TECHNICAL FIELD

The invention relates to a filter arrangement for cleaning a fluid. More specifically, the filter arrangement is adapted for cleaning a fluid for an internal combustion engine, wherein the fluid may be a liquid such as a lubricating oil or fuel or a gas such as air. Such filter arrangements may be provided onboard vehicles and in other applications containing transport systems to remove unwanted solids or other contaminants from the fluid. The filter insert may be called filter cartridge or filter module. The filter arrangement comprises a filter housing, which may be non-removably attached to the internal combustion engine. The filter housing may be cup-shaped with an upper open, access end for receipt of the filter insert. The filter housing encompasses at least one inlet for raw fluid to be filtered, which empties into a raw side of the filter housing, and an outlet, which starts at a clean side of the filter housing, for filtered clean fluid. The inlet and outlet may be provided in a lower portion of the filter housing. The filter housing defines a longitudinal axis, along which the filter insert can be inserted into the filter housing and removed from it. The filter arrangement may further comprise a removable lid for closing the open end of the filter housing during operation. The lid may also be called cover or cap.

The invention can be applied in an internal combustion engine, such as a diesel engine, for heavy-duty vehicles, such as trucks, buses and construction equipment. Although the invention will be described with respect to a diesel engine for a truck, the invention is not restricted to this particular application, but may also be used in other types of engines and for other types of vehicles, such as passenger cars. Further, the filter arrangement will be described below in an application for filtering oil, but may be used also in other applications for filtering other fluids.

BACKGROUND

There is normally a need for an engine oil filter in the engine oil system, both to carry initial dirt from production, but also to remove wear particles during engine operation. The oil filter is normally subjected to high oil pressures (>1 0 bars), and therefor needs a proper installation to carry all loads. Today, a majority of all oil filter inserts are threaded into place and this requires a rather high torque and subsequently use of special tools to measure the applied torque. Also, the sealing is located either in a radial way, and the torque is only applied to get a safe non-outthreading of the oil filter, or in an axial way, and therefor need the torque to compress the sealing ring to get a firm, leakfree sealing of the oil filter installation. All of those need either a torque measurement or a tool to overcome the axial compression and angular supervision plus operator skill to decide when the oil filter has reached the corresponding contact surface.

SUMMARY

A first object of the invention is to provide a filter arrangement, which creates conditions for an efficient filter insert exchange.

The object is achieved by a filter arrangement according to claim 1 . Thus, it is achieved by a filter arrangement comprising a filter housing with an access opening for receipt of a removable filter insert and a filter housing counterpart, which is adapted for opening and closing, respectively, the filter insert access opening of the filter housing, wherein the filter housing counterpart and the filter housing comprise means complimentary shaped for fastening of the filter housing counterpart to the housing via a first relative linear movement and a consecutive relative turning movement. According to one example, the filter housing counterpart is formed by a lid moveable relative to a stationary filter housing and for ease of presentation, the invention will be described below for that example. However, the invention is not limited to that example and the filter housing counterpart may instead be formed by a stationary filter head, wherein the filter housing forms the moveable part and similar technical effects and advantages may be achieved. According to the lid example, the object is achieved by a filter arrangement comprising a filter housing with an access opening for receipt of a removable filter insert and a filter housing lid, which is adapted for opening and closing, respectively, the filter insert access opening of the filter housing, wherein the lid and the filter housing comprise means complimentary shaped for fastening of the lid to the housing via a first linear movement of the lid and a consecutive turning movement of the lid. In other words, the lid and the filter housing forms a type of key-lock structure. This design creates conditions for achieving a locking functionality when the lid is turned relative to the filter housing during the consecutive turning movement. According to one example, the fastening means of the lid and housing, respectively, are designed for that the turning movement follows directly on the linear movement. Preferably, the fastening means is adapted for allowing and possibly guiding a linear movement of the filter lid towards the filter housing. Further preferably, the fastening means is adapted for allowing a movement of the filter lid towards the filter housing along a longitudinal axis of the filter housing so that a center axis of the lid coincides with the longitudinal axis of the filter housing.

Thus, this design of filter arrangement differs from conventional designs, where the lid is fastened to the filter housing via a threaded structure, wherein the lid is fastened to the filter housing solely via a rotational movement. More specifically, the invention creates conditions for decreasing cost of ownership and leadtime at the work-shop. For example, the invention creates conditions for removal of use for special tools to produce the turning torque to install the engine oil filter properly, decreased time for service, and decreased cost of ownership and/or decreased cost for service contracts, due to less time spent gathering and putting back tools from cabinets. It also creates conditions for making the service easier, by reducing the forces used by the mechanic, wherein an ergonomical benefit is achieved.

Preferably, the fastening means of the lid and the filter housing are designed for a relative turning movement of less than a complete turn and especially less than half a complete turn and especially less than a quarter of a complete turn, which creates conditions for a quick attachment and removal of the lid from the housing.

