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TRIGGER MECHANISM WITH DOUBLE SEAR
BACKGROUND OF THE INVENTION The present invention pertains generally to firearms and, in particular aspects, to a sear assembly for a firearm.To protect against an unintentional discharge of a firearm, firearm and trigger manufacturers have designed and implemented various safety mechanisms. There remains, however, a desire for new and improved safety mechanisms.
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SUMMARY OF THE INVENTION A sear assembly may include a primary sear including a primary sear body having a primary sear top edge. A sear catch may extend from the primary sear top edge and a top sloped surface may be positioned rearward of the sear top edge. A primary sear opening can be defined through the primary sear body. The sear assembly may also include a safety sear including a safety sear body having a safety sear rear surface. A safety sear opening may be defined through the safety sear body. A sear assembly pin may be insertable within the primary sear opening and the safety sear opening when the primary sear opening is aligned with the safety sear opening. The primary sear and the safety sear may each be independently rotatable about the sear assembly pin. In some embodiments, the primary sear and the safety sear each have a center of mass that is located at the center of rotation defined by the sear assembly pin.In some embodiments, the sear assembly may also include a sear lever that surrounds the sear assembly pin. Rotation of the sear lever about the sear assembly pin may cause rotation of the primary sear and the safety sear about the sear assembly pin. The sear assembly may also include a safety sear torsion spring designed to apply tension to the safety sear and a primary sear torsion spring designed to apply tension to the primary sear. In certain embodiments, the tension applied to the safety sear by the safety sear torsion spring is independent of the tension applied to the primary sear by the primary sear torsion spring.In some embodiments, the safety sear includes a safety sear flange that extends laterally from the safety sear body, and the primary sear includes a primary sear depression defined in the primary sear top edge. The safety scar flange may fit within the primary sear depression when the safety sear and the primary sear are coupled to the sear assembly pin.In some embodiments, the primary sear includes a primary sear extension that extends laterally from the primary sear body, and the primary sear opening is defined through the primary sear extension. In these embodiments, a portion of the safety sear torsion spring and a portion of the primary sear torsion spring may be positioned around the primary sear extension.In certain embodiments, a firearm may include the sear assembly described above. The firearm may also have a firing pin including a firing pin lug that extends from the firing pin so that the firing pin lug vertically overlaps the sear catch and the safety sear rear surface when the primary sear and the safety sear are arranged in a raised position. However, in certain aspects, the firing pin lug does not vertically overlap the sear catch when the primary sear is in the
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lowered position. The sear catch may be positioned rearward of the safety sear rear surface so that the firing pin lug is configured to contact the sear catch at a position that is rearward of a position at which the firing pin lug contacts the safety sear rear surface.The firearm may also include a trigger assembly including a trigger and a trigger bar.The trigger bar may be configured to move rearwardly upon the application of force on the trigger to contact the sear lever; and the sear lever may be configured to rotate upon contact with the trigger bar causing rotation of the primary sear and the safety sear to a lowered position. In some embodiments, there is no contact between the trigger bar and the primary sear upon rearward movement of the trigger bar.In some embodiments, a level surface on the primary sear top edge is positioned betweenthe sear catch and the top sloped surface of the primary sear. In some instances, the firing pin lug is positioned on the level surface of the primary sear top edge when the firing pin lug is in contact with the sear catch.Further forms, objects, features, aspects, benefits, advantages, and embodiments of thepresent invention will become apparent from a detailed description and drawings provided herewith.
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BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view of a firearm.FIG. 2 is a right side view of the firearm of FIG. 1 with the frame and the slide removed.FIG. 3 is a left side view of the firearm of FIG. 1 with the frame and the slide removed. 5 FIG. 4 is a perspective view of a firing pin and a sear assembly of the firearm of FIG. 1.FIG. 5 is a right side view of the sear assembly and a trigger assembly of the firearm of FIG. 1.FIG. 6 is a perspective view of a primary sear of the sear assembly of FIG. 4.FIG. 7 is a left side view of the primary sear of FIG. 6. 10 FIG. 8 is a perspective view of a safety sear of the sear assembly of FIG. 4.FIG. 9 is a left side view of the firing pin and the sear assembly of the firearm of FIG. I with the firing pin held by the primary sear.FIG. 10 is a left side view of the firing pin and the sear assembly of the firearm of FIG. with the firing pin held by the safety sear. 15 FIG. 11 is a left side view of the firing pin and the sear assembly of the firearm of FIG. 9after the trigger has been pulled.
