Abstract:
A reconfigurable vehicle power and signal distribution system ( 10 ) is disclosed. The system comprises at least one conduit section ( 11 ) for housing a first and second power rail ( 22 ), and a communication line ( 20 ) for communicating signals along the conduit. The system further comprises a transfer hub ( 27 ) which enables the transfer of power and signals to a distribution hub that comprises a plurality of terminals for separately providing conditioned power to various system modules of the vehicle. The distribution of power from the distribution hub is dependent on signals received from a control unit via the communication line, which controls the power usage within the vehicle. The system enables the at least one conduit section, transfer hub and distribution hub to be reconfigured according to the topography of the vehicle.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a U.S. National-Stage entry under 35 U.S.C. §371 based on International Application No. PCT/GB2010/051033, filed Jun. 22, 2010 which was published under PCT Article 21 (2) and which claims priority to British Application No. 0910824.2, filed Jun. 23, 2009, which are all hereby incorporated in their entirety by reference. 
     
    
     TECHNICAL FIELD 
       [0002]    The technical field relates to a reconfigurable vehicle power and signal distribution system. 
       BACKGROUND 
       [0003]    Military fighting vehicles, such as tanks and personnel carriers of the wheeled and tracked variety, are equipped with various vehicle system modules to provide for example, power, communication, air conditioning and vehicle control. These modules are typically mounted internally and externally on the vehicle at distributed locations around the vehicle and are connected together via extensive wiring. As a result, it can be difficult to trace a failure of a particular module component, replace modules with up-dated or different modules and re-position modules within the vehicle. In addition, it is a difficult, time-consuming task to provide bespoke power and signals to modules having different functionality and which operate at different power ratings. 
         [0004]    Existing wiring systems are often left exposed within a vehicle and as such, it is common for wires to become damaged or pulled from their respective connection as personnel and equipment move within the vehicle. Moreover, since the wiring systems are often unique for a particular vehicle and/or function, it is difficult to reconfigure a vehicle for a different function, such as to reconfigure a military patrol vehicle to operate and function as an ambulance. 
         [0005]    In view of the foregoing, it is desirable to provide a reconfigurable vehicle power and signal distribution system which alleviates the above-mentioned problems. In addition, other desirable features and characteristics will become apparent from the subsequent summary and detailed description, and the appended claims, taken in conjunction with the accompanying drawings and this background. 
       SUMMARY 
       [0006]    In accordance with a first embodiment, there is provided a reconfigurable vehicle power and signal distribution system, the system comprising at least one conduit section for housing a first and second power rail, and a communication line for communicating signals along the at least one conduit section, the system further comprising a transfer hub which enables the transfer of power and signals to a distribution hub, the distribution hub comprising a plurality of outlets for separately providing conditioned power to various system modules of the vehicle, the distribution of power from the distribution hub being dependent on signals received from the communication line. The system permits a reconfiguration of the at least one conduit section, transfer hub and distribution hub according to the topography of the vehicle. 
         [0007]    Preferably, the at least one conduit section and transfer hub are detachably connectable. In accordance with an embodiment, the one or more conduit sections are preferably further detachably connectable with each other, and may be of different length and/or shape to accommodate the contours of the vehicle. The system thus enables an implementation of different electronic architectures depending on vehicle requirements, through a reconfiguration of the at least one conduit section, transfer hub and the distribution hub. 
         [0008]    The operational state of each of the plurality of outlets is dependent on signals received from the communication line. Preferably, the outlets are arranged to provide power at a selected voltage rating. 
         [0009]    Preferably, the at least one conduit section comprises a cover which is detachably securable to a body of the respective conduit section to provide easy access to an interior of the conduit section. 
         [0010]    The communication line of each conduit section preferably comprises a first connector disposed at a first end thereof and a second connector disposed at a second end thereof for connecting with adjacent conduit sections and/or a transfer hub of the system. 
         [0011]    The transfer hub preferably comprises power transfer rails and a communication transfer line for connecting the power rails and communication line of a first conduit section to, power rails and a communication line respectively, of a second conduit section. Preferably, the transfer hub comprises a plurality of connectors for connecting to the power rails and communication line of the first and second conduit sections. 