According to one embodiment example, the filter housing and the filter housing counterpart are adapted for the first relative linear movement in parallel with a center axis of the filter housing counterpart and the consecutive relative turning movement around the center axis. According to the lid example, the lid is adapted for the first linear movement in parallel with a center axis of the lid and the consecutive turning movement of the lid around the center axis.

According to a further embodiment example, the filter housing defines a longitudinal center axis and wherein the complimentary shaped fastening means of the filter housing counterpart and the housing are arranged for allowing the first relative linear movement when they are positioned so that the center axis of the filter housing counterpart is aligned with the longitudinal center axis of the housing. According to the lid example, the filter housing defines a longitudinal center axis and wherein the complimentary shaped fastening means of the lid and the housing are arranged for allowing the first linear movement of the lid when the lid is positioned so that its center axis is aligned with the longitudinal center axis of the housing.

According to a further embodiment example, a peripheral edge of the filter housing counterpart and a corresponding peripheral part of the filter housing are complimentary designed for allowing the first relative linear movement only when the filter housing counterpart and the filter housing are positioned relative to one another in a predefined circumferential relationship. According to the lid example, a peripheral edge of the lid and a corresponding peripheral part of the filter housing are complimentary designed for allowing the first linear movement of the filter lid only when the lid and housing are positioned relative to one another in a predefined circumferential relationship. Thus, the fastening means is designed for blocking the lid from the linear movement relative to the housing if the lid and housing are positioned in a non-matching circumferential relationship. The embodiment is not limited to only one single predefined circumferential relationship but instead comprises a plurality of predefined relative circumferential relationships. According to a further development of the last mentioned embodiment example, the peripheral edge of one of the filter housing counterpart and the filter housing defines a circular boundary, which is discontinuous, wherein the peripheral part of the other of the filter housing counterpart and the filter housing comprises a circular wall matching the circular boundary and being provided with a radially projecting structure for allowing movement of the external peripheral edge passed the radially projecting structure during the relative linear movement only when the filter housing counterpart and the filter housing are positioned relative to one another in a predefined circumferential relationship.

According to the lid example, the peripheral edge of the lid defines a circular boundary, which is discontinuous, wherein the peripheral part of the housing comprises a circular wall matching the circular boundary of the lid and being provided with a radially projecting structure for allowing movement of the external peripheral edge of the lid passed the radially projecting structure during the linear movement of the lid only when the lid and housing are positioned relative to one another in a predefined circumferential relationship. This specific design creates conditions for achieving a locking functionality when the lid is turned relative to the filter housing during the consecutive turning movement in a space efficient way. Preferably, the peripheral edge of the lid is an external peripheral edge and the radially projecting structure of the housing projects radially inwards.

According to a further development of the last mentioned embodiment example, said one of the filter housing counterpart and the filter housing comprises at least one passage at its peripheral edge between a first side and a second side, wherein the radially projecting structure of the other one of the filter housing counterpart and the filter housing comprises at least one radially projecting element, and wherein the passage and the radially projecting structure are designed for interaction for allowing the first relative linear movement. According to the lid example, the lid comprises at least one passage at its peripheral edge between an upper side of the lid and a lower side of the lid, wherein the radially projecting structure of the filter housing comprises at least one radially projecting element, and wherein the passage and the radially projecting structure are designed for interaction for allowing the first linear movement of the lid. The upper side and lower side of the lid are provided on opposite sides of the lid in the center axis direction.

According to a further example, the passage has the shape of an arc in a cross section at right angles to the center axis direction of the lid. Preferably, the passage extends radially inwards from the circular boundary of the lid. Preferably, the passage has the external shape of a semi-circle.

The radially projecting element and the passage has substantially the same shape and size in a cross section at right angles to the center axis direction of the housing and the lid, respectively, for a tight fit.

According to a further development of the last mentioned embodiment example, the radially projecting element is plate shaped with a main extension substantially perpendicular to a center axis of the filter housing counterpart or a longitudinal axis of the filter housing, respectively. According to the lid example, the radially projecting element is plate shaped with a main extension substantially perpendicular to a longitudinal axis of the housing. In other words, the radially projecting element has a main extension substantially in a radial direction of the housing. According to one example, the radially projecting element is substantially flat and having a continuous thickness. According to one example, the radially projecting element has a continuously decreasing circumferential extension in a radial direction from a first end at the wall to a second, free end. Such a design of the radially projecting element creates conditions for a good feedback to a service technician turning the lid to its operational position in that a continuously increasing surface will come into contact with the lid during the turning movement, wherein the resistance against the turning movement will increase accordingly. According to one example, the radially projecting element has a continuously curved outer edge, or in other words, an arcuate outer edge, wherein the curvature/arc extends in a plane perpendicular to a longitudinal axis of the housing. Such a design is advantageous in that the dimensions of the projection is minimized in relation to its load carrying ability. Further, a proper dimensioning of the radially projecting element creates conditions for a proper strength of the construction during engine operation.

