U.S. patent application number 16/491895 was filed with the patent office on 2020-01-09 for end plate, filter element, filter system and method for filtering liquid.
The applicant listed for this patent is FSP Fluid Systems Partners Holding AG. Invention is credited to Roland KRAMER, Valentin PICHLMAIER.
Application Number | 20200009483 16/491895 |
Document ID | / |
Family ID | 62222589 |
Filed Date | 2020-01-09 |
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United States Patent
Application |
20200009483 |
Kind Code |
A1 |
PICHLMAIER; Valentin ; et
al. |
January 9, 2020 |
END PLATE, FILTER ELEMENT, FILTER SYSTEM AND METHOD FOR FILTERING
LIQUID
Abstract
An end plate for filter material for filtering a liquid,
particularly a hydraulic oil, having a through opening for filtered
liquid, which is surrounded by a sealing ring for a connecting
piece, and a cover for the filter material. The sealing ring
delimits a free space for accommodating an anti-rotation lock of a
switch and/or a bypass valve of a filter system. Furthermore, a
filter element, a filter system and a method for filtering liquid
are also disclosed.
Inventors: |
PICHLMAIER; Valentin;
(Bretten, DE) ; KRAMER; Roland; (Hambrucken,
DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
FSP Fluid Systems Partners Holding AG |
Baar |
|
CH |
|
|
Family ID: |
62222589 |
Appl. No.: |
16/491895 |
Filed: |
May 7, 2018 |
PCT Filed: |
May 7, 2018 |
PCT NO: |
PCT/EP2018/061724 |
371 Date: |
September 6, 2019 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B01D 35/143 20130101;
B01D 2201/347 20130101; B01D 35/147 20130101; B01D 2201/4076
20130101; B01D 29/13 20130101; B01D 27/08 20130101; B01D 35/30
20130101; F15B 21/041 20130101; B01D 2201/295 20130101; B01D 29/21
20130101 |
International
Class: |
B01D 27/08 20060101
B01D027/08; B01D 29/13 20060101 B01D029/13 |
Foreign Application Data
Date |
Code |
Application Number |
May 9, 2017 |
DE |
10 2017 109 924.7 |
Claims
1. An end plate for filter material for filtering a liquid,
particularly a hydraulic oil, having a through opening for filtered
liquid, which is surrounded by a sealing ring for a connecting
piece, and a cover for the filter material, wherein the sealing
ring delimits a free space for accommodating an anti-rotation lock
a switch and/or a bypass valve of a filter system.
2. The end plate according to claim 1, wherein the free space forms
an accommodating pocket, which extends between the sealing ring and
the cover and has a base.
3. The end plate according to claim 1, wherein the annular space,
the accommodating pocket in particular, is of annular
construction.
4. The end plate according to claim 1, wherein the cover has an
inner ring, wherein the accommodating pocket is constructed between
the sealing ring and the inner ring.
5. The end plate according to claim 4, wherein the inner ring forms
a positioning ring for a support tube.
6. The end plate according to claim 1, wherein the free space has a
depth in the axial direction with respect to the longitudinal
extent of the sealing ring, which at least corresponds to the
penetration depth of the anti-rotation lock.
7. The end plate according to claim 6, wherein the sealing ring has
an upper edge, wherein the depth of the free space is at least 5
mm, particularly at least 10 mm, in particular at least 15 mm from
the upper edge of the sealing ring.
8. The end plate according to claim 1, wherein the free space has a
width in the radial direction starting from the sealing ring, which
is at least 2 mm.
9. A filter element for filtering a liquid, having an end plate
according to claim 1 and a filter material which is arranged on the
cover and surrounds the through opening at the circumference
thereof.
10. The filter element according to claim 9, wherein a support tube
is arranged on the inner side of the filter material and connected
to the end plate.
11. A filter system having a filter element according to claim 9, a
filter housing, in which the filter element is arranged, and a
filter head with connections, which is connected to the filter
housing, wherein the filter head has an anti-rotation lock, which
is connected to a switch and/or a bypass valve, wherein the filter
head and the free space of the end plate form an interface.
12. The filter system according to claim 11, wherein the bypass
valve in the switched state connects the inlet side of the filter
head and the outlet side of the filter head.
13. The filter system according to claim 11, wherein the switch
comprises a reed contact for generating a signal for a
contamination indicator.
