Systems and methods for joining blade components of rotor blades
11125205 · 2021-09-21
Assignee
Inventors
- Daniel Alan Hynum (Simpsonville, SC, US)
- James Robert Tobin (Simpsonville, SC, US)
- Christopher Daniel Caruso (Greenville, SC, US)
- Aaron A. Yarbrough (Greenville, SC, US)
Cpc classification
B29C65/342
PERFORMING OPERATIONS; TRANSPORTING
Y02P70/50
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
B29C66/73772
PERFORMING OPERATIONS; TRANSPORTING
B29C65/4895
PERFORMING OPERATIONS; TRANSPORTING
B29K2023/00
PERFORMING OPERATIONS; TRANSPORTING
B29C66/14
PERFORMING OPERATIONS; TRANSPORTING
B29K2067/003
PERFORMING OPERATIONS; TRANSPORTING
B29C65/3468
PERFORMING OPERATIONS; TRANSPORTING
B29C65/06
PERFORMING OPERATIONS; TRANSPORTING
B29C66/12821
PERFORMING OPERATIONS; TRANSPORTING
B29C66/72141
PERFORMING OPERATIONS; TRANSPORTING
B29C66/12861
PERFORMING OPERATIONS; TRANSPORTING
B29K2031/04
PERFORMING OPERATIONS; TRANSPORTING
B29C66/1284
PERFORMING OPERATIONS; TRANSPORTING
B29K2027/08
PERFORMING OPERATIONS; TRANSPORTING
B29K2071/00
PERFORMING OPERATIONS; TRANSPORTING
B29K2077/00
PERFORMING OPERATIONS; TRANSPORTING
B29C66/7212
PERFORMING OPERATIONS; TRANSPORTING
B29C66/543
PERFORMING OPERATIONS; TRANSPORTING
B29K2081/04
PERFORMING OPERATIONS; TRANSPORTING
B29C66/71
PERFORMING OPERATIONS; TRANSPORTING
B29C65/7841
PERFORMING OPERATIONS; TRANSPORTING
B29K2079/085
PERFORMING OPERATIONS; TRANSPORTING
B29K2075/00
PERFORMING OPERATIONS; TRANSPORTING
Y02E10/72
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
B29K2069/00
PERFORMING OPERATIONS; TRANSPORTING
B29C66/73941
PERFORMING OPERATIONS; TRANSPORTING
B29C66/73773
PERFORMING OPERATIONS; TRANSPORTING
B29K2031/04
PERFORMING OPERATIONS; TRANSPORTING
B29K2081/06
PERFORMING OPERATIONS; TRANSPORTING
B29C65/40
PERFORMING OPERATIONS; TRANSPORTING
B29K2079/085
PERFORMING OPERATIONS; TRANSPORTING
B29K2001/00
PERFORMING OPERATIONS; TRANSPORTING
B29C66/73921
PERFORMING OPERATIONS; TRANSPORTING
B29C65/10
PERFORMING OPERATIONS; TRANSPORTING
B29K2067/006
PERFORMING OPERATIONS; TRANSPORTING
B29C65/20
PERFORMING OPERATIONS; TRANSPORTING
B29K2305/00
PERFORMING OPERATIONS; TRANSPORTING
F03D1/0675
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
B29K2081/04
PERFORMING OPERATIONS; TRANSPORTING
B29K2067/00
PERFORMING OPERATIONS; TRANSPORTING
B29C65/34
PERFORMING OPERATIONS; TRANSPORTING
B29K2063/00
PERFORMING OPERATIONS; TRANSPORTING
B29C66/73774
PERFORMING OPERATIONS; TRANSPORTING
B29K2067/006
PERFORMING OPERATIONS; TRANSPORTING
B29C65/04
PERFORMING OPERATIONS; TRANSPORTING
B29K2027/08
PERFORMING OPERATIONS; TRANSPORTING
B29K2027/00
PERFORMING OPERATIONS; TRANSPORTING
B29K2055/02
PERFORMING OPERATIONS; TRANSPORTING
B29C66/73771
PERFORMING OPERATIONS; TRANSPORTING
B29K2067/003
PERFORMING OPERATIONS; TRANSPORTING
B29K2077/00
PERFORMING OPERATIONS; TRANSPORTING
B29K2081/06
PERFORMING OPERATIONS; TRANSPORTING
B29C66/1122
PERFORMING OPERATIONS; TRANSPORTING
B29K2033/12
PERFORMING OPERATIONS; TRANSPORTING
B29K2075/00
PERFORMING OPERATIONS; TRANSPORTING
B29K2069/00
PERFORMING OPERATIONS; TRANSPORTING
B29C66/71
PERFORMING OPERATIONS; TRANSPORTING
B29K2067/00
PERFORMING OPERATIONS; TRANSPORTING
B29K2023/00
PERFORMING OPERATIONS; TRANSPORTING
B29C66/7212
PERFORMING OPERATIONS; TRANSPORTING
B29K2027/00
PERFORMING OPERATIONS; TRANSPORTING
B29K2071/00
PERFORMING OPERATIONS; TRANSPORTING
B29C66/0342
PERFORMING OPERATIONS; TRANSPORTING
B29K2001/00