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DESCRIPTION OF THE SELECTED EMBODIMENTS For the purpose of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended. Any alterations and further modifications in the described embodiments, and any further applications of the principles of the invention as described herein are contemplated as would normally occur to one skilled in the art to which the invention relates. One embodiment of the invention is shown in great detail, although it will be apparent to those skilled in the relevant art that some features that are not relevant to the present invention may not be shown for the sake of clarity.Directional terms, such as forward, rearward, top, bottom, etc., are used in this description with reference to the specific embodiment shown and used for purposes of clarity. It should be recognized that these terms are not meant to be limiting. For the purposes of this description, the term “forward” refers to the direction moving toward the front end of the barrel, where a bullet exits upon being fired. The term “rearward” refers to a direction moving toward the grip end of the firearm.A side view of a firearm 20 is shown in FIG. 1. Firearm 20 includes a frame 30 that defines a magazine well 35 for receiving a magazine 40. A slide 50 is positioned atop the frame so that the slide 50 may move along the length of the frame 30. A barrel 60 is supported within the slide 50. The firearm 20 also includes a trigger assembly 110 that is housed within the frame 30. In some embodiments, the trigger assembly 110 may include a trigger 113 and a trigger safety 114 that is protected by a trigger guard 116.FIGS. 2 and 3 show a right side view and a left side view, respectively, of the firearm with the frame 30 and the slide 50 hidden to more clearly show the inner components of the firearm 20. As shown in FIG. 2, the trigger assembly 110 includes a trigger bar 120 that extends rearwardly from the trigger 113 and interacts with a sear assembly 130. The sear assembly 1interacts with the firing pin 160 to allow release of the firing pin when the trigger 113 is pulled so that the firing pin may contact a loaded cartridge to fire the firearm 20.A safety disassembly system 175 includes a safety disassembly lever 185 that is also capable of interaction with the sear assembly 130. The safety disassembly system 175 prevents accidental firing of the firearm 20 during disassembly of the firearm 20. In some embodiments,
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the safety disassembly lever 185 may also prevent disassembly of the firearm 20 when a magazine 40 is inserted into the magazine well. The safety disassembly lever 185 may also prevent insertion of a magazine 40 into the magazine well 35 when the safety disassembly system 175 is in a position to allow disassembly of the firearm 20.A trigger housing 200 may be fit within the frame 30 and may provide support for the trigger assembly 110 and may also provide additional support for the frame 30. In addition to supporting the trigger assembly, the trigger housing 200 may also support the safety disassembly system 175. In some embodiments, the trigger housing 200 may define opposed openings through which a portion of the safety disassembly system 175 may be inserted. The trigger housing 200 may also provide support for a slide stop assembly 240. The slide stop assembly 240 may include a slide stop lever and a slide stop pin. The slide stop assembly 240 allows the slide 50 to be held in a rearward position.A recoil spring assembly 260 is positioned below the barrel 60. The recoil spring assembly 260 assists to return the slide 50 to a forward position after the firearm 20 is fired.A magazine catch assembly 310 is found within the frame 30 and adjacent to the magazine well 35 and the magazine 40 when the magazine 40 is loaded into the magazine well. The magazine catch assembly 310 holds the magazine 40 within the magazine well 35, and operation of the magazine catch assembly allows the magazine 40 to be released from the magazine well 35. In some embodiments, the magazine catch assembly 310 is designed to be ambidextrous so it may be operated by a right-handed or a left-handed user from either side of the firearm 20. Further, in some embodiments, the magazine catch assembly 310 may operate to prevent release of the magazine 40 from the magazine well 35 when the trigger 113 is pulled.The firearm 20 also includes a manual safety assembly 340 which is positioned near the rearward end of the firearm 20. The manual safety assembly 340 may be in contact with and secured to a portion of the trigger housing 200. The manual safety assembly 340 may be rotatable with respect to the trigger housing 200, so that when the manual safety assembly 340 is rotated into an engaged orientation, the manual safety assembly 340 prevents rotation of the sear assembly 130. This prevents the firearm 20 from firing because the sear assembly 130 is unable to rotate to release the firing pin 160.A backstrap assembly 360 is attachable to a rearward face of the frame 30. The backstrap assembly 360 provides a grip for a user firing the firearm 20. The backstrap assembly 360 may
