The present disclosure relates to a vehicle wheel assembly and in particular, but not exclusively, to a vehicle wheel assembly for delivering compressed air from a vehicle axle to a tire. Aspects of the present invention relate to a control valve assembly, an annular cage, a method of manufacturing, a housing, a Central Tire Inflation System (CTIS) and a vehicle.
The present invention was conceived in the context of central tire inflation systems (CTIS). CTIS were originally developed for military applications, in particular off-road military wheeled trucks and trailers. However, CTIS are nowadays incorporated into non-military vehicles such as specialist construction, agricultural and commercial vehicles.
CTIS comprise one or more compressed air sources located on-board the vehicle in fluid communication with one or more tires. Tire pressure can therefore be adjusted by the CTIS. Typically, CTIS provide for delivery of compressed air to a tire through a hose connected to the wheel and in some cases, this is integrated into a vehicle axle. Accordingly, there are vehicle wheels and vehicle wheel assemblies designed to receive incoming flow of compressed air from the axle, and to deliver it to the tire.
U.S. Pat. No. 6,425,427 B1 discloses an on-axle tire inflation system.
US 2005/0236083 A1 discloses a vehicle wheel assembly comprising a rim secured to a wheel hub and a tire secured to the rim, with a hollow stud having an air conduit. The hollow stud extends through a rim opening and has a first end secured to the hub. A lug nut is secured to the hollow stud at a second end. The first end is operably connected to a source of compressed air through the air conduit. A central tire inflation valve is secured to the rim. The rim includes a first internal conduit communicating with the air conduit and the valve, and a second internal conduit communicating with the valve and the interior of the tire.
Drawbacks of the known systems include their adverse effect on wheel styling (which is not typically a concern with trucks but may not be aesthetically acceptable for passenger vehicles), their bulkiness and heaviness.
It is an object of the present invention to further improve on central tire inflation systems.
Aspects and embodiments of the invention provide a control valve assembly, an annular cage, a method of manufacturing, a housing, a Central Tire Inflation System (CTIS)) and a vehicle.
According to one aspect of the present invention there is provided a control valve assembly for use with a vehicle wheel assembly, the control valve assembly comprising;
an inlet for receiving compressed air from a supply line;
an outlet for supplying compressed air to a transfer line;
a control valve for selectively placing the inlet in fluid communication with the outlet;
wherein the control valve assembly is configured to be removably disposed in a wheel hub; and
an annular cage mounted around the outlet, the annular cage supporting a transfer line filter for filtering air moving between the control valve and the transfer line, wherein the cage comprises a base ring and a secondary ring, the transfer line filter extending intermediate the base and secondary rings, wherein the base and secondary rings each comprise a radial foot arranged to space the transfer line filter from the control valve assembly to provide an annular cavity therebetween.
In the event that a part of the filter proximal to the outlet becomes blocked, air will be able to flow around the cavity to other parts of the filter so air flow through the control valve assembly is unaffected by the blockage.
In an embodiment, the cage comprises a plurality of axial spokes, and wherein the transfer line filter comprises a plurality of individual filter elements, wherein adjacent spokes are arranged to support a filter element therebetween. The spokes provide structural rigidity to the cage and the filter.
In an embodiment, the control valve assembly comprises a housing having an annular wall defining a chamber for housing a control valve, the outlet comprising a plurality of through-holes passing through the annular wall.
A plurality of through-holes, as opposed to a single through-hole, provides a degree of redundancy in case of a blockage in one of the through-holes.
In an embodiment, the through-holes are arranged to extend radially around a central axis of the control valve assembly.
In an embodiment, the through-holes are equiangularly spaced apart. An even through flow of air can thus be promoted through the control valve.
According to a further aspect of the present invention there is provided a control valve assembly for a vehicle wheel assembly, the control valve assembly comprising;
The hydrophobic material reduces the likelihood of any condensation from within the tire from flowing back into the supply line via the control valve assembly.
In an embodiment, the control valve assembly comprises a mounting formation and wherein the filter comprises a supply line filter for filtering air moving between the supply line and the control valve. Alternatively or in addition the control valve assembly may comprise an annular cage and the filter may comprise the transfer line filter supported by the annular cage. The annular cage may be mounted around the outlet, the annular cage supporting a transfer line filter for filtering air moving between the control valve and the transfer line, wherein the cage comprises a base ring and a secondary ring, the transfer line filter extending intermediate the base and secondary rings, wherein the base and secondary rings each comprise a radial foot arranged to space the transfer line filter from the control valve assembly to provide an annular cavity therebetween.