PERFORMING OPERATIONS; TRANSPORTING
B29C66/636
PERFORMING OPERATIONS; TRANSPORTING
B29K2305/00
PERFORMING OPERATIONS; TRANSPORTING
B29K2055/02
PERFORMING OPERATIONS; TRANSPORTING
B29K2033/12
PERFORMING OPERATIONS; TRANSPORTING
International classification
Abstract
Systems and methods for joining blade components of a rotor blade are provided. A method includes positioning a first blade component and a second blade component such that a joint location of the first blade component and a joint location of the second blade component are proximate each other. The method further includes applying a force to an outer surface of the second blade component and an opposing force to an inner surface of the second blade component. The force and opposing force maintain an aerodynamic contour of the second blade component. The method further includes connecting the joint location of the first blade component and the joint location of the second blade component together.
Claims
1. A method for joining blade components of a wind turbine rotor blade, the method comprising: positioning a first pre-formed wind turbine blade component and a second pre-formed wind turbine blade component such that a joint location of the first pre-formed wind turbine blade component and a joint location of the second pre-formed wind turbine blade component are proximate each other; applying a force to an outer surface of the second pre-formed wind turbine blade component; inflating a bladder such that, when the bladder is inflated, the bladder directly contacts an inner surface of the second pre-formed wind turbine blade component to apply an opposing force to the inner surface, the force and the opposing force maintaining an aerodynamic contour of the second pre-formed wind turbine blade component; and heating the joint location of the first pre-formed wind turbine blade component and the joint location of the second pre-formed wind turbine blade component when the force is being applied to the outer surface and the opposing force is being applied to the inner surface by the bladder to weld the first pre-formed wind turbine blade component and the second pre-formed wind turbine blade component together.
2. The method of claim 1, wherein the force is applied by a fixture arm in contact with the outer surface of the second pre-formed wind turbine blade component.
3. The method of claim 2, wherein the fixture arm is rotatable about an axis of a fixture frame.
4. The method of claim 3, wherein applying the force comprises rotating the fixture arm about the axis.
5. The method of claim 2, wherein the fixture arm comprises a base and an insert removably connected to the base, the insert having a contact surface that conforms to the aerodynamic contour of the second pre-formed wind turbine blade component.
6. The method of claim 1, wherein the first pre-formed wind turbine blade component and the second pre-formed wind turbine blade component each comprise a thermoplastic resin.
7. The method of claim 1, wherein the heating step comprises heating a resistive heating element disposed proximate the joint location of the first pre-formed wind turbine blade component and the joint location of the second pre-formed wind turbine blade component such that heating of the resistive heating element heats the joint location of the first pre-formed wind turbine blade component and the joint location of the second pre-formed wind turbine blade component.
