EXTERNAL GEAR AND ROTOR HYBRID PUMP

Abstract

Apparatuses and methods are provided for a hybrid gear-and-rotor pump. A pump includes a faceplate assembly, a backplate assembly, a main case with a chamber, and a hybrid gear-and-rotor assembly. The hybrid gear-and-rotor assembly includes a first shaft and a second shaft. The first and second shafts are configured to extend through the chamber into bores in the faceplate and backplate assemblies. The first shaft includes a first gear and a first rotor mounted for rotation on the first shaft within the chamber. The second shaft includes a second gear and a second rotor mounted for rotation on the second shaft within the chamber. The first gear is intermeshed with the second gear, and the first rotor is intermeshed with the second rotor, so as to transfer fluid from a suction port of the main case to the discharge port during rotation of the first and second shafts.

Claims

1. A pump, comprising: a main case having a chamber including a suction port and a discharge port; a faceplate assembly secured to a first side of the main case; a backplate assembly secured to a second side of the main case; a first shaft; a second shaft, wherein the first shaft and the second shaft are configured to extend through the chamber into bores of the faceplate assembly and bores of the backplate assembly; a first gear and a first rotor mounted for rotation on the first shaft within the chamber; and a second gear and a second rotor mounted for rotation on the second shaft within the chamber, wherein the first gear is intermeshed with the second gear and is configured to transfer fluid from the suction port to the discharge port during rotation of the first shaft and the second shaft, and wherein the first rotor is intermeshed with the second rotor and is configured to transfer fluid from the suction port to the discharge port during rotation of the first shaft and the second shaft.

2. The pump of claim 1, wherein the first gear and the first rotor together extend axially for a distance approximately equal to a width of the chamber, and wherein the second gear and the second rotor together extend axially for a distance approximately equal to the width of the chamber.

3. The pump of claim 1, wherein the first shaft simultaneously drives rotation of the first gear and the first rotor, and wherein the first gear drives rotation of the second gear, the second shaft, and the second rotor.

4. The pump of claim 1, wherein the fluid serves as a lubricant for the first gear and the second gear.

5. The pump of claim 1, further comprising: a third rotor mounted for rotation on the first shaft within the chamber; and a fourth rotor mounted for rotation on the second shaft within the chamber, wherein the first gear, the first rotor, and the third rotor together extend axially for a distance approximately equal to a width of the chamber, and wherein the second gear, the second rotor, and the fourth rotor together extend axially for a distance approximately equal to the width of the chamber.

6. The pump of claim 1, wherein the first gear and the first rotor are oriented to provide a continuous seal across a width of the chamber throughout a complete rotation of the first shaft.

7. The pump of claim 1, wherein the first rotor includes an elastomeric coating on a circumference of the first rotor.

8. The pump of claim 1, wherein the first rotor includes multiple lobes, wherein a support roller is installed at an end of each of the multiple lobes, and wherein each of the support rollers is configured to contact a curved wall of the chamber.

9. An assembly for a gear pump, comprising: a first gear and a first rotor mounted for rotation on a first shaft; and a second gear and a second rotor mounted for rotation on a second shaft, wherein the first shaft and the second shaft are configured to extend through a gear chamber of the gear pump with the first gear, the first rotor, the second gear, and the second rotor contained in the gear chamber, wherein, when installed in the gear chamber, the first gear is configured to intermesh with the second gear, and wherein, when installed in the gear chamber, the first rotor is configured to intermesh with the second rotor.

10. The assembly of claim 9, wherein the first gear and the first rotor together are configured to extend axially along the first shaft for a distance approximately equal to a width of the gear chamber.

11. The assembly of claim 10, wherein the first gear extends axially along the first shaft for a distance of more than half the width of the gear chamber.

12. The assembly of claim 9, wherein the first gear and the second gear are identical parts, wherein the first rotor and the second rotor are identical parts, wherein the first shaft includes a first rotor key seat and a first gear key seat positioned in a first angular orientation relative to each other, and wherein the second shaft includes a second rotor key seat and a second gear key seat positioned in a second angular orientation, relative to each other, that is different than the first angular orientation.

13. The assembly of claim 9, wherein the first gear is configured to drive rotation of the second gear, the second shaft, and the second rotor.

14. The assembly of claim 9, further comprising: a third rotor mounted for rotation on the first shaft; and a fourth rotor mounted for rotation on the second shaft, wherein the first gear, the first rotor, and the third rotor together are configured to extend axially for a distance approximately equal to a width of the gear chamber, and wherein the second gear, the second rotor, and the fourth rotor together are configured to extend axially for a distance approximately equal to the width of the gear chamber.

15. An assembly for a gear pump, comprising: a first gear and a first rotor mounted for rotation on a first shaft; a second gear and a second rotor mounted for rotation on a second shaft; and a case extension including an extended gear housing that is configured to align with a gear chamber of a main case of the gear pump to form a combined chamber, wherein the first shaft and the second shaft are configured to extend through the combined chamber with the first gear, the first rotor, the second gear, and the second rotor contained in the combined chamber, wherein, when installed in the combined chamber, the first gear is configured to intermesh with the second gear, and wherein, when installed in the combined chamber, the first rotor is configured to intermesh with the second rotor.

16. The assembly of claim 15, further comprising: a plate positioned between the first gear and the first rotor and between the second gear and the second rotor, wherein the plate includes a set of holes through which the first shaft and the second shaft pass.

17. The assembly of claim 15, wherein first shaft includes a drive end, and wherein the first rotor is located between the first gear and the drive end.

18. A method for reconfiguring a volumetric displacement capacity of a gear pump, the method comprising: disconnecting a faceplate assembly from a case of the gear pump; removing a shaft and gear set from a gear chamber of the case; inserting a replacement assembly into the gear chamber of the case, wherein the replacement assembly includes: a first gear and a first rotor mounted for rotation on a first shaft, and a second gear and a second rotor mounted for rotation on a second shaft; placing the faceplate assembly onto the first shaft and the second shaft and against the case; and securing the faceplate assembly to the case.

19. The method of claim 18, wherein inserting the replacement assembly into the gear chamber includes: intermeshing the first gear with the second gear in the gear chamber, and intermeshing the first rotor with the second rotor in the gear chamber.