According to a further aspect of the present invention there is provided a method of manufacturing at least part of a housing for housing a control valve of a control valve assembly in a Central Tire Inflation System (CTIS) of a vehicle wheel assembly, the housing comprising a circumferential seal surface for receiving at least one O-ring thereon, an outwardly extending circumferential flange for axially constraining said at least one O-ring, the one or more O-ring arranged to seal hermetically the control valve assembly from a wheel hub within which the control valve assembly is removably mounted, the method comprising;
A circumferential flash-line, as opposed to an axially extending flash-line reduces wear on an O-ring and also prevents leakage between the wall and the O-rings.
In an embodiment, the method comprises arranging the mold tool and opposing mold tool to locate the flash-line on the flange. In this way, the flash-line completely avoids the O-ring, in-use.
In an embodiment, at least part of the housing is manufactured in modular form, comprising;
In an embodiment, first and second modules are attached by welding.
In an embodiment, welding comprises ultrasonic welding.
In an alternative or additional embodiment, molding the second section comprises;
Fabricating part of the housing in this way provides greater flexibility in terms of the outer profile of the housing in places where there are to be no O-rings and thus an axial flash-line is not problematic.
According to a further aspect of the present invention there is provided a housing for a control valve of a control valve assembly made using the aforementioned method.
According to a further aspect of the present invention there is provided a Central Tire Inflation System (CTIS) comprising a vehicle wheel assembly, the vehicle wheel assembly comprising a wheel hub and a control valve assembly removably mounted therein, wherein the control valve assembly is the aforementioned control valve assembly.
According to a further aspect of the present invention there is provided a vehicle comprising the aforementioned CTIS.
Within the scope of this application it is expressly intended that the various aspects, embodiments, examples and alternatives set out in the preceding paragraphs, in the claims and/or in the following description and drawings, and in particular the individual features thereof, may be taken independently or in any combination. That is, all embodiments and/or features of any embodiment can be combined in any way and/or combination, unless such features are incompatible. The applicant reserves the right to change any originally filed claim or file any new claim accordingly, including the right to amend any originally filed claim to depend from and/or incorporate any feature of any other claim although not originally claimed in that manner.
One or more embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:
A vehicle wheel assembly 1 in accordance with an embodiment of the present invention for application in a motor vehicle V will now be described with reference to the accompanying Figures. The vehicle wheel assembly 1 forms part of a central tire inflation system (CTIS) for controlling the pressure of a tire 3. The vehicle wheel assembly 1 can be implemented in a range of motor vehicles, including cars, off-road vehicles, sports utility vehicles (SUVs), trucks, buses and so on.
The vehicle wheel assembly 1 comprises a wheel 5 and a control valve assembly 7. The wheel 5 comprises a wheel hub 9, a wheel rim 11 and a plurality of spokes 17A-F (two of the spokes 17E and 17F have not been shown for clarity) which connect the wheel rim 11 to the wheel hub 9. The tire 3 locates on the wheel rim 11 in conventional manner. The control valve assembly 7 is removably disposed within the wheel hub 9 and is in fluid communication with a compressed air supply in the form of a compressor C and/or a reservoir (not shown) provided on the vehicle. In the present embodiment, fluid communication with the compressed air supply is established through a supply line 13 extending along a central axis of a drive shaft 15 (both shown schematically in
In the example shown in the figures, the wheel 5 is made of a cast metallic alloy, such as aluminium or magnesium, and is of a type generally used in automotive vehicles. The wheel 5 has six spokes 17A-F, but can have less than or more than six spokes 17. A first spoke 17A is hollow and comprises a transfer line 19 extending radially outwardly from the wheel hub 9 to the rim 11. A first end of the transfer line 19 communicates with a radially outer opening 21 disposed on the rim 11 and through which the tire can be inflated/deflated; and a second end of the transfer line 19 communicates with a radially inner opening 23 disposed on the wheel hub 9. The radially outer opening 21 opens into an interior of the tire 3 such that a fluid pathway is established between the supply line 13 and the interior of the tire 3. The transfer line 19 could be machined in the first spoke 17A, but in the present embodiment it is formed during the casting process. The other spokes 17B-F can also be hollow to help balance the wheel assembly 1.
The control valve assembly 7 comprises a control valve 25 mounted in a housing 27.