According to a further embodiment example, said one of the filter housing counterpart and the filter housing comprises a peripheral edge portion circumferentially adjacent the passage, which peripheral edge portion is adapted for being positioned behind the radially projecting element in a fastened, operational position, after the relative turning movement for blocking a separation of the filter housing counterpart from the filter housing along its center axis direction or longitudinal direction, respectively. According to the lid example, the lid comprises a peripheral edge portion circumferentially adjacent the passage, which peripheral edge portion is adapted for being positioned behind the radially projecting element in a fastened, operational position of the lid, after the turning movement for blocking a withdrawal of the lid from the housing along its center axis direction. In other words, the peripheral edge portion and the radially projecting element are overlapping in a center axis direction of the lid in the operative, locked position. Thus, a locking functionality is achieved.

According to a further embodiment example, the peripheral edge portion comprises a circumferential stop means for stopping further relative turning movement when the peripheral edge portion has reached its intended position behind the radially projecting element. This design creates conditions for feedback to the service technician attaching the lid during the turning movement that the lid has reached its operative position when the projecting element hits the stop means. The feedback is tactile, but the design of the interacting parts of the lid and housing may be such that there in addition may be a sound when the turning operation is finished. According to a further embodiment example, the peripheral edge portion comprises a seat for the radially projecting element on said first side. According to the lid example, the peripheral edge portion comprises a seat for the radially projecting element on an upper side of the lid. The seat may be slightly recessed thereby blocking any undesired turning movement of the lid relative to the filter housing in an opposite direction relative to the fastening direction. Further preferably, the circumferential stop means is formed by a first side wall portion of the seat at an opposite side of the seat relative to the passage.

This design creates conditions for a firm position during engine operation with the help of the oil pressure created inside the oil circuit. At engine off, the oil pressure is at atmospheric level on both sides of the lid and the oil filter is easy to remove, preferably via a handle or built-in grip, via turning of the lid in the opposite direction to the fastening turning direction followed by an axial withdrawal.

This invention may use a radial sealing element principle, so that no force in axial direction (mount and removal direction) is used for the sealing. During installation, the oil pressure rise inside the filter insert compartment in the housing, which firmly puts the oil filter insert to its seated position, and therefor is hard or not possible to remove whilst the engine is in operation. On the other hand, it is easy to remove the filter insert when the oil pressure is not applied, and the force is just to overcome the friction of the sealing element (such as an o-ring) and the light spring force to seat the oil filter insert.

According to a further example, the seat has the shape of an arc in a cross section at right angles to the center axis direction of the lid. Preferably, the arc extends radially inwards from the circular boundary of the lid. Preferably, the seat has the shape of a semi-circle. Preferably, the seat and the radially projecting element has substantially the same shape and size in a cross section at right angles to the center axis direction of the housing and the lid, respectively, for a tight fit.

According to one example, the passage is circumferentially spaced from the seat so that a centre plane of the passage through a centre axis of the filter forms an angle of at least 20 degrees, preferably at least 30 degrees, especially at least 40 degrees in relation to a centre plane of the seat through the centre axis of the filter. According to one example, the passage is circumferentially spaced from the seat so that a centre plane of the passage through a centre axis of the filter forms an angle of less than 90 degrees, preferably less than 70 degrees, especially less than 50 degrees in relation to a centre plane of the seat through the centre axis of the filter. It creates conditions for an easy mounting/dismounting operation via a single hand grip. Further preferably, the passage is configured for guiding the plate shaped member relative to the projecting element during the linear movement of the lid.

According to a further embodiment example, the seat is defined by a bottom surface facing in a center axis direction of the filter housing counterpart or a longitudinal axis of the filter housing, respectively and a side wall forming a boundary for the bottom surface and extending substantially in parallel with the center axis direction of the filter housing counterpart or a longitudinal axis of the filter housing, respectively. According to the lid example, the seat is defined by a bottom surface facing in a center axis direction of the lid and a side wall forming a boundary for the bottom surface and extending substantially in parallel with the center axis direction of the lid. This design creates conditions for a secure receipt of the radially projecting element.

According to a further embodiment example, said one of the filter housing counterpart and the filter housing comprises a plurality of circumferentially spaced pairs of passage and seat. According to the lid example, the lid comprises a plurality of circumferentially spaced pairs of passage and seat. Further, the housing comprises a number of circumferentially spaced radial projections corresponding to the number of pairs of passage and seat. This design creates conditions for a robust construction due to the fact that the engagement contacts between the lid and the filter housing are provided at a plurality of circumferentially spaced positions. According to one example, the pairs of passage and seat are distributed equally spaced around the circumference of the lid. According to one example, there are four such pairs of passage and seat. Accordingly, the radial projections are distributed equally spaced around the circumference of the housing. According to one example, there are four such radial projections.

