0 wherein each dynamic sealing
portion comprises one, two or more than two sealing lips, wherein
the dynamic sealing portions have obtained their respective final
outer shape by machining, wherein the one or more radially outer
sealing portions have obtained their final outer shape in the
high-pressure process or in the high-temperature process, wherein
the main body is an injection-molded component.
2. The sealing element according to claim 1, wherein the main body
only in part has a surface finish which comprises a body formed or
completed in a high-pressure process or in a high-temperature
process.
3. The sealing element according to claim 1, wherein the main body
only in part has a surface finish which comprises a body formed or
completed in an injection molding process.
4. The sealing element according to claim 1, wherein the sealing
element is configured for use as a rod seal, piston seal or shaft
seal, in particular in a fuel pump or a piston pump.
5. The sealing element according to claim 1, wherein the sealing
element is a spring assisted grooved ring.
6. The sealing element according to claim 1, wherein the
flouro-thermoplastic material of the main body is
melt-processable.
7. A method for producing a sealing element, comprising: producing
a main body of the sealing element from a thermoplastic material,
wherein the main body obtains only part of its final outer shape in
a high-pressure process or in a high-temperature process, wherein
the main body consists of a fluoro-thermoplastic material, wherein
the main body is annular and comprises two radially inner dynamic
sealing portions for dynamically sealing between the sealing
element and a movable component, wherein the main body further
comprises one or more radially outer sealing portions, wherein each
dynamic sealing portion comprises one, two or more than two sealing
lips, wherein the dynamic sealing portions obtain their respective
final outer shape by machining, wherein the one or more radially
outer sealing portions obtain their final outer shape in the
high-pressure process or in the high-temperature process, wherein
the high-pressure process or the high-temperature process is an
injection molded process.
8. The method according to claim 7, wherein the main body of the
sealing element is subjected to a finishing operation only in part
after the high-pressure process or the high-temperature process has
been performed.
9. The method according to claim 8, wherein the main body is
coated.
10. The method according to claim 7, wherein the main body is
produced from partially fluorinated or fully fluorinated
thermoplastic material which in particular is
injection-moldable.
11. The sealing element according to claim 1, wherein each of the
one, two or more than two sealing lips are substantially
annular.
12. The sealing element according to claim 1, wherein an axis of
symmetry is defined parallel to a longitudinal axis of the movable
component and the sealing element, and wherein each of the one, two
or more than two sealing lips are substantially rotationally
symmetrical about the axis of symmetry.
13. The sealing element according to claim 1, wherein each of the
two radially inner dynamic sealing portions are configured to be
pressed against the movable component by means of one or more
spring elements.
14. The sealing element according to claim 13, wherein the main
body further comprises one or more spring element receptacles
configured to receive the one or more spring elements.
15. The sealing element according to claim 1, wherein the one, two
or more than two sealing lips are arranged at different spacings
from a transverse central plane of the sealing element which runs
at a right angle to a longitudinal axis of the sealing element.
Description
RELATED APPLICATION
[0001] This application is a continuation of U.S. application Ser.
No. 15/606,238 filed on May 26, 2017, which is a continuation of
international application No. PCT/EP2015/077942 filed on Nov. 27,
2015, and claims the benefit of German application No. 10 2014 224
378.5 filed on Nov. 28, 2014 which are incorporated herein by
reference in their entirety and for all purposes.
FIELD OF DISCLOSURE
[0002] The present invention relates to a sealing element, in
particular for use as a rod seal, piston seal and/or shaft
seal.
[0003] Such a sealing element is known by way of example from DE 10
2012 112 594 A1.
SUMMARY OF THE INVENTION
[0004] The object of the present invention is to provide a sealing
element which ensures a reliable seal and which can be produced
easily and economically.
[0005] This object is achieved in accordance with the invention by
a sealing element which comprises a main body made of a
thermoplastic material, wherein the main body has obtained at least
part of its final outer shape in a high-pressure process and/or in
a high-temperature process.