A wheel valve 39 is provided for sealingly closing the transfer line 19 in the first spoke 17A when the control valve assembly 7 is removed from the wheel hub 9. In the present embodiment, the wheel valve 39 is disposed at the radially inner opening 23 of the transfer line 19, but it could be disposed along the length of the transfer line 19 or at the radially outer opening 21. The wheel valve 39 comprises a fixed sleeve 41, a movable valve member 43, and a resilient biasing means in the form of a coil spring 45. The valve member 43 has a valve head 47 for cooperating with a valve seat 49 formed in the sleeve 41. The valve member 43 is movable between a closed position (shown in
A first O-ring 51 is provided around the valve head 47 for forming a seal between the valve seat 49 and the valve member 43. When the valve member 43 is in its closed position, the wheel valve 39 is closed and the supply of air to the tire 3 and/or the exhausting of air from the tire 3 through the transfer line 19 formed in the first spoke 17A is inhibited. The spring 45 biases the valve member 43 towards its closed position, as illustrated by a first arrow A shown in
Displacement means in the form of a pin 53 is coupled to the valve head 47 to cooperate with the control valve assembly 7 and displace the valve member 43 to its open position. Specifically, when the control valve assembly 7 is mounted in the wheel hub 9, the closure member 31 engages the pin 53 and displaces the valve member 43 to its open position, as shown in
In the present embodiment, the control valve 25 is a pneumatic latching valve which can be selectively opened and closed in response to the application of control pressures. The control valve 25 has an axial inlet port 55 and a radial outlet port 57. A frusto-conical nozzle 59 is mounted to the inlet port 55 (shown in
The control valve 25 is disposed centrally within the valve chamber 33 formed by the base member 29 and the closure member 31. A first annular chamber 61 is formed within the housing 27, extending circumferentially around the control valve 25 to maintain fluid communication with the outlet port 57 irrespective of the angular orientation of the control valve 25. A second annular chamber 63 is formed between the housing 27 and the wheel hub 9 to ensure that fluid communication with the transfer line 19 in the first spoke 17A is maintained irrespective of the angular orientation of the control valve assembly 7. The first and second annular chambers 61, 63 are arranged concentrically about the rotational axis a-a in the present embodiment. An offset bore 65 is formed in the base member 29 to establish fluid communication between the first and second annular chambers 61, 63. The wheel valve 39 opens into the second annular chamber 63, thereby establishing fluid communication between the supply line 13 and the first spoke 17A when the wheel valve 39 and the control valve 25 are open.
The nozzle 59 is formed from a resilient material, such as rubber, and has a frusto-conical outer surface 66 for sealingly engaging a cooperating inner surface 67 formed in the drive shaft 15. Said drive shaft inner surface could be cylindrical and could comprises a thread for engagement with a corresponding thread provided on a corresponding cylindrical outer surface of a stub axle fluid connector. This stub axle fluid connector can be substantially in the form of a bolt having a head configured to engage with the frusto-conical outer surface 66 of the nozzle 59. Said fluid connector can therefore threadedly engage with the cylindrical drive shaft inner surface at one end. At the other end, the fluid connector can receive the frusto-conical outer surface 66 of the nozzle 59 by means of a frusto-conical passageway formed in the head.
A pair of retaining clips 69, 71 is mounted to the closure member 31 for releasably fixing the control valve assembly 7 within the wheel hub 9. A spring 73 is provided to bias the clips 69, 71 radially outwardly to engage a first annular recess 75 formed in the cylindrical sidewall 35 of the hub 9. A second O-ring 77 is provided for forming a seal between the closure member 31 and the wheel hub 9. The second O-ring 77 locates in a second annular recess 78 formed in the cylindrical sidewall 35.
The control valve assembly 7 is removably mounted in the hub cavity 37 from an inside of the vehicle wheel assembly 1, as illustrated by a second arrow B in
A circular locating member 81 disposed at the end of the base member 29 locates in a circular aperture 83 formed in the hub 9. The locating member 81 extends through the hub 9 to the outer side of the wheel assembly 1. An annular flange 85, formed around the circular locating member 81, cooperates with an axial retaining means in the form an annular projection 87 formed in the wheel hub 9. A third O-ring 89 is mounted to the base member 29 to form a seal between the annular flange 85 and the annular projection 87.