14. A method for filtering liquid, in which liquid to be filtered
is supplied to a filter system according to claim 11, filtered in
the filter material and discharged through the through opening of
the end plate as filtered liquid, wherein the switch and/or the
bypass valve is actuated from a differential limit pressure between
the liquid to be filtered and the filtered liquid.
Description
[0001] The invention relates to an end plate for filter material
for filtering a liquid, particularly a hydraulic oil with the
features of the preamble of claim 1. An end plate of this type is
known for example from DE 10 2013 106 264 A1. The invention further
relates to a filter element for filtering a liquid, a filter system
and a method for filtering liquid.
[0002] Hydraulic systems are used for example in construction
machines, agricultural machines, machine tools or processing
machines. The hydraulic oil used in hydraulic systems is usually
filtered. The filter elements used for this absorb the dirt
particles from the hydraulic oil and must be replaced after a
certain time.
[0003] In this context, DE 10 2013 106 264 A1 describes a filter
element for filtering a liquid, with an end plate, which is divided
into two parts and has a fixed and a movable plate part, as a
result of which the replacement of the filter element is
facilitated. A further filter element is known from EP 2 092 970
A1. The known filter elements do not make it possible to
automatically determine the degree of contamination of the filter
material.
[0004] The invention is based on the object of specifying an end
plate for filter material, for filtering a liquid, which allows the
use of a contamination indicator and/or a bypass valve in a filter
element or a filter system with such a filter element. The
invention is further based on the object of specifying a filter
element, a filter system and a method for filtering liquid.
[0005] According to the invention, the object is achieved with
regards to the end plate by means of the subject matter of claim 1.
With regards to the filter element, the filter system and the
method for filtering liquid, the object is achieved according to
the invention by means of the subjects of claims 9, 11 and 14.
[0006] The invention is based on the idea of specifying an end
plate for filter material for filtering a liquid, particularly a
hydraulic oil, having a through opening for filtered liquid, which
is surrounded by a sealing ring (20) for a connecting piece, and a
cover for the filter material. The sealing ring delimits a free
space for accommodating an anti-rotation lock of a switch and/or
bypass valve of a filter system.
[0007] The invention has the advantage that the anti-rotation lock
moves in free space during the actuation of the switch and/or the
bypass valve, i.e. can be moved into the free space or out of the
free space. The anti-rotation lock is used to guide the switch
and/or the bypass valve in a predetermined position in the filter
head, so that for example an optimum flow behaviour of the bypass
valve or the optimum position of the switching components of the
switch is achieved during mounting and during operation. The bypass
valve and/or the switch require a minimum travel for actuation and
correct mode of action. The free space of the end plate according
to the invention means that the anti-rotation lock is effective
over the entire travel without the anti-rotation lock colliding
with the end plate. In the maximum position, for example in the
rest position of the switch and/or the bypass valve, the
anti-rotation lock can on the one hand dip completely into the free
space of the end plate. On the other hand, a sufficiently large
adjustment path is available for actuating the switch and/or the
bypass valve, in which the anti-rotation lock guides or holds the
switch and/or the bypass valve in the desired position.
[0008] The delimiting of the free space by the sealing ring
provides the design prerequisite for making the filter system
compact, because the anti-rotation lock can be arranged in the
vicinity of the sealing ring, specifically on the sealing ring.
This means that the anti-rotation lock can be arranged close to the
through opening in the mounted state. The sealing ring forms the
inner wall of the free space and seals against the outlet
connection in the mounted state.
[0009] The sealing ring is preferably constructed in one piece with
the end plate.
[0010] Therefore, the end plate according to the invention makes it
possible not only to equip a filter system with a switch and/or a
bypass valve, but even to use a switch and/or bypass valve, which
require a particularly large travel. The switch can be used in
order to indicate a particular degree of contamination of the
filter element. Instead of the switch or in addition to the switch,
the end plate can be used with a bypass valve, which allows a
safety function, for example switching off the filter function,
when a particular degree of contamination is reached.
[0011] The end plate is marketable as such and is therefore
disclosed and claimed independently of the filter element. In
addition, the end plate is disclosed and claimed in connection with
the filter element. The end plate forms part of the filter
element.