[0006] Alternatively, it can be provided that the sealing element
comprises a main body made of a thermoplastic material, wherein the
main body has obtained only part of its final outer shape in a
high-pressure process and/or in a high-temperature process.
[0007] The sealing element, in particular the main body of the
sealing element, is preferably produced with near net shape.
[0008] A final outer shape is in particular the shape that the main
body has in the state of use of the sealing element or in the state
ready for use.
[0009] A final outer shape is also in particular a shape in which
there is no further processing, for example no re-shaping of the
surface, before the main body is used as intended as part of the
sealing element.
[0010] It can be advantageous if the main body, at least in part or
only in part, has a surface finish which comprises a body shaped
and/or completed in a high-pressure process and/or in a
high-temperature process.
[0011] It can be advantageous if the main body, at least in part or
only in part, has a surface finish which comprises a body shaped
and/or completed in an injection molding process.
[0012] In one embodiment of the invention it can be provided that
the main body is substantially ring-shaped.
[0013] The main body preferably comprises one or more radially
inner sealing portions and also one or more radially outer sealing
portions with respect to the ring shape.
[0014] For simplification, the sealing portions will be discussed
hereinafter in the singular. However, a plurality of sealing
portions having one or more of the mentioned features can of course
also be provided at all times.
[0015] The main body can be circular ring-shaped by way of
example.
[0016] A radially inner sealing portion serves preferably to
provide a dynamic seal on a movable element, in particular a
piston, a rod, or a shaft.
[0017] A radially outer sealing portion serves preferably to
provide a static seal on a housing of a sealing device.
[0018] It can be favorable if the radially inner sealing portion
and/or the radially outer sealing portion have/has obtained
their/its final outer shape in the high-pressure process and/or in
the high-temperature process.
[0019] It can be provided here that only the radially inner sealing
portion or only the radially outer sealing portion or both the
radially inner sealing portion and the radially outer sealing
portion has/have obtained its/their final outer shape in the
high-pressure process and/or in the high-temperature process.
[0020] Alternatively or additionally, it can be provided that a
radially inner sealing portion and/or a radially outer sealing
portion have/has obtained the corresponding final outer shape by
means of a finishing operation, for example a machining
operation.
[0021] In a further development of the invention it can be provided
that the main body comprises two ends which are opposite one
another with respect to an axial direction and which in particular
in the state of use of the sealing element come into contact with
fluids to be separated from one another.
[0022] Only one of the ends or both ends has/have obtained the
final outer shape preferably in the high-pressure process and/or in
the high-temperature process.
[0023] Alternatively or additionally, it can be provided that only
one of the ends or both ends has/have obtained the final outer
shape by means of a finishing operation, for example a machining
operation.
[0024] One end or both ends is/are preferably provided with one or
more spring element receptacles for receiving one or more spring
elements.
[0025] It can be favorable if the main body comprises a
thermoplastic material which in particular is injection-moldable,
or is formed from a thermoplastic material which in particular is
injection-moldable.
[0026] The thermoplastic material can be in particular a
fluoro-thermoplastic material, for example a fully fluorinated
thermoplastic material.
[0027] The main body is preferably an injection-molded component,
in particular a plastics injection-molded component.
[0028] The sealing element can be a spring-assisted grooved ring,
for example.
[0029] The sealing element then preferably comprises one or more
spring elements, which for example are formed from a spring steel
and have a ring shape at least roughly.
[0030] Here, one or more spring elements by way of example can have
a U-shaped, V-shaped or L-shaped cross-section as considered at
right angles to a circumferential direction.
[0031] The present invention also relates to the use of a sealing
element, in particular a sealing element according to the
invention, as a rod seal, piston seal and/or shaft seal.
[0032] Here, the sealing element is preferably used in a fuel pump
and/or a piston pump for sealing two media spaces.
[0033] The use according to the invention preferably has one or
more of the features and/or advantages described in conjunction
with the sealing element according to the invention.
