# US 7,607,724 B2 · Collapsible support structure > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,607,724 B2 - Document ID: US7607724B2 - Status: Granted - Kind: B2 - Application number: 11/838,523 - Filed: 2007-08-14 - Published: 2008-02-21 - Granted: 2009-10-27 - Earliest claimed: 2006-08-16 - Assignees: Promen-Aid Innovations Ltd. - Inventors: Robert G. Dickie; Steve A. Copeland - Web page: https://patentgrep.com/patent/US7607724B2 ## CPC - B62B 7/06: collapsible or foldable - A61G 5/0816: {folding side to side, e.g. reducing or expanding the overall width of the wheelchair} - A61G 5/085: {folding up and down, e.g. reducing or expanding the overall height of the wheelchair} - A61G 5/0891: {having rigid supports, e.g. seat or back supports which retain their shape after folding of the wheelchair} - B62B 7/068: {by sliding a bushing along a rod, e.g. like folding means of an umbrella} - B62B 2205/003: with actuation mechanisms which drive the folding or unfolding operation - B62B: HAND-PROPELLED VEHICLES, e.g. HAND CARTS OR PERAMBULATORS; SLEDGES (characterised by animal propulsion B62C; propulsion of sledges by driver or engine B62M) - A61G: TRANSPORT, PERSONAL CONVEYANCES OR ACCOMMODATION SPECIALLY ADAPTED FOR PATIENTS OR DISABLED PERSONS (appliances for aiding patients or disabled persons to walk A61H3/00); OPERATING TABLES OR CHAIRS; CHAIRS FOR DENTISTRY; FUNERAL DEVICES (embalming corpses A01N1/00) ## Abstract An apparatus including a support structure movable between an erected position and a collapsed position and including a threaded shaft, a first collapsible assembly having a first portion pivotally mounted on the threaded shaft, a second collapsible assembly having a second portion pivotally mounted on the threaded shaft, where at least one of the first and second portions is threadably engaged to the threaded shaft such that the first and second portions are relatively movable toward and away from each other through a rotation of the threaded shaft to move the support structure between the erected and collapsed positions. ## Claims ### Claim 1 An apparatus comprising a support structure movable between an erected position and a collapsed position and comprising a threaded shaft, a first collapsible assembly having a first portion pivotally mounted on the threaded shaft through a first hub, a second collapsible assembly having a second portion pivotally mounted on the threaded shaft through a second hub, at least one of the first and second hubs being threadably engaged to the threaded shaft such that the first and second hubs are relatively movable toward and away from each other through a rotation of the threaded shaft to move the support structure between the erected and collapsed positions, the first collapsible assembly including first and second struts pivotally mounted on the first hub, the second collapsible assembly including third and fourth struts pivotally mounted on the second hub, the apparatus further comprising a first seat pole pivotally connected to the first and third struts, a second seat role pivotally connected to the second and fourth struts, and a seat connected to the first and second seat poles and adapted for the seating of a person thereon. ### Claim 2 (depends on 1) The apparatus of claim 1, further comprising a crank rotationally connected to the threaded shaft such as to rotate integrally therewith, the crank being at least partially slidably received within a hollow portion of the threaded shaft. ### Claim 3 (depends on 1) The apparatus of claim 1, further comprising a motor assembly rotating the threaded shaft. ### Claim 4 (depends on 3) The apparatus of claim 3, further comprising limit sensors for stopping the motor when the support structure reaches the erected and collapsed positions. ### Claim 5 (depends on 1) The apparatus of claim 1 further comprising a flexible tension strap extending between first and second locations disposed on the support structure, and wherein the strap is under tension in the erected position to bias the first and second locations toward one another. ### Claim 6 (depends on 1) The apparatus of claim 1 further comprising a first arm pole pivotally connected to the first seat pole, a first back pole pivotally connected to the first seat pole and to the first arm pole, a second arm pole pivotally connected to the second seat pole, a second back pole pivotally connected to the second seat pole and to the second arm pole, and a back member connected to the first and second back poles and adapted for the person's back to lean against. ### Claim 7 (depends on 1) The apparatus of claim 1 wherein the first collapsible assembly comprises a third portion and the second collapsible assembly comprises a fourth portion, and wherein during movement of the support structure from the erected position to the collapsed position the first and second portions relatively move toward one another and the third and fourth portions relatively move away from each other, and further comprising a leg assembly adapted for contacting a support surface and having first and second legs, the first leg being pivotally connected to the third portion, and the second leg being pivotally connected to the fourth portion. ### Claim 8 (depends on 1) The apparatus of claim 1 wherein the first collapsible assembly comprises a third portion and the second collapsible assembly comprises a fourth portion, and wherein during movement of the support structure from the erected position to the collapsed position the first and second portions relatively move toward one another and the third and fourth portions relatively move away from each other, the first and second seat poles respectively corresponding to first and second telescoping poles each having first and second segments slidably connected to one another, the first segments of the first and second telescoping poles being pivotally connected to the third portion and the second segments of the first and second telescoping poles being pivotally connected to the fourth portion. ### Claim 9 (depends on 1) The apparatus of claim 1 further comprising a central structure disposed intermediate the first and second hubs, and a leg assembly adapted for contacting a support