[0012] In the installed state, the end plate functions as the
interface of the filter element to the filter system, in which the
filter element is used. In this case, the end plate is used on the
one hand to transfer the filtered liquid into the filter head of
the filter system. On the other hand, the end plate is used to
enable the switch function or bypass functions of the filter head.
To this end, the free space for the anti-rotation lock according to
the invention is provided in the end plate. The anti-rotation lock
as such does not form part of the end plate but interacts with the
same in the installed state. The anti-rotation lock is part of the
filter head or the components integrated into the filter head,
specifically of the switch and/or the bypass valve.
[0013] Preferred embodiments of the invention are indicated in the
dependent claims.
[0014] In a preferred embodiment, the free space is constructed as
an accommodating pocket, which extends between the sealing ring and
the cover and has a base. The anti-rotation lock is arranged in the
free space between the sealing ring and the cover. This embodiment
has the advantage that a structurally beneficial movement direction
of the switch and/or the bypass valve, specifically in the axial
direction of the filter element or along the flow direction of the
liquid, is possible due to the end plate. The invention is not
limited to end plates through which axial flow is possible. Other
geometries of the end plate are possible. The accommodating pocket
has the further advantage that the accommodating pocket has a base,
so that the filter space adjoining the end plate is sealed.
[0015] The accommodating pocket is preferably of annular
construction. On the one hand, this has the advantage in terms of
production technology, that the end plate can for example be
constructed as an injection-moulded part with flow paths of
virtually equal length. On the other hand, the end plate is simple
to mount, as it is not necessary to align the end plate relatively
to the anti-rotation lock.
[0016] In a further preferred embodiment, the cover has an inner
ring, wherein the accommodating pocket is constructed between the
sealing ring and the inner ring. The inner ring allows an optimal
utilization of the overall height of the filter element, as the
axial end of the filter material can be arranged in the region of
the inner ring and therefore higher than the base of the
accommodating pocket, particularly at the same height as the
accommodating pocket.
[0017] The height position of the base or of the axial end of the
filter material relates to the longitudinal extent of the filter
element.
[0018] The inner ring may form a positioning ring for a support
tube and consequently has a dual function, as the inner ring forms
the outer wall of the free space or the accommodating pocket and
positions the support tube. Also, in this embodiment, the inner
ring is constructed in one piece with the end plate.
[0019] In a particularly preferred embodiment, the free space has a
depth in the axial direction with respect to the longitudinal
extent of the sealing ring, which at least corresponds to the
penetration depth of the anti-rotation lock into the free space.
Penetration depth is understood to be the distance by which the
anti-rotation lock is moved into the free space. This embodiment is
advantageous in connection with the accommodating pocket in
particular, because in this manner, the anti-rotation lock is
reliably prevented from colliding with the base of the end
plate.
[0020] Preferably, the sealing ring has an upper edge, wherein the
depth is at least 5 mm, particularly at least 10 mm, in particular
at least 15 mm from the upper edge of the sealing ring. Thus, a
sufficiently long adjustment path is available for the
anti-rotation lock.
[0021] Furthermore, the free space, the accommodating pocket in
particular, preferably has a width in the radial direction starting
from the sealing ring, which is at least 2 mm. This has the
advantage that the anti-rotation lock can be constructed in a
sufficiently stable manner.
[0022] With regards to the advantages of the filter element and the
filter system, reference is made to the statements in connection
with the end plate.
[0023] In the case of the filter system, one advantageous
embodiment is that the bypass valve, in the switched state,
connects the inlet side of the filter head and the outlet side of
the filter head. This has the advantage that emergency operation of
the filter system is possible if the filter material has reached a
certain degree of contamination. In this case, it is accepted that
the filter function is at least limited, specifically at most until
the filter material is replaced.
[0024] A further advantageous embodiment of the filter system is
that the switch comprises a reed contact for generating a signal
for a contamination indicator. Reed contacts are known as
hermetically sealed switches which are actuated by means of an
external magnetic field and are very suitable for use in a
hydraulic filter system. Accordingly, the switch comprises a
magnetic element which interacts with the reed contact. The
invention is not limited to certain reed contact types.
[0025] In the context of the method according to the invention, it
is provided that liquid to be filtered is supplied to a filter
system according to the invention, filtered in the filter material
and discharged through the through opening of the end plate as
filtered liquid. The switch and/or the bypass valve are actuated
from a differential limit pressure between the liquid to be
filtered and the filtered liquid. As a result, the degree of
contamination can be indicated and/or emergency operation of the
filter system can be initiated.