According to a further embodiment example, the peripheral edge portion comprises a contact surface on saidfirst side, which contact surface is positioned circumferentially between the passage and the seat for contacting the radially projecting element during the relative turning movement. According to the lid example, the peripheral edge portion comprises a contact surface on an upper side of the lid, which contact surface is positioned circumferentially between the passage and the seat for contacting the radially projecting element during the turning movement. According to a further embodiment example, the contact surface and/or a corresponding contact surface of the radial projection is inclined relative to a circumferential direction for forming an increasing resistance against the relative turning movement during fastening of the filter housing counterpart to the filter housing. According to the lid example, the contact surface of the lid and/or a corresponding contact surface of the radial projection is inclined relative to a circumferential direction for forming an increasing resistance against the turning movement during fastening of the lid to the housing. This design creates conditions for continuous feedback to the service technician attaching the lid during the turning movement that the lid approaches its closed, operational position. Such a corresponding contact surface of the radial projection would be provided on one of its flat sides. The contact surface of the other one of the lid and the radial projection may have an extension that differs from said inclination and preferably have an extension substantially perpendicular to the center axis direction. According to one example, the contact surface of the lid is inclined in a direction from the passage to the seat and the corresponding contact surface of the radial projection extends perpendicular to the center axis direction. Preferably, the contact surface forms a crest at the end of the inclination. Further preferably, in the case the contact surface is provided on the lid, the crest is positioned closer to the seat than the passage. Further preferably, the crest is defined by a side wall of the seat. This design creates further conditions for feedback to the service technician in that the resistance against the turning movement will decrease when the radially projecting element passes the crest towards the operative position. More specifically, the resistance against the turning movement will increase while the radially projecting element rides along the slope and suddenly decrease when the radially projecting element passes the crest towards the operative position. According to one example, the inclined contact surface has a constant inclination. According to one example, the contact surface has an inclination angle of less than 1 0 degrees and more than 4 degrees. The contact surface may form a ramp in a circumferential direction. Further, the interacting fastening means of the lid and housing are preferably designed for an easy removal of the lid from the housing, wherein the design of the contact surface and/or crest is adapted for easily being override during turning of the lid in the opposite direction to the fastening direction. According to a further embodiment example, the other one of the filter housing counterpart and the filter housing comprises a circumferentially extending contact surface facing in the center axis direction of the filter housing counterpart or the longitudinal direction of the filter housing, respectively, and positioned at a distance from the radially projecting element in said direction and wherein the peripheral edge portion has an extension between the first side and the second side matching the distance between the radially projecting element and the circumferentially extending contact surface for being wedged between the radially projecting element and the circumferentially extending contact surface during the relative turning movement and thereby creating a resistance against the turning movement. According to the lid example, the housing comprises a circumferentially extending contact surface facing in the longitudinal direction of the housing and positioned at a distance from the radially projecting element in the longitudinal direction and wherein the peripheral edge portion of the lid has an extension between the upper side and the lower side of the lid matching the distance between the radially projecting element and the circumferentially extending contact surface for being wedged between the radially projecting element and the circumferentially extending contact surface during the turning movement of the lid and thereby creating a resistance against the turning movement. This design creates conditions for continuous feedback to the service technician attaching the lid during the turning movement that the lid approaches its closed, operational position. More specifically, the resistance against the turning movement will increase during engagement of the wedging area and decrease when the radially projecting element passes the wedging area towards the operative position. This design creates conditions for a good feedback to the service technician of the status of the fastening of the lid to the filter housing, especially in the case the lid and filter housing are designed for fastening of the lid solely via hand force.

According to a further embodiment example, the other one of the filter housing counterpart and the filter housing comprises a circumferentially extending contact surface facing in the center axis direction of the filter housing counterpart or the longitudinal direction of the filter housing, respectively, forming a stop for the relative linear movement. According to the lid example, the housing comprises a circumferentially extending contact surface facing in the longitudinal direction of the housing forming a stop for the linear movement of the lid. The circumferentially extending contact surface is provided closer to a bottom end of the housing than the radially projecting member and overlap with the radially projecting element in the longitudinal direction of the housing. According to a further embodiment example, said one of the filter housing counterpart and the filter housing comprises a plate shaped member. According to the lid example, the lid comprises a plate shaped member. According to one example, the plate shaped member defines the peripheral external edge. This design creates conditions for a space-efficient and/or cost-efficient lid.

According to a further embodiment example, said one of the filter housing counterpart and the filter housing comprises a handle. According to the lid example, the lid comprises a handle. According to one alternative, the handle is arranged for operation from an upper side of the plate shaped member. The handle may be used to manually provide a turning torque to fasten the lid to the filter housing.