[0034] The present invention also relates to a method for producing
a sealing element.
[0035] In this regard, the object of the invention is to provide a
method by means of which a sealing element that provides a reliable
seal can be produced easily and economically.
[0036] This object is achieved in accordance with the invention by
a method for producing a sealing element, wherein the method
comprises the following: producing a main body of the sealing
element from a thermoplastic material, wherein the main body
obtains at least part of its final outer shape or only part of its
final outer shape in a high-pressure process and/or in a
high-temperature process.
[0037] The method according to the invention preferably has one or
more of the features and/or advantages described in conjunction
with the sealing element according to the invention and/or the use
according to the invention.
[0038] It can be favorable if the high-pressure process comprises
an embossing process, a press molding process, an injection molding
process and/or a pressure diecasting process.
[0039] The main body thus obtains at least part of its final outer
shape or only part of its final outer shape preferably in an
embossing process, a press molding process, an injection molding
process and/or a pressure diecasting process.
[0040] Alternatively or additionally, it can be provided that the
high-temperature process comprises a hot embossing process, a hot
press molding process, an injection molding process, a casting
process, a sintering process and/or a thermoforming process.
[0041] The main body thus obtains at least part of its final outer
shape or only part of its final outer shape preferably in a hot
embossing process, a hot press molding process, an injection
molding process, a casting process, a sintering process and/or a
thermoforming process.
[0042] It can be favorable if the main body of the sealing element
is subjected to a finishing operation only in part after the
high-pressure process and/or the high-temperature process have/has
been performed.
[0043] By way of example, a partial finishing only on one side can
be provided, in particular a one-sided finishing axially and/or
radially.
[0044] However, it can also be provided that the main body is
subjected to a finishing operation on both sides in the axial
direction and/or on both sides in the radial direction.
[0045] The main body is preferably machined.
[0046] Alternatively or additionally, it can be provided that the
main body is coated for the finishing or as the finishing.
[0047] One or more sealing portions of the sealing element is/are
preferably produced by a processing of the main body.
[0048] By way of example, it can be provided that one or more
dynamic sealing portions of the sealing element and/or one or more
static sealing portions of the sealing element have/has been
produced by a processing, in particular a machining, of the main
body.
[0049] One or more spring element receptacles for receiving one or
more spring elements is/are preferably not subjected to a finishing
operation, but instead obtains/obtain its/their final outer shape
preferably in the high-pressure process and/or in the
high-temperature process.
[0050] It can be particularly advantageous if the main body is
produced from partially fluorinated or fully fluorinated
thermoplastic material which preferably is injection-moldable.
[0051] It can be provided that the main body is formed from pure
PTFE material.
[0052] The thermoplastic material (plastics material) is preferably
melt-processable.
[0053] The plastics material used is preferably a TFE copolymer
with a comonomer content of more than 0.5 wt. %. By means of a
comonomer content of this order, the molecular weight of the
polymer chains can be reduced without detriment to the mechanical
strength of the material, and therefore the melt viscosity is
reduced and processing by means of injection molding is made
possible.
[0054] The comonomer is preferably selected from a perfluoroalkyl
vinyl ether, in particular perfluoromethyl vinyl ether,
hexafluoropropylene and perfluoro-(2,2-dimethyl-1,3-dioxole).
Depending on the comonomer content, the fully fluorinated
thermoplastic is then what is known as a melt-processable PTFE
(comonomer content up to approximately 3 wt. %), a PFA (more than
approximately 3 wt. % perfluoroalkyl vinyl ether as comonomer), an
MFA (more than approximately 3 wt. % perfluoromethyl vinyl ether as
comonomer), or an FEP (more than approximately 3 wt. %
hexafluoropropylene as comonomer).
[0055] The TFE copolymer can also comprise different comonomers. It
is also possible that the fully fluorinated thermoplastic comprises
a mixture of different TFE copolymers.
[0056] The material of the main body can be formed in part or
substantially completely from the fully fluorinated thermoplastic.