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be designed to ergonomically fit within the hand of a user to increase comfort and make the firearm 20 more secure and easier to handle. In some embodiments, the backstrap assembly 3may be designed to be attached and detached from the frame 30 without the need for an additional tool. Additionally, in some embodiments, the backstrap assembly 360 may include a lanyard assembly 390 that allows a lanyard to be attached the firearm 20.An optical sight assembly 410 may be positioned on the top of the slide 50 of firearm 20. The slide 50 may include multiple mounting locations for the optical sight assembly 410 so that different varieties of optical sight assemblies 410 may be attached to the slide 50 as desired without the need for different mounting plates to be installed on the slide 50.The sear assembly 130 and the interaction of the sear assembly 130 with the firing pin 160 is shown in more detail in FIG. 4. Sear assembly 130 includes a sear lever 132, a safety sear 140 and a primary sear 150. An opening is defined through each of these components of the sear assembly 130. Each of these openings is aligned so that a sear assembly pin 131 may extend through the openings to connect the sear lever 132, safety sear 140, and primary sear 150. Each of the sear lever 132, safety sear 140, and the primary sear 150 are independently rotatable about the sear assembly pin 131.A firing pin safety lever 350 is part of the manual safety assembly 340, but is also in communication with the sear assembly 130. The firing pin safety lever 350 is positioned adjacent to the sear lever 132 and also includes an opening to receive the sear assembly pin 1to couple the firing pin safety lever 350 to the sear assembly pin 131 along with the sear lever 132, the safety sear 140, and the primary sear 150. The firing pin safety lever 350 is independently rotatable about the sear assembly pin 131.The sear assembly 130 also includes a safety sear torsion spring 141 and a primary sear torsion spring 151. The safety sear torsion spring 141 operates independently of the primary sear torsion spring 151 to allow for torsion applied to the primary sear 150 to be separate from the torsion applied to the safety sear 140. The firing pin 160 is positioned above the sear assembly 130 and includes a firing pin lug 161 that interacts with the primary sear 150 prior to the firing of firearm 20.The sear assembly 130 is arranged so that the center of mass of the safety sear 140 and the center of mass of the primary sear 150 are positioned at the center of rotation defined by the
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assembly pin 131. This assists to reduce the risk of an accidental fire when the firearm 20 is dropped or knocked by reducing the influence of inertia on the primary sear 150.The interaction between the trigger assembly 110 and the sear assembly 130 is illustrated in FIG. 5. The trigger bar 120 includes a sear contact surface 121 at the rear portion of the trigger bar 120. The sear contact surface 121 of the trigger bar 120 is aligned with a firing pin safety lever flange 353 and a sear lever flange 133. Pulling on the trigger 113 causes the trigger bar 120 to move rearwardly. As the trigger bar 120 moves rearward, the sear contact surface 1of the trigger bar 120 comes into contact with the safety lever flange 353 and the sear lever flange 133. The force applied by the trigger bar 120 as the trigger bar 120 moves rearwardly causes the firing pin safety lever 350 and the sear lever 132 to rotate about the sear assembly pin 131. The rotation of the sear lever 132 causes the safety sear 140 and the primary sear 150 to also rotate so that the rear portion of the safety sear 140 and the rear portion of the primary sear 150 drop with respect to the firing pin 160.A perspective view of the primary sear 150 is illustrated in FIG. 6 and a side view of the primary sear 150 is shown in FIG. 7. The primary sear 150 incudes a primary sear body 152 that includes a contoured top edge 153. A primary sear extension 158 extends from the primary sear body 152 and defines a primary sear opening 159 for receiving the assembly pin 131 to be able to couple the primary sear 150 to the other components of the sear assembly 130. The rear portion of the contoured top edge 153 of the primary sear 150 includes a top sloped surface 1that