According to a further embodiment example, the lid comprises means for engagement with a complimentary shaped engagement means of the filter insert. By arranging the lid and the filter insert with complimentary shaped engagement means, a used filter insert will be withdrawn from the filter housing together with the lid when the lid is detached from the filter housing. This may be achieved in that the lid has a centrally positioned engagement structure projecting in a center axis direction of the lid and the filter insert has a complimentary shaped engagement structure projecting in an axial direction of the filter insert. It creates conditions for a less messy filter insert exchange operation since the service operator may only contact the lid during withdrawal of the filter insert from the filter housing, especially if the lid engagement means is adapted for a connection between the lid and the filter insert guiding means allowing the filter insert and the lid to be interconnected for being moved in unison in relation to the filter housing. Further, the engagement means creates conditions for an environmentally friendly solution in that the lid may be detached from a used filter insert and reused. According to a further embodiment example, the engagement means projects from a lower side of the plate shaped member. According to a further embodiment example, the filter arrangement comprises a filter insert for being positioned in a compartment in the housing and wherein the filter insert comprises a filter material body. The filter material body preferably has a cylindrical shape. The term "cylindrical shape" defines a volume enclosed by two planes perpendicular to an axis extending in an axial direction of the filter insert. The cross section of the cylinder at right angles to the axis is preferably circular forming a right circular cylinder. The filter material body may be hollow- cylindrical and formed by a pleated structure. However, the filter material body may be non-cylindrical, for example the volume may not be defined by two planes perpendicular to an axis. The axially limiting portions of the filter material body may be planes, but at least one of them may be non-perpendicular in relation to said axis. Further, at least one of the axially limiting portions of the filter material body may have a shape deviating from a straight plane, such as curved. The filter material body may be formed by a pleated structure, such as cellulose material.

Further, the filter insert preferably comprises a filter material body support structure on at least one of the first end and the second end, wherein the filter material body support structure has a main extension in a direction transverse to an axial direction of the filter insert. The filter material body support structure is preferably configured to give a rigid support to the filter insert. The filter material body support structure is preferably configured to be provided with sealing means for sealing the filter insert to the filter housing and the lid, respectively. Preferably, the filter material body support structure has a plate shaped structure. Preferably, the filter material body support structure is attached to one end of the filter material body. The filter material body support structure may be formed by a separate unit, such as a plastic disc attached to the filter material body. Alternatively, the filter material body support structure may be formed by attaching a glue or other substance to an end of the filter material body. The substance attached may dissolve an end portion of the filter material body, which is then solidified, so that the filter material body support structure is partly made up of an end portion of the filter material body. This may for example be the case where the filter material body is formed by a pleated paper.

According to a further embodiment example, the filter insert is releasably connected to the lid via engagement means. This design creates conditions for an environmentally friendly solution in that the lid may be detached from a used filter insert and reused. According to an alternative, the lid is rigidly attached to the filter insert forming a one-piece unit.

According to a further embodiment example, the filter insert is adapted for filtering a fluid, such as oil, fuel or air, for an internal combustion engine.

Further, the invention is directed towards an internal combustion engine system comprising an internal combustion engine and a filter arrangement according to any one of the embodiment examples described above operatively connected to the internal combustion engine for filtering a fluid for the internal combustion engine.

Further advantages and advantageous features of the invention are disclosed in the following description and in the dependent claims. BRIEF DESCRIPTION OF THE DRAWINGS

With reference to the appended drawings, below follows a more detailed description of embodiments of the invention cited as examples. In the drawings:

Fig. 1 discloses a vehicle in the form of a truck in a side view,

Fig. 2 discloses an internal combustion engine of the truck in a perspective view with a filter arrangement attached,

Fig. 3 discloses the filter arrangement of figure 2 in a partly assembled state,

Fig. 4 is a perspective view from the top of a filter insert according to a first embodiment example,

Fig. 5 is a perspective view from below of the filter insert according to the first embodiment example, Fig. 6 is an exploded view of the filter insert of figure 4-5, Fig. 7 is a perspective view from the top of a lid according to a first embodiment example,

Fig. 8 is a perspective view from below of the lid according to the first embodiment example,

Fig.9 is a partially cut perspective view from the top of the lid according to the first embodiment example attached to the filter insert according to the first embodiment example,

Fig. 10 is a partially cut perspective view from the top of a filter housing according to a first embodiment example,

Fig. 1 1 is an exploded view of a filter arrangement according to a first embodiment example comprising the filter insert, lid and filter housing according to figures 1 -10,

Fig. 12 is a partly cut cross sectional view of the filter arrangement according to figure 1 1 in an operational state, and Fig. 13 is a perspective view from the top of a filter insert according to a second embodiment example.

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS OF THE INVENTION

Figure 1 discloses a vehicle in the form of a truck 1 in a partly cut side view. Further, an internal combustion engine, ICE, in the form of a diesel engine 2 is indicated.

Figure 2 shows the ICE 2 provided with a filter arrangement 3 according to a first embodiment of the invention. The filter arrangement 3 is adapted for filtering a fluid for the ICE. More specifically, there are three filter arrangements 3 arranged in parallel with each other. Other numbers of filter arrangements may of course also be feasible depending on space constraints and other reasons, such a single filter arrangement or two filter arrangements. The filter arrangement 3 comprises a filter housing 105, which is attached to the ICE. The filter arrangement 3 is in an upright, standing position, slightly inclined outwards from its attachment at the bottom relative to a side of the ICE. A lower section of the filter arrangement comprises inlets and outlets. The filter housing 105 is in the form of a cup-shaped part, which is rigidly attached to the ICE at the lower section. The filter housing 105 defines a longitudinal center axis 107 along which a filter insert (not shown) can be inserted into the filter housing and removed from the filter housing via an access opening 109, see figure 3. The filter arrangement 3 further comprises a lid 120 for closing the filter housing.