Alternatively or additionally, the material can comprise one or
more fillers, in particular pigments, friction-reducing additives
and/or additives increasing the thermal resistance, in order to
further optimize the properties of the sealing element and to adapt
these to the relevant requirements.
[0057] The sealing element is suitable in particular for sealing
pistons in high-pressure fuel pumps or piston pumps for brake
systems (ABS, ESP, etc.).
[0058] In particular, a thermoplastic material that is resistant to
high temperature and/or chemicals, in particular PEEK, PEAK, PEI,
etc., and/or a compound material comprising one or more of the
above-mentioned materials can also be used as thermoplastic
material.
[0059] A high dimensional stability of the thermoplastic material
can be attained in particular by production of the main body of the
sealing element in an injection molding process so as to ultimately
seal off higher pressures in particular.
[0060] The high-pressure process is in particular a high-pressure
forming process.
[0061] The high-temperature process is preferably a
high-temperature forming process and/or a high-temperature
conversion process.
[0062] It can be provided that the high-pressure process and/or the
high-temperature process are/is the only process steps or step for
producing the main body.
[0063] Alternatively, further process steps can be carried out in
order to produce the main body.
[0064] By way of example, in order to produce a main body of a
sealing element, it can be provided that the thermoplastic material
is pre-fabricated in an extrusion process, in particular a ram
extrusion process, and is then brought into the final outer shape
by grinding and milling, turning, or other machining operation.
[0065] It can also be provided that a main body of a sealing
element is produced by carrying out the following method steps:
extruding the thermoplastic material, in particular ram-extruding
the thermoplastic material; grinding; machining in a turning
machine; hot embossing; CNC finishing, in particular in order to
produce an inner contour, for example one or more radially inner
sealing portions.
[0066] In a further embodiment it can be provided that a main body
of the sealing element is produced by carrying out the following
method steps: pressing a blank; carrying out a sintering process;
hot embossing; CNC processing, in particular in order to produce an
inner contour, for example one or more radially inner sealing
portions.
[0067] A main body of a sealing element can also be produced for
example by carrying out the following method steps: pressing a
blank; carrying out a sintering process; CNC processing of the main
body, in particular in order to produce an outer contour and/or an
inner contour, for example in order to produce one or more radially
inner sealing portions and/or one or more radially outer sealing
portions.
[0068] A main body of a sealing element can also be produced by
carrying out the following method steps: granulating a starting
material; using this starting material in an injection molding
process in order to produce the main body; subjecting the main body
to a finishing operation as appropriate, in particular CNC
processing in order to produce an inner contour, for example one or
more radially inner sealing portions.
[0069] A completed main body can be connected as appropriate to
further components of the sealing element, or can be assembled
thereon, and finally packaged.
[0070] Further preferred features and/or advantages of the
invention are the subject of the following description and the
representation in the drawings of exemplary embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0071] FIG. 1 shows a schematic longitudinal section through a main
body of a sealing element, wherein the main body has its final
outer shape only in part;
[0072] FIG. 2 shows a schematic illustration, corresponding to FIG.
1, of the main body, wherein the main body has been processed to
complete an outer contour; and
[0073] FIG. 3 shows a schematic illustration, corresponding to FIG.
1, of a sealing element which comprises the completed main body and
two spring elements.
[0074] In all figures, like or functionally equivalent elements are
provided with the same reference signs.
DETAILED DESCRIPTION OF THE DRAWINGS
[0075] An embodiment illustrated in FIGS. 1 to 3 of a sealing
element denoted as a whole by 100 is, for example, part of a
high-pressure pump 102 and serves to provide a seal between two
media spaces 104 in the region of a movable component 106.
[0076] The movable component 106 can be a piston of the
high-pressure pump 102, for example.
[0077] The movable component 106 is in particular guided through
the sealing element 100.
[0078] Here, both the movable component 106 and the sealing element
100 are preferably rotationally symmetrical about an axis of
symmetry 108.