         [0012]    Preferably, the plurality of connectors comprise first and second connectors, such as male and female type connectors. 
         [0013]    The at least one conduit section, transfer hub and distribution hub preferably comprise a body formed of a rigid material, such as a composite, a metal or a plastic. The body preferably provides a low electrical resistance path to a hull or chassis of the vehicle to provide an electrical earth for the system modules. 
         [0014]    The transfer hub preferably further comprises a power terminal for transferring power to the system modules and/or the distribution hub. The transfer hub further comprises communication terminals for communicating signals between the communication line associated therewith to system modules and/or the distribution hub, and other devices connected to the transfer hub, such as video surveillance devices, computer device and communications equipment. 
         [0015]    Preferably, the distribution hub comprises a power terminal for receiving power from the transfer hub, and a communication terminal for receiving signals from the transfer hub. 
         [0016]    Preferably, the at least one conduit section houses a plurality of communication lines, each line being electromagnetically shielded by shielding means, which minimizes any interference on or between the communication lines. A shield also minimizes crosstalk between communication lines, the pickup of electromagnetic radiation from sources external to the conduit section and further minimizes the detection or interception of signals along the communication lines, by systems external to the system. 
         [0017]    In accordance with an embodiment, the shield preferably comprises a plurality of channels extending along the conduit, each channel being arranged to receive one of the plurality of communication lines. Preferably, each channel comprises an opening along a longitudinal side thereof for receiving a communication line and which is arranged to be closed via a closure. 
         [0018]    The power rails are preferably powered from a power source such as a power distribution unit, vehicle battery or generator. The power rails preferably comprise a first and second bar which are separately disposed in a channel which extends along the conduit. The channels are preferably arranged to electrically insulate the power rails from each other thereby preventing any electrical arcing between the power rails. 
         [0019]    In an alternative embodiment, the power rails preferably comprise a first and second substantially planar rail which are substantially encapsulated in an electrical insulation material forming a laminate structure. In accordance with this alternative embodiment, the plurality of communication lines are preferably disposed upon a printed circuit board and comprise a plurality of so-called strip-line pairs. The strip-line pairs preferably separately extend along the printed circuit board within a channel defined between opposing ground plates and vertical interconnect access or VIA connections that serve to electrically shield the strip line pairs. 
         [0020]    Preferably, the distribution hub comprises a conditioner and/or converter configured to condition and/or convert the power from said power rails and for delivering the power to one or more outlets provided on the distribution hub. The conditioning of power preferably comprises at least one of providing power at a different power rating at a plurality of outlets, switching the power to each outlet on and off, monitoring voltage and current levels, and the filtering of voltage and current signals. 
         [0021]    Preferably, the distribution hub comprises a switch controlled via signals received from said communication line, the switch arranged to control the power supplied to said one or more outlets provided on the distribution hub. 
         [0022]    In accordance with a second embodiment there is provided a vehicle power and signal distribution system, the system comprising a conduit for housing a first and second power rail, and a communication line for communicating signals along the conduit, the system further comprising a transfer hub which enables the transfer of power and signals to system modules of the vehicle. The conduit further comprises a shield for shielding said communication line to minimize interference on the line. 
         [0023]    Preferably, the system permits a reconfiguration of the conduit and transfer hub according to the topography of the vehicle. 
         [0024]    The system preferably further comprises a distribution hub for providing conditioned power to various system modules of the vehicle. 
         [0025]    The conduit preferably comprises a plurality of conduit sections. 
         [0026]    Further, preferred features of the second aspect may comprise one or more of the features of the first embodiment. 
         [0027]    In accordance with a third embodiment, there is provided a reconfigurable vehicle power and signal distribution system, the system comprising a conduit for housing a first and second power rail, and a communication line for communicating signals along the conduit, the system further comprising a transfer hub which enables the transfer of power and signals to system modules of the vehicle. The system permits a reconfiguration of the conduit and transfer hub according to the topography of the vehicle. 
         [0028]    The transfer hub further enables the transfer of power and signals to a distribution hub, the distribution hub comprising a plurality of outlets for separately providing conditioned power to various system modules of the vehicle. Preferably, the distribution of power from the distribution hub is dependent on signals received from the communication line. 
         [0029]    The conduit preferably comprises a plurality of conduit sections. 
