Note: Descriptions are shown in the official language in which they were submitted.
D-5060 10~7109
The present invention relates generally to a
filter design, and more particularly to an improved modular
construction wherein a plurality of substantially identical
filter head units may be interconnected adjacent to each
other to provide parallel flow through filter elements
mounted within filter bowls, there being one filter element
and one filter bowl secured to each of the filter head units.
It has been recognized in the prior art that it
may be desirable when filtering oil or a hydraulic fluid
to employ a plurality of filtering elements. In one prior
art design a plurality of filter head units may be stacked
adjacent each other, the filter head units permitting
series flow through filter elements carried by the units.
,, It has been recognized that parallel flow through filtering
elements may be more desirable than series flow through
such elements. Various proposals have been made in the
prior art for providing for parallel flow through a plura-
ity of elements, but none of these prior art proposal,s
'have gained wide spread commercial acceptance. One design
permits parallel flow through a pair of filter elemèhts,
but it is not possible to stack the filter head units to
which the elements are connected in such a manner that
three or more filtering elements can be utilized. Other
prior art discloses a modular construction wherein two or
more filter elements may be connected to two or more filter
head unit's, but this construction has not gained wide spread
commercial acceptance due to the difficulties in manufactur-
ing the individual filter head units.
D-5060 1~87109
Therefore, it is an object of the present
invention to provide a novel filter head unit to which a
filter element and filter bowl may be secured, the filter
head unit being so constructed that it can be readily
secured to other like filter head units to provide for
parallel flow through two or more filtering elements, the
filter head units being so designed that they can be
readily manufactured and assembled adjacent to each other.
~ .
The foregoing object and other objects and advan-
tages of the present invention are accomplished by providing
a filter head unit including a member having first and
second opposed generally planar end surfaces interconnectable
with corresponding surfaces of like filter head units to
; permit stacking of the filter head units, a side surface
adapted to receive one end each of a filter element and a
filter bowl in generally concentric fluid type relationships,
generally parallel inlet and outlet passageways which lie in
a plane generally parallel to the side surface, the inlet
; and outlet passageways extending between the first and
second end surfaces, a first port extending between the
outlet passageway and the side surface to place the outlet
- passageway in communication with a chamber within the filter
element, and a second port extending between the inlet
passageway and the side surface to place the inlet passage-
way in communication with a chamber surrounding the filter
element. In addition, the filter head unit further includes
a relief valve extending between the inlet and outlet
passageways. The foregoing structure will be described in
greater detail with reference to the accompanying drawings
'
D-5060 10~7~09
in which a preferred form of this invention is illustrated.
Figure 1 is a perspective view showing three
filter head units stacked adjacent each other, each of the
filter head units carrying a filter bowl in which a filter
element is mounted.
Figure 2 is an enlarged sectional view of one of
the filter head units shown in Figure 2.
Figure 3 is a section taken generally along the
line 3-3 in Figure 2.
Figure 4 is a section taken along line 4-4 in
Figure 3, the filter element and bowl being eliminated for
purposes of clarity.
Figure 5 is a section taken generally along the
line 5-5 in Figure 4.
Referring first to Figure 1, a filter assembly is
illustrated which includes three stackable filter head
units which have been secured to each other to provide for
parallel flow through three filter elements, the filter
assembly being indicated generally at 10, and the filter
head units each being indicated generally at 12. Each of
the filter head units 12, as can best be seen from Figures
3 and 4, includes a member 14 having first and second
opposed generally planar end surfaces 16, 18, respectively,
the first and second end surfaces being formed on the
exterior surface of first and second mounting flanges 20,
22, respectively. The first mounting flange 20 is provided
with a plurality of apertures 24 (Figure 5) which extend
through the mounting flange, and the second mounting flange
is provided with a corresponding plurality of threaded
D-5060 ~0~7~09
recesses 26 formed in bosses 28, corresponding apertures
24 and recesses 26 being in alignment with each other.
Fastening means or bolts 30 pass through the apertures
24 and are screwed into the threaded recesses 26 to secure
adjacent filter head units to each other, the head of each
bolt bearing against the inner surface 32 of the flange 20.
Suitable sealing means (not shown) may be disposed between
adjacent surfaces 16, 18.
An array of filter head units which have been
secured to each other are in turn secured to a special
mounting member 34 which is provided with passageways
which are in communication with the inlet and outlet
passageways 36, 38, respectively, of the adjacent filter
head unit. The special mounting member 34 is customarily
disposed between the surface 18 of one of the end filter
head units of an array and a mounting bracket 40. The
bracket 40 is in turn secured in a suitable manner to
appropriate framework 42 of a tractor or the like. The
mounting bracket 40 is also provided with suitable apertures
which permit the special mounting member 34 to be secured
to appropriate inlet and outlet lines (not shown). In a
typical installation the outlet line will extend to a
hydraulic pump, and the inlet line will extend to return
lines and the hydraulic reservoir. The surface 16 of the
other of the end filter head units may receive a closure
plate 44 which blocks the inlet and outlet passageways
36, 38.
