Field of Invention

The present application relates to a filter assembly and method that includes using a filter element retention lock.

Background

Various applications and systems implement filter assemblies, such as hydraulic systems in aerospace applications. Some applications have limited space for installing and accommodating the filter assembly. Due to a tight installation clearance between adjacent objects and a filter housing that houses the filter element, the filter element and the filter housing must remain connected during removal of the filter assembly from the filter manifold. Removal of the filter assembly from the filter manifold may be required for maintenance or replacement of the filter assembly components. Consequently, if only the filter housing is removed from the filter manifold, the filter element may remain attached to the manifold such that the housing may collide with the filter element due to space constraints.

Prior attempts to retain a connection between the filter housing and the filter element include using locking mechanisms that are arranged at an upper opening of the filter housing. However, the prior attempts are disadvantageous in that the components comprising the locking mechanisms are arranged in the flow path of fluid through the filter assembly, such that flow may be negatively impacted.

Summary of Invention

The present application is directed toward a filter assembly having a retention lock arranged at an end of the filter assembly that is opposite an attachment end at which the filter assembly is attached to a filter manifold. The retention lock is formed as a protrusion that is received in a recess during a relative rotation between a filter element and a housing of the filter assembly. During removal of the filter assembly from the filter manifold, the housing is rotated relative to the filter element such that the protrusion of the retention lock engages into an undercut of the recess to secure the filter element and the housing for removal of the filter assembly as a unit from the filter manifold. The filter element and the housing are disengaged when the filter assembly is rotated in an opposite direction and the protrusion is disengaged from the undercut.

Using the retention lock is advantageous in that the filter element and the housing are locked at a location in which the retention lock does not interrupt the flow path through the filter assembly. The retention lock is also formed as part of the filter assembly, such that locking the filter element and the housing occurs simultaneously with the rotation of the filter assembly during removal of the filter assembly from the filter manifold. The recess and the retention lock are formed such that the locking engagement only occurs in one rotational direction of the filter assembly, and the locking engagement is disengageable in an opposite rotational direction.

The recess is formed in either an end cap of the filter element or in the housing, and the retention lock is attached to the other of the end cap or the housing. The retention lock may be integrally formed as a single monolithic component with the end cap or the housing, or the retention lock may be fixedly secured to the end cap or the housing. The undercut of the recess is formed to be matingly engaged by a radially protruding surface of the retention lock when the retention lock is moved to the engaged position during the relative rotation between the filter element and the housing. The filter assembly is formed such that the relative rotation is less than a full circular range of rotation.

According to an aspect of the disclosure, a filter assembly includes a filter element having a first end connectable to a fluid port and a second end opposite the first end, a housing that supports the filter element, and a retention lock attached to one of the filter element or the housing at the second end of the filter element, the retention lock being movable between a disengaged position and an engaged position in which the retention lock couples the filter element and the housing for uniform movement, the retention lock being movable by relative rotation between the filter element and the housing. According to another aspect of the disclosure, a filter system includes a filter manifold, and a filter assembly having a first end removably attachable to the filter manifold, the filter assembly comprising a filter element, a housing that supports the filter element, and a retention lock attached to one of the filter element or the housing at a second opposite end of the filter assembly relative to the filter manifold, the retention lock being movable between a disengaged position and an engaged position in which the retention lock couples the filter element for detachment of the filter assembly as a unit from the filter manifold, the retention lock being movable by relative rotation between the filter element and the housing when the filter assembly is rotated relative to the filter manifold.

According to still another aspect of the disclosure, a method of manufacturing a filter assembly includes arranging a retention lock at an end of the filter assembly opposite an attachment end of the filter assembly that is engageable with a fluid port, securing the retention lock to one of a filter element or a housing that receives the filter element of the filter assembly, forming a recess including an undercut in the other of the filter element or the housing, and inserting the filter element into the housing whereby the retention lock is received in the recess, wherein relative rotation between the filter element and the housing in a first rotational direction enables engagement of the retention lock with the undercut to couple the filter element and the housing, wherein relative rotation in a second opposite rotational direction enables disengagement of the retention lock to uncouple the filter element and the housing.