20. The method of claim 18, wherein inserting the replacement assembly into the gear chamber includes: inserting an end of the first shaft, of the replacement assembly, into a bore in a backplate of the gear pump, wherein the first shaft includes the first rotor and the first gear keyed to the first shaft, and inserting an end of the second shaft, of the replacement assembly, into another bore in the backplate of the gear pump, wherein the second shaft includes the second rotor and the second gear keyed to the second shaft.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0004] FIG. 1 is a side view of a pump according to implementations described herein;

[0005] FIG. 2 is a side view of a hybrid gear and rotor assembly of the pump illustrated in FIG. 1;

[0006] FIG. 3A is a side perspective view of the hybrid assembly of FIG. 2;

[0007] FIG. 3B is an end view of the hybrid assembly of FIG. 2;

[0008] FIG. 4 is a side cross-sectional view of a pump with a hybrid assembly installed, according to an implementation;

[0009] FIG. 5 is an assembly view of a pump with a hybrid assembly, according to another implementation;

[0010] FIGS. 6A and 6B are side and perspective views, respectively, of a pump according to another implementation described herein;

[0011] FIGS. 7A and 7B are side and perspective views, respectively, of a portion of a hybrid assembly according to another implementation;

[0012] FIG. 7C is a front end view of a case extension of the hybrid assembly of FIG. 7A;

[0013] FIG. 8 is a side cross-sectional view of a pump with a hybrid assembly installed, according to another implementation;

[0014] FIG. 9 is an assembly view of a pump with a hybrid assembly, according to another implementation;

[0015] FIGS. 10A and 10B are front and rear perspective views of a hybrid assembly including a wear plate, according to another implementation;

[0016] FIG. 11 shows separate end views of a spur gear and rotor for a hybrid assembly for a pump, according to an implementation;

[0017] FIG. 12 shows separate end views of another spur gear and rotor for another hybrid assembly for a gear pump, according to another implementation;

[0018] FIGS. 13A and 13B are an end view and a partial cutaway perspective view, respectively, of another hybrid assembly within a housing, according to an implementation;

[0019] FIGS. 14A and 14B are an end view and a partial cutaway perspective view, respectively, of still another hybrid assembly within a housing, according to an implementation;

[0020] FIG. 15 is an end view of a hybrid assembly for a pump including rollers for a rotor section;

[0021] FIG. 16 is an end view of a hybrid assembly for a pump including coatings for a rotor section;

[0022] FIG. 17A is a perspective view of a portion of a hybrid assembly, according to another implementation;

[0023] FIG. 17B is a perspective view of portions of a drive shaft and idler shaft for the hybrid assembly of FIG. 17A;

[0024] FIG. 18 is a side cross-sectional view of a gear pump that can be converted to a hybrid gear and rotor pump, according to an implementation; and

[0025] FIGS. 19 and 20 are flow diagrams of a process for adding a hybrid assembly to a gear pump, according to an implementation described herein.

DETAILED DESCRIPTION

[0026] The following detailed description refers to the accompanying drawings. The same reference numbers in different drawings may identify the same or similar elements. Also, the following detailed description does not limit the invention.

[0027] Systems and methods described herein provide an external gear-and-rotor hybrid pump. The hybrid pump uses the gears of an external gear pump to drive rotors contained within the same flow volume. The gears of an external gear pump facilitate power transfer between a drive shaft and an idler shaft, while the rotors on each shaft are used for additional fluid transfer. This arrangement creates a rotary positive-displacement pump where the fluid is driven partially by rotors and partially by gears. The external gear-and-rotor hybrid pump may be assembled as original equipment or provided as a retrofit kit, such as for converting a conventional gear pump to an external gear-and-rotor hybrid pump.

[0028] Generally, rotors have a higher volumetric displacement capacity than gears and facilitate slower, gentler handling of fluids. According to an implementation, a pump may include, within a gear chamber, a hybrid gear-and-rotor assembly (also referred to herein as a hybrid assembly or a replacement assembly) that provides increased pump capacity and allows for smoother fluid transfer over a conventional gear pump. In another implementation, a hybrid assembly is provided as a retrofit kit to allow users to convert an existing external gear pump into a gear-and-rotor hybrid pump. Rotors of the hybrid assembly may also be provided with custom options that are typically not available with gears, since gear modifications are more limited by spacing and functional requirements. For example, rotor lobe customizations may include additions such as an elastomer lining, integrated support rollers, special coatings, etc., that may not be feasible with gears.

[0029] According to implementations described herein, shafts for the hybrid pump may be supported on both sides of the gear-and-rotor-hybrid fluid transfer components by journal bearings, needle bearings, or any other type of bearing. This type of support allows for higher pressure capabilities and less wear on the bearings than traditional lobe pumps with cantilever (or overhung) arrangements. In other implementations, the addition of integrated support rollers into the tips of the rotor lobes may result in further pressure capabilities and reduced wear. The addition of special coatings or rubber lining may further expand the scope of possible applications for using the pumps.

[0030] Traditional rotor pumps require a timing gear transmission to drive the rotors synchronously, since the rotor geometry does not facilitate power transfer. Furthermore, it is often preferable that the rotor lobes do not make physical contact for sanitary applications. In contrast with the hybrid pump described herein, traditional rotor pumps isolate the timing gears from the rotors. In traditional rotor pumps, the seals between the timing gear compartment and the flow volume add to the complexity of the pump and to the number of potential failure modes. The precise timing gears and seals also add to the cost and maintenance of the rotor pump. The traditional rotor pumps are also typically supported by bearings on only one side to withstand the forces exerted by the fluid discharge pressure. This overhung load not only limits the pressure capabilities of the pump, but also exacerbates the wear on the bearings supporting the overhung load.

[0031] Systems and methods described herein provide a hybrid pump that provides increased flow rates over conventional gear pumps while continuing to effectively handle heavy, viscous materials such as asphalt, roofing compounds, mastics, and molasses. According to an implementation, a pump includes a main case, a faceplate assembly, a backplate assembly, and a hybrid gear-and-rotor assembly. The main case includes a chamber having a suction port and a discharge port. The hybrid gear-and-rotor assembly includes a first (e.g., drive) shaft and a second (e.g., idle) shaft. The first shaft and the second shaft are configured to extend through the chamber into bores of the faceplate assembly and bores of the backplate assembly. The first shaft includes a first gear and a first rotor mounted for rotation on the first shaft within the chamber. The second shaft includes a second gear and a second rotor mounted for rotation on the second shaft within the chamber. The first gear is intermeshed with the second gear so as to transfer fluid from the suction port to the discharge port during rotation of the first shaft and the second shaft. The first rotor is intermeshed with the second rotor so as to transfer fluid from the suction port to the discharge port during rotation of the first shaft and the second shaft.