The inlet and outlet passageways 36, 38 of each
of the filter head units 12 are formed in the member 14 and
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D-5060 10~09
are generally parallel to each other and extend between
the first and second end surfaces 16, 18. Each of the
inlet and outlet passageways is defined by a generally
cylindrical wall surface 37, 39, respectively, the cylin-
drical wall surfaces being generated about the center lines
46, 48 for the inlet and outlet passageways 36, 38,
respectively. The wall surfaces and the center lines 46, 48
are disposed at right angles to the planar end surfaces 16,
18. The member 14 is provided with side surface means
including inner and outer annular concentric mounting
surfaces 50, 52, respectively. One end 54 of a conventional
cylindrical filter element, indicated generally at 56, is
customarily mounted in fluid type relationship to the inner
annular surface 50, and the open end of a conventional
; cylindrical filter bowl 58 is mounted along the outer
annular mounting surface 52. The filter bowl and filter
element are mounted concentrically about each other and,
when mounted, have a common center line 60. The filter
element 56 and bowl 58 are secured to the filter head unit
in a conventional manner. Thus, a rod 62 is provided, the
rod being concentric with the center line 60, the upper end
of the rod being threaded into a threaded bore 64 on the
upper surface of the filter head unit. A retaining`member
; 66 is pinned or otherwise rigidly secured to the lower end
of the rod 62, a surface of the retaining member bearing
against the lower surface of the bowl to force it into
sealing relationship with the annular surface 52 and an
O-ring 52a as the rod 62 is threaded into its secured
position shown in Figure 2. A spring 68 is disposed-
.
~ S/N 281,548
~0!37109
between the lower inner surface of the bowl 58 and bears against the
lower face of a washer 70, the upper surface of which in turn bears
against the lower surface of the filter to hold the upper end of the
filter in a fluid tight relationship with the inner annular surface 50
and an 0-ring 50a. As can best be seen from Figure 2 the filter element
56 has spaced apart inner and outer cylindrical walls, the inner cylin-
drical wall defining a chamber 72. A second chamber 74 is defined by
the outer surface of the filter element and the inner cylindrical wall
surface of the filter bowl 58. As can best be seen from Figure 2 a
first port 76 extends between the outlet passageway 38 and the side
surface means to place the outlet passageway 38 in communication with
the first chamber 72. Similarly, a second port 78 is provided in the
member 14 which extends between the inlet passageway 36 and the side
surface means to place the inlet in communication with the second
chamber 74. The first port has a generally cylindrical wall surface,
the axis of which is also concentric with the center line 60.
A relief valve, indicated generally at 80, is disposed in a
relief valve passageway 81 extending between the inlet and outlet
passageways 36, 38, which passageway extends to one side of the member
14. The relief valve includes a valve seat 82, a valve plate 84 which
is adapted to bear against the valve seat 82, a machine screw 86 the
head 88 of which is adapted to bear agalnst the plate 84, a nut 90 which
ls received on one end of the screw 86, a support member 92, the screw
86 passing through a central aperture in its support member 92, a
spring 94 disposed between the support member and a
D-5060 ~ ~ ~71Q9
washer 96 which is in turn disposed between the spring 94
and the nut 90. The support member 92 has additional
apertures which are circumferentially spaced
about the central aperture, these additional apertures
permitting the flow of oil from the inlet passage to the
outlet passage in the event that the filter elements 56
become clogged.
It is a feature of this invention that the filter
heads are so designed that they can be easily manufactured,
as for example, by a die casting process. In accordance
with this feature it is necessary that the various portions
of each of the members 14 be related to each other in such
a manner that the member 14 can be easily die cast. In
addition, various relationships must also be maintained so
identical filter head units can be easily stacked adjacent
each other. Thus, the side surface means, namely the inner
and outer annular mounting surfaces 50, 52 must lie in
planes which are perpendicular to the end surfaces 16 and 18
so that when the units are assembled adjacent to each other
one filter bowl will not interfere with another filter bowl.
In order to provide for ease of manufacture and facility of
stacking adjacent units the passageways 36, 38 should also
be disposed at right angles to the end surfaces 16, 18. In
order to facilitate the die casting of the structure the
; passageways 36, 38 should lie in a plane parallel to the
plane to the surfaces 50, 52. In addition, the center line
60 of the filter element should intersect the center line 48
of the outlet passageway 38. In accordance with these
relationships the plane established by the cen-ter line 60,
: D-5060 10~71Q9
which is the center.line for the filter element 56, the
filter bowl 58, and the first port 76 and also the center
line 48 for the outlet passageway 38 is at right angles to
the plane established by the center lines 46 and 48 for the
inlet and outlet passageways and is in addition at right
angles to the planar end surfaces 16, 18. Similarly, the
plane established by the center lines 46, 48 is also at
right angles to the planar end surfaces 16, 18.
While a preferred stru.cture in which the princi-
ples of the present invention have been incorporated is
shown and described above, it is to be understood that the
inventlon is not to be limited to the particular details, ~.
shown and described above, but that, in fact, widely
differing means may be employed in the practice of the
broader aspects of this invention.
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