[0079] The axis of symmetry 108 is in particular oriented parallel
to a longitudinal axis 110 of the movable component 106 and of the
sealing element 100.
[0080] The sealing element 100 and the movable component 106 have a
common axis of symmetry 108 in the assembled state.
[0081] The longitudinal axis 110 preferably defines an axial
direction 112.
[0082] A direction oriented at right angles to the axial direction
112 is a radial direction 114.
[0083] The media spaces 104 are preferably separated from one
another in the axial direction 112 by means of the sealing element
100.
[0084] The sealing element 100 here borders the movable component
106 in the radial direction 114 in an inwardly directed manner by
means of two dynamic sealing portions 116.
[0085] The sealing element 100 borders a housing 118 of the
high-pressure pump 102 in an outwardly directed manner in the
radial direction 114.
[0086] The sealing element 100, in the assembled state, is fixed
relative to the housing 118.
[0087] Two sealing regions 120 of the sealing element 100
associated with the two media spaces 104 thus comprise, in addition
to the dynamic sealing portions 116, also two static sealing
portions 122 bearing against the housing 118.
[0088] The dynamic sealing portions 116 serve to provide the
dynamic seal between the sealing element 100 and the component 106
moving relative to the sealing element 100, in particular
displaceable along the axial direction 112.
[0089] In order to attain an increased sealing effect, one or more
spring elements 124 of the sealing element 100 can be provided.
[0090] The one or more spring elements 124 in particular can be
arranged or is/are arranged in one or more spring element
receptacles 126.
[0091] In particular, one or more dynamic sealing portions 116 can
be pressed against the movable component 106 by means of the one or
more spring elements 124.
[0092] Alternatively or additionally hereto, it can be provided
that one or more static sealing portions 122 can be pressed against
a housing 118 of the high-pressure pump 102 by means of the one or
more spring elements 124.
[0093] Each dynamic sealing portion 116 preferably comprises one,
two or more than two sealing lips 128.
[0094] Each sealing lip 128 is preferably substantially annular and
substantially rotationally symmetrical about the axis of symmetry
108.
[0095] The sealing lips 128 are arranged here preferably at
different spacings from a transverse central plane 130 of the
sealing element 100 running at right angles to the longitudinal
axis 110 of the sealing element 100.
[0096] The sealing element 100 in particular comprises a main body
132, which is formed preferably in one piece from a thermoplastic
material.
[0097] The main body 132 in particular comprises one or more
dynamic sealing portions 116, one or more static sealing portions
122, and one or more spring element receptacles 126.
[0098] The main body 132 by way of example can be produced as
follows.
[0099] By way of example, a blank 134 of the main body 132 can be
produced in an injection molding process.
[0100] The blank 134 of the main body 132 at this point has its
final outer shape only in portions.
[0101] In particular, merely the spring element receptacles 126 are
completed at the time of production of the blank 134.
[0102] By contrast, the sealing portions 116, 122 must be subjected
to a finishing operation in order to complete the main body 132, in
particular by machining, for example CNC processing.
[0103] As is clear in particular from a comparison of FIGS. 1 to 3,
an outer contour can first be processed by way of example, in order
to complete the radially outer static sealing portions 122. A
radially inner processing can then be performed in order to
complete the dynamic sealing portions 116.
[0104] Alternatively, it can be provided that the blank 134 is
produced for example in an injection molding method in such a way
that both the static sealing portions 122 and the spring element
receptacles 126 already have the final outer shape after the
execution of the injection molding process.
[0105] Merely the radially inner region then still has to be
subjected to a mechanical finishing operation in order to complete
the dynamic sealing portions 116.
[0106] In particular, the main body 132 and thus the entire sealing
element 100 can be produced particularly efficiently and
economically by a combination of production of the blank 134 in a
high-pressure process and/or a high-temperature process, for
example an injection molding process, on the one hand and only
partial subsequent processing in order to complete the main body
132 on the other hand.
* * * * *