Other systems, devices, methods, features, and advantages of the present invention will be or become apparent to one having ordinary skill in the art upon examination of the following drawings and detailed description. It is intended that all such additional systems, methods, features, and advantages be included within this description, be within the scope of the present invention, and be protected by the accompanying claims.

Brief Description of the Drawings Fig. 1 is a drawing depicting a sectional view of a filter system including a filter assembly attached to a filter manifold.

Fig. 2 is a drawing depicting a sectional view of a retention lock that secures a filter element and a housing of the filter assembly of Fig. 1.

Fig. 3 is a drawing depicting a sectional view of a recess of the retention lock of Fig. 2.

Fig. 4 is a drawing depicting the filter assembly of Fig. 1 during an initial installation of the filter element and the housing.

Fig. 5 is a drawing depicting the filter assembly of Fig. 1 when the retention lock is engaged in a recess during element assembly removal from the filter manifold.

Fig. 6 is a drawing depicting the filter assembly during installation of the filter assembly to the filter manifold.

Fig. 7 is a drawing depicting a bottom view of an exemplary embodiment of a recess formed in an end cap of the filter element.

Fig. 8 is a drawing depicting a top view of an exemplary embodiment of the retention lock.

Fig. 9 is a drawing depicting a side view of the retention lock of Fig. 8.

Detailed Description

The present application is directed toward a filter assembly including a filter element having a filtration media and a housing that supports the filter element.

The filter assembly is configured to be attached to a fluid port such that the filter element receives a fluid to be filtered. Any suitable manifold including at least one fluid port may be connectable with the filter assembly. The manifold may include a filter head. The configuration of the manifold and fluid ports may be dependent on the application for the filter assembly. Many different applications may implement the filter assembly and method described herein. For example, a hydraulic system in an aerospace application may be a suitable application.

Referring to Fig. 1 , an exemplary filter system 20 including a filter assembly 22 is shown. The filter system 20 includes a filter manifold 24 that is arranged in or affixed to an envelope 26. The envelope 26 may be part of any suitable platform, such as a stationary or moving platform, including land, air, and space vehicles.

The filter manifold 24 includes at least one fluid port 28, 30 that is fluidly connected to a fluid source 32. The fluid source 32 may be arranged in the envelope 26 or anywhere on the platform in which the filter system 20 is implemented. The envelope 26 may have any suitable dimensions, and the envelope 26 may encompass a compact area within the platform in which space is constrained.

The filter manifold 24 may be in the form of a filter head that includes an inlet fluid port 28 and an outlet fluid port 30 fluidly connected to the fluid source 32. The filter assembly 22 is arranged downstream the inlet fluid port 28 and upstream the outlet fluid port 30. A connection port 38 is also formed in the filter manifold 24 and configured to receive the filter assembly 22 for attaching the filter assembly 22 to the filter manifold 24. In an exemplary embodiment, the fluid ports 28, 30 may be arranged above the connection port 38 such that the filter assembly 22 is connected at a bottom portion of the filter manifold 24. The filter assembly 22 is thus configured to receive and discharge fluid at the end of the filter assembly 22 attached to the filter manifold 24.

The filter manifold 24 may further include any suitable valve-type components that are arranged in the flow path between the inlet fluid port 28 and the outlet fluid port 30. As shown in Fig. 1 , the filter manifold 24 may include a diaphragm 40 that is attached to the filter assembly 22 and biased by a spring 42. The diaphragm 40 is arranged in the flow path downstream from the inlet fluid port 28 and upstream the filter assembly 22. Many other manifold structures or fluid port structures may also be connectable to the filter assembly 22. The structure may be dependent on the application and/or envelope 26 in which the filter system 20 is arranged.

The filter assembly 22 includes a filter element 34 and a housing 36 that is configured to receive and support the filter element 34. The filter element 34 includes a longitudinally extending body of filter media having sidewalls 44. Any suitable filtration media may be used, and the filtration media material may be dependent on the application and fluid to be filtered. The filter element 34 may have any suitable shape, such as a cylindrical shape.