leads to a level surface 155. The level surface 155 is adjacent to a sear catch 156 that extends from the top edge 153 of the primary sear 150. A depression 157 of the contoured top edge 153 is positioned forward of and adjacent to the sear catch 156.The safety sear 140 is shown in more detail in FIG. 8. Safety sear 140 includes a safety sear body 142 and a top safety sear edge 143 of the safety sear body 142. The top safety sear edge 143 includes a safety sear rear surface 144. A safety sear flange 145 extends laterally from a rear portion of the top safety sear edge 143. The safety sear flange 145 is configured to be able to fit within the depression 157 of the top edge 153 of the primary sear 150 when the safety sear 140 is arranged adjacent to the primary sear 150 in the sear assembly 130. A safety sear opening 149 is defined through the safety sear body 142. The safety sear opening 149 may align with the primary sear opening 159 and receive the sear assembly pin 131 to couple the safety sear 140 to the other components of the sear assembly 130.
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The combination of the safety sear 140 and the primary sear 150 resist accidental firing of the firearm 20 in the event of the firearm 20 being dropped or any other vibration, jostle, or excitation that may cause movement of the firing pin 160. The safety sear 140 and the primary sear 150 each have a raised position, shown in FIG. 9. The safety sear 140 is biased into a raised position by the safety sear torsion spring 141 and the primary sear 150 is biased into a raised position by the primary sear torsion spring 151. When the safety sear 140 is in the raised position, the safety sear rear surface 144 has a vertical overlap with the firing pin lug 161. When the primary sear 150 is in the raised position, the sear catch has a vertical overlap with the firing pin lug 161.As shown in FIG. 9, the firing pin 160 is positioned so that the firing pin lug 1vertically overlaps the sear catch 156 so that the firing pin lug 161 may rest on the top edge 1of the primary sear 150. Typically, the firing pin lug 161 will initially contact the sloped surface 154 of the primary sear 150 and be biased forward along the sloped surface 154 to the level surface 155 of the primary sear 150 until the firing pin lug 161 comes into contact with the sear catch 156. The sear catch 156 contacts the firing pin lug 161 to prevent the firing pin 160 from moving forward any further. The sloped surface 154 of the primary sear 150 that leads to the level surface 155 immediately adjacent to the sear catch 156 allows for the firing pin 160 and the primary sear 150 to always have the same amount of overlap. This helps to maintain similar trigger movement or feel when pulling the trigger 113 for a single firearm 20 or across a range of similar firearms.In the event the firearm 20 is dropped or there is some other kind of inadvertent movement sufficient to cause brief movement of the primary sear 150 to lower the primary sear 150, there is a risk of the firing pin lug 161 losing contact with the primary sear 150 and moving forward along a firing pin axis 162. For example, if the primary sear 150 rotates to a lowered position so that the sear catch 156 moves downward, contact with the firing pin lug 161 may be lost, and the firing pin 160 may be biased in the forward direction along firing pin axis 162. In such an instance, it is preferable that the firing pin 160 not travel forward until the firing pin 1contacts a loaded cartridge so that the bullet is fired.Advantageously, the safety sear 140 of the present disclosure is capable of assisting to reduce the likelihood this sort of inadvertent firing of the firearm 20. When the safety sear 140 is positioned in its raised position, there is a vertical overlap between the firing pin lug 161 and the
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safety sear rear surface 144, so that the firing pin lug 161 contacts the safety sear rear surface as the firing pin 160 moves in the forward direction (see FIG. 10). In some embodiments, the raised height of the safety sear rear surface 144 may be equal to or greater than the raised height of the sear catch 156. In other embodiments, the raised height of the safety sear rear surface 1may be slightly shorter than the raised height of the sear catch 156.Accordingly, in the unlikely event the firearm 20 is dropped or jostled so that the primary sear 150 rotates independently of the safety sear 140 and the sear catch 156 loses contact with the firing pin lug 161 so that the firing pin 160 moves forward, the firing pin lug 161 preferably contacts the safety sear rear surface 144 and is held by the safety sear 140 prior to the firing pin 160 contacting a cartridge loaded into the firearm 20 