[0032] According to another implementation, a hybrid assembly may be provided for retrofit on a gear pump. The hybrid assembly may include a first gear and a first rotor, mounted for rotation on a first shaft, and a second gear and a second rotor, mounted for rotation on a second shaft. The first shaft and the second shaft are configured to extend through a gear chamber of a gear pump with the first gear, the first rotor, the second gear, and the second rotor contained in the gear chamber. When the hybrid assembly is installed in the gear chamber, the first gear is configured to intermesh with the second gear and the first rotor is configured to intermesh with the second rotor.

[0033] According to another implementation, a hybrid assembly may include a first gear and a first rotor mounted for rotation on a first shaft, a second gear and a second rotor mounted for rotation on a second shaft, and a case extension including an extended gear housing that is configured to align with a gear chamber of a main case of the gear pump to form a combined chamber. The first shaft and the second shaft may be configured to extend through the combined chamber with the first gear, the first rotor, the second gear, and the second rotor contained in the combined chamber. When installed in the combined chamber, the first gear may be configured to intermesh with the second gear, and the first rotor may be configured to intermesh with the second rotor.

[0034] The hybrid assembly may be provided as a kit that allows end users to change/increase the capacity of a pump without having to change hookup locations for the pump, and also provide users with the option to return the pump to the original flow rate if needed for a particular application. The hybrid assembly kit may allow users/customers to adjust the volumetric displacement of an existing system while maintaining the same connection points. In some implementations, a timing gear case extension and extended length bolts may be included with the hybrid assembly kit. Different size kits may be provided for different pumps and pump families to give users/customers options for their volumetric displacement without changing entire systems. Other advantages, characteristics and details will emerge from the description provided below with reference to the attached drawings and examples. However, the present invention is not limited thereto.

[0035] Exemplary embodiments for a pump 100 with a modular hybrid gear-and-rotor assembly 200 are described with reference to FIGS. 1-5. FIG. 1 is a side view of pump 100, while FIGS. 2-3B provide various views of a hybrid gear-and-rotor assembly 200 that may be used with pump 100. FIG. 4 is a side cross-sectional view of pump 100 with a hybrid assembly installed. FIG. 5 is an assembly view of another version of pump 100 with a hybrid assembly, according to another implementation. As shown in FIG. 1, pump 100 may include a faceplate assembly 110, a main case 120, and a backplate assembly 130. As described further herein, pump 100 may be equipped with hybrid assembly 200, shown in FIG. 2.

[0036] Referring collectively to FIGS. 1-5, main case 120 includes a gear chamber 122 with apertures in fluid communication with a suction port 124 and a discharge port 126. Main case 120 may include a front surface 125 and a rear surface 127 (see FIG. 4) to which faceplate assembly 110 and backplate assembly 130, respectively, may attach. Main case 120 may be formed (e.g., cast, machined, etc.) as a single piece or may be formed by joining multiple body sections to form gear chamber 122. Suction port 124 and discharge port 126 are not limited by their size or shape, and their locations may be generally on opposite sides of gear chamber 122 or in perpendicular planes (as shown in FIG. 1) somewhere between front surface 125 and rear surface 127. Spaced apertures in gear chamber 122 register with suction port 124 and a discharge port 126, with the suction port 124 being open to an inlet passage of pump 100, and the discharge port 126 being open to an outlet passage of pump 100.

[0037] Main casing 120 may be configured to contain a portion of hybrid assembly 200 in gear chamber 122. Hybrid assembly 200 may include a set of rotors 232 and 234, a set of gears 242 and 244, and corresponding set of shafts 252 and 254. Rotor 232 and gear 242 are mounted for rotation about a drive shaft or axle 252 at its center. Rotor 234 and gear 244 are similarly mounted for rotation about an idler shaft 254. Shafts 252 and 254 may each extend through chamber 122 in parallel. Shaft 252 and shaft 254 may be supported on opposite ends by faceplate assembly 110 and backplate assembly 130. The drive shaft 252 may include a drive end 253 that extends through backplate assembly for coupling to a driver (e.g., a motor) for pump 100 via a key mechanism 260, for example. Shaft 252 and shaft 254 may each be made of the same material, such as steel or another rigid material.

[0038] Gears 242 and 244 may have peripheral teeth that intermesh so that the rotation of one of the gears causes rotation of the other gear. Thus, the rotation of one of the gears (e.g., gear 242) by drive shaft 252 causes rotation of the other gear (e.g., gear 244) about shaft 254. The teeth of gears 242 and 244 may have uniform sizes and may be machined to intermesh for all angular positions in a rotation of the gears 242, 244. Gears 242 and 244 may have helically oriented teeth (as illustrated herein), herringbone gear teeth, or straight spur teeth, although implementations are not limited to these shapes. Gears 242 and 244 may be formed of a material such as cast iron, steel, ceramic, plastic, etc. Gears 242 and 244 may be formed to provide a profile with a radius of curvature nearly equal to the radius of curvature of rounded wall sections within portions of gear chamber 122.

[0039] Rotors 232 and 234 may perform similarly to rotors in a rotary lobe pump. Rotor 232 may be fixed on shaft 252 adjacent to gear 242. Similarly, rotor 234 may be fixed on shaft 254 adjacent to gear 244. In one implementation, keyways 262/264 may be provided for key mechanisms 260 to secure rotors 232/234 in place. Rotor 232 may be driven directly by shaft 252. Thus, shaft 252 (e.g., when attached to a motor) simultaneously drives rotation of gear 242 and rotor 232. Rotor 234 may be driven by shaft 254, which is driven by gears 242 and 244. The lobes of rotors 232 and 234 may intermesh but are configured not to contact each other.

[0040] The axial length of gears 242 and 244 may extend partly across the width (W) of chamber 122, as shown in FIG. 4, with lobed rotors 232 and 234 extending along the rest of the width of chamber 122. Thus, gear 242 or 244 and rotor 232 or 234 together extend axially for a distance equal to the width of the chamber. The axial length of gears 242 and 244 may be the same, and the axial length of lobed rotors 232 and 234 may also be the same. The combined axial length of rotor 232 and gear 242 may span the width of chamber 122, and the combined axial length of rotor 234 and gear 244 may also span the width of chamber 122. The axial length of rotors 232/234 may be the same or different than gears 242/244. That is, in some implementations, rotors 232 and 234 may span more than half the width of chamber 122, and in other implementations, gears 242 and 244 may span more than half the width of chamber 122. Generally, longer axial length of gears 242/244 supports higher pressure ratings for pump 100, while a longer axial length of rotors 232/234 provide greater fluid transfer capacity.