The housing 36 radially surrounds the filter element 34 and may have any suitable shape, such as a shape that is complementary to the shape of the filter element 34. The housing 36 is attached to the filter manifold 24 and may be elongated to extend along an entire length of the filter element 34 from the filter manifold 24. The filter element 34 may be a cartridge-type filter. Any suitable manufacturing process and materials may be used to form the housing 36. Plastic or metal materials may be used. A flow gap 46 is radially formed between the housing 36 and the sidewalls 44 of the filter element 34, with the flow gap 46 extending axially along the length of the filter element 34. The inlet fluid port 28 is fluidly connected with the flow gap 46 via a fluid chamber 48 that is defined in the filter manifold 24 and in which the diaphragm 40 is movable.

A first end 50 of the filter assembly 22 is attached to the filter manifold 24 such that the corresponding first ends of the housing 36 and the filter element 34 are attached to the filter manifold 24. The first end 50 may be an upper end or top end of the filter assembly 22. The filter element 34 may have a first end cap 52 arranged at the first end of the filter element 34 and attached to the sidewalls 44. In an exemplary embodiment of the filter system 20, the first end cap 52 may be attached to the diaphragm 40 of the filter manifold 24, and an o-ring seal 54 may be arranged therebetween. The first end of the housing 36 may abut against the chamber 48, the diaphragm 40, and the first end cap 52 such that the filter assembly 22 is securely engaged against the filter manifold 24 when assembled.

The flow gap 46 may be formed radially outside the location where the first end cap 52 and the diaphragm 40 are engaged. In an exemplary operation of fluid flow through the filter system 20, fluid flows from the inlet fluid port 28 into the chamber 48 of the filter manifold 24 containing the diaphragm 40, around the diaphragm 40 and into the flow gap 46. The fluid may flow axially through the flow gap 46 and is received through the sidewalls 44 of the filter element 34 for filtering. The filtered fluid then travels in an upward direction 56 through the filter element 34 toward the filter manifold 24 and the outlet fluid port 30 for exiting the filter system 20.

A second end 58 of the filter assembly 22 is opposite the first end 50 and proximate the filter manifold 24. The second end 58 may be a bottom or lower end of the filter assembly 22. The bottom end of the housing 36 may be formed to have a bowl shape 60 that supports a second end cap 62, or bottom end cap, of the filter element 34. The second end cap 62 may have any suitable shape. For example, the second end cap 62 may have a disk shape with an outer diameter that is greater than an outer diameter of the sidewall 44 of the filter element 34. The sidewall 44 may be supported within the second end cap 62. The first end cap 52 and the second end cap 62 may be formed using any suitable manufacturing process and any suitable material, such as metal or plastic. The end caps 52, 62 may be formed separately and subsequently attached to the sidewalls 44 of the filter element 34.

A retention lock 64 is arranged at the second end 58 of the filter assembly 22 and is configured to couple the filter element 34 and the housing 36 during a relative rotation between the filter element 34 and the housing 36. In an exemplary embodiment, the retention lock 64 is secured to the housing 36 and received in a recess 66 formed in the second end cap 62 of the filter element 34. In an alternative embodiment, the recess may be formed in the housing 36 and the retention lock 64 may be fixed to the filter element 34. Advantageously, the filter element 34 and the housing 36 are fixedly coupled by their relative rotation by way of the retention lock 64 being engageable.

Relative rotation occurs during installation and removal of the filter assembly 22 from the filter manifold 24 in which the filter assembly 22 is rotated relative to the filter manifold 24. The filter assembly 22 may be removed for maintenance or replacement of components in the filter system 20. When the filter assembly 22 is rotated for removal, the relative rotation between the filter element 34 and the housing 36 occurs in the same direction, which simultaneously causes the retention lock 64 to engage and lock the filter element 34 and the housing 36.