Figure 3 discloses the filter arrangement 3 of figure 2 in a partly assembled state. A filter insert 100 according to a first embodiment example is attached to the lid 120 for being inserted into the filter housing 105 via the access opening 109 via a first linear movement in parallel with the longitudinal axis 107 followed by a turning movement around the longitudinal axis 107.

Figures 4 and 5 show the filter insert 100 from figure 3 for being removably arranged in the filter housing 105. Figure 6 is an exploded view of the filter insert of figure 4-5. The filter insert 100 defines a first end 104 and a second end 106 opposite the first end.

The filter insert 100 comprises a filter material body 102. The filter material body 102 has a cylindrical shape. The cross section of the cylinder at right angles to the axis is circular forming a right circular cylinder. More specifically, the filter material body 102 is hollow- cylindrical defining a central opening. Further, the filter material body 102 is formed by a pleated paper structure extending between the central opening and a radially outer circumference of the filter insert.

The filter insert 100 comprises a filter material body support structure 108,1 10 at both the first end 104 and the second end 106, wherein the filter material body support structure 108,1 10 has a main extension in a direction transverse to an axial direction 103 of the filter insert. The filter material body support structure has a plate shaped structure extending in a plane perpendicular to the axial direction 103 of the filter insert. The filter material body support structures 108,1 10 will in the following be referred to as an upper and lower panel 108,1 10. Thus, the filter material body 102 is delimited on the top by the upper panel 1 10 and on the bottom by the lower panel 108. The panels 108,1 10 may be formed by separate parts attached to the filter material body 102. The filter material body 102 is then bonded to the upper panel 108 and lower panel 1 10 at the edges of the filter paper in the axial direction of the filter insert. Alternatively, the panels 108,1 10 are formed by a glue or other fastening fluid attached to the edges of the filter material body 102 in the axial direction of the filter insert and then solidifed.

The filter insert 100 further comprises means 1 16 for engagement with the lid 120. It creates conditions for a less messy filter insert exchange operation since the service operator may only contact the lid during withdrawal of the filter insert from the filter housing, especially if the lid engagement means is adapted for a connection between the lid and the filter insert guiding means allowing the filter insert and the lid to be interconnected for being moved in unison in relation to the filter housing. The lid engagement means 1 16 is formed by a snap connection means 1 16 projecting axially from the upper panel 1 10. Thus, the lid engagement means 1 16 is rigidly attached to the upper panel 1 10. The snap connection means 1 16 comprises a plurality of circumferentially spaced fingers adapted for a radial flex. More specifically, each finger has a first portion 1 16' attached to the upper panel 1 10 and extending in parallel with the axial direction 103. Further, each finger has a second portion 1 16" with a radial extension outwards from a free end of the first portion 1 16'. During connection to the lid, the circumferentially spaced fingers are configured to bend slightly radially inwards for passing an annular section of the lid and then flex back behind the annular section for locking the filter insert 100 to the lid 1 20.

The filter insert 100 further comprises sealing means 122,124 for sealingly engage an inner surface of the filter housing 105 and the lid 120, respectively, in order to separate a raw side from a clean side of the filtering arrangement. A first sealing means 122 in the form of a ring is provided on an external side of the upper panel 1 10 for a sealing engagement with the lid 120. A second sealing means 124 in the form of a ring is provided on an external side of the lower panel 108 for a sealing engagement with a bottom surface of the filter housing 105.

Figures 7 and 8 are perspective views from the top and bottom, respectively, of the lid 120 according to a first embodiment example. The lid 120 comprises means 126,127,128 for fastening of the lid 120 to the housing 105 via a first linear movement of the lid and a consecutive turning movement of the lid. More specifically, the lid 120 has an external peripheral edge 126, which defines a generally circular boundary for allowing a turning movement of the lid relative to the housing while contacting an internal peripheral circular surface of the housing. The generally circular boundary is discontinuous, or interrupted, in the circumferential direction. The interruptions are formed by circumferentially spaced passages 128.

The external peripheral edge 126 forms part of a key-lock structure for fitting with a complimentary shaped part of the filter housing 105 during a movement of the filter lid towards the filter housing. The key-lock structure is adapted for a linear movement of the filter lid 120 towards the filter housing 105. More specifically, the key-lock structure is adapted for allowing a movement of the filter lid 120 towards the filter housing 105 along the longitudinal axis 107 of the filter housing so that the center axis 1 1 1 of the lid coincides with the longitudinal axis 107 of the filter housing in a certain relative circumferential position. The lid 120 comprises a plate shaped member 123 defining the external peripheral edge 126. The plate shaped member 123 of the lid 120 is discontinuous at its peripheral edge 126 in a circumferential direction of the lid for allowing a relative axial movement of the plate shaped member 123 passed a radially inwards projecting element 147 of the filter housing 105, see figure 10. More specifically, the plate shaped member 123 forms a passage 128 at its peripheral edge 126 for the radially inwards projecting element 147, see figure 10. An extension direction of the passage 128 is in parallel with the center axis 1 1 1 of the lid 120. The plate shaped member 123 comprises a seat 127 at a second side 1 12 of the plate shaped member for receipt of the radially inwards projecting element 147 of the corresponding key-lock structure of the filter housing. The seat 127 is defined by a bottom surface 150 facing in a center axis 1 1 1 direction of the lid 120 and a side wall 152 forming a boundary for the bottom surface and extending substantially in parallel with the center axis 1 1 1 direction of the lid. The seat has the shape of an arc in a cross section at right angles to the center axis direction of the lid.