[0041] Using hybrid assembly 200, pump 100 may drive fluid partially by rotors 232/234 and partially by gears 242/244. Gears 242/244 also serve as timing gears for rotors 232/234. In one implementation, both rotors 232/234 and gears 242/244 may be formed to provide a profile with a radius of curvature nearly equal to the radius of curvature of rounded wall sections within portions of chamber 122. That is, rotors 232/234 and gears 242/244 may have the same or similar major diameters.

[0042] During operation, fluid is drawn from suction port 124 into chamber 122. Particularly, rotors 232 and 234 intermesh during rotation, such that cavities between lobes of rotors 232 and 234 expand near the suction port 124 to draw fluid into chamber 122. The fluid (e.g., process fluid pumped through chamber 122) may serve as a lubricant for gears 242/244. Gears 242 and 244 also intermesh during rotation to similarly draw in fluid near suction port 124. As described further herein, rotors 232 and 234 may be synchronized by keyway alignment with gears 242 and 244. In contrast with traditional rotary lobe or circumferential piston pumps, where at least one of the rotors is fixed using a ring fetter or other complex method, implementations described herein may synchronize rotors 232 and 234 using keyways on both shaft 252 and 254. In the example of FIG. 3B, keyways on the upper shaft 252 are offset by 90 degrees while the keyways on the lower shaft 254 are in-line. Depending on the number of gear teeth and rotors, a different offset may be required to use like gears and like rotors. An advantage of using the offset keyways is a reduction of unique parts. Keyway alignment is described further below, for example, in connection with FIGS. 17A and 17B.

[0043] As rotors 232/234 and gears 242/244 rotate, fluid is trapped in cavities between the lobes/teeth and the curved wall sections 123 (FIG. 5) of chamber 122. As described further herein, each rotor/gear combination (e.g., rotor 232/gear 242 and rotor 234/gear 244) is aligned or otherwise configured to provide a continuous seal along the width of chamber 122 to prevent slippage. As shown, for example, in FIG. 3A, a continuous seal line 302 may be formed along a tooth of gear 242 and a lobe of rotor 232 that would contact (or nearly contact) a curved wall section 123 of chamber 122 during rotation of gear 242 and rotor 232. Another continuous seal line (not shown) may be formed along the opposite lobe of rotor 232 and tooth of gear 242, such that a continuous seal is provided across a width (W.sub.1) of chamber 122 throughout a complete rotation of shaft 252. Rotor 234 and gear 244 may be similarly situated on shaft 254 to also provide a continuous seal is provided across a width of chamber 122 throughout a complete rotation of shaft 254. Thus, the fluid is transported to the discharge side, where intermeshing of the rotors or gears compresses the respective cavities and forces fluid out through the discharge port 126. The larger cavities of rotors 232/234, relative to cavities of gears 242/244, allows for increased volume and gentler (e.g., less turbulent) transport of fluids than would be possible with a single gear set.

[0044] As shown in FIGS. 1 and 4, for example, faceplate assembly 110 may include a structure to close off one side of main case 120, at front surface 125, while supporting drive shaft 252 and idler shaft 254. In one implementation, faceplate assembly 110 may include a bore 112 with a bearing 113 to support drive shaft 252. Faceplate assembly 110 may also include bore 114 with a bearing 115 to support idler shaft 254. Gear chamber 122 may be closed on its front side by faceplate assembly 110 with a fluid-tight seal. For example, faceplate assembly 110 may include a set of bolt holes 118 (FIG. 5) near the periphery of faceplate assembly 110 and extending longitudinally (e.g., substantially parallel to bores 112 and 114) through faceplate assembly 110. Main case 120 may include a set of threaded connection holes 128 opening at the front surface 125 and extending at least partially into main case 120 from front surface 125 toward the rear surface 127. Bolts 162, inserted through the bolt holes 118 into connection holes 128, connect faceplate assembly 110 to main case 120 and align bores 112 and 114 for receiving shafts 252 and 254, respectively.

[0045] The number and/or arrangement of holes 118/128 may vary depending on the size and/or configuration of pump 100. In any configuration, the number of bolts holes 118 and connection holes 128 may be the same, such that the set of bolt holes 118 in faceplate assembly 110 is configured to align with the set of connection holes 128 in main case 120. As shown, for example, in the configuration of FIG. 5, faceplate assembly 110 and main case 120 may each include sixteen (16) holes 118/128 and two (2) index holes 119/129 (also referred to as alignment holes). Index holes 119/129 may be used to align main case 120 with faceplate assembly 110. Index holes 119/129 may be configured to receive alignment pins 164. Index holes 119/129 may have, for example, a smaller diameter bore and/or smaller tolerances than holes 118/128 for precise alignment.

[0046] In one implementation, main case 120 and faceplate assembly 110 may be bolted together and sealed using a compressible gasket 170 therebetween. Gasket 170 provides a resilient compressible material at the interface between main case 120 (e.g., front surface 125) and faceplate assembly 110. Gasket 170 may include a continuous substantially elliptical body that includes an interior opening 172 generally conforming to the cross-sectional shape of chamber 122 with holes 173 in a pattern corresponding to connection holes 128. Gasket 170 may be constructed of any suitably durable and elastomeric material, such as silicone, butyl rubber polyamide, polyester, olefin, styrenics, urethane, or a composite of a thermoplastic and cured rubber. More specific examples include room temperature vulcanization silicone, uncured ethylene-propylene-diene-monomer (EPDM) blended with polypropylene, styrene-butadiene-styrene block polymer, styrene-ethylene-butylene-styrene block polymer, cured ethylene-propylene-diene copolymer/polypropylene blend, cured isobutylene isoprene rubber/polypropylene blend, and cured nitrile butadiene rubber/polyvinylchloride blend. When gasket 170 is mated between main case 120 and faceplate assembly 110, gasket 170 forms a fluid-tight seal between the connected surfaces, preventing fluid leakage from pump 100. In another implementation, a fluid-tight seal may be achieved when a washer, copper layer, liner, or sealant (e.g., a curable liquid or spray) is inserted between main case 120 and faceplate assembly 110 when joined together.