Coupling the filter element 34 and the housing 36 is advantageous in that the filter element 34 is prevented from colliding with the housing 36 if the filter element 34 was to remain connected to the filter manifold 24 during removal. Using the retention lock 64 thus enables the filter assembly 22 to be installed in compact envelopes. Arranging the retention lock 64 at the bottom or second end 58 of the filter assembly 22 opposite the filter manifold 24 is further advantageous in that the retention lock 64 is not arranged in the fluid path of the filter assembly 22, such that coupling the filter element 34 and the housing 36 with the retention lock 64 does not require any components that would disrupt fluid flow.

Referring now to Figs. 2 and 3, further details of the filter assembly 22 including the retention lock 64 are shown. The retention lock 64 includes an elongated body 68 and a projection 70 that extends axially and radially relative to the elongated body 68, such that the retention lock 64 may have a bolt shape or T- shape with the elongated body 68 forming the base of the T-shape. Other shapes may be suitable for the retention lock 64 and the recess in which the retention lock 64 is inserted. Any suitable manufacturing processes and materials may be used to form the retention lock 64. Plastic or metal materials may be suitable and the material may be dependent on the application. The retention lock 64 may be formed of the same material as the housing 36.

The elongated body 68 is secured to the housing 36 using any suitable securing mechanism. The housing 36 may include a slot 72 that is complementary in shape to the elongated body 68 such that the elongated body 68 is fitted within the slot 72. The retention lock 64 may be threadedly engaged or press fit into the slot 72. An adhesive material may also be used. Other mechanical fasteners, such as clamps, pins, bolts, screws, or any suitable device may be used to secure the retention lock 64 and the housing 36. In another exemplary embodiment, the retention lock 64 may be formed integrally with the housing 36 as a single monolithic component. In alternative embodiments in which the retention lock 64 is secured to the filter element 34, the retention lock 64 may be integrally formed with the second end cap 62 of the filter element 34.

The projection 70 of the retention lock 64 is received in the recess 66 and includes a radially extending flange 74 that extends radially outwardly relative to a longitudinal axis L of the elongated body 68. A shoulder 76 may also be formed on the projection 70, and the shoulder 70 is engageable against a seat 78 defined by the housing 36 for axially positioning the retention lock 64 relative to the housing 36. The second end cap 62 of the filter element 34 is also seated against the seat 78 and radially surrounds the projection 70. The shoulder 76 may be formed as a radially projecting surface that projects radially outwardly relative to the longitudinal axis L. The radially extending length of the shoulder 76 is less than the radially extending length of the radially extending flange 74 and the shoulder 76 is axially interposed between the elongated body 68 and the radially extending flange 74.

The recess 66 may have a circular shape and is closed at a first or upper end by a radial wall 80 of the second end cap 62. The radial wall 80 is arranged in the filter element 34. An opposing radial wall 82 of the end cap 62 defines a radial opening through which the retention lock 64 extends, such that the recess 66 is open away from the filter element 34 and toward the housing 36 to receive the retention lock 64.

As best shown in Fig. 3, the recess 66 includes at least one undercut 84 that is formed in the recess 66 and retains the radially extending flange 74 of the retention lock 64. More than one undercut may be provided. The radially extending flange 74 is matingly engageable into the undercut 84 when the retention lock 64 is in the engaged position such that the radially extending flange 74 is fixedly secured in the undercut 84 to hold the filter element 34 and the housing 36 together. The undercut 84 may be angular in shape. An angular radial surface 86 of the undercut 84 is defined by the radial wall 82 and opposes a radial end face of the end cap 62 that faces outwardly from the filter element 34.

The undercut 84 is formed along a portion of the recess 66 and along a path of movement for the radially extending flange 74 during a range of relative rotation between the filter element 34 and the housing 36 when the filter assembly 22 is rotated relative to the filter manifold 24 (shown in Fig. 1 ). The range of relative rotation is less than a full circular range of rotation. For example, the range may be between 60 and 110 degrees. The range may be approximately 90 degrees.