surface and comprising first, second, third and fourth legs which are pivotally connected to and extend radially outwardly from the central structure. ### Claim 10 (depends on 9) The apparatus of claim 9 further comprising a fifth strut pivotally connected to the first hub and the first leg, a sixth strut pivotally connected to the first hub and the second leg, a seventh strut pivotally connected to the second hub and the third leg, and an eighth strut pivotally connected to the second hub and the fourth leg. ### Claim 11 (depends on 10) The apparatus of claim 10 wherein the seat poles, the threaded shaft, the legs and the struts are parallel to one another in the collapsed position. ### Claim 12 An apparatus comprising a support structure movable between an erected position and a collapsed position and comprising a threaded shall, a first collapsible assembly having a first portion pivotally mounted on the threaded shaft through a first hub, a second collapsible assembly having a second portion pivotally mounted on the threaded shaft through a second hub, at least one of the first and second hubs being threadably engaged to the threaded shall such that the first and second hubs are relatively movable toward and away from each other through a rotation of the threaded shaft to move the support structure between the erected and collapsed positions, the first collapsible assembly including a first strut pivotally mounted on the first hub, the second collapsible assembly including a second strut pivotally mounted on the second hub, the apparatus further comprising a leg assembly adapted for contacting a support surface and comprising first and second legs pivotally mounted on the threaded shaft, wherein the first leg is pivotally connected to the first strut and the second leg is pivotally connected to the second strut. ### Claim 13 (depends on 12) The apparatus of claim 12 further comprising first and second seat poles, the first collapsible assembly including third and fourth struts pivotally connected to the first hub wherein one of the third and fourth struts is pivotally connected to the first seat pole and another of the third and fourth struts is pivotally connected to the second seat pole, the second collapsible assembly including fifth and sixth struts pivotally connected to the second hub wherein one of the fifth and sixth struts is pivotally connected to the first seat pole and another of the fifth and sixth struts is pivotally connected to the second seat pole, and a seat connected to the first and second seat poles and adapted for the seating of a person thereon. ### Claim 14 (depends on 12) The apparatus of claim 12 further comprising third and fourth legs pivotally mounted on the threaded shaft, a third strut pivotally connected to the first hub and the third leg, a fourth strut pivotally connected to the second hub and the fourth leg, first and second seat poles, a fifth strut pivotally connected to the first hub and the first seat pole, a sixth strut pivotally connected to the first hub and the second seat pole, a seventh strut pivotally connected to the second hub and the first seat pole, and an eighth strut pivotally connected to the second hub and the second seat pole, the first and second seat poles being adapted to support a seat for the seating of a person thereon. ### Claim 15 (depends on 14) The apparatus of claim 14 further comprising a first arm pole, a first back pole pivotally connected to the first arm pole, a second arm pole, a second back pole pivotally connected to the second arm pole, wherein the first arm pole and the first back pole are pivotally connected to the first seat pole, and the second arm pole and the second back pole are pivotally connected to the second seat pole, the first and second back poles being adapted to support a back member for the person's back to lean against. ### Claim 16 (depends on 14) The apparatus of claim 14 wherein the seat poles, the threaded shaft, the legs and the struts are parallel to one another in the collapsed position. ### Claim 17 (depends on 12) The apparatus of claim 12, further comprising a crank rotationally connected to the threaded shaft such as to rotate integrally therewith, the crank being at least partially slidably received within a hollow portion of the threaded shaft. ### Claim 18 (depends on 12) The apparatus of claim 12, further comprising a motor assembly rotating the threaded shaft. ### Claim 19 A collapsible chair being alternately configurable in an erected position and a collapsed position, the chair comprising a rotatable threaded shaft, first and second hubs threadably engaged to the threaded shaft to be relatively movable therealong in opposite directions during movement between the erected and collapsed positions through rotation of the threaded shaft, a first collapsible assembly pivotally mounted on the first hub, a second collapsible assembly pivotally mounted on the second hub, a first seat pole interconnecting the first and second collapsible assemblies, a second seat pole interconnecting the first and second collapsible assemblies, a length of the first and second seat poles varying during the movement between the erected and collapsed positions, and a seat member retained on the first and second seat poles. ### Claim 20 (depends on 19) The chair of claim 19, further comprising a central member located at a fixed position along the threaded shaft, each of the first and second collapsible assemblies being pivotally connected to the central member. ### Claim 21 (depends on 19) The chair of claim 19, further comprising a first back pole pivotally connected to the first seat pole at a first location, a first arm pole pivotally connected to the first back pole and to the first seat pole at a second location, a second back pole pivotally connected to the second seat pole at a third location, a second arm pole pivotally connected to the second back pole and to the second seat pole at a fourth location, and a back member retained by the first and second back poles, the variation in the length of the first and second seat poles causing a variation in a distance between the first and second locations and in a distance between the third and fourth locations.