# US 11,440,632 B2 · Boat lift > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,440,632 B2 - Document ID: US11440632B2 - Status: Granted - Kind: B2 - Application number: 16/895,829 - Filed: 2020-06-08 - Published: 2020-09-24 - Granted: 2022-09-13 - Earliest claimed: 2017-05-26 - Assignees: Lippert Components, Inc. - Applicants: Lippert Components, Inc. - Inventors: Robert L. Tiedge; Mark Kinder; Nicholas Cornett - Web page: https://patentgrep.com/patent/US11440632B2 ## CPC - B63C 1/02: Floating docks ({externally attached cofferdams and the like B63B17/0018; } ship transporters with adjustable draught B63B35/42) - B63C 3/06: by vertical movement of vessel, i.e. by crane - B63C 3/12: using cradles (vehicles in general for transporting boats or the like B60P) - B63C 5/02: Stagings; Scaffolding; Shores or struts - B63C: LAUNCHING, HAULING-OUT, OR DRY-DOCKING OF VESSELS; LIFE-SAVING IN WATER; EQUIPMENT FOR DWELLING OR WORKING UNDER WATER; MEANS FOR SALVAGING OR SEARCHING FOR UNDERWATER OBJECTS (floating nets, floating slipways, or the like for recovering aircraft from the water B63B35/52) ## Abstract A boat lift includes posts and linear actuators, each attached to one of the posts. Each linear actuator includes an extendable and retractable member oriented for extension and retraction substantially parallel to the post. Ends of a first pair of the extendable and retractable members are connected to a first carrier, and ends of a second pair of the extendable and retractable members are connected to a second carrier. A cradle or platform is supported by the first and second carriers. The boat lift may be supported by the ground, by a structure, for example, a dock, a sea wall or a wall of a boat house, or by pontoons. ## Claims ### Claim 1 A boat lift comprising: a structure; a pair of forward actuators coupled with the structure; a pair of aft actuators coupled with the structure; a forward carrier connected between the pair of forward actuators; and an aft carrier connected between the pair of aft actuators, wherein the forward and aft actuators are configured relative to the structure so as to be positioned above a water line, and wherein the forward and aft actuators are displaceable between a retracted position in which the forward and aft carriers are raised relative to the water line and an extended position in which the forward and aft carriers are lowered relative to the water line, wherein the forward and aft actuators are hydraulically coupled through corresponding hydraulic conduits to a hydraulic circuit including a hydraulic pump and a hydraulic fluid reservoir. ### Claim 2 (depends on 1) A boat lift according to claim 1, further comprising a hull support connected between the forward carrier and the aft carrier. ### Claim 3 (depends on 2) A boat lift according to claim 2, comprising multiple hull supports connected between the forward carrier and the aft carrier. ### Claim 4 (depends on 2) A boat lift according to claim 2, wherein the hull support comprises a platform hull support. ### Claim 5 (depends on 1) A boat lift according to claim 1, wherein at least one of the forward carrier and the aft carrier is telescopically extendable and retractable. ### Claim 6 (depends on 1) A boat lift according to claim 1, wherein the hydraulic pump is bi-directional. ### Claim 7 (depends on 6) A boat lift according to claim 6, wherein the hydraulic circuit comprises a plurality of flow divider valves that are configured to equalize respective rates of extension and retraction of the forward and aft actuators. ### Claim 8 A boat lift comprising: a structure; a pair of forward actuators coupled with the structure; a pair of aft actuators coupled with the structure; a forward carrier connected between the pair of forward actuators; and an aft carrier connected between the pair of aft actuators, wherein the forward and aft actuators are configured relative to the structure so as to be positioned above a water line, and wherein the forward and aft actuators are displaceable between a retracted position in which the forward and aft carriers are raised relative to the water line and an extended position in which the forward and aft carriers are lowered relative to the water line, wherein the structure comprises a space frame configured for placement on a surface below the water line, the space frame comprising four support posts arranged to define a quadrilateral and frame members connected between the support posts. ### Claim 9 (depends on 8) A boat lift according to claim 8, wherein the support posts are telescopically adjustable. ### Claim 10 (depends on 8) A boat lift according to claim 8, wherein the space frame comprises an additional frame member connected between the frame members that are connected between the support posts, the additional frame member defining a support structure for a platform or deck. ### Claim 11 (depends on 8) A boat lift according to claim 8, further comprising canopy supports connected between the frame members. ### Claim 12 (depends on 8) A boat lift according to claim 8, wherein the forward actuators and the aft actuators are connected to respective ones of the support posts of the space frame. ### Claim 13 (depends on 12) A boat lift according to claim 12, wherein a vertical position of the forward and aft actuators with respect to the support posts is adjustable. ### Claim 14 (depends on 8) A boat lift according to claim 8, wherein a floating dock is associated with the space frame, the floating dock including at least one pontoon or float unit and a deck or platform disposed thereon, the boat lift comprising a sleeve connected to the pontoon and the floating dock adjacent corresponding locations of the support posts, wherein the sleeves receive a corresponding one of the support posts in sliding engagement. ### Claim 15 A boat lift comprising: a structure including a space frame configured for placement on a surface below the water line, the space frame comprising four support posts arranged to define a quadrilateral and frame members connected between the support posts; four linear actuators respectively connected to each of the support posts, the four linear actuators including a forward pair of linear actuators and an aft pair of linear actuators, each of the linear actuators including a cylinder and a piston rod displaceable in the cylinder; a forward carrier connected between the piston rods of the forward pair of linear actuators; and an aft carrier connected between the piston rods of the aft pair of linear actuators, wherein the forward pair of linear actuators are configured to selectively move the forward carrier between a first position relatively near upper ends of the support posts by retracting their respective piston rods and a second position relatively near lower ends of the support posts by extending their respective piston rods, and wherein the aft pair of linear actuators are configured to selectively move the aft carrier between a first position relatively near the upper ends of the support posts by retracting their respective piston rods and a second position relatively near the lower ends of the support posts by extending their respective piston rods.