Referring in addition to Figs. 4-6, operation of the retention lock 64 is shown. Fig. 4 shows the filter assembly 22 when the filter element 34 and the housing 36 are first assembled together. When the filter element 34 is inserted into the housing 36, the retention lock 64 is disengaged relative to the recess 66. Fig. 5 shows the filter assembly 22 during removal of the filter assembly 22 relative to the filter manifold 24. During removal, the filter assembly 22 is rotated in a first rotational direction 88. When the housing 36 and thus the retention lock 64 are also rotated in the first rotational direction 88, the retention lock 64 engages into the undercut 84 for locking the filter element 34 and the housing 36. Accordingly, the retention lock 64 secures the filter element 34 and the housing 36 simultaneously during removal of the filter assembly 22. The locking thus also occurs only during rotation in the removal direction.

Fig. 6 shows an installation position in which the filter assembly 22 is rotated in a second rotational direction 90 opposite the first rotational direction 88. The second rotational direction 90 may be clockwise and the first rotational direction 88 may be counterclockwise, or vice versa. The second rotational direction 90 is an assembly direction in which the filter assembly 22 is rotated to secure the filter assembly 22 relative to the filter manifold 24, and is an opposite operation as compared with removal of the filter assembly 22. When the filter assembly 22 is rotated in the second rotational direction 90, the retention lock 64 engages into the recess 66 such that the retention lock 64 is rotatable in the recess 66.

Fig. 7 shows a bottom view of an exemplary embodiment of the recess 66 formed in the second end cap 62. The recess 66 including the undercut 84 has an asymmetrical shape about a central axis C of the second end cap 62. The recess 66 may include pockets 92, 93 that protrude radially outwardly from the recess 66. The pockets 92, 93 may be elliptical or circular in shape. Other shapes may be suitable and the shape may be dependent on the shape of the retention lock 64 received in the recess 66.

In an exemplary embodiment, four pockets may be provided. Two pockets 92 may be the same in shape and size and arranged opposite to each other. Two other same pockets 93 may be arranged opposite to each other and perpendicular relative to the two pockets 92. Fewer or more than four pockets 92, 93 may be provided. The pockets 92 receive the retention lock 64 when the filter assembly 22 is rotated in the second rotational direction 90 (shown in Fig. 5). The pockets 92 are formed to be symmetrical about the central axis C of the second end cap 62.

The undercut 84 may include two undercuts that are formed offset to the central axis C and protrudes radially outwardly relative to the pockets 92. The two undercuts are arranged opposite to each other.

In an exemplary embodiment of the second end cap 62 and the recess 66, the undercut 84 has a radius Ri that is less than a radius R20f the second end cap 62. The second end cap 62 and the recess 66 may be sized up or down depending on the application and the size of the filter assembly 22.

Fig. 8 shows a top view of an exemplary embodiment of the retention lock 64 including the elongated body 68 and the radially extending flange 74 of the projection 70. The radially extending flange 74 may be elongated along a length that is longer than a width W. The ends 96 are received in the recess pockets 92 when the filter assembly 22 is rotated in the installation direction, e.g. the clockwise direction of Fig. 6, and in the undercuts 84 when the filter assembly 22 is rotated in removal direction, e.g. the counterclockwise direction of Fig. 5. The radially extending flange 74 is curved along the ends 96 such that the ends 96 are matingly engageable with a complementary contour of the pockets 92 and undercuts 84 of the recess 66.

Fig. 9 shows a side view of the retention lock 64 including the elongated body 68, the radially extending flange 74 of the projection 70, and the shoulder 76 of the projection 70. The retention lock 64 may be formed integrally as a single monolithic component such that the projection 70 and the elongated body 68 are formed together. In other exemplary embodiments, the projection 70 may be formed separately and subsequently attached to the elongated body 68.

The retention lock 64 may include a curved portion 102 arranged between the elongated body 68 and the shoulder 76. An innermost diameter Di of the retention lock 64 is less than an outer diameter D2 of the elongated body 68 which is less than an outer diameter D3 of the projection 70. The outer diameter D3 forms the shoulder 76. An outermost diameter of the projection 70 is the greatest diameter of the retention lock 64 and formed on the radially extending flange 74. The retention lock 64 may have any other suitable shape and may be sized up or down depending on the application and the size of the filter assembly 22. The retention lock 64 may have other shapes such as a square shape, a hook, or any other protrusion that is engageable with a recess.