[0026] The invention is explained in more detail in the following
with further details and with reference to the attached schematic
drawings on the basis of an exemplary embodiment.
[0027] In the figures
[0028] FIG. 1 shows the section of a filter system with a filter
element and an end plate according to an exemplary embodiment
according to the invention, and
[0029] FIG. 2 shows a detail view of the filter system according to
FIG. 1 in the region of the end plate.
[0030] FIG. 1 shows a filter system 30 for use in a hydraulic
system, for example for a construction machine, agricultural
machine, machine tool or processing machine. The filter system 30
is generally suitable for hydraulic systems in which hydraulic
fluid, particularly hydraulic oil must be filtered.
[0031] The filter system 30 has a filter head 27 with a first
connection 28 and a second connection 29. Hydraulic fluid to be
filtered enters the filter system through the first connection 28
during the use of the filter system 30. The filtered hydraulic
fluid exits the filter system 30 through the second connection 29.
The filter head 27 is connected in a sealed manner, for example
screwed, to a filter housing 26. A filter element 25 is arranged in
the filter housing 26. The filter element 25 comprises a filter
material 10, which effects the filter function during operation.
The invention is not limited to certain filter materials.
Preferably, the filter material 10 is constructed from layers
folded in a star-shaped manner. The superordinate contour or outer
contour of the filter material 10 is cylindrical. In other words,
the macroscopic shape of the filter material 10 is cylindrical and
the microscopic shape of the filter material 10 is star-shaped. The
inner wall of the cylindrical filter material 10 bears against a
support tube 23, which has through openings 31 for the hydraulic
fluid arranged in the longitudinal direction and in a distributed
manner on the circumference. The support tube 23 supports the
filter material 10 in the radial direction.
[0032] In the axial direction, the filter element 25 is delimited
by two end plates 24, 32. The two end plates 24, 32 bear against
the end faces of the filter material 10. The end plates 24, 32, the
support tube 23 and the filter material together form the filter
element 25, which can be handled and marketed as one unit. The
filter element 25 forms a wearing part, which is replaced as a
whole when the filter material 10 is contaminated.
[0033] The end plate 32, which is arranged at the bottom in the
installation direction of the filter element 25, is closed and
seals the interior of the support tube 23 and the filter material
10 in the filter housing 26 downwards. The end plate 24, which is
arranged at the top in the installation direction of the filter
element 25, has a through opening 11, through which the filtered
hydraulic oil or, in general, the filtered hydraulic fluid exits
the filter element 25. The through opening 11 is arranged centrally
in the end plate 24, i.e. in the middle. It is also conceivable
that the through opening 11 is arranged eccentrically. In the
example according to FIG. 1, the filter material 10, the support
tube 23 and the through opening 11 are arranged coaxially. A
different arrangement of these components is possible.
[0034] The upper end plate 24 furthermore has a cover 12, against
which, in the installed state, the filter material 10, specifically
the end face of the filter material 10 bears. The cover 12 has an
annular disc 43, which is arranged coaxially to the through opening
11. The cover furthermore has an inner ring 21 and an outer ring
33, which are connected to the annular disc 43 in each case. The
inner ring 43 and the outer ring 33 are arranged coaxially and,
with the disc 43, form an annular receptacle for the axial end of
the filter material 10. The inner ring 21 and the outer ring 33
overlap the filter material 10 at least to some extent.
[0035] A plurality of spacers 34 are arranged at the outer ring 33,
for example in the form of lugs, which position the filter element
25 in the housing in the filter housing 26 in such a manner that an
annular gap is formed between the filter material 10 and the inside
of the filter housing 26.
[0036] Other geometries of the end plate 24 are possible.
[0037] During operation, the hydraulic oil to be filtered flows
through the first connection 28 into the filter head 27 and from
there radially outwards, past the upper end plate 24 into an
annular gap between the filter element 25 and the filter housing
26. From there, the hydraulic oil flows through the filter material
10 in the radial direction, flows through the support tube 23 and
from there is conveyed in the cleaned state through the through
opening 11 back into the filter head 27 again. There, the cleaned
hydraulic oil exits through the second connection 29.
[0038] The upper end plate 24 is illustrated enlarged in FIG.
2.