[0047] Similar to faceplate assembly 110, backplate assembly 130 may include a structure to close off another side of main case 120, at rear surface 127, while supporting drive shaft 252 and idler shaft 254. In one implementation, backplate assembly 130 may include a bore 132 with a bearing 133 to support drive shaft 252. Backplate assembly 130 may also include a bore 134 with a bearing 135 to support idler shaft 254. Gear chamber 122 may be closed on its rear side by backplate assembly 130 with a fluid-tight seal. For example, backplate assembly 130 may include a set of bolt holes 138 near the periphery of backplate assembly 130 and extending longitudinally (e.g., substantially parallel to bores 132 and 134) through backplate assembly 130. Main case 120 may include a set of connection holes 128 opening at the rear surface 127 and extending at least partially into main case 120 from rear surface 127 toward the front surface 125. Bolts 162, inserted through the bolt holes 138 into connection holes (not shown), connect backplate assembly 130 to main case 120 align bores 132 and 134 for receiving shafts 252 and 254, respectively. In one implementation, main case 120 and backplate assembly 130 may be bolted together and sealed using a compressible gasket 170 (not shown) therebetween.

[0048] FIGS. 1-5 illustrate an example arrangement of hybrid assembly 200. In other implementations, a different arrangement of gears and rotors may be used. For example, in another implementation of hybrid arrangement 200, a single gear 242 may be mounded on shaft 252 with rotors 232 mounted on either end of gear 242. The axial length of gear 242 may be approximately equal to the total axial length of both rotors 232, although other axial length ratios may be used. Rotors 234 and gears 244 may be similarly situated on shaft 254. Rotors 232/234 and gears 242/244 installed on shafts 252/254 may be configured to be contained within chamber 122 of main case 120. In still another implementation of hybrid arrangement 200, a single rotor 232 may be mounted on shaft 252 with gears 242 mounted adjacent to either end of rotor 232, with a similar arrangement of rotors 234 and gears 244 on shaft 254. In other implementations, more than two gears or rotors may be included on a single shaft.

[0049] FIGS. 6A-9 illustrate another embodiment of pump 100 with a modular hybrid gear-and-rotor assembly 700. FIGS. 6A and 6B are side and perspective views, respectively, of pump 100 according to another implementation. FIGS. 7A and 7B are side and perspective views, respectively, of a portion of hybrid assembly 700 that may be used with pump 100 and shown with journal bearings included. FIG. 7C is front end view (i.e., from faceplate assembly 110) of a timing gear case extension 710 for hybrid gear-and-rotor assembly 700. FIG. 8 is a side cross-sectional view of pump 100 with hybrid assembly 700 installed. FIG. 9 is an assembly view of another version of pump 100 with hybrid assembly 700 installed, according to an implementation. Referring collectively to FIGS. 6A-9, pump 100 may include a faceplate assembly 110, a main case 120, and a backplate assembly 130. As described further herein, pump 100 may be equipped with hybrid assembly 700, including optional timing gear case extension 710.

[0050] Pump 100 may be consistent with descriptions provided above in connection with FIG. 1. For example, pump 100 may include a faceplate assembly 110, a main case 120, and a backplate assembly 130. Main case 120 may include gear chamber 122 with apertures in fluid communication with a suction port 124 and a discharge port 126. In the example of FIGS. 6A and 6B, suction port 124 and discharge port 126 are oriented on opposite sides of gear chamber 122 between front surface 125 and rear surface 127. Main casing 120 may contain a portion of hybrid assembly 700 in gear chamber 122.

[0051] According to implementations described herein, increased volume displacement capacity for pump 100 may be achieved by adding case extension 710. Thus, in one implementation, hybrid assembly 700 may include case extension 710, a set of elongated rotors 232/234, a set of gears 242/244, and corresponding elongated shafts 252 and 254. In some implementations, hybrid assembly 700 may be provided with a kit that also includes one or more additional gaskets 170, a set of elongated bolts 962 and elongated alignment pins 964 to facilitate installation, as described further herein.

[0052] As shown in FIGS. 6A, 6B, 8, and 9, timing gear case extension 710 is attached on the front side of gear chamber 122 (e.g., at surface 125) between main casing 120 and faceplate assembly 110. Timing gear case extension 710 may include an extended gear housing 712 and bores 714 that are configured to align with bores 112 and 114 of faceplate assembly 110. Timing gear case extension 710 may form a combined chamber 122/712 that accommodates elongated shafts 252/254, elongated rotors 232/234, and gears 242/244 of hybrid assembly 700. Bores 714 of extended gear housing 712 may be configured to hold additional journal bearings 715 to support shafts 252/254. Case extension 710 may not include an inlet port or outlet port for pumped fluid. Elongated shafts 252 and 254 may extend through combined chamber 122/712 and be supported by respective bearings 113 and 115 in faceplate assembly 110, bearings 133 and 135 in backplate assembly 130, and bearings 715 in case extension 710.

[0053] Similar to main case 120, case extension 710 may be formed (e.g., cast, machined, etc.) as a single piece or may be formed by joining multiple body sections. Faceplate assembly 110, main case 120, backplate assembly 130, and case extension 710 may be formed from the same material, such as cast iron, to provide consistent material properties. Case extension 710 may have a thickness, T (FIG. 8), in the axial direction. Thickness, T, may add to the overall width W.sub.1 of main case 120 to form a new width W2. Thus, when used with case extension 710, the entire width W.sub.1 of chamber 122 may be utilized for rotors 232/234.

[0054] In contrast with the orientation shown in FIGS. 1-5, for hybrid assembly 700 gears 242/244 may not be mounted on shafts 252/254 closer to backplate 130 (i.e., the drive end 253) of pump 100. Instead, gears 242/244 may be mounted axially closer to faceplate assembly 110 in hybrid assembly 700. For example, gear 242 is mounted on shafts 252 with rotors 232 in between the drive end 253 and gear 242. The arrangement of gears 242/244 and rotors 232/234 in hybrid assembly 700 allows for easier access, inspection, and maintenance of gears 242 when installed in combined chamber 122/712. More particularly, gears 242/244 may be accessed by removing faceplate assembly 110 from case extension 710 and/or main case 120.

[0055] When hybrid assembly 700 is installed in combined chamber 122/712, gears 242 and 244 may intermesh and cause rotation of rotors 232 and 234 as described above in connection with FIGS. 1-5. In the example of FIGS. 7A and 7B, rotors 232/234 may be circumferential-piston-style rotors, also referred to as claw-type rotors. The circumferential-piston-style rotors may be operated in a similar manner to the bi-lobe rotors described above (e.g., FIGS. 3A and 3B). That is, rotors 232/234 may be mounted on shafts 252/254 and configured so that rotors 232/234 do not contact each other when the rotors 232/234 rotate within chamber 122. In other implementations, bi-lobe, tri-lobe or other lobe rotor shapes may be used in hybrid assembly 700.