         [0030]    Further preferred features of the third embodiment may comprise one or more of the features of the first and/or second embodiment. 
         [0031]    In accordance with a fourth embodiment there is provided a vehicle comprising a vehicle power and signal distribution system according to the first, second or third embodiment and a control unit for controlling the operation of the system. 
         [0032]    Preferably, the vehicle comprises a military vehicle, such as an armored fighting vehicle or armored personnel carrier. 
         [0033]    Further preferred features of the fourth embodiment may comprise one or more of the preferred features of the first, second, and/or third embodiment. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0034]    Embodiments will now be described by way of an example only and with reference to the accompanying drawings, in which: 
           [0035]      FIG. 1  is a schematic illustration of a vehicle power and signal distribution system in accordance with a first embodiment; 
           [0036]      FIG. 2  is a cross-sectional view through a conduit of the system of  FIG. 1 ; 
           [0037]      FIG. 3  is an exploded view of a conduit section according to a second embodiment; 
           [0038]      FIG. 4  is a magnified view of the connectors disposed at one end of the conduit section illustrated in  FIG. 3 ; and 
           [0039]      FIG. 5  is a sectional view across a transfer hub for connecting conduit sections according to the second embodiment. 
       
    
    
     DETAILED DESCRIPTION 
       [0040]    The following detailed description is merely exemplary in nature and is not intended to limit the application and uses. Furthermore, there is no intention to be bound by any theory presented in the preceding background or summary or the following detailed description. 
         [0041]    Referring to  FIG. 1  and  FIG. 2  of the drawings, there is illustrated a vehicle power and signal distribution system  10  according to an embodiment for a military vehicle, such as a tank or armored personnel carrier (not shown). The system  10  comprises a conduit divided into a plurality of conduit sections  11  which are substantially rectangular in cross-section and which are formed of a metal, such as aluminum, steel or a rigid electromagnetic compatible plastic material, which are intended to protect the component members of the conduit and provide an electrical earth to a vehicle hull or chassis (not shown). Each conduit section  11  comprises a housing  12  having a channel formed therein which is open at a front side, and which is closed by a detachable cover  13  which extends longitudinally of the conduit section  11 . The cover  13  is detachably coupled to the respective housing  12  via a plurality of fasteners (not shown), such as a plurality of clips (not shown), which enable the cover  13  to be readily coupled and uncoupled from the housing  12 . The conduit sections  11  may be linear in shape or angular for example, to match the interior contours of a vehicle  37 . 
         [0042]    According to a first embodiment, the conduit sections  11  comprise an insert  14 , which is substantially comb-like in cross-section and which is formed of a metal, such as aluminum. The insert  14  comprises a base  15  which is arranged to extend along the length of the conduit section  11  and a plurality of fingers  16  which extend from the base  15 . When the insert  14  is placed within the conduit section  11  with the fingers  16  extending away from the open front wall of the conduit body section  12 , the base  15  of the insert  14  divides the interior of the conduit section  11  into first and second longitudinally extending regions  17 ,  18 . 
         [0043]    The first region  17  comprises the plurality of fingers  16  which extend from the base  15  substantially parallel to each other and which define a plurality of channels  19  therebetween, which extend along the conduit section  11 . Each channel  19  is arranged to separately receive a communications line  20 , such as a communication wire or optical fiber, for communicating signals along the conduit section. In this manner, each communication line  20  is surrounded by the channel fingers  16 , base  15  and conduit body section  12 . It will be appreciated that each communication line  20  comprises a metallic or otherwise electromagnetic shield surround and as such, each channel  19  becomes electromagnetically isolated from other channels  19  and the surrounding environment, which thus serves to minimize electromagnetic interference in the respective communication lines  20 . 
         [0044]    The second section  18  comprises a carrier  21  of insulating plastics material, such as nylon, which is substantially W-shaped in cross-section, and which comprises a first and second receptacle  21   a,    21   b.  Each conduit section  11  comprises several carriers  21  disposed along the length of the conduit section  11  and are mounted upon the base  15  of the insert  14 . The receptacles  21   a,    21   b  of the carriers  21  are arranged to separately receive a positive and negative power rail  22   a,    22   b,  and are closed by a plastic, for example nylon, lid  23  which is arranged to extend over the power rails  22   a,    22   b.  The carriers  21  and lids  23  serve to insulate the power rails  22  from the insert  14  and the body  12  of the conduit section  11  and suitably support the power rails  22  within the conduit section  11 . The lid  23  is spaced from the interior of the conduit cover  13  by a layer  24  of electromagnetic compatible material which further helps to minimize any transmission of electromagnetic radiation into and from the conduit section  11 . 