[0039] There it can be seen that a free space 13 is formed between
the through opening 11 and the cover 12, specifically the inner
ring 21 of the cover 12, which, in the installed state,
accommodates an anti-rotation lock 14 of a switch 15 and/or a
bypass valve 16 of the filter head 27. The anti-rotation lock 14 is
constructed in the example according to FIG. 2 as a pin-shaped
projection or protrusion of the switch 15 or the bypass valve 16.
The anti-rotation lock 14 protrudes in the installed state over the
disc 43 of the cover 12 in the axial direction of the filter
element 25. The anti-rotation lock 14 and the free space 13 are
flush in the axial direction, so that the anti-rotation lock 14 can
dip into the free space 13 when the switch 15 or the bypass valve
16 is in the rest position illustrated in FIG. 2. To this end, the
depth of the free space 13, i.e. the extent of the free space 13 in
the axial direction of the filter element 25 is dimensioned such
that the anti-rotation lock 14 can be moved into the free space 13
completely without colliding with the end plate 24. Specifically,
the section of the anti-rotation lock 14, which protrudes in the
axial direction over the cover 12 or projects into the filter
element 25, is accommodated in the free space 13 completely.
[0040] The free space 13 is constructed as an accommodating pocket
17, which extends parallel to the flow direction of the liquid
through the through opening 11. In other words, the accommodating
pocket 17 extends in the axial direction of the filter element 25.
The accommodating pocket 17 has a base 19, which downwardly
delimits the accommodating pocket 17, i.e. delimits and seals
towards the interior of the support tube 23. This means that the
cleaned liquid exits entirely through the through opening 11 and
the dirty side is separated from the clean side of the filter
system 30. The accommodating pocket 17 is of annular construction,
so that during the mounting of the end plate, it is not necessary
to determine the position thereof in the circumferential direction
with respect to the anti-rotation lock 14.
[0041] The sealing ring 20 and the inner ring 21 are arranged
coaxially and extend in the longitudinal direction of the filter
element 25. The sealing ring 20 adjoins the through opening 11 and
is used on the one hand to accommodate and seal a connecting piece
22 of the filter head 27. On the other hand, the sealing ring 20
forms the inner wall of the accommodating pocket 17. The inner ring
21 adjoins the annular disc 43 of the cover 12 and extends
substantially parallel to the sealing ring 20. The inner ring 21 is
used to position the support tube 23 at least during mounting. In
addition, the inner ring 21 forms the outer wall of the
accommodating pocket 17.
[0042] The accommodating pocket 17 can also be understood as the
annular gap between the cover 12 and the through opening 11, which
annular gap is closed at the bottom, i.e. in the direction of the
lower end plate 32.
[0043] On the side of the end plate 24 facing away from the
connecting piece 22, a plurality of axial ribs 35 are arranged on
the circumference of the through opening 11, which axial ribs
extend into the interior of the support tube 23 in the installed
state.
[0044] As can be seen further in FIG. 2, the filter head 27 has a
switch and valve unit 36, which comprises a switch 15 and a bypass
valve 16 as an integrated component. It is also possible to
construct the switch 15 and the bypass valve 16 as separate
components with their own anti-rotation lock 14 in each case. The
accommodating pocket 17 can accommodate a plurality of
anti-rotation locks in a distributed manner on the circumference.
It is also possible to provide only one switch 15 or only one
bypass valve 16 in the filter head 27.
[0045] In the example according to FIG. 2, the anti-rotation lock
14 is arranged as a pin-shaped projection or protrusion on a valve
body 37 of the bypass valve 16. The anti-rotation lock 14 and the
valve body 37 are preferably constructed in one piece. The valve
body 37 is constructed cylindrically. The anti-rotation lock 14 is
arranged eccentrically with respect to the valve body 37,
specifically on the circumference of the valve body 37. This has
the advantage that the anti-rotation lock 14 can be arranged close
to the through opening 11.
[0046] The valve body 37 has a piston 18, which is guided in a
slidable manner in the filter head 27.
[0047] The bypass valve 16, specifically the valve body 37, has a
plurality of flow openings, which are arranged in a distributed
manner on the circumference of the bypass valve 16 or the valve
body 37. In the rest state according to FIG. 2, the flow openings
are closed, so that the clean side and the dirty side of the filter
system 30 are separated.