The passage 128 is circumferentially spaced from the seat 127. The passage 128 is configured for guiding the plate shaped member 123 relative to the projecting element 147 during the linear movement of the plate shaped member passed the projecting element. The passage 128 has the shape of an arc in a cross section at right angles to the center axis direction of the lid. The passage 128 has a shape complimentary to the seat 127 and especially the same cross section with regard to shape and size. The plate shaped member 123 comprises a plurality of circumferentially spaced pairs of seat and passage. The plate shaped member 123 comprises a first portion 136 for being positioned behind the projecting element 147 in a connected, operational position of the lid, after the turning movement for blocking a withdrawal of the plate shaped member along a center axis of the lid. Further, the plate shaped member 123 comprises a stop means 138 for stopping further relative turning movement of the plate shaped member when the first portion has reached its intended position behind the radially projecting element 147. A bottom surface of the seat is recessed and wherein the stop means is formed by a first side wall portion of the seat at an opposite side of the seat relative to the passage. The plate shaped member 123 forms a contact surface 137 for the projecting member 147 between the passage 128 and the seat 127. The contact surface 137 faces in the center axis direction of the lid. The projecting member guiding surface 137 forms a crest 139. Further preferably, the crest 139 is positioned closer to the seat 127 than the passage 128. Further preferably, the crest 139 is defined by a side wall of the seat 127. The contact surface 137 between the passage 128 and the crest 139 has an inclination angle of less than 10 degrees and preferably more than 4 degrees with regard to a plane perpendicular to the center axis of the lid.

A portion 130 of the plate shaped member 123 between the axial passage 128 and the seat 127 is arranged to be wedged between the projecting element 147 and an axially opposite, circumferentially continuous surface 142 of the filter housing, see figure 10, during the turning movement of the lid 120 thereby creating a resistance to the turning movement. The lid 120 comprises a handle 134 at the second side 1 12 of the lid for manual operation of the lid by a service technician.

The lid 120 comprises a means 146 for engaging the filter insert 100 so that the lid and the filter insert can be moved in unison relative to the filter housing, especially during withdrawal of a used filter insert from the filter housing. Said filter insert engaging means 146 is formed by a central tubular structure projecting from the first side 125 of the lid for engaging the snap means 1 16 of the filter insert. The tubular structure has a circumferentially extending groove in a radially inner wall for receipt of the second portion 1 16" of the snap means 1 16 of the filter insert 100 enabling a used filter insert 100 to be withdrawn from the filter housing 105 in unison with the lid 120. The lid 120 further comprises an annular part 129 in the form of a collar projecting from the first, lower side of the plate shaped portion 123, which part 129 has a surface adapted for sealing engagement with a corresponding surface of the filter housing. Further, the 5 sealing part 129 forms a one-piece unit with the plate shaped portion 123.

Figure 9 is a partially cut perspective view from the top of the lid according to the first embodiment example attached to the filter insert according to the first embodiment example.

10

Figure 10 shows the filter housing 105 according to a first embodiment example. The filter housing 105 has an access opening 109 for receipt of the filter insert 100 and wherein the filter housing lid 120 is arranged for opening and closing, respectively, the filter insert access opening 109. The filter housing 105 comprises a compartment 154 for the filter

15 insert 100 defined by a cylindrical wall 152. The filter housing 105 comprise means 142,147 for fastening of the lid to the housing via a first linear movement of the lid and a consecutive turning movement of the lid. The fastening means 142,147 forms part of the key-lock structure for fitting with the complimentary shaped plate shaped member 123 of the lid during a movement of the lid relative to the filter housing. A circular wall 1 13 of the

20 housing 105 matching the circular boundary of the lid 120 is positioned radially spaced from the cylindrical wall 152. The radial distance between the circular wall 1 13 and the cylindrical wall 152 is at least partly bridged by a circumferentially extending wall having an upper surface 142 facing in the longitudinal direction of the filter housing.

25 The filter housing 105 comprises a circumferential groove 148 at the access opening 150 for receipt of a radially outer part of the plate shaped member 123 of the lid during the turning movement of the lid relative to the filter housing. The groove 148 is defined in the longitudinal direction 107 of the filter housing 105 on one side by a surface of the radially extending projection 147 and on the other side by an axial stop formed by said surface

30 142.