The control valve assembly 7 is removably mounted within the hub cavity 37. When the control valve assembly 7 is located in the wheel hub 9, the locating member 81 is disposed within the circular aperture 83. When installed at a prescribed axial location within the wheel hub 9, the closure member 31 engages the pin 53 of the wheel valve 39, thereby displacing the valve member 43 to its open position. The annular flange 85 and third O-ring 89 abut the annular projection 87 and the closure member 31 and the second O-ring 77 abut the radial surface 79 formed in the wheel hub 9. The second and third O-rings 77, 89 form seals between the wheel hub 9 and the closure member 31 and the base member 29 respectively. The first and second annular chambers 61, 63 are thereby sealed when the valve control assembly 7 is located in the wheel hub 9. The clips 69, 71 locate in the first annular recess 75 formed in the wheel hub 9 to retain the control valve assembly 7 in position. The clips 69, 71 can be displaced radially inwardly to release the control valve assembly 7, as shown by arrows D in
The fluid pathway through the control valve assembly 7 and the wheel 5 during tire inflation will now be described with reference to
The second annular chamber 63 is in fluid communication with the wheel valve 39. When the control valve assembly 7 is mounted in the wheel hub 9, the closure member engages the pin 53 and displaces the valve member 43 to its open position. The wheel valve 39 is thereby opened to establish fluid communication between the second annular chamber 63 and the cavity 4 of the tire 3 via the transfer line 19. The control valve 25 is operable to control the supply of compressed air between the supply line 13 and the tire 3.
To inflate the tire 3, the control valve 25 is opened by high pressure air supplied by the compressor C (or by an alternative compressed air reservoir) through the supply line 13. This step is represented by the raising pressure gradient at time t1 in
Deflation requires the supply air pressure to be raised again, briefly, above the valve operation threshold to open the control valve 25 to allow air to leave the tire cavity 4. The control valve 25 then needs to be operated again, briefly, in the same manner, i.e. by applying a supply air pressure above the valve operation threshold to close the control valve 25 to seal the tire cavity 4. The pressure of air in the tire cavity 4 is measured by a tire pressure monitoring system (TPMS) sensor (not shown) mounted on the wheel rim 11.
As depicted in
The operation of the control valve 25 will now be described in more detail with reference to the schematic representations shown in
During a normal running mode, no compressed air is supplied to the supply line 13 and the pressure in the supply line 13 is substantially equal to, or slightly above, atmospheric pressure. The poppet valve 84 is displaced to its closed position (as shown in
To operate in an inflate mode, full pressure is supplied to the inlet port 55 of the control valve 25. As shown in
To operate in a deflate/pressure check mode, the poppet valve 84 must be operated again in the same manner, i.e. by supplying full pressure, and then the pressure supplied to the inlet port 55 is reduced to tire pressure or below. The piston assembly 88 moves under the action of the piston spring 90 (to the left in the illustrated arrangement), but is stopped by the latch 91 and held in an intermediate position, as shown in
To reset the control valve 25, again full pressure is applied to the inlet port 55 and the piston assembly 88 is displaced against the action of the piston spring 90 (to the right in the illustrated arrangement). However, the piston assembly 88 is stopped by the latch 91 and the poppet valve 84 is prevented from lifting from the piston assembly 88. The control valve 25 thereby remains closed throughout the reset operation and the tire pressure does not change. Finally, the latch 91 rotates to its fourth position in preparation for returning to the normal run mode.
As described herein, the control valve assembly 7 is removably mounted in the hub cavity 37. When the vehicle wheel assembly 1 is installed on the vehicle, the control valve assembly 7 is fixed in position between the wheel hub 9 and the vehicle hub so that it rotates with the wheel when the vehicle in in motion. The control valve assembly 7 can only be removed once the vehicle wheel assembly 1 has been removed. In particular, the vehicle wheel assembly 1 is removed from the vehicle hub by undoing the wheel nuts (or bolts) and lifting the entire wheel assembly 1 off of the mounting bolts. The retaining clips 69, 71 are then squeezed together and released from the first annular recess 75 to enable the control valve assembly 7 to be removed from the wheel hub 9. The control valve assembly 7 is removed axially, along the rotational axis a-a towards the inner side of the vehicle wheel assembly 1. When the control valve assembly 7 is removed, the closure member 31 is lifted clear of the pin 53 and the valve member 43 is displaced to its closed position by the fluid pressure in the tire 3 and the bias applied by the spring 45. The wheel valve 39 is thereby closed and the transfer line 19 is sealed, inhibiting the venting of air from the tire 3 to atmosphere. The removal of the control valve assembly 7 facilitates routine maintenance and servicing, for example to replace the tire 3 and/or balance the vehicle wheel assembly 1. The tire 3 and the wheel 5 can be serviced according to conventional procedures after the control valve assembly 7 has been removed. Should the wheel 5 be damaged to an extent that the wheel 5 is no longer roadworthy, the wheel 5 can be replaced by any suitable conventional wheel. Vice versa, it will be understood that the wheel 5 can be mounted on any suitable vehicle not equipped with a CTIS, e.g. to replace a conventional wheel.