8. The method of claim 1, wherein second pre-formed wind turbine blade component is a wind turbine blade segment.
9. The method of claim 1, wherein the first pre-formed wind turbine blade component is one of a wind turbine blade root section, a wind turbine blade tip section, or a wind turbine spar cap.
10. The method of claim 1, wherein at least one of the first pre-formed wind turbine blade component or the second pre-formed wind turbine blade component comprises a thermoset resin and a localized portion of thermoplastic plastic resin.
11. The method of claim 1, wherein the first pre-formed wind turbine blade component and the second pre-formed wind turbine blade component are formed of a mixture of hardened resin and fibers.
12. A method for joining blade components of a wind turbine rotor blade, the method comprising: positioning a first pre-formed wind turbine blade component and a second pre-formed wind turbine blade component such that a joint location of the first pre-formed wind turbine blade component and a joint location of the second pre-formed wind turbine blade component are proximate each other, wherein the first pre-formed wind turbine blade component and the second pre-formed wind turbine blade component each comprise a thermoplastic resin; applying a force to an outer surface of the second pre-formed wind turbine blade component; inflating a bladder such that, when the bladder is inflated, the bladder directly contacts an inner surface of the second pre-formed wind turbine blade component to apply an opposing force to the inner surface, the force and the opposing force maintaining an aerodynamic contour of the second pre-formed wind turbine blade component; and heating the joint location of the first pre-formed wind turbine blade component and the joint location of the second pre-formed wind turbine blade component when the force is being applied to the outer surface and the opposing force is being applied to the inner surface by the bladder to weld the first pre-formed wind turbine blade component and the second pre-formed wind turbine blade component together.
13. The method of claim 12, wherein the force is applied by a fixture arm in contact with the outer surface of the second pre-formed wind turbine blade component.
14. The method of claim 13, wherein the fixture arm is rotatable about an axis of a fixture frame.
15. The method of claim 14, wherein applying the force comprises rotating the fixture arm about the axis.
16. The method of claim 13, wherein the fixture arm comprises a base and an insert removably connected to the base, the insert having a contact surface that conforms to the aerodynamic contour of the second pre-formed wind turbine blade component.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) A full and enabling disclosure of the present invention, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures, in which:
(2)
(3)
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DETAILED DESCRIPTION OF THE INVENTION
(12) Reference now will be made in detail to embodiments of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. For instance, features illustrated or described as part of one embodiment can be used with another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and their equivalents.
(13) Referring now to the drawings,
(14) Referring now to
(15) The pressure side, suction side, leading edge and trailing edge may be generally aerodynamic surfaces having generally aerodynamic contours, as is generally known in the art. Thus, the exterior surface of the rotor blade 16 may define an aerodynamic profile, such as an airfoil-like cross-sectional profile, for the rotor blade 16. The aerodynamic profile includes the pressure side, suction side, leading edge and trailing edge.
(16) The rotor blade 16 may, in some embodiments, be curved. Curving of the rotor blade 16 may entail bending the rotor blade 16 in a generally flapwise direction and/or in a generally edgewise direction. The flapwise direction may generally be construed as the direction (or the opposite direction) in which the aerodynamic lift acts on the rotor blade 16. The edgewise direction is generally perpendicular to the flapwise direction. Flapwise curvature of the rotor blade 16 is also known as pre-bend, while edgewise curvature is also known as sweep. Thus, a curved rotor blade 16 may be pre-bent and/or swept. Curving may enable the rotor blade 16 to better withstand flapwise and edgewise loads during operation of the wind turbine 10, and may further provide clearance for the rotor blade 16 from the tower 12 during operation of the wind turbine 10.
(17) The rotor blade 16 may further define a chord 23 and a span 25 extending in chord-wise and span-wise directions, respectively. The chord may vary throughout the span of the rotor blade 16. Thus, a local chord may be defined for the rotor blade 16 at any point on the rotor blade 16 along the span.
