# US 11,110,576 B2 · Gas spring fastener driver > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,110,576 B2 - Document ID: US11110576B2 - Status: Granted - Kind: B2 - Application number: 16/773,086 - Filed: 2020-01-27 - Published: 2020-05-21 - Granted: 2021-09-07 - Earliest claimed: 2016-06-21 - Assignees: Techtronic Cordless GP - Applicants: Techtronic Cordless Gp - Inventors: Essam Namouz - Web page: https://patentgrep.com/patent/US11110576B2 ## CPC - B25C 1/046: {Trigger valve and trigger mechanism} - B25C 1/045: {main valve and main cylinder} - B25C 1/047: {Mechanical details} - B25C 1/06: operated by electric power - B25C 1/04: operated by fluid pressure {, e.g. by air pressure} - B25C: HAND-HELD NAILING OR STAPLING TOOLS; MANUALLY OPERATED PORTABLE STAPLING TOOLS (for shoemaking A43D) ## Abstract A fastener driver includes a drive blade movable from a retracted position to a driven position for driving a fastener into a work piece. The fastener driver further includes a gas spring mechanism for driving the drive blade from the retracted position to the driven position. The gas spring mechanism is moveable between a retracted state and a driven state. The fastener driver further includes a first return mechanism for moving the drive blade from the driven position toward the retracted position, and a second return mechanism for returning the gas spring mechanism toward the retracted state separately from movement of the drive blade. ## Claims ### Claim 1 A fastener driver comprising: a drive blade movable from a retracted position to a driven position for driving a fastener into a workpiece; a gas spring mechanism for driving the drive blade from the retracted position to the driven position, the gas spring mechanism being movable between a retracted state and a driven state; a first return mechanism for moving the drive blade from the driven position toward the retracted position; and a second return mechanism for returning the gas spring mechanism toward the retracted state separately from movement of the drive blade. ### Claim 2 (depends on 1) The fastener driver of claim 1, wherein the second return mechanism returns the gas spring toward the retracted state as the drive blade returns toward the retracted position. ### Claim 3 (depends on 1) The fastener driver of claim 1, wherein the second return mechanism returns the gas spring toward the retracted state as the drive blade is still advancing toward the driven position. ### Claim 4 (depends on 1) The fastener driver of claim 1, wherein a firing operation of the fastener driver is complete when the drive blade reaches the driven position, and wherein the second return mechanism is configured to return the gas spring mechanism toward the retracted state immediately after a firing operation is completed. ### Claim 5 (depends on 1) The fastener driver of claim 1, wherein the gas spring mechanism includes a piston movable between a retracted position and a driven position, wherein in the driven state of the gas spring mechanism, the piston is in the driven position, and in the retracted state of the gas spring mechanism, the piston is in the retracted position. ### Claim 6 (depends on 5) The fastener driver of claim 5, wherein when the gas spring mechanism is in the retracted state and the drive blade is in the retracted position, the piston abuts the drive blade. ### Claim 7 (depends on 5) The fastener driver of claim 5, wherein when the gas spring mechanism is in the driven state and the drive blade is in the driven position, the piston is spaced from the drive blade. ### Claim 8 (depends on 1) The fastener driver of claim 1, wherein the first return mechanism is an extensible cylinder. ### Claim 9 (depends on 8) The fastener driver of claim 8, further comprising a main housing in which the gas spring mechanism, the first return mechanism, and the second return mechanism are at least partly enclosed, wherein the extensible cylinder comprises a cylinder housing coupled to one of the main housing or the drive blade, and a rod coupled to the other of the main housing or the drive blade. ### Claim 10 (depends on 1) The fastener driver of claim 1, wherein the second return mechanism comprises a cam lobe engageable with the gas spring mechanism, and wherein the gas spring mechanism is moved from the driven state to the retracted state in response to rotation of the cam lobe. ### Claim 11 (depends on 10) The fastener driver of claim 10, wherein the gas spring mechanism includes a piston movable between a driven position and a retracted position, and wherein a follower is coupled for movement with the piston. ### Claim 12 (depends on 11) The fastener driver of claim 11, wherein the follower comprises a pin engageable with the cam lobe. ### Claim 13 (depends on 1) The fastener driver of claim 1, wherein the second return mechanism includes a cam lobe rotatably supported on a cam shaft, and wherein the drive blade includes a groove that receives the cam shaft to prevent engagement between the drive blade and the cam shaft as the drive blade moves between the retracted position and the driven position. ### Claim 14 A method of operating a fastener driver, the method comprising: initiating a drive cycle; releasing a gas spring mechanism from a retracted state thereby driving a drive blade from a retracted position to a driven position; moving the drive blade from the driven position toward the retracted position with a first return mechanism; and moving the gas spring mechanism from a driven state toward the retracted state with a second return mechanism, the second return mechanism configured to return the gas spring mechanism toward the retracted state separately from the drive blade. ### Claim 15 (depends on 14) The method of claim 14, further comprising moving the gas spring mechanism from the driven state toward the retracted state immediately after a firing operation of the fastener driver is complete, wherein a firing operation is complete when the drive blade reaches the driven position. ### Claim 16 (depends on 14) The method of claim 14, wherein the first return mechanism is an extensible cylinder including a cylinder housing coupled to one of a main housing or the drive blade and a rod coupled to the other of the main housing or the drive blade, and wherein the method further comprises: creating a vacuum in the cylinder housing for biasing the rod toward a retracted position. ### Claim 17 (depends on 14) The method of claim 14, wherein the second return mechanism includes a cam lobe engageable with the second return mechanism, and wherein the method further comprises: rotating the cam lobe to move the gas spring mechanism from the driven state to the retracted state; and rotating the cam lobe to release the gas spring mechanism. ### Claim 18 (depends on 14) The method of claim 14, wherein the step of moving the gas spring mechanism from the driven state toward the retracted state with a second return mechanism is performed as the drive blade returns toward the retracted position. ### Claim 19 (depends on 14) The method of claim 14, wherein the step of moving the gas spring mechanism from the driven state toward the retracted state with a second return mechanism is performed as the drive blade is still advancing toward the driven position. ### Claim 20 (depends on 14) The method of claim 14, wherein the second return mechanism includes a cam lobe rotatably supported on a cam shaft, and wherein the drive blade includes a groove that receives the cam shaft to prevent engagement between the drive blade and the cam shaft as the drive blade moves between the retracted position and the driven position.