         [0045]    The power rails  22  are formed of copper and are substantially rectangular in cross-section. The cross-sectional area is substantial and is sized so that the power rails  22  can withstand currents greater than 1000 A without failure or breakdown. Opposite longitudinal ends of each power rail  22  and communication line  20  comprise a first and second connector respectively, such as a male and female connector  25 ,  26 , which permit the power rails  22  and communication lines  20  to be readily connected with power rails  22  and communication lines  20  of further conduit sections  11 . 
         [0046]    Referring to  FIG. 3  and  FIG. 4  of the drawings, there is illustrated a conduit section  111  according to a second embodiment. The conduit section  111  of the second embodiment is similar to the conduit section  11  of the first embodiment and so like features have been referenced using the same numerals but increased by 100. 
         [0047]    The conduit section  111  illustrated in  FIG. 3  of the drawings comprises a housing  112  having a peripherally extending wall  112   a  which defines a channel therebetween. The conduit section  111  is open at a front side and is closed by a detachable cover  113  which extends longitudinally of the conduit section  111 . The cover  113  is detachably coupled to the respective body  112  via a plurality of fasteners (not shown), such as a plurality of clips (not shown), which enable the cover  113  to be readily coupled and uncoupled from the conduit body  112 . The conduit sections  111  may be linear in shape or angular for example, to match the interior contours of a vehicle  37 . 
         [0048]    The conduit section  111  comprises a plurality of coupling points  139  disposed along the length of the channel, for securing the power rails  122   a,    122   b  and communication lines  120  within the channel to thus minimize damage induced by sudden impacts upon the conduit section  111  and/or vehicle vibration. The power rails  122   a,    122   b  of the conduit section  111  comprise a first and second substantially planar rail which are encapsulated with an electrical insulation material (not shown) to form a laminate structure. The insulation material is arranged to withstand electrical and thermal breakdown associated with currents up to approximately 1000 A on the power rails  122   a,    122   b  for example and further protect the planar rails  122   a,    122   b  from environmental corrosion. 
         [0049]    The planar rails  122   a,    122   b  extend to each distal end of the housing  112  within the channel and separately terminate at a plurality of electrical connectors  125 ,  126 . The electrical connectors  125 ,  126  are disposed in rows at each longitudinal end of the body section  112 , and are disposed substantially upstanding on the respective planar rail  122   a,    122   b.  The first planar rail  122   a  which may comprise an electrically positive polarity for example, is arranged to extend to the outermost row of connectors  125  at each longitudinal end of the body section to provide for a series of positive electrical power connectors  125 . In contrast, the second planar rail  122   b  which may comprise an electrically negative polarity for example, is arranged to extend to the innermost row of connectors  126  at each longitudinal end of the body  112  to provide for a series of negative electrical power connectors  126 . 
         [0050]    The electrical communication lines  120  of the conduit section  111  are realized upon a substantially planar printed circuit board  139  which is arranged to extend over the laminate structure of power rails  122   a,    122   b  within the housing  112 . The printed circuit board  139  comprises a laminate structure of plurality of ground plates (not shown) interspersed with a layer of electrically insulating material (not shown). The printed circuit board  139  further comprises a plurality of vertical interconnect access or VIA connections (not shown) which extend between the ground plates (not shown), along the length thereof, such that the ground plates and VIA connections define a plurality of electrically shielded channels to minimize crosstalk between communication lines  120 , etc. The printed circuit board  139  further comprises a plurality of connectors  140  disposed at each longitudinal end thereof to provide for the coupling of the communication lines  120  to communications lines  120  of other conduit sections  111 . 