(18) Additionally, as shown in
(19) As shown in
(20) More specifically, as shown, the main blade structure 15 may include any one of or a combination of the following: a pre-formed blade root section 20, a pre-formed blade tip section 22, one or more one or more continuous spar caps 48, 50, 51, 53, one or more shear webs 35 (
(21) In some embodiments, as shown in
(22) In addition, as shown in
(23) Referring to
(24) More specifically, as shown in
(25) It should additionally be noted that, in some embodiments, a blade component may be a surface feature. A surface feature is generally a component added to a surface, such as an exterior surface, of the rotor blade 16 to modify flow characteristics, lift characteristics, etc. of the rotor blade 16. For example, a surface feature may be a vortex generator. Vortex generators may be utilized to reduce flow separation during operation of a rotor blade 16. In some embodiments, a vortex generator may be generally fin-like. Alternatively, a vortex generator may have any suitable shape.
(26) Additionally or alternatively, a surface feature may be a noise reducer. Noise reducers may be utilized to reduce noise generated by the wind flow over and away from a rotor blade 16. In some embodiments, a noise reducer may include a plurality of serrations. Additionally or alternatively, a noise reducer may include a plurality of bristles, or have any other suitable shape and/or configuration.
(27) Further, a surface feature may be a winglet. Winglets may be utilized to increase lift at the tip 72 of a rotor blade 16. Still further, a surface feature may be a root enhancer or other suitable chord extension apparatus. Root enhancers may be utilized to increase lift at the root 74 of a rotor blade 16.
(28) It should be understood that the present disclosure is not limited to the above disclosed surface features. Rather, any suitable device or apparatus configured on an exterior surface of a rotor blade 16 is within the scope and spirit of the present disclosure.
(29) As discussed, the various blade components of the rotor blade 16, such as the main blade structure 15 and/or the various blade segments 21, may include a thermoset resin and/or a thermoplastic resin. Thermoplastic resins as described herein generally encompass a plastic material or polymer that is reversible in nature. For example, thermoplastic resins typically become pliable or moldable when heated to a certain temperature and return to a more rigid, solidified state upon cooling. Further, thermoplastic resins may include amorphous thermoplastic resins and/or semi-crystalline thermoplastic resins. For example, some amorphous thermoplastic resins may generally include, but are not limited to styrenes, vinyls, cellulosics, polyesters, acrylics, polysulphones, and/or imides. More specifically, example amorphous thermoplastic materials may include polystyrene, acrylonitrile butadiene styrene (ABS), polymethyl methacrylate (PMMA), glycolised polyethylene terephthalate (PET-G), polycarbonate, polyvinyl acetate, amorphous polyamide, polyvinyl chlorides (PVC), polyvinylidene chloride, polyurethane, or any other suitable amorphous thermoplastic material. In addition, example semi-crystalline thermoplastic resins may generally include, but are not limited to, polyolefins, polyamides, fluropolymers, ethyl-methyl acrylate, polyesters, polycarbonates, and/or acetals. More specifically, exemplary semi-crystalline thermoplastic materials may include polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polypropylene, polyphenyl sulfide, polyethylene, polyamide (nylon), polyetherketone, or any other suitable semi-crystalline thermoplastic material. The thermoset resins as described herein generally encompass a plastic material or polymer that is non-reversible in nature. For example, thermoset resins, once cured, cannot be easily remolded or returned to a liquid state. As such, after initial forming, thermoset materials are generally resistant to heat, corrosion, and/or creep. Example thermoset materials may generally include, but are not limited to, some polyesters, some polyurethanes, esters, epoxies, or any other suitable thermoset materials.