To assemble the vehicle wheel assembly 1, the control valve assembly 7 is located in the hub cavity 37 and displaced along the axis a-a until the retaining clips 69, 71 locate in the first annular recess 75. The closure member 31 engages the pin 53 and displaces the valve member 43 to its open position. The wheel valve 39 is thereby opened and fluid communication established between the tire 3 and the control valve 25. The second annular chamber 63 maintains fluid communication between the control valve 25 and the transfer line 19 irrespective of the angular orientation of the control valve assembly 7. The retaining clips 69, 71 help to prevent the control valve assembly 7 being displaced out of the hub cavity 37 due to the pressure increase when the wheel valve 39 is opened. The vehicle wheel assembly 1 can then be mounted to the vehicle hub. The nozzle 59 locates in the end of the drive shaft 15 and a seal is formed between the respective surfaces 66, 67. The vehicle wheel assembly 1 is secured in position by the wheel nuts (or bolts) in conventional manner.
Once installed, the control valve assembly 7 is operable to control the supply of compressed air from the compressor to the tire 3. Specifically, the control valve 25 is operable selectively to open and close the fluid pathway between the supply line 13 and the transfer line 19. In the present embodiment, the control valve 25 is actuated in response to changes in the pressure in the supply line 13. The control valve 25 comprises a latching mechanism which cycles through a sequence of operating modes to provide a normal operating mode; an inflate mode; a deflate/pressure check mode; and a reset mode. The ECU controls operation of the compressor C and/or the associated valve block VB to control the supply of compressed air to the supply line 13 to control operation of the control valve 25. It will be appreciated that the operating sequence of the control valve 25 could be changed with corresponding changes to the control strategy implemented by the ECU.
Although tire inflation operations have mostly been referred to in the above passages, it will be clear that the present invention can also be used in tire deflation modes, insofar as an appropriate control valve is used, for example one according to
A service valve such as a Schrader valve can be provided on the wheel to provide a conventional means of checking and adjusting tire pressure. The Schrader valve could be provided on the wheel rim 11 or in the hub, for example in communication with a second conduit. The Schrader valve could be positioned diametrically opposite the wheel valve 39 to help balance the wheel assembly 1.
Embodiments of the present invention can be used to take pressurized air made available at the vehicle axle to the tire 3. In the above passages, we have described: a specifically designed wheel 5; a specifically designed control valve assembly 7, and a vehicle wheel assembly 1 resulting from the assembly of the wheel 5 and the control valve assembly 7.
In the embodiment described previously, the in-wheel valve 39 has been provided to stop the tire from deflating once the control valve assembly 7 is removed from the wheel. The in-wheel valve 39 is actuated (held in the open state) when the control valve assembly 7 is fitted to the center of the wheel 5 by means of a mechanical action of a valve pin 53 being pressed down as the control valve assembly 7 is mounted to the wheel 5, thus opening the in-wheel valve 39. The in-wheel valve 39 thereby functions as an isolation valve which closes the transfer line 19 when the wheel 5 and the control valve assembly 7 are removed from the wheel hub, for example for tire fitting/balancing purposes. In a modified arrangement of the wheel assembly 1, this functionality is preserved but the location of the in-wheel valve 39 is changed. In particular, the in-wheel valve 39 is arranged such that the valve pin 53, which controls operation of the valve member 43, cooperates with the vehicle wheel hub rather than the control valve assembly 7. This modified arrangement, as illustrated in
The vehicle wheel hub assembly 100, in use, is held in a knuckle 101. The vehicle wheel hub assembly 100 conventionally comprises a hub mounting flange 102 having a plurality of threaded studs 104 for mounting the wheel assembly 1. In the embodiment illustrated in
In use, when the wheel assembly 1 is mounted to the vehicle wheel hub assembly 100, the hub mounting flange 102 engages the valve pin 53 and displaces the valve member 43 to its open position. The in-wheel valve 39 is thereby opened when the wheel assembly 1 is mounted to the vehicle hub. Conversely, when the wheel assembly 1 is removed from the vehicle wheel hub 100, the hub mounting flange 102 disengages from the valve pin 53 and the valve member 43 is returned to its closed position under the action of a coil spring 114. The in-wheel valve 39 is thereby closed when the wheel assembly 1 is removed from the vehicle wheel hub 100. The position of the valve pin 53 when disengaged from the hub mounting flange 102 is controlled by a pin protrusion 116 which abuts a stop 118 formed in the housing 112. In this modified arrangement, the removal or fitting of the control valve assembly 7 can be performed without actuating the in-wheel valve 39. The operation of the wheel assembly 1 is unchanged from that of the embodiment described previously.