and firing the firearm 20.In the unlikely event the firearm 20 is dropped or some other action is sufficient to cause both the safety sear 140 and the primary sear 150 to rotate with respect to the firing pin 160 and subsequently cause the sear catch 156 to lose contact with and release the firing pin 160, preferably, in the time that the firing pin 160 moves forward past the sear catch 156, the torsion spring 141 may bias the safety sear 140 back to the raised position so that the safety sear rear surface 144 may impede the movement of the firing pin 160 and prevent the firearm 20 from being fired.The sear assembly 130 also allows for the firearm 20 to be fired upon intentional pulling of the trigger 113. As shown in FIG. 11, when the trigger 113 is intentionally pulled to fire the firearm 20, the force applied to the trigger 113 is transferred to the trigger bar 120, which causes rotation of the sear lever 132, which in turn causes rotation of both the safety sear 140 and the primary sear 150. Such rotation may be accomplished by a lateral protrusion of the sear lever 132 which is positioned beneath forward protruding portions of the safety sear 140 and the primary sear 150 such that rearward movement of the trigger bar rotates the sear lever 132 to raise the lateral protrusion and raise the forward protruding portions of both the safety sear 1and the primary sear 150.When pulling the trigger 113 to fire the firearm, the primary sear 150 is rotated into a lowered position to allow the firing pin lug 161 to be released by the scar catch 156. The safety sear 140 is also rotated into a lowered position upon pulling the trigger 113. When the safety sear 140 is in the lowered position, the safety sear rear surface 144 drops below the position of the firing pin lug 161, so that the firing pin lug 161 may move past the safety sear 140 without
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contacting the safety sear rear surface 144 while pressure is maintained on the trigger 113. Therefore, pulling the trigger 113 to intentionally fire the firearm 20 disengages the safety sear 140.The following numbered clauses set out specific embodiments that may be useful in understanding the present invention:1. A sear assembly comprising:a primary sear including a primary sear body having a primary sear top edge, wherein a sear catch extends from said primary sear top edge and a top sloped surface is positioned rearward of said sear top edge, and wherein a primary sear opening is defined through said primary sear body;a safety sear including a safety sear body having a safety sear rear surface, and wherein a safety sear opening is defined through said safety sear body;a sear assembly pin, wherein said sear assembly pin is insertable within said primary sear opening and said safety sear opening when said primary sear opening is aligned with said safety sear opening; andwherein each of said primary sear and said safety sear are independently rotatable about said sear assembly pin.2. The sear assembly of claim 1, further comprising:a sear lever, wherein said sear lever surrounds said sear assembly pin; andwherein rotation of the sear lever about said sear assembly pin causes rotation of said primary sear and said safety sear about said sear assembly pin.3. The sear assembly of any preceding clause, further comprising:a safety sear torsion spring, wherein said safety sear torsion spring applies tension to said safety sear.4. The sear assembly of clause 3, further comprising:a primary sear torsion spring, wherein said primary sear torsion spring applies tension to said primary sear.5. The sear assembly of clause 4, wherein tension applied to said safety sear by said safety sear torsion spring is independent of the tension applied to said primary sear by said primary sear torsion spring.6. The sear assembly of any preceding clause,
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wherein said safety sear includes a safety sear flange that extends laterally from said safety sear body;wherein said primary sear includes a primary sear depression defined in said primary sear top edge;wherein said safety sear flange fits within said primary sear depression when said safety sear and said primary sear are coupled to said sear assembly pin.7. The sear assembly of any preceding clause, wherein a level surface on said primary sear top edge is positioned between said sear catch and said top sloped surface of said primary sear.8. The sear assembly of any preceding clause, wherein said primary sear includes a primary sear extension that extends laterally from said primary sear body, and wherein said primary sear opening is defined through said primary sear extension.9. The sear assembly of clause 8, further comprising:a safety sear torsion spring, wherein