(30) Referring briefly to
(31) Referring now to
(32) In accordance with the present disclosure, a first blade component 100 and a second blade component 110 may be joined together. Referring to
(33) First blade component 100 may be any suitable component of main blade structure 15, such as root section 20, tip section 22, or a spar cap 48, 50, 51, 53, or may be any suitable blade segment 21, such as a leading edge segment 24, trailing edge segment 26, etc. Second blade component 100 may similarly be any suitable component of main blade structure 15, such as root section 20, tip section 22, or a spar cap 48, 50, 51, 53, or may be any suitable blade segment 21, such as a leading edge segment 24, trailing edge segment 26, etc. In some exemplary embodiments, such as for example, illustrated in
(34)
(35) A second fixture 220 for supporting the second blade component 110 is additionally illustrated. Fixture 212 may be used to arrange and/or orient the blade component 110 of the rotor blade 16 for joining with the first blade component 100. For example, as shown, the fixture may include a fixture frame 222, which may for example include a plurality of beams connected together. Fixture frame 222 may be configured to support and orient the blade component 110, which in the embodiment shown is a blade segment 21, such as a leading edge segment 24.
(36) Fixture 220 (as well as fixture 210) may additionally include features for maintaining the aerodynamic contour of the blade components 100, 110 during joining thereof. For example, as illustrated, fixture 220 may include one or more arms 224 that are connected to the frame 220 and which contact the outer surface 114 of the blade component 110. When the blade component 110 is placed in the fixture 220, portions of the outer surface 114 thereof may contact the arms 224.
(37) In exemplary embodiments as illustrate, arms 224 may be rotatable about axes 226 of the frame 222. The axes 226 may, for example, be span-wise extending axes 226. Such rotation may facilitate placement of the blade component 110 in the fixture 220 and further facilitate the application of a force to the blade component 110, as discussed herein.
(38) Referring to
(39) Further, in exemplary embodiments, the inserts 232 may be removable and interchangeable. For example, each insert 232 being removably connectable to the base 230 and/or frame 222. The contact surface 236 of each insert 232 may have a different aerodynamic contour which corresponds to the aerodynamic contour of the outer surface 114 of a different blade component 110. Three inserts 232, 232′, 232″ are illustrated, with each having a contact surface 236 with a different aerodynamic contour. For example, insert 232 may correspond to the aerodynamic contour of the outer surface of leading edge segment 24, insert 232″ may correspond to the aerodynamic contour of the outer surface of trailing edge segment 26, and insert 232′ may correspond to the aerodynamic contour of another suitable blade segment 21 or blade component 110. A suitable insert 232, 232′, 232″ may be connected to the base 230 and/or frame 222 to correspond to the blade component 110 being supported and joined to blade component 100.
(40) Referring now to
(41) Fixture 200 may further include one or more electrical connectors 242 which may be configured for connecting to heating elements 244 as discussed herein. The heating elements 244 may, for example, be heated to join the blade components 100, 110. Electricity may be provided to the heating elements 244 by the electrical connectors 242, and may be provided to the electrical connectors 242 by a power source 246.
(42) It should be understood that the present disclosure is not limited to thus use of such fixture components for the second blade component 110. Rather, such fixture components may additionally be utilized to support first blade component 100 and maintain the aerodynamic contour of the first blade component 100 as well if required or desired.
(43) Referring now to
(44) Method 300 may further include, for example, the step 320 of applying a force 322 to the outer surface 114 of the blade component 110 and an opposing force 324 to the inner surface 112 of the blade component 110. The direction of the force 322 may, for example, be towards the inner surface 112, and the direction of the opposing force 324 may, for example, be towards the outer surface 114. Any suitable components may be utilized to apply the forces 322, 324. In exemplary embodiments, the force 322 may be applied by the fixture arm(s) 224. In some embodiments, for example, the arm(s) 224 may be rotated into position in contact with the outer surface 114, and may be positioned such that a desired force 322 is being applied to the outer surface 114. In other embodiments, the arm(s) 224 may be fixed, and the force 322 may be applied as a reaction to the force 324. In exemplary embodiments, the force 324 may be applied by the inflatable bladder 240. Alternatively, the force 324 may be applied by any suitable fixed or movable fixture component, such as a cradle, arm, or other suitable component.