[0056] In another implementation, hybrid assembly 700 may include a wear plate 720, also referred to as a divider plate. Plate 720 may be inserted between the respective rotor/gear set on each of shaft 252 and 254. According to one implementation, plate 720 may have a substantially elliptical perimeter that generally matches the exterior cross-sectional perimeter of chamber 122. Plate 720 may include bolt holes 728 and alignment holes 729 in a pattern corresponding to holes in main case 120 (e.g., connection holes 128, index holes 129) and holes in faceplate assembly 110 (e.g., bolt holes 118, index holes 119).

[0057] When plate 720 is mated between main case 120 and case extension 710, plate 720 may form a fluid-tight seal between the connected perimeter surfaces, preventing fluid leakage from pump 100. In another implementation, one or more gaskets (e.g., gasket 170) may be used for a seal. Plate 720 may include holes for shafts 252 and 254 to pass through (e.g., holes, not visible, that align with bores 714 of case extension 710). Plate 720 does not rotate within chamber 122.

[0058] Plate 720 may isolate rotors 232/234 from gears 242/244 and may serve to prevent fluid slippage from the rotor cavities to the gear cavities in chamber 122. For example, plate 720 may be a solid plate (e.g., bronze or another metal). However, in one implementation, clearances between journal bearings 715 and shafts 252/254 may permit some process fluid to enter extended gear housing 712 and provide lubrication for gears 242/244. According to another implementation, a set of seals 802 (FIG. 8) may be provided at the interface of shafts 252/254 and plate 720 to hermetically seal off gears 242/244 in extended gear housing 712 from fluid in chamber 122. If seals 802 are used, oil or grease may be provided separately in extended gear housing 712 to act as a lubricant/coolant for gears 242/244.

[0059] In one implementation, case extension 710 may include a set of bolt holes 718 and alignment holes 719 around the periphery of case extension 310 and extending longitudinally through case extension 710. The pattern of holes 718/719 may match the pattern of holes 118/119 and holes 128/129 used for faceplate assembly 110 and main case 120, respectively. Elongated alignment pins 964 may be inserted through alignment holes 119 of faceplate assembly 110 and alignment holes 719 of case extension 710 and into alignment holes 129 of main case 120 to align faceplate assembly 110 and case extension 710 to main case 120. Similarly, elongated bolts 962 may be inserted through the bolt holes 118 and bolt holes 318 into connection holes 128 to secure the components together. The overall length of elongated bolts 962 and elongated alignment pins 964 may generally exceed the length of bolts 162 and alignment pins 164 by thickness T of case extension 710.

[0060] FIGS. 10A and 10B are front and rear perspective views of hybrid assembly 200 including a divider plate 1010, according to another implementation. As shown in FIGS. 10A and 10B, according to another implementation, wear plate 720 may be replaced with divider plate 1010 that may have a perimeter that substantially matches the interior cross-section of chamber 122. Plate 1010 may be used, for example, when gears 242/244 and rotors 232/234 both fit within the width, W.sub.1 (FIG. 4), of chamber 122 (e.g., no case extension 710 is used). Like plate 720, plate 1010 may include holes for shafts 252 and 254. In one implementation, plate 1010 may be a continuous or solid plate. In another implementation, where rotor/gear pairs (e.g., rotor 232/gear 242 and rotor 234/gear 244) are aligned to form continuous seal lines 302, plate 1010 may be a semi-permeable material, such as a mesh screen, or include perforations to permit lubrication from process fluids while preventing large solids from becoming trapped between gears 242/244.

[0061] FIGS. 11 and 12 illustrate examples of some different gear-and-rotor combinations for hybrid assembly 200, in accordance with other implementations. Rotors 232/234 may be configured with a variety of different shapes and/or sizes for different applications, such as different numbers of lobes and/or different lobe shapes. For example, rotors 232/234 may be configured as lobed rotors, circumferential pistons, or other shapes that move fluids.

[0062] Referring collectively to FIGS. 11 and 12, gears 242/244 are sized with an outer diameter so that teeth 1102 rotate close to the curved walls 123 of chamber 122 (e.g., FIG. 5). Rotors 232/234 are configured to have matching pitch diameter (PD) and outer diameter (OD) to gears 242/244. Thus, the number of lobes 1104 in rotor 232/234 may vary depending on the gear 242/244 selected for a particular pump application. In the example of FIG. 11, a gear 242/244 with twelve teeth 1102 and a given pitch diameter PD may require a rotor 232/234 with five lobes 1104. In the example of FIG. 12, a gear 242/244 with six teeth 1102 and a given pitch diameter PD may require a rotor 232/234 with two lobes 1104.

[0063] According to one implementation, the orientation of rotor 232 and gear 242 on shaft 252 will provide at least one continuous seal line at any degree of rotation throughout a complete rotation of shaft 252. For example, rotor 232 and gear 242 may be aligned to form a continuous seal line 1732 (e.g., shown as line 302 of FIG. 3A) where an end of lobe 604 on rotor 232 and a tip of tooth 1102 on gear 242 form a seal against curved wall sections 123 of chamber 122. When the seal line 302 rotates out of contact with curved wall section 123, another seal line may be rotate into contact with wall section 123. Rotor 234 and gear 244 on shaft 254 may be similarly oriented to provide a continuous seal line. The continuous seal lines may prevent slippage from backpressure in chamber 122.

[0064] According to another implementation, other approaches besides use of plate 720 or 1010 may be used to close a fluid slip path in hybrid assembly 200. For example, FIGS. 13A and 13B are a partial cutaway end view and a partial cutaway perspective view, respectively, of another hybrid assembly 200 within main case 120. The hybrid assembly 200 of FIGS. 13A and 13B use rotors 232/234 with two lobes 1104 and spur gears 242/244 with ten teeth. FIGS. 14A and 14B are a partial cutaway end view and a partial cutaway perspective view, respectively, of another hybrid assembly 200 within main case 120 (shown without shafts 252 and 254). The hybrid assembly 200 of FIGS. 14A and 14B use rotors 232/234 with three lobes 1104 and spur gears 242/244 with ten teeth. As shown in FIGS. 13A-9B, different sizes of rotors 232/234 and gears 242/244 may be used, and main case 120 may be provided with a stepped chamber 1322. In such an implementation, rotor 232, for example, may have a larger outside diameter than gear 242. Stepped chamber 1322 may include a first (e.g., larger) curved wall section 1323 for rotor 232 and a second (e.g., smaller) curved wall section 1324 for gear 244. A shoulder 1325 formed between curved wall sections 1323 and 1324 may serve to prevent fluid slippage between the rotor cavities to the gear cavities.