[0048] The bypass valve 16 has an axial guide 38, for example in
the form of guide ribs, which encompass a coaxially arranged pin 39
of the switch 15. The pin 39 is connected to a switch component 40,
which is mounted securely in the filter housing 27 and which
contains the electronics of the switch 15. The axial guide 38 of
the bypass valve 16 is connected to a magnetic element 41, which
can be moved on the pin 39 in the axial direction together with the
bypass valve 16, when a corresponding differential limit pressure
is reached. As a result, the switch 15 is actuated. A spring 42 is
arranged between the valve body 37 and the fixedly arranged switch
component 40, which spring ensures that the bypass valve 16 and the
switch 15 remain in the rest position until the differential limit
pressure is reached at a certain degree of contamination of the
filter element 25. The reed contact itself can be open or closed in
the rest position.
[0049] The anti-rotation lock 14 blocks a movement in the
circumferential direction of the valve body 37 or in general of the
bypass valve 16, so that the valve body 37 can essentially only be
moved in the axial direction of the filter element 25. To this end,
the anti-rotation lock 14 is in engagement with the filter head,
for example by means of a corresponding groove in the filter head
27.
[0050] As the anti-rotation lock 14 protrudes in the direction of
the filter element 25 over the valve body 37, it is achieved that
the anti-rotation lock 14 remains in engagement with the filter
housing 27, even if the bypass valve 16 or the switch 15 are
actuated. Different switching points of the bypass valve 16 and the
switch 15 can be set by means of the length of the anti-rotation
lock 14. For example, the switch 15 may switch already at a lower
differential limit pressure than the bypass valve 16 or vice
versa.
[0051] The filter system according to FIGS. 1 and 2 functions as
follows during use.
[0052] Hydraulic oil to be filtered is supplied to the filter
element 25 through the first connection 28, which hydraulic oil
flows through the filter material 10 in the radial direction. From
the interior of the support pipe 23, the cleaned hydraulic oil
passes through the through opening 11 back into the filter head 27
and from there through the second connection 29 back into the
hydraulic system. With an increasing degree of contamination of the
filter material 10, the back pressure in the region of the first
connection 28 increases, which connection is fluidly connected via
an annular space to the bypass valve, so that the bypass valve 16
is loaded with the corresponding pressure. When the differential
pressure consequently created between the dirty side and the clean
side of the filter system 30 exceeds a certain limit value, which
results from the spring force of the spring, the bypass valve 16 is
actuated, i.e. moved out of the rest position. In this case, the
anti-rotation lock 14 is also moved in the axial direction, which
remains in engagement with the filter housing 27 during the
travelling movement of the bypass valve 16 and thus positions the
bypass valve 16 and the switch 15 in the circumferential direction.
The magnetic element 41 is entrained in the process, so that the
switch 15 is actuated and indicates the degree of contamination. If
the degree of contamination increases further, the bypass valve 16
is switched, so that the flow openings in the bypass valve 16 are
enabled and the clean side is connected to the dirty side,
bypassing the filter element 25 (bypass).
[0053] As soon as the contaminated filter element 25 has been
replaced with a new filter element 25, the back pressure drops and
the bypass valve and the switch 15 return to the rest position. In
this case, the anti-rotation Lock 14 again dips into the free space
13 of the end plate 24.
REFERENCE LIST
[0054] 10 Filter material [0055] 11 Through opening [0056] 12 Cover
[0057] 13 Free space [0058] 14 Anti-rotation lock [0059] 15 Switch
[0060] 16 Bypass valve [0061] 17 Accommodating pocket [0062] 18
Piston [0063] 19 Base [0064] 20 Sealing ring [0065] 21 Inner ring
[0066] 22 Connecting piece [0067] 23 Support tube [0068] 24 (Upper)
end plate [0069] 25 Filter element [0070] 26 Filter housing [0071]
27 Filter head [0072] 28 First connection [0073] 29 Second
connection [0074] 30 Filter system [0075] 31 Through openings
[0076] 32 (Lower) end plate [0077] 33 Outer ring [0078] 34 Spacer
[0079] 35 Axial ribs [0080] 36 Switch and valve unit [0081] 37
Valve body [0082] 38 Axial guide [0083] 39 Pin [0084] 40 Switch
component [0085] 41 Magnetic element [0086] 42 Spring [0087] 43
Disc
* * * * *