said safety sear torsion spring applies tension to said safety sear;a primary sear torsion spring, wherein said primary sear torsion spring applies tension to said primary sear; andwherein a portion of said safety sear torsion spring and a portion of said primary sear torsion spring are positioned around said primary sear extension.10. A firearm comprising:a primary sear including a primary sear body having a primary sear top edge, wherein a sear catch extends from said primary sear top edge, and wherein a primary sear opening is defined through said primary sear body;a safety sear including a safety sear body having a safety sear rear surface, and wherein a safety sear opening is defined through said safety sear body;a sear assembly pin, wherein said sear assembly pin is insertable within said primary sear opening and said safety sear opening when said primary sear opening is aligned with said safety sear opening, and wherein said sear assembly pin defines a center of rotation for said primary sear and said safety sear;a firing pin including a firing pin lug that extends from said firing pin so that said firing pin lug vertically overlaps said sear catch and said safety sear rear surface when said primary sear and said safety sear are arranged in a raised position; and
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wherein said sear catch is positioned rearward of said safety sear rear surface so that said firing pin lug is configured to contact said sear catch at a position that is rearward of a position at which said firing pin lug contacts said safety sear rear surface.11. The firearm of clause 10, further comprising:a sear lever, wherein said sear lever surrounds said sear assembly pin; andwherein rotation of the sear lever about said sear assembly pin causes rotation of said primary sear and said safety sear about said sear assembly pin.12. The firearm of any one of clauses 10-11, further comprising:a trigger assembly including a trigger and a trigger bar;wherein said trigger bar is configured to move rearwardly upon the application of force on said trigger to contact said sear lever; andwherein said sear lever is configured to rotate upon contact with said trigger bar causing rotation of said primary sear and said safety sear to a lowered position.13. The firearm of clause 12, wherein said firing pin lug does not vertically overlap said sear catch when said primary sear is in said lowered position.14. The firearm of clause 12, wherein said firing pin lug does not vertically overlap said safety sear rear surface when said safety sear is in said lowered position.15. The firearm of clause 12, wherein there is no contact between said trigger bar and said primary sear upon rearward movement of said trigger bar.16. The firearm of clause 15, wherein there is no contact between said trigger bar and said safety sear upon rearward movement of said trigger bar.17. The sear assembly of any one of clauses 10-16,wherein said primary sear top edge includes a top sloped surface positioned rearward of said sear catch;wherein said primary sear top edge includes a level surface between said sear catch and said top sloped surface; andwherein firing pin lug is in contact with said top sloped surface as the firing pin moves forward toward said sear catch.18. The firearm of clause 17,wherein said firing pin lug is positioned on said level surface of said primary sear top edge when said firing pin lug is in contact with said sear catch.
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19. The firearm of any one of clauses 10-18, wherein said primary sear and said safety sear each have a center of mass that is located at said center of rotation defined by said sear assembly pin.20. The firearm of any one of clauses 10-19, further comprising: 5 a primary sear torsion spring, wherein said primary sear torsion spring applies tension tosaid primary sear;a safety sear torsion spring, wherein said safety sear torsion spring applies tension to said safety sear; andwherein the tension applied to said primary sear by said primary sear torsion spring isindependent of the tension applied to said safety sear by said safety sear torsion spring.While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only the preferred embodiment has been shown and described and that all changes, equivalents, and modifications that come within the spirit of the inventions defined 15by following claims are desired to be protected. All publications, patents, and patent applications cited in this specification are herein incorporated by reference as if each individual publication, patent, or patent application were specifically and individually indicated to be incorporated by reference and set forth in its entirety herein.
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