It will be appreciated that the in-wheel valve 39 can be actuated by various means, including the fitting of the control valve assembly 7, and/or the fitting of the wheel assembly 1 to the vehicle.
Various alternative embodiments of the control valve assembly 7 and vehicle wheel assembly 1 exist. Those features in common with the aforementioned embodiment are not necessarily expressly described and those which are described are labelled 500 greater.
With reference to
With reference to
With reference to
With further reference to
In the installed location, the control valve assembly 507 is rotatable from the first orientation corresponding to an unlocked condition, to a second orientation corresponding to a locked condition, by clockwise movement of the control valve assembly 507.
In the first (unlocked) orientation, each boss 642 is aligned one of the lobes 636. In the second (locked) orientation, each boss 642 is aligned with the other lobes 638. When moving between the unlocked and locked orientations, the bosses 642 deflect inwardly by the ribs 640 then rebound to their neutral undeflected positions when aligned with the second lobes 638 in the locked orientation. When in the locked orientation, the control valve assembly 507 is prevented from separating axially from the wheel hub 509 since the bosses 642 are aligned with the overhangs 628. The rib 640, the overhang 628, and the shoulder 634 thus cooperate to secure the bosses 642 in the locked orientation.
In this way, the control valve assembly 507 includes features arranged to provide a locking mechanism for engagement with corresponding features in the wheel, in the form of a twist lock, which may be selectively engaged to lock or unlock the control valve assembly 507 within the wheel hub 509.
When the control valve assembly 507 is mounted within the wheel hub 509, the peripheral flange 620 forms a compliant ring providing a damping element to damp vibrations which may otherwise adversely affect the valve assembly 507.
With further reference to
With further reference to
With reference to
Still with reference to
With reference to
Regardless as to the configuration of the supply line filter 656 implemented in the nozzle 559, the nozzle 559 and the supply line filter 656 are integrally formed as a substantially monolithic structure. The nozzle 559 includes an annular flange 666 mounted within a groove 668 of the control valve. Since the nozzle 559 is made from a resilient material, the nozzle 559 can be removably and replaceably mounted to the control valve by deflection of the flange 666 passing through to the groove 668.
The nozzle 559 also includes finger grips 670 in the form of annular formations. The finger grips allow for easy removal by a user's fingers. Accordingly, there is no need for additional tooling to install and remove the nozzle 559 when replacement is required.
With reference to
With reference to
The peripheral flange 620 in fact forms a flange for constraining axial movement of an O-ring 684a between itself and the cage 624 (
At a side of the body 700 opposite the grip 670 is a throat 710. The throat has a smaller outer diameter than the annular wall, which outer diameter has a grooved surface for friction welding to the cap 702.
With reference to
The cap 702 includes inner 712 and outer 714 circumferential flanges extending radially outwardly. Inner flange 712 is arranged to constrain axial movement of an O-ring 684b (
These O-rings 684a, b, c (
With reference to
Each broken line A1, and A2, represent a flash-line, which flash-line results after separation of the mold tools. In this embodiment, there are two flash-lines. Flash-line A1 is a circumferential flash-line around the flange 620, which flash-line A1 is caused by the interface between the opposing mold tools. Flash-line A2 is an axial flash-line caused by interface between the radially separable mold parts. The rationale for fabricating the body in this way is due to the locality of the O-rings on the resultant body. Specifically, flash-lines are oriented to avoid contacting O-rings.
With reference to
Similar to
After molding, the modules 724, 726 are attached by welding, specifically ultrasonic welding. A dot-dash line B3 is shown in
With reference to
It can be seen from
The filter elements 682, and also the supply line filter 656 (
Number | Date | Country | Kind |
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1510054.8 | Jun 2015 | GB | national |
Filing Document | Filing Date | Country | Kind |
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PCT/EP2016/063136 | 6/9/2016 | WO | 00 |