[0065] FIGS. 15 and 16 illustrate customization options that be used with rotors 232/234 in accordance with exemplary implementations. As shown in FIG. 15, support rollers 1502 may be installed at the tip or end of each lobe 1104. Rollers 1502 may be configured to contact curved walls 123 of chamber 122 as rotors 232/234 rotate. Rollers 1502 may be configured to rotate along an axis that is parallel to the axis of shaft 252.

[0066] Rollers 1502 may extend radially beyond the tips of lobes 1104 to contact the portion of chamber 122 defined by the curved wall sections 123 during rotation of rotors 232/234. Rollers 1502 may provide additional support for rotors 232/234 and seal the fluid slip path (e.g., radial running clearance areas) that typically exist between the outer tip of lobes 1104 and the portion of chamber 122 defined by the curved wall sections 123. Rollers 1502 may be made from a rigid or semi-rigid material. In one implementation, rollers 1502 may be secured within slots or channels formed at the ends of lobes 1104. The slots may extend axially along the tip of lobe 1104 and into the rotor toward the respective axle or shaft.

[0067] As shown in FIG. 16, an elastomer coating 1604 may be added to rotors 232/234 in another implementation. Elastomer coating 1604 may be applied and cured, for example, on the circumference or outer surface of individual rotors 232/234 prior assembly and insertion of hybrid assembly 200. Elastomer coating 1604 may include for example, an elastically deformable material, such as rubber, with an even or smooth profile. According to one implementation, elastomer coating 1604 may be used to seal the fluid slip path that typically exist between the outer tip of lobes 1104 and the portion of chamber 122 defined by the curved wall sections 123.

[0068] FIG. 17A is a perspective view of a hybrid gear-and-rotor assembly 700, shown without wear plate 720 or divider plate 1010, according to an implementation. FIG. 17B is a perspective view showing key seats on a portion of shafts 252 and 254 for assembly 700. As shown in FIG. 17A, rotors 232/234 may include keyway 1732/1734 (which may correspond to keyways 262/264), and gears 242/244 may include keyways 1742/1744. As shown in FIG. 17B, drive shaft 252 may include key seats 1702 and 1704, while idle shaft 254 may include key seats 1712 and 1714. Key seats 1702, 1704, 1712, and 1714 may be configured to align a selected set of gears 242/244 and rotors 232/234.

[0069] Thus, rotors 232/234 and gears 242/244 may be identical for each assembly 700, while shafts 252 and 254 may have different key seat orientations to provide proper rotor/gear alignment. In the example of FIGS. 17A and 17B, gear 242 and gear 244 are identical parts, rotor 232 and rotor 234 are identical parts, shaft 252 includes rotor key seat 1704 and gear key seat 1702 positioned in one angular orientation (e.g., essentially in-line), and shaft 254 includes rotor key seat 1714 and gear key seat 1712 positioned in a different angular orientation (e.g., offset from each other). That is, key seats 1712 and 1714 on shaft 254 are offset by about 15 degrees from each other while the key seats 1702 and 1704 on shaft 252 are in-line.

[0070] To align rotors/gears of assembly 700 in a pump 100, shafts 252/254 may be inserted in chamber 122 (e.g., FIG. 6A), rotors 232/234 keyed to shafts 252/254 at keyways 1732 and 1734 (e.g., matched to key seats 1704 and 1714 with key mechanisms 260) may be roughly aligned to mesh within chamber 122. Gears 242/244 may then be keyed to shafts 252/254 at keyways 1742 and 1744 (e.g., matched to key seats 1702 and 1712 with key mechanisms 260). Generally, the number of teeth 1102 may be relatively few to prevent the possibility of both gears 242/244 and rotors 232/234 meshing without proper alignment. For example, in some implementations, each of gears 242/244 may include 8 to 14 teeth. Rotors 232/234 may thus be synchronized at installation by keyway alignment, without relying on a ring fetter or other more complex alignment methods. Furthermore, the use of keyway alignment can be used for alignment of rotors 232/234 and gears 242/244 regardless of the placement of rotors and gears relative to a drive end (e.g., the orientation of gears/rotors in FIG. 2 vs. FIG. 7A relative to drive end 253). That is, the order of insertion of rotors 232/234 and gears 242/244 described above may be reversed in other implementations.

[0071] While the offsets of FIGS. 17A and 17B are described in the context of key seats and keyways, in other implementations, pin joints, splined shafts or a combination of key seats and splines may be used to provide required offsets for rotors 232/234 and gears 242/244. Installation of hybrid assemblies 200/700 may be simplified by providing shafts that synchronize/align rotors and gears by a specific arrangement of keyways and/or splines.

[0072] FIG. 18 provides a side cross-sectional view of an external gear pump 1800 with conventional gears. According to another implementation described herein, hybrid assemblies 200 or 700 may be added to conventional gear pump 1800. For example, increased volume displacement capacity over a base configuration of pump 1800 may be achieved by replacing gears 1842/1844 and shafts 1852/1854 with hybrid assembly 200 or 700. According to an implementation, hybrid assembly 200 or 700 may be provided as a kit to reconfigure pump 1800.

[0073] Faceplate assembly 110, gears 1842/1844, and shafts 1852/1854 may be removed from pump 1800, so that rotors 232/234, gears 242/244, and shafts 252/254 of hybrid assembly 200 may be inserted into main case 120, with ends of shafts 252 and 254 positioned in bores 132 and 134, respectively. Faceplate assembly 110 (with gasket 170 and/or case extension 710) may then be mated to front surface 125 of main case 120, with shafts 252 and 254 positioned into bores 112 and 114, respectively.

[0074] FIG. 19 is a flow diagram of a process 1900 for converting a standard gear pump to a hybrid gear-rotor pump, according to an implementation described herein. Process 1900 may include disconnecting a faceplate assembly from the main case of a gear pump (block 1910) and removing a shaft and gear set from the main case (block 1920). For example, a technician may remove bolts 162 and alignment pins 164 from faceplate assembly 110 and remove faceplate assembly 110 from main case 120 of pump 1700. The technician may then remove the original shaft and gear set (e.g., gears 1742 and 1744, drive shaft 1752, and idler shaft 1754) from main case 120. In one implementation, the technician may also detach backplate assembly 130 from main case 120 to facilitate removal of the shaft and gear set.