         [0051]    In addition to the printed circuit board  139 , the conduit section  111  may comprise a flexible cable harness (not shown) for retaining a plurality of optical communication lines (not shown) and/or electrical communication lines (not shown). Referring to  FIG. 4  of the drawings, the optical communication lines (not shown) may comprise a plurality of optical fibers (not shown), for example, which are terminated at each longitudinal end of the conduit section  111  by a series of optical connectors  141 . 
         [0052]    The laminate arrangement of power rails  122   a,    122   b  and the communication lines  121 , namely those associated with the printed circuit board  140  and the flexible wire harness (not shown) are held separated from each other within the conduit section  111  by an insulating material (not shown) which serves to minimize the transfer of thermal energy between the power rails  122   a,    122   b  and the communication lines  121 . The conduit section  111  further comprises a layer of electromagnetic absorbent material (not shown) which further helps minimize any transmission of electromagnetic radiation between the power rails  122   a,    122   b  and the communication lines  121 . 
         [0053]    The cover  113  is sized and shaped to substantially cover the channel formed within the housing and comprises a peripherally extending channel (not shown) formed on the underside thereof, which is arranged to receive a peripherally extending projection  142  disposed on an upper edge of the wall  112   a  of the housing  112 . The cooperation of the channel (not shown) on the cover  113  and the projection  142  serves to minimize any electromagnetic radiation from passing between the cover  113  and the upper edge of the wall  112   a  of the housing  112  and thus serves to electromagnetically seal the conduit section  111  from the outside environment. The cover  113  further comprises an aperture  143  disposed at each longitudinal end thereof to enable access and thus connection to the connectors  125 ,  126  on the planar rails  122   a,    122   b,  the electrical connectors on the printed circuit board  140  and the optical connectors  141  of the optical fibers (not shown). 
         [0054]    The conduit sections  11 ,  111  of the first and second embodiment are interspersed with a plurality of transfer hubs  27 . Each transfer hub  27  is arranged to channel power and communication signals from the power rails  22 ,  122  and communication lines  20 ,  120  of the conduit sections  11 ,  111  respectively, to other conduit sections  11 ,  111  and various vehicle system modules  36 , such as a radio communications module associated with the vehicle  37 . Power is supplied to the power rails  22 ,  122  from a battery supply  38  within the vehicle  37 . The power is delivered to the various transfer hubs  27  through the power rails  22 ,  122  as a 28V dc supply; however, it will be appreciated that other ac or dc voltages may also be used. Since this 28V dc supply may not be an optimal rating for the various modules  36 , the power from each transfer hub  27  may be passed via a power terminal  28  to a distribution hub  29  via a power connection cable  30 . 
         [0055]    The distribution hub  29  comprises a plurality of outlets  31 , and is arranged to condition the power supply to each outlet  31  so that separate outlets  31  provide an alternative voltage supply, for example, 5V, 12V, 24V etc. The conditioning however, may alternatively or additionally comprise filtering of the voltage and current on the power rails and/or monitoring the voltage and/or current levels. It is also envisaged that the conditioning may further comprise the provision of a fuse or switch to selectively isolate power from selected outlets. 
         [0056]    The distribution hub  29  is further arranged to receive signals from a control unit  32  via one or more of the communication lines  20 ,  120  via a control area network or CAN bus  33 , for example: the CAN bus  33  is one of the communication lines that is used in controlling the operational state of each outlet  31 . In this manner, it is possible to control the on/off state of each outlet  31  to control the power distribution within the system  10 . The transfer hub  27  may comprise further connections, such as an Ethernet connection  34  or a video connection  35  for example. 
         [0057]    The control signals are passed along the communication lines  20 ,  120  from the control unit  32  which may be operated by vehicle personnel (not shown). The control unit  32  permits various modules  36  to be switched on or off, as required in order to conserve power, for example or operate in a particular mode, such as a quiet or stealth mode. 
         [0058]    The system of conduit sections  11 ,  111  and transfer hubs  27  permit a reconfigurable arrangement of power and data distribution within a vehicle  37  to suit a particular vehicle function or vehicle interior. In use, the conduit sections  11 ,  111  are mounted within a vehicle  37  and connected together using the transfer hubs  27 . Various conduit sections  11 ,  111  having a variety of sizes and configurations may be employed so that the conduit extends around the desired contour of the interior of the vehicle  37 . The conduit sections  11 ,  111  are connected in series with one or more transfer hubs  27  via the connectors  25 ,  125 ,  26 ,  126  disposed thereon to form a loop or ring configuration. It is envisaged that such a configuration will provide a level of redundancy since the ring will provide for two paths of connectivity to the required module. 