The radially extending projection 147 projects radially inwards from the circular wall 1 13. The radially extending projection 147 is plate-shaped and flat and extends in a plane perpendicular to the longitudinal direction 107 of the filter housing 105. Further, the 35 radially extending projection 147 is arc-shaped, wherein the arc defines a radially outer surface of the plate-shaped portion 147. Further, the radially extending projection 147 has the external shape of a semi-circle. The shape and size of the radially extending projection 147 is matched to the seat and the passage and preferably the same or somewhat smaller in size for a tight fit. According to a further embodiment example, the seat and the passage has substantially the same shape in a cross section at right angles to an axial direction of the filter.

The cylindrical inner wall 152 has a circular cross section. The diameter of the circular cylindrical wall 152 is matched to the diameter of the filter material body 102 establishing a gap between them.

The filter housing 105 has a central upstanding, tubular portion 131 for receipt in the opening of the filter insert at a lower portion thereof extending from a bottom of the filter housing chamber. The tubular portion 131 is arranged to guide the filter insert to its correct operational position. Further, the sealing means is realized between the tubular portion 131 and the sealing 124 of the filter insert. The tubular portion 131 forms a fluid permeable central post. The central post 131 is grid-shaped.

The filter housing 105 comprises an inlet 132 for receipt of a raw fluid to be filtered, which empties into a raw side of the filter housing, and an outlet or return 134, which starts at a clean side of the filter housing, for filtered clean fluid. The inlet 132 and outlet 134 are provided in a lower region 136 of the filter housing 105. The inlet 132 and outlet 134 are in communication with different sides of the filter material body 102. More specifically, the outlet 134 is provided in a bottom wall 138 of the filter housing and positioned radially centrally and adapted to match the position of the central opening in the tubular portion 131 so that it is in fluid communication with an interior side of the tubular portion 131 . Further, the inlet 132 is positioned radially eccentric in the bottom wall 138 of the filter housing for distributing the fluid to a radially external side of the filter material body 102. The direction of the fluid inside the filter arrangement is disclosed in figure 12. By flowing through the filter material body 102, the liquid flows to the clean side of the filter housing (the radially interior space). The filtered liquid flows off through the outlet (return) 134. Dirt particles are retained in the filter material body 102.

Figure 1 1 is an exploded view of the filter arrangement according to the first embodiment example comprising the filter insert 100, lid 120 and filter housing 105. Figure 13 shows a second embodiment example of a filter insert 200. The lid for closing the housing 105 according to the key-lock function described above is here integrally formed with the filter insert 200. More specifically, the lid forms an integral part of the upper end cap. Thus, during filter insert exchange, the used one-piece unit of filter insert and lid is removed from the housing and a new one-piece unit of filter insert and lid is installed.

It is to be understood that the present invention is not limited to the embodiments described above and illustrated in the drawings; rather, the skilled person will recognize that many changes and modifications may be made within the scope of the appended claims.

According to one alternative, the filter arrangement may have a position relative to the ICE, which differs from an upright, standing position. For example, the filter arrangement may be positioned so that its longitudinal axis is substantially horizontal or even in a position, where the access end faces vertically downwards or in any inclined position between a horizontal and vertical position.

According to one alternative, the filter insert may comprise a central tubular structure positioned inside of the filter material body and in contact with an inner periphery of the filter material body for supporting the filter material body and reduce risk of collapsing of the filter material body. In the case the filter insert has a fluid permeable central tubular structure, the post 131 and the structure should be matched in design and/or rotational position for aligning the through holes allowing fluid through-flow.

According to one alternative, the radially projecting element may have a shape different from a continuous arcuate outer edge extending in a plane perpendicular to a longitudinal axis of the housing. For example, the radially projecting element may have a polygonal shape, such as a rectangular shape or octagonal shape. Further, the shape of the radially projecting element may be a combination of straight and arcuate edge sections, such as opposite straight side edge sections and a curved intermediate edge section connecting the straight side edge sections.

According to one alternative, the lid may have a shape different from flat with parallel straight upper and lower surfaces. For example, one or both of the upper and lower surfaces may belly out. Further, the lid may have a larger thickness centrally than at the peripheral edge.

According to one alternative to that the inlet and outlet are provided in a lower region of the filter housing, the inlet and/or outlet may be arranged at any position along the filter housing in its longitudinal direction. For example, the inlet and/or outlet may be arranged through the cylindrical side wall of the filter housing.

According to one alternative to that the filter housing is stationary and the lid is moveably arranged relative to the filter housing, the filter housing forms a part moveable relative to a stationary filter head comprising the inlet and outlet for the fluid. For example, the filter arrangement may be designed so that filter housing has a closed lower end and is fastened at its open upper end to the filter head, wherein the filter housing will be in a hanging state. Preferably, a handle may be arranged on an external side of the closed lower end of the filter housing and the key-lock structure may be arranged at the peripheral edge of the open upper end of the filter housing.

According to a further alternative, the lid may be designed to encompass at least a part of the filter insert. Thus, the lid may be provided with an annular wall with an extension in its center axis direction. In a similar manner, the filter housing may be designed to encompass only a part of the filter insert, ie not entirely, wherein the counterpart (lid or filter head) is designed to encompass the rest of the filter insert. The key-lock structure may then be provided at the interface between the filter housing and the counterpart.