[0075] Process 1900 may further include selecting a hybrid gear-and-rotor assembly (block 1930) and inserting a hybrid gear-and-rotor assembly into the gear chamber of the main case (block 1940). For example, a technician may select a hybrid assembly 200 (e.g., with rotors 232/234, gears 242/244, drive shaft 252, and idler shaft 254) or hybrid assembly 700 (e.g., with rotors 232/234, gears 242/244, drive shaft 252, idler shaft 254, and case extension 710) corresponding to the size of pump 100/chamber 122. In some implementations, different gear/rotor arrangements (e.g., as described above in connection with FIGS. 11A-12) may be available to provide a selected pressure and/or volumetric displacement rating for pump 100. Rotors 232/234 may be interleaved, gears 242/244 may be interleaved (e.g., teeth intermeshed), and the hybrid assembly 200 or 700 may be slid or inserted into chamber 122 of main case 120 with the ends of drive shaft 252 and idler shaft 254 extending into bores 132 and 134 of backplate assembly 130. In one implementation, the technician may detach backplate assembly 130 from main case 120 to facilitate insertion of drive shaft 252 and idler shaft 254 into bores 132 and 134 and then reconnect backplate assembly 130 to main case 120.

[0076] Process 1900 may also include applying the faceplate and optional case extension over the shafts of the hybrid gear-and-rotor assembly (block 1950) and securing the faceplate assembly and case extension to the main case (block 1960). For example, a technician may place case extension 710 over the exposed ends of shafts 252/254, if necessary, and insert ends of drive shaft 252 and idler shaft 254 may into bores 112 and 114 of faceplate assembly 110. Faceplate assembly 110 may be slid along shafts 252/254 until faceplate assembly 110 contacts case extension 710 or front surface 125 of main case 120. In one implementation, another gasket 170 may be inserted between faceplate assembly 110 and case extension 710/main case 120. Alignment pins 164 may be inserted through alignment holes 119 of faceplate assembly 110 into alignment holes 129 of main case 120 to align main case 120 and faceplate assembly 110. Bolts 162 may be inserted through the bolt holes 118 into connection holes 128 to secure the components together. Alternatively, elongated bolts 962 may be inserted through bolt holes 118 and holes 718 to secure faceplate assembly 110 and case extension 710 to main case 120.

[0077] In one implementation, process block 1940 may include steps shown in FIG. 20. As shown in FIG. 20, process block 1940 may include inserting a drive shaft with a keyed rotor (block 2010) and inserting an idler shaft with a keyed rotor and generally aligning the rotors to mesh (block 2020). For example, shafts 252/254 may be inserted in chamber 122. Rotors 232/234 keyed to shafts 252/254 at keyways 1732 and 1734 (e.g., matched to key seats 1704 and 1714) may be generally oriented to mesh within chamber 122.

[0078] Steps of process block 1940 may further include inserting a gear keyed on the drive shaft (block 2030) and inserting a gear keyed on the idler shaft and rotating the idler shaft to mesh the gears (block 2040). For example, gears 242/244 may then be keyed to shafts 252/254 at keyways 1742 and 1744 (e.g., matched to key seats 1702 and 1712). The configuration of key seats 1702/1712 and 11704/1714 may ensure proper meshing/orientation of gears 242/244 and rotors 232/234.

[0079] Installation of the hybrid assembly into a gear pump as described above may provide greater flow rates from the original/conventional gear pump. Using similar steps to those above, users have the option to re-install the original gear components and return the pump to the original flow rate and pressure ratings, if needed for a particular application.

[0080] Apparatuses and methods described herein provide a hybrid gear-and-rotor pump. A pump includes a faceplate assembly, a backplate assembly, a main case with a chamber, and a hybrid gear-and-rotor assembly. The hybrid gear-and-rotor assembly includes a first shaft and a second shaft. The first and second shafts are configured to extend through the chamber into bores in the faceplate and backplate assemblies. The first shaft includes a first gear and a first rotor mounted for rotation on the first shaft within the chamber. The second shaft includes a second gear and a second rotor mounted for rotation on the second shaft within the chamber. The first gear is intermeshed with the second gear, and the first rotor is intermeshed with the second rotor, so as to transfer fluid from a suction port of the main case to the discharge port during rotation of the first and second shafts.

[0081] The foregoing description of exemplary implementations provides illustration and description but is not intended to be exhaustive or to limit the embodiments described herein to the precise form disclosed. Modifications and variations are possible in light of the above teachings or may be acquired from practice of the embodiments. For example, while series of blocks have been described with regard to the processes illustrated in FIGS. 19-20, the order of the blocks may be modified according to other embodiments. Further, non-dependent blocks may be performed in parallel. Additionally, other processes described in this description may be modified and/or non-dependent operations may be performed in parallel.

[0082] Although the invention has been described in detail above, it is expressly understood that it will be apparent to persons skilled in the relevant art that the invention may be modified without departing from the spirit of the invention. Various changes of form, design, or arrangement may be made to the invention without departing from the spirit and scope of the invention. Therefore, the above-mentioned description is to be considered exemplary, rather than limiting, and the true scope of the invention is that defined in the following claims.

[0083] As set forth in this description and illustrated by the drawings, reference is made to an exemplary embodiment, an embodiment, embodiments, etc., which may include a particular feature, structure or characteristic in connection with an embodiment(s). However, the use of the phrase or term an embodiment, embodiments, etc., in various places in the specification does not necessarily refer to all embodiments described, nor does it necessarily refer to the same embodiment, nor are separate or alternative embodiments necessarily mutually exclusive of other embodiment(s). The same applies to the term implementation, implementations, etc.

[0084] The terms a, an, and the are intended to be interpreted to include one or more items. The term and/or is intended to be interpreted to include any and all combinations of one or more of the associated items. The word exemplary is used herein to mean serving as an example. Any embodiment or implementation described as exemplary is not necessarily to be construed as preferred or advantageous over other embodiments or implementations.

[0085] Use of ordinal terms such as first, second, third, etc., in the claims to modify a claim element does not by itself connote any priority, precedence, or order of one claim element over another, the temporal order in which acts of a method are performed, the temporal order in which instructions executed by a device are performed, etc., but are used merely as labels to distinguish one claim element having a certain name from another element having a same name (but for use of the ordinal term) to distinguish the claim elements.

[0086] No element, act, or instruction used in the description of the present application should be construed as critical or essential to the invention unless explicitly described as such.