A filter assembly includes a filter element having a first end connectable to a fluid port and a second end opposite the first end, a housing that supports the filter element, and a retention lock attached to one of the filter element or the housing at the second end of the filter element, the retention lock being movable between a disengaged position and an engaged position in which the retention lock couples the filter element and the housing for uniform movement, the retention lock being movable by relative rotation between the filter element and the housing.

One of the filter element or the housing may include a recess configured to receive the retention lock.

The recess may include an undercut that is matingly engaged by the retention lock when in the engaged position.

The recess may include a pocket that is symmetrical about a central axis of the recess, wherein the undercut is offset relative to the central axis.

The retention lock may have a projection that extends axially into the recess.

The retention lock may have an elongated body secured to one of the filter element or the housing, and the projection protrudes axially and radially relative to the elongated body.

The projection may include a radially extending flange that matingly engages with the undercut when the retention lock is in the engaged position.

The projection may include a shoulder that rests against the filter element or the housing and is arranged between the elongated body and the radially extending flange.

The radially extending flange may engage with the undercut during a first rotational direction of relative rotation and disengages with the undercut during a second opposite rotational direction of relative rotation. The filter element may include an end cap at the second end of the filter element and the recess is formed in the end cap, wherein the retention lock is secured to the housing.

The housing may radially surround the filter element and the end cap may be supported in the housing.

The retention lock may be T-shaped.

The retention lock may be moved to the engaged position during the relative rotation in a first rotational direction and moved to the disengaged position during the relative rotation in a second opposite rotational direction.

The range of relative rotation may be less than a full circular range of rotation.

The range of relative rotation may be between 60 and 110 degrees.

A filter system includes a filter manifold, and a filter assembly having a first end removably attachable to the filter manifold. The filter assembly include a filter element, a housing that supports the filter element, and a retention lock attached to one of the filter element or the housing at a second opposite end of the filter assembly relative to the filter manifold, the retention lock being movable between a disengaged position and an engaged position in which the retention lock couples the filter element for detachment of the filter assembly as a unit from the filter manifold, the retention lock being movable by relative rotation between the filter element and the housing when the filter assembly is rotated relative to the filter manifold.

One of the filter element or the housing includes a recess configured to receive the retention lock, wherein the recess includes an undercut that is matingly engaged by the retention lock when in the engaged position.

The retention lock may have an elongated body secured to one of the filter element or the housing, and a projection that protrudes from the elongated body and is matingly engageable in the undercut.

The retention lock may only moved to the engaged position during the relative rotation in a first rotational direction and moved to the disengaged position during the relative rotation in a second opposite rotational direction, wherein the range of relative rotation is less than a full circular range of rotation.

A method of manufacturing a filter assembly includes arranging a retention lock at an end of the filter assembly opposite an attachment end of the filter assembly that is engageable with a fluid port, securing the retention lock to one of a filter element or a housing that receives the filter element of the filter assembly, forming a recess including an undercut in the other of the filter element or the housing, and inserting the filter element into the housing whereby the retention lock is received in the recess, wherein relative rotation between the filter element and the housing in a first rotational direction enables engagement of the retention lock with the undercut to couple the filter element and the housing, wherein relative rotation in a second opposite rotational direction enables disengagement of the retention lock to uncouple the filter element and the housing.

Although the invention has been shown and described with respect to a certain embodiment or embodiments, it is obvious that equivalent alterations and modifications will occur to others skilled in the art upon the reading and understanding of this specification and the annexed drawings. In particular regard to the various functions performed by the above described elements (components, assemblies, devices, compositions, etc.), the terms (including a reference to a "means") used to describe such elements are intended to correspond, unless otherwise indicated, to any element which performs the specified function of the described element (i.e., that is functionally equivalent), even though not structurally equivalent to the disclosed structure which performs the function in the herein illustrated exemplary embodiment or embodiments of the invention. In addition, while a particular feature of the invention may have been described above with respect to only one or more of several illustrated embodiments, such feature may be combined with one or more other features of the other embodiments, as may be desired and advantageous for any given or particular application.