         [0059]    Referring to  FIG. 5  of the drawings, there is illustrated a sectional view across a transfer hub  27  which is used to bridge the connectors  125 ,  126 ,  140 ,  141  disposed at one end of one conduit section  111   a  according to the second embodiment, with the connectors disposed at the other end of a second conduit section  111   b,  also according to the second embodiment. 
         [0060]    The transfer hub  27  comprises a body  44  which is arranged to couple with the first and second conduit sections  111   a,    111   b  and provide an electromagnetic seal with the respective conduit sections  111   a,    111   b.  The body  44  of the transfer hub  27  as illustrated in  FIG. 5  of the drawings, comprises a first and second chamber  45   a,    45   b  having respective side walls  46 , which are separately arranged to couple around the aperture  143  disposed at one end of the first conduit section  111   a  and the aperture  143  disposed at the other end of the second conduit section  111   b.  This coupling may be achieved using fasteners such as clips or nuts and bolts (not shown) for example and serves to electromagnetically seal the interior of the system from the surrounding environment. The transfer hub  27  further comprises power transfer rails  47   a,    47   b  and communication transfer lines (not shown), similar to the conduit sections  111  but of a reduced length, which extend between the chambers  45   a,    45   b  of the transfer hub  27 . The transfer hub  27  further comprises connectors  48 ,  49  disposed within the chambers  45   a,    45   b  which extend from the power transfer rails  47   a,    47   b  and the communication transfer lines (not shown) respectively, and which are adapted to connect with the respective connectors  125 ,  126 ,  140 ,  141  disposed at the longitudinal ends of the respective conduit sections  111   a,    111   b  to enable the transfer of power and communication signals from one conduit section  111   a  to the other  111   b.    
         [0061]    The transfer hubs  27  serve to provide power and data break out points along the conduit, so that external devices can take power from the power rails  22   a,    122   a,    22   b,    122   b  and so that signals to and/or from the vehicle modules (not shown) can be carried along the communication lines  20 ,  120 . 
         [0062]    The power is supplied to the power rails  22   a,    122   a,    22   b,    122   b  of the system  10  from a power distribution unit, such as a vehicle battery  38  or generator, and may be distributed from each transfer hub  27  via a distribution hub  29 , which is connected to the respective transfer hub  27  via the power connection cable  30  and CAN line  33 . The system modules  36  can then be connected with the appropriate outlet  31  on the distribution hub  29  and to the transfer hub  27  using the appropriate communication terminal  34 . 
         [0063]    Once the system has been installed within the vehicle  37 , vehicle personnel (not shown) can then control the various outlets  31  on the distribution hub  29  by sending signals from the control unit  32  to the respective transfer hub  27  and distribution hub  29  via the communication lines  20  and CAN line  33 . If required, the power supply to selected distribution hubs  29  and/or selected outlets  31  on a particular distribution hub  29  can then be switched off to conserve power for example or to conform with a particular mode of vehicle operation, such as quiet mode. If necessary, the conduit sections  11  may be uncoupled from each other and/or the transfer hubs  27  and re-routed within the vehicle  37  to accommodate the addition or removal of system modules  36 , for example. 
         [0064]    It is envisaged that the vehicle power and signal distribution system may further support the distribution of conditioned air within the vehicle  37  to provide for a comfortable environment for the occupants (not shown) and for controlling the temperature of the components of the system. In this respect, it is envisaged that the conduit sections  111  and transfer hubs  27  will provide a suitable duct for the transfer of conditioned air around the vehicle  37 . It is further envisaged that the conduit sections  111  may provide a suitable support for lighting within the vehicle  37 , for example. 
         [0065]    From the foregoing therefore, it is evident that the system provides a simple yet versatile means of reconfiguring the distribution of control, power and communication signals around a vehicle. Moreover, while at least one exemplary embodiment has been presented in the foregoing summary and detailed description, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient road map for implementing an exemplary embodiment of the invention, it being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope as set forth in the appended claims and their legal equivalents.