(45) Advantageously, the force 322 and force 324 may maintain the aerodynamic contour of the blade component 110 during joining of the blade components 100, 110 together. For example, the forces 322, 324 may support the blade component 110 in place during joining, thus reducing or preventing movement of the blade component 110 and potential deformation of the outer surface 114 and loss of aerodynamic contour during joining.
(46) Method 300 may further include, for example, the step 330 of connecting the joint location 106 and the joint location 116 together. In exemplary embodiments, the connecting step 330 may include welding of the joint locations 106, 116 together. For example, as discussed, the rotor blade 16 may include a thermoplastic resin. The thermoplastic resin may be included in the blade components 100, 110 and joint locations 106, 116 thereof. A blade component 100, 110 may thus include, and be formed at least partially from, a thermoplastic resin. In some embodiments, the resin may be a neat resin which is free from fibers. In other embodiments, the blade components may include fiber reinforced thermoplastic composites, which may include the thermoplastic resin and a plurality of fibers embedded in the thermoplastic resin as discussed herein.
(47) Notably, a blade component may in exemplary embodiments be formed from a plurality of layers, or plies. One or more of the plies may thus include the thermoplastic resin and/or composite as discussed.
(48) In some embodiments, an entire blade component may include the thermoplastic resin (and, optionally, composite including the thermoplastic resin and fibers). Alternatively, only one or more localized portions of a blade component may include the thermoplastic resin (and, optionally, composite including the thermoplastic resin and fibers). For example, one or more localized portions may include the thermoplastic resin, while the remainder of a blade component may include a thermoset resin (and, optionally, a composite which includes the thermoset resin and fibers embedded therein). At least one localized portion may be a joint portion which is utilized to form a joint connecting a blade component to a mating blade component.
(49) Welding may include welding the thermoplastic resin of the blade components 100, 110 together, such as at the joint locations 106, 116 between the components 100, 110 when aligned proximate each other. Any suitable welding process may be utilized to weld the blade components together. For example, suitable welding techniques may include resistive welding, hot gas welding, speed tip welding, extrusion welding, contact welding, hot plate welding, high frequency welding, induction welding, injection welding, ultrasonic welding, friction welding, laser welding, or solvent welding.
(50) In exemplary embodiments, welding may include heating the thermoplastic resins of the blade components, such as at the joint locations 106, 116. For example, as discussed, a heating element 244, such as a resistive heating element 244, may be provided between the blade components 100, 110, such as between the joint locations 106, 116. The heating element 244 may, for example, be embedded in one of the blade components 100, 110, such as at the joint location 106, 116 thereof or may be disposed on the surface of one of the blade components 100, 110, such as at the joint location 106, 116 thereof. Electrical connector(s) 242, which may for example be conductive wires or other suitable components configured to transmit electricity therethrough, may be connected to the heating element 244. The electrical connectors 242 may be connected to a power source 246 from which the electrical connectors 242 receive electricity. Electricity being transmitted from the electrical connectors 242 to the heating element 244 may cause the heating element 244 to heat up, thus heating the thermoplastic resins of the blade components, such as at the joining location between the blade components. The resins may, for example, be heated to above the melting points of the resins in order to facilitate joining thereof via welding.
(51) To further facilitate welding, in exemplary embodiments, the rotor blade 16 (such as the blade components 100, 110 thereof), such as the thermoplastic resins thereof, may be cooled, such as after heating. Cooling allows the resins to re-solidify and the bonds between the blade components to be completed at the interface therebetween. In some embodiments, cooling is performed by simply allowing the rotor blade 16 (and blade components 100, 110 thereof) to rest in an ambient temperature environment. In other embodiments, suitable active cooling techniques utilizing cooled air or another suitable gas or liquid may be utilized.
(52) Methods for assembling rotor blades 16 in accordance with the present disclosure provide numerous advantages. In particular, methods in accordance with the present disclosure facilitate efficient and cost-effective rotor blade 16 assembly. Further, the aerodynamic contours of the various pre-formed blade components can be advantageously maintained during joining together with other pre-formed blade components to form the rotor blade 16.
(53) This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.